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Quinta do Anjo, Portugal

Aguilera F.-S.,University of Granada | Osorio R.,University of Granada | Osorio E.,University of Granada | Moura P.,Campus Universitario Quinta da Granja | Toledano M.,University of Granada
Medicina Oral, Patologia Oral y Cirugia Bucal | Year: 2012

Objectives: to evaluate the effect of sodium hypochlorite (NaOCl) treatment on dentin bonding by means of shear bond strength (SBS) measurements when using Prime&Bond NT (PB NT) adhesive. Ultrastructure of the interfaces was examined by scanning electron microscopy (SEM). Study design: Extracted human third molars were sectioned and ground to expose flat surfaces of superficial or deep dentin. Specimens were randomly assigned to two equal groups, and bonded as follows: (1) according to the manufacturers' directions, after 35% H3PO4 etching, (2) 5% NaOCl treated for 2 minutes, after 35% H3PO4 etching. Each sample was embedded in a Watanabe shear test assembly for a single plane lap shear. After PB NT bonding, specimens were stored in water for 24 h at 37°C and thermocycled (500x). Samples were tested in shear to failure using a universal testing machine at 0.75 mm/ min. Data were analyzed with ANOVA and Newman-Keuls multiple comparison test procedures. Two samples of each group were randomly selected to investigate the morphologic aspect of the resin/dentin interface with SEM. Results: After etching and after aqueous sodium hypochlorite (NaOClaq) application, SBS values were similar on superficial than deep dentin (p>0.05). SEM findings shows for H3PO4 etching conditioned samples a detectable hybrid layer and long resin tags; for NaOCl treated specimens, it may be observed a non apparent hybrid layer, and the adhesive contact directly with the neck of the cylindrical resin tags. Conclusions: The use of 5% NaOCl for 2 min after dentin demineralization when PB NT was employed did not improve the bond strength to dentin, probably due to nanofiller content and/or oxidative changes on collagen-depleted dentin. © Medicina Oral S. L. Source


Aguilera F.S.,University of Granada | Osorio R.,University of Granada | Osorio E.,University of Granada | Moura P.,Campus Universitario Quinta da Granja | Toledano M.,University of Granada
Medicina Oral, Patologia Oral y Cirugia Bucal | Year: 2012

Objectives: to evaluate the effect of sodium hypochlorite (NaOCl) treatment on surface dentin roughness (Ra) and contact angle (CA) when using Prime&Bond NT adhesive (PB NT). Study Design: Extracted human third molars were sectioned to expose fat, superficial and deep dentin surfaces. CA and Ra were measured (1) before and (2) after 35% H3PO4 etching, and (3) H3PO4 etching + 5% NaOCl treated for 2 minutes before the application of PB NT. CA was measured by the Axisymmetric Drop Shape Analysis Technique using distilled and deionized water and PB NT. Roughness was evaluated with a profilometer, twelve radial measurements were performed in each treatment surface. Data were analyzed with two-way ANOVA and Newman-Keuls multiple comparison test procedures. Results: CA values decreased after acid etching and even more after NaOCl treatment on deep dentin when water was tested. With resin, there were not differences on CA results after H3PO4 neither after NaOCl treatment, in both dentin surfaces. Etching and NaOCl treatment resulted in surface roughness increase. Conclusions: In spite of the higher roughness after NaOCl treatment on superficial and deep dentin, the use of 5% NaOCl for 2 min after dentin demineralization when PB NT was employed did not improved the wettability of dentin, probably due to nanofiller content and/or hydrogen-bonding interactions with residues of the organic matrix on collagen-depleted dentin. © Medicina Oral S. L. Source


Lee C.J.J.,University of Toronto | Goncalves L.L.,University of Toronto | Goncalves L.L.,Campus Universitario Quinta da Granja | Wells P.G.,University of Toronto
FASEB Journal | Year: 2011

Thalidomide (TD) causes birth defects in humans and rabbits via several potential mechanisms, including bioactivation by embryonic prostaglandin H synthase (PHS) enzymes to a reactive intermediate that enhances reactive oxygen species (ROS) formation. We show herein that TD in rabbit embryo culture produces relevant embryopathies, including decreases in head/brain development by 28% and limb bud growth by 71% (P<0.05). Two TD hydrolysis products, 2-phthalimidoglutaramic acid (PGMA) and 2-phthalimidoglutaric acid (PGA), were similarly embryopathic, attenuating otic vesicle (ear) and limb bud formation by up to 36 and 77%, respectively (P<0.05). TD, PGMA, and PGA all increased embryonic DNA oxidation measured as 8-oxoguanine (8-oxoG) by up to 2-fold (P<0.05). Co- or pretreatment with the PHS inhibitors eicosatetraynoic acid (ETYA) or acetylsalicylic acid (ASA), or the free-radical spin trap phenylbutylnitrone (PBN), completely blocked embryonic 8-oxoG formation and/or embryopathies initiated by TD, PGMA, and PGA. This is the first demonstration of limb bud embryopathies initiated by TD, as well as its hydrolysis products, in a mammalian embryo culture model of a species susceptible to TD in vivo, indicating that all likely contribute to TD teratogenicity in vivo, in part through PHS-dependent, ROS-mediated mechanisms.-Lee, C. J. J., Gonçalves, L. L., Wells, P. G. Embryopathic effects of thalidomide and its hydrolysis products in rabbit embryo culture: evidence for a prostaglandin H synthase (PHS)-dependent, reactive oxygen species (ROS)-mediated mechanism. © FASEB. Source


Couceiro J.,Instituto Superior Of Ciencias Da Saude Egas Moniz | Couceiro J.,Campus Universitario Quinta da Granja | Bandarra S.,Instituto Superior Of Ciencias Da Saude Egas Moniz | Sultan H.,Instituto Superior Of Ciencias Da Saude Egas Moniz | And 4 more authors.
Forensic Science International | Year: 2016

The emergence and abuse of synthetic cannabinoids has been increasing as an alternative to cannabis, mainly among youth. As their appearance on the drug market has been recent, the pharmacological and toxicological profiles of these psychoactive substances are poorly understood. Current studies suggest that they have stronger effects compared to their natural alternatives and their metabolites retain affinity towards CB1 receptors in CNS. Since studies on its toxicological properties are scarce, the effects of the drug in human derived cell lines were investigated. The present study was designed to explore the toxicological impact of parent drug versus phase I metabolites of synthetic cannabinoids on human cells with and without CB1 receptor. The human cell line of neuroblastoma SH-SY5Y and human kidney cell line HEK-293T were exposed to JWH-018 and to its N-(3-hydroxypentyl) metabolite. Cell toxicity was evaluated using the MTT and LDH assay. Additionally, a dual staining methodology with fluorescent Annexin V-FITC and propidium iodide was performed to address the question of whether JWH-018 N-(3-hydroxypentyl) metabolite is inducing cell death through apoptosis or necrosis, in HEK293T and SH-SY5Y cell lines. The obtained results show that JWH-018 does not cause a statistically significant decrease in cell viability, in contrast to its N-(3-hydroxypentyl) metabolite, which at ≥ 25 μM causes a significant decrease in cell viability. Both cell lines are affected by JWH-018 metabolite. Our results point to higher toxicity of JWH-018 metabolite when compared to its parent drug, suggesting a non-CB1 receptor mediated toxicological mechanism. Comparing the results from Annexin V/PI with MTT and LDH assays of SH-SY5Y and HEK293T in the presence of the synthetic cannabinoid metabolite, emerges the picture that cellular viability decreases and associated death is occurring through necrosis. © 2016 Elsevier Ireland Ltd. Source


Branco P.,National Laboratory of Energy and Geology | Francisco D.,National Laboratory of Energy and Geology | Chambon C.,French National Institute for Agricultural Research | Hebraud M.,French National Institute for Agricultural Research | And 4 more authors.
Applied Microbiology and Biotechnology | Year: 2014

Saccharomyces cerevisiae plays a primordial role in alcoholic fermentation and has a vast worldwide application in the production of fuel-ethanol, food and beverages. The dominance of S. cerevisiae over other microbial species during alcoholic fermentations has been traditionally ascribed to its higher ethanol tolerance. However, recent studies suggested that other phenomena, such as microbial interactions mediated by killer-like toxins, might play an important role. Here we show that S. cerevisiae secretes antimicrobial peptides (AMPs) during alcoholic fermentation that are active against a wide variety of wine-related yeasts (e.g. Dekkera bruxellensis) and bacteria (e.g. Oenococcus oeni). Mass spectrometry analyses revealed that these AMPs correspond to fragments of the S. cerevisiae glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein. The involvement of GAPDH-derived peptides in wine microbial interactions was further sustained by results obtained in mixed cultures performed with S. cerevisiae single mutants deleted in each of the GAPDH codifying genes (TDH1-3) and also with a S. cerevisiae mutant deleted in the YCA1 gene, which codifies the apoptosis-involved enzyme metacaspase. These findings are discussed in the context of wine microbial interactions, biopreservation potential and the role of GAPDH in the defence system of S. cerevisiae. © 2013 Springer-Verlag Berlin Heidelberg. Source

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