• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.107-107
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• 2001

In the present study, the protective effect of Scutellaria baicalensis against DNA damage in HL-60 cells exposed to $^{60}$ Co ${\gamma}$-rays was evaluated using micronuclei formation and alkaline single cell gel electrophoresis (SCGE, comet assay). The frequency of micronuclei was decreased in groups treated with water extract (P＜0.01), polysaccaride fraction (P＜0.01) and methanol fraction (P＜0.01) before/after exposure to 200 cGy of ${\gamma}$-rays.(omitted)

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.100-104
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• 2002

Serratia marcescens biovar A2/A6, isolated from an Indonesian freshwater source, was identified based on extensive morphological, biochemical and genetic characterization. Formation of pigment was found to be strongly influenced by environmental conditions. Placket-Burman design was used to analyze the effect of carbon and nitrogen sources. Based on results of physiological and biochemical studies, the optimum conditions for growth and pigment formation were incubation 30$^{\circ}C$ in a neutral to slightly alkaline medium containing lactic acid and beef extract.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.167-170
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• 2005

The mechanism of striation in the coplanar- and matrix-type plasma display panel (PDP) cells has been studied using the particle-in-cell Monte-Carlo Collision (PIC-MCC) model. The striation formation is related to the ionization energy of neutral atoms and the well-like deformation of space potential by space charge distribution. Negative wall charge accumulation by electrons on the MgO surface of the anode region is also one of the key factors for the formation of striation. The clearness of the striation phenomenon in PIC-MCC code in comparison with fluid code can be explained by using nonlocal electron kinetic effect.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.599-607
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• 1996

Acetylarsonate was prepared for testing antitumor and immunological effects. It showed cytotoxicity directly on Sarcoma 180. L1210 and MOLT-4 by MTT assay. It did not seemed to trigger the mitosis of human lymphocytes in culture, but that showed the cytotoxicity with higher dose. The rosette formation and spleen weight of mouse which acetylarsonate was administered to for 2 weeks were increased. Furthermore, peripheral helper T- and cytotoxic/suppressor T-lymphocytes were increased in acetylarsonate-injected-mice significantly when it was estimated with simultaneous 2 color analysis using anti Lyt2-FITC and L3T4-PE monoclonal antibody by Flow cytometer.

• Journal of Society of Preventive Korean Medicine
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• v.10 no.2
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• pp.19-30
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• 2006

It is well known that glucocorticoid may induce osteoporosis as its side effect in long-term therapy. The inhibition of osteoblast by glucocorticoid is also recognized as its action mechanism of decreased bone formation. In this study, the effect of DSG, Danchisoyosangamibang, on the differentiation and function of osteoblastic cells was investigated. The osteoblastic cells were isolated from rat calvariae using collagenase treatment. The cell counting, enzyme activity assay, MTT assay, collagen content assay were done to determine the cell proliferation, intracellular alkaline phosphatase (ALP) activity, bone martrix production, and cell apoptosis. DSG enhanced the cell proliferation after the culture for 10 days. ALP activity and total protein synthesis, and intracelluar collagen synthesis were increased time dependently when the cells were treated with DSG in the presence of dexamethasone. And, DSG restored calvarial cell function decreased by dexamethasone.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.18-18
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• 2002

This study was to investigate the effect of neurotrophic factors on neural cell differentiation in vitro derived from human embryonic stem (hES, MB03) cells. For neural progenitor cell formation derived from hES cells, we produced embryoid bodies (EB: for 5 days, without mitogen) from hES cells and then neurospheres (for 7 - 10 days, 20 ng/㎖ of bFGF added N2 medium) from EB. And then finally for the differentiation into mature neuron cells, neural progenitor cells were cultured in ⅰ) N2 medium (without bFGF), ⅱ) N2 supplemented with brain derived neurotrophic factor (BDNF, 5ng/㎖) or ⅲ) N2 supplemented with platelet derived growth factor-bb (PDGF-bb, 20ng/㎖) for 2 weeks. (omitted)

• IMMUNE NETWORK
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• v.12 no.3
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• pp.71-83
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• 2012

T cell activation and function require physical contact with antigen presenting cells at a specialized junctional structure known as the immunological synapse. Once formed, the immunological synapse leads to sustained T cell receptor-mediated signalling and stabilized adhesion. High resolution microscopy indeed had a great impact in understanding the function and dynamic structure of immunological synapse. Trends of recent research are now moving towards understanding the mechanical part of immune system, expanding our knowledge in mechanosensitivity, force generation, and biophysics of cell-cell interaction. Actin cytoskeleton plays inevitable role in adaptive immune system, allowing it to bear dynamic and precise characteristics at the same time. The regulation of mechanical engine seems very complicated and overlapping, but it enables cells to be very sensitive to external signals such as surface rigidity. In this review, we focus on actin regulators and how immune cells regulate dynamic actin rearrangement process to drive the formation of immunological synapse.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1503-1507
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• 2013

The two major symptoms characterizing Alzheimer's disease are the formation of amyloid-${\beta}$ extracellular deposits in the form of senile plaques and intracellular neurofibrillary tangles (NFTs) that consist of pathological hyperphosphorylated tau protein aggregated into insoluble paired helical filaments (PHFs). Neurons of the central nervous system have appreciable amounts of tau protein, a microtubule-associated protein. To maintain an optimal operation of nerves, the microtubules are stabilized, which is necessary to support cell structure and cellular processes. When the modified tau protein becomes dysfunctional, the cells containing misfolded tau cannot maintain cell structure. One of the pathological hallmarks of Alzheimer's disease is hyperphosphorylated tau protein. This paper shows that the small heat shock protein from humans (Hsp27) reduces hyperphosphorylated tau and prevents hyperphosphorylated tau-induced cell death of the human neuroblastoma cell line SH-SY5Y.

• Journal of Society of Preventive Korean Medicine
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• v.12 no.2
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• pp.197-206
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• 2008

The inhibition of osteoblast by glucocorticoid is recognized as its action mechanism of decreased bone formation. In this study, the effect of JY, Jahyulyangkeuntang, on the differentiation and mineralization of osteoblastic cells was investigated in the presence of dexamethasone. The cell counting, enzyme activity assay, MTT assay, collagen content assay were done to determine the cell proliferation, alkaline phosphatase(ALP) activity, bone martrix production, and cell apoptosis. JY enhanced the cell proliferation after the culture for 10 days. ALP activity and total protein synthesis, and intracellular collagen synthesis were increased when the cells were treated with JY. And JY restored calvarial cell function decreased by dexamethasone.

• Molecules and Cells
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• v.39 no.7
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• pp.515-523
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• 2016

Long-term immunity to many viral and bacterial pathogens requires$ CD8^+$ memory T cell development, and the induction of long-lasting$ CD8^+$ memory T cells from a $na{\ddot{i}}ve$, undifferentiated state is a major goal of vaccine design. Formation of the memory$ CD8^+$ T cell compartment is highly dependent on the early activation cues received by $na{\ddot{i}ve}$ $CD8^+$ T cells during primary infection. This review aims to highlight the cellularity of various niches within the lymph node and emphasize recent evidence suggesting that distinct types of T cell activation and differentiation occur within different immune contexts in lymphoid organs.