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21.
P. Vento T. Kiviluoto H. J. Järvinen S. Soinila 《Scandinavian journal of gastroenterology》2013,48(2):180-189
Background: Nitric oxide (NO) has an important role both in normal physiology and pathological events of the colon. Our aim was to study possible changes of the three nitric oxide synthases in ulcerative colitis (UC). Methods: Tissue samples from normal colon and least and moderately affected regions of ulcerative colitis colon were obtained at surgery and immunostained for NOS-1, NOS-2, NOS-3, and GAP-43, a marker of nerve fibers. Quantitative analysis of NOS-1 immunoreactivity was performed on the circular muscle layer. Results: NOS-1-immunoreactive fibers in the muscularis mucosae disappeared in least affected and moderately affected UC colon. Quantitative analysis of NOS-1-immunoreactive nerve fibers in the circular muscle showed no differences between normal and diseased colon. NOS-2 immunoreactivity appeared apically in the epithelial cells. In normal colon some specimens showed immunoreactivity in lower parts of crypts. NOS-2 immunoreactivity increased according to the severity of UC. NOS-3 immunoreactivity was exclusively localized in the vascular endothelium. The difference in NOS-3 staining intensity between the lamina propria and submucosa observed in normal tissue disappeared in moderately affected UC colon. The number of NOS-3-immunoreactive vascular profiles increased in the lamina propria of UC colon. Conclusions: All three NOS isoforms show specific changes in UC colon. 相似文献
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B. A. J. Walters R. Stafford R. K. Roberts E. Seneviratne 《Internal medicine journal》1982,12(3):255-258
Abstract: Contamination and crossinfection with Clostridium difficile in an intensive care unit. B.A.J. Walters, R. Stafford, R. K. Roberts and E. Seneviratne, Aust. N.Z. J. Med., 1982, 12, pp. 255–258. An outbreak of pseudomembranous colitis in an intensive care unit is described. This resulted in environmental contamination by Clostridium difficile. The outbreak could be traced to one patient who received several antibiotics over the preceding three months. A search was conducted for asymptomatic carriers among patient and staff but none were found. Aquisition of C. difficile from inanimate environmental sources was the most probable means of transmission of the organism. Its persistence in the hospital environment for several weeks, most likely as spores, suggests that patients who develop pseudomembranous colitis should be isolated, especially in areas of high antibiotic usage. 相似文献
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Minjae Joo Han Sang Kim Tae Hoon Kwon Alisha Palikhe Tin Sandar Zaw Ji Hoon Jeong Uy Dong Sohn 《The Korean journal of physiology & pharmacology》2015,19(1):43-50
It has been shown that the extracts including eupatilin and quercetin-3-β-D-glucuronopyranoside had mucoprotective effects on the esophagus and stomach through their antioxidant activities. This study was designed to investigate the anti-inflammatory effect of these flavonoid compounds in an animal model of inflammatory bowel disease induced by 2,4,6-trinitrobenzene sulfonic acid. Experimental colitis was induced by intracolonic administration of 2,4,6-trinitrobenzene sulfonic acid. Extracts including eupatilin or quercetin-3-β-D-glucuronopyranoside were orally administered to animals 48, 24, and 1 h prior to the induction of colitis and then again 24 h later. The animals were sacrificed 48 h after by 2,4,6-trinitrobenzene sulfonic acid treatment and the macroscopic appearance of the colonic lesions was scored in a blinded manner on a scale of 1 to 10. The inflammatory response to colitis induction was assessed by measuring myeloperoxidase activity, nitric oxide production, tumor necrosis factor-α expression, total glutathione levels, and malondialdehyde concentrations in the colon. The results indicated that extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside dose-dependently improved the morphology of the lesions induced by 2,4,6-trinitrobenzene sulfonic acid and reduced the ulcer index accordingly. In addition, rats receiving extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside showed significantly decreased levels of mucosal myeloperoxidase activity, nitric oxide production, tumor necrosis factor-α expression, and malondialdehyde levels, and increased total glutathione levels. Extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside ameliorated the inflammatory response and colonic injury in acute colitis by decreasing oxidative stress and neutrophil activation. Extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside may inhibit acute colitis. 相似文献
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《Gastroenterologia y hepatologia》2022,45(7):499-506
BackgroundIn the last decade, new therapies with different mechanisms of action have been approved for the treatment of moderate to severe Crohn's disease (CD) and ulcerative colitis (UC). Due to the lack of comparative head-to-head trials, the ideal positioning of agents as the most appropriate first- or second-line therapies remains to be defined.ObjectiveThis survey aimed to evaluate the perception and decisions of Brazilian Inflammatory Bowel Diseases (IBD) specialists in positioning of new therapies (vedolizumab [VEDO], ustekinumab [UST] and tofacitinib [TOFA]) in the management of IBD in different clinical scenarios.MethodologyAn anonymous national web-based questionnaire was used to determine the positioning of treatment options in different clinical scenarios (using Google Forms platform), which involved different age ranges, phenotypes, clinical situations and previous exposure to anti-TNF agents (14 scenarios for CD and 10 scenarios for UC). In CD, physicians could choose between UST or VEDO, whilst in UC, between UST, VEDO or TOFA. Six reasons for the specific choice were proposed, such as mechanism of action, safety, method of administration or onset of action. Statistical analysis was carried out with chi-square and t-tests.ResultsA total of 150 out of 672 GEDIIB IBD specialists (22.32%) responded to the survey. In CD scenarios, UST was the most dominant choice (11/14 scenarios), with VEDO dominating only 3 clinical situations. In UC scenarios, VEDO was the dominant choice (8/10), with UST being chosen for scenarios that included extraintestinal manifestations. Among the reasons for specific choices, the most commonly chosen were the higher efficacy due to the intrinsic mechanism of action and safety profile.ConclusionsUST was the dominant choice as compared to VEDO in CD in most scenarios, especially due to its mechanism of action and safety. VEDO was the dominant choice as compared to UST and TOFA in UC scenarios, mainly for reasons also related to its mechanism of action and safety profile. Comparative studies including patient outcomes are needed to better define the positioning of new IBD therapeutic options in our country. 相似文献
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Dr. G. H. Welch F.R.C.S. M. G. Shearer F.R.C.S. C. W. Imrie F.R.C.S. J. R. Anderson F.R.C.S. D. G. Gilmour M.D. F.R.C.S. 《Diseases of the colon and rectum》1986,29(6):410-412
The involvement of the entire colon in an ischemic process is unusual because of the dual source of blood supply to the large
bowel. Three cases of total ischemic colitis are presented. A precipitating cause to account for the distribution of ischemia
was identified in each patient. 相似文献