A disfunção tireoidiana durante a gestação cursa com maior morbidade materno-fetal. A deficiência de iodo continua sendo uma causa importante de disfunção tireoidiana. O estado de São Paulo é considerado uma região suficiente em iodo. No entanto, as gestantes são consideradas grupo de risco para deficiência iódica devido a maior necessidade de produção dos hormônios tireoidianos ao longo da gestação. Este trabalho objetiva avaliar a suficiência iódica de gestantes residentes em São Paulo e correlacionar as concentrações de iodo com os valores dos hormônios tireoidianos em cada trimestre de gestação. Métodos: Foi realizado estudo transversal com gestantes em pré-natal de baixo risco nos três trimestres de gestação. Foram analisadas 251 mulheres sem doença tireoidiana prévia ou atual, com autoanticorpos antitireoidianos negativos e que não estavam em uso de polivitamínico contendo iodo. A concentração de iodo urinário foi feita em amostra isolada pelo método Sandell- Kolthoff. As dosagens de TSH, T4, T3, T4 livre (T4L), T3 livre (T3L), tireoglobulina (TG), globulina ligadora da tiroxina (TBG) anticorpo antitireoperoxidase (AntiTPO), antitireoglobulina (AntiTG), estradiol e hCG foram feitas por método eletroquimioluminescente. Ultrassonografia da tireoide foi realizada com aparelho Philips IU-22 e transdutor 7,5-12 mHz. Resultados: Os valores de TSH correspondentes aos percentis 2,5 e 97,5 foram 0,38 uIU/mL e 4,23 uIU/mL, respectivamente. Observou-se valores de TSH > 2,5-3,0 uIU/mL em 13,1% gestantes. Valores de TSH > 4 uIU/mL foi observado em 3,6% dos casos. Os valores de T4T e T3T correspondentes aos percentis 2,5 e 97,5 foram 7,8 ug/dL e 16,1 ?g/dL; 122 ng/dL e 249 ng/dL, respectivamente. Os valores de T4l e T3l correspondentes aos percentis 2,5 e 97,5 foram 0,76 ng/dL e 1,42 ng/dL; 0,21 ng/dL e 0,36 ng/dL, respectivamente. Houve aumento significativo na relação T3:T4 ao longo dos trimestres e, em 8% das amostras, essa relação estava acima do valor de referência para gestantes. As dosagens de iodúria não apresentaram diferenças estatísticas entre os três trimestres da gestação. As medianas foram 135ug/L, 153ug/L e 140ug/L, respectivamente. Encontramos iodúria < 150ug/L em 52,2% das gestantes. Comparando o grupo com iodúria < 150ug/L (deficiente em iodo) e o grupo com iodúria entre 150-250ug/L (suficiente em iodo), observou-se diferença significativa nos valores de TSH e de T3 nas gestantes do 2o Trimestre (média de TSH = 2,24 uIU/mL e TSH = 1,78 uIU/mL e média de T3 = 196 ng/dL e T3 = 181 ng/dL entre o grupo deficiente e suficiente, respectivamente). Não houve diferenças significativas entre os valores de TG e o volume tireoidiano ao longo dos trimestres. Conclusão: A frequência de hipotireoidismo subclínico variou de 3,6% a 13,1%, dependendo dos critérios adotados. Não foi possível estabelecer a frequência de hipotiroxinemia materna, devido à ausência de valores de corte de T4l estabelecido na nossa população. Foi encontrada deficiência iódica em 52,2% das gestantes avaliadas. Embora estas gestantes apresentem deficiência leve de iodo, foram necessários mecanismos adaptativos para equilibrar a função tireoidiana materna com possível produção preferencial de T3, aumento da relação T3:T4 e valores mais elevados de TSH. Conclui-se que, embora esta seja uma região suficiente em iodo, as mulheres poderiam se beneficiar com a suplementação deste nutriente durante a gestação / Thyroid dysfunction in pregnancy is associated with increased rate of obstetrical and neonatal adverse outcomes. Iodine deficiency continues to be a major cause of thyroid dysfunction. The state of São Paulo is considered a sufficient iodine region. However, pregnant women are considered a risk group for iodine deficiency due to an increased demand for production of thyroid hormones throughout pregnancy. This study aims to evaluate the iodine