Iodine status in schoolchildren living in northeast Italy: the importance of iodized-salt use and milk consumption.

BACKGROUND: The aims of the study were: (i) to determine iodine status of schoolchildren living in northeast Italy; (ii) to assess dietary habits and iodine status and (iii) to investigate the level of knowledge concerning iodine sufficiency and ways to ameliorate iodine status. METHODS: One thousand three hundred seventy-five consecutive 12-13 year-old completed questionnaires collecting demographic data and information about the use of iodized salt and food frequency habits. Iodine concentration in urine samples (UIC) and in commercially available milk samples has been measured. RESULTS: The median UIC was found to be 81 µg/l (95% confidence interval (CI) 74-87); 40% of the subjects had an UIC of ≥ 100 µg/l. Iodine deficiency was prevalent in subjects living in hilly areas. Median iodine concentration in milk was 264 µg/l. Only the combined use of iodized salt plus daily milk normalized UIC, resulting into a median value of 108 µg/l. A logistic regression model confirmed independent associations between low UIC and low intake of milk, use of non-iodized salt and geographical location (P<0.0001). Only 45% of the subjects were aware of the importance of iodine. CONCLUSIONS: Northeast Italy is still characterized by mild iodine deficiency. An adequate iodine status was achieved only when iodized salt was combined with daily milk intake. The national iodine prophylaxis program has led to greater consumption of iodized salt and, it is now used in 60-70% of the Italian households. The low level of awareness highlights the need for public programs to promote knowledge and efforts to improve iodine status.

Effects of selenium supplementation on the natural course of autoimmune thyroiditis: a short review.

Selenium (Se) is an important element that exerts its effects on the selenoproteins. It is an essential component of the glutathione peroxidase enzymes, which have anti-oxidant and anti-inflammatory properties, and a component of iodothyronine selenodeiodinases, which catalyze the extrathyroid production of T3 from T4. Se is important to several aspects of thyroid homeostasis and may influence the natural course of thyroid diseases such as autoimmune thyroiditis (AIT). This review analyzes the effects of Se supplementation in patients with AIT, based on the studies published on this issue to date.

ERP and fMRI correlates of endogenous and exogenous focusing of visual-spatial attention.

The aim of this study was to investigate the neural correlates of the functional distinction underlying attentional mechanisms of endogenous-sustained and exogenous-transient spatial selection. We recorded event related potentials (ERPs) and used functional magnetic resonance imaging (fMRI) in separate experiments while subjects performed a simple reaction time (RT) to the same visual stimulus displayed to one of several field locations. Endogenous-sustained or exogenous-transient focusing of attention onto target location were obtained by presenting the stimulus in blocks of same-point vs. randomised-point trials, respectively. Same-point stimuli yielded overall faster RT than randomised stimuli, indicating a facilitating effect of endogenous-sustained spatial attention on the perceptual processing of the impending stimulus. Moreover, same-point vs. randomised presentations revealed significant increases in the fMRI signal in the bilateral lingual and fusiform gyri as well as in the right calcarine sulcus, in conjunction with a larger amplitude of the posterior P1 component of ERPs, but no modulation of the amplitude of the N1 component. Rather, a larger amplitude of N1 was found in the reverse contrast, randomised minus same-point trials, which revealed increases in the fMRI signal along the posterior left superior frontal sulcus and bilaterally in the superior precuneus. These findings indicate that N1 indexes exogenous orienting of attention and is likely to represent the activity of frontal and parietal components of the attention network involved in eliciting attention changes. In contrast, the effects of those changes, resulting in a modulation of activation in visual occipital areas, are indexed by P1.

Restricted intraindividual urinary iodine concentration variability in nonfasting subjects.

OBJECTIVE: Individual urinary iodine concentration (UIC) reflects iodine intake over a short time prior to sampling. Since eating habits are relatively constant in single subjects, UIC should be relatively constant in a given individual. The aim of our study was to verify this hypothesis by assessing UIC in repeated single urine samples from a group of healthy subjects. DESIGN AND SETTING: A prospective sequential investigation was performed in 131 volunteer health workers or students recruited in our University hospital. INTERVENTIONS: Single urine samples were taken in a nonfasting state, between 0900 and 1100 hours. Group 1 was composed by 131 subjects who collected one urine sample. Group 2 was composed by 11 subjects of the group 1, who collected multiple repeated urine samples (as a whole 158 urine samples, mean 14 samples each). UIC mean+/-s.d., median and coefficient of variation (CV%) was measured in both groups. RESULTS: Interindividual UIC variation was wide, UIC ranging from 21 to 382 microg/l, mean 136+/-84 microg/l, median 124 microg/l, CV 62%. Also in the 11 subjects repeatedly sampling there were considerable differences among individual UIC average levels (ranging from 37+/-15 to 221+/-91 microg/l). However, in this second group, the intraindividual variation was considerably restricted (CV% 36). CONCLUSIONS: The present study shows that in a nonfasting state in mid-morning UIC is more stable from day to day in a single subject, depending on his eating habits, than in various subjects. Thus, a single urine sample even in nonfasting state may give some rough information about the individual's iodine status.

Milk represents an important source of iodine in schoolchildren of the Veneto region, Italy.

The aim of the present study is to evaluate the relationships between urinary iodine concentration (UIC) and the intake of milk and other foods, in a group of school children of the Veneto region, in North East Italy. A questionnaire, concerning the daily intake of milk, yoghurt, cheese and other animal foodstuffs, was distributed to 233 schoolchildren aged between 11 and 15 yr. The use of iodized salt was also investigated. UIC was measured in a casual urine sample of all children investigated. The iodine content of 28 samples of milk and of 13 samples of yoghurt, bought during the summer in shops of the same area, was measured. UIC values ranged between 25 and 436 microg/l, median value was 140 microg/l, mean value 149+/-78 microg/l. The median iodine content of milk and yoghurt were 278 microg/l and 216 microg/l, respectively. With regard to dietary habits, about 70% of the children took 200 ml of milk or more per day, which corresponds to a daily intake of iodine ranging between 50 and 100 microg a day. About 30% of schoolchildren used iodized salt. A highly significant correlation between UIC and milk intake was observed (p=0.0005), while the relationship was poor or absent in the case of both intake of other foodstuffs and use of iodized salt (p=0.38). In conclusion, the results of the study document the very important role of cows' milk as a source of iodine in childhood in the Veneto region, Italy.

Normal values for thyroid ultrasonography, goiter prevalence and urinary iodine concentration in schoolchildren of the Veneto Region, Italy.

Goiter prevalence in school-age children and median urinary iodine concentration (UIC) are the main indicators of iodine deficiency in a population. In areas of mild iodine deficiency, where goiters are small, ultrasound is preferable to physical examination to estimate goiter prevalence. The World Health Organization (WHO) has adopted thyroid volume ultrasonography results from a survey of European schoolchildren as an international reference, but these values have recently been questioned. The aims of the study were: a) to determine regional normal echographic reference values of thyroid volume in children aged between 11 and 14 yr in the Veneto Region, in North-East Italy; b) to determine goiter prevalence by physical and ultrasonographic examination; c) to determine UIC in this section of the population. A cross-sectional study was carried out on 1730 schoolchildren, aged between 11 and 14, living in towns in low-lying areas, in the valleys of the pre-Alps and in the mountains between 600 and 1200 m. Thyroid volume was evaluated by inspection and palpation using the WHO criteria. In 560 children thyroid volume was determined by ultrasound. UIC was measured in 1368 children. On physical examination a grade I goiter was found in 7.5% of children. No goiter grade II or grade III was found. The regional thyroid volume reference values by ultrasonography were similar, or slightly lower (5-20%), to the corresponding WHO reference values. Mean UIC was 148 +/- 110 microg/l, with no difference between lowlands and uplands; UIC values less than 100 microg/l were found in about 30-35% of the children. UIC was higher in children using iodized salt than in non-users. No correlation was found between thyroid volume by ultrasonography and UIC. Thyroid volume was found to be bigger in upland children than in those in low-lying areas, probably because of low iodine intake in people living in the mountains in previous generations. This data show that Veneto is not a iodine-deficient area, with no presence of endemic goiter. However, the great number of children with a UIC of less than 100 microg/l also suggests the use of iodized salt in the Veneto Region.

What exactly is extinguished in unilateral visual extinction? Neurophysiological evidence.

We propose a model of unilateral visual extinction following right hemisphere lesions based on competition between contralesional and ipsilesional input to access a decision centre located in the left hemisphere. During bilateral presentations, the contralesional signal is on average less likely to activate the decision centre than the ipsilesional signal. This is because an intra-hemispheric lack of top-down attentional influences and an inter-hemispheric impairment of callosal transmission delay and/or weaken the contralesional input. Here we provide behavioural as well as event-related potential evidence for both these impairments. Finally, we argue that an essential prerequisite for contralesional extinction is the presence of a restricted general attentional capacity which often follows large right hemisphere damage.

Human vasculogenesis ex vivo: embryonal aorta as a tool for isolation of endothelial cell progenitors.

SUMMARY: Vasculogenesis, the de novo formation of new blood vessels from undifferentiated precursor cells or angioblasts, has been studied with experimental in vivo and ex vivo animal models, but its mechanism is poorly understood, particularly in humans. We used the aortic ring assay to investigate the angioforming capacity of aortic explants from 11- to 12-week-old human embryos. After being embedded in collagen gels, the aorta rings produced branching capillary-like structures formed by mesenchymal spindle cells that lined a capillary-like lumen and expressed markers of endothelial differentiation (CD31, CD34, von Willebrand factor [vWF], and fms-like tyrosine kinase-1 [Flk-1]/vascular endothelial growth factor receptor 2 [VEGFR2]). The cell linings of these structures showed ultrastructural evidence of endothelial differentiation. The neovascular proliferation occurred primarily in the outer aspects of aortic rings, thus suggesting that the new vessels mainly arose from immature endothelial precursor cells localized in the outer layer of the aortic stroma, ie, a process of vasculogenesis rather than angiogenesis. The undifferentiated mesenchymal cells (CD34+/CD31-), isolated and cultured on collagen-fibronectin, differentiated into endothelial cells expressing CD31 and vWF. Furthermore, the CD34+/CD31+ cells were capable of forming a network of capillary-like structures when cultured on Matrigel. This is the first reported study showing the ex vivo formation of human microvessels by vasculogenesis. Our findings indicate that the human embryonic aorta is a rich source of CD34+/CD31- endothelial progenitor cells (angioblasts), and this information may prove valuable in studies of vascular regeneration and tissue bioengineering.

Neural sources of focused attention in visual search.

Previous studies of visual search in humans using event-related potentials (ERPs) have revealed an ERP component called 'N2pc' (180-280 ms) that reflects the focusing of attention onto potential target items in the search array. The present study was designed to localize the neuroanatomical sources of this component by means of magnetoencephalographic (MEG) recordings, which provide greater spatial precision than ERP recordings. MEG recordings were obtained with an array of 148 magnetometers from six normal adult subjects, one of whom was tested in multiple sessions so that both single-subject and group analyses could be performed. Source localization procedures revealed that the N2pc is composed of two distinct neural responses, an early parietal source (180-200 ms) and a later occipito-temporal source (220-240 ms). These findings are consistent with the proposal that parietal areas are used to initiate a shift of attention within a visual search array and that the focusing of attention is implemented by extrastriate areas of the occipital and inferior temporal cortex.

A novel mutation in the thyrotropin (TSH) receptor gene causing loss of TSH binding but constitutive receptor activation in a family with resistance to TSH.

Resistance to TSH is a syndrome due to reduced responsiveness of the thyroid gland to biologically active TSH. Inactivating mutations of the TSH receptor (TSH-R) have been detected in several cases of resistance to TSH, both partial and complete, sporadic and familial. In this study, we describe a family with the presence of resistance to TSH responsible for euthyroid hyperthyrotropinemia in two siblings from consanguineous parents. By direct sequencing of the TSH receptor gene, we identified a new mutation responsible for the substitution of an arginine with a cysteine at position 310, in the extracellular domain of the TSH-R. The mutation was homozygous in two brothers; heterozygous in both parents, an uncle, and an unaffected brother; and absent in the other unaffected brother. When stably transfected in Chinese hamster ovary cells, the Cys310 mutant TSH-R showed loss of response to TSH in terms of cAMP stimulation. However, a constitutive activity in terms of basal cAMP production was detected in the Cys310 mutant, compared with the wild-type TSH-R. Our data suggest that such a Cys310 TSH-R mutant may determine both the TSH resistance and the clinical euthyroidism detected in this family.

Electrophysiological correlates of conscious vision: evidence from unilateral extinction.

To study the electrophysiological correlates of conscious vision, we recorded event-related potentials (ERPs) in a patient with partial unilateral visual extinction as a result of right-hemisphere damage. When, following bilateral presentations, contralesional stimuli were not perceived, there was an absence of the early attention-sensitive P1 (80-120 msec) and N1 (140-180 msec) components of the ERP response. In contrast, following unilateral presentations, or in those bilateral presentations in which contralesional stimuli were perceived (about 60%), these ERP components were present. These results provide novel evidence that extinction involves the stage of early focusing of attention and that the P1 and N1 components of visual ERPs are reliable physiological correlates of conscious vision.

