OBJECTIVES: The prevalence of aged individuals in the Korean workforce continues to increase. This research determined the health and working conditions of Korean older wage workers and confirmed the effects of factors on the health-related quality of life of Korean older workers. METHODS: Of the 25,534 persons surveyed in the fifth Korea National Health and Nutrition Examination Survey, 1368 older (>55 years of age) wage workers without missing variables were selected. Their general characteristics, health status (cardiovascular disease, musculoskeletal disease, and mental health), working conditions (type of occupation, employment status, full- or part-time work, weekly average working hours, and shift work), and health-related quality of life assessed by the EQ-5D questionnaire were examined. RESULTS: The mean values of the EQ-5D index of the male and female older workers were 0.956 +/- 0.087 and 0.917 +/- 0.124, respectively (p < 0.001). The factors that caused statistically significant differences in the EQ-5D index for all subjects were age, education, household income, cerebro-cardiovascular event, osteoarthritis, musculoskeletal pain, stress, occupation type, employment status, and working hours. In logistic regression analysis, the factors that associated with perceived problems in each EQ-5D dimensions were age, musculoskeletal pain, stress, diabetes, smoking, occupation type, employment status, and working hours. CONCLUSIONS: To eventually raise the quality of life of older workers through health maintenance and management, it is necessary to manage related factors that include of musculoskeletal pain and diseases, stress, diabetes, smoking, occupation, employment status, and working hours.
Education ; Employment ; Family Characteristics ; Female ; Humans ; Korea ; Logistic Models ; Male ; Musculoskeletal Diseases ; Musculoskeletal Pain ; Nutrition Surveys ; Occupations ; Osteoarthritis ; Prevalence ; Quality of Life* ; Salaries and Fringe Benefits ; Smoke ; Smoking

PURPOSE: This study was performed to obtain baseline information about the occupational and environmental medicine(OEM) residency programs in Korea. METHODS: We surveyed 39 residents for the present training condition, satisfaction, vision of OEM, the condition and satisfaction after residency programs by self- administered questionnaire. RESULTS: Residents want to get appropriate clinical and practical training to be a medical director in a factory or specialist of the occupational medicine based at a hospital. They report, however, that current system for OEM residency training program is not appropriate. The curricula, duration of the each curriculum, level of training hospital or institute need to be reconsidered. CONCLUSIONS: We need to develop more systematic residency program with support from government and OEM society.
Curriculum ; Education ; Environmental Medicine* ; Humans ; Internship and Residency* ; Korea* ; Occupational Medicine ; Physician Executives ; Specialization ; Surveys and Questionnaires

BACKGROUND: With increasing use of medical radiologic procedures, wearing proper protector should be emphasized to reduce occupational radiation exposures. This research describes the rates of lead apron wearing for radiation protection and assessed occupational factors related to wearing rates for various types of healthcare professionals. METHODS: We conducted a self-administered questionnaire survey through a website, on-site visits, fax, and mail. Of the 13,489 participants, 8858 workers who could not completely separate themselves from radiological procedure areas. Their general characteristics (sex and age), work history (job title, duration of employment, and hospital type), and practices (frequency of radiation procedures, ability to completely separate from radiation, and frequency of wearing protective lead aprons) were examined. RESULTS: The mean rate of lead apron wearing during radiologic procedures was 48.0 %. The rate was different according to sex (male: 52.9 %, female: 39.6 %), hospital type (general hospital: 63.0 %, hospital: 51.3 %, clinic: 35.6 %, dental hospital/clinic: 13.3 %, public health center: 22.8 %), and job title (radiologic technologist: 50.3 %, doctor: 70.3 %, dentist/dental hygienist: 15.0 %, nurse/nursing assistant: 64.5 %) (p < 0.001). By logistic regression analysis stratified by job title, use of lead aprons by radiologic technologists and nurses/nursing assistants was associated with hospital type and exposure frequency score. For doctors, apron wearing was associated with employment duration. For dentists/dental hygienists, apron wearing was associated with the exposure frequency score. CONCLUSIONS: To improve working environments for healthcare professionals exposed to radiation, it is necessary to consider related factors, such as job title, duration of employment, and hospital type, when utilizing a planning and management system to prevent radiation-related health problems.
Delivery of Health Care* ; Employment ; Female ; Humans ; Logistic Models ; Postal Service ; Public Health ; Radiation Protection

It was recently reported that the C(max) and AUC of rosuvastatin increases when it is coadministered with telmisartan and cyclosporine. Rosuvastatin is known to be a substrate of OATP1B1, OATP1B3, NTCP, and BCRP transporters. The aim of this study was to explore the mechanism of the interactions between rosuvastatin and two perpetrators, telmisartan and cyclosporine. Published (cyclosporine) or newly developed (telmisartan) PBPK models were used to this end. The rosuvastatin model in Simcyp (version 15)'s drug library was modified to reflect racial differences in rosuvastatin exposure. In the telmisartan–rosuvastatin case, simulated rosuvastatin C(maxI)/C(max) and AUC(I)/AUC (with/without telmisartan) ratios were 1.92 and 1.14, respectively, and the T(max) changed from 3.35 h to 1.40 h with coadministration of telmisartan, which were consistent with the aforementioned report (C(maxI)/C(max): 2.01, AUCI/AUC:1.18, T(max): 5 h → 0.75 h). In the next case of cyclosporine–rosuvastatin, the simulated rosuvastatin C(maxI)/C(max) and AUC(I)/AUC (with/without cyclosporine) ratios were 3.29 and 1.30, respectively. The decrease in the CL(int,BCRP,intestine) of rosuvastatin by telmisartan and cyclosporine in the PBPK model was pivotal to reproducing this finding in Simcyp. Our PBPK model demonstrated that the major causes of increase in rosuvastatin exposure are mediated by intestinal BCRP (rosuvastatin–telmisartan interaction) or by both of BCRP and OATP1B1/3 (rosuvastatin–cyclosporine interaction).
Area Under Curve ; Cyclosporine ; Drug Interactions* ; Rosuvastatin Calcium*

As prediction of rapidly aging society, bone health is considered increasingly important and received more attention than ever. Bone health is regulated by balancing between bone resorptive osteoclasts and bone formative osteoblasts. Disruption of balance between bone-resorbing osteoclasts and bone-forming osteoblasts results in bone disease. Natural products have recently received much attention as an alternative tool for the development of novel therapeutic strategy. Baicalein is reported it has anti-cancer, anti-inflammatory and antioxidant effects. Baicalein also has been known that it has both promotive effect on MC3T3-E1 cell line and inhibitory effect on RAW 264.7 cell line. However, the inhibitory mechanism of baicalein using bone marrow derived macrophages (BMMs) on osteoclast differentiation remains not clear. In this study, the suppressive mechanism by baicalein on osteoblast differentiation was evaluated. Bicalein inhibited receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in BMMs in a dose dependent manner without any toxicity. Baicalein suppressed phosphorylation of protein kinaseB (Akt), c-Jun N-terminal kinases (JNK) and phosphoinositide-specific phospholipaseCgamma2 (PLCgamma2). Furthermore, Baicalein suppressed the induction of RANKL-induced c-Fos and Nuclear factor of activated T cell c1 (NFATc1), essential genes on osteoclastogenesis. In BMMs, Bicalein inhibited the mRNA expression of tartrate-resistant acid phosphatase (TRAP), osteoclast-associated receptor (OSCAR), cathepsinK, dendritic cell-specific transmembrane protein (DC-STAMP). Moreover, baicalein promoted differentiation of osteoblast on bone marrow stromal cells (BMSCs). Taken together, these results suggest that baicalein has a potential for treating bone lytic diseases, such as osteoporosis, periodontitis, and rheumatoid arthritis.
Acid Phosphatase ; Aging ; Antioxidants ; Arthritis, Rheumatoid ; Biological Products ; Bone Diseases ; Bone Marrow* ; Cell Line ; Genes, Essential ; Macrophages* ; Mesenchymal Stromal Cells ; Osteoblasts ; Osteoclasts* ; Osteoporosis ; Periodontitis ; Phospholipase C gamma ; Phosphorylation ; Phosphotransferases ; RANK Ligand ; RNA, Messenger

