525 research outputs found

    Nicotinic Acid Adenine Dinucleotide Phosphate-induced Ca2+ Release INTERACTIONS AMONG DISTINCT Ca2+ MOBILIZING MECHANISMS IN STARFISH OOCYTES

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    An intracellular mechanism activated by nicotinic acid adenine dinucleotide phosphate (NAADP(+)) contributes to intracellular Ca(2+) release alongside inositol 1,4,5-trisphosphate (Ins-P(3)) and ryanodine receptors. The NAADP(+)-sensitive mechanism has been shown to be operative in sea urchin eggs, ascidian eggs, and pancreatic acinar cells. Furthermore, most mammalian cell types can synthesize NAADP(+), with nicotinic acid and NADP(+) as precursors. In this contribution, NAADP(+)-induced Ca(2+) release has been investigated in starfish oocytes. Uncaging of injected NAADP(+) induced Ca(2+) mobilization in both immature oocytes and in oocytes matured by the hormone 1-methyladenine (1-MA). The role of extracellular Ca(2+) in NAADP(+)-induced Ca(2+) mobilization, which was minor in immature oocytes, was instead essential in mature oocytes. Thus, the NAADP(+)-sensitive Ca(2+) pool, which is known to be distinct from those sensitive to inositol 1,4,5-trisphosphate or cyclic ADPribose, apparently migrated closer to (or became part of) the plasma membrane during the maturation process. Inhibition of both Ins-P(3) and ryanodine receptors, but not of either alone, substantially inhibited NAADP(+)-induced Ca(2+) mobilization in both immature and mature oocytes. The data also suggest that NAADP(+)-induced Ca(2+) mobilization acted as a trigger for Ca(2+) release via Ins-P(3) and ryanodine receptors

    A complexity approach for identifying aesthetic composite landscapes

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    Third European Conference, EvoMUSART 2014, Granada, Spain, April 23-25, 2014, Revised Selected Papers[Abstract] The present paper describes a series of features related to complexity which may allow to estimate the complexity of an image as a whole, of all the elements integrating it and of those which are its focus of attention. Using a neural network to create a classifier based on those features an accuracy over 85% in an aesthetic composition binary classification task is achieved. The obtained network seems to be useful for the purpose of assessing the Aesthetic Composition of landscapes. It could be used as part of a media device for facilitating the creation of images or videos with a more professional aesthetic composition.Galicia. Consellería de Innovación, Industria e Comercio; PGIDIT 10TIC105008PRPortugal. Fundação para a Ciência e a Tecnologia; PTDC/EIA-EIA/115667/200

    Ciclo de seminarios : el modelo sindical en debate

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    La publicación es el resultado del ciclo de seminarios El modelo sindical en debate, organizado por la Asociación Argentina de Especialistas en Estudios del Trabajo (ASET) y la Fundación Friedrich Ebert durante los meses de abril y mayo de 2011. El objetivo del ciclo fue contribuir a una reflexión acerca de las dimensiones sociales, culturales, históricas y legales del modelo sindical en Argentina, a la luz de los principales debates planteados en la actualidad. La publicación contiene los documentos presentados en los cuatro paneles del ciclo con la síntesis del correspondiente debate que tuvo lugar al cierre de cada panel, donde participaron reconocidos especialistas en las temáticas planteadas y actores sindicales que dieron cuenta de sus experiencias. Busca reflejar la pluralidad de posiciones existentes y algunas conclusiones que se desarrollaron en torno a las problemáticas planteadasPANEL 1: SOBRE LA VIGENCIA DEL MODELO SINDICAL ARGENTINO ¿CONTINUIDAD, REFORMA O CAMBIO? Sebastián Etchemendy ..4 PANEL 2: LA REPRESENTACIÓN SINDICAL EN LA EMPRESA. ¿UN CONCEPTO DESACTUALIZADO? Agustín Santella .. 13 PANEL 3: EL SISTEMA DE OBRAS SOCIALES Y LA COMPLEMENTARIEDAD CON EL SISTEMA PÚBLICO. ¿MODELO VIGENTE O NECESIDAD DE CAMBIO? Claudia Danani .. 34 PANEL 4: ¿EL SINDICALISMO ARGENTINO ESTÁ PREPARADO PARA UN MUNDO GLOBAL? Héctor Palomino .. 5

    De novo assembly of a transcriptome from the eggs and early embryos of Astropecten aranciacus

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    Starfish have been instrumental in many fields of biological and ecological research. Oocytes of Astropecten aranciacus, a common species native to the Mediterranean Sea and the East Atlantic, have long been used as an experimental model to study meiotic maturation, fertilization, intracellular Ca2+ signaling, and cell cycle controls. However, investigation of the underlying molecular mechanisms has often been hampered by the overall lack of DNA or protein sequences for the species. In this study, we have assembled a transcriptome for this species from the oocytes, eggs, zygotes, and early embryos, which are known to have the highest RNA sequence complexity. Annotation of the transcriptome identified over 32,000 transcripts including the ones that encode 13 distinct cyclins and as many cyclin-dependent kinases (CDK), as well as the expected components of intracellular Ca2+ signaling toolkit. Although the mRNAs of cyclin and CDK families did not undergo significant abundance changes through the stages from oocyte to early embryo, as judged by real-time PCR, the transcript encoding Mos, a negative regulator of mitotic cell cycle, was drastically reduced during the period of rapid cleavages. Molecular phylogenetic analysis using the homologous amino acid sequences of cytochrome oxidase subunit I from A. aranciacus and 30 other starfish species indicated that Paxillosida, to which A. aranciacus belongs, is not likely to be the most basal order in Asteroidea. Taken together, the first transcriptome we assembled in this species is expected to enable us to perform comparative studies and to design gene-specific molecular tools with which to tackle long-standing biological questions
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