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1.
Proc Natl Acad Sci U S A ; 120(31): e2306046120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487099

RESUMEN

The electron-conducting circuitry of life represents an as-yet untapped resource of exquisite, nanoscale biomolecular engineering. Here, we report the characterization and structure of a de novo diheme "maquette" protein, 4D2, which we subsequently use to create an expanded, modular platform for heme protein design. A well-folded monoheme variant was created by computational redesign, which was then utilized for the experimental validation of continuum electrostatic redox potential calculations. This demonstrates how fundamental biophysical properties can be predicted and fine-tuned. 4D2 was then extended into a tetraheme helical bundle, representing a 7 nm molecular wire. Despite a molecular weight of only 24 kDa, electron cryomicroscopy illustrated a remarkable level of detail, indicating the positioning of the secondary structure and the heme cofactors. This robust, expressible, highly thermostable and readily designable modular platform presents a valuable resource for redox protein design and the future construction of artificial electron-conducting circuitry.


Asunto(s)
Hemoproteínas , Biofisica , Microscopía por Crioelectrón , Electrones , Oxidación-Reducción
2.
J Am Coll Cardiol ; 76(1): 128, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32616155
3.
Ann Intern Med ; 150(7): 490-2, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19258548

RESUMEN

Healthcare Professionals for Healthcare Reform is a group of physicians and others interested in health care reform who, recognizing the urgent need for change, convened to propose a universal health care plan that builds on the strengths of the U.S. health care system and improves on its coverage, efficiency, and capacity for patient choice. The group proposes a tiered plan, the core of which (Tier 1) would be lifetime, basic, publicly funded coverage for the entire population on the basis of the best evidence about which therapies are considered life saving, life-sustaining, or preventive. Optional coverage (Tier 2) would be funded by private insurance and cover all therapies considered to help with quality of life and functional impairment. Items considered to be luxury or cosmetic (Tier 3) would generally not be covered, as is the case under the current system. The entire system would be overseen by a quasi-governmental, largely independent organization known as "The Board," which would resemble the Federal Reserve and interact with U.S. Department of Health and Human Services agencies to oversee implementation and coverage. By building on the current health care system while introducing other features and efficiencies, the Expanding Medical and Behavioral Resources with Access to Care for Everyone (EMBRACE) plan for universal health insurance coverage offers several advantages over alternative plans that have been proposed.


Asunto(s)
Reforma de la Atención de Salud/organización & administración , Accesibilidad a los Servicios de Salud/organización & administración , Cobertura Universal del Seguro de Salud/organización & administración , Financiación Gubernamental , Regulación Gubernamental , Reforma de la Atención de Salud/economía , Accesibilidad a los Servicios de Salud/economía , Humanos , Aseguradoras/economía , Política , Estados Unidos , Cobertura Universal del Seguro de Salud/economía
4.
Ann Biomed Eng ; 31(6): 667-77, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12797616

RESUMEN

A bioresorbable, expandable poly(L-lactic acid) stent has been designed, based on a linear, continuous coil array principle, by which multiple furled lobes convert to a single lobe upon balloon expansion, without heating. Stent strength and compliance are sufficient to permit deployment by a conventional balloon angioplasty catheter. Several multiple lobe configurations were investigated, with expansion ratios ranging from 1.4 to 1.9 and expanded diameters ranging from 2.3 to 4.7 mm. Compression resistance of the expanded stent is dependent on fiber coil density and fiber ply. A range sufficient for endovascular service was obtained, with less than 4% elastic recoil in six day saline incubation studies. Surface plasma treatment with di(ethylene glycol) vinyl ether significantly reduced platelet adhesion in a 1 h porcine arteriovenous shunt model. Patency was maintained in one week implant studies in the porcine common femoral artery. However, a strong inflammatory response, and significant reduction of the vascular lumen were observed following two weeks implantation. The design principles and fabrication techniques for this bioresorbable stent are sufficiently versatile that a broad range of applications can be addressed. Much work remains to be done, including long-term evaluation of the inflammatory response, and of polymer degradation. The results of this study demonstrate the feasibility of expandable biodegradable stent design and deployment by conventional means.


