58 research outputs found

    A 10-Year Retrospective Analysis of Methyl Aminolevulinate Photodynamic Therapy Consultation at the Hospital de Braga

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    Photodynamic therapy (PDT) is a well-established treatment for actinic keratosis (AK), basal cell carcinoma (BCC), and Bowen's disease (BD). The object of this study was to describe the results of a retrospective analysis of patients treated with methyl aminolevulinate PDT (MAL-PDT) with red light, over the past decade at the Hospital de Braga (Braga, Portugal)

    On the electropolishing and anodic oxidation of Ti-15Mo alloy

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    This paper presents research on modifying the surface of Ti-15Mo alloy using electropolishing and anodic passivation. The electropolishing process was carried out in solutions containing sulfuric acid, ethylene glycol, ammonium fluoride and oxalic acid. Whereas a voltage range from 20 to 100 V and a 1 M orthophosphoric acid solution were used during the anodic passivation. The influence of above mentioned processes parameters on the quality of the obtained oxide layer on Ti-15Mo alloy was investigated. The analysis of Ti-15Mo surface after modification was performed using scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), ellipsometry, and mechanical tests. Moreover, the corrosion resistance was investigated using a potentiostatic method in Ringer's solution. It was found that electropolishing leads to an increase in the surface homogeneity and to the form of an oxide layer, which consisted of TiO2 and MoO3. Whereas the oxide layers obtained during anodic passivation were characterized by different properties depending on the applied voltage. The anodic passivation at various voltages (20-100 V) increased the surface wettability (94.5°-87.6°) in comparison to the electropolished sample (97.5°). Moreover, the obtained oxide layer after anodization exhibited a high hardness. The electrolytic polishing and anodic passivation of Ti-15Mo also improved corrosion resistance of the alloy in contact with Ringer's solution. The sample anodized at 80 V presented the highest corrosion resistance by the smallest corrosion current density (1.4 nA cm-2) and the highest polarization resistance (37.4 MΩ cm2). © 2016 Elsevier Ltd. All rights reserved

    Timing the multiple cell death pathways initiated by Rose Bengal acetate photodynamic therapy

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    Rose Bengal acetate photodynamic therapy (RBAc–PDT) induced multiple cell death pathways in HeLa cells through ROS and ER stress. Indeed, apoptosis was the first preferred mechanism of death, and it was triggered by at least four different pathways, whose independent temporal activation ensures cell killing when one or several of the pathways are inactivated. Apoptosis occurred as early as 1 h after PDT through activation of intrinsic pathways, followed by activation of extrinsic, caspase-12-dependent and caspase-independent pathways, and by autophagy. The onset of the different apoptotic pathways and autophagy, that in our system had a pro-death role, was timed by determining the levels of caspases 9, 8, 3 and 12; Bcl-2 family; Hsp70; LC3B; GRP78 and phospho-eIF2α proteins. Interestingly, inhibition of one pathway, that is, caspase-9 (Z-LEHD-FMK), caspase-8 (Z-IETD-FMK), pan-caspases (Z-VAD-FMK), autophagy (3-MA) and necrosis (Nec-1), did not impair the activation of the others, suggesting that the independent onset of the different apoptotic pathways and autophagy did not occur in a subordinated manner. Altogether, our data indicate RBAc as a powerful photosensitiser that induces a prolonged cytotoxicity and time-related cell death onset by signals originating from or converging on almost all intracellular organelles. The fact that cancer cells can die through different mechanisms is a relevant clue in the choice and design of anticancer PDT

    Electrochemical Characterization of Ca₆₅Mg₁₅Zn₂₀ Amorphous Alloy in Selected Physiological Fluids

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    The corrosion behavior of the bulk glassy samples of Ca₆₅Mg₁₅Zn₂₀ alloy was studied by electrochemical measurements and immersion tests in a simulated body fluid, physiological fluid, and the Ringer solution. The results of immersion show that the volume of H₂ evolved after 2 h in simulated body fluid (29.8 ml/cm²) is the highest in comparison with the results of measurements conducted in physiological fluid (11.3 ml/cm²) and the Ringer solution (7.4 ml/cm²). The electrochemical measurements indicated a shift of the corrosion potential (E_{corr}) from -1.58 V for plate tested in a physiological fluid to -1.56 V and -1.54 V for samples immersed in the Ringer solution and simulated body fluid, adequately. The X-ray diffraction measurements were used to determine composition of corrosion products. The corrosion products were mainly identified to be calcium carbonates and calcium/magnesium hydroxides

    Magnetic properties and structure after crystallization of Fe80-xB20Nbx (x = 4, 6, 10) metallic glasses

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    The ferromagnetic Fe-based amorphous alloys were studied due to properties for soft magnetic applications. Depending on different Nb addition, the formation of crystalline phases after annealing of amorphous Fe80xB20Nbx (x = 4, 6, 10) alloys was studied. The crystallization products as well as the phase structure were determined using the Mössbauer spectrometry combined with differential scanning calorimetry and magnetic measurements. The addition of Nb caused a shift of crystallization process towards higher temperatures and induced changes in coercive force and decreased the saturation magnetization. It was found that Nb addition changed the crystallization process from single crystallization for Fe76B20Nb4 alloy to binary crystallization in the Fe74B20Nb6 and Fe70B20Nb10 glasses. The annealing process at the onset crystallization temperature induced complex phase formation including the -Fe, Fe3B, and Fe2B phases for alloys x = 4, 6[…
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