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31.
E Tanaka K Kiyosawa T Sodeyama Y Nakano K Yoshizawa T Hayata S Shimizu Y Nakatsuji Y Koike S Furuta 《Journal of medical virology》1991,33(2):117-122
In a retrospective study, antibody to hepatitis C virus (anti-HCV antibody) was measured in 80 patients with acute viral hepatitis (type A, 18; type B, 21; type non-A,non-B, 41). Anti-HCV antibody was found in 12 of 20 patients (60%) with non-A,non-B post-transfusion hepatitis (NANB-PTH) and in 9 of 21 patients (43%) with sporadic NANB hepatitis (NANB-SPO). Patients with acute hepatitis type A or type B did not have anti-HCV antibody. The number of patients who developed chronic hepatitis was greater in the group with anti-HCV antibody than in the anti-HCV negative group in both NANB-PTH and NANB-SPO. The difference was significant in those with NANB-PTH (P less than 0.05). To investigate the relationship between the long-term prognosis of NANB-PTH and the course of anti-HCV, we studied anti-HCV antibody in 12 patients who developed chronic type C hepatitis (C-CH) after PTH and followed them for more than 5 years after the development of PTH. One year after the development of PTH, all 12 had anti-HCV antibody. Five lost anti-HCV antibody (group 1) while 7 remained positive (group 2) at the final examination. Four of the 5 patients in group 1 had normal serum transaminases; however, abnormal transaminase persisted in all 7 patients in group 2 until the end of follow-up (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
33.
The corrosion resistance of pure titanium in organic acids 总被引:4,自引:0,他引:4
The purpose of this study was to assess the corrosive properties of titanium at various pH values. Cast pure titanium specimens were immersed in 128 mmol/l of lactic and formic acids at pH 1.0-8.5 for 3 weeks at 37 degrees C. The solubility, color, weight and chemical binding state of specimens were observed. Titanium dissolved in all lactic acid. The amount of dissolved titanium tended to decrease with a higher pH. In formic acid, the amount of dissolved titanium at pH 1.0 was larger than that in lactic acid at the same pH, but less than the detectable limit at pH 4.0 or higher. Significant discoloration was macroscopically observed only in formic acid at pH 2.5 and 4.0. The weight of the titanium samples immersed in lactic acid all decreased, but it was not affected by pH. In formic acid, the weight decreased at pH 1.0 and increased at pH 2.5-5.5. Thickening of the TiO2 corresponding to that showing discoloration was observed in the superficial oxide film of the titanium samples. Our results show that the corrosive properties of titanium are markedly dependent on pH in formic acid, and relatively less dependent on pH in lactic acid in which titanium is dissolvable at pH 1.0-8.5. 相似文献
34.
Takahashi R Akiba K Koike M Noguchi T Ezure Y 《Journal of chromatography. B, Biomedical sciences and applications》2000,742(1):71-78
A new affinity chromatography (hydrophobic-mediated affinity chromatography), which was characterized by the matrix having both affinity site to urokinase and hydrophobic site, was established for the purification of urokinase from human urine. The hydrophobic affinity matrix (tentatively named PAS in the text) was prepared by immobilizing 6-aminocaproic acid on Sepharose CL-6B, followed by a coupling p-aminobenzamidine to a part of the hydrophobic site on the matrix. The PAS matrix was applied to the purification of urokinase from human urine, and high- and low-molecular weight pure urokinases were efficiently obtained in high yield by the present method. 相似文献
35.
