Clinical Hemorheology and Microcirculation - Volume 14, issue 2

Authors: Witte, Siegfried | Stoltz, Jean-François

Article Type: Other

DOI: 10.3233/CH-1994-14201

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 147-148, 1994

Authors: Jones, J.G. | Adams, R.A. | Evans, S.-A.

Article Type: Review Article

Abstract: The flow rate of suspensions of blood cells through micropore filters is widely used for assessing the deformability of red and white blood cells. Mathematical models have been described as a theoretical basis for the technique. There is conflicting data concerning the filterability of red cells in a number of disorders. Part of the confusion stems from the use of different models for various experimental systems and results being expressed in a variety of ways. Confusion also arises from the use of models, derived for studying red blood cells, for the analysis of mixed populations of blood cells e.g. blood …filterability being equated with red blood cell deformability. Successful attempts to analyse the flow of heterogeneous populations of blood cells require the use of complex models which seem too daunting for routine clinical use. The current trend is to isolate cells and, as far as possible, work with a homogeneous preparation with allowance for a small degree of permanent pore occlusion. From the known properties of isolated cells, it is apparent that the analysis of the filtration of unfractionated blood cells can be reduced to a series of three relatively simple analyses of this type. The time may therefore be right to return to blood filtration for investigating the filterability of blood cells in clinical disorders of suspected microcirculatory flow. Show more

Keywords: Filterability, Erythrocyte, Leukocyte, Monocyte, Blood

DOI: 10.3233/CH-1994-14202

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 149-169, 1994

Authors: Boisseau, M.R. | Mazoyer, E. | Ripoll, L. | Drouet, L.

Article Type: Review Article

Abstract: Epidemiological studies have demonstrated that plasma fibrinogen (Fg) level in the superior quartils is predictif of an increased risk of cardiovascular thrombotic events. Many clinical studies have evaluated the clinical efficiency of ticlopidine in vascular pathology and in several of them, plasma Fg levels have been determined. We analyzed all reported data to evaluate the effect of ticlopidine on plasma Fg levels. These studies are heterogeneous: plasma Fg concentration was measured using various methods; patients were included at various time after the acute event and were followed over a period of 1 to 24 months of treatment with ticlopidine; patients …suffered from peripheral arterial disease and/or cerebrovascular disease and/or diabetes and/or polycythemia vera. Despite the heterogeneity of these prospective studies, a general trend indicates a decrease in the plasma Fg levels by 10 to 25% during the first 3 months of therapy with ticlopidine compared to placebo. This decrease in circulating Fg was, when studied, associated with clinical improvement and hemorheological modifications (decreases in whole blood and plasma viscosities). However, no definitive conclusion can be drawn concerning the effect of ticlopidine on plasma Fg levels and, if this effect exists, does it participate to the clinical benefit of the treatment together with its antithrombotic effect? Show more

Keywords: Fibrinogen, Ticlopidine, Cardiovascular Disease, Risk Factors

DOI: 10.3233/CH-1994-14203

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 171-180, 1994

Authors: Lechner, P. | Walzl, M. | Walzl, B.

Article Type: Research Article

Abstract: Fibrinogen and lipoproteins are considered to be the most decisive pacemakers in the pathogenesis of atherosclerosis. H.E.L.P. is based on the fact that lipoproteins as well as fibrinogen are precipitated at acid pH-values in the presence of heparin. Their elimination therefore leads to restoration of the micro-circulation, while the haemostasiological pattern remains unchanged. The increased oxygen supply to the tissue enables us to perform limb-saving surgical procedures instead of mutilating amputations: 16 patients with peripheral arterial disease in Fountaine's stages III and IV were submitted to 15 H.E.L.P. treatments each instead of primary limb amputation. Surgery was limited to the …removal of gangrenous tissue only. None of the patients experienced any side-effects due to the procedure. Show more

Keywords: Plasmapheresis, H.E.L.P., fibrinogen, atherosclerosis, peripheral arterial disease

DOI: 10.3233/CH-1994-14204

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 181-188, 1994

Authors: Jung, F. | Koscielny, J. | Mrowietz, C. | Pindur, G. | Förster, H. | Schimetta, W. | Kiesewetter, H. | Wenzel, E.

Article Type: Research Article

Abstract: In a single blind randomized cross-over study 6 volunteers each received infusions of 500 ml of 6 different types of hydroxyethyl starch (HES) solutions. Between the test periods there was a regular wash-out phase of 3 months. The concentration and molecular weight distribution of the intravascular HES-molecules as well as the blood fluidity were determined before and up to 24 hours after the infusions. The C2/C6 substitution ratio and the molar substitution exert an essential influence on the elimination of the HES-molecules. An increase in the C2/C6 substitution ratio from 4.6 to 10.8 with unchanged molecular weight (MW) and …molar substitution brings about an increase in the half-life of the elimination in the β-phase t1/2-β from 10.4 to 19.5 hours. In case a high C2/C6 substitution ratio is combined with a high molar substitution (0.62 instead of 0.5), half-life rises up to 36.1 hours. Whereas the molecular weights of all medium-molecular HES-types (MW 200,000) decrease, the medium molecular weight of the low-molecular HES-type (MW 40,000) rises up to 102±9 kDalton after 24 hours. The HES-type with a molar substitution of 0.5 attain a molecular weight ranging between 72±2 and 108±4 kDalton after 24 hours. High-substituted HES (molar substitution of 0.62) in combination with a high substitution ratio showed a MW of 136±8 kDalton and, as such, considerably bigger degradation products. After the infusion of all HES solutions there is a decrease in haematocrit levels which is most strongly marked with high-substituted HES in combination with a high C2/C6 substitution ratio. Only the solutions with a high C2/C6 substitution ratio produce an increase in plasma viscosity. Show more

Keywords: haemodilution, hydroxyethyl starch, blood fluidity, elimination kinetics

DOI: 10.3233/CH-1994-14205

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 189-202, 1994

Authors: Tozzi, E. | Tozzi-Ciancarelli, M.G. | Di Massimo, C. | Mascioli, A. | Gentile, T. | de Matteis, F.

Article Type: Research Article

Abstract: Hemorheological parameters were analyzed on 50 simple type obese children after 12 months of an adequate diet and physical training. According to the changes of body weight, the subjects were divided into three groups. The hyperviscosity condition disappeared in obese children with a real weight loss, while it remained in the groups of subjects with persistent overweight and with increased weight. A decrease of erythrocyte membrane lipid peroxidation, expressed as malondialdehyde (MDA) , was observed only in the children with a real weight loss, suggesting that the persistent trend toward lipid peroxidation may be considered a significant risk factor for …atherosclerosis. Show more

Keywords: atherosclerosis, obesity, hemorheological parameters, lipid peroxidation, weight loss

DOI: 10.3233/CH-1994-14206

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 203-211, 1994

Authors: Luquita, A. | Dominighini, A. | Rasia, R. | Rasia, M.

Article Type: Research Article

Abstract: Chronic renal failure (CRF) is a heterogeneous disease of variable etiology and development, commonly associated with other pathologies. Therefore, studies of human red cell rheological alterations caused by CRF show different and controversial results. In order to avoid additional factors influencing blood rheology in CRF an experimental model was used. Ten inbred rats underwent surgical CRF and erythrocyte rheology (globular deformability, elastic modulus, and surface viscosity) during syndrome evolution and to biochemical parameters marking renal failure (serum creatinine, serum urea) were studied. The results obtained indicate that the syndrome reaches its greatest severity a week after surgical ablation has been …completed, then declining to an level intermediate between the maximum and normal. Erythrocyte mechanical behavior follows a similar pattern, but with improvement beginning in the second week and evolving until it surpasses the normal values. Show more

Keywords: Erythrocyte rheology, chronic renal failure

DOI: 10.3233/CH-1994-14207

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 213-221, 1994

Authors: Mukherjee, Manjari | Desai, Amita P.

