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Joaquim Segales - One of the best experts on this subject based on the ideXlab platform.
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a proposal on porcine circovirus type 2 pcv2 genotype definition and their relation with postweaning multisystemic Wasting Syndrome pmws occurrence
Veterinary Microbiology, 2008Co-Authors: Llorenc Grauroma, Elisa Crisci, Marina Sibila, Sergio Lopezsoria, M Nofrarias, Marti Cortey, Lorenzo Fraile, Alex Olvera, Joaquim SegalesAbstract:Porcine circovirus type 2 (PCV2) is the essential infectious agent of postweaning multisystemic Wasting Syndrome (PMWS). Despite first sequencing studies did not find any association between PCV2 sequences and PMWS occurrence, recent works have suggested the opposite. In the present study, 87 open reading frame 2 (ORF2) sequences obtained from pigs with different clinical conditions and coming from farms with different PMWS status were analyzed. Results further confirmed the existence of two genogroups and the definition of two PCV2 genotypes (1 and 2) is proposed. All sequences included in genotype 1 came from pigs from PMWS affected farms, while all sequences obtained from non-PMWS affected farms corresponded to genotype 2. Moreover, infection of single pigs from PMWS affected farms harbouring both genotypes is described. Present results suggest that PCV2 genotype 1 may potentially be more pathogenic than PCV2 genotype 2.
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prevalence of swine torque teno virus in post weaning multisystemic Wasting Syndrome pmws affected and non pmws affected pigs in spain
Journal of General Virology, 2006Co-Authors: Tuija Kekarainen, Marina Sibila, Joaquim SegalesAbstract:The present study was designed to investigate the prevalence of swine Torque teno virus (TTV) in post-weaning multisystemic Wasting Syndrome (PMWS)-affected and non-affected Spanish swine. Nested PCR (nPCR) assays to detect two distinct TTV genogroups were applied. A significantly higher prevalence of TTV infection was found in sera from PMWS-affected animals (97 %) than in sera from non-PMWS-affected animals (78 %). Whilst PMWS-affected pigs (91 %) were more likely to be infected with TTV from genogroup 2 than non-PMWS-affected swine (72 %), no such difference was observed with genogroup 1. Nucleotide sequences of nPCR products were 91–99 % identical between strains within a genogroup. In contrast, inter-genogroup sequence identities were 49–58 %. Phylogenetic analyses demonstrated that genogroups form different clusters without association with PMWS or porcine circovirus type 2 infection status of the animals. These results indicate a high prevalence of both swine TTV genogroups in Spain, being present more frequently in PMWS-affected animals than in non-PMWS-affected animals.
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comparison of porcine circovirus type 2 load in serum quantified by a real time pcr in postweaning multisystemic Wasting Syndrome and porcine dermatitis and nephropathy Syndrome naturally affected pigs
Journal of Virological Methods, 2004Co-Authors: Alex Olvera, Maria Calsamiglia, Joaquim Segales, Marina Sibila, M DomingoAbstract:Postweaning multisystemic Wasting Syndrome (PMWS) diagnosis is based on the presence of characteristic histopathological lymphoid lesions and porcine circovirus type 2 (PCV2) within these lesions. Previous studies indicate that PCV2 load is higher in PMWS affected than in PCV2 infected, healthy pigs. On the other hand, PCV2 has been suggested to play a role in porcine dermatitis and nephropathy Syndrome (PDNS) pathogenesis. This study describes a new TaqMan real time PCR assay and its use to quantify viral load in serum samples. Serum viral loads were related with different degrees of PMWS characteristic lesions and PDNS cases. DNA extracted from serum samples from 75 animals with mild, moderate and severe PMWS lesions and 12 animals with PDNS was used as template. PCV2 DNA was quantified in 69 of 75 PMWS cases and in 11 of 12 PDNS cases. Significant differences in PCV2 load were observed between animals with severe, moderate and mild PMWS lesions, although variability within each group was high, probably due to heterogeneity in disease progression. These results suggest that high viral load is a major feature of PMWS affected pigs. PDNS affected animals had lower PCV2 loads. No significant differences in viral load were found between animals suffering from PDNS and animals with mild PMWS characteristic lesions, which were unaffected clinically.
