Prehospital Testing and Surveillance for SARS-CoV-2: A Special Report from the Sacramento (California USA) Mobile Integrated Health Unit.

INTRODUCTION: Coronavirus disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has killed nearly 800,000 Americans since early 2020. The disease has disproportionately affected older Americans, men, persons of color, and those living in congregate living facilities. Sacramento County (California USA) has used a novel Mobile Integrated Health Unit (MIH) to test hundreds of patients who dwell in congregate living facilities, including skilled nursing facilities (SNF), residential care facilities (ie, assisted living facilities [ALF] and board and care facilities [BCF]), and inpatient psychiatric facilities (PSY), for SARS-CoV-2. METHODS: The MIH was authorized and rapidly created at the beginning of the COVID-19 pandemic as a joint venture between the Sacramento County Department of Public Health (SCDPH) and several fire-based Emergency Medical Services (EMS) agencies within the county to perform SARS-CoV-2 testing and surveillance in a prehospital setting at a number of congregate living facilities. All adult patients (≥18 years) who were tested for SARS-CoV-2 infection by the MIH from March 31, 2020 through April 30, 2020 and lived in congregate living facilities were included in this retrospective descriptive cohort. Demographic and laboratory data were collected to describe the cohort of patients tested by the MIH. RESULTS: During the study period, the MIH tested a total of 323 patients from 15 facilities in Sacramento County. The median age of patients tested was 66 years and the majority were female (72%). Overall, 72 patients (22%) tested positive for SARS-CoV-2 in congregate living settings, a higher rate of positivity than was measured across the county during the same time period. CONCLUSION: The MIH was a novel method of epidemic surveillance that succeeded in delivering effective and efficient testing to patients who reside in congregate living facilities and was able to accurately identify pockets of infection within otherwise low prevalence areas. Cooperative prehospital models are an effective model to deliver out-of-hospital testing and disease surveillance that may serve as a blueprint for community-based care delivery for a number of disease states and future epidemics or pandemics.

Chronic intermittent electronic cigarette exposure induces cardiac dysfunction and atherosclerosis in apolipoprotein-E knockout mice.

Electronic cigarettes (e-cigarettes), also known as electronic nicotine delivery systems, are a popular alternative to conventional nicotine cigarettes, both among smokers and those who have never smoked. In spite of the widespread use of e-cigarettes and the proposed detrimental cardiac and atherosclerotic effects of nicotine, the effects of e-cigarettes on these systems are not known. In this study, we investigated the cardiovascular and cardiac effects of e-cigarettes with and without nicotine in apolipoprotein-E knockout (ApoE-/-) mice. We developed an e-cigarette exposure model that delivers nicotine in a manner similar to that of human e-cigarettes users. Using commercially available e-cigarettes, bluCig PLUS, ApoE-/- mice were exposed to saline, e-cigarette without nicotine [e-cigarette (0%)], and e-cigarette with 2.4% nicotine [e-cigarette (2.4%)] aerosol for 12 wk. Echocardiographic data show that mice treated with e-cigarette (2.4%) had decreased left ventricular fractional shortening and ejection fraction compared with e-cigarette (0%) and saline. Ventricular transcriptomic analysis revealed changes in genes associated with metabolism, circadian rhythm, and inflammation in e-cigarette (2.4%)-treated ApoE-/- mice. Transmission electron microscopy revealed that cardiomyocytes of mice treated with e-cigarette (2.4%) exhibited ultrastructural abnormalities indicative of cardiomyopathy. Additionally, we observed increased oxidative stress and mitochondrial DNA mutations in mice treated with e-cigarette (2.4%). ApoE-/- mice on e-cigarette (2.4%) had also increased atherosclerotic lesions compared with saline aerosol-treated mice. These results demonstrate adverse effects of e-cigarettes on cardiac function in mice.NEW & NOTEWORTHY The present study is the first to show that mice exposed to nicotine electronic cigarettes (e-cigarettes) have decreased cardiac fractional shortening and ejection fraction in comparison with controls. RNA-seq analysis reveals a proinflammatory phenotype induced by e-cigarettes with nicotine. We also found increased atherosclerosis in the aortic root of mice treated with e-cigarettes with nicotine. Our results show that e-cigarettes with nicotine lead to detrimental effects on the heart that should serve as a warning to e-cigarette users and agencies that regulate them.

Vitamin D induces myogenic differentiation in skeletal muscle derived stem cells.

Skeletal muscle wasting is a serious disorder associated with health conditions such as aging, chronic kidney disease and AIDS. Vitamin D is most widely recognized for its regulation of calcium and phosphate homeostasis in relation to bone development and maintenance. Recently, vitamin D supplementation has been shown to improve muscle performance and reduce the risk of falls in vitamin D deficient older adults. However, little is known of the underlying molecular mechanism(s) or the role it plays in myogenic differentiation. We examined the effect of 1,25-D3 on myogenic cell differentiation in skeletal muscle derived stem cells. Primary cultures of skeletal muscle satellite cells were isolated from the tibialis anterior, soleus and gastrocnemius muscles of 8-week-old C57/BL6 male mice and then treated with 1,25-D3 The efficiency of satellite cells isolation determined by PAX7+ cells was 81%, and they expressed VDR. Incubation of satellite cells with 1,25-D3 induces increased expression of: (i) MYOD, (ii) MYOG, (iii) MYC2, (iv) skeletal muscle fast troponin I and T, (v) MYH1, (vi) IGF1 and 2, (vii) FGF1 and 2, (viii) BMP4, (ix) MMP9 and (x) FST. It also promotes myotube formation and decreases the expression of MSTN. In conclusion, 1,25-D3 promoted a robust myogenic effect on satellite cells responsible for the regeneration of muscle after injury or muscle waste. This study provides a mechanistic justification for vitamin D supplementation in conditions characterized by loss of muscle mass and also in vitamin D deficient older adults with reduced muscle mass and strength, and increased risk of falls.