Morphine exposure and prematurity affect flash visual evoked potentials in preterm infants.

Objective: The present study aimed to explore first the impact of perinatal risk factors on flash-VEP waves and morphology in a group of preterm infants studied at term equivalent age (TEA). Second, to correlate VEP morphology with neurological outcome at 2 years corrected age (CA). Methods: Infants with a gestational age (GA) at birth <32 weeks, without major brain injury, were enrolled. Multivariate regression analyses were performed, and the models were run separately for each dependent variable N2, P2, N3 latencies and P2 amplitude. Logistic regression was applied to study N4 component (present/absent) and VEP morphology (regular/irregular). The predictors were GA, bronchopulmonary dysplasia (BPD), postmenstrual age at VEP registration, cumulative morphine and fentanyl dose, and painful procedures. Lastly, linear regression models were performed to assess the relation between the Bayley-III cognitive and motor scores at 2 years CA and VEP morphology, in relation to GA, BPD, painful procedures and cumulative morphine dose. Results: Eighty infants were enrolled. Morphine was the predictor of N2 (R2 = 0.09, p = 0.006), P2 (R2 = 0.11, p = 0.002), and N3 (R2 = 0.13, p = 0.003) latencies. Younger GA was associated with lower amplitude (R2 = 0.05, p = 0.029). None of the independent variables predicted the presence of N4 component, nor VEP morphology in the logistic analysis. VEP morphology was not associated with cognitive and motor scores at 2 years. Conclusions: Morphine treatment and prematurity were risk factors for altered VEPs parameters at TEA. In our cohort VEP morphology did not predict neurological outcome. Significance: Morphine administration should be evaluated according to potential risks and benefits, and dosage individually accustomed, according to pain and comfort scores, considering the possible risk for neurodevelopmental impairment.

Favorable subgingival plaque microbiome shifts are associated with clinical treatment for peri-implant diseases.

We performed a longitudinal shotgun metagenomic investigation of the plaque microbiome associated with peri-implant diseases in a cohort of 91 subjects with 320 quality-controlled metagenomes. Through recently improved taxonomic profiling methods, we identified the most discriminative species between healthy and diseased subjects at baseline, evaluated their change over time, and provided evidence that clinical treatment had a positive effect on plaque microbiome composition in patients affected by mucositis and peri-implantitis.

Critical Electrospinning Parameters for Synthesis Control of Stabilized Polyacrylonitrile Nanofibers.

Polyacrylonitrile (PAN) fibers are widely used as precursors in the manufacture of high-conducting and mechanically resistant carbon fibers. The modulation of such fibers is carried out through electrospinning. In this work, we show the production and control of the morphology of nanometric-range PAN fibers for their potential use as precursors for high-electrical-conductivity carbon fibers. PAN samples dissolved in dimethylformamide (DMF) were prepared at 6, 10, and 12% w/w, at 15 and 25 kV. The impact of the rotation of the collector drum at 100, 300, and 500 RPM was also studied. It was found that the percentage of PAN in the solution proportionally affects the diameter of the fibers and that the preparation potential affects the morphology. The rotation speed, when increased, decreases the diameter, and it has a negative impact on the morphology. Fibers prepared with 6% w/w at 15 kV and 500 RPM show 90 nm diameters, the smallest diameter of all the samples.

Unilateral Transient Enhanced SEP during Integrated Multiparameter Neurophysiological Monitoring in a Newborn with Symptomatic Seizure.

During Integrated Multiparametric Neurophysiological Monitoring (IMNA), a newborn with suspected hypoxia at birth and microhaemorrhagic and ischaemic lesions presented some clonic-tonic episodes with specific EEG patterns characterized by rolandic and temporal spikes and the appearance of a unilateral enhanced Somatosensory Evoked Potential (SEP) (10.45 µv). Since the literature does not seem to describe cases of giant SEP in newborns, in this case report, we will discuss the hypotheses underlying this potential. It could be assumed that the ischaemic and haemorrhagic lesions presented by the newborn may have developed as a result of neurotransmitter balance failure. This may be the origin of the EEG picture, which, consequently, could have triggered a potential with high amplitude.

Mediterranean diet diminishes the effects of Crohn's disease and improves its parameters: A systematic review.

