• Title/Summary/Keyword: Gil-ho Kim

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Protective Effect of Acanthopanax senticosus on Oxidative Stress Induced PC12 Cell Death

  • Choi, Soo-Jung;Yoon, Kyung-Young;Choi, Sung-Gil;Kim, Dae-Ok;Oh, Se-Jong;Jun, Woo-Jin;Shin, Dong-Hoon;Cho, Sung-Hwan;Heo, Ho-Jin
    • Food Science and Biotechnology
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    • v.16 no.6
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    • pp.1035-1040
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    • 2007
  • Epidemiologic studies have shown important relationships between oxidative stress and Alzheimer's disease (AD) brain. In this study, free radical scavenging activity and neuronal cell protection effect of aqueous methanol extracts of Acanthopanax senticosus (A. senticosus) were examined. $H_2O_2$-induced oxidative stress was measured using 2',7'-dichlorofluorescein diacetate (DCF-DA) assay. Pretreatment with the phenolics of A. senticosus prevented oxidative injury against $H_2O_2$ toxicity. Since oxidative stress is known to increase neuronal cell membrane breakdown, leading to cell death, lactic dehydrogenase release, and trypan blue exclusion assays were utilized. We found that phenolics of A. senticosus have neuronal cell protection effects. It suggests that the phenolics of A. senticosus inhibited $H_2O_2$-induced oxidative stress and A. senticosus may be beneficial against the oxidative stress-induced risk in AD.

Comparative Study on the Nucleus accumbens septi and the Nucleus fundus striati III. Changes in the Neuropil following the Lesion in the Mamillary Body or the Extirpation of Hippocampal Formation (중격측좌핵과 선조체 기저핵의 비교연구 III. 유두체 손상과 해마제거의 영향)

  • Ahn, E-Tay;Kim, Jong-Kyu;Yang, Nam-Gil;Ko, Jeong-Sik;Lee, Bong-Hee;Park, Kyung-Ho
    • Applied Microscopy
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    • v.18 no.1
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    • pp.35-48
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    • 1988
  • To investigate the connections between the major limbic structures and the nucleus accumbens septi or the nucleus fundus striati, stereotaxic surgeries were performed. One group of the rats were electrically lesioned in the mamillary body, and the other group were extirpated their hippocampal formation. Careful study of both nuclei following each surgery showed the following results. 1. Nerve terminals of mamillo-accumbens tract were synapsed to the dendrite of nucleus accumbens cell, whereas the neuronal type of accumbens-mamillary tract was aspiny cell. 2. Nerve terminals of mamillo-fundus tract were synapsed to the spines of fundus striati cells. Fundus-mamillary tract cells were not confirmed. 3. Nerve terminals of hippocampo-accumbens terminals were synapsed to the dendrites and spines of nucleus accumbens cells, whereas the neuronal type of accumbens-hippocampal tract was spiny one. 4. Nerve terminals of hippocampo-fundus tract were synapsed to the spines of fundus striati cells, whereas the neuronal types of fundus-hippocampal tract was aspiny one. 5. From the results, it was concluded that both of the nucleus accumbens septi and the fundus striati have connections with the mamillary body and the hippocampus. But nucleus accumbens septi has apparently more intimate relationship with major limbic structures.

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Ultrastructural Study on the Substantia Nigra of the Head-Irradiated Rats (머리에 방사선 상해를 받은 흰쥐 흑색질의 미세구조)

