• 제목/요약/키워드: molecular processes

검색결과 1,250건 처리시간 0.031초

Indole-6-carboxaldehyde isolated from Sargassum thunbergii inhibits the expression and secretion of matrix metalloproteinase-9

  • Tae‑Hee Kim;Soo-Jin Heo;Seok-Chun Ko;Won Sun Park;Il-Whan Choi;Myunggi Yi;Won-Kyo Jung
    • International Journal of Molecular Medicine
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    • 제44권5호
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    • pp.1979-1987
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    • 2019
  • Sargassum thunbergii is a brown alga from which various bioactive compounds can be extracted. Among these, the activities of indole derivatives, particularly as potential inhibitors of matrix metalloproteinases (MMPs), and their underlying mechanisms have been rarely investigated. Therefore, we evaluated the inhibitory effects of indole-6-carboxaldehyde (I6CA) on MMP-9 by gelatin zymography and western blot anlaysis. We used phorbol 12-myristate 13-acetate (PMA), which is known to induce MMP-9 expression and secretion, to stimulate HT1080 cells. Our results revealed that I6CA significantly inhibited MMP-9 expression and secretion, without significantly affecting the viability of PMA-stimulated HT1080 cells. Our mechanistic studies indicated that I6CA suppressed the phosphorylation and activation of two mitogen-activated protein kinases (MAPKs), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase 1/2 (ERK). Furthermore, I6CA inhibited the phosphorylation of inhibitor of κBα (IκBα) in response to PMA stimulation, which suppressed nuclear factor-κB (NF-κB) p65 subunit nuclear translocation. Collectively, I6CA was determined to suppress MMP-9 expression and secretion, and effects were proposed to be mediated via the inhibition of the MAPK and NF-κB p65 pathways. Therefore, we suggested I6CA to be a potential therapeutic agent for MMP-9-related processes, including tumor invasion and metastasis; however, further investigation is required.

New Perspectives on Plant Defense Responses through Modulation of Developmental Pathways

  • Chung, Kwi-Mi;Igari, Kadunari;Uchida, Naoyuk;Tasaka, Masao
    • Molecules and Cells
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    • 제26권2호
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    • pp.107-112
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    • 2008
  • Invasion mechanisms of pathogens and counteracting defense mechanisms of plants are highly diverse and perpetually evolving. While most classical studies of plant defense have focused only on defense-specific factor-mediated responses, recent work is beginning to shed light on the involvement of non-stress signal components, especially growth and developmental processes. This shift in focus links plant resistance more closely with growth and development. In this review, we summarize our current understanding of how pathogens manipulate host developmental processes and, conversely, of how plants deploy their developmental processes for self-protection. We conclude by introducing our recent work on UNI, a novel R protein in Arabidopsis which mediates cross-talk between developmental processes and defense responses.

방전어기 KrF 레이저의 프라즈마 프로세서 해석 (Theoreitica1 analysis of plasma processes in discharge excited KrF laser)

  • 최부연;이주희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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    • pp.505-508
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    • 1989
  • A computer simulation code of UV preionized discharge KrF laser is developed, including time dependent circuit equations, boltzmann equations, and plasma kinetic equations for various atomic and molecular species. Rate constants for electron collision processes are calculated with a boltzmann equations as a function of E/N. In this study, we studied mainly the $KrF^*$ formation process, relaxation process, and the 248nm absorption process as a function of charging voltage.

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Study of rganized Assemblies and Surfaces Using Picosecond Lasers

  • Bhattacharyya, Kankan
    • Journal of Photoscience
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    • 제6권3호
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    • pp.123-128
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    • 1999
  • Dynamics of many ultrafast processes are markedly slowed down in various organized molecular assemblies compared to ordinary liquids. We will show that the solvation dynamics of water molecules is affected amost dramatically and is retarded by 3 ∼4 orders of magnitude in microemulsions, micells and lipids. We will also discuss how the access to fewer water molucules and the drastically altered local pH in an organized asembly affected the excited state proton transfer processes. Finally, we will show how surface second haromonic generation can be used to study the air-water surface.

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Investigation of Molecular Coupling Effects on Photothermal Properties of Polar Solutions by Thermal Lens

  • 하정현;임종태;최중길;김용록
    • Bulletin of the Korean Chemical Society
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    • 제17권8호
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    • pp.682-685
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    • 1996
  • Photothermal properties depend on the characteristics of energy transfer processes in solution. In this study, a time-resolved single beam thermal lens experiment in various solvents is employed to investigate the energy coupling effects which govern the energy transfer processes. Interestingly, it is observed that the behaviour of the photothermal propagation in solution depends on the property of solution and the concentration of solute in a single beam thermal lens configuration. These characteristics lead us to consider the solute-solvent coupling effects as well as the solvent-solvent interactions.

Large Conformational Changes and Molecular Recognition in Signal Transduction: Calmodulin and Active Transport/Chemosensory Receptors

  • QUIOCHO, FLORANTE A.
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1997년도 학술발표회
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    • pp.9-10
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    • 1997
  • Calmodulin: very large conformation change of helix uncoiling, hinge-bending and domain rotation. Calmodulin (CaM) is the principal Ca$\^$2+/ -dependent regulator of a variety of important eukaryotic cellular processes. In many of these processes, calmodulin activates a plethora of target enzymes, and the calmodulin-binding domains in several targets have been shown to residue in a region of about 18-residue peptide segment.(omitted)

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AAPH를 이용한 아세트산비닐의 유화중합 (Emulsion Polymerization of Vinyl Acetate Using AAPH)

  • Kwak, Jin-Woo;Kim, Joon-Ho;Lyoo, Won-Seok
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 봄 학술발표회 논문집
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    • pp.13-16
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    • 2003
  • Vinyl acetate monomer can be polymerized through bulk, solution, emulsion, and suspension polymerization processes. However, in the preparation of PVA from bulk or solution polymerization, there are several technical limitations for obtaining high yield and high molecular weight simultaneously. Thus, the improvement of polymerization method is necessary to prepare the PVA with high yield and high molecular weight because that the difficulty in control of high viscosity and in removal of the heat of polymerization, which might lead to side reactions like branching. (omitted)

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Linear Eddy Model을 이용한 스칼라의 혼합특성 해석 (Analysis for Scalar Mixing Characteristics using Linear Eddy Model)

  • 김후중;김용모;안국영
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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    • pp.133-137
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    • 2004
  • The present study is focused on the small scale turbulent mixing processes in the scalar field. In order to deal with molecular mixing in turbulent flow, the linear eddy model is addressed. In each realization, the molecular mixing term is implemented deterministically, and turbulent stirring is represented by a sequence of instantaneous, statistically independent rearrangement event called by triplet map. The LEM approach is applied with relatively simple conditions. The characteristics of scalar mixing and PDF profiles are addressed in detail.

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시냅스 가소성에 관한 고찰 (Review of Synaptic Plasticity)

  • 김석범;김진상
    • The Journal of Korean Physical Therapy
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    • 제13권1호
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    • pp.229-235
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    • 2001
  • Clinical interest has lately been roused by evidence that comprehension of synaptic plasticity may be based on the theoretical opinion. This paper describes perception of synaptic plasticity. Especially processes of long term potentiation(LTP) and long term depression(LTD) are discussed. Recently, it is assessed to genetical parts from development of molecular biology. Therefore this review also represents aspect of molecular events of synaptic plasticity.

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Molecular Aspects of Some Photobiological Receptors

  • Song, Pill-Soon
    • Applied Biological Chemistry
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    • 제20권1호
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    • pp.10-25
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    • 1977
  • The photobiological receptors of phototactic, phototropic, and photomorphogenic responses of various organisms have been described in terms of spectroscopic, photophysical and photochemical properties which may be relevant in elucidating the energy transduct ion mechanism(s) in photobiology. The photoreceptors discussed include carotenoids, flavins, stentorin and phytochrome. Although the molecular modes of their photobiological action still remain largely unexplained, it is possible to suggest several primary molecul ar processes of the photoreceptors in eliciting responses of various organisms to light.

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