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Although widely used in cardiology, relation of heart failure biomarkers to cardiac haemodynamics in patients with CHD (and in particular with pulmonary insufficiency undergoing pulmonary valve replacement) remains unclear. We hypothesised that the cardiac function biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity 2, and galectin-3 would have significant associations to right ventricular haemodynamic derangements.
Consecutive patients ( n = 16) undergoing cardiac catheterisation for transcatheter pulmonary valve replacement were studied. NT-proBNP, soluble suppressor of tumorigenicity 2, and galectin-3 levels were measured using a multiplex enzyme-linked immunosorbent assay from a pre-intervention blood sample obtained after sheath placement. Spearman correlation was used to identify significant correlations (p ≤ 0.05) of biomarkers with baseline cardiac haemodynamics. Cardiac MRI data (indexed right ventricular and left ventricular end-diastolic volumes and ejection fraction) prior to device placement were also compared to biomarker levels.
NT-proBNP and soluble suppressor of tumorigenicity 2 were significantly correlated (p < 0.01) with baseline mean right atrial pressure and right ventricular end-diastolic pressure. Only NT-proBNP was significantly correlated with age. Galectin-3 did not have significant associations in this cohort. Cardiac MRI measures of right ventricular function and volume were not correlated to biomarker levels or right heart haemodynamics.
NT-proBNP and soluble suppressor of tumorigenicity 2, biomarkers of myocardial strain, significantly correlated to invasive pressure haemodynamics in transcatheter pulmonary valve replacement patients. Serial determination of soluble suppressor of tumorigenicity 2, as it was not associated with age, may be superior to serial measurement of NT-proBNP as an indicator for timing of pulmonary valve replacement.
In the United States alone, ∼14,000 children are hospitalised annually with acute heart failure. The science and art of caring for these patients continues to evolve. The International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was held on February 4 and 5, 2015. The 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was funded through the Andrews/Daicoff Cardiovascular Program Endowment, a philanthropic collaboration between All Children’s Hospital and the Morsani College of Medicine at the University of South Florida (USF). Sponsored by All Children’s Hospital Andrews/Daicoff Cardiovascular Program, the International Pediatric Heart Failure Summit assembled leaders in clinical and scientific disciplines related to paediatric heart failure and created a multi-disciplinary “think-tank”. The purpose of this manuscript is to summarise the lessons from the 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute, to describe the “state of the art” of the treatment of paediatric cardiac failure, and to discuss future directions for research in the domain of paediatric cardiac failure.
The diary of John Rous (1584–1644) was edited for the Camden Society in 1856 by Mary Anne Everett Green (1818–95). Rous kept this diary between 1625 and 1643, when he was vicar of Santon Downham in Suffolk, recording both local events and reports of momentous happenings in Britain and abroad from Charles I's accession to the outbreak of the Civil War. M. A. E. Green was educated by her father, a Methodist minister, and began research on historical topics in the British Museum Reading Room and other London archives. She was recommended to Sir John Romilly as an external editor for the Calendar of State Papers project, and was the first to be appointed: her work became the standard which later editors followed. Rous's diary is preceded by an introduction placing its author in his family and historical context, and Green's notes explicate references to the people and events described.
Mass ejection in the form of winds or jets appears to be as fundamental to quasar activity as accretion. A convincing argument for radiation pressure driving this ionized outflow can be made within the dust sublimation radius. Beyond, radiation pressure is even more ubiquitous, as high energy photons from the central engine can now push on dust grains. This physics underlies the dusty-wind model for the putative obscuring torus. Specifically, the dusty wind in our model is first launched from the outer accretion disk as a magneto-centrifugal wind and then accelerated and shaped by radiation pressure from the central continuum. Such a wind can plausibly account for both the necessary obscuring medium to explain the observed ratio of broad-to-narrow-line quasars and the mid-infrared emission commonly seen in quasar spectral energy distributions.
Despite the absence of artificial light pollution at Antarctic plateau sites such as Dome A, other factors such as airglow, aurorae and extended periods of twilight have the potential to adversely affect optical observations. We present a statistical analysis of the airglow and aurorae at Dome A using spectroscopic data from Nigel, an optical/near-IR spectrometer operating in the 300–850 nm range. The median auroral contribution to the B, V and R photometric bands is found to be 22.9, 23.4 and 23.0 mag arcsec−2 respectively. We are also able to quantify the amount of annual dark time available as a function of wavelength; on average twilight ends when the Sun reaches a zenith distance of 102.6°.
Starting from first principles, we construct a simple model for the evolution of energetic particles produced by supernovae in the starburst galaxy M82. The supernova rate, geometry, and properties of the interstellar medium are all well observed in this nearby galaxy. Assuming a uniform interstellar medium and constant cosmic-ray injection rate, we estimate the cosmic-ray proton and primary & secondary electron/positron populations. From these particle spectra, we predict the gamma ray flux and the radio synchrotron spectrum. The model is then compared to the observed radio and gamma-ray spectra of M82 as well as previous models by Torres (2004), Persic et al. (2008), and de Cea del Pozo et al. (2009). Through this project, we aim to build a better understanding of the calorimeter model, in which energetic particle fluxes reflect supernova rates, and a better understanding of the radio-FIR correlation in galaxies.
The low masses of irregular galaxies change the behavior of their interstellar medium (ISM) compared to that of normal spirals, so the role of magnetic fields in the ISM in irregulars may be very different than in spirals. We present high-resolution and high-sensitivity observations of the magnetic fields of two irregular galaxies: NGC 4214 and NGC 1569.
We present the results of eighteen non-continuous nights of time series photometric observations of a 1.25 deg2 field in Cygnus centered on the NASA Kepler Mission field of view. Using the Case Western Burrell Schmidt telescope we gathered a dataset containing light curves of roughly 30,000 stars with 14 < r < 19. We have statistically examined each light curve to test for variability, periodicity, and unusual light curve trends, including exoplanet transits. We present a summary of our photometric project including a characterization of the level and content of stellar variability in this field. We will also discuss our potential exoplanet candidates.
Studies of tetraploid[harr ]diploid (4n[harr ]2n) mouse chimaeras have demonstrated unequal contributions of 4n
cells to different tissues of the midgestation conceptus. Such a pattern has also been reported in chimaeras as
early as E3.5d, which show an enhanced contribution of 4n cells to the mural trophectoderm (Everett &
West, 1996). In this study, sectioned 4n[harr ]2n and 2n[harr ]2n control chimaeric blastocysts were digitised and
reconstructed in 3 dimensions (3-D). The 3-D images revealed only limited mixing of cells from the 2
contributing embryos of individual blastocysts in both chimaera groups. Consequently, the distribution
pattern of the 2 cell types was dependent on the spatial relationship between the orientation of the
blastocyst and the boundary between the 2 clusters of cells. The distribution patterns observed were not
strikingly different for 4n[harr ]2n and 2n[harr ]2n chimaeras, each showing some transgenic positive cell
contribution in all 3 identifiable developmental lineages. It was notable, however, that in all 4n[harr ]2n
blastocysts at least some 4n cells were located adjacent to the blastocyst cavity. Such a consistent pattern
was not evident in 2n[harr ]2n chimaeras. This study has demonstrated the value of 3-D reconstructions for the
analysis of spatial relationships of 2 cell populations in chimaeric mouse blastocysts.
Tetraploid (4n) cells do not contribute equally to all tissues
of midgestation mouse chimaeras and
mosaics. Our previous studies of early blastocysts showed that 4n cells
are preferentially allocated
to the mural trophectoderm of the early blastocyst and this may contribute
to the restricted
distribution pattern seen at later stages. In this study of later-stage
blastocysts we found evidence
for selection against 4n cells. The contribution of 4n cells to 4n[harr ]2n
decreased between E3·5 and E4·5 days, whereas the composition
of 2n[harr ]2n controls changed little
over this period. These results suggest that, prior to implantation, blastocysts
have already lost
some tetraploid cells from their embryonic and extra-embryonic lineages
due to a combination of
preferential allocation of 4n cells to the mural trophectoderm and selection
against 4n cells
throughout the embryo.