• Title/Summary/Keyword: Protective systems

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Protective Effects of a Herbal Composition (HemoHIM) Against Apoptosis Induced by Oxidative Stress of Hydrogen Peroxide (과산화수소의 산화적 스트레스로 유도된 Apoptosis에 대한 생약복합조성물(HemoHIM)의 방호효과 평가)

  • Shin, Sung-Hae;Kim, Do-Soon;Kim, Mi-Jung;Kim, Sung-Ho;Jo, Sung-Kee;Byun, Mung-Woo;Yee, Sung-Tae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.9
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    • pp.1127-1132
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    • 2006
  • In our previous study, a novel herb mixture (HIM-I) of Angelica gigas radix, Cnidium officinale rhizoma, and Paeonia japonica radix was developed to protect the intestinal and immune systems and promote its recovery against radiation damage. A new herbal composition (HemoHIM) with the high immune modulating activity was developed from HIM-I. HIM-I was fractionated into ethanol fraction (HIM-I-E) and polysaccharide fraction (HIM-I-P). And HemoHIM was prepared by adding HIM-I-P to HIM-I. HemoHIM showed more effective than HIM-I in immune modulation as well as radioprotection. The present study is designed to investigate the protective effects of HIM-I, HIM-I-P, and HemoHIM on hydrogen peroxide $(H_2O_2)$ induced apoptosis of human promyelocytic leukemia (HL-60) cells. It was shown that $H_2O_2$ treatment reduced the viability of cells, and increased appearance of DNA ladders, hypodiploid (subG1) cells, and phosphatidylserine translocation level. Pretreatment of HemoHIM significantly reduced the cytotoxic effect induced by $H_2O_2$, associated with reducing the translocation of phosphatidylserine, hypodiploid cells and DNA ladders. HemoHIM appeared to be more protective than HIM-I against $H_2O_2$ induced apoptosis whereas, it exhibited similar activity to HIM-I-P. These results indicated that HemoHIM might be an useful agent for protection against oxidative stress $(H_2O_2)-induced$ apoptosis as well as immune modulation, especially since it is a relatively nontoxic natural product.

Experimental and analytical investigation of steel beams rehabilitated using GFRP sheets

  • El Damatty, A.A.;Abushagur, M.;Youssef, M.A.
    • Steel and Composite Structures
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    • v.3 no.6
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    • pp.421-438
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    • 2003
  • Aging and deterioration of existing steel structures necessitate the development of simple and efficient rehabilitation techniques. The current study investigates a methodology to enhance the flexural capacity of steel beams by bonding Glass Fibre Reinforced Plastic (GFRP) sheets to their flanges. A heavy duty adhesive, tested in a previous study is used to bond the steel and the GFRP sheet. In addition to its ease of application, the GFRP sheet provides a protective layer that prevents future corrosion of the steel section. The study reports the results of bending tests conducted on a W-shaped steel beam before and after rehabilitation using GFRP sheets. Enhancement in the moment capacity of the beam due to bonding GFRP sheet is determined from the test results. A closed form analytical model that can predict the yield moment as well as the stresses induced in the adhesive and the GFRP sheets of rehabilitated steel beam is developed. A detailed finite element analysis for the tested specimens is also conducted in this paper. The steel web and flanges as well as the GFRP sheets are simulated using three-dimensional brick elements. The shear and peel stiffness of the adhesive are modeled as equivalent linear spring systems. The analytical and experimental results indicate that a significant enhancement in the ultimate capacity of the steel beam is achieved using the proposed technique. The finite element analysis is employed to describe in detail the profile of stresses and strains that develop in the rehabilitated steel beam.

Effects of Dietary Proteins and Inositol Hexaphosphate on the Preneoplastic Lesions and Antioxidant Enzymes of Hepatocellular Carcinogenesis in Rats (식이 단백질의 종류 및 Inositol Hexaphosphate가 간세포 암화과정에서 전암성 병변의 지표 및 항산화 효소계에 미치는 영향)

