Clinical Hemorheology and Microcirculation - Volume 9, issue 1

Authors: Rampling, M.W. | Feher, M.D. | Sever, P.S. | Elkeles, R.S.

Article Type: Research Article

Abstract: There are many reports in the literature describing haemorheological disturbances associated with diabetes. However, the majority of these studies have concentrated on insulin-dependent, rather than non-insulin dependent diabetes (NIDD). Furthermore, very little attention has been given to the effect of associated hypertension which is a common feature of NIDD. In this study the rheological profiles of blood from 41 NIDD subjects with treated hypertension (HT), 31 normotensive NIDD subjects (NHT) and 12 non-diabetic controls (C) were studied. Differences in haematocrit failed to reach statistical significance. However, the plasma fibrinogen concentrations (mean ± SD) were significantly different between the groups (HT: …4.7 ± 1.0, NHT: 4.0 ± 0.7, C: 3.5 ± 0.6 g/l) and were reflected in the plasma viscosity (1.52 ± .15, 1.46 ± .06, 1.41 ± 0.6 mPas) and relative blood viscosity at low shear rate, 0.277 s−1 , (38.1 ± 3.8, 35.9 ± 3.9, 32.9 ± 3.6). The rheological differences between the groups can be explained mainly in terms of the effects of altered fibrinogen concentration. Show more

Keywords: Hemorheology, fibrinogen, diabetes, hypertension, blood viscosity, plasma viscosity

DOI: 10.3233/CH-1989-9110

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 101-107, 1989

Authors: Koppensteiner, R. | Jung, M. | Minar, E. | Ehringer, H.

Article Type: Research Article

Abstract: Hemorheological abnormalities in completed vascular stroke are frequently reported. The purpose of our study was to examine whether patients with recent transient ischemic attacks (TIAs) show similar changes. In 15 patients with recent TIAs hematocrit, fibrinogen, red cell aggregation, red cell deformability and platelet aggregation were studied. In comparison to age-and sex-matched healthy controls a significant elevation of platelet aggregation (spontaneous, ADP-induced) was found; no differences were observed in the other parameters. Our findings suggest that normal hemorheological conditions (apart from increased platelet aggregation) - as found in our TIA-patients - may advance the recovery from a neurological deficit by …more effective activation of hemodynamic compensating mechanisms. Show more

Keywords: transient ischemic attacks, platelet aqgregation, hemorheology

DOI: 10.3233/CH-1989-9111

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 109-114, 1989

Authors: Robertson, J.D. | Maughan, R.J. | Leiper, J.B. | Davidson, R.J.L.

Article Type: Research Article

Abstract: Haemorheologtcal and red cell age-related indices were measured in male subjects before and after two bouts of prolonged walking (148km) each lasting 4 days. During the walk subjects consumed isoenergetic diets which were either low (2 ± 0%, mean ± SD) or high (85 ± 1%) in carbohydrate (CHO). There was a significant reduction in the uncorrected whole blood viscosity only on the high CHO diet, primarily due to a greater extent of the haemodilution which was evident on both diets. In addition, plasma viscosity was significantly elevated on the low CHO diet but unchanged on the high CHO diet, …these dietary differences being associated with alterations in serum protein concentration. Red cell deformability was reduced only on the low CHO diet and there was also an increase in median cell density in Percoll gradients indicating general aging of the cell population. Increases in reticulocyte number and red cell creatine recorded only on the low carbohydrate diet (high protein and fat) are consistent with increased erythropoietic activity. Show more

Keywords: Blood viscosity, diet, exprclse

DOI: 10.3233/CH-1989-9112

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 115-124, 1989

Authors: Neumann, F.-J. | Haupt, H. | Zimmermann, R. | Tillmanns, H.

Article Type: Research Article

Abstract: Purpose of the study was to investigate the sensitivity of metal microsieves (pore diameter 4.3±.2 µm) for detecting changes in red cell deformability through red cell filtration by the hydrostatic pressure of the sample in the MF4 filtrometer. To estimate the effects of pore clogging and of single pore conductance separately in the MF4 filtrometer, a new method of evaluation was introduced and validated using the St. George’s filtrometer. To test the microsieves in the MF4 filtrometer, normal red blood cells (haematocrit 6%) were filtered in parallel with artificially abnormal cells: Internal viscosity and cell volume were altered by changing …suspension osmolality, membrane stiffness by heat treatment, and cell shape by incubation with Na-salicylate or chlorpromazine. The induced abnormalities caused a change in single pore conductance or clogging rate and were more easily detected by filtration through metal microsieves than through polycarbonate membranes. Hence, metal microsieves proved a useful tool in red cell filtration. Show more

Keywords: erythrocyte, filtration, microsieve, viscosity

DOI: 10.3233/CH-1989-9113

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 125-137, 1989

Authors: Brown, P. | Harrison, M.J.G.

Article Type: Research Article

Abstract: Platelet aggregation and blood filtrability were studied in patients with aortic Starr Edwards valves and xenograft valves and in age and sex matched patients with unoperated aortic valve disease and in controls. Blood filtrability was found to be significantly impaired in both patients with aortic valve disease and with Starr Edwards valve replacements. Platelet aggregation in stirred whole blood was found to be significantly greater only in patients with Starr Edwards valves. Red cell release of adenosine diphosphate under shear stress is thus unlikely to mediate the reduced platelet survival in vivo or the increased platelet aggregability in vitro seen …in patients with aortic Starr Edwards valves, and it is suggested that the platelets themselves are affected by contact with such prosthetic valves. The relevance of these findings to the risk of thromboembolism is discussed. Show more

DOI: 10.3233/CH-1989-9114

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 139-147, 1989

Authors: Takamizawa, Keiichi | Hayashi, Kozaburo | Nakamura, Takao | Kato, Tadashi | Tsushima, Nobuko

Article Type: Research Article

Abstract: The effects of elastase administration on the rheological properties of blood were investigated in the rabbits fed 1 % cholesterol diet for 14 weeks. There was no significant difference in the whole blood viscosity among the cholesterol-fed animals, cholesterol-fed and elastase administered ones and non-treated control ones. The hematocrit was lowest in the rabbits fed cholesterol diet. The filtrability (deformability) of red blood cell was also decreased by the cholesterol diet. These changes indicate the decrease in the capability of oxygen delivery on macro- and micro-circulation levels. The elastase administration improved the macrocirculatory oxygen delivery index in the hypercholesterolemic rabbits, …although it had no appreciable effect on the red blood cell deformability. Show more

Keywords: Cholesterol, Elastase, Hypercholesterolemic Rabbits, Oxygen Delivery, Blood Viscosity, Red Blood Cell Deformability

DOI: 10.3233/CH-1989-9115

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 149-156, 1989

Article Type: Abstract

DOI: 10.3233/CH-1989-9116

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 157-166, 1989

Authors: Ernst, E.

Article Type: Other

DOI: 10.3233/CH-1989-9117

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 167-172, 1989

Article Type: Announcement

DOI: 10.3233/CH-1989-9118

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 173-176, 1989

Article Type: Other

DOI: 10.3233/CH-1989-9119

Citation: Clinical Hemorheology and Microcirculation, vol. 9, no. 1, pp. 177-177, 1989