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1.
World J Microbiol Biotechnol ; 38(6): 103, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35501420

RESUMO

Infectious bovine keratoconjunctivitis (IBK) is an ocular disease affecting bovine herds worldwide, and it causes significant economic loss. The etiologic agent of IBK is considered to be Moraxella bovis, but M. ovis and M. bovoculi are frequently recovered of animals presenting clinical signs of IBK. The therapeutic measures available for its control have limited efficacy. Antimicrobial photodynamic therapy (aPDT) using porphyrins as photosensitizing molecules is an alternative method that can be used to reduce microbial growth. We evaluated the antibacterial activity of aPDT using two water-soluble tetra-cationic porphyrins (H2TMeP and ZnTMeP) against 22 clinical isolates and standard strains of Moraxella spp. in vitro and in an ex vivo model. For the in vitro assay, 4.0 µM of porphyrin was incubated with approximately 1.0 × 104 CFU/mL of each Moraxella sp. isolate and exposed to artificial light for 0, 2.5, 5, and 7.5 min. Next, 50 µL of this solution was plated and incubated for 24 h until CFU measurement. For the ex vivo assay, corneas excised from the eyeballs of slaughtered cattle were irrigated with Moraxella spp. culture, followed by the addition of zinc(II) porphyrin ZnTMeP (4.0 µM). The corneal samples were irradiated for 0, 7.5, and 30 min, followed by swab collection, plating, and CFU count. The results demonstrated the in vitro inactivation of the strains and clinical isolates of Moraxella spp. after 2.5 min of irradiation using ZnTMeP, reaching complete inactivation until 7.5 min. In the ex vivo experiment, the use of ZnTMeP resulted in the most significant reduction in bacterial concentration after 30 min of irradiation. These results encourage future in vivo experiments to investigate the role of metalloporphyrin ZnTMeP in the inactivation of Moraxella spp. isolates causing IBK.


Assuntos
Anti-Infecciosos , Doenças dos Bovinos , Ceratoconjuntivite Infecciosa , Ceratoconjuntivite , Infecções por Moraxellaceae , Fotoquimioterapia , Porfirinas , Animais , Antibacterianos/farmacologia , Bovinos , Doenças dos Bovinos/microbiologia , Ceratoconjuntivite Infecciosa/tratamento farmacológico , Ceratoconjuntivite Infecciosa/microbiologia , Moraxella , Infecções por Moraxellaceae/tratamento farmacológico , Infecções por Moraxellaceae/microbiologia , Infecções por Moraxellaceae/veterinária , Porfirinas/farmacologia , Ovinos
2.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1719-1726, Sept.-Oct. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131563

RESUMO

Neospora caninum is the main etiologic agent of neosporosis in domestic animals and its pathogenesis comprises two characteristic phases: acute and chronic. Rodents are used as experimental models to mimic acute and chronic bovine neosporosis. In this study, we inoculated a total of 27 female gerbils, with different doses of N. caninum tachyzoites aiming to induce chronic disease. DNA was extracted from different organs of each animal after spontaneous death or euthanasia. Encephalic tissues were submitted to a highly sensitive real time PCR aiming to detect chronically infected animals. All the other samples were submitted to standard PCR. A total of 11 gerbils died due to acute neosporosis, as confirmed by N. caninum DNA detection in organs. 5x103 tachyzoites/mL of N. caninum was the dosage of antigen that can induce chronic infection in gerbils. In the encephalon sections of some animals that showed clinical signs of persistent infection, we found 70% positive for the anterior encephalon section, suggesting this area as preferential for cyst formation. Therefore, we determined the doses of tachyzoites that cause acute or chronic infection and detection of positive tissues, preferably, systemic organs during acute and encephalon in chronic phases.(AU)


Neospora caninum é o principal agente etiológico da neosporose em animais domésticos, e sua patogênese compreende duas fases características: aguda e crônica. Roedores são usados como modelos experimentais para simular neosporose bovina aguda e crônica. Neste estudo, foi inoculado um total de 27 gerbilos, fêmeas, com diferentes doses de taquizoítos de N. caninum, visando induzir doença crônica. O DNA foi extraído de diferentes órgãos de cada animal após a morte espontânea ou a eutanásia. Os tecidos encefálicos foram submetidos à PCR em tempo real de alta sensibilidade para detecção de animais com infecção crônica. Todas as outras amostras foram submetidas à PCR padrão. Um total de 11 gerbilos morreu devido à neosporose aguda, como confirmado pela detecção de DNA de N. caninum nos órgãos. A dosagem de antígeno que pode induzir infecção crônica foi de 5x103 taquizoítos/mL de N. caninum. Em seções do encéfalo de alguns animais, que apresentaram sinais clínicos de infecção persistente, encontraram-se 70% de positividade para a seção do encéfalo anterior, sugerindo essa área como preferencial para a formação de cisto. Assim, foram determinadas,, em gerbilos, as dosagens de taquizoítos capazes de induzir infecção crônica ou aguda, bem como foram detectados tecidos positivos, preferencialmente, em órgãos sistêmicos, na fase aguda, e no encéfalo, na crônica.(AU)


