Effects of Sport Related Concussion on Academic Performance in High School Athletes

Background. Concussive impacts to the head are a natural part of most athletic competition. Even in sports that do not permit player contact, incidental contact that can result in concussion often occurs. This dissertation addresses the general hypothesis that sport related concussions have a negative impact on academic performance in high school athletes. Study Design. A systematic review of current literature on the post-acute neurocognitive effects of concussion provides an introduction to the importance of this study. A retrospective cohort of athletes participating in school sports in a public school district is assessed for changes in school attendance and academic performance following concussion compared to ankle or leg injury. Methods. The systematic review included meta-analytic methods. Analysis of the retrospective cohort included longitudinal graphical and multivariable random coefficient methods that characterized changes in academic performance over time in high school athletes with and without concussion. Random coefficient models were used to assess effect modification by predictor variables including gender and age. Results. Researchers have shown that adolescent athletes experience a range of neurocognitive symptoms six or more days following concussion injury. In the retrospective cohort analyses, athletes with concussion injuries have greater odd of being grade 9 (OR=2.2, p<0.001, 95%CI 1.5-3.2) or grade 10 (OR 2.1, p<0.001, 95%CI 1.5-3.1) than grade 12 and had greater odds of an increase in the number of days absent from school (OR=1.7, p<0.011, 95%CI 1.3-2.2) when compared to athletes with ankle or leg injury. Analyses of a subgroup of younger athletes (grades 9 and 10) with more severe injuries indicate a 16% greater decline in academic performance for the group with concussion injury than those with ankle or leg injury (coeff= -0.18, p=0.017, 95% CI= -0.32 to -0.03). Conclusions. These analyses suggest that young athletes with concussion injury are at risk for decline in academic performance. Increased absence from school results in decreased instruction time, social isolation, and other factors that may negatively impact academic achievement. Future research is warranted, examining academic performance in high school athletes with concussion injury.Ph.D., Public Health -- Drexel University, 201

Investigation of COVID-19 Outbreak among Wildland Firefighters during Wildfire Response, Colorado, USA, 2020

A COVID-19 outbreak occurred among Cameron Peak Fire responders in Colorado, USA, during August 2020–January 2021. The Cameron Peak Fire was the largest recorded wildfire in Colorado history, lasting August–December 2020. At least 6,123 responders were involved, including 1,260 firefighters in 63 crews who mobilized to the fire camps. A total of 79 COVID-19 cases were identified among responders, and 273 close contacts were quarantined. State and local public health investigated the outbreak and coordinated with wildfire management teams to prevent disease spread. We performed whole-genome sequencing and applied social network analysis to visualize clusters and transmission dynamics. Phylogenetic analysis identified 8 lineages among sequenced specimens, implying multiple introductions. Social network analysis identified spread between and within crews. Strategies such as implementing symptom screening and testing of arriving responders, educating responders about overlapping symptoms of smoke inhalation and COVID-19, improving physical distancing of crews, and encouraging vaccinations are recommended

Ku Is Important for Telomere Maintenance, but Not for Differential Expression of Telomeric VSG Genes, in African Trypanosomes.

Trypanosome antigenic variation, involving differential expression of variant surface glycoprotein (VSG) genes, has a strong association with telomeres and with DNA recombination. All expressed VSGs are telomeric, and differential activation involves recombination into the telomeric environment or silencing/activation of subtelomeric promoters. A number of pathogen contingency gene systems associated with immune evasion involve telomeric loci, which has prompted speculation that chromosome ends provide conditions conducive for the operation of rapid gene switching mechanisms. Ku is a protein associated with eukaryotic telomeres that is directly involved in DNA recombination and in gene silencing. We have tested the hypothesis that Ku in trypanosomes is centrally involved in differential VSG expression. We show, via the generation of null mutants, that trypanosome Ku is closely involved in telomere length maintenance, more so for a transcriptionally active than an inactive telomere, but exhibits no detectable influence on DNA double strand break repair. The absence of Ku and the consequent great shortening of telomeres had no detectable influence either on the rate of VSG switching or on the silencing of the telomeric promoters of the VSG subset that is expressed in the tsetse fly