Widespread negative response elements mediate direct repression by agonist-liganded glucocorticoid receptor.

The glucocorticoid (GC) receptor (GR), when liganded to GC, activates transcription through direct binding to simple (+)GRE DNA binding sequences (DBS). GC-induced direct repression via GR binding to complex "negative" GREs (nGREs) has been reported. However, GR-mediated transrepression was generally ascribed to indirect "tethered" interaction with other DNA-bound factors. We report that GC-induces direct transrepression via the binding of GR to simple DBS (IR nGREs) unrelated to (+)GRE. These DBS act on agonist-liganded GR, promoting the assembly of cis-acting GR-SMRT/NCoR repressing complexes. IR nGREs are present in over 1000 mouse/human ortholog genes, which are repressed by GC in vivo. Thus variations in the levels of a single ligand can coordinately turn genes on or off depending in their response element DBS, allowing an additional level of regulation in GR signaling. This mechanism suits GR signaling remarkably well, given that adrenal secretion of GC fluctuates in a circadian and stress-related fashion.

Nr4a receptors are essential for thymic regulatory T cell development and immune homeostasis.

Regulatory T cells (T(reg) cells) develop from progenitor thymocytes after the engagement of T cell antigen receptors (TCRs) with high-affinity ligands, but the underlying molecular mechanisms are still unclear. Here we show that the Nr4a nuclear receptors, which are encoded by immediate-early genes upregulated by TCR stimulation in thymocytes, have essential roles in T(reg) cell development. Mice that lacked all Nr4a factors could not produce T(reg) cells and died early owing to systemic autoimmunity. Nr4a receptors directly activated the promoter of the gene encoding the transcription factor Foxp3, and forced activation of Nr4a receptors bypassed low-strength TCR signaling to drive the T(reg) cell developmental program. Our results suggest that Nr4a receptors have key roles in determining CD4(+) T cell fates in the thymus and thus contribute to immune homeostasis.

Measuring severe obesity in pediatrics using body mass index-derived metrics from the Centers for Disease Control and Prevention and World Health Organization: a secondary analysis of CANadian Pediatric Weight management Registry (CANPWR) data.

To examine the (i) relationships between various body mass index (BMI)-derived metrics for measuring severe obesity (SO) over time based the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) references and (ii) ability of these metrics to discriminate children and adolescents based on the presence of cardiometabolic risk factors. In this cohort study completed from 2013 to 2021, we examined data from 3- to 18-year-olds enrolled in the CANadian Pediatric Weight management Registry. Anthropometric data were used to create nine BMI-derived metrics based on the CDC and WHO references. Cardiometabolic risk factors were examined, including dysglycemia, dyslipidemia, and elevated blood pressure. Analyses included Pearson correlations, intraclass correlation coefficients (ICC), and receiver operator characteristic area-under-the-curve (ROC AUC). Our sample included 1,288 participants (n = 666 [52%] girls; n = 874 [68%] white). The prevalence of SO varied from 60-67%, depending on the definition. Most BMI-derived metrics were positively and significantly related to one another (r = 0.45-1.00); ICCs revealed high tracking (0.90-0.94). ROC AUC analyses showed CDC and WHO metrics had a modest ability to discriminate the presence of cardiometabolic risk factors, which improved slightly with increasing numbers of risk factors. Overall, most BMI-derived metrics rated poorly in identifying presence of cardiometabolic risk factors.    Conclusion: CDC BMI percent of the 95th percentile and WHO BMIz performed similarly as measures of SO, although neither showed particularly impressive discrimination. They appear to be interchangeable in clinical care and research in pediatrics, but there is a need for a universal standard. WHO BMIz may be useful for clinicians and researchers from countries that recommend using the WHO growth reference. What is Known: • Severe obesity in pediatrics is a global health issue. • Few reports have evaluated body mass index (BMI)-derived metrics based on the World Health Organization growth reference. What is New: • Our analyses showed that the Centers for Disease Control and Prevention BMI percent of the 95th percentile and World Health Organization (WHO) BMI z-score (BMIz) performed similarly as measures of severe obesity in pediatrics. • WHO BMIz should be a useful metric to measure severe obesity for clinicians and researchers from countries that recommend using the WHO growth reference.

Myod1 and GR coordinate myofiber-specific transcriptional enhancers.

