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481.
The chemical and immunological properties of the cell walls prepared from the cells of anaerobic coryneforms, Propionibacterium acnes C7 and Corynebacterium parvum ATCC 11829, were partially investigated. The cell walls prepared from P. acnes C7 and C. parvum ATCC 11829 were composed of fatty acids, polysaccharides consisting glucose, galactose and mannose and mucopeptides consisting mainly of alanine, glutamic acid, a, ε-diaminopimelic acid, glycine, muramic acid and glucosamine. As the fatty acid constituents of the cell wall of P. acnes C7, iso-pentadecanoic acid and iso-heptadecanoic acid were detected as major components. Both cell walls prepared from P. acnes C7 and C. parvum ATCC 11829 showed potent adjuvant activity on the formation of circulating antibody and development of delayed type hypersensitivity in vivo and on the primary immune response to sheep erythrocytes in vitro, however, could not augment helper function of carrier-primed T cells and on the development of cell-mediated cytotoxicity to mastocytoma P815-X2 cells in C57BL/6J mice. It is also shown that the cell walls of P. acnes C7 and C. parvum ATCC 11829 act on mouse spleen cells as mitogen.  相似文献   
482.
The mutagenicities of aniline, o-toluidine and yellow OB were demonstrated only in the presence of the β-carboline compound, norharman. The effect of norharman increased linearly with increase in the amount of S-9. The mutagenicity of 4-dimethylaminoazobenzene was greatly enhanced by the presence of norharman, and again dose-dependency on the amount of S-9 was observed. In the presence of a large amount of S-9, norharman caused several fold enhancement of the mutagenicities of N-2-fluorenylacetamide, benzo(a)-pyrene, and 1,4-dimethyl-3-amino-5H-pyrido(4,3b) indole, isolated from a tryptophan pyrolysate. However, norharman suppressed the mutagenicities of these compounds in the presence of a small amount of S-9. The mutagenicity of kaempferol, a flavonoid, was inhibited by norharman with either a large or small amount of S-9.  相似文献   
483.
The effect of dietary restriction on sperm-head morphology in BDF1 mice was studied. The food intake of the ice was restricted to 2.0 or 1.5 g/day during the whole experimental period, while control animals were fed ad libitum. The average food intake of control mice was 4.2 ± 0.5 g/day. The frequencies of abnormal sperm in food-restricted mice remained at the basal level for the first 2 weeks. In week 3, the frequencies of abnormal sperm increased only in mice on the severely restricted diet (1.5 g/day). In week 5, the frequencies of abnormal sperm increased significantly in both restricted groups, and a negative correlation between the food intake and the frequency of abnormal sperm was observed. These results suggest that sperm abnormalities are not always the results of exogenous mutagen-induced damage  相似文献   
484.
The phenylpiperazine derivative naftopidil is an α1-adrenoceptor (AR) antagonist that has been used clinically to treat benign prostatic hyperplasia. In our drug repositioning research, naftopidil shows the unique growth-inhibitory effects. Naftopidil inhibits cell cycle progression not only in cancer cells, but also in fibroblasts and vascular endothelial cells. Naftopidil-inhibited cell cycle progression is independent of α1-AR expression in cells. Therefore, the antiproliferative effects of naftopidil may be due to the off-target effects of the drug. In this study, we attempted to identify the off-target molecules of naftopidil using the magnetic nanobeads, ferrite glycidyl metharcrylate (FG) beads. Similar to naftopidil, its derivatives TG09-01 and TG09-02, which were introduced with amino groups for immobilizing to FG beads, inhibited cell growth in human HT29 colon adenocarcinoma cells. Both derivatives were associated with inhibition of cell cycle progression in HT29 cells. This observation is consistent with that seen with naftopidil. Using TG09-02-immobilized FG beads, α- and β-tubulins were identified as the specific binding proteins of naftopidil. The tubulin polymerization assay clearly indicated that naftopidil bound directly to tubulin and inhibited the polymerization of tubulin. Other phenylpiperazine derivatives, such as RS100329, BMY7378, and KN-62, also inhibited the polymerization of tubulin. These results suggest that phenylpiperazine derivatives including naftopidil may have broad spectrum of cellular cytotoxicity in various types of cells. In addition, the tubulin polymerization-inhibiting activity of phenylpiperazine derivatives may be a specific feature of the phenylpiperazine-based structure. These findings can allow us to design and synthesize new tubulin-binding drugs derived from naftopidil as a lead compound.  相似文献   
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Thioredoxin (TRX) is known to contain an active site with aredox-active disulfide and has various biological activities. The objectiveof the present study was to investigate whether circulating TRX levels areelevated in patients with chronic hepatitis (CH) or liver cirrhosis (LC) andhepatocellular carcinoma (HCC). An anti-TRX monoclonal antibody andpolyclonal antibodies that specifically recognize TRX, were generated andused for the development of an ELlSA system to measure TRX levels in humanserum. The geometric mean and its 95% confidence interval of serumlevel of TRX in healthy volunteers was 81.75 ng/ml (74.60-89.59 ng/ml). Theserum level of TRX in LC/CH patients without HCC was 80.87 ng/ml(69.66-93.88 ng/ml). The value was not statistically different from that inserum from normal volunteers (p=0.69). In contrast, the serum level of TRXin patients with HCC was 147.35 ng/ml (125.53-1 72.96 ng/ml), which wassignificantly higher when compared with the level in serum of normalvolunteers (p<0.001) and in serum of LC/CH patients without HCC(p<0.001). In four patients with HCC, the initially high level of serum TRX(>150 ng/ml) decreased below 150 ng/ml after surgical removal of the tumor.The data reported herein revealed that patients with HCC had a significantlyelevated serum level of TRX, suggesting that measurement of serum of TRXmight be a useful clinical parameter when HCC is suspected.  相似文献   
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