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JiH.Huh,Byung-WanLee,EunS.Kang,BongS.ChaandHyunC.LeeDivisionofEndocrinologyandMetabolism,DepartmentofInternalMedicine,YonseiUniversityCollegeofMedicine,Seoul,KoreaSummaryObjectiveAlthough glycated haemoglobin (A1c) levels are simi-lar among patients with type 2 diabetes, the glycated albumin(GA)/A1c ratio varies considerably. On the basis of the hypo-thesis that endogenous insulin secretion might be correlated withthe GA/A1c ratio, we investigated whether insulin secretory func-tion or insulin resistance has different effects on the GA/A1cratio in patients with type 2 diabetes using the standardizedliquid meal test.Design Aclinical,retrospectivestudy.Patients and measurementsA total of 758 patients with type 2diabetes ingested a standardized liquid meal (i.e. 500 kcal, 17AE5gfat, 68AE5 g carbohydrate and 17AE5 g protein). The subjects weredivided into two groups: those with GA/A1c ratio

This study investigated the adverse health outcomes and urinary heavy metal levels in residents exposed to cement dust, compared to those who were not exposed. A total of 374 residents (276 for the exposed group and 98 for the unexposed group) were surveyed. Participant demographics, health-related behaviors (smoking and drinking), medical history, and clinical symptoms were collected using a self-administered questionnaire. Urinary metal levels were determined using an Atomic Absorption Spectrometer (AAS). Clinical adverse health outcomes such as asthma, rhinitis, and dermatitis were found to be more common in the group exposed to cement dust than in the unexposed group. Urinary levels of chromium and mercury were found to be significantly higher in the exposed group compared to the unexposed group. A limitation of this study is that we did not measure air pollution and heavy metals in local soils and plants and the cement dust could not be concluded as the unique origin of those metals because of other sources of those metals. Although these limitation are, these results suggest that exposure to cement dust may lead to chronic symptoms and disease.

This study was undertaken to investigate diverse risk factors affecting the progression of diabetic nephropathy (DN) by observing the changes of 24 h urinary albumin excretion (24 h UAE) in 90 abdominally obese, normal weight, type 2 diabetic patients with normo- or micro-albuminuria. Patients were divided into three groups according to the 24h UAE; normo-, micro-, and macro-albuminuria group. After 4 years of follow-up, patients were divided into either progression or non-progression group according to the changes of 24 h UAE. About 37% of the normo-albuminuria group and 18% of the micro-albumiuria group were classified into the progression group. The initial serum creatinine levels and the initial and follow-up post-prandial plasma glucose levels were significantly higher in the progression group than in the non-progression group. Most remarkably, the initial and follow-up serum triglyceride (TG) levels (190 +/- 132 versus 132 +/- 49 mg/dl and 191 +/- 124 versus 133 +/- 41 mg/dl, P0.01 in both) were significantly higher in the progression group than in the non-progression group, suggesting hypertriglyceridemia might be included in the progression factors of DN. The increases in 24-hour UAE were positively associated with the initial and follow-up post-prandial plasma glucose levels (P0.05 in both), the initial and follow-up serum creatinine levels (P0.05 in both), and the initial serum TG levels (P0.05). Whereas, insulin users or patients with retinopathy at follow-up (P0.05 in both) showed more rapid progression of albuminuria, ACE inhibitors or acarbose (P0.05 in both) use turned out to protect against it.

To elucidate the correlates of self-rated fatigue in Korean employees.The data for 10,176 (men, 7984; women, 2192; mean age, 34.2; SD: 8.8) employees recruited from a nation-wide sample were examined. A structured questionnaire was used to measure the participants' fatigue, sociodemographics (sex, age, education, and marital status), job-related characteristics (work duration, grade at work, work hours, shiftwork, employment type, and magnitude of workplace), and health-related habits (smoking, drinking, coffee intake, and exercise). Two types of measurement for fatigue were used to evaluate the magnitude of fatigue: self-rated question and a standardized measurement tool (Multidimensional Fatigue Scale: MFS).According to the self-rated fatigue, 32% of employees reported that they felt fatigue for the past two weeks, and 9.6% of males and 8.7% of females had experienced excessive fatigue (6 months or more). Hierarchical multiple regression analysis showed that fatigue measured by MFS was more common in women, younger, college or more graduated, single, and employees who do not regularly exercise. Fatigue was also associated with long work hours, and the size of the workplace (1000 employees).These results suggest that fatigue has been considered as a common complaint, and that it is affected by job-related factors like work hours and the workplace size as well as sociodemographics or health-related behaviors. Further research is needed to clarify the effects of fatigue on adverse health,outcomes, work performance, work disability, sick absence and medical utilization, and to examine the relationship of job characteristics (e.g.: work demand, decision latitude) to fatigue.

