Clinical Hemorheology and Microcirculation - Volume 21, issue 3-4

Authors: Turchetti, V. | Bellini, M.A. | Guerrini, M. | Forconi, S.

Article Type: Research Article

Abstract: The aim of our study was to evaluate hemorheological parameters in two groups of patients both suffering from essential hypertension compared with an homologous group of subjects not suffering from hypertension; the 1st group was composed of 16 patients (8 females and 8 males, mean age 65.6 \pm 16.5) suffering from essential hypertension; the 2nd one of 26 patients (8 females and 18 males, mean age 74.3 \pm 11.7) suffering from essential hypertension and cerebral or cardiac ischemia in a chronic phase. The group of controls was composed of 20‘subjects (mean age 50.5 \pm …11.5). In all these subjects we evaluated: blood viscosity, hematocrit, plasmatic fibrinogen, red cell morphology according to Zipursky–Forconi method and blood pressure. Our results show that blood viscosity and fibrinogen were statistically increased relative to controls. Comparison between these groups leads us to observe that blood viscosity and fibrinogen are slightly higher in the first group in a statistically significant way (7.5 \pm 1.1 cPs 10 s^{-1} 1st group, 7.9 \pm 1.05 cPs 10 s^{-1} 2nd group; 362.2 \pm 167.3 mg% 1st group, 384.6 \pm 106.9 mg% 2nd group). Blood pressure was higher in the second group. The study of red cell morphology in all the patients showed a prevalence in the percentage of discocytes, cells which have less deformability compared to bowls. The study demonstrated EMI (Erythrocyte Morphology Index) decreased in a statistically significant way compared to controls (0.70 \pm 0.03 1st group; 0.65 \pm 0.02 2nd group; 1.2 \pm 0.09 control group). In subjects suffering from essential hypertension with end‐organ damage EMI further decreases. So we observed that hypertension is also delineated by the increase in the discocytes percentage which results in reduction of the red cell deformability. In conclusion, when hypertension causes end‐organ damage, the hemorheological alterations, which implicate a worsening in microcirculation, are more evident. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 285-289, 1999

Authors: Wang, X. | Zhao, H. | Zhuang, F.Y. | Stoltz, J. F.

Article Type: Research Article

Abstract: The aim of this work is to study the deformability of red blood cells (RBC) by two laser diffraction methods: the Laser‐assisted Optical Rotational Cell Analyser (LORCA, Mechatronics, Amsterdam, Netherlands) and a Shear Stress Diffractometer (RHEODYN SSD, Myrenne, Roetgen, Germany). Experiments were carried out on 46 healthy human subjects. The elongation index EI of normal and hardened RBCs (obtained by heating blood at 49{}^\circ C or by incubating RBCs in solutions of diamide) was measured. The results showed that the standard deviations of the experimental data for normal RBCs were relatively small, especially at high shear stresses (more than …3.0 Pa), but higher than those reported before. Some correlations between the results given by the two instruments were also found. It should be noted that for hardened RBCs, the standard deviations of the measurements were important compared with the mean values in the two instruments. Show more

Keywords: RBCs deformation, laser diffraction, shear stress

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 291-295, 1999

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

Article Type: Research Article

Abstract: The aim of this work was to evaluate three optical methods designed to determine erythrocyte aggregation: Erythroaggregometer (EA; Regulest, France), Laser‐assisted Optical Rotational Cell Analyzer (LORCA; Mechatronics, Netherlands) and Fully Automatic Erythrocyte Aggregometer (FAEA; Myrenne, GmbH, Germany). Blood samples were taken from fifty donors (26 males and 24 females). The aggregation of normal red blood cell (RBC) and RBCs suspended in three normo‐ and hyper‐aggregating suspending media was studied. The results revealed some significant correlations between parameters measured by these instruments, in particular, between the indexes of aggregation of EA and LORCA. Further, RBC aggregation of multiple myeloma patients was …also studied and a hyper erythrocyte aggregation state was found by EA and LORCA. Show more

Keywords: Erythrocyte aggregation, laser back‐scattering, multiple myeloma, shear stress

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 297-302, 1999

Authors: Federico, P. | Ragozzino, G. | Del Guercio, M. | Mattera, E. | Del Guercio, R.

