Clinical Hemorheology and Microcirculation - Volume 30, issue 2

Authors: Yerer, M. Betul | Yapislar, Hande | Aydogan, Sami | Yalcin, Ozlem | Baskurt, Oguz

Article Type: Research Article

Abstract: Sepsis has been associated with a lipopolysaccharide (LPS) induced bacterial infection and causes biochemical, hemodynamic and physiological alterations in a system. Erythrocyte deformability is very critical for a microcirculatory system to function effectively. Hence, we were interested in examining the effects of a potent antioxidant, melatonin (Mel), on lipid peroxidation and deformability of eythrocytes in LPS‐induced experimental sepsis. Male Swiss Albino rats were used in 6 groups, each group comprising of 10 animals. The first group was the control, and the other groups were administered LPS (10 mg/kg, i.p.), Mel (10 mg/kg, i.p.), LPS + L‐NAME (5 mM, i.p.), Mel …+ LPS and Mel + LPS + L‐NAME, respectively. Deformability of the RBCs decreased significantly (p<0.05) in the LPS group in comparison to all other groups. This reduction was prevented with both L‐NAME and Mel, but was not as significant as when administering L‐NAME or Mel alone. This result was adversely seen in nitric oxide levels, i.e. RBCD was reduced when the NO levels were higher. Therefore in the Mel group the NO levels were reduced while the RBCD enhanced. In addition to these, as an index of lipid peroxidation, the Malondialdehyde levels were elevated in LPS groups whereas the deformability was reduced. This lipid peroxidation was suppressed by Mel and/or L‐NAME significantly, where the RBCD was enhanced. These results show that, Melatonin can elevate the RBCD in experimental sepsis due to its nitric oxide scavenging activity and antioxidant effect as revealed by lipid peroxidation. Show more

Keywords: Erythrocyte deformability, melatonin, sepsis, lipid peroxidation, rats

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 77-82, 2004

Authors: Thurston, George B. | Henderson, Nancy M. | Jeng, Michael

Article Type: Research Article

Abstract: Red blood cells containing hemoglobin S are less deformable than normal erythrocytes and have a major effect on the viscoelasticity of blood. This alteration in rheology increases the impedance to flow, leading to an increase in RBC aggregation and reduction in oxygen saturation, which induces further sickling and occlusions in the microcirculation. Patients with sickle cell disease (SCD) can experience severe complications, such as acute pain and stroke. Automated red blood cell exchange transfusion, or erythrocytapheresis, is used with homozygous SCD (Hb SS) to replace sickled cells with normal cells, thereby decreasing the percentage of sickle hemoglobin (%Hb S) and …maintaining a net balance in iron accumulation. These patients received monthly erythrocytapheresis with a goal to maintain a pre‐pheresis %Hb S at less than 30%. In this study, viscoelastic parameters were used to quantify the effectiveness of this therapy for six patients undergoing chronic erythrocytapheresis. Whole blood viscosity, elasticity and relaxation time at oscillatory strains of 0.2, 1 and 5, and hematocrit and %Hb S were measured prior to erythrocytapheresis and 15 minutes after completion and compared with normal reference values at the patient's hematocrit. This study confirms the beneficial effects on viscosity, elasticity, and relaxation time of erythrocytapheresis. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 83-97, 2004

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

Article Type: Research Article

Abstract: The present study was aimed at investigating the red blood cell (RBC) aggregation and the parameters of lipid peroxidation – malondialdehyde (MDA) and MDA + 4‐hydroxyalkenals (HAE) – in the blood of critically deteriorated stroke patients (brain infarcts, parenchymatous and subarachnoid hemorrhages) and in the control group. Measurements were made in blood samples from the common carotid artery, the both internal jugular and cubital veins. The RBC aggregation index was found to increase by about 80 per cent in both the cerebral and systemic circulation as compared to the control blood samples. MDA content appeared also significantly higher in the …blood flowing out of the damaged hemisphere of the neurocritical patients as compared to the control group. In the blood flowing out of the damaged hemisphere of the neurocritical patients MDA as well as MDA + HAE content significantly exceeded the values found in blood samples of the jugular vein of the contralateral hemisphere, carotid artery and the cubital vein. The results of this study suggest a certain interdependence between the blood plasma lipid peroxidation and the RBC aggregation in the brain vessels following its damage. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 99-105, 2004

Authors: Alt, Elisabeth | Amann‐Vesti, Beatrice R. | Madl, Christian | Funk, Georg | Koppensteiner, Renate

