Measurement Of Erythrocyte Deformability Research Articles

Measurement of Erythrocyte Deformability by Automated Image Analysis

We describe here a new method of measuring quantitative parameters of erythrocyte deformability by automated analysis of images obtained using an erythrocyte deformation device, allowing fixation with glutaraldehyde directly within the shear flow. The method for measuring erythrocyte deformability includes capture of images from the device for erythrocyte deformation in shear flow and automatic image analysis, including preprocessing, binarization, identification of objects on images, and counting of the numbers of objects by approximating the objects of interest to ellipses. Processing yielded a coefficient of deformability for each erythrocyte, along with statistical indicators: the distribution function, mean deformability, dispersion, and the coefficient of asymmetry. This method provides assessment of the distribution of erythrocytes by deformability and, thus, additional diagnostic and scientific information; the accuracy of assessments of erythrocyte deformability is increased.

Measurement of erythrocyte deformability by radial spreading rheometry

Measurement of erythrocyte deformability by radial spreading rheometry

Preparation of standards for quality control of the measurement of erythrocyte deformability (filterability)

Preparation of standards for quality control of the measurement of erythrocyte deformability (filterability)

Measurement of erythrocyte deformability by cell transit analyser

Erythrocyte deformability (filterability) as measured by the Cell Transit Analyser was studied in the presence and absence of contaminating leucocytes and platelets. The effects of two anticoagulants (lithium heparin and K 2 EDTA), no anticoagulant (defibrinated blood) and two buffers (HEPES and phosphate) were also evaluated

Comparison of instruments for measurement of erythrocyte deformability

Comparison of instruments for measurement of erythrocyte deformability

Measurement of erythrocyte deformability by uniaxial stretching -Influence on apparent Young's modulus and time constant by inner viscosity-

Measurement of erythrocyte deformability by uniaxial stretching -Influence on apparent Young's modulus and time constant by inner viscosity-

Measurement of Erythrocyte Deformability by Uniaxial Stretching

Measurement of Erythrocyte Deformability by Uniaxial Stretching

Measurement of Erythrocyte Deformability by Viscometry

Measurement of Erythrocyte Deformability by Viscometry

Allopurinol Prevents Erythrocyte Deformability Impairing but Not the Hematological Alterations After Limb Ischemia–Reperfusion in Rats

The measurement of red blood cell deformability provides a possible method for detecting the effect of ischemia–reperfusion on erythrocytes. In our study the effect of 1-h ischemia–reperfusion with or without allopurinol pretreatment on hematological parameters and red blood cell deformability was investigated in a follow-up experiment of 26 male CD outbred rats that were subjected to unilateral hind-limb ischemia by microvascular clips on femoral vessels for 1 h (IR, n = 6), some rats received allopurinol pretreatment under the same conditions (50 mg/kg, AP + IR, n = 8), others were subjected to sham operation (n = 6), and the rest of animals served as control (n = 6). Measurement of erythrocyte deformability using a bulk filtrometer with special setting of cell suspension hematocrit (1%), and determination of hematological parameters were performed daily for one week. In the IR group, relative cell transit time increased significantly on postoperative days 1 and 2, which was not observed in the other groups. Settings for the measurement of erythrocyte deformability by reducing the blood sample volume gave the possibility of monitoring the resulting changes in rats. Mean corpuscular volume and hemoglobin, platelet count, and platelet volume were higher in the IR and AP + IR groups than in the other groups. In summary, short-term ischemia and reperfusion induced lower red blood cell deformability in the early postoperative period, which could be prevented by allopurinol pretreatment.

Measurement of erythrocyte deformability and methodological adaptation for small‐animal microsurgical models

Measuring erythrocyte deformability with bulk filtrometers is common, but there are problems with standardization and sample quantity in small laboratory animals. In this study, blood was drawn from mice, rats, and dogs, and then erythrocyte suspensions at 1-5% hematocrit were prepared. Bulk filtrometers with a 5- or 3-microm pore-diameter filter were used to determine the initial relative filtration rate (IRFR) and relative cell transit time (RCTT). Hematological composition was also tested. In all species, the highest IRFR values occurred at 1% hematocrit, and the lowest values at 5%. In mice and rats, RCTT values were lowest at 1% and highest at 5% using a 5-microm filter, whereas in dogs, RCTT was elevated at 1-2%. Using a 3-microm filter, each species showed the same phenomena under 3%. RCTT values may become distorted above a certain cell-size/pore-size ratio. In mice and rats, 1% suspension is applicable for bulk filtrometry, but only using 5-microm filters.

Changes in erythrocyte deformability after liver resection for hepatocellular carcinoma associated with chronic liver disease.

Erythrocyte deformability is an important factor in the microcirculation. The deformability in patients with chronic liver disease is less than normal. We studied changes in erythrocyte deformability in 32 patients undergoing liver resection for hepatocellular carcinoma with underlying chronic liver disease to investigate whether the measurement of deformability gives information useful for postoperative management. We measured erythrocyte deformability as erythrocyte transit time (ETT) before and after resection, as well as the erythrocyte adenosine triphosphate level, mean corpuscular volume, mean corpuscular hemoglobin concentration, and indices of liver function. The 15-minute indocyanine green retention rate (ICGR15) was measured before resection. Correlations between the change in deformability and these values were evaluated, as was correlation with the scale of the operation and with the occurrence of postoperative complications. Mean ETT was higher in the patients before resection than in healthy volunteers. ETT was correlated with serum high density lipoprotein-cholesterol (p < 0.05). The incidence of postoperative complications was higher (p = 0.001) in the patients (group A) with ETT increased during the first 3 postoperative days by >/=1 SD of the mean of the preoperative value than in patients (group B) with less change. Of the 12 patients whose ICGR15 value was >/=20%, all 9 patients in group A had postoperative complications. The increase in ETT (decrease in erythrocyte deformability) is associated with the development of postoperative complications. The measurement of erythrocyte deformability gives information useful for postoperative management, and special monitoring for postoperative complications is necessary in patients with the increase soon after liver resection.