sufficiency of pregnant women in São Paulo and to correlate iodine concentrations with thyroid parameters in each trimester of gestation. Methods: A cross-sectional study was carried out with low-risk pregnant women in the three trimesters of gestation. We analyzed 251 women without history of thyroid disease, with negative antithyroid autoantibodies (anti TPO and anti TG) and who were not taking iodine supplementation. The urinary iodine concentration (UIC) was measured by the Sandell-Kolthoff digestion method in casual morning urine samples. Serum TSH, T4, T3, free T4 (FT4), free T3 (FT3), thyroglobulin (TG), TBG, anti-TPO, anti-TG, estradiol and hCG were measured by the electrochemiluminescence method. Thyroid ultrasound was performed with Philips IU-22 and 7.5-12 mHz transducer. RESULTS: The TSH values corresponding to the 2.5 and 97.5 percentiles were 0.38 IU/mL and 4.23 IU/mL, respectively. TSH levels > 2.5-3.0 IU/mL were observed in 13.1% pregnant women. TSH values > 4 IU/mL were observed in 3.6% of the cases. The T4T and T3T values corresponding to the 2.5 and 97.5 percentiles were 7.8 ug/dL and 16.1 ug/dL; 122 ng/dL and 249 ng/dL, respectively. The FT4 and FT3 values corresponding to the 2.5 and 97.5 percentiles were 0.76 ng/dL and 1.42 ng/dL; 0.21 ng/dL and 0.36 ng/dL, respectively. There was a significant increase in the T3:T4 ratio over the trimesters and in 8% of the samples it was above the reference value for pregnant women. The dosages of UIC did not present statistical differences between the three trimesters of gestation. The medians were 135 ug/L, 153 ug/L and 140 ug/L, respectively. We found UIC < 150 ?g/L in 52.2% of pregnant women. Comparing the group with UIC < 150 ?g/L (iodine deficient) and the group with UIC between 150-250 ug/L (sufficient in iodine), a significant difference was observed in TSH and T3 values in the 2nd trimester (TSH = 2.24 IU/mL and TSH = 1.78 IU/mL and mean T3 = 196 ng/dL and T3 = 181 ng/dL between the deficient and sufficient groups, respectively). There were no significant differences between TG values and thyroid volume over the trimesters. Conclusion: The subclinical hypothyroidism frequency ranged from 3.6% to 13.1%, depending on the adopted criteria. It was not possible to establish frequency of maternal hypothyroxinemia, due to the absence of FT4 cutoff established in our population. Iodine deficiency was found in 52.2% of pregnant women evaluated. Although these pregnant women presented mild iodine deficiency, adaptive mechanisms were necessary to balance thyroid function with possible preferential production of T3, increase in T3:T4 ratio and higher values of TSH. It is concluded that although this is an iodine sufficient region, women could benefit from supplementation of this nutrient during pregnancy

Thesis (PhD)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: A study was undertaken to investigate the radiochemical stability of the βiodoethoxyl moiety, a relatively novel prosthetic group employed in radiopharmaceutical chemistry, in which an oxygen atom in a β-position relative to the radioiodine atom has a stabilising effect on the aliphatic carbon-iodine bond. The investigation was started as a pilot study by synthesising various model compounds containing a β-radioiodoethoxyl moiety, as well as two reference compounds lacking such a moiety. The purpose was to determine the influence of various groups in the vicinity of the β-oxygen atom on the stability of the abovementioned moiety. Radiochemical stability tests were carried out in vitro at 37°C in human blood serum. The results confirmed the superior stability of such a moiety compared to that of the reference compounds and also showed that the branching of such an aliphatic unit resulted in a considerable improvement in its stability, especially over a longer period. The investigation was extended to