• Title/Summary/Keyword: Damage Tolerance

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Protective Effect of Nitric Oxide against Oxidative Stress under UV-B Radiation in Maize Leaves (UV-B 조사시 옥수수 잎의 산화적 스트레스에 대한 Nitric Oxide의 보호효과)

  • Kim, Tae-Yun;Jo, Myung-Hwan;Hong, Jung-Hee
    • Journal of Environmental Science International
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    • v.19 no.12
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    • pp.1323-1334
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    • 2010
  • The effect of nitric oxide (NO) on antioxidant system and protective mechanism against oxidative stress under UV-B radiation was investigated in leaves of maize (Zea mays L.) seedlings during 3 days growth period. UV-B irradiation caused a decrease of leaf biomass including leaf length, width and weight during growth. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated UV-B stress induced growth suppression. NO donor permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under UV-B stress, suggesting that NO has protective effect on chloroplast membrane in maize leaves. Flavonoids and anthocyanin, UV-B absorbing compounds, were significantly accumulated in the maize leaves upon UV-B exposure. Moreover, the increase of these compounds was intensified in the NO treated seedlings. UV-B treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in maize leaves, while NO donor prevented UV-B induced increase in the contents of malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that NO serves as antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, catalase (CAT) and ascorbate peroxidase (APX) in maize leaves in the presence of NO donor under UV-B stress were higher than those under UV-B stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3- oxide (PTIO), a specific NO scavenger, to the maize leaves arrested NO donor mediated protective effect on leaf growth, photosynthetic pigment and free radical scavenging activity. However, PTIO had little effect on maize leaves under UV-B stress compared with that of UV-B stress alone. $N^{\omega}$-nitro-L-arginine (LNNA), an inhibitor of nitric oxide synthase (NOS), significantly increased $H_2O_2$ and MDA accumulation and decreased antioxidant enzyme activities in maize leaves under UV-B stress. This demonstrates that NOS inhibitor LNNA has opposite effects on oxidative resistance. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative stress induced by UV-B radiation and thus confer UV-B tolerance.

Working Mechanism of Peroxiredoxins (Prxs) and Sulphiredoxin1 (Srx1) in Arabidopsis thaliana (애기장대 peroxiredoxins (Prxs)과 sulphiredoxin1 (Srx1)의 작용기작)

  • Kim, Min-Gab;Su'udi, Mukhamad;Park, Sang-Ryeol;Hwang, Duk-Ju;Bae, Shin-Chul
    • Journal of Life Science
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    • v.20 no.12
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    • pp.1777-1783
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    • 2010
  • Plants generate reactive oxygen species (ROS) as a by-product of normal aerobic metabolism or when exposed to a variety of stress conditions, which can cause widespread damage to biological macromolecules. To protect themselves from oxidative stress, plant cells are equipped with a wide range of antioxidant proteins. However, the detailed reaction mechanisms of these are still unknown. Peroxiredoxins (Prxs) are ubiquitous thiol-containing antioxidants that reduce hydrogen peroxide with an N-terminal cysteine. The active-site cysteine of peroxiredoxins is selectively oxidized to cysteine sulfinic acid during catalysis, which leads to inactivation of peroxidase activity. This oxidation was thought to be irreversible. Recently identified small protein sulphiredoxin (Srx1), which is conserved in higher eukaryotes, reduces cysteine.sulphinic acid in yeast peroxiredoxin. Srx1 is highly induced by $H_2O_2$-treatment and the deletion of its gene causes decreased yeast tolerance to $H_2O_2$, which suggest its involvement in the metabolism of oxidants. Moreover, Srx1 is required for heat shock and oxidative stress induced functional, as well as conformational switch of yeast cytosolic peroxiredoxins. This change enhances protein stability and peroxidase activity, indicating that Srx1 plays a crucial role in peroxiredoxin stability and its regulation mechanism. Thus, the understanding of the molecular basis of Srx1 and its regulation is critical for revealing the mechanism of peroxiredoxin action. We postulate here that Srx1 is involved in dealing with oxidative stress via controlling peroxiredoxin recycling in Arabidopsis. This review article thus will be describing the functions of Prxs and Srx in Arabidopsis thaliana. There will be a special focus on the possible role of Srx1 in interacting with and reducing hyperoxidized Cys-sulphenic acid of Prxs.

