Clinical Hemorheology and Microcirculation - Volume 35, issue 1-2

Authors: Kobayashi, Takao | Nakamura, Mashio | Sakuma, Masahito | Yamada, Norikazu | Sakon, Masato | Fujita, Satoru | Seo, Norimasa

Article Type: Research Article

Abstract: Incidence of venous thromboembolism (VTE), which had been considered a relatively rare disease in Japan, has been on the increase in recent years as eating habits have become more similar to those of the West. We have investigated the recent incidence data of perioperative pulmonary thromboembolism (PTE) in Japan and have established guidelines for the prevention of VTE. Recommended thromboprophylaxis is early ambulation for low risk group, elastic stocking (ES) or intermittent pneumatic compression (IPC) for moderate risk group, IPC or low dose unfractionated heparin (LDUH) for high risk group, and LDUH + IPC or LDUH + ES for highest …risk group. The management fee for PTE prophylaxis was established and covered by health insurance in April 2004. Surprisingly, the incidence of perioperative PTE decreased just after this guideline was issued. After accumulation of further evidence and application of pharmacological agents, such as low molecular weight heparin, we will establish the advanced guidelines in the future. Show more

Keywords: Venous thromboembolism, pulmonary thromboembolism, thromboprophylaxis, elastic stocking, intermittent pneumatic compression, heparin

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 257-259, 2006

Authors: Momtselidze, Nana | Mantskava, Maia | Mchedlishvili, George

Article Type: Research Article

Abstract: The aim of the present study was the comparative analysis of the role of specific hemorheological derangements in the pathogenesis of ischemic brain infarcts with and without diabetes mellitus. Blood plasma viscosity, as well as red blood cells (RBC) aggregability were quantitatively investigated in all patients during the study. Both of the above mentioned indices of hemorheological disorders were significantly higher in the patients with brain infarcts and diabetes mellitus as compared to the control and the group of ischemic brain infarcts without diabetes. During the ischemic stroke, blood plasma viscosity was increased by a mean of 9.2 per cent …in the first and by a mean of 17.6 per cent in the second group of patients. As to the erythrocyte aggregability index, it was changed considerably more – by a mean of 113.8 per cent during stroke without diabetes, while in the diabetic patients the RBC aggregability index was found to be increased by a mean of 147.3 per cent. Ischemic brain infarcts in patients with diabetes mellitus were associated with a significant increase of the patients' blood rheological disorders in all the investigated cases. Show more

Keywords: Erythrocyte aggregability, blood plasma viscosity, ischemic brain infarct with and without diabetes mellitus

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 261-264, 2006

Authors: Bolokadze, N. | Lobjanidze, I. | Momtselidze, N. | Shakarishvili, R. | Mchedlishvili, G.

Article Type: Research Article

Abstract: The aim of this work was to perform a comparative investigation of erythrocyte aggregability changes in the peripheral and cerebral circulation during ischemic and hemorrhagic stroke. Subjects of the present study were patients with ischemic brain infarcts (14 patients) and with hemorrhagic stroke (21 patients) from the Intensive Care Unit of the Institute of Neurology and Neurosurgery. The blood samples were obtained from the following blood vessels: the common carotid artery carrying blood to the primarily damaged brain hemisphere, both jugular veins carrying blood from the primarily damaged and the contralateral hemispheres, as well as from the cubital vein to …obtain specimens of the systemically circulating blood. Erythrocyte aggregation was evaluated by using the “Georgian technique”. We found that the RBC aggregation indices increased in both the regional as well as the systemic circulation of the hemorrhagic stroke patients as compared to ischemic stroke patients. The results of the present study demonstrate different changes of erythrocyte aggregation in ischemic and hemorrhagic stroke patients. Therefore, the role of blood rheological properties in their pathogenesis seems also to be different. Show more

Keywords: Erythrocyte aggregation, ischemic stroke, hemorrhagic stroke

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 265-267, 2006

Authors: Bianciardi, Giorgio | Tanganelli, Italo | Totagiancaspro, Dorotea | Brogi, Marco | Carducci, Antonietta | De Santi, Maria Margherita

