John V. Mitsios

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OBJECTIVE Platelet-activating factor acetylhydrolase (PAF-AH) expresses a Ca2+-independent phospholipase A2 activity and hydrolyzes platelet-activating factor as well as oxidized phospholipids. Two major types of PAF-AH have been described: the plasma type, which is associated with lipoproteins, and the intracellular type II PAF-AH. METHODS AND RESULTS We(More)
The platelet integrin receptor alphaIIbbeta3 plays a critical role in thrombosis and haemostasis by mediating interactions between platelets and several ligands, primarily fibrinogen. We have previously shown that the synthetic peptide YMESRADRKLAEVGRVYLFL corresponding to residues 313-332 of alphaIIb, is a potent inhibitor of platelet aggregation and(More)
BACKGROUND The antiplatelet effect of clopidogrel may be attenuated by short-term coadministration of lipophilic statins. We investigated whether the coadministration of atorvastatin for 5 weeks in patients with acute coronary syndromes (ACS) could affect the antiplatelet potency of clopidogrel. METHODS AND RESULTS Forty-five hypercholesterolemic patients(More)
alpha(IIb)beta(3), a member of the integrin family of adhesive protein receptors, is the most abundant glycoprotein on platelet plasma-membranes and binds to adhesive proteins via the recognition of short amino acid sequences, for example the ubiquitous RGD motif. However, elucidation of the ligand-binding domains of the receptor remains controversial,(More)
OBJECTIVE Lipoprotein (a) [Lp(a)] is considered an atherogenic lipoprotein, which is also implicated in thrombosis. Lp(a) binds to platelets and modulates the effects of various platelet agonists. Platelet activating factor (PAF) is a potent platelet agonist degraded and inactivated by PAF-acetylhydrolase (PAF-AH), which in plasma is associated with(More)
After neoplastic cells leave the primary tumor and circulate, they may extravasate from the vasculature and colonize tissues to form metastases. β1 integrins play diverse roles in tumorigenesis and tumor progression, including extravasation. In blood cells, activation of β1 integrins can be regulated by "inside-out" signals leading to extravasation from the(More)
Activation of the platelet integrin-receptor alpha(IIb)beta(3) is the final pathway of platelet aggregation, regardless of the initiating stimulus. Many studies suggest that there are several cytoplasmic proteins such as talin and beta(3)-endonexin that bind to N(744)PLY(747) and N(756)ITY(759) motif of the beta(3) cytoplasmic tail and play the major role(More)
Lipoprotein(a) [Lp(a)] may be an independent risk factor for coronary artery disease (CAD). Lp(a) is enriched in platelet activating factor acetylhydrolase (PAF-AH), an enzyme which hydrolyzes and inactivates platelet activating factor (PAF) and oxidized phospholipids that are implicated in atherogenesis. We determined the mass and catalytic properties of(More)
The Arg-Gly-Asp RGD motif of adhesive proteins is recognized by the activated platelet integrin alpha(IIb)beta3. Binding of fibrinogen (Fg) to activated alpha(IIb)beta3 causes platelet aggregation and thrombus formation. Highly constraint cyclic (S,S) -CXaaC- containing peptides incorporating the (S,S) -CDC- and (S,S) -CRC- motifs were tested for their(More)
Several studies over the last years have demonstrated that statins exhibit actions beyond that of lipid-lowering (pleiotropic effects) ranging from improving endothelial function, modulating the inflammatory response, maintaining plaque stability and preventing thrombus formation. Since the interplay among platelets, cells and other components of(More)