• Toxicological Research
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• v.28 no.4
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• pp.269-277
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• 2012

The purpose of this study was to understand the mechanism of cardiovascular disease (CVD) caused by exposure to hazardous chemicals. We investigated changes in the symptoms of metabolic syndrome, which is strongly related to CVD, and in levels of other CVD risk factors, with a special emphasis on the roles of catecholamines and oxidative stress. The results revealed that neither body mass index (BMI) nor waist and hip circumferences were associated with exposure to hazardous chemicals. Among metabolic syndrome criteria, only HDL-cholesterol level increased on exposure to hazardous chemicals. Levels of epinephrine (EP) and norepinephrine (NEP) were not influenced by exposure to hazardous chemicals; however, the total antioxidative capacity (TAC) reduced because of increased oxidative stress. Both hazardous chemical exposure level and metabolite excretion were related to EP, NEP, and the oxidative stress index (OSI). Logistic regression analysis with these factors as independent variables and metabolic syndrome criteria as dependent variables revealed that EP was associated with blood pressure, and NEP with metabolic syndrome in the chemical-exposed group. In conclusion, the results suggest that reactive oxygen species generated and oxidative stress due to exposure to hazardous chemicals act as mediators and cause changes in the physiological levels of EP and NEP to increase blood pressure. This ultimately leads to the development of CVD through increase in cholesterol, triglyceride, and blood glucose levels by lipid peroxidation.

• Molecular & Cellular Toxicology
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• v.5 no.4
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• pp.310-316
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• 2009

Some environmental chemicals have been shown to cause liver-toxicity as the result of bioaccumulation. Particularly, fungicides have been shown to cause varying degrees of hepatictoxicity and to disrupt steroid hormone homeostasis in in vivo models. The principal objective of this study was to evaluate the liver-toxic responses of environmental chemicals-in this case selected fungicides and parasiticides-in order to determine whether or not this agent differentially affected its toxicogenomic activities in hepatic tumor cell lines. To determine the gene expression profiles of 3 fungicides (triadimefon, myclobutanil, vinclozolin) and 1 parasiticide (dibutyl phthalate), we utilized a modified HazChem human array V2. Additionally, in order to observe the differential alterations in its time-dependent activities, we conducted two time (3 hr, 48 hr) exposures to the respective IC20 values of four chemicals. As a result, we analyzed the expression profiles of a total of 1638 genes, and we identified 70 positive significant genes and 144 negative significant genes using four fungicidic and parasiticidic chemicals, using SAM (Significant Analysis of Microarray) methods (q-value<0.5%). These genes were analyzed and identified as being related to apoptosis, stress responses, germ cell development, cofactor metabolism, and lipid metabolism in GO functions and pathways. Additionally, we found 120 genes among those time-dependently differentially expressed genes, using 1-way ANOVA (P-value<0.05). These genes were related to protein metabolism, stress responses, and positive regulation of apoptosis. These data support the conclusion that the four tested chemicals have common toxicogenomic effects and evidence respectively differential expression profiles according to exposure time.

• Korean Journal of Occupational Health Nursing
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• v.21 no.3
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• pp.192-200
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• 2012

Purpose: The purpose of this study aimed to investigate job stress levels of occupational health managers and whether job stress levels were affected by various factors such as size and types of company and work-related characteristics of occupational health managers. Methods: The study was conducted from May to September 2011 in the chemicals manufacturing factories in Korea and total subjects were 59 occupational health managers. We measured job stress levels of occupational health managers using Korean occupational stress scale (KOSS) questionnaires and the information of company characteristics was obtained using a self-reported questionnaire. Results: The characteristics of company such as type, size and industries and job characteristics of occupational health managers were significant factors in job stress. Job demand, job control, job insecurity, organizational system and occupational environment scores were significantly associated with type, size and industries of company. In multiple regression analyses, we found that job demand was significantly associated with occupational position and type of company, and job insecurity was significantly associated with working hour. Also, we found that lack of reward was significantly associated with education level, speciality, duration of work and hour and type of company. Conclusion: These results indicate that job stress of occupational health managers is significantly associated with work-related characteristics and company's characteristics.

