Author: Win Min Tun
Publisher:
ISBN:
Category : Fetus
Languages : en
Pages : 223
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Book Description
The placenta is an essential organ for a successful pregnancy as it develops to establish effective fetal and maternal blood supplies and materno-fetal gas exchange, both of which are crucial for fetal growth. Abnormal development of the structural components of the placenta are known to be associated with pregnancy complications including fetal growth restriction (FGR) and pre-eclampsia. The overall aim of this thesis is to understand how the placental structural aberrations observed in FGR pregnancies impact placental haemodynamics and materno-fetal gas exchange. In order to accomplish this aim, both in silico and in vitro experimental models are employed to analyse the interactions between placental structure and function in normal and FGR pregnancies.The thesis commences with an in silico study which aims to predict how the structure of the placenta impacts on the mechanical shear stress sensed by endothelial cells that form the walls of placental capillaries. A computational model of feto-placental circulation,with structure parameterised with previously published morphometric data from normal and FGR pregnancies, was used to predict placental microvascular blood flow and shear stress in normal and FGR placentae. The model predicts an elevated microvascular shear stress in FGR placentae in comparison to normal placentae and that the main parameters influencing the elevated shear stress in FGR placentae are placental volume, vascular density, radius and length of individual vascular branches. Shear stress cannot be directly measured in vivo, however, the anatomical model of the placenta considered here provides the first predictions of the magnitude and distribution of shear stress in normal and FGR placentae. The next step is to determine whether this mechanical stress can impact on endothelial cell behaviours. Using an in vitro shear stress experiment, the predicted placental microvascular shear stresses were applied to vascular endothelial cells. These endothelial cells migrated more slowly and more persistently when they were exposed to the shear stresses of FGR conditions, suggesting that normal function of endothelial cells is impaired in FGR placentae, compromising the process of blood vessel formation. We, therefore, propose a vicious cycle in FGR pregnancy, where the elevated shear stress resulting from abnormal vascular structure undermines blood vessel formation, aggravating pre-existing vascular structure abnormalities. The morphology based feto-placental haemodynamic model is extended in two ways. First the model is extended to provide a complete model of the entire fetal circulation. This allows prediction of scenarios relevant to fetal survival in a multi-scale approach, including the interaction between fetal blood pressures, cardiac output and the shear stress in the placental capillaries. Using data from the literature we explore the impact of placental resistance due to structural abnormalities on fetal cardiac function. Then, we take steps toward a personalised approach to modelling the feto-placental circulation by analysing the chorionic vascular network in normal and FGR placentae. We confirm that this network contributes to overall placental resistance in individuals, and quantify how the characteristics of this network impact on placental function in FGR. Finally, in order to understand how the placental villous structure affects on placental exchange function, a 3D computational model of placenta representing the whole organ has been developed. Normal and FGR villous structure were parameterised as reported in previous morphometric studies. The reduced villous density in FGR placentae negatively impacts the maternal blood flow velocity into intervillous space (IVS), resulting in impaired materno-fetal gas exchange and fetal growth.This thesis demonstrates the influence of placental villous and vascular structure on placental vascular shear stress and materno-fetal oxygen exchange, and contributes to the understanding of the pathophysiology of fetal growth in FGR pregnancies. It provides a concept that the in vivo physiological data, that are difficult to assess, could be predicted by developing a replica of biological system computationally.
Author: Yuping Wang
Publisher: Biota Publishing
ISBN: 1615047514
Category : Medical
Languages : en
Pages : 126
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Book Description
The placenta is an organ that connects the developing fetus to the uterine wall, thereby allowing nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. Proper vascular development in the placenta is fundamental to ensuring a healthy fetus and successful pregnancy. This book provides an up-to-date summary and synthesis of knowledge regarding placental vascular biology and discusses the relevance of this vascular bed to the functions of the human placenta.
Author:
Publisher: Academic Press
ISBN: 0128096217
Category : Science
Languages : en
Pages : 350
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Book Description
Piezo Channels, Volume 79, the latest volume in the Current Topics in Membranes series provides the necessary membrane research to assist readers in discovering the current state of a particular field and future directions. New chapters in the updated volume include A Tour de Force: The Discovery, Properties, and Function of Piezo Channels, Piezo1 Channels in Vascular Development and the Sensing of Shear Stress, the Origin of the Force: The Force-From-Lipids Principle Applied to Piezo Channels, Genetic Diseases of PIEZO1 and PIEZO2 Dysfunction, and The Structural Basis for Sensing by the Piezo1 Protein. Users of this series will find an up-to-date presentation of the current knowledge in the field of Piezo Channels. Written by leading experts in the field Contains original material, both textual and illustrative, that make it a very relevant reference Presented in a very comprehensive manner Ideal reference for both researchers in the field and general readers who will find this book to be relevant and up-to-date
Author: Frederick T. Kraus
Publisher:
ISBN:
Category : Medical
Languages : en
Pages : 360
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Book Description
Divided into fourteen chapters and an appendix and with 490 illustrations, this volume includes the structure and function of the normal placenta before reviewing the major disorders and lesions which occur as complications of a normal pregnancy and delivery. It provides an expert comprehensive review of diseases of the placenta.
