Clinical Hemorheology and Microcirculation - Volume 61, issue 4

Authors: Kimura, Tatsushi | Hamada, Hironobu | Taito, Shunsuke | Takahashi, Makoto | Sekikawa, Kiyokazu

Article Type: Research Article

Abstract: AIM: The goal was to evaluate the effects of exercise on the clogginess of blood as well as the effect of increased blood cell count and hematocrit levels after exercise. We also investigated the mechanisms underlying the clogginess of blood. METHODS: The time required for blood to pass through microchannels was measured. We focused on assessing the consecutive passage times for serial 20 μL volumes. We used heparinized peripheral blood obtained from subjects after exercise conducted at three intensity levels. Blood samples were also adjusted to achieve specific hematocrit levels or supplemented by addition of adenosine diphosphate …(ADP). RESULTS: The sequential blood passage times of consecutive 20 μL volumes increased with platelet aggregation and adhesion of white blood cells (WBC). We also observed an increase with blood cell counts and hematocrit levels. These changes occurred after high intensity exercise but not after low or medium intensity exercise. Furthermore, the sequential blood passage times of 20 μL volumes increased with platelet aggregation and adhesion of WBC at an ADP concentration at the threshold of aggregation but not at higher levels of hematocrit. CONCLUSIONS: These findings suggested that high intensity exercise might induce the clogginess of blood by enhanced platelet aggregation and adhesion of WBC. Show more

Keywords: Blood fluidity, exercise intensity, clogginess of blood, white blood cells, platelets

DOI: 10.3233/CH-141893

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 559-569, 2015

Authors: Lemonne, Nathalie | Billaud, Marie | Waltz, Xavier | Romana, Marc | Hierso, Régine | Etienne-Julan, Maryse | Connes, Philippe

Article Type: Research Article

Abstract: Patients with hemoglobin C disease (CC) usually do not develop severe complications in comparison with individuals with sickle cell anemia (SS) or with sickle cell hemoglobin C disease (SC). The present study compared the hematological, biochemical, hemorheological and clinical characteristics of CC patients to those of SS, SC and healthy individuals (AA). Blood viscosity was measured at 225 s −1 with a cone plate viscometer. The hematocrit-to-blood viscosity ratio (HVR), i.e. an index of red blood cell (RBC) oxygen transport effectiveness, was calculated. RBC deformability was determined at 30 Pa by ektacytometry, and RBC aggregation properties by syllectometry. CC and …SC had higher blood viscosity and lower HVR than AA. Nevertheless, HVR was higher in CC compared to SS and tended to be higher than in SC. The CC group exhibited very rigid hyperchromic RBC compared to the three other groups. RBC aggregation abnormalities were observed in CC: low RBC aggregation index and high RBC aggregates strength. Despite these hemorheological abnormalities, CC never had hospitalized painful vaso-occlusive crisis or acute chest syndrome. In contrast, all of them had splenomegaly. Of note, 2 out of 7 CC developed retinopathy or otologic disorders. Whether the blood hyperviscosity and decreased RBC deformability are responsible for these complications is unknown. The higher oxygen transport effectiveness (i.e., HVR) of CC compared to SS is probably at the origin of the very low risk of medical complication in this population. Show more

Keywords: HbC disease, blood viscosity, red blood cell deformability, sickle cell disease

DOI: 10.3233/CH-141906

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 571-577, 2015

Authors: Brun, Jean-Frédéric | Varlet-Marie, Emmanuelle | Raynaud de Mauverger, Eric | Fedou, Christine | Pollatz, Marion

