• 제목/요약/키워드: Blocking signal

검색결과 189건 처리시간 0.03초

Uncaria sinensis(OIi.) Havil Suppressendotoxin-induced Proinflammatory Responses through Blocking ERK Signaling Pathways

  • Park, Tai-Guang;Moon, Hyung-Cheal;Cho, Hae-Joong;Seo, Sang-Wan;Jung, Won-Sek;Song, Ho-Joon;Park, Sung-Joo
    • 동의생리병리학회지
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    • 제21권5호
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    • pp.1297-1302
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    • 2007
  • Uncaria sinensis(OIi.) Havil (USH) is used in traditional Korean medicine to treat inflammation such as amebic dysentery. In this study, we investigated the anti-inflammatory effect of USH. The water extract of USH significantly inhibits lipopolysaccharide (LPS)-induced nitrite oxide (NO), tumor necrosis factor $(TNF)-{\alpha}$, interleukin (IL)-6and IL-12 productions in murine peritoneal macrophages. Furthermore, USH selectively inhibited activation of the extracellular signal-regulated kinase (ERK) but not of p38 MAPK, c-Jun N-terminal kinase (JNK) and nuclear $factor-{\kappa}B$ $(NF-{\kappa}B)$. In murine model, we found that administration of USH reduced serum levels of $TNF-{\alpha}$, IL-6 and IL-12 productions in LPS-treated mice. Our results suggest that USH exerts ant-inflammatory effects in macrophages via inhibition of ERK activation and may be a useful therapeutic approach to inflammatory diseases.

Interleukin-13 Increases Podocyte Apoptosis in Cultured Human Podocytes

  • Lee, Keum Hwa;Oh, Ji Young;Seong, Su-Bin;Ha, Tae-Sun;Shin, Jae Il
    • Childhood Kidney Diseases
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    • 제22권1호
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    • pp.22-27
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    • 2018
  • Purpose: Podocytes are important architectures that maintain the crucial roles of glomerular filtration barrier functions. Despite this structural importance, however, the mechanisms of the changes in podocytes that can be an important pathogenesis of minimal change nephrotic syndrome (MCNS) are not clear yet. The aim of this study was to investigate whether apoptosis is induced by interleukin (IL)-13 in cultured human podocytes. Methods: Human podocytes were treated with different IL-13 doses and apoptotic cells were analyzed using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL assay) and fluorescence-activated cell sorting (FACS). Results: The IL-13 increased the number of TUNEL-positive cells in a dose-dependent manner at 6 and 18 hours (P<0.05 and P<0.05, respectively). The apoptosis rate was appeared to be increased slightly in the IL-13-stimulated podocytes (8.63%, 13.02%, and 14.46%; 3, 10 and 30 ng/mL, respectively) than in the control cells (7.66%) at 12 hours by FACS assay. Conclusion: Our study revealed that IL-13 expression may increase podocyte apoptosis. Blocking the IL-13 signal pathway can potentially play an important role in regulating the apoptosis of podocytes.

Electrochemical Immunosensor Using a Gas Diffusion Layer as an Immobilization Matrix

  • Kim, Yong-Tae;Oh, Kyu-Ha;Kim, Joo-Ho;Kang, Hee-Gyoo;Choi, Jin-Sub
    • Bulletin of the Korean Chemical Society
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    • 제32권6호
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    • pp.1975-1979
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    • 2011
  • The modification of a gas diffusion layer (GDL), a vital component in polymer electrolyte fuel cells, is described here for use in the electrochemical detection of antibody-antigen biosensors. Compared to other substrates (gold foil and graphite), mouse anti-rHBsAg monoclonal antibody immobilized on gold-coated GDL (G-GDL) detected analytes of goat anti-mouse IgG antibody-ALP using a relatively low potential (-0.0021 V vs. Ag/AgCl 3 M NaCl), indicating that undesired by-reactions during electrochemical sensing should be avoided with G-GDL. The dependency of the signal against the concentration of analytes was observed, demonstrating the possibility of quantitative electrochemical biosensors based on G-GDL substrates. When a sandwich method was employed, target antigens of rHBsAg with a concentration as low as 500 ng/mL were clearly measured. The detection limit of rHBsAg was significantly improved to 10 ng/mL when higher concentrations of the 4-aminophenylphosphate monosodium salt (APP) acting on substrates were used for generating a redox-active product. Additionally, it was shown that a BSA blocking layer was essential in improving the detection limit in the G-GDL biosensor.

