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51.
Marcelo Medeiros Pinheiro Rozana Mesquita Ciconelli Gabriela Villaça Chaves Luana Aquino Claudia Ridel Juzwiak Patrícia de Souza Genaro Marcos Bosi Ferraz 《Nutrition journal》2011,10(1):39
Background
Antioxidant nutrient intake and the lesser formation of free radicals seem to contribute to chronic diseases. The aim of the present study was to evaluate the intake profile of the main dietary antioxidants in a representative sample of the adult Brazilian population and discuss the main consequences of a low intake of these micronutrients on overall health. 相似文献52.
Flávia Mesquita Cabrini Mathilde Champeau Marcelo Ganzarolli de Oliveira 《应用聚合物科学杂志》2020,137(36):49056
Changing the pore morphology of hydrogels can be an effective strategy to modulate their drug release profiles. Herein, Pluronic F127 was used to change the three-dimensional pore morphology of crosslinked poly(N-isopropylacrylamide-co-acrylic acid) (P[NIPAm-co-AAc]) hydrogels. F127 reduced the pore diameters from 20 ± 4 to 2.9 ± 0.4 μm and from 11 ± 1 to 1.4 ± 0.4 μm in hydrogels synthesized at 8 and 30°C, respectively. Small-angle X-ray scattering indicates that the segregation of the F127 during the polymerization process induces F127 phase transitions from unimers (at 8°C) or cubic-packed micelles (at 30°C) to a lamellar structure. P(NIPAm-co-AAc) hydrogels charged with S-nitrosoglutathione (GSNO), released nitric oxide (NO) spontaneously during hydration. The decrease in the pore diameter led to a twofold to threefold increase in the rate of water absorption and a fourfold to sixfold increase in the rate of NO release of the hydrogels. F127 can be used to change the pore morphology of P(NIPAm-co-AAc) hydrogels, with concomitant changes in their rate of hydration and NO release from GSNO, opening a new perspective for their use in topical NO delivery. 相似文献
53.
Viviane?L.?Pardo Cássia?A.?M.?Fagundes Sergiane?S.?Caldas Márcia?H.?Kurz Rosilene?M.?Clementin Marcelo?G.?M.?D’Oca Ednei?G.?PrimelEmail author 《Journal of the American Oil Chemists' Society》2012,89(4):631-637
The aim of this study was to develop and validate a method for the analysis of fatty acid methyl ester (FAMEs) content in
tung biodiesel and blends with soybean biodiesel. The limits of detection (LOD) and quantification (LOQ), linearity, robustness,
accuracy and precision were evaluated by using gas chromatography with mass spectrometry detection and impact electron ionization.
The analytical curves showed correlation coefficients values higher than 0.99. The LOD and LOQ were 0.78 and 2.5 mg L−1 for all FAMEs, respectively. The values of accuracy were between 86 and 117%, with relative standard deviation lower than
8%. The method was applied to tung biodiesel and tung and soybean biodiesel blends in the following proportions: 15:85, 20:80,
25:75 (%v/v). All of them showed good performance. Since the method was also applied to soybean biodiesel, the efficiency
of the method for the analysis of both pure tung biodiesel and blends with different raw materials was confirmed and the robustness
of the method was evidenced. 相似文献
54.
Dantas-Barbosa C de Macedo Brigido M Maranhao AQ 《International journal of molecular sciences》2012,13(5):5420-5440
Since the advent of phage display technology, dating back to 1985, antibody libraries displayed on filamentous phage surfaces have been used to identify specific binders for many different purposes, including the recognition of tumors. Phage display represents a high-throughput technique for screening billions of random fusion antibodies against virtually any target on the surface or inside cancer cells, or even soluble markers found in patient serum. Many phage display derived binders targeting important tumor markers have been identified. Selection directed to tumoral cells' surfaces lead to the identification of unknown tumoral markers. Also the improvement of methods that require smaller amounts of cells has opened the possibility to use this approach on patient samples. Robust techniques combining an antibody library displayed on the phage surface and protein microarray allowed the identification of auto antibodies recognized by patient sera. Many Ab molecules directly or indirectly targeting angiogenesis have been identified, and one of them, ramucirumab, has been tested in 27 phase I-III clinical trials in a broad array of cancers. Examples of such antibodies will be discussed here with emphasis on those used as probes for molecular imaging and other clinical trials. 相似文献
55.
Juliana Mendes de Oliveira Iara Alves Anes Jorge Luís Coleti Denise Crocce Romano Espinosa Marcelo Siqueira de Carvalho Jorge Alberto Soares Tenório 《加拿大化工杂志》2023,101(4):1743-1761
Niobium (Nb) and Tantalum (Ta) are used to increase materials' mechanical resistance and produce lighter alloys. Worldwide Nb production reached 78 000 t in 2020. The reduced ore offer justifies the recycling of these metals from tin slag, contributing to the circular economy. Nb2O5 and Ta2O5 extraction either from the primary source or the tin slag is an industrial challenge. Nb and Ta dissolution processes already implemented are fluoride leaching, sulphuric leaching, alkaline leaching, and alkaline roasting. The fluoride process raises environmental concerns about waste control. The sulphuric method can be managed to have higher Nb and Ta extraction in a less aggressive process, if some changes are implemented, such as increasing the number of extraction steps, decreasing the pulp density, or increasing the temperature; however, the efficiency of this methodology must be tested for tin slag. The alkaline method seems to be more selective to Nb and Ta by reactants and temperature control. Despite those well-established Nb and Ta treatments, they must be adapted to recover Nb and Ta from slag. The slag has low Nb and Ta content, while high Si and Ca concentrations exist in the matrix. This paper brings the main methods used to extract the Nb and Ta from the primary resources and an overview of Nb and Ta recovery from the slag. This investigation comes as a tool to guide the development of new methods to recover Nb and Ta from low-grade sources such as tin slag. 相似文献
56.
