Arbuscular Mycorrhizal Symbiosis Limits Foliar Transcriptional Responses to Viral Infection and Favors Long-Term Virus Accumulation

Tomato (Solanum lycopersicum) can establish symbiotic interactions with arbuscular mycorrhizal (AM) fungi, and can be infected by several pathogenic viruses. Here, we investigated the impact of mycorrhization by the fungus Glomus mosseae on the Tomato spotted wilt virus (TSWV) infection of tomato plants by transcriptomic and hormones level analyses. In TSWV-infected mycorrhizal plants, the AM fungus root colonization limited virus-induced changes in gene expression in the aerial parts. The virus-responsive upregulated genes, no longer induced in infected mycorrhizal plants, were mainly involved in defense responses and hormone signaling, while the virus-responsive downregulated genes, no longer repressed in mycorrhizal plants, were involved in primary metabolism. The presence of the AM fungus limits, in a salicylic acid-independent manner, the accumulation of abscissic acid observed in response to viral infection. At the time of the molecular analysis, no differences in virus concentration or symptom severity were detected between mycorrhizal and nonmycorrhizal plants. However, in a longer period, increase in virus titer and delay in the appearance of recovery were observed in mycorrhizal plants, thus indicating that the plant's reaction to TSWV infection is attenuated by mycorrhization. </jats:p

LOW-LYING ZEROS IN FAMILIES OF HOLOMORPHIC CUSP FORMS: THE WEIGHT ASPECT

We study low-lying zeros of L-functions attached to holomorphic cusp forms of level 1 and large even weight. In this family, the Katz-Sarnak heuristic with orthogonal symmetry type was established in the work of Iwaniec, Luo and Sarnak for test functions phi satisfying the condition supp((phi) over cap) subset of (-2, 2). We refine their density result by uncovering lower-order terms that exhibit a sharp transition when the support of (phi) over cap reaches the point 1. In particular, the first of these terms involves the quantity (phi) over cap (1) which appeared in the previous work of Fouvry-Iwaniec and Rudnick in symplectic families. Our approach involves a careful analysis of the Petersson formula and circumvents the assumption of the Generalized Riemann Hypothesis (GRH) for higher-degree automorphic L-functions. Finally, when supp((phi) over cap) subset of (-1, 1) we obtain an unconditional estimate which is significantly more precise than the prediction of the L-functions ratios conjecture

3d printing in alginic acid bath of in-situ crosslinked collagen composite scaffolds

Bone-tissue regeneration is a growing field, where nanostructured-bioactive materials are designed to replicate the natural properties of the target tissue, and then are processed with technolo-gies such as 3D printing, into constructs that mimic its natural architecture. Type I bovine collagen formulations, containing functional nanoparticles (enriched with therapeutic ions or biomolecules) or nanohydroxyapatite, are considered highly promising, and can be printed using support baths. These baths ensure an accurate deposition of the material, nonetheless their full removal post-printing can be difficult, in addition to undesired reactions with the crosslinking agents often used to improve the final structural integrity of the scaffolds. Such issues lead to partial collapse of the printed constructs and loss of geometrical definition. To overcome these limitations, this work presents a new alternative approach, which consists of adding a suitable concentration of crosslinking agent to the printing formulations to promote the in-situ crosslinking of the constructs prior to the removal of the support bath. To this aim, genipin, chosen as crosslinking agent, was added (0.1 wt.%) to collagen-based biomaterial inks (containing either 38 wt.% mesoporous bioactive glasses or 65 wt.% nanohydroxyapatite), to trigger the crosslinking of collagen and improve the stability of the 3D printed scaffolds in the post-processing step. Moreover, to support the material deposition, a 15 wt.% alginic acid solution was used as a bath, which proved to sustain the printed structures and was also easily removable, allowing for the stable processing of high-resolution geometries

PEG-coated large mesoporous silicas as smart platform for protein delivery and their use in a collagen-based formulation for 3d printing

