• Title/Summary/Keyword: Lee Joon Gu

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Inhibitory Effect of Some Natural Polyphenols Isolated from Euphorbiaceae Plants on Melanogenesis (대극과 식물로부터 분리한 천연폴리페놀의 멜라닌 생성 억제효과)

  • Kim, Jeong-Ah;Choi, Ji-Young;Son, Ae-Ryang;Park, Sung-Hee;Xu, Guang-Hua;Lee, Jong-Gu;Oh, In-Suk;Kim, Jin-Joon;Chang, Hyun-Wook;Chung, See-Ryun;Jang, Tae-Soo;Lee, Seung-Ho
    • Korean Journal of Pharmacognosy
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    • v.35 no.2 s.137
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    • pp.157-163
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    • 2004
  • Twenty two polyphenols containing ten gallotannins, seven ellagitannins, two phenylpropanoids and three stilbenes isolated from the higher plants were tested inhibitory effects on melanogenesis in cultured B-16 mouse melanoma cell lines. Among the tested samples, 1-desgalloyleugeniin exhibited the most potent inhibitory effect on melanogenesis in cultured cell lines.

Isolation of Melanin Biosynthesis Inhibitory Compounds from the Seeds of Plantago asiatica L. (차전자(車前子)로부터 멜라닌 생성 억제물질의 분리)

  • Oh, Joon-Seok;Lee, Jong-Gu;Jung, Hee-Wook;Choi, Ji-Young;Choi, Eun-Hyang;Kim, Dong-Chun;Kim, Jeong-Ah;Son, Jong-Keun;Lee, Seung-Ho
    • Korean Journal of Pharmacognosy
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    • v.38 no.4
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    • pp.376-381
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    • 2007
  • Seven compounds were isolated from the MeOH extract of the seeds of Plantago asiatica L. and their structures were identified as ${\beta}-sitosterol$ (1), (24R)-6${\beta}$-hydroxy-24-ethyl-cholest-4-en-3-one (2), acteoside (3), geniposidic acid (4), 1-octen-3-ol 3-O-${\beta}$-D-xylopyranosyl$(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5), plantainoside D (6) and plantamajoside (7) on the spectroscopic analysis. Among them, $(24R)-6{\beta}$-hydroxy-24-ethyl-cholest-4-en-3-one (2) and 1-octen-3-ol 3-O-${\beta}$-D-xylopyranosyl ($1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5) were first isolated from this plant. Among them, geniposidic acid (4) showed the most potent inhibitory effect on melanogenesis, with inhibition rate of 41%.

Isolation of Melanogenesis Inhibitors from Cinnamomi Cortex (계피로부터 멜라닌 생성 억제 성분의 분리)

  • Jung, Hee-Wook;Choi, Ji-Young;Lee, Jong-Gu;Choi, Eun-Hyang;Oh, Joon-Seok;Kim, Dong-Chun;Kim, Jeong-Ah;Park, Seong-Hee;Son, Jong-Keun;Lee, Seung-Ho
    • Korean Journal of Pharmacognosy
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    • v.38 no.4
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    • pp.382-386
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    • 2007
  • Cinnamomi Cortex (Lauraceae), the dried bark of Cinnamomum cassia BLUME, has been used as traditional Chinese medicine for its stomachic, astringent, carminative, antispasmodic, antibacterial, antifungal properties. Four compounds were isolated from the MeOH extract of Cinnamomi Cortex, and their structures were identified as trans-cinnamic acid (1), ${\beta}-sitosterol$ (2), bis(2-methylheptyl)phthalate (3), coumarin (4) by comparison of their physical and spectral data with those reported in the literature. These compounds were tested melanogenesis inhibitory effect on B-16 mouse melanoma cell lines. Among them, trans-cinnamic acid (1) showed the most potent inhibitory effect on melanogenesis with $IC_{50}$ value of $13{\mu}g/ml$. Arbutin, positive control, exhibited an $IC_{50}$ value of $29{\mu}g/ml$.

Stringent Factor Regulates Antibiotics Production and Morphological Differentiation of Streptomyces clavuligerus

