146 research outputs found

    Laser Fabrication of Polymer Ferroelectric Nanostructures for Nonvolatile Organic Memory Devices

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    8 pags.; 5 figs.© 2015 American Chemical Society. Polymer ferroelectric laser-induced periodic surface structures (LIPSS) have been prepared on ferroelectric thin films of a poly(vinylidene fluoride-trifluoroethylene) copolymer. Although this copolymer does not absorb light at the laser wavelength, LIPSS on the copolymer can be obtained by forming a bilayer with other light-absorbing polymers. The ferroelectric nature of the structured bilayer was proven by piezoresponse force microscopy measurements. Ferroelectric hysteresis was found on both the bilayer and the laser-structured bilayer. We show that it is possible to write ferroelectric information at the nanoscale. The laser-structured ferroelectric bilayer showed an increase in the information storage density of an order of magnitude, in comparison to the original bilayer.The authors gratefully acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness (MINECO), through Contract Nos. MAT 2011-23455, MAT 2012- 33517, and CTQ 2013-43086-P. D.E.M. thanks CSIC for the tenure of JAE-Pre fellowship and Fondo Social Europeo (FSE) for cofinancing the JAE Program. A.R.R. and E.R. thank MINECO for the tenure of a FPI contract (BES-2013-062620) and a Ramón y Cajal contract (No. RYC-2011-08069), respectively.Peer Reviewe

    Magnetic study on biodistribution and biodegradation of oral magnetic nanostructures in the rat gastrointestinal tract

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    We have undertaken a magnetic study on the oral biodistribution and biodegradation of nude maghemite nanoparticles of 10 nm average size (MNP) and probiotic bacteria, Lactobacillus fermentum, containing thousands of these same nanoparticles (MNP-bacteria). Using AC magnetic susceptibility measurements of the stomach, small intestine, cecum and large intestine obtained after rat sacrifice, and iron content determination by ICP-OES, we have monitored the biodistribution and biodegradation of the maghemite nanoparticles along the gastrointestinal tract, after oral administration of both MNP and MNP-bacteria. The results revealed that the amount of magnetic nanoparticles accumulated in intestines is sensibly higher when MNP-bacteria were administered, in comparison with MNP. This confirms our initial hypothesis that the use of probiotic bacteria is a suitable strategy to assist the magnetic nanoparticles to overcome the stomach medium, and to achieve their accumulation in intestines. This finding opens doors to different applications. Since iron absorption in humans takes place precisely in the intestines, the use of MNP-bacteria as an iron supplement is a definite possibility. We have actually illustrated how the administration of MNP-bacteria to iron-deficient rats corrects the iron levels after two weeks of treatment

    Unraveling the extracellular matrix-tumor cell interactions to aid better targeted therapies for neuroblastoma

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    Treatment in children with high-risk neuroblastoma remains largely unsuccessful due to the development of metastases and drug resistance. The biological complexity of these tumors and their microenvironment represent one of the many challenges to face. Matrix glycoproteins such as vitronectin act as bridge elements between extracellular matrix and tumor cells and can promote tumor cell spreading. In this study, we established through a clinical cohort and preclinical models that the interaction of vitronectin and its ligands, such as αv integrins, are related to the stiffness of the extracellular matrix in high-risk neuroblastoma. These marked alterations found in the matrix led us to specifically target tumor cells within these altered matrices by employing nanomedicine and combination therapy. Loading the conventional cytotoxic drug etoposide into nanoparticles significantly increased its efficacy in neuroblastoma cells. We noted high synergy between etoposide and cilengitide, a high-affinity cyclic pentapeptide αv integrin antagonist. The results of this study highlight the need to characterize cell-extracellular matrix interactions, to improve patient care in high-risk neuroblastoma

    Low aerobic capacity in McArdle disease: A role for mitochondrial network impairment?

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    [Background]: McArdle disease is caused by myophosphorylase deficiency and results in complete inability for muscle glycogen breakdown. A hallmark of this condition is muscle oxidation impairment (e.g., low peak oxygen uptake (VO2peak)), a phenomenon traditionally attributed to reduced glycolytic flux and Krebs cycle anaplerosis. Here we hypothesized an additional role for muscle mitochondrial network alterations associated with massive intracellular glycogen accumulation. [Methods]: We analyzed in depth mitochondrial characteristics-content, biogenesis, ultrastructure-and network integrity in skeletal-muscle from McArdle/control mice and two patients. We also determined VO2peak in patients (both sexes, N = 145) and healthy controls (N = 133). [Results]: Besides corroborating very poor VO2peak values in patients and impairment in muscle glycolytic flux, we found that, in McArdle muscle: (a) damaged fibers are likely those with a higher mitochondrial and glycogen content, which show major disruption of the three main cytoskeleton components-actin microfilaments, microtubules and intermediate filaments-thereby contributing to mitochondrial network disruption in skeletal muscle fibers; (b) there was an altered subcellular localization of mitochondrial fission/fusion proteins and of the sarcoplasmic reticulum protein calsequestrin-with subsequent alteration in mitochondrial dynamics/function; impairment in mitochondrial content/biogenesis; and (c) several OXPHOS-related complex proteins/activities were also affected. [Conclusions]: In McArdle disease, severe muscle oxidative capacity impairment could also be explained by a disruption of the mitochondrial network, at least in those fibers with a higher capacity for glycogen accumulation. Our findings might pave the way for future research addressing the potential involvement of mitochondrial network alterations in the pathophysiology of other glycogenoses.The present study was funded by grants received from the Fondo de Investigaciones Sanitarias (FIS, PI17/02052, PI18/00139, PI19/01313, and PI20/00645) and cofunded by ‘Fondos FEDER’. Gisela Nogales-Gadea and Carmen Fiuza-Luces are supported by the Miguel Servet research contracts (ISCIII CD14/00032 and CP18/00034, respectively and cofounded by Fondos FEDER′). Research by Pedro L. Valenzuela is funded by a postdoctoral contract granted by Instituto de Salud Carlos III (Sara Borrell, CD21/00138). Monica Villarreal Salazar is supported by the Mexican National Council for Science and Technology (CONACYT)

    Low aerobic capacity in McArdle disease : A role for mitochondrial network impairment?

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    McArdle disease is caused by myophosphorylase deficiency and results in complete inability for muscle glycogen breakdown. A hallmark of this condition is muscle oxidation impairment (e.g., low peak oxygen uptake (VO)), a phenomenon traditionally attributed to reduced glycolytic flux and Krebs cycle anaplerosis. Here we hypothesized an additional role for muscle mitochondrial network alterations associated with massive intracellular glycogen accumulation. We analyzed in depth mitochondrial characteristics-content, biogenesis, ultrastructure-and network integrity in skeletal-muscle from McArdle/control mice and two patients. We also determined VO in patients (both sexes, N = 145) and healthy controls (N = 133). Besides corroborating very poor VO values in patients and impairment in muscle glycolytic flux, we found that, in McArdle muscle: (a) damaged fibers are likely those with a higher mitochondrial and glycogen content, which show major disruption of the three main cytoskeleton components-actin microfilaments, microtubules and intermediate filaments-thereby contributing to mitochondrial network disruption in skeletal muscle fibers; (b) there was an altered subcellular localization of mitochondrial fission/fusion proteins and of the sarcoplasmic reticulum protein calsequestrin-with subsequent alteration in mitochondrial dynamics/function; impairment in mitochondrial content/biogenesis; and (c) several OXPHOS-related complex proteins/activities were also affected. In McArdle disease, severe muscle oxidative capacity impairment could also be explained by a disruption of the mitochondrial network, at least in those fibers with a higher capacity for glycogen accumulation. Our findings might pave the way for future research addressing the potential involvement of mitochondrial network alterations in the pathophysiology of other glycogenoses

    The potential of probiotics in the prevention and treatment of atherosclerosis

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    Atherosclerosis, the underlying cause of cardiovascular diseases such as myocardial infarction, cerebrovascular accident and peripheral vascular disease, is the leading cause of global mortality. Current therapies against atherosclerosis, which mostly target the dyslipidemia associated with the disease, have considerable residual risk for cardiovascular disease together with various side effects. In addition, the outcomes from clinical trials on many promising pharmaceutical agents against atherosclerosis (e.g., low‐dose methotrexate, inhibitors against cholesteryl ester transfer protein) have been disappointing. Nutraceuticals such as probiotic bacteria have therefore generated substantial recent interest for the prevention of atherosclerosis and potentially as add‐ons with current pharmaceutical drugs. This review will discuss our current understanding of the anti‐atherogenic actions of probiotics from pre‐clinical and clinical studies together with their potential underlying mechanisms of action

    Revista de Vertebrados de la Estación Biológica de Doñana

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    The Osteology of Barbus bocagei (Steindachner, 1866) (Pisces: Cyprinidae).El crecimiento del Cacho (Leuciscus cephalus pyraenaicus Günther, 1862) en el rio Jarama (cuenca del Tajo)Contribución al estudio de la bermejuela, Rutilus arcasi, Steindachner 1866 de la cuenca del Júcar (Osteichthyes: Cyprinidae) 1. MorfometríaDimensiones, estructura, forma y disposición en la cavidad de los nidos de Corvus monedula.Variaciones altitudinales en la composición de las comunidades nidificantes de aves de Sierra Nevada (Sur de España)Ecomorfología de una comunidadde Passeriformes en la Sierra de Cazorla, SE de EspañaLa Distribución del pez-sol (Lepolllis gibbostlS L.) en la Península IbéricaSobre la distribución de Barbus haasi (OSTARIOPHYSI: CYPRINIDAE)La Distribución de Barbus bocagei STEINDACHNER, 1865 (OSTARIOPHYSI: CYPRINIDAE) en la Península IbéricaLighy effects on circadian locomotor activity of Lacerta lepida under constant temperatureEvaluación de diferentes métodos para estimar el área de campeo de dos especies de iguánidos.Un Casal de Cartaxo-Nottenho (Saxicola rubetra) a criar em Portugal.Nidificación de Passer hispaniolensis en antiguos nidos de Dendrocopos major thanneri.Observación de un lince ibérico (Lynx pardina) en la provincia de Lugo. Norte de España.El Visón americano, Mustela vison SCHREBER, 1777 (MAMMALIA, MUSTELIDAE) en Cataluña, N.E. de la Península Ibérica.Peer reviewe

    Optimization of microwave-assisted extraction of ergosterol from Agaricus bisporus L. by-products using response surface methodology

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    This work intends to valorise by-products of the industrial processing of mushrooms to obtain ergosterol as a value-added compound. Agaricus bisporus L. is the world’s most consumed mushroom and one of the richest sources of ergosterol. Microwave-assisted extraction was used to replace conventional techniques that are time-consuming and need large amounts of solvent. Time (3-20 min), temperature (60-210 ºC) and solid-liquid ratio (1-20 g/L) were found the relevant variables to analyze the extraction process. To maximize the ergosterol extraction yield, response surface methodology was used to optimize the process. The global optimal extraction conditions were determined and comprise: 19.4±2.9 min, 132.8±12.4 ºC and 1.6±0.5 g/L, yielding 556.1±26.2 mg of ergosterol per 100 g of mushroom by-products. In the MAE optimal conditions, it was possible to obtain ergosterol in a similar value to the one obtained in other works when using the Soxhlet extraction method with a significant decrease in the time of extraction. The results show the potential of using the by-products of an agroindustry, mushrooms processing industry, as productive sources of ergosterol.The authors acknowledge FCT (Portugal) for financial support to CIMO (PEst-OE/AGUI/0690/2014), Sandrina A. Heleno (SFRH/BPD/101413/2014) and L. Barros (SFRH/BPD/107855/2015), to FCT/MEC and FEDER under Programme PT2020 for financial support to LSRE (Project UID/EQU/50020/2013), and to QREN, ON2 and FEDER (Projects NORTE-07-0124-FEDER-000014 and NORTE-07-0162-FEDER-000050). The authors also acknowledge Xunta de Galicia for financial support of the post-doctoral researcher M.A. Prieto, and to Patrícia Diz for some support in MAE experiments

    Long-Term exercise intervention in patients with McArdle disease: clinical and aerobic fitness benefits

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    Introduction: The long-term effects of exercise in patients with McArdle disease—the paradigm of ‘exercise intolerance’—are unknown. This is an important question as the severity of the disease frequently increases with time. Purpose: To study the effects of a long-term exercise intervention on clinical and fitness-related outcomes in McArdle patients. Methods: Seventeen patients (exercise group: N=10, 6 male, 38±18yrs; control: N=7, 4 male, 38±18yrs) participated in a twoyear unsupervised intervention including moderate-intensity aerobic (cycle-ergometer exercise for 1h) and resistance (high load-low repetition circuit) training on 5 and 2-3 days/week, respectively. Patients were assessed at baseline and postintervention. Besides safety, outcomes included clinical severity (e.g., exercise intolerance features) on a 0-3 scale (primary outcome), and aerobic fitness, gross muscle efficiency, and body composition (total/regional fat, muscle, and bone mass) (secondary outcomes). Results: The exercise program was safe and resulted in a reduction of one point (-1.0, 95% confidence interval -1.6—-0.5, p=0.025) in clinical severity vs. the control group, with 60% of participants in the exercise group becoming virtually asymptomatic and with no functional limitation in daily life activities. Compared with controls, the intervention induced significant and large benefits (all p<0.05) in the workload eliciting the ventilatory threshold (both in absolute (watts, +37%) and relative units (watts·kg-1 of total body mass or of lower-limb muscle mass, +44%)), peak oxygen uptake (ml·kg-1 ·min-1 , +28%) and peak workload (absolute (+27%) and relative units (+33%)). However, no significant changes were found for muscle efficiency nor for any measure of body composition. Conclusions: A two-year unsupervised intervention including aerobic and resistance exercise is safe and induces major benefits in the clinical course and aerobic fitness of patients with McArdle disease

    Revista del Consejo Superior de Investigaciones Científicas

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    Alimentación del meloncillo Herpestes ichneumon y de la gineta Genetta genetta en la Reserva Biológica de Doñana, S.O. de la Península Ibérica.Determinación de la edad en Rana perezi Seoane, 1885. Aplicación al análisis del crecimiento somático de poblaciones.Influencias ambientales en la variación del tamaño, forma y peso de los huevos de la collalba rubia (Oenanthe hispanica L.)Características de un coro de sapos corredores (Bufo calamita) en el sureste de España.Estrategias alimentarias del ciervo (Cervus elaphus L.) en Montes de ToledoDistribución de los quirópteros de la provincia de Orense (Noroeste de España).Ecología trófica del lince ibérico en Doñana durante un periodo secoDesarrollo larvario de la rana común (Rana perezi) (anura: ranidae) en charcas temporales del noroeste de la Península Ibérica.Régimen alimenticio del mirlo común (Turdus merula) en el sureste de la Península Ibérica durante el periodo otoño-invierno.Reproducción del gorrión molinero (Passer montanus) en las Islas Canarias.Relación entre la cobertura vegetal y la distribución de nidos en las colonias de pagaza piconegraPeer reviewe
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