3,439 research outputs found

    Adsorption of proteins to thin-films of PDMS and its effect on the adhesion of human endothelial cells

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    This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine serum albumin) under different conditions. The information collected from the protein adsorption studies was then used to investigate the adhesion of human dermal microvascular endothelial cells. The results of these studies suggest that these films can be used to model the surface properties of microdevices fabricated with commercial PDMS. Moreover, the paper provides guidelines to efficiently attach cells in BioMEMS devices.Fil: Chumbimuni Torres, Karin Y.. The University of Texas at San Antonio; Estados UnidosFil: Coronado, Ramon E.. The University of Texas at San Antonio; Estados UnidosFil: Mfuh, Adelphe M.. The University of Texas at San Antonio; Estados UnidosFil: Castro Guerrero, Carlos. The University of Texas at San Antonio; Estados UnidosFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Negrete, George R.. The University of Texas at San Antonio; Estados UnidosFil: Bizios, Rena. The University of Texas at San Antonio; Estados UnidosFil: Garcia, Carlos D.. The University of Texas at San Antonio; Estados Unido

    Efecto de compuestos fenólicos presentes en extractos de plantas argentinas en el crecimiento miceliar del fitopatógeno Botrytis cinerea Pers

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    The polyphagous plant pathogen Botrytis cinerea has the ability of growing fast under several conditions, and producing grey moulds in different plant tissues. Because of its adaptive plasticity, resistant strains have made difficult their chemical control. Therefore, new strategies of management and the use of natural compounds could be important control alternatives. The aim of this work was to study the potential value of four Argentine native plant extracts and some of its phenolic compounds as biodrugs on B. cinerea. Aqueous plant extracts of Larrea divaricata, Prosopis strombulifera, Tessaria absinthioides and Schinus molle var. areira, were used. The capability to inhibit the mycelial growth was studied using either the crude plant extract or same its most important, detected phenolic compounds. Phenolic compounds were analyzed by Capillary Zone Electrophoresis (CZE) with UV detection, and then statistically analyzed by Principal Component Analysis to correlate them and their biological activity against the fungus. Prosopis strombulifera and T. absinthioides extracts did not inhibit mycelial growth while S. molle stimulated it. Larrea divaricata demonstrated inhibition above 50% at plant extracts concentrations of 100 mg/mL.Fil: Hapon, María Vanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Boiteux, Joana Jaqueline. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Fernández, M. A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Lucero, G.. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Silva, María Fernanda. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Pizzuolo, Pablo Humberto. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin

    Composição química, capacidade antioxidante e conteúdo polifenólico da farinha de alfarroba (Ceratonia siliqua L.) em relação à presença de semente e efeito de torrefação

