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1.
Clin Microbiol Infect ; 24(6): 646-652, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29133154

RESUMO

OBJECTIVES: We aimed to report the first 54 cases of pregnant women infected by Zika virus (ZIKV) and their virologic and clinical outcomes, as well as their newborns' outcomes, in 2016, after the emergence of ZIKV in dengue-endemic areas of São Paulo, Brazil. METHODS: This descriptive study was performed from February to October 2016 on 54 quantitative real-time PCR ZIKV-positive pregnant women identified by the public health authority of São José do Rio Preto, São Paulo, Brazil. The women were followed and had clinical and epidemiologic data collected before and after birth. Adverse outcomes in newborns were analysed and reported. Urine or blood samples from newborns were collected to identify ZIKV infection by reverse transcription PCR (RT-PCR). RESULTS: A total of 216 acute Zika-suspected pregnant women were identified, and 54 had the diagnosis confirmed by RT-PCR. None of the 54 women miscarried. Among the 54 newborns, 15 exhibited adverse outcomes at birth. The highest number of ZIKV infections occurred during the second and third trimesters. No cases of microcephaly were reported, though a broad clinical spectrum of outcomes, including lenticulostriate vasculopathy, subependymal cysts, and auditory and ophthalmologic disorders, were identified. ZIKV RNA was detected in 18 of 51 newborns tested and in eight of 15 newborns with adverse outcomes. CONCLUSIONS: Although other studies have associated many newborn outcomes to ZIKV infection during pregnancy, these same adverse outcomes were rare or nonexistent in this study. The clinical presentation the newborns we studied was mild compared to other reports, suggesting that there is significant heterogeneity in congenital Zika infection.


Assuntos
Doenças Fetais/virologia , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/complicações , Zika virus/isolamento & purificação , Adulto , Brasil , Feminino , Humanos , Recém-Nascido , Filogenia , Gravidez , Adulto Jovem , Zika virus/classificação , Zika virus/genética
2.
Parasite Immunol ; 39(10)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28836673

RESUMO

This study evaluated levels for mRNA expression of 7 cytokines in ocular toxoplasmosis. Peripheral blood mononuclear cells (PBMC) of patients with ocular toxoplasmosis (OT Group, n = 23) and chronic toxoplasmosis individuals (CHR Group, n = 9) were isolated and stimulated in vitro with T. gondii antigen. Negative controls (NC) were constituted of 7 PBMC samples from individuals seronegative for toxoplasmosis. mRNA expression for cytokines was determined by qPCR. Results showed a significant increase in mRNA levels from antigen stimulated PBMCs derived from OT Group for expressing IL-6 (at P < .005 and P < .0005 for CHR and NC groups, respectively), IL-10 (at P < .0005 and P < .005 for CHR and NC groups, respectively) and TGF-ß (at P < .005) for NC group. mRNA levels for TNF-α and IL-12 were also upregulated in patients with OT compared to CHR and NC individuals, although without statistical significance. Additionally, mRNA levels for IL-27 and IFN-γ in PBMC of patients with OT were upregulated in comparison with NC individuals. Differences between OT and NC groups were statistically significant at P < .05 and P < .0005, respectively.


Assuntos
Antígenos de Protozoários/imunologia , Citocinas/genética , Leucócitos Mononucleares/imunologia , RNA Mensageiro/biossíntese , Toxoplasma/imunologia , Toxoplasmose Ocular/imunologia , Citocinas/metabolismo , Expressão Gênica , Humanos , Estudos Prospectivos , Toxoplasmose Ocular/diagnóstico , Toxoplasmose Ocular/parasitologia
3.
Vox Sang ; 108(3): 281-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25469787

