• Radiation Oncology Journal
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• v.23 no.4
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• pp.211-216
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• 2005

Purpose: It has been reported that all-trans retinoic acid (ATRA) can inhibit glioma growing in vitro. However, clinical trials with ATRA alone in gliomas revealed modest results. ATRA has been shown to increase radiosensitivity in other tumor types, so combining radiation and ATRA would be one of alternatives to increase therapeutic efficacy in malignant gliomas. Thus, we intended to know the role of catalase, which is induced by ATRA, for radiosensitivity if radiation-reduced reactive oxygen species (ROS) is removed by catalase, the effect of radiation will be reduced. Materials and Methods: A rat glioma cell line (36B10) was used for this study. The change of catalase activity and radiosensitivity by ATRA, with or without 3-amino-1, 2, 4-triazole (ATZ), a chemical inhibitor of catalase were measured. Catalase activity was measured by the decomposition of $H_2O_2$ spectrophotometrically Radiosensitivity was measured with clonogenic assay. Also ROS was measured using a 2, 7-dichlorofluorescein diacetate spectrophotometrically. Results: When 36B10 cells were exposed to 10, 25 and $50{\mu}M$ of ATRA for 48 h, the expression of catalase activity were increased with increasing concentration and incubation time of ATRA. Catalase activity was decreased with increasing the concentration of AT (1, $10{\mu}M$) dose-dependently. ROS was increased with ATRA and it was augmented with the combination of ATRA and radiation. ATZ decreased ROS production and increased cell survival in combination of ATRA and radiation despite the reduction of catalase. Conclusion: The increase of ROS is one of the reasons for the increased radiosensitivity in combination with ATRA. The catalase that is induced by ATRA doesn't decrease ROS production and radiosensitivity.

• 대한위암학회:학술대회논문집
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• 2002.04a
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• pp.9-17
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• 2002

위의 parietal cell 혹은 대식세포와 유사한 세포 내부에서 H. pylori가 발견된다는 보고가 있기는 하나 일반적으로 H. pylori는 Shigella와 같은 침습성 세균은 아닌 것으로 알려져 있다. 그럼에도 불구하고 H. pylori에 감염된 위점막에는 많은 수의 호중구를 위시한 염증세포의 침윤이 관찰되는데 H. pylori가 위상피세포에 부착 할 경우 위상피세포를 자극하여 interleukin-8을 위시한 cytokine 을 발현케하고 이에 의하여 호중구 등의 염증세포가 몰려들게 된다. 한편 고유층에 몰려든 호중구에서는 다시 interleukin-8을 위시한 일련의 호중구 활성화 chemokine을 분비하여 염증반응을 증폭해 나갈 것이다. 호중구에서 발현되는 myeloperoxidase나 활성 산소 등도 위점막의 조직 손상에 기여할 것이다. 위상피세포를 덮고 있는 점액층은 위상피세포를 보호한다고 알려져 있으나 H. pylori 감염의 경우 점액층에 의하여 H. pylori의 운동성이 증가하고 이것이 위상피세포로부터의 cytokine 발현을 자극하여 염증반응을 증폭하는데 관여할 가능성도 있다. H. pylori는 위상피세포에 대하여 apoptosis를 유도함과 동시에 고유층에 몰려든 호중구에 대하여는 apoptosis를 억제케하여 궁극적으로 염증반응을 증폭 및 지속시켜 나가는 쪽으로 작용한다. 한편 H. pylori는 위상피세포로부터 COX-2의 발현을 증가시키는데 이는 위상피세포의 apoptosis를 억제하는 방향으로 작용한다. 이외에 H. pylori의 urease에 의하여 발생한 암모니아나 H. pylori 자신이 분비하는 세포독소가 세포 손상을 유발할 가능성도 있다. 상술한 여러 독성 인자들 중 어느 하나가 단독으로 작용하기보다는 여러 인자가 같이 동시에 또는 시차를 두고 작용할 가능성이 많다고 생각된다.(\gamma-FeOOH)$, 침철광$(\alpha-FeOOH)$, 적금광$(\beta-FeOOH)$, 그리고 자철광$(Fe_3O_4)$이다. 인위적 부식에서는 전부 인철광의 부식물이 생성되었고 자연적 부식에서는 모두 침철광의 부식물이 생성되었다. 특히 철제 표면에 자연적으로 생성된 공식 녹을 XRD 분석한 결과 적금광으로 동정되었다. 이런 모든 시편들을 각 탈염방법에 따라 탈염처리한 후 XRD와 SEM-EDS으로 분석한 결과 인철광과 침철광은 어떠한 변화도 보이지 않았고, 다만 적금광으로 동정된 시편만이 잔존하지 않았다. 철기 제작별 $Cl^-$ 이온 추출량과 탈염효과에 대한 비교 실험은 이온 크로마토그래피 분석 결과와 마찬가지로 단조 철제유물이 주조 철제보다 $Cl^-$ 이온을 많이 가지고 있었으며, 탈염 처리 후에는 $Cl^-$ 이온은 전혀 발견되지 않았다. 이상의 결과 $K_2CO_3$와 Sodium 용액은 탈염처리에서 가장 적합한 탈염처리 용액으로 알수가 있었으며 특히 어떠한 탈염 용액으로 유물을 처리한다 해도 철제유물에 생성된 부식물은 제거되지 않는다는 것을 알게 되었다. 따라서 보존처리자는 유물 표면의 부식 상태만을 보고 처리하기 보다는 철기제작물로 고려하여 처리하는 것이 필요하다. 또한 금속에 부식을 야기시키는 $Cl^-$ 이온과 부식물을 완전하게 제거하여 탈염처리를 하는 것이 유물 부식을 최대한 지연시킬 수 있는 것이라 생각된다.TEX>$88\%$)였다.(P=0.063). 결론: 본 연구에서는 MTHFR C/T & T/T 유전자 다형성이 위암의 발생과 그 위치에 대해 관련이 있는 것으로 여겨지고, 흡연력, 음주력과는 관련이 없는 것으로 여겨진다.험이

