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81.
Changes in actin and tubulin expression in osteogenic cells cultured on bioactive glass‐based surfaces 下载免费PDF全文
Carolina Scanavez Martins Emanuela Prado Ferraz Larissa Moreira Spinola De Castro‐Raucci Lucas Novaes Teixeira William Marcatti Amarú Maximiano Adalberto Luiz Rosa Paulo Tambasco De Oliveira 《Microscopy research and technique》2015,78(11):1046-1053
The present study evaluated whether the changes in the labeling pattern of cytoskeletal proteins in osteogenic cells cultured on bioactive glass‐based materials are due to altered mRNA and protein levels. Primary rat‐derived osteogenic cells were plated on Bioglass® 45S5, Biosilicate®, and borosilicate (bioinert control). The following parameters were assayed: (i) qualitative epifluorescence analysis of actin and tubulin; (ii) quantitative mRNA and protein expression for actin and tubulin by real‐time PCR and ELISA, respectively, and (iii) qualitative analysis of cell morphology by scanning electron microscopy (SEM). At days 3 and 7, the cells grown on borosilicate showed typical actin and tubulin labeling patterns, whereas those on the bioactive materials showed roundish areas devoid of fluorescence signals. The cultures grown on bioactive materials showed significant changes in actin and tubulin mRNA expression that were not reflected in the corresponding protein levels. A positive correlation between the mRNA and protein as well as an association between epifluorescence imaging and quantitative data were only detected for the borosilicate. SEM imaging of the cultures on the bioactive surfaces revealed cells partly or totally coated with material aggregates, whose characteristics resembled the substrate topography. The culturing of osteogenic cells on Bioglass® 45S5 and Biosilicate® affect actin and tubulin mRNA expression but not the corresponding protein levels. Changes in the labeling pattern of these proteins should then be attributed, at least in part, to the presence of a physical barrier on the cell surface as a result of the material surface reactions, thus limiting fluorescence signals. Microsc. Res. Tech. 78:1046–1053, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
82.
This paper investigates the removal of formic acid by unacclimated biomass from a municipal activated sludge wastewater treatment plant. The biomass was initially able to remove formic acid, but its removal rate and Oxygen Uptake Rate (OUR) decreased with time, until formic acid removal stopped before the formic acid had been exhausted. Formaldehyde was removed in a similar way, whereas the same biomass was simultaneously able to grow and store PHAs when acetic acid was used as substrate.Batch tests with glycine and 13C NMR analysis were performed, showing that unacclimated biomass was not able to synthesize all the metabolic intermediates from formic acid alone. At least glycine needed to be externally supplemented, in order to activate the serine synthesis pathway. A small amount of formic acid removal in the absence of growth was also possible through formaldehyde formation and its further conversion to formalin (1,2-formaldehyde dimer), whereas no PHAs were formed. 相似文献
83.
Duarte CD Greferath R Nicolau C Lehn JM 《Chembiochem : a European journal of chemical biology》2010,11(18):2543-2548
myo‐Inositol trispyrophosphate (ITPP), a novel membrane‐permeant allosteric effector of hemoglobin (Hb), enhances the regulated oxygen release capacity of red blood cells, thus counteracting the effects of hypoxia in diseases such as cancer and cardiovascular ailments. ITPP‐induced shifting of the oxygen–hemoglobin equilibrium curve in red blood cells (RBCs) was inhibited by DIDS and NAP‐taurine, indicating that band 3 protein, an anion transporter mainly localized on the RBC membrane, allows ITPP entry into RBCs. The maximum intracellular concentration of ITPP, determined by ion chromatography, was 5.5×10?3 M , whereas a drop in concentration to the limit of detection was observed in NAP‐taurine‐treated RBCs. The dissociation constant of ITPP binding to RBC ghosts was found to be 1.72×10?5 M . All data obtained indicate that ITPP uptake is mediated by band 3 protein and is thus highly tissue‐selective towards RBCs, a feature of major importance for its potential therapeutic use. 相似文献
84.
85.
The use of bovine rumen protein (raw and extruded) as a replacement for extruded soy protein concentrate in three meat products (pork sausage, chicken hamburger, and kibbe) was investigated. Similarity between rumen and soy protein meat products was assessed using triangle tests and sensory acceptability evaluated by consumer panelists using a nine-point hedonic scale. The addition of raw rumen protein was detected in all meat product types tested, while extruded rumen protein was only detected in kibbe. The addition of raw rumen protein decreased the acceptability of pork sausage aroma and flavor, but improved kibbe appearance, texture and overall acceptability. The addition of extruded rumen protein reduced the acceptability of chicken hamburger texture, but improved pork sausage flavor. Replacement of soy protein by bovine rumen protein is feasible based upon sensory results, but depended upon its form and the type of meat product to which it was added. 相似文献
86.