the synthesis of other compounds containing a few selected β-iodoethoxyl moieties that showed improved stability in the pilot study work. Reference compounds containing the classical iodovinyl unit, as well as those lacking a stabilising β- oxygen atom, were also prepared. The carrier molecules used in this part of the work was a benzamide containing a phenolic oxygen atom which acted as the β-oxygen atom, as well as two heterocyclic amines, benzotriazole and 2-methyl-5-nitroimidazole, in which the β- iodoethoxyl moiety was linked to a secondary nitrogen atom. Various suitable alkylating agents were prepared, chemically linked to the carrier molecules, the resulting intermediate compounds converted into tosylate or triflate iodination precursors and labelled with radioiodine by means of iodide-for-tosylate/triflate exchange. In vitro stability tests of these compounds showed similar trends to those obtained with the model compounds. Moreover, the stability of the stabilised β-iodoethoxyl moiety compared favourably with that of the iodovinyl unit, especially when incorporated into a heterocyclic amine. The results of this study have shown that some of the radioiodinated compounds synthesized in this work, especially the nitroimidazole derivatives, have the potential to be considered as novel radiopharmaceuticals. / AFRIKAANSE OPSOMMING: 'n Studie is onderneem om die radiochemiese stabiliteit van die β-jodium-etoksi-eenheid te ondersoek. Dié eenheid is 'n relatief nuwe prostetiese groep wat in radiofarmaseutiese chemie gebruik word. Die suurstofatoom wat in 'n β-posisie relatief tot die radiojodiumatoom voorkom, oefen 'n stabiliserende invloed op die alifatiese koolstof-jodiumbinding uit. Die ondersoek het met 'n loodsstudie begin deur verskillende modelverbindings te sintetiseer wat 'n β-radiojodium-etoksi-eenheid bevat, asook twee verwysingsverbindings waarin so 'n eenheid ontbreek. Die doel hiermee was om die invloed van verskillende groepe, wat in die omgewing van die β-suurstofatoom voorkom, op die stabiliteit van die eenheid te bepaal. Radiochemiese stabiliteitstoetse is uitgevoer deur middel van inkubering in menslike bloedserum by 37°C. Die resultate het die groter stabiliteit van so 'n eenheid in vergelyking met dié van die verwysingsverbindings aangetoon, en het ook uitgewys dat vertakking van so 'n alifatiese eenheid 'n aansienlike verbetering in die stabiliteit tot gevolg gehad het, veraloor 'n langer periode. Die ondersoek is vervolgens uitgebrei deur verdere verbindings te sintetiseer wat beskik oor bepaalde uitgesoekte β-jodium-etoksi-eenhede, wat verbeterde stabiliteit in die loodsstudie getoon het. Verwysingsverbindings wat die klassieke jodiumvinieleenheid bevat het, sowel as dié waarin 'n stabiliserende β-suurstofatoom ontbreek het, is ook berei. Die draermolekules wat in hierdie deel van die studie gebruik is, was 'n bensamied met 'n fenoliese suurstofatoom wat as die β-suurstofatoom gedien het, sowel as twee heterosikliese amiene, bensotriasool en 2- metiel-5-nitroimidasool, waarin die β-jodium-etoksi-eenheid aan 'n sekondêre stikstofatoom geheg is. Verskillende geskikte alkileermiddels is berei, aan die draermolekules geheg, die tussenprodukte omskep in tosilate of triflate en met radiojodium gemerk deur middel van jodium-vir-tosilaatltriflaat-uitruiling. Stabiliteitstoetse van hierdie verbindings in bloedserum het soortgelyke tendense as dié van die aanvanklike modelverbindings getoon. Daarbenewens het die stabiliteit van die gestabiliseerde β-jodium-etoksi-eenheid gunstig vergelyk met dié van die jodiumviniel-eenheid, veral wanneer dit deel gevorm het van 'n heterosikliese amien. Die resultate van die studie het getoon dat sommige van die radiogejodeerde verbindings wat berei is, veral die nitroimidasoolderivate, die potensiaal het om as nuwe radiofarmaseutiese verbindings gebruik te kan word.

To ιχνοστοιχείο Ιώδιο είναι απαραίτητο συστατικό των θυρεοειδικών ορμονών. Οι θυρεοειδικές ορμόνες συντίθενται και εκκρίνονται στην κυκλοφορία από το θυρεοειδή αδένα και είναι απαραίτητες για τη διαφοροποίηση, την ανάπτυξη και το πολλαπλασιασμό των ανθρώπινων (και όχι μόνο) κυττάρων. Η αναγκαία ποσότητα Ιωδίου για τον οργανισμό προσλαμβάνεται από τη τροφή. Είναι γνωστό ότι οι κάτοικοι των παραθαλάσσιων περιοχών προσλαμβάνουν διαιτητικώς μεγαλύτερα ποσά Ιωδίου, σε σύγκριση με τους κατοίκους ορεινών περιοχών. Παρόλα αυτά ανεπάρκεια ημερήσιας πρόσληψης Ιωδίου έχει αναφερθεί και σε κατοίκους παραθαλάσσιων περιοχών. Οι διαφορές αποδίδονται σε αυξημένες ποσότητες σε μερικές παράλιες περιοχές εισπνεόμενου αέριου Ιωδίου που προκύπτει από την έντονη παρουσία παράλιων φυκιών πλούσιων σε Ιώδιο. Η ανεπαρκής ή εξεζητημένη διαθεσιμότητα και πρόσληψη Ιωδίου από τον ανθρώπινο οργανισμό μπορεί να οδηγήσει σε διαταραχές της θυρεοειδικής λειτουργίας. Το Ιώδιο εμφανίζει το φαινόμενο της εξάχνωσης και μπορεί να μεταβεί από την στερεή στην αέρια κατάσταση, χωρίς να μεσολαβήσει η υγρή. Χρησιμοποιείται ιδιαίτερα στη φαρμακολογία ως απολυμαντικό και αντισηπτικό μέσο, κυρίως αυτούσιο, με τη μορφή διαλύματος σε αιθυλική αλκοόλη και νερό. Διάλυμα 10% σε νερό ιωδιούχου ποβιδόνης (Betadine) χρησιμοποιείται ως αντισηπτικό στα χειρουργεία. / Our Letter to the Editor entitled "Absence of differences in urinary iodine excretion and thyroid function tests in operating room staff members using or not using iodine-containing antiseptic solutions" refered to a recently published article to Thyroid by Erdogan et al (Vol 23 (3) page 342-345, March 2013).

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An iodine surface layer has been prepared on Ru(poly) and Ru(0001) electrodes by exposure to iodine vapor in UHV and polarizing in a 0.1 M HClO4/0.005 M KI solution, respectively. A saturation coverage of I on a Ru(poly) electrode passivates the Ru surface against significant hydroxide, chemisorbed oxygen or oxide formation during exposure to water vapor over an electrochemical cell in a UHV-electrochemistry transfer system. Immersion of I-Ru(poly) results in greater hydroxide and chemisorbed oxygen formation than water vapor exposure, but an inhibition of surface oxide formation relative that of the unmodified Ru(poly) surface is still observed. Studies with combined electrochemical and XPS techniques show that the iodine surface adlayer remained on top of the surface after cycles of overpotential electrodeposition/dissolution of copper on both Ru(poly) and Ru(0001) electrodes. These results indicate the potential bifunctionality of iodine layer to both passivate the Ru surface in the microelectronic processing and to act as a surfactant for copper electrodeposition. The electrodeposition of Cu on Ru(0001) or polycrystalline Ru was studied using XPS with combined ultrahigh vacuum/electrochemistry methodology (UHV-EC) in 0.1 M HClO4 with Cu(ClO4)2 concentrations ranging from 0.005 M to 0.0005 M, and on polycrystalline Ru in a 0.05M H2SO4/0.005 M CuSO4/0.001 M NaCl solution. The electrochemical data show well-defined cyclic voltammograms (CV) with a Cu underpotential deposition (UPD) peak and overpotential deposition (OPD) peak. XPS spectra of Ru electrodes emersed from perchloric acid solution at cathodic potentials indicate that ClO4- anions dissociate to yield specifically adsorbed Cl and ClOx species. Subsequent Cu deposition results in the formation of a thin, insoluble Cu(II) film with Cu(I) underneath. In contrast, similar deposition on polycrystalline Ru in the sulfuric acid/Cu sulfate solution with NaCl added yields only Cu(0), indicating that the formation of Cu(II) and Cu(I) involves both Cl and perchlorate interactions with the deposited Cu. A pre-adsorbed layer of iodine on the Ru(0001) surface inhibits perchlorate dissociation in iodide-free electrolyte and leads to the deposition of Cu(0) in the perchlorate bath. XPS depth profile analysis demonstrates that the iodine monolayer "floats" on top of the deposited film, in agreement with previous results, effectively protecting the Cu film from air oxidation.