Assuntos
Animais , Feminino , Encéfalo/diagnóstico por imagem , Gerbillinae/parasitologia , Coccidiose/veterinária , Neospora/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Trofozoítos
3.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1339-1345, July-Aug. 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131509

RESUMO

Free-range chickens may ingest oocysts of T. gondii present in the environment and consequently harbor virulent strains of this parasite in different tissues, without any clinical signs. Isolation of T. gondii through bioassays on mice and cats from naturally infected chicken tissues has been described in several countries, demonstrating the importance of free-range chickens in the transmission of this parasite. The aim of this study was the genotypic characterization of T. gondii isolates obtained from naturally infected free-range chickens in a rural area of the state of Rio Grande do Sul, Brazil. Brain and heart tissue from 12 chickens seropositive for T. gondii were processed using peptic digestion technique for parasite isolation. From 12 samples subjected to mouse bioassay, nine isolates were obtained. RFLP-PCR genotypic characterization was performed using 11 genetic markers: SAG1, 5'-3'SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. Genetic characterization of the isolates revealed the presence of five atypical genotypes according to ToxoDB (# 11, # 55, # 64, # 140 and # 163). Our results showed a wide genetic diversity of T. gondii in free-range chickens in this region.(AU)


Galinhas criadas ao ar livre podem ingerir oocistos de T. gondii presentes no ambiente e, com isso, albergar cepas virulentas desse parasita em diferentes tecidos, sem sinais clínicos. O isolamento de T. gondii por meio de bioensaios em camundongos e gatos, a partir de tecidos de galinhas naturalmente infectadas, tem sido descrito em vários países. Isso demonstra a importância das galinhas caipiras na epidemiologia desse parasita. O objetivo deste trabalho foi caracterizar genotipicamente isolados de T. gondii obtidos de galinhas caipiras naturalmente infectadas em uma área rural do município de Santa Maria, estado do Rio Grande do Sul, Brasil. Fragmentos de cérebro e de coração, de 12 galinhas soropositivas para T. gondii, foram processados pela técnica de digestão péptica para isolamento do parasita. Das 12 amostras submetidas a bioensaio com camundongos, nove isolados foram obtidos. A caracterização genotípica por RFLP-PCR foi realizada utilizando-se 11 marcadores genéticos: SAG1, 5'-3'SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 e Apico e revelou a presença de cinco genótipos atípicos de acordo com o ToxoDB (# 11, # 55, # 64, # 140 e # 163). Os resultados mostraram uma ampla diversidade genética de T. gondii em galinhas caipiras nessa região.(AU)


Assuntos
Animais , Camundongos , Toxoplasma , Bioensaio/veterinária , Galinhas/virologia , Toxoplasmose Animal , Técnicas de Genotipagem/veterinária , Zona Rural , Reação em Cadeia da Polimerase/veterinária
4.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 109-116, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888086

RESUMO

O objetivo do presente trabalho foi determinar a presença de anticorpos para Leishmania infantum, Neospora caninum e Toxoplasma gondii, por meio da reação de imunofluorescência indireta (RIFI), em cães (n=78) provenientes da região central do Rio Grande do Sul, necropsiados no Hospital Veterinário da Universidade Federal de Santa Maria (UFSM), bem como avaliar os dados epidemiológicos, sazonais e anátomo-histopatológicos. Do total de animais avaliados, 67,9% (53/78) apresentaram soropositividade para ao menos um agente. A ocorrência de anticorpos para L. infantum, N. caninum e T. gondii foi de 33,3 (26/78), 37,1 (29/78) e 43,5% (34/78), respectivamente. Detectaram-se monoinfecções em 9,4% (5/53) para L. infantum, 18,8% (10/53) para N. caninum e 20,7% (11/53) para T. gondii. As coinfecções foram observadas em 27/53 (50,9%) dos animais. As infecções ocorreram independentemente de idade, sexo, procedência ou raça (P>0,05). Não se verificaram lesões anatomo-histopatológicas relacionadas aos agentes pesquisados, caracterizando-os como animais assintomáticos. Os resultados confirmaram a exposição de cães a esses protozoários na região central do RS e, em especial, demonstraram a circulação do agente causador da leishmaniose em uma área considerada indene para a enfermidade.(AU)


