• Title/Summary/Keyword: Inhibiting Effect

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Self-Corrosion Protection of Polymer Cementitious Materials Using Terpolymer Powders with a Nitrite-type Hydrocalumite (아질산형 hydrocalumite와 터폴리머 분말수지를 병용한 폴리머 시멘트계 재료의 자기방청기능)

  • Hong, Sun-Hee;Kim, Wan-Ki
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2010.05a
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    • pp.73-76
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    • 2010
  • This study deals with the properties of polymer-modified mortars with a nitrite-type hydrocalumite, which are effectively used as intelligent patch materials for deteriorated reinforced concrete structures. The calumite is a material that can adsorb the chloride ions (Cl-) causing the corrosion of reinforcing bars and liberate the nitrite ions (NO2-) inhibiting the corrosion in reinforced concrete, and can provide a self-corrosion inhibition function to the reinforced concrete. Polymer-modified mortars using hydrocalumite and terpolymer powders are prepared with various calumite contents and polymer-binder ratios, and tested for corrosion inhibition. Subsequently, regardless of the polymer-binder ratio, the replacement of ordinary portland cement with the calumite has a marked effect on the corrosion-inhibiting property of the polymer-modified mortars.

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Antitumor Activity of Crude Sesaminol in Sesame Seed

  • Ryu, Su-Noh;Lee, Bong-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.3
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    • pp.168-171
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    • 1998
  • Sesaminol in sesame seed was postulated to have antitumor activity. The present study was performed to characterize the role of crude sesaminol extracted from sesame seed (Sesame Crude Sesaminol; SCS) on inhibiting the in vitro growth of human leukemia HL-60 cells. SCS inhibited the growth of human leukemia HL 60 cells in culture and macromolecular synthesis in a dose and time dependent manner. The cytostatic range of SCS concentration was found to be 60 to 100 $\mu\textrm{g}$/ml. SCS concentration greater than 200 $\mu\textrm{g}$/mlwere cytocidal to HL-60 cells. When SCS concentraction was 6 $\mu\textrm{g}$/mland 50 $\mu\textrm{g}$/ml the synthesis of HL-60 cells was inhibited by 35% for DNA, 6% for RNA and 5% for protein and 83% for DNA, 76% for RNA and 60% for protein. Of specific interest was the irreversible effect of SCS in inhibiting DNA synthesis of HL-60 cells. This was evidenced from the fact that, even after washed with PBS three times, preincubated HL-60 cells still showed the inhibited DNA synthesis.

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Protective Effects of Phosphate and ATP Pretreatment on Pb-Inhibiting Photosystem II Activity (연(Pb)에 의한 광계 II 활성억제에 미치는 인산 및 ATP 전처리의 보호효과)

  • 성민웅
    • Journal of Plant Biology
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    • v.25 no.1
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    • pp.21-36
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    • 1982
  • The activity of photosystem II in isolated chloroplast form the leaves of Sedum sarmentosum was measured. The photoreduction rate of DCPIP by photosystem II showed the circadian rhythm with a peak at near midday sample for a continuing fine day and at near afternoon between nidday and sunset sample for a continuing cloudy day in summer. The optimum light intensity of photoreduction by photosystem II in the chloroplast preparation was about 5~9$\times$$10^4$ lux. The saturated light intensity was over 9$\times$$10^1$lux. Photosystem II activity was inhibited by even the lowest concentration of lead. When Pi and ATP of the same concentration as Pb were added to the reaction mixture containing Tris buffer lacking of Pi prior to Pb incubation, photosystem II activity was protected from Pb-inhibiting effect by the pretreament of Pi and ATP. It was assumed that Pb inhibiiton was probably due to one, P-depriving by the precipitates of $Pb_3$ $($Pb_4$)_2$ in the reaction mixture and the other, partially Pb-combing with Pi groups of the active site of photosystem II.

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Tetrandrine Exerts a Radiosensitization Effect on Human Glioma through Inhibiting Proliferation by Attenuating ERK Phosphorylation

  • Ma, Ji-wei;Zhang, Yong;Ye, Ji-cheng;Li, Ru;Wen, Yu-Lin;Huang, Jian-xian;Zhong, Xue-yun
    • Biomolecules & Therapeutics
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    • v.25 no.2
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    • pp.186-193
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    • 2017
  • Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to have a radiosensitization effect on tumors. However, its effects on human glioma and the specific molecular mechanisms of these effects remain unknown. In this study, we demonstrated that Tet has a radiosensitization effect on human glioma cells. It has been hypothesized that Tet has a radiosensitization effect on glioma cells by affecting the glioma cell cycle and DNA repair mechanism and that ERK mediates these activities. Therefore, we conducted detailed analyses of the effects of Tet on the cell cycle by performing flow cytometric analysis and on DNA repair by detecting the expression of phosphorylated H2AX by immunofluorescence. We used western blot analysis to investigate the role of ERK in the effect of Tet on the cell cycle and DNA repair. The results revealed that Tet exerts its radiosensitization effect on glioma cells by inhibiting proliferation and decreasing the expression of phosphorylated ERK and its downstream proteins. In summary, our data indicate that ERK is involved in Tet-induced radiosensitization of glioma cells via inhibition of glioma cell proliferation or of the cell cycle at G0/G1 phase.

