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Erythrocyte Aggregation (erythrocyte + aggregation)
Selected AbstractsRheological determinants of red blood cell aggregation in diabetic patients in relation to their metabolic controlDIABETIC MEDICINE, Issue 2 2002K. Elishkevitz Abstract Aims To determine whether increased red blood cell adhesiveness/aggregation in diabetic patients is related to the extent of their metabolic control. Methods We measured erythrocyte adhesiveness/aggregation in a group of 85 adult patients with diabetes mellitus by using citrated venous whole blood and a simple slide test. The erythrocyte adhesiveness/aggregation was determined by measuring the size of the spaces that are formed between the aggregated erythrocytes. We divided the patients into those with either low or high erythrocyte adhesiveness/aggregation values. Results The erythrocyte adhesiveness/aggregation values of the two groups differed significantly in terms of their fibrinogen concentration, erythrocyte sedimentation rate, high sensitive C-reactive protein (CRP), total cholesterol and triglyceride concentrations. There was no difference between the two groups regarding the concentrations of HbA1c. Logistic regression was applied to construct a model to predict the belonging of a patient in the low or high erythrocyte adhesiveness/aggregation group. A linear regression was applied to construct a model to predict the erythrocyte adhesiveness/aggregation values. Both models turned out to include gender, age, fibrinogen, triglyceride, retinopathy, coronary artery disease and age and gender interaction. Neither HbA1c nor CRP entered the models. Conclusions The degree of erythrocyte adhesiveness/aggregation and several variables of the acute-phase response in patients with diabetes mellitus are not directly related to the degree of metabolic control as evaluated by means of HbA1c concentration. Diabetic patients might benefit from rheological or anti-inflammatory interventions regardless of their metabolic control. [source] The erythrocyte adhesiveness/aggregation test for the detection of an acute phase response and for the assessment of its intensityINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2002N. Maharshak Summary We have developed a simple slide test and image analysis to reveal the state of erythrocyte adhesiveness/aggregation in the peripheral blood of patients with various degrees of the humoral acute phase response. The significant correlation between the results of the erythrocyte adhesiveness/aggregation test (EAAT), the erythrocyte sedimentation rate and fibrinogen concentration support the notion that it is possible to use the EAAT as a marker for the intensity of the acute phase response. Within a group of 860 individuals, we were able to differentiate effectively between groups of patients with a different intensity of humoral acute phase response. The present study confirms previous observations that support the applicability of the EAAT to routine clinical practice. [source] Prognostic implications of admission inflammatory profile in acute ischemic neurological eventsACTA NEUROLOGICA SCANDINAVICA, Issue 4 2002T. Anuk Anuk T, Assayag EB, Rotstein R, Fusman R, Zeltser D, Berliner S, Avitzour D, Shapira I, Arber N, Bornstein NM. Prognostic implications of admission inflammatory profile in acute ischemic neurological events. Acta Neurol Scand 2002: 106: 196,199. © Blackwell Munksgaard 2002. Objective, To reveal the potential prognostic implications of admission inflammatory markers in patients with acute ischemic neurological events. Patients and methods, Sixty patients with an acute ischemic neurological event who were examined within 24 h from the appearance of symptomatology. We determined the high-sensitive C-reactive protein (hs-CRP) concentrations, erythrocyte sedimentation rate (ESR), fibrinogen concentrations and degree of erythrocyte adhesiveness/aggregation. Results, A significant correlation was noted between baseline hs-CRP concentrations, ESR as well as adhesiveness/aggregation and the outcome of the ischemic neurological event as determined by the modified Rankin scale 8,12 months following the insult. Conclusion, Admission inflammatory markers have long-term prognostic implications in patients with acute ischemic neurological events. These findings are relevant in view of the new therapeutic interventions now available for reducing the inflammatory response. [source] Mechanisms of fibrinogen-induced microvascular dysfunction during cardiovascular diseaseACTA PHYSIOLOGICA, Issue 1 2010D. Lominadze Abstract Fibrinogen (Fg) is a high molecular weight