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To estimate the incremental yield of detecting pathogenic or likely pathogenic diagnostic genetic variants (DGV) by whole exome sequencing (WES) over standard karyotype and chromosomal microarray (CMA) analyses in fetuses with isolated increased nuchal translucency (NT) and normal fetal anatomy at the time of 11-14 weeks scan. Medline and Embase databases were searched. Inclusion criteria were fetuses with NT >95th percentile, normal karyotype and CMA and no associated structural anomalies at the time of the 11-14 weeks scan. The primary outcome was to estimate the incremental yield of detecting pathogenic or likely pathogenic genetic variants by WES over standard karyotype and CMA analyses in fetuses with isolated increased nuchal translucency. The secondary outcomes were the detection of a genetic variant of unknown significance. Sub-analysis according to different NT cutoffs (between 3.0 and 5.5 mm and > 5.5 mm) and considering fetuses with isolated NT in which fetal anatomy was confirmed to be normal at the anomaly scan were also performed. Random effects model meta-analyses of proportion were used to analyze the data. Eight articles (324 fetuses) were included in the systematic review. Of the fetuses with negative standard karyotype and CMA analysis, the 8.07% (95% CI 5.4–11.3) had pathogenic or likely pathogenic genetic variants detected exclusively by WES. When stratifying the analysis according to NT cutoffs, genetic anomalies detected exclusively at WES analysis were found in 44.70% (95% CI 26.8–63.4) of fetuses with NT between 3.0 mm and 5.5 mm and 55.3% (95% CI 36.6–73.2) in those fetuses with NT >5.5 mm and positive WES results. The 7.84% (95% CI 1.6–18.2) had variants of unknown significance identified by WES. When considering fetuses with isolated increased NT and normal fetal anatomy at the anomaly scan, the rate of pathogenic or likely pathogenic genetic variants detected by WES was 3.87% (95% CI 1.6–7.1), while variants of unknown significance were detected in 4.27% (95% CI 2.2–7.0) of cases. Pathogenic and likely pathogenic genetic variants detected by WES are present in a significant proportion of fetuses with increased NT but normal standard karyotype and CMA analysis, also when no anomalies are detected at the anomaly scan. Further large studies sharing objective protocols of imaging assessment are needed to confirm these findings and to elucidate which gene panels should be assessed in fetuses with isolated increased NT to rule out associated genetic anomalies, which may potentially impact post-natal outcomes.

As the advantageous properties of nanoparticles (NPs) often emerge only when appropriate coupling and exchange phenomena between the NPs can take place, the control of the inter-particle distance, regular ordering, and location of the nanoparticles onto solid supports is a critical issue. A robust method to control the spatial organization of NPs onto solid supports, based on the use of self-assembling di-block copolymers (BCPs) as structure-guiding material, is reported. Two different polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) BCPs, characterized by a different PS volume fraction, were used as matrices for the fabrication of nanocomposite thin films with cylindrical and lamellar morphologies controlled at the nanoscale. Selective inclusion of surface functionalized gold (Au) and zinc oxide (ZnO) NPs of appropriate size in the PS nanodomains was achieved from dispersions of the BCPs and NPs in a common solvent. The orientation of the BCPs cylinder and lamellar nanodomains in spin-coated thin films was controlled by solvent and thermal annealing protocols, coupled with techniques of surface neutralization.

It is still problematic to define a direct relationship between specific properties of a nanostructured surface (e.g., wettability) and its morphology. Not surprisingly, scientists continue to explore en masse the cut-and-try method. In this work, new insights are presented into the correlation of functional properties of the complex nanocomposites with their morphological characteristics. Using polyethylene-terephthalate (PET) as a model material due to its importance and wide use in experiments, super-hydrophilic nanocomposites amenable to be used in a variety of industrial applications are first developed, by exposing PET samples to oxygen plasma under controlled conditions. The morphology of the surfaces is confirmed using AFM and SEM techniques, and wettability in air and its oleophobic properties in water using contact angle and roll-off measurements. Next, different analytical tools such as Minkowski connectivity (Euler-Poincaré characteristic), Hough distributions and 2D FFT are applied to study ordering, connectivity, and fractal characteristics of the samples. It is concluded that fractal dimension, along with ordering and connectivity, are among the major characteristics of the nanocomposite that determine many important physical and chemical properties of the functional nanomaterials, and the fractal dimension could be a target morphological feature to inform the design of fabrication technology.

