Updated on 2022/05/21

写真a

 
YASUDA, Kenji
 
Affiliation
Faculty of Science and Engineering, School of Advanced Science and Engineering
Job title
Professor

Concurrent Post

  • Faculty of Science and Engineering   Graduate School of Advanced Science and Engineering

Research Institute

  • 2020
    -
    2022

    理工学術院総合研究所   兼任研究員

Education

  • 　
    -
    1992

    Waseda Univ.  

  • 　
    -
    1990

    Waseda Univ.   Depeartment of Physics  

Degree

  • Ph.D.

Research Experience

  • 2016.04
    -
    　

    Waseda University   Professor

  • 2006.04
    -
    2016.03

    Tokyo Medical and Dental Univ.   Professor

  • 2006.04
    -
    2006.09

    The University of Tokyo   Professor

  • 1999.04
    -
    2006.03

    The University of Tokyo   Associate Prof.

  • 1992.04
    -
    1999.03

    Hitachi Ltd.   Advanced Research Lab.   Research Scientist

Professional Memberships

  • 　
    　
    　

    Acoustical Society of America

  • 　
    　
    　

    Biophysical Society

  • 　
    　
    　

    The Japan Society of Applied Physics

  • 　
    　
    　

    The Physical Society of Japan

  • 　
    　
    　

    The Biophysical Society of Japan

 

Research Areas

  • Biophysics

  • Biophysics, chemical physics and soft matter physics

  • Nanobioscience

Papers

  • Photothermal Agarose Microfabrication Technology for Collective Cell Migration Analysis

    Mitsuru Sentoku, Hiromichi Hashimoto, Kento Iida, Masaharu Endo, Kenji Yasuda

    Micromachines   12 ( 9 )  2021.08

    　View Summary

    Agarose photothermal microfabrication technology is one of the micropatterning techniques that has the advantage of simple and flexible real-time fabrication even during the cultivation of cells. To examine the ability and limitation of the agarose microstructures, we investigated the collective epithelial cell migration behavior in two-dimensional agarose confined structures. Agarose microchannels from 10 to 211 micrometer width were fabricated with a spot heating of a focused 1480 nm wavelength infrared laser to the thin agarose layer coated on the cultivation dish after the cells occupied the reservoir. The collective cell migration velocity maintained constant regardless of their extension distance, whereas the width dependency of those velocities was maximized around 30 micrometer width and decreased both in the narrower and wider microchannels. The single-cell tracking revealed that the decrease of velocity in the narrower width was caused by the apparent increase of aspect ratio of cell shape (up to 8.9). In contrast, the decrease in the wider channels was mainly caused by the increase of the random walk-like behavior of component cells. The results confirmed the advantages of this method: (1) flexible fabrication without any pre-designing, (2) modification even during cultivation, and (3) the cells were confined in the agarose geometry.

    DOI

  • Stepwise neuronal network pattern formation in agarose gel during cultivation using non-destructive microneedle photothermal microfabrication

    Yuhei Tanaka, Haruki Watanabe, Kenji Shimoda, Kazufumi Sakamoto, Yoshitsune Hondo, Mitsuru Sentoku, Rikuto Sekine, Takahito Kikuchi, Kenji Yasuda

    Scientific Reports   11 ( 1 )  2021.07

    Authorship：Last author, Corresponding author

    　View Summary

    <title>Abstract</title>Conventional neuronal network pattern formation techniques cannot control the arrangement of axons and dendrites because network structures must be fixed before neurite differentiation. To overcome this limitation, we developed a non-destructive stepwise microfabrication technique that can be used to alter microchannels within agarose to guide neurites during elongation. Micropatterns were formed in thin agarose layer coating of a cultivation dish using the tip of a 0.7 <inline-formula><alternatives><tex-math>$$\upmu \mathrm{m}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
    <mml:mrow>
    <mml:mi>μ</mml:mi>
    <mml:mi>m</mml:mi>
    </mml:mrow>
    </mml:math></alternatives></inline-formula>-diameter platinum-coated glass microneedle heated by a focused 1064-nm wavelength infrared laser, which has no absorbance of water. As the size of the heat source was 0.7 <inline-formula><alternatives><tex-math>$$\upmu \mathrm{m}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
    <mml:mrow>
    <mml:mi>μ</mml:mi>
    <mml:mi>m</mml:mi>
    </mml:mrow>
    </mml:math></alternatives></inline-formula>, which is smaller than the laser wavelength, the temperature fell to 45 <inline-formula><alternatives><tex-math>$$^\circ \hbox {C}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
    <mml:mrow>
    <mml:msup>
    <mml:mrow />
    <mml:mo>∘</mml:mo>
    </mml:msup>
    <mml:mtext>C</mml:mtext>
    </mml:mrow>
    </mml:math></alternatives></inline-formula> within a distance of 7.0 <inline-formula><alternatives><tex-math>$$\upmu \mathrm{m}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
    <mml:mrow>
    <mml:mi>μ</mml:mi>
    <mml:mi>m</mml:mi>
    </mml:mrow>
    </mml:math></alternatives></inline-formula> from the edge of the etched agarose microchannel. We exploited the fast temperature decay property to guide cell-to-cell connection during neuronal network cultivation. The first neurite of a hippocampal cell from a microchamber was guided to a microchannel leading to the target neuron with stepwise etching of the micrometer resolution microchannel in the agarose layer, and the elongated neurites were not damaged by the heat of etching. The results indicate the potential of this new technique for fully direction-controlled on-chip neuronal network studies.

    DOI PubMed

  • Emergent synchronous beating behavior in spontaneous beating cardiomyocyte clusters

    Kazufumi Sakamoto, Yoshitsune Hondo, Naoki Takahashi, Yuhei Tanaka, Rikuto Sekine, Kenji Shimoda, Haruki Watanabe, Kenji Yasuda

    Scientific Reports   11 ( 1 )  2021.06

    　View Summary

    We investigated the dominant rule determining synchronization of beating intervals of cardiomyocytes after the clustering of mouse primary and human embryonic-stem-cell (hES)-derived cardiomyocytes. Cardiomyocyte clusters were formed in concave agarose cultivation chambers and their beating intervals were compared with those of dispersed isolated single cells. Distribution analysis revealed that the clusters’ synchronized interbeat intervals (IBIs) were longer than the majority of those of isolated single cells, which is against the conventional faster firing regulation or “overdrive suppression.” IBI distribution of the isolated individual cardiomyocytes acquired from the beating clusters also confirmed that the clusters’ IBI was longer than those of the majority of constituent cardiomyocytes. In the complementary experiment in which cell clusters were connected together and then separated again, two cardiomyocyte clusters having different IBIs were attached and synchronized to the longer IBIs than those of the two clusters’ original IBIs, and recovered to shorter IBIs after their separation. This is not only against overdrive suppression but also mathematical synchronization models, such as the Kuramoto model, in which synchronized beating becomes intermediate between the two clusters’ IBIs. These results suggest that emergent slower synchronous beating occurred in homogeneous cardiomyocyte clusters as a community effect of spontaneously beating cells.

    DOI PubMed

  • Geometric Understanding of Local Fluctuation Distribution of Conduction Time in Lined-Up Cardiomyocyte Network in Agarose-Microfabrication Multi-Electrode Measurement Assay

    Kazufumi Sakamoto, Shota Aoki, Yuhei Tanaka, Kenji Shimoda, Yoshitsune Hondo, Kenji Yasuda

    Micromachines   11 ( 12 ) 1105 - 1105  2020.12

    　View Summary

    We examined characteristics of the propagation of conduction in width-controlled cardiomyocyte cell networks for understanding the contribution of the geometrical arrangement of cardiomyocytes for their local fluctuation distribution. We tracked a series of extracellular field potentials of linearly lined-up human embryonic stem (ES) cell-derived cardiomyocytes and mouse primary cardiomyocytes with 100 kHz sampling intervals of multi-electrodes signal acquisitions and an agarose microfabrication technology to localize the cardiomyocyte geometries in the lined-up cell networks with 100–300 µm wide agarose microstructures. Conduction time between two neighbor microelectrodes (300 µm) showed Gaussian distribution. However, the distributions maintained their form regardless of its propagation distances up to 1.5 mm, meaning propagation diffusion did not occur. In contrast, when Quinidine was applied, the propagation time distributions were increased as the faster firing regulation simulation predicted. The results indicate the “faster firing regulation” is not sufficient to explain the conservation of the propagation time distribution in cardiomyocyte networks but should be expanded with a kind of community effect of cell networks, such as the lower fluctuation regulation.

    DOI

  • On-Chip Multiple Particle Velocity and Size Measurement Using Single-Shot Two-Wavelength Differential Image Analysis

    Shuya Sawa, Mitsuru Sentoku, Kenji Yasuda

    Micromachines   11 ( 11 ) 1011 - 1011  2020.11

    　View Summary

    Precise and quick measurement of samples’ flow velocities is essential for cell sorting timing control and reconstruction of acquired image-analyzed data. We developed a simple technique for the single-shot measurement of flow velocities of particles simultaneously in a microfluidic pathway. The speed was calculated from the difference in the particles’ elongation in an acquired image that appeared when two wavelengths of light with different irradiation times were applied. We ran microparticles through an imaging flow cytometer and irradiated two wavelengths of light with different irradiation times simultaneously to those particles. The mixture of the two wavelength transmitted lights was divided into two wavelengths, and the images of the same microparticles for each wavelength were acquired in a single shot. We estimated the velocity from the difference of its elongation divided by the difference of irradiation time by comparing these two images. The distribution of polystyrene beads’ velocity was parabolic and highest at the center of the flow channel, consistent with the expected velocity distribution of the laminar flow. Applying the calculated velocity, we also restored the accurate shapes and cross-sectional areas of particles in the images, indicating this simple method for improving of imaging flow cytometry and cell sorter for diagnostic screening of circulating tumor cells.

    DOI

  • Biophysics at Waseda University

    Mitsunori Takano, Kei Yura, Taro Uyeda, Kenji Yasuda

    Biophysical Reviews   12 ( 2 ) 225 - 232  2020.04

    　View Summary

    Biophysics in Waseda University was started in 1965 as one of the three key research areas that constitute the Physics Department. In the biophysics group, one theoretical lab and two experimental labs are now working on the cutting-edge themes on biophysics, disseminating the ideas and knowledge of biophysics to undergraduate and graduate students from the viewpoint of physics.

    DOI

  • Dominant rule of community effect in synchronized beating behavior of cardiomyocyte networks

    Kenji Yasuda

    Biophysical Reviews   12 ( 2 ) 481 - 501  2020.04

    　View Summary

    Exploiting the combination of latest microfabrication technologies and single cell measurement technologies, we can measure the interactions of single cells, and cell networks from “algebraic” and “geometric” perspectives under the full control of their environments and interactions. However, the experimental constructive single cell-based approach still remains the limitations regarding the quality and condition control of those cells. To overcome these limitations, mathematical modeling is one of the most powerful complementary approaches. In this review, we first explain our on-chip experimental methods for constructive approach, and we introduce the results of the “community effect” of beating cardiomyocyte networks as an example of this approach. On-chip analysis revealed that (1) synchronized interbeat intervals (IBIs) of cell networks were followed to the more stable beating cells even their IBIs were slower than the other cells, which is against the conventional faster firing regulation or “overdrive suppression,” and (2) fluctuation of IBIs of cardiomyocyte networks decreased according to the increase of the number of connected cells regardless of their geometry. The mathematical simulation of this synchronous behavior of cardiomyocyte networks also fitted well with the experimental results after incorporating the fluctuation-dissipation theorem into the oscillating stochastic phase model, in which the concept of spatially arranged cardiomyocyte networks was involved. The constructive experiments and mathematical modeling indicated the dominant rule of synchronization behavior of beating cardiomyocyte networks is a kind of stability-oriented synchronization phenomenon as the “community effect” or a fluctuation-dissipation phenomenon. Finally, as a practical application of this approach, the predictive cardiotoxicity is introduced.

    DOI

  • Size Distribution Analysis with On-Chip Multi-Imaging Cell Sorter for Unlabeled Identification of Circulating Tumor Cells in Blood

    Odaka Masao, Kim Hyonchol, Nakamura Yoshiyasu, Hattori Akihiro, Matsuura Kenji, Iwamura Moe, Miyagi Yohei, Yasuda Kenji

    MICROMACHINES   10 ( 2 ) 154 - 154  2019.02  [Refereed]

    　View Summary

    <jats:p>We report a change of the imaging biomarker distribution of circulating tumor cell (CTC) clusters in blood over time using an on-chip multi-imaging flow cytometry system, which can obtain morphometric parameters of cells and those clusters, such as cell number, perimeter, total cross-sectional area, aspect ratio, number of nuclei, and size of nuclei, as “imaging biomarkers”. Both bright-field (BF) and fluorescent (FL) images were acquired at 200 frames per second and analyzed within the intervals for real-time cell sorting. A green fluorescent protein-transfected prostate cancer cell line (MAT-LyLu-GFP) was implanted into Copenhagen rats, and the blood samples of these rats were collected 2 to 11 days later and measured using the system. The results showed that cells having BF area of 90 μm2 or larger increased in number seven days after the cancer cell implantation, which was specifically detected as a shift of the cell size distribution for blood samples of implanted rats, in comparison with that for control blood. All cells with BF area of 150 μm2 or larger were arranged in cell clusters composed of at least two cells, as confirmed by FL nucleus number and area measurements, and they constituted more than 1% of all white blood cells. These results indicate that the mapping of cell size distribution is useful for identifying an increase of irregular cells such as cell clusters in blood, and show that CTC clusters become more abundant in blood over time after malignant tumor formation. The results also reveal that a blood sample of only 50 μL is sufficient to acquire a stable size distribution map of all blood cells to predict the presence of CTC clusters.</jats:p>

    DOI

  • Control of Pressure-Driven Microdroplet Formation and Optimum Encapsulation in Microfluidic System

    Mathias Girault, Akihiro Hattori, Hyonchol Kim, Kenji Matsuura, Masao Odaka, Hideyuki Terazono, Kenji Yasuda

    Oceanography Challenges to Future Earth     181 - 193  2019

    　View Summary

    Formation of stable micro-droplets in multiphase flow is an important step to perform numerous microfluidic applications such as sorting experiments. We herein investigate the conditions of formation of stable micro-droplets using a flow focusing microfluidic device. Two single phases and four different multiphase flow regimes were observed depending on the pressures of fluids. By tuning sample stream pressure against fixed lower oil stream pressure, stable droplet regime can create microenvironment with a diameter ranged from 30 μm to 140 μm. Results obtained show that the formation of strictly size controlled droplets can encapsulate single cell-sized bead into droplet. Moreover, the limit between unstable and stable droplet regimes was the most suitable to efficiently encapsulate cell-sized bead in droplet sorting application. This limit can be precisely monitored by using the change of the droplet speed found at the threshold between these two regimes.

    DOI

  • Electrophysiological evaluation of pentamidine and 17-AAG in human stem cell-derived cardiomyocytes for safety assessment

    Yumiko Asahi, Fumimasa Nomura, Yasuyuki Abe, Masafumi Doi, Tomoko Sakakura, Kiyoshi Takasuna, Kenji Yasuda

    European Journal of Pharmacology   842   221 - 230  2019.01

    　View Summary

    Human ether-a-go-go-related gene (hERG) trafficking inhibition is known to be one of the mechanisms of indirect hERG inhibition, resulting in QT prolongation and lethal arrhythmia. Pentamidine, an antiprotozoal drug, causes QT prolongation/Torsades de Pointes (TdP) via hERG trafficking inhibition, but 17-AAG, a geldanamycin derivative heat shock protein 90 (Hsp90) inhibitor, has not shown torsadogenic potential clinically, despite Hsp90 inhibitors generally being hypothesized to cause TdP by hERG trafficking inhibition. In the present study, we investigated the underlying mechanisms of both drugs’ actions on hERG channels using hERG-overexpressing CHO cells (hERG-CHOs) and human embryonic stem cell-derived cardiomyocytes (hES-CMs). The effects on hERG tail current and protein levels were evaluated using population patch clamp and Western blotting in hERG-CHOs. The effects on field potential duration (FPD) were recorded by a multi-electrode array (MEA) in hES-CMs. Neither drug affected hERG tail current acutely. Chronic treatment with each drug inhibited hERG tail current and decreased the mature form of hERG protein in hERG-CHOs, whereas the immature form of hERG protein was increased by pentamidine but decreased by 17-AAG. In MEA assays using hES-CMs, pentamidine time-dependently prolonged FPD, but 17-AAG shortened it. The FPD prolongation in hES-CMs upon chronic pentamidine exposure is relevant to its clinically reported arrhythmic risk. Cav1.2 or Nav1.5 current were not reduced by chronic application of either drug at a relevant concentration to hERG trafficking inhibition in human embryonic kidney (HEK293) cells. Therefore, the reason why chronic 17-AAG shortened the FPD despite the hERG trafficking inhibition occur is still unknown.

    DOI PubMed

  • On-chip spatiotemporal electrophysiological analysis of human stem cell derived cardiomyocytes enables quantitative assessment of proarrhythmia in drug development

    Yumiko Asahi, Tomoyo Hamada, Akihiro Hattori, Kenji Matsuura, Masao Odaka, Fumimasa Nomura, Tomoyuki Kaneko, Yasuyuki Abe, Kiyoshi Takasuna, Atsushi Sanbuissho, Kenji Yasuda

    Scientific Reports   8 ( 1 ) 14536  2018.09  [Refereed]

    Authorship：Last author, Corresponding author

    　View Summary

    We examined a simultaneous combined spatiotemporal field potential duration (FPD) and cell-to-cell conduction time (CT) in lined-up shaped human embryonic stem cell-derived cardiomyocytes (hESC-CMs) using an on-chip multielectrode array (MEA) system to evaluate two origins of lethal arrhythmia, repolarization and depolarization. The repolarization index, FPD, was prolonged by E-4031 and astemizole, and shortened by verapamil, flecainide and terfenadine at 10 times higher than therapeutic plasma concentrations of each drug, but it did not change after lidocaine treatment up to 100 μM. CT was increased by astemizol, flecainide, terfenadine, and lidocaine at equivalent concentrations of Nav1.5 IC50, suggesting that CT may be an index of cardiac depolarization because the increase in CT (i.e., decrease in cell-to-cell conduction speed) was relevant to Nav1.5 inhibition. Fluctuations (short-term variability; STV) of FPD and CT, STVFPD and STVCT also discriminated between torsadogenic and non-torsadogenic compounds with significant increases in their fluctuation values, enabling precise prediction of arrhythmogenic risk as potential new indices.

    DOI PubMed

  • Selective digestion of Ba2+/Ca2+ alginate gel microdroplets for single-cell handling

    Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    Japanese Journal of Applied Physics   57 ( 6 ) 06HH02-1 - 06HH02-4  2018.06

    　View Summary

    Cells encapsuled by polymer microdroplets are an effective platform for the identification and separation of individual cells for single-cell-based analysis. However, a key challenge is to maintain and release the captured cells in the microdroplets selectively, nondestructively, and noninvasively. We developed a simple method of encapsulating cells in alginate microdroplets having different digestion characteristics. Cells were diluted with an alginate polymer of sol state and encapsulated into microdroplets with Ba2+ and Ca2+ by a spray method. When a chelating buffer was applied, alginate gel microdroplets were digested according to the difference in chelating efficiency of linkage-divalent cations
    hence, two types of alginate microdroplets were formed. Moreover, we examined the capability of the alginate gel to exchange linkage-divalent cations and found that both Ca2+ exchange in Ba-alginate microdroplets and Ba2+ exchange in Ca-alginate microdroplets occurred. These results indicate that the potential applications of a mixture of alginate microdroplets with different divalent cations control the selective digestion of microdroplets to improve the high-throughput, high-content microdroplet-based separation, analysis, or storage of single cells.

    DOI

  • Integrate and fire model with refractory period for synchronization of two cardiomyocytes

    Tatsuya Hayashi, Tetsuji Tokihiro, Hiroki Kurihara, Fumimasa Nomura, Kenji Yasuda

    JOURNAL OF THEORETICAL BIOLOGY   437   141 - 148  2018.01  [Refereed]

    　View Summary

    We investigate an integrate and fire model for two cardiomyocytes interacting with each other. A feature of the model is to incorporate the refractory periods of the cardiomyocytes as well as the influence of firing of adjacent cells. The present model predicts that, if refractory periods of the two cells are nearly equal, the beating rhythms of the two cells always synchronize and their beating rate is tuned to the faster rate between the two cells. On the other hand, if their refractory periods significantly differ, they exhibit various kinds of harmonious beating rhythms. These results successfully explain the well known characteristics of synchronized beating of cultured cardiomyocytes. We also discuss effects of a delay time of cell-to-cell interaction, that gives further complicated phase diagrams for the beating rhythms. (C) 2017 Elsevier Ltd. All rights reserved.

    DOI PubMed

  • Community effect of cardiomyocytes in beating rhythms is determined by stable cells

    Tatsuya Hayashi, Tetsuji Tokihiro, Hiroki Kurihara, Kenji Yasuda

    SCIENTIFIC REPORTS   7 ( 1 ) 15450  2017.11  [Refereed]

    　View Summary

    The community effect of cardiomyocytes was investigated in silico by the change in number and features of cells, as well as configurations of networks. The theoretical model was based on experimental data and accurately reproduced recently published experimental results regarding coupled cultured cardiomyocytes. We showed that the synchronised beating of two coupled cells was tuned not to the cell with a faster beating rate, but to the cell with a more stable rhythm. In a network of cardiomyocytes, a cell with low fluctuation, but not a hight frequency, became a pacemaker and stabilised the beating rhythm. Fluctuation in beating rapidly decreased with an increase in the number of cells (N), almost irrespective of the configuration of the network, and a cell comes to have natural and stable beating rhythms, even for N of approximately 10. The universality of this community effect lies in the fluctuation-dissipation theorem in statistical mechanics.

    DOI PubMed

  • An on-chip imaging droplet-sorting system: a real-time shape recognition method to screen target cells in droplets with single cell resolution

    Mathias Girault, Hyonchol Kim, Hisayuki Arakawa, Kenji Matsuura, Masao Odaka, Akihiro Hattori, Hideyuki Terazono, Kenji Yasuda

    SCIENTIFIC REPORTS   7 ( 1 ) 40072  2017.01  [Refereed]

    　View Summary

    A microfluidic on-chip imaging cell sorter has several advantages over conventional cell sorting methods, especially to identify cells with complex morphologies such as clusters. One of the remaining problems is how to efficiently discriminate targets at the species level without labelling. Hence, we developed a label-free microfluidic droplet-sorting system based on image recognition of cells in droplets. To test the applicability of this method, a mixture of two plankton species with different morphologies (Dunaliella tertiolecta and Phaeodactylum tricornutum) were successfully identified and discriminated at a rate of 10 Hz. We also examined the ability to detect the number of objects encapsulated in a droplet. Single cell droplets sorted into collection channels showed 91 +/- 4.5% and 90 +/- 3.8% accuracy for D. tertiolecta and P. tricornutum, respectively. Because we used image recognition to confirm single cell droplets, we achieved highly accurate single cell sorting. The results indicate that the integrated method of droplet imaging cell sorting can provide a complementary sorting approach capable of isolating single target cells from a mixture of cells with high accuracy without any staining.

    DOI PubMed

  • Algorithm for the Precise Detection of Single and Cluster Cells in Microfluidic Applications

    Mathias Girault, Akihiro Hattori, Hyonchol Kim, Kenji Matsuura, Masao Odaka, Hideyuki Terazono, Kenji Yasuda

    CYTOMETRY PART A   89A ( 8 ) 731 - 741  2016.08  [Refereed]

    　View Summary

    Recent advances in imaging flow cytometry and microfluidic applications have led to the development of suitable mathematical algorithms capable of detecting and identifying targeted cells in images. In contrast to currently existing algorithms, we herein proposed the identification and reconstruction of cell edges based on original approaches that overcome frequent detection limitations such as halos, noise, and droplet boundaries in microfluidic applications. Reconstructed cells are then discriminated between single cells and clusters of round-shaped cells, and cell information such as the area and location of a cell in an image is output. Using this method, 76% of cells detected in an image had an error <5% of the cell area size and 41% of the image had an error <1% of the cell area size (n=1,000). The method developed in the present study is the first image processing algorithm designed to be flexible in use (i.e. independent of the size of an image, using a microfluidic droplet system or not, and able to recognize cell clusters in an image) and provides the scientific community with a very accurate imaging algorithm in the field of microfluidic applications. (C) 2016 International Society for Advancement of Cytometry

    DOI PubMed

  • Predictive lethal proarrhythmic risk evaluation using a closed-loop-circuit cell network with human induced pluripotent stem cells derived cardiomyocytes

    Fumimasa Nomura, Akihiro Hattori, Hideyuki Terazono, Hyonchol Kim, Masao Odaka, Yoshihiro Sugio, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   55 ( 6 ) 06GN07-1 - 06GN07-5  2016.06  [Refereed]

    　View Summary

    For the prediction of lethal arrhythmia occurrence caused by abnormality of cell-to-cell conduction, we have developed a next-generation in vitro cell-to-cell conduction assay, i.e., a quasi in vivo assay, in which the change in spatial cell-to-cell conduction is quantitatively evaluated from the change in waveforms of the convoluted electrophysiological signals from lined-up cardiomyocytes on a single closed loop of a microelectrode of 1 mm diameter and 20 mu m width in a cultivation chip. To evaluate the importance of the closed-loop arrangement of cardiomyocytes for prediction, we compared the change in waveforms of convoluted signals of the responses in the closed-loop circuit arrangement with that of the response of cardiomyocyte clusters using a typical human ether a go-go related gene (hERG) ion channel blocker, E-4031. The results showed that (1) waveform prolongation and fluctuation both in the closed loops and clusters increased depending on the E-4031 concentration increase. However, (2) only the waveform signals in closed loops showed an apparent temporal change in waveforms from ventricular tachycardia (VT) to ventricular fibrillation (VF), which is similar to the most typical cell-to-cell conductance abnormality. The results indicated the usefulness of convoluted waveform signals of a closed-loop cell network for acquiring reproducible results acquisition and more detailed temporal information on cell-to-cell conduction. (C) 2016 The Japan Society of Applied Physics

    DOI

  • Particle recognition in microfluidic applications using a template matching algorithm

    Mathias Girault, Masao Odaka, Hyonchol Kim, Kenji Matsuura, Hideyuki Terazono, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   55 ( 6 ) 06GN05-1 - 06GN05-5  2016.06  [Refereed]

    　View Summary

    We herein examined the ability of a template matching algorithm to recognize particles with diameters ranging from 1 to 20 mu m in a microfluidic channel. The algorithm consisted of measurements of the distance between the templates and the images captured with a high-speed camera in order to search for the presence of the desired particle. The results obtained indicated that the effects of blur and diffraction rings observed around the particle are important phenomena that limit the recognition of a target. Owing to the effects of diffraction rings, the distance between a template and an image is not exclusively linked to the position of the focus plane; it is also linked to the size of the particle being searched for. By using a set of three templates captured at different Z focuses and an 800x magnification, the template matching algorithm has the ability to recognize beads ranging in diameter from 1.7 to 20 mu m with a resolution between 0.3 and 1 mu m. (C) 2016 The Japan Society of Applied Physics

    DOI

  • Development of a microprocessing-assisted cell-systematic evolution of ligands by exponential enrichment method for human umbilical vein endothelial cells

    Hideyuki Terazono, Hyonchol Kim, Fumimasa Nomura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   55 ( 6 ) 06GN03-1 - 06GN03-5  2016.06  [Refereed]

    　View Summary

    We developed a microprocessing-assisted technique to select single-strand DNA aptamers that bind to unknown targets on the cell surface by modifying the conventional systematic evolution of ligands by exponential enrichment (cell-SELEX). Our technique involves 1) the specific selection of target-cell-surface-bound aptamers without leakage of intracellular components by trypsinization and 2) cloning of aptamers by microprocessing-assisted picking of single cells using magnetic beads. After cell-SELEX, the enriched aptamers were conjugated with magnetic beads. The aptamer-magnetic beads conjugates attached to target cells were collected individually by microassisted procedures using microneedles under a microscope. After that, the sequences of the collected magnetic-bead-bound aptamers were identified. As a result, a specific aptamer for the surface of target cells, e.g., human umbilical vein endothelial cells (HUVECs), was chosen and its specificity was examined using other cell types, e.g., HeLa cells. The results indicate that this microprocessing-assisted cell-SELEX method for identifying aptamers is applicable in biological research and clinical diagnostics. (C) 2016 The Japan Society of Applied Physics

    DOI

  • A distribution analysis of action potential parameters obtained from patch-clamped human stem cell-derived cardiomyocytes

    Fernando Lopez-Redondo, Junko Kurokawa, Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Tetsushi Furukawa, Kenji Yasuda

    JOURNAL OF PHARMACOLOGICAL SCIENCES   131 ( 2 ) 141 - 145  2016.06  [Refereed]

    　View Summary

    We investigated electrophysiological properties of human induced-pluripotent-stem-cell-derived and embryonic-stem-cell-derived cardiomyocytes, and analyzed action potential parameters by plotting their frequency distributions. In the both cell lines, the distribution analysis revealed that histograms of maximum upstroke velocity showed two subpopulations with similar intersection values. Subpopulations with faster maximum upstroke velocity showed significant prolongation of action potential durations by application of E-4031, whereas others did not, which may be partly due to shallower maximum diastolic potentials. We described electrophysiological and pharmacological properties of stem-cell-derived cardiomyocytes in the respective sub-populations, which provides a way to characterize diverse electrical properties of stem-cell-derived cardiomyocytes systematically. (C) 2016 The Authors. Production and hosting by Elsevier B. V. on behalf of Japanese Pharmacological Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

    DOI PubMed

  • Contribution of Depletion Effect for Size-Selective Target Cell Acquisition in Cup-Shaped Microstructures

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    BIOPHYSICAL JOURNAL   110 ( 3 ) 168A - 168A  2016.02  [Refereed]

    DOI

  • Novel technology to assay the multicellular network: On-chip cellomics technology

    Kenji Yasuda

    Vascular Engineering: New Prospects of Vascular Medicine and Biology with a Multidiscipline Approach     333 - 393  2016.01

    　View Summary

    A series of studies aimed at developing methods and technologies of analyzing epigenetic information in cells and in those networks, as well as that of genetic information, was examined to expand our understanding of how living systems are determined. Technologies of analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an "algebraic" system (emphasis on temporal aspects) and as a "geometric" system (emphasis on spatial aspects). Exploiting the combination of latest microfabrication technologies and measurement technologies, which we call on-chip cellomics technology, we can select, control, and reconstruct the environments, interaction of single cells and cell networks from "algebraic" and "geometric" viewpoints. In this chapter, our developed technolgoeis and some results for spatial viewpoint of epigenetic information as a part of a series of cell-networkbased "geometric" studies of celluler systems in our research groups are summarized and reported. The knowlege and technolgies acquired from these viewpoints may lead to the use of cells that fully control practical applications like cell-network-based drug screening and the regeneration of organs from cells.

    DOI

  • Development of impedance/external field potential dual measurement system for evaluation of electrophysiological properties of cells on microelectrodes

    Fumimasa Nomura, Kenji Matsuura, Akihiro Hattori, Masao Odaka, Yoshihiro Sugio, Hiromi Kurotobi, Hideyuki Terazono, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 6 ) 06FN06-1 - 06FN06-4  2015.06  [Refereed]

    　View Summary

    A combination of extracellular field potential (FP) and impedance measurement technologies for multielectrode array (MEA) chip architecture is developed for the simultaneous evaluation of information on the ion current and resistance of cells and microelectrodes. The simultaneous measurement system can not only evaluate the time course changes of characteristics in the MEAs but also clarification of the origin of the difference in the waveform of the field potentials of each cell on an microelectrode whether it is caused by the changes in the electrophysiological properties of cells or by the changes in the performance of an microelectrode (and cell-to-electrode contacts). The automatic impedance measurement technology in the system exploited the swiping of the wide frequency range of impedances of microelectrodes and calculated the true impedance of each microelectrode without significant effects on the cells on the MEA chip. Hence, the system can give us invisible cell-to-electrode contact information and its change, and also information on the degradation of the performance of microelectrodes during long-term cultivation and after the application of compounds into the MEA chip. The impedance spectrum measurement showed that (1) the increase in the impedance of microelectrodes correlated with its area decrease from 10% 7 to 10% 10m(2), (2) even the area of microelectrodes decreased from 10% 8 to 10% 10m(2), the noise level of field potential signals was independent and did not change, and (3) the attachment of cells on the microelectrode surface can be determined by a significant increase in impedance at 1 kHz corresponding to the width of the depolarization peak on the field potential recordings. These results indicate the potential to evaluate the cell-to-electrode contact and degradation of microelectrodes, which was not evaluated in conventional FP measurements only. These results also indicate that this method should be used for the evaluation of the changes in cell network conditions caused by various compounds. (C) 2015 The Japan Society of Applied Physics

    DOI

  • Depletion effect on concave microstructure upon size-specific target particle collection

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 6 ) 06FL02-1 - 06FL02-5  2015.06

    　View Summary

    The depletion effect on a concave microstructure for size-specific target particle collection was evaluated using a set of strictly size-controlled superparamagnetic hemispheres, "magcups", with mixtures of differently sized model target microbeads in the presence of dispersed polystyrene nanoparticles (PS-NPs), which are thought to enhance entropic depletion effects to capture model target beads having the size closest to those of the hemispherical microstructures of magcups. Magcups with diameters of 10 to 50 mu m were fabricated with the formation of three nickel layers (2nm thickness) inserted between silicon dioxide layers (15 nm) on polystyrene template spheres by vapor deposition and subsequent polystyrene removal by burning. Two different diameters of model target beads (10 and 20 mu m) were mixed with the magcups in order to evaluate the contribution of the depletion effect to the frequency of target bead capture by the concave microstructures of magcups of various sizes. To evaluate the depletion effect caused by the presence of dispersed PS-NPs, we compared the frequencies of target bead-magcup conjugations with and without PS-NPs in reaction solvents, and found that (i) the frequency of 10-mu m-diameter bead capture increased 3.0 times on average for 15- and 20-mu m-diameter magcups, and (ii) the frequencies of 10-mu m-diameter beads capture increased as almost the same level with that of 20-mu m bead for 30-, 40-, and 50-mu m-diameter magcups. These results suggest that conjugations of target beads with magcups were encouraged by the depletion effect due to the presence of PS-NPs. (C) 2015 The Japan Society of Applied Physics

    DOI

  • Evaluation of imaging biomarkers for identification of single cancer cells in blood

    Masao Odaka, Hyonchol Kim, Mathias Girault, Akihiro Hattori, Hideyuki Terazono, Kenji Matsuura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 6 ) 06FN04-1 - 06FN04-6  2015.06

    　View Summary

    A method of discriminating single cancer cells from whole blood cells based on their morphological visual characteristics (i.e., "imaging biomarker") was examined. Cells in healthy rat blood, a cancer cell line (MAT-LyLu), and cells in cancer-cell-implanted rat blood were chosen as models, and their bright-field (BF, whole-cell morphology) and fluorescence (FL, nucleus morphology) images were taken by an on-chip multi-imaging flow cytometry system and compared. Eight imaging biomarker indices, i.e., cellular area in a BF image, nucleus area in an FL image, area ratio of a whole cell and its nucleus, distance of the mass center between a whole cell and nucleus, cellular and nucleus perimeter, and perimeter ratios were calculated and analyzed using the BF and FL images taken. Results show that cancer cells can be clearly distinguished from healthy blood cells using correlation diagrams for cellular and nucleus areas as two different categories. Moreover, a portion of cancer cells showed a low nucleus perimeter ratio less than 0.9 because of the irregular nucleus morphologies of cancer cells. These results indicate that the measurements of imaging biomarkers are practically applicable to identifying cancer cells in blood. (C) 2015 The Japan Society of Applied Physics

    DOI

  • Toward quasi-in vivo from in vitro assay (III): Noninvasive identification and purification method of target cardiomyocyte cells using nuclease digestive magnetic-beads-attached ssDNA aptamers

    Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori, Tomoyo Hamada, Fumimasa Nomura, Kenji Yasuda

    JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS   70 ( 3 ) 322 - 323  2014.11  [Refereed]

    DOI

  • Toward quasi-in vivo from in vitro assay (IV): Fabrication of direction-controlled artificial neuronal networks using agarose-microetching method and single-cell-electrodes for quantitative evaluation of neuropsychiatric disorders

    Hideyuk Terazono, Hyonchol Kim, Akihiro Hattori, Fumimasa Nomura, Tomoyo Hamada, Kenji Yasuda

    JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS   70 ( 3 ) 348 - 348  2014.11  [Refereed]

    DOI

  • Cup-Shaped Superparamagnetic Hemispheres for Size-Selective Cell Filtration

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    SCIENTIFIC REPORTS   4 ( 1 ) 6362  2014.09  [Refereed]

    　View Summary

    We propose a new method of size separation of cells exploiting precisely size-controlled hemispherical superparamagnetic microparticles. A three-layered structure of a 2-nm nickel layer inserted between 15-nm silicon dioxide layers was formed on polystyrene cast spheres by vapor deposition. The polystyrene was then removed by burning and the hemispherical superparamagnetic microparticles, "magcups", were obtained. The standard target cells (CCRF-CEM, 12 +/- 62 mu m) were mixed with a set of different sizes of the fabricated magcups, and we confirmed that the cells were captured in the magcups having cavities larger than 15 mu m in diameter, and then gathered by magnetic force. The collected cells were grown in a culture medium without any damage. The results suggest that this method is quick, simple and non-invasive size separation of target cells.

    DOI PubMed

  • Development of On-Chip Multi-Imaging Flow Cytometry for Identification of Imaging Biomarkers of Clustered Circulating Tumor Cells

    Hyonchol Kim, Hideyuki Terazono, Yoshiyasu Nakamura, Kazuko Sakai, Akihiro Hattori, Masao Odaka, Mathias Girault, Tokuzo Arao, Kazuto Nishio, Yohei Miyagi, Kenji Yasuda

    PLOS ONE   9 ( 8 ) e104372  2014.08  [Refereed]

    　View Summary

    An on-chip multi-imaging flow cytometry system has been developed to obtain morphometric parameters of cell clusters such as cell number, perimeter, total cross-sectional area, number of nuclei and size of clusters as "imaging biomarkers'', with simultaneous acquisition and analysis of both bright-field (BF) and fluorescent (FL) images at 200 frames per second (fps); by using this system, we examined the effectiveness of using imaging biomarkers for the identification of clustered circulating tumor cells (CTCs). Sample blood of rats in which a prostate cancer cell line (MAT-LyLu) had been pre-implanted was applied to a microchannel on a disposable microchip after staining the nuclei using fluorescent dye for their visualization, and the acquired images were measured and compared with those of healthy rats. In terms of the results, clustered cells having (1) cell area larger than 200 mu m(2) and (2) nucleus area larger than 90 mu m(2) were specifically observed in cancer cell-implanted blood, but were not observed in healthy rats. In addition, (3) clusters having more than 3 nuclei were specific for cancer-implanted blood and (4) a ratio between the actual perimeter and the perimeter calculated from the obtained area, which reflects a shape distorted from ideal roundness, of less than 0.90 was specific for all clusters having more than 3 nuclei and was also specific for cancer-implanted blood. The collected clusters larger than 300 mu m(2) were examined by quantitative gene copy number assay, and were identified as being CTCs. These results indicate the usefulness of the imaging biomarkers for characterizing clusters, and all of the four examined imaging biomarkers-cluster area, nuclei area, nuclei number, and ratio of perimeter-can identify clustered CTCs in blood with the same level of preciseness using multi-imaging cytometry.

    DOI PubMed

  • Optical trapping techniques in bioanalysis

    Kenji Yasuda

    Biomedical Photonics Handbook     457 - 491  2014.07

    　View Summary

    Knowledge of life has expanded dramatically during the twentieth century and has produced the modern disciplines of genomics and proteomics. However, there remains the great challenge of discovering the integration and regulation of these living components in time and space within the cell. As we move into the postgenomic period, the complementarity between genomics and proteomics will become apparent, and the connections between them will be exploited, although, neither genomics, proteomics, nor, for that matter, their simple combination will provide the data necessary to interconnect molecular events in living cells in time and space. e cells in a group are dierent entities. Each of them respond to the perturbations dierently (Spudich and Koshland 1976). e dierences between cells arise even among those grown in homogeneous conditions and considered to have identical genetic information. Why and how do these dierences arise? ey might be caused by several factors like unequal distributions of biomolecules in cells, mutations, interactions between cells, and uctuations of environmental elements. A system that can observe interactions between specic cells continuously under fully controlled.

    DOI

  • Identification of cells using morphological information of bright field/fluorescent multi-imaging flow cytometer images

    Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Masao Odaka, Mathias Girault, Kenji Matsuura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 6 ) 06JL03-1 - 06JL03-4  2014.06  [Refereed]

    　View Summary

    We have examined the ability of real-time simultaneous measurement of bright field/fluorescent images of cells in an on-chip bright field/fluorescent multi-imaging flow cytometer system. The system consists of (1) a disposable microfluidic hydrofocusing flow cytometry chip, (2) an optical microscopy module with splittable bright field/fluorescent multi-imaging optics, and (3) a real-time image-processing module with a 200 images/s high-speed digital camera. In the double "Y" shape three-way-inlet microfluidic pathways fabricated in the poly(dimethylsiloxane) (PDMS) microchip, we applied fluorescent polystyrene standard beads and HeLa cells stained with fluorescent dye, Hoechst 33258, and measured the z-axis (depth) dependence of the morphological index; the intensity profile of cells and nuclei. Then, we measured the tendency of the blur of bright field/fluorescent images in the simultaneous measurement of bright field/fluorescent images on a single light-receiving surface, and found that their blurs were similar within the same range of the depth of the microfluidic pathway for small cell cluster measurement, 25 m. Hence, the fluorescent images were applied as supporting information of the bright field images of cell clusters at the focal plane for the cell number counting. The result indicates the potential of precise identification of various types of cells by simultaneous morphological analysis of bright field and fluorescent images distributed with a single camera in a wider depth of microfluidic chip as a substitute for conventional biomarker detection. (C) 2014 The Japan Society of Applied Physics

    DOI

  • Fabrication of multilayered superparamagnetic particles based on sequential thermal deposition method

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 6 ) 06JJ01-1 - 06JJ01-6  2014.06  [Refereed]

    　View Summary

    A simple method for the fabrication of superparamagnetic particles was developed. Polystyrene spheres were used as templates, and their surfaces were coated with a magnetic element (Ni) by thermal deposition, controlling their thicknesses strictly. Magnetic properties of fabricated particles depended on the Ni layer thickness; the fabricated particles were typically superparamagnetic for a Ni layer thinner than 3 nm and ferromagnetic for a Ni layer thicker than 4 nm. For the improvement of the force generated on a particle in a magnetic field, the formation of multiple Ni layers on a particle was examined by sequential depositions of Ni and SiO2, isolating two Ni layers with a SiO2 layer. The SiO2 layer thickness should be larger than 10 nm for a sufficient isolation of two Ni layers to maintain the superparamagnetic properties of the particle, and the magnetic charge of the particle increased proportionally with the number of Ni layers on a particle. These results indicate that enhanced superparamagnetic particles with various diameters can easily be fabricated by the suggested method. (C) 2014 The Japan Society of Applied Physics

    DOI

  • Homogenous measurement during a circulation-water-based ultrahigh-speed polymerase chain reaction and melting curve analysis device

    Hideyuki Terazono, Kenji Matsuura, Hyonchol Kim, Hiroyuki Takei, Akihiro Hattori, Fumimasa Nomura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 6 ) 06JM08-1 - 06JM08-5  2014.06  [Refereed]

    　View Summary

    Polymerase chain reaction (PCR) is an essential technique for almost all life science fields that amplifies few target DNA copies. We developed a rapid real-time microdroplet PCR device by rapid switching of two types of circulation hot water, a mu L-sized droplet, and a thin film aluminum chip. Using this device, rapid PCR amplification was observed successfully and accomplished within 3min. By real-time PCR, many samples could be measured simultaneously. Moreover, melting curve analysis is essential for detecting differences of PCR amplicons in detail such as those related to nonspecific amplification, single nucleotide polymorphism, and genotyping methods. Thus, we developed a device that can be used for melting curve analysis using circulation water. From the obtained results, temperature homogeneity on the reaction plate was maintained during PCR and melting curve analysis using high-speed circulation water. The results indicate that this system can be applied to various life science fields. (C) 2014 The Japan Society of Applied Physics

    DOI

  • On-chip in vitro cell-network pre-clinical cardiac toxicity using spatiotemporal human cardiomyocyte measurement on a chip

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Yasuyuki Abe, Hideo Takamori, Tomoko Sakakura, Kiyoshi Takasuna, Atsushi Sanbuissho, Johan Hyllner, Peter Sartipy, Kenji Yasuda

    SCIENTIFIC REPORTS   4 ( 1 ) 4670  2014.04  [Refereed]

    　View Summary

    To overcome the limitations and misjudgments of conventional prediction of arrhythmic cardiotoxicity, we have developed an on-chip in vitro predictive cardiotoxicity assay using cardiomyocytes derived from human stem cells employing a constructive spatiotemporal two step measurement of fluctuation (short-term variability; STV) of cell's repolarization and cell-to-cell conduction time, representing two origins of lethal arrhythmia. Temporal STV of field potential duration (FPD) showed a potential to predict the risks of lethal arrhythmia originated from repolarization dispersion for false negative compounds, which was not correctly predicted by conventional measurements using animal cells, even for non-QT prolonging clinical positive compounds. Spatial STV of conduction time delay also unveiled the proarrhythmic risk of asynchronous propagation in cell networks, whose risk cannot be correctly predicted by single-cell-based measurements, indicating the importance of the spatiotemporal fluctuation viewpoint of in vitro cell networks for precise prediction of lethal arrhythmia reaching clinical assessment such as thorough QT assay.

    DOI PubMed

  • 【細胞の3次元組織化-その最先端技術と材料技術 再生医療とその支援分野(細胞研究、創薬研究)への応用と発展のために】(第3章)細胞3次元組織化のための培養技術 MEMS技術 創薬研究ツール

    安田 賢二, 野村 典正, 寺薗 英之, 服部 明弘

    遺伝子医学MOOK   別冊 ( 細胞の3次元組織化-その最先端技術と材料技術 ) 216 - 222  2014.02

    　View Summary

    ヒトiPS細胞の出現によって創薬スクリーニング法もヒト細胞を用いたものが検討されている。特に最も分化誘導技術の開発が進んでいるヒト心筋細胞については,実際の致死性不整脈を引き起こす「興奮伝導異常」を計測するオンチップ計測技術を用いることで,(1)細胞のカリウムイオンチャネルの応答のゆらぎ解析による安定性変化の定量化(時間的観点),(2)心筋細胞ネットワークでの伝達状態のゆらぎ解析による伝達異常の定量化(空間的観点)によって,従来の計測法で偽陰性・偽陽性と評価されてきた候補薬の催不整脈リスクを正確に計測することが可能となりつつある。(著者抄録)

  • DNA Hybridization Efficiency on Concave Surface Nano-Structure in Hemispherical Janus Nanocups

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    LANGMUIR   30 ( 5 ) 1272 - 1280  2014.02  [Refereed]

    　View Summary

    We examined the effect of a concave structure on DNA hybridization efficiency using an inner surface of hemispherical Janus nanocups in the range from 140 to 800 nm. Target DNA was specifically immobilized onto the inner cup surface, hybridized with complementary DNA-attached 20 nm Au probes, and the number of the hybridized probes was counted by scanning electron microscopy. The hybridization density of the attached Au probes on 800 nm nanocups was 255 mu m(-2), which was 0.57 times that on a flat surface, 449 mu m(-2), and increased to 394 mu m(-2) on a 140 nm cup, 0.88 times of a flat surface, as the cup size decreased. The local density of attached Au probes within the central 25% at the bottom of the 800 nm nanocups was 444 mu m(-2), which was closer to that on a flat surface, and the tendency was the same for all sizes of cups, indicating that the size dependency of DNA hybridization efficiency on the concave structures were mostly affected by the lower efficiency of side wall hybridization.

    DOI PubMed

  • 2P318 Investigation of wide range optical set-up for simultaneous realtime analysis of 96-well SBS formatted samples(28. Bioengineering,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Hattori Akihiro, Terazono Hideyuki, Matsuura Kenji, Kim Hyonchol, Odaka Masao, Girault Mathias, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S247  2014

    DOI CiNii

  • 2P289 Optimization of the cell encapsulation in the water in oil droplet using 3D printed object(26. Measurements,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Girault Mathias, Hattori Akihiro, Kim Hyonchol, Matsuura Kenji, Odaka Masao, Mikami Yumi, Terazono Hideyuki, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S243  2014

    DOI CiNii

  • 2P316 A temperature-control technique with great accuracy and uniformity for a ANSI/SBS plate for 3-min PCR and a melting curve analysis(28. Bioengineering,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Terazono Hideyuki, Kim Hyonchol, Matsuura Kenji, Hattori Akihiro, Nomura Fumimasa, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S247  2014

    DOI CiNii

  • 2P294 Non-firing impedance-based electrophysiological analysis of single cells on micro-electrode arrays(26. Measurements,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Matsuura Kenji, Hattori Akihiro, Nomura Fumimasa, Terazono Hideyuki, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S243  2014

    DOI CiNii

  • 2P287 Development of the cell imaging biomarker identification algorism for on-chip multi imaging cell sorter system(26. Measurements,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Odaka Masao, Kim Hyonchol, Girault Mathias, Hattori Akihiro, Terazono Hideyuki, Matsuura Kenji, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S242  2014

    DOI CiNii

  • 2P288 Imaging biomarkers for identification of target cells: Identification of clustered circulating tumor cells as an example(26. Measurements,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Kim Hyonchol, Terazono Hideyuki, Hattori Akihiro, Odaka Masao, Girault Mathias, Yasuda Kenji

    Seibutsu Butsuri   54 ( 1 ) S242  2014

    DOI CiNii

  • Temperature-Shift Speed Dependence of Nonspecific Amplification of Polymerase Chain Reaction Examined by 1480 nm Photothermal Transition Speed Controllable High-Speed Polymerase Chain Reaction System

    Hideyuki Terazono, Akihiro Hattori, Hyonchol Kim, Hiroyuki Takei, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    Japanese Journal of Applied Physics   52 ( 6S )  2013.06

    　View Summary

    We have examined the contribution of temperature shift speed from denaturation to extension for the reduction of nonspecific amplification caused by the mismatched primer-target attachment. We have newly developed the photothermal quantitative polymerase chain reaction (qPCR) system, in which the direct absorption of a 1480nm infrared laser beam was controlled by a rotating gradient neutral density (ND) filter to acquire the precise control of the desired speed of temperature shift between 60 and 95°C up to 1 s. The results showed that a quick shift of the temperature during the qPCR procedure reduced nonspecific amplicons with a significant reduction of qPCR time when we have chosen proper primer sets, whereas the non-proper primer set amplified nonspecific amplicons in the fast qPCR. The results indicate that the potential of quick qPCR using proper primers can reduce nonspecific amplification and the required time for qPCR measurement, and the necessity of more precise check of the matching of the primer template adequate for the fast temperature shift and for quick qPCR analysis. © 2013 The Japan Society of Applied Physics.

    DOI

  • Non-destructive on-chip imaging flow cell-sorting system for on-chip cellomics

    Kenji Yasuda, Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Tomoyuki Kaneko, Fumimasa Nomura

    MICROFLUIDICS AND NANOFLUIDICS   14 ( 6 ) 907 - 931  2013.06

    　View Summary

    We have developed a non-destructive imaging flow cell-sorting system using an ultra-high-speed camera (shutter speed of 1/10,000 s) with a real-time image analysis unit and a poly(methyl methacrylate) (PMMA)-based disposable microfluidic chip for single-cell-based on-chip cellomics. It has a 3-D micropipetting device that supports fully automated sorting and collection of samples. The entire fluidic system is implemented in a disposable plastic chip, enabling biological samples to be lined up in a laminar flow using hydrodynamic focusing. Its optical system enables direct observation-based cell identification using specific image indexes and phase-contrast/fluorescence microscopy, real-time image processing. It has a non-destructive, wider dynamic range, sorting procedure using mild electrostatic force in a laminar flow; agarose gel electrodes are used to prevent electrode loss and electrolysis bubble formation. The microreservoir used for recultivating collected target cells is contamination-free. An integrated ultra-high-speed droplet polymerase chain reaction measurement module is used for DNA/mRNA analysis of the collected target cells. This system was used to separate cardiomyocyte cells from a mixture of various cells. All the operations were automated using the 3-D micropipetting device. The results demonstrate that this imaging flow cell-sorting system is practically applicable for biological research and clinical diagnosis.

    DOI

  • Advanced ring-shaped microelectrode assay combined with small rectangular electrode for quasi-in vivo measurement of cell-to-cell conductance in cardiomyocyte network

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    Japanese Journal of Applied Physics   52 ( 6 ) 06GK07-1 - 06GK07-7  2013.06

    　View Summary

    To predict the risk of fatal arrhythmia induced by cardiotoxicity in the highly complex human heart system, we have developed a novel quasiin vivo electrophysiological measurement assay, which combines a ring-shaped human cardiomyocyte network and a set of two electrodes that form a large single ring-shaped electrode for the direct measurement of irregular cell-to-cell conductance occurrence in a cardiomyocyte network, and a small rectangular microelectrode for forced pacing of cardiomyocyte beating and for acquiring the field potential waveforms of cardiomyocytes. The advantages of this assay are as follows. The electrophysiological signals of cardiomyocytes in the ring-shaped network are superimposed directly on a single loop-shaped electrode, in which the information of asynchronous behavior of cell-to-cell conductance are included, without requiring a set of huge numbers of microelectrode arrays, a set of fast data conversion circuits, or a complex analysis in a computer. Another advantage is that the small rectangular electrode can control the position and timing of forced beating in a ring-shaped human induced pluripotent stem cell (hiPS)-derived cardiomyocyte network and can also acquire the field potentials of cardiomyocytes. First, we constructed the human iPS-derived cardiomyocyte ring-shaped network on the set of two electrodes, and acquired the field potential signals of particular cardiomyocytes in the ring-shaped cardiomyocyte network during simultaneous acquisition of the superimposed signals of wholecardiomyocyte networks representing cell-to-cell conduction. Using the small rectangular electrode, we have also evaluated the response of the cell network to electrical stimulation. The mean and SD of the minimum stimulation voltage required for pacing (VMin) at the small rectangular electrode was 166 ± 74 mV, which is the same as the magnitude of amplitude for the pacing using the ring-shaped electrode (179 33 mV). The results showed that the addition of a small rectangular electrode into the ring-shaped electrode was effective for the simultaneous measurement of whole-cell-network signals and single-cell/small-cluster signals on a local site in the cell network, and for the pacing by electrical stimulation of cardiomyocyte networks. © 2013 The Japan Society of Applied Physics.

    DOI

  • Physiological Sample Uniformity and Time-Course Stability in Lined-Up Structure of Human Cardiomyocyte Network for In vitro Predictive Drug-Induced Cardiotoxicity

    Tomoyo Hamada, Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   52 ( 6 ) 06GK05-1 - 06GK05-6  2013.06  [Refereed]

    　View Summary

    We have evaluated the electrophysiological characteristics of a line-shaped network of a three-dimensionally controlled in vitro human cardiomyocyte assay (hCM line) against conventional cell clusters as the standard model (hCM cluster) from the viewpoint of quality control of sample variety and time-course stability. The beating intervals of the hCM line demonstrated a more stable uniformity of samples (846 +/- 130 ms, 15.3% fluctuation) and better time-course stability, whereas those of the hCM cluster showed a much larger variety of samples (2001 +/- 1127 ms, 56.3% fluctuation) and weaker time-course stability. The field potential amplitude of the hCM line also showed better uniformity of samples (629 +/- 428 mu V, 68.0% fluctuation) against those of the hCM cluster (1984 +/- 2288 mu V, 115.3% fluctuation). The results suggested the importance of the cell-network shape control for the uniformity and stability of the beating interval and the field potential amplitude. They also suggest that the hCM line can improve the reproducibility and accuracy of the samples, which is important for a functional human cardiotoxicity model. (C) 2013 The Japan Society of Applied Physics

    DOI

  • On-Chip Single-Cell-Shape Control Technology for Understanding Contractile Motion of Cardiomyocytes Measured Using Optical Image Analysis System

    Tomoyuki Kaneko, Eikei Takizawa, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   52 ( 6 ) 06GK06-1 - 06GK06-5  2013.06  [Refereed]

    　View Summary

    Quantitative evaluation of mechanophysiological responses of cardiomyocytes has become more important for more precise prediction of cardiotoxicity. For the accurate detection of cardiomyocyte contraction, we have developed an on-chip single-cell-shape control technology on the basis of an agarose microchamber system and an on-chip optical image analysis system that records the contractile motions of cardiomyocytes with noninvasive/nondestructive measurement for long-term experiments. Using this on-chip single-cell-shape control technology, the shape of single cardiomyocytes was controlled by seeding the cells in 21-mu m-radius (circular) or 20 x 70 mu m(2) (rectangular) agarose microchambers. To detect the contractility of cardiomyocytes, the cells were labeled with microbeads attached onto the surface of target cells and the motion of beads was acquired and analyzed using a newly developed wider-depth-of-field optics equipped with a 1/100 s high-speed digital camera. Mechanophysiological properties such as displacement and direction of movement were obtained using a real-time processing system module at spatial and temporal resolutions of 0.15 mu m and 10 ms, respectively. Comparisons of displacement and direction of contraction between circular and rectangular cardiomyocytes indicated that the rectangular cardiomyocytes tended to contract along the longitudinal direction as in a real heart. This result suggests that the shape of cells affected the function of cells. The on-chip single-cell-shape control technology and optical image analysis system enable the detection of the motion of contraction of single-shape-controlled cardiomyocytes, and are expected to be applicable to the more precise prediction of cardiotoxicity. (C) 2013 The Japan Society of Applied Physics

    DOI

  • Microtechnologies to fuel neurobiological research with nanometer precision

    Cecilia A. Brunello, Ville Jokinen, Prasanna Sakha, Hideyuki Terazono, Fumimasa Nomura, Tomoyuki Kaneko, Sari E. Lauri, Sami Franssila, Claudio Rivera, Kenji Yasuda, Henri J. Huttunen

    JOURNAL OF NANOBIOTECHNOLOGY   11 ( 1 ) 11 - 11  2013.04  [Refereed]

    　View Summary

    The interface between engineering and molecular life sciences has been fertile ground for advancing our understanding of complex biological systems. Engineered microstructures offer a diverse toolbox for cellular and molecular biologists to direct the placement of cells and small organisms, and to recreate biological functions in vitro: cells can be positioned and connected in a designed fashion, and connectivity and community effects of cells studied. Because of the highly polar morphology and finely compartmentalized functions of neurons, microfabricated cell culture systems and related on-chip technologies have become an important enabling platform for studying development, function and degeneration of the nervous system at the molecular and cellular level. Here we review some of the compartmentalization techniques developed so far to highlight how high-precision control of neuronal connectivity allows new approaches for studying axonal and synaptic biology.

    DOI PubMed

  • Exploring the implicit interlayer regulatory mechanism between cells and tissue: Stochastic mathematical analyses of the spontaneous ordering in beating synchronization

    Hiroyuki Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda, Masahiro Okamoto

    BIOSYSTEMS   111 ( 3 ) 208 - 215  2013.03  [Refereed]

    　View Summary

    The present study focused on beating synchronization, and tried to elucidate the interlayer regulatory mechanisms between the cells and clump in beating synchronization with using the stochastic simulations which realize the beating synchronizations in beating cells with low cell-cell conductance. Firstly, the fluctuation in interbeat intervals (IBIs) of beating cells encouraged the process of beating synchronization, which was identified as the stochastic resonance. Secondly, fluctuation in the synchronized IBIs of a clump decreased as the number of beating cells increased. The decrease in IBI fluctuation due to clump formation implied both a decline of the electrophysiological plasticity of each beating cell and an enhancement of the electrophysiological stability of the clump. These findings were identified as the community effects. Because IBI fluctuation and the community effect facilitated the beating stability of the cell and clump, these factors contributed to the spontaneous ordering in beating synchronization. Thirdly, the cellular layouts in clump affected the synchronized beating rhythms. The synchronized beating rhythm in clump was implicitly regulated by a complicated synergistic effect among IBI fluctuation of each beating cell, the community effect and the cellular layout. This finding was indispensable for leading an elucidation of mechanism of emergence. The stochastic simulations showed the necessity of considering the synergistic effect, to elucidate the interlayer regulatory mechanisms in biological system. (C) 2013 Elsevier Ireland Ltd, All rights reserved.

    DOI PubMed

  • 1P308 Real time image analysis technology for identification and collection of clustered cells using on-chip multi-imaging cell sorter(28. Bioengineering,Poster)

    Odaka Masao, Girault Mathias, Kim Hyonchol, Terazono Hideyuki, Hattori Akihiro, Yasuda Kenji

    Seibutsu Butsuri   53 ( 1 ) S157  2013

    DOI CiNii

  • 1P316 Development of On-chip Multi-imaging Flow Cytometer System using Real-time Bright Field/Fluorescent Dual Image Analysis High-speed Camera(28. Bioengineering,Poster)

    Hattori Akihiro, Kim Hyonchol, Terazono Hideyuki, Odaka Masao, Girault Mathias, Yasuda Kenji

    Seibutsu Butsuri   53 ( 1 ) S158  2013

    DOI CiNii

  • 3P310 Non-invasive identification and purification method of target cardiomyocyte cells using cell-surface-binding ssDNA aptamers(28.Bioengineering,Poster,The 51st Annual Meeting of the Biophysical Society of Japan)

    Terazono Hideyuki, Kim Hyonchol, Nomura Fumimasa, Yasuda Kenji

    Seibutsu Butsuri   53 ( 1 ) S263  2013

    DOI CiNii

  • 3P309 Fabrication of Superparamagnetic Metal Cups for Size-Selective Cell Collection(28.Bioengineering,Poster,The 51st Annual Meeting of the Biophysical Society of Japan)

    Kim Hyonchol, Terazono Hideyuki, Takei Hiroyuki, Yasuda Kenji

    Seibutsu Butsuri   53 ( 1 ) S263  2013

    DOI CiNii

  • Development of Adaptive SEM Technology for Genome/Proteome Expression Analysis in Single Cell Level

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    BIOPHYSICAL JOURNAL   104 ( 2 ) 675A - 675A  2013.01  [Refereed]

    DOI

  • Label-Free Shape-Based Selection of Cardiomyocytes with on-Chip Imaging Cell Sorting System

    Fumimasa Nomura, Tomoyuki Kaneko, Akihiro Hattori, Kenji Yasuda

    Journal of Bioprocessing & Biotechniques   03 ( 01 )  2013  [Refereed]

    DOI

  • Temperature-Shift Speed Dependence of Nonspecific Amplification of Polymerase Chain Reaction Examined by 1480 nm Photothermal Transition Speed Controllable Ultra-High-Speed Polymerase Chain Reaction System

    H. Terazono, A. Hattori, H. Kim, H. Takei, F. Nomura, K. Yasuda

    MOLECULAR BIOLOGY OF THE CELL   24 ( 6 ) 06GK02-1 - 06GK02-4  2013  [Refereed]

    DOI

  • On-chip cellomics: Single-cell-based constructive cell-network assay for quasi-in vivo screening of cardiotoxicity

    Kenji Yasuda

    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS   2013   2825 - 2828  2013

    　View Summary

    We have developed methods and systems of analyzing epigenetic information in cells, as well as that of genetic information, to expand our understanding of how living systems are determined. A system of analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an 'algebraic' system (emphasis on temporal aspects) and as a 'geometric' system (emphasis on spatial aspects). As an example of the 'geometric' system, we have developed an quasi-in vivo hiPS cardiomyocyte network assay and confirmed that it can predict the risk of lethal arrythmia correctly in 22 compounds. The knowlege acquired from this study may lead to the use of cells that fully control practical applications like cell-based drug screening and the regeneration of organs. © 2013 IEEE.

    DOI PubMed

  • On-Chip Cellomics: Constructive Understanding of Multicellular Network Using On-Chip Cellomics Technology

    Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 8 ) 08KA03  2012.08  [Refereed]

    　View Summary

    We have developed methods and systems of analyzing epigenetic information in cells to expand our understanding of how living systems are determined. Because cells are minimum units reflecting epigenetic information, which is considered to map the history of a parallel-processing recurrent network of biochemical reactions, their behaviors cannot be explained by considering only conventional deonucleotide (DNA) information-processing events. The role of epigenetic information on cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behaviour observed under conditions chosen to reveal adaptation processes and community effects. A system of analyzing epigenetic information, on-chip cellomics technology, has been developed starting from the twin complementary viewpoints of cell regulation as an "algebraic'' system (emphasis on temporal aspects) and as a "geometric'' system (emphasis on spatial aspects) exploiting microfabrication technology and a reconstructive approach of cellular systems not only for single cell-based subjects such as Escherichia coli and macrophages but also for cellular networks like the community effect of cardiomyocytes and plasticity in neuronal networks. One of the most important contributions of this study was to be able to reconstruct the concept of a cell regulatory network from the "local'' (molecules expressed at certain times and places) to the "global'' (the cell as a viable, functioning system). Knowledge of epigenetic information, which we can control and change during cell lives, complements the genetic variety, and these two types of information are indispensable for living organisms. This new knowlege has the potential to be the basis of cell-based biological and medical fields such as those involving cell-based drug screening and the regeneration of organs from stem cells. (C) 2012 The Japan Society of Applied Physics

    DOI

  • A Non-Destructive Culturing and Cell Sorting Method for Cardiomyocytes and Neurons Using a Double Alginate Layer

    Hideyuki Terazono, Hyonchol Kim, Masahito Hayashi, Akihiro Hattori, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    PLOS ONE   7 ( 8 ) e42485  2012.08

    　View Summary

    A non-destructive method of collecting cultured cells after identifying their in situ functional characteristics is proposed. In this method, cells are cultivated on an alginate layer in a culture dish and released by spot application of a calcium chelate buffer that locally melts the alginate layer and enables the collection of cultured cells at the single-cell level. Primary hippocampal neurons, beating human embryonic stem (hES) cell-derived cardiomyocytes, and beating hES cell-derived cardiomyocyte clusters cultivated on an alginate layer were successfully released and collected with a micropipette. The collected cells were recultured while maintaining their physiological function, including beating, and elongated neurites. These results suggest that the proposed method may eventually facilitate the transplantation of ES- or iPS-derived cardiomyocytes and neurons differentiated in culture.

    DOI PubMed

  • Contribution of metal layer thickness for quantitative backscattered electron imaging of field emission scanning electron microscopy

    Hyonchol Kim, Hiroyuki Takei, Tsutomu Negishi, Masato Kudo, Hideyuki Terazono, Kenji Yasuda

    e-Journal of Surface Science and Nanotechnology   10   301 - 304  2012.06

    　View Summary

    The contributions of metal thickness and the diameter of metal shell particles to quantitative backscattered electron (BSE) imaging in field emission scanning electron microscopy (FE-SEM) were studied to evaluate the potential of using these particles as simultaneously distinguishable labels of target molecules in FE-SEM studies. Gold spherical shells were fabricated with 200 or 300 nm diameter and 5, 10, 15 or 20 nm Au shell thickness, placed on silicon substrates, respectively, and observed in BSE imaging mode by FE-SEM. Flat Au films of the same thicknesses were formed on a Si substrate to evaluate the contribution of shell diameter to BSE imaging. The relationship between relative BSE intensity, which was calculated by setting the intensities of the Si substrate and 20 nm-thick Au layer as standards, and Au layer thickness was studied for all samples. With increasing Au layer thickness, BSE intensity also proportionally increased for all samples (R 2 &gt
    0.93) in the range of these thicknesses. Gradients of the increase were 1.5 times different between the flat film and metal shells, which was caused by the presence of voids in shell particles. The difference in gradients for increasing shell thickness between 200 and 300 nm particles was 15%. This result indicated that 1.5 times difference in shell diameter contributed to the increase of BSE intensity against the increase of shell thicknesses as a 15% error, and strict control of both metal shell diameter and thickness in the fabrication process is essential when using these shells as labels of BSE measurements in FE-SEM. © 2012 The Surface Science Society of Japan.

    DOI

  • On-Chip Cellomics Assay Enabling Algebraic and Geometric Understanding of Epigenetic Information in Cellular Networks of Living Systems. 1. Temporal Aspects of Epigenetic Information in Bacteria

    Kenji Yasuda

    SENSORS   12 ( 6 ) 7169 - 7206  2012.06  [Refereed]

    　View Summary

    A series of studies aimed at developing methods and systems of analyzing epigenetic information in cells and in cell networks, as well as that of genetic information, was examined to expand our understanding of how living systems are determined. Because cells are minimum units reflecting epigenetic information, which is considered to map the history of a parallel-processing recurrent network of biochemical reactions, their behaviors cannot be explained by considering only conventional DNA information-processing events. The role of epigenetic information on cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behaviour observed under conditions chosen to reveal adaptation processes, population effects and community effects. A system of analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an "algebraic" system (emphasis on temporal aspects) and as a "geometric" system (emphasis on spatial aspects). Exploiting the combination of latest microfabrication technology and measurement technologies, which we call on-chip cellomics assay, we can control and re-construct the environments and interaction of cells from "algebraic" and "geometric" viewpoints. In this review, temporal viewpoint of epigenetic information, a part of the series of single-cell-based "algebraic" and "geometric" studies of celluler systems in our research groups, are summerized and reported. The knowlege acquired from this study may lead to the use of cells that fully control practical applications like cell-based drug screening and the regeneration of organs.

    DOI PubMed

  • Extended Depth of Field Optics for Precise Image Analysis in Microfluidic Flow Cytometry

    Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FK05-1 - 06FK05-4  2012.06  [Refereed]

    　View Summary

    We have examined a method to address the defocusing problem on target samples in a microfluidic pathway by an optical approach and report our experiment. An imaging optics has been constructed for extension of the depth of focused field. This system consists of four parts: (1) a low numerical aperture (NA; i.e., large depth of field) objective lens; (2) a zoom lens; (3) a light-emitting diode (LED) illumination source; and (4) a charge-coupled device (CCD) camera. As a low NA objective lens contributes to the extension of the depth of field and a zoom lens contributes to the optimization of pixel resolution on an image sensor of a camera, the same resolution as that of a 40x objective lens was acquired by the combination of a 10x objective lens and a 4x zoom lens as the spatial resolution of the latter combination was within the size of pixels of the CCD camera. As a result, improved depth of field was obtained at any magnification from 10x to 40x, and it was indicated that an extended depth of field optics for image-based microfluidic pathways such as in flow cytometry can be constructed using a low NA objective lens and a zoom lens. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Cell-Sorting System with On-Chip Imaging for Label-Free Shape-Based Selection of Cells

    Hideyuki Terazono, Masahito Hayashi, Hyonchol Kim, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FK08-1 - 06FK08-6  2012.06

    　View Summary

    We have developed a novel cell-sorting system involving microscopic imaging using a poly(methyl methacrylate) (PMMA)-based microfluidic chip with a pair of gel electrodes and real-time image-processing procedures for the quantification of cell shapes. The features of this system are as follows. 1) It can recognize cells both by microscopic cell imaging with a 10,000 event/s high-speed camera and by the photodetection of fluorescence. 2) Multistage sorting is used to reduce errors to an infinitesimally low level by using a pair of wide agarose-gel electrodes. 3) Carry-over-free analysis can be performed using a disposable microfluidic chip. 4) An field programmable gate array (FPGA) 10,000 event/s real-time image analysis unit for quantifying the cell images in cell sorting. To separate the target cells from other cells on the basis of the cell shape, we adopted an index of roughness for the cell surface R, which compares the actual perimeter of cell surface and the estimated perimeter of cross-sectional view of cell shape by approximating the cell as a sphere. Sample cells flowing through microchannels on the chip were distinguished by the dual recognition system involving optical analysis and a fluorescence detector, and then separated. Target cells could be sorted automatically by applying an electrophoretic force, and the sorting ability depended on the precision with which cells were shifted within the laminar flow. These results indicate that the cell-sorting system with on-chip imaging is practically applicable for biological research and clinical diagnostics. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Highly Sensitive Detection of Target Biomolecules on Cell Surface Using Gold Nanoparticle Conjugated with Aptamer Probe

    Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FH01-1 - 06FH01-5  2012.06

    　View Summary

    A method of gold nanoparticle (Au NP) labeling with backscattered electron (BE) imaging of field emission scanning electron microscopy (FE-SEM) was applied for specific detection of target biomolecules on a cell surface. A single-stranded DNA aptamer, which specifically binds to the target molecule on a human acute lymphoblastic leukemia cell, was conjugated with a 20 nm Au NP and used as a probe to label its target molecule on the cell. The Au NP probe was incubated with the cell, and the interaction was confirmed using BE imaging of FE-SEM through direct counting of the number of Au NPs attached on the target cell surface. Specific Au NP-aptamer probes were observed on a single cell surface and their spatial distributions including submicron-order localizations were also clearly visualized, whereas the nonspecific aptamer probes were not observed on it. The aptamer probe can be potentially dislodged from the cell surface with treatment of nucleases, indicating that Au NP-conjugated aptamer probes can be used as sensitive and reversible probes to label target biomolecules on cells. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Importance of Thickness in Human Cardiomyocyte Network for Effective Electrophysiological Stimulation Using On-Chip Extracellular Microelectrodes

    Tomoyo Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FK03-1 - 06FK03-6  2012.06  [Refereed]

    　View Summary

    We have developed a three-dimensionally controlled in vitro human cardiomyocyte network assay for the measurements of drug-induced conductivity changes and the appearance of fatal arrhythmia such as ventricular tachycardia/ fibrillation for more precise in vitro predictive cardiotoxicity. To construct an artificial conductance propagation model of a human cardiomyocyte network, first, we examined the cell concentration dependence of the cell network heights and found the existence of a height limit of cell networks, which was double-layer height, whereas the cardiomyocytes were effectively and homogeneously cultivated within the microchamber maintaining their spatial distribution constant and their electrophysiological conductance and propagation were successfully recorded using a microelectrode array set on the bottom of the microchamber. The pacing ability of a cardiomyocyte's electrophysiological response has been evaluated using microelectrode extracellular stimulation, and the stimulation for pacing also successfully regulated the beating frequencies of two-layered cardiomyocyte networks, whereas monolayered cardiomyocyte networks were hardly stimulated by the external electrodes using the two-layered cardiomyocyte stimulation condition. The stability of the lined-up shape of human cardiomyocytes within the rectangularly arranged agarose microchambers was limited for a two-layered cardiomyocyte network because their stronger force generation shrunk those cells after peeling off the substrate. The results indicate the importance of fabrication technology of thickness control of cellular networks for effective extracellular stimulation and the potential concerning thick cardiomyocyte networks for long-term cultivation. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Quantitative Evaluation of Closed-Loop-Shaped Cardiomyocyte Network by Using Ring-Shaped Electrode

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FK06-1 - 06FK06-4  2012.06  [Refereed]

    　View Summary

    Re-entry of excitation in the heart is one of the abnormal phenomena that causes lethal arrhythmia and is thought to be induced by the looped structure of the excitation conduction pathway. To evaluate the geometrical pattern dependence of electrophysiological results, we fabricated three models of cardiomyocyte networks and compared their beating frequencies (BFs), amplitudes of a depolarization peak, and field potential durations (FPDs). The set of different closed-loop-shaped network models from 3 to 8 mm in length showed the same BFs, amplitudes, and FPDs independent of their loop lengths, whereas the BFs and FPDs of 60 mu m small clusters, and the FPDs of the 2mm open-line-shaped network model were different from those of a closed-loop-shaped network model. These results indicate that the mm order larger size of clusters might create lower BFs, and the closed-loop-shaped model may generate longer FPDs. They also suggest the importance of spatial arrangement control of the cardoimyocyte community for reproducible measurement of electrophysiological properties of cardiomyocytes, especially control of the closed-loop formation, which might change the waveforms of FPDs depending on the difference in the geometry and conduction pathway of the cell network. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Improvement of Electrical Stimulation Protocol for Simultaneous Measurement of Extracellular Potential with On-Chip Multi-Electrode Array System

    Tomoyuki Kaneko, Fumimasa Nomura, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 6 ) 06FK02-1 - 06FK02-5  2012.06  [Refereed]

    　View Summary

    Cardiotoxicity testing with a multi-electrode array (MEA) system requires the stable beating of cardiomyocytes for the measurement of the field potential duration (FPD), because different spontaneous beating rates cause different responses of FPD prolongation induced by drugs, and the beating rate change effected by drugs complicates the FPD prolongation assessment. We have developed an on-chip MEA system with electrical stimulation for the measurement of the FPD during the stable beating of human embryonic stem (ES) cell-derived cardiomyocyte clusters. Using a conventional bipolar stimulation protocol, we observed such large artifacts in electrical stimulation that we could not estimate the FPD quantitatively. Therefore, we improved the stimulation protocol by using sequential rectangular pulses in which the positive and negative stimulation voltages and number of pulses could be changed flexibly. The balanced voltages and number of pulses for sequential rectangular pulses enabled the recording of small negative artifacts only, which hardly affected the FPD measurement of human-ES-cell-derived cardiomyocyte clusters. These conditions of electrical stimulation are expected to find applications for the control of constant beating for cardiotoxicity testing. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Development of a new circulating tumor cell detection and isolation assay based on automated on-chip imaging flow cytometry technology

    Miyagi Yohei, Kim Hyonchol, Arao Tokuzo, Terazono Hideyuki, Hayashi Masato, Otsu Takashi, Nishio Kazuto, Yasuda Kenji

    CANCER RESEARCH   72  2012.04  [Refereed]

    DOI

  • 幹細胞の創薬応用を目指したオンチップ・テクノロジー

    安田 賢二, 金子 智行, 野村 典正

    ファルマシア   48 ( 9 ) 823 - 825  2012

    DOI CiNii

  • 3PS047 Fabrication of Superparamagnetic Janus Particles Having Various Sizes and Its Application for Non-Destructive Cell Sorting(The 50th Annual Meeting of the Biophysical Society of Japan)

    Kim Hyonchol, Terazono Hideyuki, Takei Hiroyuki, Yasuda Kenji

    Seibutsu Butsuri   52   S154  2012

    DOI CiNii

  • 3PS046 A Non-destructive Culturing and Cell Sorting Method for Cardiomyocytes and Neurons Using an Alginate Layer(The 50th Annual Meeting of the Biophysical Society of Japan)

    Terazono Hideyuki, Kim Hyonchol, Hattori Akihiro, Nomura Fumimasa, Kaneko Tomoyuki, Yasuda Kenji

    Seibutsu Butsuri   52   S154  2012

    DOI CiNii

  • Evaluation of a Centrifuged Double Y-Shape Microfluidic Platform for Simple Continuous Cell Environment Exchange

    Akihiro Hattori, Kenji Yasuda

    INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES   13 ( 1 ) 819 - 827  2012.01  [Refereed]

    　View Summary

    We have demonstrated the efficacy of a microfluidic medium exchange method for single cells using passive centrifugal force of a rotating microfluidic-chip based platform. At the boundary of two laminar flows at the gathering area of two microfluidic pathways in a Y-shape, the cells were successfully transported from one laminar flow to the other, without mixing the two microfluidic mediums of the two laminar flows during cell transportation, within 5 s with 1 g (150 rpm) to 36.3 g (900 rpm) acceleration, with 93.5% efficiency. The results indicate that this is one of the most simple and precise tools for exchanging medium in the shortest amount of time.

    DOI PubMed

  • On-chip constructive cell-network study (II): on-chip quasi-in vivo cardiac toxicity assay for ventricular tachycardia/fibrillation measurement using ring-shaped closed circuit microelectrode with lined-up cardiomyocyte cell network

    Fumimasa Nomura, Tomoyuki Kaneko, Akihiro Hattori, Kenji Yasuda

    JOURNAL OF NANOBIOTECHNOLOGY   9 ( 1 ) 39 - 39  2011.09  [Refereed]

    　View Summary

    Backgrounds: Conventional in vitro approach using human ether-a-go-go related gene (hERG) assay has been considered worldwide as the first screening assay for cardiac repolarization safety. However, it does not always oredict the potential QT prolongation risk or pro-arrhythmic risk correctly. For adaptable preclinical strategiesto evaluate global cardiac safety, an on-chip quasi-in vivo cardiac toxicity assay for lethal arrhythmia (ventricular tachyarrhythmia) measurement using ring-shaped closed circuit microelectrode chip has been developed.
    Results: The ventricular electrocardiogram (ECG)-like field potential data, which includes both the repolarization and the conductance abnormality, was acquired from the self-convolutied extracellular field potentials (FPs) of a lined-up cardiomyocyte network on a circle-shaped microelectrode in an agarose microchamber. When Astemisol applied to the closed-loop cardiomyocyte network, self-convoluted FP profile of normal beating changed into an early afterdepolarization (EAD) like waveform, and then showed ventricular tachyarrhythmias and ventricular fibrilations (VT/Vf). QT-prolongation-like self-convoluted FP duration prolongation and its fluctuation increase was also observed according to the increase of Astemizole concentration.
    Conclusions: The results indicate that the convoluted FPs of the quasi-in vivo cell network assay includes both of the repolarization data and the conductance abnormality of cardiomyocyte networks has the strong potential to prediction lethal arrhythmia.

    DOI PubMed

  • Orientation and Community Size Dependences of Pulsatile Electrical Field Stimulation on Lined-Up and Rod-Shaped Single Cardiomyocytes

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 8 ) 80220-1 - 80220-3  2011.08  [Refereed]

    　View Summary

    We have examined the orientation dependence of minimum electric field intensity for the stimulation of cardiomyocytes, which were cultivated in agarose chambers, using a lined-up cardiomyocyte network with different numbers of cells and orientations. When the cell network was arranged parallel to the electric field, the required minimum electric field intensity decreased to one-fourth as cell number increased, whereas that of the cell network arranged orthogonal to the electrical field did not decrease and was independent of cell number. The required electrical field intensity of the 100 mu m rod-shaped single cardiomyocyte in a microchamber arranged parallel to the electric field was also 40% lower than that of the cell network arranged orthogonal to the electric field. The results indicate that the gradient of the electric field potential between two ends of the cell network or rod-shaped single cell is important for their excitation. (C) 2011 The Japan Society of Applied Physics

    DOI

  • Quasi-In vivo Heart Electrocardiogram Measurement of ST Period Using Convolution of Cell Network Extracellular Field Potential Propagation in Lined-Up Cardiomyocyte Cell-Network Circuit

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 7 ) 70213-1 - 70213-3  2011.07  [Refereed]

    　View Summary

    A model for the quasi-in vivo heart electrocardiogram (ECG) measurement of the ST period has been developed. As the part of ECG data at the ST period is the convolution of the extracellular field potentials (FPs) of cardiomyocytes in a ventricle, we have fabricated a lined-up cardiomyocyte cell-network on a lined-up microelectrode array and a circular microelectrode in an agarose microchamber, and measured the convoluted FPs. When the ventricular tachyarrhythmias of beating occurred in the cardiomyocyte network, the convoluted FP profile showed similar arrhythmia ECG-like profiles, indicating the convoluted FPs of the in vitro cell network include both the depolarization data and the propagation manner of beating in the heart. (C) 2011 The Japan Society of Applied Physics

    DOI

  • Fully Automated On-Chip Imaging Flow Cytometry System with Disposable Contamination-Free Plastic Re-Cultivation Chip

    Masahito Hayashi, Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Tomoyuki Kaneko, Kenji Yasuda

    INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES   12 ( 6 ) 3618 - 3634  2011.06  [Refereed]

    　View Summary

    We have developed a novel imaging cytometry system using a poly(methyl methacrylate (PMMA)) based microfluidic chip. The system was contamination-free, because sample suspensions contacted only with a flammable PMMA chip and no other component of the system. The transparency and low-fluorescence of PMMA was suitable for microscopic imaging of cells flowing through microchannels on the chip. Sample particles flowing through microchannels on the chip were discriminated by an image-recognition unit with a high-speed camera in real time at the rate of 200 event/s, e. g., microparticles 2.5 mu m and 3.0 mu m in diameter were differentiated with an error rate of less than 2%. Desired cells were separated automatically from other cells by electrophoretic or dielectrophoretic force one by one with a separation efficiency of 90%. Cells in suspension with fluorescent dye were separated using the same kind of microfluidic chip. Sample of 5 mu L with 1 x 10(6) particle/mL was processed within 40 min. Separated cells could be cultured on the microfluidic chip without contamination. The whole operation of sample handling was automated using 3D micropipetting system. These results showed that the novel imaging flow cytometry system is practically applicable for biological research and clinical diagnostics.

    DOI PubMed

  • Image-Based Identification of Single Neurons for Noninvasive Imaging Purification

    Hideyuki Terazono, Masahito Hayashi, Hyonchol Kim, Akihiro Hattori, Tomoyuki Kaneko, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 6 ) 06GL07-1 - 06GL07-4  2011.06  [Refereed]

    　View Summary

    A single-cell-based screening assay requires strict identification and isolation of particular target cells from a mixture of various kinds of cells. We have developed a visual-image-based on-chip microfluidic cell sorting method for the collection of neurons. One of the advantages of our method of purifying neurons is the direct monitoring and reorganization of neurons with specific image indexes, such as the cell size, shape, internal complexity, and spatial distribution of a fluorescent dye of a specific antibody marker by phase-contrast/fluorescence microscopy and image processing, which has not been realized using conventional diffraction-based cell sorting systems. First, we compared the differences of microscopic images (shapes) of neurons and glia cells, and found that only neurons have neurites extending from the cell body. We also found that the smooth surface shape indicates neurons, and the rough surface shape indicates glia cells. After picking the neuron cells manually chosen by observing their shapes as described above, we confirmed that the purified neurons can be cultivated and can keep their electrophysiological functions on the chip even after the purification procedure. The results indicate the potential of a nonlabel, noninvasive on-chip cell sorting procedure for neurons using micrograph images for an on-chip ultrahigh-speed camera-based imaging cell sorter. (c) 2011 The Japan Society of Applied Physics

    DOI

  • Improvement of Particle Alignment Control and Precise Image Acquisition for On-Chip High-Speed Imaging Cell Sorter

    Akihiro Hattori, Tomoyuki Kaneko, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 6 ) 06GL06-1 - 06GL06-8  2011.06  [Refereed]

    　View Summary

    We have developed a real-time imaging cell sorting system composed of a micrometer-sized gel-electrode-embedded microfluidic sorting chip and a real-time image analysis/recognition unit equipped with a high-speed camera and image processing circuits. For the microfluidic continuous cell sorting, we have examined the precise position and velocity control of flowing particles and the precise acquisition of microscopic images of flowing particles. The results showed that (1) hydrodynamic focusing can line up particles precisely within a range of 5 mu m particle size distribution, (2) active air pressure-driven flow velocity control can create the flow in the microfluidic pathways up to 160 mm/s with 0.15 MPa air pressure maintaining linear correlation between air pressure and flow velocity, and (3) 1 mu s flash illumination can prevent the blur even under 200 mm/s flow. Applying the above elements into the system, the recognition error of target particles was within 5% for 2 mu m particles with 2.5 mm/s flow. The experimental results demonstrate the potential of the image index-based on-chip cell sorter for practical application. (c) 2011 The Japan Society of Applied Physics

    DOI

  • Continuous Concentration and Separation of Microparticles Using Dielectrophoretic Force in a V-Shaped Electrode Array

    Masahito Hayashi, Tomoyuki Kaneko, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 6 ) 06GL03-1 - 06GL03-5  2011.06  [Refereed]

    　View Summary

    We have proposed and developed the novel principle of a V-shaped electrode array in a microfluidic pathway for continuous concentration and separation of particles by dielectrophoretic (DEP) force. The advantage of V-shape microelectrode arrays with a microfluidic flow for cell separation is that whole particles are concentrated into the center of a micropathway independent of the difference in their dielectric constants in the X-Y plane, while the particles are split between the top or bottom of the micropathway in the Z-axis direction depending on the differences in their dielectric constants and the applied AC frequency. After the application of a sinusoidal AC voltage of 1MHz and 20 V-pp, both polystyrene spheres and Bacillus subtilis spores were concentrated at the tip of the V-shaped electrode at the center of microfluidic flow in the X-Y plane independent of their dielectric constant differences. They were also split into two directions in the Z-axis, i.e., polystyrene spheres rose to the top, and spores went down to the bottom depending on their dielectric constant differences and were successfully separated in two layered downstreams. The results indicate the potential of V-shaped electrode arrays for simple continuous purification of mixed particles depending on their dielectric constants. (c) 2011 The Japan Society of Applied Physics

    DOI

  • Production of Double-Layered Metal Nanocups for Artificial Nanospace of Biomolecular Reaction

    Hyonchol Kim, Masahito Hayashi, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 ( 6 ) 06GJ03-1 - 06GJ03-4  2011.06  [Refereed]

    　View Summary

    Nanocups (NCs), sub-micrometer semispherical bowls consisting of two different nanometer-thick metals on inner and outer layers, have been fabricated to mimic a localized nano-scale biochemical reaction environment for reactive biomolecules. Homogeneous polystyrene beads were used as a cast of the NCs, placed on a Si substrate, dried, and processed by oxygen plasma etching until the desired diameters and gaps among neighboring bead casts. For the fabrication of Au/Ni double-layered NCs, Au and Ni were sequentially deposited on upper halves of the bead surfaces by thermal evaporation with nanometer-order thickness control. The polystyrene casts were removed completely by UV-ozone oxidization reaction, and Au/Ni double-layered NCs were fabricated on a Si substrate. To orient the holes of the fabricated NCs to top for the substrate, poly(dimethylsiloxane) (PDMS) sol was dropped on the NCs placed on the Si substrate, hardened, and peeled off from the substrate, and then the NCs were placed on the PDMS surface with those holes turned-up. To examine the selective interaction of biomolecules on the inner layer of NCs as the artificial nanospace for biomolecular reactions, a thiolated target DNA was immobilized onto the inner layer of a Au/Ni NC as a model. The target DNA was labeled through hybridization reaction using small Au nanoparticles (NPs) on which a complementary probe DNA was immobilized. Both the surface-specific immobilization of the target DNA on the Au layer of the NC and the specific hybridization in NC nanospaces were confirmed by direct observations after those reactions using field emission scanning electron microscopy (FE-SEM), indicating that the inside of the fabricated NCs can be used as the artificial nanospace for studying localized biomolecular reactions. (C) 2011 The Japan Society of Applied Physics

    DOI

  • On-chip constructive cell-Network study (I): Contribution of cardiac fibroblasts to cardiomyocyte beating synchronization and community effect

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    JOURNAL OF NANOBIOTECHNOLOGY   9 ( 21 ) 1 - 13  2011.05  [Refereed]

    　View Summary

    Backgrounds: To clarify the role of cardiac fibroblasts in beating synchronization, we have made simple lined-up cardiomyocyte-fibroblast network model in an on-chip single-cell-based cultivation system.
    Results: The synchronization phenomenon of two cardiomyocyte networks connected by fibroblasts showed (1) propagation velocity of electrophysiological signals decreased a magnitude depending on the increasing number of fibroblasts, not the lengths of fibroblasts; (2) fluctuation of interbeat intervals of the synchronized two cardiomyocyte network connected by fibroblasts did not always decreased, and was opposite from homogeneous cardiomyocyte networks; and (3) the synchronized cardiomyocytes connected by fibroblasts sometimes loses their synchronized condition and recovered to synchronized condition, in which the length of asynchronized period was shorter less than 30 beats and was independent to their cultivation time, whereas the length of synchronized period increased according to cultivation time.
    Conclusions: The results indicated that fibroblasts can connect cardiomyocytes electrically but do not significantly enhance and contribute to beating interval stability and synchronization. This might also mean that an increase in the number of fibroblasts in heart tissue reduces the cardiomyocyte 'community effect', which enhances synchronization and stability of their beating rhythms.

    DOI PubMed

  • Backscattered Electron Contrast Imaging of Scanning Electron Microscopy for Identifying Double Layered Nano-Scale Elements

    Hyonchol Kim, Tsutomu Negishi, Masato Kudo, Hiroyuki Takei, Kenji Yasuda

    Journal of Surface Analysis   17 ( 3 ) 341 - 345  2011.03

    DOI

  • ヒトｉＰＳなどの幹細胞から分化した心筋細胞を用いた不整脈予測法の開発

    安田 賢二, 金子 智行, 野村 典正

    心電図   31 ( 3 ) 318 - 324  2011

    　View Summary

    現在，薬物の心毒性を検証するための主要な計測手法は，常に偽陰性（false negative）の危険性を内在している．ヒト幹細胞からヒト心筋細胞の再生が可能になったため，再生された心筋細胞をチップ上に1細胞単位で構成的に配置して，ヒト臓器・組織の応答により近いin vitro細胞ネットワークモデルを構築することが可能になった．そのモデルを使用し，(1)細胞のK+イオンチャネルの応答のゆらぎ解析による安定性変化の定量化（時間的観点），(2)心筋細胞ネットワークにおける伝導状態のゆらぎ解析による伝導異常の定量化（空間的観点）のふたつの観点から，心筋細胞間の興奮伝導の異常発生を定量的に観測できる心毒性検査法を検討した．その結果， in vitro系であっても偽陰性の薬剤を「ゆらぎ」から効果的に識別できることを確認した．細胞間の興奮収縮の伝導異常である致死性不整脈の発生を計測するには，従来の細胞計測に加えて，細胞間の相互作用を理解するための細胞ネットワークの階層という，新しいin vitroプラットホームが重要であると考えられる．

    DOI CiNii

  • CONSTRUCTION AND ANALYSIS OF AN ARTIFICIAL NEURONAL NETWORK USING A NEURON-COLLECTING, MICRO-PATTERNING METHOD BASED ON A MULTI-ELECTRODE ARRAY SYSTEM

    Hideyuki Terazono, Hyonchol Kim, Masahito Hayashi, Akihiro Hattori, Hiroyuki Takei, Kenji Yasuda

    NCTA 2011: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON NEURAL COMPUTATION THEORY AND APPLICATIONS     304 - 307  2011  [Refereed]

    　View Summary

    We developed three techniques to make artificial neuronal networks constructed from rat hippocampal neurons. 1) a method of non-invasively collecting primary cultured neurons and their deposition, 2) a technique for microprocessing agarose for the purpose of assembling artificial neuronal networks, 3) a multi-electrode array system for measurement of the multi-point extracellular potential of neurons. The three techniques allow us to assemble and evaluate artificial neuronal networks constructed from particular cells. We can manipulate neuro-transmission pathways and investigate roles played by the innate period or stability information for each individual cell in the framework of physiological mechanism. It is thus possible to construct and demonstrated the actual neuronal networks simulated by the computed neural networks.

  • Construction of an artificial neuronal network and electrophysiological measurement with a selective collection method of cultured primary neurons

    Terazono Hideyuki, Kim Hyonchol, Hayashi Masahito, Hattori Akihiro, Yasuda Kenji

    Neuroscience Research   71   E414  2011  [Refereed]

    DOI

  • On-Chip Cellomics for Cardiotoxity: Cell Network Model For Re-Construction of Higher Complexity of Organs

    Yasuda K

    The Open Conference Proceedings Journal   1   168 - 177  2010.10

    DOI

  • Quantitative backscattered electron imaging of field emission scanning electron microscopy for discrimination of nano-scale elements with nm-order spatial resolution

    Hyonchol Kim, Tsutomu Negishi, Masato Kudo, Hiroyuki Takei, Kenji Yasuda

    JOURNAL OF ELECTRON MICROSCOPY   59 ( 5 ) 379 - 385  2010.10

    　View Summary

    Discrimination of thin film elements by backscattered electron (BSE) imaging of field emission scanning electron microscope was examined. Incident electron acceleration voltage dependence on thin films' BSE intensities in five elements (Au, Ag, Ge, Cu and Fe) on a silicon substrate was experimentally measured from 3 to 30 kV. Normalization of BSE intensities using the difference between maximum and minimum brightness was proposed and allowed reproducible comparison among the elements. Measured intensities, which have correlation with electron backscattering coefficient against atomic number, indicated the existence of adequate acceleration voltage for improvement of resolution to discriminate different elements, showing the possibility of discriminating at least these six elements simultaneously by BSE imaging with nanometer-scale spatial resolution.

    DOI

  • Using single cell cultivation system for on-chip monitoring of the interdivision timer in Chlamydomonas reinhardtii cell cycle

    Kazunori Matsumura, Toshiki Yagi, Akihiro Hattori, Mikhail Soloviev, Kenji Yasuda

    Journal of Nanobiotechnology   8 ( 23 ) 1 - 13  2010.09

    　View Summary

    Regulation of cell cycle progression in changing environments is vital for cell survival and maintenance, and different regulation mechanisms based on cell size and cell cycle time have been proposed. To determine the mechanism of cell cycle regulation in the unicellular green algae Chlamydomonas reinhardtii, we developed an on-chip single-cell cultivation system that allows for the strict control of the extracellular environment. We divided the Chlamydomonas cell cycle into interdivision and division phases on the basis of changes in cell size and found that, regardless of the amount of photosynthetically active radiation (PAR) and the extent of illumination, the length of the interdivision phase was inversely proportional to the rate of increase of cell volume. Their product remains constant indicating the existence of an 'interdivision timer'. The length of the division phase, in contrast, remained nearly constant. Cells cultivated under light-dark-light conditions did not divide unless they had grown to twice their initial volume during the first light period. This indicates the existence of a 'commitment sizer'. The ratio of the cell volume at the beginning of the division phase to the initial cell volume determined the number of daughter cells, indicating the existence of a 'mitotic sizer'.© 2010 Matsumura et al
    licensee BioMed Central Ltd.

    DOI

  • Production of Nanoparticles Using Several Materials for Labeling of Biological Molecules

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 8 ) 87001-1 - 87001-7  2010.08

    　View Summary

    Various size-controlled metal nanoparticles (NPs) coated with probe DNAs have been developed Gold, silver, germanium, copper, or nickel was thermally deposited as the inner layer on the surface of a polystyrene bead, and gold was coated as the outer layer for immobilizing thiolated probe DNAs by Au-S covalent bonding The ultraviolet visible (UV-vis) spectra of NPs showed that an outer gold layer thickness of 2 nm was sufficient for the immobilization of probe DNAs having a signal/noise (S/N) ratio of specific attachment of NP probes on the DNA chips eight-times higher than that of fluorescent probes The size distributions of NPs were within the 6 7% coefficient of variation regardless of the type of metal and size The different metal layers of NPs were also discriminated successfully by measuring backscattered electron intensity by scanning electron microscopy (SEM) The results indicate that NPs can be used for a two-dimensional probe set for SEM observation of size differences and differences in the type of metal used (C) 2010 The Japan Society of Applied Physics

    DOI

  • Labelling of live cells using fluorescent aptamers: Binding reversal with DNA nucleases

    Hideyuki Terazono, Yu Anzai, Mikhail Soloviev, Kenji Yasuda

    Journal of Nanobiotechnology   8 ( 8 ) 1 - 5  2010.04

    　View Summary

    A reversible cell labelling method has been developed for non-destructive and non-invasive cell labelling and purification. Our method uses high affinity single strand DNA (ssDNA) aptamers against surface exposed target molecules on cells. The aptamers are subsequently removed from the cell surface using DNase nuclease treatment. We exemplified our method by labelling human acute lymphoblastic leukemia cells with Qdot-ssDNA aptamers, and restoring them to the label-free condition by treatment with Benzonase. Binding of the fluorescent-aptamers to the cells was evaluated by measuring fluorescence intensity and was further confirmed using flow cytometry. Removal of the aptamers can be achieved in ~10 min by the DNase nuclease digestion. Incubation of cells with aptamers or with the nucleases results in no apparent damage to the cells and does not affect their growth rates. The latter were equivalent to the rates measured for the untreated cells. Our method provides an alternative to traditional antibody-based techniques and could be especially suitable for non-invasive reversible cell labelling and cell separations where maintaining native cell activity is needed. © 2010 Terazono et al
    licensee BioMed Central Ltd.

    DOI

  • Algebraic and Geometric Understanding of Cells: Epigenetic Inheritance of Phenotypes Between Generations

    Kenji Yasuda

    High Resolution Microbial Single Cell Analytics   124   55 - 81  2010

    　View Summary

    We have developed methods and systems for analyzing epigenetic information in cells, as well as that of genetic information, to expand our understanding of how living systems are determined. Because cells are minimum units reflecting epigenetic information, which is considered to map the history of a parallel-processing recurrent network of biochemical reactions, their behaviors cannot be explained by considering only conventional DNA informationprocessing events. The role of epigenetic information in cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behavior observed under conditions chosen to reveal adaptation processes and community effects. A system for analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an 'algebraic' system (emphasis on temporal aspects) and as a 'geometric' system (emphasis on spatial aspects). The knowledge acquired from this study may lead to the use of cells that fully control practical applications like cell-based drug screening and the regeneration of organs. © Springer-Verlag Berlin Heidelberg 2010.

    DOI PubMed

  • Quantitative evaluation of a gold-nanoparticle labeling method for detecting target DNAs on DNA microarrays

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    SENSORS AND ACTUATORS B-CHEMICAL   144 ( 1 ) 6 - 10  2010.01

    　View Summary

    The detection sensitivity obtained when combining electron-microscopy counting with gold-nanoparticle labeling of target nucleic acids complementary to probe DNA microarrays with the detection sensitivity obtained when using optical-microscopy measurement of conventional fluorescent labeling. Target DNAs were reacted with probe DNAs on DNA microarrays on which micro-columns had been etched so the target DNA could be agitated. The targets were reacted with the other probe DNA immobilized onto the Surface of the nanoparticles. The labeled target DNAs were measured by using field-emission scanning electron microscopy (FE-SEM) imaging and counting the nanoparticles. The detection sensitivity of nanoparticle-labeling measurement was 1000 times that of fluorescent-labeling measurement, and the S/N ratio of nanoparticle-labeling measurement was 100 times that Of fluorescent-labeling measurement. The results indicate that the nanoparticle-labeling method using FE-SEM counting is sensitive enough that it has a possibility for measuring targets expressed in a cell without amplification such as polymerase chain reaction (PCR). (C) 2009 Elsevier B.V. All rights reserved.

    DOI

  • Development of a high-speed real-time PCR system for rapid and precise nucleotide recognition

    Hideyuki Terazono, Hiroyuki Takei, Akihiro Hattori, Kenji Yasuda

    ADVANCED ENVIRONMENTAL, CHEMICAL, AND BIOLOGICAL SENSING TECHNOLOGIES VII   7673   76730U  2010  [Refereed]

    　View Summary

    Polymerase chain reaction (PCR) is a common method used to create copies of a specific target region of a DNA sequence and to produce large quantities of DNA. A few DNA molecules, which act as templates, are rapidly amplified by PCR into many billions of copies. PCR is a key technology in genome-based biological analysis, revolutionizing many life science fields such as medical diagnostics, food safety monitoring, and countermeasures against bioterrorism. Thus, many applications have been developed with the thermal cycling. For these PCR applications, one of the most important key factors is reduction in the data acquisition time. To reduce the acquisition time, it is necessary to decrease the temperature transition time between the high and low ends as much as possible. We have developed a novel rapid real-time PCR system based on rapid exchange of media maintained at different temperatures. This system consists of two thermal reservoirs and a reaction chamber for PCR observation. The temperature transition was achieved within 0.3 sec, and good thermal stability was achieved during thermal cycling with rapid exchange of circulating media. This system allows rigorous optimization of the temperatures required for each stage of the PCR processes. Resulting amplicons were confirmed by electrophoresis. Using the system, rapid DNA amplification was accomplished within 3.5 min, including initial heating and complete 50 PCR cycles. It clearly shows that the device could allow us faster temperature switching than the conventional conduction-based heating systems based on Peltier heating/cooling.

    DOI

  • Production of Size-Controlled Nanoscopic Cap-Shaped Metal Shells

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 4 ) 48004-1 - 48004-2  2010

    　View Summary

    A method of producing precisely size-controlled metal nanoparticles is described. Polystyrene (PS) spheres placed on a substrate were used as a cast for the metal nanoparticles. The diameters of the PS spheres were processed into the desired sizes by oxygen plasma etching, and metal was deposited on the PS to the desired thickness by thermal evaporation. The PS casts were then removed by the UV-excited ozone oxidization reaction. The diameters of the obtained cap-shaped metal shells had a distribution within 5% of the coefficient of variation. These particles can be used as simultaneously applicable biological labels along with different-sized nanoparticles in immuno-electron microscopy. (C) 2010 The Japan Society of Applied Physics DOI: 10.1143/JJAP.49.048004

    DOI

  • Development of an integrated system for rapid detection of biological agents

    Hideyuki Terazono, Hiroyuki Takei, Masahito Hayashi, Akihiro Hattori, Kenji Yasuda

    CHEMICAL, BIOLOGICAL, RADIOLOGICAL, NUCLEAR, AND EXPLOSIVES (CBRNE) SENSING XI   7665   766503  2010  [Refereed]

    　View Summary

    Weaponized biological agents are as great a threat as nuclear or chemical weapons. They must be detected at the earliest stage to prevent diffusion because once these agents are dispersed into the air, the rapidly decreasing concentration makes detection more of a challenge. Polymerase chain reaction (PCR) is a common method to create copies of a specific target region of a DNA sequence and to produce large quantities of DNA molecules. A few DNA molecules are rapidly amplified by PCR into billions of copies. While PCR is a powerful technique and is capable of countering new threats relatively easily, it is plagued by the number of processes necessary. Therefore, we have developed an integrated PCR system for rapid detection of biological agents captured from the air. Each processing function is performed by a dedicated module, and reduction in the process time has been made the top priority, without loss in the signal/noise ratio of the total system. Agents can be identified within 15 min from capture. A fully automated operation protects operators from exposure to potentially highly lethal samples.

    DOI

  • Comprehensive Study of Microgel Electrode for On-Chip Electrophoretic Cell Sorting

    Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 6 ) 06GM04-1 - 06GM04-4  2010  [Refereed]

    　View Summary

    We have developed an on-chip cell sorting system and microgel electrode for applying electrostatic force in microfluidic pathways in the chip. The advantages of agarose electrodes are 1) current-driven electrostatic force generation, 2) stability against pH change and chemicals, and 3) no bubble formation caused by electrolysis. We examined the carrier ion type and concentration dependence of microgel electrode impedance, and found that CoCl2 has less than 1/10 of the impedance from NaCl, and the reduction of the impedance of NaCl gel electrode was plateaued at 0.5 M. The structure control of the microgel electrode exploiting the surface tension of sol-state agarose was also introduced. The addition of 1% (w/v) trehalose into the microgel electrode allowed the frozen storage of the microgel electrode chip. The experimental results demonstrate the potential of our system and microgel electrode for practical applications in microfluidic chips. (C) 2010 The Japan Society of Applied Physics

    DOI

  • Development of a High-Speed Real-Time Polymerase Chain Reaction System Using a Circulating Water-Based Rapid Heat-Exchange

    Hideyuki Terazono, Hiroyuki Takei, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 6 ) 06GM05-1 - 06GM05-5  2010  [Refereed]

    　View Summary

    Polymerase chain reaction (PCR) is a powerful technique to detect microorganisms, viruses, or cells by amplifying a single copy or a few copies of a fragment of a particular DNA sequence. To reduce acquisition time, it is necessary to decrease the temperature transition time between denaturation and extension. We have developed a simple rapid real-time microlitter-sample droplet PCR system accomplished by the rapid liquidbased heat-exchange of sample droplets by quick switching of two circulating hot waters of denaturation and extension, a microlitter-sized droplet and a thin-film aluminum chip. Using this system, rapid PCR amplification of a set of droplets lined up on an aluminum chip was conducted successfully as shown by the increase in fluorescence intensity, and was accomplished within 3.5 min in 40 cycles of 1 s denaturation and 3 s extension reaction, which is one magnitude faster than conventional fast PCR systems. This method allows the rapid detection of DNA fragments and has a possibility for measuring multiple samples simultaneously in a miniaturized microfluidic chip. (C) 2010 The Japan Society of Applied Physics

    DOI

  • Non-amplified Quantitative Detection of Nucleic Acid Sequences Using a Gold Nanoparticle Probe Set and Field-Emission Scanning Electron Microscopy

    Hyonchol Kim, Atsushi Kira, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 6 ) 06GK07-1 - 06GK07-6  2010

    　View Summary

    For the precise detection of the number of expressed biomarkers at the single-cell level, we have developed a method of quantifying and specifying target DNA fragments by using a set of gold nanoparticles as labels and field-emission scanning electron microscopy (FE-SEM) to measure the number and sizes of gold nanoparticles attached to target samples. One or more target DNAs on a substrate were labeled with a set of different-sized gold nanoparticle probes having complementary sequences to different target candidates. The type and number of the target DNAs having a specific sequence were identified by counting the attached nanoparticles of a specific size in FE-SEM images. The results evaluated using a DNA microarray showed high specificity and sensitivity, and a linear correlation between the number of attached particles and the target DNA concentration, indicating the feasibility of quantitative detection in the femtomolar to nanomolar concentration range. (C) 2010 The Japan Society of Applied Physics

    DOI

  • Simple Microfluidic Continuous Concentration of Microparticles with Different Dielectric Constants Using Dielectrophoretic Force in a V-Shaped Electrode Array

    Masahito Hayashi, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   49 ( 9 ) 97002-1 - 97002-5  2010  [Refereed]

    　View Summary

    We show here that the viscous drag and dielectrophoretic force generated in a V-shaped ladder electrode array in a microfluidic channel cause both attracted and repelled microparticles to move to the electrodes at the centre of the channel. Both Bacillus spores and 1-mu m polystyrene spheres in a flow concentrated at the edges of V-shaped electrodes to which a 20 V(pp) 1MHz AC voltage was applied. The results indicated the advantages of this simple setup for concentrating microparticles regardless of their dielectric constants, which is essential for highly precise cell separation and analysis. (C) 2010 The Japan Society of Applied Physics

    DOI

  • On-chip pre-clinical cardiac toxicity: Testing compounds beyond hERG and QT using hES/hiPS cardiomyocyte cell network re-entry model on a chip

    Kenji Yasuda, Tomoyuki Kaneko, Fumimasa Nomura, Atsushi Sugiyama

    JOURNAL OF PHARMACOLOGICAL SCIENCES   112   13P - 13P  2010  [Refereed]

    　View Summary

    Limitation of conventional hERG assay and QT prolongation testing for accurate prediction of Torsades de Pointes (TdP) by compounds unvailed us the necesity of new approach to evaluate global cardiac safety. On-chip re-entry cell network model assay has the potential to measure the TdP probability as pre-clinical testing for cardiac safety by the single cell-based optical/electrical measurement of the heart pressure, Na, K, Ca ion channel conditions and their fluctuations. The application of ion channel inhibitors resulted in dose-dependent changes to the field potential waveform, and these changes were identical to those induced in the native cardiomyocytes. This study shows that on-chip model represent a promising in vitro assay for cardiac toxicity and drug screening.

  • Production of nanoscopic metal labels for electron microscopy: Specific detection of target DNA

    Hyonchol Kim, Kenji Yasuda, Hiroyuki Takei

    SENSORS AND ACTUATORS B-CHEMICAL   142 ( 1 ) 1 - 6  2009.10

    　View Summary

    The simultaneous detection of multiple target biomolecules with scanning electron microscopy is difficult due to the lack of a suitable label set. Unlike the fluorescence dyes used for fluorescence microscopy, there are no readily available labels that can be distinguished. We propose using nanoscopic metal particles of different element species as labels because various metals scatter electrons differently, making them distinguishable in backscattered electron images. We have developed a universal method for forming such metal particles. They are prepared by thermal deposition of a metal onto surface-adsorbed latex spheres having the shape of a half-shell, creating exposed metal and latex surfaces. Either surface can be selectively modified with probe DNA to enable the half-shell label to react with target DNA. Half-shells prepared with different metals were clearly distinguished in the backscattered electron observation mode of a field emission scanning electron microscope. Target DNA was detected with these half-shells, indicating that this half-shell labeling can be used for simultaneous detection of specific target biomolecules. (c) 2009 Elsevier B.V. All rights reserved.

    DOI

  • In vitro pharmacologic testing using human induced pluripotent stem cell-derived cardiomyocytes

    Tomofumi Tanaka, Shugo Tohyama, Mitsushige Murata, Fumimasa Nomura, Tomoyuki Kaneko, Hao Chen, Fumiyuki Hattori, Toru Egashira, Tomohisa Seki, Yohei Ohno, Uichi Koshimizu, Shinsuke Yuasa, Satoshi Ogawa, Shinya Yamanaka, Kenji Yasuda, Keiichi Fukuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   385 ( 4 ) 497 - 502  2009.08  [Refereed]

    　View Summary

    The lethal ventricular arrhythmia Torsade de pointes (TdP) is the most common reason for the withdrawal or restricted use of many cardiovascular and non-cardiovascular drugs. The lack of an in vitro model to detect pro-arrhythmic effects on human heart cells hinders the development of new drugs. We hypothesized that recently established human induced pluripotent stem (hiPS) cells could be used in an in vitro drug screening model. In this study, hiPS cells were driven to differentiate into functional cardiomyocytes, which expressed cardiac markers including Nkx2.5, GATA4, and atrial natriuretic peptide. The hiPS-derived cardiomyocytes (hiPS-CMs) were analyzed using a multi electrode assay. The application of ion channel inhibitors resulted in dose-dependent changes to the field potential waveform, and these changes were identical to those induced in the native cardiomyocytes. This study shows that hiPS-CMs represent a promising in vitro model for cardiac electrophysiologic studies and drug screening. (c) 2009 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Inter-sarcomere coordination in muscle revealed through individual sarcomere response to quick stretch

    Yuta Shimamoto, Madoka Suzuki, Sergey V. Mikhailenko, Kenji Yasuda, Shin&apos;ichi Ishiwata

    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA   106 ( 29 ) 11954 - 11959  2009.07  [Refereed]

    　View Summary

    The force generation and motion of muscle are produced by the collective work of thousands of sarcomeres, the basic structural units of striated muscle. Based on their series connection to form a myofibril, it is expected that sarcomeres are mechanically and/or structurally coupled to each other. However, the behavior of individual sarcomeres and the coupling dynamics between sarcomeres remain elusive, because muscle mechanics has so far been investigated mainly by analyzing the averaged behavior of thousands of sarcomeres in muscle fibers. In this study, we directly measured the length-responses of individual sarcomeres to quick stretch at partial activation, using micromanipulation of skeletal myofibrils under a phase-contrast microscope. The experiments were performed at ADP-activation (1 mM MgATP and 2 mM MgADP in the absence of Ca(2+)) and also at Ca(2+)-activation (1 mM MgATP at pCa 6.3) conditions. We show that under these activation conditions, sarcomeres exhibit 2 distinct types of responses, either "resisting" or "yielding," which are clearly distinguished by the lengthening distance of single sarcomeres in response to stretch. These 2 types of sarcomeres tended to coexist within the myofibril, and the sarcomere "yielding" occurred in clusters composed of several adjacent sarcomeres. The labeling of Z-line with anti-alpha-actinin antibody significantly suppressed the clustered sarcomere "yielding." These results strongly suggest that the contractile system of muscle possesses the mechanism of structure-based inter-sarcomere coordination.

    DOI PubMed

  • Homogeneous immobilization of probe DNAs on DNA chip using polyurea thin film

    Atsushi Kira, Hyonchol Kim, Kenji Yasuda

    e-Journal of Surface Science and Nanotechnology   7   728 - 730  2009.06

    　View Summary

    We propose a method to attach probe DNAs with a homogeneous population for quantitative measurement of a minimum number of target DNA/RNA for the next generation of DNA chip. To control the homogeneous population of DNA probes, polymer films having neighboring reactive groups at the same distance, i.e., aromatic polyurea film formed with 3,5-diaminobenzonic acid (DBA) and methylenedi(p-phenylene) diisocyanate (MDI) and aliphatic polyurea film formed with DBA and hexamethylene diisocyanate (HDI), were polymerized directly on the surface of a chip substrate by vapor deposition polymerization. The spatial arrangement and homogeneity of the reactive groups on the surfaces of the substrates were examined by observing the immobilization of DNA fragments bound to 20-nm gold nano-particles on the polymer films. The results showed that physical adsorption of the DNA was effectively inhibited on the DBA/HDI film in contrast to the DBA/MDI film and the conventional aminosilane surface. Moreover, the distribution of the particles was homogeneous on the DBA/HDI film, unlike on the other surfaces. These results indicate that the aliphatic polyurea film could be used to control the selectivity and uniformity of reactive groups on the surface of substrates for more precise quantitative measurement of DNA chip technology. © 2009 The Surface Science Society of Japan.

    DOI

  • Contribution of Nanoscale Curvature to Number Density of Immobilized DNA on Gold Nanoparticles

    Atsushi Kira, Hyonchol Kim, Kenji Yasuda

    LANGMUIR   25 ( 3 ) 1285 - 1288  2009.02

    　View Summary

    We report the curvature size dependence of the density of attached single-stranded DNA (ssDNA) on the surface of gold nanoparticles. The densities of immobilized ssDNA on 10, 20,30, and 50 nm gold nanoparticles were examined, and we found that the maximum density of the immobilized ssDNA on 10 nm particles was 13 times larger than that on 50 nm particles, which was still 10 Limes larger than that on flat gold surfaces. This result indicates the importance of curvature in the nanometer-scale attachment of ssDNAs to nanoparticles.

    DOI PubMed

  • 最近の話題 オンチップ・セロミクス計測システム

    寺薗 英之, 安田 賢二

    日本薬理学雑誌   132 ( 3 ) 192 - 193  2008.09

  • Development of 1480 nm photothermal high-speed real-time polymerase chain reaction system for rapid nucleotide recognition

    Hideyuki Terazono, Akihiro Hattori, Hiroyuki Takei, Kazuo Takeda, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   47 ( 6 ) 5212 - 5216  2008.06  [Refereed]

    　View Summary

    The polymerase chain reaction (PCR) is a key technology used in genome-based biological analysis; however, requests have been made to shorten the operation time for emergency tests such as medical diagnostics, and countermeasures against bioterrorism. We have developed a novel rapid real-time PCR system using the direct absorption of an IR laser beam by water droplets as the heating device. The advantage of this system is that only the target water droplet was heated photothermally without transmitting any heat to the surroundings, which is important for the production of fast thermal cycle intervals. The system consists of a fluorescent microscope, an oil chamber with a set of water droplets lined up at the bottom, a 1480 nm IR laser unit, which is absorbed by water and can be focused on the droplets on the stage of the microscope, and an image intensifier to quantify the PCR reaction within a water droplet by measuring the change of fluorescent intensity. Using the system, we examined the PCR procedure under the following conditions: initial heating to 95 degrees C, maintaining this temperature for 10 s, and the suggested here and in similar places throughout 50 cycles of I s at 95 degrees C for denaturation and 3 s at 60 degrees C for annealing/extension. The temperature increase and decrease between the two temperatures 95 and 60 degrees C, were within 1 and 0.8 s respectively, i.e., 32 K/s, which is 1.5 times faster than the conventional heat conduction-based system. Rapid PCR amplification was observed successfully by the rise change in the sigmoidal curvature of fluorescent intensity, and the procedure was accomplished within 3.5 min, including the initial heating and complete 50 PCR cycles. The results indicate that the direct absorption-based heating of water droplets photothermally could give us a faster temperature chnage than the conventional heat-conduction-based systems such as Peltier heating/cooling.

    DOI

  • Collagen micro-flow channels as an for in vitro blood-brain barrier model

    Katsuya Shibata, Hideyuki Terazono, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS   47 ( 6 ) 5208 - 5211  2008.06  [Refereed]

    　View Summary

    An in vitro blood-brain barrier (BBB) model is useful for drug discovery and efficacy measurements because it is a simple and convenient model of the in vivo BBB. However, the conventional in vitro BBB model does not account for shear stress to endotherial cell (EC) layers although in vivo ECs are exposed by shear stress. To improve this deficiency, we applied a microfluidics technique to a conventional in vitro BBB model and constructed a new in vitro BBB model. First, we confirmed that ECs can survive and proliferate on a cross-linked collagen gel and on an agarose including microbeads decorated with collagen type IV (CIV). In addition, we found that the cross-linker 1-ethyl-3carbodiimide hydrochloride (EDC) with N-hydroxysuccinimide (NHS) is less effective for EC proliferation than glutaraldehyde (GA), ethyleneglycol diglycidyl ether (EGDE), and agarose with microbeads. Applying a focused infrared laser, we fabricated microtunnels within the collagen gel, and we successfully cultured ECs on the inner tunnel wall. The results indicate the potential of gel microstructures for a microfluidic in vitro BBB model.

    DOI

  • オンチップ・セルソーター・システム

    寺薗 英之, 林 真人, 川瀬 芳恵, 安西 悠, 服部 明弘, 安田 賢二

    生体材料工学研究所年報   41   34 - 37  2008.03

  • Single-cell observation of phagocytosis by human blood dendritic cells

    Hiroshi Ishimoto, Katsunori Yanagihara, Nobuko Araki, Hiroshi Mukae, Noriho Sakamoto, Koichi Izumikawa, Masafumi Seki, Yoshitsugu Miyazaki, Yoichi Hirakata, Yohei Mizuta, Kenji Yasuda, Shigeru Kohno

    Japanese Journal of Infectious Diseases   61 ( 4 ) 294 - 297  2008

    　View Summary

    Time-lapse video microscopic observation is useful for analysis of cell biology, especially in rapid response of immune cells. Dendritic cells (DCs) have multiple functions in the immune system, and DCs in peripheral blood play an especially important role at the front line of infection. We have developed a time-lapse video microscopic method for the evaluation of single myeloid DCs (MDC-1) from human peripheral blood. MDC-1 displayed generalized plasma membrane ruffling and phagocytosis of Pseudomonas aeruginosa. The morphological changes of MDC-1 increased following stimulation with P. aeruginosa but not after stimulation with supernatant from a P. aeruginosa culture. The activation of these morphological changes in MDC-1 could be quantitatively analyzed using the time-lapse video microscopy. This novel system may be useful for the evaluation of rapid response with human immune cells against bacterial infection.

    PubMed

  • アプタマーを用いた可逆的標識による細胞分離技術の開発(Simple repeatable noninvasive cell separation method using aptamer-conjugated magnetic microbeads and nuclease digestion)

    安西 悠, 寺薗 英之, 安田 賢二

    生物物理   47 ( Suppl.1 ) S57 - S57  2007.11

  • コラーゲントンネルを用いた血液脳関門モデルの構築(In vitro blood-brain barrier model using collagen micro flow channel)

    柴田 克也, 寺薗 英之, 服部 明弘, 安田 賢二

    生物物理   47 ( Suppl.1 ) S289 - S289  2007.11

  • マウス心筋細胞拍動能に対するHERG channelの作用(Effects of HERG channel on mouse cardiomyocyte beating ability)

    安東 賢太郎, 金子 智行, 野村 典正, 鈴木 郁郎, 北村 哲生, 林 純子, 松井 等, 安田 賢二

    生物物理   47 ( Suppl.1 ) S166 - S166  2007.11

  • 線維芽細胞を介した心筋2細胞間電位変化における伝導遅延時間測定(Measurement of the delay time of the action potential in two cardiomyocytes through fibroblasts)

    金子 智行, 鈴木 郁郎, 安東 賢太郎, 野村 典正, 北村 哲生, 林 純子, 安田 賢二

    生物物理   47 ( Suppl.1 ) S166 - S166  2007.11

  • On-chip multichannel action potential recording system for electrical measurement of single Neurites of neuronal network

    Ikurou Suzuki, Akihiro Hattori, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   46 ( 41-44 ) L1028 - L1031  2007.11  [Refereed]

    　View Summary

    We have developed a multielectrode array recording system for single-neurite-firing measurement using an artificially constructed neuronal network on a chip, which has a Wpm diameter array with electrodes spaced at 50 mu m, for noninvasive 64-channel 100 kHz multirecording and the stimulation of a plurality of neurites extending from a single neuron. To improve the signal/noise ratio, the ground plane was set on the multi-electrode-array plane and platinum black was set on each of the Wpm electrodes. Using this system, we performed a multisite recording of neurites of a single neuron of a rat hippocampal network in cases of both spontaneous firing and evoked responses to electrical stimulations, and estimated the velocity of action potential propagation among neurites of a single neuron from six recording sites. This demonstrated the potential use of our low-noise chip and our high-speed measurement system for the analysis of neuronal network activities at the single-neuron level.

    DOI

  • Measuring the sizes of nanospheres on a rough surface by using atomic force microscopy and a curvature-reconstruction method

    Koudai Oikawa, Hyonchol Kim, Naoya Watanabe, Masatsugu Shigeno, Yoshiharu Shirakawabe, Kenji Yasuda

    ULTRAMICROSCOPY   107 ( 10-11 ) 1061 - 1067  2007.10  [Refereed]

    　View Summary

    One of the advantages of atomic force microscopy (AFM) is that it can accurately measure the heights of targets on flat substrates. It is difficult, however, to determine the shape of nanoparticles on rough surfaces. We therefore propose a curvature-reconstruction method that estimates the sizes of particles by fitting sphere curvatures acquired from raw AFM data. We evaluated this fitting estimation using 15-, 30-, and 50-nm gold nanoparticles on mica and confirmed that particle sizes could be estimated within 5% from 20% of their curvature measured using a carbon nanotube (CNT) tip. We also estimated the sizes of nanoparticles on the rough surface of dried cells and found we also can estimate the size of those particles within 5%, which is difficult when we only used the height information. The results indicate the size of nanoparticles even on rough surfaces can be measured by using our method and a CNT tip. (c) 2007 Elsevier B.V. All rights reserved.

    DOI

  • Simple non-invasive cell separation method using magnetic aptamer-conjugated microbeads and nuclease digestion

    Yasuda K

    Journal of Biological Physics and Chemistry   7 ( 3 ) 83 - 86  2007.09

    DOI

  • Constructive formation and connection of aligned micropatterned neural networks by stepwise photothermal etching during cultivation

    Ikurou Suzuki, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS   46 ( 9B ) 6398 - 6403  2007.09  [Refereed]

    　View Summary

    To understand the topologically dependence of neural network function and its community effects, a constructive approach to forming a model culture system in which we can fully control the spatiotemporal pattern modification during cultivation is useful. We thus newly developed an on-chip multi-electrode array (MEA) system combined with an agarose microchamber (AMC) array to record the firing at multiple cells simultaneously over a long term and to topographically control the cell positions and their connections in order to form two linearly aligned micropatterned networks using additional photothermal etching during cultivation. The electrical connection through the additional neurite connection between two networks in both synchronized spontaneous firings and evoked responses to electrical stimulation was measured, and the localized synaptogenesis at the additional connection point and the propagation by chemical synapses were confirmed. The results show the advantages of AMC/MEA cultivation and measurement methods and indicate they will be useful for investigating community effects by pattern modification during cultivation.

    DOI

  • Origin of individuality of two daughter cells during the division process examined by the simultaneous measurement of growth and swimming property using an on-chip single-cell cultivation system

    Senkei Umehara, Ippei Inoue, Yuichi Wakamoto, Kenji Yasuda

    BIOPHYSICAL JOURNAL   93 ( 3 ) 1061 - 1067  2007.08  [Refereed]

    　View Summary

    We examined the origin of individuality of two daughter cells born from an isolated single Escherichia coli mother cell during its cell division process by monitoring the change in its swimming behavior and tumbling frequency using an on-chip single-cell cultivation system. By keeping the isolated condition of an observed single cell, we compared its growth and swimming property within a generation and over up to seven generations. It revealed that running speed decreased as cell length smoothly increased within each generation, whereas tumbling frequency fluctuated among generations. Also found was an extraordinary tumbling mode characterized by the prolonged duration of pausing in predivisional cells after cell constriction. The observed prolonged pausing may imply the coexistence of two distinct control systems in a predivisional cell, indicating that individuality of daughter cells emerges after a mother cell initiates constriction and before it gets physically separated into two new cell bodies.

    DOI PubMed

  • Dependence of the community effect of cultured cardiomyocytes on the cell network pattern

    Tomoyuki Kaneko, Kensuke Kojima, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   356 ( 2 ) 494 - 498  2007.05  [Refereed]

    　View Summary

    To elucidate the role of the community effect in cardiomyocytes, we developed an on-chip single-cell-based culture system with which the dynamics of the change of beat rate and beat rate fluctuation of cultured cardiomyocytes can be measured at the single-cell level before and after the formation of a cell network. We examined the dependence of the community effect on cell network pattern by culturing cardiomyocytes in differently shaped microchambers and investigated the relation between the network pattern and the stability of the beat rate. We found that beat rate fluctuation tends to decrease as cell-community size increases, irrespective of cell network pattern. This indicates that on-chip single-cell-based cardiomyocyte communities might be able to model a heart tissue accurately enough to be used in practical applications such as drug screening. (c) 2007 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Asynchrony in the growth and motility responses to environmental changes by individual bacterial cells

    Senkei Umehara, Akihiro Hattori, Ippei Inoue, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   356 ( 2 ) 464 - 469  2007.05  [Refereed]

    　View Summary

    Knowing how individual cells respond to environmental changes helps one understand phenotypic diversity in a bacterial cell population, so we simultaneously monitored the growth and motility of isolated motile Escherichia coli cells over several generations by using a method called on-chip single-cell cultivation. Starved cells quickly stopped growing but remained motile for several hours before gradually becoming immotile. When nutrients were restored the cells soon resumed their growth and proliferation but remained immotile for up to six generations. A flagella visualization assay Suggested that deflagellation underlies the observed loss of motility. This set of results demonstrates that single-cell transgenerational study under well-characterized environmental conditions can provide information that will help us understand distinct functions within individual cells. (c) 2007 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Detection of tetanus-induced effects in linearly lined-up micropatterned neuronal networks: Application of a multi-electrode array chip combined with agarose microstructures

    Ikurou Suzuki, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   356 ( 2 ) 470 - 475  2007.05  [Refereed]

    　View Summary

    One of the best approaches to understanding the mechanism of information acquisition and storage is to characterize the plasticity of network activity by monitoring and stimulating individual neurons in a topologically defined network and doing this for extended periods of time. We therefore previously developed an on-chip multi-electrode array (MEA) system combined with an array of agarose microchambers (AM,Cs). It is possible to record the firing at multiple cells simultaneously for long term and topographically control the cells position and their connections. In our present study, we demonstrated the effect of tetanic stimulation in a linearly lined-up patterned network on the AMC/MEA chip. We detected reproducible activity changes that were induced by tetanic stimulation and saw that these changes were maintained for 6-24 h. The results show the advantage of our ANIC/MEA cultivation and measurements methods and suggest they will be useful for investigating the long-term plasticity depending on network topology and size. @ 2007 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Identification of size differences of gold nanoparticles on cell surface by curvature reconstruction method using atomic force microscopy

    Hyonchol Kim, Koudai Oikawa, Naoya Watanabe, Masatsugu Shigeno, Yoshiharu Shirakawabe, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   46 ( 8-11 ) L184 - L186  2007.03  [Refereed]

    　View Summary

    We have developed a curvature reconstruction method (CRM) for the size estimation of nanoparticles attached and sunk into the rough surface of cells by fitting the curvature of such particles' outer shapes measured using sectional height images obtained by atomic force microscopy (AFM). A dried cell surface, on which a mixture of 30 and 50 nm gold particles was placed, was traced by AFM using a carbon nanotube (CNT) tip to estimate particle size distribution using CRM, and particle size distribution was also measured by field-emission scanning electron microscopy (FE-SEM) for confirmation. The results showed the CRM-estimated diameters of the nanoparticles were within an error,of 7.57 +/- 5.41 nm independent of the difference in the sizes of particles, indicating that (1) a set of nanometer-sized marker probes with 20 nm differences in diameter can be distinguished even on the rough surface of cells, and that (2) errors might be caused by the offset of traces of particle curvature indicated by the shape of the CNT tip used.

    DOI

  • Chaotropic etching for fabricating microwells for cell culture

    Nobuhiro Tamai, Hiroyuki Moriguchi, Yuzo Takayama, Yasuhiko Jimbo, Ikuro Suzuki, Kenji Yasuda

    IEEJ Transactions on Electronics, Information and Systems   127 ( 10 )  2007

    　View Summary

    Formation of simple neuronal networks in vitro is one of the promising methods to study biological information processing. Agarose microchambers have several advantages to form and maintain simple network structures. Here, in this work, a novel method for fabricating microwells in an agarose-layer is reported. Chaotropic effects of sodium iodide (NaI) is applied for etching agarose films. A conventional glass micropipette filled with NaI solution was aligned and a small amount of NaI was ejected to surface of the film. The agarose was denatured by the soaked NaI. The denatured agarose was washed out by distilled water. The size of the well was determined by the quantity of ejected NaI solution and its diffusion time. Conditions for fabricating wells of 100 to 600 μm diameters were established. Multiple wells up to 100 were formed on a single surface sequentially by programmed movement of the microscope stage. Rat hippocampal neurons were successfully cultured in the wells. Combining this method with microelectrode-array substrates will enable us of recording neuronal activity from simple neuronal networks as well as co-culture systems of heterogeneous tissues.

    DOI

  • Rapid real-time PCR-based nucleotide sequence measurement method using 1480n m infrared laser heating

    H. Terazono, A. Hattori, H. Takei, K. Takeda, K. Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2007; 20th International Microprocesses and Nanotechnology Conference, MNC     326 - 327  2007

    DOI

  • Collagen micro flow channel for in vitro Blood-Brain Barrier model

    K. Shibata, H. Terazono, A. Hattori, K. Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2007; 20th International Microprocesses and Nanotechnology Conference, MNC     510 - 511  2007

    　View Summary

    We fabricated micro flow channel based on the collagen tunnel for in vitro BBB blood capirary model using collagen gel tunnel, PDMS and infrared laser. This flow channel system can add the influence of shear stress to EC and evaluate the permeability by continuous microfluidic flow during cultivation. This system is expected to become a novel tool for emulating in vivo permeability of drug candidates available only in small quantities.

    DOI

  • Quantitative observation of membrane-attached bio-molecules on a cell surface using gold nano-particle and atomic force microscopy

    Hyonchol Kim, Koudai Oikawa, Kenji Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2007; 20th International Microprocesses and Nanotechnology Conference, MNC     274 - 275  2007

    DOI

  • An on-chip cardiomyocyte cell network assay for stable drug screening regarding community effect of cell network size

    Tomoyuki Kaneko, Kensuke Kojima, Kenji Yasuda

    ANALYST   132 ( 9 ) 892 - 898  2007  [Refereed]

    　View Summary

    We investigate the effect of haloperidol on a four-cell and nine-cell cardiomyocyte network on an agarose microchamber array chip to evaluate a cell-based model for drug screening. Using a network of cardiomyocytes whose beating intervals were stable and relatively uniform ( they only fluctuated 10% from the mean beating interval), we easily observed the effect of haloperidol on the cell network beating interval 5 min after administering it. We also observed the beating interval returned to its original state 10 min after the haloperidol was washed out of the chip. Although the four-cell network showed the unstable recovery of its beating rhythm after washout of haloperidol, the nine-cell network recovered completely to the stable original beating rhythm even after a second administration of haloperidol. The results indicate the importance of the community size in cell networks used in the stable cell-based screening model. Moreover, they indicate the advantage of using direct cell-based measurements in which the amount of drug administered and the time course over which it is administered are strictly controlled for evaluating the quantitative chemical effects of drugs on cells.

    DOI PubMed

  • Epigenetic inheritance of elongated phenotypes between generations revealed by individual-cell-based direct observation

    Yuichi Wakamoto, Kenji Yasuda

    MEASUREMENT SCIENCE AND TECHNOLOGY   17 ( 12 ) 3171 - 3177  2006.12  [Refereed]

    　View Summary

    A cellular phenotype is considered to be determined not only by genetic information but also by convoluted information on past states of a cell and its ancestors, i.e. hysteresis. This 'hysteretic effect' forms the basis of epigenetic phenomena. To understand these phenomena by which cells transmit certain phenotypes to descendants, it is necessary to observe individual cells and compare the phenotypes of each between generations under stringently controlled environmental conditions. We, therefore, did an individual-cell-based differential assay using Escherichia coli as a model organism. We observed normal-sized isolated cells change into elongated phenotypes, and subsequently measured the transmission of their characteristics between generations. This change occurred when the final length of the normal cells exceeded their cell-length boundary, i.e., 10 mu m with 5% probability. Once a cell became elongated, it divided unequally, producing two daughter cells; one was elongated and the other was normal. The elongated daughter transmitted the elongated phenotype to one lineage of the descendants by repeating unequal cell divisions with an average interdivision time half that of the normal phenotype, whereas the normal daughter retained normal phenotypic characteristics. The results suggest one possible non-genetic inheritance of cellular characteristics where phenotypic differences can only be inherited by geometrical information, independent of specific gene regulation.

    DOI

  • Role of the community effect of cardiomyocyte in the entrainment and reestablishment of stable beating rhythms

    Kensuke Kojima, Tomoyuki Kaneko, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   351 ( 1 ) 209 - 215  2006.12  [Refereed]

    　View Summary

    To investigate the roles that the community effect and entrainment function of cultured cardiomyocyte play in decreasing beating fluctuation and reestablishing synchronized beating, we developed a single-cell-based two-dimensional network culture assay to measure and compare the dynamics of beating rhythm synchronization of individual cells before and after they form networks. Studying the formation of two-cell networks, we found that their synchronized beating tended to be determined by the cardiomyocyte whose beat rate fluctuated less than that of the other cardiomyocyte. We further found that the strength of this tendency increased with the number of cells in the network. These results indicate that (1) beating fluctuation is one of the important factors influencing the reestablishment of a stable synchronous beating rhythm, (2) the larger networks reduce fluctuation, and (3) the formation of a spatial network can itself stabilize cardiomyocyte beat rates. (c) 2006 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Current rectification with poly-L-lysine-coated quartz nanopipettes

    Senkei Umehara, Nader Pourmand, Chris D. Webb, Ronald W. Davis, Kenji Yasuda, Miloslav Karhanek

    NANO LETTERS   6 ( 11 ) 2486 - 2492  2006.11  [Refereed]

    　View Summary

    Ion current rectification with quartz nanopipette electrodes was investigated through the control of the surface charge. The presence and absence of a positively charged poly-L-lysine (PLL) coating resulted in the rectified current with opposite polarity. The results agreed with the theories developed for current-rectifying conical nanopores, suggesting the similar underlying mechanism among asymmetric nanostructure in general. This surface condition dependence can be used as the fundamental principle of multi-purpose real-time in vivo biosensors.

    DOI PubMed

  • Quantitative measurement of damage caused by 1064-nm wavelength optical trapping of Escherichia coli cells using on-chip single cell cultivation system

    Satoru Ayano, Yuichi Wakamoto, Shinobu Yamashita, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   350 ( 3 ) 678 - 684  2006.11  [Refereed]

    　View Summary

    We quantitatively examined the possible damage to the growth and cell division ability of Escherichia coli caused by 1064-nm optical trapping. Using the synchronous behavior of two sister E coli cells, the growth and interdivision times between those two cells, one of which was trapped by optical tweezers, the other was not irradiated, were compared using an on-chip single cell cultivation system. Cell growth stopped during the optical trapping period, even with the smallest irradiated power on the trapped cells. Moreover, the damage to the cell's growth and interdivision period was proportional to the total irradiated energy (work) on the cell, i.e., irradiation time multiplied by irradiation power. The division ability was more easily affected by a smaller energy, 0.36 J, which was 30% smaller than the energy that adversely affected growth, 0.54 J. The results indicate that the damage caused by optical trapping can be estimated from the total energy applied to cells, and furthermore, that the use of optical trapping for manipulating cells might cause damage to cell division and growth mechanisms, even at wavelengths under 1064 nm, if the total irradiation energy is excessive. (c) 2006 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Quantitative evaluation of cell-to-cell communication effects in cell group class using on-chip individual-cell-based cultivation system

    Yuichi Wakamoto, Kenji Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   349 ( 3 ) 1130 - 1138  2006.10  [Refereed]

    　View Summary

    Cell-to-cell communication is considered to underlie the coordinated behavior and the multicellularity of cell group class, which cannot be explained only by the knowledge of lower class of life system from molecule to individual cell, because they are determined by at least two different ways: diffusible chemical signals and their direct physical contacts. We show in this paper a new method of individual-cell-based cell observation that can estimate the role of cell-to-cell communication, diffusible chemical signals, and physical contacts as separated properties, by applying an on-chip individual-cell-based cultivation system. The exchange of stationary phase medium on isolated individual Escherichia coli from exponential phase medium and the control of physical contacts indicated that the cell-to-cell direct contact did not affect the growth rate; only the communication through diffusible signals affects the growth rates as Hill's equation manner. (c) 2006 Elsevier Inc. All rights reserved.

    DOI PubMed

  • Dynamics of yeast prion aggregates in single living cells

    Shigeko Kawai-Noma, Satoru Ayano, Chan-Gi Pack, Masataka Kinjo, Masasuke Yoshida, Kenji Yasuda, Hideki Taguchi

    GENES TO CELLS   11 ( 9 ) 1085 - 1096  2006.09  [Refereed]

    　View Summary

    Prions are propagating proteins that are ordered protein aggregates, in which the phenotypic trait is retained in the altered protein conformers. To understand the dynamics of the prion aggregates in living cells, we directly monitored the fate of the aggregates using an on-chip single-cell cultivation system as well as fluorescence correlation spectroscopy (FCS). Single-cell imaging revealed that the visible foci of yeast prion Sup35 fused with GFP are dispersed throughout the cytoplasm during cell growth, but retain the prion phenotype. FCS showed that [PSI+] cells, irrespective of the presence of foci, contain diffuse oligomers, which are transmitted to their daughter cells. Single-cell observations of the oligomer-based transmission provide a link between previous in vivo and in vitro analyses of the prion and shed light on the relationship between the protein conformation and the phenotype.

    DOI PubMed

  • Phagocytic response to fully controlled plural stimulation of antigens on macrophage using on-chip microcultivation system

    Kazunori Matsumura, Kazuki Orita, Yuichi Wakamoto, Kenji Yasuda

    Journal of Nanobiotechnology   4 ( 7 ) 1 - 6  2006.08

    　View Summary

    To understand the control mechanism of innate immune response in macrophages, a series of phagocytic responses to plural stimulation of antigens on identical cells was observed. Two zymosan particles, which were used as antigens, were put on different surfaces of a macrophage using optical tweezers in an on-chip single-cell cultivation system, which maintains isolated conditions of each macrophage during their cultivation. When the two zymosan particles were attached to the macrophage simultaneously, the macrophage responded and phagocytosed both of the antigens simultaneously. In contrast, when the second antigen was attached to the surface after the first phagocytosis had started, the macrophage did not respond to the second stimulation during the first phagocytosis
    the second phagocytosis started only after the first process had finished. These results indicate that (i) phagocytosis in a macrophage is not an independent process when there are plural stimulations
    (ii) the response of the macrophage to the second stimulation is related to the time" delay from the first stimulation. Stimulations that occur at short time intervals resulted in simultaneous phagocytosis, while a second stimulation that is delayed long enough might be neglected until the completion of the first phagocytic process. © 2006 Matsumura et al
    licensee BioMed Central Ltd.

    DOI

  • Photothermal microneedle etching: Improved three-dimensional microfabrication method for agarose gel for topographical control of cultured cell communities

    Hiroyuki Moriguchi, Kenji Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   45 ( 29-32 ) L796 - L799  2006.08  [Refereed]

    　View Summary

    We have developed a new three-dimensional (3D) microfabrication method for agarose gel, photothermal microneedle etching (PTMNE), by means of an improved photothermal spot heating using a focused 1064 nm laser beam for melting a portion of the agarose layer at the tip of the microneedle, where a photoabsorbent chromium layer is coated to be heated. The advantage of this method is that it allows the 3D control of the melting topography within the-thick agarose layer with a 2 Pin resolution, whereas conventional photothermal etching can enable only two-dimensional (2D) control on the surface of the chip. By this method, we can form the spheroid clusters of particular cells from isolated single cells without any physical contact with other cells in other chambers, which is important for measuring the community effect of the cell group from isolated single cells. When we set single cancer cells in microchambers of 100 mu m in diameter, formed in a 50-mu m-thick agarose layer, we observed that they grew, divided, and formed spheroid clusters of cells in each microchamber. The result indicates the potential of this method to be a fundamental technique in the research of multicellular spherical clusters of cells for checking the community effect of cells in 3D structures, such as the permeabilities of chemicals and substrates into the cluster, which is complementary to conventional 2D dish cultivation and can contribute to the cell-based screening of drugs.

    DOI

  • Methodological improvements of pyrosequencing technology

    Baback Gharizadeh, Michael Akhras, Nader Nourizad, Mehran Ghaderi, Kenji Yasuda, Pal Nyren, Nader Pourmand

    JOURNAL OF BIOTECHNOLOGY   124 ( 3 ) 504 - 511  2006.07  [Refereed]

    　View Summary

    Pyrosequencing technology is a rather novel DNA sequencing method based on the sequencing-by-synthesis principle. This bioluminometric, real-time DNA sequencing technique employs a cascade of four enzymatic reactions producing sequence peak signals. The method has been proven highly suitable for single nucleotide polymorphism analysis and sequencing of short stretches of DNA. Although the pyrosequencing procedure is relatively straightforward, users may face challenges due to varying parameters in PCR and sequencing primer design, sample preparation and nucleotide dispensation; such challenges are labor and cost intensive. In this study, these issues have been addressed to increase signal quality and assure sequence accuracy. (c) 2006 Elsevier B.V. All rights reserved.

    DOI PubMed

  • Fluorescence microscopic investigation on morphological changes of giant multilamellar vesicles induced by amphiphilic additives

    T Toyota, H Tsuha, K Yamada, K Takakura, K Yasuda, T Sugawara

    LANGMUIR   22 ( 5 ) 1976 - 1981  2006.02  [Refereed]

    　View Summary

    Adding an artificial bolaamphiphile to a dispersion of giant multilamellar vesicles (GMVs) made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) induced a cup-shaped deformation in GMVs accompanied by partial extrusion of the inner vesicle; thereafter, the deformed vesicles returned to their original shape. On the other hand, when the artificial bolaamphiphile together with a surfactant was added to the vesicular dispersion, these deformation and reformation dynamics were transmitted from the outer membranes in GMVs to the inner membranes until an intact inner vesicle was extruded out of the outer membrane. The microscopic aspects of these processes were investigated using amphiphiles tagged with individual fluorophores.

    DOI

  • On-chip cellomics assay: Artificial re-construction of tissue model for cell based drug discovery

    Kenji Yasuda

    Micro Total Analysis Systems - Proceedings of MicroTAS 2006 Conference: 10th International Conference on Miniaturized Systems for Chemistry and Life Sciences     1070 - 1075  2006

    　View Summary

    We began a series of studies aimed at developing methods and systems of analyzing epigenetic information in cells, as well as that of genetic information, to expand our understanding of how living systems are determined. The role of epigenetic information on cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behaviour observed under conditions chosen to reveal adaptation processes and community effects. A system of analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an 'algebraic' system (emphasis on temporal aspects) and as a 'geometric' system (emphasis on spatial aspects). The knowlege acquired from this study may lead to the use of cells that fully control practical applications like cell-based drug screening and the regeneration of organs. © 2006 Society for Chemistry and Micro-Nano Systems.

  • Stability of beating frequency in cardiac myocytes by their community effect measured by agarose microchamber chip

    Kensuke Kojima, Tomoyuki Kaneko, Kenji Yasuda

    Journal of Nanobiotechnology   3 ( 4 ) 1 - 6  2005.05

    　View Summary

    To understand the contribution of community effect on the stability of beating frequency in cardiac myocyte cell groups, the stepwise network formation of cells as the reconstructive approach using the on-chip agarose microchamber cell microcultivation system with photo-thermal etching method was applied. In the system, the shapes of agarose microstructures were changed step by step with photo-thermal etching of agarose-layer of the chip using a 1064-nm infrared focused laser beam to increase the interaction of cardiac myocyte cells during cultivation. First, individual rat cardiac myocyte in each microstructure were cultivated under isolated condition, and then connected them one by one through newly-created microchannels by photo-thermal etching to compare the contribution of community size for the magnitude of beating stability of the cell groups. Though the isolated individual cells have 50% fluctuation of beating frequency, their stability increased as the number of connected cells increased. And finally when the number reached to eight cells, they stabilized around the 10% fluctuation, which was the same magnitude of the tissue model cultivated on the dish. The result indicates the importance of the community size of cells to stabilize their performance for making cell-network model for using cells for monitoring their functions like the tissue model. © 2005 Kojima et al
    licensee BioMed Central Ltd.

    DOI

  • On-chip single-cell-based gene expression analysis using gold nano-particles

    Hyonchol Kim, Atsushi Kira, Hironobu Kohno, Kazunori Matsumura, Kazuki Orita, Koudai Oikawa, Tomoyuki Kaneko, Kazunori Okano, Kenji Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2005: 2005 International Microprocesses and Nanotechnology Conference   2005   44  2005

    　View Summary

    The properties of individual cells are thought to depend on the time course change of the number and the spatial distribution of regulatory molecules in cells. To understand the strict meaning of those roles of some particular sets of regulatory proteins, we need to measure both the phenotypical characteristics of cells and the quantitative amount of mRNAs in each of those individual cells. For that purpose, we have developed a novel method to measure the quantitative amount of mRNA expression in individual cells keeping their spatial distributions in the cell without any amplification process like PCR. In this method, a set of different sizes of gold nano-particles attached with different probe-DNA respectively were used as a set of probes to detect different mRNAs existing in a cell. At first, the optimum condition of the immobilization of probe-DNA onto the gold nano-particle surface was examined. Next, the selectivity of the probe-DNA immobilized onto the nano-particle was tested using complementary oligonucleotide molecules. We confirmed the several different kinds of gold nano-particle probes were hybridized with target oligonucleotides having complementary sequences with almost 100% selectively. For the counting and distinguishing each of the gold nano-particles, we used two different methods and compared: one is Atomic Force Microscopy and the other is Scanning Electron Microscopy. Quantitative detection of mRNAs in individual cells keeping their spatial distributions was then examined using the gold nano-particle-based detection system. In this meeting, we will present the results and will discuss about the potential and problems of this method for the single-cell-based quantitative expression analysis.

    DOI

  • Direct formation of homogeneous DNA-probe surface on polyimide thin film by vapor deposition polymerization

    Atsushi Kira, Hyonchol Kim, Yoshio Hasegawa, Yoshikazu Takahashi, Kazunori Okano, Kenji Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2005: 2005 International Microprocesses and Nanotechnology Conference   2005   204  2005

    　View Summary

    For the single-molecule level quantitative measurement of target mRNAs attached on the DNA chip, one of the most important things is how to maintain the homogeneous, desirable-spaced arrangement of DNA-probes on the surface of the chip. Thus we have developed the novel method for decorating DNA-probes on the chip with desired intervals and homogeneous concentration applying the vapor deposition polymerization (VDP) technique, in which hexamethylene diisocyanate (HDI) and 3,5-diaminobenzonic acid (DBA) molecules were polymerized directly on the chip to form the polymer thin layer. The interval of the reactive carboxyl-group (-COOH) on the side-chains of DBA was controlled to become 2.0 nm by choosing another molecule having this length (HDI). After we made 10-nm-thick HDI-DBA polymer film on the chip, we attached amine-group of the thiol-, amine-decorated DNA-probe to the carboxyl-group of DBA. Then we checked the spatial arrangement and homogeneity of DNA-probes attached on the polymer film using 20-nm gold (Au) nano-particles. By the scanning electric microscopy observation, we first confirmed the spatial distribution of Au nano-particles on the chip was 254 particles/μ m2, whereas the less than 1 particles/μ m2 for the control sample, in which no DNA-probe was attached on the film. Moreover, the standard deviation of localization of particle distribution was less than 8 particles differences / 254 particles/μ m2, which is a magnitude better than the conventional silane-coupling method. The result indicates the potential of our method to form the homogeneous DNA-probe surface on the.

    DOI

  • Stepwise pattern modification of neuronal network in photo-thermally-etched agarose architecture on multi-electrode array chip for individual-cell-based electrophysiological measurement

    Suzuki, I, Y Sugio, Y Jimbo, K Yasuda

    LAB ON A CHIP   5 ( 3 ) 241 - 247  2005  [Refereed]

    　View Summary

    We have developed a procedure for stepwise topographical control of network patterns and neurite connection directions between adjacent living neurons using an individual-cell-based on-chip multi-electrode array ( MEA) cell cultivation system with an agarose microchamber (AMC) array. This procedure enables flexible and precise control of the cell positions and easy and flexible control of the pattern modification of connections between the cells in AMCs through stepwise photo-thermal etching in which a portion of the agarose layer on the chip is melted with a 1480 nm infrared laser beam even during cultivation. With adequate laser power and this stepwise procedue, we can fabricate narrow micrometer-order grooves (microchannels) during cultivation in a stepwise manner. Using this procedure, we controlled the direction of elongation of axons and dendrites selectively and confirmed the direction by immunostaining. We also demonstrated electrophysiological one-way transmission of signals among aligned hippocampal neurons in which the directions of the neurite connections were controlled using this stepwise photo-thermal etching procedure. These results demonstrate the potential of full direction control of neurite connections between neurons using stepwise photo-thermal etching to form microchannels one by one in an on-chip AMC/MEA cell cultivation system. We can thus better understand the meaning of neuronal network patterns and connection directions.

    DOI PubMed

  • Using agarose microchamber system, measurements of community effects of the cardiomyocytes and the heterogeneous cell types

    Yasuda K

    Proceedings of The 6th International Conference on Intelligent Materials and Systems     183 - 186  2005

  • Single-cell growth and division dynamics showing epigenetic correlations

    Y Wakamoto, J Ramsden, K Yasuda

    ANALYST   130 ( 3 ) 311 - 317  2005  [Refereed]

    　View Summary

    The emergence of variation and subsequent inheritance of the emergent characteristics in a clonal population of bacteria is considered as evidence for epigenetic processes in the cell. We report here the results of experiments in which we quantitatively examined variations in single Escherichia coli cells with an identical genetic endowment in order to establish whether certain characteristics of single cells were inherited by their descendants maintained in a uniform environment. Significantly large variations of interdivision time, initial length, and final length were observed from generation to generation. Comparing the generations shows that interdivision time had no correlation with that of the consecutive generations, whereas those of initial length and final length were positively correlated with those of neighbouring generations.

    DOI PubMed

  • Biotechnology approach to determination of genetic and epigenetic control in cells

    Kenji Yasuda

    Journal of Nanobiotechnology   2 ( 11 ) 1 - 10  2004.11

    　View Summary

    A series of studies aimed at developing methods and systems for analyzing epigenetic information in cells are presented. The role of the epigenetic information of cells, which is complementary to their genetic information, was inferred by comparing the predictions of genetic information with the cell behaviour observed under conditions chosen to reveal adaptation processes and community effects. Analysis of epigenetic information was developed starting from the twin complementary viewpoints of cells regulation as an 'algebraic' system (emphasis on the temporal aspect) and as a 'geometric' system (emphasis on the spatial aspect). The knowlege acquired from this study will lead to the use of cells for fully controlled practical applications like cell-based drug screening and the regeneration of organs. © 2004 Yasuda
    licensee BioMed Central Ltd.

    DOI

  • 哺乳類におけるサーカディアンリズム中枢・視交叉上核の神経細胞の1細胞活動電位計測系の開発

    杉尾 嘉宏, 寺薗 英之, 鈴木 郁郎, 金子 智行, 中嶋 幹郎, 佐々木 均, 神保 泰彦, 安田 賢二

    生物物理   44 ( Suppl.1 ) S266 - S266  2004.11

  • On-chip single-cell observation assay for propagation dynamics of yeast Sup35 prionlike proteins

    S Ayano, S Noma, M Yoshida, H Taguchi, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   43 ( 11A ) L1429 - L1432  2004.11  [Refereed]

    　View Summary

    The cytoplasmically inherited genetic determinant [PSI+} of the yeast Saccharomyces cerevisiae is presumed to be a manifestation of the prionlike properties of the chromosome-encoded Sup35 protein. Here, we show the relationship between the cell growth and the inheritance of Sup35p-GFP aggregation using on-chip single-cell observation assay. When Sup35 was expressed by induction, an aggregation was started-after soluble Sup35-GFP in the cytoplasm reached to the critical concentration. Once the aggregation was generated, the concentration of free Sup35-GFP remained constant at a critical value. After stopping the Sup35-GFP induction by changing the cultivation buffer, the concentration of soluble Sup35-GFP remained constant, whereas the size of aggregation decreased. This result indicates that the aggregation of Sup35-GFP is a reversible growth/shrinking phenomenon with the same velocity constant as that for a forward/reverse reaction.

    DOI

  • A novel method of cultivating cardiac myocytes in agarose microchamber chips for studying cell synchronization

    Kensuke Kojima, Tomoyuki Kaneko, Kenji Yasuda

    Journal of Nanobiotechnology   2 ( 9 ) 1 - 4  2004.09

    　View Summary

    We have developed a new method that enables agar microstructures to be used to cultivate cardiac myocyte cells in a manner that allows their connection patterns to be controlled. Non-contact three-dimensional photo-thermal etching with a 1064-nm infrared focused laser beam was used to form the shapes of agar microstructures. This wavelength was selected as it is not absorbed by water or agar. Identical rat cardiac myocytes were cultured in adjacent microstructures connected by microchannels and the interactions of asynchronous beating cardiac myocyte cells observed. Two isolated and independently beating cardiac myocytes were shown to form contacts through the narrow microchannels and by 90 minutes had synchronized their oscillations. This occurred by one of the two cells stopping their oscillation and following the pattern of the other cell. In contrast, when two sets of synchronized beating cells came into contact, those two sets synchronized without any observable interruptions to their rhythms. The results indicate that the synchronization process of cardiac myocytes may be dependent on the community size and network pattern of these cells. © 2004 Kojima et al
    licensee BioMed Central Ltd.

    DOI

  • Modification of a neuronal network direction using stepwise photo-thermal etching of an agarose architecture

    Ikurou Suzuki, Yoshihiro Sugio, Hiroyuki Moriguchi, Yasuhiko Jimbo, Kenji Yasuda

    Journal of Nanobiotechnology   2 ( 7 ) 1 - 8  2004.07

    　View Summary

    Control over spatial distribution of individual neurons and the pattern of neural network provides an important tool for studying information processing pathways during neural network formation. Moreover, the knowledge of the direction of synaptic connections between cells in each neural network can provide detailed information on the relationship between the forward and feedback signaling. We have developed a method for topographical control of the direction of synaptic connections within a living neuronal network using a new type of individual-cell-based on-chip cell-cultivation system with an agarose microchamber array (AMCA). The advantages of this system include the possibility to control positions and number of cultured cells as well as flexible control of the direction of elongation of axons through stepwise melting of narrow grooves. Such micrometer-order microchannels are obtained by photo-thermal etching of agarose where a portion of the gel is melted with a 1064-nm infrared laser beam. Using this system, we created neural network from individual Rat hippocampal cells. We were able to control elongation of individual axons during cultivation (from cells contained within the AMCA) by non-destructive stepwise photo-thermal etching. We have demonstrated the potential of our on-chip AMCA cell cultivation system for the controlled development of individual cell-based neural networks. © 2004 Suzuki et al
    licensee BioMed Central Ltd.

    DOI

  • Non-destructive on-chip cell sorting system with real-time microscopic image processing

    Kazunori Takahashi, Akihiro Hattori, Ikurou Suzuki, Takanori Ichiki, Kenji Yasuda

    Journal of Nanobiotechnology   2 ( 5 ) 1 - 8  2004.06

    　View Summary

    Studying cell functions for cellomics studies often requires the use of purified individual cells from mixtures of various kinds of cells. We have developed a new non-destructive on-chip cell sorting system for single cell based cultivation, by exploiting the advantage of microfluidics and electrostatic force. The system consists of the following two parts: a cell sorting chip made of polydimethylsiloxane (PDMS) on a 0.2-mm-thick glass slide, and an image analysis system with a phase-contrast/fluorescence microscope. The unique features of our system include (i) identification of a target from sample cells is achieved by comparison of the 0.2-μm-resolution phase-contrast and fluorescence images of cells in the microchannel every 1/30 s
    (ii) non-destructive sorting of target cells in a laminar flow by application of electrostatic repulsion force for removing unrequited cells from the one laminar flow to the other
    (iii) the use of agar gel for electrodes in order to minimize the effect on cells by electrochemical reactions of electrodes, and (iv) pre-filter, which was fabricated within the channel for removal of dust contained in a sample solution from tissue extracts. The sorting chip is capable of continuous operation and we have purified more than ten thousand cells for cultivation without damaging them. Our design has proved to be very efficient and suitable for the routine use in cell purification experiments. © 2004 Takahashi et al
    licensee BioMed Central Ltd.

    DOI

  • On-chip single-cell-based microcultivation method for analysis of genetic information and epigenetic correlation of cells

    KJ Yasuda

    JOURNAL OF MOLECULAR RECOGNITION   17 ( 3 ) 186 - 193  2004.05  [Refereed]

    　View Summary

    We have developed an on-chip single-cell based microcultivation method for analyzing the variability of genetic information stored in single cells and their epigenetic correlations. The method uses four systems: an on-chip cell sorter for purifying the cells in a non-destructive manner; an on-chip single-cell cultivation chip for isolating single cells; an on-chip agarose microchamber system for constructive cell-cell network formation during cultivation; and an on-chip single-cell-based expression analysis system. Using these systems, we could measure the variability of prokaryotic cells and eukaryotic cells having the same DNA and found that, although prokaryotic cells have a large variability in their interdivision times, sister eukaryotic cells having the same DNA synchronized well. We also measured the dynamics of synchronization of beating cardiac myocytes and found that two isolated cells synchronize by one cell following the other after a short pause in beating. These results showed the potential of the on-chip microcultivation method's constructive approach to analyzing cell systems. Copyright (C) 2004 John Wiley Sons, Ltd.

    DOI PubMed

  • A 1480/1064 nm dual wavelength photo-thermal etching system for non-contact three-dimensional microstructure generation into agar microculture chip

    A Hattori, H Moriguchi, S Ishiwata, K Yasuda

    SENSORS AND ACTUATORS B-CHEMICAL   100 ( 3 ) 455 - 462  2004.05  [Refereed]

    　View Summary

    We have developed a new type of non-contact three-dimensional photo-thermal etching method for agar microculture chips exploiting the characteristics of two different wavelengths of infrared laser beams. We used two different wavelengths of infrared (1480 and 1064 nm) focused laser beam as a heat source to melt and remove a portion of 200 mum high agar gel layer on the 5 nm thick chromium-coated glass slide. As the 1480 nm infrared beam is absorbed by water, the agar gel on the light pathway is heated and melted. On the other hand, as the 1064 nm infrared beam is not absorbed by water and agar, the melting of the agar occurred just near the chromium thin layer that absorbs 1064 nm infrared light. Using this non-contact etching, we can easily make microstructures in agar-layer using infrared laser beam only within a few minutes; i.e. cell-culture holes are melted by 100 mW, 1480 nm laser and tunnels by 100 mum/s, 40 mW, 1064 nm laser, respectively. The size of holes and tunnels were also controlled by choosing the irradiation power and time of infrared lasers. Those results indicate that we can make and use microstructures for biological use without any expensive microfablication facilities nor a series of complicated procedure and time. (C) 2004 Elsevier B.V. All rights reserved.

    DOI

  • Simultaneous measurement of sensor-protein dynamics and motility of a single cell by on-chip microcultivation system

    Ippei Inoue, Daisuke Shiomi, Ikuro Kawagishi, Kenji Yasuda

    Journal of Nanobiotechnology   2 ( 4 ) 1 - 4  2004.04

    　View Summary

    Measurement of the correlation between sensor-protein expression, motility and environmental change is important for understanding the adaptation process of cells during their change of generation. We have developed a novel assay exploiting the on-chip cultivation system, which enabled us to observe the change of the localization of expressed sensor-protein and the motility for generations. Localization of the aspartate sensitive sensor protein at two poles in Escherichia coli decreased quickly after the aspartate was added into the cultivation medium. However, it took more than three generations for recovering the localization after the removal of aspartate from the medium. Moreover, the tumbling frequency was strongly related to the localization of the sensor protein in a cell. The results indicate that the change of the spatial localization of sensor protein, which was inherited for more than three generations, may contribute to cells, motility as the inheritable information. © 2004 Inoue et al
    licensee BioMed Central Ltd.

    DOI

  • An agar-based on-chip neural-cell-cultivation system for stepwise control of network pattern generation during cultivation

    Y Sugio, K Kojima, H Moriguchi, K Takahashi, T Kaneko, K Yasuda

    SENSORS AND ACTUATORS B-CHEMICAL   99 ( 1 ) 156 - 162  2004.04  [Refereed]

    　View Summary

    We have developed a new type of single-cell based on-chip cell-cultivation system with an agarose microchamber (AMC) array and a photo-thermal etching module for step-by-step topographical control of the network patterns of living neural cells during long-term cultivation The advantages of this system are that (1) it can control positions and numbers of cells for cultivation by using agar-based microchambers, and (2) it can change the neural network complexity during cultivation by photo-thermal melting a portion of agar at the focal point of a 1064 nm infrared laser beam. This laser wavelength is permeable with respect to water and agarose, and it is only absorbed at the thin chromium layer on the chromium-coated glass slide surface at the bottom of the agarose layer. With adequate laser power, we can easily fabricate narrow tunnel-shaped channels between. the microchambers at the bottom of the agar layer without the complicated steps conventional microfabrication processes entail even during cultivation; we demonstrated that rat hippocampal cells in two adjacent chambers formed fiber connections through new connections between chambers after these had been photo-thermally fabricated. We also verified the fiber connection between those cells by using calcium-based fluorescent microscopy. These results indicate that this system can potentially be used for studying the complexity of neural network patterns for epigenetic memorization. (C) 2003 Elsevier B.V. All rights reserved.

    DOI

  • Individual-cell-based electrophysiological measurement of a topographically controlled neuronal network pattern using agarose architecture with a multi-electrode array

    Suzuki, I, Y Sugio, Y Jimbo, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   43 ( 3B ) L403 - L406  2004.03  [Refereed]

    　View Summary

    We have developed a new type of individual-cell-based electrophysiological measurement method using an on-chip multielectrode array (MEA) cell-cultivation system with an agarose microchamber (AMC) array for topographical control of the network patterns of a living neuronal network. The advantages of this method are that it allows the recording of the firing of multiple cells simultaneously for weeks without contamination using the MEA, and that it allows control of the cell positions and numbers, and their connections for cultivation using AMCs with microchannels fabricated by photothermal etching where a portion of the agarose layer is melted with a 1480 nm infrared laser beam. Using this method, we formed an individual-cellbased neural network pattern of Rat,hippocampal cells within the AMC array without cells escaping from the electrode positions in the microchamber during a thirteen-day cultivation, and could record the cell firing of lined-up hippocampal cells in response to 20muA, 5 kHz stimulation via an electrode. This demonstrated the potential of our on-chip AMC/MEA cell cultivation method for long-term single-cell-based electrophysiological measurement of a neural network system for understanding the topographical meaning of neuronal network patterns.

    DOI

  • Simultaneous measurement of growth and movement of cells exploiting on-chip single-cell cultivation assay

    S Umehara, A Hattori, Y Wakamoto, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   43 ( 3 ) 1214 - 1217  2004.03  [Refereed]

    　View Summary

    We have developed an on-chip single-cell microcultivation assay as a means of simultaneously observing the growth and movement of single bacterial cells during long-term cultivation. This assay enables the direct observation of single cells captured in microchambers fabricated on thin glass slides and having semipermeable membrane lids, in which the cells can swim within the space without escape for the long periods. Using this system, the relationship between the cell cycle and the tendency of movement was observed and it was found that the mean free path length did not change during the cell cycle, and that the growth and the swimming were not synchronized. The result indicates that the ability of movement of the cells was independent of the cell cycle.

    DOI

  • Single-cell-based electrophysiological measurement of a topographically controlled neuronal network using agarose architecture with a multi-electrode array

    Ikurou Suzuki, Yoshihiro Sugio, Yasuhiko Jimbo, Kenji Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2004     220 - 221  2004

    DOI

  • Hysteresis of energy consumption of motility and growth in Escherichia coli

      43 ( 180 ) 28 - 33  2004

    DOI

  • On-chip neural cell cultivation using agarose-microchamber array constructed by a photothermal etching method

    H Moriguchi, K Takahashi, Y Sugio, Y Wakamoto, Inoue, I, Y Jimbo, K Yasuda

    ELECTRICAL ENGINEERING IN JAPAN   146 ( 2 ) 37 - 42  2004.01  [Refereed]

    　View Summary

    We have developed a novel method for on-chip cultivation of neural cells in a flexible agarose-microchamber array on a glass slide. The agarose microchamber is a micrometer-order cavity constructed on the surface of an agarose layer by molding a 50-mum-high square/circular micro-cast of thick SU-8 photoresist. In addition, the shape of the agarose microchamber was rearranged by using the photothermal etching method, in which we used an infrared (1064-nm) focused laser beam as the heat source to melt and remove a portion of agarose gel at the heating spot. With the photothermal etching method, we can also manufacture narrow tunnel-shaped channels between microchambers. When nerve cells were cultured on the agar-microchamber array chip, the nerve cells in two adjacent microchambers connected through the photothermal-etched channel after 48 hours of cultivation. Those results suggest the potential of an agarose-microchamber array integrated with the photothermal etching method for the next stage of single cell cultivation and measurement of nerve cells, such as real-time control of cell interactions during cultivation. (C) 2003 Wiley Periodicals, Inc.

    DOI

  • Pattern modification of a neuronal network for individual-cell-based electrophysiological measurement using photothermal etching of an agarose architecture with a multielectrode array

    I. Suzuki, Y. Sugio, H. Moriguchi, A. Hattori, K. Yasuda, Y. Jimbo

    IEE Proceedings Nanobiotechnology   151 ( 3 ) 116 - 121  2004

    　View Summary

    A new type of individual-cell-based on-chip multielectrode array (MEA) cell-cultivation system with an agarose microchamber (AMC) array for topographical control of the network patterns of a living neuronal network has been developed. The advantages of this system are that it allows control of the cell positions and numbers for cultivation using AMCs, as well as easy and flexible control of the pattern of connections between the AMCs through photothermal etching where a portion of the agarose layer is melted with a 1480nm infrared laser beam. With adequate laser power, narrow micrometer-order grooves (microchannels) can easily be fabricated that can be used to combine neighbouring AMCs to enable topographical control of the neural network pattern. Using this system, an individual-cell-based neural network pattern was formed of rat hippocampal cells within the AMC array without cells escaping from the electrode positions in the microchamber during an eight-day cultivation, and could record cell firing in response to 1.5V, 500kHz stimulation through an electrode. This demonstrated the potential of the on-chip AMC/MEA cell cultivation system for long-term single-cell-based electrophysiological measurement of a neural network system.

    DOI

  • Development of non-destructive, non-contact single-cell based differential cell assay using on-chip microcultivation and optical tweezers

    Y Wakamoto, S Umehara, K Matsumura, Inoue, I, K Yasuda

    SENSORS AND ACTUATORS B-CHEMICAL   96 ( 3 ) 693 - 700  2003.12  [Refereed]

    　View Summary

    We have investigated non-destructive, non-contact single-cell based differential cell screening method using on-chip microcultivation and optical tweezers. The four-room microchamber for cultivating four single cells consists of 5 mum high microstructure on the glass slide and is covered with semipermeable membrane to cultivate those cells under contamination-free condition. The number of cells in microchambers is controlled by using optical tweezers to pick out excess cells. For studying the actual changes occurring in cells under isolated condition, we measured and compared four cells in four microchambers simultaneously for more than 10 generations. To examine the potential of this method, we observed single cells of Escherichia coli for more than 10 generations. The results of these observations showed that they keep their mean values even though there exist large dynamic variations in interdivision time and growth speed. The simultaneous observations of four cells also confirmed that these variations in cells are not derived from the time-course changes of environmental conditions because those variations in four cells did not synchronized. The results suggested the potential use of our method for cell assay to predict whether the cells' variation is in permissible range or is caused by drugs or other environmental effects. (C) 2003 Elsevier B.V. All rights reserved.

    DOI

  • On-chip microcultivation chamber for swimming cells using visualized poly(dimethylsiloxane) valves

    K Takahashi, K Orita, K Matsumura, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   42 ( 9AB ) L1104 - L1107  2003.09  [Refereed]

    　View Summary

    We have developed a new type of on-chip microcultivation chamber made of poly(dimethylsiloxane) (PDMS) for long-term cultivation of swimming cells. The advantages of this chamber are that (1) the microfluidic channel width of the valve can be controlled according to air pressure while monitoring the microscopic image of the channel width, and that (2) a simple single-step procedure is required for the fabrication of the valve structure and microfluidic pathway. Using this chamber, we can control the passage of swimming Chlamydomonas cells, through the channel while visualizing the opening and closing of the valve as the medium buffer passes any time. Thus the long-term observation of the behavior of a particular single cell is accomplished.

    DOI

  • Flexible control of electrode pattern on cultivation chamber during cultivation of cells using nondestructive optical etching

    K Kojima, K Takahashi, T Kaneko, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   42 ( 8A ) L980 - L982  2003.08  [Refereed]

    　View Summary

    We have developed a method for flexible changing the shape of the electrode layer on a cultivation chip by nondestructive optical etching with a focused 1064 nm infrared laser during cultivation of cells on it. When the etched width of the scratch on the electrode layer of cultivation chip reached 10 mum, the conductance decreased to 0 S. The method was then examined for the area-specific stimulation of cardiac myocytes cultivated on the chip, and was founnd to stimulated the cells in the area successfully. The result indicates the ability of flexible-area-specific electric stimulation to change the shape of an electrode during cultivation.

    DOI

  • Role of timer and sizer in regulation of Chlamydomonas cell cycle

    K Matsumura, T Yagi, K Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   306 ( 4 ) 1042 - 1049  2003.07  [Refereed]

    　View Summary

    To estimate the role that time and size had in controlling the Chlamydomonas cell cycle, we used a new on-chip single-cell microcultivation system, which involved the direct observation of single cells captured in microchambers made on a thin glass slide. The dependence of the pattern of energy supply for cells on its cell cycle was examined through a series of different intensities of continuous illumination in a minimal medium, and we found that cell division occurred when cells reached the critical size, which was 2.2 times larger than that of the newly created cells. When illumination stopped before cells reached the critical size, even though growth had stopped, they continued dividing during the delay time, which was shorter when cells were larger. With re-illumination after darkness, cells began to grow again and the timing of cell division was again controlled by the critical size. This indicates that the co-existence of two cell cycle regulation mechanisms and the sizer mechanism had a stronger influence than the timer. (C) 2003 Elsevier Science (USA). All rights reserved.

    DOI PubMed

  • Differential analysis of cell cycle stability in Chlamydomonas using on-chip single-cell cultivation system

    K Matsumura, T Yagi, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   42 ( 7A ) L784 - L787  2003.07  [Refereed]

    　View Summary

    We have developed an on-chip microcultivation system for differential analysis of photosynthesizing cells of Chlamydomonas as a means of comparing the difference in interdivision time between sister cells and cells of adjacent generations having the same DNA and environment. The system enabled us to compare the change in the interdivision time of four sister cells simultaneously for several days, we found that the interdivision times of the four sister cells synchronize well, while, those of cells of subsequent generations do not. The result showed the potential of the system for measuring how much epigenctic information of eukaryotic cells can be conserved between sister cells. and cells of subsequent generations.

    DOI

  • Measurement of incident angle dependence of swimming bacterium reflection using on-chip single-cell cultivation assay

    A Hattori, S Umehara, Y Wakamoto, K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   42 ( 7B ) L873 - L875  2003.07  [Refereed]

    　View Summary

    We have developed an on-chip single-cell microcultivation assay as a means of continuously observing certain single swimming cells in order to trace their movement. The single cells were captured in microchambers fabricated on thin glass slides and having semipermeable membrane lids, in which cells can swim within the space for a long term without escaping. This assay enables the direct measurement of the reflection of certain cells against the microchamber walls depending on their incidence angles. Using this assay, the reflection was examined. We found that the ratio of reflection of cells to those of non-reverse was almost the same, though most of cells reflected when their incident angle was perpendicular to the wall.

    DOI

  • On-chip single-cell microcultivation assay for monitoring environmental effects on isolated cells

    S Umehara, Y Wakamoto, Inoue, I, K Yasuda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   305 ( 3 ) 534 - 540  2003.06  [Refereed]

    　View Summary

    We have developed a on-chip single-cell microcultivation assay as a means of observing the adaptation process of single bacterial cells during nutrient concentration changes. This assay enables the direct observation of single cells captured in microchambers made on thin glass slides and having semipermeable membrane lids, in which cells were kept isolated with optical tweezers. After changing a medium of 0.2% (w/v) glucose concentration to make it nutrient-free 0.9% NaCl medium, the growth of all cells inserted into the medium stopped within 20 min, irrespective of their cell cycles. When a nutrient-rich medium was restored, the cells started to grow again, even after the medium had remained nutrient-free for 42 h. The results indicate that the cell's growth and division are directly related to their nutrient condition. The growth curve also indicates that the cells keep their memory of what their growth and division had been before they stopped growing. (C) 2003 Elsevier Science (USA). All rights reserved.

    DOI PubMed

  • Stepwise pattern modification of neuronal network during cultivation using photo-thermal etching of agarose architecture

    Yoshihiro Sugio, Hiroyuki Moriguchi, Ikurou Suzuki, Tomoyuki Kaneko, Kenji Yasuda, Yasuhiko Jimbo

    Digest of Papers - Microprocesses and Nanotechnology 2003 - 2003 International Microprocesses and Nanotechnology Conference, MNC 2003     322 - 323  2003

    　View Summary

    We have developed a new type of on-chip cell cultivation system using an agarose microchamber (AMC) array and a photo-thermal etching method, thus enabling topographical control of neuronal network pattern step-by-step during cell cultivation. By using photo-thermal etching (micro melting) method, the number of microtunnel connecting microchambers can be easily increased, even during cell cultivation, according to the progress of the neuronal network formation. To demonstrate the capability of this system for topographical control of network formation, we cultured hippocampal neurons in this AMC array. We found that the cells in microchambers made fiber connections through microtunnels. Furthermore the cells even made fiber connections through additional microtunnels fabricated during cultivation by photo-thermal etching. The results showed that the photo-thermal etching could be used during cultivation without damaging cells.

    DOI

  • Developed on-chip cell sorting system based on an analysis of microscopic image and impact-free sorting for living cells

    K. Takahashi, A. Hattori, I. Suzuki, T. Ichiki, K. Yasuda

    Digest of Papers - Microprocesses and Nanotechnology 2003 - 2003 International Microprocesses and Nanotechnology Conference, MNC 2003     324 - 325  2003

    　View Summary

    In this paper, we have developed a newly developed on-chip cell sorting system that offers impact-free sorting for single-cell based observation analysis or regenerative medicine.

    DOI

  • Advanced photonics: Optical trapping techniques in bioanalysis

    Kenji Yasuda

    Biomedical Photonics: Handbook     61 - 1  2003.01

    　View Summary

    Knowledge about life processes has expanded dramatically during the 20th century and produced the modern disciplines of genomics and proteomics. However, there remains the great challenge of discovering the integration and regulation of living components in time and space within the cell. As we move into the postgenomic period, the complementarity between genomics and proteomics will become apparent, and the connections between them will be exploited, although genomics, proteomics, or their simple combination will not provide the data necessary to interconnect molecular events in living cells in time and space. The cells in a group are different entities, and differences arise even among cells grown in homogeneous conditions considered to have identical genetic information. These cells respond differently to perturbations. The question is why and how these differences arise. They might be caused by unequal distributions of biomolecules in cells, mutations, interactions between cells, fluctuations of environmental elements that affect the cell, etc. To understand the principle underlying the differences, keeping in mind the possibilities mentioned above, a system is necessary that would allow for the continuous observation of specific cells under fully controlled circumstances such as interactions between cells.

  • Two-dimensional network formation of cardiac myocytes in agar microculture chip with 1480 nm infrared laser photo-thermal etching

    K Kojima, H Moriguchi, A Hattori, T Kaneko, K Yasuda

    LAB ON A CHIP   3 ( 4 ) 292 - 296  2003  [Refereed]

    　View Summary

    We have developed a new method that enables agar microstructures to be used to cultivate cells and that allows cell network patterns to be controlled. The method makes use of non-contact three-dimensional photo-thermal etching with a 1480 nm infrared focused laser beam, which is strongly absorbed by water and agar gel, to form the shapes of agar microstructures. It allows microstructures to be easily formed in an agar layer within a few minutes, with cell-culture holes formed by the spot heating of a 100 mW laser and tunnels by the tracing of a 100 mm s(-1), 40 mW laser. We cultivated rat cardiac myocytes in adjacent microstructures and observed synchronized beating in them 90 min after they had made physical contact. Our results indicate that the system can make and use microstructures for cell-network cultivation in a minimal amount of time without any expensive microfabrication facilities or complicated procedures.

    DOI PubMed

  • On-chip Neural Cell Cultivation using Agarose-microchamber Array constructed by Photo-thermal Etching Method

      122 ( 9 ) 1453 - 1458  2002.09

    DOI

  • Development of On-chip Multi-electrode Neural Cell Cultivation System using Thick Photoresist SU-8 and Semi-permeable Membrane for Long Term Studies

      122 ( 9 ) 1447 - 1452  2002.09

    DOI

  • Morphological change of giant vesicles triggered by dehydrocondensation reaction

    K Takakura, T Toyota, K Yamada, M Ishimaru, K Yasuda, T Sugawara

    CHEMISTRY LETTERS   31 ( 3 ) 404 - 405  2002.03  [Refereed]

    　View Summary

    A giant vesicle composed of an amphiphile with a reactive site exhibited a morphological change when the vesicular amphiphile reacts with an added amphiphilic reaction-partner within its membrane.

    DOI

  • On-chip agarose-microchamber (AMC) array cell-cultivation system for topographical control of neural network

    Yasuda K

    Proceedings of Micro Total Analysis System Symposium 2002   1   13 - 15  2002

    DOI

  • An agar-microchamber cell-cultivation system: flexible change of microchamber shapes during cultivation by photo-thermal etching

    H Moriguchi, Y Wakamoto, Y Sugio, K Takahashi, Inoue, I, K Yasuda

    LAB ON A CHIP   2 ( 2 ) 125 - 130  2002  [Refereed]

    　View Summary

    A new type of cell-cultivation system based on photo-thermal etching has been developed for the on-chip cultivation of living cells using an agarose microchamber array. The method can be used to flexibly change the chamber structure by photo thermal etching, even during the cultivation of cells, depending upon the progress in cell growth. We used an infrared (1064 nm) focused laser beam as a heat source to melt and remove agar gel at the heated spot on a thin chromium layer. The melting of the agar occurred just near the chromium thin layer, and the size of the photo thermally etched area depended almost linearly on the power of the irradiated laser beam from 2 m m to 50 m m. Thus by using photo-thermal etching with adequate laser power we could easily fabricate narrow tunnel-shaped channels between the microchambers at the bottom of the agar-layer even during cell cultivation. After 48 h of cultivation of nerve cells, the nerve cells in two adjacent chambers made fiber connections through the fabricated narrow tunnel-shaped channels. These results suggest that photo-thermal etching occurred only in the area where an absorbing material was used, which means that it is possible to photo-thermally etch lines without damaging the cells in the microchambers. The results also suggest that the agar-microchamber cell cultivation system in combination with photo-thermal etching can potentially be used for the next stage of single cell cultivation including the real-time control of the interaction of cells during cell cultivation.

    DOI

  • Non-genetic variability of division cycle and growth of isolated individual cells in on-chip culture system

    Inoue, I, Y Wakamoto, K Yasuda

    PROCEEDINGS OF THE JAPAN ACADEMY SERIES B-PHYSICAL AND BIOLOGICAL SCIENCES   77 ( 8 ) 145 - 150  2001.10  [Refereed]

    　View Summary

    To investigate the non-gene tic variability of the division cycle and growth of single cells, we compared pairs of Escherichia coli daughter cells' growth and division time under isolated conditions using a newly developed on-chip culture system. The advantages of the system are: (i) continuous cultivation of isolated single cells or a group of cells in pm-sized micro-cages under isolated contamination-free and exchangeable medium conditions, and (ii) continuous observation and comparison of those floating daughter cells at a spatial resolution of 0.2 mum by phase-contrast/fluorescence microscopy and digital image processing. Using this system, cell growth and division time of daughter cells from an isolated mother cell were measured. A broad distribution of the cell division time and the division time differences of two daughter cells from the same mother cells were found. They are not attributable to a difference in DNA. The same tendency of broad distribution of the division time and the division time differences suggests the involvement of a probabilistic process to start the division.

    DOI

  • Development of bio-MEMS devices for single cell expression analysis

    T. Ichiki, T. Hara, T. Ujiie, Y. Horiike, K. Yasuda

    2001 International Microprocesses and Nanotechnology Conference, MNC 2001     190 - 191  2001

    　View Summary

    In order to provide total systems for single cell expression analysis, we have been developing a set of technology including cell cultivation, cell sorting, gene analysis from a specific cell, etc., using microfabrication technology. In this paper, we present the development of a cell sorter chip used as the core technology for establishing the cell sorting system that can separate and collect an individual cell according to its biological or biochemical information.

    DOI

  • On-chip single-cell cultivation system

    Y. Wakamoto, I. Inoue, H. Moriguchi, K. Yasuda

    Seikagaku   73 ( 12 ) 1439 - 1443  2001

    PubMed

  • Recovery of DNA Fragment from a DNA Probe Array

    Kazunori Okano, Gang Chen, Yoshinobu Kohara, Tomoharu Kajiyama, Kenji Yasuda, Shin'ichi Ishiwata

    IEEJ Transactions on Sensors and Micromachines   121 ( 4 ) 181 - 186  2001

    　View Summary

    Molecular biology is moving rapidly towards the stage of functional genomics in which rapid preparations of expressed messages (mRNA) will be required. If a DNA library is constructed on a solid support (DNA probe array) and any kind of expressed messages can be individually recovered from the probe array, DNA probe array will become a very useful method. Consequently, we developed a DNA preparation method using a DNA probe array that utilizes photo-thermal denaturation to recover specific DNA. The protocol for preparing DNA probe array was investigated to realize the stable immobilization of DNA probes on the surface of solid support. We used a glass plate coated with Cr (5-10 nm thick). The Cr surface was modified with 3-glysidoxypropyltrimethoxysilane to introduce active residues that can couple with amino residues at the 5' termini of DNA probes. The Cr surface acts as a photo-thermal transducer. The preparation method of DNA uses infrared (1053-nm) laser irradiation to thermally denature and release DNA immobilized in a specific area of a DNA probe array. Different DNA fragments fixed in place on the DNA probe array could be separately recovered. There were enough quantities of recovered DNA that can be amplified by using PCR. © 2001, The Institute of Electrical Engineers of Japan. All rights reserved.

    DOI

  • Analysis of single-cell differences by use of an on-chip microculture system and optical trapping

    Yuichi Wakamoto, Ippei Inoue, Hiroyuki Moriguchi, Kenji Yasuda

    Analytical and Bioanalytical Chemistry   371 ( 2 ) 276 - 281  2001

    　View Summary

    A method is described for continuous observation of isolated single cells that enables genetically identical cells to be compared
    it uses an on-chip microculture system and optical tweezers. Photolithography is used to construct microchambers with 5-μm-high walls made of thick photoresist (SU-8) on the surface of a glass slide. These microchambers are connected by a channel through which cells are transported, by means of optical tweezers, from a cultivation microchamber to an analysis microchamber, or from the analysis microchamber to a waste microchamber. The microchambers are covered with a semi-permeable membrane to separate them from nutrient medium circulating through a "cover chamber" above. Differential analysis of isolated direct descendants of single cells showed that this system could be used to compare genetically identical cells under contamination-free conditions. It should thus help in the clarification of heterogeneous phenomena, for example unequal cell division and cell differentiation. © Springer-Verlag 2001.

    DOI PubMed

  • On-chip culture system for observation of isolated individual cells

    Inoue, I, Y Wakamoto, H Moriguchi, K Okano, K Yasuda

    LAB ON A CHIP   1 ( 1 ) 50 - 55  2001  [Refereed]

    　View Summary

    To investigate the properties of isolated single cells with their environment, we developed the differential analysis method for single cells using an on-chip microculture system. The advantages of the system are, (i) continuous cultivation of a series of isolated single cells or a group of cells under contamination free conditions, (ii) continuous observation and comparison of those cells with 0.2 mum spatial resolution by a phase-contrast/fluorescent microscopy system with digital image processing. The core of the system is an n x n (n = 20-50) array of chambers, where each is 20-70 mum in diameter and 5-30 mum deep holes etched into a biotin-coated 0.17 mm thick glass slide. The biotin-coated glass slide is covered with the streptavidin coated cellulose semipermeable membrane, which is fixed on the surface of the glass slide by streptavidin-biotin attachment, separating those holes from the nutrient medium circulating through a 'cover chamber' above. A single cell or group of cells can thus be isolated from environment perfused with the same medium, and the medium in each chamber can be changed within the diffusion time (&lt;1/30 s). In addition, the microchamber volumes of specific cells or cell groups can be controlled by the sizes of the chambers. By using this system we found that the length of isolated Escherichia coli increased at 0.06 &mu;m min(-1) between cell divisions regardless of the chamber volume, and that the cell concentration reached 10(12) cells ml(-1) under contamination free conditions. The system is thus particularly useful for one cell level analysis because the direct descendants of single cells can be cultured and compared in the isolated microchambers, and the physical properties of the cells in each microchamber can be continuously observed and compared.

    DOI PubMed

  • Position-specific release of DNA from a chip by using photothermal denaturation

    K Okano, K Yasuda, S Ishiwata

    SENSORS AND ACTUATORS B-CHEMICAL   64 ( 1-3 ) 88 - 94  2000.06  [Refereed]

    　View Summary

    A photothermal method to recover specific DNA fragments fixed in place on a DNA chip is described. This method uses infrared (IR) laser irradiation to thermally denature and release specific DNA immobilized in a specific area of a chip. A 1053-nm IR laser beam with an intensity of 10-100; mW is focused on the target area at a resolution of 10 mu m, and the DNA fragments are released from the chip surface. We have demonstrated that DNA fragments containing different numbers of base pairs (231-799 bp) fixed in place on the DNA chip can be separately recovered. There are enough quantities of recovered DNA fragments that can be amplified by using polymerase chain reaction (PCR). The photothermal method coupled with the DNA chip can therefore be used in highly sensitive purification of DNA and will have many applications in the DNA chip technology. (C) 2000 Elsevier Science S.A. All rights reserved.

    DOI

  • Non-destructive, non-contact handling method for biomaterials in micro-chamber by ultrasound

    K Yasuda

    SENSORS AND ACTUATORS B-CHEMICAL   64 ( 1-3 ) 128 - 135  2000.06  [Refereed]

    　View Summary

    We investigated the non-contact handling of micrometer-sized samples in the micro-chamber using acoustic radiation force for lining up the microparticles and for mixing solutions. The chamber for handling samples consists of a fused quartz cell attaching a pair of 3.5 MHz lead zirconate titanate (PZT) transducers both sides. For lining up the particles, pure water containing 7-mu m polystyrene spheres was introduced into the chamber. When 3.5 MHz ultrasound was irradiated into the chamber, the particles lined up at the pressure node of ultrasound less than 0.3 mu m of the spatial distribution. For mixing, samples such as erythrocytes and fluorescent dye were introduced into the chamber from the inlet which arranged at the side wall of the chamber and the laminar flow of the two different kinds of solutions keeping their boundaries is observed. When the 3.5 MHz ultrasound irradiation into the chamber started, the boundaries of the two sample's flow were broken and the erythrocytes spread and mixed into all the span of the chamber. The possible damage caused by the 3.5 MHz ultrasound during the mixing process was also measured, and no significant release of the erythrocyte's component was detected even without the degas process, which was pre-processed for preventing cavitation generation. The results suggested the potential use of acoustic radiation force for non-contact, non-destructive and time-resolved handling method for micro-chamber as the sample preparation process. (C) 2000 Elsevier Science S.A. All rights reserved.

    DOI

  • Focal extraction of surface-bound DNA from a microchip using photo-thermal denaturation

    K Yasuda, K Okano, S Ishiwata

    BIOTECHNIQUES   28 ( 5 ) 1006 - +  2000.05  [Refereed]

    　View Summary

    High-throughput, selective extraction of a particular DNA fragment from a mixture of DNA before PCR amplification is becoming increasingly important in the DNA analysis field. Although the latest microchip technology has enabled real-time DNA expression analysis using hybridization between surface-bound probe DNA and sample DNA, the potential of this technology in purification of a small amount of DNA has not been demonstrated. We report here a method for area-selective release and collection of specific DNA, in which an IR laser beam is focused onto surface-bound sample DNA at the target-spotted area to denature hybridized DNA. First, sample DNA labeled with a fluorescent dye was hybridized to a probe DNA immobilized on a chromium-coated chip. A 1053-nm IR laser beam with an intensity of 10-100 mW was then focused on the target area with a spatial resolution of 10 mu m, causing the release of the fluorophore-labeled sample DNA as a result of photo-thermal denaturation. Confirmation of the amount of eluted DNA by PCR amplification after collection indicated that more than 10(-20) mol DNA/mu m(2) area was eluted from the microchip, representing more than 70% of the chip-bound sample DNA. These results indicate that this method can be applied to the highly sensitive purification of DNA ill microchip technology.

    DOI PubMed

  • Measurement of microscopic spatial distribution of acoustic radiation force using microspheres and electrostatic force

    K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   38 ( 5B ) 3316 - 3319  1999.05  [Refereed]

    　View Summary

    A simple method for measuring the microscopic spatial distribution of the acoustic radiation force by exploiting the competition between the acoustical radiation force and the electrostatic force on charged microspheres is investigated. First, the effective charge of polystyrene spheres is measured by monitoring the mobility of the particles in the 1 Hz, 13.4 V-pp/mm alternating electric field. Next, the shift of the particles away from the sound pressure node with an increase in intensity of the electrostatic force is observed by optical microscopy, and finally the acoustic radiation force is estimated. In the experiment, the spatial distribution of the acoustic radiation force in the 500 kHz, 80 Vpp standing wave was proportional to the sine curve, and had the same tendency as the result obtained from calculation. The intensity was 0.5 pN for 7 mu m polystyrene spheres.

    DOI

  • Unified Description of Second-Order Phenomena in Sound Waves

    Tomoo Kamakura, Kenji Yasuda, Yoshiro Kumamoto

    Electronics and Communications in Japan, Part III: Fundamental Electronic Science (English translation of Denshi Tsushin Gakkai Ronbunshi)   82 ( 2 ) 76 - 82  1999.02

    　View Summary

    The generation mechanism of acoustic streaming and radiation pressure are discussed along with the KZK equation, which explains successfully the propagation of finite-amplitude sound waves. The energy loss of a sound beam in a viscous fluid generates the driving force of streaming which induces mass flow in the beam. The radiation pressure acts on the surface of an object whose acoustic impedance is different from the fluid. The effect of flow generated around the object on the radiation pressure is greater when the object is smaller. The main purpose of this paper is to describe the unified relationships among waveform distortion, acoustic streaming, and radiation pressure. © 1998 Scripta Technica.

    DOI

  • Structural information from the interference effect of electron-capture X-rays

    Y. C. Sasaki, K. Yasuda, M. Takahashi, I. Satoh, S. Ishiwata

    Journal of Radioanalytical and Nuclear Chemistry   239 ( 2 ) 341 - 344  1999

    　View Summary

    We observed the interference effect of electron-capture X-rays emitted by the nuclear transformations in radioisotopes. This interference is between the direct monochromatic emission from the radioactive atoms and the emission totally reflected by the substrate surface. Nanometer-level structural information about the radioactive atoms can be obtained by analyzing the measured interference fringes because the period of these fringes depends on the position of the radioactive atoms relative to the substrate surface. In this work, we used the functional protein molecules (myosin subfragment 1(S1)) which were radioiodinated with no carrier added 125I to observe the conformational changes in aqueous solutions.

    DOI

  • Vectorially oriented fixation of membrane-embedded bacteriorhodopsin onto an inert base

    Yoshinori Harada, Kenji Yasuda, Sayuri Nomura, Naoko Kajimura, Yuji C. Sasaki

    Langmuir   14 ( 7 ) 1829 - 1835  1998.02

    　View Summary

    This paper describes a novel surface processing technique aimed at the chemical fixation of proteins on substrate surfaces. The essential feature of this newly developed technique is a combination of chemical and enzymatic processes. A simple technique using chemical modification and selective enzymatic digestion for immobilizing biomembrane-embedded proteins on inorganic solid bases, while strictly regulating their vectorial orientation, was developed. These processes are applicable to a wide range of membrane-embedded and individual proteins, because they exploit the most fundamental principle of proteins, that any protein has at least one N-terminus and one C-terminus. After thorough protection of the carboxyl and amino groups on the molecular surface of bacteriorhodopsin (bR) embedded in purple membrane (PM), in which the bR molecules are uniformly oriented, the derivatized bR was subjected to successive enzymatic digestions to regenerate the unique N-terminal amino group on the molecular surface. The derivatized bR was anchored on an inorganic base by the regenerated amino groups and formed an oriented layered structure. This was proved by analyzing the distance from the base to the gold clusters marking the enzymatically exposed C-termini, which was 4.4 nm, as measured by the fluorescent X-ray interference pattern. This thickness coincides well with that of native PM with embedded bR (4 nm). From the viewpoint of its simplicity, this immobilization process might have an advantage over the former multistep processes for surface functionalization and those for the regulation of the molecular orientation of proteins.

    DOI

  • Acoustic radiation force on micrometer-size particles

    K Yasuda, T Kamakura

    APPLIED PHYSICS LETTERS   71 ( 13 ) 1771 - 1773  1997.09  [Refereed]

    　View Summary

    The acoustic radiation force on micrometer-sized polystyrene spheres was measured through observation of the sphere movement in a 500 kHz ultrasonic standing wave. The known spatial distribution of the force allowed verification of the correlation between the sphere velocity and the force. It was found that the linear dependency of the force on the cube of the sphere radius, as predicted by Yosioka, began to fail when the sphere radius was below 5 mu m. This can be accounted for by the presence of a shell layer surrounding the sphere, which increased the effective radius of the sphere. This may point to applications of the acoustic radiation force in the handling of moicrospheres smaller than hitherto thought possible. (C) 1997 American Institute of Physics.

    DOI

  • Interhead distances in myosin attached to F-actin estimated by fluorescence energy transfer spectroscopy

    S Ishiwata, M Miki, Shin, I, T Funatsu, K Yasuda, CG dosRemedios

    BIOPHYSICAL JOURNAL   73 ( 2 ) 895 - 904  1997.08  [Refereed]

    　View Summary

    Fluorescence resonance energy transfer (FRET) spectroscopy has been used to determine distances between probes attached to the most reactive sulfhydryl (SH1) group on individual myosin ''heads.'' We measured intramolecular and intermolecular interhead distances as well as the distance between one head of heavy meromyosin (HMM) mixed with subfragment-1 (S1) heads attached to F-actin under rigor conditions. The SH1 cysteine was specifically labeled with either a donor (5-((((2-iodoacetyl)amino)ethyl)amino)naphthalene-1-sulfonic acid) or an acceptor probe (5-iodoacetamidofluorescein). In free solution, the distance between these probes was too large to allow significant FRET, but in the rigor complex with F-actin, intermolecular interhead distances between S1 molecules, HMM molecules, or S1 and HMM were determined to be 6.0-6.3 nm, The radial coordinate of the labels relative to F-actin was 5.0-6.4 nm. However, the intramolecular interhead distance in HMMs in which the two heads were labeled with D and A probes was estimated to be larger. The binding affinity of the second head of HMM(D/A) to F-actin may be reduced because of heterogeneous modification of the SH1 groups, such that the probability of single-head binding is increased.

    DOI PubMed

  • Using acoustic radiation force as a concentration method for erythrocytes

    K Yasuda, SS Haupt, S Umemura, T Yagi, M Nishida, Y Shibata

    JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA   102 ( 1 ) 642 - 645  1997.07  [Refereed]

    　View Summary

    We investigated the potential damage inflicted on erythrocytes by acoustic radiation force when the cells are concentrated by a 500-kHz ultrasonic standing wave at the pressure node, The extent of the damage was estimated from the concentrations of potassium ions, iron complexes, and lactate dehydrogenase released from the cells, After 2 min of ultrasound irradiation at 12.8 mJ/m(3), the cells concentrated on the pressure node, with a cell distribution half-width of 138 mu m: no significant release of intracellular components was detected, even after 15 min of irradiation, The results indicate that even small ions like potassium are not released as a result of ultrasound irradiation on cell membranes without cavitation, and they demonstrate the potential use of acoustic radiation force for concentrating living cells in biomedical applications. (C) 1997 Acoustical Society of America.

    DOI PubMed

  • Blood concentration by superposition of higher harmonics of ultrasound

    K Yasuda

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   36 ( 5B ) 3130 - 3135  1997.05  [Refereed]

    　View Summary

    A method for concentrating cells in blood using an acoustic radiation force generated by superposition of the higher harmonics on fundamental ultrasound has been investigated. From the theoretical estimation, the efficiency of concentration of blood cells in a chamber based on a rectangular acoustic radiation force slope calculated by integration of the higher harmonics of ultrasound was 17% better than that based on a sine wave, while the peak pressure was reduced to 32% of that in the sine wave case. Concentration of blood cells was also performed experimentally using superposition of higher harmonics on a 500 kHz sine wave. At a 1.2 ml/min fluid flow rate, the blood cells were concentrated on the pressure node within 9 s, with a cell distribution half-width of 348 mu m (i.e., 76% of blood cells concentrated within 23% of the chamber width), which is 5% narrower than that of the sine wave. Though the experimental result was insufficient for the realization of the theoretical estimation because of the incomplete synthesis of the desired waveform, these results suggest the potential usefulness of this superposition method for improving the concentration efficiency with maintenance of the width of the potential slope and reduction of peak pressure.

    DOI

  • Two-dimensional arrangement of a functional protein by cysteine-gold interaction: Enzyme activity and characterization of a protein monolayer on a gold substrate

    YC Sasaki, K Yasuda, Y Suzuki, T Ishibashi, Satoh, I, Y Fujiki, S Ishiwata

    BIOPHYSICAL JOURNAL   72 ( 4 ) 1842 - 1848  1997.04  [Refereed]

    　View Summary

    We have characterized the functional protein, myosin subfragment 1 (S1), attached to a gold substrate by the sulfhydryl groups of cysteine in proteins. The amino groups of the regulatory light chain (RLC) isolated from myosin were labeled with a radioisotope (I-125), and the labeled RLC was incorporated into S1 from which the RLC had been removed. The radiation from I-125 showed that S1 molecules had attached to the gold and, through the interference effect of the monochromatic radiation from I-125, provided information about the position of labeled RLC sites in the S1 monolayer. The interference fringes showed that the RLC was located close to the gold surface and that all of the adsorbed S1 molecules had the same orientation. We confirmed that the motor function of S1 on the gold surface is maintained by observing sliding movement at low ionic strength and by observing the detachment at high ionic strength of fluorescent actin filaments in the presence of ATP. We also found that the adsorbed S1 molecules were not removed from the Au surface by a reducing agent. Thus the Au-S bond is more stable than the S-S bond.

    DOI PubMed

  • Erythrocytes Concentrated Non-destructively by Acoustic Radiationo Force

      96 ( 432 ) 7 - 14  1996.12

  • Structural and functional reconstitution of thin filaments in the contractile apparatus of cardiac muscle

    H Fujita, K Yasuda, S Niitsu, T Funatsu, S Ishiwata

    BIOPHYSICAL JOURNAL   71 ( 5 ) 2307 - 2318  1996.11  [Refereed]

    　View Summary

    The muscle contractile apparatus has a highly ordered liquid crystalline structure. The molecular mechanism underlying the formation of this apparatus remains, however, to be elucidated. Selective removal and reconstitution of the components are useful means of examining this mechanism. In addition, this approach is a powerful technique for examining the structure and function of a specific component of the contractile system. In this study we have achieved the structural and functional reconstitution of thin filaments in the cardiac contractile apparatus. First, all thin filaments other than short fragments at the Z line were removed by treatment with gelsolin. Under these conditions no active tension could be generated. By incorporating exogenous actin into these thin filament-free fibers, actin filaments were reconstituted, and active tension, which was insensitive to Ca2+, was restored. The active tension after the reconstitution of thin filaments reached 135 +/- 64% of the original level. The augmentation of tension was attributable to the elongation of reconstituted filaments. As another possibility for augmented tension generation, we suggest the presence of an inhibitory system that was not reconstituted. In any case, the thin filaments of the cardiac contractile apparatus are considered to be assembled so as not to develop the highest degree of tension. Incorporation of the tropomyosin-troponin complex fully restored Ca2+ sensitivity without affecting maximum tension. The present results indicate that a muscle contractile apparatus with a higher order structure and function can be constructed by the self-assembly of constituent proteins.

    DOI PubMed

  • Site determination of radioactive atoms from the interference effect of electron-capture rays: Structural change of 111In-labelled azobenzene derivative

    Yuji C. Sasaki, Yoshio Suzuki, Kenji Yasuda, Yashushi Tomioka, Tadashi Ishibashi, Isamu Satoh

    Thin Solid Films   284-285   456 - 458  1996.09

    　View Summary

    The structural change of a 111In-labelled azobenzene derivative was examined using the interference effect of electron-capture X-rays emitted by nuclear transformations in radioactive atoms. Interference fringes were generated between the direct monochromatic emission from the radioactive atoms and the emission totally reflected by the substrate surface. The site of a radioactive atom can be determined by analysing the measured interference fringes, because the period of these fringes depends on the position of the radioactive atoms relative to the substrate surface.

    DOI

  • Studies on particle separation by acoustic radiation force and electrostatic force

    K Yasuda, K Takeda, SI Umemura

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   35 ( 5B ) 3295 - 3299  1996.05  [Refereed]

    　View Summary

    A method for separating particles in liquid by exploiting the competition between acoustic radiation force and electrostatic force has been investigated. To elucidate the size and charge dependence of the shift of the particles away from the sound pressure node, the effective charges of polystyrene spheres and alumina particles, which have opposite signs of electric charge on the surface, were measured for particles of various diameters. The shift of the particles from the pressure node due to the electrostatic force was also measured. Polystyrene spheres smaller than 10 mu m in diameter showed same mobility in a 1 Hz, 13.4V(pp)/mm alternating electric field, which indicates that the effective charge of the particle is directly proportional to the radius of the particle. Using 500 kHz ultrasound and a 0.5 V/mm electric field, 7 mu m polystyrene spheres and 10 mu m alumina particles were shifted in opposite directions, according to the sign of the effective charge on the particles.

    DOI

  • Synchronous behavior of spontaneous oscillations of sarcomeres in skeletal myofibrils under isotonic conditions

    K Yasuda, Y Shindo, S Ishiwata

    BIOPHYSICAL JOURNAL   70 ( 4 ) 1823 - 1829  1996.04  [Refereed]

    　View Summary

    An isotonic control system for studying dynamic properties of single myofibrils was developed to evaluate the change of sarcomere lengths iii glycerinated skeletal myofibrils under conditions of spontaneous oscillatory contraction (SPOC) in the presence of inorganic phosphate and a high ADP-to-ATP ratio, Sarcomere length oscillated spontaneously with a beak-to-peak amplitude of about 0.5 mu m under isotonic conditions in which the external loads were maintained constant at values between 1.5 x 10(4) and 3.5 x 10(4) N/m(2). The shortening and yielding of sarcomeres occurred in concert, in contrast to the previously reported conditions (isometric or auxotonic) under which the myofibrillar tension is allowed to oscillate, This synchronous SPOC appears to be at a higher level of synchrony than in the organized state of SPOC previously observed under auxotonic conditions, The period of sarcomere length oscillation did not largely depend on external load. The active tension under SPOC conditions increased as the sarcomere length increased fi-om 2.1 to 3.2 mu m, although it was still smaller than the tension under normal Ca2+ contraction (which is on the order of 10(5) N/m(2)). The synchronous SPOC implies that there is a mechanism fbr transmitting information between sarcomeres such that the state of activation of sarcomeres is affected by the state of adjacent sarcomeres. We conclude that the change of myofibrillar tension is not responsible for the SPOC of each sarcomere but that it affects the level of synchrony of sarcomere oscillations.

    DOI PubMed

  • Particle separation using acoustic radiation force and electrostatic force

    K Yasuda, S Umemura, K Takeda

    JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA   99 ( 4 ) 1965 - 1970  1996.04  [Refereed]

    　View Summary

    A method for separating particles in liquid by exploiting the competition between acoustic radiation force and electrostatic force is investigated. The displacement of particles from the pressure node of an ultrasound standing wave varies according to the effective charges, radii, and stiffness of the particles, and the particles of different radii can thus be separated even when they consist of the same material. When the particles are of different materials, they can also be separated in relations to their effective electric charges or their stiffness. In this study, the efficacy of this method was theoretically estimated and demonstrated by an experiment, with a mixture of polystyrene spheres of different radii in water, using 500-kHz ultrasound and a 3.3-V/mm electric field. The measured ratio of the displacements of polystyrene spheres 10 and 20 mu m in diameter from the pressure node was 2:3, which is consistent with the value predicted theoretically. Radiation forces on the polystyrene spheres were also measured by using this technique. (C) 1996 Acoustical Society of America.

    DOI

  • Deoxyribonucleic acid concentration using acoustic radiation force

    K Yasuda, M Kiyama, S Umemura, K Takeda

    JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA   99 ( 2 ) 1248 - 1251  1996.02  [Refereed]

    　View Summary

    A deoxyribonucleic acid (DNA) concentration method using acoustic radiation force is proposed. Ethanol was added to an aqueous DNA sample in order to initiate clustering of the DNA molecules of 2686 bps. The change in the distribution of the DNA clusters induced by a standing wave ultrasound irradiation was observed with an optical microscope. The observable DNA clusters gathered on the pressure node in the ultrasonic standing wave field and formed larger clusters that did not break apart after the irradiation was stopped. Without ultrasound irradiation, no significant change in the cluster distribution was observed. This method may have a potential use for concentrating and collecting biomaterials such as nucleic acids and proteins. (C) 1996 Acoustical Society of America.

    DOI

  • Microscopic analysis of the elastic properties of connectin/titin and nebulin in myofibrils

    S Ishiwata, K Yasuda, Y Shindo, H Fujita

    ADVANCES IN BIOPHYSICS, VOL. 33, 1996   33   135 - 142  1996  [Refereed]

    DOI PubMed

  • Ca2+-induced tension development in the stalks of glycerinated Vorticella convallaria

    Y Moriyama, K Yasuda, S Ishiwata, H Asai

    CELL MOTILITY AND THE CYTOSKELETON   34 ( 4 ) 271 - 278  1996  [Refereed]

    　View Summary

    We have developed a method of measuring the isometric tension in glycerinated stalks of Vorticella convallaria. Using this method, we measured tension vs. pCa relations in glycerinated V. convallaria stalks. The maximum isometric tension was 4 x 10(-8) N on average. The Hill's parameter, n, which is the number of calcium ions bound simultaneously and cooperatively to a contractile element (a force generating element), is approximately 3.2 when the Ca2+ concentration is increased and 2.5 when it is decreased. In order to estimate the efficiency of the energy conversion of Ca2+ binding to mechanical work, we measured the Ca2+ induced Carnot cycle in the Vorticella stalk. The energy efficiency was tentatively estimated to be about 7%. With this method, we have also succeeded in measuring the isometric tension of isolated spasmoneme, the rubber-like contractile fibrous organelle in the stalk. The maximum tension of spasmoneme was approximately one tenth that of the glycerinated stalk. We speculate that the isolated spasmoneme was only partially functional due to damage sustained when it was pulled out Of the stalk. (C) 1996 Wiley-Liss, Inc.

    DOI PubMed

  • CONCENTRATION AND FRACTIONATION OF SMALL PARTICLES IN LIQUID BY ULTRASOUND

    K YASUDA, S UMEMURA, K TAKEDA

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS   34 ( 5B ) 2715 - 2720  1995.05  [Refereed]

    　View Summary

    The efficacy of the ultrasonic standing plane wave in concentrating small particles was theoretically evaluated and compared with experimental results. Acoustic energy density was estimated by measuring the ultrasonic absorption, and particle distribution was observed by dark-field microscopy. The theory predicts that diffusion is negligible in concentrating polystyrene spheres larger than 5 mu m in diameter when they are subjected to 2J/m(3) ultrasound. The half-width of the steady-state particle distribution was of the same order of magnitude as the theoretical value for the particles of 1 mu m and 2 mu m diameter. We also applied this concentrating technique to fractionation of polystyrene spheres 10 mu m in diameter, and more than 90% of the particles in the laminar flow were successfully collected.

    DOI

  • MICROSCOPIC ANALYSIS OF THE ELASTIC PROPERTIES OF NEBULIN IN SKELETAL MYOFIBRILS

    K YASUDA, T ANAZAWA, S ISHIWATA

    BIOPHYSICAL JOURNAL   68 ( 2 ) 598 - 608  1995.02  [Refereed]

    　View Summary

    The elastic properties of nebulin were studied by measuring the elasticity of single skeletal myofibrils, from which the portion of the thin filament located at the I band had been selectively removed by treatment with plasma gelsolin under rigor conditions. In this myofibril model, a portion of each nebulin molecule at the I band was expected to be free of actin filaments and exposed. The length of the exposed portion of the nebulin molecule was controlled by performing the gelsolin treatment at various sarcomere lengths. The relation between the passive tension and extension of the exposed portion of the nebulin showed a convex curve starting from a slack length, apparently in a fashion similar to that of wool. The slack sarcomere length shifted depending on the length of the exposed portion of the nebulin, however, the relation being represented by a single master curve. The elastic modulus of nebulin was estimated to be two to three orders of magnitude smaller than that of an actin filament. Based on these results, we conclude that nebulin attaches to an actin filament in a side-by-side fashion and that it does not significantly contribute to the elastic modulus of thin filaments. The relation between the passive tension and extension of connectin (titin) was obtained for a myofibril from which thin filaments had been completely removed with gelsolin under contracting conditions; this showed a concave curve, consistent with the previous results obtained in single fibers.

    DOI PubMed

  • 31. Length Regulation of Thin Filaments without Nebulin

    Kenji Yasuda, Hideaki Fujita, Yasutake Fujiki, Shinichi Ishiwata

    Proceedings of the Japan Academy, Series B   70 ( 9 ) 151 - 156  1994

    　View Summary

    : Recent work has suggested that the length of thin filaments in skeletal muscles is determined by a protein ruler, nebulin, located along the long axis of thin filaments. To examine the function of nebulin, the length distribution of the thin filaments was investigated by staining actin filaments with fluorescent rhodamine-phalloidin in rabbit cardiac muscles, which do not contain nebulin, and in skeletal muscles, which contain nebulin, by laser scanning confocal microscopy. The microscopic observation showed a difference in staining patterns between cardiac and skeletal muscle fibers when the staining was done without chemical fixation. This suggests that nebulin suppresses the attachment of phalloidin to actin filaments. Analysis of fluorescence distribution showed that the length deviation of thin filaments in the cardiac muscle was as small as that in the skeletal muscle. This indicates that the length of the thin filaments is regulated even without nebulin. © 1994, The Japan Academy. All rights reserved.

    DOI

  • Mechano-chemical coupling in spontaneous oscillatory contraction of muscle

    Shin'ichi Ishiwata, Kenji Yasuda

    Phase Transitions   45 ( 2-3 ) 105 - 136  1993.11

    DOI

  • SPONTANEOUS TENSION OSCILLATION (SPOC) OF MUSCLE-FIBERS AND MYOFIBRILS MINIMUM REQUIREMENTS FOR SPOC

    S ISHIWATA, T ANAZAWA, T FUJITA, N FUKUDA, H SHIMIZU, K YASUDA

    MECHANISM OF MYOFILAMENT SLIDING IN MUSCLE CONTRACTION   332   545 - 554  1993  [Refereed]

    DOI PubMed

  • SPONTANEOUS OSCILLATION OF TENSION AND SARCOMERE-LENGTH IN SKELETAL MYOFIBRILS - MICROSCOPIC MEASUREMENT AND ANALYSIS

    T ANAZAWA, K YASUDA, S ISHIWATA

    BIOPHYSICAL JOURNAL   61 ( 5 ) 1099 - 1108  1992.05  [Refereed]

    　View Summary

    We have devised a simple method for measuring tension development of single myofibrils by micromanipulation with a pair of glass micro-needles. The tension was estimated from the deflection of a flexible needle under an inverted phase-contrast microscope equipped with an image processor, so that the tension development is always accompanied by the shortening of the myofibril (auxotonic condition) in the present setup. The advantage of this method is that the measurement of tension (1/30 s for time resolution and about 0.05-mu-g for accuracy of tension measurement; 0.05-mu-m as a spatial resolution for displacement of the micro-needle) and the observation of sarcomere structure are possible at the same time, and the technique to hold myofibrils, even single myofibrils, is very simple. This method has been applied to study the tension development of glycerinated skeletal myofibrils under the condition where spontaneous oscillation of sarcomeres is induced, i.e., the coexistence of MgATP, MgADP and inorganic phosphate without free Ca2+. Under this condition, we found that the tension of myofibrils spontaneously oscillates accompanied by the oscillation of sarcomere length with a main period of a few seconds; the period was lengthened and shortened with stretch and release of myofibrils. A possible mechanism of the oscillation is discussed.

    DOI PubMed

  • Spontaneous oscillatory contraction (SPOC) of sarcomeres in skeletal muscle

    Shin'Ichi Ishiwata, Nobuyuki Okamura, Hideharu Shimizu, Takashi Anazawa, Kenji Yasuda

    Advances in Biophysics   27 ( C ) 227 - 235  1991

    DOI PubMed

▼display all

Books and Other Publications

  • Biomedical Photonics Handbook

    Kenji Yasuda( Part： Joint author)

    CRC Press  2014.07

  • 創薬研究ツール

    安田賢二( Part： Joint author)

    メディカルドゥ  2014.02 ISBN: 9784944157716

  • 再生医療製品の許認可と組織工学の新しい試み（監修 岩田博夫、松岡厚子、岸田晶夫）

    安田賢二( Part： Joint author)

    シーエムシー出版  2012.05 ISBN: 9784781305837

  • ものづくり技術からみる再生医療-細胞研究・創薬・治療-（監修 田畑泰彦）

    安田賢二( Part： Joint author)

    シーエムシー出版  2011.11 ISBN: 9784781304724

  • High Resolution Microbial Single Cell Analytics (Editer: Müller, Susann; Bley, Thomas)

    Yasuda K( Part： Joint author)

    Springer  2010.11 ISBN: 9783642168864

  • バイオチップ実用化ハンドブック

    安田賢二( Part： Joint author)

    株式会社エヌ・ティー・エス  2010.04 ISBN: 9784860432706

  • ヘルスケアとバイオ医療のための先端デバイス機器

    安田賢二( Part： Joint author)

    シーエムシー出版  2009.05 ISBN: 9784781301204

  • マイクロ・ナノ化学チップと医療・環境・バイオ分析（監修 北森武彦）

    安田賢二( Part： Joint author)

    技術教育出版  2009.01 ISBN: 9784907837174

  • 次世代医療のための高分子材料工学（監修 秋吉一成、岸田晶夫）

    安田賢二( Part： Joint author)

    シーエムシー出版  2008.09 ISBN: 9784781300559

  • Encyclopedia of Microfluidics and Nanofluidics (Editer: Li, Dongqing ）

    Kenji Yasuda( Part： Joint author)

    Springer  2008.07

  • 細胞分離・操作技術の最前線（監修 福田敏男、新井史人）

    安田賢二( Part： Joint author)

    シーエムシー出版  2008.04 ISBN: 9784781300047

  • 非侵襲・可視化ハンドブック（小川誠二、上野照剛 監修）

    安田賢二( Part： Joint author)

    エヌ・ティーエス  2007.06 ISBN: 9784860431334

  • 生命システムをどう理解するか（浅島誠 編集）

    安田賢二( Part： Joint author)

    共立出版  2007.05 ISBN: 9784320056480

  • 高校生のための東大授業ライブ（東京大学教養学部 編）

    安田賢二( Part： Joint author)

    東京大学出版会  2007.03 ISBN: 9784130004503

  • バイオプロセスハンドブック

    安田賢二( Part： Joint author)

    エヌ・ティー・エス  2007.03

  • ナノバイオ大事典（山根恒夫、松永是、民谷栄一 監修）

    安田賢二( Part： Joint author)

    テクノシステム  2007.01

  • Frontiers in Life Sciences (Editer: Fujiwara M, Sato N & Ishiura S)

    Yasuda K( Part： Joint author)

    Research Signpost  2006.07 ISBN: 8130800713

  • ナノバイオ－微細加工と計測技術の新展開（（社）高分子学会 編）

    安田賢二( Part： Joint author)

    株式会社エヌ・ティー・エス  2005.10 ISBN: 9784860430948

  • レーザーハンドブック第2版（レーザー学会 編）

    安田賢二( Part： Joint author)

    オーム社  2005.04 ISBN: 9784274200359

  • バイオチップの最新技術と応用（監修 松永 是）

    安田賢二( Part： Joint author)

    シーエムシー出版  2004.06 ISBN: 9784781301549

  • Lab-on-Chips for Cellomics (Editer: Helene Andersson and Albert van den Berg)

    Yasuda K( Part： Joint author)

    Kluwer Academic Publishers, Netherlands.  2004 ISBN: 9781402028601

  • ナノテクノロジーハンドブック Ⅳ編（ナノテクノロジーハンドブック編集委員会 編）

    安田賢二( Part： Joint author)

    オーム社  2003.05

  • Biomedical Photonics Handbook (Editer: Tuan Vo-Dinh)

    Yasuda K( Part： Joint author)

    CRC Press  2003.03 ISBN: 9780849311161

  • マイクロマシン技術総覧（監修 樋口俊郎）

    安田賢二( Part： Joint author)

    産業技術サービスセンター  2003.01 ISBN: 9784915957406

  • －異種要素を集積化した小形で高度な働きをするシステム－ マイクロマシン（監修 江刺正喜）

    安田賢二( Part： Joint author)

    産業技術サービスセンター  2002.02 ISBN: 9784915957383

▼display all

Misc

  • On-Chip Cellomics Technology: Soft Nanotechnology for Constructive Cell Network Research for Life Science, Drug Discovery, and Medical Diagnostics

    YASUDA Kenji, NOMURA Fumimasa, TERAZONO Hideyuki, KIM Hyonchol, HATTORI Akihiro

    J. Surf. Sci. Soc. Jpn.   37 ( 5 ) 213 - 217  2016

    　View Summary

    Technologies of analyzing epigenetic information have been developed starting from the twin complementary viewpoints of cell regulation as an &amp;lsquo;algebraic&amp;rsquo; system (emphasis on temporal aspects) and as a &amp;lsquo;geometric&amp;rsquo; system (emphasis on spatial aspects). Exploiting the combination of latest microfabrication technologies and measurement technologies, which we call &amp;lsquo;on-chip cellomics technology&amp;rsquo;, we can control and re-construct the interaction of cell-networks from &amp;lsquo;algebraic&amp;rsquo; and &amp;lsquo;geometric&amp;rsquo; viewpoints. In this review, our developed technologies and some results for spatial viewpoint of epigenetic information as a part of a series of cell-network-based &amp;lsquo;geometric&amp;rsquo; studies of celluler systems in our research groups are summerized and reported. The knowlege and technologies acquired from these viewpoints may lead to the use of cells that fully control practical applications like cell network-based drug screening and the regeneration of organs from cells.

    DOI CiNii

  • 超常磁性カップによるサイズ選択的細胞回収

    金 賢徹, 寺薗 英之, 野村 典正, 安田 賢二

    生体材料工学研究所年報   48   30 - 35  2015.03

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 カップ形状超常磁性微粒子“magcup”を用いたサイズ選択的細胞精製技術の開発

    KIM H., 寺薗英之, 竹井弘之, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成26年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2015

    J-GLOBAL

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 超音波放射圧による生体微粒子ハンドリング

    松浦賢志, 野村典正, KIM H., 寺薗英之, 服部明弘, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成26年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2015

    J-GLOBAL

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 血液中の単一がん細胞を認識するためのイメージングバイオマーカーの評価

    尾高正朗, KIM H., MATHIAS Girault, 服部明弘, 松浦賢志, 寺薗英之, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成26年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2015

    J-GLOBAL

  • On-Chip Quasi-in vivo Predictive Cardiotoxicity Assay using Spatiotemporal Fluctuation Measurement on Human Cardiomyocyte Cell-Network

    Fumimasa Nomura, Tomoyuki Kaneko, Hideyuki Terazono, Kenji Yasuda

    BIOPHYSICAL JOURNAL   108 ( 2 ) 111A - 111A  2015.01

    Research paper, summary (international conference)  

    DOI

  • Development of a method to identify circulating tumor cells using a on-chip imaging cell sorting system

    寺薗 英之, 金 賢徹, 尾高 正朗, Girault Mathias, 野村 典正, 服部 明弘, 安田 賢二

    生体材料工学研究所年報   49   33 - 37  2015

    CiNii J-GLOBAL

  • Toward quasi-in vivo from in vitro assay (I): Development of spatial conductance fluctuation measurement assay using a human cardiomyocyte line-network cell chip with multielectrode array system for in vitro predictive proarrhythmic cardiotoxicity

    Tomoyo Hamada, Fumimasa Nomura, Hideyuki Terazono, Akihiro Hattori, Peter Sartipy, Mitsuhiro Edamura, Thomas Meyer, Kenji Yasuda

    JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS   70 ( 3 ) 320 - 320  2014.11

    Research paper, summary (international conference)  

    DOI

  • Toward quasi-in vivo from in vitro assay (II): Importance of spatial arrangement of cardiomyocyte network for precise and stable in vitro drug screening measurement

    Fumimasa Nomura, Tomoyo Hamada, Hideyuki Terazono, Kenji Yasuda

    JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS   70 ( 3 ) 319 - 320  2014.11

    Research paper, summary (international conference)  

    DOI

  • 【微細加工技術とバイオマテリアル】 オンチップセロミクスと微細加工技術

    安田 賢二, 野村 典正, 寺薗 英之, 金 賢徹, 服部 明弘

    バイオマテリアル-生体材料-   32 ( 4 ) 308 - 323  2014.10

    　View Summary

    生命システムを総合的に理解するため、ゲノム情報と相補的な情報である細胞と細胞集団(ネットワーク)が持つ後天的情報の解明のために開発してきた一連の技術手法および装置システムを開発している。&quot;細胞&quot;は、後天的情報を保持できる最小単位であり、いままでの遺伝子情報の解明のみでは説明ができないさまざまな生化学反応の履歴を後天的情報として保持している。遺伝情報を補完する細胞の後天的情報の役割は、遺伝情報のみからでは得られない順応や集団効果プロセスを比較理解することで明らかにすることができるのである。後天的情報を理解するためのシステムの開発は、&quot;時間的発展(順序)&quot;&quot;空間的配置&quot;という二つの観点で生命システムを理解するための&quot;細胞&quot;制御技術として開発を進めてきた。最新の微細加工技術と計測技術を組み合わせた系(筆者らはこれをオンチップセロミクス系とよんでいる)を用い、これら二つの観点から細胞やその相互作用、環境を制御し、再構成することが可能となっている。この解説では、特に後天的情報の&quot;空間的&quot;観点から開発した一連の技術をまとめ紹介している。この研究から得られた知見は、細胞を、創薬毒性検査や再生医療などのより具体的な応用への実現を可能にするものと考えている。(著者抄録)

  • ヒトiPS/ES等幹細胞から分化した心筋細胞を用いた不整脈予測法の開発

    野村 典正, 浜田 智代, 寺薗 英之, 金 賢徹, 服部 明弘, 安田 賢二

    生体材料工学研究所年報   47   26 - 29  2014.03

  • 超常磁性カップの作製とサイズ選択的細胞回収

    KIM Hyonchol, 寺薗英之, 寺薗英之, 竹井弘之, 竹井弘之, 安田賢二, 安田賢二

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)   75th  2014

    J-GLOBAL

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 液体循環型高速遺伝子増幅装置の温度安定性の検討と循環水の原理を用いた融解曲線分析法の開発

    寺薗英之, 松浦賢志, KIM H., 服部明弘, 竹井弘之, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成25年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2014

    J-GLOBAL

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 明視野・蛍光デュアルイメージングによる「細胞形状」情報からの細胞識別技術の開発

    服部明弘, MATHIAS Girault, 尾高正朗, KIM H., 寺薗英之, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成25年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2014

    J-GLOBAL

  • 地域イノベーション戦略支援プログラム 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成-がんや生活習慣病の診断・創薬・治療に寄与する計測・評価システム がん治療・創薬支援のための全自動CTC解析システムの実用化 1細胞レベルでの分離計測技術の高度化 カップ状微細構造を用いたサイズ依存的細胞精製技術の開発

    KIM H., 寺薗英之, 竹井弘之, 安田賢二

    神奈川国際ライフサイエンス実用化拠点 平成25年度報告書 革新的計測・評価技術によるライフイノベーション創生-レギュラトリーサイエンス推進拠点の形成    2014

    J-GLOBAL

  • がん克服戦略における皮膚科学の可能性を追求する Circulating Tumor Cellの検出と分離、画像型セルソーターのテクノロジー

    安田 賢二, 金 賢徹, 寺園 英之, 荒尾 徳三, 大津 敬, 中村 圭靖, 宮城 洋平, 西尾 和人

    西日本皮膚科   75 ( 3 ) 248 - 249  2013.06

  • 超音波放射圧による生体微粒子ハンドリング

    安田 賢二, 金子 智行, 野村 典正, 浜田 智代, 金 賢徹, 寺薗 英之, 服部 明弘

    生体材料工学研究所年報   46   20 - 23  2013.03

  • バイオマーカーによるがん個別化治療 血中がん細胞解析を目指したオンチップ・イメージングフローサイトメトリー技術の開発(Personalized cancer medicine and biomarker Development of on-chip imaging flow cytometry technology for circulating tumor cell analysis)

    安田 賢二, 金 賢徹, 寺薗 英之, 荒尾 徳三, 大津 敬, 中村 圭靖, 宮城 洋平, 西尾 和人

    日本癌学会総会記事   71回   413 - 413  2012.08

  • Development of Adaptive SEM Technology for in situ Molecular Expression Analysis in Single Cell Level Using Nano-Particle Probe Array Consisting of Various Elements

    KIM Hyonchol, TERAZONO Hideyuki, TAKEI Hiroyuki, YASUDA Kenji

    顕微鏡 = Microscopy   47 ( 1 ) 59 - 64  2012.03

    CiNii

  • 液体循環型超高速PCR装置の開発

    寺薗 英之, 服部 明弘, 金 賢徹, 安田 賢二

    生体材料工学研究所年報   45   31 - 34  2012.03

  • Present state and prospects of measurement technologies for analysis of circulating tumor cell

    HAYASHI Masahito, KIM Hyonchol, TERAZONO Hideyuki, HATTORI Akihiro, YASUDA Kenji, OHTSU Takashi, MIYAGI Yohei, ARAO Tokuzo, NISHIO Kazuto

      21 ( 2 ) 1 - 6  2011.10

    DOI CiNii

  • 一細胞ゲノム・プロテオーム解析システムの要素技術開発

    金 賢徹, 寺薗 英之, 林 真人, 竹井 弘之, 安田 賢二

    生体材料工学研究所年報   44   33 - 36  2011.03

  • Quantitative in situ Measurement of Target Biomolecules by Metal Nano-Particle Label Sets and "Adaptive SEM" Technology

    H. Kim, H. Terazono, M. Hayashi, H. Takei, K. Yasuda

    MOLECULAR BIOLOGY OF THE CELL   22  2011

    Research paper, summary (international conference)  

  • サイトメトリーシステムの未来を考える CTC技術の最前線・がん転移計測技術と医療応用 CTC計測装置技術の現状と次世代CTC装置技術の展望

    林 真人, 寺薗 英之, 金 賢徹, 関島 勝, 宮城 洋平, 安田 賢二

    Cytometry Research   20 ( Suppl. ) 45 - 45  2010.06

  • On-chip cellomics technology for drug screening system using cardiomyocyte cells from human stem cell

    Kenji Yasuda

    Yakugaku Zasshi   130 ( 4 ) 545 - 557  2010.04

    Book review, literature introduction, etc.  

    　View Summary

    Limitation of conventional human Ether-a-go-go Related Gene (hERG) assay and QT prolongation testing for accurate prediction of Torsades de Pointes (TdP) by compounds showed us the necessity of a new approach to evaluate global cardiac safety. As one of the advanced applications of an on-chip cellomics system, on-chip cardiomyocyte cell network-based re-entry model assay has the potential to measure the TdP probability as a pre-clinical test for cardiac safety. This system also can estimate the heart pressure, Na, K, and Ca ion channel conditions using a single cell-based optical/electrical measurement system. In this presentation, we present the system setup and then its possible application for drug discovery and toxicology. © 2010 The Pharmaceutical Society of Japan.

    DOI

  • Nano-Bio Technology for Pharmaceutical Science : Advances of On-Chip Technology to Drug Screening System Using Cardiomyocyte Cells from Human Stem Cell

    YASUDA Kenji

      70 ( 1 ) 45 - 50  2010.01

    CiNii

  • 2P322 Evaluation of a polyurea thin film by vapor deposition polymerization as the surface for uniform probe immobilization

    Kira A, Kim H, Okano K, Yasuda K

    Seibutsu Butsuri   45 ( 0 )  2005

    CiNii

  • 2P323 Quantitative Analysis of Expressed Rare Messages in Single Cell Level using Gold Nano-Particles

    Kim H, Kira A, Kohno H, Matsumura K, Orita K, Oikawa K, Okano K, Yasuda K

    Seibutsu Butsuri   45 ( 0 )  2005

    CiNii

  • 2P324 Method and its evaluation of SH-ssDNA modification onto gold nanoparticle

    Kohno H, Kira A, Kim H, Okano K, Yasuda K

    Seibutsu Butsuri   45 ( 0 )  2005

    CiNii

  • On-chip single-cell based analysis system for cellomics study

    Kenji Yasuda

    Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme   49 ( 11 Suppl ) 1917 - 1923  2004.08

    Book review, literature introduction, etc.  

    PubMed

  • 3P304 Improvement of method for time-lapse measurement of mRNA in single live cell

    Kohno H, Kim H, Suzuki I, Okano K, Osada T, Ikai A, Yasuda K

    Seibutsu Butsuri   44 ( 0 )  2004

    CiNii

  • 3P305 Development of Probe Production for Quantitative Measurement of Expressed Gene Numbers

    Kim H, Okano K, Yasuda K

    Seibutsu Butsuri   44 ( 0 )  2004

    CiNii

  • Separation and purification of single cells using on -chip cell sorter

    YASUDA Kenji

    Journal of Japanese Society for Biomaterials   21 ( 2 ) 127 - 132  2003.03

    CiNii

  • 3I0945 Development of on chip cell sorter with phase contrast/fluorescence microscopic image processing

    Takahashi K, Hattori A, Ichiki T, Yasuda K

    Biophysics   42 ( 2 )  2002.10

    CiNii

  • 24pYC-7 A control with mechanical stimulus of spontaneous oscillation of skeletal muscle

    Shimamoto Y., Suzuki M., Yasuda K., Ishiwata K.

    Meeting abstracts of the Physical Society of Japan   57 ( 1 ) 312 - 312  2002.03

    CiNii

  • 超音波輻射圧による生体微粒子操作技術(共著)

    安田 賢二, 八木 俊樹

    生物物理   39 ( 3 ) 176 - 178  1999

    DOI CiNii

▼display all

Industrial Property Rights

▼display all

Awards

  • 平成28年度特別研究員等審査会専門委員（書面担当）及び国際事業委員会書面審査員 表彰

    2017.10   独立行政法人 日本学術振興会  

  • 平成25年度「科研費」有意義な審査意見を付した審査委員 表彰

    2013.10   独立行政法人 日本学術振興会  

  • 日本サイトメトリー学会学術奨励賞 平成23年度Cytometry Research最優秀論文

    2012.06   日本サイトメトリー学会   CTC計測装置技術の現状と次世代 CTC装置 技術の展望

    Winner： Masahito Hayashi, Hyonchol Kim, Hideyuki Terazono, Akihiko Hattori, Kenji Yasuda, Takashi Ohtsu, Yohei Miyagi, Tokuzo Arao, Kazuto Nishio

  • MNC 2009 Outstanding Paper Award

    2010.11   応用物理学会   Non-amplified quantitative detection of nucleic acid sequences using a gold nanoparticle probe set and field emission scanning electron microscopy

    Winner： Hyonchol Kim, Atsushi Kira, Kenji Yasuda

  • MNC 2004 Award for Most Impressive Presentation

    2005.10   応用物理学会   Single-Cell-Based Electrophysiological Measurement of a Topographically Controlle Neuronal Network Using Agarose Architecture with a Multi-Electrode Array

    Winner： Ikuro Suzuki, Yoshihiro Sugio, Yasuhiko Jimbo, Kenji Yasuda

  • 応用物理学会論文賞

    2000.10   応用物理学会   Measurement of Microscopic Spatial Distribution of Acoustic Radiation Force Using Microspheres and Electrostatic Force

    Winner： 安田賢二

▼display all

Research Projects

  • 血中がん細胞を無染色識別する「イメージング・バイオマーカー」解析技術の開発

    Project Year :

    2017.04
    -
    2022.03
     

    　View Summary

    初年度に引き続き要素技術の開発を推進した。「細胞塊」をマイクロ流路系で用いる場合１細胞から巨大な細胞塊までのサイズの異なるターゲットを同時に流す事ができる流路系を用いるため、被写界深度の幅を増大させて像ぼけが起きにくい観察光学系を構築する必要があるが、ズームレンズ系と開口数の小さな対物レンズに画像処理技術を組み合わせることで必要な細胞集団の形状、細胞核の形状を同定することができるアナログ＋デジタル画像処理技術を最適化することに成功した。次に、明視野像と蛍光像を同時に取得し、これをカメラの１つの受光素子で同時取得・解析するため、すでに開発・設計してきた複数の単色光明視野同時取得／比較計測技術に、新たにFPGA技術と高速デジタルカメラを組み合わせ毎秒５０００個以上の細胞を実時間判別する技術の原理検討を進めた。FPGA技術には市販のNI社FPGAを組み込みフィードバック制御で細胞の流路中での流速を実時間で検出することを可能にした。さらに細胞の分離精製技術として、アルギン酸によって細胞を包むことによって細胞ごとに異なる細胞電荷に関係なく、表面のアルギン酸カプセルの電荷で安定に細胞を分取する技術の原理検討に成功した（特許出願手続き中）。またハードウエア技術の開発に並行して「細胞塊」「核状態」などの画像高速同定アルゴリズムの開発を推進し、転移がんモデル動物の血液試料を用いて「３細胞以上のクラスター」を輪郭あるいは内部の核の分布、形状などから総合的に解明、判断する技術を開発した。明視野像で得られる細胞の輪郭を画面全体で判別するのではなく、局所ごとにしきい値設定を重ね合わせて正確な「細胞（塊）」の形状を数値化する新規のアルゴリズムであり（特許出願手続き中）、従来の手法では比較解析できなかった細胞クラスター数の転移がん移植後の増加傾向や多核細胞の増加などを詳細に報告する論文の報告ができた。２年前に東京医科歯科大学から早稲田大学に転出し研究室立ち上げとあわせて研究テーマ立ち上げを行ったため、装置類のセットアップなどに時間がかかってしまったが、２０１８年３月（２０１７年度末）には、研究室内にクリーンルームも立ち上げあることができ、チップ開発を含めたマイクロ加工技術も含めた装置システムの全体的な開発が開始できるようになった。また、動物実験施設の許可も受け、今まで血中の転移がんの状態の日変化をトレースした論文はなかったが、２０１８年度に初めてこれを論文として公開することができた。また、装置開発も順調に進んでおり、特許出願を進めることができた。これによって２０１８年度は「（１）計画以上に進展している」と判断させていただいた。これまでの試作成果を踏まえ、「細胞塊」をより効率的に分析するため、新たに、粒径の違いによって連続して自動的に選別するプレ選別機構を持った微細流路を前処理として付加して、細胞塊のみに特化した計測をする計測系に改善する。この細胞塊のみが流れてくる状況での被写界深度の幅を増大させて像ぼけが起きにくい観察光学系を構築し、ズームレンズ系と開口数の小さな対物レンズ、そして画像処理技術を最適化して細胞集団の形状、細胞核の形状を同定できるアナログ＋デジタル画像処理技術を完成させる。また高い時間処理能力を持った細胞形状識別技術の開発として、特に蛍光光源の入射法を工夫して、今年度成功したFPGA技術と高速デジタルカメラを組み合わせた明視野像と蛍光像の１受光素子で同時取得・解析技術の改良開発を行う。さらに細胞の分離精製技術として、アルギン酸カプセルに細胞を含ませて、アルギン酸カプセルの持つ安定した表面電荷を利用して微弱外部静電場のスイッチングで効果的に分離する技術を実用レベルまで改良する。上記、ハードウエア技術の開発に並行して、システムのソフトウエア技術開発である「細胞塊」「核状態」などの高速同定アルゴリズム（「イメージング・バイオマーカー」抽出技術）の開発をアルギン酸カプセル中の細胞判別技術に発展させて推進する。アルギン酸カプセル中の明視野像で得られる細胞の輪郭は、水中と同様に、その輝度に分布があるため既存の自動しきい値による切り出しを行うと周囲形状が欠損する可能性があるため、今年度開発に成功した局所でのしきい値設定を重ね合わせて、正確な「細胞（塊）」の形状の数値化する新規のアルゴリズムを最適化する。また、核の空間分布から、分裂細胞の核形状であるのか、多核細胞であるのか、細胞集団であるのかを識別するアルゴリズムの開発なども引き続き推進する

  • Davelopment of Method to Analyse the Function of Regulatory Proteins in Single by Cells by Gene Handling Technique.

    　View Summary

    Recovery of DNA fragment from a DNA probe array : We have developed a DNA preparation method using a DNA probe array that utilizes photo-thermal denaturation to recover specific DNA. The protocol for preparing DNA probe array was investigated to realize the stable immobilization of DNA probes on the surface of solid support. We used a glass plate coated with Cr (5-10 nm thick). The Cr surface was modified with 3-glysidoxypropyltrimethoxysilane to introduce active residues that can couple with amino residues at the 5' terminal of DNA probes. The Cr surface acts as a photo-thermal transducer. The preparation method of DNA uses infrared (1053-nm) laser irradiation to thermally denature and release DNA immobilized in a specific area of a DNA probe array. Different DNA fragments fixed in place on the DNA probe array could be separately recovered. There were enough quantities of recovered DNA that can be amplified by using PCR. Trial to synthesize caged DNA : Aiming at synthesizing caged DNA, we tried to chemically modify an amino-residue on DNA with 4, 5-diraethoxy-2-nitrobenzyl bromide (DMNBB). Although the synthesis of chemically modified DNA once appeared to be confirmed by using PCR method, we finally reached a conclusion that the amino-residue on DNA is not reactive to the chemical modification. Expression of GFP-actin in cultured embryonic heart cells : We could confirm that GFP-actin was expressed in cultured embryonic heart cells under fluorescence microscopy. Although we may have not be able to achieve the original goal, the results obtained in this project must be, we believe, very useful for planning a future project

  • 細胞内における調節タンパク質機能解析のためのmRNA発現制御技術の検討

    　View Summary

    Caged遺伝子の合成:Caged mRNAを作成するための第一段階として、Caged DNAの調製を試みた。すなわち、DNA塩基のアミノ基を化学修飾(Cage化)することによって複製機能を失活し、紫外光照射によってCageを外して再活性化させることのできる不活性化DNAを合成した。その結果、光照射によって複製機能がある程度再生可能であることを、PCR法を用いて確認した。細胞操作と共焦点顕微鏡観察:心筋細胞培養系での自動拍動現象におけるCaイオンの時空間パターン(Ca wave)を、Ca感受性蛍光色素を細胞内に導入することによってビデオレートで蛍光共焦点顕微観察・記録することができた。この細胞実験系は、Caged遺伝子を導入のために不可欠のものである。遺伝子の固定化と選択回収技術:DNA多成分同時分取法を確立する目的で、近赤外レーザー光を用いてチップ上の局所領域のみを加熱変性し、特定のDNA断片を回収することのできるDNAチップの基本実験を行った。6nmの厚さにクロム蒸着したガラス基板上にDNAプローブを固定し、蛍光ラベルした試料DNAプローブを流して蛍光観察したところ、試料DNAプローブが均質に付着していた。そこで、このクロム蒸着面に近赤外レーザー集束光を顕微鏡下で照射して局所加熱し、μmオーダーの空間分解能でDNAを熱変性したところ、局所分離することに成功した。解離したDNAはPCR増幅することができ、また残った固定DNAの方も、変性することなく可逆的に試料DNAを再結合した。また基板の蒸着クロムを面電極としてDNAを基板表面に誘導することができた。さらに、試料DNAが特定の領域としか結合しないこと、特定の領域のDNAのみを回収できることを確認した。以上3つの技術を実現したことによって、本研究課題を推進するための第一歩を踏み出すことができたと考える

  • Study of Life Science as Complex Systems

    　View Summary

    We have set up the basis of complex systems biology, to unveil universal features underlying all life systems, by taking a constructive approach, to set up a simple system both experimentally and theoretically.(1)Synthesis of in-vitro artificial replication system consisting of DNA and DNA polymerase and others. Theoretical demonstration that molecules minority in number start to play the role of heredity, in the sense that they control the behavior of a cell relatively strongly and are preserved well. This theory is confirmed by the above experiment.(2)Success of protein synthesis and RNA replication in liposome, observation and construction of stable self-replication of liposomes, and DNA hybridization on liposome.(3)Theoretical discovery of universal statistical laws of chemical abundances in a cell that sustains recursive production, i.e., a power law in average gene expression and log-normal distribution of the abundances of each chemicals, as is confirmed experimentally.(4)In-vitro genesis of almost all organs from Xenopous undifferentiated cells, using activin and a few other proteins. Discovery of jump-over phenomena and community effect. Demonstration that the constructed eye and heart tissues work normally after transplantation to organisms.(5)Theory of cell differentiation and developmental process based on a coupled dynamical systems, to show robustness and irreversibility.(6)Construction of differentiation by E Coli by using embedded gene network.(7)Evolution of E Coli to show that diversity is induced in a crowded condition.(8)Proposition of a theory of symbiotic sympatric speciation.(9)Construction of symbiotic system by E Coli and amoeba.(10)Theoretical proposition that evolution speed is proportional to phenotypic fluctuation of clones, as confirmed by artificial selection experiment to increase fluorescence of protein in E Coli.(11)Development of an equipment system that allows for long-term singe cell observation, manipulation, and on-chip cell sorter

  • マイクロファブリケーションを用いた単一細胞実時間解析

    　View Summary

    研究代表者(安田)はH11年度に(株)日立製作所より現職に転出して、新たに研究室を立ち上げ、H12年度「ゲノム生物学」の上記予算配分を利用することで、本提案にもある上記研究を開始した。本研究は以下に述べる3つのステージからなると考えている。すなわち、1)細胞を1細胞単位で隔離し連続培養観察できる装置系の開発、2)隔離した1細胞のDNA・mRNAを回収・分析して遺伝子多型解析・mRNA発現定量解析技術の開発、3)実際にモデル細胞(大腸菌を検討)を用いた細胞機能と遺伝子多型、mRNA発現量との関係の計測である。H12年度は、上記1)の「1細胞連続培養観察装置系」を開発した。装置は、スライドガラスに径30ミクロン程度の穴をマイクロ加工技術で掘り、この中に大腸菌を1匹閉じ込めた後、半透膜で上面をシール(ガラスと半透膜とはビオチン・アビジン結合で接着)したもので、さらにこの半透膜の上に培養液還流槽を設けることで、一定の培養溶液条件下での1細胞の活動を連続で顕微鏡観察できるものである。さらに光ピンセットと組み合わせることで特定の細胞を選択することも可能である。実際、本装置を用いることで、大腸菌1細胞の成長(伸長)速度、分裂周期を測定したり、細胞数を増やして相互衝突することが成長・細胞分裂にどのような影響をもたらすか、単離した1細胞が分裂してできた子細胞と親細胞との成長速度・分裂周期の違いなど従来の測定では計測できなかった1細胞の振る舞いを測定し、同一の遺伝子を持つ細胞相互の機能の違い等も測定できるようになった(論文2報投稿中)

  • Mechanisms underlying integration of synaptic plasticity in neuronal networks

    　View Summary

    Activity-dependent modification of synaptic connections probably plays a key role in both proper network formation during development and learning and memory. Based on the capability of multi-site stimulation, MEA recording was applied to see modification of evoked responses induced by repetitive application of temporally correlated stimuli. Cortical neurons show developmental changes in spontaneous activity and reach the steady state after about one month in vitro. Evoked responses also depend on their developmental stages. Thus, in this work, matured cultures of more than 40 days in vitro were used for recording. A series of recording consists of (1) evoked responses to test stimuli and (2) responses to the correlated stimuli. The test stimuli were composed of 100 times of single pulse stimulus from site A and another 100 times from site B. Each single-site stimulation was applied every six seconds. The correlated stimuli consisted of 100 times of double pulses. The first pulse applied from site A was followed by the second pulse from the site B with a fixed time delay. Time delays of 100, 50, 20, 10, and 0 ms were tested. The total process of the experiment was composed of 6 sets of test stimuli and 5 sets of correlated stimuli: test1-A＆B100-test2-A＆B50-test3-A＆B20-test4-A＆B10-tests-A＆B0-test6. The evoked activity consisted of early and late components. At the initial state, almost no late components were recorded. After the correlated stimuli, strong late components appeared. The late components were detected after about 30 ms, and 20 ms, respectively. To analyze relationship between induced activity-changes and the applied correlated stimuli, cross-correlation functions were calculated. These results suggested that the properties of the applied correlated stimuli might be reflected in the spatio-temporal structures in the evoked responses

  • Development of On-chip Cellomoics Analysis System for Studies on "Community Effect of Cells"

    　View Summary

    We began a series of studies aimed at developing methods and systems of analyzing epigenetic information in cells, as well as that of genetic information, to expand our understanding of how living systems are determined. Because cells are minimum units reflecting epigenetic information, which is considered to map the history of a parallel-processing recurrent network of biochemical reactions, their behaviors cannot be explained by considering only conventional DNA information-processing events. The role of epigenetic information on cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behavior observed under conditions chosen to reveal adaptation processes and community effects. A system of analyzing epigenetic information was developed starting from the twin complementary viewpoints of cell regulation as an 'algebraic' system (emphasis on temporal aspects) and as a 'geometric' system (emphasis on spatial aspects). The knowlege acquired from this study may lead to the use of cells that fully control practical applications like cell-based drug screening and the regeneration of organs

  • Analysis of propagation manners of paramyxoviruses in neural cells.

    　View Summary

    Both Measles and Nipah virus causes severe acute or late-onset encephalitis in human. In this study, we aimed to investigate the mechanisms of measles and nipah virus spread between neural cells. We established the AMCA (on-chip agarose microchamber array) system for primary neural cells, and elucidated the propagation manner of MV to neighboring cells. By using fluorescent labeled- viral protein, a new domain, which was important for interaction of NiV N and P protein, was identified. Further, we investigated NiV spread in African green monkey by using EGFP-expressing recombinant NiV. The results indicated that lethal infection to CNS occurred after systemic infection

▼display all

Presentations

  • Development of sprouting vascular endothelial cell collection method using flexible design of Matrigel for expression analysis

    Yuki Yamanaka, Kento Iida, Ryuji Takano, Hiromichi Hashimoto, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Selective digestion of Ba2+/Ca2+ alginate microdroplets for single-cell-analysis

    Masao Odaka, Moe Iwamura, Ayako Kawai, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Development of size filtration-imaging cell sorter for real time selective collection of circulating tumor cells (CTCs) in blood

    Moe Iwamura, Kenji Matsuura, Ayako Kawai, Masao Odaka, Akihiro Hattori, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Quantitative evaluation of preciseness in design copy in microfabrication procedures of circulating tumor cell cluster size-filtration

    Ayako Kawai, Moe Iwamura, kenji Matsuura, Akihiro Hattori, Masao Odaka, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Development of a method to track conductions in cardiomyocyte network with a multi-electrode system

    Kazufumi Sakamoto, Natsuki Seki, Shota Aoki, Naoki Takahashi, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Direct observation of blood vein formation dynamics exploiting flexible three-dimensional gelatin-gel microfabrication technology

    Kento Iida, Yuki Yamanaka, Hiromichi Hashimoto, Ryuji Takano, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Analysis of neglecting phase in phagocytosis of macrophages using on-chip sequential single-point phagocytoses measurement assay

    Yoshiki Nakata, Yuya Furumoto, Toshiki Azuma, Amane Yoshida, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Evaluation of photo-thermal three-dimensional gelatin-gel microfabrication technology for clarification of endothelial cells’ dynamics

    Hiromichi Hashimoto, Kento Iida, Yuki Yamanaka, Ryuji Takano, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Identifying the maximum size of phagocytosis in macrophages using on-chip single cell measurement assay

    Amane Yoshida, Yoshiki Nakata, Yuya Furumoto, Toshiki Azuma, Akihiro Hattori, Kenji Matsuura, Masao Odaka, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Hysteresis of single point sequential phagocytoses in macrophages using on-chip single cell measurement assay

    Toshki Azuma, Yoshiki Nakata, Yuya Furumoto, Amane Yoshida, Akihiro Hattori, Kenji Matsuura, Masao Odaka, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Development of free-flow assay for precise evaluation of phagocytosis efficiency of macrophages.

    Yuya Furumoto, Yoshiki Nakata, Toshiki Azuma, Amane Yoshida, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Repulsive interactions of two neurites elongated from two isolated hippocampal cells in agarose width-length-controlled microchannels.

    Yuhei Tanaka, Takahito Kikuchi, Shota Aoki, Akihiro Hattori, Kenji Matsuura, Masao Odaka, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Extracellular field potential change analysis of spontaneous firing of an isolated neuron by an on-chip multi-electrode array system.

    Shota Aoki, Takahito Kikuchi, Yuhei Tanaka, Kenji Matsuura, Akihiro Hattori, Masao Odaka, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • A 1064/1480-nm photo-thermal etching system with fiber optics for an accurate and non-invasive micropatterning of an agarose thin layer

    Takahito Kikuchi, Shota Aoki, Yuhei Tanaka, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • Community effect of cardiomyocytes in synchronous behavior of beating by constructing cell cluster (1): Experimental approach

    Naoki Takahashi, Akihiro Yamashita, Kazuhumi Sakamoto, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第56回日本生物物理学会年会  (岡山) 

    Presentation date： 2018.09

  • オンチップ・セロミクス：「履歴・記憶」と「集団効果」から見た細胞ネットワークの後天的情報の理解

    安田賢二

    第56回日本生物物理学会年会 CREST共催シンポジウム 生体機能の再構成によるセンシング技術とデバイス応用  (岡山) 

    Presentation date： 2018.09

  • On-chip Technologies for the Next generation of Diagnostics and Drug Discovery.

    Kenji Yasuda

    1st WABIOS mini-workshop: Systematic single-cell resolution analyses of cancer patients for next generation diagnostics and drug discovery  (Tokyo) 

    Presentation date： 2018.07

  • 構成的アプローチによる細胞ネットワークの集団効果の理解とその応用展開

    安田賢二

    応用物理学会 有機分子・バイオエレクトロニクス分科会３月研究会 「生命システムに学ぶセンシングおよび情報処理」  (東京) 

    Presentation date： 2018.03

  • 医療診断システムの開発と国際連携評価のデザイニング：早大海外研究開発拠点を基盤とした早稲田医理工社ブランディングの挑戦

    安田賢二

    早稲田大学 文部科学省私立大学研究ブランディング事業「医理工社連携による社会のデザイン」シンポジウム  (東京) 

    Presentation date： 2018.02

  • Time Course Change of Clustered Circulating Tumor Cell in Cancer Metastasis Blood Investigated with Imaging Biomarkers by on-Chip Multi-Imaging Cell Sorter.

    M. Odaka, A. Hattori, K. Matsuura, M. Iwamura, Y. Yamanaka, K. Iida, K. Yasuda

    The 30th International Microprocesses and Nanotechnology Conference (MNC 2017)  (Jeju) 

    Presentation date： 2017.11

  • Origin of cardiomyocyte cluster beating intervals: Elucidation of selection rule of interbeat intervals of cardiomyocyte network

    Naoki Takahashi, Natuki Seki, Masao Odaka, Hideyuki Terazono, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Analysis of sequential single point phagocytosises in macrophages using on-chip single cell measurement assay

    Yoshiki Nakata, Yuya Furumoto, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Hideyuki Terazono, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Adaptation of field potential duration in cardiomyocyte clusters under forced electrical stimulation intervals

    Natsuki Seki, Naoki Takahashi, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Optimization of antigen of macrophage phagocytosis using on-chip single cell measurement assay

    Yuya Furumoto, Yoshiki Nakata, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Monitoring of circulating tumor cell clusters in blood using size classifying imaging cell sorter.

    Moe Iwamura, Masao Odaka, Yuki Yamanaka, Kento Iida, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Development of real time microfabrication technology of nano-particle suspended agarose microstructures with focused photo-thermaletching

    Yuki Yamanaka, Kento Iida, Moe Iwamura, Masao Odaka, Kenji Matuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Development of real time microfabrication technology of gelatin with focused photo-thermal etching

    Kento Iida, Yuki Yamanaka, Moe Iwamura, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • A simple method for encapsulating single cells in alginate microspheres

    Masao Odaka, Akihiro Hattori, Kenji Matsuura, Moe Iwamura, Yuki Yamanaka, Kento Iida, W.Davis Ronald, D.Crosby Laurel, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Neurite elongation characteristics in the width-controlled channels using an in situ on-chip photothermal microfabrication assay

    Takahito Kikuchi, Shota Aoki, Hideyuki Terazono, Kenji Matsuura, Akihiro Hattori, Masao Odaka, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Extracellular electrophysiological measurement of spontaneous firing of single neurons in neuronal circuit using expandable on-chip assay.

    Shota Aoki, Takahito Kikuchi, Kenji Matsuura, Akihiro Hattori, Masao Odaka, Kenji Yasuda

    第55回日本生物物理学会年会  (熊本) 

    Presentation date： 2017.09

  • Development of on-chip dual measurement system for quasi-in vivo screening of cardiotoxicity using extracellular field potential recording and optical displacement analysis of single cells

    A. Hattori, N. Takahashi, M. Odaka, K. Matsuura, H. Terazono, N. Seki, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Studies on spatiotemporal adaptive regulation mechanism of macrophage phagocytosis: response of multiple stimulations due to physical contacts with multiway optical tweezers

    Y. Nakata, Y. Furumoto, M. Odaka, A. Hattori, K. Matsuura, H. Terazono, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Minimum width of artificial neuronal circuit patterns for stable elongation of neurites.

    T. Kikuchi, S. Aoki, M. Odaka, A. Hattori, K. Matsuura, H. Terazono, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Origin of cardiomyocyte cluster beating rythms: Elucidation of selection rule of interbeat intervals of cardiomyocyte network from single cells.

    N. Takahashi, N. Seki, H. Terazono, M. Odaka, A. Hattori, K. Matsuura, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Time course change of circulating tumor cell clusters in blood evaluated by imaging biomarkers of on-chip multi-imaging cell sorter

    M. Odaka, M. Iwamura, A. Hattori, K. Matsuura, H. Terazono, Y. Yamanaka, K. Iida, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • On-chip multi-imaging flowcytometry for non-labeled detection of cell clusters in blood with imaging biomarkers.

    M. Iwamura, Y. Yamanaka, K. Iida, M. Odaka, A. Hattori, K. Matsuura, H. Terazono, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Real time on-chip imaging cell sorter for shape recognition of target cells in droplets.

    M. Girault, H. Kim, K. Matsuura, M. Odaka, A. Hattori, H. Terazono, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Evaluation of cell-to-cell conduction on one-dimensional line of cardiac muscle cells network for in vitro predictive cardiotoxicity measurement beyond cell-based drug discovery electrophysiology.

    K. Matsuura, M. Iwamura, N. Takahashi, Y. Yamanaka, N. Seki, M. Odaka, A. Hattori, H. Terazono, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • Microfabrication techniques for observing neuronal transmission pathway.

    H. Terazono, A. Hattori, M. Odaka, K. Matsuura, K. Yasuda

    The 5th International symposium for Bioimaging Joint symposium on Bioimaging between Singapore and Japan  (Singapore) 

    Presentation date： 2017.05

  • 日本生物物理学会連携シンポジウム 「生物物理学的手法による生理学研究の新展開」

    安田賢二

    第94回日本生理学会大会  (浜松) 

    Presentation date： 2017.03

  • Development of Functional On-Chip Imaging Cell Sorter for Identification of Non-Labeled Circulating Tumor Cells

    Masao Odaka, Akihiro Hattori, Kenji Matsuura, Hideyuki Terazono, Moe Iwamura, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Development of Size Classifying Imaging Cell Sorter for Identifying of Circulating Tumor Cells

    Moe Iwamura, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Hideyuki Terazono, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Minimum Requirements of Microchannel Patterns for Building of Stable Neuronal Circuits in On-chip Cell Network Assa

    Takahito Kikuchi, Hideyuki Terazono, Kenji Matsuura, Akihiro Hattori, Masao Odaka, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Development of On-chip Cardiomyocyte Network Analysis Assay for Understanding of Fluctuation Correlation in Cell-to-cell Conduction

    Naoki Takahashi, Hideyuki Terazono, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Development of a single cell cultivating method using a microdroplets forming technique for sorting specific cells

    Hideyuki Terazono, Masao Odaka, Akihiro Hattori, Kenji Matsuura, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Studies on regulation mechanism of multiple phagocytosis of macrophage by single cell on-chip measurement assay

    Yoshiki Nakata, Hideyuki Terazono, Masao Odaka, Kenji Matsuura, Akihiro Hattori, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • Community effect of cardiomyocytes in beating rhythms is ruled by stable cells

    Tatsuya Hayashi, Tetsuji Tokihiro, Hiroki, Kurihara, Fumimasa Nomura, Kenji Yasuda

    第54回日本生物物理学会年会  (つくば) 

    Presentation date： 2016.11

  • セッション II 「細胞を作って・測って・利用するテクノロジーの最前線」

    安田賢二

    「細胞を創る」研究会 9.0  (東京) 

    Presentation date： 2016.11

  • オンチップquasi-in vivo臓器モデルを用いた創薬、診断支援技術

    安田賢二

    BioJapan 2016  (横浜) 

    Presentation date： 2016.10

  • Development of Flexible Expandable On-chip Multi-unit Combinatorial Extracellular Field Potential Measurement System For Generation of Cell Network Electrophysiology.

    A. Hattori, F. Nomura, H. Terazono, K. Matsuura, M. Odaka, K. Yasuda

    The International and Interdisciplinary Symposium 2016 “Towards a New Era of Cardiovascular Research” (ISC2016)  (Tokyo) 

    Presentation date： 2016.07

  • On-chip cellomics technology: Soft nanotechnology for constructive cell network researches in life science, drug discovery, and medical diagnostics.

    Kenji Yasuda

    the International and Interdisciplinary Symposium 2016 “Towards a New Era of Cardiovascular Research” (ISC2016)  (Tokyo) 

    Presentation date： 2016.07

  • A micropatterning technique using a cell‐surface specific binding DNA aptamer.

    H. Terazono, H. Kim, F. Nomura, A. Hattori, K. Yasuda

    The American Society for Cell Biology Annual Meeting 2015 (ASCB2015)  (San Diego) 

    Presentation date： 2015.12

  • オンチップ・セロミクステクノロジー：（副題）ソフトナノテクノロジーを用いた構成的細胞ネットワーク技術の生命科学研究、創薬支援技術から早期医療診断応用まで

    安田賢二

    第35回表面科学学術講演会 第56回真空に関する連合講演会 ソフトナノテクノロジー研究部会シンポジウム  (つくば) 

    Presentation date： 2015.12

  • Automatic sorting system and incubation at single cell level using microfluidic devices

    M. Girault, A. Hattori, H. Kim, K. Matsuura, M. Odaka, H. Terazono, K. Yasuda

    The 16th Japanese-French Oceanography Symposium  (Shiogama) 

    Presentation date： 2015.11

  • Bright Field/Fluorescent Dual Imaging Cell Sorter System for Precise Purification of Circulating Tumor Cells

    H. Kim, M. Odaka, M. Girault, A. Hattori, H. Terazono, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Predictive Human Cardiotoxicity Measurement Assay Using a Lined-Up Thousand Cardiomyocyte Cell Network

    A. Hattori, F. Nomura, H. Kim, H. Terazono, K. Matsuura, M. Odaka, M. Girault, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Development of a Micropatterning Technique Using Cell-surface Specific Binding DNA Aptamer

    H. Terazono, H. Kim, A. Hattori, F. Nomura, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Identification of Cell Clusters in Cancer Cell-implanted Rat Bloods Based on Measurements of Imaging Biomarkers Using on-chip Multi-imaging Flow Cytometry System

    M. Odaka, H. Kim, M. Girault, A. Hattori, H. Terazono, K. Matsuura, F. Nomura, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Morphology Imaging Microdroplet Sorting System for Identification and Acquisition of Target Objects in Droplets

    M. Girault, A. Hattori, H. Kim, S. Kawada, K. Matsuura, M. Odaka, H. Terazono, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Cardiotoxicity Prediction Analysis Using Electrophysiological Signals in Lined Up Cardiomyocyte-network

    F. Nomura, H. Kurotobi, Y. Sugio, H. Terazono, K. Yasuda

    28th International Microprocesses and Nanotechnology Conference (MNC2015)  (Toyama) 

    Presentation date： 2015.11

  • Studies on identification of cells using visible morphological information using bright field/fluorescent multi-imaging flow cytometer

    Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Masao Odaka, Kenji Matsuura, Mathias Girault, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Measurement of extracellular potential in single cardiomyocyte

    Jyunpei Shimada, Kenji Yasuda, Tomoyuki Kaneko

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Contribution of depletion effect to size-specific target cell purification using mirometer-sized concave structures

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Akihiro Hattori, Kenji Matsuura, Fumimasa Nomura, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Evaluation of imaging biomarkers for identification of single cancer cells in blood by on-chip multi imaging cell system

    Masao Odaka, Hyonchol Kim, Mathias Girault, Akihiro Hattori, Hideyuki Terazono, Kenji Matsuura, Fumimasa Nomura, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Development of impedance measurement system for identification of cells

    Kenji Matsuura, Fumimasa Nomura, Akihiro Hattori, Hiromi Kurotobi, Masao Odaka, Hyonchol Kim, Hideyuki Terazono, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Development of flexible expandable on-chip multi electrode array system for cell-network measurement

    Fumimasa Nomura, Akihiro Hattori, Kenji Matsuura, Hiromi Kurotobi, Masao Odaka, Hyonchol Kim, Hideyuki Terazono, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Target imaging droplet sorting system: a shape identification method for recognition and sort target droplet with cell in real time

    Mathias Girault, Hyonchol Kim, Kenji Matsuura, Masao Odaka, Hideyuki Terazono, Akihiro Hattori, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • Fabrication and functional evaluation of “neuronal sheet” using calcium alginate gel

    Hideyuki Terazono, Hyonchol Kim, Fumimasa Nomura, Kenji Yasuda

    第53回日本生物物理学会年会  (金沢) 

    Presentation date： 2015.09

  • 新規神経シート作製技術の開発と神経ネットワーク間のコミュニケーション解析

    寺薗 英之, 野村 典正, 服部 明弘, 金 賢徹, 安田 賢二

    第38回日本神経科学大会  (神戸) 

    Presentation date： 2015.07

  • 様々な元素で作製された機能的微粒子の1細胞計測技術への応用

    金賢徹, 寺薗英之, 竹井弘之, 安田賢二

    M&BE応用物理学会 有機分子・バイオエレクトロニクス分科会 研究会  (富山) 

    Presentation date： 2015.05

  • Constructive approach to understand neuronal communication by controlling spatial patterns using microprocessing and cell-sheet technique.

    Hideyuki Terazono, Fumimasa Nomura, Akihiro Hattori, Kenji Yasuda

    2015 The Bridging Biomedical Worlds From Neural Circuitry to Neurotechnology  (Tokyo) 

    Presentation date： 2015.05

  • On-chip Cellomics Assay: Re-constructive approach of single cells for functional quasi-in vivo tissue/Organ models on a chip for drug discovery and toxicology

    Kenji Yasuda

    9th Asian Biophysics Association (ABA) Symposium  (Hangzou) 

    Presentation date： 2015.05

  • 神経細胞シート構築技術の開発と神経ネットワーク間コミュニケーションの電気生理学的解析

    寺薗 英之, 野村 典正, 安田 賢二

    生命動態システム科学四拠点・CREST・PREST合同シンポジウム  (京都) 

    Presentation date： 2015.03

  • 構成的アプローチによる心筋細胞ネットワークの拍動同期化ダイナミクスの計測と解析

    野村 典正, 寺薗 英之, 安田 賢二

    生命動態システム科学四拠点・CREST・PREST合同シンポジウム  (京都) 

    Presentation date： 2015.03

  • On-chip quasi-in vivo predictive cardiotoxicity assay using spatiotemporal fluctuation measurement on human cardiomyocyte cell-network

    F. Nomura, T. Kaneko, H. Terazono, K. Yasuda

    Biophysical Society 59th Annual Meeting  (Baltimore) 

    Presentation date： 2015.02

  • オンチップセロミクス：構成的アプローチによる神経ネットワーク構築の試み

    安田賢二

    第7回 CBIR・ONSA若手インスパイアシンポジウム  (東京) 

    Presentation date： 2015.02

  • On-chip Cellomics System: Re-constructive Approach of Single Cells for Functional quasi in vivo Tissue/Organ Models on a Chip for Drug Discovery and Toxicology

    Kenji Yasuda

    2nd NeuroCMOS Workshop  (Kobe) 

    Presentation date： 2015.01

  • 基調講演

    安田賢二

    第4回ナノメディシン分子科学若手の会  (東京) 

    Presentation date： 2015.01

  • Development of single strand DNA aptamer for cell surface of human umbilical vein endothelial cell.

    H. Terazono, H. Kim, F. Nomura, Y. Wada, Y. Kurihara, H. Kurihara, K. Yasuda

    ASCB2014  (Philadelphia) 

    Presentation date： 2014.12

  • Size-Specific Target Cell Purification Exploiting Depletion Effect on Cup-Shaped Superparamagnetic Hemispheres

    H. Kim, H. Terazono, H. Takei, K. Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • Development of the Algorithm for Recognition and Identification of Target Cells Using Imaging Biomarkers for On-Chip Multi-Imaging Cell Sorter

    M. Odaka, H. Kim, M. Girault, A. Hattori, H. Terazono, K. Matsuura, K. Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • High-Throughput Nano-droplet Array Polymerase Chain Reaction System with Fast and Homogeneous Temperature Control for 24/96/384 Sample Plate

    K. Matsuura, H. Terazono, H. Kim, A. Hattori, F. Nomura, K. Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • Control the formation of micro-droplets with homogenous size in on-chip microfluidics system: a pressure-controlled approach

    M. Girault, A. Hattori, H. Kim, S. Kawada, K. Matsuura, M. Odaka, H. Terazono, K. Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • Electrophysiological Analysis of Single Neurons in Genetically Micropatterned Constructive Neuronal Networks

    H. Terazono, H. Kim, K. Matsuura, H. Takei, A. Hattori, K. Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • Electrophysiological Impedance Spectrum Analysis of Cardiomyocytes using on-chip Multimicroelectrode Impedance Analyzer

    Fumimasa Nomura, Kenji Matsuura, Akihiro Hattori, Hiromi Kurotobi, Hideyuki Terazono, Kenji Yasuda

    27th International Microprocesses and Nanotechnology Conference (MNC2014)  (Fukuoka) 

    Presentation date： 2014.11

  • １細胞からのオンチップ・テクノロジー：生命科学研究、創薬支援技術から早期医療診断技術まで

    安田賢二

    高分子同友会 新材料の創製(反応、合成、バイオ、触媒、解析、機能等)について勉強する会  (東京) 

    Presentation date： 2014.11

  • On-chip quasi-in vivo cardiomyocyte network screening assay for predictive cardiotoxicity beyond hERG and QT assays.

    Kenji Yasuda

    13th Surugadai International Symposium & Joint Usage/Research Program of Medical Research Institute International Symposium  (Tokyo) 

    Presentation date： 2014.11

  • Development of On-Chip Multi-Imaging Cell Sorter System for Identification of Clustered Circulating Tumor Cells

    Hyonchol Kim, Hideyuki Terazono, Yoshiyasu Nakamura, Kazuko Sakai, Akihiro Hattori, Masao Odaka, Girault Mathias, Kazuto Nishio, Youhei Miyagi, Kenji Yasuda

    ACTC2014  (Crete) 

    Presentation date： 2014.10

  • A temperature-control technique with great accuracy and uniformity for a ANSI/SBS plate for 3-min PCR and a melting curve analysis

    Hideyuki Terazono, Hyonchol Kim, Kenji Matsuura, Akihiro Hattori, Fumimasa Nomura, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Non-firing impedance-based electrophysiological analysis of single cells on micro-electrode arrays

    Kenji Matsuura, Akihiro Hattori, Fumimasa Nomura, Hideyuki Terazono, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Optimization of the cell encapsulation in the water in oil droplet using 3D printed object

    Mathias Girault, Akihiro Hattori, Hyonchol Kim, Kenji Matsuura, Masao Odaka, Yumi Mikami, Hideyuki Terazono, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Imaging biomarkers for identification of target cells: Identification of clustered circulating tumor cells as an example

    Hyonchol Kim, Hideyuki Terazono, Akihiro Hattori, Masao Odaka, Mathias Girault, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Development of the cell imaging biomarker identification algorism for on-chip multi imaging cell sorter system

    Masao Odaka, Hyonchol Kim, Mathias Girault, Akihiro Hattori, Hideyuki Terazono, Kenji Matsuura, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Quasi-in vivo pre-clinical model for cardiac toxicity using spatiotemporal fluctuation measurement on human cardiomyocyte cell-network

    Fumimasa Nomura, Tomoyuki Kaneko, Hideyuki Terazono, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • Investigation of wide range optical set-up for simultaneous real-time analysis of 96-well SBS formatted samples

    Akihiro Hattori, Hideyuki Terazono, Kenji Matsuura, Hyonchol Kim, Masao Odaka, Mathias Girault, Kenji Yasuda

    第52回日本生物物理学会年会  (札幌) 

    Presentation date： 2014.09

  • 超常磁性カップの作製とサイズ選択的細胞回収

    金賢徹, 寺薗英之, 竹井弘之, 安田賢二

    第75回応用物理学会秋季学術講演会  (札幌) 

    Presentation date： 2014.09

  • オンチップ人工神経回路作製技術の開発と電気生理学的計測

    寺薗 英之, 野村 典正, 服部 明弘, 金 賢徹, 安田 賢二

    第37回日本神経科学大会  (横浜) 

    Presentation date： 2014.09

  • Live demonstration: Some acoustic properties of cooked spaghetti

    Kenji Yasuda

    Acoustofluidics 2014  (Plato) 

    Presentation date： 2014.09

  • オンチップ・セロミクステクノロジー：構成的細胞ネットワーク技術の生命科学研究、創薬支援技術から早期医療診断応用まで

    安田賢二

    2014年度 生物工学フォーラム「先端技術による新たなバイオテクノロジー」  (和光) 

    Presentation date： 2014.07

  • 早期がん診断を実現するナノバイオ計測技術

    安田賢二

    横浜ライフイノベーション特区セミナー  (横浜) 

    Presentation date： 2014.07

  • ナノカップを用いた細胞精製、in situゲノム・プロテオーム解析技術の開発

    安田賢二

    BIO tech 2014 －国際バイオテクノロジー展/技術会議－アカデミックフォーラム  (東京) 

    Presentation date： 2014.05

  • 創薬支援を目指したオンチップQuasi-in vivo 細胞ネットワークスクリーニングアッセイ

    安田賢二

    第13回日本再生医療学会総会  (京都) 

    Presentation date： 2014.03

  • １細胞からのオンチップ・テクノロジー：生命科学研究、創薬支援技術から早期医療診断技術まで

    安田賢二

    応用物理学会有機分子バイオエレクトロニクス分科会3月研究会  (東京) 

    Presentation date： 2014.03

  • Application Of Cup Shaped Superparamagnetic Hemispheres For Size Selective Cell Purification

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    58th Annual Meeting of Biophysical Society  (San Francisco) 

    Presentation date： 2014.02

  • Development of "Adaptive SEM" Technology for in situ Genome/Proteome Expression Analysis in Single Cell Level

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    IMC2014  (Prague) 

    Presentation date： 2014.02

  • Nano-Cups: Fabrication and Application of Cup-Shaped Functional Nano-Particles for Cell Biology

    Kenji Yasuda

    1st International Symposium on Nanoparticles/Nanomaterial and Applications  (Lisbon) 

    Presentation date： 2014.01

  • Two-Dimensionally Indexed Precise-Size-Controlled Multi-Metal Nano-Particle Probe Set with Adaptive-Electron Microscopy for Identification of Genome/Proteome Expression Profiles

    Kenji Yasuda

    1st International Symposium on Nanoparticles/Nanomaterial and Applications  (Lisbon) 

    Presentation date： 2014.01

  • イメージングバイオマーカーとマルチイメージングセルソーターによる無染色でのより正確な血管中のがん細胞塊の同定個人差や小さな病変も見逃さないバイオ計測技術の開発

    安田賢二

    第13回国際ナノテクノロジー総合展・技術会議（nano tech 2014）2014 シーズ＆ニーズセミナー  (東京) 

    Presentation date： 2014.01

  • iPS心筋細胞の特性と心毒性検査システム

    野村典正, 寺薗英之, 安田賢二

    筋生理の集い  (東京) 

    Presentation date： 2013.12

  • DNAアプタマーを用いた心筋細胞精製技術の検討

    寺薗英之, 野村典正, 安田賢二

    筋生理の集い  (東京) 

    Presentation date： 2013.12

  • Complementary Techniques for Non-Invasive Cell Identification, Separation and Purification at Single-Cell Level for Cell-Based Life Science Research and Regenerative Medicine

    Kenji Yasuda, Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori

    12th US-Japan Sumposium on Drug Delivery Systems  (Maui) 

    Presentation date： 2013.12

  • Development of a new circulating tumor cell detection and isolation assay based on automated onchip imaging flow cytometry technology

    Kenji Yasuda, Hyonchol Kim, Hideyuki Terazono, Akihiro Hattori, Kenji Matsuura, Masao Odaka, Mathias Girault

    12th US-Japan Sumposium on Drug Delivery Systems  (Maui) 

    Presentation date： 2013.12

  • On-chip quasi-in vivo cardiomyocyte network screening assay for predictive cardiotoxicity beyond hERG and QT assays

    Kenji Yasuda, Fumimasa Nomura, Hideyuki Terazono

    12th US-Japan Sumposium on Drug Delivery Systems  (Maui) 

    Presentation date： 2013.12

  • Temperature-Shift Speed Dependence of Nonspecific Amplification of Polmerase Chain Reaction Ezamined by 1480 nm Photothermal Transition Speed Controllable Ultra-High-Speed Polymerase Chain Reaction System

    Hideyuki Terazono, Akihiro Hattori, Hyonchol Kim, Hiroyuki Takei, Fumimasa Nomura, Kenji Yasuda

    ASCB2013  (New Orleans) 

    Presentation date： 2013.12

  • Quantitative Evaluation of Origin of Changes in Electrophysiological Properties of Cells on Micro Electrodes using Impedances Analysis Measurement Setup

    Kenji Matsuura, Akihiro Hattori, Fumimasa Nomura, Tomoyo Hamada, Hideyuki Terazono, Kenji Yasuda

    MNC2013  (Sapporo) 

    Presentation date： 2013.11

  • Development of On-chip Flow Cytometry System based on Bright Field/Fluorescent Dual-image Analysis

    Akihiro Hattori, Hyonchol Kim, Kenji Yasuda

    MNC2013  (Sapporo) 

    Presentation date： 2013.11

  • Development of Ultra-high-speed Microfluidic Submicron-droplet PCR Device using Circulating Water System and a photo detector

    Hideyuki Terazono, Hyonchol Kim, Hiroyuki Takei, Akihiro Hattori, Kenji Yasuda

    MNC2013  (Sapporo) 

    Presentation date： 2013.11

  • Importance of Spatial Arrangement of Cell Network Patterns for Precise and Stable Measurement of in Vitro Properties of Cells

    Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Matsu-ura, Hideyuki Terazono, Kenji Yasuda

    MNC2013  (Sapporo) 

    Presentation date： 2013.11

  • Fabrication of Cup-Shaped Superparamagnetic Metal Hemispheres for Size-Selective Target Cell Collection

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    MNC2013  (Sapporo) 

    Presentation date： 2013.11

  • オンチップ・セロミクス １細胞からの生命システムの理解を目指して

    安田賢二

    （独）日本学術振興会 ゲノムテクノロジー第164委員会第41回研究会  (東京) 

    Presentation date： 2013.11

  • Non-invasive identification and purification method of target cardiomyocyte cells using cell-surface-binding ssDNA aptamers

    Hideyuki TERAZONO, Hyonchol KIM, Fumimasa NOMURA, Kenji YASUDA

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Fabrication of Superparamagnetic Metal Cups for Size-Selective Cell Collection

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • A comparative study on electrophysiological properties of human iPSand ES-derived cardiomyocytes

    Fernando Lopez-Redondo, Junko Kurokawa, Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Tetsushi Furukawa, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Flow cytometry identification of nanocyanobacteria and their limiting factors in the North Pacific Subtropical Gyre

    Mathias Girault, Hisayuki Arakawa, Gerald Gregori, Fuminori Hashihama, Hyonchol Kim, Masao Odaka, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Importance of spatial arrangement and community size on cardiomyocyte network for precise and stable in vitro drug screening measurement

    Fumimasa Nomura, Tomoyo Hamada, Hideyuki Terazono, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Measurement of contractile direction on single-shape-controlled cardiomyocytes by on-chip optical image analysis system

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Development of On-chip Multi-imaging Flow Cytometer System using Real-time Bright Field/Fluorescent Dual Image Analysis High-speed Camera

    Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Masao Odaka, Mathias Girault, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Real time image analysis technology for identification and collection of clustered cells using on-chip multi-imaging cell sorter

    Masao Odaka, Mathias Girault, Hyonchol Kim, Hideyuki Terazono, Akihiro Hattori, Kenji Yasuda

    第51回日本生物物理学会年会  (京都) 

    Presentation date： 2013.10

  • Development of Screening Technology of Circulating Tumor Cells Using Multi-imaging Cell Sorter

    Kenji Yasuda

    Bio Japan 2013  (Tokyo) 

    Presentation date： 2013.10

  • On-chip cellomics technology for studying dynamics of cellular networks

    Kenji Yasuda

    5th Hiroshima Conference on Education and Science in Dentistry  (Hiroshima) 

    Presentation date： 2013.10

  • Toward Quasi-In Vivo from In Vitro Assay (IV): Fabrication of Direction-Controlled Artificial Neuronal Networks Using Agarose-Microetching Method and Single-Cell-Electrodes for Quantitative Evaluation of Neuropsychiatric Disorders

    Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori, Fumimasa Nomura, Tomoyo Hamada, Kenji Yasuda

    Safety Pharmacology Society 13th Annual Meeting  (Rotterdam) 

    Presentation date： 2013.09

  • Toward Quasi-In Vivo from In Vitro Assay (III): Noninvasive Identification and Purification Method of Target Cardiomyocyte Cells Using Nuclease Digestive Magnet-Beads-Attached ssDNA Aptamers

    Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori, Tomoyo Hamada, Fumimasa Nomura, Kenji Yasuda

    Safety Pharmacology Society 13th Annual Meeting  (Rotterdam) 

    Presentation date： 2013.09

  • Toward quasi-in vivo from in vitro assay (II). Importance of spatial arrangement of cardiomyocyte network for precise and stable in vitro drug screening measurementy

    Fumimasa Nomura, Tomoyo Hamada, Hideyuki Terazono, Kenji Yasuda

    Safety Pharmacology Society 13th Annual Meeting  (Rotterdam) 

    Presentation date： 2013.09

  • Toward quasi-in vivo from in vitro assay (I). Development of spatial conductance fluctuation measurement assay using a human cardiomyocyte line-network cell chip with multielectrode array system for in vitro predictive proarrhythmic cardiotoxicity

    Tomoyo Hamada, Fumimasa Nomura, Hideyuki Terazono, Akihiro Hattori, Peter Sartipy, Mitsuhiro Edagawa, Thomas Meyer, Kenji Yasuda

    Safety Pharmacology Society 13th Annual Meeting  (Rotterdam) 

    Presentation date： 2013.09

  • Evaluation of Fluctuation of Temporal Field Potential Duration and Spatial Conduction Time in Linear Network of Human-iPS Cell Derived Cardiomyocytes for Predictive Cardiotoxicity Measurement

    Yumiko Asahi, Yasuyuki Abe, Kiyoshi Takasuna, Atsushi Sanbuissho, Kenji Yasuda, Fumimasa Nomura, Tomoyo Hamada

    Safety Pharmacology Society 13th Annual Meeting  (Rotterdam) 

    Presentation date： 2013.09

  • オンチップ心筋細胞ネットワークスクリーニング系による心毒性予測技術の開発

    安田賢二

    早稲田大学第19回藤目記念セミナー  (軽井沢) 

    Presentation date： 2013.08

  • On-Chip Quasi-In Vivo iPS Cardiomyocyte Network Screening Assay for Predictive Cardiotoxicity beyond hERG and QT Assays

    Kenji Yasuda

    5th TMDU International Summer Program Symposium 2013  (Tokyo) 

    Presentation date： 2013.08

  • オンチップ細胞ネットワーク機能計測システム技術と創薬への応用

    安田賢二

    大日本住友製薬(株)講演会  (大阪) 

    Presentation date： 2013.07

  • On-Chip Cellomics: Single-Cell-Based Constructive Cell-Network Assay for Quasi-In Vivo Screening of Cardiotoxicity

    Kenji Yasuda

    35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC’13)  (Osaka) 

    Presentation date： 2013.07

  • 「１細胞」からの生命の理解を目指したバイオツール・デバイス 知るための「技術開発」を中心に

    安田賢二

    （独）科学技術振興機構 研究開発戦略センター １細胞解析の俯瞰に関するワークショップ  (東京) 

    Presentation date： 2013.07

  • オンチップ・セロミクステクノロジー：１細胞からの生命システムの理解と応用

    安田賢二

    理化学研究所細胞システムコロキウム SeriesⅣ Bioengineering and Biomechanics  (和光) 

    Presentation date： 2013.06

  • 金ナノ粒子標識とFE-SEM計数計測を組み合わせた生体分子高感度検出法の開発

    金賢徹, 竹井弘之, 寺薗英之, 安田賢二

    日本顕微鏡学会 第69回学術講演会  (大阪) 

    Presentation date： 2013.05

  • 超高速臨床診断・研究を可能にする小型オンチップ遺伝子診断システム

    安田賢二

    BIO tech 2013  (東京) 

    Presentation date： 2013.05

  • On-chip quasi-in vivo cardiomyocyte network screening assay for predictive cardiotoxicity beyond hERG and QT assays

    Kenji Yasuda

    Stem Cells & Cell Signaling -2013 Meeting  (Waltham) 

    Presentation date： 2013.05

  • On-chip quasi-in vivo pre-clinical cardiac toxicity: Testing compounds beyond hERG and QT assay using spatiotemporal human cardiomyocytes measurement

    Kenji Yasuda

    Cellectis社サイエンスセミナー“Stem cells in Drug Discovery”  (Tokyo) 

    Presentation date： 2013.05

  • On-chip cardiomyocyte network screening assay for predictive cardiotoxicity

    Kenji Yasuda

    HESI Cardiac Safety Committee Workshop: Stem Cell-Derived Cardiomyocytes as Models of Cardiac Pathobiology and Toxicity  (Cambridge) 

    Presentation date： 2013.03

  • 個人差や小さな病変も見逃さないバイオ計測技術の開発「早期がん診断を実現するナノバイオ計測技術」オンチップ・セロミクス計測技術開発から創薬支援・医療診断技術開発への展開

    安田賢二

    第３回 かながわ未来フォーラム「がん診断・最先端技術講演会」  (横浜) 

    Presentation date： 2013.03

  • Development of "Adaptive SEM"Technology for Genome/Proteome Expression Analysis in Single Cell Level

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    57th Annual Meeting of Biophysical Society  (Philadelphia) 

    Presentation date： 2013.02

  • Evaluation of On-chip quasi-in vivo cardiac toxicity assay for direct prediction of TdP occurrence using closed-loop-shaped cardiomyocyte network

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Kenji Yasuda

    57th Annual Meeting of Biophysical Society  (Philadelphia) 

    Presentation date： 2013.02

  • Human ES- and Induced Pluripotent Stem-Derived Cardiomyocytes. A Comparative Electrophysiological Study

    Fernando L?pez-Redondo, Junko Kurokawa, Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Kenji Yasuda, Tetsushi Furukawa

    57th Annual Meeting of Biophysical Society  (Philadelphia) 

    Presentation date： 2013.02

  • Simultaneous dual measurement of mechanical responses and electrophysiological properties of cardiomyocytes using on-chip optical image analysis and field potential recording system

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    57th Annual Meeting of Biophysical Society  (Philadelphia) 

    Presentation date： 2013.02

  • Long-term simultaneous dual measurement of electrophysiological properties and mechanical responses of cardiomyocytes using on-chip extracellular field potential recording and real-time optical image analysis.

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    The American Society for Cell Biology 2012 Annual Meeting  (San Francisco) 

    Presentation date： 2012.12

  • Non-invasive/destructive single cell purification method for re-cultivation of functionally identified specific cells using spot digestion of double alginate sol layers on a multielectrode array chip.

    Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    The American Society for Cell Biology 2012 Annual Meeting  (San Francisco) 

    Presentation date： 2012.12

  • セロミクス解析システムチップ

    安田賢二

    平成24年度北東北ナノメディカルクラスター研究会ウインターキャンプ  (田沢湖) 

    Presentation date： 2012.12

  • Ultra High-speed Microdroplet Polymerase Chain Reaction System for Three-step Reverse Transcription of Single Cells using On-chip Three-channel Switching High-speed Liquid Circulating Module

    Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Akihiro Hattori, Tomoyuki Kaneko, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Fabrication of Superparamagnetic Nano-particles having Various Diameters by Strict Controlling of Magnetic Material Thickness

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Tempospatial External Field Potential Fluctuation Measurement in Constructive Cardiomyocyte Network for in Vitro Predictive Cardiotoxicity

    Tomoyo Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Quantitative Evaluation of Quasi-electrocardiogram Measurement for Direct Prediction of Lethal Arrhythmic Beating Occurrence using Ring-shaped Cardiomyocyte Network with Ring Electrode Array

    Fumimasa Nomura, Tomoyuki Kaneko, Akihiro Hattori, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Development of On-Chip Dual Measurement System for Cardiac Contraction Flu Ctuation Assay using Simultaneous Recording of Extracellular Field Potential and Optical Image

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Surface Roughness of Cells as Index of Label-free Cell Identification and Separation in On-chip Imaging Cell Sorting System

    Akihiro Hattori, Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    25th International Microprocesses and Nanotechnology Conference(MNC2012)  (Kobe) 

    Presentation date： 2012.11

  • Toward quasi-in vivo from in vitro assay (V). Non-invasive precise purification of ventricular cells from mixture of differentiated human stem cell derived cardiomyocytes using spot digestion of double alginate layers on a multi-electrode array chip

    Hideyuki Terazono, Hyonchol Kim, Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Kenji Yasuda

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Toward quasi-in vivo from in vitro assay (IV). Quasi-electrocardiogram measurement for direct prediction of TdP occurrence using ring-shaped cardiomyocyte network with ring electrode array

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Kenji Yasuda

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Toward Quasi-In Vivo from In Vitro assay (III). Evaluation of Temporal Field Potential Duration Fluctuation and Spatial Conduction Velocity Fluctuation of Cardiomyocyte Network for In Vitro Predictive Cardiotoxicity Measurement

    Tomoyo Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Hideo Takamori, Yasuyuki Abe, Tomoko Sakakura, Kiyoshi Takasuna, Atsushi Sanbuissho, Kenji Yasuda

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Toward Quasi-in vivo from in vitro assay (II). Development of on-chip predictive cardiotoxicity assay for cardiac contraction fluctuation measurement using dual recording of electrical field potential and optical image analysis

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Toward quasi-in vivo from in vitro assay (I). On-chip cardiomyocyte network screening assay for predictive cardiotoxicity

    Kenji Yasuda, Fumimasa Nomura, Tomoyo Hamada, Tomoyuki Kaneko, Hideo Takamori, Yasuyuki Abe, Tomoko Sakakura, Kiyoshi Takasuna, Atsushi Sanbuissho

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Evaluation of ion channel trafficking of human stem cell derived cardiomyocytes for cardiotoxicity screening

    Yasuyuki Abe, Tomoko Sakakura, Kiyoshi Takasuna, Atsushi Sanbuissho, Fumimasa Nomura, Tomoyo Hamada, Tomoyuki Kaneko, Kenji Yasuda

    Safety Pharmacology Society 12th Annual Meeting  (Phoenix) 

    Presentation date： 2012.10

  • Quasi in vivoスクリーニング：細胞ネットワークを用いたin vitro創薬支援技術の最前線

    安田賢二

    平成24年度再生医療サポートビジネス懇話会  (京都) 

    Presentation date： 2012.10

  • Circulating Tumor Cell の検出と分離、画像型セルソーターのテクノロジー

    安田賢二

    第64回日本皮膚科学会西部支部学術大会  (広島) 

    Presentation date： 2012.10

  • 様々な粒径・材質のヤヌス粒子に対する機能付加法の検討

    金賢徹, 竹井弘之, 寺薗英之, 安田賢二

    第73回応用物理学会学術講演会  (松山) 

    Presentation date： 2012.09

  • Development of Dual Recording Assay for Cardiac Function Measurement using Electrical Field Potential and Optical Image Analysis

    Toru Shoji, Tomoyuki Kaneko, Fumimasa Nomura, Akihiro Hattori, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • Quantitative evaluation of cell separation method based on shape recognition using on-chip imaging cell sorter

    Akihiro Hattori, Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • A Non－destructive Culturing and Cell Sorting Method for Cardiomyocytes and Neurons Using an Alginate Layer

    Hideyuki Terazono, Hyonchol Kim, Akihiro Hattori, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • Fabrication of Superparamagnetic Janus Particles Having Various Size and Its Application for Non-Destructive Cell Sorting

    Hyonchol Kim, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • Evaluation of temporal fluctuation and spatial fluctuation on cardiomyocyte network for in vitro predictive cardiotoxicity measurement

    Tomoyo Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • On-chip quasi-in vivo cardiac toxicity assay using ring-shaped closed circuit microelectrode with lined-up cardiomyocyte network

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • Optimization of effective electrical stimulation protocol for cariomyocyte beating interval control in extracellular potential measurement assay in predictive cardiotoxicity testing

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    第50回日本生物物理学会年会  (名古屋) 

    Presentation date： 2012.09

  • Development of on-chip imaging flow cytometry technology for circulatingtumor cell analysis

    安田賢二

    第71回日本癌学会学術総会  (札幌) 

    Presentation date： 2012.09

  • On-chip cellomics: constructive cell network assay of cardiomyocytes, and neurons for quasi in-vivo drug discovery technology

    Kenji Yasuda

    University of Helsinki Viikki, Life Science Campus Seminar  (Helsinki) 

    Presentation date： 2012.06

  • 1細胞in situゲノムプロテオーム計測のためのFE-SEM定量反射電子分析法の開発

    金賢徹, 竹井弘之, 寺薗英之, 安田賢二

    日本顕微鏡学会 第68回学術講演会  (つくば) 

    Presentation date： 2012.05

  • わたしが研究者になった道 ?博士課程進学を考えている諸君に向けて、先輩からのメッセージ?

    安田賢二

    早稲田大学ホリスティック講演会  (東京) 

    Presentation date： 2012.05

  • Quasi-in vivo測定系：心毒性検査のための心筋細胞ネットワークの機能的再構築

    安田賢二

    第85回日本薬理学会年会  (京都) 

    Presentation date： 2012.03

  • Quasi-in Vivo Electrocardiogram Measurement Using Convolution of Field Potential Propagation in the On-Chip Cardiomyocytes Network Circuit

    Fumimasa Nomura, Tomoyuki Kaneko, Tomoyo Hamada, Akihiro Hattori, Kenji Yasuda

    Biophysical Society 56th Annual Meeting  (San Diego) 

    Presentation date： 2012.02

  • ウサギランゲンドルフ灌流心MAPD有用性評価 -サルテレメトリーQTc、モルモット乳頭筋APD及びヒトES細胞FPDとの比較-

    高森秀男, 前田優, 坂倉智子, 阿部泰之, 高砂浄, 金子智行, 野村典正, 浜田智代, 安田賢二

    第3回日本安全性薬理研究会学術年会  (東京) 

    Presentation date： 2012.02

  • Identification of Nano-Particle Labels Fabricated with Various Elements by "Adaptive SEM" Technology

    Hyonchol Kim, Terazono Hideyuki, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    The 6th International Symposium on Surface Science  (Tokyo) 

    Presentation date： 2011.12

  • Quantitative in situ Measurement of Target Biomolecules by Metal Nano-Particle Label Sets and “Adaptive SEM” Technology

    Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    The American Society for Cell Biology 51st Annual Meeting  (Denver) 

    Presentation date： 2011.12

  • Influence of fibroblasts on the synchronization of cardiomyocyte beating and community effect

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    The American Society for Cell Biology 51st Annual Meeting  (Denver) 

    Presentation date： 2011.12

  • Constructive Understanding of Multicellular Network using On-chip Cellomics

    Kenji Yasuda

    9th International Colloquium on Scanning Probe Microscopy (ICSPM-19)  (Toyako) 

    Presentation date： 2011.12

  • On-chip cellomics for quasi-in vivo drug discovery technology

    Kenji Yasuda

    The 11th US-Japan Symposium on Drug Delivery Systems Conference  (Maui) 

    Presentation date： 2011.12

  • 画像ベースによる収縮力と細胞外電位の同時計測技術の開発

    金子智行, 庄司亨, 野村典正, 南沢享, 安田賢二

    自然科学研究機構 生理学研究所 研究会  (岡崎) 

    Presentation date： 2011.11

  • Development of 1480 nm Photothermal High-Speed Real-Time Polymerase Chain Reaction System for single cell Recognition

    Hideyuki Terazono, Akihiro Hattori, Hiroyuki Takei, Hyonchol Kim, Masahito Hayashi, Kenji Yasuda

    5th International Conference on Analysis of Cells at the Single Cell Level  (Carry-Le-Route) 

    Presentation date： 2011.11

  • オンチップ細胞ネットワーク計測の最前線： On-chip quasi-in vivoモデルによる創薬支援技術の開発

    安田賢二

    東京大学第４回マイクロ・ナノ多機能デバイス研究ネットワークシンポジウム  (東京) 

    Presentation date： 2011.11

  • Algebraic and geometric understanding of cells, epigenetic inheritance of phenotypes between generations using on-chip single cell cultivation system

    Kenji Yasuda

    5th International Conference on Analysis of Microbial Cells at the Single Cell Level  (Carry-Le-Route) 

    Presentation date： 2011.11

  • Imaging Optical System expanded Depth of Field for Direct Observation of Cells in Microfluidics

    Akihiro Hattori, Masahito Hayashi, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Highly Sensitive Detection of Target Biomolecules on a Cell Surface using Metal Nano-particles Conjugated with Aptamer probes

    Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Development of a Constitutive Cell-chip Measurement with Human Cardiomyocytes by using on-chip Cell Multi Electrode Assay

    Tomoyo Hamada, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Minimization of Artifacts in Electrical Stimulation with Extracellular Potential Measurement

    Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Comparison of Micromanipulation Systems using Electrophoresis and Dielectrophoresis by the Upper Limit of Traveling Rate of Microparticles or Cells in Various Solutions

    Masahito Hayashi, Hyonchol Kim, Hideyuki Terazono, Akihiro Hattori, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Quasi-in Vivo Heart Electrocardiogram Measurement using Convolution of Field Potential Propagation in Cardiomyocytes Network Circuit

    Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    24th International Microprocesses and Nanotechnology Conference  (Kyoto) 

    Presentation date： 2011.10

  • Construction and Analysis of an Artificial Neuronal Network Using a Neuron-Collecting, Micro-Patterning Method Based on a Multi-Electrode Array System

    Hideyuki Terazono, Hyonchol Kim, Masahito Hayashi, Akihiro Hattori, Hiroyuki Takei, Kenji Yasuda

    International Conference on Neural Computation Theory and Applications, NCTA2011  (Paris) 

    Presentation date： 2011.10

  • オンチップ細胞ネットワーク計測技術を用いたquasi-in vivo 心毒性予測スクリーニング系の開発

    安田賢二

    日本安全性薬理研究会 第1 回情報交換会  (東京) 

    Presentation date： 2011.10

  • V字型電極アレイを用いた誘電泳動力による微粒子の連続的濃縮分離

    Masahito Hayashi, Hyonchol Kim, Hideyuki Terazono, Akihiro Hattori, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • 非侵襲的な細胞精製に向けた画像認識による神経細胞の同定と測定技術の開発

    Hideyuki Terazono, Masahito Hayashi, Hyonchol Kim, Akihiro Hattori, Tomoyuki Kaneko, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • 生体反応過程を再構成する人工ナノ空間を模した様々なサイズ・元素のヤヌス粒子とカップの作製

    Hyonchol Kim, Hiroyuki Takei, Masahito Hayashi, Hideyuki Terazono, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • オンチップ細胞計測技術を用いた薬剤の心毒性評価システムに開発

    Tomoyo Hamada, Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • Quasi-in vivo heart electrocardiogram measurement using convolution of field potential propagation in cardiomyocyte network circuit

    Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • オンチップ多電極計測システムを用いたヒトES細胞由来心筋細胞塊の細胞外電位計測

    Tomoyuki Kaneko, Fumimasa Nomura, Tomoyo Hamada, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • Construction of an artificial neuronal network and electrophysiological measurement with a selective collection method of cultured primary neurons

    Hideyuki Terazono, Hyonchol Kim, Masahito Hayashi, Akihiro Hattori, Kenji Yasuda

    第34回日本神経科学大会  (横浜) 

    Presentation date： 2011.09

  • 様々な粒径・元素のヤヌス粒子の作製と生体反応計測への応用

    金 賢徹, 竹井弘之, 林 真人, 寺薗英之, 安田賢二

    第72回 応用物理学会学術講演会  (山形) 

    Presentation date： 2011.09

  • 画像認識によるフローサイトメトリーのための被写界深度拡大光学系の開発

    Akihiro Hattori, Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Kenji Yasuda

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • 計測、その他

    安田賢二

    第49回日本生物物理学会年会  (姫路) 

    Presentation date： 2011.09

  • 機能的疑似in-vivoオンチップ細胞ネットワークモデルの構成的構築とその創薬支援応用

    安田賢二

    第84回日本生化学会大会  (京都) 

    Presentation date： 2011.09

  • ES細胞・iPS細胞を用いた薬物心毒性評価

    安田賢二

    第319回CBI学会研究講演会  (東京) 

    Presentation date： 2011.08

  • Constrictive On-Chip Cellomics Technologies for in vitro Cell-Network Drug-Screening System Exploiting Human iPS Cells and Other Pluripotent Stem Cells

    Kenji Yasuda

    Japan Science and Technology Agency(JST), Agency for Science, Technology and Research (A*STAR), Japan-Singapore Joint Workshop on Bioelectronics  (Kyoto) 

    Presentation date： 2011.08

  • Fabrication and application of size-controlled metal nano-cups for indentification of genome/proteome expression profiles

    Hyonchol Kim, Hiroyuki Takei, Masahito Hayashi, Hideyuki Terazono, Kenji Yasuda

    Particles2011  (Berlin) 

    Presentation date： 2011.07

  • iPS細胞等多能性幹細胞を用いた創薬支援技術の最新動向

    安田賢二

    第38回日本トキシコロジー学会学術年会  (東京) 

    Presentation date： 2011.07

  • ヒト幹細胞由来心筋細胞を用いたイオンチャネルタンパクのトラフィッキング解析とそのトキシコロジーへの展開の可能性

    安田賢二

    第38回日本トキシコロジー学会学術年会  (横浜) 

    Presentation date： 2011.07

  • オンチップ・セロミクス技術を用いた1細胞からの後天的情報解析

    安田賢二

    大阪大学大学院 生命機能研究科セミナー  (大阪) 

    Presentation date： 2011.07

  • オンチップ・テクノロジーを用いたCTC計測の最前線

    安田賢二

    第15回日本がん分子標的治療学会学術集会  (東京) 

    Presentation date： 2011.06

  • Human iPS/ES cell technology and its application to toxicology testing, especially focusing on in vitro cardiac function toxicity

    Kenji Yasuda

    2011 HESI Annual Meeting  (Alexandria) 

    Presentation date： 2011.06

  • 多元素金属微粒子プローブセットによるinsitu生体定量計側を目指すアダプティブＳＥＭの開発

    金賢徹, 竹井弘之, 林真人, 寺薗英之, 安田賢二

    日本顕微鏡学会 第67回学術講演会  (福岡) 

    Presentation date： 2011.05

  • On-Chip Cellomics Technology for Constructive Understanding of Deterministic Mechanisms in Higher Complexity of Living Systems

    Kenji Yasuda

    44th Annual Meeting for the Japanese Society of Developmental Biologists (cosponsor: the Asia-Pacific Developmental Biology Network)  (Ginowan) 

    Presentation date： 2011.05

  • Spatiotemporal poincare plotting for torsades de pointes prediction in vitro drug-screening system exploiting human iPS cells and other pluripotent stem cells

    Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 55th Annual Meeting  (Baltimore) 

    Presentation date： 2011.03

  • オンチップ・セロミクス計測：ヒト幹細胞由来心筋細胞を用いた細胞ネットワークからの生命の理解と創薬スクリーニングへの応用展開

    安田賢二

    第10回日本再生医療学会総会  (東京) 

    Presentation date： 2011.03

  • Nanotechnology for On-chip Cellomics Screening

    Kenji Yasuda

    Pittcon Conference&EXPO 2011  (Atlanta) 

    Presentation date： 2011.03

  • ヒトES/iPS 細胞を用いた薬剤の催不整脈性評価技術の開発

    安田賢二

    第２回日本安全性薬理研究会学術年会  (東京) 

    Presentation date： 2011.02

  • 「決定論」は生命システムの高次階層をどこまで説明できるのかー１細胞からの構成的生命システムの理解ー

    安田賢二

    早稲田大学大学院先進理工学研究科 第30回生命医科学科講演会  (東京) 

    Presentation date： 2011.02

  • Entrainment of the beating rhythms of cardiomyocyte network with external electric stimulation

    Tomoyuki Kaneko, Fumimasa Nomura, Yuki Tomoe, Kenji Yasuda

    The American Society for Cell Biology 50th Annual Meeting  (Philadelphia) 

    Presentation date： 2010.12

  • Simultaneous LabeIing of Target Biomolecules using Various Metal Nano-Shell Labels

    Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    The American Society for Cell Biology 50th Annual Meeting  (Philadelphia) 

    Presentation date： 2010.12

  • Reversible Cell Labeling Exploiting Fluorescent Aptamer and Nuclease Digestion

    Hideyuki Terazono, Masahito Hayashi, Hyonchol Kim, Kenji Yasuda

    The American Society for Cell Biology 50th Annual Meeting  (Philadelphia) 

    Presentation date： 2010.12

  • On-chip pre-clinical cardiac toxicity: Testing compounds beyond hERG and QT using hES/hiPS cardiomyocyte re-entry cell network model on a chip

    Kenji Yasuda

    日本学術振興会 未踏・ナノデバイステクノロジー第151委員会 ナノバイオフュージョン分科会 第16回研究会  (東京) 

    Presentation date： 2010.12

  • パネルディスカッション 生物物理、今後の50年：細胞ネットワーク

    安田賢二

    日本生物物理学会 50周年記念講演会  (東京) 

    Presentation date： 2010.12

  • Application of void cap-shaped metal nano-shells as artificial nano-space for biomolecular reactions

    Hyonchol Kim, Masahito Hayashi, Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Kokura) 

    Presentation date： 2010.11

  • On-Chip Multichannel Extracellular Potential Monitoring System for Measurement of Hysteresis of Neural Networks Activity by Electrical stimulation.

    Hideyuki Terazono, Masahito Hayashi, Hyonchol Kim, Akihiro Hattori, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Kokura) 

    Presentation date： 2010.11

  • Continuous Concentration and Separation of Microparticles Depend on Dielectric Constant by using Dielectrophoretic Force in a V-shaped electrode Array

    Masahito Hayashi, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Kokura) 

    Presentation date： 2010.11

  • Image recognition based cell sorting device with cultivation chamber

    Akihiro Hattori, Masahito Hayashi, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Kokura) 

    Presentation date： 2010.11

  • Development of a high-speed real-time PCR system for rapid cancer gene detection

    Hideyuki Terazono, Kim Hyonchol, Masahito Hayashi, Takei Hiroyuki, Akihiro Hattori, Kenji Yasuda

    第4回次世代を担う若手医療薬学会シンポジウム  (東京) 

    Presentation date： 2010.11

  • Development of in vitro drug-screening system exploiting human iPS cells and other pluripotent stem cells

    Kenji Yasuda

    The Swiss-Japanese Meeting on Industrial Use of iPS  (Basel) 

    Presentation date： 2010.11

  • Frontier of single-cell-based on-chip screening assay: from single-cell-based purification to single-cell genome/proteome analysis

    Kenji Yasuda

    NEDO-OSEO Workshop : Industrial application of iPS Cells  (Paris) 

    Presentation date： 2010.11

  • Development of in vitro drug-screenig system exploiting human iPS cells and other pluripotent stem cells

    Kenji Yasuda

    NEDO-OSEO Workshop : Industrial application of iPS Cells  (Paris) 

    Presentation date： 2010.11

  • 早期がん診断を実現するナノバイオ計測技術

    安田賢二

    かわさきサイエンス＆テクノロジーフォーラム2010  (川崎) 

    Presentation date： 2010.11

  • 生物剤検知技術のフロンティア：微量血中がん細胞

    安田賢二

    防衛技術シンポジウム2010  (東京) 

    Presentation date： 2010.11

  • Challenge for simultaneous detection of a lot of biomolecules with high spatial resolution using metal nano-praticle label set and field emission scanning electron microscopy

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    5th International Symposium on Practical Surface Analysis  (Gyeongju) 

    Presentation date： 2010.10

  • On-Chip Pre-Clinical Cardiac Toxicity: Testing Compounds Beyond hERG And QT Using hES/hiPS Cardiomyocyte Re-Entry Cell Network Model On A Chip

    Kenji Yasuda, Tomoyuki Kaneko, Fumimasa Nomura

    The 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences  (Groningen) 

    Presentation date： 2010.10

  • iPS細胞等多能性幹細胞を用いた創薬スクリーニングの新展開

    安田賢二

    BioJapan2010  (横浜) 

    Presentation date： 2010.10

  • iPS細胞からの電気生理学：オンチップ細胞ネットワークモデルの心電学への応用の可能性

    安田賢二

    心電学フロンティア2010-第45回理論心電図研究会  (大分) 

    Presentation date： 2010.10

  • Development of "Multi-Color" Nano-Particle Labeling for Single Cell Molecular Expression Analysis

    Hyonchol Kim, Hideyuki Terazono, Masahito Hayashi, Hiroyuki Takei, Kenji Yasuda

    第48回日本生物物理学会年会  (仙台) 

    Presentation date： 2010.09

  • Labelling of live cells using fluorescent aptamers: binding reversal with DNA nucleases

    Hideyuki Terazono, Yu Anzai, Kenji Yasuda

    第48回日本生物物理学会年会  (仙台) 

    Presentation date： 2010.09

  • Development of cell analysis and separation system by Ultra fast image analysis

    Akihiro Hattori, Masahito Hayashi, Shin'ichi Ishiwata, Kenji Yasuda

    第48回日本生物物理学会年会  (仙台) 

    Presentation date： 2010.09

  • Community effect to the drug sensitivity on geometrical patterned cardiomyocytes network by using On-Chip MEA system

    Fumimasa Nomura, Sachie Ohhara, Tomoyuki Kaneko, Kenji Yasuda

    第48回日本生物物理学会年会  (仙台) 

    Presentation date： 2010.09

  • Community effect of the cardiomyocyte network to the external electrical stimulation

    Tomoyuki Kaneko, Fumimasa Nomura, Yuki Tomoe, Kenji Yasuda

    第48回日本生物物理学会年会  (仙台) 

    Presentation date： 2010.09

  • 中空キャップ状ナノシェルへの生体分子修飾と応用利用の検討

    金賢徹, 林真人, 寺薗英之, 竹井弘之, 安田賢二

    第71回応用物理学会学術講演会  (長崎) 

    Presentation date： 2010.09

  • Image cytometry

    Kenji Yasuda

    The 23rd Annual and International Meeting of the Japanese Association for Animal Cell Technology (JAACT2010)  (Sapporo) 

    Presentation date： 2010.09

  • In vitro preclinical cardiac safety pharmacology: Development of drug proarrhythmic measurement with human embryonic stem cell derived cardiomyocyts network

    Tetsuo Kitamura, Fumimasa Nomura, Tomoyuki Kaneko, Peter Sartipy, Keiichi Fukuda, Atsushi Sugiyama, Masaru Sekijima, Kenji Yasuda

    WorldPharma2010, 16th World Congress on Basic and Clinical Pharmacology  (Copenhagen) 

    Presentation date： 2010.07

  • Analysis of proarrhythmic effects of typical IKr blockers using human ES/iPS cell-derived cardiomyocytes

    Atsushi Sugiyama, Tetsuo Kitamura, Fumimasa Nomura, Tomoyuki Kaneko, Peter Sartipy, Keiichi Fukuda, Kenji Yasuda

    WorldPharma2010, 16th World Congress on Basic and Clinical Pharmacology  (Copenhagen) 

    Presentation date： 2010.07

  • 1細胞からの構成的生命科学：オンチップ・セロミクス計測技術を用いた１細胞からの後天的情報解析とその応用展開

    安田賢二

    (財)生産開発科学研究所 医工学フォーラム  (京都) 

    Presentation date： 2010.07

  • サイトメトリーシステムの未来を考える(2)：CTC技術の最前線・がん転移計測技術と医療応用

    安田賢二

    第20回日本サイトメトリー学会学術集会  (東京) 

    Presentation date： 2010.06

  • CTC計測装置技術の現状と次世代CTC装置技術の展望

    安田賢二

    第20回日本サイトメトリー学会学術集会  (東京) 

    Presentation date： 2010.06

  • オンチップ・セロミクス：チップ上に細胞から臓器機能モデルを作る構成的アプローチ

    安田賢二

    第37回日本トキシコロジー学会学術年会  (沖縄) 

    Presentation date： 2010.06

  • Fast Cell Identification Using On-Chip Technologies for Cancer Research, Diagnosis, and Therapy

    Kenji Yasuda

    BIT's 3rd Annual World Cancer Congress 2010  (Singapore) 

    Presentation date： 2010.06

  • オンチップ・セロミクス技術を用いた心筋細胞ネットワークモデルの構成的構築と1細胞計測技術の開発

    安田賢二

    第37回日本トキシコロジー学会学術年会・ワークショップ iPS細胞等多能性幹細胞を用いた創薬スクリーニングシステムの新展開-新知見からその魅力に迫る-  (沖縄) 

    Presentation date： 2010.06

  • Session :Toxicology

    Kenji Yasuda

    Particle 2010  (Orlando) 

    Presentation date： 2010.05

  • オンチップシステムを用いた細胞ネットワークの再構成：秩序から別の秩序への創発の過程についての考察

    安田賢二

    リズム現象の研究会 V  (東京) 

    Presentation date： 2010.05

  • Production of Size-Controlled Nanoscopic Cap-Shaped Metal Shell Probes for Non-Anplifide Quantitative Single-Cell Genome/Proteome Measurement

    Kenji Yasuda

    Particle 2010  (Orlando) 

    Presentation date： 2010.05

  • Development of an integrated system for rapid detection of biological agents

    Hideyuki Terazono, Hiroyuki Takei, Masahito Hayashi, Akihiro Hattori, Kenji Yasuda

    SPIE Defense, Security, and Sensing 2010  (Orlando) 

    Presentation date： 2010.04

  • Development of a high-speed real-time PCR system for rapid and precise nucleotide recognition

    Hideyuki Terazono, Hiroyuki Takei, Akihiro Hattori, Kenji Yasuda

    SPIE Defense, Security, and Sensing 2010  (Orlando) 

    Presentation date： 2010.04

  • 「新ツール」iPS細胞を用いたQT延長・催不整脈評価

    安田賢二

    第83回日本薬理学会年会 日本トキコロジー学会・日本薬理学会合同シンポジウム「安全性薬理試験の現状と将来」  (大阪) 

    Presentation date： 2010.03

  • Community Effect to the External Electrical Stimulation on Cardiomyocytes by using On-Chip MEA System

    Yuki Tomoe, Tomoyuki Kaneko, Fumimasa Nomura, Kenji Yasuda

    Biophysical Society 54th Annual Meeting  (San Francisco) 

    Presentation date： 2010.02

  • Development of Novel System for the Functional Analysis of the Cardiomyocytes Network Model Using On-Chip Cellomics Technology

    Fumimasa Nomura, Tetsuo Kitamura, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 54th Annual Meeting  (San Francisco) 

    Presentation date： 2010.02

  • Community Effect on Drug Sensitivity of Cardiomyocytes Controlled Spatial Patterns by using On-Chip MEA System

    Sachie Ohhara, Fumimasa Nomura, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 54th Annual Meeting  (San Francisco) 

    Presentation date： 2010.02

  • On-Chip Pre-Clinical Cardiac Toxicity: Testing Compounds Beyond hERG and QT using hES/hiPS Cardiomyocyte Cell Network Re-Entry Model on a Chip

    Kenji Yasuda

    2nd INTERNATIONAL CONFERNCE ON DRUG DISCOVERY & THERAPY  (Dubai) 

    Presentation date： 2010.02

  • Single Event Observation of Sequential Phagocytosis by a Mouse Alveolar Macrophage

    Masahito Hayashi, Kenji Yasuda

    49th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2009.12

  • Development of a High-speed and Automatable Real-time PCR System for Rapid Nucleotide Recognition

    Hideyuki Terazono, Hiroyuki Takei, Akihiro Hattori, Kenji Yasuda

    49th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2009.12

  • Quantitative and Sensitive Detection of Target DNA Using Nano-Particles as Labels

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    49th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2009.12

  • Community Effects in Cardiomyocyte Networks Analyzed with On-Chip Single-Cell Measurement System

    Tomoyuki Kaneko, Fumimasa Nomura, Yuki Tomoe, Kenji Yasuda

    49th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2009.12

  • Micro droplet PCR: Development of high-speed real-time PCR system for rapid and precise nucleotide recognition

    Hideyuki Terazono, Hiroyuki Takei, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Sapporo) 

    Presentation date： 2009.11

  • Production of nano-particles created with several materials for labeling of biological molecules

    Hyonchol Kim, Hiroyuki Takei, Kenji Yasuda

    22nd International Microprocesses and Nanotechnology Conference  (Sapporo) 

    Presentation date： 2009.11

  • A Novel Cell Purification Device based on Fast Image Analysis in Cellomics Era

    Hattori Akihiro, Hayashi Masahito, Yasuda Kenji

    22nd International Microprocesses and Nanotechnology Conference  (Sapporo) 

    Presentation date： 2009.11

  • Reconstructive approach for on-chip tissue/organ model screening system for drug discovery and toxicology

    Kenji Yasuda

    APBioChEC '09  (Kobe) 

    Presentation date： 2009.11

  • 超高速遺伝子増幅技術の 生物剤検知及び検体迅速検査への応用

    安田賢二

    防衛シンポジウム2009  (東京) 

    Presentation date： 2009.11

  • オンチップ多電極電位計測システムを用いたマウス胎仔心筋細胞における細胞外電位の波形解析

    野村典正, 金子智行, 巴悠記, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • 多電極チップを用いた心筋細胞小集団による長期的心毒性評価法の開発

    巴悠記, 金子智行, 野村典正, 高戸珠恵, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • マクロファージによる逐次貪食過程の観察

    林真人, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • 超高速リアルタイムPCR装置を用いた非特異的DNA断片増幅の抑制

    寺薗英之, 竹井弘之, 服部明弘, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • 走査型電子顕微鏡における「多色」標識法

    金賢徹, 竹井弘之, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • 多電極計測システムを用いた心筋細胞ネットワークの集団化効果の理解

    金子智行, 野村典正, 巴悠記, 安田賢二

    第47回日本生物物理学会  (徳島) 

    Presentation date： 2009.10

  • iPS細胞等幹細胞を用いた創薬スクリーニングシステムの開発

    安田賢二

    JBIC２００９  (東京) 

    Presentation date： 2009.10

  • iPS細胞等幹細胞を用いた創薬スクリーニングシステムの開発

    安田賢二

    JBIC２００９  (東京) 

    Presentation date： 2009.10

  • A New In Vitro Model to Detect Proarrhythmic Effects of Drugs on Human Heart Cells

    Atsushi Sugiyama, Tetsuo Kitamura, Fumimasa Nomura, Tomoyuki Kaneko, Yuji Nakamura, Peter Sartipy, Kenji Yasuda

    The 9th Annual Meeting of Safety Pharmacology Society  (Strasbourg) 

    Presentation date： 2009.09

  • 様々な粒径・材質の均質なナノ粒子の作製

    金賢徹, 竹井弘之, 安田賢二

    2009年秋季第70回応用物理学会学術講演会  (札幌) 

    Presentation date： 2009.09

  • オンチップ・セロミクス計測技術を用いた心筋細胞ネットワーク計測

    安田賢二

    第61回 生物工学会 年会 シンポジウム（生物と機械の融合－バイオロボティクス－）  (名古屋) 

    Presentation date： 2009.09

  • 1細胞からの構成的生命科学：オンチップ・セロミクス計測技術を用いた１細胞からの後天的情報解析

    安田賢二

    生物物理若手の会 夏の学校  (千歳) 

    Presentation date： 2009.08

  • オンチップ・セロミクス技術を用いた細胞ネットワーク創薬支援

    安田賢二

    日本薬学会第 129年会シンポジウム 「新しい細胞培養システムの開発とその創薬支援研究への応用」  (京都) 

    Presentation date： 2009.03

  • オンチップ１細胞培養計測システムを用いた１細胞への刺激と応答の解析

    安田賢二

    平成20年度生理学研究所研究会「細胞死研究の多面的、包括的理解に向けて」  (岡崎) 

    Presentation date： 2009.03

  • 心筋細胞ネットワークによる オンチップ・リエントリー・モデルを用いた期外収縮計測技術の開発

    安田賢二

    財団法人 先端医療振興財団 セミナー  (神戸) 

    Presentation date： 2009.02

  • 細胞を用いたオンチップ・センシング・バイオテクノロジー:－細胞からの構成的アプローチによる生命システムの理解と創薬への応用－

    安田賢二

    ナノバイオExpo 2009「iPS細胞技術・再生医療実現を加速するナノバイオ技術」  (東京) 

    Presentation date： 2009.02

  • 構成的神経ネットワークの活動ダイナミクス計測

    鈴木郁郎, 林純子, 安田賢二

    第一回定量生物学の会  (東京) 

    Presentation date： 2009.01

  • オンチップ・リエントリーモデルを用いた期外収縮計測システムによる毒性検査技術の開発 」

    安田賢二

    第8回ヒューマンサイエンス研究資源バンクセミナー  (大阪) 

    Presentation date： 2009.01

  • On-Chip Pre-Clinical Cardiac Toxicity: Testing Compounds Beyond hERG and QT using Cell Network Re-Entry Model on a Chip

    Kenji Yasuda

    ILSI Health and Environmental Sciences Institute Annual HESI Emerging Issues Meeting  (Tuson) 

    Presentation date： 2009.01

  • Production of nanoscopic metal shells particles for universal labeling of biomolecules

    Hyonchol Kim, Hiroyuki Takei, Yasuda Kenji

    5th International Symposium on Surface Science and Nanotechnology  (Tokyo) 

    Presentation date： 2008.12

  • Single-cell level measurement of conduction velocity in cardiomyocytes network

    Kaneko T, Nomura F, Tomoe Y, Suzuki I, Hayashi J, Yasuda K

    48th Annual Meeting of the American Society for Cell Biology  (San Francisco) 

    Presentation date： 2008.12

  • Formation of a Uniform Polyurea Thin Film by Vapor Deposition Polymerization for Homogeneous Immobilization of DNA

    Kira Atsushi, Hyonchol Kim, Yasuda Kenji

    5th International Symposium on Surface Science and Nanotechnology  (Tokyo) 

    Presentation date： 2008.12

  • Development of a pulsed light source for fast capturing microscopy using higi-intensity LED

    服部明弘, 林真人, 安田賢二

    日本生物物理学会第46回年会  (福岡) 

    Presentation date： 2008.12

  • On-chip concentration of isolated cells uising particles focusing with V-shape arranged micropillars

    林真人, 安田賢二

    日本生物物理学会第46回年会  (福岡) 

    Presentation date： 2008.12

  • 様々な粒径・元素ナノ粒子プローブセットで標識された標的ＤＮＡの無増幅定量検出法の開発

    金賢徹, 竹井弘之, 安田賢二

    日本生物物理学会第46回年会  (福岡) 

    Presentation date： 2008.12

  • オンチップ・アガロースマイクロチャンバー内での細胞数を制御した心筋細胞集団の拍動ゆらぎの計測

    Yuki Tomoe, Tomoyuki Kaneko, Fumimasa Nomura, Junko Hayashi, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • アガロースマイクロ加工技術を用いた制御空間内での１神経細胞レベル軸索・樹状突起の伸長ダイナミクス解析

    Sachie Ohhara, Ikurou Suzuki, Junko Hayashi, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • 画像認識型セルソーティングシステムの開発（２）; 細胞イメージのための被写界深度と分解能の改良

    Tomonari Kouguchi, Masahito Hayashi, Yoshie Kawase, Akihiro Hattori, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • オンチップ心筋ネットワークにおける細胞外電位の異方性伝導

    Fumimasa Nomura, Tomoyuki Kaneko, Junko Hayashi, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • 高速リアルタイムPCR装置を用いたDNAポリメラーゼ伸長速度の測定

    Hideyuki Terazono, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • 2神経細胞の自発活動ダイナミクス

    Ikurou Suzuki, Junko Hayashi, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • 細胞ネットワークモデルのための一細胞レベルでの心筋細胞伝導速度の測定

    Tomoyuki Kaneko, Fumimasa Nomura, Yuki Tomoe, Ikurou Suzuki, Junko Hayashi, Kenji Yasuda

    第46回日本生物物理学会  (福岡) 

    Presentation date： 2008.12

  • 走査型電子顕微鏡観察用金属ラベル：元素別識別方法

    竹井弘之, 金賢徹, 安田賢二

    日本生物物理学会第46回年会  (福岡) 

    Presentation date： 2008.12

  • オンチップ・セロミクス技術 を用いた創薬支援・基礎医学研究の展開

    安田賢二

    分子生物・生化学会合同年会(BMB2008) シンポジウム：ナノバイオテクノロジーの新展開  (神戸) 

    Presentation date： 2008.12

  • 1細胞からのセンシングバイオロジー：オンチップ計測システムを用いた細胞ネットワーク・センシングシステムの構成的構築とその創薬支援への応用

    安田賢二

    第5回IBBシンポジウム（センシングバイオロジー）  (東京) 

    Presentation date： 2008.12

  • オンチップ技術を用いた細胞分子センシング

    安田賢二

    全日本科学機器展 in 東京2008、第62回次世代センサセミナーシリーズ「新規バイオセンシング研究及びデバイス機器開発  (東京) 

    Presentation date： 2008.11

  • 心筋細胞ネットワークによるオンチップ・リエントリー・モデルを用いた期外収縮計測技術の開発

    安田賢二

    平成20年度 生理研研究会「イオンチャネル・トランスポーターと心血管機能：学際的取り組みによる新戦略」  (岡崎) 

    Presentation date： 2008.11

  • オンチップ・セロミクス計測系を用いた細胞からの生命システム理解の構成的アプローチ

    安田賢二

    バイオマテリアル学会：診断・センシングマテリアルセッション  (東京) 

    Presentation date： 2008.11

  • 光学的セルソーター技術の 微生物識別分取への応用

    安田賢二

    防衛技術シンポジウム 2008  (東京) 

    Presentation date： 2008.11

  • オンチップ・セロミクス計測システム

    安田賢二

    第26回医用高分子研究会講座『検査・診断を支える高分子』  (東京) 

    Presentation date： 2008.11

  • Universal Method for Forming Various Metal Particles as Multiplexed Labels for Electoron Microscopy in the Backscattering Mode

    Hiroyuki Takei, Hyonchol Kim, Yasuda Kenji

    American Vacuum Society  (Boston) 

    Presentation date： 2008.10

  • Focusing of Microparticles in a Microfluidic Channel with V-shape Arranged Micropillars

    Hayashi M, Yasuda K

    21st International Microprocesses and Nanotechnology Conference  (Fukuoka) 

    Presentation date： 2008.10

  • High sensitive detection of target DNA using a set of gold nano-particle labels

    Hyonchol Kim, Hiroyuki Takei, Yasuda Kenji

    21nd International Microprocesses and Nanotechnology Conference（MNC2008)  (Fukuoka) 

    Presentation date： 2008.10

  • オンチップ心毒性検査技術：hERG計測、ＱＴ延長計測に続く候補物質検査方法

    安田賢二

    BioJapan 2008  (横浜) 

    Presentation date： 2008.10

  • 生体分子標識のための様々な元素ナノシェル粒子の作成と識別

    金賢徹, 竹井弘之, 安田賢二

    第69回応用物理学会学術講演会  (春日井) 

    Presentation date： 2008.09

  • Detection of spontaneous firing pattern in cultured single neuron: application of a multi-electrode array chip combined with agarose microstructures

    Suzuki I, Hayashi J, Yasuda K

    6th International Meeting on Substrate-Integrated Micro Electrode Arrays  (Reutlingen) 

    Presentation date： 2008.07

  • 個々の細胞の個性を診断する計測方法の開発

    金賢徹, 長田俊哉, 猪飼篤, 安田賢二

    ナノバイオ若手ネットワーキングシンポジウム Yong NanoBio  (静岡) 

    Presentation date： 2008.06

  • 細胞ベース創薬支援技術：無修飾細胞利用のための画像ベース細胞識別に挑む アプタマーへの期待

    安田賢二

    第18回日本サイトメトリー学会シンポジウム（サイトメトリーシステムの未来を考える（１）アプタマーは抗体を超えるのか？  (東京) 

    Presentation date： 2008.06

  • オンチップ・セロミクス技術を用いた創薬支援・基礎医学研究

    安田賢二

    東京医科歯科大学大学院生命情報科学教育部「病気に挑む生命科学」公開シンポジウム  (東京) 

    Presentation date： 2008.06

  • オンチップ・セロミクス計測技術

    安田賢二

    第１回医工技術研究会, 大田区産業振興協会  (東京) 

    Presentation date： 2008.03

  • Delay Time of the Action Potential in Two Cardiomyocytes Connected by Fibroblasts.

    Kaneko T, Suzuki I, Ando K, Nomura F, Kitamura T, Hayashi J, Yasuda K

    47th Annual Meeting of the American Society for Cell Biology  (Washington D.C.) 

    Presentation date： 2007.12

  • オンチップ1 細胞システムを用いたマクロファージの貪食ダイナミクスの測定

    川瀬芳恵, 松村和典, 石渡信一, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • コラーゲントンネルを用いた血液脳関門モデルの構築

    柴田克也, 寺薗英之, 服部明弘, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 1細胞ベースでの in vitro心筋毒性検査技術の開発

    北村哲生, 野村典正, 林純子, 安東賢太郎, 金子智行, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 線維芽細胞を介した心筋2細胞間電位変化における伝導遅延時間測定

    金子智行, 鈴木郁郎, 安東賢太郎, 野村典正, 北村哲生, 林純子, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 心筋リエントリーネットワークのオンチップ構成的機能再構築

    野村典正, 北村哲生, 林純子, 安東賢太郎, 金子智行, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • マウス心筋細胞拍動能に対するHERG channel の作用

    安東賢太郎, 金子智行, 野村典正, 鈴木郁郎, 北村哲生, 林純子, 松井等, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • レーザ照射アポトーシス誘導による細胞精製技術の開発

    服部明弘, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 高サンプル流速下における画像認識型セルソーターの性能改善

    林真人, 高口智成, 川瀬芳恵, 服部明弘, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 微細加工技術を用いたオンチップ多種細胞同時精製システムの開発

    高口智成, 林真人, 川瀬芳恵, 服部明弘, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • 微量液滴を用いた高速リアルタイムPCR 法の開発

    寺薗英之, 服部明弘, 林真人, 竹井弘之, 武田一男, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • アガロースマイクロ構造内に培養した神経１細胞の長期活動計測

    鈴木郁郎, 林純子, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • アプタマーを用いた可逆的標識による細胞分離技術の開発

    安西悠, 寺薗英之, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • オンチップ1 細胞培養システムを用いた大腸菌の1 次元運動解析

    綾野賢, 梅原千慶, 服部明弘, 安田賢二

    第45回日本生物物理学会年会  (横浜) 

    Presentation date： 2007.12

  • Reconstructive approach for on-chip tissue/organ model screening optical-/electric-monitoring system for drug discovery and toxicology

    Kenji Yasuda

    SPIE Microelectronics, MEMS, and Nanotechnology 2007  (Canberra) 

    Presentation date： 2007.12

  • Quantitative observation of membrane-attached bio-molecules on a cell surface using gold nano-particle and atomic force microscopy.

    Kim H, Oikawa K, Yasuda K

    20th International Microprocesses and Nanotechnology Conference 2007  (Kyoto) 

    Presentation date： 2007.11

  • Rapid real-time PCR-based nucleotide sequence measurement method using 1480nm infrared laser heating.

    Terazono H, Hattori A, Takei H, Takeda K, Yasuda K

    20th International Microprocesses and Nanotechnology Conference 2007  (Kyoto) 

    Presentation date： 2007.11

  • Collagen micro flow channel for in vitro Blood-Brain Barrier model.

    Shibata K, Terazono H, Hattori A, Yasuda K

    20th International Microprocesses and Nanotechnology Conference 2007  (Kyoto) 

    Presentation date： 2007.11

  • 1細胞からの生命科学－オンチップ・セロミクス計測を用いた生命システムの後天的情報の理解とその応用

    安田賢二

    第4回コンビナトリアル・バイオエンジニアリング会議  (大阪) 

    Presentation date： 2007.11

  • 細胞から再構築した神経ネットワーク－1細胞からの生命科学－

    安田賢二

    平成19年度物理学会公開講座「物理が解き明かす脳のひみつ」  (東京) 

    Presentation date： 2007.10

  • 元素組成比を高精度制御したアロイナノ粒子の作製

    金賢徹, 竹井弘之, 安田賢二

    2007年秋季第68回応用物理学会学術講演会  (北海道) 

    Presentation date： 2007.09

  • 1細胞からの生命科学－オンチップ・セロミクス計測を用いた生命システムの後天的情報の理解とその応用

    安田賢二

    平成19年度第1回東工大バイオ計測研究会 「バイオチップ最前線」  (町田) 

    Presentation date： 2007.09

  • 1細胞からの構成的生命科学－薬物・医療スクリーニングを目指したオンチップ組織・臓器モデル計測評価系の開発

    安田賢二

    ゲノム創薬フォーラムキーテクノロジー2007  (東京) 

    Presentation date： 2007.09

  • Identification of cell phenotypes with quantitative evaluation of expressed biomolecules on a cell surface using a set of nano-particle markers.

    Kim H, Kawase Y, Oikawa K, Akiyoshi K, Yasuda K

    Jeju2007, Scanning Probe Microscopy, Sensors and Nanostructures  (Jeju) 

    Presentation date： 2007.06

  • 1細胞からの生命科学－生命の安全・安心を細胞から理解する

    安田賢二

    如水会第65期フォーラム－安全と安心の未来をさぐる  (東京) 

    Presentation date： 2007.06

  • 1細胞からの構成的生命科学－薬物・医療スクリーニングを目指したオンチップ組織・臓器モデルの構築とその応用

    安田賢二

    北海道大学公開講演会  (札幌) 

    Presentation date： 2007.06

  • 1細胞からの構成的生命科学－薬物・医療スクリーニングを目指したオンチップ臓器モデル構築・計測技術の開発

    安田賢二

    NEDOワークショップ「ターゲット遺伝子探索の新技術 ―遺伝子の森から創薬を見る―」  (東京) 

    Presentation date： 2007.05

  • マイクロデバイス工学とモデル細胞ネットワークを用いた創薬と安全性試験への活用技術の開発

    安田賢二

    第6回日本再生医療学会総会  (横浜) 

    Presentation date： 2007.03

  • Controlling the directions of an axon and dendrites growth using stepwise photo-thermal etching methods.

    Suzuki I, Yasuda K

    The 10th Membrane Research Forum  (Kyoto) 

    Presentation date： 2007.02

  • Hysteresis of phagocytosis process after a series of antigen stimulation in shingle macrophages analyzed by on-chip single cell cultivation system.

    Kawase Y, Matsumura K, Yasuda K

    The 10th Membrane Research Forum  (Kyoto) 

    Presentation date： 2007.02

  • On-chip single cell-based analysis of phagocytosis hysteresis stored in macrophage after a series of spot stimulation by antigens

    Kenji Yasuda

    The 10th Membrane Research Forum  (Kyoto) 

    Presentation date： 2007.02

  • 医療・ライフサイエンス領域におけるナノ計測ニーズ

    安田賢二

    ＪＳＴナノ計測シンポジウム  (千葉) 

    Presentation date： 2007.01

  • Measurement of the field potential in individual cardiomyocytes by multi-electrode array with agarose microchambers.

    Kaneko T, Kojima K, Suzuki I, Sugio Y, Yasuda K

    45th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2006.12

  • Measurement of the field potential in individual cardiomyocytes by multi-electrode array with agarose microchambers

    Tomoyuki Kaneko, Kensuke Kojima, Ikurou Suzuki, Yoshihiro Sugio, Kenji Yasuda

    46th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2006.12

  • Development of simple cell separation method exploiting aptamer-conjugated magnetic microbeads and nuclease digestion.

    Anzai Y, Terazono H, Yasuda K

    45th Annual Meeting of the American Society for Cell Biology  (San Diego) 

    Presentation date： 2006.12

  • On-chip single-cell-based analysis system for drug discovery.

    Kenji Yasuda

    Nanobio Tokyo 2006  (Tokyo) 

    Presentation date： 2006.12

  • Controlling neurite differentiation by single cell neurite’s elongation pattern and length using agarose micro chamber method.

    Kitamura T, Suzuki I, Kaneko T, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Measurement of Community Effect of Cardiomyocytes Estimated by Cell-number Dependency of Beat-Rate Fluctuation Decrease.

    Kojima K, Kaneko T, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Individual-cell-based measurement of the field potential in a cardiomyocyte by multi-electrode array with agarose microchambers.

    Kaneko T, Kojima K, Suzuki I, Sugio Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Single-cell-based-observation of macrophage’s phagocytic responses and alteration of its morphology by activation.

    Shindoh H, Matsumura K, Ishimoto H, Yanagihira K, Kohno S, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Single cell based analysis on the polarity of Escherichia coli cells.

    Ayano S, Inoue I, Shiomi D, Kawagishi I, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Development of a novel cell sorting system based on image recognition and microfabrication technology (III): On-chip cell re-cultivation.

    Terazono H, Hattori A, Kawase Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Development of a novel cell sorting system based on image recognition and microfabrication technology (II): analysis based cell separation.

    Kawase Y, Hattori A, Terazono H, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Development of a novel cell sorting system based on image recognition and microfabrication technology (I): System development.

    Hattori A, Terazono H, Kawase Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Coordination of cell growth and cell cycle progression in green algae.

    Matsumura K, Yagi T, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Physiochemical characterization of nanopipette electrodes for developing real-time in vivo biosensors.

    Umehara S, Karhanek M, Davis RW, Yasuda K, Pourmand N

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan,  (Okinawa) 

    Presentation date： 2006.11

  • Cell characterization method based on transport ability of fluorescent substrate.

    Anzai Y, Moriguchi H, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan,  (Okinawa) 

    Presentation date： 2006.11

  • Plasticity in Single-Cell-Based Reconstructed Neuronal Network Pattern.

    Suzuki I, Hattori A, Jimbo Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Quantification of sizes of gold nano-particles on a cell surface by using curvature-reconstruction- method of the atomic force microscopy.

    Kim H, Oikawa K, Watanabe N, Shigeno M, Shirakawabe Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • Study of Cellular Communication of Suprachiasmatic Nucleus through Synaptic Connections.

    Sugio Y, Terazono H, Suzuki I, Hattori A, Kaneko T, Jimbo Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan  (Okinawa) 

    Presentation date： 2006.11

  • On-chip regulation of neural stem cell differentiation.

    Shibata K, Suzuki I, Terazono H, Sugio Y, Yasuda K

    5th East Asian Biophysics Symposium and 44th Annual Meeting of the Biophysical Society of Japan,  (Okinawa) 

    Presentation date： 2006.11

  • バイオマテリアルから生命システムへ：－１細胞からの生命システム－

    安田賢二

    第28回日本バイオマテリアル学会大会  (東京) 

    Presentation date： 2006.11

  • 1細胞からの構成的生命科学：薬物・医療スクリーニングを目指したオンチップ組織・臓器モデル計測技術の開発

    安田賢二

    第6回JST-SENTANシンポジウム  (東京) 

    Presentation date： 2006.11

  • On-chip single-cell-based tissue/organ model analysis: newly developed reconstructive approach for artificial tissue/organ re-formation.

    Kenji Yasuda

    The 3rd International Symposium on Bioprinting & Biofabrication  (Kanazawa) 

    Presentation date： 2006.11

  • On-Chip Cellomics Assay: Artificial Re-Construction of Tissue Model for Cell Based Drug Discovery.

    Kenji Yasuda

    The 10th International Conference on Miniaturized Systems for Chemistry and Life Sciences (?TAS2006)  (Tokyo) 

    Presentation date： 2006.11

  • Single-molecule-level detection of target genes by using a set of gold nano-particle probes.

    Kim H, Kira Atsushi, Okano K, Yasuda K

    19th International Microprocesses and Nanotechnology Conference 2006  (Kamakura) 

    Presentation date： 2006.10

  • Extracellular Recordings from Artificially Constructed Single-Cell Based Neuronal Networks using Agarose Microchamber Array and Multi-Electrode-Array system.

    Suzuki I, Hattori A, Jimbo Y, Yasuda K

    36th Annual Meeting of Society for Neuroscience  (Atlanta) 

    Presentation date： 2006.10

  • Effect of Tetanic Stimulation in Single-Cell-Based Reconstructed Neuronal Network Pattern.

    Suzuki I, Hattori A, Jimbo Y, Yasuda K

    19th International Microprocesses and Nanotechnology Conference 2006  (Kamakura) 

    Presentation date： 2006.10

  • 1細胞からの生命科学、生命の安全・安心を細胞から理解する

    安田賢二

    東京４大学連合文化講演会「安全と安心の未来をさぐる」  (東京) 

    Presentation date： 2006.10

  • 単一神経細胞から再構築したオンチップ・神経ネットワーク

    安田賢二

    第15回日本バイオイメージング学会学術集会  (盛岡) 

    Presentation date： 2006.10

  • On-chip Single-Cell-Based Tissue/Organ Model Analysis: Newly Developed Reconstructive Approach for Artificial Tissue/Organ Re-Formation.

    Kenji Yasuda

    World Congress on Medical Physics and Biomedical Engineering 2006  (Seoul) 

    Presentation date： 2006.08

  • Electrophysiological Measurement of Artificially Constructed Single-Cell Based Neuronal Networks using Agarose Microchamber Array and 8?m-diameter Multi-Electrode-Array system.

    Suzuki I, Hattori A, Jimbo Y, Yasuda K

    第29回日本神経科学会，  (京都) 

    Presentation date： 2006.07

  • 「オンチップ１細胞ソーティング技術の開発と構成的1細胞培養計測技術への展開」―チップ上に再構成した臓器モデルはDrug Discoveryのモデルとなるか―

    安田賢二

    第16回日本サイトメトリー学会学術集会  (長崎) 

    Presentation date： 2006.07

  • Quantitative evaluation of sizes of nanospheres on a rough surface by using curvature-reconstruction- method of the atomic force microscopy.

    Oikawa K, Kim H, Watanabe N, Shigeno M, Shirakawabe Y, Yasuda K

    Montpellier2006, Scanning Probe Microscopy, Sensors and Nanostructures, Montpellier  (France) 

    Presentation date： 2006.06

  • On-chip single cell based analysis: newly developed reconstructive approach for artificial tissue/organ formation.

    Kenji Yasuda

    20th IUBMB International Congress of Biochemistry and Molecular Biology and 11th FAOBMB Congress  (Kyoto, Japan) 

    Presentation date： 2006.06

  • １細胞から生命システムを創る

    安田賢二

    「東京大学の生命科学」シンポジウム  (東京) 

    Presentation date： 2006.04

  • On-Chip Cell-Network Analysis System for Drug Discovery Technology

    安田賢二

    「日経バイオテクビジネスレビュー」創刊記念セミナー  (東京) 

    Presentation date： 2006.03

  • Adaptation and Inheritance of Epigenetic Information Stored on The Cell Membranes, Components and Their Geometric Localizations.

    Kenji Yasuda

    The 9th Membrane Research Forum  (Kyoto) 

    Presentation date： 2006.03

  • Differential analysis of phenotypical cell characterization exploiting transporter activity measurement with fluorescent substrates.

    Anzai Y, Hattori A, Okano K, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Modeling of cell cycle control in Chlamydomonas.

    Matsumura K, Yagi T, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Single-cell-based-observation of macrophage's phagocytic responses and its processing of the information caused by the multiple-site-specific stimulation.

    Shindou H, Orita K, Matsumura K, Wakamoto Y, Ishimoto H, Yanagihara K, Kohno S, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Examination of optimum shapes of microfluidic devices for cell passage using three-dimensional control of microfluidic pathway.

    Hattori A, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • On-chip control of regulation process of neural stem cell differentiation.

    Shibata K, Suzuki I, Sugio Y, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Controlling the differentiation of axon and dendrite for single cell patterning using agarose photo-thermal etching methods.

    Kitamura T, Suzuki I, Sugio Y, Shibata K, Kaneko T, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Inheritance of epigenetic information stored in cell shape revealed by the single cell-based direct observation.

    Wakamoto Y, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Development of the nanopipette biosensor.

    Umehara S, Pourmand N, Davis RW, Yasuda K, Karhanek M

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Minimum Requirement for Expressing Circadian Rhythm Using Constitutive and Analytical Approach to Suprachiasmatic Nucleus.

    Sugio Y, Terazono H, Suzuki I, Kaneko T, Jimbo Y, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Characterization of the radius of nanospheres by using atomic force microscopy.

    Oikawa K, Kim H, Kira Atsushi, Okano K, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Electrophysiological Measurement of Artificially Constructed Single-Cell Based Neuronal Networks using Agarose Microchamber Array and 8?m Multi-Electrode-Array system.

    Suzuki I, Hattori A, Jimbo Y, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Quantitative evaluation of polyurea thin film method by vapor deposition polymerization for formation of uniformly arranged even interval reactive substrates on DNA chip.

    Kira Atsushi, Kim H, Okano K, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Single-molecule-level gene expression analysis in individual cells using a set of gold nano-particle- probes.

    Kim H, Kira Atsushi, Oikawa K, Okano K, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • Continuous Observation of Single Neurite Extension and Retraction during Differentiation of Micropatterned PC12 Cells in Agarose Microchannels fabricated by Photothermal Etching Method.

    Moriguchi H, Kaneko T, Yasuda K

    50th Annual Meeting of Biophysical Society  (Salt Lake City) 

    Presentation date： 2006.02

  • オンチップ・セロミクス技術を用いた生命システムの後天的情報保持・伝承メカニズムの解明

    安田賢二

    埼玉大学重点研究テーマ「情報生物学の構成的展開」一般公開シンポジウム  (さいたま) 

    Presentation date： 2006.02

  • 生命システムの学習と記憶、淘汰と順応

    安田賢二

    高校生のための金曜特別講座  (東京) 

    Presentation date： 2006.01

  • Synchronization of the beating of the cardiomyocytes by the heterologous cells with the agarose microchamber system

    T. Kaneko, K. Kojima, K. Yasuda

    45th Annual Meeting of the American Society for Cell Biology  (San Francisco) 

    Presentation date： 2005.12

  • Photothermal Etching of Agarose-gel Microstructures for the Topographical Control of Cultured Cells

    Hiroyuki Moriguchi, Kensuke Kojima, Ikurou Suzuki Akihiro Hattori Tomoyuki Kaneko, Kenji Yasuda

    International Symposium on Surface Science and Nanotechnology (ISSS-4)  (Omiya) 

    Presentation date： 2005.11

  • １細胞レベル微小多電極アレイ計測システムの開発とそれを用いた構成的神経回路網の活動計測

    鈴木郁郎, 服部明弘, 杉尾嘉宏, 神保泰彦, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 単一神経細胞の軸索・樹状突起の段階的伸長方向制御とその電気生理学的解析

    北村哲生, 鈴木郁郎, 杉尾嘉宏, 柴田克也, 金子智行, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • マイクロ流体デバイスにおける微細加工技術を用いた細胞整列化のための最適流路形状の検討

    服部明弘, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 大腸菌1細胞における個性創出タイミングの検出

    梅原千慶, 服部明弘, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • マウス心筋幹細胞の単離・培養技術と分化制御技術の検討

    川崎藍, 小島健介, 金子智行, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • マクロファージ1細胞の抗原刺激応答解析(II) 1細胞内における情報処理メカニズムの解析

    折田一樹, 進藤浩史, 松村和典, 若本祐一, 石本裕士, 柳原克紀, 河野茂, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 視交叉上核のリズム発振機構の構成的および分析的研究手法の開発

    杉尾嘉宏, 寺薗英之, 鈴木郁郎, 金子智行, 神保泰彦, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • マクロファージ１細胞の抗原刺激応答解析(I) 抗原刺激解析系の開発

    進藤浩史, 折田一樹, 松村和典, 若本祐一, 石本裕士, 柳原克紀, 河野茂, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • ハイドロゲルの微細加工技術を用いたトポグラフィー制御培養下の細胞形態変化ダイナミクスの構成的研究

    森口裕之, 金子智行, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • クラミドモナス細胞周期制御モデルの検討

    松村和典, 八木俊樹, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 心筋細胞をモデルとした細胞ネットワークの空間パターンとコミュニティ・エフェクトの定量解析

    小島健介, 金子智行, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 同一遺伝型大腸菌の一定環境下での表現型多様性が環境変化時に果たす役割の検討

    若本祐一, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 神経幹細胞のオンチップ培養による神経細胞分化制御及び継代による形質変化の計測

    柴田克也, 鈴木郁郎, 杉尾嘉宏, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 心筋細胞の拍動同期とその制御

    金子智行, 小島健介, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 金微粒子を用いた一細胞レベルでの超微量発現遺伝子定量解析法

    金賢徹, 吉良敦史, 河野博信, 松村和典, 折田一樹, 老川康大, 岡野和宣, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 均一なプローブ固定化用表面としての蒸着重合によるポリ尿素膜の評価

    吉良敦史, 金賢徹, 岡野和宣, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 金ナノ粒子へのSH-ssDNA修飾法とその評価

    河野博信, 吉良敦史, 金賢徹, 岡野和宣, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 蛍光標識物質のトランスポーター通過能を利用した細胞種識別・分離技術の開発

    安西悠, 服部明弘, 岡野和宣, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 大腸菌の細胞分裂によって生じる極性の1細胞計測

    綾野賢, 井之上一平, 塩見大輔, 川岸郁朗, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • AFMを用いた柔らかい試料上での微粒子サイズ定量法

    老川康大, 金賢徹, 吉良敦史, 岡野和宣, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • 心筋細胞の拍動同期とその制御

    金子智行, 小島健介, 安田賢二

    第43回日本生物物理学会年会  (札幌) 

    Presentation date： 2005.11

  • Using agarose microchamber system, measurements of community effects of the cardiomyocytes and the heterogeneous cell types

    Tomoyuki KANEKO, Kensuke KOJIMA, Kenji YASUDA

    The 6th International Conference on Intelligent Materials and Systems ICIM’05  (Tokyo) 

    Presentation date： 2005.07

  • ドラッグスクリーニングのための心筋拍動細胞ネットワークの構築

    安田賢二

    第21回日本DDS学会  (長崎) 

    Presentation date： 2005.07

  • Constructional approach to the morphological functions of multicellular systems using living cells and hydrogel microstructures

    H. Moriguchi, A. Hattori, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Stepwise pattern modification during cultivation using an Stepwise Agar-based On-chip Cell Cultivation system

    Y. Sugio, I. Suzuki, T. Kaneko, Y. Jimbo, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Electorophysiological measurement of neural tissue networks connected by nerve single cells on the chip

    K. Shibata, I. Suzuki, Y. Sugio, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Measurement of Community Effect of Cardiac Myocytes Estimated by Cell-number Dependency of Beating Rhythm Fluctuation Decrease

    K. Kojima, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Cell culture and purification of the selected cells on close-packed microsphere-monolayer

    Y. Anzai, H. Moriguchi, A. Hattori, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Analysis of the dynamics of a-neurite-elongation using the single-cell cultivation system

    C. Lee, I. Suzuki, Y. Sugio, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Station for Integrated Sciences, The Second International Symposium "Life as a Complex System:Constructive and Dynamic Approach to Cell and Developmental Biology"  (Tokyo) 

    Presentation date： 2005.05

  • Electrophysiological Measurement of an Artificially Constructed Neuronal Network pattern by Single Cell

    Ikurou Suzuki, Yoshihiro Sugio, Yasuhiko Jimbo, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Emergence of Individuality in Isolated Single Bacterial Cells Detected by Real-Time Growth/Motility Dual Recording on a Chip

    Senkei Umehara, Akihiro Hattori, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • On-chip single cell based high-speed medium-exchange method using laminar flow and centrifugal force.

    Kazuki Orita, Akihiro Hattori, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Interaction of two cell cycle control mechanisms in Chlamydomonas

    Kazunori Matsumura, Toshiki Yagi, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Observation of yeast prion dynamics using an on-chip single-cell cultivation system

    Satoru Ayano, Shigeko Noma, Masasuke Yoshida, Hideki Taguchi, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Simultaneous measurement of movement and growth of swimming bacterium using on-chip single-cell cultivation assay.

    Akihiro Hattori, Senkei Umehara, Yuichi Wakamoto, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Measurement of Community Effect of Cardiac Myocytes Estimated by Cell-number Dependency of Beat-Rate Fluctuation Decrease using On-Chip Single-Cell Cultivation System

    Kensuke Kojima, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Cell culture and purification of the selected cells on close-packed microsphere-monolayer

    Yu Anzai, Hiroyuki Moriguchi, Akihiro Hattori, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Molecular dynamics of adaptation process of Escherichia coli to aspartic acid concentration changes

    Ippei Inoue, Satoru Ayano, Yuichi Wakamoto, Daisuke Shiomi, Ikuro Kawagishi, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Phenomenological analysis of inheritance of epigenetic information in bacteria using on-chip single-cell cultivation system

    Yuichi Wakamoto, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Development of mRNA Analysis System in Single Living Cells by Atomic Force Microscopy

    Hyonchol Kim, Kazunori Okano, Toshiya Osada, Atsushi Ikai, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Mechanical Instability of Sarcomeres against Ramp Stretch in Spontaneous Oscillatory Contraction of Skeletal Myofibrils

    Yuta Shimamoto, Madoka Suzuki, Kenji Yasuda, Shin'ichi Ishiwata

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Development of hydogel microfabrication techniques as experimental methods for constructional approach to the morphological functions of multicellular systems

    H. Moriguchi, A. Hattori, T. Kaneko, K. Yasuda

    Biophysical Society 49th Annual Meeting  (Long Beach) 

    Presentation date： 2005.02

  • Electorophysiological measurement of neural-tissue-block networks connected by single neurons on the chip

    Katsuya Shibata, Ikurou Suzuki, Yoshihiro Sugio, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 49th Annual meeting  (Long Beach) 

    Presentation date： 2005.02

  • Control of the Intercellular Communication of the heterogeneous Cell types by Cell-based flexible Connecting Method Using agarose Microchamber system

    T. Kaneko, K. Kojima, K. Yasuda

    44th Annual Meeting of the American Society for Cell Biology  (Washington, DC) 

    Presentation date： 2004.12

  • オンチップ一細胞培養系を用いた遊泳細胞の成長および運動の同時計測

    服部明弘, 梅原千慶, 若本祐一, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 大腸菌1細胞でのエネルギー代謝の定量的解析の試み

    梅原千慶, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 筋収縮系自励振動（SPOC）における外力刺激応答のサルコメア長依存性

    島本勇太, 鈴木団, 安田賢二, 石渡信一

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 微細流路での層流現象と遠心力を利用した細胞環境置換法の開発

    折田一樹, 服部明弘, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 哺乳類におけるサーカディアンリズム中枢・視交叉上核の神経細胞の1細胞活動電位計測系の開発

    杉尾嘉宏, 寺薗英之, 鈴木郁郎, 金子智行, 中嶋幹郎, 佐々木均, 神保泰彦, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 培養細胞の形態制御法としてのアガロースゲル微細加工技術の開発

    森口裕之, 服部明弘, 金子智行, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • クラミドモナスに共存する二つの細胞周期制御機構の相互関係

    松村和典, 八木俊樹, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 培養心筋細胞を用いた細胞ネットワークの機能解析

    小島健介, 金子 智行, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 大腸菌の成長静止期培養液に対する応答の1細胞解析

    若本祐一, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 神経組織片と神経１細胞によって形成したネットワークの電気生理学的計測

    柴田克也, 杉尾嘉宏, 鈴木郁郎, 金子智行, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 興奮性・非興奮性細胞を用いた心筋細胞の拍動同期制御

    金子智行, 小島健介, 鈴木郁郎, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 遺伝子発現量の定量的解析を目指したプローブ作製の検討

    金賢徹, 岡野和宣, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 単一生細胞内mRNAの経時計測法の改良

    河野博信, 金賢徹, 鈴木郁郎, 岡野和宣, 長田俊哉, 猪飼篤, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 基板表面での2本鎖DNAの熱変性特性の定量的解析

    岡野和宣, 折田一樹, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 化学刺激に対する大腸菌アスパラギン受容体の分子ダイナミクスと運動ダイナミクスの1細胞計測

    井之上一平, 塩見大輔, 川岸郁朗, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • アガロース薄層に固定したマイクロビーズ上での細胞培養と選択的細胞回収技術の開発

    安西悠, 森口裕之, 服部明弘, 金子智行, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 酵母プリオンタンパク質の1細胞内ダイナミクスの解析

    綾野賢, 野間繁子, 吉田賢右, 田口英樹, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • 構成的アプローチによる神経ネットワークの電気生理学的計測

    鈴木郁郎, 杉尾嘉宏, 金子智行, 神保泰彦, 安田賢二

    第42回日本生物物理学会年会  (京都) 

    Presentation date： 2004.12

  • Microfabrication of hydrogels for the constructional analysis of cultured cellular networks with controlled network shapes and community sizes

    H. Moriguchi, K. Kojima, I. Suzuki, A. Hattori, T. Kaneko, K. Yasuda

    8th International Conference of Miniaturized Systems in Chemistry and Life Sciences (Micro Total Analysis Systems 2004)  (Malmö) 

    Presentation date： 2004.09

  • Control of the beating of cardiomyocytes by the constitutive arrangement of the connection to heterogeneous cells

    T. Kaneko, K. Kojima, K. Yasuda

    第57回日本細胞生物学会年会  (大阪) 

    Presentation date： 2004.05

  • Synchronize process of two-dimensional arranged cardiac myocytes in agar-microstructure chip

    K. Kojima, A. Hattori, T. Kaneko, K. Yasuda

    第57回日本細胞生物学会年会  (大阪) 

    Presentation date： 2004.05

  • Cell culture and purification of the selected cells on unilaminar close-packed microspheres

    Y. Anzai, H. Yamano, H. Moriguchi, A. Hattori, T. Kaneko, K. Yasuda

    第57回日本細胞生物学会年会  (大阪) 

    Presentation date： 2004.05

  • Single cell growth and division dynamics of Escherichia coli showing epigenetic correlations

    Yuichi Wakamoto, Jeremy Ramsden, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • Pattern modification of a neuronal network for on-chip single-cell-based electrophysiological measurement using photo-thermal etching of an agarose architecture with a multi-electrode array

    Ikurou Suzuki, Yoshihiro Sugio, Hiroyuki Moriguchi, Kazunori Takahashi, Tomoyuki Kaneko, Yasuhiko Jimbo, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • Single-cell based analysis of the dynamics of beating rhythm synchronization in two-dimensional-arranged cardiomyocytes

    Kensuke Kojima, Kazunori Takahashi, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • Long-term Simultaneous Measurement of Bacterial Growth and Motility under Controlled Nutrient Conditions on a Single-Cell Level

    Senkei Umehara, Yuichi Wakamoto, Akihiro Hattori, Ippei Inoue, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • On-chip single-cell analysis of Chlamydomonas cell cycle dynamics

    Kazunori Matsumura, Toshiki Yagi, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • New On-chip Agarose-gel Microfabrication Techniques using Agarose-gel Microstructures and Photo-thermal Etching Method for Topographical Control and Interaction Control of Cultured Cells during Cultivation

    Hiroyuki Moriguchi, Tomoyuki Kaneko, Kenji Yasuda

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • Stability of the Spontaneous Oscillatory Contraction (SPOC) in Single Myofibrils Studied byMechanical Response and Fluorescence Imaging

    Yuta Shimamoto, Hisashi Maejima, Madoka Suzuki, Daisuke Sasaki, Kenji Yasuda, Shin'ichi Ishiwata

    Biophysical Society 48th Annual meeting  (Baltimore) 

    Presentation date： 2004.02

  • Micro-patterning of polystyrene micro-beads covalently bound cell-secreted proteins

    H. Yamano, T. Kaneko, Y. Ito, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • Extracellular recordings from neuronal networks patterned by single cell level using multi-electrode-arrays combined with agarose-microstructures

    I. Suzuki, Y. Sugio, H. Moriguchi, K. Takahashi, T. Kaneko, Y. Jimbo, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • Response dynamics of PC12 cells induced with nerve growth factor attached to microspheres

    Y. Anzai, H. Yamano, H. Moriguchi, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • Single-cell based analysis of the dynamics of beating rhythm synchronization in two-dimesinonal-arranged cardiac myocytes

    K. Kojima, K. Takahashi, T. Kaneko, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • Synchronization of the beats in the cardiomyocytes controlled by heterogeneous cells

    T. Kaneko, K. Kojima, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • Patterning of neuronal network using agarose microstructure

    Y. Sugio, I. Suzuki, H. Moriguchi, K. Takahashi, T. Kaneko, Y. Jimbo, K. Yasuda

    The 21st Century COE Program "Research Center for Integrated Sciences" The First International Symposium "Interdisciplinary Studies on Life Systems,"  (Tokyo) 

    Presentation date： 2003.11

  • アガロース・マイクロ構造を用いて段階的に構成した神経細胞ネットワークのマイクロ電極アレイを用いた電気生理学特性計測技術の開発

    鈴木郁郎, 杉尾嘉宏, 森口裕之, 金子智行, 神保泰彦, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 二種類の赤外レーザを用いた細胞培養のためのアガロースゲル非接触三次元加工顕微鏡システムの開発

    服部明弘, 森口裕之, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 成長・運動同時計測による栄養条件変化への大腸菌一細胞順応ダイナミクス観察

    梅原千慶, 若本祐一, 服部明弘, 井之上一平, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 蛍光顕微解析による筋収縮系自励振動(SPOC)メカニズムの解明

    島本勇太, 鈴木団, 佐々木大輔, 安田賢二, 石渡信一

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • オンチップ１細胞長期培養系用のマイクロバルブ付きPDMSマイクロチャンバーの開発

    折田一樹, 高橋一憲, 松村和典, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • ゲルのマイクロストラクチャーを用いた培養細胞集団のトポグラフィー制御技術の開発

    森口裕之, 金子智行, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • クラミドモナス細胞周期ダイナミクスのオンチップ１細胞解析

    松村和典, 八木俊樹, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 2次元的パターン制御した心筋細胞拍動リズム形成ダイナミクスの1細胞計測

    小島健介, 高橋一憲, 金子智行, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 一定環境下における大腸菌表現型の1細胞世代間比較計測

    若本祐一, 梅原千慶, 井之上一平, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 微小ポリスチレンビーズ上に固定したNGFを用いた局所刺激に対するPC12細胞の分化応答の観察

    山野泰子, 金子智行, 伊藤嘉浩, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 顕微観察による細胞微細構造情報に基づく非侵襲オンチップセルソーターの開発

    高橋一, 服部明弘, 鈴木郁郎, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • 異種細胞による心筋細胞の拍動同期制御

    金子智行, 小島健介, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • オンチップ大腸菌一細胞培養系を用いた細胞内蛋白質ダイナミクスの計測

    井之上一平, 若本祐一, 塩見大輔, 川岸郁朗, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • マイクロビーズに固定した神経成長因子によるPC12細胞の選択的刺激とその伸長突起による多細胞ネットワーク形成

    安西悠, 山野泰子, 森口裕之, 金子智行, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • オンチップ細胞培養システムを用いた酵母プリオン様蛋白質の細胞内ダイナミクスの観測

    綾野賢, 野間繁子, 吉田賢右, 田口英樹, 安田賢二

    第4１回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • アガロース・マイクロストラクチャを用いた神経細胞ネットワークの段階的構成手法の開発

    杉尾嘉宏, 鈴木郁郎, 森口裕之, 金子智行, 安田賢二

    第41回日本生物物理学会年会  (新潟) 

    Presentation date： 2003.09

  • Observation of growth and division dynamics and stabilities of single Escherichia coli cells over a span of 10 generations

    Yuichi Wakamoto, Ippei Inoue, Kenji Yasuda

    Biophysical Society 47th Annual meeting  (San Antonio) 

    Presentation date： 2003.03

  • Memorization of the information on irreversible changes in Escherichia coli after environmental changes

    Senkei Umehara, Ippei Inoue, Kenji Yasuda

    Biophysical Society 47th Annual meeting  (San Antonio) 

    Presentation date： 2003.03

  • Fabrication of on-chip sorter devices with sub-micrometer scale channels and self-aligned microelectrodes

    T. Hara, T. Ichiki, Y. Horiike, K. Yasuda

    6th International Symposium on Micro Total Analysis System (Micro-TAS2002)  (Nara) 

    Presentation date： 2002.11

  • On-chip agarose microchamber (AMC) array cell-cultivation system for topographical control of neural network

    Hiroyuki Moriguchi, Kazunori Takahashi, Tomoyuki Kaneko, Kenji Yasuda

    6th International Symposium on Micro Total Analysis System (Micro-TAS2002)  (Nara) 

    Presentation date： 2002.11

  • On-chip neural cell-cultivation system for long-term observation with multi-electrode and microchamber arrays

    Kazunori Takahashi, Yoshihiro Sugio, Hiroyuki Moriguchi, Yasuhiko Jimbo, Kenji Yasuda

    6th International Symposium on Micro Total Analysis System (Micro-TAS2002)  (Nara) 

    Presentation date： 2002.11

  • アガロースマイクロチャンバーアレイ(AMCA)と集束レーザー光による局所加熱法を利用した培養神経ネットワークの形態制御

    森口裕之, 高橋一憲, 金子智行, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 一次元配列した培養心筋細胞の拍動リズム同期ダイナミクスの解析

    小島健介, 高橋一憲, 服部明弘, 金子智行, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 栄養条件変化に対する大腸菌一細胞レベルの適応機構の検討

    梅原千慶, 井之上一平, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 一細胞長期培養系を用いた光量変化に対するクラミドモナス細胞分裂サイクルの応答解析

    松村和典, 若本祐一, 八木俊樹, 神谷律, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • オンチップ大腸菌長期1細胞観察法を用いた成長・分裂ダイナミクスの世代間比較計測

    若本祐一, 井之上一平, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 心筋細胞との共培養によるPC12細胞の分化誘導

    金子智行, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • マイクロビーズ上に固定した細胞増殖因子を用いた局所刺激に対するPC12細胞の分化応答の観察

    山野泰子, 金子智行, 伊藤嘉浩, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 神経細胞ネットワークの形状制御のための培養細胞配置技術の開発

    杉尾嘉宏, 高橋一憲, 服部明弘, 金子智行, 神保泰彦, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 光ピンセットが細胞に与えるダメージの定量的検討

    綾野賢, 山下志乃舞, 若本祐一, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 位相差／蛍光デュアル顕微画像処理を組み込んだオンチップセルソータの開発

    高橋一憲, 服部明弘, 一木隆範, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • マイクロ加工と画像処理を用いた大腸菌一細胞の成長過程における運動パターン変化解析技術

    服部明弘, 若本祐一, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • オンチップ一細胞長期培養観察系による細胞動態のタイムラプス計測

    金子智行, 服部明弘, 高橋一憲, 井之上一平, 山野泰子, 森口裕之, 杉尾嘉宏, 若本祐一, 小島健介, 梅原千慶, 松村和典, 綾野賢, 安田賢二

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 力学的刺激による筋収縮系自励振動(SPOC)メカニズムの研究

    島本勇太, 鈴木団, 安田賢二, 石渡信一

    第40回日本生物物理学会年会  (名古屋) 

    Presentation date： 2002.11

  • 力学刺激による骨格筋収縮系自励振動の制御

    島本勇太, 鈴木団, 安田賢二, 石渡信一

    第57回日本物理学会年次大会  (東京、名古屋) 

    Presentation date： 2002.09

  • A minimal length of Escherichia coli

    Senkei Umehara, I. Inoue, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Variety of long-term isolated single cells of Escherichia coli and differences in cells derived from one ancestor

    Yuichi Wakamoto, I. Inoue, H. Moriguchi, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Non-genetic Variability of Cell Growth and Division of Isolated Individual Bacteria in On-chip Culture System

    Ippei Inoue, Y. Wakamoto, H. Moriguchi, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Development of on-chip time-lapse analysis system for continuous observation of single cells

    Akihiro Hattori, I. Inoue, Y. Wakamoto, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Development of micro-multi-electrode array chip system for multi-site stimulation/analysis of nerve cells network

    Yoshihiro Sugio, K. Takahashi, H. Moriguchi, T. Isami, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • On-chip agar-microchamber system for single cells cultivation and observation

    Hiroyuki Moriguchi, K. Takahashi, Y. Wakamoto, Y. Sugio, I. Inoue, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Selective recovery of screened DNA/RNA on DNA chip for full-length analysis using laser assisted photo-thermal denaturation method

    Kazunori Takahashi, H. Kazuhiro, K. Okano, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Studies on photodamage of optical trap to bacteria

    Shinobu Yamashita, Y. Wakamoto, K. Yasuda

    Biophysical Society 46th Annual meeting  (San Francisco) 

    Presentation date： 2002.02

  • Observation of individual cell using on-chip culture system

    I. Inoue, Y. Wakamoto, H. Moriguchi, K. Okano, K. Yasuda

    5th International Symposium on Micro Total Analysis System (Micro-TAS2001)  (Monterey) 

    Presentation date： 2001.10

  • On-chip cell corter for single cell expression analysis

    T. Ichiki, T. Ujiie, T. Hara, Y. Horiike, K. Yasuda

    5th International Symposium on Micro Total Analysis System (Micro-TAS2001)  (Monterey) 

    Presentation date： 2001.10

  • Differential analysis of single-cell cultivation using on-chip microculture system and optical trapping

    Y. Wakamoto, I. Inoue, H. Moriguchi, K. Yasuda

    5th International Symposium on Micro Total Analysis System (Micro-TAS2001)  (Monterey) 

    Presentation date： 2001.10

  • Agar Micro-chamber ―マイクロファブリケーションの細胞培養観察系への新しい応用―

    森口裕之, 若本祐一, 杉尾嘉宏, 高橋一憲, 井之上一平, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • マイクロ多電極アレイを用いた神経回路刺激計測装置系の開発

    杉尾嘉宏, 勇隆仁, 森口裕之, 高橋一憲, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 一細胞顕微培養観察のためのオンチップタイムラプス計測システムの開発

    服部明弘, 井之上一平, 若本祐一, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • DNAチップを用いた一細胞遺伝子発現解析のためのレーザー局所加熱法によるmRNAの空間選択的回収の検討

    高橋一憲, 服部明弘, 岡野和宣, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 大腸菌直系子孫細胞の成長・分裂における差分値計測

    若本祐一, 井之上一平, 森口裕之, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 同一環境下での姉妹大腸菌の成長・分裂比較計測

    井之上一平, 若本祐一, 森口裕之, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 骨格筋収縮系SPOCは力学的な外部刺激に同調する

    島本勇太, 鈴木団, 安田賢二, 石渡信一

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 化学反応で複製するジャイアントベシクルのリアルタイム観察

    豊田太郎, 高倉克人, 山田幸司, 石丸真子, 安田賢二, 菅原正

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • 大腸菌の成長最小長さの検討

    梅原千慶, 井之上一平, 安田賢二

    第39回日本生物物理学会年会  (大阪) 

    Presentation date： 2001.10

  • Difference between close relatives of Escherichia coli

    Yuichi Wakamoto, Ippei Inoue, Hiroyuki Moriguchi, Kenji Yasuda

    4th International Conference on Biological Physics  (Kyoto) 

    Presentation date： 2001.08

  • Observation of individual E. coli immobilized by semipermeable membrane wrapping method

    森口裕之, 井之上一平, 若本祐一, 岡野和宣, 大沼清, 四方哲也, 金子邦彦, 安田賢二

    第56回日本物理学会年次大会  (東京) 

    Presentation date： 2001.03

  • 一細胞顕微培養観察装置系を用いた大腸菌娘細胞の成長比較

    井之上一平, 若本祐一, 森口裕之, 柏木明子, 四方哲也, 金子邦彦, 安田賢二

    第56回日本物理学会年次大会  (東京) 

    Presentation date： 2001.03

  • マイクロ加工技術と光ピンセットを用いたセルソーティングシステムの開発

    若本祐一, 井之上一平, 森口裕之, 安田賢二

    第56回日本物理学会年次大会  (東京) 

    Presentation date： 2001.03

  • Culture system for observation of individual bacteria

    Ippei Inoue, Yuichi Wakamoto, Kiyoshi Onuma, Akiko Kashiwagi, Kunihiko Kaneko, Tetsuya Yomo, Kenji Yasuda

    Biophysical Society 45th Annual Meeting  (Boston) 

    Presentation date： 2001.02

  • 顕微培養観察装置系を用いた一定栄養条件下での大腸菌分裂の個体レベル観察

    井之上一平, 若本祐一, 大沼清, 柏木明子, 四方哲也, 金子邦彦, 安田賢二

    第38回日本生物物理学会年会  (仙台) 

    Presentation date： 2000.09

  • ジャイアントリポソームの自己複製反応システムの解析

    豊田太郎, 山田幸司, 高倉克人, 安田賢二, 四方哲也, 菅原正

    第38回日本生物物理学会年会  (仙台) 

    Presentation date： 2000.09

  • サイズ・パターン制御されたニワトリ胚培養心筋細胞ネットワークの研究

    新原岳雄, 大沼清, 石渡信一, 安田賢二

    第38回日本生物物理学会年会  (仙台) 

    Presentation date： 2000.09

  • 光ピンセットがEscherichia coliに与えるダメージの検討

    若本祐一, 井之上一平, 大沼清, 柏木明子, 四方哲也, 金子邦彦, 安田賢二

    第38回日本生物物理学会年会  (仙台) 

    Presentation date： 2000.09

  • Non-destructive mixing concentration fractionation and separation of μm-sized particles in liquid by ultrasound

    Kenji Yasuda

    4th International Symposium on Micro Total Analysis System (Micro-TAS2000)  (Enschede) 

    Presentation date： 2000.05

  • DNA preparation by using a DNA chip

    Kazunori Okano, Gang Chen, Kenji Yasuda, Shin’ichi Ishiwata

    4th International Symposium on Micro Total Analysis System (Micro-TAS2000)  (Enschede) 

    Presentation date： 2000.05

  • 集束レーザー局所加熱によるDNAチップからのDNA選択回収

    安田賢二, 岡野和宣, 五嶋淳, 野崎貴之, 石渡信一

    第37回日本生物物理学会年会  (埼玉) 

    Presentation date： 1999.10

▼display all

Specific Research

  • マクロファージの多点連続刺激の細胞内での情報処理機構の解明

    2021  

    　View Summary

    Macrophage is one of the immune cells in organisms which differentiate from monocytes and reside in various organs and is indispensable to our innate and adaptive immunity. However, the mechanism of phagocytosis is only partially understood, with key insights provided more than three decades ago. For example, the zipper model explained the driving mechanism of the engulfment procedure and its specific identification of antigens during phagocytosis in macrophages. To confirm the ability and limitation of this Zipper model in the critical conditions, we tracked the progression of the macrophage membrane engulfing the IgG-coated polystyrene beads and IgG-coated microneedles after reaching the maximum engulfment capacity. The results showed that the irregular membrane backtracking as the reverse phenomenon of engulfment was observed after macrophages reached the maximum engulfment capacity regardless of the difference of the shapes of antigens. We also evaluated the correlation of engulfment in simultaneous or series stimulations of two IgG-coated microneedles and found that they both reversed independently. However, the critical elongation size of membrane extension in each microneedle was smaller than the single microneedle engulfment. These results indicate that the mechanism of engulfment should imply (1) the function of reverse engulfment after they reach the maximum capacity before the completion of engulfment was included for their survival, and its recovery, (2) asynchronous backtracking in two-microneedle stimulation indicates the phagocytosis is the local phenomenon of macrophage membrane, and (3) the decrease of the maximum capacity in each of two-microneedle stimulation suggests the maximum capacity is not determined only by mere local cell membrane capacity but also by whole-cell volume increase information.

  • マクロファージの多点連続刺激の細胞内での情報処理機構の解明

    2020  

    　View Summary

    Zipper model explained the driving mechanism of the engulfment procedure and its specific identification of antigens during phagocytosis in macrophages. To confirm the ability and limitation of this Zipper model in the critical conditions, we observed the phagocytosis after reached to the maximum engulfment capacity and the phagocytosis of the clusters of the IgG-coated and non-coated polystyrene sphere mixtures. We tracked the progression of membrane engulfing the IgG-coated polystyrene beads and IgG-coated microneedles. For the cluster engulfment, we recorded the time course of the cluster of different size IgG-coated/non-coated polystyrene spheres to confirm their strict selection of target antigens from the mixture cluster. The results showed that the irregular membrane backtracking as the reverse phenomenon of engulfment was observed after macrophages reached the maximum engulfment capacity. When the selective engulfment of IgG-coated polystyrene spheres from the mixtures cluster was not always successful, and sometimes, non-coated polystyrene spheres were caught into the cell body accompany with engulfment of the IgG-coated polystyrene sphere part of the cluster. In contrast, no membrane backtracking was observed during the engulfment of clusters. These results indicate that the mechanism of engulfment should imply the function of regurgitation for their survival and its recovery.

  • マクロファージの多点連続刺激の細胞内での情報処理機構の解明

    2019  

    　View Summary

    本課題研究では、マクロファージの自他認識と貪食応答の機構を、従来の細胞膜の局所での分子レベルでの刺激応答という観点から細胞の情報処理の機構の解明という新しい観点での研究を推進した。光ピンセット、メカニカルマイクロマニピュレーターを用いて、マクロファージの特定の１点あるいは特定の複数点に連続してオプソニン化したPM2.5粒子の貪食を繰り返し行ったところ、一定の細胞膜の貪食応答が進んだところで他の領域の応答性はブロックされて他の抗原には応答を開始しないことが確認された。この結果は、貪食現象が単なる細胞膜の局所応答機構のみでは説明できるものではないことが示唆された。

  • オンチップ心筋細胞ネットワーク計測系を用いた拍動同期現象の集団効果の解明

    2018  

    　View Summary

    本課題研究では、まず心筋細胞が集団化した時の「集団としての拍動状態」を、この集団を構成する各細胞の振る舞い、協同性や互いの興奮伝導などの状態と比較して「集団の表現型」が創り出される原理の解明を目指した。まず孤立培養したマウス初代心筋細胞、ヒトiPS細胞由来心筋細胞、ヒトES細胞由来心筋細胞の各細胞の拍動周期と拍動の安定性の分布と、これらの細胞が集団（クラスター）となった時の拍動の特性を比較し、細胞集団（クラスター）の拍動周期は、最も早い孤立心筋細胞の拍動周期より遅くなり、また、拍動周期の安定性は改善した。これは従来、基盤と考えられていたOverdrive Suppression仮説に反するものであり新規の発見であった。

  • マクロファージの多点刺激の情報処理機構の解明

    2018  

    　View Summary

    本課題研究では、マクロファージの自他認識と貪食応答の機構を、従来の細胞膜の局所での応答、という観点ではなく「細胞全体としてどのように応答を選択するのか。また、受けた刺激は細胞に履歴を残すのか。」という、細胞の複数情報処理についての素朴な疑問として解明を目指した。ここでは、実際に、光ピンセット、あるいは、メカニカルマイクロマニピュレーターを用いて、マクロファージの特定の１点に連続して貪食を繰り返させることで、貪食がどのような変化をするのかを測定した。その結果は、貪食現象が単なる細胞膜の局所応答機構のみでは説明できるものではなく、従来の報告にはない細胞全体としての情報共有機構の存在を示唆するものであった。

  • マクロファージの多点刺激の情報処理機構の解明

    2017  

    　View Summary

    本課題研究では、「細胞が複数の競合する同種（貪食）刺激を受けたら、細胞全体としてどのように応答を選択するのか。また、受けた刺激は細胞に履歴を残すのか。」という、細胞の複数情報処理についての素朴な疑問を、マクロファージの貪食という自他認識・判断能力が顕著で、かつ、応答が貪食という行為で容易に判別できる系をモデルとして選び解明を目指した。個々の細胞に直接触って、その細胞膜表面への力学刺激量を一定にしたところでの細胞応答の定量計測・制御・操作可能なマイクロ力学マニピュレーション技術を利用し、免疫1細胞の多点刺激に対する細胞レベルの応答を時空間的観点から機能解明することを目指した。その結果 (1)新しい多点定量力学刺激・細胞応答計測技術の開発、および(2)１細胞への競合する複数刺激情報入力時の細胞内情報処理・応答のダイナミクス解明を推進することができた。

  • マクロファージの多点刺激の情報処理機構の解明

    2017  

    　View Summary

    本課題研究では、「細胞が複数の競合する同種（貪食）刺激を受けたら、細胞全体としてどのように応答を選択するのか。また、受けた刺激は細胞に履歴を残すのか。」という、細胞の複数情報処理についての素朴な疑問を、マクロファージの貪食という自他認識・判断能力が顕著で、かつ、応答が貪食という行為で容易に判別できる系をモデルとして選び解明を目指した。個々の細胞に直接触って、その細胞膜表面への力学刺激量を一定にしたところでの細胞応答の定量計測・制御・操作可能なマイクロ力学マニピュレーション技術を利用し、免疫1細胞の多点刺激に対する細胞レベルの応答を時空間的観点から機能解明することを目指した。その結果 (1)新しい多点定量力学刺激・細胞応答計測技術の開発、および(2)１細胞への競合する複数刺激情報入力時の細胞内情報処理・応答のダイナミクス解明を推進することができた。

  • 心筋細胞集団の興奮伝導の協働現象の理解とその創薬応用の検討

    2016  

    　View Summary

    周期的興奮の協同性を巧みに利用してポンプ機能を実現する心筋細胞を用いて、構成的に構築した心筋細胞ネットワークの動的協同（拍動）現象の機構の解明を進めた。実際の研究を進めるにあたっては、特に本課題開始前の前年度より課題としていた「細胞の精製」を行うためのイメージングセルソーター技術の改良と血中がん細胞検出への応用、「心筋細胞の配置技術の改良とこの神経細胞ネットワークへの展開」、心筋細胞集団の同期化の機構の数理モデルとの融合、マクロファージ細胞を用いた細胞表面の局所刺激情報の履歴の検証、などの一連の過去の研究のまとめと萌芽的研究の開始を行い、講演等８件、論文１件（投稿中２件）の成果を得た。

▼display all

 

Syllabus

▼display all