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By coating the alveolar air-liquid interface, lung surfactant overwhelms surface tension forces that, otherwise, would hinder the lifetime effort of breathing. Years of research have provided a picture of how highly hydrophobic and specialized proteins in surfactant promote rapid and efficient formation of phospholipid-based complex three-dimensional films at the respiratory surface, highly stable under the demanding breathing mechanics. However, recent evidence suggests that the structure and performance of surfactant typically isolated from bronchoalveolar lung lavages may be far from that of nascent, still unused, surfactant as freshly secreted by type II pneumocytes into the alveolar airspaces. In the present work, we report the isolation of lung surfactant from human amniotic fluid (amniotic fluid surfactant, AFS) and a detailed description of its composition, structure, and surface activity in comparison to a natural surfactant (NS) purified from porcine bronchoalveolar lavages. We observe that the lipid/ protein complexes in AFS exhibit a substantially higher lipid packing and dehydration than in NS. AFS shows melting transitions at higher temperatures than NS and a conspicuous presence of nonlamellar phases. The surface activity of AFS is not only comparable with that of NS under physiologically meaningful conditions but displays significantly higher resistance to inhibition by serum or meconium, agents that inactivate surfactant in the context of severe respiratory pathologies. We propose that AFS may be the optimal model to study the molecular mechanisms sustaining pulmonary surfactant performance in health and disease, and the reference material to develop improved therapeutic surfactant preparations to treat yet unresolved respiratory pathologies., Ministerio de Ciencia, Innovación y Universidades (MCIU), Ministerio de Educación, Gobierno Regional de Madrid, Sección Deptal. de Bioquímica y Biología Molecular (Biológicas), Fac. de Ciencias Biológicas, TRUE, pub

[ES] A través del presente trabajo se ha estudiado y analizado el sector vitivinícola, viendo cómo ha evolucionado en los últimos años, tanto en el mundo, como en España. De este modo se analiza el contexto donde se desarrollan las empresas vitivinícolas y se ha procedido a analizar una muestra de cooperativas y SAT, para poder así establecer su situación de solvencia y fortaleza frente a la crisis generalizada en la que nos encontramos. Así, cobra especial importancia la posibilidad de predecir situaciones de insolvencia económica a partir de modelos estadísticos generados con información económico financiera de las propias empresas. Este tipo de modelos económicos ha sido el objetivo de múltiples investigaciones con el fin de prever el fracaso empresarial de empresas comunes, siendo prácticamente inexistente la aplicación de estos modelos a empresas cooperativas vitivinícolas. En el presente trabajo se trata de aplicar los modelos existentes a empresas cooperativas vitivinícola