13 research outputs found

    Aldol Condensation of Furfural with Acetone Over Mg/Al Mixed Oxides. Influence of Water and Synthesis Method

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    Aldol condensation of furfural and acetone (an important initial step to obtain diesel from biomass) was studied over MgAl mixed oxides. The influence of the utilization of microwaves and/or a surfactant (Pluronic 123) during the synthesis as well as the use of water (either pre-hydrating the solids before catalytic studies or in water/toluene mixtures as the reaction medium) is discussed. The combined use of Pluronic 123 and microwaves led to solids with bigger pore sizes, exhibiting lower basicity and higher acidity than the conventional synthetic method, thus resulting in an increase in the yield of the desired product of condensation, comprising two molecules of furfural and one of acetone (F2Ac). As for the influence of water, re-hydration of the mixed oxides was detrimental to activity, probably as a result of the partial blocking (solvation) of active sites. On the contrary, the increase in water percentage in the reaction medium resulted in higher conversions, though selectivity to F2Ac decreased. The weakening of the C=O bond of furfural in the presence of water as well as the higher solubility of the first condensation product (FAc) in toluene, as compared to water, could account for that. A 44.5% yield of F2Ac (66% conversion) after 16 h was obtained with the most active solid, which maintained the activity for three consecutive reactions

    Biochars from Olive Stones as Carbonaceous Support in Pt/TiO<sub>2</sub>-Carbon Photocatalysts and Application in Hydrogen Production from Aqueous Glycerol Photoreforming

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    Several biochars were synthesized from olive stones and used as supports for TiO2, as an active semiconductor, and Pt as a co-catalyst (Pt/TiO2-PyCF and Pt/TiO2-AC). A third carbon-supported photocatalyst was prepared from commercial mesoporous carbon (Pt/TiO2-MCF). Moreover, a Pt/TiO2 solid based on Evonik P25 was used as a reference. The biochars used as supports transferred, to a large extent, their physical and chemical properties to the final photocatalysts. The synthesized catalysts were tested for hydrogen production from aqueous glycerol photoreforming. The results indicated that a mesoporous nature and small particle size of the photocatalyst lead to better H2 production. The analysis of the operational reaction conditions revealed that the H2 evolution rate was not proportional to the mass of the photocatalyst used, since, at high photocatalyst loading, the hydrogen production decreased because of the light scattering and reflection phenomena that caused a reduction in the light penetration depth. When expressed per gram of TiO2, the activity of Pt/TiO2-PyCF is almost 4-times higher than that of Pt/TiO2 (1079 and 273 mmol H2/gTiO2, respectively), which points to the positive effect of an adequate dispersion of a TiO2 phase on a carbonaceous support, forming a highly dispersed and homogeneously distributed titanium dioxide phase. Throughout a 12 h reaction period, the H2 production rate progressively decreases, while the CO2 production rate increases continuously. This behavior is compatible with an initial period when glycerol dehydrogenation to glyceraldehyde and/or dihydroxyacetone and hydrogen predominates, followed by a period in which comparatively slower C-C cleavage reactions begin to occur, thus generating both H2 and CO2

    Feasibility and results of an intensive cardiac rehabilitation program. Insights from the MxM (MĂĄs por Menos) randomized trial.

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    Cardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients' physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and non-ST-segment elevation acute coronary syndrome through the MĂĄs por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). In this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. A total of 497 patients (mean age, 57.8±10.0 years; 87.3% men) were finally assessed (intensive: n=262; standard: n=235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by ≄ 1 MET in ≄ 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. Intensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers. Registered at ClinicalTrials.gov (Identifier: NCT02619422)

    Feasibility and results of an intensive cardiac rehabilitation program. Insights from the MxM (MĂĄs por Menos) randomized trial

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    Introduccion y objetivos: Los programas de rehabilitacion cardiaca (PRC) engloban intervenciones encaminadas a mejorar el pronostico de la enfermedad cardiovascular influyendo en la condicin fısica, mental y social de los pacientes, pero no se conoce su duracion optima. Nuestro objetivo es comparar los resultados de un PRC estandar frente a otro intensivo mas breve tras un sındrome coronario agudo, mediante el estudio Mas por Menos. Metodos: Diseño prospectivo, aleatorizado, abierto, enmascarado a los evaluadores de eventos y multicentrico (PROBE). Se aleatorizoa los pacientes al PRC estandar de 8 semanas u otro intensivo de 2 semanas con sesiones de refuerzo. Se realizo una visita final 12 meses despues, tras la finalizacion del programa. Se evaluo: adherencia a la dieta, esfera psicologica, habito tabaquico, tratamiento farmacologico, capacidad funcional, calidad de vida, parametros cardiometabolicos y antropometricos, eventos cardiovasculares y mortalidad por cualquier causa durante el seguimiento. Resultados: Se analizoa 497 pacientes (media de edad, 57,8 10,0 an ̃ os; el 87,3% varones; programa intensivo, n = 262; estandar, n = 235). Las caracteristicas basales de ambos grupos eran similares. Al año, mas del 93% habıa mejorado en al menos 1 MET el resultado de la ergometrĂ­a. AdemĂĄs, la adherencia a la dieta mediterranea y la calidad de vida mejoraron significativamente con el PRC, sin diferencias significativas entre grupos. Los eventos cardiovasculares ocurrieron de manera similar en ambos grupos. Conclusiones: La PRC intensiva podrıa ser tan efectiva como la PRC estĂĄndar en lograr la adherencia a las medidas de prevencio n secundaria y ser una alternativa para algunos pacientes y centros.Introduction and objectives: Cardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients’ physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and non–ST- segment elevation acute coronary syndrome through the Ma ́s por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). Methods: In this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. Results: A total of 497 patients (mean age, 57.8 10.0 years; 87.3% men) were finally assessed (intensive: n = 262; standard: n = 235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by 1 MET in 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. Conclusions: Intensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers

    Comparative Safety and Effectiveness of Ticagrelor versus Clopidogrel in Patients With Acute Coronary Syndrome: An On-Treatment Analysis From a Multicenter Registry.

