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We report calculations of the phase diagram and spinodal decomposition line of a charged hard-sphere fluid mixture constituted of two different cations, one anion and one neutral particle species. In the high-density regime the model is suitable to mimic molten silicate and metal halides mixtures, as those forming a magmatic fluid; in the low-density regime it can conveniently describe the properties of charged colloidal suspensions or micellar solutions. In this work the attention is focused mainly on the high-density regime of the mixture, and phase stability conditions are determined through the knowledge of the Gibbs free energy of mixing, Gmix at constant pressure, as calculated in the mean spherical approximation. It turns out that the solubility of the neutral component in the ionic mixture depends substantially on the potential-to-kinetic-energy ratio, that is, on the so-called coupling strength or plasma parameter, and increases when this decreases. This result is rationalized by considering the different terms contributing to Gmix and, specifically, the confi-gurational Coulombic internal energy term and entropic term. The fine balance between these two quantities is detailed and the onset of phase segregation discussed on these same bases. Such a representation also allows us to interpret why mixtures like those envisaged here are characterized by a phase diagram with an upper consolution point and why the critical temperature turns out to be an increasing function of the pressure. The implications of this last result seem interesting since, e.g., molten salt-silicate mixtures and, therefore, presumably fused rocks or magmas, could segregate not only under cooling, but also at constant temperature as the result of pressure variations. [ABSTRACT FROM AUTHOR]

The southern king crab (SKC) Lithodes santolla is a crustacean parasitised by the bopyrid Eremitione tuberculata. This study aimed to analyse spatial and temporal variations in E. tuberculata prevalence in the juvenile SKC population of San Jorge Gulf (SJG) and adjacent waters (Argentine Patagonia), and evaluate the effects of the parasite on SKC juveniles to improve our understanding of its impact as a disease on SKC health condition. Moult increment and body weight were compared between parasitised and unparasitised individuals. The prevalence of E. tuberculata in SKC juveniles varied both spatially and temporally. In the south of SJG, the prevalence was 54.5% (n = 11). Temporal prevalence analysis revealed values lower than 17.4% in mid SJG during May and September 2015. No significant differences were observed in E. tuberculata prevalence between sexes or among seasons. Eremitione tuberculata had a negative effect on SKC growth (lower body dry mass, moult increment and relative increment rate) in parasitised individuals. We hypothesised that the higher prevalence of E. tuberculata in the south SJG could be attributed to the retention of parasite larvae and the presence of the frontal system in this part of the gulf. The temporal variations could reflect host mortality. Our results suggest that bopyrid infestation may have a more important role than previously believed in the dynamics of the SKC population in mid-Patagonia.

During AD pathology, Tau protein levels progressively increase from early pathological stages. Tau altered expression causes an unbalance of Tau subcellular localization in the cytosol and in the nuclear compartment leading to synaptic dysfunction, neuronal cell death and neurodegeneration as a consequence. Due to the relevant role of epigenetic remodellers in synaptic activity in physiology and in neurodegeneration, in particular of TRIM28 and HDAC1, we investigated the relationship between Tau and these epigenetic factors. By molecular, imaging and biochemical approaches, here we demonstrate that Tau altered expression in the neuronal cell line SH-SY5y does not alter TRIM28 and HDAC1 expression but it induces a subcellular reduction of HDAC1 in the nuclear compartment. Remarkably, HDAC1 reduced activity modulates the expression of synaptic genes in a way comparable to that observed by Tau increased levels. These results support a competitive relationship between Tau levels and HDAC1 subcellular localization and nuclear activity, indicating a possible mechanism mediating the alternative role of Tau in the pathological alteration of synaptic genes expression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Siano, Madaro, Caiazza, Allouch, Varisco, Mignanelli, Cattaneo and Di Primio.)

