In vitro Mammalian Chromosomal Aberration Test of Fullerene-C60

Soo Jin Kim(김수진),Kyung Taek Rim(임경택),Hae Won Cho(조해원),Jeong Hee Han(한정희),Hyeon Yeong Kim(김현영),Jeong Sun Yang(양정선) 환경독성보건학회 2009 환경독성보건학회지 Vol.24 No.1

Fullerene의 유전독성을 평가하기 위하여 Chinese hamster유래의 난소유아세포(CHO-K1 cell)를 이용하여 직접법(-S9)과 대사활성화법(+S9 mix)의 염색체이상시험을 실시하였다. 시험물질은 1% CMC 나트륨염의 현탁액(l% CMC 용액)에 희석하여 조제하였다. 대사활성화를 시키지 않은 직접법의 염색체이상시험에서 24시간 투여군은 8단계의 농도(0.078, 0.156, 0.313, 0.625, 1.25, 2.5, 5, 10mM)로 투여하여 실시하였다. 투여 농도 증가에 따른 염색체이상의 빈도가 증가하는 양상이 나타나지 않았다. 48시간의 투여군에서는 8단계의 농도(0.078, 0.156, 0.313, 0.625, 1.25, 2.5, 5, 10mM)로 투여하여 실시하였는데 투여 농도 증가에 따른 염색체이상의 빈도가 증가하는 양상이 나타나지 않았다. 배수체의 염색체이상은 직접법에서 관찰되지 않았다. 대사활성화법을 이용하여 6시간 시험물질을 투여한 시험에 있어서는 8단계의 용량단계 (0.078, 0.156, 0.313, 0.625, 1.25, 2.5, 5, 10mM)를 설정하였는데 투여 농도가 증가함에 따른 염색체이상빈도의 증가양상이 관찰되지 않았다. 이상의 결과를 종합할 때 본 시험물질은 본 시험 조건하에서 CHO-K1세포에서 대사활성화를 시켰을 때 염색체 이상을 유발하지 않는 것으로 판단된다.

쌍태아에서 제 1태아의 분만 후 제 2태아의 지연분만 : 중례보고

김주환,서민정,유희정,노권일,조대현,박정규,이정헌,조성남,손영수 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.3

With the widespread use of fertility medications and techniques of in vitro fertilization, multiple gestation has become epidemic in modern obstetric practice. Delivery of the initial fetus in a multiple gestation usually is followed by delivery of the subsequent fetus or fetuses shortly thereafter. However in rare circumstances, the delivery is delayed for days due to disappearance of uterine contraction after delivery of the first fetus. When uterine activity ceases after the delivery of the first neonate, a policy of nonintervention may be considered in case of an immature or very premature delivery, in order to achieve a gestational age for the remaining fetus(es) more compatible with neonatal survival. We report a case of twin gestation with prolongation of the delivery interval between the twins for 46 days.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

해부학 실습에 의한 의과대학생들의 formaldehyde 폭로 정도와 formaldehyde 과민반응에 대한 조사연구

조수현,김헌,남윤정,김용대 충북대학교 의과대학 충북대학교 의학연구소 1993 忠北醫大學術誌 Vol.3 No.1

Formaldehyde induces not only irritation symptoms of eyes and respiratory tract but hypersensitivity reactions, such as contact dermatitis, allergic rhinitis, and asthma. To estimate the levels of exposure to formaldehyde during cadaver dissection in anatomy laboratory and to investigate the prevalence rates of irritation symptoms, allergic rhinitis and bronchial asthma, air concentrations of formaldehyde within cadaver dissection room were measured, and self-administrative questionnaire and enzyme linked immunosorbent assay(ELISA) were performed upon medical(n=182) and premedical students(n=69). For measurement of air formaldehyde level, chromotropic acid method(NIOSH method 3500) was used. Formaldehyde was conjugated to human serum albumin, and used as antigen in ELISA after identification of conjugation with immunoelectrophoresis. Prevailing symptoms during cadaver dissection were soreness of eyes or throat(92.9%), lacrimation(74.3%), rhinorrhea(49.7%), and sneezing(32.2%). Mean titers of IgE and IgG antibodies specific to formaldehyde-human serum albumin conjugate(F-HSA) of medical students were higher than those of premedical students. However, there was no case whose titers of anti-F-HSA antibody were higher than the twice of those of anti-HSA antibody or higher than the twice of the mean titers of premedical students. These results suggest that medical students were exposed to relatively high concentration of formaldehyde, but few asthma or allergic rhinitis were induced by formaldehyde exposure during cadaver dissection practice.