  • 김현덕;최혜미
    • Korean Journal of Community Nutrition
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    • v.4 no.2
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    • pp.239-247
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    • 1999
  • Six-week-old Sprague Dawley rats were fed the diets of 20% casein or soy protein. Two weeks after the feeding, hepatocellular chemical carcinogenesis was initiated by diethylnitrosamine(DEN), and promoted by the diet containing 0.01% 2-acetylamino-fluorene(AAF) and two-thirds partial hepatectomy(PH). The animals were sacrificed at 8 weeks after the DEN injection. The area of placetal glutathione S-trnasferase(GST-P) positive foci, the activities of several enzymes in cellualr antioxidant enzyme systems and glucose 6-phosphatase were determined to investigate the mechanism of the anticarcinogenic effect by the dietary proteins. In another set of experiments, the drinking water of rats fed casein was supplemented with 1.5% inositol hexaphosphate(InsP6) to elucidate whether it has the comparable anticancer action of soy protein. The area and number of GST-P positive foci in the soy protein group were significantly(p<0.05) lower than those inthe casein group. The livers of rats fed casein showed moderate fattydegeneration and larger hyperplastic nodules than those of rats fed soy protein. In another set of experiments, the area and number of GST-P positive foci in the rats fed casein supplemented with InsP6 were not significantly different from those in the rats fed casein or soy protein. The lipid peroxidation of rats fed different protein sources showed no significant difference. Glutathione S-transferase(GST) activities were increased significantly(p<0.05) by carcinogen treatment in all dietary groups. Glucose 6-phosphatase(G6Pase) activities were decreased by carcinogen treatment, and hence showed a reverse relationship(r=-0.695, p<0.01) to the GST-P positive foci. Therefore, the activities in the rats fed casein were lower than those in the rats fed soy protein. These results suggest that the soy protein seems to be more anti-carcinogenic than casein by decreasing the preneoplastic lesion and by increasing the membrane stability but inositol hexaphosphate, a component of soy protein, may not be protective against hepatocarcinogenesis.

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Enhancing Identity Privacy Using Identity-Based Encryption in Access Networks of 3GPP (3GPP 접속 망에서 ID 기반 암호를 이용한 신원 프라이버시 개선 연구)

  • Jung, Yonghyun;Lee, Dong Hoon
    • KIPS Transactions on Computer and Communication Systems
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    • v.5 no.10
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    • pp.361-372
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    • 2016
  • Identity Privacy issues such as exposures of IMSIs(International Mobile Subscriber Identities) in access network have been consistently raised throughout GSM, UMTS, LTE in 3GPP. The 3GPP specification uses temporary identities instead of IMSI to ensure anonymity of the user. Even if temporary identities are disclosed, Identity Privacy may be maintained at a safe level by security policies such as no linkability and periodic update. But in case of IMSI, it cannot be changed even though it is exposed. There still exist some situations that IMSI is used in clear text for the authentication. Therefore, a protective mechanism for the identity confidentiality is needed. In this paper we propose a protocol based on IBE(Identity-based Encryption) to protect permanent identities in access network. By simplifying the scheme, this protocol has minimized the system impact on current 3GPP environment. And this scheme can be applied to all kind of permanent identities and 3GPP AKA(Authentication and Key Agreement) protocols in access network.

The Effect of Erythropoietin on Ischemia-Reperfusion Injury: An Experimental Study in Rat TRAM Flap Model (백서 복직근판의 허혈-재관류 손상에 대한 Erythropoietin의 영향)

  • Kim, Eun Key;Hong, Joon Pio
    • Archives of Plastic Surgery
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    • v.33 no.5
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    • pp.621-626
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    • 2006
  • Purpose: Erythropoietin is traditionally known to regulate erythropoiesis, but recently its protective effect against ischemia-reperfusion injury has been studied mainly in cardiovascular and neuronal systems. This study was planned to investigate the effects of recombinant human erythropoietin on ischemia-reperfusion injury in rat TRAM flap model. Methods: Superiorly based TRAM flap was elevated and ischemic insult was given for four hours. Thirty minutes before reperfusion, single dose recombinant human Erythropoietin(5000IU/kg) was injected via intraperitoneal route in the treatment group. At 24 hours postoperatively, systemic neutrophil count, tissue myeloperoxidase activity, malonyldialdehyde amount, nitric oxide content, tissue water content and histologic finding of inflammation was evaluated. On 10 days postoperatively, flap survival rate, angiogenesis and change in hematocrit level was evaluated. Results: Tissue nitric oxide level was significantly higher and myeloperoxidase activity was significantly lower in the treatment group 24 hours after reperfusion. Tissue water content was significantly lower in the treatment group. Perivascular neutrophil infiltration and intravascular adhesion was marked in the control group. Mean flap survival after ten days was 69% in the treatment group, and 47% in the control group, demonstrating a significant difference. Neovascularization in the treatment group also outnumbered the control group. No significant hematocrit rise was noted ten days after erythropoietin administration. Conclusion: Recombinant human Erythropoietin improved flap survival in ischemia-reperfusion injured rat TRAM flaps, at least partially owing to suppressed inflammation, increased nitric oxide, and enhanced angiogenesis.

