A hybrid model for daily air quality index prediction and its performance in the face of impact effect of COVID-19 lockdown.

Accurate and dependable air quality forecasting is critical to environmental and human health. However, most methods usually aim to improve overall prediction accuracy but neglect the accuracy for unexpected incidents. In this study, a hybrid model was developed for air quality index (AQI) forecasting, and its performance during COVID-19 lockdown was analyzed. Specifically, the variational mode decomposition (VMD) was employed to decompose the original AQI sequence into some subsequences with the parameters optimized by the Whale optimization algorithm (WOA), and the residual sequence was further decomposed by the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN). On this basis, a deep learning method bidirectional long short-term memory coupled with added time filter layer and attention mechanism (TFA-BiLSTM) was employed to explore the latent dynamic characteristics of each subsequence. This WOA-VMD-CEEMDAN-TFA-BiLSTM hybrid model was used to forecast AQI values for four cities in China, and results verified that the accuracy of the hybrid model outperformed other proposed models, achieving R2 values of 0.96-0.97. In addition, the improvement in MAE (34.71-49.65%) and RMSE (32.82-48.07%) were observed over single decomposition-based model. Notably, during the epidemic lockdown period, the hybrid model had significant superiority over other proposed models for AQI prediction.

Artificial Lipid Biomembranes for Full-Length SARS-CoV-2 Receptor.

The angiotensin-converting enzyme 2 (ACE2), as a functional receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is essential for assessing potential hosts and treatments. However, many studies are based on its truncated version but not full-length structure. Indeed, a single transmembrane (TM) helix presents in the full-length ACE2, influencing its interaction with SARS-CoV-2. Therefore, synthesis of the full-length ACE2 is an urgent requirement. Here, cell-free membrane protein synthesis systems (CFMPSs) are constructed for full-length membrane proteins. MscL is screened as a model among ten membrane proteins based on their expression and solubility. Next, CFMPSs are constructed and optimized based on natural vesicles, vesicles with four membrane proteins removed or two chaperonins added, and 37 types of nanodiscs. They all increase membrane protein solubility to over 50%. Finally, the full-length ACE2 of 21 species are successfully expressed with yields between 0.4 and 0.9 mg mL-1 . The definite functional differences from the truncated version suggest that the TM region affects ACE2's structure and function. CFMPSs can be extended to more membrane proteins, paving the way for further applications.

Analysis of the anxiety level and influencing factors during the coronavirus disease 2019 epidemic among the parents of students in China.

Background: Due to the outbreak of Coronavirus Disease 2019, there has been a significant impact on the mental health of parents. However, no detailed study on the mental health status of parents has been conducted to date. Methods: This study was a cross-sectional used a whole-group random sampling method to conduct an online questionnaire survey with 102,883 parents in Guangdong Province, China, April 25, 2020 and May 14, 2020. Anxiety was assessed by using the Generalized Anxiety Disorder tool (GAD-7). Potential factors of anxiety were estimated using univariate analysis and multivariate logistic regression analysis by SPSS 22.0 statistical software. Results: Among the total 94,705 parents who have completed the questionnaire survey (92.05% response rate). The incidence of anxiety was 23.77%. Parents' anxiety symptoms are more likely to be caused by female family roles, higher levels of education, unemployed or jobless employment status, children not being an only child, and children having negative attitudes toward online courses. Conclusions: Our research shows that most parents experienced mild anxiety during the Coronavirus Disease 2019 epidemic. Our findings provide strong evidence for investigating and focusing on the mental health of this population during the COVID-19 epidemic. Therefore, governments and healthcare departments at all levels should actively provide psychological counseling services to relieve their anxiety symptoms.

ZDHHC11 Suppresses Zika Virus Infections by Palmitoylating the Envelope Protein.

Zika virus (ZIKV) is an RNA-enveloped virus that belongs to the Flavivirus genus, and ZIKV infections potentially induce severe neurodegenerative diseases and impair male fertility. Palmitoylation is an important post-translational modification of proteins that is mediated by a series of DHHC-palmitoyl transferases, which are implicated in various biological processes and viral infections. However, it remains to be investigated whether palmitoylation regulates ZIKV infections. In this study, we initially observed that the inhibition of palmitoylation by 2-bromopalmitate (2-BP) enhanced ZIKV infections, and determined that the envelope protein of ZIKV is palmitoylated at Cys308. ZDHHC11 was identified as the predominant enzyme that interacts with the ZIKV envelope protein and catalyzes its palmitoylation. Notably, ZDHHC11 suppressed ZIKV infections in an enzymatic activity-dependent manner and ZDHHC11 knockdown promoted ZIKV infection. In conclusion, we proposed that the envelope protein of ZIKV undergoes a novel post-translational modification and identified a distinct mechanism in which ZDHHC11 suppresses ZIKV infections via palmitoylation of the ZIKV envelope protein.

