Radioyodo como tratamiento de hipertiroidismo en un paciente en hemodiálisis: Caso clínico / Treatment of hyperthyroidism with radioiodine during hemodialysis: Report of one case

Although radioiodine (131-I) can be used as treatment of hyperthyroidism for patients in hemodialysis, its use is limited and the experience is mainly related to differentiated thyroid carcinoma. We report a 58 years old female on hemodialysis with recurrent hyperthyroidism after propylthiouracil treatment. She was successfully treated with 131-I and four months after the intervention her euthyroid state was confirmed. We measured 131-I activity in blood, dialysate liquid and other waste products, as well as patient radiation exposure rates. We found that 131-I elimination was prolonged through time with no major dependence on hemodialysis, as opposed to the elimination of 131-I in patients with thyroid carcinoma. This was probably due to high radiotracer uptake in hyper functioning thyroid tissue. Conversely, radiation content in dialysate wastes or equipment was minimal. Furthermore, the rate of both environmental exposure and exposure of nursing staff in charge of hemodialysis sessions, was minimal and met international security standards. In conclusion, I-131 therapy showed both appropriate effectiveness and safety in this case and may be considered as a suitable treatment alternative to thyroidectomy when antithyroid drugs are unsuccessful.

Abnormal radioiodine uptake on post-therapy whole body scan and sodium/iodine symporter expression in a dermoid cyst of the ovary: report of a case and review of the literature

In patients affected by differentiated thyroid cancer, the whole-body scan (WBS) with 131-radioiodine, especially when performed after a therapeutic activity of131I, represents a sensitive procedure for detecting thyroid remnant and/or metastatic disease. Nevertheless, a wide spectrum of potentially pitfalls has been reported. Herein we describe a 63-year-old woman affected by follicular thyroid cancer, who was accidentally found to have an abdominal mass at post-dose WBS (pWBS). pWBS showed abnormal radioiodine uptake in the upper mediastinum, consistent with lymph-node metastases, and a slight radioiodine uptake in an abdominal focal area. Computed tomography revealed an inhomogeneous mass in the pelvis, previously unrecognized. The lesion, surgically removed, was found to be a typical dermoid cyst of the ovary, without any evidence of thyroid tissue. By immunohistochemistry, a moderate expression of the sodium-iodine symporter (NIS) was demonstrated in the epithelial cells, suggesting a NIS-dependent uptake of radioiodine by the cyst.

Monitoring Nonsurgical and Surgical Root Canal Treatment of Teeth with Primary and Secondary Infections

The aim of this study was to monitor nonsurgical and surgical root canal treatment (RCT) of teeth with primary and secondary infections and apical periodontitis (AP). This prospective clinical study comprised the treatment of 80 patients with primary and persistent secondary infections and AP. Of this initial sample, forty patients did not return. Periapical index using cone beam computed tomography scans (CBCTPAI) was used to aid diagnosis, planning and to determine the better therapeutic strategy. Twenty patients (26 teeth) diagnosed with primary infection and AP received conventional RCT and were followed up for 10 to 36 months. Twenty patients (31 teeth) diagnosed with persistent secondary infection were submitted to periapical surgical and followed up for 6 to 30 months. The results showed RCT successful in 19/26 cases with complete AP healing (5/26 with partial repair) in 10-36 months of follow up. For the surgically managed cases, effectiveness of surgical therapy was detected in 10/31 cases with complete healing (10/31 cases with partial repair) within 6-30 months follow up. The return of patients for clinical and radiographic follow-up, and obedience to the proposed time period was very short from ideal. The levels of success in both therapeutic protocols were high. RCT failures were detected even with rigorous standard clinical protocols.

O objetivo do estudo foi monitorar tratamentos de canais radiculares (TCR) convencionais e com auxílio de cirurgia periapical. Este estudo prospectivo constituiu de 80 pacientes portadores de infecções primárias e secundárias persistentes e periodontite apical (PA). O índice periapical utilizando tomografia computadorizada de feixe cônico (CBCTPAI) foi utilizado como auxiliar no diagnóstico, planejamento e para determinar a melhor estratégia terapêutica. Apenas 40 pacientes retornaram para o TCR. Em 20 pacientes (26 dentes) com diagnósticos de infecções primárias e PA foram feitos TCR convencionais e monitoramentos por 10 a 36 meses. Em 20 pacientes (31 dentes) com diagnósticos de infecções secundárias persistentes foram submetidos a procedimentos cirúrgicos e acompanhamentos durante 6 a 30 meses. Os resultados mostraram TCR bem sucedidos em 19 de 26 casos, com curas completas das PA (5 de 26 com reparação parcial) em controles de 10 a 36 meses. Para os casos de tratamentos cirúrgicos foram detectadas eficácias das terapêuticas cirúrgicas em 10 de 31 casos com curas completas (10 de 31 casos com reparação parcial) em controles de 6 a 30 meses. O retorno dos pacientes para controle clínico e radiográfico e a obediência ao período de tempo proposto está muito aquém do ideal. Os níveis de sucesso em ambos os protocolos terapêuticos se mostraram elevados. Fracassos no TCR foram detectados mesmo utilizando protocolo clínico com rigoroso padrão.

Clinical and laboratory features of children and adolescents with congenital hypothyroidism due to dyshormonogenesis in southern Brazil / Características clínicas e laboratoriais de crianças e adolescentes com hipotireoidismo congênito devido a disormonogênese no sul do Brasil

OBJECTIVE: To characterize the phenotype of patients with congenital hypothyroidism (CH) due to dyshormonogenesis, and to hypothesize on the degree of genetic defect. SUBJECTS AND METHODS: Patients with dyshormonogenesis were subdivided into G1 (radioactive iodine uptake, RAIU > 15%; n = 62) and G2 (RAIU < 15%; n = 32). Thyroglobulin (TG) was measured in all patients; perchlorate discharge test (PDT) was performed in G1; and saliva-to-plasma radioiodine ratio (I- S/P) in G2. RESULTS: Levels of TSH, TT4, and FT4 before treatment and upon diagnosis confirmation were significantly different in both groups, but not between groups. In G1, 27 patients developed goiter; 17 had positive PDT (14%-71% discharge), 11 had TG < 2.5 ng/dL (one with high TSH), and one developed thyroid carcinoma. In G2, four patients developed goiter, and three had low I- S/P. CONCLUSION: These data suggest an iodide organification defect in 17 cases; an iodide transport defect (NIS defect) in three, probable TSH resistance in 10, and a TG synthesis defect in two cases.

OBJETIVO: Caracterizar o fenótipo de pacientes com hipotireoidismo congênito (HC) por disormonogênese e sugerir o nível do defeito genético. SUJEITOS E MÉTODOS: Pacientes com disormonogênese foram subdivididos em G1 (captação de 131I > 15%; n = 62) e G2 (captação < 15%; n = 32). Tireoglobulina (TG) foi dosada em todos, teste de descarga do perclorato (TDP) foi realizado no G1 e relação iodo salivar/sérico (I- S/P), no G2. RESULTADOS: Os valores de TSH, T4T e T4L pré-tratamento e na confirmação do diagnóstico foram significativamente diferentes em ambos os grupos (p < 0,01), mas não entre eles. No G1, 27 pacientes desenvolveram bócio; TDP foi positivo em 17 (descarga de 14%-71%); 11 tiveram TG < 2,5 ng/dL (um com TSH elevado) e um desenvolveu carcinoma de tireoide. No G2, quatro pacientes desenvolveram bócio e três apresentaram baixa I- S/P. CONCLUSÃO: Esses dados sugerem defeito na organificação do iodeto em 17 casos; defeito no transporte do iodeto (defeito na NIS) em três, provável resistência ao TSH em 10 e defeito na síntese de TG em dois.

Clinical Significance of Observation without Repeated Radioiodine Therapy in Differentiated Thyroid Carcinoma Patients with Positive Surveillance Whole-Body Scans and Negative Thyroglobulin

BACKGROUND/AIMS: Currently, there is no consensus on the necessity of repeated radioiodine therapy (RAI) in patients who show iodine uptake in the thyroid bed on a diagnostic whole-body scan (DxWBS) despite undetectable thyroglobulin (Tg) levels after remnant ablation. The present study investigated the clinical outcomes of scan-positive, Tg-negative patients (WBS+Tg-) who did or did not receive additional RAI. METHODS: We retrospectively reviewed 389 differentiated thyroid carcinoma patients who underwent a total thyroidectomy and received high-dose RAI from January 2003 through December 2005. The patients were classified according to surveillance DxWBS findings and TSH-stimulated Tg levels 6 to 12 months after the initial RAI. RESULTS: Forty-four of the 389 patients (11.3%) showed thyroid bed uptake on a DxWBS despite negative Tg levels (WBS+Tg-). There was no difference in clinical and pathological parameters between WBS+Tg- and WBS-Tg- patients, except for an increased frequency of thyroiditis in the WBS+Tg- group. Among the 44 WBS+Tg- patients, 27 subjects were treated with additional RAI; 25 subjects showed no uptake in subsequent DxWBS. Two patients were evaluated only by ultrasonography (US) and displayed no persistent/recurrent disease. The other 17 patients received no further RAI; Eight patients and two patients showed no uptake and persistent uptake, respectively, on subsequent DxWBS. Six patients presented negative subsequent US findings, and one was lost to follow-up. Over the course of 53.2 +/- 10.1 months, recurrence/persistence was suspicious in two patients in the treatment group. CONCLUSIONS: There were no remarkable differences in clinical outcomes between observation and treatment groups of WBS+Tg- patients. Observation without repeated RAI may be an alternative management option for WBS+Tg- patients.

Radioiodine concentration by the thymus in differentiated thyroid carcinoma: report of five cases / Captação do radioiodo pelo timo no carcinoma diferenciado de tireoide: relato de cinco casos

The radioactive iodine has been used with great value as a diagnostic and therapeutic method in patients with differentiated thyroid carcinoma previously submitted to total thyroidectomy. False-positive whole-body scans may occur due to misinterpretation of the physiologic distribution of the radioisotope or lack of knowledge on the existence of other pathologies that could eventually present radioiodine uptake. Thymic uptake is an uncommon cause of false-positive whole-body scan, and the mechanism through which it occurs is not completely understood. The present paper reports five cases of patients with differentiated thyroid cancer who presented a mediastinum uptake of radioiodine in a whole-body scan during follow-up. The patients had either histological or radiological confirmation of the presence of residual thymus gland. It is very important to know about the possibility of iodine uptake by the thymus in order to avoid unnecessary treatment, such as surgery or radioiodine therapy.

O iodo radioativo tem sido utilizado com grande valia como método diagnóstico e terapêutico em pacientes com carcinoma diferenciado de tireoide previamente submetidos à tireoidectomia total. Resultados falso-positivos na pesquisa de corpo inteiro (PCI) podem ocorrer por má interpretação da distribuição fisiológica do radioisótopo ou por não conhecimento da existência de outras patologias que podem eventualmente captar o radioiodo. Captação pelo timo é uma causa incomum de resultado falso-positivo e o mecanismo pelo qual ocorre não é totalmente esclarecido. O presente trabalho relata cinco casos que apresentaram PCI positiva em mediastino durante o seguimento, com comprovação histológica ou tomográfica sugestiva de timo. Ressalta-se a importância do conhecimento dessa possível causa de falso-positivo a fim de se evitar tratamentos desnecessários.

Timo persistente y su implicancia en el seguimiento del cáncer diferenciado del tiroides / Abnormal mediastinal radioiodine uptake due to persistent thymus: report of one case

We report a 37 years old female operated for a multifocal papillarythyroid carcinoma. During her follow up, mediastinal uptake of radioiodine due to a persistent thymus, was detected. Thisis a situation may cause a false positive uptake of radioiodine that may be interpreted as a tumor relapse or metastasis.

Dosis y Factores Gamma de una paciente con 131I / Doses and Gamma factors in a patient with 131I

Mediante métodos Monte Carlo se calcularon las dosis en los órganos internos de una mujer, con tres meses de embarazo, debidas al radioiodo captado por su tiroides, así como a 1 metro de la glándula. Se utilizó un modelo tridimensional del cuerpo de la mujer y mediante Monte Carlo, los fotones de radioiodo se transportaron isotrópicamente desde la tiroides hacia todo el cuerpo y se calculó la dosis absorbida por sus órganos internos. También se determinó el Kerma en aire (K) y la dosis equivalente ambiental (H*(10)) a 1 m de la glándula. Se determinaron dos factores de actividad a dosis, también llamados Factores Gamma, que permiten estimar la dosis que la paciente produce a personas a su alrededor. De la radiación gamma que emite el 131I en la tiroides se encontró que el timo recibe la mayor dosis mientras que el útero es el órgano que menor dosis recibe. Los factores gamma determinados fueron: ΓKAire = 52.06 μGy-m2-h-1-GBq-1, y ΓH*(10) = 67.72 μSv-m2-h-1-GBq-1. La distribución de la dosis absorbida por los órganos internos se atribuye a la distancia relativa entre la tiroides y los otros órganos, al blindaje inter-órganos, su tamaño y a su composición elemental. Los factores ΓKAire y ΓH*(10) permiten estimar la exposición que la paciente produce sobre el personal a su alrededor. Con esto, el médico nuclear, el físico médico o el responsable de la seguridad radiológica en el hospital pueden dar indicaciones mas precisas sobre el comportamiento de las personas en torno al paciente.

Valores normales de captación de 131Yodo de 2 y 24 horas / Normal 131Iodine uptake values at 2 ano 24 hours

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 percent±1.8 percent (range: 2.3-12.0) at 2 h and 16.2±4.8 percent (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 percent, respectively, (p <0.02). At 24 h, the figures were 17.3±4.5 and 15.0±4.9 percent, respectively (p =0.01). Compared to their younger counterparts, radioactive iodine uptake was lower among volunteers older than 40 years, at 2 h (5.0±1.7 and 6.0±1.8, respectively, p <0.02) and at 24 h (14.9±4.4 and 17.6±4.9 percent, respectively, p <0.01). Conclusions: Normal thyroid uptake values in adults are influenced bygender and age. Normal thyroid iodine uptake values are slightly higher in females. Iodine thyroid uptake values decrease slightly in subjects aged more than 40years.

Cinco diferentes tipos de imágenes gammagráficas tiroideas en pacientes con enfermedad de Graves tratados con 131I en el Paraguay / Five different gammagraphic images of thyroid gland in patients with Grave’s disease treated with 131I in Paraguay

Thyroid disease is frequent in Paraguay, a country with a prevalence of goiter 48,6 percent in general population located in the center of South America. Grave’s disease constitutes the most common thyroid hyperfunction observed whose treatment can be carried out with medication (propiltiouracil, metimazol, etc.), surgery or iodine 131(131I) We analyzed 70 patients this type of hyperthyroidism treated with the 131I, in its clinical aspect pre and post treatment, ultrasound and nuclear scan findings of the gland thyroid, the hormonal respond Ft4, T3, TSH, thyroid antibodies TPOab, TGab, TRab. Besides the diffuse classic image observed in the thyroid scan and by ultrasonography of the gland, in Grave’s disease, 4 types of images were identified with nodules (multinodular, hot nodule, cold nodule and miliar). The group with diffuse increase in size form was the most numerous (50 percent) continued by the variety multinodular (30 percent), Marin-Lenhart’s Sx (hot nodule) 14 percent, miliary 3 percent, and cold nodule 3 percent. Three months after the treatment with the radioiodine was observed the decrease of the size and thyroid volume in 68 percent of the patients, thyroid uptake with 131I diminished in 75 percent. All patients had an increase of weight of 20 percent and 87 percent of then were feminine. The signs and symptoms were normalized in 88,5 percent of the patients. The levels of FT4 were normalized in 73, 8 percent, T3 in 66 percent, TSH in 47,7 percent, TPOab in 83 percent, TGab in 90 percent, and TRab in 84 percent. A received a single dose of 131I was used it in 93 percent of the patient The cost of the 131I in the Clinic Hospital was half of the cost of the surgery, and at private level the fourth part but cheap.

A computer program for single-injection tracer clearance from one, two, or many blood samples

A computer program based on a Bayesian statistical model has been developed for calculating tracer clearance from any number of plasma samples drawn at arbitrary time intervals. Bayesian prior parameters were calculated from clinical data for Tc99m-MAG3, Tc99m-EC, I131-OIH, Tc99m-DTPA, and Yb169-DTPA and then used to calculate clearance from prospective data. Clearance estimates using only one or two plasma samples were found to closely approximate the results of using multiple samples. When only one or a few samples are available, the program supplements the observed data by a Bayesian prior probability distribution (based on prior clinical measurements) to achieve agreement with multisample clearance. When many points are available, the observed data overwhelm the prior probability, and results approach those of conventional curve fitting but with less sensitivity to bad data points and less risk of fitting failure.