Stability Evaluation of Series and Parallel Varistor Combination Using Thermal Image Analysis (열화상 분석을 통한 바리스터의 직렬과 병렬 조합의 안전성 평가)

  • Eom, Ju-Hong;Cho, Sung-Chul;Lee, Tae-Hyung;Han, Hoo-Sek
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.8
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    • pp.22-29
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    • 2006
  • According to the recent revision of KS on the basis of the IEC, equipotential grounding systems has been come into focus and the use of surge protective devices(SPD) has been increased radically in order to operate the power system stably. $Z_nO$ varistor with non-linear resistance, which has an outstanding voltage-current(V-I) characteristic, is mainly used in power system to limit surge voltage and divert surge current. $Z_nO$ varistors are packaged several types based on the circuit assembly to be connected to a.c. power line. When the user assemble the $Z_nO$ varistors into parallel or series circuit package, there are my things to be taken into consideration including functions and thermal stability because they are directly related to the safety. We compare stabilities of each assembly type by measuring residual voltage, discharge current, leakage current and surface temperature concerned to the protection performances between a single device with a 40[kA] of current capacity and parallel or series circuits type of varistor package.

Radioprotective Effects of Sun Ginseng on Hematogenic and Immune Systems and Liver Toxicities in Mice Exposed to Medium Dose of Irradiation (선삼 투여가 중선량 X-선을 조사한 마우스에서 조혈면역계 및 간장 독성에 미치는 방호효과)

  • Sin, Jung-Sub;Kim, Young-Chul
    • Environmental Analysis Health and Toxicology
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    • v.22 no.2 s.57
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    • pp.147-156
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    • 2007
  • Six week-old ICR mice were divided into four groups including NC, RC, RR and RS, then they were injected with sun ginseng (RS), red ginseng (RR) and saline (RC) intraperitoneally as an amount of 60mg/kg body weight at 1 hour, 12 hours and 36 hours before the whole body irradiation with 6.5Gy of X-ray. And the mice were sacrificed at nine days after the irradiation. The RS group were significant increase in the weight of spleen (p<0.05) and the numbers of endogenous spleen colony (p<0.001) and WBC (p<0.05) especially neutrophils, lymphocytes and monocytes in comparison with the RC group. The RR group were significant increase in the numbers of endogenous spleen colony (p<0.01) and WBC (p<0.05) especially neutrophils, lymphocytes and eosinophils in comparison with the RC group. The RS group exhibited a more increase in the weight of spleen and the number of endogenous spleen colony than the RR group. The values of ALT (alanine transaminase) and AST (aspartate transaminase) were significantly elevated (p<0.05) by radiation and they were significantly decreased (p<0.05) in the RS group to the values of the NC group. The value of TBARS(thiobarbituric acid reactive substance) was significantly elevated (p<0.01) by radiation and it was significantly decreased (p<0.05) in the RS group. And the values of SOD (superoxide dismutase) and CAT (catalase) were significantly increased (p<0.05) in the RS group in comparison with the RC group. Taken together the above results, sun ginseng demonstrated the protective effects on hepatocytes and immune and hematopoietic cells in mice exposed to medium dose of irradiation, and those radioprotective effects were a little higher or similar to the red ginseng.

