• 대한화장품학회지
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• 제22권2호
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• pp.201-210
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• 1996

Predictive tests for the identification of contact sensitizing chemicals have been developed. We measured the sensitization potential with three predictive tests, the in vitro and the in vivo Local Lymph Node Assay(LLNA), ELISA to detect interferon-gamma(IFN-${\gamma}$) from supernatant and flow cytometry to detect change of cell surface proteins, using draining lymph nodes of mice. BALB/c mice were exposed to various chemicals or vehicles on the ears daily for 3 consecutive days in all experiments. With some exceptions of propyl paraben, neomycin sulfate, the in vivo LLNA was able to detect the sensitizing capacity of test chemicals and was more sensitive than the in vitro LLNA for chemicals used in the present study. In another experiment, contact sensitivity was assessed by the ELISA to detect IFN-Υ from the supernatants of the cultured LNCs after sensitization with chemicals. There was a good correlation between the LLNA and the IFN-Υ production for test chemicals. We also examined the change of cell surface proteins on LNCs after sensitization by flow cytometry for some cell adhesion molecules(ICAM-1, E-cadherine, B7 molecule), T cell markers(CD3, CD4, CD8, T$\alpha$$\beta$,T${\gamma}$$\delta$) and B cell markers(LR1, CD45R, I-Ad). The number of ICAM-1 positive cells and B cells in LNCs were increased after sensitization with DNCB, TNCB, isoeugenol and 25%, 50% cinnamic aldehyde compared with that of vehicle as a control. In conclusion, the in vivo LLNA could provide more sensitive screening test for moderate to strong sensitizers and some weak sensitizers including cosmetic raw materials than the in vitro LLNA. The production of IFN-Υ by allergen-activated LNCs might be a values indicators without radioisotopes for the identification of contact allergens. Detection of allergens by testing the increase of ICAM-1 positive cells and B cells in LNCs by flow cytometry might be used as a test method to detect allergens.

• The Korean Journal of Physiology and Pharmacology
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• 제24권5호
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• pp.413-422
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• 2020

Delphinidin is a major anthocyanidin compound found in various vegetables and fruits. It has anti-oxidant, anti-inflammatory, and various other biological activities. In this study we demonstrated the anti-cancer activity of delphinidin, which was related to autophagy, in radiation-exposed non-small cell lung cancer (NSCLC). Radiosensitising effects were assessed in vitro by treating cells with a subcytotoxic dose of delphinidin (5 μM) before exposure to γ-ionising radiation (IR). We found that treatment with delphinidin or IR induced NSCLC cell death in vitro; however the combination of delphinidin pre-treatment and IR was more effective than either agent alone, yielding a radiation enhancement ratio of 1.54 at the 50% lethal dose. Moreover, combined treatment with delphinidin and IR, enhanced apoptotic cell death, suppressed the mTOR pathway, and activated the JNK/MAPK pathway. Delphinidin inhibited the phosphorylation of PI3K, AKT, and mTOR, and increased the expression of autophagy-induced cell death associated-protein in radiation-exposed NSCLC cells. In addition, JNK phosphorylation was upregulated by delphinidin pre-treatment in radiation-exposed NSCLC cells. Collectively, these results show that delphinidin acts as a radiation-sensitizing agent through autophagy induction and JNK/MAPK pathway activation, thus enhancing apoptotic cell death in NSCLC cells.

• 대한화학회지
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• 제20권3호
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• pp.236-239
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• 1976

광독성 물질인 쿠마린과 푸로쿠마린의 광화학반응을 분광분석, 삼중상태 켄칭, 형광법을 써서 연구하였다. 크산토톡신과 티민 또는 DNA 수용액의 광화학반응에서 ${\beta}$-카로텐을 켄치로 썼으나 아무런 켄칭이 일어나지 않는 것으로 보아 이 반응은 수명이 긴 크산토톡신의 삼중상태보다 수명이 짧은 들뜬 단일상태에서 일어나는 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.753-757
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• 2015

Recently, Lactobacillus rhamnosus GG (LGG) was shown to exert insulin-sensitizing and adiposity-reducing effects in high-fat (HF) diet-fed mice. In the present study, we observed that the effects were correlated with the extent of dysbiosis induced by HF diet feeding before LGG administration. LGG-treated mice were protected from HF diet-induced adiposity and/or insulin resistance when LGG was treated after, not along with, HF diet feeding. Results indicate that, under HF dietary condition, supplemented LGG reverses insulin resistance, but does not block its onset.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권2호
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• pp.79-84
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• 2000

