A Case Report of Syndromic Multinodular Goitre in Adolescence: Exploring the Phenotype Overlap between Cowden and DICER1 Syndromes.

BACKGROUND: Hereditary tumour predisposition syndromes may increase the risk for development of thyroid nodules at a young age. We present the case of an adolescent female with Cowden syndrome who had some atypical phenotypic features which overlapped with the DICER1 syndrome. MATERIAL AND METHODS: A 17-year-old female presented with a 3-month history of progressive right neck swelling. Fine needle cytology of the thyroid revealed a follicular neoplasm with features suggestive of follicular variant of papillary thyroid carcinoma and she underwent a hemithyroidectomy. Enlarging nodules in the remaining thyroid led to a completion thyroidectomy at 19 years of age. The patient's past medical history included an ovarian mixed malignant germ cell tumour, pulmonary nodules and cysts, renal cysts, mucocutaneous lesions, an arachnoid cyst, and a fibrous breast lesion. Macrocephaly was noted on physical examination. RESULTS: Based on the patient's complex phenotype and young age, a hereditary predisposition syndrome was suspected and genetic testing of PTEN and DICER1 was undertaken. A heterozygous truncating germ-line PTEN mutation was identified, which combined with clinical findings, met criteria for the diagnosis of Cowden syndrome. Additional loss of heterozygosity of the wild-type PTEN allele was detected in the right thyroid lesion and ovarian tumour. No DICER1 mutations were identified. CONCLUSIONS: Genetic testing was crucial in elucidating this patient's predisposition to the early development of neoplastic and non-neoplastic conditions. Our report also highlights the phenotypic overlap between the Cowden and DICER1 syndromes and illustrates the importance of recognising the variable phenotypic features of hereditary syndromes in order to enable timely implementation of appropriate care.

The majority of irregular menstrual cycles in adolescence are ovulatory: results of a prospective study.

PURPOSE: While ovulation is most likely to occur in adolescent girls with regular menstrual cycles, there are limited data on the incidence of ovulation in girls with irregular menstrual cycles in early postmenarcheal years. The aim of the study was to evaluate the presence of ovulation in healthy postmenarcheal girls with irregular menstrual cycles. METHODS, DESIGN AND SUBJECTS: Prospective cohort study over 12 weeks including 40 healthy postmenarcheal girls recruited from the population-based cohort of adolescents from Western Australian Pregnancy Cohort (Raine) Study with irregular menstrual cycles defined by either menstrual cycles <21 days or >35 days in duration or cycle length that varied from month to month by >4 days according to menstrual diaries. MAIN OUTCOME MEASURE: Ovulation defined by urinary pregnanediol-3α-glucuronide/creatinine measurements higher than three times above minimum value obtained from 12 samples (1 per week). RESULTS: Forty girls (37 Caucasians) with irregular menstrual cycles aged 15.1 (median (IQR) 14.9-15.4) years who were 2.3 (1.9-3.3) years postmenarche were assessed. Urinary pregnanediol-3α-glucuronide/creatinine values identified that 33 girls (82.5%) ovulated during the 3 months of observation and 7 girls had anovulatory cycles. Menstrual diaries collected for a median (IQR) of 159 (137.5-188.2) days showed median minimal and maximum menstrual cycle duration of 24 (11.5-29) and 38.5 (35-48) days, respectively. CONCLUSIONS: A large proportion of healthy adolescent girls with irregular menstrual cycles are still ovulating despite irregular and infrequent menses.

Fitness, body composition and vascular health in adolescent and young adult survivors of paediatric brain cancer and cranial radiotherapy.

