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John F. Prescott - One of the best experts on this subject based on the ideXlab platform.

  • plasmid characterization and chromosome analysis of two netf clostridium perfringens isolates associated with foal and canine necrotizing enteritis
    2016
    Co-Authors: Iman Mehdizadeh Gohari, Ashley E Whitehead, Valeria R Parreira, Patrick Boerlin, Scott Weese, Andrew M Kropinski, John F. Prescott
    Abstract:

    The recent discovery of a novel beta-pore-forming toxin, NetF, which is strongly associated with canine and foal necrotizing enteritis should improve our understanding of the role of type A Clostridium perfringens associated disease in these animals. The current study presents the complete genome sequence of two netF-positive strains, JFP55 and JFP838, which were recovered from cases of foal necrotizing enteritis and canine Hemorrhagic Gastroenteritis, respectively. Genome sequencing was done using Single Molecule, Real-Time (SMRT) technology-PacBio and Illumina Hiseq2000. The JFP55 and JFP838 genomes include a single 3.34 Mb and 3.53 Mb chromosome, respectively, and both genomes include five circular plasmids. Plasmid annotation revealed that three plasmids were shared by the two newly sequenced genomes, including a NetF/NetE toxins-encoding tcp-conjugative plasmid, a CPE/CPB2 toxins-encoding tcp-conjugative plasmid and a putative bacteriocin-encoding plasmid. The putative beta-pore-forming toxin genes, netF, netE and netG, were located in unique pathogenicity loci on tcp-conjugative plasmids. The C. perfringens JFP55 chromosome carries 2,825 protein-coding genes whereas the chromosome of JFP838 contains 3,014 protein-encoding genes. Comparison of these two chromosomes with three available reference C. perfringens chromosome sequences identified 48 (~247 kb) and 81 (~430 kb) regions unique to JFP55 and JFP838, respectively. Some of these divergent genomic regions in both chromosomes are phage- and plasmid-related segments. Sixteen of these unique chromosomal regions (~69 kb) were shared between the two isolates. Five of these shared regions formed a mosaic of plasmid-integrated segments, suggesting that these elements were acquired early in a clonal lineage of netF-positive C. perfringens strains. These results provide significant insight into the basis of canine and foal necrotizing enteritis and are the first to demonstrate that netF resides on a large and unique plasmid-encoded locus.

  • a novel pore forming toxin in type a clostridium perfringens is associated with both fatal canine Hemorrhagic Gastroenteritis and fatal foal necrotizing enterocolitis
    2015
    Co-Authors: Iman Mehdizadeh Gohari, Valeria R Parreira, Victoria J Nowell, Vivian M Nicholson, Kaitlyn Oliphant, John F. Prescott
    Abstract:

    A role for type A Clostridium perfringens in acute Hemorrhagic and necrotizing Gastroenteritis in dogs and in necrotizing enterocolitis of neonatal foals has long been suspected but incompletely characterized. The supernatants of an isolate made from a dog and from a foal that died from these diseases were both found to be highly cytotoxic for an equine ovarian (EO) cell line. Partial genome sequencing of the canine isolate revealed three novel putative toxin genes encoding proteins related to the pore-forming Leukocidin/Hemolysin Superfamily; these were designated netE, netF, and netG. netE and netF were located on one large conjugative plasmid, and netG was located with a cpe enterotoxin gene on a second large conjugative plasmid. Mutation and complementation showed that only netF was associated with the cytotoxicity. Although netE and netG were not associated with cytotoxicity, immunoblotting with specific antisera showed these proteins to be expressed in vitro. There was a highly significant association between the presence of netF with type A strains isolated from cases of canine acute Hemorrhagic Gastroenteritis and foal necrotizing enterocolitis. netE and netF were found in all cytotoxic isolates, as was cpe, but netG was less consistently present. Pulsed-field gel electrophoresis showed that netF-positive isolates belonged to a clonal population; some canine and equine netF-positive isolates were genetically indistinguishable. Equine antisera to recombinant Net proteins showed that only antiserum to rNetF had high supernatant cytotoxin neutralizing activity. The identifica-tion of this novel necrotizing toxin is an important advance in understanding the virulence of type A C. perfringens in specific enteric disease of animals.

  • clostridium perfringens type a fatal acute Hemorrhagic Gastroenteritis in a dog
    2012
    Co-Authors: Ben J Schlegel, Tony Van Dreumel, Durda Slavic, John F. Prescott
    Abstract:

    The morning after participating in a dog show, a 2-year-old Pomeranian dog was found dead in a pool of bloody feces. Necropsy revealed Hemorrhagic Gastroenteritis of the entire gastrointestinal tract, with many Gram-positive bacilli on the surface and in the lumen and crypts of the intestine. Enterotoxin-positive type A Clostridium perfringens were isolated in large numbers. This dramatic case of fatal C. perfringens Gastroenteritis highlights the need to better understand the role of this bacterium in enteric disease of dogs.

