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91.
Di Benedetto F Camposeo A Persano L Laera AM Piscopiello E Cingolani R Tapfer L Pisignano D 《Nanoscale》2011,3(10):4234-4239
We report on the simple, in situ generation of CdS nanocrystals inside electrospun polymer fibres by thermal decomposition of a cadmium thiolate precursor, leading to nanocomposite light-emitting fibres. The modifications induced in the precursor by the thermal decomposition are investigated by a morphological, structural and spectroscopic analysis of the resulting nanocomposite fibres. This approach allows us to overcome nanofabrication difficulties related to disfavoured micro- or nanofluidic molecular flow as given by the direct incorporation of particles in the electrospinning solution. This method therefore enables the synthesis of luminescent, CdS-based composite fibres with emission peaked in the visible range, suitable as building blocks for nanophotonic devices based on light-emitting nanomaterials. 相似文献
92.
Francesca Mangiavacchi Pawel Botwina Elena Menichetti Luana Bagnoli Ornelio Rosati Francesca Marini Srgio F. Fonseca Laura Abenante Diego Alves Agnieszka Dabrowska Anna Kula-Pacurar David Ortega-Alarcon Ana Jimenez-Alesanco Laura Ceballos-Laita Sonia Vega Bruno Rizzuti Olga Abian Eder J. Lenardo Adrian Velazquez-Campoy Krzysztof Pyrc Luca Sancineto Claudio Santi 《International journal of molecular sciences》2021,22(13)
The development of new antiviral drugs against SARS-CoV-2 is a valuable long-term strategy to protect the global population from the COVID-19 pandemic complementary to the vaccination. Considering this, the viral main protease (Mpro) is among the most promising molecular targets in light of its importance during the viral replication cycle. The natural flavonoid quercetin 1 has been recently reported to be a potent Mpro inhibitor in vitro, and we explored the effect produced by the introduction of organoselenium functionalities in this scaffold. In particular, we report here a new synthetic method to prepare previously inaccessible C-8 seleno-quercetin derivatives. By screening a small library of flavonols and flavone derivatives, we observed that some compounds inhibit the protease activity in vitro. For the first time, we demonstrate that quercetin (1) and 8-(p-tolylselenyl)quercetin (2d) block SARS-CoV-2 replication in infected cells at non-toxic concentrations, with an IC50 of 192 μM and 8 μM, respectively. Based on docking experiments driven by experimental evidence, we propose a non-covalent mechanism for Mpro inhibition in which a hydrogen bond between the selenium atom and Gln189 residue in the catalytic pocket could explain the higher Mpro activity of 2d and, as a result, its better antiviral profile. 相似文献
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Valeria Ambrogi Luana PerioliCinzia Pagano Loredana LatteriniFabio Marmottini Maurizio RicciCarlo Rossi 《Microporous and mesoporous materials》2012,147(1):343-349
The ordered mesoporous silica material MCM-41 was used to prepare a novel drug delivery system (DDS) for oral administration of the diuretic furosemide (FURO), labeled in class IV of the Biopharmaceutics Classification System (BCS). This drug is characterized by both low solubility and permeability and its absorption window is the stomach and the proximal small intestine. Thus, the aim of this work was the development of an immediate formulation that could improve the drug release in its preferential absorptive regions.Three inclusion products MCM-41-FURO-E/D, MCM-41-FURO-S and MCM-41-FURO-E have been prepared in three different ways in order to find the best preparation conditions. They were characterized by XRPD, DSC, FT-IR, TGA and B.E.T. and then the inclusion products displaying the best characteristics were submitted to in vitro studies. They evidenced that the examined inclusion products displayed FURO dissolution enhancement, followed by a complete release within 90 min. Moreover, physical stability studies revealed that MCM-41 is able to stabilize the drug preventing it from re-crystallization. At last, as FURO is light sensitive, the effect of MCM-41 on drug photochemical stability was also investigated and the results indicated the protective action exerted by the matrix. 相似文献
95.
Andreea E. Pop Violeta Popescu Adrian Dinescu Medina N. Batin 《Materials Science-Poland》2013,31(3):318-324
Copper sulfide (Cu x S) films deposited on polypropylene substrate were obtained by chemical bath deposition (CBD) method. The influence of the deposition time on the morphology of Cu x S films was studied by means of scanning electron microscopy. We have found that the average particles dimension increased from 37 to 49 nm with the increase of deposition time from 20 to 30 minutes. The study of optical properties of the copper sulfide films was carried out based on optical transmission spectra recorded in the 400–1000 nm wavelength range. The optical constants, such as refractive index, extinction coefficient and dielectric constant as well as electrical and optical conductivity of Cu x S films were calculated. The obtained values are in accordance with the ones reported in the literature:We have shown that both, morphological and optical properties of Cu x S films are strongly affected by the deposition time. 相似文献
96.
Application of multi‐block analysis and mixture design with process variable for development of chocolate cake containing yacon (Smallanthus sonchifolius) and maca (Lepidium meyenii) 下载免费PDF全文
97.
Cinnamon intake reduces serum T3 level and modulates tissue‐specific expression of thyroid hormone receptor and target genes in rats 下载免费PDF全文
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Cokley Kevin O.; Tran Kimberly; Hall-Clark Brittany; Chapman Collette; Bessa Luana; Finley Angela; Martinez Michael 《Canadian Metallurgical Quarterly》2011,4(3):162
Reports an error in Predicting student attitudes about racial diversity and gender equity by Kevin O. Cokley, Kimberly Tran, Brittany Hall-Clark, Collette Chapman, Luana Bessa, Angela Finley and Michael Martinez (Journal of Diversity in Higher Education, 2010[Sep], Vol 3[3], 187-199). There are two errors in Table 2 under the RWA heading and the Cog-gender heading. The necessary changes are provided in the erratum. (The following abstract of the original article appeared in record 2010-18201-006.) Factors related to attitudes about racial diversity and gender equity were examined in an ethnically diverse sample of 432 college students (167 European Americans, 83 African Americans, 81 Asian Americans, and 82 Hispanic Americans). In addition to variables of self-interest (i.e., ethnicity, gender, and political views), social ideology (i.e., social dominance orientation, right-wing authoritarianism) and personality traits (openness to experience) were uniquely predictive of attitudes about racial diversity and gender equity. Hierarchical regressions revealed that social dominance orientation most strongly predicted racial attitudes, while right-wing authoritarianism most strongly predicted gender attitudes. Implications for diversity education efforts related to prejudice reduction are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
100.