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Study on IL -8 Expression in Peripheral Blood Monocytes (말초 혈액 단핵구에서 IL-8 발현에 관한 연구)

  • Kim, Jae-Yeol;Lee, Jae-Cheol;Kang, Min-Jong;Park, Jae-Seok;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Lee, Jae-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.5
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    • pp.703-712
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    • 1995
  • Background: Peripheral blood monocytes are important immune effector cells that play a fundamental role in cellular immunity. In addition to their antigen-presenting and phagocytic activities, monocytes/macrophage produce a vast array of regulatory and chemotactic cytokines. Interleukin-8(IL-8), a potent neutrophil-activating and chemotactic peptide, is produced in large quantities by mononuclear phagocytes and may be an important mediator of local and systemic inflammation. Overexpression by IL-8 of such inflammation may be an important step of tissue injury frequently seen in inflammatory reaction. So it could be hypothesized that the agents which block the production of IL-8 can decrease the inflammatory reaction and tissue injury. To evaluate this, we described the effect of Dexamethasone, $PGE_2$, Indomethacin and Interferon-$\gamma$(IFN-$\gamma$) on IL-8 mRNA and protein expression from LPS-stimulated human peripheral blood monocytes(PBMC). Method: PBMC was isolated from healthy volunteers. To evaluate the effect of Dexamethasone, $PGE_2$ & Indomethacin, these drug were treated for 1 hour before and after LPS stimulation and IFN-$\gamma$ was only treated I hour before the LPS stimulation. Northern blot analysis for IL-8 mRNA and ELISA for immunoreactive IL-8 protein in culture supernatant were performed. We repeated above experiment three times for Northern blot analysis and two times for ELISA and got the same result. Results: 1) Pre- and post-treatment of Dexamethasone suppressed both the LPS stimulated IL-8 mRNA expression and IL-8 protein release in PBMC. 2) IFN-$\gamma$ pre-treatment suppressed the IL-8 mRNA expression and IL-8 protein release in unstimulated cells. 3) In LPS stimulated cells, IFN-$\gamma$ suppressed the IL-8 mRNA expression but IL-8 protein release suppression was not observed. 4) $PGE_2$ and Indomethacin exert no effect on the LPS-stimulated IL-8 mRNA and protein expression in concentration used in this experiment ($PGE_2;10^{-6}M$, Indomethacin; $10{\mu}M$). Conclusion: One of the mechanism of antiinflammatory action of Dexamethasone can be explained by the suppressing effect of IL-8 production in some extent and by this antiinflammatory effect, dexamethasone can be used to suppress local and systemic inflammation mediated by IL-8.

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Effect of specimen preparation method on the microtensile bond strength of veneering ceramic to zirconia (시편 제작 방법이 지르코니아 코어와 비니어링 세라믹의 미세 인장결합강도에 미치는 영향)

  • Kim, Ki-Yeon;Yeo, In-Sung;Kim, Sung-Hun;Han, Jung-Suk;Lee, Jai-Bong;Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.2
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    • pp.114-119
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    • 2011
  • The aim of this study was to investigate effect of specimen preparation method on the microtensile bond strength of veneering ceramic to zirconia core. Materials and methods: Cylindrical Lava zirconia block (3M ESPE, Seefeld, Germany) was cut into discs using a diamond disc. After sintering, the core specimens were placed in an adjustable mold and veneered with Lava ceram (3M ESPE, Seefeld, Germany). The disc shaped specimen of group 1 was cut into microbars ($1{\times}1{\times}7\;mm^3$) using a low speed diamond disc under water cooling (n = 15). The specimen of group 2 was cut into microbars ($1.2{\times}1.2{\times}7\;mm^3$) in the same way. Whereafter the microbars were trimmed ($1{\times}1{\times}7\;mm^3$) using a thick diamond disc under water cooling (n = 15). The microtensile bond strength was tested in a microtensile tester (Instron 8848, $Instron^{(R)}$ Co., Norwood, USA). Fractured microtensile specimens were analyzed under a stereomicroscope (MZ6, Leica Microsystems GmbH, Wetzlar, Germany) at magnification ${\times}30$. Results: The microtensile bond strength of group 1 ($28.8{\pm}7.0\;MPa$) was significantly higher than group 2 ($11.0{\pm}33\;MPa$) (P=.00). Conclusion: It appears advisable to avoid the trimming action, especially high strength ceramic specimens.

