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In dual-energy CT, two CT datasets are acquired at different photon energy spectra. Because chemical elements vary in their attenuation properties at different photon energies, this allows to analyze the chemical composition of the imaged tissues and to extract or suppress individual chemical components. Dual-energy CT of the thorax makes use of this possibility in a variety of ways. The iodine distribution within the pulmonary parenchyma can be visualized to assess pulmonary perfusion. Inhaled noble gasses such as xenon and krypton are employed to image pulmonary ventilation. Iodine uptake of lung nodules has been investigated as a tool to distinguish between benign and malignant lesions and to assess tumor vascularity. Dual-energy CT myocardial perfusion imaging can visualize myocardial perfusion defects by displaying the iodine distribution within the myocardium. Dual-energy CT datasets also enable specific post-processing tools such as virtual non-contrast images, virtual non-calcium images, and virtual extrapolation to lower or higher photon energies, which have found promising applications for imaging the pulmonary vasculature, the aorta, and the spine. This chapter briefly reviews key technical aspects of dual-energy CT before discussing various established and investigational thoracic applications.

Perchlorate is regarded as a new emerging persistent inorganic environmental contaminant. It can result in important neurodevelopmental deficits and goiter in infants and children because of its inhibition of iodine uptake into the thyroid tissue. Furthermore, its presence in the human body can cause improper regulation of metabolism for adults. It is often used as ingredient in the production of fireworks. So fireworks display may influence the perchlorate levels in atmospheric particulate matter (PM). In this paper perchlorate was determined in air aerosol samples (Inhalable particulate matter (PM10) and larger particulate matter (PM10-100)) collected from two locations (Lanzhou City and Yuzhong County) in Gansu province over a month period (February 1rst to March 4th) during the Spring Festival (February 18th) in 2007 in order to study the effect of fireworks display on perchlorate in air aerosol. The results showed that different concentrations of perchlorate were detected in almost all samples, ranging from

The review highlights the effects of acute and chronic stress on thyroid metabolism. Special attention is paid to the influence of stress and the direct effects of glucocorticoids on the thyroid status, the activities of thyrocyte iodine uptake, oxidation and organification as well as peripheral metabolism of thyroid hormones (deposition and transport of thyroid hormones, deiodinase activities in different tissues). The role of stress in the development of thyroid pathology is analysed and charestiristic features of thyroid function alterations during impaired functioning of the pitiutary-adrenal system are established. The mechanisms of the stress-induced impairments in thyroid functions are of interest for further research, taking into consideration serious consequences of thyroid deficiency for the body, even in subclinical thyroid insufficiency.

Equal amounts of autonomous thyroid tissue were found with the same frequency before and after 40 years of age in eumetabolic patients in endemic goitre areas. A tentative diagnosis of thyroid autonomy can be made already in euthroid patients with an 80% accuracy by combined estimation of an equivalent of free thyroxine and iodine uptake. The equivalent is taken from determination of thyroid pertechnetate uptake by quantitative scan evaluation. Proof of autonomy is established by the suppression test which in a prolonged fractionated form also permits estimation of the amount of functioning autonomous tissue. There is a linear correlation of technetium thyroid uptake after suppression and the volume of autonomous thyroid tissue. As free thyroxine increases after iodine intake of sufficient amount and duration in proportion with the volume of autonomous tissue, prognosis appears possible: patients with autonomous thyroid tissue above a "critical" volume can be expected to develop hyperthyroidism in case of sufficient iodine uptake. Iodine salt prophylaxis however does not induce hyperthyroidism in patients below 50 years of age provided that the daily additional iodine intake does not exceed 100 micrograms.

Typical signs of so-called hyperthyroiditis are hyperthyroidism, low iodine uptake by the thyroid, absence of local, general or humoral signs of inflammation, and absence of significant antibody titres against thyroid tissue. These features are illustrated by the case report of a 51-year-old man. Since the course of hyperthyroidism is short and has a good prognosis, the importance of the diagnosis lies in avoiding unnecessary therapeutic measures. This cause of hyperthyroidism can be recognized only by including tests of intrathyroid iodine metabolism among diagnostic procedures.

Molecular imaging is the visualization, characterization, and measurement of biologic processes at the molecular and cellular levels in human beings and other living systems. In thyroid cancer, this includes imaging iodine transport, which is active in about 80% of well-differentiated thyroid malignancies. Iodine-124 imaging with positron emission tomography (I-124-PET) is ideal for this purpose because PET provides tomographic images with spatial and contrast resolution. Because iodine-131 is the mainstay for therapy in thyroid cancer, and because success or failure of therapy depends on the degree of iodine uptake by the tumor cells, I-124-PET imaging will increasingly act as a surrogate for this treatment. This approach may serve as a model for individualized therapeutic interventions for many other malignant and nonmalignant diseases.

The black carbon aerosols are now recognized for their potential impact on climate and the halogenated compounds are thought to be very important in atmospheric chemistry. However, there are very few studies on the interactions between soot aerosols and halogenated compounds. We report the measurement of the uptake of CH3I on soot. The measured uptake coefficient is 0.0103 ± 0.0015 at a total pressure of 2–4 Torr and 298 K. The results suggest that the uptake of CH3I occurs efficiently on soot particles. The present work suggests that heterogeneous loss of CH3I on soot may influence the concentration of CH3I throughout the atmosphere.

