Development of an allele-specific PCR assay for simultaneous sero-typing of avian pathogenic Escherichia coli predominant O1, O2, O18 and O78 strains.

Systemic infections by avian pathogenic Escherichia coli (APEC) are economically devastating to poultry industries worldwide. E. coli strains belonging to serotypes O1, O2, O18 and O78 are preferentially associated with avian colibacillosis.

Mechanism of Asp24 upregulation in Brucella abortus rough mutant with a disrupted O-antigen export system and effect of Asp24 in bacterial intracellular survival.

We previously showed that Brucella abortus rough mutant strain 2308 ΔATP (called the ΔrfbE mutant in this study) exhibits reduced intracellular survival in RAW264.7 cells and attenuated persistence in BALB/c mice. In this study, we performed microarray analysis to detect genes with differential expression between the ΔrfbE mutant and wild-type strain S2308.

Inhibition of Newcastle disease virus replication by lentivirus-mediated RNA interference.

Small interfering RNA (siRNA)-induced RNA degradation can specifically inhibit viral infection and has been extensively investigated for its efficacy as an antiviral therapeutic approach. In this study we constructed a lentivirus vector carrying a U6-short hairpin RNA expression cassette to express siRNAs in vero cells. The lentivirus vector also expressed an enhanced green fluorescence protein as a reporter.

Activation of the PKR/eIF2α signaling cascade inhibits replication of Newcastle disease virus.

Background: Newcastle Disease virus (NDV) causes severe and economically significant disease in almost all birds. However, factors that affect NDV replication in host cells are poorly understood. NDV generates long double-stranded RNA (dsRNA) molecules during transcription of single-stranded genomic RNA.

Characterization of the immunogenicity and pathogenicity of malate dehydrogenase in Brucella abortus.

Brucella abortus is a gram-negative, facultative intracellular pathogen that causes brucellosis, a chronic zoonotic disease resulting in abortion in pregnant cattle and undulant fever in humans. Malate dehydrogenase (MDH), a key enzyme in the tricarboxylic acid cycle, plays important metabolic roles in aerobic energy producing pathways and in malate shuttle. In this study, the MDH-encoding gene for malate dehydrogenase mdh of B.

Vibrio parahaemolyticus enolase is an adhesion-related factor that binds plasminogen and functions as a protective antigen.

Vibrio parahaemolyticus, an emerging food and waterborne pathogen, is a leading cause of seafood poisoning worldwide. Surface proteins can directly participate in microbial virulence by facilitating pathogen dissemination via interactions with host factors. Screening and identification of protective antigens is important for developing therapies against V.

In vivo-induced argininosuccinate lyase plays a role in the replication of Brucella abortus in RAW264.7 cells.

Brucellosis caused by Brucella species is a zoonotic disease with a serious impact on public health and the livestock industry. To better understand the pathogenesis of the disease, in vivo-induced antigen technology (IVIAT) was used to investigate the in vivo-induced antigens of Brucella abortus in this study. A genomic expression library of B.

[RmlA gene deletion affects biofilm formation by avian pathogenic Escherichia coli].

Objective: To characterize rmlA gene inavian pathogenic Escherichia coli (APEC).

Methods: We constructed the rmlA mutant of APEC by the Red recombination system. Then we analyzed the differences of growth, movement and biofilm formation between mutant strain and wild strain.

Honokiol, a low molecular weight natural product, prevents inflammatory response and cartilage matrix degradation in human osteoarthritis chondrocytes.

Proinflammatory cytokine interleukin-1β (IL-1β) stimulates several mediators of cartilage degradation and plays an important role in the pathogenesis of osteoarthritis (OA). Honokiol, a low molecular weight natural product isolated from the Magnolia officinalis, has been shown to possess anti-inflammatory effect. Here, we used an in vitro model of cartilage inflammation to investigate the therapeutic potential of honokiol in OA.

The siderophore-interacting protein is involved in iron acquisition and virulence of Riemerella anatipestifer strain CH3.

Riemerella anatipestifer causes epizootic infectious disease in poultry and serious economic losses especially to the duck industry. However, little is known regarding the molecular basis of its pathogenesis. The ability to acquire iron under low-iron conditions is related to the virulence of a variety of bacterial pathogens.

Autophagy benefits the replication of Newcastle disease virus in chicken cells and tissues.

Newcastle disease virus (NDV) is an important avian pathogen. We previously reported that NDV triggers autophagy in U251 glioma cells, resulting in enhanced virus replication. In this study, we investigated whether NDV triggers autophagy in chicken cells and tissues to enhance virus replication.

Effect of age on the pathogenesis of DHV-1 in Pekin ducks and on the innate immune responses of ducks to infection.

Duck hepatitis virus (DHV) affects 1-week-old but not 3-week-old ducks, and it causes a more severe disease in the younger ducks. These differences may be partially due to the host response to DHV infection. In order to understand this difference, we characterized the pathobiology of and innate immune response to DHV infection in 1-day-old (1D) and 3-week-old (3 W) ducks.

Genetic characterization of Duck Hepatitis A Viruses isolated in China.

In recent years, the spread of Duck Hepatitis A Viruses (DHAVs) has represented a serious threat and significant economic impact in duck industry of China. The sixteen reported DHAV isolates (15 DHAV-1 strains and one DHAV-3) were identified from infected ducks with clinical symptoms in China between 2009 and 2012. In the present study, the virulence of these viruses and complete sequences of the virion protein 1 (VP1) genes of the 16 DHAVs were characterized.

Microarray-based identification of differentially expressed genes in intracellular Brucella abortus within RAW264.7 cells.

