IgA nephropathy in a laboratory worker that progressed to end-stage renal disease

Bokki Min,Gyuree Kim,Taesun Kang,Chungsik Yoon,Sung-il Cho,Domyung Paek 대한직업환경의학회 2016 대한직업환경의학회지 Vol.28 No.-

Background: IgA nephropathy (IgAN) is the most common form of glomerulonephritis, a principal cause of end-stage renal disease (ESRD) worldwide. The mechanisms of onset and progression of IgAN have not been fully revealed, and epidemiologic studies have yielded diverging opinions as to the role of occupational exposure to organic solvents in the initiation or worsening of IgAN. As the authors encountered a laboratory worker with IgAN that progressed to ESRD, we present a case report of IgAN progression due to dichloromethane exposure along with a review of literature. Case presentation: A 41-year-old male laboratory worker began to experience gross painless hematuria after two years of occupational exposure to toluene. Although clinical follow-up was initiated under the impression of IgAN based on clinical findings, the patient continued to work for four more years in the same laboratory, during which he was in charge of laboratory analysis with direct exposure to a high concentration of dichloromethane without proper protective equipment. During that time, his renal function rapidly worsened and finally progressed to ESRD 10 years after the first clinical symptoms. The result of exposure assessment through reenactment of his work exceeded the occupational exposure limit for dichloromethane to a considerable degree. Conclusions: The causal association between occupational solvent exposure and IgAN is still unclear; therefore, this case report could be used as a basis to support the relevance of occupational solvent exposure to IgAN and/or its progression. Early intervention as well as close monitoring of laboratory workers exposed to various organic solvents is important to prevent or delay the progression of glomerulonephritis to ESRD in the occupational setting.

사장교 주탑부 이중 가물막이 가시설 및 기초 지반처리 설계

민복기(Min, Bokki),김광표(Kim, Kwangpyo),주광수(Joo, Gwangsu) 대한토목학회 2021 대한토목학회 학술대회 Vol.2021 No.10

DPSS UV laser를 이용한 롤 금형 미세가공

민복기(Bokki Min),김재구(Jaegu Kim),조성학(Sunghak Cho),최두선(Doosun Choi),황경현(Kyunghyun Whang) 한국레이저가공학회 2008 한국레이저가공학회 학술대회 논문집 Vol.2008 No.-

This paper presents the method to fabricate a roll mold with microstructure using DPSS(diode pumped solid-states) UV laser. DPSS laser ablation makes it possible to micromachine by controlled energy density and pulse repetition rate of laser. But, In case of metal ablation, molten debris is caused by thermal damage. Hence, We suggest the process of the ablation of a photoresist(PR) coated on roll mold. And we design a roll coater for laminating the photoresist onto the curby surface of a copper roll mold. The microstructure on roll mold is fabricated by controlled laser pulse energy, pulse repetition rate, rotation speed and rotation number of roll. We compare and analyze the quality of microstructure by the wet etching process with the quality by the direct write process.

The association of relational and organizational job stress factors with sleep disorder

Gyuree Kim,Bokki Min,Jaeyoup Jung,Domyung Paek,Sung-il Cho 대한직업환경의학회 2016 대한직업환경의학회지 Vol.28 No.-

Background: Sleep disorder is a disease that causes reduction in quality of life and work efficiency of workers. This study was performed to investigate the relationship between job-related stress factor and sleep disorder among wageworkers in Korea. Methods: This study was based on analysis of the 3rd Korean working conditions survey. We analyzed 35,902 workers whose employment status is wageworker. We classified the job-related stress factor into 12 sections. Logistic regression was performed to estimate the relationship between job-related stress factor and sleep disorder and Odds ratio and 95 % CI were calculated using the SPSS version 23.0 program. Results: Many categories of Job-related stress factor were correlated with sleep disorder (8 of 12 for women, 10 of 12 for men). The results of the regression analysis, corrected for general and occupational characteristics, indicated that sleep disorder was significantly correlated with the following categories of job-related stress: discrimination experience (OR 3.37, 95 % CI = 2.49 ~ 4.56 in women, OR 1.96, 95 % CI = 1.53 ~ 2.51 in men), direct customer confrontation (OR 2.72, 95 % CI = 1.91 ~ 3.86 in women, OR 1.99, 95 % CI = 1.45 ~ 2.72 in men), emotional stress (OR 2.01, 95 % CI = 1.30 ~ 3.09 in men), work dissatisfaction (detailed) (OR 1.99, 95 % CI = 1.36 ~ 2.93 in men), work dissatisfaction (overall) (OR 2.30, 95 % CI = 1.66 ~ 3.20 in women, OR 2.40, 95 % CI = 1.88 ~ 3.08 in men), expression of opinion difficulty (OR 0.66, 95 % CI = 0.48 ~ 0.92 in women, OR 0.57, 95 % CI = 0.45 ~ 0.73 in men). Conclusion: A number of studies have reported that stress affects sleep disorder. In this study, many factors suspected to increase the risk of sleep disorder were added to previously known job stress factors. In particular, this study found a strong correlation between work-associated sleep disorder and relational and organizational job stress factors. Sleep disorder may lead to large decreases in workers’ quality of life and work efficiency. Awareness and interventions are therefore required to reduce workplace stress; additional research of this topic is also required.

