Three distinct types of contractions perform colonic motility functions. Rhythmic phasic contractions (RPCs) cause slow net distal propulsion with extensive mixing/turning over. Infrequently occurring giant migrating contractions (GMCs) produce mass movements. Tonic contractions aid RPCs in their motor function. The spatiotemporal patterns of these contractions differ markedly. The amplitude and distance of propagation of a GMC are several-fold larger than those of an RPC. The enteric neurons and smooth muscle cells are the core regulators of all three types of contractions. The regulation of contractions by these mechanisms is modifiable by extrinsic factors: CNS, autonomic neurons, hormones, inflammatory mediators, and stress mediators. Only the GMCs produce descending inhibition, which accommodates the large bolus being propelled without increasing muscle tone. The strong compression of the colon wall generates afferent signals that are below nociceptive threshold in healthy subjects. However, these signals become nociceptive; if the amplitudes of GMCs increase, afferent nerves become hypersensitive, or descending inhibition is impaired. The GMCs also provide the force for rapid propulsion of feces and descending inhibition to relax the internal anal sphincter during defecation. The dysregulation of GMCs is a major factor in colonic motility disorders: irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and diverticular disease (DD). Frequent mass movements by GMCs cause diarrhea in diarrhea predominant IBS, IBD, and DD, while a decrease in the frequency of GMCs causes constipation. The GMCs generate the afferent signals for intermittent short-lived episodes of abdominal cramping in these disorders. Epigenetic dysregulation due to adverse events in early life is one of the major factors in generating the symptoms of IBS in adulthood.

This fully revised new edition focuses on the clinical, diagnostic, and therapeutic aspects of conditions encountered by the coloproctologist and gastroenterological surgeon, who are faced with an increasing number of precise and specific treatment modalities.

This open access book deals with imaging of the abdomen and pelvis, an area that has seen considerable advances over the past several years, driven by clinical as well as technological developments. The respective chapters, written by internationally respected experts in their fields, focus on imaging diagnosis and interventional therapies in abdominal and pelvic disease; they cover all relevant imaging modalities, including magnetic resonance imaging, computed tomography, and positron emission tomography. As such, the book offers a comprehensive review of the state of the art in imaging of the abdomen and pelvis. It will be of interest to general radiologists, radiology residents, interventional radiologists, and clinicians from other specialties who want to update their knowledge in this area.

This first reference to comprehensively address both the medical and surgical management of diseases affecting the colon, this source spans the wide array of colorectal disorders including rectal prolapse, irritable bowel syndrome, benign and malignant colonic tumors, fissures and ulcers, and Crohn's colitis, among other ailments. With chapters by

Interventional Inflammatory Bowel Diseases: Endoscopic Management and Treatment of Complications covers the preparation, principle, techniques, and damage control of complications in endoscopic therapy, providing the ultimate guidance in endoscopic management of IBD. With contributions from a panel of international leading experts in the field, perspectives are included from GI pathologists, GI radiologists, gastroenterologists, advanced endoscopists, IBD specialists and colorectal surgeons. Recommendations from experts are also included within each chapter. By bridging medical and surgical treatment modalities for IBD, this is the perfect reference for GI researchers, medical students, therapeutic GI endoscopists, IBD specialists, surgeons and advanced health care providers. - Incorporates state-of-the-art of research in the area of therapeutic endoscopy in Crohn's Disease and Ulcerative Colitis - Makes the connection between the understanding of the complex nature and disease course of IBD with corresponding advanced endoscopic procedures - Explores endoscopic treatment as the missing link between medical and surgical treatment for complex Crohn's Disease and Ulcerative Colitis - Contains access to videos demonstrating important procedural concepts

This book reviews the microbiology of the human gastrointestinal tract and how its composition and activities may affect host welfare. Drawing on the expertise of internationally recognised authors, a comprehensive account of gut microbiology is given. In particular, the nature of the microbiota, the fermentation process, gut flora modulation through diet (probiotics, prebiotics), molecular approaches for studying the bacteria, health outcomes associated with colonic microbial function and consumer aspects are all detailed. It is now believed that gut function, and colonic bacteria specifically, can play an important role in human nutrition and health. Whilst it has long been realised that the gastrointestinal microbiota can affect host well-being, the full extent of this interaction is only now emerging. This book gives a balanced review of current knowledge on how gut flora can be optimised for improved health and on some of the more important target outcomes. Its contents will therefore be of topical relevance to scientists and students involved in microbiology, gastroenterology, nutrition and the food industry.

The Scientification of Gastroenterology During the 20th Century * Science contributes to medicine in three ways: It provides a body of relatively secure knowl edge. Some of that knowledge has been applied to develop technologies which have had a major impact upon the practice and effectiveness of medicine. Last, science offers to medicine a way of thinking. - 1. McCormick [(1993) The Contribution of Science to Medicine. Perspect. Bioi. Med. 16,315.] Awareness of the digestive system began with the dawn of civilization, when man, observing the feeding habits of animals in the surrounding environment, experimented with foods, edible and inedible. Identity came with discoveries of the digestive organs during the 16th and 17th centuries. Function was revealed by physiologic studies of digestion, absorp tion and secretion, metabolism, and motility during the 18th and 19th centuries. Diagnostic access improved with the technological advances of the 20th century. Understanding of gas trointestinal (GI) disease followed the growth of the basic sciences and gastroenterology's involvement in scientific research during the latter half of the 20th century. Early in the 20th century, gastroenterology was yet an undefined activity without clinical or scientific guidelines. Diagnostic approach to the digestive tract was minimal. Valid con cepts of disease were lacking. Visceroptosis, sitophobia, and "colonic autointoxication" were common "diagnoses." Therapeutic resources were scarce.