TY - GEN A1 - Mrowietz, Christof A1 - Sievers, H. A1 - Pindur, Gerhard A1 - Hiebl, Bernhard A1 - Jung, Friedrich T1 - Cutaneous microcirculation in patients with peripheral arterial occlusive disease: Comparison of capillary blood circulation in the nail fold of finger and toe T2 - Clinical Hemorheology and Microcirculation N2 - In patients with peripheral arterial occlusive disease (PAOD) a restricted circulation in cutaneous microvessels has been reported. In this study the velocity of erythrocytes (very) in finger nailfold capillaries - a vascular area without upstream macroangiopathy - and also in toe nailfold capillaries - a post-stenotic area –was investigated using capillary microscopy in apparently healthy subjects and patients with PAOD. Already in finger nailfold capillaries very of patients with PAOD under resting conditions was significantly lower than in capillaries of healthy subjects. This was also true for the circulation in toe capillaries. In addition, the erythrocyte velocities under resting conditions in the toe capillaries were significantly lower than in the finger capillaries. Similar results were found for the duration and the maximum velocity of postocclusive hyperemia. It is concluded that the resting blood flow in the skin microcirculation is impaired in PAOD patients, both under resting conditions and during postocclusive hyperemia in finger as well in toe nailfold capillaries. KW - Microcirculation KW - peripheral arterial occlusive disease KW - capillary microscopy Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch209220 U6 - https://doi.org/10.3233/CH-209220 SN - 1875-8622 SN - 1386-0291 VL - 76 IS - 2 SP - 279 EP - 285 ER - TY - GEN A1 - Greif, G. A1 - Mrowietz, Christof A1 - Wendt, M. A1 - Jung, Friedrich A1 - Hiebl, Bernhard A1 - Meyer-Sievers, H. T1 - Differences in human and minipig platelet number, volume and activation induced by borosilicate glass beads in a modified chandler loop-system T2 - Clinical Hemorheology and Microcirculation N2 - The pig is the most widely used large animal model in Europe, with cardiovascular research being one of the main areas of application. Adequate refinement of interventional studies in this field, meeting the requirements of Russel and Burchs’ 3 R concept, can only be performed if blood-contacting medical devices are hemocompatible. Because most medical devices for cardiovascular interventional procedures are developed for humans they are tested mostly for compatibility with human blood. The aim of this study was therefore to determine whether there are differences in behavior of porcine and human platelets when they come into contact with glass, which was used as an exemplary thrombogenic material. For this purpose changes of platelet count, platelet volume and platelet expression of the activation markers CD61, CD62P and CD63 were measured using a modified chandler loop-system simulating the fluidic effects of the blood flow. Minipig and human platelets showed significant differences in number and volume, but not in activation after 4–8 min exposure to glass. KW - Pig KW - minipig KW - platelet activation KW - platelet count KW - platelet volume KW - FACS KW - monoclonal antibody KW - CD42 KW - CD61 KW - CD62P KW - CD63 Y1 - 2021 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch219201 U6 - https://doi.org/10.3233/CH-219201 SN - 1875-8622 SN - 1386-0291 VL - 79 IS - 1 SP - 149 EP - 155 ER - TY - GEN A1 - Park, J. W. A1 - Matschke, K. A1 - Mrowietz, Christof A1 - Krüger-Genge, Anne A1 - Jung, Friedrich T1 - HELP-(Heparin-induced Extracorporeal LDL Precipitation)-apheresis in heart recipients with cardiac allograft vasculopathy and concomitant hypercholesterolemia: Influence of long-term treatment on the microcirculation T2 - Clinical Hemorheology and Microcirculation Y1 - 2019 U6 - https://doi.org/10.3233/CH-199216 SN - 1875-8622 VL - 73 IS - 1 SP - 19 EP - 27 ER - TY - GEN A1 - Nies, A. A1 - Proft, L. A1 - Nehring, M. E. A1 - Gruber, Cnristian A1 - Sievers, H. A1 - Hünigen, Hana A1 - Rodruigues, A. G. A1 - Gemeinhardt, Ole A1 - Mrowietz, Christof A1 - Jung, Friedrich A1 - Hiebl, Bernhard T1 - Growth-related micromorphological characteristics of the porcine femoral artery T2 - Clinical Hemorheology and Microcirculation Y1 - 2019 U6 - https://doi.org/10.3233/CH-199219 SN - 1875-8622 VL - 73 IS - 1 SP - 195 EP - 201 ER - TY - GEN A1 - Greif, G. A1 - Mrowietz, Christof A1 - Meyer-Sievers, H. A1 - Ganter, M. A1 - Jung, Friedrich A1 - Hiebl, Bernhard T1 - Differences in human and sheep platelet adherence, aggregation and activation induced by glass beads in a modified chandler loop-system T2 - Clinical Hemorheology and Microcirculation N2 - In human cardiovascular research, sheep in particular are used as a large animal model in addition to pigs. In these animals, medical products, developed and tested for human medical purposes, are almost exclusively used in interventional studies. Therefore, the extent to which platelets from human and ovine blood differ in terms of adherence, aggregation and activation after a 4- or 8-minutes exposure to glass was investigated. Testing was performed with platelet-rich plasma (PRP) and a modified chandler loop-system, with 4- and 8-minute blood-material exposure times corresponding to 20 and 40 test cycles, respectively, through the entire silicone tube loop of the test system. In sheep and human PRP, contact with the silicone tubing resulted in a decrease in platelet count after 4 minutes and 20 test cycles, respectively. Four more minutes (20 additional test cycles) caused a further decrease of the platelet count only in sheep PRP. When the silicon tube was partly filled with glass beads, these effects were more pronounced and stronger in sheep then in human PRP. The mean platelet volume, which was used as parameter for platelet aggregation, did not change over time in human PRP without glass exposure. With glass exposure in human and sheep PRP the mean platelet volume increased within 40 test cycles, but this increase was stronger in sheep than in human PRP. Regarding activation behavior, the activation markers CD62P and CD63 were detectable only in < 30% (sheep) and < 45% (human) of platelets, whereas after 8 min of glass exposure, the proportion of CD62P+ and CD63+ cells was more increased than before only in sheep. These results indicate that ovine platelets adhere more strongly to glass and show stronger aggregation behavior after glass contact than human platelets, but that ovine and human platelets differ only slightly in activability by glass. KW - Sheep KW - platelet KW - activation KW - platelet volume KW - CD42a KW - CD61 KW - CD62P KW - CD63 Y1 - 2021 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch219104 U6 - https://doi.org/10.3233/CH-219104 SN - 1875-8622 SN - 1386-0291 VL - 79 IS - 1 SP - 129 EP - 136 ER -