• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.330-335
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• 2014

Objectives: To evaluate the mutagenicity of lithium carbonate, a bacterial reverse mutation(Ames) test was carried out using four strains of S. typhimurium(TA1535; TA1537; TA98; and TA100) and one strain of E. coli(WP2uvrA). Materials: This was carried out in a dose range from 312.5 to $5,000{\mu}g/plate$ in triplicate with and without S9 activation, which is the most commonly used metabolic activation system supplemented by a post-mitochondrial fraction prepared from the livers of rodents treated with enzyme-inducing agents such as Aroclor 1254 or a combination of phenobarbitone and ${\beta}$-naphthoflavone. Results: No significant increases in the number of revertants were observed under the conditions examined in this study. Conclusions: Based on the above observations, it can be concluded that lithium carbonate has no mutagenic activity. Despite the results, it can have an effect by inducing acute oral toxicity, eye irritation and acute aquatic toxicity. Based on this study, we suggest that future studies should be directed toward chronic, carcinogenic testing and other related areas.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.14.1-14.6
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• 2012

Objectives: The root barks of Periploca sepium Bge. (P. sepium) has been used in traditional Chinese medicine for healing wounds and treating rheumatoid arthritis. However, toxicity in high-doses was often diagnosed by the presence of many glycosides. The potential mutagenicity of P. sepium was investigated both in vitro and in vivo. Methods: This was examined by the bacterial reverse mutation (Ames) test using Escherichia coli WP2uvrA and Salmonella typhimurium strains, such as TA98, TA100, TA1535, and TA1537. Chromosomal aberrations were investigated using Chinese hamster lung cells, and the micronucleus test using mice. Results: P. sepium did not induce mutagenicity in the bacterial test or chromosomal aberrations in Chinese hamster lung cells, although metabolic activation and micronucleated polychromatic erythrocytes were seen in the mice bone marrow cells. Conclusions: Considering these results, it is suggested that P. sepium does not have mutagenic potential under the conditions examined in each study.

• Journal of Physiology & Pathology in Korean Medicine
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• v.36 no.4
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• pp.113-119
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• 2022

SU-Eohyeol pharmacopuncture(SUEP) was developed by adding Cervi Pantotrichum Cornu to Jungsongouhyul pharmacopuncture. This genotoxicity evaluation was performed to evaluate the mutagenic potential of the test substance SUEP agent using histidine, which requires strains of Salmonella typhimurium (TA98, TA100, TA1535, TA1537), and tryptophan, which requires Escherichia coli (WP2uvrA) strain in the presence and absence of metabolic activation. According to the results of the dose range finding study conducted prior to the main study, the dose levels of the test substance in the main study were determined as 100, 50, 25, 12.5, 6.25%, and positive and negative controls were established. As a result of the main study, the mean number of revertant colonies compared to negative controls was less than 2-fold at all dose levels of SUEP in all strains with and without metabolic activation. In the positive control group, the mean number of revertant colonies for each strain was markedly increased by more than two times compared to the negative control group. Based on the result of this study, the test substance, SUEP did not show any indication of mutagenic potential under the conditions of this study.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.6
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• pp.88-95
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• 2020

Currently, Fiber-Reinforced Plastic (FRP) composite materials are used in many industrial fields, owing to their superior stiffness and specific strength compared to metals. However, there are issues with FRP inefficiency, due to low productivity of such materials, environmental problems they pose and long curing times needed. Trying to address these issues, research was conducted towards the development of a FRP composite material with excellent properties and short production time, introducing a curing method using a UV lamp. Four types of composite materials were prepared, cured with catalyst or UV (CZ: Catalyst + ZNT 6345, CR: Catalyst + RF 1001 MV, UVZ: Photoinitiator + ZNT 6345, and UVR: Photoinitiator + RF 1001 MV). Examination of the chemical and mechanical properties of these composites showed that UV-cured materials performed better than the catalyst-cured ones. These results indicate that the production process of FRP composite materials can be simplified by using a UV lamp for curing, resulting in composite materials with the same quality, but reduced production time by about 70% compared to currently used practices. This advancement will contribute greatly to the composite material industry.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.2
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• pp.37-45
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• 2007

