1,411 research outputs found
An improved continuous compositional-spread technique based on pulsed-laser deposition and applicable to large substrate areas
A new method for continuous compositional-spread (CCS) thin-film fabrication
based on pulsed-laser deposition (PLD) is introduced. This approach is based on
a translation of the substrate heater and the synchronized firing of the
excimer laser, with the deposition occurring through a slit-shaped aperture.
Alloying is achieved during film growth (possible at elevated temperature) by
the repeated sequential deposition of sub-monolayer amounts. Our approach
overcomes serious shortcomings in previous in-situ implementations of CCS based
on sputtering or PLD, in particular the variations of thickness across the
compositional spread and the differing deposition energetics as function of
position. While moving-shutter techniques are appropriate for PLD-approaches
yielding complete spreads on small substrates (i.e. small as compared to
distances over which the deposition parameters in PLD vary, typically about 1
cm), our method can be used to fabricate samples that are large enough for
individual compositions to be analyzed by conventional techniques, including
temperature-dependent measurements of resistivity and dielectric and magnetic
and properties (i.e. SQUID magnetometry). Initial results are shown for spreads
of (Sr,Ca)RuO.Comment: 6 pages, 8 figures, accepted for publication in Rev. Sci. Instru
Baseline characteristics and treatment of patients in prospective comparison of ARNI with ACEI to determine impact on global mortality and morbidity in heart failure trial (PARADIGM-HF)
Aim<p></p>
To describe the baseline characteristics and treatment of the patients randomized in the PARADIGM-HF (Prospective comparison of ARNi with ACEi to Determine Impact on Global Mortality and morbidity in Heart Failure) trial, testing the hypothesis that the strategy of simultaneously blocking the renin–angiotensin–aldosterone system and augmenting natriuretic peptides with LCZ696 200 mg b.i.d. is superior to enalapril 10 mg b.i.d. in reducing mortality and morbidity in patients with heart failure and reduced ejection fraction.<p></p>
Methods<p></p>
Key demographic, clinical and laboratory findings, along with baseline treatment, are reported and compared with those of patients in the treatment arm of the Studies Of Left Ventricular Dysfunction (SOLVD-T) and more contemporary drug and device trials in heart failure and reduced ejection fraction.<p></p>
Results<p></p>
The mean age of the 8442 patients in PARADIGM-HF is 64 (SD 11) years and 78% are male, which is similar to SOLVD-T and more recent trials. Despite extensive background therapy with beta-blockers (93% patients) and mineralocorticoid receptor antagonists (60%), patients in PARADIGM-HF have persisting symptoms and signs, reduced health related quality of life, a low LVEF (mean 29 ± SD 6%) and elevated N-terminal-proB type-natriuretic peptide levels (median 1608 inter-quartile range 886–3221 pg/mL).<p></p>
Conclusion<p></p>
PARADIGM-HF will determine whether LCZ696 is more beneficial than enalapril when added to other disease-modifying therapies and if further augmentation of endogenous natriuretic peptides will reduce morbidity and mortality in heart failure and reduced ejection fractio
Variation in nomenclature of somatic variants for selection of oncological therapies:Can we reach a consensus soon?