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 303-305, 1999

Authors: Lugarà, P.M.

Article Type: Research Article

Abstract: The optical oxymetry methods based on light transmission or diffuse reflectance of living tissues are discussed. The experimental techniques now under test are highlighted.

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 307-310, 1999

Authors: Cicco, G.

Article Type: Research Article

Abstract: In order to evaluate the oxygen saturation of hemoglobin in living tissues we use a new experimental instrument: the optical oximeter (LOX). The LOX uses 2 LEDs, like the pulse oximeter (PO). One LED operates at 670 nm (Hb absorption), the other one operates at 830 nm, i.e., near the isosbestic point for which Hb and HbO_2 show the same extinction. The oxygen saturation of Hb can be expressed as a linear function of the ratio of the absorption coefficients at the wavelengths of the 2 LEDs. Indeed the LOX is based on diffused reflectance measurements and not …on light transmission such as the POs. We studied in standard conditions 10 healthy volunteer subjects (6 M, 4 F aged 40 \pm 4 years) non smokers. We used TO (Combi Sensor) at the subclavicular standard area and at the right ankle, PO with the probe always at 2nd finger of the right hand and LOX at right wrist and at right ankle. We obtained a significant relationship between values of TO, PO and LOX (p<{} 0.01). Our preliminary data suggest that this could be a new methodology to evaluate tissular oxygenation, also exploring living tissues several centimeters deep. Show more

Keywords: Tissue oxygenation, microcirculation, optical oximetry

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 311-314, 1999

Authors: Cicco, G. | Vicenti, P. | Stingi, G.D. | Tarallo, M.S. | Pirrelli, A.

Article Type: Research Article

Abstract: During essential and secondary arterial hypertension it is possible to observe changes in microcirculation perfusion associated with a reduction in tissue oxygenation due in part to hemorheological changes such as an increase in blood viscosity or the formation of the red blood cell “rouleaux” which favour an increase in peripheral resistance and can cause or worsen arterial hypertension. We studied 21 healthy subjects (11 male and 10 female aged 42{}\pm{} 4) and 26 hypertensive subjects (14 male and 12 female aged 49{}\pm{} 3). The patients were non smokers and non suffering from respiratory or haemathological pathologies. They …were not undergoing antihypertensive or vasodilatory pharmaceutical treatment. The patients suffered from mild hypertension (II WHO) with Peripheral Occlusive Arterial Disease (POAD II “a” acc. to Leriche–Fontaine class.). The patients showed an increase in cholesterolaemia (6.42{}\pm{} 0.81 mmol/l) and trygliceridaemia (2.73{}\pm{} 0.09 mmol/l) at an average level. The patients were studied in standard conditions with a constant temperature of 22{}^\circ C. We measured SBP, DBP, MBP, and the HR. We also measured the elongation index (EI) (with shear stress range 0.30 to 30 pascals) using LORCA, acc. to Hardeman method (1994), in order to study the erythrocyte deformability and aggregation kinetics in dynamic condition. To evaluate deformability in static conditions we calculated the Erythrocyte Morphologic Index (EMI), acc. to Forconi method, via the bowl/discocyte ratio (for 100 red blood cells fixed in glutaraldehyde at 0.3% and observed with an optical microscope under immersion in glycerol). Peripheral oxygenation was taken transcutaneously (TcpO_{2} ). To establish the level of vascular disease we used the Regional Perfusion Index (RPI{}={} TcpO_{2} foot/ TcpO_{2} subclavean) and doppler guided Winsor Index (WI). The Student “t ” test and linear regression were used for the statistical analysis. Our data confirm a reduction in peripheral tissue oxygenation in hypertensives especially if suffering from vascular disease which correlates significantly (p<{} 0.01) with a reduction in red blood cell deformability. This itself can increase peripheral resistances and favour the onset of hemorheological complications, at a cerebral‐vascular level, which are frequent in hypertensives. Show more

