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A Plasma-Enhanced Chemical Vapor Deposition was chosen in order to deposit an organic thin film on polyethylene terephthalate monofilament to increase its adhesion with the rubber compound in a tire. The aim of the work is to find an alternative “green” method to the classical chemical dipping with Resorcinol Formaldehyde Latex: plasma treatments are environmentally friendly and easy to use. 2-isoprepenyl-2-oxazoline (2-iox) was employed as precursor and the treatments were performed in a vacuum system, both in a continuous regime and a pulsed regime. Initially, the coatings were deposited on polyethylene terephthalate sheets to study the wettability (by the measurement of contact angle) and the thickness (by profilometer) of the plasma polymer. The chemical characterization was investigated by Infrared and X-ray Photoelectron spectroscopies. Finally, the adhesion of the polyethylene terephthalate sheets was measured by Peel Test, using the coating as adhesive and as a pre-dip. The measurement of the peel force made it possible to optimize the plasma parameters that were applied on the monofilament. The adhesion was estimated by the measure of the extraction force and the evaluation of the coverage compared with those of the classical chemical treatment Resorcinol Formaldehyde Latex.

Medical-grade poly(methyl methacrylate) (PMMA) is widely employed in the fabrication of intraocular lenses (IOLs), but suffers from opacification, a postoperative complication that leads to the failure of the implanted intraocular lenses. The opacification occurs when inorganic-based deposits accumulate on the surface of the IOL and are prevalent in hydrophilic materials. Here, the surface of medical-gradePMMAhas been fluorinated by sulphur hexafluoride (SF6) plasma treatment to increase surface hydrophobicity thus improving the material lifetime in optical applications. Hydrophobic properties of the treated PMMA were investigated by means of contact angle measurements, while chemical modification was assessed by X-ray Photoelectron Spectroscopy (XPS) and Attenuated Total Reflectance Fourier Transform Infrared (ATR/FTIR) spectroscopy. Surface morphological changes due to possible etching effects were investigated by Atomic Force Microscopy (AFM). The transparency of the treated PMMA was assessed by UV/VIS spectroscopy. Finally, the influence of the plasma treatment on the inorganic salts deposition was investigated by immersion in Simulated Aqueous Humour (SAH), followed by XPS analysis. The modified samples showed less deposition on the surface than the unmodified sample, moreover, a decrease of the transmittance in the UV-violet range (300-430 nm) was detected, open the possibility of interesting applications of this treatment for the creation of a UV filter in ophthalmic optical devices.

Post-transplant lymphoproliferative disorders (PTLD) represent a severe complication in transplanted patients and Epstein-Barr Virus (EBV) is the main driver. Besides immunodepression, immune activation/chronic inflammation play an important role in both virus reactivation and expansion of EBV-positive B cells. The aim of this study was to assess the impact of immunosuppressive strategies on factors involved in the PTLD's pathogenesis. 124 kidney transplanted patients were enrolled in this study: 71 were treated with mycophenolic acid (MPA) and 53 treated with mTOR inhibitor (mTORi), both in combination with different doses of calcineurin inhibitor. At the time of the transplant (T0), profile of inflammation/immune activation and immune senescence didn't differ between the two groups, but after one year of treatment (T1) markers were significantly higher in MPA-treated patients; their immunosenescence process was supported by the greater erosion of telomeres despite their younger age. Percentages of activated B cells and levels of EBV-DNA significantly increased in MPA-treated patients, and at T1 were significantly higher in MPA- than in mTORi-treated patients. Overall, these findings indicate that mTOR inhibitors constrain the inflammation/immune activation and senescence status, thus reducing the expansion of EBV-infected B cells and the risk of virus-associated PTLD in kidney transplant recipients. © 2019 The Authors

Background: In southern Europe, the risk of cancer in patients with end-stage kidney disease receiving dialysis has not been well quantified. The aim of this study was to assess the overall pattern of risk for de novo malignancies (DNMs) among dialysis patients in the Friuli Venezia Giulia region, north-eastern Italy. Methods: A population-based cohort study among 3407 dialysis patients was conducted through a record linkage between local healthcare databases and the cancer registry (1998-2013). Person-years (PYs) were calculated from 30 days after the date of first dialysis to the date of DNM diagnosis, kidney transplant, death, last follow-up or December 31, 2013, whichever came first. The risk of DNM, as compared to the general population, was estimated using standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). Results: During 10,798 PYs, 357 DNMs were diagnosed in 330 dialysis patients. A higher than expected risk of 1.3-fold was found for all DNMs combined (95% CI: 1.15-1.43). The risk was particularly high in younger dialysis patients (SIR = 1.88, 95% CI: 1.42-2.45 for age 40-59 years), and it decreased with age. Moreover, significantly increased DNM risks emerged during the first 3 years since dialysis initiation, especially within the first year (SIR = 8.52, 95% CI: 6.89-10.41). Elevated excess risks were observed for kidney (SIR = 3.18; 95% CI: 2.06-4.69), skin non-melanoma (SIR = 1.81, 95% CI: 1.46-2.22), oral cavity (SIR = 2.42, 95% CI: 1.36-4.00), and Kaposi's sarcoma (SIR = 10.29, 95% CI: 1.25-37.16). Conclusions: The elevated risk for DNM herein documented suggest the need to implement a targeted approach to cancer prevention and control in dialysis patients.

