Influencing factors and population attributable risk percent of low back pain in automobile assemblers / 中国职业医学

Objective: To investigate the influencing factors and population attributable risk percent (PAR%) of low back pain in automobile assemblers. Methods: A total of 634 assemblers from 11 automobile manufacturers in Shiyan City, Hubei Province were chosen as research subjects using judgment sampling method. The prevalence of low back pain in the past one year was investigated using Musculoskeletal Disorders Questionnaire. PAR% was used to analyze the contribution of influencing factors to low back pain. Results: The annual prevalence of low back pain was 68.8%. The results of multivariate logistics regression showed that length of service>15 years, high school or secondary college education or above, standing most of the time, sitting most of the time, the proportion of cumulative time of poor posture in work shift time ≥1/8, and bending for insufficient height of working space were the risk factors for low back pain (all P<0.05). The PAR% of the proportion of cumulative time of poor posture in work shift time ≥1/8 was 43.0%, 37.8% for standing most of the time, and 12.8% for bending for insufficient height of working space. Conclusion: The annual prevalence of low back pain was higher in automobile assemblers. The influencing factors included individual factors and occupational factors. The proportion of cumulative time of poor posture in work shift time ≥1/8, standing most of the time and bending for insufficient height of working space should be taken as the priority intervention factors to reduce the prevalence of low back pain among assemblers in this enterprise.

Study on the effects of noise on hypertension and hyperglycemia among occupational workers / 中华劳动卫生职业病杂志

Objective@#To study the effect of noise on hypertension and hyperglycemia among occupational workers.@*Methods@#Total 670 workers in an automobile manufacturing company were selected as the subjects of physical examination in 2017. According to the noise exposure or not, the subjects were divided into control group (no noise exposure) 143 and contact group (noise exposure) 527. Questionnaire survey and physical examination were conducted. The measurement data were analyzed by t-test, and the count data and grade data were analyzed by χ2 test. The influence of noise on blood glucose, heart rate, blood pressure and other indicators was analyzed by logistic regression, and the OR and 95%CI of each risk factor were calculated.@*Results@#The average age of the control group and the contact group was no significant difference (P>0.05) . There were 139 (20.7%) cases of high systolic pressure, 154 (23.0%) cases of high diastolic pressure, 63 (9.4%) cases of hyperglycemia, 29 (4.3%) cases of tachycardia. Compared with the control group, there were significant differences in systolic blood pressure, diastolic blood pressure and blood glucose in the contact group (P<0.05) . Compared with the control group, the systolic blood pressure, diastolic blood pressure and blood glucose of the subjects in the corresponding age contact group increased significantly (P<0.05) . The years of noise exposure were protective factors for systolic and diastolic blood pressure (OR=0.970, 0.973) .@*Conclusion@#Noise exposure may increase blood pressure and blood sugar of occupational workers, but the effect on heart rate can not be determined.

Analysis of work-related low back musculoskeletal disorders among electric welders in an automobile factory / 中国职业医学

OBJECTIVE: To explore the prevalence of work-related low back musculoskeletal disorders(WMSDs) among electric welders in an automobile factory and to analyze its individual influence factors. METHODS: A total of 754 electric welders with a service length ≥1.0 years from an automobile factory in Shiyan City were selected using judgment sampling method. The Musculoskeletal Disorders Standard Questionnaire was used to collect the information of low back WMSDs. RESULTS: The annual prevalence of low back WMSDs among electric welders was 65.9%(497/754). The prevalence in females was higher than that in males(78.4% vs 63.1%, P<0.01). The prevalence of WMSDs had a rising tendency with age, educational level and service length(P<0.01). The multivariate logistic regression analysis results showed that the risk factors for low back WMSDs were age, gender, and educational level(P<0.05).CONCLUSION: The prevalence of low back WMSDs of electric welders in the automobile factory is high. Gender, age and educational level are the main risk factors affecting low back WMSDs.

Prokaryotic expression and purification of SET7 with GST-tag / 军事医学

Objective To purify and prokaryotically express the histone methyltransferase SET7.Methods The coding sequence of full length SET7 was amplified from breast library by PCR and cloned into the pGEX-KG vector.The correct recombinant plasmid was introduced into E.coli.The expressed protein was identified by SDS-PAGE.Results DNA sequencing indicated the SET7 was constructed.GST-SET7 fusion protein was identified by SDS-PAGE.Conclusion The prokaryotically expressed protein of GST-SET7 is obtained,which will falilitate further study of SET7 function.

