Base de dados : MEDLINE
Pesquisa : D06.472.931.812 [Categoria DeCS]
Referências encontradas : 32265 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 3227 ir para página                         

  1 / 32265 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28942280
[Au] Autor:Edwards TM; Hamlin HJ; Freymiller H; Green S; Thurman J; Guillette LJ
[Ad] Endereço:Department of Biology, University of the South, Sewanee, TN, USA; Department of Biology, University of Florida, Gainesville, FL, USA; School of Biological Sciences, Louisiana Tech University, Ruston, LA, USA. Electronic address: theamedwards@gmail.com.
[Ti] Título:Nitrate induces a type 1 diabetic profile in alligator hatchlings.
[So] Source:Ecotoxicol Environ Saf;147:767-775, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Type 1 diabetes (T1D) is a chronic autoimmune disease that affects 1 in 300 children by age 18. T1D is caused by inflammation-induced loss of insulin-producing pancreatic beta cells, leading to high blood glucose and a host of downstream complications. Although multiple genes are associated with T1D risk, only 5% of genetically susceptible individuals actually develop clinical disease. Moreover, a growing number of T1D cases occur in geographic clusters and among children with low risk genotypes. These observations suggest that environmental factors contribute to T1D etiology. One potential factor, supported primarily by epidemiological studies, is the presence of nitrate and nitrite in drinking water. To test this hypothesis, female hatchling alligators were exposed to environmentally relevant concentrations of nitrate in their tank water (reference, 10mg/L, or 100mg/L NO -N) from hatch through 5 weeks or 5 months of age. At each time point, endpoints related to T1D were investigated: plasma levels of glucose, triglycerides, testosterone, estradiol, and thyroxine; pancreas, fat body, and thyroid weights; weight gain or loss; presence of immune cells in the pancreas; and pancreatic beta cell number, assessed by antibody staining of nkx6.1 protein. Internal dosing of nitrate was confirmed by measuring plasma and urine nitrate levels and whole blood methemoglobin. Cluster analysis indicated that high nitrate exposure (most animals exposed to 100mg/L NO3-N and one alligator exposed to 10mg/L NO3-N) induced a profile of endpoints consistent with early T1D that could be detected after 5 weeks and was more strongly present after 5 months. Our study supports epidemiological data correlating elevated nitrate with T1D onset in humans, and highlights nitrate as a possible environmental contributor to the etiology of T1D, possibly through its role as a nitric oxide precursor.
[Mh] Termos MeSH primário: Jacarés e Crocodilos/sangue
Diabetes Mellitus Experimental/induzido quimicamente
Diabetes Mellitus Tipo 1/induzido quimicamente
Disruptores Endócrinos/toxicidade
Nitratos/toxicidade
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Jacarés e Crocodilos/crescimento & desenvolvimento
Animais
Glicemia/análise
Diabetes Mellitus Experimental/sangue
Diabetes Mellitus Tipo 1/sangue
Relação Dose-Resposta a Droga
Disruptores Endócrinos/farmacocinética
Monitoramento Ambiental/métodos
Feminino
Hormônios Esteroides Gonadais/sangue
Nitratos/farmacocinética
Tamanho do Órgão/efeitos dos fármacos
Tiroxina/sangue
Triglicerídeos/sangue
Poluentes Químicos da Água/farmacocinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Blood Glucose); 0 (Endocrine Disruptors); 0 (Gonadal Steroid Hormones); 0 (Nitrates); 0 (Triglycerides); 0 (Water Pollutants, Chemical); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170925
[St] Status:MEDLINE


  2 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28460140
[Au] Autor:Samuels MH; Kolobova I; Antosik M; Niederhausen M; Purnell JQ; Schuff KG
[Ad] Endereço:Division of Endocrinology, Diabetes and Clinical Nutrition, Oregon Health & Science University, Portland, Oregon 97239.
[Ti] Título:Thyroid Function Variation in the Normal Range, Energy Expenditure, and Body Composition in L-T4-Treated Subjects.
[So] Source:J Clin Endocrinol Metab;102(7):2533-2542, 2017 Jul 01.
