Clinical Hemorheology and Microcirculation - Volume 36, issue 2

Authors: Ferrero, Mariana | Crosetti, Diego | Dominighini, Alicia | de Luján Alvarez, María | Ronco, María Teresa | Wagner, Marcelo L. | Gurni, Alberto | Carnovale, Cristina | Luquita, Alejandra

Article Type: Research Article

Abstract: Ligaria cuneifolia (R et P) Tiegh. (Loranthaceae) (Lc) aqueous extract-treated rats by via intraperitoneal (i.p.) show increased blood viscosity and decreased plasma cholesterol (Chol) levels. In this work, we analize the effect of the vehicle polyvinylpyrrolidone (PVP) and that of the Methanolic Fraction of the extract of Lc (MFLc) on hemorrheological properties in vivo and in vitro and on biliary excretion. For in vivo conditions, adult male Wistar rats were divided in five experimental groups (n=5 each one) which were injected, every 24 hr during 3 days by via i.p., with: (1) saline solution (Control); (2) PVP 0.47 mg/100 g …bw; (3) MFLc 0.95 mg/100 g bw plus PVP 0.47 mg/100 g bw; (4) PVP 12.5 mg/100 g bw; and (5) MFLc 23.0 mg/100 g bw plus PVP 12.5 mg/100 g bw. Intended for in vitro conditions, blood samples obtained by heart puncture were divided into three fractions, which were incubated with: saline solution (Control), PVP 12.5 mg%, and MFLc 25 mg% plus PVP 12.5 mg%. We demonstrated a direct effect of PVP alone and of MFLc “per se” on the erythrocyte membrane resulting in a cell shape change from dyscocyte to spherostomatocyte (MI more negative) as well as a decrease in erythrocyte deformability (increased RI). These changes induce an increase in blood viscosity. Decreased plasma Chol is a consequence of an increased bile salts biliary excretion. Show more

Keywords: Ligaria cuneifolia, whole blood viscosity, plasma cholesterol, erythrocyte deformability, biliary excretion, polyvinylpyrrolidone

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 95-104, 2007

Authors: Spengler, M.I. | Leroux, M.B. | Svetaz, M.J. | Contesti, J.F. | Parente, F.M. | Bertoluzzo, S.M.

Article Type: Research Article

Abstract: Systemic scleroderma is an autoimmune disease, due to a connective tissue alteration characterized by extracellular matrix increase in the skin and internal organs. It is already known that the Raynaud's phenomenon and the microcapillary obliteration lead to ischemia and peripheral tissue injury. The ischemia–reperfusion phenomenon releases free radicals, that react with red blood cells (RBCs) membrane components originating lipid peroxidation and impairment of the ATP-Ca++ pump, two possible mechanisms responsible of disease pathogenesis. Nifedipine is a Ca++ -channel antagonist that has been used for a long time in Raynaud's phenomenon treatment. In the present study we were able to …demonstrate that erythrocyte deformability and two other related variables such as membrane fluidity and osmotic fragility improve significantly with nifedipine therapy. It is likely that nifedipine inhibiting cytoplasmic calcium accumulation could restore some red blood cell membrane properties. Show more

Keywords: Systemic scleroderma, nifedipine, erythrocyte deformability, membrane erythrocyte fluidity, osmotic fragility

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 105-110, 2007

Authors: Goldin, Y. | Tulshinski, T. | Arbel, Y. | Rogowski, O. | Ami, R. Ben | Serov, J. | Halperin, P. | Shapira, I. | Berliner, S.

Article Type: Research Article

Abstract: The aim of the present study was to explore the difference between viral and bacterial infections regarding the intensity of erythrocyte aggregation in the peripheral venous blood. Although a rheodifference in terms of erythrocyte aggregation between viral and bacterial infections has been shown by us in the past, the time from onset of disease was not included. We have presently included the time from the onset of disease in a group of 133 patients with an acute bacterial infection who showed a significantly enhanced erythrocyte aggregation as opposed to a group of 23 with viral ones and no increased erythrocyte …aggregation despite of there being no significant difference in the time from onset of disease (55.7±55.6 hours in the bacterial group versus 50±35.2 in the viral one). In addition, we could match 22 patients with viral infections who presented the same fibrinogen concentrations (338±78 mg/dl) as those with acute bacterial ones (338±79 mg/dl). Although of borderline (p=0.06) significance, patients with an acute bacterial infection presented enhanced (vacuum radius=12.6±6.4 microns) erythrocyte aggregation as opposed to their isofibrinogenemic counterparts (vacuum radius=9.4±6.5 microns). Again, both groups presented no difference regarding the time from onset of disease. We conclude therefore that patients with acute bacterial infections present higher levels of erythrocyte aggregation. This is not a result of a shorter time interval from disease onset of the viral group. The known detrimental effects of increased erythrocyte aggregation regarding capillary slow flow, endothelial dysfunction and reduced tissue oxygenation might be therefore relevant in the context of patients with an acute infection, especially the bacterial ones. Show more

Keywords: Erythrocyte aggregation, acute infections

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 111-119, 2007

Authors: Pribush, A. | Hatzkelson, L. | Meyerstein, D. | Meyerstein, N.