The photodegradation of benzene was studied in an aqueous solution using a medium pressure Hg-lamp. In this study, persulfate, nitrate, nitrite, chloride, and sulfate ions were all tested as sensitizers. The persulfate, nitrate, and nitrite ions exhibited a sensitizing effect in the photodegradation of benzene, whereas no detectable effects were observed with the sulfate and chloride ions. When nitrite ions were used as the sensitizer, the photodegradation of benzene ran through a maximum value and thereafter decreased with an increasing nitrite concentration. The resulting build-up of nitrite ions seemed to scavenge the hydroxyl radicals. When nitrite ions were present along with persulfate ions, the photodegradation of benzene was inhibited.

• 한국세라믹학회지
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• 제30권5호
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• pp.339-346
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• 1993

Inproving laser efficiency, optimum content of Nd3+ which is active ion and effect of Cr3+ as a sensitizer are investigated in 60SiO2.30Li2O.10CaO host glass. The glasses are fabricated with the addition of Nd3+, Cr3+ and then optical properties such as absorption spectrum, fluorescence spectrum and fluorescence lifetime were studied. Finally, lasing efficiency was measured. From this study, optimum content of Nd2O3 appeared to be 3.5wt% and it was observed that the energy absorbed by optical exicitation of the Cr3+ is transfered to the Nd3+. Addition of Cr2O3 tend to improve characteristic of laser oscillation for the laser glass.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.117.1-117.1
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• 2011

We have demonstrated Forst-type resonance energy transfer (FRET) in the quasi-solid type dye-sensitized solar cells between organic fluorescence materials as an energy donor doped in polymeric gel electrolyte and ruthenium complex as an energy acceptor on surface of $TiO_2$. The strong spectral overlap of emission/absorption of energy donor and acceptor is required to get high FRET efficiency. The judicious choice of energy donor allows the enhancement of light harvesting characters of energy acceptor in quasi-solid dye sensitized solar cells which increase the power conversion efficiency. The enhanced light harvesting effect by the judicious choice/design of the fluorescence materials and sensitizing dyes permits the enhancement of photovoltaic performance of DSSC.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2007년도 춘계학술대회 및 국제감성 심포지엄
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• pp.98-100
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• 2007

네덜란드의 TU Delft에서는 컨텍스트 매핑 연구(Context mapping study)를 통해 사용자의 경험을 자연스럽게 얻어 낼 수 있는 방법을 제안해 왔다. 그러나 이 방법은 서양권에 있는 사용자들을 중심으로 연구 결과가 발표되었으며, 한국인이 대상이 된 논문에서는 일반인을 대상으로 한 실험 참여의 적극성 부족이라는 한계를 드러내었다. 본 사례 연구는 컨텍스트 매핑(Context mapping)을 한국 사용자들에게 실험설계를 하며, 이 전 연구들에게서 발견되었던 소극적 자기 표현 특성을 어떻게 개진할 수 있는지 연구하였다. 특히 컨텍스트 매핑(Context mapping)의 센시타이징(sensitizing) 단계에서 한국 사용자들에게서 발견되었던 사용자 조사 방법의 한계점을 다소 극복할수 있는 하나의 방안으로 제시할 수 있는 가능성이 발견되었다.

• 한국응용과학기술학회지
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• 제23권2호
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• pp.125-129
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• 2006

Benzoxazolo carbocyanine compounds were synthesized by condensation of a suitable ortho-ester with an appropriately substituted 2-methylbenzoxazole in the presence of triethylamine. This compounds used as green sensitizing dyes in photographic emulsions. The compounds are characterized by fast atom bombardment mass spectrometry. The values(m/z) of structurally significant ions observed in FAB spectra. It was showed tentative fragmentation pattern in FAB spectroscopy of $HN(C_2H_5)_3$ cations in glycerol/trifluoroacetic acid matrix.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.342.3-343
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• 2002

Non-insulin dependent diabetes mellitus (NIDDM) is characterized by hyperglycemia, hyperinsulinemia. and impaired insulin action. Insulin resistance is considered to be the underlying mechanism in the pathogenesis of type 2 diabetes. which also leads to dyslipidemia, hypertension. and obesity. Thazolidinediones are a class of oral insulin-sensitizing agents that improve glucose utilization without increasing insulin release. They significantly reduce glucose, lipid and insulin levels in rodent models of NIDDM and obesity, and recent clinical data support theri efficacy in obese diabetic patients. (omitted)