OBJECTIVES: Vitamin D deficiency is increasing worldwide. However, few studies have attempted to examine the vitamin D status of wage workers and the correlation between vitamin D deficiency and working conditions. Hence, we aimed to evaluate the prevalence of vitamin D deficiency and the association between occupational conditions and vitamin D deficiency among Korean wage workers. METHODS: Wage workers aged 20-65 years from the 5th Korea National Health and Nutrition Examination Survey (KNHANES 2010-2012; n = 5409) were included in our analysis. We measured the prevalence of vitamin D deficiency and identified the correlations with the working conditions of these subjects. RESULTS: The prevalence of vitamin D deficiency in male and female subjects was 69.5% and 83.1%, respectively. Among the male subjects, a significant correlation between vitamin D deficiency and working conditions was observed among shift workers, office workers, and permanent workers. No significant correlation with any type of working conditions was observed among female subjects. CONCLUSION: The prevalence of vitamin D deficiency among Korean wage workers was very high and was found to correlate significantly with working conditions, likely because of insufficient exposure to sunlight associated with certain types of work. Wage workers require more frequent outdoor activity and nutrition management to maintain sufficient vitamin D level.
Female ; Humans ; Korea* ; Male ; Nutrition Surveys* ; Prevalence ; Salaries and Fringe Benefits* ; Sunlight ; Vitamin D Deficiency ; Vitamin D* ; Vitamins*

SKL10406, triple monoamine reuptake inhibitor, is a novel antidepressant candidate. A PET study was performed to investigate the occupancies of serotonin and dopamine transporters (SERT and DAT) in human brain, and the relationship between SKL10406 concentration and SERT occupancy was assessed using pharmacokinetic-pharmacodynamic (PK-PD) modeling methods. Fifteen healthy volunteers were given SKL10406 100 mg/day for 6 days or 150 mg/day for 6 days after 100 mg/day for 4 days. Each subject underwent full PK sampling for SKL10406 and PET scans at predose, 4 h and 16 h after dosing at a steady state to investigate the occupancies of SERT and DAT using 11C-DASB and 11C-PE2I, respectively. Naive pooled method (NPM) and nonlinear mixed-effect methods (ME) including a direct ME (DME) and an effect compartmental ME (EME) were used (NONMEM Ver. 7.2). Six and five subjects completed the studies for SERT and DAT, respectively. The final estimates of Emax (53.4%) and EC50 (11.8 ng/mL) from DME were relatively lower than those from NPM (Emax, 74.1%; EC50, 36.8 ng/mL) and EME (Emax, 68.6%; EC50, 40.2 ng/mL). DAT occupancy results were not modeled because of lower occupancies. The results showed that the dosage regimens may be applied in patient studies. However, difference between estimation methods alerts that ME may not be a recommendable analysis tool for sparsely sampled PET scan data.
Brain ; Dopamine ; Healthy Volunteers ; Humans ; Positron-Emission Tomography ; Serotonin ; Serotonin Plasma Membrane Transport Proteins*

