Blockade of L-type voltage-gated Ca channel inhibits ischemia-induced neurogenesis by down-regulating iNOS expression in adult mouse

Neurogenesis in the adult mammalian hippocampus may contribute to repairing the brain after injury. The signals that regulate neurogenesis in the dentate gyrus following ischemic stroke insult are not well known. We have previously reported that inducible nitric oxide synthase (iNOS) expression is necessary for ischemia-stimulated neurogenesis in the adult dentate gyrus. Here, we show that mice subjected to 90 min of middle cerebral artery occlusion (MCAO) significantly increased the number of new neurons and up-regulated iNOS expression in the dentate gyrus. Blockade of the L-type voltage-gated Ca(2+) channel (L-VGCC) prevented neurogenesis in the dentate gyrus and subventricular zone (SVZ), and down-regulated iNOS expression in the dentate gyrus after cerebral ischemia. This study suggests that Ca(2+) influx through L-VGCC is involved in ischemia-induced neurogenesis by up-regulating iNOS expression.     

逆转录病毒介导人VEGF在兔皮肤成纤维细胞中的表达

本文以人VEGFcDNA为目的基因,构建成逆转录病毒质粒载体,并进一步包装成重组缺陷型逆转录病毒,以此感染原代兔皮肤成纤维细胞,经G418筛选,获得了具有分泌VEGF能力的抗性细胞克隆,经Southern、PCR、Northern、RT-PCR等检测,证实了外源基因已整合至原代兔皮肤成纤维细胞基因组中,无重排和产生野生型病毒之患。整合的VEGF可在修饰细胞中转录,经内皮细胞增殖实验和血管通透性实验证实其表达产物具有强大的生物活性。为进一步研究VEGF的生物学功能和生理效应提供有用的工具。     

天然来源抗肿瘤化合物作用于MAPK通路的机制

天然来源抗肿瘤活性产物是抗肿瘤药物先导化合物的重要资源。促分裂原活化蛋白激酶(MAPK)通路是细胞内重要的信号转导系统,可以调节细胞的生长、凋亡、黏附、迁移等过程,继而影响肿瘤的发生、发展、侵袭、转移,是潜在的抗肿瘤药物作用靶点之一。本文将对天然来源化合物作用于MAPK信号通路的靶点分子及生物效应进行阐述,为肿瘤的化学预防及治疗提供启发。     

东乡野生稻根际可培养细菌多样性及其植物促生活性分析

为了解江西东乡野生稻(Oryza rufipogon)不同生育期根际可培养细菌群落多样性动态,从中寻找新的具有植物促生活性的微生物资源,分别于2009年5月、8月和11月采集了东乡野生稻秧苗期、抽穗期和成熟期根际土壤,采用稀释平板法分离到118株根际细菌,并检测了其植物促生活性.16S rRNA基因序列分析结合菌体形态...     

Establishing a dual knock-out cell line by lentivirus based combined CRISPR/Cas9 and Loxp/Cre system

The clustered regulatory interspersed short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system has been widely used for gene knock-out. Lentiviral vectors have been commonly used as a delivery method for this system, however, prolonged Cas9/sgRNA expression due to lentiviral integration can lead to accumulating off-target mutations. To solve this issue in engineering a gene knock-out cell line, this study established a novel system, which was composed of two lentiviral vectors. One lentiviral vector carried simultaneously sgRNAs and CRISPR/Cas9 expression cassettes targeting single or multiple gene(s); the other lentiviral vector carried Cre that could remove excess sgRNAs and Cas9 expression cassettes in the genome after gene targeting was achieved. To prove the principle, two candidate genes, extracellular matrix protein 1 (ECM1) and progranulin (PGRN), both highly expressed in MDA-MB-231 cells, were selected for testing the novel system. A dual knock-out of ECM1 and PGRN was successfully achieved in MDA-MB-231 cell line, with the sgRNAs and Cas9 expression cassettes being removed by Cre. This system should have great potential in applications for multiple genes knock-out in vitro.     

鼠肝中金属硫蛋白的纯化

旨在探索鼠肝中金属硫蛋白(MT)提取工艺并加以改进。按照经典方法工艺提取MT,用中空纤维柱超滤方法加以改进,依据MT自身特点进行分离和鉴定。结果显示,粗品符合MT特点:分子量在6.5kD左右;无280nm特征吸收峰,加酸后紫外吸收(200-300nm)肩峰消失;通过离子交换可以实现MT1、MT2的分离;通过原子吸收测定,含有锌、铜、镉3种金属,锌含量最高,具有重要的病理生理意义。因此,与其它方法比较,改进后方法更适宜实验室制备。     

节节麦-黑麦双二倍体种子贮藏蛋白的变异分析

利用SDS-PAGE和A-PAGE方法对获得的遗传稳定性逐年提高节节麦-黑麦双二倍体的麦谷蛋白和麦醇溶蛋白进行了分析.结果显示:在高分子量谷蛋白区域,双二倍体共检测到3条带,其中第1和第3条带与亲本节节麦的5t和10t亚基大小一致,中间的第2条带是两亲本都未出现的新麦谷蛋白条带,而黑麦的2r和6.5r亚基在双二倍体材料中未检测到;在低分子量谷蛋白区域,黑麦和节节麦分别有4条和2条带在双二倍体材料中未检测到.在醇溶蛋白的γ和β区,黑麦共有5条带在双二倍体材料中未检测到,在ω区,节节麦有1条带未检测到.研究表明,在双二倍体中两亲本控制贮藏蛋白的基因组之间发生了较大的改变,与亲本节节麦相比较,亲本黑麦控制的贮藏蛋白发生的改变更大;两亲本控制贮藏蛋白基因的遗传方式在双二倍体材料中表现为非加性效应.     

中药调节肠道菌群防治高血压的研究进展

肠道菌群是人体内环境的重要组成部分,可影响机体的代谢、免疫和炎症反应,与原发性高血压的发生发展密切相关,已成为防治高血压的研究热点。中药在临床用于原发性高血压的治疗且疗效显著。研究表明中药可被肠道菌群分解代谢为易于吸收的活性物质,而这些活性物质又可通过调节肠道菌群结构及其代谢产物防治高血压。本文以肠道菌群作为切入点,通过分析肠道菌群与原发性高血压发生发展的关系和中药在调节原发性高血压肠道菌群方面的研究,总结中药通过调节肠道菌群防治原发性高血压的作用和机制,以期为中药防治高血压及药物研发提供新的研究思路。     

The influence of colonizing methylobacteria on morphogenesis and resistance of sugar beet and white cabbage plants to <Emphasis Type="Italic">Erwinia carotovora</Emphasis>

The influence of colonization of sugar beet (Beta vulgaris var. saccharifera (Alef) Krass) and white cabbage (Brassica oleracea var. capitata L.) plants by methylotrophic bacteria Methylovorus mays on the growth, rooting, and plant resistance to phytopathogen bacteria Erwinia carotovora was investigated. The colonization by methylobacteria led to their steady association with the plants which had increased growth speed, root formation and photosynthetic activity. The colonized plants had increased resistance to Erwinia carotovora phytopathogen and were better adapted to greenhouse conditions. The obtained results showed the perspectives for the practical implementation of methylobacteria in the ecologically clean microbiology substances used as the plant growth stimulators and for the plant protection from pathogens.