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

doi:10.3390/mi11121105

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

Micromachines ◽

10.3390/mi11121105 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1105

Author(s):

Kazufumi Sakamoto ◽

Shota Aoki ◽

Yuhei Tanaka ◽

Kenji Shimoda ◽

Yoshitsune Hondo ◽

...

Keyword(s):

Time Distribution ◽

Embryonic Stem ◽

Propagation Time ◽

Conduction Time ◽

Field Potentials ◽

Es Cell ◽

Geometrical Arrangement ◽

Sampling Intervals ◽

Microfabrication Technology ◽

Cell Networks

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.

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Measurement and simulation of the neutron propagation time distribution inside a neutron monitor

Astroparticle Physics ◽

10.1016/j.astropartphys.2021.102617 ◽

2021 ◽

pp. 102617

Author(s):

K. Chaiwongkhot ◽

D. Ruffolo ◽

W. Yamwong ◽

J. Prabket ◽

P.-S. Mangeard ◽

...

Keyword(s):

Neutron Monitor ◽

Time Distribution ◽

Propagation Time ◽

Neutron Propagation

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Production of Mice Entirely Derived from Embryonic Stem (ES) Cell with Many Passages by Coculture of ES Cells with Cytochalasin B Induced Tetraploid Embryos.

Experimental Animals ◽

10.1538/expanim.44.205 ◽

1995 ◽

Vol 44 (3) ◽

pp. 205-210 ◽

Cited By ~ 32

Author(s):

Otoya UEDA ◽

Kouichi JISHAGE ◽

Nobuo KAMADA ◽

Satomi UCHIDA ◽

Hiroshi SUZUKI

Keyword(s):

Cytochalasin B ◽

Es Cells ◽

Embryonic Stem ◽

Es Cell

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Germ line transmission of an inactive N-myc allele generated by homologous recombination in mouse embryonic stem cells

Molecular and Cellular Biology ◽

10.1128/mcb.10.12.6755-6758.1990 ◽

1990 ◽

Vol 10 (12) ◽

pp. 6755-6758

Author(s):

B R Stanton ◽

S W Reid ◽

L F Parada

Keyword(s):

Stem Cells ◽

Embryonic Stem Cells ◽

Homologous Recombination ◽

Embryonic Development ◽

Cell Lines ◽

Germ Line ◽

Es Cells ◽

Embryonic Stem ◽

Es Cell ◽

Germ Line Transmission

We have disrupted one allele of the N-myc locus in mouse embryonic stem (ES) cells by using homologous recombination techniques and have obtained germ line transmission of null N-myc ES cell lines with transmission of the null N-myc allele to the offspring. The creation of mice with a deficient N-myc allele will allow the generation of offspring bearing null N-myc alleles in both chromosomes and permit study of the role that this proto-oncogene plays in embryonic development.

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Brachyury - a gene affecting mouse gastrulation and early organogenesis

Development ◽

10.1242/dev.116.supplement.157 ◽

1992 ◽

Vol 116 (Supplement) ◽

pp. 157-165 ◽

Cited By ~ 20

Author(s):

R. S. P. Beddington ◽

P. Rashbass ◽

V. Wilson

Keyword(s):

Es Cells ◽

Embryonic Stem ◽

Primitive Streak ◽

Coat Colour ◽

Es Cell ◽

Wild Type ◽

Mesoderm Cell ◽

Rostrocaudal Axis

Mouse embryos that are homozygous for the Brachyury (T) deletion die at mid-gestation. They have prominent defects in the notochord, the allantois and the primitive streak. Expression of the T gene commences at the onset of gastrulation and is restricted to the primitive streak, mesoderm emerging from the streak, the head process and the notochord. Genetic evidence has suggested that there may be an increasing demand for T gene function along the rostrocaudal axis. Experiments reported here indicate that this may not be the case. Instead, the gradient in severity of the T defect may be caused by defective mesoderm cell movements, which result in a progressive accumulation of mesoderm cells near the primitive streak. Embryonic stem (ES) cells which are homozygous for the T deletion have been isolated and their differentiation in vitro and in vivo compared with that of heterozygous and wild-type ES cell lines. In +/+ ↔ T/T ES cell chimeras the Brachyury phenotype is not rescued by the presence of wild-type cells and high level chimeras show most of the features characteristic of intact T/T mutants. A few offspring from blastocysts injected with T/T ES cells have been born, several of which had greatly reduced or abnormal tails. However, little or no ES cell contribution was detectable in these animals, either as coat colour pigmentation or by isozyme analysis. Inspection of potential +/+ ↔ T/T ES cell chimeras on the 11th or 12th day of gestation, stages later than that at which intact T/T mutants die, revealed the presence of chimeras with caudal defects. These chimeras displayed a gradient of ES cell colonisation along the rostrocaudal axis with increased colonisation of caudal regions. In addition, the extent of chimerism in ectodermal tissues (which do not invaginate during gastrulation) tended to be higher than that in mesodermal tissues (which are derived from cells invaginating through the primitive streak). These results suggest that nascent mesoderm cells lacking the T gene are compromised in their ability to move away from the primitive streak. This indicates that one function of the T genemay be to regulate cell adhesion or cell motility properties in mesoderm cells. Wild-type cells in +/+ ↔ T/T chimeras appear to move normally to populate trunk and head mesoderm, suggesting that the reduced motility in T/T cells is a cell autonomous defect

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Human embryonic stem cells: challenges and opportunities

Reproduction Fertility and Development ◽

10.1071/rd06113 ◽

2006 ◽

Vol 18 (8) ◽

pp. 839 ◽

Cited By ~ 3

Author(s):

Steven L. Stice ◽

Nolan L. Boyd ◽

Sujoy K. Dhara ◽

Brian A. Gerwe ◽

David W. Machacek ◽

...

Keyword(s):

Stem Cells ◽

Neural Stem Cells ◽

Cell Line ◽

Cell Fate ◽

Neural Development ◽

Es Cells ◽

Embryonic Stem ◽

Normal Karyotype ◽

Es Cell ◽

Cell Therapies

Human and non-human primate embryonic stem (ES) cells are invaluable resources for developmental studies, pharmaceutical research and a better understanding of human disease and replacement therapies. In 1998, subsequent to the establishment of the first monkey ES cell line in 1995, the first human ES cell line was developed. Later, three of the National Institute of Health (NIH) lines (BG01, BG02 and BG03) were derived from embryos that would have been discarded because of their poor quality. A major challenge to research in this area is maintaining the unique characteristics and a normal karyotype in the NIH-registered human ES cell lines. A normal karyotype can be maintained under certain culture conditions. In addition, a major goal in stem cell research is to direct ES cells towards a limited cell fate, with research progressing towards the derivation of a variety of cell types. We and others have built on findings in vertebrate (frog, chicken and mouse) neural development and from mouse ES cell research to derive neural stem cells from human ES cells. We have directed these derived human neural stem cells to differentiate into motoneurons using a combination of developmental cues (growth factors) that are spatially and temporally defined. These and other human ES cell derivatives will be used to screen new compounds and develop innovative cell therapies for degenerative diseases.

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A lack of foresight? Jurisdictional uncertainties in the regulatory interface between the HFEA, the UK Stem Cell Bank and beyond

Legal Studies ◽

10.1111/j.1748-121x.2007.00055.x ◽

2007 ◽

Vol 27 (3) ◽

pp. 511-535 ◽

Cited By ~ 1

Author(s):

Ryan Morgan

Keyword(s):

Embryonic Stem ◽

Embryo Research ◽

Es Cell ◽

Statutory Interpretation ◽

Cell Bank ◽

Human Fertilisation ◽

Department Of Health ◽

Regulatory Architecture ◽

Policy Objectives ◽

The Uk

Much of the legal attention surrounding human embryonic stem (ES) cell research within the UK has, to date, focused on cloning techniques. Whilst this is both understandable and appropriate given litigation on this topic, there has been less focus on other areas. This paper identifies and analyses areas of incoherence and deficiency within the regulatory architecture governing human ES cell derivation and research within the UK. This is not merely a theoretical exercise, as there are indications that many of the policy objectives currently being pursued in this area have, at best, a shaky jurisdictional basis. It is all too easy to recall that lobby groups have challenged the Human Fertilisation and Embryology Act 1990, the legislative foundation for embryo research and most infertility treatment, on the basis of jurisdictional uncertainty and statutory interpretation. Whilst many pro-life campaigners are opposed to ES cell research on ethical grounds, the arguments utilised thus far in relation to litigation have been entirely legal, involving issues of statutory interpretation and whether the regulator, the Human Fertilisation and Embryology Authority (HFEA), or the Department of Health have acted ultra vires the 1990 Act. This paper will reveal that there are a number of further areas which might be open to attack on this basis.

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Designer blood: creating hematopoietic lineages from embryonic stem cells

Blood ◽

10.1182/blood-2005-09-3621 ◽

2006 ◽

Vol 107 (4) ◽

pp. 1265-1275 ◽

Cited By ~ 51

Author(s):

Abby L. Olsen ◽

David L. Stachura ◽

Mitchell J. Weiss

Keyword(s):

Stem Cells ◽

Es Cells ◽

Embryonic Stem ◽

Basic Research ◽

Cell Types ◽

Patient Specific ◽

Es Cell ◽

Blood Disorders ◽

Hematopoietic Stem

Embryonic stem (ES) cells exhibit the remarkable capacity to become virtually any differentiated tissue upon appropriate manipulation in culture, a property that has been beneficial for studies of hematopoiesis. Until recently, the majority of this work used murine ES cells for basic research to elucidate fundamental properties of blood-cell development and establish methods to derive specific mature lineages. Now, the advent of human ES cells sets the stage for more applied pursuits to generate transplantable cells for treating blood disorders. Current efforts are directed toward adapting in vitro hematopoietic differentiation methods developed for murine ES cells to human lines, identifying the key interspecies differences in biologic properties of ES cells, and generating ES cell-derived hematopoietic stem cells that are competent to repopulate adult hosts. The ultimate medical goal is to create patient-specific and generic ES cell lines that can be expanded in vitro, genetically altered, and differentiated into cell types that can be used to treat hematopoietic diseases.

