파킨슨 증후군을 동반한 조발형 알쯔하이머병 1예

최은정,방현,임주혁,이재홍 대한치매학회 2002 Dementia and Neurocognitive Disorders Vol.1 No.1

Extrapyramidal signs (EPSs) frequently accompany Alzheimer's disease(AD). However, the pathogenesis or pathologic basis for the EPSs in AD remains unclear. We report a case of presenile onset progressive dementia later associated with hemiparkinsonism. Brain biopsy showed neurofibrillary tangles and amyloid plaques. compatible with Alzheimer's disease. There are a few report about dopamine transporter imaging of AD with EPSs. 1-123 IPT SPECT revealed a decreased uptake in both basal ganglia, more severe on the left side and in the caudal putamen, which is consistent with the finding of idiopathic Parkinson's disease. Alzheimer's disease and Parkinson's disease are thought to be coexistent in our patient.

석이중 오르시놀 정량 및 급성독

최혁재,김남재,김동현 경희대학교 동서의학연구소 2001 東西醫學硏究所 論文集 Vol.2001 No.-

In previous study, Gyrophora esculenta showed significant inhibitory effect on α-glucosidases in vitro and blood glucose elevation in vivo In the isolating process of active substance, orcinol was separated from Gyrophora esculenta. Orcinol is known to be toxic, therefore, in this study, it was analyzed by the TLC densitometry method for quantitative determination from Gyrophora esculenta. The average amount of orcinol of Gyrophora esculenta was 0.2%. For the purpose of removing orcinol, the water extract of Gyrophora esculenta was sequentially fractionated by organic solvents, and the acute toxicity of each fraction was assessed in mice. Among them, the LD50 of butanol fraction was 1.19 g/kg(p.o.) and the weight increase of mice in that group was somewhat retarded.

석이에서 분리한 GE974의 α-Glucosidase 저해효과

최혁재,김남재,김동현 경희대학교 동서의학연구소 2001 東西醫學硏究所 論文集 Vol.2000 No.-

This study was conducted to search for the α-glucosidase inhibitor from the natural products. In the previous study, the water extract of Gyrophora esculenta exhibited a potent inhibitory effect on α-glucosidase activities. Then, by bioassay-guided fractionation followed by chromatographic seperation of the water extract of Gyrophora esculenta, α-glucosidase inhibitor was isolated as GE974. GE974 showed significant inhibitory activities on some kinds of α-glucosidases in vitro. Its inhibitory mechanism seemed to be competitive for disaccharides. Also, it markedly inhibited α-glucosidases of intestine separated from both nondiabetics and diabetics.

스트레인 게이지 변위 추정기를 사용한 유동공진 가진기 개발

최재혁,남윤수 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.B

Heat dissipation technology using flow resonant phenomenon is a kind of new concept in heat transfer area. A vibration exciter is needed to generate air turbulence which has the natural shedding frequency of heat system. A mechanical vibrating device for the air flow oscillation is introduced, which is driven by a moving coil actuator. An analytical dynamic model for this mechanical vibration exciter is presented and its' validity is verified by the comparison with experimental data. Values of some unknown system parameters in the analytic model are estimated through the system identification approach. Based on this mathematical model, the vibration exciter using strain displacement estimator is developed. And in the experiment, the feedback control is used. During the experimental verification phase, it turns out the high modal resonant characteristics of vibrating plate are the major barrier against obtaining a high bandwidth vibration exciter.

한약수치에 관한 연구(제 9보) : 炒甘草 제법의 표준화 및 규격화(1) Preparing Standardization and Regulation of Stir-Frying Glycyrrhzia root(1)

최혁재,이우정,박성환,송보완,김동현,김남재 EAST-WEST MEDICAL RESEARCH INSTITUTE KYUNG HEE UNI 2005 東西醫學硏究所 論文集 Vol.2005 No.-

In this study, We carried out the preparing standardization and regulation of processed Glycyrrhizae Radix(PGR) which have been widely used in oriental medicines. Glycyrrhizae Radix(GR) have been generally prepared by the stir-frying, or mix-frying with honey for purpose of decreasing sweetness and augmenting vitality. Firstly, we tried to standardize PGR prepared by the stir-frying. We purchased 14 kinds of PGR and non-processed GR(NPGR) at oriental physician's offices and oriental pharmacies on a nation scale, respectively. The amounts of dry on loss, water extract, diluted ethanol extract, ether extract, total ash, acid insoluble ash, glycyrrhizin(GL), glycyrrhetic acid(GA) and liquiritin(LQ) of them were examined. The amounts of dray on loss, GL and LQ in commercial PGRs showed remarkable decrease, while GA showed increase as compared with NPGR. In order to standardize preparing method of PGR, the effect of heating time on physico-chemical parameters and biological activities were examined. Physico-chemical parameters such as dry on loss, extract amount, GL and LQ contents in PGRs showed decrease, however, GA was increased with heating time as compared with NPGR. Also, GA obtained form heat-treated GR, was found as an artifact in PGRs. PGR was more effective than NPGR in vitro test of DPPH scavenging effect and TBA-Rs reducing effect. PGR and NPGR showed potent hepatoprotective effect on CCl_(1)-intoxicated rats. Especially, PGR prepared by 80 min of heating was the most effective. Considering these results, the optimal condition for PGR preparation was 150℃ for 80min.

석이에서 분리한GE974의 혈당상승억제효과

최혁재,김남재,김동현 경희대학교 동서의학연구소 2001 東西醫學硏究所 論文集 Vol.2000 No.-

GE974, isolated from Gyrophora esculenta, showed significant inhibitory effect on several α-glucosidases in vitro in previous study. In the present study, GE974 showed significant inhibitory effect on blood glucose elevation in mice loaded with maltose, sucrose, starch and lactose. Also, it exhibited similar effect in alloxan and streptozotocin induced diabetic mice, and genetic diabetic mice(db/db mice) loaded with maltose in dose dependent manner. These results suggest that GE974 may possess hypoglycemic effect that inhibit competitively α-glucosidase activities.