Tratamento do carcinoma diferenciado da tireóide com iodo-131: intervenções para aumentar a dose absorvida de radiação / Radioiodine therapy for differentiated thyroid carcinoma: methods used to increase the radiation absorbed dose

OBJETIVO: Analisar medidas tomadas para aumentar a dose de radiação absorvida (DOSE) durante o tratamento do carcinoma diferenciado da tireóide (CDT) com iodo-131. MÉTODOS: As abordagens para aumentar a DOSE na radioiodoterapia são: redução da competição com iodo não-radioativo, estímulo da captação/retenção celular e aumento da atividade administrada. Revisaram-se os fundamentos e resultados de cada um destes métodos. RESULTADOS: Apesar de ser difícil confirmar aumento de sobrevida, existe relação direta entre a DOSE e a resposta no CDT. Diferentes abordagens permitem o aumento da DOSE nos tecidos, inferindo-se uma possível melhora na resposta dos tumores ao tratamento com iodo-131. Apesar do prognóstico relativamente benigno da doença, a melhoria da resposta é importante nos casos de alto risco, em que as alternativas de tratamento são limitadas. CONCLUSÕES: As intervenções descritas permitem aumentar a DOSE durante o tratamento do CDT, podendo ser empregadas para casos de alto risco.

Padronização de valores de captação tiroidiana com 123I / Reference values for thyroid 24 hours 123I uptake

Com o objetivo de padronizar valores de referência para captação tiroidiana (CAPTIR) com 123I, analisamos 475 pacientes que realizaram dosagens de T4 livre e TSH e exames de CAPTIR 24h após a administração de 123I. Separamos os pacientes em 3 grupos: hipertiróideo, normal e hipotiróideo, de acordo com os resultados do T4 livre e TSH. Calculamos as médias e os desvios-padrão (DP) dos valores de captação, realizamos testes t não-pareados e calculamos curvas ROC para definir os melhores valores de CAPTIR para separar os grupos. As médias e DP dos valores de captação foram: hipertiróideo (36,5 por cento ± 16,5 por cento), normal (14,4 por cento ± 5,48 por cento) e hipotiróideo (13,7 por cento ± 7,5 por cento). O teste t não-pareado mostrou diferença significativa entre os grupos hipertiróideo e normal (p< 0,01), sem diferença significativa entre os grupos normal e hipotiróideo (p= 0,55). O valor de captação 23 por cento apresentou melhor relação sensibilidade (80 por cento) / especificidade (93 por cento) para separar o grupo normal do hipertiróideo. A curva ROC não mostrou bons resultados para a separação do grupo normal do hipotiróideo. Em conclusão, o limite superior da normalidade para CAPTIR pode ser estabelecido em 23 por cento. Não foi possível estabelecer limite inferior de normalidade, devido à grande sobreposição dos valores de captação dos grupos hipotiróideo e normal.

Radioiodine kinetics and thyroid function following the universal salt iodization policy.

BACKGROUND: Universal salt iodization was introduced in Delhi in 1989. The present study quantifies the change in iodine kinetics as a result of this. The previous values were reported 10-30 years earlier, when Delhi was iodine deficient. METHODS: Thirty subjects (18 men and 12 women, 17-48 years of age) who were residents of Delhi and had no thyroid disorder, were recruited from our outpatient clinic in 1999. The 24-hour urinary excretion of iodine and the iodine content of salt consumed at home by these subjects were estimated. Kinetic studies of iodine using radiotracer 131I were done to determine thyroid iodine clearance, renal iodine clearance, percentage uptake and absolute iodine uptake by the thyroid gland, and plasma inorganic iodine. RESULTS: The median 24-hour urinary iodine excretion was 341.3 micrograms. The mean (SD) thyroid uptake of radioactive iodine was 4.9 (2.3)% at 2 hours and 19.1 (8.0)% at 24 hours. The median calculated plasma inorganic iodine was 1.36 micrograms/dl, absolute iodine intake 6.5 micrograms/hour and thyroid iodine clearance was 4.8 ml/minute (geometric means 1.68 micrograms/dl, 8.5 micrograms/hour and 8.1 ml/minute, respectively). The serum thyroid hormones and thyroid stimulating hormone were within normal limits. CONCLUSION: Compared to the values reported 10-30 years ago when the population was iodine deficient, the present urinary iodine excretion, plasma inorganic iodine and absolute iodine intake have increased, while the percentage thyroid uptake of iodine ingested and thyroid clearance have decreased. The lack of change in the serum thyroid hormone levels after 10 years of universal salt iodization indicates that iodine consumption has had no adverse effect on thyroid function in these normal individuals. These changes are consistent with the increase in iodine consumption. Since the iodine ingestion in a community may change with time, assessment of iodine kinetics should be done periodically in different regions of the country.

