• Title/Summary/Keyword: Protective systems

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Effects of T-2 Toxin, Zeolite and Mycosorb on Antioxidant Systems of Growing Quail

  • Dvorska, J.E.;Surai, P.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1752-1757
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    • 2001
  • The present study was conducted to assess the dietary effect of T-2 toxin on the antioxidant systems of the liver in growing quail and to comparatively evaluate the protective properties of two different mycotoxin-adsorbent additives, Mycosorb and zeolite, in preventing inhibition of the antioxidant system. Four groups of 4 day old quail were formed with 20 birds in each group. The birds were maintained on the floor for the course of the study. The three treatment diets consisted of the basal diet with T-2 toxin added in the form of Fusarium sporotrichioides culture (8.1 mg/kg feed), T-2 toxin (8.1 mg/kg) plus zeolite (30 g/kg feed), and T-2 toxin (8.1 mg/kg) plus Mycosorb (1 g/kg feed). After 30 days of feeding (34 days old) all birds were sacrificed and liver samples for biochemical analyses were collected from five quail in each of the four groups. Antioxidant concentrations were evaluated by HPLC-based methods. Inclusion of T-2 toxin in the quail diet was associated with a significant (p<0.05) decrease in concentrations of all forms of antioxidants studied, including ${\alpha}$- and ${\gamma}$-tocopherols, ascorbic acid, retinol and retinyl esters. At the same time, liver susceptibility to lipid peroxidation significantly (p<0.05) increased. Inclusion of zeolite in the quail diet at the level of 3% was ineffective in preventing antioxidant depletion in the liver by mycotoxicosis. In contrast, Mycosorb in the diet at a 0.1% level was able to significantly inhibit liver antioxidant depletion and as a result decreased lipid peroxidation in the liver. Concentrations of all forms of antioxidants studied were significantly higher in the livers of the quails fed the basal and T-2 toxin/Mycosorb combination in comparison to birds fed the basal with T-2 toxin alone.

The Structural Relationships among Information Security Threat Factors and Information Protection Behavior of the FinTech Services: Focus on Theoretical Perspectives of Technology Threat Avoidance and Health Protective Behaviors (핀테크(FinTech) 서비스의 정보보안 위협요인과 개인정보보호행위와의 구조적 관계에 관한 연구: 기술위협회피와 건강행동이론 관점에서)

  • Bae, Jae Kwon
    • The Journal of Information Systems
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    • v.26 no.3
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    • pp.313-337
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    • 2017
  • Purpose Financial technology, also known as FinTech, is conceptually defined as a new type of financial service which is combined with information technology and other traditional financial services like payments, investments, financing, insurance, asset management and so on. Most of the studies on FinTech services have been conducted from the viewpoint of technical issues or legal and institutional studies, and few studies are conducted from the health belief perspectives and security behavior approaches. In this regard, this study suggest an extended information protection behavior model. Design/Methodology/Approach The Health Belief Model (HBM), the Protection Motivation Theory (PMT), and the Technology Threat Avoidance Theory (TTAT) were employed to identify constructs relevant to information protection behavior of FinTech services. A new extended information protection behavior model in which the influence factors of information protection behavior (i.e., perceived susceptibility, perceived severity, perceived benefits, perceived barriers, perceived self-efficacy, subjective norms) affect perceived threats and perceived responsiveness positively, leading to information protection behavior of FinTech users eventually. This study developed an extended information protection behavior model to explain the protection behavior intention in FinTech users and collected 272 survey responses from the mobile users who had experiences with such mobile payments and FinTech services. Findings The finding of this study suggests that the influence factors of information protection behavior affect perceived threats and perceived responsiveness positively, and information protection behavior of FinTech users as well.

