18 research outputs found
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
Italian Association of Clinical Endocrinologists (AME) position statement: a stepwise clinical approach to the diagnosis of gastroenteropancreatic neuroendocrine neoplasms
Presentation, diagnostic features and glucose handling in a monocentric series of insulinoma.
Chromosome translocation frequency after 131I thyroid remnant ablation: a comparison between rhTSH stimulation and prolonged LT4 withdrawal
Chromosome translocation frequency after radioiodine thyroid remnant ablation: a comparison between rhTSH stimulation and prolonged levothyroxine withdrawal
Abstract
BACKGROUND:
Thyroid remnant ablation of differentiated thyroid carcinoma (DTC) patients is traditionally performed after levothyroxine withdrawal. Recombinant human TSH (rhTSH) administration increases serum TSH levels without inducing hypothyroidism.
AIM:
The aim of the study was to investigate the frequency of chromosome translocations in DTC patients after the first (131)I therapeutic dose and compare the frequency of translocations between DTC patients off levothyroxine and those receiving rhTSH.
PATIENTS AND METHODS:
A total of 20 DTC patients were randomly assigned to levothyroxine withdrawal [(30 d) group A; n=10, nine women; mean age 48.5+/- 19.2 yr] or rhTSH injections [(0.9 mg im per 2 consecutive days) group B; n=10, eight women; mean age 50.4+/- 18.8 yr] before undergoing (131)I activity (3.7 GBq). The frequency of translocations in peripheral lymphocytes was analyzed by tricolor fluorescence in situ hybridization with whole-chromosome-specific probes for chromosomes 1, 4, and 8. Lymphocytes were stained routinely (about 500 each time).
RESULTS:
The two groups showed similar baseline translocation frequency. After (131)I administration, the total chromosomal translocation rate was significantly lower in group B than group A (P = 0.02). The frequency of translocations increased significantly in group A only (P = 0.01 vs. baseline). Rearrangement specifically involved chromosomes 4 and 8 (P = 0.02 vs. baseline).
CONCLUSIONS:
Our preliminary data show that in hypothyroid status (131)I ablation therapy induces a higher translocation rate, especially in chromosomes 4 and 8. This finding, in agreement with previous dosimetric reports, suggests that whereas inducing a low extrathyroid exposure, rhTSH reduces the potential risk of chromosomal aberration associated with blood irradiation