Radioiodine therapy is an effective treatment for lung metastasis from thyroid cancer. However, cases of lung metastasis without iodine uptake are often encountered. In such cases, FDG accumulation in lung lesions is often observed. There is a reverse relationship between iodine and FDG accumulation in thyroid cancer lesions, the so-called “flip-flop” phenomenon. The aim of this study was to assess the relationship between patient age and the occurrence of the flip-flop phenomenon. Eighty-six patients who underwent radioiodine therapy for lung metastasis were studied retrospectively (age 17–73 years; median 60 years; males:females 22:64). We compared the clinical data and imaging findings (size and FDG uptake of lung nodules) between patients with (n = 44) and without (n = 42) iodine uptake in lung metastasis. Significantly more young patients showed iodine accumulation in lung metastasis than old patients (p = 0.0025). Lung metastases with larger size or greater FDG uptake showed no iodine uptake more frequently with significant difference (p = 0.015 and

By using a new resorcin[4]arene-based tetracarboxylate, three functional coordination polymers (CPs)--namely, [(CH3)2NH2][Cd2NaL(HCOO)2(HCOOH)(H2O)]·H2O (1), [(CH3)2NH2]2[CdL]·CH3OH·4H2O (2), and [(CH3)2NH2][Zn2Na3L2(H2O)2]·H2O (3)--have been synthesized under solvothermal conditions (H4L = 2,8,14,20-tetra-pentyl-4,10,16,22-tetrakis((4-carboxybenzyl)oxy)-6,12,18,24-tetra-methoxy-resorcin[4]arene and DMF = N,N'-dimethylformamide). The structures of 1-3 have been confirmed by single-crystal X-ray diffraction analyses and further physically characterized. In 1, L and HCOO(-) link Cd(II) and Na(I) ions to yield an unusual three-dimensional (3D) 4-connected heterometallic framework with (4(2)·6(4))(4·8(3)·10·12) topology. In 2, L anions link Cd(II) ions to give a 3D binodal 4-connected framework with (4(2)·6(3)·8)2 topology. In 3, adjacent dodecanuclear heterometallic clusters are joined together by L anions, yielding a two-dimensional (2D) (3,8)-connected (3·4(2))(3(4)·4(6)·5(6)·6(8)·7(3)·8) network. Most strikingly, CPs 1 and 2 display unusual metal-ion exchange characters. CP 2 shows remarkable reversible adsoption of I2 molecules. In addition, CPs 1-3 can selectively adsorb organic dyes and exhibit highly luminescent sensing properties for small molecules.

Dual energy CT (DECT) of the chest is most commonly used to visualize the iodine distribution in the pulmonary parenchyma as a surrogate for pulmonary perfusion. Additionally, pulmonary ventilation can be assessed using inhaled contrast agents. This functional information is obtained along with the high-resolution anatomical information CT provides. Visualization of iodine uptake has also been investigated in thoracic oncologic imaging; here, it may aid in the characterization of pulmonary nodules. Furthermore, DECT offers the possibility for novel reconstruction techniques which can optimize contrast-to-noise ratio in chest CT. Overall, thoracic DECT is still in early stages of development. While numerous studies have demonstrated its feasibility and diagnostic potential, reliable data on the value of the technique for clinical decision-making is still missing. Currently, only lung perfusion assessment and post-processing techniques for image contrast optimization can be considered established enough for clinical use.

According to European recommendations, the external dose rate (ED) in radioiodine-treated goitre patients can be determined by estimating from calculation of the residual activity (RA) in the patient based on radioiodine uptake measurements or by measuring ED directly. In the European guidelines, "Radiation Protection 97", it is assumed that an RA of 600 MBq (131)I causes an ED of 30 microSv/h at a distance of 1 m. This implies a slope of 0.05 microSv/h/MBq for the ratio ED/RA relationship, but, theoretically, this ratio is higher, at 0.07, a difference that is due to measurement in air versus in a scattering medium. We sought to investigate what the true ratio might be.Sixty-six patients scheduled for radioiodine treatment of benign goitre (mean size 102 mL, range 20-440), who received (131)I orally (mean 984 MBq, range 173-3700) were examined. After 24 h and 96 h iodine uptake percentage we examined 7269 patients scheduled for radioiodine treatment of benign goitre (mean size 1042 mL, range 20-440) who received (131)I orally (mean 101,100 MBq, range 180-3700). After 24 h and 96 h, the iodine uptake was determined, RA calculated and ED measured using a hand-held dosimeter.At 24 and 96 h, we observed a slope ratio of 0.103 microSv/h/MBq (95 % CI: 0.09564-0.111) and 0.101 microSv/h/MBq (95 % CI: 0.0915-0.11107), respectively, for the ED/RA relationship. None of the confidence intervals included the value 0.05 microSv/h/MBq, reflecting that the observed slopes differed significantly from the expected slope (p0.001). Consequently, an RA of 600 MBq typically causes an ED of 60 and not 30 microSv/h, and therefore dose rates based on radioiodine uptake measurements and established assumptions were only about half as high as the directly measured values. We noticed that with an RA roughly below 450 MBq, the anticipated slope of 0.05 microSv/h/MBq is within the prediction interval of our claimed ratio, therefore we cannot rebut the anticipated slope for lower doses.Dose-rate estimates based on radioiodine uptake measurements and established assumptions were only about half as high as the directly measured values in patients receiving doses higher than the widely accepted limits for outpatient treatment. This finding may have substantial implications for us, in that it makes a considerable difference whether the radiation precautions are taken to limit doses to the patient's surroundings and for deciding if a patient may or may not be regarded as an outpatient, as well as for the safe discharge of an inpatient from hospital.

