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71.
Kenichiro Iio Hirotsugu Iwatani Arata Horii Yoshiyuki Furumatsu Hiroshi Nojima Yoshitaka Isaka 《Biochemical and biophysical research communications》2010,393(4):565-570
Background
Recently, combination of tonsillectomy and steroid pulse therapy was reported to be effective as the treatment of the immunoglobulin A nephropathy (IgAN). However, the gene expression difference between the tonsils in patients with IgAN and those in control patients is not established.Methods
We performed tonsillectomy combined with steroid pulse as a treatment to IgAN, analyzed the gene expression in the tonsils (N = 23) using microarray, compared with those with patients suffering from chronic tonsillitis (N = 22). From some candidate genes related with IgAN, we confirmed the apolipoprotein B messenger RNA-editing enzyme catalytic polypeptides 2 (APOBEC2) gene expression in the tonsil and we also analyzed its expression levels and clinical features.Results
Up-regulated genes seem to be categorized into two groups. One group belongs to the muscle related genes which might be caused by structural differences. The other group includes the immune system-related genes, such as APOBEC2, CALB2, DUSP27, and CXCL11. APOBEC2 was positively stained in the epithelium and the peripheral region of the germinal center in both tonsils. APOBEC2 expression level was negatively related with serum igg level, but did not correlate with clinical course after tonsillectomy.Conclusion
We confirmed gene expression differences related with immune system and muscle structure. The APOBEC2 was confirmed to be elevated in the tonsils with IgAN patients, and the gene expression level was negatively related with serum igg level in overall patients. These results might be helpful to reveal the mechanism of IgAN. 相似文献72.
Expression of Six Proteins Causes Reprogramming of Porcine Fibroblasts Into Induced Pluripotent Stem Cells With Both Active X Chromosomes 下载免费PDF全文
Tomokazu Fukuda Tetsuya Tani Seiki Haraguchi Kenichiro Donai Nobuyoshi Nakajima Hirohide Uenishi Takahiro Eitsuka Makoto Miyagawa Sanghoun Song Manabu Onuma Yumi Hoshino Eimei Sato Arata Honda 《Journal of cellular biochemistry》2017,118(3):537-553
In this study, we created porcine‐induced pluripotent stem (iPS) cells with the expression of six reprogramming factors (Oct3/4, Klf4, Sox2, c‐Myc, Lin28, and Nanog). The resulting cells showed growth dependent on LIF (leukemia inhibitory factor) and expression of multiple stem cell markers. Furthermore, the iPS cells caused teratoma formation with three layers of differentiation and had both active X chromosomes (XaXa). Our iPS cells satisfied the both of important characteristics of stem cells: teratoma formation and activation of both X chromosomes. Injection of these iPS cells into morula stage embryos showed that these cells participate in the early stage of porcine embryogenesis. Furthermore, the RNA‐Seq analysis detected that expression levels of endogenous pluripotent related genes, NANOG, SOX2, ZFP42, OCT3/4, ESRRB, and ERAS were much higher in iPS with six factors than that with four reprogramming factors. We can conclude that the expression of six reprogramming factors enables the creation of porcine iPS cells, which is partially close to naive iPS state. J. Cell. Biochem. 118: 537–553, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
73.
