• Title/Summary/Keyword: genetic toxicology

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Current Progress of Next Generation Battery of Toxicology-Cellular and Molecular Toxicology

  • Ryu, Jae-Chun;Kim, Youn-Jung
    • Molecular & Cellular Toxicology
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    • v.1 no.1
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    • pp.26-31
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    • 2005
  • The detection and the regulation of man-made synthetic chemicals and the establishment of toxicity that may pose a genetic hazard in our environment are subjects of great concern because of its close correlation between environmental contamination and human health. Since the tens of thousands of man-made chemicals that have been introduced into the environment in the last few decades must also be tested for their damaging effect on DNA, the agents that cause this damage must be identified.

Benchmark Dose Modeling of In Vitro Genotoxicity Data: a Reanalysis

  • Guo, Xiaoqing;Mei, Nan
    • Toxicological Research
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    • v.34 no.4
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    • pp.303-310
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    • 2018
  • The methods of applied genetic toxicology are changing from qualitative hazard identification to quantitative risk assessment. Recently, quantitative analysis with point of departure (PoD) metrics and benchmark dose (BMD) modeling have been applied to in vitro genotoxicity data. Two software packages are commonly used for BMD analysis. In previous studies, we performed quantitative dose-response analysis by using the PROAST software to quantitatively evaluate the mutagenicity of four piperidine nitroxides with various substituent groups on the 4-position of the piperidine ring and six cigarette whole smoke solutions (WSSs) prepared by bubbling machine-generated whole smoke. In the present study, we reanalyzed the obtained genotoxicity data by using the EPA's BMD software (BMDS) to evaluate the inter-platform quantitative agreement of the estimates of genotoxic potency. We calculated the BMDs for 10%, 50%, and 100% (i.e., a two-fold increase), and 200% increases over the concurrent vehicle controls to achieve better discrimination of the dose-responses, along with their BMDLs (the lower 95% confidence interval of the BMD) and BMDUs (the upper 95% confidence interval of the BMD). The BMD values and rankings estimated in this study by using the EPA's BMDS were reasonably similar to those calculated in our previous studies by using PROAST. These results indicated that both software packages were suitable for dose-response analysis using the mouse lymphoma assay and that the BMD modeling results from these software packages produced comparable rank orders of the mutagenic potency.

The Distributions of Three Genetic Polymorphisms in the Estrogen $Receptor-\alpha$ Gene in Korean Essential Hypertensives (한국인 본태성 고혈압군에서 에스트로젠 수용체-$\alpha$(유전자에 존재하는 다형성의 분포에 관한 연구)

  • Kim Ji Young;Kang Byung Yong;Lee Kang Oh
    • Environmental Analysis Health and Toxicology
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    • v.20 no.3 s.50
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    • pp.249-258
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    • 2005
  • Blood pressure, obesity and bone mineral density are multifactorial traits influenced by genetic factor. The purpose of this study was to clarify the association between three genetic polymorphisms in the estrogen receptor-$\alpha$ (ER -$\alpha$) gene and essential hypertension in korean population. One hundred and seventy-one people including 90 normotensives and 81 essential hypertentives were recruited. Among genetic polymorphisms studied, the Xba I RFLP in the intron 1 of this gene polymorphism was significantly associated with essential hypertension in women, suggesting the sexual dimorphism in genetic effect (P (<) 0.05). Further studied suggest that a larger sample size of this study are needed.

Validation of Photo-comet Assay as a Model for the Prediction of Photocarcinogenicity

  • Kim, Ji-Young;Koh, Woo-Suk;Lee, Mi-Chael
    • Toxicological Research
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    • v.22 no.4
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    • pp.423-429
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    • 2006
  • Recent reports on the photocarcinogenicity and photogerotoxicity of many compounds led to an increasing awareness for the need of a standard approach to test for photogenotoxicity. The comet assay has been recently validated as a sensitive and specific test system for the quantification of DNA damage. Thus, the objectives of this study are to investigate the utility of photo-comet assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-comet assays were performed using L5178Y $Tk^{+/-}$ mouse lymphoma cells on five test substances (8-methoxypsoralen, chlorpromazine, lomefloxacin, anthracene and retinoic acid) that demonstrated positive results in photocarcinogenicity tests. For the best discrimination between the test substance-mediated DNA damage and the undesirable DNA damage caused by direct UV absorption, a UV dose-response of the cells in the absence of the test substances was firstly fnalized. Out of 5 test substances, positive comet results were obtained for chlorpromazine, lomefloxacin, anthracene and retinoic acid while 8-methoxypsoralen found negative. An investigation into the predictive value of this photo-comet assay for determining the photocarcinogenicity showed that photo-comet assay has relatively high sensitivity. Therefore, the photo-comet assay with mammalian cells seems to be a good and sensitive predictor of the photocarcinogenic potential of new substances.

CHEMOPREVENTION OF COLON AND MAMMARY CANCER BY THE KOREAN FOOD STUFFS

  • Kim, Dae-Joong;Byeongwoo Ahn;Kang, Jin-Seok;Nam, Ki-Taek;Park, Mina;Shin, Dong-Hwan;Jang, Dong-Deuk
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10b
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    • pp.15-15
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    • 2001
  • In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz[$\alpha$]anthracene (DMBA).(omitted)

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CHEMOPREVENTION OF COLON AND MAMMARY CANCER BY THE KOREAN FOOD STUFFS

  • Kim, Dae-Joong;Byeongwoo Ahn;Kang, Jin-Seok;Nam, Ki-Taek;Park, Mina;Shin, Dong-Hwan;Jang, Dong-Deuk
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.58-58
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    • 2001
  • In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz[$\alpha$]anthracene (DMBA).(omitted)

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