Antimicrobial Electrospun Membranes of Selp/Ag Composites

Silk-elastin-like proteins (SELPs) are a new class of bioinspired, biologically synthesized block copolymers, composed of silk and elastin repeating units. SELP electrospun fibre mats show potential for application as wound dressings for skin regeneration. In this work, antimicrobial nanofibrous mats were produced by electrospinning SELP solutions containing different concentrations of silver nitrate without addition of reducing agents. The SELP/Ag composite materials demonstrated antimicrobial activity against both Gram– and Gram+ bacteria. Furthermore, the SELP/Ag composite materials showed no cytotoxicity against normal human skin fibroblasts.This work was supported by FCT/MEC through Portuguese funds (PIDDAC) - PEst-OE/BIA/UI4050/2014, PEST-C/FIS/UI607/2011, Matepro - NORTE-07-0124-FEDER-000037. RM, AC and VS, acknowledge FCT for SFRH-BPD/86470/2012, SFRH/BD/75882/2011 and SFRH/BPD/63148/2009 grants, respectively. The authors also thank support from the COST Action MP1206 “Electrospun Nano-fibres for bio inspired composite materials and innovative industrial applications”

Enhanced notch signaling modulates unproductive revascularization in response to nitric oxide-angiopoietin signaling in a mouse model of peripheral ischemia

IntroductionArteriolargenesis can be induced by concomitant stimulation of nitric Oxide (NO)‐Angiopoietin receptor (Tie)‐Vascular Endothelial Growth Factor (VEGF) signaling in the rat mesentery angiogenesis assay. We hypothesized that the same combination of exogenously added growth factors would also have a positive impact on arteriolargenesis and, consequently, the recovery of blood flow in a model of unilateral hindlimb ischemia.Results and MethodsNO‐Tie mice had faster blood flow recovery compared to control mice, as assessed by laser speckle imaging. There was no change in capillary density within the ischemic muscles, but arteriole density was higher in NO‐Tie mice. Given the previously documented beneficial effect of VEGF signaling, we tested whether NO‐Tie‐VEGF mice would show further improvement. Surprisingly, these mice recovered no differently from control, arteriole density was similar and capillary density was lower. Dll4 is a driver of arterial specification, so we hypothesized that Notch1 expression would be involved in arteriolargenesis. There was a significant upregulation of Notch1 transcripts in NO‐Tie‐VEGF compared with NO‐Tie mice. Using soluble Dll4 (sDll4), we stimulated Notch signaling in the ischemic muscles of mice. NO‐Tie‐sDll4 mice had significantly increased capillary and arteriole densities, but impaired blood flow recovery.ConclusionThese results suggest that Dll4 activation early on in revascularization can lead to unproductive angiogenesis and arteriolargenesis, despite increased vascular densities. These results suggest spatial and temporal balance of growth factors needs to be perfected for ideal functional and anatomical revascularisation

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13