不同恶化程度胃癌细胞系的细胞间隙连接通讯功能及Cx43表达的差异

以人正常胃黏膜上皮细胞系GES-1和不同恶化程度的人胃癌细胞系(低恶化AGS细胞系、中恶化SGC-7901细胞系、高恶化BGC-823细胞系)为研究对象,采用激光共聚焦显微镜的荧光漂白恢复技术及划痕标记荧光染料示踪技术研究不同恶化程度的胃癌细胞系细胞间隙连接通讯(Gap junctional intercellular communication,GJIC)功能的差异;采用荧光定量PCR技术和间接免疫荧光技术检测间隙连接蛋白(Connexin43,Cx43)基因在mRNA和蛋白水平的表达差异,探求其与胃癌恶性程度的相关性.结果表明,在正常胃细胞系和低、中及高恶化胃腺癌细胞系中,细胞间的GJIC功能随着恶性程度的升高而减弱(AGS、SGC-7901)或消失(BGC-823),且Cx43蛋白及mRNA的表达量随着恶性程度的升高而下调(AGS、SGC-7901)或缺失(BGC-823).这提示胃癌恶性程度与胃癌细胞的GJIC功能显著相关(P<0.05),GJIC在胃癌发生中起重要作用.     

Dynamics of proteins in Golgi membranes: comparisons between mammalian and plant cells highlighted by photobleaching techniques

In less than a decade the green fluorescent protein (GFP) has become one of the most popular tools for cell biologists for the study of dynamic processes in vivo. GFP has revolutionised the scientific approach for the study of vital organelles, such as the Golgi apparatus. As Golgi proteins can be tagged with GFP, in most cases without altering their targeting and function, it is a great substitute to conventional dyes used in the past to highlight this compartment. In this review, we cover the application of GFP and its spectral derivatives in the study of Golgi dynamics in mammalian and plant cells. In particular, we focus on the technique of selective photobleaching known as fluorescence recovery after photobleaching, which has successfully shed light on essential differences in the biology of the Golgi apparatus in mammalian and plant cells.     

光致变色和光致漂白材料的飞秒激光写/读实验研究

利用自行搭建的飞秒激光系统研究了光致变色材料二芳基乙烯和光致漂白材料二苯乙烯的写入及读出特性.通过分别改变激发能量和激发时间,对系统的存储分辨率进行了实验研究.结果表明,通过控制激发能量或激发时间都可以得到很高的存储分辨率;超低读出能量有利于信息存储寿命的提高;实现了三维光致变色存储密度达0.3×1010bits/cm3,光致漂白存储密度达0.5×1010bits/cm3.     

Photoinduced effects in amorphous semiconductor Ge(S, Se)2 chalcogenide films

The blue shift of optical transmittance edges were observed in amorphous semiconductor Ge(S, Se)2 chalcogenide films with light illumination. The shift in well-annealed films could be recovered by annealing the films near the glass-transition temperature again. The photocrystallization was also observed in amorphous Ge(S,Se)2 films with light illumination by the transmitting electron microscope measurement. The photoinduced phenomina of the amorphous Ge(S,Se)2 films could be applied to designing some new kinds of optical storage materials.     

Photoinduced effects in amorphous semiconductor Ge(S, Se)2 chalcogenide films

The blue shift of optical transmittance edges were observed in amorphous semiconductor Ge(S, Se)₂ chalcogenide films with light illumination. The shift in well-annealed films could be recovered by annealing the films near the glass-transition temperature again. The photocrystallization was also observed in amorphous Ge(S,Se)₂ films with light illumination by the transmitting electron microscope measurement. The photoinduced phenomina of the amorphous Ge(S,Se)₂ films could be applied to designing some new kinds of optical storage materials.     

活体细胞三维荧光图像恢复中的荧光衰减补偿

针对三维荧光显微镜成像中的光致漂白效应导致的图像质量下降问题，提出了一种荧光衰减曲线测量方法，并基于测量的荧光衰减曲线给出双指数曲线拟合，将拟合曲线用于活体细胞的三维荧光图像恢复．在此基础上给出期望最大化算法国像恢复结果，并对恢复结果做出分析．结果显示本文的方法可以对三维荧光显微成像中存在的荧光衰减进行有效补偿．     

Preparation of luminescent CdTe quantum dots doped core-shell nanoparticles and their application in cell recognition

Quantum dots (QDs), often referring to “semiconductor nanocrystals”, have gained increasing attention in the past decade due to their unique optical properties compared with conventional organic fluorophore[1]. In the fields of biochemistry, cell biology and molecular biology, water- soluble QDs have played many important roles[2 - 8]. However, luminescent QDs are usually prepared in or-ganic solvents and the products are not water soluble, which make them unsuitable for biological applica…