Methylmercury is a hazardous substance that is of interest with regard to environmental health, as inorganic mercury circulating in the general environment is dissolved into freshwater and seawater, condensed through the food chain, ingested by humans, and consequently affects human health. Recently, there has been much interest and discussion regarding the toxicity of methylmercury, the correlation with fish and shellfish intake, and methods of long-term management of the human health effects of methylmercury. What effects chronic exposure to a low concentration of methylmercury has on human health remains controversial. Although the possibility of methylmercury poisoning the heart and blood vessel system, the reproductive system, and the immune system is continuously raised and discussed, and the carcinogenicity of methylmercury is also under discussion, a clear conclusion regarding the human health effects according to exposure level has not yet been drawn. The Joint FAO/WHO Expert Committee on Food Additives proposed to prepare additional fish and shellfish intake recommendations for consumers based on the quantified evaluation of the hazardousness of methylmercury contained in fish and shellfish, methylmercury management in the Korea has not yet caught up with this international trend. Currently, the methylmercury exposure level of Koreans is known to be very high. The starting point of methylmercury exposure management is inorganic mercury in the general environment, but food intake through methylation is the main exposure source. Along with efforts to reduce mercury in the general environment, food intake management should be undertaken to reduce the human exposure to methylmercury in Korea.
Animals ; *Environmental Exposure ; Fishes/metabolism ; Food Chain ; Humans ; Mercury Poisoning, Nervous System/etiology ; Methylmercury Compounds/chemistry/*metabolism/toxicity ; Neurons/drug effects ; Oxidative Stress/drug effects ; Public Health ; Reproduction/drug effects ; Thymocytes/cytology/drug effects

OBJECTIVES: This study was carried out to evaluate manganese exposure marker and the clinical significance of high signal intensity observed on brain magnetic resonance imaging(MRI) in mild steel/arc welders. METHODS: Brain MRI, blood and urinary manganese concentration measurements, physical and neurologic examinations, questionnaire and biochemistry were performed on 53 mild steel/arc welders(exposed group) and 112 non-manganese handling productive workers(control group). We calculated the pallidal index, the ratio of signal intensity of globus pallidus to subcortical frontal white-matter on sagittal 71-weighted MRI. And we studied the relationships between the pallidal index and other measurements. RESULTS: In 35(66.3%) exposed workers, high signal intensity were observed on the globus pallidus. Blood and urinary manganese levels were higher in exported group than control group. Pallidal index were significantly correlated with working duration, blood manganese level, urinary manganese level and positive rates of clinical symptoms and signs. CONCLUSIONS: The results of this study suggests that high signal intensity finding on brain MRI may be considered as useful tool for the evaluation of workers who have manganese exposure.
Biochemistry ; Brain* ; Globus Pallidus ; Magnetic Resonance Imaging* ; Manganese ; Neurologic Examination ; Questionnaires

No abstract available.
Chelating Agents* ; Lead Poisoning*

BACKGROUND: p27 is a member of the cyclin-dependent kinase (CDK) inhibitors that arrest the progression of the cell cycle; thus, it acts as a tumor suppressor gene. The loss or decrease of p27 protein is frequently seen and this has an independent prognostic potential for many human cancers. p27 is functionally inactivated through accelerated proteolysis and cytoplasmic sequestration. Cytoplasmic mislocalization of p27 by abnormal phosphorylation in the tumor cells doesn't allow it to bind and inhibit nuclear cyclin/CDK targets. METHODS: We examined the p27 protein expression in 86 cases of invasive ductal carcinoma of the breast via immunohistochemical staining to evaluate the subcellular localization of p27 and its relationship with the clinicopathologic features and the prognostic factors. RESULTS: The nuclear expression of p27 was noted in 48.9% of the tumors, a combined nuclear and cytoplasmic expression was noted in 20.9%, a cytoplasmic expression was noted in 12.8%, and a negative expression was noted in 17.4%. The decreased nuclear expression and/or cytoplasmic mislocalization of p27 were statistically correlated with the nuclear grade (p=0.001), histologic grade (p=0.036), tumor size (p=0.033), lymph node metastasis (p=0.043), ER (p=0.001), and PR (p=0.001) status, while they were not correlated with patient age, stage, HER2, p53, and Ki67. CONCLUSIONS: The breast tumors showing both decreased nuclear expression and cytoplasmic mislocalization of p27 are associated with a deranged cell cycle via functional inactivation and also with poor prognostic factors. It is expected that p27 can be a promising anticancer target molecule for the treatment of breast cancer.
Breast Neoplasms* ; Breast* ; Carcinoma, Ductal ; Cell Cycle ; Cyclin-Dependent Kinase Inhibitor p27 ; Cytoplasm ; Genes, Tumor Suppressor ; Humans ; Immunohistochemistry ; Lymph Nodes ; Neoplasm Metastasis ; Phosphorylation ; Phosphotransferases ; Prognosis ; Proteolysis

