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1.
Front Med (Lausanne) ; 8: 654754, 2021.
Article in English | MEDLINE | ID: covidwho-1638235

ABSTRACT

Purpose: To summarize the imaging results of COVID-19 pneumonia and develop a computerized tomography (CT) screening procedure for patients at our institution with malignant tumors. Methods: Following epidemiological investigation, 1,429 patients preparing to undergo anti-tumor-treatment underwent CT scans between February 17 and April 16, 2020. When CT findings showed suspected COVID-19 pneumonia after the supervisor radiologist and the thoracic experience radiologist had double-read the initial CT images, radiologists would report the result to our hospital infection control staff. Further necessary examinations, including the RT-PCR test, in the assigned hospital was strongly recommended for patients with positive CT results. The CT examination room would perform sterilization for 30 min to 1 h. If the negative results of any suspected COVID-19 pneumonia CT findings were identified, the radiologists would upload the results to our Hospital Information Systems and inform clinicians within 2 h. Results: Fifty (0.35%, 50/1,429) suspected pneumonia cases, including 29 males and 21 females (median age: 59.5 years old; age range 27-79 years), were identified. A total of 34.0% (17/50) of the patients had a history of lung cancer and 54.0 (27/50) underwent chemotherapy or targeted therapy. Forty-six patients (92.0%) had prior CT scans, and 35 patients (76.1%) with suspected pneumonia were newly seen (median interval time: 62 days). Sub-pleura small patchy or strip-like lesions most likely due to fibrosis or hypostatic pneumonia and cluster of nodular lesions were the two main signs of suspected cases on CT images (34, 68.0%). Twenty-seven patients (54.0%) had, at least once, follow-up CT scan (median interval time: 18.0 days). Only one patient had an increase in size (interval time: 8 days), the immediately RT-PCR test result was negative. Conclusion: CT may be useful as a screening tool for COVID-19 based on imaging features. But the differential diagnosis between COVID-19 and other pulmonary infection and/or non-infectious disease is very difficult due to its overlapping imaging features.The confirmed diagnosis of the COVID-19 infection should be based on the etiologic eventually. The cancer patients at a low-incidence area would continue treatment by screening carefully before admission.

2.
Cell ; 2022.
Article in English | ScienceDirect | ID: covidwho-1611650

ABSTRACT

SUMMARY COVID-19 pandemic continues worldwide with many variants arising, especially those of variants of concern (VOCs). A recent VOC, Omicron (B.1.1.529), which obtains a large number of mutations in the receptor-binding domain (RBD) of the spike protein, has risen to intense scientific and public attention. Here we studied the binding properties between the human receptor ACE2 (hACE2) and the VOC RBDs and resolved the crystal and cryo- EM structures of the Omicron RBD-hACE2 complex, as well as the crystal structure of Delta RBD-hACE2 complex. We found that, unlike Alpha, Beta and Gamma, Omicron RBD binds to hACE2 at a similar affinity compared to that of the prototype RBD, which might be due to compensation of multiple mutations for both immune escape and transmissibility. The complex structures of Omicron-hACE2 and Delta-hACE2 reveal the structural basis of how RBD-specific mutations bind to hACE2.

