• Advances in Traditional Medicine
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• 제10권4호
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• pp.271-277
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• 2010

We tested to determine if Mori Cortex Radicis extract has antioxidant activities and its potential mechanism of action was explored. Anti-oxidative effects were tested by measuring free radical and nitric Oxide (NO) scavenging activity, and reducing power. Since iNOS and COX-2 are important enzymes responsible for the production of free radicals in the cell, Mori Cortex Radicis extract was tested as to whether it could inhibit iNOS and COX-2 expression in LPS stimulated Raw cells. 70% methanolic extract of Mori Cortex Radicis exerted significant DPPH free radical and NO scavenging activities. In addition, the Mori Cortex Radicis extract exerted dramatic reducing power with maximal activity observed at 1 mg/ml (11-fold over control). Production of iNOS induced by LPS was significantly inhibited by the Mori Cortex Radicis extract, suggesting it could inhibit NO production by suppressing iNOS expression. COX-2 induced by LPS was also significantly inhibited by the Mori Cortex Radicis extract. The extract contains well known antioxidant components including phenolics, flavonoids and anthocyanin at the concentration of 0.23 mg/g, 42.97 mg/g and 12.08 mg/g, respectively. These results suggest that 70% methanolic extract of Mori Cortex Radicis exerts significant anti-oxidant activity via inhibiting iNOS and COX-2 induction.

• Environmental Analysis Health and Toxicology
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• 제8권3_4호
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• pp.33-41
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• 1993

This study was designed to determine the hemolytic mechanism of antitumor agent tetraphosphine platinum (II) complex (RC-1), which was synthesized recently. Erythrocytes treated with RC-1 showed concentration and time dependent lipid peroxydation, methemoglobin synthesis and hemolysis. And also treatment of radical scavengers showed the inhibitory effect of hemolysis and the decrease of malondialdehyde levels in RC-1 treated erythrocytes. So, the mechanism of hemolysis was considered to be the generation of free radicals, methemoglobin synthesis and the lipid peroxidation of phospholipid which composed of erythrocyte membrane.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.321-321
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• 2006

Aromatic diacetylenes form stable oligomeric diradicals when irradiated with UV light or heated at temperatures above their melting points. In this paper, the formation of stable diradicals is discussed, and the mechanism of polymerization in the presence of peroxide in solution, is discussed. The diphenyldiacetylene undergoes polymerization through coupling of diradicals, and not by the successive addition of radical species.

• 대한화학회지
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• 제17권1호
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• pp.1-9
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• 1973

區區한 Diels-Alder 反應의 구조를 규명하기 위하여 Diels-Alder 反應 基 自體의 本質에 가장 가깝다고 생각한 새로운 擬似分子化合物이라는 遷移狀態의 模型을 假定하여 Mulliken의 分子化合物의 量子力學을 適用하였다. 이 擬似分子化合物은 이온성과 Radical성을 지닌 混成體이다. 이 混成體의 波動函數는 다음 식으로 표현된다. ${\psi}_{complex} = {\psi}(R,S) + {\rho}{\psi}(R^+,S^-)$ 여기 ${\rho}$는 擬似分子化合物의 極性程度를 나타내는 것이고 이 ${\rho}$가 Diene과 Dienpohile의 反應中心原子들의 自由原子價의 차 $({\Delta}F)$에 關係함을 밝혔다. 아울러 이 ${\Delta}F$量이 Brown氏의 Lp量 및 Dewar氏의 ${\Delta}E_{deloc}$量과 直線성이 있음을 알았다. Diels-Alder反應의 可能性與否를 24組의 反應組에 對하여 豫言하였다. 따라서 우리가 假定한 遷移狀態의 模型이 眞實에 가깝다고 볼 수 있으며 결국 Diels-Alder 反應은 同時附加로 융합된 ionic-Radical mechanism으로 反應이 進行한다고 볼 수 있다.

• 한국식품영양과학회지
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• 제31권1호
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• pp.109-116
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• 2002

본 연구는 김치와 노화 억제에 미치는 영향을 살펴보기 위하여 AIN-76 마우스 식이에 배추, 갓김치, 갓배추김치를 각동결건조 김치를 5%씩 첨가하여 만든 후 김치식이를 노화촉진쥐인 SAMP8에게 1년간 섭취시키면서 간의 노화관련 특성인 유리기 농도와 항산화효소계의 효소활성 변화를 살펴보았다. 노화촉진쥐 간의 총유리기, OH radical, $H_2O$$_2$그리고 TBARS 모두 가려에 따라 증가되었으며, 간에서 생성된 유리기 농도와 TBARS 농도는 대조군에 비해 김치섭취시 유의적으로 감소되었다(p<0.05). 그러나 생성된 유리기를 제거하기 위한 SOD 활성은 오히려 김치섭취군에서 유의적으로 증가되었으며(P<0.05), catalase와 GSH-px, GSH/GSSG의 비율도 김치섭취군에서 유의적으로 증가하였다(p<0.05). 따라서 김치섭취는 노화에 따라 발생되는 간의 유리기 및 TB-ARS 생성은 억제시키면서, 이를 제거하는 항산화계 효소는 활성화시켜 노화를 억제한 것으로 생각된다. 김치종류 중에서는 배추김치보다 배추갓김치와 갓김치가 유리기 생성 억제 및 항상화 효소 활성을 더욱 증진시킨 것으로 관찰되어 이는 첨가된 갓의 항산화물질 때문인 것으로 생각된다.