Maki Fukami Erina Suzuki Yoko Izumi Tomohiro Torii Satoshi Narumi Maki Igarashi Mami Miyado Momori Katsumi Yasuko Fujisawa Kazuhiko Nakabayashi Kenichiro Hata Akihiro Umezawa Yoichi Matsubara Junji Yamauchi Tsutomu Ogata 《Journal of cellular and molecular medicine》2017,21(10):2623-2626
The human genome encodes ~750 G‐protein‐coupled receptors (GPCRs), including prokineticin receptor 2 (PROKR2) involved in the regulation of sexual maturation. Previously reported pathogenic gain‐of‐function mutations of GPCR genes invariably encoded aberrant receptors with excessive signal transduction activity. Although in vitro assays demonstrated that an artificially created inactive mutant of PROKR2 exerted paradoxical gain‐of‐function effects when co‐transfected with wild‐type proteins, such a phenomenon has not been observed in vivo. Here, we report a heterozygous frameshift mutation of PROKR2 identified in a 3.5‐year‐old girl with central precocious puberty. The mutant mRNA escaped nonsense‐mediated decay and generated a GPCR lacking two transmembrane domains and the carboxyl‐terminal tail. The mutant protein had no in vitro signal transduction activity; however, cells co‐expressing the mutant and wild‐type PROKR2 exhibited markedly exaggerated ligand‐induced Ca2+ responses. The results indicate that certain inactive PROKR2 mutants can cause early puberty by enhancing the functional property of coexisting wild‐type proteins. Considering the structural similarity among GPCRs, this paradoxical gain‐of‐function mechanism may underlie various human disorders. 相似文献
74.
A predictive software system, SOSUI-GramN, was developed for assessing the subcellular localization of proteins in Gram-negative bacteria. The system does not require the sequence homology data of any known sequences; instead, it uses only physicochemical parameters of the N- and C-terminal signal sequences, and the total sequence. The precision of the prediction system for subcellular localization to extracellular, outer membrane, periplasm, inner membrane and cytoplasmic medium was 92.3%, 89.4%, 86.4%, 97.5% and 93.5%, respectively, with corresponding recall rates of 70.3%, 87.5%, 76.0%, 97.5% and 88.4%, respectively. The overall performance for precision and recall obtained using this method was 92.9% and 86.7%, respectively. The comparison of performance of SOSUI-GramN with that of other methods showed the performance of prediction for extracellular proteins, as well as inner and outer membrane proteins, was either superior or equivalent to that obtained with other systems. SOSUI-GramN particularly improved the accuracy for predictions of extracellular proteins which is an area of weakness common to the other methods. 相似文献
75.
Arase S Ishii K Igarashi K Aisaki K Yoshio Y Matsushima A Shimohigashi Y Arima K Kanno J Sugimura Y 《Biology of reproduction》2011,84(4):734-742
The balance between androgens and estrogens is very important in the development of the prostate, and even small changes in estrogen levels, including those of estrogen-mimicking chemicals, can lead to serious changes. Bisphenol A (BPA), an endocrine-disrupting chemical, is a well-known, ubiquitous, estrogenic chemical. To investigate the effects of fetal exposure to low-dose BPA on the development of the prostate, we examined alterations of the in situ sex steroid hormonal environment in the mouse urogenital sinus (UGS). In the BPA-treated UGS, estradiol (E(2)) levels and CYP19A1 (cytochrome P450 aromatase) activity were significantly increased compared with those of the untreated and diethylstilbestrol (DES)-treated UGS. The mRNAs of steroidogenic enzymes, Cyp19a1 and Cyp11a1, and the sex-determining gene, Nr5a1, were up-regulated specifically in the BPA-treated group. The up-regulation of mRNAs was observed in the mesenchymal component of the UGS as well as in the cerebellum, heart, kidney, and ovary but not in the testis. The number of aromatase-expressing mesenchymal cells in the BPA-treated UGS was approximately twice that in the untreated and DES-treated UGS. The up-regulation of Esrrg mRNA was observed in organs for which mRNAs of steroidogenic enzymes were also up-regulated. We demonstrate here that fetal exposure to low-dose BPA has the unique action of increasing in situ E(2) levels and CYP19A1 (aromatase) activity in the mouse UGS. Our data suggest that BPA might interact with in situ steroidogenesis by altering tissue components, such as the accumulation of aromatase-expressing mesenchymal cells, in particular organs. 相似文献
76.
