Hemoglobin Providence (β82 Lys > Asn, Asp) and lower-than-expected HbA1c in a nonadherent teenager with type 1 diabetes: a case report and literature review.

Endocrinologists should have a high index of suspicion for a Hb variant when the HbA1c is not consistent with other indices of glycemic control.

Decreased heart rate variability is associated with increased transcranial Doppler velocities in children with sickle cell disease.

Objective: To explore the relationship between 24-hour blood pressure (BP) variability, heart rate (HR) variability, and transcranial Doppler velocity (TCDV) in a cohort of pediatric sickle cell disease (SCD) patients.

Design, Setting, And Participants: This is a retrospective study of 11 children aged 8-18 years with SCD who previously underwent 24-hour ambulatory BP monitoring and TCDV measurements.

Interventions: Medical records were reviewed for TCDV and 24-hour ABP data.

Estrogen elevates the peak overnight production rate of acylated ghrelin.

Context: Acylated ghrelin is the putatively bioactive GH secretagogue.

Hypothesis: Estradiol (E2) stimulates the synthesis rather than inhibits the metabolic clearance of acylated ghrelin.

Setting: The study took place at an academic medical center.

Estrogen supplementation selectively enhances hypothalamo-pituitary sensitivity to ghrelin in postmenopausal women.

Context: Sex-steroid hormones amplify pulsatile GH secretion by unknown mechanisms. Ghrelin is the most potent natural GH secretagogue discovered to date. A plausible unifying postulate is that estradiol (E(2)) enhances hypothalamo-pituitary sensitivity to ghrelin (a physiological effect).

Gonadal status and body mass index jointly determine growth hormone (GH)-releasing hormone/GH-releasing peptide synergy in healthy men.

Context: Sex steroid hormones potentiate whereas increased body mass index (BMI) represses GH secretion. Whether sex steroids modify the negative effect of BMI on secretagogue-induced GH secretion in men is not known. The issue is important in designing GH-stimulation regimens that are relatively insensitive to both gonadal status and adiposity.