The Role Of Hypoxia In Human Health And Disease

The condition characterized by an inadequate supply of oxygen, at the level of tissues, in a region of the body is termed as hypoxia. This can arise due to decreased partial pressures of oxygen, insufficient available hemoglobin, and problems with the diffusion of oxygen in the lungs, breathing rhythm and blood flow. It may be classified as generalized or local. Generalized hypoxia can happen when people ascend to high altitudes, leading to potentially fatal consequences including high altitude cerebral edema and high altitude pulmonary edema. It can also occur when individuals breathe in a mixture of gases with low oxygen content. Hypoxia is a common complication of premature births when the lungs are not fully formed. Within minutes after the symptoms of hypoxia have set in, the brain, liver and other vital organs can be damaged. This book is a valuable compilation of topics, ranging from the basic to the most complex advancements in the understanding of the role of hypoxia in human health and disease. It includes some of the vital pieces of work being conducted across the world, on various topics related to this medical condition. Coherent flow of topics, student-friendly language and extensive use of examples make this book an invaluable source of knowledge.

This book contains a total of 21 chapters, each of which was written by experts in the corresponding field. The objective of this book is to provide a comprehensive and updated overview of cellular and molecular mechanisms underlying hypoxia's impacts on human health, as well as current advances and future directions in the detection, recognition, and management of hypoxia-related disorders. This collection of articles provides a clear update in the area of hypoxia research for biomedical researchers, medical students, nurse practitioners, and practicing clinicians in the fields of high altitude biology, cardiovascular biology and medicine, tumor oncology, obstetrics, pediatrics, and orthodontics and for others who may be interested in hypoxia.

Intermittent hypoxia can cause significant structural and functional impact on the systemic, organic, cellular and molecular processes of human physiology and pathophysiology. This book focuses on the most updated scientific understanding of the adaptive (beneficial) and maladaptive (detrimental) responses to intermittent hypoxia and their potential pathogenetic or prophylactic roles in the development and progression of major human diseases. This is a comprehensive monograph for clinicians, research scientists, academic faculty, postgraduate and medical students, and allied health professionals who are interested in enhancing their up-to-date knowledge of intermittent hypoxia research and its translational applications in preventing and treating major human diseases.

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.

The molecular deprivation of oxygen is manifested by hypoxia, a deficiency of oxygen and anoxia, or the absence of oxygen supply to the tissues. This book entitled Hypoxia and Anoxia will cover a broad range of understanding on hypoxia and anoxia from molecular mechanisms to pathophysiology. Hypoxia and anoxia stimulate multiple systems through specific cell signal transduction pathways and regulate several transcriptional factors like HIF-1, REST to encode genes for VEGF, Epo, etc. This book will also highlight different types of hypoxia and anoxia along with their impact on apoptosis, cardiovascular pathophysiology, and glucose regulatory mechanisms. This book will be a ready reckoner to give a deep understanding of the oxygen-sensing environment in vivo for researchers, academicians, and clinicians throughout the world.

In consolidation of the most updated experimental results and perspectives from diverse research fields on a main theme - Intermittent Hypoxia, this book encompasses the structural, physiological, pathophysiological, biochemical, genetic, metabolic, and therapeutic aspects of intermittent hypoxia and provides an open forum to promote the bench-to-bed translational implications of both adaptive (beneficial) and maladaptive (detrimental) responses to intermittent hypoxia in animals and humans. Authored by 74 leading scientists from 17 countries in Asia, Europe, North America, and Oceana, the 30 chapters are grouped under 7 different sections covering the profound effects of intermittent hypoxia particularly on cardiovascular, respiratory, nervous, and skeletal muscular systems. Special attentions are paid to the protective or injurious roles played by intermittent hypoxia and their underlying cellular and molecular mechanisms in several major human diseases such as acute myocardial infarction, stroke, sleep apnea, and Parkinsons disease. Several chapters have also reviewed the use of intermittent hypoxia training for enhancing exercise performance in elite athletes. Overall, as endorsed by Professor John B. West (Member, Institute of Medicine, National Academy of Sciences of U.S.A.; Editor-in-Chief, High Altitude Medicine and Biology) through his Foreword for the book, this is the most comprehensive monograph to date on the topic of intermittent hypoxia, which can cause significant structural and functional impact on the systemic, organic, cellular and molecular processes of human physiology and pathophysiology. Hence, this book could serve as a thorough reference for research scientists, physicians, academic faculty, graduate and medical students, athletic coaches and trainers, who are interested in enhancing their knowledge about the past, present, and future of intermittent hypoxia research and its translational applications for prevention and treatment of major diseases and improving exercise performance.

This report considers the biological and behavioral mechanisms that may underlie the pathogenicity of tobacco smoke. Many Surgeon General's reports have considered research findings on mechanisms in assessing the biological plausibility of associations observed in epidemiologic studies. Mechanisms of disease are important because they may provide plausibility, which is one of the guideline criteria for assessing evidence on causation. This report specifically reviews the evidence on the potential mechanisms by which smoking causes diseases and considers whether a mechanism is likely to be operative in the production of human disease by tobacco smoke. This evidence is relevant to understanding how smoking causes disease, to identifying those who may be particularly susceptible, and to assessing the potential risks of tobacco products.

The ability of cells to sense and respond to changes in oxygenation underlies a multitude of developmental, physiological, and pathological processes. This volume provides a comprehensive compendium of experimental approaches to the study of oxygen sensing in 48 chapters that are written by leaders in their fields.