Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of our study was to develop a new carotid thrombosis model with an arterial shear rate close to that prevailing in affected arteries of patients with transient ischemic attacks (TIAs) and moderate carotid stenosis and to test various antithrombotic principles. In anaesthetized guinea pigs, carotid blood flow was monitored by a Doppler flow probe and the vessel was damaged by 2 or 3 brief pinches by a surgical forceps. The intravenous effects of aspirin (20 mg/kg), heparin (200 U/kg) and hirudin (500 micrograms/kg) or Ro 44-9883 (0.2 to 1 mg/kg), a new selective non-peptidic GP IIb-IIIa inhibitor were tested. After the damage, blood flow progressively decreased to zero and could regularly and reproducibly be restored by a mechanical shaking of the artery. The occlusive thrombus consisted mainly of platelet aggregates. The estimated shear rate in the damaged carotid artery was in the range of 1500 to 2800 s-1. The resulting cyclic flow variations (CFVs) were obtained in all the guinea pigs and were abolished in 10%, 20% and 60% of the animals treated with heparin, hirudin and aspirin, respectively. Ro 44-9883 abolished dose dependently the CFVs with 100% abolition at 1 mg/kg. Thus reproducible thrombosis without additional stenosis can be generated in the carotid artery of the guinea pig at a lower shear rate than that prevailing in the classical thrombosis models. GPIIb-IIIa blockade showed a higher curative efficacy than inhibition of the cyclooxygenase pathway or that of thrombin generation either through an antithrombin III dependent or independent mechanism.
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PMID:Experimental carotid thrombosis in the guinea pig. 819 8

Platelet-derived microparticles (PMPs) are released from platelets through the platelet activation by high shear stress, collagen, or calcium ionophore (A23187). PMPs are observed in patients with acute myocardial infarction, thrombotic thrombocytopenic purpura, hemolytic uremic syndrome, heparin-induced thrombocytopenia and other thrombotic disorders, but the importance of circulating PMPs in the pathogenesis of these diseases is still debated. Numbers of PMPs are usually determined by flowcytometry (FCM), but easier and reproducible PMP assay systems are needed. To develop a better ELISA for PMPs, we used antibodies against the platelet antigens anti-GPIb (NNKY5-5), anti-GPIIb/IIIa (NNKY2-11, anti-CD41), anti-GPIX (KMP-9), and anti-CD9 (NNKY1-19). PMPs were detected with all combinations of these antibodies, but the ELISA having the highest and most specific absorbance was obtained with a combination of KMP-9 (capture antibody) and NNKY5-5 (detecting antibody). PMPs in blood samples were measured by ELISA and FCM. ELISA correlated with PMPs quantitated by FCM. By shaking ELISA plates during incubation, nonspecific binding of platelets was eliminated. The level of PMPs was not increased in diabetes mellitus, thrombotic thrombocytopenic purpura, antiphospholipid syndrome, or sepsis. The concentration of PMP was elevated in hemolytic uremic syndrome. Activated PMPs were absorbed to 0.8 microm filter, but circulating PMPs were not absorbed. These results suggest that activated PMPs are likely to adhere to leukocytes or endothelial cells at the activation site and that the circulating form of PMPs are likely to be a residue of activated PMPs. To detect only the activated form of PMPs, a new ELISA needs to be developed, and it will likely use a combination of antibodies that detect platelet activation markers such as P-selectin (CD62P) or activated GPIIb/IIIa.
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PMID:Development and assessment of enzyme immunoassay for platelet-derived microparticles. 1124 56