Download or read book Stochastic Models of Intracellular Calcium Release and Alternans written by Robert James Rovetti and published by . This book was released on 2008 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stochastic Models of Intracellular Calcium Signals written by Sten Rüdiger and published by . This book was released on 2014 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biophysical Modelling of the Genesis of Alternans InCardiac Intracellular Ca2 Handling written by Tao Tao and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardiac mechanical alternans are believed to be associated with intracellular Ca2 + alternans. However, the mechanisms underlying the genesis of intracellular Ca2 + alternans are unclear. Experimental studies have shown that alternans of systolic Ca2 + under voltage clamp can be produced either by partially inhibiting the Ca2+ release mechanism or by applying small depolarising pulses. In each case the alternans relied on the appearance of propagating waves of Ca2 + release. The aim of the work in this thesis is to develop a theoretical model to understand the mechanisms underlying how the beat-to-beat alternation in the amplitude of the systolic Ca2+ transient is produced. A mathematical model of intracellular Ca2 + handling for a ventricular cardiac cell was developed as a spatially extended object, which is discretized by a group of coupled elements. Each element contains L-type and T-type Ca2 + channels, a subspace into which Ca2 + release takes place, a cytoplasmic space and sarcoplasmic reticulum (SR) release channels (RyR) and uptake sites (SERCA). Inter-element coupling is via Ca2 + diffusion between neighbouring subspaces and cytoplasm spaces. Small depolarising pulses were simulated by a sequence of step changes of cell membrane potential (20 mV) with random block on the L-type channels. Partial inhibition of the release mechanism is mimicked by applying a random reduction of the open probability of the RyR in response to a full stimulation by L type Ca2 + channels. In both cases the simulations are consistent with experimental observations and show that Ca2 + alternans can be generated and sustained through alternation of SR Ca2+ content produced by the propagating wave of Ca2 + release. However, the presented model has certain limitations. In the model, the property of L-type Ca2 + channel is described as an average effect of global current in a cardiac cell, rather than the total current of a large population of unitary L-type Ca2 + current, which is directly associated with the testing potential and which is a very important part of Ca2 + induced Ca2 + release (CICR). To conquer the limitation, an improved version of the Ca2 + handling model was developed by incorporating stochastic unitary L-type Ca2 + channels into the previous model. The improved model has a more biophysically detailed Ca2 + handling model, which can not only simulate proper unitary L-type Ca2 + influx but also produce a good quality of global L-type Ca2 + current. Like the old model the new stochastic model produced the global and regional alternans of Ca2 + transients observed in previous experimental studies as well, and agreed the key role of SR Ca2 + content to genesis of cardiac Ca2 + alternans. The study in this thesis provided novel insights into understanding the mechanisms underlying the genesis of intracellular Ca2 + alternans. In addition, the simulation study of effects of volatile anesthesics on rat ventricle has also been included in this thesis, and is presented in Appendix 1.
Download or read book Mathematical Modelling of Intracellular Ca2 Alternans in Atrial and Ventricular Myocytes written by Qince Li and published by . This book was released on 2012 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: During excitation-contraction coupling, Ca2+ transient induced by the depolarization of membrane potential is the trigger of mechanical contraction in cardiac myocytes, which is responsible for the pumping function of the heart. However, mechanisms underlying intracellular Ca2+ regulation and the coupling between Ca2+ transient and membrane potential are not completely understood. Abnormalities in intracellular Ca2+ regulation have been observed during heart failure and cardiac arrhythmias, such as intracellular Ca2+ alternans and T-tubule disorganization. In this project, intracellular Ca2+ dynamics in different types of cardiac myocytes were investigated by using computer modelling. For atrial myocytes, a biophysically detailed computer model was developed to describe the observations of Ca2+ alternans and Ca2+ wave propagation in cardiac myocytes lacking T-tubules. The model was validated by its ability to reproduce experimental observed Ca2+ wave propagation under normal condition and the influences on spatial Ca2+ distribution by modifying various aspects of Ca2+ cycling, such as Ca2+ influx, SR Ca2+ uptake and SR Ca2+ release in cardiac myocytes lacking T-tubules. Mechanisms underlying the genesis of Ca2+ alternans in this type of cell were investigated by the model. Furthermore, a spontaneous second Ca2+ release was observed in response to a single voltage stimulus pulse with enhanced Ca2+ influx as well as SR Ca2+ overload. For the ventricular myocytes, an existing canine model was used to study the genesis of APD and intracellular Ca2+ alternans under various conditions. The genesis of Ca2+ alternans was investigated by analyzing the relationship between systolic Ca2+ concentration and SR Ca2+ content. On the other side, the roles of SR Ca2+ regulation and action potential restitution in the genesis of intracellular Ca2+ and APD alternans were also examined under various conditions. In addition, it was shown that spatially discordant Ca2+ alternans was generated when the Ca2+-dependent inactivation of ICa, L was strong. It tended to be concordant for weak Ca2+-dependent inactivation of ICa, L. For the sinoatrial node cells, a mathematical model was developed to simulate stochastic opening of unitary L-type Ca2+ channel and single RyR channel, thereby reproducing experimental observed local Ca2+ release during diastolic depolarization phase of the action potential. Simulation results of ionic channel block and modifications of SR Ca2+ regulation suggested a limited role of intracellular Ca2+ in the automaticity of central SA node cells.