plasma adhesion protein and a biomarker of inflammation. Many cardiovascular and cerebrovascular disorders are accompanied by increased blood content of Fg. Increased levels of Fg result in changes in blood rheological properties such as increases in plasma viscosity, erythrocyte aggregation, platelet thrombogenesis, alterations in vascular reactivity and compromises in endothelial layer integrity. These alterations exacerbate the complications in peripheral blood circulation during cardiovascular diseases such as hypertension, diabetes and stroke. In addition to affecting blood viscosity by altering plasma viscosity and erythrocyte aggregation, growing experimental evidence suggests that Fg alters vascular reactivity and impairs endothelial cell layer integrity by binding to its endothelial cell membrane receptors and activating signalling mechanisms. The purpose of this review is to discuss experimental data, which demonstrate the effects of Fg causing vascular dysfunction and to offer possible mechanisms for these effects, which could exacerbate microcirculatory complications during cardiovascular diseases accompanied by increased Fg content. [source] Association of components of the metabolic syndrome with the appearance of aggregated red blood cells in the peripheral blood.DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 2 2005An unfavorable hemorheological finding Abstract Background Components of the metabolic syndrome are associated with low-grade inflammation. This can be accompanied by the synthesis of sticky proteins and erythrocyte aggregation. Methods The degree of erythrocyte aggregation was evaluated by a simple slide test and image analysis along with other markers of the acute-phase response, including the white blood cell count (WBCC), erythrocyte sedimentation rate (ESR), fibrinogen and high sensitivity C-reactive protein (hs-CRP) concentrations. Patients were categorized in four groups according to the absence or presence of 1, 2 and 3 or more components of the metabolic syndrome. Results We examined a total of 1447 individuals (576 women and 871 men) who gave their informed consent for participation. A significant cardiovascular risk factors, age and hemoglobin adjusted correlation was noted between the degree of erythrocyte aggregation and the number of components of the metabolic syndrome (r = 0.17, p < 0.0005). This correlation was better than that observed for clottable fibrinogen (r = 0.13 p < 0.0005), for ESR (r = 0.11 p < 0.0005) or WBCC (r = 0.13 p < 0.0005). A somewhat better correlation was noted for hs-CRP (r = 0.26 p < 0.0005). Conclusions The multiplicity of components of the metabolic syndrome is associated with enhanced erythrocyte aggregation, probably related to the presence of multiple adhesive macromolecules in the peripheral blood. The enhanced aggregation might contribute to capillary slow flow, tissue deoxygenation as well as vasomotor tone changes in the presence of multiple components of this syndrome. Copyright © 2004 John Wiley & Sons, Ltd. [source] Haemorheology in Gaucher diseaseEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2005Bridget E. Bax Abstract:, In Gaucher disease, a deficiency of glucocerebrosidase results in the accumulation of glucocerebroside within the lysosomes of the monocyte,macrophage system. Prior to the availability of enzyme replacement therapy (ERT), splenectomy was often indicated for hypersplenism. Haemorheological abnormalities could be expected in view of the anaemia and abnormal lipid metabolism in these patients and the role of the spleen in controlling erythrocyte quality. Objectives: To investigate the effect of Gaucher disease on blood and plasma viscosity, erythrocyte aggregation and erythrocyte deformability, and to determine whether observed rheological differences could be attributed to splenectomy. Methods: Haematological and haemorheological measurements were made on blood collected from 26 spleen-intact patients with Gaucher disease, 16 splenectomised patients with Gaucher disease, 6 otherwise healthy asplenic non-Gaucher disease subjects and 15 healthy controls. Results: No haemorheological differences could be demonstrated between spleen-intact patients with Gaucher disease and the control group. Compared to controls, both asplenic Gaucher disease and asplenic non-Gaucher disease study groups had a reduced MCHC (P = 0.003 and 0.005, respectively) and increased whole blood viscosity at 45% haematocrit (Hct), relative viscosity and red cell aggregation index , all measured at low shear (P < 0.05 for all). Additionally, asplenic patients with Gaucher disease alone showed an increased MCV (P = 0.006), an increased whole blood viscosity at 45% Hct measured at high shear (P = 0.019), and a reduced relative filtration rate (P = 0.0001), compared to controls. Conclusion: These observations demonstrate a direct and measurable haemorheological abnormality in Gaucher disease only revealed when there is no functioning spleen to control erythrocyte quality. [source] Increased strength of erythrocyte aggregates in blood of patients with inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 5 2009Nitsan Maharshak MD Abstract Background: Increased strength of red blood cell (RBC) aggregates are present during the acute inflammatory response and contribute to erythrocyte aggregation and may lead to microvascular dysfunction. Inflammatory bowel diseases (IBDs) are characterized by damage to the bowel wall. This damage may be at least partially attributed to microvascular ischemia caused by enhanced erythrocyte aggregation. The aim of this study was to evaluate the strength of RBC aggregates in the blood of patients with IBD. Methods: The strengths of RBC aggregates were characterized by integrative RBC aggregation parameters, determined by measuring of RBC aggregation as a function of shear stress. The results are represented as the area under the curve (AUC) of aggregate size plotted against shear stress. For each patient, dynamic aggregation and disaggregation of RBC were recorded and analyzed according to the RBC aggregate size distribution at the different shear stresses. Aggregation indices were correlated with disease activity and inflammatory biomarkers. Results: We examined 53 IBD patients and 63 controls. IBD patients had significantly elevated concentrations of inflammation-sensitive proteins and aggregation parameters. The strength of large aggregates, represented by AUC for large fraction aggregates, among patients (15.2 ± 18.6) was double that of controls (7 ± 10.9) (P = 0.006). The strength of large aggregates correlated with disease activity (r = 0.340; P < 0.001) with concentration of fibrinogen (r = 0.575; P < 0.001) and with concentration of high sensitivity C-reactive protein (r = 0.386; P < 0.001). Conclusions: The strength of RBC aggregates is increased in patients with IBD and correlates with the intensity of the acute phase response. This could contribute to bowel damage in these diseases. (Inflamm Bowel Dis 2009) [source] A Computer-Based Method for Determination of the Cell-Free Layer Width in MicrocirculationMICROCIRCULATION, Issue 3 2006SANGHO KIM ABSTRACT Objectives: The cell-free layer between the erythrocyte column and the vessel wall is an important determinant of hydrodynamic resistance in microcirculatory vessels. The authors report a method for continuous measurement of the width of this layer. Methods: The light intensity of a linear array of pixels perpendicular to the vessel axis is continuously determined from a video image of a microcirculatory vessel. A threshold level based on Otsu's method is used to establish the interface between the cell-free layer and the erythrocyte column. To test the method, video images at 750,4500 frames/s were obtained from venules and arterioles in rat spinotrapezius muscle at normal and reduced arterial pressures before and after induction of erythrocyte aggregation with Dextran 500. The current measurements were compared to manual measurements of the same images. Results: Values obtained by the manual and the new methods were in agreement within the 95% confidence limit by the Bland-Altman analysis and within 90,95% range by the correlation coefficient (R2). The more frequent measurements reveal substantial, rapid variations in cell-free layer width and changes in mean values with alteration of arterial pressure and red cell aggregability. Conclusions: A new, computer-based technique has been developed that provides measurements of rapid, time-dependent variations in the width of the cell-free layer in the microcirculation. [source] Correction of haemorheological disturbances in myocardial infarction by diquertin and ascorbic acidPHYTOTHERAPY RESEARCH, Issue 1 2003M. B. Plotnikov Abstract In a model of the high blood viscosity syndrome, developed after myocardial infarction in rats, it was observed that a therapy of a combination of diquertin (20,mg/kg) and ascorbic acid (50,mg/kg) for a period of 6 days, resulted in an improvement of haemorheological indices. The decrease in blood viscosity was primarily due to an improved deformability of erythrocytes, and to some extent, due to a decrease in the content of plasma fibrinogen and erythrocyte aggregation. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||