Perumal Thiagarajan

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Erythroid cells undergo enucleation and the removal of organelles during terminal differentiation. Although autophagy has been suggested to mediate the elimination of organelles for erythroid maturation, the molecular mechanisms underlying this process remain undefined. Here we report a role for a Bcl-2 family member, Nix (also called Bnip3L), in the(More)
Thrombolysis remains a mainstay in the treatment of ischemic stroke. While not usually considered in the spectrum of clot lysis, experimental data show that inhibition of the platelet glycoprotein (GP) IIb/IIIa receptor can reduce as well as reverse thrombus formation and improve microvascular flow in stroke models. However, a recent clinical trial of GP(More)
BACKGROUND Cholesterol 3-sulfate is present on a variety of cells and in human LDL, and it has been found in atherosclerotic lesions of human aorta. Its precise biological role has not yet been described. METHODS AND RESULTS In this study, we investigated the interaction of platelets with cholesterol sulfate. Platelets adhered in a concentration-dependent(More)
On platelets the membrane glycoprotein IIb/IIIa complex (GPIIb/IIIa) functions in adhesive interactions with fibrinogen, von Willebrand factor, and fibronectin. However, the function of GPIIb/IIIa-like proteins on endothelial cells, as well as the ligand(s) the complex binds, is unknown. Using a highly specific polyclonal antibody we have explored the(More)
During prolonged hypoxia, hypoxia-inducible factors (HIFs) mediate an increase in erythropoiesis, leading to an increased red blood cell (RBC) mass and polycythemia. Upon return to normoxia, the increased RBC mass is abruptly overcorrected by the preferential destruction of hypoxia-formed young RBCs, a phenomenon termed neocytolysis. The molecular and(More)
BACKGROUND The transbilayer movement of phosphatidylserine mediates the platelet procoagulant activity during collagen stimulation. The Rho-associated coiled-coil kinase (ROCK) inhibitor Y-27632 inhibits senescence induced but not activation induced phosphatidylserine exposure. To investigate further the specific mechanisms, we now utilized mice with(More)
BACKGROUND Ovarian cancer patients have a high risk of developing venous thrombosis. The membrane lipid bilayer of platelets and platelet-derived microparticles (PMP) provides a platform for assembly of coagulation proteins and generation of blood clots. METHODS We compared the lipid composition of platelets and PMPs in patients with ovarian cancer to(More)
In resting platelets, the integrin αIIbβ3 is present in a low-affinity "bent" state. During platelet aggregation, intracytoplasmic signals induce conformational changes (inside-out signaling) that result in a "swung-out" conformation competent to bind ligands such as fibrinogen. The cytoskeleton plays an essential role in αIIbβ3 activation. We investigated(More)
Refractoriness to growth factor therapy is commonly associated with inferior outcome in patients with low-risk myelodysplastic syndrome (LR-MDS) who require treatment for cytopenias. However, the mechanisms leading to refractoriness are unknown. Here we describe a clinically depressed 74-year-old male with refractory cytopenia with multilineage dysplasia(More)
Drug-induced neutropenia is characterized by a sharp decrease in the absolute neutrophil count (ANC) to <500/mm 3 ; agranulocytosis is said to be present once the granulocyte count reaches zero. Although associated with a large variety of drugs, this adverse effect is rare, occurring in 2.4–15.4 cases per million courses of therapy [1]. Because of its(More)
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