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51.
Fu Lv Yingxin He Hongde Xu Yongchun Li Lipei Han Lijie Yan Hui Lang Yafei Zhao Zhanzheng Zhao Yuanyuan Qi 《Cell death & disease》2022,13(8)
A major cause of proteinuria in lupus nephritis (LN) is podocyte injury, and determining potential therapeutic targets to prevent podocyte injury is important from a clinical perspective in the treatment of LN. CD36 is involved in podocyte injury in several glomerulopathies and was reported to be a vital candidate gene in LN. Here, we determined the role of CD36 in the podocyte injury of LN and the underlying mechanisms. We observed that CD36 and NLRP3 (NLR family pyrin domain containing 3) were upregulated in the podocytes of lupus nephritis patients and MRL/lpr mice with renal impairment. In vitro, CD36, NLRP3 inflammasome, and autophagy were elevated accompanied with increased podocyte injury stimulated by IgG extracted from lupus nephritis patients compared that from healthy donors. Knocking out CD36 with the CRISPR/cas9 system decreased the NLRP3 inflammasome levels, increased the autophagy levels and alleviated podocyte injury. By enhancing autophagy, NLRP3 inflammasome was decreased and podocyte injury was alleviated. These results demonstrated that, in lupus nephritis, CD36 promoted podocyte injury by activating NLRP3 inflammasome and inhibiting autophagy by enhancing which could decrease NLRP3 inflammasome and alleviate podocyte injury.Subject terms: Mechanisms of disease, Inflammasome, Lupus nephritis, Autophagy 相似文献
52.
文中旨在研究粒细胞集落刺激因子(Granule cell stimulating factor,GCSF)对绵羊颗粒细胞体外培养过程中细胞增殖和凋亡的影响,明确GCSF对绵羊颗粒细胞生存的调节作用,为今后该蛋白用于羊繁育方面的研究奠定基础。原核克隆表达纯化羊GCSF蛋白,纯化的蛋白用M-NSF60细胞检测生物学活性,将纯化的GCSF添加到颗粒细胞培养基中作为试验组,以培养基中未添加GCSF的细胞为对照,利用Alarmarblue检测细胞增殖情况,流式细胞仪检测细胞周期和凋亡的变化。结果表明,羊GCSF可以原核表达并纯化,并且具有生物学活性。在24 h和48 h时,在0.06–600 ng/mL的范围内随着加入GCSF的终浓度增加,细胞活力升高。试验组颗粒细胞体外培养24 h后,与阴性对照相比,细胞周期的分布显著改变,S期细胞比例显著减少(P<0.05),G2/M期细胞比例显著增多(P<0.05)。试验组凋亡率和对照组相比,48 h检测时凋亡率显著降低(P<0.05)。综上表明,GCSF在体外培养的绵羊颗粒细胞中,可调控绵羊颗粒细胞周期,促进细胞增殖,抑制细胞凋亡。 相似文献
53.
在贵州省六盘水市杨梅乡慕尼克村,利用陷阱法捕捉到3号麝鼩属(Crocidura)标本。本次采集标本的体形较小,头体长(49.0 ± 0.8)mm,尾长[(41.8 ± 4.2)mm]略短于头体长(尾长/头体长为85%)。背毛呈浅灰褐色,腹毛颜色浅于背毛,呈灰色。尾部双色,背侧黑褐色,腹侧淡于背侧。前足背部白色,后足则为淡灰色。尾近乎裸露,尾基约1/3着生稀疏白色长毛。颅全长(15.92 ± 0.55)mm,脑颅高(4.75 ± 0.18)mm。上门齿1枚,有一长而大的前尖和一小而矮的后尖。上单尖齿3枚,第1单尖齿最大,第2单尖齿略大于第3单尖齿,1枚第四前臼齿(P4),3枚臼齿。上述特征与东阳江麝鼩(C. dongyangjiangensis)模式标本的描述和鉴定特征基本一致,因此将3号采集标本鉴定为东阳江麝鼩。基于Cyt b基因进行分子系统发育分析,采集标本与麝鼩属物种中的东阳江麝鼩遗传距离最近,在0.004 ~ 0.027之间。系统发生树显示,3号标本与东阳江麝鼩构成一个单系进化分支,进一步证实本次采集的3号标本是东阳江麝鼩,为贵州省分布新记录种。 相似文献
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57.
沿海快速城市化地区能值生态足迹变化分析 总被引:1,自引:0,他引:1
当前我国经济的快速发展和生态环境之间的矛盾日益显著,不利于城市可持续发展。生态足迹目前已成为普遍接受的可持续发展指标,选定生态足迹改进方法——能值生态足迹模型,以城市化地区厦门市为研究区进行计算分析,以期发现快速城市化过程中可能面对的问题。首次计算分析了厦门市1980年至2010年的能值生态足迹动态变化,并对其可持续发展进行了评价。结果表明,30年间厦门市人均生态足迹需求从1980年的8.6 ghm2持续增长至2010年的52.8 ghm2,而供给方面的人均生态承载力却从1980年的181.2 ghm2持续下降为47.5 ghm2,2009、2010年该市由生态盈余转为生态赤字。同时,从生态足迹组分及其比例来看,30年间化石燃料用地和建设用地的生态足迹增长迅速,二者对厦门市人均能值生态足迹变化贡献最大,并且成为2000年后总体足迹中所占比例最大的组分,各自占比超过20%。结果分析显示,厦门市开始面临逐渐加重的生态环境压力,需要开始重视其可持续发展。因此调整厦门市的产业结构和控制城市化发展非常必要。一方面,应该降低第二产业的比例,降低对化石能源的使用,同时促进第三产业的发展和第一产业的现代化,以此为城市提供更多的资源供给并降低资源需求,特别是化石能源的需求。 相似文献
58.
Wenqiao He Yuhan Gao Yuqi Wen Xuemei Ke Zejin Ou Jiaqi Fu Mingji Cheng Yun Mo Qing Chen 《中国病毒学》2022,37(2):215-222
Bocaviruses are associated with many human infectious diseases, such as respiratory tract infections, gastroenteritis, and hepatitis. Rats are known to be reservoirs of bocaviruses, including rodent bocavirus and rat bocavirus. Recently, ungulate bocaparvovirus 4, a known porcine bocavirus, has also been found in rats. Thus, investigating bocaviruses in rats is important for determining the origin of the viruses and preventing and controlling their transmission. To the best of our knowledge, no study to date has investigated bocaviruses in the livers of rats. In this report, a total of 624 rats were trapped in southern China between 2014 and 2017. Liver and serum samples from rats were tested for the prevalence of bocaviruses using PCR. Sequences related to ungulate bocaparvovirus 4 and rodent bocavirus were detected in both liver and serum samples. Interestingly, the prevalence of ungulate bocaparvovirus 4 (reference strain:KJ622366.1) was higher than that of rodent bocavirus (reference strain:KY927868.1) in both liver (2.24% and 0.64%, respectively) and serum samples (2.19% and 0.44%, respectively). The NS1 regions of ungulate bocaparvovirus 4 and rodent bocavirus related sequences displayed over 84% and 88% identity at the nucleic acid and amino acid levels, respectively. Furthermore, these sequences had similar genomic structure, genomic features, and codon usage bias, and shared a common ancestor. These viruses also displayed greater adaptability to rats than pigs. Our results suggested that ungulate bocaparvovirus 4 and rodent bocavirus may originate from rats and may be different genotypes of the same bocavirus species. 相似文献
59.
Jindong Zhang Vanessa Hull Zhiyun Ouyang Liang He Thomas Connor Hongbo Yang Jinyan Huang Shiqiang Zhou Zejun Zhang Caiquan Zhou Hemin Zhang Jianguo Liu 《Ecology and evolution》2017,7(8):2575-2584
The study of wildlife activity patterns is an effective approach to understanding fundamental ecological and evolutionary processes. However, traditional statistical approaches used to conduct quantitative analysis have thus far had limited success in revealing underlying mechanisms driving activity patterns. Here, we combine wavelet analysis, a type of frequency‐based time‐series analysis, with high‐resolution activity data from accelerometers embedded in GPS collars to explore the effects of internal states (e.g., pregnancy) and external factors (e.g., seasonal dynamics of resources and weather) on activity patterns of the endangered giant panda (Ailuropoda melanoleuca). Giant pandas exhibited higher frequency cycles during the winter when resources (e.g., water and forage) were relatively poor, as well as during spring, which includes the giant panda's mating season. During the summer and autumn when resources were abundant, pandas exhibited a regular activity pattern with activity peaks every 24 hr. A pregnant individual showed distinct differences in her activity pattern from other giant pandas for several months following parturition. These results indicate that animals adjust activity cycles to adapt to seasonal variation of the resources and unique physiological periods. Wavelet coherency analysis also verified the synchronization of giant panda activity level with air temperature and solar radiation at the 24‐hr band. Our study also shows that wavelet analysis is an effective tool for analyzing high‐resolution activity pattern data and its relationship to internal and external states, an approach that has the potential to inform wildlife conservation and management across species. 相似文献
60.
微乳体系中11β-羟基甲羟孕酮的C1,2生物脱氢 总被引:1,自引:0,他引:1
为改善过程传质,提高甾类药物中间体11β-羟基甲羟孕酮C1,2生物脱氢转化率,采用简单节杆菌Arthrobacter simplex UR016菌株在Tween-80/乙醇/食油/水构成的微乳体系中进行生物脱氢,并考察了微乳体系组成、转化温度、投料浓度对脱氢反应的影响。结果表明:以菌体培养液作为水相,食油作为油相构建微乳体系,食油最适加量为10g/L,表面活性剂Tween-80加量为4g/L;底物经醇溶后水析投料,乙醇最适加量为发酵液体积的7%(V/V);最适转化温度为33oC;当底物浓度为4g/L时,在构建的微乳体系中转化46h,脱氢转化率达88.6%,与水相转化工艺相比提高了66.2%。在该体系中疏水性11β-羟基甲羟孕酮底物得到了有效的增溶和扩散,生物脱氢转化率明显提高。 相似文献