Propolis components accountable for bactericidal accomplishment and antibiofilm activity

This study aimed at evaluating antimicrobial and antibiofilm activity of phenolic compounds present in propolis ethanol extracts (PEE). Seventy per cent ethanol extracts from seven types of propolis, one Green, two Red and four Brown collected in four Brazilian States were prepared and total phenolics, flavonoids, tannins and anthocyanins were assessed by high-performance liquid chromatography (HPLC). Minimum bactericidal concentration (MBC) and inhibitor effect on Staphylococcus aureus biofilm formation and capacity to disrupt established biofilms were assessed towards eight S. aureus isolates from milk of small ruminants with mastitis, one methicillin-resistant S. aureus (MRSA) and S. aureus ATCC 25923. To evaluate different propolis components accountability for bactericidal accomplishment and antibiofilm activity, the results were analysed by the non-parametric Spearman coefficient. Results of phenolic compounds were 216,21 to 312,08 gallic acid milligram equivalent per extract gram (mg EGA/g) of total phenolics, 55,08 to 140,6 quercetin milligram equivalent per extract gram (mg EQ/g) of flavonoids, 118,51 to 3766,16 catechin milligram equivalent per extract gram (mg EC/g) of tannins and 1,03 to 8,39 milligram per extract gram (mg/g) of anthocyanins. Red1 and Red2 showed higher tannin contents, while Red2 exhibited superior amount of anthocyanins and total phenolics. Brown3 presented higher flavonoid quantity. Green, Red1 and Red2 PEE showed the lowest levels of flavonoids, but the higher antimicrobial activity. Most PEE exhibit bactericidal activity at a concentration of 1.6 mg/mL. Brown4 PEE showed the worst capacity to inhibit S. aureus. Green PEE showed to be the most efficient in both preventing and disrupting biofilm. All PEE studied exhibited a better inhibitory activity prior-to than post-biofilm formation. According to non-parametric Spearman correlation analysis, there seems to be a significant negative correlation between the ability to disrupt biofilm and both tannins and anthocyanins contents.

Tornar-se doutor: a relação de orientação e o desenvolvimento do/a doutorando/a

Apesar do estudo dos processos educativos no ensino superior ser um tópico bastante explorado pela Psicologia, o estudo do processo de doutoramento parece ter sido relegado para segundo plano ao longo dos anos. O presente estudo procurou analisar a perceção de desenvolvimento de estudantes de doutoramento (em termos de ganhos e perdas) e a relação de orientação (em termos de tipo de relação e qualidade percebida da relação), bem como o impacto dessa relação na perceção de desenvolvimento pessoal. Participaram neste estudo 308 estudantes de doutoramento de três universidades portuguesas. Os principais resultados obtidos parecem indicar que os doutorandos tendem a perceber a qualidade da relação de forma positiva, que estes percebem os orientadores como cooperantes, próximos e respeitadores da autonomia do estudante, e que estes tendem a perceber principalmente ganhos desenvolvimentais. De uma forma geral observou-se também que algumas dimensões do tipo de relação e da qualidade da relação parecem ter uma influência significativa na perceção de ganhos e perdas; On becoming a PhD: The relation of supervision and the development of the doctorate Abstract: Despite the study of educational processes in higher education is a topic extensively explored by Psychology, the study of the doctoral process seems to have been relegated to the background over the years. This study aimed to analyze the perception of development of PhD students (in terms of gains and losses) and the supervision relationship (in terms of type of relationship and perceived quality of the relationship), and the impact of this relationship on the perception of personal development. The sample consisted of 308 doctoral students from three portuguese universities. The main results seem to indicate that doctoral students tend to perceive the quality of the relationship as positive, that they perceive supervisors as cooperant, close and respectful for students’ autonomy, and that they tend to perceive mainly developmental gains. In general, it is also noted that some dimensions of the type of relationship and the relationship would appear to have a significant influence on the perception of gains and losses.