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1.
J Dev Orig Health Dis ; 13(1): 28-38, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33787479

RESUMO

Testosterone (T) and cortisol (C) are steroid hormones that have been argued to play opposing roles in shaping physical and behavioral development in humans. While there is evidence linking T and C to different memory processes during adulthood, it remains unclear how the relative levels of T and C (TC ratio) may influence brain and behavioral development, whether they are influenced by sex of the child, and whether or not they occur as a result of stable changes in brain structure (organizational changes), as opposed to transient changes in brain function (activational changes). As such, we tested for associations among TC ratio, cortico-hippocampal structure, and standardized tests of executive, verbal, and visuo-spatial function in a longitudinal sample of typically developing 4-22-year-old children and adolescents. We found greater TC ratios to be associated with greater coordinated growth (i.e. covariance) between the hippocampus and cortical thickness in several areas primarily devoted to visual function. In addition, there was an age-related association between TC ratio and parieto-hippocampal covariance, as well as a sex-specific association between TC ratio and prefrontal-hippocampal covariance. Differences in brain structure related to TC ratio were in turn associated with lower verbal/executive function, as well as greater attention in tests of visuo-spatial abilities. These results support the notion that TC ratio may shift the balance between top-down (cortex to hippocampus) and bottom-up (hippocampus to cortex) processes, impairing more complex, cortical-based tasks and optimizing visuospatial tasks relying primarily on the hippocampus.


Assuntos
Hidrocortisona/análise , Testosterona/análise , Adolescente , Criança , Pré-Escolar , Cognição , Feminino , Humanos , Hidrocortisona/sangue , Hidrocortisona/classificação , Sistema Hipotálamo-Hipofisário/enzimologia , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Saliva/química , Testosterona/sangue , Testosterona/classificação
2.
Fed Regist ; 74(232): 63603-10, 2009 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-20169675

RESUMO

With the issuance of this final rule, the Deputy Administrator of the Drug Enforcement Administration (DEA) classifies the following three steroids as "anabolic steroids" under the Controlled Substances Act (CSA): Boldione, desoxymethyltestosterone, and 19-nor-4,9(10)-androstadienedione. These steroids and their salts, esters, and ethers are schedule III controlled substances subject to the regulatory control provisions of the CSA.


Assuntos
Anabolizantes/classificação , Androstadienos/classificação , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Metiltestosterona/classificação , Esteroides/classificação , Testosterona/classificação , Humanos , Legislação de Medicamentos , Testosterona/análise , Estados Unidos
3.
Hell J Nucl Med ; 8(1): 39-42, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15886752

RESUMO

Several studies have suggested that estrogen replacement therapy lowers the risk of Alzheimer's dementia (AD) among postmenopausal women. Other studies have evaluated serum levels of sex hormones and gonadotropins in women with AD. Estrogens (E(1) and E(2)), luteinizing hormone (LH) and follicular stimulating hormone (FSH), dihydroepiandrosterone and sex hormone binding albumin, which normally responds to circulating testosterone, have been investigated by others using the same protocol in postmenopausal women with AD, older than 65 years. Others have studied in elderly women with AD, also using one protocol, fewer sex hormones and/or gonadotropins. We have studied the serum levels of estradiol, progesterone, testosterone, LH and FSH in the same serum sample of postmenopausal women with AD and other dementias and compared them to a group of controls. We are not aware of a similar study in the literature. All patients were diagnosed on clinical grounds and screened by the mini mental score examination (MMSE). Forty eight women had AD (Group A), mean age 72 years and age range 60-84 years, s even had other types of dementia (Group B), mean age 63.5 years and age range 53-74 years and 33 women had no cognitive impairment and were studied as controls (Group C). Group C women had mean age of 65 years and their age ranged between 55-73 years. Estradiol, progesterone and testosterone were measured by radioimmunoassay (RIA), while FSH and LH by radioimmunometric assay (IRMA). Our results showed that estradiol was significantly lower in Group A as compared to Group C (P=0.04). There was no significant difference in the levels of the other four hormones in the three Groups as studied by the Mann-Whitney U and the Pearson's statistical test. Our results were not influenced by differences due to sex, age, ethnic group or education since these factors were either similar or comparable in all Groups studied. All but two of the subjects, with mild alcoholism, smoking, increased BMI and chronic diseases, had all five hormones studied within reference limits. We consider that the absence of difference we found in the four hormone levels, in Groups A, B and C may be related to free hormones, to the different stage of AD of our patients, to intra assay variability, to assay sensitivity or to other non specified factors. Future study may be directed towards whether a primary or secondary hypogonadism exists in AD and whether hormones are contributing to or are the result of brain degeneration in AD.


Assuntos
Doença de Alzheimer/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Pós-Menopausa/sangue , Progesterona/sangue , Testosterona/classificação , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade
5.
J Clin Endocrinol Metab ; 80(11): 3298-303, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7593442

RESUMO

The purpose of this study was to delineate the possible endocrine effects of exercise-induced GH secretion. Twelve healthy adult males were studied during short (20 min) and subsequent prolonged (2 h) physical exercise and recovery period (2 h), both after injection of a long acting somatostatin analog [Sandostatin (ST); 0.1 or 0.05 mg, sc] and after a control saline injection. Additional subjects were studied during rest with similar injections of ST (0.1 mg) and saline (n = 7) or using a lower ST dose (0.01 mg; n = 6). Several venous blood samples were taken during the trials and analyzed for selected hormones, monitoring pituitary, testicular, and adrenal functions. ST injection blocked the serum GH response to short term maximal bicycle ergometer exercise, but not to the following prolonged bicycle exercise. No relationship of the exercise-associated GH increase to the concomitant endocrine responses of the adrenals and testes was observed. Unexpectedly, the higher ST doses (0.1 and 0.05 mg) increased the mean levels of serum testosterone by 18-25% in both exercise (P = 0.0017) and rest trials (P < 0.0001), respectively. ST did not affect the levels of LH, FSH, or cortisol. ST slightly increased serum sex hormone-binding globulin (3%; P = 0.021) and albumin (4%; P = 0.017) concentrations, but not that of free testosterone. Because the testosterone response to somatostatin was fast and without a simultaneous increase in LH, it was consistent with a direct testicular response. The explanation for this novel ST effect remains obscure, but it may be due to modulation of some paracrine mechanisms inhibiting testicular steroidogenesis.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Hormônios/farmacologia , Octreotida/farmacologia , Esforço Físico , Hipófise/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/metabolismo , Glândulas Suprarrenais/fisiologia , Adulto , Relação Dose-Resposta a Droga , Humanos , Masculino , Hipófise/fisiologia , Descanso , Método Simples-Cego , Testículo/fisiologia , Testosterona/classificação
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