• Title/Summary/Keyword: rate dependent

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Ectopic Expression of Wild Rice OgGRP Gene Encoding a Glycine Rich Cell Wall Protein Confers Resistance to Botrytis cinerea Pathogen on Arabidopsis

  • Jeon, Eun-Hee;Chung, Eun-Sook;Lee, Hye-Young;Pak, Jung-Hun;Kim, Hye-Jeong;Lee, Jai-Heon;Moon, Byung-Ju;Jeung, Ji-Ung;Shin, Sang-Hyun;Chung, Young-Soo
    • The Plant Pathology Journal
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    • v.25 no.2
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    • pp.193-198
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    • 2009
  • A full-length cDNA of OgGRP gene encoding a glycinerich cell wall protein was isolated from wild rice (Oryza grandiglumis). Deduced amino acid sequences of OgGRP are composed of 148 amino acids (16.3 kDa), and show 85.9% homology with Osgrp-2 (Oryza sativa). RT-PCR analysis showed that RNA expression of OgGRP was regulated by defense-related signaling chemicals, such as cantharidin, endothall, jasmonic acid, wounding, or yeast extract treatment. In relation to pathogen stress, the function of OgGRP was analyzed in OgGRP over-expressing Arabidopsis thaliana. Overexpression of OgGRP in Arabidopsis contributed to moderate resistance against fungal pathogen, Botrytis cinerea, by lowering disease rate and necrosis size. In the analysis of the transgenic Arabidopsis lines to check the change of gene expression profile, induction of PR1, PR5 and PDF1.2 was confirmed. The induction seemed to be caused by the interaction of ectopic expression of OgGRP with SA-and JA-dependent signaling pathways.

Study on rheological characterization of Gellan gum Produced by Pseudomonas elodea -Comparative Studies on Rheological Characterization of Gellan gum and Agar- (Pseudomonas elodea에 의해서 생산된 Gellan gum과 Agar의 rheology 특성 비교연구)

  • 권혜숙;구성자
    • Korean journal of food and cookery science
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    • v.4 no.1
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    • pp.17-26
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    • 1988
  • The polysaccharide produced by pseudomonas elodea, Gellan gum, was rheologically characterized, compared with agar. Rheological properties were determined from the change in the value of intrinsic viscosity with the pH and salt concentration. At the range of pH 2∼ll and salt 0∼0.16M KC1, the intrinsic viscosity of Gellan gum ranged from 8.8 to 21.2dl/g and agar ranged from 1.97 to 11.46d1/g. In the absence of salt, the intrinsic viscosity of Gellan gum increased as the pH of solution increased up to neutral pH then decreased slightly at alkaline pH, whearas the intrinsic viscosity of agar increased as the pH of solution increased up to pH 9 then decreased slightly. Intrinsic viscosity of Gellan gum and agar decreased with an increase in salt concentration. The chain stiffness parameter for the Gellan gum was 0.033. The overlap parameter of Gellan gum and agar were 0.047g/dl and 0.087g/dl, respectively. Gellan gum and agar were shear rate dependent or pseudoplastic. The yield stress and proportionality constant of Gellan gum increased slightly as the concentration increase, on the other hand, the shear index of Gellan gum showed a maximum at 0.75g/dl and gradually decreased as the concentration increase. The apparent viscosity of Gellan gum and agar decreased as the temperature increase. A lower concentration of the divalent cations calcium and magnesium is required to obtain maximum gel strength than for the monovalent cations sodium and potassium.

