p53 tumor suppressor의 활성을 조절하는 세포내 기구

황은성 한국생화학분자생물학회 1999 생화학분자생물학회 소식 Vol.19 No.3

Lipofuscin Granule Accumulation Requires Autophagy Activation

황은성,송선범,Woosung Shim 한국분자세포생물학회 2023 Molecules and cells Vol.46 No.8

Lipofuscins are oxidized lipid and protein complexes that accumulate during cellular senescence and tissue aging, regarded as markers for cellular oxidative damage, tissue aging, and certain aging-associated diseases. Therefore, understanding their cellular biological properties is crucial for effective treatment development. Through traditional microscopy, lipofuscins are readily observed as fluorescent granules thought to accumulate in lysosomes. However, lipofuscin granule formation and accumulation in senescent cells are poorly understood. Thus, this study examined lipofuscin accumulation in human fibroblasts exposed to various stressors. Our results substantiate that in glucose-starved or replicative senescence cells, where elevated oxidative stress levels activate autophagy, lipofuscins predominately appear as granules that co-localize with autolysosomes due to lysosomal acidity or impairment. Meanwhile, autophagosome formation is attenuated in cells experiencing oxidative stress induced by a doxorubicin pulse and chase, and lipofuscin fluorescence granules seldom manifest in the cytoplasm. As Torin-1 treatment activates autophagy, granular lipofuscins intensify and dominate, indicating that autophagy activation triggers their accumulation. Our results suggest that high oxidative stress activates autophagy but fails in lipofuscin removal, leaving an abundance of lipofuscin-filled impaired autolysosomes, referred to as residual bodies. Therefore, future endeavors in treating lipofuscin pathology-associated diseases and dysfunctions through autophagy activation demand meticulous consideration.

네트워크 분석법을 이용한 군납업체 선정에 관한 연구

황은성,제두호,조재희 한국방위산업학회 2014 韓國防衛産業學會誌 Vol.21 No.2

본 연구는 국방분야에서 기준 미달의 부품과 원자재들을 사용하는 등 하자발생 가능성이 높은 취약업체를 분별해 내고 군수품 조달 시스템에 가장 중요한 영역을 차지하는 납품업체 선정과정에 보다 합리적인 안을 제시하고자 수행되었다. 이를 위하여 다기준하 합리적인 의사결정방법인 네트워크 분석법을 기반으로한 전략적 평가모델을 수립하였으며 중요성이 대두되는 방탄복을 대상으로 사례연구를 진행하여 수립된 모델의 실무적 적용 가능성을 확인하였다. 과학적 방법을 적용한 이러한 업체선정 과정은 다기준하 평가된 결과를 신뢰성 있는 데이터로 종합적으로 전환하여 의사결정자에게 공정하고 합리적인 대안을 우선순위별로 제시해 준다는 점에서 큰 의의가 있다. 본 연구가 군납업체 선정과정에서 투명성과 공정성을 확보하고 나아가 국민적 신뢰 회복과 함께 군 전투력 증강에 크게 기여하기를 기대한다. With the development of military defense technologies, exports of Korea’s defense industry have been increasing over the years. However, there have also been corruption cases related to military supply. This study identified corruption-vulnerable manufacturers in the military field that use substandard materials and parts, which are prone to defects. This study also suggested a more reasonable military procurement vendor selection process. For such reasons, we established a strategic evaluation model based on network analysis, which is the most rational decision-making method under multiple criteria, and verified the model’s practical applicability with a case study on body armor. This scientific method would help decision-makers come up with rational alternatives fairly and transparently. This study provided guidelines for ensuring fair and transparent selection of a military purveyance firm and for increasing combat power.

특집 : 학술지의 국제화와 연구부정

황은성 한국공학교육학회(구 한국공학교육기술학회) 2012 공학교육동향 Vol.19 No.6

Cellular NAD+ Level: A Key Determinant of Mitochondrial Quality and Health

황은성,황성윤 대한노인병학회 2017 Annals of geriatric medicine and research Vol.21 No.4

The quality of mitochondria is a key determinant of mitochondrial ATP production and reactive oxygen species generation; therefore, it plays critical roles in energy homeostasis and cellular health. Mitochondrial quality is governed by mitochondrial turnover, which involves autophagic removal of old mitochondria and biogenesis of new ones. Both activities are critically modulated by sirtuin proteins, in particular, SIRT1 and SIRT3. These proteins activate mitophagy and mitochondrial biogenesis through deacetylation-mediated activation of factors participating in key steps of autophagy and mitochondrial protein expression. They also control other factors involved in maintenance of mitochondrial integrity and in damage prevention. At the same time, the activities and protein levels of SIRT1 and SIRT3 decline during aging, contributing to mitochondrial dysfunction associated with tissue aging and many degenerative diseases. However, recent studies suggest that the activity of the sirtuin proteins can be elevated through modulation of nicotinamide adenine dinucleotide (NAD+) and in physiological settings. An understanding of the underlying molecular pathways is actively sought and practical strategies are proposed based on basic research; nevertheless, their applicability at the clinical and subclinical levels could be better recognized and understood in the field of medicine. To this end, this review discusses the recent understanding of the biochemistry underlying the NAD+-redox mediated modulation of cellular sirtuin activity.

Increased citation of Korean scholarly journals during the years 2008 to 2013

황은성 한국과학학술지편집인협의회 2016 Science Editing Vol.3 No.1

Korean academic journals are registered in Korea Citation Index, a government-operated journal indexing system. There has been a constant increase in registry, but whether this change accompanies an increase in quality of the journals has not been determined. In this study, by using the index data of Korea Citation Index, status of journal citation in eight different research fields during the years 2008 to 2013 was analyzed. Impact factors of top 50% journals and the number of the journals with high impact factor increased in all the fields, while the number of journals with low impact factor decreased. The change varied in degree among the different fields, and that in social science and medicine was most positive. These changes appear not to be caused by an increase in self citation, although self citation itself is quite high. International citation of the journals also substantially increased in the fields of science, technology, and medicine. These results indicate a genuine increase in the quality of papers and an improvement in citability of the journals published in Korea. This positive change could be attributed to several factors that include the quality of the information in the papers and the environments that encourage the citation of domestic journals.

Impaired Autophagic Flux in Glucose-Deprived Cells: An Outcome of Lysosomal Acidification Failure Exacerbated by Mitophagy Dysfunction

황은성,송선범 한국분자세포생물학회 2023 Molecules and cells Vol.46 No.11

Autophagy dysfunction is associated with human diseases and conditions including neurodegenerative diseases, metabolic issues, and chronic infections. Additionally, the decline in autophagic activity contributes to tissue and organ dysfunction and aging-related diseases. Several factors, such as down-regulation of autophagy components and activators, oxidative damage, microinflammation, and impaired autophagy flux, are linked to autophagy decline. An autophagy flux impairment (AFI) has been implicated in neurological disorders and in certain other pathological conditions. Here, to enhance our understanding of AFI, we conducted a comprehensive literature review of findings derived from two well-studied cellular stress models: glucose deprivation and replicative senescence. Glucose deprivation is a condition in which cells heavily rely on oxidative phosphorylation for ATP generation. Autophagy is activated, but its flux is hindered at the autolysis step, primarily due to an impairment of lysosomal acidity. Cells undergoing replicative senescence also experience AFI, which is also known to be caused by lysosomal acidity failure. Both glucose deprivation and replicative senescence elevate levels of reactive oxygen species (ROS), affecting lysosomal acidification. Mitochondrial alterations play a crucial role in elevating ROS generation and reducing lysosomal acidity, highlighting their association with autophagy dysfunction and disease conditions. This paper delves into the underlying molecular and cellular pathways of AFI in glucose-deprived cells, providing insights into potential strategies for managing AFI that is driven by lysosomal acidity failure. Furthermore, the investigation on the roles of mitochondrial dysfunction sheds light on the potential effectiveness of modulating mitochondrial function to overcome AFI, offering new possibilities for therapeutic interventions.

학술지의 국제화와 연구부정

황은성 한국공학교육학회 2012 Ingenium(人材니움) Vol.19 No.6

시뮬레이션과 계층분석법을 이용한 군 자동화 물류센터 최적 설계에 관한 연구

황은성(Hwang, Eun-Seong),백승원(Baik, Seung-Won) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.2

우리 군은 21세기 군수환경에 적합한 물류 운용체계 발전을 위해 아직 대다수를 차지하는 기존 재래식 물류 설비를 교체하는 현대화 사업을 활발하게 진행 중이며 향후 각급제대로까지 더욱 확대시켜나갈 계획이다. 본 연구에 서는 군 물류 프로세스의 중심이 되는 자동화 물류센터를 시뮬레이션하여 현재의 시스템을 분석하고 나아가 최적대 안을 설계하는데 효과적인 의사결정 과정을 제시할 목적으로 수행되었다. 특히 물류센터의 자동화 사업이 활발히 추 진되는 것과 이러한 물류센터의 특성상 다양한 설계안과 평가기준이 필요하다는 것에 착안하여 동일규모의 대안을 추가 구성하였다. 총 48개의 대안 중에서, 기존 연구를 바탕으로 몇 가지 고려할만한 대안들을 정의하고 시뮬레이션 과 AHP를 활용하여 최적의 설계안을 도출하였다. 의사결정권자의 경험과 능력이 어느 조직보다 가장 큰 비중을 차지 하는 현행 군 물류체계에서 합리적인 최적대안을 선정하는데 큰 도움이 되도록 하였다. 본 연구에 제시된 이러한 방 법은 방대한 국방예산이 투입되는 군 물류센터 현대화 사업에 있어 경제적인 비용의 절감과, 현재와 미래의 물류센터 에 대한 진단과 평가가 가능하게 하여 향후 국방 군수 현대화 사업추진에 큰 기여를 할 것으로 기대한다. Modernization projects are actively underway to replace conventional logistics equipment for the development of the 21st century logistics management system. The modernized logistics system is expected to expand to each troops on future. In this paper, we deal with simulation of automated logistics center to analyse the current system. Especially, the alternative to the same scale is designed based on needs of military distinctiveness. As a result, it can be effectively compared the current system. The result obtained in this design process is comprehensively analyzed by the AHP(Analytic Hierarchy Process). The proposed method in this study is allowed to cost-effectively evaluate current and future automated logistics center. And, that is expected to contribute to modernization projects of the military logistics system.

비상 알림과 조명 기능을 갖춘 스마트 도어락 개발

황은성(E. S. Hwang),배준선(J. S. Bae),김기선(K. S. Kim),최운식(U. S. Choi),김성일(S. I. Kim) 한국생산제조학회 2017 한국생산제조시스템학회 학술발표대회 논문집 Vol.2017 No.4