A Study on the Smog Reduction Strategies in China (중국의 스모그 저감정책에 대한 고찰)

  • Jeon, So Hyeon;Kim, Yong Pyo
    • Particle and aerosol research
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    • v.11 no.3
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    • pp.63-75
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    • 2015
  • Atmospheric environment in Korea is influenced by outside, especially China. The concentrations of air pollutants in China have showed decreasing trends since 2000. However, these concentration levels in China are still higher than other developed countries. The Chinese Government has tried several measures to control the air pollution. In this study, the details of the amendments and smog reduction strategies in China, especially for Beijing are reviewed and the strategies for Korean side to promote cooperation in Northeast Asia are suggested and discussed. The Chinese State Council amended the Environmental Protection Provisions and Clean Air Act and announced The Action Plan for Air Pollution Control (2013-2017), focusing on three key regions, Beijing-Tianjin-Hebei area (Jing-Jin-Ji), Yangtze River Delta (YRD) and Pearl River Delta (PRD). These policy actions and plan are mainly for the reducing coal usage and emissions from vehicles. It is suggested that, Korea should actively promote multi-national cooperation in the region to take an initiative role in environmental areas.

EFFECTS OF SUBINHIBITORY CONCENTRATIONS OF ANTIMICROBIAL AGENTS ON CELL SURFACE PROPERTIES AND VIRULENCE FACTORS OF MUTANS STREPTOCOCCI (아저해농도(亞沮害濃度)의 항균물질이 mutans streptococci의 세포표면성질과 독력인자에 미치는 영향)

  • Kim, Young-Jae;Hahn, Se-Hyun;Lee, Sang-Hoon;Jang, Ki-Taeg;Kim, Chol-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.4
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    • pp.605-616
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    • 2004
  • Subinhibitory concentrations (sub-MICs) refer to concentrations below minimum inhibitory concentrations (MICs). The antimicrobial agents may be present at relatively high concentration, at least higher than bacterial MIC and thereafter be deserted off a surface and function at sub-MICs, perhaps by interfering with bacterial metabolism. Consequently, the aim of this study was to determine the effects of growth, in the presence of sub-MICs of antimicrobial agents, on the cell surface properties and virulence factors of mutans streptococci and to investigate the efficacy of a chemical approach in vitro. Streptococcus mutans Ingbritt and Streptococcus sobrinus 6715-7 were used. Eight antimicrobial agents (Sanguinaria extract;SG, Chlorhexidine digluconate;CHX, Fluoride;F, Propolis;PP, Hydrogen peroxide;HP, Triclosan;TC, Sodium dodecyl sulfate;SDS Cetylpyridinium chloride; CC) were diluted serially in broth to determine MICs and to compare the growth rate, acid production, hydrophobicity, adhesion activity to saliva coated hydroxyapatite, glucan synthesis and cellular aggregation of experiment groups (in the presence of sub-MICs) with those of control (in the absence of antimicrobial agents). Sub-MICs of antimicrobial agents affected the growth of cells, hydrophobicity, and adhesion of bacteria to saliva coated hydroxyapatite and glucan synthesis. They also resulted in a significant reduction in pH after 12 hours (p<0.05). By cells pretreated with proteinase K, either the aggregation induced by antimicrobial agents was completely inhibited or the aggregation titers were markedly increased. According to the results of the present study, each antimicrobial agent at sub-MICs could affect similar as its known action mechanism and could continually inhibit cariogenic bacteria at such concentrations. Thus, the use of these antimicrobial agents would be one of the effective methods to prevent dental caries.

