Clinical Hemorheology and Microcirculation - Volume 30, issue 3-4

Authors: Varlet‐Marie, Emanuelle | Maso, Freddy | Lac, Gérard | Brun, Jean‐Frédéric

Article Type: Research Article

Abstract: Contemporary sports imply huge training volumes, with thus an increasing danger of overloading. The timely detection of the state of overloading in the organism as a whole or in skeletal muscles presents a difficult and complicated problem. A standardized questionnaire has been proposed by the French consensus group on overtraining of the Société Française de Médecine du Sport (SFMS) and allows the calculation of a “score” that may help to quantify the early clinical symptoms of the overtraining syndrome in sportsmen submitted to a heavy training program. We previously reported that this overtraining score is correlated with blood viscosity due …to a correlation of this score with plasma viscosity and hematocrit. When subjects with a high score were compared to subjects with a lower score they appeared to have a higher blood viscosity at native (but not corrected) hematocrit, explained by higher values in both plasma viscosity and hematocrit. By contrast, there was no difference in RBC deformability and aggregation. Therefore, the early signs of overtraining in elite sportsmen are associated with a hemorheologic pattern that suggests some degree of reversal of the “autohemodilution” which characterizes fitness. In a further study we reported that the feeling of heavy legs in overtrained athletes is related to impaired hemorheology. Although well matched with controls for age and body composition, subjects with a complaint of heavy legs had higher plasma viscosity and a higher red cell aggregation as measured with laser backscattering. These findings suggest that the feeling of heavy legs in overtrained athletes are related to hemorheologic disturbances. In the light of the recent concept explaining this syndrome by a mild chronic inflammatory reaction, the investigation of hemorheology in overtraining can be a promising area for hemorheologists, providing both markers and likely pathophysiological explanations for some symptoms of this situation. Show more

Keywords: Blood viscosity, plasma viscosity, hemorheology, erythrocyte deformability, erythrocyte aggregability, exercise, overtraining

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 211-218, 2004

Authors: Khodabandehlou, T. | Le Dévéhat, C.

Article Type: Research Article

Abstract: Diabetes mellitus is associated with vascular abnormalities. Hemorheological variables as well as the transcutaneous oxygen pressure (TcPO2 ) were measured in 38 diabetic patients with critical limb ischemia to assess whether these variables could be of value to follow the deterioration in foot disease. Patients with previous history of foot ulcers or frank ulcers on presentation were followed for foot care. After a 12‐month follow‐up, they were divided into 2 subgroups based on the regression of foot disease: 30% of patients improved foot ischemia, i.e., healed or improved ulcer, while the remainder 70% deteriorated, i.e., impaired ulcer or underwent an …amputation. RBC aggregation, plasma viscosity and fibrinogen level obserevd at baseline visit, were significantly higher in the patients who deteriorated. Blood viscosity values at both shear rates high and low were not significantly different between the 2 subgroups. TcPO2 was significantly lower in patients who deteriorated compared with those who improved. With regard to prognostic values, RBC aggregation parameters and fibrinogen level offered the highest positive predictive values (of 89%, 94%, and 88% respectively), comparable to that associated with TcPO2 (94%). Further analyses showed that combining markers of hemorheology with TcPO2 especially when TcPO2 value is in the range of 10–30 mmHg, may improve prognostic value for the management of the diabetic foot disease. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 219-223, 2004

Authors: Leach, J. Kent | Patterson, Eugene | O'Rear, Edgar A.

Article Type: Research Article

Abstract: Our efforts have focused on investigating the potential benefit of encapsulated thrombolytic agents for treatment of clot‐based crises. Liposome encapsulated plasminogen activators (LEPAs) have demonstrated improved thrombolysis in vivo in multiple laboratories. Compared to free agents, LEPAs demonstrate faster reperfusion times, reduced residual clot masses, and more rapid and complete restoration of blood flow. We have encapsulated streptokinase in both liposomes (LESK) and polymer microcapsules (MESK). Both formulations demonstrated reductions in reperfusion times, residual clot mass, and improved return of flow compared to identical dosages of free streptokinase in a thrombosed rabbit carotid, with MESK resulting in comparable or even …greater improvements. In addition, marked reductions in bleeding complications and ventricular infarct size have been observed in a canine model of acute myocardial infarction. The mechanism for MESK has recently been explored in our laboratory using multiple microscopic techniques. MESK appears to resist adsorption to the leading edge of the thrombus, a common limitation for the permeation of free plasminogen activators. By avoiding adsorption and penetrating the thrombus, greater spatial distribution of the agent within the clot can be achieved. This data suggests that encapsulation of streptokinase could provide a therapeutic option for treatment of thrombosed arteries. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 225-228, 2004

Authors: Caimi, G. | Lo Presti, R. | Montana, M. | Carollo, C. | Amodeo, G. | Romano, A. | Canino, B.

Article Type: Research Article

Abstract: Leukocytes, and in particular polymorphonuclear cells (PMN), play a role in the organ injury that characterizes the progression of vascular atherosclerotic disease (VAD) and diabetes mellitus (DM). We enrolled subjects with VAD, subjects with type 2 DM (DM2) and subjects with VAD and DM2. We evaluated the initial relative flow rate (IRFR) of PMN, using the St.George Filtrometer, the PMN membrane fluidity, labelling intact PMN cells with the fluorescent probe 1.4‐(trimethylamino)‐phenyl‐4‐phenylhexatriene (TMA‐DPH), the PMN cytosolic Ca2+ content marking the cells with the fluorescent probe Fura 2‐AM and the PMN integrin profile using the flow cytofluorimetry. All these evaluations were …effected at baseline and after activation with 4‐phorbol‐12‐myristate‐13‐acetate (PMA). At baseline and after activation the IRFR did not distinguish normal subjects from any group of patients. The PMN membrane fluidity at baseline differentiated only normal from DM2 subjects, while after activation no significant variation of this parameter was observed in normal, VAD, DM2 and VAD‐DM2 subjects. The PMN cytosolic Ca2+ content, at baseline, discriminated only normal from VAD subjects with DM2, while after activation a significant increase of this parameter was evident in DM2 subjects and in VAD subjects with DM2. Regarding the PMN integrin pattern we observed, at baseline and after activation, a complex and non‐univocal behaviour. In conclusion, the PMN rheological and metabolic pattern found in these groups of patients showed only small functional alterations while the integrin pattern was significantly different from that of normal subjects and added specific elements which may have potential therapeutical implications. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 229-235, 2004

Authors: Pongrácz, Endre

Article Type: Research Article

Abstract: Aspirin, ticlopidine and clopidogrel are used as a pharmacological means to efficiently decrease the number of reoccurrence of ischemic stroke (100–325 mg/d). This antiplatelet treatment could prevent the secondary stroke by approximately 22%. Laboratory effective platelet inhibition for the clinician, and methods for routine screening evaluation for the laboratory were studied. (1) For the standardisation of platelet aggregation technology blood samples of 150 healthy persons were studied in 5 centres. CARAT TX computerised optical aggregometer was used for measuring with collagen (2 μg/ml), epinephrine (10 μM), arachidonic acid 0.5 mM and ADP 5 μM as inductors. (2) Laboratory tests were …compared in each centres performed in platelet‐rich plasma of ischemic cardiovascular and stroke patients (n=823) taking 100–325 mg aspirin/d. (3) Blood samples of 555 ischemic stroke patients treated with aspirin (100–325 mg/d), 96 patients treated with ticlopidine (500 mg/d), and 67 patients treated with clopidogrel (75 mg/d) were evaluated, respectively. (1) The mean of maximal aggregation (%) − 2SD of untreated controls (n=150) were detected for collagen with 64%, epinephrine 59% and ADP 62%. (2) In 823 aspirin treated patients were found similar inhibition in different centres with same methods for standardisation. The mean inhibition level was in case of collagen 38%, epinephrine 37% and ADP 61%. (3) The distribution of ineffective platelet inhibition was detected in 17% of aspirin group (collagen and epinephrine), 4% of ticlopidine and 18% of clopidogrel group with ADP, respectively. Our findings were in the stroke cohort: effective inhibition levels: 36% in aspirin group, 73% in ticlopidine and 25% treated with clopidogrel. Platelet aggregation tests could help to find the optimal, and “custom taylored” dose of antiaggregating drugs in the secondary prevention of ischemic stroke. Show more

Keywords: Platelet, aggregation, ischemic stroke, aspirin resistance, ticlopidine, clopidogrel, secondary prevention

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 237-242, 2004

Authors: Marton, Zsolt | Halmosi, Robert | Alexy, Tamas | Horvath, Beata | Toth, Ambrus | Feher, Gergely | Koltai, Katalin | Kesmarky, Gabor | Habon, Tamas | Sumegi, Balazs | Hideg, Kalman | Toth, Kalman