상아질에 대한 자가 산부식 접착제의 전단결합강도와 SEM 분석 비교

조영곤,노기선,김수미,이영곤,정진호,기영재 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.3

The purpose of this study was to compare shear bond strength and interfacial pattern of composite bonded to dentin using self-etching adhesive systems. Sixty extracted human molars with exposed occlusal dentin were divided into four groups and bonded with four adhesives and composites: Single Bond/Filtek Z 250(SB), Tyrian SPE-One-Step Plus/Aelitefil(TY), Prompt L-Lpop/Filtek Z 250(LP), and one-Up Bond F/Palfique Toughwell(OU). The results of this study were as follows; 1. Shear bond strength for OU was significantly lowet than that of other groups(p<0.05). No significant difference was founded among SB, TY, and LP. 2. Failure modes to dentin showed adhesive and mixed for SB, TY, and LP, but them for OUT showed adhesive in all spceimens. 3. Dentin-resin interface showed close adaptation for SB, TY, and LP, but it showed gap for OU. 4. The hybrid layers for TY, LP, OU were thinner than that of SB. Adhesive layers were observed between composite and hybrid layer, which were 5 ㎛ thick for TY and 10 ㎛ thick for OU.

크세논 램프에 노출된 복합레진의 색조변화

조영곤,서정일,김수미,정진호,이영곤 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.3

The purpose of this study was to evaluate the color changes of the composite resin resulting from xenon lamp exposure in different environments. Composite resin (Z 250 ; shade A1, A2, A3.5 and A4) were applied in a cylindrical metal mold. Seventy five specimens according to environments of exposure were made as follows; Group Ⅰ : aluminum foiling of the specimens in the air at 37℃ for 1 day and 7 days. Group Ⅱ : exposure of xenon lamp to the specimens in the air at 37℃ for 1 day and 7 days. Group Ⅲ : exposure of xenon lamp to the specimens in distilled water at 37℃ for 1 day and 7 days. The color characteristics (L^*, a^*, b^*) of the specimens before and after exposure of xenon lamp were measured by spectrophotometer and the total color differences (ΔE^*) were computed. The results obtained were as follows: 1. In all groups except A1 shade of group Ⅲ, the ΔE^* values presented below 2.0, and group Ⅲ showed the highest ΔE^* values followed by group Ⅱ and group Ⅰ in a decreasing order(p<0.05). 2. In all shades and groups, the more the exposure time of xenon lamp and the lighter the shade were, the higher the tendency for discoloration(p<0.05). 3. The composite resins which was exposed to xenon lamp in the distilled water was more discolored than those in the air (p<0.05). 4. The major changes of composite resins which were exposed to xenon lamp in the air were an increase in yellowness through a positive shift of the b^* value, and those in the distilled water were an increase in darkness and yellowness through a negative shift of the L^* value and a positive shift of the b^* value.

정보통신산업 생산성 변화의 산업간 파급효과 분석

조영상,이정동,박찬수,김태유 한국생산성학회 2002 生産性論集 Vol.16 No.3

The Korean ICT industry is evolving at a dramatic speed, increasing its importance in the overall economy and producing numerous externalities on the other industries. The purpose of this srsearch is to investigate the productivity growth of Korean ICT industry and its effects on the other industries and to derive policy implications. For this purpose we perform inter-industry analysis. Inter-industry analysis is conducted to investigate how close co-relationship exist between ICT industry and other indrstries and to see how much ICT industry affects other industries. Our estimates of the productivity growth in the industry and its contribution to the overall korean Economy suggest the direct contribution of the ICT industry is significant, but its spillovers to the other industries are not so impressive. This implies that the link between ICT industry and other industries is weak and that most of the ICT products are used as final products and not as intermediate goods. We also find the high extent of import penetration in Korean ICT industry to be one of its major problems.

白鼠의 無機質代謝에 미치는 칼슘과 마그네슘의 影響 : 2. Effect on the sodium, potassium, copper and iron metabolism in tissues 2. 組織 중의 Na, K, Cu 및 Fe 代謝에 미치는 影響

