367 research outputs found

    Liposomal formulations for rheumatoid arthritis

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    Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Rheumatoid arthritis (RA) is the most common inflammatory rheumatic disease, affecting almost 1% of the world population. Although the cause of RA remains unknown, the complex interaction between immune mediators (cytokines and effector cells) is responsible for the joint damage that begins at the synovial membrane. Activated macrophages are critical in the pathogenesis of RA and showed specifically express a receptor for the vitamin folic acid (FA), folate receptor β (FRβ). This particular receptor allows internalization of FA-coupled cargo. [...]info:eu-repo/semantics/publishedVersio

    Robustness of corroded reinforced concrete structures. A structural performance approach

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    Structure and Infrastructure Engineering, 1-17The aim of this work is to provide new contributions in order to define more accurately the structural robustness concept, particularly when applied to corroded reinforced concrete (RC) structures. To fulfill such task, several robustness indicators are analyzed and discussed with special emphasis on structural performance based measures. A new robustness definition and a framework to assess it are then proposed, based on the structural performance lost after damage occurrence. The competence of the proposed methodology is then tested comparing the robustness of two reinforced concrete foot bridges under corrosion. The damage considered is the longitudinal reinforcement corrosion level and load carrying capacity is the structural performance evaluated. In order to analyze corrosion effects, a finite element based on a two step analysis is adopted. In the first step a cross section analysis is performed to capture phenomenons such as expansion of the reinforcement due to the corrosion products accumulation; damage and cracking in the reinforcement surrounding concrete; steel-concrete bond strength degradation; and effective reinforcement area reduction. The results obtained are then used to build a 2D structural model, in order to assess the maximum load carrying capacity of the corroded structure. For each foot bridge, robustness is assessed using the proposed methodology

    Microaerophilic–aerobic sequential decolourization/biodegradation of textile azo dyes by a facultative Klebsiella sp. strain VN-31

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    Four different azo dyes were decolourized and biodegraded in a sequential microaerophilic–aerobic treatment by a facultative Klebsiella sp. strain VN-31, a bacterium isolated from activated sludge process of the textile industry. Dye decolourization was performed under microaerophilic conditions until no colour was observed (decolourization percentage >94%). The medium was then aerated to promote the biodegradation of the amines produced. The presence of aromatic amine in the microaerophilic stage and its absence in the aerobic stage demonstrate azo bond reduction and an oxidative biodegradation process, respectively. Total Organic Carbon (TOC) reduction for the growth medium plus dyes was ∼50% in the microaerophilic stage and ∼80% in the aerobic stage. The degradation products were also characterized by FT-IR and UV–vis techniques and their toxicity measured using Daphnia magna. The results provide evidence that the successive microaerophilic/aerobic stages, using a single Klebsiella sp. strain VN-31 in the same bioreactor, were able to form aromatic amines by the reductive break down of the azo bond and to oxidize them into non-toxic metabolites.The authors would like to thank the Portuguese Foundation of Science and Technology (FCT) for providing the grant to Andrea Zille (SFRH/BPD/24238/2005) and the Brazilian Foundations for the Coordination of Training Graduated Pessoal of the Ministry of Education (CAPES) and the National Counsel for Technological and Scientific Development (CNPq) for providing the grant to Elisangela Franciscon

    Biodegradation of textile azo dyes by a facultative Staphylococcus arlettae strain VN-11 using a sequential microaerophilic/aerobic process

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    A facultative Staphylococcus arlettae bacterium, isolated from an activated sludge process in a textile industry, was able to successfully decolourize four different azo dyes under microaerophilic conditions (decolourization percentage >97%). Further aeration of the decolourized effluent was performed to promote oxidation of the degradation products. The degradation products were characterized by FT-IR and UV–vis techniques and their toxicity with respect to Daphnia magna was measured. The amine concentrations as well as the total organic carbon (TOC) levels were monitored during the biodegradation process. The presence of aromatic amine in the microaerophilic stage and its absence in the aerobic stage indicated the presence of azoreductase activity and an oxidative biodegradation process, respectively. TOC reduction was ∼15% in the microaerophilic stage and ∼70% in the aerobic stage. The results provided evidence that, using a single Staphylococcus arlettae strain in the same bioreactor, the sequential microaerophilic/aerobic stages were able to form aromatic amines by reductive break-down of the azo bond and to oxidize them into non-toxic metabolites.The authors would like to thank the Portuguese Foundation of Science and Technology (FCT) for providing the grant to Andrea Zille (SFRH/BPD/24238/2005), and the Brazilian Foundation for the Coordination of the Improvement of University Graduates of the Ministry of Education (CAPES) and the National Research Counsel (CNPq) for providing the grants to Elisangela Franciscon

    Production and characterization of Orpinomyces mutant xylanases with improved temperature and pH stabilities

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    The error-prone PCR technique has been widely used in order to obtain thermostable enzymes more suitable for industrial conditions. The Orpinomyces xynA mutant library allowed the selection of four thermostable mutants (M1-M4). Molecular dynamics (MD) predicted an N-terminal tail as being a destabilizing structural region and allowed further enhancing of the mutant xylanases thermostability. Thus, removal of the 27 amino acid residues enabled an increase in the enzyme half-life values (t1/2). However, besides the improved thermostability, the large enzyme production and high catalytic performance are also relevant for the biotechnological application of enzymes. During the mutant enzymes production in E. coli, the IPTG induction protocol allowed high expression levels of soluble and active xylanases. The mutant xylanases without the 27 amino acid residues showed improved thermostability and the shorter versions of M2 and M4 (named as SM2 and SM4) also presented a good performance in more extreme pH conditions

    O Índice de Resistência Microcirculação Para o Estudo Invasivo da Microcirculação Coronária. Descrição e Validação de um Modelo Animal

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    INTRODUCTION: The index of microcirculatory resistance (IMR) enables/provides quantitative, invasive, and real-time assessment of coronary microcirculation status. AIMS: The primary aim of this study was to validate the assessment of IMR in a large animal model, and the secondary aim was to compare two doses of intracoronary papaverine, 5 and 10 mg, for induction of maximal hyperemia and its evolution over time. METHODS: Measurements of IMR were performed in eight pigs. Mean distal pressure (Pd) and mean transit time (Tmn) were measured at rest and at maximal hyperemia induced with intracoronary papaverine, 5 and 10 mg, and after 2, 5, 8 and 10 minutes. Disruption of the microcirculation was achieved by selective injection of 40-μm microspheres via a microcatheter in the left anterior descending artery. RESULTS: In each animal 14 IMR measurements were made. There were no differences between the two doses of papaverine regarding Pd response and IMR values - 11 ± 4.5 U with 5 mg and 10.6 ± 3 U with 10 mg (p=0.612). The evolution of IMR over time was also similar with the two doses, with significant differences from resting values disappearing after five minutes of intracoronary papaverine administration. IMR increased with disrupted microcirculation in all animals (41 ± 16 U, p=0.001). CONCLUSIONS: IMR provides invasive and real-time assessment of coronary microcirculation. Disruption of the microvascular bed is associated with a significant increase in IMR. A 5-mg dose of intracoronary papaverine is as effective as a 10-mg dose in inducing maximal hyperemia. After five minutes of papaverine administration there is no significant difference from resting hemodynamic status

    Folic acid-tagged protein nanoemulsions loaded with CORM-2 enhance the survival of mice bearing subcutaneous A20 lymphoma tumors.

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    UNLABELLED: Folic Acid (FA)-tagged protein nanoemulsions were found to be preferentially internalized on B-cell lymphoma cell line (A20 cell line), which, for the first time, is reported to express folate receptor (FR)-alpha. Carbon monoxide releasing molecule-2 (CORM-2) was incorporated in the oil phase of the initial formulation. FA-functionalized nanoemulsions loaded with CORM-2 exhibited a considerable antitumor effect and an increased survival of BALB/c mice bearing subcutaneous A20 lymphoma tumors. The developed nanoemulsions also demonstrated to be well tolerated by these immunocompetent mice. Thus, the results obtained in this study demonstrate that FA-tagged protein nanoemulsions can be successfully used in cancer therapy, with the important ability to delivery drugs intracellularly. FROM THE CLINICAL EDITOR: In this research, the authors developed folic acid tagged nanoemulsions containing a carbon monoxide releasing protein molecule for targeted cancer cell treatment. In-vitro and in-vivo experiments showed efficacy against B-cell lymphoma cells. The same nanocarrier platform could be applied to other tumor cells expressing folate receptors on the cell surface.This is the author accepted manuscript. The final version is avilable via Elsevier at http://www.sciencedirect.com/science/article/pii/S1549963415000726

    Enzymatic surface hydrolysis of PET enhances bonding in PVC coating

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    The effect of polyesterase preparations from Thermomyces lanuginosus and Beauveria brongniartii on the hydrophilicity of PET materials was assessed. As a result of polyesterase treatment the hydrophilicity of PET fabrics was increased by up to 8 cm in terms of rising height with increases in surface tension from 6.2 mNm (heat-inactivated control samples) to above 8 mNm. Both enzymes were able to increase the amount of hydroxyl groups on PET from 90 to a maximum of 182 mmol kg-1, while only the B. brongniartii polyesterase released significant amounts of terephthalic acid from PET. Enzymatic surface hydrolysis of PET increased the bonding strength in PVC coating to 13.40 daN 5cm-1 using 0.5% adhesive compared to 11.5 daN 5cm-1 obtained without enzyme pretreatment and 6% of adhesive.The research was financed by the SFG, the FFG, the city of Graz and the province of Styria and by European Commission within the project GRD 2000-30110 Biosynte

    Polymerization study of the aromatic amines generated by the biodegradation of azo dyes using the laccase enzyme

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    Four different azo dyes were decolorized (color reduction >90%) by bacteria isolated from a textile wastewater effluent. Dye decolorizing was carried out under microaerobic conditions until completion, after which the aromatic amine concentration was determined. A laccase from Myceliophthora thermophila was used to catalyze coupling reactions of the aromatic amines produced from decolorizing the dyes. The reaction was carried out with stirring (100 rpm) in a weak acidic buffer solution (pH 5.0) at 45 °C for 3 days. The presence of aromatic amines in the samples after bacterial decolorizing confirmed the azo bond was reduced in the process. In addition, the UV–vis spectrum was shifted significantly after the sequential bacterial-laccase treatment also indicating a chemical transformation of the dyes. After laccase treatment the solutions formed colored soluble and precipitated products. The particles sizes making up the precipitates formed after laccase treatment varied between 105 and 483 nm as determined by Photon Correlation Spectroscopy (PCS). The laccase treatment also reduced the COD of the dye solutions by ∼20%. We show that successive bacterial-laccase treatment is effective in decolorized azo dyes by reduction of the azo bonds, and promoting coupling reactions between the aromatic amines formed. Promoting coupling reactions between the aromatic amines using enzymes may prove useful for the physical removal and reuse of these amines.The authors would like to thank the Brazilian Foundation Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior of the Ministry of Education (CAPES) and the National Counsel for Technological and Scientific Development (CNPq) for providing grants to Elisangela Franciscon
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