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1.
Vector Borne Zoonotic Dis ; 24(2): 104-110, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37910779

RESUMO

Background: Although Brucella abortus, Brucella suis, and Brucella canis may infect humans and dogs worldwide, no study to date has assessed and compared owners and their dogs between island and mainland seashore areas. Materials and Methods: Accordingly, the study herein has applied serological tests, including Microplate Agglutination Test with 2-Mercaptoethanol, immunochromatographic assay, and Rose Bengal Test, and a Brucella genus-specific PCR assay to 195 owners and their 148 dogs living on 1 mainland seashore area and three nearby oceanic islands of southern Brazil. Results: No seropositivity to B. abortus and B. suis was detected in owner or dog sera. Anti-B. canis seropositivity was observed in 3/148 (2.0%) dogs, but no owner sample was seropositive to B. canis. In addition, all blood samples from both owners and dogs were negative on Brucella genus-specific PCR assay. Conclusions: The seropositive dogs were not related and lived on the seashore mainland area of Guaraqueçaba city. The absence of seropositivity on the islands and the low seropositivity on the seashore mainland could be attributed to geographic isolation, and suggest the low impact of the disease in the region. Despite being a zoonotic disease, brucellosis by B. canis is not included in the National Program for Control and Eradication of Brucellosis, and its diagnosis and notification are not mandatory. The presence of seropositive dogs highlights the risk to human health and the importance of epidemiological surveillance actions in the region, as well as the need for the implantation of preventive measures to avoid the transmission of the pathogen.


Assuntos
Brucella canis , Brucelose , Doenças do Cão , Humanos , Cães , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Brucelose/epidemiologia , Brucelose/veterinária , Brucelose/diagnóstico , Brucella canis/genética , Brucella abortus
2.
Pathogens ; 12(7)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37513720

RESUMO

The performance of a commercial immunofluorescence assay (IFA commercial), an in-house immunofluorescence assay (IFA in-house) and an indirect enzyme-linked immunosorbent assay (ELISA) were evaluated in the detection of antibodies anti-C. burnetii in the serum of Q fever patients and persons without the disease. For the study, seropositive and seronegative samples for Q fever (n = 200) from a serum bank of the Instituto Adolfo Lutz in Brazil were used. Commercial IFA was considered in this study as the gold standard for diagnosing Q fever. The in-house IFA demonstrated good agreement with the commercial test, showing high sensitivity (91%) and specificity (97%) compared to the gold standard, with a Kappa coefficient of 0.8954. The indirect ELISA test showed lower agreement with the gold standard, showing low sensitivity (67%), although the specificity of the technique was high (97%) and the Kappa coefficient was moderate (0.6631). In-house IFA is an excellent alternative for diagnosing Q fever.

3.
Braz J Microbiol ; 54(1): 449-457, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36571673

RESUMO

Central nervous system (CNS) infections comprise life-threatening clinical conditions in domestic species, and are commonly related to severe sequelae, disability, or high fatality rates. A set of bacterial pathogens have been identified in central nervous infections in livestock and companion animals, although the most of descriptions are restricted to case reports and a lack of comprehensive studies involving CNS-related bacterial infections have been focused on a great number of domestic species. In this scenario, we retrospectively investigated selected epidemiological data, clinical findings, bacteriological culture, and in vitro susceptibility patterns of 136 nonrepetitive neurologic cases in domestic species (2005-2021). Bacterial isolates were recovered from 25% (34/136) of the cerebrospinal fluid (CSF) sampled. The isolates were obtained from cattle (9/136 = 6.6%), dogs (7/136 = 5.1%), horses (6/136 = 4.4%), goats (3/136 = 2.2%), pigs (3/136 = 2.2%), sheep (3/136 = 2.2%), cats (2/136 = 1.5%), and asinine (1/136 = 0.7%). Among animals with bacterial isolation, Staphylococcus aureus (6/34 = 17.6%), Escherichia coli (5/34 = 14.7%), Staphylococcus beta-hemolytic (5/34 = 14.7%), and Trueperella pyogenes (3/34 = 8.8%) were predominant, in addition to a miscellaneous of other bacteria isolated in minor frequency, e.g., Corynebacterium pseudotuberculosis, Enterobacter cloacae, Mannheimia haemolytica, Pseudomonas aeruginosa, and Streptococcus equi subsp. equi. In vitro susceptibility tests of isolates revealed that amoxicillin/clavulanic acid (11/13 = 84.6%), cephalexin (9/11 = 81.8%), and florfenicol (9/12 = 75%) were the most effective antimicrobials. Conversely, isolates exhibited resistance mainly to tetracycline (6/10 = 60%), penicillin (6/11 = 54.5%), and trimethoprim/sulfamethoxazole (5/11 = 45.5%). Also, multidrug resistance to ≥ 3 classes of antimicrobials was found in 23.5% (8/34) strains. Data relative to the outcome was available in 79.4% (27/34) of animals that had bacterial isolation, and from these, the lethality rate was 92.6% (25/27). Incoordination (14/34 = 41.2%), recumbency (11/34 = 32.4%), apathy (10/34 = 29.4%), anorexia (9/34 = 26.5%), blindness (7/34 = 20.6%), seizure (6/34 = 17.6%), limb paresis (5/34 = 14.7%), head-pressing (4/34 = 11.8%), and nystagmus (3/34 = 8.8%) were the most frequent clinical signs. A variety of bacterial pathogens were identified in the CSF of domestic species showing neurologic signs, with a predominance of staphylococci, streptococci, and enterobacteria. High lethality of cases, poor in vitro efficacy of conventional antimicrobials, and a high in vitro multidrug resistance pattern of isolates were seen. Our results contribute to etiological characterization, antimicrobial resistance patterns, and clinical-epidemiological findings of bacterial infections in domestic species with neurological signs.


