70 research outputs found

    Metal-Substituted Microporous Aluminophosphates

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    This chapter aims to present the zeotypes aluminophosphates (AlPOs) as a complementary alternative to zeolites in the isomorphic incorporation of metal ions within all-inorganic microporous frameworks as well as to discuss didactically the catalytic consequences derived from the distinctive features of both frameworks. It does not intend to be a compilation of either all or the most significant publications involving metal-substituted microporous aluminophosphates. Families of AlPOs and zeolites, which include metal ion-substituted variants, are the dominant microporous materials. Both these systems are widely used as catalysts, in particular through aliovalent metal ions substitution. Here, some general description of the synthesis procedures and characterization techniques of the MeAPOs (metal-contained aluminophosphates) is given along with catalytic properties. Next, some illustrative examples of the catalytic possibilities of MeAPOs as catalysts in the transformation of the organic molecules are given. The oxidation of the hardly activated hydrocarbons has probably been the most successful use of AlPOs doped with the divalent transition metal ions Co2+, Mn2+, and Fe2+, whose incorporation in zeolites is disfavoured. The catalytic role of these MeAPOs is rationalized based on the knowledge acquired from a combination of the most advanced characterization techniques. Finally, the importance of the high specificity of the structure-directing agents employed in the preparation of MeAPOs is discussed taking N,N-methyldicyclohexylamine in the synthesis of AFI-structured materials as a driving force. It is shown how such a high specificity could be predicted and how it can open great possibilities in the control of parameters as critical in catalysis as crystal size, inter-and intracrystalline mesoporosity, acidity, redox properties, incorporation of a great variety of heteroatom ions or final environment of the metal site (surrounding it by either P or Al)

    Spectroscopic and computational insights on catalytic synergy in bimetallic aluminophosphate catalysts

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    A combined electronic structure computational and X-ray absorption spectroscopy study was used to investigate the nature of the active sites responsible for catalytic synergy in Co-Ti bimetallic nanoporous frameworks. Probing the nature of the molecular species at the atomic level has led to the identification of a unique Co-O-Ti bond, which serves as the loci for the superior performance of the bimetallic catalyst, when compared with its analogous monometallic counterpart. The structural and spectroscopic features associated with this active site have been characterized and contrasted, with a view to affording structure property relationships, in the wider context of designing sustainable catalytic oxidations with porous solids

    Incidence of and factors associated with SARS-CoV-2 infection among people living with HIV in Southern Spain after one year of pandemic

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    Whether people living with HIV (PLWH) are at greater risk of acquiring SARS-CoV-2 infection is currently unknown. Prospective serologic studies may allow seroincidence analyses, where all infections are accurately identified. Because of this, we evaluated the incidence of associated factors with and the clinical outcome of SARS-CoV-2 infection in PLWH in Southern Spain. This prospective cohort study included PLWH from a Tertiary University Hospital in Southern Spain. Patients were enrolled in the study if (1) they had attended as outpatients our Unit from 1 August 2019 to 8 February 2020 and (2) had two subsequent evaluations from 9 February 2020 to 4 March 2021. SARS-CoV-2 infections were diagnosed by PCR, antigen detection or serology. Seven hundred and nine PLWH were included in the study. Of them, 55 [7.8%, 95% confidence interval (95% CI) 5.9%-9.9%] patients developed SARS-CoV-2 infection. Between 18 May and 29 November 2020, the rate of seroconversion was 5.3% (95% CI: 3.1%-9.0%) for the general population in the area of Seville and 2.3% (95% CI: 1.3%-2.6%) for PLWH in this study (p = .001). After multivariable analysis, adjusted by age, sex, and risk factors for HIV infection, active tobacco use and CDC stage, active tobacco smoking was the only factor independently associated with lower risk of SARS-Cov-2 infection [Incidence rate ratio: 0.29 (95% CI 0.16-0.55) p < .001]. In conclusion, the incidence of SARS-CoV-2 infection among PLWH in Southern Spain during the ongoing pandemic was lower than that reported for the general population in the same area.This work was supported in part by the Instituto de Salud CarlosIII (Project ‘PI16/01443’), integrated in the national I+D+i 2013–2016andco-fundedbytheEuropeanUnion(ERDF/ESF,‘Investinginyour future’), by the Spanish Network for AIDS investigation (RIS)(www.red.es/redes/inicio)(RD16/0025/0010,RD16/0025/0040),asapartoftheNacionalI+D+I,ISCIIISubdirecciónGeneraldeEvaluaciónand the European Fund for Development of Regions (FEDER). JuanA.PinedareceivedaresearchextensiongrantfromtheProgramadeIntensificacióndelaActividaddeInvestigacióndelServicioNacionaldeSaludCarlosIII(I3SNS).FedericoGarciareceivedaresearchextensiongrantfromtheProgramadeIntensificacióndelaActividaddeInves-tigacióndelServicioAndaluzdeSalud.AnaïsCorma-GomezreceivedaRíoHortegagrantfromtheInstitutodeSaludCarlosIII(grantnum-ber CM19/00251). Funding for open access charge: Universidad deMálaga/CBU

    Prognostic value of non-invasive scores based on liver stiffness measurement, spleen diameter and platelets in HIV-infected patients