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Mechanism of Chemoprevention against Colon Cancer Cells Using Combined Gelam Honey and Ginger Extract via mTOR and Wnt/β-catenin Pathways

  • Wee, Lee Heng;Morad, Noor Azian;Aan, Goon Jo;Makpol, Suzana;Ngah, Wan Zurinah Wan;Yusof, Yasmin Anum Mohd
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6549-6556
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    • 2015
  • The PI3K-Akt-mTOR, $Wnt/{\beta}$-catenin and apoptosis signaling pathways have been shown to be involved in genesis of colorectal cancer (CRC). The aim of this study was to elucidate whether combination of Gelam honey and ginger might have chemopreventive properties in HT29 colon cancer cells by modulating the mTOR, $Wnt/{\beta}$-catenin and apoptosis signaling pathways. Treatment with Gelam honey and ginger reduced the viability of the HT29 cells dose dependently with $IC_{50}$ values of 88 mg/ml and 2.15 mg/ml respectively, their while the combined treatment of 2 mg/ml of ginger with 31 mg/ml of Gelam honey inhibited growth of most HT29 cells. Gelam honey, ginger and combination induced apoptosis in a dose dependent manner with the combined treatment exhibiting the highest apoptosis rate. The combined treatment downregulated the gene expressions of Akt, mTOR, Raptor, Rictor, ${\beta}$-catenin, $Gsk3{\beta}$, Tcf4 and cyclin D1 while cytochrome C and caspase 3 genes were shown to be upregulated. In conclusion, the combination of Gelam honey and ginger may serve as a potential therapy in the treatment of colorectal cancer through inhibiton of mTOR, $Wnt/{\beta}$ catenin signaling pathways and induction of apoptosis pathway.

Effects of Emodin Extracted from Chinese Herbs on Proliferation of Non-small Cell Lung Cancer and Underlying Mechanisms

  • He, Lin;Bi, Juan-Juan;Guo, Qian;Yu, Yin;Ye, Xiu-Feng
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1505-1510
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    • 2012
  • To aim of this was to observe emodin-mediated cytotoxicity and its influence on Rad51 and ERCC1 expressionin non-small cell lung cancer (NSCLC). NSCLC cells were cultured in vitro with emodin at various concentrations (0, 25, 50, 75 and $100\;{\mu}mol/L$) for 48h and the proliferation inhibition rate was determined by the MTT method. Then, NSCLC were treated with emodin (SK-MES-1 $40\;{\mu}mol/L$, A549 $70\;{\mu}mol/L$) or $20\;{\mu}mol/L$ U0126 (an ERK inhibitor) for 48 h, or with various concentrations of emodin for 48 h and the protein and mRNA expressions of ERCC1 and Rad51 were determined by RT-PCR and Western blot assay, respectively. Emodin exerted a suppressive effect on the proliferation of NSCLC in a concentration dependent manner. Protein and mRNA expression of ERCC1 and Rad51 was also significantly decreased with the dose. Vacuolar degeneration was observed in A549 and SK-MES-1 cell lines after emodin treatment by transmission electron microscopy. Emodin may thus inhibited cell proliferation in NSCLC cells by downregulation ERCC1 and Rad51.

A Novel All-trans Retinoid Acid Derivative N-(3-trifluoromethyl-phenyl)-Retinamide Inhibits Lung Adenocarcinoma A549 Cell Migration through Down-regulating Expression of Myosin Light Chain Kinase

  • Fan, Ting-Ting;Cheng, Ying;Wang, Yin-Feng;Gui, Shu-Yu;Chen, Fei-Hu;Zhou, Qing;Wang, Yuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7687-7692
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    • 2014
  • Aim: To observe the effects of a novel all-trans retinoid acid (ATRA) derivative, N-(3-trifluoromethyl-phenyl)-retinamide (ATPR), on lung adenocarcinoma A549 cells and to explore the potential mechanism of ATPR inhibiting of A549 cell migration. Materials and Methods: The cytotoxicity of ATRA and ATPR on A549 cells was assessed using MTT assay. Wound healing assays were used to analyze the influences of ATRA, ATPR, ML-7 (a highly selective inhibitor of myosin light chain kinase (MLCK)), PMA (an activator of MAPKs) and PD98059 (a selective inhibitor of ERK1/2) on the migration of A549 cells. Expression of MLCK and phosphorylation of myosin light chain (MLC) were assessed by Western blotting. Results: ATRA and ATPR inhibited the proliferation of A549 cells in a dose- and time-dependent manner, and the effect of ATPR was much more remarkable compared with ATRA. Relative migration rate and migration distance of A549 cells both decreased significantly after treatment with ATPR or ML-7. The effect on cell migration of PD98059 combining ATPR treatment was more notable than that of ATPR alone. Moreover, compared with control groups, the expression levels of MLCK and phosphorylated MLC in A549 cells were both clearly reduced in ATRA and ATPR groups. Conclusions: ATPR could suppress the migration and invasion of A549 cells, and the mechanism might be concerned with down-regulating the expression of MLCK in the ERK-MAPK signaling pathway, pointing to therapeutic prospects in lung cancer.

Kinetic Studies on the Oxidation of Oxalate Complex of Oxomolybdenum (V) of Hydrogen Chromate Ion (수소크롬산 (VI) 이온에 의한 몰리브덴 (V) 의 옥살산착물의 산화반응)

  • Chang-Yong Kwon;Chang-Su Kim
    • Journal of the Korean Chemical Society
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    • v.30 no.2
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    • pp.231-236
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    • 1986
  • Oxidation of $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$ with hydrogen chromate yields the molybdenum (VI) complex, $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$. Stoichiometry for the reaction of $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$ with hydrogen chromate are expressed as ${3Mo_2}^V+2Cr^{VI}\;{\rightleftharpoons}\;{3Mo_2}_{VI}+2Cr^{III}$. Observed rate constants are dependent on $[H+]^2$. The kinetic data are consistent with a mechanism in which three successive single-electron steps convert $Cr^{VI}$to $Cr^{III}$ by way of intermediate Cr^V$ and $Cr^{IV}$. Mechanism of the reaction are presented and discussed.

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The Repair of MNNG-Induced DNA Damage and Its Relation to Chromosome Aberrations in Mammalian Cells (MNNG에 의한 DNA 회복합성과 염색체 이상과의 연관성에 관한 연구)

  • Kim, Choon-Kwang;Lee, Chun-Bok
    • The Korean Journal of Zoology
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    • v.23 no.3
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    • pp.115-123
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    • 1980
  • The rates of escision repair at various doses and times after MNNG treatment in CHO cells were compared with the frequencies of chromosome aberrations to determine a possible relation between there two types of biological phenomena, and the results obtained were as follows: 1. the MNNG-induced excision repair was dose-dependent in te ranges between $0.5 \\times 10^-5$M. The maximum rate of excision repair was occurred in the cells soon after the treatment. The rates were then gradually decreased and appeared about 66% of 0 hour at 24 hours. 2. The rates of chromosome aberrations induced by MNNG was the highest at 6 hours, in which majority were chromatid deletions. The rates of chromatid deletions decreased, whereas chromatid exchanges increased with time, resulting is about equal rates at 24 hours after treatment. 3. The rates of excision repair at different times after MNNG treatment were roughly related to the total breaks per cell. The rates, however, did not show any relation to either chromatid exchanges or deletions. These results may suggest that excision repair may not be directly related to chromosome aberrations in MNNG treated CHO cells.

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Effects of Ramp Slope and Height on Usability and Physiology during Wheelchair Driving (경사로의 기울기와 높이에 따른 휠체어 사용자의 사용성 및 생리적 특성 분석)

  • Kim, Chung-Sik;Lee, Dong-Hun;Lee, Jee-Hea;Kwon, Sung-Hyuk;Chung, Min-K.
    • Journal of the Ergonomics Society of Korea
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    • v.29 no.4
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    • pp.681-686
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    • 2010
  • Although the height of a ramp is an important design element, it has not been considered in prior studies. Therefore, in this study, the ramp slope and height are considered as independent variables. To analyze the effects of the slope and height, five levels of slope (1:6, 1:8, 1:10, 1:12 and 1:14) and three levels of height (15cm, 30cm and 45cm) are considered. For the dependent variables, the total time, velocity and perceived discomfort were considered as usability measures, pulse rate changes and EMG signals of four related muscles (extensor carpi radialis, triceps brachii, anterior deltoid and posterior deltoid) were considered as physiology measures. As a result, differences among usability and physiological characteristic for the five slopes increased as the height increased. Additionally, slope effects were minor when the height was low (15cm). Almost domestic/international regulations and guidelines related to ramp recommended 1:12 slope for the ramp design, however, there was no significant difference between 1:10 and 1:12 according to result of this study. In addition, slope effects were minor at a low height; thus, a slope of 1:8 can be recommended if the installation space for a gentler ramp is not sufficient.

Cardiovascular Effects of Novel Potassium Channel Opener SKP-450 and SKP-818 in Isolated Rat Heart and Aorta (신규 합성 $K_{ATP}$ 통로 개방제인 SKP-450과 대사체 SKP-818의 흰쥐 적출 심장 및 대동맥에 대한 작용)

  • Jung, Yi-Sook;Moon, Chang-Hyun;Yoo, Sung-Eun;Shin, Hwa-Sup
    • YAKHAK HOEJI
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    • v.41 no.2
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    • pp.241-246
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    • 1997
  • The effect of potassium channel openers, SKP-450, SKP-818 and lemakalim have been compared in rat heart and aorta. In rat isolated heart, SKP-450 had a greater negative inotrop ic effect than lemakalim and KR-30818 against left ventricular developed pressure (LVDP) and double product of heart rate and LVDP (DP). In addition, SKP-450 had a greater effect than lemakalim and KR-30818 in increasing coronary flow, indicating a more potent vasodilating effect in coronary artery. Negative inotropic effect and coronary vasodilating effect of SKP-450 and SEP-818 were significantly reduced by 10 min-perfusion with $10^{-6}M$ glyburide, a selective blocker of ATP-sensitive potassium channel. In rat aorta, SKP-30450 and SKP-30818 as well as lemakalim induced powerful concentration-dependent relaxations against norepinephrinc-induced tone ($EC_{50},\;{\mu}M$ : SKP-30450, $0.107{\pm}0.009$; SKP-30818, $0.476{\pm}0.022$ ; lemakalim, $0.565{\pm}0.039$ ). These relaxant effects were significantly reduced by pretreatment with glyburide. In sununary, SKP-30450 and SKP-30818 showed greater negative inotropic and vasorelaxant effect than lemakalim in rat aorta with order of potency of SKP-30450 > SKP-30818 > lemakalim. These actions are suggested to be mediated at least in part by a mechanism which involves the opening of ATP-sensitive potassium channel.

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Separation and Purification of Effective Components from the Alisma orientale and its Application as a Cosmeceutical Ingredient (택사추출물의 성분분리와 화장품 원료로서의 특성)

  • Lee, Dae-Woo;Kim, Young-Jin;Kim, Young-Sil;Kim, Jong-Heon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.32 no.1 s.55
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    • pp.23-28
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    • 2006
  • In this study, we performed anti-oxidation, whitening, cell recovery and anti-inflammation effects with Alisma orientale to evaluate the cosmeceutical properties. Alisma orientate extract (30, 70, 100 % MeOH) exhibited a significant tree radical scavenging effect against 1,1-diphenyl-2-picryl hydrazine (DPPH) radical generation and showed tyrosinase inhibition effect in a dose dependent manner (over 0.5% concentration). In cell proliferation assay using human fibroblast, it didn't show any proliferation effect but showed safety from cytotoxicity under 0.05% concentration. For whitening assay, we evaluated the melanin synthesis rate using B16 melanocyte and it showed a significant inhibitory effect (up to 40% under 0.05% concentration). After major screening assay, we separate 3 fractions from Alisma orientate extract by MPLC and performed cell recovery assay, melanin synthesis inhibition assay and anti-inflammatory assay. The third fraction showed a cell recovery effect over 30% against radical damage and remarkable repression in melanin synthesis and COX-2 synthesis.