综述——纳米材料与药物输递：基于介孔二氧化硅的多功能纳米药物输送体系研究进展

介孔二氧化硅因具有有序介孔结构、比表面积大、生物相容性好及表面易于修饰等特点, 在生物医药等领域显示出了极大的应用前景, 目前, 基于介孔二氧化硅的纳米药物输送体系已成为众多科研工作者研究的热点. 本文讨论了靶向修饰及成像等多功能化的介孔二氧化硅药物输送体系的研究进展, 同时详细介绍了一系列具有特定形态结构（如中空/摇铃状、纳米管等）的介孔二氧化硅基载药体系的制备、表面修饰及在其在药物输送、释放等领域的应用研究. 最后, 对目前介孔二氧化硅基药物输送体系（主要包括具有特定形态结构的介孔二氧化硅药物载体、多功能复合药物载体及可生物降解的介孔二氧化硅药物输送体系等）在实际应用中存在的问题进行了分析并对其未来的发展前景进行了展望.     

环状RNA在慢性病发病中作用机制的研究进展

环状RNA作为一种对基因表达进行精细调节的重要非编码RNA,不仅增加了非编码RNA介导的基因调控网络的复杂度,也加深了疾病发病机制研究的深度。虽然近年来环状RNA的功能研究有了长足的进步,确定了其作为ceRNA能够特异性吸附miRNA,解除相应miRNA对下游靶mRNA的抑制作用,此类研究也表明核外环状RNA介导的凋亡活化,增殖抑制和细胞与细胞间的交流在疾病发生发展过程中是至关重要的,但我们对环状RNA的了解还只是冰山一角,特别是病理状态下其作用的具体机制仍然需要我们不断探索。在此,本综述的主要目的是回顾目前关于环状RNA在心血管疾病、中枢神经系统疾病和癌症等慢性病领域的研究,探讨以上慢性病发病过程中环状RNA所起的作用以及展望未来环状RNA在疾病发病机制领域的研究。     

野油菜黄单胞菌原质体分泌黄原胶的电镜观察

经透射电镜观察首次发现野油菜黄单胞菌（Xanthomonas campestris）原生质体在以蔗糖为底物的高渗营养液中,能合成并分泌丝状黄原胶。     

采后ABA、GA_3对芒果细胞壁降解酶、类胡萝卜素含量的作用

芒果后熟初期上部和内部ＰＧ活性高于下部和外部。后熟期ＰＧ活性上升至高峰后下降,ＰＭＥ活性则不断下降。ＡＢＡ能使ＰＧ活性增高,ＧＡ３则抑制了ＰＧ活性,并推迟了ＰＧ活性的高峰期。不过,ＧＡ３或ＡＢＡ处理对后熟期ＰＭＥ活性都没有一致的影响。芒果后熟期α－胡萝卜素、α－胡萝卜素和叶黄素含量不断升高,ＧＡ３能使三者上升速度减缓;ＡＢＡ则显著加快β－胡萝卜素和叶黄素的上升。从外源β－胡萝卜素引起ＰＧ活性上升的结果,讨论了后熟期类胡萝卜素与ＰＧ活性的间接关系。     

Principal expression of two mRNA isoforms (ABCB 5alpha and ABCB 5beta ) of the ATP-binding cassette transporter gene ABCB 5 in melanoma cells and melanocytes