Silica-based mesoporous systems have gained great interest in drug delivery applications due to their excellent biocompatibility and high loading capability. However, these materials face challenges in terms of pore-size limitations since they are characterized by nanopores ranging between 6–8 nm and thus unsuitable to host large molecular weight molecules such as proteins, enzymes and growth factors (GFs). In this work, for an application in the field of bone regeneration, large-pore mesoporous silicas (LPMSs) were developed to vehicle large biomolecules and release them under a pH stimulus. Considering bone remodeling, the proposed pH-triggered mechanism aims to mimic the release of GFs encased in the bone matrix due to bone resorption by osteoclasts (OCs) and the associated pH drop. To this aim, LPMSs were prepared by using 1,3,5-trimethyl benzene (TMB) as a swelling agent and the synthesis solution was hydrothermally treated and the influence of different process temperatures and durations on the resulting mesostructure was investigated. The synthesized particles exhibited a cage-like mesoporous structure with accessible pores of diameter up to 23 nm. LPMSs produced at 140◦C for 24 h showed the best compromise in terms of specific surface area, pores size and shape and hence, were selected for further experiments. Horseradish peroxidase (HRP) was used as model protein to evaluate the ability of the LPMSs to adsorb and release large biomolecules. After HRP-loading, LPMSs were coated with a pH-responsive polymer, poly(ethylene glycol) (PEG), allowing the release of the incorporated biomolecules in response to a pH decrease, in an attempt to mimic GFs release in bone under the acidic pH generated by the resorption activity of OCs. The reported results proved that PEG-coated carriers released HRP more quickly in an acidic environment, due to the protonation of PEG at low pH that catalyzes polymer hydrolysis reaction. Our findings indicate that LPMSs could be used as carriers to deliver large biomolecules and prove the effectiveness of PEG as pH-responsive coating. Finally, as proof of concept, a collagen-based suspension was obtained by incorporating PEG-coated LPMS carriers into a type I collagen matrix with the aim of designing a hybrid formulation for 3D-printing of bone scaffolds

A Low Rhodium Content Smart Catalyst for Hydrogenation and Hydroformylation Reactions

Abstract: This paper describes the preparation, broad characterization and study of activity in hydrogenation and hydroformylation reactions of an easily produced 0.18% Rh/Al2O3. Analytical studies on fresh and recycled samples shed light on the smart properties of such catalyst. Results showed high activity as well as fine/excellent chemoselectivity or regioselectivity, characteristics that may suggest a wide range of applicability. Graphic Abstract: The low metal content catalyst 0.18% Rh/Al2O3 was very active in both hydrogenation and hydroformylation reactions so providing intermediates for valuable APIs, as Nabumetone and Eletriptan, and a fragrance with a fresh, green-floral smell, that recalls scent of lily of the valley.[Figure not available: see fulltext.

Electrophoretic deposition of Sr-containing mesoporous bioactive glass particles produced by spray-drying

Introduction Mesoporous bioactive glasses (MBGs) are gaining increasing interest in the biomedical field thanks to their exceptional textural characteristics (high surface area, high pore volume and highly ordered mesoporosity). These properties lead to an improved apatite kinetics formation, which allow these glasses to be successfully applied in bone tissue regeneration [1]. In this work we adopted an aerosol-based spray drying process in order to have high control and reproducibility over the morphology of particles. In order to increase their regenerative potential, the particles have been doped with strontium, element known for its osteogenic and bone antiresorptive properties [2]. Later the particles have been deposed by electrophoretic deposition (EPD) on glass-ceramic scaffolds fabricated by the polymer sponge replication method. EPD is a versatile technique which allows an easy control of the thickness of the deposited film through simple adjustment of the applied voltage and the deposition time. The scaffolds, based on a quaternary silicate glass (SCNA, SiO2–CaO–Na2O–Al2O3 oxide system), have good mechanical properties but low bioactivity [3]. Thanks to MBG particle deposition, they acquire a pronounced bioactive behaviour, thus becoming an excellent solution for bone tissue regeneration. Results and Discussion MBGs synthesized with the aerosol-based spray-drying process have a basic composition on the SiO2-CaO system and have been doped with the 1% molar of strontium (SD_Sr1). FESEM image of particles shows micro-sized spherical particles, with size mostly ranging between 500 nm and 5 µm. N2 adsorption analysis gives back a high specific surface area value, 160 m2/g, and a pore size distribution between 5 and 9 nm, which confirms the mesoporosity of the sample. Strontium incorporation inside the binary composition does not modify the bioactive behaviour of the glass: after 14 days in SBF nanoparticles are completely covered by a layer of hydroxyapatite.The EDS quantitative analysis shows that the amount of strontium effectively incorporated in the microparticles was 70% of the theoretical one, probably because of the high dimension of the ion which hinders its entrance into the glass network. Nevertheless, most of the Sr incorporated has been released after 14 days of immersion in SBF, as the coupled plasma-atomic emission spectrometry (ICP-AES) reveals. On the basis of literature data, the released concentrations are suitable for inducing osteogenesis [4]. EPD has been performed in ethanol, applying a voltage of 120 V for 5 minutes. The scaffolds, being not conductive, have been suspended between two stainless steel electrodes through a clamp. A dispersant (TEA, triethanolamine) has been used to keep the particles in suspension during the whole deposition time. The deposited layer was abundant but not uniform on the scaffold surface. After immersion for 7 days in SBF, hydroxyapatite formation has been observed on the surface of the microparticles deposited on the scaffold struts. This demonstrates that MBGs not only maintain their bioactivity after deposition but also transfer this property to scaffolds. Conclusions MBGs synthetized with aerosol-based spray-drying process and doped with strontium have excellent textural properties and a bioactive behaviour. After electrophoretic deposition, they maintain these properties and consequently they improve the bioactivity of SCNA scaffolds, which initially are almost biologically inert. In this way we demonstrate that it is possible to obtain a successful construct for bone tissue engineering with both excellent regenerative and mechanical properties