A standardized nomenclature for reporting oncology biomarker variants is key to avoid misinterpretation of results and unambiguous registration in clinical databases. External quality assessment (EQA) schemes have revealed a need for more consistent nomenclature use in clinical genetics. We evaluated the propensity of EQA for improvement of compliance with Human Genome Variation Society (HGVS) recommendations for reporting of predictive somatic variants in lung and colorectal cancer. Variant entries between 2012 and 2018 were collected from written reports and electronic results sheets. In total, 4,053 variants were assessed, of which 12.1% complied with HGVS recommendations. Compliance improved over time from 2.1% (2012) to 22.3% (2018), especially when laboratories participated in multiple EQA schemes. Compliance was better for next-generation sequencing (20.9%) compared with targeted techniques (9.8%). In the 1792 reports, HGVS recommendations for reference sequences were met for 31.9% of reports, for 36.0% of noncommercial, and 26.5% of commercial test methods. Compliance improved from 16.7% (2012) to 33.1% (2018), and after repeated EQA participation. EQA participation improves compliance with HGVS recommendations. The residual percentage of errors in the most recent schemes suggests that laboratories, companies, and EQA providers need to collaborate for additional improvement of harmonization in clinical test reporting
Guidance for laboratories performing molecular pathology for cancer patients
Molecular testing is becoming an important part of the diagnosis of any patient with cancer. The challenge to laboratories is to meet this need, using reliable methods and processes to ensure that patients receive a timely and accurate report on which their treatment will be based. The aim of this paper is to provide minimum requirements for the management of molecular pathology laboratories. This general guidance should be augmented by the specific guidance available for different tumour types and tests. Preanalytical considerations are important, and careful consideration of the way in which specimens are obtained and reach the laboratory is necessary. Sample receipt and handling follow standard operating procedures, but some alterations may be necessary if molecular testing is to be performed, for instance to control tissue fixation. DNA and RNA extraction can be standardised and should be checked for quality and quantity of output on a regular basis. The choice of analytical method(s) depends on clinical requirements, desired turnaround time, and expertise available. Internal quality control, regular internal audit of the whole testing process, laboratory accreditation, and continual participation in external quality assessment schemes are prerequisites for delivery of a reliable service. A molecular pathology report should accurately convey the information the clinician needs to treat the patient with sufficient information to allow for correct interpretation of the result. Molecular pathology is developing rapidly, and further detailed evidence-based recommendations are required for many of the topics covered here
Coronary-artery bypass surgery in patients with ischemic cardiomyopathy
BACKGROUND
The survival benefit of a strategy of coronary-artery bypass grafting (CABG) added to
guideline-directed medical therapy, as compared with medical therapy alone, in patients
with coronary artery disease, heart failure, and severe left ventricular systolic
dysfunction remains unclear.
METHODS
From July 2002 to May 2007, a total of 1212 patients with an ejection fraction of 35%
or less and coronary artery disease amenable to CABG were randomly assigned to
undergo CABG plus medical therapy (CABG group, 610 patients) or medical therapy
alone (medical-therapy group, 602 patients). The primary outcome was death from any
cause. Major secondary outcomes included death from cardiovascular causes and death
from any cause or hospitalization for cardiovascular causes. The median duration of
follow-up, including the current extended-follow-up study, was 9.8 years.
RESULTS
A primary outcome event occurred in 359 patients (58.9%) in the CABG group and in
398 patients (66.1%) in the medical-therapy group (hazard ratio with CABG vs. medical
therapy, 0.84; 95% confidence interval [CI], 0.73 to 0.97; P=0.02 by log-rank test). A
total of 247 patients (40.5%) in the CABG group and 297 patients (49.3%) in the
medical-therapy group died from cardiovascular causes (hazard ratio, 0.79; 95% CI,
0.66 to 0.93; P=0.006 by log-rank test). Death from any cause or hospitalization for
cardiovascular causes occurred in 467 patients (76.6%) in the CABG group and in 524
patients (87.0%) in the medical-therapy group (hazard ratio, 0.72; 95% CI, 0.64 to 0.82;
P<0.001 by log-rank test).
CONCLUSIONS
In a cohort of patients with ischemic cardiomyopathy, the rates of death from any
cause, death from cardiovascular causes, and death from any cause or hospitalization
for cardiovascular causes were significantly lower over 10 years among patients who
underwent CABG in addition to receiving medical therapy than among those who received
medical therapy alone. (Funded by the National Institutes of Health; STICH [and
STICHES] ClinicalTrials.gov number, NCT00023595.
Nanocomposite MFI-alumina and FAU-alumina Membranes: Synthesis, Characterization and Application to Paraffin Separation and CO2 Capture
Rouleau, L. Pirngruber, G. Guillou, F. Barrere-Tricca, C. Omegna, A. Valtchev, V. Pera-Titus, M. Miachon, S. Dalmon, J. A.International audienceIn this work, we report the preparation of thermally and mechanically resistant high-surface (24-cm2) nanocomposite MFI-alumina and FAUalumina membranes by pore-plugging synthesis inside the macropores of α-alumina multilayered tubular supports. The MFI membranes were prepared from a clear solution precursor mixture being able to easily penetrate into the pores of the support. The MFI membranes were evaluated in the separation of n-/i-butane mixtures. The synthesis reliability was improved by mild stirring. The most selective MFI membranes were obtained for supports with mean pore sizes of 0.2 and 0.8 μm. The MFI effective thickness could be reduced to less than 10 μm by impregnating the support with water prior to synthesis and by diluting the synthesis mixture. The best MFI membrane offered an excellent tradeoff between selectivity and permeance at 448 K, with separation factors for equimolar n-butane/i-butane mixtures up to 18 and n-butane mixture permeances as high as 0.7 μmols-1m-2Pa-1.Furthermore, a novel nanocomposite FAU membrane architecture has been obtained by an original synthesis route including in situ seeding using a cold gel-like precursor mixture, followed by growth of the FAU material by hydrothermal synthesis in two steps using a clear solution of low viscosity. This new membrane showed interesting performance in the separation of an equimolar CO2/N2 mixture at 323 K, with CO2/N2 separation factors and mixture CO2 permeances up to 12 and 0.4 μmols-1m-2Pa-1,respectively
Sudden cardiac death in patients with ischemic heart failure undergoing coronary artery bypass grafting results from the STICH randomized clinical trial (Surgical Treatment for Ischemic Heart Failure)
Background—The risk of sudden cardiac death (SCD) in patients with heart failure following CABG has not been examined in a contemporary clinical trial of surgical revascularization. This analysis describes the incidence, timing and clinical predictors of SCD after CABG.
Methods—Patients enrolled in the Surgical Treatment of Ischemic Heart Failure (STICH) trial who underwent CABG with or without surgical ventricular reconstruction (SVR) were included. We excluded patients with prior ICD and those randomized only to medical therapy. The primary outcome was SCD as adjudicated by a blinded committee. A Cox model was used to examine and identify predictors of SCD. The Fine and Gray method was used to estimate the incidence of SCD accounting for the competing risk of other deaths.
Results—Over a median follow-up of 46 months, 113 patients of 1411 patients who received CABG without (n = 934) or with SVR (n = 477) had SCD; 311 died of other causes. The mean LVEF at enrollment was 28±9%. The 5-year cumulative incidence of SCD was 8.5%. Patients who had SCD and those who did not die were younger and had fewer comorbid conditions than those who died for reasons other than SCD. In the first 30 days after CABG, SCD (n=5) accounted for 7% of all deaths. The numerically greatest monthly rate of SCD was in the 31-90 day time period. In a multivariable analysis including baseline demographics, risk factors, coronary anatomy and LV function, ESVI and BNP were most strongly associated with SCD.
Conclusions—The monthly risk of SCD shortly after CABG among patients with a low LVEF is highest between the first and third month, suggesting that risk stratification for SCD should occur early in the postoperative period, particularly in patients with increased preoperative ESVI and/or BNP
The extinction law in high redshift galaxies
We estimate the dust extinction laws in two intermediate redshift galaxies.
The dust in the lens galaxy of LBQS1009-0252, which has an estimated lens
redshift of zl~0.88, appears to be similar to that of the SMC with no
significant feature at 2175 A. Only if the lens galaxy is at a redshift of
zl~0.3, completely inconsistent with the galaxy colors, luminosity or location
on the fundamental plane, can the data be fit with a normal Galactic extinction
curve. The dust in the zl=0.68 lens galaxy for B0218+357, whose reddened image
lies behind a molecular cloud, requires a very flat ultraviolet extinction
curve with (formally) R(V)=12 +- 2. Both lens systems seem to have unusual
extinction curves by Galactic standards.Comment: 15 pages, 3 figures. ApJ in pres
Comparative analysis of anti-polyglutamine Fab crystals grown on Earth and in microgravity
Huntington's disease is one of nine neurodegenerative diseases caused by a polyglutamine (polyQ)-repeat expansion. An anti-polyQ antigen-binding fragment, MW1 Fab, was crystallized both on Earth and on the International Space Station, a microgravity environment where convection is limited. Once the crystals returned to Earth, the number, size and morphology of all crystals were recorded, and X-ray data were collected from representative crystals. The results generally agreed with previous microgravity crystallization studies. On average, microgravity-grown crystals were 20% larger than control crystals grown on Earth, and microgravity-grown crystals had a slightly improved mosaicity (decreased by 0.03°) and diffraction resolution (decreased by 0.2 Å) compared with control crystals grown on Earth. However, the highest resolution and lowest mosaicity crystals were formed on Earth, and the highest-quality crystal overall was formed on Earth after return from microgravity
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