OBJECTIVE:To study the mechanism by which L-arginine regulates hypoxic pulmonary vascular structural remodeling.METHODS:Eighteen Wistar rats were randomly divided into control group,hypoxic group and hypoxic+L-arginine group.Pulmonary artery pressure was measured with right cardiac catheterization.Micro-structure and ultra-structure of pulmonary tissue were observed and collagen I expression was evaluated with immunohistochemistry.RESULTS:Mean pulmonary artery pressure(mPAP) was(2.7?0.3)kPa in hypoxic rats and(2.1?0.1)kPa in control rats(P

Objective: To investigate effect of exogenous wild-type p53 gene on the cell growth and tumorigenicity of human gallbladder cancer cell lines. Methods: After identification of the genetic status of p53 gene of GBC-SD cell lines with the immunocytochemistry staining and the direct sequencing technique of PCR products, eukaryotic expressing plasmid pCMV-p53 was introduced by lipofectamine-mediated into GBC-SD cell lines. Growing transfected cells were selected by G418. The presence and expression of exogenous p53 gene was detected by PCR, RT-PCR and Western blot. The cellular proliferating ability was assessed using the cell growth curve and cloning assay. The xenograft in nude mice was performed to examine the effect of tumorigenicity. Results: P53 protein overexpression was showed in GBC-SD cell lines. A transversion of TAC→AAC at codon 126 of exon 5 was confirmed. PCR, RT-PCR and Western blot showed exogenous p53 gene had successfully transfected into GBC-SD cells and obtained high expression. The growth and proliferation of the cells were greatly decreased, and the tumorigenicity was significantly inhibited after transfection wtp53. Conclusion: The expression of exogenous wild-type p53 gene could effectively inhibit the growth of gallbladder cancer GBC-SD cells in vitro and in vivo.

Objective:To investigate the different killing effects on human hilar cholangiocarinoma cells FRH with cytosine deaminase(CD) and herpes simplex virus thymidine kinase(HSV tk)double suicide genes coexpression compared with single gene mediated by retrovirus.To find a more efficient and low toxicity suicide gene therapy for hilar cholangiocarinoma.Methods:CD and HSV tk double suicide genes were transfected into PA317 cells using lipofectamine.The positive clones were picked out and cultured after G418 selected.The viral supernatant was collected.The FRH cells were infected with the virus containing the double suicide genes.After G418 selection,RT PCR was resorted to demonstrated the successful transcription of CD and HSV tk genes.The FRH/CD+tk and FRH cells in culture were respectively treated with 5 Fc and /or GCV.The cytoxicity efficacy was evaluated by microculture tetrajolium test (MTT) method.Results:The virus containing double suicide gene was produced in PA317 cells.Double suicide genes were stably expressed in RFH cells after being infected with the virus.The killing effect of combination 5 Fc with GCV on FRH/CD+tk cells is more effective than that of using 5 Fc or GCV alone.Conclusion:The CD+TK/5 Fc+GCV co expression system is more effective for killing effects on FRH cells than that of CD/5 Fc or tk/GCV system alone.