Keywords: Hemorheology, hypertension, lipoidoproteinosis, vasculopathy

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 315-319, 1999

Authors: Kowal, Piotr

Article Type: Research Article

Abstract: In a group of 36 patients with acute ischemic stroke, the study of influence of arterial hypertension on the red cells and fibrinogen interaction was carried out by the aspect of fibrinogen molecules contribution to this phenomenon, respecting the role of other plasma biochemical factors. Patients were divided into two clinical groups: with and without arterial hypertension. In the blood samples with stable haematocrit ratio the following rheological properties were estimated: plasma viscosity, yield shear stress (YSS), fibrinogen level and parameter R (the difference between twice measurements of fibrinogen concentration). There were also measured the levels of albumin, IgG, IgA, …IgM, cholesterol, HDL and LDL. The value of parameter R in patients with arterial hypertension was lower than the group without accompanying disease (statistical significance was indicated for 80% and 60% of plasma dilution). The first group of patients was also characterized by significant increase of IgA level (in comparison with the control group), whereas the red cells and fibrinogen interaction measured as a value of YSS was similar in both analyzed clinical groups. This study indicated a specific character some of hemorehological changes in relation to a certain vascular pathology. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 321-324, 1999

Authors: Chmiel, Bogdan | Olszowy, Zofia | Turczynski, Boleslaw | Kusmierski, Stanislaw

Article Type: Research Article

Abstract: Although blood pressure is in most cases determined genetically, environmental factors such as obesity or alcohol consumption are implicated in the development of hypertension. On the other hand it is well known that alcohol drinking and hypertension are associated with reduction of red blood cells deformability. Aim: To compare the effect of ethanol on arterial pressure and red cell deformability in well controlled experimental conditions. Methods: Five healthy volunteers, men with age range between 26–38 underwent ethanol consumption 1.0 g per kg of body weight during 10 min period. Before and 90 min, 3 h and 5 h …after ethanol consumption arterial pressure, heart rate, blood morphology, alcohol and acetaldehyde blood level and deformability index by Rheodyn SSD were measured. Results: After ethanol consumption rise in ethanol and acetaldehyde blood levels and no changes in blood pressure, but significant increase in heart rate were observed. Elongation index of red blood cells at low shear rates has not been changed. At shear stresses of 12.0, 30.0 and 60 Pa significant increase in elongation index of erythrocytes after 1.5 hour of ethanol intake had occurred. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 325-328, 1999

Authors: Le Devehat, C. | Khodabandehlou, T. | Vimeux, M.

Article Type: Research Article

Abstract: The present study was designed to investigate whether the Veno‐Arteriolar Reflex (VAR) mediated via a local nervous reflex mechanism may be used as a microvascular approach to predict the effect of vasoactive drugs in diabetic patients. The vasoactive drug we studied here was Buflomedil. The effect of a single infusion of 400 mg of Buflomedil was examined on VAR and on transcutaneous oxygen pressure (TcPO_2 ). Investigations were performed in 42 diabetic patients. The VAR was assessed on dorsal foot and dorsal big toe by measuring changes in skin blood flux induced by lowering the leg. TcPO_2 …was measured on dorsal foot. Before Buflomedil infusion, patients were characterized by a loss of the VAR in comparison to healthy volunteers. The loss of the VAR was associated to significant decreases in TcPO_2 values. Buflomedil infusion led to significant increases in VAR at the two sites of measurement and also in TcPO_2 values. These findings indicate that the VAR can be used as a sensitive microvascular test, as it allows to detect the effect of Buflomedil. Furthermore, our findings demonstrate that the Buflomedil‐induced improvement in VAR is identical in the two diabetic groups with or without complications. This result emphasizes the benefit of Buflomedil not only in diabetics with microangiopathy or those suffering from a peripheral vascular disease for reducing pain or healing trophic lesions, but also in those patients without any clinically detectable macro‐ or microangiopathy in order to prevent or to reduce as long as possible the risk of developing diabetes related complications by the normalization of functional microangiopathy. Show more

Keywords: Diabetes, venoarteriolar reflex, transcutaneous oxygen pressure, Buflomedil

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 329-334, 1999

Authors: Izzo, P. | Manicone, A. | Spagnuolo, A. | Lauta, V.M. | Di Pasquale, A. | Di Monte, D.

Article Type: Research Article

Abstract: The erythrocytes deformability of three blood samples coming from healthy donors has been evaluated by Laser‐assisted Optical Rotational Cell Analyzer (LORCA). Blood samples were stored in CPD SAG‐mannitol. The study of progressive reduction in the Elongation Index (EI) during the preservation may be used as way of evaluation of erythrocyte vitality in stored blood samples.

