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Human aging is associated with skeletal muscle atrophy and functional impairment (sarcopenia). Multiple lines of evidence suggest that mitochondrial dysfunction is a major contributor to sarcopenia. We evaluated whether healthy aging was associated with a transcriptional profile reflecting mitochondrial impairment and whether resistance exercise could reverse this signature to that approximating a younger physiological age. Skeletal muscle biopsies from healthy older (N = 25) and younger (N = 26) adult men and women were compared using gene expression profiling, and a subset of these were related to measurements of muscle strength. 14 of the older adults had muscle samples taken before and after a six-month resistance exercise-training program. Before exercise training, older adults were 59% weaker than younger, but after six months of training in older adults, strength improved significantly (P<0.001) such that they were only 38% lower than young adults. As a consequence of age, we found 596 genes differentially expressed using a false discovery rate cut-off of 5%. Prior to the exercise training, the transcriptome profile showed a dramatic enrichment of genes associated with mitochondrial function with age. However, following exercise training the transcriptional signature of aging was markedly reversed back to that of younger levels for most genes that were affected by both age and exercise. We conclude that healthy older adults show evidence of mitochondrial impairment and muscle weakness, but that this can be partially reversed at the phenotypic level, and substantially reversed at the transcriptome level, following six months of resistance exercise training.

In this study we used functional magnetic resonance imaging to investigate age-related changes in large-scale brain functional networks during memory encoding and recognition in 12 younger and 16 older adults. For each participant, functional brain networks were constructed by computing temporal correlation matrices of 90 brain regions and analyzed using graph theoretical approaches. We found the age-related changes mainly in the long-range connections with widespread reductions associated with aging in the fronto-temporal and temporo-parietal regions, and a few age-related increases in the posterior parietal regions. Graph theoretical analysis revealed that the older adults had longer path lengths linking different regions in the functional brain networks as compared to the younger adults. Further analysis indicated that the increases in shortest path length in the networks were combined with the loss of long-range connections. Finally, we showed that for older adults, frontal areas played reduced roles in the network (reduced regional centrality), whereas several default-mode regions played increased roles relative to younger subjects (increased regional centrality). Together, our results suggest that normal aging is associated with disruption of large-scale brain systems during the performance of memory tasks, which provides novel insights into the understanding of age-related decline in multiple cognitive functions.

AbstractThis chapter focuses on cis and trans sex workers’ experiences with law enforcement, and how various regimes of regulating sex work including full and partial criminalisation, legalisation, and decriminalisation shape the human rights and the work environments of sex workers globally including access to occupational health and safety, police protection, and legal recourse. Criminalisation and policing of sex work constitute forms of structural violence that perpetuate and exacerbate experiences of interpersonal violence and negative health outcomes among sex workers globally. Country spotlights from the global North and South provide examples of different regimes of regulation and draw attention to how laws and regulations interact with specific work environments in various settings to shape sex workers’ lived experiences of health, safety, and human rights. This chapter highlights how various approaches to criminalising and policing sex work undermine sex workers’ safety, health and human rights, including violence and poor health and concludes with an evidence-based call for the decriminalisation of sex work globally.

Abstract Biological differences between males and females are found at multiple levels. However, females have too often been under-represented in behavioral neuroscience research, which has stymied the study of potential sex differences in neurobiology and behavior. This review focuses on the study of sex differences in the neurobiology of social behavior, memory, emotions, and recovery from brain injury, with particular emphasis on the role of estrogens in regulating forebrain function. This work, presented by the authors at the 2016 meeting of the International Behavioral Neuroscience Society, emphasizes varying approaches from several mammalian species in which sex differences have not only been documented, but also become the focus of efforts to understand the mechanistic basis underlying them. This information may provide readers with useful experimental tools to successfully address recently introduced regulations by granting agencies that either require (e.g. the National Institutes of Health in the United States and the Canadian Institutes of Health Research in Canada) or recommend (e.g. Horizon 2020 in Europe) the inclusion of both sexes in biomedical research.

