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Lipoglycans from mycoplasmas possess the ability to induce the elaboration of procoagulant activity. This represents a third endotoxic property for these polymers, in addition to the pyrogenicity and clotting of Limulus lysate reported previously. Lipoglycans from three species of Acholeplasma (A. axanthum, A. granularum, and A. oculi) stimulated the elaboration in vitro of procoagulant activity by human mononuclear cells to differing extents. Two serotypes, 3 and 4, of Ureaplasma urealyticum also exhibited this stimulatory activity. The activities of lipoglycans tested were, in decreasing order, A. oculi greater than U. urealyticum type 4 greater than A. axanthum greater than U. urealyticum type 3 greater than A. granularum.  相似文献   
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Intra-articular Chlamydial Antigen and Inflammatory Arthritis   总被引:1,自引:0,他引:1  
Joint material from 133 patients with well-characterized inflammatoryarthritis, including individuals likely to have suffered reactivearthiritis, was studied. The majority of patients were alsoexamined for the presence of genital tract infection with Chlamydiatrachomatis. Fluorescein-conjugated monoclonal antibodies demonstratedthe presence of C. trachomatis antigen in synovial fluid celldeposits or synovial sections from inflamed knee joints of sevenpatients with reactive arthritis. The significance of thesefindings is discussed, as is the low rate of detection of chlamydialantigen in either the genital tract or the joint from patientsin this study. We emphasize the need for further work aimedat identifying the relevant immunogenic chlamydial antigensresponsible for the initiation of reactive arthritis.  相似文献   
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AIM: Biopsies of the gastric antrum were reviewed over a period of 10 years to determine the prevalence of Helicobacter heilmannii in symptomatic subjects from this geographical area and to relate its presence to distinctive histopathological and immunohistochemical features. METHODS: Biopsies from 7926 symptomatic patients were reviewed. Ten serial sections were stained with haematoxylin and eosin for conventional histology. Another 10 sections were stained with the Gram method for spiral bacteria. When H heilmannii was suspected, 10 additional serial sections were stained with methylene blue to obtain homogeneous colouring. An equal number of sections from patients affected by isolated H heilmannii or H pylori gastritis were analysed by immunohistochemistry to evaluate lymphoid aggregate/mucosal lymphocyte clonality (CD20 and CD3) and tumour necrosis factor alpha (TNF-alpha) in stromal cells. RESULTS: The prevalence of H heilmannii was 0.1% (eight of 7926), whereas H pylori was present in 60.7% of patients (4813 of 7926). In two of the eight H heilmannii positive patients both helicobacters were found. In all subjects infected by H heilmannii only, distinctive histology (lymphocyte exudation into gastric foveolae) was seen. Lymphoid aggregates, chronic mucosal inflammation with patchy activity, and the absence of epithelial mucus depletion were regular features of H heilmannii gastritis. Immunohistochemistry did not reveal different lymphocyte clonal patterns between H pylori and H heilmannii gastritis: CD20 positive cells were predominant in the centre of aggregates and mucosal infiltrates, whereas CD3 positive cells were prevalent at the periphery of follicles. Only H pylori gastritis showed a significant increase in TNF-alpha positive stromal cells. CONCLUSION: These data suggest that an unusual lymphocyte reaction, with the tendency to invade the foveolar lumen, is a distinctive histopathological aspect of H heilmannii chronic gastritis, although further studies in a larger series are necessary to confirm this fact. Nevertheless, lymphocyte clones do not differ qualitatively from those found in H pylori infection. Moreover, compared with H heilmannii, H pylori provokes a more intense release of TNF-alpha, suggesting that different inflammatory responses exist to these two organisms.  相似文献   
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A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
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Lakhal B, Braham R, Berguigua R, Bouali N, Zaouali M, Chaieb M, Veitia RA, Saad A, Elghezal H. Cytogenetic analyses of premature ovarian failure using karyotyping and interphase fluorescence in situ hybridization (FISH) in a group of 1000 patients. To evaluate the implication of chromosome abnormalities in the etiology of premature ovarian failure (POF), 1000 patients with POF recruited at the Department of Cytogenetics of Farhat Hached Hospital (Sousse, Tunisia) between January 1996 and December 2008. Chromosome analyses were performed by using karyotyping and interphase fluorescent in situ hybridisation (FISH) using a centromeric probe of the chromosome X to look for low‐level mosaicism of X‐chromosome monosomy. Hundred and eight chromosomal abnormalities (10.8%) were found using karyotype analysis. Anomalies were detected in 61 cases out of 432 primary amenorrhea patients (14.12%) and 47 cases out of 568 secondary amenorrhea patients (8.27%). In 23 POF patients among 200 (11.5%) with 46,XX normal karyotype and explored using interphase FISH analysis, the percentage of cells with X‐chromosome monosomy was significantly higher as compared with controls in the same age. The cytogenetic study of POF patients showed a high prevalence of chromosome anomalies either in primary or in secondary amenorrhoea. Mosaic X‐chromosome s aneuploïdy was the most frequent abnormality and some patients with POF may be attributable to low‐level 45,X/46,XX mosaicism detectable using FISH analysis.  相似文献   
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