• Title/Summary/Keyword: 반응 억제

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Anti-Allergic Effects of Nodakenin in IgE/Ag-Induced Type I Hypersensitivity (노다케닌의 항 알러지 효과)

  • Kim, Yong-Jae;Park, Sae-Jin;Kim, Tack-Joong
    • Journal of Life Science
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    • v.21 no.12
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    • pp.1721-1725
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    • 2011
  • Mast cells are major effector cells associated with allergic responses. They are activated through the release of histamine, arachidonic acid, and proinflammatory cytokines. We investigated the effect of nodakenin, derived from the roots of Angelica gigas Nakai, on mast cell degranulation and on an allergic response in an animal model. We also investigated the effect of nodakenin on expression of multiple cytokines. Nodakenin suppressed the release of ${\beta}$-hexosaminidase, a marker of degranulation, as well as the expression of interleukin IL-4 and TNF-${\alpha}$ mRNA. Nodakenin inhibited the passive cutaneous anaphylaxis (PCA) reaction in ICR mice in a dose-dependent manner. These results suggest that nodakenin can inhibit mast cell degranulation through the inhibition of IL-4 and TNF-${\alpha}$ mRNA expression, and that nodakenin may potentially serve as an anti-allergic agent.

Hepatitis E Virus Inhibits Activation of Signaling Molecules Involved in Induction of Type I Interferon (E형 간염 바이러스에 의한 제 1형 인터페론 신호전달분자 활성 억제)

  • Myoung, Jinjong
    • Microbiology and Biotechnology Letters
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    • v.46 no.4
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    • pp.320-325
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    • 2018
  • Hepatitis E virus (HEV) infection accounts for 20 million annual infections worldwide. HEV can be fatal in approximately 20-30% of pregnant women. HEV infections are normally self-limiting and mostly asymptomatic. However, in patients with insufficient immunity, such as acquired immunodeficiency syndrome patients, chronic and often fatal infections may ensue. Therefore, it is likely that host immune responses, especially interferon responses, play a critical role in HEV infection control. Here, we report that an HEV-encoded non-structural protein down-regulates type I interferon response. In addition, some other immune genes involved in the induction of type I interferon may be regulated as well. Detailed molecular mechanisms are currently being studied.

Effects of Low-Level Visual Attributes on Threat Detection: Testing the Snake Detection Theory (저수준 시각적 특질이 위협 탐지에 미치는 효과: 뱀 탐지 이론의 검증)

  • Kim, Taehoon;Kwon, Dasom;Yi, Do-Joon
    • Science of Emotion and Sensibility
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    • v.23 no.3
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    • pp.47-62
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    • 2020
  • The snake detection theory posits that, due to competition with snakes, the primate visual system has been evolved to detect camouflaged snakes. Specifically, one of its hypotheses states that the subcortical visual pathway mainly consisting of koniocellular cells enables humans to automatically detect the threat of snakes without consuming mental resources. Here we tested the hypothesis by comparing human participants' responses to snakes with those to fearful faces and flowers. Participants viewed either original images or converted ones, which lacked the differences in color, luminance, contrast, and spatial frequency energies between categories. While participants in Experiment 1 produced valence and arousal ratings to each image, those in Experiment 2 detected target images in the breaking continuous flash suppression (bCFS) paradigm. As a result, visual factors influenced the responses to snakes most strongly. After minimizing visual differences, snakes were rated as being less negative and less arousing, and detected more slowly from suppression. In contrast, the images of the other categories were less affected by image conversion. In particular, fearful faces were rated as greater threats and detected more quickly than other categories. In addition, for snakes, changes in arousal ratings and those in bCFS response times were negatively correlated: Those snake images, the arousal ratings of which decreased, produced increased detection latency. These findings suggest that the influence of snakes on human responses to threat is limited relative to fearful faces, and that detection responses in bCFS share common processing mechanisms with conscious ratings. In conclusion, the current study calls into question the assumption that snake detection in humans is a product of unconscious subcortical visual processing.