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    Carob is the fruit of an evergreen tree (Ceratonia siliqua L.) cultivated in the Mediterranean area, where Portugal has a high-cultivated extent with relevant production and low prices. Carob is well known for its valuable locust bean gum. However, carob pods contain various relevant nutrients, including proteins, carbohydrates and fiber, and phytochemicals such as polyphenols, which position carob flour with great potential to be used as a functional ingredient. This study aimed to evaluate the impact of different roasting processes of carob flour (with and without seeds) on its nutritional composition and antioxidant activity. Seed presence led to a higher content of macronutrients in carob flour. The roasting processing affected the total content of polyphenols (TPC), determined by Folin-Ciocalteau, since the content at 150 ºC was twice of that obtained at 80 ºC, probably due to the formation of certain Maillard reaction products (MRPs), or certain phenolics that may degrade during roasting. The antioxidant activity is correlated with TPC, increasing when the flour was roasting at 150ºC. Regarding the total fiber content, a significant increase was observed in samples processed at 150 ºC. These findings confirm the importance of understanding the impact of processing on the nutritional value and bioactive properties of carob flours, to use them efficiently as a functional food ingredient.Alfarroba é um fruto de árvore perene (Ceratonia siliqua L.) cultivada na área mediterrânea, na qual Portugal compreende alta extensão de cultivo com produção relevante e baixo custo. Alfarroba é usualmente conhecida pela goma de alfarroba, contudo as vagens de alfarroba contêm variados nutrientes relevantes, incluindo proteínas, hidratos de carbono e fibra, e fitoquímicos tais como polifenóis, conferindo à farinha de alfarroba potencial para ser usada como ingrediente funcional. Este estudo focou-se na avaliação do impacto de diferentes processos de torrefação da farinha de alfarroba (com e sem semente) na sua composição nutricional e capacidade antioxidante. A presença de semente levou a alto conteúdo de macronutrientes na farinha de alfarroba. O processo de torrefação afetou o conteúdo total de polifenóis (CTP), determinado por FolinCiocalteau, uma vez que para 150 ºC o conteúdo obtido foi o dobro daquele obtido para 80 ºC, possivelmente devido à formação de certos produtos de reações Maillard (PRMs) ou certos fenóis que possam degradar durante a torrefação. A atividade antioxidante correlaciona-se com o CTP, aumento na farinha de alfarroba processada a 150 ºC. Relativamente ao conteúdo de fibras totais, observou-se um aumento significativo nas amostras processadas a 150 ºC. Os resultados obtidos comprovam a importância em analisar o impacto do processamento ao nível do valor nutricional e das propriedades bioativas da farinha de alfarroba, de forma a ser usada eficientemente como ingrediente funcional em alimentos.info:eu-repo/semantics/publishedVersio

    Genome sequences of triacylglycerol metabolism in Rhodococcus as a platform for comparative genomics

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    Bacteria belonging to the Rhodococcus genus are usually able to synthesize and accumulate variable amounts of triacylglycerols (TAG) from diverse carbon sources. Although some significant advances in the basic knowledge on TAG metabolism in rhodococci have been made, the fundamental understanding of this process and its regulation remains to be clarified. The abundantly available genomic information for several rhodococcal species provides the possibility for comparative genome analysis on the occurrence and distribution of key genes and pathways involved in TAG metabolism. Our bioinformatic analyses of available databases from six rhodococcal strains demonstrated that genes/enzymes for reactions related to TAG biosynthesis and degradation, and fatty acid β-oxidation are surprisingly abundant in rhodococcal genomes. Several genes/enzymes of glycerolipids and fatty acid metabolism are highly represented in the analyzed genomes. A number of previously undescribed, new putative genes for glycerolipid metabolism in rhodococci have been identified and the size of each family has been estimated

    Colloidal stability of gadolinium-doped ceria powder in aqueous and non-aqueous media

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    In this work the colloidal behaviour of Ce0.9Gd0.1O2-δ powder in aqueous and non-aqueous media (ethanol) is studied. Commercial powder was characterised by particle size distribution, specific surface area measurements, X-ray diffraction and scanning electron microscopy. Diluted suspensions were characterised by particle size distribution and zeta potential, using dynamic light scattering and laser Doppler velocimetry principles, respectively. The solubility of the powder in water as a function of pH was analysed by inductively coupled plasma atomic emission spectrometry. Colloidal stability was studied as a function of pH, type and concentration of dispersants (polyacrylic-based deflocculant in water and a phosphate ester in ethanol). The time stability of the suspensions was analysed by multiple light scattering. The most stable suspension was obtained with a phosphate ester content of 2.0wt% in ethanol. Finally, preliminary coatings have been obtained by dip coating using concentrated suspensions, which could be accessible to industrial scale so that they can be used as interlayers in solid oxide fuel cells. © 2012 Elsevier Ltd.We would like to thank grants PSE-120000-2008-0040 and MAT2009-14324-C02-01, financed by the Spanish Government (Ministerio de Ciencia e Innovación) and Feder Program of the European Community, and PI/116, financed by the Aragón Government.Peer Reviewe