[Is] ISSN:1945-7197
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Purpose: It is not clear whether upper limits of the thyrotropin (TSH) reference range should be lowered. This debate can be better informed by investigation of whether variations in thyroid function within the reference range have clinical effects. Thyroid hormone plays a critical role in determining energy expenditure, body mass, and body composition, and therefore clinically relevant variations in these parameters may occur across the normal range of thyroid function. Methods: This was a cross-sectional study of 140 otherwise healthy hypothyroid subjects receiving chronic replacement therapy with levothyroxine (L-T4) who had TSH levels across the full span of the laboratory reference range (0.34 to 5.6 mU/L). Subjects underwent detailed tests of energy expenditure (total and resting energy expenditure, thermic effect of food, physical activity energy expenditure), substrate oxidation, diet intake, and body composition. Results: Subjects with low-normal (≤2.5 mU/L) and high-normal (>2.5 mU/L) TSH levels did not differ in any of the outcome measures. However, across the entire group, serum free triiodothyronine (fT3) levels were directly correlated with resting energy expenditure, body mass index (BMI), body fat mass, and visceral fat mass, with clinically relevant variations in these outcomes. Conclusions: Variations in thyroid function within the laboratory reference range have clinically relevant correlations with resting energy expenditure, BMI, and body composition in L-T4-treated subjects. However, salutary effects of higher fT3 levels on energy expenditure may be counteracted by deleterious effects on body weight and composition. Further studies are needed before these outcomes should be used as a basis for altering L-T4 doses in L-T4-treated subjects.
[Mh] Termos MeSH primário: Composição Corporal/efeitos dos fármacos
Metabolismo Energético/efeitos dos fármacos
Hipotireoidismo/diagnóstico
Hipotireoidismo/tratamento farmacológico
Tiroxina/administração & dosagem
[Mh] Termos MeSH secundário: Absorciometria de Fóton/métodos
Adulto
Idoso
Antropometria
Estudos Transversais
Exercício/fisiologia
Feminino
Seres Humanos
Masculino
Meia-Idade
Valores de Referência
Índice de Gravidade de Doença
Testes de Função Tireóidea
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1210/jc.2017-00224


  3 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29366748
[Au] Autor:Teixeira RB; Zimmer A; de Castro AL; Carraro CC; Casali KR; Dias IGM; Godoy AEG; Litvin IE; Belló-Klein A; da Rosa Araujo AS
[Ad] Endereço:Laboratório de Fisiologia Cardiovascular, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
[Ti] Título:Exercise training versus T3 and T4 hormones treatment: The differential benefits of thyroid hormones on the parasympathetic drive of infarcted rats.
[So] Source:Life Sci;196:93-101, 2018 Mar 01.
[Is] ISSN:1879-0631
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:AIMS: This study aimed to investigate whether beneficial effects of thyroid hormones are comparable to those provided by the aerobic exercise training, to verify its applicability as a therapeutic alternative to reverse the pathological cardiac remodeling post-infarction. MATERIALS AND METHODS: Male rats were divided into SHAM-operated (SHAM), myocardial infarction (MI), MI subjected to exercise training (MIE), and MI who received T3 and T4 treatment (MIH) (n = 8/group). MI, MIE and MIH groups underwent an infarction surgery while SHAM was SHAM-operated. One-week post-surgery, MIE and MIH groups started the exercise training protocol (moderate intensity on treadmill), or the T3 (1.2 µg/100 g/day) and T4 (4.8 µg/100 g/day) hormones treatment by gavage, respectively, meanwhile SHAM and MI had no intervention for 9 weeks. The groups were accompanied until 74 days after surgery, when all animals were anesthetized, left ventricle echocardiography and femoral catheterization were performed, followed by euthanasia and left ventricle collection for morphological, oxidative stress, and intracellular kinases expression analysis. KEY FINDINGS: Thyroid hormones treatment was more effective in cardiac dilation and infarction area reduction, while exercise training provided more protection against fibrosis. Thyroid hormones treatment increased the lipoperoxidation and decreased GSHPx activity as compared to MI group, increased the t-Akt2 expression as compared to SHAM group, and increased the vascular parasympathetic drive. SIGNIFICANCE: Thyroid hormones treatment provided differential benefits on the LV function and autonomic modulation as compared to the exercise training. Nevertheless, the redox unbalance induced by thyroid hormones highlights the importance of more studies targeting the ideal duration of this treatment.