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    The net clinical benefit of ticagrelor over clopidogrel in acute coronary syndrome (ACS) has recently been questioned by observational studies which did not account for time-dependent confounders. We aimed to assess the comparative safety and effectiveness of ticagrelor vs. clopidogrel accounting for non-adherence in a real-life setting. This is a prospective, multicenter cohort study of patients with ACS discharged on ticagrelor or clopidogrel between 2015 and 2019. Major exclusions were previous intracranial bleeding, and the use of prasugrel or oral anticoagulation. Association of P2Y12 inhibitor therapy with 1-year risk of Bleeding Academic Research Consortium Type 3 or 5 bleeding; major adverse cardiac events (MACEs), a composite endpoint of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, or urgent target lesion revascularization; definite/probable stent thrombosis; vascular death; and net adverse clinical event (a composite endpoint of major bleeding and MACE) were analyzed according to the "on-treatment" principle, using fully adjusted Cox and Fine-Gray regression models with doubly robust inverse probability of censoring weighted estimators. Among 2,070 patients (mean age 63 years, 27% women, 62.5% ST-elevation MI), 1,035 were discharged on ticagrelor and clopidogrel, respectively. Ticagrelor-treated patients were younger and had few comorbidities, but high rates of medication non-compliance, compared with clopidogrel users. After comprehensive multivariate adjustments, ticagrelor did not increase the risk of major bleeding compared with clopidogrel [subhazard ratio, 1.40; 95% confidence interval (CI), 0.96-2.05], while proved superior in reducing MACE (hazard ratio 0.62; 95% CI, 0.43-0.90), vascular death (subhazard ratio, 0.71; 95% CI, 0.52-0.97) and definite/probable stent thrombosis (subhazard ratio, 0.54; 95% CI, 0.30-0.79); thereby resulting in a favorable net clinical benefit (hazard ratio 0.78; 95% CI, 0.60-0.98) compared with clopidogrel. Results from sensitivity analyses were consistent with those from the primary analysis, whereas those from the intention-to-treat (ITT) analysis went in the opposite direction. Among all-comers with ACS, ticagrelor did not significantly increase the risk of major bleeding, while resulting in a net clinical benefit compared with clopidogrel. Further research is warranted to confirm these findings in high bleeding risk populations. (ClinicalTrials.gov Identifier: NCT02500290); Current pre-specified analysis (ClinicalTrials.gov Identifier: NCT04630288)

    Mavacamten for treatment of symptomatic obstructive hypertrophic cardiomyopathy (EXPLORER-HCM): a randomised, double-blind, placebo-controlled, phase 3 trial

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    Apolipoprotein B, Residual Cardiovascular Risk After Acute Coronary Syndrome, and Effects of Alirocumab.

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    Background: Apolipoprotein B (apoB) provides an integrated measure of atherogenic risk. Whether apoB levels and apoB lowering hold incremental predictive information on residual risk after acute coronary syndrome beyond that provided by low-density lipoprotein cholesterol is uncertain. Methods: The ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) compared the proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome and elevated atherogenic lipoproteins despite optimized statin therapy. Primary outcome was major adverse cardiovascular events (MACE; coronary heart disease death, nonfatal myocardial infarction, fatal/nonfatal ischemic stroke, hospitalization for unstable angina). Associations between baseline apoB or apoB at 4 months and MACE were assessed in adjusted Cox proportional hazards and propensity score–matched models. Results: Median follow-up was 2.8 years. In proportional hazards analysis in the placebo group, MACE incidence increased across increasing baseline apoB strata (3.2 [95% CI, 2.9–3.6], 4.0 [95% CI, 3.6–4.5], and 5.5 [95% CI, 5.0–6.1] events per 100 patient-years in strata 35–<50, and ≀35 mg/dL, respectively). Compared with propensity score–matched patients from the placebo group, treatment hazard ratios for alirocumab also decreased monotonically across achieved apoB strata. Achieved apoB was predictive of MACE after adjustment for achieved low-density lipoprotein cholesterol or non–high-density lipoprotein cholesterol but not vice versa. Conclusions: In patients with recent acute coronary syndrome and elevated atherogenic lipoproteins, MACE increased across baseline apoB strata. Alirocumab reduced MACE across all strata of baseline apoB, with larger absolute reductions in patients with higher baseline levels. Lower achieved apoB was associated with lower risk of MACE, even after accounting for achieved low-density lipoprotein cholesterol or non–high-density lipoprotein cholesterol, indicating that apoB provides incremental information. Achievement of apoB levels as low as ≀35 mg/dL may reduce lipoprotein-attributable residual risk after acute coronary syndrome. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01663402.gov; Unique identifier: NCT01663402.URL: https://www
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