• 전기화학회지
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• 제3권3호
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• pp.131-135
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• 2000

[ $LiMn_2O_4$ ]박막전지의 충방전 사이클에 따른 용량 감소의 원인을 파악하기 위하여, $LiMn_2O_4/1M\;LiClO_4-PC/Li$전지를 구성하여 충방전 사이클에 따른 AC impedance분석을 수행하였다. 적절한 등가회로를 이용하여 비선형 최소자승 맞춤에서 얻은 값이 Impedance측정 결과와 잘 일치하였다. 충방전에 따른 정전용량은 초기의 급격한 감소를 보인 이후 완만한 감소를 보였다. 충방전 사이클이 초기 70-100사이클까지는 저항 성분 중 양극전해질 계면의 전하 전달저항 성분이 급격히 증가하다가 이후 안정된 값을 보임으로 초기 급격한 용량변화의 원인으로 파악되었다. 전하전달 저항이 안정된 이후에는 Warburg저항이 충방전에 따라 조금씩 증가하였으며, LiMn2O4박막의 화학확산 계수가 사이클에 따라 초기 $5.15\times10^{-11}cm^2/sec$에서 800사이클이 지난 후 $6.3\times10^{-12}cm^2/sec$로 점차 감소하는 것이 관찰되어 100사이클이 후의 용량감소의 지배적 원인으로 파악하였다. Warburg저항의 증가는 Jahn-Teller변형 또는 Mn용해에 의한 것으로 추정하였다.

• 한국식품저장유통학회지
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• 제18권3호
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• pp.358-365
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• 2011

본 연구에서는 시판 메밀차 열수 추출물의 항산화 효과 및 신경세포 보호효과를 조사하였다. 시판 메밀차 열수 추출물의 ABTS 라디칼 소거 활성, FRAP 및 MDA 생성 저해 실험결과 농도 의존적인 경향이 나타났으며 또한 높은 항산화 활성을 보여주었다. 과산화수소로 유발된 산화적 손상에 의한 ROS 축적량을 조사한 결과 $H_2O_2$ 단독 처리구보다 메밀차 열수 추출물 처리구에서 낮은 ROS 축적량을 나타내었다. MTT 및 LDH 분석을 통한 PC12 세포 중의 신경세포 보호효과를 측정한 결과 MTT 분석에서는 시판 메밀차 열수 추출물의 모든 농도에서 높은 세포 생존율을 나타냈고, LDH 분석에서는 추출물에 의한 농도 의존적인 세포질 효소 (LDH) 방출량 감소가 관찰되었다. 총 페놀성 화합물, rutin 및 quercitrin의 함량은 각각 9,608.10 mg/g, 13.42 및 0.90 mg/100 g이었다. 본 연구결과를 종합해 볼 때 rutin 및 quercitrin과 같은 다양한 페놀성 화합물을 함유한 시판 메밀차 추출물은 항산화 활성과 산화적 스트레스로 유발된 신경세포 보호효과를 나타내어 퇴행성 신경질환 등을 예방 할 수 있는 기능성 식품 소재로서의 활용 가치가 높을 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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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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• 제22권5호
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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.

• 동의신경정신과학회지
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• 제20권2호
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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

• 대한한방부인과학회지
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• 제32권3호
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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.

• 생명과학회지
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• 제22권5호
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• pp.657-664
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• 2012

본 연구의 목적은 인지기능을 가진 약효제를 발굴하는 것이다. 본 연구에서는 토끼의 간과 신경세포로부터 각각 유래한 angiotension converting enzyme과 acetylcholinesterase에 대한 강황 열수추출물(CLWE)의 억제효과 뿐만 아니라 항산화 효과가 조사되었다. 이리하여 먼저 산화적 스트레스와 연관이 있는 환원력과 DPPH radical, superoxide anion, hydroxyl radical, lipid peroxidation에 대한 CLEW의 소거능 및 DNA 산화에 대한 보호효과를 평가하였다. CLEW는 환원력 뿐만 아니라 본 연구에서 시험된 활성산소종 중에서 특히 superoxide anion의 소거능이 가장 우수한 것으로 나타났다. 더욱이 CLEW는 0.25% 이상의 농도에서 angiotensin converting enzyme 활성을 억제효과를 발휘하는 것으로 나타났다. 신경세포에서 CLEW는 또한 산화적 스트레스와 nitric oxide 유발을 억제하였다. 그러므로 이상의 결과는 CLEW의 항산화 효과와 신경세포 보호효과를 입증하여, 이것이 사람의 신경건강을 위한 천연생물소재로 잠재적인 가능성을 가지고 있을 것으로 시사한다.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1672-1678
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• 2009

유자씨 종피와 배유부분에 대한 n-hexane 및 ethanol 추출물에 대한 항산화활성, ACE 저해활성, $\alpha$-glucosidase 억제활성 및 항암활성을 살펴보았다. 항산화활성은 종피 nhexane 추출물(CSH1), 배유 n-hexane 추출물(CSH2), 종피 70% ethanol 추출물(CSE1) 및 배유 70% ethanol 추출물(CSE2) 가운데 CSE1이 가장 높은 활성을 나타내었으며, CSE1의 용매분획물 가운데 ethylacetate 층이 2 mg/mL의 농도에서 라디칼소거능이 73.81% 그리고 총항산화력이 56.64 mg AA eq/g으로 우수한 항산화활성을 나타내었다. 또한 ACE 저해활성과 $\alpha$-glucosidase 억제활성도 CSE1이 각각 31.63% 및 45.17%로 가장 높은 활성을 나타내었다. 각각의 추출물에 대한 유방암, 간암, 폐암, 대장암 및 전립선암 세포에 대한 증식억제효과는 모든 암세포에 대하여 5mg/mL의 농도에서 종피 ethanol 추출물(CSE1)이 가장 높은 암세포 증식억제효과를 보였다.

• Food Science and Biotechnology
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• 제17권2호
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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.

• 한국축산식품학회지
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• 제30권1호
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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.