The present paper is aimed to determine the presence of antibodies for Leishmania infantum, Neospora caninum and Toxoplasma gondii by indirect immunofluorescence (IIF) in dogs (n=78) from the central region in the state of Rio Grande do Sul necropsied in the Veterinary Hospital from Universidade Federal de Santa Maria (UFSM). The data was evaluated regarding epidemiological, anatomic, and histopathologic findings. Of the total animals evaluated, 67.9% (53/78) showed seropositivity for at least one agent. The occurrence of antibodies to L. infantum, N. caninum and T. gondii was 33.3% (26/78) 37.1% (29/78) and 43.5% (34/78), respectively. The mono infections were detected in 9.4% (5/53) of L. infantum, 18.8% (10/53) for N. caninum and 20.7% (11/53) T. gondii. The coinfections occurred in 50.9% (27/53) of animals. There were not anatomical and histopathological lesions regarding these surveyed agents, characterizing them as subclinical animals. The results confirmed the exposition of dogs to these protozoa in the central region of the RS, highlighting the circulation of the causer agent of leishmaniasis in an area considered harmless for the disease.(AU)


Assuntos
Animais , Cães , Toxoplasma/patogenicidade , Leishmania infantum/patogenicidade , Neospora/patogenicidade , Cães/virologia , Autopsia/veterinária
5.
Arq. bras. med. vet. zootec ; 68(2): 271-275, mar.-abr. 2016.
Artigo em Inglês | LILACS | ID: lil-779800

RESUMO

The aim of this study was to examine the intra-uterine exposure to Sarcocystis spp. antigens, determining the number of foals with detectable concentrations of antibodies against these agents in the serum, before colostrum ingestion and collect data about exposure of horses to the parasite. Serum samples were collected from 195 thoroughbred mares and their newborns in two farms from southern Brazil. Parasite specific antibody responses to Sarcocystis antigens were detected using the indirect immunofluorescent antibody test (IFAT) and immunoblot analysis. In 84.1% (159/189) of the pregnant mares and in 7.4% (14/189) of foals we detected antibodies anti-Sarcocystis spp. by IFAT. All samples seropositive from foals were also positive in their respective mares. Serum samples of seropositive foals by IFAT, showed no reactivity on the immunoblot, having as antigens S. neurona merozoites. In conclusion, the intra-uterine exposure to Sarcocystis spp. antigens in horses was demonstrated, with occurrence not only in mares, but also in their foals, before colostrum ingestion these occurrences were reduced.


O objetivo deste estudo foi avaliar a exposição intrauterina ao Sarcocystis spp., para determinar o número de potros que possuem concentrações detectáveis de anticorpos contra esses agentes no soro, antes da ingestão do colostro, por meio da coleta de dados sobre a exposição a esses protozoários nos equinos. Amostras de soro foram coletadas de 195 éguas puro-sangue e seus respectivos potros recém-nascidos, em duas fazendas localizadas na região Sul do Brasil. Os testes utilizados na detecção de anticorpos específicos para o Sarcocystis foram a reação de imunofluorescência indireta (RIFI) e análise por meio de immunoblot. Pela RIFI, em 84,1% (159/189) das éguas e em 7,4% (14/189) dos potros foram detectados anticorpos anti-Sarcocystis spp. Todas as amostras soropositivas dos potros também foram positivas para suas respectivas mães. As amostras de soro dos potros soropositivos na RIFI, não apresentaram reatividade no immunoblot, tendo como antígenos merozoítos de S. neurona. Em conclusão, foi demonstrada a exposição intrauterina de Sarcocystis spp. em equinos, com ocorrência em éguas, porém, em seus respectivos potros, antes da ingestão de colostro a ocorrência foi reduzida.


