• 에너지공학
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• 제17권1호
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• pp.8-14
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• 2008

폐 농업용 비닐을 이용한 연료유 생산 공정을 위한 저밀도폴리에틸렌(LDPE)과 에틸렌비닐아세테이트(EVA) 수지에 대한 열분해 반응 실험을 하였다. 질소 분위기에서 상온에서 $650^{\circ}C$까지의 비등온 조건에서의 열분석기(열중량분석기, 시차주사열량계)와 $420^{\circ}C$의 배치형 반응기에서 무촉매반응과 소성 백운석,소성 석회석, 소성 굴껍질 등의 칼슘계 촉매를 사용한 열분해가 행하여졌다. TGA 실험에서 가열속도에 따라서 LDPE의 열분해 개시온도는 $330{\sim}360^{\circ}C$로 변화되었다. EVA 수지는 $300{\sim}400^{\circ}C$의 1차분해영역과 $425{\sim}525^{\circ}C$의 2차분해 영역에서 열분해 되었다. LDPE 수지에 10% 칼슘계 촉매 첨가 시 소성백운석 첨가가 반응 속도를 증가시켰다. EVA 수지 열분해 실험에서는 칼슘계 촉매 첨가가 열분해 반응을 다소 지연시켰다. DSC 실험에서 칼슘계 촉매는 LDPE 수지 원료의 융해개시온도는 다소 낮추었지만 융해열에 대하여는 영향이 없었다. 소성백운석 첨가 시 열분해열을 20% 정도 감소시켰다. 회분식 반응기에서 소성백운석과 소성 석회석 첨가 시 연료유 생성 수율을 높였으나, 생성 연료유 내의 탄소 수 분포에는 큰 영향이 없었다.

• 한국식품저장유통학회지
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• 제19권4호
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• pp.604-610
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• 2012

블루베리 잎의 무기질은 칼슘과 칼륨의 순으로 많았으며, 유리당은 glucose가 대부분을 차지하였다. 아미노산은 glutamic acid, aspartic acid, leucine의 순으로 많이 함유되어 있었으며, 지방산 함량은 eicosenoic acid, palmitic acid순으로 높았다. vitamin C와 total flavonoid 함량은 각각 $112.64{\pm}0.02$ mg%, $13.09{\pm}0.01$ mg%이었다. 블루베리 잎 80% 에탄올 추출물을 이용한 분획물의 total phenolics 함량은 에틸아세테이트 분획물이 50.51 mg of GAE/g로 제일 높았으며, 블루베리 잎 에틸아세테이트 분획물의 ABTS 라디칼 소거활성 및 FRAP assay는 농도 의존적으로 항산화 활성이 증가하는 경향을 보였다. 본 연구 결과를 종합해볼 때, 생리활성 소재로서의 phenolics를 함유한 블루베리 잎은 양질의 영양학적 성분 구성 및 in vitro 항산화 효과를 기초로 한 고부가가치 건강지향 식품 소재로서의 활용가치가 높다고 판단된다.

• The Korean Journal of Physiology and Pharmacology
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• 제8권6호
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• pp.319-327
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• 2004

This study was aimed at evaluating the effect of defibrotide on the development of the surgically induced reflux esophagitis, on gastric secretion, lipid peroxidation, polymorphonuclear leukocytes (PMNs) accumulation, polymorphonuclear leukocytes adherence, superoxide anion and hydrogen peroxide production in PMNs, scavenge of hydroxyl radical and hydrogen peroxide, cytokine (interleukin-1 ${\beta}$, tumor necrosis $factor-{\alpha}$) production in blood, and intracelluar calcium mobilization in PMNs. Defibrotide did not inhibit the gastric secretion and not change the gastric pH. Treatment of esophagitis rats with defibrotide inhibited lipid peroxidation, and myeloperoxidase (MPO) in the esophagus in comparison with untreated rats. Defibrotide significantly decreased the PMN adherence to superior mesenteric artery endothelium in a dose-dependent manner, Superoxide anion and hydrogen peroxide production in $1{\mu}M$ formylmethionylleucylphenylalanine (fMLP)- or $0.1{\mu}g/ml$ N-phorbol 12-myristate 13-acetate (PMA)-activated PMNs was inhibited by defibrotide in a dose-dependent fashion. Defibrotide effectively scavenged the hydrogen peroxide but did not scavenge the hydroxyl radical. Treatment of esophagitis rats with defibrotide inhibited interleukin-1 ${\beta}$ production in the blood in comparison with untreated rats, but tumor necrosis $factor-{\alpha}$ production was not affected by defibrotide. The fMLP-induced elevation of intracellular calcium in PMNs was inhibited by defibrotide. The results of this study suggest that defibrotide may have partly beneficial protective effects against reflux esophagitis by the inhibition lipid peroxidation, PMNs accumulation, PMNs adherence to endothelium, reactive oxygen species production in PMNs, inflammatory cytokine production(i.e. interleukin-1 ${\beta}$), and intracellular calcium mobilization in PMNs in rats.