We have measured the spectral transmittances of UV blocking soft contact lenses, regular soft contact lenses and regular RGP lenses using the method suggested in ANSI Z80.20 standard. In order to evaluate visible light transmitting and UV blocking characteristics, we have calculated transmittances by integrating over the specific spectral ranges, i.e., visible light, UVA, UVB and UVC. We found that mean transmittances of visible light for all three categories were over 90.0 % which could be considered as within acceptable range for a contact lens. The transmittance of the UVA and UVB radiation for the UV blocking soft lenses except some cases was within UVR (Ultraviolet radiation) transmittance standard. The UV blocking ability of regular soft and RGP lenses was poor as rather expected. These results will be expected to assist clinical opticians and practitioners in utilizing the transmittance characteristics about the contact lens.

• Molecular & Cellular Toxicology
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• v.3 no.1
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• pp.53-59
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• 2007

This study was conducted to evaluate the mutagenic potential of dimethyl isophthalate (DMIP) using Ames bacterial reverse mutation test, chromosomal aberration test and mouse lymphoma $tk^{+/-}$ gene assay. As results, in Ames bacterial reversion assay, DMIP was tested up to the concentration of 5,000 ${\mu}g$/plate and did not induce mutagenicity in Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537, and Escherichia coli WP2uvrA with or without metabolic activation (S9 mix). Using cytotoxicity test, the maximal doses of DMIP for chromosomal aberration assay were determined at 1,250 ${\mu}g/mL$, which was a minimum precipitation concentration ($IC_{50}>1,940\;{\mu}g/mL$ or 10 mM) and at 155 ${\mu}g/mL$ ($IC_{50}:155\;{\mu}g/mL$) in the presence and the absence, respectively, of S9 mix. DMIP in the presence of S9 mix induced statistically significant (P<0.001) increases in the number of cells with chromosome aberrations at the dose levels of over 250 ${\mu}g/mL$, when compared with the negative control. However, DMIP in the absence of S9 mix did not caused significant induction in chromosomal aberrant cells. In MLA, DMIP at the dose range of 242.5-1,940 ${\mu}g/mL$ in the presence of S9 mix induced statistically significant increases in mutation frequencies related to small colony growth, whereas any significant mutation frequency was not observed in absence of S9 mix. From these results, it is conclusively suggested that dimethyl isophthalate may be a clastogen rather than a point mutagen.

• Toxicological Research
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• v.23 no.3
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• pp.245-251
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• 2007

Water extract of Cordyceps militaris grown upon Protuetja dreujtarsis (CMPD) was examined for the genetic toxicity-bacterial mutagenicity, chromosome aberration, and micronucleus formation. For mutagenicity assay, bacterial reversion test with Salmonella typhimurium TA98, TA100, TA1535, TA 1537, and E. coli WP2uvrA were performed. The extract at the concentrations of $50{\sim}5,000{\mu}g/plate$ did not induce mutagenicity at all. Chromosome aberration test was performed by using Chinese lung (CHL) cells. There was no significant chromosome aberration in CHL cells with S-9 mixture at the concentrations of $312.5{\sim}1,250{\mu}g/ml$ of the extract and without S-9 mixture at the concentrations of $1.2{\sim}19.5{\mu}g/ml$ of the extract. For micronucleus test, ICR mice were treated with the extract at the dose of 0.5, 1, and 2g/Kg. The frequencies of the micronucleated polychromatic erythrocytes (MNPCE) in bone marrow preparations of the extract-treated group were not increased compared to the untreated control group. Taken together, our results show that water extract of CMPD did not induce any harmful genotoxicity.