BACKGROUND: The pathogenesis and clinical course of Crohn's disease (CD) is influenced by diet. Mediterranean Diet (MD) helps Crohn's patients through many mechanisms. AIMS: This study aimed to evaluate the effect of the MD on CD patients and to evaluate such effect on body parameters. METHODS: PubMed, Science Direct, Web of Science, MEDLINE and Cochrane central library were searched for MD and CD from 2010 to 2020. Included studies met the following criteria: (1) male and female adults (18-75 years) with a confirmed diagnosis of CD; (2) MD as an intervention; (3) original interventional Trial, Cross-Sectional Analysis, or Prospective Cohort Studies. RESULTS: Five studies were included, involving 83,564 participants. A small number of patients with CD fulfilled the P-MDS criteria, the overall scores were low, 4.7 and 4.5 for females and males respectively. Patients with an inactive disease whose adherence to MD was greater, the MD score was negatively correlated with disease activity (p <0.001) and positively with IBDQ (p = 0.008). Twenty-seven percent had a prevalence of impaired adherence to a MD (mMED score = 0-2), giving such a population a risk attributed to 12% for the later CD. Seventy-point reduction in CDAI + decreased fecal CRP / calprotectin, calprotectin <250 mcg/gm or >50% decrease from baseline and hsCRP < 5 mg/L or >50% from baseline. CONCLUSIONS: MD showed anti-inflammatory properties. Adherence to MD was associated with improvement in CD patients and negatively correlated with the disease activity, in addition to a lower risk of developing CD later in life.

Host phenotype classification from human microbiome data is mainly driven by the presence of microbial taxa.

Machine learning-based classification approaches are widely used to predict host phenotypes from microbiome data. Classifiers are typically employed by considering operational taxonomic units or relative abundance profiles as input features. Such types of data are intrinsically sparse, which opens the opportunity to make predictions from the presence/absence rather than the relative abundance of microbial taxa. This also poses the question whether it is the presence rather than the abundance of particular taxa to be relevant for discrimination purposes, an aspect that has been so far overlooked in the literature. In this paper, we aim at filling this gap by performing a meta-analysis on 4,128 publicly available metagenomes associated with multiple case-control studies. At species-level taxonomic resolution, we show that it is the presence rather than the relative abundance of specific microbial taxa to be important when building classification models. Such findings are robust to the choice of the classifier and confirmed by statistical tests applied to identifying differentially abundant/present taxa. Results are further confirmed at coarser taxonomic resolutions and validated on 4,026 additional 16S rRNA samples coming from 30 public case-control studies.

Platinum-Rare Earth Alloy Electrocatalysts for the Oxygen Reduction Reaction: A Brief Overview.

The development of highly active and long-term stable electrocatalysts for the cathode of proton-exchange membrane fuel cells (PEMFC) is a paramount requirement for high performance and durable PEMFC stacks. In this regard, alloying Pt with rare earth metals (REM) has emerged as a promising approach. This short review summarizes and discusses the most relevant advances on Pt-REM alloy electrocatalysts, from bulk polycrystalline surfaces to carbon supported nanostructures, for the oxygen reduction reaction (ORR), and their implementation in PEMFCs, and is a starting point to establish the challenges in synthesis and design and properties goals for novel Pt-REM alloys.

Comparison of Sympathetic Skin Response (SSR) between Electrical and Acoustic Stimuli in a Healthy Pediatric Population.

Data in the literature report that latency and morphology in the cutaneous sympathetic skin response (SSR) do not change according to the type of stimulus delivered, unlike the amplitude which shows greater values in relation to the intensity of the physical impact caused in patient. Since the acoustic stimulus represents a method better tolerated by the pediatric patient, the aim of this study is to evaluate the presence or absence of significant differences in SSR between electrical and acoustic stimuli. The SSR was performed for each child of 18 recruited in this study, deriving from the palm of the hand and the sole of the foot and initially delivering an electrical stimulus at the level of the median nerve at the wrist. Two acoustic stimuli were subsequently delivered with the aid of audiometric headphones. Our results show no significant differences for the amplitude values obtained (p values > 0.05). For the latency there was a statistically significant difference (p-value = 0.001) for the left hand, subsequently not confirmed by the comparison performed between the two sides (p-values = 0.28 and 0.56). If these preliminary data are confirmed by a larger sample, the acoustic stimulus could be introduced in a standardized protocol for performing SSR in pediatric patients.

Immobilisation and Release of Radical Scavengers on Nanoclays for Chemical Reinforcement of Proton Exchange Membranes.

Mechanical and chemical stability of proton exchange membranes are crucial requirements for the development of fuel cells for durable energy conversion. To tackle this challenge, bi-functional nanoclays grafted with amino groups and with embedded radical scavengers, that is, CeO2 nanoparticles were incorporated into Aquivion® ionomer. The composite membranes presented high proton conductivity and increased stability to radical attack compared to non-modified Aquivion membranes, demonstrating the effectiveness of the approach based on radical scavenger immobilisation and release from clay nanocontainers.

Ultra-Thin Platinum Deposits by Surface-Limited Redox Replacement of Tellurium.

