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71.
Zeynep H. Coban‐Akdemir Wu‐Lin Charng Mahshid Azamian Ingrid S. Paine Jaya Punetha Christopher M. Grochowski Tomasz Gambin Santiago O. Valdes Bryan Cannon Gladys Zapata Patricia P. Hernandez Shalini Jhangiani Harsha Doddapaneni Jianhong Hu Fatima Boricha Donna M. Muzny Eric Boerwinkle Yaping Yang Richard A. Gibbs Jennifer E. Posey Xander H. T. Wehrens John W. Belmont Jeffrey J. Kim Christina Y. Miyake James R. Lupski Seema R. Lalani 《American journal of medical genetics. Part A》2020,182(6):1387-1399
72.
The plasminogen activation system reduces fibrosis in the lung by a hepatocyte growth factor-dependent mechanism 总被引:12,自引:0,他引:12
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Hattori N Mizuno S Yoshida Y Chin K Mishima M Sisson TH Simon RH Nakamura T Miyake M 《The American journal of pathology》2004,164(3):1091-1098
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis. 相似文献
73.
Polymerase chain reaction (PCR) was applied to identify tissue-embedded ascarid nematode larvae. Two sequences of the internal transcribed spacer (ITS) regions of ribosomal DNA (rDNA), ITS1 and ITS2, of the ascarid parasites were amplified and compared with those of ascarid-nematodes registered in a DNA database (GenBank). The ITS sequences of the PCR products obtained from the ascarid parasite specimen in our laboratory were compatible with those of registered adult Ascaris and Toxocara parasites. PCR amplification of the ITS regions was sensitive enough to detect a single larva of Ascaris suum mixed with porcine liver tissue. Using this method, ascarid larvae embedded in the liver of a naturally infected turkey were identified as Toxocara canis. These results suggest that even a single larva embedded in tissues from patients with larva migrans could be identified by sequencing the ITS regions. 相似文献
74.
Battsetseg B Mamiro K Inoue N Makala L Nagasanw H Iwakura Y Toyoda Y Mikami T Fujisaki K 《Journal of medical entomology》2002,39(1):173-176
To investigate the immunological mechanisms of acquired resistance to tick infestation, interferon gamma (IFN-gamma) deficient mice (IFN-gamma mice) were used to assess interleukin-4 (IL-4) and antibody production levels against tick salivary gland antigen on three successive infestations with Haemoaphysalis longicornis Neumann nymphs. The engorged body weight of the ticks decreased during the second and third infestations. Similar observations were noted in IFN-gamma+/+ mice. However, the engorged body weight of the ticks from IFN-gamma +/+ mice were considerably lower than those from IFN-gamma-/- mice. A marked increase in antibody production during the second and third infestations was observed indicating that IFN-gamma-/- mice could acquire immunological resistance against H. longicornis nymphs. Moreover, IL-4 levels were higher during the first and third infestations but decreased during the second infestation. IL-4 levels were significantly higher in IFN-gamma-/- mice than in IFN-gamma+/+ mice. We have shown here that the statistically significant high IL-4 levels observed in IFN-gamma-/- mice may be a result of type 2 helper cell (Th2) polarization. However, the apparently higher IL-4 levels during the first and third infestations and the notable decline during the second infestation suggest that other cytokines or factors in the host immune system may play a part in regulating IL-4 levels. 相似文献
75.
76.
Development of nested PCR based on the ViaB sequence to detect Salmonella typhi. 总被引:1,自引:3,他引:1
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Y Hashimoto Y Itho Y Fujinaga A Q Khan F Sultana M Miyake K Hirose H Yamamoto T Ezaki 《Journal of clinical microbiology》1995,33(3):775-777
For a rapid diagnosis of typhoid fever, we developed a nested PCR based on the nucleotide sequence encoding the Vi antigen. All Salmonella typhi strains along with a Salmonella paratyphi C strain were PCR positive. This assay was able to detect S. typhi at the single-cell level. 相似文献
77.
Yoichiro Kusunoki Yuko Hirai Tomonori Hayashi Seishi Kyoizumi Keiko Takahashi Yukari Morishita Yoshiaki Kodama Mitoshi Akiyama 《European journal of immunology》1993,23(11):2735-2739
We have previously reported 2 cases of healthy men showing in vivo monoclonal expansion of mature CD4? CD8? αβ T cells. In the present study, an additional 3 adults were found to exhibit such an expansion, among a total 464 adult donors studied. These 5 individuals were otherwise physiologically normal, with no history of severe illness and autoimmune disease at the time of examination. To investigate the mechanisms of the clonal expansion, further characterization of the clonal cells was attempted. No apparent preference for usage of the Tcell receptor β chain variable region was observed in the clonal T cells. These clonal T cells showed lectin-dependent or redirected antibody-dependent cell-mediated cytotoxicities, whereas they could not lyse autologous lymphoblastoid cell lines. Failure of Fas antigen expression was not observed for any of these clones. These results suggest that clonal expansion of CD4? CD8? αβ T cells frequently occurs in the periphery without any T cell abnormalities. 相似文献
78.
Toshiaki Maruyama Ichiro Saito Sachiko Miyake Hiroshi Hashimoto Kazuto Sato Hideo Yagita Ko Okumura Nobuyuki Miyasaka 《European journal of immunology》1993,23(9):2059-2065
Synovial T cells play a crucial role in the pathogenesis of rheumatoid arthritis (RA) synovitis. We have quantitatively analyzed the T cell receptor (TcR) variable (V) region gene repertoire of freshly isolated synovial fluid (SF) T cells, comparing it with that of peripheral blood (PB) T cells in RA. The TcR V gene repertoire of PB and SF T cells in RA and osteoarthritis was heterogeneous. In contrast, Vail in SF was expressed to a greater degree in three of five RA patients, and increased levels of Vp6, 1-3 were found in the SF of four of six RA, compared with paired PB. Of note, Vβ6, 1–3 was universally used in four RA patients with a disease duration of less than 10 years, irrespective of their HLA-DR types. This was in contrast to two other RA patients, suffering for more than 20 years, who showed different Vα and Vβ usages. β-chain sequence analysis in RA patients with a preference for Vβ6, 1–3 has shown that a few clones dominated in SF, whereas polyclonality was observed in PB. These findings suggest oligoclonal expansion of T cells in response to specific antigen(s) in the SF of these patients with RA of relatively short duration. Concomitant use of two hydrophobic amino acids, leucine and valine, in the Dβ region was noticeable among the predominant SF clones. These two amino acids might directly contact a peptide specific for the induction of synovitis in RA patients. TcR-directed therapy may, therefore, be useful for the treatment of early RA synovitis. 相似文献
79.
Haruhiko Yoshida Tokichi Yumoto Yoichiro Hamada Toshiyuki Aki Kazuhito Nakai Juichi Ueki 《Pathology international》1989,39(1):55-66
Ffteen cases of peripheral T cell lymphoma were studied to evaluate the respective properties of various histologic types using enzyme histochemical and ultrastructural examinations in addition to immunological methods. Eleven cases in an ATLA negative group manifested various histologic patterns such as IBL like, pleomorphic and Lennert's lymphomas in comparison with the relatively monomorphic proliferation of neoplastic lymphoid cells in the 4 ATLA positive cases. The presence of neoplastic clear cells is characteristic of peripheral T-cell malignancies, and is likely to be found in CD4 lymphomas. There is an occasional reaction of epithelioid histiocytes and plasma cells with eosinophils, the former being designated Lennert's lymphoma and the latter IBL like T-cell lymphoma. Immunological examination revealed four immunophenotypic patterns: (1) CD2+ 3+ 4+ 8+ , (2) CD2+ 3− 4+ 8− , (3) CD2+ 3+ 4− 8+ , and (4) CD2+ 3+ 4+ 8+ , but did not provide information concerning the intimate relationship between histologic types and immuno phenotyes. β-Glucuronidase reactivity, however, contributed to the distinction between helper and suppressor T cell malignancies, suggesting its usefulness for distinguishing these two cell types and their malignant counterparts. 相似文献
80.
An unusual case of a 37-year-old female with xanthomatous bone tumor of the right molar area of the mandible was presented. The tumor was asymptomatic and found to be a well-demarcated intraosseous radiolucent lesion on radiographic examination. Histologically the tumor consisted of two cell types, fibroblastic and xanthomatous cells. There was no osteoid, bone or cartilage formation. However, numerous psammomatous calcified bodies were seen in the fibrous area. Ultrastructural study showed fibroblastic cells in different stages of proliferation as the basis of the tumor which transform itself into xanthomatous cells. From the clinicopathologic findings, our case was thought to be a xanthic variant of non-ossifying fibroma (so-called xanthofibroma) of the mandible. 相似文献