Biorheology - Volume 18, issue 3-6

Authors: Stoltz, J.F. | Lucius, M.

Article Type: Research Article

Abstract: From an analysis of the researches works published on blood viscoelasticity and thixotropy, the authors suggest applying the models used for polymer solutions, in order to account for the phenomena observed with blood (transient and periodic flow). The authors also examine the main techniques and devices for approaching blood viscoelastic and thixotropie properties and cell aggregation (rouleaux). The clinical and pharmacological applications which have been carried out are also summarized.

Keywords: hemorheology, viscoelasticity, thixotropy, aggregation of erythrocytes, rheological models, clinical measurements

DOI: 10.3233/BIR-1981-183-611

Citation: Biorheology, vol. 18, no. 3-6, pp. 453-473, 1981

Authors: Yepsen, G. | Boutin, D. | Litt, M. | Kron, R.E.

Article Type: Research Article

Abstract: A method of determining the non-Newtonian viscosity of fresh blood at a low shear rate consists of analyzing the transient pressure in a capillary flow system subjected to a step function input in the flow rate. The procedure requires solution of the first order step response equation for the flow of a suitable model fluid. A power law model has been used here. The model parameters were sensitive to such variables as hematocrit, presence of anticoagulants, and red cell deformability.

Keywords: fresh Blood Viscosity, Power Law, transient response

DOI: 10.3233/BIR-1981-183-612

Citation: Biorheology, vol. 18, no. 3-6, pp. 475-484, 1981

Authors: Brooks, Donald E. | Easthope, Peter L.

Article Type: Research Article

Abstract: An examination has been made of the variation through the menstrual cycle of blood viscosity and some of the parameters, including the concentrations of some acute phase reactants, which affect blood flow. Effects on blood viscosity were determined by fitting values of shear stress, T, derived from a Contraves LS-2 rheometer, as a function of shear rate, D, and haematocrit, H, to the empirical constitutive function T = X 1 exp ( X 2 H + X 4 / H 2 …) D 1 − X 3 H where X1 to X4 are the adjustable parameters which characterize the intrinsic flow behaviour of the sample. Fibrinogen, albumin, α 2macroglobulin, IgM and antithrobmin III levels in the plasma, whole blood clotting times and erythrocyte sedimentation rates were also measured. Based on over 70 rheological determinations on 12 women and over 200 protein concentration determinations on 43 women it was concluded that no cyclical changes occurred in either the rheological characteristics of anticoagulated blood or the other parameters measured. Show more

Keywords: Menstrual Cycle, Blood viscosity, Constitutive function

DOI: 10.3233/BIR-1981-183-613

Citation: Biorheology, vol. 18, no. 3-6, pp. 485-492, 1981

Authors: Rusch, Ph. | Herrmann, T. | Geyssant, A. | Vasselon, C. | Champailler, A. | Healy, J.C.

Article Type: Research Article

Abstract: Using a new automatic device and a standardised protocole for looking the filterability of erythrocytes through 5 μ pores, we introduced the IF (Index of Filterability) parameter. We demonstrate that IF is dependent on the viscoelastic properties of RBC membranes when Hb is normal, and dependent on Hb and O2 saturation of Hb when Hb is unstable (Thalassemia or drepanocytosis). The molecular interpretation and the interest of that for clinical screening or extensive studies are discussed.

Keywords: Red blood cells, Filterability, Oxygen tension, Hematocrit, Intracellular Enzymes

DOI: 10.3233/BIR-1981-183-614

Citation: Biorheology, vol. 18, no. 3-6, pp. 493-499, 1981

Authors: Quemada, D.

Article Type: Research Article

Abstract: RBC-RBC and RBC-protein interactions are known as strongly influencing the rheological behaviour of blood. As (i) at physiological level in hematocrit these effects are imbricated and (ii) most of previous methods required experimental conditions more or less distant from the physiological ones, further analysis of rheological effects of these interactions seems needed. A new attempt is presented, which grounds on viscosity data processing in terms of an “actual packing concentration” (APC), as a structural parameter. At given hematocrit H and shear rate γ ˙ , the APC is the packing concentration which would be obtained if …particles (aggregates or single ones) were packed without change in their actual state (i.e. the state they have at Hand γ ˙ values). Discussion of hematocrit dependence of low and high shear APCs in the cases of Whole Blood, Defibrinated Blood and Ringer Suspension of cells (from CHIEN et al’s viscosity data) allows one to postulate reasonable structural changes at critical hematocrits, noticely at a percolation like threshold. Relative importance of RBC aggregation and RBC deformation by crowding 1S then deduced. Show more

Keywords: Hemorheology, Structural parameters, RBC Aggregation, Hematocrit Dependence, Viscosity model

DOI: 10.3233/BIR-1981-183-615

Citation: Biorheology, vol. 18, no. 3-6, pp. 501-516, 1981

Authors: Corry, W.D. | Jackson, L.J. | Seaman, G.V.F.

