The Cerebral Circulation

The Cerebral Circulation

Author: Marilyn J. Cipolla

Publisher: Biota Publishing

Published: 2016-07-28

Total Pages: 82

ISBN-13: 1615047239

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This e-book will review special features of the cerebral circulation and how they contribute to the physiology of the brain. It describes structural and functional properties of the cerebral circulation that are unique to the brain, an organ with high metabolic demands and the need for tight water and ion homeostasis. Autoregulation is pronounced in the brain, with myogenic, metabolic and neurogenic mechanisms contributing to maintain relatively constant blood flow during both increases and decreases in pressure. In addition, unlike peripheral organs where the majority of vascular resistance resides in small arteries and arterioles, large extracranial and intracranial arteries contribute significantly to vascular resistance in the brain. The prominent role of large arteries in cerebrovascular resistance helps maintain blood flow and protect downstream vessels during changes in perfusion pressure. The cerebral endothelium is also unique in that its barrier properties are in some way more like epithelium than endothelium in the periphery. The cerebral endothelium, known as the blood-brain barrier, has specialized tight junctions that do not allow ions to pass freely and has very low hydraulic conductivity and transcellular transport. This special configuration modifies Starling's forces in the brain microcirculation such that ions retained in the vascular lumen oppose water movement due to hydrostatic pressure. Tight water regulation is necessary in the brain because it has limited capacity for expansion within the skull. Increased intracranial pressure due to vasogenic edema can cause severe neurologic complications and death.


The Endothelium

The Endothelium

Author: Michel Félétou

Publisher: Morgan & Claypool Publishers

Published: 2011

Total Pages: 309

ISBN-13: 1615041230

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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


Regulation of Tissue Oxygenation, Second Edition

Regulation of Tissue Oxygenation, Second Edition

Author: Roland N. Pittman

Publisher: Biota Publishing

Published: 2016-08-18

Total Pages: 117

ISBN-13: 1615047212

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This presentation describes various aspects of the regulation of tissue oxygenation, including the roles of the circulatory system, respiratory system, and blood, the carrier of oxygen within these components of the cardiorespiratory system. The respiratory system takes oxygen from the atmosphere and transports it by diffusion from the air in the alveoli to the blood flowing through the pulmonary capillaries. The cardiovascular system then moves the oxygenated blood from the heart to the microcirculation of the various organs by convection, where oxygen is released from hemoglobin in the red blood cells and moves to the parenchymal cells of each tissue by diffusion. Oxygen that has diffused into cells is then utilized in the mitochondria to produce adenosine triphosphate (ATP), the energy currency of all cells. The mitochondria are able to produce ATP until the oxygen tension or PO2 on the cell surface falls to a critical level of about 4–5 mm Hg. Thus, in order to meet the energetic needs of cells, it is important to maintain a continuous supply of oxygen to the mitochondria at or above the critical PO2 . In order to accomplish this desired outcome, the cardiorespiratory system, including the blood, must be capable of regulation to ensure survival of all tissues under a wide range of circumstances. The purpose of this presentation is to provide basic information about the operation and regulation of the cardiovascular and respiratory systems, as well as the properties of the blood and parenchymal cells, so that a fundamental understanding of the regulation of tissue oxygenation is achieved.


Regulation of Coronary Blood Flow

Regulation of Coronary Blood Flow

Author: Michitoshi Inoue

Publisher: Springer Science & Business Media

Published: 2013-11-09

Total Pages: 330

ISBN-13: 4431683674

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Research centering on blood flow in the heart continues to hold an important position, especially since a better understanding of the subject may help reduce the incidence of coronary arterial disease and heart attacks. This book summarizes recent advances in the field; it is the product of fruitful cooperation among international scientists who met in Japan in May, 1990 to discuss the regulation of coronary blood flow.


Inflammation and the Microcirculation

Inflammation and the Microcirculation

Author: D. Neil Granger

Publisher: Morgan & Claypool Publishers

Published: 2010

Total Pages: 99

ISBN-13: 1615041656

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The microcirculation is highly responsive to, and a vital participant in, the inflammatory response. All segments of the microvasculature (arterioles, capillaries, and venules) exhibit characteristic phenotypic changes during inflammation that appear to be directed toward enhancing the delivery of inflammatory cells to the injured/infected tissue, isolating the region from healthy tissue and the systemic circulation, and setting the stage for tissue repair and regeneration. The best characterized responses of the microcirculation to inflammation include impaired vasomotor function, reduced capillary perfusion, adhesion of leukocytes and platelets, activation of the coagulation cascade, and enhanced thrombosis, increased vascular permeability, and an increase in the rate of proliferation of blood and lymphatic vessels. A variety of cells that normally circulate in blood (leukocytes, platelets) or reside within the vessel wall (endothelial cells, pericytes) or in the perivascular space (mast cells, macrophages) are activated in response to inflammation. The activation products and chemical mediators released from these cells act through different well-characterized signaling pathways to induce the phenotypic changes in microvessel function that accompany inflammation. Drugs that target a specific microvascular response to inflammation, such as leukocyte-endothelial cell adhesion or angiogenesis, have shown promise in both the preclinical and clinical studies of inflammatory disease. Future research efforts in this area will likely identify new avenues for therapeutic intervention in inflammation. Table of Contents: Introduction / Historical Perspectives / Anatomical Considerations / Impaired Vasomotor Responses / Capillary Perfusion / Angiogenesis / Leukocyte-Endothelial Cell Adhesion / Platelet-Vessel Wall Interactions / Coagulation and Thrombosis / Endothelial Barrier Dysfunction / Epilogue / References


Textbook of Aging Skin

Textbook of Aging Skin

Author: Miranda A. Farage

Publisher: Springer Science & Business Media

Published: 2009-12-02

Total Pages: 1255

ISBN-13: 3540896554

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This comprehensive ‘Major Reference Book’ compiles all current and latest information on aging skin in a two-volume set. Highly structured with a reader-friendly format, it covers a wide range of areas such as basic sciences, the different diseases and conditions which occur with aging (from malignant to non-malignant), the latest techniques and methods being used such as bioengineering methods and biometrics as well as toxicological and safety considerations for the elderly population. It also illustrates the global consumers’ sociological and psychological implications, ethnicity and gender differences and includes marketing considerations for this elderly group. This unique and comprehensive guide will become the main reference textbook on this topic.


Dynamic Aspects of Dental Pulp

Dynamic Aspects of Dental Pulp

Author: Reizo Inoki

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 503

ISBN-13: 9400904215

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This book presents a circumspective overview and update of the present existing knowledge of the biology, chemistry and pathophysiology of the dental pulp. It details numerous observations of a group of highly specialized investigators who have united in the common purpose of presenting their observations for the benefit of clinicians, teachers, researchers and students. Fortunately, the dental literature presents abundant research findings about pulp biology and the pulp's responses to various stimuli. This abundance has resulted in an increased interest and expansion of research on this subject. For example, publications abound on the response of pulp tissue to various medications and to a variety of types of dental materials which may be placed near to or at some distance from the pulp through the medium of dentine. One of the reasons the pulp is of such interest is that it not only provides the vitality to the teeth but also produces the dentine - both the primary and secondary, as well as reparative. The latter-type dentine is a result of the pulp's functions in response to disease as the former dentine is in response to health. As an example, some investigators have reported the effects of cutting of dentine and the placement of restorations in dentine which in turn reflect changes on the pulp tissue. These reports have raised a number of questions, which in turn have created a need for answers.


ABC of Hypertension

ABC of Hypertension

Author: D. Gareth Beevers

Publisher: John Wiley & Sons

Published: 2010-07-15

Total Pages: 89

ISBN-13: 1405171359

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Hypertension is a condition which affects millions of peopleworldwide and its treatment greatly reduces the risk of strokes andheart attacks. This fully revised and updated edition of the ABCof Hypertension is an established guide providing all thenon-specialist needs to know about the measurement of bloodpressure and the investigation and management of hypertensivepatients. This new edition provides comprehensively updated andrevised information on how and whom to treat. The ABC of Hypertension will prove invaluable to generalpractitioners who may be screening large numbers of patients forhypertension, as well as nurse practitioners, midwives and otherhealthcare professionals.


Regulation of Endothelial Barrier Function

Regulation of Endothelial Barrier Function

Author: Sarah Y. Yuan

Publisher: Biota Publishing

Published: 2011-02-01

Total Pages: 160

ISBN-13: 1615041214

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The vascular endothelium lining the inner surface of blood vessels serves as the first interface for circulating blood components to interact with cells of the vascular wall and surrounding extravascular tissues. In addition to regulating blood delivery and perfusion, a major function of vascular endothelia, especially those in exchange microvessels (capillaries and postcapillary venules), is to provide a semipermeable barrier that controls blood–tissue exchange of fluids, nutrients, and metabolic wastes while preventing pathogens or harmful materials in the circulation from entering into tissues. During host defense against infection or tissue injury, endothelial barrier dysfunction occurs as a consequence as well as cause of inflammatory responses. Plasma leakage disturbs fluid homeostasis and impairs tissue oxygenation, a pathophysiological process contributing to multiple organ dysfunction associated with trauma, infection, metabolic disorder, and other forms of disease. In this book, we provide an updated overview of microvascular endothelial barrier structure and function in health and disease. The discussion is initiated with the basic physiological principles of fluid and solute transport across microvascular endothelium, followed by detailed information on endothelial cell–cell and cell–matrix interactions and the experimental techniques that are employed to measure endothelial permeability. Further discussion focuses on the signaling and molecular mechanisms of endothelial barrier responses to various stimulations or drugs, as well as their relevance to several common clinical conditions. Taken together, this book provides a comprehensive analysis of microvascular endothelial cell and molecular pathophysiology. Such information will assist scientists and clinicians in advanced basic and clinical research for improved health care.


Coronary Microvascular Dysfunction

Coronary Microvascular Dysfunction

Author: Filippo Crea

Publisher: Springer Science & Business Media

Published: 2013-08-15

Total Pages: 263

ISBN-13: 8847053676

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In the past two decades a number of studies have shown that abnormalities in the function and structure of coronary microcirculation can be detected in several cardiovascular diseases. On the basis of the clinical setting in which it occurs, coronary microvascular dysfunction (CMD) can be classified into four types: CMD in the absence of any other cardiac disease; CMD in myocardial diseases; CMD in obstructive epicardial coronary artery disease; and iatrogenic CMD. In some instances CMD represents an epiphenomenon, whereas in others it represents an important marker of risk or may contribute to the pathogenesis of myocardial ischemia, thus becoming a possible therapeutic target. This book provides an update on coronary physiology and a systematic assessment of microvascular abnormalities in cardiovascular diseases, in the hope that it will assist clinicians in prevention, detection and management of CMD in their everyday activity.