We performed atmospheric pressure plasma treatments of wool/cashmere (15/85%) textiles with a dielectric barrier discharge (DBD) in nitrogen. The chemical properties of the plasma treated samples were investigated with attenuated total reflectance Fourier transform infrared (FTIR/ATR) spectroscopy, X-ray photoelectron microscopy (XPS), and fatty acid gas chromatographic analysis. Changes in mechanical properties and tactile performance of textiles after the plasma treatment were determined using the KES-F system. The analyses reveal significant surface modification of the treated fabrics, which enhances their surface wettability.

Thin coatings were deposited by means of low pressure plasma polymerization of 2-isopropenyl-2-oxazoline (2-IOX). Depositions were performed in the pulsed mode, exploiting the carbon-carbon double bond of the monomer, in order to maximize the retention of oxazoline rings in the coatings. The wettability of the thin films was assessed by water contact angle measurements, while their stability was investigated by immersion in different aqueous environments (Phosphate Buffer Saline (PBS) at 37 °C and aqueous solutions with different pH) and was found to be dependent on the deposition conditions. Chemical characterization of the coatings was performed by means of Attenuated Total Reflectance Fourier Transform Infrared (FTIR/ATR) spectroscopy, Nuclear Magnetic Resonance (1H NMR) spectroscopy and Gel Permeation Chromatography (GPC). All these techniques allowed to assess the retention of oxazoline ring, which can be exploited through reaction of the plasma deposited coatings with carboxylic acid groups. To this end, reactions with poly(acrylic acid) in different conditions (temperature, reaction time) were investigated

The aim of the present research was to address somatosensory high frequency oscillations (400–800 Hz) in healthy children and adolescents in comparison with healthy adults. We recorded somatosensory evoked potentials following median nerve stimulation in nineteen resting healthy children/adolescents and in nineteen resting healthy adults with eyes closed. We administered six consecutive stimulation blocks (500 sweeps each). The presynaptic component of high frequency oscillations amplitudes was smaller in healthy children/adolescents than in healthy adults (no difference between groups was found as far as the postsynaptic component was concerned). Healthy children/adolescents had smaller presynaptic component than the postsynaptic one (the postsynaptic component amplitude was 145% of the presynaptic one), while healthy adults showed the opposite (reduction of the postsynaptic component to 80% of the presynaptic one). No habituation phenomena concerning high frequency oscillation amplitudes were registered in neither healthy children/adolescents nor healthy adults. These findings suggest that healthy children/adolescents present with significantly different pattern of somatosensory high frequency oscillations compared with healthy adults’ ones. This different pattern is reasonably expression of higher cortical excitability of the developing brain cortex.

Fluorocarbon coatings were deposited by plasma polymerization of 1H,1H,2H-perfluoro-1-decene (HDFD). Chemical and morphological characterization of coatings obtained from different process parameters was performed by means of Attenuated Total Reflectance Fourier Transform Infrared (FTIR/ATR) spectroscopy, Energy Dispersive X-Ray analysis (EDX) and Atomic Force Microscopy (AFM). Hydro- and oleo-repellency were evaluated by contact angle measurements with different liquids. Optical properties were investigated by acquiring the transmittance spectra in the region 300–900 nm. Finally, evaluation of the mechanical properties was performed by means AFM nanoindentation. By increasing the Yasuda factor (the energy consumed per mass of monomer), coatings with lower retention of fluorocarbon chains were obtained. The F/C ratio, measured by means of EDX analysis, decreased from 0.85 for coatings deposited at 10 W to 0.69 for coatings deposited at 100 W. As a consequence of the lower retention of fluorocarbon chains, coatings deposited at high Yasuda factors displayed lower hydro- and oleo-repellency. In addition, these coatings contains large amount of unsaturated groups ([Formula presented], [Formula presented], ...), as assessed by ATR analysis. This led to a lower transparency, due to radiation absorption in the visible region. On the other hand, the mechanical properties (and hence the durability) of the coatings increased with the energy consumed per monomer molecule.

