• Environmental Mutagens and Carcinogens
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• v.22 no.1
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• pp.1-11
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• 2002

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.195-200
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• 2014

The chances of accidental exposure are augmented as the application of ionizing radiation increases in various fields. Such accidental exposures may occur at nuclear power plants, laboratories, and hospitals. Cytogenetic assays have been used for estimating radiation dose in the situation of the accidents. The micronucleus assay has several advantages over the other cytogenetic methods as it is simple and fast. The present study aimed at investigation of the micronuclei frequencies in cytokinesis-block cells in human blood lymphocytes after ${\gamma}$-irradiation and at establishment of a standard dose response relationship. The samples of peripheral blood were obtained from 6 different donors aged between 24 and 30 years old. The bloods were irradiated in vitro with 0-5 Gy. A linear quadratic dose-response equation was obtained by scoring the micronuclei in binucleated cells; $y=27.87x^2+46.13x+2.08$ ($r^2=0.99$). Irradiation caused a significant decrease in the nuclear division index. Necrotic and apoptotic cells increased in number after irradiation in a dose-dependent manner. In conclusion, the conventional cytokinesis-block micronucleus assay has proven to be the great technique in biological dosimetry. Dose-response calibration curve derived from CMBN assay could be used to estimate the exposure dose during a radiological emergency.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.176-176
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• 2002

In order to investigate whether the induction of micronucleus and aneuploidy in human lymphocytes by Hydroquinone (HQ) is associated with genetic polymorphisms of CYP1A1, GSTM1, GSTT1, NQO1 gene, the cytokinesis-block micronucleus (CBMN) assay in combination with fluorescence in situ hybridization (FISH) technique using specific centromeric probes for chromosome 7 and 8 and PCR-RFLP based genotyping for 30 healthy people were performed.(omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.111-111
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• 2001

The cytokinesis-block micronucleus assay have been emerged as one of the preferred method for assessing chromosome damage. Micronucleus are small, extranuclear bodies that are formed in mitosis from acentric chromosomal fragments or chromosome that are not included in each daughter nuclei.(omitted)

• Journal of Society of Preventive Korean Medicine
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• v.12 no.2
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• pp.51-59
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• 2008

Objectives : Buplueri Radix (BR), used medical plant in Korea traditional medicine, contains various compounds, including a series of triterpene saponins known as saikosaponins. We performed this study for the protective effect of BR against oxidative damage induced by 1,2,4-benzentriol(BT) in human lymphocytes. Methods : In order to investigate the protective effect of BR against carcinogens, genotoxicity induced by benzene metabolite, BT were performed using cytokinesis-block micronucleus(CBMN) assay and comet assay. Results : The frequency of micronucleus at 25, 50 and $100{\mu}M$ concentration of BT were $8{\pm}2.36$, $23{\pm}2.31$, $35{\pm}4.17$ respectively. In addition of BR with concentration of 25 and $50{\mu}g/mL$, MN frequencies were significantly decreased. According to comet assay, BT induced DNA damage in a dose-dependent manner at concentration of 10 and 50 while BT with BR treatment decreased DNA breakage. No genotoxicity was observed by BR($25{\sim}50{\mu}g/mL$) treatment alone on DNA breakage. Since BT can induce DNA damage through the generation of reactive oxygen species(ROS), we examined the level of ROS in human lymphocytes treated with BT and/or BR using DCF-DA, ROS-sensitive probe. The generation of ROS in BT-treated cells was also observed, and BR addition inhibited the level of BT-induced DNA damage. Conclusions : From above results it is suggested that BR could protect the cell and DNA from pro-oxidant effect by ROS by BT

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6955-6960
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• 2014

Background: The cytokinesis-block micronucleus (CBMN) assay is a standard cytogenetic tool employed to evaluate chromosomal damage subsequent to pesticide exposure. Objectives: To evaluate the pooled levels of total micronuclei (MN) and binucleated cells with micronuclei (MNC) in 1000 binucleated lymphocytes among population occupationally exposed to pesticides and further determine the more sensitive biomarker of CBMN. Materials and Methods: A meta-analysis on the pooled levels of MN and MNC in binucleated lymphocytes among occupationally pesticide-exposed populations was conducted using STATA 10.0 software and Review Manager 5.0.24 in this study. Results: We found significant differences in frequencies of MN and MNC in 1000 binucleated lymphocytes between pesticide-exposed groups and controls, and the summary estimates of weighted mean difference were 6.82 [95% confidence interval (95% CI): 4.86-8.78] and 5.08 (95% CI: 2.93-7.23), respectively. However, when we conducted sensitivity analyses further, only the MN remained statistically different, but not the MNC, the summary estimates of weight mean difference were 2.86 (95% CI: 2.51-3.21) and 0.50 (95% CI: -0.16-1.17), respectively. We also observed pesticide-exposed subjects had significantly higher MN frequencies than controls among smokers and nonsmokers, male and female populations, and American, Asian and European countries in stratified analyses. Conclusions: The frequency of MN in peripheral blood lymphocytes might be a more sensitive indicator of early genetic effects than MNC using the CBMN assay for occupationally pesticide-exposed populations.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.243-249
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• 2004

The cytokinesis-block micronucleus (CBMN) assay in combination with FISH technique using chromosome-specific centromeric probes for chromosome 1 and 4 was performed in mitogen stimulated human lymphocytes which were exposed to x-radiation to identify different sensitivity of chromosomes to the induction of micronuclei(MN) and aneuploidy by radiation. The frequencies of micronucleated cytokinesis-blocked(MNCB) cells and MN in binucleated lymphocytes(BN) increased with the increase in radiation dose. A significant induction of aneuploidy of chromosome 1 and 4 were found. The frequency of aneuploidy of chromosome 1 and 4 in the control were 9 per 2,000 BN cells and this increased to 47 and 71 following irradiation at a dose of 1 and 2 Gy, respectively. The induction of aneuploidy of chromosome 1 was higher than that of chromosome 4. The frequency of aneuploid BN cells with MN exhibiting positive centromere signal for either chromosome 1 and/or 4 increased in a dose dependent manner, and that for chromosome 1 is higher than that for chromosome 4. Among the total induced MN in irradiated lymphocytes, smaller proportion of MN exhibit centromeric signal of chromosome indicating that radiation-induced MN are mainly originated from chromosomal breakage rather than chromosomal non-disjunction. These results suggest that x-radiation can induce aneuploidy and supports the finding that chromosome vary in their sensitivity to aneuploidy induction by x-irradiation.