[Mh] Termos MeSH primário: Terapia por Exercício
Infarto do Miocárdio/tratamento farmacológico
Infarto do Miocárdio/terapia
Sistema Nervoso Parassimpático/efeitos dos fármacos
Condicionamento Físico Animal
Tiroxina/uso terapêutico
Tri-Iodotironina/uso terapêutico
[Mh] Termos MeSH secundário: Animais
Ecocardiografia
Fibrose
Hipertrofia Ventricular Esquerda/diagnóstico por imagem
Hipertrofia Ventricular Esquerda/etiologia
Hipertrofia Ventricular Esquerda/patologia
Masculino
Infarto do Miocárdio/diagnóstico por imagem
Estresse Oxidativo/efeitos dos fármacos
Sistema Nervoso Parassimpático/fisiopatologia
Proteínas Proto-Oncogênicas c-akt/biossíntese
Proteínas Proto-Oncogênicas c-akt/genética
Ratos
Ratos Wistar
Sistema Nervoso Simpático/efeitos dos fármacos
Sistema Nervoso Simpático/fisiopatologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
06LU7C9H1V (Triiodothyronine); EC 2.7.11.1 (Akt2 protein, rat); EC 2.7.11.1 (Proto-Oncogene Proteins c-akt); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE


  4 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28462486
[Au] Autor:Diatroptov MЕ; Diatroptova MA
[Ad] Endereço:Research Institute of Human Morphology, Moscow, Russia.
[Ti] Título:Infradian Biorhythm of Thyroid Hormone Concentrations in Mammals and Birds.
[So] Source:Bull Exp Biol Med;162(6):815-819, 2017 Apr.
[Is] ISSN:1573-8221
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Studies of the dynamics of thyroid hormone concentrations in the blood revealed a 3-day rhythm that significantly manifested in male Wistar rats and Chinchilla rabbits during intensive growth and in common starlings (Sturnus vulgaris) during moult. Synphasic 3-day biorhythms of thyroid hormonal activities were found in these animals, which attested to an external synchronizer of this biorhythm common for mammals and birds. The maximum level of thyroid hormones coincided with the extrema of daily fluctuations of the Earth rotation velocity, as a result of which this external factor or another factor closely related to it seemed to be involved in synchronization of the 3-day infradian biorhythm of thyroid hormones in mammals and birds.
[Mh] Termos MeSH primário: Corticosterona/sangue
Passeriformes/fisiologia
Periodicidade
Glândula Tireoide/fisiologia
Tiroxina/sangue
Tri-Iodotironina/sangue
[Mh] Termos MeSH secundário: Animais
Geografia
Masculino
Muda/fisiologia
Coelhos
Ratos
Ratos Wistar
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
06LU7C9H1V (Triiodothyronine); Q51BO43MG4 (Thyroxine); W980KJ009P (Corticosterone)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.1007/s10517-017-3720-3


  5 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27774839
[Au] Autor:Jeong HS; Choi EK; Song IU; Chung YA; Park JS; Oh JK
[Ad] Endereço:1 Department of Radiology, Incheon St. Mary's Hospital, The Catholic University of Korea , Incheon, South Korea .
[Ti] Título:Differences in Brain Glucose Metabolism During Preparation for I Ablation in Thyroid Cancer Patients: Thyroid Hormone Withdrawal Versus Recombinant Human Thyrotropin.
[So] Source:Thyroid;27(1):23-28, 2017 Jan.
[Is] ISSN:1557-9077
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: In preparation for I ablation, temporary withdrawal of thyroid hormone is commonly used in patients with thyroid cancer after total thyroidectomy. The current study aimed to investigate brain glucose metabolism and its relationships with mood or cognitive function in these patients using F-fluoro-2-deoxyglucose positron emission tomography ( F-FDG-PET). METHOD: A total of 40 consecutive adult patients with thyroid carcinoma who had undergone total thyroidectomy were recruited for this cross-sectional study. At the time of assessment, 20 patients were hypothyroid after two weeks of thyroid hormone withdrawal, while 20 received thyroid hormone replacement therapy and were euthyroid. All participants underwent brain F-FDG-PET scans and completed mood questionnaires and cognitive tests. Multivariate spatial covariance analysis and univariate voxel-wise analysis were applied for the image data. RESULTS: The hypothyroid patients were more anxious and depressed than the euthyroid participants. The multivariate covariance analysis showed increases in glucose metabolism primarily in the bilateral insula and surrounding areas and concomitant decreases in the parieto-occipital regions in the hypothyroid group. The level of thyrotropin was positively associated with the individual expression of the covariance pattern. The decreased F-FDG uptake in the right cuneus cluster from the univariate analysis was correlated with the increased thyrotropin level and greater depressive symptoms in the hypothyroid group. CONCLUSIONS: These results suggest that temporary hypothyroidism, even for a short period, may induce impairment in glucose metabolism and related affective symptoms.
[Mh] Termos MeSH primário: Encéfalo/metabolismo
Glucose/metabolismo
Neoplasias da Glândula Tireoide/metabolismo
[Mh] Termos MeSH secundário: Adulto
Afeto/fisiologia
Ansiedade/diagnóstico por imagem
Ansiedade/metabolismo
Ansiedade/psicologia
Encéfalo/diagnóstico por imagem
Cognição/fisiologia
Estudos Transversais
Depressão/diagnóstico por imagem
Depressão/metabolismo
Depressão/psicologia
Feminino
Fluordesoxiglucose F18
Seres Humanos
Radioisótopos do Iodo/uso terapêutico
Masculino
Meia-Idade
Tomografia por Emissão de Pósitrons
Neoplasias da Glândula Tireoide/diagnóstico por imagem
Neoplasias da Glândula Tireoide/psicologia
Neoplasias da Glândula Tireoide/radioterapia
Tireoidectomia
Tireotropina/sangue
Tiroxina/sangue
Tri-Iodotironina/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Iodine Radioisotopes); 06LU7C9H1V (Triiodothyronine); 0Z5B2CJX4D (Fluorodeoxyglucose F18); 9002-71-5 (Thyrotropin); IY9XDZ35W2 (Glucose); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE
[do] DOI:10.1089/thy.2016.0293


  6 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29306024
[Au] Autor:Hill KL; Hamers T; Kamstra JH; Willmore WG; Letcher RJ
[Ad] Endereço:Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, Canada; Department of Biology, Carleton University, Ottawa, Canada; Intrinsik Corp., Ottawa, Canada.
[Ti] Título:Organophosphate triesters and selected metabolites enhance binding of thyroxine to human transthyretin in vitro.
[So] Source:Toxicol Lett;285:87-93, 2018 Mar 15.
[Is] ISSN:1879-3169
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The toxicological properties of organophosphate (OP) triesters that are used as flame retardants and plasticizers are currently not well understood, though increasing evidence suggests they can affect the thyroid system. Perturbation of thyroid hormone (TH) transport is one mechanism of action that may affect thyroid function. The present study applied an in vitro competitive protein binding assay with thyroxine (T4) and human transthyretin (hTTR) transport protein to determine the potential for the OP triesters, TDCIPP (tris(1,3-dichloro-2-propyl) phosphate), TBOEP (tris(butoxyethyl) phosphate), TEP (triethyl phosphate), TPHP (triphenyl phosphate), p-OH-TPHP (para-hydroxy triphenyl phosphate), and the OP diester DPHP (diphenyl phosphate), to competitively displace T4 from hTTR. Enhancement of T4 binding to hTTR, rather than the hypothesized competition, was observed for the six OP esters and in a concentration-dependent manner. For example, T4-hTTR binding was significantly increased at concentrations of TBOEP as low as 64 nM, and up to 184% of controls at 5000 nM. A plausible explanation of these results, which to our knowledge has not been previously reported, may be allosteric interactions of the OP esters with hTTR allowing T4 to access the second site of the TH binding pocket. These in vitro results suggest a novel mechanism of OP ester toxicity via T4 binding enhancement, and possible dysregulation of T4-hTTR interactions.
