Resultado da pesquisa (15)

Termo utilizado na pesquisa phylogenetic analysis

#11 - Genetic diversity of bovine viral diarrhoea virus (BVDV) from Peru and Chile, p.41-44

Abstract in English:

ABSTRACT.- Ståhl K., Benito A., Felmer R., Zuñiga J., Reinhardt G., Rivera H., Baule C. & Moreno-López J. 2009. Genetic diversity of bovine viral diarrhoea virus (BVDV) from Peru and Chile. Pesquisa Veterinária Brasileira 29(1):41-44. Joint Virology Research and Development Division, National Veterinary Institute and Swedish University of Agricultural Sciences Uppsala, Sweden. E-mail: Karl.Stahl@bvf.slu.se Twenty-five BVDV strains, detected in serum from persistently infected cattle from Peru (n=15) and Chile (n=10) were genetically characterized. The phylogenetic analysis based on the 5’ UTR showed that all 25 strains belonged to genotype 1. Twenty-three of the strains could further be subdivided into subtype 1b, and two out of ten Chilean strains into subtype 1a. In conclusion, in total 23 out of 25 strains analyzed were of genotype 1, subtype 1b. This is the predominant BVDV subtype in many countries all over the world, including USA. The close homology with previously described strains reflects the influence of livestock trade on the diversity of BVDV circulating within and between countries and continents. Peru and Chile have imported large numbers of cattle from USA and Europe, mostly with insufficient or lacking health documentation.

Abstract in Portuguese:

ABSTRACT.- Ståhl K., Benito A., Felmer R., Zuñiga J., Reinhardt G., Rivera H., Baule C. & Moreno-López J. 2009. Genetic diversity of bovine viral diarrhoea virus (BVDV) from Peru and Chile. Pesquisa Veterinária Brasileira 29(1):41-44. Joint Virology Research and Development Division, National Veterinary Institute and Swedish University of Agricultural Sciences Uppsala, Sweden. E-mail: Karl.Stahl@bvf.slu.se Twenty-five BVDV strains, detected in serum from persistently infected cattle from Peru (n=15) and Chile (n=10) were genetically characterized. The phylogenetic analysis based on the 5’ UTR showed that all 25 strains belonged to genotype 1. Twenty-three of the strains could further be subdivided into subtype 1b, and two out of ten Chilean strains into subtype 1a. In conclusion, in total 23 out of 25 strains analyzed were of genotype 1, subtype 1b. This is the predominant BVDV subtype in many countries all over the world, including USA. The close homology with previously described strains reflects the influence of livestock trade on the diversity of BVDV circulating within and between countries and continents. Peru and Chile have imported large numbers of cattle from USA and Europe, mostly with insufficient or lacking health documentation.


#12 - Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC), p.533-540

Abstract in English:

ABSTRACT.- Campos T.A., Lago J.C., Nakazato G., Stehling E.G., Brocchi M., Castro A.F.P. & Silveira W.D. 2008. Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC). Pesquisa Veterinária Brasileira 28(10):533-540. Departamento de Microbiologia e Immunologia, Instituto de Biologia, Unicamp, Cidade Universitrária Zeferino Vaz s/n, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br The presence of iron uptake (irp-2, fyuA, sitA, fepC, iucA), adhesion (iha, lpfAO157/O141, lpfAO157/O154, efa, toxB) and invasion (inv, ial-related DNA sequences and assignment to the four main Escherichia coli phylogenetic groups (A, B1, B2 e D) were determined in 30 commensal E. coli strains isolated from healthy chickens and in 49 APEC strains isolated from chickens presenting clinical signs of septicemia (n=24) swollen head syndrome (n=14) and omphalitis (n=11) by PCR. None of the strains presented DNA sequences related to the inv, ial, efa, and toxB genes. DNA sequences related to lpfAO157/O154, iucA, fepC, and irp-2 genes were significantly found among pathogenic strains, where iucA gene was associated with septicemia and swollen head syndrome and fepC and irp-2 genes were associated with swollen head syndrome strains. Phylogenetic typing showed that commensal and omphalitis strains belonged mainly to phylogenetic Group A and swollen head syndrome to phylogenetic Group D. Septicemic strains were assigned in phylogenetic Groups A and D. These data could suggest that clonal lineage of septicemic APEC strains have a multiple ancestor origin; one from a pathogenic bacteria ancestor and other from a non-pathogenic ancestor that evolved by the acquisition of virulence related sequences through horizontal gene transfer. Swollen head syndrome may constitute a pathogenic clonal group. By the other side, omphalitis strains probably constitute a non-pathogenic clonal group, and could cause omphalitis as an opportunistic infection. The sharing of virulence related sequences by human pathogenic E. coli and APEC strains could indicate that APEC strains could be a source of virulence genes to human strains and could represent a zoonotic risk.