  • RYU , YONG-GU;JIN, WOOK;KIM, JIN-YOUNG;KIM, JAE-YOUNG;LEE, SANG-HEE;LEE, KYE-JOON
    • Journal of Microbiology and Biotechnology
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    • v.14 no.6
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    • pp.1170-1175
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    • 2004
  • The involvement of the relA and rsh genes in the morphological and physiological differentiation of Streptomyces clavuligerus was evaluated with the relA and rsh genes mutants. The morphological differentiation of S. clavuligerus was greatly affected by the disruption of the relA gene, but not very much by the disruption of the rsh gene. The altered morphological characteristics were completely restored by the complementation of the corresponding disrupted genes. Thus, it was apparent that the mycelial morphology and clavulanic acid production were severely affected by the disruption of the relA gene. Production of clavulanic acid in the submerged batch culture and glycerol-limited chemostat showed that production was inversely related to the specific growth rate in the wild-type strain. However, the production of clavulanic acid in the ${\Delta}relA$ and ${\Delta}rsh$ null mutants was completely abolished. Therefore, it seems plausible that the stringent response of S. clavuligerus to starvation for amino acids is governed mainly by ReIA, rather than Rsh, and that the (p)ppGpp synthesized immediately after the depletion of amino acids triggers the initiation of pathways for both morphological and physiological differentiation in this species.

Watershed Scale Management Techniques of the Pollutants from Small Scale Livestock Ranches - Buffer Zone Selection for Natural Purification - (농촌 소유역 축산폐수의 유역관리기법 개발 - 자연정화처리를 위한 완충대 적지분석 -)

  • Kim, Seong-Joon;Lee, Nam-Ho;Yoon, Kwang-Sik;Hong, Seong-Gu;Lee, Yun-Ah
    • Journal of Korean Society of Rural Planning
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    • v.6 no.2 s.12
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    • pp.43-49
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    • 2000
  • Buffer zone selection technique for natural purification of livestock wastewater within a small agricultural watershed was developed using Geographic Information Systems. The technique was applied to $4.12\;km^2$ watershed located in Gosan-myun, Ansung-gun which have 20 livestock farmhouses. As a necessary data for selecting process, feedlot site map, digital Elevation Model (DEM), stream network, soil and land use map were prepared. By using these data, wastewater moving-path tracing program from each feedlot to the stream was developed to get the basic topographic factors; average slope through the paths, distance to the nearest stream and watershed outlet. To identify the vulnerable feedlots for storm event, the grid-based storm runoff model (Kim, 1998; Kim et al., 1998) was adopted. The result helps to narrow down the suitable area of buffer zone, and finally by using subjective but persuasive conditions related to elevation, slope and land use, the suitable buffer zones were selected.

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The Charecteristics of Superposed Discharge Type Ozonizing System Considering the Change of Temperature of. the Supplied Gas (원료가스의 온도변화를 고려한 중첩방전형 오존발생장치의 특성)

  • Lee, Sang-Keun;Song, Hyun-Jig;Chun, Byung-Joon;Kim, Yeong-Hun;Kim, Sang-Gu;Park, Won-Zoo;Lee, Kwang-Sik
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1705-1707
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    • 1998
  • In this paper, a superposed discharge type ozonizer was designed and manufactured. The ozonizer is equipped with three electrodes : central electrode, internal electrode and external electrode, and it consists of two gaps. The ozone is generated by superposing silent discharge, which are respectively generated betweens two gaps. This paper describes the following two characteristics : (1) 'the characteristics of discharge with variation with output voltage of AC High Voltage source, quantity of the supplied gas and discharge voltage (2) the characteristics of ozone discharge power, temperature of the supplied gas.

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A 0.55" PDLC-LCoS Micro-display for Mobile Projectors

  • Do, Yun-Seon;Yang, Kee-Jeong;Sung, Shi-Joon;Kim, Jung-Ho;Lee, Gwang-Jun;Lee, Yong-Hwan;Chung, Hoon-Ju;Roh, Chang-Gu;Choi, Byeong-Dae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1527-1530
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    • 2009
  • A LCoS micro-display using polymer dispersed liquid crystals (PDLCs) for light switching layer was fabricated. The Si backplane of SVGA ($800{\times}600$) with a pixel size of $14{\times}14mm^2$ was prepared by a $0.35{\mu}m$ 18V CMOS process. PDLCs were filled in the gap between backplane and ITO glass by conventional vacuum filling method. The prepared panels were driven by a field sequential color (FSC) scheme at the frequency of 180Hz and were successful in modulating LED lights to show projection images. The preparation and performance of PDLC-LCoS are presented.

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Analysis of surface displacement of Gwangsan-gu using PS-InSAR technique (PS-InSAR기법을 이용한 광산구 지표 변위 분석)

  • Lee, Won-Eung;Yoon, Hong-Sik;Youm, Min-Kyo;Lee, Joon-Min
    • Proceedings of the Korean Society of Disaster Information Conference
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    • 2017.11a
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    • pp.369-371
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    • 2017
  • 지반침하는 열차 탈선과 같은 대형재난을 야기할 수 있다. 그러므로 지반침하를 사전에 파악하기 위한 다양한 연구가 진행 중이다. 최근 광범위한 지역의 지표변위를 경제적으로 분석할 수 있는 InSAR(nterferometric SAR)기법을 이용한 연구가 활발히 진행되고 있다. InSAR 기법 중 PS-InSAR(Permanent Scatterer Interferometric SAR)기법이란 SAR영상에서 긴밀도가 높은 고정산란체(PS:Permanent scatterer)를 이용하여 지반침하를 분석하는 기법으로 다른 InSAR 기법에 비해 대기에 의해 발생하는 오차가 적으며, 보다 정확한 지표변위량을 도출할 수 있다. 또한 장기간에 걸친 시계열적 지표 변위 분석에 용이하다. 본 논문에서는 독일의 Terra SAR-X 위성 영상을 이용하여, 광주광산구의 지표변위를 분석하였다. 연구지역인 광주 광산구는 대표적인 연약지반인 평야지역에 위치해 있으며, 실제로 2015년 한국시설안전공단의 발표에 의하면 6곳의 지반탐사 필요 의심지역이 존재할 만큼 지반이 불안정한 지역이다. 연구 결과 광주 광산구 8mm/year로 지반이 침하되고 있음을 알 수 있었다. 이에 광주 광산구 일대의 지반침하 대비를 위해 다양한 노력들이 필요할 것으로 사료된다.

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Guillain-Barré Syndrome after Lung Transplantation in the Immediate Postoperative Period: Case Report

  • Gu, Byung Mo;Ko, Ho Hyun;Lee, Hong Kyu;Ra, Yong Joon;Lee, Hee Sung;Kim, Hyoung Soo
    • Journal of Chest Surgery
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    • v.54 no.5
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    • pp.396-399
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    • 2021
  • A 58-year-old man, incapable of maintaining oxygen saturation with mechanical ventilation, was admitted to our hospital for veno-venous extracorporeal membrane oxygenation (ECMO) treatment. He was diagnosed with acute respiratory distress syndrome (ARDS) due to influenza A pneumonia. His condition stabilized with antibiotics and steroid administration, but weaning from ECMO failed due to post-infectious pulmonary sequelae. On day 84 after admission, he underwent bilateral lung transplantation. In the postoperative phase, he did not regain consciousness even after discontinuation of sedatives for 3 days. However, spontaneous pupillary reflex and eye movements were preserved, while communication and upper and lower limb movements were affected. The nerve conduction study was diagnostic of Guillain-Barré syndrome. He was managed with intravenous immunoglobulins and plasmapheresis. Mild recovery of the facial muscles was seen, but he died 24 days post-surgery due to progressive ARDS and sepsis.

The Thought of Che-Qi-Jung concerned with Phenomenon of Stress (STRESS 현상(現象)과 관련(關聯)된 제기증(諸氣證)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Koh, Tae Joon;Lee, Sang Ryong
    • Journal of Haehwa Medicine
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    • v.8 no.2
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    • pp.317-327
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    • 2000
  • Through the study about Che-Qi-Jung(諸氣證) concerned with phenomenon of stress, we concluded as fallow. 1. Stressors are recognized three parts, internal cause, external cause, non-interexternal cause, in the oriental medicine. And the reaction of the body about stressors, was expressed change of Qi(氣). 2. The vascular system and autonomic nervous system are tensed or relexed. Because the etiology of Yuk-Em(六淫), Chil-Jeong(七情) make lose up and down, in and out, circulation of Gi(氣). The symtom caused with stress are explained, divided into Chil-Qi(七氣), Gu-Qi(九氣), Joong-Qi(中氣), Qi-Tong(氣痛), Qi-Yuk(氣逆), Qi-Wool(氣鬱). 3. The symtom of Chil-Qi is recognized into psycholoQical stress and Mae-Haek-Qi(梅核氣). The symtom of Gu-Qi is composed of Chil-Qi and Han(寒), Youl(熱), Ro(勞). 4. The symtoms of Qi-Yuk and Joong-Qi are caused by the ascent of Hwa-Qi(火氣). And Hwa-Qi is made by rage and depression. Qi-Yuk is chronic symtom that the ascent of Hwa-Qi is made by out of function in up and down mechanism of Qi. Joong-Qi is acute symtom that patholoQical state of Qi-Yuk take place for a while by sudden psycholoQical shock. 5. The symtom of Qi-Wool is loss of funtion made by depressed state in physioloQical mechanism, and Qi-Wool is observed in depressive psychosis and hypochondriasis and psychogenic. 6. The symtom of Qi-Tong is the pain caused by interference of circulation of Qi-Hyul(氣血). PsycholoQical stimulation such as rage and depression, tense autonomic nervous system. This make convulsion in gastro-intestine or vascular circuluation or abdominal muscles, and the pain is caused by convulsion.

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