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991.
Although abnormalities of the male external genitalia (MEG) are a relatively common problem, little is known concerning the molecular mechanisms that finely regulate penile development. We report here the expression of the oxytocin receptor (OTR) gene by real-time RT-PCR in human fetal tissues (11th-12th week of gestation), including the MEG. The developing penis expressed a very high level of OTR mRNA, only a half log(10) unit lower than fetal central nervous system, used as a positive control. The OTR protein is also highly expressed (western, immunohistochemistry and binding studies) and immunolocalized both in the mesenchymal body and in the surrounding blood capillaries, which will later constitute penile trabeculae and sinusoids. Binding studies using [125I]oxytocin antagonist ([125I]OTA) in cultured human fetal penile smooth muscle cells (hfPSMC) revealed the presence of specific OTR with a high capacity and affinity for oxytocin (OT) and for OTA. Increasing concentrations of OT dose-dependently induced intracellular Ca2+ mobilization. Furthermore, OTR mediated an increase in the proliferation and the migration of hfPSMC. In conclusion, we demonstrate that in the developing human MEG, OTR is highly expressed and might be involved in coordinating timely and appropriate proliferation and migration of the penile cells. Thus, OTR might represent an additional target for investigating human fetal MEG organogenesis.  相似文献   
992.
Although malignant fibrous histiocytoma (MFH) is one of the most common soft tissue sarcomas, its pathogenesis remains unclear. In this study, a cell line derived from human MFH, TNMY1, was established from a metastatic chest-wall lesion of a 60-year-old woman with MFH. The TNMY1 cell line was passaged 95 times, and it still retained the biological characteristics of the original tumor. TNMY1 consists of spindle-shaped cells and pleomorphic cells associated with multinucleated giant cells. Immunohistochemical studies showed that the spindle-shaped and pleomorphic cells were positive for vimentin, CD68 and alpha-smooth muscle actin, but negative for epithelial membrane antigen, desmin, muscle actin, alpha-sarcomeric actin, myoglobin, lysozyme and S-100 protein. The cells expressed collagen types I, III and V. These results indicate that MFH may originate from mesenchymal stem cells with the potential to differentiate into either fibroblasts or histiocytes. An elevated level of collagen type V mRNA expression is considered to support a diagnosis of MFH.  相似文献   
993.
Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against -amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthdayPresented in part at the Second International Symposium on the Classification of Pancreatitis, Marseille, 1984, and at the Meeting of the European Pancreatic Club, Manchester, 1985  相似文献   
994.
Lymphocyte subpopulations (B cells, CD4, CD8), interleukin-20 receptors (IL-2), monocytes/macrophages (Leu M5), and HLA-DR antigen expression were studied immunohistochemically on frozen sections from 38 bladder cancer specimens. T cells predominated over B cells in all tumours. CD4-positive lymphocytes predominated over CD8 in the stroma (CD4/CD8: 1·35/1), while in epithelial tumour cells CD8 was the prominent subpopulation (CD8/CD4: 1·75/1). Aberrant HLA-DR expression was found in 21·05 per cent of bladder tumours. A strong correlation between CD4 and CD8 population densities and macrophages with the other subpopulations was noticed. In HLA-DR-positive tumours, there was no correlation of the percentage of positive cells with CD4- and CD8-positive lymphocyte populations. Various parameters including IL-2 receptors, B cells, CD8- and CD4-positive cells, and macrophages did not differ significantly between the groups of tumours expressing and not expressing HLA-DR antigen. There were no statistically significant differences in the population densities of B cells, CD8- or CD4-positive cells, IL-2 receptor, monocytes/macrophages, and HLA-DR antigen expression among various clinicopathological parameters, including growth pattern, histological grade and clinical stage or patient's age and sex. These findings suggest that in transitional cell carcinoma of the urinary bladder, HLA-DR antigen expression is independent of lymphocyte subpopulations. It is therefore possible that HLA-DR expression by tumour cells reflect the existence of separate HLA-DR-positive or HLA-DR-negative tumour clones.  相似文献   
995.
The last decade has witnessed increasing application of human cytogenetic technology to prenatal chromosome analysis. However, unlike the rather uniform peripheral blood T-lymphocyte system which has provided most of our experience in human cytogenetics, long-term amniotic-fluid cell cultures display extreme cellular heterogeneity and disproportionate growth of certain cell types as a consequence of clonal amplification. When they enter cell culture, many of these cells are approching the terminal stages of their respective life spans and may have accumulated chromosomal aberrations. Concern about the possibility of true fetal mosaicism seems warranted chiefly in situations were multiple colonies display potentially viable aberrations. Clonal analysis, preferable of multiple clonal types, and attention to details of clonal morphology are likely to minimize diagnostic errors and undue apprehension resulting from mosaicism in amniotic-fluid cell cultures.  相似文献   
996.
