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121.
Xin Li Tian-Tian Li Xiao-Hui Zhang Li-Fei Hou Xiao-Qian Yang Feng-Hua Zhu Wei Tang Jian-Ping Zuo 《PloS one》2013,8(8)
Background
Artemisinin analogue SM934 was previously reported to possess immunosuppressive properties. The aim of this study was to determine the effects and the underlying mechanisms of SM934 in murine experimental autoimmune encephalomyelitis (EAE).Methods
Female C57BL/6 mice immunized with MOG35–55 were treated with or without SM934, then the clinical scores and other relevant parameters were assessed. Th1, Th17 and regulatory T (Treg) cell profiles were determined through ELISA, qRT-PCR, flow cytometry and BrdU incorporation assay. The effects of SM934 on Th1, Th17 and Treg cells differentiation were explored through intracellular staining and flow cytometry examination.Results
In vivo, administration of SM934 significantly inhibited the development of EAE and suppressed the elevation of serum IL-17. Ex vivo, upon antigen-recall stimulation, IL-2, IFN-γ, IL-17 and IL-6 production were decreased, whereas IL-10 and TGF-β production were increased from the splenocytes isolated from SM934-treated mice. Consistently, both flow cytometry and qRT-PCR results showed that SM934 treatment significantly increased the Treg, while strongly suppressed the Th17 and Th1, responses in the peripheral. Furthermore, in the spinal lesion, SM934 treatment dramatically decreased the infiltration of CD4+ T cells, within which the Treg cells percentage was enlarged, whereas the Th17, but not Th1 percentage, was significantly decreased comparing with the vehicle-treated groups. Finally, both BrdU incorporation and in vitro Treg differentiation assays revealed that SM934 treatment could directly promote the expansion of Treg cells in vivo and in vitro.Conclusion
Taken together, this study demonstrated that SM934 treatment could ameliorate the murine EAE disease, which might be mediated by inducing Treg differentiation and expansion. 相似文献122.
123.
长白猪、枫泾猪和它们的杂种后代Ag—NOR的研究 总被引:11,自引:0,他引:11
4头枫泾猪,3头长白猪和5头长白×枫泾杂一代的NOR平均数分别为3.88、2和2.95。33头长白×枫泾杂二代猪(杂一代互交后代),其中7头黑猪的NOR众数为4,平均数为3.85;9头白猪的NOR众数为2,平均数为2.25;14头白猪的NOR众数为3,平均数为2.86;3头花猪的NOR众数分别为4.3、3,平均数为3.65、3.00和3.08。根据长白、枫泾和长白×枫泾杂一代和杂二代的NOR数目的区别和变化,NOR的遗传符合孟德尔定律。根据NOR数目与毛色的高度相关,提出了决定猪的黑白毛色的基因位于8号染色体并与NOR连锁的假设。猪的毛色除由位于8号染色体上的毛色基因所决定外,还应受其它基因位点的影响。 相似文献
124.
Mingjun Wang Jian Wu Erye Zhou Xin Chang Jianhe Gan Tao Cheng 《Journal of cellular physiology》2019,234(11):20139-20148
125.
A complete and high‐quality genome reference sequence of an organism provides a solid foundation for a wide research community and determines the outcomes of relevant genomic, genetic, molecular and evolutionary research. Rice is an important food crop and a model plant for grasses, and therefore was the first chosen crop plant for whole genome sequencing. The genome of the japonica representative rice variety, Nipponbare, was sequenced using a gold standard, map‐based clone‐by‐clone strategy. However, although the Nipponbare reference sequence (RefSeq) has the best quality for existing crop genome sequences, it still contains many assembly errors and gaps. To improve the Nipponbare RefSeq, first a robust method is required to detect the hidden assembly errors. Through alignments between BAC‐end sequences (BESs) embedded in the Nipponbare bacterial artificial chromosome (BAC) physical map and the Nipponbare RefSeq, we detected locations on the Nipponbare RefSeq that were inversely matched with BESs and could therefore be candidates for spurious inversions of assembly. We performed further analysis of five potential locations and confirmed assembly errors at those locations; four of them, two on chr4 and two on chr11 of the Nipponbare RefSeq (IRGSP build 5), were found to be caused by reverse repetitive sequences flanking the locations. Our approach is effective in detecting spurious inversions in the Nipponbare RefSeq and can be applied for improving the sequence qualities of other genomes as well. 相似文献
126.