3.
Frontiers in medicine ; 8, 2021.
Article in English | EuropePMC | ID: covidwho-1610493

ABSTRACT

Purpose: To summarize the imaging results of COVID-19 pneumonia and develop a computerized tomography (CT) screening procedure for patients at our institution with malignant tumors. Methods: Following epidemiological investigation, 1,429 patients preparing to undergo anti-tumor-treatment underwent CT scans between February 17 and April 16, 2020. When CT findings showed suspected COVID-19 pneumonia after the supervisor radiologist and the thoracic experience radiologist had double-read the initial CT images, radiologists would report the result to our hospital infection control staff. Further necessary examinations, including the RT-PCR test, in the assigned hospital was strongly recommended for patients with positive CT results. The CT examination room would perform sterilization for 30 min to 1 h. If the negative results of any suspected COVID-19 pneumonia CT findings were identified, the radiologists would upload the results to our Hospital Information Systems and inform clinicians within 2 h. Results: Fifty (0.35%, 50/1,429) suspected pneumonia cases, including 29 males and 21 females (median age: 59.5 years old;age range 27–79 years), were identified. A total of 34.0% (17/50) of the patients had a history of lung cancer and 54.0 (27/50) underwent chemotherapy or targeted therapy. Forty-six patients (92.0%) had prior CT scans, and 35 patients (76.1%) with suspected pneumonia were newly seen (median interval time: 62 days). Sub-pleura small patchy or strip-like lesions most likely due to fibrosis or hypostatic pneumonia and cluster of nodular lesions were the two main signs of suspected cases on CT images (34, 68.0%). Twenty-seven patients (54.0%) had, at least once, follow-up CT scan (median interval time: 18.0 days). Only one patient had an increase in size (interval time: 8 days), the immediately RT-PCR test result was negative. Conclusion: CT may be useful as a screening tool for COVID-19 based on imaging features. But the differential diagnosis between COVID-19 and other pulmonary infection and/or non-infectious disease is very difficult due to its overlapping imaging features.The confirmed diagnosis of the COVID-19 infection should be based on the etiologic eventually. The cancer patients at a low-incidence area would continue treatment by screening carefully before admission.

6.
Front Cell Infect Microbiol ; 11: 813645, 2021.
Article in English | MEDLINE | ID: covidwho-1581376

ABSTRACT

[This corrects the article DOI: 10.3389/fcimb.2021.720357.].

7.
iScience ; 24(12): 103426, 2021 Dec 17.
Article in English | MEDLINE | ID: covidwho-1509907

ABSTRACT

Glycosylation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein mediates viral entry and immune escape. While glycan site is determined by viral genetic code, glycosylation is completely dependent on host cell post-translational modification. Here, by producing SARS-CoV-2 virions from various host cell lines, viruses of different origins with diverse spike protein glycan patterns were revealed. Binding affinities to C-type lectin receptors (CLRs) DC&L-SIGN differed in the different glycan pattern virions. Although none of the CLRs supported viral productive infection, viral trans&cis-infection mediated by the CLRs were substantially changed among the different virions. Specifically, trans&cis-infection of virions with a high-mannose structure (Man5GlcNAc2) at the N1098 glycan site of the spike postfusion trimer were markedly enhanced. Considering L-SIGN co-expression with ACE2 on respiratory tract cells, our work underlines viral epigenetic glycosylation in authentic viral infection and highlights the attachment co-receptor role of DC&L-SIGN in SARS-CoV-2 infection and prevention.

9.
Non-conventional in English | Social Science Open Access Repository, Grey literature | ID: grc-747882

ABSTRACT

Health and science controversies surrounding Covid-19 pandemic have been politicized by state actors to manipulate international relations and politics. China is no exception. Using a package of communication tactics, the Chinese government has been engaging in an English-language information campaign to create an “Us vs US” world during the pandemic on social media. While the world is scrutinizing the accuracy of and the intention behind the information disseminated by China’s state actors, this commentary urges scholars to also focus on the influence of such information on global audiences, as well as on global power dynamics.

10.
Front Cell Infect Microbiol ; 11: 720357, 2021.
Article in English | MEDLINE | ID: covidwho-1497025

ABSTRACT

SARS-coronavirus 2 (SARS-CoV-2), pathogen of coronavirus disease 2019 (COVID-19), is constantly evolving to adapt to the host and evade antiviral immunity. The newly emerging variants N501Y.V1 (B.1.1.7) and N501Y.V2 (B.1.351), first reported in the United Kingdom and South Africa respectively, raised concerns due to the unusually rapid global spread. The mutations in spike (S) protein may contribute to the rapid spread of these variants. Here, with a vesicular stomatitis virus (VSV)-based pseudotype system, we demonstrated that the pseudovirus bearing N501Y.V2 S protein has higher infection efficiency than pseudovirus with wildtype (WT) and D614G S protein. Moreover, pseudovirus with N501Y.V1 or N501Y.V2 S protein has better thermal stability than WT and D614G, suggesting these mutations of variants may increase the stability of SARS-CoV-2 S protein and virion. However, the pseudovirus bearing N501Y.V1 or N501Y.V2 S protein has similar sensitivity to inhibitors of protease and endocytosis with WT and D614G. These findings could be of value in preventing the spread of virus and developing drugs for emerging SARS-CoV-2 variants.


