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Acetylcholine, the physiological agonist at all muscarinic receptors, alone (“direct effect”) or after pre-stimulation with isoprenaline (“indirect effect”), is known to reduce the force of contraction (FOC) in human atrial preparations (HAP). We hypothesized that muscarine might act similar to acetylcholine. During open heart surgery for severe coronary heart disease, HAP were obtained. Using digital polymerase chain reaction...
There are five muscarinic receptor subtypes expressed in the human heart. The main subtype is the M 2 -muscarinic receptor. We hypothesized that overexpression of the M 2 -muscarinic receptor should augment any contractile effects that are M 2 -muscarinic receptor–mediated. Therefore, we generated a transgenic mouse with overexpression of the human M 2 -muscarinic receptor under the control of the heart-specific α-myosin heavy...
Stimulation of histamine H1-receptors produces a positive inotropic effect in the human atriumNARA Subscribed
There is a controversy whether histamine H 1 -receptor activation raises or lowers or does not affect contractility in the human heart. Therefore, we studied stimulation of H 1 -receptors in isolated electrically stimulated (one beat per second) human atrial preparations (HAP). For comparison, we measured force of contraction in left atrial preparations (LA) from mice with overexpression of the histamine H 1 -receptor in the h...
Natural and Human Disturbances Have Non‐Linear Effects on Whole‐Ecosystem Carbon Storage in an African SavannaNARA Subscribed
Uncertainties in carbon storage estimates for disturbance‐prone dryland ecosystems hinder accurate assessments of their contribution to the global carbon budget. This study examines the effects of land‐use change on carbon storage in an African savanna landscape, focusing on two major land‐use change pathways: agricultural intensification and wildlife conservation, both of which alter disturbance regimes. By adapting tree inve...
Initial characterization of a transgenic mouse with overexpression of the human D1-dopamine receptor in the heartNARA Subscribed
Dopamine can exert effects in the mammalian heart via five different dopamine receptors. There is controversy whether dopamine receptors increase contractility in the human heart. Therefore, we have generated mice that overexpress the human D 1 -dopamine receptor in the heart (D 1 -TG) and hypothesized that dopamine increases force of contraction and beating rate compared to wild-type mice (WT). In D 1 -TG hearts, we ascertain...
Meta-review on Perforation Model of Subarachnoid Hemorrhage in Mice: Filament Material as a Possible Moderator of MortalityNARA Subscribed
Robust preclinical models are inevitable for researchers to unravel pathomechanisms of subarachnoidal hemorrhage (SAH). For the mouse perforation model of SAH, the goal of this meta-review was the determination of variances in mortality, SAH severity grade, and vasospasm, and their experimental moderators, as many researchers are facing with incomparable results. We searched on the databases PubMed , Embase , and Web of Scienc...
Subcellular spatio-temporal intravital kinetics of aflatoxin B1 and ochratoxin A in liver and kidneyNARA Subscribed
Local accumulation of xenobiotics in human and animal tissues may cause adverse effects. Large differences in their concentrations may exist between individual cell types, often due to the expression of specific uptake and export carriers. Here we established a two-photon microscopy-based technique for spatio-temporal detection of the distribution of mycotoxins in intact kidneys and livers of anesthetized mice with subcellular...
Diversity patterns and palaeoecology of benthic communities of the Kanosh Formation (Pogonip Group, Utah, western USA)NARA Subscribed
The Dapingian to Darriwilian Kanosh Formation is one of the most fossiliferous units of the Pogonip Group (Great Basin, western US). It records a critical phase of the so-called Great Ordovician Biodiversification Event (GOBE) during which many marine clades diversified on lower systematic levels. However, a comprehensive palaeoecological analysis has not been presented for this unit so far. Based on newly collected material f...
Soil water solutes reduce the critical micelle concentration of quaternary ammonium compoundsNARA Subscribed
Quaternary alkyl ammonium compounds (QAACs) are produced in large quantities for use as surfactants and disinfectants and also found in soils, sediments, and surface waters, where they are potentially involved in the selection of antibiotic resistance genes. Micelle formation influences fate and effects of QAACs. The critical micelle concentration (CMC) of six homologs of benzylalkylammonium chlorides (BAC) was determined in d...
Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyon...
In 2019, the EPMA celebrated its 10th anniversary at the 5th World Congress in Pilsen, Czech Republic. The history of the International Professional Network dedicated to Predictive, Preventive and Personalised Medicine (PPPM / 3PM) is rich in achievements. Facing the coronavirus COVID-19 pandemic it is getting evident globally that the predictive approach, targeted prevention and personalisation of medical services is the opti...