Measurement of erythrocyte deformability using a stroboscopic recording centrifuge

A stroboscopic recording centrifuge technique is described which can measure deformability of red blood cells in terms of the rate of packing at low g. It can be used to measure several whole blood samples simultaneously, with accurate control of the speed of rotation and recording time. Only 0.05 ml of blood is required per measurement, and no prior treatment or preparation of the sample is necessary. The calibration procedures to allow for variations of the haematocrit and plasma fibrinogen level are explained.

EKYTHROCYTE FILTERABILITY IN NORMAL PREGNANCY AND PRE‐ECLAMPSIA

British Journal of HaematologyVolume 53, Issue 2 p. 353-355 Free Access EKYTHROCYTE FILTERABILITY IN NORMAL PREGNANCY AND PRE-ECLAMPSIA John Stuart, John Stuart Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this authorM.W. Kenny, M.W. Kenny Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this authorT. C. M. Inglis, T. C. M. Inglis Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this author John Stuart, John Stuart Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this authorM.W. Kenny, M.W. Kenny Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this authorT. C. M. Inglis, T. C. M. Inglis Department of Haematology, Medical School, University of Birmingham, Birmingham B1 5 2TJSearch for more papers by this author First published: February 1983 https://doi.org/10.1111/j.1365-2141.1983.00337.x-i1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat REFERENCES Alderman, M.J., Ridge, A., Morley, A.A., Ryall, K.G. & Walsh, J.A. (1981) Effect of total leucocyte count on whole blood filterability in patients with peripheral vascular disease. Journal of Clinical Pathology, 34, 163 – 166. Buchan, P.C. (1980) Evaluation and modification of whole blood filtration in the measurement of erythrocyte deformability in pregnancy and the newborn. British Journal ol Haematology, 45, 97 – 105. Drummond, M.M., Lowe, G.D.O., Belch, J.J.F., Barbenel, J.C. & Forbks, C.D. (1980) An assessment of red cell deformability using a simple filtration method. Journal of Clinical Pathology. 33, 373 – 376. Gresele, P., Guerciolini, R. & Nenci, G.G. (1982) Erythrocyte deformability changes in normal pregnancy and pre-eclampsia. British Journal of Haematology. 52, 340 – 342. Inglis, T.C.M., Stuart, J., George, A.J. & Davies, A.J. (1982) Haemostatic and rheological changes in normal pregnancy and pre-eclampsia. British journnl of Haematology, 50, 461 – 465. Reid, H.L., Barnes, A.J., Lock, P.J., Dormandy, J.A. & Dormandy, T.L. (1976) A simple method for measuring erythrocyte deformability. Journal of Clinical Pathology. 29, 855 – 858. Stuart, J., Kenny, M.W., Aukland, A., George, A.J., Neumann, V., Shapiro, L.M. & Cove, D.H. (1983) Filtration of washed erythrocytes in atherosclerosis and diabetes mellitus. Clinical Hemorheology, in press. Volume53, Issue2February 1983Pages 353-355 ReferencesRelatedInformation

Evaluation and modification of whole blood filtration in the measurement of erythrocyte deformability in pregnancy and the newborn.

This study was designed to investigate the deformability of erythrocytes from pregnant women and full-term newborn infants, with healthy female adults as a comparison, using a whole blood filtration method. Delay in measurement, white cells, haematocrit, plasma viscosity, temperature and pH all significantly affected the rate of whole blood filtration and could thereby obscure or exaggerate changes in erythrocyte deformability. A new method was developed which eliminated or minimized these sources of error and the study was completed. Fetal erythrocytes were found to be significantly less deformable than adult erythrocytes which were in turn found to be significantly less deformable than erythrocytes from pregnant women. These differences appear to be related to the varying plasma fibrinogen concentrations in the three groups of subjects. The significance of these findings in the special haemodynamic situations found in the neonate and during pregnancy are discussed.

Influence of pentoxifylline on erythrocyte deformability in peripheral occlusive arterial disease.

Impaired red cell deformability has been found in patients suffering from chronic peripheral vascular disorders, the implication being that microcirculatory blood flow is hindered and tissue hypoxaemia is aggravated. Measurement of erythrocyte deformability by a standard filtration technique for whole blood was carried out in 40 young healthy persons, in 25 untreated patients with peripheral occlusive arterial disease and in 25 patients with matching vascular disease, before and after a 6-weeks' oral treatment with 400 mg pentoxifylline 4-times daily. The filtration rates were significantly lower in the patient groups compared to those of healthy volunteers. After the oral administration of pentoxifylline, a significant increase in filtration rates was observed pointing to an improvement in erythrocyte deformability. The findings suggest that by improving erythrocyte deformability pentoxifylline positively influences the microcirculatory blood fluidity, an important factor for efficient therapy in peripheral arterial occlusive disease.

Shear-dependent deformation of erythrocytes in rheology of human blood.

Shear-dependent deformation of erythrocytes in rheology of human blood.