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961.
Maria V. Encinas Eduardo Lissi Claudio Vergara 《Photochemistry and photobiology》2013,89(6):1399-1405
Valdecoxib addition quenches the intrinsic human serum albumin (HSA) fluorescence. This allows an evaluation of the drug–protein association. However, both the number of binding sites and their affinity for the drug depend upon the methodology employed for their evaluation and the employed protein concentration. In this work, we measured the effect of valdecoxib on HSA fluorescence yield over a wide range of experimental conditions and discuss the validity of the binding parameters derived from the different data treatments: Stern–Volmer, Scatchard, double logarithmic, quadratic equation, Benesi–Hilderand, and Encinas–Lissi. It is proposed that a combination of Encinas–Lissi and Scatchard treatments of the data renders the most reliable results. From these data, it is concluded that HSA presents three high‐affinity binding sites for valdecoxib (Kas = 4.5 × 104 m ?1) and several secondary sites of smaller activity. 相似文献
962.
Mauricio Gomes Constantino Paulo Marcos Donate Daniel Frederico Tecia Vieira Carvalho Luiz Eduardo Cardoso Julio Zukerman-Schpector 《合成通讯》2013,43(18):3327-3340
An eight-step synthesis of the cyclopentane keto-alcohol 2, which has previously been converted in one step into the carotenoid pigment capsorubin (1), is described. The key step in our synthesis is a stereospecific epoxide rearrangement with ring contraction, thus producing the cyclopentane ring from an epoxide of a cyclohexene. 相似文献
963.
Sara Silva Eduardo M. Costa Hlder Oliveira Vitor De Freitas Rui M. Morais Conceio Calhau Manuela Pintado 《Molecules (Basel, Switzerland)》2022,27(20)
Several arguments have been made to substantiate the need for natural antimicrobials for the food industry. With blueberry extracts, the most compelling are both their healthy connotation and the possibility of obtaining a multipurpose solution that can be an antioxidant, colorant, and antimicrobial. From an antimicrobial perspective, as blueberry/anthocyanin-rich extracts have been associated with a capacity to inhibit harmful bacteria while causing little to no inhibition on potential probiotic microorganisms, the study of potential benefits that come from synergies between the extract and probiotics may be of particular interest. Therefore, the present work aimed to evaluate the effect of an anthocyanin-rich extract on the adhesion of five different probiotics as well as their effect on the probiotics’ capacity to compete with or block pathogen adhesion to a mucin/BSA-treated surface. The results showed that, despite some loss of probiotic adhesion, the combined presence of extract and probiotic is more effective in reducing the overall amount of adhered viable pathogen cells than the PROBIOTIC alone, regardless of the probiotic/pathogen system considered. Furthermore, in some instances, the combination of the extract with Bifidobacterium animalis Bo allowed for almost complete inhibition of pathogen adhesion. 相似文献
964.
In this paper, we study solar magnetic activity by means of a complex network approach. A complex network was built based on information on the space and time evolution of sunspots provided by image recognition algorithms on solar magnetograms taken during the complete 23rd solar cycle. Both directed and undirected networks were built, and various measures such as degree distributions, clustering coefficient, average shortest path, various centrality measures, and Gini coefficients calculated for all them. We find that certain measures are correlated with solar activity and others are anticorrelated, while several measures are essentially constant along the solar cycle. Thus, we show that complex network analysis can yield useful information on the evolution of solar activity and reveal universal features valid at any stage of the solar cycle; the implications of this research for the prediction of solar maxima are discussed as well. 相似文献
965.
Ruy Luiz Milidiú Eduardo Sany Laber Artur Alves Pessoa 《Journal of Algorithms in Cognition, Informatics and Logic》1999,32(2):195
An important issue related to coding schemes is their compression loss. A simple measure ε of the compression loss due to a coding scheme different than Huffman coding is defined by ε = AC − AH where AH is the average code length of a static Huffman encoding and AC is the average code length of an encoding based on the compression scheme C. When the scheme C is the FGK algorithm, Vitter conjectured that ε ≤ K for some real constant K. Here, we use an amortized analysis to prove this conjecture. We show that ε < 2. Furthermore, we show through an example that our bound is asymptotically tight. This result explains the good performance of FGK that many authors have observed through practical experiments. 相似文献
966.
Eduardo Corts Corts Raúl Salazar Franco Olivia García Mellado 《Journal of heterocyclic chemistry》2001,38(3):663-669
A series of twelve new 2‐[(o‐ and p‐substituted)aminophenyl]‐3H‐5‐[(o‐ and p‐substituted)phenyl]‐7‐chloro‐1,4‐benzodiazepines, which have possible pharmacological properties has been obtained. The synthesis was carried out following six steps. The structure of all products was corroborated by ir, 1H nmr, 13C nmr and ms. In addition for the compound 2‐(o‐chloroaminophenyl)‐3H‐5‐(o‐fluorophenyl)‐7‐chloro‐1,4‐benzodiazepine 7, its structure was confirmed by X‐ray diffraction. 相似文献
967.
968.
969.
Pedro Álvarez‐Boo José S. Casas Eduardo E. Castellano M. Delfina Couce Rosa Farto Eduardo Freijanes José Sordo 《应用有机金属化学》2007,21(1):49-53
Reaction of 3‐(2‐methoxyphenyl)‐2‐sulfanylpropenoic acid [H2(o‐mpspa)] with SnPh3OH in the presence of di‐isopropylamine resulted in the formation of the complex [HQ][SnPh3(o‐mpspa)] (where HQ = di‐isopropylammonium cation and o‐mpspa = 3‐(2‐methoxyphenyl)‐2‐sulfanylpropenoato), which was characterized by mass spectrometry and vibrational spectroscopy, as well as by 1H, 13C and 119Sn NMR spectroscopy. The single‐crystal X‐ray structural analysis of the new complex shows a trigonal‐bipyramidal coordination geometry around the Sn atom where o‐mpspa behaves as a bidentate chelating ligand. Dimeric units arise from the existence of N? H…O hydrogen bonds between the NH2 group of the di‐isopropylammonium cation and the oxygen atoms of the two neighbouring carboxylato groups. The bacteriostatic activity of the complex is also reported. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
970.