전자부품 제조업 근로자들의 시력변화에 대한 연구

이용만,안규동,이성수,함정오,김화성,리갑수,이병국 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

근접작업이 시력약화의 원인이 될 수 있는가를 알아보기 위하여 전자부품을 제조하는 2개 사업장에서 1991년에서 1993년까지 입사한 근로자들 중에서 근접작업으로 인정되는 마이크로칩을 조립하는 근접작업자 306명을 조사군으로, 대조군은 세탁기 타이머 및 일반 기계기구를 조립하는 작업자 154명, 계 460명을 선정하였다. 이들 대상자는 1991년 입사자는 1993, 1994, 1995년 시력을 조사하였으며, 1992년 입사자는 1993, 1994, 1995년 3년동안 조사를 하였으며, 1993년 입사자는 1994, 1995년 2년간 시력을 조사하였다. 대상자 중에서 입사시 안경을 착용한 근로자는 82명(17.8%)이었다. 따라서 남자 근로자와 안경착용자를 제외한 여성 근로자들 335명만을 추적 조사하여 다음과 같은 결론을 얻었다. 조사군에서 입사시 시력 1.0 이상이었던 근로자의 분포는 취업 1년 후 약 25-35% 정도 감소하였으며, 2년후에는 약 40-60% 정도의 감소를 나타내었고, 3년 후 약 50-65% 정도로 감소하였고 4년후에는 약 65% 이상 감소하였다. 그러나 대조군에서는 1.0 이상의 시력을 보였던 근로자들의 비율이 취업 1년 또는 2년 후 15-30%의 감소를 보이고 있으나 그 이후에는 큰 변동이 없었다. 이들의 시력변화를 근무년수에 따라 알아보기 위하여 조사된 시력을 순위변수로 하여 Kruskall-Wallis 검정을 시행한 결과 조사군, 대조군 모두에서 근속년수에 따른 순위의 합의 평균이 년차적으로 유의하게 감소하였으나, 입사시부터 근속년수에 따른 조사군과 대조군과의 순위합의 평균에 의한 시력차 비교에서 입사시 조사군의 순위합의 평균이 유의하게 높았던 것이 근무기간에 따라 대조군의 평균이 높아지면서 통계적 유의성이 없고 대체적으로 1년 이후부터 변화가 적은 것으로 나타나 근접작업으로 인한 시력약화를 추정할 수 있었다. This study was carried out to investigate that the close distance works were associated with decreased visual acuity. 306 workers were subjects who had been recruited from 1991 to 1993 in two electronic parts manufacturing factories, and 154 workers were controls who had been employed from 1991 to 1993 in launder machine timer and general machine assembly factories. Subjects who had been employed in 1991 and 1992 were follow up from 1993 to 1995, and subjects who had been employed in 1993 were from 1994 to 1995. The male workers as well as glasses wearing workers were excluded. Only 335 female workers were followed up to study the change of visual acuity. The results were as follows; The rate of workers with visual acuity over 1.0 at recruit year in subjects group was decreased about 25-35% after 1 year, 40-60% after 2 years, 50-65% after 3 years, and 65% after 4 years. While, the rate of workers with visual acuity over 1.0 at recruit year in control group was decreased about 15-30% after 1 or 2 years, and there was no more additional visual acuity reduction after then. Kruskall-Wallis test was performed to investigate the change of visual acuity in subject and control group by work duration. The means scores of ranks in both group were significantly decreased by work duration. The mean scores of ranks in subject group at recruit year were significantly higher than those in control group at recruit year, but these differences were disappeared after 1 year work. Therefore, this suggest that close distance workers may be affected their visual acuity.