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.49.1-49.1
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• 2011

집광채광 설비는 건축물의 조명에너지 절감 및 자연광의 실내 유입을 위해 적용 가능한 태양에너지설비로써 다른 신 재생 에너지 설비와 다르게 연간에너지생산에 대한 정량적 데이터가 아직까지 부재하다. 집광채광 설비의 설치효과를 판단하기 위해서는 집광채광 설비 설치에 따른 연간 에너지생산량 산출이 필요하며, 이를 위해서는 각 구성부분(집광부, 전송부 및 산광부)의 광전송 효율에 대한 데이터가 구축되어야 한다. 본 연구는 집광채광 설비의 효율 분석에 관한 첫 번째 단계로써 외부광속에 대한 집광부 통과 직후의 내부광속의 비율을 예측하였다. 국내에 보급된 집광채광 설비는 대부분 프리즘형과 광덕트형이며, 우선적으로 집광부 입사면의 경사각과 방위각이 다양하여 내부광속 산출방법론이 매우 복잡한 프리즘형을 분석대상으로 삼았다. 전일사량, 외부조도 및 집광부 내부조도가 측정되었으며, 외부광속으로부터 내부광속을 산출하는 공식을 유도하기 위해 천공상태에 따라 전일사량 측정치가 직산분리 되었다. Perez model과 Liu and Jordon에 의해 제시된 계산식과 입사면 및 집광부 면적을 고려하여 수평면 외부조도 측정치로부터 외부광속이 그리고 내부조도로부터 내부광속이 산출되었다. 입사면의 투과율이 동일하다는 전제 하에 천공상태에 따른 태양광 투과 비율을 도출한 결과, 담천공(Kt ${\leq}$ 0.3)에서 0.39, 부분담천공(0.3${\geq}$ 0.78)에서 1.0으로 나타났다. 도출된 투과비율을 외부광속에 적용하여 내부광속을 계산한 결과치와 측정치는 약 ${\pm}9%$ 정도의 차이를 보였다. 연간 기상데이터에 위와 같은 방법론이 적용되면 프리즘형 집광부의 연간 내부광속이 산출될 수 있다. 또한 기존 연구에서 제시된 발광효율 산출식과 일사 파장에 따른 시감도를 고려하면 매 시간별 외부조도도 산출이 가능하다. 일사량 측정치와 외부조도 측정치 사이의 상관관계를 분석한 결과 결정계수 $R^2$이 0.99인데 반해 일사량 측정치와 외부조도 계산치 사이의 상관관계 결정계수는 0.95로 측정치 보다 약간 작은 값을 갖는다. 이렇게 산출된 외부조도는 각 입사면의 면적을 반영하여 외부광속으로 변환되고, 앞서 산출된 천공상태별 투과비율이 적용됨으로써 내부광속이 도출될 수 있다. 이와 같은 집광부에 대한 연구를 바탕으로 향후 전송부와 산광부 효율을 도출하고 궁극적으로 집광채광 설비를 통해 실내에 전달되는 연간 빛에너지를 예측할 수 있을 것이다. 또한 본 연구의 방법론은 다른 형태의 집광채광 설비에도 적용이 가능할 것으로 판단되며, 국내 집광채광 설비의 연간 에너지생산량에 대한 폭 넓은 데이터 구축이 가능할 것으로 기대된다.

• Korean Journal of Optics and Photonics
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• v.22 no.2
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• pp.67-71
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• 2011

In the paper, we have demonstrated an azobenzene-coated fiber Bragg grating (FBG) for monitoring ultraviolet light (UV) intensity in remote measurement. The elasticity of the coated azobenzene polymer is changed by the UV light, which induces a center wavelength change corresponding to the change of the FBG's grating period. The wavelength shift resulting from both UV light and other light with the wavelength out of the UV range was about 0.18 nm. In order to improve the accuracy of the measurement, the center wavelength shift caused by radiant heat of the light source was sufficiently removed by using a thermal filter. The amount of the center wavelength shift was consequently reduced to 0.06 nm, compared to the result without the thermal filter. Also, the FBGs coated by using azobenzene polymer were produced by two different methods; thermal casting and UV curing. Considering temperature dependence, UV curing is more suitable than thermal casting in UV sensor application of the azobenzene-coated FBG. In addition, we have confirmed the wavelength dependence of the optical sensor by means of four different band pass filters. Thus, we found out that the center wavelength shift per unit intensity is 0.029 [arb. unit] as a maximum value at 370 nm wavelength region and that the absorption spectrum of the azobenzene polymer was very consistent with the wavelength dependence of the azobenzene-coated FBG.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.132-138
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• 2003

This experiment was conducted to investigate the mass propagation system of Aster glehni FR. and to obtain the basic data for improvement of germination and seedling. The following was the results of experimentation about temperature and light conditions, and priming treatment as kinds of chemicals, their concentration and treated periods affect germination of Aster glehni FR. The germination percentage of Aster glehni FR. seed was higher in 20 and 25$^{\circ}C$ than the others, but it dropped rapidly at 30$^{\circ}C$ and didn't germinate at 35$^{\circ}C$. The first day to germination was the slowest at 15$^{\circ}C$. The germination rate of Aster glehni FR seed increased with increasing with temperatures from 15 to 25$^{\circ}C$. But the seed was rotten easily in high temperature. The germination rate was shown highest in 25$^{\circ}C$, and next was 15, 20, 30$^{\circ}C$ in order. Light treatment enhanced germination percentage, the first day to germination, germination rate and T50, but there was no significant difference. The 3 hours priming treatments had more effect on germination percentage than 30 minutes treatments as comparing averages. Aster glehni FR seeds primed in $KNO_3+K_3PO_4$ for 3 hours had most eHective on germination percentage (83.3%) and also showed shortest $T_{50{\cdot}}T_{50}$ and day of first germination was better in 30 minutes than 3 hours treatments, and most of priming treatments were better than control(non-priming seeds). While priming seeds showed shorter day of first gemination than control, there was no significant difference between 30 minutes and 3 hours treatments.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.351-359
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• 2015

Acute and chronic ultraviolet (UV) irradiation triggers severe skin photoaging processes, which directly disrupt the normal three-dimensional integrity of skin. UV light stimulates the expression of matrix metalloproteinases (MMPs) which degrade constituents of extracellular matrix (ECM) proteins. These MMPs reduce collagen synthesis and decrease skin elasticity and integrity, resulting in wrinkle formation. In this study, we identified Rosa multiflora hip extract (RME) as an effective anti-photoaging ingredient. First, cell proliferation activity of RME was verified using Hs68 human dermal fibroblast cell line. RME downregulated MMPs expression through the inhibition of activator protein (AP)-1. In addition, type I and IV collagen expressions were increased with RME treatment and UVB-induced inflammatory responses were also reduced after RME treatment. In conclusion, R. multiflora hip extract may effectively improve UVB-induced skin aging and wrinkle formation which may provide as an anti-aging, anti-wrinkle, and anti-inflammation ingredient in cosmetic industry.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.176-184
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• 2018

