http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Thu, 20 Jun 2013 01:39:46 GMT 2013-06-20T01:39:46Z http://hdl.handle.net/2067/1666 Title: Dispositivi medici di collagene utilizzati come agenti emostatici e cicatrizzanti Authors: Taddei, Anna Rita; Picchietti, Simona; Gambellini, Gabriella; Fausto, Anna Maria; Giorgi, F.; Cervadoro, E.; Ricciuti, F. Abstract: Quattro dispositivi medici di collagene sono stati esaminati al microscopio elettronico per determinare le migliori condizioni strutturali che ne giustificano il ruolo come agenti emostatici e cicatrizzanti. I parametri che sono stati considerati più efficaci per il processo di guarigione sono la struttura interstiziale e lo spessore dei fasci di collagene che la delimitano. Spazi interstiziali troppo grandi o troppo piccoli non sono in grado di sostenere la migrazione cellulare, mentre fasce di collagene troppo fini o troppo spessi possono influenzare il tempo di persistenza del dispositivo sulla ferita. Sulla base di questi criteri, è stato trovato che i campioni di Condress realizzano il miglior compromesso tra l'estensione della struttura interstiziale e lo spessore dei fasci di collagene.; Four collagen samples were examined at the electron microscope to find out the best structural conditions satisfying their haemostatic and cicatrizing roles. Parameters considered most effective during healing process are the mesh substructure and the thickness of the collagen strands. Meshes too large or too small may not be suitable for sustaining cell migration, while collagen strands too thin or too thick may affect the actual persistence of the medical device on the wounded area. Based on this criteria, Condress samples are thought to provide the best structural compromise between extension of the mesh areas and thickness of the collagen strands. Description: L'articolo è disponibile sul sito dell'editore http://www.seuroma.com/ Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1666 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1474 Title: The secondary metabolite euplotin c induces apoptosis-like death in the marine ciliated protist euplotes vannus Authors: Cervia, Davide; Di Giuseppe, Graziano; Ristori, Chiara; Martini, Davide; Gambellini, Gabriella; Bagnoli, Paola; Dini, Fernando Abstract: The sesquiterpenoid euplotin C is a secondary metabolite produced by the ciliated protist Euplotes crassus and provides a mechanism for damping populations of potential competitors. Indeed, E. crassus is virtually resistant to its own product while different non-producer species representing an unbiased sample of the marine, interstitial, ciliate diversity are sensitive. For instance, euplotin C exerts a marked disruption of different homeostatic mechanisms in Euplotes vannus. We demonstrate by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay that euplotin C quickly decreases viability and mitochondrial function of E. vannus with a very high efficacy and at micromolar potency. In addition, euplotin C induces apoptosis in E. vannus as 4,6-diamino-2-phenylindole and Terminal Transferase dUTP Nick End Labeling staining show the rapid condensation and fragmentation of nuclear material in cells treated with euplotin C. These effects occur without detectable permeabilisation or rupture of cell membranes and with no major changes in the overall morphology, although some traits, such as vacuolisation and disorganised microtubules, can be observed by transmission electron microscopy. In particular, E. vannus show profound changes of the mitochondrial ultrastructure. Finally, we also show that caspase activity in E. vannus is increased by euplotin C. These data elucidate the pro-apoptotic role of euplotin C and suggest a mechanism for its impact on natural selection. Description: L'articolo è disponibile sul sito dell'editore http://onlinelibrary.wiley.com/ Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1474 2008-12-31T23:00:00Z