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      • 독성물질의 세포사 기전 및 세포사 유발물질의 검색법 개발에 관한 연구(Ⅰ) : 독성물질로 인한 파킨슨병 모델에서의 세포사 기전 연구 Study on the cell-death mechanisms of toxin-induced parkinsonism

        강태석,김종민,서경원,김영옥,김준규,오재호,이윤동,김규봉,오정자,송연정,임종준,전범석,문전옥,최광식 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

        MPTP 독성물질이 도파민성 신경세포에 선택적으로 작용하여 산화성 손상에 의한 신경세포사를 일으키는 것을 이용하여 파킨슨병의 동물모델을 만들고, 이를 통해서 아폼토시스를 비롯한 포사의 기전에 대한 연구 및 너코틴의 신경세포 보호효과 여부를 판정하는 실험을 병행하고자 하였다. 파킨슨꾐의 동물모델을 MPTf 독성 물질을 이용하여 확립하였으며, MPTP(30mgag, i.p.)를 투여한 후 1, 2,3, 4, 5일째 흑질 조직을 채춰하여 tarm로 박걸하여 tyrosine hydroxylase 면역조직화학염색을 수행하여 cell countif우한 결과, control은 57.635ce11s, 1일째 친.OfDells,2일째 57.9±6cells,3일릴 없.3±죠ells, 4일째 49.0츠3cells, 5일째 39.4±Scells료 4, 3일째 뚜렷한 신경세포 수의 감소를 보였다. 신경세포사 기전 규명을 위한 아폼토시스 분걱에서는 벼PTP 투여 후 1, 2, 3, 4, 5일째 조직을 채취하여 Hoechst staining, TUNEL staining을 수곡하였는데 양성 반응을 보인 신경세포는 관찰되지 않아. 아폼토시스로 인한 세포사가 관찰되지 않았다. bIPTP 파킨슨병 동물모델에서 nicotine 보호효과 탐색에 관한 실험은 nicat푸e 0.2mgAg을 5일 퐁안 투여 후 리『fP(30mgag)를 CS7Bt/6 마은스에 복강 내주사로 nicotine과 병용 투여한 후 1, 2, 3, 4, 5일째 뇌를 적출하땄다. 신경세포사가 뚜렷이 관찰되기 시작하는 4, 5일째의 신경세포 수의 감소 정도를 20. 30% 정도 약화시키는 경향을 보였으나, nicotine 보호효과에 대한 추가 실헝이 현재 수행 중에 있다. The cause of Parkinson's disease (PD) is largely unknown. However, free radical toxicit? may plaf a role ip. the degeneration of substantia nigra, which is the Hajorfocus of pathological damages in PD. Recently, a neuroprotective effect of nicotine in PD has been suggested. Therefore, the mechanism of neurodegenerafion and protective potential o( nicotine in PD were investigated in the experimental modeB of Pll using a neurotoxin, C57BL/6mice were administered with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg,j.p.). The degree of neurodegenerafion was determined by immunohistochemical stainiHB oftyrosine hydroxylase (TH). TH-positive cells on nigral sections were found 56.0 ±4, 57.9 ±6,52.315ce11s, 49.0±3cells, and 39,4±Scells at days 1, 2, 3, 4, 5, respectively (controls : 57.6±Scells). Hoechst and TUNEL staining showed no evidence of apoptosis. The exandnation on themice co-adrunistered with nicotine(0.2mgAg) and MPTP(30mgag) revealed a tendency ofnicotine protective effects. At days 4 and 5, the degree of TH-positive cells was decreased by20-30%, In corclusiffn, the role of apoptosis was not evidenced in this MPTP modeB of PB.The possible proteccon by nicotine should be elucidated with further studies.

      • Gymnema산이 췌장도의 Beta-세포에 미치는 영향

        강주섭,서대규,김수조 한양대학교 의과대학 1991 한양의대 학술지 Vol.11 No.2

        The present study was undertaken to investigate the effect of gymnemic acid(GA) on the ultrastructure as well as cellularity of β-cell in the pancreas of rats(N=12). Also studied was the effect of GA on the serum insulin and blood glucose levels during intravenous glucose tolerance test(IVGTT) in man(N=10). Healty adult male rats(Wistar strain) weighing around 200 gm were divided into the three groups; the control, 500mg-GA, and 800mg-GA groups. GA was administered orally 3 times daily for 14 days. All experimental animals were given food and water ad labitum and were sacrificed at 15th day after the administeration of GA and starved for 24 hours before sacrificing them. The specimens obtained from the pancreatic tissues were fixed in 10% neutral formalin for 18 hours at 4℃. After embedding in paraffin, the specimens were sectioned with microtome to a theckness of 6mm. For observing the cellularity of β-cell in the pancreatic islets, Gomori's stain was performed. For studying the ultradtructural changes in pancreatic β-cell, pancreas specimens of 1m㎥ size were prefixed in 2.0% glutaraldehyde-2.5% parpformaldehyde phosphate buffer solution(pH7.2) and post-fixed in the 1% osmic acid. After specimens were dehydrated and embedded in the Epon 802, sectioned by ultramicrotome(HT-2, Sorvall Porter-Blum, USA) to a thickness of 600Å, and stained with uranyl acetate and lead citrate by double contrast method. And these preparations were observed with electron microscope (Hitachi H-600). In IVGTT with or without oral GA(15mg), the subjects were fasted for 12 hours before glucose loading(20ml of 25% glucose solution). The blood glucose and serum insulin level were determined respectively by Glucoscot GT-4301 and EIA(enzyme immunoassay)-insulin kit "Insulotek Mochida" before and at 30, 60, 90 and 120 minutes after glucose loading. The results obtained were as follows: 1. In GA(500 mg/kg & 800 mg/kg) treated rats, the cellularity of β-cell throught the pancreatic islets were markedly increased. 2. The insulin secretoty granuled with or without dense core increased in the 500mg-GA group, and the similar changes were obtained in the 800mg-GA group. 3. Following glucose loading, blood sugar level of normal subject elevated from 80.7±2.7 mg/dl to 163.2±15.9mg/dl in 60min. On the other hand, blood glucose level increased from 78.0±2.9mg/dl to 152.1±10.7mg/dl in 30 min after simultaneous administration of glucose and GA. 4. In the IVGTT the serum insulin concentration rose from the basal level of 7.1±1.4 mU/ml to 74.8 15.5 mU/ml while it elevated from 7.4±1.4mU/ml to maximal level of 113.9±33.1 mU/ml in the IVGATT with oral GA. Consequently, it is suggested that gymnemic acid has the direct simulatory effects on the insulin production and secretion of the pancreatci β-cell, and therfore it may be useful for the therapy or prevention of diabetes mellitus.

      • KCI등재

        Fabrication and High-Temperature Compressive Behavior of Unique Multi-Sheet Stacked Block Ni–Cr–Al Metallic Foam

        Kyu‑Sik Kim,Tae‑Hoon Kang,박만호,Kee‑Ahn Lee 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

        Large unique block Ni–Cr–Al superalloy foam was fabricated using a combination method of powder-alloying, multi-sheetstacking, and hot compression processes. Subsequently, the compressive properties and deformation behaviors of multi-sheetstacked block metallic foam were investigated from room temperature to 1073 K. The analysis of the resulting structuralcharacteristics of the block foam showed that the interfaces between the sheets have complex strut interactions, such ascontacted (deformed) and intersected struts. The relative density was measured as 2.93% for sheet foam and 4.90% for blockfoam. The compressive deformation of sheet and block Ni–Cr–Al foams showed the typical compressive stress–strain curvesof plastically deformable metallic foams regardless of foam type. However, different deformation behaviors in the plateauregions were detected based on the type of foam. It is noteworthy that the yield strength of block foam showed a relativelylower value than that of sheet foam, even though the block foam had higher relative density. The existence of unique interfacesin the multi-sheet stacked block foam may have affected strength and plastic deformation. Finally, distinct compressivebehaviors related to the structural and microstructural characteristics of block Ni–Cr–Al foam are discussed.

      • Cd_xZn_(1-x)Te 단결정을 이용한 초고속 THz 전자파의 emitter 특성연구 (Ⅲ)

        강현식,정길환,김태규,이해익 전북대학교 과학교육연구소 2002 과학과 과학교육 논문지 Vol.27 No.-

        Cd_xZn_1-xTe single crystal system is most ideal crystal for ultrawere investigated for ultrafast T-ray emitters, with composition ratio x=0.00, 0.05, 0.10, 0.15, 0.20, and 0.25. We have found that Cd_0.05Zn_0.95Te crystals are best emitters for T-ray generation, also for above all composition ratio x=0.05 crystals, T-ray emitting ability depended on resitivity were investigated. The results is that the crystals greater than 100Ω-㎝ are good emitters. We study on the Azumuthal angle dependence of the (110) plane and could be explane the 3fold symmetric variation of signals. Finally we could show the linearity is above the 10^5.

      • KCI등재
      • 복막유착의 원인 규명과 예방을 위한 실험적 연구

        강대영,송규상,노승무,조준식,이태용 충남대학교 의과대학 지역사회의학연구소 1999 충남의대잡지 Vol.26 No.1

        Postoperative peritoneal adhesion is the most common cause of intestinal obstruction, and intestinal obstruction is one of the most difficult problems in abdominal surgery. In this experimental study for developing peritoneal adhesion model and its prevention, we divided rats into 5 groups; the talc powder treated group, the cotton-fluff treated group, the talc+fluff treated group, the ischemia group and the control group. There were 16 rats in each group. We made incisions on the midabdomen of the rats and administered talc powder, cotton fluff and talc powder+fluff into the peritoneal cavity respectively. In the ischemia group, we clamped the root of superior mesenteric artery for two minutes to induce ischemia on the small bowel of the rat. We counted the number of the peritoneal adhesive sites in peritoneal cavity on the 7th, 14th , 21st and 42nd postoperative day after peritoneal adhesion induced operation, and observed the characters of the adhesion state. The average number of the peritoneal adhesions were 1.25 per one rat in the talc powder group, 1.44 in the fluff group, 1.31 in the talc+fluff group and 1.31 in the ischemia group compared with 0.94 per one rat in the control group performed sham operation. 91.6% of the all adhesions were observed on the peritoneum of the previous incision sites and only 8.4% of the adhesions were adhered to the peritoneal surface of non-incision sites. The data of this study suggest that peritoneal injury and inflammatory reaction is the major cause of peritoneal adhesion. Also this study indicates that foreign bodies can develop peritoneal adhesion, but the effect is much lower than that of peritoneal injury with inflammatoty reaction.

      • 水晶體 β-Crystallin의 Carboxylmethylation에 關한 硏究

        李康一,郭相太,林圭 충남대학교 의과대학 지역사회의학연구소 1988 충남의대잡지 Vol.15 No.2

        Changes of protein patterns of nonmethylated and endogenous or exogenous methylated β-crystallin fractions have been investigated, and then the methyl-acceptor proteins identified by urea /polyacrylamide gel electrophoresis. 1. Nonmethylated β_H and β_L-crystallin were separated in ten, eleven fractions, respectively. In the endogenous methylated β_H-crystallin, subfraction No. 10 was disappeared and No.3 was increased when compared with that of nonmethylated. In the β_L-cryallin, subfraction No.8, 10, 11 were decreased and No.6, 7 was increased. 2. When native β-crystallins were electrophoresed, subfraction No. 7, 9 disappeared and No.8b, 10b were newly appeared and. No. 6 was increased in methylated β_H-crystallin, and subfraction No. 11 was disappeared, No.9 was decreased and No.8 was increased in meth ylated β_L-crystallin. But, subfraction profile of methylted a-crystallin was not changed. 3. Methyl-acceptor proteins in each crystallin were subfraction No. 1, 6, 8 in a-crystallin, 2, 3, 6, l0a in β_H-crystallin and 1, 6, 7, 8, 10 in β_L-crystallin, respectively. These results suggest that the effect of carboxylmethylation on the aggregation of β-crystallin is related to not only the interaction of a, r-crystallin subfractions, but also the interaction of β-crystallin subfractions. On the other hand, a-crystallin is only related to the interaction of the other crystallin subfractions.

      • KCI등재

        동일하지 않는 병렬기계 시스템에서 지연작업수를 최소화하는 Tabu Search 방법

        전태웅,강맹규 한국경영과학회 1995 經營 科學 Vol.12 No.3

        This paper presents a Tabu Search method to minimize a number of tardy jobs in the nonidentical parallel machine scheduling. The Tabu Search method employs a restricted neighborhood for the reduction of computation time. In this paper, we use two different types of method for a single machine scheduling. One is Moore's algorithm and the other is insertion method. We discuss computational experiments on more than 1000 test problems.

      • KCI등재

        저식염 속성 멸치 발효액화를 가공에 관한 연구(Ⅱ) : 숙성 중 oligopeptide 아미노산 함량변화 Changes in the Amino Acids from Oligopeptides during Fermentation

        박춘규,강태중,조규옥 한국식생활문화학회 2002 韓國食生活文化學會誌 Vol.17 No.4

        In order to establish the processing conditions for salt-fermented liquefaction of anchovy(Engrulis japonica), changes in the amino acid composition form oligopeptides during fermentation periods were analyzed. Experimental sample A: chopped whole anchovy, adding 20% water, heating at 50℃ for 9 hrs and then adding 10% NaCl. Sample B: chopped whole anchovy, adding 20% water, heating at 50℃ for 9hrs and then adding 13% NaCl. Sample C: chopped whole anchovy adding 13% NaCl. Sample D: whole anchovy adding 17% NaCl. The total amino acids from oligopeptides in fermented liquefaction of anchovy increased in early fermentation period and reached highest level, and then declined irregularly during fermentation. Their maximum amounts were just after heating at 50℃ for 9 hrs in sample A, after 15 days in sample B, and after 60 days in samples C and D. The fermented liquefaction of anchovy extracts were rich in glutamic acid, aspartic acid, proline, glycine, alanine, lysine and valine. However, the contents of most amino acids fluctuated by the experimental specimens and fermenting periods. Among them glutamic acid was the most abundant amino acid which was occupied 0.6~27.7%(average 24.0%) in the content of total amino acids from oligopeptides. The contribution of the amino acid composition from oligopeptides to extractive nitrogen was occupying average 20.8 and 17.5% in rapid- and low salt-fermented liquefation(sample A,B and C) and traditional fermented liquefaction(sample D), respectively.

      • 디지탈 影像處理를 爲한 畵像表示 시스템에 關한 硏究

        박규태,박명구,신태민,강현철 연세대학교 산업기술연구소 1983 논문집 Vol.15 No.2

        A digital image display system is studied. A TV set is used for a display unit. The system is designed to display 256x212 pixels in a frame and 8 bit gray levels. A microcomputer system is utilized for the image processing which has a Z-80A cpu and s-100 bus. A image processing system which includes a refresh memory system is designed. Images taken by the input system are processed. The image sharpening techniques are introduced. The image edges are found and sharpend using Robert cross operator of spatial differentiation technique. The images are also processed to eliminate noise utilizing the neighbourhood averaging method.

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