213 research outputs found
Transgenic Eimeria magna Pérard, 1925 Displays Similar Parasitological Properties to the Wild-type Strain and Induces an Exogenous Protein-Specific Immune Response in Rabbits (Oryctolagus cuniculus L.)
Rabbit coccidiosis causes great economic losses to world rabbitries. Little work has been done considering genetic manipulation on the etiological agents, rabbit Eimeria spp. In this study, we constructed a transgenic line of Eimeria magna (EmagER) expressing enhanced yellow fluorescent protein (EYFP) and red fluorescent protein (RFP) using regulatory sequences of Eimeria tenella and Toxoplasma gondii. We observed the life cycle of EmagER and confirmed that the transgenic parasites express exogenous proteins targeted to different cellular compartments throughout the entire life cycle. EYFP was expressed mainly in the nucleus and RFP both in the nucleus and cytoplasm. Then, coccidia-free, laboratory-reared 40-day-old rabbits were primarily infected with either EmagER or wild-type strain oocysts and challenged with the wild-type strain. EmagER showed similar reproductivity and immunogenicity to the wild-type strain. Finally, we examined the foreign protein-specific immune response elicited by EmagER. Rabbits were immunized with either transgenic or wild-type oocysts. Immune response against parasite-soluble antigen, EYFP and RFP in spleen, and mesenteric lymph nodes were detected by quantitative real-time PCR. The relative expression level of IFN-γ, IL-2, and TNF-α were higher in EmagER-immunized rabbits than wild-type parasites-immunized rabbits after stimulation with EYFP and RFP. Our study confirmed that a specific immune response was induced by the exogenous protein expressed by EmagER and favored future studies on application of transgenic rabbit coccidia as recombinant vaccine vectors
New genus and species of lice in the Oxylipeurus-complex (Phthiraptera, Ischnocera, Philopteridae), with an overview of the distribution of ischnoceran chewing lice on galliform hosts
Here, we describe a new genus of lice (Phthiraptera, Ischnocera) in the Oxylipeurus-complex, parasitising galliform hosts in the genera Tragopan Cuvier, 1829. This genus, Pelecolipeurus gen. nov., is separated from other members of the complex by the unique shape of the male subgenital plate and stylus, the male genitalia and other characters. The only previously-known species in the genus is Lipeurus longus Piaget, 1880, which is here tentatively re-described as Pelecolipeurus longus (Piaget, 1880), based on specimens from a non-type host, Tragopan temminckii (Gray, 1831). In addition, we describe a new species, Pelecolipeurus fujianensis sp. nov., based on specimens from Tragopan caboti (Gould, 1857). An overview of the distribution patterns of ischnoceran lice on galliforms is presented, which suggests that host phylogeny, host biogeography and host biotope, as well as elevation of host range, may all be important factors that have structured louse communities on landfowl. We transfer the genus Afrilipeurus from the Oxylipeurus-complex to the Lipeurus-complex and include an emended key to the Oxylipeurus-complex
Pathogenic Pseudorabies Virus, China, 2012
In 2012, an unprecedented large-scale outbreak of disease in pigs in China caused great economic losses to the swine industry. Isolates from pseudorabies virus epidemics in swine herds were characterized. Evidence confirmed that the pathogenic pseudorabies virus was the etiologic agent of this epidemic
Emergence of Fatal PRRSV Variants: Unparalleled Outbreaks of Atypical PRRS in China and Molecular Dissection of the Unique Hallmark
Porcine reproductive and respiratory syndrome (PRRS) is a severe viral disease in pigs, causing great economic losses worldwide each year. The causative agent of the disease, PRRS virus (PRRSV), is a member of the family Arteriviridae. Here we report our investigation of the unparalleled large-scale outbreaks of an originally unknown, but so-called “high fever” disease in China in 2006 with the essence of PRRS, which spread to more than 10 provinces (autonomous cities or regions) and affected over 2,000,000 pigs with about 400,000 fatal cases. Different from the typical PRRS, numerous adult sows were also infected by the “high fever” disease. This atypical PRRS pandemic was initially identified as a hog cholera-like disease manifesting neurological symptoms (e.g., shivering), high fever (40–42°C), erythematous blanching rash, etc. Autopsies combined with immunological analyses clearly showed that multiple organs were infected by highly pathogenic PRRSVs with severe pathological changes observed. Whole-genome analysis of the isolated viruses revealed that these PRRSV isolates are grouped into Type II and are highly homologous to HB-1, a Chinese strain of PRRSV (96.5% nucleotide identity). More importantly, we observed a unique molecular hallmark in these viral isolates, namely a discontinuous deletion of 30 amino acids in nonstructural protein 2 (NSP2). Taken together, this is the first comprehensive report documenting the 2006 epidemic of atypical PRRS outbreak in China and identifying the 30 amino-acid deletion in NSP2, a novel determining factor for virulence which may be implicated in the high pathogenicity of PRRSV, and will stimulate further study by using the infectious cDNA clone technique
A Network Simulation Platform for Hierarchical Spectrum Sharing Based Cognitive Radio Network
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