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• Viral isolation, plaque purification, and propagation of PDCoV HNZK-02 on ST and LLC-PK cells. • Phylogenetic analysis of genome sequences of the cell-culture adapted-PDCoV strain HNZK-02. • mRNAs identification in PDCoV-infected ST cells by RNA-Seq. • PDCoV induces inflammatory response through NF-κB signaling passway. Porcine deltacoronavirus (PDCoV), an emerging porcine enteropathogenic coronavirus, causes acute watery diarrhea and vomiting in piglets. Here, we isolated a strain of PDCoV from intestinal content of a piglet with severe watery diarrhea on a farm located in Henan Province, named PDCoV strain HNZK-02. Subsequently, the complete genomes of cell-cultured PDCoV HNZK-02 passage 5 and 15 were sequenced and analyzed. There was a continuous 3-nucleotide deletion and 7 amino acid changes in S genes when compared with the other reported PDCoVs. RNA sequencing (RNA-seq)-based transcriptome analysis was used to quantitatively identify differentially expressed genes after PDCoV infection in ST cells. In total, 523 differentially expressed genes (DEGs) were identified, including 62 upregulated genes and 457 downregulated genes. The 62 upregulated genes were associated with TNF signaling pathway, cytokine-cytokine receptor interaction, Toll-like receptor signaling pathway, IL-17 signaling, chemokine signaling pathway and NF-κB signaling pathway. The significant expressing changed genes, including three antiviral genes (Mx1, OASL, OAS1) and three inflammatory chemokine related genes (CCL5, CXCL8, CXCL10) were further validated using quantitative real-time RT-PCR (qRT-PCR) assay. It showed the consistent expression patterns of the candidate genes with those from RNA-seq. Our results demonstrated that PDCoV infection activates NF-κB signaling pathway and leads to the expression of inflammatory factors, which may be related to TLRs but TLR2 is not a critical factor.In general, these results can help us to confirm the molecular regulation mechanism and also provide us a comprehensive resource of PDCoV infection. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) has become a global concern and is especially severe in China. To effectively and reliably provide AMR data, we developed a new high-throughput real-time PCR assay based on microfluidic dynamic technology, and screened multiple AMR genes in broiler fecal samples. A high-throughput real-time PCR system with an new designed integrated fluidic circuit assay were performed AMR gene detection. A total of 273 broiler fecal samples collected from two geographically separated farms were screened AMR genes. The new assay with limits of detection ranging from 40.9 to 8,000 copies/reaction. The sensitivity rate, specificity rate, positive predictive value, negative predictive value and correct indices were 99.30%, 98.08%, 95.31%, 99.79%, and 0.9755, respectively. Utilizing this assay, we demonstrate that AMR genes are widely spread, with positive detection rates ranging from 0 to 97.07% in 273 broiler fecal samples. bla CTX-M , bla TEM , mcr -1, fex A, cfr, optr A, and int l1 showed over 80% prevalence. The dissemination of AMR genes was distinct between the two farms. We successfully established a new high-throughput real-time PCR assay applicable to AMR gene surveillance from fecal samples. The widespread existence of AMR genes detected in broiler farms highlights the current and severe problem of AMR. [ABSTRACT FROM AUTHOR]

• A disease occurrence characterized by fever and rash was monitored in China. • The etiological and epidemiological investigation was initiated. • We proved that a novel species of genus Ehrlichia was its pathogen. • We named the new species as " Candidatus Ehrlichia erythraense". From March to June 2021, the reported number of clinically diagnosed endemic typhus in Anhui and Hubei provinces of China nearly increased four-fold compared with the monthly average numbers in last 5 years. An etiological and epidemiological investigation was initiated. The clinical specimens from the reported patients and the potential vector ticks were collected for molecular and serological detection, as well as cell culturing assay to identify the potential pathogen. Polymerase chain reaction and sequence analysis of rrs and groEL showed that the pathogen from these patients was Ehrlichia sp., isolated from Haemaphysalis longicornis attached to these patients. The phylogenetic analysis based on 39 Ehrlichia genomes suggested that it should be taxonomically classified as a novel species, tentatively named " Candidatus Ehrlichia erythraense". A total of 19 of 106 cases were confirmed as Candidatus Ehrlichia erythraense infections by polymerase chain reaction, sequencing, and/or serological tests. The most frequent symptoms were fever (100%), rashes (100%), asthenia (100%), anorexia (100%), and myalgia (79%). The occurrence of the disease presenting with fever and rashes in Anhui and Hubei provinces was caused by a novel species of the genus Ehrlichia ; physicians need to be aware of this newly-discovered pathogen to ensure appropriate testing, treatment, and regional surveillance. [ABSTRACT FROM AUTHOR]

Aims: Recently, chemoresistance has been recognized as an obstacle in the treatment of gastric cancer (GC). The aim of this study was to investigate the biological functions and underlying mechanisms of propofol in GC chemoresistance., Main Methods: CCK-8 assay, flow cytometry and immunofluorescent staining were performed to assess the IC 50 concentration, cell apoptosis and autophagy activity of cisplatin in both GC chemosensitive cells (SGC7901) and chemoresistant cells (SGC7901/CDDP). The expression pattern of MALAT1 in GC cells was detected by qRT-PCR. The shRNAs and overexpressing plasmids were employed for the loss or gain-of-function. Dual-luciferase reporter assay was subjected to verify the binding relationship between MALAT1 and miR-30e. Besides, ATG5 mRNA and protein levels were determined using qRT-PCR and western blot analysis. Furthermore, GC xenograft mice model was established to validate the in vitro findings., Key Findings: Chemoresistant GC cells presented higher IC 50 of cisplatin, increased autophagy activity and stronger expression of MALAT1. The application of propofol promoted cell apoptosis and reduced the activity of autophagy through downregulating MALAT1. Silencing of MALAT1 inhibited chemo-induced autophagy, whereas MALAT1 overexpression promoted autophagy in GC cells. Mechanistic researches demonstrated that MALAT1 could bind with miR-30e to regulate ATG5 expression, thus causing the suppression of autophagy. In vivo GC xenograft model treated with both propofol and cisplatin also showed significantly decreased tumor size and weight, which was enhanced by knockdown of MALAT1., Significance: Altogether, our study revealed a novel mechanism of propofol of lncRNA MALAT1/miR-30e/ATG5 mediated autophagy-related chemoresistance in GC, casting new lights on the understanding of propofol., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)