• Title/Summary/Keyword: Activation Process

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Ginsenoside Rh2 Induces Apoptosis via Activation of Caspase-1 and -3 and Up-Regulation of Bax in Human Neuroblastoma

  • Kim, Young-Soak;Jin, Sung-Ha
    • Archives of Pharmacal Research
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    • v.27 no.8
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    • pp.834-839
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    • 2004
  • In human neuroblastoma SK-N-BE(2) cells undergoing apoptotic death induced by ginsenos-ide Rh2, a dammarane glycoside that was isolated from Panax ginseng C. A. Meyer, caspase-1 and caspase-3 were activated. The expression of Bax was increased in the cells treated with ginsenoside Rh2, whereas Bcl-2 expression was not altered. Treatment with caspase-1 inhibi-tor, Ac-YVAD-CMK, or caspase-3 inhibitor, Z-DEVD-FMK, partially inhibited ginsenoside Rh2-induced cell death but almost suppressed the cleavage of the 116 kDa PARP into a 85 kDa fragment. When the levels of p53 were examined in this process, p53 accumulated rapidly in the cells treated early with ginsenoside Rh2. These results suggest that activation of caspase-1 and -3 and the up-regulation of Bax are required in order for apoptotic death of SK-N-BE(2) cells to be induced by ginsenoside Rh2, and p53 plays an important role in the pathways to promote apoptosis.

Glia as a Link between Neuroinflammation and Neuropathic Pain

  • Jha, Mithilesh Kumar;Jeon, Sang-Min;Suk, Kyoung-Ho
    • IMMUNE NETWORK
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    • v.12 no.2
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    • pp.41-47
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    • 2012
  • Contemporary studies illustrate that peripheral injuries activate glial components of the peripheral and central cellular circuitry. The subsequent release of glial stressors or activating signals contributes to neuropathic pain and neuroinflammation. Recent studies document the importance of glia in the development and persistence of neuropathic pain and neuroinflammation as a connecting link, thereby focusing attention on the glial pathology as the general underlying factor in essentially all age-related neurodegenerative diseases. There is wide agreement that excessive glial activation is a key process in nervous system disorders involving the release of strong pro-inflammatory cytokines, which can trigger worsening of multiple disease states. This review will briefly discuss the recent findings that have shed light on the molecular and cellular mechanisms of glia as a connecting link between neuropathic pain and neuroinflammation.

Apoptotic Signaling Pathways: Caspases and Stress-Activated Protein Kinases

  • Cho, Ssang-Goo;Choi, Eui-Ju
    • BMB Reports
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    • v.35 no.1
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    • pp.24-27
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    • 2002
  • Apoptotic cell death is an active process mediated by various signaling pathways, which include the caspase cascade and the stress-activated protein kinase pathways. The caspase cascade is activated by two distinct routes: one from cell surface and the other from mitochondria. Activation of the route from cell surface requires the cellular components that include membrane receptors, adaptor proteins such as TRADD and FADD, and caspase-8, while activation of the other from mitochondria requires Apaf-1, caspase-9, and cytosolic cytochrome c. On the other hand, persistent stimulation of the stress-activated protein kinase pathway is also shown to mediate apoptosis in many cell types. Gene-targeting studies with jnk- or jip-null mice, in particular, strongly suggest that this signaling pathway plays a pivotal role in the cellular machinery for apoptosis.

Roles of YAP in mediating endothelial cell junctional stability and vascular remodeling

  • Choi, Hyun-Jung;Kwon, Young-Guen
    • BMB Reports
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    • v.48 no.8
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    • pp.429-430
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    • 2015
  • Angiogenesis is a complex process involving dynamic interaction of various cell to cell interactions. Endothelial cell interactions regulated by growth factors, inflammatory cytokines, or hemodynamic stress are critical for balancing vascular quiescence and activation. Yes-associated protein (YAP), an effector of Hippo signaling, is known to play significant roles in maintaining cellular homeostasis. However, its role in endothelial cells for angiogenic regulation remains relatively unexplored. We demonstrated the critical role of YAP in vascular endothelial cells and elucidated the underlying molecular mechanisms involved in angiogenic regulation of YAP. YAP was expressed in active angiogenic regions where endothelial cell junctions were relatively loosened. Consistently, YAP subcellular localization and activity were regulated by VE-cadherin-mediated PI3K/Akt pathway. YAP thereby regulated endothelial sprouting via angiopoietin-2 expression. These results provide an insight into a model of coordinating endothelial junctional stability and angiogenic activation through YAP. [BMB Reports 2015; 48(8): 429-430]

Factors Influencing Satellite Cell Activity during Skeletal Muscle Development in Avian and Mammalian Species

  • Nierobisz, Lidia S;Mozdziak, Paul E
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.3
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    • pp.456-464
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    • 2008
  • Avian and mammalian skeletal muscles exhibit a remarkable ability to adjust to physiological stressors induced by growth, exercise, injury and disease. The process of muscle recovery following injury and myonuclear accretion during growth is attributed to a small population of satellite cells located beneath the basal lamina of the myofiber. Several metabolic factors contribute to the activation of satellite cells in response to stress mediated by illness, injury or aging. This review will describe the regenerative properties of satellite cells, the processes of satellite cell activation and highlight the potential role of satellite cells in skeletal muscle growth, tissue engineering and meat production.

