Mycobacteriophages are viruses that infect mycobacterial hosts such as Mycobacterium smegmatis and Mycobacterium tuberculosis. All mycobacteriophages characterized to date are dsDNA tailed phages, and have either siphoviral or myoviral morphotypes. However, their genetic diversity is considerable, and although sixty-two genomes have been sequenced and comparatively analyzed, these likely represent only a small portion of the diversity of the mycobacteriophage population at large. Here we report the isolation, sequencing and comparative genomic analysis of 18 new mycobacteriophages isolated from geographically distinct locations within the United States. Although no clear correlation between location and genome type can be discerned, these genomes expand our knowledge of mycobacteriophage diversity and enhance our understanding of the roles of mobile elements in viral evolution. Expansion of the number of mycobacteriophages grouped within Cluster A provides insights into the basis of immune specificity in these temperate phages, and we also describe a novel example of apparent immunity theft. The isolation and genomic analysis of bacteriophages by freshman college students provides an example of an authentic research experience for novice scientists.

The timing of puberty has important public health, clinical, and social implications. The plasticity of sexual development onset could be a mechanism that adapts to prevailing environmental conditions. Early-life nutrition may provide cues for the environment's suitability for reproduction. This review focuses on recent developments in our understanding of the role of diet in the timing of sexual maturation. Population-based observational studies consistently indicate that childhood obesity is related to the earlier onset of puberty in girls. Similarly, intake of animal foods has been associated with earlier sexual development, whereas vegetable protein intake is related to delayed maturation. Evidence for prenatal nutrition, infant feeding practices, and childhood intake of fat, carbohydrate, and micronutrients is inconsistent. Secondary analyses of prenatal and early-life randomized nutritional interventions with extended follow-up through peripubertal years would help clarify the role of nutrition in the timing of sexual maturation.

Higher red meat intake frequency during childhood is associated with an earlier age at menarche, whereas greater fatty fish intake frequency is associated with a later menarcheal age.

Pain is common among older adults and negatively impacts functioning. Sleep disturbances and mood disorders, specifically depression and anxiety, are closely associated with pain in older individuals, but the directionality of these associations remains unclear. In this study, we deconstruct long-term temporal effects of two key insomnia symptoms on incident pain into direct and indirect pathways, with focus on depression and anxiety symptoms, within a nationally representative sample. We utilized 2011-2013 data from the National Health and Aging Trends Study, a longitudinal survey of 2239 community-dwelling Medicare beneficiaries. Participants completed annual in-person interviews with assessments of sleep initiation and maintenance; depression, and anxiety (using the Patient Health Questionnaire-2 [PHQ-2] and the Generalized Anxiety Disorder Scale-2 [GAD-2] respectively); and bothersome pain. Causal mediation analysis was applied to examine direct effects of the two insomnia symptoms at baseline on incident pain, and their indirect effects through depression and anxiety symptoms. Almost one-third of the study participants were 69 years old or younger. A similar proportion reported bothersome pain in 2013. The two baseline insomnia symptoms predicted the development of pain. Adjusted analyses suggested that compared to older adults without the two baseline insomnia symptoms, participants with sleep initiation or maintenance difficulties had 24% (95% confidence interval [CI] 2%,51%) and 28% (95% CI 4%,55%) higher odds of incident pain, respectively. Anxiety symptoms partially mediated the relationship between the insomnia symptoms and incident pain, accounting for up to 17% of the total effect, but depressive symptoms did not. These results suggest that improved sleep or anxiety could reduce the risk for future pain.

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