To establish a classification of bicuspid aortic valve (BAV) that includes both leaflet morphology and aortic shape.
Two academic medical centres of the University of Washington, Seattle.
191 adult ...patients with BAV.
Review of clinical data and transthoracic echocardiograms.
Assessment of leaflet morphology; valve function; aortic shape and dimensions.
We identified three morphologies: type 1, fusion of right and left coronary cusp (n = 152); type 2, right and non-coronary fusion (n = 39); and type 3, left and non-coronary fusion (n = 1). Comparing type 1 and 2 BAV, there were no significant differences in age, height, weight, blood pressure or aortic valve function. Type 1 was more common in men (69 vs 45%). The aortic sinuses were larger in type 1, while type 2 had larger arch dimensions. Myxomatous mitral valves were more common in type 2 BAV (13% vs 2.6%, p<0.05). Three aortic shapes were defined: normal (N), sinus effacement (E), and ascending dilatation (A). Comparing type 1 to type 2 BAV, shape N was more common in type 1 (60% vs 32%), and type A was more common in type 2 (35% vs 54%,); type E was rare (p<0.01 across all groups).
A comprehensive BAV phenotype includes aortic shape. Type 1 BAV is associated with male gender and normal aortic shape but a larger sinus diameter. Type 2 leaflet morphology is associated with ascending aorta dilatation , larger arch dimensions and higher prevalence of myxomatous mitral valve disease.
Abstract Purpose To evaluate the diagnostic performance of ultrasound elastography in breast masses. Material and methods 193 lesions (129 benign, 64 malignant) were analyzed with the EUB 8500 ...Logos-ultrasonic-unit (Hitachi Medical, Japan) and a linear-array-transducer of 7.5–13-MHz. Standard of reference was cytology (FNAfine needle aspiration) or histology (core biopsy). The elastic-score was classified according to a 6-point colour-scale (Ueno classification; 1–3 = benign, 4–5 = malignant). Conventional B-mode ultrasound (US) findings were classified according to the BI-RADS classification. Statistical analysis included sensitivity, specificity, ROC-analysis and kappa-values for intra-/interobserver reliability. Results The mean score for elasticity was 4.1 ± 0.9 for malignant lesions, and 2.1 ± 1.0 for benign lesions ( p < 0.001). With a best cut-off point between elasticity scores 3 and 4, sensitivity was 96.9%, and specificity 76%. Setting a best cut-off point for conventional US between BI-RADS 4 and 5, sensitivity was 57.8%, and specificity 96.1%. Elastography provided higher sensitivity and lower specificity than conventional US, but two lesions with elasticity score 1 were false negative, whereas no lesion scored BI-RADS 1–3 were false negative. ROC-curve was 0.884 for elastography, and 0.820 for conventional US ( p < 0.001). Weighted kappa-values for intra-/interobserver reliability were 0.784/0.634 for BI-RADS classification, and 0.720/0.561 for elasticity scores. Conclusion In our study setting, elastography does not have the potential to replace conventional B-mode US for the detection of breast cancer, but may complement conventional US to improve the diagnostic performance.
The rapid emergence of the COVID-19 pandemic is unprecedented and poses an unparalleled obstacle in the sixty-five year history of organ transplantation. Worldwide, the delivery of transplant care is ...severely challenged by matters concerning - but not limited to - organ procurement, risk of SARS-CoV-2 transmission, screening strategies of donors and recipients, decisions to postpone or proceed with transplantation, the attributable risk of immunosuppression for COVID-19 and entrenched health care resources and capacity. The transplant community is faced with choosing a lesser of two evils: initiating immunosuppression and potentially accepting detrimental outcome when transplant recipients develop COVID-19 versus postponing transplantation and accepting associated waitlist mortality. Notably, prioritization of health care services for COVID-19 care raises concerns about allocation of resources to deliver care for transplant patients who might otherwise have excellent 1-year and 10-year survival rates. Children and young adults with end-stage organ disease in particular seem more disadvantaged by withholding transplantation because of capacity issues than from medical consequences of SARS-CoV-2. This report details the nationwide response of the Dutch transplant community to these issues and the immediate consequences for transplant activity. Worrisome, there was a significant decrease in organ donation numbers affecting all organ transplant services. In addition, there was a detrimental effect on transplantation numbers in children with end-organ failure. Ongoing efforts focus on mitigation of not only primary but also secondary harm of the pandemic and to find right definitions and momentum to restore the transplant programs.
Planck 2015 results Ade, P A R; Aghanim, N; Arnaud, M ...
Astronomy and astrophysics (Berlin),
10/2016, Letnik:
594
Journal Article
Recenzirano
Odprti dostop
We study the implications of Planck data for models of dark energy (DE) and modified gravity (MG) beyond the standard cosmological constant scenario. We start with cases where the DE only directly ...affects the background evolution, considering Taylor expansions of the equation of state w(a), as well as principal component analysis and parameterizations related to the potential of a minimally coupled DE scalar field. When estimating the density of DE at early times, we significantly improve present constraints and find that it has to be below ~2% (at 95% confidence) of the critical density, even when forced to play a role for z< 50 only. We then move to general parameterizations of the DE or MG perturbations that encompass both effective field theories and the phenomenology of gravitational potentials in MG models. Lastly, we test a range of specific models, such as k-essence, f(R) theories, and coupled DE. In addition to the latest Planck data, for our main analyses, we use background constraints from baryonic acoustic oscillations, type-Ia supernovae, and local measurements of the Hubble constant. We further show the impact of measurements of the cosmological perturbations, such as redshift-space distortions and weak gravitational lensing. These additional probes are important tools for testing MG models and for breaking degeneracies that are still present in the combination of Planck and background data sets. All results that include only background parameterizations (expansion of the equation of state, early DE, general potentials in minimally-coupled scalar fields or principal component analysis) are in agreement with LambdaCDM. When testing models that also change perturbations (even when the background is fixed to LambdaCDM), some tensions appear in a few scenarios: the maximum one found is ~2sigma for Planck TT+lowP when parameterizing observables related to the gravitational potentials with a chosen time dependence; the tension increases to, at most, 3sigma when external data sets are included. It however disappears when including CMB lensing.
Malignant pleural mesothelioma is a disease primarily associated with exposure to the carcinogen asbestos. Whereas other carcinogen-related tumors are associated with a high tumor mutation burden, ...mesothelioma is not. We sought to resolve this discrepancy.
We used mate-pair (n = 22), RNA (n = 28), and T cell receptor sequencing along with in silico predictions and immunologic assays to understand how structural variants of chromosomes affect the transcriptome.
We observed that inter- or intrachromosomal rearrangements were present in every specimen and were frequently in a pattern of chromoanagenesis such as chromoplexy or chromothripsis. Transcription of rearrangement-related junctions was predicted to result in many potential neoantigens, some of which were proven to bind patient-specific major histocompatibility complex molecules and to expand intratumoral T cell clones. T cells responsive to these predicted neoantigens were also present in a patient’s circulating T cell repertoire. Analysis of genomic array data from the mesothelioma cohort in The Cancer Genome Atlas suggested that multiple chromothriptic-like events negatively impact survival.
Our findings represent the discovery of potential neoantigen expression driven by structural chromosomal rearrangements. These results may have implications for the development of novel immunotherapeutic strategies and the selection of patients to receive immunotherapies.
Various CTP parameters have been used to identify ischemic penumbra. The purpose of this study was to determine the optimal CTP parameter and threshold to distinguish true "at-risk" penumbra from ...benign oligemia in acute stroke patients without reperfusion.
Consecutive stroke patients were screened and 23 met the following criteria: 1) admission scanning within 9 hours of onset, 2) CTA confirmation of large vessel occlusion, 3) no late clinical or radiographic evidence of reperfusion, 4) no thrombolytic therapy, 5) DWI imaging within 3 hours of CTP, and 6) either CT or MR follow-up imaging. CTP was postprocessed with commercial software packages, using standard and delay-corrected deconvolution algorithms. Relative cerebral blood flow, volume, and mean transit time (rCBF, rCBV and rMTT) values were obtained by normalization to the uninvolved hemisphere. The admission DWI and final infarct were transposed onto the CTP maps and receiver operating characteristic curve analysis was performed to determine optimal thresholds for each perfusion parameter in defining penumbra destined to infarct.
Relative and absolute MTT identified penumbra destined to infarct more accurately than CBF or CBV*CBF (P < .01). Absolute and relative MTT thresholds for defining penumbra were 12s and 249% for the standard and 13.5s and 150% for the delay-corrected algorithms, respectively.
Appropriately thresholded absolute and relative MTT-CTP maps optimally distinguish "at-risk" penumbra from benign oligemia in acute stroke patients with large-vessel occlusion and no reperfusion. The precise threshold values may vary, however, depending on the postprocessing technique used for CTP map construction.