Takahiro Kuragano Kenichiro Kitamura Osamu Matsumura Akihiko Matsuda Taiga Hara Hideyasu Kiyomoto Toshiaki Murata Shouichi Fujimoto Hiroki Hase Nobuhiko Joki Atushi Fukatsu Toru Inoue Yukihiro Itakura Takeshi Nakanishi 《PloS one》2016,11(3)
Objective
It has been reported that hyporesponsiveness to erythropoiesis-stimulating agent (ESA) is associated with adverse events in patients on maintenance hemodialysis (MHD). However, it has not been determined whether higher iron storage is associated with an improved response, including better survival, to ESA.Design and Method
We measured serum ferritin, hemoglobin (Hb), and transferrin saturation (TSAT) levels every three months for two years in 1,095 MHD patients. The weekly dose of ESA to Hb ratio was also calculated as an index of ESA responsiveness (ERI).Results
A significant correlation (p<0.001, R = 0.89) between ferritin and Hb was only observed in the patients with ferritin levels <50 ng/mL. High-dose (≥50 mg/week) intravenous iron administration, female sex, low serum albumin, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use were significant predictors of a high ERI value (>280); however, serum ferritin and TSAT levels did not predict a higher ERI. In the time-dependent Cox hazard model, the risk for a composite event in the patients with a high ERI (≥280) and a high ferritin level (≥100 ng/mL) was significantly greater (hazard ratio [HR], 2.09, P = 0.033) than that for patients with a high ERI and a low ferritin (<100 ng/mL) level.Conclusion
Hb was dependent upon ferritin levels in patients with ferritin levels <50 ng/mL but not in patients with ferritin levels ≥50 ng/mL. Patients with hyporesponsiveness to ESA had a greater risk of composite events, but ERI was unrelated to iron storage. 相似文献77.
Yoichi Sato Tomonari Hirano Hiroyuki Ichida Motoko Murakami Nobuhisa Fukunishi Tomoko Abe Shigeyuki Kawano 《Journal of applied phycology》2017,29(5):2287-2295
Undaria pinnatifida is grown for food and industrial materials worldwide; therefore, advanced breeding is needed to meet quality and productivity requirements. In this study, we examined regional lines of U. pinnatifida from five cultivation sites in Japan with different environmental conditions: Oga (OGA, the northern Sea of Japan coast), Hirota Bay (HRT, the northeastern Pacific coast), Matsushima Bay (MAT, the northeastern Pacific coast), Naruto (the Seto Inland Sea coast) and Shimonoseki (SIM, the southern Sea of Japan coast). The sporophytes of these lines were cultured in a tank culture system under controlled environmental conditions, and their morphological characteristics, nutrient uptake kinetics (V max, K s and V max/K s ), and carbon, nitrogen and phosphorus contents were determined. Sporophytes from MAT grew faster, whereas those from SIM were smaller than those from the other sites. Although the blade thickness of sporophytes cultivated in the sea significantly differs among cultivation sites in the previous study, there was no significant difference in blade thickness among the regional lines cultivated in the tank. Sporophytes from OGA had the greatest V max/K s values and significantly greater nitrogen contents than the other lines. Therefore, the morphological characteristics of MAT and SIM sporophytes, and the nutrient uptake kinetics of OGA sporophytes may have a genetic origin. This indicates that these lines may represent useful resources for selective breeding, with MAT sporophytes providing faster growth and OGA sporophytes being well-adapted to low-nutrient conditions. 相似文献
78.
Origin of two isoprenoid units in a lavandulyl moiety of sophoraflavanone G from Sophora flavescens cultured cells 总被引:2,自引:0,他引:2
Cell suspension cultures of Sophora flavescens produced large amounts of sophoraflavanone G, an 8-lavandulylated flavanone and lupalbigenin, a 6,3'-di-dimethylallylated isoflavone, by the simultaneous addition of cork tissues and methyl jasmonate. The labeling pattern of the isoprene units resulting after administration of [1-13C] glucose into the cell cultures in the presence of the above additives revealed that two isoprene units in the lavandulyl group of sophoraflavanone G and two dimethylallyl groups of lupalbigenin were biosynthesized via the 1-deoxy-D-xylulose-5-phosphate pathway. 相似文献
79.
