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941.
Lei Zhu Ming Zhang Guanqing Zhou Tianyu Hao Jinqiu Xu Jing Wang Chaoqun Qiu Nathaniel Prine Jazib Ali Wei Feng Xiaodan Gu Zaifei Ma Zheng Tang Haiming Zhu Lei Ying Yongming Zhang Feng Liu 《Liver Transplantation》2020,10(18)
Single‐layered organic solar cells (OSCs) using nonfullerene acceptors have reached 16% efficiency. Such a breakthrough has inspired new sparks for the development of the next generation of OSC materials. In addition to the optimization of electronic structure, it is important to investigate the essential solid‐state structure that guides the high efficiency of bulk heterojunction blends, which provides insight in understanding how to pair an efficient donor–acceptor mixture and refine film morphology. In this study, a thorough analysis is executed to reveal morphology details, and the results demonstrate that Y6 can form a unique 2D packing with a polymer‐like conjugated backbone oriented normal to the substrate, controlled by the processing solvent and thermal annealing conditions. Such morphology provides improved carrier transport and ultrafast hole and electron transfer, leading to improved device performance, and the best optimized device shows a power conversion efficiency of 16.88% (16.4% certified). This work reveals the importance of film morphology and the mechanism by which it affects device performance. A full set of analytical methods and processing conditions are executed to achieve high efficiency solar cells from materials design to device optimization, which will be useful in future OSC technology development. 相似文献
942.
Ming He Miao Lan Baocai Zhang Yihua Zhou Youqun Wang Lei Zhu Ming Yuan Ying Fu 《植物学报(英文版)》2018,60(11):1051-1069
Cell-wall deposition of cellulose microfibrils is essential for plant growth and development. In plant cells,cellulose synthesis is accomplished by cellulose synthase complexes located in the plasma membrane. Trafficking of the complex between endomembrane compartments and the plasma membrane is vital for cellulose biosynthesis;however, the mechanism for this process is not well understood. We here report that, in Arabidopsis thaliana,Rab-H_1b, a Golgi-localized small GTPase, participates in the trafficking of CELLULOSE SYNTHASE 6(CESA6) to the plasma membrane. Loss of Rab-H_1b function resulted in altered distribution and motility of CESA6 in the plasma membrane and reduced cellulose content. Seedlings with this defect exhibited short, fragile etiolated hypocotyls.Exocytosis of CESA6 was impaired in rab-h1 b cells, and endocytosis in mutant cells was significantly reduced as well. We further observed accumulation of vesicles around an abnormal Golgi apparatus having an increased number of cisternae in rab-h1 b cells, suggesting a defect in cisternal homeostasis caused by Rab-H_1b loss function. Our findings link Rab GTPases to cellulose biosynthesis, during hypocotyl growth, and suggest Rab-H_1b is crucial for modulating the trafficking of cellulose synthase complexes between endomembrane compartments and the plasma membrane and for maintaining Golgi organization and morphology.e 相似文献
943.
Association between angiotensinogen (AGT) M235T gene polymorphism and end-stage renal disease (ESRD) risk is still controversial. This meta-analysis was performed to evaluate the association of AGT M235T gene polymorphism with ESRD susceptibility. A predefined literature search and selection of eligible relevant studies were performed to collect data from electronic databases of PubMed, Embase and Cochrane Library. Sixteen literatures were identified for the analysis of association of AGT M235T gene polymorphism with ESRD risk. T allele and TT genotype were associated with ESRD susceptibility in Caucasians (T: OR = 1.13, 95 % CI: 1.02–1.25, P = 0.02; TT: OR = 1.22, 95 % CI: 1.03–1.45, P = 0.02). However, MM genotype might not play a protective role against ESRD risk in Caucasians. Furthermore, there was no a markedly positive association between AGT M235T gene polymorphism and ESRD susceptibility in overall populations, Asians and Africans. In conclusion, T allele or TT homozygote is associated with the onset of ESRD in Caucasians. However, more studies should be performed in the future. 相似文献
944.