To estimate the magnitude of psychosocial distress and examine eligible factors associated with the development of psychosocial distress in Korean employees, using a nationwide sample.A total of 6977 workers were recruited from 245 companies. A structured questionnaire was used to assess sociodemographics, health-related behaviors, job characteristics, social support at work, personality traits (locus of control, type A behavior pattern), self-esteem, and psychosocial distress.The results showed that 23% of workers were categorized as high stress, 73% as moderate, and 5% as normal. Hierarchical multiple regression analysis showed that psychosocial distress was more common in younger workers, both male and female. Regular exercise was negatively associated with increase of psychosocial distress. In job characteristics, as expected, low decision latitude, high job insecurity, and low social support at work were related to high psychosocial distress. Personality traits such as locus of control and type A behavior pattern, and self-esteem were more powerful predictors of psychosocial distress than general characteristics, health-related behavior, and job characteristics. There were some gender differences. While men who are less educated and single (unmarried, divorced, and separated) experienced higher levels of psychosocial distress than those who are educated and married, women who feel high job demand experienced higher levels of psychosocial distress than those who feel low job demand.The proportion of the high stress group was higher than expected, and psychosocial factors like social support and personality characteristics (e.g. locus of control, type A behavior pattern and self-esteem) were more significant factors for psychosocial distress than other variables. This finding suggests that some psychosocial factors, especially inadequate social support, low self-esteem and lack of internal locus of control for the development of psychosocial distress, will also operate as an intervention strategy in the worksite stress reduction program. It is strongly required that worksite stress reduction programs should be established in at both occupational and level as well as in individual levels.

Background . This study examined whether job stress (work demand and decision latitude) is associated with smoking, blood pressure, lipid level (total cholesterol, triglyceride, HDL cholesterol), and homocystein as risk factors for cardiovascular disease in Korean male workers. Methods . Study subjects of this study were recruited from a sample of 1,071 workers in 20 companies of W city and H counties, and they were grouped into four categories (high strain group, active group, passive group, and low strain group) based on the postulation of Karasek's Job Strain Model. Of them, we invited 160 male workers (40 people each subgroup) using a stratified sampling, and finally, 152 eligible participants were analyzed. Results . In multivariate analyses, we found that decision latitude was associated with cholesterol, triglyceride, and homocystein and that work demand was related to smoking and systolic blood pressure. Job strain (the combination of high work demand with low decision latitude) was significantly related to higher levels of homocystein after controlling for age, BMI, smoking, and social support at workplace. Conclusions . These results indicate that job stress is associated with cardiovascular risk factors and might contribute to the development of cardiovascular disease. Some considerations for the future research were discussed.

A growing body of literature has documented that job stress is associated with the development of cardiovascular disease. Nevertheless, the pathophysiological mechanism of this association remains unclear. The purpose of this study is to elucidate the relationship between job stress, heart rate variability, and metabolic syndrome. The study design was cross-sectional, and a total of 169 industrial workers were recruited. A structured-questionnaire was used to assess the general characteristics and job characteristics (work demand, decision latitude). Heart rate variability (HRV) was recorded using SA-2000 (medi-core), and was assessed by time-domain and by frequency-domain analyses. Time domain analysis was performed using SDNN (Standard Deviation of normal to normal interval), and spectral analysis using low-frequency (LF), high-frequency (HF), and total frequency power. Metabolic syndrome was defined on the basis of risk factors being clustered when three or more of the following cardiovascular risk factors were included in the fifth quintile: glucose, systolic blood pressure, high-density lipoprotein cholesterol (bottom quintile), triglyceride, and waist-hip ratio. The results showed that job characteristics were not associated with cardiovascular risk factors. Compared to the lower strain group (low strain+passive+active group), the high strain group had a less favorable cardiovascular risk profile with higher levels of blood pressure, glucose, homocysteine, and clotting factor, but the difference was not statistically significant. The SDNN of HRV was significantly lower in the high strain group than in the low strain group. The prevalence of metabolic syndrome in the lower strain group and high strain group was 13.2% and 23.8%, respectively. In the high strain group, the metabolic syndrome was significantly related to a decreased SDNN. However, we could not find a significant association in LF/HF ratio. This result suggests that decreased HRV found in the high-strain group are not a direct indicator of disease. However, it can induce cardiovascular abnormalities or dysfunctions related to the onset of heart disease among high risk groups.