• Archives of Pharmacal Research
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• v.24 no.4
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• pp.307-311
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• 2001

The activation of NF-$\kappa$B induced by kojic Acid, an inhibitor of tyrosinase for biosynthesis of melanin in melanocytes, was investigated in human transfectant HaCaT and SCC-13 cells. These two keratinocyte cell lines transfected with pNF-$\kappa$B-SEAP-NPT plasmid were used to determine the activation of NF-$\kappa$B. Transfectant cells release the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the NF-$\kappa$B activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selective marker of geneticin resistance. NF-$\kappa$B activation was measured in the SEAP reporter gene assay using a fluorescence detection method. Kojic Acid showed the inhibition of cellular NF-$\kappa$B activity in both human keratinocyte transfectants. It could also downregulate the ultraviolet ray (UVR)-induced activation of NF-$\kappa$B expression in transfectant HaCaT cells. Moreover, the inhibitory activity of kojic Acid in transfectant HaCaT cells was found to be more potent than known antioxidants, e.g., vitamin C and N~acetyl-L-cysteine. These results indicate that kojic Acid is a potential inhibitor of NF-$\kappa$B activation in human keratinocytes, and suggest the hypothesis that NF-$\kappa$B activation may be involved in kojic Acid induced anti-melanogenic effect.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.373-373
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• 2010

광촉매능을 갖는 $TiO_2$는 국내외적으로 많은 연구가 진행되고 있다. 빛의 조사로 발생하는 다양한 물리 화학적 촉매특성이 환경정화 뿐만 아니라 및 에너지 흡수차단 기능도 갖고 있어 최근 주목을 받고 있다. 응용분야로 초친수성 유리제품, 필터, 살균기능의 의료용 부품소재, 고효율 수소생산 및 태양전지 등에 활용성이 커서 친환경에너지 소재로 각광을 받고 있다. 본 연구에서는 초친수성 자동차의 사이드미러 개발을 위해 유리표면에 초친수성 $TiO_2$를 코팅하 고 그의 특성을 평가하였다. 특히, 이종밴드갭을 갖는 복합구조 $TiO_2/Cr_2O_3$/Cr 박막을 스퍼터링법으로 증착하여 중간층인 $Cr_2O_3$의 역할을 고찰하였다. 제조된 박막의 결정구조는 thin film형 X-선회절기(XRD)를 사용하여 분석하였으며, 박막의 표면 미세구조는 FE-SEM(Field Emission Scanning Electron Microscope)와 AFM(Atomic Force Microscope)으로, 화학구조는 XPS(X-ray Photoelectron Spectroscope)로 분석하였다. 친수성 평가는 실온 분위기에서 접촉각 측정기(Topcon-UVR2)를 사용하여 평가 하였으며 이때 조사되는 UV는 파장이 365nm이다. $Cr_2O_3$(비정질)/Cr박막위에 제조된 $TiO_2$ 박막은 균일한 anatase-$TiO_2$가 성장했으나, Cr, $Cr_2O_3$(결정질)박막위에 제조 된 $TiO_2$ 박막은 anatase상과 rulile상이 혼합된 형태로 성장하였다. $TiO_2$/Cr, $TiO_2/Cr_2O_3$(비정질)/Cr, $TiO_2/Cr_2O_3$(결정질)/Cr박막은 UV조사 1시간 만에 $10^{\circ}$ 이하의 초친수성을 나타내었다. 이종 밴드갭을 갖는 $TiO_2/Cr_2O_3$(비정질)/Cr박막은 40시간까지 친수성을 유지하는 결과를 나타냈다.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.87-89
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• 2018

Flavisolibacter tropicus $LCS9^T$ was isolated from a soil sample collected from tropical zone within the Ecorium of the National Institute of Ecology in Seocheon, central-western Korea. In this study, we report the complete genome sequence of the bacterium Flavisolibacter tropicus $LCS9^T$, which possesses a circular chromosome comprised of 5, 940,863 bp with the G + C mol content of 41.5%. The genome sequence annotation showed that the complete genome includes 5,075 genes, 337 pseudogenes, and 59 rRNA genes. The radiation resistance genes such as excinuclease UvrABC complex and UvdE were present in the genome.