• Title/Summary/Keyword: BH

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The Role and Regulation of MCL-1 Proteins in Apoptosis Pathway

  • Bae, Jeehyeon
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2002.07a
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    • pp.113-113
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    • 2002
  • Phylogenetically conserved Bcl-2 family proteins play a pivotal role in the regulation of apoptosis from virus to human. Members of the Bcl-2 family consist of antiapoptotic proteins such as Bcl-2, Bcl-xL, and Bcl-w, and proapoptotic proteins such as BAD, Bax, BOD, and Bok. It has been proposed that anti- and proapoptotic Bcl-2 proteins regulate cell death by binding to each other and forming heterodimers. A delicate balance between anti- and proapoptotic Bcl-2 family members exists in each cell and the relative concentration of these two groups of proteins determines whether the cell survives or undergoes apoptosis. Mcl-1 (Myeloid cell :leukemia-1) is a member of the Bcl-2 family proteins and was originally cloned as a differentiation-induced early gene that was activated in the human myeloblastic leukemia cell line, ML-1 . Mcl-1 is expressed in a wide variety of tissues and cells including neoplastic ones. We recently identified a short splicing variant of Mcl-1 short (Mcl-IS) and designated the known Mcl-1 as Mcl-1 long (Mcl-lL). Mcl-lL protein exhibits antiapoptotic activity and possesses the BH (Bcl-2 homology) 1, BH2, BH3, and transmembrane (TM) domains found in related Bcl-2 proteins. In contrast, Mcl-1 S is a BH3 domain-only proapoptotic protein that heterodimerizes with Mcl-lL. Although both Mc1-lL and Mcl-lS proteins contain BH domains fecund in other Bcl-2 family proteins, they are distinguished by their unusually long N-terminal sequences containing PEST (proline, glutamic acid, serine, and threonine) motifs, four pairs of arginine residues, and alanine- and glycine-rich regions. In addition, the expression pattern of Mcl-1 protein is different from that of Bcl-2 suggesting a unique role (or Mcl-1 in apoptosis regulation. Tankyrasel (TRF1-interacting, ankyrin-related ADP-related polymerasel) was originally isolated based on its binding to TRF 1 (telomeric repeat binding factor-1) and contains the sterile alpha motif (SAM) module, 24 ankyrin (ANK) repeats, and the catalytic domain of poly(adenosine diphosphate-ribose) polymerase (PARP). Previous studies showed that tankyrasel promotes telomere elongation in human cells presumably by inhibiting TRFI though its poly(ADP-ribosyl)action by tankyrasel . In addition, tankyrasel poly(ADP-ribosyl)ates Insulin-responsive amino peptidase (IRAP), a resident protein of GLUT4 vesicles, and insulin stimulates the PARP activity of tankyrase1 through its phosphorylation by mitogen-activated protein kinase (MAPK). ADP-ribosylation is a posttranslational modification that usually results in a loss of protein activity presumably by enhancing protein turnover. However, little information is available regarding the physiological function(s) of tankyrase1 other than as a PARP enzyme. In the present study, we found tankyrasel as a specific-binding protein of Mcl-1 Overexpression of tankyrasel led to the inhibition of both the apoptotic activity of Mel-lS and the survival action of Mcl-lL in mammalian cells. Unlike other known tankyrasel-interacting proteins, tankyrasel did not poly(ADP-ribosyl)ate either of the Mcl-1 proteins despite its ability to decrease Mcl-1 proteins expression following coexpression. Therefore, this study provides a novel mechanism to regulate Mcl-1-modulated apoptosis in which tankyrasel downregulates the expression of Mcl-1 proteins without the involvement of its ADP-ribosylation activity.

