• Journal of Ecology and Environment
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• 제37권1호
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• pp.31-34
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• 2014

The effectiveness of N-acetyl-L-cysteine (NAC) to protect blood cells against Mitomycin C (MMC) induced genotoxicity was investigated in human chronic myeloid leukemia cells (KCL22) using the alkaline comet assay. The comet assay was selected as sensitive and rapid method for analysis of DNA damage and repair in individual cells. NAC treatment alone did not produce any damage in KCL22 cell. But NAC was found to be effective in reducing genotoxic damage in KCL22 cells exposed to MMC. These results confirm the literature data that, given the safety and ability to reduce DNA damage. NAC may be useful to prevent drug-mediated genotoxicity.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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• pp.146-146
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• 2002

The alkaline single cell gel electrophoresis (comet) assay was used to clarify in vitro and in vivo genotoxicity of 2-bromopropane (2-BP). For in vitro studies, fresh medium containing 2-BP (2.50, 1.00, 0.50, 0.25, 0.10, 0.05, 0.01 mM, and vehicle control) were added in human lymphocytes.(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.133-133
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• 2003

In recent years. attention has focused on the application of the alkaline single cell gel electrophoresis (SCGE or Comet) assay in environmental mutagenesis. To evaluate the suitability of the assay as a monitoring. technique, the DNA damages in liver cells and erythrocytes of carp (Cyprinus carpio) exposed to benzo[${\alpha}$]pyrene (B[${\alpha}$]P) were estimated comparatively with the in vivo Comet assay and the micronucleus test (MNT).(omitted)

• International Journal of Internet, Broadcasting and Communication
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• 제11권1호
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• pp.8-16
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• 2019

As smartphone users grow, mobile operators are trying to standardize and commercialize Rich Communication Suite (RCS), which is a next-generation messaging service, so that it can replace legacy messaging services. However, it is not enough to spread RCS widely to the users only by publishing an RCS app. To increase the use of RCS, a web-based open API for common RCS capabilities is needed. By using the API, Internet-based developers can create applications that make use of the RCS capabilities with less effort and time. This paper proposes a lightweight Comet-based open API to allow mobile operators to expose useful information and capabilities to application developers. The system architecture of the open API framework and call flow between relevant nodes are defined. In addition, examples of protocol translations on the framework are provided.

• 한국식품영양과학회지
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• 제32권1호
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• pp.1-7
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• 2003

교역량이 증가되고 있는 수입 오렌지를 대상으로 radiation induced marker검색을 위하여, 방사선 조사시 예상되는 생물학적, 물리적 변화에 기초한 DNA comet assay, 열발광 (TL) 및 전자스핀공명 (ESR) 분석을 실시하였다. DNA comet assay 결과, 오렌지의 씨 및 과육의 cell은 감마선 조사와 무관하게 긴 tail을 가진 comet 모양으로 관찰되었으며, 저온 저장 6주까지도 유사한 경향이 유지되어 marker로의 활용 가능성이 낮았다. TL 측정 에서 비조사 시료는 약 200~30$0^{\circ}C$ 부근에서 매우 낮은 intensity의 glow curve를 나타내었고, 0.5 kGy 이상의 조사 시료에서는 조사 시료 특유의 peak가 18$0^{\circ}C$ 부근에서 나타났으며, 조사 선량의 증가에 따라 intensity 도 점차 증가하였다 TL 측정은 저장 6주까지도 가능하였고, TL ratio(TL$_1$/TL$_2$)의 산출은 검지 결과의 신뢰도를 높여주었다. ESR 측정에서는 시료의 씨, 과육 및 과피 부위에서 방사선 조사 유래의 특이적인 signal이 나타나지 않아 조사 시료와 비조사 시료의 구분이 불가능하였다. 이상의 결과에서 볼때 오렌지는 TL 분석에 의해 방사선 조사 여부의 확인이 가능하며 이 방법은 오렌지의 저온 상품성이 유지되는 저장6주 이후에도 적용이 가능한 것으로 나타났다.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2000년도 추계심포지움 및 학술발표회:바이오모니터링 기법을 이용한 환경위해성 평가
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• pp.53-53
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• 2000

• Journal of Astronomy and Space Sciences
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• 제17권2호
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• pp.147-150
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• 2000

A fluorescent equilibrium model for the 1-0 band of the A-X system of ${18}^{OH}$ has been constructed. Line positions and intensities have been calculated for possible future spectroscopic observations of these bands from space in order to derive ${18}^{O}/{16}^{O}$ ratios in comets. It is demonstrated that the strong lines of the 1-0 band can be observable for a moderately bright comet using a high resolution spectrometer with a reasonable exposure time.

