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161.
Hiroshi Shiragami Yusuke Amino Yutaka Honda Masayuki Arai Yasuhiro Tanaka Hisao Iwagami 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):31-45
Abstract Practical method to produce 2′,3′-dideoxypurinenucleosides from 9-(2,5-di-O-acetyl-3-bromo-3-deoxy-β-D-xylofuranosyl)purines (1) was developed. High ratio of 2′,3′-dideoxynucleoside to 3′-deoxyribonucleoside was obtained by selecting the reaction conditions (solvent, pH and/or base), or changing 2′-acyloxy leaving group. The reaction mechanism was studied by deuteration experiments of 1a and 1-(3,5-di-O-acety1-2-bromo-2-deoxy-β-D-ribofuranosyl)thymine (12). 相似文献
162.
Yoshikazu Arai Jun Ohgane Shuh‐hei Fujishiro Kazuaki Nakano Hitomi Matsunari Masahito Watanabe Kazuhiro Umeyama Dai Azuma Naomi Uchida Nozomu Sakamoto Tomohiro Makino Shintaro Yagi Kunio Shiota Yutaka Hanazono Hiroshi Nagashima 《Genesis (New York, N.Y. : 2000)》2013,51(11):763-776
Porcine induced pluripotent stem cells (iPSCs) provide useful information for translational research. The quality of iPSCs can be assessed by their ability to differentiate into various cell types after chimera formation. However, analysis of chimera formation in pigs is a labor‐intensive and costly process, necessitating a simple evaluation method for porcine iPSCs. Our previous study identified mouse embryonic stem cell (ESC)‐specific hypomethylated loci (EShypo‐T‐DMRs), and, in this study, 36 genes selected from these were used to evaluate porcine iPSC lines. Based on the methylation profiles of the 36 genes, the iPSC line, Porco Rosso‐4, was found closest to mouse pluripotent stem cells among 5 porcine iPSCs. Moreover, Porco Rosso‐4 more efficiently contributed to the inner cell mass (ICM) of blastocysts than the iPSC line showing the lowest reprogramming of the 36 genes (Porco Rosso‐622‐14), indicating that the DNA methylation profile correlates with efficiency of ICM contribution. Furthermore, factors known to enhance iPSC quality (serum‐free medium with PD0325901 and CHIR99021) improved the methylation status at the 36 genes. Thus, the DNA methylation profile of these 36 genes is a viable index for evaluation of porcine iPSCs. genesis 51:763–776. © 2013 Wiley Periodicals, Inc. 相似文献
163.
164.
Jun Kojima Jun Araya Hiromichi Hara Saburo Ito Naoki Takasaka Kenji Kobayashi Satoko Fujii Chikako Tsurushige Takanori Numata Takeo Ishikawa Kenichiro Shimizu Makoto Kawaishi Keisuke Saito Noriki Kamiya Jun Hirano Makoto Odaka Toshiaki Morikawa Hiroshi Hano Satoko Arai Toru Miyazaki Yumi Kaneko Katsutoshi Nakayama Kazuyoshi Kuwano 《Respiratory research》2013,14(1):30
Background
Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure.Methods
Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM.Results
The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure.Conclusions
These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD. 相似文献165.
Yumeko Hayashi Yoshiki Ishii Mitsumi Hata-Suzuki Ryo Arai Kazuyuki Chibana Akihiro Takemasa Takeshi Fukuda 《Respiratory research》2013,14(1):29
Background
Dendritic cells (DCs) are professional antigen-presenting cells that play a crucial role in the initiation and modulation of immune responses. Human circulating blood DCs are divided into two major subsets: myeloid DCs (mDCs); and plasmacytoid DCs (pDCs). Furthermore, mDCs are subdivided into two subsets: Th1-promoting mDCs (mDC1s); and Th2-promoting mDCs (mDC2s). Although CD1a, CD1c, and CD141 are generally used for classifying mDC subsets, their adequacy as a specific marker remains unclear. We performed this study to compare circulating mDC, pDC, mDC1, and mDC2 subsets between Th1- and Th2-mediated diseases using CD1a and CD141, and to analyze the adequacy of CD1a and CD141 as a marker for mDC1s and mDC2s, respectively.Methods
Thirty patients with sarcoidosis, 23 patients with atopic diseases, such as atopic bronchial asthma, and 23 healthy subjects as controls were enrolled in this study. Peripheral blood DC subsets were analyzed with flow cytometry according to expressions of CD11c, CD123, CD1a, and CD141. For functional analysis, we measured interleukin (IL) 12p40 levels produced by the sorted mDC subsets.Results
The sarcoidosis group showed decreased total DC (P < 0.05) and mDC counts (P < 0.05) compared to controls. The atopy group showed decreased CD1a+mDC count (P < 0.05), and increased CD1a-mDC count (P < 0.05) compared to controls. CD141+mDC count in the atopy group was higher than controls (P < 0.05). Sorted CD1a+mDCs produced higher levels of IL-12p40 than CD1a-mDCs (P = 0.025) and CD141+mDCs (P = 0.018).Conclusions
We conclude that decreased count of CD1a+mDC and increased count of CD141+mDC may reflect the Th2-skewed immunity in atopic diseases. The results of IL-12 levels produced by the sorted mDC subsets suggested the adequacy of CD1a and CD141 as a marker for mDC1 and mDC2, respectively, in vivo. 相似文献166.
A method was developed and applied for monitoring two types of fast-start locomotion (feeding and escape) of a cruiser fish, Japanese amberjacks Seriola quinqueradiata. A data logger, which incorporated a 3-axis gyroscope, a 3-axis accelerometer and a 3-axis magnetometer, was attached to the five fish. The escape, feeding and routine movements of the fish, which were triggered in tank experiments, were then recorded by the data logger and video cameras. The locomotor variables, calculated based on the high resolution measurements by the data logger (500 Hz), were investigated to accurately detect and classify the types of fast-track behaviour. The results show that fast-start locomotion can be detected with a high precision (0.97) and recall rate (0.96) from the routine movements. Two types of fast-start movements were classified with high accuracy (0.84). Accuracy was greater if the data were obtained from the data logger, which combined an accelerometer, a gyroscope and a magnetometer, than if only an accelerometer (0.80) or a gyroscope (0.66) was used. 相似文献
167.
Junichi Okuyama Kana Nakajima Takuji Noda Satoko Kimura Hiroko Kamihata Masato Kobayashi Nobuaki Arai Shiro Kagawa Yuuki Kawabata Hideaki Yamada 《PloS one》2013,8(6)
Animals are assumed to obtain/conserve energy effectively to maximise their fitness, which manifests itself in a variety of behavioral strategies. For marine animals, however, these behavioral strategies are generally unknown due to the lack of high-resolution monitoring techniques in marine habitats. As large marine herbivores, immature green turtles do not need to allocate energy to reproduction but are at risk of shark predation, although it is a rare occurrence. They are therefore assumed to select/use feeding and resting sites that maximise their fitness in terms of somatic growth, while avoiding predation. We investigated fine-scale behavioral patterns (feeding, resting and other behaviors), microhabitat use and time spent on each behavior for eight immature green turtles using data loggers including: depth, global positioning system, head acceleration, speed and video sensors. Immature green turtles at Iriomote Island, Japan, spent an average of 4.8 h feeding on seagrass each day, with two peaks, between 5∶00 and 9∶00, and between 17∶00 and 20∶00. This feeding pattern appeared to be restricted by gut capacity, and thus maximised energy acquisition. Meanwhile, most of the remaining time was spent resting at locations close to feeding grounds, which allowed turtles to conserve energy spent travelling and reduced the duration of periods exposed to predation. These behavioral patterns and time allocations allow immature green turtles to effectively obtain/conserve energy for growth, thus maximising their fitness. 相似文献
168.
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169.
170.
Yohsuke Ohba Eriko Kage‐Nakadai Naoko H Tomioka Nozomu Kono Rieko Imae Asuka Inoue Junken Aoki Naotada Ishihara Shohei Mitani Hiroyuki Arai 《The EMBO journal》2013,32(9):1265-1279
Glycerol‐3‐phosphate acyltransferase (GPAT) is involved in the first step in glycerolipid synthesis and is localized in both the endoplasmic reticulum (ER) and mitochondria. To clarify the functional differences between ER‐GPAT and mitochondrial (Mt)‐GPAT, we generated both GPAT mutants in C. elegans and demonstrated that Mt‐GPAT is essential for mitochondrial fusion. Mutation of Mt‐GPAT caused excessive mitochondrial fragmentation. The defect was rescued by injection of lysophosphatidic acid (LPA), a direct product of GPAT, and by inhibition of LPA acyltransferase, both of which lead to accumulation of LPA in the cells. Mitochondrial fragmentation in Mt‐GPAT mutants was also rescued by inhibition of mitochondrial fission protein DRP‐1 and by overexpression of mitochondrial fusion protein FZO‐1/mitofusin, suggesting that the fusion/fission balance is affected by Mt‐GPAT depletion. Mitochondrial fragmentation was also observed in Mt‐GPAT‐depleted HeLa cells. A mitochondrial fusion assay using HeLa cells revealed that Mt‐GPAT depletion impaired mitochondrial fusion process. We postulate from these results that LPA produced by Mt‐GPAT functions not only as a precursor for glycerolipid synthesis but also as an essential factor of mitochondrial fusion. 相似文献