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831.
832.
Kouji Sakai Tomoki Yoshikawa Fumio Seki Shuetsu Fukushi Maino Tahara Noriyo Nagata Yasushi Ami Tetsuya Mizutani Ichiro Kurane Ryoji Yamaguchi Hideki Hasegawa Masayuki Saijo Katsuhiro Komase Shigeru Morikawa Makoto Takeda 《Journal of virology》2013,87(12):7170-7175
A canine distemper virus (CDV) strain, CYN07-dV, associated with a lethal outbreak in monkeys, used human signaling lymphocyte activation molecule as a receptor only poorly but readily adapted to use it following a P541S substitution in the hemagglutinin protein. Since CYN07-dV had an intrinsic ability to use human nectin-4, the adapted virus became able to use both human immune and epithelial cell receptors, as well as monkey and canine ones, suggesting that CDV can potentially infect humans. 相似文献
833.
Atsumu Abe Soichi Furukawa Yuya Migita Motoharu Tanaka Hirokazu Ogihara Yasushi Morinaga 《Current microbiology》2013,66(5):515-521
We studied morphologic changes after sublethal high hydrostatic pressure treatment (HPT) of Escherichia coli K-12 strains in which genes related to the cytoskeleton, cell wall, and cell division had been deleted. Some long filamentous and swelling cells were observed in wild-type bacteria, while some spherical, branched, or collapsed cells were observed in deletion mutants. In particular, ΔzapA and ΔrodZ showed distinguished morphologies. ZapA supports FtsZ, a cytoskeletal protein, forming ring with ZapB. RodZ, a cytoskeletal protein, interacts with MreB, also a cytoskeletal protein, and both factors are necessary for maintaining the rod shape of the cell. These results showed that insufficient formation of FtsZ rings induced cell elongation and that insufficient formation of MreB induced a branched and collapsed cell shape. Therefore, the correct formation of the bacteria cytoskeleton by FtsZ rings and MreB is important for keeping normal cell shape during growth after HPT, and the polymerization of cytoskeletal proteins was a critical target of sublethal HPT. These results indicate that sublethal HPT induces bacterial cell morphologic change and provide important information on the role of genes involved in morphogenesis. Therefore, sublethal HPT may be a good tool for studying the morphogenesis of bacterial cells. 相似文献
834.
Miyako Takata Shigehiro Ohdo Yasushi Fukuoka Masanori Miyata Masahiro Endo 《Chronobiology international》2013,30(4):777-783
The mammalian Per1 gene is one of the most important components of circadian clock function of the suprachiasmatic nucleus and peripheral tissues. We examined whether the β2‐adrenoceptor agonists, procaterol and fenoterol, induce human Per1 mRNA expression in human bronchial epithelium. The in vitro stimulation of β2‐adrenoceptor agonists in BEAS‐2B cells led to a remarkable increase in the level of hPer1 mRNA. Moreover, fenoterol or procaterol induced the phosphorylation of CREB in BEAS‐2B cells as verified by immunoblot analysis. β2‐adrenoceptor agonists induced human Per1 mRNA expression by the signaling pathways of cAMP‐CREB in BEAS‐2B cells. 相似文献
835.
Yasushi Suwazono Mirei Dochi Mitsuhiro Oishi Kumihiko Tanaka Etsuko Kobayashi Kouichi Sakata 《Chronobiology international》2013,30(5):926-941
The aim of this study was to assess the effect of shiftwork on hemoglobin A1c (HbA1c) level, as an index of glucose metabolism. A 14 yr prospective cohort study was conducted on day (n?=?4219) and alternating shiftworkers (n?=?2885) who received annual health checkups between 1991 and 2005 at a Japanese steel company. The endpoints were either a 10%, 15%, 20%, 25%, or 30% increase in HbA1c during the period of observation, compared to HbA1c at entry to the study. The association between the type of job schedule and increase in HbA1c was investigated after adjusting for age, body mass index, mean arterial pressure, total serum cholesterol, creatinine, alanine aminotransferase, γ-glutamyl transpeptidase, uric acid, drinking habit, smoking habit, and habitual exercise using multivariate pooled logistic regression analyses. Shiftwork was significantly associated with the various HbA1c endpoints (≥10% HbA1c increase, odds ratio 1.35 [95% confidence interval 1.26–1.44]; ≥15% HbA1c increase, odds ratio 1.29 [95% confidence interval, 1.19–1.40]; ≥20% HbA1c increase, odds ratio 1.23 [95% confidence interval 1.11–1.37]; and ≥25% HbA1c increase, odds ratio 1.19 [95% confidence interval 1.03–1.36]). Age, body mass index, alanine aminotransferase, and γ-glutamyl transpeptidase were associated positively with all five HbA1c endpoints. Uric acid was associated negatively with all five HbA1c endpoints. Our study on male Japanese workers revealed alternating shiftwork (in addition to other established factors, such as age and body mass index) was a consistent risk factor for impaired glucose metabolism. 相似文献
836.