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    BACKGROUND AND AIMS: People living with HIV (PLWH) are at high risk for advanced chronic liver disease and related adverse outcomes. We aimed to validate the prognostic value of non-invasive scores based on liver stiffness measurement (LSM) and on markers of portal hypertension (PH), namely platelets and spleen diameter, in PLWH. METHODS: We combined data from eight international cohorts of PLWH with available non-invasive scores, including LSM and the composite biomarkers liver stiffness-spleen size-to-platelet ratio score (LSPS), LSM-to-Platelet ratio (LPR) and PH risk score. Incidence and predictors of all-cause mortality, any liver-related event and classical hepatic decompensation were determined by survival analysis, controlling for competing risks for the latter two. Non-invasive scores were assessed and compared using area under the receiver operating curve (AUROC). RESULTS: We included 1695 PLWH (66.8% coinfected with hepatitis C virus). During a median follow-up of 4.7 (interquartile range 2.8-7.7) years, the incidence rates of any liver-related event, all-cause mortality and hepatic decompensation were 13.7 per 1000 persons-year (PY) (95% confidence interval [CI], 11.4-16.3), 13.8 per 1000 PY (95% CI, 11.6-16.4) and 9.9 per 1000 PY (95% CI, 8.1-12.2), respectively. The AUROC of LSM was similar to that of the composite biomarkers, ranging between 0.83 and 0.86 for any liver-related event, 0.79-0.85 for all-cause mortality and 0.87-0.88 for classical hepatic decompensation. All individual non-invasive scores remained independent predictors of clinical outcomes in multivariable analysis. CONCLUSIONS: Non-invasive scores based on LSM, spleen diameter and platelets predict clinical outcomes in PLWH. Composite biomarkers do not achieve higher prognostic performance compared to LSM alone

    Prognostic value of non-invasive scores based on liver stiffness measurement, spleen diameter and platelets in HIV-infected patients.

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    BACKGROUND AND AIMS People living with HIV (PLWH) are at high risk for advanced chronic liver disease and related adverse outcomes. We aimed to validate the prognostic value of non-invasive scores based on liver stiffness measurement (LSM) and on markers of portal hypertension (PH), namely platelets and spleen diameter, in PLWH. METHODS We combined data from eight international cohorts of PLWH with available non-invasive scores, including LSM and the composite biomarkers liver stiffness-spleen size-to-platelet ratio score (LSPS), LSM-to-Platelet ratio (LPR) and PH risk score. Incidence and predictors of all-cause mortality, any liver-related event and classical hepatic decompensation were determined by survival analysis, controlling for competing risks for the latter two. Non-invasive scores were assessed and compared using area under the receiver operating curve (AUROC). RESULTS We included 1695 PLWH (66.8% coinfected with hepatitis C virus). During a median follow-up of 4.7 (interquartile range 2.8-7.7) years, the incidence rates of any liver-related event, all-cause mortality and hepatic decompensation were 13.7 per 1000 persons-year (PY) (95% confidence interval [CI], 11.4-16.3), 13.8 per 1000 PY (95% CI, 11.6-16.4) and 9.9 per 1000 PY (95% CI, 8.1-12.2), respectively. The AUROC of LSM was similar to that of the composite biomarkers, ranging between 0.83 and 0.86 for any liver-related event, 0.79-0.85 for all-cause mortality and 0.87-0.88 for classical hepatic decompensation. All individual non-invasive scores remained independent predictors of clinical outcomes in multivariable analysis. CONCLUSIONS Non-invasive scores based on LSM, spleen diameter and platelets predict clinical outcomes in PLWH. Composite biomarkers do not achieve higher prognostic performance compared to LSM alone

    Greener Method to Obtain a Key Intermediate of Vitamin E over Cu-ZSM-5

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    The catalytic oxidation of 2,3,5-trimethylphenol was performed over transition metals modified ZSM-5 zeolites employing hydrogen peroxide as oxidant under mild reaction conditions. Catalysts samples were characterized by several techniques (XRD, FTIR, BET, AA) and cristallinity and orthorhombic symmetry were confirmed for all of them. Best catalytic results were obtained for Cu-ZSM-5 sample, so further activity studies were done over this material. 2,3,5-trimethyl-1,4-benzoquinone was obtained as the main product of the selective oxidation. Reaction parameters (nature of the solvent, hydrogen peroxide concentration, reaction time, catalyst mass, substrate initial concentration and reaction temperature) were evaluated to reach the optimum reaction conditions. According to the obtained results, an apparent activation energy of 52.33 kJ/mol was calculated.Fil: Saux, Clara. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Centro de Investigacion y Tecnologia Quimica; Argentina. Universidad Tecnologica Nacional. Facultad Regional Cordoba; ArgentinaFil: Renzini, Maria Soledad. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Centro de Investigacion y Tecnologia Quimica; Argentina. Universidad Tecnologica Nacional. Facultad Regional Cordoba; ArgentinaFil: GĂłmez, Silvina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Centro de Investigacion y Tecnologia Quimica; Argentina. Universidad Tecnologica Nacional. Facultad Regional Cordoba; ArgentinaFil: Pierella, Liliana Beatriz. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Centro de Investigacion y Tecnologia Quimica; Argentina. Universidad Tecnologica Nacional. Facultad Regional Cordoba; Argentin

    Deep Eutectic Solvents (DESs) and their applications [forthcoming]

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    Deep Eutectic Solvents (DESs) and Their Application

    New insights into the genetic etiology of Alzheimer's disease and related dementias.

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    Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele

    New insights into the genetic etiology of Alzheimer's disease and related dementias

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    Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele
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