Clinical Hemorheology and Microcirculation - Volume 45, issue 2-4

Authors: Zvetkova, Elissaveta | Antonova, Nadia | Ivanov, Ivan | Savov, Yonko | Gluhcheva, Yordanka

Article Type: Research Article

Abstract: Hemorheological abnormalities such as elevated whole blood viscosity, plasma viscosity, erythrocyte deformability and platelet aggregation, hematocrit and fibrinogen levels, are frequently examined as diagnostic tool and prognostic relevance in socially important hemorheological disorders. Distinct biological – morphological and functional platelet alterations, have been described in different addictions (heroin-, cocaine-, nicotine-, alcohol-, etc.). Chronic addictions could cause biochemical and conformational changes in platelets and their membranes, thus modulating platelet receptor expression, morphology (anisocytosis, giant platelets) and activation (alpha-granule release), platelet aggregation and hemorheological properties. Some of these alterations in chronic addicts – documented at cellular- and molecular level, could be easily …used as a precise diagnostic tool with regard to thromboembolic complications and microcirulation injuries attributable to addictions. The present review focuses on some changes in platelet morphological, functional and rheological properties induced by chronic opiate/opioid abuse. Hypothesis is accumulated that free fatty acids (FFAs) and especially oleic acid (OA) could cause positive molecular and conformational changes in platelets of addicts with hemorheological disorders. Show more

Keywords: Addictions, platelets, hemorheology, platelet membrane fatty acids (PMFAs), oleic acid (OA)

DOI: 10.3233/CH-2010-1305

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 245-251, 2010

Authors: Antonova, N. | Riha, P. | Ivanov, I.

Article Type: Research Article

Abstract: Mechanical and electrical properties of red blood cells (RBC) suspensions in dextran 70 (Dx70), dextran 150 (Dx150), dextran 500 (Dx500) and polyethileneglycol (PEG) 35 000 with different concentrations were evaluated through apparent viscosity and conductivity measurements under steady and unsteady flow conditions. RBCs suspensions of the washed RBS in PBS (control) and Dx70, Dx150, Dx500 and PEG in PBS with different concentrations, adjusted to the same hematocrit of 40% were used for the experiments. Conductivity time and shear rate dependences in parallel with the rheological properties of the samples were studied under transient flow regimes at different local structure of …the uniform Couette flow. Their relationships on dextrans and PEG concentrations were evaluated too. Low shear viscosity increased and conductivity decreased of RBC suspensions, compared to non-aggregating suspensions, depending on dextrans and PEG concentrations. A time course of blood conductivity recorded under different flow conditions provides experimental description of RBC aggregation-disaggregation processes and other cell-cell interactions. The results show that the blood conductivity is strongly dependent on the considered blood factors and is influenced by flow, shear rates and concentration of dextran and PEG solutions. Show more

Keywords: Apparent viscosity, conductivity, unsteady flow, RBC suspensions, dextrans, PEG

DOI: 10.3233/CH-2010-1310

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 253-261, 2010

Authors: Nemeth, Norbert | Kiss, Ferenc | Furka, Istvan | Miko, Iren

Article Type: Research Article

Abstract: Although growing number of evidences supports the gender differences of hemorheological variables in human, little is known about this question in experimental animals. Investigating this question and giving laboratory-specific reference values, blood samples from healthy male and female CD rats and beagle dogs were tested for hematological parameters (microcell counter), blood and plasma viscosity (capillary viscometer), erythrocyte deformability (bulk filtrometry and ektacytometry), erythrocyte aggregation (light transmission aggregometer) and fibrinogen concentration (coagulometer). Besides the inter-species alterations we found hematological gender differences too regarding the red blood cell count and hematocrit. In rats the erythrocyte aggregation index was higher in females, …while in beagle dogs the males showed significantly higher aggregation index values. In rats the red blood cell deformability showed better values in females. In beagle dogs this was the opposite, the males had better elongation index (EI) values in the function of shear stress (SS). Besides this it was also experienced that the shape of the canine EI – SS curves differed from the rats’ values. Gender differences with inter-species alterations can be observed in laboratory animals (rats and dogs) that have to be taken under consideration during planning experiments and evaluating results. Show more