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cytokine profiles of peripheral blood mononuclear cells from pigs with postweaning multisystemic Wasting Syndrome in response to mitogen superantigen or recall viral antigens
Journal of General Virology, 2003Co-Authors: Laila Darwich, M Balasch, Joan Planaduran, Joaquim Segales, Mariano Domingo, Enric MateuAbstract:In vitro cytokine profiles of peripheral blood mononuclear cells (PBMC) from pigs with postweaning multisystemic Wasting Syndrome (PMWS) and healthy pigs were determined in response to recall viral antigens (porcine circovirus type 2; PCV2), mitogens (phytohaemagglutinin) or superantigens (staphylococcal enterotoxin B). PBMC from PMWS-affected pigs, in contrast to those from healthy pigs, responded to recall PCV2 antigen by releasing IL-10 and IFN-γ, but they were less able or even unable to produce IL-4, IL-2 or IFN-γ upon challenge with mitogen or superantigen. Moreover, only PCV2 had the ability to downregulate or suppress the release of IL-4 and IL-2 from PBMC from both healthy and diseased animals, and to stimulate the production of pro-inflammatory cytokines (IL-1β, IL-8). In conclusion, the immune system cells of PMWS pigs have a diminished ability to perform their immunological functions upon viral or immunostimulatory molecules. In addition, PCV2 can alter the functionality of PBMC in both healthy and PMWS pigs.
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detection of porcine circovirus types 1 and 2 in serum and tissue samples of pigs with and without postweaning multisystemic Wasting Syndrome
Journal of Clinical Microbiology, 2002Co-Authors: Maria Calsamiglia, Joaquim Segales, C. Rosell, Mariano Domingo, Josefina QuintanaAbstract:Presence of porcine circovirus type 1 (PCV1) and PCV2 was studied in sera and superficial inguinal lymph nodes from postweaning multisystemic Wasting Syndrome (PMWS)-affected and non-PMWS-affected pigs by using in situ hybridization and PCR. PCV1 and PCV2 were found in less than 3% and more than 50% of the samples, respectively. The most sensitive technique and site was PCR in superficial inguinal lymph nodes, but in situ hybridization correlated better with presence of characteristic lesions.
Gordon Allan - One of the best experts on this subject based on the ideXlab platform.
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reproduction of post weaning multi systemic Wasting Syndrome in an animal disease model as a tool for vaccine testing under controlled conditions
Research in Veterinary Science, 2016Co-Authors: John Mckillen, I Mcnair, Paula Lagan, Karen Mckay, Julie Mcclintock, Veronica Casement, Catherine Elisabeth Charreyre, Gordon AllanAbstract:Snatch farrowed, colostrum deprived piglets were inoculated with different combinations of porcine circovirus 2, porcine parvovirus and Erysipelothrix rhusiopathiae candidate vaccines. 10 piglets were mock-vaccinated. Following virus challenge with a combined porcine circovirus 2/porcine parvovirus inoculum, all animals were monitored and samples taken for serology, immunohistochemistry and qPCR. At 24 dpc all non-vaccinated animals remaining were exhibiting signs of post-weaning multi-systemic Wasting Syndrome which was confirmed by laboratory analysis. Details of the study, analysis of samples and performance of the candidate vaccines are described.
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detection of a novel porcine boca like virus in the background of porcine circovirus type 2 induced postweaning multisystemic Wasting Syndrome
Virus Research, 2009Co-Authors: Annelie Blomstrom, Gordon Allan, John Mckillen, Per Wallgren, Sandor Belak, Caroline Fossum, Mikael BergAbstract:Porcine circovirus type 2 (PCV-2) has been found to be the causative agent of postweaning multisystemic Wasting Syndrome (PMWS). However, PCV-2 is a ubiquitous virus in the swine population and a majority of pigs infected with PCV-2 do not develop the disease. Different factors such as age, maintenance, the genetics of PCV-2, other pathogens, etc. have been suggested to contribute to the development of PMWS. However, so far no proven connection between any of these factors and the disease development has been found. In this study we explored the possible presence of other so far unknown DNA containing infectious agents in lymph nodes collected from Swedish pigs with confirmed PMWS through random amplification and high-throughput sequencing. Although the vast majority of the amplified genetic sequences belonged to PCV-2, we also found genome sequences of Torque Teno virus (TTV) and of a novel parvovirus. The detection of TTV was expected since like PCV-2, TTV has been found to have high prevalence in pigs around the world. We were able to amplify a longer region of the parvovirus genome, consisting of the entire NP1 and partial VP1/2. By comparative analysis of the nucleotide sequences and phylogenetic studies we propose that this is a novel porcine parvovirus, with genetic relationship to bocaviruses.
