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排序方式: 共有1521条查询结果,搜索用时 41 毫秒
41.
Teruhisa Uwatoko Miho Yoshizumi Jun Miyata Shiho Ubukata Hironobu Fujiwara Ryosaku Kawada Manabu Kubota Akihiko Sasamoto Genichi Sugihara Toshihiko Aso Shinichi Urayama Hidenao Fukuyama Toshiya Murai Hidehiko Takahashi 《PloS one》2015,10(11)
Improving quality of life has been recognized as an important outcome for schizophrenia treatment, although the fundamental determinants are not well understood. In this study, we investigated the association between brain structural abnormalities and objective quality of life in schizophrenia patients. Thirty-three schizophrenia patients and 42 age-, sex-, and education-matched healthy participants underwent magnetic resonance imaging. The Quality of Life Scale was used to measure objective quality of life in schizophrenia patients. Voxel-based morphometry was performed to identify regional brain alterations that correlate with Quality of Life Scale score in the patient group. Schizophrenia patients showed gray matter reductions in the frontal, temporal, limbic, and subcortical regions. We then performed voxel-based multiple regression analysis in these regions to identify any correlations between regional gray matter volume and Quality of Life Scale scores. We found that among four subcategories of the scale, the Instrumental Role category score correlated with gray matter volume in the right anterior insula in schizophrenia patients. In addition, this correlation was shown to be mediated by negative symptoms. Our findings suggest that the neural basis of objective quality of life might differ topographically from that of subjective QOL in schizophrenia. 相似文献
42.
Aya Obana-Koshino Hitomi Ono Jiro Miura Manabu Sakai Hitoshi Uchida Wataru Nakamura Kanji Nohara Yusuke Maruyama Atsuhiko Hattori Takayoshi Sakai 《PloS one》2015,10(4)
Many organs, including salivary glands, lung, and kidney, are formed by epithelial branching during embryonic development. Branching morphogenesis occurs via either local outgrowths or the formation of clefts that subdivide epithelia into buds. This process is promoted by various factors, but the mechanism of branching morphogenesis is not fully understood. Here we have defined melatonin as a potential negative regulator or “brake” of branching morphogenesis, shown that the levels of it and its receptors decline when branching morphogenesis begins, and identified the process that it regulates. Melatonin has various physiological functions, including circadian rhythm regulation, free-radical scavenging, and gonadal development. Furthermore, melatonin is present in saliva and may have an important physiological role in the oral cavity. In this study, we found that the melatonin receptor is highly expressed on the acinar epithelium of the embryonic submandibular gland. We also found that exogenous melatonin reduces salivary gland size and inhibits branching morphogenesis. We suggest that this inhibition does not depend on changes in either proliferation or apoptosis, but rather relates to changes in epithelial cell adhesion and morphology. In summary, we have demonstrated a novel function of melatonin in organ formation during embryonic development. 相似文献
43.
Shusuke Numata Kazuo Ishii Atsushi Tajima Jun-ichi Iga Makoto Kinoshita Shinya Watanabe Hidehiro Umehara Manabu Fuchikami Satoshi Okada Shuken Boku Akitoyo Hishimoto Shinji Shimodera Issei Imoto Shigeru Morinobu Tetsuro Ohmori 《Epigenetics》2015,10(2):135-141
Aberrant DNA methylation in the blood of patients with major depressive disorder (MDD) has been reported in several previous studies. However, no comprehensive studies using medication-free subjects with MDD have been conducted. Furthermore, the majority of these previous studies has been limited to the analysis of the CpG sites in CpG islands (CGIs) in the gene promoter regions. The main aim of the present study is to identify DNA methylation markers that distinguish patients with MDD from non-psychiatric controls. Genome-wide DNA methylation profiling of peripheral leukocytes was conducted in two set of samples, a discovery set (20 medication-free patients with MDD and 19 controls) and a replication set (12 medication-free patients with MDD and 12 controls), using Infinium HumanMethylation450 BeadChips. Significant diagnostic differences in DNA methylation were observed at 363 CpG sites in the discovery set. All of these loci demonstrated lower DNA methylation in patients with MDD than in the controls, and most of them (85.7%) were located in the CGIs in the gene promoter regions. We were able to distinguish patients with MDD from the control subjects with high accuracy in the discriminant analysis using the top DNA methylation markers. We also validated these selected DNA methylation markers in the replication set. Our results indicate that multiplex DNA methylation markers may be useful for distinguishing patients with MDD from non-psychiatric controls. 相似文献
44.