A comparative study of virus nucleic acid re-positive and non-re-positive patients infected with SARS-CoV-2 Delta variant strain in the Ningxia Hui Autonomous Region.

Objective: This study aimed to provide a basis for epidemic prevention and control measures as well as the management of re-positive personnel by analyzing and summarizing the characteristics of re-positive patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant infections discharged from a hospital in the Ningxia Hui Autonomous Region in 2021. Methods: This case-control study included a total of 45 patients with Delta variant infections diagnosed in the Fourth People's Hospital of the Ningxia Hui Autonomous Region between October 17 and November 28, 2021. Based on the nucleic acid test results post-discharge, the patients were dichotomized into re-positive and non-re-positive groups. Based on the time of the first re-positive test, the re-positive group was further divided into <7 and ≥7 days groups to compare their clinical characteristics and explore the possible influencing factors of this re-positivity. Results: Of the 45 total patients, 16 were re-positive (re-positivity rate: 35.6%), including four patients who were re-positive after 2 weeks (re-positivity rate: 8.8%). The median time of the first re-positive after discharge was 7 days (IQR: 14-3). The re-positive group was younger than the non-re-positive group (35 vs. 53, P < 0.05), had a higher proportion of patients who were not receiving antiviral therapy (56.2 vs. 17.2%, P < 0.05). The median CT value of nucleic acid in the re-positive group was considerably greater than that at admission (36.7 vs. 22.6 P < 0.05). The findings demonstrated that neutralizing antibody treatment significantly raised the average IgG antibody level in patients, particularly in those who had not received COVID-19 vaccine (P < 0.05). The median lowest nucleic acid CT value of the ≥7 days group during the re-positive period and the immunoglobulin G (IgG) antibody level at discharge were lower than those in the <7 days group (P < 0.05). When compared to the non-positive group, patients in the ≥7 days group had a higher median virus nucleic acid CT value (27.1 vs. 19.2, P < 0.05) and absolute number of lymphocytes at admission (1,360 vs. 952, P < 0.05), and a lower IgG antibody level at discharge (P < 0.05). Conclusions: In conclusion, this study found that: (1) The re-positivity rate of SARS-CoV-2 Delta variant infection in this group was 35.6%, while the re-positivity rate was the same as that of the original strain 2 weeks after discharge (8.0%). (2) Young people, patients who did not use antiviral therapy or had low IgG antibody levels at discharge were more likely to have re-positive. And the CT value of nucleic acid at the time of initial infection was higher in re-positive group. We speculated that the higher the CT value of nucleic acid at the time of initial infection, the longer the intermittent shedding time of the virus. (3) Re-positive patients were asymptomatic. The median CT value of nucleic acid was > 35 at the re-positive time, and the close contacts were not detected as positive. The overall transmission risk of re-positive patients is low.

Dynamic blockchain adoption for freshness-keeping in the fresh agricultural product supply chain

During COVID-19, the explosive growth of demand for fresh agricultural products on E-commerce platform has increased the difficulty of maintaining the greenness and freshness in delivery. The traditional cold chain delivery is effective in keeping greenness, but its information asymmetry makes the freshness-keeping activities unable to be regulated, which may lead to the supply chain members giving up their freshness-keeping efforts. Can the blockchain technology effectively solve these problems? We consider a fresh agricultural product supply chain consisting of a supplier and an E-commerce platform (retailer). The retailer is responsible for the wholesale and sales of fresh agricultural products, and determines the blockchain adoption degree and advertising effort. The supplier is responsible for delivering fresh agricultural products to consumers, and determines the greenness investment and freshness-keeping effort. Based on the traditional and blockchain-based fresh agricultural product supply chain, we discuss the dynamic optimization of freshness-keeping effort, advertising effort, and blockchain adoption degree. Results show that the supplier will give up the freshness-keeping effort after receiving the wholesale funds in the traditional fresh agricultural product supply chain, which will naturally worsen the fresh agricultural products. When adopting blockchain technology, the supplier continues to make the freshness-keeping effort in delivery. And five specific settings are proved that blockchain is effective in maintaining freshness. But two other specific settings are determined that it is not suited for adopting blockchain. In addition, compared with the traditional fresh agricultural product supply chain, blockchain adoption can effectively reduce the freshness-keeping effort, advertising investment and goodwill for achieving the same profit margin level, and will not affect the greenness investment decision of the supplier. Our research can provide some insights into the cold chain logistics management of fresh blockchain.

