Clinical Hemorheology and Microcirculation - Volume 64, issue 4

Authors: Paprottka, Karolin J. | Waggershauser, Tobias | Rübenthaler, Johannes | Paprottka, Felix J. | Clevert, Dirk A. | Reiser, Maximilian F. | Paprottka, Philipp M.

Article Type: Research Article

Abstract: OBJECTIVE: To evaluate various embolization particles on their physical properties with special regard on morphological variability and elasticity. METHODS: 8 embolization particles (EmboCept® , Contour SE® Microspheres, Embosphere® Micorspheres 400 μm, 500 μm, 1300 μm, Embozene® Microspheres, DC Beads® , Embozene Tandem® ) were evaluated and graduated from 1–6 microscopically due to morphologic changes in vitro before, during and after their catheter passage by 4 blinded reviewers. To facilitate comparison, microscopic images were provided with a scale. RESULTS: All tested particles showed a homogenous shape and morphology before passage through the …simulation catheter. During the passage all particles were elastically deformable, where necessary. After the catheter passage no loss of basic shape was seen. Changes in size were found in 5/8 particles. Grading of morphologic changes varied between mean value of 1.0 and 3.0. No complete destruction or loss of function was seen. CONCLUSION: All tested embolization particles are, regarding their morphological properties in sense of homogenous shape and deformation after catheter passage, a safe treatment option. Tested in vitro no less of functionality regarding physical properties should be expected. Show more

Keywords: Embolization particles, physical properties, morphology, elasticity, catheter passage

DOI: 10.3233/CH-168002

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 887-898, 2016

Authors: Roch, Toralf | Kratz, Karl | Ma, Nan | Lendlein, Andreas

Article Type: Research Article

Abstract: Although frequently used as implants materials, both polydimethylsiloxane (PDMS) and polytetrafluoroethylene (PTFE) are often associated with adverse effects including foreign body responses. Dendritic cells (DC) are crucial for the initiation of immune reactions and could also play a role in foreign body associated inflammations. Therefore, the interaction of DC with PDMS and PTFE was investigated regarding their capacity to induce undesired cell activation. Medical grade PDMS and PTFE films were embedded into polystyrene PS inserts via injection molding to prevent the DC from migrating below the substrate and thereby, interacting not only with the test sample but also with the …culture vessel material. The viability, the expression of co-stimulatory molecules, and the cytokine/chemokine profiles were determined after 24 hours incubation of the DC with PDMS or PTFE. Blank PS inserts and tissue culture polystyrene (TCP) served as reference materials. The viability of DC was not substantially influenced after incubation with PDMS and PTFE. However, both polymers induced DC activation indicated by the upregulation of co-stimulatory molecules. The release profiles of 14 soluble inflammatory mediators showed substantial differences between PDMS, PTFE, PS, and TCP. This study showed the potential of PTFE and PDMS to activate primary human dendritic cells, which could be an explanation for the often observed inflammatory events associated with the implantation of these polymers. Show more

Keywords: Biomaterials, dendritic cells, polydimethylsiloxane, polytetrafluoroethylene, cell culture devices

DOI: 10.3233/CH-168033

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 899-910, 2016

Authors: Ahmadizad, Sajad | Nouri-Habashi, Akbar | Rahmani, Hiwa | Maleki, Majid | Naderi, Nasim | Lotfian, Sara | Salimian, Morteza

Article Type: Research Article

Abstract: BACKGROUND: The effects of high intensity interval training (HIIT) on inflammatory markers and endothelial function have been extensively shown. However, the acute effect of HIIT on platelet activation and function in patients with recent revascularization is unclear. OBJECTIVE: The purpose of present study was to compare the responses of platelet activation (CD62P) and function (platelet aggregation) to high intensity interval exercise (HIIE) and moderate continuous exercise (MCE) in coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI) patients. METHODS: Thirty patients who had CABG or PCI were randomly divided into HIIE, MCE and control …groups. After determining the VO2peak , subjects in the MCE group carried out 30 min of continuous exercise at 60% of VO2peak , whereas, the subjects in HIIE group performed an interval protocol consisted of 8 repetitions of 2 min activity (running on treadmill) at 90% of VO2peak interspersed by 2 min of active recovery between repetitions at 30% of VO2peak .  Subjects in control group were seated and had no activity for the same period of time. Two blood samples were collected before and immediately after exercise and were analyzed for markers of platelet activation and function. RESULTS: Data analyzes revealed that increases in platelet aggregation induced by ADP and corrected for increases in platelet count in response to MCE trial was significantly lower than HIIE group (P  < 0.05). In addition, responses of CD62P to MCE trial was significantly lower compared to HIIE group (P  < 0.05). Changes in plateletcrit and platelet distribution width were significantly different among the three trials where the PCT and PDW following the HIIE were higher than MCE. Platelet count increased significantly (P  < 0.05) by 13% following HIIE trial. CONCLUSIONS: Based on the findings of the present study it could be concluded that the risk of exercise-induced thrombosis is higher during HIIE than MCE in patients with recent revascularization. Show more