Magnetoresistive (MR) biosensors combine distinctive features such as small size, low cost, good sensitivity, and propensity to be arrayed to perform multiplexed analysis. Magnetic nanoparticles (MNPs) are the ideal target for this platform, especially if modified not only to overcome their intrinsic tendency to aggregate and lack of stability but also to realize an interacting surface suitable for biofunctionalization without strongly losing their magnetic response. Here, we describe an MR biosensor in which commercial MNP clusters were coated with gold nanoparticles (AuNPs) and used to detect human IgG in water using an MR biochip that comprises six sensing regions, each one containing five U-shaped spin valve sensors. The isolated AuNPs (satellites) were stuck onto an aggregate of individual iron oxide crystals (core) so that the resulting core@satellite magnetic particles (CSMPs) could be functionalized by the photochemical immobilization technique an easy procedure that leads to oriented antibodies immobilized upright onto gold. The morphological, optical, hydrodynamic, magnetic, and surface charge properties of CSMPs were compared with those exhibited by the commercial MNP clusters showing that the proposed coating procedure endows the MNP clusters with stability and ductility without being detrimental to magnetic properties. Eventually, the high-performance MR biosensor allowed us to detect human IgG in water with a detection limit of 13 pM (2 ng mL-1). Given its portability, the biosensor described in this paper lends itself to a point-of-care device; moreover, the features of the MR biochip also make it suitable for multiplexed analysis.

Copolymers of isotactic polypropylene (iPP) with 4-methyl-1-pentene (iPP4MP) were prepared with a highly isoselective homogeneous organometallic catalyst in a range of 4-methyl-1-pentene (4MP) concentrations between about 1.7 and 14 mol %. Crystallization from the melt at different crystallizations temperatures have been performed to study the effect of 4MP comonomeric units excluded from the crystals on the crystallization of α and γforms. All samples crystallize in mixtures of α and γforms, and for each sample, the fraction of γform increases with increasing crystallization temperature to achieve a maximum value fγ(max), which depends on the 4MP concentration. Compared to the homopolymer, the maximum fractional amount of γform fγ(max) rapidly increases with increasing 4MP content achieving the highest value of 92% at low 4MP concentration of 2.2 mol %, and decreases with a further increase of 4MP concentration. These data are compared with analogous data of the maximum amount of γform that develops in copolymers of iPP with ethylene and butene. This allows comparing the different effects of rejection of defects from the crystals, which produces interruption of the regular propene sequences and shortening of the length of the crystallizable sequences, the inclusion of defects into crystals of α and γforms, and the effect of the crystallization kinetics. Since 4MP comonomeric units are excluded from the crystals, the behavior of iPP4MP copolymers provides the sole interruption effect, which is highly efficient and produces the highest amount of γform of 92% at low 4MP concentration of nearly 2 mol %. The observed decrease of fγ(max) at higher 4MP concentrations is due to the too slow crystallization rate of the γform at these 4MP contents that induces the crystallization of the kinetically favored α form. In fact, crystals of γforms that develop in these copolymers are highly defective and show melting temperatures lower than those of the α form and, therefore, experience low undercooling at high crystallization temperatures. These results demonstrate that in metallocene iPP copolymers containing a significant amount of constitutional defects, the crystallization of the γform is favored because of the short regular propene sequences, whereas the crystallization of the α form is always kinetically favored.

The waste-to-wealth strategy is encouraging the design of a plethora of new value-added materials, by exploiting the chemical and biological richness of biowastes. Humic Acids (HA) are mostly intriguing because of their amphiphilic supramolecular associations which are responsible for several assets, such as adsorption ability towards small molecules, metal ion chelation, redox behavior, and antibacterial activity. The molecular combination of HA with semiconductor nanoparticles represents a valuable strategy to obtain nanostructured hybrid materials and interfaces with advanced features. Concurrently, it permits to overcome intrinsic limits of such organic fraction, including poor stability, fast conformational dynamics, or rapid reactivity in aqueous media. Herein, hybrid HA/ZnO nanoparticles are synthetized through a bottom-up strategy, exerting an improved pro-oxidant behavior by generating Reactive Oxygen Species, even without light irradiation, favoring an enhanced photocatalytic and antimicrobial activity against different bacterial pathogens. Several techniques, including SEM/TEM, DLS, ζ-potential, XRD, FTIR, TGA/DSC, EPR and DRUV, allows to define the structure-property-function relationships, thus highlighting the crucial role of a fine conjugation amongst the metal oxide precursor and bioderived fraction to drive the pro-oxidant activity. This study provides strategic guidelines to easily produce low-cost organo-inorganic nanomaterials with redox and biocide properties, aimed at coping environmental and health issues.

