Production of a versatile SARS-CoV-2 main protease biosensor based on a dimerization-dependent red fluorescent protein.

we designed a functionally active Mpro biosensor based on a dimerization-dependent red fluorescent protein (ddRFP) for the evaluation of Mpro inhibitors in vitro. This study provides an affordable strategy for rapid production of a versatile ddRFP biosensor, which would be a useful tool for the measurement and quantification of Mpro inhibitors This article is protected by copyright. All rights reserved.

Clinical Characteristics of Children With COVID-19: A Meta-Analysis.

Background: With the global spread of novel coronavirus disease 2019 (COVID-19), health care systems are facing formidable challenges. Scientists are conducting studies to explore this new disease, and numerous studies have been shared. However, the number of studies on children with COVID-19 is limited, and no meta-analysis of this group has been performed. Methods: A random-effect meta-analysis was conducted to determine the characteristics of children with COVID-19, including their demographic, epidemiological, clinical, laboratory, imaging features, and outcomes. Four databases and reference lists were screened. Percentages were calculated, and pooled prevalence with 95% confidence intervals (CIs) were reported. Results: Of 195 studies, 33 were selected, and 14 (371 patients) of them were included in the meta-analysis. Then, 19 case reports (25 patients) were summarized separately. Our meta-analysis revealed that 17.4% (95% CI = 9.1-27.3) of children had asymptomatic infection. Fever (51.2%, 95% CI = 40.2-62.2) and cough (37.0%, 95% CI = 25.9-48.8) were the most frequent symptoms. The prevalence of severe or critical illness was almost 0% (95% CI = 0-1.0). The most frequent abnormal laboratory findings, in pediatric patients, were leukopenia/lymphopenia (28.9%, 95% CI = 19.5-39.2) and increased creatine kinase (20.1%, 95% CI = 1.3-49.9). Ground-glass opacity was observed in the CT scan of 53.9% (95% CI = 38.4-68.7) of children diagnosed with pneumonia. Conclusions: Children are at a lower risk of developing COVID-19 and have a milder disease than adults. However, the evidence presented in this study is not satisfactory. Further investigations are urgently needed, and our data will be continuously updated.

Protocol for high-throughput screening of SARS-CoV-2 main protease inhibitors using a robust fluorescence polarization assay.

Discovery of efficacious antiviral agents targeting SARS-CoV-2 main protease (Mpro) is of the highest importance to fight against COVID-19. Here, we describe a simple protocol for high-throughput screening of Mpro inhibitors using a robust fluorescence polarization (FP) assay. Candidate Mpro inhibitors from large compound libraries could be rapidly identified by monitoring the change of millipolarization unit value. This affordable FP assay can be modified to screen antiviral agents targeting virus protease. For complete details on the use and execution of this protocol, please refer to Li et al. (2022), Yan et al. (2021), and Yan et al. (2022c).

Protocol for high-throughput screening of SARS-CoV-2 main protease inhibitors using a robust fluorescence polarization assay

Discovery of efficacious antiviral agents targeting SARS-CoV-2 main protease (Mpro) is of the highest importance to fight against COVID-19. Here, we describe a simple protocol for high-throughput screening of Mpro inhibitors using a robust fluorescence polarization (FP) assay. Candidate Mpro inhibitors from large compound libraries could be rapidly identified by monitoring the change of millipolarization unit value. This affordable FP assay can be modified to screen antiviral agents targeting viral protease. Graphical Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

A robust high-throughput fluorescence polarization assay for rapid screening of SARS-CoV-2 papain-like protease inhibitors.

The global scourge of COVID-19 is a serious threat to public health, but effective therapies remain very limited for this disease. Therefore, the discovery of novel antiviral agents is urgently needed to fight against COVID-19. In the lifecycle of SARS-CoV-2, the causing pathogen of COVID-19, papain-like protease (PLpro) is responsible for the cleavage of polyprotein into functional units as well as immune evasion of vaccines. Hence, PLpro has been regarded as an attractive target to develop antiviral agents. Herein, we first developed a robust and simple sandwich-like fluorescence polarization (FP) screening assay for the discovery of PLpro inhibitors, and identified anacardic acid as a novel competitive inhibitor against PLpro in vitro with an IC50 value of 24.26 ± 0.4 µM. This reliable FP screening assay could provide a prospective avenue for rapid discovery of antiviral agents targeting PLpro in a large-scale screening.

Mental Health of Medical Staff During the Coronavirus Disease 2019 Pandemic: A Systematic Review and Meta-Analysis.

OBJECTIVE: This study aimed to quantify the prevalence of the adverse mental health outcomes in medical staff working in the hospital settings during the coronavirus disease 2019 (COVID-19) pandemic and explore the relative distribution of anxiety and depressive symptoms. METHODS: PubMed, EMBASE, China National Knowledge Infrastructure, WANFANG DATA, and VIP Database for Chinese Technical Periodicals were searched for articles published from January 1, 2019, to April 19, 2020. The prevalence estimates of adverse mental health symptoms in medical staff were pooled using the random-effects model. RESULTS: A total of 35 articles and data of 25,343 medical staff were used in the final analysis. The pooled prevalence estimates in medical staff during the COVID-19 pandemic were as follows (ordered from high to low): fear-related symptoms, 67% (95% confidence interval [CI] = 61%-73%); high levels of perceived stress, 56% (95% CI = 32%-79%), anxiety symptoms, 41% (95% CI = 35%-47%); insomnia, 41% (95% CI = 33%-50%); posttraumatic stress disorder symptoms, 38% (95% CI = 34%-43%); depressive symptoms, 27% (95% CI = 20%-34%); and somatic symptoms, 16% (95% CI = 3%-36%). The subgroup analysis revealed that the prevalence estimates of fear-related symptoms were consistently high. CONCLUSIONS: Medical staff during the COVID-19 epidemic have a high prevalence of adverse mental health symptoms. Data-based strategies are needed to optimize mental health of medical staff and other health care professionals during times of high demand such as the COVID-19 and other epidemics.PROSPERO Registration: CRD42020182433.

[Identifying SARS-CoV-2 main protease inhibitors by a novel sandwich-like fluorescence polarization screening assay].

SARS-CoV-2 main protease (Mpro) is responsible for polyprotein cleavage to release non-structural proteins (nsps) for viral genomic RNA replication, and its homologues are absent in human cells. Therefore, Mpro has been regarded as one of the ideal drug targets for the treatment of coronavirus disease 2019 (COVID-19). In this study, we first combined the fluorescence polarization (FP) technique with biotin-avidin system (BAS) to develop a novel sandwich-like FP screening assay for quick discovery of SARS-CoV-2 Mpro inhibitors from a natural product library. With this screening assay, anacardic acid (AA) and 1, 2, 3, 4, 6-O-pentagalloylglucose (PGG) were found to be the competitive inhibitor and mixed-type inhibitor targeting Mpro, respectively. Importantly, our results showed that the majority of the reported Mpro inhibitors are promiscuous cysteine inhibitors that are not specific to Mpro. In summary, this novel sandwich-like FP screening assay is simple, sensitive, and robust, which is ideal for large-scale screening. Natural products AA and PGG will be the promising lead compounds for generating more potent antiviral agents targeting Mpro, and the stringent hit validation at the early stage of drug discovery is urgently needed.

Epidemiological, Radiographical, and Laboratorial Characteristics of Chinese Asymptomatic Cases With COVID-19: A Systematic Review and Meta-Analysis.

The comprehensive understanding of the characteristics of asymptomatic cases are helpful for the identification and management of patients with asymptomatic COVID-19 infection. Four electronic databases were searched from December 1, 2019 to February 8, 2022 for relevant articles. Data synthesis, subgroup analysis, and sensitivity analysis were performed on the included studies. I2 and Q tests were applied to evaluate heterogeneity across studies. The risk of publication bias was assessed and visualized using a funnel plot. A total of 45 studies consisting of 2,655 patients with no symptoms at the screening point were included. Pooled results showed that in China, 65% of initial no-symptoms COVID-19 patients did not present any COVID-19-related symptom during follow-up or by end of disease course (asymptomatic infections). High proportions of initial no-symptoms COVID-19 patients (76%) and patients with asymptomatic infection (55%) had abnormal CT features at the screening point. High proportion of patients with asymptomatic infection had been detected Ig G+ (72%) and/or Ig M+ (57%) at the screening point. The chest CT scan and SARS-CoV-2-specific antibody testing could serve as effective supplementary methods to identify asymptomatic cases in the early stage of SARS-CoV-2 infection. However, the chest CT scan and the SARS-CoV-2-specific IgM and IgG testing should not replace reverse transcription-polymerase chain reaction (RT-PCR) for screening in asymptomatic patients. The combination of repeated RT-PCR, chest CT scans, and the SARS-CoV-2-specific IgM and IgG testing should be performed for those highly suspected SARS-CoV-2 infections. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier: CRD 42021261130.

Clinical Characteristics of Children With COVID-19: A Meta-Analysis

Background: With the global spread of novel coronavirus disease 2019 (COVID-19), health care systems are facing formidable challenges. Scientists are conducting studies to explore this new disease, and numerous studies have been shared. However, the number of studies on children with COVID-19 is limited, and no meta-analysis of this group has been performed. Methods: A random-effect meta-analysis was conducted to determine the characteristics of children with COVID-19, including their demographic, epidemiological, clinical, laboratory, imaging features, and outcomes. Four databases and reference lists were screened. Percentages were calculated, and pooled prevalence with 95% confidence intervals (CIs) were reported. Results: Of 195 studies, 33 were selected, and 14 (371 patients) of them were included in the meta-analysis. Then, 19 case reports (25 patients) were summarized separately. Our meta-analysis revealed that 17.4% (95% CI = 9.1-27.3) of children had asymptomatic infection. Fever (51.2%, 95% CI = 40.2-62.2) and cough (37.0%, 95% CI = 25.9-48.8) were the most frequent symptoms. The prevalence of severe or critical illness was almost 0% (95% CI = 0-1.0). The most frequent abnormal laboratory findings, in pediatric patients, were leukopenia/lymphopenia (28.9%, 95% CI = 19.5-39.2) and increased creatine kinase (20.1%, 95% CI = 1.3-49.9). Ground-glass opacity was observed in the CT scan of 53.9% (95% CI = 38.4-68.7) of children diagnosed with pneumonia. Conclusions: Children are at a lower risk of developing COVID-19 and have a milder disease than adults. However, the evidence presented in this study is not satisfactory. Further investigations are urgently needed, and our data will be continuously updated.

Mental Health of Pregnant and Postpartum Women During the Coronavirus Disease 2019 Pandemic: A Systematic Review and Meta-Analysis.

Background: Prenatal and postnatal mental disorders can exert severe adverse influences on mothers, fetuses, and children. However, the effect of the coronavirus disease 2019 (COVID-19) pandemic on the mental health of pregnant and postpartum women remains unclear. Methods: Relevant studies that were published from January 1, 2019 to September 19, 2020 were identified through the systematic search of the PubMed, EMBASE, and Web of Science databases. Quality assessment of included studies, random-effects meta-analysis, sensitivity analysis, and planned subgroup analysis were performed. Results: A total of 23 studies conducted with 20,569 participants during the COVID-19 pandemic and with 3,677 pregnant women before the COVID-19 pandemic were included. The prevalence rates of anxiety, depression, psychological distress, and insomnia among pregnant women during the COVID-19 pandemic were 37% (95% confidence interval [CI] 25-49%), 31% (95% CI 20-42%), 70% (95% CI 60-79%), and 49% (95% CI 46-52%), respectively. The prevalence of postpartum depression was 22% (95% CI 15-29%). Multigravida women and women in the first and third trimesters of pregnancy were more vulnerable than other pregnant women. The assessment of the associations between the COVID-19 pandemic and mental health problems revealed that the pooled relative risks of anxiety and depression in pregnant women were 1.65 (95% CI: 1.25-2.19) and 1.08 (95% CI: 0.80-1.46), respectively. Conclusions: The prevalence rates of mental disorders among pregnant and postpartum women during the COVID-19 pandemic were high. Timely and tailored interventions should be applied to mitigate mental problems among this population of women, especially multigravida women and women in the first and third trimesters of pregnancy.