•The immunogenicity of hemagglutinin (HA) of newly emerged influenza A virus H7N9 need to be known.•Inactivated whole-virion containing HA and NA of H7N9 in the PR8 background was evaluated.•Antibody ...titers were assessed in different doses of HA alone, or with alum, and/or with a booster.•Immunization could produce neutralizing antibodies in mice and rhesus macaques.•Mice received sera from immunized animals could be protected from lethal challenge of H7N9 virus.
We evaluated the immunogenicity of hemagglutinin (HA) in the context of inactivated H7N9/AH/1/13-PR8 whole-virion. At 4weeks after immunization with 15μg HA, mice produced hemagglutination inhibition (HI) titers of 1:192 and neutralizing antibodies of 1:317. Aluminum hydroxide (alum), or a booster immunization, or both increased HI to 1:768, 1:384, 1:896 and neutralizing antibodies to 1:1868, 1:2302, 1:10,000, respectively. Macaques generated HI of 1:190 or 1:360 and virus neutralizing titers of 1:280 or 1:658 at 3weeks after immunization with HA alone or with alum. Sera from immunized mice and macaques protected mice from infection of A/Anhui/1/2013 (H7N9), suggesting an H7N9 vaccine is immunologically feasible.
Dear Editor,Rift Valley fever(RVF)is an anthropozoonosis caused by Rift Valley fever virus(RVFV).RVFV belongs to the Phlebovirus genus in the family Bunyaviridae,which is circulating among ...ruminants.Human infection with RVFV is generally asymptomatic,however,minority of patients develop severe RVF diseases like encephalitis or hemorrhagic complications, with a fatality rate up to 50%.
Virus-specific T cells play essential roles in protection against multiple virus infections, including SARS-CoV and MERS-CoV. While SARS-CoV-2-specific T cells have been identified in COVID-19 ...patients, their role in the protection of SARS-CoV-2-infected mice is not established. Here, using mice sensitized for infection with SARS-CoV-2 by transduction with an adenovirus expressing the human receptor (Ad5-hACE2), we identified SARS-CoV-2-specific T cell epitopes recognized by CD4+ and CD8+ T cells in BALB/c and C57BL/6 mice. Virus-specific T cells were polyfunctional and were able to lyse target cells in vivo. Further, type I interferon pathway was proved to be critical for generating optimal antiviral T cell responses after SARS-CoV-2 infection. T cell vaccination alone partially protected SARS-CoV-2-infected mice from severe disease. In addition, the results demonstrated cross-reactive T cell responses between SARS-CoV and SARS-CoV-2, but not MERS-CoV, in mice. Understanding the role of the T cell response will guide immunopathogenesis studies of COVID-19 and vaccine design and validation.
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Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has spread worldwide through person-to-person contact, causing a public health emergency of international concern. At ...present, there is no specific antiviral treatment recommended for SARS-CoV-2 infection. Liu Shen capsule (LS), a traditional Chinese medicine, has been proven to have a wide spectrum of pharmacological properties, such as anti-inflammatory, antiviral and immunomodulatory activities. However, little is known about the antiviral effect of LS against SARS-CoV-2. Herein, the study was designed to investigate the antiviral activity of SARS-CoV-2 and its potential effect in regulating the host’s immune response. The inhibitory effect of LS against SARS-CoV-2 replication in Vero E6 cells was evaluated by using the cytopathic effect (CPE) and plaque reduction assay. The number of virions of SARS-CoV-2 was observed under transmission electron microscope after treatment with LS. Proinflammatory cytokine expression levels upon SARS-CoV-2 infection in Huh-7 cells were measured by real-time quantitative PCR assays. The results showed that LS could significantly inhibit SARS-CoV-2 replication in Vero E6 cells, and reduce the number of virus particles and it could markedly reduce pro-inflammatory cytokines (TNF-α, IL-6, IL-1β, IL-8, CCL-2/MCP-1 and CXCL-10/IP-10) production at the mRNA levels. Moreover, the expression of the key proteins in the NF-κB/MAPK signaling pathway was detected by western blot and it was found that LS could inhibit the expression of p-NF-κB p65, p-IκBα and p-p38 MAPK, while increasing the expression of IκBα. These findings indicate that LS could inhibit SARS-CoV-2 virus infection via downregulating the expression of inflammatory cytokines induced virus and regulating the activity of NF-κB/MAPK signaling pathway in vitro, making its promising candidate treatment for controlling COVID-19 disease.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has extensively and rapidly spread in the world, causing an outbreak of acute infectious pneumonia. However, no specific antiviral drugs ...or vaccines can be used. Phillyrin (KD-1), a representative ingredient of Forsythia suspensa, possesses anti-inflammatory, anti-oxidant, and antiviral activities. However, little is known about the antiviral abilities and mechanism of KD-1 against SARS-CoV-2 and human coronavirus 229E (HCoV-229E).
