Self-rated Tanner stage and subjective measures of puberty are associated with longitudinal gonadal hormone changes.

Introduction In large community-based studies of puberty, Tanner staging by a clinician is often not possible. We compared self-rated Tanner staging and other subjective ratings of pubertal development with serum hormone levels measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to reassess the utility of self-rated pubertal stage using highly sensitive and specific hormone analysis. Methods Adolescents and their parents enrolled in the Adolescent Rural Cohort study of Hormones and health, Education, environments and Relationships (ARCHER) answered annual survey questions on pubertal development. Annually, adolescents provided blood samples for serum testosterone and estradiol measured by LC-MS/MS. Results Longitudinally, self-rated Tanner stage was positively associated with serum testosterone and estradiol levels in both sexes. Confirmation by adolescent and parent that puberty had commenced was associated with higher gonadal hormone levels in both sexes. Parent and adolescent responses demonstrated 'fair' to 'moderate' agreement. Conclusions Over a 3-year follow-up, self-rated Tanner staging and simple questions regarding pubertal onset and development are positively associated with adolescent gonadal hormone concentrations in serum measured by mass spectrometry. Thus, self-report of puberty stage still has a role in large community-based studies where physical examination is not feasible.

Salivary cortisol reveals overt and hidden anxiety in survivors of childhood cancer attending clinic.

BACKGROUND: Symptoms of anxiety may arise from fear of cancer recurrence and memories of traumatic experiences during treatment. This study aimed to identify changes in mental health and cortisol, a biological marker of stress, associated with oncology surveillance clinic attendance. METHODS: Adolescent and young adult (AYA) survivors of childhood cancer (aged 12-30 years, N = 46) attending a survivorship clinic were recruited. The State-Trait Anxiety Inventory, an anxiety self-rating and open answer question, and salivary cortisol collections were completed two weeks before and one day before clinic, on clinic day and two weeks after. RESULTS: Trait anxiety scores were consistent with the normal population. State anxiety scores two weeks after clinic were significantly lower than baseline (p = 0.02). Cortisol diurnal slopes were flatter than baseline after clinic (p = 0.02). Evening cortisol levels were significantly higher than baseline two weeks post clinic (p = 0.02). LIMITATIONS: Combined results from biological and psychometric assessments can be difficult to interpret. Larger cohorts will further delineate cortisol pathway activity and distress in AYA cancer survivors. CONCLUSIONS: Psychometric evidence indicates that AYA survivors of childhood cancer perceive themselves to be less anxious after a survivorship clinic visit. Biological evidence, however, indicates a dysregulation of the hypothalamic-pituitary-adrenal axis which may be linked to clinic attendance. Weak correlations suggest that cortisol may not be a reliable indicator of self-perceived anxiety. This may be due to confounding lifestyle factors influencing the stress response or potential 'coping strategies' developed during past treatment experience which may, hypothetically, have masked self-perceived anxiety.

Dopamine-2 receptor extracellular N-terminus regulates receptor surface availability and is the target of human pathogenic antibodies from children with movement and psychiatric disorders.

Anti-Dopamine-2 receptor (D2R) antibodies have been recently identified in a subgroup of children with autoimmune movement and psychiatric disorders, however the epitope(s) and mechanism of pathogenicity remain unknown. Here we report a major biological role for D2R extracellular N-terminus as a regulator of receptor surface availability, and as a major epitope targeted and impaired in brain autoimmunity. In transfected human cells, purified anti-D2R antibody from patients specifically and significantly reduced human D2R surface levels. Next, human D2R mutants modified in their extracellular domains were subcloned, and we analyzed the region bound by 35 anti-D2R antibody-positive patient sera using quantitative flow cytometry on live transfected cells. We found that N-glycosylation at amino acids N5 and/or N17 was critical for high surface expression in interaction with the last 15 residues of extracellular D2R N-terminus. No anti-D2R antibody-positive patient sera bound to the three extracellular loops, but all patient sera (35/35) targeted the extracellular N-terminus. Overall, patient antibody binding was dependent on two main regions encompassing amino acids 20 to 29, and 23 to 37. Residues 20 to 29 contributed to the majority of binding (77%, 27/35), among which 26% (7/27) sera bound to amino acids R20, P21, and F22, 37% (10/27) patients were dependent on residues at positions 26 and 29, that are different between humans and mice, and 30% (8/27) sera required R20, P21, F22, N23, D26, and A29. Seven patient sera bound to the region 23 to 37 independently of D26 and A29, but most sera exhibited N-glycosylation-independent epitope recognition at N23. Interestingly, no evident segregation of binding pattern according to patient clinical phenotype was observed. D2R N-terminus is a central epitope in autoimmune movement and psychiatric disorders and this knowledge could help the design of novel specific immune therapies tailored to improve patient outcome.