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Magenetic Properties of Nd-Fe-B-Co-based Melt-spun Ribbons an dTheir Bonded Magents (Nd-Fe-B-Co계 급냉리본과 Bond 자석의 자기적 성질)

  • Gang, Gye-Myeong;Gang, Gi-Won;O, Yeong-Min;Song, Jin-Tae
    • Korean Journal of Materials Research
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    • v.3 no.2
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    • pp.175-184
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    • 1993
  • Abstract Co-and/or AI-added Nd-Fe-B-based magnetic alloys were fabricated by using vacuum induction melting frunace, and melt-spun ribbons were made of the magnetic alloys with single roll rapid quenching method. The variation of magnetic properties of the melt-spun ribbons as a function of Cuwheel velocity (Vs) were investigated. Bonded magnets were made of the optimally quenched ribbon fragments, and the magnetic properties of the melt-spun ribbons and the bonded magnets were studied, relating to the microstructure and crystalline structure. Cu-wheel surface velocity had a strong effect on the magnetic properties of the melt-spun ribbons, and the maximum properties were obtained around Vs =20m/sec. The optimally quenched ribbon had a cellura-type microstructure, in which fine N$d_2$F$e_14$B grains were surrounded by thin Nd-rich phase. In case of a 2.1at% AI-added melt-spun ribbon, the magnetic properties were as follows: iHc, Br, and (BH)max were 15.5KOe, 7.8KG and 8.5MGOe respectively. And resin bonded magnets were fabricated by mixing optimally quenched ribbon fragments with 2.5wt % polyamide resin, compacting and binding at room temperature. The iHc, Br and (BH)max of bonded magnet were lO.2KOe, 4.4KG and 3.3MGOe respectively. And hot-pressed magnets were made by pressing the overquenched ribbons at high temperature. The magnetic properties of hot-pressed magnets were better than those of bonded magnets, and when the holding time was 8 minutes, the iHc, Br, and (BH)max of the hot-pressed magnet were 1O.8KOe, 7.3KG and 8.0MGOe respectively. Domain structure was mainly maze pattern, which means that the easy magnetization axis could be aligned, and the domain width of the hot-pressed magnets was smaller than that of bonded magnets.

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(Pyridine)(tetrahydroborato)zinc Complex, [Zn(BH4)2(py)], as a New Stable, Efficient and Chemoselective Reducing Agent for Reduction of Carbonyl Compounds

  • Zeynizadeh, Behzad;Faraji, Fariba
    • Bulletin of the Korean Chemical Society
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    • v.24 no.4
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    • pp.453-459
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    • 2003
  • (Pyridine)(tetrahydroborato)zinc complex, $[Zn(BH_4)_2(py)]$, as a stable white solid, was prepared quantitatively by complexation of an equimolar amount of zinc tetrahydroborate and pyridine at room temperature. This reagent can easily reduce variety of carbonyl compounds such as aldehydes, ketones, acyloins, α-diketones and a, β-unsaturated carbonyl compounds to their corresponding alcohols in good to excellent yields. Reduction reactions were performed in ether or THF at room temperature or under reflux conditions. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing agent.

Investigating the cosmic evolution of the black hole mass-bulge luminosity scaling relation

  • Park, Daeseong;Woo, Jong-Hak;Treu, Tommaso;Bennert, Vardha N.;Malkan, Matthew A.;Auger, Matthew W.
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.42.2-42.2
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    • 2013
  • We investigate the cosmic evolution of the black hole mass-bulge luminosity relation with a sample of 52 moderate-luminosity AGNs at $z{\simeq}0.36$ and $z{\simeq}0.57$, corresponding to look-back times of 4 and 6 Gyrs. By employing robust multi-component spectral and structural decomposition methods to the obtained high-quality Keck spectra and high-resolution HST images, black hole masses ($M_{BH}$) are estimated from the Hbeta broad emission line with the 5100A nuclear luminosity, and bulge luminosities ($L_{bul}$) are derived from the surface photometry. Based on these consistent measurements, we constrain the redshift evolution of the $M_{BH}-L_{bul}$ relation by performing the Monte Carlo simulations designed to account for selection effects. We provide implications of our results in terms of the black hole-galaxy co-evolution and discuss possible bulge growth mechanisms.

