The mammalian gastrointestinal mucosa is a rapidly self-renewing tissue in the body, and its homeostasis is preserved through the strict regulation of epithelial cell proliferation, growth arrest, and apoptosis. The control of the growth of gastrointestinal mucosa is unique and, compared with most other tissue in the body, complex. Mucosal growth is regulated by the same hormones that alter metabolism in other tissues, but the gastrointestinal mucosa also responds to host events triggered by the ingestion and presence of food within the digestive tract. These gut hormones and peptides regulate the growth of the exocrine pancreas, gallbladder epithelium, and the mucosa of the oxyntic gland region of the stomach and the small and large intestines. Luminal factors, including nutrients or other dietary factors, secretions, and microbes that occur within the lumen and distribute over a proximal-to-distal gradient, are also crucial for maintenance of normal gut mucosal regeneration and could explain the villous-height-crypt-depth gradient and variety of adaptation, since these factors are diluted, absorbed, and destroyed as they pass down the digestive tract. Recently, intestinal stem cells, cellular polyamines, and noncoding RNAs are shown to play an important role in the regulation of gastrointestinal mucosal growth under physiological and various pathological conditions. In this book, we highlight key issues and factors that control gastrointestinal mucosal growth and homeostasis, with special emphasis on the mechanisms through which epithelial renewal and apoptosis are regulated at the cellular and molecular levels.

Gastrointestinal Tissue: Oxidative Stress and Dietary Antioxidants brings together leading experts from world renowned institutions, combining the basic mechanisms of gastrointestinal diseases with information regarding new and alternative treatments. The processes within the science of oxidative stress are described in concert with other processes, including apoptosis, cell signaling and receptor mediated responses, further recognizing that diseases are often multifactorial with oxidative stress as a component. By combining the critical molecular processes underlying free radical mediated pathologies and the role of dietary antioxidant molecules, a connection is made that helps advance therapies and the prevention of gastrointestinal pathological processes. This important reference is well designed with two complementary sections. Section One, Oxidative Stress and Gastroenterology, covers the basic processes of oxidative stress from molecular biology to whole organs, the gastrointestinal anatomy and sources of oxidative stress and free radicals and their products in gastrointestinal diseases. Section Two, Antioxidants and Gastroenterology covers antioxidants in foods, including plants and components. - Covers the science of oxidative stress in gastrointestinal tissue and associated conditions and scenarios - Provides information on optimal levels for human consumption of antioxidants, suggested requirements per day, recommended dietary allowances and curative/preventive effects of dietary antioxidants - Presents an easy to reference guide with two complementary sections that discuss the pathophysiology of gastrointestinal diseases in relation to oxidative stress and antioxidant therapies

The microcirculation of the gastrointestinal tract is under the control of both myogenic and metabolic regulatory systems. The myogenic mechanism contributes to basal vascular tone and the regulation of transmural pressure, while the metabolic mechanism is responsible for maintaining an appropriate balance between O2 demand and O2 delivery. In the postprandial state, hydrolytic products of food digestion elicit a hyperemia, which serves to meet the increased O2 demand of nutrient assimilation. Metabolically linked factors (e.g., tissue pO2, adenosine) are primarily responsible for this functional hyperemia. The fenestrated capillaries of the gastrointestinal mucosa are relatively permeable to small hydrolytic products of food digestion (e.g., glucose), yet restrict the transcapillary movement of larger molecules (e.g., albumin). This allows for the absorption of hydrolytic products of food digestion without compromising the oncotic pressure gradient governing transcapillary fluid movement and edema formation. The gastrointestinal microcirculation is also an important component of the mucosal defense system whose function is to prevent (and rapidly repair) inadvertent epithelial injury by potentially noxious constituents of chyme. Two pathological conditions in which the gastrointestinal circulation plays an important role are ischemia/reperfusion and chronic portal hypertension. Ischemia/reperfusion results in mucosal edema and disruption of the epithelium due, in part, to an inflammatory response (e.g., increase in capillary permeability to macromolecules and neutrophil infiltration). Chronic portal hypertension results in an increase in gastrointestinal blood flow due to an imbalance in vasodilator and vasoconstrictor influences on the microcirculation. Table of Contents: Introduction / Anatomy / Regulation of Vascular Tone and Oxygenation / Extrinsic Vasoregulation: Neural and Humoral / Postprandial Hyperemia / Transcapillary Solute Exchange / Transcapillary Fluid Exchange / Interaction of Capillary and Interstitial Forces / Gastrointestinal Circulation and Mucosal Defense / Gastrointestinal Circulation and Mucosal Pathology I: Ischemia/Reperfusion / Gastrointestinal Circulation and Mucosal Pathology II: Chronic Portal Hypertension / Summary and Conclusions / References / Author Biography

