170 research outputs found
Biodegradable polyesters reinforced with triclosan loaded polylactide micro/nanofibers: Properties, release and biocompatibility
Mechanical properties and drug release behavior were studied for three biodegradable polyester matrices (polycaprolactone, poly(nonamethylene azelate) and the copolymer derived from 1,9-nonanediol and an equimolar mixture of azelaic and pimelic acids) reinforced with polylactide (PLA) fibers. Electrospinning was used to produce suitable mats constituted by fibers of different diameters (i.e. from micro- to nanoscale) and a homogeneous dispersion of a representative hydrophobic drug (i.e. triclosan). Fabrics were prepared by a molding process, which allowed cold crystallization of PLA micro/nanofibers and hot crystallization of the polyester matrices. The orientation of PLA molecules during electrospinning favored the crystallization process, which was slightly enhanced when the diameter decreased. Incorporation of PLA micro/nanofibers led to a significant increase in the elastic modulus and tensile strength, and in general to a decrease in the strain at break. The brittle fracture was clearer when high molecular weight samples with high plastic deformation were employed. Large differences in the release behavior were detected depending on the loading process, fiber diameter size and hydrophobicity of the polyester matrix. The release of samples with the drug only loaded into the reinforcing fibers was initially fast and then became slow and sustained, resulting in longer lasting antimicrobial activity. Biocompatibility of all samples studied was demonstrated by adhesion and proliferation assays using HEp-2 cell cultures
VPL: laboratorio virtual de programación para Moodle
En este trabajo se presenta VPL (Virtual
Programming Lab), una herramienta software de
código abierto que permite la gestión de prácticas
de programación en Moodle. Esta herramienta
está compuesta de un módulo Moodle, un applet
editor de código fuente y un demonio Linux que
permite la ejecución remota de programas de
forma segura. Pretende ahorrar tiempo y mejorar
la gestión general de este tipo de actividades,
además de permitir la realización de las prácticas
sólo con un navegador. Sus características más
destacadas son: la posibilidad de editar el código
fuente y ejecutar las prácticas de forma interactiva
desde el navegador, ejecutar pruebas que revisen
las prácticas y analizar la similitud entre prácticas
para el control del plagio. Esta herramienta se ha
empleado con éxito en diversas asignaturas
durante el año 2009. VPL está disponible para su
descarga en http://vpl.dis.ulpgc.es.Peer Reviewe
Synthesis and reactivity of new silyl-substituted monocyclopentadienyl molybdenum and tungsten complexes
The functionalized silylated cyclopentadienyl molybdenum and tungsten complexes [MCpCl(CO)3H] (M=Mo, W; CpCl=η5-C5H4SiMe2Cl) are prepared easily from the reaction of [M(CO)3(NCMe)3] with C5H5SiMe2Cl in refluxing THF, via C–H activation and H transfer to the metal centre. Metathetical replacement of hydride by chloride is readily achieved when their methylene chloride solutions are treated with a few milliliters of CCl4 to give the chloro complexes [MCpCl(CO)3Cl] (M=Mo, W). The chloro–molybdenum complexes react with 1/2 equivalent of deoxygenated water to give the corresponding dinuclear complexes [{Mo(CO)3X}2(μ-CpOCp)], (X=H, Cl; CpOCp=η5-C5H4-SiMe2-O-SiMe2-η5-C5H4), whereas their reaction with one equivalent of anhydrous LiOH in toluene leads to selective substitution of the silicon-bonded chlorine atom to give the hydroxo complexes [MoCpOH(CO)3X] (X=H, Cl; CpOH=η5-C5H4SiMe2OH). These hydroxosilyl complexes can be transformed into the dinuclear compounds [{Mo(CO)3X}2(μ-CpOCp)] by heating (50°C, 2 h) or by their reaction with one equivalent of the respective hydrido and chloro derivatives [MoCpCl(CO)3X]. Total decarbonylation of the hydrido compounds results from oxidation with a stoichiometric amount of PCl5 to give the paramagnetic molybdenum(V) and tungsten(V) complexes [MCpClCl4] (M=Mo, W). Reactions of these complexes with one equivalent of NH2R in the presence of NEt3 yield the imido derivatives [MCpCl(NR)Cl2] (M=Mo, R=2,6-Me2-Ph; M=W, R=tBu) and subsequent oxidation of the tungsten complex with 1/2 equivalent of PCl5 gives [WCpCl(NtBu)Cl3]. Reduction of [MoCpClCl4] with two equivalents of Na/Hg gives the dinuclear molybdenum(III) complex [MoCpCl]2(μ-Cl)4. All of the reported compounds were characterized by elemental analysis and 1H- and 13C NMR-spectroscopy.The authors acknowledge DGICYT (project PB92-0178-C) for financial support
Caracterización lesional y etiológica de neumonías en vacuno de cebo sacrificado en matadero
Trabajo presentado a la: XXVII Reunión de la Sociedad Española de Anatomía Patológica Veterinaria. (Barcelona, España, 17-19 junio de 2015).Peer Reviewe
Stem cells as a therapeutic tool for the blind: biology and future prospects