Platinum is the most employed electrocatalyst for the reactions taking place in energy converters, such as the oxygen reduction reaction in proton exchange membrane fuel cells, despite being a very low abundant element in the earth's crust and thus extremely expensive. The search for more active electrocatalysts with ultra-low Pt loading is thus a very active field of investigation. Here, surface-limited redox replacement (SLRR) that utilizes the monolayer-limited nature of underpotential deposition (UPD) was used to prepare ultrathin deposits of Pt, using Te as sacrificial metal. Cyclic voltammetry and anodic potentiodynamic scanning experiments have been performed to determine the optimal deposition conditions. Physicochemical and electrochemical characterization of the deposited Pt was carried out. The deposit comprises a series of contiguous Pt islands that form along the grain interfaces of the Au substrate. The electrochemical surface area (ECSA) of the Pt deposit obtained after 5 replacements, estimated to be 18 m²/g, is in agreement with the ECSA of extended surface catalysts on flat surfaces.

Surface-Limited Electrodeposition of Continuous Platinum Networks on Highly Ordered Pyrolytic Graphite.

Continuous thin platinum nanoplatelet networks and thin films were obtained on the flat surface of highly ordered pyrolytic graphite (HOPG) by high overpotential electrodeposition. By increasing the deposition time, the morphology of the Pt deposits can be progressively tuned from isolated nanoplatelets, interconnected nanostructures, and thin large flat islands. The deposition is surface-limited and the thickness of the deposits, equivalent to 5 to 12 Pt monolayers, is not time dependent. The presence of Pt (111) facets is confirmed by High Resolution Transmission Electron Microscopy (HRTEM) and evidence for the early formation of a platinum monolayer is provided by Scanning Transmission Electron Microscopy and Energy Dispersive X-rays Spectroscopy (STEM-EDX) and X-ray Photoelectron Spectroscopy (XPS) analysis. The electroactivity towards the oxygen reduction reaction of the 2D deposits is also assessed, demonstrating their great potential in energy conversion devices where ultra-low loading of Pt via extended surfaces is a reliable strategy.

Electrodeposition of Two-Dimensional Pt Nanostructures on Highly Oriented Pyrolytic Graphite (HOPG): The Effect of Evolved Hydrogen and Chloride Ions.

We discuss the electrodeposition of two-dimensional (2D) Pt-nanostructures on Highly Oriented Pyrolytic Graphite (HOPG) achieved under constant applied potential versus a Pt counter electrode (Eappl = ca. -2.2 V vs. NHE, normal hydrogen electrode). The deposition conditions are discussed in terms of the electrochemical behavior of the electrodeposition precursor (H2PtCl6). We performed cyclic voltammetry (CV) of the electrochemical Pt deposit on HOPG and on Pt substrates to study the relevant phenomena that affect the morphology of Pt deposition. Under conditions where the Pt deposition occurs and H2 evolution is occurring at the diffusion-limited rate (-0.3 V vs. NHE), Pt forms larger structures on the surface of HOPG, and the electrodeposition of Pt is not limited by diffusion. This indicates the need for large overpotentials to direct the 2D growth of Pt. Investigation of the possible effect of Cl- showed that Cl- deposits on the surface of Pt at low overpotentials, but strips from the surface at potentials more positive than the electrodeposition potential. The CV of Pt on HOPG is a strong function of the nature of the surface. We propose that during immersion of HOPG in the electrodeposition solution (3 mM H2PtCl6, 0.5 M NaCl, pH 2.3) Pt islands are formed spontaneously, and these islands drive the growth of the 2D nanostructures. The reducing agents for the spontaneous deposition of Pt from solution are proposed as step edges that get oxidized in the solution. We discuss the possible oxidation reactions for the edge sites.

Strong metal-support interaction improves activity and stability of Pt electrocatalysts on doped metal oxides.

Niobium and antimony doped tin oxide loose-tubes decorated with Pt nanoparticles present outstanding mass activity and stability, exceeding those of a reference carbon-based electrocatalyst. Physico-chemical characterisation and in particular X-ray photoelectron spectroscopy demonstrate that this observation can be ascribed to the strong metal-support interaction promoting electroactivity and Pt anchoring on doped metal oxide supports.

1,2,3-Triazole-Functionalized Polysulfone Synthesis through Microwave-Assisted Copper-Catalyzed Click Chemistry: A Highly Proton Conducting High Temperature Membrane.

