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1.
J Endocrinol Invest ; 43(12): 1717-1722, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32474767

RESUMO

PURPOSE: Patients with Graves' orbitopathy can present with asymmetric disease. The aim of this study was to identify clinical characteristics that distinguish asymmetric from unilateral and symmetric Graves' orbitopathy. METHODS: This was a multi-centre study of new referrals to 13 European Group on Graves' Orbitopathy (EUGOGO) tertiary centres. New patients presenting over a 4 month period with a diagnosis of Graves' orbitopathy were included. Patient demographics were collected and a clinical examination was performed based on a previously published protocol. Patients were categorized as having asymmetric, symmetric, and unilateral Graves' orbitopathy. The distribution of clinical characteristics among the three groups was documented. RESULTS: The asymmetric group (n = 83), was older than the symmetric (n = 157) group [mean age 50.9 years (SD 13.9) vs 45.8 (SD 13.5), p = 0.019], had a lower female to male ratio than the symmetric and unilateral (n = 29) groups (1.6 vs 5.0 vs 8.7, p < 0.001), had more active disease than the symmetric and unilateral groups [mean linical Activity Score 3.0 (SD 1.6) vs 1.7 (SD 1.7), p < 0.001 vs 1.3 (SD 1.4), p < 0.001] and significantly more severe disease than the symmetric and unilateral groups, as measured by the Total Eye Score [mean 8.8 (SD 6.6) vs 5.3 (SD 4.4), p < 0.001, vs 2.7 (SD 2.1), p < 0.001]. CONCLUSION: Older age, lower female to male ratio, more severe, and more active disease cluster around asymmetric Graves' orbitopathy. Asymmetry appears to be a marker of more severe and more active disease than other presentations. This simple clinical parameter present at first presentation to tertiary centres may be valuable to clinicians who manage such patients.


Assuntos
Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/patologia , Adulto , Idoso , Estudos Transversais , Progressão da Doença , Assimetria Facial/diagnóstico , Assimetria Facial/etiologia , Feminino , Oftalmopatia de Graves/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença
2.
Rev Epidemiol Sante Publique ; 65(4): 301-308, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28579185

RESUMO

BACKGROUND: In retrospective case-control studies performed following nuclear tests or nuclear accidents, individual thyroid radiation dose reconstructions are based on fallout and meteorological data from the residential area, demographic characteristics, and lifestyle as well as dietary information. Collecting the latter is a controversial step, as dietary declarations may be affected by the subjects' beliefs about their risk behavior. This report analyses the potential for such bias in a case-control study performed in eastern France. METHODS: The study included 765 cases of differentiated thyroid carcinoma matched with 831 controls. Risk perceptions and beliefs of cases and controls were compared using Chi2 tests and differences in dietary reports were analyzed using a two-way ANOVA. RESULTS: In general, atmospheric pollution and living near a nuclear power plant were the two major risks that may influence thyroid cancer occurrence cited by cases and controls. When focusing in particular on the consequences of the Chernobyl accident, cases were more likely to think that the consequences were responsible for thyroid cancer occurrence than controls. Vegetable consumption during the two months after the Chernobyl accident was correlated with the status of subjects, but not to their beliefs. Conversely, consumption of fresh dairy products was not correlated with the status or beliefs of subjects. CONCLUSION: We found no evidence of systematic bias in dietary reports according to the status or beliefs held by subjects about the link between thyroid cancer occurrence and Chernobyl fallout. As such, these dietary reports may be used in further studies involving individual dosimetric reconstructions.


