Propiedades físico químicas de dos selladores a base de resina epóxica: Topseal y Adseal. Estudio comparativo

Resumen El objetivo del estudio fue evaluar la radiopacidad, solubilidad, fluidez y espesor de la película de dos selladores a base de resina epóxica: Topseal y Adseal. Metodología: Se realizaron pruebas físicas según los requisitos de la norma ISO 6876:2012. La radiopacidad fue medida utilizando 5 discos de 10mm de diámetro x 1mm de espesor de cada sellador y una cuña de aluminio con pasos igualmente situados de 0,8mm; se tomaron radiografías digitales de los 5 discos del mismo material junto con la cuña de aluminio a diferentes tiempos de exposición, analizándolas con el software ImageJ. Para la solubilidad se crearon 10 discos de 20mm de diámetro x 1,5mm de espesor de cada sellador, se agruparon parejas del mismo sellador en cajas de Petri pesadas previamente, realizando cinco ensayos por cada uno; las cajas de Petri fueron nuevamente pesadas al fin del experimento, registrando la diferencia con una precisión de 0,001g. Para el análisis de fluidez los selladores se colocaron entre 2 placas de vidrio bajo un peso de 120 g por 10 minutos, los diámetros de los discos formados se midieron con el software imageJ; la prueba se repitió 5 veces para cada sellador. Para el análisis de espesor de película los selladores se colocaron entre 2 placas de vidrio bajo una carga de 150N por 10 minutos, se tomaron medidas del espesor de las dos placas de vidrio con un estereomicroscopio previo a la aplicación del sellador y luego de aplicar la carga, repitiendo la prueba 5 veces para cada sellador. Resultados: Radiopacidad: Se encontró una diferencia estadísticamente significativa entre el Topseal y el Adseal con valores de 9,6mm y 2,4mm respectivamente, presentando mayor radiopacidad el Topseal. Solubilidad: No se encontró diferencias estadísticamente significativas entre el peso inicial y final de ambos selladores, resultando en la no presencia de solubilidad en las primeras 24 horas. Fluidez: Se encontró una diferencia estadísticamente significativa entre el Topseal y el Adseal con valores de 19,72 mm y 27,89 mm respectivamente, encontrando mayor fluidez en el Adseal. Espesor de película: No se encontró una diferencia estadísticamente significativa entre el Topseal y el Adseal. Conclusiones: De las propiedades analizadas en este estudio, solamente se encontró diferencia estadísticamente significativa en la radiopacidad y fluidez, siendo el Topseal el de mayor radiopacidad y el Adseal el de mayor fluidez.Abstract. The purpose of these study was to evaluate the radiopacity, solubility, flow and film thickness of two Epoxy Resin-based sealers: Topseal and Adseal. Methodology: Physical tests were realized according to the requirements under the ISO Standards 6876:2012. The radiopacity was measured using 5 specimens of 10mm diameter x 1mm thickness for each sealer and one aluminum step wedge equally situated of 0,8mm, along with digital radiographies of the 5 specimens for the same material and the aluminum step wedge with different exposure times, analyzing them with Software ImageJ. For solubility, 10 specimens of 20mm diameter and 1,5mm thickness were crated for each sealer, pairs from the same sealer in Petri Plates previously weighted were grouped, realizing five essays for each one; Petri plates were weighted again at the end of the experiment, registering the difference with an accuracy of 0,001g. For the flow analysis the sealers were placed between 2 glass slides under a 120g weight during 10 minutes, in which the specimens’ diameter were measured with ImageJ software, repeating the test 5 times for each sealer. For the film thickness analysis, the sealers were placed between 2 glass slides under a charge of 150N during 10 minutes, taking measures for the thickness of both glass slides with a stereomicroscope before the application of the sealer and after the charge, repeating the test 5 times for each sealer. Results: Radiopacity: a statistical significance difference was found between Topseal and Adseal with values of 9,6mm and 2,4mm, respectively, in which Topseal registered a higher raiopacity. Solubility: No statistical significance differences were found between the initial and final weight of both sealers, which meant that no solubility presence was registered for the first 24 hours. Flow: a statistical significance difference was found between Topseal and Adseal with values of 19,72 mm and 27,89 mm, respectively, in which Adseal registered a higher flow. Film Thickness: No statistical significance differences were found between Topseal and Adseal. Conclusions: From the properties analyzed in this study, a statistical significance difference was found only for radiopacity and flow, in which Topseal registered the higher radiopacity, and Adseal the higher flow.Maestrí

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Cardiac myosin activation with omecamtiv mecarbil in systolic heart failure

BACKGROUND The selective cardiac myosin activator omecamtiv mecarbil has been shown to improve cardiac function in patients with heart failure with a reduced ejection fraction. Its effect on cardiovascular outcomes is unknown. METHODS We randomly assigned 8256 patients (inpatients and outpatients) with symptomatic chronic heart failure and an ejection fraction of 35% or less to receive omecamtiv mecarbil (using pharmacokinetic-guided doses of 25 mg, 37.5 mg, or 50 mg twice daily) or placebo, in addition to standard heart-failure therapy. The primary outcome was a composite of a first heart-failure event (hospitalization or urgent visit for heart failure) or death from cardiovascular causes. RESULTS During a median of 21.8 months, a primary-outcome event occurred in 1523 of 4120 patients (37.0%) in the omecamtiv mecarbil group and in 1607 of 4112 patients (39.1%) in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI], 0.86 to 0.99; P = 0.03). A total of 808 patients (19.6%) and 798 patients (19.4%), respectively, died from cardiovascular causes (hazard ratio, 1.01; 95% CI, 0.92 to 1.11). There was no significant difference between groups in the change from baseline on the Kansas City Cardiomyopathy Questionnaire total symptom score. At week 24, the change from baseline for the median N-terminal pro-B-type natriuretic peptide level was 10% lower in the omecamtiv mecarbil group than in the placebo group; the median cardiac troponin I level was 4 ng per liter higher. The frequency of cardiac ischemic and ventricular arrhythmia events was similar in the two groups. CONCLUSIONS Among patients with heart failure and a reduced ejection, those who received omecamtiv mecarbil had a lower incidence of a composite of a heart-failure event or death from cardiovascular causes than those who received placebo. (Funded by Amgen and others; GALACTIC-HF ClinicalTrials.gov number, NCT02929329; EudraCT number, 2016 -002299-28.)