• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.109-115
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• 1997

This study was designed to investigate the effects of methionine(Met) on the activities of brain lipid peroxidation related enzymes in ethanol administrated rats of selenium(Se) deficiency. Male Sprague-Dawley rats were fed Se deficiency diets containing one of the three levels of Met (0, 3, 9g/kg diet) and ethanol(2.5g/kg of body weight) was administrated as 25v/v% ethanol treated groups orally. The rats sacrificed after 5 and 10 weeks of feeding periods. Alcohol dehydrogenase activity was increased in ethanol treated groups and was higher Met normal group than Met deficiency and excessive groups at 5 and 10 weeks dieting. Aldehyde dehydrogenase activity was decreased in ethanol treated groups and significantly decreased in Met deficiency group. Monoamine oxidase activity in brain was increased in ethanol treated groups and was predominently increased in Met deficiency groups. Superoxide dismutase and glutathione peroxidase activities were decreased in ethanol treated groups and tended to increase in proportion to level of dietary methionine. Glutathione S-transferase and catalase activities and lipid peroxide content were increased by ethanol administration and were higher Met deficiency group than normal and excessive groups.

• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.423-433
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• 2021

This study was performed to examine the neuroprotective effect of the ethyl acetate fraction from Eucommia ulmoides oliver leaf (EFEL) on PM_2.5-induced cytotoxicity. EFEL had higher total phenolic and flavonoid contents than the other fractions. In ABTS and DPPH radical scavenging activities, the IC₅₀ of EFEL was measured as 212.80 and 359.13 ㎍/mL, respectively. To investigate the neuroprotective effect of EFEL, MTT and DCF-DA assays were performed on HT22, MC-IXC, and BV-2 cells. EFEL effectively decreased PM_2.5-induced intercellular reactive oxygen species (ROS) content and inhibited PM_2.5-induced cell death. In the results of protein expression related to cellular cytotoxicity on microglial cells (BV-2), EFEL had an improvement effect on cell apoptosis and inflammatory pathways. Rutin and chlorogenic acid were identified as the main physiological compounds. Moreover, it was expected that EFEL, including rutin and chlorogenic acid, could be functional food substances with neuroprotective effects against PM_2.5-induced oxidative stress.

• Food Science and Preservation
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• v.31 no.3
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• pp.452-461
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• 2024

This study evaluated the in vitro antioxidant activities of ethanolic Polygonum multiflorum (P. multiflorum) extracts and their cytoprotective effects on H₂O₂-induced HT22 and SK-N-MC cells. Among ethanolic extracts of P. multiflorum, the 40% ethanolic extract of P. multiflorum exhibited high total phenolics and flavonoid contents, with 105.68 mg of GAE/g and 28.92 mg of RE/g, respectively. The 40% ethanolic extract of P. multiflorum showed a high 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and malondialdehyde (MDA) inhibitory effect. The 40% ethanolic extract of P. multiflorum also showed efficient inhibitory activity against α-glucosidase and acetylcholinesterase. Moreover, the 40% ethanolic extract of P. multiflorum reduced oxidative stress and increased cell viability in H₂O₂-induced HT22 and SK-N-MC cells as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zoliumbromide (MTT) and 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA) assay. High-performance liquid chromatography (HPLC) identified 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside (TSG) as the bioactive compound in the 40% ethanolic extract of P. multiflorum.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.257-261
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• 2013

Rat pheochromocytoma cells (PC12) and mice were utilized as in vitro and in vivo models to determine the neuroprotective effects of a 70% acetone extract of black soybean seed coat (BSSCE). BSSCE showed higher total phenolic contents than other extracts. Intracellular reactive oxygen species accumulation from $H_2O_2$ treatment of PC12 cells was significantly reduced when BSSCE was present in the media compared to PC12 cells treated with $H_2O_2$ only. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromide (MTT) reduction assay and lactate dehydrogenase assay also showed significantly increased protective effects in PC12 cells. In addition, BSSCE improved the in vivo cognitive ability against amyloid beta peptide-induced neuronal deficits.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.390-391
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• 2011

초전도전력기기 실계통 적용 시범사업이 정부지원으로 한국전력이 주관하고 제작업체가 참여하는 방법으로 이천변전소에서 진행되고 있다. 이천변전소는 무인변전소로 구내에는 전자제어 및 계전기 등 전기적 잡음에 민감한 설비의 설치가 증가하고 있다. 따라서 개폐장치의 스위칭 동작, 뇌격의 침입, 기존 GIS대신 친환경 고체 절연 개폐장치(SIS)의 사용으로 변전설비 보호를 위한 접지설계가 중요하며, 고체절연개폐장치(SIS)의 상도체와 외함사이에 유도결합에 의해 발생하는 이상전압 등 변전소 구내외에서 발생하는 써지의 접지망 유입에 의한 접지도체의 전위상승이나 유도전압에 대한 대책이 필요하고, 특히 초전도 전력기기의 안정적인 운영을 위한 기술적인 접지망 분석 및 설계가 요구되고 있다.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.283-286
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• 2001