Salazar Campos, Priscilla Iveth - One of the best experts on this subject based on the ideXlab platform.

Mendoza Gaviria, Carlos Miguel - One of the best experts on this subject based on the ideXlab platform.

  • Diagnóstico de Parvovirus canino mediante el método del Rapid kit Cpv Ag en pacientes con Gastroenteritis hemorrágica en el distrito de Tarapoto
    2017
    Co-Authors: Mendoza Gaviria, Carlos Miguel
    Abstract:

    The present study was carried out in order to diagnose the prevalence of Parvovirus canine in patients with Hemorrhagic Gastroenteritis in the district of Tarapoto, province and region of San Martín in the year 2016, from a population of 4,740 dogs. To evaluate the prevalence of Parvovirus canine through the use of the CPV Ag Antigen Rapid Test Kit (Anigen Rapid Test Kit for CPV Ag), to identify the disease in relation to race, sex, age, size and neighborhood of Infected animals in Tarapoto district, as well, Proposed preventive-prophylactic measures in the presence of canine Parvovirus, it was concluded that Parvovirus canine disease in dogs with Hemorrhagic Gastroenteritis, it don’t have relation between the dependent variable outcome ( Positive or negative) by using the CPV Ag Antigen Rapid Test (Anigen Rapid Test Kit for CPV Ag). And the independent variables (sex, race, age, size, neighborhood), and the Rapit Kit has a reliability of 95%, being a useful tool in the case of having patients with Parvovirus canine symptomatology and finally proposed preventive- Prophylactic in the presence of Parvovirus canineEl presente estudio se realizó con la finalidad de diagnosticar la prevalencia de Parvovirus canino, en pacientes con Gastroenteritis hemorrágica, en distrito de Tarapoto, provincia y región San Martín el año 2016, de una población de 4740 canes, mediante una formula se tomó 60 canes, para evaluar la prevalencia de Parvovirus canino, mediante el uso de la Prueba Rápida del Antígeno para CPV Ag (Kit del Test Rápido Anigen para CPV Ag), identificar la enfermedad en relación a la raza, sexo, edad, tamaño y barrio de los animales infectados en el distrito de Tarapoto, así mismo Proponer medidas preventivas-profilácticas ante la presencia del Parvovirus canino, se llegó a la conclusión que la enfermedad Parvovirus canino, en canes con Gastroenteritis hemorrágica, no tiene una relación entre la variable dependiente resultado (positivo o negativo) mediante el uso de la Prueba Rápida del Antígeno para CPV Ag (Kit del Test Rápido Anigen para CPV Ag). y las variables independientes (sexo, raza, edad, tamaño, barrio), así mismo el Rapit Kit tiene una confiabilidad del 95 %, siendo una herramienta útil en el caso de tener pacientes con sintomatología de Parvovirus canino y finalmente se propuso medidas preventivas-profilácticas ante la presencia del Parvovirus caninoTesi

  • Diagnóstico de Parvovirus canino mediante el método del Rapid kit Cpv Ag en pacientes con Gastroenteritis hemorrágica en el distrito de Tarapoto
    2016
    Co-Authors: Mendoza Gaviria, Carlos Miguel
    Abstract:

    El presente estudio se realizó con la finalidad de diagnosticar la prevalencia de Parvovirus canino, en pacientes con Gastroenteritis hemorrágica, en distrito de Tarapoto, provincia y región San Martín el año 2016, de una población de 4740 canes, mediante una formula se tomó 60 canes, para evaluar la prevalencia de Parvovirus canino, mediante el uso de la Prueba Rápida del Antígeno para CPV Ag (Kit del Test Rápido Anigen para CPV Ag), identificar la enfermedad en relación a la raza, sexo, edad, tamaño y barrio de los animales infectados en el distrito de Tarapoto, así mismo Proponer medidas preventivas-profilácticas ante la presencia del Parvovirus canino, se llegó a la conclusión que la enfermedad Parvovirus canino, en canes con Gastroenteritis hemorrágica, no tiene una relación entre la variable dependiente resultado (positivo o negativo) mediante el uso de la Prueba Rápida del Antígeno para CPV Ag (Kit del Test Rápido Anigen para CPV Ag). y las variables independientes (sexo, raza, edad, tamaño, barrio), así mismo el Rapit Kit tiene una confiabilidad del 95 %, siendo una herramienta útil en el caso de tener pacientes con sintomatología de Parvovirus canino y finalmente se propuso medidas preventivas-profilácticas ante la presencia del Parvovirus caninoTesisThe present study was carried out in order to diagnose the prevalence of Parvovirus canine in patients with Hemorrhagic Gastroenteritis in the district of Tarapoto, province and region of San Martín in the year 2016, from a population of 4,740 dogs. To evaluate the prevalence of Parvovirus canine through the use of the CPV Ag Antigen Rapid Test Kit (Anigen Rapid Test Kit for CPV Ag), to identify the disease in relation to race, sex, age, size and neighborhood of Infected animals in Tarapoto district, as well, Proposed preventive-prophylactic measures in the presence of canine Parvovirus, it was concluded that Parvovirus canine disease in dogs with Hemorrhagic Gastroenteritis, it don’t have relation between the dependent variable outcome ( Positive or negative) by using the CPV Ag Antigen Rapid Test (Anigen Rapid Test Kit for CPV Ag). And the independent variables (sex, race, age, size, neighborhood), and the Rapit Kit has a reliability of 95%, being a useful tool in the case of having patients with Parvovirus canine symptomatology and finally proposed preventive- Prophylactic in the presence of Parvovirus canin

