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Thomas Kubin Praveen Gajawada Peter Bramlage Stefan Hein Benedikt Berge Ayse Cetinkaya Heiko Burger Markus Schnburg Wolfgang Schaper Yeong-Hoon Choi Manfred Richter 《International journal of molecular sciences》2022,23(3)
Oncostatin M (OSM), a member of the interleukin-6 family, functions as a major mediator of cardiomyocyte remodeling under pathological conditions. Its involvement in a variety of human cardiac diseases such as aortic stenosis, myocardial infarction, myocarditis, cardiac sarcoidosis, and various cardiomyopathies make the OSM receptor (OSMR) signaling cascades a promising therapeutic target. However, the development of pharmacological treatment strategies is highly challenging for many reasons. In mouse models of heart disease, OSM elicits opposing effects via activation of the type II receptor complex (OSMR/gp130). Short-term activation of OSMR/gp130 protects the heart after acute injury, whereas chronic activation promotes the development of heart failure. Furthermore, OSM has the ability to integrate signals from unrelated receptors that enhance fetal remodeling (dedifferentiation) of adult cardiomyocytes. Because OSM strongly stimulates the production and secretion of extracellular proteins, it is likely to exert systemic effects, which in turn, could influence cardiac remodeling. Compared with the mouse, the complexity of OSM signaling is even greater in humans because this cytokine also activates the type I leukemia inhibitory factor receptor complex (LIFR/gp130). In this article, we provide an overview of OSM-induced cardiomyocyte remodeling and discuss the consequences of OSMR/gp130 and LIFR/gp130 activation under acute and chronic conditions. 相似文献
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Prof. Dr. Manfred Grote Dipl. Chem.-Ing. Didem Hanim Meriç Dr. Georg Langenkämper Dr. Heiko Hayen Dr. Thomas Betsche Prof. Dr. Mechthild Freitag 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2009,4(3-4):287-304
Investigation on the transfer of pharmacologically active substances used in animal husbandry into leek and cabbage. The potential of leek and cabbage for uptake of highly prescribed veterinary drugs (antibiotics) was tested in hydroponically grown plants. For this purpose the antibiotics sulfadiazine (SFD), enrofloxacine (ENR), tetracycline (TC), chlortetracycline (CTC) and monensine (MON) were chosen. A further aim was to gain data on the situation of vegetables grown in agricultural practise with regard to antibiotic residues. The evident effects of the antibiotics on plants grown hydroponically (each antibiotic was administered at 5 μmol/l nutrient solution) were greatly different: With regard to leek there were no visible effects (MON, SFD), a weak bleaching of the younger leaf sections (CTC), and strong effects of ENR. The (phytotoxic) effects of antibiotics on cabbage were much more distinct. CTC caused a yellowing of the plant vasculature in cabbage. MON induced lesions on some leaves and finally led to leaf wilting. With administration of ENR a nearly complete bleaching of young leaves was observed. Using LC-MS/MS-methods (low-resolution and high-resolution MS) the administered antibiotics, as well as conversion products and metabolites, were separately identified and quantified in various organs of leek (roots, young and old sections of leaves) and cabbage (roots, stalks, young and old leaves). Depending on the type of antibiotic, vegetable species, and plant organ, the detected concentrations of antibiotic residues comprised several orders of magnitude ranging from μg/kg to mg/kg of fresh weight (fw). The highest concentrations of antibiotics were found in roots of both vegetable species: CTC and TC were detected at approximately 10 mg/kg fw in cabbage roots and at approximately 20 mg/kg fw in leek roots and ENR was determined at approximately 12 mg/kg fw in cabbage roots. Low amounts of ENR were metabolised to ciprofloxacine (CIP). ENR occurred at similar concentrations of approximately 7 mg/kg fw in roots and old leaves of cabbage, indicating a high transport rate of this antibiotic in the cabbage plant. In stalks, young and old leaves of cabbage and in young and old leaf sections of leek all administered antibiotics were detected. Within these antibiotics, ENR and CTC and their conversion products, e. g. demeclocycline (DMC) and TC, occurred at the highest concentrations. SFD and MON were found in considerably lower concentrations (<100 μg/kg fw). The results of our experiments in hydroponic cultures, using defined concentrations of antibiotics in the nutrient solution, evidently demonstrate that cabbage and leek have a very high potential for uptake of a number of veterinary antibiotic drugs, especially for tetracycline and ENR. 相似文献
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Ein Ma?nahmenpaket, bestehend aus dem Spielraumgesetz, dem Beschluss von entsprechenden F?rderungsrichtlinien sowie Novellierungen
des Baugesetzes und der Kinderspielplatzverordnung und einer überarbeitung der Wohnbaufondsrichtlinie, soll dazu beitragen,
dass sich das Bundesland Vorarlberg als besonders kinder- und jugendfreundliche Region etabliert. Hiefür gilt es, ?ffentliche
und private Spielpl?tze und Freir?ume bedarfsgerecht zu erhalten, zu sanieren, neu zu errichten und untereinander zu vernetzen. 相似文献
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The neural mechanisms underlying motion segregation and integration still remain unclear to a large extent. Local motion estimates
often are ambiguous in the lack of form features, such as corners or junctions. Furthermore, even in the presence of such
features, local motion estimates may be wrong if they were generated near occlusions or from transparent objects. Here, a
neural model of visual motion processing is presented that involves early stages of the cortical dorsal and ventral pathways.
We investigate the computational mechanisms of V1-MT feedforward and feedback processing in the perception of coherent shape
motion. In particular, we demonstrate how modulatory MT-V1 feedback helps to stabilize localized feature signals at, e.g.
corners, and to disambiguate initial flow estimates that signal ambiguous movement due to the aperture problem for single
shapes. In cluttered environments with multiple moving objects partial occlusions may occur which, in turn, generate erroneous
motion signals at points of overlapping form. Intrinsic-extrinsic region boundaries are indicated by local T-junctions of
possibly any orientation and spatial configuration. Such junctions generate strong localized feature tracking signals that
inject erroneous motion directions into the integration process. We describe a simple local mechanism of excitatory form-motion
interaction that modifies spurious motion cues at T-junctions. In concert with local competitive-cooperative mechanisms of
the motion pathway the motion signals are subsequently segregated into coherent representations of moving shapes. Computer
simulations demonstrate the competency of the proposed neural model. 相似文献
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The time-to-passage (TTP; i.e., the time) until an object passes an observer is optically specified by global tau, a variable that operates on the expansion rate of the angle subtended by an object relative to the observer's heading. M. K. Kaiser and L. Mowafy (1993) provided evidence for observers' sensitivity to global tau in a 3-D cloud of point lights. This interpretation is challenged, and it is suggested that TTP judgments are based on a related but much simpler variable, the image velocity of the object. The present study reexamined several factors that are relevant for the extraction of global tau. When global tau and image velocity were brought into conflict by varying the lateral offsets of the targets, observers showed a strong tendency to rely on the latter variable. Other factors that are supposed to affect TTP judgments only if observers relied on global tau, such as flow-field density and gaze-movement angle, did not affect performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献