征服癌症的双刃刀--Rad51 D蛋白

人类Rad5l蛋白是同源重组的关键酶,发挥着链转移或链交换活性,启动DNA同源配对的作用。Rad51D蛋白是Rad51蛋白的5种同源物之一,对细胞调节有正反两种作用机制一方面作为辅助因子参与DNA修复同源重组,维持正常细胞周期;另一方面又是诱发癌症病变,防止癌细胞衰老的因素之一。Rad51D蛋白对细胞的作用机制,是人类征服癌症的双刃刀,如果阻止癌细胞的Rad51D蛋白作用可以促进癌细胞的死亡;而同时Rad51D蛋白作用的减弱将使细胞发生周期紊乱,产生新的病变。本文将近年来有关Rad51D的研究成果进行了整理,主要包括Rad51D蛋白的生物学特征和生物学功能两部分,同时对Rad51D蛋白的研究方向提出了自己的看法。     

Interleukin-10 Promoter Gene Polymorphisms and Susceptibility to Tuberculosis: A Meta-Analysis

Objective

As an update to other recent meta-analyses, the purpose of this study was to explore whether interleukin-10 (IL-10) polymorphisms and their haplotypes contribute to tuberculosis (TB) susceptibility.

Methods

We searched for published case-control studies examining IL-10 polymorphisms and TB in PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Wanfang databases and the Chinese National Knowledge Infrastructure (CNKI). Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the strengths of the associations.

Results

A total of 28 studies comprising 8,242 TB patients and 9,666 controls were included in the present study. There were no significant associations between the -1082G/A, -819C/T, and -592A/C polymorphisms and TB in the pooled samples. Subgroup analyses revealed that the -819T allele was associated with an increased TB risk in Asians in all genetic models (T vs. C: OR=1.17, 95% CI=1.05-1.29, P=0.003; TT vs. CC: OR=1.37, 95% CI=1.09-1.72, P=0.006; CT+TT vs. CC: OR=1.33, 95% CI=1.09-1.63, P=0.006; TT vs. CT+CC: OR=1.17, 95% CI=1.02-1.35, P=0.03) and that the -592A/C polymorphism was significantly associated with TB in Europeans under two genetic models (A vs. C: OR=0.77, 95% CI=0.60-0.98, P=0.03; AA vs. CC: OR=0.53, 95% CI=0.30-0.95, P=0.03). Furthermore, the GCC IL-10 promoter haplotype was associated with an increased risk of TB (GCC vs. others: P=1.42, 95% CI=1.02-1.97, P=0.04). Subgroup analyses based on ethnicity revealed that the GCC haplotype was associated with a higher risk of TB in Europeans, whereas the ACC haplotype was associated with a lower TB risk in both Asians and Europeans.

Conclusions

This meta-analysis suggests that the IL-10-819T/C polymorphism is associated with the risk of TB in Asians and that the IL-10-592A/C polymorphism may be a risk factor for TB in Europeans. Furthermore, these data indicate that IL-10 promoter haplotypes play a vital role in the susceptibility to or protection against the development of TB.     

Photosynthesis,Transpiration, and Water Use Efficiency in Two Divergent Leymus Chinensis Populations from Northeast China

The net photosynthetic rate (P _N), transpiration rate (E), and water use efficiency (WUE) of two divergent Leymus chinensis populations from the grassland region of Northeast China were compared. The two populations experienced the similar habitats, but differed in leaf colour, stomata numbers, and chlorophyll contents. The leaf P _N for the grey-green (GG) population was greater than that for the yellow-green (YG) population, while the leaf E for GG population was lower than that for the YG population. The greater WUE for the GG population suggests that this type is more able to maintain higher P _N under drought and is more fit for the rangeland use in this climate region.     

The effects of acylation stimulating protein supplementation <Emphasis Type="Italic">VS</Emphasis> antibody neutralization on energy expenditure in wildtype mice

Background  

Acylation stimulating protein (ASP) is an adipogenic hormone that stimulates triglyceride (TG) synthesis and glucose transport in adipocytes. Previous studies have shown that ASP-deficient C3 knockout mice are hyperphagic yet lean, as they display increased oxygen consumption and fatty acid oxidation compared to wildtype mice. In the present study, antibodies against ASP (Anti-ASP) and human recombinant ASP (rASP) were tested in vitro and in vivo. Continuous administration for 4 weeks via osmotic mini-pump of Anti-ASP or rASP was evaluated in wildtype mice on a high-fat diet (HFD) to examine their effects on body weight, food intake and energy expenditure.     

海马位置细胞研究进展

位置细胞是与动物行为活动所处位置密切相关并具有复杂锋电位的海马锥体细胞,是脑内认知地图的基本组成单元。当个体处于特定的“位置野”时,相应的位置细胞呈现最大放电。位置细胞并非单纯的感觉神经元,内、外源性信息输入均可影响位置细胞的放电活动,使位置野表现出一定的可塑性。本文对近年来关于海马位置细胞的发现、分布及其电生理特性等研究进行了综述。     

3D-pharmacophore model for RXRγ agonists

Three-dimensional pharmacophore models were generated for retinoid X receptor (RXR_γ) agonists using quantitative approach (CATALYST HypoRefine). One optimal pharmacophore model for selective RXR_γ agonists was determined through careful validation processes. The best quantitative model (Hypo-1) had five features and five excluded volumes: three hydrophobic aliphatic groups (HAL1, HAL2, and HAL3), one hydrophobic aromatic ring (HAR), and one hydrogen bond acceptor (HBA). The model was validated using a wide range of test molecules. It could predict agonist activity and identify highly potent molecules. The present results are valuable to discover and develop specific RXR_γ agonists with desired biological activities.