Iodine concentration levels in both food and mother’s milk of 13 breast-feeding mothers living in the Euroregion of the Neisse river were determined: the investigations covered periods of time between two and four weeks.On average, the German mothers consumed 166±59 μg iodine per day via food. Larger uptakes were also observed due to additional iodine supplementation in the form of tablets (242-391 μg/d). On the other hand, the Polish mothers had iodine uptakes of only 70±38 μg/d due to low consumptions of dairy, eggs and marine fishes or corresponding products, iodine being supplied to them mainly in the form of salt contained in soups. For milk produced by German mothers, average iodine levels were 81±25 μg/kg, for Polish mothers 65±24 μg/kg. The mothers who were supplemented with iodine showed higher levels of 217±42 and 252±81 μg/kg, respectively.It is obvious from the data that there is no significant relationship between iodine uptake via food and the concentration of iodine in milk. Accordingly, the average transfer factor food/mother’s milk can be regarded only as a preliminary value giving some orientation; this holds to be all the more valid as transferent factors demonstrate large distribution ranges also among different mothers. Nevertheless, average transfer factors were very similar for mothers with and without supplementation (0.58-0.56 d/kg). However, the Polish mothers low in iodine supply displayed higher transfer factors of 1.3 d/kg. But, since this latter value was derived from studies with just two mothers, additional investigations are required to corroborate this value.

To investigate the potential relationship between perfusion parameters from first-pass dual-input perfusion computed tomography (DI-PCT) and iodine uptake levels estimated from dual-energy CT (DE-CT). The pre-experimental part of this study included a dynamic DE-CT protocol in 15 patients to evaluate peak arterial enhancement of lung cancer based on time-attenuation curves, and the scan time of DE-CT was determined. In the prospective part of the study, 28 lung cancer patients underwent whole-volume perfusion CT and single-source DE-CT using 320-row CT. Pulmonary flow (PF, mL/min/100 mL), aortic flow (AF, mL/min/100 mL), and a perfusion index (PI = PF/[PF + AF]) were automatically generated by in-house commercial software using the dual-input maximum slope method for DI-PCT. For the dual-energy CT data, iodine uptake was estimated by the difference (λ) and the slope (λHU). λ was defined as the difference of CT values between 40 and 70 KeV monochromatic images in lung lesions. λHU was calculated by the following equation: λHU = |λ/(70 − 40)|. The DI-PCT and DE-CT parameters were analyzed by Pearson/Spearman correlation analysis, respectively. All subjects were pathologically proved as lung cancer patients (including 16 squamous cell carcinoma, 8 adenocarcinoma, and 4 small cell lung cancer) by surgery or CT-guided biopsy. Interobserver reproducibility in DI-PCT (PF, AF, PI) and DE-CT (λ, λHU) were relatively good to excellent (intraclass correlation coefficient [ICC]Inter = 0.8726–0.9255, ICCInter = 0.8179–0.8842; ICCInter = 0.8881–0.9177, ICCInter = 0.9820–0.9970, ICCInter = 0.9780–0.9971, respectively). Correlation coefficient between λ and AF, and PF were as follows: 0.589 (P

There are reports on physiologic and pathologic mediastinal uptake on radioiodine imaging in patients with thyroid carcinoma. The most commonly reported physiologic causes of mediastinal uptake are esophageal retention of salivary secretion and uptake by hyperplastic or normal thymus gland. In this study, we evaluated physiologic cardiac blood pool (CBP) activity and its associated findings on radioiodine imaging. Cardiac blood pool activity was evaluated in 186 postablation and 32 posttherapy scans. After oral radioiodine administration, imaging was initiated on day 7. Thyroglobulin, anti-thyroglobulin and TSH blood level determination was carried out in all patients. Whole-body scans were inspected with regard to residual thyroid uptake, esophageal uptake, CBP activity, hepatic activity and metastatic iodine uptake. Uptake in the residual thyroid tissue was graded visually as mild (m), moderate (M) and significant (S). Whenever CBP activity was detected on visual inspection, its intensity was graded as mild (1), moderate (2), and significant (3). Cardiac blood pool activity was detected in 61 postablation scans (33 %). Residual thyroid uptake was observed in all patients with CBP. A significant correlation existed between the intensity of uptake and the presence of CBP (p

Contrast-enhanced digital breast tomosynthesis (CE-DBT) uses an iodinated contrast agent to image the threedimensional breast vasculature. The University of Pennsylvania is conducting a CE-DBT clinical study in patients with known breast cancers. The breast is compressed continuously and imaged at four time points (1 pre-contrast; 3 postcontrast). A hybrid subtraction scheme is proposed. First, dual-energy (DE) images are obtained by a weighted logarithmic subtraction of the high-energy and low-energy image pairs. Then, post-contrast DE images are subtracted from the pre-contrast DE image. This hybrid temporal subtraction of DE images is performed to analyze iodine uptake, but suffers from motion artifacts. Employing image registration further helps to correct for motion, enhancing the evaluation of vascular kinetics. Registration using ANTS (Advanced Normalization Tools) is performed in an iterative manner. Mutual information optimization first corrects large-scale motions. Normalized cross-correlation optimization then iteratively corrects fine-scale misalignment. Two methods have been evaluated: a 2D method using a slice-by-slice approach, and a 3D method using a volumetric approach to account for out-of-plane breast motion. Our results demonstrate that iterative registration qualitatively improves with each iteration (five iterations total). Motion artifacts near the edge of the breast are corrected effectively and structures within the breast (e.g. blood vessels, surgical clip) are better visualized. Statistical and clinical evaluations of registration accuracy in the CE-DBT images are ongoing.