Energy expenditure and intake during puberty in healthy nonobese adolescents: a systematic review.

BACKGROUND: Puberty is a time of rapid growth and changing energy requirements and is a risk period for obesity. There is little high-quality evidence on the pubertal alterations of energy expenditure and intake, and this has limited our understanding of energy balance during this important life stage. OBJECTIVE: The purpose of this study was to summarize existing evidence on pubertal energy expenditure and intake in healthy nonobese adolescents. DESIGN: Studies were identified through CINAHL, the Cochrane Library, Embase, MEDLINE, and Web of Science databases up to August 2015. Articles presenting objectively measured data for basal or resting metabolic rate (BMR/RMR), total daily energy expenditure (TDEE), and/or energy intake (EI) for ≥2 categories of puberty were included. Relevant data adjusted for fat-free mass (FFM) also were extracted. Data were dichotomized into prepubertal and pubertal groups and compared through the use of standardized mean differences (SMDs). Heterogeneous study methodologies precluded meta-analysis. RESULTS: The search netted 6770 articles, with 12 included for review. From these, 6 of 9 studies supported significantly higher absolute BMR/RMR during puberty (SMD: 1.10-5.93), and all of the studies favored significantly higher absolute TDEE during puberty (SMD: 0.46-9.55). These corresponded to a 12% difference and an 18% difference in absolute BMR/RMR and TDEE, respectively. Results adjusted for FFM were equivocal, with 3 studies favoring higher (1 significantly) and 3 favoring significantly lower adjusted BMR/RMR during puberty. Only 1 study reported EI, showing 41% and 25% greater absolute intakes in pubertal males and females, respectively. These differences were not significant after adjustment for FFM. CONCLUSIONS: Reasonably consistent evidence exists to support higher absolute BMR/RMR and TDEE in pubertal than in prepubertal adolescents. Differences are largely accounted for by FFM, among other potential factors such as growth- and puberty-related hormones. This review argues for further research into hormonal influences on pubertal energy balance and subsequent effects on obesity risk.

Utility of salivary enzyme immunoassays for measuring estradiol and testosterone in adolescents: a pilot study.

AIM: We investigated the utility of enzyme immunoassay kits for measuring low levels of salivary estradiol and testosterone in adolescents and objectively assessed prevalence of blood contamination. METHODS: Endocrine patients provided plasma and saliva for estradiol (females) or testosterone (males) assay. Saliva samples were also tested with a blood contamination kit. RESULTS: Picomolar levels of salivary estradiol in females failed to show any significant correlation with plasma values (r=0.20, p=0.37). The nanomolar levels of salivary testosterone in males showed a strong correlation (r=0.78, p<0.001). A significant number of saliva samples had blood contamination. After exclusion, correlations remained non-significant for estradiol, but strengthened for testosterone (r=0.88, p<0.001). CONCLUSION: The salivary estradiol enzyme immunoassay is not clinically informative at low levels. Users should interpret clinical saliva with caution due to potential blood contamination. Our data supports the utility of the salivary testosterone enzyme immunoassay for monitoring adolescent boys on hormone developmental therapy.

Autoantibodies in movement and psychiatric disorders: updated concepts in detection methods, pathogenicity, and CNS entry.

In recent years, autoantibodies to proteins or receptors expressed on the surface of neurons have been detected in movement and psychiatric disorders. These autoantibodies can assist in better recognition of clinical syndromes and offer novel treatment opportunities via immunotherapies, potentially leading to improved patient outcome. In this review, we describe several autoimmune syndromes associated with movement and psychiatric disorders, including anti-N-methyl-d-aspartate receptor encephalitis, basal ganglia encephalitis, Sydenham chorea, and autoantibody-associated psychosis and schizophrenia. However, rather than focusing on clinical aspects of these diseases, as they have been reviewed in detail elsewhere, we mainly focus on the scientific aspects of the different methodologies for detecting antibodies, with an emphasis on the current gold standard in the field, the cell-based assay, and on issues related to the use of live versus permeabilized cells. We also reflect on the implications associated with the choice of patient serum and cerebrospinal fluid for antibody testing, on the mechanism of antibody entry into the central nervous system through the blood-brain barrier, and the essential issue of antibody pathogenicity.

High-throughput flow cytometry cell-based assay to detect antibodies to N-methyl-D-aspartate receptor or dopamine-2 receptor in human serum.

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders.