Concentration Dependence of Superconductivity and Order-Disorder Transition in the Hexagonal Rubidium Tungsten Bronze RbxWO3. Interfacial and bulk properties

We revisited the problem of the stability of the superconducting state in RbxWO3 and identified the main causes of the contradictory data previously published. We have shown that the ordering of the Rb vacancies in the nonstoichiometric compounds have a major detrimental effect on the superconducting temperature Tc.The order-disorder transition is first order only near x = 0.25, where it cannot be quenched effectively and Tc is reduced below 1K. We found that the high Tc's which were sometimes deduced from resistivity measurements, and attributed to compounds with .25 < x < .30, are to be ascribed to interfacial superconductivity which generates spectacular non-linear effects. We also clarified the effect of acid etching and set more precisely the low-rubidium-content boundary of the hexagonal phase.This work makes clear that Tc would increase continuously (from 2 K to 5.5 K) as we approach this boundary (x = 0.20), if no ordering would take place - as its is approximately the case in CsxWO3. This behaviour is reminiscent of the tetragonal tungsten bronze NaxWO3 and asks the same question : what mechanism is responsible for this large increase of Tc despite the considerable associated reduction of the electron density of state ? By reviewing the other available data on these bronzes we conclude that the theoretical models which are able to answer this question are probably those where the instability of the lattice plays a major role and, particularly, the model which call upon local structural excitations (LSE), associated with the missing alkali atoms.Comment: To be published in Physical Review

Sorafenib for advanced and refractory desmoid tumors

BACKGROUND Desmoid tumors (also referred to as aggressive fibromatosis) are connective tissue neoplasms that can arise in any anatomical location and infiltrate the mesentery, neurovascular structures, and visceral organs. There is no standard of care. METHODS In this double-blind, phase 3 trial, we randomly assigned 87 patients with progressive, symptomatic, or recurrent desmoid tumors to receive either sorafenib (400- mg tablet once daily) or matching placebo. Crossover to the sorafenib group was permitted for patients in the placebo group who had disease progression. The primary end point was investigator-assessed progression-free survival; rates of objective response and adverse events were also evaluated. RESULTS With a median follow-up of 27.2 months, the 2-year progression-free survival rate was 81% (95% confidence interval [CI], 69 to 96) in the sorafenib group and 36% (95% CI, 22 to 57) in the placebo group (hazard ratio for progression or death, 0.13; 95% CI, 0.05 to 0.31; P<0.001). Before crossover, the objective response rate was 33% (95% CI, 20 to 48) in the sorafenib group and 20% (95% CI, 8 to 38) in the placebo group. The median time to an objective response among patients who had a response was 9.6 months (interquartile range, 6.6 to 16.7) in the sorafenib group and 13.3 months (interquartile range, 11.2 to 31.1) in the placebo group. The objective responses are ongoing. Among patients who received sorafenib, the most frequently reported adverse events were grade 1 or 2 events of rash (73%), fatigue (67%), hypertension (55%), and diarrhea (51%). CONCLUSIONS Among patients with progressive, refractory, or symptomatic desmoid tumors, sorafenib significantly prolonged progression-free survival and induced durable responses

Serum uric acid, influence of sacubitril/valsartan, and cardiovascular outcomes in heart failure with preserved ejection fraction: PARAGON-HF

Abstract Background Serum uric acid (SUA) is a biomarker of several pathobiologies relevant to the pathogenesis of heart failure with preserved ejection fraction (HFpEF), though by itself may also worsen outcomes. In HF with reduced EF, SUA is independently associated with adverse outcomes and sacubitril/valsartan reduces SUA compared to enalapril. These effects in HFpEF have not been delineated. Purpose To determine the prognostic value of SUA, relationship of change in SUA to quality of life and outcomes, and influence of sacubitril/valsartan on SUA in HFpEF. Methods We analyzed 4,795 participants from the Prospective Comparison of ARNI with ARB Global Outcomes in HF with Preserved Ejection Fraction (PARAGON-HF) trial. We related baseline hyperuricemia to the primary outcome (CV death and total HF hospitalization), its components, myocardial infarction or stroke, and a renal composite outcome. At the 4-month visit, the relationship between SUA change and Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS) and several biomarkers including N-terminal pro-B-type natriuretic peptide (NT-proBNP) were also assessed. We simultaneously adjusted for baseline and time-updated SUA to determine whether lowering SUA was associated with clinical benefit. Results Average age was 73±8 years and 52% were women. After multivariable adjustment, hyperuricemia was associated with increased risk for most outcomes (primary outcome HR 1.61, 95% CI 1.37, 1.90, Fig 1A). The treatment effect of sacubitril/valsartan for the primary outcome was not modified by baseline SUA (interaction p=0.11). Sacubitril/valsartan reduced SUA −0.38 mg/dL (95% CI: −0.45, −0.31) compared with valsartan (Fig 1B), with greater effect in those with baseline hyperuricemia (−0.50 mg/dL) (interaction p=0.013). Change in SUA was independently and inversely associated with change in KCCQ-OSS (p=0.019) and eGFR (p&amp;lt;0.001), but not NT-proBNP (p=0.52). Time-updated SUA was a stronger predictor of adverse outcomes over baseline SUA. Conclusions SUA independently predicts adverse outcomes in HFpEF. Sacubitril/valsartan significantly reduces SUA compared to valsartan, an effect that was stronger in those with higher baseline SUA, and reducing SUA was associated with improved outcomes. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Novartis </jats:sec

Effects of Sacubitril/Valsartan on All-Cause Hospitalizations in Heart Failure: Post Hoc Analysis of the PARADIGM-HF and PARAGON-HF Randomized Clinical Trials.

Sacubitril/valsartan is indicated to reduce the risk of cardiovascular death and heart failure (HF) hospitalizations in patients with chronic HF. However, many of these patients are older and have multiple comorbidities that increase the risk of hospitalization for causes other than HF. To assess the effects of sacubitril/valsartan on hospitalizations of any cause across the spectrum of left ventricular ejection fraction (LVEF). This post hoc, participant-level, pooled analysis of the PARADIGM-HF (in patients with an LVEF ≤40%) and PARAGON-HF (in patients with an LVEF ≥45%) randomized clinical trials was conducted from February 5, 2024, to April 5, 2024. Participants with chronic HF, New York Heart Association classes II through IV symptoms, and elevated natriuretic peptides were randomized to treatment with either sacubitril/valsartan or a renin-angiotensin system inhibitor (RASi)-enalapril in the PARADIGM-HF trial or valsartan in the PARAGON-HF trial. Sacubitril/valsartan vs RASi (enalapril or valsartan). The effects of sacubitril/valsartan on time to first investigator-reported all-cause and cause-specific hospitalizations were examined using Cox proportional hazards models, stratified by geographic region and trial. Effect modification by LVEF as a continuous function was examined. Among 13 194 participants in the PARADIGM-HF and PARAGON-HF trials, mean (SD) patient age was 67 (11) years, 8883 patients (67.3%) were male, and mean (SD) LVEF was 40% (15%). Sacubitril/valsartan significantly reduced the risk of all-cause hospitalization (ACH) compared with RASi over a median (IQR) follow-up period of 2.5 (1.8-3.1) years (hazard ratio [HR], 0.92; 95% CI, 0.88-0.97; P = .002). The incidence rate of first ACH was 25 (95% CI, 24-26) per 100 patient-years in the sacubitril/valsartan arm and 27 (95% CI, 26-28) per 100 patient-years in the RASi arm. The absolute risk reduction (ARR) was 2.1 per 100 patient-years, corresponding to a number needed to treat (NNT) of 48 patient-years of treatment exposure to prevent 1 ACH. Reductions in overall hospitalizations seemed primarily driven by lower rates of cardiac and pulmonary hospitalizations with sacubitril/valsartan. Patients in the 2 treatment arms had similar rates of composite noncardiac hospitalizations. Treatment heterogeneity on ACH by LVEF was observed (P for interaction = .03), with benefits most apparent in patients with an LVEF less than 60% (HR, 0.91; 95% CI, 0.86-0.96), but not in patients with an LVEF of 60% or more (HR, 0.97; 95% CI, 0.86-1.09). In this post hoc pooled analysis of 13 194 patients with chronic HF in the PARADIGM-HF and PARAGON-HF randomized clinical trials, sacubitril/valsartan significantly reduced hospitalization for any reason, with benefits most apparent in patients with an LVEF below normal. This reduction appeared to be principally driven by lower rates of cardiac and pulmonary hospitalizations. ClinicalTrials.gov Identifiers: NCT01035255 (PARADIGM-HF) and NCT01920711 (PARAGON-HF)