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191.
192.
Reiko Kuroda Hiroaki Higuchi Keishirou Yoshida Yasunori Yonejima Keiko Hisa Masanori Utsuyama Kenji Osawa Katsuiku Hirokawa 《Immunity & ageing : I & A》2018,15(1):29
Background
Previous reports showed that oral administration of Leuconostoc mesenteroides strain NTM048 increases IgA levels and CD4+ T cell population in feces and mice, respectively, as revealed by flow cytometric analysis of splenocytes. This study aimed to evaluate the effect of chocolate supplemented with L. mesenteroides strain NTM048 (>?1.00?×?109?CFU/day, NTM048) on the immune parameters of healthy subjects, using a randomized, placebo-controlled, double-blinded study design.Methods
Participants (mean age: 46.3?years) ingested 28?g of test food daily, at a time of their own choice, for 4?weeks. The immunological parameters of all participants were evaluated two times (pre- and post- ingestion). At the end of the study, various immunological parameters of the participants were measured and scoring of immunological vigor (SIV) was performed using a comprehensive algorithm.Results
Ingestion of NTM048-supplemented chocolate significantly improved SIV in the NTM048 group (18.6?±?1.6) compared to that in the placebo group (17.8?±?2.0) after 4?weeks (p?=?0.049). Several immunological parameters (CD8+T cells, CD8+CD28+ T cells, and memory T cells) were significantly elevated in the NTM048 group as compared to the placebo group (all p?<?0.05). In addition, T cell proliferation index at post-ingestion significantly increased compared with that at pre-ingestion in the NTM048 (p?=?0.017) and placebo groups (p?=?0.037), although no differences were observed between the two groups.Conclusion
Our results suggest that ingestion of chocolate supplemented with NTM048 is effective against the age-related decline in T cell-related immune functions.Trial registration
UMIN Clinical Trials Registry UMIN000021989. Registered 19 April 2016, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000025321193.
Production of thermostable direct hemolysin by Vibrio parahaemolyticus enhanced by conjugated bile acids. 总被引:2,自引:0,他引:2 下载免费PDF全文
The effects of conjugated bile acids, glycocholic acid, and taurocholic acid (TC) on production of thermostable direct hemolysin (TDH) by Vibrio parahaemolyticus were determined by a reversed passive latex agglutination assay against TDH. The amount of TDH excreted in growth medium containing either glycocholic acid or taurocholic acid (5 mM/liter) was, on a per-cell basis, 4- to 16-fold greater than that excreted in medium without the bile acids. The amounts of TDH released from lysed cells grown with the bile acids (5 mM/liter) were 4- to 32-fold greater than those from lysed cells grown without, suggesting that the bile acids enhanced synthesis of TDH within bacterial cells. These data imply that the conjugated bile acids play a key role in the pathogenicity of V. parahaemolyticus. 相似文献
194.
Metabolic inactivation of retinoic acid by a novel P450 differentially expressed in developing mouse embryos. 总被引:9,自引:2,他引:7 下载免费PDF全文
H Fujii T Sato S Kaneko O Gotoh Y Fujii-Kuriyama K Osawa S Kato H Hamada 《The EMBO journal》1997,16(14):4163-4173
Retinoic acid (RA) is a physiological agent that has a wide range of biological activity and appears to regulate developmental programs of vertebrates. However, little is known about the molecular basis of its metabolism. Here we have identified a novel cytochrome P450 (P450RA) that specifically metabolizes RA. In vitro, P450RA converts all-trans RA into 5,8-epoxy all-trans RA. P450RA metabolizes other biologically active RAs such as 9-cis RA and 13-cis RA, but fails to metabolize their precursors, retinol and retinal. Overexpression of P450RA in cell culture renders the cells hyposensitive to all-trans RA. These functional tests in vitro and in vivo indicate that P450RA inactivates RA. The P450RA gene is not expressed uniformly but in a stage- and region-specific fashion during mouse development. The major expression domains in developing embryos include the posterior neural plate and neural crest cells for cranial ganglia. The expression of P450RA, however, is not necessarily inducible by excess RA. These results suggest that P450RA regulates the intracellular level of RA and may be involved in setting up the uneven distribution of active RA in mammalian embryos. 相似文献
195.
