80 research outputs found

    El teatre català es queda sense la veu crítica de Jordi Mesalles

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    EL COLCHÓN DE LANA

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    Elena Hevia (1997). EL COLCHÓN DE LANA. Nosferatu. Revista de cine. (23). http://hdl.handle.net/10251/41005.Importación Masiva2

    Landscape and agri-environmental scheme effects on ant communities in cereal croplands of central Spain

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    Agri-environmental schemes (AES) of the Common Agricultural Policy (CAP) aims at reversing the negative effects of agricultural intensification on biodiversity and ecosystem services. Landscape context may modulate, and even constraint, AES effectiveness. We evaluate AES effectiveness on ant abundance, diversity and community composition. Ants are an ecologically dominant group whose response to conservation efforts in farmland has been rarely evaluated, despite its role in weed control, particularly in Mediterranean farmland. Ants were sampled in the edge and in the centre of paired cereal fields, managed with and without AES in three study areas along a landscape complexity gradient. AES application had no significant effects on ant species richness or ant community composition. Richness increased in fields and landscapes with higher amounts of complex edges and decreased towards the centre of the fields. Specialist granivorous ants (harvester ants, Messor spp.) were the most abundant. Abundance of foraging ants increased with the amount of complex edges around fields and in the landscape. AES application increased ant abundance close to field edges but not in field centers. AES fields had less specialist granivorous foraging in their centers than in control field centers. Ant communities in Mediterranean cereal cropland were mostly constrained by the availability of complex edges, needed for nest building. AES increased the abundance of foraging ants, mostly specialist harvester ants, and its potential service of weed control, but close to field edges mainly. Measures promoting the abundance of stable edges rather than of ephemeral headlands in the landscape are essential to enhance the potential of AES for increasing ant-mediated ecosystem services of weed controlThis paper is a contribution to the EU Project QLK5-CT-2002–1495 ‘Evaluating current European Agri-environment Schemes to quantify and improve Nature Conservation efforts in agricultural landscapes (EASY)

    Estudio histórico y epistemológico de la óptica como base para la enseñanza en 2º de Bachillerato

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    [ES] En este trabajo analizamos los textos originales de los grandes científicos sobre la naturaleza de la luz destacando los avances principales que aportaron, y proponemos una relación entre dichas ideas clave y los estándares de aprendizaje que han de ser adquiridas por nuestros alumnos. A partir de estas ideas clave y teniendo en cuenta los posibles obstáculos asociados, desarrollaremos el estudio de la óptica de manera constructiva, para que tanto los alumnos, como el profesor, aprovechen en mayor medida el proceso de enseñanza-aprendizaje.Álvarez Jubete, E.; Hevia Artime, I.; Toffolatti Ballarin, L. (2020). Estudio histórico y epistemológico de la óptica como base para la enseñanza en 2º de Bachillerato. Editorial Universitat Politècnica de València. 451-459. https://doi.org/10.4995/INN2019.2019.10026OCS45145

    Targeting Nanomaterials to Head and Neck Cancer Cells Using a Fragment of the Shiga Toxin as a Potent Natural Ligand

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    Head and Neck Cancer (HNC) is the seventh most common cancer worldwide with a 5-year survival from diagnosis of 50%. Currently, HNC is diagnosed by a physical examination followed by an histological biopsy, with surgery being the primary treatment. Here, we propose the use of targeted nanotechnology in support of existing diagnostic and therapeutic tools to prevent recurrences of tumors with poorly defined or surgically inaccessible margins. We have designed an innocuous ligand-protein, based on the receptor-binding domain of the Shiga toxin (ShTxB), that specifically drives nanoparticles to HNC cells bearing the globotriaosylceramide receptor on their surfaces. Microscopy images show how, upon binding to the receptor, the ShTxB-coated nanoparticles cause the clustering of the globotriaosylceramide receptors, the protrusion of filopodia, and rippling of the membrane, ultimately allowing the penetration of the ShTxB nanoparticles directly into the cell cytoplasm, thus triggering a biomimetic cellular response indistinguishable from that triggered by the full-length Shiga toxin. This functionalization strategy is a clear example of how some toxin fragments can be used as natural biosensors for the detection of some localized cancers and to target nanomedicines to HNC lesions.Funding: This research was funded by ISCIII Projects ref. PI19/00349, DTS19/00033, co-funded by ERDF/ESF, “Investing in your future”; and MICINN Projects ref. CTM2017-84050-R, NanoBioApp, and HIPERNANO Research Networks (MINECO-17-MAT2016-81955-REDT and RED2018-102626-T), MCIU/AEI/FEDER, EU under project PGC2018-101464-B-100, COST action Nano2Clinic CA17140, and IDIVAL for the INNVAL19/12 and INNVAL20/13 projects and PREVAL18/02, PREVAL16/02 and 16/03. M.B.L. acknowledges NORTE 2020 (2014-2020 North Portugal Regional Operational Program), and the ERDF (European Regional Development Fund) Grant NORTE-01-0145-FEDER- 000019, and 2014-2020 INTERREG Cooperation Programme Spain–Portugal (POCTEP) through the project 0624-2IQBIONEURO-6-E

    Effect of Size, Shape, and Composition on the Interaction of Different Nanomaterials with HeLa Cells