Transgenic rabbits with increased VEGF expression develop hemangiomas in the liver: a new model for Kasabach-Merritt syndrome 总被引:5,自引:0,他引:5
Kitajima S Liu E Morimoto M Koike T Yu Y Watanabe T Imagawa S Fan J 《Laboratory investigation; a journal of technical methods and pathology》2005,85(12):1517-1527
Clinical studies have provided ample evidence that high (either systemic or local) levels of vascular endothelial growth factor (VEGF) are associated with several pathophysiological disorders, including hemangiomas. To investigate whether elevated VEGF expression could directly affect these disorders, we created a transgenic (Tg) rabbit model with increased hepatic expression of the human VEGF(165) transgene under the control of the human alpha-antitrypsin promoter. Tg rabbits exhibited marked hepatomegaly, with livers 2.5-fold heavier than those of control rabbits. Histological analysis revealed that the livers of Tg rabbits showed prominent dilation of the sinusoids and formed various-sized blood vessel networks, a feature of diffuse hemangiomas. Immunohistochemical staining revealed that the hepatocytes produced VEGF(165), whereas plasma VEGF(165) was not detected. Furthermore, Tg rabbits suffered from hemolytic anemia, thrombocytopenia and splenomegaly, which was associated with marked extramedullary hematopoiesis. The manifestations of Tg rabbits mimic many of the features of hemangiomatous disorders in humans such as the Kasabach-Merritt syndrome, and therefore this model may be potentially useful for the study of the pathogenesis and complications of hemangiomas as well as the investigation of angiogenesis inhibitors. 相似文献
36.
Ohsawa Y Zhang G Kametaka S Shibata M Koike M Waguri S Uchiyama Y 《Archives of histology and cytology》2003,66(4):367-381
A 35 kD protein was isolated and purified from conditioned media of Bcl-2 cDNA-transfected PC12 cells and its cDNA cloned. A database analysis showed that the 35 kD protein is a rat homologue of the human FLRG protein. The biochemical as well as morphological properties of the rat FLRG protein in PC12 cells were examined and its distribution in rat tissues determined. The levels of FLRG mRNA expressed were low during the fetal period, compared with those of follistatin mRNA. The distribution of FLRG and follistatin mRNAs differed from each other after birth; the expression levels of FLRG mRNA were abundant in the adrenal gland and testis, whereas those of follistatin mRNA and activin A were markedly high in the ovary. The presence of FLRG mRNA and/or protein was confirmed in spermatocytes at various differentiating stages andin endocrine cells of both the adrenal cortex and medulla. When overexpressed in PC12 cells, the FLRG protein was found to be stored in secretory granules of the cells and largely secreted by a regulated pathway, while activin A enhancedthe constitutive secretion of the FLRG protein from wild-typpe PC12 cells, indicating that the FLRG protein possesses dualproperties in secretory pathways. The different distribution between FLRG and follistatin mRNA suggests that, like follistatin in the ovary, the FLRG protein may be involved in the maintenance of spermatogenesis in the testis and the growth and function of adrenal tissue cells, probably by regulating the functions of its binding partners such as the TGF-beta ( superfamily members. 相似文献
37.
Furuta M Kose S Koike M Shimi T Hiraoka Y Yoneda Y Haraguchi T Imamoto N 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(5):429-441
Heat-shock induces a strong stress response and modifies all aspects of cellular physiology, which involves dynamic changes in the nucleocytoplasmic distributions of a variety of proteins. Many distinct nucleocytoplasmic transport pathways exist in eukaryotic cells, but how a particular transport pathway is regulated under different cellular conditions remains elusive. The finding of this study indicate that conventional nuclear import, which is mediated by importin alpha/beta, is down-regulated, while the nuclear import of 70 kD heat-shock cognate protein is up-regulated in heat-shock cells. Among the factors involved in the mediation of the conventional nuclear import, significant levels of importin alpha accumulate in the nucleus in response to heat-shock. An analysis of the behaviour of importin alpha with fluorescence recovery after photobleaching and fluorescence loss in photobleaching studies show that nuclear importin alpha becomes less mobile and its nucleocytoplasmic recycling is impaired in heat-shock cells. These data coincided well with biochemical and cytological studies. Our present data show that heat-shock induces the nuclear accumulation, nuclear retention, and recycling inhibition of importin alpha, resulting in the suppression of conventional nuclear import. This suggests a new regulatory mechanism for the adaptation of cells to environmental changes, such as heat-shock. 相似文献
38.
