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91.
Hayashi M Ueda Y Yamaguchi T Sohma R Shibazaki M Ohkura T Inaba N 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,53(3):113-119
PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients. 相似文献
92.
The Epstein-Barr virus (EBV) has been detected in certain types of lymphoma and some epithelial neoplasms including nasopharyngeal lymphoepithelioma, and rare lymphoepithelioma-like carcinomas occurring in a variety of organs including, most recently, the stomach. The authors investigated the possibility that EBV may be present not only in the rare gastric cancers that resemble nasopharyngeal lymphoepithelioma, but also in typical gastric adenocarcinoma. EBV sequences were detected in 22 of 138 (16%) cases of typical gastric adenocarcinoma by polymerase chain reaction and in situ hybridization (ISH) techniques. The EBV genomes were specifically present within the gastric carcinoma cells in an even distribution. The EBV genomes were also present in adjacent dysplastic epithelium but were absent in surrounding lymphocytes, other normal stromal cells, intestinal metaplasia, and normal gastric mucosa. The EBV genomes in the infected gastric carcinoma cells are expressed as EBV RNA was detected by ISH. EBV was most often detected in gastric tumors from men (21%) compared with women (3%). Thus some cases of gastric adenocarcinoma are EBV-associated. 相似文献
93.
Kondo H Tatsumi N Sakamoto H Fernandes B Modi G Raby A 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(5):480-484
The increasing complexity of diseases and advancing medical technologies have recently raised the number of test items and their use. This has caused each department to ask for clinical support by medical technologists, including consultation services on clinical laboratory tests in Japan. Under these circumstances, we think it is necessary to consider a Japanese education system for medical technologists to foster people with advanced ability capable in providing adequate clinical support. It is important that we study medical technologist systems and education systems superior to than ours. Therefore, to investigate the state of the Japanese education system for medical technologists, we conducted a comparison between the medical technologist systems and education systems in foreign countries and those of Japan. The social background in which medical technologists are positioned, their scope of work, and the education systems overseas are different from Japan on many points and we were given many suggestions for what a system in Japan should be like. 相似文献
94.
The effects of electrical stimulation of ventral subiculum (VSB) of the hippocampus of the thermosensitive neurons in the preoptic area were studied in urethane-anesthetized rats. VSB stimulation affected thermosensitive neurons more frequently (92.1%, 58 of 63) than thermally insensitive neurons (71.4%, 55 of 77). The majority of the VSB-responsive thermosensitive neurons (33 of 44 warm-units and 11 of 14 cold-units) were initially inhibited following stimulation. The result provides further support for the involvement of hippocampus in the central control of thermoregulation. 相似文献
95.
Shimizu C Hasegawa T Tani Y Takahashi F Takeuchi M Watanabe T Ando M Katsumata N Fujiwara Y 《Human pathology》2004,35(12):201-1542
Insulin-like growth factor-1 receptor (IGF-1R) has been implicated in regulation in tumor growth. The results of previous studies performed by radioimmunoassay are conflicting, and the prognostic significance of IGF-1R expression in primary breast cancer is still controversial. IGF-1R expression was evaluated in formalin-fixed, paraffin-embedded tissue of 210 primary breast cancer patients by using anti-IGF-1R antibody. The clinicopathologic variables and 5-year disease-free survival were studied, and their correlations between IGF-1R expressions were investigated. IGF-1R overexpression was observed in 43.8% of tumors. IGF-1R overexpression had no correlation with prognosis or with other clinicopathologic parameters, such as age, tumor size, nodal status, histologic grade, hormone receptor status, and human epidermal growth factor 2 status. Though its prognostic value in breast cancer is limited, immunohistochemical evaluation of IGF-1R by using this monoclonal antibody may be useful in translational research using archived material. 相似文献
96.
Cysteine protease of Porphyromonas gingivalis 381 enhances binding of fimbriae to cultured human fibroblasts and matrix proteins. 总被引:3,自引:1,他引:3
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M Kontani H Ono H Shibata Y Okamura T Tanaka T Fujiwara S Kimura S Hamada 《Infection and immunity》1996,64(3):756-762
It has been shown that Porphyromonas gingivalis 381, a suspected periodontopathogen, possesses fimbriae on its cell surface. The organism is also known to produce proteases which can degrade the host cell surface matrix proteins. In this study, we investigated the effect of protease on the binding of the purified P. gingivalis fimbriae to cultured fibroblasts or matrix proteins. A protease that can hydrolyze benzoyl-L-arginine p-nitroanilide was obtained from P. gingivalis 381 cells by sonication in phosphate-buffered 0.2% Triton X-100 and was purified by column chromatography. The molecular size of the protease was estimated to be 55 kDa by gel filtration or 47 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The enzyme activity was markedly inhibited by sulfhydryl reagents, antipain, and leupeptin. The protease degraded various host proteins, including collagen and fibronectin, and cleaved the COOH terminus of the arginine residue in peptides such as benzoyl-L-arginine p-nitroanilide. However, P. gingivalis fimbriae were not degraded by protease activity. The enzyme activity was enhanced in the presence of reducing agents or CaCl2. When cultured fibroblasts were partially treated with the protease, the binding of the purified P. gingivalis fimbriae to the fibroblast monolayer was increased significantly. However, this enhancing effect was suppressed upon the addition of antipain and leupeptin. Similarly, binding of the fimbriae to the collagen or fibronectin immobilized on the microtiter wells was also enhanced. Addition of these host matrix proteins efficiently inhibited the binding of fimbriae to the fibroblast monolayer. The binding assay of fimbriae using dipeptidyl ligand affinity column chromatography demonstrated a clear interaction between fimbriae and the arginine residue. Taken together, these results indicate that the P. gingivalis protease at least partially degrades the host matrix proteins, which, in turn, may lead to an increased exposure of the cryptic ligands that can result in enhanced fimbria-mediated binding of this organism to periodontal tissues. 相似文献
97.
