1.Research Advance in Recombinant Expression of Microbial Lipases
China Biotechnology 2006;0(05):-
Microbial lipases have been widely used in traditional industries,as well as in emerging biocatalysed areas owing to their ability to catalyze a variety of reactions in aqueous and non-aqueous media.Therefore,it is very important to enhance amount of lipase production by recombinant overexpression for meeting market demand.A critical review of main and novel strategies which have been employed for recombinant expression of microbial lipases are presented,including codon optimization,fusion and co-expression,dual expression system based on hybrid promoters,homologous overexpression,cell surface displaying and high-throughput screening based on gene library of expression.These new technologies are gradually coming to the forefront in the recombinant expression of lipase,especially for cell surface displaying and high-throughput screening based on gene library of expression.Meanwhile,several recombinant expressions for representative microbial lipases were also introduced and discussed,which are available for consultation when attempting to overexpress any lipases by scientists and industrialists.
2.Up-regulating effect of hepatitis C virus core protein on inducible nitric oxide synthase gene promoter
Feng-Jin GUO ; Jun CHENG ; Yan LIU ;
Chinese Journal of Infectious Diseases 1997;0(04):-
Objective To investigate the transactivating effect of hepatitis C virus(HCV)core protein on inducible nitric oxide synthase(iNOS)gene promoter and the molecular biological mecha- nisms of HCV pathogenesis.Methods Polymerase chain reaction(PCR)technique was employed to amplify the sequence of iNOS promoter by using HepG2 genomic DNA as template,and the product was cloned into pGEM-T vector.The iNOSp gene was cut from T-iNOSp by KpnⅠand XhoⅠ,and then was cloned into pCAT3-Basic,the constructed vector was named as pCAT3-iNOSp,pCAT3-iN- OSp was transfected into the LO_2 cell line.LO_2 cell was also cotransfected with pcDNA3.1(-)-core and pCAT3-iNOSp by FuGENE 6 transfection reagents.The LO_2 cells transfected with pCAT3-Basic was used as negative control.The activity of CAT in LO_2 cells was detected by an ELISA kit after 48 hours,which reflected the transactivating function of HCV core protein to iNOS gene promoter.Re- sults The expressive vector pcDNA3.1(-)-core and report vector pCAT3-iNOSp had been construc- ted and confirmed by restriction enzyme digestion and sequencing.The expression of CAT in LO_2 cells transfected with pCAT3-iNOSp and peDNA3,1(-)-core was 11 times as higher as that of pCAT3-bas- ic,and 6 times as higher as that of pCAT3-iNOSp.Conclusion It is suggested that HCV core protein can transactivate iNOS gene promoter.
3.Determination of Capsaicine, Dihydrocapsaicin, Imperatorin and Isoimperatorin in Guanjie Jietong Plas-ters by HPLC
China Pharmacist 2014;(11):1965-1967
Objective:To develop an HPLC method for the determination of capsaicine, dihydrocapsaicin, imperatorin and isoim-peratorin in Guanjie Jietong plasters. Methods:A CAPCELL PAK C18 column was used as the chromatographic column, and the flow rate was 0. 8 ml·min-1. The mobile phase A consisted of methanol-acetonitrile(1∶1), the mobile phase B was of 1% phosphoric acid. The detection wavelength was 280 nm and 254 nm, respectively. Results:There was a good linear relationship between the con-centrations and the peak areas within the range of 0. 298-5. 956μg(r=0. 9998) for capsaicine, 0. 152-3. 044μg(r=0. 999 6) for di-hydrocapsaicin, 0. 018-0. 352 μg(r=0. 999 5) for imperatorin and 0. 010-0. 204 μg(r=0. 999 3) for isoimperatorin. The average re-covery was 97. 8%(RSD=1. 02%), 97. 0%(RSD=0. 76%), 96. 6%(RSD=0. 65%) and 98. 1%(RSD=1. 35%), respectively. Conclusion:The method is convenient, accurate, sensitive and repeatable, which can be used in the determination of capsaicine, di-hydrocapsaicin, imperatorin and isoimperatorin in Guanjie Jietong plasters.