Single-step iodination is often performed in preference to use of a radiometal label for initial animal biodistributions. Yet loss of iodine occurs in vivo so that it is important to measure uptake (%ID/g) differences between radiolabels.Murine biodistributions of four radioiodinated and (111)In-labeled cognate anti-carcinoembryonic antigen antibodies were compared. Uptakes were obtained in athymic mice out to 96 hours for diabody, minibody, scFv-Fc, and intact humanized (M5A) versions of the T84.66 antibody. Tissues included liver, spleen, kidneys, lungs, and human LS174T colorectal xenografts. Ratios (R) of iodine uptake to indium uptake were calculated.For all cognates, no significant differences were found in the blood uptakes between the two labels. In normal solid organs, iodine was generally cleared more rapidly with decreasing molecular weight (MW). In liver and spleen by 24 hours, the R value was 5% for diabody and minibody, whereas a value of 50% was seen for the intact mAb. Renal differences were even more marked for the two lower MW species. Tumor losses, however, were found to be essentially independent of MW and were modest; 50% by 48 hours. To test the generality of the results, comparisons were then made for normal organs and tumors of the R values found above for M5A and MN-14 intact antibody literature results. Good agreement, within estimated errors in R, was seen between these two cases, although (111)In and (88)Y were the respective radiometals.Loss of iodine from labeled antibodies can be marked in normal organs and that correction (by 1/R) of the iodine biodistribution to estimate the associated radiometal result may be possible. Explicit differences between the two types of biodistribution also imply that separate uptake results need to be considered when evaluating the impact on imaging and therapy using various possible radiolabels.

The objective of our study was to assess the accuracy of iodine-related attenuation and iodine quantification as imaging biomarkers of iodine uptake in renal lesions on a single-phase nephrographic image with dual-energy MDCT.Fifty-nine patients (41 men, 18 women; age range, 28-84 years) with 80 renal lesions underwent contrast-enhanced dual-energy CT during the nephrographic phase of enhancement. Renal lesions were characterized as enhancing or nonenhancing on color-coded iodine overlay maps using iodine-related attenuation (in Hounsfield units) and iodine quantification (in milligrams per milliliter). For iodine-related attenuation the iodine uptake thresholds of 15 and 20 HU were tested; a threshold of 0.5 mg/mL was used for iodine quantification. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of iodine-related attenuation and iodine quantification were calculated from chi-square tests of contingency with histopathology or imaging follow-up as the reference standard. The 95% CIs were calculated from binomial expression. Differences in sensitivity and specificity were assessed by means of McNemar analysis.A significant difference in sensitivity and specificity was found between iodine-related attenuation with the thresholds of 15 HU (sensitivity, 91.4%; specificity, 93.3%; PPV, 91.4%; NPV, 93.3%) and 20 HU (sensitivity, 77.1%; specificity, 100%; PPV, 100%; NPV, 84.9%) (p = 0.008) and between iodine quantification (sensitivity, 100%; specificity, 97.7%; PPV, 97.2%; NPV, 100%) and iodine-related attenuation with a threshold of 20 HU (p = 0.004). No significant difference in sensitivity and specificity was found between iodine quantification and iodine-related attenuation with a threshold of 15 HU.Contrast-enhanced dual-energy MDCT with iodine-related attenuation and iodine quantification allows accurate evaluation of iodine uptake in renal lesions on a single-phase nephrographic image.

Iodine supply is important to avoid neonatal hypothyroidism. This study evaluated whether protein restriction during lactation affects iodine transfer to the pups through the milk. We studied lactating rats fed an 8% protein-restricted diet (PR), a control 23% protein diet (C), and an energy-restricted diet group (ER). On days 4, 12 and 21, mothers were separated from their pups for 4 h, injected with 131 I IP, and put together with their pups. The animals were killed 2 h later. PR pups had a significant decrease in iodine uptake in the gastric content and duodenal mucosa on the 4th day. On the contrary, at 12 and 21 days radioiodine was increased in the gastric content and in the duodenal mucosa. ER pups had an increase in iodine uptake in the gastric content and in the duodenal mucosa only at the end of lactation. The thyroid iodine uptake in PR pups was significantly decreased on the 4th day and significantly increased on the 21st day compared to control. When injected IP with an equivalent amount of 131 I, the PR pups had a decrease in thyroid iodine uptake on the 4th and 12th day, while ER pups had no significant changes. So, these data suggest that protein restriction during lactation was associated with lower iodine secretion into the milk in the beginning of lactation. However, at the end of lactation, an adaptation process seems to occur leading to a higher transfer of iodine through the milk that compensates the impairment of thyroid iodine uptake in these pups.

OBJETIVO: O atordoamento do tecido tireoidiano após doses diagnósticas de iodo-131 é descrito como causa de baixa captação e resposta insatisfatória a doses terapêuticas subseqüentes. O objetivo do presente trabalho foi desenvolver um modelo experimental do atordoamento tireoidiano pós-actínico. MATERIAIS E MÉTODOS: Um total de 63 camundongos recebeu dose equivalente de 45 Sv na tireóide, mediante irradiação com iodo-123. Esta dose é similar à estimada para os remanescentes tireoidianos após administração de 185 MBq (5 mCi) de iodo-131 para pesquisa de corpo inteiro. As medidas de captação tireoidiana de uma dose traçadora de iodo-131 foram efetuadas em subgrupos de nove animais, 2, 3, 5, 7, 12 e 26 dias após a irradiação. A captação nestes subgrupos foi correlacionada à de um grupo controle de nove animais não irradiados. RESULTADOS: A captação de iodo no grupo controle foi de 9,26%. Não foi observada variação significativa do valor médio de captação no período de tempo estudado. Houve aumento da variância das medidas efetuadas cinco dias após a irradiação, quando quatro dos nove animais apresentaram captação menor que 60% da média do grupo controle. CONCLUSÃO: Não houve queda sistemática da captação nos animais submetidos à dose de 45 Sv, notando-se, entretanto, tendência a maior flutuação na captação cinco dias após a irradiação. Estes achados podem ser decorrentes de diferenças interespécies ou podem indicar que o atordoamento com doses nesta faixa dependa de características individuais ou anormalidades funcionais prévias, que se somam ao efeito da radiação.