Download or read book Issues in Logic Probability Combinatorics and Chaos Theory 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Logic, Probability, Combinatorics, and Chaos Theory: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Logic, Probability, Combinatorics, and Chaos Theory. The editors have built Issues in Logic, Probability, Combinatorics, and Chaos Theory: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Logic, Probability, Combinatorics, and Chaos Theory in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Logic, Probability, Combinatorics, and Chaos Theory: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Nanodomain Regulation of Muscle Physiology and Alterations in Disease written by Niall Macquaide and published by Frontiers Media SA. This book was released on 2023-01-03 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Dynamics in Biological Systems written by Jorge Carballido-Landeira and published by Springer. This book was released on 2016-07-20 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent research results relating to applications of nonlinear dynamics, focusing specifically on four topics of wide interest: heart dynamics, DNA/RNA, cell mobility, and proteins. The book derives from the First BCAM Workshop on Nonlinear Dynamics in Biological Systems, held in June 2014 at the Basque Center of Applied Mathematics (BCAM). At this international meeting, researchers from different but complementary backgrounds, including molecular dynamics, physical chemistry, bio-informatics and biophysics, presented their most recent results and discussed the future direction of their studies using theoretical, mathematical modeling and experimental approaches. Such was the level of interest stimulated that the decision was taken to produce this publication, with the organizers of the event acting as editors. All of the contributing authors are researchers working on diverse biological problems that can be approached using nonlinear dynamics. The book will appeal especially to applied mathematicians, biophysicists, and computational biologists.
Download or read book Simulating Normal and Arrhythmic Dynamics From Sub Cellular to Tissue and Organ Level written by Hans Dierckx and published by Frontiers Media SA. This book was released on 2019-10-04 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tissue Functioning and Remodeling in the Circulatory and Ventilatory Systems written by Marc Thiriet and published by Springer Science & Business Media. This book was released on 2013-01-11 with total page 976 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volumes in this authoritative series present a multidisciplinary approach to modeling and simulation of flows in the cardiovascular and ventilatory systems, especially multiscale modeling and coupled simulations. Volume 5 is devoted to cells, tissues, and organs of the cardiovascular and ventilatory systems with an emphasis on mechanotransduction-based regulation of flow. The blood vessel wall is a living tissue that quickly reacts to loads applied on it by the flowing blood. In any segment of a blood vessel, the endothelial and smooth muscle cells can sense unusual time variations in small-magnitude wall shear stress and large-amplitude wall stretch generated by abnormal hemodynamic stresses. These cells respond with a short-time scale (from seconds to hours) to adapt the vessel caliber. Since such adaptive cell activities can be described using mathematical models, a key objective of this volume is to identify the mesoscopic agents and nanoscopic mediators required to derive adequate mathematical models. The resulting biomathematical models and corresponding simulation software can be incorporated into platforms developed in virtual physiology for improved understanding and training.
Download or read book Integrative Computational Modeling of Calcium Handling and Cardiac Arrhythmias written by Henry Sutanto and published by Henry Sutanto. This book was released on 2021-01-01 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardiomyocyte calcium handling is a major determinant of excitation-contraction coupling. Alterations in one or more calcium-handling proteins may induce arrhythmias through the formation of ectopic activity, direct and indirect ion-channel regulation, and structural remodeling. Due to the complex and tight interactions between calcium and other molecules within a cardiomyocyte, it remains experimentally challenging to study the exact contributions of calcium-handling abnormalities to arrhythmogenesis. Multiscale computational studies performed in close collaboration with laboratory experiments create new opportunities to unravel the mechanisms of arrhythmogenesis. This thesis describes the roles of integrative computational modeling in unraveling the arrhythmogenic consequences of calcium-handling abnormalities.
