The presence of perchlorate (ClO(4) (-)) in some U.S. drinking water supplies has raised concern about potential adverse thyroidal health effects, because ClO(4) (-) is known to competitively inhibit iodide uptake at the sodium iodide symporter (NIS). Humans are nutritionally and environmentally exposed to other competitive inhibitors of iodide uptake, including thiocyanate (SCN(-)) and nitrate (NO(3) (-)). The joint inhibiting effects of these three anions was studied by exposing Chinese hamster ovary cells stably expressing human NIS to varying concentrations of each anion separately, and in combination, and conducting measurements of (125)I(-) uptake. The entire data set was fit to a single Hill equation using maximum likelihood. The relative potency of ClO(4) (-) to inhibit (125)I(-) uptake at the NIS was found to be 15, 30 and 240 times that of SCN(-), I(-), and NO(3) (-) respectively on a molar concentration basis, with no evidence of synergism. These results are consistent with a common mode of action by these anions of simple competitive interaction, in which a concentration of any one of ClO(4) (-) SCN(-), and NO(3) (-), occurring either individually or as part of a mixture of the three anions, is indistinguishable from a concentration or dilution of either one of the remaining two ions in inhibiting iodine uptake at the NIS.

Objective: MicroRNAs (miRNAs) are small endogenous noncoding RNAs that pair with target messengers regulating gene expression. Changes in miRNA levels occur in thyroid cancer. Fine-needle aspiration (FNA) with cytological evaluation is the most reliable tool for malignancy prediction in thyroid nodules, but cytological diagnosis remains undetermined for 20% of nodules. Design: In this study, we evaluated the expression of seven miRNAs in benign nodules, papillary thyroid carcinomas (PTCs), and undetermined nodules at FNA. Methods: The prospective study included 141 samples obtained by FNA of thyroid nodules from 138 patients. miRNA expression was evaluated by quantitative RT-PCR and statistical analysis of data was performed. Genetic analysis of codon 600 of BRAF gene was also performed. Results: Using data mining techniques, we obtained a criterion to classify a nodule as benign or malignant on the basis of miRNA expression. The decision model based on the expression of miR-146b, miR-155, and miR-221 was valid for 86/88 nodules with determined cytology (97.73%), and adopting cross-validation techniques we obtained a reliability of 78.41%. The prediction was valid for 31/53 undetermined nodules with 16 false-positive and six false-negative predictions. The mutated form V600E of BRAF gene was demonstrated in 19/43 PTCs and in 1/53 undetermined nodules. Conclusions: The expression profiles of three miRNAs allowed us to distinguish benign from PTC starting from FNA. When the assay was applied to discriminate thyroid nodules with undetermined cytology, a low sensitivity and specificity despite the low number of false-negative predictions was obtained, limiting the practical interest of the method.

Genetic analysis of the DUOX2 gene was performed in 11 children with organification defect. Two new mutations (Y1150C and A728T) and the deletion S965FsX994 were responsible for the deficit in the organification process and the phenotypes. Three polymorphisms (H678R, P982A, and R701Q) were identified.

Biofortification of vegetables with iodine provides a mild but significative increase in UI concentration and, together with the habitual use of iodized salt, may contribute to improve the iodine nutritional status of the population without risks of iodine excess.

In this study, we aimed at establishing whether two previously identified thyroid disruptors, the insecticide 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and Aroclor 1254 (a complex mixture of polychlorinated water), may inhibit thyrotropin (TSH) receptor (TSHr) activity. DDT and Aroclor 1254 were shown to inhibit both the basal and bovine TSH (bTSH)-stimulated accumulation of cAMP in Chinese hamster ovary (CHO)-K1 cells stably transfected with the TSHr. Furthermore, both DDT and Aroclor 1254 did indeed prevent cAMP accumulation, as induced by the constitutive activity of a point mutant TSHr(I486M) transiently transfected in African green monkey kidney fibroblast (COS)-7 cells. Neither trypsin digestion of the extracellular domain (ECD) nor deletion of the ECD in a mutant TSHr trunk transiently transfected in COS-7 cells counteracted the inhibitory activity of DDT and Aroclor 1254. DDT exerted a weak inhibitory activity against forskolin in both CHO-K1 and COS-7 cells, whereas it was nil against the agonists dopamine and 5Ј-(N-ethyl-carboxamido)-adenosine (NECA) in CHO cells stably transfected with the dopamine D 1 receptor and in COS-7 cells transiently transfected with the adenosine type 2a receptor (A 2 a) receptor. Furthermore, DDT was inactive against the stimulation by isoproterenol of the endogenously expressed ␤ 2 adrenergic receptor in COS-7 cells. Conversely, Aroclor 1254 inhibited completely forskolin activity in CHO-K1 cells but not in COS-7 cells. Furthermore, it did not prevent accumulation of cAMP as induced by NECA in A 2 a transfected cells. The analog of DDT, diphenylethylene, was inactive against bTSH-induced increase in cAMP in CHO-K1 cells stably transfected with the TSHr. We interpreted these results as indicating that DDT and possibly Aroclor 1254 may have an uncompetitive inverse agonist activity for the TSHr.

Plants are a poor source of iodine, an essential micronutrient for human health. Several attempts of iodine biofortification of crops have been carried out, but the scarce knowledge on the physiology of iodine in plants makes results often contradictory and not generalizable. In this work, we used a molecular approach to investigate how the ability of a plant to accumulate iodine can be influenced by different mechanisms. In particular, we demonstrated that the iodine content in Arabidopsis thaliana can be increased either by facilitating its uptake with the overexpression of the human sodium-iodide symporter (NIS) or through the reduction of its volatilization by knocking-out HOL-1, a halide methyltransferase. Our experiments show that the iodine content in plants results from a balance between intake and retention. A correct manipulation of this mechanism could improve iodine biofortification of crops and prevent the release of the ozone layer-threatening methyl iodide into the atmosphere.

We performed a genetic analysis in one child with CH and a eutopic thyroid gland. Two new mutations in DUOX2 gene responsible for the partial deficit in the organification process were identified.

This study was designed to assess the relationship between mutations in the FSH receptor (FSHr) gene and polycystic ovary syndrome (PCOS) in Italian women. The study population included 50 patients with PCOS and 50 age- and body mass index (BMI)-matched controls. A complete anthropometrical, hormonal and pelvic ultrasonographic evaluation was performed in all subjects. Genomic DNA was extracted from peripheral lymphocytes and then each exon of the FSHr gene was amplified by PCR. The mutation identified was cloned and the functional properties were studied after transient expression in COS-7 cells. Direct sequencing of exons 1-10 of the FSHr gene revealed the presence of a heterozygous AAT/ATT mutation affecting the isoleucine residue at position 411, which was replaced by an asparagine, in the second transmembrane segment (I411N). This mutation was only found in one woman with PCOS and not in her parents. This mutation was not present in 50 age and BMI controls and in another 150 women not affected by PCOS. The functional study after transient expression in COS-7 cells revealed that this I411N had similar functional characteristics with respect to the wild type FSHr (wtFSHr). Genetic analyses of polymorphisms in the human FSHr gene were also performed. All 50 women with PCOS harbored the A307T polymorphic variant, 56% harbored N680S, 30% S680S and 14% N680N polymorphisms. In conclusion, the present study demonstrates that mutations of the FSHr gene are rare in Italian women. The only mutation that we found does not appear to have any pathophysiological significance in PCOS.