Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Gene ; 855: 147131, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539044

RESUMO

Staphylococcus aureus is the main etiological agent of mastitis in small ruminants worldwide. This disease has a difficult cure and possible relapse, leading to significant economic losses in production, milk quality and livestock. This study performed comparative genomic analyses between 73 S. aureus genomes from different hosts (human, bovine, pig and others). This work isolated and sequenced 12 of these genomes from ovine. This study contributes to the knowledge of genomic specialization and the role of specific genes in establishing infection in ovine mastitis-associated S. aureus. The genomes of S. aureus isolated from sheep maintained a higher representation when grouped with clonal complexes 130 and 133. The genomes showed high genetic similarity, the species pan-genome consisting of 4200 genes (central = 2008, accessory = 1559 and unique = 634). Among these, 277 unique genes were related to the genomes isolated from sheep, with 39.6 % as hypothetical proteins, 6.4 % as phages, 6.4 % as toxins, 2.9 % as transporters, and 44.7 % as related to other proteins. Furthermore, at the pathogen level, they showed 80 genes associated with virulence factors and 19 with antibiotic resistance shared in almost all isolates. Although S. aureus isolated from ovine showed susceptibility to antimicrobials in vitro, ten genes were predicted to be associated with antibiotic inactivation and efflux pump, suggesting resistance to gentamicin and penicillin. This work may contribute to identifying genes acquired by horizontal transfer and their role in host adaptation, virulence, bacterial resistance, and characterization of strains affecting ovine.


Assuntos
Mastite Bovina , Infecções Estafilocócicas , Feminino , Animais , Bovinos , Ovinos/genética , Humanos , Suínos , Fatores de Virulência/genética , Staphylococcus aureus/genética , Adaptação ao Hospedeiro , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Ruminantes/genética , Genômica , Sequências Repetitivas Dispersas , Mastite Bovina/genética , Mastite Bovina/microbiologia
2.
Microbes Infect ; 25(1-2): 105018, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35940401

RESUMO

The Brucellaceae family comprises microorganisms similar both phenotypically and genotypically, making it difficult to identify the etiological agent of these infections. This study reports the first isolation, identification, and characterization of Pseudochrobactrum saccharolyticum (strain 115) from Latin America. Strain 115 was isolated in 2007 from a bovine in Brazil and was initially classified as Brucella spp. by classical microbiological tests and bcsp31 PCR. The antimicrobial susceptibility of strain 115 was tested against drugs used to treat human brucellosis by minimal inhibitory concentration test. Subsequently, the whole genome of the strain was sequenced, assembled, and characterized. Phylogenetic trees built from 16S rRNA and recA gene sequences enabled the classification of strain 115 as Pseudochrobactrum spp. Phylogenomic analysis using Single Nucleotide Polymorphisms and Average Nucleotide Identity allowed the classification of the strain as P. saccharolyticum. Additionally, a Tetra Correlation Search identified one related genome from the same species, which was compared with strain 115 by analyzing genomic islands. This is the first identification and whole-genome sequence of P. saccharolyticum in Latin America and highlights a challenge in the diagnosis of bovine brucellosis, which could be solved by including the sequencing of 16S rRNA and recA genes in routine diagnostics.


Assuntos
Brucellaceae , Animais , Bovinos , Humanos , RNA Ribossômico 16S/genética , Filogenia , América Latina , Brucellaceae/genética , DNA Bacteriano/genética
3.
Drug Chem Toxicol ; : 1-10, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36541066

RESUMO

Plant-derived chemicals are promising substances to control arthropod pests, although synthetic ones are still the most frequently used. Thus, comparative toxicological studies are needed to determine if natural substances are safe alternatives to replace the use of synthetic chemicals. This study aimed to compare the toxicity of carvacrol (natural origin), acetylcarvacrol (semi-synthetic) and a fipronil-based pesticide (synthetic). We assessed the effects of these chemicals on hemolytic activity, erythrocytes morphology and leucocyte viability using whole blood from human subjects. Additionally, DNA damage was evaluated through comet and DNA fragmentation assays. Fipronil and carvacrol caused hemolysis at concentrations ranging from 0.5 to 2.0%, whereas acetylcarvacrol did not cause hemolysis at 0.5 and 0.75%. Fipronil and carvacrol caused severe alterations in erythrocytes' morphology at 2%, such as ghost erythrocytes, elliptocyte-like shape and rouleau-like shape, presenting only 3.3 and 8.3% normal cells, respectively, at this concentration. However, 73.3% erythrocytes incubated with 2% acetylcarvacrol exhibited normal morphology. Fipronil considerably reduced leucocytes viability, decreasing it to 78% at 2%. Carvacrol and acetylcarvacrol showed no differences in leucocyte viability for 0.5 to 1.0%, but a decrease was observed for 2% carvacrol. The comet assay showed similar DNA damage for fipronil and carvacrol, but it was significantly lower for 1 and 2% acetylcarvacrol. Incubation with genomic DNA showed that only fipronil caused fragmentation of this molecule. Thus, we conclude that carvacrol and fipronil can present similar toxicity at higher concentrations. However, acetylation of carvacrol significantly reduced its toxicity to human blood cells compared with the other chemicals.

4.
PLoS One ; 10(7): e0132532, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26181775

RESUMO

This study aimed to determine the susceptibility profile of Brazilian Brucella abortus isolates from cattle to eight antimicrobial agents that are recommended for the treatment of human brucellosis and to correlate the susceptibility patterns with origin, biotype and MLVA16-genotype of the strains. Screening of 147 B. abortus strains showed 100% sensitivity to doxycycline and ofloxacin, one (0.68%) strain resistant to ciprofloxacin, two strains (1.36%) resistant to streptomycin, two strains (1.36%) resistant to trimethoprim-sulfamethoxazole and five strains (3.40%) resistant to gentamicin. For rifampicin, three strains (2.04%) were resistant and 54 strains (36.73%) showed reduced sensitivity. Two strains were considered multidrug resistant. In conclusion, the majority of B. abortus strains isolated from cattle in Brazil were sensitive to the antimicrobials commonly used for the treatment of human brucellosis; however, a considerable proportion of strains showed reduced susceptibility to rifampicin and two strains were considered multidrug resistant. Moreover, there was no correlation among the drug susceptibility pattern, origin, biotype and MLVA16-genotypes of these strains.


Assuntos
Antibacterianos/farmacologia , Brucella abortus/efeitos dos fármacos , Brucelose/tratamento farmacológico , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Rifampina/farmacologia , Animais , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Brucella abortus/classificação , Brucella abortus/genética , Brucella abortus/isolamento & purificação , Brucelose/epidemiologia , Brucelose/microbiologia , Bovinos , Ciprofloxacina/farmacologia , Doxiciclina/farmacologia , Genótipo , Gentamicinas/farmacologia , Estreptomicina/farmacologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia
5.
Semina Ci. agr. ; 34(3): 1281-1286, 2013.
Artigo em Português | VETINDEX | ID: vti-472805

RESUMO

Os objetivos deste trabalho foram (i) determinar a ocorrência da infecção por Brucella abortus em equídeos de vida livre no município de Mossoró, Rio Grande do Norte e (ii) avaliar possíveis fatores associados a esta infecção. Soros de 227 equídeos (178 asininos, 43 equinos e 6 muares), capturados pela polícia rodoviária e funcionários da prefeitura, foram coletados por punção venosa. A pesquisa de anticorpos anti-Brucella abortus foi realizada empregando-se, como triagem, o teste do antígeno acidificado tamponado (AAT) e como confirmatório o teste de redução pelo 2-Mercaptoetanol (2ME). Dos animais testados, quatro (1,76%) foram positivos para anticorpos anti- B. abortus. Todos os positivos eram equinos (9,30%, 4/43). A análise das variáveis levantadas (sexo e idade) como possíveis fatores associados à infecção por B. abortus não revelou a existência de associação entre estas e a soropositividade. Assim, o presente estudo permite concluir que a infecção por B. abortus está presente em equinos do município de Mossoró, Rio Grande do Norte.


The aims of the present study were (i) to determine the occurrence and (ii) to evaluate possible factors associated with infection by Brucella abortus in free-ranging equids from Mossoró, Rio Grande do Norte, Brazil. Sera from 227 free-ranging equids (178 donkeys, 43 horses and 6 mules), captured by the highway police and the prefecture agents, were screened by the rose bengal test (RBT) and confirmed for B. abortus-antibodies by the standard tube agglutination (STAT) and the 2-mercaptoethanol (2ME) tests. Of the 227 equids tested, four (1.76%) were positive for B. abortus antibodies. All were horses, which resulted in an observed frequency of infection for this species of 9.30% (4/43). No association was found among seropositivity for B. abortus and the age and sex. Thus, data from the present study showed that infection by B. abortus is present among horses in Mossoró, Rio Grande do Norte, Brazil.

6.
Semina Ci. agr. ; 34(6): 2951-2956, 2013.
Artigo em Inglês | VETINDEX | ID: vti-472390

RESUMO

The aim of this survey was to verify the occurrence of anti-Leptospira spp. antibodies in captive animals in the Parque Zoobotânico Arruda Câmara, João Pessoa, Paraíba State, Northeastern Brazil. Blood samples were collected from 49 animals: 26 mammals of the species Sapajus libidinosus, Cebus flavius, Saimiri sciureu, Coendu sp., Pseudalopex vetulus, Leopardus pardalis, Leopardus tigrinus, Galactitis vitata, Eira barbara, Nasua nasua, Tayassu tajacu and Ratus norvegicus; 10 birds of the species Penelope jacucaca, Pavo cristatus, Anodorhynchus hyacinthinus, Ara chlorothpterus, Pionites leucogaster, Polyborus plancus, Geranoaetus melanoleucus and Urubitinga urubitinga; and 13 reptiles of the species Caiman latirostris, Paleosuchus trigonatus, Caiman crocodilus, Tupinabis merinae, Tupinambis teguixin, Boa constrictor, Corallus hortulanus, Python molurus, Bufocephala vanderhaegei, Geochelone denticulata and Geochelone carboraria. Sera were examined by the microscopic agglutination teste (MAT) using 24 serovars as antigens and cut-off point of 1:100. One ocelot (Leopardo pardalis) presented positive reaction for the Icterohaemorrhagiae serovar with titer of 100, however, it did not show any clinical sign of the infection. Sinantropic rodents are the main reservoirs of this serovar, which suggests the need of maintenance and continuous evaluation of rodent control programs.


Canine brucellosis is an infectious disease of worldwide distribution that can affect dogs, wild canids and man. It is caused by Brucella canis, but dogs can also be infected by smooth Brucella such as B. abortus and B. suis. Due to the increasing importance of dogs in our society, to the scarcity of information about canine brucellosis in the country and its zoonotic character, the aims of the present study were (i) to conduct a survey on the infection by B. canis and smooth Brucella in dogs from the municipality of Araguaína, Tocantins, Brazil, and (ii) to evaluate the risk factors associated with these infections. Sera from 241 dogs were analyzed by agar gel immunodiffusion (AGID) to detect B. canisantibodies, and Buffered Acidified Plate Antigen test (BAPA) and fluorescence polarization assay (FPA) to detect antibodies to smooth Brucella. From the 241 tested dogs, 132 reacted in the AGID and 128 reacted in the BAPA, but only two were positive in FPA. The seroprevalences of B. canis and smooth Brucella infections in dogs in Araguaína were 54.77% (95% CI: 48.25 to 61.17%) and 0.83% (95% CI: 0.10 to 2.97%), respectively. The analysis of risk factors showed associations between B. canis infection and vaccination against leptospirosis, and between B. canis infection and use of manufactured food. In conclusion, data from the present study showed a low prevalence of infection by s

