71 research outputs found

    Novel triblock co-polymer nanofibre system as an alternative support for embryonic stem cells growth and pluripotency

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    Conventionally, embryonic stem cells (ESCs) are cultured on gelatin or over a mitotically inactivated monolayer of mouse embryonic fibroblasts (MEFsi). Considering the lack of versatile, non-animal-derived and inexpensive materials for that purpose, we aimed to find a biomaterial able to support ESC growth in a pluripotent state that avoids the need for laborious and time-consuming MEFsi culture in parallel with mouse ESC (mESC) culture. Undifferentiated mESCs were cultured in a new nanofibre material designed for ESC culture, which is based on the self-assembly of a triblock co-polymer, poly(ethyleneglycol-β-trimethylsilyl methacrylate-β-methacrylic acid), conjugated with the peptide glycine-arginine-glycine-aspartate-serine, to evaluate its potential application in ESC research. The morphology, proliferation, viability, pluripotency and differentiation potential of mESCs were assessed. Compared to conventional stem cell culture methodologies, the nanofibres promoted a higher increase in mESCs number, enhanced pluripotency and were able to support differentiation after long-term culture. This newly developed synthetic system allows the elimination of animal-derived matrices and provides an economic method of ESC culture, made of a complex network of nanofibres in a scale similar to native extracellular matrices, where the functional properties of the cells can be observed and manipulated

    El coste de la obligatoria rehabilitación energética de la vivienda colectiva: ¿un problema social?

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    Policy changes resulting from the adoption of the Law 8/2013 will mark a before and an after, regarding the usual ways to set out the refurbishment of the collective housing blocks. This article analyses the consequences of such changes in the field of the mandatory energy refurbishment of the residential buildings and its economical and social impact. The analysis is based on a comparative study of thirty two buildings refurbished in the last years, confronting the cost of their refurbishment with the hypothetical economic cost that such policy changes would have brought about. Results obtained show that the planned objectives will not be achieved unless an ambitious public aid policy is not turned on. Even if they are suggested in the Law, this aid is not reflected in the practice. Without them, the process will not be sustainable and the good initial intentions would turn into a social problem.Los cambios normativos derivados de la aprobación de la Ley 8/2013 de Rehabilitación, Regeneración y Renovación Urbana van a suponer un antes y un después en los habituales modos de plantear los procesos de reforma de los bloques de vivienda colectiva. El artículo analiza las consecuencias de dichos cambios en el ámbito de la obligada rehabilitación energética de edificios y su repercusión económica y social. El análisis se fundamenta en el estudio comparado de treinta y dos edificios rehabilitados en los últimos años, confrontándolos con el hipotético coste económico que la aplicación de dichos cambios hubiera supuesto en sus respectivos procesos de ejecución. Los resultados obtenidos evidencian que para alcanzar los objetivos previstos, resulta fundamental potenciar la oferta de ayudas públicas, sugeridas en la ley pero no reflejadas en la práctica, en aras de la sostenibilidad del proceso y para que las mejores intenciones no deriven en un problema social. Se justifica analíticamente la teoría escogiendo un ejemplo de la obra de Félix Candela, ejecutada por medio de cáscaras cilíndricas largas de cubierta, y elaborando el proceso de cálculo necesario propuesto

    Efectos de la rehabilitación energética sobre las primeras torres residenciales de Gipuzkoa (1958-1974). Notas para los arqueólogos del futuro

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    After the enactment of the Land Law (1956) and during a cycle that lasted nearly 20 years, the first residential towers were constructed in Gipuzkoa, one of the territories of the Basque Autonomous Community, in Spain. As a result of the study of a series of representative cases, there is obtained that the architects of Gipuzkoa made use of them in order to test specific solutions. These solutions were characterized by the employment of diverse materials and textures that demonstrated the constructive logic of this new architectural type, providing to the façades of a special materiality. Half a century later, as a consequence of the energy refurbishment, these building envelopes are experiencing a process of coverage that expands with rapidity. The present article proceeds to analyze them before they disappear, drawing up a record of their constructive and structural characteristics, as well as their composition style.Tras la promulgación de la Ley del Suelo (1956) y durante un ciclo que habría de durar cerca de veinte años, fueron construidas las primeras torres residenciales en el territorio de Gipuzkoa. Del estudio de una serie de casos representativos, se obtiene que los arquitectos guipuzcoanos ensayaron en ellas una serie de soluciones específicas, caracterizadas por el empleo de diversos materiales y texturas que evidenciaban su lógica constructiva y dotaban a las fachadas de una especial materialidad. Medio siglo más tarde, como consecuencia de la rehabilitación energética, estas envolventes están siendo objeto de un proceso de cobertura que se expande con rapidez. El presente artículo procede a analizarlas antes de que desaparezcan complemente de nuestra vista, levantando acta de sus características constructivas, estructurales y compositivas

    TGF-b2 induction regulates invasiveness of theileria-transformed leukocytes and disease susceptibility

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    Theileria parasites invade and transform bovine leukocytes causing either East Coast fever (T. parva), or tropical theileriosis (T. annulata). Susceptible animals usually die within weeks of infection, but indigenous infected cattle show markedly reduced pathology, suggesting that host genetic factors may cause disease susceptibility. Attenuated live vaccines are widely used to control tropical theileriosis and attenuation is associated with reduced invasiveness of infected macrophages in vitro. Disease pathogenesis is therefore linked to aggressive invasiveness, rather than uncontrolled proliferation of Theileria-infected leukocytes. We show that the invasive potential of Theileria-transformed leukocytes involves TGF-b signalling. Attenuated live vaccine lines express reduced TGF-b2 and their invasiveness can be rescued with exogenous TGF-b. Importantly, infected macrophages from disease susceptible Holstein-Friesian (HF) cows express more TGF-b2 and traverse Matrigel with great efficiency compared to those from disease-resistant Sahiwal cattle. Thus, TGF-b2 levels correlate with disease susceptibility. Using fluorescence and time-lapse video microscopy we show that Theileria-infected, disease-susceptible HF macrophages exhibit increased actin dynamics in their lamellipodia and podosomal adhesion structures and develop more membrane blebs. TGF-b2-associated invasiveness in HF macrophages has a transcription-independent element that relies on cytoskeleton remodelling via activation of Rho kinase (ROCK). We propose that a TGF-b autocrine loop confers an amoeboid-like motility on Theileria-infected leukocytes, which combines with MMP-dependent motility to drive invasiveness and virulence

    Uncertainty characterization & validation within ESA Fire-CCI

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    Uncertainty characterisation and validation are critical phases to generate any Essential Climate Variable (ECV), and therefore both have been included as key deliverables of the ESA CCI programme [1]. All products generated by the CCI are required to have an associated per pixel uncertainty characterisation. This paper describes both the uncertainty characterisation framework and the related uncertainty validation exercise of the Fire-CCI projectinfo:eu-repo/semantics/publishedVersio

    Uncertainty Characterisation & Validation within ESA Fire-CCI

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    Uncertainty characterisation and validation are critical phases to generate any Essential Climate Variable (ECV), and therefore both have been included as key deliverables of the ESA CCI programme [1]. All products generated by the CCI are required to have an associated per pixel uncertainty characterisation. This paper describes both the uncertainty characterisation framework and the related uncertainty validation exercise of the Fire-CCI project

    A bovine lymphosarcoma cell line infected with theileria annulata exhibits an irreversible reconfiguration of host cell gene expression

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    Theileria annulata, an intracellular parasite of bovine lymphoid cells, induces substantial phenotypic alterations to its host cell including continuous proliferation, cytoskeletal changes and resistance to apoptosis. While parasite induced modulation of host cell signal transduction pathways and NFκB activation are established, there remains considerable speculation on the complexities of the parasite directed control mechanisms that govern these radical changes to the host cell. Our objectives in this study were to provide a comprehensive analysis of the global changes to host cell gene expression with emphasis on those that result from direct intervention by the parasite. By using comparative microarray analysis of an uninfected bovine cell line and its Theileria infected counterpart, in conjunction with use of the specific parasitacidal agent, buparvaquone, we have identified a large number of host cell gene expression changes that result from parasite infection. Our results indicate that the viable parasite can irreversibly modify the transformed phenotype of a bovine cell line. Fifty percent of genes with altered expression failed to show a reversible response to parasite death, a possible contributing factor to initiation of host cell apoptosis. The genes that did show an early predicted response to loss of parasite viability highlighted a sub-group of genes that are likely to be under direct control by parasite infection. Network and pathway analysis demonstrated that this sub-group is significantly enriched for genes involved in regulation of chromatin modification and gene expression. The results provide evidence that the Theileria parasite has the regulatory capacity to generate widespread change to host cell gene expression in a complex and largely irreversible manner

    The apicomplexan plastid and its evolution

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    Protistan species belonging to the phylum Apicomplexa have a non-photosynthetic secondary plastid—the apicoplast. Although its tiny genome and even the entire nuclear genome has been sequenced for several organisms bearing the organelle, the reason for its existence remains largely obscure. Some of the functions of the apicoplast, including housekeeping ones, are significantly different from those of other plastids, possibly due to the organelle’s unique symbiotic origin
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