Search results for "Platelet"

The pleiotropic effects of antiplatelet therapies

2019

Percutaneous coronary intervention is the most often used method for coronary revascularization. Stenting restores blood perfusion to ischemic areas, but it also causes mechanical disruption of the atheromatous plaque and the nearby endothelium, stimulating the activation of platelets. In a similar way, platelets are activated by thrombin exposure in the setting of plaque rupture. The interaction between platelets, oxidative stress and inflammation is an important factor determining the extent and severity of vascular dysfunction observed in these settings. Platelets activated by the vessel trauma release inflammatory and mitogenic mediators into the vascular microenvironment, activating le…

COVID-19 disease - Temporal analyses of complete blood count parameters over course of illness, and relationship to patient demographics and manageme…

2020

Background Detailed temporal analyses of complete (full) blood count (CBC) parameters, their evolution and relationship to patient age, gender, co-morbidities and management outcomes in survivors and non-survivors with COVID-19 disease, could identify prognostic clinical biomarkers. Methods From 29 January 2020 until 28 March 2020, we performed a longitudinal cohort study of COVID-19 inpatients at the Italian National Institute for Infectious Diseases, Rome, Italy. 9 CBC parameters were studied as continuous variables [neutrophils, lymphocytes, monocytes, platelets, mean platelet volume, red blood cell count, haemoglobin concentration, mean red blood cell volume and red blood cell distribu…

Graphene coating obtained in a cold-wall CVD process on the Co-Cr Alloy (L-605) for medical applications

2021

Graphene coating on the cobalt-chromium alloy was optimized and successfully carried out by a cold-wall chemical vapor deposition (CW-CVD) method. A uniform layer of graphene for a large area of the Co-Cr alloy (discs of 10 mm diameter) was confirmed by Raman mapping coated area and analyzing specific G and 2D bands

Colloidal Nanoplatelet/Conducting Polymer Hybrids: Excitonic And Material Properties

2016

WOS:000370678700053 Here we present the first account of conductive polymer/colloidal nanoplatelet hybrids. For this, we developed DEH-PPV-based polymers with two different anchor groups (sulfide and amine) acting as surfactants for CdSe nanoplatelets, which are atomically flat semiconductor nanocrystals. Hybridization of the polymers with the nanoplatelets in the solution phase was observed to cause strong photoluminescence quenching in both materials. Through steady-state photoluminescence and excitation spectrum measurements, photoluminescence quenching was shown to result from dominant exciton dissociation through charge transfer at the polymer/nanoplatelet interfaces that possess a sta…

Factors Associated with Mortality in Patients Experiencing First Episodes of Acquired Thrombotic Thrombocytopenic Purpura (aTTP). Results of the Span…

2019

Introduction: Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare, but life-threatening, hematological disorder characterized by severe thrombocytopenia, hemolytic microangiopathic anemia, and frequent organ damage. The underlying pathophysiology of aTTP is a functional deficiency of plasma ADAMTS13 activity caused by antibodies directed against the ADAMTS13 protease. Despite plasma exchange (PEX) and immunosuppression with corticosteroids, and, more recently, rituximab, which achieve remission in most patients with aTTP, 10-20% of patients are refractory to treatment and die as a result of disease progression. Most of such deaths occur during first episodes of aTTP, as subsequent…

Flow cytometric kinetic assay of calcium mobilization in whole blood platelets using Fluo-3 and CD41

1999

Background: Platelet activation plays a major role in the physiology and pathology of hemostasis. Flow cytometry is a promising approach for the structural and functional analysis of platelets. However, the choice of adequate biological parameters and most technical issues are still under discussion. A rise in cytosolic free Ca 21 is a key early event that follows platelet stimulation and precedes several activation responses, including shape change, aggregation, secretion, and expression of procoagulant activity. Our objective was to set up a fast and sensitive flow cytometric method to determine the kinetics of intracellular Ca 21 mobilization in platelets, which could be performed with t…

β1-Integrin Cytoplasmic Subdomains Involved in Dominant Negative Function

1998

The beta1-integrin cytoplasmic domain consists of a membrane proximal subdomain common to the four known isoforms ("common" region) and a distal subdomain specific for each isoform ("variable" region). To investigate in detail the role of these subdomains in integrin-dependent cellular functions, we used beta1A and beta1B isoforms as well as four mutants lacking the entire cytoplasmic domain (beta1TR), the variable region (beta1COM), or the common region (beta1 deltaCOM-B and beta1 deltaCOM-A). By expressing these constructs in Chinese hamster ovary and beta1 integrin-deficient GD25 cells (Wennerberg et al., J Cell Biol 132, 227-238, 1996), we show that beta1B, beta1COM, beta1 deltaCOM-B, a…

Spontaneous hepatic fibrosis in transgenic mice overexpressing PDGF-A.

2008

Platelet derived growth factor (PDGF) plays a central role in repair mechanisms after acute and chronic tissue damage. To further evaluate the role of PDGF-A in liver fibrogenesis in vivo, we generated transgenic mice with hepatocyte-specific overexpression of PDGF-A using the CRP-gene promoter. Transgenic but not wildtype mice showed expression of PDGF-A mRNA in the liver. Hepatic PDGF-A overexpression was accompanied by a significant increase in hepatic procollagen III mRNA expression as well as TGF-beta1 expression. Liver histology showed increased deposition of extracellular matrix in transgenic but not in wildtype mice. PDGF-A-transgenic mice showed positive sinusoidal staining for alp…

Germline JAK2 L611S mutation in a child with thrombocytosis

2018

Genotypic study of Citrobacter koseri , an emergent platelet contaminant since 2012 in France

2019

International audience; Background: Transfusion-transmitted bacterial infection is a rare occurrence but the most feared complication in transfusion practices. Between 2012 and 2017, five cases of platelet concentrates (PCs) contaminated with the bacterial pathogen Citrobacter koseri (PC-Ck) have been reported in France, with two leading to the death of the recipients. We tested the possibilities of the emergence of a PC-specific clone of C. koseri (Ck) and of specific bacterial genes associated with PC contamination.Study design and methods: The phylogenetic network, based on a homemade Ck core genome scheme, inferred from the genomes of 20 worldwide Ck isolates unrelated to PC contaminati…