In the nonconstant control case, we use Pontrygin’s
Maximum principle to derive necessary conditions for the optimal control of the pest. Then we demonstrated the analytical results by numerical analysis and characterized the effects of the parameter values on optimal strategy. (c) 2012 Elsevier Ltd. All rights reserved.”
“Reactive lipid hydroperoxides formed by lipoxygenases and cyclooxygenases can contribute to disease through cellular oxidative damage. Several selenoproteins have lipid hydroperoxidase activity, including glutathione peroxidase 4, thioredoxin reductase, and selenoprotein P (SelP). SelP is an selleck chemicals llc extracellular glycoprotein that functions both in selenium distribution and has an antioxidant activity. The major objective of this study was to determine if an SelP, at physiological concentrations and in selenium replete media, possessed hydroperoxidase activity directed at lipid hydroperoxides generated from the metabolism of arachidonic acid by 15-lipoxygenase-1 (15-LOX-1). An SelP displayed in vitro lipid hydroperoxidase activity selleck compound of 15-hydroperoxyeicosatetraenoic acid (15-HpETE), attenuated 15-HpETE oxidation in cellular assays, and in transcellular assay when 15-LOX-1 is metabolically active. These results suggest that an SelP can function as an antioxidant enzyme against reactive lipid intermediates
formed during inflammation, but an SelP has modest activity. Nevertheless, this effect may help protect cells against the oxidative damage induced
by these lipid metabolites. (C) 2010 Elsevier Ltd. All rights reserved.”
“Besides its prominent role in angiogenesis, the vascular endothelial growth factor (VEGF) also exerts important protective effects on neurons. In particular, mice expressing reduced levels of VEGF suffer from late-onset motor neuron degeneration, whereas VEGF delivery significantly delays motor neuron death in ALS mouse models, at least partly through neuroprotective effects. Additionally, VEGF protects dorsal root ganglion (DRG) neurons against paclitaxel-induced neurotoxicity. Here, we demonstrate that VEGF also protects DRG neurons against hyperglycemia-induced neuronal stress as a model of diabetes-induced peripheral Fluocinolone acetonide neuropathy. Specifically, VEGF decreased expression of the stress-related gene activating transcription factor 3 (ATF3) in DRG neurons isolated from streptozotocin-induced diabetic mice (ex vivo) and in isolated DRG neurons exposed to high glucose concentrations (in vitro). In vivo, local VEGF application also protected against paclitaxel- and diabetes-induced neuropathies without causing side effects. A small synthetic VEGF mimicking pentadecapeptide (QK) exerted similar effects on DRG cultures: the peptide reduced ATF3 expression in vitro and ex vivo in paclitaxel- and hyperglycemia-induced models of neuropathy to a similar extent as the full-length recombinant VEGF protein.