본 논문은 전력 품질개선장치인 DVR(Dynamic Voltage Restorer)시스템의 제어알고리즘 개발에 관한 것이다. DVR은 배전전계통에 직렬변압기를 통해 설치되어 전원의 순간전압강하(Voltage sag)를 보상하는 장치이며 전력변환장치 직렬변압기 에너지저장장치, 충전장치, 보호장치등으로 구성된다. 지락사고, 비선형부하의 순간투입, 뇌서지등 여러 요인에 의해 3상전원에서 발생하는 다양한 형태의 전압sag 보상이 가능한 제어알고리즘 모델을 제시하고 컴퓨터시뮬레이션을 통해 기본성능을 확인한 후 소형 DVR을 제작해 시험하였으며 이시험결과를 실 용량 DVR시제품의 설계에 이용하였다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2011.11a
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• pp.76-77
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• 2011

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.6
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• pp.279-285
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• 2005

The lightning causes the damage of power system equipments as well as large power failure. Therefore, the insulation design should be established not only to decrease the damage of the facilities itself but also to increase the reliability of electric power system. This paper describes the useful way applying underbuilt ground wire and guy wire in transmission tower that safely protect the substation equipments. One or more shield wires under the phase conductor will not intercept lightning stroke, but they may improve reduce lightning voltages almost as effectively as if they were above the phase conductors. And the guy wires will mitigate the tower surge response. These would not only reduce backflashover possibility but also minimize crest and duration of surges entering the substation. EMTP is used to analyze the efficiency of the proposed methods.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.8
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• pp.454-460
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• 2004

The effects of surge arresters for protection of transmission systems against direct lightning strokes have already been reviewed using Electromagnetic Transients Program(EMTP). Distribution lines are spanned in much larger area than transmission lines, and therefore, are more susceptible to lightning strokes. We have modelled the 22.9kV underground distribution cable systems that have arresters and grounding wires. And this paper analyzes the overvoltages on underground distribution cable systems when direct lightning strokes strike on the overhead grounding wire using EMTP. Then we investigated that (1) the effects of lightning stroke according to underground distribution cable length (2) voltages at the riser pole and at the cable terminal according to installation of arrester. This study will provide insulation coordination methods for reasonable systems design in 22.9kV underground distribution cable systems.

• Korean Journal of Acupuncture
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• v.25 no.1
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• pp.155-164
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• 2008

목 적 : 본 연구의 목적은 양릉천 침 처치 시 C57BL/6 생쥐의 중뇌 흑질에 위치한 도파민성 신경세포 사멸 억제 효과를 조직화학 염색법을 이용하여 Tyrosine hydroxylase(TH)와 laminin의 발현으로 관찰하고자 한다. 실험방법 : 실험에 이용한 동물은 C57BL/6 생쥐로, 매일 25mg/kg의 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)를 5일간 주사하였고, 매일 MPTP 주사한 뒤 2시간 후에 양릉천에 침치료를 시행하였으며 MPTP 주사를 종료한 뒤 침치료는 7일동안 계속 시행하였다. 마지막 MPTP 주사 7일 후에 동물을 희생하여 뇌를 적출하고 고정하였다. 침효과를 확인하기 위해 Thyrosine hydroxylase(TH), laminin의 발현 변화 정도를 조직염색화학법으로 이용하여 확인하였다. 각 그룹간의 유의성 검증은 one-way ANOVA를 이용하였다. 결 과 : 도파민성 신경세포 선택적인 신경독소인 MPTP에 대한 양릉천 침처치에 의한 신경보호 효과를 도파민신경세포의 표지자인 TH 발현을 면역화학조직염색법으로 관찰하였다. 대조군에 비해 MPTP 처치 군의 신경세포 사멸이 유의적으로 감소하였고(P <0.05), MPTP + 침처치 군에서 증가되는 양상을 확인하였다 (P <0.05). 또한 도파민성 신경세포내에 존재하는 laminin의 발현정도 역시 대조군보다 MPTP 처치 군에서 유의적으로 감소하였고, MPTP + 침처치 군에서 증가되는 양상을 확인하였다 (P <0.05). 결 론 : MPTP에 의한 도파민성 신경세포 손상에 대한 양릉천 침처치의 신경보호 효과는 세포외 기질중의 하나인 laminin의 발현 정도를 조절하여 비롯되는 것으로 사료된다.