Dimethylnitrosamine 유발 급성 간 손상 흰쥐에서 ^(99m)Tc-Lactosylated Serum Albumin을 이용한 간 기능의 평가

정신영,이재태,서명랑,유정아,배진호,안병철,황재석,정재민,하정희,이규보 대한핵의학회 2003 핵의학 분자영상 Vol.37 No.6

목적: ^(99m)Tc-lactosylated serum albumin (^(99m)Tc-LSA)은 간세포에 특이적으로 결합하는 간수용체 영상용 방사성의약품으로 새로이 합성되었다. 간섬유화를 유발하는 dimethylnitrosamine (DMN)을 투여한 간 손상 휜쥐 모델에서 ^(99m)Tc-LSa의 역동학적인 간섭취를 조사하고 간효소치의 변화와 조직학적 소견을 비교하여, LSA의 간섭취가 간기능의 변화를 반영하는지를 연구하였다. 대상 및 방법: SD계 흰쥐에 DMN를 27 mg/kg으로 복강 내 주사하여 급성 간손상을 유도하고 대조군과 비교하였다. DMN을 주사한 흰쥐를 3일(DMN-3), 8일(DMN-8), 21일(DMN-21)에 ^(99m)Tc=LSA (1,665 mg/kg) 29 MBq를 정맥 주사하여, 30분 동안 동적 영상을 획득하고 간과 신장부위에 관심영역을 설정하여 간과 심장부위의 시간방사능 곡선을 얻었다. 간기능 평가를 위해 시간방사능 곡선을 이용하여 간섭취지수와 혈중제거지수를 구하였고 곡선 최적화를 시행하였다. DMN 투여군과 대조군의 간효소치의 변화와 간조직의 광학현미경 소견을 비교하였다. 결과: 대조군에서는 ^(99m)Tc-LSA가 빠르게 간에 섭취되고 혈중에서 제거되었으나 DMN을 처리한 군에서는 간섭취가 낮았다. 간섭취지수의 비교에서 대조군에 비해 DMN 처리군에서 유의하게 간섭취지수가 낮았다(DMN-3: 0.842, DMN-8: 0.898, DMN-21: 0.91, 대조군: 0.96, p<0.05). 혈중제거지수의 비교에서도 대조군에 비해 DMN 처리군에서 혈중제거지수가 유의하게 높았다(DMN-3: 0.731, DMN-8: 0.654, DMN-21: 0.604, 대조군: 0.473, p<0.05). 비선형 회귀분석에서 R_(2) 값은 0.9이상으로 좋은 일치를 보였고, 대조군에ㅓ K값이 DMN처리군에 비해 크고(DMN-3: 0.28, DMN-8: 0.41, DMN-21: 0.46, 대조군: 0.97, p<0.05), T_(1/2)값은 작았다(DMN-3: 2.5, DMN-8: 1.7, DMN-21: 1.5, 대조군: 0.7, p<0.05). 간효소치의 변화는 DMN-3군에서는 대조군에 비해 상승하였으나 DMN-8, DMN-21군에서는 간효소치의 상승이 관찰되지 않았다. 간조직 소견의 경우 DMN-3군에서 중심정맥 주위에 괴사가 관찰되었으나 DMN-8군, DMN-21군에서는 미약한 정도의 염증세포 침윤만이 관찰되었다. 결론: ^(99m)Tc-LSA 간신티그래피의 간섭취 정도는 간손상과 반비례하였으며 간섭취의 변화는 조직학적 손상이 심한 정도와 간손상후 회복되는 과정을 반영하여 주었다. ^(99m)Tc-LSA 간신티그래피가 간손상을 평가하고 간손상후 회복되는 과정을 추적하는 간수용체 영상용 방사성 의약품으로 사용될 수 있을 것으로 생각된다. Objects: ^(99m)Tc-lactosylated human serum albumin(LSA) is a newly synthesized radiopharmaceutical that binds to asialoglycoprotein receptors, which are specifically presented on the hepatocyte membrane. Hepatic uptake and blood clearance of LSA were evaluated in rat with acute hepatic injury induced by dimethylnitrosamine(DMN) and results were compared with corresponding findings of liver enzyme profile and these of histologic changes. Materials and Methods: DMN (27 mg/kg) was injected intraperitoneally in Sprague-Dawley rat to induce acute hepatic injury. At 3(DMN-3), 8(DMN-8), and 21(DMN-21) days after injection of DMN, LSA injected intravenously, and dynamic images of the liver and heart were recorded for 30 minutes. Time-activity curves of the heart and liver were generated from regions of interest drawn over liver and heart area. Degree of hepatic uptake and blood clearance of LSA were evaluated with visual interpretation and semiquantitative analysis using parameters (receptor index : LHL3 and index of blood clearance : HH3), analysis of time-activity curve was also performed with curve fitting using Prism program. Results: Visual assessment of LSA images revealed decreased hepatic uptake in DMN treated rat, compared to control group. In semiquantitative analysis, LHL3 was significantly lower in DMN treated rat group than control rat group (DMN-3:0.842, DMN-8: 0.898, DMN-21: 0.91, Control: 0.96, p<0.05), whereas HH3 was significantly higher than control rat group (DMN-3: 0.731, DMN-8: 0.654, DMN-21: 0.604, Control: 0.473, p<0.05). AST and ALT were significantly higher in DMN-3 group than those of control group. Centrilobular necrosis and infiltration of inflammatory cells were most prominent in DMN-3 group, and were decreased over time. Conclusion: The degree of hepatic uptake of LSA was inversely correlated with liver transaminase and degree of histologic liver injury in rat with acute hepatic injury.

셀레늄이 메기 간장 및 신장의 카드뮴 축적에 미치는 영향

유일수,문연자,이정호 원광대학교 환경과학연구소 1998 環境科學硏究誌 Vol.7 No.1

항암제 AG60이 흰생쥐 위점막 상피세포의 DNA합성에 미치는 영향 : 자기방사법적연구

박경호,안의태,고정식,하상선,한영복,정영신,홍은경,유보림,김상건,이경영,강종구 대한해부학회 1999 Anatomy & Cell Biology Vol.32 No.1

두개골의 3차원 영상 분석을 위한 전산화단층촬영 방법의 비교 : 상층 두께가 3차원 영상의 계측에 미치는 영향

정호걸,김기덕,박혁,김동욱,정해조,김희중,유선국,김용욱,박창서 대한구강악안면방사선학회 2004 Imaging Science in Dentistry Vol.34 No.3

Purpose : To evaluate the quantitative accuracy of three-dimensional (3D) images by means of comparing distance measurements on the 3D images with direct measurements of dry human skull according to slice thickness and scanning modes. Materials and Mathods : An observer directly measured the distance of 21 line items between 12 orthodontic landmarks on the skull surface using a digital vernier caliper and each was repeated five times. The dry human skull was scanned with a Helical CT with various slice thickness (3, 5, 7 mm) and acquisition modes (Conventional and Helical). The same observer measured corresponding distance of the same items on reconstructed 3D images with the internal program of V-works 4.0 (Cybermed Inc., Seoul, Korea). The quantitative accuracy of distance measurements were statistically evaluated with Wilcoxons’ two-sample test. Results : 11 line items in Conventional 3 mm, 8 in Helical 3mm, 11 in Conventional 5 mm, 10 in Helical 5 mm, 5 in Conventional 7 mm and 9 in Helical 7 mm showed no statistically significant difference. Average difference between direct measurements and measurements on 3D CT images was within 2 mm in 19 line items of Conventional 3 mm, 20 of Helical 3 mm, 15 of Conventional 5 mm, 18 of Helical 5 mm, 11 of Conventional 7mm and 16 of Helical 7 mm. Conclusion : Considering image quality and patient’s exposure time, scanning protocol of Helical 5 mm is recommended for 3D image analysis of the skull in CT.

소아에서 이모장치가 하악골 및 측두하악관절에 미치는 영향에 관한 유한요소법적 분석

유정호,이상호 大韓小兒齒科學會 1993 大韓小兒齒科學會誌 Vol.20 No.1

The purpose od this study was to investigate the stress distribution and displacement in the mandible and temporomandibular joint during application of chin cap. The dry skull of child in mixed edntition was used to make a 2-dimensional finite element model. It was composed of 765 elements and 1321 nodes. An orthopedic forces, 500gm,was applied around the gnathion to condylion(A plane),the second was 20 degrees upward from the first plane(B plane),the third was 50 degrees upward from the first plane(C plane). The results were as follows: 1.When the retraction was applied to A plane,the distribution of tensile stress was greater on the middle and posterior portion of mandiular fossa, apex of condylar head, anterior portion of articular disc, distal portion of first molar, posterior portion of condylar neck and head. Particulary, it was concentrated on condylar head and neck. As the retracion was directed more upward, it was decreased totally and concentrated on the first molar. 2.When the retraction was applied to A plane, Compressive stress concentrated on the sigmoid notch and anterior portion of condylar head and neck. As the retraction was directed more upward, it moved from condylar head and neck toward anterior teeth portion and it was concentrated on second premolar. 3.When the retraction was applied to A plane, displacement was directed to posterior and superior in mandibular anterior body, mandibular posterior body, coronoid process, condylar head,middle and posterior portion of mandibular fossa. But it was directed to posterior and inferior in mandibular angle and ramus, anterior portion of condylar neck, anterior portion of mandiblar fossa. As the retraction was directed more upward, it was directed to posterior and inferior in coronoid process and posterior portion of condylar neck. The posterior movement of mandible was decreased. 4.When the retraction was applied to A plane, the stress of mandibular body and ramus was small and it was distributed on compact bone. As the retraction was directed more upward, the stress was distribeted widely on teeth and permanent teeth germs.