RESUMO

BACKGROUND AND OBJECTIVES: The red blood cell Le(a-b-) phenotype was proposed as risk factor for type 1 diabetes, but contradictory results were published elsewhere. This study re-examined the potential association between Lewis histo-blood group system and type 1 diabetes. MATERIAL AND METHODS: Patients and controls of both sexes, Caucasians and non-Caucasians, matched by sex, geographical origin and ethnicity were evaluated. The red blood cell Lewis phenotypes were identified by gel column agglutination and also inferred from the FUT2 and FUT3 genotyping. RESULTS: The Le(a-b-) phenotype was prevalent in patients with type 1 diabetes, and the Le(a-b+) phenotype was prevalent in controls when both were determined by gel columns agglutination. No differences were observed in the frequencies of the Le(a-b-) phenotype inferred from the FUT2 and FUT3 genotyping between patients and controls. CONCLUSIONS: The Lewis red blood cell phenotyping and genotyping reveal divergence in the association of Le(a-b-) phenotype and type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Genótipo , Antígenos do Grupo Sanguíneo de Lewis/genética , Fenótipo , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Fucosiltransferases/genética , Humanos , Masculino , Pessoa de Meia-Idade , Galactosídeo 2-alfa-L-Fucosiltransferase
4.
Int J Immunogenet ; 42(1): 19-25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25418108

RESUMO

The aim of this study was to estimate the HLA-A, HLA-B and HLA-DRB1 allele groups frequencies in a population of 1559 volunteer bone marrow donors from the northwestern region of São Paulo State grouped according to ethnicity. An additional objective was to compare the allele frequencies of the current study with data published for other Brazilian populations. The allele groups were characterized by the PCR-rSSO method using Luminex(®) technology. Twenty HLA-A, 32 HLA-B and 13 HLA-DRB1 allele groups were identified. The most common allele groups in European descent and mixed African and European descent samples were HLA-A*02, HLA-B*35 and HLA-DRB1*13, while HLA-A*02, HLA-B*35 and HLA-DRB1*11 were more common in African descent samples. The HLA-A*23, HLA-A*36, HLA-B*58 and HLA-B*81 allele groups were more common in sample from African descent than European descent, and the HLA-DRB1*08 was more common in mixed African and European descent than in European descent. Allele group frequencies were compared with samples from other Brazilian regions. The HLA-A*30 and HLA-A*23 were more common in this study than in the populations of Rio Grande do Sul and Paraná; and the HLA-A*01, HLA-B*18, HLA-B*57 and HLA-DRB1*11 were more common in this study than in the population of Piauí. The least frequent allele groups were HLA-A*31, HLA-B*15, HLA-B*40 and HLA-DRB1*08 for the population of Piauí, HLA-A*01 and HLA-A*11 for Parana, HLA-A*02 and -A*03 for Rio Grande do Sul and HLA-DRB1*04 for Paraná, Rio Grande do Sul and Piauí. These data provide an overview on the knowledge on HLA diversity in the population of the northwestern region of São Paulo State and show that the genes of this system are useful to distinguish different ethnic groups.


Assuntos
Frequência do Gene/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Alelos , População Negra/genética , Medula Óssea , Transplante de Medula Óssea , Brasil , Genética Populacional , Humanos , Polimorfismo Genético/genética , População Branca/genética
5.
Epidemiol Infect ; 142(1): 142-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23507508

RESUMO

The aim of this study was to investigate risk factors for ocular toxoplasmosis (OT) in patients who received medical attention at a public health service. Three hundred and forty-nine consecutive patients, treated in the Outpatient Eye Clinic of Hospital de Base, São José do Rio Preto, São Paulo state, Brazil, were enrolled in this study. After an eye examination, enzyme-linked immunosorbent assay (ELISA) was used to determine anti-Toxoplasma gondii antibodies. The results showed that 25.5% of the patients were seronegative and 74.5% were seropositive for IgG anti-T. gondii antibodies; of these 27.3% had OT and 72.7% had other ocular diseases (OOD). The presence of cats or dogs [odds ratio (OR) 2.22, 95% confidence interval (CI) 1.24-3.98, P = 0.009] and consumption of raw or undercooked meat (OR 1.77, 95% CI 1.05-2.98, P = 0.03) were associated with infection but not with the development of OT. Age (OT 48.2 ± 21.2 years vs. OOD: 69.5 ± 14.7 years, P < 0.0001) and the low level of schooling/literacy (OT vs. OOD: OR 0.414, 95% CI 0.2231-0.7692, P = 0.007) were associated with OT. The presence of dogs and cats as well as eating raw/undercooked meat increases the risk of infection, but is not associated with the development of OT.


Assuntos
Toxoplasmose Ocular/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Toxoplasma/imunologia , Toxoplasmose Ocular/imunologia
6.
Epidemiol Infect ; 141(7): 1552-61, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23433340

RESUMO

Forty-five human rabies virus isolates from a wide geographical area of Brazil were characterized using an anti-nucleoprotein monoclonal antibody panel and by partial nucleotide sequencing analysis of the nucleoprotein gene. Three major antigenic groups related to the antigenic variants maintained in domestic dogs, vampire bats and marmosets were identified. Phylogenetic analyses revealed that the viruses from dog-related cases segregated into four sister clades: three associated with dog-endemic cycles in Brazil and one with the crab-eating fox cycle in the northeastern region of the country. The vampire bat- and marmoset-related viruses formed two independent groups. The topology of these clades was conserved when these samples were compared to virus representatives of the currently reported rabies endemic cycles in the Americas. These results indicated the presence of multiple endemic transmission cycles maintained in four different reservoirs, domestic dogs, crab-eating foxes, vampire bats and marmosets, which are being transmitted directly to humans and should be considered as a high-risk for rabies infection.


Assuntos
Vírus da Raiva/genética , Raiva/transmissão , Raiva/veterinária , Zoonoses/transmissão , Sequência de Aminoácidos , Animais , Antígenos Virais/análise , Brasil , Callithrix/virologia , Quirópteros/virologia , DNA Viral/análise , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Doenças do Cão/transmissão , Doenças do Cão/virologia , Cães , Raposas/virologia , Humanos , Dados de Sequência Molecular , Doenças dos Macacos/transmissão , Doenças dos Macacos/virologia , Filogenia , Raiva/virologia , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Zoonoses/virologia
7.
Genet Mol Res ; 11(2): 1178-84, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22614344

RESUMO

Genes located outside the HLA region (6p21) have been considered as candidates for susceptibility to ankylosing spondylitis. We tested the hypothesis that the G22A polymorphism of the adenosine deaminase gene (ADA; 20q13.11) is associated with ankylosing spondylitis in 166 Brazilian subjects genotyped for the HLA*27 gene (47 patients and 119 controls matched for gender, age and geographic origin). The HLA-B*27 gene and the G22A ADA polymorphism were identified by PCR with sequence-specific oligonucleotide probes and PCR-RFLP, respectively. There were no significant differences in frequencies of ADA genotypes [odds ratio (OR) = 1.200, 95% confidence interval (CI) = 0.3102-4.643, P > 0.8] and ADA*01 and ADA*02 alleles (OR = 1.192, 95%CI = 0.3155-4.505, P > 0.8) in patients versus controls. We conclude that the G22A polymorphism is not associated with ankylosing spondylitis.


Assuntos
Adenosina Desaminase/genética , Polimorfismo Genético , Espondilite Anquilosante/genética , Adulto , Sequência de Bases , Estudos de Casos e Controles , Primers do DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J. venom. anim. toxins incl. trop. dis ; 17(2): 184-189, 2011. tab
Artigo em Inglês | LILACS | ID: lil-587778