Serum thyroglobulin measurements in differentiated thyroid cancer.

In pathological states, the serum thyroglobulin (Tg) concentrations are generally high. Therefore, a serum assay of Tg levels is not useful for the differential diagnosis between benign or malignant disease in the preoperative period. Serum Tg measurements are a suitable marker in the follow-up of patients with differentiated thyroid carcinoma (DTC) during the postoperative period. After total thyroidectomy, serum Tg concentrations were found to be undetectable in subjects without evidence of residual thyroid tissue or metastases; however, detectable serum Tg levels in subjects on and off thyroid hormone suppressive therapy indicate the presence of residual or metastatic thyroid tissue. An increase in serum Tg levels during thyroid stimulating hormone (TSH) suppression indicates that further investigations are necessary.

Isolation and characterization of neural stem cells from the adult human olfactory bulb.

We have recently isolated stem cells deriving from the olfactory bulbs of adult patients undergoing particularly invasive neurosurgery. After improving our experimental conditions, we have now obtained neural stem cells according to clonal analysis. The cells can be expanded, established in continuous cell lines and differentiated into the three classical neuronal phenotypes (neurons, astrocytes, and oligodendrocytes). Also, after exposition to leukemia inhibitory factor, we are able to improve the number of neurons, an ideal biological source for transplantation in various neurodegenerative disorders.

A multimodality therapeutic approach in anaplastic thyroid carcinoma: study on 39 patients.

The aim of this study was to investigate the role of multimodality treatment in patients with anaplastic thyroid carcinoma. From 1992 to 1999, 39 consecutive patients with a histologically or cytologically proven anaplastic thyroid carcinoma were referred to the Thyroid Center of Padua General Hospital. There were 28 females and 11 males with a median age of 69 years (range 39-88 years). About one-third of patients had a history of preceeding nodular goiter. Two patients had areas of differentiated thyroid carcinoma at histological examination. Local disease was present in 26 patients while distant metastases, mainly to the lung, were present in 22 at diagnosis or quickly developed during the observation period in all the others except one. Thirty-two patients were previously untreated: 9 of them were in good general condition, 1 had limited lung metastases, and the tumor mass was considered resectable by the surgeon. These 9 patients were treated with cisplatin once a week and radiotherapy (RT) 36Gy in 18 fractions over three weeks, followed by total thyroidectomy (TT) and by further chemotherapy (CHT) with adriamycin and bleomycin in 4 patients. Seven patients, 3 with lung metastases at diagnosis, had undergone TT, followed by RT in 5, in another hospital and were subsequently referred to our center due to the presence of distant metastases. Therefore, a total of 16 patients (Group 1) was treated with TT, RT and CHT in various order. Nine patients with distant metastases at diagnosis (Group 2) received CHT; one of them had a disappearance of lung metastases and was then treated by TT and further CHT. Group 3 consisted of 14 elderly patients in poor general conditions; 4 of these received local RT, while the remaining did not receive any treatment. Four complete responses were seen in patients from Group 1, and 1 from Group 2. One patient without distant metastases at diagnosis is alive and free of disease 6 months after TT and adjuvant CHT, and 12 months after diagnosis. Three had long-term survival (14, 24, 27 months) with a disease-free interval of 6-8-10 months. The patient from Group 2 who was treated in a second time by TT is alive without disease after 60 months. Median survival rate was 11 months for Group 1, 5.7 months for Group 2 and 4 months for Group 3. In some patients multimodality treatment (TT, RT and CHT) is associated with increased survival. Nine out of 16 patients, who underwent surgery and complementary treatment, had no local progression. In all but one distant metastases developed, mainly in the lung, during or after post-surgical CHT. The best results were obtained in younger patients with less advanced disease. Early diagnosis is mandatory. Only a few patients responded to CHT, confirming that anaplastic thyroid carcinoma is often resistant to anticancer drugs. Our experience with combination modalities suggests that aggressive and appropriate combinations of RT, TT and CHT may provide some benefit in patients with anaplastic thyroid carcinoma. Preoperative CHT and RT may enhance surgical resectability of the primary tumor.

Fossa navicularis magna.

A notchlike bone defect in the basiocciput due to a prominent fossa navicularis was incidentally discovered in a patient referred for radiologic evaluation of sinusitis. MR images showed that the osseous defect was filled with lymphoid tissue of the pharyngeal tonsil. The occurrence of this anatomic variant is discussed, with reference to ancient anatomic works.

