• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.131-135
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• 2000

In order to investigate the origin of capacity fading with charge/discharge cycling in $LiMn_2O_4$ thin film battery, impedance studies have been performed with increasing cycling in $LiMn_2O_4/1M\;LiClO_4-PC/Li$ cells. The fitted values obtained from impedance data show good agreements with the experimental results. Especially, the element of charge transfer resistance of $LiMn_2O_4/liquid$ electrolyte interface initially increased, and then saturated with increasing the charge/discharge cycles, which could explain the cause of initial abrupt capacity fading of $LiMn_2O_4$ thin film with cycling due to interfacial reaction. The steady capacity fading is caused by the increasing of Warburg resistance. The chemical diffusion coefficient of Li ions decreased from $5.15\times10^{-11}cm^2/sec$ at 1st cycles to $6.3\times10^{-12}cm^2/sec$ at 800th cycles, which attributed to the Jahn-Teller distortion/Mn dissolution which diminishes tetra hedral sites necessary for Li diffusion in $LiMn_2O_4$.

• Food Science and Preservation
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• v.18 no.3
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• pp.358-365
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• 2011

The antioxidant and neuronal cell-protective effects of hot water extract from commercial buckwheat tea (CBTE) were evaluated. The 2,2'-azino-bis(3-ethyl-benzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP), and malondialdehyde (MDA) inhibitory effect of the CBTE increased in a dose-dependent manner. The Intracellular reactive oxygen species (ROS) accumulation that resulted from hydrogen peroxide ($H_2O_2$) treatment more significantly decreased when CBTE was present in the media than when the PC12 cells were treated only with $H_2O_2$. In the neuronal cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT), the aqueous extracts showed a protective effect against $H_2O_2$-induced neurotoxicity, and the lactate dehydrogenase (LDH) release into the medium was also inhibited by CBTE. The total phenolics of CBTE was 9,608.10 mg/100 g, and the major phenolic compounds were rutin (13.42 mg/100 g) and quercitrin (0.90 mg/100 g). These data suggested that CBTE, including the aforementioned phenolics, may be useful in reducing the risk of neurodegenerative disease.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1034-1038
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• 1995

The purpose of this study is to research and develop $TiS_2$ composite cathode for lithium polymer battery(LPB). $TiS_2$ electrode represent a class of insertion positive electrode used in Li secondary batteries. In this study, we investigated preparation of $TiS_2$ composite cathode and AC impedance response of $TiS_2$ composite/SPE/Li cells as a function of state of charge(SOC) and cycling. The resistance of B type cell using $TiS_2PEO_8LiClO_4PC_5EC_5$ composite cathode was lower than that of A type cell using $TiS_2PEO$ composite cathode. The cell resistance of B type cell is high for the first few percent discharge, decreases for midium discharge and then increases again toward the end of discharge. We believe the magnitude of the cell resistance is dominated by passivation layer impedance and small cathode resistance. AC impedance results indicate that the cell internal resistance increase with cycling, and this is attributed to change of passivation layer impedance with cycling. The passivation layer resistance($R_f$) of B type cell decreases for the 2nd cycling and then increases again with cycling. Redox coulombic efficiency of B type cell was about 141% at 1st cycle and 100% at 12th cycle. Also, $TiS_2$ specific capacity was 115 mAh/g at 12 cycle.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.445-452
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• 2014

The purpose of this study was to investigate the therapeutic effects of DA-9801, an optimized extract of Dioscorea species, on diabetic peripheral neuropathy in a type 2 diabetic animal model. In this study, db/db mice were treated with DA-9801 (30 and 100 mg/kg, daily, p.o.) for 12 weeks. DA-9801 reduced the blood glucose levels and increased the withdrawal latencies in hot plate tests. Moreover, it prevented nerve damage based on increased nerve conduction velocity and ultrastructural changes. Decrease of nerve growth factor (NGF) may have a detrimental effect on diabetic neuropathy. We previously reported NGF regulatory properties of the Dioscorea genus. In this study, DA-9801 induced NGF production in rat primary astrocytes. In addition, it increased NGF levels in the sciatic nerve and the plasma of type 2 diabetic animals. DA-9801 also increased neurite outgrowth and mRNA expression of Tieg1/Klf10, an NGF target gene, in PC12 cells. These results demonstrated the attenuation of diabetic peripheral neuropathy by oral treatment with DA-9801 via NGF regulation. DA-9801 is currently being evaluated in a phase II clinical study.