Tomohito Sato Manabu Kinoshita Tetsuo Yamamoto Masataka Ito Takafumi Nishida Masaru Takeuchi Daizoh Saitoh Shuhji Seki Yasuo Mukai 《PloS one》2015,10(2)
Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure. 相似文献
45.
Satoi Nagasawa Anna S. Sedukhina Yuko Nakagawa Ichiro Maeda Manabu Kubota Shigeko Ohnuma Koichiro Tsugawa Tomohiko Ohta Marta Roche-Molina Juan A. Bernal Ana J. Narváez Anand D. Jeyasekharan Ko Sato 《PloS one》2015,10(2)
LSD1, a lysine-specific histone demethylase, is overexpressed in several types of cancers and linked to poor outcomes. In breast cancer, the significance of LSD1 overexpression is not clear. We have performed an in silico analysis to assess the relationship of LSD1 expression to clinical outcome. We demonstrate that LSD1 overexpression is a poor prognostic factor in breast cancer, especially in basal-like breast cancer, a subtype of breast cancer with aggressive clinical features. This link is also observed in samples of triple negative breast cancer. Interestingly, we note that overexpression of LSD1 correlates with down-regulation of BRCA1 in triple negative breast cancer. This phenomenon is also observed in in vitro models of basal-like breast cancer, and is associated with an increased sensitivity to PARP inhibitors. We propose therefore that high expression levels of the demethylase LSD1 is a potential prognostic factor of poor outcome in basal-like breast cancer, and that PARP inhibition may be a therapeutic strategy of interest in this poor prognostic subtype with overexpression of LSD1. 相似文献
46.
Ana F. Pinto Smilja Todorovic Peter Hildebrandt Manabu Yamazaki Fumio Amano Shizunobu Igimi Célia V. Romão Miguel Teixeira 《Journal of biological inorganic chemistry》2011,16(3):501-510
A novel multidomain metalloprotein from Campylobacter jejuni was overexpressed in Escherichia coli, purified, and extensively characterized. This protein is isolated as a homotetramer of 24-kDa monomers. According to the
amino acid sequence, each monomer was predicted to contain three structural domains: an N-terminal desulforedoxin-like domain,
followed by a four-helix bundle domain harboring a non-sulfur μ-oxo diiron center, and a rubredoxin-like domain at the C-terminus.
The three predicted iron sites were shown to be present and were studied by a combination of UV–vis, EPR, and resonance Raman
spectroscopies, which allowed the determination of the electronic and redox properties of each site. The protein contains
two FeCys4 centers with reduction potentials of +240 mV (desulforedoxin-like center) and +185 mV (rubredoxin-like center). These centers
are in the high-spin configuration in the as-isolated ferric form. The protein further accommodates a μ-oxo-bridged diiron
site with reduction potentials of +270 and +235 mV for the two sequential redox transitions. The protein is rapidly reoxidized
by hydrogen peroxide and has a significant NADH-linked hydrogen peroxide reductase activity of 1.8 μmol H2O2 min−1 mg−1. Owing to its building blocks and its homology to the rubrerythrin family, the protein is named desulforubrerythrin. It represents
a novel example of the large diversity of the organization of domains exhibited by this enzyme family. 相似文献
47.
48.
Masabumi Funakoshi Manabu Tsuda Keigo Muramatsu Hiroshi Hatsuda Shinichi Morishita Toshiro Aigaki 《Biochemical and biophysical research communications》2011,(4):214
The insulin/insulin-like growth factor (IGF) and the target of rapamycin (TOR) signaling pathways are known to regulate lifespan in diverse organisms. However, only a limited number of genes involved in these pathways have been examined regarding their effects on lifespan. Through a gain-of-function screen in Drosophila, we found that overexpression of the wdb gene encoding a regulatory subunit of PP2A, and overexpression of the lkb1 gene encoding a serine/threonine kinase, reduced organ size and extended lifespan. Overexpression of wdb also reduced the level of phosphorylated AKT, while overexpression of lkb1 increased the level of phosphorylated AMPK and decreased the level of phosphorylated S6K. Taken together, our results suggest that wdb- and lkb1-dependent lifespan extension is mediated by downregulation of S6K, a downstream component of the insulin/IGF and TOR signaling pathways. 相似文献
49.
Akira Kubota Fang He Manabu Kawase Gaku Harata Masaru Hiramatsu Hisakazu Iino 《Current microbiology》2011,62(1):71-77
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis
(JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis
patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with
16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented
milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and
quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with
more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that
lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target
for using probiotics in the management of IgE-mediated allergic disorders including JCPsis. 相似文献
50.