생약제제인 이공산(異功散)의 Cisplatin 유도 신장독성 보호 및 항산화 효과

Lee, Kyung-Tae,Ahn, Kyoo-Seok,Chang, Sung-Goo,Oh, Soo-Myung,Jung, Jee-Chang 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Kyung-Tae Lee, Kyoo-Seok Ahn¹, Sung-Goo Chang², Soo-Myung Oh²and Jee-Chang Jung²¹College of Pharmacy, ²Oriental Medicine and ³College of Medicine, and East-West Medical Reserch Institute, Kyung Hee University, Seoul, Korea. Preventive and Antioxidative Effects of Crude Drug Preparation(E-kong-san) on Cisplatin Induced Nephrotoxicity. Proceedings of International Symposium on East-West Medicine, Seoul. 201-211, 1999. -Nephroprotective effects of a crude drug-prearation (E-kong-san) were determined from cisplatin on rabbit kidney proximal tubule and human renal cortical cells by MTT assays and sustained glucose consumption on ciplatin-induced human renal cortical tissue. Levels of creatinine and blood ure nitrogen(BUN) in serum after administration of cisplatin(0.75mg/kg,i.p.) to E-kong-san(0.75g/kg/day,p.o.)-pretreated rats were markedly lower compared to those of cisplatin-treated rats. Moreover, the administration of E-kong-san significantly inhibited the loss of body weight of cisplatin injected rts. These findings suggest that E-kong-san on the cisplatin induced nephrotoxicity led us to investigate whether the effect of this water extract was a result of anti-oxidation. E-kong-san showed strong free radical scavenger activities on 1,1-dipheny1-2picrylhydrazil(DPPH) radical and xanthine/xanthine oxidase(XOD) generated superoxide anion radical(O2-). We further studied the effects of E-kong-san on lipid peroxidation in rat liver microsomes induced by enzymatic and nonenzymatic methods. E-kong-san exhibited significant inhibition on both ascorbic acid/Fe2+and ADP/NADPH/Fe3+ induced lipid peroxidation in rat liver microsomes. Based on these results, we suggest that-E-kong-san attenuate the cisplatin induced cytotoxicity and its mechanism can be eplained by antioxidant.

연작업자들에서의 δ -aminolevulinic acid dehydratase 유전형질의 다형성이 신기능에 미치는 영향

안익수,황보영,김용배,리갑수,이성수,장봉기,함정오,안규동,이병국 순천향대학교 산업의학연구소 2001 순천향산업의학 Vol.7 No.1

δ-aminolevulinic acid hehydratase (ALAD) is a polymorphic enzyme that has two alleles, ALAD1 (ALAD1-1 as phenotype) and ALAD2 (ALAD1-2 or ALAD2-2 as phenotype). ALAD genotype has been reported to modify the toxicokinetics of lead. To investigate the influence of ALAD genotype polymorphism on renal function in lead workers, author studied 1022 male lead workers and 149 non lead workers in the same industries. For the cross-sectional renal function indices, blood urea nitrogen (BUN), serum creatinine, uric acid and total protein were selected. Blood lead and blood zinc protoporphyrin were also measured as indices of lead exposure. Information on weight, age, job duration, smoking & drinking history were collected. Following results are as follows: 1. Whereas the mean (standard deviation) of blood lead and blood ZPP of lead workers were 27.2±12.5 ㎍/㎗ and 57.7±37.8 ㎍/㎗, those of non-lead workers in the same premises were 14.9±6.5 ㎍/㎗ and 44.6± 15.8 ㎍/㎗ respectively. The difference of mean blood lead and blood ZPP between two groups were statistically significant. 2. Whereas the prevalence of the variant allele, ALAD2 in 1022 lead workers was 10.2 %, the prevalence of that in 149 non-lead workers was 7.4 %. But there was no difference of prevalence between two groups. 3. The mean±standard deviation of blood lead of subjects with ALAD1 was 25.5± 12.7 ㎍/㎗ and was slightly lower than that of subjects with ALAD2 (26.5±10.9 ㎍/㎗), and the mean±standard deviation of blood ZPP of subjects with ALAD1 was slightly higher than that of subjects with ALAD2 (56.7±37.3 ㎍/㎗ vs 48.9±18.6 ㎍/㎗). But the differences of blood lead and blood ZPP between two genotypes were not statistically significant. 4. There were no differences of cross-sectional renal function indices (BUN, serum creatinine, uric acid and total protein) either by lead workers and non-lead workers or two genotypes. 5. In multiple regression analysis of ALAD genotype on BUN after controlling for possible confounders (sex, weight, job duration, smoking and drinking status), the mean of BUN in ALAD2 subjects was 0.629 ㎎/㎗ lower than ALAD1 subjects with a weak statistical significance (p=0.07). But in logistic analysis of ALAD genotype on median value of BUN revcaled that subjects of ALAD2 genotype were 32% less likely to have median value or more of BUN than subjects of ALAD1 with odd ratio of 0.618 (95% confidence interval 0.411-0.920). 6. In multiple regression analysis of ALAD genotype on serum creatinine after controlling for possible confounders (sex, weight, job duration, smoking and drinking status), the mean of serum creatinine in ALAD2 subjects was 0.0271 ㎎/㎗ lower than ALAD1 subjects with statistical significance (p=0.02). On the other hand, in logistic analysis of ALAD genotype on median value of serum creatinine revealed that subjects of ALAD2 genotype were 30% less likely to have median value or more of scrum creatinine than subjects of ALAD1 with odd ratio of 0.700 (95% confidence interval 0.442-1.080). With the above results, it was found that the variant allcle, ALAD2 appeared to modify the association of lead and renal function and ALAD2 genotype may be supportive for the protective effect of lead.

