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.
It is now recognized that defective placentation in the human is a cause of many pregnancy complications, such as spontaneous abortion, preterm labor and delivery, pre-eclampsia, intrauterine growth restriction, fetal death and abruptio placenta. These clinical disorders can often have long-term consequences into adulthood, causing cardiovascular disease, obesity and diabetes for the newborn as well as an increased risk of premature death in the mother. This is the first book to be entirely focused on the placental bed, bringing together the results of basic and clinical research in cell biology, immunology, endocrinology, pathology, genetics and imaging to consolidate in a single, informative source for investigators and clinicians. Its core aim is to explore new approaches and improve current clinical practice. This is essential reading for clinicians in obstetric, cardiovascular and reproductive medicine.
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.
Respiratory diseases affect a large proportion of the population and can cause complications when associated with pregnancy. Pregnancy induces profound anatomical and functional physiological changes in the mother, and subjects the mother to pregnancy-specific respiratory conditions. Reviewing respiratory conditions both specific and non-specific to pregnancy, the book also addresses related issues such as smoking and mechanical ventilation. Basic concepts for the obstetrician are covered, including patient history, physiology and initial examinations. Topics such as physiological changes during pregnancy and placental gas exchange are discussed for the non-obstetrician. Guidance is practical, covering antenatal and post-partum care, as well as management in the delivery suite. An essential guide to respiratory diseases in pregnancy, this book is indispensable to both obstetricians and non-obstetric physicians managing pregnant patients.
The optimal function of the placenta and thus fetal well being largely depends upon the integrity of both the fetal and maternal circulations of the placenta. Intense basic research concerned with placental vascularization and blood flow has been performed for the past 30 years, beginning with the classical morphological descriptions of the placental vessels by Boe (1953) and Arts (1961), as well as with the radioangiographic studies of maternal placental circulation in the human by Borell (1958) and in the rhesus monkey by Ramsey (1962). The scientific framework presented by these investigators has been filled and completed by numerous investigators, leading to more morphological details, functional considerations, and pathological understanding. For an extended period of time, this research has been of primarily academic interest by increasing our insights into one important system of the placenta, yet having nearly no practical importance. Recently, this situation has changed dramatically: in vitro studies of the isolated, dually perfused human placenta and in vivo studies of placental circulation for diagnostic purposes have raised an enormous interest in basic research data. New methods like Doppler Ultrasound and NMR became available. These technics have enabled the obstetrician to study fetal and placental hemodynamics in vivo. Meanwhile, such methods are becoming incorporated into the daily obstetrical routine, to some degree without an adequate background knowledge of placental vascularization and blood flow, since such experience is currently available to only a small group of experts.
A comprehensive, cutting-edge review of the complex interactions between maternal and fetal-placental tissues that control the establishment and maintenance of pregnancy, the proper development of the fetus, the birth process, and the behavioral aspects of bonding between mother and newborn. Expert researchers review the endocrine and physiological events that culminate in the delivery of offspring, and provide a solid base of comparative information on the menstrual cycle of primates, including humans. They also discuss the sources and functions of both steroid and protein hormones from the placenta and the details of their effects on uterine function, placental development, fetal growth and well-being, and maternal responses to pregnancy. This book will become the standard reference source not only for reproductive scientists, but also for those clinicians who want better to understand the complex factors that affect pregnancy-and their pregnant patients.
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.
The placenta is fascinating and complex. Basically foreign to the maternal body, it can be thought of as an organ transplanted onto the mother's host tissue. As such it embodies all the principles of tissue acceptance and rejection. Many of the risks of pregnancy and labor have now been eliminated and the placenta is likely to be at the root of many of the dangers to the unborn child that remain. A breakdown of the relationship between the placenta and the maternal tissue may turn out to be the cause of the majority of early lost pregnancies.
The Hepatic circulation is unique among vascular beds. The most obvious unique features include the dual vascular supply; the mechanism of intrinsic regulation of the hepatic artery (the hepatic arterial buffer response); the fact that portal blood flow, supplying two thirds of liver blood flow, is not controlled directly by the liver; the fact that 20% of the cardiac output rushes through the most vascularized organ in the body, driven by a pressure gradient of only a few millimeters of mercury; the extremely distensible capacitance and venous resistance sites; the unidirectional acinar blood flow that regulates parenchymal cell metabolic specialization; and the high concentration of macrophagic (Kupffer) cells filtering the blood. The liver is the only organ reported to have regional blood flow monitored by the autonomic nervous system. This mechanism, when dysfunctional, accounts for the hepatorenal syndrome and offers a mechanistic therapeutic target to treat this syndrome. The trigger for liver regeneration is dependent on hepatic hemodynamics so that chronic liver blood flow regulates liver cell mass. In severe liver disease, the whole body circulation is reorganized, by forming portacaval shunts, to accommodate the increased intrahepatic venous resistance. These shunts protect the venous drainage of the splanchnic organs but lead to loss of major regulatory roles of the liver. The development of knowledge of the hepatic vasculature is presented from a historical perspective with modern concepts summarized based on the perspective of the author's four decades of devotion to this most marvelous of organs. Table of Contents: Acknowledgements / Historical Perspectives / Overview / Fluid Exchange / Capacitance / Resistance in the Hepatic Artery / Resistance in the Venous System / Fetal and Neonatal Hepatic Circulation / In Vivo Pharmacodynamic Approaches / Nitric Oxide / Adenosine / Hepatic Nerves / Hepatic Circulation and Toxicology / Hepatorenal Syndrome / Integrative Hepatic Response to Hemorrhage / Blood Flow Regulation of Hepatocyte Proliferation / Multiple Mechanisms Maintaining a Constant Hepatic Blood Flow to Liver Mass Ratio / Pathopharmacology and Repurposing Drugs as a Research Strategy / References
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