BACKGROUND: DNA methylation and histone modification are dynamically linked in the epigenetic control of gene silencing and they play an important role in tumorigenesis. METHODS: To evaluate the role of histone deacetylase 1 (HDAC1) in the development of lung cancer and the relationship between a HDAC1 overexpression and p16INK4a hypermethylation, we performed immunohistochemical staining for HDAC1 in 76 lung cancer specimens (39 squamous cell carcinomas and 37 adenocarcinomas) that had been previously evaluated for their p16INK4a methylation status by real-time quantitative polymerase chain reaction. RESULTS: A HDAC1 overexpression (>50% of HDAC1 immunoreactive cells) was detected in 65 (85.5%) out of the 76 cases and it was more frequently seen in the squamous cell carcinomas (97.4%) than in the adenocarcinomas (73.0%) (p=0.002). The incidence of HDAC1 overexpression tended to be higher in the heavy smokers with more than 20 pack-years (p=0.067). Although there was no statistical significance, the frequency of p16INK4a hypermethylation in the cases with a HDAC1 overexpression (27.7%) tended to be higher than that in the cases without a HDAC1 overexpression (9.0%) (p=0.175). CONCLUSIONS: A HDAC1 overexpression might be involved in lung carcinogenesis, and especially in a subgroup of smoking and squamous cell carcinoma patients, and a HDAC1 overexpression may be associated with p16INK4a hypermethylation.
Adenocarcinoma ; Carcinoma, Squamous Cell ; Cell Transformation, Neoplastic ; Cyclin-Dependent Kinase Inhibitor p16 ; DNA Methylation ; Epigenomics ; Gene Silencing ; Genes, p16 ; Histone Deacetylase 1 ; Histone Deacetylases ; Histones ; Humans ; Incidence ; Lung ; Lung Neoplasms ; Methylation ; Polymerase Chain Reaction ; Smoke ; Smoking

We experienced a case of nephropathy in chronic lead poisoning. The patient was 43-year-old male who has been working in secondary lead smelting plant for ]4 years. On admission, blood pressure was 160/90 mmHg and the others were non-specific. In past history, he received chelating agent administration for lead poisoning irregularly and medicated for gout, and the blood lead concentration was 180.0 microgram/dl on 2 months before admission. Smoking habit has been 1 pack per day for 15 years and drinking habit has been 1 bottle of Soju per day but less now. In liver function test, AT/ALT were 27/28 IU/l and gamma-GT was 456 IU/l. In blood test, Hb:11. 5 g/dl , Hct: 34.0% and basophilic stipplings were found in peripheral blood smear. Chest PA was normal and abdominal ultrasonographic finding was non-specific except fatty liver. In the test of lead exposure indices, pbB: 83.0 microgram/dl, pbU: 28.3 microgram/l, and blood ZPP was 300.0 microgram/dl. And in renal function test, BUN: 31.4 mg/dl, blood creatinine: 2.7mg/dl, blood uric acid: 9.1 mg/dl, urinary albumin: 100.0 mg/g creatinine, urinary a alpha 1-microglobulin: 120.5 mg/g creatinine, urinary beta2-mioroglobulin: 183.8 microgram/g creatinine, and 24 hours urinary creatinine clearance was 31.9 ml/min. The ultasonoguided renal biopsy showed the global sclerosis of glomerulus, moderate atrophy and loss of tubule, and interstitial fibrosis in light microscopy. There were diffuse losses of brush border of proximal tubule in electronmicroscopy.
Adult ; Atrophy ; Basophils ; Biopsy ; Blood Pressure ; Creatinine ; Drinking ; Fatty Liver ; Fibrosis ; Gout ; Hematologic Tests ; Humans ; Lead Poisoning* ; Liver Function Tests ; Male ; Microscopy ; Microvilli ; Osmeriformes ; Plants ; Sclerosis ; Smoke ; Smoking ; Thorax ; Uric Acid

BACKGROUND: Nicotine dependence and its severity are often determined by individuals’ psychosocial factors.This study purposed to analyze how Korean workers’ job stress is related with their nicotine dependence according to demographic and occupational characteristics in order to reduce smoking related to job stress and to establish objective indicators to be used in developing adequate smoking cessation strategies. METHODS: The subjects of this study were 4,639 workers who replied to the questionnaire survey. In addition, 1,948 current smokers were separated from non-smokers and ex-smokers, and the relationship between job stress and nicotine dependence was analyzed with the current smoker group. Nicotine dependence was tested using Fagerström’s Test of Nicotine Dependence, and stress was measured using a questionnaire on subjective stress felt by workers in their daily life and the short form of the Korean Occupational Stress Scale. RESULTS: The smoking rate was 54.1 % among men and 2.5 % among women. Nicotine dependence was significantly different according to interpersonal conflict, organization system and lack of reward (p < 0.05). As multivariate logistic analysis, job control, occupational climate and total stress score were statistical significant (p < 0.05). CONCLUSIONS: Job stress was found to be related with smoking status and nicotine dependence. Based on this result, it is suggested to enhance workers’ welfare for health promotion in workplace by improving their working environment in order to reduce job stress and consequently to decrease the smoking rate.
Climate ; Female ; Health Promotion ; Humans ; Male ; Nicotine* ; Reward ; Smoke ; Smoking ; Smoking Cessation ; Tobacco Use Disorder*

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.
Arsenic/*analysis ; Cosmetics/chemistry ; Drinking Water/chemistry ; *Environmental Exposure ; Humans ; Particulate Matter/chemistry ; Smoking ; Water Pollutants, Chemical/*analysis

Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.
Arsenic/*toxicity/urine ; Cardiovascular Diseases/chemically induced ; *Environmental Exposure ; Environmental Pollutants/*toxicity ; Female ; Humans ; Male ; Neoplasms/chemically induced ; Reproduction/drug effects

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.
Arsenic/*analysis ; Cosmetics/chemistry ; Drinking Water/chemistry ; *Environmental Exposure ; Humans ; Particulate Matter/chemistry ; Smoking ; Water Pollutants, Chemical/*analysis