Keywords: Interval exercise, acute exercise, platelet aggregation, p-selectin, CD62P

DOI: 10.3233/CH-168010

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 911-919, 2016

Authors: Basarab, M.A. | Basarab, D.A. | Konnova, N.S. | Matsievskiy, D.D. | Matveev, V.A.

Article Type: Research Article

Abstract: OBJECTIVE: The aim of this work was to develop a novel technique for digital processing of Doppler ultrasound blood flow sensor data from noisy blood flow velocity waveforms. METHODS: To evaluate the fluctuating blood flow parameters, various nonlinear dynamics methods and algorithms are often being used. Here, for identification of chaotic and noise components in a fluctuating coronary blood flow, for the first time the Allan variance technique was used. Analysis of different types of noises (White, Brownian, Flicker) was carried out and their strong correlation with fractality of time series (the Hurst exponent) was revealed. …RESULTS: Based on a specialized software realizing the developed technique, numerical experiments with real clinical data were carried out. Recommendations for identification of noisy patterns of coronary blood flow in normal and pathological states were developed. CONCLUSION: The methodology gives us the possibility for the more detailed quantitative and qualitative analysis of a noisy fluctuating blood flow data. Show more

Keywords: Blood flow, Doppler flowmetry, Allan variance, Hurst exponent, nonlinear dynamics, Alavar

DOI: 10.3233/CH-168011

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 921-930, 2016

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

Article Type: Research Article

Abstract: Accumulated uremic toxins like indoxyl sulphate, hippuric acid and p-cresyl sulphates in renal failure patients stimulate proinflammatory effects, and consequently kidney and cardiovascular diseases. Low clearance rate of these uremic toxins from the blood of uremic patients by conventional techniques like hemodialysis is due to their strong covalent albumin binding (greater than 95%) and hydrophobic nature, which led to alternatives like usage of hydrophobic adsorber’s in removing these toxins from the plasma of kidney patients. Polymers like polyethylene, polyurethane, polymethylmethacrylate, cellophane and polytetrafluoroethylene were already in use as substitutes for metal devices as dialysis membranes. Among new synthetic polymers, one …such ideal adsorber material are highly porous microparticles of poly(ether imide) (PEI) with diameters in the range from 50–180μ m and a porosity around 88±2% prepared by a spraying and coagulation process. It is essential to make sure that these synthetic polymers should not evoke any inflammatory or apoptotic response during dialysis. Therefore in our study we evaluated in vitro effect of PEI microparticle extracts in human aortic endothelial cells (HEACs) concerning toxicity, inflammation and apoptosis. No cell toxicity was observed when HAECs were treated with PEI extracts and inflammatory/apoptotic markers were not upregulated in presence of PEI extracts. Our results ensure biocompatibility of PEI particles and further hemocompatibility of particles will be tested. Show more

Keywords: Poly(ether imide) (PEI), biomaterial, inflammation, apoptosis, medical devices, Tumor necrosis factor-alpha(TNF-α)

DOI: 10.3233/CH-168046

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 931-940, 2016

Authors: Tzoneva, Rumiana | Uzunova, Veselina | Apostolova, Sonia | Krüger-Genge, Anne | Neffe, Axel. T. | Jung, Friedrich | Lendlein, Andreas