Microwave heating holds all the aces regarding development of effective and environmentally friendly methods to perform chemical transformations. Coupling the benefits of microwave-enhanced chemistry with highly reliable copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry paves the way for a rapid and efficient synthesis procedure to afford high performance thermoplastic materials. We describe herein fast and high yielding synthesis of 1,2,3-triazole-functionalized polysulfone through microwave-assisted CuAAC as well as explore their potential as phosphoric acid doped polymer electrolyte membranes (PEM) for high temperature PEM fuel cells. Polymers with various degrees of substitution of the side-chain functionality of 1,4-substituted 1,2,3-triazole with alkyl and aryl pendant structures are prepared by sequential chloromethylation, azidation, and microwave-assisted CuAAC using a range of alkynes (1-pentyne, 1-nonyne, and phenylacetylene). The completeness of reaction at each step and the purity of the clicked polymers were confirmed by (1)H-(13)C NMR, DOSY-NMR and FTIR-ATR spectroscopies. The thermal and thermochemical properties of the modified polymers were characterized by differential scanning calorimetry and thermogravimetric analysis coupled with mass spectroscopy (TG-MS), respectively. TG-MS analysis demonstrated that the commencement of the thermal degradation takes place with the decomposition of the triazole ring while its substituents have critical influence on the initiation temperature. Polysulfone functionalized with 4-phenyl-1,2,3-triazole demonstrates significantly higher Tg, Td, and elastic modulus than the ones bearing 4-propyl-1,2,3-triazole and 4-heptyl-1,2,3-triazole groups. After doping with phosphoric acid, the functionalized polymers with acid doping level of 5 show promising performance with high proton conductivity in anhydrous conditions (in the range of 27-35 mS/cm) and satisfactorily high elastic modulus (in the range of 332-349 MPa).

Nickel Based Electrospun Materials with Tuned Morphology and Composition.

Nickel is set to play a crucial role to substitute the less-abundant platinum in clean electrochemical energy conversion and storage devices and catalysis. The controlled design of Ni nanomaterials is essential to fine-tune their properties to match these applications. A systematic study of electrospinning and thermal post-treatment parameters has been performed to synthesize Ni materials and tune their morphology (fibers, ribbons, and sponge-like structures) and composition (metallic Ni, NiO, Ni/C, Ni3N and their combinations). The obtained Ni-based spun materials have been characterized by scanning and transmission electron microscopy, X-ray diffraction and thermogravimetric analysis. The possibility of upscaling and the versatility of electrospinning open the way to large-scale production of Ni nanostructures, as well as bi- and multi-metal systems for widened applications.

Negligible degradation upon in situ voltage cycling of a PEMFC using an electrospun niobium-doped tin oxide supported Pt cathode.

Novel platinum-catalysed, corrosion-resistant, loose-tube-structured electrocatalysts for proton exchange membrane fuel cells have been obtained using single-needle electrospinning associated with a microwave-assisted polyol method. Monodisperse platinum particles supported on Nb-SnO2 demonstrated higher electrochemical stability than conventional Pt/C electrodes during ex situ potential cycling and comparable activity in the oxygen reduction reaction. In situ fuel cell operation under accelerated stress test conditions of a membrane electrode assembly elaborated using a Pt/C anode and Pt/Nb-SnO2 cathode confirmed that the voltage loss is significantly lower for the novel cathode than for an MEA prepared using conventional Pt/C supported electrocatalysts. Furthermore, the Nb-SnO2 stabilised the supported platinum nanoparticles against dissolution, migration and reprecipitation in the membrane. Pt/Nb-SnO2 loose-tubes constitute a mitigation strategy for two known degradation mechanisms in PEMFC: corrosion of the carbon support at the cathode, and dissolution of Pt at high cell voltages.

Mesoporous nanostructured Nb-doped titanium dioxide microsphere catalyst supports for PEM fuel cell electrodes.

Crystalline microspheres of Nb-doped TiO(2) with a high specific surface area were synthesized using a templating method exploiting ionic interactions between nascent inorganic components and an ionomer template. The microspheres exhibit a porosity gradient, with a meso-macroporous kernel, and a mesoporous shell. The material has been investigated as cathode electrocatalyst support for polymer electrolyte membrane (PEM) fuel cells. A uniform dispersion of Pt particles on the Nb-doped TiO(2) support was obtained using a microwave method, and the electrochemical properties assessed by cyclic voltammetry. Nb-TiO(2) supported Pt demonstrated very high stability, as after 1000 voltammetric cycles, 85% of the electroactive Pt area remained compared to 47% in the case of commercial Pt on carbon. For the oxygen reduction reaction (ORR), which takes place at the cathode, the highest stability was again obtained with the Nb-doped titania-based material even though the mass activity calculated at 0.9 V vs RHE was slightly lower. The microspherical structured and mesoporous Nb-doped TiO(2) is an alternative support to carbon for PEM fuel cells.

Single step elaboration of size-tuned Pt loaded titania nanofibres.

Conductive titania nanofibres supporting Pt nanoparticles were synthesised in a one-pot method based on the electrospinning technique. The dimensions of both the oxide fibres and platinum particles were tuneable, leading to versatile nanomaterials with possible applications as electrodes for energy conversion devices.