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effect of coinfection with genogroup 1 porcine torque teno virus on porcine circovirus type 2 associated postweaning multisystemic Wasting Syndrome in gnotobiotic pigs
American Journal of Veterinary Research, 2008Co-Authors: Gordon Allan, S. KrakowkaAbstract:Objective—To determine whether genogroup 1 porcine torque teno virus (g1-TTV) can potentiate clinical disease associated with porcine circovirus type 2 (PCV2). Sample population—33 gnotobiotic baby pigs. Procedures—Pigs were allocated into 7 groups: group A, 5 uninoculated control pigs from 3 litters; group B, 4 pigs oronasally inoculated with PCV2 alone; group C, 4 pigs inoculated IP with first-passage g1-TTV alone; group D, 4 pigs inoculated IP with fourth-passage g1-TTV alone; group E, 6 pigs inoculated IP with first-passage g1-TTV and then oronasally inoculated with PCV2 7 days later; group F, 6 pigs inoculated IP with fourth-passage g1-TTV and then inoculated oronasally with PCV2 7 days later; and group G, 4 pigs inoculated oro-nasally with PCV2 and then inoculated IP with fourth-passage g1-TTV 7 days later. Results—6 of 12 pigs inoculated with g1-TTV prior to PCV2 developed acute onset of postweaning multisystemic Wasting Syndrome (PMWS). None of the pigs inoculated with g1-TTV alone or PCV2 alone o...
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phylogenetic analysis of porcine circovirus type 2 pcv2 pre and post epizootic postweaning multisystemic Wasting Syndrome pmws
Virus Genes, 2008Co-Authors: Sirje Timmusk, Gordon Allan, Per Wallgren, Inger Marit Brunborg, Frida Hasslung Wikstrom, Brian Meehan, Michael Mcmenamy, Francis McneillyAbstract:The porcine circovirus type 2 (PCV2) genome encodes three major open reading frames (ORFs) encoding the replicase proteins (ORF1), the viral capsid protein (ORF2), and a protein with suggested apoptotic activity (ORF3). Previous phylogenetic analyses of complete genome sequences of PCV2 from GenBank have demonstrated 95–100% intra-group nucleotide sequence identity. However, although these isolates were readily grouped into clusters and clades, there was no correlation between the occurrence of specific PCV2 genotypes and the geographic origin or health status of the pig. In the present study, a unique dataset from a field study spanning the years pre and post the recognition of postweaning multisystemic Wasting Syndrome (PMWS) in Sweden was utilized. Using this dataset it was possible to discriminate three Swedish genogroups (SG1-3) of PCV2, of which SG1 was recovered from a pig on a healthy farm ten years before the first diagnosis of PMWS in Sweden. The SG1 PCV2/ORF2 gene sequence has been demonstrated to exhibit a high genetic stability over time and has subsequently only been demonstrated in samples from pigs on nondiseased farms. In contrast, SG2 was almost exclusively found on farms that had only recently broken down with PMWS whereas the SG3 genogroup predominated in pigs from PMWS-affected farms. These results further support the results obtained from earlier in vitro and in vivo experimental models and suggest the association of specific PCV2 genogroups with diseased and nondiseased pigs in the field.
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association of lymphopenia with porcine circovirus type 2 induced postweaning multisystemic Wasting Syndrome pmws
Veterinary Immunology and Immunopathology, 2003Co-Authors: Jens Nielsen, Isabelle Vincent, Anette Botner, A S Ladekjaermikkelsen, Gordon Allan, Artur Summerfield, Kenneth C McculloughAbstract:Abstract The composition of peripheral blood leukocyte populations was studied following experimental PCV2-infection in 3-week-old piglets. Four of 10 PCV2-infected piglets developed clinical and pathological symptoms consistent with postweaning multisystemic Wasting Syndrome (PMWS) between 14 and 21 days post-inoculation (p.i.), and were characterised as PMWS-affected. Only these four PMWS-affected piglets, but neither the non-symptomatic infected nor control animals, developed a clear leukopenia. Kinetic analysis demonstrated a clear loss of both CD21+ B and CD3+ T lymphocytes in the PMWS-affected piglets. By CD3/CD4/CD8 triple labelling, the influence of PCV2 infection on all T cell sub-populations was discernible. A loss of CD3+CD4+CD8+ memory/activated Th lymphocytes was particularly notable. However, all T lymphocyte sub-populations—CD3+CD4+CD8+ memory Th, CD3+CD4+CD8− naive Th, CD3+CD4−CD8+ Tc and CD3+CD4−CD8− γδ TCR+ lymphocytes—were susceptible to PCV2 infection-induced lymphopenia. CD3−CD4−CD8+ NK cells were also depleted in the PMWS-affected animals, but granulocytes and monocytes were less affected. In conclusion, PCV2 infection induces primarily a lymphopenia, but only in animals which subsequently develop PMWS. The lymphopenia can be identified early p.i., particularly with the B lymphocytes. Memory/activated Th lymphocytes might be affected more than the other T cell sub-populations, but as time progressed a collapse of both T and B cell populations was clear.