2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

Method for Protection of Single‑Line‑Ground Fault of Distribution System with DG Using Distance Relay and Directional Relay

Jung‑Hun Lee,Min‑Su Park,Hong‑Seon Ahn,Kyung‑Won Park,Jun‑Seok Oh,Seung‑Gyu Jeon,Dong‑Kyu Kim,Jae‑Eon Kim 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

When large scales DG are connected to the distribution system of unidirectional power currents, bi-directional power currents are formed, making it impossible to use conventional overcurrent protection methods alone to detect and isolate fault sections for ground and short-circuit faults. To solve these problems, this study proposed the method of protection against single-line-ground fault of common neutral line multi-contact local power distribution system using distance relay and directional relay. The proposed protection method was applied to the common neutral multi-ground distribution system to validate the protection against single-line-ground fault through the PSCAD/EMTDC software package and efectively detect and isolate only the zone of single-line-ground fault without malfunctions.

새로운 연노출의 효과지표로서의 혈장 δ-aminolevulinic acid 측정의 유용성

이금원,황보영,김용배,리갑수,이성수,장봉기,함정오,안규동,이병국 순천향대학교 산업의학연구소 2001 순천향산업의학 Vol.7 No.1

To evaluate the usefulness of the measurement of plasma δ - aminolevulinic acid (ALAP) as a new effect indicator of lead exposure, the association of ALAP with blood lead, DMSA chelatable lead and bone lead with a special emphasis of genetic interaction of ALAD polymorphism was studied with 419 lead exposed workers and 85 non-lead exposed workers. Lead workers were recruited from storage battery industries, secondary smelting industries and other lead using industries and non-lead workers selected from electronic refrigerator manufacturing industry. Blood lead, DMSA chelatable lead and bone lead were chosen for parameters of lead exposure. Plasma and urinary ALA were selected for the effect parameter of lead intoxication. Information for age, smoking, drinking habit and body mass index were also obtained. Job duration for lead workers was also collected. The overall prevalence of the variant allele, ALAD type 1-2 or 2-2(ALAD2) in lead exposed workers was 10.0% (42 out of 419 lead workers) which was not differed from control workers (9.4% : 8 out of 85). The means blood lead and DMSA chelatable lead of lead workers with ALAD 1(ALAD type 1-1) were lower than those of lead workers with ALAD2, but the differences were not statistically significant. On the other hand, the mean of tibia lead of lead workers with ALADI was higher than that of lead workers with ALAD2, but the difference was not statistically significant. DMSA chelatable lead showed highest correlation with log transformed plasma ALA(LALAP)(r=0.682) and blood lead and tibia lead had r=0.650, r=0,402 correlation coefficient with LALAP respectively On the other hand. log transformed urinary ALA(LALAU) had lower correlation coefficient with all three parameters of lead exposure than LALAP. The equation of robustic simple linear regression of blood lead on LALAP was LALAP=2.0439+0.0165PbB in ALADI lead workers and LALAP=2.031+0.0121PbB in ALAD2 lead workers. ALAD genotype in the multiple regression analysis of blood lead with LALAP after adjusting for possible confounders(sex, ago, BMI, smoking and drinking status and job duration) showed significant main effect on LALAP resulting lower LALAP in ALAD2 lead workers than ALADI lead workers. On the other hand, effect modification of ALAD genotype was observed in the multiple regression analysis of tibia lead with LALAP after adjusting for possible confounders, but there was no significant effect of ALAD genotype in the multiple regression analysis of DMSA chelatable lead with LALAP after covariate adjustment. With above results, plasma ALA was found to be a useful effect parameter of lead exposure compared with urinary ALA. It was also observed that ALAD polymorphism made significant effect on the association of blood and tibia lead with ALAP. Thc lower plasma ALA in ALAD2 lead workers suggested supportive effect of ALAD2 in lead exposure.

