Search results for "Platelet"
showing 10 items of 786 documents
HIF-1α and HIF-2α Are Differentially Regulated In vivo in Neuroblastoma: High HIF-1α Correlates Negatively to Advanced Clinical Stage and Tumor Vascu…
2009
Abstract Purpose: Hypoxia is considered to be a major driving force behind tumor angiogenesis. The stabilization and activation at hypoxia of the hypoxia-inducible factors HIF-1α and HIF-2α and the concomitant induction of expression of vascular endothelial growth factor (VEGF) and other proangiogenic factors provide a molecular frame for hypoxia-driven tumor angiogenesis. This study has investigated how HIF and VEGF protein levels relate to each other with regard to vascularization, tumor stage, and overall survival in neuroblastoma. Experimental Design: Tissue cores taken from tumor specimens representing 93 children with neuroblastoma were arranged on a microarray and stained for HIF-1α,…
Angiogenesis in Wounds Treated by Microdeformational Wound Therapy.
2011
BACKGROUND:: Mechanical forces play an important role in tissue neovascularization and are a constituent part of modern wound therapies. The mechanisms by which vacuum assisted closure (VAC) modulates wound angiogenesis are still largely unknown. OBJECTIVE:: To investigate how VAC treatment affects wound hypoxia and related profiles of angiogenic factors as well as to identify the anatomical characteristics of the resultant, newly formed vessels. METHODS:: Wound neovascularization was evaluated by morphometric analysis of CD31-stained wound cross-sections as well as by corrosion casting analysis. Wound hypoxia and mRNA expression of HIF-1α and associated angiogenic factors were evaluated by…
Characterization of New Organic Nitrate Hybrid Drugs Covalently Bound to Valsartan and Cilostazol
2012
Background and Purpose: Organic nitrates represent a group of nitrovasodilators that are clinically used for the treatment of ischemic heart disease. With the present studies we synthesized and characterized new organic nitrate hybrid molecules. Compounds CLC-1265 (valsartan mononitrate) and CLC-1280 (valsartan dinitrate) are derivatives of the angiotensin receptor blocker valsartan, with CLC-1265 containing a single organic nitrate linker and CLC-1280 also containing a second, different linker. Compounds CLC-2000 (cilostazol mononitrate) and CLC-2100 (cilostazol dinitrate) are nitrate derivatives of the phosphodiesterase III inhibitor cilostazol. All compounds are designed as hybrid molecu…
Antithrombotic Therapy in Patients with Atrial Fibrillation and Acute Coronary Syndrome Treated Medically or with Percutaneous Coronary Intervention …
2019
Background: The safety and efficacy of antithrombotic regimens may differ between patients with atrial fibrillation who have acute coronary syndromes (ACS), treated medically or with percutaneous coronary intervention (PCI), and those undergoing elective PCI. Methods: Using a 2×2 factorial design, we compared apixaban with vitamin K antagonists and aspirin with placebo in patients with atrial fibrillation who had ACS or were undergoing PCI and were receiving a P2Y 12 inhibitor. We explored bleeding, death and hospitalization, as well as death and ischemic events, by antithrombotic strategy in 3 prespecified subgroups: patients with ACS treated medically, patients with ACS treated with PCI,…
Perioperative risk of bleeding with antithrombotic agents in macular surgery: a national, prospective, multicentre study
2020
International audience; Purpose To compare the risk of haemorrhagic complications in elective macular surgery between patients with no antithrombotic (AT) treatment (defined as patients with no history of AT therapy or who discontinued AT therapy) and patients who continued AT treatment during the surgery. Methods E-case report forms were prospectively recorded in a database before vitreoretinal surgery and 1 month after. Data on patient characteristics, surgical techniques, haemorrhagic complications and antithrombotic status were collected. Patients with retinal detachment, proliferative diabetic retinopathy and previous retinal haemorrhage were excluded. Results A total of 748 procedures…
Two new cases of Thrombocytopenia Absent Radius (TAR) syndrome: Clinical, Genetic and Nosologic Features
1988
Two unrelated children affected by TAR syndrome, autosomic recessive disease with congenital thrombocytopenia and bilateral radial aplasia, are described. In the first case a mild thrombocytopenia has been compatible with a fairly normal life until the second year of age. The other child shows radial aplasia associated with other anomalies of the upper limbs, severe thrombocytopenia and leukemoid reaction. The relationship among TAR syndrome, Fanconi's anemia and Roberts' syndrome are briefly discussed.
Does the NO/sGC/cGMP/PKG pathway play a stimulatory role in platelets?
2012
Nitric oxide (NO) stimulates cGMP synthesis by activating its intracellular receptor, soluble guanylyl cyclase (sGC). It is a currently prevailing concept that No and cGMP inhibits platelet function. However, the data supporting the inhibitory role of NO/sGC/cGMP in platelets have been obtained either in vitro or using whole body gene deletion that affects vessel wall function. Here we have generated mice with sGC gene deleted only in megakaryocytes and platelets. Using the megakaryocyte- and platelet-specific sGC-deficient mice, we identify a stimulatory role of sGC in platelet activation and in thrombosis in vivo. Deletion of sGC in platelets abolished cGMP production induced by either NO…
''Circulating and Brain BDNF Levels in Stroke Rats. Relevance to Clinical Studies''
2011
International audience; ''Background: Whereas brain-derived neurotrophic factor (BDNF) levels are measured in the brain in animal models of stroke, neurotrophin levels in stroke patients are measured in plasma or serum samples. The present study was designed to investigate the meaning of circulating BDNF levels in stroke patients. Methods and Results: Unilateral ischemic stroke was induced in rats by the injection of various numbers of microspheres into the carotid circulation in order to mimic the different degrees of stroke severity observed in stroke patients. Blood was serially collected from the jugular vein before and after (4 h, 24 h and 8 d) embolization and the whole brains were co…
Potent low dose platelet inhibitory effects of clopidogrel and aspirin on coronary thrombus formation in an animal model of acute unstable angina
2006
SummaryApplication of clopidogrel before percutaneous coronary intervention in patients with acute coronary syndrome reduces the risk of cardiac events. Clopidogrel administration before surgery increases bleeding complications after CABG. Therefore, the antithrombotic effect of the low-dose combination of clopidogrel and aspirin was investigated in an in vivo pig model of coronary artery thrombus formation with cyclic flow reductions. The platelet inhibitory effect was determined by platelet aggregation and CFR, according to the methodology described by Folts. CFR were initiated by endothelial damage and placement of a constrictor around the LAD. 30 min after CFR were established, clopidog…
Antithrombotic Therapy after Acute Coronary Syndrome or PCI in Atrial Fibrillation
2019
Background: Appropriate antithrombotic regimens for patients with atrial fibrillation who have an acute coronary syndrome or have undergone percutaneous coronary intervention (PCI) are unclear. Methods: In an international trial with a two-by-two factorial design, we randomly assigned patients with atrial fibrillation who had an acute coronary syndrome or had undergone PCI and were planning to take a P2Y12 inhibitor to receive apixaban or a vitamin K antagonist and to receive aspirin or matching placebo for 6 months. The primary outcome was major or clinically relevant nonmajor bleeding. Secondary outcomes included death or hospitalization and a composite of ischemic events. Results: Enroll…