227 research outputs found
Estudo da sinistralidade laboral em meio hospitalar - Aspeto fundamental para a integração da segurança no trabalho na gestão de unidades de saúde
O tipo de atividade profissional e as condições em que é desempenhada constituem fatores determinantes do risco para a saúde dos trabalhadores. Os últimos estudos realizados sobre acidentes de trabalho nas instituições de saúde revelam um aumento da incidência dos acidentes de trabalho com o consequente aumento do absentismo laboral e dos encargos financeiros inerentes.Realizamos um estudo descritivo-correlacional, retrospetivo, compreendendo um período de análise de quatro anos, utilizando os dados do serviço de saúde ocupacional, relatórios anuais e balanços sociais de cada ano em estudo. Os resultados revelaram um aumento progressivo do índice de frequência e do índice de gravidade dos acidentes de trabalho. O maior número de acidentes ocorreu nos enfermeiros, a trabalhar por turnos. A lesão mais declarada é a picada e as mãos o local mais atingido, no entanto são os esforços excessivos e a cervicalgia/lombalgia que produzem uma maior incapacidade para o trabalho com o consequente aumento dos dias de absentismo. Constatamos que o tempo em dias perdido vai gradualmente aumentando ao longo dos 4 anos, assim como as implicações financeiras. Os gestores de topo devem tomar medidas no sentido de garantir uma melhor qualidade de vida dos profissionais, contribuindo para uma melhoria da qualidade da prestação de serviços nas unidades de saúde, preservando os recursos humanos e proporcionando dotações seguras de técnicos de saúde/utente
Nanoscale color control of TiO2 films with embedded Au nanoparticles
Article in pressWe demonstrate an efficient nanoscale control of the optical properties of TiO2 films by tuning the Surface Plasmon Resonance (SPR) in the embedded Au nanoparticles. The films were grown by reactive magnetron
sputtering. SPR tuning was achieved by different annealings, which affected the shape and size of the Au nanoparticles, and also the phase of the dielectric matrix. These changes promoted the variations on the
optical properties. As shown by the modeling of the effective dielectric function of the TiO2/Au in the SPR region, the variation of their optical absorption spectra correlates with morphological changes.Fundação para a Ciência e a Tecnologia (FCT) - PTDC/CTM/70037/2006
Electrochemical vs antibacterial characterization of ZrCN-Ag coatings
Nowadays, antibacterial properties are becoming a viable feature to be introduced in biomaterials due to the possibility of modifying the materials' surface used in medical devices in a micro/nano metric scale. As a result, it is mandatory to understand the mechanisms of the antimicrobial agents currently used and their possible failures. In this work, the antibacterial activity of ZrCNAg films is studied, taking into consideration the ability of silver nanoparticles to be dissolved when embedded into a ceramic matrix. The study focuses on the silver release evaluated by glow discharge optical emission spectroscopy and the effect of the fluid composition on this release. The results revealed a very low silver release of the films, leading to non-antibacterial activity of such materials. The silver release was found to be dependent on the electrolyte composition. NaCl (8.9 g L? 1) showed the lowest spontaneously silver ionization, while introducing the sulfates in Hanks' balanced salt solution (HBSS) such ionization is increased; finally, the proteins incorporated to the (HBSS) showed a reduction of the silver release, which also explains the low ionization in the culture medium (tryptic soy broth) that contains high quantities of proteins.This research is partially sponsored by the FEDER funds through the program COMPETE - Programa Operacional Factores de Competitividade and by the Portuguese national funds through FCT-Fundacao para a Ciencia e a Tecnologia, under the projects ANTIMICROBCOAT - PTDC/CTM/102853/2008 and in the framework of the Strategic Projects PEST-C/FIS/UI607/2011, PEST-C/EME/UI0285/2011 and SFRH/BD/80947/2011.This work has also been supported by the Ministerio de Ciencia e Innovacion of Spain through the Consolider-Ingenio 2010 Programme (CSD2008-00023) and through project RyC2007-0026
Ag-Ti(C,N)-based coatings for biomedical applications : influence of silver content on the structural properties
Ag–TiCN coatings were deposited by dc reactive magnetron sputtering and their structural and
morphological properties were evaluated. Compositional analysis showed the existence of
Ag–TiCN coatings with different Ag/Ti atomic ratios (ranging from 0 to 1.49). The structural
and morphological properties are well correlated with the evolution of Ag/Ti atomic ratio. For
the samples with low Ag/Ti atomic ratio (below 0.20) the coatings crystallize in a B1-NaCl
crystal structure typical of TiC0.3N0.7. The increase in Ag/Ti atomic ratio promoted the
formation of Ag crystalline phases as well as amorphous CNx phases detected in both x-ray
photoelectron spectroscopy and Raman spectroscopy analysis. Simultaneously to the
formation of Ag crystalline phases and amorphous carbon-based phases, a decrease in
TiC0.3N0.7 grain size was observed as well as the densification of coatings.Spanish Ministry of Science and InnovationFundação para a Ciência e Tecnologia (FCT)CRUP InstitutionMCIN
Tuning of the surface plasmon resonance in TiO2/Au thin films grown by magnetron sputtering : the effect of thermal annealing
Nanocomposites consisting of a dielectric matrix, such as TiO2, with embedded noble metal nanoparticles (NPs) possess specific optical properties due to the surface plasmon resonance (SPR) effect, interesting for several applications. The aim of this work is to demonstrate that these properties are sensitive to the nanostructure of magnetron-sputtered TiO2/Au thin films, which can
be tuned by annealing. We study the role of the shape and size distribution of the NPs, as well as the influence of the crystallinity and phase composition of the host matrix on the optical response of the films. All these characteristics can be modified by vacuum annealing treatments of the deposited films. A theoretical interpretation and modeling of the experimental results obtained is presented. The model involves a modified Maxwell-Garnett approach for the effective dielectric
function of the composite (describing the SPR effect) and the transfer matrix formalism for
multilayer optics. Input data are based on the experimental information obtained from the detailed structural characterization of the films. It is shown that the annealing treatments can be used for controlling the optical properties of the composite films, making them attractive for decorative
coatings.Fundação para a Ciência e a Tecnologia (FCT) - PTDC/CTM/70037/200
Ciprofloxacin removal catalysed by conductive carbon materials
Current wastewater treatment technologies are not effective in the removal of pharmaceuticals. In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals. However, these reactions occur generally at a slow rate, due to electron transfer limitations, and might be accelerated through redox mediators (RM). Carbon nanomaterials (CM) have been effective RM in the biological reduction of other pollutants. For instance, CNT@2%Fe were found to increase 76-fold the biological reduction of Acid Orange 10. The magnetic properties of those composites allow their easier recover after the process by using a magnetic field. In this study, CNT and CNT@2%Fe were studied in the anaerobic removal of Ciprofloxacin (CIP). Furthermore, the potential contribution of adsorption and biodegradation processes for CIP removal was assessed.
Toxicity assessment is highly important as it is desired that the products formed after the process are not more toxic than the initial compound. Moreover, the evaluation of the possible contribution of nanomaterials used in the process for the final toxic effect of threated solution, is crucial. In this sense, the detoxification of the treated solutions was evaluated towards Vibrio fischeri.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio
A wide perspective of carbon materials as catalysts for bioremediation of emerging pollutants and methanogenesis
Biotransformation of emerging pollutants under anoxic conditions can be accelerated by carbon materials
(CM) acting as redox mediators. CM have been also extensively reported as facilitating external electron transfer in
methanogenic processes. Here, different CM including magnetic carbon materials (C@MNP), were prepared,
characterized and applied as RM on the biological reduction of Acid Orange 10 (AO10) and ciprofloxacin (CIP). CIP
could be biologically removed in the presence of CNT and CNT@2%Fe, and AO10 decolourisation rates were 79-fold
higher in the assays with CNT@2%Fe. The effect of carbon nanotubes (CNT) on the activity of several pure cultures of
methanogens was also investigated, demonstrating that CNT could accelerate up to 17-fold the methane production rate.
It is evident from this work that carbon materials with different chemical and textural characteristics can accelerate
significantly bioremediation and methanogenic processes. The fact that concentrations as low as 0.1 g/L were used with
positive effects, is remarkable in terms of economic feasibility of using CM as efficient catalysts in both processes.info:eu-repo/semantics/publishedVersio
Galactodendritic Phthalocyanine Targets Carbohydrate- Binding Proteins Enhancing Photodynamic Therapy
Photosensitizers (PSs) are of crucial importance in the effectiveness of photodynamic therapy (PDT) for cancer. Due to their
high reactive oxygen species production and strong absorption in the wavelength range between 650 and 850 nm, where
tissue light penetration is rather high, phthalocyanines (Pcs) have been studied as PSs of excellence. In this work, we report
the evaluation of a phthalocyanine surrounded by a carbohydrate shell of sixteen galactose units distributed in a dendritic
manner (PcGal16) as a new and efficient third generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UMUC-
3. Here, we define the role of galacto-dendritic units in promoting the uptake of a Pc through interaction with GLUT1
and galectin-1. The photoactivation of PcGal16 induces cell death by generating oxidative stress. Although PDT with PcGal16
induces an increase on the activity of antioxidant enzymes immediately after PDT, bladder cancer cells are unable to recover
from the PDT-induced damage effects for at least 72 h after treatment. PcGal16 co-localization with galectin-1 and GLUT1
and/or generation of oxidative stress after PcGal16 photoactivation induces changes in the levels of these proteins.
Knockdown of galectin-1 and GLUT1, via small interfering RNA (siRNA), in bladder cancer cells decreases intracellular uptake
and phototoxicity of PcGal16. The results reported herein show PcGal16 as a promising therapeutic agent for the treatment
of bladder cancer, which is the fifth most common type of cancer with the highest rate of recurrence of any cancer
Detoxification of ciprofloxacin in an anaerobic bioprocess supplemented with magnetic carbon nanotubes: contribution of adsorption and biodegradation mechanisms
In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals in wastewaters. Common electron transfer limitations benefit from the acceleration of reactions through utilization of redox mediators (RM). This work explores the potential of carbon nanomaterials (CNM) as RM on the anaerobic removal of ciprofloxacin (CIP). Pristine and tailored carbon nanotubes (CNT) were first tested for chemical reduction of CIP, and pristine CNT was found as the best material, so it was further utilized in biological anaerobic assays with anaerobic granular sludge (GS). In addition, magnetic CNT were prepared and also tested in biological assays, as they are easier to be recovered and reused. In biological tests with CNM, approximately 99% CIP removal was achieved, and the reaction rates increased ?1.5-fold relatively to the control without CNM. In these experiments, CIP adsorption onto GS and CNM was above 90%. Despite, after applying three successive cycles of CIP addition, the catalytic properties of magnetic CNT were maintained while adsorption decreased to 29 ± 3.2%, as the result of CNM overload by CIP. The results suggest the combined occurrence of different mechanisms for CIP removal: adsorption on GS and/or CNM, and biological reduction or oxidation, which can be accelerated by the presence of CNM. After biological treatment with CNM, toxicity towards Vibrio fischeri was evaluated, resulting in ? 46% detoxification of CIP solution, showing the advantages of combining biological treatment with CNM for CIP removal.This study was supported by the Portuguese Foundation for Science and Technology
(FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation
(NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the
scope of Norte2020-Programa Operacional Regional do Norte. Ana Rita Silva holds an FCT grant
SFRH/BD/131905/2017. Cátia S.N. Braga holds an FCT grant SFRH/BD/132003/2017. This work was
also financially supported by: Base Funding-UIDB/50020/2020 of the Associate Laboratory LSRE LCM-funded by national funds through FCT/MCTES (PIDDAC). OSGPS acknowledges FCT fund ing under the Scientific Employment Stimulus-Institutional Call CEECINST/00049/2info:eu-repo/semantics/publishedVersio
Preserved monocyte-derived dendritic cell differentiation and maturation in the presence of HIV-2 envelope
© 2012 Mary Ann Liebert, Inc. publishers. All rights reserved, USA and worldwide.Dendritic cells (DCs) are fundamental for the initiation of immune responses and are important players in AIDS immunopathogenesis. Impairment of DC function may result from bystander effects of HIV-1 envelope proteins independently of direct HIV-1 infection. HIV-2 envelope proteins are thought to interact with a broader range of receptors than those of HIV-1, and have been shown to have T cell immunosuppressive properties mediated by monocytes. The effects of HIV-2 envelope on DC differentiation and maturation were investigated. The modulatory properties of the HIV-2 envelope on DC generated from monocytes were assessed using both recombinant proteins (HIV-2(ROD) and HIV-2(ALI)) and whole chemically inactivated virus (aldrithiol-2-treated HIV-2(ROD)). DC phenotype was assessed by flow cytometry and DC function by their ability to stimulate allogeneic T cells and to produce cytokines. We demonstrate that HIV-2 Env had no effects upon DC differentiation and maturation despite its broad receptor usage and ability to modulate monocyte function. It is plausible to speculate that a reduced ability of the HIV-2 Env to impair myeloid DC function could represent a contributory factor to the relatively benign course of HIV-2 disease.This work was supported by grants from “Fundação para a Ciência e a Tecnologia” (FCT) and by
“Programa Operacional Ciência e Inovação 2010” (POCI2010) to AES. RC and RBF
received scholarships from FCT co-financed by POCI 2010 and FSE, and AB from
GlaxoSmithKline
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