Background Survivors of paediatric brain cancer and/or cranial radiotherapy (CRT) are at an increased risk of developing serious comorbidities. Established risk factors for chronic disease include central obesity, endothelial abnormalities and diminished fitness. Objectives Here we characterised anthropometry, body composition, bone mineral density (BMD), heart rate (HR), blood pressure (BP), endothelial function, muscular strength and endurance and aerobic fitness in adolescent and young adult (AYA) survivors. Methods Twenty survivors (10 male, 10 female; 20 ± 2 years) were compared with 19 matched controls. Muscular strength was assessed using three repetition maximum tests, while muscular endurance was determined as number of repetitions performed per minute. Peak oxygen uptake (VO2 peak) was assessed on a treadmill using a modified chronotropic protocol. Anthropometric measurements, HR and BP were taken using standard clinical protocols, while body composition and BMD were determined using dual X-ray absorptiometry (DXA). Endothelial function was measured using the flow mediated dilation technique. Results Survivors demonstrated deficits in muscular strength (latissimus dorsi pull-down, p = 0.020; bicep curl, p = 0.009), muscular endurance (squats, p = 0.012; sit-ups, p = 0.030; push-ups, p = 0.013), minute ventilation at peak exericse (p = 0.002) and VO2peak (L/min, p = 0.002; mL/kg/min, p = 0.008; mL/kg LBM/min, p = 0.010). Additionally, survivors had greater waist-to-hip ratios (p = 0.032), resting HR (p = 0.048) and higher percentage of total body (p = 0.017), central (p = 0.009) and peripheral (p = 0.032) fat. Lean body mass (p = 0.004) and BMD (p = 0.005) were lower in the survivor group. Conclusion AYA survivors of paediatric brain cancer and/or CRT exhibit altered body composition, increased resting HR and reduced BMD, muscular strength, muscular endurance and cardiorespiratory fitness compared to controls.

Increased Body Mass Index during Therapy for Childhood Acute Lymphoblastic Leukemia: A Significant and Underestimated Complication.

Objective & Design. We undertook a retrospective review of children diagnosed with acute lymphoblastic leukemia (ALL) and treated with modern COG protocols (n = 80) to determine longitudinal changes in body mass index (BMI) and the prevalence of obesity compared with a healthy reference population. Results. At diagnosis, the majority of patients (77.5%) were in the healthy weight category. During treatment, increases in BMI z-scores were greater for females than males; the prevalence of obesity increased from 10.3% to 44.8% (P < 0.004) for females but remained relatively unchanged for males (9.8% to 13.7%, P = 0.7). Longitudinal analysis using linear mixed-effects identified associations between BMI z-scores and time-dependent interactions with sex (P = 0.0005), disease risk (P < 0.0001), age (P = 0.0001), and BMI z-score (P < 0.0001) at diagnosis and total dose of steroid during maintenance (P = 0.01). Predicted mean BMI z-scores at the end of therapy were greater for females with standard risk ALL irrespective of age at diagnosis and for males younger than 4 years of age at diagnosis with standard risk ALL. Conclusion. Females treated on standard risk protocols and younger males may be at greatest risk of becoming obese during treatment for ALL. These subgroups may benefit from intervention strategies to manage BMI during treatment for ALL.

Long-acting progestin-only contraceptives impair endometrial vasculature by inhibiting uterine vascular smooth muscle cell survival.

Molecular mechanisms responsible for abnormal endometrial vasculature in women receiving long-acting progestin-only contraceptives (LAPCs) are unknown. We hypothesize that LAPCs impair vascular smooth muscle cell (VSMC) and pericyte proliferation and migration producing thin-walled hyperdilated fragile microvessels prone to bleeding. Proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (αSMA) double-immunostaining assessed VSMC differentiation and proliferation in endometria from women before and after DepoProvera (Depo) treatment and from oophorectomized guinea pigs (OVX-GPs) treated with vehicle, estradiol (E2), medroxyprogesterone acetate (MPA), or E2+MPA. Whole-genome profiling, proliferation, and migration assays were performed on cultured VSMCs treated with MPA or etonogestrel (ETO). Endometrial vessels of Depo-administered women displayed reduced αSMA immunoreactivity and fewer PCNA (+) nuclei among αSMA (+) cells (P < 0.008). Microarray analysis of VSMCs identified several MPA- and ETO-altered transcripts regulated by STAT1 signaling (P < 2.22 × 10(-6)), including chemokine (C-C motif) ligand 2 (CCL2). Both MPA and ETO reduce VSMC proliferation and migration (P < 0.001). Recombinant CCL2 reversed this progestin-mediated inhibition, whereas a STAT1 inhibitor abolished the CCL2 effect. Similarly, the endometria of MPA treated OVX-GPs displayed decreased αSMA staining and fewer PCNA (+) nuclei in VSMC (P < 0.005). In conclusion, LAPCs promote abnormal endometrial vessel formation by inhibiting VSMC proliferation and migration.

