120 research outputs found

    Stimuli-responsive poly(ampholyte)s containing L-histidine residues: synthesis and protonation thermodynamics of methacrylic polymers in the free and in the cross-linked gel forms

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    Methacrylate-structured poly(ampholyte)s were synthesized in the homopolymer and copolymer forms starting from the N-methacryloyl-L-histidine (MHist) and the N-isopropylacrylamide (NIPAAm). They were also obtained in the cross-linked (hydrogel) form, showing a close thermodynamic behaviour as that shown by the corresponding soluble free polymer analogues. Viscometric data revealed that the minimum hydrodynamic volume of the polymer at its isoelectric point (pH 5) shifted to lower pHs as the NIPAAm content increased, and beyond a critical low MHist content the reduced viscosity decreased, even at low pHs. The phenomenon was attributed to hydrophobic forces between the isopropyl groups outweighing the repulsive electrostatic interactions of the polymer in the positively charged form. A similar behaviour was shown by the corresponding hydrogel. The latter also revealed a different phase transition phenomenon induced by external stimuli (temperature, pH, ionic strength, electric current) when compared to the acrylate-structured analogues. The polyMHist, as well as the corresponding monomer, was found for two days to be non toxic against the mouse osteoblasts (MC3T3-E1)

    Acute chest syndrome in children with sickle cell disease: Data from a national AIEOP cohort identify priority areas of intervention in a hub-and-spoke system

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    : Acute chest syndrome (ACS) is a frequent cause of hospitalization in sickle cell disease (SCD). Despite advances in acute care, many settings still lack knowledge about ACS best practices. After the AIEOP Guidelines were published in 2012, suggesting standardized management in Italy, a retrospective study was performed to assess the diagnostic and therapeutic pathways of ACS in children. From 2013 to 2018, 208 ACS episodes were presented by 122/583 kids in 11 centres. 73 were male, mean age 10.9 years, 85% African, 92% HbSS or Sβ°. In our hub-and-spoke system, a good adherence to Guidelines was documented, but discrepancies between reference centres and general hospitals were noted. Improvement is needed for timely transfer to reference centres, use of incentive spirometry, oxygen therapy and pain management

    Organizing national responses for rare blood disorders: the Italian experience with sickle cell disease in childhood

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    Background Sickle cell disease (SCD) is the most frequent hemoglobinopathy worldwide but remains a rare blood disorder in most western countries. Recommendations for standard of care have been produced in the United States, the United Kingdom and France, where this disease is relatively frequent because of earlier immigration from Africa. These recommendations have changed the clinical course of SCD but can be difficult to apply in other contexts. The Italian Association of Pediatric Hematology Oncology (AIEOP) decided to develop a common national response to the rising number of SCD patients in Italy with the following objectives: 1) to create a national working group focused on pediatric SCD, and 2) to develop tailored guidelines for the management of SCD that could be accessed and practiced by those involved in the care of children with SCD in Italy. Methods Guidelines, adapted to the Italian social context and health system, were developed by 22 pediatric hematologists representing 54 AIEOP centers across Italy. The group met five times for a total of 128 hours in 22 months; documents and opinions were circulated via web. Results Recommendations regarding the prevention and treatment of the most relevant complications of SCD in childhood adapted to the Italian context and health system were produced. For each topic, a pathway of diagnosis and care is detailed, and a selection of health management issues crucial to Italy or different from other countries is described (i.e., use of alternatives for infection prophylaxis because of the lack of oral penicillin in Italy). Conclusions Creating a network of physicians involved in the day-to-day care of children with SCD is feasible in a country where it remains rare. Providing hematologists, primary and secondary care physicians, and caregivers across the country with web-based guidelines for the management of SCD tailored to the Italian context is the first step in building a sustainable response to a rare but emerging childhood blood disorder and in implementing the World Health Organization\u2019s suggestion \u201cto design (and) implement \u2026 comprehensive national integrated programs for the prevention and management of SCD"

    Self‐Assembled Surfactant‐Polyoxovanadate Soft Materials as Tuneable Vanadium Oxide Cathode Precursors for Lithium‐Ion Batteries

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    The mixing of [V10O28]6− decavanadate anions with a dicationic gemini surfactant (gem) leads to the spontaneous self-assembly of surfactant-templated nanostructured arrays of decavanadate clusters. Calcination of the material under air yields highly crystalline, sponge-like V2O5 (gem-V2O5). In contrast, calcination of the amorphous tetrabutylammonium decavanadate allows isolation of a more agglomerated V2O5 consisting of very small crystallites (TBA-V2O5). Electrochemical analysis of the materials’ performance as lithium-ion intercalation electrodes highlights the role of morphology in cathode performance. The large crystallites and long-range microstructure of the gem-V2O5 cathode deliver higher initial capacity and superior capacity retention than TBA-V2O5. The smaller crystallite size and higher surface area of TBA-V2O5 allow faster lithium insertion and superior rate performance to gem-V2O5

    Nuovi contributi sull'insediamento dei Mattei nel rione S. Angelo e sulla costruzione del palazzo Mattei Paganica

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    Il saggio costituisce una sintesi della tesi di laurea dell’autrice. Basato sull’analisi di una documentazione archivistica in gran parte inedita e sul rilievo delle strutture edilizie, il saggio ricostruisce il processo di formazione dell’isolato Mattei a Roma, tra XV e XVI secolo, con particolare riguardo al palazzo Mattei di Paganica

    Nuovi contributi sull'insediamento dei Mattei nel rione S. Angelo e sulla costruzione del palazzo Mattei Paganica

    No full text
    Il saggio costituisce una sintesi della tesi di laurea dell’autrice. Basato sull’analisi di una documentazione archivistica in gran parte inedita e sul rilievo delle strutture edilizie, il saggio ricostruisce il processo di formazione dell’isolato Mattei a Roma, tra XV e XVI secolo, con particolare riguardo al palazzo Mattei di Paganica
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