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951.
Yutaka Ono Akio Sakai Kotaro Otsuka Hidenori Uda Hirofumi Oyama Naoki Ishizuka Shuichi Awata Yasushi Ishida Hiroto Iwasa Yuichi Kamei Yutaka Motohashi Jun Nakamura Nobuyuki Nishi Naoki Watanabe Toshihiko Yotsumoto Atsuo Nakagawa Yuriko Suzuki Miyuki Tajima Eriko Tanaka Hironori Sakai Naohiro Yonemoto 《PloS one》2013,8(10)
Background
Multilevel and multimodal interventions have been suggested for suicide prevention. However, few studies have reported the outcomes of such interventions for suicidal behaviours.Methods
We examined the effectiveness of a community-based multimodal intervention for suicide prevention in rural areas with high suicide rates, compared with a parallel prevention-as-usual control group, covering a total of 631,133 persons. The effectiveness was also examined in highly populated areas near metropolitan cities (1,319,972 persons). The intervention started in July 2006, and continued for 3.5 years. The primary outcome was the incidence of composite outcome, consisting of completed suicides and suicide attempts requiring admission to an emergency ward for critical care. We compared the rate ratios (RRs) of the outcomes adjusted by sex, age group, region, period and interaction terms. Analyses were performed on an intention-to-treat basis and stratified by sex and age groups.Findings
In the rural areas, the overall median adherence of the intervention was significantly higher. The RR of the composite outcome in the intervention group decreased 7% compared with that of the control group. Subgroup analyses demonstrated heterogeneous effects among subpopulations: the RR of the composite outcome in the intervention group was significantly lower in males (RR = 0.77, 95% CI 0.59–0.998, p = 0.0485) and the RR of suicide attempts was significantly lower in males (RR = 0.39, 95% CI 0.22–0.68, p = 0.001) and the elderly (RR = 0.35, 95% CI 0.17–0.71, p = 0.004). The intervention had no effect on the RR of the composite outcome in the highly populated areas.Interpretation
Our findings suggest that this community-based multimodal intervention for suicide prevention could be implemented in rural areas, but not in highly populated areas. The effectiveness of the intervention was shown for males and for the elderly in rural areas.Trial Registration
ClinicalTrials.gov UMIN Clinical Trials Registry NCT00737165UMIN000000460 相似文献952.
Masaaki Murakami Masaya Harada Daisuke Kamimura Hideki Ogura Yuko Okuyama Noriko Kumai Azusa Okuyama Rajeev Singh Jing-Jing Jiang Toru Atsumi Sayaka Shiraya Yuji Nakatsuji Makoto Kinoshita Hitoshi Kohsaka Makoto Nishida Saburo Sakoda Nobuyuki Miyasaka Keiko Yamaguchi-Takihara Toshio Hirano 《Cell reports》2013,3(3):946-959
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953.
Miki Ota Hiroshi Sakuragi Hironobu Morisaka Kouichi Kuroda Hideo Miyake Yutaka Tamaru Mitsuyoshi Ueda 《Biotechnology progress》2013,29(2):346-351
Xylose isomerase (XI) is a key enzyme in the conversion of d ‐xylose, which is a major component of lignocellulosic biomass, to d ‐xylulose. Genomic analysis of the bacterium Clostridium cellulovorans revealed the presence of XI‐related genes. In this study, XI derived from C. cellulovorans was produced and displayed using the yeast cell‐surface display system, and the xylose assimilation and fermentation properties of this XI‐displaying yeast were examined. XI‐displaying yeast grew well in medium containing xylose as the sole carbon source and directly produced ethanol from xylose under anaerobic conditions. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 346–351, 2013 相似文献
954.
Tetsuaki Ishikawa Fumie Itoh Sayumi Yoshida Shinobu Saijo Tetsuhiro Matsuzawa Tohru Gonoi Takashi Saito Yoshio Okawa Nobuyuki Shibata Tomofumi Miyamoto Sho Yamasaki 《Cell host & microbe》2013,13(4):477-488
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955.
