Clinical Hemorheology and Microcirculation - Volume 30, issue 3-4

Authors: Bolokadze, N. | Varazashvili, M. | Salia, N. | Momtselidze, N. | Solomonia, R. | Mchedlishvili, G.

Article Type: Research Article

Abstract: The aim of the present study was investigation of the lipid peroxidation changes within the erythrocytes under conditions of increased RBC aggregation. This latter was produced both in the in vitro and in vivo conditions by the addition of Dextran T‐500. For the in vitro studies blood samples were taken from the cubital veins of 15 healthy subjects. During the in vivo studies 10 ml of the 10 per cent Dextran T‐500 solution was administered intravenously in six chinchilla rabbits. Another six animals were treated with rheopolyglucyne. The RBC aggregation in blood was investigated with the “Georgian technique”. The malondialdehyde …(the end product of lipid peroxidation) was determined in all cases by its reaction with thiobarbituric acid. We found that in the in vitro conditions, as well as in the in vivo studies, the lipid peroxidation was significantly increased in the erythrocytes during the enhanced RBC aggregation induced by addition of Dextran T‐500. Therefore we suppose that the elevated RBC aggregation cause an increase of cell's lipid peroxidation and it is possible to think that appropriate prooxidant: antioxidant balance is shifted toward the pro‐oxidants in the erythrocytes. Show more

Keywords: RBC aggregation, lipid peroxidation, in vitro studies, in vivo studies, Dextran T‐500

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 453-455, 2004

Authors: Pargalava, Nugzar | Mantskava, Maya | Mchedlishvili, George

Article Type: Research Article

Abstract: We investigated the RBC aggregability in the patients with the foot diabetic gangrenes: in the venous blood samples taken from the damaged foot before its amputation, as well as from the cubital vein (the systemic circulation). The RBC aggregability was investigated with the “Georgian technique” that is sensitive and provided us with direct and quantitative data. We found that the RBC aggregability was higher by about 20%, in the blood flowing from the gangrenous tissue than in the systemic circulation. Therefore, the sources of the systemic hemorheological disorders were the primarily damaged tissues. Taking into account that the blood is …uninterruptedly flowing and mixing together in the whole circulatory bed we conclude that in the systemic circulation a certain compensatory mechanism provide for a partial normalization of the blood rheological properties, since the RBC aggregability never reaches the level in the blood of the healthy people. Show more

Keywords: Microvascular hemorheology, diabetic gangrene, RBC aggregation

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 457-459, 2004

Authors: Sordia, T. | Tatarishvili, J. | Varazashvili, M. | Mchedlishvili, G.

Article Type: Research Article

Abstract: We analysed hemorheological disorders in the microcirculation of intestinal mesenterium of adult laboratory rats following massive exsanguinations when the mean arterial pressure dropped and then the hemorrhagic shock developed in the animals. The mesenteric microcirculation was analysed by the Texture Analysis System (Leitz, Wetzlar): (a) diameters of the afferent arterioles, capillaries, and efferent venules; (b) the blood flow velocity; (c) microvascular blood flow changes (during the RBC aggregation); (d) local microvascular hematocrit; and (e) the transformation of capillaries into plasmatic microvessels. During development of the hemorrhagic shock we found that the blood flow velocity decreased in all microvessels, there …was an increased RBC aggregation which gradually enhanced in the mesenteric microvessels' lumen causing blood flow slowing down till appearance of stases. A part of the capillaries transformed into plasmatic vessels. Therefore the microcirculation demonstrated a significant decrease, this being related both to the lowered pressure gradient and to specific hemorheological disorders in the capillary networks. Show more

Keywords: Hemorheological disorders, microcirculation, hemorrhage

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 461-462, 2004

Authors: Piagnerelli, M. | Zouaoui Boudjeltia, K. | Piro, P. | Brohee, D. | Vanhaeverbeek, M. | Vincent, J.L.

Article Type: Research Article

Abstract: Several recent in vitro studies have observed that alterations in red blood cell (RBC) rheology depend on sample temperature. This possibility could limit the in vivo validity of the assessment of RBC shape. We investigated the effects of sample temperature on RBC shape estimated by flow cytometry in septic patients compared with those of volunteers. 0.5 ml of blood was placed at 4°C, room temperature (20°C) or at 37°C. RBCs were analyzed at 30 minutes (T30) by flow cytometry and results compared to baseline measures. With the flow cytometry technique, the RBC shape of healthy volunteers shows a bimodal distribution …related to the biconcave form. On this histogram, we calculated the second Pearson coefficient of dissymmetry – PCD – representing the asymmetry of this histogram. At baseline, RBC PCD was increased in septic patients representing a more spherical shape compared to volunteers (−0.73±0.18 versus −0.95±0.05; p=0.007). For both groups, RBC shape estimated by the flow cytometry technique was not modified by the temperature of the sample. We conclude that estimation of RBC shape by flow cytometry is not influenced by the temperature of the sample. The present study validates the flow cytometry technique to assess RBC shape in vitro. Show more

