• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.138-138
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• 2004

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.79-79
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• 2004

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.105-105
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• 2004

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.101-102
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• 2001

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2005.05a
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• pp.40-50
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• 2005

[ $\cdot$ ] Risk is a product of Hazard and Exposure $\cdot$ Cannot assume that nanomaterials are the same as their bulk counterpart $\cdot$ Each particle-type should be tested on a casse-by-case basis

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.99-104
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• 2003

• 축산식품과학과 산업
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• v.4 no.2
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• pp.2-6
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• 2015

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.4
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• pp.295-305
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• 2001

Protein kinase C (PKC) is known to play a pivotal role in neoplastic transformation cells and its high expression is often found in a variety of types of tumors including oral cancer. While PKC is associated with the altered signal transduction pathway of the tumor cells, it is still unclear which isoform is involved in the carcinogenesis process. Since the cellular distributions and the roles of PKC are isoform-specific, it is very important to identify the specific target molecules to improve our understanding of the carcinogenesis processes. Thus, the present study attempted to perform chemical carcinogen-induced neoplastic transformation of human epithelial cells and analyze the specific isoform of PKCs involved in the cellular transformation. The study analyzed overall PKC responses upon MNNG(N-Methyl-N'-nitro-N-nitroso guanidine) exposure with [$^3H$] PDBu binding assay. PKC translocation was observed at high doses of MNNG treatment in the presence of extracellular calcium. Such effects were not observed in the absence of extracellular calcium. Translocational effects with exposure of MNNG was further enhanced in the presence of hydrocortisone. The result suggests that the type of PKC involved may be $Ca^{2+}$-dependent classical isoform and steroid hormone enhances PKC activation. Among cPKC isoforms examined, only $PKC-{\alpha}$ and r showed significant translocation of protein levels from cytosolic fraction to membrane fraction, as analyzed by immunoblot. $PKC-{\varepsilon}$ in nPKC class showed an inch·eased translocation, but other forms in this class did not show the effect. None of isoforms in aPKC class was affected by MNNG treatment. The study demonstrated that there was a certain specificity in the patterns of isoform induction follwong chemical carcinogen exposure and helped identify all the types of PKC isoforms expressed in human epithelial cells. It was revealed that PKC isoforms were activated in an early resonse to chemical carcinogen, suggesting that PKC be associated with carcinogenesis process from an early stage in this particular cell system. The study will contribute to improving our understanding of chemical-induced carcinogenesis in human cells and may provide a scientific basis to introduce the specific PKC inhibitors as an anticancer drug of epithelial cell-origin cancers including oral cancer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.398-404
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• 1993

In order to examine the anticarcinogenic effects of garlic juice on the hamster buccal pouch carcinogenesis induced by 9, 10-dimethyl-1, 2-benzanthracene (DMBA) totally 135 hamster.0.5% DMBA in mineral oil were painted onto the hamster buccal pouch three times a week on 50th, 70th and 90th day, while normal saline, 1% and 3% garlic juice were forced to oral tube feeding. Tumor cell induction could be seen on 50th experimental day, presumed to early carcinogenic inductive stage. And the tumor cells proliferated rapidly thereafter, so 70th and 90th experimental day were chosen for the comparison of anticarcinogenic effect of garlic juice. The every specimens were fixed in 10% buffered formalin for routine histopathological observation and also fixed in Carnoy's solution for the BrdU immunohistochemital detection of S-stage tumor cell distribution during the carcinogenesis. There showed more or less increased anticarcinogenic effect of garlic juice against DMBA induced hamster buccal pouch carcinoma, increased comparing to the control group showing invasive tumor growth after all histopathologically, BrdU immunoreactivity on normal pouch mucosa epithelium, representing the mitotic status, more decreased in the garlic juice feeding group than the control group. Meanwhile the neoplastic epithelium of all experimental groups showed much increased BrdU immunostaining irregularly.

• Environmental Mutagens and Carcinogens
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• v.8 no.1
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• pp.35-46
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• 1988

출생직후부터 새끼쥐에 유발시킨 납중독이 중추의 특정 신경계에 미치는 신경독성의 선택성 여부를 알아보고자 하였다. 특정 신경계의 한 예로 모노아민성 신경계를 선택하여 납중독의 지표로 모노아민성 신경계의 효소인 MAO (mono-amine oxidase)의활성을 측정하였으며, 비특정 조직의 지표로 Na+K+-ATPase의 활성을 측정하였다. Wistar계의 흰쥐에서 태어난 새끼들에게 출생직후부터 전실험기간을 통해 0.05% 혹은 0.2% 초산납 (PbAc2)용액을 식수로 공급하여 납중독을 유발시켰다. 생후 2, 4, 6 및 8주된 새끼쥐의 MAO 및 Na+K+-ATPase활성을 대뇌, 간뇌, 중뇌, 뇌교-연수 및 다섯부위에서 각기 측정하였다.