Objective To construct pcDNA 3.1(+)/HPV 18 E 6 fusion gene and a single-codon mutation pcDNA 3.1(+)/E6 F49R or pcDNA 3.1(+)/E6 F127R fusion gene in eukaryotic expression vector and study the effects on proliferation and apoptosis of cervical carcinoma cell line Hela. Method HPV 18 E6 gene sequence and the single-point mutation HPV 18 E6 F49R or HPV 18 E6 F127R were amplified from total RNA of Hela cell line by reverse transcription- polymerase chain reaction ( RT- PCR), then the gene sequences were respectively inserted into pcDNA 3.1(+) vector to reconstruct recombinant plasmids which were transfected transiently into Hela cells. MTT and RT-PCR were used to test the expression levels of HPV 18 E6 and the growth of HeLa cells after transfected about 48 h. The proliferation and apoptosis of Hela cells were detected respectively by cell counting and AO/EB fluorescent vital staining. Results The pcDNA 3.1(+)/HPV 18 E6, pcDNA 3.1(+)/E6 F49R and pcDNA 3.1(+)/E6 F127R eukaryotic expression vectors were successfully constructed. The gene of HPV 18 E6 was discriminably detected in the HeLa cells which were transfected with the recombinant plasmids. After several days, the proliferation of Hela cells transfected with pcDNA 3.1(+)/E6 F49R or pcDNA 3.1(+)/E6 F127R plasmid were obviously inhibited and the apoptotic rates were significantly increased, then the proliferation of cells transfected with pcDNA(+)/HPV 18 E6 was rather increased slightly, and we could observe the phenomena of early apoptosis and the formation of thekaryopyknosis by fluorescent microscope in the cells transfected with pcDNA 3.1(+)/E6 F49R or pcDNA 3.1(+)/E6 F127R. Conclusion The eukaryotic expressing vectors encoding HPV 18 E6 F49R and HPV 18 E6 F127R provide fundamental basis for the further study on HPV 18 E6 mechanism as well as prevention and treatment of uterine cancer.

Objective To study the diterpenoids possessed immunosuppressive activity from Tripterygium hypoglaucum. Methods The chemical constituents were isolated from the CHCl3 extracts of T. hypoglaucum by repeated column chromatography, including silica gel, Sephadex LH-20, and preparative HPLC. Their structures were elucidated on the basis of spectroscopic studies. The immunosuppressive activity of these compounds was tested using the lymphocyte transformation test. Results Compounds Ⅰ-Ⅵ were identified as triptobenzene H (Ⅰ), triptoquinone A (Ⅱ), triptoquinone B (Ⅲ), triptoquinone H (Ⅳ), triptonediol (Ⅴ), triptonoterpene (Ⅵ). Conclusion Compound Ⅰ-Ⅲ are isolated from this medicinal plant for the first time and all the compounds show the significant immunosuppressive activity.

Objective To understand the molecular characteristics of human-derived non-O157 Shiga toxin-producing Escherichia coil (STEC) strains circulating in five regions of China.Methods Twenty-seven non-O157 STEC strains isolated in five geographic regions were investigated by serotyping, stx1/stx2 subtyping and PCR screening for adhesion and other virulence genes.A multilocus sequence typing (MLST) scheme provided by E.coil MLST database were performed to amplify and sequence seven housekeeping genes (adk, icd, fumC, rgyrB, purA, mdh and recA) in those strains.Results Twenty-seven non-O157 STEC strains were typed into 16 O∶H serotypes.Among those strains, 11 harbored stx1a, 12 harbored stx1c, two harbored stx2e and the other three strains respectively harbored stx1a+stx2b, stx2d and stx2g.Positive rates of eae, efa1, saa, paa, toxB, astA and ehxA genes were 18.5%, 18.5%, 29.6%, 22.2%, 11.1%, 11.1% and 25.9%, respectively.The 27 strains were typed into 16 different sequence types (STs) based upon MLST.Conclusion Human-derived non-O157 STEC strains circulating in five regions of China are heterogeneous in their serotypes, stx1/stx2 subtypes and virulence gene profiles.

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