The Role of P-Selectin in COVID-19 Coagulopathy: An Updated Review

In severe COVID-19, which is characterized by blood clots and neutrophil-platelet aggregates in the circulating blood and different tissues, an increased incidence of cardiovascular complications and venous thrombotic events has been reported. The inflammatory storm that characterizes severe infections may act as a driver capable of profoundly disrupting the complex interplay between platelets, endothelium, and leukocytes, thus contributing to the definition of COVID-19-associated coagulopathy. In this frame, P-selectin represents a key molecule expressed on endothelial cells and on activated platelets, and contributes to endothelial activation, leucocyte recruitment, rolling, and tissue migration. Briefly, we describe the current state of knowledge about P-selectin involvement in COVID-19 pathogenesis, its possible use as a severity marker and as a target for host-directed therapeutic intervention.     

Peptides from water buffalo cheese whey induced senescence cell death via ceramide secretion in human colon adenocarcinoma cell line

Scope: Milk proteins are a source of bioactive peptides. Recent studies have indicated that protein‐derived peptides released in buffalo cheese acid whey exert a cytomodulatory effect in human epithelial colon cancer (CaCo2) cells. The aim of the present study was to explain the molecular mechanism involved in the response of CaCo2 cells to oxidative stress in the presence of peptide fractions of buffalo cheese whey, purified and characterized by mass spectrometry. Methods and results: We demonstrated that treatment of CaCo2 treated with H₂O₂ (H‐CaCo2) cells with a partially purified peptide sub‐fraction (f3) from buffalo cheese acid whey induced a reduction of mitochondrial superoxide anion with subsequent decrease in heat shock protein 70 and 90 expression. Moreover, we observed a 5‐fold decrease in cyclin A expression and cell cycle arrest in G1/G0 phases. These responses were associated with increased activity of alkaline phosphatase and beta‐galactosidase, markers of differentiation and senescence respectively. Conclusions: The structural characterization of the active peptide fraction and the elucidation of the effects induced by its treatment on H‐CaCo2 cells in vitro demonstrated an activity of this peptide sub‐fraction in the modulation of cell cycle, thus suggesting potential application for the development of nutraceuticals as well as health‐promoting functional foods.     

Toward a better understanding of multifunctional cement-based materials: The impact of graphite nanoplatelets (GNPs)

The impact of graphite nanoplatelets (GNPs) on the physical and mechanical properties of cementitious nanocomposites was investigated. A market-available premixed mortar was modified with 0.01% by weight of cement of commercial GNPs characterized by two distinctively different aspect ratios.The rheological behavior of the GNP-modified fresh admixtures was thoroughly evaluated. Hardened cementitious nanocomposites were investigated in terms of density, microstructure (Scanning Electron Microscopy, SEM and micro–Computed Tomography, μ-CT), mechanical properties (three-point bending and compression tests), and physical properties (electrochemical impedance spectroscopy, EIS and thermal conductivity measurements). At 28 days, all GNP-modified mortars showed about 12% increased density. Mortars reinforced with high aspect ratio GNPs exhibited the highest compressive and flexural strength: about 14% and 4% improvements compared to control sample, respectively. Conversely, low aspect ratio GNPs led to cementitious nanocomposites characterized by 36% decreased electrical resistivity combined with 60% increased thermal conductivity with respect to the control sample.     

Theoretical and experimental studies of a new aniline derivative corrosion inhibitor for mild steel in acid medium

4-Chloro-N-(pyridin-2-ylmethyl)aniline (CPYA) was synthesized by a simple and inexpensive method and tested as a corrosion inhibitor in acid medium for mild steel by using gravimetric studies and electrochemical measurements. An average maximum efficiency of 96.0% was achieved at 4.59 mmol/L. Corrosion kinetic and thermodynamic parameters were also analyzed. Surface analyses (atomic force microscopy and scanning electron microscopy) show that protection is enabled by adsorption on the metal, forming a film. Quantum chemical calculations were performed to access information regarding the molecular structure in the corrosive medium and to support interpretation of the results obtained by experimental methods.     