Article Type: Research Article

Abstract: Fractal dimension of pericellular membrane of monocytes was evaluated in diabetic patients and in control subjects. Monocytes were collected from normal healthy volunteers (n=6) and from diabetic (type 1 and type 2) patients (n=9). Monocytes from healthy volunteers were also stimulated in vitro with the ionophore A23187 or with the oligopeptide FMLP. Monocytes, obtained by Ficoll-Hypaque, were examined with a Philips 300 transmission electron microscope. The cell contour was extracted, resized to a standard dimension and converted to a single pixel outline. Box-counting method was then applied to determine the fractal dimension. Fractal dimensions of monocytes appeared statistically increased in …diabetic patients (type 1 and type 2), compared with sex- and age-matched controls (p<0.01, p<0.01). The mechanism underlying the observed increased complexity of pericellular membrane may be explained by the in vivo activation of the circulating monocyte in diabetes. In effect, fractal analysis of stimulated in vitro monocytes showed a significant increase of complexity of pericellular membrane, compared with their controls (p<0.001). Our approach was able to assess and quantitatively evaluate in diabetic patients morphological modifications of the monocyte linked to its activation, offering new parameters useful to follow the effects of therapeutical procedures. Show more

Keywords: Fractals, morphometry, monocytes, diabetes

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 269-272, 2006

Authors: Fornal, Maria | Lekka, Małgorzata | Pyka-Fościak, Grażyna | Lebed, Kateryna | Grodzicki, Tomasz | Wizner, Barbara | Styczeń, Jan

Article Type: Research Article

Abstract: The mechanical properties of erythrocyte membrane have been studied using an atomic force microscope. Measurements were carried out on blood samples taken from 7 diabetes mellitus patients and 8 healthy individuals. For each blood sample a distribution of a Young's modulus was constructed. It has been found that both the mean value and the width of the distribution in diabetic patients exceed the corresponding results for healthy persons by a factor greater than 3. The high sensitivity of the atomic force microscopy and the ability to measure the full distribution of the erythrocyte membrane Young's modulus makes it a unique, …powerful and promising tool in studies of the membrane stiffness of red blood cells. Show more

Keywords: Atomic force microscopy, erythrocyte deformability, erythrocyte stiffness, diabetes mellitus

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 273-276, 2006

Authors: Riquelme, Bibiana | Foresto, Patricia | D'Arrigo, Mabel | Filippini, Fernando | Valverde, Juana

Article Type: Research Article

Abstract: Hypertension (HTA) and dyslipidemia (DLP) represent major risk factors for cardiovascular and cerebral-vascular ischemic disease. The mechanisms through which they can induce vascular damage are both metabolic and mechanical. Hemorheological alterations in HTA are result of changes affecting both red cell intrinsic structure and their interactions with the plasmatic components. Several hemorheological determinants (biochemical, ionic, metabolic and rheologic) could influence and produce an impaired erythrocyte deformability determining an increased flow resistance in the microcirculation. The “Erythrodeformeter” allows obtaining the stationary and dynamical linear parameters of erythrocyte membrane by laser diffractometry. Stationary and oscillatory shear-induced elongation of cells leads to an …elliptical diffraction pattern, its geometric characteristics being directly related to those of deformed RBC. Erythrocyte stationary parameters (Deformability Index, surface viscosity and elastic modulus) were obtained in stationary regime. Complex viscoelastic parameters (dynamic elasticity, dynamic loss, viscous and elastic components of the complex viscosity) were obtained when operating in oscillating mode. The diffractometric method is sensitive to detect pathological or induced alterations on RBC membrane, which can affect blood flow in vivo. The rheological parameters obtained give important information about the erythrocyte membrane and allow to detect and characterize erythrocyte alterations in vascular pathologies. Show more

Keywords: Diffractometry, erythrocyte viscoelastic properties, hemorheology, hypertension

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 277-281, 2006

Authors: Travagli, Valter | Zanardi, Iacopo | Boschi, Letizia | Turchetti, Vera | Forconi, Sandro

Article Type: Research Article

Abstract: Clinical measurement of blood viscosity is an important parameter in the diagnosis of different diseases (e.g., diabetes, hypertension, cardiovascular diseases). The significance of blood viscosity in the microcirculatory flow is also of great importance. Thus, a simple and accurate evaluation of hemorheological properties could be an important challenge in clinical practice. Nowadays, validated measurements of plasma viscosity are commonly carried out with rotational viscometers by means of the various geometric configurations. However, red blood cells deform under mechanical force and this aspect could lead to an artificial variation in the apparent viscosity. In this work, an evaluation of a new …technique for the viscosity determination is focused. In particular, a torsional oscillation viscometer was adopted (VM10AL, CBC Europe) in the presence and in the absence of stirring conditions at thermostated conditions. The profile of the rheological behaviour as a function of time was recorded and compared with that obtained using a cone-plate rotational viscometer (AR300, TA Instrument). Show more

Keywords: Blood viscosity, torsional oscillation viscometer

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 283-289, 2006

Authors: Athanassiou, G. | Moutzouri, A. | Kourakli, A. | Zoumbos, N.

Article Type: Research Article

Abstract: Sickle cell disease is characterized by vaso-occlusive episodes, mainly in the small vessels, resulting in tissue ischemia, multi-organ failure, and, occasionally, death. Hydroxyurea (HU) is an agent with important and effective role in the treatment of patients suffering from this disease. The purpose of this study was to estimate the effect of HU on the deformability of the red blood cell's membrane (RBCM) in an effort to possibly improve the rheological properties of the RBCs of patients with sickle cell anemia (SCA), as well as to investigate the mechanical and rheological properties of these cells using micropipette and filtration techniques. …The rigidity index, IR, which is a measure of cell rigidity and the elastic shear modulus, μ, which is a measure of cell's membrane deformability (CMd), of the RBCs from normal subjects, used as normal controls, were found significantly lower as compared to those of patients with SCA, regardless the treatment with HU. Patients under treatment with HU exhibited values better than those of untreated patients, in both, IR as well as μ, although still worse than the values of normal controls. Show more

Keywords: Red blood cell deformability, filterability, sickle cell disease, micropipette

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 291-295, 2006

Authors: Aydoğan, Sami | Yerer, Mükerrem Betül | Çomu, Faruk Metin | Arslan, Mustafa | Güneş-Ekinci, Işın | Unal, Yusuf | Kurtipek, Omer

Article Type: Research Article

Abstract: Alterations in blood rheology under the influence of anesthesia have been observed and discussed among the responsible factors for the deterioration of tissue and organ perfusion related to anesthetic procedures. Sevoflurane is one of the volatil anesthetics which is being used very common in surgery. In this study, the effects of sevoflurane anesthesia were investigated in different age groups of rats. 22 male rats were used in the study and the rats were divided into two groups according to their age (young and old) comprising of two subgroups in each. First group was the young control (n=5), the second was …the young group treated with sevoflurane (n=5), the third group was the old control (n=7) and the last group was the old group treated with sevoflurane (n=5). %2 of sevoflurane was applied to the rats with inhalation in a adjustable cage for one hour. The deformability indexes of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD). Deformability indexes of red blood cells were significantly decreased with sevoflurane in old rats (p=0.028) whereas it had not any significant effect in young group compared with their controls. When we compared the young and old control groups, the deformability indexes were significantly higher in old ones (p<0.001). However, there were not any significant difference between the old and the young sevoflurane applied groups. A volatil anesthetic agent sevoflurane has impaired the deformability of erythrocytes in old rats compared to their controls, whereas it had not any significant effect in young ones which may be due to the flexibility of the young erythrocytes leading them to tolerate to the environmental changes. These results reveal that the inhalation anesthetics like sevoflurane may cause more serious problems in the elder people and their hemodynamic parameters should be checked more seriously during the surgery. Show more

Keywords: Sevoflurane, erythrocyte deformability, anesthesia, rat

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 297-300, 2006

Authors: Musielak, Malgorzata | Kościelak, Jerzy

Article Type: Research Article

Abstract: Human fibrinogen (TF) has been separated into two fractions: F1 – homodimers with respect to the γ chain, and F2 – heterodimers composed of γA and γ′ polypeptides. Their rouleaux-inducing properties were as follows: (1) both, at the same concentration of 0.8%, were less effective than TF; (2) F1 produced larger rouleaux even under static conditions of a hemocytometer where F2 was silent; (3) F2 induced the process when a suspension was gently sheared between microscopic slides. Since the synthetic peptide γ′(414–427) inhibited the rouleau formation in a mixture with F2, the C-terminal amino acids of the γ′ polypeptide …probably bind the molecule to the cell. The inhibition was feebly visible in the native ratio of F1/F2, implicating a compensatory effect of F1. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 301-303, 2006