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.

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.

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.

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

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.

Adult ; Aged ; Humans ; Middle Aged ; Pneumoconiosis ; diagnostic imaging ; Radiography, Thoracic ; Retrospective Studies

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

Objective To explore the roles of urokinase type PA (uPA) and uPA receptor (uPA R) in the course of repair after human embryo corneal alkali burn in vitro . Methods After the alkali burn model in vitro was established successfully, some techniques such as the observation of cell culture and morphology, ICC and image analysis were used. Results No significant difference was found between the cells from corneal limbus and central cornea and almost all of them expressed AE1/AE3. The expressions of uPA and uPA R increased to the maximum at about 24 h after alkali burn. uPA expression distributed mainly in the cytoplasm but uPA R expression distributed mainly in the cell membrane. Conclusion The corneal epithelial cells of comparatively high purity can be acquired by tissue culture. There probably exists difference in development and vitality between embryo and adult cornea. There might be commonness of the roles of uPA and uPA R in epithelial tissue.

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.

To assess the impact of the operational simulation training system on the cultivation of ophthalmic students.
●METHODS: Four hundred and eighty ophthalmic students in China Medical University from 2009 to 2011 were chosen as objects and divided into two groups at random. The students in the experimental group used operation simulation training system combined with traditional teaching methods, while the students in the control group only used traditional teaching methods. We examined the operation skills and the confidence of all the students half a year later.
●RESULTS: The improvement of the operation skills during the suture technique examination, and the confidence for operation technology were significantly different in two groups. The basic skills of the students in the examination groups improved apparently during the operational simulation training and they were full of confidence to their operational technique.
●CONCLUSlON: The operational simulation training is useful for promoting the clinical ability for ophthalmic students and should be widely popularized.