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Porcine epidemic diarrhea, a highly contagious enteric infectious disease caused by the porcine epidemic diarrhea virus (PEDV) with symptoms of vomit, diarrhea, loss of appetite of suckling pig, has led to serious economic loss to the global swine industry. In this study, a real-time fluorescence reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed to detect PEDV RNA. The real-time fluorescence RT-LAMP assay was performed at 62 t for 60 min, using a simple and portable device, the ESE-Quant Tube Scanner. The detection limit of RNA was 2.9 x 10' copies/pi, 10 times as sensitive as RT-PCR, and the detection was specific only to PEDV. Application of this method to clinical samples yielded a positivity rate of 93%, which was higher than that of RT-PCR. This technique saves time and is efficient, and is thus expected to be useful for the diagnosis of PEDV infection in the field. [ABSTRACT FROM AUTHOR]

Background: Canine parvovirus 2, a linear single-stranded DNA virus belonging to the genus Parvovirus within the family Parvoviridae, is a highly contagious pathogen of domestic dogs and several wild canidae species. Early detection of canine parvovirus (CPV-2) is crucial to initiating appropriate outbreak control strategies. Recombinase polymerase amplification (RPA), a novel isothermal gene amplification technique, has been developed for the molecular detection of diverse pathogens. In this study, a real-time RPA assay was developed for the detection of CPV-2 using primers and an exo probe targeting the CPV-2 nucleocapsid protein gene. Results: The real-time RPA assay was performed successfully at 38 ∘C, and the results were obtained within 4-12 min for 105-101 molecules of template DNA. The assay only detected CPV-2, and did not show cross-detection of other viral pathogens, demonstrating a high level of specificity. The analytical sensitivity of the real-time RPA was 101 copies/ reaction of a standard DNA template, which was 10 times more sensitive than the common RPA method. The clinical sensitivity of the real-time RPA assay matched 100% (n = 91) to the real-time PCR results. Conclusion: The real-time RPA assay is a simple, rapid, reliable and affordable method that can potentially be applied for the detection of CPV-2 in the research laboratory and point-of-care diagnosis. [ABSTRACT FROM AUTHOR]

Background: Canine distemper, caused by Canine distemper virus (CDV), is a highly contagious and fatal systemic disease in free-living and captive carnivores worldwide. Recombinase polymerase amplification (RPA), as an isothermal gene amplification technique, has been explored for the molecular detection of diverse pathogens. Methods: A real-time reverse transcription RPA (RT-RPA) assay for the detection of canine distemper virus (CDV) using primers and exo probe targeting the CDV nucleocapsid protein gene was developed. A series of other viruses were tested by the RT-RPA.Thirty-two field samples were further tested by RT-RPA, and the resuts were compared with those obtained by the real-time RT-PCR. Results: The RT-RPA assay was performed successfully at 40 °C, and the results were obtained within 3 min- 12 min. The assay could detect CDV, but did not show cross-detection of canine parvovirus-2 (CPV-2), canine coronavirus (CCoV), canine parainfluenza virus (CPIV), pseudorabies virus (PRV) or Newcastle disease virus (NDV), demonstrating high specificity. The analytical sensitivity of RT-RPA was 31.8 copies in vitro transcribed CDV RNA, which is 10 times lower than the real-time RT-PCR. The assay performance was validated by testing 32 field samples and compared to real-time RT-PCR. The results indicated an excellent correlation between RT-RPA and a reference real-time RT-PCR method. Both assays provided the same results, and R2 value of the positive results was 0.947. Conclusions: The results demonstrated that the RT-RPA assay offers an alternative tool for simple, rapid, and reliable detection of CDV both in the laboratory and point-of-care facility, especially in the resource-limited settings. [ABSTRACT FROM AUTHOR]

The situation of intercepted alien pests from imported hides in Hebei during 2013-2014 was systematically analyzed. The results showed that 163 batches of alien pests were intercepted, including 2 batches of quarantine weeds and they both were Italian cocklebur. According to the statistics of original countries, the intercepted hides from 21 countries all had alien pests, in which Australia was the largest number of batches and species of alien pests. The analysis results showed that there was severe risk in the imported hides carrying alien pests, thus to effectively prevent the invasion of alien pests to our country, several quarantine measures should be taken in the future, such as enhancing the quarantine inspection in ports, and promoting the personnel ability of interception and species identification of alien pests. [ABSTRACT FROM AUTHOR]

The encephalomyocarditis virus (EMCV) can cause acute myocarditis in young pigs or reproductive failure in sows. In this study, a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed to detect EMCV RNA. The RT-LAMP assay was highly sensitive and able to detect 2.2 x 10-5 ng of EMCV RNA, as no cross-reaction was observed with other viruses. The RT-LAMP assay was conducted in isothermal (62 °C) conditions within 50 min. The amplified products of EMCV could be detected as ladder-like bands using agarose gel electrophoresis. This is the first report to demonstrate the application of a one-step RT-LAMP assay for the detection of EMCV. The sensitive, specific and rapid RT-LAMP assay developed in this study can be applied widely in clinical diagnosis and field surveillance of EMCV. [ABSTRACT FROM AUTHOR]

[Objective] This study aimed to develop a reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for detecting BVDV. [Method] Since gp48 gene of BVDV is among the most conserved regions, a set of four primers was designed to amplify six target sequences at the gp48 gene region for the RT-LAMP assay. The optimization of the RT-LAMP reaction was performed by evaluating reaction temperature and reaction time. [Result] The RT-LAMP aasay was successfully conducted at 56 °C within 40 min under isothermal conditions, and the results could be detected as ladder-like bands using agarose gel electrophoresis. The RT-LAMP assay is highly sensitive and able to detect 3.74×10° copies/pl of BVDV RNA, as no cross-reaction was observed with other viruses. [Conclusion] Overall, the newly established RT-LAMP assay indicates the potential application in both clinical diagnosis and field surveillance of BVDV. [ABSTRACT FROM AUTHOR]

Introduction: It remains unclear whether exposure to repeated positive acceleration (+Gz) can exacerbate endothelial dysfunction on the basis of hyperlipidemia. The aim of this study was to investigate the effect of repeated +Gz exposure on endothelial function in high-fat-diet-induced hyperlipidemic rats.Material and Methods: Male Sprague-Dawley rats were randomly divided into control, repeat +Gz exposure, high-fat diet (HFD), and +Gz + HFD groups. The rats in the +Gz group were exposed to +Gz and the rats in the HFD group were fed a diet with 2% cholesterol. The rats in the +Gz + HFD group received both the +Gz exposure and HFD. Eight weeks later, the endothelium-dependent relaxation of the aorta was tested and the ultrastructure of the endothelial cells was observed using transmission electron microscopy. Quantitative real-time polymerase chain reaction and Western blot were used to detect the mRNA and protein expression of endothelial function-associated proteins.Results: Repeated +Gz exposure elevated the serum level of LDL-C in HFD rats. In the +Gz + HFD rats, the ACh-induced relaxation in the aorta rings was significantly attenuated and the endothelial cells of the aorta were dramatically damaged compared with HFD rats. Nitric oxide content and eNOS expression in the aortic tissue were markedly decreased and the oxidative stress was more serious in the +Gz + HFD rats compared with HFD rats. In addition, repeated +Gz exposure significantly increased serum ox-LDL level and LOX-1 expression in the aorta of HFD rats, thereby activating NF-κB p65 and upregulating the expression of interleukin 6, ICAM-1 and VAP-1.Conclusions: Repeated +Gz exposure promotes endothelial dysfunction in HFD-induced hyperlipidemic rats. [ABSTRACT FROM AUTHOR]