Effects of compound organic acid calcium on growth performance, hepatic antioxidation and intestinal barrier of male broilers under heat stress

  • He, Junna;Ma, Lianxiang;Qiu, Jialing;Lu, Xintao;Hou, Chuanchuan;Liu, Bing;Yu, Dongyou
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.7
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    • pp.1156-1166
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    • 2020
  • Objective: The aim of this study was to evaluate the effects of compound organic acid calcium (COAC) on growth performance, hepatic antioxidant status and intestinal barrier of male broilers under high ambient temperature (32.7℃). Methods: Nine hundred healthy one-d-old Cobb-500 male broiler chicks were randomly assigned into three groups with six replicates of 50 birds each. A basal diet supplemented with 0% (control), 0.4% and 0.8% COAC, respectively were fed to birds for 6 weeks. All treatments were under high ambient indoor temperature of 32.7℃, and had a constant calcium and available phosphorus ratio. Results: The results showed that, compared with control, the average daily gain of broilers in 0.4% and 0.8% was significantly increased and the ratio of feed to gain in in 0.4% and 0.8% was significantly decreased at 1 to 21, 22 to 42 and 1 to 42 days of age (p<0.05). Compared with control, 0.8% COAC slightly decreased (p = 0.093) the content of malondialdehyde in liver at 42 days of age while 0.4% COAC significantly decreased (p<0.05) the activity of alkaline phosphatase. Furthermore, 0.4% COAC significantly enhanced the intestinal barrier function via increasing jejunal and ileal ocln transcription, promoting jejunal mucin 2 transcription at 42 days of age (p<0.05), and decreasing jejunal toll-like receptor 2 (TLR-2) and ileal TLR-15, inducible nitric oxide synthase compared with control group (p<0.05). Whereas, no significant differences on the transcription of interleukin-1β in jejunum and ileum were observed among three treatments (p>0.05). Overall, heat stress caused by high natural environment temperature may induce the damage to hepatic antioxidation and intestinal barrier. Conclusion: Dietary inclusion of COAC can improve the tolerance of broilers to thermal environment through the modification of antioxidative parameters in liver and the mRNA expression of genes in intestinal barrier, resulting in an optimal inclusion level of 0.4%.

Antioxidant Enzyme Activity and Cell Membrane Stability of Korean Bermudagrass Genotypes Different in Ploidy at Dormant Stage (배수성이 다른 자생 버뮤다그래스의 휴면 전후 항산화 효소활성 및 세포막 안정성 변화)

  • Lee, Geung-Joo;Lee, Hye-Jung;Ma, Ki-Yoon;Jeon, Young-Ju;Kim, In-Kyung
    • Asian Journal of Turfgrass Science
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    • v.25 no.1
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    • pp.17-21
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    • 2011
  • Korean bennudagrass collections showed diverse genetic variations in their morphology, growth habit, and cytological aspects. Chromosome number and nuclear DNA content of the bennudagrasses indicated a ploidy level ranging from triploid (2n=3x) to hexaploid (2n=6x). In this study, we investigated the different responses of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, ascorbate peroxidase) and cell membrane stability of those bennudagrass cytotypes to lower temperature and shorter day length, which meets a dormant induction in Korea. All the antioxidant enzymes were found to be higher during dormant stage, while the heme-containing catalase which converts hydrogen peroxide ($H_2O_2$) to water and oxygen molecules was activated before dormant initiation in the three cytotypes except for hexaploid bennudagrass. The triploid and tetraploid which exhibited relatively finer leaves and a rapid establishment speed were found to show increased activities of superoxide dismutase and peroxidase enzyme. The malondialdehyde(MDA) which is a product of lipid peroxidation in the cell membrane damaged by the hydroxyl radical was increased in all cytotypes as temperature declined, and tri- and tetraploids which had more protective antioxidant enzymes demonstrated a significantly lower MDA production. Similarly electrolyte leakage was higher in penta- and hexaploidy, seemingly more damage to cell membrane when low temperature was implemented. Results indicated that antioxidant responses of different cytotypes were genetically specific, which needs to be investigated the relevance with the low temperature tolerance in the bermudagrass further at the molecular level.