【目的】为了鉴定植原体tRNA异戊烯基焦磷酸转移酶基因(tRNA-ipt)的表达及蛋白功能,探索植原体致病机理。【方法】对泡桐丛枝、桑萎缩、长春花绿变及苦楝丛枝植原体tRNA-ipt基因完整序列进行PCR扩增和生物信息学分析。对泡桐丛枝植原体tRNA-ipt基因进行原核表达并制备抗体。利用Western blot和FITC间接免疫荧光显微镜检测其在植原体中的表达。使用分光光度计分析该基因对大肠杆菌生长的影响,用ELISA测定转化菌株细胞分裂素含量。【结果】首次发现泡桐丛枝、桑萎缩、长春花绿变及苦楝丛枝植原体中完整tRNA-ipt基因,大小为876 bp,编码291个氨基酸,且N端均含有ATP/GTP结合位点保守序列(GPTASGKT)。4种植原体tRNA-IPT之间的氨基酸序列相似率为99.1%-99.5%,与同组植原体同源性在95.4%-99.3%,与其他组植原体同源性低于70%。SDS-PAGE结果显示tRNA-IPT蛋白在大肠杆菌中得到表达。首次获得泡桐丛枝植原体tRNA-IPT抗体并检测到该蛋白在泡桐发病组织中的特异表达。经过对转化菌株生长曲线及玉米素含量的测定,发现该基因能促进大肠杆菌后期生长和玉米素核苷的积累。【结论】4种植原体tRNA-ipt基因编码相同特性的功能蛋白,泡桐丛枝植原体tRNA-IPT蛋白能够在植原体中表达,根据该基因对异源菌株生长速率和激素合成的影响推断该蛋白可能参与植原体的细胞分裂素合成,在致病过程中起到重要作用。 相似文献
945.
QIU Yang WANG ZhaoWei LIU YongXiang QI Nan SI Jie XIANG Xue XIA XiaoLing HU YuanYang ZHOU Xi 《中国科学:生命科学英文版》2013,56(8):711-714
Insects are a group of arthropods and the largest group of animals on Earth,with over one million species described to date.Like other life forms,insects suffer from viruses that cause disease and death.Viruses that are pathogenic to beneficial insects cause dramatic economic losses on agriculture.In contrast,viruses that are pathogenic to insect pests can be exploited as attractive biological control agents.All of these factors have led to an explosion in the amount of research into insect viruses in recent years,generating impressive quantities of information on the molecular and cellular biology of these viruses.Due to the wide variety of insect viruses,a better understanding of these viruses will expand our overall knowledge of their virology.Here,we review studies of several newly discovered RNA insect viruses in China. 相似文献
946.
Yi Huang Jianqing Zhou Huadan Ye Limin Xu Yanping Le Xi Yang Weifeng Xu Xiaoyan Huang Jiangfang Lian Shiwei Duan 《Gene》2013
The goal of our study is to evaluate the contribution of CXCL12 rs1746048 (hg19, chr10:44775574) to the risk of CHD in Han Chinese, and to summarize its role in CHD through meta-analysis of existing studies among various ethnic groups. Significant association is observed between rs1746048-C and an increased risk of CHD in Han Chinese (χ2 = 5.41, df = 1, P = 0.02). Post hoc analysis reveals an even stronger association of rs1746048 with the risk of CHD for subjects aged 65 years or older (genotype: χ2 = 8.39, df = 2, P = 0.015; allele: χ2 = 9.13, df = 1, P = 0.003, odd ratio (OR) = 1.91, 95% confidential interval (CI) = 1.25–2.91). A break down analysis by gender shows that rs1746048 is likely a CHD risk factor under the recessive model in males (CC + CT versus TT: P = 0.05, χ2 = 3.59, df = 1, OR = 1.72, 95% CI = 1.00–3.04). In addition, a meta-analysis of ten studies among over 107,000 individuals confirms that rs1746048 is a risk factor of CHD (P < 0.0001, OR = 1.12, 95% CI = 1.09–1.15) and this agrees with the findings of our case–control study in Han Chinese. 相似文献
947.
Objective
Myocyte enhancer factor-2A (MEF 2A) has been shown to be involved in atherosclerotic lesion development, but its role in preexisting lesions is still unclear. In the present study we aim to assess the role of MEF 2A in the progression of pre-existing atherosclerosis.Methods
Eighty apolipoprotein E-deficient mice (APOE KO) were randomly allocated to control, scramble and MEF 2A RNA interference (RNAi) groups, and constrictive collars were used to induce plaque formation. Six weeks after surgery, lentiviral shRNA construct was used to silence the expression of MEF 2A. Carotid plaques were harvested for analysis 4 weeks after viral vector transduction. Inflammatory gene expression in the plasma and carotid plaques was determined by using ELISAs and real-time RT-PCR.Results
The expression level of MEF 2A was significantly reduced in plasma and plaque in the RNAi group, compared to the control and NC groups, whereas the expression level of pro-inflammatory cytokines was markedly increased. Silencing MEF 2A using lentiviral shRNA significantly reduced the plaque collagen content and fibrous cap thickness, as well as increased plaque area. However, silencing MEF 2A had no obvious effect on plaque lipid content.Conclusions
Lentivirus-mediated MEF 2A shRNA accelerates inflammation and atherosclerosis in APOE KO mice, but has no effect on lipoprotein levels in plasma. 相似文献948.
949.
950.
Cotton (Gossypium hirsutum) 14‐3‐3 proteins participate in regulation of fibre initiation and elongation by modulating brassinosteroid signalling 下载免费PDF全文
Ying Zhou Ze‐Ting Zhang Mo Li Xin‐Zheng Wei Xiao‐Jie Li Bing‐Ying Li Xue‐Bao Li 《Plant biotechnology journal》2015,13(2):269-280
Cotton (Gossypium hirsutum) fibre is an important natural raw material for textile industry in the world. Understanding the molecular mechanism of fibre development is important for the development of future cotton varieties with superior fibre quality. In this study, overexpression of Gh14‐3‐3L in cotton promoted fibre elongation, leading to an increase in mature fibre length. In contrast, suppression of expression of Gh14‐3‐3L, Gh14‐3‐3e and Gh14‐3‐3h in cotton slowed down fibre initiation and elongation. As a result, the mature fibres of the Gh14‐3‐3 RNAi transgenic plants were significantly shorter than those of wild type. This ‘short fibre’ phenotype of the 14‐3‐3 RNAi cotton could be partially rescued by application of 2,4‐epibrassinolide (BL). Expression levels of the BR‐related and fibre‐related genes were altered in the Gh14‐3‐3 transgenic fibres. Furthermore, we identified Gh14‐3‐3 interacting proteins (including GhBZR1) in cotton. Site mutation assay revealed that Ser163 in GhBZR1 and Lys51/56/53 in Gh14‐3‐3L/e/h were required for Gh14‐3‐3‐GhBZR1 interaction. Nuclear localization of GhBZR1 protein was induced by BR, and phosphorylation of GhBZR1 by GhBIN2 kinase was helpful for its binding to Gh14‐3‐3 proteins. Additionally, 14‐3‐3‐regulated GhBZR1 protein may directly bind to GhXTH1 and GhEXP promoters to regulate gene expression for responding rapid fibre elongation. These results suggested that Gh14‐3‐3 proteins may be involved in regulating fibre initiation and elongation through their interacting with GhBZR1 to modulate BR signalling. Thus, our study provides the candidate intrinsic genes for improving fibre yield and quality by genetic manipulation. 相似文献