Assuntos
Animais , Anticorpos Antiprotozoários/análise , Cavalos/parasitologia , Diagnóstico Pré-Natal/veterinária , Sarcocystis/patogenicidade , Encefalomielite/veterinária , Immunoblotting , Immunoblotting/veterinária , Troca Materno-Fetal , Estudos Soroepidemiológicos
6.
Arq. bras. med. vet. zootec ; 67(5): 1465-1468, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1095988

RESUMO

Sarcocystis neurona is the primary agent for Equine Protozoal Myeloencephalitis (EPM), important neurological disease characterized by behavior or muscular changes, that impairs animal performance and husbandry. Sarcocystis cruzi is a pathogen related to myositis in cattle. Although related the life cycles of the parasites are distinct. S. neurona has opossums (Didelphis spp.) and S. cruzi, dogs as definitive hosts. However, S. neurona and S. cruzi may undergo cross-reactivity in serological tests, interfering on results of EPM ante-mortem diagnostic tests. In the present study, serology of 189 mares was performed by indirect immunofluorescence antibody test, using antigens of S. neurona and S. cruzi in order to assess the exposure degree of animals to antigens. Analyzing the results, it was observed that most of the animals (84.13%) reacted with at least one protozoal species and the number of animals which showed antibodies against S. cruzi was greater than S. neurona (80.42% and 33.86%, respectively) and a third of seropositive animals reacted to antigens of both species.(AU)


Assuntos
Animais , Anticorpos Antiprotozoários/análise , Apicomplexa , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Sarcocistose/epidemiologia , Encefalomielite/veterinária , Cavalos
7.
Vet Parasitol ; 199(3-4): 242-6, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24290901

RESUMO

Besnoitia besnoiti is a cyst-forming parasite that has been associated with economic losses in Africa and Europe. Besnoitiosis is considered as a re-emergent disease in the European continent. It is unknown whether cattle are exposed to B. besnoiti in the Americas, thus the aim of this study was to serologically investigate antibodies against B. besnoiti in a total of 2014 cattle serum samples from two states from Brazil. All samples were evaluated by IFAT and part of the positive sera was tested by Western blot (WB) using tachyzoites extracts under non-reducing condition. A total of 3.48% (70/2014) of the tested sera reacted positively by IFAT with titers of 200 (85.7%), 400 (10%) and 800 (4.3%). When 47 positive samples were assessed by WB a range of antigens from 7 to 206 kDa was recognized by the IFAT-positive sera. The results are suggestive of exposure of Brazilian cattle to B. besnoiti due to the titers (≥ 200) observed for some sera using IFAT. However, the antigens recognized by the IFAT-positive animals did not completely match with the WB patterns previously described by other working groups. It is possible that Brazilian cattle are exposed to B. besnoiti strains with different antigenic composition of those described in the European and African continent. Further studies are needed to confirm the presence of B. besnoiti or other Besnoitia species in Brazilian cattle.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Sarcocystidae/imunologia , Animais , Western Blotting , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/epidemiologia , Técnica Indireta de Fluorescência para Anticorpo , Estudos Soroepidemiológicos
8.
Parasitol Int ; 61(4): 550-3, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22580448

RESUMO

Several formulations of macrocyclic lactones (abamectin, ivermectin, moxidectin), including ivermectin combined with pyrantel (tetrahydropyrimidine) and ivermectin combined with praziquantel (pyrazinoisoquinolin derivative), were tested regarding their efficacy to control gastrointestinal nematodes of horses on a stud farm in southern Brazil. In addition, we tested a pharmaceutically produced generic paste containing ivermectin 4%. Similar formulations of avermectins had different efficacies measured by reduction of EPG. Levels of efficacy of the tested drugs varied against Strongylus edentatus, S. equinus and S. vulgaris. The generic paste (ivermectin 4%) was less effective than the conventional drugs.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças dos Cavalos/parasitologia , Infecções Equinas por Strongyloidea/tratamento farmacológico , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/química , Quimioterapia Combinada , Fezes/parasitologia , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Contagem de Ovos de Parasitas , Infecções Equinas por Strongyloidea/parasitologia
9.
Rev. bras. plantas med ; 14(4): 712-716, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-664025

RESUMO

O uso indiscriminado de produtos químicos no controle do carrapato bovino constitui a principal causa do gradativo aumento do número de cepas resistentes deste parasita às bases disponíveis no mercado. A utilização de óleos essenciais e extratos vegetais é uma prática antiga no controle de carrapatos, porém só recentemente tem recebido a devida atenção dos pesquisadores. O objetivo deste experimento foi avaliar a eficácia in vitro do óleo de capim limão (Cymbopogon citratus) sobre fêmeas ingurgitadas de Rhipicephalus (Boophilus) microplus através do exame de biocarrapaticidograma. Foram testadas seis diluições do óleo de C. citratus (1; 5; 10; 25; 50 e 100%) em uma população de carrapatos resistentes a amidínicos e piretróides sintéticos. A inibição de postura foi de 3; 23; 46; 66; 46 e 46%, a eclosão larval foi de 83; 58; 31; 0; 38 e 25% e a eficácia do tratamento foi de 32; 64; 83; 100; 88 e 82%, respectivamente. O óleo de C. citratus apresentou controle parcial do carrapato R. microplus in vitro, mesmo frente a populações resistentes a produtos químicos.


The indiscriminate use of chemical products to control the cattle tick is the main cause of the gradual increase in the number of strains of this parasite that are resistant to the bases currently available in the market. The use of essential oils and plant extracts is an ancient practice for tick control; however, only recently has it received due attention by researchers. The aim of this experiment was to evaluate the in vitro efficacy of lemongrass (Cymbopogon citratus) essential oil on engorged females of Rhipicephalus (Boophilus) microplus through immersion test. Six concentrations of Cymbopogon citratus oil (1; 5; 10; 25; 50 and 100%) were tested against a tick population resistant to synthetic formamidines and pyrethroids. The inhibition of egg-laying was 3; 23; 46; 66; 46 and 46%, the hatching was 83; 58; 31; 0; 38 and 25%, and the treatment efficacy was 32; 64; 83; 100; 88 and 82%, respectively. C. citratus oil showed partial control of the tick R. microplus in vitro, even against populations resistant to chemical products.


Assuntos
Óleos Voláteis/análise , Cymbopogon/efeitos adversos , Rhipicephalus , Plantas Medicinais , Medicamento Fitoterápico , Acaricidas/análise
10.
Arq. bras. med. vet. zootec ; 63(1): 258-261, Feb. 2011.
Artigo em Inglês | LILACS | ID: lil-582353

RESUMO

O objetivo deste estudo foi avaliar a frequência de detecção de anticorpos contra Neospora spp. em cavalos de carroça e em cavalos da raça Crioula. Para tal, 214 amostras de soro foram coletadas e analisadas pela técnica de imunofluorescência indireta, das quais 91 eram de cavalos de carroça e 123 de cavalos da raça Crioula, todas provenientes da região central do Rio Grande do Sul. As frequências de anticorpos detectadas foram: 15,9 por cento (34/214) na população total estudada, 15,4 por cento (14/91) nos cavalos de carroça e 16,3 por cento (20/123) nos cavalos da raça Crioula. Estes resultados sugerem que a infecção por Neospora spp. está presente igualmente nas duas populaç ões. Assim, devido à importância e ao padrão da patogênese da neosporose em equinos, Neospora spp. deve ser incluído no diagnóstico de problemas reprodutivos em éguas e em casos de problemas neurológicos em equinos.


Assuntos
Animais , Anticorpos/imunologia , Cavalos/classificação , Neospora/microbiologia , Doenças Parasitárias/parasitologia
11.
Arq. bras. med. vet. zootec ; 62(6): 1511-1513, dez. 2010.
Artigo em Português | LILACS | ID: lil-576056

RESUMO

Since November 2007 until May 2009, 1,778 serum samples of cattle from dairy herds of the Southwest of Paraná State, Brazil, were used for search of anti-Neospora caninum antibodies. The frequency of seropositive animals, assessed by IFAT, was 24.2 percent (431/1,178), showing a relatively high occurrence in the studied population. These results show that Neospora caninum is widely distributed in the dairy cattle in the Southwest of Paraná State. The presence of Neospora caninum in a herd is worrisome, since this protozoan is closely related with reproductive disorders and low milk production in cattle.


Assuntos
Animais , Feminino , Bovinos , Neospora/patogenicidade , Placenta/parasitologia , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Prevalência
12.
Arq. bras. med. vet. zootec ; 62(1): 211-213, Feb. 2010.
Artigo em Inglês | LILACS | ID: lil-543096

RESUMO

Investigou-se a ocorrência de Cryptosporidium spp. em equinos de tração, domiciliados na cidade de Santa Maria, RS. Foram coletadas amostras de fezes diretamente da ampola retal de 52 animais, machos e fêmeas, sem raça definida, na faixa etária do nascimento aos 20 anos de idade. Todos os animais estudados não apresentavam sinal clínico da parasitose. Dentre as amostras analisadas, 38,5 por cento (20/52)foram positivas para oocistos de Cryptosporidium spp. A ocorrência do parasito foi maior em animais jovens (75 por cento; 12/16). Conclui-se que há elevado número de animais assintomáticos eliminando oocistos, que contribuem com a contaminação ambiental e, sobretudo, submetem os carroceiros aos riscos da zoonose.


Assuntos
Animais , Masculino , Feminino , Criptosporidiose/epidemiologia , Cryptosporidium/isolamento & purificação , Fezes/parasitologia , Brasil/epidemiologia , Cryptosporidium/parasitologia , Equidae
13.
Braz J Med Biol Res ; 39(7): 935-44, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16862285

RESUMO

Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV) frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV) and an antigenically identical but cytopathic virus (cpBVDV) can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98%) to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.


Assuntos
Efeito Citopatogênico Viral/genética , Vírus da Diarreia Viral Bovina/genética , Duplicação Gênica , Genoma Viral/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Animais , Bovinos , Vírus da Diarreia Viral Bovina/isolamento & purificação , Rearranjo Gênico , Dados de Sequência Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Braz. j. med. biol. res ; 39(7): 935-944, July 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-431563

RESUMO

Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV) frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV) and an antigenically identical but cytopathic virus (cpBVDV) can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98 percent) to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.


Assuntos
Animais , Bovinos , Efeito Citopatogênico Viral/genética , Vírus da Diarreia Viral Bovina/genética , Duplicação Gênica , Genoma Viral/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Vírus da Diarreia Viral Bovina/isolamento & purificação , Rearranjo Gênico , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Viral/genética
15.
Braz. j. med. biol. res ; 39(3): 335-343, Mar. 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-421366

RESUMO

Bovine herpesvirus type 5 (BHV-5) is a major agent of meningoencephalitis in cattle and establishes latent infections mainly in sensory nerve ganglia. The distribution of latent BHV-5 DNA in the brain of rabbits prior to and after virus reactivation was studied using a nested PCR. Fifteen rabbits inoculated intranasally with BHV-5 were euthanized 60 days post-inoculation (group A, N = 8) or submitted to dexamethasone treatment (2.6 mg kg-1 day-1, im, for 5 days) and euthanized 60 days later (group B, N = 7) for tissue examination. Two groups of BHV-1-infected rabbits (C, N = 3 and D, N = 3) submitted to each treatment were used as controls. Viral DNA of group A rabbits was consistently detected in trigeminal ganglia (8/8), frequently in cerebellum (5/8), anterior cerebral cortex and pons-medulla (3/8) and occasionally in dorsolateral (2/8), ventrolateral and posterior cerebral cortices, midbrain and thalamus (1/8). Viral DNA of group B rabbits showed a broader distribution, being detected at higher frequency in ventrolateral (6/7) and posterior cerebral cortices (5/7), pons-medulla (6/7), thalamus (4/7), and midbrain (3/7). In contrast, rabbits inoculated with BHV-1 harbored viral DNA almost completely restricted to trigeminal ganglia and the distribution did not change post-reactivation. These results demonstrate that latency by BHV-5 is established in several areas of the rabbit's brain and that virus reactivation leads to a broader distribution of latent viral DNA. Spread of virus from trigeminal ganglia and other areas of the brain likely contributes to this dissemination and may contribute to the recrudescence of neurological disease frequently observed upon BHV-5 reactivation.


Assuntos
Animais , Bovinos , Feminino , Masculino , Coelhos , Encéfalo/virologia , Encefalite Viral/virologia , Infecções por Herpesviridae/virologia , /efeitos dos fármacos , Meningoencefalite/virologia , Ativação Viral/efeitos dos fármacos , Doença Aguda , Linhagem Celular , Modelos Animais de Doenças , Dexametasona/farmacologia , Glucocorticoides/farmacologia , /isolamento & purificação , /fisiologia , Latência Viral/efeitos dos fármacos
16.
Braz J Med Biol Res ; 39(3): 335-43, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16501813

RESUMO

Bovine herpesvirus type 5 (BHV-5) is a major agent of meningoencephalitis in cattle and establishes latent infections mainly in sensory nerve ganglia. The distribution of latent BHV-5 DNA in the brain of rabbits prior to and after virus reactivation was studied using a nested PCR. Fifteen rabbits inoculated intranasally with BHV-5 were euthanized 60 days post-inoculation (group A, N = 8) or submitted to dexamethasone treatment (2.6 mg kg(-1) day(-1), im, for 5 days) and euthanized 60 days later (group B, N = 7) for tissue examination. Two groups of BHV-1-infected rabbits (C, N = 3 and D, N = 3) submitted to each treatment were used as controls. Viral DNA of group A rabbits was consistently detected in trigeminal ganglia (8/8), frequently in cerebellum (5/8), anterior cerebral cortex and pons-medulla (3/8) and occasionally in dorsolateral (2/8), ventrolateral and posterior cerebral cortices, midbrain and thalamus (1/8). Viral DNA of group B rabbits showed a broader distribution, being detected at higher frequency in ventrolateral (6/7) and posterior cerebral cortices (5/7), pons-medulla (6/7), thalamus (4/7), and midbrain (3/7). In contrast, rabbits inoculated with BHV-1 harbored viral DNA almost completely restricted to trigeminal ganglia and the distribution did not change post-reactivation. These results demonstrate that latency by BHV-5 is established in several areas of the rabbit's brain and that virus reactivation leads to a broader distribution of latent viral DNA. Spread of virus from trigeminal ganglia and other areas of the brain likely contributes to this dissemination and may contribute to the recrudescence of neurological disease frequently observed upon BHV-5 reactivation.


Assuntos
Encéfalo/virologia , Encefalite Viral/virologia , Infecções por Herpesviridae/virologia , Herpesvirus Bovino 5/efeitos dos fármacos , Meningoencefalite/virologia , Ativação Viral/efeitos dos fármacos , Doença Aguda , Animais , Bovinos , Linhagem Celular , Dexametasona/farmacologia , Modelos Animais de Doenças , Feminino , Glucocorticoides/farmacologia , Herpesvirus Bovino 5/isolamento & purificação , Herpesvirus Bovino 5/fisiologia , Masculino , Coelhos , Latência Viral/efeitos dos fármacos
17.
Vet Microbiol ; 98(3-4): 185-96, 2004 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-15036527

RESUMO

Venereal infection of bulls with bovine herpesvirus type 1.2 (BHV-1.2) may result in acute balanoposthitis followed by the establishment of latent infection, presumably in dorsal root nerve ganglia. We herein report the characterization of the acute and latent infection of young bulls with a Brazilian BHV-1.2 isolate and the investigation of neural and non-neural sites in which viral DNA persists during latent infection, i.e. 110 days after inoculation and 50 days after experimental reactivation. Intrapreputial inoculation of BHV-1.2 isolate SV-56/90 (10(6.5)pfu per animal) resulted in severe balanoposthitis, characterized by redness of the penis and preputial mucosa, coalescent vesicles and fibrinous exsudate in all four infected bulls. Virus shedding was detected in preputial secretions and semen up to days 14 and 13 pi, respectively. Dexamethasone administration at day 60 pi led to reactivation of the infection in all animals, resulting in virus shedding in preputial secretions and/or in semen. At day 50 post-reactivation (pr), the animals were euthanized and regional tissues were collected for PCR and virus isolation. Viral DNA was consistently detected in the dorsal root ganglia of nerves genito-femoral (4/4) and obturator (4/4); frequently in the pudendal (3/4), sciatic (3/4) and rectal caudal nerve ganglia (2/3). In addition, viral DNA was detected in the pelvic sympathetic plexus of one bull and in regional lymph nodes (deep inguinal (2/4); sacral (1/4); medial iliac (1/4)) of two bulls. No infectious virus could be recovered from homogenates of DNA positive tissues, indicating the absence of actively replicating virus. These results demonstrate that BHV-1.2 DNA may persist in several sacral nerve ganglia and in regional lymph nodes as well during latent infection, i.e. 50 days after experimental reactivation. These findings may help in understanding the pathogenesis of acute and latent genital infection by BHV-1.2.


Assuntos
Balanite (Inflamação)/veterinária , Balanite (Inflamação)/virologia , Doenças dos Bovinos/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/crescimento & desenvolvimento , Animais , Brasil , Bovinos , DNA Viral/química , DNA Viral/genética , Dexametasona/farmacologia , Gânglios Espinais/virologia , Glucocorticoides/farmacologia , Infecções por Herpesviridae/patologia , Infecções por Herpesviridae/virologia , Herpesvirus Bovino 1/genética , Linfonodos/virologia , Masculino , Reação em Cadeia da Polimerase , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Proteínas Virais , Ativação Viral/fisiologia , Eliminação de Partículas Virais
18.
Clin Neuropathol ; 14(6): 322-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8605737

RESUMO

Alpers' syndrome is a progressive neurodegenerative disorder with liver disease that usually presents in the first few years of life. Only rarely have patients presented later in life with delayed onset of Alpers' syndrome. Herein we present a case of a 17-year-old male with a progressive 8-month course of severe headaches, multiple stroke-like episodes with visual deficits, and seizures that concluded with acute hemorrhagic pancreatitis. Neuropathological findings were characteristic for Alpers' syndrome: neurodegeneration and astrogliosis of the occipital cortices including the striate cortices, similar but less advanced changes in the parietal cortices, right Ammons horn sclerosis, degeneration of the posterior columns, and mild cerebellar Purkinje cell loss. Examination of the liver revealed extensive centrilobular hepatocyte necrosis. Skeletal muscle did not contain ragged red fibers, nor were there mitochondrial DNA point mutations characteristic for mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS).


Assuntos
Encéfalo/patologia , Transtornos Cerebrovasculares/patologia , Esclerose Cerebral Difusa de Schilder/patologia , Convulsões/patologia , Adolescente , Córtex Cerebral/patologia , Transtornos Cerebrovasculares/genética , DNA/genética , Diagnóstico Diferencial , Esclerose Cerebral Difusa de Schilder/genética , Humanos , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Degeneração Neural/fisiologia , Neurônios/patologia , Mutação Puntual/genética , Células de Purkinje/patologia , Convulsões/genética
19.
J Neurooncol ; 22(1): 55-65, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7714551

RESUMO

PURPOSE: A two-arm randomized clinical trial was performed to determine the efficacy of PCNU and AZQ in the treatment of de novo or recurrent primary brain tumors. An additional objective was to gather information on the administration and toxicity of these compounds, supplementing that obtained previously in phase I/II studies. METHODS: During 1982 and 1983 the Brain Tumor Study Group randomized 152 adult patients with primary brain tumors to receive PCNU 75-100 mg/m2 intravenously (IV) every 8 weeks or AZQ 15 mg/m2 IV once a week for 4 weeks, every 6-8 weeks. All patients who had not received 'full dose' radiotherapy before randomization received it concurrently with the first course of protocol chemotherapy. The data were analyzed for the total randomized population (RP), and for 130 patients in the valid study group (VSG) formed by excluding 22 patients for whom the histologic diagnosis was not documented by central review. RESULTS: Median survival times were 11.0 months for the PCNU group and 8.4 months for the AZQ group. The difference in survival curves was statistically significant for the RP (p = 0.01) and the VSG (p = 0.02). Life-table analysis of the VSG showed estimated 2-year survivals of 34% for PCNU and 11% for AZQ. The advantage of PCNU remained significant (p = 0.006) after adjustment for histopathologic category, age, initial performance status, and interval from initial reported surgery. Myelosuppression was the principal toxicity in both groups.


Assuntos
Antineoplásicos , Aziridinas/uso terapêutico , Benzoquinonas/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Compostos de Nitrosoureia/uso terapêutico , Aziridinas/efeitos adversos , Benzoquinonas/efeitos adversos , Criança , Humanos , Pessoa de Meia-Idade , Compostos de Nitrosoureia/efeitos adversos , Estudos Prospectivos , Recidiva , Análise de Sobrevida
20.
J Neurooncol ; 15(2): 181-4, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8509822

RESUMO

The objective of this trial was to determine the efficacy of echinomycin (1.2 mg/m2) administered on a weekly times four schedule in the treatment of patients with recurrent or progressive central nervous malignancies despite adequate radiotherapy. Thirty-five patients were registered on study. The majority of patients (20) had glioblastoma multiforme. Ten had anaplastic astrocytoma. Eight patients had received prior nitrosoureas. SWOG performance status was 1 in 11 patients and 2 in 22. The median age was 51 years (25-75 years). One patient had a partial remission (3%:95% confidence interval: 1%-16%). Twenty two patients had progressive disease. The median survival was 5.9 months. Toxicity was primarily gastrointestinal with nausea and vomiting in 13 patients and nausea only in 11 patients. Hepatotoxicity occurred in 10 patients. Echinomycin given at this dose and schedule is not effective in treating patients with recurrent or progressive glioblastoma multiforme or anaplastic astrocytomas.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Equinomicina/uso terapêutico , Glioma/tratamento farmacológico , Adulto , Idoso , Esquema de Medicação , Equinomicina/efeitos adversos , Feminino , Glioma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
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