Summary The lamellar cells of the sensory corpuscles of the pig dermis must be considered to be epithelial cells as they contain cytokeratins. The cytokeratins detected are similar to those found in simple epithelia. Moreover, lamellar cells are embedded in an extracellular matrix reminiscent of the basement membrane of epithelium since it contains laminin and collagen IV. The perineural cells surrounding the nerves of pig dermis present the same features.These results suggest that lamellar cells and perineural cells have the same origin. The nature of the lamellar and perineural cells of the rabbit or human dermis is not as clear since cytokeratins were not detected in those cells. These results, together with recent observations on Merkel cells, may indicate that epithelio-neuronal junctions are a general feature of cutaneous sensory receptors.  相似文献   
997.
A subcellular fraction enriched in erythrocyte membranes has been isolated from rhesus monkey erythrocytes infected with Plasmodium knowlesi. Infected cells were lysed by centrifugation through a zone of hypotonic buffer and membranes isolated by equilibrium density gradient centrifugation in the same tube. The purified membrane fraction was shown to include the erythrocyte surface membrane by several methods: electron microscopy, identification of Coomassie Blue stained erythrocyte membrane proteins, identification of band 3 with a monoclonal antibody, and identification of radioiodinated cell surface proteins. The resulting ghosts were shown to be specifically reactive with monkey sera against the variant surface antigens of P. knowlesi by indirect immunofluorescence and membrane agglutination. No reactivity was seen with a monoclonal antibody (13C11) against the intracellular schizont surface. A number of metabolically labelled parasite proteins were enriched in this membrane function, including peptides of 277, 208, 173, 153, 134, 109, 80, 60 and 48 kDa and the variant surface antigens of variable molecular mass (180-207 kDa). These proteins were distinct from the major parasite proteins of total infected erythrocytes and isolated merozoites. The major glucosamine labelled glycoprotein of the internal schizont (230 kDa) was not found in this fraction. Moreover, no fragment of this parasite glycoprotein was found in this membrane fraction, indicating that no part of this molecule is transported to the erythrocyte surface. In contrast, the variant antigen of P. knowlesi, known to be on the erythrocyte surface, could be readily identified as peptides unique to specific cloned parasite lines. We propose that the other nine parasite proteins found within this membrane fraction represent a starting point for the identification of other parasite proteins transported to the surface membrane of the infected erythrocyte.  相似文献   
998.
ABSTRACT: Leukocyte adherence inhibition (LAI) assay was used to evaluate cell-mediated immunity in patients with invasive squamous cell carcinoma of the cervix. The reactivity of the peripheral blood leukocytes of these patients was evaluated after incubation with pooled extracts of allogeneic squamous cell carcinoma of the cervix. One hundred sixty-seven sets of LAI assays were performed on 54 individuals, including 23 patients with Stage I squamous cell carcinoma of the cervix, 9 patients with other stages of this tumor, 9 patients with unrelated tumors and 13 normal healthy volunteers. A protein concentration of one milligram per milliliter in the tumor extract and 10% fetal bovine serum in the feeding media gave the best results. Eighty-seven percent (28/32) of patients with squamous cell carcinoma of the cervix showed marked specific reactivity. No difference was found in the LAI indices of different stages of the disease.  相似文献   
999.
The character of interaction between different strains ofEscherichia coli serotype O26 and cells of continuous cultures of human strains HeLa, Tg-33, and RH was studied in vitro. The phenomenon of cytopathogenic action (CPA) of uropathogenic strains ofE. coli containing heterogenetic type O(H) and B antigens on human cell strains with the corresponding isoantigens was detected after interaction for 6 h. The number of dead cells in these cultures was 1.5–3 times greater than their number in control cultures to whichE. coli cells not containing heterogenetic antigens or containing dissimilar heterogenetic antigens of the human AB0 type were added. It is postulated that this phenomenon plays an important role in the development of chronic forms of colibacillary pyelonephritis.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 5, pp. 568–570, May, 1976.  相似文献   
1000.
音猬因子的功能受体斑片在培养神经干细胞中的表达   总被引:1,自引:0,他引:1  
许汉鹏  胡沛臻  苟琳  张萍  鞠躬 《解剖学报》2002,33(6):561-565
目的 观察在培养的神经干细胞内是否有发育调控分子———音猬因子 (sonichedgehog)功能受体———斑片 (patched)表达。 方法 神经干细胞克隆在体外培养传代后 ,用patched的特异性引物对培养的神经干细胞进行RT PCR分析 ,PCR产物经克隆测序后 ,用地高辛标记克隆的探针 ,对神经干细胞进行原位杂交分析。 结果 神经干细胞克隆内大量的细胞均可表达sonichedgehog的功能受体patched ,patched阳性细胞间未见明显差别 ,克隆边缘与中央的patched分布也未见明显差别。 结论 sonichedgehog信号传导路可能在神经干细胞的增殖与分化过程中起重要作用。  相似文献   
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