• Title/Summary/Keyword: May B

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Effects of Salicylic Acid on Oxidative Stress and UV-B Tolerance in Cucumber Leaves (살리실산이 오이 잎의 산화적 스트레스와 UV-B 내성에 미치는 영향)

  • Hong, Jung-Hee;Kim, Tae-Yun
    • Journal of Environmental Science International
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    • v.16 no.12
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    • pp.1345-1353
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    • 2007
  • The effect of salicylic acid(SA) on antioxidant system and protective mechanisms against UV-B induced oxidative stress was investigated in cucumber(Cucumis sativus L.) leaves. UV-B radiation and SA were applied separately or in combination to first leaves of cucumber seedlings, and dry matter accumulation, lipid peroxidation and activities of antioxidant enzymes were measured in both dose and time-dependant manner. UV-B exposure showed reduced levels of fresh weight and dry matter production, whereas SA treatment significantly increased them. SA noticeably recovered the UV-B induced inhibition of biomass production. UV-B stress also affected lipid peroxidation and antioxidant enzyme defense system. Malondialdehyde(MDA), a product of lipid peroxidation, was greatly increased under UV-B stress, showing a significant enhancement of a secondary metabolites, which may have antioxidative properties in cucumber leaves exposed to UV-B radiation. Combined application of UV-B and SA caused a moderate increase in lipid peroxidation. These results suggest that SA may mediate protection against oxidative stress. UV-B exposure significantly increased SOD, APX, and GR activity compared with untreated control plants. Those plants treated with 1.0 mM SA showed a similar pattern of changes in activities of antioxidant enzymes. SA-mediated induction of antioxidant enzyme activity may involve a protective accumulation of $H_2O_2$ against UV-B stress. Moreover, their activities were stimulated with a greater increase by UV-B+SA treatment. The UV-B+SA plants always presented higher values than UV-B and SA plants, considering the adverse effects of UV-B on the antioxidant cell system. ABA and JA, second messengers in signaling in response to stresses, showed similar mode of action in UV-B stress, supporting that they may be important in acquired stress tolerance. Based on these results, it can be suggested that SA may participates in the induction of protective mechanisms involved in tolerance to UV-B induced oxidative stress.

Grotesque Image Dance Causing Uncanny -Focusing on Maguy Marin's "May B"- (언캐니를 유발하는 그로테스크 이미지 무용에 관한 연구 -마기 마랭(Maguy Marin)의 작품 를 중심으로-)

  • Kim, Ji-In;Choe, Sang-Cheul
    • The Journal of the Korea Contents Association
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    • v.22 no.1
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    • pp.405-414
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    • 2022
  • The purpose of this study is to discover the possibility to expand the aesthetic interpretation of dance works. For this purpose, this study analyzes Maguy Marin's (1981) because it shows Sigmund Freud's concept of uncanny and grotesque images well. The theoretical framework of this study was centered on previous academic studies, and Hoffman's Der Sandmann(1816) was presented as an example to help the conceptual understanding of uncanny and grotesque. The analysis of of Magi Marin was divided into stage space, dancer's movements, costumes, and voice. As a result of this study, it was discovered that is a work with an experimental spirit that deviated from the stereotypes of traditional stage aesthetics. And it was implemented as uncanny and grotesque images in the choreography structure. In addition, as the changes of the times have a great influence on the creation of dance works, it is thought that the discourse of various aesthetic interpretation methods in dance works can provide various directions for dance creation in the future. Therefore, this study will be helpful in raising the aesthetic value and status of dance art.

CYP1B1 Activates Wnt/β-Catenin Signaling through Suppression of Herc5-Mediated ISGylation for Protein Degradation on β-Catenin in HeLa Cells

  • Park, Young-Shin;Kwon, Yeo-Jung;Chun, Young-Jin
    • Toxicological Research
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    • v.33 no.3
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    • pp.211-218
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    • 2017
  • Cytochrome P450 1B1 (CYP1B1) acts as a hydroxylase for estrogen and activates potential carcinogens. Moreover, its expression in tumor tissues is much higher than that in normal tissues. Despite this association between CYP1B1 and cancer, the detailed molecular mechanism of CYP1B1 on cancer progression in HeLa cells remains unknown. Previous reports indicated that the mRNA expression level of Herc5, an E3 ligase for ISGylation, is promoted by CYP1B1 suppression using specific small interfering RNA, and that ISGylation may be involved in ubiquitination related to ${\beta}-catenin$ degradation. With this background, we investigated the relationships among CYP1B1, Herc5, and ${\beta}-catenin$. RT-PCR and western blot analyses showed that CYP1B1 overexpression induced and CYP1B1 inhibition reduced, respectively, the expression of $Wnt/{\beta}-catenin$ signaling target genes including ${\beta}-catenin$ and cyclin D1. Moreover, HeLa cells were treated with the CYP1B1 inducer $7,12-dimethylbenz[{\alpha}]anthracene$ (DMBA) or the CYP1B1 specific inhibitor, tetramethoxystilbene (TMS) and consequently DMBA increased and TMS decreased ${\beta}-catenin$ and cyclin D1 expression, respectively. To determine the correlation between CYP1B1 expression and ISGylation, the expression of ISG15, a ubiquitin-like protein, was detected following CYP1B1 regulation, which revealed that CYP1B1 may inhibit ISGylation through suppression of ISG15 expression. In addition, the mRNA and protein expression levels of Herc5 were strongly suppressed by CYP1B1. Finally, an immunoprecipitation assay revealed a direct physical interaction between Herc5 and ${\beta}-catenin$ in HeLa cells. In conclusion, these data suggest that CYP1B1 may activate $Wnt/{\beta}-catenin$ signaling through stabilization of ${\beta}-catenin$ protein from Herc5-mediated ISGylation for proteosomal degradation.

Temperature development and cracking characteristics of high strength concrete slab at early age

  • Wu, Chung-Hao;Lin, Yu-Feng;Lin, Shu-Ken;Huang, Chung-Ho
    • Structural Engineering and Mechanics
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    • v.74 no.6
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    • pp.747-756
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    • 2020
  • High-strength concrete (HSC) generally is made with high amount of cement which may release large amount of hydration heat at early age. The hydration heat will increase the internal temperature of slab and may cause potential cracking. In this study, slab specimens with a dimension of 600 × 600 × 100 mm were cast with concrete incorporating silica fume for test. The thermistors were embedded in the slabs therein to investigate the interior temperature development. The test variables include water-to-binder ratio (0.25, 0.35, 0.40), the cement replacement ratio of silica fume (RSF; 5 %, 10 %, 15 %) and fly ash (RFA; 10 %, 20 %, 30 %). Test results show that reducing the W/B ratio of HSC will enhance the temperature of first heat peak by hydration. The increase of W/B decrease the appearance time of second heat peak, but increase the corresponding maximum temperature. Increase the RSF or decrease the RFA may decrease the appearance time of second heat peak and increase the maximum central temperature of slab. HSC slab with the range of W/B ratio of 0.25 to 0.40 may occur cracking within 4 hours after casting. Reducing W/B may lead to intensive cracking damage, such as more crack number, and larger crack width and length.

A Study on the Pre-printed Clause of the Bill of Lading (선하증권 인쇄약관에 관한 연구)

  • Park, Sae-Woon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.49
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    • pp.359-378
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    • 2011
  • UCP600 Article 20 (a) (v) states that contents of terms and conditions of carriage will not be examined and Article 34 states that a bank assumes no liability or responsibility for the general or particular conditions stipulated in a document. From this perspective, banks may seem to have no obligation to examine the pre-printed clause of B/L. However, ICC decided that no opinion could be given in relation to the issues surrounding B/Ls that contain delivery clauses. Accordingly, it is agreed by previous cases and some scholars that banks may refuse the B/Ls that contain delivery clauses which are not present in other B/Ls of the same goods and transport routes. Also, ICC published ICC Decision in July 2010 regarding on board notation. In this decision, if a B/L indicates a place of receipt that is different from the port of loading and there is an indication of a means of pre-carriage, then a dated on board notation will be required indicating the name of the vessel and the port of loading. Therefore, banks may,, in some cases, need to scrutinize the pre-printed clauses especially appearing in the front page of B/Ls.