Mikael Berg - One of the best experts on this subject based on the ideXlab platform.
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studies of porcine circovirus type 2 porcine boca like virus and torque teno virus indicate the presence of multiple viral infections in postweaning multisystemic Wasting Syndrome pigs
Virus Research, 2010Co-Authors: Annelie Blomstrom, Per Wallgren, Sandor Belak, Caroline Fossum, Lisbeth Fuxler, Mikael BergAbstract:In a previous study, using random amplification and large-scale sequencing technology, we identified a novel porcine parvovirus belonging to the genus Bocavirus in the background of porcine circovirus type 2 (PCV-2) in Swedish pigs with postweaning multisystemic Wasting Syndrome (PMWS). In addition to bocavirus we demonstrated the presence of torque teno virus (TTV) genogroups 1 and 2 in these cases of PMWS, indicating the simultaneous presence of several viruses in this disease complex. In the present study, 34 PMWS-affected animals and 24 pigs without PMWS were screened by PCR for the presence of PCV-2, TTV-1, TTV-2 and porcine boca-like virus (Pbo-likeV). The studies revealed the following infection rates in the PMWS-affected pigs: PCV-2 100%, TTV-1 77%, TTV-2 94% and Pbo-likeV 88%. In comparison, the pigs without PMWS had the following rates: PCV-2 80%, TTV-1 79%, TTV-2 83% and Pbo-likeV 46%. The sequence identity between the different Swedish Pbo-likeV sequences ranged between 98% and 100%. By checking co-infection, it was found that 71% of the PMWS-affected pigs harbor simultaneously all these viruses. As a contrast, in the group without PMWS only 33% of the animals were positive simultaneously for these viruses. These observations indicate a multiple viral infection in PMWS-affected pigs. It has to be studied further if the clinical manifestation of PMWS might be due to synergistic effects of different viruses acting together.
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detection of a novel porcine boca like virus in the background of porcine circovirus type 2 induced postweaning multisystemic Wasting Syndrome
Virus Research, 2009Co-Authors: Annelie Blomstrom, Gordon Allan, John Mckillen, Per Wallgren, Sandor Belak, Caroline Fossum, Mikael BergAbstract:Porcine circovirus type 2 (PCV-2) has been found to be the causative agent of postweaning multisystemic Wasting Syndrome (PMWS). However, PCV-2 is a ubiquitous virus in the swine population and a majority of pigs infected with PCV-2 do not develop the disease. Different factors such as age, maintenance, the genetics of PCV-2, other pathogens, etc. have been suggested to contribute to the development of PMWS. However, so far no proven connection between any of these factors and the disease development has been found. In this study we explored the possible presence of other so far unknown DNA containing infectious agents in lymph nodes collected from Swedish pigs with confirmed PMWS through random amplification and high-throughput sequencing. Although the vast majority of the amplified genetic sequences belonged to PCV-2, we also found genome sequences of Torque Teno virus (TTV) and of a novel parvovirus. The detection of TTV was expected since like PCV-2, TTV has been found to have high prevalence in pigs around the world. We were able to amplify a longer region of the parvovirus genome, consisting of the entire NP1 and partial VP1/2. By comparative analysis of the nucleotide sequences and phylogenetic studies we propose that this is a novel porcine parvovirus, with genetic relationship to bocaviruses.
Andre Jestin - One of the best experts on this subject based on the ideXlab platform.
