Serum heparan sulfate levels are elevated in endotoxemia

<p>Abstract</p> <p>Background</p> <p>Increased vascular permeability is a characteristic feature of sepsis which, in the past, has been ascribed exclusively to a malfunction of endothelial cells. However, recently it has become evident that the endothelial glycocalyx is of considerable importance concerning various aspects of vascular physiology, e.g. the vascular barrier and inflammation. Heparan sulfate, one of its essential components is characteristically traceable in blood, in case the endothelial glycocalyx is damaged or destroyed.</p> <p>Methods</p> <p>In 15 pigs we investigated whether the administration of endotoxin from gram-negative bacteria (Escherichia coli) results in increased serum levels of heparan sulfate, signalizing a shedding of the glycocalyx. In addition, markers of inflammation (white blood cell count, platelet count, tumour necrosis factor-α and interleukin-6) were evaluated over an observation period of 6 hours.</p> <p>Results</p> <p>Serum heparan sulfate concentrations significantly increased over time in the endotoxin group and were significantly elevated in comparison to the control group 6 hours after administration of endotoxin (p < 0.001). In the endotoxin group all markers of inflammation significantly changed during the time course.</p> <p>Conclusions</p> <p>The administration of bacterial endotoxin induced a significant rise in degradation products of the endothelial glycocalyx.</p

Kinetic modelling of competition and depletion of shared miRNAs by competing endogenous RNAs

Non-conding RNAs play a key role in the post-transcriptional regulation of mRNA translation and turnover in eukaryotes. miRNAs, in particular, interact with their target RNAs through protein-mediated, sequence-specific binding, giving rise to extended and highly heterogeneous miRNA-RNA interaction networks. Within such networks, competition to bind miRNAs can generate an effective positive coupling between their targets. Competing endogenous RNAs (ceRNAs) can in turn regulate each other through miRNA-mediated crosstalk. Albeit potentially weak, ceRNA interactions can occur both dynamically, affecting e.g. the regulatory clock, and at stationarity, in which case ceRNA networks as a whole can be implicated in the composition of the cell's proteome. Many features of ceRNA interactions, including the conditions under which they become significant, can be unraveled by mathematical and in silico models. We review the understanding of the ceRNA effect obtained within such frameworks, focusing on the methods employed to quantify it, its role in the processing of gene expression noise, and how network topology can determine its reach.Comment: review article, 29 pages, 7 figure

MV-modules

AbstractIn the present paper, we define the MV-modules over PMV-algebras. These are structures that naturally correspond to ℓu-modules over ℓu-rings. Fixing an ℓu-ring (R,υ), we prove the equivalence between the category of ℓu-modules over (R,υ) and the category of MV-modules over Γ(R,υ). We also introduce the truncated modules, that are MV-algebras endowed with an external multiplication defined for any element in the positive cone of an ℓu-ring and we prove the natural equivalence between MV-modules and truncated modules