Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Making a Difference in ICT Research: Feminist Theorization of Sociomateriality and the Diffraction Methodology

Part 3: Hybrid Agency and the Performativity of TechnologyInternational audienceOver the last decade, sociomateriality appeared as a theme in IS research that has been interrogated with a variety of theoretical lenses. However, researchers have since raised methodological concerns regarding its application. This paper argues that a research methodology cannot be separated from either the theoretical lens that the research adopts or from its overarching purpose. Considering the broad range of theoretical lenses through which sociomateriality could be examined, this paper focuses on Barad’s theory of agential realism [25]. The paper provides a brief history of agential realism to shed light on the reasons behind IS researchers methodological difficulty and offers a diffraction methodology as a possible methodological guide to IS research adopting this lens. Implication for research is discussed