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Atmosphere ; 13(5):702, 2022.
Article in English | ProQuest Central | ID: covidwho-1875465


It is difficult to improve the seasonal prediction skill of winter temperature over North China, owing to the complex dynamics of East Asian winter and the relatively low prediction skill level of current climate models. Deep learning (DL) may be an informative and promising tool to enhance seasonal prediction, particularly in regions where the underlying mechanisms are not clear. Here, using a DL model based on the Convolutional Neural Network (CNN), we have found that the prediction skill for North China winter temperature (NCWT) can be extended up to five months by considering the remote impact of the Northeast Pacific sea-surface temperature (SST) on North China. Based on historical simulations of winter temperatures in North China, we selected six CMIP5 models with relatively small deviations for training the CNN, and the period chosen for training was 1852–1991. The N1 - ERA5 data during 1995–2017 were utilized to evaluate the performance of the CNN. Our CNN shows the best performance in a recent 10-year period (2008–2017), showing a significantly improved level of NCWT prediction skill with a correlation skill of 0.65 at a 5-month lead time, which is much better than the forecast skill of the state-of-the-art dynamic seasonal prediction system. Heat map analysis was used to explore the possible physical mechanisms associated with the NCWT anomaly from the perspective of the CNN;the results showed that the SST over the Northeast Pacific is highly relevant to NCWT prediction. The Northeast Pacific warming in the boreal summer is related to the development of the El Niño event in the coming winter, which may induce NCWT anomalies by atmospheric teleconnection. Climate model experiments support the role of Northeast Pacific warming in the boreal summer on NCWT. The improved capability for prediction from using the CNN may help to establish the energy policy for the coming winter and reduce the economic losses from extremely cold in North China.

EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-325435


ACE2, the putative receptor for the novel coronavirus (2019-nCoV), played an important role in cell entry of 2019-nCoV. However, it is not yet clear what cell types within the human body express ACE2. Here, a systematic analysis was undertaken using published single cell datasets. In total, our study analyzed 229652 cells, from five different organs, derived from 88 donors. The top ACE2 expressing cells include proximal tubule cells in the kidney and enterocytes in the intestine. Other major ACE2 expressing cells in the kidney include podocytes, intercalated cells and endothelial cells. Our results offer a comprehensive atlas of ACE2 expression at the single cell level and unravel the enormous potential targets of 2019-nCoVinfection beyond the lung.

Chin J Integr Med ; 26(7): 527-532, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-1343028


OBJECTIVE: To seek potential Chinese herbal medicine (CHM) for the treatment of coronavirus disease 2019 (COVID-19) through the molecular docking of the medicine with SARS-CoV-2 3CL hydrolytic enzyme and the angiotensin converting enzyme II(ACE2) as receptors, using computer virtual screening technique, so as to provide a basis for combination forecasting. METHODS: The molecular docking of CHM with the SARS-Cov-2 3CL hydrolase and the ACE2 converting enzyme, which were taken as the targets, was achieved by the Autodock Vina software. The CHM monomers acting on 3CLpro and ACE2 receptors were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, the active ingredients were selected, and the key CHMs and compounds were speculated. Based on the perspective of network pharmacology, the chemical-target network was constructed, and the functional enrichment analysis of gene ontology and the pathway enrichment analysis of Kyoto encyclopedia of genes and genomes were carried out by DAVID to speculate about the mechanism of action of the core drug pairs. RESULTS: There are 6 small molecule compounds that have the optimal binding energy with the two target proteins. Among 238 potential anti-COVID-19 herbs screened in total, 16 kinds of CHM containing the most active ingredients, and 5 candidate anti-COVID-19 herbs that had been used in high frequency, as well as a core drug pair, namely, Forsythiae Fructus-Lonicerae Japonicae Flos were selected. CONCLUSION: The core drug pair of Forsythiae Fructus-Lonicerae Japonicae Flos containing multiple components and targets is easy to combine with 3CLpro and ACE2, and exerts an anti-COVID-19 pneumonia effect through multi-component and multi-target, and plays the role of anti-COVID-19 pneumonia in multi-pathway.

Betacoronavirus/metabolism , Computer Simulation , Coronavirus Infections/drug therapy , Drugs, Chinese Herbal/therapeutic use , Molecular Docking Simulation , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/drug therapy , Angiotensin-Converting Enzyme 2 , COVID-19 , Gene Ontology , Humans , Pandemics , SARS-CoV-2 , Thermodynamics
JCI Insight ; 6(14)2021 07 22.
Article in English | MEDLINE | ID: covidwho-1320462


Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a pandemic. Severe disease is associated with dysfunction of multiple organs, but some infected cells do not express ACE2, the canonical entry receptor for SARS-CoV-2. Here, we report that the C-type lectin receptor L-SIGN interacted in a Ca2+-dependent manner with high-mannose-type N-glycans on the SARS-CoV-2 spike protein. We found that L-SIGN was highly expressed on human liver sinusoidal endothelial cells (LSECs) and lymph node lymphatic endothelial cells but not on blood endothelial cells. Using high-resolution confocal microscopy imaging, we detected SARS-CoV-2 viral proteins within the LSECs from liver autopsy samples from patients with COVID-19. We found that both pseudo-typed virus enveloped with SARS-CoV-2 spike protein and authentic SARS-CoV-2 virus infected L-SIGN-expressing cells relative to control cells. Moreover, blocking L-SIGN function reduced CoV-2-type infection. These results indicate that L-SIGN is a receptor for SARS-CoV-2 infection. LSECs are major sources of the clotting factors vWF and factor VIII (FVIII). LSECs from liver autopsy samples from patients with COVID-19 expressed substantially higher levels of vWF and FVIII than LSECs from uninfected liver samples. Our data demonstrate that L-SIGN is an endothelial cell receptor for SARS-CoV-2 that may contribute to COVID-19-associated coagulopathy.

COVID-19 , Capillaries , Cell Adhesion Molecules/metabolism , Endothelial Cells , Lectins, C-Type/metabolism , Liver/blood supply , Lymphatic Vessels , Receptors, Cell Surface/metabolism , SARS-CoV-2/physiology , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Capillaries/metabolism , Capillaries/pathology , Capillaries/virology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Endothelial Cells/virology , Gene Expression Profiling/methods , Humans , Liver/pathology , Lymphatic Vessels/metabolism , Lymphatic Vessels/pathology , Lymphatic Vessels/virology , Spike Glycoprotein, Coronavirus , Virus Internalization
Am J Infect Control ; 49(7): 900-906, 2021 07.
Article in English | MEDLINE | ID: covidwho-986923


BACKGROUND: Based on the status of the COVID-19 global pandemic, there is an urgent need to systematically evaluate the effectiveness of wearing masks to protect public health from COVID-19 infection. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement was consulted to report this systematic review. We conducted a systematic review and meta-analysis to evaluate the effectiveness of using face masks to prevent the spread of SARS-CoV-2. Relevant articles were retrieved from PubMed, Web of Science, ScienceDirect, Cochrane Library, and Chinese National Knowledge Infrastructure, VIP (Chinese) database. There were no language restrictions. This study was registered with PROSPERO under the number CRD42020211862. RESULTS: A total of 6 studies were included, involving 4 countries, after a total of 5,178 eligible articles were searched in databases and references. In general, wearing a mask was associated with a significantly reduced risk of COVID-19 infection (OR = 0.38, 95% CI: 0.21-0.69, I2 = 54.1%). For the healthcare workers group, masks were shown to have a reduced risk of infection by nearly 70%. Sensitivity analysis showed that the results were robust. CONCLUSIONS: The results of this systematic review and meta-analysis support the conclusion that wearing a mask could reduce the risk of COVID-19 infection. Robust randomized trials are needed in the future to better provide evidence for these interventions.

COVID-19 , Masks , Humans , SARS-CoV-2
J Public Health (Oxf) ; 43(4): e656, 2021 12 10.
Article in English | MEDLINE | ID: covidwho-597591

Elbow Joint , Elbow , Hand , Humans
Travel Med Infect Dis ; 36: 101751, 2020.
Article in English | MEDLINE | ID: covidwho-401273


BACKGROUND: Conflicting recommendations exist related to whether masks have a protective effect on the spread of respiratory viruses. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was consulted to report this systematic review. Relevant articles were retrieved from PubMed, Web of Science, ScienceDirect, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI), VIP (Chinese) database. RESULTS: A total of 21 studies met our inclusion criteria. Meta-analyses suggest that mask use provided a significant protective effect (OR = 0.35 and 95% CI = 0.24-0.51). Use of masks by healthcare workers (HCWs) and non-healthcare workers (Non-HCWs) can reduce the risk of respiratory virus infection by 80% (OR = 0.20, 95% CI = 0.11-0.37) and 47% (OR = 0.53, 95% CI = 0.36-0.79). The protective effect of wearing masks in Asia (OR = 0.31) appeared to be higher than that of Western countries (OR = 0.45). Masks had a protective effect against influenza viruses (OR = 0.55), SARS (OR = 0.26), and SARS-CoV-2 (OR = 0.04). In the subgroups based on different study designs, protective effects of wearing mask were significant in cluster randomized trials and observational studies. CONCLUSIONS: This study adds additional evidence of the enhanced protective value of masks, we stress that the use masks serve as an adjunctive method regarding the COVID-19 outbreak.

Betacoronavirus , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Disease Transmission, Infectious/prevention & control , Masks , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/transmission , COVID-19 , Coronavirus Infections/virology , Humans , Pneumonia, Viral/virology , Respiratory Protective Devices/virology , SARS-CoV-2