Assuntos
Acidente Nuclear de Chernobyl , Registros de Dieta , Comportamento Alimentar/psicologia , Contaminação Radioativa de Alimentos , Percepção , Cinza Radioativa , Neoplasias da Glândula Tireoide/epidemiologia , Adolescente , Adulto , Viés , Estudos de Casos e Controles , Criança , Desastres , Feminino , França/epidemiologia , Humanos , Masculino , Centrais Nucleares , Inquéritos Nutricionais , Cinza Radioativa/análise , Cinza Radioativa/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Comportamento de Redução do Risco , Adulto Jovem
3.
Nat Genet ; 7(3): 396-401, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7920658

RESUMO

The thyrotropin receptor (TSHR), a member of the large family of G protein-coupled receptors, controls both the function and growth of thyroid cells via stimulation of adenylyl cyclase. We report two different mutations in the TSHR gene of affected members of two large pedigrees with non-autoimmune autosomal dominant hyperthyroidism (toxic thyroid hyperplasia), that involve residues in the third (Val509Ala) and seventh (Cys672Tyr) transmembrane segments. When expressed by transfection in COS-7 cells, the mutated receptors display a higher constitutive activation of adenylyl cyclase than wild type. This new disease entity is the germline counterpart of hyperfunctioning thyroid adenomas, in which different somatic mutations with similar functional characteristics have been demonstrated.


Assuntos
Genes Dominantes , Hipertireoidismo/genética , Mutação Puntual , Receptores da Tireotropina/genética , Adenoma/genética , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , AMP Cíclico/fisiologia , Análise Mutacional de DNA , Ativação Enzimática , Feminino , França/epidemiologia , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Receptores da Tireotropina/química , Receptores da Tireotropina/fisiologia , Sistemas do Segundo Mensageiro , Neoplasias da Glândula Tireoide/genética , Transfecção
5.
Nat Commun ; 9(1): 2298, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880814

RESUMO

The original PDF and HTML versions of this Article omitted the ORCID ID of the authors L. Magazzù and P. Forn-Díaz. (L. Magazzù: 0000-0002-4377-8387; P. Forn-Diaz: 0000-0003-4365-5157).The original PDF version of this Article contained errors in Eqs. (2), (6), (13), (14), (25), (26). These equations were missing all instances of 'Γ' and 'Δ', which are correctly displayed in the HTML version.Similarly, the inline equation in the third sentence of the caption of Fig. 2 was missing the left hand term 'Ω'.The original HTML version of this Article contained errors in Table 1. The correct version of the sixth row of the first column states 'Figure 2' instead of the original, incorrect 'Figure'. And the correction version of the ninth row of the first column states 'Figure 3' instead of the original, incorrect 'Figure'.This has been corrected in both the PDF and HTML versions of the Article.

6.
Nat Commun ; 9(1): 1403, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643365

RESUMO

Quantum two-level systems interacting with the surroundings are ubiquitous in nature. The interaction suppresses quantum coherence and forces the system towards a steady state. Such dissipative processes are captured by the paradigmatic spin-boson model, describing a two-state particle, the "spin", interacting with an environment formed by harmonic oscillators. A fundamental question to date is to what extent intense coherent driving impacts a strongly dissipative system. Here we investigate experimentally and theoretically a superconducting qubit strongly coupled to an electromagnetic environment and subjected to a coherent drive. This setup realizes the driven Ohmic spin-boson model. We show that the drive reinforces environmental suppression of quantum coherence, and that a coherent-to-incoherent transition can be achieved by tuning the drive amplitude. An out-of-equilibrium detailed balance relation is demonstrated. These results advance fundamental understanding of open quantum systems and bear potential for the design of entangled light-matter states.