RESUMO

Toxoplasma gondii infects humans through the gastrointestinal tract (GIT), which elicits humoral immune response with specific antibodies. The expression of the ABO blood group glycoconjugates also occurs in this same system and may influence the human susceptibility of infection by T. gondii. The aim of the present study was to investigate the association between ABO blood group phenotypes and the presence of anti-T. gondii antibodies. Data - including age, results of serology tests for T. gondii infection and ABO blood group phenotypes - were assembled from the medical records of 1,006 pregnant women attended in the Base Hospital of the Medical School of São José do Rio Preto, Brazil, between 2001 and 2004. The chi-square test was used to compare the results with the level of significance set at 5 percent. Of the studied cases, 64.1 percent (645/1006) and 35.9 percent (391/1006) presented respectively positive and negative serology tests for anti-T. gondii antibodies. The mean age of those who tested positive was higher than those with negative serology tests (p = 0.0004). The frequencies of ABO blood group phenotypes were similar in those with and without anti-T. gondii antibodies (p = 0.35). In conclusion, the ABO blood group system is not associated with the presence or absence of anti-T. gondii antibodies.


Assuntos
Humanos , Feminino , Sistema ABO de Grupos Sanguíneos , Gestantes , Toxoplasma , Toxoplasmose/sangue
9.
Artigo em Inglês | LILACS | ID: lil-542431

RESUMO

Diseases resulting from Helicobacter pylori infection appear to be dependent on a host of genetic traits and virulence factors possessed by this microorganism. This paper aimed to investigate the association between the ABO histo-blood groups and H. pylori cagA infections. Genomic DNA samples (n = 110) of gastric biopsies obtained from patients with endoscopic diagnosis of peptic ulcers (n = 25) and chronic active gastritis (n = 85) were analyzed by PCR using specific primers for the cagA gene. Of the samples, 66.4 percent (n = 73) tested positive and 33.6 percent (n = 37) negative for the gene. The cagA strain was predominant in peptic ulcers (n = 21; 84.0 percent) compared with chronic active gastritis (n = 52; 61.2 percent) (p = 0.05; OR 3.332; 95 percent CI: 1.050-10.576). Additionally, the cagA strain was prevalent in the type O blood (48/63; 76.2 percent) compared with other ABO phenotypes (25/47; 53.2 percent) (p = 0.01; OR 2.816; 95 percent CI: 1.246-6.364). These results suggest that H. pylori cagA infection is associated with the O blood group in Brazilian patients suffering from chronic active gastritis and peptic ulcers.


Assuntos
Humanos , Masculino , Feminino , Sistema ABO de Grupos Sanguíneos , Gastrite/sangue , Helicobacter pylori , Infecções por Helicobacter/genética , Úlcera Péptica/sangue
10.
Emerg Infect Dis ; 7(6): 1062-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11747745

RESUMO

A new Rabies virus variant, with no close antigenic or genetic relationship to any known rabies variants found in bats or terrestrial mammals in the Americas, was identified in association with human rabies cases reported from the state of Ceará, Brazil, from 1991 to 1998. The marmoset, Callithrix jacchus acchus, was determined to be the source of exposure.


Assuntos
Callithrix , Reservatórios de Doenças/veterinária , Doenças dos Macacos/virologia , Raiva/veterinária , Adolescente , Adulto , Animais , Antígenos Virais/imunologia , Brasil , Feminino , Humanos , Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo , Filogenia , Raiva/virologia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Vírus da Raiva/imunologia
11.
J Wildl Dis ; 36(2): 231-40, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10813604

RESUMO

One hundred and five rabies isolates obtained from domestic animals and insectivorous bats in Chile between 1977 and 1998 were molecularly characterized by limited sequence analysis of their nucleoprotein genes. These isolates were compared with viruses isolated from known domestic and wildlife rabies reservoirs in the Americas to identify potential reservoirs of rabies in Chile. The phylogenetic analyses showed that none of the Chilean isolates segregated with viruses from the terrestrial reservoirs. No non-rabies lyssaviruses were found in this study. The Chilean samples were not related to viruses of the sylvatic cycle maintained by the common vampire bat (Desmodus rotundus) in Latin America. Five genetic variants were identified from insectivorous bats in Chile. The Brazilian free-tailed bat (Tadarida brasiliensis) was identified as the reservoir for the rabies genetic variant most frequently isolated in the country between 1977 and 1998. The close association of a group of viruses obtained from a domestic dog (Canis familiaris), Brazilian free-tailed bats, and a red bat (Lasiurus borealis) with viruses maintained by Lasiurus spp. in North America implicated species of this genus as the possible reservoirs of this particular genetic variant in Chile. Reservoirs for the other three variants remain unknown.


