검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 49

        21.
        2008.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Intracellular pathogens must maintain redox homeostasis against the antimicrobial actions of reactive oxygen and nitrogen species produced by host cells. This study proves that glutathione is required to promote survival of an enteric pathogen Salmonella under the conditions producing reactive oxygen or nitrogen species. Glutathione is the non-protein thiol compound distributed in a variety of organisms and possesses strong electron-donating capability to reduce intracellular redox environment. To examine the role of glutathione on Salmonella redox homeostasis under oxidative and nitrosative stress conditions, gshB gene encoding glutathione synthetase was mutated by the one-step PCR inactivation method. The growth of gshB mutant Salmonella producing virtually no glutathione was greatly impaired in the culture media containing either hydrogen peroxide or nitric oxide donors. The results suggest that physiological levels of glutathione can provide a fundamental capability to maintain redox homeostasis for Salmonella in surviving oxidizing conditions of host cells.
        4,000원
        22.
        2007.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It prepared the TiO2 powder which has photo-catalytic activity in the visible-light by the wet process with titanium oxysulfate. The titanium dioxide(TiO2) by the wet process creates a new absorption band in the visible light region, and is expected to create photocatalytic activity in this region. Anatase TiO2 powder which has photocatalytic activity in the visible light region, is treated using microwave and radio-frequency(RF) plasma. But, the TiO2 powder for the visible light region, which also can be easily produced by wet process. The wet process TiO2 absorbed visible light between 400nm and 600nm, and showed a high activity in this region, as measured by the oxidation removal of aceton from the gas phase. The AH-380 sample appears the yellow color to be strong, the catalytic activity in the visible ray was excellent in comparison with the plasma-treated TiO2. The AH-380 TiO2 powder, which can be easily produced on a large scale, is expected to have higher efficiency in utilizing solar energy than the plasma-treated TiO2 powder.
        4,000원
        24.
        2004.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 돼지 태아 섬유아세포유래 공여세포를 미세주입에 의해 주입 후 재 조합한 핵 이식 배에 대한 배양액, 세포주기의 동기화, 배양시간 및 난자의 활성화에 따른 융합율과 체외발생율에 대해 조사하였다. 핵 이식 배를 NCSU-23, TL Hepes 및 TZM-3 배양액으로 1시간 및 8시간 배양하였을 때 배반포로의 분할율은 각각 15.6%, 14.0%, 15.0% 및 13.9%, 10.5%, 13.3%로서 배양액 및 시간에 따른 분할율의 유의적인 차이
        4,000원
        26.
        2002.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        양강추출물(Alpinia officinarum, 70% ethanol extract)과 함유 주성분인 galangin은 프리라디칼소거작용과 지질과산화억제활성을 나타내었으며, H_2O_2 또는 KO_2유도 세포독성에 대해서도 억제적으로 작용하여 세포보호효과를 나타내었다. DNA single strand breakage와 같은 산화적 스트레스에 대해서도 보호작용을 하고 있다. 또한, 마우스 소핵시험에 의하여 adriamycin과 같은 superoxide유발물질에 의한 염색체 수준에서의 손상에 대해서도 억제효과를 나타내었다. 양강추출물은 galangin을 유효성분으로하여 산소프리라디칼들에 의한 산화적 손상에 억제적으로 작용하는 기전으로 산화적 스트레스에 대한 항노화, 암예방제로서의 응용가능성이 높은 추출물로서 향후 기능성 식품으로서의 응용가능성이 높을 것으로 판단되었다.
        4,200원
        30.
        2017.05 서비스 종료(열람 제한)
        Background : The young stem of Cinnamomum cassia (YSC) as traditional Chinese medicines has been reported to show a variety of pharmacological properties such as anti-allergy, insecticidal, antimicrobial, antiulcer, anti-inflammatory, immune-suppressive, and neuronal death prevention, tyrosinase inhibition and anticancer, antioxidant and free radical scavenging, as well as antidiabetic and aldose reductase inhibition activities. In this study, we elucidated apoptotic effect and potential molecular mechanism of hot water extracts from YSC (YSC-HW) against human colorectal cancer cells. Methods and Results : YSC-HW treatment increased ROS level and induced ROS-dependent DNA damage in human colorectal cancer cells. ROS generation mediated by YSC-HW induced DNA induced apoptosis and reduction of cell viability in human colorectal cancer cells. YSC-HW ROS-dependently induced NF-kB activation through p65 nuclear translocation via IkB-α degradation, which exerted the induction of apoptosis. In addition, YSC-HW activated ATF3 expression dependent on ROS, which resulted in apoptosis. Conclusion : Our results suggest that YSC-HW may induce apoptosis through ROS-activation of NF-kB and ATF3 in human colorectal cancer cells. From these findings, YSC-HW has potential to be a candidate for the development of chemoprevention or therapeutic agents for human colorectal cancer.
        31.
        2017.05 서비스 종료(열람 제한)
        Background : We have previously reported that Oligonol, a low-molecular polyphenol derived from lychee fruit, has protective effect on the liver and kidney of diabetic animal model. In this study, we examined whether Oligonol has any beneficial effects on pancreas of diabetic rats. Methods and Results : Oligonol was orally administered at a dose of 10 and 20 mg/kg body weight for 10 days to STZ-induced diabetic rats, and the effects were compared with those of vehicle-treated diabetic control and non-diabetic control rats. The administration of Oligonol reduced hyperglycemia in diabetic rats through an improvement of serum and pancreatic insulin levels. The increased reactive oxygen species levels in pancreas of diabetic control rats was attenuated by the Oligonol administration through inhibiting the expression of NADPH oxidase-related proteins. The enhanced expression of pro-apoptotic proteins in pancreas of diabetic control rats was significantly reduced by Oligonol administration through down-regulation of phosphor-c-Jun N-terminal kinases protein in pancreas. Furthermore, the expressions of cell proliferation-related protein were also augmented in Oligonol treated-diabetic rats. However, Oligonol treatment led to improved histological changes in the pancreas. Conclusion : These pancreatoprotective effects of Oligonol were achieved through attenuation of oxidative stress and its sensitive protein expression associated with apoptosis and cell proliferation in diabetic rats.
        32.
        2016.10 서비스 종료(열람 제한)
        Background : ROS produced by oxidative stress damaged endothelial cells, and cause a variety of vascular complications. In diabetic hyperglycemia state, ROS increase. The polyol pathway occur in diabetic complications, the excess glucose is absorbed into the polyol pathway when aldose reductase increased, NADPH changes it to sorbitol. Glutathione (GSH) removes ROS. GSH level is reduced by glutathione reductase, using NADPH as an electron donor. Activation of the polyol pathway decrease NADPH, and GSH also reduced. As a result, ROS is increased. In diabetic hyperglycemia state, Glycolysis increases. Effects of increased glycolysis, protein kinase C (PKC) is increased. NAD(P)H oxidase, stimulated by PKC-dependent pathway, increases ROS in the cell. In this study, we measured the ROS scavenging activity of 5 natural products (Lycii fructus, Astragalus membranaceus, Cassia Tora, Polygonatum odoratum, Rubus Coreanus), to confirm the efficacy as diabetic antioxidants. Methods and Results : We extracted 5 natural product by distilled water and ethanol. DPPH radical scavenging activity was significantly higher in Lycii fructus, Rubus coreanus. ABTS radical scavenging activity was better Rubus coreanus, Lycii fructus, Cassia Tora. In addition to, Rubus coreanus, Cassia Tora, Lycii fructus was comparatively higher reducing power activity than other natural products. And total phenolic and flavonoid contents were much higher in Rubus coreanus compared with other extracts. Conclusion : These results suggest that Lycii fructus, Rubus coreanus can be applied as diabetic antioxidant that prevent vascular complications caused by ROS.
        33.
        2016.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구는 4종의 별의별간(SS) 음료의 간보호 소재로서 의 이용 가능성을 조사하고자 항산화능 평가, t-BHP 와 CCl4로 산화적 손상 및 급성 간독성 유도한in vitro, in vivo 모델을 활용하여 간보호능을 평가하였다. 실험결과, 별의별간 01~04는 50 μM vitamin C 와 유사한 항산화 효과를 나타내었다. HepG2 세포에 t-BHP로 산화 스트레스를 유도한 뒤 나타나는 세포독성에 대해 별의별간 01 및 04에서 농도 의존적인 세포 보호효과를 보였으며, ROS 생성 억제에서 별의별간 01, 03, 04에서 농도의존적인 억제를 나타내었다. 미나리가 혼합된 별의별간 04에 대한 급성 간손상in vivo 모델을 활용하여 간보호능 검증 결과, 별의별간 04는 CCl4로 증가된 혈중 ALT, AST의 유의적 감소, 간 조직중 증가된 MDA 함량 감소 및 감소된 GSH의 유의적 증가를 나타내었다. 또한, 혈청 및 간 조직에서 증가 된 중성지방과 콜레스테롤을 유의적으로 감소시켰다. 이러 한 결과를 종합하며, 별의별간 04는in vitro 및in vivo 모델 에서 산화적 손상에 대해 간보호 효과를 나타내었다
        35.
        2010.12 KCI 등재 서비스 종료(열람 제한)
        본 연구는 유산소운동능력의 차이를 보이는 두 집단이 각각 로윙에르고미터 최대하 운동을 실시한 후 혈중 활성산소의 변화에 어떠한 차이를 나타내는지 구명하는데 목적이 있으며 연구대상으로는 조정 선수집단 6명과 비선수집단 6명을 대상으로 최대유산소운동능력을 검사한 후 각각의 목표심박수 85~90%를 적용하여 로윙에르고미터 운동을 실시하였고 운동 전, 직후, 10분, 20분, 차30분에 각각 채혈하여 활성산소의 변화를 분석하였다. 그 결과는 유산소운동능력의 차이에 따른 활성산소의 변화에서 집단과 시기 간 상호작용 효과는 유의한(p<.05) 차이를 나타내어 시기에 따른 변화의 양상이 집단 간 차이가 있었고 사후검증 결과 회복기 10분에서 20분 그리고 20분에서 30분 구간에서 유의한 차이가 나타났다. 결론적으로 인체에 부정적인 영향을 미치는 활성산소로부터 유산소운동능력이 우수한 조정선수집단이 비선수집단에 비해 긍정적인 회복 패턴을 보였다.
        36.
        2010.10 KCI 등재 서비스 종료(열람 제한)
        활성산소종(reactive oxygen species, ROS)인 glucose oxidase(GO)의 산화적 손상이 배양 C6glioma 세포에 미치는 영향 및 이에 대한 연꽃(Nelumbo nucifera GAERTN, NNG) 추출물의 항산화 효과를 세포생존율(cell viability)을 비롯한 DPPH-radical scavenging activity, lipid peroxidation에 의하여 분석하였다. 본 연구에서 H2O2는 배양 C6 glioma세포에 처리한 농도에 비례하여 유의한 세포생존율의 감소를 나타냈다. 한편, GO의 산화적 손상에 대한 NNG추출물의 방어효과를 조사하기 위하여 세포생존율을 조사한 결과 NNG 추출물은 GO의 산화적 손상으로 감소된 세포생존율을 유의하게 증가시켰다. 또한, NNG 추출물은 DPPH-radical scavenging activity의 분석에서 유의한 자유라디칼 소거능을 보였으며, 동시에 지질과산화에 대한 억제능을 보였다. 위의 결과로 부터 GO는 배양 C6 glioma세포에 고독성인 것으로 나타났으며 NNG추출물은 GO와 같은 ROS의 산화적 손상을 방어하는데 효과적인 것으로 나타났다.
        37.
        2010.05 KCI 등재 서비스 종료(열람 제한)
        Rapid industrialization has brought Nam-Hae area serious environmental problems associated with released oil and other hydrocarbons. In this work, in order to enhance the quality of the shoreline sediment we made enviro-chemical analyses of its substances, TPHs and microbial growth after treating with oxygen releasing compound(ORC) such as MgO2. Total organic compound(TOC) was reduced from 33.45% to 25.1∼31.08% meanwhile COD decreased from 27.5∼28.9mg/g·dry to 19.9∼26.1mg/g·dry for input of 2∼10% MgO2 in 20days. For 10% MgO2 input, TP and TN were reduced by 13.3% and 18.8%, respectively. Most of all TPH was decomposed by max. 42.4% in 21days, and the total viable count of microbes was found to be exponentially increased by 75.9%.
        38.
        2009.02 KCI 등재 서비스 종료(열람 제한)
        본 연구는 t-butyl hydroperoxide(t-BHP)의 산화적 손상에 대한 원지(Polygalae Radix, PR)추출물의 항산화 효과를 알아보기 위하여 배양 C6 glioma 세포를 재료로 세포생존율을 비롯하여 superoxide dismutase(SOD) 유사 활성을 비롯하여 lactate dehydrogenase(LDH) 활성을 조사하였다. 본 실험에서 t-BHP는 농도 의존적으로 배양 C6 glioma 세포의 생존율을 유의하게 감소시켰다. 한편, t-BHP의 세포독성에 대한 원지 추출물의 항산화 효과의 정량분석에 있어서 원지 추출물은 t-BHP의 산화적 손상으로 감소된 세포생존율의 유의한 증가를 비롯하여 LDH 활성감소 및 SOD 유사 활성을 보임으로서 항산화 효과를 나타냈다.
        39.
        2008.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The propose of this study was to investigate the antioxidant activity of 80% ethanol extracts and various solvent fractions of dandelion (Taraxacmn officinale) leaves and roots, Total phenolics and phenolic acid contents were also examined. The total phenol content of leaves and roots were and respectively. Eight phenolic acids were separated by GC, among which caffeic acid (113.7 mg%)and m-coumaric acid (152.6 mg) were the dominant phenolic acids in leaves and roots, respectively. Amongst solvent functions of leaves and roots, the ethyl acetate fraction showed the strongest radical scavenging activity. A strong correlation was found between total phenol content and electron-donating ability, and ABTS radical scavenging activity showed a similar trend as electron-donating ability. Hydroxyl-radical-scavenging activity and lipid peroxidation were significantly higher in the ethyl acetate fraction than other factions. In particular, the SOD-like activity was highest (43.6%) in the ethyl acetate fraction of dandelion leaves, and was higher than that of trolox. Thus, the ethyl acetate fraction of dandelion leaves exhibited significant phenol content, antioxidant activity, and free-radical-scavenging effects.
        1 2 3