• 한국연초학회지
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• 제26권2호
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• pp.152-158
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• 2004

Among short-term in vitro genotoxicity assays, micronucleus assays are rapid, inexpensive, and less labor-intensive system. We have undertaken a comparative study of sensitivity of cigarette smoke condensate(CSC) by general micronucleus(MN) assay and cytokinesis-block micronucleus(CBMN) assay. In this study, V79 Chinese hamster cells were employed to evaluate and compare the genotoxicity of CSC of Kentucky Reference Cigarette 2R4F by 2 kinds of in vitro MN assay methods. To determine the optimum concentration of cytochalasin B(CYB) to obtain the maximal number of binucleated cells for CBMN assay, triplicate cultures of growing cells were treated with CYB for 15 h. CYB treatments caused a concentration-dependent increase in cytotoxicity($1\~4{\mu}g/mL$) and proportion($0.25\~1\;{\mu}g/mL$) of binucleated cells. These data suggested that 1 ug/mL of CYB is as an optimum dose for CBMN assay in binucleated V79 cells. Short treatment(4 h) of CSC induced a micronucleated cells with a concentration-dependent response in the presence or absence of CYB, but CSC-induced MNs were weakened when S9 was present. Long treatments(19 h) of CSC also induced a significant increase MN formation with a concentration-dependent response. At a concentration of 75 ${mu}g/mL$, the MN cell frequencies of general MN assay and CBMN assay were $6.5\%\;and\;11.7\%$, respectively. Linear regression analysis revealed a good correlation in CBMN assay between a concentration of CSC and MN cell frequency. All these data indicated that CBMN assay is more sensitive to the induction CSC-induced MN than general MN assay.

• 한국임상수의학회지
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• 제20권3호
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• pp.364-368
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• 2003

Cytogenetic and hematological analysis was performed in peripheral blood from the cattle associated with abnormal delivery around nuclear power plant area. The frequency of micronuclei (MN) in peripheral blood lymphocytes from cattle was used as a biomarker of radiobiological effects resulting from exposure to environmental radiation. An estimated dose of radiation was calculated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 Gy to 4 Gy from the bovine lymphocytes with in vitro irradiation. MN rates in live malformed calf, dams of malformed calves and other cattle living in the same barn from the regions around nuclear power plant, and cattle in control area were 9/1000, 10.8/1000, 13.3/1000 and 10.0/1000, respectively. There were no significant differences in MN frequencies and hematological values between the cattle associated with abnormal delivery around nuclear power plant area and those of control area. This study indicates that the congenital abnormalities near nuclear power plant seemed to be caused by other aetiology.

• Molecular & Cellular Toxicology
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• 제3권3호
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• pp.172-176
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• 2007

Butylated hydroxytoluene (BHT) is widely used antioxidant food additives. It has been extensively studied for potential toxicities. BHT appears adverse effects in liver and thyroid. In this study, we evaluated the genetic toxicity of BHT with more advanced methods, in vitro mouse lymphoma assay $tk^{+/-}$ gene assay (MLA) and in vivo mouse supravital micronucleus (MN) assay. BHT did not appear the significantly results in the absence and presence of metabolic activation system with MLA. Also, in vivo testing of BHT yielded negative results with supravital MN assay. These results suggest that BHT itself was not generally considered genotoxic.

• Molecular & Cellular Toxicology
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• 제3권2호
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• pp.113-118
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• 2007

Chlorobenzenes due to their acute toxicity and the capability of bioaccumulating are of great health and environmental concern. Especially, 1, 2-dichlorobenzene (CAS No. 95-50-1) is used for organic synthesis, dye manufacture, as a solvent and for other applications in chemical industry. Adverse effects of 1, 2-dichlorobenzene includes increases in liver and kidney weights and hepatotoxicity. In this study, we evaluated the genetic toxicity of 1, 2-dichlorobenzene with more advanced methods, in vitro mouse lymphoma assay $tk^{+/-}$ gene assay (MLA) and in vitro mouse supravital micronucleus (MN) assay. 1, 2-Dichlorobenzene appeared the significantly positive results and the induction of large mutant colonies only in the presence of metabolic activation system with MLA. But in vitro testing of 1, 2-dichlorobenzene yielded negative results with supravital MN assay. These results suggest that 1, 2-dichlorobenzene may play a mutagen rather than clastogen in vitro mammalian system.

• 한국환경농학회지
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• 제33권2호
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• pp.138-143
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• 2014

님추출물과 고삼추출물은 식물추출물 유기농업자재로 우리나라에 등록되어 친환경농산물 재배에 널리 사용되고 있다. 본 연구에서는 님추출물 2종과 고삼추출물 2종에 대한 안전성을 확인하고자 Chinese hamster lung cells을 이용한 in vitro 소핵시험(vitMN)을 통해 유전독성을 평가하였다. 시험은 cytochalasin B 적용군과 비적용군으로 구분하여 시험하였으며, 양성대조물질로 mitomycin C와 colchicine을 사용하였다. 시험 결과, 님추출물 시료 2종과 고삼추출물 시료 2종은 처리 농도에 따라 소핵발생 비율이 증가하였으나 모든 시료 처리군에서 전체 발생률이 2.2% 미만으로, 음성대조군 대비 2배 미만의 소핵이 관찰되었다. 따라서 님추출물 및 고삼추출물 시료는 본 시험의 vitMN 결과 최종적으로 음성으로 확인되었다. 또한 본 연구와 동일한 시료를 이용한 선행연구에서 복귀돌연변이 시험에서 음성을 보인 결과를 근거로 battery system에 의거해 종합적으로 평가하였을 때 님추출물과 고삼추출물 시료는 유전독성을 일으키지 않는 것으로 최종 판정하였다.

• 대한수의학회지
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• 제36권2호
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• pp.277-281
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• 1996

A technique to improve the analysis of micronuclei(MN) in lymphocytes as a cytogenetic indicator is reported. For the purpose of diminishing the variation of the result from individual reader and making it easier to distinguish accurately a cytokinesis blicked(CB) lymphocyte and micronuclei, we tried a modified one-step silver staining technique as a method for detection of the argyrophilic nucleolar organizer region(AgNOR) with or without conventional Giemsa stain in the slide from CB method. Compared with the conventional Giemsa stain, the preparation processed with this method are especially useful for the accurate analysis of MN of cultured lymphocyte with cytochalasin B. This method will be a useful technique for automated calculation of MN.

• Toxicological Research
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• 제27권2호
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• pp.119-123
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• 2011

In this research, the genotoxic effect of Picrorrhiza Rhizoma (PR) aqueous extract was evaluated using the mouse micronucleus test. PR extract was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000 and 500 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control. The appearance of a micronucleus (MN) in polychromatic erythrocyte (PCE) is used as an index for genotoxic potential, and PCE ratio is used as an index of cytotoxicity. Although significant (p < 0.01) increase of the number of PCE with one or more nuclei (MNPCE) was detected in cyclophosphamide treated groups, no significant increases of MNPCE numbers were observed in all three different dosages of PR extracts treated mice with over 0.39 of the individual polychromatic erythrocyte ratio in all mice used in this study. The results obtained indicated that PR extract shows no genotoxicity effects up to 2000 mg/kg dosing levels.

• 한국연초학회지
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• 제25권2호
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• pp.128-136
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• 2003

Although tobacco smoke has been known to have genotoxicity as well as cytotoxicity, the sensitivity of the cell lines used against cigarette smoke is poorly understood. The objective of this study was to evaluate and compare the genotoxicity of several cell lines, which are routinely used in the in vitro assays, with cigarette smoke condensate(CSC) of Kentucky Reference Cigarette 1R4F. In the micronucleus(MN) induction assays, murine(CHO-K1, V79, BALB/c 3T3) cell lines and human(MCF-7, A549) ones were used. As a result, the CSC exhibited cytotoxicity with a concentration-dependent response in all cell lines. EC$_{50}$ of CSC in CHO-K1, V79, BALB/c 3T3, MCF-7 and A549 were 140, 125, 100, 116 and 109 $\mu\textrm{g}$/mL, respectively. On the other hand, the spontaneous micronucleated cell(MNC) frequency was stable and reproducible in every cell lines tested in this study. The dose-response of various cell lines to the induction of MN by CSC was estimated using linear regression analysis. CSC(0～100 $\mu\textrm{g}$/mL) caused a dose-dependent MN induction in CHO-K1, V79, BALB/c 3T3 and MCF-7 cell lines. Putting together all the data obtained and linear regression analysis of the data, we concluded that V79 cells are more susceptible to the accurate assessment of CSC-induced MN than the others.s.

• Safety and Health at Work
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• 제6권3호
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• pp.184-191
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• 2015

Chemical mutagenicity is a major hazard that is important to workers' health. Despite the use of large amounts of allyl chloride, the available mutagenicity data for this chemical remains controversial. To clarify the mutagenicity of allyl chloride and because a micronucleus (MN) test had not yet been conducted, we screened for MN induction by using male ICR mice bone marrow cells. The test results indicated that this chemical is not mutagenic under the test conditions. In this paper, the regulatory test battery and several assay combinations used to determine the genotoxic potential of chemicals in the workplace have been described. Further application of these assays may prove useful in future development strategies of hazard evaluations of industrial chemicals. This study also should help to improve the testing of this chemical by commonly used mutagenicity testing methods and investigations on the underlying mechanisms and could be applicable for workers' health.

• 한국식품영양과학회지
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• 제29권5호
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• pp.881-887
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• 2000

The antimutagenic effects of persimmon leaf tea extract (PLTE) at concentration levels consumed by human were examined in mice using micronuleus induction with MMC(mitomycin C) or 4-NQO (4-nitroquinoline-1-oxide). When mice received oral gavage of 10 equivalent to PLTE 24 hr and 6 hr before, and 5 equivalent to PLTE 6 hr before and 3 hr after intraperitoneal injection of MMC, a significant decrease in the frequency of micronuclei were observed. The induction of micronuclei by 4-NQO was suppressed by oral dosage of PLTE at 5 equivalent to PLTE 6 hr before and 3 hr after, 10 equivalent to PLTE 3 hr before and 3 hr after intraperitoneal injection of MMC. Though the components of PLTE have not been analyzed so far, our present results suggest the existence of several bio-antimutagens and/or desmutagens in PLTE, beside catechin, well-known antimutagen.