Frontiers in microbiology
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Frontiers in microbiology · Jan 2020
ReviewMain Clinical Features of COVID-19 and Potential Prognostic and Therapeutic Value of the Microbiota in SARS-CoV-2 Infections.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2), has become a pandemic, infecting more than 4,000,000 people worldwide. This review describes the main clinical features of COVID-19 and potential role of microbiota in COVID-19. SARS-CoV and SARS-CoV-2 have 79.5% nucleotide sequence identity and use angiotensin-converting enzyme 2 (ACE2) receptors to enter host cells. ⋯ Moreover, the gut microbiota enhances antiviral immunity by increasing the number and function of immune cells, decreasing immunopathology, and stimulating interferon production. In turn, respiratory viruses are known to influence microbial composition in the lung and intestine. Therefore, the analysis of changes in the microbiota during SARS-CoV-2 infection may help predict patient outcomes and allow the development of microbiota-based therapies.
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Frontiers in microbiology · Jan 2020
The Strengths of Scanning Electron Microscopy in Deciphering SARS-CoV-2 Infectious Cycle.
Electron microscopy is a powerful tool in the field of microbiology. It has played a key role in the rapid diagnosis of viruses in patient samples and has contributed significantly to the clarification of virus structure and function, helping to guide the public health response to emerging viral infections. In the present study, we used scanning electron microscopy (SEM) to study the infectious cycle of SARS-CoV-2 in Vero E6 cells and we controlled some key findings by classical transmission electronic microscopy (TEM). ⋯ New SARS-CoV-2 particles were expelled from the cells, through cell lysis or by fusion of virus containing vacuoles with the cell plasma membrane. Overall, this cycle is highly comparable to that of SARS-CoV. By providing a detailed and complete SARS-CoV-2 infectious cycle, SEM proves to be a very rapid and efficient tool compared to classical TEM.
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Frontiers in microbiology · Jan 2020
Fusobacterium nucleatum Promotes the Progression of Colorectal Cancer Through Cdk5-Activated Wnt/β-Catenin Signaling.
Growing evidence supports the direct link of Fusobacterium nucleatum with colorectal cancer (CRC). However, to date, the underlying mechanism of action remains poorly understood. In this study, we examined the effects of F. nucleatum on the progression of CRC and investigated whether cyclin-dependent kinase 5 (Cdk5) is involved in the effect through activating the Wnt/β-catenin signaling pathway. ⋯ The results of this study demonstrate that F. nucleatum orchestrates a molecular network involving the direct role of Cdk5 in activating Wnt/β-catenin signaling to modulate CRC progression. Thus, in-depth investigations of F. nucleatum-associated molecular pathways may offer valuable insight into the pathogenesis of CRC, which may help further the development of treatment for this disease.
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The 2019 novel coronavirus disease (COVID-19), which is caused by the novel beta coronavirus, SARS-CoV-2, is currently prevalent all over the world, causing thousands of deaths with relatively high virulence. Like two other notable beta coronaviruses, severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus (MERS-CoV), SARS-CoV-2 can lead to severe contagious respiratory disease. Due to impaired cellular immunity and physiological changes, pregnant women are susceptible to respiratory disease and are more likely to develop severe pneumonia. ⋯ However, limited data are available for the clinical course and management of COVID-19 in pregnancy. Therefore, we conducted this review to identify strategies for the obstetric management of COVID-19. We compared the clinical course and outcomes of COVID-19, SARS, and MERS in pregnancy and discussed several drugs for the treatment of COVID-19 in pregnancy.
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Frontiers in microbiology · Jan 2020
ReviewThe Interplay Between Respiratory Microbiota and Innate Immunity in Flavor E-Cigarette Vaping Induced Lung Dysfunction.
Global usage of electronic nicotine delivery systems (ENDS) has been increasing in the last decade. ENDS are non-combustible tobacco products that heat and aerosolize a liquid containing humectants, with added flavorings and often nicotine. Though ENDS are promoted as a less harmful alternative to smoking, current evidence links their use to a wide range of deleterious health effects including acute and chronic lung damage. ⋯ Alterations of the normal respiratory microbiota have been associated with chronic obstructive pulmonary disease (COPD), asthma, atopy and cystic fibrosis complications which are strongly associated with smoking and potentially with ENDS use. Little is known about the short-and long-term effects of ENDS on the respiratory microbiota, their impact on the innate immune response and their link to pulmonary health and disease. Here we review the interaction between the innate immune system and the respiratory microbiota in the pathogenesis of ENDS-induced pulmonary dysfunction and identify future areas of research.