Assuntos
Quirópteros , Reservatórios de Doenças/veterinária , Vírus da Raiva/classificação , Raiva/veterinária , Animais , Chile/epidemiologia , Filogenia , Raiva/epidemiologia , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Saúde da População Urbana
12.
Am J Trop Med Hyg ; 61(4): 587-97, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10548293

RESUMO

Twenty-eight samples from humans and domestic and wild animals collected in Mexico between 1990 and 1995 were characterized by using anti-nucleoprotein monoclonal antibodies and limited sequence analysis of the nucleoprotein gene. The variants of rabies viruses identified in these samples were compared with other isolates from Mexico and the rest of the Americas to establish epidemiologic links between cases and outbreaks and to increase the understanding of rabies epidemiology in the Western Hemisphere. Antigenic and genetic diversity was found in all samples from dogs and dog-related cases, suggesting a long-term endemic situation with multiple, independent cycles of virus transmission. Two isolates from bobcats were antigenically and genetically homologous to the rabies variant circulating in the Arizona gray fox population, indicating a wider distribution of this variant than previously reported. Rabies isolates from skunks were unrelated to any variant analyzed in this study and represent a previously unrecognized cycle of rabies transmission in skunks in Baja California Sur. Two antigenic and genetic variants co-circulating in southern and eastern Mexico were found in viruses obtained from cases epidemiologically related to vampire bats. These results serve as a baseline for the better understanding of the molecular epidemiology of rabies in Mexico.


Assuntos
Variação Antigênica/genética , Doenças do Cão/epidemiologia , Variação Genética , Vírus da Raiva/genética , Raiva/veterinária , Animais , Anticorpos Monoclonais , Sequência de Bases , Carnívoros , Quirópteros , Sequência Consenso , Primers do DNA/química , DNA Viral/química , Doenças do Cão/transmissão , Doenças do Cão/virologia , Cães , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Raposas , Humanos , Mephitidae , México/epidemiologia , Dados de Sequência Molecular , Filogenia , RNA Viral/isolamento & purificação , Raiva/epidemiologia , Raiva/transmissão , Vírus da Raiva/classificação , Vírus da Raiva/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Alinhamento de Sequência , Análise de Sequência de DNA
13.
J Virol ; 70(8): 5735-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8764098

RESUMO

To better define the molecular epidemiology of bluetongue virus (BTV) infection, the genetic characteristics and phylogenetic relationships of the S3 genes of the five U.S. prototype strains of BTV, the commercially available serotype 10 modified live virus vaccine, and 18 field isolates of BTV serotypes 10, 11, 13, and 17 obtained in California during 1980, 1981, 1989, and 1990 were determined. With the exception of the S3 gene of the U.S. prototype strain of BTV serotype 2 (BTV 2), these viruses had an overall sequence homology of between 95 and 100%. Phylogenetic analyses segregated the prototype U.S. BTV 2 strain to a unique branch (100% bootstrap value), whereas the rest of the viruses clustered in two main monophyletic groups that were not correlated with their serotype, year of isolation, or geographical origin. The lack of consistent association between S3 gene sequence and virus serotype likely is a consequence of reassortment of BTV gene segments during natural mixed infections of vertebrate and invertebrate hosts. The prototype strain of BTV 13, which is considered an introduction to the U.S. like BTV 2, presents an S3 gene which is highly homologous to those of some isolates of BTV 10 and especially to that of the vaccine strain. This finding strongly suggests that the U.S. prototype strain of BTV 13 is a natural reassortant. The different topologies of the phylogenetic trees of the L2 and S3 genes of the various viruses indicate that these two genome segments evolve independently. We conclude that the S3 gene segment of populations of BTV in California is formed by different consensus sequences which cocirculate and which cannot be grouped by serotype.