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Transplantation of embryonic stem cells improves cardiac function in postinfarcted rats

Journal of Applied Physiology ◽

10.1152/jappl.2002.92.1.288 ◽

2002 ◽

Vol 92 (1) ◽

pp. 288-296 ◽

Cited By ~ 209

Author(s):

Jiang-Yong Min ◽

Yinke Yang ◽

Kimber L. Converso ◽

Lixin Liu ◽

Qin Huang ◽

...

Keyword(s):

Cardiac Function ◽

Cell Transplantation ◽

Troponin I ◽

Es Cells ◽

Single Cells ◽

Embryonic Stem ◽

Control Group ◽

Positive Staining ◽

Es Cell ◽

Intramyocardial Injection

Massive loss of cardiac myocytes after myocardial infarction (MI) is a common cause of heart failure. The present study was designed to investigate the improvement of cardiac function in MI rats after embryonic stem (ES) cell transplantation. MI in rats was induced by ligation of the left anterior descending coronary artery. Cultured ES cells used for cell transplantation were transfected with the marker green fluorescent protein (GFP). Animals in the treated group received intramyocardial injection of ES cells in injured myocardium. Compared with the MI control group injected with an equivalent volume of the cell-free medium, cardiac function in ES cell-implanted MI animals was significantly improved 6 wk after cell transplantation. The characteristic phenotype of engrafted ES cells was identified in implanted myocardium by strong positive staining to sarcomeric α-actin, cardiac α-myosin heavy chain, and troponin I. GFP-positive cells in myocardium sectioned from MI hearts confirmed the survival and differentiation of engrafted cells. In addition, single cells isolated from cell-transplanted MI hearts showed rod-shaped GFP-positive myocytes with typical striations. The present data demonstrate that ES cell transplantation is a feasible and novel approach to improve ventricular function in infarcted failing hearts.

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Assessment of the ultrastructural and proliferative properties of human embryonic stem cell-derived cardiomyocytes

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00020.2003 ◽

2003 ◽

Vol 285 (6) ◽

pp. H2355-H2363 ◽

Cited By ~ 210

Author(s):

Mirit Snir ◽

Izhak Kehat ◽

Amira Gepstein ◽

Raymond Coleman ◽

Joseph Itskovitz-Eldor ◽

...

Keyword(s):

Cell Cycle ◽

Stem Cell ◽

Embryonic Stem Cell ◽

Late Stage ◽

Human Embryonic Stem Cell ◽

Embryonic Stem ◽

Es Cell ◽

Cardiomyocyte Proliferation ◽

Ki 67

Assessment of early ultrastructural development and cell-cycle regulation in human cardiac tissue is significantly hampered by the lack of a suitable in vitro model. Here we describe the possible utilization of human embryonic stem cell (ES) lines for investigation of these processes. With the use of the embryoid body (EB) differentiation system, human ES cell-derived cardiomyocytes at different developmental stages were isolated and their histomorphometric, ultrastructural, and proliferative properties were characterized. Histomorphometric analysis revealed an increase in cell length, area, and length-to-width ratio in late-stage EBs (>35 days) compared with early (10–21 days) and intermediate (21–35 days) stages. This was coupled with a progressive ultrastructural development from an irregular myofibrillar distribution to an organized sarcomeric pattern. Cardiomyocyte proliferation, assessed by double labeling with cardiac-specific antibodies and either [3H]thymidine incorporation or Ki-67 immunolabeling, demonstrated a gradual withdrawal from cell cycle. Hence, the percentage of positively stained nuclei in early-stage cardiomyocytes ([3H]thymidine: 60 ± 10%, Ki-67: 54 ± 23%) decreased to 36 ± 7% and 9 ± 16% in intermediate-stage EBs and to <1% in late-stage cardiomyocytes. In conclusion, a reproducible temporal pattern of early cardiomyocyte proliferation, cell-cycle withdrawal, and ultrastructural maturation was noted in this model. Establishment of this unique in vitro surrogate system may allow to examine the molecular mechanisms underlying these processes and to assess interventions aiming to modify these properties. Moreover, the detailed characterization of the ES cell-derived cardiomyocyte may be crucial for the development of future cell replacement strategies aiming to regenerate functional myocardium.

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