@misc{JungKruegerGengeFrankeetal., author = {Jung, Friedrich and Kr{\"u}ger-Genge, Anne and Franke, Ralf-Peter and Hufert, Frank and K{\"u}pper, Jan-Heiner}, title = {COVID-19 and the endothelium}, series = {Clinical Hemorheology and Microcirculation}, volume = {75}, journal = {Clinical Hemorheology and Microcirculation}, number = {1}, issn = {1875-8622}, doi = {10.3233/CH-209007}, pages = {7 -- 11}, abstract = {There is growing evidence that COVID-19 not only affects the lungs but beyond that the endothelial system. Recent studies showed that this can lead to microcirculatory impairments and in consequence to functional disorders of all inner organs. The combination of endothelial dysfunction with a generalized inflammatory state and complement elements may together contribute to the overall pro-coagulative state described in COVID-19 patients leading to venular as well as to arteriolar occlusions.}, language = {en} } @misc{JungLambyPrantletal., author = {Jung, Friedrich and Lamby, Philipp and Prantl, Lukas and Wiggermann, P. and Jung, Ernst Michael and Kr{\"u}ger-Genge, Anne and Franke, Ralf-Peter}, title = {Post-mortem distribution of Iodinated Contrast Media (ICM) (iodixanol versus iopromide) in the porcine kidney after multiple bolus injections in vivo into the supra-renal aorta}, series = {Clinical Hemorheology and Microcirculation}, volume = {85(2023)}, journal = {Clinical Hemorheology and Microcirculation}, number = {3}, issn = {1875-8622}, doi = {10.3233/CH-229102}, pages = {289 -- 295}, language = {en} } @misc{KruegerGengeJungKuepperetal., author = {Kr{\"u}ger-Genge, Anne and Jung, Friedrich and K{\"u}pper, Jan-Heiner and Lehmann, Christian and Franke, Ralf-Peter}, title = {Actin type and distribution in erythrocytes}, series = {Journal of Cellular Biotechnology}, volume = {3}, journal = {Journal of Cellular Biotechnology}, number = {2}, issn = {2352-3697}, doi = {10.3233/JCB-179014}, pages = {81 -- 83}, abstract = {Erythrocytes transport oxygen from the lungs to the tissues. The excess surface area together with the elasticity of the erythrocyte cell membrane provides the flexibility needed to pass through the microvasculature where the oxygen exchange occurs. Although the architecture of the red cell and its membrane-associated cytoskeletal network is known in general, the factors that control the characteristic shape change during echinocyte formation are poorly understood. In this short report we show that in echinocytes a completely reorganized membrane cytoskeleton with a box-like structure of actin filaments prevailed indicating the importance of the actin cytoskeleton during echinocyte formation.}, language = {en} } @misc{LambyMinkowHandtetal., author = {Lamby, Philipp and Minkow, Alexander and Handt, Stefan and Falter, Johannes and Schellenberg, Eva-Lotte and Graf, Stefanie and Hiebl, Bernhard and Haerteis, Silke and Gemeinhardt, Ole and Kr{\"u}ger-Genge, Anne and Klosterhalfen, Bernd and Jung, Ernst Michael and Franke, Ralf-Peter and Momeni, Arash and Prantl, Lukas and Jung, Friedrich}, title = {Histological and SEM assessment of blood stasis in kidney blood vessels after repeated intra-arterial application of radiographic contrast media}, series = {Life}, volume = {10}, journal = {Life}, number = {9}, issn = {2075-1729}, doi = {10.3390/life10090167}, pages = {16}, abstract = {Background: After application of iodinated contrast media (CM), a pronounced deterioration of the microcirculation in skin and myocardium was reported. Clinically, the repeated application of CM, especially, led to an increase of the renal resistance index (RRI). With respect to the transiency of the RRI increase, it is reasonable to assume that the deterioration of blood flow could be due to transient blood stasis caused by reversible morphologic cell alterations due to osmotic discrepancies between CM and human blood. Therefore, the hypothesis was investigated whether CM are able to induce in vivo such blood stasis and cell deformations in the renal vasculature of well-hydrated pigs. Methods: The in vivo study was performed as a prospective randomized examination to compare the effects of two different CM in 16 pigs (German Landrace). Pigs were randomized to receive either Iodixanol (n = 8), or Iopromide (n = 8). Each animal received 10 injections separated by 5-min intervals via the suprarenal aorta at a rate of 10 mL/s according to the usual procedure during a cardiac catheter examination. Finally, the kidneys were explanted and processed for histology (H \& E staining and fibrin staining according to Weigert) as well as for scanning electron microscopy (SEM) with regards to morphologic correlates explaining the changes in the microcirculation. Results: In each of the predefined four categories of vascular diameters, blood stasis were found, but clearly more often after application of Iopromide than after application of Iodixanol (p < 0.001). In addition, Iopromide induced more blood stasis in all of the examined kidney regions compared to Iodixanol (p = 0.0001). There were no obstructive events in the middle cortex following the application of Iodixanol. Except for the region around a puncture channel of a placed-in catheter probe, no fibrin was detected in Weigert's fibrin-stained samples, neither around the histologically assessed thrombi nor in vessels with blood stasis. Complementary SEM analyses revealed in a few cases only a slight generation of fibrin and thrombi and deformations, such as echinocyte and "box-like" deformations. Conclusions: According to previous in vitro studies, pathological erythrocyte deformations, such as echinocyte and box-like formation of erythrocytes, were observed also in vivo. In addition, blood stasis and/or thrombi could be detected in histological samples from explanted kidneys from young pigs after repeated in vivo administration of CM. In only a few cases, mural platelet aggregates within minimal fibrin meshes occurred only after the application of Iopromide.}, language = {en} } @misc{KruegerGengeBlockiFrankeetal., author = {Kr{\"u}ger-Genge, Anne and Blocki, Anna and Franke, Ralf-Peter and Jung, Friedrich}, title = {Vascular Endothelial Cell Biology: An Update}, series = {International Journal of Molecular Sciences}, volume = {20}, journal = {International Journal of Molecular Sciences}, number = {18}, issn = {1422-0067}, doi = {10.3390/ijms20184411}, pages = {22}, language = {en} } @misc{GerkFrankeJungetal., author = {Gerk, U. and Franke, Ralf-Peter and Jung, Ernst Michael and Scheller, B. and Kr{\"u}ger-Genge, Anne and Jung, Friedrich}, title = {Imaging of coronary arteries using ionic versus non-ionic radiographic contrast media: Intraindividual comparison study}, series = {Clinical Hemorheology and Microcirculation}, journal = {Clinical Hemorheology and Microcirculation}, issn = {1875-8622}, doi = {10.3233/CH-199217}, pages = {8}, language = {en} } @misc{LeeGanesanKruegerGengeetal., author = {Lee, Seahyoung and Ganesan, Ramakrishnan and Kr{\"u}ger-Genge, Anne and Kratz, Karl and Franke, Ralf-Peter and Lendlein, Andreas and Jung, Friedrich}, title = {Substrate-enzyme affinity-based surface modification strategy for endothelial cell-specific binding under shear stress}, series = {Clinical Hemorheology and Microcirculation}, volume = {75}, journal = {Clinical Hemorheology and Microcirculation}, number = {1}, issn = {1875-8622}, doi = {10.3233/CH-190736}, pages = {85 -- 98}, abstract = {Establishing an endothelial cell (EC) monolayer on top of the blood contacting surface of grafts is considered to be a promising approach for creating a hemocompatible surface. Here we utilized the high affinity interactions between the EC plasma membrane expressed enzyme called endothelin converting enzyme-1 (ECE-1) and its corresponding substrate big Endothelin-1 (bigET-1) to engineer an EC-specific binding surface. Since enzymatic cleavage of substrates require physical interaction between the enzyme and its corresponding substrate, it was hypothesized that a surface with chemically immobilized synthetic bigET-1 will preferentially attract ECs over other types of cells found in vascular system such as vascular smooth muscle cells (VSMCs). First, the expression of ECE-1 was significantly higher in ECs, and ECs processed synthetic bigET-1 to produce ET-1 in a cell number-dependent manner. Such interaction between ECs and synthetic bigET-1 was also detectible in blood. Next, vinyl-terminated self-assembled monolayers (SAMs) were established, oxidized and activated on a glass substrate as a model to immobilize synthetic bigET-1 via amide bonds. The ECs cultured on the synthetic bigET-1-immobilized surface processed larger amount of synthetic bigET-1 to produce ET-1 compared to VSMCs (102.9±5.13 vs. 9.75±0.74 pg/ml). The number of ECs bound to the synthetic bigET-1-immobilized surface during 1 h of shearing (5dyne/cm2) was approximately 3-fold higher than that of VSMCs (46.25±12.61 vs. 15.25±3.69 cells/100×HPF). EC-specific binding of synthetic bigET-1-immobilized surface over a surface modified with collagen, a common substance for cell adhesion, was also observed. The present study demonstrated that using the substrate-enzyme affinity (SEA) of cell type-specific enzyme and its corresponding substrate can be an effective method to engineer a surface preferentially binds specific type of cells. This novel strategy might open a new route toward rapid endothelialization under dynamic conditions supporting the long-term patency of cardiovascular implants.}, language = {en} }