Article Type: Research Article

Abstract: Development of new drugs is a sophisticated process that requires several, different methods. In our experiments we have applied two rheological models to study experimental and clinically used drugs. The antioxidant properties of several agents were estimated by erythrocyte filtration technique. The known antioxidant compound vitamin E was used to validate our measurements. An experimental cardioprotective agent, H‐2545 provided significant protection against oxidative changes in red blood cell filterability (p<0.001). Although some of the examined, known cardiovascular drugs also showed significant antioxidant effect, they were less efficient than H‐2545 and the scavenger effect of this novel agent exceeded the …antioxidant properties of vitamin E. Modification of mexiletine with a pyrroline ring improved significantly its antioxidant capacity suggesting this molecular segment to be responsible for the antioxidant effect. In our second model the antiplatelet effect of experimental poly(ADP‐ribose) polymerase (PARP) inhibitors was evaluated. Two widely used antiplatelet agents: acetyl salicylic acid and eptifibatide served as controls in the validation of the measurements. PARP inhibitors reduced ADP‐induced platelet aggregation in a dose‐dependent manner (p<0.05). However, their hindrance on platelet aggregation waned as the concentration of ADP rose. Regarding the platelets' role in the development of ischemic vascular diseases, the antiaggregating property of PARP inhibitors may exert additional beneficial effects on tissue blood supply under conditions of compromised vascular flow. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 243-252, 2004

Authors: Haase, H. | Jünger, M.

Article Type: Research Article

Abstract: A basic tool in microcirculation research is laser Doppler fluxmetry (LDF). The chaotic behaviour of the measured LDF‐time series acquires mathematical tools like, for instance, Wavelets. The notion of contrast is known as useful tool to measure differences between two LDF‐time series [K. Bräuer, Chaos, Attraktoren und Fraktale, Logos, Berlin, 2002]. The one time series arises from the blood flow in healthy skin and the other from a pigmented symmetric contra lateral skin lesion. Our approach is based on taking the contrast from all shorter non‐overlapping time intervals of approximate length 5 or 10 seconds. This gives a sample or …more precisely, a time series of contrast values. Our goal is an expert system to decide between malign and beligne lesions by estimating the probability for a maligne lesion. As a data base we again use the same data set as [H.‐M. Häfner, K. Bräuer, M. Eichner, A. Steins, M. Möhrle, A. Blum and M. Jünger, Wavelet analysis of cutaneous blood flow in melanocytic skin lesions, J. Vasc. Res., submitted]. The statistical tool is logistic regression. We can show that 93% of data are correctly classified. If we check the expert system against the independent data base of the Greifswald dermatology department we get 78% correctly classified cases. Further work must be done to find a well distributed data base for an expert release system. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 253-262, 2004

Authors: Matschke, K. | Mrowietz, C. | Sternitzky, R. | Jung, F. | Park, J.W.

Article Type: Research Article

Abstract: In this study, the extent to which intramuscular pO2 is influenced by a single HELP‐apheresis (Heparin‐induced Extracorporeal LDL Precipitation) was investigated in 10 patients with cardiac allograft vasculopathy (CAV) and severe lipid disorder. For this purpose, a sterile flexible pO2 microcatheter was inserted into the anterior tibial muscle and pO2 monitoring was begun 10 minutes before starting apheresis treatment. The intramuscular pO2 values were recorded continuously until the end of apheresis treatment and a subsequent 30‐minute further observation phase. The patients with CAV and severe lipid disorder presented with 11.6±3.8 mmHg significantly and pathologically reduced …intramuscular pO2 (p<0.001). LDL apheresis resulted in a significant increase in pO2 in the anterior tibial muscle. Thirty minutes after the end of HELP‐apheresis, intramuscular partial oxygen pressure had increased by 162% and showed values at this point, 30.3±9.8 mmHg, similar to those found in healthy subjects. Show more

Keywords: Microcirculation, cardiac allograft vasculopathy, oxygen tension, LDL apheresis

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 263-271, 2004

Authors: Matschke, K. | Mrowietz, C. | Park, J.W. | Jung, F.

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 273-276, 2004

Authors: Vayá, Amparo | Chorro, Paloma | Juliá, Dolores | Falcó, Cristina | Ortega, Luis | Corella, Dolores | Aznar, Justo

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 30, no. 3-4, pp. 277-281, 2004