Effects of Eltrombopag on In Vitro Macrophage Polarization in Pediatric Immune Thrombocytopenia

Immune Thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibodies-mediated platelet destruction, a prevalence of M1 pro-inflammatory macrophage phenotype and an elevated T helper 1 and T helper 2 lymphocytes (Th1/Th2) ratio, resulting in impairment of inflammatory profile and immune response. Macrophages are immune cells, present as pro-inflammatory classically activated macrophages (M1) or as anti-inflammatory alternatively activated macrophages (M2). They have a key role in ITP, acting both as effector cells, phagocytizing platelets, and, as antigen presenting cells, stimulating auto-antibodies against platelets production. Eltrombopag (ELT) is a thrombopoietin receptor agonist licensed for chronic ITP to stimulate platelet production. Moreover, it improves T and B regulatory cells functions, suppresses T-cells activity, and inhibits monocytes activation. We analyzed the effect of ELT on macrophage phenotype polarization, proposing a new possible mechanism of action. We suggest it as a mediator of macrophage phenotype switch from the M1 pro-inflammatory type to the M2 anti-inflammatory one in paediatric patients with ITP, in order to reduce inflammatory state and restore the immune system function. Our results provide new insights into the therapy and the management of ITP, suggesting ELT also as immune-modulating drug.     

Scytodecamide from the Cultured Scytonema sp. UIC 10036 Expands the Chemical and Genetic Diversity of Cyanobactins

Cyanobactins are a large family of cyanobacterial ribosomally synthesized and post-translationally modified peptides (RiPPs) often associated with biological activities, such as cytotoxicity, antiviral, and antimalarial activities. They are traditionally described as cyclic molecules containing heterocyclized amino acids. However, this definition has been recently challenged by the discovery of short, linear cyanobactins containing three to five amino acids as well as cyanobactins containing no heterocyclized residues. Herein we report the discovery of scytodecamide ( 1 ) from the freshwater cyanobacterium Scytonema sp. UIC 10036. Structural elucidation based on mass spectrometry, 1D and 2D NMR spectroscopy, and Marfey's method revealed 1 to be a linear decapeptide with an N-terminal N-methylation and a C-terminal amidation. The genome of Scytonema sp. UIC 10036 was sequenced, and bioinformatic analysis revealed a cyanobactin-like biosynthetic gene cluster consistent with the structure of 1 . The discovery of 1 as a novel linear peptide containing an N-terminal N-methylation and a C-terminal amidation expands the chemical and genetic diversity of the cyanobactin family of compounds.     

Grape stalk fibers as reinforcing filler for polymer composites with a polystyrene matrix

Lignocellulosic fibers have been one of the most used reinforcements for different types of composites. In this context, grape stalks—often discarded in landfills—can be a potential reinforcement for composites. The present study aimed to incorporate in natura and alkali treated grape stalks into the polystyrene (PS) matrix. Initially, the grape stalks were treated with NaOH and 10, 20, and 30 wt % of stalks were added into the PS matrix. The alkaline treatment of the grape stalk fibers promoted the removal of hemicellulose and the partial removal of lignin, thus increasing the surface roughness and crystallinity index of the fibers. An improvement in the mechanical and dynamic-mechanical properties and an increase in the maximum degradation temperature of the composites were observed. In conclusion, the use of grape stalks is a promising alternative for reinforcing composites, and, in addition, a more proper destination can be given to this type of residue. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47427.     

Active packaging solution to prolong the shelf life of rocket salad

The best packaging conditions for rocket salad were assessed by subsequent experimental trials. In the first step, a preliminary screening of different packaging materials was performed and two micro‐perforated oriented polypropylene films with different micro‐hole diameters (90 and 110 μm) were selected as best packaging solutions. In the subsequent experimental step, modified headspace conditions were applied without any improvement on product quality. In the last step, the effects of an ethylene adsorbent were analysed. Rocket salad packaged in both films with the ethylene adsorbent recorded a shelf life of about 16 days, compared to the control samples that remained acceptable for 13 days. During storage, the microbial quality (mesophilic and psychrotrophic bacteria, pseudomonadaceae, lactic acid bacteria, yeasts, total coliforms and enterobacteriacae), the pH, the colour changes and the main sensory parameters were also monitored.     

Optimized production of a high-performance hybrid biomaterial: biomineralized spider silk for bone tissue engineering

Silks have been widely used as biomaterials due to their biocompatibility, biodegradability, and excellent mechanical properties. In the present work, native spider silk was used as organic template for controlled nucleation of hydroxyapatite (HA) nano-coating that can act as biomimetic interface. Different bio-inspired neutralization methods and process parameters were evaluated to optimize the silk functionalization. The morphology and chemical composition were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analysis and mechanical properties were studied through tensile tests. Results showed that the optimized protocol enabled a controlled and homogeneous nucleation of apatite nano-crystals while maintaining silk mechanical performances after mineralization. This study reports the optimization of a simple and effective bio-inspired nucleation process for precise nucleation of HA onto spider silk templates, suitable to develop high-performance hybrid interfaces for bone tissue engineering. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48739.