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Induction of Cytochrome P450 by Ionones in Liver Lobes of Sprague Dawley Rats (Ionone류에 의한 랫드의 간엽별 cytochrome P450 유도 특성에 관한 연구)

  • 구희경;정태천;천영진;윤철호;노정구;최인경
    • Toxicological Research
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    • v.13 no.4
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    • pp.385-391
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    • 1997
  • Inductive effects of cytochrome P450 2B1 by $\alpha$- and $\beta$-ionone were characterized in individual liver lobes of male Sprague Dawley rats. When rats were administered ionones orally at 100, 300, and 600 mg/kg for 24 hr, cytochrome P450 2B1 was induced dose-dependently in liver S-9 fractions as measured by P450 2B-specific monooxygenases and Western immunoblotting. The activity of P450 1A- and P450 2B-specific monooxygenases was differentially expressed in each lobe of normal liver. In addition, the monooxygenase activity was induced by $\alpha$- and $\beta$-ionone with different potency in each lobe of the liver. Our present results indicate that the different induction of P450s by $\alpha$- and $\beta$-ionone in each lobe may explain different susceptibilities of rat liver lobes to certain hepatotoxicants which require metabolic activation for their toxicity and that $\alpha$- and $\beta$-ionone may be useful model inducers of P450 2B1 in studying the toxic mechanism of certain toxicants which may require the metabolic activation by P450.

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Role of NADPH Oxidase-mediated Generation of Reactive Oxygen Species in the Apigenin-induced Melanogenesis in B16 Melanoma Cells (B16 흑색종세포에서 아피제닌에 의한 멜라닌 합성에 미치는 NADPH 산화효소-유래 활성산소종의 역할)

  • Lee, Yong-Soo
    • YAKHAK HOEJI
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    • v.55 no.6
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    • pp.485-491
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    • 2011
  • Previously, we have reported that apigenin, a natural flavonoid found in a variety of vegetables and fruits, stimulated melanogenesis through the activation of $K^+-Cl^-$-cotransport (KCC) in B16 melanoma cells. In this study we investigated the possible involvement of reactive oxygen species (ROS) in the mechanism of apigenin-induced melanogenesis in B16 cells. Apigenin elevated intracellular ROS level in a dose-dependent manner. Treatment with various inhibitors of NADPH oxidase, diphenylene iodonium (DPI), apocynin (Apo) and neopterine (NP) significantly inhibited both the generation of ROS and melanogenesis induced by apigenin. In addition these inhibitors profoundly inhibited apigenin-induced $Cl^-$-dependent $K^+$ efflux, a hallmark of KCC activity. However, the apigenin-induced ROS generation was not significantly affected by treatment with a specific KCC inhibitor R-(+)-[(2-n-butyl-6,7-dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1H-inden-5-yl)oxy]acetic acid (DIOA). These results indicate that the ROS production may be a upstream regulator of the apigenin-induced KCC stimulation, and in turn, melanogenesis in the B16 cells. Taken together, these results suggest that the NADPH oxidase-mediated ROS production may play an important role in the apigenin-induced melanogenesis in B16 cells. These results further suggest that NADPH oxidase may be a good target for the management of hyperpigmentation disorders.

Effect of Chitosan Oligosaccharide on Melanin Production in B16 Melanoma Cells (B16 Melanoma 세포에서 Chitosan Oligosaccharide가 Melanin 생성에 미치는 영향)

  • 조남영;윤미연;김경원;박영미;임혜원;이지윤;이진희;김연정;김창종
    • YAKHAK HOEJI
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    • v.47 no.6
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    • pp.404-409
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    • 2003
  • To investigate the effect of chitosan oligosaccharide on melanin synthesis, we measured tyrosinase activity and melanin production in B16 melanoma cells. Chitosan oligosacchaide itself did not have any anti-oxidant activity in DPPH radical scavenging, and did not affect the proliferation of B16 melanoma cells. Chitosan oligosaccharide dose-dependently increased melanin production in the absence or presence of MSH. However, chitosan oligosaccharide did not have any influence on the tyrosinase activity and tyrosinase expression in B16 melanoma cells. These results suggest that chitosan oligosaccharide-induced melanin production may be independent on tyrosinase activity in B16 melanoma cells. From the above results. chitosan oligosaccharide dose-dependently appears to increase melanin production in B16 melanoma cells, suggesting that chitosan oligosaccharide may be used as a tanning agent.

Desing and Verification of Satellite B-ISDN Signalling Protocol (위성 B-ISDN 신호 프로토콜의 설계 및 검증)

  • Park, Seok-Cheon;Choe, Dong-Yeong;Gang, Seong-Yong
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.7
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    • pp.1909-1918
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    • 1999
  • The terrestrial/satellite hybrid network may replace or supply the terrestrial network in some areas or certain applications. For example, it may play a major role in global B-ISDN or in certain areas where the deployment of optical cable is not feasible, especially at the early stage of implementing terrestrial B-ISDN. Furthermore, it can play an important role in the development of B-ISDN due to their features of flexible wide coverage, independent of ground distances and geographical constraints, multiple access and multipoint broadcast. Also, satellite have the capability to supply terrestrial B-ISDN/ATM with flexible links for access networks as well as trunk networks. This paper describes the design and verification of the interworking protocol between terrestrial B-ISDN뭉 satellite network. For the verification, the designed interworking protocol is modeled by Petri-net and the model is analyzed by reachability tree.

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The effect of Vitamin $B_2$ Deficiency on the Utilization and Recuperation of Fuel in Exercising Rats (비타민 $B_2$ 부족이 운동중 연료의 이용과 회복에 미치는 영향)

  • 조윤옥
    • Journal of Nutrition and Health
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    • v.29 no.7
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    • pp.772-777
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    • 1996
  • The purpose of this study was to investigate the effect of vitamin B2 deficiency on the utilization and recuperation of fuel in exercising rats. Thirthy six rats were fed either a vitamin B2 deficient diet (-B2) or a control diet (+B2) for 3 weeks and then subdivided into 3 groups : non-exercise group(NE), exercise group (ES), exercise and recuperation group (ER). ES group were exercised on treadmill (10$^{\circ}$, 0.5-0.8km/h) for 2 hours and ER group were recuperated three days with the respective diet after exercise. Glucose (GLU), glycogen(GLY), protein(PRO), triglyceride(TG) and free fatty acid(FFA) were compared in plasma(P), liver(L) and skeletal muscle(M) of rats. Compared to + B2 rats, in NE group, the level of P-GLU and L-GLU of -B2 rats was lower, L-PRO and M-GLY was higher and there were no differences in P-PRO, P-FFA, L-TG and M-TG. In ES group, the level of P-GLU was lower, P-FFA was higher and there were no differences in P-PRO, P-TG, L-GLU, L-TG, M-GLY, M-TG and M-PRO. In ER groups, the level of P-GLU and L-TG was lower, P-FFA was higher and there were no differences in P-PRO, P-TG, L-GLY, L-PRO, M-GLY, M-TG and M-PRO. These results suggest that a vitamin B2 deficiency may impair the utilization of stored fuel during exercise suggest that a vitamin B2 deficiency may impair the utilization of stored fuel during exercise and may lead a sluggish recuperation related to fuel stores after exercise.

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