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Anticoagulant Used (anticoagulant + used)
Selected AbstractsHarmonization of light scatter and fluorescence flow cytometry profiles obtained after staining peripheral blood leucocytes for cell surface-only versus intracellular antigens with the Fix & PermÔ reagent,,§CYTOMETRY, Issue 1 2010Elaine Sobral da Costa Abstract Staining for intracellular markers with the Fix & PermÔ reagent is associated with variations in the scatter properties of leucocytes, limiting automated analysis of flow cytometry (FCM) data. Here, we investigated those variables significantly contributing to changes in the light scatter, autofluorescence, and bcl2 staining characteristics of peripheral blood (PB) leucocytes, after fixation with Fix & PermTM. Our major aim was to evaluate a new mathematical approach for automated harmonization of FCM data from datafiles corresponding to aliquots of a sample treated with cell-surface-only versus Fix & Perm intracellular staining techniques. Overall, neither the anticoagulant used nor sample storage for <24 h showed significant impact on the light scatter and fluorescence properties of PB leucocytes; similarly, the duration of the fixation period (once >15 min were used) had a minimum impact on the FCM properties of PB leucocytes. Conversely, changes in cell/protein concentrations and the fixative/sample (vol/vol) ratio had a clear impact on the light scatter features of some populations of leucocytes. Accordingly, lower cell/protein concentrations were associated with lower scatter values, particularly for the neutrophils. Such changes could be partially corrected through the use of higher fixative to sample volume ratios. Despite the variable changes detected between aliquots of the same sample treated with cell surface-only versus intracellular staining procedures, the new mathematical approach here proposed and evaluated for automated harmonization of common parameters in both datafiles, could correct the FCM profiles of leucocytes derived from cells undergoing conventional fixation/permeabilization procedures, and made them indistinguishable from those corresponding to aliquots of the same sample treated with cell-surface-only staining techniques. © 2009 Clinical Cytometry Society [source] Selection of glycoprotein IIb/IIIa inhibitors for upstream use in patients with diabetes experiencing unstable angina or non-ST segment elevation myocardial infarction.JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 6 2004What have we learned in the last 10 years? Summary Coronary disease accounts for the majority of deaths among patients with diabetes and the thrombotic milieu accelerated by diabetes results in unstable angina (UA), non-ST segment elevation myocardial infarction (NSTEMI) or ST-segment elevation myocardial infarction (STEMI) or death. Upstream use of a glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitor with percutaneous coronary intervention (PCI) as part of an early invasive approach is preferred. However substantial numbers of patients present to rural or non-teaching hospitals without immediate access to a catheterization laboratory. Enhanced GP IIb/IIIa receptor mobilization, TXA2 production and platelet activation together present an extensive thrombotic challenge that may not be overcome with current doses of GP IIb/IIIa inhibitors when used without PCI. Heterogeneity of platelet aggregometric analysis may have identified GP IIb/IIIa doses used in clinical trials that may not fully overcome the thrombotic challenge in patients with diabetes. GUSTO-IV ACS failed to demonstrate a difference in mortality when used without PCI. The PURSUIT trial provided evidence that eptifibatide decreases death or non-fatal myocardial infarction (MI) in the main group and in the diabetic subgroup. Reductions in this primary endpoint were driven by the reduction in non-fatal MI. The PRISM and PRISM-PLUS trials demonstrated a reduction in death, MI or refractory ischaemia at 48 h or 7 days in the main cohort but not specifically in patients with diabetes. Data supporting use of GP IIb/IIIa inhibitors are inconsistent, raising the question of whether these agents should be used at all without PCI. Variability in experimental methodology of platelet aggregometry and selection of anticoagulant used during dose finding studies may have generated doses that are insufficient to overcome the thrombotic burden. A new marker of active inflammation, sCD40L is found to be upregulated at subtherapeutic doses of GP IIb/IIIa inhibitors, suggesting that rebound inflammatory processes may partially account for absence of clear evidence of benefit with some GP IIb/IIIa inhibitors in patients with diabetes experiencing UA/NSTEMI. [source] Non-fatal major bleeding during treatment with vitamin K antagonists: influence of soluble thrombomodulin and mutations in the propeptide of coagulation factor IXJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2004J. F. Van Der Heijden Summary., Background and objectives : The key complication of treatment with vitamin K antagonists (VKAs) is bleeding. The major determinant of VKA-induced bleeding is the intensity of anticoagulation. Individual patient characteristics may also influence bleeding risk. In addition, soluble thrombomodulin (s-TM) levels and mutations in the propeptide of factor (F)IX are important candidate risk factors in this respect. Patients and methods : A matched case,control study was designed to search for risk factors that predict bleeding during VKA treatment. We selected cases that had experienced major bleeding during treatment with VKA and matched controls without bleeding complications from the databases of two Thrombosis Services. The controls were matched for indication of treatment, age, gender, type of anticoagulant used and whether or not treatment with VKA was stopped. DNA and plasma were stored of all cases and controls. Results and conclusions : In total 110 patients and 220 controls consented to participate. The results indicate that s-TM levels, measured by ELISA, may be a risk indicator for bleeding [crude odds ratio 3.25 for the highest quartile vs. the lowest quartile (95% confidence interval 1.40, 7.51)]. Three novel mutations, determined by direct sequencing, in the gene portion encoding the propeptide of FIX were identified that do not seem to play an important role in bleeding risk during treatment with VKAs. [source] Importance of Uniform Heparin Coating on BiopolymersARTIFICIAL ORGANS, Issue 3 2000Patrícia Da Luz Moreira Abstract: Cardiopulmonary surgeries need connectors for extracorporeal circulation. The patient's blood in contact with the tube surfaces modifies its plasmatic proteins, promotes platelet aggregation, and activates the complement system, unleashing thrombus formation. Thus, it becomes necessary for an anticoagulant to keep the circuit free from these events. Heparin is the anticoagulant used even after reports about its disadvantages. Platelet adherence seems to be very dependent on the quality from the surfaces that can promote cellular proliferation, aggregation, and thrombosis. In this study, we compare the quality of the heparin-coated and uncoated surfaces. We used a blood cell culture and scanning electron microscopy (SEM) to visualize the platelet aggregation. It was concluded that there are groove areas that permit platelet adherence, and if they are not coated totally by the heparin, aggregation still occurs although in lower scale than on the uncoated tubes. [source] | ||||||||||