This study examined the possible relationship between Karasek's job strain model and blood coagulation factors VII and VIII as risk factors for cardiovascular disease in Korean male workers. Based on the postulation of the model, we invited 160 male workers (40 people each subgroup) using a stratified sampling from the base population (n = 1071). In univariate analyses, decision latitude was negatively related to blood coagulation factors VII and VIII. Work demand was positively related to coagulation factor VIII, but not to factor VII. Hierarchical multiple regression analyses showed that job strain was associated with blood coagulation factor VIII after controlling for smoking, blood pressure, total cholesterol, and HDL cholesterol. These results indicate that job characteristics may be related to blood coagulation, and contribute to the development of cardiovascular disease with other classical risk factors.

N,N-dimethylformamide (DMF) is metabolized by the microsomal cytochrome p-450 into mainly N-hydroxymethyl- N-methylformamide (HMMF), which further breaks down to N-methyformamide (NMF). However, the detailed mechanism of its toxicity remains unclear. We investigated the metabolism and the toxicity of DMF using the isolated perfused liver model. DMF was added to the recirculating perfusate of the isolated perfused rat liver at concentrations of 0, 10 and 25 mM. Samples were collected from the inferior vena cava at 0, 30, 45, 60, 75, and 90 minutes following addition of the DMF. The metabolites of DMF were analyzed using Gas-chromatography (GC). The changes in the rate of oxygen consumption by the DMF were monitored during perfusion. The enzyme activities (aspartic aminotransferase:AST, alanine aminotransferase:ALT, and lactic dehydrogenase:LDH)) in the perfusate were monitored to see if DMF caused hepatotoxicity. As the perfusion progressed, the DMF concentration in the perfusate decreased, but the level of NMF increased to a maximum of 1.16 mM. The rate of oxygen consumption increased at DMF concentrations of 10 mM and 25 mM. However, when a known inhibitor of cytochrome p-450, SKF 525A (300 micro M), was used to pretreat the perfusate prior to the addition of the DMF, the rate of oxygen consumption was significantly inhibited, indicating the cytochrome p-450 system was responsible for the conversion of DMF to NMF. On addition of the DMF, the activities of the enzymes AST, ALT and LDH were significantly increased a time and dose dependent manner. However, following pretreatment with SKF 525A, their releases were inhibited.

This research was intended to verify separate and combined effects of cadmium and nickel on blood pressure in rats. After cadmium chloride (CdCl(2)) and nickel chloride (NiCl(2)) were administered individually and combined by intraperitoneal injection to rats daily for a week, systolic blood pressure of the tails were measured at 1, 5, 10, 20, and 30 days after administration. Each substance was injected into rats with 0.1 mg/kg x bw and 1.0 mg/kg x bw concentrations. After 0.1 mg/kg x bw CdCl(2) was injected, statistically significant differences from the control group (only saline) were found at 1, 5, and 10 days. After 0.1 mg/kg x bw NiCl(2) was injected, no statistically significant differences from the control group were found. After 0.1 mg/kg x bw CdCl(2) and 0.1 mg/kg x bw NiCl(2) were injected combined simultaneously, statistically significant differences from the control group were found at 1, 5, and 10 days, compared with the 0.1 mg/kg x bw CdCl(2) group after 5 days and the 0.1 mg/kg x bw NiCl(2) group after 5 and 10 days. After 1.0 mg/kg x bw CdCl(2) was injected, statistically significant differences from the control group were found at 1, 5, 10, and 20 days. After 1.0 mg/kg x bw NiCl(2) was injected, statistically significant differences from the control group were found at 1 and 5 days. After 1.0 mg/kg x bw CdCl(2) and 1.0 mg/kg x bw NiCl(2) were injected combined, statistically significant differences were found at 1, 5, 10, 20, and 30 days, compared with 1.0 mg/kg x bw CdCl(2) at 10, 20, and 30 days and 1.0 mg/kg x bw NiCl(2) at 5, 10, 20, and 30 days. It was found that the effect of CdCl(2) on blood pressure was much more than that of NiCl(2) and the combination of CdCl(2) and NiCl(2) in high concentration delayed recovery of blood pressure.

Objectives: The objective of this study was to determine the relationship of physical and psychosocial risk factors to work-related musculoskeletal upper extremity symptoms amongst automobile manufacturing workers. Methods: The cross-sectional study was conducted using male automobile manufacturing workers in order to examine the relationship of physical and psychosocial risk factors to work-related musculoskeletal upper extremity symptoms. A total of 1,793 male workers were asked to complete a self-administered questionnaire. The questionnaire consisted of questions regarding general characteristics, health related behaviors, work-related characteristics, job stress, ergonomic risk factors, and the presence of musculoskeletal symptoms (neck, shoulder, arm, and hand). Work-related musculoskeletal symptoms were evaluated using the National Institute of Occupational Safety and Health (NIOSH) surveillance criteria. In order to measure the physical risk factors, the American National Standard Institute (ANSI) Z-365 Quick checklist was incorporated into the questionnaire. Job stressors were measured using the Korean Occupational Stress Scale (KOSS). A binary logistic regression analysis was performed that examined the relationship of physical and psychosocial risk factors to musculoskeletal symptoms. Results: The result showed that the physical and psychosocial risk factors were associated with musculoskeletal upper extremity symptoms. The workers with high physical risk factors reported more musculoskeletal symptoms than those having low physical risk factors (OR: 2.37, 95% CI: 1.56~3.62). The workers with high job stress were more likely to have an increased risk of musculoskeletal upper extremity symptom compared to those with normal job stress (OR: 2.65, 95% CI: 2.03~3.47). A significant relationship between the combined effects of physical and psychosocial risk factors on musculoskeletal upper extremity symptoms was also found. The workers exposed to high physical risk factors, high job stress, and long working hours were more likely to report musculoskeletal symptoms than those having low physical risk factors, normal job stress and moderate working hours(OR: 2.37, 95% CI: 1.56~3.62). Conclusions: The results suggest that some physical and psychosocial risk factors increase the risk of work-related musculoskeletal upper extremity symptoms amongst automobile manufacturing workers. In order to prevent or reduce musculoskeletal disorders amongst automobile manufacturing workers, it is strongly recommended to manage the physical psychosocial risks occurring in the workplace.

Department of Preventive Medicine and Institute of Occupational Medicine, Wonju College of Medicine, Yonsei University Department of Preventive and Occupational Medicine, College of Medicine, Pusan University Department of Occupational and Environmental Medicine, Pocheon CHA University Korean Women’s Development Institute Department of Occupational Medicine, College of Medicine, Chosun University Department of Preventive Medicine, College of Medicine, Chosun University Department of Family Medicine, Hallym University College of Medicine

Korean Medical Licensing Examination(KMLE) 2002 focused on evaluation of the integrative medical knowledge such as primary clinical care or problem-solving competence. We analyzed the correlation among the year-wise student academic scores(grade score), trial examination scores and KMLE score by correlation analysis and multiple regression method. Four times of trial examination were taken in 2001, which were composed according to the principles of KMLE. Trial examination scores were significantly correlated with student grade scores (p

3 ) Objective: A growing body of literature has documented that job stress is associated with the development of cardiovascular disease. Nevertheless, the pathophysiological mechanism of this association remains unclear. Therefore, we tried to elucidate the relationship between job stress, heart rate variability and metabolic syndrome. Method: The study design was cross-sectional, and 169 industrial workers were recruited. A structured-questionnaire was used to assess the general characteristics and job characteristics (work demand, decision latitude). Heart rate variability (HRV) was recorded using SA-2000 (medi-core). HRV was assessed by time-domain and by frequency-domain analyses. Time domain analysis was performed for SDNN (Standard Deviation of NN interval), and spectral analysis for low-frequency (LF), high-frequency (HF) and total frequency power. Metabolic syndrome was defined on the basis of clustering of risk factors, when three or more of the fol - lowing cardiovascular risk factors were included in the fifth quintile: glucose, systolic blood pressure, HDL-cholesterol (bottom quintile), triglyceride and waist-hip ratio. Results: The results showed that job characteristics were not associated with cardiovascular risk factors. The high strain group had a less favorable cardiovascular risk profile with higher levels of blood pressure, glucose, homocysteine, and clotting factor than the lower strain group (low strain+passive+active group), but the difference was not statistically significant. The SDNN of HRV was significantly lower in the high strain group than in the low strain group. The prevalence of metabolic syndrome in the low strain, passive, active and high strain groups was 9.7%, 13.9%, 14.9% and 23.8%, respectively. In the high strain group, the metabolic syn - drome was significantly related to a decreased SDNN. However, we could not find a significant association in LF/HF ratio. Conclusion: This result suggests that decreased HRV does not play a role in the development of disease; however, it can induce cardiovascular abnormalities or dysfunctions related to the onset of heart disease among high risk groups.