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PURPOSE: Only five percent of all patients with ulcerative colitis develop primary sclerosing cholangitis. T cells accumulate at the sites of the colonic and bile duct inflammation in both ulcerative colitis and primary sclerosing cholangitis. T helper cell populations comprise functionally distinct subsets characterized by the cytokines they produce. Several alterations in cytokine production have been described in patients with ulcerative colitis. The aim of this study was to investigate possible differences in T helper subsets and cytokine production in peripheral blood and colonic mucosa among ulcerative colitis patients with and without primary sclerosing cholangitis. METHODS: Eleven patients with primary sclerosing cholangitis and extensive ulcerative colitis, 11 patients with extensive ulcerative colitis and no liver disease, and 5 patients without any history of liver disease who underwent routine colonoscopy because of previous polypectomy were included in the study. Colonoscopy with multiple biopsies was performed on all patients. Lamina propria mononuclear cells and peripheral blood mononuclear cells were isolated. A modified version of solid-phase enzyme-linked immunospot assay was used for the separate counting of cells producing interferon-gamma, interleukin-2 (T helper 1), and interleukin-4 (T helper 2). RESULTS: No differences in spontaneous production of cytokines from peripheral blood mononuclear cells was found among the three groups. Patients with primary sclerosing cholangitis compared with patients with ulcerative colitis without liver disease showed a significant increase in the number of cells secreting interferon-gamma after purified protein derivative stimulation (P < 0.02). More cells secreting interferon-gamma were found in the two ulcerative colitis groups than in the cell populations from healthy controls (P < 0.03). The number of cells secreting interferon-gamma in the primary sclerosing cholangitis group was significantly lower than in the ulcerative colitis group without liver disease (P < 0.04). The number of cells secreting interleukin-4 was lower in the primary sclerosing cholangitis group than among the patients with ulcerative colitis only (P = 0.05). CONCLUSION: Isolated lymphocytes from colonic mucosa differ in cytokine production in patients with ulcerative colitis with and without primary sclerosing cholangitis.  相似文献   
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We report the case of a 33-year-old man with a severe Crohn's disease since the age of sixteen. He presented with acne and palmoplantar pustulosis associated with a right knee synovitis. Investigations revealed a major axial bone condensation. The association synovitis-acne-pustulosis-hyperostosis-osteitis leaded to the diagnosis of SAPHO syndrome associated with Crohn's disease.  相似文献   
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The molecular dimensions of the potent chemical carcinogen dibenzo[def,p]chrysene, also known as dibenzo[a,l]pyrene, have been determined by X-ray diffraction methods. This analysis shows that the molecule is considerably distorted so that it is non-planar with an angle of 27.6 degrees between the outermost rings and a widening of C-C-C bond angles in the fjord region. The dimensions of the molecular distortion due to atomic overcrowding in the fjord region are presented. This polycyclic aromatic hydrocarbon is a more potent carcinogen than is benzo[a]pyrene or its 11-methyl derivative. Comparisons of the distortions in dibenzo[a,l]pyrene with the geometries of various other polycyclic aromatic hydrocarbons containing fjord- or bay-region methyl groups provide structural data on the ratio of angular to torsional distortion in such overcrowded molecules.  相似文献   
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A nuoG mutation in NADH dehydrogenase I was introduced into a virulent strain of Salmonella serotype Gallinarum, the causative agent of fowl typhoid, using gene replacement with a nuoG open reading frame inactivated by insertion of DNA encoding a kanamycin resistance determinant. The S. Gallinarum nuoG mutant, named SG9NGK, was highly attenuated in chickens. SG9NGK colonized the caeca of chickens less efficiently than the S. Gallinarum parental strain, was less invasive and showed no evidence of multiplication in the liver or spleen. Using a single oral immunization with live bacteria SG9NGK reduced mortality in 2-week-old chickens following challenge with virulent S. Gallinarum from 75% to less than 8%.  相似文献   
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