Pragya D. Yadav - One of the best experts on this subject based on the ideXlab platform.

  • genomic analysis reveals nairobi sheep disease virus to be highly diverse and present in both africa and in india in the form of the ganjam virus variant
    2011
    Co-Authors: Charuta Kale, Martin J. Vincent, Marina L. Khristova, Pragya D. Yadav, Akhilesh C. Mishra, Stuart T. Nichol, Devendra T. Mourya
    Abstract:

    Abstract Nairobi sheep disease (NSD) virus, the prototype tick-borne virus of the genus Nairovirus, family Bunyaviridae is associated with acute Hemorrhagic Gastroenteritis in sheep and goats in East and Central Africa. The closely related Ganjam virus found in India is associated with febrile illness in humans and disease in livestock. The complete S, M and L segment sequences of Ganjam and NSD virus and partial sequence analysis of Ganjam viral RNA genome S, M and L segments encoding regions (396 bp, 701 bp and 425 bp) of the viral nucleocapsid (N), glycoprotein precursor (GPC) and L polymerase (L) proteins, respectively, was carried out for multiple Ganjam virus isolates obtained from 1954 to 2002 and from various regions of India. M segments of NSD and Ganjam virus encode a large ORF for the glycoprotein precursor (GPC), (1627 and 1624 amino acids in length, respectively) and their L segments encode a very large L polymerase (3991 amino acids). The complete S, M and L segments of NSD and Ganjam viruses were more closely related to one another than to other characterized nairoviruses, and no evidence of reassortment was found. However, the NSD and Ganjam virus complete M segment differed by 22.90% and 14.70%, for nucleotide and amino acid respectively, and the complete L segment nucleotide and protein differing by 9.90% and 2.70%, respectively among themselves. Ganjam and NSD virus, complete S segment differed by 9.40–10.40% and 3.2–4.10 for nucleotide and proteins while among Ganjam viruses 0.0–6.20% and 0.0–1.4%, variation was found for nucleotide and amino acids. Ganjam virus isolates differed by up to 17% and 11% at the nucleotide level for the partial S and L gene fragments, respectively, with less variation observed at the deduced amino acid level (10.5 and 2%, S and L, respectively). However, the virus partial M gene fragment (which encodes the hypervariable mucin-like domain) of these viruses differed by as much as 56% at the nucleotide level. Phylogenetic analysis of partial sequence differences suggests considerable mixing and movement of Ganjam virus strains within India, with no clear relationship between genetic lineages and virus geographic origin or year of isolation. Surprisingly, NSD virus does not represent a distinct lineage, but appears as a variant with other Ganjam virus among NSD virus group.

Changchun Tu - One of the best experts on this subject based on the ideXlab platform.

  • nairobi sheep disease virus rna in ixodid ticks china 2013
    2015
    Co-Authors: Shangshu Gong, Zedong Wang, Biao He, Limin Shang, Changchun Tu
    Abstract:

