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Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS04 for 48–96 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen.  相似文献   
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118 multibacillary leprosy patients with differential manifestations were studied for the antigens they expressed at MHC loci to investigate the role of human leukocyte antigens in the differential response to the same causative agent. While the lepromatous leprosy (LL) patients showed a significant increase of Bw60, DR2, DRw8 and DQw1, borderline lepromatous (BL) patients had Bw52, DR9 and DQw7 significantly more often as compared to the normal controls. A comparison of LL, BL and mid-borderline (BB) patients showed a significantly higher frequency of Bw60 in LL patients as compared to the BL. However, Bw52, Bw53, DR9 and DQw7 were found significantly more often in the BL patients as compared to the LL patients but the difference failed to reach significance after pc. A comparison of HLA antigens in BB patients with those of either the LL or BL patients did not show any significant differences.  相似文献   
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PurposeNoroviruses are common viral agents in acute diarrhea in all age groups worldwide. Norovirus has been classified into 10 genogroups, GI to GX with over 48 genotypes among them the GII.4 genotype has evolved over time with a clear pattern of periodic variant replacement. Immunity is strain or genotype specific with little or no protection conferred across genogroups. The present study was aimed to determine the epidemiology, prevalent genotypes of norovirus in children below five years of age in the Hyderabad region, India.MethodsThe stool samples and clinical data were collected from 458 children below 5 years of age comprising of cases with acute gastroenteritis (n ?= ?366) and a control group (n ?= ?92) admitted to the pediatric ward. All the samples were tested for Norovirus by ELISA and RT-PCR. Sequencing was done for predominant strains.Results10.3% (n ?= ?38) of cases and 3.2% (n ?= ?3) of the control group were found to be Norovirus positive. Predominant genotypes were GII-82.5% followed by GI-12.5%.ConclusionSequencing and Phylogenetic analyses of 20 GII.4 strains was done. All of the isolates are clustered away from published the GII.4 variants thus suggesting the appearance of a new variant.  相似文献   
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Leprosy patients undergoing phase II trials in two hospitals of New Delhi, India, were HLA typed to see the association of HLA with differential responsiveness toMycobacterium w vaccine. The vaccine comprises an atypical, nonpathogenic mycobacterium,Mycobacterium w, which has cross-reactive antigens withM. leprae. Multibacillary patients who are lepromin negative are vaccinated at an interval of 3 months. Considerable improvement is evident in the patients in terms of a decline in bacterial indices and histopathological and immunological upgrading. But all the patients do not respond to the vaccine in the same manner; some are slow responders, while others are good responders. HLA-A28 and DQw3 (DQw8+9) were found to be associated with slow responsiveness, while DQw1 and DQw7 were found to be associated with a more rapid responsiveness to theM. w vaccine. However, these associations were not significant afterP correction for the number of antigens tested for each locus except for HLA-DQw3 (DQw8 and DQw9) and DQw7. DQw7, a new defined split of HLA-DQw3, seems to be associated with the responsiveness toM. w vaccine.  相似文献   
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Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL) cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as well. Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin, gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation with the ghrelin staining results. All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia, as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such staining was confined to the Sevier-Munger, and VMAT-2 positive cells only. Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL cell proliferations needs to be investigated further.  相似文献   
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A quantitative chemical analysis of total cholesterol, bilirubin, calcium, inorganic phosphate and iron of three types of biliary calculi (cholesterol, pigment and mixed) of 40 gall stone former was carried out and correlated to with those of there sera. A moderately positive correlation for inorganic phosphate, Ca2+ and Fe2+ content of sera and calculi of cholesterol stone patient was found. A Good positive correlation for total cholesterol, a moderately positive correlation for bilirubin and iron but no correlation for inorganic phosphate and calcium content of sera and calculi of pigment stone patient was observed. A good moderately positive correlation for iron but no correlation for total cholesterol, bilirubin, inorganic phosphate and Ca2+ content of sera and calculi of stone patient was found.  相似文献   
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Granulosa Cell Tumors (GCT) constitutes 1.5% to 3.5% of all primary ovarian neoplasms. They may be solid, cystic or both. Unilocular cystic GCT are very rare. We report here a case of 32 years female with unicystic GCT in which the distinction from follicular cyst was difficult and was made by carefully examining the lining of the cyst,which showed occasional multiple layers of granulosa cells with a few Call-Exner bodies.  相似文献   
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