Parental psychosocial factors predicting adolescents' psychological adjustment during the surging and remission periods of COVID-19 in China: A longitudinal study.

BACKGROUND: Parents play a critical role in adolescents' psychological adjustment, especially in stress response. Few studies have investigated parental impact on adolescents' psychological adjustment in the pandemic. The longitudinal study examined how parental psychosocial factors at the surging period of the pandemic (T1) in China predicted adolescents' anxiety and depression concurrently and at the remission periods three (T2) and six months (T3) later. METHODS: Middle and high school students and their parents from three schools in Shanghai, China, completed online surveys on March 10, 2020 (T1), June 16, 2020 (T2), and Sep 25, 2020 (T3). Adolescents' anxiety/depression levels were assessed by matching self- and parent-reports at T1, T2, T3, and parents reported their psychological state (emotion and psychopathology), pandemic response (appraisal and coping), and perceived social support (PSS) at T1. RESULTS: Parental positive/negative emotions, anxiety, depression, control-appraisal, forward- and trauma-focus coping style and PSS were all significantly related to their children's anxiety/depression at T1. All factors, except coping style, predicted adolescents' anxiety/depression at T2 and T3, even after controlling for T1 adjustment levels. Parental positive emotion and depression had the strongest impact on adolescents' adjustment. LIMITATIONS: Some participants didn't complete the surveys at later time points, and the participants were only recruited in Shanghai. CONCLUSIONS: The study found that parents' psychosocial factors played a pivotal role on adolescents' psychological adjustment during COVID-19, highlighting the need to provide help to parents who were suffering from potential psychological distress.

A protein vaccine with Alum/c-GAMP/poly(I:C) rapidly boosts robust immunity against SARS-CoV-2 and variants of concern.

Adjuvants are important components in vaccines to increase the immunogenicity of proteins and induce optimal immunity. In this study, we designed a novel ternary adjuvant system Alum + c-GAMP + poly(I:C) with STING agonist 3,3'-c-GAMP (c-GAMP) and TLR3 agonist poly(I:C) co-adsorbed on the conventional adjuvant aluminum gel (Alum), and further constructed an S1 protein vaccine. Two doses of vaccination with the ternary adjuvant vaccine were sufficient to induce a balanced Th1/Th2 immune response and robust humoral and cellular immunity. Additionally, the ternary adjuvant group had effective neutralizing activity against live virus SARS-CoV-2 and pseudovirus of all variants of concern (alpha, beta, gamma, delta and omicron). These results indicate that the ternary adjuvants have a significant synergistic effect and can rapidly trigger potent immune responses; the combination of the ternary adjuvant system with S1 protein is a promising COVID-19 vaccine candidate.

RBD conjugate vaccine with a built-in TLR1/2 agonist is highly immunogenic against SARS-CoV-2 and variants of concern.

The coronavirus 2019 (COVID-19) pandemic is causing serious impacts in the world, and safe and effective vaccines and medicines are the best methods to combat the disease. The receptor-binding domain (RBD) of the SARS-CoV-2 spike protein plays a key role in interacting with the angiotensin-converting enzyme 2 (ACE2) receptor, and is regarded as an important target of vaccines. Herein, we constructed the adjuvant-protein conjugate Pam3CSK4-RBD as a vaccine candidate, in which the N-terminal of the RBD was site-selectively oxidized by transamination and conjugated with the TLR1/2 agonist Pam3CSK4. This demonstrated that the conjugation of Pam3CSK4 significantly enhanced the anti-RBD antibody response and cellular response. In addition, sera from the Pam3CSK4-RBD immunized group efficiently inhibited the binding of the RBD to ACE2 and protected cells from SARS-CoV-2 and four variants of concern (alpha, beta, gamma and delta), indicating that this adjuvant strategy could be one of the effective means for protein vaccine development.