Asunto(s)
Implantes Absorbibles , Prótesis Vascular/efectos adversos , Arteria Femoral/patología , Arteria Femoral/cirugía , Infecciones Relacionadas con Prótesis/etiología , Stents/efectos adversos , Animales , Presión Sanguínea , Materiales Biocompatibles Revestidos/efectos adversos , Materiales Biocompatibles Revestidos/síntesis química , Elasticidad , Análisis de Falla de Equipo/métodos , Glicoles de Etileno/efectos adversos , Arteria Femoral/fisiopatología , Ácido Láctico , Movimiento (Física) , Activación Plaquetaria , Poliésteres , Polímeros , Diseño de Prótesis , Falla de Prótesis , Infecciones Relacionadas con Prótesis/patología , Porcinos , Compuestos de Vinilo/efectos adversos
5.
JAMA ; 288(6): 701-9, 2002 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-12169073

RESUMEN

CONTEXT: Major depressive disorder (MDD) occurs in 15% to 23% of patients with acute coronary syndromes and constitutes an independent risk factor for morbidity and mortality. However, no published evidence exists that antidepressant drugs are safe or efficacious in patients with unstable ischemic heart disease. OBJECTIVE: To evaluate the safety and efficacy of sertraline treatment of MDD in patients hospitalized for acute myocardial infarction (MI) or unstable angina and free of other life-threatening medical conditions. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled trial conducted in 40 outpatient cardiology centers and psychiatry clinics in the United States, Europe, Canada, and Australia. Enrollment began in April 1997 and follow-up ended in April 2001. PATIENTS: A total of 369 patients with MDD (64% male; mean age, 57.1 years; mean 17-item Hamilton Depression [HAM-D] score, 19.6; MI, 74%; unstable angina, 26%). INTERVENTION: After a 2-week single-blind placebo run-in, patients were randomly assigned to receive sertraline in flexible dosages of 50 to 200 mg/d (n = 186) or placebo (n = 183) for 24 weeks. MAIN OUTCOME MEASURES: The primary (safety) outcome measure was change from baseline in left ventricular ejection fraction (LVEF); secondary measures included surrogate cardiac measures and cardiovascular adverse events, as well as scores on the HAM-D scale and Clinical Global Impression Improvement scale (CGI-I) in the total randomized sample, in a group with any prior history of MDD, and in a more severe MDD subgroup defined a priori by a HAM-D score of at least 18 and history of 2 or more prior episodes of MDD. RESULTS: Sertraline had no significant effect on mean (SD) LVEF (sertraline: baseline, 54% [10%]; week 16, 54% [11%]; placebo: baseline, 52% [13%]; week 16, 53% [13%]), treatment-emergent increase in ventricular premature complex (VPC) runs (sertraline: 13.1%; placebo: 12.9%), QTc interval greater than 450 milliseconds at end point (sertraline: 12%; placebo: 13%), or other cardiac measures. All comparisons were statistically nonsignificant (P> or = .05). The incidence of severe cardiovascular adverse events was 14.5% with sertraline and 22.4% with placebo. In the total randomized sample, the CGI-I (P =.049), but not the HAM-D (P =.14), favored sertraline. The CGI-I responder rates for sertraline were significantly higher than for placebo in the total sample (67% vs 53%; P =.01), in the group with at least 1 prior episode of depression (72% vs 51%; P =.003), and in the more severe MDD group (78% vs 45%; P =.001). In the latter 2 groups, both CGI-I and HAM-D measures were significantly better in those assigned to sertraline. CONCLUSION: Our results suggest that sertraline is a safe and effective treatment for recurrent depression in patients with recent MI or unstable angina and without other life-threatening medical conditions.


Asunto(s)
Angina Inestable/psicología , Trastorno Depresivo Mayor/tratamiento farmacológico , Infarto del Miocardio/psicología , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Sertralina/uso terapéutico , Trastorno Depresivo Mayor/etiología , Método Doble Ciego , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Sertralina/efectos adversos , Resultado del Tratamiento
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