Keywords: Erythrocytes deformability, LORCA, storage of red cells, CPD SAG‐mannitol

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 335-339, 1999

Authors: Ciccone, M. | Pestrichella, V. | Rossi, O. | Maiorano, A. | Modugno, M. | De Pergola, G. | Giorgino, R. | Rizzon, P.

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 341-342, 1999

Authors: Cicco, G. | Dolce, E. | Vicenti, P. | Stingi, G.D. | Tarallo, M.S. | Pirrelli, A.

Article Type: Research Article

Abstract: In postmenopausal hypertensive women (PostMHW) the erythrocyte deformability (ED) is reduced if compared with premenopausal hypertensive women (PreMHW). This might partially explain the increased incidence of cardiovascular diseases (CD) in hypertensive women after menopause. Moreover a positive correlation exists between estradiol and rheological patterns in women. If PostMHW smoke cigarettes, there is an important decrease in hemorheological parameters. On the other hand if PostMHW are submitted to an hormonal replacement therapy (HRT) they can show controversial results with an impairment if hemorheological parameters. The aim of this study was to evaluate the influence of smoking and HRT on PostMHW. …We studied four groups of subjects: Group 1: PreMHW (10 F aged 35{}\pm{} 3 years) non smokers; Group 2: PostMHW (8 F aged 45{}\pm{} 2 years) non smokers; Group 3: PostMHW (14 F aged 48{}\pm{} 4 years) smokers (20 cigarettes per day); Group 4: PostMHW (16 F aged 50{}\pm{} 2 years) smokers (20 cigarettes per day) submitted to HRT. We evaluated Elongation Index of erythrocytes under torsion force of 30 pascals (EI – 30 Pa) using a new computerized instrument Laser assisted Optical rotational Red Cell Analyzer (LORCA) (Mechatronics, Hoorn, NL) acc. to Hardeman (1994) and, also with the same LORCA, Aggregation Index (AI), t. We measured the transcutaneous oxygen partial pressure (TcpO_{2} ) in subclavicular standard area using a Transcutaneous Oximeter (Microgas 7650 Kontron Instruments with Combi Sensor) and total cholesterolaemia. In PostMHW our data showed a significant (p<{} 0.01) impairment of hemorheological patterns and tissue oxygenation if compared with PreMHW (Group 1). In Group 3 there is a significant (p<{} 0.01) decrease in EI, a significant (p<{} 0.01) increase in AI, a significant (p<{} 0.01) decrease in t and TcpO_{2} if compared with Control Group 1 and Group 2. Finally a further significant (p<{} 0.01) impairment in hemorheology and tissue oxygenation showed Group 4. In conclusion, it seems necessary, that many studies will be performed to understand really protective action of HRT on cardiovascular diseases in PostMHW and it is necessary to suppress cigarette smoking to prevent cardiovascular complications in these patients. Show more

Keywords: Hemorheology, menopause, hormonal replacement therapy, LORCA

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 343-347, 1999

Authors: Vetrugno, Michele | Gigante, Gaetano | Cardia, Luigi

Article Type: Research Article

Abstract: Purpose: to assess the effects on choroidal perfusion of scleral buckling and vitrectomy procedures for retinal detachment. Methods: 17 patients were included in the study: 7 underwent scleral buckling and 10 vitrectomy, for rhegmatogenous retinal detachment. pOBF Langham system evaluation was performed before and after surgery (the fellow eye served as control). Statistical analysis was based on paired t ‐test. Results: in the scleral buckling group was found a mean change (SD) of 470 (355.32) \mu l/min; in the vitrectomy group the mean difference (SD) was 254.2 (132.53) \mu l/min. In both groups a statistically …significant difference with the control was found. Conclusions: our results show that both surgical procedures affect choroidal perfusion and could impair optic nerve head feeding. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 349-352, 1999

Authors: Pollari, G. | Antonini, V. | Izzo, A. | Moreschini, G. | Serraino, M. | Tonelli, V. | D’Angiolino, A. | Migliaccio, M.

