ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Secretory diarrhea can be elicited by bacterial toxins, hormones, chemical stimulants such as laxatives, and mediators released during mucosal inflammation. These peptide and nonpeptide mediators can have direct and indirect effects as secretagogues by interfering with ion transport through channels and exchangers. Molecular biology techniques have led to the cloning of isoforms of the Na+/H+exchanger, provided further information on regulation by the cystic fibrosis transmembrane conductance regulator of Cl-channels, and identified further characteristics of the P-type ATPase that may play a role in K+absorption by the colon. New studies have shown that HCO-3secretion is stimulated by cyclic AMP and cyclic GMP. Guanylin has been found in intestinal enterochromaffin cells, leading to speculation that it may be released luminally from these cells. Enteric neurons and mediators produced by immunocytes and mast cells are stimulants of secretion in inflammatory bowel disease. In this regard, nitric oxide has variable effects on ion transport, including stimulation secretion by the rat colon and guinea pig small intestine. This free radical seems to be involved in secretion evoked by castor oil and other laxatives. New approaches to pharmacotherapy for secretory diarrhea include studies on the enkephalinase inhibitor acetorphan, loperamide oxide, and use of the synthetic somatostatin analogue octreotide for AIDS-related diarrhea. Glutamine was found more effective than glucose at stimulating Na+absorption by the pig intestine, suggesting that it may be a useful addition to oral rehydration solutions. The new knowledge about mechanisms of anion secretion, mediators of secretion, and molecular mechanisms for inhibition of secretion will undoubtedly contribute to better management of secretory diarrhea due to enteric infection, inflammatory bowel disease, and AIDS.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The major development in the anorectal field over the past year has been the recognition of the high incidence of structural sphincter damage that occurs during childbirth, its characterization using anal endosonography, and the implications for surgical treatment. Fecal incontinence also occurs in patients with progressive systemic sclerosis owing to internal sphincter fibrosis and changes in rectal compliance and prolapse. The clinical efficacy and safety of laxatives and antidiarrheal drugs are reviewed. Recent reviews on biofeedback treatment and observations about altered autonomic function in constipation are covered. Congenital anorectal malformations may be related to sacral spinal cord maldevelopment and are often complicated by long-term bowel dysfunction. Visceral hypersensitivity in functional disorders may be modified by octreotide. Prokinetic erythromycin analogues are beginning to emerge.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The irritable bowel syndrome (IBS) is a heterogeneous symptom complex consisting of altered bowel habits and abdominal pain. Symptoms of IBS are prevalent in the community and IBS represents the most common diagnosis of patients seen by gastroenterologists. The pathophysiology of IBS is poorly understood, but is probably multifactorial with contributions from abnormal gut motility, enhanced visceral perception, and diffuse neural and smooth muscle dysfunction, often in a setting of an abnormal psychiatric profile. The treatment of IBS has centered on the control of dominant symptoms of constipation, diarrhea, or abdominal pain. Recent novel investigations have concentrated on controlling the pain of IBS via inhibitory actions on visceral afferent neural pathways. Although treatment often does not abolish symptoms in IBS, the overall extended outlook for patients with IBS is good, with most patients either experiencing reductions in symptoms or developing the means to cope with them.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Clostridium difficileandEscherichia coliO157:H7 are increasingly recognized causes of bacterial toxin-mediated colitis in immunocompetent individuals. Infection with these organisms results in significant morbidity and sometimes fatal complications. In the immunocompromised patient population, life-threatening and disabling diarrhea results from gastrointestinal infection withCryptosporidium, cytomegalovirus, and numerous mycobacterial species.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The specific etiologies of ulcerative colitis are unknown, but ongoing laboratory and clinical research is leading to holistic concepts of disease pathogenesis. At present, it is hypothesized that immune stimulation by gut lumenal antigens, defects of the gut mucosal barrier, immune regulatory disturbances, generation of pro-inflammatory mediators, and other gut physiologic factors all contribute to the development of idiopathic inflammatory bowel diseases in genetically susceptible individuals. This review presents the past year's progress in investigations on the pathogenesis of and medical-surgical treatment interventions for ulcerative colitis.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Advances in understanding the biology of colorectal cancer and the development of new diagnostic and therapeutic techniques have made the past year an exciting one. Molecular epidemiology has begun to identify specific steps involved in colorectal carcinogenesis; genes responsible for development of hereditary and nonhereditary cancers have been identified and the role of oncogenes in colorectal carcinogenesis is becoming clear. The ability to more precisely stage and localize cancers will allow application of more precise treatment strategies including primary and adjuvant therapy. Also, minimally invasive surgical resection is now being evaluated for treatment of colorectal cancer as the roles of adjuvant chemotherapy and radiation therapy are becoming more sharply defined.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Diverticular disease is a benign condition with potentially lethal complications; an extensive review from the past year literature is discussed. It is our intention to focus on the evaluation and management of the patient with complicated diverticular disease, localized or generalized peritonitis, obstruction, diverticular fistulas, and massive hemorrhage. A good categorization of perforated diverticular disease is presented based on selected articles. We also include advances in antibiotic therapy and the role of radiology, fundamentally, computed tomography in the treatment of pelvic abscess. Finally, an algorithm as a guideline for the treatment of complications in diverticular disease is included.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

The most noteworthy recent developments regarding infections of the intestinal tract have been the emergence of old bacterial foes in new guises. These developments include the identification of a new serotype of toxigenicVibrio choleraewith the potential to cause epidemics, the recognition of novel varieties of diarrheagenic strains ofEscherichia coli, and the emergence ofSalmonellaandShigellaspecies resistant to most clinically useful antibiotics. On the other hand, we are witnessing the onset of a new age of immunization based on genetically engineered vaccines which after a single oral dose will afford long-lived mucosal immunity to infection. These exciting discoveries have been accompanied by an improved understanding of the pathogenesis of bacterial diarrhea and its systemic sequelae. The aim of this review is to highlight some of these developments.

ISSN:0267-1379    

出版商:OVID    

年代:1995

数据来源: OVID