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51.
Inside Cover: Pro‐oxidant and Antioxidant Effects in Photodynamic Therapy: Cells Recognise that Not All Exogenous ROS Are Alike (ChemBioChem 9/2016) 下载免费PDF全文
52.
Viviane Muniz da Silva Fragoso Carla Patrícia de Morais Coura Luanda Yanaan Hoppe Marília Amável Gomes Soares Dilson Silva Celia Martins Cortez 《International journal of molecular sciences》2016,17(1)
The aim of this work was to study the interaction of sulpiride with human serum albumin (HSA) and bovine serum albumin (BSA) through the fluorescence quenching technique. As sulpiride molecules emit fluorescence, we have developed a simple mathematical model to discriminate the quencher fluorescence from the albumin fluorescence in the solution where they interact. Sulpiride is an antipsychotic used in the treatment of several psychiatric disorders. We selectively excited the fluorescence of tryptophan residues with 290 nm wavelength and observed the quenching by titrating HSA and BSA solutions with sulpiride. Stern-Volmer graphs were plotted and quenching constants were estimated. Results showed that sulpiride form complexes with both albumins. Estimated association constants for the interaction sulpiride–HSA were 2.20 (±0.08) × 104 M−1, at 37 °C, and 5.46 (±0.20) × 104 M−1, at 25 °C. Those for the interaction sulpiride-BSA are 0.44 (±0.01) × 104 M−1, at 37 °C and 2.17 (±0.04) × 104 M−1, at 25 °C. The quenching intensity of BSA, which contains two tryptophan residues in the peptide chain, was found to be higher than that of HSA, what suggests that the primary binding site for sulpiride in albumin should be located next to the sub domain IB of the protein structure. 相似文献
53.
54.
F. M. T. Mendes C. A. Perez R. R. Soares F. B. Noronha M. Schmal 《Catalysis Today》2003,78(1-4):449-458
Ammonium oxalate complex of niobium was investigated as an aqueous precursor for the preparation of x% Nb2O5/Al2O3 (x=5, 10, 20 and 30 wt.%) samples. Catalysts with the same Nb2O5 contents were also prepared from the traditional niobium oxalate/oxalic acid aqueous solution. The catalysts were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), temperature-programmed reduction (TPR), infrared spectroscopy of chemisorbed pyridine and X-ray photoelectron spectroscopy (XPS). A comparison with the preparation method using the niobium oxalate salt was performed. The results showed that the niobium precursor influence the species growing leading to phases with different reducibility. The XPS revealed the presence of multilayers of niobium oxide on the Nb2O5/Al2O3 samples prepared by using niobium ammonium oxalate complex, while the ones obtained from niobium oxalate led to Nb2O5 particles islands. The addition of niobium oxide decreased the fraction of Lewis acid sites and increased the fraction of Brønsted acid sites, independent of the precursor salt. However, the creation of BAS was more pronounced on the Nb2O5/Al2O3 samples prepared from niobium oxalate. 相似文献
55.
Nathália de Andrade Neves Lílian de Araújo Pantoja Alexandre Soares dos Santos 《European Food Research and Technology》2014,238(1):79-84
This study examined the thermovinification technique using yeasts immobilized on calcium alginate for microvinification of the Cabernet Sauvignon and Pinot Noir grape varieties grown in Diamantina, Minas Gerais, Brazil. The wines obtained by thermovinification were characterized by their chemical and sensory aspects. The varietal wines from Cabernet Sauvignon and Pinot Noir had an alcohol content of 9.3 and 10.9 % (v/v), respectively. The total acidity, volatile acidity and the alcohol/reduced dry extract ratio were consistent with the Brazilian standards established for identity and quality of wines. There was a significant reduction in the levels of anthocyanins, flavonoids and total phenolic compounds after aging in the bottle. The sensory evaluation presented an acceptability exceeding 60 % for both wines. 相似文献
56.
Comparison of vacuum impregnation and soaking techniques for addition of the probiotic Lactobacillus acidophilus to minimally processed melon 下载免费PDF全文
Patrícia Martins de Oliveira Afonso Mota Ramos Eliane Maurício Furtado Martins Érica Nascif Rufino Vieira Ariana de Souza Soares Marcel Cardoso de Noronha 《International Journal of Food Science & Technology》2017,52(12):2547-2554
This study aimed to evaluate the vacuum impregnation (VI) and soaking methods in the addition of Lactobacillus acidophilusLA‐3 to minimally processed melon (MPM). The melons were washed, sanitised in chlorine solution (200 mg L?1), peeled and cutted into cubes. Lactobacillus acidophilusLA‐3 (1.4 × 1010 CFU g?1) were added to the MPM through both techniques. The L. acidophilusLA‐3 count in MPM was similar to those commonly found in dairy products having probiotic claim, but VI was more efficient than soaking in maintaining the viability (8.61 and 7.98 Log CFU g?1, respectively). The pH, acidity and soluble solids were not affected by probiotic culture and the incorporation technique; however, the VI affected the firmness of fruit. The MPM was within Brazilian standards for their microbiological characteristics. MPM may be used as a carrier of probiotic bacteria, being one more alternative for individuals who consume probiotic products. 相似文献
57.
T. Diana L v. A. de Macedo‐Soares Ph.D. Paulo Jacinto Pastor‐Braga B.Sc. 《Information Technology for Development》2013,19(4):453-485
Abstract This article gives an account of the results of a case study undertaken at a pioneer and particularly prominent firm in the Brazilian computer industry: COBRA — Computadores e Sistemas Brasileiros SA. The study is part of a research project1 whose main goal is the identification of viable organizational and technological options that could enhance the performance of firms in the Brazilian electro‐electronics industry. Among the more important findings, it was observed that the firm has the potential to evolve to a more flexible structure, in keeping with the new requirements of the probable future market scenarios within its sector. Everything indicated, however, that the main constraining factors for bringing about such a structure were connected with the firm's culture and beliefs and with the indirect influence of the National Policy of Information Technology upon these. An hypothesis was put forward for an organizational model, and the necessary supportive computerized technology, which could be particularly appropriate in view of the impending deregulation, of the Brazilian computer industry. Also, in the scope of the current discussion on the restructuring of this industry in terms of a greater concentration, an alternative to the prevailing school of thought was proposed, and for whose success the organizational model at issue purports to be particularly relevant. 相似文献
58.
M. Adak C. Guedes Soares 《The International Journal of Advanced Manufacturing Technology》2014,71(1-4):699-710
Effects of three different plate boundary constraints on the residual stress field and deformation are investigated numerically during butt-joint welding. For the numerical solution of the heat transfer equations, the finite element method is used to predict the temperature profile as well as residual stress field due to three different plate boundary conditions. The distortion of the welded plate is modeled as a nonlinear problem in geometry and material, adopting a finite element solution based upon the thermo–elastic–plastic large deflection theory. High-strength shipbuilding steel AH36 with temperature-depending material properties and nonlinear stress–strain material properties (bilinear isotropic hardening option uses the von Mises yield criteria) are assumed for the numerical analysis. For verifying the results, the temperature profile is compared with the result obtained in a previous research. In the mechanical analysis, three different boundary conditions are applied. Effects of plate thickness, plate width, and mesh model on the residual stress with boundary constraint are studied. 相似文献
59.
Susane Moreira Machado Anderson Oliveira Lobo Ariel Bueno Loureiro Sapucahy Fernanda Roberta Marciano Evaldo Jose Corat Newton Soares da Silva 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1614-1617
For the first time, we show that Tritrichomonas foetus can adhere on superhydrophilic vertically aligned carbon nanotubes (VACNT) films. Scanning electron microscopy shows an unusual adhesion with a higher membrane filopodium projection in all directions, directly attached to superhydrophilic VACNT tips. 相似文献
60.
Thales Leandro Coutinho de Oliveira Rodrigo de Araújo Soares Roberta Hilsdorf Piccoli 《Meat science》2013
The antimicrobial effect of oregano (Origanum vulgare L.) and lemongrass (Cymbopogon citratus (DC.) Stapf.) essential oils (EOs) against Salmonella enterica serotype Enteritidis in in vitro experiments, and inoculated in ground bovine meat during refrigerated storage (4 ± 2 °C) for 6 days was evaluated. The Weibull model was tested to fit survival/inactivation bacterial curves (estimating of p and δ parameters). The minimum inhibitory concentration (MIC) value for both EOs on S. Enteritidis was 3.90 μl/ml. The EO concentrations applied in the ground beef were 3.90, 7.80 and 15.60 μl/g, based on MIC levels and possible activity reduction by food constituents. Both evaluated EOs in all tested levels, showed antimicrobial effects, with microbial populations reducing (p ≤ 0.05) along time storage. Evaluating fit-quality parameters (RSS and RSE) Weibull models are able to describe the inactivation curves of EOs against S. Enteritidis. The application of EOs in processed meats can be used to control pathogens during refrigerated shelf-life. 相似文献