24 research outputs found

    Co-Mn oxides supported on hierarchical macro-mesoporous silica for CO and VOCs oxidation

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    The hierarchical macro-mesoporous silica (MMS) was used for a first time as a support for catalysts for oxidation reactions. The macro-mesoporous silica was synthesized by the emulsions templating mechanism and modified separately or simultaneously using cobalt and manganese oxides. The obtained materials were characterized by different physicochemical methods and tested in the oxidation of CO and n-hexane combustion reactions. The modification of the MMS materials does not change significantly the mesopores characteristics; however, its pores are partially blocked by the oxides. For Co-MM sample agglomerates consisting of Co3O4 with average size of 100−150 nm and small spherical aggregates, encapsulated in the mesopores are formed. The amorphous manganese oxide preferentially fills up the mesopores in Mn-MM sample. Mixed oxide Co-Mn phases situated in the mesoporous network are formed in the bi-component Co-Mn samples. No significant change is observed either in the texture, or in the structural features of the catalysts after reaction. The highest catalytic activity for Co-MM sample in CO and n-hexane oxidation is related to the predomination of Co3+ species on the surface of Co3O4 and the more accessible oxide particles located outside the mesopores. The encapsulation of mixed Co-Mn oxides particles in the pores of the macro-mesoporous silica is responsible for a lower catalytic activity in comparison with that of the mono-component cobalt sample

    International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009

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    The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved

    A phase 1 randomized study evaluating the effect of omeprazole on the pharmacokinetics of a novel 5-hydroxytryptamine receptor 4 agonist, revexepride (SSP-002358), in healthy adults

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    David Pierce,1 Mary Corcoran,2 Maria Velinova,3 Stuart Hossack,4 Mieke Hoppenbrouwers,5 Patrick Martin,21Shire, Basingstoke, UK; 2Shire, Wayne, PA, USA; 3PRA International, Zuidlaren, the Netherlands; 4Covance, Leeds, UK; 5Shire-Movetis NV, Turnhout, BelgiumBackground: About 30% of patients with gastroesophageal reflux disease continue to experience symptoms despite treatment with proton pump inhibitors. The 5-hydroxytryptamine 4 receptor agonist revexepride (SSP-002358) is a novel prokinetic that stimulates gastrointestinal motility, which has been suggested as a continued cause of symptoms in these patients. The aim of this study was to assess whether revexepride pharmacokinetics were affected by co-administration of omeprazole, in preparation for a proof-of-concept evaluation of revexepride added to proton pump inhibitor treatment.Methods: In this phase 1, open-label, randomized, two-period crossover study, healthy adults aged 18–55 years were given a single dose of revexepride 1 mg or revexepride 1 mg + omeprazole 40 mg. Pharmacokinetic parameters were assessed for up to 48 hours after administration of the investigational product. Adverse events, clinical chemistry and hematology parameters, electrocardiograms, and vital signs were monitored.Results: In total, 42 participants were enrolled and 40 completed the study. The median age was 24 years (18–54 years), 55% were women and 93% were white. The pharmacokinetic parameters of revexepride were similar without or with omeprazole co-administration. The mean area under the plasma concentration–time curve from time 0 to infinity (AUC0–∞) was 23.3 ng · h/mL (standard deviation [SD]: 6.33 ng · h/mL) versus 24.6 ng · h/mL (SD: 6.31 ng · h/mL), and maximum plasma concentrations (Cmax) were 3.89 ng/mL (SD: 1.30 ng/mL) and 4.12 ng/mL (SD: 1.29 ng/mL) in participants without and with omeprazole, respectively. For AUC0–∞ and Cmax, the 90% confidence intervals for the ratios of geometric least-squares means (with:without omeprazole) were fully contained within the pre-defined equivalence limits of 0.80–1.25. Mean apparent terminal phase half-life was 9.95 hours (SD: 2.06 hours) without omeprazole, and 11.0 hours (SD: 3.25 hours) with omeprazole.Conclusion: Co-administration of the 5-hydroxytryptamine receptor 4 agonist revexepride with omeprazole did not affect the pharmacokinetics of revexepride in healthy adults.Keywords: revexepride, omeprazole, pharmacokinetics, gastroesophageal reflux diseas

    Co3O4-MnOx oxides supported on SBA-15 for CO and VOCs oxidation

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    International audienceMono-and bi-component cobalt and manganese samples were prepared by ''twosolvent'' technique using SBA-15 as a support. The obtained materials were characterized by SAXS (Small angle X-Ray scattering), N2 adsorption-desorption, X-ray diffraction, TEM (Transmission Electron Microscopy), X-ray photoelectron spectroscopy (XPS), TPR (Temperature-programmed reduction) and O2-TPD (Oxygen Temperature-programmed desorption). The catalytic properties were tested in the complete oxidation of propane, nhexane, and carbon monoxide. The modification of the SBA-15 materials with Co, Mn or simultaneously with both cobalt and manganese does not change significantly the mesoporous structure, however its pores are partially blocked by the oxides, resulting in the decrease in the specific surface area and in the pore volume. In the case of mono component Co-SBA-15, the clusters of Co3O4 are on the surface and they are partially located inside the pore system of SBA-15 while for Mn-SBA-15 sample, the oxide phases preferentially fill up the channels of SBA-15 forming nanowires. The mixed oxide nanowires are formed in the channels of CoMn-SBA-15 material along with small nanoparticles, aggregated outside of the channels. The mesoporous structure and morphology of SBA-15, type of oxide phases and the size of the oxide particles remain almost unchanged after tests in reaction of complete nhexane oxidation and this is valid for all studied samples. The observed resistance towards agglomeration can be attributed to the mesoporous structure. On the other hand, after reaction the surface concentration of different cobalt and manganese species undergoes significant changes, except for the sample with equimolar Co:Mn ratio. The most active catalyst among bi-component Co-Mn samples in all studied reactions, is the catalyst where the Co:Mn molar ratio is 1:0.5, which can be explained by the formation of finely divided oxides, thus ensuring highest reducibility and oxygen mobility
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