Thesis (Ph. D.)--University of Chicago, 1921. / "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from the Journal of biological chemistry, vol. XLV, no. 2, 1921; vol. LIV, no. 1, 1922; the American journal of physiology, vol. LVI, no. 1, 1921." Bibliography: p. 181, 18.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 53-55). Also available in electronic version.

Thesis (PH. D.)--University of Chicago, 1921. / "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from the Journal of biological chemistry, vol. XLV, no. 2, 1921; vol. LIV, no. 1, 1922; the American journal of physiology, vol. LVI, no. 1, 1921." Bibliography: p. 181, 18. Also available on the Internet.

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The pulse technique was employed to measure velocities of longitudinal and transverse mechanical waves in solid iodine at ultrasonic frequencies. Pulses were produced and their echoes displayed by a Sperry Ultrasonic Attenuator Comparator. Transducers for generating the waves were: longitudinal waves, X-cut quartz crystals of 5 and 12 Mcs.; transverse waves, Y-cut quartz crystal of. 5 Mcs. For longitudinal measurements the sample was immersed in baths of liquid helium, liquid nitrogen, solid carbon dioxide, ice, ambient room temperature, and boiling water. No dispersion was found. Four samples were used, but as iodine is anisotropic in many of its physical properties most attention was paid to two amorphous samples which were thought to give representative average values of the properties of iodine. From the values of longitudinal velocity, Young's modulus was calculated. Transverse velocity measurements were made in baths of liquid helium, liquid nitrogen, carbon dioxide, and ambient room temperature. The shear, modulus was determined from the transverse velocity; compressibility was found from Young's modulus and the shear modulus. All these quantities behave much as would be expected of a solid material. The Debye characteristic temperature calculated from the longitudinal and transverse velocities was compared with values calculated from specific heat data and Lindemann melting point formula. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

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 (D.P.H.)--University of Michigan.

Thesis (D.P.H.)--University of Michigan.

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