Biological effects of zinc oxide nanoparticles on inflammation

  • Kim, Min-Ho
    • CELLMED
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    • v.6 no.4
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    • pp.23.1-23.6
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    • 2016
  • With the rapid developments in nanotechnology, an increasing number of nanomaterials have been applied in various aspects of our lives. Recently, pharmaceutical nanotechnology with numerous advantages has growingly attracted the attention of many researchers. Zinc oxide nanoparticles (ZnO-NPs) are nanomaterials that are widely used in many fields including diagnostics, therapeutics, drug-delivery systems, electronics, cosmetics, sunscreens, coatings, ceramic products, paints, and food additives, due to their magnetic, catalytic, semiconducting, anti-cancer, anti-bacterial, anti-inflammatory, ultraviolet-protective, and binding properties. The present review focused on the recent research works concerning role of ZnO-NP on inflammation. Several studies have reported that ZnO-NP induces inflammatory reaction through the generation of reactive oxygen species by oxidative stress and production of inflammatory cytokines by activation of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$). Meanwhile, other researchers reported that ZnO-NP exhibits an anti-inflammatory effect by inhibiting the up-regulation of inflammatory cytokines and the activation of $NF-{\kappa}B$, caspase-1, $I{\kappa}B$ $kinase{\beta}$, receptor interacting protein2, and extracellular signal-regulated kinase. Previous studies reported that size and shape of nanoparticles, surfactants used for nanoparticles protection, medium, and experimental conditions can also affect cellular signal pathway. This review indicated that the anti-inflammatory effectiveness of ZnO-NP was determined by the nanoparticle size as well as various experimental conditions. Therefore, the author suggests that pharmaceutical therapy with the ZnO-NP is one of the possible strategies to overcome the inflammatory reactions. However, further studies should be performed to maximize the anti-inflammatory effect of ZnO-NP to apply as a potential agent in biomedical applications.

Protective Effect of Oenanthe javanica Extract on Acetaminophen-induced Hepatotoxicity in Rats (Acetaminophen으로 유도한 쥐의 간 독성에 대한 미나리(Oenanthe javanica) 추출액의 간 보호 작용)

  • Park, Jong-Cheol;Kim, Jong-Yeon;Lee, Youn-Ju;Lee, Ji-Seon;Kim, Bo-Geum;Lee, Seung-Ho;Nam, Doo-Hyun
    • YAKHAK HOEJI
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    • v.52 no.4
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    • pp.316-321
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    • 2008
  • The hepatoprotection by the methanol extract of Oenanthe javanica DC (water dropwort) (OJME) was investigated in Sprague Dawley rats with inducing liver damage by acetaminophen. After OJME administration for 1 week, the increase of hepatic lipid peroxide level by acetaminophen-induced hepatotoxicity was significantly reduced. In case of phase I microsomal enzyme systems including cytochrome P-450, aminopyrine N-demethylase and aniline hydroxylase, any significant differences between in control and in OJME-pretreated group was observed after acetaminophen treatment. However, the pretreatment of OJME maintained the hepatic glutathione level and the activity of liver cytosolic glutathione S-transferase, which was significantly decreased by the acetaminophen intoxication. Among the glutathione-generating system, glutathione reductase was more responsible for its biosynthesis rather than ${\gamma}-glutamylcystein$ synthetase. OJME itself showed the strong inhibition activity on DPPH radical generation. In conclusion, OJME administration maintains the liver glutathione pool and hepatic glutathione S-transferase activity, in addition with its high anti-oxidative capability, to show hepatoprotective effect from acetaminophen intoxication.

Scavenging Activity of Reactive Oxygen Species and Inhibitory Effect of Cytochrome P450 from Circium japonicum Extract (대계 추출물의 할성산소 소거능 및 Cytochrome P450 효소 저해효과)

  • Kim, Hyuck;Yi, Hyo-Seung;Park, Won-Hwan;Moon, Jin-Young
    • The Korea Journal of Herbology
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    • v.22 no.1
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    • pp.53-61
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    • 2007
  • Objectives: Our previous studies have clearly demonstrated that the scavenging activity of reactive oxygen species (ROS), protective effect of lipid peroxidation (LPO), and inhibition of cytochrome P450 isozymes (CYPs) from the Circium japonicum aqua-acupuncture solution (CJAS). But, Circium japonicum water extracted solution (CJWS) was weakly reported in cardiovascular diseases such as oxidative stress-mediated atherosclerosis or its value evaluated. Methods: CJWS was assessed to determine the mechanism of its scavenging activity of ROS and inhibitory effect of CYP 2E1. Results: CJWS exhibited a concentration-dependent scavenger of DPPH and superoxide anions radicals using different assay systems. In addition, CJWS showed dose-dependent free radical scavenging activity, including hydroxyl radicals, peroxynitrite, and nitric oxide. The CJWS was also found to be effective in protecting rat liver homogenate against LPO. Futhermore, the CJWS showed significant inhibition of CYP 2E1 induced by pyrazol in a rat liver microsome. Conclusion : ROS and CYPs may play a role in several diseases, such as cardiovascular disease and heart failure. Our study demonstrated that the CJWS has excellent scavenging activity of ROS. Hence, it is worthwhile to investigate the potential effectiveness of CJWS in preventing oxidative stress-mediated cardiovascular diseases.

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