The SARS-CoV-2 viral load in COVID-19 patients is lower on face mask filters than on nasopharyngeal swabs.

Face masks and personal respirators are used to curb the transmission of SARS-CoV-2 in respiratory droplets; filters embedded in some personal protective equipment could be used as a non-invasive sample source for applications, including at-home testing, but information is needed about whether filters are suited to capture viral particles for SARS-CoV-2 detection. In this study, we generated inactivated virus-laden aerosols of 0.3-2 microns in diameter (0.9 µm mean diameter by mass) and dispersed the aerosolized viral particles onto electrostatic face mask filters. The limit of detection for inactivated coronaviruses SARS-CoV-2 and HCoV-NL63 extracted from filters was between 10 to 100 copies/filter for both viruses. Testing for SARS-CoV-2, using face mask filters and nasopharyngeal swabs collected from hospitalized COVID-19-patients, showed that filter samples offered reduced sensitivity (8.5% compared to nasopharyngeal swabs). The low concordance of SARS-CoV-2 detection between filters and nasopharyngeal swabs indicated that number of viral particles collected on the face mask filter was below the limit of detection for all patients but those with the highest viral loads. This indicated face masks are unsuitable to replace diagnostic nasopharyngeal swabs in COVID-19 diagnosis. The ability to detect nucleic acids on face mask filters may, however, find other uses worth future investigation

2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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ICAR: endoscopic skull‐base surgery

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Predicting performance on the United States Medical Licensing Examination Step 1 and Step 2 Clinical Knowledge using results from previous examinations

Humberto M Guiot,1,2 Hilton Franqui-Rivera1,3 1Division of Infectious Diseases, Department of Medicine, University of Puerto Rico School of Medicine, San Juan, PR, USA; 2Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan, PR, USA; 3Division of Cardiology, Department of Medicine, University of Puerto Rico School of Medicine, San Juan, PR, USA Background: Finding early specific indicators of failure in the United States Medical Licensing Examination (USMLE) Step 1 and Step 2 Clinical Knowledge (CK) could be used to develop early interventions that could solve deficiencies and help at-risk students to ultimately attain a passing score. This study was aimed at determining if the National Board of Medical Examiners (NBME) Comprehensive Basic Science Examination (CBSE) could predict a passing score during the USMLE Step 1. We also assessed if the NBME Medicine Clinical Science Subject Examination (CSSE) or the USMLE Step 1 could predict passing scores during the USMLE Step 2 CK.Methods: Gender and scores from 724 students who took the USMLE Step 1 were linked and analyzed with the scores of the NBME CBSE, the NBME Medicine CSSE, and the USMLE Step 2 CK using IBM-SPSS.Results: There were significant correlations between the scores from NBME CBSE and USMLE Step 1 (r=0.73, P≤0.001), between the scores from the NBME Medicine CSSE and the USMLE Step 2 CK (r=0.572, P≤0.001), and between the scores from the USMLE Step 1 and Step 2 CK (r=0.698, P≤0.001). Students with scores <66 in the NBME CBSE were less likely to approve the USMLE Step 1 on their first attempt (P≤0.00001). There was a significant correlation (r=0.684, P≤0.0001) between a score of ≥208 in the USMLE Step 1 and passing the Step 2 CK on the first attempt.Conclusion: A score <66 in the NBME CBSE might indicate failure during the USMLE Step 1 first take. Similarly, a score <208 in the USMLE Step 1 might predict failure in the USMLE Step 2 CK. Keywords: USMLE Step 1, USMLE Step 2 CK, NBME CBSE, NBME Medicine CSS

Abordagem neuroendoscopica transnasal transeptal para a região selar: estudo de 30 casos Neuroendoscopic endonasal transseptal approach to the sellar region: study of 30 cases

Uma abordagem neurocirúrgica endoscópica transeptal transesfenoidal foi realizada em 30 casos de patologias diversas da região selar. O uso do endoscópio permite boa inspeção e diferenciação entre tumor e tecido normal, resultando em microdissecção do tumor, com preservação funcional da hipófise. A visão angular do endoscópio, auxilia na retirada das projeções tumorais para e supra selar. O uso da via transeptal transesfenoidal endoscópica, evita as complicações da via sublabial, como luxação dentária, perfuração de septo nasal, sinequias e formação de crostas. Os inconvenientes do uso do endoscópio são a diminuição da profundidade de campo, necessidade de constante controle do mesmo, e exige experiência com as técnicas endoscópicas.<br>An endoscopic endonasal transsphenoidal approach to the sella was performed in 30 patients. The use of endoscope allowed close inspection and differentiation between tumor tissue and glandular remains, resulting in micro dissection of the tumor with maximumu preservation of pituitary function. The angled view of the endoscope helps gross total removal of the tumor tissue, from the supra and para sellar extension. The endonasal transseptal endoscopic approach helps from dental problems, and lowers incidence of septal perforation, synechia, and crust formation. However the endoscopic approach has drawbacks. Its decreases the depth of field, needs constant manual control of the endoscope, and requires experience with the endoscope technique