Lentivirus-mediated knockdown of human E6 AP inhibits gastric cancer cell prolifera-tion and migration / 军事医学

Objective To detect the effect of E6AP on gastric cancer cell proliferation and migration.Methods The expression of E6AP in different gastric cancer cell lines and normal gastric mucosa epithelial cell lines was detected by Western blotting.Gastric cancer cells BGC-823 stably expressing E6AP short hairpan RNA(shRNA) were obtained by lentiviral vector of E6AP.The effect of E6AP on BGC-823 cell growth and migration was determined by CCK-8 kit, Tran-swell and wound healing assay.Results Gastric cancer cell line BGC-823 in which E6AP was stably knocked down was established.Knockdown of E6AP inhibited the proliferation and migration of BGC-823 cells.Conclusion E6AP plays a key role in gastric cancer proliferation and migration.

Construction and functional characterization of alentiviralvector mediating RNA interference of DEK gene / 军事医学

Objective To construct the lentiviral vector of RNA interference(RNAi) for DEK,and to detect its effect on breast cancer cell growth.Methods The DEK siRNA was designed and constructed based on DEK sequence using a lentiviral vector.The lentivirul vector containing DEK siRNA was named PSIH-H1-DEK as confirmed by PCR and sequenceing.PSIH-H1-DEK was then packaged with accessory plasmids into lentivirus in 293T cells and selected for 2 weeks with puromycin ( puro ) before the mixed colonies stably expressing DEK siRNA were obtained and the DEK expression was detected by real time PCR( RT-PCR) and Western blotting.The effect of DEK siRNA on ZR75-1 cell growth was determined by cell counting kit.Results Western blot and RT-PCR showed that PSIH-H1-DEK siRNA could suppress DEK gene expression.Suppression of DEK could markedly inhibit the growth of ZR75-1 cells.Conclusion The lentivirus-mediated DEK siRNA is obtained,which will facilitate further research on DEK function in breast cancer development.

Lentiviral vector for E6AP small-interfering RNA and its effect on breast cancer growth / 军事医学

Objective To construct the lentiviral vector (pSIH-H1) for E6AP small-interfering RNA(siRNA) and to detect its effect on breast cancer ZR 75-1cell growth.Methods E6AP siRNA was designed and constructed based on hu-man papillomavirus E6-associated protein ( E6AP) cDNA sequence.The expression of E6AP was examined by real-time quantitative PCR(qRT-PCR) and Western blotting.The effect of E6AP on ZR75-1 cell growth was determined by cck-8 kit.Results DNA sequencing indicated that E 6AP siRNA expression vector was constructed successfully .qRT-PCR and Western blotting experiments showed that pSIH-H1-E6AP siRNA could suppress the E6AP gene expression.Suppression of E6AP could markedly inhibit the growth of ZR 75-1.Conclusion A lentivirus RNA interference ( RNAi) vector targeting E6AP gene is successfully constructed ,which inhibits the cell growth of ZR 75-1.

Construction and activity characterization of E-cadherin and N-cadherin promoters / 军事医学

Objective To clone E-cadherin and N-cadherin promoters and insert them into a luciferase reporter gene vector, and to characterize the promoter activity of E-cadherin and N-cadherin.Methods E-cadherin and N-cadherin pro-moter were cloned into pGL 4-basic.The resulting plasmids were determined by DNA sequencing .The promoter activity was analyzed in breast cancer cell line ZR 75-1 and hepatocarcinoma cell line HepG 2.Results DNA sequencing showed that the sequences of the cloned promoter regions were correct .Analysis of the reporter gene activity indicated that the E-cad-herin and N-cadherin promoters had the highest transcriptional activity in ZR 75-1 and HepG2 cells.Conclusion The E-cadherin and N-cadherin promoter genes are cloned successfully , contributing much to screening transcription factors that regulate E-cadherin and N-cadherin expression .

Construction of human Egr-1 promoter and its response to ionizing radiation in tumor cells / 细胞与分子免疫学杂志

AIM: To construct human Egr-1 promoter luciferase reporter system and study its activity induced by i-onizing radiation. METHODS: Egr-1 promoter was obtained by human genomic PCR and cloned into pGL3-basic vector. After transfection of recombinant plasmid into human tumor cells, the Egr-1 promoter activity induced by ionizing radiation was detected by luciferase reporter assay. RESULTS: The luciferasy reporter system of Egr-1 promoter was successfully constructed. The activity of Egr-1 promoter was substantially increased after different doses of IR and reached to the peak at the time point of 48h after IR. CONCLUSION: The Egr-1 promoter was constructed in this study showed IR inducible activity in tumor cells, laying foundation for the research of radiation, mediated gene therapy.