• Journal of Oriental Neuropsychiatry
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• v.20 no.2
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• pp.111-120
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• 2009

Objectives : This study was performed to investigate the effects of Needle Electrode Electrical Stimulation (NEES) on ischemia-induced cerebrovascular accidents. After obstruction and reperfusion of ${\ast}{\ast}$ arteries in white mice, the amounts of necrosis and inflammation related substances IL-6, Caspase-3, and PARP, C-fos were measured in neurons of the hippocampus. The following results were obtained. Methods : This study used 21 male specific pathogen free (SPF) SD (Sprague Dawley) rats, 8 weeks of age and approximately 300 g in weight, that were given at least 1 week to adapt to the lab environment Each exposed artery was completely occluded with non-absorbent suture thread and kept in that state for 5 minutes. The sutures were then removed to allow reperfusion of blood. Test group is control group for comparison with the common carotid artery occlusion models, a GI group that underwent common carotid artery occlusion, and a needle electrode electrical stimulation (NEES) group that underwent NEES after artery occlusion. The GI and NEES groups were given 12, 24, or 48 hours of reperfusion before NEES. NEES device (PG6, ITO, Japan, 9V, current, 2Hz) was used to stimulate the right and left acupoint ST36 of the SD rats for 30 minutes while they were sedated with 3% isoflurane. An immunohistochemistry test was done on the forebrains of the GI induced rats. All the data collected from this study was symbolized and analyzed using a statistics processing program (SPSS 12.0K/PC). The level of significance was set at ${\alpha}$=0.05 and a T-TEST analysis was used to find out the effects of treatment on each of the groups: the normal group, the CVA induced group, and the treatment after CVA induction group. Results : Both PARP and C-fos immuno-reactive cells, related to apoptosis, were greater in the GI groups than the NEES group. Caspase and IL-6 immuno-reactive cells, related to inflammation, were greater in the GI and NEES groups than the control group. Conclusions : This research was conducted to study the effects of NEES on CVA due to ischemia. Occlusion and reperfusion was performed on the common carotid arteries of white rats, after which amounts of substances related to neuron necrosis and inflammation - PARP, IL-6, Caspase-3, and C-fos - were measured in the Hippocampus

• The Journal of Korean Obstetrics and Gynecology
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• v.32 no.3
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• pp.32-56
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• 2019

Objectives: The purpose of this study was to investigate the in vitro anti-inflammatory, anti-pruritic and antimicrobial effects of the three herbal prescription (EST, SCT, WDT), which has been traditionally used for treating leukorrhea induced by various infections in the female genital tract. Methods: In this experiment, the anti-inflammatory effects were evaluated by Nitric oxide (NO), $Interlukine-1{\beta}$ ($IL-1{\beta}$), Interlukine-2 (IL-2), Interlukine-6 (IL-6), Tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), Prostaglandin $E_2$ ($PGE_2$), Leukotriene $B_4$ ($LTB_4$) production amount and Inducible nitric oxide synthase (iNOS), Nuclear factor kappa B ($NF-{\kappa}B$), Cyclooxygenase-2 (COX-2) gene expression levels in RAW264.7 cells. And the anti-pruritic effects were evaluated by Histamine, Acetylcholine (ACh), Acetylcholinesterase (AChE), Substance P production amount in Mast cell/9 (MC/9) and Pheochromocytoma 12 (PC12) cells. The anti-microbial effect was measured by inhibition zone diameter on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. Results: As a result of measuring anti-inflammatory efficacy, $IL-1{\beta}$, IL-2, IL-6, $TNF-{\alpha}$, $PGE_2$, and $LTB_4$ production amounts were significantly reduced in the EST, SCT, WDT extraction groups compared with the control group, and significantly decreased the amount of $NF-{\kappa}B$, iNOS, and COX-2 gene expression and the amount of Phospho-Inhibitor kappa B alpha ($p-I{\kappa}B-{\alpha}$)/Inhibitor kappa B alpha ($I{\kappa}B-{\alpha}$) and $NF-{\kappa}B$ p65 protein expression. In addition, As a result of measuring the anti-pruritic effect, the amounts of histamine, ACh and Substance P were significantly decreased, and AChE production was slightly decreased, but it's significance did not appear. Finally the anti-microbial effects of EST, SCT, WDT extraction groups against Pseudomonas aeruginosa, Candida albicans and Aspergillus niger was inhibited, however the growth of Escherichia coli and Staphylococcus aureus was not inhibited. Conclusions: These data suggest that EST, SCT, WDT can be used to treat patients with leukorrhea.

