Search results for "Beni culturali"
showing 10 items of 1017 documents
α-casein micelles-membranes interaction: Flower-like lipid protein coaggregates formation
2022
Background: Environmental conditions regulate the association/aggregation states of proteins and their action in cellular compartments. Analysing protein behaviour in presence of lipid membranes is fundamental for the comprehension of many functional and dysfunctional processes. Here, we present an experimental study on the interaction between model membranes and α-casein. α-casein is the major component of milk proteins and it is recognised to play a key role in performing biological functions. The conformational properties of this protein and its capability to form supramolecular structures, like micelles or irreversible aggregates, are key effectors in functional and pathological effects…
Ingestion of plastic and non-plastic microfibers by farmed gilthead sea bream (Sparus aurata) and common carp (Cyprinus carpio) at different life sta…
2021
Environmental pollution by plastic particles is of major global concern, as a potential threat to aquatic organisms and ecosystems. The accumulation of microplastics in freshwater and marine environments has strong ecological implications due to their long persistence, potential toxicity, and ability to adsorb other pollutants, acting as vectors of pathogens. Nevertheless, while the number of studies on the presence of microplastics in the wild fish increased, less attention has been paid to the farmed fish species. Here, we investigated the occurrence of microparticles in the digestive tracts of Sparus aurata and Cyprinus carpio at different life stages and reared by an intensive and semi-…
Nile Red lifetime reveals microplastic identity
2020
Microplastic pollution is recognized as a worldwide environmental problem. The increasing daily use and release of plastics into the environment have led to the accumulation of fragmented microplastics, with potentially awful consequences for the environment, and animal and human health. The detection and identification of microplastics are of utmost importance, but available methods are still limited. In this work, a new approach is presented for the analysis of microplastics based on hydrophobic fluorescence staining with Nile Red, using spectrally resolved confocal fluorescence microscopy and fluorescence lifetime imaging microscopy (FLIM). Significant differences were observed in the em…
Identification of microplastics using 4‐dimethylamino‐4′‐nitrostilbene solvatochromic fluorescence
2021
In this work, we introduce the use of 4-dimethylamino-4'-nitrostilbene (DANS) fluorescent dye for applications in the detection and analysis of microplastics, an impendent source of pollution made of synthetic organic polymers with a size varying from less than 5 mm to nanometer scale. The use of this dye revealed itself as a versatile, fast and sensitive tool for readily discriminate microplastics in water environment. The experimental evidences herein presented demonstrate that DANS efficiently absorbs into a variety of polymers constituting microplastics, and its solvatochromic properties lead to a positive shift of the fluorescence emission spectrum according to the polarity of the poly…
Comparison of two portable solid state detectors with an improved collimation and alignment device for mammographic x-ray spectroscopy.
2006
We describe a portable system for mammographic x-ray spectroscopy, based on a 2 X 2 X 1 mm3 cadmium telluride (CdTe) solid state detector, that is greatly improved over a similar system based on a 3 X 3 X 2 mm3 cadmium zinc telluride (CZT) solid state detector evaluated in an earlier work. The CdTe system utilized new pinhole collimators and an alignment device that facilitated measurement of mammographic x-ray spectra. Mammographic x-ray spectra acquired by each system were comparable. Half value layer measurements obtained using an ion chamber agreed closely with those derived from the x-ray spectra measured by either detector. The faster electronics and other features of the CdTe detecto…
Vigilanza (art. 103)
2000
Il saggio esamina il potere di vigilanza del Ministero dei beni culturali secondo l'art. 103 del Testo unico dei beni culturali e ambientali del 1999.
Probing in cell protein structural changes with time-resolved X-ray scattering
2012
International audience; Investigating protein structural changes inside the cell is a major goal in molecular biology. Here we show that time-resolved wide-angle X-ray scattering is a valuable tool for this purpose. Hemoglobin has been chosen as a model system and its tertiary and quaternary conformational changes following laser flash-photolysis have been tracked in intact red blood cells with nanosecond time resolution.
The route to protein aggregate superstructures: Particulates and amyloid-like spherulites.
2015
AbstractDepending on external conditions, native proteins may change their structure and undergo different association routes leading to a large scale polymorphism of the aggregates. This feature has been widely observed but is not fully understood yet. This review focuses on morphologies, physico-chemical properties and mechanisms of formation of amyloid structures and protein superstructures. In particular, the main focus will be on protein particulates and amyloid-like spherulites, briefly summarizing possible experimental methods of analysis. Moreover, we will highlight the role of protein conformational changes and dominant forces in driving association together with their connection w…
The Monod-Wyman-Changeux allosteric model accounts for the quaternary transition dynamics in wild type and a recombinant mutant human hemoglobin
2012
International audience; The acknowledged success of the Monod-Wyman-Changeux (MWC) allosteric model stems from its efficacy in accounting for the functional behavior of many complex proteins starting with hemoglobin (the paradigmatic case) and extending to channels and receptors. The kinetic aspects of the allosteric model, however, have been often neglected, with the exception of hemoglobin and a few other proteins where conformational relaxations can be triggered by a short and intense laser pulse, and monitored by time-resolved optical spectroscopy. Only recently the application of time-resolved wide-angle X-ray scattering (TR-WAXS), a direct structurally sensitive technique, unveiled th…
The Tempered Polymerization of Human Neuroserpin
2012
Neuroserpin, a member of the serpin protein superfamily, is an inhibitor of proteolytic activity that is involved in pathologies such as ischemia, Alzheimer's disease, and Familial Encephalopathy with Neuroserpin Inclusion Bodies (FENIB). The latter belongs to a class of conformational diseases, known as serpinopathies, which are related to the aberrant polymerization of serpin mutants. Neuroserpin is known to polymerize, even in its wild type form, under thermal stress. Here, we study the mechanism of neuroserpin polymerization over a wide range of temperatures by different techniques. Our experiments show how the onset of polymerization is dependent on the formation of an intermediate mon…