OBJECTIVES: Reduced heart rate variability (HRV) is one of the serious risk factors for heart diseases. We evaluated the acute and chronic effects of work-related factors on HRV. METHODS: The five-minute HRV of 85 male workers from an automobile assembly factory were measured at 9 A.M. (before-work) and at 5 P.M. (after-work). The workplace noise, temperature and physical workload levels were measured as work-related factors. We postulated that the HRV measured at beforework represents the chronic effects and the HRV measured at after-work represents the acute effects of work-related factors. We used generalized linear regression analysis with adjusting for the general characteristics and/or the morning HRV. RESULTS: The subjects exposed to noise or a hot environment showed increased HRV in the afternoon and decreased HRV in the morning. Machine oil and interpersonal conflict decreased the HRV in the morning, but other chemicals did not show any effect on the HRV. A physical workload decreased the HRV in both the morning and afternoon. CONCLUSION: The physical and chemical environment, psychosocial stress and a physical workload may affect the autonomic nerve system.
Automobiles ; Autonomic Pathways ; Heart ; Heart Diseases ; Heart Rate ; Humans ; Linear Models ; Male ; Noise ; Risk Factors

OBJECTIVE: This study was performed to investigate the association between work ability and job stress factors in three manufacturing industries. METHODS: The data were gathered from 705 workers of 3 manufacturing industries, from August 2007 to January 2008. A structured, self-reported questionnaire was used to access the demographic, socioeconomic and work related characteristics. Work ability and job stress factors were determined using two questionnaires: the work ability index (WAI) of the Finnish Institute of Occupational Health and the Korean Occupational Stress Scale (KOSS), respectively. RESULTS: According to the logistic regression analysis results, WAI was related to job stress factors after adjustment for age, shift work, employment type and exercise. Of the eight subscales, job demand, interpersonal conflict, lack of reward, occupational climate and total score were significantly associated with WAI. In the analysis of each factory, interpersonal conflict, job insecurity and lack of reward were significantly associated with WAI in factory II, and organizational system, lack of reward and total score in factory III, but there was no significant association in factory I. CONCLUSIONS: Job stress factors were significantly associated with WAI in two of the three manufacturing industries. Further and more detailed study needs to be conducted to reduce the job stress and improve the work ability.
Climate ; Employment ; Logistic Models ; Occupational Health ; Questionnaires ; Reward

Bone diseases such as osteoporosis and periodontitis are induced by excessive osteoclastic activity, which is closely associated with inflammation. Benzydamine (BA) has been used as a cytokine-suppressive or non-steroidal anti-inflammatory drug that inhibits the production of pro-inflammatory cytokines or prostaglandins. However, its role in osteoclast differentiation and function remains unknown. Here, we explored the role of BA in regulating osteoclast differentiation and elucidated the underlying mechanism. BA inhibited osteoclast differentiation and strongly suppressed interleukin-1 (IL-1) production. BA inhibited osteoclast formation and bone resorption when added to bone marrow-derived macrophages and differentiated osteoclasts, and the inhibitory effect was reversed by IL-1 treatment. The reporter assay and the inhibitor study of IL-1 transcription suggested that BA inhibited nuclear factor-B and activator protein-1 by regulating IB kinase, extracellular signal regulated kinase and P38, resulting in the down-regulation of IL-1 expression. BA also promoted osteoblast differentiation. Furthermore, BA protected lipopolysaccharide- and ovariectomy-induced bone loss in mice, suggesting therapeutic potential against inflammation-induced bone diseases and postmenopausal osteoporosis.