Article Type: Research Article

Abstract: In chronic respiratory insufficiency secondary erythrocytosis (SPC), causing pulmonary hypertension and dx ventricular insufficiency, is often noticed. An alternative therapy to phlebotomy for SPC is isovolemic large volume erythrocytapheresis performed with cell separator (CSE) in order to quickly remove a large volume of red blood cells (RBC) while saving plasma proteins and clotting factors. In order to evaluate the efficiency and safety of CSE in SPC we reported a retrospective analysis of our experience with 61 SPC patients: from April 1996 to May 1998 we performed 208 CSE using Haemonetics MCS3P (TAE protocol). Before every apheresis procedure we verified Hb …(in median 18.8 g/dl), Ht (in median 58.4%), viscometry, coagulation test, EGA, PFR and ECG. 11 patients were treated with 1 CSE, 12 with 3, 29 with 4 and 9 with 5. The mean volume of RBC removed was 576 ml (range 426–800); Hb post CSE averaged 14.4 g/dl and Ht post CSE averaged 42.7%; hematic viscosity post CSE was significantly reduced while tissue oxygen tension increased: the improvement of symptomatology and hematochemical parameters was maintained on the average for 6.5 months. All the procedures were well tolerated and light side effects (paresthesias citrate‐depending in 27 apheresis) were easily controlled. CSE, compared to phlebotomy, has the advantage of selectively removing RBC without loss of clotting factors, platelets and plasma proteins. Although CSE has relatively high costs we noticed a decrease of hospital recurrence (about 50–65%) in SPC patients treated with apheresis. Show more

Keywords: Erythrocytapheresis, polycythemia, chronic obstructive pulmonary disease, viscometry

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 353-355, 1999

Authors: Kameneva, M.V. | Watach, M.J. | Borovetz, H.S.

Article Type: Research Article

Abstract: According to official statistical data there is a significant difference between pre‐menopausal women and age‐matched men in morbidity and mortality from cardiac diseases and especially from myocardial infarction. There are several speculations regarding the nature of this phenomenon which have both supporting and refuting evidence. Our hypothesis was that due to regular physiologic bleeding, rheological properties of blood of pre‐menopausal women are superior to those of men, and place such women at a lower risk of cardiovascular diseases than men in any age group. We believe that this difference in hemorheological properties is due to the reduced concentration of …red blood cells (RBCs) and due to greater population of younger and less population of older RBCs in female blood. We studied mechanical properties of blood from 47 pre‐menopausal women and 50 age‐matched men. Compared to female blood, male blood had higher viscosity and RBC aggregation and lower RBC deformability. Oxygen Delivery Index, calculated as a ratio of hematocrit to blood viscosity, was found to be significantly lower in male blood. Decreased oxygen delivery along with increased RBC aggregation and decreased RBC deformability may contribute to the higher risk for the development of cardiovascular diseases. Regular blood donation may reduce hematocrit and blood viscosity, improve rheological properties of blood, and increase oxygen delivery in men. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 357-363, 1999

Authors: Ciccone, M. | Maiorano, A. | De Pergola, G. | Minenna, A. | Giorgino, R. | Rizzon, P.