• Women's Health Nursing
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• v.25 no.4
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• pp.423-433
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• 2019

Purpose: The study aimed to examine the effects of sleep pattern, stress, and attitude towards menstruation, and behavior that causes a reduction in exposure to endocrine disrupting chemicals (EDCs) in the course of premenstrual syndrome (PMS) in female adolescents. Method: In total, 200 girls attending middle school in K city were recruited via convenience sampling between December 11 and 31, 2018, and 192 subjects were selected for the analysis. Data were analyzed using descriptive statistics, an independent t-test, ANOVA, Pearson's correlation coefficient, and multiple regression. Results: Overall, 9 (4.7%), 152 (79.2%), and 31 (16.1%) students had morning-, intermediate-, and evening-type sleep pattern, respectively. The mean scores for school-related stress were highest. Scores for stress regarding relationships with friends were the lowest. The mean score for attitudes toward menstruation was 72.33 out of 147. The mean score for behavior that led to a reduction in EDCs exposure was 56.57 out of 85. The mean scores for PMS severity were 25.30 and 38.39 out of 60. Analysis of factors affecting PMS revealed that severity of menstrual pain (β=.28), use of analgesics during menstruation (β=.17), family history of PMS (β=-.16), stress (β=.19), and behavior that reduces EDCs exposure (β=-.17) exerted significant effects on PMS. The explanatory power of these variables was 37%. Conclusion: The findings propose the necessity of a health intervention program including educational information, which can reduce PMS in adolescents, induce the behaviors which can decrease exposure to EDCs, and activities for managing the stress levels.

• Toxicological Research
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• v.23 no.3
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• pp.207-214
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• 2007

Chronic oxidative stress produced by exposure to environmental chemicals or pathophysiological states can lead animals to aging, carcinogenesis and degenerative diseases. Indirect antioxidative mechanisms, in which natural or synthetic agents are used to coordinately induce the expression of cellular antioxidant capacity, have been shown to protect cells and organisms from oxidative damages. Electrophile and free radical detoxifying enzymes, which were originally identified as the products of genes induced by cancer chemopreventive agents, are members of this protective system. The NFE2 family transcription factor Nrf2 was found to govern expression of these detoxifying enzymes, and screening for Nrf2-regulated genes has identified many gene categories involved in maintaining cellular redox potential and protection from oxidative damage as Nrf2 downstream genes. Further, studies using Nrf2-deficient mice revealed that these mutant mice showed more susceptible phenotypes towards exposure to environmental chemicals/carcinogens and in oxidative stress related disease models. With the finding that cancer chemopreventive efficacy of indirect antioxidants (enzyme inducers) is lost in the absence of Nrf2, a central role of Nrf2 in the antioxidative protective system has been firmly established. Promising results from cancer prevention clinical trials using enzyme inducers propose that pharmacological interventions that modulate Nrf2 can be an effective strategy to protect tissues from oxidative damage.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.438-447
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• 2011

Deinococcus radiodurans is extremely resistant to various genotoxic conditions and chemicals. In this study, we characterized the effect of a sublethal concentration (100 ${\mu}M$) of cadmium (Cd) on D. radiodurans using a whole-genome DNA microarray. Time-course global gene expression profiling showed that 1,505 genes out of 3,116 total ORFs were differentially expressed more than 2-fold in response to Cd treatment for at least one timepoint. The majority of the upregulated genes are related to iron uptake, cysteine biosynthesis, protein disulfide stress, and various types of DNA repair systems. The enhanced upregulation of genes involved in cysteine biosynthesis and disulfide stress indicate that Cd has a high affinity for sulfur compounds. Provocation of iron deficiency and growth resumption of Cd-treated cells by iron supplementation also indicates that CdS forms in iron-sulfur-containing proteins such as the [Fe-S] cluster. Induction of base excision, mismatch, and recombinational repair systems indicates that various types of DNA damage, especially base excision, were enhanced by Cd. Exposure to sublethal Cd stress reduces the growth rate, and many of the downregulated genes are related to cell growth, including biosynthesis of cell membrane, translation, and transcription. The differential expression of 52 regulatory genes suggests a dynamic operation of complex regulatory networks by Cd-induced stress. These results demonstrate the effect of Cd exposure on D. radiodurans and how the related genes are expressed by this stress.