• Environmental Analysis Health and Toxicology
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• 제14권1_2호
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• pp.1-12
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• 1999

Recently, several new methods for the detection of genetic damages in vitro and in vivo based on molecular biological techniques were introduced according to the rapid progress in toxicology combined with cellular and molecular biology. Among these methods, mouse lymphoma thymidine kanase (tk) gene forward mutation assay, single cell gel electrophoresis (comet assay) and transgenic animal and cell line model as a target gene of lac I (Big Blue) and lac Z (Muta Mouse) gene mutation are newly introduced based on molecular toxicological approaches. The mouse lymphoma tk$\^$+/-/ gene assay (MOLY) using L5178Y tk$\^$+/-/ mouse lymphoma cell line is one of the mammalian forward mutation assays, and has many advantages and more sensitive than hprt assay. The target gene of MOLY is a heterozygous tk$\^$+/-/ gene located in 11 chromosome, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. The comet assay is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakages in mammalian cells, Also, transgenic animal and cell line models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease process, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Also in vivo acridine orange supravital staining micronucleus assay by using mouse peripheral reticulocytes was introduced as an alternative of bone marrow micronucleus assay. In this respect, there was an International workshop on genotoxicity procedure (IWGTP) supported by OECD and EMS (Environmental Mutagen Society) at Washington D. C. in March 25-26, 1999. The objective of IWGTP is to harmonize the testing procedures internationally, and to extend to finalization of OECD guideline, and to the agreement of new guidelines under the International Conference of Harmonization (ICH) for these methods mentioned above. Therefore, we introduce and review the principle, detailed procedure, and application of MOLY, comet assay, transgenic mutagenesis assay and supravital staining micronucleus assay.

• Journal of Nutrition and Health
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• 제36권1호
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• pp.24-31
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• 2003

The present study was attempted to investigate the antioxidant capacity of popular yellow-green vegetable juices (kale, Angelica keishei, carrot, small water dropwort) and to investigate the effect of vegetable juices on protecting oxidative damage to DNA in cultured Chinese hamster lung (CHL) cells. Antioxidant capacity was analyzed by TRAP assay (Total radical-trapping antioxidant potential). Cellular DNA dmamage was measured by SCGE (single-cell gel electrophoresis, also known as comet assay. Cells incubated in medium with PBS (negative control) or with various concentration of the freeze dried green juices (25, 50, 100, 250 $\mu\textrm{g}$/$m\ell$) resuspended in PBS were treated with $H_2O_2$ (200 ${\mu}{\textrm}{m}$) as an oxidative stimulus for 5 min at 4$^{\circ}C$. The physiological function of each vegetable juice on oxidative DNA damage was analyzed and expressed as tail moment (tail length X percentage migrated DNA in tail) . Kale juice had the highest TRAP value suggesting that kale has the highest antioxidant capacity followed by Angelica keishei, small water dropwort and carrot. Cells treated with $H_2O_2$ had extensive DNA damage compared with cells treated with PBS or pre-treated with vegetable juice extracts. All green juices inhibited $H_2O_2$-induced DNA damage with kale being the most effective juice among the tested juices. These results indicate that green juice supplementation to CHL cells followed by oxidative stimulus inhibited damage to cellular DNA, supporting a protective effect against oxidative damage induced by reactive oxygen species. (Korean J Nutrition 36(1) : 24-31, 2003)

• Molecular & Cellular Toxicology
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• 제1권3호
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• pp.179-188
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• 2005

To develop the novel anti-allergic drug, many sophoricoside derivatives were synthesized. Among these derivatives, JSH-II-3, VI-3, VII-3, VIII-3, VII-20 and VII-20 (sodium salt) were selected and subjected to high throughput toxicity screening (HTTS) because they revealed strong IL-5 inhibitory activity and limitation of quantity. Single cell gel electrophoresis (Comet) assay, mouse lymphoma thymidine kinase ($tk^{+/-}$) gene assay (MOLY), chromosomal aberration assay in mammalian cells and Ames reverse mutation assay in bacterial system were used as simplified, inexpensive, short-term in vitro screening tests in our laboratory. Through the primary screening using the comet assay, we could choose the first candidates of sophoricoside derivatives with no genotoxic potentials as JSH-VI-3, VII-3, VII-20 and VII-20 (sodium salt). Also JSH-VII-3, VII-20 and VII-20 (sodium salt) are non-mutagenic in MOLY assay, while JSH-II-3 is mutagenic at high concentration with the presence of metabolic activation system in both comet assay and MOLY assay. The selected derivatives (JSH-VI-3, VII-3, VII-20 and VII-20 (sodium salt) are not mutagenic in S. typhimurium TA98 and TA100 strains both in the presence and absence of metabolic activation. From results of chromosomal aberration assay, 6 h treatment of JSH-VI-3, VII-3 and VII-20 (sodium salt) were not revealed clastogenicity both in the presence and absence of S-9 mixture. Therefore, we suggests that JSH-VI-3, VII-3, VII-20 and VII-20 (sodium salt), as the optimal candidates with both no genotoxic potential and IL-5 inhibitory effects must be chosen. To process the development into new anti-inflammatory drug of these derivatives, further investigation will need.