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.

Dietary genistein and 17ß-estradiol implants differentially influence locomotor and cognitive functions following transient focal ischemia in middle-aged ovariectomized rats at different lengths of estrogen deprivation.

Genistein possesses estrogenic activity and has been considered a potential replacement for estrogen replacement therapy after menopause. In the current study, we investigated the neuroprotective effects of dietary genistein at varied lengths of estrogen deprivation in middle-aged ovariectomized Sprague-Dawley rats under ischemic conditions. Two weeks of treatment with dietary genistein at 42 mg/kg but not 17ß-estradiol implants improved cognitive flexibility (Morris water maze test) after short-term estrogen deprivation (2 weeks) but not long-term estrogen deprivation (12 weeks). 17ß-estradiol implants but not dietary genistein improved locomotor asymmetry (cylinder test) after long-term but not short-term estrogen deprivation. Dietary genistein but not 17ß-estradiol implant improved early phase motor learning (rotarod test) after long-term estrogen deprivation. Neither 17ß-estradiol implant nor dietary genistein reduced infarct size after either short-term or long-term estrogen deprivation. Genistein, however, reduced ionized calcium-binding adaptor molecule-1 (Iba1) expression, a marker of brain inflammation, at the ipsilateral side of stroke injury after short-term but not long-term estrogen deprivation. This study suggests that the neuroprotective effects of dietary genistein on motor and cognitive functions are distinctly influenced by the length of estrogen deprivation following focal ischemia. SIGNIFICANCE: There is an increasing postmenopausal population opting for homeopathic medicines for the management of menopausal symptoms due to the perceived distrust in estrogen use as hormone replacement. Basic and clinical studies support the notion that early, but not delayed, hormone replacement after menopause is beneficial. Furthermore, evidence suggests that delaying hormone replacement augments the detrimental, rather than the beneficial effects of estrogens. Because of the active consideration of soy isoflavones including genistein as alternatives to estrogen replacement, it is necessary to understand the ramifications of soy isoflavones use when their administration is begun at various times after menopause.

Vitamin D Analogs Bearing C-20 Modifications Stabilize the Agonistic Conformation of Non-Responsive Vitamin D Receptor Variants.

The Vitamin D receptor (VDR) plays a key role in calcium homeostasis, as well as in cell proliferation and differentiation. Among the large number of VDR ligands that have been developed, we have previously shown that BXL-62 and Gemini-72, two C-20-modified vitamin D analogs are highly potent VDR agonists. In this study, we show that both VDR ligands restore the transcriptional activities of VDR variants unresponsive to the natural ligand and identified in patients with rickets. The elucidated mechanisms of action underlying the activities of these C-20-modified analogs emphasize the mutual adaptation of the ligand and the VDR ligand-binding pocket.

Isolated diastolic high blood pressure: a distinct clinical phenotype in US children.

BACKGROUND: Screening studies have shown that 0.7-4.5% of generally healthy children have isolated diastolic high BP. We therefore studied the characteristics of children with diastolic BP in the elevated and hypertensive ranges according to current guidelines in US children from the National Health and Nutrition Examination Survey (NHANES, 1999-2016). METHODS: We studied 17,362 children (8-18 years) with BP measured by sphygmomanometry. High BP was categorized as isolated systolic (iSH), isolated diastolic (iDH), or Mixed. RESULTS: Overall, 86.0% (95% CI = 85.0-87.0) of the population had normal BP, 8.7% (8.0-9.3) elevated BP, 4.9% (4.4-5.5) Stage 1, and 0.4% (0.4-0.6) Stage 2. Moreover, 11.1% (10.3-12.0) had iSH, 1.9% (1.5-2.2) iDH, and 1.0% (0.8-1.2) Mixed. Children with iDH were more likely to be female, younger, white, and leaner than those with iSH, with lower rates of overweight/obesity. iDH was generally between normals and iSH. Resting heart rate was significantly higher in iDH even after adjustment for known covariates. CONCLUSIONS: Children with iDH may have a distinct clinical picture. A leaner habitus and higher resting heart rate may reflect differences in underlying pathophysiology. Longitudinal follow-up studies are needed to better define the pathogenesis, progression, and long-term prognosis in iDH. IMPACT: Using gold-standard auscultation and 2017 guidelines, isolated diastolic high BP (iDH) is found in 1.9% (95% CI 1.5-2.2) of American children; these children are younger, leaner, more female, and have fewer cardiometabolic risks. Resting heart rate is significantly higher in iDH compared to both normals and iSH even after adjustments for known covariates. Autonomic hyperactivity in iDH may speak to both etiology and therapeutic approaches. iDH appears to be a distinct clinical phenotype characterized by differences in anthropometric measures, sex, age, and resting heart rate. Follow-up studies are clearly needed to clarify its pathogenesis, progression, and prognosis.

Prevalence of high blood pressure among Canadian Children: 2017 American Academy of Pediatrics guidelines with the Canadian Health Measures Survey.