Assuntos
Vírus Bluetongue/genética , Genes Virais , California , Filogenia , Estados Unidos
14.
Comp Immunol Microbiol Infect Dis ; 19(3): 181-90, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8800543

RESUMO

Prototype and field isolates of United States bluetongue viruses were evaluated for genetic heterogeneity by sequence analyses. Prototype viruses BTV 2, 10, 11, 13 and 17 from the United States, BTV 10 vaccine virus, and field isolates of BTV 10 and 17 from California were analyzed. Gene segment 2 from BTV 10 and 17 isolated in 1980-81 and 1990 was sequenced along with gene segment 9 from BTV 10 isolates. The Wisconsin Package was used to analyze nucleotide sequences and to predict amino acid composition of the putative proteins. Phylogenetic analyses were done using DNADIST and FITCH programs of the PHYLIP Package, v. 3.4. Gene segment 2 segregated into two monophyletic groups of BTV 2 and 13 and BTV 10, 11 and 17. BTV prototype 10, isolated in 1953 and field isolates through 1980 were similar, whereas the 1990 isolates differed by 4.5%, indicating two BTV 10 monophyletic groups over 37 years. Gene segment 2 of BTV 17 prototype virus differed from the California isolates. Gene segment 9 of BTV 10 field isolates formed into two monophyletic groups. This gene segment reassorted with all serotypes. Gene segment 9 of the 1953 BTV 10 vaccine virus was essentially the same as gene segment 9 of the BTV 13 prototype virus, isolated in Idaho in 1967. This suggested that prototype BTV 13 is a reassortant virus with gene segment 9 derived from a vaccine virus parent.


Assuntos
Vírus Bluetongue/genética , Bluetongue/virologia , Variação Genética/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bluetongue/epidemiologia , California/epidemiologia , Bovinos , Cabras , Idaho/epidemiologia , Mutação/genética , Filogenia , Ovinos , Wyoming/epidemiologia
15.
J Clin Microbiol ; 34(6): 1553-8, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8735118

RESUMO

Twenty samples from cases of rabies in humans and domestic animals diagnosed in Venezuela between 1990 and 1994 and one sample from a vampire bat collected in 1976 were characterized by reactivity to monoclonal antibodies against the viral nucleoprotein and by patterns of nucleotide substitution in the nucleoprotein gene. Three antigenic variants were found: 1, 3, and 5. Antigenic variant 1 included all samples from dogs and humans infected by contact with rabid dogs. Unique substitutions permitted identification of two separate outbreaks of dog rabies in the Maracaibo Depression and Los Llanos region and in the Andean region of Venezuela. Samples from the vampire bat and two head of cattle were characterized as antigenic variant 3 and showed a nucleotide sequence homology of 96 to 98% to each other and to samples of vampire bat-associated rabies throughout Latin America. Ten of the remaining 12 samples were characterized as antigenic variant 5. Genetic studies indicated that 11 of these samples formed a highly homologous and distinctive group but were closely related to samples of vampire bat-associated rabies. The 12th sample of variant 5 (from a cat) showed only 78 to 80% genetic homology to samples of rabies associated with vampire bats. The application of antigenic and genetic typing to rabies surveillance in Latin America is essential to improve control programs. Recognition of the source of outbreaks of dog rabies and identification of wildlife species maintaining sylvatic cycles of rabies transmission permit better utilization of public health resources.


