Impact of COVID-19 pandemic on the etiology and characteristics of community-acquired pneumonia among children requiring bronchoalveolar lavage in northern China (preprint)

Background: To investigate the etiology and clinical characteristics of community-acquired pneumonia (CAP) among children requiring bronchoalveolar lavage (BAL) and analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on the pathogen spectrum and clinical manifestations. Methods: Children <14 years old hospitalized with CAP requiring BLA were enrolled between February 2019 to January 2020 and August 2021 to July 2022. Multiplex reverse transcription polymerase chain reaction (mRT-PCR) was used for pathogen detection. The demographic and clinical characteristics were compared between different pathogen-type infection groups, and before and during the COVID-19 pandemic. Results: Pathogen was detected in 91.66% (1363/1487) children. Mycoplasma pneumoniae, adenovirus and human rhinovirus were the most frequently detected pathogens. The frequency of detection of virus infections and co-infections was decreased during the pandemic, but the detection of atypical bacterial infections was increased. The clinical manifestations and the results of CT scans and fiberoptic bronchoscopy showed a significant difference between different types of pathogen infection, and lung inflammation was reduced during the COVID-19 pandemic compared with before the pandemic. Conclusions: M. pneumoniae infection might be the greatest pediatric disease burden leading to CAP in northern China. Wearing masks and social distancing in public places during the COVID-19 pandemic effectively reduced the transmission of respiratory viruses, but it did not reduce the infection rate of M. pneumoniae. In addition, these interventions significantly reduced lung inflammation in children compared with before the pandemic.

Federated Learning Enabled Credit Priority Task Processing for Transportation Big Data

Due to the epidemic COVID-19 spread and Intelligent Transportation System (ITS) development, investigators are now to conduct their research over the generated Transportation Big Data (TBD) in many critical areas, such as medical supplies, food supplies, as well as logistics supplies. At present, Vehicular Edge Computing (VEC) is an emerging paradigm to integrate resources from vehicles, road-site units, base stations, and cloud center to promote the performance of TBD tasks scheduling and running. In this paper, we design a three-layered TBD task processing architecture with a federated learning mechanism for credit priority-based task scheduling and running. In our design, we consider the efficiency of task offloading and misbehavior attack problems simultaneously. We propose a vehicular federated learning framework combined with Multi-Layer Perceptron (MLP) credit measurement, which can preserve the privacy of vehicles and obtain the related features for vehicular credit prediction. We also propose a task offloading algorithm to solve the optimization problem for credit priority task offloading between edge computing servers and vehicles. The proposed solution can prioritize tasks and assign sufficient resources for reliable and active task requesters. Experimental results expose that the proposed mechanism outperforms the state-of-the-art solutions when considering efficiency and attack simultaneously for TBD tasks scheduling and running.

In vitro and in vivo anti-HMPV activity of JH001 isolated from Chinese medicinal herbs

OBJECTIVE Human metapneumovirus（h MPV） is semblable to respiratory syncytial virus（RSV） which causes respiratory infections typically characterized by cough, runny nose, fever, and nasal congestion but sometimes progressing to bronchiolitis and pneumonia. Whereas, there is no corresponding drug to inhabit the virus. Studies of new compounds with potential anti-HMPV activity could produce clinical value. Chinese herbal medicine played a great role during COVID-19, therefore we choose some small molecular（JH001） extracted from botany to investigate therapeutic effect on h MPV and the underlying mechanisms. METHODS In this study, 16 HBE cells were used as a model to explore in vitro antiviral effect. Cytotoxicity assays were performed before the antiviral tests, cell viability of 16 HBE cells handled by different concentration of JH001 was estimated by Cell Counting Kit-8（CCK-8）. Then RT-q PCR, immunofluorescence, and flow cytometer were used to test the viral titer after cells infected with h MPV. Eventually, 6-8 weeks mice were infected intranasally with 60 μL of h MPV, the control group was treated with 0.9% saline water, other groups were administered with JH001 and ribavirin, then the lung virus titer and protective effect in lung were judged. RESULTS The obtained JH001 exhibited no cytotoxicity to 16 HBE cells during 6.25-200 μmol · L-1. RT-QPCR demonstrated that JH001 showed obvious inhabitation to the viral replication and showed great significance compared with saline. And fluorescence exhibited distinct decrease of h MPV-N protein, flow cytometer results showed that MFI decrease evidently. Significant reduction of N-gene expression was observed in those mice treated with JH001 compared with saline group,which indicated that JH001 probably had protective and therapeutic effect on viral replication. CONCLUSION This study illustrated that JH001 might be a promising option for small molecular against h MPV and JH001 might be worthy of further development and used as a potential therapeutic strategy for other respiratory viruses in the future.

The proportion and effect of corticosteroid therapy for patients with COVID-19 infection: a systematic review and meta-analysis (preprint)

Objectives: COVID-19 remains a global challenge. Corticosteroids are a group of anti-inflammatory and suppressive immune response drugs that are widely used in the treatment of COVID-19, especially when it presents with viral pneumonia. Comprehensive reviews investigating the comparative proportion and efficacy of corticosteroid use are scarce. Therefore, we conducted a systematic review and meta-analysis of clinical trials to evaluate the proportion and efficacy of corticosteroid use for the treatment of COVID-19.Methods: We conducted a comprehensive literature review of PubMed, EMBASE, the Cochrane Controlled Trials Registry, and the China Academic Journal Network Publishing Database for relevant trials on glucocorticoid therapy in COVID-19 patients. Outcome measures were the proportion of patients administered corticosteroids, viral clearance and mortality. Effect size was reported as weighted mean differences (WMDs) for continuous outcomes and odds ratios (ORs) for dichotomous outcomes with associated 95% confidence intervals (CIs).Results: Forty-three trials involving 6603 patients were included. The meta-analysis demonstrated that the proportion of COVID-19 patients who received corticosteroids was significantly lower than that of patients who did not receive corticosteroids. In addition, our meta-analysis demonstrated no significant difference in the proportions of severe and nonsevere patients who were administered corticosteroids. We also performed subgroup analyses stratified by severity, indicating that the proportion of patients administered corticosteroids was significantly higher among intensive care unit (ICU) patients than among non-ICU patients. The results of our meta-analysis indicated that corticosteroid treatment significantly delayed the viral clearance time. Finally, our meta-analysis demonstrated no significant difference between the use of corticosteroids for COVID-19 patients who died and those who survived. This result indicated that mortality was not correlated with corticosteroid therapy.Conclusion: The proportion of COVID-19 patients who received corticosteroids was significantly lower than that of patients who did not receive corticosteroids. Corticosteroid use in subjects with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections delayed virus clearance and did not convincingly improve survival;therefore, corticosteroids should be used with caution in the treatment of COVID-19.