NQO1 C609T polymorphism and esophageal cancer risk: a HuGE review and meta-analysis.

BACKGROUND: Many studies have been carried out to test the hypothesis that the NQO1 C609T polymorphism might be associated with the risk of esophageal cancer. However, the results are poorly consistent, partly due to genetic or other sources of heterogeneity. To investigate the association between this polymorphism and the risk of esophageal cancer, a meta-analysis was performed. METHODS: We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of association. The frequency of the putative risk allele in the controls was estimated by the inverse-variance method. Cochran's Q statistic and the inconsistency index (I2) were used to check heterogeneity. Egger's test and an inverted funnel plot were used to assess the publication bias. RESULTS: Our study included eight published case-control studies about the NQO1 C609T polymorphism and esophageal cancer, including a total of 1,217 esophageal cancer patients and 1,560 controls. Overall, a significant association was found between the NQO1 C609T variant and esophageal cancer under a recessive model (OR = 1.647; 95% CI = 1.233-2.200). Regarding histological type, more significant evidence was found for esophageal squamous cell carcinoma (ESCC) (OR = 2.03; 95% CI = 1.29-3.19) than esophageal adenocarcinoma (EAC) (OR = 1.61; 95% CI = 1.01-2.56) under a recessive model. CONCLUSIONS: The meta-analysis suggests that the NQO1 C609T polymorphism considerably increases the risk of esophageal cancer.

Prevalence of the metabolic syndrome among rural original adults in NingXia, China.

BACKGROUND: Metabolic syndrome (MS) is combination of medical disorders that increase people's risk for cardiovascular disease and diabetes mellitus. Little data exists on the prevalence of MS of rural original adults in Ningxia of China. METHODS: A cross-sectional survey method was used and the participants were interviewed by trained health workers under a structured questionnaire in rural of Ningxia in 2008. The number of research subjects was 1612. MS was defined by International Diabetes Federation IDF (2005). RESULTS: The age-adjusted prevalence of the metabolic syndrome was 11.8%, whereas ethnic-specific prevalence was 10.3% in Han ethnic group and 13.7% in Hui ethnic group. Components of MS and MS were more common in Hui ethnic group than Han ethnic group. The mean levels and prevalence of abnormal value increased with increasing age in both ethnic groups (Cochran-Artimage test for trend, Hui ethnic group P < 0.05, Han ethnic group P < 0.01). CONCLUSIONS: The prevalence of MS was high in rural residents' adults in Ningxia. Clustering of MS components and MS was increased with age. The components of MS have big differences among different ethnic groups.

Lipase diversity in glacier soil based on analysis of metagenomic DNA fragments and cell culture.

Lipase diversity in glacier soil was assessed by culture independent metagenomic DNA fragment screening and confirmed by cell culture experiments. A set of degenerate PCR primers specific for lipases of the hormone-sensitive lipase family was designed based on conserved motifs and used to directly PCR amplify metagenomic DNA from glacier soil. These products were used to construct a lipase fragment clone library. Among the 300 clones sequenced for the analysis, 201 clones encoding partial lipases shared 51-82%identity to known lipases in GenBank. Based on a phylogenetic analysis, five divergent clusters were established, one of which may represent a previously unidentified lipase subfamily. In the culture study, 11 lipase-producing bacteria were selectively isolated and characterized by 16S rDNA sequences. Using the above mentioned degenerate primers, seven lipase gene fragments were cloned, but not all of them could be accounted for by the clones in the library. Two full-length lipase genes obtained by TAIL-PCR were expressed in Pichia pastoris and characterized. Both were authentic lipases with optimum temperatures of

Functions of oligochitosan induced protein kinase in tobacco mosaic virus resistance and pathogenesis related proteins in tobacco.

Oligochitosan (OC) can regulate plant defense responses in many aspects, but the basic signal transduction pathway is still unclear. In this study, we used transgenic (TG) tobacco (Nicotiana Tabacum var. Samsun NN) as plant material whose oligochitosan induced protein kinase (OIPK) gene was inhibited by antisense transformation, to study the role of OIPK in tobacco defense reactions. The results showed that OIPK could increase tobacco resistance against tobacco mosaic virus (TMV), in that wild-type (WT) tobacco showed longer lesion appearance time, higher lesion inhibition ratio, smaller average final lesion diameter and lower average final lesion area percent to whole leaf area. It led us to analyze some pathogenesis related (PR) enzymes' activities and mRNA level, which played roles in tobacco resistance against TMV. We found that phenylalanine ammonia-lyase (PAL) and peroxidase (POD) activities were positively related to OIPK, but not polyphenol oxidase (PPO). It was also demonstrated that OIPK mRNA could be induced by OC, wound and TMV infection. In addition, OIPK could up-regulated three PR genes, PAL, chitinase (CHI) and beta-1, 3-glucanase (GLU) mRNA level to different extent. Taken together, these results implied that OIPK could function in tobacco resistance against both biotic and abiotic stress, possibly via various PR proteins.

Preparation of raspberry-like polymer/silica nanocomposite microspheres via emulsifier-free polymerization in water/acetone media.

Raspberry-like polymer/silica nanocomposite microspheres were prepared by emulsifier-free copolymerization of styrene (St) with butyl acrylate (BA) in the presence of 20 nm silica nanoparticles in water/acetone media. A cationic monomer, 2-(methacryloyl)ethyltrimethylammonium chloride (MTC), was used as comonomer and nanosilica particles were adsorbed onto the growing latex core via the electrostatic interaction between negatively charged silica particles and positively charged polymer particles. The average particle sizes and the final silica contents of the nanocomposite microspheres ranged from 200 to 500 nm and 20 to 40 wt%, respectively, depending on the reaction conditions. The solid content of the obtained dispersions could be adjusted between 10 and 25 wt%. The influence of some synthetic parameters, for instance, the ratio of acetone/water, initial silica amount, the mass ratio of the St/BA, MTC, and the APS concentration on the polymerization stability, the average particle size, silica content, and morphology of the composite microspheres, were studied here in detail. It was found that the addition of acetone to the continuous phase resulted in smaller particle sizes and for the lower dielectric medium electrostatic repulsion becomes larger; hence coagulative nucleation is reduced compared to that in aqueous media.