Differential gene expression pattern and plasma sex steroids during testicular development in Genyatremus luteus (Perciforme: Haemulidae) (Bloch, 1790).

The aim of the current study is to evaluate gene expression patterns of LH (lhr) and estrogen (er) receptors and plasma steroid levels during testicular development in Genyatremus luteus. Males were histologically classified as immature (n=7), maturing (n=7) and mature (n=7), based on the cellular structure of their testes. Plasma 11-KT concentration recorded peak at the final maturation stage. The highest plasma 17α-OHP concentrations were observed at the immature stage; they decreased at the maturation and mature stages. On the other hand, 17ß-estradiol (E2) recorded higher concentrations at the maturation stage. Er expression has significantly increased along the maturational development of animals' testes. The mRNA observed for the LH receptor has decreased from immature to maturing stage; it presented expression peak at the mature stage. There was high association between receptor gene expression and plasma steroid levels, mainly E2. The current study was the first to feature different reproductive maturation stages in male G. luteus specimens, based on cellular, endocrine and molecular aspects. In addition, it has shown that the gene expression profile for er and lhr receptors, as well as plasma 11-KT and E2 concentrations, are directly linked to testicular maturation, although they are not necessarily associated with the gonadosomatic index.

Citometria de fluxo no diagnóstico da leishmaniose visceral canina / Flow cytometry used in canine visceral leishmaniasis diagnosis

Descreve-se a padronização de nova metodologia para detecção de anticorpos antiformas promastigotas fixadas de L. (L.) chagasi, por citometria de fluxo (AAPF-IgG), sua aplicabilidade e desempenho na identificação de casos de leishmaniose visceral canina (LVC). Foram avaliados dois grupos de cães classificados pela reação de imunofluorescência indireta (RIFI), como: não reatores (NR, n=10) e reatores (R, n=50) dos quais foram coletadas amostras de sangue (soro) para realização dos testes laboratoriais. Os resultados relacionados ao estabelecimento, aplicabilidade e desempenho da metodologia AAPF-IgG demonstraram que essa metodologia possibilita a identificação de uma região de reatividade diferencial entre cães NR e R, no soro diluído a 1:2048 e o valor de 20 por cento de parasitos fluorescentes positivos (PPFP) como ponto de corte entre resultados positivos e negativos, mostrando que a AAPF-IgG aplica-se na identificação de casos de LVC, possibilitando distinguir 96 por cento de cães R como positivos e 100 por cento de cães NR como negativos. Esses resultados em conjunto sugerem que a utilização da AAPF-IgG pode ser um novo instrumento para ensaios clínicos de diagnóstico sorológico da LVC.

The current study evaluated the standardization of a new methodology for detection of anti-fixed L. (L.) chagasi promastigote antibodies by flow cytometry (AAPF-IgG), as well its applicability and performance in the identification of cases of Canine Visceral Leishmaniasis (CVL). Two groups of dogs were classified by RIFI (gold standard) as no reactors (NR, n=10) and reactors (R, n=50). Blood samples were collected and used for the laboratorial tests (RIFI and AAPF-IgG). The results showed that the new AAPF-IgG assay makes possible the identification of an area of differential reactivity between dogs NR and R at the dilution of 1:2048 and 20 percent of percentage of positive fluorescent parasite as the cut point among positive and negative results. The AAPF-IgG assay was able to distinguish 96 percent of R dogs as positive and 100 percent of NR dogs as negative. Hence, those data support the applicability of flow cytometry AAPF-IgG method as a new instrument for serological diagnosis of CVL.