• Title/Summary/Keyword: Seong-Ho School

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Up-regulation of Heme Oxygenase-1 by Korean Red Ginseng Water Extract as a Cytoprotective Effect in Human Endothelial Cells

  • Yang, Ha-Na;Lee, Seung-Eun;Jeong, Seong-Il;Park, Cheung-Seog;Jin, Young-Ho;Park, Yong-Seek
    • Journal of Ginseng Research
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    • v.35 no.3
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    • pp.352-359
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    • 2011
  • Korean red ginseng (KRG) is used worldwide as a popular traditional herbal medicine. KRG has shown beneficial effects on cardiovascular diseases, such as atherosclerosis, diabetes, and hypertension. Up-regulation of a cytoprotective protein, heme oxygenase (HO)-1, is considered to augment the cellular defense against various agents that may induce cytotoxic injury. In the present study, we demonstrate that KRG water extract induces HO-1 expression in human umbilical vein endothelial cells (HUVECs) and possible involvement of the anti-oxidant transcription factor nuclear factor-eythroid 2-related factor 2 (Nrf2). KRG-induced HO-1 expression was examined by western blots, reverse transcriptase polymerase chain reaction and immunofluorescence staining. Specific silencing of Nrf2 genes with Nrf2-siRNA in HUVECs abolished HO-1 expression. In addition, the HO inhibitor zinc protoporphyrin blunted the preventive effect of KRG on $H_2O_2$-induced cell death, as demonstrated by terminal transferase dUTP nick end labeling assay. Taken together, these results suggest that KRG may exert a vasculoprotective effect through Nrf2-mediated HO-1 induction in human endothelial cell by inhibition of cell death.

Characterization of Arabidopsis RopGEF family genes in response to abiotic stresses

  • Shin, Dong Ho;Kim, Tae-Lim;Kwon, Yong-Kook;Cho, Man-Ho;Yoo, Jihye;Jeon, Jong-Seong;Hahn, Tae-Ryong;Bhoo, Seong Hee
    • Plant Biotechnology Reports
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    • v.3 no.3
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    • pp.183-190
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    • 2009
  • Rho-related GTPase of plants (ROP) plays an important role in plant growth and development as a signaling protein. Plant RopGEFs are recently identified ROP activator proteins in Arabidopsis. In this study, we cloned 14 RopGEFs in Arabidopsis and characterized their expression patterns in response to abiotic stresses. Fourteen RopGEF genes were categorized into three groups based on their amino acid homologies and molecular sizes. Most RopGEFs were expressed predominantly in flower but some RopGEFs displayed a tissue-specific expression pattern. RopGEF1, 4, 5, and 11 were expressed in all tissues including root and leaves whereas RopGEF7, 8, 9, and 13 were expressed only in flowers. The transcript levels of 14 RopGEFs were changed significantly depending upon abiotic stresses such as cold, heat, drought and salts. RopGEF5 transcription was up-regulated by salt and drought treatment but down-regulated by heat. RopGEF14 transcript level was also increased by salt but decreased by heat stress. The transcript levels of RopGEF1, 7, 9, and 12 were enhanced in response to heat stress but showed no changes in response to cold stresses. Drought stress activated Group 3 RopGEFs such as RopGEF5 and 7. Taken together, 14 RopGEFs are responding to the abiotic stresses individually or as a group.

3D/2D convertible color display based on modified integral imaging

  • Kim, Yun-Hee;Cho, Seong-Woo;Lee, Byoung-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1318-1321
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    • 2006
  • We describe the 3D/2D convertible color display based on modified integral imaging. In the proposed method a color liquid crystal display panel is used as a transmission-type display panel and enables a color 3D/2D convertible display system. The principle of the proposed method will be explained and methods to overcome the color dispersion problem will be discussed also.

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Analysis on the effect of color dispersion compensating layer in the three-dimensional/two-dimensional convertible display based on parallax barrier

  • Cho, Seong-Woo;Park, Jae-Hyeung;Lee, Byoung-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1599-1602
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    • 2005
  • In a three-dimensional/two-dimensional convertible parallax barrier display, an additional layer compensating the color dispersion for three-dimensional display can distort displayed image in the two-dimensional mode. We analyze the effect of the color dispersion compensating layer on two-dimensional image by computer simulations.

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Effects of turbulent boundary layer thickness on flow around a low-rise rectangular prism

  • Kim, Kyung Chun;Ji, Ho Seong;Seong, Seung Hak
    • Wind and Structures
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    • v.8 no.6
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    • pp.455-467
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    • 2005
  • The effects of upstream velocity profiles on the flow around a low-rise rectangular prism submerged in a turbulent boundary layer have been investigated. Three different boundary layer profiles are generated, which are characterized by boundary layer height, displacement thickness, and momentum thickness. Flow characteristics variations caused by the different layers such as those in turbulent kinetic energy distribution and locations of re-circulating cavities and reattachment points have been precisely measured by using a PIV (Particle Image Velocimetry) technique. Observations were made in a boundary layer wind tunnel at $Re_H$=7900, based on a model height of 40 mm and a free stream velocity of 3 m/s with 15 - 20% turbulence intensity.