• 한방안이비인후피부과학회지
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• 제18권1호
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• pp.116-134
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• 2005

Although the parallel prescription of Sopoongsangagambang (SG) administration along with external treatment such as spraying or ointment application on the skin is clinically used for the treatment of atopic dermatitis (AD), molecular mechanism underlying its effectiveness is unknown. Thus in the present study, diverse immune responses in terms of chemical mediators related to AD were investigated using an atopic mouse model NC/Nga after SG administration and external treatment (ET), and major findings are summarized as follows. 1. The clinical severities in 16 and 20 week old NC/Nga mice with SG and ET treatment were decreased to 72.2% and 62.3% respectively compared to the control NC/Nga mice with no drug treatment. 2. IgE, IL-4, IL-5, IL-6, IL-13, IgM, IgG1 and IgG2a levels in the serum of SG and ET treated NC/Nga mouse group were significantly decreased compared to the untreated control mice. In contrast, $IFN-{\gamma}$ showed a significant increase in the experimental group compared to the untreated control group. 3. The spleen weight of SG and ET treated NC/Nga mice was significantly decreased compared to the untreated control group. 4. The B/T ratio in the lymph node of SG and ET treated NC/Nga mice was increased compared to the untreated control group. $CD4^+\;and\;CD8^+$ cell numbers in the lymph node of SG and ET treated NC/Nga mice were significantly increased compared to the untreated control group, but $CD69^+\;and\;CD11a^+$ cells were significantly decreased. 5. mRNA expression levels of IL-4, IL-5, and CCR3 in the skin tissues of SG and ET treated NC/Nga mice were significantly decreased, and expression levels of IL-6, IL-13, $CD69^+/CD3{\varepsilon}^+\;and\;CD19^+/CD44^+$ in the skin tissues of SG and ET treated NC/Mga mice were significantly decreased compared to the untreated control group. $IFN-{\gamma}$ mRNA expression levels were increased compared to the untreated control group. 6. Histological observation of the ear and neck skin tissues showed that the extents of inflammation and infiltrated immune cells in the epidermis and dermis of SG and ET treated NC/Nga mice were highly reduced compared to the untreated control group. 7. Lymphokine assay showed a significant decrease in IL-4 levels in SG and ET treated NC/Nga mice compared to the untreated control group, but the levels of $IFN-{\gamma}$ secretion were significantly increased drug treated NC/Nga mice.

• 한국수소및신에너지학회논문집
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• 제30권6호
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• pp.523-530
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• 2019

For the low-Pt electrodes for polymer electrolyte fuel cells (PEMFCs), the optimization of ionomer content for anode catalyst layers was carried out. A commercial catalyst of 20 wt.% Pt/C was used instead of 50 wt.% Pt/C which is commonly used for PEMFCs. The ionomer content varies from 0.6 to 1.2 based on ionomer to carbon ratio (I/C) and the catalyst layer is formed over the electrolyte by the ultrasonic spray process. Evaluation of the prepared MEA in the unit cell showed that the optimal ionomer content of the air electrode was 0.8 on the I/C basis, while the hydrogen electrode was optimal at the relatively high ionomer content of 1.0. In addition, a large difference in cell performance was observed when the ionomer content of the hydrogen electrode was changed. Increasing the ionomer content from 0.6 to 1.0 by I/C in a hydrogen electrode with 0.05 mg/㎠ platinum loading resulted in more than double cell performance improvements on a 0.6 V. Through the analysis of various electrochemical properties in the single cell, it was assumed that the change in ionomer content of the hydrogen electrode affects the water flow between the hydrogen and air electrodes bounded by the membrane in the cell, which affects the overall performance of the cell. A more specific study will be carried out to understand the water flow mechanism in the future, and this study will show that the optimization process of hydrogen electrode can also be a very important cell design variable for the low-Pt and high-performance MEA.

• 생물환경조절학회지
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• 제28권2호
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• pp.178-184
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• 2019

딸기는 세계적으로 중요하고 인기있는 과채류이며 '설향'은 국내 시장에서 재배되고 있는 주요 품종 중 하나이다. 딸기의 생장과 화아 유도는 이 작물의 과실에 수량에 직접적으로 영향을 미치는 과정이다. 본 연구에서는 벤질아데닌(BA), 지베렐린 산($GA_3$), 살리실 산(SA)이 '설향' 딸기의 생장과 화아 유도에 미치는 영향을 조사하였다. 21구 트레이에서 번식된 지 3주가 경과한 런너묘를 온도는 $25^{\circ}C/15^{\circ}C$(주간/야간), 상대습도는 70%, 광원은 백색 LED, 광도는 $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}\;PPFD$로 유지되는 생장 챔버에서 재배하였다. BA, $GA_3$ 및 SA를 각 0(대조구), 100, $200mg{\cdot}L^{-1}$로 런너묘에 처리하였다. 이러한 생장조절제를 런너묘의 잎에 2주 간격으로 2회 엽면살포하였다. 9주 후의 생육을 비교한 결과, 생장조절제를 엽면살포한 모든 처리에서 대조구에 비해 근장과 엽록소함량(SPAD)이 감소하는 경향을 보였다. $GA_3$ 처리에서 엽록소함량(SPAD)이 가장 낮았다. 하지만 $GA_3\;200mg{\cdot}L^{-1}$ 처리에서 엽면적, 잎 생체중, 식물 생체중이 증가하였다. 화아유도율과 화수는 $SA\;200mg{\cdot}L^{-1}$ 처리에서 각 85%와 식물체당 4.3개로 가장 높았고 그 다음으로 $SA\;200mg{\cdot}L^{-1}$ 처리에서 높았다. 전체적으로 $GA_3$ 처리에서 식물 생장을 향상시켰고, SA 처리에서는 개화를 촉진하였다. 더 나아가 $GA_3$와 SA를 혼합한 처리를 추가한 연구를 수행하여 생장조절제간의 관계를 구명하고 그 결과에서의 분자 메커니즘과 관련된 반응을 조사하는 것이 필요하다고 판단된다.