7.
Semina ciênc. agrar ; 34(3): 1281-1286, 2013.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1499223

RESUMO

Os objetivos deste trabalho foram (i) determinar a ocorrência da infecção por Brucella abortus em equídeos de vida livre no município de Mossoró, Rio Grande do Norte e (ii) avaliar possíveis fatores associados a esta infecção. Soros de 227 equídeos (178 asininos, 43 equinos e 6 muares), capturados pela polícia rodoviária e funcionários da prefeitura, foram coletados por punção venosa. A pesquisa de anticorpos anti-Brucella abortus foi realizada empregando-se, como triagem, o teste do antígeno acidificado tamponado (AAT) e como confirmatório o teste de redução pelo 2-Mercaptoetanol (2ME). Dos animais testados, quatro (1,76%) foram positivos para anticorpos anti- B. abortus. Todos os positivos eram equinos (9,30%, 4/43). A análise das variáveis levantadas (sexo e idade) como possíveis fatores associados à infecção por B. abortus não revelou a existência de associação entre estas e a soropositividade. Assim, o presente estudo permite concluir que a infecção por B. abortus está presente em equinos do município de Mossoró, Rio Grande do Norte.


The aims of the present study were (i) to determine the occurrence and (ii) to evaluate possible factors associated with infection by Brucella abortus in free-ranging equids from Mossoró, Rio Grande do Norte, Brazil. Sera from 227 free-ranging equids (178 donkeys, 43 horses and 6 mules), captured by the highway police and the prefecture agents, were screened by the rose bengal test (RBT) and confirmed for B. abortus-antibodies by the standard tube agglutination (STAT) and the 2-mercaptoethanol (2ME) tests. Of the 227 equids tested, four (1.76%) were positive for B. abortus antibodies. All were horses, which resulted in an observed frequency of infection for this species of 9.30% (4/43). No association was found among seropositivity for B. abortus and the age and sex. Thus, data from the present study showed that infection by B. abortus is present among horses in Mossoró, Rio Grande do Norte, Brazil.

8.
Semina ciênc. agrar ; 34(6): 2951-2956, 2013.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1499433

RESUMO

The aim of this survey was to verify the occurrence of anti-Leptospira spp. antibodies in captive animals in the Parque Zoobotânico Arruda Câmara, João Pessoa, Paraíba State, Northeastern Brazil. Blood samples were collected from 49 animals: 26 mammals of the species Sapajus libidinosus, Cebus flavius, Saimiri sciureu, Coendu sp., Pseudalopex vetulus, Leopardus pardalis, Leopardus tigrinus, Galactitis vitata, Eira barbara, Nasua nasua, Tayassu tajacu and Ratus norvegicus; 10 birds of the species Penelope jacucaca, Pavo cristatus, Anodorhynchus hyacinthinus, Ara chlorothpterus, Pionites leucogaster, Polyborus plancus, Geranoaetus melanoleucus and Urubitinga urubitinga; and 13 reptiles of the species Caiman latirostris, Paleosuchus trigonatus, Caiman crocodilus, Tupinabis merinae, Tupinambis teguixin, Boa constrictor, Corallus hortulanus, Python molurus, Bufocephala vanderhaegei, Geochelone denticulata and Geochelone carboraria. Sera were examined by the microscopic agglutination teste (MAT) using 24 serovars as antigens and cut-off point of 1:100. One ocelot (Leopardo pardalis) presented positive reaction for the Icterohaemorrhagiae serovar with titer of 100, however, it did not show any clinical sign of the infection. Sinantropic rodents are the main reservoirs of this serovar, which suggests the need of maintenance and continuous evaluation of rodent control programs.


Canine brucellosis is an infectious disease of worldwide distribution that can affect dogs, wild canids and man. It is caused by Brucella canis, but dogs can also be infected by smooth Brucella such as B. abortus and B. suis. Due to the increasing importance of dogs in our society, to the scarcity of information about canine brucellosis in the country and its zoonotic character, the aims of the present study were (i) to conduct a survey on the infection by B. canis and smooth Brucella in dogs from the municipality of Araguaína, Tocantins, Brazil, and (ii) to evaluate the risk factors associated with these infections. Sera from 241 dogs were analyzed by agar gel immunodiffusion (AGID) to detect B. canisantibodies, and Buffered Acidified Plate Antigen test (BAPA) and fluorescence polarization assay (FPA) to detect antibodies to smooth Brucella. From the 241 tested dogs, 132 reacted in the AGID and 128 reacted in the BAPA, but only two were positive in FPA. The seroprevalences of B. canis and smooth Brucella infections in dogs in Araguaína were 54.77% (95% CI: 48.25 to 61.17%) and 0.83% (95% CI: 0.10 to 2.97%), respectively. The analysis of risk factors showed associations between B. canis infection and vaccination against leptospirosis, and between B. canis infection and use of manufactured food. In conclusion, data from the present study showed a low prevalence of infection by s

9.
Semina Ci. agr. ; 33(4): 1521-1524, 2012.
Artigo em Português | VETINDEX | ID: vti-471300

RESUMO

O objetivo deste trabalho foi estimar a prevalência de anticorpos contra o vírus da língua azul (BTV) em rebanhos ovinos do Distrito Federal. Soros de 606 ovinos, pertencentes a 18 propriedades, foram analisados pela técnica de imunodifusão em ágar gel (AGID), para pesquisa de anticorpos contra o BTV. As prevalências de rebanhos e de animais infectados pelo vírus da língua azul no Distrito Federal foram respectivamente de 100% (IC 95%: 84,67% a 100%) e de 52,37% (389/606) (IC 95%: 35,76% a 68,98%). Assim, o presente estudo permite concluir que o vírus da língua azul está amplamente disseminada no rebanho ovino do Distrito Federal.


The aims of the present study were to determine the prevalence of bluetongue virus antibodies in sheep from Distrito Federal. Sera from 606 sheep of 18 herds were submitted to the agar-gel immunodiffusion for bluetongue virus antibodies. The prevalences of bluetongue infection found in Distrito Federal were 100% (CI 95%: 84.67 to 100.00) for flocks and 52.37% (389/606) (CI 95%: 35.76 to 68.98) for animals. Thus, data from the present study showed that infection by bluetongue virus is highly widespread in sheep flocks in the Distrito Federal, which intensifies the need for assessments on the impact of this disease in Brazil.

10.
Semina ciênc. agrar ; 33(4): 1521-1524, 2012.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1498896

RESUMO

O objetivo deste trabalho foi estimar a prevalência de anticorpos contra o vírus da língua azul (BTV) em rebanhos ovinos do Distrito Federal. Soros de 606 ovinos, pertencentes a 18 propriedades, foram analisados pela técnica de imunodifusão em ágar gel (AGID), para pesquisa de anticorpos contra o BTV. As prevalências de rebanhos e de animais infectados pelo vírus da língua azul no Distrito Federal foram respectivamente de 100% (IC 95%: 84,67% a 100%) e de 52,37% (389/606) (IC 95%: 35,76% a 68,98%). Assim, o presente estudo permite concluir que o vírus da língua azul está amplamente disseminada no rebanho ovino do Distrito Federal.


The aims of the present study were to determine the prevalence of bluetongue virus antibodies in sheep from Distrito Federal. Sera from 606 sheep of 18 herds were submitted to the agar-gel immunodiffusion for bluetongue virus antibodies. The prevalences of bluetongue infection found in Distrito Federal were 100% (CI 95%: 84.67 to 100.00) for flocks and 52.37% (389/606) (CI 95%: 35.76 to 68.98) for animals. Thus, data from the present study showed that infection by bluetongue virus is highly widespread in sheep flocks in the Distrito Federal, which intensifies the need for assessments on the impact of this disease in Brazil.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA