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51.
Morita M Ishida N Uchiyama K Yamaguchi K Itoh Y Shichiri M Yoshida Y Hagihara Y Naito Y Yoshikawa T Niki E 《Free radical research》2012,46(6):758-765
An excessive accumulation of fat in the liver leads to chronic liver injury such as non-alcoholic fatty liver disease (NAFLD), which is an important medical problem affecting many populations worldwide. Oxidative stress has been implicated in the pathogenesis of NAFLD, but the exact nature of active species and the underlying mechanisms have not been elucidated. It was previously found that the administration of free radical-generating azo compound to mice induced accumulation of fat droplet in the liver. The present study was performed aiming at elucidating the changes of lipid classes and fatty acid composition and also measuring the levels of lipid peroxidation products in the liver induced by azo compound administration to mouse. The effects of azo compound on the liver were compared with those induced by high fat diet, a well-established cause of NAFLD. Azo compounds given to mice either by intraperitoneal administration or by dissolving to drinking water induced triacylglycerol (TG) increase and concomitant phospholipid decrease in the liver, whose pattern was quite similar to that induced by high fat diet. Lipid peroxidation products such as hydroxyoctadecadienoic acid and hydroxyeicosatetraenoic acid were increased in the liver in association with the increase in TG. These results show that free radicals as well as high fat diet induce fatty liver by similar mechanisms, in which lipid peroxidation may be involved. 相似文献
52.
Complete genomic sequence of nitrogen-fixing symbiotic bacterium Bradyrhizobium japonicum USDA110. 总被引:7,自引:0,他引:7
Takakazu Kaneko Yasukazu Nakamura Shusei Sato Kiwamu Minamisawa Toshiki Uchiumi Shigemi Sasamoto Akiko Watanabe Kumi Idesawa Mayumi Iriguchi Kumiko Kawashima Mitsuyo Kohara Midori Matsumoto Sayaka Shimpo Hisae Tsuruoka Tsuyuko Wada Manabu Yamada Satoshi Tabata 《DNA research》2002,9(6):189-197
The complete nucleotide sequence of the genome of a symbiotic bacterium Bradyrhizobium japonicum USDA110 was determined. The genome of B. japonicum was a single circular chromosome 9,105,828 bp in length with an average GC content of 64.1%. No plasmid was detected. The chromosome comprises 8317 potential protein-coding genes, one set of rRNA genes and 50 tRNA genes. Fifty-two percent of the potential protein genes showed sequence similarity to genes of known function and 30% to hypothetical genes. The remaining 18% had no apparent similarity to reported genes. Thirty-four percent of the B. japonicum genes showed significant sequence similarity to those of both Mesorhizobium loti and Sinorhizobium meliloti, while 23% were unique to this species. A presumptive symbiosis island 681 kb in length, which includes a 410-kb symbiotic region previously reported by G?ttfert et al., was identified. Six hundred fifty-five putative protein-coding genes were assigned in this region, and the functions of 301 genes, including those related to symbiotic nitrogen fixation and DNA transmission, were deduced. A total of 167 genes for transposases/104 copies of insertion sequences were identified in the genome. It was remarkable that 100 out of 167 transposase genes are located in the presumptive symbiotic island. DNA segments of 4 to 97 kb inserted into tRNA genes were found at 14 locations in the genome, which generates partial duplication of the target tRNA genes. These observations suggest plasticity of the B. japonicum genome, which is probably due to complex genome rearrangements such as horizontal transfer and insertion of various DNA elements, and to homologous recombination. 相似文献
53.
Kobayashi A Takanezawa Y Hirata T Shimizu Y Misasa K Kioka N Arai H Ueda K Matsuo M 《Journal of lipid research》2006,47(8):1791-1802
Cholesterol and phospholipids are essential to the body, but an excess of cholesterol or lipids is toxic and a risk factor for arteriosclerosis. ABCG1, one of the half-type ABC proteins, is thought to be involved in cholesterol homeostasis. To explore the role of ABCG1 in cholesterol homeostasis, we examined its subcellular localization and function. ABCG1 and ABCG1-K120M, a WalkerA lysine mutant, were localized to the plasma membrane in HEK293 cells stably expressing ABCG1 and formed a homodimer. A stable transformant expressing ABCG1 exhibited efflux of cholesterol and choline phospholipids in the presence of BSA, and the cholesterol efflux was enhanced by the presence of HDL, whereas cells expressing ABCG1-K120M did not, suggesting that ATP binding and/or hydrolysis is required for the efflux. Mass and TLC analyses revealed that ABCG1 and ABCA1 secrete several species of sphingomyelin (SM) and phosphatidylcholine (PC), and SMs were preferentially secreted by ABCG1, whereas PCs were preferentially secreted by ABCA1. These results suggest that ABCA1 and ABCG1 mediate the lipid efflux in different mechanisms, in which different species of phospholipids are secreted, and function coordinately in the removal of cholesterol and phospholipids from peripheral cells. 相似文献
54.