Article Type: Research Article

Abstract: We previously reported that low intensity endurance training in sedentary patients suffering from the metabolic syndrome improves blood rheology, mostly due to a decrease in plasma viscosity correlated with an increase in cardiorespiratory fitness. We investigated whether these findings can be extended to type-2 diabetics. 22 diabetics (11 women and 10 men, age: 52.00 ± 2.9 yr, BMI: 32.47 ± 1.17 kg/m2 ) were tested before and after 2 months. Eight of them were trained (2 to 3×45 min/wk) at the power intensity where lipid oxidation reaches a maximum (LIPOX max) and thirteen served as controls. Over this period the …only significant hemorheological effect of training was a decrease in RBC aggregation “M” (−1.25 ± 0.357 p  = 0.01) in the trained group. Subjects who lost weight exhibited a decrease in plasma viscosity (from 1.46 ± 0.013 to 1.38 ± 0.02 p  <  0.01). Changes in waist circumference are associated with changes in hematocrit (r  =−0.952 p  = 0.01); plasma viscosity (r  =−0.91; p  = 0.03); RBC aggregation (“M” r  = 0.940; p  = 0.02). Subjects can also be divided into those who improved their aerobic capacity VO2max and those whose VO2max decreased or remained unchanged. An increase in VO2max is associated with a decrease in whole blood viscosity (r  =−0.79 p  = 0.06) explained by an improvement in RBC rigidity “Tk” (r  =−0.963 p  = 0.002). This study suggests that in Type 2 diabetic patients: (a) viscosity factors might be less responsive to training than in non diabetic individuals; (b) visceral fat loss is the main determinant of changes in hematocrit, plasma viscosity and RBC aggregation; (c) improvements in aerobic capacity improves blood viscosity via an increase in RBC deformability. Show more

Keywords: Diabetes, exercise training, hemorheology, plasma viscosity

DOI: 10.3233/CH-141916

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 579-589, 2015

Authors: Ozturk, Baris | Arihan, Okan | Coskun, Figen | Dikmenoglu-Falkmarken, Neslihan H.

Article Type: Research Article

Abstract: Acute carbon monoxide (CO) poisoning seriously hinders oxygen delivery to tissues. This harmful effect of CO may be aggravated by accompanying changes in the viscosity of blood. We had previously reported increased plasma viscosity in people chronically exposed to CO. This study was planned to test our hypothesis that acute CO poisoning increases blood viscosity. For this purpose four main parameters contributing to blood viscosity – hematocrit, erythrocyte deformability, erythrocyte aggregation and plasma viscosity – were determined in patients with acute CO poisoning and compared with healthy controls. Plasma viscosity and erythrocyte aggregation tendency were lower in the CO group …(p  <  0.05). Erythrocyte deformability was also lower in CO group (p  <  0.05). Our results indicate that acute CO poisoning has diverse effects on hemorheological parameters such as attenuating hematocrit value, plasma viscosity, erythrocyte aggregation tendency and erythrocyte deformability. Show more

Keywords: Hemorheology, plasma viscosity, erythrocyte deformability, erythrocyte aggregation, hematocrit, acute carbon monoxide poisoning

DOI: 10.3233/CH-141919

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 591-597, 2015

Authors: Loibl, Markus | Lang, Siegmund | Brockhoff, Gero | Gueorguiev, Boyko | Hilber, Franz | Worlicek, Michael | Baumann, Florian | Grechenig, Stephan | Zellner, Johannes | Huber, Michaela | Valderrabano, Victor | Angele, Peter | Nerlich, Michael | Prantl, Lukas | Gehmert, Sebastian

Article Type: Research Article

Abstract: Clinical application of platelet-rich plasma (PRP) and stem cells has become more and more important in regenerative medicine during the last decade. However, differences in PRP preparations may contribute to variable PRP compositions with unpredictable effects on a cellular level. In the present study, we modified the centrifugation settings in order to provide a leukocyte-reduced PRP and evaluated the interactions between PRP and adipose-tissue derived mesenchymal stem cells (ASCs). PRP was obtained after modification of three different centrifugation settings and investigated by hemogram analysis, quantification of protein content and growth factor concentration. ASCs were cultured in serum-free α -MEM …supplemented with autologous 10% or 20% leukocyte-reduced PRP. Cell cycle kinetics of ASCs were analyzed using flow cytometric analyses after 48 hours. Thrombocytes in PRP were concentrated, whereas erythrocytes, and white blood cells (WBC) were reduced, independent of centrifugation settings. Disabling the brake further reduced the number of WBCs. A higher percentage of cells in the S-phase in the presence of 20% PRP in comparison to 10% PRP and 20% fetal calf serum (FCS) advocates the proliferation stimulation of ASCs. These findings clearly demonstrate considerable differences between three PRP separation settings and assist in safeguarding the combination of leukocyte-reduced PRP and stem cells for regenerative therapies. Show more

