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

Triagem auditiva neonatal: motivos da evasão das famílias no processo de detecção precoce Newborn hearing screening: reasons for the evasion of families in the process of early detection

OBJETIVO: Analisar os motivos da evasão familiar no programa de triagem auditiva neonatal realizado em um hospital público e correlacioná-los com a distribuição demográfica das famílias e as características do programa. MÉTODOS: Participaram 132 famílias, de um total de 739 contatadas, cujos filhos nasceram em uma maternidade no interior do estado de São Paulo de outubro/2003 a dezembro/2005 e que não haviam comparecido para a realização do teste ou reteste da triagem auditiva neonatal. Foi aplicado um questionário de levantamento das causas de evasão, contendo perguntas relacionadas à triagem auditiva, nível de escolaridade e profissão dos pais e também sobre a audição e o desenvolvimento de linguagem da criança. RESULTADOS: Realizou-se a aplicação do questionário com 132 famílias (17,86%); com as demais não foi obtido contato. Deste total, 82 haviam faltado na primeira etapa da triagem auditiva (teste) e 50 não haviam retornado para realização do reteste. Os motivos mais frequentes para justificar a evasão foram o desinteresse e a dificuldade em conciliar o agendamento com a rotina familiar. Não houve associação entre os motivos da evasão e o nível de escolaridade e ocupação dos pais, nem com o profissional que realizou a orientação acerca da triagem auditiva. Não foi referido nenhum caso de alteração auditiva, nem de atraso significativo no desenvolvimento da linguagem. CONCLUSÃO: Os motivos da evasão familiar independem de variáveis voltadas à família e à dinâmica do programa de triagem auditiva.<br>PURPOSE: To analyze the reasons for evasion of the families from the newborn hearing screening program conducted at a public hospital, and to correlate them with the demographic distribution of the families and the characteristics of the program. METHODS: Participants were 132 families, from a total of 739 contacted, whose children had been born in a maternity hospital in the interior of the state of São Paulo, Brazil, from October/2003 to December/2005, and who had not showed up for the newborn hearing screening test or retest. A questionnaire regarding the causes for evasion was applied, asking information related to the newborn hearing screening, level of education and occupation of parents, and the child's hearing and language development. RESULTS: The questionnaire was applied to 132 families (17.86%); contact was not possible with the other families. From this total, 82 had not shown up in the first stage of the hearing screening (test), and 50 had not returned for retest. The most frequently provided reasons for the evasion were lack of interest and scheduling conflicts. There was no association between the reasons for the evasion and parent's education level and occupation, nor with the professional who provided orientation regarding the newborn hearing screening. Hearing alteration were not referred, as well as significant language development delay. CONCLUSION: The reasons for family evasion are independent from variables related to the family and the dynamics of the hearing screening program