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51.
Masanao Matsui Kenji Mori Yoichi Ozawa 《Bioscience, biotechnology, and biochemistry》2013,77(2):193-195
A synthesis of oospolactone (3,4-dimethyl-8-hydroxyisocoumarin), a metabolite of Oospora astringenes, is described. 相似文献
52.
Kazunori Sasaki Tomoyuki Oki Yumi Kai Yoichi Nishiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):1308-1314
The purpose of this study was to investigate the effect of repeated harvesting on the content of caffeic acid (CA) and seven species of caffeoylquinic acids (CQAs) in sweet potato leaves using a newly developed high-performance liquid chromatography method. Six cultivars and two breeding lines were used in this study. Leaves were collected at monthly intervals from 1st harvest (May) to 4th harvest (August) in 2011 and 2012. ANOVA analysis revealed that the contents of CQAs were significantly different among all cultivars and breeding lines, but no significant differences were found for CA. No annual variation was confirmed in CA and CQAs. Repeated harvest of sweet potato leaves affected the content of only 4-CQA and 5-CQA. Post-hoc comparisons using Tukey’s method indicated that the contents of 4-CQA and 5-CQA in sweet potato leaves harvested at first time were significantly higher compared to those at the other harvest times. 相似文献
53.
Yoichi Ozawa Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(10):2373-2378
Sixteen new Cecropia juvenile hormone (JH) analogs with different alkyl substituents at C–7 and C–11 were synthesized as stereoisomeric mixtures. The epoxides with n-propyl or n-butyl and methyl groups at C-11 and methyl or ethyl group at C-7 showed high JH activity on Bombyx mori L. Structure-activity relationship of the JH analogs was discussed. 相似文献
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Kazuaki Yamanaka Yoichi Kakuta Shuji Miyagawa Shigeaki Nakazawa Taigo Kato Toyofumi Abe Ryoichi Imamura Masayoshi Okumi Akira Maeda Hiroomi Okuyama Masashi Mizuno Norio Nonomura 《PloS one》2016,11(2)
Background
The association of complement with the progression of acute T cell mediated rejection (ATCMR) is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs) in acute T-cell mediated rejection using rat and human renal allografts.Methods
We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR) and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP) by immunohistochemical staining in human renal grafts and their clinical course.Results
qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry), was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate.Conclusions
We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR. 相似文献56.
Taku Watanabe Ichizo Tsujino Satoshi Konno Yoichi M. Ito Chisa Takashina Takahiro Sato Akira Isada Hiroshi Ohira Yoshinori Ohtsuka Yuma Fukutomi Hiroyuki Nakamura Yukio Kawagishi Chiharu Okada Nobuyuki Hizawa Masami Taniguchi Akira Akasawa Masaharu Nishimura 《PloS one》2016,11(3)
Objective
A positive association between the number of cigarettes smoked per day and obesity has been reported, whereas how other smoking-related indices, such as pack-years and duration of smoking, are related with obesity has been less investigated. We analyzed the age-adjusted cross-sectional association between smoking and obesity in a general Japanese population.Methods
We used data from a nationwide epidemiological study of Japanese adults (N = 23,106). We compared the prevalence of obesity (defined as body mass index ≥ 25kg/m2) among groups classified by smoking behavior, pack-years, number of cigarettes per day, duration of smoking, and duration and time of smoking cessation.Results
In men, current smokers had a lower odds ratio (OR) for obesity of 0.80 (95% confidence interval (CI): 0.72–0.88) compared to non-smokers, whereas past smokers had a higher OR of 1.23 (95% CI: 1.09–1.37) compared to current smokers. In women, there were no differences in obesity between the three groups classified by smoking behavior. However, in both sexes, the prevalence of obesity tended to increase with pack-years and the number of cigarettes per day, but not with duration of smoking in current and past smokers. Further, in male smokers, the risks for obesity were markedly higher in short-term heavy smokers compared with long-term light smokers, even with the same number of pack-years. Regarding the impact of smoking cessation, female past smokers who quit smoking at an age > 55-years had an elevated OR of 1.60 (95% CI:1.05–2.38) for obesity.Conclusions
In a general Japanese population, obesity is progressively associated with pack-years and number of cigarettes per day, but not with the duration of smoking. When investigating the association between obesity and cigarette smoking, the daily smoking burden and the duration of smoking require to be independently considered. 相似文献57.
Takehide Kimura Hideyuki Kuwata Kazuhito Miyauchi Yuki Katayama Norihiko Kayahara Hiroyuki Sugiuchi Kazumi Matsushima Yuki Kondo Yoichi Ishitsuka Mitsuru Irikura Tetsumi Irie 《Analytical biochemistry》2016
Serum sphingomyelin (SM) has predictive value in the development of atherosclerosis. Furthermore, SM plays important roles in cell membrane structure, signal transduction pathways, and lipid raft formation. A convenient enzymatic method for SM is available for routine laboratory practice, but the enzyme specificity is not sufficient because of nonspecific reactions with lysophosphatidylcholine (LPC). Based on the differential specificity of selected enzymes toward choline-containing phospholipids, a two-step assay for measuring SM was constructed and its performance was evaluated using sera from healthy individuals on a Hitachi 7170 autoanalyzer. Results from this assay were highly correlated with theoretical serum SM concentrations estimated by subtracting phosphatidylcholine (PC) and LPC concentrations from that of total phospholipids determined using previously established methods. There was a good correlation between the results of SM assayed by the proposed method and the existing enzymatic method in sera from healthy individuals. Moreover, the proposed method was superior to the existing method in preventing nonspecific reactions with LPC present in sera. The proposed method does not require any pretreatment, uses 2.5 μl of serum samples, and requires only 10 min on an autoanalyzer. This high-throughput method can measure serum SM with sufficient specificity for clinical purposes and is applicable in routine laboratory practice. 相似文献
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Ono N Nakashima K Schipani E Hayata T Ezura Y Soma K Kronenberg HM Noda M 《The Journal of biological chemistry》2007,282(35):25509-25516
Multiple signaling pathways participate in the regulation of bone remodeling, and pathological negative balance in the regulation results in osteoporosis. However, interactions of signaling pathways that act comprehensively in concert to maintain bone mass are not fully understood. We investigated roles of parathyroid hormone receptor (PTH/PTHrP receptor) signaling in osteoblasts in unloading-induced bone loss using transgenic mice. Hind limb unloading by tail suspension reduced bone mass in wild-type mice. In contrast, signaling by constitutively active PTH/PTHrP receptor (caPPR), whose expression was regulated by the osteoblast-specific Col1a1 promoter (Col1a1-caPPR), suppressed unloading-induced reduction in bone mass in these transgenic mice. In Col1a1-caPPR transgenic (Tg) mice, hind limb unloading suppressed bone formation parameters in vivo and mineralized nodule formation in vitro similarly to those observed in wild-type mice. In addition, serum osteocalcin levels and mRNA expression levels of type I collagen, Runx2 and Osterix in bone were suppressed by unloading in both wild-type mice and Tg mice. However, in contrast to unloading-induced enhancement of bone resorption parameters in wild-type mice, Col1a1-caPPR signaling suppressed, rather than enhanced, osteoclast number and osteoclast surface as well as urinary deoxypyridinoline excretion upon unloading. Col1a1-caPPR signaling also suppressed mRNA expression levels of RANK and c-fms in bone upon unloading. Although the M-CSF and monocyte chemoattractant protein 1 (MCP-1) mRNA levels were enhanced in control Tg mice, these levels were suppressed in unloaded Tg mice. These results indicated that constitutive activation of PTH/PTHrP receptor signaling in osteoblastic cells suppresses unloading-induced bone loss specifically through the regulation of osteoclastic activity. 相似文献