A5017239585- Ion Transport and Channel Regulation
- Hormonal Regulation and Hypertension
- Ion channel regulation and function
- Force Microscopy Techniques and Applications
- Lipid Membrane Structure and Behavior
- Electrolyte and hormonal disorders
- Nuclear Structure and Function
- Renal function and acid-base balance
- Cellular Mechanics and Interactions
- Sodium Intake and Health
- Pancreatic function and diabetes
- RNA Research and Splicing
- Neuroscience and Neuropharmacology Research
- Nitric Oxide and Endothelin Effects
- ATP Synthase and ATPases Research
- Biomedical and Chemical Research
- Neuroscience and Neural Engineering
- Renal and related cancers
- RNA Interference and Gene Delivery
- Cell Adhesion Molecules Research
- Electrochemical Analysis and Applications
- Cardiac electrophysiology and arrhythmias
- Trauma, Hemostasis, Coagulopathy, Resuscitation
- Electrochemical sensors and biosensors
- 3D Printing in Biomedical Research
University of Münster
2011-2021
University Hospital Münster
2004-2017
Czech Academy of Sciences, Institute of Physiology
2002-2015
Centre de Recherche des Cordeliers
2013
Inserm
2013
Sorbonne Université
2013
Université Paris Cité
2013
University of Würzburg
1991-2007
Leiden University
2006
Universidade Tiradentes
2001
Dietary salt plays a major role in the regulation of blood pressure, and mineralocorticoid hormone aldosterone controls homeostasis extracellular volume. Recent observations suggest that small increase plasma sodium concentration may contribute to pressor response dietary salt. Because endothelial cells are (i) sensitive aldosterone, (ii) physical contact with sodium, (iii) crucial regulators vascular tone, we tested whether acute changes concentration, within physiological range, can alter...
We present a procedure that allows reliable determination of the elastic (Young’s) modulus soft samples, including living cells, by atomic force microscopy (AFM). The standardized nanomechanical AFM (SNAP) ensures precise adjustment optical lever system, prerequisite for all kinds spectroscopy methods, to obtain values independent instrument, laboratory and operator. Measurements hydrogel samples with well-defined using different AFMs revealed uncertainties in deflection sensitivity...
The dynamics at the plasma membrane resulting from secretory vesicle docking and fusion compensatory endocytosis has been difficult to observe in living cells primarily due limited resolution light microscopic level. Using atomic force microscope, we have able image record changes structure ultrahigh after stimulation of secretion isolated pancreatic acinar cells. “Pits” measuring 500–2000 nm containing 3–20 depressions 100–180 diameter were observed only apical region time course an...
Many mucosal pathogens use type III secretion systems for the injection of effector proteins into target cells. The III-secreted EspB and EspD enteropathogenic Escherichia coli (EPEC) are inserted cell membrane. Together with EspA, these supposed to constitute a molecular syringe, channelling other host cell. In this model, would represent tip needle forming pore membranes. Although contact-dependent Esp-mediated haemolytic activity by EPEC has already been described, formation putative...
Sodium overload stiffens vascular endothelial cells in vitro and promotes arterial hypertension vivo. The hypothesis was tested that the glycocalyx (eGC), a mesh of anionic biopolymers covering surface endothelium, participates stiffening process. By using mechanical nanosensor, mounted on an atomic force microscope, height (∼400 nm) stiffness (∼0.25 pN/nm) eGC luminal split-open human umbilical arteries were quantified. In presence aldosterone, increase extracellular sodium concentration...
In the presence of aldosterone, plasma sodium in high physiological range stiffens endothelial cells and reduces release nitric oxide. We now demonstrate effects extracellular potassium on stiffness individual cultured bovine aortic by using tip an atomic force microscope as a mechanical nanosensor. An acute increase swells softens cell increases A concentration, prevents these changes. propose that are caused submembranous cortical fluidization because actin depolymerization induced...
The hypothesis was tested if the mineralocorticoid hormone aldosterone stimulates Na+/H+ exchange in "giant cells" fused from individual target cells of distal nephron frog kidney. By means microelectrodes, steady-state intracellular pH (pHi) and pHi recovery an acid load were recorded continuously while exposed to aldosterone. Twenty minutes after addition hormone, started rise reached a new steady state about 60 min (delta = 0.28 +/- 0.01). After treatment, recovered significantly faster...
Endothelial dysfunction contributes to the increased cardiovascular risk that accompanies CKD. We hypothesized soluble VEGF receptor 1 (sFlt-1), a antagonist, plays role in endothelial and decreased angiogenesis enrolled 130 patients with CKD stages 3 5 56 age- gender-matched control patients. Plasma sFlt-1 levels were higher and, after multivariate regression analyses, exclusively associated renal function of vWF, marker dysfunction. Compared serum from patients, both recombinant had...
The endothelial glycocalyx (eGC), a carbohydrate-rich layer lining the luminal side of endothelium, regulates vascular adhesiveness and permeability. Although central to pathophysiology barrier dysfunction in sepsis, damage has been generally understudied, part because aberrancy vitro preparations its degradation during tissue handling. aim this study was analyze inflammation-induced eGC on living cells by atomic-force microscopy (AFM) nanoindentation technique. AFM revealed existence mature...
The endothelial glycocalyx (eGC), a carbohydrate-rich layer lining the luminal surface of endothelium, provides first vasoprotective barrier against vascular leakage and adhesion in sepsis vessel inflammation. Angiopoietin-2 (Angpt-2), an antagonist endothelium-stabilizing receptor Tie2 secreted by cells, promotes permeability through cellular contraction junctional disintegration. We hypothesized that Angpt-2 might also mediate breakdown eGC. Using confocal atomic force microscopy, we show...
There is increasing evidence for an additional acute, nongenomic action of the mineralocorticoid hormone aldosterone on renal epithelial cells, leading to a two-step model electrolyte excretion. We investigated acute effect intracellular free Ca2+ and pH in aldosterone-sensitive Madin-Darby canine kidney cell clone. Within seconds application aldosterone, but not glucocorticoid hydrocortisone, there was 3-fold sustained increase at half-maximal concentration 10(-10) mol/liter. Omission...
Abstract Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that cleave and degrade a wide spectrum of extracellular matrix components. By enhancing turnover matrix, MMP activity is also known to play key role in tumor cell invasion. Because protease requires efficient release these proteases the cellular surface, we investigated storage, transport, exocytosis MMP-2 MMP-9 human melanoma cells using immunofluorescence, electrical, biochemical techniques. Immunolabeling with...
Aldosterone has long been known to control water and electrolyte balance by acting on mineralocorticoid receptors in kidney. However, recent studies demonstrated the presence of these nonclassical locations, including cardiovascular system. We tested hypothesis whether endothelial cells respond aldosterone with changes cell volume, a measure for ion-mediated movement across membrane. By means atomic force microscopy fluid, we measured volume adherent human umbilical venous exposed 72 hours...
Liddle syndrome, an inherited form of hypertension, is caused by gain-of-function mutations in the epithelial Na(+) channel (ENaC), principal mediator reabsorption kidney. Accordingly, disease pathology was ascribed to a primary renal mechanism. Whether this sole responsible mechanism, however, remains uncertain as dysregulation ENaC other tissues may also be involved. Previous work indicates that vascular endothelium crucial for regulation cellular mechanics and thus function. The hormone...