• 한국환경보건학회지
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• 제24권2호
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• pp.88-99
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• 1998

This study was undertaken to find out the bio-effects due to be a radiation fractionated exposure. The experimental animals were divided into the control group and the radiation exposure groups of 20cGy, 40cGy and 80cGy with 220 male Sprague-Dawley rats at 6 weeks old. The radiation exposure groups were fractionated exposed from each 20cGy, 40cGy and 80cGy for every 5 days. The chromosome aberrations, the frequency of SCE, the changes of body weight, hematological values and enzyme activities were investigated for the fractionating exposure times and the time after fractionated exposure. The results were summarized as follows 1. The body weight of the radiation exposure groups were significantly decreased compared with control group according to the increasing fractionated exposure times, and it was the lowest values at the immediately after the end of the fractionating exposed, but it was recovered with the level of control group at 3rd weeks gradually increased 1st week after fractionated exposure. 2. The values of WBC, RBC, Hb and Hct in the radiation exposure groups were significantly decreased than those the control group, but the values of GOT, GPT, ALP, and LDH in the radiation exposure groups were significantly increased than those of the control group. 3. The frequency of chromosomal aberration were increased according to the increasing fractionated exposure dose, and it showed the highest at 5th days after fractionated exposed. The types of chromosomal aberration were occurred such as a numerical abnormality, deletion, break and duplication, it was not recovered immediately and maintained high frequency than the control group. 4. The frequency of SCE were significantly increased according to the increasing fractionated exposure dose in 20cGy, 40cGy and 80cGy groups. But it was recovered the level of control group at 7th days after fractionated exposure. According to the above results, this study could confirm that the frequency of chromosomal aberration and SCE were increased with fractionated exposure dose, the other hand, the changes of body weight, hematological values and enzyme activity values were significantly affected according to the increasing fractionated exposure dose.

• Journal of Radiation Protection and Research
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• 제19권1호
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• pp.51-68
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• 1994

임파구의 염색체이상 빈도로부터 피폭자의 흡수선량을 구하는 방법은 사고로 인해 급성 피폭을 받는 경우 유용하게 사용될 수 있다. 그러나 방사선 피폭 후 시간이 경과함에 따라 불안정 염색체이상을 가진 임파구는 감소하게 된다. 이에 방사선 치료후 시간 경과에 따른 불안정 염색체이상 빈도의 변화를 규명하고자 한다. 전골반에 50.4Gy의 방사선 치료를 받은 총 20명의 자궁경부암 또는 자궁내막암 환자를 대상으로 41개의 검체를 얻었다. 채혈의 시기는 방사선 치료후 1일 3주, 6주, 9주, 12주, 24주, 52주, 104주, 156주, 208주, 520주로 하였다. 이들 말초혈액의 임파구에 대해 전혈미세배양을 실시한 후 임파구의 불안정 염색체이상을 관찰하여 Ydr, Qdr, Qdra를 얻었다. Ydr 값은 방사선 치료가 끝난 직후부터 3주까지 plateau를 보였고 이후 감소하는 경향이었다. Ydr의 평균값은 치료후 3주에 0.29에서 급격히 감소하여 2년 후 0.05로 감소하였으며 이후 5년까지 서서히 감소하였다. 회귀분석을 실시한바 $Ydr=0.259{\times}exp(-0.0429T)+0.0560{\times}exp(-0.00106T)$ (time in weeks)로 나타났다. Qdr 값은 치료 직후부터 24주까지 1.51 전후로 거의 변화가 없었으며 이후 감소하여 52주 이후에는 1.17 전후로 거의 일정하였다. Qdra 값은 치료 직후부터 12주까지 1.10 전후이며 이후 감소하여 52주 이후에는 0.81 전후였다. 피폭 후 시간경과에 따른 Ydr값의 감소는 두 component exponential 모델을 잘 맞고 이 식을 이용하여 생물학적 선량측정이 가능하다. Qdr값 및 Qdra값은 피폭후 시간경과가 짧은 경우 피폭선량을 추정하는 지료로 사용할 수 있다.

• 한국환경성돌연변이발암원학회지
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• 제17권1호
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• pp.17-22
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• 1997

We observed the frequency of chromosome aberrations induced by UVB irradiations, and the suppressing effect of tannic acid on chromosome aberrations induced by UVB irradiations in CHL cells, which is a phenolic compound, a hydrolysate of tannin and a components of green tea. UVB doses used for the frequency of chromosome aberrations were from 0.2 to 1.6 KJ/m$^2$ and tannic acid concentrations were from 1.16 $\mu$g/ml to 37.50 $\mu$g/ml. For the observation of suppressing effect of tannic acid on UVB-induced chromosome aberrations, UVB dose was 1.6 KJ/m$^2$ and tannic acid concentrations were 1.0, 2.0, 4.0 $\mu$g/ml. In our study, tannic acid was treated for 24 hours in CHL, cells after UVB irradiation without S9 mix or for 6 hours with S9 mix. From this study, we obtained the following results : (1) The frequency of chromosome aberrations UVB induced were dose-dependently increased. (2) The tannic acid did not induce chromosome aberrations in cultured Chinese hamster cells. (3) UVB-induced chromosome aberrations were suppressed by tannic acid at every concentration from 1.0 $\mu$g/ml to 4.0 $\mu$g/ml with or without metabolic activation. These results suggest that the tannic acid acts as an inhibitor to UVB-induced clastogenicity of the cultured cell.

