Molecular detection of hemoplasma infection among cats from São Luís island, Maranhão, Brazil

Hemoplasmas are bacteria that infect erythrocytes, attaching to the red blood cell. There is a need for more reports of hemoplasma infection prevalence and molecular characterization among cats in Brazil since there are only few published reports. The present work aimed to detect and molecularly characterize the presence of hemotrophic mycoplasmas in domestic cats with outdoor access from São Luís, Maranhão, Brazil. Twenty cats (10%) were positive for Candidatus M. haemominutum, five (2.5%) for M. haemofelis, and four (2.%) for M. turicensis based on 16S rRNA gene PCRs. Five cats (2.5%) were co-positive for Candidatus M. haemominutum and M. haemofelis. PCR diagnosis was confirmed by sequencing; and phylogenetic analysis was based on 16S rRNA and rnpb genes.

Proteinogramas séricos de ratos Wistar experimentalmente infectados com Trypanosoma evansi / Serum protein concentrations in Wistar rats experimentally infected with Trypanosoma evansi

Estabeleceu-se o perfil eletroforético de proteínas séricas de ratos Wistar experimentalmente infectados com Tripanosoma evansi, utilizando-se 40 ratos, distribuídos em oito grupos de cinco animais cada. Um grupo foi mantido como testemunho (G1), e os demais (G2 a G8) foram inoculados, via intraperitoneal, com cerca de 10³tripomastigota de T. evansi. Amostras de sangue para obtenção de soro foram coletadas no quinto (G2), 10º (G3), 15º (G4), 30º (G5), 45º (G6), 60º (G7) e 75º (G1 e G8) dia após as inoculações. O fracionamento das proteínas foi realizado pela técnica SDS-PAGE. Foram identificadas 31 proteínas, sendo sete de fase aguda: ceruloplasmina (101KD), hemopexina (83KD), transferrina (75KD), albumina (66KD), antitripsina (60KD), haptoglobina (44KD) e glicoproteína ácida (38KD). As proteínas com pesos moleculares 12KD; 22KD; 25KD; 28KD; 32,5KD; 35KD; 53,5KD; 63KD e 72KD apareceram apenas nos ratos inoculados com T. evansi.

This study established the electrophoretic profile of serum proteins of Wistar rats experimentally infected with Tripanosoma evansi. For such, 40 rats were allocated into eight groups of five animals. A group was kept as control (G1) and the others (G2 to G8) were intraperitoneally inoculated with 1.0 x 10³ tripomastigote of T. evansi. Blood samples were collected at 5th (G2), 10th (G3), 15th (G4), 30th (G5), 45th (G6), 60th (G7), and 75th (G1 and G8) days after inoculation (DAI). The serum protein concentrations were determined by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Thirty-one distinct proteins were identified, seven of these were identified as acute phase proteins: ceruloplasmin (110KD), hemopexin (83KD), transferrin (75KD), albumin (66KD), antitrypsin (60KD), haptoglobin (44KD), and acid glycoprotein (38KD). The proteins with molecular weights 12KD; 22KD; 25KD; 28KD; 32,5KD; 35KD; 53,5KD; 63KD, and 72KD were found only in infected rats.

In vitro culture, PCR, and nested PCR for the detection of Theileria equi in horses submitted to exercise / Cultivo in vitro, PCR e nested PCR na detecção de Theileria equi em eqüinos submetidos a exercícios

This study compared the usefulness of in vitro culture, PCR, and nested PCR for the diagnosis of Theileria equi in horses submitted to stress during exercise. Blood samples from 15 apparently healthy horses, previously conditioned to a high-speed equine treadmill, were taken prior to and after exercise. The animals were divided into two experimental groups: 30-day training schedule (G1) and 90-day training schedule (G2). Statistical analysis was performed using a chi-square test and kappa statistic was used in order to assess agreement. No significant difference was observed between samples collected at resting or after exercise. In G1, merozoites of T. equi were detected in the blood smears of four horses before in vitro culture, whereas 14 samples were positive, confirmed by culture. In G2, five and 11 horses were positive before and after culture, respectively. No PCR amplified product was observed in any of the tested animals although the PCR system based on the 16S rRNA gene of T. equi detected DNA in blood with an equivalent 8x10-5 percent parasitaemia. The nested PCR based on the T. equi merozoite antigen gene (EMA-1) allowed the visualization of amplified products in all the horses. Therefore, nested PCR should be considered as a means of detection of sub-clinical T. equi infections and in vitro culture could be used as a complement to other methods of diagnosis.

Comparou-se a utilização do cultivo in vitro, PCR e nested PCR no diagnóstico de Theileria equi em eqüinos submetidos ao estresse induzido por exercícios. Amostras de sangue foram obtidas de 15 eqüinos submetidos a treinamento em esteira rolante de alto desempenho, sendo as amostras colhidas antes e após os exercícios. Os animais foram divididos em dois grupos experimentais: 30 dias de treinamento (G1) e 90 dias de treinamento (G2). O teste do qui-quadrado foi empregado para as análises estatísticas e o índice kappa utilizado para avaliar a concordância. Não houve diferença significativa entre as amostras obtidas em repouso e após exercícios. Merozoítas de T. equi foram detectados em apenas quatro eqüinos do G1 pela microscopia direta realizada antes do cultivo, enquanto 14 animais apresentaram-se positivos pelo cultivo in vitro. No G2, cinco e 11 eqüinos foram positivos antes e após o cultivo, respectivamente. Nenhum produto de amplificação foi observado pela técnica de PCR, apesar do PCR baseado no gene 16S rRNA de T. equi ter detectado DNA em sangue com parasitemia equivalente a 8x10-5 por cento. O nested PCR, baseado na seqüência do gene do antígeno de merozoíta de T. equi (EMA-1,) permitiu a visualização de produtos de amplificação em todos os eqüinos testados. O nested PCR deve ser considerado para a detecção de infecções subclínicas de T. equi e o cultivo in vitro pode ser utilizado como uma ferramenta complementar a outros métodos de diagnóstico.

Toxoplasma gondii: cloning, sequencing, expression, and antigenic characterization of ROP2, GRA5 and GRA7

Toxoplasma gondii is an intracellular obligate protozoan, which infects humans and warm-blooded animals. The aim of the present study was to clone the rop2, gra5 and gra7 genes from T. gondii RH strain and to produce recombinant proteins. The rop2, gra5 and gra7 gene fragments produced by polymerase chain reaction were cloned into the pET102/D-TOPO® vector which contains thioredoxin and polyhistidine tags at the C- and N-ends, respectively, and is expressed in Escherichia coli BL21(DE-3). The expression fusion proteins were found almost entirely in the insoluble form in the cell lysate. These recombinant proteins were purified with an Ni-NTA column. Concentrations of the recombinant antigens produced in the E. coli BL21-star ranged from 300 to 500 μg/ml growth media, which was used to immunize rabbits. We observed an identity ranging from 96 to 97% when nucleotide sequences were compared to GenBank database sequences. Immunocharacterization of proteins was made by indirect immunofluorescence assay. These proteins will be used for serodiagnosis and vaccination.

Experimental Trypanosoma evansi infection in donkeys: hematological, biochemical and histopathological changes

Five adult donkeys were experimentally infected with Brazilian strain of Trypanosoma evansi originally isolated from a naturally infected dog to study the hematological biochemical and histopathological alterations during the evolution of the disease. The course of the experimental infection was followed up to 145 days. Hematological analyses of the infected donkeys revealed a marked decline in hemoglobin, packed-cell volume, and erythrocyte count. Anemia was observed after successive peaks of parasitemia. Biochemical analyses showed increased levels of icterus index, serum globulins and decreased serum albumin and glucose values. All infected donkeys revealed enlargement of spleen and its white pulp, enlargement of mediastinal lymph nodes and lungs congestion. The main histopathological features consisted of meningoencephalitis. Demyelination in some areas of the cerebellum pediculus and neuropil vacuolization were observed. This study showed that donkeys infected with a Brazilian strain of T. evansi developed a chronic disease.

Cinco jumentos, adultos foram infectados experimentalmente com cepa brasileira de Trypanosoma evansi, isolada de um cão naturalmente infectado, com o intuito de observar as alterações hematológicas, bioquímicas e histopatológicas durante a evolução da enfermidade. O curso da infecção experimental foi de 145 dias. Análise hematológica dos jumentos infectados revelou declínio nos valores de hemoglobina, hematócrito e contagem total de eritrócitos. Notou-se anemia após sucessivos picos de parasitemia. Análise bioquímica indicou aumento dos níveis de índice ictérico, globulinas séricas e diminuição dos valores séricos de albumina e glicose. Todos os jumentos infectados apresentaram aumento do baço e de sua polpa branca, aumento de linfonodos mediastínicos e congestão pulmonar. Meningoencefalite foi o principal achado histopatológico. Em algumas áreas do pedículo cerebelar foram observadas desmielinização, além de vacuolização do neurópilo. O estudo mostrou que jumentos infectados com a cepa brasileira do T. evansi desenvolveram doença crônica.

Hematological, biochemical and anatomopathological aspects of the experimental infection with Trypanosoma evansi in dogs

The course of experimental T. evansi infection in four dogs was followed for 82 days and hematological, biochemical and anatomopathological findings were studied. Infected animals showed progressive decrease in red blood cell count and hemoglobin concentration, leading to anemia which persisted from the third week post-infection until the end of the study. Leucopenia and neutropenia were observed between weeks 2 and 5 of the infection. The infected dogs developed hyperproteinemia and a decrease in the albumin:globulin ratio was observed. Aspartate aminotransferase and alamine aminotransferase levels increased significantly in infected dogs in comparison to control dogs. Histological changes observed in all infected animals consisted of lymphoid hyperplasia in spleens and lymph nodes and centrilobular degeneration and periportal mononuclear cell accumulation in the liver. A massive mononuclear cell infiltration of the myocardium was seen in three dogs and a nonsuppurative meningoencephalitis was evidente in two infected animals

Isolation of Babesia bigemina and Babesia bovis merozoites by ammonium chloride lysis of infected erythrocytes

1. We describe the isolation of viable merozoites from erythrocytes infected with Babesia bovis or Babesia bigemina organisms by ammonium chloride lysis. 2. Parasite morphology was examined by both light and transmission electron microscopy. Erythrocyte-free parasites maintain their viability and infectivity, retain their antigenicity and are suitable for use in the indirect fluorescent antibody assay

Transmissäo transmamária de larvas de nematóides gastrintestinais a bezerros búfalos. II. Larvas de Toxocara vitulorum / Transmammary passage of gastrointestinal nematodes larvae to buffalo calves. II. Toxocara vitulorum

A via transmamária de transmissäo de Toxocara vitulorum foi evidenciada pela presença de larvas no colostro/leite de 14 (70 por cento) búfalos, no período compreendido entre o parto e o 26§ dia pós-parto. A maioria dos animais mostrou-se positiva durante os primeiros 10 dias pós-parto (54,8 por cento). Pelos exames coprológicos foi constatada a presença de ovos de T. vitulorum, principalmente durante a lactaçäo. Os ovos deste helminto começaram a ser detectados nas fezes dos bezerros do 6§ ao 29§ dia de vida. Destes animais, 26,7 por cento e 6,3 por cento já estavam parasitados nos primeiros 10 dias de vida, 66,7 por cento e 41,2 por cento até o 20 e 100 e 100 por cento até os 30, nos anos de 1989 e 1990, respectivamente

A technique for collecting saliva from the cattle-tick Boophilus microplus (canestrini, 1887) using chemical stimulation: environmental and temporal influences on secretion yield

1. Injection of a pilocarpine solution into the hemocoele of female B. microplus through the respiratory spiracle induced the flow of limpid saliva, collected from the mouth parts with a capillary tube. 2. The time interval between the detachment of the tick from its host and chemical stimulation influenced the volume of saliva secreted; secretion was greater during the first 2 h after detachment. 3. There is a positive correlation between salivary yield and both environmental temperature and relative humidity