Prevalence of thyroid nodules in an occupationally radiation exposed group: a cross sectional study in an area with mild iodine deficiency

BACKGROUND: Thyroid nodules and thyroid cancer occur more frequently in people exposed to radiation for therapeutic purposes, and to nuclear fallout. Furthermore, it is known that a moderate degree of iodine deficiency may be responsible for an increased prevalence of thyroid nodules, while it is suspected that radiation exposure could induce changes in thyroid autoimmunity. The iodine intake of people resident in Bari, S. Italy, is mildly deficient, which could be presumed to cause a higher prevalence of thyroid pathology. This study was conducted to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation, in an area of mild iodine deficiency. METHODS: A cross-sectional study was designed to evaluate the prevalence of thyroid nodules in radiation exposed workers, compared with a stratified sample of non exposed workers. After giving written consent to participate in the study, all the recruited subjects (304 exposed and 419 non exposed volunteers) were interviewed to fill in an anamnestic questionnaire, and underwent a physical examination, ultrasound thyroid scan, serum determinations of fT3, fT4 and TSH, fine needle aspiration biopsy. The sample was subdivided into one group exposed to a determined quantity of radiation (detected by counter), one group exposed to an undetectable quantity of radiation, and the non exposed control group. RESULTS: The prevalence of thyroid nodules <1 cm in diameter, defined as incidentalomas, in the exposed group with detected doses, was 11.28% in males and 9.68% in females, while in the exposed group with undetectable dose the prevalence was 10.39% in males and 16.67% in females. In the non exposed group the prevalence of incidentalomas was 9.34% in males and 13.20% in females. These prevalences were not statistically different when analysed by a multiple test comparison with the bootstrap method and stratification for sex. Instead, the prevalence of thyroid nodules > 1 cm in diameter resulted statistically different in exposed and non exposed health staff: 18.68% in non exposed males vs exposed: 3.76% (determined dose) and 9.09% (undetectable dose) in males, and 20.30% in non exposed females versus 3.23% (detected dose) and 9.52% (undetectable dose) in exposed females. There was a higher proportion of healthy staff in the exposed group than in the non exposed: (80.45% vs 68.68% in males; 80.65% vs 57.87% in females). CONCLUSION: In our study, occupational exposure to radiation combined with mild iodine deficiency did not increase the risk of developing thyroid nodules. The statistically significant higher prevalence of thyroid nodules in the non exposed group could be explained by the high percentage (22%) of people with a familial history of, and hence a greater predisposition to, thyroid disease. The endemic condition of mild iodine deficiency, demonstrated in other studies, played a major role in determining the thyroid pathology in our study groups

Structural Modeling and DNA Binding Autoinhibition Analysis of Ergp55, a Critical Transcription Factor in Prostate Cancer

BACKGROUND: The Ergp55 protein belongs to Ets family of transcription factor. The Ets proteins are highly conserved in their DNA binding domain and involved in various development processes and regulation of cancer metabolism. To study the structure and DNA binding autoinhibition mechanism of Ergp55 protein, we have produced full length and smaller polypeptides of Ergp55 protein in E. coli and characterized using various biophysical techniques. RESULTS: The Ergp55 polypeptides contain large amount of α-helix and random coil structures as measured by circular dichorism spectroscopy. The full length Ergp55 forms a flexible and elongated molecule as revealed by molecular modeling, dynamics simulation and structural prediction algorithms. The binding analyses of Ergp55 polypeptides with target DNA sequences of E74 and cfos promoters indicate that longer fragments of Ergp55 (beyond the Ets domain) showed the evidence of auto-inhibition. This study also revealed the parts of Ergp55 protein that mediate auto-inhibition. SIGNIFICANCE: The current study will aid in designing the compounds that stabilize the inhibited form of Ergp55 and inhibit its binding to promoter DNA. It will contribute in the development of drugs targeting Ergp55 for the prostate cancer treatment

Conséquences des accidents radiologiques sur la santé mentale

Les catastrophes technologiques entraînent des troubles psycholo giques plus ou moins marqués et durables au sein des populations concernées. Cet article présente une revue des études épidémiologiques effectuées après les accidents de Three Mile Island, de Goiânia et de Tchernobyl pour en évaluer les conséquences psychologiques. Elle montre, dans des contextes culturels et accidentels très différents, une augmentation significative et durable des symptômes psychologiques dans différents groupes de population exposée, en faveur d'une détresse psychologique réelle. Il y a moins de résultats en faveur de l'existence d'une augmentation des syndromes psychiatriques, mais ces effets ont été beaucoup moins étudiés. Des groupes où les effets semblent avoir été plus marqués ont été identifiés tels les mères de jeunes enfants, les personnes relogées, les personnes ne pouvant bénéficier d'un soutien social de qualité ou en situation de précarité économique. La détresse psychologique observée peut favoriser le développement de troubles psychiatriques et donner lieu à des changements de comportement à l'égard de la santé. Des recherches restent nécessaires pour mieux préciser la nature des troubles rencontrés et leurs déterminants. Elles devraient s'appuyer sur la construction d'outils mieux adaptés notamment à l'évaluation des circonstances individuelles d'exposition et au diagnostic des effets

Integration of time as a description parameter in risk characterisation: Application to methyl mercury

Within the food risk assessment procedure, the characterisation of the risk consists in the comparison of the dietary exposure with a health based guidance value established in a previous step. One of the identified weaknesses of this comparison is that the time is not considered in the description. The aim of this paper is to describe the dietary exposure as a dynamic process determined by the accumulation phenomenon due to successive dietary intakes and by the pharmacokinetics ruling the elimination process in between intakes. Such a process belong to the category of piecewise deterministic Markov processes, which are widely used in a large variety of applications in insurance risk or in operations research, ranging from queuing systems to inventory/storage models. The inputs of the Kinetic Dietary Exposure Model are the probability distributions governing intakes and inter-intake times, as well as the half-life of the contaminant in the human body. In this paper, an application to methyl mercury is considered, with,exponential distributions for both the intakes and the inter-intake times, fitted from the French national consumption survey INCA, and a fixed half-life of 6 weeks for the elimination process. Within this framework, the process settles to a steady-state after approximately 5 years. A "Kinetic Tolerable Intake" (KTI), derived from the "Provisional Tolerable Weekly Intake" (PTWI) of 1.6 mu g/kg bw, is set to 14.6 mu g/kg and the probability of exceeding this threshold in the long run in the French adult female population is 1.22 E-15. (c) 2007 Elsevier Inc. All rights reserved

Nouvelles données sur l'urbanisme et l'histoire de la ville antique.: I. La ville haute

International audienc

Monterenzio (prov. de Bologne): la n\ue9cropole celto-\ue9trusque de Monterenzio Vecchio

Pr\ue9sentation des resultats de la cinqui\ue8me campagne de fouille dans ce lieu situ\ue9 dans l'apennin bolonais entre Bologne et Florence, sur la crete de Idice-Sillaro. Ont \ue9t\ue9 \ue9xplor\ue9s une n\ue9cropole celto-\ue9trusque (IVe et IIIe s. av. n.\ue8), une vaste couche d'habitat umbro-\ue9trusque datable du VI-Ve si\ue8cle av. n.\ue8. et la partie initiale d'un habitat de l'age du bronze r\ue9cent (XIIIe s. av. n.\ue8). Le mobilier recup\ue9r\ue9 est depos\ue9 au Mus\ue9e Arch\ue9ologique de Monterenzio (D. Vitali en est le directeur) o\uf9 interviennent les restaurateurs et documentalistes. Ici on \ue9labore les plans des tombes en Adobe Illustrator, et on \ue9tudie aussi les restes squ\ue9l\ue9tiques ainsi que les faunes offertes au milieu des mobiliers