The crystal structure of [Co 2 Cl 4 (C 17 H 18 N 2 ) 2 ][CoCl 2 (C 17 H 18 N 2 )(H 2 O)] or [Co( L )Cl(μ-Cl)] 2 [Co( L )(Cl) 2 (OH 2 )], where L is the enanti-opure bidentate ligand (-)-5,6-pinenebi-pyridine (C 17 H 18 N 2 ), has been determined. Crystals suitable for X-ray structure analysis were obtained by slow evaporation of an ethano-lic solution containing equimolar amounts of L and CoCl 2 ·6H 2 O. The Co II cations all have a coordination number of five, and in each case the coordination polyhedron is a trigonal bipyramid. The Co-N bonds lengths range from 2.037 (7) to 2.195 (7) Å, and Co-Cl bonds lengths range from 2.284 (2) to 2.509 (2) Å. The asymmetric unit contains two discrete complexes, one dinuclear and the other mononuclear. Between the two mol-ecules, two types of inter-molecular inter-actions have been evidenced: π-π stackings involving the bi-pyridine units, and O-H⋯Cl hydrogen bonds between the hydrogen atoms of the aqua ligand coordinating to the mononuclear complex and the non-bridging chlorido ligand coordinating to the dinuclear mol-ecule. These inter-actions lead to a two-dimensional supra-molecular arrangement parallel to the ab plane., (© Varisco et al. 2022.)

Two experimental methods, the Nile Red dye extraction and the Williamson ether synthesis in biphasic conditions, were used to characterize the mixing performance of a new cheap impinging jet colliding mixer from Gjosa and to compare it to other commercial micromixers (Caterpillar CPMM-R300, T-mixer, LTF MR-MX and LTF MR-MS). The Nile Red method shows that the Caterpillar mixer is the best one. Excellent results are also achieved with two Gjosa mixers in series. These results are not reflected in the Williamson ether synthesis, where the best mixer is the Gjosa one.

Aim and Objective: The purpose of this work is to investigate by electromyographic (EMG) surface analysis whether and how the variations in the occlusion due to the correction of the posterior crossbite using a rapid palatal expander (RPE) is accompanied by changes in the activity of the elevator muscles in the pediatric patients., Background: Posterior crossbite is a disgnathic jaw relationship common in patients undergoing growth. In the last 10 years, several studies demonstrated the effectiveness and reproducibility of surface EMG in the objective evaluation of temporal muscle and masseter activity and how this evidence can be an interesting aid in dental clinical practice., Case Description: The case subject BF is an 11-year-old boy with a right I class relationship and a left II class relationship treated with a rapid palatal expansion protocol with a turn of the transversal screw twice a day (0.25 mm each turn) for a week. In this case report, EMG was used to evaluate the temporal muscle and masseter activity immediately before, immediately after, and 4 months after the RPE protocol., Conclusion: Four months after the treatment, a condition of well-being and neuromuscular equilibrium such as that of starting was preserved., Clinical Significance: Electromyography is a noninvasive exam which evaluates the masticatory muscle activity by facial application of electrodes on masseter and temporal muscles. It can be an interesting aid in orthodontic clinical practice to evaluate preservation of a good muscular balance following orthodontic and orthognathic movements.

Tau is a microtubule binding protein expressed in neurons and its main known function is related to the maintenance of cytoskeletal stability. However, recent evidence indicated that Tau is present also in other subcellular compartments including the nucleus where it is implicated in DNA protection, in rRNA transcription, in the mobility of retrotransposons and in the structural organization of the nucleolus. We have recently demonstrated that nuclear Tau is involved in the expression of the VGluT1 gene, suggesting a molecular mechanism that could explain the pathological increase of glutamate release in the early stages of Alzheimer's disease. Until recently, the involvement of nuclear Tau in modulating the expression of target genes has been relatively uncertain and ambiguous due to technical limitations that prevented the exclusion of the contribution of cytoplasmic Tau or the effect of other downstream factors not related to nuclear Tau. To overcome this uncertainty, we developed a method to study the expression of target genes specifically modulated by the nuclear Tau protein. We employed a protocol that couples the use of localization signals and the subcellular fractionation, allowing the exclusion of the interference from the cytoplasmic Tau molecules. Most notably, the protocol is easy and is composed of classic and reliable methods that are broadly applicable to study the nuclear function of Tau in other cell types and cellular conditions.

