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1.
JACC Clin Electrophysiol ; 10(5): 916-926, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38520434

RESUMEN

BACKGROUND: Past clinical trials have shown the benefit of implantable cardioverter-defibrillators (ICDs) for reducing sudden cardiac death in at-risk patients. However, heart failure management and ICD technology have changed since these trials were first published. An updated assessment of ICD mortality benefit is needed. OBJECTIVES: The purpose of this study was to compare mortality rates between patients with a primary prevention (PP) indication for an ICD who did or did not receive an ICD using a contemporary, real-world data set. METHODS: Data was obtained from a large electronic health record data set covering patients in the United States from 2012 through 2020 who had a PP indication for an ICD and survived at least 1-year postindication. RESULTS: A total of 25,296 patients were identified as having a PP indication for ICD implantation, of which 2,118 (8.4%) were treated with an ICD within a year. Treated patients were younger than nontreated patients (age 63.4 years vs 66.1 years) with a smaller proportion of women (25.0% vs 36.7%). After 4-to-1 propensity matching, treated patients had similar clinical characteristics to nontreated patients. A Cox proportional hazard model estimated a 24.3% lower risk of all-cause mortality in patients when treated vs not treated with an ICD (HR: 0.757; 95% CI: 0.678-0.835; P <0.001). There was no detectable difference in ICD benefit between patients with ischemic and nonischemic heart disease (P = 0.50). CONCLUSIONS: ICD treatment of patients with a PP indication is associated with improved mortality even in the context of evolving adjunctive HF treatment, consistent with earlier landmark trials.


Asunto(s)
Muerte Súbita Cardíaca , Desfibriladores Implantables , Insuficiencia Cardíaca , Prevención Primaria , Humanos , Desfibriladores Implantables/estadística & datos numéricos , Femenino , Masculino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/terapia , Persona de Mediana Edad , Anciano , Muerte Súbita Cardíaca/prevención & control , Muerte Súbita Cardíaca/epidemiología , Estados Unidos/epidemiología , Estudios Retrospectivos
2.
ACS Appl Mater Interfaces ; 10(29): 24784-24790, 2018 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-29952556

RESUMEN

Metal organic framework (MOF)/polymer composite membranes are of interest for gas separations, as they often have performance that exceeds the neat polymer. However, traditional composite membranes, known as mixed matrix membranes (MMMs), can have complex and time-consuming preparation procedures. The MOF and polymer are traditionally prepared separately and require priming and mixing to ensure uniform distribution of particles and compatibility of the polymer-particle interface. In this study, we reduce the number of steps using an in situ MOF growth strategy. Herein, MMMs are prepared by growing MOF (UiO-66) in situ within a Matrimid polymer matrix while simultaneously curing the matrix. The gas separation performance for MMMs, prepared using this approach, was evaluated for the CO2/N2 separation and compared with MMMs made using the traditional postsynthesis mixing. It was found that MMMs prepared using both the in situ MOF growth strategy and by traditional postsynthesis mixing are equivalent in performance. However, using the in situ MOF growth allows for a simpler, faster, and potentially more economical fabrication alternative for MMMs.

3.
ACS Appl Mater Interfaces ; 9(7): 5678-5682, 2017 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-28177225

RESUMEN

We have utilized an environmentally friendly synthesis approach for the accelerated growth of a selective inorganic membrane on a polymeric hollow fiber support for postcombustion carbon capture. Specifically, continuous defect-free ZIF-8 thin films were grown and anchored using continuous flow synthesis on the outer surface of porous supports using water as solvent. These membranes demonstrated CO2 permeance of 22 GPU and the highest reported CO2/N2 selectivity of 52 for a continuous flow synthesized ZIF-8 membrane.

4.
Chem Commun (Camb) ; 52(79): 11768-11771, 2016 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-27722238

RESUMEN

This study presents the fabrication of a new mixed matrix membrane using two microporous polymers: a polymer of intrinsic microporosity PIM-1 and a benzimidazole linked polymer, BILP-101, and their CO2 separation properties from post-combustion flue gas. 17, 30 and 40 wt% loadings of BILP-101 into PIM-1 were tested, resulting in mechanically stable films showing very good interfacial interaction due to the inherent H-bonding capability of the constituent materials. Gas transport studies showed that BILP-101/PIM-1 membranes exhibit high CO2 permeability (7200 Barrer) and selectivity over N2 (15). The selected hybrid membrane was further tested for CO2 separation using actual flue gas from a coal-fired power plant.

5.
Chem Commun (Camb) ; 51(69): 13393-6, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26214758

RESUMEN

Rational design concepts were used to prepare a novel porous benzimidazole-linked polymer (BILP-101) in a simple one-pot reaction. BILP-101 has exhibited ultra-microporosity (0.54 nm), very high CO2 uptake (∼1 mmol g(-1), 4 wt%, 0.15 bar/298 K) and exceptional CO2/N2 selectivity of 80 (298 K), which results in remarkable working capacity and regenerability for CO2 capture applications.

6.
J Nat Prod ; 76(10): 1966-9, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24074257

RESUMEN

In an effort to generate new steroidal aromatase inhibitors, formestane (4-hydroxyandrost-4-ene-3,17-dione) (1) was biotransformed by Rhizopus oryzae to yield the known 4ß,5α-dihydroxyandrostane-3,17-dione as the major product (5) and bioconverted by Beauveria bassiana to afford the known reduced 4,17ß-dihydroxyandrost-4-en-3-one (6) and 3α,17ß-dihydroxy-5ß-androstan-4-one (7) and the new 4,11α,17ß-trihydroxyandrost-4-en-3-one (8). All the metabolites showed more potent activities than their parent congener in the aromatase and MCF-7 breast cancer assays. The bioactivities and structural elucidation of these metabolites as well as the semisynthesis of formestane (1) from testosterone (2) are reported herein.


Asunto(s)
Androstenodiona/análogos & derivados , Inhibidores de la Aromatasa/síntesis química , Inhibidores de la Aromatasa/farmacología , Beauveria/metabolismo , Androstenodiona/síntesis química , Androstenodiona/química , Androstenodiona/metabolismo , Inhibidores de la Aromatasa/química , Biotransformación , Neoplasias de la Mama , Femenino , Humanos , Estereoisomerismo , Testosterona/síntesis química , Testosterona/química , Testosterona/metabolismo
7.
Langmuir ; 29(19): 5927-36, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23594169

RESUMEN

Oriented thin films of a flexible, luminescent, metal organic framework (MOF), [Zn2(bpdc)2(bpee)·2DMF] (bpdc = 4,4'-biphenyldicarboxylate; bpee = 1,2-bipyridylethylene), also known as RPM3, were prepared on glass via pulsed laser deposition (PLD) followed by a solvothermal treatment. RPM3 thin films were then functionalized with AgNO3 by forming a π complex with the bpee linker. The reversible binding of olefins such as propylene and 1-hexene to the Ag(+) functionalized RPM3 thin film was monitored by fluorescence spectroscopy. Adsorption of the olefins resulted in a fluorescence enhancement, while the corresponding paraffins either did not change or partially quenched the fluorescence. The RPM3 thin films hold promise as olefin sensors or adsorbents for olefin/paraffin separations.


Asunto(s)
Alquenos/análisis , Complejos de Coordinación/química , Compuestos Organometálicos/química , Plata/química , Modelos Moleculares , Tamaño de la Partícula , Propiedades de Superficie , Zinc/química
8.
J Am Chem Soc ; 134(37): 15201-4, 2012 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-22946693

RESUMEN

Separation of hydrocarbons is one of the most energy demanding processes. The need to develop materials for the selective adsorption of hydrocarbons, under reasonable conditions, is therefore of paramount importance. This work unveils unexpected hydrocarbon selectivity in a flexible Metal-Organic Framework (MOF), based on differences in their gate opening pressure. We show selectivity dependence on both chain length and specific framework-gas interaction. By combining Raman spectroscopy and theoretical van der Waals Density Functional (vdW-DF) calculations, the separation mechanisms governing this unexpected gate-opening behavior are revealed.


Asunto(s)
Hidrocarburos/aislamiento & purificación , Metales/química , Compuestos Orgánicos/química , Adsorción , Espectrometría Raman
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