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

An experiment on the perceived efficacy of fear-based messages in online roulette

The current study examined the emotional and cognitive evaluations as well as the perceived efficacy of fear-based, text-only pop-up messages. The pop-up messages were presented when viewing a 3-minute prerecorded video of online roulette play. Fifty-nine people who gamble online viewed both low- and high-threat messages that reflected, by random assignment, either the financial (n= 27) or social (n= 32) consequences of gambling. Participants then reported their emotional and cognitive evaluations of the messages, as well as their perceived efficacy to facilitate responsible gambling. Eye-tracking was used as an objective measure of attention to the message. A 2 (message theme: social, financial) x 2 (threat level: low, high) mixed-model ANOVA was used to examine the evaluations and efficacy of the messages. The main effects of message theme/threat level were not significant. The 2 × 2 interaction for the outcome of overall effectiveness was significant, whereby the high-threat and social message combination was rated more effective than other combinations. For eye-tracking, there were no significant findings. The results suggest that fear-based social messaging may be more effective than non-fear inducing or financially-oriented messages. Further research can explore if messages that are perceived to be effective likewise lead to lower-risk gambling.</p