Marta K. Schütz Natália F. Lopes Angélica Cenci João Marcelo M. Ketzer Sandra Einloft Jeane Dullius Rosane Ligabue 《化学工程与技术》2018,41(3):573-579
Carbon dioxide (CO2) gas is the main contributor to climate change. CO2 storage in underground brines and oil‐field brines by mineral trapping has been considered as a promising alternative in order to reduce CO2 emissions. However, permanent storage of CO2 in stable carbonate minerals is greatly dependent on brine pH, being favored over an alkaline pH. The effect of alkaline additives (NaOH, KOH, CaO) and buffer solutions (NaHCO3/NaOH, Na2HPO4/NaOH, NH4Cl/NH4OH) on the mineral trapping of CO2 under mild conditions using a synthetic brine is investigated. The results indicate that both NaOH+NH4Cl/NH4OH and KOH+NH4Cl/NH4OH mixtures promote precipitation mainly of calcium carbonate (CaCO3). 相似文献
57.
FAME Production and Fatty Acid Profiles from Moist Chlorella sp. and Nannochloropsis oculata Biomass 下载免费PDF全文
Rui C. M. Alves Sobrinho Laércio Vauchinski Renata Rodrigues de Moura Ednei G. Primel Paulo C. V. Abreu Marcelo G. Montes D’Oca 《Journal of the American Oil Chemists' Society》2015,92(3):423-430
In the present study, we investigated the production of fatty acid methyl esters (FAME) from moist Chlorella sp. and Nannochloropsis oculata biomass using a hydrolysis–esterification process. Additionally, we evaluated for the first time the fatty acid profile before and after this process. Hydrolysis of the lipid fraction was performed on a moist biomass in the presence of differing amounts of an acid catalyst in both 50 and 100 % w/w water relative to the biomass. The esterification of the crude extracts of the free fatty acids (FFA) was then investigated. The experiments show that in the presence of 50 % w/w water relative to the biomass, the hydrolysis–esterification process results in higher FFA and FAME yields. The analysis of the fatty ester profiles did not reveal any degradation of the FFA from the microalgae biomass under the hydrolysis–esterification conditions. The results were compared with both extraction–transesterification and direct transesterification processes using dry biomass. The extraction–transesterification and hydrolysis–esterification processes resulted in similar FAME yields and similar profiles of the fatty esters from dry and moist biomass materials, respectively. 相似文献
58.
Software for Simulation of Second‐Generation Ethanol Production by a Simultaneous Saccharification and Fermentation Process 下载免费PDF全文
Environmental impacts associated with the consumption of fossil fuels and the need to generate power through renewable resources demands the usage of alternative materials. The objective is the production of clean energy from materials like lignocellulosic biomass to produce second‐generation (2G) ethanol. A software in the Matlab program is elaborated to simulate the simultaneous saccharification and fermentation (SSF) process of lignocellulosic biomass for the 2G ethanol production in batch reactors. Studying the effects of the process variables, it was found that the higher interference is caused by cellulose concentration. Higher concentrations of the product in batch processes are obtained with the maximum cellulose concentrations, cells, and enzyme. 相似文献
59.
A Synthetic MUC1 Glycopeptide Bearing βGalNAc‐Thr as a Tn Antigen Isomer Induces the Production of Antibodies against Tumor Cells 下载免费PDF全文
Dr. Vanessa Leiria Campo Thalita B. Riul Leandro Oliveira Bortot Maristela B. Martins‐Teixeira Marcelo Fiori Marchiori Emanuela Iaccarino Dr. Menotti Ruvo Prof. Dr. Marcelo Dias‐Baruffi Prof. Dr. Ivone Carvalho 《Chembiochem : a European journal of chemical biology》2017,18(6):527-538
This study presents the synthesis of the novel protected O‐glycosylated amino acid derivatives 1 and 2 , containing βGalNAc‐SerOBn and βGalNAc‐ThrOBn units, respectively, as mimetics of the natural Tn antigen (αGalNAc‐Ser/Thr), along with the solid‐phase assembly of the glycopeptides NHAcSer‐Ala‐Pro‐Asp‐Thr[αGalNAc]‐Arg‐Pro‐Ala‐Pro‐Gly‐BSA ( 3 ‐BSA) and NHAcSer‐Ala‐Pro‐Asp‐Thr[βGalNAc]‐Arg‐Pro‐Ala‐Pro‐Gly‐BSA ( 4 ‐BSA), bearing αGalNAc‐Thr or βGalNAc‐Thr units, respectively, as mimetics of MUC1 tumor mucin glycoproteins. According to ELISA tests, immunizations of mice with βGalNAc‐glycopeptide 4 ‐BSA induced higher sera titers (1:320 000) than immunizations with αGalNAc‐glycopeptide 3 ‐BSA (1:40 000). Likewise, flow cytometry assays showed higher capacity of the obtained anti‐glycopeptide 4 ‐BSA antibodies to recognize MCF‐7 tumor cells. Cross‐recognition between immunopurified anti‐βGalNAc antibodies and αGalNAc‐glycopeptide and vice versa was also verified. Lastly, molecular dynamics simulations and surface plasmon resonance (SPR) showed that βGalNAc‐glycopeptide 4 can interact with a model antitumor monoclonal antibody (SM3). Taken together, these data highlight the improved immunogenicity of the unnatural glycopeptide 4 ‐BSA, bearing βGalNAc‐Thr as Tn antigen isomer. 相似文献
60.
Synthesis and characterization of a new biobased poly(urethane‐ester) from ricinoleic acid and its use as biopolymeric matrix for magnetic nanocomposites 下载免费PDF全文