Investigation of genetic variants, birthweight and hypothalamic-pituitary-adrenal axis function suggests a genetic variant in the SERPINA6 gene is associated with corticosteroid binding globulin in the western Australia pregnancy cohort (Raine) study.

BACKGROUND: The hypothalamic-pituitary-adrenal (HPA) axis regulates stress responses and HPA dysfunction has been associated with several chronic diseases. Low birthweight may be associated with HPA dysfunction in later life, yet human studies are inconclusive. The primary study aim was to identify genetic variants associated with HPA axis function. A secondary aim was to evaluate if these variants modify the association between birthweight and HPA axis function in adolescents. METHODS: Morning fasted blood samples were collected from children of the Western Australia Pregnancy Cohort (Raine) at age 17 (n = 1077). Basal HPA axis function was assessed by total cortisol, corticosteroid binding globulin (CBG), and adrenocorticotropic hormone (ACTH). The associations between 124 tag single nucleotide polymorphisms (SNPs) within 16 HPA pathway candidate genes and each hormone were evaluated using multivariate linear regression and penalized linear regression analysis using the HyperLasso method. RESULTS: The penalized regression analysis revealed one candidate gene SNP, rs11621961 in the CBG encoding gene (SERPINA6), significantly associated with total cortisol and CBG. No other candidate gene SNPs were significant after applying the penalty or adjusting for multiple comparisons; however, several SNPs approached significance. For example, rs907621 (p = 0.002) and rs3846326 (p = 0.003) in the mineralocorticoid receptor gene (NR3C2) were associated with ACTH and SERPINA6 SNPs rs941601 (p = 0.004) and rs11622665 (p = 0.008), were associated with CBG. To further investigate our findings for SERPINA6, rare and common SNPs in the gene were imputed from the 1,000 genomes data and 8 SNPs across the gene were significantly associated with CBG levels after adjustment for multiple comparisons. Birthweight was not associated with any HPA outcome, and none of the gene-birthweight interactions were significant after adjustment for multiple comparisons. CONCLUSIONS: Our study suggests that genetic variation in the SERPINA6 gene may be associated with altered CBG levels during adolescence. Replication of these findings is required.

Regulation of the hypothalamic-pituitary-adrenal axis circadian rhythm by endocannabinoids is sexually diergic.

We have examined the effects of acute administration of the cannabinoid receptor type 1 (CB(1)) antagonist AM251 on the rat hypothalamic-pituitary-adrenal (HPA) axis with respect to both gender and time of day. Blood samples were collected from conscious male and female rats every 5 min using an automated blood sampling system, and corticosterone concentrations were determined. In male rats, there was a distinct diurnal effect of AM251 with a greater activation of the HPA axis in the morning (diurnal trough) compared with the evening (diurnal peak). At both times of the day, circulating corticosterone concentrations were elevated for approximately 4 h after AM251 administration. In female rats, there was also diurnal variation in the activation of the HPA axis; however, these effects were not as profound as those in males. Corticosterone concentrations were only slightly elevated at the diurnal trough and for a shorter time period than in males (2 compared with 4 h). Moreover, there was no effect of AM251 on corticosterone concentrations when administered at the diurnal peak. Subsequent studies, only in males, in which both ACTH and corticosterone were measured, confirmed that the effects of AM251 on corticosterone were mediated by ACTH. Moreover, the elevation of both ACTH and corticosterone could be replicated using another CB(1) antagonist, AM281. These data demonstrate that the extent and duration of HPA axis activation after CB(1) blockade are clearly dependent on both gender and time of day.

Circulating maternal testosterone concentrations at 18 weeks of gestation predict circulating levels of antimüllerian hormone in adolescence: a prospective cohort study.

This prospective study was established to determine the impact of maternal circulating androgen levels during normal pregnancy on ovarian function, as determined by early follicular phase antimüllerian hormone (AMH) levels, inhibin B levels, and antral follicle count (AFC) in 244 female offspring in adolescence. Maternal circulating total testosterone levels at 18 weeks' gestation were statistically significantly correlated with early follicular-phase circulating AMH levels in female adolescent offspring, but no other statistically significant correlations were determined among the maternal androgens at 18 or 34 weeks of gestation and the markers of adolescent ovarian function.

Prenatal determinants of uterine volume and ovarian reserve in adolescence.

CONTEXT: Adequate uterine volume and ovarian reserve are essential for reproductive health. Antenatal events such as restricted fetal growth and maternal tobacco smoking are hypothesized to impact on reproductive function in later life, although not studied in a large prospective normal pregnancy population to date. OBJECTIVE: The objective of the study was to determine the relationship between intrauterine growth, birth weight, and maternal tobacco smoking on uterine volume and ovarian reserve in adolescence. DESIGN AND SETTING: This was a prospective study in which half the cohort underwent intensive ultrasound monitoring in utero. PARTICIPANTS: Intrauterine growth was measured using ultrasound at 18, 24, 28, and 34/36 wk gestation (n = 115 girls). Maternal smoking data were prospectively collected at 18 and 34/36 wk from the whole cohort. Uterine (n = 229) and early follicular ovarian volume and antral follicle count (n = 225) were measured using transabdominal ultrasound (n = 230). Ovarian reserve was estimated using early follicular phase anti-Mullerian hormone, inhibin B, and FSH (n = 213). MAIN OUTCOME MEASURES: The relationship between maternal tobacco smoking, intrauterine growth trajectories, and markers of ovarian reserve and uterine size in adolescence was measured. RESULTS: Linear regression showed that daughters of mothers who smoked had a significantly smaller uterus compared with nonsmokers (P = 0.019). No significant relationship between maternal tobacco smoking and ovarian volume (P = 0.164) or markers of ovarian reserve (antral follicle count, plasma FSH, anti-Mullerian hormone, and inhibin B) in adolescence was determined. CONCLUSIONS: Our findings indicate that maternal smoking, but not variations in fetal growth, may lead to a reduction in uterine volume and does not appear to impact ovarian reserve.

Corticosterone levels in the brain show a distinct ultradian rhythm but a delayed response to forced swim stress.

Circulating corticosterone levels show an ultradian rhythm resulting from the pulsatile release of glucocorticoid hormone by the adrenal cortex. Because the pattern of hormone availability to corticosteroid receptors is of functional significance, it is important to determine whether there is also a pulsatile pattern of corticosterone concentration within target tissues such as the brain. Furthermore, it is unclear whether measurements of plasma corticosterone levels accurately reflect corticosterone levels in the brain. Given that the hippocampus is a principal site of glucocorticoid action, we investigated in male rats hippocampal extracellular corticosterone concentrations under baseline and stress conditions using rapid-sampling in vivo microdialysis. We found that hippocampal extracellular corticosterone concentrations show a distinct circadian and ultradian rhythm. The PULSAR algorithm revealed that the pulse frequency of hippocampal corticosterone is 1.03 +/- 0.07 pulses/h between 0900 and 1500 h and is significantly higher between 1500 and 2100 h (1.31 +/- 0.05). The hippocampal corticosterone response to stress is stressor dependent but resumes a normal ultradian pattern rapidly after the termination of the stress response. Similar observations were made in the caudate putamen. Importantly, simultaneous measurements of plasma and hippocampal glucocorticoid levels showed that under stress conditions corticosterone in the brain peaks 20 min later than in plasma but clears concurrently, resulting in a smaller exposure of the brain to stress-induced hormone than would be predicted by plasma hormone concentrations. These data are the first to demonstrate that the ultradian rhythm of corticosterone is maintained over the blood-brain barrier and that tissue responses cannot be reliably predicted from the measurement of plasma corticosterone levels.

