상아질 접착에서 collagenase와 esterase가 미세인장결합강도에 미치는 영향

정영정,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.2

상아질-레진 접착강도에 대한 collagenase와 esterase의 영향을 살펴보기 위해, 소구치의 교합면 상아질에 Single Bond 2와 Clearfil SE Bond로 접착을 시행하고 미세 시편을 제작하여 PBS, collagenase 용액, esterase 용액에 4주간 보관한 후 미세인장결합강도를 측정, 비교하여 다음과 같은 결론을 얻었다. 1. 모든 보관 용액에서 Single Bond 2의 미세인장결합강도는 Clearfil SE Bond보다 유의하게 낮았다(p<0.05). 2. Single Bond 2의 미세인장결합강도는 collagenase군이 PBS군, esterase군보다 낮았다(p>0.05). 3. Clearfil SE Bond의 미세인장결합강도는 esterase군이 PBS군에 비해 낮았으나(p>0.05), collagenase군보다는 높았다(p>0.05). Collagenase군은 PBS군에 비해 유의하게 낮은 미세인장결합강도를 보였다(p<0.05). The purpose of this study was to evaluate the effect of collagenase and esterase on the microtensile bond strength (μTBS) in dentin bonding. After resin composites were bonded to occlusal dentin, μTBS specimens were formed and stored in PBS, collagenase, or esterase solution. After 4-week storage, μTBS was determined and, the results were as follows: 1. μTBS values of Single Bond 2 were lower than those of Clearfil SE Bond for all storage medium (p<0.05). 2. In single Bond 2 group, collagenase solution lowered bond strength more than PBS and esterase solution (p>0.05). 3. In Clearfil SE Bond group, esterase solution lowered bond strength more than PBS(p>0.05). Collagenase solution lowered bond strength more than esterase solution(p>0.05) and PBS(p<0.05).

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.

당 첨가량에 따른 송이정과의 물성 및 관능 특성

박미란 ( Mi Lan Park ),최수근 ( Soo Keun Choi ),정인창 ( In Chang Jung ),변광인 ( Gwang In Byun ) 한국식생활문화학회 2006 韓國食生活文化學會誌 Vol.21 No.6

CFT구조용 초고강도 충전 콘크리트의 현장 적용을 위한 실험적 연구

이장환,남정민,정근호,김진호,정상진,최문식 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

Due to social problems such as the increasing of land price and the expanding of city, buildings require more complex and bigger components and structure. However, the complex and massive building projects need new technology to solve effect of local buckling and the needs for more space. Hence, Concrete Filled Tube Steel (CFT), the tube steel to hold concrete during pouring and curing of concrete procedure, which helps to reduce local buckling and space, was developed. Most researches on CFT might not be focused on the characteristic of concrete filled in tube but structural analysis. However, it is the essential factor to increase the strength of concrete on CFT for having efficient results. Therefore, this paper will describe how to apply CFT into the construction site through examining High Strength Concrete (800kg/cm2), the strength of core, and bleeding during pouring strategy.

중독한 추체로 증상을 보인 cyclosporine에 의한 뇌증 1예

강정현,곽승근,신현영,김성은,이정호,이정찬,곽상혁,윤환중,조덕연,김삼용,김제,송창준 충남대학교 의과대학 지역사회의학연구소 2000 충남의대잡지 Vol.27 No.1

The use of cyclosporine(CsA), a potent immunosuppressive agent, is associated with numerous side effects. Neurotoxicity was earlier less well known, but with growing experience central nervous system side effects are now reported up to 40% of patients. Among various CsA-induced neurotoxicities, tremor is most common and posterior leukoencephalopathy is well characterized. An encephalopathy presenting with pyramidal weakness, however, seems to be rare and poorly documented. We report here a case of encephalopathy presenting with multiple generalized seizures followed by fluctuating quadriparesis developed a few days after starting CsA and resolved spontaneously after withdrawal of the drug . A 48-year-old woman with aplastic anemia was placed upon immmunosuppressive treatment consisting of antithymocyte globulin(ATG), CsA, and methylprednisolone. Two days after starting the therapy, she developed a generalized seizure. The next day she developed 2 more episodes of seizure and the therapy was stopped. Computed tomogram of the brain was normal. Six days after starting therapy, she developed mild motor weakness and paresthesia of both lower extremities, which progressed to a definite quariparesis confining her to a bed in 3 days. Magnetic resonance imaging(MRI) of the brain revealed asymmetric, bilateral high-signal abnormalites in the subcortical white matter of fronto-temporal areas. After reaching to a maximum with some fluactuation(14 days after starting the therapy) the motor weakness started to be resolved. She was discharged with a almost complete resolution of the weakness 45 days after starting the therapy. Five months later she did well and brain MRI was negative.

유용성 도료와 수용성 도료의 유해성 비교에 관한 연구 : 자동차 보수용 도료를 중심으로

권은혜,김광식,오정룡,최정근,정윤석,이유진,김은아,송세욱,정호근 한국산업위생학회 2001 한국산업보건학회지 Vol.11 No.1

The purpose of this study is to substitute water-based painting materials for the current solvent-based ones used in motor-repairing process to minimize the exposure of organic solvents to the painters. This study assessed the exposure of organic solvents to the painters using water-based and solvent-based painting materials and compared compositions, painting processes and the health hazards of the application of these alternative painting materials. The results of this study are as follows. 1. solvent-based painting materials used in motor-repairing process consist of various organic solvents, which consist primarily of toluene, xylene, ethyl benzene, ethyl methyl bezene, trimethyl bezene, ethyl acetate, butyl acetate, methyl isobutyl ketone, 2-ethoxy ethanol, 2-ethoxy ethyl acetate and toluene-2.4-diisocianate and the others. These organic solvents are know as health-hazardous substances. But water-based painting materials are high-solid, low-solvent ones and consist of such two organic solvents as 2-butoxy ethanol and 2-heptanone and the others. 2. The painters using solvent-based painting materials in motor-repairing process are exposed to various organic acetate, methyl isobutyl ketone, trimethyl benzene, 2-ethoxy ethanol, and 2-ethoxy ethyl acetate. But the painters using solvent-based ones are only exposed to 2-butoxy ethanol and 2-heptanone. 3. By using water-based painting materials in stead of solvent-based painting materials containing health-hazardous organic solvents, the exposure of such organic solvents in the painter's breathing zone can be largely prevented. 4. This study recommends water-based painting materials as substitutes for the current solvent-based ones used in motor-repairing process to minimize the exposure of organic solvents to the painters.

우리나라 일부 석면사업장의 석면폐 유병률

백도명,백남원,최정근,손미아,임정기,이원진,문영한,박정선,최병순 大韓産業醫學會 1995 대한직업환경의학회지 Vol.7 No.1

Asbestos industry has been in operation over 60 years in Korea. However, the prevalence of asbestosis has not been yet reported. With rapid turn-over of workers, previous cross-sectional studies of current workers on the job could not find cases with exposures long enough for the development of asbestosis. This study was done to evaluate asbestosis prevalence of those worksites with operation history of more than 20 years. In total, 139 workers from 5 worksites were examined. Asbestos industries covered in the study include 2 asbestos textile, 1 brake lining, and 2 ship repairing worksites. Chest x-ray was taken from all workers and read by two experts familiar with pneumoconiosis classification according to 1980 ILO guidelines. Those with findings compatible with asbestosis were further ckecked with high resolution computerized tomography (HRCT). Pulmonary function tests were done according to ATS guidelines, and occupational and previous medical history was taken through a standardized interview. Air-borne asbestos was measured according to NIOSH method 7400. The air-borne asbestos concentrations ranged from 0.2-1.3 f/cc for asbestos textile, from 0.7-1.0 f/cc for brake lining, and from 6.3-7.8 f/cc during asbestos removal at ship repairing worksite. Of the 139 workers 25 had abnormal chest radiographic findings, and 10 of them had findings compatible with pneumoconiosis. When work history and current asbestos measurements were accounted, 9 workers who had more than 10 years of asbestos exposure history showed chest radiographic findings of pneumoconiosis with Finally, 4 workers showed finding of pulmonary fibrosis and/or pleural thickening at HRCT, and 2 of them had restrictive lung function changes. The study results showed that, among 139 subjects, there were 4(3%) definite asbestosis cases confirmed with HRCT. The prevalence of probable asbestosis was 7% for 10-14 years of exposure, 13% for 15-19 years of exposure, and 23% for 20 or more years of exposure. The prevalence of compensable asbestosis with abnormal lung function was 4-6% for those with 15 or more years of exposure.

