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A. G. BezerraJr P. Cavassin T. N. Machado T. D. Woiski R. Caetano W. H. Schreiner 《Journal of nanoparticle research》2017,19(11):362
Bismuth nanoparticles produced by laser ablation synthesis in solution (LASiS) show localized surface plasmon resonances (LSPRs). The nanoparticles show surface-enhanced Raman scattering (SERS) activity for several tested amino acids. Optical absorption, dynamic light scattering (DLS), and transmission electron microscopy (TEM) as well as Raman scattering were used to characterize the samples. The search for new biocompatible nanoparticles for diagnostic purposes is important, and the demonstration that a semimetal is capable to act as a SERS active system opens new possibilities for molecular detection. 相似文献
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Paula Rossini Augusti Andria Quatrin Renius Mello Vivian Caetano Bochi Eliseu Rodrigues Inês D. Prazeres Ana Catarina Macedo Sheila Cristina Oliveira-Alves Tatiana Emanuelli Maria Rosrio Bronze Ana Teresa Serra 《Molecules (Basel, Switzerland)》2021,26(15)
Jaboticaba is a Brazilian native berry described as a rich source of phenolic compounds (PC) with health promoting effects. PC from jaboticaba peel powder (JPP) have low intestinal bio-accessibility and are catabolized by gut microbiota. However, the biological implication of PC-derived metabolites produced during JPP digestion remains unclear. This study aimed to evaluate the antiproliferative effects of colonic fermented JPP (FJPP) in a 3D model of colorectal cancer (CRC) composed by HT29 spheroids. JPP samples fermented with human feces during 0, 2, 8, 24 or 48 h were incubated (10,000 µg mL−1) with spheroids, and cell viability was assessed after 72 h. Chemometric analyses (cluster and principal component analyses) were used to identify the main compounds responsible for the bioactive effect. The antiproliferative effect of FJPP in the CRC 3D model was increased between 8 h and 24 h of incubation, and this effect was associated with HHDP-digalloylglucose isomer and dihydroxyphenyl-γ-valerolactone. At 48 h of fermentation, the antiproliferative effect of FJPP was negligible, indicating that the presence of urolithins did not improve the bioactivity of JPP. These findings provide relevant knowledge on the role of colonic microbiota fermentation to generate active phenolic metabolites from JPP with positive impact on CRC. 相似文献
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Bution ML Caetano FH Britto FB Tomaino Gomes GA Zara FJ 《Micron (Oxford, England : 1993)》2006,37(3):249-254
In this study we histologically and histochemically describe the ventriculus of Dolichoderus bispinosus. The epithelium consists of two basic cell types, highly basophilic generative cells, and digestive cells. The latter present several cytoplasmic vesicles, rich in acidic and neutral polysaccharides, and basic proteins. Also, these cells exhibit an apocrine secretion pattern. A mass of fibrous material is observed on the surface of the epithelium. Finally, we discuss the results obtained. 相似文献
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The structural, electronic, and thermodynamic properties of ammonia-borane complexes with varying amounts of hydrogen have been characterized by first principles calculations within density functional theory. The calculated structural parameters and thermodynamic functions (free energy, enthalpy and entropy) were found to be in good agreement with experimental and quantum chemistry data for the crystals, dimers, and molecules. The authors find that zero-point energies change several H2 release reactions from endothermic to exothermic. Both the ammonia-borane polymeric and borazine-cyclotriborazane cycles show a strong exothermic decomposition character (approximately -10 kcal/mol), implying that rehydrogenation may be difficult to moderate H2 pressures. Hydrogen bonding in these systems has been characterized and they find the N-H bond to be more covalent than the more ionic B-H bond. 相似文献
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This paper uses Mutual Information as an alternative variable selection method for quantitative structure-property relationships data. To evaluate the performance of this criterion, the enantioselectivity of 67 molecules, in three different chiral stationary phases, is modelled. Partial Least Squares together with three commonly used variable selection techniques was evaluated and then compared with the results obtained when using Mutual Information together with Support Vector Machines. The results show not only that variable selection is a necessary step in quantitative structure-property relationship modelling, but also that Mutual Information associated with Support Vector Machines is a valuable alternative to Partial Least Squares together with correlation between the explanatory and the response variables or Genetic Algorithms. This study also demonstrates that by producing models that use a rather small set of variables the interpretation can be also be improved. 相似文献
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R.G. Sarmento G.A. Mendes E.L. Albuquerque U.L. Fulco M.S. Vasconcelos O. Ujsághy V.N. Freire E.W.S. Caetano 《Physics letters. A》2012
The electronic specific heat spectra at constant volume (CV) of a long-range correlated extended ladder model, mimicking a DNA molecule, is theoretically analyzed for a stacked array of a double-stranded structure made up from the nucleotides guanine G, adenine A, cytosine C and thymine T . The role of the aperiodicity on CV is discussed, considering two different nucleotide arrangements with increasing disorder, namely the Fibonacci and the Rudin–Shapiro quasiperiodic structures. Comparisons are made for different values of the band fillings, considering also a finite segment of natural DNA, as part of the human chromosome Ch22. 相似文献