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Browsing by Issue Date, starting with "2022-10-24"

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  • Biological properties of latex, aqueous extracts and bee products of Euphorbia Officinarum L.: a short review
    Publication . Boutoub, Oumaima; Ghadraoui, Lahsen El; Miguel, Maria Graca
    Euphorbia officinarum L. is a Moroccan endemic plant known as “Tikiout” and “Daghmus” that can also be found in Mauritania, Western Sahara, and Algeria. In the present review, “Euphorbia officinarum”, “metabolites” “hemisynthesis” were the keywords used for the research in the Web search engine Google Scholar and in the database Web of Science. Triterpenes, phytosterols and ingol diterpenes were isolated and identified in the latex of Moroccan E. officinarum. More than sixty triterpenes were obtained by hemisynthesis from natural triterpenes. Some of these derivatives had insecticidal and antimicrobial activity (phytopathogenic bacteria). The total phenol content and the antioxidant and anti-α-glucosidase activities were dependent on the time and temperature of extractions and also on the plant solvent ratio. The antioxidant activity of monofloral honey of E. officinarum origin was attributed to the phenol fraction (this fraction, previously isolated from honey samples, had better activity than the entire honey).
    2022-10-24Journal article Open Access Show more
  • Estratégias de formulação com vista à melhoria dos resultados terapêuticos na doença pulmonar obstrutiva crónica: desafios e oportunidades
    Publication . Silva, Cátia Sofia Estorãos da; Grenha, Ana
    A doença pulmonar obstrutiva crónica (DPOC) é uma doença do foro pulmonar que é caracterizada por sintomas respiratórios persistentes, como a dispneia e a tosse, e uma limitação contínua do fluxo de ar. O fumo de tabaco é considerado o principal fator de risco, mas alguns fatores do indivíduo também exercem um papel importante no desenvolvimento desta patologia. Atualmente, o tratamento existente foca-se no alívio da sintomatologia através da administração de broncodilatadores de longa duração e, quando necessário e adequado, corticosteróides inaláveis. A via pulmonar continua a ser a via preferencial para o tratamento desta doença, pelo facto de permitir uma administração localizada e oferecer várias vantagens, como um início de ação mais rápido e efeitos adversos reduzidos. Porém, o pulmão é um órgão muito complexo, pelo que também existem alguns desafios na utilização desta via. Apesar de ser uma das doenças crónicas mais comuns, a DPOC continua a ser um grande problema de saúde pública, apresentando morbilidade e mortalidade crescentes. Estes dados provam que as terapêuticas convencionais nem sempre são suficientes para controlar a doença, pelo que existe uma necessidade crescente de encontrar alternativas que permitam melhorar os resultados terapêuticos. Várias estratégias de formulação têm surgido ao longo dos últimos anos para tentar colmatar os obstáculos que impedem o sucesso terapêutico nos doentes com DPOC. Neste sentido, a nanotecnologia, as terapêuticas com RNA, e outras estratégias, têm-se mostrado cada vez mais prevalentes e têm vindo a ganhar peso a nível de investigação, com o intuito de explorar as oportunidades que cada uma delas pode oferecer, bem como os desafios que terão de ser solucionados na eventualidade da sua implementação. Neste contexto, o objetivo desta dissertação consiste em explorar algumas das estratégias de formulação que estão atualmente em investigação e que apresentam resultados promissores no tratamento da DPOC, juntamente com as oportunidades e os desafios a elas associados.
    2022-10-24Master thesis Open Access Show more
  • The role of lithic bipolar technology in the adaptation of the first humans in Europe
    Publication . Horta, Pedro Ezequiel Guedes; Bicho, Nuno Gonçalo Viana Pereira Ferreira; Cascalheira, João Miguel Mico
    The means through which Homo sapiens expanded and settle d across the Old World continues to be a longstanding question in Human Evolution studies. In Europe their adaptation to the environmental setting, including the eventual assimilation and replacement of Neanderthals remains a largely unanswered topic. On e of the many reasons that may have led our species to succeed in settling in this new territory was the use of different adaptive strategies, including bipolar technology. The latter, rarely used by Neanderthals, was constantly present in Homo sapiens ass emblages between 45 30ka BP. This dissertation’s main goal is to understand if and what role this technology play ed in the adaptation of the first humans in Europe. Additionally, it aims to provide important advances in both methodology and the understandi ng of bipolar methods in Human Evolution. In order to reach these goals a combination of metanalytics and the analysis of 3 early Homo sapiens occupations was used. T his mixed approach revealed patterns of artifact use, technological traditions, efficiency evaluation, resource intensification strategies and expediency. Homo sapiens were recurrently using bipolar methods to increase their efficiency in resource exploitation making them more adaptable to environmental pressure. Bipolar knapping was used to: conserve raw material by continuously reducing raw material volumes too small or too irregular to be held in hand or as a fast solution to obtain sharp edges. Wedging was used to increase their efficiency in exploiting organic materials including carcass processing, bone shaping, bone tool production, ornament production and wood and antler shaping and processing. While this was likely not a major contributing factor to the demise of Neanderthal groups that co existed with Humans in the same territories, it was likely another piece of the puzzle that helped humans thrive over them.
    2022-10-24Doctoral thesis Open Access Show more