Epstein-Barr 바이러스 형질전환법을 이용한 파상풍 톡소이드에 대한 사람 단세포군 항체의 생산

유승민,조정제,호순태,하윤문 大韓免疫學會 1993 大韓免疫學會誌 Vol.15 No.-

For production of tetanus toxoid(TT) specific human monoclonal antibodies, anti-TT antibody secreting peripheral B lymphocytes were separated by rosetting with TT-coated SRBC. And, B lymphoblastoid cell line(BLCL) was established by Epstein-Barr Virus(EBV) transformation methods. Stable BLCLs were established after three times of cloning by limiting dilution. To establish the maximal antibody producing condition, several environmental factors were tested. The optimal condition for maximum antibody prodiction was 4 day culture of 1 x 105cells/ml concentration in RPMI 1640 complete culture media supplemented with 20% fetal calf serum, and the maximum concentration of secreted antibody was about 900ng/ml. The antibody production of BLCL was decreased during long-term culture after establishment of cell line, but antibody production was maintained by repeated cloning by limiting dilution.

모드스펙트럼해석법에 의한 교량의 내진설계에 관한 연구

유영화,최정호,김운학 안성산업대학교 1995 論文集 Vol.27 No.-

As an importance of seismic design have been increasing, it is necessary to establish an adequate guidelines of which designers can make use for the effective design according to the types of bridges. When applying the codes, seismic design forces are determined by single mode spectral analysis method for the general bridges whose geometric shape is relatively simple, where seismic design forces are obtained only using the fundamental frequency. On the contrary, when the geometeric irregularities such as span length and pier hight are developed, one can expect a substantial errors which could be taken into account in multi-mode spectral analysis. For the determination and comparison of the design forces by mode spectral analysis, the program based on design codes which performs a 3-dimensional dynamic analysis and make it easier for the designers to analyze the reponse displacements of mode shapes by means of the post processor is developed and applied to several example bridges.

성공적인 마을공동사업의 운영특성 분석-충청남도와 충청북도를 중심으로-

정상숙, 윤성수, 장우석, 리신호 忠北大學校 農業科學硏究所 2019 農業科學硏究 Vol.35 No.2

본문참고

유한요소법에 의한 용접잔류응력의 해석

김정호,조성욱,유봉준 중앙대학교 생산공학연구소 1999 생산공학연구소 논문집 Vol.8 No.1

대형구조물의 용접시 잔류변형과 잔류응력은 구 구조물의 모양과 크기, 그리고 구속조건에 따라 크게 달라진다. 따라서, 대형구조물의 잔류응력에 대한 정확한 해석을 위해 용접 잔류응력 및 용접 잔류변형을 정확히 예측할 수 있는 적절한 유한요소해석 절차의구현이 필요하다. 본 연구에서는 용접 잔류응력과 변형률의 존재를 예측할 수 있는 열전달 해석 및 열탄소성 해석과 같은 적절한 유한요소해석 과정을 찾고자 한다. 해석을 위해 아크의 열원에 대한 가우시안 분포를 가정하고 용접부의 상변화에 대한 엔탈피모델을 선정한다. 그리고, 대형구조물의 열전달해석을 위해 Remeshing기법을 이용한 유한요소모델의 생성이 필요하다. 끝으로, 개발된 해석과정은 단순맞대기 용접에 대해 적용해 보았고, Remeshing 기법은 컴퓨터 자원에 대한 절약 측면에서 상당한 효과를 나타내었다. Welded structures experience changes in shape, size and constraint conditions after favirication due to internal residual stresses. For the accurate simulation of the typical welding procedure, transient heat transfer analysis as well as thermal-elasti-plastec analysis should be employed. In this paper, appropriate finite element analysis procedures that can predict welding residual stresses and strains are presented. Gaussian distribution of arc heat source is assumed andenthalpy model is employed for phase change of the welding zone. Finally for the purpose of applying the developed technique to large scale structrues, remeshing techniques by successive generation of finite element model are given for that transfer analysis. The developed analysis procedure are tested for the simple butt welding which gives reliable results. Remeshing techniques are also tested against the existing mesh pattern which showed considerable reduction in computational resources.

인공 산성비 용액 함침 및 경사평면법에 의한 옥외용 실리콘 고무의 열화 특성 평가

김정호,정규원,유영식,양계준,박용관 成均館大學校 科學技術硏究所 1999 論文集 Vol.50 No.1

We investigated the effect of acid rain on the surface aging, and resistance to tracking and erosion of silicone rubber materials : First, we measured the contact angle, SEM, EDX, and weight reduction to investigate the surface aging caused by immersion in the artificial acid rain solution. From the results of a series of experiments, we concluded that the acid rain attacked the base polymer of the surface, and lead to the depolymerization. Second, we adopted Inclined-Plane Method to measure the resistance to tracking and erosion of silicone rubber, and rather not observably affected the immersed specimen in the tracking resistance than in the erosion resistance.