Assuntos
Vírus da Raiva/genética , Animais , Anticorpos Monoclonais , Variação Antigênica , Antígenos Virais/genética , Sequência de Bases , Gatos , Bovinos , Quirópteros , DNA Viral/genética , Surtos de Doenças/veterinária , Reservatórios de Doenças , Cães , Genes Virais , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Raiva/epidemiologia , Raiva/veterinária , Raiva/virologia , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Homologia de Sequência do Ácido Nucleico , Venezuela/epidemiologia , Proteínas Virais/genética , Proteínas Virais/imunologia
16.
Virology ; 201(1): 173-7, 1994 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8178484

RESUMO

The genetic characteristics and phylogenetic relationships between the U.S. prototype strain of bluetongue virus serotype 10 (BTV 10), the modified live virus vaccine currently used in California, and three field isolates of BTV 10 obtained in 1980 and three in 1990 in California were determined by comparison of their L2 gene sequences. The L2 genes of the 1980 field isolates were very closely related to the L2 genes of the prototype strain and the vaccine strain, differing by only 0.1 to 0.5%. The 1990 field isolates diverged from all the other viruses by an average of 4.8%. They showed a high degree of genetic similarity that ranged from 98.2 to 99.7% and formed a separate group. All BTV 10 viruses derived from a common ancestor (bootstrap value 100%) from which two different lineages have diverged giving rise to two monophyletic groups, one including all the 1990 viruses and the other the prototype, the vaccine, and all 1980 field strains. The bootstrap analyses placed a 100% confidence value at each of these two nodes. These results indicate that two different lineages of BTV 10 circulated in California between 1953 and 1990. The effect of the vaccine on the evolutionary pathways of the BTV 10 population present in California in 1980 was not clearly established, but it did not influence the evolution of the BTV 10 field isolates obtained in 1990.


Assuntos
Evolução Biológica , Vírus Bluetongue/genética , Capsídeo/genética , Genes Virais/genética , Proteínas Estruturais Virais/genética , Sequência de Bases , Vírus Bluetongue/classificação , Vírus Bluetongue/imunologia , California , Proteínas do Capsídeo , Sequência Conservada , DNA Complementar , Variação Genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Vacinas Virais/genética
17.
J Virol ; 68(2): 1255-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8289361

RESUMO

Two strains (UC-2 and UC-8) of bluetongue virus were used to determine genetic factors influencing neuroinvasiveness. Reassortants were produced in vitro, and the parental origins of their genes were determined by polyacrylamide gel electrophoresis profiles and restriction endonuclease digestion. Gene segment 5 of UC-8 correlated with neuroinvasiveness of reassortants when inoculated subcutaneously into newborn mice.


Assuntos
Vírus Bluetongue/genética , Vírus Bluetongue/patogenicidade , Bluetongue/microbiologia , Encéfalo/microbiologia , Genes Virais/genética , Animais , Animais Recém-Nascidos , Sequência de Bases , Bovinos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Células Vero
18.
Virus Res ; 31(1): 67-87, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8165870

RESUMO

Genome segment 2 (L2) from six field isolates of bluetongue virus (BTV) serotype 17 was sequenced by cycling sequencing after the amplification of the viral cDNA by the polymerase chain reaction. The viruses were isolated from sheep, cattle and a goat in the San Joaquin Valley of California during the years 1981 and 1990. These viruses exhibit divergent patterns of neutralization with BTV 17-specific monoclonal antibodies. The six L2 genes of the BTV 17 field isolates all encode a protein of 955 amino acids. Similarity of the nucleotide sequences of the L2 genes with respect to the prototype strain ranges between 93.8% and 95.1%, whereas the similarity between the field isolates ranges from 96.8% to 99.1%. Although very closely related, the L2 gene of each virus is distinct. Furthermore, mutations in the L2 gene of field isolates of BTV do not consistently follow a linear pattern of accumulation over time. Some amino acid changes in the VP2 protein of field strains were conserved over time, whereas others were not correlated with the year of isolation and some substitutions were unique to individual viruses. The predicted VP2s constitute a group of non-identical, but closely related proteins. Phylogenetic analyses suggest that the viral variants which co-circulate in the San Joaquin Valley could evolve by different evolutionary pathways.


