Evaluation of thyroxine (T4) and progesterone-17-alpha-OH circadian rhythm in swine females (Sus scrofa domestica - Linnaeus, 1758)

No presente trabalho foram utilizadas quatro fêmeas suínas, adultas, mestiças, não-gestantes e sem sinais clínicos de estro, criadas e mantidas sob condições industriais de criação. Objetivou-se avaliar a ocorrência de ritmicidade biológica circadiana para tiroxina e 17-alfa -OH progesterona. Os ensaios para dosagens hormonais foram executados utilizando-se a técnica de radioimunoensaio (RIE) em fase sólida e para isso foi empregado conjunto de reagentes comerciais (COAT-A-COUNT R). As análises séricas de tiroxina mostraram valores mais elevados ao redor das 15 horas, decrescendo a partir dai até atingir níveis menores no intervalo da zero às 4 horas. Quanto a 17-alfa -OH progesterona, observaram-se níveis mais elevados por volta das 3 horas, decrescendo gradativamente ao longo do dia, até atingir menor concentração no intervalo das 12 às 15 horas.

Testosterone, androstenedione, cortisol, triiodothyronine and thyroxine hormonal profile in neonate male buffaloes

Basic aspects of the hormonal profile of five hormones were studied in neonate male buffaloes. The level of testosterone (T), androstenedione (A), cortisol (C), triiodothyronine (T3) and thyroxine (T4) were determined during the period of 1-6, 7-8, - 9-12, 24, 48, 72 and 96 hours after parturition, using RIA solid phase technique. All hormones studied presented high levels in the neonate animals. The T and A levels were high in the first 1-6 hours post-partum, being 99.6+/-66.6 and 1,301.4+/-887.7 pg/ml, respectively. The T decreased sharply to basal levels (below the analysis limit of detection) within 24 hours while the A reached the basal level within 48 hours with 348.0+/-279.4pg/ml. The C and T4 levels were also high in the first 24-48 hours, which levels were 5.0+/-3.2 and 11.1+/-2.6 mu g/ml, respectively, decreasing gradually and significantly (P<0.01) until 96 hours post-partum, when they approached the basal levels (1.2+/-1.5 and 7.2+/-2.7 mu g/ml, respectively). The concentration of T3 remained elevated during the entire period of sample collection with little variation (P>0.05), with levels of 328.6+/-130.8 and 294.5+/-134.9ng/dl, respectively during 1-6 hours and 96 hours after parturition.

Paracoccidioidomycosis in the region of Botucatu (state of São Paulo, Brazil). Evaluation of serum thyroxine (T4) and triiodothyronine (T3) levels and of the response to thyrotropin releasing hormone (TRH)

T4, T3 and TSH serum levels were measured in 25 patients with paracoccidioidomycosis. Thyroid T3 reserves were measured on the basis of the increase in T3 (ΔT3) 2 h after intravenous injection of 200 μg TRH, and pituitary TSH reserves were measured on the basis of TSH increase (ΔTSH) 20 min after the same injection. Twenty healthy volunteers with no history of thyroid disease were used as controls. When the two groups were compared, the following results were obtained: (a) there was no significant difference in mean T4, T3, ΔTSH between groups; (b) reduced T3 levels were detected more frequently in patients with paracoccidioidomycosis, especially among those with the acute form of the disease or with the severely disseminated chronic form. The results suggest the occurrence of a reduction in peripheral conversion of T4 to T3, but do not indicate the occurrence of hypothyroidism in any of its forms (thyroid, pituitary or hypothalamic). © 1988 Kluwer Academic Publishers.

Human follicle stimulating hormone (hFSH) and thyroxine (T4) in survival maintenance and in vitro growth promotion of caprine preantral follicles

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação dos níveis séricos de triiodotironina (T3) e tiroxina (T4) durante o ciclo estral em marrãs (Sus scrofa domestica - Linnaeus, 1758)

No presente trabalho, foram utilizadas 21 fêmeas suínas, virgens, sexualmente aptas, criadas e mantidas sob condições industriais, para observação dos perfis hormonais séricos de triiodotironina e tiroxina, durante o ciclo estral. As colheitas de sangue foram efetuadas sempre no mesmo intervalo, entre 8 e 10 horas. Cada animal foi submetido a 14 punções venosas, distribuídas nos dias zero, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 21, 22 e 23 do ciclo estral. Consideramos o dia zero como o primeiro dia da fase estral, e o 23º dia como o primeiro do estro subseqüente. Os ensaios para dosagens hormonais foram executados utilizando-se a técnica de radioimunoensaio (RIE) em fase sólida e para isso foi empregado conjunto de reagentes comerciais (Coat-A-Count®). Para o hormônio triiodotironina foram observados valores altos no 1º e 23º dia e valor mínimo no 12º dia do ciclo estral. O hormônio tiroxina apresentou valores que oscilaram entre 2,42 e 3,74 mig/dl.

Somatotrophic and thyroid hormones around the onset of lay in broiler breeders under different conditions

Somatotrophic and thyroid hormones were determined around the onset of reproduction in broiler breeders reared in two different housing systems [dark, close-sided house (CH) and conventional, open-sided house (OH)]. In both groups age-related changes were obvious for thyroxine (T-4), growth hormone (GH) and insulin-like growth factor (IGF-1); levels of T-4 decreased, especially between 24 and 28 weeks in both groups; concomitantly GH sharply increased over the same period. A transient peak in triiodothyronine (T-3) occurred between 25 and 27 weeks. The effect of housing was only present after the onset of lay. Between weeks 27-28 and the end of the period studied, the CH group showed higher levels of GH and T-3 but lower T-4 levels as compared to the OH group. A significant increase in GH after onset of lay, without any significant rise in T-3 or in IGF-I, could point to a relative insensitivity to high plasma GH levels. Changes at GH receptor level, together with an increased pituitary GH secretion and/or decreased GH turnover may be expected. This may indicate that hypothalamo-pituitary changes at the onset of lay not only imply changes of gonadotrophic cell function, but also other hormonal axes. The relatively decrease in T-4 without changes in T-3, may point to a decrease in the activity of the thyrotropic axis.

Cold-induced enhancement of avian uncoupling protein expression, heat production, and triiodothyronine concentrations in broiler chicks

The relationships among avian uncoupling protein (avUCP) mRNA expression, heat production, and thyroid hormone metabolism were investigated in 7-14-day-old broiler chicks (Gallus gallus) exposed to a low temperature (cold-exposed chicks, CE) or a thermoneutral temperature (TN). After 7 days of exposure, CE chicks exhibited higher heat production (+83%, P < 0.01), avUCP mRNA expression (+20%, P < 0.01), and circulating triiodothyronine (T-3) levels (+104%, P = 0.07) for non-statistically different body weights and feed intake between 3 and 7 days of exposure as compared to TN chicks. Plasma thyroxine (T-4) concentration was clearly decreased in CE chicks (-33%, P = 0.06). The lower hepatic inner-ring deiodination activity (-47%) and the higher renal outer-ring deiodination activity (+75%) measured in CE compared to TN chicks could partly account for their higher plasma T3 concentrations. This study describes for the first time the induction of avUCP mRNA expression by low temperature in chickens, as it has been previously shown in ducklings, and supports the possible involvement of avUCP in avian thermogenesis. (C) 2003 Elsevier B.V. (USA). All rights reserved.

Perfil dos hormônios da tireoide em pacientes com câncer de mama em estado de menopausa

Objective: The aim of this study was to determine thyroid hormone (TH) profile in postmenopausal patients with breast cancer (BC). Subjects and methods: 12 CaM patients stages I or II, without interventions that could interfere with tumor progression were selected, as well as and a control group with 18 postmenopausal women without CaM. We measured serum anti-thyroperoxidase antibody (TPOAB), thyroid-stimulating hormone (TSH), free thyroxine (T4L), estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH), before and after surgery, besides immunohistochemistry for estrogen (ER) and progesterone (PR) receptors. Results: Four patients with CaM showed changes in thyroid hormone profile: two had hyperthyroidism, one hypothyroidism, and one was positive for TPO-AB. All of them positive for ER and PR.TSH levels in breast cancer patients were not different from levels found in the control group (1.89 +/- 1.56 vs. 2.86 +/- 3.12 mIU/mL), but the levels of T4L in patients with CaM were statistically higher than those of the control group (1.83 +/- 0.57 vs. 1.10 +/- 0.20 ng/dL). Conclusion: These results reinforce the need for assessment of thyroid status in CaM patients, since in the absence of E2, changes in clinical HTs can act in E2-controlled processes. Arq Bras Endocrinol Metab. 2012;56(4):238-43