A total of 18 strains of V. parahaemolyticus
isolated from patients of past food poisoning cases occurring in Kanagawa
Prefecture, Japan, were assayed for presence of the thermostable direct
hemolysin (TDH) gene and the TDH-related hemolysin (TRH) genes (trh 1
and trh 2) with specific reference to their ability to hydrolyze urea
and TDH production. A polymerase chain reaction assay revealed that all
urea-hydrolyzing strains (9 strains) carried either trh 1 gene or
trh 2 gene. The strains carrying the trh genes as well as the
tdh gene produced TDH less by a factor of 4 to 16 than those carrying
only the tdh gene, suggesting the expression of the tdh gene
was suppressed by the presence of trh gene through a mechanism yet to
be defined.
Received: 20 September 1996 / Accepted: 6 November 1996 相似文献
196.
Freshwater planarians Dugesia japonica from three localities were examined for cytochrome c oxidase subunit I (COI) gene sequence, karyotype and the presence of genital organ. The planarians from Mt Fujiwara in Japan were composed of two different groups; one revealed inter- and intraindividual COI gene heterogeneity, while another revealed no sequence heterogeneity. The sequence in planarians from Mt Alishan in Taiwan was homogeneous, while that from the Kenting National Park in Taiwan revealed a considerable heterogeneity. All the planarians having the homogeneous gene sequences carry the 2X karyotype and many of them had genital organs. These are assumed to belong to the sexual lineage. In contrast, almost all planarians having heterogeneous sequences carry the karyotype of either 3X plus 2X (mixoploid) or 3X, and all of them lack genital organs. These lineages are assumed to be asexual. The heterogeneity of COI gene sequences in the presumed asexual lineages would have resulted from an accumulation of mutations by repeated asexual reproduction. 相似文献
197.
198.
The enterohepatic circulation and metabolism of ethynodiol diacetate (3beta,17beta-diacetoxy-17alpha-ethynyl-estr-4-ene) in baboons were studied following the intravenous injection of this contraceptive steroid labeled with 14C (4-position) and with 3H (in either the 3- or 17-acetoxy moieties). Bile and urine from four baboons with biliary fistulas and urine from four intact baboons were collected for 7 hours. On the average, 40% and 44% of the injected dose were excreted in the bile and urine, respectively. Only 48% was recovered in the urine of intact baboons. Analysis of these excretion rates indicates an insignificant enterohepatic circulation of this compound. The steroid was excreted mostly (over 80%) as a glucosiduronate in urine and bile. Very little excretion of the 3-acetoxy compound was detected in the urine or bile at any time interval. 17-Monoacetoxy compounds, however, were detected both in urine and bile, suggesting a difference in the rate of in vivo hydrolysis of the 17beta- vs. the 3beta-acetate. 相似文献
199.
200.
The ribosomal protein gene cluster of Mycoplasma capricolum 总被引:15,自引:0,他引:15
Shoichi Ohkubo Akira Muto Yasushi Kawauchi Fumiaki Yamao Syozo Osawa 《Molecular & general genetics : MGG》1987,210(2):314-322
Summary The DNA sequence of the part of the Mycoplasma capricolum genome that contains the genes for 20 ribosomal proteins and two other proteins has been determined. The organization of the gene cluster is essentially the same as that in the S10 and spc operons of Escherichia coli. The deduced amino acid sequence of each protein is also well conserved in the two bacteria. The G+C content of the M. capricolum genes is 29%, which is much lower than that of E. coli (51%). The codon usage pattern of M. capricolum is different from that of E. coli and extremely biased to use of A and U(T): about 91% of codons have A or U in the third position. UGA, which is a stop codon in the universal code, is used more abundantly than UGG to dictate tryptophan. 相似文献