In colonies of Melipona scutellaris Latreille, 1811 workers can be found with four ganglion nerve cells, a morphological characteristic of the queen. It is hypothesized that these workers, called intercastes, or phenocopies, are phenotypically-like workers, but genotypically identical to queens due to this specific trait. Workers with the same number of ganglion as queens seem to be intercastes between queens and workers. Our objective was to analyze the mRNA pro files of workers, queens, and intercastes of M. scutellaris through DDRT-PCR. Three hundred (300) pupae with white eyes were collected and externally identified according to the number of abdominal nerve ganglions: workers (5 ganglions), queens (4 ganglions) and intercastes (4 ganglions). The analysis identified differentially expressed transcripts that were present only in workers, but absent in intercastes and queens, confirming the hypothesis, by demonstrating the environmental effect on the queen genotype that generated phenotype-like workers.

We used the multiplex semi-quantitative reverse-transcriptase PCR (RT-PCR) to investigate kallikrein 2 and 3 (KLK2 and KLK3) mRNA levels in prostate tissue from 42 prostate cancer patients, 33 of whom were also assessed for peripheral blood KLK2 expression by qualitative semi-nested RT-PCR. We found that KLK2 was an important tissue biomarker for distinguishing between prostate cancer patients and those with benign prostatic hyperplasia, particularly when KLK2 expression was > 60% of that of the beta2-microglobulin constitutive gene. Patients with an average relative expression value > 0.6 (cutoff value) had an eleven-fold higher chance of having prostate cancer. When one or two tissues samples were evaluated for KLK2 expression using the cutoff value the estimated chance of having prostate cancer was increased by seven times for one positive sample and 45 times for two positive samples. There was no significant correlation between KLK3 gene expression and prostate cancer diagnosis. Logistic regression for blood and tissue KLK2 expression successfully detected 92% of the prostate cancer cases. The detection of KLK2 in blood showed a sensitivity of 59% and a specificity of 82%. This study indicates that the KLK2 gene may be a useful molecular marker for the diagnosis of prostate cancer and that analysis of KLK2 expression in blood and tissues could provide a novel approach for the clinical investigation of this type of cancer.

Heterodera glycines Ichinohe, o nematóide de cisto da soja (SCN), foi detectado no Brasil em 1.992 e desde então tem provocado perdas consideráveis à produtividade da soja brasileira. Populações de SCN apresentam grande diversidade genética, o que dificulta o manejo dessa cultura em áreas infestadas. Os objetivos desta pesquisa foram investigar a possível variação genética de dezesseis populações de SCN amostradas nas regiões Centro Oeste e Sudeste do Brasil, utilizando a técnica do RAPD (amplificação casualizada de DNA polimórfico), bem como estabelecer marcadores RAPD específicos para a raça 3 do SCN. Nossos resultados mostraram que os marcadores RAPD podem ser utilizados em estudos de variabilidade genética entre populações de SCN e dentro de raças deste nematóide, bem como podem ser usados no monitoramento de dinâmica populacional deste patógeno. O "primer" OPA-07 foi considerado satisfatório como marcador molecular para a raça 3, enquanto a análise eletroforética dos fragmentos de DNA amplificados com a utilização do "primer" OPA-10 detectou ligeira variação nas populações de SCN identificadas como raça 3. A população do SCN oriunda de Chapadão do Céu, GO - amostra 2 - foi a geneticamente mais distante, quando comparada às demais usadas neste estudo.

Heterodera glycines Ichinohe, the soybean cyst nematode (SCN) was detected in Brazil in 1992 and since then it has been causing losses to Brazilian soybean crop yields. SCN populations have great genetic diversity which makes it difficult to manage this disease. The objectives of this research were to investigate the genetic variation of 16 SCN populations sampled in middle western and southeastern Brazil, utilizing random amplified polymorphic DNA (RAPD) techniques, and to establish useful and specific RAPD markers for SCN race 3. RAPD markers demonstrated genetic variability among and within SCN populations, and they could be used for monitoring nematode population dynamics. The OPA-07 primer was a reliable molecular marker for race 3, while electrophoretic profile analysis of DNA fragments amplified with OPA-10 primer detected slight variation within those populations identified as race 3. The SCN population from Chapadão do Céu, GO - sample 2 - was the most genetically distant from the other populations.