Diaryliodonium salts offer potential as novel reagents for arylation chemistry. An overall goal and successful outcome of this work has been to further understanding of diaryliodonium salt chemistry by developing practical methods that enable chemists more convenient access to these reagents, for the purpose of reaction development. To this end a robust and convenient preparation method has been developed and resulted in novel commercially available diaryliodonium salts. The remainder of the work described, has focused on understanding the parameters important to diaryliodonium mediated arylation and has resulted in a solid framework that multiple future development efforts can build upon. A strategy adopted throughout this work was to use multivariate methodologies such as Design of Experiments (DoE). Applicable chapters show the results of optimization studies that were carried out using DoE, during the course of this work. Additionally, the desire to further realize the potential that DoE has to offer inspired of a search for parameters to study fundamental reactivity. Chapter 2 details the development of a practical diaryliodonium salt synthesis that is convenient, facile, and economical. A detailed procedure is also included and was drafted to the requirements for publication in the journal Organic Synthesis. Finally, limitations and future directions of the method are discussed. Chapter 3 describes studies aimed at understanding the role of the counter anion; a very practical counter anion screening method is presented. Future directions are discussed and include detailed characterization of diaryliodonium salts by NMR. Chapter 3 also describes a practical, scalable, and rapid salt exchange method developed during this work. Chapter 4 describes the results obtained in studying an azidation reaction via solubility parameters. All Supporting Information, including characterization data and experimental details, are provided in Chapter 5.

Understanding energy transfer processes is an essential prerequisite for the deep understanding of all chemical processes. This thesis investigates the process of vibrational relaxation (or deexcitation) of highly vibrationally and electronically excited molecular iodine (I2) induced by very low energy collisions in a supersonic free jet with six foreign gases. In an investigation of the state-to-field relaxation of I2 (B 3II+ou, v = 16) induced by collisions with He at temperatures of 2 to 12 K we find that the absolute relaxation rates are an order of magnitude smaller than those at 300 K and that the explanation of the magnitudes of these rates does not require enhancement due to low energy orbiting resonances. We find that the rates scale well with estimated collision encounter rates that account for the attractive part of the intermolecular potential. A second investigation with a much wider scope explores vibrational relaxation from v = 21 to 24 with six foreign gases: He, Ne, Ar, H2, D2 and N2. For this investigation a new type of experimental procedure has been designed and implemented that records a detailed and complete map of the fluorescence from B3II+ouI2 that is resolved with respect to both fluorescence frequency and time. These not only yield state-to-field rates, but coupled with a novel deconvolution method for growth curve fitting, yield absolute state-to-state rates for vibrational relaxation processes with Av=-1, -2, -3 and -4. The dependence of the relaxation rates on the collision partner, temperature and Av are discussed. An exponential dependence on the vibrational energy gap may be adequate to characterise the Av dependence of vibrational relaxation. The frequency resolution of the experimental data also reveals that some of the energy released by vibrational de-excitation is transferred to the rotation of the I2 molecule. We find this process is best characterised by an exponential dependence on the change of I2 angular momentum and that its extent scales with the mass of the collision partner. Measurements of the low-energy collision-induced quenching of B 3II+ouI2 are also reported for all six foreign gases. The possibility arises from the rates that the mechanism for quenching by H2 and D2 at low temperatures is different to that of the other gases and to that for H2 and D2 at high temperatures.

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