[目的]研究绞股蓝总皂苷(gypenosides,GPs)对RAW264.7细胞脂质累积及细胞内氯离子通道蛋白1(chloride intracellular channel 1,CLIC1)表达的影响,探讨GPs抗动脉粥样硬化的分子机制。[方法]将RAW264.7细胞接种于六孔板中,分为NC组、氧...[目的]研究绞股蓝总皂苷(gypenosides,GPs)对RAW264.7细胞脂质累积及细胞内氯离子通道蛋白1(chloride intracellular channel 1,CLIC1)表达的影响,探讨GPs抗动脉粥样硬化的分子机制。[方法]将RAW264.7细胞接种于六孔板中,分为NC组、氧化型低密度脂蛋白(oxidized low density lipoprotein,ox-LDL)组、GPs 10组、GPs 50组、GPs 100组及CLIC1 si RNA组。各组细胞处理24h后,油红O染色检测各组细胞内脂质的累积,化学法检测细胞内总胆固醇(total cholesterol,TC)及游离胆固醇(free cholesterol,FC)的含量,荧光定量PCR和免疫印迹法检测CLIC1、CD36m RNA和蛋白质的表达,免疫荧光技术观察CLIC1的细胞定位,并用MQAE法检测细胞内氯离子浓度的变化。[结果]与NC组相比,ox-LDL组CLIC1、CD36 m RNA(P<0.01,P<0.001)及蛋白(P<0.01,P<0.001)表达水平显著升高,细胞内TC(P<0.001)、FC(P<0.01)显著升高,细胞膜上CLIC1表达显著升高,细胞内氯离子浓度显著增加(P<0.01);经CLIC1 si RNA或GPs处理后,细胞内TC(P<0.001,P<0.001)、FC(P<0.01,P<0.01)含量降低,脂质累积减少,CLIC1、CD36 m RNA及蛋白表达水平显著下调(P<0.01,P<0.001)。[结论]CLIC1在巨噬细胞脂质累积中发挥着重要的作用,GPs可以通过调控CLIC1的表达抑制巨噬细胞脂质累积。展开更多
目的通过饥饿诱导人神经胶质瘤细胞发生自噬,利用siRNA技术部分沉默细胞内氯通道蛋白4(CLIC4),探讨CLIC4在细胞自噬中的作用。方法根据CLIC4的基因序列构建CLIC4siRNA质粒,建立稳定转染CLIC4siRNA的U251细胞株,分析CLIC4蛋白表达;MTT法...目的通过饥饿诱导人神经胶质瘤细胞发生自噬,利用siRNA技术部分沉默细胞内氯通道蛋白4(CLIC4),探讨CLIC4在细胞自噬中的作用。方法根据CLIC4的基因序列构建CLIC4siRNA质粒,建立稳定转染CLIC4siRNA的U251细胞株,分析CLIC4蛋白表达;MTT法检测转染pSH1Si-CLIC4对细胞生存率的影响;利用Western Blot检测转染CLIC4siRNA在U251细胞凋亡相关蛋白Bax、Bcl-2表达;检测饥饿条件下U251细胞LC3蛋白、Bax、Bcl-2的表达;检测抑制CLIC4表达对于饥饿条件下细胞白caspase-3和胞浆cytc以及LC3的表达。结果 Western Blot显示,与空质粒对照组相比,转染CLIC4siRNA的U251细胞CLIC4表达显著下降;与对照组相比,转染空质粒细胞组以及瞬时转染pSH1Si-CLIC4载体细胞组U251细胞生存率均无明显差异;单纯CLIC4siRNA对于U251细胞Bax、Bcl-2表达无影响;与对照组相比,饥饿8h能够诱导U251细胞自噬,LC3水平显著增加,而细胞Bax、Bcl-2表达无明显变化;转染CLIC4siRNA后饥饿8h,caspase-3、cytc以及LC3表达增加。结论单纯CLIC4siRNA对于U251细胞自噬和凋亡均无显著影响,饥饿条件下U251细胞发生自噬的同时并没有明显细胞凋亡过程,抑制CLIC4表达促进了饥饿条件下的U251细胞自噬,同时能够启动线粒体相关途径的细胞凋亡。展开更多
针对磁共振图像中存在的灰度不均匀问题,该文在灰度校正的连贯局部灰度聚类(coherent local intensity clustering,CLIC)模型的基础上,提出一种新的灰度校正算法.该算法通过引入图像边缘信息来更快寻找到组织边界,在CLIC模型中采用较大...针对磁共振图像中存在的灰度不均匀问题,该文在灰度校正的连贯局部灰度聚类(coherent local intensity clustering,CLIC)模型的基础上,提出一种新的灰度校正算法.该算法通过引入图像边缘信息来更快寻找到组织边界,在CLIC模型中采用较大的高斯窗函数以保证偏场的光滑性,并结合分裂布雷格曼迭代来加速算法.将改进后的算法用于处理模拟和真实的磁共振图像,实验结果表明,使用该算法能够获得比使用CLIC模型更好的效果.展开更多
Our research focused on the analy sis of concrete deterioration mechan ism under the coup ling effects of flexural load,cy clic wetting and dry ing, and sulfate. The relative dy namic modulus of elasticity of a corrod...Our research focused on the analy sis of concrete deterioration mechan ism under the coup ling effects of flexural load,cy clic wetting and dry ing, and sulfate. The relative dy namic modulus of elasticity of a corroded concrete samp le was tested, and scannin g electron microscop e was used to observe the microstructure of concrete under the coup ling effects of flexural load,cy clic wetting and dry ing, and sulf ate. Results manif ested that flexur al load and cy clic wetting and dry ing durin g the concrete service chan ged the corrosion p rocess of the sulfate mediu m in con crete and enh anced the deterioration of con crete p erforman ce.Furthermore, the influencin g p atterns of strength grade of concr ete, mass concentration of sulfate solution, and mineral admixtures on the degree of concrete deterioration were identified.展开更多
