• Food Science of Animal Resources
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• v.39 no.1
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• pp.84-92
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• 2019

Listeria monocytogenes is a major cause of serious foodborne illness in the dairy foods. Although Caenorhabditis elegans model is well established as a virulence model of pathogenic bacteria, its application on L. monocytogenes is critically unclear. The objective of this study was to carry out an evaluation of L. monocytogenes toxicity using C. elegans nematode as a simple host model. We found that C. elegans nematodes have high susceptibility to L. monocytogenes infection, as a consequence of accumulation of bacteria in the worms' intestine. However, L. innocua, which is known to be non-toxic, is not accumulate in the intestine of worms and is not toxic similarly to Escherichia coli OP50 known as the normal feed source of C. elegans. Importantly, immune-associated genes of C. elegans were intensely upregulated more than 3.0-fold when they exposed to L. monocytogenes. In conclusion, we established that C. elegans is an effective model for studying the toxicity of L. monocytogenes and we anticipate that this system will result in the discovery of many potential anti-listeria agents for dairy foods.

• Korean Journal of Medicinal Crop Science
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• v.27 no.3
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• pp.173-185
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• 2019

Background: Galgeun-tang used in traditional Korean medicine, is a mixture of the medicinal plants Cinnamomi Ramulus, Ephedrae Herba and Puerariae Radix, and has been prescribed for the treatment of various ailments, including fever. Although the use of traditional medicinal herbs to treat diseases has recently increased, their safety and toxicity profiles incompletely elucidated. Thus, we evaluated Galgeun-tang's toxicity in male and female Sprague-Dawley rats. Methods and Results: Galgeun-tang (1,000, 2,000 and 4,000 mg/kg) was orally administered to rats for 13 weeks, and then, they were maintained for 4 weeks without administration (recovery period). Their clinical signs, and hematological and urinary properties, were monitored. The results showed that Galgeun-tang administeration slightly increased serum creatinine, urea nitrogen and, aspartate aminotransferase levels. Additionally, 2,000 and 4,000 mg/kg Galgeun-tang significantly increased urinary bilirubn and protein levels of male and female rats, which were restored during the recovery period. Conclusions: The no-observed-adverse-effect level of orally administered Galgeun-tang was 4,000 mg/kg in both female and male rats, and no target organs were identified. In addition, 400 mg/kg was found to be the no-observed-effect level for toxicity under the study conditions.

• Korean Journal of Veterinary Pathology
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• v.1 no.2
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• pp.91-96
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• 1997

General steps in the discovery and development of novel drugs in the United States are presented. The first step is the discovery of novel drugs. Brief histories and mechanisms of a few novel drugs in the American market are outlined. In this presentation preclinical animal toxicologic studies (drug safety evaluateion) are emphasized in regard to drug development. When preclinical animal studies have defined the toxicity and the doses at which it occurs an Investigational new Drug Application (IND) is submitted to the Food and Drug Administration (FDA) An IND notifies the FDA the intention to begin testing a novel drug in human subjects.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.645-648
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• 2011

Hydrazine which has been used as monopropellant shows high performance, but because of its high toxicity research for new green propellant that could replace hydrazine is going on. Ionic liquid propellant that is one of the green propellant has lower toxicity, higher specific impulse, and higher density than hydrazine. To design the thruster which use Hydroxylamine Nitrate (HAN), one of ionic liquid propellant, as a propellant, a quantity of catalyst for full decomposition of a propellant is needed. In this study, reference point for HAN thruster design could be suggested through a design of a small scale thruster which used HAN propellant, and propellant decomposition capability evaluation with characteristic velocity efficiency.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.409-412
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• 2013

Curcumin (Cum) has been reported to have potential chemo-preventive and chemotherapeutic activity through influencing various processes, inducing cell cycle arrest, differentiation and apoptosis in a series of cancers. However, the poor solubility of Cum limits its further applications in the treatment of cancer. We have previously reported Cum-loaded nanoparticles (Cum-NPs) prepared with amphilic methoxy poly(ethylene glycol)-polycaprolactone (mPEG-PCL) block copolymers. The current study demonstrated superior antitumor efficacy of Cum-NPs over free Cum in the treatment of lung cancer. In vivo evaluation further demonstrated superior anticancer effects of Cum-NPs by delaying tumor growth compared to free Cum in an established A549 transplanted mice model. Moreover, Cum-NPs showed little toxicity to normal tissues including bone marrow, liver and kidney at a therapeutic dose. These results suggest that Cum-NPs are effective to inhibit the growth of human lung cancer with little toxicity to normal tissues, and could provide a clinically useful therapeutic regimen. They thus merit more research to evaluate the feasibility of clinical application.

• Korean Journal of Environmental Biology
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• v.29 no.1
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• pp.23-30
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• 2011

In this study, the Comet assay (evaluation of DNA damage) used the fish hepatocellular carinoma cell, PLHC-1, was tried to the sediment extract obtained from freshwater to understand its applicability as a tool for monitoring sediment toxicity. In parallel, induced EROD (7-ethoxyresorufin- O-deethylase) activity and DNA damage (TEM values) in PLHC-1 cells were measured for establishing the tandem endpoints of the PLHC-1cell test to test the ecotoxicity of sediment. Among several study sites in a small river passed through downtown and industrial park area, one of them, site B, showed a higher level of EROD activity and DNA damage than other sites. It indicates that a tandem endpoints of PLHC-1 cells could be useful tools for assessing the toxicity of sediment. The sensitivity of Comet assay with PLHC-1 cells was a little higher than that with a blood cell of frog tadpoles to the solvent extract of sediment. According to the results, a PLHC-1 cell-Comet assay could be used as a useful tool for evaluating ecotoxicity of the freshwater sediment. In addition, more detailed studies are needed to the contaminated site.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.17-40
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• 2000

Cytotoxicity assays using artificial skins have been proposed as in vitro alternatives to minimize animal ocular and dermal irritation testing. Accordingly, the responses of artificial skins to the well-characterized chemical irritants toluene, glutaraldehyde, and sodium lauryl sulfate (SLS), and the nonirritant polyethylene glycol were studied. The evaluation of the irritating and non-irritating test chemicals was also compared with the responses observed in human dermal fibroblasts and human epidermal keratinocytes grown in a monolayer culture. The responses monitored included an MTT mitochondrial functionality assay. In order to better understand the local mechanisms involved in skin damage and repair, the production of several mitogenic proinflammatory mediators, interleukin-l$\alpha$, 12-HETE, and 15-HETE, was also investigated. Dose-dependent increases in the levels of かIn and the HETEs were observed in the underlying medium of the skin systems exposed to the two skin irritants, glutaraldehyde and SLS. The results of the present study show that both human artificial skins can be used as efficient in vitro testing models for the evaluation of skin toxicity and for screening contact skin irritancy.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.657-662
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• 2012

Mercaptoacetic acid (MAA) and mercaptopropionic acid (MPA) capped ZnS:Mn nanocrystals were synthesized and their physical characteristics were examined by XRD, HR-TEM, EDXS, and FT-IR spectroscopy. The optical properties of the MPA capped ZnS:Mn nanocrystals dispersed in aqueous solution were also measured by UV/Vis and solution photoluminescence (PL) spectra, which showed a broad emission peak around 598 nm (orange light emissions) with calculated relative PL efficiency of 5.2%. Comparative toxicity evaluation of the uncoordinated ligands, MAA and MPA, with the corresponding ZnS:Mn nanocrystals revealed that the original ligands significantly suppressed the growth of wild type E. coli whereas the ligandcapped nanocrystals did not show significant toxic effects. The reduced cytotoxicity of the conjugated ZnS:Mn nanocrystals was also observed in NIH/3T3 mouse embryonic fibroblasts. These results imply that potential toxicities of the capping ligands can be neutralized on ZnS:Mn surface.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2583-2585
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• 2016

Objectives: To evaluate efficacy and toxicity in patients with advanced lung cancer, including non-small cell and small cell variants (NSCLC and SCLC), treated with thalidomide plus chemotherapy. Methods: Fourteen patients with advanced lung cancer were scheduled to receive chemotherapy combined with thalidomide. All patients in this study received thalidomide (100 mg orally per night before sleeping, produced by Changzhou Pharmaceutical Factory Co.Ltd) after the start of chemotherapy for at least 14 days. Chemotherapy was administered according to the condition of patients. After at least 14 days of treatment, efficacy and toxicity were evaluated. Results: There were 6 female and 8 male patients with advanced lung cancer recruited into this study, including 2 with SCLC and 12 with NSCLC. The median age was 56.7 (44-65) years. Progressive disease was observed in 12 patients (12/14), and stable disease in 2 (2/14). Grade 1 to 2 myelosuppression was observed in 4/14 patients, and Grade 1 to 2 elevation of hepatic enzymes was recorded in 5/14 patients. Adverse effects on the gastrointestinal tract were documented in 2/14 patients, all beingGrade 1. No Grade 3-4 toxicity was recorded. No treatment related deaths occurred. Conclusions: Our results demonstrate that thalidomide combined with chemotherapy is mildly effective and safe for treating patients with advanced lung cancer. However, further evaluation of this combination is warranted.

• Journal of the Korean Society of Safety
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• v.17 no.1
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• pp.61-67
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• 2002

The toxic gases released from a fire can be classified as asphyxiants such as carbon monoxide, and irritants such as hydrochloric acid, etc. It is recognized that the combustion characteristic of interior upholstery is one of the important factors to determine the severity of indoor fires. In this study, several of the mostly used interior upholsteries including wallpaper, veneer board, curtain and floor cover, were selected to be evaluated by using the method of NES 713. The toxicity indices of the experimental samples, which indicate their toxic potentials in a fire were lowered in the order of Wallpaper (Flame Retardant) 8.5>Floor Cover(Hard) 4.8>polyurethane 4.3>Floor Cover(Soft) 3.5>PVC 2.8> Veneer Board 2.3> Floor Cover(flame retardant) 2.1>Wallpaper(Promulgation) 1.4>Curtain 0.9. It is concluded that, among all the tested upholsteries, wallpaper (flame retardant) would release the largest quantity of Toxic gases in a fire.