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51.
Yuko Kimura Noboru Takamura Masato Fukunaga Mitsuo Kanagae Yasuyo Abe Kiyoshi Aoyagi 《Biomarkers》2013,18(3):291-297
Primary objective: To carry out a preliminary evaluation of subclinical inflammation and its genetic background in young adults.Research design: Fifty-five healthy Japanese young adults aged 19–27 years (37 males and 18 females, mean age: 22.3 years), and 58 healthy Japanese adults aged 40 to 60 years (21 males and 37 females, mean age: 51.5 years) were included in this study.Methods and procedures: We measured plasma high-sensitive C-reactive protein (hs-CRP) levels and screened for the C677T polymorphism of the 5-10 methylenetetrahydrofolate reductase gene (MTHFR), which is considered a genetic risk factor for atherosclerosis, by HinfI digestion.Main outcomes and results: Hs-CRP levels of the young adult group were significantly lower than the levels of the middle aged group (0.014±0.030 mg/dl vs. 0.031±0.040 mg/dl, p=0.005). The levels were significantly higher in males than in females (0.028±0.019 mg/dl vs. 0.013±0.010 mg/dl, p=0.008) among young adults. Furthermore, we evaluated the relationship of the C677T genotype and hs-CRP values, but found no association between them.Conclusions: Although the sample size is limited, our preliminary study demonstrated the profiles of hs-CRP in Japanese young adults. Further investigation will be needed to establish the guidelines for customized school health education using sensitive laboratory and genetic markers. 相似文献
52.
Amina Sugimoto Shuhei Nomura Masaharu Tsubokura Tomoko Matsumura Kaori Muto Mikiko Sato Stuart Gilmour 《PloS one》2013,8(8)
Background
The Fukushima Daiichi nuclear disaster caused a global panic by a release of harmful radionuclides. In a disaster setting, misusage of contemporary media sources available today can lead to disseminated incorrect information and panic. The study aims to build a scale which examines associations between media and individual anxieties, and to propose effective media usages for future disaster management.Methods
The University of Tokyo collaborated with the Fukushima local government to conduct a radiation-health-seminar for a total of 1560 residents, at 12 different locations in Fukushima. A 13 item questionnaire collected once before and after a radiation-seminar was used on factor analysis to develop sub-scales for multiple regression models, to determine relationships between the sub-scales and media type consumed. A paired t–test was used to examine any changes in sub-scale of pre- and post-seminar scores.Results
Three sub-scales were revealed and were associated with different media types: was with rumors, while concern for the future was positively associated with regional-newspapers and negatively with national-newspapers. Anxiety about social-disruption was associated with radio. The seminar had a significant effect on anxiety reduction for all the three sub-scales.Conclusion
Different media types were associated with various heightened concerns, and that a radiation seminar was helpful to reduce anxieties in the post-disaster setting. By tailoring post-disaster messages via specific media types, i.e., radio, it may be possible to effectively convey important information, as well as to calm fears about particular elements of post-disaster recovery and to combat rumors. 相似文献53.
Kiyoshi Migita Toru Arai Naoki Ishizuka Yuka Jiuchi Yasuharu Sasaki Yasumori Izumi Tetsuyuki Kiyokawa Eiichi Suematsu Tomoya Miyamura Hiroshi Tsutani Yojiro Kawabe Ryutaro Matsumura Shunsuke Mori Shiro Ohshima Shigeru Yoshizawa Kenji Kawakami Yasuo Suenaga Hideo Nishimura Toyohiko Sugimoto Hiroaki Iwase Hideyuki Sawada Haruhiro Yamashita Shigeyuki Kuratsu Fumitaka Ogushi Masaharu Kawabata Toshihiro Matsui Hiroshi Furukawa Seiji Bito Shigeto Tohma 《PloS one》2013,8(11)
Background/Aims
The Japanese National Hospital Organization evidence-based medicine (EBM) Study group for Adverse effects of Corticosteroid therapy (J-NHOSAC) is a Japanese hospital-based cohort study investigating the safety of the initial use of glucocorticoids (GCs) in patients with newly diagnosed autoimmune diseases. Using the J-NHOSAC registry, the purpose of this observational study is to analyse the rates, characteristics and associated risk factors of intracellular infections in patients with newly diagnosed autoimmune diseases who were initially treated with GCs.Methodology/Principal Findings
A total 604 patients with newly diagnosed autoimmune diseases treated with GCs were enrolled in this registry between April 2007 and March 2009. Cox proportional-hazards regression was used to determine independent risk factors for serious intracellular infections with covariates including sex, age, co-morbidity, laboratory data, use of immunosuppressants and dose of GCs. Survival was analysed according to the Kaplan-Meier method and was assessed by the log-rank test. There were 127 serious infections, including 43 intracellular infections, during 1105.8 patient-years of follow-up. The 43 serious intracellular infections resulted in 8 deaths. After adjustment for covariates, diabetes (Odds ratio [OR]: 2.5, 95% confidence interval [95% CI] 1.1–5.9), lymphocytopenia (≦1000/μl, OR: 2.5, 95% CI 1.2–5.2) and use of high-dose (≧30 mg/day) GCs (OR: 2.4, 95% CI 1.1–5.3) increased the risk of intracellular infections. Survival curves showed lower intracellular infection-free survival rate in patients with diabetes, lymphocytopaenia and high-dose GCs treatments.Conclusions/Significance
Patients with newly diagnosed autoimmune diseases were at high risk of developing intracellular infection during initial treatment with GCs. Our findings provide background data on the risk of intracellular infections of patients with autoimmune diseases. Clinicians showed remain vigilant for intracellular infections in patients with autoimmune diseases who are treated with GCs. 相似文献54.