Retinal degeneration due to genetic, diabetic and age-related disease is the most common cause of blindness in the developed world. Blindness occurs through the loss of the light-sensing photoreceptors; to restore vision, it would be necessary to introduce alternative photosensitive components into the eye. The recent development of an electronic prosthesis placed beneath the severely diseased retina has shown that subretinal stimulation may restore some visual function in blind patients. This proves that residual retinal circuits can be reawakened after photoreceptor loss and defines a goal for stem-cell-based therapy to replace photoreceptors. Advances in reprogramming adult cells have shown how it may be possible to generate autologous stem cells for transplantation without the need for an embryo donor. The recent success in culturing a whole optic cup in vitro has shown how large numbers of photoreceptors might be generated from embryonic stem cells. Taken together, these threads of discovery provide the basis for optimism for the development of a stem-cell-based strategy for the treatment of retinal blindness
Food sources of nutrients in the diet of Spanish children: the Four Provinces Study
The aim of the present study was to assess the principal food sources of energy and nutrients among Spanish children. We used a cross-sectional study design, based on results obtained from a food-frequency questionnaire. The sample included 1112 children, aged 6-7 years, from Cadiz, Madrid, Orense and Murcia, Spain. Children were selected through random cluster-sampling in schools. We analysed the percentage contributed by each food item to total energy and nutrient intake. The most important food sources were: white bread in the case of carbohydrate (13.4 %); olive oil in the case of total lipids (18.3 %) and monounsaturated fatty acids (29.2 %); whole milk in the case of protein (10.2 %) and saturated fatty acids (14.9 %); chips (French fried potatoes) in the case of polyunsaturated fatty acids (30.4 %). The greatest proportion of Na, consumed in excess, came from salt added to meals. Ham ranked second as a source of saturated fats. Fruits and green leafy vegetables proved to have great relevance as sources of fibre and vitamins, though with regard to the latter, it was observed that fortified foods (breakfast cereals, dairy products, fruit juices, etc.) had come to play a relevant role in many cases. In conclusion, the nutritional profile of Spanish school-aged children aged 6-7 years could be improved by nutritional policies targeted at limiting their consumption of ham (cured or cooked) and of salt added to meals, replacing whole milk with semi-skimmed milk, encouraging the consumption of products rich in complex carbohydrates already present in children's diets (bread, pasta, rice) and promoting less fatty ways of cooking food.This study was partly funded by grants from the Inter-national Olive Oil Board (Consejo Oleı ́cola Internacional),Madrid Regional Authority (Comunidad de Madrid), PedroBarrie ́de la Maza Foundation and Eugenio Rodrı ́guezPascual FoundationS
Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models
© 2018 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Secondary electron emission has an important role on the triggering of the multipactor effect; therefore, its study and characterization are essential in radio-frequency waveguide applications. In this paper, we propose a theoretical model, based on equivalent circuit models, to properly understand charging and discharging processes that occur in dielectric samples under electron irradiation for secondary electron emission characterization. Experimental results obtained for Pt, Si, GaS, and Teflon samples are presented to verify the accuracy of the proposed model. Good agreement between theory and experiments has been found.The authors would like to thank the European High Power Space Materials Laboratory for its contribution-a laboratory funded by the European Regional Development Fund-a way of making Europe. Many thanks to the University of Valencia (Spain) for supporting this research activity with the internal program "Assistance for temporary stays of invited researchers within the framework of the Subprogramme Attraction of Talent 2015".Bañón, D.; Socuellamos, JM.; Mata-Sanz, R.; Mercadé-Morales, L.; Gimeno Martínez, B.; Boria Esbert, VE.; Raboso García-Baquero, D.... (2018). Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models. IEEE Transactions on Plasma Science. 46(4):859-867. https://doi.org/10.1109/TPS.2018.2809602S85986746
Genetic Structure of Modern Durum Wheat Cultivars and Mediterranean Landraces Matches with Their Agronomic Performance