  • Bae, Hack-Gun;Yang, Nam-Gil;Ahn, E-Tay;Ko, Jeong-Sik;Park, Kyung-Ho;Kim, Jin-Gook
    • Applied Microscopy
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    • v.22 no.2
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    • pp.30-45
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    • 1992
  • An experimental study on the acute irradiation effects on the substantia nigra of head-irradiated rats were carried out. Rats anesthetized with sodium thiopental, were exposed only on their head areas with a single dose of 3,000 rads or 6,000 rads, respectively. Radiation was produced by Mitsubishi linear accelerator at the speed of 200 rads/min. Aminals were sacrificed on 6 hours, 2 days and 6 days following irradiations. By the perfusion fixation through the heart, rats were fixed with 1% glutaraldehyde-1% paraformaldehyde solution. Two hours later, brains were exposed and immersed in the same fixatives over night. Tissue blocks from subtantia nigra were punched out, and they were refixed in the 2% osmium tetroxide solution. Blocks were dehydrated through alcohol series, and embedded in the araldite mixture. Ultrathin sections were stained with uranyl acetate and lead citrate solutions, From the ultrastructural study, following results were made: 1. Six hours after irradiation, severe depletion of synaptic vesicles was occurred in the many axon terminals of the nigral neuropil. 2. Dramatical decrease of lysosomes and dense granules was observed. 3. Two days following irradiation, alterations of ribosomes, granular endoplasmic reticula, mitochondria, etc, were noticed. 4. Many of the malformations were seen to be repaired on the 6th day. 5. Above results were interpreted as follows. At the acute stage of heavy irradiation, neurotransmitters in the substantia nigra are released severely. But they are recovered within 6 days. It is concluded that acute head-irradiation may result severe disturbance of nigral motor control function during the first few days.

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Two Dinucleotide Repeat Polymorphisms (AC/TG and GT/CA) in the 5' Upstream Region of the Mouse Tryptophan Hydroxylase Gene

  • Yim, Sung-Vin;Chi, Sung-Gil;Chung, Sung-Hyun;Lee, Hee-Jae;Kim, Mi-Ja;Park, Seung-Joon;Jung, Jee-Chang;Chung, Joo-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.5
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    • pp.501-505
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    • 1999
  • Tryptophan hydroxylase (TPH), the rate-limiting enzyme in serotonin biosynthesis, is primarily expressed in serotonergic neurons of the raphe nuclei. Simple tandem repeat polymorphisms, typically one to four nucleotides long, are tandemly repeated several times and often characterized by many alleles. To identify the presence of polymorphic repeats, we sequenced the 5'-upstream region of the mouse TPH gene. For the detection of any allelic variants, polymerase chain reaction, nonisotopic single-strand conformation polymophism, and DNA sequencing analyses of the tandem repeat sequences were performed using genomic DNA extracted from 60 ICR mice. Two dinucleotide repeats, $5'-(AC/TG)_{22}-3'$ and $5'-(GT/CA)_{17}3',$ were identified at approximately - 5.7 kb and - 3.4 kb upstream from the transcriptional initiation site of the mouse TPH gene, respectively. Minor allelic variants, $5'-(AC/TG)_{21}-3'$ and $5'-(GT/CA)_{18}-3',$ were observed in heterozygous pairs from 3 of 60 and 1 of 60 ICR mice, respectively. The identification of these microsatellites in the mouse TPH promoter raises the possibility that identical and/or other polymorphic sequences might exist in the upstream region of the human TPH gene.

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Bibliographic Study on the Moschus used to Acute Stage of Stroke (중풍급성기(中風急性期)에 활용(活用)되는 사향(麝香)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Huh, Jae-Hyeok;Kim, Sae-Gil;An, Ill-Hoe;Shin, Sun-Ho;Moon, Byung-Soon;Sung, Gang-Kyung
    • The Journal of Korean Medicine
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    • v.16 no.2 s.30
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    • pp.100-114
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    • 1995
  • This bibliographic study was designed to research indications of the Moschus which was representatively used for resuscitation in acute stage of stroke throughout successive books of oriental medicine. Especially, in this study, severe cases with disturbance of consciousness and acute stage of stroke were investigated. The results were summarized as the followings: 1. The Moschus was dried material which secreted from aromatic vescicle of Moschus moschiferus L.. which was pungent in flavor, warm in nature, nontoxic and strongly aromatic. The Moschus removed the obstruction in the channels and used to early stage of stroke. 2. The Moschus was aromatic resuscitatable medicine, which recovered disturbance of consciousness due to stroke. 3. The Moschus had excitatory actions of respirtory center and vascular motor center, heart stimulating action, inhibitatory action of the platelet aggregation and anti thrombin action and recovered cerebral ischemic change. According to these actions, the Moschus could be used cerebral infarction. 4. Prescriptions included the Moschus was used to symptoms of unconsciousness, secretion, stuporous mental state, dysarthria, facial palsy and hemiplegia. That was Angungwoohwangh wan(安宮牛黃丸), Woohwangchungshimwon(牛黃淸心元), Sahyangsohaphangwon(麝香蘇合香元), etc. According to the above mentioned results, the Moschus was aromatic resuscitatable medicine which was used for symptoms of conscius disturbance, convulsion, sudden fainting etc., promoted cerebral blood flow and had good effect on acute stage of stroke and severe cases with conscious disturbance. Therefore, it is considered that the Moschus must be studied for effect of cerebral infarction and hemorrhage in clinic with animal's and pharmacological experimental results.