Article Type: Research Article

Abstract: The objective of the present study was to determine whether the intima‐media thickness (IMT) is independently related with obesity, and central fat accumulation in healthy subjects. Common carotid artery IMT, parameters of body fat accumulation and distribution (body mass index, waist circumference, waist‐to‐hip ratio), blood pressure levels, and circulating fasting insulin, glucose, and lipid (cholesterol, HDL‐cholesterol, triglycerides, LDL‐cholesterol) levels were determined in a population of non‐diabetic normal weight and obese subjects. Smoking habits (packs‐years) were also taken into account. 239 healthy subjects (143 women and 96 men), with age ranging between 18 and 45 years, were enrolled into the study. …They were divided indo two groups according to the body mass index (BMI), obese (132 subjects, 77 woman and 55 men, with BMI greater than 27.0) and controls (107 subjects: 66 women and 41 men, with BMI lower than 27.0). Common carotid artery intima‐media thickness was measured by B‐mode ultrasound imaging. Fasting plasma metabolic parameters (glucose and lipids) and insulin levels were determined by enzymatic and radioimmunological assays, respectively. Insulin sensitivity was estimated by insulin tolerance test (ITT) and the rate constant for plasma glucose disappearance (KITT) during the 3‐ to 15‐min period following the regular insulin injection was taken as a measure of in vivo insulin action. Obese patients showed higher IMT than controls, and IMT was significantly associated with BMI in the whole population (r={} 0.316, p<{} 0.001). Age (r={} 0.327, p<{} 0.001), KITT (r=-0.201 , p<{} 0.01), fasting blood glucose (r={} 0.187, p<{} 0.01), LDL‐chol (r={} 0.201, p<{} 0.01), smoking (r={} 0.147, p<{} 0.05), MBP levels (r={} 0.154, p<{} 0.05), cholesterol (r={} 0.152, p<{} 0.05) and HDL‐chol (r=-0.159 , p<{} 0.05) were also significantly associated with IMT. Age (r={} 0.330, p<{} 0.05), BMI (r={} 0.299, p<{} 0.01),waist (r={} 0.312, p<{} 0.001), WHR (r={} 0.266, p<{} 0.001) and KITT (r=-0.259 , p<{} 0.01) were the parameters most strongly correlated with IMT in women, and age (r={} 0.324, p<{} 0.001), BMI (r={} 0.338, p<{} 0.001) waist (r={} 0.325, p<{} 0.001) and LDL‐chol (r={} 0.283, p<{} 0.01) where the parameters most strongly correlated with IMT in men. When a stepwise multiple regression analysis was performed for the whole population, only age (p<{} 0.001) and BMI (p<{} 0.001) maintained a significant positive relationship with IMT. When a stepwise multiple regression analysis was performed separately for men and women, BMI or waist circumference or WHR were alternatively entered into the model; interestingly, only age, BMI and waist were still significantly correlated with IMT, whereas WHR did not maintain a significant correlation with IMT. In conclusion, BMI and waist circumference, but not WHR, are strongly and independently associated with the IMT of common carotid artery. These results suggests that central fat accumulation may accelerate the development of earlier clinically silent stages of atherosclerosis, thus possibly explaining the higher prevalence of cardiovascular diseases in patients with abdominal obesity. Show more

Keywords: Obesity, central fat, intima‐media thickness, atherosclerosis, cardiovascular risk

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 365-374, 1999

Authors: Labrador, V. | Legrand, S. | Muller, S. | Carl, P. | Senger, B. | Voegel, J.‐C. | Latger‐Cannard, V. | Stoltz, J.‐F.

Article Type: Research Article

Abstract: The adhesion of polymorphonuclear leukocytes (PMNs) on the vascular endothelium is a complex process that occurs during biological and pathological events and involves a large family of molecules. This phenomenom could be approached by a modelisation study of the adhesion of PMNs on a biological substrate, fibrinogen. Two different physiological conditions were tested such as the activated state of PMNs with a synthetic pro‐inflammatory activator (N‐Formyl‐Methionyl‐Leucyl‐Phenylalanin, FMLP). The activated state of PMNs was both quantified by flow cytometry and controlled by fluorescence microscopy. The results suggest that quiescent PMNs deposit in accordance with the ballistic deposition model. The preliminary …results obtained with FMLP‐stimulated PMNs show a different deposit process compared to quiescent PMNs but do not allow to determine exactly a deposition model. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 375-382, 1999

Authors: Alexandratou, E. | Yova, D. | Cokkinos, D.V.

Article Type: Research Article

Abstract: Digital imaging microscopy plays an important role in computer aided cytological and histological diagnosis. In this study, digital imaging microscopy was used to measure Red Blood Cells (RBCs) morphometric characteristics such as area, perimeter, major and minor axis length, elongation, compactness and roughness in both groups: healthy individuals and Coronary Artery Disease (CAD) patients. All the measured characteristics, except elongation, showed a statistically significant difference between the two groups. In particular, patients with CAD presented greater values than healthy ones. Finally multivariate analysis was used in order to take into account the whole measured profile of each patient. Compactness, perimeter …and elongation improved the diagnostic ability, whereas all the others did not show any significant improvement. These three characteristics correctly classify the 84.5% of the patients. In conclusion, RBCs morphometric characteristics could be considered as diagnostic factors for CAD. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 383-388, 1999

Authors: Casavola, C. | Paunescu, L.A. | Fantini, S. | Franceschini, M.A. | Lugarà, P.M. | Gratton, E.

