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71.
Structural study of isoflavonoids possessing antioxidant activity isolated from the fermentation broth of Streptomyces sp 总被引:1,自引:0,他引:1
Structures of three antioxidant isoflavonoids isolated from the cultured broth of Streptomyces sp. OH-1049 were shown to be 4',7,8-trihydroxyisoflavone (1), 3',4',7-trihydroxyisoflavone (2) and 8-chloro-3',4',5,7-tetrahydroxyisoflavone (3), respectively. Among them, 3 is a novel isoflavonoid possessing a chlorine atom in the molecule. Compound 1 was synthesized and its antitumor activities were tested against IMC carcinoma, S180, P388 leukemia and P388/ADM leukemia in vivo. As a result, 1 showed 139% increase in life span (ILS) against S180 bearing mice whereas it showed slight or no ILS against IMC carcinoma, P388 leukemia and P388/ADM leukemia bearing mice. 相似文献
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Y Hitoshi S Mita A Tominaga Y Kikuchi E Sonoda K Takatsu Y Watanabe 《International immunology》1989,1(2):185-190
Interferon-gamma (IFN-gamma) is supposed to be produced by type 1 helper T cells (TH1) and inhibits IL-4-dependent B cell growth and differentiation. IL-5 (T cell-replacing factor, TRF), is a T cell-derived lymphokine which is predominantly produced by type 2 helper T cells (TH2) and regulates proliferation and differentiation of activated B cells. In this study, the effect of IFN-gamma on IL-5-dependent B cell growth and differentiation has been studied using murine chronic B cell leukemic cells (BCL1), normal splenic B cells, and cloned early B cell line. IFN-gamma selectively inhibits the IL-5-mediated proliferation of activated B cells as well as cloned early B cell lines at a low concentration (2 U/ml) in which polyclonal IgM production was not affected. This inhibitory effect of IFN-gamma occurs within 24 h after the onset of culture, as demonstrated by the inability of antibody to IFN-gamma to reverse totally the IFN-gamma-mediated suppressive effects if it was added later than 24 h after the onset of the culture. On the contrary, IL-5-mediated IgM secretion of BCL1 and IgA formation of LPS-stimulated normal B cells were relatively resistant to the suppressive effect of IFN-gamma. IFN-gamma does not affect the receptor expression for IL-5. Interestingly, IL-4-mediated IgG1 formation of LPS-stimulated B cells was markedly suppressed by IFN-gamma at 10 U/ml. These results strongly suggest that IFN-gamma may have differential effects on IL-5-mediated B cell triggering. 相似文献
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Shiho Nakayama Hirotaka Watada Tomoya Mita Fuki Ikeda Tomoaki Shimizu Hiroshi Uchino Yoshio Fujitani Takahisa Hirose Ryuzo Kawamori 《Hypertension research》2008,31(1):7-13
Angiotensin II type-1 receptor blockers (ARBs) are regarded as first-line treatments for type-2 diabetes with hypertension. Despite the availability of various types of ARBs, there are no comparative studies of their effects on patients with diabetes. In this open-label prospective crossover study, we compared the effects of olmesartan (20 mg/day) and telmisartan (40 mg/day). Twenty Japanese early-stage type-2 diabetes patients with hypertension treated with valsartan (80 mg/day) for at least 8 weeks were recruited to this study. At study entry, valsartan was changed to olmesartan (20 mg/day) or telmisartan (40 mg/day) and administered for 8 weeks. The drugs were then switched and treatment was continued for another 8 weeks. We analyzed the blood pressure lowering effects of each drug by 24-h ambulatory blood pressure monitoring at 0, 8, and 16 weeks. Simultaneously, we measured metabolic parameters and inflammation markers. Olmesartan lowered mean systolic and diastolic blood pressure more significantly than did telmisartan. While there were no differences between the groups in metabolic parameters, including HbA1c and adiponectin, the decreases in serum interleukin-6 and highly sensitive C-reactive protein were more significant by olmesartan treatment. Our results indicate that olmesartan has more potent arterial blood pressure lowering and anti-inflammatory effects than telmisartan. 相似文献
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H Uchida K Mita Y Bekku Y Nishimura Y Ishida K Watanabe S Tomikawa S Inoue H Sugimoto T Nagao 《The Journal of toxicological sciences》1991,16(4):181-190
Mizoribine (Mz) is an analogue of azathioprine (Az) with less hepatotoxicity, being extensively used as immunosuppressant in place of the latter agent especially in Japan. However, careful comparative studies of mizoribine (Mz), cyclosporine (Cy), and prednisolone (Pr) versus azathioprine (Az), Cy and Pr or Cy and Pr in renal allotranspalnt patients have not been reported. Retrospectively we compared triple therapy with Mz, Cy, and Pr (group I, n = 50) to triple therapy with Az, Cy and Pr (group II, n = 13) and/or double therapy with Cy and Pr (group III, n = 11) in one-haplotype-identical living related renal transplantations performed between Oct. 1984 through March 1989. Initial and maintenance doses of Cy in groups I and II were largely two thirds of those in group III. Patient and graft survival rates at 3 years in each group are 100% and 92% (group I), 100% and 91% (group II), and 91% and 82% (group III). There were no statistical differences in patient and graft survival rates between these three groups. The incidences of miscellaneous complications were the same in the groups. Bone marrow suppression, however, was significantly less in group I than in group II (P less than 0.005). Cy related nephrotoxicity was apparently less in groups I and II than in group III. Estimated US $5,000 in a year can be saved by immunosuppressive treatment in a patient of group I as compared to a patient in group III. Therefore, we conclude that triple therapy with Mz, Cy and Pr is superior to those with Az, Cy and Pr, and/or double therapy with Cy and Pr. 相似文献
78.
Yosuke Mita Ryo Inose Ryota Goto Yoshiki Kusama Ryuji Koizumi Daisuke Yamasaki Masahiro Ishikane Masaki Tanabe Norio Ohmagari Yuichi Muraki 《Journal of infection and chemotherapy》2021,27(7):972-976
IntroductionAnti-methicillin-resistant Staphylococcus aureus (MRSA) agents have different doses and administration periods. Thus, it is difficult to evaluate antimicrobial use (AMU) of anti-MRSA agents using defined daily doses per 1000 inhabitants per day (DID) or days of therapy per 1000 inhabitants per day (DOTID). This study aimed to evaluate the relationship between anti-MRSA agent use and resistant bacteria using the number of patients per 1000 inhabitants per day (PID) as an alternative index of AMU.MethodsAMU data for anti-MRSA agents were collected from the National Database of Health Insurance Claims and Specific Health Checkups (NDB) in 2016. The relationship between PID and DID or DOTID was evaluated. The number of patients with MRSA isolated was obtained from Japan Nosocomial Infections Surveillance, and their correlation with PID was analyzed. The rate of anti-MRSA agent use in each prefecture was investigated.ResultsPID showed a significant linear relationship with both DID and DOTID (all p < 0.0001). PID was significantly correlated with the number of patients with MRSA isolated. Additionally, the rate of anti-MRSA agent use was markedly different in each region.ConclusionsPID is not affected by doses and administration periods, and thus may be an alternative index for the selective pressure of antibiotics. Evaluating AMU using PID based on NDB data will help in the development of effective antimicrobial resistance measures. 相似文献
79.
T. Goda S. Takase H. Yokogoshi T. Mita M. Isemura T. Hoshi 《Zeitschrift für die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie》1991,191(1):189-199
The effect of simulated weightlessness on hepatic metabolisms of carbohydrates and lipids was investigated in rats that were
chronically immobilized by means of a suspension harness. During the 10-day period of the suspension, the animals showed a
substantial decrease in the hepatic glycogen content, whereas the content of hepatic total lipids was markedly elevated. Similar
results were obtained when the “suspended” animals were provided with a regular amount of nutrients by a force-feeding procedure.
In the suspended animals, hepatic parenchymal cells were filled with large fat droplets, and hepatic triglyceride contents
were elevated. The prolonged immobilization led to a slight, but significant, increase in glucose-6-phosphatase activity in
the liver, suggesting that an increased glycogen breakdown might have occurred in the suspended animals. However, it was unlikely
that the increased amount of glucose produced by the glycogen breakdown was utilized as a substrate for the lipogenesis in
the liver, because hepatic lipogenic enzyme activities were unaffected by the suspension. The results suggest that the hepatic
lipids accumulate in animals exposed to a prolonged immobilization state, presumably due to a decreased lipolysis and/or a
suppressed lipoprotein mobilization from the liver into the blood stream. 相似文献
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