The Site-Directed A184S Mutation in the HTH Domain of the Global Regulator IrrE Enhances Deinococcus radiodurans R1 Tolerance to UV Radiation and MMC Shock

  • Zhang, Chen;Zhou, Zhengfu;Zhang, Wei;Chen, Zhen;Song, Yuan;Lu, Wei;Lin, Min;Chen, Ming
    • Journal of Microbiology and Biotechnology
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    • v.25 no.12
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    • pp.2125-2134
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    • 2015
  • IrrE is a highly conserved global regulator in the Deinococcus genus and contributes to survival from high doses of UV radiation, ionizing radiation, and desiccation. Drad-IrrE and Dgob-IrrE from Deinococcus radiodurans and Deinococcus gobiensis I-0 each share 66% sequence identity. However, Dgob-IrrE showed a stronger protection phenotype against UV radiation than Drad-IrrE in the D. radiodurans irrE-deletion mutant (ΔirrE), which may be due to amino acid residues differences around the DNA-binding HTH domain. Site-directed mutagenesis was used to generate a Drad-IrrE A184S single mutant, which has been characterized and compared with the ΔirrE mutant complemented strain with Drad-irrE, designated ΔirrE-E. The effects of the A184S mutation following UV radiation and mitomycin C (MMC) shock were determined. The A184S mutant displayed significantly increased resistance to UV radiation and MMC shock. The corresponding A184 site in Dgob-IrrE was inversely mutated, generating the S131A mutant, which exhibited a loss of resistance against UV radiation, MMC shock, and desiccation. qPCR analysis revealed that critical genes in the DNA repair system, such as recA, pprA, uvrA, and ddrB, were remarkably induced after UV radiation and MMC shock in the ΔirrE-IE and A184S mutants. These data suggested that A184S improves the ability against UV radiation and MMC shock, providing new insights into the modification of IrrE. We speculated that the serine residue may determine the efficiency of DNA binding, leading to the increased expression of IrrE-dependent genes important for protection against DNA damage.

A Development of 3D Modeling-based Survivability Analysis System for Armored Fighting Vehicle using Importance of Components (부품의 중요도를 활용한 3차원 전차 모델 기반 생존성 분석 시스템 개발)

  • Hwang, Hun-Gyu;Lee, Jae-Wook;Lee, Jae-Woong;Lee, Jang-Se
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.5
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    • pp.1269-1276
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    • 2015
  • The mission capability of tank depends on its survivability. The survivability is ability for protection and tolerance by damage from threats. To improve the survivability of tank, we need an effectiveness analysis for loss of components, and accomplish performance enhancement using the result of analysis. In this paper, we develop a survivability analysis system for tank based on the importance. The importance numerically represents weight of each component which consisting of whole tank, also the importance is basic method of quantitative survivability analysis. To do this, we assign weight values to each component of tank, compose a weight tree, apply the importance calculation equation, and analyze the survivability of tank. Also we develop the system that consists of component structuralization and weight value setting program and survivability analysis and visualization program, and evaluate the system using implemented 3D CAD models of components of tank. The developed system apply to arrangement components.

Amelioration Effects of Irrigation-Aspiration on Renal Ischemia-Reperfusion Injury in Canine Model (개에서 신장의 허혈-재관류 손상에 대한관류-흡인의 감소효과)

  • Lee, Jae-Il;Son, Hwa-Young;Jeong, Seong-Mok;Kim, Myung-Cheol
    • Journal of Veterinary Clinics
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    • v.25 no.4
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    • pp.257-262
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    • 2008
  • Renal ischemia-reperfusion injury is great clinical important because viability of the transplanted organ depends on the tolerance of the graft to ischemia-reperfusion injury, an inevitable processing during surgery. The purpose of this study was to investigate the effects of irrigation-aspiration in ischemia-reperfusion injury model induced by cross-clamping of renal vessels. Blood samples were collected from these dogs for measurement of kidney function and antioxidant enzyme activity, and RI at the intrarenal artery was measured at different time intervals. And the kidneys were taken for histopathologic evaluation at day 14. Kidney function (Cr and BUN) showed a significant increasing in untreated group compared to treated group. Resistive index of intrarenal artery was no significant difference among the groups. Activity of antioxidant enzymes in plasma was significant decrease in untreated group compare to control group while in treated group was no significant difference compared to control group. In histopathologic finding, treated group was showed less damage than that of untreated group. This result suggests that the processing of irrigation-aspiration is useful to reducing ischemia-reperfusion injury.

The characterization of transgenic Chrysanthemum under low temperature condition (저온저항성 유전자가 도입된 국화 형질전환체 특성)

  • Choi, In-Young;Han, Soo-Gon;Kang, Chan-Ho;Song, Young-Ju;Lee, Wang-Hyu
    • Journal of Plant Biotechnology
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    • v.35 no.1
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    • pp.55-61
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    • 2008
  • Previous studies on genetic transformation of chrysanthemum using cold regulated gene (BN115) have been conducted and the PCR and Real-Time PCR based method to determine the presence of the transferred cold regulated gene in the chrysanthemum was established. To check whether over-expression of BN115 gene in transgenic chrysanthemum will enhance their tolerance to cold stress, the transgenic chrysanthemum were grown under low temperature condition and several cold signalling including growth characteristics, stoma size and shape, SPAD value and ion leakage test were investigated. The transgenic chrysanthemum in the low temperature growth chamber grow much faster in term of the height, number and size of the leaves than those of wild-type plants and damage of transgenic plant caused by the low temperature was much less than that of wild-type plants. The stoma type and size of transgenic plant leaves grown at $5^{\circ}C$ were much similar to of wild-type plant cultured on $25^{\circ}C$ It has been found that SPAD value of transgenic plants was much higher than those of wild-type, but the EC density being lower under low temperature condition.

Effective Heat Treatment Techniques for Control of Mung Bean Sprout Rot, Incorporable into Commercial Mass Production

  • Lee, Jung-Han;Han, Ki-Soo;Kim, Tae-Hyoung;Bae, Dong-Won;Kim, Dong-Kil;Kang, Jin-Ho;Kim, Hee-Kyu
    • The Plant Pathology Journal
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    • v.23 no.3
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    • pp.174-179
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    • 2007
  • Seedlot disinfection techniques to control mung bean sprout rot caused by Colletoricum acutatum and C. gloeosporioides were evaluated for commercial production scheme. Soaking seedlots in propolis (100 X) and ethanol (20% for 30 min) appeared promising with control values of 85.5 and 80.8 respectively, but still resulted in up to 20% rot incidence. None of the C. acutatum conidia survived through hot water immersion treatment (HWT) for 10 min at temperatures of 55, 60 and $65^{\circ}C$, whereas the effective range of the dry heat treatment (DHT) was $60-65^{\circ}C$. Tolerance of mung bean seedlot, as estimated by hypocotyl elongation and root growth, was lower for HWT than for DHT. Germination and growth of sprouts were excellent over the range of $55-65^{\circ}C\;at\;5^{\circ}C$ intervals, except for HWT at $65^{\circ}C$ for 5 min. At this marginal condition, heat damage appeared so that approximately 2% of seeds failed to sprout to normal germling and retarded sprouts were less than 5% with coarse wrinkled hypocotyls. These results suggested that DHT would be more feasible to disinfect mung bean seedlots for commercial sprout production. Heat treatment at above ranges was highly effective in eliminating the epiphytic bacterial strains associated with marketed sprout rot samples. HWT of seedlot at 55 and $60^{\circ}C$ for 5 min resulted in successful control of mung bean sprout rot incidence with marketable sprout quality. DHT at 60 and $65^{\circ}C$ for 30 min also gave good results through the small-scale sprouting system. Therefore, we optimized DHT scheme at 60 and $65^{\circ}C$ for 30 min, considering the practical value of seedlot disinfection with high precision and accuracy. This was further proved to be a feasible and reliable method against anthracnose incidence and those bacterial strains associated with marketed sprout rot samples as well, through factory scale mung bean sprout production system.

Information Hiding Technique in Smart Phone for the Implementation of GIS Web-Map Service (GIS 웹 맵 서비스 구현을 위한 스마트 폰에서의 정보은닉 기법)

  • Kim, Jin-Ho;Seo, Yong-Su;Kwon, Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.13 no.5
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    • pp.710-721
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    • 2010
  • Recently, for the advancement of embedded technology about mobile device, a new kind of service, mash-up is appeared. It is service or application combining multimedia content making tool or device and web-GIS(geographic information system) service in the mobile environment. This service can be ease to use for casual user and can apply in various ways. So, It is served in web 2.0 environment actively. But, in the mashup service, because generated multimedia contents linked with web map are new type of multimedia contents which include user's migration routes in the space such as GPS coordinates. Thus, there are no protection ways for intellectual property created by GIS web-map service users and user's privacy. In this paper, we proposed a location and user information hiding scheme for GIS web-map service. This scheme embeds location and user information into a picture that is taken by camera module on the mobile phone. It is not only protecting way for user's privacy but is also tracing way against illegal photographer who is peeping person through hidden camera. And than, we also realized proposed scheme on the mobile smart phone. For minimizing margin of error about location coordinate value against contents manipulating attacks, GPS information is embedded into chrominance signal of contents considering weight of each digit about binary type of GPS coordinate value. And for tracing illegal photographer, user information such as serial number of mobile phone, phone number and photographing date is embedded into frequency spectrum of contents luminance signal. In the experimental results, we confirmed that the error of extracted information against various image processing attacks is within reliable tolerance. And after file format translation attack, we extracted embedded information from the attacked contents without no damage. Using similarity between extracted one and original templete, we also extracted whole information from damaged chrominance signal of contents by various image processing attacks.