Síndrome nefrótica primária grave em crianças: descrição clínica e dos padrões histológicos renais de seis casos

Os autores relatam os casos de seis crianças com síndrome nefrótica primária grave de padrão histológico renal incomum na rotina cotidiana dos nefrologistas e patologistas. O diagnóstico da doença foi realizado nas faixas etárias de 3 a 9 meses de idade (n = 4), aos 2 anos e 4 meses (n = 1) e aos 11 anos (n = 1). Um paciente foi prematuro, duas pacientes eram irmãs e seus pais eram primos de primeiro grau. Todos apresentavam edema generalizado; dois pacientes apresentavam desnutrição e hipotireoidismo e dois apresentavam hipertensão arterial e insuficiência renal. A histologia renal mostrou esclerose mesangial difusa (n = 3), proliferação mesangial (n = 2) e síndrome nefrótica do tipo finlandês (n = 1). Quatro pacientes faleceram, as causas de óbito foram infecção (n = 2), insuficiência renal (n = 1) e acidose metabólica (n = 1). Entre os sobreviventes, um paciente foi tratado com vitaminas, tiroxina, captopril e indometacina, apresentando aumento da albumina sérica e melhora do crescimento. O outro paciente apresentava insuficiência renal terminal, sendo tratado com diálise e transplante renal.

Facial paralysis associated to hypothyroidism in a dog

The hypothyroidism is the most commonly endocrinopathy in dogs, that occurs preferentially in middle-aged pure breed. The clinical signs associated with hypothyroidism are variable, many times non-specific, including metabolical, dermatological or cardiovascular. The main laboratorial findings are non-regenerative anemia and hypercholesterolemia. Hyponatremia, increase on alanine transferase and alkaline phosphatase activity also can be observed in a lower frequency. There are some reports of peripheral neuropathies caused by hypothyroidism, but the pathophysiology of this process is still unknown. There are specific diagnostic tests that can be used to help diagnose hypothyroidism, and those should be aligned together with the animal's clinical symptoms. The thyroxine stimulating hormone, and free and total thyroxine concentrations are the most used tests. A Pit Bull dog, female, over weighted, was treated presenting left facial paralysis. Thyroid function tests confirmed hypothyroidism. The animal was treated with hormonal replacement and there was improvement in clinical signs in 40 days, confirming that hypothyroidism was facial paralysis' cause.

Ritmo Circadiano de Triiodotironina (T3) e Tiroxina (T4) Plasmática em Ovelhas Ideal durante o Anestro Estacional

The objective was to determine the plasma levels of the triiodothyronine (T-3) and thyroxine (T-4), in six Ideal ewe sheeps during seasonal anoestrus, by radioimmunoassay. The blood samples were collected from the jugular vein catheter over a period of 24 hours, at 2-h intervals (12, 14, 16, IX, 20, 22, 24, OZ, 04, 06, OX, and 10 hours). II was used analysis of variance for data adjustments, and the decomposition of the collected periods in non-orthogonal polynomial. It was observed a crescent linear effect of the T-4 plasma levels, presenting lower level of 49.60+/-11.41 and higher level of 76.99+/-10.0 ng/ml, at fourth and last blood samples collection, respectively. T-3 plasma levels showed a significant cubic response during 24 hours, with the highest value of 0.94+/-0.20 ng/ml at the end of the the study. In conclusion, thyroidal hormones levels were lower in the first blood samples collection, increasing progressively during the night, reaching the highest levels at the morning period.

