• Journal of Radiation Protection and Research
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• 제24권2호
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• pp.93-99
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• 1999

Alkaline single cell gel electrophoresis (SCGE) assay는 일명 혜성분석이라고 부르며 in vivo 와 in vitro 에서 많은 화학적, 생물학적인 인자에 의한 DNA 손상을 감지하는데 유용한 기법으로 각각의 세포에서 DNA 단일 가닥 절단과 알칼리에 약한 장소를 평가하는 새로운 방법으로 인정되고 있다. 단세포 겔 전기영동법 (SCGE)을 사용하여 복숭아씨 추출물이 방사선에 의하여 사람 림프구 DNA에 나타나는 손상을 보호하는 지 여부를 평가하였다. 복숭아씨 추출물로 10 분간 전처리한 림프구를 0, 0.1, 0.3, 0.5, 1.0, 2.0 Gy 의 방사선으로 조사하였고 방사선만을 조사한 림프구 실험군과 비교평가하였다. 혜성분석에서 DNA 가닥 절단에 대한 표식인 tail moment의 증가는 감마선에 대해서 뚜렷한 선량-반응 관계를 나타내었으며 각각의 농도별로 복숭아씨 추출물이 처리된 림프구의 DNA 손상은 현저히 감소하였다. 단세포 겔 전기영동법을 통한 평가결과 복숭아씨 추출물은 방사선에 의한 림프구 DNA 손상에 대한 탁월한 방어효과를 나타내었다.

• Toxicological Research
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• 제23권1호
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• pp.25-31
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• 2007

To evaluate the protective effect of Houttuynia cordata on hydrogen peroxide-induced oxidative DNA damage in HepG2 cell line, we used an alkaline single-cell gel electrophoresis (SCGE; comet assay). The DNA damage was analyzed by tail moment (TM) and tail length (TL), which used markers of DNA strand breaks in SCGE. The $100{\mu}g/ml$ of methanolic extract of Houttuynia cordata root showed significant protective effects (p < 0.01) against hydrogen peroxide-induced DNA damage in HepG2 cells and increased cell viability against hydrogen peroxide. The results of this study indicate that Houttuynia cordata root methanol extract acts as a potential antioxidant, and exhibits potential anticancer properties, which may provide a clue to find applications in new pharmaceuticals for oxidative stability.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2002년도 학술대회
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• pp.145-153
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• 2002

유해 화학 물질류에 의해 오염된 해양 환경 시료의 환경독성 수준을 평가하기 위하여 다양한 화학물질에 대해 민감성이 우수한 생물학적 독성평가기법을 개발 하고자하였다. 지속성 유기오염 물질 중 다환 방향 족 탄화수소(PAHs)를 처리한 광어(Conger myriaster)와 개조개(Saxidomus pupurata)의 DNA 손상정도를 single cell gel electrophoresis assay(comet assay)를 통해 분석하였다. PAHs 중 광양만에서 높은 농도로 검출되는 benzo(a)pyrene을 농도별(0, 10, 50, 100 ppb)로 처리한 후 2일과 4일에 광어의 혈액세포와 개조개의 근육세포를 채취해 comet assay를 실시하였다. benso(a)pyrene에 대한 DNA 손상정도를 처리된 농도와 생물종에 따라 다르게 나타났는데 광어의 혈액세포는 2일에 가장 DNA 손상정도가 높았고, 4일에는 회복되는 경향을 나타냈다. 개조개의 근육세포는 시간이 지나면서 DNA 손상정도가 증가하는 경향을 보였다. 이와 같은 결과는 comet assay 기법이 유해 화학물질로 오염된 해양생물 종의 환경독성을 검색하는 유용한 수단이 될 수 있음을 보여준다.

• 한국환경과학회지
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• 제14권11호
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• pp.1071-1079
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• 2005

Using single cell gel electrophoresis, DNA single strand breaks were determined in various marine organisms. DNA damage on fish blood cells was detected to know whether there was a difference between Incheon, Pohang, Masan, and Tongyeong as a control site. Tongyeong showed the lowest DNA damage among the study areas. Mussels, transplanted to Masan Bay for one month, revealed high DNA damage at sites with high economical activity. In two weeks exposure of polychaete to Incheon sediments, higher DNA damage was detected in the sediment adjacent to Incheon harbor than open sea. These results suggested that the marine organism from the polluted area revealed a relatively high DNA damage. In addition, these areas might be contaminated with genotoxic compounds and comet assay was useful as a bioassay to detect DNA damage in marine organisms.