7.
Eur J Endocrinol ; 157(1): 53-61, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17609402

RESUMO

OBJECTIVE: Diabetes is clinically classified into two types: type 1 (T1D) and type 2 diabetes (T2D). Nevertheless, intermediate forms of diabetes are frequent and difficult to recognize and manage appropriately. In this study, we investigated whether patients with intermediate form of diabetes, here called unclassified diabetes (UD), have beta-cell autoimmune markers. RESEARCH DESIGN AND METHODS: beta-cell autoimmune markers (beta-cell autoantibodies (aAb), peripheral blood mononuclear cells (PBMC) responsive to five islet proteins, cytokine secretion, and human leukocyte antigen (HLA)-DQB1 genotypes) were analyzed in 50 UD patients, 23 age- and HLA-matched normal control subjects, and 23 classic T2D patients. RESULTS: We observed that 16 out of 50 (32%) UD patients demonstrated responsive PBMCs, as opposed to 1 out of 23 (5%) age- and HLA-matched normal control subjects, and 0 out of 23 classic T2D patients. Overall, 29 (58%) UD patients had at least one marker of beta-cell autoimmunity (beta-cell aAb and/or PBMC autoreactivity), in association with high-risk HLA genotypes DQB1*0201 and/or DQB1*0302. Moreover, the 13 (26%) UD patients who had beta-cell aAb were not the same as those with PBMC autoreactivity, except for one patient. Patients with PBMC autoreactivity were older at the onset of the disease and had a better residual beta-cell function than those with beta-cell aAb. CONCLUSIONS: Our data confirm that T-cell autoimmunity can be detected in latent autoimmune diabetes in adults patients. We show an inverse correlation between humoral and cellular beta-cell autoimmunities. Possible protective cellular responses in the patients with beta-cell PBMC autoreactivity could have potential therapeutic implications.


Assuntos
Formação de Anticorpos/fisiologia , Autoimunidade/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Imunidade Celular/fisiologia , Adulto , Idoso , Autoanticorpos/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/imunologia , Progressão da Doença , Feminino , Humanos , Células Secretoras de Insulina/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
8.
Eur J Endocrinol ; 154(5): 633-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16645008

RESUMO

Mild forms of hypothyroidism--subclinical hypothyroidism--have recently been discussed as being a risk factor for the development of overt thyroid dysfunction and for a number of clinical disorders. The diagnosis critically depends on the definition of the upper normal limit of serum TSH as, by definition, free thyroxine serum concentrations are normal. Cut-off levels of 4-5 mU TSH/l have been conventionally used to diagnose an elevated TSH serum concentration. Recent data from large population studies have suggested a much lower TSH cut-off with an upper limit of 2-2.5 mU/l but application of strict criteria for inclusion of subjects from the general population studies aiming at assessing TSH reference intervals (no personal or family history of thyroid disease, no thyroid antibodies and a normal thyroid on ultrasonography) did not result in an unequivocal upper limit of normal TSH at 2.0-2.5 mU/l. When summarizing the available evidence for lowered upper TSH cut-off values and their potential therapeutic implications there is presently insufficient justification to lower the upper normal limit of TSH and, for practical purposes, it is still recommended to maintain the TSH reference interval of 0.4-4.0 mU/l. Classifying subjects with a TSH value between 2 and 4 mU/l as abnormal, as well as intervening with thyroxine treatment in such subjects, is probably doing more harm than good.


Assuntos
Química Clínica/normas , Doenças da Glândula Tireoide/sangue , Doenças da Glândula Tireoide/diagnóstico , Tireotropina/análise , Tireotropina/sangue , Humanos , Valores de Referência
9.
Eur J Endocrinol ; 155(2): 207-11, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16868132

RESUMO

OBJECTIVE: To determine management patterns among clinicians who treat patients with Graves' orbitopathy (GO) in Europe. DESIGN AND METHODS: Questionnaire survey including a case scenario of members of professional organisations representing endocrinologists, ophthalmologists and nuclear medicine physicians. RESULTS: A multidisciplinary approach to manage GO was valued by 96.3% of responders, although 31.5% did not participate or refer to a multidisciplinary team and 21.5% of patients with GO treated by responders were not managed in a multidisciplinary setting. Access to surgery for sight-threatening GO was available only within weeks or months according to 59.5% of responders. Reluctance to refer urgently to an ophthalmologist was noted by 32.7% of responders despite the presence of suspected optic neuropathy. The use of steroids was not influenced by the age of the patient, but fewer responders chose to use steroids in a diabetic patient (72.1 vs 90.5%, P<0.001). Development of cushingoid features resulted in a reduction in steroid use (90.5 vs 36.5%, P<0.001) and increase in the use of orbital irradiation (from 23.8% to 40.4%, P<0.05) and surgical decompression (from 20.9 to 52.9%, P<0.001). More ophthalmologists chose surgical decompression for patients with threatened vision due to optic neuropathy, who were intolerant to steroids than other specialists (70.3 vs 41.8%, P<0.01). CONCLUSION: Deficiencies in the management of patients with GO in Europe were identified by this survey. Further training of clinicians, easier access of patients to specialist multidisciplinary centres and the publication of practice guidelines may help improve the management of this condition in Europe.


