132 research outputs found
Maturity-Onset Diabetes of the Young: a Type of Diabetes Still Underdiagnosed in Clinical Practice
O termo MODY (Maturity Onset Diabetes of the Young) surgiu pela primeira vez nos anos 60, englobando um grupo de doenças monogénicas de transmissão autossómica dominante e apresentação clássica em adolescentes ou adultos jovens. A diabetes tipo MODY constitui cerca de 1-2% de todos os diagnósticos de diabetes na Europa. Atualmente encontram-se caracterizados 14 genes responsáveis por esta patologia, os quais resultam em apresentações clínicas muito heterogéneas, sendo as mais comuns mutações nos genes da glucocinase (MODY 2) e Hepatocyte Nuclear Factor 1α/4α (MODY 3 e MODY 1). Os doentes podem apresentar ou não sintomatologia clássica da diabetes e um dos grandes desafios é o diagnóstico diferencial com a diabetes tipo 1 e tipo 2, pelas características fenotípicas sobreponíveis. Neste sentido, o teste genético afigura-se como muito importante, na medida em que fornece não só uma vantagem terapêutica (doentes com MODY 1 e MODY 3 erradamente diagnosticados como diabetes tipo 1 poderão abandonar a terapêutica com insulina de forma segura, uma vez que apresentam elevada sensibilidade ao tratamento com sulfonilureias), como também uma determinação do prognóstico e necessidade de vigilância de complicações microvasculares e extra-pancreáticas (o MODY 5 tem elevada incidência de patologia renal não-diabética), passando pela orientação de familiares e decisão acerca de instituição de terapêutica durante a gravidez. Esta revisão pretende reunir e resumir a informação existente acerca dos subtipos de MODY já conhecidos, diagnóstico diferencial, complicações e terapêutica, bem como a importância do teste genético e implicações desta patologia no feto.info:eu-repo/semantics/publishedVersio
The sol-gel entrapment of noble metals in hybrid silicas: a molecular insight
BACKGROUND: Why are metal nanoparticles sol-gel entrapped in ORMOSIL so active and stable? In other words, why ORMOSIL-entrapped metal nanoparticles are more active and selective than many heterogenized counterparts, including silica-entrapped noble metals? RESULTS: Unveiling specific interactions between MNPs and the molecular structure of ORMOSIL, this work investigates subtle structural aspects through DRIFT spectroscopy. CONCLUSIONS: The results point to interactions between entrapped Pd and Pt nanocrystallites with the organosilica sol-gel cages similar to those taking place in enzymes
Economic and technical feasibility of betanin and pectin extraction from opuntia ficus-indica peel via microwave-assisted hydrodiffusion
Investigating the feasibility of betanin and pectin extraction from Opuntia ficus-indica peel via microwave-assisted hydrodiffusion and gravity, this study identifies selected important economic and technical aspects associated with this innovative production route starting from prickly pear fruit discards. Which benefits would be derived from this process? Would production be limited to Opuntia-growing countries or, likewise to what happens with dried lemon peel chiefly imported from Argentina, would production take place abroad also? Can distributed manufacturing based on clean extraction technology compete with centralized production using conventional chemical processes
Microplastics effects in Scrobicularia plana
One of the most common plastics in the marine environment is polystyrene (PS) that can be broken down to micro sized particles. Marine organisms are vulnerable to the exposure to microplastics. This study assesses the effects of PS microplastics in tissues of the clam Scrobicularia plana. Clams were exposed to 1mgL-1(20μm) for 14days, followed by 7days of depuration. A qualitative analysis by infrared spectroscopy in diffuse reflectance mode period detected the presence of microplastics in clam tissues upon exposure, which were not eliminated after depuration. The effects of microplastics were assessed by a battery of biomarkers and results revealed that microplastics induce effects on antioxidant capacity, DNA damage, neurotoxicity and oxidative damage. S. plana is a significant target to assess the environmental risk of PS microplastics.info:eu-repo/semantics/publishedVersio
Covalent and noncovalent hybrids of di-amino porphyrin functionalized graphene oxide and their interaction with gold nanoparticles