Involvement of spermine in Control of Ethylene-Mediated Growth Response in Ranunculus sceleratus Petioles (Ranunculus sceleratus 엽병의 에틸렌 매개 생장반응조절에 있어서 Spermine의 관여)

  • 정미숙
    • Journal of Plant Biology
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    • v.35 no.4
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    • pp.425-429
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    • 1992
  • Cell elongation is known to be promoted by ethylene in petioles of Ranunculus sceleratus. Treatment of petiole segments with spermine resulted in an inhibition of cell elongation and of ethylene biosynthesis in the presence of applied auxin. Dose response curve for the spermine inhibition of auxin-induced ethylene production appeared similar to that of ACC-based ethylene production suggesting that the polyamine inhibits ethylene biosynthesis by blocking the conversion of ACC to etylene. Auxin-induced ethylene production was significantly promoted by treatment of the tissue with either DFMA or DFMO. specific inhibitors of polyamine biosynthesis. Increased level of ethylene production by DFMA was found to be completely abolished by application of exogenous spermine at a high concentration. These results indicate that endogenous spermine plays a regulatory role in the growth response of Ranunculus petioles to auxin and ethylene.hylene.

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ACE 억제제를 위한 펩타이드 등입체성 분자 합성 연구

  • 김병현;류은정
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.04a
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    • pp.121-121
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    • 1993
  • Angiotensin Converting Enzyme (ACE)의 효과적인 억제제를 합성하기 위하여 ketomethylene dipeptide isoster와 2-isoxazoline dipeptide isoster를 얻는 방법을 확립하였다. 상기 등입체성 분자들은 아미노산으로부터 유도된 아미노 니트릴 옥사이드의 고리더함반응을 이용하여 효율적으로 합성하였다. 얻어진 이 화합물로부터 ACE 억제제 후보물질 (1, 2)의 합성이 연구되고 있다.

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A Study on the Mechanism of Calcium Binding Inhibition of Cardiac Sarcoplasmic Reticulum by Oxygen Free Radicals (산소대사물에 의한 심장근 Sarcoplasmic reticulum의 칼슘운반 억제 기전에 관한연구)

  • Kim, Hae-Won;Chung, Myung-Hee;Kim, Myung-Suk;Park, Chan-Woong
    • The Korean Journal of Pharmacology
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    • v.21 no.2
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    • pp.79-89
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    • 1985
  • Mechanism of calcium transport inhibition of cardiac sarcoplasmic reticulum (SR) by oxygen free radicals was examined. Effects of oxygen free radicals generated by xanthine/xanthine oxidase (X/XO) system on isolated porcine ventricle SR were studied with respect to its calcium binding, lipid peroxidation, SH-group content and alteration of membrane protein components. The results are as follows. 1) Calcium binding of isolated SR was markedly inhibited by X/XO. 2) During the incubation of sarcoplasmic reticulum with xanthine/xanthine oxidase, there were marked inclose in lipid peroxidation and reduction of SH-group content. 3) An antioxidant, p-phenylenediamine effectively prevented the lipid peroxidation but partially prevented the calcium binding inhibition of X/XO treated SR. 4) The reduction of SH-group content of SR treated with X/XO was partially prevented by p-phenylendiamine. 5) When modifying SH-group of SR by treatment with DTNB, the inhibition of calcium binding activity was partially prevented. 6) On gel-permeation chromatography of X/XO-treated sarcoplasmic reticulum, there was an increase of small molecular weight products, probably protein degradation products. 7) Semicarbazide, which prevents the cross-linking reaction of protein components, did not affect the calcium binding inhibition of X/XO-treated SR. From these results, it is suggested that the inhibition of calcium binding of SR by oxygen free radicals results from the consequence of multiple changes of SR components, which are lipid peroxidation, SH-group oxidation and degradation of protein components.

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Inhibitory Effects of Several Korean Traditional Herbs on Anaphylactic Reaction and Mast Cell Activation (아나필락시스 반응과 비만세포 활성화에 대한 한국전통약제의 억제효과)

  • Chai, Ok-Hee
    • Applied Microscopy
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    • v.40 no.4
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    • pp.201-209
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    • 2010
  • Korean traditional herbs, especially Anemarrhena asphodeloides (A. asphodeloides), Salvia miltiorrhiza (S. miltiorrhiza), and Terminalia chebula (T. chebula) have been known to have the immunomodulatory, anti-tumor, and anti-inflammatory effects. However, direct cellular mechanism underlying the mast cell-mediated anaphylaxis-like reaction has poorly been understood. In the present study, the effects of the methanol extracts of A. asphodeloides (MEAA), S. miltiorrhiza (MESM), and T. chebula (METC) on anaphylactic reaction were investigated. Using in vitro and in vivo experiments, the influences of MEAA, MESM, and METC on the compound 48/80-induced anaphylaxis-like reaction and mast cell activation, and IgEmediated PCA were examined. Results are below; 1) MEAA, MESM, and METC significantly inhibited systemic anaphylaxis-like reaction, ear swelling response, and IgE-mediated PCA. 2) the compound 48/80-induced mast cell degranulation, histamine release of rat peritoneal mast cells (RPMC) were significantly inhibited by the pretreatment with MEAA, MESM, and METC, and 3) the compound 48/80-induced calcium influx in RPMC was significantly inhibited by the pretreatment with MEAA, MESM, and METC. These results suggest that MEAA, MESM, and METC may be an activity to inhibit the compound 48/80-induced or anti-DNP IgE-mediated anaphylactic reactions by blocking histamine release and calcium uptake into RPMC. MEAA, MESM, and METC potentially may serve as an effective therapeutic tool for allergic diseases.