The crystallization behavior of propene–ethylene (iPPC2), propene–butene (iPPC4), propene–pentene (iPPC5), and propene–hexene (iPPC6) isotactic copolymers, prepared with single center metallocene catalysis, is described. Thanks to the perfectly random distribution of comonomers along the macromolecules, these copolymers can be considered as model for the crystallization behavior of isotactic polypropylene (iPP) that is mainly defined by the average length of the regular propene sequences. A model of the crystallization behavior of iPP is described based on the definition of a double effect of defects (stereodefects and comonomers), the interruption effect of defects excluded from the crystals that shortens the length of the crystallizable propene sequences inducing crystallization of the γ form, and the effect of inclusion of defects in the crystals of α form, γ form or δ form that induces the crystallization of the form whose lattice is less disturbed by the defect.

The biogenic synthesis of nanomaterials, i.e., synthesis carried out by means of living organisms, is an emerging technique in nanotechnology since it represents a greener and more eco-friendly method for the production of nanomaterials. In this line, in order to find new biological entities capable of biogenic synthesis, we tested the ability of some extremophilic microorganisms to carry out the biogenic production of AgNPs and SeNPs. Silver NPs were produced extracellularly by means of the thermophilic Thermus thermophilus strain SAMU; the haloalkaliphilic Halomonas campaniensis strain 5AG was instead found to be useful for the synthesis of SeNPs. The structural characterization of the biogenic nanoparticles showed that both the Ag and Se NPs possessed a protein coating on their surface and that they were organized in aggregates. Moreover, both types of NPs were found be able to exert an interesting antibacterial effect against either Gram-positive or Gram-negative species. This study confirmed that extremophilic microorganisms can be considered valuable producers of biologically active nanoparticles; nevertheless, further experiments must be performed to improve the synthesis protocols in addition to the downstream processes.

Objectives: To explore perinatal outcomes in SARS-CoV-2 vaccinated pregnant women comparing with unvaccinated counterparts. Methods: Search was conducted using Web of Science, Scopus, ClinicalTrial.gov, MEDLINE, Embase, OVID and Cochrane Library as electronic databases. We included observational studies evaluating pregnant women undergoing SARS-CoV-2 vaccination and compared pregnancy and perinatal outcomes with unvaccinated ones. Categorical variables were assessed using Odds Ratio (OR) with 95% Confidence Interval (CI), while for continuous variables results were expressed as Mean difference (MD) with their 95% Confidence Interval. All analyses were performed by adopting the random effect model of DerSimonian and Laird. Results: There is no difference in the probability of having a small for gestational age fetus (OR 0.97, 95% CI 0.85-1.09; p=0.570), while we observed a reduced probability of a non-reassuring fetal monitoring, a reduced gestational age at delivery and a reduced probability of premature delivery in vaccinated pregnant women versus unvaccinated ones. Conclusion: The probability of small for gestational age is similar between vaccinated and unvaccinated pregnant women, and the former had also a slightly reduced rate of premature delivery. Keywords: COVID-19; SARS-CoV-2; meta-analysis; pregnancy; preterm birth; small for gestational age; systematic review; vaccine.

Stimulated Raman scattering in transparent glass-ceramics (TGCs) based on bulk nucleating phase Ba2NaNb5O15 were investigated with the aim to explore the influence of micro- and nanoscale structural transformations on Raman gain. Nanostructured TGCs were synthesized, starting with 8BaO·15Na2O·27Nb2O5·50SiO2 (BaNaNS) glass, by proper nucleation and crystallization heat treatments. TGCs are composed of nanocrystals that are 10–15 nm in size, uniformly distributed in the residual glass matrix, with a crystallinity degree ranging from 30 up to 50% for samples subjected to different heat treatments. A significant Raman gain improvement for both BaNaNS glass and TGCs with respect to SiO2 glass is demonstrated, which can be clearly related to the nanostructuring process. These findings show that the nonlinear optical functionalities of TGC materials can be modulated by controlling the structural transformations at the nanoscale rather than microscale.

Chromium complexes bearing non-innocent iminopyridine ligands were investigated as precatalysts for the polymerization of ethylene using different aluminum cocatalysts and Lewis base NEt3 as additive. Beyond confirming the key role of the chromium to ligand synergy in accessing the active complex, other factors that play a crucial role are (i) the nature of the aluminum activator that influences the ion pair generated, (ii) the presence of the additive that boosts the synthesis of UHMWPE with narrow and unimodal molecular weight distribution even at 40 °C, and (iii) the polymerization temperature that affects the polymerization catalysis and the polymer molecular weight. UV-vis-NIR and Fourier transform infrared (FT-IR) spectroscopic techniques have been applied to inspect the activation process and to understand the mode of action by which NEt3 affects the catalytic conversion of ethylene. NEt3 interacts with the aluminum cocatalyst (rather than with the chromium complex) to form an Et3N-AlRx adduct, thus affecting the catalytic ion pair.