• The Korea Journal of Herbology
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• v.26 no.2
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• pp.31-37
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• 2011

Objectives : This study was focused to investigate the toxicity of Saussurea lappa (SL) extracts in HL-60 cells and human lymphocytes. We also examined the differentiation effect of SL against leukemia cells. Methods : For examining the toxicity of SL, cytokinesis-block micronucleus (CBMN) assay and single cell gel eletrophoresis (SCGE) assay were used in present study. The cell differentiation effect of SL was evaluated by nitroblue tetrazolium (NBT) reduction assay. Results : The inhibition of cell growth in HL-60 cells was observed in a dose-dependant manner after SL treatment for 24 h. According to SCGE assay, HL-60 cells treated with SL increased DNA damage at $10{\mu}g/m{\ell}$, while DNA damage was induced by 0.1, 1, $10{\mu}g/m{\ell}$ concentration of SL in human lymphocytes. Our results indicated that SL have no genotoxic effect in HL-60 cells and human lymphocytes. Additionally, the differentiation effect was induced in $1{\mu}g/m{\ell}$ SL-treated HL-60 cells. Conclusions : From above results it is suggested that SL could be beneficial for the preparation of the useful agent for treating leukemia.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.487-492
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• 1993

정상인 말초혈액임파구 및 C57BL/6마우스 비장임파구에 $^{60}Co{\gamma}-rays$를 in vitro상태에서 조사한 후 500개 또는 1000개의 cytokinesis-blocked(CB) lymphocytes의 미세핵(micronuclei)의 발생빈도를 측정하였다. 방사선조사량에 따라 미세핵의 발생빈도는 증가하였으며 linear-quadratic model로 측정한 결과 선량반응곡선의 식은 인체의 경우 $Y=(0.31{\pm}0.049)D+(0.0022{\pm}0.0002)D^2+13.19$($r^2=1.000$)이었으며, 마우스의 경우 $Y=(1.31{\pm}0.264)D+(0.0015{\pm}0.0006)+8.7$($r^2=0.988$)이었다(Y는 1000개의 CB cell 당 미세핵발생빈도, D는 cGy로 표시되는 조사선량). 인체 말초혈액임파구에 대한 마우스 비장임파구의 상대적 생물학적 효과(relative biological effectiveness)는 미세핵의 발생율이 세포당 0.05~0.8의 범위에서 $1.84{\pm}0.48$이었다. 미세핵분석법은 인체 및 동물의 방사선 피폭시 간편하고 빠른 생물학적 선량측정법으로 사용될 수 있을 것이다.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1119-1123
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• 2014

Head and neck cancers (HNC) are extremely complex disease types and it is likely that chromosomal instability is involved in the genetic mechanisms of its genesis. However, there is little information regarding the background levels of chromosome instability in these patients. In this pilot study, we examined spontaneous chromosome instability in short-term lymphocyte cultures (72 hours) from 72 study subjects - 36 newly diagnosed HNC squamous cell carcinoma patients and 36 healthy ethnic controls. We estimated chromosome instability (CIN) using chromosomal aberration (CA) analysis and nuclear level anomalies using the Cytokinesis Block Micronucleus Cytome Assay (CBMN Cyt Assay). The proliferation rates in cultures of peripheral blood lymphocytes (PBL) were assessed by calculating the Cytokinesis Block Proliferation Index (CBPI). Our results showed a significantly higher mean level of spontaneous chromosome type aberrations (CSAs), chromatid type aberration (CTAs) dicentric chromosomes (DIC) and chromosome aneuploidy (CANE UP) in patients (CSAs, $0.0294{\pm}0.0038$; CTAs, $0.0925{\pm}0.0060$; DICs, $0.0213{\pm}0.0003$; and CANE UPs, $0.0308{\pm}0.0035$) compared to controls (CSAs, $0.0005{\pm}0.0003$; CTAs, $0.0058{\pm}0.0015$; DICs, $0.0005{\pm}0.0003$; and CANEUPs, $0.0052{\pm}0.0013$) where p<0.001l. Similarly, spontaneous nuclear anomalies showed significantly higher mean level of micronuclei (MNi), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) among cases (MNi, $0.01867{\pm}0.00108$; NPBs, $0.0156{\pm}0.00234$; NBUDs, $0.00658{\pm}0.00068$) compared with controls (MNi, $0.00027{\pm}0.00009$; NPBs, $0.00002{\pm}0.00002$; NBUDs, $0.00011{\pm}0.00007$).The evaluation of CBPI supported genomic instability in the peripheral blood lymphocytes showing a significantly lower proliferation rate in HNC patients ($1.525{\pm}0.005552$) compared to healthy subjects ($1.686{\pm}0.009520$) (p<0.0001). In conclusion, our preliminary results showed that visible spontaneous genomic instability and low rate proliferation in the cultured peripheral lymphocytes of solid tumors could be biomarkers to predict malignancy in early stages.