• 제목/요약/키워드: Factor AA

검색결과 277건 처리시간 0.027초

아라키돈산과 철 유도성 산화적 스트레스에 대한 금앵자(金櫻子) 열수 추출물의 간세포 보호 효능 (Water Extract of Rosa laevigata Michx. Protects Hepatocytes from Arachidonic Acid and Iron-mediated Oxidative Stress)

  • 고해리;제갈경환;송시연;김난이;강지원;변성희;김영우;조일제;김상찬
    • 대한본초학회지
    • /
    • 제30권6호
    • /
    • pp.7-15
    • /
    • 2015
  • Objectives : Rosa laevigata Michx. has been used for the treatment of renal disease in traditional Korean medicine. In this study, we investigated cytoprotective effect of R. laevigata water extract (RLE) against oxidative stress induced by arachidonic acid (AA) + iron.Methods : To evaluate the protective effects of RLE against AA + iron-induced oxidative stress in HepG2 cell, cell viability and changes on apoptosis-related proteins were assessed by MTT and immunoblot analyses. The effects of RLE on reduced glutathione level, production of reactive oxygen species and mitochondrial membrane potential were also monitored. Furthermore, to verify underlying molecular mechanism, NF-E2-related factor 2 (Nrf2) was examined by immunoblot analysis. Additionally, Nrf2 transactivation and its downstream target genes expression were also determined by reporter gene and realtime RT-PCR analyses.Results : RLE pretreatment (30-300 μg/ml) prevented cells from AA + iron-mediated cell death in a concentration dependent manner. In addition, 100 μg/ml RLE inhibited AA + iron-induced glutathione depletion, reactive oxygen species production and mitochondrial dysfunction. RLE accumulated nuclear Nrf2 and also transactivated Nrf2, which was evidenced by antioxidant response element- and glutathione S-transferase A2-driven luciferase activities and mRNA level of glutamate-cysteine ligase catalytic subunit, NAD(P)H:quinone oxidoreductase 1 and sestrin 2. Moreover, protective effect of RLE against AA + iron was abolished in Nrf2 knockout cells.Conclusions : These results indicate that RLE has the ability to protect hepatocyte against oxidative stress through Nrf2 activation.

A transcription factor "OsNAC075" is essential for salt resistance in rice (Oryza sativa L.)

  • Jung, Yu-Jin;Lee, Myung-Chul;Kang, Kwon-Kyoo
    • Journal of Plant Biotechnology
    • /
    • 제38권1호
    • /
    • pp.94-104
    • /
    • 2011
  • Salt stress is a major environmental factor influencing plant growth and development. To identify salt tolerance determinants, we systematically screened salt sensitive rice mutants by use of the Activator/Dissociation (Ac/Ds) transposon tagging system. In this study, we focused on the salt sensitive mutant line, designated SSM-1. A gene encoding a NAC transcription factor homologue was disrupted by the insertion of a Ds transposon into SSM-1 line. The OsNAC075 gene (EU541472) has 7 exons and encodes a protein (486-aa) containing the NAC domain in its N-terminal region. Sequence comparison showed that the OsNAC075 protein had a strikingly conserved region at the N-terminus, which is considered as the characteristic of the NAC protein family. OsNAC075 protein was orthologous to Arabidopsis thaliana ANAC075. Phylogenetic analysis confirmed OsNAC075 belonged to the OsNAC3 subfamily, which plays an important role in response to stress stimuli. RT-PCR analysis showed that the expression of OsNAC075 gene was rapidly and strongly induced by stresses such as NaCl, ABA and low temperature ($4^{\circ}C$). Our data suggest that OsNAC075 holds promising utility in improving salt tolerance in rice.

Optimization of Human Embryonic Stem Cells into Differentiation of Dopaminergic Neurons in Vitro: I. Additive Effect of Neurotrophic Factor on Human Embryonic Stem Cells

  • 이금실;김은영;이영재;신현아;조황윤;이훈택;정길생;박세필;임진호
    • 한국동물번식학회:학술대회논문집
    • /
    • 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
    • /
    • pp.79-79
    • /
    • 2003
  • Embryonic stem cells are capable of differentiating into a variety of cell lineages. However, the ultimate results of differentiation in vitro greatly depend on the duration of treatment and kinds of differentiating inducers added. In order to investigate the efficiencies of various differentiation inducers and the methods of treatment, we examined differentiation patterns of human embryonic stem cell (hESC, MB03) according to several different protocols. Exp. I) Upon differentiation using retinoic acid and ascorbic acid (RA/AA), embryoid bodies (EB, for 4days) derived from hESC was exposed to Rh (10$^{-6}$ M) and AA (50 mM) for 4 days, and were allowed to differentiate in N2 medium for 7, 14, 21, or 28 days. Exp. II) When bFGF was used, neuronal precursor cells were selected for 8 days in N2 medium after EB formation. After selection, cells were expanded at the presence of bFGF (20 ng/ml) for another 6 days followed by a final differentiation in N2 medium for 7, 14, 21 or 28 days. Exp. III) In addition, to examine the effects of neurotrophic factors in the production of mature neurons, groups of cells were exposed to either BDNF (5 ng/ml) or TGF-$\alpha$(10 ng/ml) during the 28 days of final differentiation. Differentiation patterns of RA/AA or bFGF treated groups were very similar; approximately 82% and 83% of the cells, respectively, were positive for anti-NF200 antibody, while it was about 10% and 11%, respectively, for anti-NF160 antibody in 28 days in N2 medium. Alsor, cells expressing TH were as low as 5%, while the cells doubled when matured at the presence of either BDNF or TGF-$\alpha$. Cells immunoreactive to anti-GAD antibody were approximately 20%. These results suggest that a maturation step rather than differentiation induction step, which is formation of EB, effects more decisively to the ultimate differentiation pattern.

  • PDF

Expression, Purification, Crystallization and Preliminary X-Ray Crystallographic Analysis of CnrX from Cupriavidus metallidurans CH34

  • Kim, Kook-Han;Jung, Eun-Jung;Im, Ha-Na;Lelie, Daniel Van Der;Kim, Eunice Eun-Kyeong
    • Journal of Microbiology and Biotechnology
    • /
    • 제18권1호
    • /
    • pp.43-47
    • /
    • 2008
  • The nickel and cobalt resistance of Cupriavidus metallidurans CH34 is mediated by the CnrCBA efflux pump encoded by the cnrYHXCBAT metal resistance determinant. The products of the three genes cnrYXH transcriptionally regulate expression of cnr. CnrY and CnrX are membrane-bound proteins, probably functioning as anti-sigma factors, whereas CnrH is a cnr-specific extracytoplasmic functions (ECF) sigma factor. The periplasmic domain of CnrX (residues 29-148) was cloned as a N-terminal His-tagged protein, expressed in Escherichia coli, and purified using affinity chromatography and gel filtration. The molecular mass was estimated to be about 13.6kDa by size exclusion chromatography, corresponding to a monomer. The tetragonal bipyramid crystals were obtained by mixing an equal volume of protein in 50mM Tris-HCl, pH 7.5, 1% glycerol, 100mM NaCl, 1mM DTT, and the reservoir solution of 15% w/v PEG 2000, 100mM lithium chloride at 277K in 2-4 days using hanging drop vapor diffusion. The protein concentration was 24mg/ml. The crystal that diffracted to $2.42{\AA}$ resolution belongs to space group $P4_1\;or\;P4_3$ with unit cell parameters of $a=b=32.14{\AA},\;c=195.31{\AA},\;{\alpha}={\beta}={\gamma}=90^{\circ}$, with one molecule of CnrX in the asymmetric unit.

