AIM:To investigate the in vitro killing effect of adenovirus-mediated herpes simplex virus thymidine kinase gene(HSV-TK) driven by hypoxic response element(HRE) on hepatoma cell line HepG2.METHODS:Recombinant adenoviral vector Ad-HRE-TK was constructed with HSV-TK under the control of HRE using AdEasy system.Then Ad-HRE-TK was transfected into hepatoma cell line HepG2 and the cells were cultured under normoxic or hypoxic conditions.After treated with GCV for 3 d,the sensitivity to GCV of HepG2 was measured by MTT method.RESULTS:Over 95% HepG2 cells infected with Ad-HRE-TK cultured under hypoxic condition were killed when the MOI was 100 and the concentration of GCV was 50 mg/L.On the contrary,no killing effect of GCV was observed in cells cultured under normoxic condition.CONCLUSION:HRE promotes the expression of HSV-TK specifically under hypoxic condition and induces the specific killing effect of GCV.

Non-O1/O139 group of Vibrio cholerae can cause human acute diarrhea disease,while compared with the O1 and O139 groups;it often ignore the risk of the disease for human being.Therefore,we analyzed the molecular characteristics of 31 V.cholerae isolated from Yunnan Province.We used the agar disc diffusion method (K-B) to carry out the antibiotic sensitivity test;polymerase chain reaction (PCR) amplification for the detection of virulence gene;at the same time,all of strains were performed for pulse field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).The drug sensitivity test showed that 67.74％ strains were resistant to rifampin,29.03％ resistant to nalidixic acid and cotrimoxazole,all of the isolates were sensitive to gentamicin and ciprofloxacin;PCR results showed that all strains had the ompW gene,87.10％ strains had hly gene,25.81％ strains had rstREl tor,16.13％ strains had rstRClassical and tcpAEl tor,while CT rfbO1 and rfbO139 gene were negative;PFGE results showed that 31 strains had a trend of discrete height,the same PFGE identity pattern was not nearly found;for the analysis of MLST,we found the one new alleles of gyrB,four new alleles of mdh gene,six new alleles of metE gene,two new alleles of pntA,three new alleles of purM and four new alleles of pyrC gene.After permutation and combination,we found 17 new ST types for V.cholerae(ST273-ST289).Non-O1/O139 group V.cholerae showed a high degree of diversity,while the non-O1/O139 group of V.cholerae in Yunnan Province has a certain geographical features,which enriched the existing molecular typing system of V.cholerae.

OBJECTIVE To investigate the improvement effects of Compound qinbai granules on ulcerative colitis （UC） in rats and its mechanism based on short-chain fatty acid （SCFA） and their targets G protein-coupled receptor （GPR）. METHODS Male SD rats were randomly divided into normal group （12 rats） and model group （30 rats）； the model group was given 5% dextran sulfate sodium solution to induce the UC model. Model rats were divided into the model group， positive control group [Mesalazine enteric-coated tablets 270 mg/（kg·d）] and Compound qinbai granules group [2.52 g/（kg·d）]， with 9 rats in each group. Rats in each group were orally administered with normal saline or corresponding medication twice a day， for three consecutive weeks. During intragastric administration， the general conditions of rats in each group were observed， and the disease activity index （DAI） scores were assessed after the last administration. Serum levels of pro-inflammatory cytokines （tumor necrosis factor-α， interleukin-6） and anti-inflammatory cytokines （transforming growth factor-β1， interleukin-10） were measured. Pathological changes in their colonic tissues were observed and scored. Additionally， the content of SCFA （acetic acid， propionic acid and butyric acid） in their feces as well as the protein and mRNA expressions of GPR41， GPR43 and GPR109A in colonic tissues were detected. RESULTS Compared with the normal group， rats in the model group exhibited lethargy and obvious blood in their feces； the colonic tissue structure was severely damaged， with pathological changes such as notable glandular loss， edema， and inflammatory cell infiltration visible； the serum levels of pro- inflammatory cytokines， DAI score and colonic pathology score were significantly increased， while the levels of anti-inflammatory cytokines， SCFA content， and protein and mRNA expressions of GPR41， GPR43 and GPR109A were significantly decreased or down-regulated （P＜0.01）. Compared with the model group， the general condition and pathological changes of colonic tissue in each administration group showed improvement， with significant reversal observed in the aforementioned quantitative indicators （P＜0.05 or P＜0.01）. CONCLUSIONS Compound qinbai granules can alleviate intestinal inflammation and intestinal mucosal damage in UC rats. These effects may be related to its ability to restore intestinal SCFA levels and the expression of their target GPR.