    Building public-private partnerships for agricultural innovation:

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    Public-private partnerships are a new way of carrying out research and development (R&D) in Latin America's agricultural sector. These partnerships spur innovation for agricultural development and have various advantages over other institutional arrangements fostering R&D. This report summarizes the experiences of a research project that analyzed 125 public-private research partnerships (PPPs) in 12 Latin American countries. The analysis indicates that several types of partnerships have emerged in response to the various needs of the different partners. Nevertheless, public-private partnerships are not always the most appropriate mechanism by which to carry out R&D and foster innovation in agriculture. Sometimes, it is more efficient to organize research via participatory projects or through research contracts.Public-private partnerships, Agricultural innovations, Capacity strengthening, Agricultural research,

    Capturing the complexity of COVID-19 research: Trend analysis in the first two years of the pandemic using a bayesian probabilistic model and machine learning tools

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    Regarding Susana Mendes, this work was funded by national funds through FCT - Fundação para a Ciência e a Tecnologia, I.P., under the project MARE (UIDB/04292/2020 and UIDP/04292/2020) and the project LA/P/0069/2020 granted to the Associate Laboratory ARNET.Publications about COVID-19 have occurred practically since the first outbreak. Therefore, studying the evolution of the scientific publications on COVID-19 can provide us with information on current research trends and can help researchers and policymakers to form a structured view of the existing evidence base of COVID-19 and provide new research directions. This growth rate was so impressive that the need for updated information and research tools become essential to mitigate the spread of the virus. Therefore, traditional bibliographic research procedures, such as systematic reviews and meta-analyses, become time-consuming and limited in focus. This study aims to study the scientific literature on COVID-19 that has been published since its inception and to map the evolution of research in the time range between February 2020 and January 2022. The search was carried out in PubMed extracting topics using text mining and latent Dirichlet allocation modeling and a trend analysis was performed to analyze the temporal variations in research for each topic. We also study the distribution of these topics between countries and journals. 126,334 peerreviewed articles and 16 research topics were identified. The countries with the highest number of scientific publications were the United States of America, China, Italy, United Kingdom, and India, respectively. Regarding the distribution of the number of publications by journal, we found that of the 7040 sources Int. J. Environ. Res. Public Health, PLoS ONE, and Sci. Rep., were the ones that led the publications on COVID-19. We discovered a growing tendency for eight topics (Prevention, Telemedicine, Vaccine immunity, Machine learning, Academic parameters, Risk factors and morbidity and mortality, Information synthesis methods, and Mental health), a falling trend for five of them (Epidemiology, COVID-19 pathology complications, Diagnostic test, Etiopathogenesis, and Political and health factors), and the rest varied throughout time with no discernible patterns (Therapeutics, Pharmacological and therapeutic target, and Repercussion health services).info:eu-repo/semantics/publishedVersio

    Metabolism of triacylglycerols in Rhodococcus species: insights from physiology and molecular genetics

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    Rhodococcus bacteria possess the ability to accumulate variable amounts of triacylglycerols (TAG) during growth on diverse carbon sources. The evolution seems to have selected these microorganisms as specialists in the accumulation of TAG among bacteria, since their biochemistry is efficiently designed for the biosynthesis and mobilization of these lipids. Detailed research of rhodococcal TAG metabolism started only a few years ago; thus, the fundamental understanding of this process and its regulation remains to be clarified. However, some interesting advances in the basic knowledge on TAG metabolism in rhodococci have been made. Most studies have focused on the physiology of TAG biosynthesis and mobilization in rhodococci. Only recently, some advances in molecular biology and genetics on TAG metabolism occurred as a result of the increasing available genomic information and the development of new genetic tools for rhodococci. These studies have been focused principally on some enzymes of TAG biosynthesis, such as the wax esters/diacylglycerolacyltransferases (WS/DGAT) and TAG granule-associated proteins. In this context, the most relevant achievements of basic research in the field have been summarized in this review article
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