• 한국환경성돌연변이발암원학회지
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• 제22권2호
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• pp.83-89
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• 2002

The single cell gel electrophoresis (comet) assay is one of the useful tools for the study of genetic damage in humans exposed to environmental mutagens and carcinogens. This study was undertaken to evaluate the status of DNA damage in peripheral lymphocytes depending on their sex, age, smoking habits, and other factors in normal healthy Korean population. The 99 volunteers included in the study and out of these, 36 volunteers were smoker and 63 volunteers were non-smoker aged between 20-59 years. All individual answered a questionnaire that assessed their general information including smoking habits and the extent of the environmental tobacco smoke (ETS) exposure, and blood samples were obtained. There was a statistically significant difference in the extent of DNA damage between smoker and non-smoker (p<0.001). A significant difference was also observed between male and female (p<0.001) and amongst the different group of age (p<0.005), however, correlation analysis showed that only smoking habit was a significant factor for DNA damage. No significant effect of smoking duration, number of cigarettes smoking a day, SPY (smoke pack years) in smokers and environmental tobacco smoke exposure in non-smokers on the status of DNA damage was observed.

• Journal of Plant Biotechnology
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• 제31권3호
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• pp.225-230
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• 2004

방사선에 노출된 고추유묘의 잎으로부터 세포핵을 분리하여 단세포전기영동방법인 comet 분석을 통하여 핵 DNA의 손상정도를 조사하였다. Comet 분석에서 꼬리부분의 길이 (T)와 머리부분의 길이 (H)를 측정하여 T/H 비율을 조사하였다. 무처리세포는 T/H 비율이 1.28이었으나 50 및 100 Gy의 방사선을 처리한 세포는 각각 3.54 및 3.39로 방사선처리에 의해 상당량의 핵 DNA가 손상을 입은 것으로 나타났다. Comet의 head-DNA량은 무처리가 76.8%였으나 50 및 100 Gy를 처리한 세포는 각각 55.9% 및 59.5%를 보였다. 고선량의 방사선을 처리하기 전에 미리 20 Gy 이하의 저선량 방사선을 종자에 전처리하였을 경우 종자의 발아 및 생장에 대한 영향은 없었지만, 후속 고선량에 대한 핵 DNA의 손상은 경감되는 경향을 보였다.

• Environmental Analysis Health and Toxicology
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• 제21권2호
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• pp.127-138
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• 2006

In urban areas, diesel exhaust particles (DEP) are probably a major component of particulate matters, especially in Korea where drive many diesel vehicles. The aim of this study was to investigate genotoxic effects of DEP using single ceil gel electrophoresis. In order to evaluate the mechanisms of DEP genotoxicity, the rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed. Total diesel particles (DEPT) was collected without site fractionation from diesel engine bus and dichloromethane extract was obtained. The organic extract of DEPT revealed DNA damage itself in NIH/3T3 cells. The level of DNA breaks plus oxidative DNA lesions and microsome mediated DNA damage was assessed by modified single cell gel eletrophoresis. DEPT was able to induce oxidative DNA damage as well as microsome mediated DNA damage. Vitamin C as an model antioxidant reduced DNA damage in endonuclase III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor. reduced DNA damage in the presence of S-9 mixture. $DEP_T$ is the sources of oxidative stress, but antioxidants can significantly reduce oxidative DNA dmage. And $DEP_T$ may contain indirect mutagens which can be inhibited by CYP1A1 inhibitors. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) were evaluated for their in vitro antigenotoxic effects. BV and BF showed potent Inhibitory effects against DEPT induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P4501A1 in cell culture.

• Toxicological Research
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• 제22권2호
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• pp.75-85
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• 2006

This study was designed to evaluate the possible DNA damaging effects of T-2 toxin using an alkaline single cell gel electrophoresis (SCGE) comet assay and also to investigate toxic effects in chickens. A total of 20 chickens were used in these experiments. Graded concentrations of dietary T-2 toxin (0, 4, 8, and $16{\mu}g/g$ of diet) were given to groups of 5 broiler chickens. In comet assay, The DNA damage was analysed by the tail extent moment (TEM) and tail length (TL), which were used as markers of DNA strand breaks in SCGE. A significant dose-dependent increase in the extent of DNA migration as well as in the percentage of cells with tails was observed after treatment with T-2 toxin (P<0.05). Treatment with the low T-2 toxin ($4{\mu}/g$ of diet) induced a relatively low level of DNA damage in comparison with the high T-2 toxin ($16{\mu}/g$ of diet) group. The growth rate was significantly reduced by concentrations of 8, and $16{\mu}/g$ of diet (P < 0.05). The feed conversion ratio were significantly affected by any concentrations (P < 0.05). The relative weight of the spleen, and lung was decreased by the growth inhibitory concentrations. The bursa of Fabricius, thymus, and kid- ney were decreased in relative weight by concentrations of $16{\mu}/g$ of diet. The relative weight of the liver and heart were unaffected. The hemoglobin (Hb), hematocrit (HCT), and mean corpuscular hemoglobin (MCH) were decreased at concentration of $16{\mu}/g$ of diet. As compared with control chickens, there was no marked change in serum components except uric acid in T-2 treated chickens. All lymphoid tissues retained atrophic and lymphoid cell depletion throughout the three weeks trial.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1997년도 제20회 화학물질의 환경독성과 건강영향
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• pp.101-101
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• 1997

Comet assay, single cell gel electrophoresis has been known as useful, rapid, simple, visual, and sensitive technique for measuring the DNA breakage in mammalian ce1ls. For evaluation of DNA damage using comet assay, early studies reported a change in comet length and intensity with DNA damage using simple visual technique, such as fluorescence microscopy with eyespiece. In recent, some workers are observing and analyzing nucleotide of comets using quantitative fluorescence image analysis system to estimate 'tail moment', which is defined as the product of the tail length and the fraction of total DNA in tail. Our laboratory also adopted the image analysis software for qualification. In addition, many of the practical features of comet assay render it potentially attractive as useful tool for molecular toxicology and carcinogenesis, because the system is already showing considerable promise as rapid predictor in both in vitro and in vivo experimental designs. Recently, the comet assay becomes a attractive technique to study of apoptosis, because apoptotic fragmentation of nuclear DNA into nucleosomal sizes can be evaluated by the comet assay. So, we attempted to apply the comet assay to studying the effect of various stress on the apoptosis-sensitive cell lines. Particularly, focusing on the hyperthermic apoptosis, we could find that heat shock(44˚C for 60 minutes) was sufficient to induced apoptosis in these cell lines. But using the highly sensitive comet assay, we could not detect DNA breaks immediately after heat shock.

• 한국식품영양과학회지
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• 제30권6호
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• pp.1076-1081
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• 2001

현재 중국으로부터 수입량이 증가하고 있는 땅콩을 대상으로 국산과 중국산 시료의 TL, ESR, DNA comet(single cell gel electrophoresis) 분석을 실시하여 원산지별 특성을 비교하였다. Density separation 방법으로 추출한 미네랄의 TL측정 결과, 감마선 조사되지 않은 시료는 25$0^{\circ}C$ 부근에서 intensity가 낮은 glow curve를 나타내었고, 조사 시료는 18$0^{\circ}C$ 부근에서 아주 강한 intensity의 glow curve를 보여주었다. 첫 번째 측정된 glow curve(TL$_1$)의 normalization을 위하여 재조사 방법에 의해 TL$_2$를 측정하여 TL ratio(TL$_1$/TL$_2$)를 비교해 본 결과, 비조사 시료는 0.05 이하, 조사 시료는 0.2이상으로 방사선 조사 여부의 판별이 가능하였다. 땅콩껍질을 사용한 ESR 측정에서는 조사 유래의 특이적인 signal이 나타나지 않아 적용 가능성이 낮았다. DNA comet assay 결과, 비조사 시료는 tail이 없거나 아주 짧은 전형적인 intact cell을 나타낸 반면, 조사 시료는 long tail을 가진 comet을 나타내면서 선량 의존적으로 (r=0.761/Korean, r=0.768/Chinese) tail length가 증가하여 조사 여부의 확인이 가능하였다. 모든 실험에서 원산지별 차이는 크지 않았다. 이상의 결과로 볼 때 땅콩의 방사선 조사 여부 확인에는 TL 분석 및 DNA comet assay가 적용 가능하였다.