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141.
Peter G. K. Clark Dr. Lucas C. C. Vieira Dr. Cynthia Tallant Dr. Oleg Fedorov Dr. Dean C. Singleton Dr. Catherine M. Rogers Octovia P. Monteiro James M. Bennett Dr. Roberta Baronio Dr. Susanne Müller Dr. Danette L. Daniels Jacqui Méndez Prof. Dr. Stefan Knapp Dr. Paul E. Brennan Prof. Dr. Darren J. Dixon 《Angewandte Chemie (International ed. in English)》2015,54(21):6217-6221
The bromodomain‐containing proteins BRD9 and BRD7 are part of the human SWI/SNF chromatin‐remodeling complexes BAF and PBAF. To date, no selective inhibitor for BRD7/9 has been reported despite its potential value as a biological tool or as a lead for future therapeutics. The quinolone‐fused lactam LP99 is now reported as the first potent and selective inhibitor of the BRD7 and BRD9 bromodomains. Development of LP99 from a fragment hit was expedited through balancing structure‐based inhibitor design and biophysical characterization against tractable chemical synthesis: Complexity‐building nitro‐Mannich/lactamization cascade processes allowed for early structure–activity relationship studies whereas an enantioselective organocatalytic nitro‐Mannich reaction enabled the synthesis of the lead scaffold in enantioenriched form and on scale. This epigenetic probe was shown to inhibit the association of BRD7 and BRD9 to acetylated histones in vitro and in cells. Moreover, LP99 was used to demonstrate that BRD7/9 plays a role in regulating pro‐inflammatory cytokine secretion. 相似文献
142.
143.
F.T. Dias V.N. Vieira M.L. de Almeida A.L. Falck P. Pureur J.L. Pimentel X. Obradors 《Physica C: Superconductivity and its Applications》2010
We report on systematic field-cooled magnetization experiments in an Y0.98Ca0.02Ba2Cu3O7?δ single crystal and melt-textured YBa2Cu3O7?δ samples. Magnetic fields up to 50 kOe were applied and a paramagnetic response related to the superconducting state was observed. We discuss our results in terms of the flux compression scenario into the sample. 相似文献
144.
145.
R. S. Kraußhar M. M. Rodrigues N. Vieira 《Mathematical Methods in the Applied Sciences》2015,38(18):5305-5319
G. R. Franssens In this paper, we present an explicit construction for the fundamental solution of the heat operator, the Schrödinger operator, and related first‐order parabolic Dirac operators on a class of some conformally flat non‐orientable orbifolds. More concretely, we treat a class of projective cylinders and tori where we can study parabolic monogenic sections with values in different pin bundles. We present integral representation formulas together with some elementary tools of harmonic analysis that enable us to solve boundary value problems on these orbifolds. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
146.
147.
Vinicius F. Moreira Rodrigo R. Oliveira Leda Mathias Raimundo Braz‐Filho Ivo J. Curcino Vieira 《Helvetica chimica acta》2010,93(9):1751-1757
A phytochemical study on Borreria verticillata has led to the isolation of two novel simple indole alkaloids, 6‐methoxy‐4‐(3‐methylbut‐2‐en‐1‐yl)‐1H‐indole, named verticillatine A ( 1 ), and 1‐(1H‐indol‐6‐yl)‐3‐methylbutan‐1‐one, named verticillatine B ( 2 ), one new iridoid, 6′‐O‐(2‐glyceryl)scandoside methyl ester ( 3 ), with the glycerol unit linked to a glucose unit, and two known ones, asperuloside ( 4 ) and scandoside methyl ester ( 5 ). The structures of these compounds were elucidated on the basis of spectroscopic‐data analyses, mainly 1H‐ and 13C‐NMR, including 2D experiments (1H,1H‐COSY, NOESY, HMBC, and HMQC), and HR‐ESI‐MS. 相似文献
148.
Isadora S. Vieira Dimas A.M. Zaia Solange P. Balena Antonio S. Mangrich Henrique de Santana 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):769-772
The reaction between p-benzoquinone (PBQ) and casein (protein) in the solid state was studied. After reaction with protein, the FT-IR spectra showed a new band at 1215 cm?1, with an intense sign attributed for casein/PBQ product. An optimum amount of PBQ for determination of the product when mixed with casein was 100 mg and a reaction time of 30 min. The product was stable for a period of 24 h after the reacting by heating. The interaction of PBQ with casein was investigated by FT-IR, reflectance, Raman and EPR spectroscopies. The reaction between PBQ and casein in the solid state yields a radical species (p-benzosemiquinone) that it is stabilized by the presence of p-biphenolate and p-benzoquinone species in the solid state. 相似文献
149.
Paul P. Horley Vítor R. Vieira Peter M. Gorley Vitalii K. Dugaev Jamal Berakdar Józef Barna? 《Journal of magnetism and magnetic materials》2010,322(9-12):1373-1376
One of the important requirements for spintronic devices concerns an efficient magnetization reversal, which may eventually lead to ultra-fast non-volatile magnetic memory applications. In particular, it is necessary to achieve stable sub-nanosecond switching times and to reduce magnetization “ringing”, so that the reversal will proceed along the shortest ballistic path connecting the initial and the target magnetization states. This paper is dedicated to the numerical simulations of a mono-domain ferromagnetic particle, described by the Landau–Lifshitz–Gilbert equation. We study the general case of arbitrary orientation of the applied field/current pulses, constructing dynamic diagrams for the reversal time. We have found that even short 50 ps pulses, applied at a proper angle, will induce magnetization reversal with minimal ringing effects. 相似文献
150.
Amal Al-Kahlout Diogo Vieira César O. Avellaneda Edson R. Leite Michel A. Aegerter Agnieszka Pawlicka 《Ionics》2010,16(1):13-19
Proton-conducting gel polymer electrolytes based on gelatin plasticized with glycerol and containing acetic acid were investigated,
characterized, and applied to electrochromic window. For glycerol contents varying from 7% to 48%, the conductivity of the
uniform and predominantly amorphous gel electrolyte was found to follow a Vogel–Tamman–Fulcher behavior with the temperature.
Typically, for the electrolyte chosen to make 7 × 2 cm2 electrochromic smart window with the configuration: glass/fluor-doped tin oxide (FTO)/WO3/gelatin electrolyte/CeO2–TiO2/FTO/glass and containing 28% of glycerol, the conductivities were found to be of the order of 5 × 10−5 S/cm at room temperature and 3.6 × 10−4 S/cm at 80 °C. The device was characterized by spectroelectrochemical techniques and was tested up to 10,000 cycles showing
a fast coloring/bleaching behavior, where the coloring process was achieved in 10 s and the bleaching in 2 s. The transmission
variation at the wavelength of 550 nm was about 15%. The cyclic voltammograms showed a very good reversibility of the cathodic/anodic
processes, and the charge density was about 3.5 mC/cm2. The memory tests showed that the transmittance in the colored state increased by 8% in 90 min after removing the potential. 相似文献