4.AZT inhibit telomerase activity of squamous cell carcinoma of tongue
China Oncology 2001;0(02):-
Purpose:To study the effect of inhibition of telomerase activity and cell cycle by transcriptase telomerase inhibitors (3′ azido 3′ deoxythymidine, AZT) on squamous cell carcinoma of tongue in vitro.Methods:Human squmous cell carcinoma of tongue cell line Tca8113 was used as target cell. Telomerase activity was determined by TRAP PCR ELISA in untreated and treated Tca8113 by AZT, cell cycle phases were analyzed by flow cytometry. Results:Telomerase activity of Tca8113 was significantly inhibited when treated with AZT, and the effect of inhibition was dose dependant (rate of telomerase activity treated with AZT in 0.3, 0.6, 1.0, 1.5mol 10 -1 was 0.69 0.03, 0.61 0.08, 0.53 0.11, 0.50 0.02 respectively, rate of telomerase activity treated without AZT was 0.76 0.06). Cell cycle of treated Tca8113 was changed with marked increase in G 2 /M phase compared with untreated Tca8113 (62.8% vs 19.7%, P
5.Optimization of Lipase Production Conditions by Geotrichum candidum Y162 Using Single Factor-response Surface Methodology
Jin-Yong YAN ; Jiang-Ke YANG ; Yun-Jun YAN ;
China Biotechnology 2006;0(08):-
The fermentation conditions of lipase production by Geotrichum candidum Y162 were optimized. Initially, the most suitable carbon olive oil, nitrogen source soybean flour and NH4Cl, salt BaCl2 and MgCl2 were selected according to single factorial experiments respectively. Based on the result, screening methodology Plackett-Burman design was used to evaluate the effects of twelve factors related to lipase production and three statistically significant factors olive oil, BaCl2 and NH4Cl were selected. The path of steepest ascent was used to approach the optimal region of lipase production subsequently. Then, the optimal combined concentration for maximum enzyme activity were further optimized by response surface methodology and determined as follows: olive oil 2.35%, BaCl2 0.36%,and NH4Cl 4.69%.The optimization of culture conditions of G.candidum Y162 led to a 2.25-fold increase in lipase production relative to initial result 14.16 U/ml, which indicate that single factor in combination with response surface methodology is an effective method for optimization of lipase production conditions by G.candidum Y162.
8.Diagnostic value of serum anti-mutated citrullinated vimentin antibodies in patients with rheumatoid arthritis: a Meta-analysis
Haixi YAN ; Linling CAI ; Gaobing JIN ; Jun LI
Chinese Journal of Laboratory Medicine 2014;37(8):603-607
Objective To assess the diagnostic value of anti-mutated citrullinated vimentin (MCV)antibody for rheumatoid arthritis (RA).Methods Meta analysis.The databases,including PubMed,The Excerpta Medica Database (Embase) and China National Knowledge Infrastructure (CNKI),from January 1990 to January 2013,were employed to search for the studies related to diagnostic value of anti-MCV for RA.The software Meta-Disc1.4 was used to perform Meta-analysis,investigate the sources of heterogeneity and draw the summary receiver operating characteristic (SROC) curve.The Begg's test was applied to evaluate the publication bias by use of Stata1 1 software.Results A total of 27 studies were included.Pooled sensitivity was 0.74[95% confidence interval (CI) 0.73 to 0.76] and pooled specificity was 0.83 [95% CI (0.82 to 0.85)].The area under the summary receiver operating characteristic curves was 0.896.Twenty-three literatures which detected both anti-MCV antibody and anti-cyclic citrullinated peptide(antikCCP) antibody show that:the area under curre of anti-MCV antibody and anti-CCP antibody were 0.887 and 0.924 respectively,but there was no significant difference (Z =1.525,P =0.064).Conclusions Results of the meta-analysis demonstrated that the MCV antibody may be a useful parameter in diagnosing RA as it shows high sensitivity and specificity.But there was no statistical difference between the results of anti-MCV antibody and anti-CCP antibody for the RA diagnosis.
9.Silence of Wnt5a gene inhibits migration and invasion of lung squamous carcinoma cells
Wei-Xing WANG ; Yan-Jun MAO ; Ji-Jin YANG ;
Academic Journal of Second Military Medical University 1985;0(06):-
Objective:To study the influence of Wnt5a gene silence on the proliferation,migration and invasion of lung squamous carcinoma cells.Methods:A recombinant plasmid pHI-siRNA~(Wnt5a-)was constructed and used to deliver small interference RNA (siRNA)targeting Wnt5a in SK-MES-1 cells;the transfected cells were screened to establish a stable transgenic cell line.MTT,cell cycle and Transwell assays were employed to evaluate the effect of Wnt5a gene silence on the proliferation,migration and invasion of lung squamous carcinoma cells.Results:Western blotting assay revealed that Wnt5a was lowly expressed in SK-MES-1~(Wnt5a-)(13.6%).The proliferation index(PI)of transgenic cell line was slightly lower than that of the control cell line([28.3?3.8]% vs[30.5?5.2]%). The migration and invasion capabilities of SK-MES-1~(Wnt5a-)cells were(47.3?9.2)% and(39.7?11.7)% of the control cells, respectively.Conclusion:Low Wnt5a expression can significantly inhibit the migration and invasion capabilities of SK-MES-1 cells, indicating that Wnt5a might be a potential target for gene therapy of lung squamous carcinoma.
10.Comparison of surface roughness and bacterial adhesion on zirconia ceramics and titanium alloys
Enlong JIN ; Yan-Jun JIAO ; Shu-Yun MENG ; Jue WANG ;
Chinese Journal of Tissue Engineering Research 2007;0(49):-
0.05).But the amount of adhered bacteria of surface-polished with titanium alloy is greater than that of surface-polished with zirconia ceramics(P