Assuntos
Farmacorresistência Bacteriana , Infecções Estafilocócicas , Animais , Cães , Bovinos , Cavalos , Suínos , Ovinos , Estudos Retrospectivos , Antibacterianos/farmacologia , Bactérias , Escherichia coli , Staphylococcus , Cabras , Testes de Sensibilidade Microbiana
4.
Viruses ; 14(4)2022 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-35458422

RESUMO

Pathogenicity and pathology of rabies virus (RABV) varies according to the variant, but the mechanisms are not completely known. In this study, gene expression profile in brains of mice experimentally infected with RABV isolated from a human case of dog rabies (V2) or vampire bat-acquired rabies (V3) were analyzed. In total, 138 array probes associated with 120 genes were expressed differentially between mice inoculated with V2 and sham-inoculated control mice at day 10 post-inoculation. A single probe corresponding to an unannotated gene was identified in V3 versus control mice. Gene ontology (GO) analysis revealed that all of the genes upregulated in mice inoculated with V2 RABV were involved in the biological process of immune defense against pathogens. Although both variants are considered pathogenic, inoculation by the same conditions generated different gene expression results, which is likely due to differences in pathogenesis between the dog and bat RABV variants. This study demonstrated the global gene expression in experimental infection due to V3 wild-type RABV, from the vampire bat Desmodus rotundus, an important source of infection for humans, domestic animals and wildlife in Latin America.


Assuntos
Quirópteros , Vírus da Raiva , Raiva , Animais , Cães , Camundongos , Análise em Microsséries , Transcriptoma , Virulência
5.
Front Vet Sci ; 8: 681423, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660750

RESUMO

The control of vampire bat rabies (VBR) in Brazil is based on the culling of Desmodus rotundus and the surveillance of outbreaks caused by D. rotundus in cattle and humans in addition to vaccination of susceptible livestock. The detection of anti-rabies antibodies in vampire bats indicates exposure to the rabies virus, and several studies have reported an increase of these antibodies following experimental infection. However, the dynamics of anti-rabies antibodies in natural populations of D. rotundus remains poorly understood. In this study, we took advantage of recent outbreaks of VBR among livestock in the Sao Paulo region of Brazil to test whether seroprevalence in D. rotundus reflects the incidence of rabies in nearby livestock populations. Sixty-four D. rotundus were captured during and after outbreaks from roost located in municipalities belonging to three regions with different incidences of rabies in herbivores. Sixteen seropositive bats were then kept in captivity for up to 120 days, and their antibodies and virus levels were quantified at different time points using the rapid fluorescent focus inhibition test (RFFIT). Antibody titers were associated with the occurrence of ongoing outbreak, with a higher proportion of bats showing titer >0.5 IU/ml in the region with a recent outbreak. However, low titers were still detected in bats from regions reporting the last outbreak of rabies at least 3 years prior to sampling. This study suggests that serological surveillance of rabies in vampire bats can be used as a tool to evaluate risk of outbreaks in at risk populations of cattle and human.