• Journal of Evidence-Based Herbal Medicine
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• 제1권1호
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• pp.13-18
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• 2008

Polygoni cuspidati Rhizoma (PCRH) has been used in treatment of menoxenia, skin burn, gallstone, hepatitis, hyperlipidaemia, favus athlete's foot, supperative dermatitis and inflammation. However, its effect in experimental models remains unknown. In this present study, the effect of PCRH for stability on mast cell was analyzed. Two g/kg PCRH inhibited the compound 48/80-induced anaphylaxis by 75%. In addition, PCRH inhibited the tumor necrosis factor-$\alpha$ and interleukin-8 secretion as compared with the phorbol 12-myristate 13-acetate plus calcium ionophore A23187 stimulated human mast cell line, HMC-1 cells. These results suggested PCRH may inhibit mast cell-mediated anaphylactic reaction.

• The Korean Journal of Physiology and Pharmacology
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• 제8권2호
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• pp.111-115
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• 2004

Roundabout (Robo) is the transmembrane receptor for slit, the neuronal guidance molecule. In this study, the tyrosine phosphorylation of Robo was observed in Robo-transfected human embryonic kidney cells and developing rat brains, and found to be increased by the treatment with protein kinase A activator, forskolin. In contrast, protein kinase C activation by phorbol-12-myristate-13-acetate decreased the phosphorylation of Robo. Intracellular calcium was required for the tyrosine phosphorylation. Furthermore, the transfection of an Eph receptor tyrosine kinase dramatically enhanced the tyrosine phosphorylation. These findings indicate that the tyrosine phosphorylation of Robo is regulated by multiple mechanisms, and that Eph receptor kinases may play a role in the regulation of tyrosine phosphorylation of Robo in the rat brain.

• Natural Product Sciences
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• 제15권3호
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• pp.139-143
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• 2009

The anaphylactic allergic reaction is involved in many allergic diseases such as asthma and allergic rhinitis. In this report, I investigated the effect of ripe fruits of Rubus coreanus Miq. (Rosaceae) (RFRC) on the anaphylactic allergic reaction and studied its possible mechanisms of action. RFRC inhibited compound 48/80-induced systemic anaphylactic reaction in mice. RFRC dose-dependently decreased the IgE-mediated passive cutaneous anaphylaxis. In addition, RFRC decreased the gene expression and production of tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin (IL)-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated human mast cells. These findings provide evidence that RFRC could be a candidate as an anti-allergic agent.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.54.1-54.1
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• 2011

Porous hydroxyapatite has been widely used as clinical implanted material. However, it has poor mechanical properties. To increase the strength as well as the biocompatibility of the porous HAp based artificial bone, it was fabricated by multi-extrusion process. Hydroxyapatite and graphite powders were mixed separately with ethylene vinely acetate and steric acid by shear mixing process. Hydroxyapatite composites containing porous microstructure were fabricated by arranging it in the die and subject it to extrusion process. Burn-out and sintering processes were performed to remove the binder and graphite as well as increase the density. The external and internal diameter of cylindrical hollow core were approximately 10.4 mm and 4.2 mm, respectively. The size of pore channel designed to increase bone growth (osteconduction) was around 150 ${\mu}m$ in diameter. X-ray diffraction analysis and SEM observation were performed to identity the crystal structure and the detailed microstructure, respectively.

• 대한한방소아과학회지
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• 제26권2호
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• pp.13-24
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• 2012

Objectives NJ is being used to treat inflammatory diseases in Korea. In this study, we attempted to evaluate the effects of NJ on atopic dermatitis (AD)-like lesions and mast cell-mediated allergy inflammation in vivo and in vitro. Methods and Results We investigated to ascertain the pharmacological effects of NJ on 2,4-dinitrofluorobenzene (DNFB)-induced allergic reactions under in vivo conditions. Additionally, to find possible explanations for the anti-inflammatory mechanisms of NJ, we evaluated the regulatory effects of NJ on the level of inflammatory mediators in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated human mast cells (HMC-1). Conclusions NJ inhibited the production of the inflammatory cytokines (IgE, IL-6, IL-8 and TNF-${\alpha}$) significantly in vivo and in vitro.

• Natural Product Sciences
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• 제10권1호
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• pp.24-28
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• 2004

The effects of aqueous extract of Artemisia iwayomogi (Compositae) (AIAE) on the mast cell-dependent allergic and inflammatory reactions were investigated. AIAE (0.05 to 1 g/kg) dose-dependently inhibited systemic allergic reaction induced by compound 48/80 in mice. AIAE (0.1 and 1 g/kg) also significantly inhibited local allergic reaction activated by anti-DNP IgE. AIAE (0.001 to 1 mg/ml) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80. Moreover, AIAE inhibited the secretion of interleukin (IL)-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated human mast cell line (HMC-1) cells. These results provide evidence that AIAE may be beneficial in the treatment of allergic diseases.

• 생약학회지
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• 제43권2호
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• pp.163-166
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• 2012

In the present study, we investigated the effect of the water extract of Perilla frutescens var. acuta (Labiatae; WEPF) on the mast cell-mediated allergic reactions. WEPF was anally administered to mice for high and fast absorption. WEPF inhibited compound 48/80-induced systemic allergic reaction. WEPF attenuated immunoglobulin E (IgE)-mediated local allergic reaction. In addition, WEPF decreased the gene expression of pro-inflammatory cytokines in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated HMC-1 cells. These results indicate that WEPF inhibits mast cell-mediated allergic reactions in vivo and in vitro.