Article Type: Research Article

Abstract: Angiogenesis is one of the key processes during development, wound healing and tumor formation. Prerequisite for its existence is the presence of endogenous electrical fields (EFs) generated by active ion transport across polarized epithelia and endothelia, and appearance of the transcellular potentials. During angiogenesis cellular factor as endothelial growth factor (VEGF), synthesis of adhesive proteins and membrane metalloproteinases (MMPs) govern the angiogenic response to different external stimuli as biomaterials interactions and/or exogenous EF. Gelatin-based hydrogels with elasticities comparable to human tissues have shown to influence cell behavior as well as cell attachment, protein synthesis, VEGF and MMP’s production after the …application of EF. Gelatin-based matrices with 3 (G10_LNCO3), 5 (G10_LNCO5), and 8 (G10_LNCO8) fold excess of isocyanate groups per mol of amine groups present in gelatin were used. Human umbilical endothelial cells (HUVEC) (Lonza Basel, Switzerland) and highly invasive breast cancer MDA-MB-231 cells (ATCC®HTB-26TM ) were used. For an estimation of the amount of VEGF released from cells a commercially available VEGF ELISA (Thermo Fisher Scientific, Germany) kit was used. Fibronectin (FN) enzyme immunoassay (EIA) was used to analyze the secreted amount of FN by cells seeded on the materials. Secreted MMPs were analyzed by zymography. Gelatin-based hydrogels attracted HUVEC adhesion and diminished the adhesion of MDA-MB-231 cells. The applied direct current (DC) EF induced an almost 5–fold increase in VEGF production by HUVEC seeded on gelatin-based hydrogels, while in contrast, the applied EF decreased the production of VEGF by cancer cells. FN synthesis was elevated in HUVEC cells seeded on gelatin-based materials in comparison to FN synthesis by cancer cells. HUVEC seeded on gelatin hydrogels showed an expression mainly of MMP-2. The application of EF increased the production of MMP-2 in HUVEC seeded on gelatin materials. In contrast, for MDA-MB-231 the production of MMPs on gelatin materials was lower compared to control materials. With the application of EF the levels of MMP-9 decreased but MMP-2 expression raised significantly for gelatin materials. Overall, the results showed that studied gelatin materials suppressed attachment of cancerous cells, as well as suppressed their angiogenic potential revealed by decreased VEGF and MMP production. Thus, this study approved gelatin-based hydrogels with proper elasticity characteristics and different degradation behavior as useful matrices for use in vascular tissue regeneration or in restriction of tumor growth after tumor resection. Show more

Keywords: Angiogenesis, gelatin hydrogels, VEGF production, FN synthesis, MMPs expression

DOI: 10.3233/CH-168040

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 941-949, 2016

Authors: Duarte, Catarina | Napoleão, Patrícia | Freitas, Teresa | Saldanha, Carlota

Article Type: Research Article

Abstract: INTRODUCTION: Acetylcholinesterase (AChE) is located on outer surface of erythrocyte membrane. Gender-related differences in erythrocyte AChE enzyme activity had been verified in young adults. It is also known that binding of acetylcholine (ACh) with AChE on erythrocyte membrane initiates a signal transduction mechanism that stimulates nitric oxide (NO) efflux. AIMS: This ex vivo study was done to compare the amount of NO efflux obtained from erythrocytes of healthy donors in males and females. METHODS: We included 66 gender age-matched healthy donors (40–60 years old). We performed quantification of erythrocyte NO efflux from erythrocytes and …of the membrane AChE enzyme activity. RESULTS: There are no significant differences in NO efflux from erythrocytes between men and women. Regarding AChE enzyme activity values, in this range of age, no differences between genders were obtained. However, the values of AChE enzyme activity in the third quartile of NO efflux values were significantly higher (p  < 0.05) in women than in men. CONCLUSIONS: The efflux of NO from erythrocyte of healthy humans did not change with gender. For the same range of values of NO efflux from erythrocytes, in both gender, it was verified higher values of AChE enzyme activity in women. Show more

Keywords: Gender, erythrocyte, nitric oxide, acetylcholinesterase

DOI: 10.3233/CH-168023

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 951-955, 2016

Authors: Aguiar, Laura | Matos, Andreia | Gil, Ângela | Afonso, Conceição | Almeida, Salomé | Braga, Lígia | Lavinha, João | Kjollerstrom, Paula | Faustino, Paula | Bicho, Manuel | Inácio, Ângela

Article Type: Research Article

Abstract: BACKGROUND: Sickle cell anemia (SCA) is an inherited blood disorder. SCA patients present clinical and hematologic variability that cannot be only explained by the single mutation in the beta-globin gene. Others genetic modifiers and environmental effects are important for the clinical phenotype. SCA patients present arginine deficiency that contributes to a lower nitric oxide (NO) bioactivity. OBJECTIVE: The aim of this work is to determine the association between hematological and biochemical parameters and genetic variants from eNOS gene, in pediatric SCA patients. METHODS: 26 pediatric SCA patients were genotyped using polymerase chain reaction (PCR) …and restriction fragment length polymorphism (RFLP) techniques in three important eNOS gene polymorphisms - rs2070744, rs1799983 and intron 4 VNTR. RESULTS: Results from this study show a significant statistical association between some parameters and genetic variants: an increased reticulocyte count and high serum lactate dehydrogenase levels were associated with both the rs2070744_TT and the rs1799983_GG genotypes at eNOS gene and high levels of neutrophils were associated with the eNOS4a allele at intron 4 VNTR. CONCLUSIONS: Our results reinforce the importance of NO bioactivity in SCA. We presume that NO, and its precursors might be used as therapy to improve the quality of life of SCA patients. Show more