8년간(1992~1999) 산업안전보건연구원에 의뢰된 직업병 심의 사례 분석

강성규,김규상,김양호,최정근,안연순,진영우,최병순,양정선,김은아,채창호,최용휴,김대성,박정선,정호근 대한산업의학회 2000 대한직업환경의학회지 Vol.12 No.2

Objectives : Pneumoconisis and noise-induced hearing loss (NIHL) have been reported as main occupational diseases by the Special Health Examination. The Industrial Accident Compensation Insurance has reported various work-related diseases, however, these two diseases occupied almost a half of compensated cases. Therefore, it was not well known about the status of occupational diseases other than pneumoconiosis, NIHL, and cardio-cerebrovascular accident (CVA). This study was conducted to analyze claimed cases as an occupational disease, that was requested to the Korea Industrial Safety and Health Agency (KOSHA). Methods : The local office of the Korea Labor Welfare Corporation (KLWC) has asked the KOSHA for confirmation of claimed cases as an occupational disease. We analyzed 379 cases requested from KLWC, the Ministry of Labor, employers, unions and occupational health agencies from 1992 to 1999. Results : Male was 80.7 % of the requested cases. Their mean age was 42 years old and 75.5 % of them were more than 35 years old. The requested cases were increased rapidly from 25 cases in 1992 to 108 cases in 1999 and the accept rate was 50.7 %. The majority of requested cases were respiratory diseases(22.4%), cancers(18.5%), Neuropsychiatric problems(14.5%), and musculoskeletal problems(13.5%). The accept rate was high in reproductive, respiratory, musculoskeletal and digestive disorders and low in neuropsychiatric, renal and otologic problems and occupational cancers. 73.6% of them were caused by chemical agents, especially 28.5 % were by organic solvents. 67% of them were clinically confirmed at university hospitals. A half of the cases were from KyongIn area, even the request came from the whole country. Conclusions : A claim was common in workers whose age was over 35 years old and exposure history was over 10 years. The respiratory diseases and neuropsychiatric disorders were still main problems in occupational health and occupational cancers was increasing even though its accept rate was not high yet.

위암 환자의 복강내 투여를 위한 Activated Charcoal-Alginate Bead 제형으로부터 Mitomycin C의 용출 거동

이진호,최선웅,서중기,김동민,정경수,오정연,김진향,노승무,민병무,김용백,김창식,박근성,강대영,송규상,양준묵,조준식,정현용,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Locoregional recurrence is the most common type of recurrence in surgical operation of gastric adenocarcinoma, and peritoneal dissemination is one of the most difficult problems in advanced gastric adenocarcinoma treatment. Because the peritoneal cavity is the most common site of the first recurrence after gastric cancer resection, intraperitoneal chemotherapy seems a logical choice for cancer chemotherapy. In this study, Mitomycin C (MMC)-activated charcoal (CH)-alginate (ALG) beads were prepared by the mixtures of CH particles adsorbed with MMC as an anti-cancer drug and aqueous alginate solution. The alginate is recognized as biodegradable, nontoxic, and biocompatible. The release of MMC from the beads in 0.1 M Tris buffer was stable and continuous until about 1 week. The MMC-CH-ALG beads can be applied in the peritoneal cavity for intraperitoneal chemotherapy since they provide a good adhesiveness on the tissue and controlled release pattern of the drugs.

방역작업자의 브롬화메틸(methyl bromide) 노출수준과 생물학적 모니터링

이종성,이용학,신재훈,최정근,오차재,정호근 한국산업위생학회 2001 한국산업보건학회지 Vol.11 No.3

This study was performed to estimate environmental and biological monitoring of worker exposed to methyl bromide through quarantine fumigation. Airborne methyl bromide and it's metabolites were analyzed by gas chromatography and ion chromatography, respectively. The results are as followings; airborne concentration of methyl bromide(TWA) was 2.08±1.56 ppm(N=8). Dispersion and setting/degas groups were 0.67±0.12 ppm(N=2) and 2.54±1.53ppm(N=6), respectively. Bromide ion concentration in serum was 23.40±14.91㎎/ℓ(N=10) in the exposed workers and 4.74±0.82㎎/ℓ(N=21) in the non-exposed workers. Bromide ion concentration in urine was 35.56±26.89㎎/ℓ(N=11) in exposed group and 6.62±2.31㎎/ℓ(N=21) in non-exposed group. Good correlation was observed between concentration of serum and urine(r^2=0.890 p<0.01). No significant correlations of other determinanats were observed. Calcuated from a regressive curve. the biological half lifes of serum and urine were 10.7 and 5.9 days. In these results, biological monitoring of bromide ion of serum and urine provided useful information for evaluating exposure of workers to methyl bromide, so that an availability of bromide ion of biological samples was showed as biological monitoring indices for methyl bromide.