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Context: High concentrations of inspired oxygen contribute to the pathogenesis of neonatal bronchopulmonary dysplasia and adult acute respiratory distress syndrome. Animal models of hyperoxia-associated lung injury (HALI) are characterized by enhanced generation of reactive oxygen species (ROS) and an adaptive antioxidant response. ROS contribute to pathogenesis, partly through enhancing pro-inflammatory activity in macrophages. Uncoupling protein-2 (UCP2) is an inner mitochondrial membrane protein whose expression lowers mitochondrial superoxide () production. UCP2, therefore, has potential to contribute to antioxidant response. It is inducible in macrophages. Objectives and methods: We hypothesized that induction of UCP2 occurred in response to pulmonary hyperoxia in vivo and that expression localized to pulmonary macrophages. We then investigated mechanisms of UCP2 regulation in hyperoxia-exposed macrophages in vitro and correlated changing UCP2 expression with mitochondrial membrane potential (Δ ψm) and production. Results: UCP2 is induced in lungs of mice within 1 h of hyperoxia exposure. Induction occurs in pulmonary alveolar macrophages in vivo, and can be replicated in vitro in isolated macrophages. UCP2 mRNA does not change. UCP2 increases quickly after the first hyperoxia-induced burst of mitochondrial generation. Suppression of Δ ψm and mitochondrial production follow and persist while UCP2 is elevated. Discussion and conclusions: Induction of UCP2 is an early response to hyperoxia in pulmonary macrophages. The mechanism is post-transcriptional. UCP2 induction follows a transient rise in mitochondrial ROS generation. The subsequent falls in Δ ψm and mitochondrial support the notion that regulable UCP2 expression in macrophages acts to contain mitochondrial ROS generation. That, in turn, may limit inappropriate pro-inflammatory activation in HALI. [ABSTRACT FROM AUTHOR]

15-F2t-isoprostane (15-F2t-IsoP), an oxidation product of arachidonic acid (AA), affects vascular and platelet function; however, the bioactivity of other fatty acids oxidation products is unknown. This paper studied rat aortic vascular reactivity and human platelet aggregation in response to 14 oxidation products of AA, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and αα-linolenic acid (ALA) compared with 15-F2t-IsoP. It also compared the F2t-IsoPs profile in human platelets. EPA-derived 15-F3t-IsoP constricted rat aorta less than 15-F2t-IsoP, but none of the other oxidation products affected vascular reactivity. Only 15-F2t-IsoP (10−−4 M) directly affected platelet aggregation. 15-F3t-IsoP, ent-16-F1-phytoprostane (from ALA) and isofurans A and B (from AA) inhibited reversible aggregation to U46619. Unlike plasma, the platelet profile of F2-IsoP showed that 8-F2t-IsoP were higher than 15-F2t-IsoP. Unlike 15-F2t-IsoP, the test compounds derived from fatty acids oxidation did not affect vascular or platelet function. Elevated platelet 8-F2t-IsoP could limit 15-F2t-IsoP-induced aggregation under conditions of oxidant stress. [ABSTRACT FROM AUTHOR]

Three “postmortem” case studies in Florida provide insight into the emerging nature of online fraud on small financial institutions. Discourse between researchers, first responders, and law enforcement investigators reveal some of the inadequacies of current policies, protocols, and coordinated responses. This study seeks the causes of these inadequacies and recommends practical anti-phishing measures for puddle phishing targets.[Supplementary materials are available for this article. Go to the publisher's online edition of the Journal of Digital Forensic Practice for the following free supplemental resources: Postmortem Protocol and Phishing Incident Response Form.] [ABSTRACT FROM AUTHOR]

Copolymers of styrene (ST) and citraconic anhydride (α-methylmaleic anhydride) (CA) were prepared in a very polar solvent, N,N-dimethylformamide (DMF), at 50.0°C with AIBN. The monomer unit triad fractions were determined by 13C NMR in acetone-d6 solution. Non linear least square (NLLS) curve fitting was performed for the copolymerization models of the terminal model, the penultimate unit effect model, the complex participation model, the complex dissociation model, and the so-called comppen model. The theoretical equations for the ST-centered alternating triad mole fraction were fitted by NLLS minimization routine to the triad fraction data of the ST-CA copolymers and that of the ST-maleic anhydride (MA) copolymers prepared in identical polymerization conditions. It was found that for rigidly alternating copolymers of ST-MA, the difference among the copolymerization models disappeared and all models merged together. The difference among the copolymerization models were somewhat more apparent for less alternating copolymers of ST-CA copolymers. The sum of squares values indicated that the copolymerization models, which involved some complex participation, fit the data better with the comppen model. This was a combination of a complex participation and penultimate unit effects, which performed best. [ABSTRACT FROM AUTHOR]

Pays tribute to Terence Leslie Brian Wade, emeritus professor, Russian Studies, University of Strathclyde.

Pays tribute to Jean Fyfe, died in 2001. Jean's character; Jean's achievements.