Article Type: Research Article

Abstract: Near‐infrared spectroscopy (NIRS) is a noninvasive technique to measure the tissue oxygenation in real time. This optical method has many advantages over the invasive analysis currently used for clinical tests. Among the possible applications of near‐infrared oxymetry, we report three protocols (exercise, venous occlusion and tilting table) in conjunction with NIRS, and discuss their applicability in the diagnosis of peripheral vascular disease (PVD).

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 389-393, 1999

Authors: Pascazio, L. | Regina, G. | Perilli, F. | Caputo, G. | Gigli, A. | Lamberti, P.

Article Type: Research Article

Abstract: 100 patients (pts) receiving CEA (carotid endarterectomy) were evaluated in this study. In some of them postoperative complications were observed, characterized by TIA (transient ischemic attack) and, mostly, by cerebral hyperperfusion. In only two of the pts investigated CEA needed the implantation of a shunt, due to the emergence of intolerance signs at carotid Clamping (C) evaluated by TCD (transcranial Doppler); the preoperative cerebral angiography in the two subjects in question did not show malformations of the circle of Willis. The hyperperfusive phenomenon and the absence of intracranial compensation flows during CEA seemed to be ascribed to a more or …less severe impairment of cerebral reserve. Such impairment of the autoregulatory capacity seems to be crucial to the pathogenesis of hemodynamic stroke. Thus the indication to CEA, in pts with severe carotid disease, should take into account also the cerebral reserve (CR) impairment to prevent both thromboembolic and hemodynamic stroke. The predictive and diagnostic role of TCD turns out to be crucial in assessing and selecting pts candidate to CEA. Show more

Keywords: Carotid endarterectomy, transcranial Doppler, cerebral reserve, hyperperfusion syndrome, carotid disease, hemodynamic stroke

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 395-403, 1999

Authors: Antonova, Nadia | Velcheva, Irena

Article Type: Research Article

Abstract: Whole blood and plasma viscosity were measured of 90 patients with chronic cerebrovascular disease (CVD) and 56 healthy individuals by Couette rotational viscometer Contraves Low Shear 30 at a steady flow. Plasma viscosity was measured with capillary viscometer of Ubbelohde type. Two subgroups of patients were investigated: 23 patients with transient ischemic attacks (TIAs) and 67 patients with chronic cerebral infarctions (CCI). They were compared with two control groups: 56 healthy individuals without risk factors for stroke and 37 randomly selected subjects with risk factors for stroke. It is established significant elevation of plasma viscosity in the patients with cerebral …ischemia. The elevation of blood viscosity was most pronounced at shear rate of 94.5 s^{-1} . This comparison is confirmed by the criterion, using blood rigidity number h defined by the formula of Whittington and Harkness. Conclusion is drawn from our study that chronic ischemic cerebrovascular disorders are characterized with chronic hyperviscosity. Show more

Keywords: Cerebrovascular disease, blood and plasma viscosity, blood rigidity number

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 405-408, 1999

Authors: Battistelli, Sandra | Manasse, Giacomo | Gubbolini, Michele | Landini, Tommaso | Coratti, Andrea

Article Type: Research Article

Abstract: The aim of this study was to investigate the behaviour of circulating ET‐1 in patients with carotid atherosclerosis, before and after carotid thromboendarterectomy (TEA), to test the hypothesis that plasma ET‐1 decreases after removal of atherosclerotic lesion. Plasma immunoreactive ET‐1 levels were determined in 17 patients with symptomatic and/or hemodynamically significant carotid atherosclerosis on the day before TEA, 48 h and 72 h after surgery and, in 11 of them, also after 8 h and 24 h. Compared to controls, ET‐1 levels were significantly higher both before and after TEA; after carotid revascularisation (8 h) ET‐1 increased; then, from the …24th h, ET‐1 gradually decreased and at the 48th h and 72th h the decrease was significant in front of basal values. The increase of plasma ET‐1 in the acute postoperative phase may reflect the degree of surgical stress and manipulation in diseased blood vessels; the following decrease may indicate the improvement of vascular dysfunction in the involved carotid site; the persistence of high ET‐1 levels 72 h after surgery could suggest the presence of residual ischemia in the involved district and/or the involvement of other sites in ET‐1 production. Show more

Keywords: Endothelins, atherosclerosis, carotid endarterectomy

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 409-414, 1999

Authors: Aigbe, A. | Famodu, A.A.

Article Type: Research Article

Abstract: Hypertension is the most significant cardiovascular risk factor to emerge in developing countries. 64 hypertensives (40 old hypertensives and 18 newly diagnosed hypertensives) and 40 age and sex matched normotensives controls were studied. Plasma fibrinogen concentration (PFC), euglobulin lysis time (ELT) and relative plasma viscosity (RPV) and relative whole blood viscosity (RWBV) were estimated. The PFC, RPV, RWBV and ELT were significantly higher in new and old hypertensives (P<{} 0.005), respectively, compared with controls. while the RPV was significantly higher (P<{} 0.005) in new hypertensives than old hypertensives. The significantly higher PFC, RPV and ELT in new hypertensives …correspond to higher BP in the new hypertensives than old hypertensives. There were consistence significance levels in PFC, RPV and ELT in both female hypertensives and controls (P<{} 0.005), respectively, with higher BP in male than female. Though there were no significant mean differences between the hypertensive patients in the first two years of the disease, there were cumulative consistent increase in fibrinogen levels and euglobulin lysis time from two years; while RPV shows inconsistence variation until the 5th year. We conclude that a defective rheology and fibrin‐clearing mechanism may contribute to aetiology of vascular complications in hypertensive patients especially in the long term. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 415-420, 1999

Authors: Passavanti, G. | Cicco, G. | Baldassarre, G. | Vicenti, P. | Soleti, F. | Stingi, G.D. | Carbonara, M.C. | Coratelli, P. | Pirrelli, A.

Article Type: Research Article

Abstract: We studied the effect of some dialytic membrane on tissular oxygenation (TO) and erythrocyte deformability (ED). Sixteen patients (10 M and 6 F, aged 59 \pm 12 years) have been submitted to bicarbonate dialysis (BD) and subdivided into four groups (GR) of 4 patients each: GR 1 (hemophan membrane, 35 BD), GR 2 (polyacrylonitrile, PAN AN 69, 42 BD), GR 3 (polysulphone, 38 BD) and GR 4 (polycarbonate, 37 BD). The TO has been detected with the transcutaneous oxygen pressure (Tc pO_{2 } ) using a transcutaneous oxymeter and the ED has been evaluated with the EMI …(Erythrocyte Morphometric Index), which results from the ratio between deformable erythrocytes (bowl shape) and rigid erythrocytes (discocyte shape), for every 100 red cells fixed in vitro with 0.3% glutaraldehyde. The ED was also evaluated using a laser instrument: Laser Optical Rotational Cell Analyser. During BD was observed a significant decrease of Tc pO_{2 } in the 1st hour only in the 1st and 2nd GR and, in contrast with results obtained in the 3rd and 4th GR, in the same GRs the EMI showed a significant reduction of ED at the end of BD. Finally the LORCA results, showing a significant decrease of ED only in the 1st and 2nd GR, confirmed the data obtained with EMI. In conclusion, our study has suggested that hemophan and PAN AN 69 are less biocompatible than polysulphone and polycarbonate membranes according to effects on ED and TO. Show more

Keywords: Dialysis membranes, biocompatibility, oxymetry, transcutaneous oxymetry, erythrocyte deformability

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 421-424, 1999

Authors: Izzo, P. | Spagnuolo, A. | Manicone, A. | Nazzaro, P. | Lauta, V.M.

Article Type: Research Article

Abstract: In this study we report results regarding erythrocytes deformability in congenital dyserythropoietic anemia type II (HEMPAS) by the use of LORCA (Laser‐assisted Optical Rotational Cell Analyzer). The reduced erythrocytes deformability observed in seven case of CDA II is caused by changes in the structure of glycoproteins due to the incomplete glycosylation of erythrocytic and erythroblastic membrane. Erythrocytes deformbility (EI) was shown to be inversely related with mean corpuscular volume (MCV) and mean haemoglobin concentration (MCH).

Keywords: Dyserythropioietic anaemia, LORCA, erythrocytes deformability

Citation: Clinical Hemorheology and Microcirculation, vol. 21, no. 3-4, pp. 425-430, 1999