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Research Trends in Efficient Transmission Techniques Based on DVB-S2x Standard for Multi-beam HTS and Beam Hopping Satellite System (DVB-S2x 표준기반 다중빔 위성 전송기술 동향)

  • Kim, P.;Ryu, J.G.;Oh, D.G.;Yom, I.B.;Lee, H.J.
    • Electronics and Telecommunications Trends
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    • v.33 no.3
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    • pp.34-40
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    • 2018
  • Current studies based on the DVB-S2x standard for the next-generation multi-beam HTS/BH satellite have been investigated. To enhance the efficiency of the transmission throughput and maximize the utilization of the satellite payload resources and bandwidth, the concepts of two advanced techniques, namely, precoding and BH, are described. Furthermore, state-of-the-art aspects currently under discussion, and future study items in the DVB TM-S standardization group, are summarized in this article.

서울 지하철 A설계구간에서의 지하수 수질 및 오염특성

  • 이병선;한원식;김연태;우남칠;홍원석
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.04a
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    • pp.225-228
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    • 2002
  • 서울 지하철 A설계구간에서의 전체 21개 지하수 시료에 대하여 수질분석을 실시하였다. 배경수질은 주로 Ca-HCO$_3$ type으로 전 지역에서의 물-암석 반응 자체는 큰 차이가 없음을 보인다. 본 조사에서 실시한 분석요소 중, 먹는 물 기준치를 초과하지 않은 시료는 3개이며, 나머지 18개 시료는 중금속과 불소, 황산염 등에 의해 이미 오염되어 있는 것으로 나타났다. 지하수 오염도는 BH-l~5 지역에서 보이는 카드뮴에 의한 오염현상과 BH-6~23 지역에서 보이는 다른 중금속 이온들에 의한 오염으로 뚜렷한 지역적인 차이가 보이는데, 이는 자연적인 지하매질과 지하수의 물-암석 반응에 의한 것이기보다는, 이들 지역에 매립된 인위적인 오염물질의 차이에 의해 결정되는 것으로 추정된다.

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Non-Linearity of the Seminormed Fuzzy Integral (준노름 퍼지적분의 비 선형성)

  • Kim, Mi-Hye
    • The Journal of the Korea Contents Association
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    • v.2 no.2
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    • pp.91-97
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    • 2002
  • Let (X, F, g) be a fuzzy measure space. Then for any h$\in$ $L^{0}$ (X) , a$\in$[0 , 1] , and $A\in$F ∫$_{A}$aㆍh($\chi$)┬g=aㆍ∫$_{A}$h($\chi$)┬g with the t-seminorm ┬(x, y)= xy. And we prove that the Seminormed fuzzy integral has some linearity properties only for {0,1}-classes of fuzzy measure as follow, For any f, h$\in$ $L^{0}$ ($\chi$), any a, b$\in$R+: af+bh$\in$ $L^{0}$ ($\chi$)⇒ ∫$_{A}$(af+bh)┬g=a∫$_{A}$f┬g+b∫$_{A}$h┬g; if and only if g is a probability measure fulfilling g(A) $\in${0, 1} for all $A\in$F.n$F.

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Effects of Steel Chemistry, Annealing and Galvannealing Conditions on Bake Hardenability of Hot-Dip Galvannealed Sheet Steels (합금화 용융아연 도금강판의 강성분, 소둔 및 합금화 열처리가 소부경화성에 미치는 영향)

  • 이호종;김종상
    • Journal of Surface Science and Engineering
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    • v.34 no.3
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    • pp.247-257
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    • 2001
  • In an effort to improve the dent resistance of exterior body panels at a reduced steel thickness, the bake hardenable steels added Ti or Nb with tensile strength of 35Kgf/$\textrm{mm}^2$ were investigated. The bake hardenability increased with the annealing temperature and solute carbon content. Bake hardening of 3 to 5Kgf/$\textrm{mm}^2$ was obtained in steels with a controlled solute carbon concentration range from 6 to 10ppm. The galvannealing temperature and time had little influence on the bake hardenability. The Fe-Zn alloying reaction of 35Kgf/$\textrm{mm}^2$ BH steel was remarkably retarded due to a 0.07%P addition. The optimum galvannealing temperatures of 35Kgf/$\textrm{mm}^2$ BH steel were ranged from 520 to 56$0^{\circ}C$ in view of the Fe content and powdering resistance. The cross-section and planar views of the galvannealed coatings to characterize morphology development were discussed.

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