Article Type: Research Article

Abstract: Red blood cell (RBC) aggregation in blood samples taken from healthy volunteers and from multiple myeloma (MM), iron deficiency (IDA) and β-minor thalassemia (T) patients was studied by a novel method based on electrical properties of colloidal systems. It was found that RBC aggregation changes in the following order: MM > IDA > control ≥ T. Comparison of aggregation data obtained by this and other techniques shows that the sensitivity of the proposed technique to detect abnormal changes in RBC aggregation is substantially higher. For example, the mean values of relative aggregation indices measured for MM by this method and …that based on the phenomenon of light scattering are 13.0 and 4.2, respectively. The high sensitivity of this technique allows investigations of the effect of moderate aggregating agents (i.e., IgG) on RBC aggregation. It is assumed that the higher sensitivity of the proposed technique to abnormal changes in RBC aggregation may be helpful both in basic studies to improve the understanding of the reason(s) for these abnormal changes, and in clinical investigations for earlier diagnostics. Show more

Keywords: Erythrocyte, aggregation, multiple myeloma, iron deficiency, thalassemia

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 121-132, 2007

Authors: Rasia, M. | Spengler, M.I. | Palma, S. | Manzo, R. | Lo Nostro, P. | Allemandi, D.

Article Type: Research Article

Abstract: 6-O-alkyl ascorbic acid esters (ASCn) are amphiphilic molecules that behave as surfactants in aqueous solution. These compounds show physico-chemical and aggregation properties that depend on the alkyl chain length, pH and temperature. It must consider that ASCn have shown some physical and rheological properties that suggest a potential utility as drug carriers. The present paper aims to evaluate the effects of these surfactants on human erythrocyte membranes. The membrane properties studied were: osmotic resistance in hypotonic media, shape transformation, and vesicle release at lytic concentration. According to our results, all properties depended on the length of the hydrophobic chain and …they did not evolve monotonically. Finally, the study of ASCn interaction with erythrocyte membrane allowed us to postulate the crucial influence that the molecular structure exerts upon the manner in which amphiphiles interact with biological membranes and the effects involved in them. Show more

Keywords: Amphiphiles, ascorbic acid esters, cell membrane, hypotonic haemolysis, membrane curvature, vesiculation

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 133-140, 2007

Authors: Clevert, D.-A. | Jung, E.M. | Johnson, T. | Kubale, R. | Rupp, N. | Schoenberg, S.O. | Reiser, M.

Article Type: Research Article

Abstract: Objective: The objective of this study was to evaluate the efficiency of B-Flow ultrasound in diagnosing supraaortic vessel dissections compared with other ultrasound techniques including B scan, Color-Coded Doppler (CCDS) and Power Doppler (PD). Materials and methods: Eighty-eight patients with suspected arterial dissection of the neck vessels were included in this prospective trial. All patients were examined using B scan, Color-Coded Doppler sonography and Power Doppler. After documentation of the diagnoses, the patients were additionally examined by B-Flow ultrasound. Contrast-enhanced magnetic resonance angiography (MRA) was used as reference standard in all cases. Results: Dissections of the carotid artery (n=19) and …of the vertebral artery (n=35) were found in 44 patients. B-Flow imaging identified 52 of 54 arterial dissections that were confirmed by MRA. There were no false-positive diagnoses in ultrasound examination. The sensitivity of ultrasound examination using B scan, CCDS and PD in detecting all dissections was 95.9% and 99.1% with additional B-Flow examination. Sensitivity using B-Flow increased from 98.3% to 100% for carotid dissections and from 93.3% to 94.3% for vertebral artery dissections. Due to the lack of overwriting artifacts, B-Flow imaging detected residual flow within the false lumen more precisely. The reduced effect of the ultrasound probe angle facilitated imaging of fissures, membranes and low flow phenomena and improved the identification of low-reflection wall structures. The cine mode of the B-Flow showed undulating membrane movement most clearly. Contrast-enhanced MRA in conjunction with axial T1 and T2 weighted sequences enabled the best visualization of intramural hematomas. Conclusion: B-Flow imaging can significantly increase the sensitivity of ultrasound examination for dissections of the neck vessels. It also improves the visualization of flow within the true and false lumen, of hypoechoic thrombi and of intramural hematoma. Show more