ERP and fMRI measures of visual spatial selective attention.

In two prior studies, we investigated the neural mechanisms of spatial attention using a combined event-related potential (ERP) and positron emission tomography (PET) approach (Heinze et al. [1994]: Nature 392:543-546; Mangun et al. [1997]: Hum Brain Mapp 5:273-279). Neural activations in extrastriate cortex were observed in the PET measures for attended stimuli, and these effects were related to attentional modulations in the ERPs at specific latencies. The present study used functional magnetic resonance imaging (fMRI) and ERPs in single subjects to investigate the intersubject variability in extrastriate spatial attention effects, and to qualitatively compare this to variations in ERP attention effects. Activations in single subjects replicated our prior group-averaged PET findings, showing attention-related increases in blood flow in the posterior fusiform and middle occipital gyri in the hemisphere contralateral to attended visual stimuli. All subjects showed attentional modulations of the occipital P1 component of the ERPs. These findings in single subjects demonstrate the consistency of extrastriate attention effects, and provide information about the feasibility of this approach for integration of electrical and functional imaging data.

Medullary thyroid carcinoma: clinical features and long-term follow-up of seventy-eight patients treated between 1969 and 1986.

This article describes the findings of a retrospective analysis of data obtained on 78 patients with medullary thyroid carcinoma (MTC), recorded between 1969 and 1986, and then followed at the Thyroid Center of Padua (Italy). The ages of the patients ranged between 15 and 89 years, with a median age of 45. The female to male (F:M) ratio was 2.9:1. All patients except 2 had total thyroidectomy. In 70 cases the tumor was of sporadic type; there were 3 familial non-multiple endocrine neoplasia (MEN) MTC; 3 MEN IIa; and 2 MEN IIb. The median duration of follow-up was 15.9 years (13 patients were followed up between 15 and 20 years, and 9 longer than 20). At diagnosis, the tumor was intrathyroid (stage I and II) in 31 patients, with local lymphnodes involved (stage III) in 41 patients, and with distant metastases (stage IV) in 6 patients. A total of 34 patients died (4 were at stage II at diagnosis, 26 at stage III, and 4 at stage IV); 4 of them died of unrelated causes, the others with tumor. The median survival rate of the deceased patients was 6 years (41% of these patients died within 3 years and 24% after more than 10 years); 76% of the deceased patients were older than 45 years at diagnosis. A total of 44 patients are still alive, 22 are alive free of disease (with follow-up between 10 and 24 years, median 14.2 years) and 22 are alive with disease (median follow-up 12.2 years). Only 30% of the patients of both these groups was older than 45 years at diagnosis. Survival is strongly related to tumor stage and to age at diagnosis, because only 8 of the 34 deceased patients were younger than 45 years (and 2 of them died of unrelated causes); moreover, patients who were treated at earlier stages of the disease had better prognosis. Survival rate at 10 and 20 years was 95% for patients with tumor limited to the thyroid, whereas it was 55% and 28.6%, respectively, for patients at stage III and IV. Bone metastases were correlated with worse prognosis than distant metastases only to soft tissues. The sex did not affect survival. None of the patients who had postoperative low serum calcitonin (CT) levels and no response to pentagastrin stimulation showed recurrences in the follow-up. In patients with postoperative elevated serum CT levels, recurrences of the tumor increased over time. However, 30% of these patients continued to show only elevated CT levels without evidence of the disease, even after 15 years.

Germline and somatic mutations of the RET proto-oncogene in apparently sporadic medullary thyroid carcinomas.

Medullary thyroid carcinomas (MTC) occur sporadically or as part of inherited multiple endocrine neoplasia (MEN) type 2 syndromes. To recognize misdiagnosed familial cases and to establish the frequency of somatic mutations, a series of 50 patients, clinically diagnosed with sporadic MTC, were analyzed for mutations in the RET proto-oncogene. The clinical management of the patient and of the family is different in the two cases. Germline mutations were detected in three independent cases, demonstrating that they were associated to familial MTC. The mutations affected exon 11 in two cases and exon 14 in one case. Somatic mutations were detected in eight patients (30%) and they were indicative of sporadic MTC. In seven cases the mutation affected codon 918 of exon 16 and in one case codon 634 in exon 11. No RET mutations were detected in the remaining patients. A different genetic and clinical management is proposed for individuals with a diagnosis of familial or sporadic MTC.