55.
Hideaki Tagashira Chen Zhang Ying-mei Lu Hideyuki Hasegawa Hiroshi Kanai Feng Han Kohji Fukunaga 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
We previously reported that the σ1-receptor (σ1R) is down-regulated following cardiac hypertrophy and dysfunction in transverse aortic constriction (TAC) mice. Here we address how σ1R stimulation with the selective σ1R agonist SA4503 restores hypertrophy-induced cardiac dysfunction through σ1R localized in the sarcoplasmic reticulum (SR).Methods
We first confirmed anti-hypertrophic effects of SA4503 (0.1–1 μM) in cultured cardiomyocytes exposed to angiotensin II (Ang II). Then, to confirm the ameliorative effects of σ1R stimulation in vivo, we administered SA4503 (1.0 mg/kg) and the σ1R antagonist NE-100 (1.0 mg/kg) orally to TAC mice for 4 weeks (once daily).Results
σ1R stimulation with SA4503 significantly inhibited Ang II-induced cardiomyocyte hypertrophy. Ang II exposure for 72 h impaired phenylephrine (PE)-induced Ca2 + mobilization from the SR into both the cytosol and mitochondria. Treatment of cardiomyocytes with SA4503 largely restored PE-induced Ca2 + mobilization into mitochondria. Exposure of cardiomyocytes to Ang II for 72 h decreased basal ATP content and PE-induced ATP production concomitant with reduced mitochondrial size, while SA4503 treatment completely restored ATP production and mitochondrial size. Pretreatment with NE-100 or siRNA abolished these effects. Chronic SA4503 administration also significantly attenuated myocardial hypertrophy and restored ATP production in TAC mice. SA4503 administration also decreased hypertrophy-induced impairments in LV contractile function.Conclusions
σ1R stimulation with the specific agonist SA4503 ameliorates cardiac hypertrophy and dysfunction by restoring both mitochondrial Ca2 + mobilization and ATP production via σ1R stimulation.General significance
Our observations suggest that σ1R stimulation represents a new therapeutic strategy to rescue the heart from hypertrophic dysfunction. 相似文献56.
Kazuhiro Shiozaki Kazuki Takeshita Mako Ikeda Asami Ikeda Yusuke Harasaki Masaharu Komatsu Shoji Yamada Kazunori Yamaguchi Taeko Miyagi 《Biochimie》2013
Mammalian Neu3 sialidases are involved in various biological processes, such as cell death and differentiation, through desialylation of gangliosides. The enzymatic profile of Neu3 seems to be highly conserved from birds to mammals. In fish, the functional properties of Neu3 sialidase are not clearly understood, with the partial exception of the zebrafish form. To cast further light on the molecular evolution of Neu3 sialidase, we identified the encoding genes in the medaka Oryzias latipes and investigated the properties of the enzyme. PCR amplification using medaka brain cDNA allowed identification of two novel medaka Neu3 genes, neu3a and neu3b. The YRIP, VGPG motif and Asp-Box, characteristic of consensus motifs of sialidases, were well conserved in the both medaka Neu3 sialidases. When each gene was transfected into HEK293 to allow cell lysates for the use of enzymatic characterization, two Neu3 sialidases showed strict substrate specificity toward gangliosides, similar to mammalian Neu3. The optimal pH values were at pH 4.2 and pH 4.0, respectively, and neu3b in particular showed a broad optimum. Immunofluorescence assays indicated neu3a localization at plasma membranes, while neu3b was found in cytosol. The tissue distribution of two genes was then investigated by estimation of mRNA expression and sialidase activity, both being dominantly expressed in the brain. In neu3a gene-transfected neuroblastoma cells, the enzyme was found to positively regulate retinoic acid-induced differentiation with the elongation of axon length. On the other hand, neu3b did not affect neurite formation. These results and phylogenetic analysis suggested that the medaka neu3a is an evolutionally conserved sialidase with regard to enzymatic properties, whereas neu3b is likely to have originally evolved in medaka. 相似文献
57.