BACKGROUND: We assess the impact of the 2017 American Academy of Pediatrics (AAP) guidelines on the prevalence of high blood pressure (BP) in generally healthy Canadian children and identify risk factors associated with high BP (elevated, stage 1, or stage 2 at a single visit). METHODS: A cohort of 7,387 children aged 6 to 18 years in the Canadian Health Measures Survey (CHMS, 2007 to 2015) had BPTru oscillometry with centiles and stages assigned using both the 2017 AAP guidelines and the 2004 Fourth Report from the National Institute of Health/National Heart Lung and Blood Institute (NIH/NHLBI). RESULTS: Although both shifted upwards significantly, mean population systolic BP and diastolic BP percentiles are now 24.2 (95% confidence interval: 23.3 to 25.2) and 46.4 (45.3 to 47.6). As a result, the population prevalence of high BP increased from 4.5% (3.9 to 5.2, NIH/NHLBI) to 5.8% (5.0 to 6.6, AAP), less than in US children measured by auscultation (14.2%, 13.4 to 15.0). Children with high BP were more likely to be overweight/obese, to be exposed to prenatal/household smoking, and to have hypertriglyceridemia, without differences in dietary salt, infant breastfeeding, neonatal hospitalizations, or exercise frequency. CONCLUSION: The 2017 AAP guidelines increase the prevalence of high BP in Canadian children; Canadian prevalence appears lower than in the USA. This may reflect differences in measurement methods or in the prevalence of childhood overweight/obesity between countries, that is, 31.1% (28.9 to 33.3) versus 40.6% (39.5 to 42.0), respectively. Those with high BP were more likely to have other cardiac risk factors, including overweight/obesity, prenatal/household smoking exposure, and hypertriglyceridemia.

Are there alternatives to over-the-counter diabetes-care glucose-gels for transitional neonatal hypoglycemia?

Transitional neonatal hypoglycemia is common in at-risk well newborns, requires immediate attention, interferes with breastfeeding, and frequently results in separation of mothers from their babies. Breastfeeding shortly after birth and screening at-risk newborns at 2 hours of age is standard practice in Canada. In the Sugar Babies Trial, a custom-made 40% glucose-gel massaged to the buccal mucosa in at-risk infants decreased intravenous glucose treatment, but not neonatal intensive care unit admission. It increased the rate of full breastfeeding after discharge but experts suggest that additional evidence is needed. Further, commercially available neonatal glucose-gels do not exist, so practitioners around the world have started using diabetes-care products, which do not meet standards for use in newborns. Here, we provide a condensed summary of the topic and of management alternatives.

Chronic Testosterone Deprivation Sensitizes the Middle-Aged Rat Brain to Damaging Effects of Testosterone Replacement.

INTRODUCTION: An increasing number of middle-aged men are being screened for low testosterone levels and the number of prescriptions for various forms of testosterone replacement therapy (TRT) has increased dramatically over the last 10 years. However, the safety of TRT has come into question with some studies suggesting increased morbidity and mortality. OBJECTIVE: Because the benefits of estrogen replacement in postmenopausal women and ovariectomized rodents are lost if there is an extended delay between estrogen loss and replacement, we hypothesized that TRT may also be sensitive to delayed replacement. METHODS: We compared the effects of testosterone replacement after short-term (2 weeks) and long-term testosterone deprivation (LTTD; 10 weeks) in middle-aged male rats on cerebral ischemia, oxidative stress, and cognitive function. We hypothesized that LTTD would increase oxidative stress levels and abrogate the beneficial effects of TRT. RESULTS: Hypogonadism itself and TRT after short-term castration did not affect stroke outcome compared to intact rats. However, after long-term hypogonadism in middle-aged male Fischer 344 rats, TRT exacerbated the detrimental behavioral effects of experimental focal cerebral ischemia, whereas this detrimental effect was prevented by administration of the free-radical scavenger tempol, suggesting that TRT exacerbates oxidative stress. In contrast, TRT improved cognitive performance in non-stroked rats regardless of the length of hypogonadism. In the Morris water maze, peripheral oxidative stress was highly associated with decreased cognitive ability. CONCLUSIONS: Taken together, these data suggest that TRT after long-term hypogonadism can exacerbate functional recovery after focal cerebral ischemia, but in the absence of injury can enhance cognition. Both of these effects are modulated by oxidative stress levels.

Fluid management in children with diabetic ketoacidosis.

QUESTION: Previous research has indicated that rapid rehydration in children with type 1 diabetes who present with diabetic ketoacidosis could result in cerebral edema. I have been treating patients with diabetic ketoacidosis with gradual fluid replacement. With the risk of cerebral injury in these patients, should I continue management with slow fluid rehydration? ANSWER: Recent research has shown that neither fluid infusion rate nor sodium chloride concentration increases risk of cerebral injury. However, it is possible for subtle brain injury to occur during treatment, regardless of the fluid administration strategy. The 2018 International Society for Pediatric and Adolescent Diabetes guidelines have been updated in light of this research.