Abstract in Portuguese:

ABSTRACT.- Campos T.A., Lago J.C., Nakazato G., Stehling E.G., Brocchi M., Castro A.F.P. & Silveira W.D. 2008. Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC). Pesquisa Veterinária Brasileira 28(10):533-540. Departamento de Microbiologia e Immunologia, Instituto de Biologia, Unicamp, Cidade Universitrária Zeferino Vaz s/n, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br The presence of iron uptake (irp-2, fyuA, sitA, fepC, iucA), adhesion (iha, lpfAO157/O141, lpfAO157/O154, efa, toxB) and invasion (inv, ial-related DNA sequences and assignment to the four main Escherichia coli phylogenetic groups (A, B1, B2 e D) were determined in 30 commensal E. coli strains isolated from healthy chickens and in 49 APEC strains isolated from chickens presenting clinical signs of septicemia (n=24) swollen head syndrome (n=14) and omphalitis (n=11) by PCR. None of the strains presented DNA sequences related to the inv, ial, efa, and toxB genes. DNA sequences related to lpfAO157/O154, iucA, fepC, and irp-2 genes were significantly found among pathogenic strains, where iucA gene was associated with septicemia and swollen head syndrome and fepC and irp-2 genes were associated with swollen head syndrome strains. Phylogenetic typing showed that commensal and omphalitis strains belonged mainly to phylogenetic Group A and swollen head syndrome to phylogenetic Group D. Septicemic strains were assigned in phylogenetic Groups A and D. These data could suggest that clonal lineage of septicemic APEC strains have a multiple ancestor origin; one from a pathogenic bacteria ancestor and other from a non-pathogenic ancestor that evolved by the acquisition of virulence related sequences through horizontal gene transfer. Swollen head syndrome may constitute a pathogenic clonal group. By the other side, omphalitis strains probably constitute a non-pathogenic clonal group, and could cause omphalitis as an opportunistic infection. The sharing of virulence related sequences by human pathogenic E. coli and APEC strains could indicate that APEC strains could be a source of virulence genes to human strains and could represent a zoonotic risk.


#13 - Detection and phylogenetic analysis of porcine enteric calicivirus, genetically related to the Cowden strain of sapovirus genogroup III, in Brazilian swine herds, p.82-86

Abstract in English:

Abstract.- Barry A.F, Alfieri A.F. & Alfieri A.A. 2008. Detection and phylogenetic analysis of porcine enteric calicivirus, genetically related to the Cowden strain of sapovirus genogroup III, in Brazilian swine herds. Pesquisa Veterinária Brasileira 28(1):82-86. Laboratório de Virologia Animal, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Agrárias, Universidade Estadual de Londrina, Campus Universitário, Londrina, PR 86051-990, Brazil. E-mail: alinebarry@uol.com.br Sapovirus of the Caliciviridae family is an important agent of acute gastroenteritis in children and piglets. The Sapovirus genus is divided into seven genogroups (G), and strains from the GIII, GVI and GVII are associated with infections in swine. Despite the high prevalence in some countries, there are no studies related to the presence of porcine enteric sapovirus infections in piglets in Brazil. In the present study, 18 fecal specimens from piglets up to 28 days were examined to determine the presence of sapovirus genome by RT-PCR assay, using primers designed to amplify a 331 bp segment of the RNA polymerase gene. In 44.4% (8/18) of fecal samples, an amplified DNA fragment was obtained. One of these fragments was sequenced and submitted to molecular and phylogenetic analysis. This analysis revealed high similarity, with nucleotides (87%) and amino acids (97.8%), to the Cowden strain, the GIII prototype of porcine enteric calicivirus. This is the first description of sapovirus in Brazilian swine herds.

Abstract in Portuguese:

Abstract.- Barry A.F, Alfieri A.F. & Alfieri A.A. 2008. Detection and phylogenetic analysis of porcine enteric calicivirus, genetically related to the Cowden strain of sapovirus genogroup III, in Brazilian swine herds. Pesquisa Veterinária Brasileira 28(1):82-86. Laboratório de Virologia Animal, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Agrárias, Universidade Estadual de Londrina, Campus Universitário, Londrina, PR 86051-990, Brazil. E-mail: alinebarry@uol.com.br Sapovirus of the Caliciviridae family is an important agent of acute gastroenteritis in children and piglets. The Sapovirus genus is divided into seven genogroups (G), and strains from the GIII, GVI and GVII are associated with infections in swine. Despite the high prevalence in some countries, there are no studies related to the presence of porcine enteric sapovirus infections in piglets in Brazil. In the present study, 18 fecal specimens from piglets up to 28 days were examined to determine the presence of sapovirus genome by RT-PCR assay, using primers designed to amplify a 331 bp segment of the RNA polymerase gene. In 44.4% (8/18) of fecal samples, an amplified DNA fragment was obtained. One of these fragments was sequenced and submitted to molecular and phylogenetic analysis. This analysis revealed high similarity, with nucleotides (87%) and amino acids (97.8%), to the Cowden strain, the GIII prototype of porcine enteric calicivirus. This is the first description of sapovirus in Brazilian swine herds.