Porphyrin functionalization of graphene oxide (GO) influenced the plasmonic effect of gold nanoparticles (AuNP). The former was achieved by modification of GO with 5,10-bis(4-aminophenyl)-15,20-diphenylpor-phyrin, P(NH2)2,adj, by noncovalent interactions as well as by covalent association, following standard chemis-try. The success of the chemical functionalization of GO with P(NH2)2,adj, was confirmed by FTIR. Steady-state and time-resolved fluorescence showed a strong fluorescence quenching of porphyrin in the presence of GO, indicative of a photoinduced electron transfer process from porphyrin units to GO, which acts as an electron acceptor. The surface plasmon coupling effect promoted by the AuNP@GO hybrids, proved to be effective only in the case of the noncovalent hybrid, detected through the decrease of the porphyrin fluorescence lifetime and increase in the emission intensity in solution, in good agreement with FLIM results on deposited samples.info:eu-repo/semantics/publishedVersio
Liquid mixtures involving hydrogenated and fluorinated alcohols: thermodynamics, spectroscopy, and simulation
This article reports a combined thermodynamic, spectroscopic, and Computational study on the interactions and structure of binary mixtures of hydrogenated and fluorinated substances that simultaneously interact through strong hydrogen bonding. Four binary mixtures of hydrogenated and fluorinated alcohols have been studied, namely, (ethanol + 2,2,2-trifluoroethanol (TFE)), (ethanol + 2,2,3,3,4,4,4-heptafluoro-1-butanol), (1-butanol (BuOH) + TFE), and (BuOH + 2,23,4,4,4-heptafluoto-1-butanol). Excess molar volumes and vibrational spectra of all four binary mixtures have been measured as a function of composition at 298 K, and molecular dynamics simulations have been performed. The systems display a complex behavior when compared with mixtures of hydrogenated alcohols and mixtures of alkanes and perfluoroalkanes. The combined analysis of the results from different approaches indicates that this results from a balance between preferential hydrogen bonding between the hydrogenated and fluorinated alcohols and the unfavorable dispersion forces between the hydrogenated and fluorinated chains. As the chain length increases, the contribution of dispersion increases and overcomes the contribution of H-bonds. In terms of the liquid structure, the simulations suggest the possibility of segregation between the hydrogenated and fluorinated segments, a hypothesis corroborated by the spectroscopic results. Furthermore, a quantitative analysis of the infrared spectra reveals that the presence of fluorinated groups induces conformational changes in the hydrogenated chains from the usually preferred all-trans to more globular arrangements involving gauche conformations. Conformational rearrangements at the CCOH dihedral angle upon mixing are also disclosed by the spectra
Analysis and diagnosis of timber structures in Porto historical centre
The historical centre of Porto was considered in 1996 UNESCO World Heritage to the outstanding universal value of the site, with urban fabric and historic buildings that bear remarkable testimony to the development over the past thousand years of an important European city". In order to contribute to the maintenance of this remarkable set of buildings, with historical, architectural, constructive and heritage value, in opposition to the continuous build heritage degradation process and the population dislocation from the centre to the surroundings, NCREP-FEUP have been participating in many rehabilitation projects, analyzing the conservation state of building structural elements (stone masonry walls and timber floors and roofs). The focus of the present paper is given to the evaluation of the physical state of timber structural elements, namely to the various instruments used on the Analysis and Diagnosis phases, in particular to the non destructive (NDT), medium-destructive (MDT) and, in a certain context, destructive testing techniques
Water enema computed tomography (WE-CT) in the local staging of low colorectal neoplasms: comparison with transrectal ultrasound
New neuroprotective effect of lemon integropectin on neuronal cellular model
Lemon IntegroPectin obtained via hydrodynamic cavitation of organic lemon processing waste in water shows significant neuroprotective activity in vitro, as first reported in this study in-vestigating the effects of both lemon IntegroPectin and commercial citrus pectin on cell viability, cell morphology, reactive oxygen species (ROS) production, and mitochondria perturbation induced by treatment of neuronal SH-SY5Y human cells with H2O2. Mediated by ROS, including H2O2 and its derivatives, oxidative stress alters numerous cellular processes, such as mitochondrial regulation and cell signaling, propagating cellular injury that leads to incurable neurodegenerative diseases. These results, and the absence of toxicity of this new pectic substance rich in adsorbed flavonoids and terpenes, suggest further studies to investigate its activity in preventing, retarding, or even curing neurological diseases
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