Formation of Tau aggregates is a common pathological feature of tauopathies and their accumulation directly correlates with cytotoxicity and neuronal degeneration. Great efforts have been made to understand Tau aggregation and to find therapeutics halting or reversing the process, however, progress has been slowed due to the lack of a suitable method for monitoring Tau aggregation. We developed a cell-based assay allowing to detect and quantify Tau aggregation in living cells. The system is based on the FRET biosensor CST able to monitor the molecular dynamic of Tau aggregation in different cellular conditions. We probed candidate compounds that could block Tau hyperphosphorylation. In particular, to foster the drug discovery process, we tested kinase inhibitors approved for the treatment of other diseases. We identified the ERK inhibitor PD-901 as a promising therapeutic molecule since it reduces and prevents Tau aggregation. This evidence establishes the CST cell-based aggregation assay as a reliable tool for drug discovery and suggests that PD-901 might be a promising compound to be tested for further preclinical studies on AD.

Tau displacement from microtubules is the first step in the onset of tauopathies and is followed by toxic protein aggregation. However, other non-canonical functions of Tau might have a role in these pathologies. Here, we demonstrate that a small amount of Tau localizes in the nuclear compartment and accumulates in both the soluble and chromatin-bound fractions. We show that favoring Tau nuclear translocation and accumulation, by Tau overexpression or detachment from MTs, increases the expression of VGluT1, a disease-relevant gene directly involved in glutamatergic synaptic transmission. Remarkably, the P301L mutation, related to frontotemporal dementia FTDP-17, impairs this mechanism leading to a loss of function. Altogether, our results provide the demonstration of a direct physiological role of Tau on gene expression. Alterations of this mechanism may be at the basis of the onset of neurodegeneration., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Wine lees are one of the main residues formed in vast quantities during the fermentation of wine. While toxic when applied to plants and wetlands, it is a biodegradable material, and several alternatives have been proposed for its valorization as: dietary supplement in animal feed, source for various yeast extracts and bioconversion feedstock. The implementation of stricter environment protection regulations resulted in increasing costs for wineries as their treatment process constitutes an unavoidable and expensive step in wine production. We propose here an alternative method to reduce waste and add value to wine production by exploiting this rich carbon source and use it as a raw material for producing carbon quantum dots (CQDs). A complete synthetic pathway is discussed, comprising the carbonization of the starting material, the screening of the most suitable solvent for the extraction of CQDs from the carbonized mass and their hydrophobic or hydrophilic functionalization. CQDs synthesized with the reported procedure show a bright blue emission ( λ max  = 433 ± 13 nm) when irradiated at 366 nm, which is strongly shifted when the wavelength is increased (e.g. emission at around 515 nm when excited at 460 nm). Yields and luminescent properties of CQDs, obtained with two different methods, namely microwave and ultrasound-based extraction, are discussed and compared. This study shows how easy a residue can be converted into an added-value material, thus not only reducing waste and saving costs for the wine-manufacturing industry but also providing a reliable, affordable and sustainable source for valuable materials., Competing Interests: The authors declare no competing interests.

Carbon nanodots can be obtained in good yields by direct combustion of an abundant waste from the wine industry, wine lees. The extraction of these nanoparticles followed by their chemical functionalization lead to an ink-jettable material emitting in the visible region (blue) under specific UV irradiation.