ATP-binding cassette (ABC) transporters play a pivotal role in physiology and pathology. We identified and cloned two novel mRNA isoforms (ABCB 5alpha and ABCB 5beta) of the ABC transporter ABCB 5 in human melanoma cells. The deduced ABCB 5alpha protein appears to be an altered splice variant containing only a putative ABC, whereas the ABCB 5beta isoform shares approximately 70% similarity with ABCB1 (MDR1) and has a deduced topological arrangement similar to that of the whole carboxyl terminal half of the ABCB1 gene product, P-glycoprotein, including an intact ABC. Northern blot, real-time PCR, and conventional RT-PCR were used to verify the expression profiles of ABCB 5alpha/beta. We found that the melanomas included among the NCI-60 panel of cell lines preferentially expressed both ABCB 5alpha and ABCB 5beta. However, ABCB 5alpha/beta expression was undetectable in two amelanotic melanomas (M14 and LOX-IMVI). The expression profile of ABCB 5alpha/beta in all of the other melanomas of the panel was confirmed both by RT-PCR and by sequencing. Neither ABCB 5alpha nor ABCB 5beta expression was found in normal tissues such as liver, spleen, thymus, kidney, lung, colon, small intestines or placenta. ABCB 5alpha/beta mRNAs were also expressed in normal melanocytes and in retinal pigment epithelial cells, suggesting that ABCB 5alpha/beta expression is pigment cell-specific and might be involved in melanogenesis. Our findings indicate that expression of ABCB 5alpha/beta might possibly provide two novel molecular markers for differential diagnosis of melanomas and constitute potential molecular targets for therapy of melanomas.     

基于低拷贝核基因GBBSI的禺毛茛复合体系统进化研究

禺毛茛多倍体复合体及其近缘种系统进化关系复杂,杂交与多倍化现象同时存在。该复合体内高倍性植物的形成及扩散过程仍需进一步研究。首次克隆了毛茛属植物低拷贝核基因颗粒结合型淀粉合成酶 I (GBBSI )基因,并利用其构建禺毛茛多倍体复合体及其近缘种的系统进化树和网状进化关系,进而证明其适合于研究毛茛属植物种下系统发育研究。结果表明：匍枝毛茛与多倍体复合体关系密切,参与了该多倍体复合体的起源和进化;禺毛茛起源于茴茴蒜和卷喙毛茛,扬子毛茛起源于茴茴蒜和匍枝毛茛;在该类群中茴茴蒜是个关键种,它在多倍体复合体中可能起着枢纽基因组的重要作用。     

前言：纳米生物医学: 一个交叉学科新前沿

当物质细微到纳米尺度,其性能会出现巨大的改变。基于纳米材料特殊性能的新技术已经成为世界各国高技术发展的前沿和热点。     

Covalent modification of stathmin by CCNU determined by FTMS analysis of modified proteins and tryptic peptides

Chemical modification of proteins is often carried out to generate protein-small molecule conjugates for various applications. The high resolution and mass accuracy of a Fourier transform mass spectrometer is particularly useful for assessing the extent or sites of covalent modifications. As protein-small molecule reactions often produce products with variable numbers of the compound incorporated at different sites, a direct mass analysis of the reaction products at times yields mass spectra hard to interpret. Chromatographic separation at protein level could reduce the complexity of a sample, thus allowing more accurate mass spectrometric analysis. In this report, we demonstrate the utility of reversed-phase protein chromatography and FT-ICR mass spectrometry in analyzing CCNU (lomustine, 1-(2-chloroethyl)-3-cyclohexyl-1-nitroso-urea, MW: 233.7 Da) modification of stathmin. With this combined approach, we determined the stoichiometry as well as sites of CCNU incorporation into the protein, demonstrating differential reactivity of several lysyl residues to CCNU alkylation.     

蹲起试验评价大学生心功能的效用研究

目的:探讨3种不同负荷蹲起试验方法对评价普通大学生心功能的效用.方法:采用60s60次蹲起、45s45次蹲起、30s30次蹲起3种不同运动负荷试验,测量和计算累积心功指数、即刻心功指数,并与VO2max作相关性分析.结果:60s60次蹲起测得的心功指数与VO2max的相关系数最高,45s45次蹲起的心功指数次之,30s30次最低;而3种不同负荷方法各自的即刻心功指数与VO2max的相关系数均高于累积心功指数.结论:60s60次蹲起试验评价心功能效度最高,30s30次最低;即刻心功指数比累积心功指数评价效度更高.