Keywords: Blood viscosity, plasma viscosity, red blood cell aggregation, red blood cell deformability, gender differences, laboratory animals

DOI: 10.3233/CH-2010-1303

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 263-272, 2010

Authors: Kiss, Ferenc | Nemeth, Norbert | Sajtos, Erika | Brath, Endre | Peto, Katalin | Baskurt, Oguz K. | Furka, Istvan | Miko, Iren

Article Type: Research Article

Abstract: Using “Furka’s spleen-chip” autotransplantation technique, in a follow-up study we investigated erythrocyte aggregation and its influencing factors regarding to asplenic-hyposplenic conditions. Healthy beagle dogs were equally divided into 4 groups: “Sham”- sham operated control, “SE”-splenectomy, “AU-5” and “AU-10”-autotransplantation with 5 or 10 spleen chips by Furka-method after splenectomy. Blood sampling for current investigation occurred on the 12th, 18th, 20th and 24th postoperative months, besides comprehensive structural and functional examinations. In this study we focused on the aggregation properties of erythrocytes in native samples and of density separated “young” versus “old” erythrocytes (Myrenne MA-1 aggregometer). Fibrinogen concentration (Sysmex CA-500 coagulometer) and …erythrocyte sedimentation rate (ESR) were also determined. SE group showed significantly elevated ratio of “old” and “young” erythrocyte aggregation index values on the 20th and 24th postoperative months (1.5 and 2.16, respectively) comparing to the AU (1.14 and 1.05) and Sham groups (1.2 and 1.27). In SE group fibrinogen concentration was mildly higher and ESR almost doubled versus control. The greater differences experienced between “young” and “old” erythrocytes may reflect decreased splenic filtration function. Consequently, the comparison of aggregation and deformability properties of “young” and “old” erythrocytes may give important information about the function of the spleen. Show more

Keywords: Splenic function, splenectomy, spleen autotransplantation, red blood cell aggregation, erythrocyte sedimentation rate

DOI: 10.3233/CH-2010-1304

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 273-280, 2010

Authors: Miko, Iren | Nemeth, Norbert | Sajtos, Erika | Brath, Endre | Peto, Katalin | Furka, Andrea | Szabo, Gyorgyi | Kiss, Ferenc | Imre, Sandor | Furka, Istvan

Article Type: Research Article

Abstract: Erythrocyte deformability could be a suitable parameter reflecting hyposplenic-asplenic conditions after splenectomy or spleen autotransplantation. The aim of this study was to analyze the efficacy of spleen autotransplantation using filtrometry and ektacytometry for testing erythrocyte deformability, besides complex structural, functional, hematological, hemostaseological and immunological examinations. Healthy beagle dogs were subjected to the study in the following experimental groups: “Sham”-sham operated control, “SE”-splenectomy, “AU-5” and “AU-10”-autotransplantation with 5 or 10 spleen chips using “Furka’s spleen chip” technique after splenectomy. Blood samples were taken before the operations and monthly afterwards for 1 year and bi-monthly till the end of the 2nd postoperative …year. Erythrocyte deformability was measured by bulk filtrometry (relative cell transit time, RCTT) and on the 20th–24th postoperative months by ektacytometry (elongation index, EI), too. RCTT was elevated in operated groups till the 12th month. On the 20th/24th months “SE”-group expressed the highest level, while the “AU”-groups were close to “Sham”-group. Using ektacytometer we found that on the 20th/24th month both EImax and SS1/2 showed the lowest values (because of unusual curve characteristic) in “SE”-group and “AU”-groups almost reached the “SH”-group. Spleen autotransplantation partially restored the normal rheological conditions. Both filtrometry and ektacytometry was suitable to investigate hyposplenic-asplenic conditions. Show more

Keywords: Splenectomy, spleen autotransplantation, Furka’s spleen chip technique, red blood cell deformability, sepsis

DOI: 10.3233/CH-2010-1307

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 281-288, 2010

Authors: Sajtos, Erika | Nemeth, Norbert | Kiss, Ferenc | Brath, Endre | Peto, Katalin | Hever, Timea | Matyas, Lili | Furka, Istvan | Miko, Iren

Article Type: Research Article

Abstract: Clinical studied showed leukocyte antisedimentation rate (LAR) changes in various conditions that modulate the immune system. There is a lack of LAR data in animal experiments concerning splenic function after splenectomy or spleen preserving operations, thus we aimed to include LAR in our ongoing inbred canine study on following-up spleen salvaging surgical techniques. Blood samples of healthy beagle dogs served as normal control. The experimental groups were: “SH”-sham operated, “SE”-splenectomy, “R1/3” and “R2/3”-one-third/two-third of the spleen resected, “AU-5” and “AU-10”-autotransplantation with 5/10 spleen chips using Furka’s techniques. On the 12th postoperative month Rabigen-Mono+Vanguard-Plus-5 vaccines were given to the animals, which …provoked immune response. Blood samples were taken before and one week after the vaccination. LAR was calculated by Bogar’s method. In normal control group LAR was 3.11, leukocyte count was 12.04 G/l. In the experimental groups LAR varied between 2.4–7.3 before vaccination. After vaccination LAR increased in all groups. Although “SE” group expressed the largest changes (LAR = 16.56; 135%), the leukocyte count increased only by 12%. In “AU” groups the increase was smaller, while “R” groups showed slight changes only. LAR can be applicable in animal experiments and may serve as a supplementary parameter in hemorheological investigations of hyposplenic-asplenic states. Show more

Keywords: Splenectomy, spleen autotransplantation, spleen resection, vaccination, leukocyte antisedimentation rate

DOI: 10.3233/CH-2010-1308

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 289-294, 2010

Authors: Helling, H. | Schenk, H.J. | Pindur, G. | Weinrich, M. | Wagner, B. | Stephan, B.

Article Type: Research Article

Abstract: Septic and haemorhagic shock carry the risk of high mortality. Failure of microcirculation secondary to alterations of haemostasis and fibrinolysis play a major role in the pathogenesis of shock. The aim of this study was to evaluate the clinical relevance of procoagulatory and fibrinolytic activities referring to survival. Therefore, 39 patients (23 to 80 yrs, 16 females, 23 males) suffering from haemorrhagic (n = 21) and septic shock (n = 18) were screened prospectively for plasmatic coagulation and fibrinolysis parameters. Thirteen patients (33.3%) developed lethal outcome. Concerning fibrinolysis, plasminogen was significantly lower in non-survivors by day 1 and plasmin–antiplasmin complex …significantly higher by day 4 compared to survivors. Consecutive increase of plasminogen over day 4 and 7 was significantly stronger in survivors. Concerning haemostasis activation, thrombin–antithrombin complex was higher and D-dimers or fibrinogen levels were lower, but not significantly different, in non-survivors compared to survivors. We conclude from these data, that procoagulant activities are increased, but not significantly predictive for the clinical outcome in septic and haemorrhagic shock. By contrast, fibrinolysis, as measured by enhanced capacity and responsiveness, is clearly predictive and plays a significant role for survival, possibly due to its clearing function in microcirculation. Show more

Keywords: Septicemia, haemorrhage, shock, coagulation, fibrinolysis

DOI: 10.3233/CH-2010-1309

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 295-300, 2010

Authors: Ruef, P. | Craciun, E. | Altfelder, F. | Simon, C. | Frommhold, D. | Koch, L. | Pöschl, J.

