Prática de ensino supervisionada em Educação Pré-escolar e Ensino do 1.º Ciclo do Ensino Básico

O presente relatório foi realizado no âmbito da unidade curricular de Prática de Ensino Supervisionada, inserida no plano de estudos do curso de Mestrado em Educação Pré- Escolar e Ensino do 1.º Ciclo do Ensino Básico, da Escola Superior de Educação do Instituto Politécnico de Bragança. A intervenção em contexto de Educação Pré- Escolar teve a duração de 180 horas, das quais 24 horas foram em contexto Creche. A intervenção em contexto de 1.º Ciclo do Ensino Básico teve, igualmente, a duração de 180 horas. Na Educação Pré- Escolar, trabalhamos com um grupo de 19 crianças, de 3 e 4 anos de idade, e no 1.º Ciclo do Ensino Básico, com um grupo de 23 crianças que integravam o 3.º ano de escolaridade, com 9 anos de idade. Ambos os contextos pertenciam à rede pública. Para proporcionar um conhecimento mais alargado das instituições e da realidade de cada contexto e grupo de crianças, foi elaborada a caracterização dos dois contextos. Ao longo da prática procurámos desenvolver atividades que respondessem às necessidades e interesses das crianças, de forma a criar momentos de participação ativa, de partilha de saberes e de cooperação no âmbito das Orientações Curriculares para a Educação Pré-escolar, das Metas Curriculares e do Programa do 1.º Ciclo do Ensino Básico. Tendo em conta que o tema autonomia se revelou uma preocupação no decorrer da nossa Prática de Ensino Supervisionada, surgiu uma questão que nos fez refletir: Como é que o professor estagiário perceciona a construção da autonomia da criança, em contexto educativo? Tentando dar resposta a esta questão definimos três objetivos que orientaram o nosso percurso investigativo: (i) perceber de que forma é que a rotina diária influência na autonomia (ii) perceber a importância da organização do espaço no desenvolvimento da autonomia das crianças nos contextos do Educação Pré-Escolar e do 1.º Ciclo do Ensino Básico. e (iii) perceber como as experiências de ensino/aprendizagem ajudam na construção da autonomia; Como instrumentos de recolha de dados recorremos à observação participante, registo de notas de campo e de fotografias (sempre que possível). A metodologia utilizada foi a investigação qualitativa de natureza interpretativa. Este tipo de investigação apresenta os resultados através de narrativas com descrições contextuais e citações dos participantes, e que desta forma transmitem as ações e reações que os mesmos tiveram ao longo da prática em ambos os contextos. Os resultados recolhidos nesta investigação, referem que o estagiário perceciona a construção da autonomia da criança como um percurso longo, gratificante e com evoluções mais significativas na Educação Pré-Escolar.

Study of antioxidant, antiproliferative and apoptosis-inducing properties of wild mushrooms from the Northeast of Portugal

Mushrooms are known as a powerful source of bioactive compounds including antioxidants, inhibitors of human tumour cell lines growth, inducers of apoptosis and enhancers of immunity. Indeed, many pre-clinical studies have been conducted in human tumour cell lines and in some cases a number of compounds isolated from mushrooms have followed to clinical trials. The Northeast of Portugal is one of the European regions with higher wild mushrooms diversity. However, to our knowledge, no studies had been conducted so far to verify their bioactivities. The main aim of this work was the evaluation of the bioactive properties (antioxidant properties and growth inhibitory potential on human tumour cell lines) of wild edible mushrooms collected in the Northeast of Portugal. Once properly identified, methanolic, ethanolic and boiling water extracts were prepared from thirty eight wild mushroom species collected in that region. Chemical characterization was obtained by high performance liquid chromatography (HPLC) coupled to a photodiode array detector (DAD) or to a refraction index detector (RI). Antioxidant activity assays were carried out in those extracts, including evaluation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging capacity, reducing power and inhibition of β-carotene bleaching. Extract-induced cell growth inhibition was assessed with the sulforhodamine B assay in four human tumour cell lines (NCI-H460 - lung cancer, MCF-7 -breast cancer, HCT-15 -colon cancer and AGS - gastric cancer). The effects on cell cycle profile and apoptosis were evaluated by flow cytometry and the effect on the expression levels of proteins related to cell cycle and apoptosis was further investigated by Western blotting. Three wild edible mushroom species revealed growth inhibitory activity in the studied human tumour cell lines: Clitocybe alexandri ethanolic extract, Lepista inversa methanolic extract and Suillus collinitus methanolic extract. C. alexandri ethanolic extract induced an S-phase cell cycle arrest and increased the percentage of apoptotic cells, in the NCI-H460 cell line. The analysed mushroom species also provided interesting antioxidant potential, mainly the boiling water extract of L. inversa which showed the highest DPPH radical scavenging activity, reducing power and β-carotene bleaching inhibition. S. collinitus methanolic extract induced a slight increase in the number of cells in G1, with a concomitant decrease in the percentage of cells in the S phase of the cell cycle and an increase in the percentage of apoptotic cells, in the MCF-7 cell line. The combined use of the S. collinitus methanolic extract and etoposide caused a greater decrease in the percentage of cell growth, when compared to either of them used individually, indicating the potential benefit of this combination. The tested extracts were chemically characterized and protocatechuic, p-hydroxybenzoic, p-coumaric and cinnamic acids were the main compounds identified on the phenolic (methanolic and ethanolic) extracts, while mannitol, trehalose and arabinose were the main sugars found in the polysaccharidic (boiling water) extracts after hydrolysis. The individual compounds identified in the extracts were submitted to a screening of tumour cells growth inhibitory activity, but only the phenolic acids and a related compound, cinnamic acid, presented activity. This compound was found to be the most potent one regarding cell growth inhibition in the NCI-H460 cell line. The effect of the individual and combined treatment with the identified compounds was also evaluated. Cinnamic and protochatequic acids caused a statistically significantly reduction in the number of viable cells. In addition, p-hydroxybenzoic acid did not show any significantly reduction in the viable cell number. Nevertheless, it was verified that the concomitant use of the three compounds provided the strongest decrease in the viable cell number, suggesting a possible concomitant effect of those compounds. Overall, the present work has contributed to further understand the bioactive potential of wild edible mushrooms from the Northeast of Portugal. This study allowed to identify some species with antioxidant or tumour cell growth inhibitory potential.

HPLC-DAD-ESI/MS phenolic characterization and biological activity of Equisetum giganteum L.

Naturally-occurring phytochemicals have received a pivotal attention in the last years, due to the increasing evidences of biological activities. Equisetum giganteum L., commonly known as “giant horsetail”, is a native plant from Central and South America, being largely used in dietary supplements as diuretic, hemostatic, antiinflammatory and anti-rheumatic agents [1,2]. The aim of the present study was to evaluate the antioxidant (scavenging effects on 2,2-diphenyl-1-picrylhydrazyl radicals- RSA, reducing power- RP, β-carotene bleaching inhibition- CBI and lipid peroxidation inhibition- LPI), anti-inflammatory (inhibition of NO production in lipopolysaccharidestimulated RAW 264.7 macrophages) and cytotoxic (in a panel of four human tumor cell lines: MCF-7- breast adenocarcinoma, NCI-H460- non-small cell lung cancer, HeLa- cervical carcinoma and HepG2- hepatocellular carcinoma; and in non-tumor porcine liver primary cells- PLP2) properties of E. giganteum, providing a phytochemical characterization of its extract (ethanol/water, 80:20, v/v), by using highperformance liquid chromatography coupled to diode array detection and electrospray ionisation mass spectrometry (HPLC-DAD–ESI/MS). E. giganteum presented fourteen phenolic compounds, two phenolic acids and twelve flavonol glycoside derivatives, mainly kaempferol derivatives, accounting to 81% of the total phenolic content, being kaempferol-O-glucoside-O-rutinoside, the most abundant molecule (7.6 mg/g extract). The extract exhibited antioxidant (EC50 values = 123, 136, 202 and 57.4 μg/mL for RSA, RP, CBI and LPI, respectively), anti-inflammatory (EC50 value = 239 μg/mL) and cytotoxic (GI50 values = 250, 258, 268 and 239 μg/mL for MCF-7, NCI-H460, HeLa and HepG2, respectively) properties, which were positively correlated with its concentration in phenolic compounds. Furthermore, up to 400 μg/mL, it did not revealed toxicity in non-tumor liver cells. Thus, this study highlights the potential of E. giganteum extracts as rich sources of phenolic compounds that can be used in the food, pharmaceutical and cosmetic fields.