Effects of Pyeonggangaeuljihyeol-tang(PGJT) Extract on Anti-inflammatory, Antioxidant and Anti-aging (평간개울지혈탕(平肝開鬱止血湯)의 항염증, 항산화 및 항노화에 미치는 영향)

  • Kyoung Won Lee;Young Chae Song;Hee Taek Kim
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.37 no.1
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    • pp.29-41
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    • 2024
  • Objectives : The purpose of this study is to confirm the anti-inflammatory, antioxidant and anti-aging efficacy of Pyeonggangaeuljihyeol-tang(PGJT) extract. Methods : In order to confirm the anti-inflammatory activity of PGJT extract, the inhibitory effect on NO PGE2 production were evaluated and the expression level of iNOS, COX-2 and IL-6 mRNA were measured through qRT-PCR, Antioxidant activity was evaluated for radical scavenging activity using DPPH and ABTS, anti-aging activity was evaulated for collagenase, elastase, tyrosinase and L-DOPA oxidation inhibitory activity. Results : PGJT extract shows anti-inflammatory effect by inhibiting the production of NO and PGE2 by reducing the expression level of iNOS, COX-2 and IL-6 mRNA, antioxidant effect by increasing DPPH and ABTS scavenging abillity in a concentration dependent manner. In addition, the anti-aging effect was confirmed by inhibiting collagenase, elastase, tyrosinase production and L-DOPA oxidation. Conclusion : This suggests that PGJT showed an overall excellent anti-inflammatory effect and an inhibitory effect on the activity of antioxidant and anti-aging related enzymes.

Effect of Probiotic Clostridium butyricum NCTC 7423 Supernatant on Biofilm Formation and Gene Expression of Bacteroides fragilis

  • Shi, Da-Seul;Rhee, Ki-Jong;Eom, Yong-Bin
    • Journal of Microbiology and Biotechnology
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    • v.30 no.3
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    • pp.368-377
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    • 2020
  • Enterotoxigenic Bacteroides fragilis (ETBF) is the main pathogen causing severe inflammatory diseases and colorectal cancer. Its biofilm plays a key role in the development of colorectal cancer. The objective of this study was to determine the antagonistic effects of cell-free supernatants (CFS) derived from Clostridium butyricum against the growth and biofilm of ETBF. Our data showed that C. butyricum CFS inhibited the growth of B. fragilis in planktonic culture. In addition, C. butyricum CFS exhibited an antibiofilm effect by inhibiting biofilm development, disassembling preformed biofilms and reducing the metabolic activity of cells in biofilms. Using confocal laser scanning microscopy, we found that C. butyricum CFS significantly suppressed the proteins and extracellular nucleic acids among the basic biofilm components. Furthermore, C. butyricum CFS significantly downregulated the expression of virulence- and efflux pump-related genes including ompA and bmeB3 in B. fragilis. Our findings suggest that C. butyricum can be used as biotherapeutic agent by inhibiting the growth and biofilm of ETBF.

Free Radical Scavenging Activity and Inhibition of Linoleic Acid Peroxidation of Commercial Tocotrienol Fraction

  • Kim, Joo-Shin;Chung, Hau-Yin
    • Preventive Nutrition and Food Science
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    • v.12 no.3
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    • pp.177-180
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    • 2007
  • Tocotrienols (T3) are minor plant constituents found abundantly in rice bran, which provide a significant source of vitamin E in animal feeds. T3 was reported to have an intrinsic hypocholesterolemic effect by inhibiting HMG-Co A reductase. It has similar antioxidative properties as tocopherols in food and biological system due to their similar chemical structures. However, the antioxidant activity and mechanism of T3 to scavenge free radicals and to inhibit the peroxidation of linoleic acid are less understood. The purpose of this study was to investigate the scavenging effect of T3 on free radicals and its inhibition of peroxide formation. Free radical scavenging activity was monitored by the DPPH (1,1-diphenyl-2-picrylhydrazyl) method whereas inhibition of linoleic acid peroxidation was evaluated using the thiocyanate method. Thiobarbituric acid (TBA) test was used to determine malonaldehyde formation from linoleic acid peroxidation. Free radical scavenging activity increased with increasing concentration levels of T3. T3 exhibited 38.2, 78.6, 92.7 and 96.2% radical scavenging activity at concentrations of 2, 8, 32 and 128 ppm, respectively. At 128 ppm, it was highly effective in inhibiting linoleic acid peroxidation. The activity of T3 evaluated by the thiocyanate method showed low absorbance values indicating a high level of antioxidant activity. All treatments showed similar trends in antioxidant activity when evaluated by both the thiocyanate method and TBA test.