흰쥐에서 Divalent Metal Transporter 1의 조직내 분포와 Iron에 의한 조절

최재혁,박정덕 한국환경독성학회 2004 환경독성보건학회지 Vol.19 No.4

Iron (Fe) is an essential metal in biological processes, which maintains a homeostasis in the human body Divalent metal transporter 1 (DMT1) has been known as an iron transporting membrane protein, which is involved in the uptake Fe at the apical portion of intestinal epithelium, and may transport Fe across the membrane of acidified endosome in peripheral tissues In this study, we studied the tissue distribution of DMT1 in the Fe supplemented (FeS) diet fed rats, and the regulation of DMT1 expression by depleting body Fe Sprague-Dawley rats were divided into two groups, and fed FeS (120mg Fe/kg) diet or Fe deficient (FeD, 2~6mg Fe/kg) diet for 4 weeks The evaluation of body Fe status was monitored by measuring sFe, UIBC and tissue Fe concentration Additionally, DMT1 mRNA levels were analyzed in the peripheral tissues by using the quantitative real time RT-PCR method In the FeS diet fed rats, the tissue Fe was maintained at a relatively high level, and DMT1 was eventually expressed in all tissues studied DMT1 was highly expressed in the testis, kidney and spleen, while a moderate levels of DMT1 expression was detected in the brain, liver and heart In the digestive system, the highest level of DMT1 was found in the duodenum Feeding the FeD diet caused a reduced body weight gain and depletion of body Fe with finding of decreased sFe, increased UIBC and decreased tissue Fe concentration The depletion of body Fe upregulated DMT1 expression in the peripheral tissue The expression of DMT1 was very sensitive to the body Fe depletion in the small intestine, especially in the duodenum, showing dramatically higher levels in the FeD rats than those of the FeS group In the FeD diet fed animals, the expression of DMT1 was low significantly in other tissues compared with the duodenum The expression of DMT1, however, was 60~120% higher in the testis, kidney and spleen, and 30~50% higher in the lung, liver and heart, compared to the FeS diet fed rats In summary, DMT1 expression was ubiquitous in mammalian tissue, and the level of expression was the organ-dependent The expression of DMT1 in peripheral tissues was upregulated by depletion of body Fe Duodenum was the most sensitive tissue among organs studied during Fe depletion, and expressed the greatest level of DMT1, while other tissues were less higher than in duodenum This study supports that DMT1 plays a role in maintaining the body Fe level through intestinal uptake as well as homeostasis of Fe in the peripheral tissue.

環境的 아이덴티티의 認知次元에 관한 硏究

河在明,崔武革 慶北大學校 1991 論文集 Vol.51 No.-

This thesis aims at studying one of the ways which grasps exactly environmental qualities. For this purpose, this paper examines the cognitive dimensions of environmental identity which is the identity that a person or group has with his environment, in particular when he is experiencing it as an insider. There are two important dimensions: the vertical dimension and the horizontal dimension. The vertical dimension is classified by the degree of relationship between the observer and the environment. The horizontal dimension is classified by the scale of the environment concerned with its users.

부하분산 및 결함허용을 제공하는 CORBA 기반 원격 회의 시스템 설계

성재철,임주혁,장우혁,조찬윤,최항묵 인제대학교 1999 仁濟論叢 Vol.15 No.1

인터넷 및 통신 기술의 발달에 따라 원격 회의 시스템이나 원격 교육, 가상 대학과 같은 응용에 대한 연구가 활발히 진행되고 있다. 이와 판은 시스템에 기존의 중앙 집중 방식을 사용할 경우에는 서버측의 부하가 모두 집중되어 전체 시스템에 영향을 미치게 될 수 있으므로 분산 시스템을 이용한 연구가 활발히 진행되고 있다. 본 논문에서는 이미지나 텍스트-파일과 같은 자료를 필요로 하는 원격 회의 시스템을 설계하고 Factory 객체와 관계형 통합 데이터 베이스를 이용하여 동적 부하 분산과 동적 결함 허용을 제공하는 시스템을 제안한다. As the technigues of the Interned and Communication are developed, the study about its applications such as Remote Conference system, Remote Education and Cyber University are lively progressing. When the centralized method is applied to those kinds of system mentioned above, the load is mostly occurred in the server side anaitcauas bad effect to the whole system. So the Study about an application such as Remote Conference system, Remote Education and Cyber University is considering using the distributed system. In this paper I would like design a Remote Conference System is soogetled, which needs sub data like images, text files and givers dynamic load balance and dynamic fault tolerance using Factory object and Relational Integrated Data Base.

우리나라 임도의 현황과 활용방안에 관한 고찰

김도경,최재혁 경희대학교 디자인연구원 2000 예술· 디자인학연구 Vol.3 No.1

The purpose of this study is the first step to investigate the practical use of Korean forest roads by surveying its present conditions. In Korea, forest reaches 65% of the country, but the density of forest roads is only 2.24km/1,000ha far behind compared to the density in developed countries. The Korean government is planning systematic approaches on existing forest roads using FGIS(Forest roads Geographical Information System) and also is planning to expand the forest roads with a long-range policy. However, the current tendency towards forest recreation planning is still oriented on allowing new facilities for forest recreation rather than developing programs for forest recreation by connecting existing facilities with forest roads. This program oriented approaches using forest roads for forest recreation planning can reduce damages on forest environment substantially compared to facility oriented planning approaches. Further studies are required to develop programs using forest roads for forest recreation.