Article Type: Research Article

Abstract: The concentration of 5'-adenosine diphosphate (ADP) required to produce fifty percent of the estimated maximal response (ADP EC50 ) was determined by computerised probit analysis. This correlated directly and significantly with the minimum concentration of ADP required to produce (i) a biphasic aggregation response (ADPBiphasic ); and (ii) a maximal aggregation response exceeding 50% (ADPPA > 50 ). Platelet aggregability was evaluated in 70 subjects consisting of 18 patients with coronary heart disease (CHD), 13 with ischemic cerebrovascular disease (CVD), 18 with rheumatoid arthritis (RA) and in 21 healthy controls. The mean (SEM) values of EC50 were slightly but …not significantly decreased (hence platelet aggregability increased) in patients with CHD (2.58 +− 0.36 μmoles/L) and RA (2.23 +− 0.36 μmoles/L) as compared with controls (2.94 +− 0.34 μmoles/L); and slightly elevated in patients with ischemic CVD (3.39 +− 0.34 μmoles/L). The mode values of ADPPA > 50 were also less in the CHD and RA groups (2 μmoles/L) as compared with the controls (4 μmoles/L); in the CVD group the mode was 4 μmoles/L. The mode values of ADPBiphasic were however the same in all the four groups, namely 2 μmoles/L. Show more

Keywords: Probit analysis, platelet aggregation

DOI: 10.3233/CH-1994-14208

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 223-231, 1994

Authors: Ruef, Peter | Zilow, Eugen P. | Linderkamp, Otwin

Article Type: Research Article

Abstract: Volume and deformability of peripheral immature (bands and metamyelocytes) and mature polymorphonuclear neutrophils (PMN) were studied in venous blood of healthy neonates, children and adults. Metamyelocytes were found only in neonatal blood. Membrane cytoplasm tongues of PMN were aspirated into 2.5-μm (diameter) micropipettes over a period of 1 min. Compared with mature PMN, final tongue lengths of band cells were decreased by 44 to 50% and volumes were increased by 14 to 17%. Neonatal metamyelocytes were more rigid and larger than neonatal band cells. Among mature PMN and band cells in the neonates, children and adults cellular volume and deformation …behavior were similar. We conclude that immature neutrophils are markedly less deformable than mature PMN and that these cells may contribute to impaired microcirculation in patients with a marked rise of immature neutrophils in peripheral blood. Show more

Keywords: Asphyxia, immature neutrophils, leukocyte deformability, neonates

DOI: 10.3233/CH-1994-14209

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 233-236, 1994

Authors: Wang, X. | Stoltz, J.F.

Article Type: Research Article

Abstract: On the basis of experimental viscometric determinations with human blood, the authors used a SISKO type relationship to describe the non-Newtonian rheological behaviour of blood : τ = ηp (η$\dot{\gamma}$ + α$\dot{\gamma}$ 1/2 ) where ηp is the plasma viscosity; η is a non-dimensional parameter equal to the relative viscosity of blood at infinite shear rate and α a constant characterizing the structure of blood. A good concordance was observed between the experimental blood viscosity and the theoretical values given by the relationship both for normal blood (n=133) and pathological samples (n=157). The model parameters …were stable and well correlated with hematocrit and with RBC aggregation time measured by a laser back-scattering method. We tried equally to characterize pathological bloods by the model parameters. The statistic analysis showed that the mean values of α and η for some pathological samples (Kahler's disease, Waldenström's disease, Hypertension) were significantly different from normal values. It will be interesting to extend this study to other diseases, in particular to bloods in which the blood cells present altered rheological properties. Show more

Keywords: blood viscosity, rheological relationship, clinical applications, RBC aggregation

DOI: 10.3233/CH-1994-14210

Citation: Clinical Hemorheology and Microcirculation, vol. 14, no. 2, pp. 237-244, 1994