The Risk Factors of Metabolic Syndrome and its Relation with gamma-GTP in Steel-mill Workers / 대한산업의학회지

OBJECTIVES: This study was performed to estimate the prevalence and possible risk factors of the metabolic syndrome in steel-mill workers, and to evaluate the relation between gamma-glutamyltransferase (gamma-GTP) and the metabolic syndrome. METHODS: The study subjects comprised 1,604 male steel-mill workers. The indices of metabolic syndrome, such as BMI, triglyceride, HDL-cholesterol, blood pressure, fasting glucose, and gamma-GTP were analyzed in each subject. We collected information about demographic characteristics, behavioral patterns, such as alcohol drinking, smoking, and exercise, and family medical history through a self-administered questionnaire. Statistical analysis was done by using the chi-square test, Mantel-Haenszel trend test and logistic regression model. RESULTS: The crude and age-adjusted prevalences of the metabolic syndrome were 21.3% and 15.5%, respectively, in the steel-mill workers. Age (OR: 1.063, 95% CI: 1.033-1.094), alcohol drinking (OR: 1.657, 95% CI: 1.175-2.337) and smoking (OR: 1.359, 95% CI: 1.017-1.816) were risk factors for the metabolic syndrome. Meanwhile, shift work showed a significant relation with hypertension (OR: 1.329, 95% CI: 1.038-1.700), but not with other metabolic syndrome components. However, tenure, exercise and family medical history were not significant factors for the metabolic syndrome in this study. The risk ratio of the metabolic syndrome (OR: 3.345, 95 % CI: 2.534-4.416) and its components, such as obesity, hypertriglyceridemia, hypertension and hyperglycemia, were higher in the high gamma-GTP group (> or =63 IU/ liter) than in the controls (<63 IU/liter). CONCLUSIONS: These results confirm the need for health education to control the metabolic syndrome by improving behavioral patterns, such as alcohol drinking and smoking, in factory workers. In addition, it is suggested that gamma-GTP might be a useful candidate in screening for the metabolic syndrome.

Role of NO in Activation of NFkB by PM 2.5 in Lung Epithelial Cells / 결핵

BACKGROUND:The present study was performed to further improve our understanding of the molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the inflammatory response in the lung, by particulate matter in lung epithelial cells wit an aerodynamic diameter of less than 2.5 micro meter(PM2.5). METHODS: Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), IkB degradatio and NFkB-dependent transcrptional activity, in A 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM 2.5-induced NFkB activation in A 549 cells. RESULTS:The rapid degradation of IkB and the increase of transcriptional activity of the NFkB-dependent promotor were observed in A 549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A 549 cells was not clearly detected, although immediate responses were observed in RAW 264.7 cells. A549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced IkB degradation and the increase of the NFkB-dependent transcriptional activity. CONCLUSION: These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of NFkB in the pulmonary epithelium.

Role of NO in Activation of NFkB by PM 2.5 in Lung Epithelial Cells / 결핵

BACKGROUND:The present study was performed to further improve our understanding of the molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the inflammatory response in the lung, by particulate matter in lung epithelial cells wit an aerodynamic diameter of less than 2.5 micro meter(PM2.5). METHODS: Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), IkB degradatio and NFkB-dependent transcrptional activity, in A 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM 2.5-induced NFkB activation in A 549 cells. RESULTS:The rapid degradation of IkB and the increase of transcriptional activity of the NFkB-dependent promotor were observed in A 549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A 549 cells was not clearly detected, although immediate responses were observed in RAW 264.7 cells. A549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced IkB degradation and the increase of the NFkB-dependent transcriptional activity. CONCLUSION: These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of NFkB in the pulmonary epithelium.

The Role of TNFalpha Gene Promoter Polymorphism in the Development of Coal Workers' Pneumoconiosis / 대한산업의학회지

OBJECTIVES: This study was performed in order to investigate the frequency of the TNF2 allele in patients with coal workers pneumoconiosis (CWP). METHODS: We compared the genotype distribution of TNFalpha gene promoter polymorphism between 80 CWP patients and 54 healthy controls. RESULTS: The results were as follows : 1. The rare allele TNF2 was significantly more frequent in CWP patients (20.6 %) than in controls (10.2 %). 2. The spontaneous or LPS-induced release of TNFalpha from the peripheral monocytes was slightly increased in the TNF2 group, but these values were not significantly different between groups. 3. In the CWP TNF2 group, the increase of LPS-induced TNFalpha release was significant in comparison with that of the controls. CONCLUSIONS: From the above results, we suggest that the TNF2 allele is strongly associated with susceptibility to CWP development.

Autoregulation of Quartz-induced iNOS by iNOS-derived Hydrogen Peroxide in Rat2 Fibroblast / 대한산업의학회지

OBJECTIVES: This study was performed in order to investigate the molecular mechanism regulating nitric oxide synthase(NOS) induced by alpha-quartz in Rat2 fibroblast. METHODS: alpha-quartz-induced nitric oxide(NO) and H2O2 formation and alpha- quartz-induced iNOS protein expression in Rat2 fibroblast were monitored. With iNOS inhibitor(L-N6- (1-iminoethyl)lysine hydrochloride, L-NIL) or antioxidant(catalase), we observed NO and H2O2 formation and iNOS protein expression in Rat2 fibroblast stimulated with alpha-quartz. RESULTS: alpha-quartz stimulated iNOS-induced NO and H2O2 formation in Rat2 fibroblast. L-NIL inhibited H2O2 formation and iNOS protein expression by alpha-quartz in Rat2 fibroblast. Pretreatment with catalase blocked the autoinhibitory pathway of iNOS by iNOSinduced H2O2, therefore H2O2 and NO production and iNOS protein expression were increased in Rat2 fibrobalst stimulated with alpha-quartz CONCLUSIONS: alpha-quartz-induced iNOS stimulated H2O2 formation in Rat2 fibroblast. INOS-induced H2O2 by alpha-quartz plays an important role in the autoinhibition pathway for regulating the iNOS function in Rat2 fibroblast

Autoproliferation of Fibroblast by Exposure to Crystalline Silica - Evaluation by H2O2 and PDGF-AA and TGF beta / 대한산업의학회지

OBJECTIVES: The aim of this study is to find out the activity of autoproliferation of ratfibroblast exposed to crystalline silica and the role of mediators secreted from rat fibroblast. METHODS: The effect of alpha-quartz on production of growth factor (platelet-derived growth factor-AA and transforming growth factor beta)from rat fibroblasts were evaluated by ELISA and immunocytochemical analysis. Gene expression of these growth factors in rat fibrobast exposed to crystalline silica was evaluated by RT-PCR. Furthermore, fibroblast proliferation by culture supernatant of rat fibroblast was assayed by the neutral red test. RESULTS: The amounts of H2O2 and growth factors synthesized in rat fibroblasts were significantly increased by the stimulation of crystalline silica(alpha-quartz), which showed the dose-dependent manner to the concentration of alpha-quartz with the maximum response at the dosage of 100 microgram/cm2. The result of RT-PCR demonstrated that alpha-quartz induced gene expression of PDGF-AA and TGFbeta in rat fibroblast. We also found that supernatant of alpha-quartz-cocultured rat fibroblast induced a significant proliferation of fibroblast. CONCLUSION: Crystalline silica directly induce functional change in fibroblast such as increased release of reactive oxygen species and growth factors. The products of these functional change promote fibroblast proliferation via autocrine loop.

Department of Questionnaire Measuring Quality of Life in Pneumoconioses / 결핵

BACKGROUND: Pneumoconiosis, like other chronic respiratory diseases, is essentially incurable and, for many, pregressive. While improved survival time is an important aim of treatment, there is growing recognition that for some people, improving the quality of life is more important than extending the length of life. Recently the measurement of the quality of life is used to assess the efficacy of therapeutic agents. METHODS: We interviewed 63 pnemoconiotics who were admitted to St. Mary's Hospital between April and August 1999, using COOP charts, Chronic Respiratory Questionnaire (CRQ), and a newly developed questionnaire concerning clinical and socioeconomic features of the pneumoconiotics - Pneumoconiotic Respiratory Questionnaire (PRQ). Also, ILO classification of the chest film, pulmonary function test, and arterial blood gas analysis of the patients were evaluated. Then we compared the scores between insurace assisted and non-insurance assisted patients, and between clinically stable and unstable patients. RESULRS: Domains of CRQ and PRQ showed a high internal consistency reliability (alpha =0.86-0.89, 0.77-0.81) except the dyspnea domain(alpha=0.63) of CRQ. The scores of CRQ and PRQ showed statistically significant correlations with the results of COOP charts, pulmonary function test and arterial blood gas analysis. The dyspnea domain and socia l activity domain of the PRQ showed significant difference between insurance assisted and non-insurance assisted patients, and between clinically stable and unstable patients. CONCLUSION: Korean translation of the Chronic Respiratory Questionnaire and the newly developed Pneumoconiotic Respiratory Questionnaire are reliable and valid method and are likely to be useful for the measuring of quality of life in patients with the chronic respiratory disease including pneumoconiosis.