In the present study, we investigated the antioxidative properties, cellular protective effects and component analyses of 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from Lysimachia christinae Hance (L. christinae Hance). In the evaluation of antioxidative properties, the free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction and aglycone fraction were 146.8, 22.2 and $27.2{\mu}g/mL$, respectively and total antioxidant capacities ($OSC_{50}$) were 29.3, 2.9 and $4.5{\mu}g/mL$, respectively. The ethyl acetate fraction showed the highest free radical scavenging activity and total antioxidant capacity. Also, the cellular protective effects (${\tau}_{50}$) of 50% ethanol extract, ethyl acetate fraction and aglycone fraction on $^1O_2$ induced photohemolysis of human erythrocytes were 26.9, 57.5 and 103.9 min at $5{\mu}g/mL$, respectively. In particular, ${\tau}_{50}$ of the aglycone fraction exhibited a higher cellular protective effect than that of (+)-${\alpha}$-tocopherol (37.7 min). The cell viability of the ethyl acetate fraction on the UVB-induced cell damage increased up to 90.1%. In addition, the ethyl acetate fraction ($5-25{\mu}g/mL$) showed cellular protective effects on the $H_2O_2-induced$ cell damages in a dose-dependent manner. TLC, HPLC, UV-vis spectroscopy and LC-MS were used to analyse components of the ethyl acetate fraction and the main components were quercetin, kaempferol and their glycosides. In conclusion, L. christinae Hance extract/fraction can function as antioxidants to protect the skin exposed to UV radiation and may also be used as a novel functional cosmetic material, for example, an antioxidant against skin photoaging.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.395-399
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• 1997

Meat model emulsions ware prepared with salt-soluble protein and soybean oil. Effects of water-soluble protein (WSP) on the meat model emulsion treated with/without BHT during 8 day storage $5^{\circ}C$ under both dark and light illumination were studied by measuring POV and TBA. An emulsion without BHA and WSP was used as a control. Under light storage, there was no significant difference in peroxide values between the control and the sample treated with BHA except the 2nd day of storage. However, TBA values of the sample treated with BHA were significantly (p<0.05) lower than those of control except the 4th day of storage. TBA and POV of the samples treated with WSP and WSP + BHA were higher than control after 4th day of storage under light. That is, water soluble protein, which was composed mainly of myoglobin, increased lipid oxidation under light storage. The similar trends were also shown in the samples stored under dark. These results suggested that acceleration of lipid oxidation of the meat model emulsions by water soluble protein (WSP) under both light and dark might not be due to the singlet oxygen formation, but due to superoxide anion formed.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.189-196
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• 2001

Objective : We tested the hypothesis that photodynamic therapy(PDT) with Photofrin inhibits tumor invasion of U87 human glioma cells using several in vitro assay to measure tumor invasiveness. The effects of PDT on cell growth, directional migration and cell invasion were investigated. Material and Method : Tumor cells were treated with Photofrin at various doses and at a fixed optical(632nm) dose of $100mJ/cm^2$. Cytotoxicity was tested using the MTT method. Invasion assays including the matrigelartificial basement membrane barrier migration and spheroid confrontation with confocal microscopic analysis were used to study the relationship between PDT and invasiveness. Result : U87 cells showed a dose dependent cytotoxic response to increasing Photofrin dose. Data from the matrigel artificial basement membrane assay indicate that PDT inhibits the U87 cell migration dose dependently. Low doses of subcytotoxic PDT treatment, such as 2.5ug/ml Photofrin dose, also appeared to significantly inhibit migration of U87 cells(p<0.05). In co-cultures between U87 cell spheroids and brain aggregates, progressive invasion with destruction of the brain aggregate occurs. The extent of tumor cell infiltration and proportion or intact brain aggregate remaining after 24h differs in Photofrin PDT treated versus Photofrin only control, with changes suggestive of a dose-response effect. Conclusion : our data indicate that PDT with Photofrin significantly inhibits the invasiveness of U87 cells, and this inhibition is dose dependent.

• Journal of Life Science
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• v.27 no.6
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• pp.680-687
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• 2017

Recently, there has been a marked increase in the use of bioactive products resulting from the fermentation of natural substances by microorganisms. In this study, Opuntia humifusa (OH) was fermented using Lactobacillus plantarum (fermented Opuntia humifusa; fOH). We then examined the anti-obesity effect of fOH in mice fed a 45% Kcal high fat diet (HFD). In this study, mice were treated with fOH concentrations of 100, 200, and 400 mg/kg. The mice in the control group were treated with OH at a concentration of 400 mg/kg based on previous animal experiments. All of the mice given a continuous HFD showed an increase in their weight, the density of abdominal fat, and the accumulated periovaric and abdominal fat. All of these obesity-linked factors, however, were significantly decreased in the groups treated with fOH at concentrations of 200 and 400 mg/kg. Mice treated with fOH at 100 mg/kg did not show a significant decrease in these obesity-linked factors compared to the control group. It appears that fOH fermented by L. plantarum has a greater anti-obesity effect in HFD-supplied mice compared to unfermented OH. While further studies of fOH are needed to examine its effect on obesity, hyperlipidemia, hepatic steatosis, renal function, and type II diabetes with its relevant complications, fOH may have significant therapeutic potential in the treatment of metabolic syndrome.