Clinical Hemorheology and Microcirculation - Volume 8, issue 3-4

Authors: Boisseau, M.R. | Copley, A.L.

Article Type: Editorial

DOI: 10.3233/CH-1988-83-401

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 281-282, 1988

Authors: Witte, Siegfried | Copley, Alfred L.

Article Type: Editorial

DOI: 10.3233/CH-1988-83-402

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 283-283, 1988

Authors: Boisseau, Michel R.

Article Type: Introduction

DOI: 10.3233/CH-1988-83-403

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 285-285, 1988

Authors: Schmid-Schönbein, H.

Article Type: Other

DOI: 10.3233/CH-1988-83-404

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 287-291, 1988

Authors: Stoltz, Jean François

Article Type: Other

DOI: 10.3233/CH-1988-83-405

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 293-303, 1988

Authors: Copley, A.L.

Article Type: Introduction

DOI: 10.3233/CH-1988-83-406

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 305-306, 1988

Authors: Chabanel, Anne

Article Type: Research Article

Abstract: The relationship between molecular structure and red blood cell (RBC) membrane viscoelasticity was investigated. To define the contribution of lipids to membrane viscoelasticity, we modified membrane cholesterol content and lipid fluidity. To determine the role of the protein skeleton on the cytoplasmic side of the membrane we used RBCs with a molecular defect of the spectrin molecule (type I hereditary elliptocytosis). Treatment of normal erythrocytes with N-ethyl-maleimide (NEM) resulted in RBCs with the same structural defect of the spectrin molecule. We compared the membrane viscoelasticity of these NEM-treated-RBCs to that of elliptocytes. To assess the role of the hemoglobin layer …associated with the membrane we studied the viscoelasticity of young and old RBCs. The membrane viscoelasticity was determined by the micropipette test. Membrane lipid fluidity was estimated by fluorescence depolarization. Results indicated that lipid composition and fluidity were not determinants of RBC membrane viscoelasticity. However our results showed that the viscoelastic properties of the RBC membrane are affected by a specific change in the state of membrane spectrin. The membrane mechanical behavior of old RBCs suggested that the hemoglobin associated with the membrane might influence the viscous response to membrane deformation. This work demonstrates that integrity and stability of the protein network are essential to the mechanical function, while modification of the lipid core does not affect membrane viscoelasticity. These findings are important when therapies are designed to improve RBC rheology in pathological conditions: the membrane skeleton should be the main target. Show more

Keywords: membrane viscoelasticity, micropipette test, cholesterol, membrane fluidity, hereditary elliptocytosis, density-separated red cells

DOI: 10.3233/CH-1988-83-407

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 307-320, 1988

Authors: Forconi, S.

Article Type: Research Article

Abstract: The correlation between blood hyperviscosity and ischemia is easy to understand if we consider that every condition in which viscosity increases causes a decrease in blood flow and, viceversa, every condition in which viscosity decreases induces an improvement in blood supply to tissues. This finding has been demonstrated “in vivo” in all the diseases where a primary blood abnormality provoked a reduction of blood fluidity. On the contrary there is clear evidence that in other conditions charachterized by reduction of vessel bore, due to obstructions or stenoses, blood fluidity may decrease as a consequence of tissue ischemia. The administration of …drugs capable of modifying vessel bore is followed by changes of blood viscosity (decrease after vasodilators and increase after vasoconstrictors). In patients where the vessel obstruction has been successfully removed with surgery, blood viscosity, previously increased, rapidly returned to normal level. These data confirm, in these pathophysiological conditions, the variability of blood fluidity and its dependence on primary vascular hemodynamic changes. Show more

Keywords: Blood Hyperviscosity Syndromes, Ischemia, Blood flow, Vascular Diseases

DOI: 10.3233/CH-1988-83-408

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 321-339, 1988

Authors: Heilmann, L.

Article Type: Research Article

Abstract: Interference with its oxygen supply is a major risk to the fetus during intrauterine life. Several important factors are concerned in maintaining the supply of oxygen to the fetus (maternal plasma volume expansion, dilated uterine arteries, low maternal hematocrit and viscosity and high cardiac output). All those factors govern the amount of oxygen reaching the fetus and disease processes of many kinds may interfere (pre-eclampsia, intrauterine growth retardation, Oligohydramnion). Garn et al. (1981), Sagen et al. (1984), and Murphy et al. (1986) demonstrated the potentically morbidigenic effect of high hematocrit and elevated red cell aggregation. The frequencies of perinatal death, …low birth weight and abnormalities of fetal heart rates were higher with hematocrit above 38% or/and red cell aggregation above 28 (-). By contrast, a decreasing hematocrit is associated with improved pregnancy- and fetal outcome. We have used plasma volume expansion therapy with hydroxyethylstarch 200/0.5, 10% in acute and chronic situations with fetal hypoxia. Plasma volume expansion leads to an increase in maternal and fetal cardiac output and improves the placental blood flow. We conclude that the presence of a high hematocrit and red cell aggregation should alert the obstetricans to the increased perinatal risk. Show more

Keywords: pregnancy, hemorheology, hypoxia, fetal outcome

DOI: 10.3233/CH-1988-83-409

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 341-350, 1988

Authors: Boccalon, Henri J.L.

Article Type: Introduction

DOI: 10.3233/CH-1988-83-410

Citation: Clinical Hemorheology and Microcirculation, vol. 8, no. 3-4, pp. 351-351, 1988