Imai T Tanaka Y Okamoto T Yamamoto Y Horinouchi T Tanaka H Koike K Shigenobu K 《Acta physiologica Scandinavica》2002,176(1):57-63
Urinary bladder smooth muscle (UBSM) exhibits spontaneous contraction. This spontaneous mechanical activity is myogenic and can be closely related to the UBSM cell action potential to facilitate Ca2+ influx through voltage-gated Ca2+ channels. In the present study, to know whether this membrane electrical event is the exclusive mechanism to trigger spontaneous smooth muscle contraction, we compared the inhibitory effects of Ca2+ channel blockers on the spontaneous action potential and mechanical activity in the isolated guinea-pig UBSM. Both action potential and rhythmic contraction were generated spontaneously in the presence of atropine (1 microM), phentolamine (1 microM), propranolol (1 microM), suramin (10 microM) and tetrodotoxin (1 microM), which suggest that both phenomena were myogenic in origin. Nisoldipine (100 nM) and diltiazem (10 microM) completely eliminated the generation of action potential whereas its frequency was dramatically increased by a dihydropyridine Ca2+ agonist, BayK 8644 (1 microM). In contrast to disappearance of action potential in the presence of Ca2+ channel blockers, spontaneous contraction of UBSM was inhibited only partly by nisoldipine or diltiazem and most of the mechanical components persisted in these channel blockers. These results indicate that spontaneous action potential in UBSM cell is generated through the activation of L-type voltage-gated Ca2+ channels. The subsequent elevation of intracellular Ca2+ concentrations during a burst of action potentials can be partly responsible for the induction of UBSM mechanical activity. In addition, the present study provides evidence that UBSM spontaneous mechanical activity is also attributable to the mechanism(s) other than the generation of Ca2+ spike. 相似文献
39.
J. -M. Chong Y. Shiozawa Y. Hayashi N. Funata T. Takizawa M. Koike M. Fukayama 《Virchows Archiv : an international journal of pathology》1996,428(4-5):261-266
We report a case of pancreatic acinar cell carcinoma which contained a large number of pleomorphic inclusions with fibrillary internal structures and mature zymogen granules. To clarify the significance of fibrillary inclusions in the differentiation of acinar cells of the pancreas, we further investigated fetal pancreases (gestational weeks 16, 17, 19, 20 and 28). We found two types of inclusions: type A, corresponding to fibrillary inclusion of neoplastic acinar cells, was observed only in a 19-week fetus; type B showed a homogeneous density similar to that of zymogen granules. Type B was observed in all the fetuses after the 17th gestational week. Although the type A inclusion might be generated throught a different mechanism than the type B inclusion, the appearance of a large number of fibrillary inclusions in neoplastic acinar cells may represent a transient form of zymogen granule. 相似文献
40.
Li N Nakamura K Jiang Y Tsurui H Matsuoka S Abe M Ohtsuji M Nishimura H Kato K Kawai T Atsumi T Koike T Shirai T Ueno H Hirose S 《Human molecular genetics》2004,13(2):171-179
Systemic lupus erythematosus (SLE), a complex multigenic disease, is a typical antibody-mediated autoimmune disease characterized by production of autoantibodies against a variety of autoantigens and immune complex-type tissue inflammation, most prominently in the kidney. Evidence suggests that genetic factors predisposing to aberrant proliferation/maturation of self-reactive B cells initiate and propagate the disease. In SLE-prone New Zealand Black (NZB) mice and their F1 cross with New Zealand White (NZW) mice, B cell abnormalities can be ascribed mainly to self-reactive CD5+ B1 cells. Our genome-wide scans to search for susceptibility genes for aberrant activation of B1 cells in these mice showed evidence that the gene, Ltk, encoding leukocyte tyrosine kinase (LTK), is a possible candidate. LTK is a receptor-type protein tyrosine kinase, belonging to the insulin receptor superfamily, and is mainly expressed in B lymphocyte precursors and neuronal tissues. Sequence and functional analyses of the gene revealed that NZB has a gain-of-function polymorphism in the LTK kinase domain near YXXM, a binding motif of the p85 subunit of phosphatidylinositol 3-kinase (PI3K). SLE patients also had this type of Ltk polymorphism with a significantly higher frequency compared with the healthy controls. Our findings suggest that these polymorphic LTKs cause up-regulation of the PI3K pathway and possibly form one genetic component of susceptibility to abnormal proliferation of self-reactive B cells in SLE. 相似文献