Accuracy of quantitative polymerase chain reaction in samples of frozen and paraffin-embedded healthy skin for the diagnosis of canine visceral leishmaniasis / Acurácia da reação em cadeia da polimerase quantitativa em amostras de pele íntegra congelada e parafinada no diagnóstico da leishmaniose visceral canina

The purpose of the present work was to evaluate the accuracy of quantitative polymerase chain reaction (qPCR) performed on samples of fresh frozen tissue (FT) and formalin-fixed, paraffin-embedded (FFPE) healthy skin. This is a validation study conducted with samples from 46 dogs from an endemic area in Brazil. After sample collection, DNA extractions were conducted using commercial kits and qPCR was oriented to kinetoplast DNA (kDNA) targets of the Leishmania infantum species. The results obtained for the FFPE samples showed 63.6% sensitivity and 77.1% specificity, whereas those obtained for the FT samples showed 100% and 48.6%, respectively. Poor agreement was observed for the results of the qPCR technique with FT and FFPE samples. Our results suggest freezing as the most suitable conservation method for the formation of sample databases considering DNA recovery.(AU)

O objetivo deste trabalho foi avaliar a acurácia da PCR quantitativa (qPCR) realizada em amostras de pele íntegra congelada (FT) e parafinada (FFPE). Trata-se de um estudo de validação, com amostras provenientes de 46 cães de uma área endêmica no Brasil. Após as coletas de amostras, as extrações de DNA foram realizadas utilizando-se kits comerciais, e a qPCR foi orientada para alvos do kDNA da espécie Leishmania infantum. Os resultados obtidos para as amostras FFPE foram 63,6% de sensibilidade e 77,1% de especificidade; para as amostras FT, 100% e 48,6%, respectivamente. A concordância dos resultados da técnica de qPCR com amostras FT e FFPE foi pobre. Os resultados sugerem que o congelamento é o método mais adequado de conservação para banco de amostras para recuperação de DNA.(AU)

Avaliação da confiabilidade entre dois observadores em exames citopatológico e imunocitoquímico de aspirado de medula óssea no diagnóstico da leishmaniose visceral canina / Reliability evaluation between two evaluators in the cytopathologic and immunocytochemical exams from bone marrow aspirate in the canine visceral leishmaniasis diagnosis

Visceral leishmaniasis is a zoonosis in which the dog appears as the main source of infection in urban areas. Its diagnosis is complex and the cytopathological exam is a fast and cheap alternative to parasite direct visualization and its sensitivity can be increased by immunocytochemistry, though with a higher cost. The accuracy of such methods is dependent on the microscopist's experience and therefore, this study evaluated the reliability of such techniques between two observers, from bone marrow aspirates of 50 dogs from an endemic area for the disease. The parasitological culture in Novy-MacNeal-Nicolle medium was used as the reference standard. Among the main findings, the sensitivities obtained by observers I and II were respectively 62.5% and 37.5%, while specificities were 81.1% and 100%. On immunocytochemistry evaluation, the sensitivity was 0% for both evaluators and the specificity 97.3% and 100%. The agreement between evaluators was weak (κ = 0.167) for the cytopathological test and it could not be evaluated for immunocytochemistry, for which there was no detection by the evaluator II. The agreements among the diagnostic methods and the standard reference for the observer I were reasonable (κ = 0.364) for cytopathological examination and bad (κ = -0.041) for immunocytochemistry. For observer II, such agreement could be assessed only for the cytopathological test, being moderate (κ = 0.497). The results point to the possible expertise difference between evaluators, with the evaluator II demonstrating greater experience when interpreting the citopathological test. Although there was the expected sensitivity increase with immunocytochemistry, the technique used in this study was not effective for the diagnosis of infection, regardless of the evaluator.(AU)

Avaliação da qualidade do colostro e transferência de imunidade passiva em animais mestiços Holandês Zebu / Colostrum quality evaluation and passive immunity transfer in crossbred Holstein Zebu cattle

O objetivo desta pesquisa foi avaliar a qualidade do colostro de vacas mestiças Holandês Zebu e a transferência de imunidade a seus bezerros. Efeitos de ordem de parto, sexo do bezerro, estação do ano e grupo genético foram estudados em vacas distribuídas em quatro grupos genéticos. Amostras de sangue dos bezerros foram coletadas aos três dias de vida. Foi avaliada a concentração de proteína total no soro (PT) por refratometria e espectrofotometria. As amostras de colostro apresentaram alta qualidade, com concentração média de Ig de 78,5mg/mL. Houve adequada transferência de imunidade passiva, com 88,3% dos bezerros com PT acima de 5,5g/dL. Não houve efeito de ordem de parto, sexo do bezerro, estação do ano e grupo genético da vaca na qualidade do colostro e na PT (P>0,05). Vacas F1 produziram, em média, colostro de alta qualidade e houve sucesso na transferência de imunidade passiva.

The objective of this paper was to evaluate crossbred Holstein Zebu cows colostrum quality and passive immunity transfer to their calves. Parity, calf sex, season of the year and cow genetic group effects in both responses were analyzed. Quality (immunoglobulin - Ig - concentration) was measured in colostrum samples of 186 crossbred cows from four different genetic groups with a colostrometer. Calf’s blood samples were collected on the third day of life. Serum total protein concentration (PT) was measured through refractometry and spectrophotometry. Colostrum samples were classified as high quality and showed mean Ig concentrations of 78.5mg/mL. Passive immunity transfer was successful, since 88.3% of calves had PT higher than 5.5g/dL. There was no effect of parity, calf sex, season of the year or cow genetic group in colostrum quality or serum total protein concentration (P>0.05). Crossbred Holstein Zebu cows produced high quality colostrums. There was success in passive immunity transfer to the calves.

Experimental infection of canine peritoneal macrophages with visceral and dermotropic Leishmania strains

A study was carried out using macrophages cultured from the peritoneal exudate of dogs infected in vitro with three species of Leishmania: L. (L.) chagasi, L. (Viannia) braziliensis and L. (L.) amazonensis with the aim of investigating the growth kinetics and infectivity of these species in the host cell. Results were expressed as the percentage of macrophages infected measured at 24 hr intervals over six days in RPMI - 1640 culture medium at a temperature of 34-35oC. The findings open the possibility of using canine peritoneal cells as a model for the screenning of leishmanicide drugs and to study the pathogenesis of these species.

Hematoma de bainha dos retos / Hematoma of the rectus abdominis sheaths

Os autores relatam sua experiência com 4 casos de hematoma de bainha dos retos, analisando o diagóstico e a conduta terapêutica