[An assembly line lighting survey analysis and its optimal illumination range research].

OBJECTIVE: To investigate and analyze present conditions of the assembling line illumination in our country, and to set the recommended values of illuminance standard. METHODS: Questionnaires and field surveys were used in this investigation. A total of 752 workers from seven factories in textile, shoes and electronics industries were selected for the questionnaire survey and site measurement, and corresponding analyses made with SPSS 13.0 statistic software. RESULTS: Uniformity of illumination, definition in working face, general satisfactory degrees, asthenopia were significantly correlated with each other. Assembly line illuminances for five different visual characteristics were recommended in this paper. The illuminances were 500-1 000-1 500 lx, 300-500-1 000 lx, 200-300-750 lx, 100-300-500 lx, 50-100-200 lx, respectively. CONCLUSION: Present conditions of the assembling line illumination are less than satisfactory, uniformity of illumination is on the low side, and there is no assembling line illuminance standard for general satisfactory degrees and asthenopia of workers. The related work should be further improved.

[The analysis of factors influencing the work related musculoskeletal disorders of oil drillers].

OBJECTIVE: To investigate the morbidity and influence factors of work-related musculoskeletal disorders (WMSD) in oil drillers. METHODS: The modified Nordic Standardized Questionnaire for WMSD was used to perform the epidemiological investigation in 860 oil drillers. RESULTS: The predominant sites of WMSD in the oil drillers were waist (50.6%), neck (29.8%) and shoulder (23.4%), respectively. There were significant differences of the WMSD morbidities in all body sites except for wrist and hip among groups with different working years (P < 0.05 of P < 0.01). The WMSD morbidities in the neck, shoulder, back and waist of oil drillers working for more than 40h a week were significantly higher than those of oil drillers working for less than 40 ha week (P < 0.05). The results of logistic regression analysis revealed that some occupational factors, i.e. keeping stoop and stand for long time, repeating trunk bend, keeping awkward lift posture and lifting the heave objects, were the risk factors for WMSD at waist (P < 0.05), also some management factors, i.e. overtime work and inadequate rest, were the risk factors for WMSD at waist (P < 0.05). CONCLUSION: The WMSD appears to be a serious ergonomic problem in oil drillers, it is necessary to correct working posture, reduce working load, improve organizational management, and encourage a workplace health program with regular work and rest.

[The interactive effect of job task and psychosocial factors on work-related musculoskeletal disorders].

OBJECTIVE: To investigate the interactive effect of job task and psychosocial factors on the outcomes of musculoskeletal disorders. METHODS: 653 workers from different type of manufacturing industries and administration office recruited in a cross-sectional epidemiological survey. The Quick Exposure Check (QEC) was applied to assess the ergonomic load of job task, Job Content Questionnaire (JCQ) for identifying psychological characteristics, and Nordic Standardized Questionnaire for investigating outcomes of WMSDs. RESULTS: The prevalence of WMSD in shoulder, upper back, lower back and hand/wrist were significantly different under a variety of combined job task and psychosocial characteristics (P < 0.05 or P < 0.01). The more physical and psychological loads, the higher prevalence of WMSDs were revealed. By using multivariate analyses, a potential interactive effect was found in terms of the WMSDs symptoms in hand/wrist, shoulder, upper back and lower back after adjusted by work year, age, and gender. CONCLUSIONS: Higher physical load and greater psychosocial risk are more frequent self-reported symptoms of WMSDs than those of lower exposures. Ergonomic intervention strategies aimed at reducing the incidence of WMSDs should not only be focused on control of physical work factors but also psychosocial risks of relevance.

Expression and enzyme activity determination of human cyclooxygenase-1 and -2 in a baculovirus-insect cell system.

AIM: To develop an in vitro intact cell-based assay for screening selective cyclooxygenase inhibitors. METHODS: Human cyclooxygenase-1 (hCOX-1) and cyclooxygenase-2 (hCOX-2) genes were cloned from human monocyte cell line THP-1 cells and expressed in Spodoptera frugiperda (sf9) insect cell line by Bac-to-Bac baculovirus expression systems. Infected sf9 cells were harvested 24 h post-infection (hpi), and distributed to a 24-well plate, preincubated with various nonsteroidal anti-inflammatory drugs, and challenged with 10 mmol/L arachidonic acid; the cyclooxygenase activity was assessed indirectly by prostaglandin E2-specific radioimmunoassay. RESULTS: Polymerase chain reaction detection demonstrated that hCOX-1 and hCOX-2 were transposed to the bacmid. Western blot analysis showed that infected sf9 cells could express hCOX-1 and hCOX-2 proteins. Radioimmunoassay demonstrated that both recombinant proteins functioned well in sf9 cells. CONCLUSION: Human cyclooxygenase-1 and cyclooxygenase-2 were successfully expressed in sf9 insect cell line. It can be utilized for the identification of potent and selective inhibitors of hCOX-1 and/or hCOX-2.