SARS-CoV-2 (Severe Acute Respiratory Syndrome-related CoronaVirus 2) activates the immune system, causing thrombin dysregulation and tissue damage and reduces endothelium anticoagulant function, leading to excessive thrombin formation. Hypercoagulability, which causes multiple organ failure in critically ill COVID-19 (COronaVIrus Disease 2019) patients, can be detected by viscoelastic tests like thromboelastography and rotational thromboelastometry (ROTEM). We aimed to assess the coagulation system status and fibrinolytic activity using ROTEM thromboelastometry in patients with COVID-19 and convalescents.
View Article and Find Full Text PDFThe investigation of common inflammation mechanisms caused by exogenic compounds of microbial origin and allergens is one of the most important tasks in current biomedical science. The main manifestations of immune cell activation caused by pro-inflammatory agents are changes in receptor quantity on the surface of immune cells and the production of cytokines and chemokines by blood cells. The levels of expression of TLR4, CD14, and CD11b in the monocytes and neutrophils of human whole blood in response to LPS , Der p 2 allergen, or their combination reflect different functional activities in these cells, while the composition and amount of produced cytokines reflect the biological activity of the studied agonists.
View Article and Find Full Text PDFLipopolysaccharides (LPS) and lipoteichoic acids (LTA) are the major inducers of the inflammatory response of blood cells caused by Gram-negative and some Gram-positive bacteria. CD14 is a common receptor for LPS and LTA that transfers the ligands to TLR4 and TLR2, respectively. In this work, we have demonstrated that the non-toxic LPS from Rhodobacter capsulatus PG blocks the synthesis of pro-inflammatory cytokines during the activation of blood cells by Streptococcus pyogenes LTA through binding to the CD14 receptor, resulting in the signal transduction to TLR2/TLR6 being blocked.
View Article and Find Full Text PDFBy combining the well-known grid reflection method with a digital image correlation algorithm and a geometrical optics model, a new method is proposed for measuring the change of curvature of a smooth reflecting substrate, a common reporter of stress state of deposited layers. This tool, called Pattern Reflection for Mapping of Curvature (PReMC), can be easily implemented for the analysis of the residual stress during deposition processes and is sufficiently accurate to follow the compressive-tensile-compressive stress transition during the sputtering growth of a Ag film on a Si substrate. Unprecedented resolution below 10mcan be reached when measuring a homogeneous curvature.
View Article and Find Full Text PDFLipopolysaccharides (LPSs or endotoxins) from Gram-negative bacteria represent pathogen-associated molecular patterns (PAMPs) that are recognized by CD14 and Toll-like receptor 4 (TLR4). Lipopolysaccharides prime polymorphonuclear leukocytes (PMNs) for substantial production of reactive oxygen species (ROS) during its response to secondary stimuli such as chemoattractants or pathogens. The excessive ROS production can damage surrounding host tissues, thereby amplifying the inflammatory reaction caused by pathogens.
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