Skeletal muscle is a dynamic tissue the size of which can be remodeled through the concerted actions of various cues. Here, we investigated the skeletal muscle transcriptional program and identified key tissue-specific regulatory genetic elements. Our results show that Myod1 is bound to numerous skeletal muscle enhancers in collaboration with the glucocorticoid receptor (GR) to control gene expression. Remarkably, transcriptional activation controlled by these factors occurs through direct contacts with the promoter region of target genes, via the CpG-bound transcription factor Nrf1, and the formation of Ctcf-anchored chromatin loops, in a myofiber-specific manner. Moreover, we demonstrate that GR negatively controls muscle mass and strength in mice by down-regulating anabolic pathways. Taken together, our data establish Myod1, GR and Nrf1 as key players of muscle-specific enhancer-promoter communication that orchestrate myofiber size regulation.

An affirming approach to caring for transgender and gender-diverse youth.

Increasing numbers of youth identify as transgender or gender-diverse (TGD). Many paediatricians and primary care providers (PCPs) will encounter this population in their practice, either for gender-related care or general health needs. This statement is intended as a resource to guide paediatricians and PCPs in implementing an affirming approach to routine health care provision for all youth. Furthermore, it presents information to assist providers in responding to requests for counselling from TGD youth and their families around potential options for medical transition, and in making referrals to specialized services, if desired and relevant. Finally, as demand for gender-affirming care is anticipated to continue to increase, some health care providers (HCPs) may wish to develop the knowledge and skills required to initiate adolescents on hormone-blocking agents and gender-affirming hormones. This document is not intended to be a clinical practice guideline, but will provide foundational information regarding these potential components of gender-affirming care, recognizing that the needs and goals of individual adolescents may or may not include such interventions. Additional resources relevant to developing the expertise required to provide gender-affirming interventions will also be identified.

Une approche d'affirmation pour les soins aux jeunes transgenres et de diverses identités de genre.

Un nombre croissant de jeunes s'identifient comme transgenres ou de diverses identités de genre. De nombreux pédiatres et dispensateurs de soins de première ligne accueilleront cette population dans leur pratique, dans le cadre de soins liés au genre ou de soins de santé généraux. Le présent document de principes se veut une ressource pour orienter les pédiatres et les dispensateurs de soins de première ligne à adopter une approche d'affirmation pour la prestation des soins réguliers à tous les jeunes. De plus, il contient de l'information visant à aider les dispensateurs à répondre aux demandes de conseils des jeunes transgenres et de diverses identités de genre et de leur famille au sujet des possibilités de transition médicale et d'orientation vers des services spécialisés s'ils le désirent et le jugent pertinent. Enfin, on anticipe que la demande de soins d'affirmation de genre continue d'augmenter, et certains dispensateurs de soins peuvent souhaiter acquérir les connaissances et les habiletés nécessaires pour amorcer les inhibiteurs d'hormones et les hormones d'affirmation de genre chez les adolescents. Le présent document ne contient pas de directives cliniques, mais de l'information fondamentale au sujet des divers éléments possibles des soins d'affirmation de genre, tout en reconnaissant que les besoins et les objectifs d'adolescents particuliers n'incluent pas automatiquement de telles interventions. D'autres ressources permettant d'acquérir les compétences nécessaires pour offrir des interventions d'affirmation de genre sont également proposées.

Tyrosine hydroxylase conditional KO mice reveal peripheral tissue-dependent differences in dopamine biosynthetic pathways.

Dopamine (DA) exerts well-known functions in the brain as a neurotransmitter. In addition, it plays important physiological roles in peripheral organs, but it is largely unknown how and where peripheral DA is synthesized and regulated. Catecholamines in peripheral tissues are either produced within the tissue itself and/or derived from sympathetic neurons, which release neurotransmitters for uptake by peripheral tissues. To evaluate DA-producing ability of each peripheral tissue, we generated conditional KO mice (cKO mice) in which the tyrosine hydroxylase (TH) gene is ablated in the sympathoadrenal system, thus eliminating sympathetic neurons as a DA source. We then examined the alterations in the noradrenaline (NA), DA, and 3,4-dihydroxyphenylalanine (DOPA) contents in peripheral organs and performed immunohistochemical analyses of TH-expressing cells. In the heart and pancreas of cKO mice, both the TH protein and NA levels were significantly decreased, and the DA contents were decreased in parallel with NA contents, indicating that the DA supply originated from sympathetic neurons. We found TH-immunoreactive cells in the stomach and lung, where the TH protein showed a decreasing trend, but the DA levels were not decreased in cKO mice. Moreover, we found a significant correlation between the DA content in the kidney and the plasma DOPA concentration, suggesting that the kidney takes up DOPA from blood to make DA. The aforementioned data unravel differences in the DA biosynthetic pathway among tissues and support the role of sympathetic neurons as a DA supplier.