Sclerotiorin and Isochromophilone IV: Inhibitors of Grb2-Shc Interaction, Isolated from Penicillium multicolor F1753

  • Nam, Ji-Youn;Son, Kwang-Hee;Kim, Hyae-Kyeong;Han, Mi-Young;Kim, Sung-Uk;Choi, Jung-Do;Kwon, Byoung-Mog
    • Journal of Microbiology and Biotechnology
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    • 제10권4호
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    • pp.544-546
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    • 2000
  • Grb2 is an important adaptor protein in the mitogenic Ras signaling pathway of receptor tyrosine kinases, and contains one SH2 domain and two SH3 domains. The SH2 domain binds to specific phosphotyrosine motifs on receptors or adaptor proteins such as Shc. The SH2 domain antagonists may lead to blocking of the oncogenic Ras signals and to developing new antitumor agents. In the course of screening SH2 antagonists from natural sources, cslerotiorin (1) and isochromophilone IV (2) were isolated from a strain, Penicillium multicolor F1753, and their structures were established by NMR spectral data. The metabolites significantly inhibited the binding between the Grb2-SH2 domain and phosphopeptide derived from the Shc protein, with $IC_{50}$ values of $22{\;}\mu\textrm{M}{\;}and{\;}48{\;}\mu\textrm{M}$ for (1) and (2), respectively. The compounds are the first nonpeptidic inhibitors of the SH2 domain from a natural source.

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The pepsinolytic hydrolysate from Johnius belengerii frame inhibited LPS-stimulated production of pro-inflammatory mediators via the inactivating of JNK and NF-κB pathways in RAW 264.7 macrophages

  • Heo, Seong-Yeong;Ko, Seok-Chun;Jung, Won-Kyo
    • Fisheries and Aquatic Sciences
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    • 제21권5호
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    • pp.14.1-14.8
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    • 2018
  • The objective of this study was to investigate the anti-inflammatory effects of the pepsinolytic hydrolysate from the fish frame, Johnius belengerii, on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The J. belengerii frame hydrolysate (JFH) significantly suppressed nitric oxide (NO) secretion on LPS-stimulated RAW264.7 macrophages. Moreover, the JFH markedly inhibited the levels of protein and mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, the LPS-stimulated mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\beta}$, and IL-6 was downregulated when cells were cultured with the JFH. The JFH significantly reduced the phosphorylation of c-Jun N-terminal kinase (JNK) and the translocation of nuclear factor-kappa B ($NF-{\kappa}B$) in macrophages. As the result, the JFH has the potential anti-inflammatory activity via blocking the JNK and $NF-{\kappa}B$ signal pathways.

Oridonin Suppresses Proliferation of Human Ovarian Cancer Cells via Blockage of mTOR Signaling

  • Xia, Rong;Chen, Sun-Xiao;Qin, Qin;Chen, Yan;Zhang, Wei-Wei;Zhu, Rong-Rong;Deng, An-Mei
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권2호
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    • pp.667-671
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    • 2016
  • Oridonin, an ent-kaurane diterpenoid compound isolated from the traditional Chinese herb Rabdosia rubescens, has shown various pharmacological and physiological effects such as anti-tumor, anti-bacterial, and anti-inflammatory properties. However, the effect of oridonin on human ovarian cancer cell lines has not been determined. In this study, we demonstrated that oridonin inhibited ovarian cancer cell proliferation, migration and invasion in a dose-dependent manner. Furthermore, we showed oridonin inhibited tumor growth of ovarian cancer cells (SKOV3) in vivo. We then assessed mechanisms and found that oridonin specifically abrogated the phosphorylation/activation of mTOR signaling. In summary, our results indicate that oridonin is a potential inhibitor of ovarian cancer by blocking the mTOR signaling pathway.

