Biorheology - Volume 8, issue 1

Authors: Sirs, John A.

Article Type: Research Article

Abstract: Measurements have been made of the relative changes of the flexibility and respiratory function of erythrocytes after adding aldosterone (10–5000 μ g/l.) to blood and cell suspensions. With whole blood no difference was observed. With washed cells or blood diluted many-fold in Ringer-Locke solution aldosterone significantly reduced these factors. Washing cells on its own produces a degree of inflexibility of the erythrocytes and the aldosterone effect is superimposed on this. Re-adding plasma to the washed cells reverses the inflexibility and prevents the aldosterone interaction. A similar decrease of flexibility and lowering of respiratory efficiency has been observed with patients having …Conn’s Syndrome. After treatment with aldactone, or surgical removal of the adrenal glands, these factors are significantly improved and nearer normal. Show more

DOI: 10.3233/BIR-1971-8101

Citation: Biorheology, vol. 8, no. 1, pp. 1-10, 1971

Authors: Stoltz, J.F. | Vigneron, C. | Streiff, F. | Larcan, A.

Article Type: Research Article

Abstract: Les auteurs font une revue générale des principaux travaux publiés concernant le problème de la rhéologie de l’hématie. Ils soulignent en particulier l’impossibilité de considérer l’hématie comme une particule solide et montrent l’importance de l’introduction de la notion de “viscosité interne”. Du point de vue microscopique, après avoir rappelé les principales techniques d’études des propriétés mécaniques du globule rouge, ils rappellent que certaines de celles-ci sont susceptibles de permettre de proposer des modèles rhéologiques globaux pour le comportement de la membrane érythrocytaire. Entin, il semble que la forme particulière de l’hématie soit due à une minimisation de l’énergie superficielle.

DOI: 10.3233/BIR-1971-8102

Citation: Biorheology, vol. 8, no. 1, pp. 11-22, 1971

Authors: Champion, J.V. | North, P.F. | Coakley, W.T. | Williams, A.R.

Article Type: Research Article

Abstract: Shear breakage of human blood cells in saline solution has been studied under conditions of uniform shear, non-penetrating thickeners having been added merely to facilitate application of a sufficiently high stress using a conventional cone and plate apparatus. Cells in isotonic saline fragment and many micro spheres are formed. In hypotonic saline, haemolysis replaces fragmentation; few microspheres result. A shear stress threshold exists for haemolysis. The shear stress required to produce 50% haemolysis depends on the type of thickening additive; values of 2200 and 10,000 dyne cm−2 are obtained for cells in Dextran and Methocel, respectively. Both microsphere formation …and degree of haemolysis depend on the applied shear stress and the time of shearing. Show more

DOI: 10.3233/BIR-1971-8103

Citation: Biorheology, vol. 8, no. 1, pp. 23-29, 1971

Authors: Matchett, R.H. | Scott Blair, G.W.

Article Type: Letter

DOI: 10.3233/BIR-1971-8104

Citation: Biorheology, vol. 8, no. 1, pp. 31-32, 1971

Authors: Copley, A.L. | Scott Blair, G.W.

Article Type: Introduction

DOI: 10.3233/BIR-1971-8105

Citation: Biorheology, vol. 8, no. 1, pp. 33-33, 1971

Authors: Chien, Shu | Usami, Shunichi | Dellenback, Robert J. | Bryant, Cyrus A.

Article Type: Research Article

Abstract: The rheological behavior of blood and red cell suspensions was studied in five mammalian (man, dog, elephant, sheep and goat) and four non-mammalian (turkey, box turtle, frog and amphiuma) species. Normal red cells from these species were suspended in Ringer solution, serum, plasma and fibrinogen solutions; aldehyde-hardened red cells were suspended in Ringer solution. Viscosity measurements were made at different temperatures and over wide ranges of shear rates and cell volume concentrations, and the findings were correlated with the data on cell passage through micropores in polycarbonate sieves and on centrifugal packing. Analyses of the results indicate that the shape …(axial asymmetry or deviation from sphericity) of the suspended cells or aggregates exerts a greater influence than their size on the rheological behavior of blood. The cell shape can be changed by two shear-dependent phenomena: cell deformation and cell aggregation. Cell deformability is determined by membrane flexibility (area-to-volume ratio and tensile property of membrane) and the internal viscosity (physico-chemical state of internal fluid and MCHC). Cell aggregation depends on the aggregation tendency of RBC (deformability, etc.) and the aggregating effectiveness of plasma proteins (fibrinogen and α 1 - and β 2 -globulins). The shape change due to cell deformation and cell aggregation, together with the true cell volume concentration determine the effective cell volume concentration, which in turn is the final determinant of blood viscosity. Based upon the knowledge gained from such comparative studies, a systematic approach to analyze the hemorheological abnormalities in various hematological diseases has been proposed. Such studies promise to improve our understanding of the pathogenesis and the methods of management in these disorders. Show more

DOI: 10.3233/BIR-1971-8106

Citation: Biorheology, vol. 8, no. 1, pp. 35-57, 1971

Authors: Guest, M. Mason | Derrick, John R. | Bond, Ted P.

Article Type: Research Article

Abstract: High-speed cinematography was used to study the behavior of erythrocytes in the microcirculation of the human omentum and the canine mesentery. Normal human erythrocytes in the microcirculation of the human omentum and normal human or canine erythrocytes in the microcirculation of the canine mesentery exhibited remarkable flexibility. In capillaries the erythrocytes assumed a hollow paraboloid shape and, in larger vessels, reversible bending of the cells was frequently observed. In contrast, erythrocytes in the microcirculation of the omentum in patients with acquired hemolytic anemias were unaltered in shape when traversing capillaries. The cells in all observed vessels appeared as rigid, biconcave, …distorted disks. Human, canine or sheep erythrocytes, after treatment with glutaraldehyde or formalin and tannic acid, when infused into the microcirculation of the canine mesentery, retained their biconcave shape while traversing capillaries. The rigidity of erythrocytes in some types of hemolytic anemia may be responsible for their shortened life span, either because of increased trauma to the cells as they travel through the systemic circulation or because of splenic trapping. Show more

DOI: 10.3233/BIR-1971-8107

Citation: Biorheology, vol. 8, no. 1, pp. 59-64, 1971