Poly(2-ethyl-2-oxazoline) thin coatings were deposited on different substrates by means of low pressure plasma polymerization. The stability of the thin films was evaluated by immersion in different aqueous environments (Phosphate Buffer Saline (PBS) at 37 °C, sodium dodecyl sulfate (SDS) solutions, aqueous solutions with different pH) and was found to be dependent on the deposition conditions. Chemical characterization of the coatings deposited with different process parameters was performed by means of Attenuated Total Reflectance Fourier Transform Infrared (FTIR/ATR) spectroscopy and Nuclear Magnetic Resonance (NMR) spectroscopy. Partial retention of the oxazoline ring was assessed also for the stable coatings. Noteworthy, the coatings displayed an intrinsic fluorescence with an emission maximum around 534–542 nm. The reactivity of the plasma deposited coatings towards carboxylic, amino- and hydroxyl groups was investigated through selected reactions with poly(acrylic acid), amino-terminated polyethylene glycol and zonyl FSO-100 fluorosurfactant. Results indicate strong reactivity with COOH groups, probably as a consequence of the partial retention of the oxazoline ring. As a result, it is suggested that stable coatings can be exploited for the covalent immobilization of COOH-containing proteins or biomolecules, opening a wide range of potential applications.

We describe the hydro- and oleo-repellent modification of pure cashmere and wool/nylon textiles by means of an atmospheric pressure plasma treatment followed by an impregnation with a fluorocarbon resin. Plasma treatments of both fabrics were realized with a dielectric barrier discharge (DBD) in humid air (air/water vapour mixtures), while the finishing process was performed in a foulard system, with an aqueous dispersion of a commercial fluorocarbon resin (FCR). A deep characterization allowed us to study the wettability, the surface morphologies and the chemical composition of the modified textiles. The chemical properties of the untreated and of the modified fabrics were investigated with X-ray photoelectron spectroscopy (XPS). SEM analyses coupled with a complete energy dispersive X-ray system (EDX) allowed us to investigate the distribution and the uniformity of the FCR on the fibres of the coated fabrics. Results show the importance of the plasma activation step to obtain a uniform coverage of the fibres with the FCR, which enhances the hydro- and the oleo-repellent properties of the modified fabrics.

This work reports a detailed experimental study of the plasma properties in low pressure RF discharges in hydrogen peroxide and a comparison with argon under the same operating conditions. H2O2 plasmas have been proposed for sterilization purposes. Electrical properties of the discharge were shown to be similar, as for the RF and DC voltages of the driving electrode. Bulk plasma volume remains stable, concentrated in an almost cylindrical region between the two facing electrodes. It was found that the electron temperature is almost uniform across the plasma and independent of the power level. This is higher than in argon discharges: T e = 4.6 ± 0.9 eV versus T e = 3.3 ± 1.1 eV. The plasma density increases almost linearly with the power level and a substantial negative ion component has been ruled out in hydrogen peroxide. Dissociation in the plasma gas phase was revealed by atomic hydrogen and hydroxyl radical emission in the discharge spectra. Emission from hydroxyl and atomic oxygen demonstrates that oxidizing radicals are produced by hydrogen peroxide discharges, revealing its usefulness for plasma processing other than sterilization, for instance to increase polymer film surface energy. On the other hand, argon could be considered as a candidate for the sterilization purposes due to the intense production of UV radiation.

The consolidation of samples of waterlogged wood was attempted using allylated lignin as cross-linker and compatibilizer in the silicone oil conservative treatment. During the curing of the composite, allylated lignin was reacted with a poly(dimethylsiloxane) hydride terminated on both the ends of the silicone chain through a hydrosilylation reaction in the presence of the Karstedt’s catalyst. Three lignin–silicone hybrids were prepared using different allyl/hydride group ratios. Preliminary wood consolidation was thus accomplished treating pieces of wood with lignin–silicone hybrids prepared in situ with silicone and allylated lignin in different concentrations in the presence of the Karstedt’s catalyst. IR and SEM-EDX analysis proved that the growth of the silicone–lignin polymer was easier within the external layers. In addition, water uptake tests and contact angle measurements were performed on consolidated wood samples to evaluate the extent of hydrophobicity.

AIM: To compare neurophysiological parameters of central nervous system excitability in healthy children/adolescents with those of healthy adults. METHOD: Two experimental protocols were used in 19 healthy children/adolescents (10 males and 9 females, mean age 9y 11mo [SD 2y 9mo], range 5-15y) and 19 healthy adults (8 males and 11 females, mean age 36y 6mo [SD 7y 9mo], range 27-51y). First, we administered repetitive trains of innocuous electrical stimulation of the median nerve and analysed habituation (progressive attenuation) of the cervical and cortical responses. Second, we administered several blocks of two closely timed electrical innocuous stimuli of the median nerve (with interstimulus intervals set at 5, 10, and 20ms in each block) and analysed the recovery index (the percentage of the response to the second stimulus with respect to that to the first). RESULTS: Clear-cut neurophysiological signs of cortical hyper-excitability were found in children/adolescents but not in adults. In contrast with the adults, the children/adolescents did not attenuate cortical responses to repetitive stimulation, and presented with extremely shortened recovery cycle. At baseline, both groups presented with comparable cortical responses. INTERPRETATION: Healthy children/adolescents present cortical hyper-excitability compared with healthy adults. These findings agree with previous findings that show an overall imbalance of excitatory and inhibitory neuronal and neurochemical mechanisms in favour of excitatory ones, in the healthy developing cerebral cortex.