Corrigendum to: Emergence and evolution of highly pathogenic porcine epidemic diarrhea virus by natural recombination of a low pathogenic vaccine isolate and a highly pathogenic strain in the spike gene.

[This corrects the article DOI: 10.1093/ve/veaa049.].

Emergence and evolution of highly pathogenic porcine epidemic diarrhea virus by natural recombination of a low pathogenic vaccine isolate and a highly pathogenic strain in the spike gene.

Outbreaks of a new variant of porcine epidemic diarrhea virus (PEDV) at the end of 2010 have raised interest in the mutation and recombination of PEDV. A PEDV strain (CN/Liaoning25/2018) isolated from a clinical outbreak of piglet diarrhea contained a 49-bp deletion in the ORF3 gene. This deletion is considered a genetic characteristic of low pathogenic attenuated vaccine strains. However, CN/Liaoning25/2018 was highly pathogenic. Complete genome sequencing, identity analysis, phylogenetic tree construction, and recombination analysis showed that this virus was a recombinant strain containing the Spike (S) gene from the highly pathogenic CN/GDZQ/2014 strain and the remaining genomic regions from the low pathogenic vaccine isolate SQ2014. Histopathology and immunohistochemistry results confirmed that this strain was highly pathogenic and indicated that intestinal epithelial cell vacuolation was positively correlated with the intensity and density of PEDV antigens. A new natural recombination model for PEDV was identified. Our results suggest that new highly pathogenic recombinant strains in the field may be generated by recombination between low pathogenic attenuated live PEDV vaccines and pathogenic circulating PEDV strains. Our findings also highlight that the 49-bp deletion of the ORF3 gene in low pathogenic attenuated vaccine strains will no longer be a reliable standard to differentiate the classical vaccine attenuated from the field strains.

A novel porous aspirin-loaded (GO/CTS-HA)n nanocomposite films: Synthesis and multifunction for bone tissue engineering.

A novel porous graphene oxide (GO)/chitosan (CTS)-hydroxyapatite (HA) nanocomposite film was successfully prepared for the first time by combining layer-by-layer (LBL) assembly technology with biomimetic mineralization method. The LBL technology was used to control the thickness of film as well as induce the biomimetic mineralization of biocompatible HA. The obtained (GO/CTS-HA)n film provided ideal platform for the proliferation of mouse mesenchymal stem cells (mMSCs). The pore size in the film is about 300nm, and the porous architecture made the film have high aspirin loading efficiency. Also the accumulated loading dosage could be adjusted by the film thickness, and the sustained release of aspirin could ensure well anti-inflammatory effect. The above advantages may alleviate the pain of patients and give the better environment for bone regeneration. This multifunctional aspirin-loaded (GO/CTS-HA)n film provided an inspiration for the synthesis of novel porous inorganic/biomacromolecule nanocomposite films as the biocoatings applied in bone tissue engineering.