Effects of carbonization temperature on pore development in polyacrylonitrile-based activated carbon nanofibers

  • Lee, Hye-Min;An, Kay-Hyeok;Kim, Byung-Joo
    • Carbon letters
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    • v.15 no.2
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    • pp.146-150
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    • 2014
  • In this work, activated carbon nanofiber (ACNF) electrodes with high double-layer capacitance and good rate capability were prepared from polyacrylonitrile nanofibers by optimizing the carbonization temperature prior to $H_2O$ activation. The morphology of the ACNFs was observed by scanning electron microscopy. The elemental composition was determined by analysis of X-ray photoelectron spectroscopy. $N_2$-adsorption-isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller and Dubinin-Radushkevich equations. ACNFs processed at different carbonization temperatures were applied as electrodes for electrical double-layer capacitors. The experimental results showed that the surface morphology of the CNFs was not significantly changed after the carbonization process, although their diameters gradually decreased with increasing carbonization temperature. It was found that the carbon content in the CNFs could easily be tailored by controlling the carbonization temperature. The specific capacitance of the prepared ACNFs was enhanced by increasing the carbonization temperature.

High Temperature properties of Mechanically Alloyed Al-Ni System (기계적 합금법으로 제조된 Al-Ni 합금계의 고온특성)

  • 김유영
    • Journal of Powder Materials
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    • v.1 no.1
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    • pp.35-41
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    • 1994
  • Mechanical alloying process of Al-8wt.% Ni powder was investigated for the various milling time in order to get the steady state powder. High temperature deformation behaviors of the sintered specimens were investigated by activation energy calculated after high temperature compression tests at the strain rates of 2.5$\times$10-3 s-1, 2.5$\times$10-2 s-1 and 2.5$\times$10-1 s-1 at the temperature range between $350^{\circ}C$ and $450^{\circ}C$. The steady state was obtained after 1000 minutes of milling with the PCA of 1.5 wt.% stearic acid under the condition of grinding media to powder weight ratio of 50 : 1 and impeller rotating speed of 300 rpm. True activation energy of Al-8wt.% Fe alloy was estimated to be 181 kJ/mole at the temperature range of 350~ $400^{\circ}C$ and 265 kJ/mole at the range of 400~$450^{\circ}C$.

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Self-organizing Networks with Activation Nodes Based on Fuzzy Inference and Polynomial Function (펴지추론과 다항식에 기초한 활성노드를 가진 자기구성네트윅크)

  • 김동원;오성권
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.15-15
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    • 2000
  • In the past couple of years, there has been increasing interest in the fusion of neural networks and fuzzy logic. Most of the existing fused models have been proposed to implement different types of fuzzy reasoning mechanisms and inevitably they suffer from the dimensionality problem when dealing with complex real-world problem. To overcome the problem, we propose the self-organizing networks with activation nodes based on fuzzy inference and polynomial function. The proposed model consists of two parts, one is fuzzy nodes which each node is operated as a small fuzzy system with fuzzy implication rules, and its fuzzy system operates with Gaussian or triangular MF in Premise part and constant or regression polynomials in consequence part. the other is polynomial nodes which several types of high-order polynomials such as linear, quadratic, and cubic form are used and are connected as various kinds of multi-variable inputs. To demonstrate the effectiveness of the proposed method, time series data for gas furnace process has been applied.

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Allograft Immune Reaction of Kidney Transplantation Part 1. Mechanism of Allograft Rejection (신이식 후 면역반응의 이해 - 1부. 이식 거부 반응의 기전 -)

  • Kang, Hee-Gyung
    • Childhood Kidney Diseases
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    • v.12 no.1
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    • pp.23-29
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    • 2008
  • Kidney allograft transplantation is the most effective method of renal replacement for end stage renal disease patients. Still, it is another kind of 'disease', requiring immunosuppression to keep the allograft from rejection(allograft immune reaction). Immune system of the allograft recipient recognizes the graft as a 'pathogen (foreign or danger)', and the allograft-recognizing commanderin-chief of adaptive immune system, T cell, recruits all the components of immune system for attacking the graft. Proper activation and proliferation of T cell require signals from recognizing proper epitope(processed antigen by antigen presenting cell) via T cell receptor, costimulatory stimuli, and cytokines(IL-2). Thus, most of the immunosuppressive agents suppress the process of T cell activation and proliferation.

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Selective Activation of Mitogen-Activated Protein (MAP) Kinase During the Progression of Renal Disease

  • Park, Sang-Joon;Jeong, Kyu-Shik;Jeong, Tae-Sook;Bok, Song-Hae;Lee, Cha-Soo
    • Proceedings of the Korean Society of Veterinary Pathology Conference
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    • 2000.09a
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    • pp.19-19
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    • 2000
  • Most renal diseases progress by consecutive cell responses such as hypertrophy, hyperplsia, proliferation, defferentiation, sclerosis, fibrosis and other cellular degenerative process. These cellular responses are mediated by the activation of various mitogens such as vasoconstrictors, growth factors, hormone, genotoxins and cytokines through mechanical, hemodynamic, immunological injury as well as metabolic abnormality. (omitted)

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