The study was designed to investigate the antiviral and anti-inflammatory activities of KD-1 against the novel SARS-CoV-2 and HCoV-229E and its potential effect in regulating host immune response in vitro.
The antiviral activities of KD-1 against SARS-CoV-2 and HCoV-229E were assessed in Vero E6 cells using cytopathic effect and plaque-reduction assay. Proinflammatory cytokine expression levels upon infection with SARS-CoV-2 and HCoV-229E infection in Huh-7 cells were measured by real-time quantitative PCR assays. Western blot assay was used to determine the protein expression of nuclear factor kappa B (NF-κB) p65, p-NF-κB p65, IκBα, and p-IκBα in Huh-7 cells, which are the key targets of the NF-κB pathway.
KD-1 could significantly inhibit SARS-CoV-2 and HCoV-229E replication in vitro. KD-1 could also markedly reduce the production of proinflammatory cytokines (TNF-α, IL-6, IL-1β, MCP-1, and IP-10) at the mRNA levels. Moreover, KD-1 could significantly reduce the protein expression of p-NF-κB p65, NF-κB p65, and p-IκBα, while increasing the expression of IκBα in Huh-7 cells.
KD-1 could significantly inhibit virus proliferation in vitro, the up-regulated expression of proinflammatory cytokines induced by SARS-CoV-2 and HCoV-229E by regulating the activity of the NF-кB signaling pathway. Our findings indicated that KD-1 protected against virus attack and can thus be used as a novel strategy for controlling the coronavirus disease 2019.
Chikungunya virus (CHIKV) has caused large outbreaks worldwide in recent years, especially on the islands of the Indian Ocean and India. The virus is transmitted by mosquitoes (Aedes aegypti), which ...are widespread in China, with an especially high population density in southern China. Analyses of full-length viral sequences revealed the acquisition of a single adaptive mutation providing a selective advantage for the transmission of CHIKV by this species. No outbreaks due to the local transmission of CHIKV have been reported in China, and no cases of importation were detected on mainland China before 2008. We followed the spread of imported CHIKV in southern China and analyzed the genetic character of the detected viruses to evaluate their potential for evolution.
The importation of CHIKV to mainland China was first detected in 2008. The genomic sequences of four of the imported viruses were identified, and phylogenetic analysis demonstrated that the sequences were clustered in the Indian Ocean group; however, seven amino acid changes were detected in the nonstructural protein-coding region, and five amino acid changes were noted in the structural protein-coding regions. In particular, a novel substitution in E2 was detected (K252Q), which may impact the neurovirulence of CHIKV. The adaptive mutation A226V in E1 was observed in two imported cases of chikungunya disease.
Laboratory-confirmed CHIKV infections among travelers visiting China in 2008 were presented, new mutations in the viral nucleic acids and proteins may represent adaptive mutations for human or mosquito hosts.
•We study the effect of CEO's financial experience on earnings management.•We distinguish between accrual-based earnings management and real earnings management.•The results show that CEOs with ...financial experience tend to do less real earnings management.•No evidence shows that CEOs with financial experience do either more or less accrual-based earnings management.
We study whether Chinese CEOs with financial experience engage in more earnings management or less earnings management than those without such experience. In doing so, we distinguish between accrual-based earnings management and real earnings management. Overall, we find that CEOs with financial experience tend to do less real earnings management, while we find no evidence that they do either more or less accrual-based earnings management. Our findings tend to confirm that CEOs with financial experience provide more precise earnings information and higher quality financial statements.
Traditional methods for identifying gear faults typically require a substantial number of faulty samples, which in reality are challenging to obtain. To tackle this challenge, this paper introduces a ...sophisticated approach for intelligent gear fault identification, utilizing discrete wavelet decomposition and an enhanced convolutional neural network (CNN) optimized for scenarios with limited sample data. Initially, the features of the sample signal are extracted and enhanced using discrete wavelet decomposition. Subsequently, the refined signal is transformed into a two-dimensional image through a Markov transition field, preparing it for improved two-dimensional CNN training. Finally, the refined network model is applied to assess the gear fault dataset, achieving a training accuracy of 97% and a classification accuracy of 88.33%. This demonstrates the method’s feasibility and effectiveness in identifying gear faults with limited sample data.