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1.
Biomacromolecules ; 24(5): 2356-2368, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37094251

RESUMEN

In the last years, the exponential growth in the demand of petroleum-based plastic materials, besides the extreme exploitation of nonrenewable resources, lead to the mismanagement of their disposal and to serious ecological issues related to their dispersion in the environment. Among the possible practical solutions, the design of biobased and biodegradable polymers represents one of the most innovative challenges. In such a context, the eco-design of an aromatic-aliphatic multiblock copolymer based on poly(lactic acid) and containing 2,5-furandicarboxylic acid was carried out with the aim of improving the properties of poly(l-lactic acid) for sustainable packaging applications. The synthetic method followed a novel top-down approach, starting from industrial high-molecular-weight poly(l-lactic acid) (PLLA), which was reacted with 1,5-pentanediol to get hydroxyl-terminated PLLA and then chain-extended with hydroxyl-terminated poly(pentamethylene furanoate) (PPeF-OH). The final copolymer, called P(LLA50PeF50)-CE, was subjected to molecular, structural, and thermal characterization. Tensile and gas permeability tests were also carried out. According to the results obtained, PLLA thermal stability was improved, being the range of processing temperatures widened, and its stiffness and brittleness were decreased, making the new material suitable for the realization of films for flexible packaging. The oxygen permeability of PLLA was decreased by 40% and a similar improvement was measured also for carbon dioxide. P(LLA50PeF50)-CE was found to be completely biodegraded within 60 days of composting treatment. In terms of mechanism, the blocks of PPeF and PLLA were demonstrated to undergo surface erosion and bulk hydrolysis, respectively. In terms of kinetics, PPeF blocks degraded slower than PLLA ones.


Asunto(s)
Compostaje , Embalaje de Alimentos , Embalaje de Alimentos/métodos , Cinética , Poliésteres/química , Polímeros/química
2.
J Am Heart Assoc ; 12(16): e030472, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37581392

RESUMEN

Background Laboratory-based assessments have shown that stroke recovery is heterogeneous between patients and affected domains such as motor and language function. However, laboratory-based assessments are not ecologically valid and do not necessarily reflect patients' daily life performance. Therefore, we aimed to give an innovative view on stroke recovery by profiling daily life performance recovery across domains in patients with early subacute stroke and determine their interrelatedness, taking stroke localization into account. Methods and Results Daily life performance was observed at neurorehabilitation admission and weekly thereafter until discharge, using a scale containing 7 daily life domains. Graphical modeling was applied to investigate the conditional independence between recovery of these domains depending on stroke localization. There were 592 patients analyzed. Four clusters of interrelated domains were identified within the first 6 weeks poststroke. The first cluster included recovery in learning and applying knowledge, general tasks and demands, and domestic life. The second cluster comprised recovery in self-care and general tasks and demands. The third cluster included recovery in mobility and self-care; it incorporated interpersonal interactions and relationships in left supratentorial stroke, and learning and applying knowledge in right supratentorial stroke. The final cluster included only communication recovery. Conclusions Daily life recovery dynamics early poststroke show that although impairments in body functions are anatomically determined, their impact on performance is comparable. Second, some, but by no means all, domains show an interrelated recovery. Domains requiring cognitive abilities are especially interrelated and seem to be essential for concomitant recovery in mobility and domestic life.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Actividades Cotidianas , Autocuidado , Comunicación , Recuperación de la Función
3.
ACS Sustain Chem Eng ; 9(35): 11937-11949, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34513341

RESUMEN

High-molecular-weight poly(butylene 2,4-furanoate) (2,4-PBF), an isomer of well-known poly(butylene 2,5-furanoate) (2,5-PBF), was synthesized through an eco-friendly solvent-free polycondensation process and processed in the form of an amorphous film by compression molding. Molecular characterization was carried out by NMR spectroscopy and GPC analysis, confirming the chemical structure and high polymerization degree. Thermal analyses evidenced a reduction of both glass-to-rubber transition and melting temperatures, as well as a detriment of crystallization capability, for 2,4-PBF with respect to 2,5-PBF. Nevertheless, it was possible to induce crystal phase formation by annealing treatment. Wide-angle X-ray scattering revealed that the crystal lattices developed in the two isomers are distinct from each other. The different isomerism affects also the thermal stability, being 2,4-PBF more thermally inert than 2,5-PBF. Functional properties, such as wettability, mechanical response, and gas barrier capability, were tested on both amorphous and semicrystalline 2,4-PBF films and compared with those of 2,5-PBF. Reduced hydrophilicity was determined for 2,4-isomer, in line with its lower average dipole moment, suggesting better chemical resistance to hydrolysis. Stress-strain tests have evidenced the higher flexibility and toughness of 2,4-PBF with respect to those of 2,5-PBF and the possibility of improving its mechanical resistance by annealing. Finally, the different isomerism deeply affects the gas barrier performance, being the O2- and CO2-transmission rates of 2,4-PBF 50 and 110 times lower, respectively, than those of 2,5-PBF. The gas barrier properties turned out to be outstanding under a dry atmosphere as well as in humid conditions, suggesting the presence of interchain hydrogen bonds. The gas blocking capability decreases after annealing because of the presence of disclination associated with the formation of crystals.