• Journal of Plant Biotechnology
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• v.31 no.1
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• pp.83-88
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• 2004

Expression of an anionic peroxidase swpa2 gene isolated from cultured cells of sweetpotato (Ipomoea batatas) was investigated under various stress conditions by RT-PCR. The swpa2 gene was not expressed in any tissues of intact sweetpotato plant grown at the normal condition. The expression of this gene was strongly induced in leaf tissue by treatment of $H_2O$$_2$ (440mM). Treatment of NaCl (100mM), ABA (0.1mM) and methyl jasmonate(MeJA, 0.1mM) also induced the expression of swpa2 gene. Interestingly, salicylic acid (SA, 0.1 mM) did not induce the expression of swpa2 gene, indicating that anionic swpa2 POD is differently involved in SA and MeJA signaling pathways. In addition, swpa2 gene was strongly induced in sweetpoato leaf tissues infected with Pectobacterium chrysanthemi, indicating that swpa2 is involved in defense related to the pathogenesis of P. chrysanthemi in sweetpotato plants. These results strongly suggest that swpa2 gene is involved in overcoming oxidative stresses caused by both abiotic and biotic stress.

• Korean Journal of Occupational Health Nursing
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• v.15 no.2
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• pp.144-152
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• 2006

Purpose: This study was conducted to understand the effects of daily hassle stress on the psycho-social health of male workers in manufacturing industry. Methods: Daily hassle stress and psycho-social health in manufacturing industry workers were estimated by using the Daily Hassles Scale for Korea Workers (DHS-KW) and general health questionnaire (GHQ), respectively. Results: The subjects were 553 male workers who had never been occupationally exposed to hazardous chemicals, were mean age 39.6 years and mean work duration was 15.66 years. DHS-KW total mean score had significantly higher in young ages (twenties and thirties ages), office workers, managers and daytime workers than other groups. GHQ total mean scores were significantly higher in un-married, daytime and overtime workers than others. DHS-KW and GHQ score correlated that they were negative correlation with age and working years, but was positive correlation with working hours and overtime work. The significant correlation between DHS-KW and GHQ were observed almost variables of DHS-KW and GHQ except a domestic and daily problem in DHS-KW variables. Domestic and daily problems were only significantly correlated with anxiety and insomnia of GHQ variables. Conclusion: This study indicated that physical health was associated with work condition and psychsocial health was mainly associated with domestic and daily problems of DHS-KW variables. Thus, the study on Daily Hassles stress and related with work stress should be further investigated for the comprehensive health program including stress management and coping behavior.

• Korean Journal of Occupational Health Nursing
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• v.15 no.2
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• pp.133-143
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• 2006

Purpose: The purpose of this study was to examine the relationship between perceived job stress and work environmental factors related with socioeconomics factors and physical burden in the golf caddies. Methods: Job stress in golf caddies was estimated by using the Karasek's job content questionnaire (JCQ) and work environmental factors were estimated by self-reported questionnaire and interview. Results: The subjects were 316 woman caddies who had never been occupationally exposed to hazardous chemicals, was mean age 31.1 years. Mean work duration was 6.44 years and working hours per day on low- and high-demand season were 6.16 and 10.51, respectively. The golf caddies displayed higher scores of job stress due to multiple factors such as working hours and frequency of rounding per week, physical burden, confliction, income satisfaction and employment stability. We found that high strain group was positive correlation with age, career, working hour (including frequency of rounding) and job demand, however, showed negative correlation with job decision latitude and support of supervisor and coworker. Conclusion: In conclusion, we suggest that the golf caddies be regard divided into high strain group as appropriate. Thus, stress management and health promotion program for golf caddies should be developed.

• Development and Reproduction
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• v.26 no.4
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• pp.155-163
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• 2022

Human pluripotent stem cells (hPSCs) can give rise to a vast array of differentiated derivatives, which have gained great attention in the field of in vitro toxicity evaluation. We have previously demonstrated that hPSC-derived alveolar epithelial cells (AECs) are phenotypically and functionally similar to primary AECs and could be more biologically relevant alternatives for assessing the potential toxic materials including in fine dust and cigarette smoking. Therefore, in this study, we employed hPSC-AECs to evaluate their responses to exposure of various concentrations of diesel particulate matter (dPM), cigarette smoke extract (CSE) and nicotine for 48 hrs in terms of cell death, inflammation, and oxidative stress. We found that all of these toxic materials significantly upregulated the transcription of pro-inflammatory cytokines such as IL-1α, IL-β, IL-6, and TNF-α. Furthermore, the exposure of dPM (100 ㎍/mL) strongly induced upregulation of genes related with cell death, inflammation, and oxidative stress compared with other concentrations of CSE and nicotine. These results suggest that hPSC-AECs could be a robust in vitro platform to evaluate pulmotoxicity of various air pollutants and harmful chemicals.