• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.60-66
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• 2002

Aryl hydrocarbons, environmental contaminants accumulate in tissue and pose potential risk in human health. 2,3,7,8-Tertachlorodibenzo-p-dioxin (TCDD) is known as a most potent toxicant among aryl hydrocarbons. TCDD elicits numerous toxic responses in experimental animals and human, including hepatic carcinoma, pulmonary and skin tumor in adult rodents, craniofacial abnormality during mouse embryogenesis, chloracne, reproductive abnormality, immunotoxicity, endocrine effects in exposed humans.(omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.90-105
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• 2002

The dioxin- or aryl hydrocarbon receptor (AhR) is a member of the Per-Arnt-Sim family of nuclear transcription factors exhibiting a basic helix-loop-helix structure. In its non-ligated state the AhR is associated with hsp 90 and the immunophilin-type XAP2. Upon ligand binding the associated proteins are released, the receptor dimerizes with the AhR nuclear trans locator protein Arnt, and binds to XREs (xenobiotic-responsive elements) in the 5'-flanking region of responsive genes thus modulating their transcription.(omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.211.2-211.2
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• 2003

Saururus Chinensis Baill (Saururaceae) has been used as folk medicine for analgesics, beriberi, edema, hepatitis, and icterus, etc. Hepatoprotective effects of Saururus chinensis Baill (SCB) administration on function of the biochemical parameters in liver of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) treated rats were investigated. After 7 days from TCDD(1$\mu\textrm{g}$/kg) injection, SCB(200mg/kg) was administered into rats intraperitoneally for 4 week.s We examined the antioxidative enzymatic activity by measuring the level of AST and ALT in serum and SOD, Catalase, GPx, GSH and GSSG in liver tissue of rats. (omitted)

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.164-168
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• 2001

Abel et al. in Germany discovered a new dioxin-responsive gene, which has later been identified as rpt-1 (regulatory protein T-lymphocyte 1). While it is speculated that rpt-1 may play a role in signal transduction and carcinogenesis, its roles and functions remain unknown. The present study attempted to analyze functions of rpt-1 in human epithelial cells following the xenobiotic exposures. While German counterpart analyzed expressionn of rpt-1 in spleen and thymus cells from mouse and rat and characterizes molecular properties of the gene, our work mainly focused on analyzing function of rpt-1 in human skin cells. Expression of rpt-1 in human cells were analyzed by western and northern blot RT-PCR analysis. Expression of rpt-1 as well as Staf-50 in human cells with or without exposure to environmental pollutants were also analyzed by northern blot analysis, since Staf-50 is homologous with rpt-1 and found in human cells. To help study roles of rpt-1 in human cell system, retroviral vector system carrying rpt-1 gene under the CMV promoter were constructed and transfected. Cells overexpressing the gene after the transfection showed an increase of cell density and soft agar colony formations, as compared to the control cells, suggesting that rpt-1 may play a certain role in the transformation processes of human cells. While the expression of rpt-1 in spleen and thymus is known to be strong in the laboratory animals, both the basal and TCDD-induced expression of rpt-1 in the current cellular system remained insignificant. It is speculated that the expression pattern of rpt-1 may be tissue- and species-specific. The present study demonstrated a strong expression of rpt-1 protein in the brain of SD rat model. Since there is no previous report on the expression of rpt-1 in the brain tissue, the result may play a significant role in understanding dioxin-induced neurotoxicities in the future. The present study provides an opportunity to understand a role of rpt-1 in human cell system and suggest a possible lead and basis for the future study of dioxin-induced neurotoxicities.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.782-787
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• 2002

This study was carried out to investigate the protective effect of chitosan on lipid peroxidation and key lipid parameters in Sprague-Dawley rat (SO rat) accutely exposured to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Male SO rats received single intraperitoneal (ip) injection of TCDD (40 j.lg/kg), and were given diet containing 3 or 5% chitosan for 4 weeks from 1 week before TCDD treatment. The gain in body weight was less in group treated with TCDD than in CON group, while that of Ch/H+ TCDD group (5% chitosan diet) increased. The decrease in liver and testis weight caused by TCDD was prevented by high dietary intake of chitosan (5% chitosan). Serum (total cholesterol, triglyceride, HDL-C, and LDL-C) and liver lipid parameters (total lipid, total cholesterol, and triglyceride) were significantly elevated in TCDD-induced rats, but these parameters excluding HDL-C were significantly reduced in high dietary intake of chitosan (5% chitosan). These findings suggest that chitosan is believed to be a possible protective effect against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in rat.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.1-6
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• 2006

A methodology for the syntheses of carboxanilides using solid support of 4-chloro-3-nitorbenzophenone oxime resin 5 was developed. Condensation of 4-chloro-3-nitorbenzophenone resin 6 with hydroxylamine hydrochloride salt gave oxime resin 5. The reaction of oxime resin 5 with dioxin and oxathiin derivatives 7a-d afforded the corresponding polymer-bound dioxin and oxathiin derivatives 9a-d. These polymer-bound resins 9a-d were treated respectively with aniline in the presence of acetic acid resulted in the corresponding dioxin carboxanilides 10a-d (yield, 5%-quantitative).