Variable region sequences of pathogenic anti-mouse red blood cell autoantibodies from autoimmune NZB mice 总被引:4,自引:0,他引:4
L Reininger T Shibata S Ozaki T Shirai J C Jaton S Izui 《European journal of immunology》1990,20(4):771-777
New Zealand Black (NZB) mice spontaneously develop a severe autoimmune hemolytic anemia due to the production of anti-mouse red blood cell (MRBC) autoantibodies. The contribution of variable region genes and somatic mutations in the pathogenicity of anti-MRBC autoantibodies was investigated by mRNA sequencing of eight NZB anti-MRBC monoclonal autoantibodies, among which five are capable of inducing anemia in BALB/c mice. Here we report that at least three VH gene families (J558, J606 and 3609) and five Vchi subgroups (V chi 8, 9, 19, 21 and 28), in combination with several D, JH and Jchi gene segments, encode anti-MRBC autoantibodies. Thus, the NZB anti-MRBC autoantibodies, whether pathogenic or not, are encoded by a large number of immunoglobulin gene elements and by members of known VH and Vchi gene families with preferential usage of VH gene families most distal to the D regions. The presence of several mutations in the JH gene segments of both IgM and IgG anti-MRBC autoantibodies, whether pathogenic or not, strongly suggests that their VH regions may be highly mutated and that the mechanism of somatic diversification might be important in the generation of anti-MRBC autoantibodies. Our results support the idea that anti-MRBC autoimmune responses are likely to be generated by an antigen-driven mechanism. 相似文献
98.
99.
Toshio Nishikawa Takeshi Kasajima Akira Kajita Mitsunori Yamakawa Gengo Mabuchi Hideo Orihata Toshimitsu Shibata Makoto Nakazawa 《Pathology international》1988,38(5):683-691
A case of adrenocortical carcinoma associated with congenital heart defect in a 6-month-old Japanese girl is reported. A fist-sized tumor was incidentally noted in the right hypochondrium upon admission for cardiac surgery. No clinical endocrinopathy was evident in this case. The resected tumor was encapsulated with smooth surface and no invasion to adjacent tissues or organs was observed. Histologically, the tumor was composed of small cells with granular or clear cytoplasm, and occasional giant cells with single or multiple nuclei. By electron microscopy, the tumor cells showed various nuclear contours with distinct nucleoli and had a moderate amount of cytoplasm containing abundant rough endoplasmic reticulum and mitochondria with variable-sized electron-dense granules. Intercellular desmosome-llke junctions were observed in some tumor cells. Immunohistochemlcally, the tumor cells contained granules positive for estriol, progesterone and Cortisol. These morphological findings including electron microscopic features suggested that the tumor cells had a malignant character. 相似文献
100.
Noriyuki Sato Takashi Minase Yutaka Yoshida Eimei Narimatsu Kohzo Muroya Kazuaki Asaishi Kokichi Kikuchi 《Pathology international》1984,34(6):1355-1363
A rare case of extraskeletal mesenchymal chondrosarcoma in a 47-year-old woman is reported. The tumor was located in the soft tissue of left upper arm without any involvement of the humerus. The outer portion of the tumor was histologically composed of primitive mesenchymal cells, and the inner portion showed zones of cartilaginous differentiation. Ultrastructurally, the tumor cells in the primitive areas had a relatively small number of mitochondria, rough endoplasmic reticulum, and free polysomes, and the matrix of the tumor consisted of dense bundles of collagen fibrils. The cartilaginous cells seen in the central portion of tumor were embedded in the matrix of abundant collagen fibrils and matrix granules. They had polysomes, well-developed Golgi complexes, and ample rough endoplasmic reticulum frequently with dilatation. Clear zones adjacent to the cells were seen in the extracellular matrix. With a review of the literature, the histogenesis of this particular tumor is discussed. ACTA PATHOL. JPN. 34: 1355–1363, 1984. 相似文献