Agent 기반 변압기의 Sympathetic inrush 판단 방법 (Agent based algorithm for detecting sympathetic inrush of a transformer)

  • 강용철;이병은;박종민;황태근;장성일;김용균
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.234-235
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    • 2006
  • The protection relay keeps electric power facilities by using signals of the voltage and current which are input and output terminals of each equipment. Each relay performances protection algorithm by using informations of own protecting zone. To prevent the mal-operation in inrush current, established transformer differential protection method uses the second harmonics as blocking signal. This method is not operate at the initial inrush. However, in case of the parallel operation, if the initial inrush is occurred in one transformer which is generated, the sympathetic inrush Is occurred in adjacent transformer. This paper approach the sympathetic inrush detecting algorithm of a transformer based on agent. Proposed algorithm, when inrush current occurred, distinguish sympathetic inrush or not by using differential current of adjacent transformer. This algorithm have the advantage of the distinguishing initial inrush and sympathetic inrush at operation of parallel transformer

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영상 전류를 이용한 변류기 개방 판단 알고리즘 (Algorithm for detecting the failure of a current transformer using the zero-sequence current)

  • 강용철;이병은;이현웅;김유다;박준수;이미선;박지연;이보은
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.163-164
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    • 2006
  • A current differential relay has been used for transmission line protection. The relay may maloperate in the case of a failure of the secondary circuit of a current transformer (CT) because the differential current is produced. This paper presents an algorithm to detect a failure of a CT using the zero-sequence current. If the magnitude of the zero-sequence current is the same as the magnitude of the current of the other healthy phases, a failure of a CT is detected and then the blocking signal is activated. The proposed algorithm prohibit the maloperation of a differential relay in the case of a CT failure and thus increase the security of the relay.

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Silymarin Inhibits Cytokine-Stimulated Pancreatic Beta Cells by Blocking the ERK1/2 Pathway

  • Kim, Eun Jeong;Kim, Jeeho;Lee, Min Young;Sudhanva, Muddenahalli Srinivasa;Devakumar, Sundaravinayagam;Jeon, Young Jin
    • Biomolecules & Therapeutics
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    • 제22권4호
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    • pp.282-287
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    • 2014
  • We show that silymarin, a polyphenolic flavonoid isolated from milk thistle (Silybum marianum), inhibits cytokine mixture (CM: TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$)-induced production of nitric oxide (NO) in the pancreatic beta cell line MIN6N8a. Immunostaining and Western blot analysis showed that silymarin inhibits iNOS gene expression. RT-PCR showed that silymarin inhibits iNOS gene expression in a dose-dependent manner. We also showed that silymarin inhibits extracellular signal-regulated protein kinase-1 and 2 (ERK1/2) phosphorylation. A MEK1 inhibitor abrogated CM-induced nitrite production, similar to silymarin. Treatment of MIN6N8a cells with silymarin also inhibited CM-stimulated activation of NF-${\kappa}B$, which is important for iNOS transcription. Collectively, we demonstrate that silymarin inhibits NO production in pancreatic beta cells, and silymarin may represent a useful anti-diabetic agent.

전력선 통신의 실선시험 및 신호특성 분석 (Ship Tests of PLC and Analysis of Its Signal Characteristics)

  • 조성락;백부근;이지은;이동곤;배병덕
    • 대한조선학회논문집
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    • 제47권1호
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    • pp.93-98
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    • 2010
  • In this paper, PLC which can be installed easily and is stable to transfer datum, is tested for approving its application in a real ship. Internet access service, CCTV monitoring, light control and huge sensor communications are needed for enhancing the convenience and safety of passengers and crew in ships. In order to apply PLC in ships, we surveyed some noises interrupting PLC in ships and investigated the PLC characteristics. The Hannara, a training ship of Korea Maritime University, was used for the test. We measured and analyzed blocking noises using by NI's SCXI-1001. When noises of specific frequency band occurred near the PLC frequency band, PLC transfer capacity was low for mass datum. We developed and verified some methods to apply PLC in a ship under lots of noises.