BACKGROUND: Double gene transfection using bone morphogenetic protein 2 (BMP2) and vascular endothelial growth factor 165 (VEGF165) for bone marrow stromal stem cells (BMSCs) to induce osteogenesis provides experimental basis for the study on tissue engineering bone. OBJECTIVE: To investigate the ability of BMP2 and VEGF165 double gene modified rat BMSCs to induce osteogenesis. METHODS: BMSCs were isolated from the femur and tibia of four 4-week-old Sprague-Dawley rats by whole bone marrow adherent culture. Passage 3 BMSCs were randomized into five groups: non-transfection group, empty plasmid group, BMP2 transfection group, VEGF165 transfection group, BMP2 and BMP2/VEGF165 transfection group (co-transfection group). Then, western blot assay was used to detect expression of BMP2 and VEGF165 at 48 hours after transfection, and the activity of alkaline phosphatase was detected in each group at 7 days after transfection. RESULTS AND CONCLUSION: Highly expressed BMP2 in BMP2 and co-transfection groups and highly expressed VEGF165 in VEGF165 and co-transfection groups were found after transfection. The expression of BMP2 or VEGF165 in the co-transfection group was significantly higher than that in the BMP2 or VEGF165 transfection group after transfection, respectively (P < 0.05). Western blot results showed that the activity of alkaline phosphatase was ranked as: co-transfection group > BMP2 transfection group > VEGF165 transfection group > empty plasmid group and non-transfection group. There was a significant difference in the activity of alkaline phosphatase between co-transfection group and any of single gene transfection groups (P < 0.05). To conclude, BMP2/VEGF165 co-transfection promotes the ectopic osteogenesis of BMSCs.

OBJECTIVETo investigate the effect of occupational exposure to toluene diisocyanate (TDI) on the workers' health.

METHODSA total of 76 workers exposed to TDI (exposure group) and 64 management staff members (control group) were selected from a factory as the study subjects. Area sampling was performed for the place with exposure to TDI according to the method in GBZ 159-2004 Specifications of air sampling for hazardous substances monitoring in the workplace, and gas chromatography was applied to measure the concentration of TDI in workplace air. The workers' personal information was collected with questionnaire, pulmonary ventilation function was determined with a portable spirometer, hematological parameters were analyzed by automatic blood analyzer and blood chemistry analyzer, and the indicators of oxidative damage and energy metabolism were measured by the reagent kit provided by Nanjing Jiancheng Bioengineering Institute. SPSS 17 software was applied for statistical analysis.

RESULTSThe exposure group had significantly lower forced vital capacity (FVC), forced expiratory volume in 1 second(FEV1.0), and FEV1.0/FVC ratio than the control group (P <0.05). Compared with the control group, the exposure group had significantly higher red blood cell count, platelet distribution width, mean platelet volume, lymphocyte count, and neutrophil count(P<0.01), and significantly lower activities of lactate dehydrogenase(LDH), superoxide dismutase, and succinodehydrogenase (SDH)(P <0.01). In the exposure group, the length of exposure was negatively correlated with the activities of SDH and LDH in the serum (r=-0.319, P <0.05; r=-0.239, P <0.05), and the length of exposure was not found to be correlated with the activity of SOD and pulmonary function indices.

CONCLUSIONTDI can induce inflammatory response and lung ventilation function impairment in workers exposed to TDI, as well as oxidative stress and imbalance of energy metabolism. Therefore, it can cause damage to workers' health, and protective measures should be enhanced.

Case-Control Studies ; Erythrocyte Count ; Forced Expiratory Volume ; Humans ; Inflammation ; physiopathology ; L-Lactate Dehydrogenase ; blood ; metabolism ; Leukocyte Count ; Lung ; physiopathology ; Occupational Exposure ; adverse effects ; Pulmonary Ventilation ; Succinate Dehydrogenase ; blood ; metabolism ; Superoxide Dismutase ; metabolism ; Toluene 2,4-Diisocyanate ; adverse effects ; Vital Capacity

Objective: To investigate the current status of the occupational hazards of welding fume, manganese, and manganese compounds in the welding environment of a large container manufacturing enterprise, as well as the status of occupational health examination of workers, and to provide a basis for improving the welding environment of this enterprise. Methods: In August 2016, July 2017, and August 2018, convenience sampling was used to perform an on-site occupational hygiene survey of the welding workshop for three consecutive years, and welding fume, manganese and, manganese compounds (counted as manganese dioxide) were measured for their workplace exposure concentrations and exposure levels in workers. A comprehensive analysis was performed for the results of occupational health examination. Results: Welding fume, manganese, and manganese compounds in the welding environment gradually increased from 2016 to 2018 (χ²_trend=5.14 and 5.54, P<0.05). The maximum over-standard rate of concentration-short term exposure limit was 43.3% (13/30) for welding fume and 40.0% (12/30) for manganese and its compounds, and the maximum over-standard rate of time-weighted average concentration was 26.7% (8/30) for welding fume and 23.3% (7/30) for manganese and its compounds. Abnormalities were observed in the occupational health examination of welding workers in 2016-2018, among which respiratory system abnormalities (cough, expectoration, and wheezing), nervous system abnormalities (dizziness, fatigue, sleep disorders, amnesia, hyperhidrosis, and palpitations), and electrocardiogram abnormalities (bundle conduction block) had an incidence rate of above 10.0%, and the incidence rate of abnormalities on posterior-anterior X-ray high-kV chest radiograph was close to 8.9% (30/336) . Conclusion There is severe exposure to welding fume, manganese, and manganese compounds among workers in this enterprise, which cause great hazards to the health of workers. It is necessary to strengthen occupational health management, take measures to improve the welding environment, and enhance occupational disease prevention.