• Journal of Life Science
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• v.22 no.5
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• pp.657-664
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• 2012

The aim of this study is to screen a therapeutic agent with a cognitive function. The inhibitory effect of $Curcuma$ $longa$ hot water extract (CLWE) on the angiotension-converting enzyme and acetylcholinesterase derived from rabbit lungs and neural cells (PC12), as well as its antioxidant effect, was investigated in this study. Thus, for the first time, the direct scavenging effect of CLWE on DPPH radicals, superoxide anions, hydroxyl radicals, lipid peroxidation, reducing power, and the protective effect of DNA oxidation related to oxidative stress was evaluated in vitro. In addition, it was observed that CLWE especially exhibited a scavenging effect on reducing power and superoxide anions in this study. CLWE showed a protective effect on DNA oxidation produced by hydroxyl radicals. Furthermore, CLWE inhibited the activity of angiotensin-converting enzymes above 0.25%. Additionally, the extract inhibited oxidative stress and inducible nitric oxide in neuronal cells. Therefore, these results demonstrated that CLWE has antioxidant activity and neuronal cell protective effects, suggesting that it may have great potential as a natural source for human health.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1672-1678
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• 2009

This study was carried out to investigate the total polyphenol, total flavonoid content, antioxidant activity, angiotensin I-converting enzyme (ACE) inhibitory activity, $\alpha$-glucosidase inhibitory activity, and antiproliferation activity of the citron seed. The citron seed were separated to hull and embryo, and extracted with n-hexane and 70% ethanol. Antioxidant activity of ethanol extract was higher than that of n-hexane extract. IC50 value for DPPH radical scavenging activity of ethanol extract of hull (CSE1) and embryo (CSE2) were 3.18 and 8.43 mg/mL, and those of total antioxidant activity were 19.96 and 11.28 mg AA eq/g, respectively. ACE inhibitory activity and $\alpha$-glucosidase inhibitory activity on CSE1 showed the highest values of 31.61 and 45.17%, respectively. Antiproliferation effects on the MCF7, HepG2, H460, HCT-116, and PC3 cell line showed the highest values of 14.09, 19.12, 12.29, 9.78, and 9.12% in extract concentration of 5 mg/mL, respectively. These results suggested that citron seed can be used for development of functional food material which have biological activities.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.279-286
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• 2008

The antioxidative activity of various enzymatic extracts from leaves of Perilla frutescens var. japonica was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. For this study, the leaves were enzymatically hydrolyzed by 8 carbohydrases (Dextrozyme, AMG, Promozyme, Maltogenase, Termamyl, Viscozyme, Celluclast, and BAN) and 9 proteases [Flavourzyme, Neutrase, Protamex, Alcalase, PP-trypsin (trypsin from porcine pancreas), papain, pepsin, $\alpha$-chymotrypsin, and BP-trypsin (trypsin from bovine pancreas)]. The DPPH radical scavenging activities of Promozyme and Alcalase extracts were the highest, and the $IC_{50}$ values were 77.25 and $109.66\;{\mu}g/mL$, respectively. All enzymatic extracts of the leaves scavenged hydroxyl radical, and the $IC_{50}$ values of Celluclast and pepsin extracts which were the highest activity were 243.34 and $241.86\;{\mu}g/mL$, respectively. The BAN and $\alpha$-chymotrypsin extracts showed the highest scavenging activities, and the $IC_{50}$ values were 21.13 and $33.23\;{\mu}g/mL$, respectively. The pepsin extracts from the leaves showed protective effect on $H_2O_2$-induced DNA damage. In addition, the pepsin extracts decreased cell death in PC-12 cells against $H_2O_2$-induced oxidative damage. The findings of the present study suggest that enzymatic extracts of the leaves possess antioxidative activity.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.20-27
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• 2010

Deer velvet antler was subjected to the extraction process using boiling water at three different temperatures (100, 110 and $120^{\circ}C$) and 70% ethanol solution. Functional components such as uronic acid, sulfated-glycosaminoglycans (sulfated-GAGs) and sialic acid in the extracts were analyzed, and their antioxidant activities were investigated using several in vitro models. Uronic acid and sulfated-GAGs content of each extract significantly decreased with increasing extraction temperature (p<0.05), while the residues obtained from the upper and middle part of the antler had a higher uronic acid content than the residues obtained from the base section. Sialic acid contents were highest in compounds extracted at $110^{\circ}C$, followed by 120 and $100^{\circ}C$. The 70% ethanol extracts also had a high levels of uronic acid content, but not for sulfated-GAGs and sialic acid. All extracts showed good antioxidant ability in a dose-dependant manner, with the $100^{\circ}C$ residue exhibiting the strongest activity compared to the 110 and $120^{\circ}C$ extracts. In relation to the hydroxyl radical scavenging activity and reduction power, the 70% ethanol extract exhibited the strongest activity. Furthermore, the velvet antler extracts inhibited apoptosis in hydrogen peroxide-induced PC-12 cells.