Cardiovascular Adaptations of Space Travel: A Systematic Review.

INTRODUCTION: Space travel imposes significant gravitational and radiation stress on both cellular and systemic physiology, resulting in myriad cardiovascular changes that have not been fully characterized. METHODS: We conducted a systematic review of the cellular and clinical adaptations of the cardiovascular system after exposure to real or simulated space travel in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed and Cochrane databases were searched in June 2021 for all peer-reviewed articles published since 1950 related to the following search terms entered in separate pairs: "cardiology and space" and "cardiology and astronaut." Only cellular and clinical studies in English concerning the investigation of cardiology and space were included. RESULTS: Eighteen studies were identified, comprising 14 clinical and 4 cellular investigations. On the genetic level, pluripotent stem cells in humans and cardiomyocytes in mice displayed increased beat irregularity, with clinical studies revealing a persistent increase in heart rate after space travel. Further cardiovascular adaptations included a higher frequency of orthostatic tachycardia but no evidence of orthostatic hypotension, after return to sea level. Hemoglobin concentration was also consistently decreased after return to Earth. No consistent change in systolic or diastolic blood pressure or any clinically significant arrhythmias were observed during or after space travel. CONCLUSION: Changes in oxygen carrying capacity, blood pressure, and post-flight orthostatic tachycardia may serve as reasons to further screen for pre-existing anemic and hypotensive conditions among astronauts.

Implementing a Skin Cancer Prevention Lesson to Enact Institutional Change: A Schoolwide Survey.

BACKGROUND: Schools can play a major role in protecting students from skin cancer by instituting preventive policies and educational programs. METHODS: A high school-wide study was conducted to assess students' current understanding of skin cancer prevention, provide an up-to-date instruction lesson, and evaluate changes in students' knowledge and behaviors. RESULTS: Written surveys were distributed to 2,688 high school students with a return rate of 38.1% (n = 1,025). Surveys were administered prior to (survey 1), immediately after (survey 2), and 1 month after (survey 3) presenting a video lesson. Significant changes in knowledge gain (an increase from survey 1 to survey 2), knowledge decay (a decrease from survey 2 to survey 3), and knowledge persistence (an increase from survey 1 to survey 3) throughout all grade levels were found. Behavioral changes included an increase in students wearing sunscreen 5-7 days per week (p < 0.001) and students examining themselves for changing moles (p = 0.10). With this survey, the Health Education Framework for California Public Schools was revised to include updated recommendations regarding skin cancer prevention efforts in schools. CONCLUSIONS: A skin cancer video lesson given to high school students effectively increased students' knowledge and promoted healthy behaviors.