• Journal of Radiation Protection and Research
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• 제26권2호
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• pp.101-111
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• 2001

본 연구는 염색체 1, 2, 4, 7, 8, 9 및 21번 염색체의 DNA probe를 이용하여 2Gy의 방사선을 조사한 후 DNA 양을 감안한 기대치와 관찰치의 차이를 비교함으로서 각 염색체의 방사선에 대한 감수성을 평가하여 궁극적으로 방사선 피폭시 생물학적 선량계로서 FISH기법의 타당성을 평가하고자 하였다. 1번 및 4번 염색체의 경우 상호전좌와 이동원 염색체의 관찰치가 기대치보다 더 높게 나타났으며 이와 반대로 2, 7, 8 및 9번 염색체의 경우 상호전좌와 이동원염색체의 관찰치 모두 기대치보다 낮게 나타났다. 2번 및 4번 염색체의 경우 1번 염색체보다 더 많은 acentric fragment의 빈도를 나타내었다. 1, 2, 및 4번 염색체 3종을 조합했을 때 상호전좌의 경우 관찰치와 기대치는 세포 100개당 25.5 및 25.40으로 차이가 없었으며 이동원염색체의 경우 13.25 및 13.2로 역시 거의 차이가 없게 나타났다. 따라서 본 연구결과 방사선 피폭시 발생하는 염색체이상 빈도는 염색체마다 DNA 양에 비례해 나타나지 않을 수 있어 각 염색체마다 방사선 감수성에 차이가 있을 것으로 판단된다. 또한 방사선 피폭시 생물학적 선량계로서 1, 2 및 4번을 동시에 관찰 할 경우 염색체 FISH 법을 활용하기 위하여 적절한 염색체 조합이라고 판단된다.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 춘계 학술발표
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• pp.164-165
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• 2009

See Full Text

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2002년도 Current Trends in Toxicological Sciences
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• pp.66-66
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• 2002

• 한국환경보건학회지
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• 제21권3호
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• pp.67-76
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• 1995

The frequencies of chromosome aberrations and sister chromatid-exchanges in peripheral blood lymphocyte of 44 nurses handling anticancer drugs were compared with those in 44 age-match controls. The frequencies of dicentric chrdmosome were $2.4\times 10^{-3}$ in the exposed and $0.5\times 10^{-3}$ in the control. The frequencies of sister cromatid exchanges in the exposed were slightly higher (5.68 SCEs/cell) than those in the control (5.04 SCEs/cell). The frequencies of chromosome aberrations and sister cromatid exchanges were not associated with duration of drug handling and types of anticancer drugs, but associated with use of safety cover.

• Journal of Plant Biology
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• 제8권1_2호
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• pp.1-4
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• 1965

Beta-ray irradiation effects on structural changes of the chromosomes in root tip of rye, Secale cereale L., seedlings, particularly the frequency of chromosome bridge induction at anaphase stage treated with radioactive sulfur (S35) solutions were studied in this experiment. Among the four different concentrations of isotope solution, the lowest one, 0.4$\mu$c solution, has shown weak effect on the induction of chromosome aberration. On the other hand, higher concentration, 25.6$\mu$c solution, induced higher frequency of chromosome bridge induction as much as 4.3%. Concerning the relationship between the ages of after treatment and the ranges of concentration, the higher concentrations showed more pronounced effects than the lower ones.

• Toxicological Research
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• 제14권2호
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• pp.211-216
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• 1998

In order to evaluate the mutagenic potential of SDK(skin decontamination kit) produced by Agency for Defense Development(ADD), were performed Salmonella typhimurium reversion assay, chromosomal aberration test on chinese hamster ovarian cells and in vivo micronucleus assay using mouse bone marrow cells according to the established regulation of Korean Food and Drug Administration. In the reverse mutation test using Salmonella typhimurium TA98, TA100, TA1535 and TA1537 did not in-crease the number of revertant at any of the concentration tested in this study. SDK did not increase the number of cells having structural or numerical chromosome aberration in cytogenetic test. In mouse micronucleus test, no significant increase in the occurrence oj micro nucleated polychromatic erythrocytes were observed in ICR male mice intraperitoneally administered with SDK. These results indicate that SDK has no mutagenic effects under these experimental conditions.

• Toxicological Research
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• 제17권1호
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• pp.1-6
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• 2001

To determine whether ozone is genotoxic at environmentally relevant exposure level, B6C3F1 mice were exposed to 0.5 ppm ozone for 12 weeks, 6 hr/day. Chromosomal aberration, supravital micronucleus and hprt mutation assays were performed. The percentage of abnormal cells was significantly increased at 0.5 ppm ozone when compared to unexposed control in chromosome aberration assay. Significant increase in the frequencies of micro nucleated reticulocytes and 6-thioguanine-resistant ($TG^r$) lymphocytes was also observed in supravital micronucleus assay using peripheral blood and lymphocyte hprt mutation assay, respectively. The results indicate, that under our experimental conditions, 0.5 ppm ozone are genotoxic in exposed B6C3F1 mice.