Yakai Xin Yu Guo Yanle Li Yujin Ma Liping Li Hongwei Jiang 《Saudi Journal of Biological Sciences》2019,26(2):421-426
To describe the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on serum uric acid (SUA) in patients with type 2 diabetes mellitus (T2DM). PubMed, EMBASE, and CENTRAL were searched for randomized controlled trials of SGLT2 inhibitors in patients with T2DM up to Aug 10, 2017, without language or date restrictions. Thirty-one studies totaling 13,650 patients were included. SGLT2 inhibitors significantly decreased SUA levels compared with placebo, canagliflozin WMD –37.02?μmol/L, 95% CI [–38.41, –35.63], dapagliflozin WMD –38.05?μmol/L, 95% CI [–44.47, –31.62], empagliflozin WMD –42.07?μmol/L, 95% CI [–46.27, –37.86]. The drug class effect of SUA reduction suggesting SGLT2 inhibitors might be beneficial for diabetic patients with hyperuricemia. 相似文献
127.
Rui Cheng Xiaoman Zheng Yingmei Wang Xing Ma Xin Liu Wenjun Xu Mengyun Wang Yuanpeng Gao Xupeng Xing Chuan Zhou Hongzheng Sun Zekun Guo Fusheng Quan Jun Liu Song Hua Yongsheng Wang Yong Zhang Xu Liu 《中国科学:生命科学英文版》2022,65(11):2257-2268
Animal cloning can be achieved by somatic cell nuclear transfer(SCNT), but the resulting live birth rate is relatively low. We previously improved the efficiency of bovine SCNT by exogenous melatonin treatment or by overexpression of lysine-specific demethylase 4D(KDM4D) and 4E(KDM4E). In this study, we revealed abundant alternative splicing(AS) transitions during fertilization and embryonic genome activation, and demonstrated abnormal AS in bovine SCNT embryos compared with in vitro fertilized ... 相似文献
128.
野葛藤茎的异黄酮类化学成分 总被引:8,自引:0,他引:8
从野葛Pueraria lobata(Willd.)Ohwi藤茎中分离得到5个异黄酮类化合物,分别鉴定为:大豆甙元(daidzein),芒柄花异黄酮(formononetin),6,7-二甲氧基-3’,4’-次甲二氧基异黄酮(6,7-dimethoxy-3’,4’-methlenedioxyisoflavone),大豆甙(daidzin)和葛根素(puerarin). 相似文献
129.
陕西紫阳地区在古地理上位于扬子台地西北缘,区域内志留纪地层发育,其中志留系兰多维列统(Llandovery)特列奇阶(Telychian)笔石相地层出露较为完整,笔石带较为连续。Oktavites excentricus(Bjerreskov,1975)是特列奇阶Oktavites spiralis笔石带重要的伴生分子,在世界范围内广泛分布。文中通过对紫阳地区一系列特列奇阶剖面研究后认为,Oktavites excentricus较短的化石延限和广泛的古地理分布使其具备地层对比潜力,这将为Oktavites spiralis笔石带的进一步细分提供依据。同时,Oktavites excentricus胞管为典型的奥氏笔石式,其笔石体的盘旋方式又与稍晚的Cyrtograptus lapworthi(Tullberg,1883)(笔石带化石,弓笔石类的早期代表)十分接近,因此,对该种的演化过程的研究也为讨论弓笔石的起源过程提供了更多参考。 相似文献
130.
Characterization of the tunicamycin gene cluster unveiling unique steps involved in its biosynthesis
Wenqing Chen Dongjing Qu Lipeng Zhai Meifeng Tao Yemin Wang Shuangjun Lin Neil P. J. Price Zixin Deng 《蛋白质与细胞》2010,1(12):1093
Tunicamycin, a potent reversible translocase I inhibitor, is produced by several Actinomycetes species. The tunicamycin structure is highly unusual, and contains an 11-carbon dialdose sugar and an α, β -1″,11′-glycosidic linkage. Here we report the identification of a gene cluster essential for tunicamycin biosynthesis by high-throughput heterologous expression (HHE) strategy combined with a bioassay. Introduction of the genes into heterologous non-producing Streptomyces hosts results in production of tunicamycin by these strains, demonstrating the role of the genes for the biosynthesis of tunicamycins. Gene disruption experiments coupled with bioinformatic analysis revealed that the tunicamycin gene cluster is minimally composed of 12 genes (tunA– tunL ). Amongst these is a putative radical SAM enzyme (Tun B) with a potentially unique role in biosynthetic carbon-carbon bond formation. Hence, a seven-step novel pathway is proposed for tunicamycin biosynthesis. Moreover, two gene clusters for the potential biosynthesis of tunicamycin-like antibiotics were also identified in Streptomyces clavuligerus ATCC 27064 and Actinosynnema mirums DSM 43827. These data provide clarification of the novel mechanisms for tunicamycin biosynthesis, and for the generation of new-designer tunicamycin analogs with selective/enhanced bioactivity via combinatorial biosynthesis strategies. 相似文献