• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.313-318
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• 2008

An enantioselective ring opening of racemic terminal epoxides has been achieved by using heterobimetallic cobalt salen complexes with variety of nucleophiles. They were proven to be highly enantioselective and reactive for the synthesis of valuable chiral building blocks in enantio-riched forms up to 98% ee.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.543-546
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• 1989

The photocycloaddition reaction of khellin with several olefins has been investigated. The photocycloadducts are formed regioselectively on furanyl 4',5'-double bond of khellin probably due to the localization of excitation energy on the furanyl 4',5'-double bond in the reactive excited state. The photocycloaddition reaction proceeds through the excited triplet state and the same product was formed when khellin is irradiated with dimethylfumarate or dimethylmaleate indicating the formation of common intermediate. The quantum yields of photocycloadduct formation, fluorescence, and intersystem crossing are very sensitive to proton-donating ability of solvents.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.210.1-210.1
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• 2003

In this study, we investigated the effect of inhibition of proliferation and antioxidant effect on B16F10 murine melanoma cell. Also, we examined by MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and intracellular reactive oxygen intermediate levels and the levels of catalase(CAT), superoxide dismutase (SOD), and glutathione peroxidase(GPX) an adaptive response of oxidative stress on B16F10 murine melanoma cell of pretreated with hydrogen peroxide. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.159.3-160
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• 2003

It has been known that quercetin is one of bioflavonid compounds and has anti-tumor effect by suppressing tumor growth in vitro and in vivo, including multiple biological effects by antioxidant and effective anti-inflammatory agent. The present study investigated whether quercetin can enhance antioxidant enzyme activity (glutathione proxidase: GPX, superoxide dismutase: SOD, catalase: CAT) and regulate the intracellular reactive oxygen intermediate levels on the B16F10 murine melanoma cells in the presensece of vitamin E, L-ascorbic acid (vitamin C) and reduced glutathione (GSH). (omitted)

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.285-296
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• 1997

Injury to brain transforms resting astrocytes to their reactive form, the hallmark of which is an increase in glial fibrillary acidic protein (GFAP), the major intermediate filament protein of their cell type. The overall glial response after brain injury is referred to as reactive gliosis. Glial-neuronal interaction is important for neuronal migration, neurite outgrowth and axonal guidance during ontogenic development. Although much attention has been given to glial regulation of neuronal development and regeneration, evidences also suggest a neuronal influence on glial cell differentiation, maturation and function. The aim of the present study was to analyze the effects of glial-hippocampal neuronal co-culture on GFAP expression in the co-cultured astrocytes. The following antibodies were used for double immunostaining chemistry; mouse monoclonal antibodies for confirm neuronal cells, rabbit anti GFAP antibodies for confirm astrocytes. Primary cultured astrocytes showed the typical flat polygonal morphology in culture and expressed strong GFAP and vimentin. Co-cultured hippocampal neurons on astrocytes had phase bright cell body and well branched neurites. About half of co-cultured astrocytes expressed negative or weak GFAP and vimentin. After 2 hour glutamate (0.5 mM) exposure of glial-neuronal co-culture, neuronal cells lost their neurites and most of astrocytes expressed strong CFAE and vimentin. In Western blot analysis, total GFAP and vimentin contents in co-cultured astrocytes were lower than those of primary cultured astrocytes. After glutamate exposure of glial-neuronal co-culture, GFAP and vimentin contents in astrocytes were increased to the level of primary cultured astrocytes. These results suggest that neuronal cell decrease GFAP expression in co-cultured astrocytes and hippocampal neuronal-glial co-culture can be used as a reactive gliosis model in vitro for studying GFAP expression of astrocytes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.3-6
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• 2009

Aluminum nitride (AIN) thin films were deposited on a polycrystalline 3C-SiC intermediate layer by a pulsed reactive magnetron sputtering system. Characteristics of the AIN/SiC heterostructures were investigated by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The columnar structure of AIN thin films was observed by FE-SEM. The surface roughness of AlN films on the 3C-SiC buffer layer was measured using AFM. The XRD pattern of AlN films on SiC buffer layers was highly oriented at (002). Full width at half maximum (FWHM) of the rocking curve near (002) reflections was $1.3^{\circ}$. The infrared absorbance spectrum indicated that the residual stress of AIN thin films grown on SiC buffer layers was nearly negligible. The 3C-SiC intermediate layers are promising for the realization of nitride based electronic and mechanical devices.

• Korean Journal of Community Nutrition
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• v.15 no.6
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• pp.796-805
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• 2010

This study investigated the correlations and risk distribution differences between high sensitivity C-reactive protein (hs-CRP) and the diagnosis factors of metabolic syndrome among the residents of a rural community. Two thousand adults aged from 40 to 70 were recruited and 1,968 subjects were included in the study after excluding those with infectious disease or with hs-CRP higher than 10 mg/L in blood. The subjects were then divided into three groups of hs-CRP to examine the correlations and risk ratio with the risk factors of metabolic syndrome. There was a tendency of hs-CRP increasing according to the number of risk factors of metabolic syndrome. The risk ratio with hs-CRP according to metabolic syndrome significantly increased by 2.0 and 2.2 times in the intermediate and high risk group, respectively, compared with the low risk group. The risk ratio with the risk factors of metabolic syndrome according to hs-CRP rose in abdominal obesity, triglyceride, and W/Ht in the intermediate risk group of hs-CRP. The risk ratio also surged in high pressure, W/Ht, ex-drinking (1.7 times), exsmoking (2.0 times) and current smoking (2.0 times) in the high risk group. The results indicate that hs-CRP is related to the risk factors of metabolic syndrome and that it's very important to manage obesity including abdominal obesity and W/Ht and everyday habits including drinking and smoking.

• Research in Community and Public Health Nursing
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• v.20 no.2
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• pp.143-151
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• 2009

Purpose: This study was to investigate the relations and odds ratio between hs-CRP and the risk factors of metabolic syndrome according to glucose intolerance and diabetes among the residents of a rural community. Methods: The subjects include 1,968 adults aged from 40 to 70 who were divided into four groups and a diabetes group according to glucose intolerance to compare the relations and risk ratio between hs-CRP and the risk factors of metabolic syndrome. Results: The results reveal that the greater the subjects' glucose intolerance was, the higher their hs-CRP became and the more risk factors of metabolic syndrome they had. The impaired glucose tolerance group showed 1.7 times higher blood pressure than the control group. The diabetes group showed a high odds ratio with 2.3 times higher blood pressure, 2.2 times higher abdominal obesity, and 2.4 times higherW/Ht than the control group. And the odds ratio increased significantly by 1.7 times in the hs-CRP intermediate risk group and 2.5 times in the high risk group compared with the control group. Conclusion: Considering the study results, it is very important to monitor abdominal obesity, blood pressure and the intermediate and high risk group of hs-CRP in order to reduce the contraction of cardiovascular diseases.

• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.13-20
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• 2022

Basically Mobile Ad Hoc Network (MANET) is an autonomous system with the collection of mobile nodes, these nodes are connected to each other by using wireless networks. A mobile ad hoc network poses this quality which makes topology in dynamic manner. As this type of network is Ad Hoc in nature hence it doesn't have fixed infrastructure. If a node wishes to transfer data from source node to a sink node in the network, the data must be passed through intermediate nodes to reach the destination node, hence in this process data packet loss occurs in various MANET protocols. This research study gives a comparison of various Mobile Ad Hoc Network routing protocols like proactive (DSDV) and reactive (AODV, DSR) by using random topology with more intermediate nodes using CBR traffic. Our simulation used 50, 100, and 150 nodes variations to examine the performance of the MANET routing protocols. We compared the performance of DSDV, AODV and DSR, MANET routing protocols with the result of existing protocol using NS-2 environment, on the basis of different performance parameters like Packet Delivery Ratio, average throughput and average end to end delay. Finally we found that our results are better in terms of throughput and packet delivery ratio along with low data loss.

• BMB Reports
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• v.45 no.3
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• pp.147-152
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• 2012

Methylglyoxal (MG) was identified as an intermediate in non-enzymatic glycation and increased levels were reported in patients with diabetes. In this study, we evaluated the effects of MG on the modification of ferritin. When ferritin was incubated with MG, covalent crosslinking of the protein increased in a time- and MG dose-dependent manner. Reactive oxygen species (ROS) scavengers, $N-acetyl-_L-cysteine$ and thiourea suppressed the MG-mediated ferritin modification. The formation of dityrosine was observed in MG-mediated ferritin aggregates and ROS scavengers inhibited the formation of dityrosine. During the reaction between ferritin and MG, the generation of ROS was increased as a function of incubation time. These results suggest that ROS may play a role in the modification of ferritin by MG. The reaction between ferritin and MG led to the release of iron ions from the protein. Ferritin exposure to MG resulted in a loss of arginine, histidine and lysine residues. It was assumed that oxidative damage to ferritin caused by MG may induce an increase in the iron content in cells, which is deleterious to cells. This mechanism, in part, may provide an explanation or the deterioration of organs under diabetic conditions.