#14 - Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region

Abstract in English:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.

Abstract in Portuguese:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.


#15 - Lentiviruses of small ruminants (CAEV and Maedi-Visna): a review and perspectives, 21(3):87-97

Abstract in English:

ABSTRACT.- Callado A.K.C., Castro R.S. & Teixeira M.F.S. 2001. [Lentiviruses of small ruminants (CAEV and Maedi-Visna): a review and perspectives] Lentivírus de pequenos ruminantes (CAEV e Maedi-Visna): revisão e perspectivas. Pesquisa Veterinária Brasileira 21(3):87-97. Depto Medicina Veterinária, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros s/n, Dois Irmãos, Recife, PE 55171-000, Brazil. E-mail: callado@altavista.net Small ruminant lentiviruses (SRLV), whose prototypes are Caprine Arthritis-Encephalitis virus (CAEV) and Maedi-Visna virus, are the causative agents of slow progressive degenerative diseases of goats and sheep (infected animals), responsible for significant economic losses. These viruses cause persistent infections with long periods of incubation and induce inflammatory and degenerative lesions. The lesions are induced in target organs of the host such as joints, CNS, lungs and mammary glands dueto viral replication in cells of the monocyte/macrophage lineage which is the main target cell. Infections occur particularly in the young and are acquired through ingestion of virus in milk or colostrum from infected does or ewes. The induction of immune response is variable and does not protect against the infection. Diagnosis is primarily based on the presence of SRLV antibodies usually detected by agar gel immunodiffusion (AGID) or enzyme linked immunosorbent assays (ELISA). As no vaccine is available, most often employed schemes to prevent spread of SRLV are based on segregation or/and culling of positive animals associated with management practices, especially the offspring. The strategies of SRLV for dealing with the immune system make difficult to accomplish diagnosis of infection, control or prevention of the viral spread. This review shows aspects of SRLV based on their phylogenetic studies of fields isolates, clinical, and immunopathological features.

Abstract in Portuguese:

RESUMO.- Callado A.K.C., Castro R.S. & Teixeira M.F.S. 2001. [Lentiviruses of small ruminants (CAEV and Maedi-Visna): a review and perspectives] Lentivírus de pequenos ruminantes (CAEV e Maedi-Visna): revisão e perspectivas. Pesquisa Veterinária Brasileira 21(3):87-97. Depto Medicina Veterinária, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros s/n, Dois Irmãos, Recife, PE 55171-000, Brazil. E-mail: callado@altavista.net Os lentivírus de pequenos ruminantes (SRLV), cujos protótipos são os vírus da Artrite-Encefalite Caprina (CAEV) e Maedi-Visna, são patógenos amplamente distribuidos, os quais causam doenças degenerativas progressivas lentas em caprinos e ovinos, determinando importantes perdas econômicas. Estes vírus causam infecções persistentes com período de incubação longo e causam inflamatórias e degenerativas. As lesões são induzidas em tecidos específicos do hospedeiro como articulações, pulmões, CNS e glândulas mamárias devido à replicação virai em células da linhagem monocítico-fagocitária que são as principais células-alvo. A infecção ocorre principalmente durante os primeiros meses de vida, através da ingestão de vírus no leite ou colostro de cabras ou ovelhas infectadas. A indução da resposta imunológica é variável e não protege contra a infecção. O diagnóstico é baseado primariamente na detecção de anticorpos para SRLV, geralmente por imunodifusão em gel de agar (AGID) e enzyme linked immunosorbent assay (ELISA). O diagnóstico e separação ou descarte dos animais soropositivos associado ao uso de certas práticas de manejo, especialmente das crias, são os principais meios implementados para prevenir a disseminação de SRLV, uma vez que ainda não existe vacina contra o vírus. As estratégias adotadas pelos SRLV para enfrentar o sistema imune dificultam o diagnóstico da infecção, controle ou prevenção da disseminação de SRLV. Esta revisão apresenta alguns aspectos das lentivíroses de pequenos ruminantes baseadas em estudos filogenéticos de amostras isoladas, aspectos clínicos e imunopatológicos.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV