Clinical Hemorheology and Microcirculation - Volume 17, issue 6

Authors: Rampling, Michael

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 395-396, 1997

Authors: Ajmani, Ranjeet S.

Article Type: Research Article

Abstract: Hemorheological disturbances in hypertension are the outcome of changes in red cell characteristics, their interaction in the presence of fibrinogen, and the magnitude and distribution of flow forces. Hemorheological alteration coupled with changes in biochemical variables and vessel characteristics in hypertension may affect the hemodynamic profile, which could possibly contribute to the development of hemorrhagic disorders. The complex pathophysiology of hypertension also depends upon the life style, presence of other risk factors, emotional/psychological stress, age and the genetic constitution of an individual. This review article summarizes the hemorheological changes in hypertension and their probable role in the deterioration of blood …flow. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 397-420, 1997

Authors: Caimi, Gregorio | Assennato, Pasquale | Canino, Baldassare | Montana, Maria | Ventimiglia, Giuseppe | Lo Presti, Rosalia

Article Type: Research Article

Keywords: Acute myocardial infarction, aortocoronary by‐pass, exercise test, leukocyte rheology, PMN membrane fluidity, PMN cytosolic Ca^{2+}

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 421-427, 1997

Authors: Caimi, Gregorio | Canino, Baldassare | Montana, Maria | Ferrara, Filippo | Ventimiglia, Giuseppe | Meli, Francesco | Romano, Adele | Catania, Anna | Lo Presti, Rosalia

Article Type: Research Article

Abstract: In 71 subjects with vascular atherosclerotic disease (VAD), in 32 VAD subjects with non‐insulin‐dependent diabetes mellitus (NIDDM) and in 31 normal controls, we evaluated polymorphonuclear leukocyte (PMN) membrane fluidity and PMN cytosolic Ca^{2+} content. The PMN membrane fluidity was obtained by marking intact and unstimulated PMN cells with fluorescent probe 1‐[4‐(trimethylamino)phenyl]‐6‐phenyl‐1,3,5‐hexatriene (TMA‐DPH) and the PMN cytosolic Ca^{2+} content was obtained by marking intact and unstimulated PMN cells with the fluorescent probe Fura 2‐AM. From the obtained results, it is evident that PMN membrane fluidity does not differentiate normals from VAD subjects and VAD subjects with NIDDM, …and normals from subjects with monovascular disease (MVAD) and polyvascular disease (PVAD) with and without NIDDM. The PMN cytosolic Ca^{2+} content is significantly increased in VAD subjects and VAD subjects with NIDDM, and also in MVAD and PVAD subjects with and without NIDDM. A positive correlation is present between PMN membrane fluidity and PMN cytosolic Ca^{2+} content in normals and VAD subjects, but not in VAD subjects with NIDDM. In conclusion, in VAD subjects with and without NIDDM, an increase of the PMN cytosolic Ca^{2+} content is present; this increase might be related to the PMN spontaneous activation. Show more

Keywords: Vascular atherosclerotic disease, non‐insulin‐dependent diabetes mellitus, polymorphonuclear membrane fluidity, polymorphonuclear cytosolic Ca^{2+}

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 429-436, 1997

Authors: Abugo, O.O. | Peddada, R.R. | Kelly, J.F. | Roth, G.S. | Rifkind, J.M.

Article Type: Research Article

Abstract: Four different groups of male Fisher rats were placed on one of the following diets for a period of one month: normal (control) diet, high cholesterol (HC) diet, high saturated fat (HF) diet and low fat (LF) diet. Subsequently, blood samples were drawn and washed in phosphate buffered saline (PBS), and the red cells were resuspended in the same buffer. These samples were introduced into a polycarbonate capillary flow system and their flow characteristics observed. In addition, the mean cell volumes (MCV) in isotonic PBS and the maximum swollen cell volume (MCV_{\max} ) in hypotonic PBS were determined using …a Coulter counter. From these, the mean surface area (MSA) and the excess surface area (ESA) were calculated. It was found that rats on a high cholesterol diet develop erythrocyte geometric characteristics which should contribute to improved capillary flow, namely, a decreased mean cell volume and an increased excess surface area. Nevertheless, in these rats a decreased capillary flow was observed as indicated by an increase in mean cell transit time, MCTT, and an appreciable drop in the number of cells per second passing through the capillary flow system. The flow and geometric properties of the high saturated fat and low fat fed rats did not differ significantly from those of the control group. Show more

Keywords: Erythrocytes, deformability, high cholesterol diet, capillary flow, cell geometry, mechanical properties

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 437-443, 1997

Authors: Peddada, R.R. | Abugo, O.O. | Kelly, J.F. | Roth, G.S. | Rifkind, J.M.

