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Aim:After in vivo implantation of cell-loaded devices, only the cells close to the capillaries can obtain nutrients to maintain their functions. It is known that factors secreted by stem cells, rather than stem cells themselves, are fundamental to guarantee new vascularization in the area of implant.Materials & methods:To investigate this possibility, we have grafted mice with Bilayer and Flowable Integra® scaffolds, loaded or not with human adipose-derived stem cells.Results:Our results support the therapeutic potential of human adipose-derived stem cells to induce new vascular networks of engineered organs and tissues.Conclusion:This finding suggests that our approach can help to form new vascular networks that allow sufficient vascularization of engineered organs and tissues in cases of difficult wound healing due to ischemic conditions.

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BackgroundStress involves alterations of brain functioning that may precipitate to mood disorders. The neurotrophin Brain Derived Neurotrophic Factor (BDNF) has recently been involved in stress-induced adaptation. BDNF is a key regulator of neuronal plasticity and adaptive processes. Regulation of BDNF is complex and may reflect not only stress-specific mechanisms but also hormonal and emotional responses. For this reason we used, as an animal model of stress, a fish whose brain organization is very similar to that of higher vertebrates, but is generally considered free of emotional reactions.ResultsWe provide a comprehensive characterization of BDNF gene in the Dicentrarchus labrax and its transcriptional, translational and post-translational regulation following acute stress. While total BDNF mRNA levels are unchanged, BDNF transcripts 1c and 1d resulted down regulated after acute stress. Acute stress induces also a significant increase in proBDNF levels and reduction in mature BDNF suggesting altered regulation of proBDNF proteolytic processing. Notably, we provide here the first evidence that fishes possess a simplified proteolytic regulation of BDNF since the pro28Kda form, generated by the SKI-1 protease in mammals, is absent in fishes because the cleavage site has first emerged in reptilians. Finally, we show that the proBDNF/totBDNF ratio is a highly predictive novel quantitative biomarker to detect stress in fishes with sensitivity = 100%, specificity = 87%, and Negative Predictive Value = 100%.ConclusionThe high predictivity of proBDNF/totBDNF ratio for stress in lower vertebrates indicates that processing of BDNF is a central mechanism in adaptation to stress and predicts that a similar regulation of pro/mature BDNF has likely been conserved throughout evolution of vertebrates from fish to man.

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We have considered nanoparticles (NPs) of Fe, Co and Ni, three transition metals sharing similar chemical properties. NP dissolution, conducted by radioactive tracer method and inductively coupled plasma mass spectrometry, indicated that NiNPs and FeNPs released in the medium a much smaller amount of ions than that released by Co NPs. The two considered methodological approaches, however, gave comparable but not identical results. All NPs are readily internalized by the cells, but their quantity inside the cells is less than 5%. Cytotoxicity and gene expression experiments were performed on SKOV‐3 and U87 cells. In both cell lines, CoNPs and NiNPs were definitely more toxic than FeNPs. Real‐time polymerase chain reaction experiments aimed to evaluate modifications of the expression of genes involved in the cellular stress response (HSP70, MT2A), or susceptible to metal exposure (SDHB1 and MLL), or involved in specific cellular processes (caspase3, IQSEC1 and VMP1), gave different response patterns in the two cell lines. HSP70, for example, was highly upregulated by CoNPs and NiNPs, but only in SKOV‐3 cell lines. Overall, this work underlines the difficulties in predicting NP toxicological properties based only on their chemical characteristics. We, consequently, think that, at this stage of our knowledge, biological effects induced by metal‐based NPs should be examined on a case‐by‐case basis following studies on different in vitro models. Moreover, with the only exception of U87 exposed to Ni, our results suggest that metallic NPs have caused, on gene expression, similar effects to those caused by their corresponding ions. Copyright © 2015 The Authors. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.

Nef proteins of primate immunodeficiency viruses exert pleiotropic effects, such as enhanced endocytosis of CD4 and MHC-I cell surface molecules, perturbation of signal transduction cascades, and virion infectivity enhancement. Nef function intersects that of a number of cell kinases, including C kinases (PKCs) and Src-family kinases. Here the interaction of HIV-1 Nef with Rack1 (receptor for activated C kinase 1) is reported. Nef binds the Rack1 C-terminal moiety in a yeast two-hybrid system and in cell-free pull-down assays and copurifies with in vitro translated Rack1. Nef and Rack1 partially colocalize on the trans-Golgi network and plasma membranes. The presence of Rack1 doubles Nef phosphorylation by PKCs in vitro. Our data agree with the idea that Rack1 acts as a Nef intracellular docking site, bringing Nef and PKCs together. Other signal transduction or endocytosis proteins, in particular Src-like kinases, might meet Nef by intermediation of the Rack1 adaptor.