The Journal of clinical endocrinology and metabolism
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J. Clin. Endocrinol. Metab. · Jun 2004
Clinical TrialEarly adrenocortical recovery after glucocorticoid therapy in children with leukemia.
The duration of glucocorticoid-induced inhibition that occurs in the hypothalamic-pituitary-adrenal (HPA) axis after discontinuation of treatment is controversial. The main objective of this prospective study was to evaluate the inhibition of the HPA axis by dexamethasone in children and adolescents with acute lymphoid leukemia. Thirty-five patients (median age of 6.9 yr) were evaluated. ⋯ Suppression of the adrenal function was detected during glucocorticoid therapy, which persisted for 48 h after the steroid was removed from treatment (P < 0.01). One month after ceasing the administration of the glucocorticoid, the adrenal function was similar to that before glucocorticoid therapy. According to these results, a clinical and laboratory follow-up of the HPA axis in the month after the cessation of dexamethasone therapy is suggested to determine glucocorticoid replacement.
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J. Clin. Endocrinol. Metab. · Jun 2004
Multicenter Study Comparative StudyBody size and ethnicity are associated with menstrual cycle alterations in women in the early menopausal transition: The Study of Women's Health across the Nation (SWAN) Daily Hormone Study.
The dynamics of reproductive hormones that characterize the menopausal transition (perimenopause) are incompletely understood, particularly in non-Caucasian women. The Study of Women's Health across the Nation (SWAN) is a multiethnic cohort study of 3302 women at seven sites who were aged 42-52 yr at baseline. All participants are seen annually to assess a variety of endpoints. ⋯ When compared with cycles of younger control women, the cycles of the SWAN DHS participants had higher gonadotropins, lower total integrated Pdg, and E1c levels that were not different, which suggests that the ovary retains sensitivity to elevated FSH in the early menopausal transition. In this cross-sectional study of women over age 42 who are premenopausal or in the early menopausal transition, there were important differences in the characteristics of cycles related to age, body mass index, and ethnicity. Comparisons to younger women indirectly support the inhibin hypothesis, which proposes that the initiating event in the menopausal transition is the loss of inhibin negative feedback on FSH secondary to a diminished follicular reserve.
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J. Clin. Endocrinol. Metab. · Jun 2004
Randomized Controlled Trial Clinical TrialNon-acylated ghrelin counteracts the metabolic but not the neuroendocrine response to acylated ghrelin in humans.
Ghrelin possesses strong GH-releasing activity but also other endocrine activities including stimulation of PRL and ACTH secretion, modulation of insulin secretion and glucose metabolism. It is assumed that the GH secretagogue (GHS) receptor (GHS-R) 1a mediates ghrelin actins provided its acylation in Serine 3; in fact, acylated ghrelin only is able to exert endocrine activities. Acylated ghrelin (AG) is present in serum at a 2.5 fold lower concentration than unacylated ghrelin (UAG). ⋯ In conclusion, non-acylated ghrelin does not affect the GH, PRL, and ACTH response to acylated ghrelin but is able to antagonize the effects of acylated ghrelin on insulin secretion and glucose levels. These findings indicate that unacylated ghrelin is metabolically active and is likely to counterbalance the influence of acylated ghrelin on insulin secretion and glucose metabolism. As GHS-R1a is not bound by unacylated ghrelin, these findings suggest that GHS receptor subtypes mediate the metabolic actions of both acylated and unacylated ghrelin.