BACKGROUND: Epoxy resin compounds are one of the common causes of occupational allergic contact dermatitis. In Korea, most cases of allergic contact dermatitis from epoxy resin compounds have been caused by the epoxy resin itself. We report a rare case of allergic contact dermatitis which was caused by epichlorohydrin, an ingredient of epoxy resin and 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP), a kind of hardeners. CASE REPORT: A 43-year-old man, who had worked at the epoxy resin glue manufacturing factory since 1999, presented with mild and intermittent erythematous papules and rashes on his face, neck, trunk, and both arms. He was dealing with epoxy resin, epichlorohydrin, bisphenol A and hardeners. After a new hardener was added in August 2008, his skin lesions worsened from what he had experienced in the past. A skin patch test was performed to identify the causative chemicals of the skin lesion. Epichlorohydrin and tris-DMP elicited positive reactions after 48 hours and increased after 96 hours. CONCLUSION: This case confirmed occupational allergic contact dermatitis caused by epichlorohydrin and tris-DMP, an ingredient of epoxy resin and a hardener, respectively.
Adhesives ; Adult ; Arm ; Benzhydryl Compounds ; Dermatitis, Allergic Contact ; Epichlorohydrin ; Exanthema ; Humans ; Korea ; Neck ; Patch Tests ; Phenols ; Skin

Background: In this study, the relationship between depression and stress-coping strategies among public enterprise workers whose workplaces were relocated to a newly-built innovation city was investigated. Methods: This study included a total of 922 public enterprise workers living in Naju Innovation City. Along with their sociodemographic data, each subject was assessed concerning depression, occupational stress, and stress-coping strategies using the Center for Epidemiologic Studies Depression Scale(CES-D), Korean Occupational Stress Scale (KOSS), and stress-coping scale (SCS), respectively. Logistic regression was performed to investigate the impact of the relevant factors on depressive symptoms. Results: The overall prevalence of depressive symptoms was 14%. Some sociodemographic variables, the total scores of the KOSS, and four subscales of the SCS revealed significant differences between the depressed and normal groups. Multivariate regression analysis revealed that the KOSS (odds ratio [OR], 1.17; p<0.001) and SCS, such as problem-solving-focused (OR, 0.75; p<0.001), emotion-focused (OR, 1.15; p<0.05), and wishful-thinking-focused (OR, 1.10; p<0.05), were significantly associated with depression. Conclusion The results indicated that depressive symptoms were highly prevalent among workers whose workplaces were relocated. In addition, these symptoms were found to be related with occupational stress and stress-coping strategies. Our findings also suggest that promoting healthy stress-coping strategies and reducing occupational stress may help in preventing the occurrence of depression and managing depressed workers.

BACKGROUND: The objective of this study was to compare the pharmacokinetics and safety between newly developed sildenafil (Please Orally Soluble Film) and sildenafil citrate (VIAGRA(R)) after single oral administration in healthy Korean male subjects. METHODS: A randomized, open-label, single dose, 2-way crossover study was conducted in 50 healthy male subjects. Each sequence group consisted of 25 subjects, received a single oral 50 mg dose of Please Orally Soluble Film (test formulation) or VIAGRA(R) (reference formulation) by study period. Blood samples were obtained during a 24-hour period after dosing. Sildenafil and its metabolite concentrations were determined using validated LC-MS/MS. A non-compartmental pharmacokinetic analysis was performed. Safety was assessed through monitoring of adverse events, vital sign check-up, physical examination, laboratory tests and electrocardiography. RESULTS: All enrolled participants completed the study. The point estimates and 90% confidence intervals of log transformed C(max) and AUC(last) of the test formulation in comparison to those of reference formulation were 0.9294(0.8353 - 1.0341) and 0.9415 (0.8869 - 0.9994) respectively. The analysis of variance showed no significant influences of formulation, sequence and period on the pharmacokinetic parameters. The frequencies of adverse events were not statistically different between the formulations. No serious adverse event was observed or reported. CONCLUSION: Please Orally Soluble Film could be considered bioequivalent to VIAGRA(R) and had similar safety properties in healthy Korean male subjects.
Administration, Oral ; Citric Acid ; Cross-Over Studies ; Humans ; Male ; Physical Examination ; Piperazines ; Purines ; Sulfones ; Sildenafil Citratea ; Vital Signs