Assuntos
Vírus Bluetongue/genética , Capsídeo/genética , Genes Virais , Variação Genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bluetongue/microbiologia , California , Proteínas do Capsídeo , Dados de Sequência Molecular , Mutação/genética , Filogenia , Ruminantes/microbiologia , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Am J Vet Res ; 53(12): 2245-50, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1335705

RESUMO

A slot blot hybridization technique was applied for detection of bluetongue virus (BTV) in blood mononuclear cells (BMNC) obtained from cattle with experimentally induced infection. This technique lacked sensitivity to detect the viral nucleic acid directly in clinical specimens. When aliquots of mononuclear cells from these cattle were cultivated in vitro for 10 days to amplify virus titer, only 33.3% of the samples collected during viremia gave a positive signal in the slot blot hybridization format. By contrast, results for 34.3% of noncultured and 63.3% of cultured mononuclear cell samples collected during viremia were positive by immunofluorescence. The average number of infected cells, as detected by immunofluorescence in the noncultured mononuclear cell samples, was 1 to 5/300,000, and was usually > 10/300,000 in the cultured cell samples. Virus was isolated from all postinoculation blood samples obtained from 4 heifers that were seronegative at the time of inoculation, but was not isolated from any of the preinoculation samples, or from any of the postinoculation samples obtained from 2 heifers that were seropositive at the time of inoculation. When virus isolation was attempted from separated mononuclear cells in 2 heifers, 43.7% of the noncultured and 87.5% of the cultured samples had positive results.


Assuntos
Vírus Bluetongue/isolamento & purificação , Bluetongue/microbiologia , Doenças dos Bovinos/microbiologia , Leucócitos Mononucleares/microbiologia , Animais , Bovinos , Feminino , Imunofluorescência/veterinária , Hibridização de Ácido Nucleico/veterinária , RNA Viral/sangue
20.
Arch Virol ; 122(1-2): 23-33, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1309643

RESUMO

Partial cDNA clones representing 47%, 96%, and 98% of genome segments 7, 9, and 10, respectively, of a US bluetongue virus (BLU) 11 virulent strain were used to study, for the first time, the genetic relationships between Israeli BLU proto-serotypes and field isolates, and US BLU proto-serotypes. Their usefulness as group-specific identification probes was also determined. The viral nucleic acid was extracted from the infected cells and the purified dsRNA genome segments were fractionated by polyacrylamide gel electrophoresis, transferred to a nylon membrane and hybridized to the 32P labeled DNA probes. The three probes recognized all the samples tested. Genome segment 7, that code for the mayor inner capsid protein VP7, showed the most variation in the hybridization signal with the US proto-serotypes and all the Israeli samples studied. The genome segments 9 and 10 that code for the minor inner capsid protein VP6 and the nonstructural protein NS3, respectively, were highly conserved in all the samples tested despite their distant geographical regions of origin. The last two mentioned clones showed to be good group-specific probes for the identification of BLU samples from Israel and United States. The obtained cloned genetic probes were also tested against US epizootic haemorrhagic disease virus (EHDV) serotype 1 and 2 viral dsRNA, a distantly related orbivirus. None of them hybridized with the viral dsRNA of these two viruses.


Assuntos
Vírus Bluetongue/classificação , Sondas de DNA , DNA Viral/genética , Animais , Sequência de Bases , Northern Blotting , Vírus Bluetongue/genética , Vírus Bluetongue/isolamento & purificação , Embrião de Galinha , Clonagem Molecular , Cabras/microbiologia , Israel , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA de Cadeia Dupla/isolamento & purificação , RNA Viral/isolamento & purificação , Ovinos/microbiologia , Especificidade da Espécie , Estados Unidos , Células Vero , Proteínas Virais/genética
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