Invention of Ultralow - n SiO2 Thin Films

  • Dung, Mai Xuan;Lee, June-Key;Soun, Woo-Sik;Jeong, Hyun-Dam
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
    • /
    • pp.281-281
    • /
    • 2010
  • Very low refractive index (<1.4) materials have been proved to be the key factor improving the performance of various optical components, such as reflectors, filters, photonic crystals, LEDs, and solar cell. Highly porous SiO2 are logically designed for ultralow refractive index materials because of the direct relation between porosity and index of refraction. Among them, ordered macroporous SiO2 is of potential material since their theoretically low refractive index ~1.10. However, in the conventional synthesis of ordered macroporous SiO2, the time required for the crystallization of organic nanoparticles, such as polystyrene (PS), from colloidal solution into well ordered template is typical long (several days for 1 cm substrate) due to the low interaction between particles and particle - substrate. In this study, polystyrene - polyacrylic acid (PS-AA) nanoparticles synthesized by miniemulsion polymerization method have hydrophilic polyacrylic acid tails on the surface of particles which increase the interaction between particle and with substrate giving rise to the formation of PS-AA film by simply spin - coating method. Less ordered with controlled thickness films of PS-AA on silicon wafer were successfully fabricated by changing the spinning speed or concentration of colloidal solution, as confirmed by FE-SEM. Based on these template films, a series of macroporous SiO2 films whose thicknesses varied from 300nm to ~1000nm were fabricated either by conventional sol - gel infiltration or gas phase deposition followed by thermal removal of organic template. Formations of SiO2 films consist of interconnected air balls with size ~100 nm were confirmed by FE-SEM and TEM. These highly porous SiO2 show very low refractive indices (<1.18) over a wide range of wavelength (from 200 to 1000nm) as shown by SE measurement. Refraction indices of SiO2 films at 633nm reported here are of ~1.10 which, to our best knowledge, are among the lowest values having been announced.

  • PDF

Synthesis, Structure and Magnetic Properties of Mn12 Single Molecule Magnet Containing 4-(Methylthio)benzoate as Peripheral Ligands

  • Lim, Jin-Mook;Do, Young-Kyu;Kim, Jin-Kwon
    • Bulletin of the Korean Chemical Society
    • /
    • 제26권7호
    • /
    • pp.1065-1070
    • /
    • 2005
  • $[Mn_{12}O_{12}(O_2CPh-4-SMe)_{16}(H_2O)_4]{\cdot}7CH_2Cl_2$ (1), a new single-molecule magnet complex has been successfully synthesized by substitution of acetate ligand of Mn12ac with 4-(methylthio)benzoic acid. Complex 1 crystallizes into triclinic P$\overline{1}$ with a = 18.321(3) $\AA$, b = 19.011(3) $\AA$, c = 27.230(4) $\AA$, $\alpha$ = 86.973(3)$^{\circ}$, $\beta$ = 76.919(3)$^{\circ}$, $\gamma$ = 87.613(3)$^{\circ}$, and Z = 2. In complex 1, one Mn(III) ion has an abnormal Jahn-Teller elongation axis oriented at an oxide ion. Complex 1 has two out-of-phase ac susceptibility peaks in the 2-4 K and 4-7 K regions. Effective anisotropy energy barrier and pre-exponential factor are $U_{eff}$ = 45.95 K, 1/$\tau$0 = 8.6 ${\times}\;10^9s^{-1}\;for\;{\chi}_M$'' peaks in the lower temperature region and $U_{eff}$ = 59.45 K, 1/$\tau_0$ = 2.2 ${\times}\;10^8\;s^{-1}$ for $\chi_M$'' peaks in the higher temperature region. The parameters of S = 10, g = 1.87, D = -0.40 $cm^{-1}$, and E = 0.00034 $cm^{-1}$ were obtained from the M/N${\mu}_B$ vs. H/T plot of complex 1.

