Intra- and inter-laboratory study of microplate reverse mutation test evaluating 8 chemicals

Seongmoo Heo,Myoung Jun Kim,Suhyun Nam,Seoung Hoon Park,Jeong Ja Oh,Young-Shin Chung 한국실험동물학회 2021 한국실험동물학회 학술발표대회 논문집 Vol.2021 No.7

This study was conducted to establish the technology for bacterial reverse mutation test using 384-well microplates and liquid media instead of solid agar in order to evaluate the mutagenicity of test articles with limited amounts. The important advantage of this test method was considered that the usage of S9 fraction prepared from rat liver was smaller in comparison with the Ames test using solid agar. Five bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, TA1537 and Escherichia coli WP2 uvrA) recommended in OECD 471 were used to evaluate 8 chemicals including 6 mutagens and 2 non-mutagens. All experiments were performed using Ames MPFTM Penta II kits (Xenometrix, Switzerland). Three independent laboratories participated in the intra-and inter-laboratory study. Results from this study were compared with reference mutagenicity data (NTP or published data). Five out of six mutagens were evaluated to be positive, and the one mutagen to be negative. Two non-mutagens were determined to be negative in microplate tests. Both the intra- and the inter-laboratory study showed the 87.5% concordance of the test results. It was concluded that a microplated reverse mutation test may be a compatible test method for the animal welfare as well as for the limited amount of substances. Funding Source: This research was supported by a grant (19182MFD390) from Ministry of Food and Drug Safety in 2019.Disclosure Statement: None of the authors have any conflicts of financial interest to declare.

In vivo Genotoxicity Assessment of Matrine and the Water Extract of Sophorae Radix Using a Comet Assay

Heo, Seongmoo,Lee, Jiyeon,Jeon, Hyoungwoon,Kim, Myoungjun,Chung, Young-Shin The Korean Society of Food Hygiene and Safety 2021 한국식품위생안전성학회지 Vol.36 No.2

본 연구는 고삼 물추출물과 주 성분인 마트린의 유전독성 유발능을 마우스 간세포 및 혈구세포에서 체내 단세포전기영동 시험법을 사용하여 평가하였다. OECD TG 489에서 정하고 있는 체내 알카리코멧 시험법(in vivo alkanine Comet assay)을 수컷 마우스를 사용하여 수행하였다. 고삼물추출물의 투여 용량은 한계 용량을 포함하도록 체중 대비 1,000와 2,000 mg/kg으로 하였다. 마트린의 세 투여용량은 50, 100, 200 mg/kg으로 정하였고, 최고 투여용량은 용량 설정시험을 통하여 설정하였다. 음성대조물질과 시험물질은 경구로 3회 투여하였고, 양성대조물질(ethyl methanesulfonate, EMS)은 2회 투여하였다. 마지막 투여 후 3-4시간 내에 간조직과 혈액을 채취하였고 단세포전기영동을 알카리 조건에서 수행하였다. 코멧 시험 결과, 고삼 물추출물과 마트린에 의한 체중의 변화가 관찰되지 않았으며, 간세포와 혈구세포에서 통계적으로 유의성 있는 유전자 손상을 유발하지 않았다. 따라서, 본 연구조건에서 고삼 물추출물과 마트린은 유전독성 유발능이 없는 것으로 사료된다. The genotoxic potentials of the water extract of Sophorae Radix (WSR) and matrine as a major compound were investigated in murine hepatocytes and blood cells using single-cell gel electrophoresis. According to the test guidelines of OECD TG 489, an in vivo alkaline Comet assay was performed using male mice. The treatment doses of the WSR were 1,000 and 2,000 mg/kg body weight to include the limiting dose. The three test doses for matrine were 50, 100, and 200 mg/kg, and the maximum dose was estimated from a dose range-finding test. The negative control and test articles were administered three times by oral gavage, and the positive control (ethyl methanesulfonate, EMS) was administered twice. Within 3-4 h after the last treatment, the liver tissue and blood were collected, and single-cell electrophoresis was performed under alkaline conditions. The in vivo Comet assay showed no changes in body weights during the treatments with the test articles. The WSR and matrine did not induce significant DNA damage in the liver and blood cells of mice compared to the vehicle treatment. In conclusion, matrine and the WSR may not have genotoxic potential.

안전한 지급결제 어플리케이션 개발을 위한 PCI PA-DSS 준수 방안 연구

허성무(Seongmoo Heo) 한국정보보호학회 2010 情報保護學會誌 Vol.20 No.6

정보통신 기술 및 전자상거래의 발전으로 지급결제 서비스는 성장을 거듭하고 있으나, 그 중심에 있는 전자지급결제의 위험 역시 계속해서 발견되고 있다. 지급결제카드산업의 정보보호를 위해 설립된 PCI SSC에서는 지급결제 어플리케이션개발에 대한 보안 표준인 PCI PA-DSS를 통해서 소프트웨어 벤더가 안전한 개발을 수행하도록 요구하고 있으나, 준수 대상인 기업 관점에서 참조 가능한 정보가 절대적으로 부족한 상황이다. 본 논문에서는 관련 보안 표준과의 연계 및 소프트웨어 개발 생명 주기를 통한 개발 절차 관리 방안을 통해, 소프트웨어 벤더가 PCI PA-DSS를 효과적으로 준수할 수 있는 방안을 제안한다.

REPS Input Shaft corrosion 침투 개선 설계

허성무(Seongmoo Heo),김준혁(Junhyuk Kim),박선홍(Sunhong Park) 한국자동차공학회 2023 한국자동차공학회 부문종합 학술대회 Vol.2023 No.5

반도체 패권을 둘러싼 한국ㆍ중국ㆍ미국간 경쟁 양상에 대한 연구 : 국제정치 및 경제 이론 활용

허성무 ( Seongmoo Heo ) 한국통상정보학회 2018 통상정보연구 Vol.20 No.4

4차 산업혁명의 핵심인 반도체 산업에서 한국은 메모리반도체 강자로 자리잡았다. 메모리반도체 시장에서의 패권 다툼은 신흥 도전국의 시장 진입 시도와 이를 억제하려는 패권국의 노력이 다양한 형태로 나타나고 있다. 국가안보와 연계된 반도체 산업의 특성상 기업간 경쟁 차원을 넘어, 각국 정부는 전략적으로 개입하여 산업정책과 무역정책을 구사하고 있다. 한국이 메모리반도체 패권을 유지하는 데 필요한 실질적인 전략수립을 위해, 본고에서는 세력전이 이론, 동맹전이 이론, 헤게모니 쇠퇴 이론, 전략무역 이론에 입각하여 메모리반도체 시장에서의 시장 지배자와 시장 진입자간 패권경쟁 양태를 살펴본다. 경제 이론과 국제정치 이론을 접목시켜 볼 때, 현상 유지를 원하는 시장 지배자인 패권국은 후발주자 진입 억제를 위해 무역제재, 인수합병 저지, 배타적 가격 전략, 사다리 걷어차기 등 전략을 구사한다. 현상 타파를 원하는 시장 진입자인 신흥 도전국은 자국 산업 경쟁력 제고를 위한 세제 지원, 보조금 지급, 무역 보복, 인재 스카웃, 인수합병, 동맹 참여 등을 시도한다. 시장 환경이 결코 한국의 메모리반도체 패권유지에 유리한 방향으로 순조롭게 흘러가지 않는 국면에서, 국가안보를 확보하기 위한 정부의 외교적 노력의 필요함을 주장했다. Korea has been a dominating presence in the memory semiconductor industry which has played a key role in the 4th Industry Revolution Era. There are many forms of competition for hegemony, such as the attempts of new challengers to enter the market and the efforts of super powers to deter them. Semiconductor industry is not just a matter of economy, but a matter of national security, which leads to government engagement in trade and industrial policy. This research is written in order to offer ideas for an adequate action plan that the Korean semiconductor industry needs to implement. This research focuses on hegemony competition in the memory semiconductor market between dominant firms and market entering firms using recent examples, and is based on the power transition theory, alliance transition theory, hegemonic decline theory and strategic trade theory. According to economic and international political theories, dominant firms - as super powers - want status quo. So they block exporting important semiconductors to competitors, stop M&A's by competitors, use limit pricing strategy and kick away the ladder, which can deter challengers from entering their market. Challengers want to change the regime. As a result, they reduce corporate taxes, offer subsidies for firms, implement retaliation on trade, scout for top talented engineers and scientists, try to merge other firms and join alliances in order to enhance their competitiveness in the market. Under the unfavorable circumstances for Korean firms to maintain dominance, this research emphasizes the importance of diplomatic efforts to guarantee national security.

마이크로플레이트를 이용한 8종 화학물질의 복귀돌연변이 평가

김명준 ( Myoung Jun Kim ),허성무 ( Seongmoo Heo ),남수현 ( Suhyun Nam ),백승민 ( Seng-min Back ),박성훈 ( Seong Hoon Park ),오정자 ( Jeong Ja Oh ),정영신 ( Young-shin Chung ) 한국동물실험대체법학회 2021 동물실험대체법학회지 Vol.15 No.1

This study was conducted to establish the technology for bacterial reverse mutation test using 384-well microplates and liquid media instead of solid agar in order to evaluate the mutagenicity of test articles with limited amounts. The important advantage of this test method was considered that the usage of S9 fraction prepared from rat liver was smaller in comparison with the Ames test using solid agar. Five bacterial strains (S. typhimurium TA98, TA100, TA1535, TA1537 and E. coli WP2 uvrA) recommended in OECD TG 471 were used to evaluate 8 chemicals including 6 mutagens (Allyl chloride, 4-amino-2-nitrophenol, ethylene glycol dimethyl ether, benzo[α]pyrene, 7,12-dimethylbenzanthracene, 8-hydroxyquinoline) and 2 non-mutagens (dioctyl phthalate, sulfisoxazole). All experiments were performed using Ames MPFTM Penta II kits (Xenometrix, Switzerland). Three independent laboratories participated in the intra-laboratory and inter-laboratory studies. Results from this study were compared with reference mutagenicity data (NTP or published data). In results of this study, five out of six mutagens were evaluated to be positive, and the one mutagen (ethylene glycol dimethyl ether) to be negative. Two non-mutagens were determined to be negative in microplate tests. Both the intra-laboratory and the inter-laboratory study showed the 87.5% concordance in the overall results. It was concluded that a microplated reverse mutation test may be a compatible test method for the animal welfare as well as for the limited amount of substances.