Subject(s)
COVID-19 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , Mutation , Spike Glycoprotein, Coronavirus/genetics
11.
Genomics and Applied Biology ; 39(8):3886-3889, 2020.
Article in Chinese | GIM | ID: covidwho-1497993

ABSTRACT

COVID-19 patients carrying SARS-CoV-2 virus are highly infectious. Effective isolation and protection in hospitals are effective measures for medical staff to avoid infection and cross infection among patients. Meanwhile, SARS-CoV-2 infection can lead to the injury of important systems and parts of the body in COVID-19 patients and even death. Cytokine release syndrome(CRS) is a common cause of death in COVID-19 patients. Therefore, standardized and effective nursing program has a very important role for stopping the spread and spread of SARS-CoV-2. This study included five aspects: ward layout and environmental control, infection management and protection, clinical symptom classification, observation and nursing, psychological support and nutrition management, detection of vital signs and prognosis of patients, which systematically elaborated the clinical protection and nursing of covid-19, in order to provide reference for the early diagnosis and treatment of the disease, improve the cure rate, reduce the death rate and avoid hospital infection.

12.
Chinese Journal of Zoonoses ; 37(8):688-697, 2021.
Article in Chinese | GIM | ID: covidwho-1497431

ABSTRACT

Through bioinformatics, we systematically predicted and analyzed the structure and function of TMPRSS2, a key protease used by SARS-CoV-2 to invade host cells, thus providing a reliable reference for the research on the protein and the development of its inhibitors. We used ProtParam, Protscale, SignalP 4.0 Server, SecretomeP 2.0 server, TMHMM Server v. 2.0, SOPMA, SWISS-MODEL, MEGA-X and other software to predict the structure, function, evolution, biological processes and other aspects of the TMPRSS2 gene and protein. We comprehensively analyzed and demonstrated the results obtained with each program. TMPRSS2 protein was found to be a hydrophilic protein composed of 492 amino acids. It has a transmembrane helix structure and is a non-classical secreted protein. The expression of TMPRSS2 protein in the prostate was particularly abundant, and it has abundant post-translational modification sites. TMPRSS2 protein has a total of three superfamily conserved domains, and the amino acid sequence after the 100th position is relatively conserved. We report comprehensive prediction and analysis of the structure and function of the TMPRSS2 protein. From the perspective of bioinformatics, our results verify its characteristics as a serine protease and provide a possible mechanistic explanation for its participation in SARS-CoV-2 invasion of hosts. This work should facilitate further experiments and research related to TMPRSS2.

13.
Physica A ; 588: 126558, 2022 Feb 15.
Article in English | MEDLINE | ID: covidwho-1487921

ABSTRACT

The outbreak of coronavirus disease 2019 (COVID-19) threatens the health and safety of all humanity. This disease has a prominent feature: the presymptomatic and asymptomatic viral carriers can spread the disease. It is crucial to estimate the impact of this undetected transmission on epidemic outbreaks. Currently, disease-related information has been widely disseminated by the mass media. To investigate the impact of both individuals and mass media information dissemination on the epidemic spreading, we establish a new UAU-SEIR (Unaware-Aware-Unaware-Susceptible-Exposed-Infected-Recovered) model with mass media on two-layer multiplex networks. In the model, E-state individuals denote asymptomatic infections, and a single node connecting to all individuals denotes the mass media. In this work, we use the Microscopic Markovian Chain Approach (MMCA) to derive the epidemic threshold. Comparing the MMCA theoretical results with Monte Carlo (MC) simulations, we find that the MMCA has a good consistency with MC simulations. In addition, we also analyze the impact of model parameters on epidemic spreading and epidemic threshold. The results show that reducing the proportion of asymptomatic infections, accelerating the dissemination of information between individuals and the dissemination of information via the mass media can effectively inhibit the epidemic spreading and raise the epidemic threshold.

