Molecular detection of virulence factors among food and clinical Enterococcus faecalis strains in South Brazil

The present report aimed to perform a molecular epidemiological survey by investigating the presence of virulence factors in E. faecalis isolated from different human clinical (n = 57) and food samples (n = 55) in Porto Alegre, Brazil, collected from 2006 to 2009. In addition, the ability to form biofilm in vitro on polystyrene and the β-haemolytic and gelatinase activities were determined. Clinical strains presented a higher prevalence of aggregation substance (agg), enterococcal surface protein (esp) and cytolysin (cylA) genes when compared with food isolates. The esp gene was found only in clinical strains. On the other hand, the gelatinase (gelE) and adherence factor (ace) genes had similar prevalence among the strains, showing the widespread occurrence of these virulence factors among food and clinical E. faecalis strains in South Brazil. More than three virulence factor genes were detected in 77.2% and 18.2% of clinical and food strains, respectively. Gelatinase and β-haemolysin activities were not associated with the presence of gelE and cylA genes. The ability to produce biofilm was detected in 100% of clinical and 94.6% of food isolates, and clinical strains were more able to form biofilm than the food isolates (Student's t-test, p < 0.01). Results from the statistical analysis showed significant associations between strong biofilm formation and ace (p = 0.015) and gelE (p = 0.007) genes in clinical strains. In conclusion, our data indicate that E. faecalis strains isolated from clinical and food samples possess distinctive patterns of virulence factors, with a larger number of genes that encode virulence factors detected in clinical strains.

A three-step molecular protocol employing DNA obtained from dried blood spots for neonatal screening for 45, X Turner syndrome

Turner syndrome (TS) is one of the most common human chromosomal abnormalities; it is characterized by the presence of one normal X chromosome and the complete or partial loss of the second X chromosome. The early recognition of TS patients allows for adequate therapy for short stature and pubertal sex steroid substitution. We developed a cost-effective molecular diagnostic tool that can be used to identify 45,X TS patients from dried blood spots, for possible use in neonatal screening for TS. We used a three-step method for 45,X TS detection: i) DNA extraction from dried blood spot samples, ii) pre-PCR HpaII digestion (methylation-sensitive enzyme) and iii) GeneScan analysis of selected cases. DAX-1 gene amplification was used to recognize DNA integrity, and the androgen receptor gene (Xq11-12), which is both a highly polymorphic and methylated gene, was used to determine the number of X chromosome alleles. Using this three-step diagnostic procedure, we detected apparent TS in 1/304 (0.33%) samples; such individuals should be submitted to clinical examination and karyotype confirmation. The three-step 45,X TS neonatal screening protocol is a simple, reliable, fast (under 30 h) and cost-effective diagnostic tool, useful for the neonatal detection of TS.

Saturnismo: etiopatogenia, conceitos atuais. / Saturnism: etiopathogenesis,present concepts

Conceitos atuais sobre a etiofisiopatogenia do chumbo no organismo, descrevendo-se previamente as suas vias de penetracao e absorcao, sao apresentados pelos autores. Sao descritos tambem, os mecanismos de transporte do chumbo pelo sangue periferico, bem como os locais de sua acao na sintese do heme, alem de enfantizada sua acao inibitoria sobre a atividade das enzimas dehidratase do acido deltaminolevulinico (ALAD) e ferroquelatase. Por sua experiencia, os autores consideram a dosagem quantitativa da zincoprotoporfirina (ZPP) produto da acao toxica do chumbo sobre a atividade da enzima ferroquelatase - pela hematofluorometria como o metodo ideal para o controle biologico de trabalhadores expostos ao chumbo. Descrevem, por fim, os mecanismos da acao toxica do chumbo sobre os varios orgaos em que se acumula, atraves de exposicoes continuas e prolongadas

Dosagem da zincoprotoporfirina por hematofluorometria - Um metodo simples e eficaz para o controle biologico do saturnismo. / Zincprotoporhirine dosage by hematofluorometry a simple and efficient method for the saturnism control

A dosagem quantitativa da zincoprotoporfirina ZPP - no sangue abre umanova perspectiva para o controle biologico do saturnismo. O metodo proposto e o da hematofluorometria que, atraves de um aparelho portatil de facil manipulacao por pessoal paramedico, apresenta resultados confiaveis, utilizando apenas uma gota de sangue e dispensando reagentes quimicos e puncao venosa. A ZPP indica um efeito do chumbo na sintese do heme, na medula ossea inibindo a atividade de enzima mitocondrial,a ferrolatase. Como a ZPP permanece na hemacia durante toda a sua vida (120 dias), serve como indicador biologico tardio (mesmo apos cessada a exposicao do chumbo). A dosagem de chumbo no sangue indica a absorcao, que nem sempre corresponde aos efeitos biologicos.Estes tem sido medidos pela dosagem da enzima ALAD no sangue, de dificil utilizacao em nosso meio. Por isso, a dosagem da ZPP pode tornar-se uma boa opcao para Servicos Medicos de Empresas, que nao dispoem de laboratorio de toxicologia industrial