Method for Synthesis of Tetrabenzoporphyrin Precursor for Use in Organic Electronic Devices

Jeong, Seung-Doo,Min, Bokki,Cho, Song Yun,Lee, Changjin,Park, Bo Keun,An, Ki-Seok,Lim, Jongsun American Chemical Society 2012 Journal of organic chemistry Vol.77 No.18

<P>We developed a new synthetic method for bicyclo[2.2.2]octadiene (BCOD)-fused porphyrin (<B>1</B>), a tetrabenzoporphyrin (TBP, <B>2</B>) precursor that is well-known as a good material for use in organic electronic devices. The newly developed method synthesizes the BCOD-fused pyrrole intermediate (which is the most important intermediate in synthesizing BCOD-fused porphyrin) in a simpler and easier manner than other existing methods, and thus, the new method can efficiently synthesize the TBP precursor.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/joceah/2012/joceah.2012.77.issue-18/jo300831u/production/images/medium/jo-2012-00831u_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jo300831u'>ACS Electronic Supporting Info</A></P>

Li₂CO₃ 첨가에 의한 BaSr(TiO₃)의 저온 소결과 가변유전 특성

김인성(Insung Kim),민복기(Bokki Min),정순종(Soonjong Jeong),송재성(Jaesung Song),전소현(Sohyun Jeon) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.10

(BaSr)TiO₃ thick films were prepared by tape casting method using BaTiO₃ and SrTiO₃ powder slurry in order to investigate dielectric properties and low temperature sintering. Sintering density was 5.7 g/㎤ and the BST sample exhibited the maximum dielectric constant, tunability at temperatures near phase transition point. The dielectric constant was increased and curie temperature was shifted to higher temperature with increasing of annealing temperature.

Effect of Long Working Hours on Self-reported Hypertension among Middle-aged and Older Wage Workers

Dong Hyun Yoo,Mo-yeol Kang,Domyung Paek,Bokki Min,Sung-il Cho 대한직업환경의학회 2014 대한직업환경의학회지 Vol.26 No.-

Objectives: Many studies have reported an association between overwork and hypertension. However, research on the health effects of long working hours has yielded inconclusive results. The objective of this study was to identify an association between overtime work and hypertension in wage workers 45 years and over of age using prospective data. Methods: Wage workers in Korea aged 45 years and over were selected for inclusion in this study from among 10,254 subjects from the Korean Longitudinal Study of Ageing. Workers with baseline hypertension and those with other major diseases were excluded. In the end, a total of 1,079 subjects were included. A Cox proportional hazards model was used to calculate hazard ratios and adjust for baseline characteristics such as sex, age, education, income, occupation, form of employment, body mass index, alcohol habit, smoking habit, regular exercise, and number of working days per week. Additional models were used to calculate hazard ratios after gender stratification. Results: Among the 1,079 subjects, 85 workers were diagnosed with hypertension during 3974.2 person-months. The average number of working hours per week for all subjects was 47.68. The proportion of overtime workers was 61.0% (cutoff, 40 h per week). Compared with those working 40 h and less per week, the hazard ratio of subjects in the final model, which adjusted for all selected variables, working 41-50 h per week was 2.20 (95% confidence interval [CI], 1.19?4.06), that of subjects working 51-60 h per week was 2.40 (95% CI, 1.07?5.39), and that of subjects working 61 h and over per week was 2.87 (95% CI, 1.33?6.20). In gender stratification models, the hazard ratio of the females tended to be higher than that of the males. Conclusion: As the number of working hours per week increased, the hazard ratio for diagnosis of hypertension significantly increased. This result suggests a positive association between overtime work and the risk of hypertension.