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101.
102.
Bone marrow transplantation attenuates murine IgA nephropathy: role of a stem cell disorder 总被引:4,自引:0,他引:4
Imasawa T Nagasawa R Utsunomiya Y Kawamura T Zhong Y Makita N Muso E Miyawaki S Maruyama N Hosoya T Sakai O Ohno T 《Kidney international》1999,56(5):1809-1817
BACKGROUND: The pathogenesis of IgA nephropathy is still obscure. The aim of this study was to investigate whether the fundamental pathogenesis of IgA nephropathy lies in bone marrow stem cells (BMCs). METHODS: We used donors of two different strains for bone marrow transplantation (BMT) into mice with a high content of serum IgA (ddY strain, HIGA mice), a murine model of IgA nephropathy. One group (B6-->HIGA, N = 5) received BMCs of C57BL/6j (B6) mice, and the other (HIGA-->HIGA, N = 8) were reconstituted with BMCs of HIGA mice. RESULTS: Twenty-six weeks after BMT, in B6-->HIGA mice, mesangial deposits of IgA and C3 were statistically milder than those in HIGA-->HIGA mice. Light microscopic observations disclosed that glomerular sclerosis and mesangial matrix expansion in B6-->HIGA mice were decreased compared with those in HIGA-->HIGA mice. These B6-->HIGA mice also excreted less urinary albumin than HIGA-->HIGA mice. Furthermore, serum levels of IgA in B6-->HIGA mice were markedly lower than those in HIGA-->HIGA mice. Size analysis of serum IgA revealed that macromolecular IgA were notably lower in B6-->HIGA mice than in HIGA-->HIGA mice. CONCLUSIONS: Our results suggest that qualitative and quantitative changes of serum IgA are determined at the level of stem cells, and that BMT from normal donors can attenuate glomerular lesions in HIGA mice. This approach may offer a new avenue to study the pathogenesis of IgA nephropathy. 相似文献
103.
104.
The effect of tulobuterol tape on histamine-induced bronchoconstriction in conscious guinea pigs: long duration of action 总被引:2,自引:0,他引:2
Musoh K Kawamura K Miyake I Shimada S Ohashi T Iwanaga Y Morikawa K Kato H 《Japanese journal of pharmacology》1999,79(3):401-402
The objective of the present study was to determine the action duration of tulobuterol tape within a 24-hr period in conscious guinea pigs. The bronchoconstriction induced by histamine-inhalation was significantly inhibited by tulobuterol tape in comparison with its placebo tape 8 and 12 hr after binding, and the inhibitory rate was 50+/-11% and 35+/-13%, respectively. Twenty-four hours after binding, the inhibitory effect of tulobuterol tape gradually diminished, but the inhibitory rate was maintained at 30+/-14%. These results suggest that tulobuterol tape has a long lasting bronchodilatory action. 相似文献
105.
Akagawa H Takano Y Ishii A Mizuno S Izui R Sameshima T Kawamura N Dobashi K Yoshioka T 《The Journal of antibiotics》1999,52(11):960-970
Stresgenin B was isolated as an inhibitor of heat-induced heat shock protein (HSP) gene expression from a culture broth of Streptomyces sp. AS-9 by silica gel chromatography and HPLC. The molecular formula of the novel compound was determined as C11H13NO5 by high resolution FAB-MS analysis, and the structure was determined by UV, 1H NMR, 13C NMR, HMQC, HMBC, and NOESY spectra. Stresgenin B inhibited heat-induced luciferase reporter-gene expression directed by the human hsp70B promoter in Chinese hamster ovary (CHO) cells at concentrations lower than the concentrations for inhibition of dexamethasone-induced luciferase reporter-gene expression directed by the mouse mammary tumor virus (MMTV)-LTR promoter. The inhibition of heat-induced reporter gene expression was evident even when cells were exposed to stresgenin B only during heat stress treatment. Moreover, the compound inhibited heat-induced syntheses of hsp72/73, hsp90, and hsp110 and thereby suppressed the induction of thermotolerance. Stresgenin B showed moderate cytotoxic activities against several neoplastic cell lines and also showed antibacterial activities against Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus strains. 相似文献
106.