INTRODUCTION: Hormonal changes during pregnancy may induce modifications in oral mucosa. Epulis gravidarum (EG) is an oral disease arising during pregnancy, usually regressing after delivery. A case of EG managed at our department is described and those previously reported in literature are reviewed in order to define EG clinical features for stratifying the risk of complications and the need of surgery during pregnancy as well as which factors should be considered more relevant in EG management. EVIDENCE ACQUISITION: Electronic databases (Medline, Embase, Web of Sciences, Scopus and Cochrane Library) were searched from inception of each databases until May 2021 to identify clinical studies on management of EG diagnosed during pregnancy. The aim of this review was to identify factors influencing the need and timing of surgical management. EVIDENCE SYNTHESIS: A woman with a triplet pregnancy suffering from EG, complicated by profuse bleeding, required Caesarean section (CS) given the triplet pregnancy and the impending preterm labor. The surgical removal of EG was not performed because it spontaneously regressed without consequences 40 days after delivery. Review analysis indicated that EG clinical management is dependent on types of symptoms and their severity. Multilinear regression analysis showed that operative management strategy was associated with bone loss on X-ray (t=4.23, P=0.003), while EG surgical treatment during pregnancy was associated with pain (t=-2.91, P=0.03). No significant differences were found in management strategy, according to pain (P=0.12), interference with mastication (P=0.98) and speech (P=0.36). A poor oral hygiene was described in 71% of patients as hypothetical trigger. CONCLUSIONS: EG management strategy depends on bleeding, pain and bone loss on X-ray. A multidisciplinary approach is useful to perform a rapid and appropriate diagnosis and to better evaluate pros and cons of surgery during pregnancy and following management.

An example of breaking "Ewen's symmetry rule" for olefin catalysis polymerization is proposed by DFT calculations. Catalyst precursors with Cs symmetry are suggested to promote the isotactic propene polymerization by a modification of the active site geometry obtained via coordination with AlH-alkyl species in solution. The origin of stereocontrol in olefin polymerization is due to a dual mechanism dictated by the chiral catalyst. These findings may expand the toolbox for promoting stereoselective olefin polymerization by transition metal catalysts.

The crystallization behavior of butene-ethylene random isotactic copolymers prepared with a Ziegler-Natta catalyst, in particular the surprising crystallization of form II of isotactic polybutene in samples with a high ethylene concentration, provides novel evidence of the long-debated blocky molecular structure of these "random" copolymers.

Topical antimicrobial treatments are often ineffective on recalcitrant and resistant skin infections. This necessitates the design of antimicrobials that are less susceptible to resistance mechanisms, as well as the development of appropriate delivery systems. These two issues represent a great challenge for researchers in pharmaceutical and drug discovery fields. Here, we defined the therapeutic properties of a novel peptidomimetic inspired by an antimicrobial sequence encrypted in human apolipoprotein B. The peptidomimetic was found to exhibit antimicrobial and anti-biofilm properties at concentration values ranging from 2.5 to 20 µmol L−1, to be biocompatible toward human skin cell lines, and to protect human keratinocytes from bacterial infections being able to induce a reduction of bacterial units by two or even four orders of magnitude with respect to untreated samples. Based on these promising results, a hyaluronic-acid-based hydrogel was devised to encapsulate and to specifically deliver the selected antimicrobial agent to the site of infection. The developed hydrogel-based system represents a promising, effective therapeutic option by combining the mechanical properties of the hyaluronic acid polymer with the anti-infective activity of the antimicrobial peptidomimetic, thus opening novel perspectives in the treatment of skin infections.

Encrypted peptides have been recently found in the human proteome and represent a potential class of antibiotics. Here we report three peptides derived from the human apolipoprotein B (residues 887-922) that exhibited potent antimicrobial activity against drug-resistant Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococci both in vitro and in an animal model. The peptides had excellent cytotoxicity profiles, targeted bacteria by depolarizing and permeabilizing their cytoplasmic membrane, inhibited biofilms, and displayed anti-inflammatory properties. Importantly, the peptides, when used in combination, potentiated the activity of conventional antibiotics against bacteria and did not select for bacterial resistance. To ensure translatability of these molecules, a protease resistant retro-inverso variant of the lead encrypted peptide was synthesized and demonstrated anti-infective activity in a preclinical mouse model. Our results provide a link between human plasma and innate immunity and point to the blood as a source of much-needed antimicrobials.