Hippocampal and parahippocampal volumes vary by sex and traumatic life events in children

BackgroundChildhood trauma is reliably associated with smaller hippocampal volume in adults; however, this finding has not been shown in children, and even less is known about how sex and trauma interact to affect limbic structural development in children.MethodsTypically developing children aged 9 to 15 years who completed a trauma history questionnaire and structural T₁-weighted MRI were included in this study (n = 172; 85 female, 87 male). All children who reported 4 or more traumas (n = 36) composed the high trauma group, and all children who reported 3 or fewer traumas (n = 136) composed the low trauma group. Using multivariate analysis of covariance, we compared FreeSurfer-derived structural MRI volumes (normalized by total intracranial volume) of the amygdalar, hippocampal and parahippocampal regions by sex and trauma level, controlling for age and study site.ResultsWe found a significant sex × trauma interaction, such that girls with high trauma had greater volumes than boys with high trauma. Follow-up analyses indicated significantly increased volumes for girls and generally decreased volumes for boys, specifically in the hippocampal and parahippocampal regions for the high trauma group; we observed no sex differences in the low trauma group. We noted no interaction effect for the amygdalae.LimitationsWe assessed a community sample and did not include a clinical sample. We did not collect data about the ages at which children experienced trauma.ConclusionResults revealed that psychological trauma affects brain development differently in girls and boys. These findings need to be followed longitudinally to elucidate how structural differences progress and contribute to well-known sex disparities in psychopathology.     

Climate Change,Health, and Communication: A Primer

Climate change is one of the most serious and pervasive challenges facing us today. Our changing climate has implications not only for the ecosystems upon which we depend, but also for human health. Health communication scholars are well-positioned to aid in the mitigation of and response to climate change and its health effects. To help theorists, researchers, and practitioners engage in these efforts, this primer explains relevant issues and vocabulary associated with climate change and its impacts on health. First, this primer provides an overview of climate change, its causes and consequences, and its impacts on health. Then, the primer describes ways to decrease impacts and identifies roles for health communication scholars in efforts to address climate change and its health effects.     

Quality of Life Impacts of Bright Light Treatment,Fluoxetine, and the Combination in Patients with Nonseasonal Major Depressive Disorder: A Randomized Clinical Trial

Objective:Bright light therapy is increasingly recommended (alone or in combination with antidepressant medication) to treat symptoms of nonseasonal major depressive disorder (MDD). However, little is known about its impacts on quality of life (QoL), a holistic, patient-valued outcome.Methods:This study utilizes secondary outcome data from an 8-week randomized, controlled, double blind trial comparing light monotherapy (n = 32), fluoxetine monotherapy (n = 30), and the combination of these (n = 27) to placebo (n = 30). QoL was assessed using the Quality of Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF). Treatment-related differences in QoL improvements were assessed using a repeated measures analysis of variance. The influence of potential predictors of QoL (demographic variables and change in depressive symptoms) were investigated via hierarchical linear regression.Results:Q-LES-Q-SF scores significantly improved across all treatment conditions; however, no significant differences were observed between treatment arms. QoL remained poor relative to community norms by the end of the trial period: Across conditions, 70.6% of participants had significantly impaired QoL at the 8-week assessment. Reduction in depressive scores was a significant predictor of improved QoL, with the final model accounting for 54% of variance in QoL change scores.Conclusion:The findings of this study emphasize that improvement in QoL and reduction in depressive symptoms in MDD, while related, cannot be taken to be synonymous. Adjunctive therapies may be required to address unmet QoL needs in patients with MDD receiving antidepressant or light therapies. Further research is required to explore additional predictors of QoL in order to better refine treatments for MDD.     

The Ribosomal S10 Protein Is a General Target for Decreased Tigecycline Susceptibility

Tigecycline is a translational inhibitor with efficacy against a wide range of pathogens. Using experimental evolution, we adapted Acinetobacter baumannii, Enterococcus faecium, Escherichia coli, and Staphylococcus aureus to growth in elevated tigecycline concentrations. At the end of adaptation, 35 out of 47 replicate populations had clones with a mutation in rpsJ, the gene that encodes the ribosomal S10 protein. To validate the role of mutations in rpsJ in conferring tigecycline resistance, we showed that mutation of rpsJ alone in Enterococcus faecalis was sufficient to increase the tigecycline MIC to the clinical breakpoint of 0.5 μg/ml. Importantly, we also report the first identification of rpsJ mutations associated with decreased tigecycline susceptibility in A. baumannii, E. coli, and S. aureus. The identified S10 mutations across both Gram-positive and -negative species cluster in the vertex of an extended loop that is located near the tigecycline-binding pocket within the 16S rRNA. These data indicate that S10 is a general target of tigecycline adaptation and a relevant marker for detecting reduced susceptibility in both Gram-positive and -negative pathogens.