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A Study on Floating Offshore LNG Bunkering System and its Economic Analysis (해상부유식 LNG 벙커링 시스템 R&D사업의 경제성 분석)

  • Seo, Sunyae;Cho, Sungwoo
    • Journal of Korea Port Economic Association
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    • v.30 no.4
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    • pp.69-89
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    • 2014
  • The business performance of port industry is steadily getting worse due to international environmental regulation. The port industry should be prepared according to ambient condition change. IMO(International Maritime Organization) is tightening up environmental regulation of vessel and maritime industry field. ECA(Emission Control Area), starting with the Baltic, has initialized and has been expanded. Korea must strengthen the control of vessel in accordance with IMO's restriction, if Korea is designated as emission control area. These situations cause the expansion of LNG-fuelled ships. Add to the larger trend of ships, Korean government should be done a preemptive action against LNG bunkering industry. This study proposes the concept of floating offshore LNG bunkering system and is conducted its economic feasibility evaluation based on empirical analysis. We examine the theoretical foundation and basic information via "A Planning Study on the Engineering Development of Floating Offshore LNG Bunkering Terminal" in 2013 and we evaluate the business potential by using the report above mentioned. The results of this study are as follows. The values of B/C analysis are between 0.679 and 2.516 depending on market share and R&D contributiveness. In case of 10.9%(market share), if market share are 50% and 60%, the value of B/C analysis are 0.697 and 0.837 respectively. Except in two cases, all remaining values are over 1.0. Moreover, the research is conducted sensitivity analysis to remove the project uncertainty. In order to maintain economical validity, a project manager have to establish business strategies which are not to cause increase of expense and sustain market share and R&D contributiveness in the scenario with normal levels.

Effect of Ginseng Saponin on LDL Receptor Biosynthesis (인삼사포닌의 저밀도지질단백질(LDL)수용체에 미치는 영향)

  • Joo Chung No;Lee Hee Bong;Lee Yong Woo;Kang In Chul
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.47-54
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    • 1988
  • Cholesterol a component of all eucaryotic plasma membranes. is essential for the growth and viability of cells in higher organisms. However. too much cholesterol can be lethal because of atherosclerosis resulting from the deposition of cholesterol ester plaques. It was attempted in this study to understand the preventive effect of ginseng saponin. one of the major components of the roots of Panax ginseng C.A. Meyer. against hypercholesterolemia induced by high cholesterol diet. $^{125}I-LDL$ was injected intravenously to rabbits and rats. which were fed a high cholesterol diet with and/or without ginseng saponin for 12 days. The disappearance of the radioactivity occurred faster in the test group than the control. The effect of saponin fraction from Panax ginseng C.A. Meyer and the purified ginsenosilks. $Rb_1,\;Rb_2,\;Re\;and\;Rg_1,$ on LDL receptor biosynthesis in high cholesterol fed rat has been investigated. Analysis of LDL receptors from various organs such as liver. kidney. adrenal cortex and testis showed that the population of LDL receptors of test group significantly higher than that of the control. It was also found that liver homogenate containing ginsenosides $(10^{-3}-10^{-4}\%)$ stimulated the biosynthesis of bile acid form cholesterol. From the above results. it seemed that ginsenosides lower the cholesterol level by stimulating cholesterol metabolism. which result in the suppression of the inhibitory action of cholesterol on LDL receptor biosynthesis.

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Effects of Mulberry Leaves Powder on Lipid Metabolism in High Cholesterol-Fed Rats (뽕잎분말이 고콜레스테롤 식이 투여 흰쥐의 지질대사에 미친 영향)

  • Kim, Ae-Jung;Kim, Sun-Yeou;Choi, Mi-Kyeong;Kim, Myung-Hwan;Han, Myung-Ryun;Chung, Kun-Sub
    • Korean Journal of Food Science and Technology
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    • v.37 no.4
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    • pp.636-641
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    • 2005
  • Mulberry leaves, high in dietary fiber and some nutritional materials, are thought to have hypocholesterolemic effect. Therefore, effect of mulberry leaf powder on serum lipid profiles were studied using rats with diet-induced hypercholesterolemia. Male Sprague-Dawley rats were fed AIN-93 diet (control group), and diets containing high-cholesterol and 0% mulberry leaves powder, high-cholesterol and 5% mulberry leaves powder, and high-cholesterol and 10% mulberry leaves powder for 4 weeks. Hypercholesterolemia was induced by adding 1% cholesterol and 0.5% cholic acid to all diets except in control group. Although no differences were observed in food intake and initial body weight among groups, mulberry leaf treatment resulted in significant decreases in food efficiency ratio and body weight gain. Mulberry leaf treatment decreased serum lipid profiles, atherogenic index, cardiac risk factor, low density lipoprotein cholesterol ratio, serum aspartate transaminase, and liver lipid levels. High density lipoprotein cholesterol, total cholesterol, serum HDL-cholesterol, and fecal lipid levels increased, suggesting mulberry leaves could improve hyperlipidemia and liver action, thereby proventing cardiovascular disease.

