255 research outputs found

    Flunisolide Decreases Exhaled Nitric Oxide and Nitrotyrosine Levels in Asthmatic Children

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    Background. Exhaled nitric oxide (FeNO) has been reported to be elevated in the oxidative stress involved in asthmatic patients, and the reaction of nitric oxide (NO) with superoxide anions results in the formation of nitrotyrosine. The purpose of this study was to investigate the effect of inhaled steroid treatment on nitrotyrosine levels collected by exhaled breath condensate (EBC) and on FeNO. Methods. This was a single-blind placebo-controlled study. The lung function, FeNO, and nitrotyrosine levels were evaluated in 10 asthmatic children. Results. The nitrotyrosine levels were stable during the placebo period (T0 = 1.16 ng/ml versus T1 = 1.05 ng/ml; NS.), whereas they decreased after the treatment with flunisolide (T2 = 1.14 ng/ml versus T3 = 0.88 ng/ml; P < .001). No significant reduction in FeNO levels was observed after placebo treatment (T0 = 38.4 ppb versus T1 = 34.7 ppb, NS.). In contrast, FeNO values decreased significantly being at T3 = 14.9 ppb (T1 versus T3; P = .024). Conclusions. This study shows that corticosteroid treatment reduces nitrotyrosine levels in EBC of asthmatic subjects

    Applicability of Confocal Raman Microscopy to Observe Microstructural Modifications of Cream Cheeses as Influenced by Freezing

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    Confocal Raman microscopy is a promising technique to derive information about microstructure, with minimal sample disruption. Raman emission bands are highly specific to molecular structure and with Raman spectroscopy it is thus possible to observe different classes of molecules in situ, in complex food matrices, without employing fluorescent dyes. In this work confocal Raman microscopy was employed to observe microstructural changes occurring after freezing and thawing in high-moisture cheeses, and the observations were compared to those obtained with confocal laser scanning microscopy. Two commercially available cream cheese products were imaged with both microscopy techniques. The lower resolution (1 µm/pixel) of confocal Raman microscopy prevented the observation of particles smaller than 1 µm that may be part of the structure (e.g., sugars). With confocal Raman microscopy it was possible to identify and map the large water domains formed during freezing and thawing in high-moisture cream cheese. The results were supported also by low resolution NMR analysis. NMR and Raman microscopy are complementary techniques that can be employed to distinguish between the two different commercial formulations, and different destabilization levels

    Monitoraggio biologico ed esposizione a silice: applicazione di nuovi indicatori di dose e di effetto

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    In 16 addetti alla produzione di marmi ricomposti è stato misurato Si-CAE, è stata eseguita una spirometria e sono stati dosati 8oxoGua, 8oxoGuo, 8oxodGuo, SP-A, SP-D, CC16 e HO-1. Si sono osservati valori spirometrici (FVC e FEV1) più bassi nei lavoratori rispetto ai controlli. Nei lavoratori abbiamo osservato livelli più elevati dei seguenti marcatori: Si-CAE, 8oxoGuo ed espressione di HO-1. Lo studio evidenzia che l’esposizione a silice può aumentare i livelli di Si-CAE, che può essere usato per stimare la dose al bersaglio. Infine si evidenziavano aspecifiche alterazioni spirometriche ed un aumento di biomarcatori d’effetto

    In-vivo vascular application via ultra-fast bioprinting for future 5D personalised nanomedicine

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    The design of 3D complex structures enables new correlation studies between the engineering parameters and the biological activity. Moreover, additive manufacturing technology could revolutionise the personalised medical pre-operative management due to its possibility to interplay with computer tomography. Here we present a method based on rapid freeze prototyping (RFP) 3D printer, reconstruction cutting, nano dry formulation, fast freeze gelation, disinfection and partial processes for the 5D digital models functionalisation. We elaborated the high-resolution computer tomography scan derived from a complex human peripheral artery and we reconstructed the 3D model of the vessel in order to obtain and verify the additive manufacturing processes. Then, based on the drug-eluting balloon selected for the percutaneous intervention, we reconstructed the biocompatible eluting-freeform coating containing 40\u2009nm fluorescent nanoparticles (NPs) by means of RFP printer and we tested the in-vivo feasibility. We introduced the NPs-loaded 5D device in a rat's vena cava. The coating dissolved in a few minutes releasing NPs which were rapidly absorbed in vascular smooth muscle cell (VSMC) and human umbilical vein endothelial cell (HUVEC) in-vitro. We developed 5D high-resolution self-dissolving devices incorporating NPs with the perspective to apply this method to the personalised medicine

    Titanium dioxide nanoparticles promote arrhythmias via a direct interaction with rat cardiac tissue

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    BackgroundIn light of recent developments in nanotechnologies, interest is growing to better comprehend the interaction of nanoparticles with body tissues, in particular within the cardiovascular system. Attention has recently focused on the link between environmental pollution and cardiovascular diseases. Nanoparticles <50 nm in size are known to pass the alveolar¿pulmonary barrier, enter into bloodstream and induce inflammation, but the direct pathogenic mechanisms still need to be evaluated. We thus focused our attention on titanium dioxide (TiO2) nanoparticles, the most diffuse nanomaterial in polluted environments and one generally considered inert for the human body.MethodsWe conducted functional studies on isolated adult rat cardiomyocytes exposed acutely in vitro to TiO2 and on healthy rats administered a single dose of 2 mg/Kg TiO2 NPs via the trachea. Transmission electron microscopy was used to verify the actual presence of TiO2 nanoparticles within cardiac tissue, toxicological assays were used to assess lipid peroxidation and DNA tissue damage, and an in silico method was used to model the effect on action potential.ResultsVentricular myocytes exposed in vitro to TiO2 had significantly reduced action potential duration, impairment of sarcomere shortening and decreased stability of resting membrane potential. In vivo, a single intra-tracheal administration of saline solution containing TiO2 nanoparticles increased cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. Computational modeling of ventricular action potential indicated that a membrane leakage could account for the nanoparticle-induced effects measured on real cardiomyocytes.ConclusionsAcute exposure to TiO2 nanoparticles acutely alters cardiac excitability and increases the likelihood of arrhythmic events

    Apparent slip and drag reduction for the flow over superhydrophobic and lubricant-impregnated surfaces

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    The motion of a liquid above textured surfaces, impregnated with either a gas or a lubricant oil, is considered by homogenizing the microscopic near-wall flow to obtain protrusion heights (or Navier slip lengths), which can then be used in (macroscopic) direct numerical simulations of turbulence. The microstructure of the wall consists in longitudinally aligned ridges; this renders the small-scale Stokes problem amenable to decoupling into two problems, solved by the boundary element method with full account of the deformation of the liquid-lubricant interface, finally yielding two different protrusion heights, a longitudinal and a transverse one, respectively h|| and h. Such heights are then employed in direct numerical simulations of the turbulent flow in a channel bounded by superhydrophobic or lubricant-impregnated walls, demonstrating the reduction in skin-friction drag which can be achieved with the rise in protrusion height difference, \u394h=h||-h. The results are in good agreement with an analytical approximation, provided \u394h+ (\u394h scaled in wall units) remains below 2 and the protrusion heights small in magnitude
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