Chiharu Morita Kimisachi Tsuchiya Hiroshi Ueno Yasukazu Muramatsu Akiko Kojimahara Hitoshi Suzuki Nobumoto Miyashita Kazuo Moriwaki Mei-Lei Jin Xiang-Lin Wu Feng-Shan Wang 《Microbiology and immunology》1996,40(4):313-315
Serum samples from 337 wild house mice (Mus musculus) from 35 sites in China, collected in 1992 and 1993, were examined for antibodies against lymphocytic choriomeningitis virus (LCMV). Ten samples from eight sites were found to contain such antibodies. Six of the eight positive sites were located in the territory of M. m. gansuensis. One of the other two sites was located in the territory of M. m. castaneus in southern China and the other site was in a habitat of M. m. castaneus which had invaded into the western end of the territory of M. m. homourus. It seems likely that LCMV is distributed in the territories of M. m. gansuensis and M. m. castaneus in China. This is the first report of detection of these antibodies in wild house mice in China and specifically in the territories of M. m. gansuensis and M. m. castaneus. 相似文献
55.
Tsuyoshi Yanase Yasukazu Muramatsu Hiroshi Ueno Chiharu Morita 《Microbiology and immunology》1997,41(2):73-75
The prevalence and seasonal variations of infection by Coxiella burnetii in cattle were investigated seroepidemiologically on a farm in Hokkaido, Japan, by an immunofluorescent antibody test. A total of 364 serum samples from 28 cows were collected from August 1993 to October 1995 in two barns on the farm. It was found that the number of antibody-positive cows and their antibody titers were significantly elevated in winter and decreased in summer. In addition, antibodies were detectable in seroconverted cows for about five months. 相似文献
56.
Takeshi Obayashi Takashi Okegawa Yuko Sasaki-Sekimoto Hiroshi Shimada Tatsuru Masuda Erika Asamizu Yasukazu Nakamura Daisuke Shibata Satoshi Tabata Ken-ichiro Takamiya Hiroyuki Ohta 《DNA research》2004,11(1):11-25
The distinctive features of plant organs are primarily determined by organ-specific gene expression. We analyzed the expression specificity of 8809 genes in 7 organs of Arabidopsis using a cDNA macroarray system. Using relative expression (RE) values between organs, many known and unknown genes specifically expressed in each organ were identified. We also analyzed the organ specificity of various gene groups using the GRE (group relative expression) value, the average of the REs of all genes in a group. Consequently, we found that many gene groups even ribosomal protein genes, have strong organ-specific expression. Clustering of the expression profiles revealed that the 8809 genes were classified into 9 major categories. Although 3451 genes were clustered into the largest category, which showed constitutive gene expression, 266 and 1005 genes were found to be root- and silique-specific genes, respectively. By this clustering, particular gene groups which showed multi-organ-specific expression profiles, such as bud-flower-specific, stem-silique-specific or bud-flower-root-specific profiles, could be effectively identified. From these results, major features of plant organs could be characterized by their distinct profiles of global gene expression. These data of organ-specific gene expression are available at our web site: Arabidopsis thaliana Tissue-Specific Expression Database, ATTED (http://www.atted.bio.titech.ac.jp/). 相似文献
57.
Yasukazu Saitoh Minoru Ikeshima Naho Kawasaki Aoi Masumoto Nobuhiko Miwa 《Free radical research》2016,50(4):385-395
In our previous study, we demonstrated that combined treatment with hydrogen (H2) and platinum nanocolloid (Pt-nc) exerted markedly antiproliferative effects on cancer cells compared with each treatment alone. However, because the related mechanisms remain unclear, we investigated carcinostatic mechanisms of the combined treatment with H2 + Pt-nc. Significant suppression of cell proliferation was confirmed at 52?h following combined treatment, and the similar effect was also observed by the 30- or 40-min transient treatment with H2?+?Pt-nc. The transient treatments led to changes in cell size and morphology, loss of microvilli, and apoptosis-like cell death at 120 h after treatment. Moreover, transient combined treatment with H2?+?Pt-nc induced cell-cycle arrest, as reflected by decreased proportions of G1-phase cells and accumulation of G2/M-phase cells. In contrast, intracellular peroxide levels were temporarily and significantly increased immediately after H2?+?Pt-nc treatment but not after treatment with H2 or Pt-nc alone. Additionally, combined treatment-induced carcinostatic effects were significantly diminished in the presence of catalase, and marked hydrogen peroxide (H2O2) generation was confirmed after mixing Pt-nc into cell culture media containing a high concentration of H2. These changes are in agreement with the results that carcinostatic effects were induced after only 40 min of treatment with H2?+?Pt-nc. Thus, transient and marked generation of H2O2 is responsible for the carcinostatic effects of combined treatment with H2?+?Pt-nc. 相似文献
58.
