ABSTRACT
We evaluated the effect of different respiratory protective masks (RPM) on ventilatory efficiency and operating lung volumes in a recreational runner. A healthy 36-years-old male runner underwent a pulmonary function test and cardiorespiratory exercise test with different RPM types and no mask (NM). Lung volumes and airflow resistance were similar regarding surgical and 3D knit masks compared to NM. Lower functional vital capacity and forced expiratory volume in 1 second were observed for N95 compared to NM. Regarding ventilatory efficiency analysis, lower values for VE/VCO2 slope in the interval at rest-respiratory compensation point and at rest-peak of exercise were observed for the surgical, 3D knit, and N95 masks compared to NM. Tidal flow volume loop analysis showed an increase in end-expiratory lung volume (EELV) in the interval 80% of the ventilatory anaerobic threshold-peak of exercise, while there was a decrease with NM. Lower VO2max was observed for surgical, 3D knit, and N95 masks compared to NM and lower speed at VO2max. The athlete reported greater comfort with 3D knit compared to surgical and N95 masks. The use of different RPM types during a progressive running exercise by a recreational runner showed lower ventilatory response and exercise tolerance, as well as increased EELV, perceived exertion, and respiratory discomfort. © 2021 Edizioni Minerva Medica. All rights reserved.
ABSTRACT
Phylogenetic analysis has demonstrated that the etiologic agent of the 2020 pandemic outbreak is a betacoronavirus named SARS-CoV-2. For public health interventions, a diagnostic test with high sensitivity and specificity is required. The gold standard protocol for diagnosis by the Word Health Organization (WHO) is RT-PCR. To detect low viral loads and perform large-scale screening, a low-cost diagnostic test is necessary. Here, we developed a cost-effective test capable of detecting SARS-CoV-2. We validated an auxiliary protocol for molecular diagnosis with the SYBR Green RT-PCR methodology to successfully screen negative cases of SARS-CoV-2. Our results revealed a set of primers with high specificity and no homology with other viruses from the Coronovideae family or human respiratory tract pathogenic viruses, presenting with complementarity only for rhinoviruses/enteroviruses and Legionella spp. Optimization of the annealing temperature and polymerization time led to a high specificity in the PCR products. We have developed a more affordable and swift methodology for negative SARS-CoV-2 screening. This methodology can be applied on a large scale to soften panic and economic burden through guidance for isolation strategies.
Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Organic Chemicals , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2 , Benzothiazoles , DNA, Single-Stranded , Diamines , Enterovirus , Genome, Viral , Humans , Phylogeny , Polymerase Chain Reaction , Quinolines , Rhinovirus , Sensitivity and Specificity , Temperature , Viral LoadABSTRACT
Background: Pregnant women are susceptible to the novel coronavirus (SARS-CoV-2) and the consequences on the fetus are still uncertain. Here, we present a case of a pregnant woman with subclinical hypothyroidism and PAI-1 4G/5G mutation who was infected with SARS-CoV-2 at the end of the third trimester of pregnancy. Methods: nested PCR were performed to detect the virus, followed by ssDNA sequencing. Results: transplacental transmission of SARS-CoV-2 can cause placental inflammation, ischemia and neonatal viremia, with complications such as preterm labor and damage to the placental barrier in patients with PAI-1 4G/5G mutation. Conclusion: we show the possibility of transplacental transmission of SARS-CoV-2 infection during the last weeks of pregnancy.