The Effect of Polyphenol Oxidase on Deodorizing Activity of Apple Extract against Methyl Mercaptan (사과 추출물의 구취억제효과에 대한 Polyphenol Oxidase의 영향)

  • 조상원;곽기석;이주항;윤영수;구연숙
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.6
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    • pp.1301-1304
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    • 2001
  • Deodorizing activity of polyphenol cxidase (PPO) extracted from apples was investigated by measuring the changes of methyl mercaptan as an indicator of halitosis in human mouths. In the studies of apple extracts on deodorizing activity, the deodorizing activity was increased with the amount of apple extracts. In the cases of adding PPO to the low molecular fraction of apple extracts, the deodorizing activities were increased with the amount of the law molecular fraction of apple extracts and the reaction time of the extracts with PPO. Deodorizing activities of PPO is thought that o-quinone as an intermidiate produced by an oxidative reaction of PPO during enzymatic browning reactions may react with methyl mercaptan to form a non-volatile and sulfur-containing compound .

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Desmutagenic Action of Sugar Degradation Products (당(糖) 분해생성물의 돌연변이원성 억제작용)

  • Kim, Seon-Bong;Kim, In-Soo;Yeum, Dong-Min;Park, Yeung-Ho
    • Korean Journal of Food Science and Technology
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    • v.20 no.1
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    • pp.119-124
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    • 1988
  • The desmutagenic effects of ${\alpha}$-hydroxycarbonyl compounds, such as glyceraldehyde, glycolaldehyde, dihydroxyacetone, furfural, 5-hydroxymethylfurfural, maltol, acetol and acetoin and ${\alpha}$-dicarbonyls, such as diacetyl, glyoxal, methyl glyoxal and 2, 3-pentanedione were investigated against the mutagenic heterocyclic amines, such as Trp-P-1, Trp-P-2, Glu-P-1, Glu-P-2 and IQ. Most of the carbonyl compounds suppressed the mutagenicity of heterocyclic amines for S. typhimurium TA98, ${\alpha}$-dicarbonyl compounds showing a higher desmutagenic effect than ${\alpha}$-hydroxycarbonyl compounds. Among the ${\alpha}$-hydroxycarbonyl compounds, glyceraldehyde, glycolaldehyde and dihy-droxyacetone showed more effective desmutagenicity, and diacetyl among the ${\alpha}$-dicabonyl compounds had the highest desmutagenic effect. These carbonyl compounds alone also showed mutagenicity to S. typhimurium TA100 without S-9 mix. The reaction of carbonyl compounds with mutagenic heterocyclic amines also eliminated the mutagenicity of the former for S. typhimurium TA100.

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The Effect of Interleukin-10 on KC Gene Expression in Mouse Peritoneal Macrophages (케모카인 KC 유전자 발현에 대한 Interleukin-10의 억제작용)

  • Kim, Hee-Sun
    • Journal of Yeungnam Medical Science
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    • v.15 no.1
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    • pp.47-54
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    • 1998
  • Interleukin-10(IL-10) inhibits production of a wide range of cytokines in various cell types and transcriptionally inhibits lipopolysaccharide (LPS)-induced expression of proinflammatory mediators. Cytokine expression by macrophages is an important aspect to ochestrate inflammatory responses. As an approach to identify mechanistic targets of IL-10, it was examined the time course for expression of KC(murine homologue of Gro) gene in murine peritoneal macrophages stimulated with LPS with or without IL-10. The effect of IL-10 on LPS induced KC mRNA expression was delayed and only seen after 1 hour treatment. Pretreatment with IL-10 did not eliminate the delayed inhibitory response nor increase the magnitude of suppression. These effects did not depend upon time of IL-10 treatment but the time of LPS treatment. LPS-induced KC mRNA expression by inhibitory action of IL-10 was not controlled at the level of transcription. The result indicates that IL-10 acts late in the process of KC gene expression and that the prominant site of action may be mRNA stability or translation.

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