The ability to visualise proteins in their native environment and discern information regarding stoichiometry is of critical importance when studying protein interactions and function. We have used liquid cell atomic ...The ability to visualise proteins in their native environment and discern information regarding stoichiometry is of critical importance when studying protein interactions and function. We have used liquid cell atomic force microscopy (AFM) to visualise proteins in their native state in buffer and have determined their molecular volumes. The human proteins S100A8, S100A9, S100A12 and CLIC1 were used in this investigation. The effect of oxidation on the protein structure of CLIC1 was also investigated and we found that CLIC1 multimerisation could be discerned by AFM, which supports similar findings by other methods. We have found good correlation between the molecular volumes measured by AFM and the calculated volumes of the individual proteins. This method allows for the study of single soluble proteins under physiological conditions and could potentially be extended to study the structure of these proteins when located within a membrane environment.展开更多
The cryosphere is an integral part of the global climate system, however, many aspects of the cryosphere have not been fully covered within WCRP. Issues relating to potential changes in the climate cryosphere system b...The cryosphere is an integral part of the global climate system, however, many aspects of the cryosphere have not been fully covered within WCRP. Issues relating to potential changes in the climate cryosphere system become more and more important in order to describes research and coordination initiatives required to integrate fully studies of impact and response of the cryosphere to climate change. The article also indicates the recent progress of CliC, and its future plan.展开更多
文摘[目的]研究绞股蓝总皂苷(gypenosides,GPs)对RAW264.7细胞脂质累积及细胞内氯离子通道蛋白1(chloride intracellular channel 1,CLIC1)表达的影响,探讨GPs抗动脉粥样硬化的分子机制。[方法]将RAW264.7细胞接种于六孔板中,分为NC组、氧化型低密度脂蛋白(oxidized low density lipoprotein,ox-LDL)组、GPs 10组、GPs 50组、GPs 100组及CLIC1 si RNA组。各组细胞处理24h后,油红O染色检测各组细胞内脂质的累积,化学法检测细胞内总胆固醇(total cholesterol,TC)及游离胆固醇(free cholesterol,FC)的含量,荧光定量PCR和免疫印迹法检测CLIC1、CD36m RNA和蛋白质的表达,免疫荧光技术观察CLIC1的细胞定位,并用MQAE法检测细胞内氯离子浓度的变化。[结果]与NC组相比,ox-LDL组CLIC1、CD36 m RNA(P<0.01,P<0.001)及蛋白(P<0.01,P<0.001)表达水平显著升高,细胞内TC(P<0.001)、FC(P<0.01)显著升高,细胞膜上CLIC1表达显著升高,细胞内氯离子浓度显著增加(P<0.01);经CLIC1 si RNA或GPs处理后,细胞内TC(P<0.001,P<0.001)、FC(P<0.01,P<0.01)含量降低,脂质累积减少,CLIC1、CD36 m RNA及蛋白表达水平显著下调(P<0.01,P<0.001)。[结论]CLIC1在巨噬细胞脂质累积中发挥着重要的作用,GPs可以通过调控CLIC1的表达抑制巨噬细胞脂质累积。
文摘目的通过饥饿诱导人神经胶质瘤细胞发生自噬,利用siRNA技术部分沉默细胞内氯通道蛋白4(CLIC4),探讨CLIC4在细胞自噬中的作用。方法根据CLIC4的基因序列构建CLIC4siRNA质粒,建立稳定转染CLIC4siRNA的U251细胞株,分析CLIC4蛋白表达;MTT法检测转染pSH1Si-CLIC4对细胞生存率的影响;利用Western Blot检测转染CLIC4siRNA在U251细胞凋亡相关蛋白Bax、Bcl-2表达;检测饥饿条件下U251细胞LC3蛋白、Bax、Bcl-2的表达;检测抑制CLIC4表达对于饥饿条件下细胞白caspase-3和胞浆cytc以及LC3的表达。结果 Western Blot显示,与空质粒对照组相比,转染CLIC4siRNA的U251细胞CLIC4表达显著下降;与对照组相比,转染空质粒细胞组以及瞬时转染pSH1Si-CLIC4载体细胞组U251细胞生存率均无明显差异;单纯CLIC4siRNA对于U251细胞Bax、Bcl-2表达无影响;与对照组相比,饥饿8h能够诱导U251细胞自噬,LC3水平显著增加,而细胞Bax、Bcl-2表达无明显变化;转染CLIC4siRNA后饥饿8h,caspase-3、cytc以及LC3表达增加。结论单纯CLIC4siRNA对于U251细胞自噬和凋亡均无显著影响,饥饿条件下U251细胞发生自噬的同时并没有明显细胞凋亡过程,抑制CLIC4表达促进了饥饿条件下的U251细胞自噬,同时能够启动线粒体相关途径的细胞凋亡。
