To investigate interactive MR-assisted bile duct drainage in pigs with the passive visualization technique using near real-time imaging.
8 bile duct drainages were placed in an open low-field MR ...system (0.2 Tesla) in 4 pigs with surgically induced cholestasis. After planning the intervention with magnetic resonance cholangiography (MRC), both the puncture and catheter placement were interactively guided using a fast T2-weighted true FISP sequence.
MRC enabled interventional planning in all puncture attempts. Punctures were unproblematic in all attempts, the bile ducts were punctured 6 times after the first and twice after the second attempt. Placement of the passively visible catheter was successful in all animals. The applied sequence enables interactive fluoroscopy-like positioning of the devices.
The procedure introduced here enables reliable and fast placement of a bile duct drainage in an animal model using a low-field MR system.
A number of different influenza C virus strains were tested for their fusion properties using a resonance energy assay which allows direct monitoring of fusion between virus membranes and artificial ...lipid vesicles. The fusion pH of various strains was found to range between 5.6 and 6.1. Haemolytic activity of the different strains with chicken erythrocytes was observed at slightly lower pH values and varied between 5.1 and 5.7. Studies of the kinetics of influenza C virus fusion showed distinct characteristics in fusion activity. A lag before onset of fusion was found with influenza C virus which was not observed for influenza A or B viruses. In addition, studies on the rate of conformational change of the influenza C virus glycoprotein, as determined by morphological changes and endogenous tryptophan fluorescence, suggest that the conformational change is rate-limiting in the fusion process, whereas for influenza A viruses the glycoprotein conformational change is fast and a later step in the fusion process is rate-limiting. Monitoring the conformational change of influenza C virus glycoprotein by the onset of trypsin susceptibility showed, however, that membrane fusion occurred in some cases without onset of trypsin susceptibility, indicating that the trypsin-susceptible conformation is a post-fusogenic conformation.
À l’échelle du globe, le secteur viticole est en pleine mutation. La mondialisation des marchés, l’augmentation de la production et l’évolution de la demande vers des vins de qualité conduisent les ...vignobles qui s’étaient spécialisés en vin de table à modifier en profondeur leurs systèmes techniques et leurs formes d’organisation. Cet article analyse comment les coopératives du Cap-Occidental, en Afrique du Sud, et du Languedoc, en France, qui dominent la production viticole dans les deux régions, s’adaptent à ces évolutions. Les coopératives sont vues comme des organisations cherchant à coordonner leurs environnements à la fois internes et externes pour anticiper et gérer les évolutions en cours à travers des innovations pouvant concerner plusieurs domaines. La comparaison des stratégies développées par les coopératives du Cap-Occidental et du Languedoc montre de quelle façon la « solidarité » émerge comme un facteur clé dans la transition vers des productions agricoles de qualité. Le statut coopératif peut néanmoins limiter la capacité d’adaptation des entreprises, ce qui amène à proposer un projet d’organisation renouvelé, basé sur un principe d’équité.
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