曺秀悅,鄭在洪 嶺南大學校 環境問題硏究所 1982 環境硏究 Vol.2 No.1

This experiment was undertaken to investigate the effect of the diet containing two levels of calcium(0.5%, 0.1%) and magnesium (0.04%, 0.0002%) on the sodium, potassium, copper and iron concentrations of kidney, liver and femur in rats. Thirty-two males of Sprague-Dewley strain, 70-80g, were divided into 4 groups and each group(8 rats)was fed ad libitum for 4 weeks. sodium and potassium in the liver, kidney and femur were determined by flame spectrophotometry. Copper and iron in liver, kidney and femur were determined by atomic absorption spetrophotometry. The results obtained are summarized as follow. Net weight gain and feed efficiency ratio were decreased in the calcium and magnesium-deficient groups. The weight of liver, heart and kidney generally showed increasing tendency in the calcium-deficiency group. The weight of iung was showed to decreased in the magnesium-deficient group compared to the control group. The sodium and potassium concentrations of liver, kidney, and femur are the dietary calcium and magnesium levels did not tend to affect on the sodium concentration of kidney and potassium concentration fo femur and liver. But sodium content of liver tended to be significantly increased in the magnesium deficient-group. The potassium concentration of kidney in the deficient-groups(II,III,IV) tended to be greatly increased as compared with the control group. The sodium concentration of femur in the deficient-groups(II, III, IV) was slightly lower as comapared with that of the control group. Both copper and iron contents of the kidney, liver, and femur were the highest in kidney and the dietary Ca and Mg levels were not effected on the copper content of liver. The iron concentration of liver in the Ca-deficient group tended to be greatly higher than that of the other groups. The copper contents of kidney in the Mg-deficient group was lower than that of the other groups, and the iron contents in the deficient groups(II, III, IV) lower as compared with the control group. The copper content of the femur tended to be lower at the deficient levels(II, III, IV) and the copper concentration at the Mg-deficient level was greatly increased as compared with that of the control group.

크릴분말이 콜레스테롤 및 카드뮴 식이 흰쥐의 간 및 심장 지질에 미치는 영향

조영숙,박석규,박정로,손미예,문주석,곽수동 순천대학교 기초과학연구소 1992 基礎科學硏究誌 Vol.3 No.-

In order to investigate effects of krill on lipid components of liver and heart in cholesterol and cadmium-fed rats, male Sprague-Dawley rats were raised for 4 weeks with 8 experimental diets. Krill used in this experiment contained 65.4%(w/w) of protein and 16.7% of lipid. Krill contained 35% of polyunsaturated fatty acids and more unsaturated fatty acids than saturated fatty acids by 2 times. Amino acid content of krill was high in order of Glu, Asp, Tyr and Lys. Rats fed krill diet showed more food intake and weight gain compared with control group. However, food efficiency ratio and weight of liver and heart were not significantly different. The ingestion of cadmium resulted in a severe restriction in growth rate with normal or mild reduction of liver and heart weight. Cadmium also caused a significant decrease in food efficiency ratio. The contents of total and free cholesterol of liver and heart in rats fed krill diets were similar or slightly higher than those fed control diet. Dietary krill also showed no significant difference in liver and heart cholesterol levels in rats with cadmium ingestion. The contents of phospholipid and triglyceride in liver and heart of krill group were slightly higher than those of control group. Supplement of krill reduced triglyceride content of liver in rats ingested with cadmium without any effect on the level of phospholipid and heart lipids. The concentration of cadmium in plasma significantly increased with dietary krill. However, the krill supplement did not influence the concentration of cadmium in liver or heart. A significant accumulation of lipid in liver tissue was observed in all dietary groups but standard group. However, no difference in degree of lipid accumulation was found among the dietary groups. Necrosis and hemolysis of liver in all dietary groups were not shown.

SOL-GEL법을 이용한 강유전체 BaTiO₃박막 및 Ceramics 제조

조채룡,이수재,장민수,김호종,정세영,노동택,김성철 동의대학교 기초과학연구소 1993 基礎科學硏究論文集 Vol.3 No.1

Concentrated solution was prepared for a sol-gel process of BaTiO₃. Barium hydroxide and Ti-isopropoxide were used as the raw materials with methanol and isopropanol as solvents. Dense ferroelectric polycrystalline BaTiO₃thin films with the perovskite structure were fabricated by spin coating of the prepared concentrated solution on a few substrates. From XRD investigation, it was confirmed that tetragonal phase of polycrystalline BaTiO₃powders are formed after heat treatment above 550℃ in air and grain-oriented BaTiO₃thin films are obtained by coating of 0.06M concentrated solution on the substrates. It was observed that surfaces of thin films deposited on the substrates by our methods were formed crack-free and uniformly. The thickness of thin film which depends the concentration of the solution was 400∼900Å for 1 time coating, which was confirmed by SEM analysis. Ceramics and thin films show dielectric constant of 4600 (at 1㎑) and capacitance 300∼800㎊ (at 1㎑) at room temperature, respectively.