Traditional Chinese medicine for treatment of Coronavirus disease 2019: a review

Since late December in 2019, the coronavirus disease 2019 has received extensive attention for its widespread prevalence. A number of clinical workers and researchers have made great efforts to understand the pathogenesis and clinical characteristics and develop effective drugs for treatment. However, no effective drugs with antiviral effects on severe acute respiratory syndrome coronavirus 2 have been discovered currently. Traditional Chinese medicine (TCM) has gained abundant experience in the treatment of infectious diseases for thousands of years. In this review, the authors summarized the clinical outcome, pathogensis and current application of TCM on coronavirus disease 2019. Further, we discussed the potential mechanisms and the future research directions of TCM against severe acute respiratory syndrome coronavirus 2.

Efficient Bayesian inference of fully stochastic epidemiological models with applications to COVID-19.

Epidemiological forecasts are beset by uncertainties about the underlying epidemiological processes, and the surveillance process through which data are acquired. We present a Bayesian inference methodology that quantifies these uncertainties, for epidemics that are modelled by (possibly) non-stationary, continuous-time, Markov population processes. The efficiency of the method derives from a functional central limit theorem approximation of the likelihood, valid for large populations. We demonstrate the methodology by analysing the early stages of the COVID-19 pandemic in the UK, based on age-structured data for the number of deaths. This includes maximum a posteriori estimates, Markov chain Monte Carlo sampling of the posterior, computation of the model evidence, and the determination of parameter sensitivities via the Fisher information matrix. Our methodology is implemented in PyRoss, an open-source platform for analysis of epidemiological compartment models.

Network pharmacology studies on the effect of chai-ling decoction in Coronavirus disease 2019

Background: Chai-Ling decoction (CLD), derived from a modification of Xiao-Chai-Hu (XCH) decoction and Wu-Ling-San (WLS) decoction, has been used to treat the early-stage of coronavirus disease 2019 (COVID-19). However, the mechanisms of CLD in COVID-19 remain unknown. In this study, the potential mechanisms of CLD in COVID-19 were preliminarily investigated based on network pharmacology and molecular docking method.

Axial Chiral Binaphthoquinone and Perylenequinones from the Stromata of Hypocrella bambusae Are SARS-CoV-2 Entry Inhibitors.

A new axial chiral binaphtoquinone, hypocrellone (1), and a new perylenequinone, hypomycin F (2), were isolated from the stromata of Hypocrella bambusae, together with five known compounds, 3-7. The structures of 1 and 2 were assigned by spectroscopic and HRESIMS data analyses. The axial chirality of 1 was determined by electronic circular dichroism data analysis, and the absolute configurations of 2 and 3 were determined by X-ray crystallography. The axial chirality of 7 was determined by UV-induced photooxidation from 4. Compounds 1, 4, and 5 showed inhibitory activity against pseudotyped SARS-CoV-2 infection in 293T-ACE2 cells with IC50 values of 0.17, 0.038, and 0.12 µM. Compounds 4 and 5 were also active against live SARS-CoV-2 infection with EC50 values of 0.22 and 0.21 µM, respectively. Further cell-cell fusion assays, surface plasmon resonance assays, and molecular docking studies revealed that 4 and 5 could bind with the receptor-binding domain of SARS-CoV-2 S protein to prevent its interaction with human angiotensin-converting enzyme II receptor. Our results revealed that 4 and 5 are potential SARS-CoV-2 entry inhibitors.

Comparison of clinical and serological features of RT-PCR positive and negative COVID-19 patients.

BACKGROUND: In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) began in Wuhan, China, and led to a global epidemic. We aimed to compare the clinical and serological features of COVID-19 patients with positive and negative reverse transcriptase polymerase chain reaction (RT-PCR) tests. METHODS: This was a retrospective cohort study conducted from 9 February to 4 April 2020. COVID-19 patients at Leishenshan Hospital in Wuhan, China (125 total cases; 87 RT-PCR positive and 38 RT-PCR negative) were included. COVID-19 serology was assessed by colloidal gold assay. All cases were analyzed for demographic, clinical, and serological features. RESULTS: There were no significant differences in most demographic features, clinical symptoms, complications or treatments of RT-PCR positive and negative COVID-19 patients. Serum IgM/IgG was positive in 82 (94%) and 33 (87%) RT-PCR positive and negative cases, respectively. IgM was detectable as early as 3 days after symptom onset and was undetectable 60 days after symptom onset. By contrast, IgG could be detected only 10 days after symptom onset and reached its peak 60 days after symptom onset. CONCLUSIONS: Serological tests performed during the appropriate time window of disease progression could be valuable auxiliary methods to RT-PCR in COVID-19 patients.

Prevalence and Associated Factors for Depressive Symptomatology in Chinese Adults During COVID-19 Epidemic.

Background: The coronavirus disease 2019 (COVID-19) has been rapidly transmitted worldwide, which contributed to various psychological problems (such as fear, depression, and anxiety) among the general population in China. The purpose of this study is to investigate the prevalence and associated factors of depressive symptoms among Chinese adults. Methods: A cross-sectional study of Chinese adults was conducted during 17-29 February 2020. Symptoms of depression were assessed using the Center for Epidemiologic Studies Depression scale (CES-D). Results: A total of 3,399 respondents were included in the analysis. It was observed that 14.2% (481/3,399) of the participants were screened positive for depressive symptoms. In a multivariate logistic regression analysis, older age (OR = 0.98; 95% CI, 0.97-0.99), smoking (OR = 1.57; 95% CI, 1.10-2.26), self-rated health (good: OR = 0.49; 95% CI, 0.37-0.66; fairly: OR = 0.60; 95% CI, 0.45-0.80), having greater support scores (OR = 0.95; 95% CI, 0.94-0.96), knowledge about the main symptom of COVID-19 (very clearly: OR = 0.58; 95% CI, 0.42-0.79; relatively clearly: OR = 0.59; 95% CI, 0.44-0.79), and staying in Wuhan within 3 months before the outbreak of epidemic (OR = 1.78; 95% CI, 1.34-2.38) were associated with depressive symptoms. Conclusion: A considerable proportion of the general population in China had depressive symptoms during the COVID-19 epidemic. Routine screening and targeted interventions for depression are needed among high-risk depressed individuals during the COVID-19 epidemic.

Management of immune checkpoint therapy for patients with cancer in the face of COVID-19.

The COVID-19 outbreak caused by SARS-CoV-2 challenges the medical system by interfering with routine therapies for many patients with chronic diseases. In patients with cancer receiving immune checkpoint inhibitors (ICIs), difficulties also arise from the incomplete understanding of the intricate interplay between their routine treatment and pathogenesis of the novel virus. By referring to previous ICI-based investigations, we speculate that ICIs themselves are not linked to high-infection risks of respiratory diseases or inflammation-related adverse effects in patients with cancer. Moreover, ICI treatment may even enhance coronavirus clearance in some patients with malignant tumor by boosting antiviral T-cell responsiveness. However, the 'explosive' inflammation during COVID-19 in some ICI-treated patients with cancer was illustrated as exuberant immunopathological damage or even death. In case of the COVID-19 immunopathogenesis fueled by ICIs, we propose a regular monitor of pathogenic T-cell subsets and their exhaustion marker expression (eg, Th17 and interleukin (IL)-6-producing Th1 subsets with surface programmed death 1 expression) to guide the usage of ICI. Here we aimed to address these considerations, based on available literature and experience from our practice, that may assist with the decision-making of ICI administration during the pandemic.

Current status and associated factors of psychological resilience among the Chinese residents during the coronavirus disease 2019 pandemic.

BACKGROUND: Since December 2019, over 4,600 deaths and 84,000 confirmed cases were reported in China because of the coronavirus disease 2019 (COVID-19) pandemic. However, there is a dearth of studies on the psychological resilience in residents. AIMS: This study aims to measure the psychological resilience of Chinese residents to reflect their psychological status as well as influencing factors during the pandemic. METHOD: We conducted a combination of stratified sampling and snowball sampling to select survey subjects. We employed the psychological resilience and influencing factor questionnaire based on the 10-item Connor and Davidson Resilience Scale (CD-RISC10) for survey. We collected data from 3,398 residents in China between 31 January and 29 February 2020. Multivariable linear stepwise regression analysis was used to determine factors associated with psychological resilience in residents. RESULTS: The mean score of psychological resilience among Chinese residents was 27.11 ± 8.45 (SD = 7.98). There were some factors significantly associated with psychological status among the Chinese residents during the COVID-19 outbreak. Residents with lower financial status, living in rural areas, unmarried, lacking fixed employment or retirement guarantees, and lacking knowledge of policies were more likely to report a lower level of psychological resilience. CONCLUSION: Health service policy makers in many countries should adopt relevant measures to improve the psychological resilience of residents during the pandemic. This includes short-term aggressive treatment, strengthening health education, and improving the awareness of residents with respect to emergency health policies. In addition, the financial status, health levels, and risk management capabilities of residents should be increased over the long term.