14.
Nat Commun ; 12(1): 6103, 2021 10 20.
Article in English | MEDLINE | ID: covidwho-1475296

ABSTRACT

Multiple SARS-CoV-2 variants of concern (VOCs) have been emerging and some have been linked to an increase in case numbers globally. However, there is yet a lack of understanding of the molecular basis for the interactions between the human ACE2 (hACE2) receptor and these VOCs. Here we examined several VOCs including Alpha, Beta, and Gamma, and demonstrate that five variants receptor-binding domain (RBD) increased binding affinity for hACE2, and four variants pseudoviruses increased entry into susceptible cells. Crystal structures of hACE2-RBD complexes help identify the key residues facilitating changes in hACE2 binding affinity. Additionally, soluble hACE2 protein efficiently prevent most of the variants pseudoviruses. Our findings provide important molecular information and may help the development of novel therapeutic and prophylactic agents targeting these emerging mutants.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/virology , Protein Interaction Domains and Motifs/genetics , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Amino Acid Sequence , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/isolation & purification , Angiotensin-Converting Enzyme 2/ultrastructure , Animals , Cell Line, Tumor , Crystallography, X-Ray , HEK293 Cells , Humans , Molecular Dynamics Simulation , Mutation , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/ultrastructure , SARS-CoV-2/genetics , Sf9 Cells , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/isolation & purification , Spike Glycoprotein, Coronavirus/ultrastructure , Spodoptera , Surface Plasmon Resonance , Virus Attachment , Virus Internalization
15.
Int J Health Plann Manage ; 2021 Oct 19.
Article in English | MEDLINE | ID: covidwho-1473843

ABSTRACT

OBJECTIVES: This study assesses the status of public service motivation and explains it's the positive association with public cooperation during the initial stage of the COVID-19 crisis. Moreover, potential causes of Chinese citizens' public service motivation have been explored. METHODS: A cross-sectional survey of 30 provinces in China was conducted using an online questionnaire. The study was conducted in February 2020 during the initial stage of the COVID-19 pandemic. Socio-demographic factors, public service motivation, public satisfaction, public confidence, and public cooperation were assessed using questionnaires. Hierarchical multiple regression was used to identify clusters of interrelationships among public service motivation, public satisfaction, public confidence, and public cooperation among Chinese citizens. RESULTS: We found that participants' public satisfaction with COVID-19-related public services had a positive association with public confidence (B = 0.456, p < 0.001) and public service motivation (B = 0.177, p < 0.001). Moreover, public confidence regarding anti-COVID-19 measures had a positive influence on public service motivation (B = 0.308, p < 0.001) while mediating the relationship between public satisfaction and public service motivation. Public service motivation were positively associated with public cooperation with anti-COVID-19 measures during the initial stage of the COVID-19 pandemic. CONCLUSION: A considerably high level of public service motivation among Chinese citizens appeared during the initial stage of the COVID-19 pandemic, resulting in an increase in public cooperation. Moreover, the findings prove that a high degree of satisfaction with the government's initiatives regarding anti-COVID-19 measures encouraged greater personal public service motivation in respondents by increasing confidence in governmental responses and performance.

16.
Front Public Health ; 9: 690525, 2021.
Article in English | MEDLINE | ID: covidwho-1436029

ABSTRACT

Background: Understanding the levels of health literacy among different groups is essential for better public health interventions targeting specific subgroups of the population. Additionally, this article explores the prevalence and influencing factors of the health literacy levels of different age groups during the COVID-19 epidemic. Methods: Multistage stratified cluster random sampling and the Probability Proportion to Size (PPS) method were used to select permanent residents aged 15-69 in Chongqing (54,706) for the questionnaire survey. The survey period is from July 2019 and July 2020. Single-factor analysis and logistic regression models were used to study the relationship between demographics, socioeconomic factors, other independent covariates, and health literacy. Results: The health literacy levels of residents declined with age, and there were significant differences in health literacy levels between age groups (χ2 = 3332.884, P < 0.05). As far as the factors affecting health literacy level are concerned, high education and high income are the protective factors for health literacy level for residents of all ages. For adolescents (OR = 1.383, 95% CI: 1.217-1.571), young adults (OR = 1.232, 95% CI = 1.117-1.358), and middle-aged people (OR = 1.096, 95% CI = 1.017-1.182), residence in rural areas was a protective factor. In terms of the dimensions of health literacy, in particular, elderly health literacy in 2020 in Scientific Health Concepts, Safety and First Aid, Basic Medical Care decreased significantly compared with 2019. Conclusions: For adolescents, young adults, middle-aged people, to solve the problem of urban and rural health quality gap, we should not only use the geographical division, but also consider the social population and socio-economic differences. For the elderly, the following four dimensions of health literacy need to be paid more attention than those of other age: Basic Knowledge and Concepts, Scientific Health Concepts, Safety and First Aid, and Basic Medical Care. A lack of knowledge on the prevention and treatment of chronic diseases is the main reason for the recent decline in health literacy. And the health literacy among residents in major public health emergencies is needed.


Subject(s)
COVID-19 , Health Literacy , Adolescent , Aged , China/epidemiology , Humans , Middle Aged , SARS-CoV-2 , Surveys and Questionnaires , Young Adult
17.
Applied Economics ; : 1-13, 2021.
Article in English | Taylor & Francis | ID: covidwho-1426944
19.
Biochim Biophys Acta Mol Basis Dis ; 1867(12): 166260, 2021 12 01.
Article in English | MEDLINE | ID: covidwho-1377661

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection-induced inflammatory responses are largely responsible for the death of novel coronavirus disease 2019 (COVID-19) patients. However, the mechanism by which SARS-CoV-2 triggers inflammatory responses remains unclear. Here, we aimed to explore the regulatory role of SARS-CoV-2 spike protein in infected cells and attempted to elucidate the molecular mechanism of SARS-CoV-2-induced inflammation. METHODS: SARS-CoV-2 spike pseudovirions (SCV-2-S) were generated using the spike-expressing virus packaging system. Western blot, mCherry-GFP-LC3 labeling, immunofluorescence, and RNA-seq were performed to examine the regulatory mechanism of SCV-2-S in autophagic response. The effects of SCV-2-S on apoptosis were evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), Western blot, and flow cytometry analysis. Enzyme-linked immunosorbent assay (ELISA) was carried out to examine the mechanism of SCV-2-S in inflammatory responses. RESULTS: Angiotensin-converting enzyme 2 (ACE2)-mediated SCV-2-S infection induced autophagy and apoptosis in human bronchial epithelial and microvascular endothelial cells. Mechanistically, SCV-2-S inhibited the PI3K/AKT/mTOR pathway by upregulating intracellular reactive oxygen species (ROS) levels, thus promoting the autophagic response. Ultimately, SCV-2-S-induced autophagy triggered inflammatory responses and apoptosis in infected cells. These findings not only improve our understanding of the mechanism underlying SARS-CoV-2 infection-induced pathogenic inflammation but also have important implications for developing anti-inflammatory therapies, such as ROS and autophagy inhibitors, for COVID-19 patients.


Subject(s)
COVID-19/metabolism , Inflammation/metabolism , Spike Glycoprotein, Coronavirus/immunology , Animals , Apoptosis/immunology , Autophagy/physiology , Cell Line , Chlorocebus aethiops , Endothelial Cells/metabolism , HEK293 Cells , Humans , Inflammation/immunology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , SARS-CoV-2/pathogenicity , Signal Transduction/immunology , Spike Glycoprotein, Coronavirus/metabolism , TOR Serine-Threonine Kinases/metabolism , Vero Cells
20.
Emerg Infect Dis ; 27(9): 2288-2293, 2021 09.
Article in English | MEDLINE | ID: covidwho-1369628

ABSTRACT

We estimated the symptomatic, PCR-confirmed secondary attack rate (SAR) for 2,382 close contacts of 476 symptomatic persons with coronavirus disease in Yichang, Hubei Province, China, identified during January 23-February 25, 2020. The SAR among all close contacts was 6.5%; among close contacts who lived with an index case-patient, the SAR was 10.8%; among close-contact spouses of index case-patients, the SAR was 15.9%. The SAR varied by close contact age, from 3.0% for those <18 years of age to 12.5% for those >60 years of age. Multilevel logistic regression showed that factors significantly associated with increased SAR were living together, being a spouse, and being >60 years of age. Multilevel regression did not support SAR differing significantly by whether the most recent contact occurred before or after the index case-patient's onset of illness (p = 0.66). The relatively high SAR for coronavirus disease suggests relatively high virus transmissibility.


Subject(s)
COVID-19 , SARS-CoV-2 , Adolescent , Child , China/epidemiology , Humans , Incidence , Logistic Models
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