Browsing by Author "Castro, Matilde"
Now showing 1 - 9 of 9
Results Per Page
Sort Options
- Antibioterapia local para tratamento de infecções em implantes ortopédicosPublication . Bettencourt, Ana; Duarte, Aida; Pinto, Pedro; Castro, Matilde; Monteiro, JacintoAntibioterapia local para tratamento de infecções ortopédicas.
- Evaluation of cytotoxicity and oxidative stress induced by acrylic bone cement in raw 264.7 macrophagesPublication . Bettencourt, Ana F.; Fernandes, Ana S.; Oliveira, Nuno G.; Monteiro, Jacinto; Calado, Antonio; Castro, Matilde
- Evaluation of the protective effect of MnTMPyP on the cytotoxicity induced by different oxidant agentsPublication . Fernandes, Ana Sofia; Gaspar, Jorge; Cabral, M. Fatima; Bettencourt, Ana F.; Caneiras, Catla; Rueff, Jose; Castro, Matilde; Costa, Judite; Oliveira, Nuno G.
- Lipid composition and nutritional value of some meats with Protected Designation of Origin (PDO)Publication . Prates, José A. M.; Ribeiro, Verónica; Quaresma, Mário; Lourenço, Marta; Martins, Susana; Alves, Susana; Portugal, Ana; Castro, Matilde; Fontes, Carlos M. G.; Bessa, Rui J. B.; Alfaia, Cristina M.The aim of this work was to characterise and compare the lipid cQmposition (lípid and eholcsterol contents, fatty acid composition and conjugated linoleie acid isomers) and nutritiona! value (PUFA/SFA and n-6/n-3 ratios) of four Portuguese mea!s with Protceted Designation of Origin (POO; Camalentejana-PDO beel: Mertolenga-POO beef, Barrosã-POO veal and Arouquesa-POO veal), in 1\\'0 distinct slaughter seasoos (early autUnm and late spring). The purebred bovines were maintained according to the traditional productioo systems following the rules established in the meat-POO product specificatioos. ln addition, we also compared the nutritional qU31ityof illtramuscular fat in thesc meats-PDO ,vith the meat obtained from AlentejanaxCharolais erossbrcd young bulls produced io a typical intcnsive concentrate-based system. The results obtained for Carnalentejana-PDO beef (Meat Science. 2006. 72, 425-436), Mertolenga-PDO bcef (Joumal of lhe Science of Food and Agrieulture, 2006, 86, 2196-2205), Barrosã-PDO veal (Food Chemistry, 2006, 94,469-477; Meat Science, 2007, 75,44-52) and Arouquesa-PDO veal (Meat Science, submitted), indicate that intramuscular tàts of meats-PDO. as a result of the beneficial grass effects 00 the eharacterislics of meat lipids, are of grcater nutritional quality than inteosively produêcd bcef from crossbred young bulls throughout the year. However, the data suggest that beef-PDO (Camalentejana-POO aod Mertolenga-POO) iotramuseular falorelative 10Ihat fram veal-PDO (Barrosã-PDO veal and Arouquesa-PDO veal), depiets a 1m.vnutritional ql,lality throughout the year. These differences may be explained by the finishing period of Alentejana and Mertolenga purebrcd young bulls 011coneentrate, which attenuates the beneficia] effects on the charaeteristies ofmeat fat associated with grass intake
- Macrocyclic copper(II) complexesPublication . Fernandes, Ana S.; Gaspar, Jorge; Cabral, M. Fatima; Caneiras, Catia; Guedes, Rita; Rueff, Jose; Castro, Matilde; Costa, Judite; Oliveira, Nuno G.Synthetic superoxide dismutase mimetics have emerged as a potential novel class of drugs for the treatment of oxidative stress related diseases. Among these agents, metal complexes with macrocyclic ligands constitute an important group. In this work we synthesized five macrocyclic copper(II) complexes and evaluated their ability to scavenge the superoxide anions generated by the xanthine-xanthine oxidase system. Two different endpoints were used, the nitro blue tetrazolium (NBT) reduction assay (colorimetric method) and the dihydroethidium (DHE) oxidation assay (fluorimetric method). IC50 values in the low micromolar range were found in four out of five macrocyclic complexes studied, demonstrating their effective ability to scavenge the superoxide anion. The IC50 values obtained with the NBT assay for the macrocyclic copper(II) complexes, were consistently higher, approximately threefold, than those obtained with the DHE assay. Spectroscopic and electrochemical studies were performed in order to correlate the structural features of the complexes with their superoxide scavenger activity. Cytotoxicity assays were also performed using the MTT method in V79 mammalian cells and we found that the complexes, in the range of concentrations tested in the superoxide scavenging assays were not considerably toxic. In summary, some of the presented macrocyclic copper(II) complexes, specially those with a high stability constant and low IC50 appear to be promising superoxide scavenger agents, and should be considered for further biological assays. (c) 2007 Elsevier Inc. All rights reserved.
- Novel copper(II) macrocyclic complexes with superoxide scavenging activityPublication . Fernandes, Ana Sofia; Cabral, M. Fatima; Rueff, Jose; Caneiras, Catia; Gaspar, Jorge; Castro, Matilde; Costa, Judite; Oliveira, Nuno G.
- Oxidative injury in V79 Chinese hamster cells: protectivePublication . Fernandes, Ana S.; Serejo, João; Gaspar, Jorge; Cabral, Fátima; Bettencourt, Ana F.; Rueff, José; Castro, Matilde; Costa, Judite; Oliveira, Nuno G.Oxidative cell injury could be induced by different reactive oxygen species (ROS) operating in multiple pathways. The present work is focused on three different models of oxidative stress: the xanthine/xanthine oxidase system (XXO), an extracellular superoxide anion generator; tert-butylhydroperoxide (TBHP), an analogue of lipid hydroperoxides; and doxorubicin (Dox), an anticancer drug. Superoxide and peroxyl radicals, among other ROS, could be effectively scavenged by MnTM-4-PyP, a polyfunctional catalytic antioxidant. In this report, we have addressed the role of MnTM-4-PyP on the protection against the cytotoxicity induced by the three aforementioned oxidants. The effect of MnTM-4-PyP (0.1–100 μM) was evaluated in V79 fibroblasts using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide reduction and the crystal violet assays, as well as the mitotic index. Also, the generation of intracellular ROS was studied by the fluorescent probe dihydroethidium. MnTM-4-PyP has shown significant protective effects against the cytotoxicity of XXO and TBHP, increasing the cell viability in approximately 40% and reducing the intracellular level of ROS. However, no considerable protection occurred against Dox. The three oxidants caused a mitotic index reduction that was not altered by MnTM-4-PyP. In summary, MnTM-4-PyP appears to be a promising agent for the protection against oxidative injury. However, it has shown differential responses, reinforcing the need to study different experimental models for the adequate evaluation of its potentialities as a catalytic antioxidant.
- Pyridine-containing macrocyclic copper(II) complexesPublication . Fernandes, Ana S.; Oliveira, Nuno G.; Gaspar, Jorge; Cabral, M. Fatima; Caneiras, Catia; Rueff, Jose; Castro, Matilde; Costa, Judite
- Total and organic mercury, selenium and alpha-tocopherol in some deep-water fish speciesPublication . Afonso, Claudia; Lourenco, Helena M.; Pereira, Catia; Martins, Maria F.; Carvalho, Maria L.; Castro, Matilde; Nunes, Maria L.BACKGROUND: Mercury is a well-known toxic element present in seafood. Nevertheless some antioxidants, like selenium, as an integral component of the enzyme glutathione peroxidase, and alpha-tocopherol having a protective role against it, are present as well. The purpose of this study was to evaluate the levels of total mercury (Hg-T), organic mercury (Hg-Org), Se and alpha-tocopherol in some adult deep-water fish species caught off Portuguese waters. RESULTS: Levels of Hg-T were above EU limits in 6% of Lophius spp. and Aphanopus carbo, 2% ofLepidorhombus spp. and 70% of Helicolenus dactylopterus. Hg-Org represented the major fraction (more than 84%) of Hg-T in all studied muscles. The selenium concentration in muscle was similar in all species (about 0.4 mg kg(-1) wet weight) and the highest level of alpha-tocopherol (70 mg kg(-1) wet weight) was found in Aphanopus carbo. CONCLUSION: The muscle of all species studied is a good source of selenium, but only can give a small contribution of alpha-tocopherol. Attending to the provisional tolerable weekly intake established by the WHO/FAO for methylmercury, it appears that the species studied should be consumed sparingly. (c) 2008 Society of Chemical Industry. - QCA III - PO MARE [22-05-01- FDR-0006]. - The authors thank the financial support from QCA III - PO MARE "Valorizacao e Inovacao em Produtos da Pesca - 22-05-01- FDR-0006 - Vigilancia, Seguran a e Qualidade Alimentar" project and to Dr Narcisa Bandarra, Vanessa Ferraria and Patricia Anacleto for the technical support in the determination of selenium and a-tocopherol. The authors also thank the scientists of the U-REMS of the INRB-IP/IPIMAR, who supplied the fish and gave advice on the biological parameters.