Takayuki Imai Keiichi Tamai Sayuri Oizumi Kyoko Oyama Kazunori Yamaguchi Ikuro Sato Kennichi Satoh Kazuto Matsuura Shigeru Saijo Kazuo Sugamura Nobuyuki Tanaka 《PloS one》2013,8(4)
Cancer stem cells contribute to the malignant phenotypes of a variety of cancers, but markers to identify human hypopharyngeal cancer (HPC) stem cells remain poorly understood. Here, we report that the CD271+ population sorted from xenotransplanted HPCs possesses an enhanced tumor-initiating capability in immunodeficient mice. Tumors generated from the CD271+ cells contained both CD271+ and CD271− cells, indicating that the population could undergo differentiation. Immunohistological analyses of the tumors revealed that the CD271+ cells localized to a perivascular niche near CD34+ vasculature, to invasive fronts, and to the basal layer. In accordance with these characteristics, a stemness marker, Nanog, and matrix metalloproteinases (MMPs), which are implicated in cancer invasion, were significantly up-regulated in the CD271+ compared to the CD271− cell population. Furthermore, using primary HPC specimens, we demonstrated that high CD271 expression was correlated with a poor prognosis for patients. Taken together, our findings indicate that CD271 is a novel marker for HPC stem-like cells and for HPC prognosis. 相似文献
956.
Nobuyuki Kurosawa Rika Fujimoto Tatsuhiko Ozawa Takahiro Itoyama Naoki Sadamori Masaharu Isobe 《PloS one》2013,8(1)
Background
Adult T-cell leukemia/lymphoma (ATLL) develops in a small proportion of human T-cell leukemia virus type I (HTLV-I)-infected individuals. However, the mechanism by which HTLV-I causes ATLL has not been fully elucidated. To provide fundamental insights into the multistep process of leukemogenesis, we have mapped the chromosomal abnormalities in 50 ATLL cases to identify potential key regulators of ATLL.Results
The analysis of breakpoints in one ATLL case with the translocations t(14;17)(q32;q22-23) resulted in the identification of a Kruppel zinc finger gene, BCL11B, which plays a crucial role in T-cell development. Among the 7 ATLL cases that we examined by immunofluorescence analysis, 4 displayed low and one displayed moderate BCL11B signal intensities. A dramatically reduced level of the BCL11B protein was also found in HTLV-I-positive T-cell lines. The ectopic expression of BCL11B resulted in significant growth suppression in ATLL-derived cell lines but not in Jurkat cells.Conclusions
Our genetic and functional data provide the first evidence that a reduction in the level of the BCL11B protein is a key event in the multistep progression of ATLL leukemogenesis. 相似文献957.
Yasumi Uchida Yuko Maezawa Yasuto Uchida Nobuyuki Hiruta Ei Shimoyama Seiji Kawai 《PloS one》2013,8(2)
Objectives
Oxidized low-density lipoprotein (oxLDL) plays a key role in the formation of atherosclerotic plaques. However, its localization in human coronary arterial wall is not well understood. The present study was performed to visualize deposition sites and patterns of native oxLDL and their relation to plaque morphology in human coronary artery.Methods
Evans blue dye (EB) elicits a violet fluorescence by excitation at 345-nm and emission at 420-nm, and a reddish-brown fluorescence by excitation at 470-nm and emission at 515-nm characteristic of oxLDL only. Therefore, native oxLDL in excised human coronary artery were investigated by color fluorescent microscopy (CFM) using EB as a biomarker.Results
(1) By luminal surface scan with CFM, the % incidence of oxLDL in 38 normal segments, 41 white plaques and 32 yellow plaques that were classified by conventional angioscopy, was respectively 26, 44 and 94, indicating significantly (p<0.05) higher incidence in the latter than the former two groups. Distribution pattern was classified as patchy, diffuse and web-like. Web-like pattern was observed only in yellow plaques with necrotic core. (2) By transected surface scan, oxLDL deposited within superficial layer in normal segments and diffusely within both superficial and deep layers in white and yellow plaques. In yellow plaques with necrotic core, oxLDL deposited not only in the marginal zone of the necrotic core but also in the fibrous cap.Conclusion
Taken into consideration of the well-known process of coronary plaque growth, the results suggest that oxLDL begins to deposit in human coronary artery wall before plaque formation and increasingly deposits with plaque growth, exhibiting different deposition sites and patterns depending on morphological changes. 相似文献958.
Yusuke Murata Kyoji Nishio Takayuki Mochiyama Morichika Konishi Masaya Shimada Hiroya Ohta Nobuyuki Itoh 《PloS one》2013,8(7)
Background
A low-carbohydrate, high-fat ketogenic diet (KD) induces hepatic ketogenesis and is believed to affect energy metabolism in mice. As hepatic Fgf21 expression was markedly induced in mice fed KD, we examined the effects of KD feeding on metabolism and the roles of Fgf21 in metabolism in mice fed KD using Fgf21 knockout mice.Methodology/Principal Findings
We examined C57BL/6 mice fed KD for 6 or 14 days. Blood β-hydroxybutyrate levels were greatly increased at 6 days, indicating that hepatic ketogenesis was induced effectively by KD feeding for 6 days. KD feeding for 6 and 14 days impaired glucose tolerance and insulin sensitivity, although it did not affect body weight, blood NEFA, and triglyceride levels. Hepatic Fgf21 expression and blood Fgf21 levels were markedly increased in mice fed KD for 6 days. Blood β-hydroxybutyrate levels in the knockout mice fed KD for 6 days were comparable to those in wild-type mice fed KD, indicating that Fgf21 is not required for ketogenesis. However, the impaired glucose tolerance and insulin sensitivity caused by KD feeding were improved in the knockout mice. Insulin-stimulated Akt phosphorylation was significantly decreased in the white adipose tissue in wild-type mice fed KD compared with those fed normal chow, but not in the muscle and liver. Its phosphorylation in the white adipose tissue was significantly increased in the knockout mice fed KD compared with wild-type mice fed KD. In contrast, hepatic gluconeogenic gene expression in Fgf21 knockout mice fed KD was comparable to those in the wild-type mice fed KD.Conclusions/Significance
The present findings indicate that KD feeding impairs insulin sensitivity in mice due to insulin resistance in white adipose tissue. In addition, our findings indicate that Fgf21 induced to express by KD is a negative regulator of adipocyte insulin sensitivity in adaptation to a low-carbohydrate malnutritional state. 相似文献959.
Hiroyuki Endo Takeharu Shiroki Takayuki Nakagawa Misa Yokoyama Keiichi Tamai Hideaki Yamanami Tsuneaki Fujiya Ikuro Sato Kazunori Yamaguchi Nobuyuki Tanaka Katsunori Iijima Tooru Shimosegawa Kazuo Sugamura Kennichi Satoh 《PloS one》2013,8(10)
The long non-coding RNA HOTAIR has been reported to be a poor prognostic biomarker in a variety of malignant tumors. However, little is known about the association of HOTAIR with gastric cancer. We examined the expression of HOTAIR in 68 gastric cancer samples using quantitative real-time RT-PCR and analyzed its correlation with the clinical parameters. The functional role of HOTAIR was examined by generating human gastric cancer cell lines with increased or suppressed HOTAIR expression. The anchorage -independent growth was assessed by soft agar assay. The increased or suppressed HOTAIR expressing gastric cancer cells were injected into the tail vein or peritoneal cavity of immunodeficient mice to examine the effect of this molecule on metastasis and peritoneal dissemination. The expression of HOTAIR was significantly higher in cancer lesions than in adjacent non-cancerous tissues in human gastric cancers. In the diffuse type of gastric cancer, the High-HOTAIR group (HOTAIR/GAPDH > 1) showed significantly more venous invasion, frequent lymph node metastases and a lower overall survival rate compared to the Low-HOTAIR group (HOTAIR/GAPDH < 1). Colony formation on the soft agar was enhanced in a HOTAIR-dependent manner. HOTAIR-expressing MKN74 formed more liver metastasis compared to control when they were injected into the tail vein of mice. In addition, reduced expression of HOTAIR in KATO III suppressed peritoneal dissemination. These results suggest that HOTAIR plays a pivotal role in the development of gastric cancer. 相似文献
960.
Akihiko Nakamura Hideshi Niimura Kazuyo Kuwabara Toshiro Takezaki Emi Morita Kenji Wakai Nobuyuki Hamajima Yuichiro Nishida Tanvir Chowdhury Turin Sadao Suzuki Keizo Ohnaka Hirokazu Uemura Etsuko Ozaki Satoyo Hosono Haruo Mikami Michiaki Kubo Hideo Tanaka 《PloS one》2013,8(12)