A Comparison of Lyophilized Amniotic Membrane with Cryopreserved Amniotic Membrane for the Reconstruction of Rabbit Corneal Epithelium

Ahn Jae-Il,Jang In-Keun,Lee Doo-Hoon,Seo Young-Kwon,Yoon Hee-Hoon,Shin Youn-Ho,Kim Jae-Chan,Song Kye-Yong,Lee Hee-Gu,Yang Eun-Kyung,Kim Ki-Ho,Park Jung-Keung The Korean Society for Biotechnology and Bioengine 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

Many researchers have employed cryopreserved amniotic membrane (CAM) in the treatment of a severely damaged cornea, using corneal epithelial cells cultured on an amniotic membrane (AM). In this study, two Teflon rings were made for culturing the cells on the LAM and CAM, and were then used to support the AM, which is referred to in this paper as an Ahn's AM supporter. The primary corneal epithelial cells were obtained from the limbus, using an ex-plantation method. The corneal epithelium could be reconstructed by culturing the third­passage corneal epithelial cells on the AM. A lyophilized amniotic membrane (LAM) has a higher rate of graft take, a longer shelf life, is easier to store, and safer, due to gamma irradiation, than a (AM. The corneal epithelium reconstructed on the LAM and (AM, supported by the two­Teflon rings, was similar to normal corneal epithelium. However, the advantages of the LAM over that of the (AM make the former more useful. The reconstruction model of the corneal epithelium, using AM, is considered as a good in vitro model for transplantation of cornel epithelium into patients with a severely damaged cornea.

크론병에 대한 CoPPLX의 방어효과에 대한 연구

이호학,김유림,문창기,이재일,양병윤,김종수,이정민,정재혁,안석진,박상준,김윤권,김소연,김영중,조민구,최영자,장성조 圓光大學校 醫科學硏究所 2005 圓光醫科學 Vol.20 No.1

김치유래 젖산균의 균체지방산 분석을 이용한 분류학적 연구

이정숙,정민철,김우식,이근철,김홍중,박찬선,이헌주,주윤정,이근종,안종석,박완,박용하,민태익 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.2

표준균주를 포함한 230여개의 김치유래 젖산균에 대한 균체지방산(FAMEs)을 분석하였다. FAMEs profiles는 Euclidian Distance 17.5에 의해 7개의 Major Cluster와 1개의 Single Cluster로 나뉘어졌다. 이중 A, B, C 및 Cluster는 Leuconostoc속으로 분석되어졌고, F는 Lactobacillus속으로 분석되어졌다. 그리고 E와 G cluster는 두개의 Genus가 혼재되어 나타났으며 보충적인 연구가 필요하다. 앞으로 김치유래 젖산균의 균체지방산 분석결과를 기반으로 한 데이타베이스에 95가지 탄소원을 이용하는 수치분류학적 접근방법 및 Pyrolysis Mass Spectrometry 등의 화학적 분석 방법과 분자친화적 연구를 통한 종합적 분류정보 체계가 갖추어지면 젖산균의 신속, 정확한 동정 및 연구에 활발히 이용되어질 것이다. Two hundreds and thirty lactic acid bacteria, mostly isolated from Kimchi, including type strains were sued for analysis of cellular fatty acids. The 230 test strains were recoverd in 7 major and 1 single clusters defined a Euclidian distance of 17.5. These aggregate taxa were equivalent to the genus Leuconostoc (aggregate group A, B, C and D), and the genera Leuconostoc and Lactobacillus (aggregate group G). It is concluded as evident that FAMEs (Fatty Acid Methyl Esters) profile of cell can be used as a criterion in classification of lactic acid bacterial from kimchi. Additional comparative taxonomic studies need to be carried out on well chosen representative strains to determine the most appropriate methods of value.

Alginate 배양내에서 Transglutaminase가 연골막세포에 미치는 영향

박정선,공차배,김충현,안현정,정미현,성상철,김희중,조현철,이상훈,이명철 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2