Keywords: Platelet-rich plasma, PRP, adipose-tissue derived mesenchymal stem cells, growth factor, cell cycle, white blood cells

DOI: 10.3233/CH-141920

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 599-614, 2015

Authors: Pietzsch, Jens | Laube, Markus | Bechmann, Nicole | Pietzsch, Franz-Jacob | Kniess, Torsten

Article Type: Research Article

Abstract: It has been suggested that 2,3-diaryl-substituted indole-based cyclooxygenase-2 (COX-2) inhibitors (2,3-diaryl-indole coxibs) do not only appear as potent anti-inflammatory agents but also show the ability to scavenge reactive oxygen species (ROS). This led to the hypothesis that 2,3-diaryl-indole coxibs also may act as potent inhibitors of oxidative modification of low-density lipoprotein (LDL), which is considered a key factor in atherogenesis. The aim of this study was to explore i) the reactivity of a series of new synthesized 2,3-diaryl-indoles with several well characterized LDL oxidation systems and ii) subsequent effects on an inflammatory/atherogenic microenvironment. The results demonstrate that under the present …experimental conditions2,3-diaryl-indoles showed potent ROS scavenging activity and were able to markedly inhibit LDL oxidation. Subsequently, this led to a substantial decrease of modified LDL uptake by scavenger receptors in THP-1 macrophages in vitro and in rats in vivo . Moreover, modified LDL-mediated monocyte/neutrophil adhesion to endothelial cells, macrophage NFκ B activation, as well as macrophage and endothelial cell cytokine release was diminished in vitro . The reduction of modified LDL-induced atherogenic effects by antioxidant 2,3-diaryl-indole coxibs may widen the therapeutic window of COX-2 targeted treatment. Show more

Keywords: Antioxidants, atherogenesis, selective cyclooxygenase-2 (COX-2) inhibitors (coxibs), inflammation, lipid peroxidation, protein oxidation, radical scavenger, reactive oxygen species (ROS)

DOI: 10.3233/CH-141923

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 615-632, 2015

Authors: Jiang, Li | Hu, Jiliang | Feng, Jiantao | Han, Dong | Yang, Chun

Article Type: Research Article

Abstract: In blood vessels, substrate stiffness of the endothelium varies between different body locations and increases during the progression of multiple sclerosis. As a crucial step of the immune response, lymphocyte function associated antigen-1 (LFA-1)/ intercellular adhesion molecule-1 (ICAM-1) interaction occurs in various tissues and plays a pivotal role in atherosclerosis. However, the contribution of the physical property of endothelium substrate, such as the stiffness, to LFA-1/ICAM-1 interaction and immune-related diseases progression remains largely unknown. In this study, we investigated the influence of substrate stiffness on the adhesion force of LFA-1/ICAM-1 bond and ICAM-1 expression on the endothelial cell apical surface …with an improved in vitro model. A silica microsphere-functionalized atomic force microscopy (AFM) tip was linked to LFA-1 via a polyethylene glycol (PEG) chain, and then approached toward human aortic endothelial cells (HAECs) on polyacrylamide gels of different stiffnesses. The results showed that the adhesion force was elevated on stiff substrates, while the expression of ICAM-1 on the HAECs surface was not influenced by substrate stiffness. A low-dose blebbistatin treatment (5μ mol/L) reduced the adhesion force on both substrates while a high dose blebbistatin treatment (50μ mol/L)) eliminated the adhesion between LFA-1 and ICAM-1, indicating that endothelium substrate stiffness directs the LFA-1/ICAM-1 interaction in a myosin II-dependent manner. These results help to describe the relationship between substrate stiffness and myosin II-dependent LFA-1/ICAM-1 interaction, and may increase the understanding of the pathogenesis and treatment of immune-related diseases. Show more

Keywords: LFA-1, ICAM-1, substrate stiffness, blebbistatin, atherosclerosis

DOI: 10.3233/CH-151951

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 633-643, 2015

Authors: Kuehlmann, Britta | Prantl, Lukas | Michael Jung, Ernst

Article Type: Research Article

Abstract: AIM: To investigate whether there are fundamental sonographic and elastographic criteria to precisely assess different surfaces and fillings of idle breast implants and to determine their most distinctive parameters. This was a comparative study of different unused breast implant materials, neighter in animals nor in humans. This knowledge should be transferred in vivo to develop an objective measurement tool. METHODS: Nine idle breast implants-silicone and polyurethane (PU)-were examined in an experimental study by using ultrasound B-mode with tissue harmonic imaging (THI), speckle reduction imaging (SRI, level 0–4), cross-beam (CB, low, medium, high), photopic and the colour …coded ultrasound-strain elastography with a multifrequency probe (9–15 MHz). Using a standardised protocol the implants’ centre as well as the edge were analysed by one experienced examiner. Two independent readers performed analysis and evaluation. For image interpretation a score was created (score 0:inadequate image, score 5:best image quality). RESULTS: The highest score result for the centre was achieved by using ultrasound with B-mode in addition with CB level medium, SRI level 2, THI and photopic (mean:3.22±SD:1.56), but without any statistic significant difference (t -value = 0.71). With elastography the implants’ edge in general was represented without disruptive artefacts (3.89±0.60) with statistic significant difference (t -value = 5.29). Implants filled with inner cohesive silicone gel II° showed best imaging conditions for their centre via ultrasound (5±0) as well as for their edge via elastography (4.50±0.71). CONCLUSION: Ultrasound-strain elastography and high resolution ultrasound represent a valuable measurement tool to evaluate different properties of idle breast implants. These modified ultrasound examinations could be an additional help for clinical investigations and be correlated with Baker’s Classification. Show more

Keywords: Breast implants, elastography, Baker’s Classification

DOI: 10.3233/CH-151963

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 645-656, 2015

Authors: Tetali, Sarada D. | Jankowski, Vera | Luetzow, Karola | Kratz, Karl | Lendlein, Andreas | Jankowski, Joachim

Article Type: Research Article

Abstract: Uremia is a phenomenon caused by retention of uremic toxins in the plasma due to functional impairment of kidneys in the elimination of urinary waste products. Uremia is presently treated by dialysis techniques like hemofiltration, dialysis or hemodiafiltration. However, these techniques in use are more favorable towards removing hydrophilic than hydrophobic uremic toxins. Hydrophobic uremic toxins, such as hydroxy hipuric acid (OH-HPA), phenylacetic acid (PAA), indoxyl sulfate (IDS) and p-cresylsulfate (pCRS), contribute substantially to the progression of chronic kidney disease (CKD) and cardiovascular disease. Therefore, objective of the present study is to test adsorption capacity of highly porous microparticles prepared …from poly(ether imide) (PEI) as an alternative technique for the removal of uremic toxins. Two types of nanoporous, spherically shaped microparticles were prepared from PEI by a spraying/coagulation process. PEI particles were packed into a preparative HPLC column to which a mixture of the four types of uremic toxins was injected and eluted with ethanol. Eluted toxins were quantified by analytical HPLC. PEI particles were able to adsorb all four toxins, with the highest affinity for PAA and pCR. IDS and OH-HPA showed a partially non-reversible binding. In summary, PEI particles are interesting candidates to be explored for future application in CKD. Show more

Keywords: Adsorption of uremic toxins, chronic kidney disease (CKD), hydrophobic uremic toxins, poly(ether imide), microparticles, uremia

DOI: 10.3233/CH-152026

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 657-665, 2015

Authors: Kumar, Reddi K. | Basu, Sayantani | Lemke, Horst-Dieter | Jankowski, Joachim | Kratz, Karl | Lendlein, Andreas | Tetali, Sarada D.