Article Type: Research Article

Abstract: Abnormalities in blood rheology and platelet dysfunction might play a role in the pathogenesis of multiple organ failure in septic patients by reducing microvascular blood flow. To determine whether alterations in blood rheology and in platelet function are related to the severity of organ dysfunction, we prospectively studied plasma fibrinogen, red cell aggregation, plasma viscosity, hematocrit, whole blood viscosity and platelet aggregation in relation to the Sepsis‐related Organ Failure Assessment (SOFA) score in 34 consecutive patients with severe sepsis/septic shock. We found that patients had higher plasma fibrinogen, red cell aggregation and plasma viscosity (p<0.01), but lower hematocrit, whole blood …viscosity and ADP‐induced platelet aggregation than controls (p<0.01). Platelet aggregation (p<0.01), but not other rheological variables, were inversely related to the SOFA score. Only platelet count was linked to poor clinical outcome (p<0.05). We conclude that blood rheology and platelet function are severely altered in patients with severe sepsis/septic shock. Our findings suggest progressive platelet dysfunction with advancing severity of the disease. Platelet dysfunction might play a more important role in the pathogenesis of the multi organ dysfunction syndrome than abnormalities in blood rheology. Show more

Keywords: Sepsis, platelet aggregation, blood rheology, SOFA score

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 107-115, 2004

Authors: Sun, Dagong | Wang, Jinhua | Yao, Weijuan | Gu, Li | Wen, Zongyao | Shu, Chien

Article Type: Research Article

Abstract: Mutant p53 gene and wild‐type p53 gene were introduced into murine erythroleukemia cell line (MEL). The MEL cells transfected with mutant p53 gene (MEL‐M) and with wild‐type p53 gene (MEL‐W) were obtained by G418 selection. MEL, MEL‐W and MEL‐M were injected intraperitoneally into BALB/C mice. In the first week after injection, the signs of erythroleukemia were induced in all three groups. Abnormalities were mainly found in the spleen, bone marrow, liver and peripheral blood. There was an increase of proerythroblasts in the bone marrow. A large amount of normoblasts (early and intermediate erythroblasts) appeared in the spleen. In the peripheral …blood, the white blood cells, reticulocyte and platelet counts increased and RBC count and hematocrit decreased. The degree of abnormalities in the MEL‐W group was significantly lower than that in other two groups. Hemorheological measurements indicated that the deformability and orientation of RBCs in MEL and MEL‐M groups were impaired, whereas those in MEL‐W group did not change significantly. Micropipette aspiration measurement revealed that MEL‐W had higher elastic modulus than MEL and MEL‐M, indicating that it was more difficult for MEL‐W to deform and migrate in vivo. The results of animal test and micropipette suggest that exogenous wild‐type p53 gene could reduce the tumorigenesis of murine erythroleukemia cells. Show more

Keywords: p53 gene, murine erythroleukemia cells, tumorigenesis, gene transfection

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 117-126, 2004

Authors: Pepple, D.J. | Mullings, A.M. | Reid, H.L.

Article Type: Research Article

Abstract: Hyperviscosity of the maternal blood has been reported to be associated with an increased incidence of adverse perinatal outcome in preeclampsia. We related the changes in maternal blood viscosity to perinatal outcome in 47 preeclamptic, nulliparous, black Jamaican women. A group of 49 non‐preeclamptic, nulliparous, gestation‐matched women acted as controls. Perinatal outcome was also compared between the women with high blood viscosity (≥5 mPa.s) and those with low blood viscosity (<5 mPa.s) in both the preeclamptic and non‐preeclamptic groups. Data was analysed by the comparison of two proportions, the chi‐squared test, the Fisher's exact test and the Pearson's correlation method. …The level of statistical significance was taken at p<0.05. The incidence of adverse perinatal outcome was significantly (p<0.001) higher in the preeclamptic women as compared with that of the non‐preeclamptic controls. However, of interest, was the fact that within the preeclamptic group, the incidence of adverse perinatal outcome was significantly (p=0.001, Fisher's exact test) higher in those with low blood viscosity as compared with those with high blood viscosity. These results suggest that low maternal blood viscosity may be related to increased incidence of adverse perinatal outcome in Jamaican women with preeclampsia. Show more

Keywords: Maternal blood viscosity, perinatal outcome, preeclampsia

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 127-131, 2004

Authors: Nemeth, N. | Szokoly, M. | Acs, G. | Brath, E. | Lesznyak, T. | Furka, I. | Miko, I.

Article Type: Research Article

Abstract: We have studied systemic and regional changes in hemorheological parameters after complete acute limb ischemia and reperfusion (I/R) in 24 mongrel dogs. Unilateral cooled and non‐cooled vascular ischemia (3 h)–reperfusion (4 h), and sham‐operations were performed. Blood samples were collected from the excluded region, during reperfusion and for 5 days. Whole blood and plasma viscosity (WBV, PV), relative cell transit time (RCTT) of erythrocytes, fibrinogen level and hematological parameters were determined. In I/R groups WBV of excluded blood was significantly higher compared to the base (p<0.05), and RCTT increased during the reperfusion. On 2nd–3rd days RCTT increased significantly in both …I/R groups. In each group PV and fibrinogen showed continuous increase during the postoperative period, prominently in cooled I/R group, and furthermore WBV corrected for hematocrit (40%) was the highest in cooled I/R group. These suggest that surgical acute limb I/R may cause hemorheological changes, which are more serious after cooling. (Grants: OTKA‐T032571, 6003/1/2001/ETT.) Show more

Keywords: Canine limb ischemia–reperfusion, cooling, hemorheology

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 2, pp. 133-145, 2004