Edinburgh Napier University

About: Edinburgh Napier University is a education organization based out in Edinburgh, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 2665 authors who have published 6859 publications receiving 175272 citations.

The Importance of Surface Area and Specific Reactivity in the Acute Pulmonary Inflammatory Response to Particles

Abstract: A range of different particle types cause excessive lung inflammation that is thought to play a role in the various types of pathology they produce. Recently attention has been focused on ultrafine particles and the phenomenon of rat lung overload. The authors and their collaborators have shown previously that the surface area metric drives the overload response. Acute inflammatory response following instillation of particles has also been used to evaluate hazard but has been criticized because of the non-physiological delivery and the problems of local overload. We have instilled a number of low-toxicity dusts of various particle sizes and assessed neutrophil influx into the lung at 18–24 h. The extent of inflammation has been shown to be a function of the surface area instilled. Since ultrafine particles present a ‘special’ case of high surface area, they are relatively inflammogenic. There is no evidence that ultrafine particles of carbon black, titanium dioxide or latex have any special reactivity in addition to their large surface area. We tested whether we could use this approach to model the reactivity of highly toxic dusts. Rats were instilled with either DQ12 quartz or aluminium lactate-treated DQ12 and, as anticipated, the high specific surface toxicity of DQ12 meant that it was much more inflammogenic than was predicted using the relationship described for low-toxicity dusts. By contrast, aluminium lactate-treated DQ12 fell on to the line of ‘low-toxicity’ dusts. This approach presents the possibility of modelling potential toxicity for nuisance dusts based on the inflammatory response of a given instilled surface area dose.

Smoke rings: social network analysis of friendship groups, smoking and drug-taking

Abstract: Social network analysis is applied at the first two time points of a longitudinal study which examines how smoking and drug use in adolescence is associated with social position within peer group structures. One hundred and fifty secondary second grade students in one school named up to six best friends. This allowed for the categorization of each adolescent as a group member, a group peripheral, or a relative isolate. It was found that risk-taking behaviour occurred across all social positions. At both time points of the study the behaviour of pupils on the periphery of peer groups reflected both the gender and the behaviour of the groups themselves. At the second time point of the study there were far more pupils on the periphery of risk-taking groups than on the periphery of non-risktaking groups. The relationship appears to verify that risk-taking and non-risk-taking behaviour is learned predominantly in the context of peer clusters, and that risk-taking peer clusters act as a greater focus of influen...

Coupled dynamics of dimethylsulfoniopropionate and dimethylsulfide cycling and the microbial food web in surface waters of the North Atlantic

Abstract: Oceanic dimethylsulfide (DMS), the main natural source of sulfur to the global atmosphere, is suggested to play a key role in the interaction between marine biota and climate. Its biochemical precursor is dimethylsulfoniopropionate (DMSP), a globally distributed, intracellular constituent in marine phytoplankton. During a multidisciplinary Lagrangian experiment in the subpolar North Atlantic, we determined the fluxes of DMSP and DMS through phytoplankton, microzooplankton, and bacterioplankton and compared them with concurrent carbon and sulfur fluxes through primary and secondary productions, grazing, and release and use of dissolved organic matter. We found that DMSP and derivatives contributed most (48-100%) of the sulfur fluxes and 5-15% of the carbon fluxes. Our findings highlight DMSP as a prominent player in pelagic biogeochemical pumps, especially as a major carrier in organic sulfur cycling. Also, our results illustrate the key role played by microzooplankton and heterotrophic bacteria (hence the microbial food web) in controlling the amount of phytoplanktonic DMSP that ultimately vents to the atmosphere in the form of DMS.

Histone acetylation regulates epithelial IL-8 release mediated by oxidative stress from environmental particles

Abstract: Increases in the levels of environmental particulate matter with a diameter of <10 μm diameter (PM10) in the air are associated with a variety of adverse health effects, particularly chronic lung a...