    To the Editor: Nairobi sheep disease virus (NSDV; genus Nairovirus, family Bunyaviridae) causes acute Hemorrhagic Gastroenteritis in sheep and goats (1,2). First identified in Nairobi, Kenya, in 1910, it is considered endemic in East Africa (1,3). Ganjam virus, a variant of NSDV, is found in India and Sri Lanka (2). NSDV has a limited effect on animals bred in areas to which the virus is endemic but can cause large losses of animals during introduction of new livestock or transport of animals through these areas (4). In humans, NSDV infection can cause febrile illness, headache, nausea, and vomiting (5). Ticks are the main transmission vectors of NSDV and many other viral pathogens and therefore pose a major threat to public health (6,7). Here, we describe a newly discovered NSDV, named NSDV (China), identified by viral metagenomic analysis of ticks collected from the northeast region of the People’s Republic of China (Liaoning, Jilin, and Heilongjiang provinces) during May–July, 2013, and divided into 9 groups according to tick species and sampling sites. Four tick species were morphologically identified: Haemaphysalis longicornis (84.8%); Dermacentor silvarum (7.2%); D. nuttalli (5.5%); and Ixodes persulcatus (2.5%) (Technical Appendix Table 1). Of the 6,427 ticks collected, 3,410 were divided into 9 groups (average 379 ticks/group, range 163–512); each group was homogenized in SM buffer (50 mmol/L Tris, 10 mmol/L MgSO4, 0.1 mol/L NaCl, pH 7.5). Viral RNA extraction, Solexa sequencing, and analysis are described in the online Technical Appendix. Among the sequences annotated to mammalian viruses, 65 contigs were found to target the small (n = 15), medium (n = 27), and large (n = 23) segments of the NSDV genome (Technical Appendix Tables 2–4). To confirm the Solexa results, a 376-nt fragment of the NSDV small gene segment was amplified by reverse transcription PCR (RT-PCR) by using primers P1 (5′-AGCAAAGAGCACATTGACTGGGC-3′) and P2 (5′-CTGTCACACCTGCCTTCCAA-3′). Ticks in 3 H. longicornis groups were positive for NSDV: group 1 from sheep in Jian, Jilin Province (125°34′E, 40°52′N); group 2 from cattle in Jinxing, Jilin Province (130°38′E, 42°25′N); and group 5 from sheep in Dandong, Liaoning Province (124°23′E, 40°07′N). Ticks in the other groups were negative. The obtained sequences shared 92% identity with NSDV from H. intermedia in India. The full-length sequence of NSDV was then obtained from group 2 by RT-PCR by using primers based on the Solexa sequences or the conserved sequences of nairoviruses (Technical Appendix Table 5). The complete sequences of the small, medium, and large segments of NSDV (China) (GenBank accession nos. {"type":"entrez-nucleotide-range","attrs":{"text":"KM464724-KM464726","start_term":"KM464724","end_term":"KM464726","start_term_id":"728892682","end_term_id":"728892686"}}KM464724-KM464726) contained 1,590, 5,077, and 12,081 nt, respectively; that is, they were similar to other NSDVs. Sequence comparisons showed 75.1%–89.6% identity with other NSDVs at the nucleotide level and 81.3%–96.7% at the deduced amino acid level (Technical Appendix Table 6). Compared with other member species within the genus Nairovirus (Dugbe, Kupe, Hazara, and Crimean Congo Hemorrhagic fever viruses), low identities (37.5%–68.6%) were observed at both nucleotide and amino acid levels (Technical Appendix Table 6). Phylogenetic analysis based on the amino acid sequences grouped the virus together with NSDVs from Africa and South Asia (Figure). Figure Phylogenetic analysis of Nairobi sheep disease virus (China) and other nairoviruses. The phylogenetic trees were generated in MEGA5.2 software (http://www.megasoftware.net). The complete coding regions for nucleocapsid protein in the small segment (A), ... The remaining tick samples of the NSDV-positive groups were used to determine the infection frequency by using RT-PCR to analyze primers P1 and P2. We assayed 104 tick pools (average 15 ticks/pool, range 8–40), 13 pools of 416 ticks in Jian Province and 91 pools of 1,095 ticks in Jinxing Province; 12.5% (13/104) tested positive, 38.5% (5/13) in Jian and 8.8% (8/91) in Jinxing. The higher prevalence in Jian Province may result from more ticks in the pools. Attempts to isolate virus from the positive samples in cell lines (Vero and BHK-21) and suckling mice were unsuccessful; thus, its pathogenicity could not be determined. In Africa, NSDV is primarily transmitted by R. appendiculatus ticks (5). In South Asia (India and Sri Lanka), NSDV has been isolated from ticks (H. intermedia, H. wellingtoni, and R. haemaphysaloides), mosquitoes, sheep and humans; H. intermedia ticks are considered the main vector for the virus (5,8,9). NSDV had not previously been reported from East Asia. The isolate we identified, NSDV (China), is genetically divergent from the NSDVs of South Asia and Africa and is therefore a novel strain, with H. longicornis likely the main vector. Nairobi sheep disease has not been reported in China and East Asia, but our results indicate the risk of its occurrence in these regions, where H. longicornis is widely distributed (10). More extensive investigation to clarifty the natural circulation of NSDV among ticks should be conducted and surveillance of sheep improved to prevent outbreaks of Nairobi sheep disease in China and East Asia. Technical Appendix: Tick collection, RNA extraction and processing, sequencing, and analysis of data resulting in identification of Nairobi sheep disease virus RNA in ixodid ticks, China, 2013. Click here to view.(107K, pdf)