ABSTRACT
The novel coronavirus (2019-nCoV) has recently caused a large-scale outbreak of viral pneumonia both in China and worldwide. In this study, we obtained the entire genome sequence of 777 new coronavirus strains as of 29 February 2020 from a public gene bank. Bioinformatics analysis of these strains indicated that the mutation rate of these new coronaviruses is not high at present, similar to the mutation rate of the severe acute respiratory syndrome (SARS) virus. The similarities of 2019-nCoV and SARS virus suggested that the S and ORF6 proteins shared a low similarity, while the E protein shared the higher similarity. The 2019-nCoV sequence has similar potential phosphorylation sites and glycosylation sites on the surface protein and the ORF1ab polyprotein as the SARS virus; however, there are differences in potential modification sites between the Chinese strain and some American strains. At the same time, we proposed two possible recombination sites for 2019-nCoV. Based on the results of the skyline, we speculate that the activity of the gene population of 2019-nCoV may be before the end of 2019. As the scope of the 2019-nCoV infection further expands, it may produce different adaptive evolutions due to different environments. Finally, evolutionary genetic analysis can be a useful resource for studying the spread and virulence of 2019-nCoV, which are essential aspects of preventive and precise medicine.
Subject(s)
COVID-19/classification , Phylogeny , Bayes Theorem , COVID-19/genetics , COVID-19/virology , Evolution, Molecular , Humans , Severe acute respiratory syndrome-related coronavirus/genetics , Severe acute respiratory syndrome-related coronavirus/isolation & purificationABSTRACT
The novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a major pandemic outbreak recently. Various diagnostic technologies have been under active development. The novel coronavirus disease (COVID-19) may induce pulmonary failures, and chest X-ray imaging becomes one of the major confirmed diagnostic technologies. The very limited number of publicly available samples has rendered the training of the deep neural networks unstable and inaccurate. This study proposed a two-step transfer learning pipeline and a deep residual network framework COVID19XrayNet for the COVID-19 detection problem based on chest X-ray images. COVID19XrayNet firstly tunes the transferred model on a large dataset of chest X-ray images, which is further tuned using a small dataset of annotated chest X-ray images. The final model achieved 0.9108 accuracy. The experimental data also suggested that the model may be improved with more training samples being released. COVID19XrayNet, a two-step transfer learning framework designed for biomedical images.
Subject(s)
Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Deep Learning , Lung/diagnostic imaging , Models, Biological , Neural Networks, Computer , Pneumonia, Viral/diagnosis , X-Rays , Algorithms , Betacoronavirus , COVID-19 , COVID-19 Testing , Coronavirus , Coronavirus Infections/complications , Coronavirus Infections/diagnostic imaging , Coronavirus Infections/virology , Databases, Factual , Datasets as Topic , Humans , Machine Learning , Pandemics , Pneumonia/diagnosis , Pneumonia/diagnostic imaging , Pneumonia/etiology , Pneumonia/virology , Pneumonia, Viral/complications , Pneumonia, Viral/diagnostic imaging , Pneumonia, Viral/virology , Radiography/methods , Reference Values , SARS-CoV-2 , Tomography, X-Ray Computed/methodsABSTRACT
The recent outbreak of the coronavirus disease-2019 (COVID-19) caused serious challenges to the human society in China and across the world. COVID-19 induced pneumonia in human hosts and carried a highly inter-person contagiousness. The COVID-19 patients may carry severe symptoms, and some of them may even die of major organ failures. This study utilized the machine learning algorithms to build the COVID-19 severeness detection model. Support vector machine (SVM) demonstrated a promising detection accuracy after 32 features were detected to be significantly associated with the COVID-19 severeness. These 32 features were further screened for inter-feature redundancies. The final SVM model was trained using 28 features and achieved the overall accuracy 0.8148. This work may facilitate the risk estimation of whether the COVID-19 patients would develop the severe symptoms. The 28 COVID-19 severeness associated biomarkers may also be investigated for their underlining mechanisms how they were involved in the COVID-19 infections.