Social Opportunity Causes Rapid Transcriptional Changes in the Social Behaviour Network of the Brain in an African Cichlid Fish

Animals constantly integrate external stimuli with their own internal physiological state to make appropriate behavioural decisions. Little is known, however, about where in the brain the salience of these signals is evaluated, or which neural and transcriptional mechanisms link this integration to adaptive behaviours. We used an African cichlid fish Astatotilapia burtoni to test the hypothesis that a new social opportunity activates the conserved \u27social behaviour network\u27 (SBN), a collection of brain nuclei known to regulate social behaviours across vertebrates. We measured mRNA levels of immediate early genes (IEGs) in microdissected brain regions as a proxy for neuronal activation, and discovered that IEGs were higher in all SBN nuclei in males that were given an opportunity to rise in social rank compared to control stable subordinate and dominant individuals. Furthermore, because the presence of sex-steroid receptors is one defining criteria of SBN nuclei, we also tested whether social opportunity or status influenced androgen and oestrogen receptor mRNA levels within these same regions. There were several rapid region-specific changes in receptor mRNA levels induced by social opportunity, most notably in oestrogen receptor subtypes in areas that regulate social aggression and reproduction, suggesting that oestrogenic signalling pathways play an important role in regulating male status. Several receptor mRNA changes occurred in regions with putative homologies to the mammalian septum and extended amygdala, two regions shared by SBN and reward circuits, suggesting an important role in the integration of social salience, stressors, hormonal state and adaptive behaviours. We also demonstrated increases in plasma sex- and stress-steroids at 30 min after a rise in social rank. This rapid endocrine and transcriptional response suggests that the SBN is involved in the integration of social inputs with internal hormonal state to facilitate the transition to dominant status, which ultimately leads to improved fitness for the previously reproductively-suppressed individual. © 2012 British Society for Neuroendocrinology

Racial and Ethnic Disparities in the Pediatric Hodgkin Lymphoma Population.

BACKGROUND: Little is known about the association between race/ethnicity and survival in pediatric Hodgkin lymphoma (HL) patients. In a state-wide pediatric cohort diagnosed with HL, we assessed demographic, disease, and treatment characteristics associated with overall survival (OS). We then attempted to validate these findings and assess disease-specific survival (DSS) in a national Surveillance, Epidemiology, and End Results (SEER) cohort. PROCEDURE: HL patients of 0.1-21 years diagnosed from 1981 to 2010 were evaluated using the Florida Cancer Data System (FCDS). Kaplan-Meier curves estimated OS from 5 to 25 years based on race/ethnicity, treatment, decade of diagnosis, and sex. Multivariate Cox proportional hazard regressions tested independent factors associated with differences in OS. These methods were replicated in the SEER with additional assessment of DSS. RESULTS: A total of 1,778 patients were identified in the FCDS and 6,027 in the SEER. Median diagnosis age was 17 years in both cohorts. In the FCDS, Blacks had worse OS than Whites and Hispanics at 25 years (33% vs. 49.2% vs. 44.7%, respectively; P = 0.0005), and Black race was associated with inferior OS on multivariate regression (hazard ratio [HR]: 1.81, P = 0.0003). In the SEER, Blacks had inferior OS (Blacks 74.2% vs. Whites 82% vs. Hispanics 82%; P = 0.0005) and DSS (85.7% vs. 90.8% vs. 88.1%, respectively; P = 0.0002) at 25 years. Hispanic males had inferior DSS compared to White males (84.8% vs. 90.6%; P = 0.0478), and Hispanic race was a predictor for inferior DSS on multivariate analysis (HR: 1.238; P \u3c 0.0001). CONCLUSIONS: Racial/ethnic disparities persist in the pediatric HL population despite modern treatment; underlying causes of these disparities are complex and need further examination