Article Type: Research Article

Abstract: Sequestration of activated PMN and enrichment in tissues play a key role in tissue damage during septicaemia and after ischemia/reperfusion. Since polymorphonuclear neutrophilic granulocytes (PMN) of term neonates show various functional differences compared to PMN in adults (decreased chemotaxis, decreased intracellular killing, decreased adhesion) we studied the influence of interleukin 8 (IL-8), tumor necrosis factor-α (TNF-α) and N-formyl-methionyl-leucyl-phenylalanine (fMLP) on the reduction of deformability of PMN in neonates and adults. The following phosphodiesterase (PDE)-inhibitors were applied to ameliorate the reduction in deformability when the PMN were stimulated with fMLP or IL-8: Enoximone, Milrinone (PDE-III-inhibitors), Pentoxifylline (PTX) and Piclamilast (PDE-IV-inhibitors). The …micropipette technique and the cell transit analyzer (CTA) were used and compared. Aspiration times into micropipettes with an internal diameter of 5 μm, transit times through 8 μm filter pores and neutrophil elastase concentrations were determined. Despite of the functional differences of PMN in neonates compared to adults the significant decrease of deformability of PMN activated with cytokines compared to passive PMN was not different in both groups. The neutrophil elastase concentrations reflect the activation of the PMN: highest concentrations during activation, decreased concentrations due to PDE-inhibitors, and PMN in a passive state. The neutrophil elastase concentrations were not different from PMN of neonates and adults. These PDE-inhibitors significantly increased the deformability of activated PMN but significant differences between the deformability of PMN in neonates and adults were not found. Despite the functional differences of PMN in neonates PDE-III/IV-inhibitors lead to similar improvement of mechanical properties of activated PMN in neonates and adults. These drugs may ameliorate impaired microcirculation also in neonates during inflammation. Show more

Keywords: Neonates, PMN, CTA, enoximone, milrinone, PTX, piclamilast

DOI: 10.3233/CH-2010-1311

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 301-310, 2010

Authors: Leithäuser, Boris | Jung, Friedrich | Park, Jai-Wun

Article Type: Research Article

Abstract: Atrial fibrillation (AF), as the most common cardiac rhythm disturbance, gains in importance not only for the persons affected, but also for health care and social economy due to thromboembolic events, of which stroke is the most serious, disabling, and life threatening one. Cardiac embolism is due to thrombus formation mainly in the left atrial appendage (LAA). The pathophysiology leading to increased thrombogenicity is complex and requires a remodelling of the LAA structure, decreased LAA blood flow, activation of inflammatory processes, deviations of the hemostatic/fibrinolytic system, and activation/dysfunction of endothelial/endocardial cells. Altogether, a prothrombotic state proposed by Virchow more than …150 years ago. The presence of a LAA thrombus, therefore, is a result of a dynamic process of clot formation and lysis. A comprehensive understanding of this pathophysiology is helpful to optimize the management of patients at high risk of cardioembolic stroke. Especially those with contraindications for oral anticoagulation are in a need of an alternative approach that is not associated with a long-term risk of hemorrhage and other attendant circumstances. The reasonable alternative may be the exclusion of the LAA cavity from circulation by either surgical or percutaneous catheter-based procedures. Show more

Keywords: Atrial fibrillation, thromboembolism, stroke, anticoagulants, risk, prognosis, aged

DOI: 10.3233/CH-2010-1314

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 311-323, 2010

Authors: Perampaladas, Kumar | Parker, John D. | Gori, Tommaso

Article Type: Research Article

Abstract: Clinical studies have demonstrated that rosiglitazone can improve vascular function in patients with diabetes mellitus. It remains unclear whether this effect depends on a direct improvement in endothelial function or whether it is mediated by the drug’s effect on glycemic control. Yet, rosiglitazone has been linked to serious cardiovascular events. A number of studies recently investigated whether rosiglitazone affects endothelial function in healthy volunteers and patients with cardiovascular disease. Controversial observations have been reported; the observation that rosiglitazone might in certain cases impair endothelial function may suggest a mechanistic explanation for the observation of increased cardiovascular events in patients treated …with rosiglitazone who have underlying cardiovascular disease. These studies are summarized and discussed in the present paper. Show more

Keywords: Diabetes, endothelial function, myocardial infarction, organic nitrates

DOI: 10.3233/CH-2010-1315

Citation: Clinical Hemorheology and Microcirculation, vol. 45, no. 2-4, pp. 325-328, 2010