Article Type: Research Article

Abstract: Erythrocytes from male Fisher 344 rats on a high cholesterol diet (HC) exhibited a decreased ability to flow through capillaries when compared with those on a normal diet (control), a phenomenon which could not be explained by changes in geometric characteristics [1]. To explain these results, changes in capillary‐dependent rheological characteristics and intrinsic mechanical properties of red blood cells (RBC) due to diet were calculated. The hematocrit deficit in the capillary with respect to the reservoir was greater in the high cholesterol diet fed rats than in the control ones. This was attributed to an overall decrease in red cell …deformability which, in turn, was related to an increase in the membrane shear viscosity, the cytoplasmic viscosity, the membrane shear modulus of elasticity, and the membrane bending rigidity. By an independent calculation, we determined that the shear modulus of elasticity increased with a high cholesterol diet. The changes in both the capillary hematocrit deficit and the shear modulus of elasticity with a high cholesterol diet were found to be statistically significant (p\,{\scriptstyle\leq}\,0.05 ). Show more

Keywords: Erythrocyte, deformability, high cholesterol diet, capillary flow, apparent viscosity, Fåhraeus effect, intrinsic viscosity, membrane shear modulus of elasticity

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 445-457, 1997

Authors: Miao, Ge | Yan, Yan | Chuanmin, Zhang | Naiying, Li

Article Type: Research Article

Abstract: This paper is written in order to provide a scientific basis for laying out an unified standard of the reference value of hematocrit of Chinese healthy people. It studies the relationship between the reference values of Chinese adults’ hematocrit, tested according to the Wintrobe Laws and five geographical factors. It is found that the altitude is the most important factor affecting the reference value of Chinese healthy people’s hematocrit. As the altitude gradually increases, the reference value of their hematocrit also increases. By using the method of stepwise regression analysis, two multivariate regression equations are deduced. If the geographical index …values in a particular area are known, the reference value of Chinese healthy people’s hematocrit in this area can be established by means of the regression equations. Furthermore, according to the dependent relationship of the reference value of Chinese healthy people’s hematocrit to geographical factors, China can be divided into six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast district. Show more

Keywords: Hematocrit, reference value, geographical elements, altitude, regression analysis

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 459-465, 1997

Authors: Wen, Zong‐yao | Yan, Zong‐yi | Gao, Tie | Dou, Huanfu | Lu, Jingfen | Sun, Dagong | Lu, Zhihong

Article Type: Research Article

Abstract: With a new ektacytometry, we studied the relation between the microstructure of red blood cell (RBC) membrane and the rheological properties of RBCs in a shear flow field of low viscosity. The main contributions of this paper are as follows: 1. The hemorheological meanings of the orientation index (DI)_{\rm or} and the small deformation index (DI)_{\rm d} were explored. (DI)_{\rm or} is an overall rheological index depending on the deformability and morphology of RBCs. The better the physiological shape of RBCs is maintained, the greater the (DI)_{\rm or} is. (DI)_{\rm d} …can be used to describe the lipid fluidity of RBC membrane. Such an explanation for the meaning of (DI)_{\rm d} has been forcefully supported by our experiments using electron spin resonance (ESR) and fluorescence polarization. 2. The influence of wheat germ agglutinin (WGA) of different concentrations on the lipid fluidity of membrane is different from that of concanavalin A (ConA). The lipid fluidity of membrane changes with WGA concentration treating RBCs and there is a maximum value for the membrane fluidity at a specific concentration of WGA. However, the deformability of membrane described by the integrate deformation index (IDI) monotonically decreased with the increase in WGA concentration treating RBCs. 3. It is concluded that the increase in the lipid fluidity of red cell membrane is not necessarily associated with the improvement of RBC deformability. Show more

Keywords: New ektacytometry, lipid fluidity, deformability, red blood cell, membrane, hemorheology

Citation: Clinical Hemorheology and Microcirculation, vol. 17, no. 6, pp. 467-478, 1997