• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1724-1726
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• 2001

This paper deals with the characteristics of the potential rises of down-conductor due to lightning surge currents. Direct lightning strikes can cause high impulse currents to the lightning protection system(LPS) of a building. These high impulse currents have the front time as short as 1[${\mu}s$]. In this case, the induced voltages caused in a closed circuit inside the building can be very high and cause damage or submit people to electric hazard. So, the LPS has to be designed to ensure safety condition to person and acceptable levels of induced voltages to the electrical and electronic equipments. The results of the potential rises related to the bonding conditions between the grounding conductor and metal raceway and the type of down-conductors are introduced.

• 대한한방소아과학회지
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• 제23권3호
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• pp.241-262
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• 2009

Objectives This study is designed to investigate the effects of Jujadokseo-hwan on the brain ability and inducing oxidative stresses. Methods We measured the changes of regional cerebral blood flow and mean arterial blood pressure. Then we analyzed histological examination, immunohistochemistric response and anti-oxidant activity of Jujadokseo-hwan. Results 1. Treatment of Jujadokseo-hwan significantly increased regional cerebral blood flow but decreased mean arterial blood pressure. 2. Treatment of Jujadokseo-hwan-induced increase of regional cerebral blood flow was significantly inhibited by pretreatment with indomethacin (1 mg/kg, i.p.), an inhibitor of cyclooxygenase. 3. In histological examination through TTC stain, group I was no change, but group II showed that discolored in the most cortical part. Group III showed that decreased discolor in the cortical part. 4. In immunohistochemistric response of BDNF, group II showed that lower response effect. Group III showed that increase response effect. 5. Treatment of Jujadokseo-hwan increased proliferation rates of Glial cell effectively 6. Treatment of Jujadokseo-hwan accelerated proliferation rates of C6 cells in vitro. In addition, protective effects on cell death induced by paraquat, rotenone and hydrogen peroxide. In addition, activity of SOD were increased by treatment with Jujadokseo-hwan. Conclusions In conclusion, Jujadokseo-hwan can improve of the brain ability, learning ability, memory ability and induce ischemic brain injuries.

• 생약학회지
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• 제42권1호
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• pp.22-26
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• 2011

Korean traditional prescription, Oyaksungisan was usually used to treat rheumatoid arthritis, paralysis. In this study, we compared the contents of five major components, ephedrine HCl, ferulic acid, hesperidin, 6-gingerol, glycyrrhizin and various unknown compounds in Ohyaksungisan (OY) with fermented Ohyaksungisan (FOY) by established HPLC-DAD method. The neuroprotective activity against glutamate-induced cytotoxicity in HT22 cell of OY and FOY was investigated by MTT assay. And anti-oxidative activity of OY and FOY was measured by DPPH radical, hydrogen peroxide and hydroxyl radical scavenging activity. After fermentation, contents of five major components and some unknown compounds (1), (2), (3) and (4) were increased in FOY. Also, FOY showed more potent neuroprotective activity. Furthermore, anti-oxidative activity of FOY was increased. In conclusion, the fermentation of OY could change contents various compounds and improved its neuroprotective activity.

• 생약학회지
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• 제45권2호
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• pp.161-167
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• 2014

Ganoderma lucidum L. (GL) is a traditional oriental medicine that has been widely used as anti-inflammatory, antitumor and anti-oxidant in Korea and other Asian countries. In this study, we investigated the ethanol extract of GL has neuroprotective effects in murine hippocampal HT22 cells. GL ethanol extract has the potent neuroprotective effects on glutamate-intoxicated cells by inducing the expression of heme oxygenase (HO)-1 in HT22 cells. GL ethanol extract increased JNK phosphorylation. Obviously, When we treated the GL extract with c-Jun N-terminal kinase (JNK) inhibitor (SP600125), HO-1 expression was reduced. Moreover, we found that GL treatment caused the nuclear accumulation of Nrf2. In conclusion, the ethanol extract of GL significantly protects glutamate-induced oxidative damage by induction of HO-1 via Nrf2, JNK pathway in mouse hippocampal HT22. These results suggest that GL ethanol extract would be a good source for taking active compounds and may be a potential pharmaceutical products for brain disorder induced by neuronal damage and oxidative stress.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1754-1756
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• 2002

This paper deals with an effective installation method of lightning protective devices for information and communication facilities. Due to the potential difference between grounding of the AC power lines and communication lines, the equipments connected to the communication lines are easily damaged by lightning surges. So we have examined the behaviors of surge protective devices against lightning surges from the AC power lines and signal lines, and the coordination effects of SPD installation method were investigated. As a result, it was confirmed that the bypass arrester method and common grounding method were very effected.

• 생약학회지
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• 제40권1호
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• pp.41-45
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• 2009

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzhemier's disease. Neuropathologically, PD is characterized by the selective loss of dopaminergic neurons. The neuronal toxicity of cytosolic excess dopamine (DA) has been described in many studies using several cell lines. In dopaminergic neurons, cytosolic excess DA is easily oxidized via monoamine oxidase (MAO)-B, tyrosinase or by auto-oxidation to produce neurotoxic metabolites such as DA quinone. So, in the present study, we induced cell death by treatment of DA ($600{\mu}M$) in human neuroblastoma SH-SY5Y cell which was treated samples before 24 hr, and cell viability was measured by fluorescence activated cell sorter (FACs) analysis. Of those tested, the extracts of Poria cocos (赤茯笭)(whole), Gastrodia elata (rhizomes), Eucommia ulmoides (炒)(barks), Syneilesis palmata (whole), Acorus gramineus (rhizomes), Ligustrum japonicum (leaves) showed neuroprotective effects in dose dependent manner.

• 대한한의학회지
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• 제23권1호
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• pp.1-10
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• 2002

Objectives: Uncariae Ramulus Et Uncus extract is clinically used in Korea to treat ischemic cerebral damage. The present study was undertaken to study the neuroprotective effect of Uncariae Ramulus Et Uncus extract in middle cerebral artery occlusion (MCAO) rats. Methods: Changes of extracellular levels of dopamine, DOPAC, HVA. and HIAA in striatum were collected at 20 minutes interval by in vivo microdialysis and then analyzed by HPLC (high performance liquid chromatography) in rats subjected to permanent focal cerebral ischemia induced by 2 hours of MCAO. Uncariae Ramulus Et Uncus extract was orally administrated before MCAO. Different animals were used for measurement of cerebral infarction volume induced by 24 hours of MCAO with TIC staining and image analysis. Results: Extracellular levels of dopamine decreased after treatment with Uncariae Ramulus Et Uncus extract, while extracellular levels of DOPAC and HVA significantly increased. Cerebral infarction volume also significantly decreased after treatment with Uncariae Ramulus Et Uncus extract. Conclusions: These results provided evidence that Uncariae Ramulus Et Uncus extract can produce a neuroprotective effect on cerebral ischemia by regulating extracellular excitatory neurotransmitters.

• 생약학회지
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• 제41권3호
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• pp.190-195
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• 2010

Glutamate-induced oxidative injury contributes to neuronal degeneration in many central nervous system (CNS) diseases, such as Parkinson's disease, Alzheimer's disease, epilepsy and ischemia. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a role in the pathogenesis of these diseases. NNMBS098, a composition comprising the water insoluble of the 70% EtOH extract of Zingiberis Rhizoma, showed the potent neuroprotective effects on glutamateinduced neurotoxicity by induced the expression of heme oxygenase (HO)-1 and increased HO activity in the mouse hippocampal HT22 cells. Furthermore, NNMBS098 caused the nuclear accumulation of nuclear factor E2-related factor 2 (Nrf2) in mouse hippocampal HT22 cells. In addition, we found that treatment with c-Jun N-terminal kinase (JNK) inhibitor (SP600125) reduced NNMBS098-induced HO-1 expression and NNMBS098 also increased JNK phosphorylation. Therefore, these results suggest that NNMBS098 increases cellular resistance to glutamate-induced oxidative injury in mouse hippocampal HT22 cells, presumably through JNK pathway-Nrf2-dependent HO-1 expression.

• 생약학회지
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• 제45권3호
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• pp.214-219
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• 2014

Artemisia apiacea is a traditional herbal medicine using treatment of eczema and jaundice in Eastern Asia including China, Korea, and Japan. In this study, the three phytosterol constituents were isolated and identified from the hexane fraction of 80% aqueous methanol extract of A. apiacea. Compounds were isolated using open column chromatography (silica gel). Their chemical structures were also established using $^1H$-NMR and $^{13}C$-NMR. Moreover, neuroprotective activity of each compound against glutamate-induced neurotoxicity in hippocampal HT-22 cell line was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, Inhibition of reactive oxygen species (ROS) and calcium ion ($Ca^{2+}$) accumulation were measured for elucidation of neuroprotective mechanism of isolated compounds. They showed that stigmasterol had neuroprotective activity against the glutamate-induced toxicity by inhibition of ROS and $Ca^{2+}$ production. In conclusion, isolated compound of A. apiacea might be useful for therapeutic agent against neurodegenerative diseases.

• 생약학회지
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• 제31권4호
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• pp.373-382
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• 2000

This study was performed to investigate the antithrombotic activity and protective effect of hexane fraction of Kamihyulbuchukeotang (KHCTH) on brain injury by KCN and MCA occlusion a prescription of HCT added with Lumbricus and Notoginseng Radix. Experiemental parameters are brain ischemia by MCA occlusion assay, KCN-induced brain injury, pulmonary thrombosis and platelet aggregation assay. The results were summarized as follows; 1. KHCTH extracts significantly inhibited the duration of KCN-induced coma (67%) and mortality (80%). 2. KHCTH extracts significantly suppressed brain ischemic area and edema following MCA occlusion and protected neuron cells as compared with control data. 3. KHCTH extracts inhibited pulmonary thrombosis induced by collagen and epinephrine. 4. KHCTH extracts inhibited platelet aggregation induced by collagen, ADP as agonist up to 76.9% and 32.3% respectivey at 1 mg/ml more effective than water extract of KHCT These data suggested that KHCTH could be applied as the protector of brain ischemia and injury and antithrombotic agent.