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Effect of CaMgSn Ternary Phase on the Aging Response of Mg-Sn-Zn-Ca Alloys

  • Wahid, Shah Abdul;Lim, Hyun-Kyu;Jung, Young-Gil;Yang, Won-Seok;Ha, Seong-Ho;Yoon, Young-Ok;Kim, Shae K.
    • Journal of Korea Foundry Society
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    • v.38 no.4
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    • pp.75-81
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    • 2018
  • This study examined the effect of the CaMgSn ternary phase on the aging response of the Mg-Sn-Zn alloy. The results revealed that the CaMgSn ternary phase formed in rod-like or needle-like shapes in Mg-3Zn-0.3Ca-xSn (x=1.5, 3, and 5 wt%) alloys and its size decreased as the Sn content increased from 1.5 wt% to 5 wt%. The Mg-3Zn-0.3Ca-5Sn alloy with a relatively fine CaMgSn phase was subjected to solution heat treatment and an aging process. Both the Mg-5Sn-3Zn-0.3Ca and Mg-5Sn-3Zn (base alloy) alloys had similar peak hardness values throughout all aging temperatures but the time-to-peak hardness in the Mg-5Sn-3Zn-0.3Ca alloy was 24-36 hours-earlier than that in the base alloy. Precipitates in the Mg-5Sn-3Zn-0.3Ca alloy were more refined than those in the Mg-5Sn-3Zn alloy and were mostly formed on basal planes. The $Mg_2Sn$ phase formed in either plate-like or rod-like shapes in the Mg-5Sn-3Zn alloy, whereas block-shaped $Mg_2Sn$ particles also formed in the Mg-5Sn-3Zn-0.3Ca alloy.

Differentiation in Pathogenicity of Alternaria kikuchiana Tanaka, Black Spot Fungus of Pear, and Conversion of Resistant Varieties into Susceptible ones (배나무 검은무늬병균(Alternaria kikuchiana Tanaka)에 병원성분화와 저항성품종의 이병화)

  • Ki Un Kye;Park Seur Kee;Cho Back Ho;Kim Ki Chung
    • Korean journal of applied entomology
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    • v.23 no.1 s.58
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    • pp.7-14
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    • 1984
  • Recently, a symptom similiar to black spot caused by Alternaria kikuchiana on the pear leaves is prevailing in Naju, Chonnam Province. This experiment was conducted in order to clarify causal agent and to survey present status on it. Disease lesions on the leaves were brown or black brown in color, circle or irregular circle in shape, $2\~6mm$ in diameter, and faintly zonal. Central part of lesions was gradually changed to greyish-white. The causal fungus was identified as Alternaria kikuchiana Tanaka causing black spot of pear reported previously on variety I-sib-se-gi (Nijisseki) of pear. However, this disease differed from that of typical black spot reported already in some aspects; It occurred more highly on matured leaves than on young ones. And it occurred severely in varieties Shin-heung, Shin-ko, Man-sam-gil(Okusankichi) etc. which have been reported as resistant varieties, while slightly in varieties Cho-ok(Hayadama), Park-da-cheung (Hakadahare) etc. which have been known as susceptible ones. From the results described above, it is considered that this disease is due to the differentiation in pathogenicity of Alternaria kikuchiana Tanaka in that area.

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Ultrastructural Influence of Nephrotoxic Agents on the Juxtaglomerular Cells of Mice (신장 상해물질이 생쥐 사구체곁세포의 미세구조에 미치는 영향)

  • Park, Kyung-Ho;Kim, Sang-Chul;Ahn, E-Tay;Ko, Jeong-Sik;Yang, Nam-Gil
    • Applied Microscopy
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    • v.26 no.4
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    • pp.431-446
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    • 1996
  • This experiment was performed to study the ultrastructural changes of the juxtaglomerular cell of mice following subcutaneous injection of heavy metallic agents. Male mice were divided into normal and experimental groups. The mice were subcutaneouly injected with $HgCl_2$ (2mg, 5mg or 10 mg/Kg/BW) or with $K_{2}Cr_{2}O_7$(5 mg, 10 mg or 20 mg/Kg/BW). Mice were sacrificed on 6 hours, 3 days and 14 days after the injection. Kidneys were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture. The sections were cut on a LKB-V ultratome, and ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100CX II electron microscope. The results were as follow: 1. Juxtaglomerular cell of the experimental groups showed some alterations, especially in the structures of protein synthesis including dilations and degradations of granular endoplasmic reticula, atrophy of Golgi complex, and numerous free ribosomes in the cytoplasm. 2. Juxtaglomerular cells treated groups showed a number of vacuoles, protogranules and some myelin figures in the cytoplasm, especially in the earlier groups. 3. Juxtaglomerular cells of treated groups, contained a large number of secretory granules showing variable electron densities and pleomorphism in later groups (2 weeks). From the above results, it was concluded that, the mercuric chloride or potassium bichromate induces acute renin release from juxtaglomerular cells of the mice, but many juxtaglomerular cells may secrete prematured secretory granules, or the synthetic system of the cell can not perform normal function.

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A Routing Protocol for Assuring Scalability and Energy Efficiency of Wireless Sensor Network (WSN의 확장성과 에너지 효율성을 보장하는 라우팅 프로토콜)

  • Jeong, Yoon-Su;Kim, Yong-Tae;Park, Gil-Cheol;Lee, Sang-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.105-113
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    • 2008
  • While the wireless sensor network has a strong point which does not have effect on whole activities of network even though neighboring sensor nods fail activities of some sensor nod or make some functions disappear by the characteristic of similar information detection, it has problems which is slowing down of wireless medium, transfer character with severe error, limited power supply, the impossibility of change by optional arrangement of sensor nods etc. This paper proposes PRML techniques which performs the fittest course searching process to reduce power consumption of entire nods while guarantees the scalability of network organizing sensor nods hierarchically. The proposed technique can scatter the load of cluster head by considering the connectivity with surplus energy of nod and reduce the frequency of communication among the nods. As a result of the analysis in comparison with LEACH-C and HEED technique, PRML technique get efficiency of average 6.4% in energy consuming respect of cluster head, efficiency of average 8% in entire energy consuming respect, and more efficiency of average 7.5% in other energy consuming distribution of network scalability than LEACH-C and HEED technique.

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Crystal Structure of GRIP1 PDZ6-peptide complex reveals the structural basis for class II PDZ target recognition and PDZ domain-mediated multimerization

  • Im, Young-Jun;Park, Seong-Ho;Park, Seong-Hwan;Lee, Jun-Hyuck;Kang, Gil-Bu;Morgan Sheng;Kim, Eunjoon;Eom, Soo-Hyun
    • Proceedings of the Korea Crystallographic Association Conference
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    • 2002.11a
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    • pp.4-4
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    • 2002
  • PDZ domains bind to short segments within target proteins in a sequence-specific fashion. GRIP/ABP family proteins contain six to seven PDZ domains and interact via its sixth PDZ domain (class Ⅱ) with the C-termini of various proteins, including liprin-α. In addition the PDZ456 domain mediates the formation of homo- and heteromultimers of GRIP proteins. To better understand the structural basis of peptide recognition by a class Ⅱ PDZ domain and DZ-mediated multimerization, we determined the crystal structures of the GRIPI PDZ6 domain, alone and in complex with a synthetic C-terminal octapeptide of human liprin-α, at resolutions of 1.5 Å and 1.8 Å, respectively. Remarkably, unlike other class Ⅱ PDZ domains, Ile736 at αB5 rather than conserved Leu732 at αB1 makes a direct hydrophobic contact with the side chain of the Tyr at the -2 position of the ligand. Moreover, the peptide-bound structure of PDZ6 shows a slight reorientation of helix αB, indicating that the second hydrophobic pocket undergoes a conformational adaptation to accommodate the bulkiness of the Tyr's side chain, and forms an antiparallel dimer through an interface located at a site distal to the peptide-binding groove. This configuration may enable formation of GRIP multimers and efficient clustering of GRIP-binding proteins.

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