ABSTRACT
Background: The coronavirus disease (COVID-19) pandemic has been a source of disruption, changing the face of medical education. In response to infection control measures at the University of California, San Diego, the hybrid in-person and recorded preclerkship curriculum was converted to a completely virtual format. The impact of this exclusive virtual teaching platform on the quality of trainee education is unknown. Objective: To determine the efficacy of a virtual course, relative to traditional hybrid in-person and recorded teaching, and to assess the impact of supplementary educational material on knowledge acquisition. Methods: A retrospective observational cohort study was performed to assess an introductory course, held mostly in person in 2019 versus completely virtual in 2020, for first-year medical students and second-year pharmacy students at the University of California, San Diego, School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences. Results: The midterm and final examination scores were similar for the hybrid and virtual courses. There was no association between the hours of recorded lectures watched and final examination scores for either course. In the 2019 in-person and recorded course, students who demonstrated consistent on-time use of practice quizzes scored statistically higher on the final examination (P = 0.0066). In the 2020 virtual course, students who downloaded quizzes regularly had statistically higher scores on the midterm examination (P < 0.0001). Conclusion: The similar examination scores for the hybrid in-person and recorded and exclusively virtual courses suggest that the short-term knowledge acquired was equivalent, independent of the modality with which the content was delivered. Consistent on-time use of practice quizzes was associated with higher examination scores. Future studies are needed to assess the difference between a completely in-person versus virtual curriculum.
ABSTRACT
Conventional smoking is known to both increase susceptibility to infection and drive inflammation within the lungs. Recently, smokers have been found to be at higher risk of developing severe forms of coronavirus disease 2019 (COVID-19). E-cigarette aerosol inhalation (vaping) has been associated with several inflammatory lung disorders, including the recent e-cigarette or vaping product use-associated lung injury (EVALI) epidemic, and recent studies have suggested that vaping alters host susceptibility to pathogens such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To assess the impact of vaping on lung inflammatory pathways, including the angiotensin-converting enzyme 2 (ACE2) receptor known to be involved in SARS-CoV-2 infection, mice were exposed to e-cigarette aerosols for 60 min daily for 1-6 months and underwent gene expression analysis. Hierarchical clustering revealed extensive gene expression changes occurred in the lungs of both inbred C57BL/6 mice and outbred CD1 mice, with 2,933 gene expression changes in C57BL/6 mice, and 2,818 gene expression changes in CD1 mice (>abs 1.25-fold change). Particularly, large reductions in IgA and CD4 were identified, indicating impairment of host responses to pathogens via reductions in immunoglobulins and CD4 T cells. CD177, facmr, tlr9, fcgr1, and ccr2 were also reduced, consistent with diminished host defenses via decreased neutrophils and/or monocytes in the lungs. Gene set enrichment (GSE) plots demonstrated upregulation of gene expression related to cell activation specifically in neutrophils. As neutrophils are a potential driver of acute lung injury in COVID-19, increased neutrophil activation in the lungs suggests that vapers are at higher risk of developing more severe forms of COVID-19. The receptor through which SARS-CoV-2 infects host cells, ACE2, was found to have moderate upregulation in mice exposed to unflavored vape pens, and further upregulation (six-fold) with JUUL mint aerosol exposure. No changes were found in mice exposed to unflavored Mod device-generated aerosols. These findings suggest that specific vaping devices and components of e-liquids have an effect on ACE2 expression, thus potentially increasing susceptibility to SARS-CoV-2. In addition, exposure to e-cigarette aerosols both with and without nicotine led to alterations in eicosanoid lipid profiles within the BAL. These data demonstrate that chronic, daily inhalation of e-cigarette aerosols fundamentally alters the inflammatory and immune state of the lungs. Thus, e-cigarette vapers may be at higher risk of developing infections and inflammatory disorders of the lungs.