Studies on the Changes of Lipids during Soybean Koji Preparation for Daenjang Fermentation in Model System (된장 발효(醱酵) 중 콩 Koji 제조(製造)과정에 있어서 지질성분(脂質成分)의 변화(變化)에 관한 연구(硏究))

  • Lee, Sook-Hee;Cheigh, Hong-Sik;Kim, Chang-Sik
    • Korean Journal of Food Science and Technology
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    • v.14 no.4
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    • pp.375-381
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    • 1982
  • The studies are conducted on the changes of soybean lipids in terms of physicochemical characteristics, lipid classess and fatty acid composition during the fermentation process of soybean Koji preparation for daenjang (soybean paste) in a model system using cooked soybean inoculated by Aspergillus oryzae. The total lipids contents were increased during soybean Koji preparation, generally iodine values decreased but acid values increased. Total lipids of soybean Koji consisted of about 90.6% neutral lipids, 7.6% phospholipids and 1.8%, glycolipids indicating that phospholipids contents of soybean Koji was increased when compared to those of cooked soybean. The major components of nonpolar lipids in soybean Koji were free fatty acids(39.6%) and triglycerids(29.2%). Free fatty acids increased as the triglycerides decreased during soybean Koji preparation by the hydrolysis of lipase action. The major components of polar lipids in soybean Koji were phosphatidyl choline and phosphatidyl ethanolamine. Differences were observed in the composition of the polar lipids of cooked soybean and soybean Koji. A little changes also occurred in fatty acid compositions of total lipids, triglycerides and free fatty acids fractions in soybean Koji preparation. Especially a considerable increase of linoleic acid in free fatty acid fraction was observed in soybean Koji.

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Studies on the Preservation of Soy Sauce -Part I. The Periodical Change of Chemical Composition and Microflora- (제품 간장의 보존에 관한 연구 -제1보 일반성분 및 미생물의 경시적 변화-)

  • Lee, Taik-Soo;Chu, Young-Ha;Shin, Bo-Kyu;Yu, Ju-Hyun
    • Korean Journal of Food Science and Technology
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    • v.7 no.4
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    • pp.200-207
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    • 1975
  • This experiment was carried out to investigate the chemical composition and microflora of soy sauce during storage under the different temperature. The results obtained are as follows. (1) Total nitrogen, color density, specific gravity and sodium chloride concentration of soy sauce showed a increasing tendency in the progress of storage period. Open-storage state at $30^{\circ}C\;and\;15^{\circ}C$ were responsible to the increase of components as compare with close-storage state at $5^{\circ}C$. (2) pH and buffer action were not almost changed during the storage. (3) Alcohol and sugar contents of soy sauce showed a decreasing tendency in the process of storage period, especially in the case of open state alcohol being almost disappeared within 11 months in all groups. (4) The number of common bacteria in one ml of soy sauce were counted as $96{\times}10^4$ before pasteurization and $10^3$ after pasteurization. The osmophilic bacteria was counted as $38{\times}10^4$, $10^2$ after pasteurization. (5) The spore number of mold in one ml of soy sauce were counted $32{\times}10^7$ before pasteurization, 58 after pasteurization and 10 to $10^2$ in the progress of storage period. (6) The bacteria number of soy sauce were somewhat decreased with the passing, of the time. The group of high temperature and open state were more notable than low temperature and close state.

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Apoptotic Cell Death by Pectenotoxin-2 in p53-Deficient Human Hepatocellular Carcinoma Cells (종양억제유전자 p53 결손 인체간암세포에서 Pectenotoxin-2에 의한 Apoptosis 유도)

  • Shin, Dong-Yeok;Kim, Gi-Young;Choi, Byung-Tae;Kang, Ho-Sung;Jung, Jee-H.;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1447-1451
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    • 2007
  • Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.