• Title/Summary/Keyword: Lee Sam

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Formation and Production of Ascorbate Oxidase by Cucumber Tissue Cultured Cells (오이조직 배양세포에 의한 Ascorbate Oxidase 생성 및 생산)

  • Lee, Jong-Hwa;Chung, Ho-Kwon;Shinmyo, Atsuhiko;Lim, Bun-Sam
    • Microbiology and Biotechnology Letters
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    • v.21 no.4
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    • pp.329-335
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    • 1993
  • Ascorbate oxidase activity in various cucumber tissue extracts was highest in young fruit peeling. Cucumber callus was induced from young fruit peeling and callus cell lines were selected for more than 7 months, which porduced high levels of ascorbate oxidase and had a high growth rate. Induction of callus was optimized with Linsmaier-Skoog(LS) medium at 25$^{\circ}C$ in dark phase. Ascorbate oxidase activity reached a maximum at 5 days after transfer to LS basal liquid-medium ant then declined. The enzyme activity in callus cells was stimulated by addition of 10${\mu}$M $CuSO_4$ in the early logarithmic phase of growth. And also, adding 10${\mu}$M $CuSO_4$ at 3rd day 7th day of culture period, ascorbate oxidase activity in callus cells was maintained to high level. Maximum yield of ascorbate oxidase was found at the 25th day by flask shaking culture, but three-fold of ascorbate oxidase activity was obtained at the 16th day by jar fermentation.

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Development of Vegetable Soybeans Thresher (II) - Threshing and separating characteristic - (풋콩 탈협기 개발을 위한 기초 연구 (II) - 탈협 및 선별 특성 -)

  • Kim T H.;Lim H. K.;Lee J. T.
    • Journal of Biosystems Engineering
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    • v.29 no.5 s.106
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    • pp.433-440
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    • 2004
  • Worldwide consumption of vegetable soybean has been increasing recently, but in the process of vegetable soybean production, threshing and separation work accounts fur about $80\%$ of overall labor. Therefore, developing of the vegetable soybean thresher is necessary to reduce the cost of labor. The main objective of this study is to acquire the basic in-formations for design of the vegetable soybean thresher which is suitable for domestic circumstances. We made the experimental system to investigate the threshing and separating performance at the several speeds of threshing cylinder and separating blower according to the kinds of threshing tooth. The result are as follows; Threshing performance of vegetable soybean thresher was shown as the best in case the threshing tooth made of rubber which has the 80 of Shore hardness was used at the circumference speed of cylinder of 5.8$\~$8.1m/s. Also separating cleaning performance of vegetable soybean thresher was shown as the best at more than 1,300 rpm of blower speed and $60\~80\%$ of opening ratio of suction port.

Genetic Homogeneity of the Korean Native Bumble Bee, Bombus ardens (Hymenoptera: Apidae), Detected by Mitochondrial COI Gene Sequences

  • Yoon, Hyung-Joo;Kim, Sam-Eun;Lee, Myeong-Lyeol;Kim, Iksoo;Bae, Jin-Sik;Sohn, Hung-Dae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.6 no.1
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    • pp.63-68
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    • 2003
  • We investigated the sequence divergence of the geographic samples of the queen bumble bee (Bombus ardens) in Korea. A portion of mitochondrial COI gene sequences (423 bp) was analyzed for 44 individuals collected from seven localities. Sequence analysis resulted in four COI haplotypes with the maximum nucleotide divergence of only 0.5% (two bp). One haplotype (BA1) was dominant in all localities surveyed (86.4%). The finding of low sequence divergence and dominance of one haplotype appear to reflect, although limited, the life history of the B. ardens queens subjected to active dispersal and seasonal fluctuation in queen number.