Keywords: Red blood cell, flow cytometry, shape, temperature, sepsis

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 463-466, 2004

Authors: Shin, Sehyun | Ku, Yunhee | Park, Myung‐Su | Suh, Jang‐Soo

Article Type: Research Article

Abstract: A newly designed pressure‐scanning capillary viscometer is extended to measure the viscosity of whole blood over a range of shear rates without the use of anticoagulants in a clinical setting. In the present study, a single measurement of pressure variation with time replaces the flow rate and pressure drop measurements that are usually required for the operation of a capillary tube viscometer. Using a pressure transducer and capillary, we measured the variation of pressure flowing through capillary tube with respect to time, p(t), from which viscosity and the shear rate were mathematically calculated. For water and anticoagulant‐added bloods, there was …an excellent agreement found between the results from the pressure scanning capillary viscometer and those from a commercially available rotating viscometer. Also, the pressure‐scanning capillary viscometer measured the viscosity of whole blood without heparin or EDTA. This new method overcomes the drawbacks of conventional viscometers in the measurement of whole blood viscosity. First, the pressure‐scanning capillary viscometer can accurately and consistently measure the whole blood viscosity over a range of shear rates in less than 2 min without any anticoagulants. Second, this design provides simplicity (i.e., ease of operation, no moving parts, and disposable) and low cost. Show more

Keywords: Blood, viscosity, shear rate, pressure, capillary viscometer

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 467-470, 2004

Authors: Varlet‐Marie, E. | Brun, J.‐F.

Article Type: Research Article

Abstract: Bioelectrical impedancemetry (BIA) has been used to evaluate hemorheological parameters from whole body measurements. In a previous study, we have determined a set of predictive equations for hematocrit, whole blood viscosity and plasma viscosity in athletes. In another previous study, we also found other predictive equations in sedentary lean and obese subjects. This study aims at developing more generalized BIA‐derived predictive equations for hemorheological parameters in both sedentary and trained individuals. 72 subjects, either athletes, sedentary obese or insulin resistant patients (33.57±1.60 yr; 80.81±2.06 kg; 171.03±1.19 cm) were enrolled into the study. Body composition was assessed with a multifrequency bioelectrical …impedancemeter (Dietosystem Human IM Scan) using low intensity at the following frequencies: 1, 5, 10, 50 and 100 kHz. Viscometric measurements were done at 1000 s−1 with a falling ball viscosimeter (MT 90 Medicatest). Hematocrit (Hct) was measured with microcentrifuge. Hematocrit was correlated with impedance (Z) measurements at 50 kHz (r=−0.591, p=0.01). A generalized empirical predictive equation can thus be proposed. These findings further suggest that one can predict hematocrit in the general population with whole body electric properties. Show more

Keywords: Impedance, body fluids, blood viscosity, hemorheology, hematocrit, athlete, sedentary population

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 471-475, 2004

Authors: Antonova, Mariya

Article Type: Research Article

Abstract: The viscoelastic characteristics – modulus of elasticity, natural frequency, coefficient of viscosity and low‐frequency resonance curve can be used as diagnostic indicators, at assessment of the direct effect of vasoactive drugs, and at selection of natural and artificial arterial prostheses. The aim of this work is a device for measurement of the viscoelastic characteristics of cylindrical segments of arteries in vitro and of arterial prostheses to be developed. The cylindrical segment is subjected to low frequency sinusoidal pulsations of the inner pressure. On the basis of the amplitude of the response oscillations of the wall, measured using the volume pulsations …of the segment, the resonance curve is built so that the dynamic characteristics – modulus of elasticity, natural frequency, and coefficient of viscosity can be calculated. The living specimens are perfused with nutrition solution for keeping the quasi‐physiological conditions. In the same way, cylindrical segments of rubber and artificial human prostheses were investigated. The sensitivity and the accuracy of the device are given. The construction permits to keep the vitality of native animal's specimens when the measurements are carried out. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 477-480, 2004

Authors: Zvetkova, E. | Savov, Y. | Gluhcheva, Y. | Ilieva, I. | Bichkidjieva, E. | Katzarova, E. | Tsenov, I.

Article Type: Research Article

Abstract: The morphological characteristics of granulocyte/macrophageal (GM‐) colonies and clusters, obtained in vitro (in semi‐solid agar cultures) from bone marrow hematopoietic myeloid progenitors pertain to leukocyte hemorheology of healthy persons and patients with myeloid leukemias. The morphological features of in vitro growing myeloid progenitors, granulocytes and macrophages of healthy persons differ in their cell size, shape and degree of differentiation from the cultivated marrow cells in cases of acute and chronic myeloid leukaemia. In this malignant disease, the rheological properties of leukocytes (granulocytes/macrophages) were found to provide diagnostic information. Further studies should be undertaken to examine whether the method could be …useful in defining survival, prognosis and therapeutical approach in cases of myeloid leukemia. Show more

Keywords: Human bone marrow agar cultures, granulocyte/macrophageal (GM‐) colonies and clusters in vitro, morphological/rheological features of myeloid cells, healthy persons and myeloid leukemia patients

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 481-484, 2004

Authors: Forconi, Sandro

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 485-486, 2004

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 487-495, 2004