Alternative workflow for COVID-19 diagnosis using direct RT-PCR screening

Objective: COVID-19 is presently the most serious public health concern and diagnosis is a principal tool for controlling and monitoring the spread of the disease. This study aimed to evaluate the efficiency of direct RT-PCR (dRT-PCR) for detection of SARS-CoV-2. Methods: Twenty-seven nasopharyngeal swabs from symptomatic individuals were evaluated. Standard RT-PCR was conducted, and for dRT-PCR the samples were preheated before amplification. Results: Positive agreement was 63.2% and negative agreement was 100%, being moderately in accord. Conclusion: dRT-PCR may be an alternative for screening symptomatic patients and a reliable option during an eventual shortage of viral RNA purification kits.

Objetivo: A COVID-19 é atualmente um sério problema de saúde pública e o diagnóstico é a principal ferramenta para controlar e monitorar a propagação da doença. Este estudo teve como objetivo avaliar a eficiência da RT-PCR direta (dRT-PCR) para detecção do SARS-CoV-2. Métodos: Vinte e sete amostras de swab nasofaríngeo de indivíduos sintomáticos foram avaliados. A RT-PCR padrão foi realizada e para a dRT-PCR as amostras foram pré-aquecidas antes da amplificação. Resultados: A concordância positiva foi de 63,2% e a concordância negativa foi de 100%, sendo moderadamente concordante. Conclusão: A dRT-PCR pode ser uma alternativa para a triagem de pacientes sintomáticos e uma opção confiável durante uma eventual escassez de kits de purificação de RNA viral.

Evaluation of alternative RNA extraction methods for detection of SARS-CoV-2 in nasopharyngeal samples using the recommended CDC primer-probe set.

Background: The efficiency of isolation and purification of the viral genome is a critical step to the accuracy and reliability of RT-qPCR to detect SARS-CoV-2. However, COVID-19 testing laboratories were overwhelmed by a surge in diagnostic demand that affected supply chains especially in low and middle-income facilities. Objectives: Thus, this study compares the performance of alternative methods to extraction and purification of viral RNA in samples of patients diagnosed with COVID-19. Study design: Nasopharyngeal swabs were submitted to three in-house protocols and three commercial methods; viral genome was detected using the primer-probe (N1 and N2) described by CDC and viral load of samples were determined. Results: The in-house protocols resulted in detection of virus in 82.4 to 86.3% of samples and commercial methods in 94.1 to 98%. The disagreement results were observed in samples with low viral load or below the estimated limit of detection of RT-qPCR. Conclusion: The simplified methods proposed might be less reliable for patients with low viral load and alternative commercial methods showed comparable performance.

Hematological and immunological effects of stress of air traffic controllers in northeastern Brazil

BACKGROUND: Several studies have shown that stress and emotional reactions can affect immune responses in animals and humans. OBJECTIVE: The aim of this study was to evaluate hematological and immunological effects of stress on air traffic controllers. METHODS: Thirty air traffic controllers and 15 aeronautical information service operators were evaluated. The groups were divided as information service operators with 10 years or more of experience (AIS>10) and with less than 10 years in the profession (AIS<10) and air traffic controllers with 10 years or more of experience (ATCo>10) and with less than 10 years in the profession (ATCo<10). Blood samples were drawn at 8:00 a.m. and 2:00 p.m. The paired t-test was used to compare monocyte and nitric oxide concentrations and ANOVA was used for the other parameters. RESULTS: The ATCo>10 group presented a significantly lower phagocytosis rate of monocytes at 2:00 p.m. compared to 8:00 a.m. Moreover, the ATCo>10 group presented lower hemoglobin, mean corpuscular hemoglobin concentration, platelet and leukocyte levels, and increased cortisol concentrations at 8:00 a.m. compared to the other groups. Additionally, this group had lower phagocytosis rate of monocytes, and hemoglobin, platelet, leukocyte, basophils and nitric oxide levels at 2:00 p.m. compared to the other groups. CONCLUSION: Stress seems to greatly affect immune responses of air traffic controllers with more than ten years of experience.

Hematological and immunological effects of stress of air traffic controllers in northeastern Brazil.

BACKGROUND: Several studies have shown that stress and emotional reactions can affect immune responses in animals and humans. OBJECTIVE: The aim of this study was to evaluate hematological and immunological effects of stress on air traffic controllers. METHODS: Thirty air traffic controllers and 15 aeronautical information service operators were evaluated. The groups were divided as information service operators with 10 years or more of experience (AIS≥10) and with less than 10 years in the profession (AIS<10) and air traffic controllers with 10 years or more of experience (ATCo≥10) and with less than 10 years in the profession (ATCo<10). Blood samples were drawn at 8:00 a.m. and 2:00 p.m. The paired t-test was used to compare monocyte and nitric oxide concentrations and ANOVA was used for the other parameters. RESULTS: The ATCo≥10 group presented a significantly lower phagocytosis rate of monocytes at 2:00 p.m. compared to 8:00 a.m. Moreover, the ATCo≥10 group presented lower hemoglobin, mean corpuscular hemoglobin concentration, platelet and leukocyte levels, and increased cortisol concentrations at 8:00 a.m. compared to the other groups. Additionally, this group had lower phagocytosis rate of monocytes, and hemoglobin, platelet, leukocyte, basophils and nitric oxide levels at 2:00 p.m. compared to the other groups. CONCLUSION: Stress seems to greatly affect immune responses of air traffic controllers with more than ten years of experience.

Tratramento neonatal com inibidor seletivo da recaptação de noradrenalina altera o consumo alimentar e a ingestão hídrica na vida adulta em ratos / Neonatal treatment with selective noradrenaline reuptake inhibitor alter the food and water intake in adult life in rats

RESUMO: Durante o período crítico de desenvolvimento do sistema nervoso, o organismo é vulnerável a agressões de diversas naturezas, que podem acarretar transtornos morfofuncionais na vida adulta. A construção do comportamento alimentar é vulnerável a estas agressões, sendo importante para a sobrevivência da espécie e, portanto, alvo de estudos. O objetivo deste trabalho foi estudar o efeito da manipulação farmacológica do sistema noradrenérgico, através da inibição da recaptação de noradrenalina, durante o período neonatal e as repercussões dessa agressão sobre o consumo alimentar, na vida adulta. Os animais foram tratados diariamente, durante os 21ºdias de vida com reboxetina (20mg/Kg de peso), um inibidor seletivo da recaptação de noradrenalina (NARI) ou solução salina (NaCI 0,9por cento). Aos 60 dias foi avaliado o consumo alimentar e a ingestão hídrica. Os animais tratados com salina. Concluímos que a agressão farmacológica do sistema noradrenérgico durante o perídoso neonatal, pode alterar de forma duradoura o consumo alimentar e a ingestão hídrica. Essas alterações sugerem que o tratamento pode alterar morfofucionalmente estruturas relacionadas a regulação do comportamento alimentar e da ingestão hídrica, levando a alterações comportamentais na vida adulta