6.
J Food Prot ; 81(7): 1073-1078, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29897272

RESUMO

In Brazil, meat inspection occurs in a decentralized manner and consists of three types: (i) federal inspection (SIF), (ii) state inspection (SISP), and (iii) municipal inspection (SIM). The objective of this work was to discuss the three current inspection systems through the apparent prevalence of bovine brucellosis, a zoonosis that has an eradication program implemented by the Brazilian government. Nine abattoirs from federal, state, and municipal inspection systems were assessed and 1,490 animals were sampled. Serology for brucellosis was determined by the rose bengal test and the complement fixation test. The overall apparent prevalence (and 95% confidence interval) of brucellosis was 2.2% (1.5 to 2.9%). Apparent prevalence stratified by inspection system for SIF, SISP, and SIM was 0.4% (0.0 to 0.9%), 2.0% (0.8 to 3.2%), and 4.3% (2.5 to 6.1%), respectively. Multivariable logistic regression analysis revealed the odds ratio for finding an animal positive for brucellosis among inspection systems. A statistical difference ( P < 0.0015) was observed among surveillance systems, with SISP × SIF, SIM × SISP, and SIM × SIF having an odds ratio of 4,996, 2,304, and 11,494, respectively. Hence, the need for increasing official surveillance in state and municipal inspection systems seems to be necessary and could assist in the surveillance of bovine brucellosis and other diseases of interest to the federation. In addition, an increase in official presence would help to improve the selection of slaughtered cattle during ante- and postmortem inspection, with consequent impact on food safety and public health.


Assuntos
Matadouros , Brucelose , Animais , Brasil/epidemiologia , Brucelose/epidemiologia , Brucelose/veterinária , Bovinos , Inspeção de Alimentos/métodos , Humanos , Carne/microbiologia , Prevalência , Zoonoses/microbiologia , Zoonoses/prevenção & controle
7.
Viruses ; 10(2)2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29360742

RESUMO

The origin of Vaccinia virus (VACV) outbreaks in Brazil remains unknown, but since the isolation of VACV in Mus musculus mice during a zoonotic outbreak affecting cattle and milkers, peridomestic rodents have been suggested to be a link between cows and wild animals. Considering that experimentally infected mice eliminate viral particles in their feces, we investigated the presence of VACV in the feces and urine of wild rodents that were captured in the forest areas surrounding milking farms in the central west region of São Paulo State. For the first time, this work reports the detection of VACV by PCR in the feces of naturally infected Oligoryzomys flavescens, Oligoryzomys nigripes, and Sooretamys angouya, and in the urine of Oligorizomys flavescens, which raises important questions about the spread of VACV by rodent feces and its potential to induce clinical infections in cows.


Assuntos
Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais Selvagens , Roedores , Vírus Vaccinia , Vaccinia/veterinária , Eliminação de Partículas Virais , Doenças dos Animais/transmissão , Animais , Brasil/epidemiologia , Biologia Computacional/métodos , DNA Viral , Surtos de Doenças/veterinária , Fazendas , Fezes/virologia , Florestas , Geografia Médica , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Vírus Vaccinia/genética , Vírus Vaccinia/isolamento & purificação
8.
Viruses ; 10(1)2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346277

RESUMO

Outbreaks of Vaccinia virus (VACV) affecting cattle and humans have been reported in Brazil in the last 15 years, but the origin of outbreaks remains unknown. Although VACV DNA have been already detected in mice (Mus musculus), opossums (Didelphis albiventris) and dogs during VACV zoonotic outbreaks, no transmission to cattle or humans from any of these were reported during Brazilian outbreaks. In this work, we assessed the PCR positivity to VACV in blood samples of cows and other domestic mammals, wild rodents and other wild mammals, and humans from areas with or without VACV infection reports. Our results show the detection of VACV DNA in blood samples of cows, horse and opossums, raising important questions about VACV spread.


Assuntos
Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais Domésticos , Animais Selvagens , Vírus Vaccinia , Vaccinia/epidemiologia , Vaccinia/virologia , Carga Viral , Doenças dos Animais/transmissão , Animais , Brasil/epidemiologia , Surtos de Doenças , Fazendas , Genes Virais , Geografia Médica , Humanos , Filogenia , Vigilância em Saúde Pública , Vaccinia/transmissão , Vírus Vaccinia/classificação , Vírus Vaccinia/genética , Vírus Vaccinia/isolamento & purificação
9.
Pesqui. vet. bras ; 36(12): 1181-1185, Dec. 2016. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-842024