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    The application of nanomaterials in the fields of medicine and biotechnology is of enormous interest, particularly in the areas where traditional solutions have failed. Unfortunately, there is very little information on how to optimize the preparation of nanomaterials for their use in cell culture and on the effects that these can trigger on standard cellular systems. These data are pivotal in nanobiotechnology for the development of different applications and to evaluate/compare the cytotoxicity among the different nanomaterials or studies. The lack of information drives many laboratories to waste resources performing redundant comparative tests that often lead to partial answers due to differences in (i) the nature of the start-up material, (ii) the preparation, (iii) functionalization, (iv) resuspension, (v) the stability/dose of the nanomaterial, etc. These variations in addition to the different analytical systems contribute to the artefactual interpretation of the effects of nanomaterials and to inconsistent conclusions between different laboratories. Here, we present a brief review of a wide range of nanomaterials (nanotubes, various nanoparticles, graphene oxide, and liposomes) with HeLa cells as a reference cellular system. These human cells, widely used as cellular models for many studies, represent a reference system for comparative studies between different nanomaterials or conditions and, in the last term, between different laboratories.This work has been supported by the Spanish MINECO and European FEDER under Project ref. PI16/000496, the NanoBioApp Network Ref. MINECO-17-MAT2016-81955-REDT. We thank IDIVAL for INNVAL15/16, INNVAL 17/11, PREVAL 16/03, 16/02, 17/04, and the Raman4clinics BMBS COST Actions BM1401 and TD1402. We also thank Débora Muñoz for her technical assistance. We are grateful to the Nikon A1R Laser Microscopy Unit and the TEM Unit of the IDIVAL Institute

    Carbon nanotubes gathered onto silica particles lose their biomimetic properties with the cytoskeleton becoming biocompatible

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    Carbon nanotubes (CNTs) are likely to transform the therapeutic and diagnostic fields in biomedicine during the coming years. However, the fragmented vision of their side effects and toxicity in humans has proscribed their use as nanomedicines. Most studies agree that biocompatibility depends on the state of aggregation/dispersion of CNTs under physiological conditions, but conclusions are confusing so far. This study designs an experimental setup to investigate the cytotoxic effect of individualized multiwalled CNTs compared to that of identical nanotubes assembled on submicrometric structures. Our results demonstrate how CNT cytotoxicity is directly dependent on the nanotube dispersion at a given dosage. When CNTs are gathered onto silica templates, they do not interfere with cell proliferation or survival becoming highly compatible. These results support the hypothesis that CNT cytotoxicity is due to the biomimetics of these nanomaterials with the intracellular nanofilaments. These findings provide major clues for the development of innocuous CNT-containing nanodevices and nanomedicines.Acknowledgments: This work was supported by the Spanish MINECO Project (references PI13/01074, PI16/00496 and CTM2014–58481-R, IDIVAL INNVAL15/15), Xunta de Galicia (Centro Singular de Investigación de Galicia-Accreditation 2016–2019 and EM2014/035), European Regional Development Fund – ERDF and Fundación Tatiana Pérez de Guzmán El Bueno

    Methylthioadenosine phosphorylase gene expression is impaired in human liver cirrhosis and hepatocarcinoma

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    Methylthioadenosine phosphorylase (MTAP) is a key enzyme in the methionine and adenine salvage pathways. In mammals, the liver plays a central role in methionine metabolism, and this essential function is lost in the progression from liver cirrhosis to hepatocarcinoma. Deficient MTAP gene expression has been recognized in many transformed cell lines and tissues. In the present work, we have studied the expression of MTAP in human and experimental liver cirrhosis and hepatocarcinoma. We observe that MTAP gene expression is significantly reduced in human hepatocarcinoma tissues and cell lines. Interestingly, MTAP gene expression was also impaired in the liver of CCl4-cirrhotic rats and cirrhotic patients. We provide evidence indicating that epigenetic mechanisms, involving DNA methylation and histone deacetylation, may play a role in the silencing of MTAP gene expression in hepatocarcinoma. Given the recently proposed tumor suppressor activity of MTAP, our observations can be relevant to the elucidation of the molecular mechanisms of multistep hepatocarcinogenesis

    Methylthioadenosine reverses brain autoimmune disease

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    OBJECTIVE: To assess the immunomodulatory activity of methylthioadenosine (MTA) in rodent experimental autoimmune encephalomyelitis (EAE) and in patients with multiple sclerosis. METHODS: We studied the effect of intraperitoneal MTA in the acute and chronic EAE model by quantifying clinical and histological scores and by performing immunohistochemistry stains of the brain. We studied the immunomodulatory effect of MTA in lymphocytes from EAE animals and in peripheral blood mononuclear cells from healthy control subjects and multiple sclerosis patients by assessing cell proliferation and cytokine gene expression, by real-time polymerase chain reaction, and by nuclear factor-kappaB modulation by Western blot. RESULTS: We found that MTA prevents acute EAE and, more importantly, reverses chronic-relapsing EAE. MTA treatment markedly inhibited brain inflammation and reduced brain damage. Administration of MTA suppressed T-cell activation in vivo and in vitro, likely through a blockade in T-cell signaling resulting in the prevention of inhibitor of kappa B (IkappaB-alpha) degradation and in the impaired activation transcription factor nuclear factor-kappaB. Indeed, MTA suppressed the production of proinflammatory genes and cytokines (interferon-gamma, tumor necrosis factor-alpha, and inducible nitric oxide synthase) and increased the production of antiinflammatory cytokines (interleukin-10). INTERPRETATION: MTA has a remarkable immunomodulatory activity and may be beneficial for multiple sclerosis and other autoimmune diseases

    Haur depresioaren detekzioa eskola-testuinguruan

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