Corticosteroids mediate fast feedback of the rat hypothalamic-pituitary-adrenal axis via the mineralocorticoid receptor.

The aim of this study was to investigate fast corticosteroid feedback of the hypothalamic-pituitary-adrenal (HPA) axis under basal conditions, in particular the role of the mineralocorticoid receptor. Blood samples were collected every 5 min from conscious rats at the diurnal peak, using an automated blood sampling system, and assayed for corticosterone. Feedback inhibition by rapidly increasing concentrations of ligand was achieved with an intravenous bolus of exogenous corticosteroid. This resulted in a significant reduction in plasma corticosterone concentrations within 23 min of the aldosterone bolus and 28 min of methylprednisolone. Evaluation of the pulsatile secretion of corticosterone revealed that the secretory event in progress at the time of administration of exogenous steroid was unaffected, whereas the next secretory event was inhibited by both aldosterone and methylprednisolone. The inhibitory effect of aldosterone was limited in duration (1 secretory event only), whereas that of methylprednisolone persisted for 4-5 h. Intravenous administration of canrenoate (a mineralocorticoid receptor antagonist) also had rapid effects on the HPA axis, with an elevation of ACTH within 10 min and corticosterone within 20 min. The inhibitory effect of aldosterone was unaffected by pretreatment with the glucocorticoid receptor antagonist RU-38486 but blocked by the canrenoate. These data imply an important role for the mineralocorticoid receptor in fast feedback of basal HPA activity and suggest that mineralocorticoids can dynamically regulate basal corticosterone concentrations during the diurnal peak, a time of day when there is already a high level of occupancy of the cytoplasmic mineralocorticoid receptor.

The significance of glucocorticoid pulsatility.

Glucocorticoids are secreted in discrete pulses resulting in an ultradian rhythm in all species that have been studied. In the rat there is an approximately hourly rhythm of corticosterone secretion, which appears to be regulated by alternating activation and inhibition of the HPA axis. At the level of signal transduction, the response to these pulses of corticosterone is determined by its dynamic interaction with the two transcription factors--the glucocorticoid and mineralocorticoid receptors. While the mineralocorticoid receptor remains activated throughout the ultradian cycle, the glucocorticoid receptor shows a phasic response to each individual pulse of corticosterone. This phasic response is regulated by an intranuclear proteasome-dependent rapid downregulation of the activated glucocorticoid receptor.

Proteasome-dependent down-regulation of activated nuclear hippocampal glucocorticoid receptors determines dynamic responses to corticosterone.

Timing is a critical factor in neuroendocrinology. Despite this, the temporal aspects of glucocorticoid signaling in the regulation of in vivo targets have been largely overlooked. Here, we present data showing that plasma glucocorticoid levels differ greatly from the constant signal predominantly used in cell culture experiments. Using an automated blood sampling system, we found that under basal conditions in nonstressed rats, corticosterone release occurs in discrete pulses of various amplitudes dependent on the circadian cycle. This basal pattern changes to a prolonged elevated nonpulsatile release in response to stressful stimuli. We have been able to recapitulate these different patterns of corticosterone presentation (short pulse vs. prolonged elevation) in adrenalectomized rats, and show that each pattern results in differential activation of hippocampal glucocorticoid and mineralocorticoid receptors. Finally, we provide evidence for a rapid proteasome-dependent clearance of activated glucocorticoid receptors, but not mineralocorticoid receptors, as a novel mechanism to allow dynamic interaction with rapidly changing physiological and environmental conditions.