• 동의생리병리학회지
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• 제19권5호
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• pp.1349-1355
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• 2005

The steamed root of Rehmannia glutinosa has been used for treatment of inner ear diseases, such as tinnitus and hearing loss in traditional Oriental Medicine. In the present study, we investigated the effect of ethanol extract of steamed root R. glutinosa (SRG) on cisplatin cytotoxicity of HEI-OC1 auditory cells. In addition, to investigate the mechanism of SRG on cisplatin cytotoxicity, the effects of SRG on lipid peroxidation as well as scavenging activities against various free radicals were measured in cisplatin-treated cells. Treatment of SRG protected cells from cisplatin and reduced lipid peroxidation in a dose-dependent manner. Furthermore, SRG demonstrated significant scavenging activity against various free radicals, including superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that SRG protects cisplatin-induced damages of HEI-OC1 cells through inhibition of lipid peroxidation and augmenting scavenging activities against free radials.

• 동의생리병리학회지
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• 제21권2호
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• pp.462-467
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• 2007

The radix of Pueraria thunbergiana BENTHAM (Leguminosae) is traditionally prescribed to attenuate the clinical manifestations of inner ear dysfunction and various clinical situations including fever, gastrointestinal disorders, skin problems, migraine headaches, lowering cholesterol and treating chronic alcoholism in Oriental Medicine. In the present study, we examined the effect of ethanol extract of P. thunbergiana radix (EPR) on cisplatin-mediated HEI-OC1 auditory cell death. In addition, to investingate the protection mechanism of EPR on free radicals. Treatment of EPR protected cells from cisplatin and reduced lipid peroxidation in a dose-dependent manner. Furthermore, EPR demonstrated significant scavenging activity against various free radicals, including superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that EPR protects cisplatin-induced damages of HEI-OC1 cells through inhibition of lipid peroxidation and augmenting scavenging activities against free radials.

• 대한의생명과학회지
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• 제8권3호
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• pp.155-159
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• 2002

To evaluate the physiological significance of xanthine oxidase (XO) in rat skin, the activity of XO (type O) in skin was compared with that of small intestine or liver. Concomitantly, XO activities in some partial portions (scalp, leg, dorsal and ventral part) of skin were determined and then compared with each partial portion. XO activity of skin was lower than that of small intestine and rather higher than that of liver. Furthermore, the activity of XO in skin, after clipping of hairs and then in 5 days, was more increased than that of rat which was clipped before having been sacrificed. As for activities of free radical scavenging system (GPx, GST, SOD), skin is lower than liver and small intestine. Although it is hewn that the oxygen free radical generated by XO system lead to injurious effect on the cell, the XO activity of ventral part which is to be less exposed to xenobiotics and biological agents was the lowest among those of ventral, dorsal, leg and scalp parts in skin. In conclusion, it may be hypothesized that XO system in skin act on defence mechanism.

• 약학회지
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• 제45권3호
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• pp.258-268
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• 2001

Garlic has been known to be effective against the gastrointestinal diseases which can be induced by production of oxygen-derived free radical. It has been shown that bamboo salt is effective on the treatment and prevention of various gastrointestinal disorders. Bamboo salt is a processed salt invented by a Korean, ll-Hoon Kim. It has been reported that garlic and bamboo-salt are useful to the treatment of gastric disorders in Korea. To clarify the protective mechanism of the garlic-bamboo salt mixture, the gas-tropathy was induced in rats with alcohol-salicylate and the activities of the free radical scavenging enzymes were examined. In this study, we found that the garlic-bamboo salt mixture reduced the severity of hemorrhagic lesion in gastric mucosa in the rats. In addition, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) were significnatly increased and the total content of GSH was recovered. From those results, we concluded that the protective effect of the garlic-bamboo salt mixture on gastropathy in rats is its ability to recover the level of GSH and to increase the activities of the free radical scavenging enzymes (SOD, GPx, GR).

• Environmental Analysis Health and Toxicology
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• 제8권3_4호
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• pp.23-32
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• 1993

This study was designed to elucidate the mechanism of nephrotoxicity caused by antitumor agent tetraphosphine platinum (II) complex (RC-1), which was synthesized as a tetraphosphine Pt (II) derivatives recently. Rats treated with RC-1 (20mg/kg/day) showed the increase of BUN value and malondialdehyde contents in kidney homogenate, compared to the control and which means the lipid peroxidation was a main cause of nephrotoxicity. In order to investigate the cytotoxic mechanism of RC-1, we also tested and revealed the generation of oxygen free radicals derived from neutrophil stimulated by RC-1 and interaction of the oxygen free radicals with the erythrocyte membrane. From the above results, we suggest that nephrotoxicity of general platinum (II) antitumor compounds as well as RC-1 were inhibited by radical scavengers.