FK506이 T 림프구 사멸에서 활성산소 생성에 미치는 영향

이호균(Ho Kyun Lee),정상영(Sang Young Chung),최수진나(Soo Jin Na Choi) 대한외과학회 2009 Annals of Surgical Treatment and Research(ASRT) Vol.77 No.5

Purpose: Tacrolimus (FK506) has been widely used as an immunosuppressant in organ transplanted recipients to suppress organ rejection phenomenon. We investigated the role of oxidative stress and heme oxygense-1 by FK506 on human Jurkat T cells. Methods: The cells viability was examined by DAPI stain, enzyme activity of caspase family proteins, and western blotting for Baks, PUMA, iNOS, HO-1. Cells were cultured in the absence or presence of CoPPIX or ZnPPIX and the fluorescence intensity was analyzed using a flow cytometry. Results: Treatment with FK506 increased the generation of reactive oxygen species (ROS), including hydrogen peroxide and superoxide anion, and NO in Jurkat cells in a dose-dependent manner. Immunohistochemistry and Western blot analysis data revealed the hemoxygenase-1 (HO-1) was induced by the addition of FK506 in Jurkat cells. Induction of CoPP, HO-1 inducer, resulted in decreased intracellular H₂O₂ and NO concentrations. Instead ZnPP, an HO-1 competitive inhibitor did it reversely. In addition, ZnPP regulates iNOS protein synthesis by inhibition of HO-1. Conclusion: Increase of HO-1 expression would induce to decrease the intracellular H₂O₂ and NO concentrations. Also, HO-1 would regulate iNOS protein synthesis. Consequently, we can expect the regulation of HO-1 expression with concomitants use of FK506 to suppress organ rejection phenomenon by enhancing apoptosis.

Mycophenolic Acid에 의해 유도된 Jurkat 세포주 세포자멸사에서 Heme Oxygenase-1의 발현이 미치는 영향

이호균(Ho Kyun Lee),최수진나(Soo Jin Na Choi) 대한외과학회 2010 Annals of Surgical Treatment and Research(ASRT) Vol.78 No.6

Purpose: This study demonstrates that pharmacologic induction of heme oygenase-1 (HO-1) along with catalytic activation significantly modulated apoptosis of Jurkat cells induced by mycophenolic acid (MPA). Methods: Cells were cultured with the presence or absence of MPA. Flow cytometric analysis was performed after propidium iodide staining. Western blotting of HO-1, Bcl, and Bax was also performed. Cells were stained 4’-6-Diamidino-2-phenylindole (DAPI) and measured by flow cytometry in the absence or presence of CoPPIX. Results: Treatment of MPA decreased cell viability in a dose- and time-dependent manner. MPA-induced cell death was confirmed as apoptosis characterized by sub G0/G1 phase arrest. Expression of HO-1 assumes a pattern of decline after rising at the initial phase. CoPPIX, HO-1 inducer, significantly inhibited the cisplatin-induced apoptosis. Treatment of MPA resulted in reactive oxygen species (ROS) generation in Jurkat cells. CoPPIX attenuated ROS production in MPA-treated cells. Conclusion: This result suggests that the protective mechanism of HO-1 on MPA-induced cytotoxicity is associated with direct inhibition of ROS generation and mitochondrial permeability transition.

도서산림 관리를 위한 관련 법제도 고찰과 개선방안에 관한 연구

이호상 ( Lee¸ Ho-sang ),현창석 ( Hyun¸ Chang-seok ),이보라 ( Lee¸ Bo-ra ),이광수 ( Lee¸ Kwang-soo ),신순호 ( Shin¸ Soon-ho ) 한국도서(섬)학회 2021 韓國島嶼硏究 Vol.33 No.2