[Mh] Termos MeSH primário: Retardadores de Chama/toxicidade
Organofosfatos/toxicidade
Plastificantes/toxicidade
Pré-Albumina/metabolismo
Tiroxina/metabolismo
[Mh] Termos MeSH secundário: Ligação Competitiva
Ésteres
Retardadores de Chama/metabolismo
Seres Humanos
Organofosfatos/metabolismo
Plastificantes/metabolismo
Ligação Proteica
Glândula Tireoide/efeitos dos fármacos
Glândula Tireoide/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Esters); 0 (Flame Retardants); 0 (Organophosphates); 0 (Plasticizers); 0 (Prealbumin); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180219
[Lr] Data última revisão:
180219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180107
[St] Status:MEDLINE


  7 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28964732
[Au] Autor:Pérez JH; Meddle SL; Wingfield JC; Ramenofsky M
[Ad] Endereço:Department of Neurobiology, Physiology and Behavior, University of California, One Shields Avenue, Davis, CA 95616, USA. Electronic address: jonathan.perez@abdn.ac.uk.
[Ti] Título:Effects of thyroid hormone manipulation on pre-nuptial molt, luteinizing hormone and testicular growth in male white-crowned sparrows (Zonotrichia leuchophrys gambelii).
[So] Source:Gen Comp Endocrinol;255:12-18, 2018 Jan 01.
[Is] ISSN:1095-6840
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Most seasonal species rely on the annual change in day length as the primary cue to appropriately time major spring events such as pre-nuptial molt and breeding. Thyroid hormones are thought to be involved in the regulation of both of these spring life history stages. Here we investigated the effects of chemical inhibition of thyroid hormone production using methimazole, subsequently coupled with either triiodothyronine (T3) or thyroxine (T4) replacement, on the photostimulation of pre-nuptial molt and breeding in Gambel's white-crowned sparrows (Zonotrichia leuchophrys gambelii). Suppression of thyroid hormones completely prevented pre-nuptial molt, while both T3 and T4 treatment restored normal patterns of molt in thyroid hormone-suppressed birds. Testicular recrudescence was blocked by methimazole, and restored by T4 but not T3, in contrast to previous findings demonstrating central action of T3 in the photostimulation of breeding. Methimazole and replacement treatments elevated plasma luteinizing hormone levels compared to controls. These data are partially consistent with existing theories on the role of thyroid hormones in the photostimulation of breeding, while highlighting the possibility of additional feedback pathways. Thus we suggest that regulation of the hypothalamic pituitary gonad axis that controls breeding may be more complex than previously considered.
[Mh] Termos MeSH primário: Hormônio Luteinizante/sangue
Muda/efeitos dos fármacos
Pardais/sangue
Pardais/crescimento & desenvolvimento
Testículo/crescimento & desenvolvimento
Hormônios Tireóideos/farmacologia
[Mh] Termos MeSH secundário: Animais
Masculino
Pardais/fisiologia
Testículo/anatomia & histologia
Testículo/efeitos dos fármacos
Tiroxina/sangue
Tri-Iodotironina/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Thyroid Hormones); 06LU7C9H1V (Triiodothyronine); 9002-67-9 (Luteinizing Hormone); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171002
[St] Status:MEDLINE


  8 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29304184
[Au] Autor:Seara FAC; Maciel L; Barbosa RAQ; Rodrigues NC; Silveira ALB; Marassi MP; Carvalho AB; Nascimento JHM; Olivares EL
[Ad] Endereço:Laboratory of Cardiovascular Physiology and Pharmacology, Department of Physiological Sciences, Institute of Biology, Federal Rural University of Rio de Janeiro, Seropedica-RJ, Brazil.