Effects of Crude ε-poly-L-lysine in Streptomyces albulus Broth on Suppression of Microbial Growth in Korean Kimchi (폴리리신을 함유한 Streptomyces albulus 배양액의 김치미생물 성장억제 효과)

  • Kim, Kwang-sub;Lee, Garpee;Sun, Heung-suk;Ahn, Chi-min;Park, Chanyoung
    • Journal of the Korean Society of Industry Convergence
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    • v.2 no.1
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    • pp.91-95
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    • 1999
  • The Streptomyces albulus broth, when the polylysine in the broth, that has powerful growth inhibiting effect far many microbes, is its maximum, had filtered off the cells, to use the broth as preservative for keeping favorable taste of Korean Kimchi. Some microorganisms in their specific growth medium, known to deteriorate the useful nutrient of the Kimchi, has grown with different amounts of the inhibiting broth, to determine the minimum growth inhibition concentration. The ${\varepsilon}$-poly-L-lysine had been identified from the IR spectroscopic analysis of the purified poly lysine of the broth from ion exchange chromatographic separation. The content of the polylysine had been determined by methyl orange decoloration effect. Though the minimum inhibition concentration, evaluated by the naked eye based on the conventional method measuring the turbid feature after 18 hours of culture, has different values each other, the observed effects confirmed that the crude broth could be used as a natural preservative for the Kimchi in extending the fair taste.

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Quercitrin Gallate Down-regulates Interleukin-6 Expression by Inhibiting Nuclear Factor-kB Activation in Lipopolysaccharide-stimulated Macrophages

  • Min, Kyung-Rak;Kim, Byung-Hak;Chang, Yoon-Sook;Kim, Young-Soo
    • Natural Product Sciences
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    • v.12 no.2
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    • pp.113-117
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    • 2006
  • Quercitrin gallate was previously isolated from Persicaria lapathifolia (Polygonaceae) as an inhibitor of superoxide production. In the present study, quercitrin gallate was found to inhibit interleukin (IL)-6 production in lipopolysaccharide (LPS)-stimulated macrophages RAW 264.7 with an $IC_{50}$ value of $63\;{\mu}M$. Furthermore, quercitrin gallate attenuated LPS-induced synthesis of IL-6 transcript but also inhibited LPS-induced IL-6 promoter activity, indicating that the compound could down-regulate IL-6 expression at the transcription level. Since nuclear factor (NF)-kB has been shown to play a key role in LPS-inducible IL-6 expression, an effect of quercitrin gallate on LPS-induced NF-kB activation was further analyzed. Quercitrin gallate exhibited a dosedependent inhibitory effect on LPS-induced nuclear translocation of NF-kB without affecting inhibitory kB (IkB) degradation, and subsequently inhibited LPS-induced NF-kB transcriptional activity in macrophages RAW 264.7. Taken together, quercitrin gallate down-regulated LPS-induced IL-6 expression by inhibiting NF-kB activation, which could provide a pharmacological potential of the compound in IL-6-related immune and inflammatory diseases.

Inhibitory Effects on Platelet Aggregation and Blood Coagulation by Concurrent Administration of Trifusal and Ibudilast (Triflusal과 Ibudilast 동시처리에 의한 혈소판응집 및 혈액응고 억제효과)

  • Hwang, In-Young;Sohn, Yoon-Ah;Hwang, Seon-A;Koo, Yean-Kyoung;Kim, Sun-Young;YunChoi, Hye-Sook;Kwon, Soon-Kyoung;Jeong, Choon-Sik
    • YAKHAK HOEJI
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    • v.56 no.4
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    • pp.248-253
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    • 2012
  • This study aims to develop a novel regimen for enhanced efficacy and reduced side effect in inhibiting platelet aggregation and blood coagulation by concurrent administration of triflusal and ibudilast as anticoaggulants. The result shows this combination of triflusal and ibudilast (300~500 ${\mu}M$, respectively) has additive effect in inhibiting platelet aggregation and blood coagulation over the administration of truflusal or ibdilast as a single treatment. This pharmaceutical composition is expected to be useful for the prevention or treatment of various diseases and symptoms, for example, ischemic heart disease, ischemic cerebral infarction, arteriosclerosis, and thrombosis caused by the insertion of a stent.