• 제목/요약/키워드: preventive effect

검색결과 2,704건 처리시간 0.039초

Chemopreventive effect of Ginkgo biloba extract on breast cancer: Regulation of estrogen level

  • Oh, Seung-Min;Kim, Yun-Hee;Chung, Kyu-Hyuck
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.282.2-283
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    • 2002

  • In situ and circulating estrogen is the most important endocrine hormone that promotes the growth of hormone-dependent breast cancer. Consequently. decrease of estrogen on in situ and circulation can inhibit breast cancer. Estrogen is mainly produced by the ovary in premenopausal women and by peripheral tissues such as adipose tissues in postmenopausal women. The cytochrome p450 (CYP19), aromatase. is a key enzyme in the synthesis of estrogen hormones. (omitted)

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Carbamate 중독에 대한 감초, 흑두 추출액의 예방효과에 관한 연구 (A Study on the Preventive Effect of Extract of Glycyrrhizae Radix and Glycine Semen on NAC Intoxication)

  • 신일순;민경진;강회양
    • 한국환경보건학회지
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    • 제19권2호
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    • pp.61-68
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    • 1993

  • This study aimed at evaluating the preventive effect of Glycyrrhizae Radix and Glycine Semen Extract (GGE) against NAC intoxication. NAC is widely used pesticide in many countries and derivative of carbamats and GGE is well-known antidote to some kinds of toxicants which was referenced from oriental medicine text. The results obtained were as follows: 1) After injecting NAC (100,140 mg/kg), determined Ch.E activities decrease 44.77~50.86% for all experimental groups at one hour after exposure, and were gradually recovered in the course of time. 2) In toxicity test of GGE, there were no sign of death or poisoning up to 5000 mg/kg of GGE for p.o. in mice. From this, we suggest that the LD$_{50}$ of GGE would be above 5000 mg/kg. 3) The Ch.E activity in control group was 471.43 $\pm$ 4.85 luff, group I was 215.27 $\pm$ 23.13 IU/l, group II and group III were 304.03 $\pm$ 9.03 IU/l, 433.81 $\pm$ 21.73 IU/l, respectively. Compare to the control group with experimental group I, remarkable difference revealed (p< 0.01), but the Ch.E activities of group II and III were similar to those of control group. This is indicate that GGE possess a potent activity of recovering Ch.E. GGE had a very remarkable preventive effect on NAC toxicity, and it was able to know that Ch.E activity dramatically increased according to GGE dosage increasing. 4) When GGE and NAC were administered by p.o. simultaneously, LD$_{50}$ and confidence intervals of each group were as follows: the control group: 270 mg/kg, 234.99~310.23 mg/kg, group I and II (GGE 500 mg/kg, 1000 mg/kg by p.o.): 310 mg/kg, 271.69~353.71mg/kg, and 325 mg/kg, 285.09~370.50 mg/kg, respectively. In the comparison with the control group, the protective index was 1.1 and 1.2, respectively. From the above result, GGE has reactivation effect to decreasing Ch.E activity induced by exposure to NAC. Furthermore, GGE shows a preventive effect on NAC intoxication.

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암면에 의한 세포독성 및 변이원성의 실험실적 평가 (In Vitro Assessment of Cytotoxicity and Mutagenicity of Rock Wool Fibers)

  • 홍윤철;이관희
    • Journal of Preventive Medicine and Public Health
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    • 제30권3호
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    • pp.555-566
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    • 1997

  • This study was carried out to evaluate the cytotoxicity of rock wool fibers(RWFs) such as cell division disturbance, chromosomal and DNA damage, and mutagenicity using cultured cells. RWFs were the man made mineral fibers. In order to find the correlation between the cytotoxicity of RWFs and the phagocytic capacity of cells, the phagocytic processes were observed using scanning electron microscope. Cell division disturbance by RWFs was evaluated by the formation of multinucleated giant cells. The chromosomal damage was evaluated by the micronucleus formation. For the evaluation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation was measured utilizing calf thymus DNA. Mutagenicity was determined by the point mutation of HGPRT and the effect of RWFs on cell transformation was also observed. 1. Compared with the results of chrysotile, RWFs were no or little effect on the cell growth according to the results done by the tests of cell proliferation inhibition and relative plating efficiency. 2. The frequency of multinucleated giant cell formation was increased by the treatment of RWFs and it was dose-dependent. However, the effect of RWFs was weaker than that of chrysotile. 3. The number of micronuclei formed in the RWFs treated cells was between those of cells treated with chrysotile and those of untreated cells. 4. The 2 fold increase in the formation of 8-OH-dG in calf thymus DNA was observed in the cells treated with RWFs in the presence of $H_2O_2$. On the other hand, chrysotile had no effect on the 8-OH-dG formation. 5. RWFs had no effect on the HGPRT point mutation and cell transformation. These results showed that RWFs could induce chromosomal damage, cell division disturbance and oxidative DNA damage in the RWFs treated cells.

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