58.
Wei Zou Monica Croke Tomohiro Fukunaga Thomas J. Broekelmann Robert P. Mecham Steven L. Teitelbaum 《Journal of cellular biochemistry》2013,114(8):1871-1878
The αvβ3 integrin stimulates the resorptive capacity of the differentiated osteoclast (OC) by organizing its cytoskeleton via the tyrosine kinase, Syk. Thus, Syk‐deficient OCs fails to spread or form actin rings, in vitro and in vivo. The Syk family of tyrosine kinases consists of Syk itself and Zap70 which are expressed by different cell types. Because of their structural similarity, and its compensatory properties in other cells, we asked if Zap70 can substitute for absence of Syk in OCs. While expression of Syk, as expected, normalizes the cytoskeletal abnormalities of Syk?/? OCs, Zap70 fails do so. In keeping with this observation, Syk, but not Zap70, rescues αvβ3 integrin‐induced SLP76 phosphorylation in Syk?/? OCs. Furthermore the kinase sequence of Syk partially rescues the Syk?/? phenotype but full normalization also requires its SH2 domains. Surprisingly, expression of Zap70 inhibits WT OC spreading, actin ring formation and bone resorptive activity, but not differentiation. In keeping with arrested cytoskeletal organization, Zap70 blocks integrin‐activated endogenous Syk and Vav3, SLP76 phosphorylation. Such inhibition requires Zap70 kinase activity, as it is abolished by mutation of the Zap70 kinase domain. Thus, while the kinase domain of Syk is uniquely required for OC function that of Zap70 inhibits it. J. Cell. Biochem. 114: 1871–1878, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
59.
Fumiaki Nakayama Sachiko Umeda Tomomi Ichimiya Shin Kamiyama Masaharu Hazawa Takeshi Yasuda Shoko Nishihara Takashi Imai 《FEBS letters》2013,587(2):231-237
This study focuses on clarifying the contribution of sulfation to radiation-induced apoptosis in human Burkitt’s lymphoma cell lines, using 3′-phosphoadenosine 5′-phosphosulfate transporters (PAPSTs). Overexpression of PAPST1 or PAPST2 reduced radiation-induced apoptosis in Namalwa cells, whereas the repression of PAPST1 expression enhanced apoptosis. Inhibition of PAPST slightly decreased keratan sulfate (KS) expression, so that depletion of KS significantly increased radiation-induced apoptosis. In addition, the repression of all three N-acetylglucosamine-6-O-sulfotransferases (CHST2, CHST6, and CHST7) increased apoptosis. In contrast, PAPST1 expression promoted the phosphorylation of p38 MAPK and Akt in irradiated Namalwa cells. These findings suggest that 6-O-sulfation of GlcNAc residues in KS reduces radiation-induced apoptosis of human Burkitt’s lymphoma cells. 相似文献
60.
Salinization of crop fields is a pressing matter for sustainable agriculture under desertification and is largely attributed to root absorptive functions of the major crops such as maize. The rates of water and ion absorption of intact root system of maize plants were measured under the salinized condition, and the salt absorptive function of maize roots was analyzed by applying different two kinetic models of root ion absorption (i.e. the concentration dependent model and the transpiration integrated model). The absorption rates for salinization ions (Na+, Cl?, Ca2+ and Mg2+) were found to depend on ion mass flow through roots driven by the transpiration, and therefore the transpiration integrated model represented more accurately rates of root ion absorption. The root absorption of salinization ions was characterized quantitatively by two model parameters of Q′max and K′M involved in the transpiration integrated model, which are considered to relate to the potential absorbing power and the ion affinity of transport proteins on root cell membranes, respectively. 相似文献