4.
Neuropsychiatr Dis Treat ; 15: 115-125, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30636877

RESUMEN

BACKGROUND: Frequent attenders (FAs), defined as patients reporting a disproportionate number of visits to general practitioners (GPs), may represent up to one-third of GP patients responsible for a high burden of care not always justified by the severity of the medical condition. The aim of this study was to explore sociodemographic and clinical characteristics of FAs of GP in Italy with particular attention to functional impairment. METHODS: A total sample of 75 FAs (defined as individuals who had consulted GPs 15 times or more during 2015) of GPs of three primary care centers (Pisa, Livorno, and Lucca) in Italy were enrolled and assessed by sociodemographic scale, Structured Clinical Interview for DSM-5 (SCID-5), global functioning (Global Assessment of Functioning [GAF]), illness behavior and perceived health (Illness Behavior Inventory), and somatic comorbidity (Cumulative Illness Rating Scale). RESULTS: Most of the sample were females, middle aged, married, or cohabiting, with low levels of education. One-third of FAs was low functioning (LF; GAF score <70), with no differences in the sociodemographic variables. Approximately 70.3% of the patients reported a current SCID diagnosis, in particular, major depressive disorder, somatic symptom disorders, and panic disorder, all being more frequent in LF patients. Half of the patients were taking a psychopharmacological therapy, mostly benzodiazepines (BDZs). CONCLUSION: Most FAs were female with current medical disorders, and LF. All claimed to be worried about their own health and perceived themselves as more impaired also regarding the health perception and social role. LF patients were, or had been more likely to be under psychopharmacological treatment. FAs seem to constitute a special population that should be carefully evaluated for mental disorders and appropriate treatment.

5.
Antioxid Redox Signal ; 8(7-8): 1171-82, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16910765

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity in Western countries. The increased oxidative stress, caused by the release of reactive oxygen and nitrogen species (ROS/RNS) from inflammatory airways cells, contributes to the pathogenesis of the disease. The aim of the present study was to evaluate (a) whether the oxidative imbalance can lead to specific alterations of red blood cells (RBCs) from stable COPD patients; (b) whether treatment with N-acetyl-cysteine (NAC), in widespread use as mucolytic agent in clinical practice, can counteract these effects; and (c) whether an in vitro model represented by the exposure of RBC to ROS/RNS could mimic the in vivo situation. The results obtained clearly indicated that the RBC integrity and function are similarly altered in COPD patients and in ROS/RNS in vitro-treated samples and that NAC administration was capable of counteracting RBC oxidative modifications both in vivo, as detected by clinical and laboratory evaluations, and in vitro. Altogether these results point to RBC oxidative modifications as valuable bioindicators in the clinical management of COPD and indicate that in vitro RBC exposure to ROS/RNS as a useful tool in experimental studies aimed at the comprehension of the pathogenic mechanisms of the redox-associated diseases.


Asunto(s)
Técnicas Biosensibles/métodos , Eritrocitos/fisiología , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Acetilcisteína/administración & dosificación , Acetilcisteína/farmacología , Anciano , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Estudios de Casos y Controles , Forma de la Célula/efectos de los fármacos , Forma de la Célula/fisiología , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Eritrocitos/enzimología , Eritrocitos/ultraestructura , Femenino , Glicoforinas/metabolismo , Humanos , Técnicas In Vitro , Masculino , Metahemoglobina/análisis , Oxidantes/administración & dosificación , Oxidantes/farmacología , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ácido Peroxinitroso/administración & dosificación , Ácido Peroxinitroso/farmacología , Proteínas Tirosina Fosfatasas/análisis
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