ABSTRACTFollowing sensory deprivation, primary somatosensory and visual cortices undergo crossmodal plasticity, which subserves the remaining modalities. However, controversy remains regarding the neuroplastic potential of primary auditory cortex (A1). To examine this, we identified cortical and thalamic projections to A1 in hearing cats and those with early‐ and late‐onset deafness. Following early deafness, inputs from second auditory cortex (A2) are amplified, whereas the number originating in the dorsal zone (DZ) decreases. In addition, inputs from the dorsal medial geniculate nucleus (dMGN) increase, whereas those from the ventral division (vMGN) are reduced. In late‐deaf cats, projections from the anterior auditory field (AAF) are amplified, whereas those from the DZ decrease. Additionally, in a subset of early‐ and late‐deaf cats, area 17 and the lateral posterior nucleus (LP) of the visual thalamus project concurrently to A1. These results demonstrate that patterns of projections to A1 are modified following deafness, with statistically significant changes occurring within the auditory thalamus and some cortical areas. Moreover, we provide anatomical evidence for small‐scale crossmodal changes in projections to A1 that differ between early‐ and late‐onset deaf animals, suggesting that potential crossmodal activation of primary auditory cortex differs depending on the age of deafness onset. J. Comp. Neurol. 523:2297–2320, 2015. © 2015 Wiley Periodicals, Inc.

Background Rapid reviews are a form of knowledge synthesis in which components of the systematic review process are simplified or omitted to produce information in a timely manner. Although numerous centers are conducting rapid reviews internationally, few studies have examined the methodological characteristics of rapid reviews. We aimed to examine articles, books, and reports that evaluated, compared, used or described rapid reviews or methods through a scoping review. Methods MEDLINE, EMBASE, the Cochrane Library, internet websites of rapid review producers, and reference lists were searched to identify articles for inclusion. Two reviewers independently screened literature search results and abstracted data from included studies. Descriptive analysis was conducted. Results We included 100 articles plus one companion report that were published between 1997 and 2013. The studies were categorized as 84 application papers, seven development papers, six impact papers, and four comparison papers (one was included in two categories). The rapid reviews were conducted between 1 and 12 months, predominantly in Europe (58 %) and North America (20 %). The included studies failed to report 6 % to 73 % of the specific systematic review steps examined. Fifty unique rapid review methods were identified; 16 methods occurred more than once. Streamlined methods that were used in the 82 rapid reviews included limiting the literature search to published literature (24 %) or one database (2 %), limiting inclusion criteria by date (68 %) or language (49 %), having one person screen and another verify or screen excluded studies (6 %), having one person abstract data and another verify (23 %), not conducting risk of bias/quality appraisal (7 %) or having only one reviewer conduct the quality appraisal (7 %), and presenting results as a narrative summary (78 %). Four case studies were identified that compared the results of rapid reviews to systematic reviews. Three studies found that the conclusions between rapid reviews and systematic reviews were congruent. Conclusions Numerous rapid review approaches were identified and few were used consistently in the literature. Poor quality of reporting was observed. A prospective study comparing the results from rapid reviews to those obtained through systematic reviews is warranted. Electronic supplementary material The online version of this article (doi:10.1186/s12916-015-0465-6) contains supplementary material, which is available to authorized users.

Different places may share common features, but are coded by distinct populations of CA3 neurons in the hippocampus. Here we show that chemical or genetic suppression of adult neurogenesis in the hippocampus impairs this population-based coding of similar (but not dissimilar) contexts. These data provide a neural basis for impaired spatial discrimination following ablation of adult neurogenesis, and support the proposal that adult neurogenesis regulates the efficiency of a pattern separation process in the hippocampus.

This article examines relationships between perceived ethnic discrimination, social exclusion, psychosocial functioning, and academic performance among newcomer immigrant children from the People's Republic of China, Hong Kong, and the Philippines using a subsample from the New Canadian Children and Youth Study of children aged 11-13 years (1,053) living in Montreal, Toronto, Vancouver, and the Prairies. Bivariate analysis showed that 25% of children reported being treated unfairly by peers and 14% by teachers because of who they are. Regression analyses revealed that perceived ethnic discrimination by peers and teachers was negatively related to children's sense of social competence in peer relationships. Children's self-esteem and sense of academic competence were negatively related to perceived discrimination by teachers. One in 5 children reported feeling like an outsider, with boys revealing higher levels of psychological isolation than girls. More than 1 in 10 were socially isolated and reported never participating in organized activities. This may reflect economic exclusion, as over one third of respondents belonged to families living below the Canadian Income Adequacy Measure. Psychological isolation, social isolation, and economic exclusion were significant predictors of children's sense of academic competence and actual academic grades. Variations exist across age, sex, ethnicity, family structure, parental education, region of settlement, and length of time since arrival in Canada.