Summary Aim: The influence of physiological and pharmacological amounts of iodine on the uptake of radioiodine in the thyroid was examined in a 4-compartment model. This model allows equations to be derived describing the distribution of tracer iodine as a function of time. The aim of the study was to compare the predictions of the model with experimental data. Methods: Five euthyroid persons received stable iodine (200 μg, 10 mg). 1-123-uptake into the thyroid was measured with the Nal (Tl)-detector of a body counter under physiological conditions and after application of each dose of additional iodine. Actual measurements and predicted values were compared, taking into account the individual iodine supply as estimated from the thyroid uptake under physiological conditions and data from the literature. Results: Thyroid iodine uptake decreased from 80% under physiological conditions to 50% in individuals with very low iodine supply (15 μg/d) (n = 2). The uptake calculated from the model was 36%. Iodine uptake into the thyroid did not decrease in individuals with typical iodine supply, i.e. for Cologne 65-85 μg/d (n = 3). After application of 10 mg of stable iodine, uptake into the thyroid decreased in all individuals to about 5%, in accordance with the model calculations. Conclusion: Comparison of theoretical predictions with the measured values demonstrated that the model tested is well suited for describing the time course of iodine distribution and uptake within the body. It can now be used to study aspects of iodine metabolism relevant to the pharmacological administration of iodine which cannot be investigated experimentally in humans for ethical and technical reasons.

The colposcopist must distinguish between two patterns: nonsuspicious findings and suspicious findings. With experience, the colposcopist will succeed more and more in distinguishing between the two, thereby markedly reducing the number of biopsies. Suspicious findings are not synonymous with abnormal findings because the latter are not always due to premalignant lesions. A number of features are of value in the different diagnosis of colposcopic findings: sharp borders, response to acetic acid (white epithelium), surface contour, appearance of blood vessels, surface extent (size), combinations of abnormalities, iodine uptake, and keratinization. The diagnostic features described above can be expressed to varying degrees, and can be found singly or in combination. The more distinct a feature is and the greater the variety of features seen in combination, the higher the index of suspicion. Attempting to differentiate between the various grades of CIN (SIL) colposcopically is more questionable, as these lesions are regarded now as forming a spectrum of the same biologic process.

Thyroid dose estimates for European populations following the Chernobyl accident in 1986 have been presented in the literature. These dose estimates used standard values for parameters such as thyroid mass, iodine uptake and biological half-life. Previous work has shown that these values are not representative of European populations and that local values should be utilized. Using published data on revised thyroid dose estimates, thyroid dosimetry data arising as a result of the Chernobyl accident are presented for 22 European countries. When these are compared with previously published estimates it is found that in all cases the previous results underestimate the thyroid dose by up to a factor of 4. Risk estimates on the incidence of fatal and non-fatal thyroid cancers are also determined from this new data and, again, the results are underestimated. The results show an increase in the number of fatal cancers, rising from 149 as predicted by the NEA to 310 under the new estimates, and from 180 as predicted by UNSCEAR to the new estimate of 380.

A commercial impregnating coal-tar pitch was thermally treated at 430°C for times varying between 2 and 6 h and the same pitch was air-blown at 275°C for between 10 and 30 h. Both series of pitches were characterized and their properties compared. The pitches from the thermal treatments contained mesophase, the amount increasing from 10 vol.% to 65 vol.% with increasing time of treatment, whereas those from the air-blowing were completely isotropic. The study of the pitches revealed that the thermally treated pitches still contained a considerable amount of light compounds together with the large planar molecules generated. On the contrary, light components polymerized to a considerable extent during air-blowing to form cross-linked molecules. Evidence of cross-linked structures is provided by a decrease in the iodine uptake and also by the X-ray diffraction results. Furthermore, extensive removal of aliphatic hydrogen took place during pitch air-blowing, as confirmed by the increase in the aromaticity indices of the pitches.

The influence of lead acetate (50 mg per kg body weight) on the 131iodine (131I) biokinetics (uptake and retention) in rat thyroid and serum levels of triiodothyronine (T3) as well as thyroxine (T4) was evaluated as a function of time and in combination with lithium treatment. The 2-h and 24-h uptake of 131I in the thyroid was stimulated significantly by lead treatment. The 24-h uptake showed a maximum stimulation after 4 months of lead treatment. Lithium supplementation, however, showed the opposite effect by reducing the iodine uptake, whereby the maximum decrease was noticed after 2 months of treatment. Further, simultaneous lead and lithium treatment resulted in an even more pronounced increase of 2-h 131I uptake with a maximum after 3 months. However, the 24-h uptake after 3 months and 4 months of treatment did not differ significantly from the lead treated reference groups. The thyroidal biological half-life of 131I (Tbiol) was found to have clearly increased following the lead/lithium treatment. Interestingly, the combined lead/lithium treatment applied for 4 months caused a further growth of Tbiol, thus reflecting an increased retention of 131I. A maximum increase of Tbiol was seen after 2 months of combined treatment. A progressive decline of the circulating T3 and T4 levels following lead or lithium treatment was noticed and was more pronounced after combined treatment.

In this investigation, we applied quantitative CT methods to characterize contrast enhanced lymph nodes opacified using iodinated contrast media for indirect CT lymphography. Iodinated nanoparticles were injected into the buccal submucosa and SQ into the metatarsus and metacarpus of four normal swine (1.0-4.0 ml/site, 76 mg I/ml). Attenuation (HU), volume (cm3), iodine concentration (mg I/cm3), total iodine uptake (mg I), contrast-to-noise ratio (CNR), and percent injected dose (%ID) were estimated in opacified inguinal, cervical and parotid/mandibular lymph nodes using manual image segmentation techniques on 24 hour post-contrast CT images. Lymph node volumes estimated by multiple slice ROI analysis were compared with estimates obtained by post-excisional weight measurements. HU and iodine concentration increased 5-20 fold in opacified nodes (p < 0.01) and CNR increased more than four-fold (p < 0.001). %ID ranged between 3.5 and 11.9% and did not appear dose related. ROI estimated lymph node volumes approximated volumes calculated from weight measurements. (R2 = 0.94, p < 0.0001). We conclude that interstitially injected iodinated nanoparticles increase attenuation and conspicuity of targeted nodes on CT images. Quantitative methods could play an important clinical role in more accurate metastasis detection.

Human exposure to perchlorate is commonplace because it is a contaminant of drinking water, certain foods, and breast milk. The U.S. Environmental Protection Agency (EPA) conducted a perchlorate risk assessment in 2002 that yielded a reference dose (RfD) based on both the animal and human toxicology data. This assessment has been superceded by a recent National Academy of Science (NAS) review that derived a perchlorate RfD that is 20-fold greater (less stringent) than that derived by the U.S. EPA in 2002. The NAS-derived RfD was put on the U.S. EPA's Integrated Risk Information System (IRIS) database very quickly and with no further public review. In this commentary we raise concerns about the NAS approach to RfD development in three areas of toxicity assessment: the dose that the NAS described as a no observable adverse-effect level is actually associated with perchlorate-induced effects; consideration of uncertainties was insufficient; and the NAS considered the inhibition of iodine uptake to be a nonadverse effect. We conclude that risk assessors should carefully evaluate whether the IRIS RfD is the most appropriate value for assessing perchlorate risk.

A 16-year-old adolescent girl post total thyroidectomy for papillary thyroid carcinoma presented for postsurgical radioablative therapy. A whole-body I scintigraphy revealed not only expected activity in the thyroid bed but also asymmetric tracer distribution in the mandible and 2 foci of increased I accumulation in the distal left lower extremity. SPECT/CT images localized the activity to the donor sites of an autologous left fibular bone graft, harvested 8 years earlier to repair her mandible. Our case demonstrates that iodine accumulation can occur at the site of bone surgery many years after intervention and should be differentiated from iodine-avid metastases.

to measure the radio active iodine uptake in different variants ofgoiter                                                                                             MATERIALS & METHODS subjects were divided into two group’s one group with normal levels of T 3, T 4 & TSH and no goiter which is control group and the other one is examination group which is divided in to three sub groups eu-thyroid goiter, hypo-thyroid goiter and hyper-thyroid goitre cases. Each group ishaving 10 subjects. All the subjects are females aged 35 yrs±5 and no one is receiving any drugs since 6 weeks just before the beginning of the study.Radio active iodine uptake is measured by using kits. Radio active iodine uptake is measured at 2,24 and 48 hrs. RESULTS AND OBSERVATIONS At 2 hrs:in hypo-thyroid cases RAIU is elevated,in hyper-thyroid subjects RAIU uptake is increased and in eu-thyroid subjects the uptake is decreased. At 24 hrs:in hypo-thyroid cases RAIU is decreased, in hyper-thyroid subjects RAIU uptake is increased and in eu-thyroid subjects the uptake is decreased.At 48 hrs:RAIU uptake is reduced in hypo-thyroid individuals, in hyper-thyroid subjects the uptake is increased and in eu-thyroid subjects the uptake is decreased CONCLUSION The Radio active iodine uptake is reduced at 2 hrs, 24 hrs and 48 hrs in eu-thyroid subjects.Radio active iodine uptake is increased at 2 hrs and decreased at 24 hrs and 48 hrs in hypo-thyroid subjects Radio active iodine uptake is reduced at 2 hrs, 24 hrs and 48 hrs in hyper-thyroid subjects.

Iodine is an essential microelement for humans and iodine deficiency disorder (IDD) is one of the most widespread nutrient-deficiency diseases in the world. Iodine biofortification of plants provides an attractive opportunity to increase iodine intake in humans and to prevent and control IDD. This study was conducted to investigate the iodine uptake and accumulation in edible portion of two fruit trees: plum and nectarine, and two horticultural crops: tomato and potato. Two type of iodine treatments (soil and foliar spray application), and, for fresh market tomato, two production systems (open field and greenhouse hydroponic culture) were tested. The distribution of iodine in potato stem and leaves, and in plum tree fruits, leaves, and branches was investigated. Iodine content of potato tubers after postharvest storage and processing (cooking), and iodine content of nectarine fruits after postharvest storage and processing (peeling) were also determined. Differences in iodine accumulation were observed among the four crops, between applications, and between production systems. In open field, the maximum iodine content ranged from 9.5 and 14.3 μg 100 g−1 for plum and nectarine fruit, to 89.4 and 144.0 μg 100 g−1 for potato tuber and tomato fruit, respectively. These results showed that nectarine and plum tree accumulated significantly lower amounts of iodine in their edible tissues, in comparison with potato and tomato. The experiments also indicated hydroponic culture as the most efficient system for iodine uptake in tomato, since its fresh fruits accumulated up to 2423 μg 100 g−1 of iodine. Iodine was stored mainly in the leaves, in all species investigated. Only a small portion of iodine was moved to plum tree branches and fruits, and to potato stems and tubers. No differences in iodine content after fruit peeling was observed. A significant increase in iodine content of potato was observed after baking, whereas a significant decrease was observed after boiling. We concluded that iodine biofortified fresh market tomato salad, both from field and hydroponics cultivation, and baked potatoes can be considered as potential functional foods for IDD prevention.

