[Objective] This study aimed to increase the expression level of immun- odominant membrane protein gene (Imp) of phytoplasmas in E. coil BL21 (DE3). [Method] On the basis of orthogonal experiment, effects of diffe...[Objective] This study aimed to increase the expression level of immun- odominant membrane protein gene (Imp) of phytoplasmas in E. coil BL21 (DE3). [Method] On the basis of orthogonal experiment, effects of different culture conditions on recombinant bacteria E. coil BL21-pET-28a(+)-Imp were investigated. Based on the obtained optimal culture condition, effects of different induction conditions on the ex- pression level of Imp protein were explored. The expression level of Imp fusion pro- tein was analyzed by using SDS-PAGE and Gene Tools software. [Result] The re- sults showed that the optimal conditions for culture were at 37℃, pH 7.0, with liq- uid volume of 20% and oscillation speed of 200 r/min, for induction were at 37℃ for 6 h, with initial OD600 of about 1.5 and IPTG final concentration of 0.1 mmol/L. [Conclusion] The expression level of Imp achieved 70.98 mg/L under the optimal conditions. Optimized conditions for expression of Imp fusion protein in E. coil were determined.展开更多
Pulmonary embolism occurs more frequently after hepatectomy than previously thought but is infrequently associated with peripheral deep vein thrombosis. In this paper, we report 2 cases of postoperative hepatic vein t...Pulmonary embolism occurs more frequently after hepatectomy than previously thought but is infrequently associated with peripheral deep vein thrombosis. In this paper, we report 2 cases of postoperative hepatic vein thrombosis after liver resection. Both patients had undergone major hepatectomy of a non-cirrhotic liver largely exposing the middle hepatic vein. Clots were incidentally found in the middle hepatic vein 4 and 17 d after surgery despite routine systemic thrombo-prophylaxis with low molecular weight heparin. Coagulation of the transition plan in a context of mutation of the prothrombin gene and inflammation induced biloma were the likely predisposing conditions. Clots disappeared following curative anticoagulation. We conclude that thrombosis of hepatic veins may occur after liver resection and is a potential source of pulmonary embolism.展开更多
AIM: To determine the effect of hammerhead ribozyme targeting connective tissue growth factor (CCN2) on human hepatic stellate cell (HSC) function.METHODS: CCN2 hammerhead ribozyme cDNA plus two self-cleaving se...AIM: To determine the effect of hammerhead ribozyme targeting connective tissue growth factor (CCN2) on human hepatic stellate cell (HSC) function.METHODS: CCN2 hammerhead ribozyme cDNA plus two self-cleaving sequences were inserted into pTriEx2 to produce pTriCCN2-Rz. Each vector was individually transfected into cultured LX-2 human HSCs, which were then stimulated by addition of transforming growth factor (TGF)-β1 to the culture medium. Semiquantitative RT-PCR was used to determine mRNA levels for CCN2 or collagen I, while protein levels of each molecule in cell /ysates and conditioned medium were measured by ELISA. Cell-cycle progression of the transfected cells was assessed by flow cytometry.RESULTS: In pTriEx2-transfected LX-2 cells, TGF-β1 treatment caused an increase in the mRNA level for CCN2 or collagen I, and an increase in produced and secreted CCN2 or extracellular collagen I protein levels, pTriCCN2-Rz-transfected LX-2 cells showed decreased basal CCN2 or collagen mRNA levels, as well as produced and secreted CCN2 or collagen I protein. Furthermore, the TGF-β1-induced increase in mRNA or protein for CCN2 or collagen I was inhibited partially in pTriCCN2-Rz-transfected LX-2 cells. Inhibition of CCN2 using hammerhead ribozyme cDNA resulted in fewer of the cells transitioning into S phase.CONCLUSION: Endogenous CCN2 is a mediator of basal or TGF-β1-induced collagen I production in human HSCs and regulates entry of the cells into S phase.展开更多
基金Supported by Science and Technology Project of Shenzhen City (JC200903180710A)~~
文摘[Objective] This study aimed to increase the expression level of immun- odominant membrane protein gene (Imp) of phytoplasmas in E. coil BL21 (DE3). [Method] On the basis of orthogonal experiment, effects of different culture conditions on recombinant bacteria E. coil BL21-pET-28a(+)-Imp were investigated. Based on the obtained optimal culture condition, effects of different induction conditions on the ex- pression level of Imp protein were explored. The expression level of Imp fusion pro- tein was analyzed by using SDS-PAGE and Gene Tools software. [Result] The re- sults showed that the optimal conditions for culture were at 37℃, pH 7.0, with liq- uid volume of 20% and oscillation speed of 200 r/min, for induction were at 37℃ for 6 h, with initial OD600 of about 1.5 and IPTG final concentration of 0.1 mmol/L. [Conclusion] The expression level of Imp achieved 70.98 mg/L under the optimal conditions. Optimized conditions for expression of Imp fusion protein in E. coil were determined.
文摘Pulmonary embolism occurs more frequently after hepatectomy than previously thought but is infrequently associated with peripheral deep vein thrombosis. In this paper, we report 2 cases of postoperative hepatic vein thrombosis after liver resection. Both patients had undergone major hepatectomy of a non-cirrhotic liver largely exposing the middle hepatic vein. Clots were incidentally found in the middle hepatic vein 4 and 17 d after surgery despite routine systemic thrombo-prophylaxis with low molecular weight heparin. Coagulation of the transition plan in a context of mutation of the prothrombin gene and inflammation induced biloma were the likely predisposing conditions. Clots disappeared following curative anticoagulation. We conclude that thrombosis of hepatic veins may occur after liver resection and is a potential source of pulmonary embolism.
基金Supported by National Natural Scientific Foundation No.30872236 to Run-Ping Gao and NIH 5R01AA016003 to David R Brigstock
文摘AIM: To determine the effect of hammerhead ribozyme targeting connective tissue growth factor (CCN2) on human hepatic stellate cell (HSC) function.METHODS: CCN2 hammerhead ribozyme cDNA plus two self-cleaving sequences were inserted into pTriEx2 to produce pTriCCN2-Rz. Each vector was individually transfected into cultured LX-2 human HSCs, which were then stimulated by addition of transforming growth factor (TGF)-β1 to the culture medium. Semiquantitative RT-PCR was used to determine mRNA levels for CCN2 or collagen I, while protein levels of each molecule in cell /ysates and conditioned medium were measured by ELISA. Cell-cycle progression of the transfected cells was assessed by flow cytometry.RESULTS: In pTriEx2-transfected LX-2 cells, TGF-β1 treatment caused an increase in the mRNA level for CCN2 or collagen I, and an increase in produced and secreted CCN2 or extracellular collagen I protein levels, pTriCCN2-Rz-transfected LX-2 cells showed decreased basal CCN2 or collagen mRNA levels, as well as produced and secreted CCN2 or collagen I protein. Furthermore, the TGF-β1-induced increase in mRNA or protein for CCN2 or collagen I was inhibited partially in pTriCCN2-Rz-transfected LX-2 cells. Inhibition of CCN2 using hammerhead ribozyme cDNA resulted in fewer of the cells transitioning into S phase.CONCLUSION: Endogenous CCN2 is a mediator of basal or TGF-β1-induced collagen I production in human HSCs and regulates entry of the cells into S phase.