Article Type: Research Article

Abstract: Current haemodialysis techniques are not capable to remove efficiently low molecular weight hydrophobic uremic toxins from the blood of patients suffering from chronic renal failure. With respect to the hydrophobic characteristics and the high level of protein binding of these uremic toxins, hydrophobic adsorber materials might be an alternative to remove these substances from the plasma of the chronic kidney disease (CKD) patients. Here nanoporous microparticles prepared from poly(ether imide) (PEI) with an average diameter of 90 ± 30 μm and a porosity around 88 ± 2% prepared by a spraying/coagulation process are considered as candidate adsorber materials. …A prerequisite for the clinical application of such particles is their biocompatibility, which can be examined i.e. indirectly in cell culture experiments with the particles’ extracts. In this work we studied the effects of aqueous extracts of PEI microparticles on the viability of THP-1 cells, a human leukemia monocytic cell line, as well as their macrophage differentiation, reactive oxygen species (ROS) generation and inflammation. A high cell viability of around 99 ± 18% and 99 ± 5% was observed when THP-1 cells were cultured in the presence of aqueous extracts of the PEI microparticles in medium A and medium B respectively. The obtained microscopic data suggested that PEI particle extracts have no significant effect on cell death, oxidative stress or differentiation to macrophages. It was further found that the investigated proinflammatory markers in THP-1 cells were not up-regulated. These results are promising with regard to the biocompatibility of PEI microparticles and in a next step the hemocompatibility of the microparticles will be examined. Show more

Keywords: Chronic kidney disease (CKD), cytotoxicity, human monocytic (THP-1) cells, poly(ether imide) microparticles, reactive oxygen species (ROS)

DOI: 10.3233/CH-152027

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 667-680, 2015

Authors: Braune, S. | Fröhlich, G.M. | Lendlein, A. | Jung, F.

Article Type: Research Article

Abstract: BACKGROUND: Thrombogenicity is one of the main parameters tested in vitro to evaluate the hemocompatibility of artificial surfaces. While the influence of the temperature on platelet aggregation has been addressed by several studies, the temperature influence on the adherence of platelets to body foreign surfaces as an important aspect of biomedical device handling has not yet been explored. Therefore, we analyzed the influence of two typically applied incubation-temperatures (22°C and 37°C) on the adhesion of platelets to biomaterials. MATERIAL AND METHODS: Thrombogenicity of three different polymers - medical grade poly(dimethyl siloxane) (PDMS), polytetrafluoroethylene (PTFE) and polyethylene …terephthalate (PET) - were studied in an in vitro static test. Platelet adhesion was studied with stringently characterized blood from apparently healthy subjects. Collection of whole blood and preparation of platelet rich plasma (PRP) was carried out at room temperature (22°C). PRP was incubated with the polymers either at 22°C or 37°C. Surface adherent platelets were fixed, fluorescently labelled and assessed by an image-based approach. RESULTS AND DISCUSSION: Differences in the density of adherent platelets after incubation at 22°C and 37°C occurred on PDMS and PET. Similar levels of adherent platelets were observed on the very thrombogenic PTFE. The covered surface areas per single platelet were analyzed to measure the state of platelet activation and revealed no differences between the two incubation temperatures for any of the analyzed polymers. Irrespective of the observed differences between the low and medium thrombogenic PDMS and PET and the higher variability at 22°C, the thrombogenicity of the three investigated polymers was evaluated being comparable at both incubation temperatures. Show more

Keywords: Biomaterial, thrombogenicity, platelet adhesion, platelet activation, temperature

DOI: 10.3233/CH-152028

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 681-688, 2015

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 61, no. 4, pp. 689-698, 2015