Brucella spp. is a species of facultative intracellular Gram-negative bacteria that induces abortion and causes sterility in domesticated mammals and chronic undulant fever in humans. Important determinants of Brucella's virulence and potential for chronic infection include the ability to circumvent the host cell's internal surveillance system and the capability to proliferate within dedicated and non-dedicated phagocytes.

A SOE-PCR method of introducing multiple mutations into Mycoplasma gallisepticum neuraminidase.

A modified splicing with overlap extension PCR (SOE-PCR) was generated to introduce 21 TGA to TGG at Mycoplasma gallisepticum MGA_0329 gene. The recombinant protein was successfully expressed and retained neuraminidase activities, indicating that SOE-PCR is a rapid and highly efficient method of introducing multiple mutations into large M. gallisepticum genes.

Infectivity and pathogenicity of Newcastle disease virus strains of different avian origin and different virulence for mallard ducklings.

Experimental infections of Newcastle disease virus (NDV) strains of different avian origin and different virulence in mallard (Anas platyrhynchos) ducklings were undertaken to evaluate infectivity and pathogenicity of NDV for ducks and the potential role of ducks in the epidemiology of Newcastle disease (ND). Ducklings were experimentally infected with seven NDV strains, and their clinical sign, weight gain, antibody response, virus shedding, and virus distribution in tissues were investigated. The duck origin virulent strain duck/Jiangsu/JSD0812/2008 (JSD0812) and the Chinese standard virulent strain F48E8 were highly pathogenic for ducklings.

[Effect of autoinducer 2 on Riemerell antatipestifer adherence and invasion to Vero cells].

Objective: Autoinducer 2 (AI-2), used to communicate among bacterial species, regulates numerous physiological functions of bacteria. In this study, we studied the effect of AI-2 on adherence and invasion of Riemerella antatipestifer (RA) strain CH3 to Vero cells and transcriptional levels of virulence-related and metabolism-related genes were investigated.

Methods: To verify whether the adherence and invasion of CH3 was affected by AI-2, we added different concentrations of AI-2 to the cocultures of Vero cells and CH3 and then calculated adherence percentages and invasion percentages of tested groups.

[Establishment and preliminary application of a quantitative real-time PCR method for detecting the transcriptions of Th1/Th2 cytokines in RAW264.7 cells].

Objective: To establish a quantitative real-time PCR method to detect the transcriptions of Th1/Th2 cytokines in RAW264.7 cells.

Methods: The specific primers were designed according to the sequences of TNF-α, IFN-γ, IL-2, IL-4, IL-6, IL-10 and β-actin in GenBank database.

[Mutation of lambdapL/pR-cI857 system for production of bacterial ghost in Escherichia coli].

Bacterial ghost is intact envelope of Gram-negative bacteria, which is produced by the function of the lysis gene E from bacteriophage PhiX174. The expression of the lysis gene E is usually controlled by the thermosensitive lambdapL/pR-cI857 promoter. In this study, we described a mutation (T --> C) at the ninth nucleotide of the OR2 in the lambdapR promoter of the lambdapL/pR-cI857 system by overlap PCR.

Inactivation of the ABC transporter ATPase gene in Brucella abortus strain 2308 attenuated the virulence of the bacteria.

Brucella abortus is a Gram-negative, facultative intracellular bacterial pathogen of human and other animals. Brucella lipopolysaccharide has been identified as an important virulence factor. In this study, the ABC transporter ATPase gene (BAB1_0542) of B.

Targeting autophagy to enhance oncolytic virus-based cancer therapy.

Introduction: Autophagy is a conserved catabolic process crucial in maintaining cellular homeostasis. On infection, oncolytic viruses (OVs) perturb the cellular autophagy machinery in infected tumor cells both in vitro and in vivo. Currently, pharmacological modulation of autophagy in OV-infected tumor cells has been shown to augment OV-mediated antitumor effects in preclinical studies.

Development and evaluation of a trivalent Riemerella anatipestifer-inactivated vaccine.

Riemerella anatipestifer infections cause major economic losses in the duck industry. In this study, a trivalent inactivated vaccine of R. anatipestifer, including strains CH3 (serotype 1), NJ3 (serotype 2), and HXb2 (serotype 10), was developed.

[Cloning and expression of luxS and pfs and in vitro biosynthesis autoinducer 2 of avian pathogenic Escherichia coli from Anhui Province].

Objective: The LuxS/AI-2 quorum sensing (QS) system shared by Gram-positive and Gram-negative bacteria involves the production of autoinducer-2 (AI-2). In this study, the method of biosynthesis of AI-2 was established using recombinant LuxS and Pfs of avian pathogenic Escherichia coli (APEC), which will be benefit for future study of the role of AI-2 in APEC.

Methods: We investigated AI-2 production in APEC by vibrio harveyi BB170 (BB170).

Goose RIG-I functions in innate immunity against Newcastle disease virus infections.

Mammalian retinoic acid-inducible gene I (RIG-I) is a chief antiviral gene sensing viral RNA molecules including Newcastle disease virus (NDV). In this study, goose RIG-I gene (gRIG-I) was identified. The 2805 bp-long gene encodes a gRIG-I protein that exhibits 93.

The luxS gene functions in the pathogenesis of avian pathogenic Escherichia coli.

Avian pathogenic Escherichia coli (APEC) causes avian colibacillosis, the most significant infectious bacterial disease of poultry worldwide. LuxS, the product of the luxS gene, mediates the quorum sensing (QS) mechanism. This involves the production of autoinducer-2 (AI-2), which regulates important physiological traits and a variety of adaptive processes in different bacteria.