Two-dimensional low resolution raman spectroscopy applied to fast discrimination of clinically relevant microorganisms: a whole-organism fingerprinting approach

The discrimination of the bacteria that cause gastroenteritis through classical microbiological methods is very efficient in the great majority of the cases. However, the high cost of chemicals and the time spent for such identifications, about four days, could generate serious consequences for the patients. Thus, the search for low cost spectroscopic methods which would allow a fast and reagentless discrimination of these microorganisms is extremely relevant. In this work the main microorganisms that cause gastroenteritis: E. coli, S. chroleraesuis, S. flexneri were studied. For each of the microorganisms sixty different dispersions were prepared using physiological solution as solvent and its Raman spectra recorded. The 1D spectra obtained were similar, making it very difficult to differentiate the microorganisms. However, applying the 2D correlation method, it was possible to identify the microorganisms evaluated using the synchronous spectrum as whole-organism fingerprinting in a reduced time interval (~10 h).A diferenciação de bactérias causadoras de gastrenterites através de métodos microbiológicos clássicos é muito eficiente, na maior parte dos casos. Todavia, o elevado custo dos reagentes e o tempo necessário para tais determinações, cerca de 4 dias, podem causar sérias conseqüências, quando os pacientes são crianças, idosos ou adultos com baixa resistência imunológica. Assim, a pesquisa por métodos espectroscópicos de baixo custo, que permitam tais determinações com pouco uso de reagentes e em curtos intervalos de tempo é extremamente relevante. Neste trabalho os principais microrganismos causadores de gastrenterites, E. coli, S. chroleraesuis, S. flexneri foram avaliados. Foram preparadas sessenta dispersões para cada um dos microrganismos, usando solução fisiológica como solvente, e seus espectros adquiridos. Os espectros obtidos foram muito similares, tornando muito difícil a diferenciação dos microrganismos. Entretanto, aplicando a teoria de correlação generalizada em 2D, foi possível diferenciar os microrganismos avaliados usando o espectro síncrono como impressão digital do organismo em um curto intervalo de tempo (~10h).7378Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Aminoiron(III)–porphyrin–alumina catalyst obtained by non-hydrolytic sol-gel process for heterogeneous oxidation of hydrocarbons

An aminoiron(III) porphyrin immobilized on an alumina matrix was prepared and used as catalyst for the oxidation of organic substrates. Powder alumina had been prepared by a non-hydrolytic sol-gel method through condensation of aluminum chloride with anhydrous ethanol. Then, iron(III) [5,10,15,20-tetrakis(2,6-dichloro-3-aminophenyl)-porphyrin] was immobilized on the alumina powder under magnetic stirring, reflux, and inert atmosphere. Ultraviolet–visible and infrared spectroscopies, powder X-ray diffraction, scanning electron microscopy and thermal analysis were applied for characterizing the resulting material, confirming that the ironporphyrin was immobilized on the alumina support. The catalytic activity of ironporphyrin/alumina was evaluated in the oxidation of (Z)-cyclooctene and cyclohexane and in the Baeyer-Villiger oxidation of cyclohexanone using iodosylbenzene or hydrogen peroxide as oxygen donors. The novel immobilized catalyst proved to be a promising system for the efficient and selective oxidation of the organic substrates with 85–92% selectivity to the epoxide in the oxidation of alkenes and 25–41% to the ketone in the oxidation of cyclohexane. As for the Baeyer-Villiger oxidation of cyclohexanone, good conversion to ԑ-caprolactone was observed as well. The material is a reusable heterogeneous catalyst, which makes it more economically feasible than its homogeneous counterpar

Synthesis of indium tin oxide nanoparticles by a nonhydrolytic sol-gel method

Indium tin oxide nanoparticles were synthesized in two different sizes by a nonhydrolytic sol-gel method. These powders were then transformed into ITO via an intermediate metastable state at between 300 and 600 ºC. The presence of characteristic O-In-O and O-Sn-O bands at 480 and 670 cm-1 confirmed the formation of ITO. The X-ray diffraction patterns indicated the preferential formation of metastable hexagonal phase ITO (corundum type) as opposed to cubic phase ITO when the reflux time was less than 3 h and the heat treatment temperature was below 600 ºC. Particle morphology and crystal size were examined by scanning electron microscopy

Fenilsilicato dopado com Eu III obtido pelo método sol-gel

In this work, we report the synthesis and the photoluminescence features of a Eu(III)-doped modified silica matrix obtained by the sol-gel method. The matrix was prepared by reaction between tetraethylorthosilicate and phenyltriethoxysilane alkoxide. The hydrolysis occurred using basic catalysis. The solids were treated at 100, 200 and 300 ºC during 4 h and the structure was determined by thermogravimetric analysis (TG/DTG), nuclear magnetic resonance (NMR 29Si and 13C), infrared spectroscopy (IR) and photoluminescence (PL). The PL spectra display the Eu(III) lines characteristic of the ion, 5D0 -> 7F J (J=0, 1, 2, 3, 4), the blue emission as ascribed in the silica matrix. The NMR and TG showed the stability of hybrid silica

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group