Core-shell nanoparticles from fucoidan neoglycans: Synthesis, characterization with capability of glycomimetic ligands for Campylobacter jejuni

Campylobacteriosis produced by Campylobacter jejuni is the main cause of bacterial gastroenteritis worldwide and the binding of this pathogen to fucosylated glycoconjugates expressed on host cells is a determining factor for the infection. The aim of this work was to synthesize and characterize core-shell nanoparticles from fucoidan neoglycans as potential glycomimetic ligands for Campylobacter jejuni. Fucoidan oligosaccharides (OFuc) were obtained by mild hydrolysis of fucoidan. OFuc were separated by ultrafiltration, characterized by dynamic light scattering (DLS), infrared spectroscopy (FTIR), Fluorophore-assisted carbohydrate electrophoresis and lectin recognition. The OFuc1 were then conjugated with bovine serum albumin (BSA) by controlled glycation. The formation of fucosylated BSA (BSA-OFuc1) was confirmed by FTIR, increased surface charge, polyacrylamide gel electrophoresis, mass spectrometry and Ulex europaeus I lectin recognition. Afterwards core-shell BSA/BSA-OFuc1 nanoparticles were obtained by crosslinking. These nanoparticles presented hemispherical form with size and charge distribution of 312.1 ± 3.2 nm and -34.4 ± 0.3 mV respectively and were selectively recognized by C. jejuni by an ELISA-like lectin assay (ELLA). These results revel the potential of core-shell nanoparticles from fucoidan neoglycans as glycomimetic ligands for Campylobacter jejuni and open further opportunities to explore potential applications in the pharmaceutic industry

Abscisic Acid Activates the Murine Microglial Cell Line N9 through the Second Messenger Cyclic ADP-ribose*

Abscisic acid (ABA) is a phytohormone regulating important functions in higher plants, notably responses to abiotic stress. Recently, chemical or physical stimulation of human granulocytes was shown to induce production and release of endogenous ABA, which activates specific cell functions. Here we provide evidence that ABA stimulates several functional activities of the murine microglial cell line N9 (NO and tumor necrosis factor-α production, cell migration) through the second messenger cyclic ADP-ribose and an increase of intracellular calcium. ABA production and release occur in N9 cells stimulated with bacterial lipopolysaccharide, phorbol myristate acetate, the chemoattractant peptide f-MLP, or β-amyloid, the primary plaque component in Alzheimer disease. Finally, ABA priming stimulates N9 cell migration toward β-amyloid. These results indicate that ABA is a pro-inflammatory hormone inducing autocrine microglial activation, potentially representing a new target for anti-inflammatory therapies aimed at limiting microglia-induced tissue damage in the central nervous system

Global attitudes in the management of acute appendicitis during COVID-19 pandemic: ACIE Appy Study

Background: Surgical strategies are being adapted to face the COVID-19 pandemic. Recommendations on the management of acute appendicitis have been based on expert opinion, but very little evidence is available. This study addressed that dearth with a snapshot of worldwide approaches to appendicitis. Methods: The Association of Italian Surgeons in Europe designed an online survey to assess the current attitude of surgeons globally regarding the management of patients with acute appendicitis during the pandemic. Questions were divided into baseline information, hospital organization and screening, personal protective equipment, management and surgical approach, and patient presentation before versus during the pandemic. Results: Of 744 answers, 709 (from 66 countries) were complete and were included in the analysis. Most hospitals were treating both patients with and those without COVID. There was variation in screening indications and modality used, with chest X-ray plus molecular testing (PCR) being the commonest (19\ub78 per cent). Conservative management of complicated and uncomplicated appendicitis was used by 6\ub76 and 2\ub74 per cent respectively before, but 23\ub77 and 5\ub73 per cent, during the pandemic (both P < 0\ub7001). One-third changed their approach from laparoscopic to open surgery owing to the popular (but evidence-lacking) advice from expert groups during the initial phase of the pandemic. No agreement on how to filter surgical smoke plume during laparoscopy was identified. There was an overall reduction in the number of patients admitted with appendicitis and one-third felt that patients who did present had more severe appendicitis than they usually observe. Conclusion: Conservative management of mild appendicitis has been possible during the pandemic. The fact that some surgeons switched to open appendicectomy may reflect the poor guidelines that emanated in the early phase of SARS-CoV-2