Surgical Outcomes in Patients With Malignant Small Bowel Obstruction: A National Cohort Study.

OBJECTIVE: The study objectives were to characterize surgical outcomes for malignant small bowel obstruction (MaSBO) as compared to other small bowel obstructions (SBO) and to develop a prediction model for postoperative mortality for MaSBO. SUMMARY BACKGROUND DATA: MaSBO is a morbid complication of advanced cancers for which the optimal management remains undefined. METHODS: Patients who underwent surgery for MaSBO or SBO were identified from the National Surgical Quality Improvement Program (2005-2017). Outcomes [30-day morbidity, unplanned readmissions, mortality, postoperative length of stay (LOS)] were compared between propensity score-matched MaSBO and SBO patients. An internally validated prediction model for mortality in MaSBO patients was developed. RESULTS: Of 46,706 patients, 1612 (3.5%) had MaSBO. Although MaSBO patients were younger than those with SBO (median 63 vs 65 years, P < 0.001), they were otherwise more clinically complex, including a higher proportion with recent weight loss (22.0% vs 4.0%, P < 0.001), severe hypoalbuminemia (18.6% vs 5.2%, P < 0.001), and cytopenias. After matching (N = 1609/group), MaSBO was associated with increased morbidity [odds ratio (OR) 1.2, P = 0.004], but not readmission (OR 1.1, P = 0.48) or LOS (incidence rate ratio 1.0, P = 0.14). The odds of mortality were significantly higher for MaSBO than SBO (OR 3.3, P < 0.001). A risk-score model predicted postoperative mortality for MaSBO with an optimism-adjusted Brier score of 0.114 and area under the curve of 0.735. Patients in the highest-risk category (11.5% of MaSBO population) had a predicted mortality rate of 39.4%. CONCLUSION: Surgery for MaSBO is associated with substantial morbidity and mortality, necessitating careful patient evaluation before operative intervention.

Long-term hypogonadism diminishes the neuroprotective effects of dietary genistein in young adult ovariectomized rats after transient focal ischemia.

Increasing age disproportionately increases the risk of stroke among women compared to men of similar age, especially after menopause. One of the reasons for this observation is a sharp drop in circulating estrogens. However, the timing of initiation of estrogen replacement after menopause is associated with mixed beneficial and detrimental effects, hence contributing to widespread mistrust of estrogen use. Agents including soy isoflavones are being assessed as viable alternatives to estrogen therapy. In this study, we hypothesized that the neuroprotective effects of genistein, a soy isoflavone are less sensitive to the length of hypogonadism in young adult ovariectomized rats following cerebral ischemia. We expected that long-term hypogonadism will worsen motor and cognitive function, increase post-stroke inflammation with no effect on the neuroprotection of genistein. We compared the effect of treatment with dietary genistein (GEN) on short-term (2 weeks) and long-term hypogonadism (12 weeks) in young adult ovariectomized Sprague-Dawley rats on sensorimotor function, cognition and inflammation after focal ischemia. Dorsal Silastic implant of 17ß-estradiol (E2) was used as a control for hormone therapy. Long-term hypogonadism stroked rats performed worse than the short-term hypogonadism stroked rats on the motor and cognitive function tests. GEN did not improve neurological assessment and motor learning after either short-term or long-term hypogonadism. GEN improved cognitive flexibility after short-term hypogonadism but not after the long-term. Both GEN and E2 reduced tissue loss after short-term hypogonadism and reduced GFAP expression at the contralateral side of ischemia after long-term hypogonadism. The length of hypogonadism may differentially influence the neuroprotective effects of both GEN and E2 on the motor and cognitive functions in young adult rats.

Do Clinical Data from Transgender Adolescents Support the Phenomenon of "Rapid Onset Gender Dysphoria"?

Although emergence of gender dysphoria at puberty is long established, a distinct pathway of rapid onset gender dysphoria was recently hypothesized based on parental data. Using adolescent clinical data, we tested a series of associations that would be consistent with this pathway, however, our results did not support the rapid onset gender dysphoria hypothesis.