• Korean Journal of Veterinary Service
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• v.26 no.4
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• pp.345-359
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• 2003

A number of toxicants have been incriminated as a causing hepatic disease. Among many detrimental injury, alcohol has been noted for hepatitis, fatty liver, fibrosis, and hepatic cirrhosis. The purpose of this study was to develop animal model for hepatic fibrosis in pigs fed ethanol, and to search for a new anti-fibrogenic agent via this model. Twelve male Landrace pigs were divided into 3 groups of 4 animals each. Group 1, 2 and 3 were fed with active ceramic water only, ceramic water + liquid diet containing 15% ethanol and normal tap water + liquid diet containing 15% ethanol for 12 weeks, respectively. At week 12, all pigs were immediately sacrificed for collection each tissue and blood. Serologically, serum ALT and AST levels were significantly reversed in group 2, as compared to group 3. They were normal range in pigs of group 1. Microscopically, macrovesicular lipid droplets and moderate hepatocellular necrosis were evident in the tap water + ethanol fed group 3. However, the active ceramic water treated group 1 showed normal architecture. Moreover, in group 2, mild fatty changes and necrosis were observed in hepatocytes. Collagen fibers were increased in spaces surrounding periportal and interlobular connective tissues in the group 3 of tap water + ethanol, but collagen synthesis and its thickness of fibrotic septa connecting portal tracts were markedly reduced in the group 2 of ceramic water + ethanol. Myofibroblasts were detected mainly in the interlobular connective tissues of pig liver of group 3 treated ethanol and tap water. Few to no myofibroblasts were observed in groups 1 and 2. CYP2E1 was not or rarely detected in group 1 fed ceramic water. However, group 2 showed slightly activation of CYP2E1 in the area of pericentral vein, while CYP2E1 was significantly activated in group 3 fed tap water and ethanol. Based on the above data, we believe that we have developed a unique alcohol induced fibrosis model in pig, which will be useful in developing anti-fibrotic agents and drugs. Furthermore, the active ceramic water used in our study had an inhibitory and may be protective against ethanol induced hepatic toxicity and fibrosis.

• Water for future
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• v.27 no.1
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• pp.69-77
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• 1994

As the standard of living improves, the amount of synthetic detergent consumption greatly increases. Detergents which are not treated in the sewer treatment processes, flow into rivers or waterstreams and accelerate the pollution of the surface water resources. Detergents contain lots of toxicants. And it is difficult to evaluate gross toxicity of each toxicant in thereceiving water. In the study, the acute toxicity of the synthetic detergents for home laundering and kitchen use were monitored with daphnia magna and photobacterium phosphoreum. Seven kinds of detergents were tested to evaluate the acute toxicity. The mean 24hr, 48hr-LC50 of the synthetic detergent for home laundering were 4.25%, 2.50% and these for kitchen use were 2.01%, 1.36% respectively. And the mean 5min, 15min-EC50 of the synthetic detergent for home laundering were 1.83%, 1.02%.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.421-426
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• 2010

Benzene is one of volatile environmental pollutants to induce asthma and allergy in respiratory system. The airway epithelium is a physical barrier to inhaled toxicants and particulates. However, the effect of benzene in lung epithelial cell viability has not been elucidated. Thus, this study was conducted to investigate the effect of benzene on apoptosis in A549 cells, lung epithelial cell line. In this study, benzene decreased cell viability of A549 cells in a dose-dependent manner (> $10{\mu}M$). Benzene-induced decrease of cell viability was blocked by the treatment of antioxidants (vitamin C and NAC). Indeed, benzene induced lipid peroxide formation in A549 cells. Benzene decreased Bcl-2 expression but increased Bax expression in A549 cells. In addition, benzene also increased the cleaved form of caspase-3. In conclusion, benzene induced apoptosis via oxidative stress in cultured epithelial cells.

• Development and Reproduction
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• v.6 no.1
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• pp.25-30
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• 2002

Endocrine disruptors have been reported to adversely affect reproduction and embryonic development in wild animals. One of the major abnormalities observed during early embryonic development is cellular fragmentation. In this study, we exposed mouse preimplantation embryos to PCB, BPA and DDT in vivo or in vitro. Embryos exposed to endocrine disrupter showed a variety of morphological abnormalities such as fragmentation, irregular blastomeres and cracked empty zonae pellucidae. To investigate the levels of gene expression related which genes contribute to apoptosis in preimplantation mouse embryos, we carried out the reverse transcription polymerase chain reaction to assess mRNA levels far apoptotic gene. Bcl-2, bad and bax expression levels were compared between control group and endocrine disrupter treated group. Expression level of bcl-2 gene tended to be lower in the treated group than control while expression levels of bad and bax genes were higher in the treated group. Results of this study may provide a useful tool for rapidly screening developmental toxicants in preimplantation embryos exposed to endocrine disruptors in vivo or in vitro.

• Fire Science and Engineering
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• v.17 no.3
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• pp.61-73
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• 2003

Most of the accidents occurred from the chemical plants are related to the catastrophic gas release events when the large amount of toxic materials is leaked from its storage tank or transmitting pipe lines. In this case, the greatest concerns are how the spreading behaviors of leakages are depended on the ambient conditions such as air stability and other environmental factors. Hence, we have focused on the risk assessments and consequential analysis for chlorine as an illustrative example. As appeared in the result, Fire & Explosion Index depicted it a bit dangerous with presenting the comprehensive degrees of hazard 90.7. And as a result of Phast6.0/ALOHA, the trends of each scenario appeared considerably identical although there are some differences in the resulting effects according to the input data for the Gas Model. The consequence analysis is performed numerically based on the dense gas mode. In the future, using more correct input data, material properties, and topographical configuration, the method of this research will be useful for the guideline of the risk assessment when the release of toxicants breaks out.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.419-423
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• 2006

In this study, acute toxicity of four pesticides (diazinon, iprodione, fenproparthrin, and myclobutanil) to Chinese bleak, Aphyocypris chinensis, and to study their adverse effects were conducted in static systems. The 96-hr $LC_{50}$ values were determined, as well as 95% confidence limits. The 96-hr $LC_{50}$ values of these chemicals derived for Chinese bleak were rank ordered from the most toxic to the least toxic technicals as follows: Fenproparthrin (0.003 mg $L^{-1}$)>Myclobutanil (9.1 mg $L^{-1}$)>Diazinon (14.1 mg $L^{-1}$)>Iprodione (31.8 mg $L^{-1}$), The data presented in this study indicate the acute toxicity tests carried out on only one fish species may lead to erroneous determination of water quality criteria and classification of test chemicals for environmental management and regulatory purpose. Therefore, more studies comparing the susceptibility of a variety of fish species to various toxicants are needed.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.79-86
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• 2017

Aflatoxin $M_1$ ($AFM_1$) after its bioconversion from aflatoxin $B_1$ in animal liver becomes the part of milk while heavy metals get entry into milk and milk products during handling in the supply chain. Aflatoxin $M_1$ and heavy metals being toxic compounds are needed to be monitored continuously to avoid any ailments among consumers of foods contaminated with such toxicants. Thirteen commercially available infant formula milk (IFM) brands available in Pakistani markets were analyzed for the quantitative determination of $AFM_1$ and heavy metals through ELISA and atomic absorption spectrophotometer, respectively. $AFM_1$ was found positive in 53.84% samples while 30.76% samples were found exceeding the maximum EU limit i.e. $0.025 {\mu}g/kg$ for $AFM_1$ in IFM. Heavy metals lead (Pb) and cadmium (Cd) were found below the detection limits in any of the sample, whereas the concentrations of iron (Fe), zinc (Zn) and nickel (Ni) ranged between 45.40-97.10, 29.72-113.50 and <$0.001-50.90 {\mu}g/kg$, respectively. The concentration of Fe in all the tested brands was found in normal ranges while the concentrations of Zn and Ni were found exceeding the standard norms. Elevated levels of $AFM_1$, Zn and Ni in some of the tested IFM brands indicated that a diet completely based on these IFM brands might pose sever health implications in the most vulnerable community i.e., infants.

• Safety and Health at Work
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• v.11 no.2
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• pp.152-158
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• 2020

Background: The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) was developed to enhance chemical classification and hazard communication systems worldwide. However, some of the elements such as building blocks and data sources have the potential to cause "disharmony" to the GHS, particularly in its classification results. It is known that some countries have developed their own lists of classified chemicals in accordance with the GHS to "standardize" the classification results within their respective countries. However, the lists of classified chemicals may not be consistent among these countries. Method: In this study, the lists of classified chemicals developed by the European Union, Japan, Malaysia, and New Zealand were selected for comparison of classification results for carcinogenicity, germ cell mutagenicity, and reproductive toxicity. Results: The findings show that only 54%, 66%, and 37% of the classification results for each Carcinogen, Mutagen and Reproductive toxicants hazard classes, respectively are the same among the selected countries. This indicates a "moderate" level of consistency among the classified chemicals lists. Conclusion: By using classification results for the carcinogenicity, germ cell mutagenicity, and reproductive toxicity hazard classes, this study demonstrates the "disharmony" in the classification results among the selected countries. We believe that the findings of this study deserve the attention of the relevant international bodies.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.1047-1054
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• 2003

Molecular chaperones have a crucial role in the folding of nascent polypeptides in endoplasmic reticulum. Some of them are known to be sensitive to the modification by electrophilic metabolites of organic pro-toxicants. In order to identify chaperone proteins sensitive to alkyators, ER extract was subjected to alkylation by 4-acetamido-4 -maleimidyl-stilbene-2,2 -disulfonate (AMS), and subsequent SDS-PAGE analyses. Protein spots, with molecular mass of 160, 100, 57 and 36 kDa, were found to be sensitive to AMS alkylation, and one abundant chaperon protein was identified to be protein disulfide isomerase (PDI) in comparison with the purified PDI. To see the reactivity of PDI with cysteine alkylators, the reduced form ($PDI_{red}$) of PDI was incubated with various alkylators containing Michael acceptor structure for 30 min at $38^{\circ}C$ at pH 6.3, and the remaining activity was determined by the insulin reduction assay. Iodoacetamide or N-ethylmaleimide at 0.1 mM remarkably inactivated $PDI_{red}$ with N-ethylmaleimide being more potent than iodoacetamide. A partial inactivation of $PDI_{oxid}$ was expressed by iodoacetamide, but not N-ethylmaleimide (NEM) at pH 6.3. Of Michael acceptor compounds tested, 1,4-benzoquinone ($IC_{50}, 15 \mu$ M) was the most potent, followed by 4-hydroxy-2-nonenal and 1,4-naphthoquinone. In contrast, 1,2-naphthoquinone, devoid of a remarkable inactivation action, was effective to cause the oxidative conversion of $PDI_{red}$ to $PDI_{oxid}$. Thus, the action of Michael acceptor compounds differed greatly depending on their structure. Based on these, it is proposed that POI, one of chaperone proteins in ER, could be susceptible to endogenous or xenobiotic Michael acceptor compounds in vivo system.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.4
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• pp.399-406
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• 2016

Early life neuronal exposure to environmental toxicants has been suggested to be an important etiology of neurodegenerative disease development. Perfluorohexanesulfonate (PFHxS), one of the major perfluoroalkyl compounds, is widely distributed environmental contaminants. We have reported that PFHxS induces neuronal apoptosis via ERK-mediated pathway. Imperatorin is a furanocoumarin found in various edible plants and has a wide range of pharmacological effects including neuroprotection. In this study, the effects of imperatorin on PFHxS-induced neuronal apoptosis and the underlying mechanisms are examined using cerebellar granule cells (CGC). CGC were isolated from seven-day old rats and were grown in culture for seven days. Caspase-3 activity and TUNEL staining were used to determine neuronal apoptosis. PFHxS-induced apoptosis of CGC was significantly reduced by imperatorin and PD98059, an ERK pathway inhibitor. PFHxS induced a persistent increase in intracellular calcium, which was significantly blocked by imperatorin, NMDA receptor antagonist, MK801 and the L-type voltage-dependent calcium channel blockers, diltiazem and nifedipine. The activation of caspase-3 by PFHxS was also inhibited by MK801, diltiazem and nifedipine. PFHxS-increased ERK activation was inhibited by imperatorin, MK801, diltiazem and nifedipine. Taken together, imperatorin protects CGC against PFHxS-induced apoptosis via inhibition of NMDA receptor/intracellular calcium-mediated ERK pathway.