Comparative Analysis of Completely Sequenced Insect Mitochondrial Genomes

  • Lee, Jin-Sung;Kim, Ki-Hwan;Suh, Dong-Sang;Park, Jae-Heung;Suh, Ji-Yoeun;Chung, Kyu-Hoi;Hwang, Jae-Sam
    • International Journal of Industrial Entomology and Biomaterials
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    • v.2 no.1
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    • pp.1-6
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    • 2001
  • This paper reports a few characteristics of seven insect mitochondrial genomes sequenced completely (Bombyx mori, Drosophila melanogaster, D. yakuba, Apis mellifera, Anopheles gambiae, A. quadrimaculatus, and Locusta migratoria). Comparative analysis of complete mt genome sequences from several species revealed a number of interesting features (base composition, gene content, A+T-rich region, and gene arrangement, etc) of insect mitochondrial genome. The properties revealed by our work shed new light on the organization and evolution of the insect mitochondrial genome and more importantly open up the way to clearly aimed experimental studies for understanding critical roles of the regulatory mechanisms (transcription and translation) in mitochondrial gene expression.

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Colony Developmental Characteristics of the Bumblebee Queen, Bombus ignitus by the First Oviposition Day

  • Yoon, Hyung-Joo;Kim, Sam-Eun;Kim, Young-Soo;Lee, Sang-Beom
    • International Journal of Industrial Entomology and Biomaterials
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    • v.8 no.2
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    • pp.139-143
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    • 2004
  • It was investigated whether developmental characteristics of foundation queens of Bombus ignitus collected in the 4 localities in Korea would be affected by the first oviposition days of them. The first ovipostion day was classified as 1-4 days (immediate early), 5-6days (early), 7-10 days (delayed early), 11-20 days{medium), 21- 40 days (late), and above 41 days (very late). The queen that had the early first oviposition day, i.e., laid eggs so early after starting to be raised indoors, showed much higher rate of colony foundation and progeny-queen production and much shorter period of colony foundation and worker emergence. Besides, the numbers of worker and progeny-queen emerged from the queen that had the early first oviposition day were higher than those of the queen that had the late first oviposition. In results, the queen that had the early first oviposition day could make colony stronger and could make colony formation period shorter, therefore, the first oviposition day of foundation queen was proved to be a criterion for the selection of super colonies when B. ignitus is raised indoors.

Construction of the Full-length cDNA Library and Selection of Diapause-Associated cDNA Clones from Bombyx mori Diapausing Eggs and Diapause-Activated Eggs

  • Hwnag, Jae-Sam;Go, Hyun-Jeong;Goo, Tae-Won;Yun, Eun-Young;Choi, Kwang-Ho;Seong, Su-Il;Kim, Sung-Kuk;Lee, Sang-Mong;Kim, Iksoo;Kim, Nam-Soon;Kang, Seok-Woo
    • International Journal of Industrial Entomology and Biomaterials
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    • v.9 no.1
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    • pp.145-148
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    • 2004
  • As an initial step to define the molecular mechanism of diapause during embryogenesis of the silkworm, Bombyx mori, mRNA transcripts from diapausing eggs and diapause-activated eggs were compared by differential expression using cDNA microarray. Twenty-four individual cDNA clones were identified. Amomg them, ten genes including alcohol dehydrogenase, dead box-l, cytochrome oxidase subunit I and 18 wheeler showed increased expression in the diapause-activated eggs. The rest of fourteen genes showed increased expression in diapausing eggs.

Development of Improved Pixel Enhancement Actuator for DLP Projection TV (DLP 프로젝션 TV의 화소 증진 엑추에이터 개발)

  • Yun, Gi-Tak;Kim, Jae-Eun;Lee, Kyung-Taek;Hong, Sam-Nyol;Ko, Eui-Seok;Hahn, Sang-Hoon;Koo, Hee-Sool
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.463-466
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    • 2005
  • While recent display devices are becoming light and slim, the size of a screen is especially the important issue in the field of display devices. Furthermore, it is also required that the projection TV, a large screen display device, be able to represent higher resolutions as the digital broadcasting is set off. In order to realize high resolutions in a DLP projection TV, the number of pixel on DMD should be increased. However, a large number of pixels make it difficult to realize resulting small sized pixels and this cause the increase in cost. Therefore, we propose a simple and improved pixel enhancement actuator using the existing DMD by offsetting half pixels repeatedly in the vertical direction.

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Taxonomy and distribution of Corycaeidae (Copepoda: Cyclopoida) in the Korean Waters in Summer (한국 연근해에서 하계에 출현하는 Corycaeidae (Copepoda : Cyclopoida)의 분류 및 분포)

  • KANG, YOUNG SHIL;HUH, SUNG-HOI;LEE, SAM SEUK
    • 한국해양학회지
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    • v.25 no.2
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    • pp.49-61
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    • 1990
  • The family Corycaeidae in the neighbouring seas of Korea was taxonomically studied based on the zooplankton samples collected in August, 1986. In this study, nine species belonging to two genera and three subgenera of the Corycaeidae were identified and described with illustrations; Corycaeus (Corycaeus) speciosus, G.(C.) crassiusculus, C. (Ditrichocorycaeus) affinis, C.(D.) andrewsi, C.(D.) erythraeus, C.(Onychocorycaeus) pacificus, c.(O.) catus, C.(O.) agilis, and Farranula gibbula. The distribution patterns of these species showed that C.(D.) affinis appeared to be and indicator species of the coastal waters, and C.(C.) speciosus, C.(C.) crassiusculus, c.(O.) catus, C.(D.) andrewsi, and Farranula gibbula appeared to be indicator species of the warm-oceanic waters.

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Isolation of Torilin from Torilis japonica Fruit and Its Analgesic and Anti-inflammatory Activities (사상자 중 Torilin의 분리 및 진통소염작용)

  • Cho, Sung-Ig;Kang, Sam-Sik;Kim, Kyung-Ran;Kim, Tae-Hee;Lee, Eun-Bang
    • Korean Journal of Pharmacognosy
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    • v.30 no.2
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    • pp.137-144
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    • 1999
  • Torilin was isolated from haxane fraction of Torilis Fructus extract. Torilin produced inhibition of the acetic acid-induced and phenylquinone-induced writhing syndrome at the oral doses of 30 and 90 mg/kg in mice. It also increased the pain threshold at the oral doses of 30, 90 and 270 mg/kg in the tail pressure method and the Randall-Selitto method. However, it did not show a hypothermic action at the oral doses of 30 and 90 mg/kg in mice. The compound exhibited strong anticarrageenan activity at the oral doses of 90 and 270 mg/kg in rats, and had inhibitory effect on the vascular permeability at the oral doses of 30 and 90 mg/kg in mice. It also showed potent inhibition of leucocyte emigration in CMC-pouch at the doses of 3 and 9 mg/rat, sc. The acute toxicity of torilin was very weak: the $LD_{50}$ values were more than 5000 mg/kg, po and 2000 mg/kg, ip in mice. From the above mentioned results, it was suggested that torilin had potent analgesic and anti-inflammatory activities.

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Growth Inhibitory Activity of Honokiol through Cell-cycle Arrest, Apoptosis and Suppression of Akt/mTOR Signaling in Human Hepatocellular Carcinoma Cells

  • Hong, Ji-Young;Park, Hyen Joo;Bae, KiHwan;Kang, Sam Sik;Lee, Sang Kook
    • Natural Product Sciences
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    • v.19 no.2
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    • pp.155-159
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    • 2013
  • Honokiol, a naturally occurring neolignan mainly found in Magnolia species, has exhibited a potential anti-proliferative activity in human cancer cells. However, the growth inhibitory activity against hepatocellular carcinoma cells and the underlying molecular mechanisms has been poorly determined. The present study was designed to examine the anti-proliferative effect of honokiol in SK-HEP-1 human hepatocellular cancer cells. Honokiol exerted anti-proliferative activity with cell-cycle arrest at the G0/G1 phase and sequential induction of apoptotic cell death. The cell-cycle arrest was well correlated with the down-regulation of checkpoint proteins including cyclin D1, cyclin A, cyclin E, CDK4, PCNA, retinoblastoma protein (Rb), and c-Myc. The increase of sub-G1 peak by the higher concentration of honokiol ($75{\mu}M$) was closely related to the induction of apoptosis, which was evidenced by decreased expression of Bcl-2, Bid, and caspase-9. Hohokiol was also found to attenuate the activation of signaling proteins in the Akt/mTOR and ERK pathways. These findings suggest that the anti-proliferative effect of honokiol was associated in part with the induction of cell-cycle arrest, apoptosis, and dow-nregulation of Akt/mTOR signaling pathways in human hepatocellular cancer cells.