889 research outputs found

    Ions and water transmembrane transport in nervous and testicular cultured cells in low gravity conditions

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    Aim of the present study was to investigate on the possible alter- ations induced by on ground modeled microgravity on ion-water transport proteins at cellular level. For the purpose we used astrocytes, C6 line, neurons (NT2 line from human teratocarci- noma) and testicular cells (germ cells, Sertoli cells, and Leydig cells; primary cultures from trypsinised prepuberal pig testes). Modeled microgravity was achieved by a desktop 3D Random Positioning Machine, cultures were kept rotating for 30’, 1h and 24h. After 30’, immunopositivity for the antibodies to Na+/K+ATPase and Na+/K+/Cl- co-transporters was greatly diminished, the plasma membrane appeared to be altered, and the mitochondria inner cristae were disrupted. Immunostaining to the antibody to the water channel aquaporin 4 was very bright. After 1h at random rotation immunostaining for the heat shock protein Hsp27 was visible, After 24h, immunostaining for the ion transport proteins was again like that of the controls,plasma membrane and the mitochondria were again normal. Immunostaining for aquaporin 4 become again similar to that of the controls. We conclude that low gravity induces only tran- sient alterations in the cell’s transmembrane ion-water trans- port: the cells are able to adapt to the gravity vector changes in few hours

    Molecular transport and flow past hard and soft surfaces: Computer simulation of model systems

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    The properties of polymer liquids on hard and soft substrates are investigated by molecular dynamics simulation of a coarse-grained bead-spring model and dynamic single-chain-in-mean-field (SCMF) simulations of a soft, coarse-grained polymer model. Hard, corrugated substrates are modelled by an FCC Lennard-Jones solid while polymer brushes are investigated as a prototypical example of a soft, deformable surface. From the molecular simulation we extract the coarse-grained parameters that characterise the equilibrium and flow properties of the liquid in contact with the substrate: the surface and interface tensions, and the parameters of the hydrodynamic boundary condition. The so-determined parameters enter a continuum description like the Stokes equation or the lubrication approximation.Comment: 41 pages, 13 figure

    Project MOSI: rationale and pilot-study results of an initiative to help protect zoo animals from mosquito-transmitted pathogens and contribute data on mosquito spatio–temporal distribution change

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    Mosquito-borne pathogens pose major threats to both wildlife and human health and, largely as a result of unintentional human-aided dispersal of their vector species, their cumulative threat is on the rise. Anthropogenic climate change is expected to be an increasingly significant driver of mosquito dispersal and associated disease spread. The potential health implications of changes in the spatio-temporal distribution of mosquitoes highlight the importance of ongoing surveillance and, where necessary, vector control and other health-management measures. The World Association of Zoos and Aquariums initiative, Project MOSI, was established to help protect vulnerable wildlife species in zoological facilities from mosquito-transmitted pathogens by establishing a zoo-based network of fixed mosquito monitoring sites to assist wildlife health management and contribute data on mosquito spatio-temporal distribution changes. A pilot study for Project MOSI is described here, including project rationale and results that confirm the feasibility of conducting basic standardized year-round mosquito trapping and monitoring in a zoo environment

    Factors influencing interactions in zoos: animal-keeper relationship, animal-public interactions and solitary animal groups

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    Interactions that animals experience can have a significant influence on their health and welfare. These interactions can occur between animals themselves, but also between animals and keepers, and animals and the public. Human and non-human animals come into contact with each other in a variety of settings, and wherever there is contact there is the opportunity for interaction to take place. Interaction with companion animals are well known, but human\u2013animal interaction (HAR) also occurs in the context of farms, laboratories, zoos and even the wild. This project proposes a permanent monitoring scheme to record animal-human interactions and animal-animal interactions in zoos. This will be accompanied by a survey of animal personality for welfare, husbandry, breeding programs and reintroduction purposes. The pilot project is currently based on direct monitoring of animal behaviour, use of time lapse cameras and animal personality questionnaires filled by experienced keepers. We present preliminary data regarding polar bear (Fasano Zoosafari, Italy), Sumatran tigers, Amur tigers and Asiatic lion (ZSL London and Whipsnade zoo) interactions with humans and conspecifics. These data are collected across a broad range of environmental conditions and outlines the monitoring protocols developed to collect this data.The first year data show the great adaptability of these species to ex-situ environments, low or absent negative impact of visitors\u2019 presence and the relevance of individual personality in these interactions

    The prognostic role of micro-RNAs in head and neck cancers: An umbrella review

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    We conducted an umbrella review which synthetizes the findings of systematic reviews available in the literature that investigate the prognostic role of miRNAs as potential biomarkers in the field of tertiary prevention of head and neck Cancer (HNC). We selected systematic reviews in English related to HNC, with meta-analysis of observational studies that reported quantitative prognostic measures, hazard ratios (HRs), overall survival (OS) or disease-free survival (DFS). The methodological quality of the included reviews was assessed by using the AMSTAR-2 tool. The most reported miRNAs were the following: miRNA2, Let7 family and miR17, etc. Four out of six reviews particularly emphasized the link between miRNA21 expression and HNC patients. Re-cently the cumulative effects of sets of miRNAs have been increasingly studied and might be a stronger predictor of survival than single miRNA
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