Masaya Kitamura Kiyomi Matsumiya Mikio Namiki Tomoko Hara Tsukasa Seya Akihiko Okuyama 《Journal of assisted reproduction and genetics》1996,13(8):652-656
Purpose: Membrane cofactor protein (MCP), CD46, whose primary function is to protect host cells from homologous complement, has been presumed to serve as a sperm adhesion molecule for oocytes. The purpose of this study was to clarify the relationship between the properties of MCP expressed on epididymal sperm and their fertilizing ability in a recently developed strategy for assisted reproduction.
Methods: We collected ejaculated sperm from normal subjects and epididymal sperm from vasectomized subjects and patients with congenital absence of the vas deferens. Western blotting and cofactor activity assay were performed to investigated the structural and functional properties of MCP.
Results: Epididymal spermatozoa which showed a reduced fertilizing ability tended to react poorly with antibodies against MCP and also showed low cofactor activity, indicating weak complement regulatory activity compared to that of ejaculated spermatozoa.
Conclusions: MCP is sufficiently expressed in ejaculated sperm in men with a normally developed epididymis but is diminished in epididymal sperm from men with congenital or acquired obstruction of the vas deferens. 相似文献
107.
Fujimura T Yonemura Y Kawamura T Nojima N Satoh T Hirono Y Kinami S Fushida S Nishimura G Miwa K Miyazaki I 《Oncology reports》1996,3(3):513-517
Cytoreductive resection (RST), chemohyperthermic peritoneal perfusion (CHPP) and/or intra-aortic chemotherapy (IA-chemo) were performed for peritoneal dissemination in gastric cancer. Ninety-six patients with peritoneal dissemination were grouped into tubercular (TB), 40; nodular (ND), 31; diffuse (DF) type, 19; and others, 6, respectively, by the gross findings. Sixty-three patients underwent RST. Fifty-nine patients received CHPP by 10-liter heated saline. Thirty patients underwent intra-aortic catheterization for the IA-chemo. The 1-year and 2-year survival rate (1-ysr and 2-ysr) of the RST(+) group were 47% and 10% significantly greater than the 9% and 0% of the RST(-) group (p<0.001). The 1-ysr and 2-ysr of the CHPP(+) group were 37% and 11% significantly greater than the 27% and 0% of the CHPP(-) group (p=0.04). In the TB type the 1-ysr and 2-ysr of the former was 43% and 8% significantly greater than the 15% and 0% of the latter (p=0.04). But there was no significant difference in survival time between the CHPP(+) and the CHPP(-) group in the ND type (p=0.22) or in the DF type (p=0.42). The 1-ysr and 2-ysr of the IA-chemo(+) group were 49% and 19% significantly greater than the 27% and 2% of the IA-chemo(-) group (p<0.01). In the DF type the 1-ysr and 2-ysr of the former was 50% and 33% significantly greater than the 8% and 0% of the latter (p=0.02). However, there was no significant difference in survival time between the IA-chemo(+) and the IA-chemo(-) group in the TB type (p=0.06) or in the ND type (p=0.50). Moreover, the effect of the combination therapy of CHPP and IA-chemo (the sandwich therapy, SDW) were examined. The 1-ysr and 2-ysr of the SDW(+) group were 49% and 22% significantly greater than the 24% and 0% of the SDW(-) group (p=0.002). The sandwich therapy should be performed in addition to cytoreductive surgery for improvement of prognosis in the patient with intractable peritoneal dissemination. 相似文献
108.
Tsuyoshi Takada Masaya Kitamura Kiyomi Matsumiya Tsuneharu Miki Hisakazu Kiyohara Mikio Namiki Akihiko Okuyama 《The Journal of urology》1996,156(5):1652-1654
Purpose
We evaluated infrared thermometry for measurement of reflux of blood via the internal spermatic vein.Materials and Methods
The change in scrotal temperature in patients with varicoceles and controls with different positions was measured with an infrared thermometer.Results
Scrotal neck temperature in the patients increased during Valsalva's maneuver with upright position (mean plus or minus standard deviation 34.62 plus/minus 1.20 to 36.05 plus/minus 1.42C), while no statistically significant increase occurred in the controls (32.91 plus/minus 0.92 to 33.42 plus/minus 1.15C). Two weeks after high ligation of the internal spermatic vein the scrotal temperature in the patients decreased to the same level (0.59 plus/minus 0.84C) as in the controls. Using this method 2 subclinical varicoceles were also found on the right side in patients with a left varicocele.Conclusions
Infrared thermometry is noninvasive, rapid and simple for documenting varicoceles, including subclinical disease. 相似文献109.
110.