Cholesteryl Pentyl Carbonate의 결정 및 분자구조 (Structure of Cholesteryl Pentyl Carbonate)

  • 서혜란;박영자
    • 대한화학회지
    • /
    • 제34권1호
    • /
    • pp.29-36
    • /
    • 1990
  • Cholesteryl pentyl carbonate $(C_{33}H_{56}O_3)$의 분자 및 결정구조를 X-선 회절법으로 연구하였다. 이 결정은 단사정계에 속하며 공간군은$P2_1$이며, 단위세포 상수는 a = 12.484(3), b = 9.043(3), c = 14.053(3)$\AA$, ${\beta} = 94.12(2)^{\circ}$이다. Four-circle automatic diffractometer로 회절 강도들을 얻었으며, 구조는 cholesteryl octanoate의 원자좌표를 시행구조로 이용 결정하였고 최소자승법으로 정밀화하였다. 최종 신뢰도 R 값은 1164개의 반점들에 대하여 0.12이었다. Cholesteryl부분의 결합길이와 결합각은 정상적이나 pentyl기는 이 영역에서의 열적 진동 때문에 결합길이가 짧았다. b-축을 따르는 $2_1$ screw symmetry에 의해 관련된 인접한 분자들은 서로 반대로 나란히 놓여 있으며 monolayer를 형성하고 있다. Monolayer 내에서 cholesteryl군들이 서로 촘촘히 쌓인 구조를 만들어 Monolayer Type II packing mode에 해당하며, cholesteryl hexanoate, octanoate, hexyl carbonate, oleate 등의 결정구조들과 비슷한 구조로 되어 있다.

  • PDF

Evolving live load criteria in bridge design code guidelines - A case study of India based on IRC 6

  • Karthik, P.;Sharma, Shashi Kant;Akbar, M. Abdul
    • Structural Monitoring and Maintenance
    • /
    • 제9권1호
    • /
    • pp.43-57
    • /
    • 2022
  • One of the instances which demand structural engineer's greatest attention and upgradation is the changing live load requirement in bridge design code. The challenge increases in developing countries as the pace of infrastructural growth is being catered by the respective country codes with bigger and heavier vehicles to be considered in the design. This paper presents the case study of India where Indian Roads Congress (IRC) codes in its revised version from 2014 to 2017 introduced massive Special vehicle (SV) around 40 m long and weighing 3850 kN to be considered in the design of road bridges. The code does not specify the minimum distance between successive special vehicles unlike other loading classes and hence the consequences of it form the motivation for this study. The effect of SV in comparison with Class 70R, Class AA, Class A, and Class B loading is studied based on the maximum bending moment with moving load applied in Autodesk Robot Structural Analysis. The spans considered in the analysis varied from 10 m to 1991 m corresponding to the span of Akashi Kaikyo Bridge (longest bridge span in the world). A total of 182 analyses for 7 types of vehicles (class B, class A, class 70R tracked, class 70R wheeled, class AA tracked, AA wheeled, and Special vehicle) on 26 different span lengths is carried out. The span corresponding to other vehicles which would equal the bending moment of a single SV is presented along with a comparison relative to Standard Uniformly Distributed Load. Further, the results are presented by introducing a new parameter named Intensity Factor which is proven to relate the effect of axle spacing of vehicle on the normalized bending moment developed.

아라키돈산과 철 유도성 산화적 스트레스에 대한 억간산가진피반하(抑肝散加陳皮半夏)의 간세포 보호 효능 (Ukgan-san plus Citri Pericarpium and Pinelliae Rhizoma Protects Hepatocytes from Arachidonic Acid and Iron-mediated Oxidative Stress)

  • 김예림;진효정;박상미;제갈경환;송창현;김경순;변성희;김상찬
    • 대한한의학방제학회지
    • /
    • 제31권4호
    • /
    • pp.265-281
    • /
    • 2023
  • Objectives : Ukgan-san plus Citri Pericarpium and Pinelliae Rhizoma (UCP) is used as a traditional herbal formula in Korea and Japan for treatment of fever, fever-induced convulsions, and liver dysfunction and so on. In this study, we investigated the cytoprotective effect and underlying mechanism of UCP against oxidative stress induced by cotreatment of arachidonic acid (AA) and iron. Methods : To evaluate the hepatoprotective effects of UCP against AA + iron-induced oxidative stress in HepG2 cell, cell viability and changes on apoptosis-related proteins were assessed by MTT and immunoblot analyses. The changes in intracellular reactive oxygen species (ROS), glutathione (GSH), and mitochondrial membrane permeability (MMP) were investigated against to the oxidative stress. Furthermore, to verify underlying molecular mechanism, NF-E2-related factor 2 (Nrf2) and its downstream target genes were examined by immunoblot analysis. Results : Treatment of UCP increased the cell viability and altered the expression levels of apoptosis-related proteins such as PARP, caspase-9, caspase-3, Bcl-2. UCP also inhibited the GSH depletion, excessive ROS production and mitochondrial dysfunction induced by AA + iron. In addition, the Nrf2 and the Nrf2 target genes activation were increased by UCP. Conclusions : These results indicated that UCP has the ability to protect against oxidative stress-induced hepatocyte damage, which may be mediated with Nrf2 pathway.

Superoxide에 의존하여 내피세포에서 유리되는 이완성 물질의 특성에 대한 실험적 연구 (Characterization of Superoxide-dependent Endothelial Relaxing Factor(s))

  • 이기남;이원석;임병용;홍기환
    • 대한약리학회지
    • /
    • 제26권2호
    • /
    • pp.145-152
    • /
    • 1990
  • 최근 본 교실에서는 two-bath system을 이용하여 혈관 내피세포에서 superoxide에 의존한 혈관 이완성 물질을 동정하여 발표하였다. 본 실험에서는 상기 system을 이용하여 돼지의 관상동맥 내피세포에서 유리되는 superoxide에 의존한 이완성 물질이 고양이의 흥부 대동맥 내피 및 소의 대동맥 배양내피세포에서 얻어진 이완성 물질에 의한 이완과 매우 유사함을 관찰하여 다음과 같은 결과를 얻었다. 1. 고양이 흥부 대동맥, 돼지 관상동맥의 내피세포 및 소 대동맥 배양 내피세포 등에서 유리되는 superoxide에 의존한 이완 물질은 모두 유사한 이완 작용을 나타내었다. 2. 돼지 관상 동맥 내피세포에서 유리되는 superoxide 의존성 이완 물질이 고양이의 흥부 대동맥 내피세포나 소의 대동맥 배양 내피세포에서 유리되는 이완 물질과는 다소 다른 점도 있었다. 즉, 돼지 관상동맥 내피세포에서 유리되는 이완 물질의 작용은 catalase나 superoxide dismutase(SOD)에 의하여 억제되었으나, 후자의 두 동맥 내피세포에서 유리되는 이완 물질은 SOD에 의해서만 억제되었다. 3. 이러한 이완성 물질들의 생성은 여러 lipoxygenase억제제인 gossypol, nordihydroguaiaretic acid, AA 861 및 eicosatetraynoic acid 등의 전처치에 의하여 봉쇄되었다. 4. Cyclooxygenase 억제제인 indomethacin이 나 cytochrome P-450 monooxygenase 억제제인 proadifen과 cimetidine에 의하여는 봉쇄되지 아니하였다. 이상의 결과로부터 이러한 이완성 물질들은 비록 각기 다른 종의 동물 모델에서 얻었다고 하더라도 장기에 따라 다소 반응의 차이는 있으나 동질성 이완 물질이며, 나아가 이러한 이완성 물질은 여러 조직의 허혈-재관류 손상에 있어서 병리생리학적으로 관련될 것으로 사료된다.

  • PDF