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Pavio N.,Laboratory for Animal Health | Pavio N.,French National Institute for Agricultural Research | Pavio N.,National Veterinary School of Alfort | Meng X.-J.,Center for Molecular Medicine and Infectious Diseases | And 3 more authors.
Current Opinion in Virology | Year: 2015

The concept of zoonotic viral hepatitis E has emerged a few years ago following the discovery of animal strains of hepatitis E virus (HEV), closely related to human HEV, in countries where sporadic cases of hepatitis E were autochthonous. Recent advances in the identification of animal reservoirs of HEV have confirmed that strains circulating in domestic and wild pigs are genetically related to strains identified in indigenous human cases. The demonstration of HEV contamination in the food chain or pork products has indicated that HEV is frequently a foodborne zoonotic pathogen. Direct contacts with infected animals, consumption of contaminated animal meat or meat products are all potential means of zoonotic HEV transmission. The recent identification of numerous other genetically diverse HEV strains from various animal species poses additional potential concerns for HEV zoonotic infection. © 2014 Published by Elsevier B.V. Source

Maciel B.M.,University Estadual Of Santa Cruz | Dias J.C.T.,University Estadual Of Santa Cruz | Romano C.C.,University Estadual Of Santa Cruz | Sriranganathan N.,Center for Molecular Medicine and Infectious Diseases | And 2 more authors.
Genetics and Molecular Research | Year: 2011

Quantification of Salmonella in asymptomatic carrier animals can be used to assess microbial risk and monitor the level of contamination in domestic animals used for food production. We examined the sensitivity, specificity and accuracy of real-time qPCR, without pre-enrichment or selective enrichment stages, for the quantification of S. enterica serovar Enteritidis in resistant mice, as a model of asymptomatic carrier animal. The results were compared with those obtained by traditional bacteriological culture methods, the gold standard test. Two hundred and forty-three samples, including spleen, liver, mesenteric lymph nodes, portions of intestine, intestinal content of the ileocecal portion, and feces, were collected from a group of 27 C57BL/6 mice, that had been intragastrically inoculated with high doses of S. enterica serovar Enteritidis. The real-time qPCR assay presented a consistent linearity of the standard curve (r2 = 0.999), with very low differences between melting temperatures, and low coefficients of variation in intra- (<1%) and interassay (<2%) comparisons. The primers were highly specific; there was no amplification with other Salmonella serovars or with DNA from uninfected tissues and feces from mice. The detection limit of the technique was defined as 32 copies of S. enterica serovar Enteritidis. A sensitivity of 90%, a specificity of 77% and an accuracy of 79% were obtained. The higher sensitivity of PCR was reflected in a kappa coefficient of 0.41, showing moderate agreement between tests. We conclude that real-time qPCR is a good alternative for diagnostic scanning in asymptomatic carrier animals, due to its high sensitivity and rapidity. © FUNPEC-RP. Source

Meng X.J.,Center for Molecular Medicine and Infectious Diseases
Veterinary Microbiology | Year: 2010

Hepatitis E virus (HEV) is a small, non-enveloped, single-strand, positive-sense RNA virus of approximately 7.2 kb in size. HEV is classified in the family Hepeviridae consisting of four recognized major genotypes that infect humans and other animals. Genotypes 1 and 2 HEV are restricted to humans and often associated with large outbreaks and epidemics in developing countries with poor sanitation conditions, whereas genotypes 3 and 4 HEV infect humans, pigs and other animal species and are responsible for sporadic cases of hepatitis E in both developing and industrialized countries. The avian HEV associated with Hepatitis-Splenomegaly syndrome in chickens is genetically and antigenically related to mammalian HEV, and likely represents a new genus in the family. There exist three open reading frames in HEV genome: ORF1 encodes non-structural proteins, ORF2 encodes the capsid protein, and the ORF3 encodes a small phosphoprotein. ORF2 and ORF3 are translated from a single bicistronic mRNA, and overlap each other but neither overlaps ORF1. Due to the lack of an efficient cell culture system and a practical animal model for HEV, the mechanisms of HEV replication and pathogenesis are poorly understood. The recent identification and characterization of animal strains of HEV from pigs and chickens and the demonstrated ability of cross-species infection by these animal strains raise potential public health concerns for zoonotic HEV transmission. It has been shown that the genotypes 3 and 4 HEV strains from pigs can infect humans, and vice versa. Accumulating evidence indicated that hepatitis E is a zoonotic disease, and swine and perhaps other animal species are reservoirs for HEV. A vaccine against HEV is not yet available. © 2009 Elsevier B.V. All rights reserved. Source

Roop II R.M.,East Carolina University | Caswell C.C.,Center for Molecular Medicine and Infectious Diseases
Cell Host and Microbe | Year: 2013

Studies described by Eisele et al. (2013) and Xavier et al. (2013) in this issue of Cell Host & Microbe show that the bacterial pathogens Salmonella and Brucella exploit the increased levels of glucose present in alternatively activated macrophages to sustain chronic infections in experimentally infected mice. © 2013 Elsevier Inc. Source

Caudell D.,Center for Molecular Medicine and Infectious Diseases | Caudell D.,U.S. National Institutes of Health | Harper D.P.,U.S. National Institutes of Health | Harper D.P.,Uniformed Services University of the Health Sciences | And 5 more authors.
Blood | Year: 2010

The t(10;11) translocation results in a CALM-AF10 fusion gene in a subset of leukemia patients. Expression of a CALM-AF10 transgene results in leukemia, with prolonged latency and incomplete penetrance, suggesting that additional events are necessary for leukemic transformation. CALM-AF10 mice infected with the MOL4070LTR retrovirus developed acute leukemia, and ligation-mediated polymerase chain reaction was used to identify retroviral insertions at 19 common insertion sites, including Zeb2, Nf1, Mn1, Evi1, Ift57, Mpl, Plag1, Kras, Erg, Vav1, and Gata1. A total of 26% (11 of 42) of the mice had retroviral integrations near Zeb2, a transcriptional corepressor leading to overexpression of the Zeb2-transcript. A total of 91% (10 of 11) of mice with Zeb2 insertions developed B-lineage acute lymphoblastic leukemia, suggesting that Zeb2 activation promotes the transformation of CALM-AF10 hematopoietic precursors toward B-lineage leukemias. More than half of the mice with Zeb2 integrations also had Nf1 integrations, suggesting cooperativity among CALM-AF10, Zeb2, and Ras pathway mutations. We searched for Nras, Kras, and Ptpn11 point mutations in the CALM-AF10 leukemic mice. Three mutations were identified, all of which occurred in mice with Zeb2 integrations, consistent with the hypothesis that Zeb2 and Ras pathway activation promotes B-lineage leukemic transformation in concert with CALM-AF10. Source

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