The first heptacoordinate cobalt catalyst for light-driven hydrogen production in water has been synthesized and characterized. Photochemical experiments using [Ru(bpy) 3 ] 2+ as photosensitizer gave a turnover number (TON) of 16300 mol H 2  (mol cat.) -1 achieved in 2 hours of irradiation with visible (475 nm) light. This promising result provides a path forward in the development of new structures to improve the efficiency of the catalysis., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Implant-associated infections (IAIs) are a dreaded complication mainly caused by biofilm-forming staphylococci. Implant surfaces preventing microbial colonization would be desirable. We examined the preventive effect of a silver-coated titanium-aluminum-niobium (TiAlNb) alloy. The surface elicited a strong, inoculum-dependent activity againstStaphylococcus epidermidisandStaphylococcus aureusin an agar inhibition assay. Gamma sterilization and alcohol disinfection did not alter the effect. In a tissue cage mouse model, silver coating of TiAlNb cages prevented perioperative infections in an inoculum-dependent manner and led to a 100% prevention rate after challenge with 2 × 10(6)CFU ofS. epidermidisper cage. InS. aureusinfections, silver coating had only limited effect. Similarly, daptomycin or vancomycin prophylaxis alone did not preventS. aureusinfections. However, silver coating combined with daptomycin or vancomycin prophylaxis thwarted methicillin-resistantS. aureusinfections at a prevention rate of 100% or 33%, respectively. Moreover, silver release from the surface was independent of infection and occurred rapidly after implantation. On day 2, a peak of 82 μg Ag/ml was reached in the cage fluid, corresponding to almost 6× the MIC of the staphylococci. Cytotoxicity toward leukocytes in the cage was low and temporary. Surrounding tissue did not reveal histological signs of silver toxicity.In vitro, no emergence of silver resistance was observed in several clinical strains of staphylococci upon serial subinhibitory silver exposures. In conclusion, our data demonstrate that silver-coated TiAlNb is potent for prevention of IAIs and thus can be considered for clinical application., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Materials foreign to the body are used ever more frequently, as increasing numbers of patients require implants. As a consequence, the numbers of implant-related infections have grown as well, and with increasing resistance. Treatments often fail; thus, new antibacterial coating strategies are being developed by scientists to avoid, or at least strongly reduce, bacterial adhesion to implant surfaces. In this study, we focused on producing a self-protective coating combining silver(I) ions and a vancomycin-derived molecule, intelligent pyridinate vancomycin (IPV), with a synergetic and effective action against bacteria. These Ag(I) -IPV conjugate-coated surfaces are well characterized and exhibit strong bactericidal activity in vitro against Staphylococci strains. Furthermore, the released quantities of both drugs from the coated surfaces do not affect their biocompatibility and soft tissue integration. These newly developed Ag(I) -IPV conjugate coatings thus represent a possible and efficient protection method against bacterial adhesion and biofilm formation during and after implant surgery., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Posterior fossa surgery traditionally implies permanent bone removal. Although suboccipital craniectomy offers an excellent exposure, it could lead to complications. Thus, some authors proposed craniotomy as a valuable alternative to craniectomy. In the present study we compare postoperative complications after craniotomy or craniectomy for posterior fossa surgery., Methods: We prospectively collected data for a consecutive series of patients who underwent either posterior fossa craniotomy or craniectomy for tumor resection. We divided patients into two groups based on the surgical procedure performed and safety, complication rates and length of hospitalization were analyzed. Craniotomies were performed with Control-Depth-Attachment(®) drill and chisel, while we did craniectomies with perforator and rongeurs., Results: One-hundred-fifty-two patients were included in the study (craniotomy n =100, craniectomy n =52). We detected no dural damage after bone removal in both groups. The total complication rate related to the technique itself was 7 % for the craniotomy group and 32.6 % for the craniectomy group (<0.0001). Pseudomeningocele occurred in 4 % vs. 19.2 % (p =0.0009), CSF leak in 2 % vs. 11.5 % (p =0.006) and wound infection in 1 % vs. 1.9 % (p =0.33), respectively. Post-operative hydrocephalus, a multi-factorial complication which could affect our results, was also calculated and occurred in 4 % of the craniotomy vs. 9.6 % of the craniectomy group (p =0.08). The mean length of in-hospital stay was 9.3 days for the craniotomy group and 11.8 days for the craniectomy group (p =0.10)., Conclusions: The present study suggests that fashioning a suboccipital craniotomy is as effective and safe as performing a craniectomy; both procedures showed similar results in preserving dural integrity, while post-operative complications were fewer when a suboccipital craniotomy was performed.