Gestación y cáncer diferenciado tiroideo / Pregnancy and differentiated thyroid cancer

Se revisaron 24 historias clínicas de gestantes-27 gestaciones y 28 niños- atendidas en la consulta de tiroides del Instituto Nacional de Endocrinología para valorar la repercusión que pudiera tener la administración de I 131 y de hormona tiroidea (HT) en dosis supresiva en mujeres con cáncer diferenciado -no medular- del tiroides (CDT) sobre futuras gestaciones, en cuanto al producto de la gestación y ésta sobre la evolución del CDT. Se les practicó tiroidectomía total a 21 y hemotiroidectomía con istmectomía a 3 y a todas se les administró HT. Se tuvieron en cuenta los siguientes parámetros: edad al primer embarazo posterior al tratamiento del cáncer y comparada con el de población del país, tiempo entre la administración del I131 y la gestación, dosis de radioiodo recibida, tiempo transcurrido entre la gestación y la última evaluación del cáncer y presencia de complicaciones fetales y de recidiva del cáncer. La edad de las gestantes fue x: 28 ñ 6,7 años superior a la correspondiente a la población (p<0,05) y el tiempo de seguimiento posparto x: 7,2 ñ 7,4 años. Se ordenaron las embarazadas en grupo 1-no recibieron I,131 constituido por 13 gestantes con 16 embarazos e igual número de PC; edad al gestarse de x : 2,6 ñ 5,6 años (p<0,05) y tiempo de seguimiento posparto x: 6,3 ñ 8,4 años y grupo 2 -recibieron I131, formado por 11 pacientes con 11 gestaciones y 12 PC., edad al gestarse x: 30 ñ 7,5 años (p<0,05); tiempo entre la ingestión del iodorradiactivo y el embarazo x: 6,7 ñ 3,8 años y la dosis recibida de x: 4,16 ñ 1,66GBq; y el tiempo de seguimiento posparto 5,8 ñ 5,8 años. En el PC se constató bajo peso al nacer en una paciente del grupo 2 con edad de 39 años al gestarse y en el grupo 1, un caso con labio leporino y paladar ojival. No se observaron complicaciones del CDT con posterioridad al embarazo en ninguna de las pacientes. Se consideró que los resultados obtenidos permitían no ser tan radicales al prohibir la gestación en pacientes con cáncer tiroideo y de esa forma evitar que, especialmente las que toman I,131 se gesten a mayor edad

Effect of equine hypothalamic extract on hormone secretion by the adenohypophysis of rats

The effect of Equine Hypothalamic Extract (EHE) on pituitary weight and secretion of TSH, FSH-LH and ACTH was studied in the rat. The pituitary respponse to EHE was assessed by measuring (131) I uptake by the thyroid and by weight changes of the pituituray glands, thyroids, adrenals, ovaries and uteri. (131) I uptake of the thyroid and weights of the pituitary, thyroid, adrenal and uterus increased in the treated rats, whereas ovarian weights were similar to control groups. These findings indicate that the EHE containes hypophysiotropic peptides which can stimulate the secretion of pituitary hormones in the rat.

Nifedipine induced modulations of intra-thyroidal radio-iodine turnover kinetics in euthyroid and thyrotoxic patients.

Nifedipine induced modulations of intrathyroidal radioiodine turnover kinetics has been studied in euthyroid and thyrotoxicosis individuals. Nifedipine has been found to suppress Amax significantly (p < 0.001), while transit kinetics k1 and k2 are not significantly affected. On the contrary, in the patients with thyrotoxicosis post-nifedipine Amax was not significantly different from pre-nifedipine study, while k1 was slightly suppressed (p < 0.05) and k2 was significantly elevated (p < 0.01). Apparently different Ca+2 dependent control mechanisms are operative in euthyroid and thyrotoxic states. Clinical implications of these observations have been discussed.

Repadronizaçäo dos índices de captaçäo tiroidiana de pacientes eutiroidianos com o uso do 131I / Standardzation of thyroid uptake indices in patients with euthyroidism with the use of 131I

Com o objetivo de se repadronizar os índices de captaçäo de I pela tiróide na cidade de Säo Paulo, estudamos 454 pacientes encaminhados a três serviços de medicina nuclear, nos quais realizamos exame clínico e dosagens hormonais (T3, T4 e TSH). Excluímos 254 pacientes (55,9%) por apresentarem dosagens hormonais fora dos padröes de normalidade, por serem menores de 12 anos de idade, portadores de bócio mergulhante, bócio simples e bócio multinodular. Os 200 pacientes restantes (44,1%), considerados eutiroidianos, formaram o grupo de estudo, apresentando o seguinte resultado: captaçäo de duas horas = 3 a 12%; captaçäo de 24 horas = 8 a 32%