Keywords: B-Flow imaging, carotid artery, vertebral artery

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 141-153, 2007

Authors: Sagesaka, Toshiaki | Juen, Hiroyasu | Hayashi, Masatoshi

Article Type: Research Article

Abstract: The influence of a change in red blood cell (RBC) concentration on the initiation time of blood coagulation (Ti) in pregnant and non-pregnant females was investigated using a damped oscillation rheometer to evaluate the risk of hemorrhagic tendency or thrombus formation. The blood samples from 40 female volunteers (20 pregnants and 20 non-pregnants) were examined. After centrifuging some portion of each blood sample, an appropriate volume was taken from the RBC layer to make an artificially diluted blood, or to add it to the autologous blood, making an artificially concentrated blood. The Ti of non-pregnant females was significantly reduced with …increasing the RBC concentration from 3.75±0.25 to (5.75±0.25)×106 /mm3 . However, the Ti of pregnant females showed almost no change in the RBC concentrations from 3.25±0.25 to (5.25±0.25)×106 /mm3 . These results suggest that RBC concentration plays an important role in accelerating the initial coagulation reaction of blood of non-pregnant females and that a hypercoagulant condition caused by pregnancy conceals the effect that changes in RBC concentration have in pregnant females. Show more

Keywords: Anemia, blood coagulation, damped oscillation rheometer, pregnancy, thrombus formation

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 155-161, 2007

Authors: Rossi, M. | Carpi, A. | Di Maria, C. | Galetta, F. | Santoro, G.

Article Type: Research Article

Abstract: The aim of the study was to investigate whether chronic cigarette smoke habit is associated with changes of laser Doppler (LD) skin blood flowmotion (SBF). We performed spectral analysis of skin forearm LD signal detected by a LD flowmetry (Periflux PF4, Perimed, Sweden) before and during forearm post-ischemic hyperaemia, in 14 healthy chronic smoker subjects and 14 age and sex matched nonsmoker subjects. Forearm skin ischemia was obtained by a pneumatic cuff, positioned at the right arm and inflated for 3 minutes to 30 mmHg above systolic blood pressure. Power spectral density (PSD) of the SBF total spectrum (0.009–1.6 Hz), …as well as 0.009–0.02 Hz , 0.02–0.06 Hz, 0.06–0.2 Hz, 0.2–0.6 Hz and 0.6–1.6 Hz frequency intervals (FI), referred to endothelial, sympathetic, myogenic, respiratory and heart activity, respectively, were measured in LD conventional perfusion units (PU)/Hz. Smokers showed a basal SBF total spectrum PSD mean values not significantly different from nonsmokers (2.14±1.58 PU/Hz and 1.93±1.35 PU/Hz, respectively). Following ischemia, PSD mean value of SBF total spectrum, as well of five FI considered, significantly increased in nonsmokers (p<0.01), while it did not significantly change in smokers. Smokers and nonsmokers did not differ in basal and post-ischemic skin LD perfusion mean values. The absent post-ischemic increase of the SBF and of its FI related to endothelial and myogenic activity in smokers can be an early sign of skin microcirculatory impairment, suggesting an endothelial and smooth muscle skin microvascular dysfunction associated with the chronic smoking habit. Show more

Keywords: Chronic cigarette smoking habit, skin blood flowmotion, skin post-ischemic hyperemia, laser Doppler flowmeter

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 163-171, 2007

Authors: Toyama, Yoshiharu | Pais, Eszter | Meiselman, Herbert J. | Alexy, Tamas

Article Type: Research Article

Abstract: Cyclic oligomers of glucose, termed cyclodextrins (CDs), can contain 6 (α-CD), 7 (β-CD) or 8 (γ-CD) glucose units and are able to remove cholesterol from platelet membranes and decrease platelet aggregation. The present study was designed to examine the effects of these CDs on RBC aggregation and blood viscosity. Blood from normal adult volunteers was incubated at 37°C with 3.0×10−4 to 1.5 mM levels of the CDs, then processed to obtain platelet-rich plasma, platelet poor plasma and 40% hematocrit blood; measurements included collagen-induced platelet aggregation, RBC aggregation (Myrenne Aggregometer) and blood viscosity at 1–1000 sec−1 (Rheolog® ). Our results …indicate the expected dose-dependent inhibition of platelet aggregation by β-CD, with no significant effects of α-CD or γ-CD. RBC aggregation studies showed no effect of α-CD but highly significant (p<0.01) decreases by both β-CD and γ-CD; at the concentrations studied (1.5×10−3 to 1.5 mM), β-CD had somewhat greater effects. Blood viscosity was not affected by α-CD, but was significantly decreased in a dose-dependent manner by β-CD and, at the highest concentration (1.5 mM), by γ-CD. Interestingly, the effects of β-CD and γ-CD were independent of shear, with these effects not explained by the usual mechanisms. These results suggest the potential hemorheological value of CDs, yet also indicate the need for additional studies. Show more

Keywords: Cyclodextrins, hemorheology, red blood cell, aggregation, platelets

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 173-180, 2007

Authors: Feher, Gergely | Koltai, Katalin | Toth, Kalman

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 36, no. 2, pp. 181-182, 2007