Tomoo Enomoto Kiyoaki Matsubayashi Yasukazu Nagato Mayumi Nakano 《Primates; journal of primatology》1995,36(3):411-422
The degenerating pattern of spermatogenic cells in the seminiferous tubule of Japanese macaques was studied to clarify a relationship
between seasonal changes of reproductive performances and cytological findings in the Japanese macaque. For light microscopy,
testis samples were obtained from five adult animals by biopsy in April (nonmating season) and October (mating season). For
electron microscopy, specimens from four additional macaques were used. Degenerating cells were found in all steps of spermatogenesis.
In stages I to V of the cycle of the seminiferous epithelium, morphologically atypical pachytene spermatocytes were observed
in 14.7 and 10.0% of the cells in the nonmating and mating seasons, respectively, although the difference in percentage was
not significant. Mature spermatids with atypical features in those stages occupied 59.6% of the cells in the nonmating season,
which significantly decreased to 34.1% in the mating season. These results imply that the seasonal change of sperm production
is related, at least in part, to the process of degeneration of the spermatogenic cells in this species. 相似文献
59.
Hisano Hiroshi; Sato Shusei; Isobe Sachiko; Sasamoto Shigemi; Wada Tsuyuko; Matsuno Ai; Fujishiro Tsunakazu; Yamada Manabu; Nakayama Shinobu; Nakamura Yasukazu; Watanabe Satoshi; Harada Kyuya; Tabata Satoshi 《DNA research》2007,14(6):271-281
We generated a high-density genetic linkage map of soybean usingexpressed sequence tag (EST)-derived microsatellite markers.A total of 6920 primer pairs (10.9%) were designed to amplifysimple sequence repeats (SSRs) from 63 676 publicly availablenon-redundant soybean ESTs. The polymorphism of two parent plants,the Japanese cultivar Misuzudaizu and the Chineseline Moshidou Gong 503, were examined using 10%polyacrylamide gel electrophoresis. Primer pairs showing polymorphismwere then used for genotyping 94 recombinant inbred lines (RILs)derived from a cross between the parents. In addition to previouslyreported markers, 680 EST-derived microsatellite markers wereselected and subjected to linkage analysis. As a result, 935marker loci were mapped successfully onto 20 linkage groups,which totaled 2700.3 cM in length; 693 loci were detected usingthe 668 EST-derived microsatellite markers developed in thisstudy, the other 242 loci were detected with 105 RFLP markers,136 genome-derived microsatellite markers, and one phenotypicmarker. We examined allelic variation among 23 soybean cultivars/linesand a wild soybean line using 668 mapped EST-derived microsatellitemarkers (corresponding to 686 marker loci), in order to determinethe transferability of the markers among soybean germplasms.A limited degree of macrosynteny was observed at the segmentallevel between the genomes of soybean and the model legume Lotusjaponicus, which suggests that considerable genome shufflingoccurred after separation of the species and during establishmentof the paleopolyploid soybean genome. 相似文献
60.
KH Takahashi Y Okada K Teramura 《Evolution; international journal of organic evolution》2012,66(9):2878-2890
Environmental canalization is defined as a reduction in the effect of external environmental perturbations on a phenotype, while phenotypic plasticity is defined as the production of different phenotypes in alternative environments. These terms describe different aspects of the same phenomenon, that is, the sensitivity of the phenotype to the environment. Genetic regulation of the environmental sensitivity has been a central topic in the field of evolutionary biology. In this study, we performed deficiency screening to detect genomic regions with effects on the environmental sensitivity of Drosophila melanogaster sensory bristles. We used a collection of isogenic deficiency strains established by the DrosDel Project for screening. We screened 423 genomic deficiencies that encompassed approximately 63.6% of the entire D. melanogaster genome. We identified 29 genomic deficiencies showing significant effects on environmental sensitivity, suggesting that multiple genomic regions may influence phenotypic variation. We also found significant correlations among the effects of deficiencies on environmental sensitivity for different bristle traits, suggesting that the same genetic mechanism can regulate environmental sensitivity of multiple traits. Current high-resolution mapping will facilitate the examination of individual candidate genes using mutations or RNAi approaches in future studies. 相似文献