Carolina Griebeler Gianluca Tondi Thomas Schnabel Carmen Iglesias Sergio Ruiz 《Holz als Roh- und Werkstoff》2018,76(5):1495-1504
A new method that consists of combining wood pre-grading by surface colour followed by the application of homogeneity thermal treatments is proposed to reduce the surface colour variability of the thermally modified blue gum wood. To identify the conditions of the homogeneity thermal treatment for two pre-graded groups with different initial surface colours (pinkish and yellowish), the effects of applying 25 different thermal treatment intensities to such groups were analysed. The effects of this method on mass loss and volumetric swelling were also analysed. Results show that an optical pre-grading of the wood samples and treatments under different conditions can reduce the colour variability of the blue gum wood samples, as well as the volumetric swelling. Mass loss was not homogenised after the treatment, but the difference of masses between the two groups was similar to their untreated state. The application of this new methodology may be of interest for the sawn timber industry to bring more uniform boards on the markets and to promote Eucalyptus globulus as a price-competitive and sustainable alternative timber. 相似文献
87.
J. García-Nieto E. Alba A. Carolina Olivera 《Engineering Applications of Artificial Intelligence》2012,25(2):274-283
Congestion, pollution, security, parking, noise, and many other problems derived from vehicular traffic are present every day in most cities around the world. The growing number of traffic lights that control the vehicular flow requires a complex scheduling, and hence, automatic systems are indispensable nowadays for optimally tackling this task. In this work, we propose a Swarm Intelligence approach to find successful cycle programs of traffic lights. Using a microscopic traffic simulator, the solutions obtained by our algorithm are evaluated in the context of two large and heterogeneous metropolitan areas located in the cities of Málaga and Sevilla (in Spain). In comparison with cycle programs predefined by experts (close to real ones), our proposal obtains significant profits in terms of two main indicators: the number of vehicles that reach their destinations on time and the global trip time. 相似文献
88.
Felipe C. da Silva Carolina Rodrigues da Fonseca Severino Matias de Alencar Marcelo Thomazini Julio C. de Carvalho Balieiro Paola Pittia Carmen Sílvia Favaro-Trindade 《Food and Bioproducts Processing》2013,91(1):28-36
The aim of this work was to obtain propolis in a powder, alcohol-free, water-dispersed and shelf-stable form. Propolis extract was spray-dried using gum Arabic and octenyl succinic anhydride (OSA) starch as carriers in two different weight ratios (1:4 and 1:6). Spray-dried propolis samples were evaluated for morphology, moisture, water activity, water dispersibility, hygroscopicity, particle size, particle distribution, entrapping efficiency, stability, isotherms and antioxidant properties. The spray-drying process produced round particles with sizes ranging from 15 to 24 μm. This process preserved the antioxidant activity of propolis and also allowed propolis to be obtained in a powder form, which was stable during storage at room temperature, had low hygroscopicity and was highly dispersible in cold water. The application of this technology could increase the use of propolis in various industrial applications, such as an antimicrobial and as an antioxidant in food. 相似文献
89.
de Weerth Carolina; van Geert Paul; Hoijtink Herbert 《Canadian Metallurgical Quarterly》1999,35(4):1102
Longitudinal observational data of infant crying, fretting/fussing, and smiling and the time spent in physical contact with the mother were used in a study on behavioral variability. The infants were followed weekly for a 15-month period. Evidence was found of an important intraindividual variability in the studied behaviors, specifically between the ages of 0 and 5 months, 5 and 10 months, but not between 10 and 15 months. Results are discussed and analyzed in the light of earlier literature. The possible functions and the factors underlying variability in development as well as its methodological implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
The acid-catalyzed reaction of glycerol with acetone was studied in the presence of impurities that might be present in the crude glycerin of biodiesel production. These are mainly methanol, water and sodium chloride, in different amounts. The results indicated that methanol has minor effect on the glycerol conversion, whereas the concomitant addition of water and sodium chloride produces a drastic decrease of the conversion. The nature of the acid catalyst also affects the conversion in the presence of impurities. Amberlyst-15™ acid resin is more sensible to the water content than zeolite Beta. The results of the glycerol adulteration with different contaminants were compared with the reaction using a crude glycerin from a Brazilian biodiesel industrial plant. 相似文献