Historical reconstructions of raw materials based on a blue smalt coating applied to a seventeenth-century altarpiece

Based on samples cross-sections from the Main Altarpiece of the Coimbra Old Cathedral, where a blue coating performed in 1685 is observed (that was partly covered with a Prussian blue-containing overpaint), the raw materials present in this coating were reproduced and studied. Blue areas were painted with smalt in oil, according to the contract signed by Manoel da Costa Pereira in 1684 and the analysis by Le Gac in 2009. Based on these, three batches of cobalt-based glasses (S1, S2 and S3) were heated and melted in alumina crucibles in the kiln. S1 contained 6.03 % of cobalt oxide, S2 contained 2.10 %, with the addition of 1.49 % of magnesium oxide, and S3 contained 6.82 % of cobalt oxide, with the addition of 4.63% of antimony trioxide. These batches were ground mechanically with water and manually with different vehicles stated in recipes. The results were studied by means of OM, SEM-EDS, X-Ray CT, Colorimetry and Vickers HT. Different binders were also produced and analyzed by means of μ-FTIR, in order to perform their characterization and obtain Standard Spectra. Since anhydrite was identified in the ground layers, gypsum from Óbidos was also characterized by XRD. The main goal of this thesis was to study all the raw materials present in the 1685-blue coating, in order to allow the historically accurate reconstruction of the layers build-up in the next future.

Hemolytic disease of the newborn due to anti-U

Anti-U is a rare red blood cell alloantibody that has been found exclusively in blacks. It can cause hemolytic disease of the newborn and hemolytic transfusion reactions. We describe the case of a female newborn presenting a strongly positive direct antiglobulin test due to an IgG antibody in cord blood. Anti-U was recovered from cord blood using acid eluate technique. Her mother presented positive screening of antibodies with anti-U identified at delivery. It was of IgG1 and IgG3 subclasses and showed a titer of 32. Monocyte monolayer assay showed moderate interaction of Fc receptors with maternal serum with a positive result (3.1%). The newborn was treated only with 48 hours of phototherapy for mild hemolytic disease. She recovered well and was discharged on the 4th day of life. We conclude that whenever an antibody against a high frequency erythrocyte antigen is identified in brown and black pregnant women, anti-U must be investigated.

Performance of a fly ash geopolymeric mortar for coating of ordinary portland cement concrete exposed to harsh chemical environments

Premature degradation of ordinary Portland cement (OPC) concrete infrastructures is a current and serious problem with overwhelming costs amounting to several trillion dollars. The use of concrete surface treatments with waterproofing materials to prevent the access of aggressive substances is an important way of enhancing concrete durability. The most common surface treatments use polymeric resins based on epoxy, silicone (siloxane), acrylics, polyurethanes or polymethacrylate. However, epoxy resins have low resistance to ultraviolet radiation while polyurethanes are sensitive to high alkalinity environments. Geopolymers constitute a group of materials with high resistance to chemical attack that could also be used for coating of concrete infrastructures exposed to harsh chemical environments. This article presents results of an experimental investigation on the resistance to chemical attack (by sulfuric and nitric acid) of several materials: OPC concrete, high performance concrete (HPC), epoxy resin, acrylic painting and a fly ash based geopolymeric mortar. Three types of acids, each with high concentrations of 10%, 20% and 30%, were used to simulate long term degradation by chemical attack. The results show that the epoxy resin had the best resistance to chemical attack, irrespective of the acid type and acid concentration.

Açaí (Euterpe oleracea mart.) e camu-camu (Myrciaria dubia (H.B.K.) Mc Vaugh) possuem ação anti anêmica?

Avaliou-se o impacto da utilização do açaí e camu-camu em pré-escolares de uma Unidade Filantrópica de Manaus-AM. Foram selecionadas 85 crianças voluntárias, de dois a seis anos incompletos, de ambos os sexos, distribuídas aleatoriamente em 5 grupos, tendo como fonte de ferro e vitamina C: açaí e açaí + camu-camu, perfazendo um total de 2 mg de ferro e 40 mg de ácido ascórbico, assim como o ferro aminoácido quelato na concentração de 1 e 2 mg de ferro. O ferro foi distribuído diariamente na colação por um período de 120 dias. Na caracterização da anemia considerou-se o ponto de corte de hemoglobina <11g/dL. Os resultados demonstraram que de um universo de 85 crianças 6 (7%) apresentaram um quadro de desnutrição crônica, sendo ao final da intervenção reduzido para 4 (4,7%). O maior impacto da utilização do açaí foi como fonte energética, refletido no ganho de peso significativo das crianças (1,76 kg), mesmo quando adicionado de camu-camu (1,69 kg). Em relação a concentração de hemoglobina, não foi constatada diferença significativa entre as crianças dos diferentes grupos, independente da fonte de ferro: açaí (0,71 g/dL); açaí + camu-camu (0,60 g/dL), Ferro 2 mg (0,88 g/dL); água (0,85 g/ dL) e Ferro 1 mg (0,54 g/dL). Entretanto, a recuperação de crianças anêmicas foi maior no grupo que recebeu ferro aminoácido quelato na concentração de 2 mg de ferro. Conclui-se que o açaí tem um grande potencial como fonte energética e pouca expressividade como fonte de ferro, mesmo adicionado de camu-camu.

Effect of variables on the thickness of an edible coating applied on frozen fish establishment of the concept of safe dipping time

Glazing is a technique used to retard fish deterioration during storage. This work focuses on the study of distinct variables (fish temperature, coating temperature, dipping time) that affect the thickness of edible coatings (water glazing and 1.5% chitosan) applied on frozen fish. Samples of frozen Atlantic salmon (Salmo salar) at -15, -20, and -25 °C were either glazed with water at 0.5, 1.5 or 2.5 °C or coated with 1.5% chitosan solution at 2.5, 5 or 8 °C, by dipping during 10 to 60 s. For both water and chitosan coatings, lowering the salmon and coating solution temperatures resulted in an increase of coating thickness. At the same conditions, higher thickness values were obtained when using chitosan (max. thickness of 1.41±0.05 mm) compared to water (max. thickness of 0.84±0.03 mm). Freezing temperature and crystallization heat were found to be lower for 1.5% chitosan solution than for water, thus favoring phase change. Salmon temperature profiles allowed determining, for different dipping conditions, whether the salmon temperature was within food safety standards to prevent the growth of pathogenic microorganisms. The concept of safe dipping time is proposed to define how long a frozen product can be dipped into a solution without the temperature raising to a point where it can constitute a hazard.

Assessment of a protease inhibitor peptide for anti-ageing

Ageing and skin exposure to UV radiation induces production and activation of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE). These enzymes are known to break down the extracellular matrix (ECM) which leads to wrinkle formation. Here, we demonstrated the potential of a solid-in-oil nanodispersion containing a competitive inhibitor peptide of HNE mixed with hyaluronic acid (HA), displaying 158 nm of mean diameter, to protect the skin against the ageing effects. Western blot analysis demonstrated that activation of MMP-1 in fibroblasts by HNE treatment is inhibited by the solid-in-oil nanodispersion containing the peptide and HA. The results clearly demonstrate that solid-in-oil nanodispersion containing the HNE inhibitor peptide is a promising strategy for anti-ageing effects. This effect can be seen particularly by ECM regulation by affecting fibroblasts. The formulation also enhances the formation of thicker bundles of actin filaments.

Postharvest shelf life extension of blueberries using a chitosan-based edible coating containing aloe vera juice

Poster

In vitro anti-Candida activity of Glycyrrhiza glabra L.

The severity and frequency of opportunistic fungal infections still growing, concomitantly to the increasing rates of antimicrobial drugs resistance. Natural matrices have been used over years due to its multitude of health benefits, including antifungal potential. Thus, the present work aims to evaluate the anti-Candida potential of the phenolic extract and individual phenolic compounds of Glycyrrhiza glabra L. (licorice), by disc diffusion assay, followed by determination of the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for both planktonic cells and biofilms. Licorice extract evidenced inhibitory potential against the nineteen tested Candida strains, but no pronounced effect was observed by testing the most abundant individual phenolic compounds. Candida tropicalis strains were the most sensible, followed by Candida glabrata, Candida parapsilosis and, then, Candida albicans. Lower MIC and MFC values were achieved to C. glabrata and C. tropicalis, which confirms its susceptibility to licorice extract; however, for C. tropicalis strains a higher variability was observed. Anti-biofilm potential was also achieved, being most evident in some C. glabrata and C. tropicalis strains. In general, a twice concentration of the MIC was necessary for planktonic cells to obtain a similar potential to that one observed for biofilms. Thus, an upcoming approach for new antifungal agents, more effective and safer than the current ones, is stablished; notwithstanding, further studies are necessary in order to understand its mechanism of action, as also to assess kinetic parameters.

Impact of an educational hands-on project on the antimicrobial, antitumor and anti-inflammatory properties of plants on Portuguese students' awareness, knowledge, and competences

Promoting environmental and health education is crucial to allow students to make conscious decisions based on scientific criteria. The study is based on the outcomes of an Educational Project implemented with Portuguese students and consisted of several activities, exploring pre-existent Scientific Gardens at the School, aiming to investigate the antibacterial, antitumor and anti-inflammatory properties of plant extracts, with posterior incorporation in soaps and creams. A logo and a webpage were also created. The effectiveness of the project was assessed via the application of a questionnaire (pre- and post-test) and observations of the participants in terms of engagement and interaction with all individuals involved in the project. This project increased the knowledge about autochthonous plants and the potential medical properties of the corresponding plant extracts and increased the awareness about the correct design of scientific experiments and the importance of the use of experimental models of disease. The students regarded their experiences as exciting and valuable and believed that the project helped to improve their understanding and increase their interest in these subjects and in science in general. This study emphasizes the importance of raising students’ awareness on the valorization of autochthonous plants and exploitation of their medicinal properties.

Evaluation of antinociceptive and anti-inflammatory activities of the topical preparation of Cipura paludosa (Iridaceae)

Alho do mato (Cipura paludosa, Iridaceae) is a medicinal plant found in the Amazon rain forest, North of Brazil. It has been used to treat algic, inflammatory and infectious processes. The aim of this study was to evaluate the anti-inflammatory and antinociceptive action of the crude Cipura paludosa ethanolic extract at concentrations ranging between 2.0 and 4.0% in Oil and Water cream formulations for topical use. The physical-chemical stability of the formulations was monitored over a six-month period with the use of accelerated stability tests. In order to evaluate the anti-inflammatory and antinociceptive activities, we used a paw edema test induced by carrageenan and a formalin test, respectively. The paw edema test showed that there was a statistical difference in the control group in relation to the treatments. The formalin test did not confirm antinociceptive action of the treatments with the extract in the early phase of the test. However, statistical difference was confirmed for the treatments in relation to the control in the late phase. The antinociceptive and anti-inflammatory activities of Cipura paludosa preparations, as demonstrated in the results, at least partially support the ethno-medical uses of this plant.

Hot-dip galvanized steel dip-coatedwith ureasilicate hybrid in simulated concrete pore solution: Assessment of coating morphology and corrosion protection efficiency

The barrier effect and the performance of an organic–inorganic hybrid (OIH) sol–gel coating are highlydependent on the coating deposition method as well as processing conditions. In this work, studies onthe influence of experimental parameters using the dip coating method were performed. Factors suchas residence time (Rt), a curing step between each dip step and the number of layers of sol–gel OIHfilms deposited on HDGS to prevent corrosion in highly alkaline environments were studied. These OIHcoatings were obtained using a functionalized siloxane, 3-isociantepropyltriethoxysilane that reactedwith a diamino-functionalized oligopolymer (Jeffamine®D-230). The barrier efficiency of OIH coatings insimulated concrete pore solutions (SCPS) was assessed in the first moments of contact, by electrochemicalimpedance spectroscopy and potentiodynamic methods. The durability and stability of the OIH coatings inSCPS was monitored during eight days by macrocell current density. The morphological characterizationof the surface was performed by scanning electronic microscopy before and after exposure to SCPS.Glow discharge optical emission spectroscopy was used to obtain quantitative composition profiles toinvestigate the thickness of the OIH coatings as a function of the number of layers deposited and theinfluence of the Rt in the coating thickness.

The contribution of phenolic acids to the anti-inflammatory activity of mushrooms: Screening in phenolic extracts, individual parent molecules and synthesized glucuronated and methylated derivatives

In the present study, the ethanolic extracts of fourteen edible mushrooms were investigated for their anti-inflammatory potential in LPS (lipopolysaccharide) activated RAW 264.7 macrophages. Furthermore the extracts were chemically characterized in terms of phenolic acids and related compounds. The identified molecules (p-hydroxybenzoic, p-coumaric and cinnamic acids) and their glucuronated and methylated derivatives obtained by chemical synthesis were also evaluated for the same bioactivity, in order to establish structure-activity relationships and to comprehend the effects of in vivo metabolism reactions in the activity of the compounds. The extracts of Pleurotus ostreatus, Macrolepiota procera, Boletus impolitus and Agaricus bisporus revealed the strongest anti-inflammatory potential (EC50 values 96 ± 1 to 190 ± 6 µg/mL, and also the highest concentration of cinnamic acid (656 to 156 µg/g), which was also the individual compound with the highest anti-inflammatory activity. The derivatives of p-coumaric acid revealed the strongest properties, specially the derivative methylated in the carboxylic group (CoA-M1) that exhibited similar activity to the one showed by dexamethaxone used as anti-inflammatory standard; by contrast, the derivatives of p-hydroxybenzoic revealed the lowest inhibition of NO production. All in all, whereas the conjugation reactions change the chemical structure of phenolic acids and may increase or decrease their activity, the glucuronated and methylated derivatives of the studied compounds are still displaying anti-inflammatory activity.

Effect of chitosan-Aloe vera coating on postharvest quality of blueberry (Vaccinium corymbosum) fruit

The present study was carried out to evaluate the effect of chitosan-based edible coatings with Aloe vera extract on the postharvest blueberry fruit quality during storage at 5 °C. Firstly, A. vera fractions (pulp and liquid) were extracted from leaves and evaluated in terms of antifungal and antioxidant capacities. The choice of the most adequate chitosan and A. vera fraction concentrations to be incorporated in coating formulation was made based on the wettability of the corresponding coating solutions. Coatings with 0.5% (w/v) chitosan + 0.5% (w/v) glycerol + 0.1% (w/v) Tween 80 + 0.5% (v/v) A. vera liquid fraction presented the best characteristics to uniformly coat blueberry surface. Physico-chemical (i.e., titratable acidity, pH, weight loss) and microbiological analyses of coated blueberries (non-inoculated or artificially inoculated with Botrytis cinerea) were performed during 25 d. Microbiological growth and water loss levels were approximately reduced by 50% and 42%, respectively, in coated blueberries after 25 d compared to uncoated blueberries. After 15 d, weight loss values were 6.2% and 3.7% for uncoated and chitosanA. vera coated blueberries, respectively. Uncoated fruits presented mold contamination after 2 d of storage (2.0 ± 0.32 log CFU g1), whilst fruits with chitosan-based coatings with A. vera presented mold contamination only after 9 d of storage (1.3 ± 0.35 log CFU g1). Overall, coatings developed in this study extend blueberries shelf-life for about 5 d, demonstrating for the first time that the combination of chitosan and A. vera liquid fraction as edible coating materials has great potential in expanding the shelf-life of fruits.

Escritas da utopia na literatura contemporânea – da utopia à distopia

Tese de Doutoramento em Ciências da Literatura (Especialidade em Literatura Comparada)