본 연구는 도서지역 산림 관리를 위해 현행 법·제도에 관한 고찰을 통하여 지속적인 도서지역의 산림 생태계 보전을 위한 도서산림관리 방향을 제시하는데 있다. 최근 국내외적으로 도서 생물다양성 보전 등에 대한 논의가 증가하고 있으며, 우리나라 도서(섬) 관리정책도 주민의 삶, 경제, 생태적 지속성 등을 고려하는 방향으로 변화되고 있다. 우라나라의 도서는 각 부처에 따라 그 수치가 상이하나 최근의 발간한 관련 서적과 행정안전부 및 해양수산부 발표에 따르면 2020년 4월 기준으로 총 3,383개(유인도서 465개, 무인도서 2,918개)로 파악되었으며, 산림의 분포하는 도서는 2,325개(69.5%)로 산림면적은 총 220,819㏊로 전국 산림면적의 약 3.5%를 차지하고 있다. 도서지역 관련하여 유인도서는 행정안전부와 국토교통부, 무인도서는 해양수산부, 특수도서는 환경부와 해양수산부 그리고 행정안전부가 법적 근거를 가지고 관리함으로써 도서 관리주체가 다원화 되어 있고, 주로 유인도서는 개발, 무인도서 및 특수도서는 보전적인 특징을 가지고 있다. 산림분야는 산림보호를 직접적인 대상으로 하는 「산림보호법」이 있고 그 밖에「자연환경보전법」 등과 같이 환경보전이나 생태계보전과 관련하여 산림을 간접적으로 보호하는 법체계를 가지고 있다. 도서지역에는 여타지역과 기후나 자연 생태적 환경이 다르고, 오랫동안 육지부와 격절되어 있는 삶의 여건에 의해 산림자원적 측면에서 독특한 특성을 가지고 있다. 그러나 이러한 산림자원은 근래 개발행위와 생태계 자체의 교란 등으로 인해 여러 가지 부정적 변화가 야기되고 있다. 도서지역의 산림보호는 섬 자체의 가치를 제고해 줄 뿐만 아니라 독특한 산림자원의 안정적 보호라는 측면에서 매우 중요하다. 본 논문에서는 이 같은 도서산림을 보호하는데 궁극적 목적을 두고 그 제도적 개선방안을 모색하고자 한다. 도서산림 관리를 위한 법제의 개선안으로 첫째, 현행 법령 등을 개정하는 방안과 ‘(가칭)도서지역 산림보전 및 관리에 관한 법률’을 제정하는 방안을 제시하고자 한다. 현행 법률 등의 개정(안)은 도서지역 산림관리 위주로 산림자원조성과 산림보호 및 예산을 강화하기 위한 규정만을 개정하는 안으로 가장 용이한 개선방안이라고 할 수 있다. ‘(가칭)도서지역 산림 보전 및 관리에 관한 법률’을 제정하는 방안은 도서산림 관리의 권한을 보다 명확하게 하여 부처간 충돌문제가 발생하지 않을 수 있다. 이를 통해 도서지역 산림관리의 실효성을 확보하고, 산림청이 도서지역에서도 산림의 체계적인 관리에 대한 책임을 지는 당위성을 확보할 수 있을 것이다. This study was undertaken to suggest the direction of island forest management for the conservation of the forest ecosystem in the island region through the review of the current legal system for forest management in the island area. Recently, there has been an increasing discussion on the conservation of island biodiversity both domestically and internationally, and the island management policy in Korea has also been changed to consider the life, economy, and ecological sustainability of local residents. The total number of islands that are geographically cut off from land and surrounded by the sea was 3,383(465 inhabited islands and 2,918 uninhabited islands), 2,325 (55.9%) distributed forests and 220,819ha forest area, which is estimated to account for about 3.5% of the nation's forest area. In relation to the island area, the principal agents in island management are diversified by managing the populated islands via the Ministry of the Interior and Safety, the uninhabited islands with the Ministry of Oceans and Fisheries, the Ministry of Environment, the Ministry of Oceans and Fisheries, and the Ministry of the Interior and Safety. Mainly, inhabited islands are developed while uninhabited islands and special islands have conservation characteristics. In the forest sector, other than the Forest Protection Act, which is directly subject to forest protection, forests are indirectly protected in connection with environmental conservation or ecosystem conservation, including by the Natural Environmental Conservation Act. The legal system that approaches the concept of island forest as a different concept rather than that of a collective is needed, as most of the current forest-related laws are applied to develop, use, preserve, and manage forests and mountainous areas. As a measure to improve the legal system for the management of island forests, first, it is intended to suggest a plan to revise the current laws and regulations and to enact the Act on the Conservation and Management of Forests on Islands (tentative name). The revision (proposal) of the current law is the easiest improvement plan by revising only the regulations to create forest resources, protect forests, and strengthen budgets, mainly for forest management in the island areas. The plan to enact the Act on the Conservation and Management of Forests in Island Areas (tentative name) may make the authority of the management of island forests clearer, so that no conflict between ministries may occur. Through this, it will be possible to secure the effectiveness of island forest management and to secure the necessity of the Forest Service to take responsibility for the systematic management of forests in the island areas.

임펠러 슈라우드 면의 형상 변화에 따른 다익팬 성능

이호호(Ho Ho Lee),최항철(Hang Cheol Choi),이원석(Won Suk Lee),정재구(Jae Goo Jung),이윤표(Yoon Pyo Lee),김광호(Kwang Ho Kim),정진택(Jin Taek Chung) 한국유체기계학회 2010 유체기계 연구개발 발표회 논문집 Vol.2010 No.12

허브 형상에 따른 정풍량 환기팬의 유동과 성능특성

이호호(Ho Ho Lee),최항철(Hang Cheol Choi),정재구(Jae Goo Jung),이윤표(Yoon Pyo Lee),신유환(Yoohwan Shin),정진택(Jin Taek Chung) 한국유체기계학회 2012 한국유체기계학회 논문집 Vol.15 No.2

수술후 7년에 재발한 췌장의 고형 유두상 상피종양

이호심(Ho Sim Lee),이성걸(Seong Geol Lee),이정선(Jeong Sun Lee),최창환(Chang Whan Choi),김용기(Young Ki Kim),김종숙(Jong Sook Kim),우제호(Je Ho Woo) 대한소화기학회 1991 대한소화기학회지 Vol.23 No.4

Solid and papillary epithelial tumor that occurs chiefly in young woman. It is amenable to surgical resection and cure. Recurrence after operation and distant metastasis are rare. But, a few cases with recurrence or distant metastasis have been reported. We have encounted a case of solid and papillary tumor of the pancreas with distant metastasis and recurrence 7 years after resection in 34 years old female, so report it.

국소배기시설의 덕트피팅 압력손실계수 예측

이호형 ( Ho Hyung Lee ),이승철 ( Seung Chul Lee ),옥윤용 ( Yun Yong Ok ),이승호 ( Seung Ho Lee ) 대한설비관리학회 2014 대한설비관리학회지 Vol.19 No.4

Traditionally, the coefficients have been obtained using experimental measurements according to AHSRAE Standard 120, a process which is time consuming and expensive. An alternative is to use CFD, but this has uncertainty due to the approximations used in modeling turbulence. This study estimated that the pressure loss coefficients of duct fitting(elbow, tee) by turbulence model(Standard k-ε, Realizable k-ε, RSM, SST k-ω) using CFD techniques. The results show that Realizable k-ε model could accurately predict the pressure loss coefficients from all cases.

임신중 발생한 추간판 탈출증

이호형 ( Ho Hyung Lee ),김석영 ( Suk Young Kim ),변아롱 ( A Rong Byun ),오혜영 ( Hea Young Oh ),이현이 ( Hyun Lee Lee ),윤정혜 ( Jung Hye Yoon ),이상구 ( Sang Gu Lee ) 대한주산의학회 2006 Perinatology Vol.17 No.1

A herniated nucleus pulposus (HNP) during pregnancy has been a rare occurrence with a reported incidence of 1:10,000 case. It is hard to diagnose because of the potentially hazardous effect of ionizing radiation to the fetus when complaining back pain during pregnancy. In this case, magnetic resonance imaging (MRI) provide safe and useful modality and in general, back pain usually respond readily to conservative treatment. Cauda equina syndrome or severe and/or progressive neurologic deficit is a medical emergency that necessitates prompt surgery during pregnancy. She admitted at 31 weeks gestation for sudden development of right leg paresthesia and ankle motor weakness, an MRI showing compression on right nerve root at the level of L5~S1. After 4 weeks treated with bed rest and analgesics, we delivered by cesarean section and laminectomy at the same time. We have experienced a pregnancy with HNP, so report of this case with brief review of literature.

다층 CP-DRA의 이득 및 축비대역폭 증대에 관한 연구

이호상(Ho-Sang Lee),조동기(Dong-Ki Jo),정영호(Young-Ho Jung),김철복(Cheol-Bok Kim),손호철(Ho-Cheol Son),이문수(Mun-Soo Lee) 대한전자공학회 2009 電子工學會論文誌-TC (Telecommunications) Vol.46 No.7

본 논문에서는 십자형 슬롯 급전방식을 이용한 다층 CP-DRA(Circularly Polarized Dielectric Resonator Antenna)의 이득 및 축비대역폭 증대에 관하여 연구한다. CP-DRA의 이득 및 축비대역폭 증대를 위하여 단층 CP-DRA에 대하여 분석하고, 이를 바탕으로 다층 CP-DRA의 구조를 제안하여 동작특성을 연구한다. 또한, 안테나의 이득 증대를 위하여 다층 CP-DRA 사이의 간격을 0.7 λ? 및 1.2 λ?로 2×2 평면 배열한 안테나의 방사특성을 CST사의 MWS을 이용하여 시뮬레이션을 통해 검토한다. 제안한 다층 CP-DRA를 제작하여 측정한 결과, 이득 및 대역폭이 단층 CP-DRA에 비하여 약 2배 개선됨을 알 수 있다. 그리고, 다층 CP-DRA를 1.2 λ? 간격으로 배열한 안테나에서 일반적인 배열안테나와 달리 grating lobe가 크게 감소하며, 이득은 13.4㏈i, 축비대역폭은 0.8㎓으로 증가하였다. In this pater, a CP-DRA(Circularly Polarized Dielectric Resonator Antenna) using cross-slot-feed is studied to enhance the gain and axial ratio bandwidth. First, a single layer CP-DRA is studied as a reference for comparison. Then a new type of multilayer CP-DRA is proposed to enhance the gain and axial ratio bandwidth. In consideration of the antenna gain enhancement, the spacing between the elements of the multilayer CP-DRA is examined through analysis of the radiation performance of a 2×2 planar array of DRAs with a spacing of 0.7λ? and 1.2λ? using CST Microwave Studio. The measured result shows that the gain and bandwidth of the multilayer structure is approximately twice that of the single layer one. In the case of the array antenna, in which the spacing between multilayer CP-DRA element is 1.2λ?, a grating lobe is reduced, in contrast to what we can expect from a conventional antenna array. The gain is 13.4d㏈i and axial ratio bandwidth is 0.8㎓.

허브 형상에 따른 정풍량 환기팬의 유동과 성능특성

이호호(Ho Ho Lee),최항철(Hang Cheol Choi),정재구(Jae Goo Jung),이윤표(Yoon Pyo Lee),신유환(Yoo Hwan Shin),정진택(Jin Taek Chung) 한국유체기계학회 2011 유체기계 연구개발 발표회 논문집 Vol.2011 No.11

The constant air volume flow fan can maintain constant flow rate to the wide range of exit pressure. Therefore, the use of this fan is increasing recently for ventilation of high building. Brushless DC motor is adopted to this fan because that has advantages of compactness and performance. But this type of motor protrude from impeller hub side to fan inlet. The Impeller inlet flow is influenced by size of this obstacle called hub. In this paper, the influence of hub shape on the fan performance characteristics are experimentally and numerically analyzed. CFX 12.0 is used to perform the fan internal flow analysis and numerical results are compared with the experiments. Depending on hub shape, internal loss is generated and the performance and efficiency are reduced. The best performance is occurred around h/b1=0.25. The results of this study will be contribute to initial design of constant air volume flow fan development.