Empenamento, níveis hormonais de triiodotironina e tiroxina e temperatura corporal de frangos de corte de diferentes genótipos criados em diferentes condições de temperatura

Estudou-se o empenamento, os níveis hormonais de Triiodotironina (T3) e Tiroxina (T4) e a temperatura corporal de frangos criados em diferentes temperaturas. Foram alojados 180 pintainhos Cobb 500 e 180 pintainhos ISA Label JA57, em temperaturas termoneutra, quente ou fria. O delineamento utilizado foi inteiramente ao acaso, em modelo fatorial 2 x 3 (2 linhagens e 3 temperaturas) com 8 repetições. Houve um aumento das concentrações de T3, nas aves criadas no frio, e uma redução no calor. Também no calor, os frangos ISA Label apresentaram níveis mais altos de T4. As aves Cobb apresentaram uma redução de T4 no calor ou no frio aos 42 dias e no calor aos 21 dias de idade. Houve menor empenamento aos 42 dias, quando os frangos foram criados em alta temperatura e um menor empenamento das aves ISA Label, quando comparadas aos frangos Cobb. As aves criadas no calor apresentaram maior temperatura corporal. Os frangos Cobb apresentaram um aumento na sua temperatura interna, quando criados em ambiente quente. Já os frangos da linhagem ISA Label mantiveram sua temperatura interna, independentemente da temperatura ambiente. É possível concluir que a temperatura ambiente afeta o empenamento dos frangos de corte de linhagens de rápido ganho de peso, que também apresentaram menor tolerância ao calor, demonstrada através de uma maior temperatura corporal e temperatura interna.

Circadian and circannual rhythms of T3 and T4 secretions in Polwarth-Ideal rams

Plasma concentrations of triiodothyronine (T-3) and thyroxine (T-4) in five adult Polwarth-ldeal rams located at latitude 22degrees51 'S and longitude 48degrees26'W were evaluated every 2 months for 1 year (June, August, October, December, February, April). Blood collections were made at 2 h intervals for 24 h in each month, and hormone determinations were by radioimmunoassay. Means of T-3 (97.52 +/- 21.45 ng/dL) and T-4 (4.30 +/- 0.94 mug/dL) varied in peaks throughout the 24 h period with the highest concentrations occurring in the afternoon (16:30 and 14:30 h, respectively), and throughout the year where the highest levels were during months of long daylengths (October, December, February). Results suggest circadian and circannual rhythms in thyroid hormone secretion may be present in rams kept relatively close to the equator. (C) 2002 Published by Elsevier B.V. B.V.

Concentrações plasmáticas de testosterona, triiodotironina (T3) e tiroxina (T4) em bodes submetidos ao estresse calórico

Para verificar o efeito do estresse calórico (EC) nas concentrações plasmáticas de testosterona, triiodotironina (T3) e tiroxina (T4), oito bodes, das raças Saanen (n=4) e Alpina (n=4), foram mantidos em câmara bioclimática, sob condições de termoneutralidade (13,0ºC a 26,7ºC) durante 30 dias e, após um período (60 dias) de descanso, submetidos ao EC (23,7ºC a 34,0ºC) por 30 dias. Para minimizar as variações sazonais nos perfis hormonais devido ao fotoperíodo, durante toda fase experimental, incluindo a de adaptação em condições de termoneutralidade (30 dias), o fotoperíodo foi controlado utilizando-se alternância de dias longos (16h de luz e 8h de escuro) e de dias curtos (8h de luz e 16h de escuro) a cada 30 dias. As amostras de sangue foram coletadas duas vezes por semana durante cinco semanas. No conjunto das raças, o EC não influenciou (P>0,05) as concentrações de testosterona (1,8±0,2 vs 1,3±0,2ng/ml) e nem a de T4 (52,7±2,8 vs 50,0±2,8ng/ml). Houve declínio (P<0,01) das concentrações de T3 nos animais submetidos ao experimento (1,3±0,1 vs 1,0±0,1ng/ml), mas a redução foi observada somente nos bodes Saanen. em ambas as raças, as concentrações de T3 e T4 variaram (P<0,01) conforme o dia da coleta das amostras de sangue. O EC foi suficiente para produzir uma resposta fisiológica com redução das concentrações plasmáticas de T3 em bodes das raças Saanen, mas não da raça Alpina, assim como não foi capaz de alterar os níveis plasmáticos de testosterona e nem de T4.