Long-term impact of chemical and alternative fungicides applied to grapevine CV nebbiolo on berry transcriptome

Viticulture is one of the horticultural systems in which antifungal treatments can be extremely frequent, with substantial economic and environmental costs. New products, such as biofungicides, resistance inducers and biostimulants, may represent alternative crop protection strategies respectful of the environmental sustainability and food safety. Here, the main purpose was to evaluate the systemic molecular modifications induced by biocontrol products as laminarin, resistance inducers (i.e., fosetyl-Al and potassium phosphonate), electrolyzed water and a standard chemical fungicide (i.e., metiram), on the transcriptomic profile of ‘Nebbiolo’ grape berries at harvest. In addition to a validation of the sequencing data through real-time polymerase chain reaction (PCR), for the first-time the expression of some candidate genes in different cell-types of berry skin (i.e., epidermal and hypodermal layers) was evaluated using the laser microdissection approach. Results showed that several considered antifungal treatments do not strongly affect the berry transcriptome profile at the end of season. Although some treatments do not activate long lasting molecular defense priming features in berry, some compounds appear to be more active in long-term responses. In addition, genes differentially expressed in the two-cell type populations forming the berry skin were found, suggesting a different function for the two-cell type populations

Hydrothermally-assisted recovery of Yttria- stabilized zirconia (YSZ) from end-of-life solid oxide cells

Effective and scalable recycling strategies for the recovery of critical raw materials are yet to be validated for solid oxide cells (SOCs) technologies. The current study aimed at filling this gap by developing optimized recycling processes for the recovery of Yttria-stabilized Zirconia (YSZ) from End-of-Life (EoL) SOC components, in view of using the recovered ceramic phase in cell re-manufacturing. A multi-step procedure, including milling, hydrothermal treatment (HT), and acidic-assisted leaching of nickel from composite Ni-YSZ materials, has been implemented to obtain recovered YSZ powders with defined specifications, in terms of particle size distribution, specific surface area, and chemical purity. The overall optimized procedure includes a pre-milling step (6 h) of the EoL composite materials, and a hydrothermal (HT) treatment at 200 °C for 4 h to further disaggregate the sintered composite, followed by selective oxidative leaching of Ni2+ by HNO3 solution at 80 °C for 2 h. In particular, the intermediate HT step was assessed to play an essential role in promoting the disaggregation of the sintered powders, with a related increase of specific surface area (up to 13 m2 g−1) and the overall reduction of the primary particle aggregates. The acid-assisted leaching allowed to fully extract Nickel from the composite Ni-YSZ powders, with retention of YSZ crystallinity and negligible loss of Zr and Y, as revealed by ICP analysis on the recovered supernatants. The developed multi-step pathway offers a promising strategy to recover valuable YSZ materials for the re-manufacturing of SOCs components, with the aim to boost a circular economy approach in the field of fuel-cell and hydrogen (FCH) technologies

Achievements in Mesoporous Bioactive Glasses for Biomedical Applications

Nowadays, mesoporous bioactive glasses (MBGs) are envisaged as promising candidates in the field of bioceramics for bone tissue regeneration. This is ascribed to their singular chemical composition, structural and textural properties and easy-to-functionalize surface, giving rise to accelerated bioactive responses and capacity for local drug delivery. Since their discovery at the beginning of the 21st century, pioneering research efforts focused on the design and fabrication of MBGs with optimal compositional, textural and structural properties to elicit superior bioactive behavior. The current trends conceive MBGs as multitherapy systems for the treatment of bone-related pathologies, emphasizing the need of fine-tuning surface functionalization. Herein, we focus on the recent developments in MBGs for biomedical applications. First, the role of MBGs in the design and fabrication of three-dimensional scaffolds that fulfil the highly demanding requirements for bone tissue engineering is outlined. The different approaches for developing multifunctional MBGs are overviewed, including the incorporation of therapeutic ions in the glass composition and the surface functionalization with zwitterionic moieties to prevent bacterial adhesion. The bourgeoning scientific literature on MBGs as local delivery systems of diverse therapeutic cargoes (osteogenic/antiosteoporotic, angiogenic, antibacterial, anti-inflammatory and antitumor agents) is addressed. Finally, the current challenges and future directions for the clinical translation of MBGs are discussed