Characterization of porcine Trueperella pyogenes by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), molecular typing and antimicrobial susceptibility profiling in Sao Paulo State.

Trueperella pyogenes can be found as a commensal or pathogenic bacterium among animals causing a variety of pyogenic infections in several species. The agent appears to act primarily as an opportunistic pathogen but may disseminate and produce metastatic abscesses accompanied or not by mastitis, metritis or pneumonia. In this study, 30 porcine T. pyogenes strains were identified by MALDI-TOF MS and 16S rRNA sequencing and further evaluated in relation to their resistance and genetic profiles through broth microdilution and single enzyme AFLP. All strains were susceptible to ß-lactams, florfenicol, gentamicin, spectinomycin and tiamulin. The highest resistance rates were observed for sulfonamides, tetracyclines and clindamycin. All isolates could be characterized by SE-AFLP presenting more than 80% of similarity, despite their distinct origins. Four genotypes were detected with the segregation of T. pyogenes ATCC 19411 from Brazilian T. pyogenes strains. No correlation between genotypes and isolates origins and susceptibility profile was observed.

Canine visceral leishmaniasis: diagnostic approaches based on polymerase chain reaction employing different biological samples.

The accurate diagnosis of canine visceral leishmaniasis (CanL) is essential for visceral leishmaniasis control. To this end, DNA detection on different biological samples has been employed. In this study, we report the use of polymerase chain reaction (PCR) assay on samples such as buffy coat, bone marrow, intact skin and cutaneous ulcers fragments, and lymph node aspirate collected from 430 dogs to determine the suitable biological sample for use in CanL diagnosis. The PCR results were correlated with clinical status and other tests previously performed. Leishmania chagasi DNA was detected in 14.6% (n = 63) of the dogs investigated, regardless of the sample analyzed. Our results showed that symptomatic cases were easily diagnosed when compared to asymptomatic animals; however, the PCR proved to be very useful for Leishmania DNA detection, mainly in lymph node aspirate (41; 9.6%), irrespective of the clinical status of the dog. The finding that the lymph node aspirate produced high positivity rates and the fact that this specimen was obtained by noninvasive methods highlight its use in epidemiological survey by PCR for CanL diagnosis.

Padronização da técnica de nanopartícula de ouro não modificada (AuNPs) para detecção de Actinobacillus pleuropneumoniae em pulmões de suínos / Standardization of unmodified gold nanoparticle (AuNPs) for detection of Actinobacillus pleuropneumoniae in swine lungs

Testes diagnósticos baseados na detecção de ácidos nucleicos sem amplificação prévia através da utilização de nanopartículas de ouro (AuNPs) têm sido descritos para várias enfermidades. Este trabalho teve como objetivo desenvolver uma técnica de AuNPs não modificada para detecção de Actinobacillus pleuropneumoniae (App). Utilizaram-se 70 amostras de pulmão de suínos, 17 sem lesão e 53 com lesões características de pneumonia, objetivando a detecção de App. O oligonucleotídeo utilizado foi baseado no gene ApxIV. O teste de AuNPs apresentou sensibilidade de 93,8 por cento e especificidade de 84,6 por cento quando comparado com a detecção pela PCR. Os resultados mostraram boa concordância entre os testes de AuNPs e a PCR, sendo que a técnica pode ser utilizada como alternativa aos testes convencionais, já que é de fácil e rápida execução e não exige infraestrutura e mão de obra especializada.

Based on diagnostic tests for the detection of nucleic acids without amplification through the use of gold nanoparticles (AuNPs) have been described for various diseases. This study aimed to develop a technique of unmodified AuNPs to detect Actinobacillus pleuropneumoniae (App). We used 70 lung samples from pigs, 17 with and 53 without characteristic lesions of pneumonia, to detect App. The primer used was based on ApxIV gene. The AuNPs test had a sensitivity of 93.8 percent and specificity of 84.6 percent when compared with PCR detection. The results showed good agreement between AuNPs and PCR testing, and the technique can be used as an alternative to conventional tests, since it is quick and easy, and does not require implementation infrastructure and skilled labor.