RESUMO

Since the first isolation of canine parvovirus type 2 (CPV-2) in late 70's new virus types as CPV-2a and CPV-2b have been emerged and becoming prevalent in natural canine population and more recently, a third subtype was identified , CPV-2c. The main purpose of this study was to detect and characterize canine parvovirus currently present in Central-West region of São Paulo state, in Brazil. Fecal samples were collected of vaccinated and non-vaccinated dogs, clinically suspected of having CPV infection brought to the Infectious Diseases Service, Veterinary Hospital of FMVZ-UNESP. All samples (n=30) were screening for canine parvovirus through hemagglutination test and those resulting as positive (n=20) were submitted to PCR and the products were subsequently sequenced for subtype characterization. Results were tested for association with age, hematological values, viral hemagglutination titers in the feces, vaccination status and survival. Leukopenia was found in all animals, death occurred in 30% of unvaccinated dogs and in 42% of vaccinated ones. In a total of 20 positive sequenced samples, 18 were classified as CPV-2b, one as CPV-2c, and one as CPV-2a, being CPV2a and CPV2c detected in unvaccinated puppies. Compared to the reference samples amino acid change at position 426 in those circling virus was identified. The study results demonstrate the predominance of CPV-2b and the presence of CPV-2a and CPV-2c in naturally infected, vaccinated and unvaccinated dogs in in São Paulo region.(AU)


Desde o primeiro isolamento do parvovirus canino tipo 2 (CPV-2) no final dos anos 70 novos subtipos virais como CPV-2a e CPV-2b surgiram e foram se tornando prevalentes na população canina; posteriormente um terceiro subtipo foi identificado, CPV- 2-C. O principal objetivo deste estudo foi detectar e caracterizar os subtipos de parvovírus canino atualmente presente na região Centro-Oeste do Estado de São Paulo-Brasil. Amostras de fezes foram coletadas de cães vacinados e não vacinados, atendidos no Serviço de Enfermidades Infecciosas dos Animais, Hospital Veterinário da FMVZ-UNESP, com suspeita clínica parvovirose . Todas as amostras (n = 30) foram submetidas teste de hemaglutinação para parvovirus canino e as positivas (n = 20) submetidas a PCR; os produtos amplificados foram subsequentemente sequenciados para caracterização do subtipo viral. Os resultados foram associados com a idade, os valores hematológicos, os títulos de hemaglutinação viral nas fezes, estado de vacinação e sobrevivência. A leucopenia foi encontrada em todos os animais; Obito foi observado em 30% dos cães não vacinados e 42% dos vacinados. Em um total de 20 amostras positivas sequenciadas, 18 foram classificadas como CPV-2b, uma como CPV-2c, e uma como CPV-2a. CPV 2a e CPV2c foram detectados em filhotes não vacinados. Em comparação com a amostra de referência foi evidenciada uma mudança de aminoácido na posição 426 nas amostras virais circulantes. Os resultados do estudo demonstram a predominância de CPV-2b e a presença de CPV-2a e CPV-2c em cães naturalmente infectados, vacinados e não vacinados na região de São Paulo.(AU)


Assuntos
Animais , Cães , Leucopenia/veterinária , Infecções por Parvoviridae/veterinária , Parvovirus Canino/isolamento & purificação , Testes de Hemaglutinação/veterinária , Reação em Cadeia da Polimerase/veterinária
10.
Ciênc. rural ; 46(5): 871-875, May 2016. tab
Artigo em Inglês | LILACS | ID: lil-777277

RESUMO

ABSTRACT: From May to September 2011, a total of 138 wild rodents of the Cricetidae family were collected in the cities of Anhembi, Bofete and Torre de Pedra, in São Paulo State. All animals were examined for the presence of ticks, which were collected and identified at species level in the laboratory by morphological examination (for adults, nymphs and larvae) and molecular biology, by sequencing of a fragment of the 16S mitochondrial rDNA (for larvae). A total of 47 ticks (21 larvae and 26 nymphs) were collected from rodents, identified as 21 larvae and 23 nymphs of Amblyomma ovale (collected on Oligoryzomys nigripes, Oligoryzomys flavescens, Sooretamys agouya and Nectomys squamipes), two nymphs of Ixodes schulzei (O. nigripes and O. flavescens) and an Amblyomma sculptum nymph in S. agouya. The overall prevalence of parasitism by A. ovale was 4.3% for larvae, and 10.1% for nymphs. The mean intensity of parasitism was 3.5 larvae/parasitized animal, and 1.6 nymphs/parasitized animal. One O. nigripes was found parasitized by both larva and nymph of A. ovale, and another O. nigripes was parasitized simultaneously by an I. schulzei nymph and five A. ovale nymphs. This research reports the following unpublished records: A. ovale on O. flavescens, O. nigripes and S. agouya; A. sculptum on S. agouya; and I. schulzei on O. flavescens and O. nigripes.


RESUMO: De maio a setembro de 2011, um total de 138 roedores silvestres da família Cricetidae foram coletados nos municípios de Anhembi, Bofete e Torre de Pedra, no estado de São Paulo. Todos os animais foram examinados quanto à presença de carrapatos, os quais foram coletados e identificados ao nível de espécie em laboratório, através de análises morfológicas (para adultos, ninfas e larvas) e por biologia molecular para confirmar estas análises, através do sequenciamento de um fragmento do gene 16S rDNA mitocondrial (para uma parte das larvas). Um total de 47 carrapatos (21 larvas e 26 ninfas) foi coletado dos roedores, sendo identificados como 21 larvas e 23 ninfas de Amblyomma ovale (coletados sobre Oligoryzomys nigripes, Oligoryzomys flavescens, Sooretamys agouya e Nectomys squamipes), duas ninfas de Ixodes schulzei (em O. nigripes e O. flavescens) e uma ninfa de Amblyomma sculptum em S. agouya. A prevalência geral de parasitismo por A. ovale foi de 4,3% e de 10,1% para larvas e ninfas, respectivamente. As intensidades médias de parasitismo foram de 3,5 larvas/animal parasitado e de 1,6 ninfas/animal parasitado. Um O. nigripes foi encontrado parasitado simultaneamente por larva e ninfa de A. ovale, e outro O. nigripes estava parasitado simultaneamente por uma ninfa de I. schulzei e cinco ninfas de A. ovale. O presente trabalho reporta os seguintes registros inéditos: A. ovale em O. flavescens, O. nigripes e S. agouya; A. sculptum em S. agouya; e I. schulzei em O. flavescens e O. nigripes.

11.
Emerg Infect Dis ; 22(2): 271-3, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26812352

RESUMO

During a vaccinia virus (VACV) outbreak in São Paulo State, Brazil, blood samples were collected from cows, humans, other domestic animals, and wild mammals. Samples from 3 dogs and 3 opossums were positive for VACV by PCR. Results of gene sequencing yielded major questions regarding other mammalian species acting as reservoirs of VACV.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Surtos de Doenças , Vírus Vaccinia/genética , Vaccinia/epidemiologia , Vaccinia/virologia , Animais , Brasil/epidemiologia , Bovinos , Cães , Genes Virais , Humanos , Gambás , Filogenia , Vaccinia/diagnóstico , Vírus Vaccinia/classificação
12.
Am J Trop Med Hyg ; 94(2): 378-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26711511

RESUMO

Rabies is a lethal infectious disease that causes 55,000 human deaths per year and is transmitted by various mammalian species, such as dogs and bats. The host immune response is essential for avoiding viral progression and promoting viral clearance. Cytokines and chemokines are crucial in the development of an immediate antiviral response; the rabies virus (RABV) attempts to evade this immune response. The virus's capacity for evasion is correlated with its pathogenicity and the host's inflammatory response, with highly pathogenic strains being the most efficient at hijacking the host's defense mechanisms and thereby decreasing inflammation. The purpose of this study was to evaluate the expression of a set of cytokine and chemokine genes that are related to the immune response in the brains of mice inoculated intramuscularly or intracerebrally with two wild-type strains of RABV, one from dog and the other from vampire bat. The results demonstrated that the gene expression profile is intrinsic to the specific rabies variant. The prompt production of cytokines and chemokines seems to be more important than their levels of expression for surviving a rabies infection.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica/imunologia , Vírus da Raiva/imunologia , Raiva/imunologia , Raiva/virologia , Animais , Citocinas/genética , Feminino , Camundongos , Camundongos Endogâmicos C57BL , RNA/genética , RNA/metabolismo , Organismos Livres de Patógenos Específicos , Transcriptoma
13.
Braz. j. infect. dis ; 19(5): 453-458, tab, graf
Artigo em Inglês | LILACS | ID: lil-764500

RESUMO

ABSTRACTWe have evaluated the efficacy of short-interfering RNAs targeting the nucleoprotein gene and also the brain immune response in treated and non-treated infected mice. Mice were inoculated with wild-type virus, classified as dog (hv2) or vampire bat (hv3) variants and both groups were treated or leaved as controls. No difference was observed in the lethality rate between treated and non-treated groups, although clinical evaluation of hv2 infected mice showed differences in the severity of clinical disease (p = 0.0006). Evaluation of brain immune response 5 days post-inoculation in treated hv2 group showed no difference among the analyzed genes, whereas after 10 days post-inoculation there was increased expression of 2',5'-oligoadenylate synthetase 1, tumor necrosis factor alpha, interleukin 12, interferon gamma, and C-X-C motif chemokine 10 associated with higher expression of Ngene in the same period (p < 0.0001). In hv2 non-treated group only higher interferon beta expression was found at day 5. The observed differences in results of the immune response genes between treated and non-treated groups is not promising as they had neither impact on mortality nor even a reduction in the expression of N gene in siRNA treated animals. This finding suggests that the use of pre-designed siRNA alone may not be useful in rabies treatment.


Assuntos
Animais , Cães , Feminino , Humanos , Camundongos , Antivirais/administração & dosagem , Quirópteros/virologia , RNA Interferente Pequeno/administração & dosagem , Vírus da Raiva/efeitos dos fármacos , Raiva/terapia , Encéfalo/imunologia , Linhagem Celular , Modelos Animais de Doenças , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus da Raiva/imunologia , Raiva/virologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
14.
Braz. j. infect. dis ; 19(5): 479-485, tab
Artigo em Inglês | LILACS | ID: lil-764507

RESUMO

ABSTRACTRabies virus (RABV) isolated from different mammals seems to have unique characteristics that influence the outcome of infection. RABV circulates in nature and is maintained by reservoirs that are responsible for the persistence of the disease for almost 4000 years. Considering the different pattern of pathogenicity of RABV strains in naturally and experimentally infected animals, the aim of this study was to analyze the characteristics of RABV variants isolated from the main Brazilian reservoirs, being related to a dog (variant 2),Desmodus rotundus (variant 3), crab eating fox, marmoset, and Myotis spp. Viral replication in brain tissue of experimentally infected mouse was evaluated by two laboratory techniques and the results were compared to clinical evolution from five RABV variants. The presence of the RABV was investigated in brain samples by fluorescent antibody test (FAT) and real time polymerase chain reaction (qRT-PCR) for quantification of rabies virus nucleoprotein gene (N gene). Virus replication is not correlated with clinical signs and evolution. The pattern of FAT is associated with RABV replication levels. Virus isolates from crab eating fox and marmoset had a longer evolution period and higher survival rate suggesting that the evolution period may contribute to the outcome. RABV virus variants had independent characteristics that determine the clinical evolution and survival of the infected mice.


Assuntos
Animais , Camundongos , Callithrix/virologia , Quirópteros/virologia , Cães/virologia , RNA Viral/genética , Vírus da Raiva/genética , Roedores/virologia , Replicação Viral/genética , Brasil , Reservatórios de Doenças/virologia , Imunofluorescência , Raposas/virologia , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/fisiologia
15.
Braz J Infect Dis ; 19(5): 453-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26254692

RESUMO

We have evaluated the efficacy of short-interfering RNAs targeting the nucleoprotein gene and also the brain immune response in treated and non-treated infected mice. Mice were inoculated with wild-type virus, classified as dog (hv2) or vampire bat (hv3) variants and both groups were treated or left as controls. No difference was observed in the lethality rate between treated and non-treated groups, although clinical evaluation of hv2 infected mice showed differences in the severity of clinical disease (p=0.0006). Evaluation of brain immune response 5 days post-inoculation in treated hv2 group showed no difference among the analyzed genes, whereas after 10 days post-inoculation there was increased expression of 2',5'-oligoadenylate synthetase 1, tumor necrosis factor alpha, interleukin 12, interferon gamma, and C-X-C motif chemokine 10 associated with higher expression of N gene in the same period (p<0.0001). In hv2 non-treated group only higher interferon beta expression was found at day 5. The observed differences in results of the immune response genes between treated and non-treated groups is not promising as they had neither impact on mortality nor even a reduction in the expression of N gene in siRNA treated animals. This finding suggests that the use of pre-designed siRNA alone may not be useful in rabies treatment.


Assuntos
Antivirais/administração & dosagem , Quirópteros/virologia , RNA Interferente Pequeno/administração & dosagem , Vírus da Raiva/efeitos dos fármacos , Raiva/terapia , Animais , Encéfalo/imunologia , Linhagem Celular , Modelos Animais de Doenças , Cães , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Raiva/virologia , Vírus da Raiva/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
16.
Braz J Infect Dis ; 19(5): 479-85, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26303004

RESUMO

Rabies virus (RABV) isolated from different mammals seems to have unique characteristics that influence the outcome of infection. RABV circulates in nature and is maintained by reservoirs that are responsible for the persistence of the disease for almost 4000 years. Considering the different pattern of pathogenicity of RABV strains in naturally and experimentally infected animals, the aim of this study was to analyze the characteristics of RABV variants isolated from the main Brazilian reservoirs, being related to a dog (variant 2), Desmodus rotundus (variant 3), crab eating fox, marmoset, and Myotis spp. Viral replication in brain tissue of experimentally infected mouse was evaluated by two laboratory techniques and the results were compared to clinical evolution from five RABV variants. The presence of the RABV was investigated in brain samples by fluorescent antibody test (FAT) and real time polymerase chain reaction (qRT-PCR) for quantification of rabies virus nucleoprotein gene (N gene). Virus replication is not correlated with clinical signs and evolution. The pattern of FAT is associated with RABV replication levels. Virus isolates from crab eating fox and marmoset had a longer evolution period and higher survival rate suggesting that the evolution period may contribute to the outcome. RABV virus variants had independent characteristics that determine the clinical evolution and survival of the infected mice.


Assuntos
Callithrix/virologia , Quirópteros/virologia , Cães/virologia , RNA Viral/genética , Vírus da Raiva/genética , Roedores/virologia , Replicação Viral/genética , Animais , Brasil , Reservatórios de Doenças/virologia , Imunofluorescência , Raposas/virologia , Camundongos , Filogenia , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/fisiologia , Reação em Cadeia da Polimerase em Tempo Real
17.
Biomed Res Int ; 2015: 981230, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090469

RESUMO

This paper describes the control, epidemiological, pathological, and molecular aspects of an outbreak of meningoencephalitis in calves due to bovine herpesvirus 5 at a feedlot with 540 animals in São Paulo State, Brazil. The introduction of new animals and contact between the resident animals and the introduced ones were most likely responsible for virus transmission. Bovine herpesvirus 1 vaccine was used, resulting in the efficacy of the outbreak control, although two bovine herpesvirus 1 positive animals, vaccinated and revaccinated, presented meningoencephalitis, thereby characterizing vaccinal failure.


Assuntos
Doenças dos Bovinos/epidemiologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Bovino 5/imunologia , Vacinas Virais/administração & dosagem , Agricultura , Animais , Anticorpos Antivirais/imunologia , Brasil , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/patologia , Surtos de Doenças , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/patologia , Herpesvirus Bovino 1/imunologia , Herpesvirus Bovino 1/patogenicidade , Herpesvirus Bovino 5/patogenicidade , Vacinas Virais/imunologia
18.
J Neurovirol ; 21(4): 370-82, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25698500

RESUMO

Our previous studies in an experimental model of rabies showed neuronal process degeneration in association with severe clinical disease. Cultured adult rodent dorsal root ganglion neurons infected with challenge virus standard (CVS)-11 strain of rabies virus (RABV) showed axonal swellings and reduced axonal growth with evidence of oxidative stress. We have shown that CVS infection alters a variety of mitochondrial parameters and increases reactive oxygen species (ROS) production and mitochondrial Complex I activity vs. mock infection. We have hypothesized that a RABV protein targets mitochondria and triggers dysfunction. Mitochondrial extracts of mouse neuroblastoma cells were analyzed with a proteomics approach. We have identified peptides belonging to the RABV nucleocapsid protein (N), phosphoprotein (P), and glycoprotein (G), and our data indicate that the extract was most highly enriched with P. P was also detected by immunoblotting in RABV-infected purified mitochondrial extracts and also in Complex I immunoprecipitates from the extracts but not in mock-infected extracts. A plasmid expressing P in cells increased Complex I activity and increased ROS generation, whereas expression of other RABV proteins did not. We have analyzed recombinant plasmids encoding various P gene segments. Expression of a peptide from amino acid 139-172 increased Complex I activity and ROS generation similar to expression of the entire P protein, whereas peptides that did not contain this region did not increase Complex I activity or induce ROS generation. These results indicate that a region of the RABV P interacts with Complex I in mitochondria causing mitochondrial dysfunction, increased generation of ROS, and oxidative stress.


Assuntos
Complexo I de Transporte de Elétrons/metabolismo , Fosfoproteínas/metabolismo , Vírus da Raiva/fisiologia , Raiva/virologia , Proteínas Virais/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Células HEK293 , Humanos , Imuno-Histoquímica , Imunoprecipitação , Camundongos , Mitocôndrias , Mutagênese Sítio-Dirigida , Estresse Oxidativo , Proteômica , Raiva/metabolismo , Transfecção
19.
Antivir Ther ; 20(1): 1-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25156675

RESUMO

Human rabies is virtually always fatal despite numerous attempts at aggressive therapy. Most survivors received one or more doses of rabies vaccine prior to the onset of the disease. The Milwaukee Protocol has proved to be ineffective for rabies and should no longer be used. New approaches are needed and an improved understanding of basic mechanisms responsible for the clinical disease in rabies may prove to be useful for the development of novel therapeutic approaches. Antiviral therapy is thought to be an important component of combination therapy for the management of human rabies, and immunotherapy and neuroprotective therapy should also be strongly considered. There are many important issues for consideration regarding drug delivery to the central nervous system in rabies, which are in part related to the presence of the blood-brain barrier and also the blood-spinal cord barrier. Ribavirin and interferon-α have proved to be disappointing agents for the therapy of rabies. There is insufficient evidence to support the continued use of ketamine or amantadine for the therapy of rabies. Minocycline or corticosteroids should not be used because of concerns about aggravating the disease. A variety of new antiviral agents are under development and evaluation, including favipiravir, RNA interference (for example, small interfering [si]RNAs) and novel targeted approaches, including interference with viral capsid assembly and viral egress.


Assuntos
Antivirais/uso terapêutico , Sistema Nervoso Central/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Vírus da Raiva/efeitos dos fármacos , Raiva/tratamento farmacológico , Corticosteroides , Amidas/uso terapêutico , Animais , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/virologia , Terapia Combinada , Contraindicações , Humanos , Minociclina , Terapia de Alvo Molecular , Pirazinas/uso terapêutico , RNA Interferente Pequeno/uso terapêutico , Raiva/imunologia , Raiva/patologia , Raiva/virologia , Vírus da Raiva/genética , Vírus da Raiva/patogenicidade , Montagem de Vírus/efeitos dos fármacos , Liberação de Vírus/efeitos dos fármacos
20.
Arq. Inst. Biol ; 82: 1-5, 2015. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1026318

RESUMO

A brucelose é uma importante zoonose causada por bactérias do gênero Brucella. O homem é infectado pelo contato com as secreções reprodutivas como placenta, lóquios placentários, sêmen e secreções penianas de animais infectados ou pelo consumo de leite e derivados não pasteurizados. Com o objetivo de pesquisar a presença da bactéria no leite, foram avaliadas, através da técnica da reação em cadeia da polimerase (PCR), 30 amostras de leite cru comercializadas clandestinamente na região de Botucatu, São Paulo, bem como 50 amostras de leite entregues em laticínio, previamente à pasteurização. Das 80 amostras analisadas pela técnica de PCR, 10 (12,5%) foram positivas e 70 (87,5%) negativas. Dentre as amostras positivas, 5 amostras (16,6%) eram provenientes de comerciantes ilegais e outras 5 amostras (10%) foram obtidas no laticínio. A positividade para Brucella spp. demonstra que o patógeno se encontra presente de forma importante na região de Botucatu, São Paulo, e que o risco associado à saúde pública devido à comercialização de produtos clandestinos sem prévia pasteurização é real.(AU)


Brucellosis is a zoonosis caused by bacteria of the genus Brucella. Man infection occurs through contact with reproductive secretions as placenta and its lochia, semen and penile secretion of infected animals or by consuming unpasteurized milk and dairy products. With the objective of investigating the presence of bacteria in milk, 30 samples of raw milk sold illegally in the region of Botucatu, São Paulo, Brazil, as well as 50 samples of milk delivered to a dairy industry previously to its pasteurization were evaluated by the polymerase chain reaction (PCR) technique. Of the 80 samples analyzed, 10 samples (12.5%) were positive and 70 (87.5%) were negative. Among the positive samples, 5 (16.6%) were from illegal traders and other 5 (10%) were obtained from the dairy industry. Brucella spp. positivity shows that the pathogen is representatively present in Botucatu, São Paulo, Brazil, and the risk associated to public health due to the commercialization of illegal products without pasteurization is real.(AU)


Assuntos
Humanos , Animais , Brucella abortus , Brucelose Bovina , Reação em Cadeia da Polimerase/veterinária , Leite , Pasteurização , Zoonoses , Comércio , Agroindústria
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