14 research outputs found
Nella libertà educare alla libertà. Documenti dalla manifestazione internazionale di Bologna 17 gennaio - 3 febbraio 2000
No full textSenso del molteplice e responsabilità dell'insegnante, Sandra Chistolini - Parte prima: Istituzioni pubbliche ed iniziativa privata per l’innovazione dell’educazione nell’Europa del Duemila - Educazione alla libertà e rinnovamento culturale per l'evoluzione sociale, Fabio Fantuzzi - Una scuola per l'uomo, Salvatore Colonna - Strutture nascenti di partecipazione europea, Bruno Sandkühler - Sogno europeo, incubo italiano: il diritto internazionale e l’anomalia della nostra scuola nel contesto dell'Unione Europea, Mario Mauro - Education: freedom and financing in Europe Educazione: libertà e finanziamento in Europa, Carlos Diaz Muniz - Il diritto all’infanzia, Antonio Masci - L’eredità di Maria Montessori e la scuola di oggi, Pietro De Santis - Principali caratteristiche dell’associazione FAES, Mario Viscovi - Il rischio educativo: l’educazione come sfida della libertà, Franco Nembrini - L’autoeducazione nell’esperienza della scuola Waldorf, Sandra Chistolini - Una ipotesi di scuola informale. Dalla metantropologia alla metapedagogia, Giulio Sforza -Parte seconda: Verso un’alleanza per il diritto all’infanzia -The children of the 21st century - I bambini del 21° secolo, Joan Almon - Valutazione neuropsicologica prescolare della crescita del comportamento per un corretto inserimento scolastico, Angelo Cioci - Terra, acqua, legno, ferro e fuoco: i diritti naturali di bimbe e bimbi, Gianfranco Zavalloni - Gli spazi delle città: alleanze nuove da fare per libertà antiche da riconquistare, Dario Manuetti - Condividere i valori per un mondo migliore. Un programma in campo educativo, Antonella Ferrari -Vedere il bambino come un essere divino: il diritto del bambino all’autorealizzazione, Margareth Rathwell e Nicola Jane Tareha - L'infanzia: campo di collaborazione tra pedagogia e medicina, Angelo Fierro - L’educazione al patto, Giovanni Catti - Parte terza: Il percorso artistico-scientifico nella lezione di Rudolf Steiner - Una nuova architettura per l’educazione alla libertà, Stefano Andi - I fondamenti e la pratica della pedagogia steineriana, Thomas Homberger - Il bambino al centro del dialogo tra scuola e famiglia, Sabino Pavone - Il sogno di una pedagogia al servizio dell’uomo, Giuseppe Leonelli - L’educazione come fondamento dello sviluppo dell’individualità e premessa per una sana e ricca vita economica e sociale, Mario Conti -Gli Autor
Distribution of GD3 in DPPC monolayers: A thermodynamic and atomic force microscopy combined study
No full textGangliosides are the main component of lipid rafts. These microdomains, floating in the outer lea. et of cellular membrane, play a key role in fundamental cellular functions. Little is still known about ganglioside and phospholipid interaction. We studied mixtures of dipalmitoylphosphatidylcholine and GD3 (molar fraction of 0.2, 0.4, 0.6, 0.8) using complementary techniques: 1), thermodynamic properties of the Langmuir-Blodgett films were assessed at the air-water interface (surface tension, surface potential); and 2), three-dimensional morphology of deposited films on mica substrates were imaged by atomic force microscopy. Mixture thermodynamics were consistent with data in the literature. In particular, excess free energy was negative at each molar fraction, thus ruling out GD3 segregation. Atomic force microscopy showed that the height of liquid-condensed domains in deposited films varied with GD3 molar fraction, as compatible with a lipid aggregation model proposed by Maggio. No distinct GD3-rich domain was observed inside the films, suggesting that GD3 molecules gradually mix with dipalmitoylphosphatidylcholine molecules, confirming DeltaG data. Morphological analysis revealed that the shape of liquid-condensed domains is strongly influenced by the amount of GD3, and an interesting stripe-formation phenomenon was observed. These data were combined with the thermodynamic results and interpreted in the light of McConnell's model
P-glycoprotein inserted in planar bilayers formed from liposomes opened on amorphous carbon Langmuir-Blodgett monolayer
No full textP-glycoprotein inserted in planar lipid bilayers formed by liposomes opened on amorphous carbon and Langmuir-Blodgett monolayer
No full textAbstractThe insertion of proteins into planar lipid layers is of outstanding interest as the resulting films are suitable for the investigation of protein structure and aggregation in a lipid environment and/or the development of biotechnological applications as biosensors. In this study, purified P-glycoprotein (P-gp), a membrane drug pump, was incorporated in model membranes deposited on solid supports according to the method by Puu and Gustafson, Biochim. Biophys. Acta 1327 (1997) 149-161. The models were formed by a double lipid layer obtained by opening P-gp-containing liposomes onto two hydrophobic supports: amorphous carbon films and Langmuir–Blodgett (L–B) lipid monolayers, which were then observed by transmission electron microscopy and atomic force microscopy, respectively. Before the opening of liposomes, the P-gp structure and functionality were verified by circular dichroism spectroscopy and enzymatic assay. Our micrographs showed that liposomes containing P-gp fuse to the substrates more easily than plain liposomes, which keep their rounded shape. This suggests that the protein plays an essential role in the fusion of liposomes. To localize P-gp, the immunogold labeling of two externally exposed protein epitopes was carried out. Both imaging techniques confirmed that P-gp was successfully incorporated in the model membranes and that the two epitopes preserved the reactivity with specific mAbs, after sample preparation. Model membranes obtained on L–B monolayer incorporated few molecules with respect to those incorporated in the model membrane deposited onto amorphous carbon, probably because of the different mechanism of proteoliposome opening. Finally, all particles appeared as isolated units, suggesting that P-gp molecules were present as monomers
Analysis of Organ Donation in Italy
