Evidence for inter- and intra-species biofilm formation variability among a small group of coagulase-negative staphylococci

Coagulase-negative staphylococci (CoNS) are common bacterial colonisers of the human skin. They are often involved in nosocomial infections due to biofilm formation in indwelling medical devices. While biofilm formation has been extensively studied in Staphylococcus epidermidis, little is known regarding other CoNS species. Here, biofilms from six different CoNS species were characterised in terms of biofilm composition and architecture. Interestingly, the ability to form a thick biofilm was not associated with any particular species, and high variability on biofilm accumulation was found within the same species. Cell viability assays also revealed different proportions of live and dead cells within biofilms formed by different species, although this parameter was particularly similar at the intra-species level. On the other hand, biofilm disruption assays demonstrated important inter- and intra-species differences regarding extracellular matrix composition. Lastly, confocal laser scanning microscopy (CLSM) experiments confirmed this variability, highlighting important differences and common features of CoNS biofilms. We hypothesised that the biofilm formation heterogeneity observed was rather associated with biofilm matrix composition than with cells themselves. Additionally, our results indicate that polysaccharides, DNA and proteins are fundamental pieces in the process of CoNS biofilm formation.

Continuous fungal treatment of non-sterile veterinary hospital effluent: pharmaceuticals removal and microbial community assessment

Source point treatment of effluents with a high load of pharmaceutical active compounds (PhACs), such as hospital wastewater, is a matter of discussion among the scientific community. Fungal treatments have been reported to be successful in degrading this type of pollutants and, therefore, the white-rot fungus Trametes versicolor was applied for the removal of PhACs from veterinary hospital wastewater. Sixty-six percent removal was achieved in a non-sterile batch bioreactor inoculated with T. versicolor pellets. On the other hand, the study of microbial communities by means of DGGE and phylogenetic analyses led us to identify some microbial interactions and helped us moving to a continuous process. PhAC removal efficiency achieved in the fungal treatment operated in non-sterile continuous mode was 44 % after adjusting the C/N ratio with respect to the previously calculated one for sterile treatments. Fungal and bacterial communities in the continuous bioreactors were monitored as well.

Searching for therapeutic strategies in a mouse modelo of Machado-Joseph disease: targeting proteostases

Tese de Doutoramento em Ciências da Saúde

Utentes da Consulta Externa de Ginecologia/Obstetrícia da Maternidade Júlio Dinis

Com o objectivo de fazer a caracterização da situação social e demográfica e das condições de saúde médica e psicológica das utentes da Consulta Externa de Ginecologia/Obstretícia da Maternidade Júlio Dinis e de seus companheiros, duzentas mulheres e cento e setenta e cinco homens (N=375) foram entrevistados com base num questionário desenhado para o efeito, durante o primeiro trimestre de gestação. Observamos o desfavorecimento social e económico da amostra, particularmente no grupo das mulheres. Constatamos que a situação matrimonial e familiar é estável; no entanto, muitos agregados familiares são recentes, incluem outros familiares e este é um primeiro filho do casal. A rede de apoio social e emocional da amostra é geralmente constituída por familiares, estando mais presente para as mulheres do que para os homens e muitas vezes o companheiro não é referido como confidente, sobretudo pelas mulheres. A gestação não é geralmente de risco; não obstante, a presença frequente de problemas psicológicos uma pior aceitação inicial da gravidez no caso das mulheres. Os hábitos de vida tornam-se mais saudáveis com a gestação; no entanto, é ainda elevado o consumo de substâncias, como o tabaco, pela grávida. Problemas ginecológicos e obstétricos foram referidos, assim como a presença de adversidades na história psicológica e desenvolvimental dos participantes. Concluímos que as utentes da Consulta Externa de Ginecologia/Obstetrícia da Maternidade Júlio Dinis e seus companheiros apresentam indicadores relevantes de risco médico, psicológico e social que devem ser considerados na prestação de melhores cuidados de saúde.

Enteroscopia por cápsula e doença de Crohn: Caminhos para a otimização

Tese de Doutoramento em Medicina

Development of polymeric nanoparticles containing neuroprotective compounds of Hypericum perforatum

Tese de Doutoramento em Biologia das Plantas - MAP BIOPLANT

Pre-clinical trials for Machado-Joseph Disease: Hypothesis-based and hypothesis-free therapeutic approaches

Tese de Doutoramento em Ciências da Saúde