Globally, deficiency of iodine and the often concomitant deficiency of selenium are major causes of hypothyroidism in adults. In this wider perspective, the main focus is on the effects of iodine deficiency during pregnancy, both for the mother and child. Iodine deficiency and the significance of certain foodstuffs which affect iodine uptake, goitrogens, are discussed separately (see Chaps. 6 and 33).

Field experiments were performed to determine the washout coefficient of iodine vapour scavenged by rain. They consisted in emitting a known amount of stable iodine and sampling the wet deposit in collectors conveniently placed to eva­ luate the fraction of plume scavenged by rain. It was shown that precautions are to be taken to avoid a superposition of direct deposition of iodine vapour by reaction on collector surfaces (dry deposition) and indirect deposition by rain scavenging (wet deposition). The data obtained (mean value = 8.2 x 10 -5 s -1 vali­ date the theorical values currently used and indicate that, under the conditions of these experiments, iodine uptake by rain droplets is apparently irreversible.

A highly stable pillared and double-walled zinc(II) metal-organic framework with regular nanochannels displays single-crystal to single-crystal transformation upon desolvation and a large quantity of iodine uptake, controlled release, and electrical conductivity elevation due to synergy between the iodine guests and the host framework.

This chapter reviews the XRF technique, with emphasis on the physical background and clinical applications. Necessary equipment, together with the methodological limitations and benefits, is discussed and a brief guide before starting XRF measurements is also provided. Iodine uptake and excretion can be assessed by 131 I measurements or urinary iodine, whereas information on the amount of iodine stored in the thyroid, in the iodine pool, is not as commonly obtained. The iodine pool can be estimated by noninvasive X-ray fluorescence (XRF) analysis. Depending on the choice of equipment, the iodine estimation can be made quantitatively or by imaging the iodine distribution. The technique involves a radioactive source or an X-ray tube for irradiation of the stable iodine in the thyroid, together with a detector that registers the subsequent emission of characteristic X-ray photons. The method is noninvasive and can be used in vitro as well as in vivo . The equipment consists of a radiation source, a detector, electronics, and a spectroscopy program. The radiation dose involved in a measurement is very low. The areas of special interest are monitoring of iodination programs, identification of individuals with a small iodine pool who are at special risk of developing hypothyroidism in iodine deficiency, and also investigations of mechanisms of thyroid disease in iodine overload.

Inhalation is a prominent pathway for radiation dose contributions from environmental or occupational intakes of radioactive iodine. Radioactive iodine releases to the environment that affect the general public and deliver radiation dose are of particular concern. Inhalation intakes of iodine are possible from workplace exposures or releases to the environment, and potential health risks are an outcome. Extrathoracic and bronchial depositions follow a normal distribution. Bronchiolar and alveolar deposition are best fit by a lognormal distribution. Breathing rate, trachea diameter and particle mass density have the greatest influence on particulate deposition for 1 μm AMAD particles. In the United States, ICRP 30 is the lung model of regulatory concern and, therefore, the more commonly employed. The International Commission on Radiological Protection developed and issued the “New Lung Model” (ICRP, 66) in 1994. ICRP 66 incorporates recent knowledge and research into lung deposition, retention and clearance. Inhalation models are necessary for estimates of iodine uptake and deposition that may result in radiation exposure among workers or members of the public. The estimates of radiation dose via internal modeling have significant uncertainty, due to the variability in parameters involved in model calculations. The uncertainty in internal dosimetry can be a considerable component of the overall uncertainty in radiation dose assessment. The parameters used for dose assessment have inherent variability, which results in uncertainty for output variables that may be characterized by various known distributions.

The influence of chemical forms of iodine (I− and I2) on the uptake by wheat plant (Triticum aestivum) as a function of growth, in terms of days since germination, has been studied. The normalized amount on fresh weight basis of I− and I2 absorbed by root, shoot and plant as a whole was determined by independent experiments. Both chemical forms of iodine were tagged with131I for radiometric assay. The transport index, depletion factor and shoot to root ratios were determined. The total amount of iodine absorbed increases as a function of growth in case of both chemical forms; however, uptake and transportation of I− is greater as compared to I2.

Advanced thyroid malignancy can occur early in the course of the disease, or as late as 20 to 25 years after the initial diagnosis. The basic treatment is total thyroidectomy with central node dissection regardless of the histologic type. The nonresectable disease is treated with 131I if the tumor has iodine uptake. Further ablative surgery for resectable disease is governed by location and histologic cell type. Otherwise external radiation and chemotherapy (Adria-mycin) is used. Anaplastic, primary squamous cell and pure papillary and some predominantly papillary carcinomas and some Hurthle cell carcinomas do not have 131I uptake and fall into this latter category. The surgeon must be aware of this problem in the noniodine uptake tumors and take special care to remove all surgically resectable disease.

The removal of gaseous iodine from air by water sprays is measured, using both ordinary water and a solution buffered to a pH near 9.5 with a carbonate mixture. The results are compared to the theo...