• Korean Journal of Pharmacognosy
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• v.32 no.2 s.125
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• pp.121-127
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• 2001

The effect of bear bile on 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD)-induced hepatotoxicity was investigated in 6-week-old C57BL/6 male mice. Bear bile (100 mg/kg or 500 mg/kg) was administered orally daily for 4 weeks, respectively. From the second week, $10\;{\mu}g/kg$ of TCDD was administered to the bear bile-treated animals orally once a week for 3 weeks (a total of $30\;{\mu}g/kg$). There were no specific clinical findings and significant body weight changes in all groups. Although the livers in TCDD-treated mice appeared a severe hypertrophy and many necrotic foci, and changed to yellow-brown color in gross findings, these lesions were remarkably reduced by bear bile administration. The elevated serum activities of alanine transaminase, aspartate transaminase, alkaline phosphatase, and lactate dehydrogenase due to TCDD were significantly decreased by bear bile treatment (P<0.05). The lipid peroxidation induced by TCDD was significantly prevented by bear bile administration (P<0.05). In histological examinations, there were a moderate necrosis of hepatic cells around central veins, severe cytoplasmic vacuolizations, inflammatory cell infiltrations, and remarkable fatty changes in the liver of TCDD-treated animals. However, the lesions were dose-dependently inhibited by the bear bile treatments. These findings indicate that bear bile may have a protective effect against TCDD-induced hepatotoxicity in mice.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.123-126
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• 2002

Pollutants that are persistent, bioaccurnulative, and toxic have been linked to numerous adverse effects in human and animals, PBTs include heavy metals, polychlorinated biphenyls (PCBs), dioxins, polycyclic aromatic compounds (PACs) in addition to pesticides. This study focuses on toxic effects of the PBTs except pesticides on insects. Eight PBTs were selected from subgroups: three heavy metals (Pb, Hg, and Cd), two PCB mixtures (Aroclor mixtures 1 and 2), 2,3,7,8-tetrachlorodibenzo-p-dioxin, two monophenols (4-octylphenol and 4-nonylphenol), and tetrabutyltin, Beet armyworm, Spodoptera exigua, was used as test target insect species. Three physiological markers (metamorphosis, immune reaction, and follicle patency) were assessed in each exposure to different doses of the PCBs. Heat-shock proteins as molecular markers were also analyzed in response to the PCBs. All tested PBTs were toxic to metamorphosis from larvae to pupae when they were applied with diet. Two PCB mixtures were the most toxic compounds in this assay by giving significant toxicity at 0.005 ppm, while others had from 10 to 1000 ppm. Dioxin (0.1 ppb), tetrabutyltin (0.1 ppb), Pb (10 ppb), and Hg (0,01 ppb) were potent to inhibit immune reactions analyzed by inducing phenoloxidase activity and blocked phospholipase $A_2$ enzyme, Tetrabutyltin and dioxin significantly induced follicle cell patency, but their effects were lower than that of endogenous juvenile hormone, Dioxin, Pb, Hg, and Cd could induce the expression of heat shock proteins that were detected by immunoblotting against human HSP70 monoclonal antibody. HSP78 and HSP80 were upregulated in response to the PBTs. This expression was detected from the fat body and epidermis at as fast as 4h after injection. All these results clearly suggest that PBTs give significant ecotoxicity to insects that are valuable organisms in our environment.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.179-185
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• 2000

In this study, we examined the movement of chlorophenol as a precursor of the dioxin in the after-combustion to minimize the creation and emission of dioxin in a municipal waste incinerator. The CPs was injected to the electric incinerator in temperature $300{\sim}500^{\circ}C$, using $N_2$ gas to control the reaction time, The oxygen quantity supplied into the $CP_s's$ isomer combustion was added with the value of experience formula. When the space velocity in reactor was 60~80/sec, the removal efficiency of CP was obtained in the presence of Mo-V catalyst and non catalyst. The efficiency in non-catalyst was 74% to 80% mono-CP, di-CP 55~66%, tri-CP 50~58%, while mono-CP 90~99.9%, di-CP 96~97%, tri-CP 76~99% in a catalyst. Consequently, it was shown that these were 20~30% more efficienct than those.

• Analytical Science and Technology
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• v.17 no.2
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• pp.184-191
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• 2004

In this study, the separation of toxic dioxin 2,3,7,8-congeners by DB-5MS and SP-2331 GC columns which are widely used in HRGC/HRMS analysis was examined. Through the dioxin analysis of column performance check standard solution and fly ash sample, the isomer specific separation of 2,3,7,8-substituted dioxins from tetra to hexa-isomers on DB-5MS and SP-2331 columns were studied. The effect of I-TEQ value by these columns was also studied. The total concentrations of toxic dioxins for the column performance check standard solution were 508.4 ng/mL analyzed by DB-5MS and 515.8 ng/mL analyzed by SP-2331, respectively. The I-TEQ value obtained by both columns was shown to be almost equivalent for the column performance check standard solution and fly ash sample.