Assuntos
Endocrinologia/estatística & dados numéricos , Oftalmopatia de Graves/cirurgia , Oftalmopatia de Graves/terapia , Pesquisas sobre Atenção à Saúde , Descompressão Cirúrgica , Europa (Continente) , Oftalmopatia de Graves/diagnóstico , Acessibilidade aos Serviços de Saúde , Humanos , Radioisótopos do Iodo/uso terapêutico , Órbita , Equipe de Assistência ao Paciente/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta/estatística & dados numéricos , Esteroides/uso terapêutico , Inquéritos e Questionários , Tireoidectomia/estatística & dados numéricos
10.
Ann Endocrinol (Paris) ; 67(4): 281-6, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-17072231

RESUMO

Iodine intake varies with age and physiological status: in pregnant and lactating women, recommended iodine intake ranges from 200 to 250 mg/day. Recent epidemiological studies in France demonstrate the presence of moderate iodine deficiency in the majority of pregnant and lactating women. This iodine deficiency induces maternal thyroid hyperplasia and then development of goiter in women, as well as impaired thyroid parameters. Maternal hypothyroxinemia during the first trimester of pregnancy can be associated with abnormal cognitive development and intellectual outcomes in the newborn and the children. According to the recent World Health Organization recommendations for the prevention and control of iodine deficiency in pregnant and lactating women, systematic iodine supplementation is indicated in France: 100 microg/day for women of reproductive age and 200 microg/day in pregnant and lactating women in order to eradicate iodine deficiency during pregnancy and lactation, and prevent the maternal and fetal consequences.


Assuntos
Iodo/deficiência , Iodo/uso terapêutico , Lactação , Complicações na Gravidez/prevenção & controle , Feminino , França , Humanos , Iodo/farmacocinética , Gravidez , Complicações na Gravidez/tratamento farmacológico , Fenômenos Fisiológicos da Nutrição Pré-Natal , Doenças da Glândula Tireoide/tratamento farmacológico
11.
Med Mal Infect ; 36(4): 219-22, 2006 Apr.
Artigo em Francês | MEDLINE | ID: mdl-16580164

RESUMO

OBJECTIVES AND METHOD: The discordance between test by urine dipstick (nitrites and leucocyte-esterase) and analysis in laboratory, with urinary culture on the same sample was studied in diabetic patients, from October 2000 to May 2002, to eventually stop systematic laboratory test. The dipstick result (Clinitek 20 Bayer) was classified as "possibility of bacteriuria" if one of the two tests was positive. Bacteriuria was considered significant if the laboratory test result gave, at least 10(5) bacteria per mL, (one strain), and at least 10(4) leucocytes. The out point was the dipstick negative predictive value (NPV). RESULTS: The study included 683 patients. The dipstick result was "possibility of bacteriuria" in 153 cases (22.4%). Thirty-nine bacteriuria (5.7%) were reported, including 2 dipstick false negatives. The NPV was 99.6% [IC 95% : 99.1-100]. CONCLUSION: The systematic laboratory tests were stopped.


Assuntos
Bacteriúria/diagnóstico , Complicações do Diabetes/diagnóstico , Testes Diagnósticos de Rotina , Procedimentos Desnecessários , Urina/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriúria/epidemiologia , Bacteriúria/etiologia , Bacteriúria/urina , Criança , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/urina , Testes Diagnósticos de Rotina/estatística & dados numéricos , Suscetibilidade a Doenças , Reações Falso-Negativas , Feminino , França/epidemiologia , Glicosúria/epidemiologia , Hematúria/epidemiologia , Humanos , Corpos Cetônicos/urina , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Proteinúria/epidemiologia , Fitas Reagentes , Procedimentos Desnecessários/estatística & dados numéricos , Urina/citologia
12.
Biochim Biophys Acta ; 1051(1): 1-5, 1990 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-2297535

