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941.
942.
Zhenkun Li Xueyun Huo Shuangyue Zhang Jing Lu Changlong Li Meng Guo Rui Fu Zhengming He Xiaoyan Du Zhenwen Chen 《PloS one》2015,10(5)
Deformities in the Circle of Willis (CoW) can significantly increase the risk of cerebrovascular disease in humans. However, the molecular mechanisms underlying these deformities have not been understood. Based on our previous studies, variations in the CoW of gerbils are hereditary. A normal CoW is observed in approximately 60% of gerbils, a percentage that also applies to humans. Thus, gerbil is an ideal experimental model for studying variations in the CoW. To study the mechanisms underlying these variations, we selected genes associated with different types of the CoW using suppression subtractive hybridization (SSH). After evaluating the efficiency of SSH using quantitative real-time polymerase chain reaction (qPCR) on subtracted and unsubtracted cDNA and Southern blotting on SSH PCR products, 12 SSH libraries were established. We identified 4 genes (CST3, GNAS, GPx4 and PFN2) associated with variations in the CoW. These genes were identified with qPCR and Western blotting using 70 expressed sequence tags from the SSH libraries. Cloning and sequencing allowed us to demonstrate that the 4 genes were closely related to mouse genes. We may assume that these 4 genes play an important role in the development of variations in the CoW. This study provides a foundation for further research of genes related to development of variations in the CoW and the mechanisms of dysmorphosis of cerebral vessels. 相似文献
943.
944.
Jing Zhang Qiu-Sha Pan Xing-Kai Qian Xiang-Lu Zhou Ya-Jie Wang Rong-Jing He Le-Tian Wang Yan-Ran Li Hong Huo Cheng-Gong Sun Lei Sun Li-Wei Zou Ling Yang 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):629
Pancreatic lipase (PL) is a well-known key target for the prevention and treatment of obesity. Human carboxylesterase 1A (hCES1A) has become an important target for the treatment of hyperlipidaemia. Thus, the discovery of potent dual-target inhibitors based on PL and hCES1A hold great potential for the development of remedies for treating related metabolic diseases. In this study, a series of natural triterpenoids were collected and the inhibitory effects of these triterpenoids on PL and hCES1A were determined using fluorescence-based biochemical assays. It was found that oleanolic acid (OA) and ursolic acid (UA) have the excellent inhibitory effects against PL and hCES1A, and highly selectivity over hCES2A. Subsequently, a number of compounds based on the OA and UA skeletons were synthesised and evaluated. Structure–activity relationship (SAR) analysis of these compounds revealed that the acetyl group at the C-3 site of UA (compound 41) was very essential for both PL and hCES1A inhibition, with IC50 of 0.75 µM and 0.014 µM, respectively. In addition, compound 39 with 2-enol and 3-ketal moiety of OA also has strong inhibitory effects against both PL and hCES1A, with IC50 of 2.13 µM and 0.055 µM, respectively. Furthermore, compound 39 and 41 exhibited good selectivity over other human serine hydrolases including hCES2A, butyrylcholinesterase (BChE) and dipeptidyl peptidase IV (DPP-IV). Inhibitory kinetics and molecular docking studies demonstrated that both compounds 39 and 41 were effective mixed inhibitors of PL, while competitive inhibitors of hCES1A. Further investigations demonstrated that both compounds 39 and 41 could inhibit adipocyte adipogenesis induced by mouse preadipocytes. Collectively, we found two triterpenoid derivatives with strong inhibitory ability on both PL and hCES1A, which can be served as promising lead compounds for the development of more potent dual-target inhibitors targeting on PL and hCES1A. 相似文献
945.
A组轮状病毒我国地方株VP6基因的序列测定及其在杆状病毒系统中的表达 总被引:5,自引:0,他引:5
通过反转录- 聚合酶链反应( R T- P C R) 获得了轮状病毒地方株 T114 V P6 全基因的c D N A 片段,将其克隆入转移载体质粒p V L1393 中,构建成重组质粒p V L1393 - V P6 。对克隆的 V P6 基因进行序列测定,并用它和杆状病毒( Ac M N P V) 野毒株 D N A 共转染 Sf9 细胞,筛选纯化得到含 V P6 基因插入片段的重组杆状病毒,并进行了表达重组蛋白 V P6 的检测。测序结果显示 V P6 基因全长1 356bp ,序列分析显示与 Wa 株非常接近,提示 T114 为亚组Ⅱ病毒株。用高价免疫血清经 Western blot 检测表达产物,结果显示,重组病毒感染细胞裂解液样品中可见大小约45k D 的特异条带;亚组Ⅱ特异性单抗检测到大小约120k D 的条带,提示重组蛋白 V P6 获得了表达,具有正常的抗原反应性和天然 V P6 的三体结构。 相似文献
946.
共聚焦镜观察凋亡巨噬细胞内pH的变化 总被引:3,自引:0,他引:3
用透射电镜观察巨噬细胞的形态学改变,结果显示,地塞米松处理8小时后,大部分巨噬细胞发生凋亡特征变化:胞突缩短、减少,胞膜完整。胞体皱缩,胞质密度增加,其中出现大量空泡。胞核染色质边聚、浓缩。另外用激光扫描共聚焦显微镜(ACAS570)和pH荧光探针SNARF┐1/AM实时检测地塞米松处理巨噬细胞胞浆pH的动态变化。加入地塞米松,多数巨噬细胞胞浆马上发生快速和短期的碱化。随后,胞浆pH缓慢降低,胞浆酸化。结果表明,胞浆酸化是细胞凋亡发展的必然过程,胞浆碱化则很可能与细胞凋亡的发生相关,也可能与细胞种类、细胞功能状态相关 相似文献
947.
Brittany E. Jewell An Xu Dandan Zhu Mo-Fan Huang Linchao Lu Mo Liu Erica L. Underwood Jun Hyoung Park Huihui Fan Julian A. Gingold Ruoji Zhou Jian Tu Zijun Huo Ying Liu Weidong Jin Yi-Hung Chen Yitian Xu Shu-Hsia Chen Nino Rainusso Nathaniel K. Berg Danielle A. Bazer Christopher Vellano Philip Jones Holger K. Eltzschig Zhongming Zhao Benny Abraham Kaipparettu Ruiying Zhao Lisa L. Wang Dung-Fang Lee 《PLoS genetics》2021,17(12)
948.
Photocatalytic CO2 reduction to hydrocarbon fuels through solar energy provides a feasible channel for reducing CO2 emission and resource depletion. Nevertheless, severe charge recombination and high energy barrier limit the CO2 reduction efficiency. Herein, a surface amine-functionalized SnO2 with oxygen vacancies (A-Vo-SnO2) is fabricated to achieve visible-light-driven photocatalytic CO2 reduction. Specifically, amino groups modified onto the surface of the catalyst can provide more active sites to promote the adsorption of CO2. Meanwhile, the synchronously induced oxygen defect level reduces the band-gap energy and expands the light-absorption region from UV light to visible light. The oxygen vacancies can modulate the electronic structure and work as the separation centers of spatial charges, thus promoting the interfacial charge transfer efficiency and providing more catalytic sites, as evidenced by experimental observation and theoretical calculation. As expected, this A-Vo-SnO2 exhibits a CH4 evolution rate of 17.27 µmol g−1 h−1 without adding sacrificial agent and co-catalyst, much higher than 5.98 µmol g−1 h−1 of pure SnO2. This work can provide significant inspiration for the design of defect engineering based on visible-light-driven photocatalysts towards photocatalytic CO2 conversion. 相似文献
949.
Siguang Guo Zhefei Sun Yu Liu Xinbo Guo Haoqin Feng Shi Luo Changhao Wei Yang Zheng Xuming Zhang Kangwoon Kim Haodong Liu Paul K Chu Biao Gao Qiaobao Zhang Kaifu Huo 《Liver Transplantation》2024,14(13):2303876
The manipulation of stress in high-capacity microscale alloying anode materials, which undergo significant volumetric variation during cycling, is crucial prerequisite for improved their cycling capability. In this work, an innovative structural design strategy is proposed for scalable fabrication of a unique 3D highly porous micro structured germanium (Ge) featuring micro-nano hierarchical architecture as viable anode for high-performance lithium-ion batteries (LIBs). The resultant micro-sized Ge, consisting of interconnected nanoligaments and bicontinuous nanopores, is endowed with high activity, decreased Li+ diffusion distance and alleviated volume variation, appealing as an ideal platform for in-depth understanding the relationship between structural design and stress evolution. Such a micro-sized Ge being highly porous delivers a record high initial Coulombic efficiency of 92.5%, large volumetric capacity of 2,421 mAh cm−3 at 1.2 mA cm−2, exceptional rate capability (805.6 mAh g−1 at 10 Ag−1) and cycling stability (over 90% capacity retention after 1000 cycles even at 5 A g−1), largely outperforming the reported Ge-based anodes for LIBs. Furthermore, its underlying Li storage mechanism and stress dispersion behavior are explicitly revealed by combined substantial in situ/ex situ experimental characterizations and theoretical computation. This work provides novel insights into the rational design of high-performance and durable alloying anodes toward high-energy LIBs. 相似文献
950.
Yuan-Ling Yu Meng-Ting Zhang Yan Huo Ji-Liang Tang Qing Liu Xiao-Ying Chen Rong-Xiang Fang Li-Li Zhang 《Insect Science》2021,28(2):315-329
Rice stripe virus(RSV)is the causative agent of rice stripe disease and is completely dependent on insect vectors for its plant-to-plant transmission.Laodelphax striatellus is the major insect vector for RSV.In this study,we explored the interactions be-tween RSV infection and L.striatellus autophagy,a potential intrinsic antiviral mechanism in insects.We found that L.striatellus autophagic activity did not affect RSV infection;however,the autophagy related-8(Atg8)gene significantly enhanced virus infection.Dur-ing RSV initial infection within the L.striatellus midgut,silencing of Atg8 expression significantly decreased the phosphorylation of c-Jun N-terminal kinase(p-JNK);however,when RSV infection is absent,silencing of Atg8 did not alter p-JNK levels.Thesc results indicated that Atg8 might activate the JNK machinery by allowing more virus infection into cells.We further revealed that Atg8-deficiency significantly decreased RSV accumu-lation on the surface of the insect midgut epithelial cells,suggesting a receptor trafficking function of the y-aminobutyric acid receptor-associated protein family.Using the RSV ovary entry as a model,in which vitellogenin receptor(V gR)mediates RSV cell entry,we clarified that Atg8-deficiency decreased the abundance of V gR localizing on the cytomem-brane and disturbed the attachment of RSV in the germarium zones.Collectively,these results revealed an autophagy-independent function of L.striatellus Atg8 that enhances RSV initial infection by increasing virus attachment on the infection sites. 相似文献