• 제목/요약/키워드: down-regulation

검색결과 1,254건 처리시간 0.029초

Genistein이 햄스터 난소세포의 항산화효소활성과 발현에 미치는 영향 (Effect of Genistein on Activity and Expression of Antioxidant Enzyme in Hamster ovary cells)

  • 김민혜;김안근
    • 약학회지
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    • 제51권1호
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    • pp.75-82
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    • 2007
  • Reactive oxygen species (ROS) are produced in the metabolic process of oxygen in cells. The superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in cells systemize the antioxidant enzymes to control the oxidative stress. Genistein is one of the isoflavonoids, and its role in controlling cellular oxidative stress is presently the active issue at question. In this study; we analyzed genistein-induced survival rates of the CHO-K1 cells, activities of antioxidant enzymes, ROS levels, and expression levels of antioxidant enzyme genes in order to investigate the effect of genistein on cellular ROS production and antioxidative systems in CHO-K1 cells. As results, the survival rate of cells was decreased as the dose of genistein increases (12.5${\sim}$200 ${\mu}$M). Genistein increased cellular ROS levels, while it reduced total SOD activities and the expression of CuZnSOD. In conclusion, we suggest that genistein may induce oxidative stress via down-regulation of SOD.

PC12 세포주에서 Translationally Controlled Tumor Protein에 의한 Mitogen-activated Protein Kinases 활성 조절 (Regulation of Mitogen-activated Protein Kinases by Translatoinally Controlled Tumor Protein in PC12 Cells)

  • 김미연;김미영
    • 약학회지
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    • 제54권5호
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    • pp.323-327
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    • 2010
  • Translationally controlled tumor protein (TCTP) activates basophils to release histamine and causes chronic inflammation. It was also reported that TCTP significantly reduced in brain of Alzheimer's Disease and Down Syndrome as compared to normal person, suggesting that TCTP might be involved in cognitive function. We wondered whether TCTP could act as a general inducer in neurotransmitters release in brain. We, therefore, investigated the role of TCTP in PC12 cell line which expressed neuronal properties. We found that TCTP could activate JNK, and the activity was inhibited by pretreatment of dicoumarol, a JNK inhibitor. However, TCTP could not activate ERK that has known to be involved in neurotransmitter release. These suggest TCTP did not participate in neurotransmitter release from PC12 cells, and TCTP might not be a general inducer in neurotransmitter release.

사향(麝香)의 수용성분(水容性分)이 생쥐 복강내(腹腔內) 거식세포(巨食細胞)의 활성(活性)에 미치는 영향(影響) (Effects of the water soluble fraction of the musk on the activities of murine peritoneal macrophages)

  • 임석린
    • 대한예방한의학회지
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    • 제6권2호
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    • pp.147-155
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    • 2002
  • The musk has been reported to have significant anti-inflammatory activities in clinical use and several animal models and we examined the effects of water soluble fraction(WSF) of the musk on murine peritoneal macrophages. WSF decreased the production of nitric oxide from the lipopolysaccharide(LPS)-treated murine peritoneal macrophages and also reduced the phagocytic activity of macrophages on the opsonized sheep red blood cells(SRBC). Transcriptional expression level of the inducible nitric oxide synthase(iNOS) was also decreased and the viability of the treated macrophages was not affected by WSF, suggesting that the effects could be partly explained by transcriptional regulation. Contrary to down-regulating iNOS expression, WSF slightly increased the release of tumor necrosis factor-alpha$(TNF-{\alpha})$, which implied its selective action on cellular pathways activated by LPS. Our results showed that anti-inflammatory activities of the musk could be partly explained by the inhibitory effects of the water soluble fraction on the macrophageal activation.

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가솔린 차량의 각 요소별 연료소모량 분석을 위한 실험적 연구 (An Experimental Study on Breakdown of Fuel Consumption on a Component Basis in a Gasoline Engine Vehicle)

  • 유정철;송해박;이종화;유재석;박영무;박경석
    • 한국자동차공학회논문집
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    • 제12권1호
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    • pp.153-161
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    • 2004
  • A vehicle fuel economy is one of the most important issues in view of environmental regulation and customer's needs. In order to improve the vehicle fuel economy, great efforts has been carried out on the components bases. However, systematic analysis of vehicle fuel consumption is necessary for the further improvement of vehicle fuel economy. In this paper, a methodology for the breakdown of vehicle fuel consumption was studied and proposed for systematic analysis of the vehicle fuel economy. The energy equation for the vehicle power train was set up for the analysis of the vehicle fuel economy and simplified to be calculated or estimated using the measured data in a vehicle. The amount of fuel that was used in vehicle components under arbitrary driving conditions was quantified.

Numerical Analysis for Development of Vertical Falling Prevention System

  • Kwon, Oh-Heon;Kim, Sang-Tae;Kang, Ji-Woong
    • International Journal of Safety
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    • 제8권2호
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    • pp.1-4
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    • 2009
  • Various falling prevention systems with vertical guided rail have been supplied in order to prevent falling accidents and acquire the long life and cost down for the maintenance. Almost the imported system is composed of a guided rail and the comfort components. It has the mechanism that cannot be dismounted from the guided rail at the accident site. Thus, the aim of this study is to develop a falling prevent system that has a direct dismounting function, which can release easily from the falling accident point. This system has a high durability and robust. And the cost efficiency of the system and safety for workers also are improved remarkably. From the results, we showed the proposed new falling system is sufficiently safety and satisfies the KOSHA regulation through the numerical stress analysis. Also it is expected as the useful and effective safety device for workers.

유동성 악화에 따른 건설산업 위기극복 방안 모색을 위한 기초연구 (A Basic Study for Finding Methods to solve the Crisis of Construction Industry caused by Deterioration of Liquidity)

  • 김은성;이상효;김재준
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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    • pp.131-135
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    • 2009
  • Domestic construction industry is facing big difficulties by a worldwide financial crisis. Especially the deterioration of liquidity by the reject of banks for project financing and unsold housing project made a big problem on financing for the ongoing and new projects. To solve this, it is critical for construction companies. banking facilities and public organizations to cooperate and support each other. In this study, the methods which each part can do are investigated. Construction companies can do a price reduction, finance condition improvement for deposit and down payment, asset sale and cost reduction. And Public organizations can buy the assets of construction companies with proper price and ease the regulation to activate transactions of real estate. In the case of Banking facilities, they can support arrangement and liquidation of insolvent projects and so on.

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Load and Capacitor Stacking Topologies for DC-DC Step Down Conversion

  • Mace, Jules;Noh, Gwangyol;Jeon, Yongjin;Ha, Jung-Ik
    • Journal of Power Electronics
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    • 제19권6호
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    • pp.1449-1457
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    • 2019
  • This paper presents two voltage domain stacking topologies for powering integrated digital loads such as multiprocessors or 3D integrated circuits. Pairs of loads and capacitors are connected in series to form a stack of voltage domains. The voltage is balanced by switching the position of the capacitors in one case and the position of the loads in the other case. This method makes the voltage regulation robust to large differential load power consumption. The first configuration can be named the load stacking topology. The second configuration can be named the capacitor stacking topology. This paper aims at proposing and comparing these two topologies. Models of both topologies and a switching scheme are presented. The behavior, control scheme, losses and overall performance are analyzed and compared theoretically in simulation and experiments. Experimental results show that the capacitor stacking topology has better performance with a 30% voltage ripple reduction.

A Study on Annual Atmospheric Dispersion Factors Between Continuous and Purge Releases of Gaseous Radioactive Effluents

  • Kim, Na-Hyun;Hwang, Won-Tae;Kim, Chang-Lak
    • 방사성폐기물학회지
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    • 제19권2호
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    • pp.177-186
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    • 2021
  • Radioactive materials from nuclear power facilities can be released into the atmosphere through various channels. Recently, the dispersion of radioactive materials has become critical issue in Korea after Kori Unit 1 and Wolsong Unit 1 were permanently shut down. In this study, annual atmospheric dispersion factors were compared based on the continuous release and purge release using the XOQDOQ computer program, a method for calculating atmospheric dispersion factors at commercial nuclear power stations. The meteorological data analyzed in this study was based on the Shin Kori nuclear power meteorological tower which has the largest operating nuclear power plants in Korea, for three years (from 2008 to 2010). The analysis results of the dispersion factor of the radioactive material release obtained using the XOQDOQ program showed that the difference between the continuous release and purge release was within two times. This study will be valuable helpful for revealing the uncertainty of the predictive atmospheric dispersion factor to achieve regulation.