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showing 10 items of 1921 documents
Design, synthesis, and biological evaluation of thiophene analogues of chalcones.
2008
Chalcones are characterized by possessing an enone moiety between two aromatic rings. A series of chalcone-like agents, in which the double bond of the enone system is embedded within a thiophene ring, were synthesized and evaluated for antiproliferative activity and inhibition of tubulin assembly and colchicine binding to tubulin. The replacement of the double bond with a thiophene maintains antiproliferative activity and therefore must not significantly alter the relative conformation of the two aryl rings. The synthesized compounds were found to inhibit the growth of several cancer cell lines at nanomolar to low micromolar concentrations. In general, all compounds having significant anti…
Levels of self-consistency in the GW approximation
2009
We perform $GW$ calculations on atoms and diatomic molecules at different levels of self-consistency and investigate the effects of self-consistency on total energies, ionization potentials and on particle number conservation. We further propose a partially self-consistent $GW$ scheme in which we keep the correlation part of the self-energy fixed within the self-consistency cycle. This approximation is compared to the fully self-consistent $GW$ results and to the $G W_0$ and the $G_0W_0$ approximations. Total energies, ionization potentials and two-electron removal energies obtained with our partially self-consistent $GW$ approximation are in excellent agreement with fully self-consistent $…
Role of cyclic nucleotide phosphodiesterase isoenzymes in contractile responses of denuded rat aorta related to various Ca 2+ sources
2001
We have examined the cyclic nucleotide phosphodiesterase isoforms (PDE) involved in the contractile response of rat aorta to different agonists and different experimental procedures for use in functional studies. The inhibitory effect of AAL 05 on the different PDEs isolated from bovine aortic smooth muscle was examined. Compound AAL 05 appeared to be a selective PDE3 inhibitor. We analyzed the ability of the non-selective inhibitor IBMX (3-isobutyl-1-methylxanthine) and the isoenzyme selective inhibitors nimodipine (type 1), AAL 05 (6-(N-methyl-N-cyclohexyl butyl carboxamide) quinolin-2-one) and SKF 94120 (5-(4-acetamidophenyl) pyrazin-2(1H)-one; type3), rolipram (type4) and zaprinast (typ…
Synthesis of Enaminones-Based Benzo[d]imidazole Scaffold: Characterization and Molecular Insight Structure
2020
(E)-1-(1H-Benzo[d]imidazol-2-yl)-3-(dimethylamino)prop-2-en-1-one 2 was synthesized by one-pot synthesis protocol of 2-acetyl benzo[d]imidazole with dimethylformamide dimethylacetal (DMF-DMA) in xylene at 140 °
Electrochemical performance of activated screen printed carbon electrodes for hydrogen peroxide and phenol derivatives sensing
2019
Screen-printed carbon electrodes (SPCEs) are widely used for the electroanalysis of a plethora of organic and inorganic compounds. These devices offer unique properties to address electroanalytical chemistry challenges and can successfully compete in numerous aspects with conventional carbon-based electrodes. However, heterogeneous kinetics on SPCEs surfaces is comparatively sluggish, which is why the electrochemical activation of inks is sometimes required to improve electron transfer rates and to enhance sensing performance. In this work, SPCEs were subjected to different electrochemical activation methods and the response to H2O2 electroanalysis was used as a testing probe. Changes in to…
On approximating curves associated with nonexpansive mappings
2011
Let X be a Banach space with metric d. Let T, N : X → X be a strict d-contraction and a d-nonexpansive map, respectively. In this paper we investigate the properties of the approximating curve associated with T and N. Moreover, following [3], we consider the approximating curve associated with a holomorphic map f : B → α B and a ρ-nonexpansive map M : B → B, where B is the open unit ball of a complex Hilbert space H, ρ is the hyperbolic metric defined on B and 0 ≤ α < 1. We give conditions on f and M for this curve to be injective, and we show that this curve is continuous.
Caracterización bioquímica y funcional de la proteína MnmE de Escherichia coli, una proteína esencial implicada en la modificación de los tRNAs.
2004
El objetivo de este trabajo ha sido caracterizar, bioquímica y funcionalmente, una GTPasa bacteriana, la proteína MnmE de E. coli, implicada en la modificación postranscricional de algunos tRNAs.MnmE es una proteína multidominio de 50 kDa que consta de un dominio N-terminal de ~220 residuos, un dominio medio de unión a GTP (dominio G) de ~160 residuos y un dominio C-terminal de ~75 aminoácidos que contiene la única cisteína presente en la molécula. MnmE es una GTPasa cuyas propiedades bioquímicas difieren ampliamente de las mostradas por las GTPasas reguladoras pertenecientes a la familia de las pequeñas GTPasas, típicamente representadas por Ras. MnmE tiene muy baja afinidad por nucleótido…
Análisis genético y funcional de la frataxina y otras proteínas mitocrondriales relacionadas con ataxias cerebelosas.
2005
El déficit de frataxina es la causa principal de la ataxia de Friedreich, una enfermedad hereditaria neurodegenerativa que afecta a las neuronas sensitivas del ganglio dorsal y del tracto espinocerebelar. Desde que se describi¨® el gen responsable de la enfermedad y sobre todo gracias a la generaci¨®n de organismos modelos para su estudio, se han postulado diferentes funciones para la frataxina: homeostasis del hierro mitocondrial, almacenamiento del hierro, respuesta al estr¨¦s oxidativo. Biog¨¦nesis de los clusters Fe-S, modulaci¨®n en la actividad de la aconitasa mitocondrial y un papel en la fosforilaci¨®n oxidativa. Nuestro planteamiento ha sido que la frataxina realiza su funci¨®n en …
Tanzawaic acid derivatives from freshwater sediment-derived fungus Penicillium sp.
2018
Abstract Chemical investigation of a freshwater sediment-derived fungus, Penicillium sp. (S1a1), led to the isolation of three new tanzawaic acid derivatives, including penitanzchroman (1), tanzawaic acids Y (2) and Z (3), along with six known tanzawaic acid analogues (4-9), three known isochromans (10-12) and two known benzoquinones (13 and 14). The structures of the new compounds were established based on high-resolution mass spectrometry, and detailed analysis of one- and two-dimensional NMR spectroscopy. The relative configuration of the new compounds was assigned on the basis of NMR spectroscopic data including ROESY spectra. The absolute configuration was determined based on the speci…
Influence of prebiotics, probiotics and protein ingredients on mycotoxin bioaccessibility
2015
The aim of this study was to investigate the influence of prebiotic compounds (cellulose and inulin), food ingredients (milk whey, β-lactoglobulin and calcium caseinate) and several probiotic microorganisms on the bioaccessibility of beauvericin (BEA), enniatins (ENs A, A1, B, B1), deoxynivalenol (DON) and zearalenone (ZEA) present in wheat crispy bread produced with wheat flour previously fermented with F. tricinctum, F. culmorum and G. zeae. The bioaccessibility of mycotoxins was determined by a dynamic simulated gastrointestinal digestion system, imitating the human digestive physiological conditions of the gastrointestinal tract. Mycotoxins were determined in the simulated intestinal fl…