Keywords: Sickle cell anemia, genetic modifiers, nitric oxide

DOI: 10.3233/CH-168008

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 957-963, 2016

Authors: Napoleão, Patrícia | Potapova, Ekaterina | Moleirinho, Sara | Saldanha, Carlota | Messias, António

Article Type: Research Article

Abstract: AIM: Soluble CD40 ligand (sCD40L) has been considered as a marker of thrombosis and inflammation in several diseases, including sepsis. Recent studies challenge this view and point to a role of sCD40L in vascular and endothelial function. An indication of that association in sepsis has not been obtained so far. Therefore, herein we evaluated association between sCD40L and markers of hemorheology and inflammation on context of septic shock. METHODS: Time-changes of sCD40L levels over 72 hours of Intensive Care Unit (ICU) internment were assessed in 22 patients with septic shock and compared with 36 healthy volunteers. Association of sCD40L …levels with erythrocyte deformability and aggregation (as markers of hemorheology), plasma concentrations of haemoglobin (Hb, as markers of endothelial function) and white blood cells (WBC) count (as marker of low-grade inflammation) were assessed in patients with septic shock. RESULTS: At ICU admission, sCD40L concentrations in patients with septic shock were lower (p  = 0.024) than levels of healthy volunteers. However, sCD40L did not change over 72 hours of internment (F = 2.1, p  = 0.137). Soluble CD40L levels in patients with septic shock at ICU admission correlate with concentrations of Hb (r  = 0.61, p  = 0.00) and WBC count (r  = 0.63, p  = 0.00), but not to erythrocyte deformability (r ≥0.157, p ≤0.235) and aggregation (r ≥–0.109, p ≤0.192). CONCLUSIONS: These results seem to highlight a possible association of sCD40L to endothelial function and inflammation in septic shock context. Show more

Keywords: Sepsis, sCD40L, haemoglobin, inflammation, hemorheology

DOI: 10.3233/CH-168026

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 965-970, 2016

Authors: Napoleão, Patrícia | Freitas, Teresa | Saldanha, Carlota

Article Type: Research Article

Abstract: AIMS: Oxidized low density lipoprotein (ox-LDL) has been reported as an inhibitor of nitric oxide (NO)-mediated dilatation in microcirculation. Oxidized LDL effect on NO metabolism of erythrocytes is not known. Therefore, this study aims to evaluate the effect of ox-LDL on erythrocytes NO metabolism. METHODS: The effect of different concentrations of human purified ox-LDL (25, 50 and 100 μg/mL) on NO metabolism was evaluated on blood of healthy subjects. RESULTS: An inhibitory effect of higher concentrations of ox-LDL on erythrocyte NO efflux levels was verified. Concentrations of NO efflux from erythrocytes were lower as consequence …of treatments with 50 μg/mL ox-LDL treatment (1.6±0.27 nM) and 100 μg/mL ox-LDL treatment (1.3±0.22 nM) than control (1.9±0.28 nM). Opposite, ox-LDL incubation has a positive effect on GSNO content of erythrocytes. That effect is proportional to concentrations of ox-LDL treatments (10.8±1.4 nM for 25 μg/mL, 12.9±1.5 nM for 50 μg/mL and 12.1±1.9 nM for 100 μg/mL) and is significant relative to control (8.56±0.76 μM) and ACh (8.9±0.52 μM) aliquots. CONCLUSIONS: Presence of oxidized LDL in erythrocyte NO metabolism induces a decrease of NO efflux amount and an increase on intra-erythrocyte GSNO concentrations. These results suggest a role of ox-LDL in mobilization of NO between NO derivatives molecules in dependence of oxidized LDL concentration. An anti - reactive nitrogene role can be attributed to ox-LDL for its contribution in the erythrocyte scavenged ability for nitric oxide. Show more

Keywords: Oxidized LDL, erythrocyte, nitric oxide, S-nitrosoglutathione

DOI: 10.3233/CH-168025

Citation: Clinical Hemorheology and Microcirculation, vol. 64, no. 4, pp. 971-975, 2016