Objectives: Suggested therapeutic options for Multisystem Inflammatory Syndrome in Children (MIS-C) include intravenous immunoglobulins (IVIG) and steroids. Prior studies have shown the benefit of combination therapy with both agents on fever control or the resolution of organ dysfunction. The primary objective of this study was to analyze the impact of IVIG and steroids on hospital and ICU length of stay (LOS) in patients with MIS-C associated with Coronavirus Disease 2019 (COVID-19).

Herein, we report a novel liquid chromatography coupled with tandem mass spectrometry method to characterize N-acetylneuraminic acid (Neu5Ac, Sa) linkage in N-linked glycans in glycopeptides with no sialic acid derivatization. First, we established a separation in reversed-phase high-performance liquid chromatography (HPLC) using a higher formic acid concentration in the mobile phases, which separated the N-glycopeptides depending on the Sa linkage. We also demonstrated a novel characterization method of Sa linkages in N-glycopeptides using electron-activated dissociation. We found that hot electron capture dissociation using an electron beam energy higher than 5 eV cleaved glycosidic bonds in glycopeptides, resulting in each glycosidic bond in the antennas being broken on both sides of the oxygen atom. Such glycosidic bond cleavage at the reducing end (C-type ion) showed the difference in Sa linkages between Sa-Gal, Gal-GlcNAc, and GlcNAc-Man. We proposed a rule to characterize the Sa linkages using the Sa-Gal products. This method was applied to N-glycopeptides in tryptic fetuin digest separated by an optimized reversed-phase HPLC. We successfully identified a number of isomeric glycoforms in the glycopeptides with different Sa links, whose peptide backbones were also simultaneously sequenced by hot ECD.

Preoperative endovascular embolization is not feasible in some cases due to the location of the segmental or radiculomedullary arteries in relation to tumor feeders and, rarely, small size of these arterial feeders. Percutaneous injection of onyx is an option. In this case report, we discuss direct intraoperative injection via a transpedicular route as a safe and effective method for decreasing the vascularity of some lesions and improving intraoperative blood loss.

No abstract