RESUMO

Thyrocytes, which are functional cells of human thyroid, have been isolated, and their glycosphingolipid content has been analyzed in the various fractions obtained from the digested gland as well as in the tissue remaining after enzymatic treatment. The ganglioside content was not significantly different in the different fractions, with GM3 and Gd3 as major components. Analysis of neutral glycolipids revealed striking differences between isolated thyrocytes and whole thyroid. The membraneous material released from the proteinase-treated thyroid presented a pattern of monohexosylceramides clearly distinct from that of thyrocytes. The present data suggest the presence of at least two cellular populations with distinct glycolipid patterns in thyroid tissue: accessory cells containing most of the glycolipids, and thyrocytes in which the major neutral glycosphingolipid is phytosphingosine-containing glucosylceramide.


Assuntos
Glicoesfingolipídeos/metabolismo , Glândula Tireoide/metabolismo , Cromatografia em Camada Fina , Gangliosídeos/análise , Humanos , Glândula Tireoide/citologia , Glândula Tireoide/ultraestrutura
13.
J Clin Endocrinol Metab ; 90(2): 841-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15562016

RESUMO

There are few effective, safe modalities for the management of Graves' ophthalmopathy (GO), a cell-mediated immune comorbidity of thyroid disease. Somatostatin analogs inhibit lymphocyte proliferation and activation, and accumulate in the orbital tissue of patients with GO. A double-blind, placebo-controlled study of a long-acting somatostatin analog [16 wk of long-acting release formulation of octreotide (octreotide-LAR)] was conducted in 51 patients with mild active GO with the aim of preventing deterioration and precluding the need for more aggressive therapeutic modalities, such as glucocorticoids or radiotherapy. No treatment effect was observed for the primary end point (a composite parameter defining the outcome as either success or failure on the basis of changes in class/grade of the severity index and Clinical Activity Scale of GO). The Clinical Activity Scale score was reduced for patients treated with octreotide-LAR, but without any significant difference with respect to patients receiving placebo. However, octreotide-LAR significantly reduced proptosis (as measured by exophthalmometry). This was associated with nonsignificant differences in favor of octreotide-LAR in a series of proptosis-related parameters: class III grade, opening of the upper eyelid, the difference in ocular pressure between primary position and upgaze, and extraocular muscle involvement. By magnetic resonance imaging evaluation the extraocular muscle volumes appeared reduced, but nonsignificantly. No significant correlation between the initial uptake of the somatostatin analog indium-labeled and the response to treatment was observed. One patient in the octreotide-LAR group developed gallstones. In this study, octreotide-LAR did not seem suitable to mitigate activity in mild GO. Surprisingly, it significantly reduced proptosis, one of the most debilitating symptoms of GO. Additional studies are warranted to define the benefit to risk ratio of the somatostatin analogs in this indication.


Assuntos
Doença de Graves/tratamento farmacológico , Octreotida/uso terapêutico , Preparações de Ação Retardada , Demografia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Octreotida/administração & dosagem , Placebos , Fatores de Tempo
14.
Diabetes ; 45(9): 1181-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8772719