Pharmacology of enantiomers of higenamine and related tetrahydroisoquinolines

  • Park, Min-Kyu;Huh, Ja-Myung;Lee, Young-Soo;Kang, Young-Jin;Seo, Han-Geuk;Lee, Jae-Heun;Park, Hye-Sook-Yun-;Lee, Duck-Hyung;Chang, Ki-Churl
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2004.04a
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    • pp.3-10
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    • 2004
  • Oxidative stress is a constant threat to all living organisms and an immense repertoire of cellular defense systems is being employed by most pro- and eukaryotic systems to eliminate or to attenuate oxidative stress. Ischemia and reperfusion is characterized by both a significant oxidative stress and characteristic changes in the antioxidant defense. Heme oxigenase-l (HO-l) is up-regulated by various stimuli including oxidative stress so that it is thought to participate in general cellular defense mechanisms against ischemic injury in mammalian cells. Higenamine, an active ingredient of Aconite tuber, has been shown to have antioxidant activity along with inhibitory action of inducible nitric oxide synthase (iNOS) expression in various cells. In the present study, we investigated whether higenamine and related analogs protect cells from oxidative cellular injuries by modulating antioxidant enzymes, such as HO-l, MnSOD etc. R-form of YS-51 was the most potent inducer of HO-l in bovine endothelial cells, which inhibited apoptotic cell death by H$_2$O$_2$. HO-1 induction by YS 51 was mediated by PI3 kinase activation in which PKA- as well as PKG pathway is considered as important regulators. YS-51 also induced Mn-SOD mRNA expression by activating c-jun N-terminal kinase in endothelial cells and Hela cells. In ROS 17/2.1 cells, higenamine and enetiomers of related compounds inhibited iNOS expression by cytokine mixtures. Taken together, higenamine and related compounds can be developed as possible protective agents from oxidative cell injury or death.

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A study on Optimal Operation of Protection Coordination Devices Evaluation System in Distribution System with Distributed Sources (분산전원이 연계된 배전계통에 보호협조기기 평가시스템의 최적운용에 관한 연구)

  • Ji, Sungho;Song, Bangwoon;Kim, Byungki;Rho, Daeseok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.6
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    • pp.2971-2978
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    • 2013
  • Recently, with the world-wide issues about global warming and CO2 reduction, a number of distributed generations(DGs) such as photovoltaic(PV) and wind power(WP), are interconnected with the distribution systems. However, DGs can change the direction of the power flow from one-direction to bi-direction, and also change the direction and amount of fault current of existing distribution systems. Therefore, it may cause the critical problems on the power quality and protection coordination. This paper proposes an operation algorithm for bi-directional protection coordination using and apply it for the evaluation system for protection coordination. From the simulation results It is found that the proposed method is more effective and convenient than existing method.

A Study on the Reverse-Power-Flow Phenomenon due to Transformer Wiring Types in Distribution System (배전계통에서 변압기 결선에 의한 역 조류현상에 관한 연구)

  • Shin, Dong-Yeol;Ha, Bok-Nam;Jung, Won-Wook;Cha, Han-Ju
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.9
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    • pp.111-119
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    • 2008
  • As the penetration of distributed generation systems is recently high, there have been metering errors, trips of protective devices in KEPCO distribution systems including an occurrence of false fault-indicator in distribution automation system. The cause of malfunctions was the reverse-power-flow phenomenon due to transformer wiring types. By the effect of the reverse-power-flow, each of phase's fundamental currents was added by about 3 times on the neutral line. A new method based on the analysis of the reverse-power-flow is proposed in this paper. Fault currents on each section were analyzed by the proposed method, and the effect of types of transformer wiring was examined experimentally. In order to reduce the malfunctions due to the reverse-power-flow, controlling the zero-sequence impedance of transformer was designed and verified by using PSCAD/EMTDC software.