Background: Radiolabeled iodine uptake is a useful tool in the study of thyroid diseases. Aim: To obtain normal values for 131 Iodine thyroid uptake in healthy volunteers. Material and methods: A total of 105 subjects were included (52 males and 53 females), with a mean age of 45 years (range: 20 to 68, evenly distributed in decades). A questionnaire was applied and a clinical examination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral 131I dose was 5-10 fiCi, and a Thyrad equipment was used for measurements at 2 and 24 h. Results: Mean global iodine uptake was 5.5%±1.8% (range: 2.3-12.0) at 2 h and 16.2±4.8% (range: 6.5-30.1) at 24 h. The values at 2 h among women and men were 6.0±1.8 and 4.9±1.6%, respectively, (p

Iodine-enhanced vegetable has been proven to be an effective way to reduce iodine deficiency disorders in many regions. However, the knowledge about what mechanisms control plant uptake of iodine and where iodine is stored in plants is still very limited. A series of controlled experiments, including solution culture, pot planting, and field experiments were carried out to investigate the uptake mechanism of iodine in different forms. A new methodology for observing the iodine distribution within the plant tissues, based on AgI precipitation reaction and transmission electron microscope techniques, has been developed and successfully applied to Chinese cabbage. Results show that iodine uptake by Chinese cabbage was more effective when iodine was in the form of IO(3) (-) than in the form of I(-) if the concentration was low (

Aim: To study the geographical distribution of high thyroid-stimulating hormone (TSH) level in the Marche region (central Italy). Methods: Data were drawn from the Register of Neonatal Screening for Congenital Hypothyroidism (CH) of the Marche region (Italy), located at the Child Neuropsychiatry Department of Civil Hospital in Fano (Marche, Italy). Data were analyzed by Ohno's method. Results: The findings of this study show a nonuniform distribution of high TSH levels in the Marche region, with an evident gradient from North to South. Conclusions: It is not possible to provide a definitive interpretation of these findings, although the specialized literature suggests that a high level of TSH in neonates should be interpreted as a marker of insufficient iodine uptake. Other factors affecting TSH level are also taken into consideration.

OBJETIVO: Diferentes métodos são usados para determinar atividade do radioiodo para tratamento de hipertireoidismo (doença de Graves). Alguns não consideram a dose absorvida pela tireóide ou os parâmetros necessários para este cálculo. A relação entre dose absorvida e atividade administrada depende da meia-vida efetiva, da captação do iodo e da massa da tireóide de cada paciente. O objetivo deste trabalho é propor uma metodologia para tratamento individualizado com 131I em pacientes portadores de hipertireoidismo da doença de Graves. MATERIAIS E MÉTODOS: Usou-se um simulador de tireóide-pescoço desenvolvido no Instituto de Radioproteção e Dosimetria contendo solução de 131I, para calibração da gama-câmara e sonda cintilométrica do Serviço de Medicina Nuclear do Hospital Universitário Clementino Fraga Filho da Universidade Federal do Rio de Janeiro. RESULTADOS: O campo de visão colimador-detector apresentou valores compatíveis com o tamanho da glândula para as distâncias de 25 cm (sonda de captação) e 45,8 cm (gama-câmara). Os fatores de calibração (cpm/kBq) foram 39,3 ± 0,78 e 4,3 ± 0,17, respectivamente. O intervalo entre 14 e 30 horas da curva de retenção permite o cálculo de atividade entre dois pontos, para determinação da meia-vida efetiva do iodo na tireóide. CONCLUSÃO: A utilização de equipamentos usualmente disponíveis em serviços de medicina nuclear é viável, tornando esta metodologia simples, eficaz e de baixo custo. OBJECTIVE: Several methods are utilized for determining the radioiodine activity in the treatment of Graves' disease (hyperthyroidism). Some of this methods do not take into consideration the thyroid absorbed dose or the necessary parameters for this estimation. The association between absorbed dose and administered activity depends on effective half-life, iodine uptake and thyroid mass of each patient. The present study was aimed at developing a methodology for individualized 131I therapy for Graves' disease in patients with hyperthyroidism of the Graves' disease. MATERIALS AND METHODS: A neck-thyroid phantom developed at Instituto de Radioproteção e Dosimetria, containing a standard solution of 131I, was utilized for calibrating the scintillation gamma camera and uptake probe installed in the Department of Nuclear Medicine of the Hospital Universitário Clementino Fraga Filho da Universidade Federal do Rio de Janeiro. RESULTS: The view angle of the collimator/detector assembly presented values compatible with the thyroid gland size for distances of 25 cm (uptake probe) and 45.8 cm (scintillation gamma camera). Calibration factors were 39.3 ± 0.78 and 4.3 ± 0.17 cpm/kBq, respectively. The 14-30-hour interval in the retention curve allows the estimation of activity between two points for determining the effective iodine half-life in the thyroid. CONCLUSION: The utilization of equipment usually available in nuclear medicine clinics is feasible, so this is a simple, effective and low cost methodology.

There are currently many unanswered questions surrounding the prevalence of perchlorate in the environment, the possible exposures and effects, and the risk management strategies available to manage perchlorate contamination. Further information must be obtained in each of these areas in order to develop successful and appropriate strategies for handing perchlorate contamination now and in the future. Because of the uncertainty involved in evaluating toxicological data, the states and federal agencies using this information may use and interpret it somewhat differently to promulgate different standards and advisory levels. It is important to note that the status of the knowledge of perchlorate exposure and risks continues to evolve and it will be essential to periodically re-evaluate what is known about this chemical. However, the reference dose recommended by National Research Council and adopted by the U.S. Environmental Protection Agency will protect the health of even the most sensitive groups of people over a lifetime of exposure.