江西鄱阳湖是长江江豚(Neophocaena phocaenoides)的重要栖息地, 湖中栖息着约400 头江豚。多年的观察表明, 船舶交通是鄱阳湖中江豚面临的重要威胁之一。为了评估船舶通行对长江江豚发声行为的影响,尤其是了解船舶通行期间及其前后江豚的发声和行为特征, 作者于2007 年6 月27 日—7 月1 日在江西鄱阳湖湖口水域采用固定被动声学系统, 即安装在监测点(29°42′38″ N, 116°11′11″ E)的一套水下声学数据记录系统, 对周边通行船舶的水下噪声及江豚声纳信号脉冲事件进行了定点监测和记录, 并对所记录的数据进行了定量和统计分析。在整个监测的109h 中, 声学记录仪共记录到船舶494 艘, 江豚声纳脉冲串信号13413个。船舶出现与江豚出现存在弱的负相关关系(r = -0.029, N = 6550, P Z = -0.370, P> 0.05); 当有船舶经过时, 江豚的发声频次显著降低(Z = -10.050, P Z = -0.275, P> 0.05; Z = -0.119, P> 0.05); 船舶通行之前和之后, 江豚的发声频次、脉冲串持续时间、脉冲间间隔的差异性均不显著(χ2= 5.255, P> 0.05; χ2= 3.511, P> 0.05; χ2= 5.155, P>0.05); 在船舶经过时, 江豚对游动方向没有明显的选择性(χ2= 0.861, P> 0.05)。基于分析结果推测, 在狭窄水域中江豚躲避船舶干扰通常采取“临时性”策略, 而非长距离逃避。由于鄱阳湖湖口水域水道相对狭窄, 尽管研究的结果表明江豚对船舶有一定的敏感反应, 但是在相对狭窄的水域中, 江豚躲避船舶的行为难以充分表现。另外, 江豚对该水域中高密度航行船舶的噪声可能存在一定的“适应性”, 导致当遭遇船舶时, 江豚的声行为反应不十分强烈。因此, 建议有必要在不同尺度的水体中采用声学数据记录仪继续开展类似的观察,以进一步了解江豚对船舶的行为响应, 尤其是观察江豚躲避船舶的行为及发声特征 相似文献
80.
水生哺乳动物(主要是鲸类和鳍脚类)分布范围广、活动范围大、行为复杂,且在水下活动时间长,常规的目视观察受时间和空间限制,通常只能获取有限的信。信标跟踪记录(Bio-logging)具有可跟随移动和自主操作的特征,能在很大程度上突破时间和空间限制,实时获取动物及其栖息环境信息。水生哺乳动物的信标跟踪记录始于20世纪60年代[1,2],40年来,无论是记录技术,还是应用研究,都有了很大发展。2003年在日本东京国立极地研究所召开的“信标跟踪记录科学国际学术讨论会(International Symposium on Bio-loggingScience)”,收到来自法、美、英、日、澳、德、意、加、南非和中国共152名与会代表的104篇论文。这些论文主要介绍信标跟踪记录技术及其应用的现状和未来趋势。会议以不同研究对象分专题进行交流,共分为鲸类、鳍脚类、类、爬行类、鱼类和其他类6个专题,其中鸟类专题论文最多,其次是鱼类专题。有关水生哺乳动物的研究论文共22篇,除了4篇介绍记录技术外,其他论文主要介绍信标跟踪记录的应用研究,包括潜水行为、捕食策略、能量代谢、栖息地标识和发声策略研究。本文是近年来水生哺乳动物信标跟踪记录研究领域相关论文的综述,除介绍水生哺乳动物信标跟踪记录技术及其应用研究现状外,还对其不足之处和可能的发展趋势进行了讨论。此外,还重点介绍了我国珍稀动物长江江豚(Neophocaena phocaenoides as iaeorientalis)信标跟踪研究的一些进展。 相似文献