Article Type: Research Article

Abstract: Low molecular weight hydroxyethyl starch (HES) was examined for its capacity to aggregate human erythrocytes (RBC) suspended in phosphate buffered saline (PBS). Preliminary studies showed that the effect of RES was dependent not only on the concentration of HES present but on the shear history of the sample as well. After a procedure for standardizing the shear history of the samples was established, measurements of the low shear viscosity, erythrocyte sedimentation rate (ESR) and zeta sedimentation ratio (ZSR) of the RBC-RES suspensions showed that RBC aggregation increased with HES concentration. This trend continued until an HES concentration of ∼ 4% …was reached. Further increases in HES concentration reduced the extent of RBC aggregation. Decreases in the extent of aggregation may have arisen from electrostatic repulsive forces which increase monotonically with RES concentration. Show more

Keywords: Aggregation, electrophoretic mobility, erythrocyte, hydroxyethyl starch, rheology, viscosity

DOI: 10.3233/BIR-1981-183-616

Citation: Biorheology, vol. 18, no. 3-6, pp. 517-529, 1981

Authors: Goldsmith, Harry L. | Lichtarge, Olivier | Tessier-Lavigne, Marc | Spain, Samira

Article Type: Research Article

Abstract: We describe a traveling microtube technique, previously applied to polystyrene latices (11), in which the trajectories of colliding microscopic spheres in Poiseuille flow may be photographed and analyzed with the aid of hydrodynamic theory to calculate the interaction forces due to electrostatic repulsion, van der Waals attraction or polymer bridging which occur when surfaces approach closer than 50 nm. The method was applied to human red cells of antigenic type A or B, sphered at constant volume or surface area, fixed with glutaraldehyde and suspended in aqueous glycerol with or without the addition of the corresponding antibody. The trajectories of …transient doublets of colliding sphered red cells exhibited marked asymmetry, not due to electrostatic repulsion but due to the presence of surface asperities on the particles. In the presence of antisera, permanent doublets formed due to bridging of antibody between antigenic sites on adjacent cell surfaces. Forces of the order of 0.1 nN were required to break up these linkages. Measurements of the period of rotation showed that permanent doublets behaved as rigid dumbbells except at the lowest antiserum concentration. Trajectories of colliding rabbit granulocytes were also studied and found to be markedly asymmetric due to the ruffled surfaces of the cells. Nevertheless, some collisions resulted in the formation of permanent doublets. Show more

Keywords: Trajectories, collisions, sphered red cells, granulocytes

DOI: 10.3233/BIR-1981-183-617

Citation: Biorheology, vol. 18, no. 3-6, pp. 531-555, 1981

Authors: Whitmore, Raymond L.

Article Type: Research Article

Abstract: Fresh human erythrocytes were resuspended in phosphate-buffered dextran solutions at osmolarities ranging from normal down to hemolysis in order to change their shape. Another batch of the erythrocytes was hardened and resuspended. From rheological measurement made in Brookfield and Contraves viscometers it was concluded that the rigidity of an erythrocyte was much more important than its shape in determining the bulk rheology of blood.

Keywords: Blood, Erythrocyte Volume, Erythrocytes, Rheology, Suspensions, Viscosity

DOI: 10.3233/BIR-1981-183-618

Citation: Biorheology, vol. 18, no. 3-6, pp. 557-562, 1981

Authors: Palade, G.F. | Simionescu, M. | Simionescu, N.

Article Type: Research Article

Abstract: The distribution of anionic sites on the luminal surface of the fenestrated endothelium of intestinal and pancreatic blood capillaries was investigated using cationized ferritin (CF), pI 8.4, as a probe. CF was administered in vivo by i.v. injection, or added to perfusates in in situ experiments. Anionic sites were found distributed in differentiated micro domains clearly associated with structural elements involved in capillary permeability. The affinity and intensity of CF labelling decreased in this order: 1- fenestral diaphragms, 2- coated pits and vesicles, 3- plasmalemma proper. Neither the membranes, nor the associated stomatal diaphragms of plasmalemmal vesicles and transendothelial channels …were labelled by CF. All anionic sites could be removed from the luminal surface of the endothelium by perfusion with protases of broad specificity (pronase, papain). The anionic sites of the fenestral diaphragms were preferentially removed by perfusion with heparinase, an indication that they are contributed by heparan sulfates. The implications of these findings are discussed in relation to capillary permeability to charged macromolecules, primarily plasma proteins. Show more

Keywords: Capillary Endothelium, Ionic Sites, Differentiated Microdomains, Heparan Sulphate, Fenestral Diaphragms, Plasmalemmal Vesicles

DOI: 10.3233/BIR-1981-183-619

Citation: Biorheology, vol. 18, no. 3-6, pp. 563-568, 1981

Authors: Winlove, C.P. | Davis, Jane | Iacovides, A. | Chabane1, Ann

Article Type: Research Article

Abstract: A tracer system suitable for radioisotope, autoradiographic or electron microscopic investigations of macromolecule transport in tissues is described. The tracer consists of an electron dense nucleus of radioactive colloidal gold stabilised by a macromolecular coating into which a second radioactive label may be incorporated. The physical characteristics of the tracer system have been investigated. Commercially produced gelatin coated particles suspended in 0.9% NaCl had total hydrodynamic radii ranging between 70 Å and 200 Å and nuclear radii of between 15 and 25 Å. Particles of a single hydrodynamic radius showed similar electrophoretic mobility but had a wide range of iso- electric points. …Incubation in plasma produced an increase in the hydrodynamic radius of the particles. The rate of adsorption increased with the initial radius of the particles and with the temperature of incubation. From the temperature dependence an activation energy for the adsorption process of 46 ± 6 k Joule mole−1 was deduced. Incubation with serum or with fibronectin produced a smaller increase in particle size, but incubation with fibrinogen, albumin or γ -globulin, alone or in combination in either 0.9% NaCl or Tyrode’s solution, had no effect on particle size. Show more

Keywords: Macromolecule transport, Protein adsorption, Gold colloid

DOI: 10.3233/BIR-1981-183-620

Citation: Biorheology, vol. 18, no. 3-6, pp. 569-578, 1981