Author: Raymond W. Redline
Publisher: Cambridge University Press
ISBN: 1316632539
Category : Medical
Languages : en
Pages : 367
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Book Description
A guide to identifying disease processes in the placenta affecting pregnancy outcome, with current diagnostic criteria and clinical consequences.
Author: Christoph Lees
Publisher: Cambridge University Press
ISBN: 1108548180
Category : Medical
Languages : en
Pages : 300
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Book Description
Master the effective evaluation, analysis and management of placental-fetal growth restriction (PFGR), reducing the risk of perinatal mortality and morbidity in patients worldwide. Extensively researched by international experts, this manual provides practitioners with a detailed, hands-on approach to the practical 'pearls' for direct patient management. This authoritative volume advises on matters such as the correct evaluation and management of high-risk patients in danger of PFGR through to delivery. Extensive and wide-ranging, this book is an invaluable companion to the developing research interest and clinical applications in PFGR, including developmental outcomes in early childhood. Featuring a critical evaluation of a variety of abnormal conditions, such as fetal hypoxia, which are clearly displayed through extensive illustrations. This essential toolkit ensures that practitioners of all levels can effectively limit the risk of mortality and morbidity, and reach the correct diagnosis, first-time.
Author: Michel Félétou
Publisher: Morgan & Claypool Publishers
ISBN: 1615041230
Category : Science
Languages : en
Pages : 309
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Book Description
The endothelium, a monolayer of endothelial cells, constitutes the inner cellular lining of the blood vessels (arteries, veins and capillaries) and the lymphatic system, and therefore is in direct contact with the blood/lymph and the circulating cells. The endothelium is a major player in the control of blood fluidity, platelet aggregation and vascular tone, a major actor in the regulation of immunology, inflammation and angiogenesis, and an important metabolizing and an endocrine organ. Endothelial cells controls vascular tone, and thereby blood flow, by synthesizing and releasing relaxing and contracting factors such as nitric oxide, metabolites of arachidonic acid via the cyclooxygenases, lipoxygenases and cytochrome P450 pathways, various peptides (endothelin, urotensin, CNP, adrenomedullin, etc.), adenosine, purines, reactive oxygen species and so on. Additionally, endothelial ectoenzymes are required steps in the generation of vasoactive hormones such as angiotensin II. An endothelial dysfunction linked to an imbalance in the synthesis and/or the release of these various endothelial factors may explain the initiation of cardiovascular pathologies (from hypertension to atherosclerosis) or their development and perpetuation. Table of Contents: Introduction / Multiple Functions of the Endothelial Cells / Calcium Signaling in Vascular Cells and Cell-to-Cell Communications / Endothelium-Dependent Regulation of Vascular Tone / Conclusion / References
Author: Graham J. Burton
Publisher: Cambridge University Press
ISBN: 1139494228
Category : Medical
Languages : en
Pages : 267
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Book Description
Developmental programming is a rapidly advancing discipline of great importance to basic scientists and health professionals alike. This text integrates, for the first time, contributions from world experts to explore the role of the placenta in developmental programming. The book considers the materno-fetal supply line, and how perturbations of placental development impact on its functional capacity. Chapters examine ways in which environmental, immunological and vascular insults regulate expression of conventional and imprinted genes, along with their impact on placental shape and size, transport, metabolism and endocrine function. Research in animal models is integrated with human clinical and epidemiological data, and questions for future research are identified. Transcripts of discussions between the authors allow readers to engage with controversial issues. Essential reading for researchers in placental biology and developmental programming, as well as specialists and trainees in the wider field of reproductive medicine.
Author: Vicki Clark
Publisher: Oxford University Press
ISBN: 0198713339
Category : Medical
Languages : en
Pages : 1017
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Book Description
This textbook provides an up-to-date summary of the scientific basis, assessment for and provision of anaesthesia throughout pregnancy and labour. It is divided into nine sections including physiology, assessment, complications and systemic disease.
Author: Christoph Lees
Publisher: Cambridge University Press
ISBN: 1107157374
Category : Medical
Languages : en
Pages : 281
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Book Description
Discover new concepts in cardiovascular and hemodynamic functionality in feto-maternal medicine, from leading experts in the field.