Yasushi Kishimoto Moritoshi Hirono Ryuichiro Atarashi Suehiro Sakaguchi Tohru Yoshioka Shigeru Katamine Yutaka Kirino 《PloS one》2013,8(4)
Mice lacking the prion protein (PrPC) gene (Prnp), Ngsk Prnp
0/0 mice, show late-onset cerebellar Purkinje cell (PC) degeneration because of ectopic overexpression of PrPC-like protein (PrPLP/Dpl). Because PrPC is highly expressed in cerebellar neurons (including PCs and granule cells), it may be involved in cerebellar synaptic function and cerebellar cognitive function. However, no studies have been conducted to investigate the possible involvement of PrPC and/or PrPLP/Dpl in cerebellum-dependent discrete motor learning. Therefore, the present cross-sectional study was designed to examine cerebellum-dependent delay eyeblink conditioning in Ngsk Prnp
0/0 mice in adulthood (16, 40, and 60 weeks of age). The aims of the present study were two-fold: (1) to examine the role of PrPC and/or PrPLP/Dpl in cerebellum-dependent motor learning and (2) to confirm the age-related deterioration of eyeblink conditioning in Ngsk Prnp
0/0 mice as an animal model of progressive cerebellar degeneration. Ngsk Prnp
0/0 mice aged 16 weeks exhibited intact acquisition of conditioned eyeblink responses (CRs), although the CR timing was altered. The same result was observed in another line of PrPc-deficient mice, ZrchI PrnP
0/0 mice. However, at 40 weeks of age, CR incidence impairment was observed in Ngsk Prnp
0/0 mice. Furthermore, Ngsk Prnp
0/0 mice aged 60 weeks showed more significantly impaired CR acquisition than Ngsk Prnp
0/0 mice aged 40 weeks, indicating the temporal correlation between cerebellar PC degeneration and motor learning deficits. Our findings indicate the importance of the cerebellar cortex in delay eyeblink conditioning and suggest an important physiological role of prion protein in cerebellar motor learning. 相似文献
837.
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838.
Eisaburo Sueoka Naoko Sueoka-Aragane Akemi Sato Masaru Ide Hideaki Nakamura Yusuke Sotomaru Choji Taya Hiromichi Yonekawa Tomoyuki Kitagawa Yasushi Kubota Shinya Kimura Kei Nakachi Keiji Tanimoto 《PloS one》2013,8(4)
Hypoxia-inducible factor-1alpha (HIF-1 alpha) plays an essential role in the regulation of various genes associated with low oxygen consumption. Elevated expression of HIF-1alpha has been reported to be associated with tumor progression, invasion and metastasis in many cancers. To investigate the role of HIF-1alpha in tumor development and metastasis, we established transgenic mice constitutively expressing HIF1A gene under regulation of the cytomegalovirus gene promoter. Although HIF-1alpha protein levels varied among organs, expression of HIF1A mRNA in most organs gradually increased in an age-dependent manner. The transgenic mice showed no gross morphological abnormality up to 8 weeks after birth, although they subsequently developed tumors in the lymphoid, lung, and breast; the most prominent tumor was lymphoma appearing in the intestinal mucosa and intra-mesenchymal tissues. The prevalence of tumors reached 80% in 13 months after birth. The constitution of lymphocyte populations in the transgenic mice did not differ from that in wild-type mice. However, lymphocytes of the transgenic mice revealed prolonged survival under long-term culture conditions and revealed increased resistance to cytotoxic etoposide. These results suggest that HIF-1alpha itself is not oncogenic but it may play an important role in lymphomagenesis mediated through the prolonged survival of lymphocytes in this transgenic mouse model. 相似文献
839.
Munetaka Iwata Hiroki Ochi Yasushi Hara Masahiro Tagawa Daisuke Koga Atsushi Okawa Yoshinori Asou 《PloS one》2013,8(4)
Obesity and high body mass index are associated with a higher incidence of osteoarthritis (OA). The aim of this study is to investigate the involvement of the infrapatellar fat pad (IPFP) in the sub-acute effect of a high fat diet (HFD) on the development of knee-OA. C57BL/6J male mice were fed either a HFD or a normal diet beginning at seven weeks of age. Tissue sections were evaluated with immunohistological analysis. The IPFP was excised, and mRNA expression profiles were compared using real-time RT-PCR analysis. Osteoarthritic changes were initiated in the HFD group after eight weeks of the HFD. Increased synovial cell number and angiogenesis at the anterior edge of the tibial plateau were exhibited prior to osteophyte formation. Quantitative histological analysis indicated that osteophyte volume was significantly increased in the HFD group after eight weeks, along with an increase in the IPFP volume, the size of individual adipocytes and the number of vessels in the IPFP. Histomorphometrical analysis revealed osteophyte area was significantly associated with IPFP area, individual adipocyte area and vascular area. Real-time RT-PCR analysis demonstrated elevated mRNA expression of inflammatory cytokines, growth factor, and adipokines in the IPFP after eight weeks of the HFD. These findings are in parallel with increased expression of the CD68 macrophage marker after eight weeks of the HFD. Expression levels of the adipokines were significantly correlated with expression of TNF-α, VEGF and TGF-β. Immunohistological analysis revealed that the Nampt protein was highly expressed in the IPFP especially around the site of osteophyte formation. Apoptosis and proliferation of chondrocytes were both enhanced at the site of osteophyte formation, indicating higher cell turnover at this region. These observations suggest the IPFP plays a pivotal role in the formation of osteophytes and functions as a secretory organ in response to a HFD. 相似文献
840.
Relationships among Smoking Habits,Airflow Limitations,and Metabolic Abnormalities in School Workers
Masafumi Horie Satoshi Noguchi Wakae Tanaka Yasushi Goto Hisanao Yoshihara Masaki Kawakami Masaru Suzuki Yoshio Sakamoto 《PloS one》2013,8(11)