The objective of this study was to investigate possible immune cytokine trends throughout a week-long surgical simulation mass-casualty training session in order to determine the effects of stress ino Show more
The objective of this study was to investigate possible immune cytokine trends throughout a week-long surgical simulation mass-casualty training session in order to determine the effects of stress inoculation on the immune system. Thirty-seven military medical students participated in a hyper-realistic surgical simulation training event conducted at Strategic Operations site in San Diego, California. Salivary samples were collected every morning of the stress training exercise for 4 consecutive days. Cortisol, along with a panel of 42 immune cytokines, was measured using multiplex enzyme-linked immunosorbent assays from Eve Technologies. The determined concentrations were averaged and plotted on a scatter plot, and then points were fit to a second-order polynomial trendline of best fit to measure. The cytokines epidermal growth factor, growth-related oncogene-α, interleukin (IL)-1α, and platelet-derived growth factor-AA followed a noted pattern of cortisol decrease throughout the week. In addition, cytokines IL-27, granulocyte colony stimulating factor, IL-10, and IL-13 demonstrated a late peak, followed by a return to baseline at the conclusion of training. Finally, the cytokine monocyte chemoattractant protein-1 displayed a decline throughout the week followed by an increase on the last day of stress training. Altogether, these results help to identify important biomarkers that may help to improve long-term stress adaptation and prevent post-traumatic stress disorder following exposure to repeated stress. Show less
Genetic loci for body mass index (BMI) in adolescence and young adulthood, a period of high risk for weight gain, are understudied, yet may yield important insight into the etiology of obesity and ear Show more
Genetic loci for body mass index (BMI) in adolescence and young adulthood, a period of high risk for weight gain, are understudied, yet may yield important insight into the etiology of obesity and early intervention. To identify novel genetic loci and examine the influence of known loci on BMI during this critical time period in late adolescence and early adulthood, we performed a two-stage meta-analysis using 14 genome-wide association studies in populations of European ancestry with data on BMI between ages 16 and 25 in up to 29 880 individuals. We identified seven independent loci (P < 5.0 × 10⁻⁸) near FTO (P = 3.72 × 10⁻²³), TMEM18 (P = 3.24 × 10⁻¹⁷), MC4R (P = 4.41 × 10⁻¹⁷), TNNI3K (P = 4.32 × 10⁻¹¹), SEC16B (P = 6.24 × 10⁻⁹), GNPDA2 (P = 1.11 × 10⁻⁸) and POMC (P = 4.94 × 10⁻⁸) as well as a potential secondary signal at the POMC locus (rs2118404, P = 2.4 × 10⁻⁵ after conditioning on the established single-nucleotide polymorphism at this locus) in adolescents and young adults. To evaluate the impact of the established genetic loci on BMI at these young ages, we examined differences between the effect sizes of 32 published BMI loci in European adult populations (aged 18-90) and those observed in our adolescent and young adult meta-analysis. Four loci (near PRKD1, TNNI3K, SEC16B and CADM2) had larger effects and one locus (near SH2B1) had a smaller effect on BMI during adolescence and young adulthood compared with older adults (P < 0.05). These results suggest that genetic loci for BMI can vary in their effects across the life course, underlying the importance of evaluating BMI at different ages. Show less