摘要:

Advances in the basic science technologies (monoclonal antibodies, polymerase chain reaction, and molecular genetic techniques) have lead to more sensitive and specific detection systems for gastrointestinal pathogens. In the past year, two different monoclonal-based, enzyme-linked immunosorbent assays have been described that specifically detect pathogenicEntamoeba histolyticain stool. A number of different pretreatment methods have been employed to improve polymerase chain reaction detection of pathogens in stool. Two studies have used immunomagnetic beads(ie, monoclonal antibody-coated) to selectively isolate salmonellae and shigellae followed by detection using polymerase chain reaction-based tests. Spin column chromatography isolation of Norwalk virus allowed for rapid detection of this virus by reverse transcriptase-polymerase chain reaction. A Quiagen procedure improved detection of the toxin A gene target for direct detection ofClostridium difficileby polymerase chain reaction methods. Results of recent evaluations of new commercially available products for detection ofCryptosporidiumspp are evaluated. This report emphasizes tests with improved sensitivity, specificity, and utility in the clinical microbiology laboratory.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

New studies continue to define how colonic absorption and secretion are regulated by intracellular pH, peptides, inflammatory mediators, laxatives, and antidiarrheal agents. Additional work has addressed the influence of aldosterone on electrogenic sodium absorption and has shown the importance of nutritional status in the action of vitamin A on thyroid hormone modulation of aldosterone action. There is further evidence implicating platelet-activating factor as a mediator of intestinal secretion in inflammatory bowel disease and in the mechanism of action of anthraquinone laxatives. The activity of peptide YY, pituitary adenylate cyclase-activating polypeptide, endothelin 1, and guanylin suggest that these peptides may have physiologic or pathophysiologic effects on colonic transport. Studies on methods to enhance the absorption of peptides through the colonic mucosa indicate that it may be possible to improve systemic bioavailability of peptides via this route of administration.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Since the discovery in 1987 that it relaxes vascular smooth muscle, nitric oxide has emerged as an important inhibitory nonadrenergic noncholinergic neurotransmitter throughout the gastrointestinal tract. Immunohistochemical demonstration of its presence and its role in peristalsis, colonic relaxation, and sphincter function are discussed. Intestinal pseudoobstruction poses difficult diagnostic and management problems. However, new primary pathologies causing chronic disease are being identified and pharmacologic treatment of acute disease may be helpful. The repeatability and value of visceral evoked potentials in anorectal disease is discussed. Long-term data about the clinical spectrum of Hirschsprung's disease and immunohistochemical means of diagnosis are reviewed. An update is provided on the etiology and complications of severe constipation. Other areas reviewed include diarrhea and fat excretion, new motility pharmacotherapies, food and colonic motility, and optimum methods for measurement of colonic transit.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Epidemiologic studies have shown that colorectal carcinoma is a disease of Western civilization, most likely related to diet. Diet probably plays a multifactorial role, containing both protective and promoting factors for colorectal carcinoma development. Sorting through the complexities of diet has been a major challenge to epidemiologists. Diets rich in fat and calories seem to contribute to colorectal carcinoma formation, whereas diets rich in plant fiber seem to be protective. Animal studies implicate bile acids, cholesterol, and fatty acids as promoters of colorectal carcinoma, whereas fiber and calcium antagonize cancer promoters. Based on the recent recognition that mutations of specific colon cancer-associated genes correlate with progression of normal mucosa through adenomatous polyps to frank carcinoma, we now approach the question of dietary influences from a new prospective. How do dietary factors affect the mutagenic potential colonic luminal contents? As the links between molecular biology and epidemiology begin to form, new preventative strategies will be developed and tested that may prove to dramatically reduce the incidence of colon carcinoma.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Significant advances were made this past year in our understanding of the molecular genetics and pathogenesis of colorectal cancer. Direct applications of this information are being implemented into clinical practice. Divergent reports over the effectiveness of fecal occult blood testing have failed to clarify screening recommendations. As the emphasis on cost-effective screening for colorectal cancer increases, the future appears to lie in determining individual susceptibility with the use of genetic markers and the adjustment of screening recommendations accordingly.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Literature highlights from the past year pertaining to endoscopy of the colorectum are discussed. As most journal articles have dealt with applications in the screening, diagnosis, and management of colorectal neoplasia, the critique reflects this emphasis. Diagnostic and therapeutic advances, safety and monitoring information, and training issues in colonoscopy are also covered.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The past year's literature is replete with publications discussing a variety of colorectal topics. Many of the particularly useful articles concerning diverticulitis, the ileal pouch-anal anastomosis, laparoscopic colorectal surgery, rectal procidentia, stomas, surgical techniques, large bowel trauma, and assorted miscellaneous conditions are reviewed.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Diarrheal disease has long been recognized as a cause of morbidity and mortality in children in the developing world. Small bowel infections play a major role in this diarrheal disease. With the advent of the AIDS epidemic, diarrheal disease is gaining importance as a syndrome that may severely compromise the quality of life of these patients. In addition, in the past year several dramatic outbreaks of diarrheal disease related to contaminated food or water have occurred. This review examines recent papers that discuss infectious causes of diarrheal disease in AIDS patients, travelers, and individuals who may have been exposed to contaminated food or water, and touches on treatment modalities.

ISSN:0267-1379    

出版商:OVID    

年代:1994

数据来源: OVID