Translational Regenerative Medicine is a reference book that outlines the life cycle for effective implementation of discoveries in the dynamic field of regenerative medicine. By addressing science, technology, development, regulatory, manufacturing, intellectual property, investment, financial, and clinical aspects of the field, this work takes a holistic look at the translation of science and disseminates knowledge for practical use of regenerative medicine tools, therapeutics, and diagnostics. Incorporating contributions from leaders in the fields of translational science across academia, industry, and government, this book establishes a more fluid transition for rapid translation of research to enhance human health and well-being. - Provides formulaic coverage of the landscape, process development, manufacturing, challenges, evaluation, and regulatory aspects of the most promising regenerative medicine clinical applications - Covers clinical aspects of regenerative medicine related to skin, cartilage, tendons, ligaments, joints, bone, fat, muscle, vascular system, hematopoietic /immune system, peripheral nerve, central nervous system, endocrine system, ophthalmic system, auditory system, oral system, respiratory system, cardiac system, renal system, hepatic system, gastrointestinal system, genitourinary system - Identifies effective, proven tools and metrics to identify and pursue clinical and commercial regenerative medicine

The gastrointestinal tract is a long, muscular tube responsible for the digestion of food, assimilation of nutrients and elimination of waste. This is achieved by secretion of digestive enzymes and absorption from the intestinal lumen, with different regions playing specific roles in the processing of specific nutrients. These regions come into play sequentially as ingested material is moved along the length of the GI tract by contractions of the muscle layers. In some regions like the oesophagus transit it rapid and measured in seconds while in others like the colon transit is measured in hours and even days, commensurate with the relative slow fermentation that takes place in the large bowel. An hierarchy of controls, neural and endocrine, serve to regulate the various cellular targets that exist in the gut wall. These include muscle cells for contraction and epithelial cells for secretion and absorption. However, there are complex interactions between these digestive mechanisms and other mechanisms that regulate blood flow, immune function, endocrine secretion and food intake. These ensure a fine balance between the ostensibly conflicting tasks of digestion and absorption and protection from potentially harmful ingested materials. They match assimilation of nutrients with hunger and satiety and they ensure that regions of the GI tract that are meters apart work together in a coordinated fashion to match these diverse functions to the digestive needs of the individual. This ebook will provide an overview of the neural mechanisms that control gastrointestinal function. Table of Contents: Neural Control of Gastrointestinal Function / Cells and Tissues / Enteric Nervous System / From Gut to CNS: Extrinsic Sensory Innervation / Sympathetic Innervation of the Gut / Parasympathetic Innervation of the Gut / Integration of Function / References

This book offers one of the most comprehensive reviews in the field of gastrointestinal (GI) physiology, guiding readers on a journey through the complete digestive tract, while also highlighting related organs and glandular systems. It is not solely limited to organ system physiology, and related disciplines like anatomy and histology, but also examines the molecular and cellular processes that keep the digestive system running. As such, the book provides extensive information on the molecular, cellular, tissue, organ, and system levels of functions in the GI system. Chapters on the roles of the gut as an endocrine, exocrine and neural organ, as well as its microbiome functions, broaden readers’ understanding of the multi-organ networks in the human body. To help illustrate the interconnections between the physiological concepts, principles and clinical presentations, it outlines clinical examples such as pathologies that link basic science with clinical practice in special “clinical correlates” sections. Covering both traditional and contemporary topics, it is a valuable resource for biomedical students, as well as healthcare and scientific professionals.