Publications by authors named "Qiqi Xia"

Japanese encephalitis (JE) is a zoonotic ailment from the Japanese encephalitis virus (JEV). JEV belongs to the flavivirus genus and is categorized into a solitary serotype consisting of five genetically diverse genotypes (I, II, III, IV, and V). The JEV genotype III (GIII) was the prevailing strain responsible for multiple outbreaks in countries endemic to JEV until 1990.

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African swine fever (ASF) is an acute, highly contagious, and deadly infectious disease caused by the African swine fever virus (ASFV) and has a huge impact on the pig industry. A lack of vaccines and effective therapeutic drugs has brought great challenges to the prevention and control of ASF. In this study, insect baculovirus expression system was used to express ASFV B602L protein (B602L) alone and the IgG FC-fused B602L protein (B602L-Fc), and evaluate the immune effect of B602L-Fc in mice model.

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Palmitoylation of viral proteins is crucial for host-virus interactions. In this study, we examined the palmitoylation of Japanese encephalitis virus (JEV) nonstructural protein 2A (NS2A) and observed that NS2A was palmitoylated at the C221 residue of NS2A. Blocking NS2A palmitoylation by introducing a cysteine-to-serine mutation at C221 (NS2A/C221S) impaired JEV replication and attenuated the virulence of JEV in mice.

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Article Synopsis
  • Porcine reproductive and respiratory syndrome (PRRS) is a significant disease affecting pigs, leading to reproductive issues in sows and respiratory problems in piglets, primarily caused by the PRRS virus (PRRSV).
  • A study conducted from 2017 to 2022 collected 231 samples from pig farms in Eastern China, finding a 24% positive rate for PRRSV and identifying the isolates as mostly belonging to genotype 2, with some notable genetic mutations.
  • The research highlights an increase in NADC30-like and NADC34-like strains of PRRSV, contributing valuable epidemiological data for future vaccine development and management strategies in the region.
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  • Japanese encephalitis virus genotype V (GV) emerged in 2009 in China and has spread, raising concerns about its pathogenicity and the effectiveness of existing vaccines against different JEV genotypes.* -
  • Researchers created a recombinant chimeric JEV strain by replacing structural proteins from a less virulent strain with those from the more virulent GV strain, finding that the structural proteins significantly influenced virulence and neuroinvasiveness in mice.* -
  • While vaccination with the recombinant strain provided complete protection against its progenitor, it offered only partial cross-protection against other genotypes, highlighting the need for new vaccines targeting the newly emergent GV strain.*
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  • African Swine Fever (ASF) is a highly contagious and deadly disease in pigs with up to 100% mortality and poses a major threat to the swine industry due to the absence of vaccines and effective treatments.
  • Researchers developed a new detection method for ASF by using a soluble protein called pB602L, which is highly immunogenic and can be expressed in bacteria.
  • The new indirect ELISA method demonstrated excellent specificity, sensitivity, and repeatability, making it a promising tool for monitoring and controlling ASF outbreaks in pig populations.*
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Nonstructural protein 2A (NS2A) of the Japanese encephalitis virus (JEV) contributes to viral replication and pathogenesis; however, a lack of NS2A-specific antibodies restricts studies on the underlying mechanisms. In this study, we constructed a recombinant JEV with a hemagglutinin (HA)-tagged NS2A (JEV-HA/NS2A/∆NS1') to overcome this challenge. An HA-tag was fused to the N-terminus of NS2A (HA-NS2A) at the intergenic junction between NS1 and NS2A.

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Japanese encephalitis virus (JEV) is a viral zoonosis that can cause viral encephalitis, death and disability whose primary vector is the Culex mosquito. Viral infection induces a series of antimicrobial peptide responses in mosquitoes, and the effector defensin enhances JEV replication in mosquitoes. However, the underlying mechanisms by which defensin enhances JEV are not fully understood.

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Japanese encephalitis virus (JEV) genotype I (GI) replicates more efficiently than genotype III (GIII) in birds, and this difference is considered to be one of the reasons for the JEV genotype shift. In this study, we utilized duck embryo fibroblasts and domestic ducklings as in vitro and in vivo models of a JEV amplifying avian host to identify the viral determinants of the differing replication efficiency between the GI and GIII strains in birds. GI strains induced significantly lower levels of interferon (IFN)-α and β production than GIII strains, an effect orrelated with the enhanced replication efficiency of GI strains over GIII strains.

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Background: The aim of this study was to investigate the association among biofilm formation, virulence gene expression, and antibiotic resistance in P. mirabilis isolates collected from diarrhetic animals (n = 176) in northeast China between September 2014 and October 2016.

Results: Approximately 92.

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Japanese encephalitis virus (JEV) is a zoonotic pathogen that is maintained by mosquito vectors and vertebrate hosts including birds in a natural transmission cycle. Domestic ducklings are sensitive to JEV infection, but the clinical responses of domestic ducklings to natural JEV infection are unknown. In this study, we simulated the natural JEV infection of domestic ducklings via JEV-infected mosquito bites to evaluate the pathogenicity of JEV in domestic ducklings.

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Karyopherin α4 (KPNA4) is an adaptor molecule that mediates type I interferon (IFN) production by facilitating the nuclear translocation of IFN transcription factors. Here, we cloned the duck KPNA4 (duKPNA4) gene and analyzed its involvement in type I IFN expression as well as antiviral response against Japanese encephalitis virus (JEV). The full-length duKPNA4 gene encoded a 520-amino acid protein that shared 97.

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