Abstract
The most powerful tests of stellar models come from the brightest stars in the sky, for which complementary techniques, such as astrometry, asteroseismology, spectroscopy and interferometry, ...can be combined. The K2 mission is providing a unique opportunity to obtain high-precision photometric time series for bright stars along the ecliptic. However, bright targets require a large number of pixels to capture the entirety of the stellar flux, and CCD saturation, as well as restrictions on data storage and bandwidth, limit the number and brightness of stars that can be observed. To overcome this, we have developed a new photometric technique, which we call halo photometry, to observe very bright stars using a limited number of pixels. Halo photometry is simple, fast and does not require extensive pixel allocation, and will allow us to use K2 and other photometric missions, such as TESS, to observe very bright stars for asteroseismology and to search for transiting exoplanets. We apply this method to the seven brightest stars in the Pleiades open cluster. Each star exhibits variability; six of the stars show what are most likely slowly pulsating B-star pulsations, with amplitudes ranging from 20 to 2000 ppm. For the star Maia, we demonstrate the utility of combining K2 photometry with spectroscopy and interferometry to show that it is not a ‘Maia variable’, and to establish that its variability is caused by rotational modulation of a large chemical spot on a 10 d time-scale.
We use data from the Sydney-AAO Multi-Object Integral Field Spectrograph Galaxy Survey and the Galaxy And Mass Assembly (GAMA) survey to investigate the spatially resolved signatures of the ...environmental quenching of star formation in galaxies. Using dust-corrected measurements of the distribution of H... emission, we measure the radial profiles of star formation in a sample of 201 star-forming galaxies covering three orders of magnitude in stellar mass (M*; 10 super( 8.1)-10 super( 10.95) M...) and in fifth nearest neighbour local environment density (...; 10 super( -1.3)-10 super( 2.1) Mpc super( -2)). We show that star formation rate gradients in galaxies are steeper in dense (log sub( 10)(.../Mpc super( 2)) > 0.5) environments by 0.58 plus or minus 0.29dexr sub( e) super( -1) in galaxies with stellar masses in the range 10 super( 10)<M*/M...<10 super( 11) and that this steepening is accompanied by a reduction in the integrated star formation rate. However, for any given stellar mass or environment density, the star formation morphology of galaxies shows large scatter. We also measure the degree to which the star formation is centrally concentrated using the unitless scale-radius ratio (r sub( 50,H...)/r sub( 50,cont)), which compares the extent of ongoing star formation to previous star formation. With this metric, we find that the fraction of galaxies with centrally concentrated star formation increases with environment density, from ~5 plus or minus 4 per cent in low-density environments (log sub( 10)(.../Mpc super( 2)) < 0.0) to 30 plus or minus 15 per cent in the highest density environments (log sub( 10)(.../Mpc super( 2)) > 1.0). These lines of evidence strongly suggest that with increasing local environment density, the star formation in galaxies is suppressed, and that this starts in their outskirts such that quenching occurs in an outside-in fashion in dense environments and is not instantaneous. (ProQuest: ... denotes formulae/symbols omitted.)
Cosmic shear is one of the primary probes to test gravity with current and future surveys. There are two main techniques to analyse a cosmic shear survey: a tomographic method, where correlations ...between the lensing signals in different redshift bins are used to recover redshift information, and a 3D approach, where the full redshift information is carried through the entire analysis. Here we compare the two methods, by forecasting cosmological constraints for future surveys like Euclid. We extend the 3D formalism for the first time to theories beyond the standard model, belonging to the Horndeski class. This includes the majority of universally coupled extensions to ΛCDM with one scalar degree of freedom in addition to the metric, still in agreement with current observations. Given a fixed background, the evolution of linear perturbations in Horndeski gravity is described by a set of four functions of time only. We model their time evolution assuming proportionality to the dark energy density fraction and place Fisher matrix constraints on the proportionality coefficients. We find that a 3D analysis can constrain Horndeski theories better than a tomographic one, in particular with a decrease in the errors of the order of 20|${{\ \rm per\ cent}}$|. This paper shows for the first time a quantitative comparison on an equal footing between Fisher matrix forecasts for both a fully 3D and a tomographic analysis of cosmic shear surveys. The increased sensitivity of the 3D formalism comes from its ability to retain information on the source redshifts along the entire analysis.
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