Download or read book Mathematical Modeling of Cardiovascular Systems From Physiology to the Clinic written by Julius Guccione and published by Frontiers Media SA. This book was released on 2020-01-13 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cardiac Repolarization written by Ihor Gussak and published by Springer Science & Business Media. This book was released on 2003-03-13 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of all the latest developments in cardiac electrophysiology, focusing on both the clinical and experimental aspects of ventricular repolarization, including newly discovered clinical repolarization syndromes, electrocardiographic phenomena, and their correlation with the most recent advances in basic science. The authors illuminate the basic electrophysiologic, molecular, and pharmacologic mechanisms underlying ventricular repolarization, relate them to specific disease conditions, and examine the future of antiarrhythmic drug development based on both molecular and electrophysiological properties. They also fully review the clinical presentation and management of specific cardiac repolarization conditions.
Download or read book Models of Calcium Signalling written by Geneviève Dupont and published by Springer. This book was released on 2016-06-07 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the ways in which mathematical, computational, and modelling methods can be used to help understand the dynamics of intracellular calcium. The concentration of free intracellular calcium is vital for controlling a wide range of cellular processes, and is thus of great physiological importance. However, because of the complex ways in which the calcium concentration varies, it is also of great mathematical interest.This book presents the general modelling theory as well as a large number of specific case examples, to show how mathematical modelling can interact with experimental approaches, in an interdisciplinary and multifaceted approach to the study of an important physiological control mechanism. Geneviève Dupont is FNRS Research Director at the Unit of Theoretical Chronobiology of the Université Libre de Bruxelles; Martin Falcke is head of the Mathematical Cell Physiology group at the Max Delbrück Center for Molecular Medicine, Berlin; Vivien Kirk is an Associate Professor in the Department of Mathematics at the University of Auckland, New Zealand; James Sneyd is a Professor in the Department of Mathematics at The University of Auckland, New Zealand.
Download or read book Stochastic Methods in Neuroscience written by Carlo Laing and published by Oxford University Press. This book was released on 2010 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: Great interest is now being shown in computational and mathematical neuroscience, fuelled in part by the rise in computing power, the ability to record large amounts of neurophysiological data, and advances in stochastic analysis. These techniques are leading to biophysically more realistic models. It has also become clear that both neuroscientists and mathematicians profit from collaborations in this exciting research area.Graduates and researchers in computational neuroscience and stochastic systems, and neuroscientists seeking to learn more about recent advances in the modelling and analysis of noisy neural systems, will benefit from this comprehensive overview. The series of self-contained chapters, each written by experts in their field, covers key topics such as: Markov chain models for ion channel release; stochastically forced single neurons and populations of neurons; statistical methods for parameterestimation; and the numerical approximation of these stochastic models.Each chapter gives an overview of a particular topic, including its history, important results in the area, and future challenges, and the text comes complete with a jargon-busting index of acronyms to allow readers to familiarize themselves with the language used.
Download or read book Excitation Contraction Coupling and Cardiac Contractile Force written by Donald Bers and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: How is the heartbeat generated? What controls the strength of contraction of heart muscle? What are the links between cardiac structure and function? How does our understanding of skeletal and smooth muscle and non-muscle cells influence our thinking about force development in the heart? Are there important species differences in how contraction is regulated in the heart? How do the new molecular data fit together in understanding the heart beat? What goes wrong in ischemia, hypertrophy, and heart failure? This book paints a modern `portrait' of how the heart works and in this picture the author shows a close-up of the structural, biochemical, and physiological links between excitation and contraction. The author takes the reader through a series of important, interrelated topics with great clarity and continuity and also includes many useful illustrations and tables. The book starts by considering the cellular structures involved in excitation-contraction coupling and then described the characteristics of the myofilaments as the end effector of excitation-contraction coupling. A general scheme of calcium regulation is described and the possible sources and sinks of calcium are discussed in simple, but quantitative terms. The cardiac action potential and its many underlying currents are reviewed. Then the characteristics of some key calcium transport systems (calcium channels, sodium/calcium exchange and SR calcium uptake and release) are discussed in detail. This is then built into a more integrated picture of calcium regulation in succeeding chapters by detailed discussions of excitation-calcium coupling mechanisms (in skeletal, cardiac, and smooth muscle), the interplay between calcium regulatory processes, and finally mechanisms of cardiac inotropy, calcium overload, and dysfunction (e.g., ischemia, hypertrophy, and heart failure). Excitation-Contraction Coupling and Cardiac Contractile Force – Second Edition is an invaluable source of information for anyone who is interested in how the heart beat is controlled and especially suited for students of the cardiovascular system at all levels from medical/graduate students through senior investigators in related fields.
Download or read book Multi Scale Computational Cardiology written by Ling Xia and published by Frontiers Media SA. This book was released on 2022-03-07 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2009 with total page 810 pages. Available in PDF, EPUB and Kindle. Book excerpt:
