Clinical Hemorheology and Microcirculation - Volume 13, issue 5

Authors: Baker, Carl W. | Ward Anderson, Kimberly | Beaty, Mark M. | Schwartz, Richard W. | Dempsey, Robert J.

Article Type: Research Article

Abstract: This study determined whether the extent of atherosclerotic plaque buildup, smoking history, or serum cholesterol level could be correlated with red cell membrane deformability as determined by the micropipette aspiration technique. Smoking and non-smoking subjects 40 to 70 years old were grouped by atherosclerotic plaque thickness. A 50% increase (p≤0.01) in red cell membrane shear elastic modulus was seen in the advanced atherosclerosis group (plaque thickness = 2.0–4.0 mm). This increase was independent of the smoking history of the subjects. An increase in shear elastic modulus indicates a decrease in red blood cell membrane deformability. Other variables tested including age …and serum cholesterol level were not significantly correlated with red blood cell shear elastic modulus. Such changes in red cell deformability may play an important role in the pathophysiology of vascular occlusion and cerebral ischemia in patients with carotid artery atherosclerosis. Show more

Keywords: RBC deformability, Smoking, Atherosclerosis, Micropipette Aspiration, RBC elasticity

DOI: 10.3233/CH-1993-13511

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 671-678, 1993

Authors: Specht-Leible, N. | Schlierf, G. | Lang, P.D. | Neumann, F.J.

Article Type: Research Article

Abstract: Plasma fibrinogen is an independent risk factor of atherosclerosis. By altering lipid and plasma fibrinogen concentrations, bezafibrate modifies several factors which potentially affect progression of atherosclerosis. 23 male patients were randomized after successful PTCA. The bezafibrate group (n=11), in addition to diet, was given 200 mg bezafibrate three times daily. In the control group (n=12) there was usual care only. All patients received acetylsalicylic acid. Reassessment was after 6 months. Bezafibrate patients had a significant reduction of plasma fibrinogen from 340 ± 92 to 224 ± 29 mg/dl (p<0.05). The difference in fibrinogen concentrations within the 6 months was also …significant when the two groups were compared (p<0.05). Patients of the bezafibrate group had a significant decrease of plasma triglycerides from 297 ± 303 to 134 ± 64 mg/dl (p<0.05) and a significant increase in HDL-cholesterol (30 ± 13 to 48 ± 11 mg/dl, p<0.05), apolipoproteins A1 (116 ± 19 to 138 ± 18 mg/dl, p<0.05) and apolipoproteins A2 (41 ± 8 to 56 ± 7 mg/dl, p<0.05). Changes in HDL-cholesterol and apolipoproteins A1 and A2 were also significant (p<0.05) when the two groups were compared after 6 months. Restenoses were found in 11 of the 23 patients (47.8%), 4 restenoses in the 11 bezafibrate patients and 7 restenoses in the 12 usual care patients. A potential efficacy of bezafibrate in the prevention of restenosis may be related to the drug's effects on plasma fibrinogen. Show more

Keywords: bezafibrate, fibrinogen, hemorheology, PTCA, restenosis

DOI: 10.3233/CH-1993-13512

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 679-685, 1993

Authors: Laghi Pasini, F. | Capecchi, P.L. | Ceccatelli, L. | Buccianti, N. | Franchi, M. | Provvedi, T. | Acciavatti, A. | Frigerio, C. | De Giorgi, L. | Di Perri, T.

Article Type: Research Article

Abstract: In order to clarify some aspects of cell involvement in the mechanism of tissue injury during ischaemia, haemoreological parameters and polymorphonuclear leukocyte (PMN) function were studied in patients affected with peripheral obliterative arterial disease (POAD) undergoing treadmill test and isotonic ischaemic exercise at an upper limb. In POAD patients, ischaemia was associated with an impairement in haemorheological parameters, in regional as well as in systemic blood. During treadmill test, cytosolic free calcium levels in resting PMNs from systemic blood increased significantly, while no significant change was observed in the response to fMLP stimulation. Superoxide anion generation from PMNs increased only …for sub-maximal doses of fMLP (0.01 μM). Conversely, isotonic ischaemic exercise was accompanied by a significant increase in cytosolic free calcium levels in resting and fMLP-activated PMNs in the blood from the ischaemic area, as well as in superoxide anion generation from 1 μM fMLP-stimulated cells. Moreover, an increase in PDGF and ATP plasma levels was also observed, as an expression of platelet activation, possibly inducing PMN priming. Our data support the view that PMN activation is associated with rheological impairement and tissue damage occurring in the course of ischaemic events. Show more

Keywords: Haemorheology, ischaemia, neutrophils, ATP, PDGF

DOI: 10.3233/CH-1993-13513

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 687-699, 1993

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

Article Type: Research Article

Abstract: At a constant haematocrit ratio the yield shear stress (YSS) depends on the level of fibrinogen and on the influence of other plasma constituents, erythrocyte membrane changes on the red cells and fibrinogen interaction. The study of the influence of the H.E.L.P. system on the value of YSS was carried out in 9 patients with vascular disease (acute stroke - 3 patients -, multi-infarct dementia - 3 patients -, peripheral arteriosclerotic vascular disease - 2 patients - and coronary heart disease - 1 patient) in the model of diluted plasma media varying in fibrinogen concentration. The H.E.L.P. system application significantly …decreased the value of YSS (p<0.001), which was related to the parallel reduction of the fibrinogen level (p<0.001) and plasma viscosity (p<0.001). The significant coefficients of correlations were found out between following parameters: YSS and fibrinogen (p<0.001), YSS and plasma viscosity (p<0.001) and fibrinogen and plasma viscosity (p<0.001) . Show more

Keywords: vascular disease, H.E.L.P. system, YSS

DOI: 10.3233/CH-1993-13514

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 701-706, 1993

Article Type: Abstract

DOI: 10.3233/CH-1993-13515

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 707-712, 1993

Article Type: Other

DOI: 10.3233/CH-1993-13516

Citation: Clinical Hemorheology and Microcirculation, vol. 13, no. 5, pp. 713-713, 1993