No full text In 1995 the Italian Institute of Health began assembling information regarding organ donors, recipients, and transplants. Data on more than 3000 transplants were collected and recorded to date. In addition to characteristics of donors and donating hospitals, this article describes donation activity and organ procurement in Italy from 1992 to 1996. Despite the encouraging results, the donation situation in Italy remains a challenge due to the nonhomogeneous distribution of organ donation throughout the country. It is hoped that an increase in the rate of organ donation and procurement in some regions will enable Italy to reach the European mean. </jats:p
A 5-Year Analysis of Organ Donors and Recipients in Italy
No full text This article describes the improvement of organ donation and transplantation in Italy during 1995–1999. In 1999, the mean number of donors per million population reached 13.7 in Italy. In addition, an analysis regarding major characteristics of donors and recipients is presented, focusing particularly on donor characteristics that have changed in the past 5 years. Despite the encouraging results, further efforts are required to reach the European mean, which still remains higher than the Italian national mean. In particular, an increase of organ donation and procurement in regions with a poor activity in this field is crucial. A 1999 law on donation and transplantation should help in solving problems that continue to affect part of the nation, especially preparing the healthcare staff dedicated to organ retrieval to promote organ procurement. </jats:p
Brain tumor stem cell dancing
No full textBackground. Issues regarding cancer stem cell (CSC) movement are important in neu-rosphere biology as cell-cell or cell-environment interactions may have significant impacts on CSC differentiation and contribute to the heterogeneity of the neurosphere. Aims. Despite the growing body of literature data on the biology of brain tumor stem cells, floating CSC-derived neurospheres have been scarcely characterized from a morphological and ultrastructural point of view. Results. Here we report a morphological and ultrastructural characterization performed by live imaging and scanning electron microscopy. Glioblastoma multiforme (GBM) CSC-derived neurospheres are heterogeneous and are constituted by cells, morphologically different, capable of forming highly dynamic structures. These dynamic structures are regulated by not serendipitous cell-cell interactions, and they synchronously pulsate following a cyclic course made of “fast” and “slow” alternate phases. Autocrine/paracrine non canonical Wnt signalling appears to be correlated with the association status of neurospheres. Conclusions. The results obtained suggest that GBM CSCs can behave both as independents cells and as “social” cells, highly interactive with other members of its species, giving rise to a sort of “multicellular organism”.
Brain tumor stem cell dancing
No full textBackground. Issues regarding cancer stem cell (CSC) movement are important in neurosphere biology as cell-cell or cell-environment interactions may have significant impacts on CSC differentiation and contribute to the heterogeneity of the neurosphere. Aims. Despite the growing body of literature data on the biology of brain tumor stem cells, floating CSC-derived neurospheres have been scarcely characterized from a morphological and ultrastructural point of view. Results. Here we report a morphological and ultrastructural characterization performed by live imaging and scanning electron microscopy. Glioblastoma multiforme (GBM) CSC-derived neurospheres are heterogeneous and are constituted by cells, morphologically different, capable of forming highly dynamic structures. These dynamic structures are regulated by not serendipitous cell-cell interactions, and they synchronously pulsate following a cyclic course made of "fast" and "slow" alternate phases. Autocrine/paracrine non canonical Wnt signalling appears to be correlated with the association status of neurospheres. Conclusions. The results obtained suggest that GBM CSCs can behave both as independents cells and as "social" cells, highly interactive with other members of its species, giving rise to a sort of "multicellular organism"
Native metastable prefibrillar oligomers are the most neurotoxic species among amyloid aggregates
No full textAbstractMany proteins belonging to the amyloid family share the tendency to misfold and aggregate following common steps, and display similar neurotoxicity. In the aggregation pathway different kinds of species are formed, including several types of oligomers and eventually mature fibers. It is now suggested that the pathogenic aggregates are not the mature fibrils, but the intermediate, soluble oligomers. Many kinds of aggregates have been described to exist in a metastable state and in equilibrium with monomers. Up to now it is not clear whether a specific structure is at the basis of the neurotoxicity. Here we characterized, starting from the early aggregation stages, the oligomer populations formed by an amyloid protein, salmon calcitonin (sCT), chosen due to its very slow aggregation rate. To prepare different oligomer populations and characterize them by means of photoinduced cross-linking SDS-PAGE, Energy Filtered-Transmission Electron Microscopy (EF-TEM) and Circular Dichroism (CD) spectroscopy, we used Size Exclusion Chromatography (SEC), a technique that does not influence the aggregation process leaving the protein in the native state. Taking advantage of sCT low aggregation rate, we characterized the neurotoxic potential of the SEC-separated, non-crosslinked fractions in cultured primary hippocampal neurons, analyzing intracellular Ca2+ influx and apoptotic trend. We provide evidence that native, globular, metastable, prefibrillar oligomers (dimers, trimers and tetramers) were the toxic species and that low concentrations of these aggregates in the population was sufficient to render the sample neurotoxic. Monomers and other kind of aggregates, such as annular or linear protofibers and mature fibers, were totally biologically inactive