RESUMO

The involvement of adhesion molecule in the process of T-cell homing to the pancreas was investigated in the model of the T-cell transfer of type I diabetes in NOD mice. Treatment of mice using monoclonal anti-lymphocyte function associated antigen (LFA)-1, anti-integrin alpha 4, anti-intercellular adhesion molecule (ICAM)-1, and anti-L-selectin antibodies (monoclonal antibodies [mAbs]) gave rise to a partial or complete prevention of diabetes via different mechanisms of protection. On day 20 posttransfer, diabetes was only observed in control mice (26 of 32) and in few mice treated with the anti-L-selectin mAbs (3 of 24). On day 60, the best protection was observed using the anti-LFA-1 or the anti-integrin alpha 4 mAbs with 3 of 11 and 2 of 5 diabetic mice, respectively. On day 20, no insulitis was observed in the pancreases of mice treated with these mAbs compared with the pancreases of controls, suggesting that such treatment blocked the penetration of T-cells into the islets. In vitro adhesion assays confirmed that adhesion of T-cells to the pancreatic endothelium was blocked, except when using the anti-L-selectin mAb, which induced a modification of the traffic of the transferred T-cells; the ability of T-cells to migrate into the pancreatic lymph nodes was significantly reduced (10.4 vs. 22%). Anti-LFA-1 mAbs did not modify such T-cell trafficking. The present study, therefore, elucidates the role of LFA-1, integrin alpha 4, and L-selectin in T-cell homing to the pancreas, first step of the cascade of events leading to type I diabetes.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD/imunologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Imunoterapia Adotiva , Selectina L/imunologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Transfusão de Linfócitos , Pâncreas/imunologia , Linfócitos T/imunologia , Animais , Adesão Celular , Diabetes Mellitus Tipo 1/patologia , Citometria de Fluxo , Imuno-Histoquímica , Imunofenotipagem , Integrina alfa4 , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos NOD , Modelos Imunológicos , Pâncreas/patologia
15.
Mol Endocrinol ; 2(7): 613-8, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2457799

RESUMO

In order to locate the domains involved in the biological activity of TSH and to get some insight in the relationship between immunological and biological properties of TSH, 24 monoclonal antibodies (mAb) to 11 different antigenic regions of hTSH were tested for both binding to hTSH and inhibition of hTSH stimulation of adenylate cyclase in human thyroid membranes. These mAb were also investigated for binding to bovine TSH (bTSH), and interference with bTSH binding to the receptor and stimulation of adenylate cyclase. Radioiodinated human TSH (hTSH) was incubated with increasing concentrations of mAb. Maximum hTSH binding by the various mAb ranged from 15-75% and was not related to the apparent affinity of the mAb for hTSH. Maximum inhibition by the mAb of hTSH stimulation of adenylate cyclase ranged from 3-92%. As compared to the antigenic map of hTSH, it was observed that mAb reacting with the same antigenic regions might display varying inhibition of hTSH. Nevertheless, it was clearly shown that the most potent inhibitors of hTSH stimulatory activity interacted with epitopes located on the alpha- and beta-subunits or expressed only by holo hTSH. Only 11 of the 24 mAb cross-reacted significantly with bTSH. Seven exhibited the same inhibition of hTSH and bTSH stimulatory activity; the four remaining mAb rather than to inhibit adenylate cyclase stimulation as observed with hTSH, did not interfere or even increased adenylate cyclase stimulation by bTSH.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Monoclonais , Tireotropina/imunologia , Adenilil Ciclases/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Bovinos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Fenômenos Químicos , Química , AMP Cíclico/biossíntese , Epitopos/análise , Humanos , Receptores da Tireotropina/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/ultraestrutura , Tireotropina/metabolismo , Tireotropina/farmacologia
16.
Endocrinology ; 100(6): 1628-35, 1977 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-192541

RESUMO

Perchlorate treatment of mice increased by 1.5-2-fold the thyroid secretory response to TSH, hCG and LATS, in the McKenzie bioassay. Perchlorate alone did not increase basal plasma radioactivity. Perchlorate augmentation of the secretory response index was roughly proportional to the level of stimulation; it was similar for all three stimulators despite their different time courses of action which were unaltered by perchlorate; it was the same whether perchlorate administration preceded, coincided with or shortly followed injection of the stimulator, a finding in keeping with the slow clearance of this ion. The perchlorate effect was dose-related, although within a narrow range (6.25-12.5 microng/mouse). Near-maximal per chlorate effect was obtained with a dose (12.5 microng) which, when tested in different experimental conditions (MMI-blocked thyroid), discharged 80% of intrathyroidal radioiodide. Perchlorate exerted its augmenting effect by enhancing thyroid secretion: it increased plasma radioiodothyronines and radioiodide concentrations without decreaseing the blood disappearance rates of iodide and iodothyronines. The potentiating effect of perchlorate probably takes place at a step prior to cyclic AMP action since it did not affect dbcAMP-stimulated secretion. The perchlorate effect may be indirect, through mobilization of minute amounts of intrathyroidal iodide.


Assuntos
Gonadotropina Coriônica/farmacologia , Estimulador Tireóideo de Ação Prolongada/farmacologia , Percloratos/farmacologia , Glândula Tireoide/efeitos dos fármacos , Tireotropina/farmacologia , Animais , Bucladesina/farmacologia , Relação Dose-Resposta a Droga , Radioisótopos do Iodo , Metimazol/farmacologia , Camundongos , Estimulação Química , Tiocianatos/farmacologia , Glândula Tireoide/metabolismo , Fatores de Tempo
17.
Endocrinology ; 123(4): 2062-6, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3416826

RESUMO

Stimulating anti-TSH receptor antibodies (TSAb) mimic TSH in the induction of refractoriness in cultured thyroid cells; TSAb and TSH desensitize one another. We investigated whether blocking anti-TSH receptor antibodies (TBkAb) have the same desensitizing effects in cultured human thyroid cells. Prolonged exposure of cells (20 h) to TBkAb followed by antigen-antibody dissociation by an acid wash step was required to induce refractoriness to subsequent stimulation of cAMP accumulation with TSH and TSAb. Cycloheximide prevented this desensitization effect. The cAMP response to forskolin was not reduced in cells pretreated by TBkAb and was increased in cells desensitized by TSH or TSAb. The pattern of the TSH dose-response curves suggested that desensitization by TSH or TSAb involved only a postreceptor mechanism but both receptor and postreceptor phenomena in the case of TBkAb. In conclusion, like TSH or TSAb, TBkAb may induce a homologous desensitization in human thyroid cells which is not mediated by cAMP.


Assuntos
Autoanticorpos/imunologia , Receptores da Tireotropina/imunologia , Glândula Tireoide/imunologia , Animais , Ligação Competitiva , Membrana Celular/metabolismo , Células Cultivadas , Colforsina/farmacologia , Feminino , Humanos , Cinética , Receptores da Tireotropina/metabolismo , Suínos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Tireoidite Autoimune/imunologia
18.
Endocrinology ; 107(4): 1245-8, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7408771

RESUMO

We previously observed that under a 12-h light, 12-h dark schedule (lights off at 1900 h), male Sprague-Dawley rats showed a circadian rhythm for serum TSH with a zenith near midday. In the present work we further characterized the serum TSH rhythm by appropriate mathematical analysis. The peak of serum TSH occurred at 1130 +/- 0105 h (mean of five experiments), with an amplitude of 0.2 +/- 0.1 microgram/ml, while the TSH level was minimum at the beginning of the dark period; the period of the TSH rhythm was 24.5 +/- 0.6 h. A circadian rhythm was also demonstrated for serum T3 and T4; these rhythms were characterized by peaks occurring 1.5 and 2.2 h after that of TSH, respectively. As expected, characteristics of the rhythm were more narrowly defined for T3 than for T4. Serum concentrations peaked at 1256 +/- 0206 and 1346 +/- 0308 h for T3 and T4, respectively; the serum T3 concentration varied from 78.7 +/- 7.8 to 54.2 +/- 2.7 ng/100 ml (P < 0.001) and serum T4 varied from 7.3 +/- 1.1 to 5.1 +/- 0.5 microgram/100 ml (P < 0.05) for zenith and nadir values, respectively. It is suggested that the diurnal peaks of thyroid hormones might be related to TSH-induced changes in thyroid secretion.


Assuntos
Ritmo Circadiano , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Animais , Escuridão , Luz , Masculino , Ratos
19.
J Clin Endocrinol Metab ; 84(7): 2419-24, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10404814

RESUMO

Antigenic proliferative responses of peripheral blood mononuclear cells (PBMC) to insulin were studied in 44 type 1 new-onset diabetic subjects. Of them, 14 (32%) had a stimulation index (> or =3) above the mean + 3 SD of 39 healthy controls and of 7 of 15 (47%) diabetic patients of long duration (P = 0.001). Responses to insulin were not dictated by specific major histocompatibility complex class II association and were not observed in normal subjects with diabetes-associated human leukocyte antigen-DR/DQ alleles. Whereas no relation of PBMC reactivity with insulin autoantibodies was found, there was a positive correlation with the presence of at least one of the four autoantibodies tested and with IA-2 antibody. An interesting finding was that the proportion of patients with subsequent low insulin requirement, up to 24 months, was significantly higher in patients who showed PBMC reactivity to insulin (8 of 8) than in those who did not (10 of 24, 42%; P = 0.004). The former had a higher mean stimulation index than the latter (3.3+/-2.6 vs. 1.5+/-0.6; P = 0.006). Furthermore, interleukin-4 (IL-4) production was lower in type 1 diabetic patients who proliferated to insulin than in those who did not (23+/-15 vs. 64+/-47 pg/mL; P = 0.04), but interferon-gamma, IL-2, and IL-10 productions were similar. In conclusion, these results suggest that proliferation to insulin may reflect the presence of an higher residual beta-cell mass.


Assuntos
Citocinas/biossíntese , Diabetes Mellitus Tipo 1/sangue , Insulina/farmacologia , Indução de Remissão , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Adolescente , Adulto , Autoanticorpos/sangue , Células Cultivadas , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Feminino , Antígeno HLA-DR3/análise , Antígeno HLA-DR4/análise , Humanos , Insulina/administração & dosagem , Insulina/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Masculino
20.
J Clin Endocrinol Metab ; 47(2): 428-34, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-263306

RESUMO

Virilization may occur during pregnancy as the result of an ovarian Krukenberg tumor. mechanism of the androgen overproduction in this exceptional condition is still poorly understood. A new case is reported in which only in the postpartum clinical, endocrine, and endoscopic studies led to the diagnosis of an ovarian Krukenberg tumor secondary to a gastric carcinoma. In the mother, basal hormonal studies were done 1 and 4 weeks after delivery, then after gastric and ovarian surgery. Three months after delivery, ovarian steroid response to hCG (priming dose, 5000 IU; then 1500 IU every other day for 12 days) and a study of progesterone (P) metabolism at a steady state after a constant infusion of [3H]P and cold P (92 micrograms/min leads to blood production rate (BPR) of 152 mg/day designed to reproduce the BPR of P usually seen in pregnancy) were successively performed. Hormones were measured by specific RIAs after chromatographical purification. Basal hormonal levels were normal in the child. In the mother, on the 5th day postpartum, mean hormone levels (in nanograms per dl) were: testosterone (T), 4181; androstenedione (delta 4), 8876; 17 alpha-hydroxyprogesterone (17-OHP), 9746; P 1075; estrone (E1), 195; and estradiol (E2), 151. One month later, levels were normal for the follicular phase; T, 40; delta 4, 146; P, 52; E2, 9; and E2, 4.5. At both times, dehydroepiandrosterone was normal (703-750). Hormone levels increased progressively during hCG stimulation but their time course was different between hormones. At the end of the test, T. 144; delta 4, 746;' 17-OHP, 789; P, 723; E1, 37; and E2, 20. The MCR of P was decreased, 1450 liters/day (normal, 2020). Conversion ratios between products and precursor during constant infusion were normal. From these data, obtained in four different conditions (postpartum period, hCG stimulation, progesterone infusion, and after oophorectomy), the following can be concluded: adrenal production of dehydroepiandrosterone was normal; the ovarian overproduction of androgens likely resulted from the excessive reductive metabolism of both placental and ovarian P along the delta 4 steroid biosynthetic pathway by an hypertrophic stromal compartment; and HCG stimulation seems to be the necessary stimulus for this condition. The enhancement by T on its own peripheral production is also discussed.


Assuntos
Androgênios/sangue , Neoplasias Ovarianas/complicações , Complicações Neoplásicas na Gravidez/fisiopatologia , Virilismo/etiologia , Androgênios/biossíntese , Gonadotropina Coriônica , Estrogênios/sangue , Feminino , Humanos , Recém-Nascido , Cinética , Neoplasias Ovarianas/fisiopatologia , Gravidez , Progesterona/metabolismo
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