Glioblastoma (GBM) is the most common and lethal tumor of the central nervous system. The natural history of treated GBM remains very poor with 5-year survival rates of 5 %. Survival has not ...significantly improved over the last decades. Currently, the best that can be offered is a modest 14-month overall median survival in patients undergoing maximum safe resection plus adjuvant chemoradiotherapy. Prognostic factors involved in survival include age, performance status, grade, specific markers (MGMT methylation, mutation of IDH1, IDH2 or TERT, 1p19q codeletion, overexpression of EGFR, etc.) and, likely, the extent of resection. Certain adjuncts to surgery, especially cortical mapping and 5-ALA fluorescence, favor higher rates of gross total resection with apparent positive impact on survival. Recurrent tumors can be offered re-intervention, participation in clinical trials, anti-angiogenic agent or local electric field therapy, without an evident impact on survival. Molecular-targeted therapies, immunotherapy and gene therapy are promising tools currently under research.
The management of diffuse supratentorial WHO grade II glioma remains a challenge because of the infiltrative nature of the tumor, which precludes curative therapy after total or even supratotal ...resection. When possible, functional-guided resection is the preferred initial treatment. Total and subtotal resections correlate with increased overall survival.
High
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patients (age >40, partial resection), especially IDH-mutated and 1p19q-codeleted oligodendroglial lesions, benefit from surgery plus adjuvant chemoradiation. Under the new 2016 WHO brain tumor classification, which now incorporates molecular parameters, all diffusely infiltrating gliomas are grouped together since they share specific genetic mutations and prognostic factors. Although low-grade gliomas cannot be regarded as
benign
tumors, large observational studies have shown that median survival can actually be doubled if an early, aggressive, multi-stage and personalized therapy is applied, as compared to prior
wait
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and
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see
policy series. Patients need an honest long-term therapeutic strategy that should ideally anticipate neurological, cognitive and histopathologic worsening.
The aim of this work was to evaluate the corrosion behavior of the AA6061 and AlSi10Mg alloys produced by extruded and additive manufacturing (selective laser melting, SLM). Alloys were immersed in ...two electrolytes in H2O and 3.5 wt. % NaCl solutions at room temperature and their corrosion behavior was studied by electrochemical noise technique (EN). Three different methods filtered EN signals, and the statistical analysis was employed to obtain Rn, the localization index (LI), Kurtosis, skew, and the potential spectral density analysis (PSD). The Energy Dispersion Plots (EDP) of wavelets method was employed to determine the type of corrosion and the Hilbert–Huang Transform (HHT), analyzing the Hilbert Spectra. The result indicated that the amplitude of the transients in the time series in potential and current is greater in the AlSi10Mg alloy manufactured by additive manufacturing. The amplitude of the transients decreases in both alloys (AA6061 and AlSi10Mg) as time increases.
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•Supported NiO can substantially improve the catalytic performance of bulk NiO in the ODH of ethane.•The increase in the catalytic activity is directly related to a decrease in NiO ...particle size.•High selectivity to ethylene is related with a higher number of nickel and oxygen vacancies.
We report on the effect of NiO-support interactions on the chemical nature of Ni species in a series of supported NiO catalysts for the ODH of ethane. SiO2, TiO2-anatase, a high surface area TiO2 and a porous clay heterostructure (PCH) with TiO2 and SiO2 pillars were used as supports, which led to a selectivity to ethylene in the range 30–90% over supported NiO catalysts. The catalysts were characterized by means of XRD, N2-Adsorption, H2-TPR, XPS and in situ (under H2 reductive atmosphere) and ex situ XAS spectroscopy. The catalytic performance of supported materials is discussed in terms of their reducibility and specific reduction kinetics, but also taking into account the specific chemical nature of Ni species on each catalyst. The influence of the particle size and the presence of Ni and O vacancies on the catalytic performance in the ODH of ethane is inferred.
NiO and metal-promoted NiO catalysts (M-NiO, with a M/(M+Ni) atomic ratio of 0.08, with M = Nb, Sn, or La) have been prepared, tested in the oxidative dehydrogenation (ODH) of ethane, and ...characterized by means of XRD, TPR, HRTEM, Raman, XPS, and in situ XAS (using H2/He, air or C2H6/He mixtures). The selectivity to ethylene during the ODH of ethane decreases according to the following trend: Nb–NiO ≈ Sn–NiO > La–NiO > NiO, whereas the catalyst reducibility (determined by both TPR and XAS using H2/He mixtures) shows the opposite trend. However, different reducibility and catalytic behavior in the absence of oxygen (ethane/He mixtures) have been observed, especially when comparing Nb- and Sn-promoted NiO samples. These differences can be ascribed mainly to a different phase distribution of the promoter. The results presented here are discussed in terms of the nature of active and selective sites for ODH of ethane in selective and unselective catalysts, but also the role of promoters and the importance of their phase distribution.
Solid acid catalysts based on WO3–SiO2 and WO3–ZrO2–SiO2 were prepared by one-pot non-hydrolytic sol–gel method and tested in the gas phase glycerol dehydration to acrolein. Their structural and ...textural characteristics were determined by X-ray diffraction (XRD), N2 adsorption, X-ray energy dispersive spectroscopy (XEDS), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Their acid characteristics were studied by both temperature programmed desorption of ammonia (NH3-TPD) and FTIR of adsorbed pyridine. Under our operating conditions, all the catalysts were active and selective in the transformation of glycerol to acrolein, which was always the main reaction product. The high selectivity to acrolein is achieved on catalysts presenting a higher proportion of Brønsted acid sites. In addition, the role of oxygen in the feed on catalytic performance of these catalysts is also discussed.
Antibiotics have been beneficial for human and animal health. However, an excessive use in livestock and a deficient management of the carcasses can lead to adverse effects in the scavengers that ...ingest them, especially in “supplementary feeding sites” (SFS). The aim of this study was to assess the potential risk of exposure to antibiotics for an endangered population of Cinereous vultures (Aegypius monachus) from southeastern Portugal. Hence, a multi-residue method based on QuEChERs was adapted and validated to analyse, in small volumes of tissues, the most frequent antibiotics used in livestock. The method was applied to 87 samples of liver, muscle and kidney from 7 goats and 25 sheep disposed in SFS. According to questionnaires to farmers, the animals had not been treated with antibiotics, but analyses showed residues in 29% of the samples. Antibiotics were more frequent in goats (42.9%) than in sheep (24.2%), and oxytetracycline and trimethoprim were the most common (both 13.8%). Oxytetracycline, the most common antibiotic for livestock in Portugal, showed the highest concentration (1452.68 ng g−1). To our knowledge, this is the first study of presence of antibiotics in carrion from SFS. The concentrations of antibiotics in carrion do not seem to pose a risk of acute intoxication for adult Cinereous vultures. However, subtle and likely chronic exposure with unknown health consequences may occur, which requires more research. Moreover, the results of this first study can be used in future studies to assess the risk for avian scavengers.
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•There is a need to assess the exposure to pharmaceuticals in Cinereous vultures.•A QuEChERS technique was validated to analyse antibiotics in animal tissues.•The carrion disposed to Cinereous vultures was analysed.•Oxytetracycline was the most common and abundant antibiotic in the carrion.•These results can be used to assess the risk to antibiotics in the vultures.
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