文摘针对磁共振图像中存在的灰度不均匀问题,该文在灰度校正的连贯局部灰度聚类(coherent local intensity clustering,CLIC)模型的基础上,提出一种新的灰度校正算法.该算法通过引入图像边缘信息来更快寻找到组织边界,在CLIC模型中采用较大的高斯窗函数以保证偏场的光滑性,并结合分裂布雷格曼迭代来加速算法.将改进后的算法用于处理模拟和真实的磁共振图像,实验结果表明,使用该算法能够获得比使用CLIC模型更好的效果.
基金Funded by Fujian Education Department(Nos.JA11329 and JA12412)Quanzhou(Fujian)Techno logy Research and Development Program(Nos.2013Z158,2013Z47,and 2010G7)
文摘Our research focused on the analy sis of concrete deterioration mechan ism under the coup ling effects of flexural load,cy clic wetting and dry ing, and sulfate. The relative dy namic modulus of elasticity of a corroded concrete samp le was tested, and scannin g electron microscop e was used to observe the microstructure of concrete under the coup ling effects of flexural load,cy clic wetting and dry ing, and sulf ate. Results manif ested that flexur al load and cy clic wetting and dry ing durin g the concrete service chan ged the corrosion p rocess of the sulfate mediu m in con crete and enh anced the deterioration of con crete p erforman ce.Furthermore, the influencin g p atterns of strength grade of concr ete, mass concentration of sulfate solution, and mineral admixtures on the degree of concrete deterioration were identified.
文摘The ability to visualise proteins in their native environment and discern information regarding stoichiometry is of critical importance when studying protein interactions and function. We have used liquid cell atomic force microscopy (AFM) to visualise proteins in their native state in buffer and have determined their molecular volumes. The human proteins S100A8, S100A9, S100A12 and CLIC1 were used in this investigation. The effect of oxidation on the protein structure of CLIC1 was also investigated and we found that CLIC1 multimerisation could be discerned by AFM, which supports similar findings by other methods. We have found good correlation between the molecular volumes measured by AFM and the calculated volumes of the individual proteins. This method allows for the study of single soluble proteins under physiological conditions and could potentially be extended to study the structure of these proteins when located within a membrane environment.
基金the National Natural Science Foundation of China(No.30470559,30330230,30240059)the National Basic Research Development Program(973)of China(No.2007CB512501)Beijing Natural Science Foundation(No.7052039)
文摘Dorsal root ganglion(DRG)neurons have peripheral terminals in skin,muscle,and other peripheral tissues,andcentral
文摘The cryosphere is an integral part of the global climate system, however, many aspects of the cryosphere have not been fully covered within WCRP. Issues relating to potential changes in the climate cryosphere system become more and more important in order to describes research and coordination initiatives required to integrate fully studies of impact and response of the cryosphere to climate change. The article also indicates the recent progress of CliC, and its future plan.