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molecular characterization of porcine circovirus type 2 isolates from post weaning multisystemic Wasting Syndrome affected and non affected pigs
Journal of General Virology, 2004Co-Authors: Claire De Boisseson, Eric Eveno, Veronique Beven, Laurent Bigarre, Richard Thiery, Nicolas Rose, Francois Madec, Andre JestinAbstract:Porcine circovirus type 2 (PCV2) is recognized as a primary cause in post-weaning multisystemic Wasting Syndrome (PMWS). In this study, both PCV1 and PCV2 types were studied in pigs originating from PMWS-affected (+) and non-affected (−) herds from Brittany. PCV2 was identified by PCR in 100 % of animals from PMWS(+) herds and in 76 % from PMWS(−) herds, while PCV1 was not detected. The complete sequences of 38 PCV2 isolates were determined and 23 new variants were identified, displaying between 94·6 and 99·9 % nucleotide identity with one another. Although highly related to all the PCV2 sequences available in databases, the isolates from France gathered in a distinct subcluster. Compared with the 13 PCV2 from PMWS(+) farms, the 10 PMWS(−) sequences exhibited a slightly higher variability. No viral molecular marker specific to a pathogenic state could be identified, even by including other PCV2 variants isolated from PMWS-suffering animals from other countries. We concluded that the PMWS outbreaks in Brittany are most likely not due to the emergence of a new genotype of circovirus.
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protection of swine against post weaning multisystemic Wasting Syndrome pmws by porcine circovirus type 2 pcv2 proteins
Vaccine, 2003Co-Authors: Philippe Blanchard, D Mahe, Roland Cariolet, A Keranflech, M A Baudouard, P Cordioli, E Albina, Andre JestinAbstract:Porcine circovirus type 2 (PCV2) is known to be associated with post-weaning multisystemic Wasting Syndrome (PMWS), a recently described disease of young pigs. Since no PCV2 vaccine was available so far, we have developed a specific PCV2 vaccine candidate. The Orf1-encoded replication protein and Orf2-encoded capsid protein of PCV2 were expressed and detected in either mammalian or insect expression systems. In a first trial, Orf2 protein was found to be a major immunogen, inducing protection in a prime-boost protocol; the piglets received a first injection with plasmids directing Orf2 protein and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression, followed by a second injection, a fortnight later, associated with baculovirus-expressed Orf2 protein. As evaluated by growth parameters, clinical signs (fever), seroconversion, the pigs were protected against a PCV2 challenge after vaccination. In a second trial, protection induced by a subunit vaccine was even better than the one induced by DNA vaccine, since PCV2 replication was completely inhibited.
Liangfu Zhou - One of the best experts on this subject based on the ideXlab platform.
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Diagnosis and Management of Combined Central Diabetes Insipidus and Cerebral Salt Wasting Syndrome After Traumatic Brain Injury.
World neurosurgery, 2015Co-Authors: Xiaolan Zhou, Liang Gao, Ying Mao, Li Fei, Liangfu ZhouAbstract:Background Combined central diabetes insipidus and cerebral salt Wasting Syndrome after traumatic brain injury (TBI) is rare, is characterized by massive polyuria leading to severe water and electrolyte disturbances, and usually is associated with very high mortality mainly as a result of delayed diagnosis and improper management. Methods We retrospectively reviewed the clinical presentation, management, and outcomes of 11 patients who developed combined central diabetes insipidus and cerebral salt Wasting Syndrome after traumatic brain injury to define distinctive features for timely diagnosis and proper management. Results The most typical clinical presentation was massive polyuria (10,000 mL/24 hours or >1000 mL/hour) refractory to vasopressin alone but responsive to vasopressin plus cortisone acetate. Other characteristic presentations included low central venous pressure, high brain natriuretic peptide precursor level without cardiac dysfunction, high 24-hour urine sodium excretion and hypovolemia, and much higher urine than serum osmolarity; normal serum sodium level and urine specific gravity can also be present. Timely and adequate infusion of sodium chloride was key in treatment. Of 11 patients, 5 had a good prognosis 3 months later (Extended Glasgow Outcome Scale score ≥6), 1 had an Extended Glasgow Outcome Scale score of 4, 2 died in the hospital of brain hernia, and 3 developed a vegetative state. Conclusions For combined diabetes insipidus and cerebral salt Wasting Syndrome after traumatic brain injury, massive polyuria is a major typical presentation, and intensive monitoring of fluid and sodium status is key for timely diagnosis. To achieve a favorable outcome, proper sodium chloride supplementation and cortisone acetate and vasopressin coadministration are key.