Lactoferrin Induces Tolerogenic Bone Marrow-Derived Dendritic Cells

  • Hui-Won Park;Sun-Hee Park;Hyeon-Ju Jo;Tae-Gyu Kim;Jeong Hyun Lee;Seung-Goo Kang;Young-Saeng Jang;Pyeung-Hyeun Kim
    • IMMUNE NETWORK
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    • v.20 no.5
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    • pp.38.1-38.12
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    • 2020
  • Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that initiate both T-cell responses and tolerance. Tolerogenic DCs (tDCs) are regulatory DCs that suppress immune responses through the induction of T-cell anergy and Tregs. Because lactoferrin (LF) was demonstrated to induce functional Tregs and has a protective effect against inflammatory bowel disease, we explored the tolerogenic effects of LF on mouse bone marrow-derived DCs (BMDCs). The expression of CD80/86 and MHC class II was diminished in LF-treated BMDCs (LF-BMDCs). LF facilitated BMDCs to suppress proliferation and elevate Foxp3+ induced Treg (iTreg) differentiation in ovalbumin-specific CD4+ T-cell culture. Foxp3 expression was further increased by blockade of the B7 molecule using CTLA4-Ig but was diminished by additional CD28 stimulation using anti-CD28 Ab. On the other hand, the levels of arginase-1 and indoleamine 2,3-dioxygenase-1 (known as key T-cell suppressive molecules) were increased in LF-BMDCs. Consistently, the suppressive activity of LF-BMDCs was partially restored by inhibitors of these molecules. Collectively, these results suggest that LF effectively causes DCs to be tolerogenic by both the suppression of T-cell proliferation and enhancement of iTreg differentiation. This tolerogenic effect of LF is due to the reduction of costimulatory molecules and enhancement of suppressive molecules.

Protective Effects of Sasa Borealis Leaves Extract on High Glucose-Induced Oxidative Stress in Human Umbilical Vein Endothelial Cells (혈관내피세포에서 고농도 포도당으로 유도된 산화스트레스에 대한 조릿대잎 추출물의 보호효과)

  • Hwang, Ji-Young;Han, Ji-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.12
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    • pp.1753-1760
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    • 2010
  • This study was designed to investigate the protective effects of Sasa borealis leaves on high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). Freeze-dried Sasa borealis leaves were extracted with 70% methanol and followed by a sequential fractionation with dicholoromethan, ethyl acetate, butanol and water. The ethyl acetate fraction from Sasa borealis leaves extract (ESLE) was used in this study because it possessed the strongest antioxidant activity among the various solvent fractions. Exposure of HUVECs to 30 mM high glucose for 48 hr resulted in a significant (p<0.05) decrease in cell viability, glutathion (GSH) concentration, activities of antioxidant enzymes including superoxide dimutase (SOD), glutathion peroxidase (GSH-px) and catalase, and a significant (p<0.05) increase in intracellular ROS and lipid peroxidation formation in comparison to the cells treated with 5.5 mM glucose. ESLE treatment decreased intracellular ROS and lipid peroxidation formation and increased cell viability, GSH concentration and expressions of SOD and catalase in HUVECs. These results suggest that ESLE may be able to protect HUVECs from high glucose-induced oxidative stress, partially through the antioxidative defense systems.

Antioxidative and Antiaging Effects of Sorbus commixta Twig Extracts (마가목 가지 추출물의 항산화 및 항노화에 관한 연구)

  • Lim, Gyu-Nam;Park, Min-A;Park, Soo-Nam
    • Journal of the Korean Applied Science and Technology
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    • v.28 no.4
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    • pp.482-490
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    • 2011
  • In this study, the antioxidative effects and inhibitory effects on tyrosinase and elastase of Sorbus commixta (S. commixta) twig extracts were investigated. The aglycone fraction of S. commixta twig extract showed the prominent free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity($FSC_{50}$, $13{\mu}g/mL$). Reactive oxygen species (ROS) scavenging activities of S. commixta twig extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated by the luminol-dependent chemiluminescence assay. The 50 % ethanol extract among extracts showed the most prominent ROS scavenging activity ($OSC_{50}$, $0.189{\mu}g/mL$). The cellular protective effects of extract/fractions of S. commixta twig on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The 50 % ethanol extract and ethyl acetate fraction showed the cellular protective effects against ROS in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). The inhibitory effect of S. commixta twig extract on tyrosinase was investigated to assess the whitening efficacy. The ethyl acetate ($IC_{50}$, $113.2{\mu}g/mL$) and aglycone fraction($IC_{50}$, $105.3{\mu}g/mL$) on tyrosinase showed more remarkable inhibitory effect than arbutin($IC_{50}$, $226.88{\mu}g/mL$), known as the whitening agent. The inhibitory effect of aglycone fraction ($IC_{50}$, $6.9{\mu}g/mL$) on elastase was simillar to quercetin($IC_{50}$, $6.1{\mu}g/mL$), flavonoid known as reference compound. These results indicate that extract/fractions of S. commixta twig can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. S. commixta twig extracts can be applicable to new functional cosmetics for anti-aging products.

Resveratrol Upregulates p21, Cell Cycle Regulator, in Gaucher Disease Cells (Gaucher병에서 resveratrol의 세포주기 조절자 p21을 통한 세포보호 효과 연구)

  • Kim, Dong-Hyun;Heo, Tae-Hwe;Kim, June-Bum;Kim, Sung-Jo
    • Journal of Life Science
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    • v.20 no.8
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    • pp.1281-1286
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    • 2010
  • Gaucher disease (GD) is caused by glucocerebrosidase functional deficiency and the most prevalent lysosomal storage disorder (LSD), with an incidence of about 1 in 20,000 new births. Resveratrol, one kind of phytoalexin, is a produced naturally by several plants and has anti-tumor, anti-aging, anti-inflammatory and neuro-protective effects. In this paper we provide the cellular protective effect of resveratrol in both type I and type II Gaucher disease cells. Resveratrol treatment did not show any significant change in the p21 and p53 mRNA expression level, however expression level of the p21 protein, a cell cycle arrest factor, shows significant increment in both types of Gaucher disease cells. These cell cycle arrest patterns were confirmed by both MTT assay measurement and microscopy detection. In comparison, expression level of poly ADP ribose polymerase (PARP), an apoptosis indicator protein, was significantly decreased in both type I and II Gaucher disease cells after treatment with resveratrol. This result indicates that resveratrol relievescellular apoptotic stress fromtype I and II Gaucher disease cells. Therefore, we demonstrate that resveratrol inhibits cell proliferation via p21 activity and activates cellular repair systems for Gaucher disease cells. Our results provide at least one of the molecular mechanisms of Gaucher disease and may allow the verification of potential drug targets for therapeutic trials.

Protective effect of Ganopoly and Ganopoly/C+ on nephrotoxicity induced by cisplatin in rats (Cisplatin의 신장독성에 대한 영지추출물 복합제제의 보호효과)

  • Kim Dae Geun;Kim Kun Jung;Ju Sung Min;Kim Yong Ik;Choi Ho Seung;Keum Kyung Soo;Kim Won Sin;Gao Yiu Ai;Jeon Byung Hun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.316-325
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    • 2003
  • In this paper, the effect of Ganopoly(extracts of Ganoderma lucidum) and Ganopoly/C+(70% Ganopoly + 30% chitosan) on cisplastin-induced nephrotoxicity was investigated in Sprague-Dawley rats. A single dose of cisplastin(5 ㎎/㎏) kg) was administered intraperitoneally after pretreatment of saline, Ganopoly and Ganopoly/C+ for 7 days. The nephrotoxicity and renal function were manifestated by the changes of body weight, blood pressure, biochemical changes and solute in urine and plasma. After the treatment of CDDP(cis-dichlorodiamineplatinum), a significant elevation of kidney weight, serum urea, cretinine, urine volume for 24 hours, urine magnesium, and a severe or significant decrease in body weight, blood pressure, creatinine clearance, urine osmolarity, serum albumin, etc. The nephrotoxicity was further confirmed by a significant decrease in glutathione S-transferase(GSH) in urine and kidney homogenate, GSH, glutathione peroxidase(GSH-Px) and catalase in kidney tissue. And also the lipid peroxidation was significantly increased in kidney homogenate. These signs of nephrotoxicity was ameliorated by the pretreatment and consecutive administration of Ganopoly and Ganopoly/C+ for 14 days after the Lp. injection of CDDP on 7th day after pretreatment of Ganopoly and Ganopoly/C+. The amelioration of nephrotoxicity was evidenced by significant reduction in serum urea and creatinine concentration, and improvement of other index of renal function. And The activity of antioxidant enzymes were partially recovered in kidney tissue of rats treated by CDDP and the administration of Ganopoly and Ganopoly/C+. These results indicate the cispastin induced nephrotoxicity is due to an impairment of tubular reabsorption systems enhanced by necrosis of proximal tubule, and the Ganopoly and Ganopoly/C+ has a partial protective effect on nephrotoxicity induced by CDDP. The polysacchride of Ganoderma lucidum may improve the therapeutic index of nephrotoxicity induced by CDDP. However, it is needed to elucidate the mechanism for confirming the therapeutic effect.