• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.100-103
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• 2000

In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidase (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized the enzyme electrode by electropolymerization added some organic solvent. A formative seeds of film growth is delayed by adding ethanol. The delay is induced by radical transfer between ethanol and pyrrole monomer. The radical transfer shares the contribution of dopant between electrolyte anion and GOx polyanion. This may lead to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased. We established qualitatively that amount of immobilization can be improved by adding a little ethanol in the synthetic solution. It is due to radical transfer reaction. The radical transfer shares the contribution of dopant between small and fast electrolyte anion and big and slow GOx polyanion.

• Korean Journal of Acupuncture
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• 제28권2호
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• pp.23-36
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• 2011

목적 : 이 연구는 관절 및 심혈관계 질환 치료에 사용되는 송절(松節)(Pinus densiflora Gnarl)을 약침용 시료로 조제하여 본 약물의 항산화 효능을 규명하고자 하였으며 이를 다양한 시스템에서 검토하였다. 방법 : $FeCl_2$-ascorbic acid system에서 흰쥐 간조직의 지질과산화 반응을 관찰하였고, Fenton reaction system에서 자유기에 의한 plasmid DNA 분절을 유도하였다. 또한 deoxyribose assay를 통해 hydroxyl radical 소거능을 관찰하였고, NBT reduction assay로 superoxide radical 소거능을 검토하였다. 또한 human low-density lipoprotein(LDL)의 산화를 유도하기 위해 $CuSO_4$와 AAPH를 사용하였으며 relative electrophoretic mobility (REM) assay로 LDL 산화 억제 효능을 대조 항산화물질과 비교 검토하였다. 결과 : 송절 약침액은 자유기에 의한 간조직의 지질과산화(p < 0.01)및 DNA 분절을 현저하게 억제하였으며, hydroxyl radical, superoxide radical (p < 0.01), nitric oxide 및 peroxynitrite를 강하게 소거하였다. 또한 $CuSO_4$ ($IC_{50}=9.2{\pm}0.2\;{\mu}g/ml$)와 AAPH ($IC_{50}=34.8{\pm}5.1\;{\mu}g/ml$)에 의해 유도된 human LDL의 산화를 억제하였고, REM assay에서도 산화 억제 효능을 재확인할 수 있었다. 결론 : 송절 약침액은 활성산소종 및 활성질소종를 소거하였고, 지질과산화를 억제하였으며, 특히 human LDL의 산화적 손상을 방어하였다. 이에 본 약물은 자유기에 의한 심혈관의 산화적 손상을 효과적으로 보호할 것으로 판단된다.

• Journal of Photoscience
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• 제9권2호
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• pp.138-141
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• 2002

A photo-labile compound which is bioinactive but, upon irradiation with light, yields bioactive species is called as "caged compound". Photolysis of caged compounds generating bioactive species, has become a general method to produce a desired amounts of bioactive species in the specific time interval at the desired place or area of the target biological systems. For this purpose, we designed and synthesized caged hydroxyl radical., "Photo-Fenton Reagent" NP-IIl. NP-IIl has a strong absorption maximum at 377 nm and yields hydroxyl radicals upon UV light irradiation. The antioxidant activity of the ${\alpha}$ -lipoic acid and other naturally occurring compounds has been examined by using NP-IIl as a molecular probe. For example, upon photoirradiation of NP-lII with BSA or apolipoprotein of human low density (LDL), the significant oxidative modifications were observed in both cases. The oxidation was completely suppressed in the presence of ${\alpha}$-lipoic acid, which clearly demonstrates the strong hydroxyl radical scavenging activity of ${\alpha}$-lipoic acid. Other applications of NP-lII will also be described

• Biomolecules & Therapeutics
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• 제12권3호
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• pp.133-137
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• 2004

Present review is built on base of research work on Ganoderma lucidum in our laboratory. A great deal of experimental evidence has suggested that the pharmacological activities of Ganoderma lucidum (Lingzhi) are related to anti-oxidative and free radical scavenging activity. The anti-oxidative and free radical scavenging effects of polysaccharides and triterpenoids isolated from Ganoderma lucidum in different oxidative injury models including tert-butylhydroperoxide (tBOOH)- damaged mice peritoneal macrophages, alloxan-induced diabetes, experimental liver injury models induced by carbon tetrachloride (CCl4), D-galactosamine (DGal) and Bacillus Calmette-Guerin (BCG) plus lipopolysaccharides (LPS) were investigated. It is also demonstrated that Lugu lingzhi, one of Ganoderma product, significantly inhibited LDL oxidation mediated by endothelial cells and decreased monocyte adhesion to endothelial cell (EC) induced by Oxidative low-density lipoprotein (ox-LDL) and advanced glycation endproducts (AGE). Lugulingzhi-treated serum could markedly inhibit the expression of intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-l) induced by ox-LDL and AGE.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2004년도 Annual Meeting of KSAP : New Drug Development from Natural Products
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• pp.61-77
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• 2004

Present review is built on base of research work on Ganoderma lucidum in our laboratory. A great deal of experimental evidence has suggested that the pharmacological activities of Ganoderma lucidum(Lingzhi) are related to anti-oxidative and free radical scavenging activity. The anti-oxidative and free radical scavenging effects of polysaccharides and triterpenoids isolated from Ganoderma lucidum in different oxidative injury models including tert-butylhydroperoxide (tBOOH)- damaged mice peritoneal macrophages, alloxan-induced diabetes, experimental liver injury models induced by carbon tetrachloride (CC14), D-galactosamine (DGal) and Bacillus Calmette-Guerin(BCG) plus lipopolysaccharides(LPS) were investigated. It is also demonstrated that Lugu lingzhi, one of Ganoderma product, significantly inhibited LDL oxidation mediated by endothelial cells and decreased monocyte adhesion to endothelial cell (EC) induced by Oxidative low-density lipoprotein (ox-LDL) and advanced glycation endproducts(AGE). Lugulingzhi-treated serum could markedly inhibit the expression of intercellular cell adhesion molecule-l (ICAM-1) and vascular cell adhesion molecule-l (VCAM-1) induced by ox-LDL and AGE.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.473-476
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• 2004

This study has investigated radiation degradation of low density polyethylene(LDPE). Samples were irradiated using a $Co^{60}\;\gamma-ray$ and ray up to 800 kGy at a dose rate of 5 kGy/hr in the presence of air atmosphere at room temperature. After irradiation, free radical measurement of LDPE has established by electron spin resonance(ESR). Then, each sample was stored for 2 weeks. ESR measurement showed that free radical concentration(FRC) was increased with radiation dose and changed from alkyl, allyl radical to peroxy radical with time.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.935-938
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• 1999

Reactivity and reaction mechanism for the reactions of 1,1'-(azodicarbonyl) dipiperidine with triphenylphosphines are investigated using kinetic method. The cation radical, Ph3P and the anion radical, -N-N - are produced during the course of the reaction. The cation radical is formed by the transfer of an electron from phosphorus to the nitrogen atom. The anion radical is formed by the addition of the one electron to the azo rad-ical. The rate constants are decreased by electron withdrawing groups while they are increased by electron donating groups present in triphenylphosphine. The electron density increases on nitrogen, while positive charge is developed on phosphorus in the transition state.

• 한국진공학회지
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• 제20권6호
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• pp.422-429
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• 2011

식각공정에 주로 사용되는 $Cl_2$/Ar, $CF_4$, $CF_4/O_2$, $CF_4/H_2$, $C_2F_6$, $C_4F_8$, 그리고 $SF_6$ 가스 방전에서 이온, 중성종 및 활성종 밀도의 전자밀도와 온도에 대한 의존성을 수치해석적으로 분석하였다. 이온, 중성종 및 활성종 밀도에 대한 공간평균 유체방정식을 정상상태로 가정하여 상대적으로 측정이 용이한 전자밀도와 온도에 대한 식으로 표현하였고, 이 식을 수치해석적인 방법으로 풀었다. 계산에 사용된 반응계수들은 여러 문헌에서 수집되거나 산란단면적으로부터 계산되었고, 같은 반응에 대해 다른 값을 보일 경우, 계산 결과를 실험 결과와 비교하여 높은 일치도를 보이는 값이 선택되었다.

• Natural Product Sciences
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• 제14권2호
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• pp.107-112
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• 2008

The six phenolic compounds isolated from the root of Dipsacus asper, 3,4-di-O-caffeoylquinic acid (1), methyl 3,4-di-O-caffeoyl quinate (2), 3,5-di-O-caffeoylquinic acid (3), methyl 3,5-di-O-caffeoyl quinate (4), 4-5-di-O-caffeoylquinic acid (5), methyl 4,5-di-O-caffeoyl quinate (6) were continuously evaluated for their antioxidant activity using superoxide radical scavenging and AAPH-mediated (LDL) oxidation assay. The results demonstrated that compounds 1 - 6 had remarkable antioxidant activities with the $IC_50$ values ranging from 12.0 to $2.8{\mu}M$ in superoxide radical scavenging. They also inhibited AAPH-mediated low-density lipoprotein LDL oxidation by the generation of thiobarbituric acid reactive substances (TBARS) with $IC_50$ ranging from 6.7 to $8.7{\mu}M$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.209.2-209.2
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• 2016

Up to now, Plasma applications are thought as a leading technology in industrial, chemical and even medical and biological field. Especially, Due to direct discharge in liquid with reaction in ambient solution, plasma in liquid is useful plasma technology. Such as electro-surgery, water purification, radical generation for synthesis. For using those plasma applications efficiently, plasma characteristics should be understood in advance. But discharge in liquid is not much well-known about its characteristics. And plasma discharge in solution is difficult to generate and analysis due to electrolysis, vaporization and radical generation. So, We make stable plasma discharge in solution(saline 0.9%) without input gas. We also analyze new type of plasma source in thermal and electrochemical view. And we check characteristics of plasma in liquid. For example, plasma density and radical density(OH) with optical emission, thermal energy with thermometer, electrical energy with oscilloscope and so on. And we try to explain the bubble and plasma formation with circuit analysis.