[Ti] Título:Cardiac ischemia/reperfusion injury is inversely affected by thyroid hormones excess or deficiency in male Wistar rats.
[So] Source:PLoS One;13(1):e0190355, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:AIM: Thyroid dysfunctions can increase the risk of myocardial ischemia and infarction. However, the repercussions on cardiac ischemia/reperfusion (IR) injury remain unclear so far. We report here the effects of hypothyroidism and thyrotoxicosis in the susceptibility to IR injury in isolated rat hearts compared to euthyroid condition and the potential role of antioxidant enzymes. METHODS: Hypothyroidism and thyrotoxicosis were induced by administration of methimazole (MMZ, 300 mg/L) and thyroxine (T4, 12 mg/L), respectively in drinking water for 35 days. Isolated hearts were submitted to IR and evaluated for mechanical dysfunctions and infarct size. Superoxide dismutase types 1 and 2 (SOD1 and SOD2), glutathione peroxidase types 1 and 3 (GPX 1 and GPX3) and catalase mRNA levels were assessed by quantitative RT-PCR to investigate the potential role of antioxidant enzymes. RESULTS: Thyrotoxicosis elicited cardiac hypertrophy and increased baseline mechanical performance, including increased left ventricle (LV) systolic pressure, LV developed pressure and derivatives of pressure (dP/dt), whereas in hypothyroid hearts exhibited decreased dP/dt. Post-ischemic recovery of LV end-diastolic pressure (LVEDP), LVDP and dP/dt was impaired in thyrotoxic rat hearts, whereas hypothyroid hearts exhibited improved LVEDP and decreased infarct size. Catalase expression was decreased by thyrotoxicosis. CONCLUSION: Thyrotoxicosis was correlated, at least in part, to cardiac remodeling and increased susceptibility to IR injury possibly due to down-regulation of antioxidant enzymes, whereas hypothyroid hearts were less vulnerable to IR injury.
[Mh] Termos MeSH primário: Traumatismo por Reperfusão Miocárdica/sangue
Traumatismo por Reperfusão Miocárdica/patologia
Tiroxina/sangue
Tri-Iodotironina/sangue
[Mh] Termos MeSH secundário: Animais
Masculino
Ratos
Ratos Wistar
Reação em Cadeia da Polimerase Via Transcriptase Reversa
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
06LU7C9H1V (Triiodothyronine); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180106
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190355


  9 / 32265 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29017816
[Au] Autor:Chang J; Wang H; Xu P; Guo B; Li J; Wang Y; Li W
[Ad] Endereço:Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing RD 18, Beijing, 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing, 100049, China.
[Ti] Título:Oral and dermal diflubenzuron exposure causes a hypothalamic-pituitary-thyroid (HPT) axis disturbance in the Mongolian racerunner (Eremias argus).
[So] Source:Environ Pollut;232:338-346, 2018 Jan.
[Is] ISSN:1873-6424
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Diflubenzuron (DFB) is a potential endocrine-disrupting chemical. However, its thyroid endocrine effect on reptiles has not been reported. In this study, immature lizards (Eremias argus) were exposed to 20 mg kg DFB once a week for 42 days through oral or dermal routes. Their body weight, plasma thyroid hormone levels, thyroid gland histology and the transcription of hypothalamic-pituitary-thyroid (HPT) axis-related genes in different tissues were assessed to explore the effects of DFB on the HPT axis of lizards. The body weight decreased significantly only after the dermal exposure to DFB. Triiodothyronine (T3) to thyroxine (T4) ratio in the male plasma also significantly increased after the dermal exposure. After oral exposure, the activity of thyroid gland was positively related to the thyroid hormone levels. Furthermore, the alterations in thyroid hormone levels affected the HPT axis-related gene expression, which was tissue dependent and sexually selected. The thyroid hormone receptor genes (trα and trß) in the brain and thyroid were more sensitive to oral exposure. However, only the dermal treatment affected the trα, trß and type 2 deiodinase (dio2) genes in the male liver. These results suggest that DFB exposure caused sex-specific changes in the thyroid function of lizards, and the dermal treatment may be an important route for the risk assessment of reptiles.
[Mh] Termos MeSH primário: Diflubenzuron/toxicidade
Disruptores Endócrinos/toxicidade
Hormônios Juvenis/toxicidade
Lagartos/fisiologia
[Mh] Termos MeSH secundário: Animais
Disruptores Endócrinos/metabolismo
Hipotálamo/efeitos dos fármacos
Lagartos/metabolismo
Masculino
Hipófise/efeitos dos fármacos
Glândula Tireoide/metabolismo
Hormônios Tireóideos/metabolismo
Tiroxina/sangue
Testes de Toxicidade
Tri-Iodotironina/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Endocrine Disruptors); 0 (Juvenile Hormones); 0 (Thyroid Hormones); 06LU7C9H1V (Triiodothyronine); J76U6ZSI8D (Diflubenzuron); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180122
[Lr] Data última revisão:
180122
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171012
[St] Status:MEDLINE


  10 / 32265 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28970022
[Au] Autor:Chang J; Hao W; Xu Y; Xu P; Li W; Li J; Wang H
[Ad] Endereço:Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Shuangqing RD 18, Beijing 100085, China; University of Chinese Academy of Sciences, Yuquan RD 19 a, Beijing 100049, China.
[Ti] Título:Stereoselective degradation and thyroid endocrine disruption of lambda-cyhalothrin in lizards (Eremias argus) following oral exposure.
[So] Source:Environ Pollut;232:300-309, 2018 Jan.
[Is] ISSN:1873-6424
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The disturbance of the thyroid system and elimination of chiral pyrethroid pesticides with respect to enantioselectivity in reptiles have so far received limited attention by research. In this study, bioaccumulation, thyroid gland lesions, thyroid hormone levels, and hypothalamus-pituitary-thyroid axis-related gene expression in male Eremias argus were investigated after three weeks oral administration of lambda-cyhalothrin (LCT) enantiomers. In the lizard liver, the concentration of LCT was negatively correlated with the metabolite-3-phenoxybenzoic acid (PBA) level during 21 days of exposure. (+)-LCT exposure induced a higher thyroid follicular epithelium height than (-)-LCT exposure. The thyroxine levels were increased in both treated groups while only (+)-LCT exposure induced a significant change in the triiodothyronine (T3) level. In addition, the expressions of hypothalamus-pituitary-thyroid axis-related genes including thyroid hormone receptors (trs), deiodinases (dios), uridinediphosphate glucuronosyltransferase (udp), and sulfotransferase (sult) were up-regulated after exposure to the two enantiomers. (+)-LCT treatment resulted in higher expression of trs and (-)-LCT exposure led to greater stimulation of dios in the liver, which indicated PBA-induced antagonism on thyroid hormone receptors and LCT-induced disruption of thyroxine (T4) deiodination. The results suggest the (-)-LCT exposure causes higher residual level in lizard liver while induces less disruption on lizard thyroid activity than (+)-LCT.
[Mh] Termos MeSH primário: Lagartos/fisiologia
Nitrilos/toxicidade
Praguicidas/toxicidade
Piretrinas/toxicidade
Glândula Tireoide/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Benzoatos
Disruptores Endócrinos/metabolismo
Iodeto Peroxidase/metabolismo
Fígado/metabolismo
Lagartos/metabolismo
Masculino
Praguicidas/metabolismo
Receptores dos Hormônios Tireóideos/metabolismo
Estereoisomerismo
Glândula Tireoide/metabolismo
Hormônios Tireóideos/metabolismo
Tiroxina
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Benzoates); 0 (Endocrine Disruptors); 0 (Nitriles); 0 (Pesticides); 0 (Pyrethrins); 0 (Receptors, Thyroid Hormone); 0 (Thyroid Hormones); 69DC2655VH (3-phenoxybenzoic acid); EC 1.11.1.8 (Iodide Peroxidase); Q51BO43MG4 (Thyroxine); V0V73PEB8M (cyhalothrin)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180122
[Lr] Data última revisão:
180122
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE



página 1 de 3227 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde