Search results for "Platelet Aggregation"

Spontaneous echo contrast imaging in infective endocarditis: a predictor of complications?

1992

Infective endocarditis is associated with significant morbidity and mortality. Valvular destruction and congestive heart failure are more common in patients with echocardiographically detectable vegetations. In addition, spontaneous platelet aggregation is increased when vegetations are present on cardiac valves. The aim of the study was to assess the prognostic value of spontaneous echo contrast (SEC) imaging, as SEC is supposed to reflect red blood cell aggregates stimulated by platelet activity. We studied 293 patients with clinical signs of infective endocarditis. Vegetations, attached to the aortic or mitral valve, were found in 130 patients (44.4%) who were followed for a mean period …

Inhibition of thromboxane biosynthesis by triflusal in type 2 diabetes mellitus.

2004

Abstract Triflusal is an antiplatelet drug related to aspirin, with different pharmacological properties and a lower haemorrhagic risk. We aimed at comparing their effects on platelet and endothelial activation in type 2 diabetes mellitus (T2DM). In a randomized, double-blind, parallel group study, we compared the effects of three daily regimens (300, 600, and 900mg) of triflusal, and aspirin (100mg/day) on urinary 11-dehydro-thromboxane (TX)B 2 , index of in vivo platelet activation, ex vivo platelet function using the analyzer PFA-100, plasma von Willebrand factor (vWF), P-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and serum nitrite a…

Immediate versus delayed facilitated percutaneous coronary intervention. A pilot study

2005

The study was aimed to investigate the outcomes in patients initially successfully treated pharmacologically and immediate PCI <2 hours, and in patients initially successfully treated with pharmacological therapy and delayed PCI (12-72 hours). All patients had to have successful reperfusion, to receive the combination of a standard abciximab infusion plus half dose rtPA. Similar results were observed in both groups. Delayed PCI group showed a favorable trend in restenosis and bleedings (ns) and a significant reduced angiographic evidence of thrombus formation in IRA. Our very preliminary data suggest the safety and possible use of delayed facilitated PCI in patients with STEMI. The studied …

Patent foramen ovale closure in stroke patients with migraine in the CLOSE trial. The CLOSE-MIG study.

2021

International audience; Background and purpose The efficacy of patent foramen ovale (PFO) closure to reduce the frequency of migraine attacks remains controversial. Methods This was a planned sub-study in migraine patients enrolled in a randomized, clinical trial designed to assess the superiority of PFO closure plus antiplatelet therapy over antiplatelet therapy alone to prevent stroke recurrence in patients younger than 60 years with a PFO-associated cryptogenic ischaemic stroke. The main outcome was the mean annual number of migraine attacks in migraine patients with aura and in those without aura, as recorded at each follow-up visit by study neurologists. Results Of 473 patients randomi…

Platelets, eicosanoids and aging.

1992

Prostacyclin receptor desensitization is a reversible phenomenon in human platelets.

1997

Background Long-term exposure of platelets to endogenous or exogenous prostacyclin or its analogues might result in desensitization of the platelet prostacyclin receptor in vitro and in vivo accompanied by a loss in receptor density on the platelet surface and a reduced sensitivity toward the inhibitory effects of prostacyclins. However, the reversibility of this process in platelets has not yet been investigated. Methods and Results Human platelets desensitized by the chemically stable prostacyclin analogue iloprost showed a significant reduction in [ 3 H]-iloprost binding sites that was reversed by saponin permeabilization. This indicates functionally active internalized prostacyclin rec…

Effects of pathogen reduction systems on platelet microRNAs, mRNAs, activation, and function

2014

Pathogen reduction (PR) systems for platelets, based on chemically induced cross-linking and inactivation of nucleic acids, potentially prevent transfusion transmission of infectious agents, but can increase clinically significant bleeding in some clinical studies. Here, we documented the effects of PR systems on microRNA and mRNA levels of platelets stored in the blood bank, and assessed their impact on platelet activation and function. Unlike platelets subjected to gamma irradiation or stored in additive solution, platelets treated with Intercept (amotosalen + ultraviolet-A [UVA] light) exhibited significantly reduced levels of 6 of the 11 microRNAs, and 2 of the 3 anti-apoptotic mRNAs (B…

Initiation and duration of dual antiplatelet therapy after inpatient percutaneous coronary intervention with stent implantation in Germany: An electr…

2017

Abstract Background Studies assessing the routine outpatient dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in Germany are scarce. The aim of this study was (i) to investigate the initiation and duration of DAPT after inpatient PCI with stent implantation in Germany, and (ii) to identify factors associated with DAPT discontinuation during the recommended treatment period. Methods This retrospective cohort study was based on data from a large German electronic healthcare database of the years 2004 to 2009. The study population comprised four groups of patients with acute coronary syndrome (ACS) or stable angina pectoris undergoing inpatient PCI with either ba…

The Serine/Threonine Protein Phosphatase 2A (PP2A) Regulates Syk Activity in Human Platelets

2020

Distinct membrane receptors activate platelets by Src-family-kinase (SFK)-, immunoreceptor-tyrosine-based-activation-motif (ITAM)-dependent stimulation of spleen tyrosine kinase (Syk). Recently, we reported that platelet activation via glycoprotein (GP) VI or GPIb&alpha

Native, Intact Glucagon-Like Peptide 1 Is a Natural Suppressor of Thrombus Growth Under Physiological Flow Conditions

2020

Objective: In patients with diabetes mellitus, increased platelet reactivity predicts cardiac events. Limited evidence suggests that DPP-4 (dipeptidyl peptidase 4) influences platelets via GLP-1 (glucagon-like peptide 1)-dependent effects. Because DPP-4 inhibitors are frequently used in diabetes mellitus to improve the GLP-1-regulated glucose metabolism, we characterized the role of DPP-4 inhibition and of native intact versus DPP-4-cleaved GLP-1 on flow-dependent thrombus formation in mouse and human blood. Approach and Results: An ex vivo whole blood microfluidics model was applied to approach in vivo thrombosis and study collagen-dependent platelet adhesion, activation, and thrombus for…