A collection of 172 durum wheat landraces from 21 Mediterranean countries and 20 modern cultivars were phenotyped in 6 environments for 14 traits including phenology, biomass, yield and yield components. The genetic structure of the collection was ascertained with 44 simple sequence repeat markers that identified 448 alleles, 226 of them with a frequency lower than 5%, and 10 alleles per locus on average. In the modern cultivars all the alleles were fixed in 59% of the markers. Total genetic diversity was HT = 0.7080 and the genetic differentiation value was GST = 0.1730. STRUCTURE software allocated 90.1% of the accessions in five subpopulations, one including all modern cultivars, and the four containing landrace related to their geographic origin: eastern Mediterranean, eastern Balkans and Turkey, western Balkans and Egypt, and western Mediterranean. Mean yield of subpopulations ranged from 2.6 t ha-1 for the western Balkan and Egyptian landraces to 4.0 t ha-1 for modern cultivars, with the remaining three subpopulations showing similar values of 3.1 t ha-1. Modern cultivars had the highest number of grains m-2 and harvest index, and the shortest cycle length. The diversity was lowest in modern cultivars (HT = 0.4835) and highest in landraces from the western Balkans and Egypt (HT = 0.6979). Genetic diversity and AMOVA indicated that variability between subpopulations was much lower (17%) than variability within them (83%), though all subpopulations had similar biomass values in all growth stages. A dendrogram based on simple sequence repeat data matched with the clusters obtained by STRUCTURE, improving this classification for some accessions that have a large admixture. landraces included in the subpopulation from the eastern Balkans and Turkey were separated into two branches in the dendrogram drawn with phenotypic data, suggesting a different origin for the landraces collected in Serbia and Macedonia. The current study shows a reliable relationship between genetic and phenotypic population structures, and the connection of both with the geographic origin of the landraces.The research was funded by the Ministerio de Economía y competitividad project AGL-2006-09226-C02-01, and Dr. Jose Miguel Soriano is funded by Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (http://www.mineco.gob.es/)
Caracterización lesional y etiológica de neumonías en vacuno de cebo sacrificado en matadero
El Complejo Respiratorio Bovino constituye una importante enfermedad en bovinos de cebo. Los agentes etiológicos principalmente implicados en este síndrome incluyen virus (BoHv1,PI-3, BVDv, bRSV), bacterias (Mannheimia haemolytica, Pasteurella multocida, Histophilussomni, Trueperella pyogenes) y Mycoplasma bovis. Dentro de este síndrome, la neumonía es la lesión más relevante. Este estudio se ha realizado en animales de cebo sacrificados en matader
A Functional Pipeline of Genome-Wide Association Data Leads to Midostaurin as a Repurposed Drug for Alzheimer’s Disease
Genome-wide association studies (GWAS) constitute a powerful tool to identify the different biochemical pathways associated with disease. This knowledge can be used to prioritize drugs targeting these routes, paving the road to clinical application. Here, we describe DAGGER (Drug Repositioning by Analysis of GWAS and Gene Expression in R), a straightforward pipeline to find currently approved drugs with repurposing potential. As a proof of concept, we analyzed a meta-GWAS of 1.6 × 107 single-nucleotide polymorphisms performed on Alzheimer’s disease (AD). Our pipeline uses the Genotype-Tissue Expression (GTEx) and Drug Gene Interaction (DGI) databases for a rational prioritization of 22 druggable targets. Next, we performed a two-stage in vivo functional assay. We used a C. elegans humanized model over-expressing the Aβ1-42 peptide. We assayed the five top-scoring candidate drugs, finding midostaurin, a multitarget protein kinase inhibitor, to be a protective drug. Next, 3xTg AD transgenic mice were used for a final evaluation of midostaurin’s effect. Behavioral testing after three weeks of 20 mg/kg intraperitoneal treatment revealed a significant improvement in behavior, including locomotion, anxiety-like behavior, and new-place recognition. Altogether, we consider that our pipeline might be a useful tool for drug repurposing in complex diseases.This work was mainly financed by Programa Operativo FEDER funds from the European Union through grant UMA20-FEDERJA-133. We thank Fundacion SantÁngela for co-funding with grant 83/23.04.2021. P.G.-G. is supported by the CIBERNED employment plan CNV-304-PRF-866. CIBERNED is integrated into Instituto de Salud Carlos III. I.d.R is supported by a national grant from the Instituto de Salud Carlos III FI20/00215. A.R. is supported by national grants PI13/02434, PI16/01861, PI17/01474, PI19/01240, and PI19/01301. A.M.B.-L. and M.J.M. were funded by grant PID2020-120463RB-I00 funded by the Spanish Ministerio de Ciencia e Innovación. A.C.-Z. holds a postdoctoral research contract from Secretaría General de Universidades, Investigación y Tecnología–Junta de Andalucía (POSTDOC21_00365). B.P.S (IFI21/00024) holds an “iPFIS” predoctoral contract from the National System of Health, EU-ERDF-ISCIII. M.d.C.M.-P. holds predoctoral grants from the Spanish Ministry of Science, Innovation and Universities (FPU17/00276). P.R. (CP19/00068) holds a “Miguel Servet” research contract from the National System of Health, ISCIII co-funded by the European Social Fund, “Investing in your future,” Gobierno de España. This research was funded by Delegación del Gobierno para el Plan Nacional sobre Drogas, Ministerio de Salud, Gobierno de España (PND2020/048). Ethovision XT software v17 (Noldus, Wageningen, The Netherlands) funded by Plan Propio, Universidad de Málaga
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