• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.105-109
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• 2000

The purpose of this study is to investigate on the water quality of the upper region of Wonchun stream located in Suwon city by chemical analysis and EROD-microbioassay methods using rat hepatoma cell line H4IIE. The water samples were collected at 6 sampling sites from sept. to Nov. 1999 and determined the quantitative toxic effects. Higher levels of BO $D_{5}$, CO $D_{Cr}$ and CO $D_{Mn}$ were determined at M6 site where the influent contains domestic and industrial wastewater. EROD activity of water samples was ranged from 3.43$\pm$0.08 to 9.05$\pm$0.10 pmol/mg protein/min. High correlation with EROD activities and COD values was observed. From the results, the upper region of Wonchun stream water area was presumed to be highly polluted with various persistent organic chemicals.s.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2085-2087
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• 2003

A new interacting multiple model (IMM) method based on intelligent input estimation (IIE) is proposed for tracking a maneuvering target. In the proposed method, the acceleration level of each sub-filter is determined by IIE using the fuzzy system, which is optimized by the genetic algorithm (GA). The tracking performance of the proposed method is compared with those of the input estimation (IE) technique and the adaptive interacting multiple model (AIMM) method in computer simulations.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.93-99
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• 2002

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.364-368
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• 1987

The addition reactions of thioglycolic acid, benzenethiol and benzylmercaptan to ${\beta}-acetyl-{\beta}-benzoylstyrene$ were investigated. ${\beta}-Acetyl-{\beta}-benzoylstyrene$ derivatives easily underwent addition reactions with thioglycolic acid, benzenethiol, and benzylmercaptan to form five(2-acetyl-2-benzoyl-1-phenylethyl) thioglycolic acid derivatives (IIa-IIe), five (2-acetyl-2-benzoyl-1-phenylethyl)benzenethiol (IIIa-IIIe) derivatives and five (2-acetyl-2-benzoyl-1-phenylethyl)benzylmercaptan derivatives (IVa-IVe), respectively.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.11-17
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• 2000

There are among the most relevant toxic emissions from incinerators such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs). Induction of cytochrome P4501A1 catalyzed 7-ethoxyresorufin O-deethylase(EROD) activity in mammalian cell culture(EROD bioassay) is thought to be a selective and sensitive parameter used for the quantification of dioxin-like components. In this study, the toxic emissions from several school waste incinerators were evaluated by determination of CYPIA catalytic activity and cytotoxicity using cell culture microbioassay. The incinerator residue and soil samples were collected from the schools located in Kyunggi province from April to June 1999. The samples were extracted in a Soxhlet apparatus using toluene for 20 hours. In order to clean-up, concentrated crude extracts were applied to basic alumina column. The EROD activities of extracts in the H4IIE cells were from 1.91$\pm$0.32 ng-TEQ/g to 24.54$\pm$3.48 ng-TEQ/g of biochemical-TEQ value. In soil samples, CYP1A catalytic activity was 0.09~0.64 ng-TEQ/g. EROD bioassay, seems to be a useful short-term bioassay when information about the biological response of complex environmental samples is needed. Although further study is needed, these results indicate that the potent toxic emissions are produced from school waste semi-incinerators.

• Toxicological Research
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• v.23 no.2
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• pp.127-133
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• 2007

Metformin is a drug used to lower blood sugar levels in patients with type 2 diabetes via activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK). The primary objective of this study was to investigate whether metformin at the pharmacologically effective concentrations affects the expressions of ${\gamma}$-glutamylcysteine synthetase and phase II antioxidant genes in the H4IIE cell. Treatment of the cells with either metformin or 5-aminoimidazole-4-carboxamide riboside (AICAR) abrogated tert-butylhydroxyquinone (t-BHQ) induction of ${\gamma}$-glutamylcysteine synthetase, a rate limiting enzyme of GSH synthesis. The ability of t-BHQ to induce glutathione S-transferases (GSTs), a major class of phase II detoxifying enzymes that playa critical role in protecting cells from oxidative stress or electrophiles, was also inhibited by the agents. Transcriptional gene repression by metformin was verified by the GSTA2 promoter luciferase assay. Moreover, either metformin or AICAR treatment significantly decreased t-BHQ-dependent induction of other GSTs (i.e., $GST{\mu}$ and $GST{\pi}$ forms). Taken together, our data indicate that metformin treatment may result in the repression of ${\gamma}$-glutamylcysteine synthetase and glutathione S-transferase genes possibly via AMPK activation.

• The Korea Journal of Herbology
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• v.22 no.1
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• pp.7-12
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• 2007

Objectives : In Alzheimer's disease(AD), free radical oxidative stress caused by amyloid beta-peptide may lead to DNA damage, neuronal dysfunction, neurotoxicity and cell death, Hwangryunhaedok-tang(HHT) is traditionally used for the treatment of pyrogenetic diseases. To develop a new anti-AD drug from natural herb, HHT was selected and extracted in this study. Methods : The antioxidant activities of HHT water extract powder were examined by hydroxyl radical-induced DNA strand nicking assay, and antioxidative enzymes expression assay in H4IIE cell. In addition, HHT was examined for the inhibitory effect on the acetylcholinesterase(AChE) using by Ellman's coupled assay. Results: The HHT exhibit DNA protective effect in the hydroxyl radical-induced DNA Strand nicking assay, mRNA expression of superoxide dismutase and glutathione peroxidase were recovered at a normal level by HHT treatment in H4IIE cell. Furthermore, water extract of HHT showed inhibitory effect on AChE activity. Conclusion : These results suggest that HHT may be effective in delaying and preventing AD progression related to the free radical-induced DNA damage and AChE activity.

• Radiation Oncology Journal
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• v.29 no.3
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• pp.174-180
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• 2011

Purpose: To evaluate the radiotherapy treatment outcome of patients in stage IE and IIE nasal natural killer/T-cell lymphoma. Materials and Methods: From August 1999 to August 2009, 46 patients with stage IE and IIE nasal natural killer/T-cell lymphoma were treated by definitive radiotherapy and chemotherapy. 33 patients were treated with chemotherapy followed by radiotherapy (CT + RT) and they received 50.4 Gy in 28 fractions. 13 patients were treated with concurrent chemoradiotherapy (CCRT) and they received 40 Gy in 20 fractions. Results: The median follow-up period was 4.6-137.6 months (median, 50.2 months) for all patients. The 4-year overall survival was 68.6% and 4-year disease free survival (DFS) was 61.9%. The 4-year locoregional recurrence free survival was 65.0%, and 4-year distant metastasis free survival (DMFS) was 66.2%. For patients treated with CT + RT, 15 patients (45.5%) achieved complete response after chemotherapy, and 13 patients (39.4%) achieved partial response. 13 patients (81.8%) achieved complete response after radiotherapy, and 6 patients (18.2%) achieved partial response. For patients treated with CCRT, 11 patients (84.6%) achieved complete response, and one patient (7.7%) achieved partial response. In univariate analysis, presence of cervical lymph node metastasis was only significant prognostic factor for DFS and DMFS. Conclusion: This study did not show satisfactory overall survival rate and disease free survival rate of definitive radiotherapy and chemotherapy for stage IE and IIE nasal natural killer/T-cell lymphoma. For patients with cervical lymph node metastasis, further investigation of new chemotherapy regimens is necessary to reduce the distant metastasis.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.91-99
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• 2002

• Toxicological Research
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• v.7 no.2
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• pp.231-238
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• 1991

The pesticide and carcinogen ethylene dibromide(EDB) is metabolized both by cytosolic GSH S-transferase and by microsomal mixed function oxygenase. Cytochrome P-450 IIE1 appears to be major enzyme to metabolize EDB.EDB is activated to a mutagen by enzymatic conjugation with glutathione (GSH). Such activation is an exception to the general mode of detoxification via GSH S-transferase action. The primary DNA adduct (>95) is S-[2-(N7-guanyl)ethyl] GSH and a minor adduct is S-[2-(N7-guanyl)ethyl]cysteine, which is excreted in the urine and may serve as a biomarker of damage.