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Increasing global warming due to NOx, CO2, and CH4, is significantly harming ecosystems and life worldwide. One promising methodology is converting pollutants into valuable chemicals via photocatalytic processes (by reusable photocatalysts). In this context, the present work aimed to produce a Nb2O5 photocatalyst nanofiber system by electrospinning to convert CO2. Based on the collected data, the calcination at 600 ∘C for 2 h resulted in the best condition to obtain nanofibers with homogeneous surfaces and an average diameter of 84 nm. As a result, the Nb2O5 nanofibers converted CO2 mostly into CO and CH4, reaching values around 8.5 µmol g-1 and 0.55 µmol g-1, respectively.

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Photocatalysis is a promising alternative for the decontamination of effluents. In this paper, immobilized ZnO-based photocatalysts were obtained by pressing and by slip casting. The cylindrical pieces were heat-treated at 800°C. The samples were characterized by the method based on the principle of Archimedes, XRD, FTIR, Raman, diffuse reflectance and SEM. The samples obtained by slip casting presented lower apparent density (3.12 ± 0.04 g/cm3), higher apparent porosity (44.87 ± 0.47%) and smaller grain size (0.48 ± 0.05 µm) when compared to the pressed samples, with mean apparent density of 5.37 ± 0.08 g/cm3, apparent porosity of 1.56 ± 0.10% and grain size of 0.64 ± 0.02 µm. The performances of the samples were attested by the photocatalytic degradation of Rhodamine B (RhB) under UV-C irradiation (maximum intensity at 254 nm). The samples obtained by slip casting showed photocatalytic degradation between 80% and 90%, while the pressed samples showed degradation between 40% and 60%. The reuse of the photocatalysts was evaluated over five cycles of photocatalytic degradation, in which there was no loss of performance of the samples obtained by slip casting; however, the pressed samples showed a loss of photocatalytic efficiency starting from the third-cycle. Photocatalytic assays were carried out with different dye concentrations, in which the slip casting samples showed better photocatalytic efficiency (degradation of 80% for a RhB concentration of 10 mg/L) due to higher porosity and surface area compared to pressed samples, and there was a loss of performance in higher concentrations.

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Entamoeba histolytica is a pathogen that during its infective process confronts the host defenses, which damages the amoebic plasma membrane (PM), resulting in the loss of viability. However, it is unknown whether amoebic trophozoites are able to repair their PM when it is damaged. Acid sphingomyelinases (aSMases) have been reported in mammalian cells to promote endocytosis and removal of PM lesions. In this work, six predicted amoebic genes encoding for aSMases were found to be transcribed in the HM1:IMSS strain, finding that the EhaSM6 gene is the most transcribed in basal growth conditions and rendered a functional protein. The secreted aSMase activity detected was stimulated by Mg+2 and inhibited by Co+2. Trophozoites that overexpress the EhaSM6 gene (HM1-SM6HA) exhibit an increase of 2-fold in the secreted aSMase activity. This transfectant trophozoites exposed to pore-forming molecules (SLO, Magainin, ß-Defensin 2 and human complement) exhibited an increase from 6 to 25-fold in the secreted aSMase activity which correlated with higher amoebic viability in a Ca+2 dependent process. However, other agents that affect the PM such as hydrogen peroxide also induced an increase of secreted aSMase, but to a lesser extent. The aSMase6 enzyme is N- and C-terminal processed. Confocal and transmission electron microscopy showed that trophozoites treated with SLO presented a migration of lysosomes containing the aSMase towards the PM, inducing the formation of membrane patches and endosomes in the control strain. These cellular structures were increased in the overexpressing strain, indicating the involvement of the aSMase6 in the PM injury repair. The pore-forming molecules induced an increase in the expression of EhaSM1, 2, 5 and 6 genes, meanwhile, hydrogen peroxide induced an increase in all of them. In all the conditions evaluated, the EhaSM6 gene exhibited the highest levels of induction. Overall, these novel findings show that the aSMase6 enzyme from E. histolytica promotes the repair of the PM damaged with pore-forming molecules to prevent losing cell integrity. This novel system could act when encountered with the lytic defense systems of the host.