Exome Sequencing and the Management of Neurometabolic Disorders.

BACKGROUND: Whole-exome sequencing has transformed gene discovery and diagnosis in rare diseases. Translation into disease-modifying treatments is challenging, particularly for intellectual developmental disorder. However, the exception is inborn errors of metabolism, since many of these disorders are responsive to therapy that targets pathophysiological features at the molecular or cellular level. METHODS: To uncover the genetic basis of potentially treatable inborn errors of metabolism, we combined deep clinical phenotyping (the comprehensive characterization of the discrete components of a patient's clinical and biochemical phenotype) with whole-exome sequencing analysis through a semiautomated bioinformatics pipeline in consecutively enrolled patients with intellectual developmental disorder and unexplained metabolic phenotypes. RESULTS: We performed whole-exome sequencing on samples obtained from 47 probands. Of these patients, 6 were excluded, including 1 who withdrew from the study. The remaining 41 probands had been born to predominantly nonconsanguineous parents of European descent. In 37 probands, we identified variants in 2 genes newly implicated in disease, 9 candidate genes, 22 known genes with newly identified phenotypes, and 9 genes with expected phenotypes; in most of the genes, the variants were classified as either pathogenic or probably pathogenic. Complex phenotypes of patients in five families were explained by coexisting monogenic conditions. We obtained a diagnosis in 28 of 41 probands (68%) who were evaluated. A test of a targeted intervention was performed in 18 patients (44%). CONCLUSIONS: Deep phenotyping and whole-exome sequencing in 41 probands with intellectual developmental disorder and unexplained metabolic abnormalities led to a diagnosis in 68%, the identification of 11 candidate genes newly implicated in neurometabolic disease, and a change in treatment beyond genetic counseling in 44%. (Funded by BC Children's Hospital Foundation and others.).

Practice Patterns and Prognostic Value of Sentinel Lymph Node Biopsy for Thick Melanoma: A National Cancer Database Study.

BACKGROUND: Sentinel lymph node biopsy (SLNB) has been somewhat controversial for patients with a diagnosis of thick (> 4 mm) melanoma. This study aimed to characterize the national practice pattern in performing SLNB for this patient population and to determine the predictors and prognostic value of nodal positivity using population-level data. METHODS: Patients with a diagnosis of clinically node-negative, thick melanoma (2010-2015) were identified using the National Cancer Database. Factors associated with performing regional nodal evaluation were characterized. Predictors of nodal positivity were determined using multivariable logistic regression. Overall survival (OS) was estimated using standard statistical methods. RESULTS: Of 9847 study patients, 7513 (76.3%) underwent SLNB. The patients who underwent nodal evaluation were younger (median age, 66 vs 81 years; P < 0.001), less likely to have comorbid conditions (19.6% vs 26.0%; P < 0.001), more often privately insured (40.4% vs 16.4%; P < 0.001), and more frequently treated at an academic center (49.5% vs 43.9%; P < 0.001). Among those who underwent nodal evaluation, 25.5% had metastatic nodes. Multivariable regression identified age, Charlson-Deyo score, primary location, ulceration, mitoses, vertical growth phase, and lymphovascular invasion as independent predictors of nodal positivity, but with only moderate predictive accuracy (optimism-adjusted area under the curve, 0.684). Furthermore, compared with node negativity, node positivity was significantly associated with decreased OS (hazard ratio, 2.05; P < 0.001). CONCLUSION: Although nodal status provides important prognostic information, at a national level, nearly one fourth of patients with clinically node-negative, thick melanoma do not undergo SLNB. Appropriate pathologic staging would allow these high-risk patients to be candidates for effective adjuvant therapy.

The Nuclear Receptor Nr4a1 Acts as a Microglia Rheostat and Serves as a Therapeutic Target in Autoimmune-Driven Central Nervous System Inflammation.

Microglia cells fulfill key homeostatic functions and essentially contribute to host defense within the CNS. Altered activation of microglia, in turn, has been implicated in neuroinflammatory and neurodegenerative diseases. In this study, we identify the nuclear receptor (NR) Nr4a1 as key rheostat controlling the activation threshold and polarization of microglia. In steady-state microglia, ubiquitous neuronal-derived stress signals such as ATP induced expression of this NR, which contributed to the maintenance of a resting and noninflammatory microglia phenotype. Global and microglia-specific deletion of Nr4a1 triggered the spontaneous and overwhelming activation of microglia and resulted in increased cytokine and NO production as well as in an accelerated and exacerbated form of experimental autoimmune encephalomyelitis. Ligand-induced activation of Nr4a1 accordingly ameliorated the course of this disease. Our current data thus identify Nr4a1 as regulator of microglia activation and potentially new target for the treatment of inflammatory CNS diseases such as multiple sclerosis.