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Objetivo: Describir y caracterizar el perfil epidemiológico de las llamadas recibidas en el año 2010 correspondiente a exposiciones, por el Centro de Información Toxicológica de la Pontificia Universidad Católica de Chile. Método: Se realizó un estudio retrospectivo y descriptivo de las llamadas registradas por el CITUC durante el año 2010. Se analizaron los siguientes datos: número total de llamadas, lugar de la llamada, circunstancia de la exposición, tipo y número de los agentes involucrados, vías de exposición, tiempo desde la exposición, género y edad de los pacientes. Resultados: Se registraron 29.592 llamadas. 45,2 por ciento de las consultas provenían del hogar y 53,2 por ciento de instalaciones médicas. 69,3 por ciento fueron exposiciones accidentales y 27,6 por ciento intencionales. Los medicamentos se presentaron como agente causal de una exposición en 58,4 por ciento de las llamadas, seguidos por los productos de uso doméstico (18,7 por ciento) y plaguicidas (5,8 por ciento). La ingestión fue la vía de exposición que predominó en un 79,3 por ciento del total de casos. 41,0 por ciento del total de las llamadas, se realizaron dentro de la primera hora post-exposición. Las exposiciones en niños menores de 14 años correspondieron a 51,6 por ciento de las llamadas. Conclusiones: Los medicamentos constituyen el principal agente involucrado en intoxicaciones. La principal vía de exposición es la ingesta y el principal grupo de población afectado son los niños menores de 14 años,. Estos indicadores muestran la necesidad imperante de desarrollar campañas de prevención e información avaladas por el Ministerio de Salud, respecto al correcto uso de los medicamentos, como también la introducción del envase resistente ala manipulación de los niños y la educación de la población.

Objective: To describe and to characterize the epidemiologoc profile of the entering pone calls in 2010 belonging to exposures by the Centro de Información Toxicológica de la Pontificia Universidad Católica de Chile. Method: A retrospective and descriptive study of pone calls registered by the CITUC has been made during 2010. The following has been analyzed: total pone calls number, place of the call, exposure circumstances, kind and number ofagents involved, exposure way, time from exposure, gender and age of the patients. Outcomes: 29.592 phone calls were registered. 45,2 percent of the questions came from home and 53,2 percent from medical institutions. 69,3 percent were non intented exposures and 27,6 percent were intented. The drugs were the causal agent of exposures in 58,4 percent of the phone calls, followed by cleaning use products (18,7 percent) and insecticides (5,8 percent). Swallowing was the predominant exposure way with 79,3 percent of the total. 41 percent of total of phone calls, were made in the first hour after exposure. The children under 14 years exposure cases, were were 51,6 percent of total phone calls. Conclusions: Medical drugs are the principal involved agent in intoxications. The main way of exposition is swallowing and the major population group involved is children under 14 years. These indicators shows the need of developing prevention and information campaigns supported by Secretary of Health, oriented to right use of drugs, as well as the use of safety drug boxes for children and population education.

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Neodymium calcium titanate, (Ca(0.99)Nd(0.01))TiO(3) powders were synthesized by the complex polymerization method and heat treated at different temperatures for 2 h under air atmosphere. The structural evolution of these powders as a function of heat treatment temperature was analyzed by X-ray diffraction (XRD) and micro-Raman (MR) spectroscopy. The optical properties were investigated by Ultraviolet-visible (UV-vis) absorption spectroscopy and Photoluminescence (PL) measurements. XRD patterns, Rietveld refinement and MR spectra indicated that the powders heated treated at 750 degrees C for 2 h present an orthorhombic structure without secondary phases. UV-vis measurements suggested the presence of intermediary energy in disordered (Ca(0.99)Nd(0.01))TiO(3) powders. Broad and narrow bands were observed in the PL spectra of these powders when excited with 350 nm wavelength. The broad bands were associated to the structural defects and/or p-d electronic transitions while, the narrow bands were ascribed to f-f transitions arising from Nd(3+) ions.

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A simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of memantine (I) in human plasma is presented. Sample preparation consisted of the addition of amantadine (II) as internal standard (IS), liquid-liquid extraction in basic conditions using a mixture of diethyl ether-chloroform (7:3, v/v) as extracting solvent, followed by centrifugation, solvent evaporation and sample reconstitution in methanol. Both I and II (internal standard) were analyzed using a C18 column and a mobile phase composed of methanol-water-formic acid (80:20:0.1, v/v/v). Eluted compounds were monitored using positive mode electrospray (ES) tandem mass spectrometry. The analyses were carried out by selected reaction monitoring (SRM) using the parent to daughter combinations of m/z 180>163 (memantine) and m/z 152>135 (amantadine). The peak areas from the analyte and IS were used for quantification of I. The achieved limit of quantification (LOQ) was 0.1 ng/mL; the assay exhibited a linear dynamic range of 0.1-50.0 ng/mL with a determination coefficient (r2) of at least 0.98. Validation results on linearity, specificity, accuracy, precision and stability, as well as on application to the analysis of samples taken up to 320 h after oral administration of 20mg (two 10mg capsules) of I in healthy volunteers demonstrated the applicability to bioequivalence studies.

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BACKGROUND & AIMS: Inflammatory cytokine polymorphisms are associated with gastric adenocarcinoma in Helicobacter pylori-infected patients in Europe and Asia. We investigated the cytokine profile in the Latino population, specifically Honduras, a high-incidence region, and the use of the combination prevalence of H pylori and genotypes in identifying high-risk populations. METHODS: A population-based case-control study identified 170 incident gastric cancer cases and 162 healthy village controls. Interleukin (IL)-Ibeta-511, IL-1RN, IL-10-1082, and tumor necrosis factor-alpha-308 genotypes were determined. We define the combination prevalence index (CPI) as the product of H pylori and IL-1beta-511T+ genotype prevalence in healthy subjects. Medline identified gastric cancer studies to facilitate country-specific CPI calculations. RESULTS: In healthy, population-based Honduran controls, IL-1beta-511T+ prevalence was 81% (95% confidence interval, 75%-87%; CT, 57%; TT, 25%), which was among the highest reported. IL-10-1082A+ prevalence was 93% (95% confidence interval, 88%-97%), mirroring Asian populations. Seventeen percent were homozygous for both proinflammatory cytokines (TT/AA), with increased risk among cases (odds ratio, 2.6; 95% confidence intervals, 1.0-6.8). Tumor necrosis factor-alpha polymorphisms were nearly absent. Endemic H pylori infection (85%) was confirmed. Importantly, the CPI association with country incidence is highly significant (P = .0057), based on 16 global populations and Honduras. Sensitivity analysis confirms a robust CPI. CONCLUSIONS: The CPI, based on IL-1beta genotypes, has a strong association with country-specific gastric cancer incidence. The CPI correlation supports the chronic inflammation carcinogenesis model, and may explain the geographic variation. We report a novel cytokine profile in Honduras that mirrors Asian populations and explains the high incidence rates. This may have dyspepsia management and screening implications for the growing US Latino population.

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Calcium channel blockers are widely used in all-aged populations. The drugs are generally safe in therapeutic dosage, but severe side effects with elevated intake are increasingly described, mainly in adult patients. We report an adolescent girl who intentionally ingested an overdose of nifedipine.

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This study was conducted to evaluate usefulness of the physiologic stability index (PSI) in a pediatric intensive care Unit (PICU) of a University based hospital at Santiago, Chile. Subjects include all patients (n = 152) consecutively admitted to our PICU between april 1987 and august 1988. The PSI system was applied during the first four days from admission. The age of the patients ranged from 10 days to 15 years. Scores obtained from survivors and non survivors were compared using an analysis of variance. For maximum PSI, survivors had significantly lower scores (9.39 points) that non survivors (21.71 points). Multiple logistic regression was used to display associations between mean obtained scores and probability of death and a curve was plotted which is similar to that obtained in previous experiences from other countries.

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