3,768 research outputs found
Effect of Contrast-Enhanced Echocardiograms on the Prognosis of Infective Endocarditis
Objective - Infective endocarditis (IE) is an infectious disease of the cardiac valves where bacteria colonize the valves; typically, via the formation of vegetations. Recent research has shown that the microbubbles in a contrast-enhanced ultrasound (CEUS) examination can move and dislodge bacterial vegetations in vitro. This study investigated whether CEUS resulted in faster resolution of IE in vivo by dislodging the vegetations.
Methods - This IRB approved retrospective study reviewed 36 patients who were diagnosed with IE via echocardiography. Data was sourced from patients within the Jefferson University Hospital’s Cardiology EMR system by searching for contrast and vegetation from January 1st, 2013 – January 1st, 2018. Fifteen patients were not given contrast, whereas 21 patients were given contrast via agitated saline (n=16) or an ultrasound contrast agent (n=5). All patients received an echocardiogram after blood cultures confirmed an infection, but before resolution of infection (defined by negative blood cultures). A student’s t-test was used for analyses.
Results - The study population was heterogeneous in terms of sex (67.5% male) and race (70% Caucasian, 25% African American, and 5% Asian), with an average age of 51±20 years, and an average BMI of 29.65±7.43 in the contrast group and 27.67±3.16 in the non-contrast group (p=0.37). Following ultrasound, no patients had documented stroke, pulmonary embolism, or systemic blood clot, which physicians could have attributed to a thrombus resulting from dislodging of bacterial vegetation. Overall, blood cultures did not clear faster in patients receiving CEUS compared to those undergoing standard echocardiography, (2.63±2.69 days vs. 1.34 ±1.11 days, p=0.09). CEUS also did not shorten the admission length in patients with IE, (16.9±7.7 days vs. 19.9±12.1 days; p=0.36).
Conclusion - Based on this limited sample size, patients who underwent CEUS did not have a different prognosis when compared to patients who received a non-contrast echocardiogram
Comparison of remove-compute-restore and least squares modification of Stokes' formula techniques to quasi-geoid determination over the Auvergne test area
A Comparison of Techniques for the Integration of Satellite Altimeter and Surface Gravity Data for Geoid Determination
Two methods are tested whereby satellite altimeter measurements of the geoid height are combined with surface measurements of the free-air gravity anomaly. The study area comprises the oceans around the Australian continent. The first method involves draping a grid of the free-air anomaly from satellite data onto a grid of the ship and land data. The second method utilises grids of the altimeter-derived geoid height, combining these with the surface data in an iterative superposition. Preliminary results show that the draping method yields a fit of 5.4 mGal between the satellite and marine data, while the iterative procedure returns 8.1 mGal. Further work can be done, however, to improve these results. The impact of the combined marine gravity data sets is illustrated by comparing the effects on an Australia-wide spherical-FFT geoid solution
New approaches for estimating risk from exposure to diethylstilbestrol.
A subgroup from a National Institute of Environmental Health Sciences, workshop concerned with characterizing the effects of endocrine disruptors on human health at environmental exposure levels considered the question, If diethylstilbestrol (DES) were introduced into the market for human use today and likely to result in low-dose exposure of the human fetus, what would be required to assess risk? On the basis of an analysis of the quality of data on human DES exposure, the critical times and doses for inducing genital tract malformations and cancer must be determined. This would be facilitated through analysis of the ontogeny of estrogen receptor expression in the developing human genital tract. Models of low-dose estrogenic effects will have to be developed for human and rodent genital tract development. Mouse models offer many advantages over other potential animal models because of the wealth of the earlier literature, the availability of sensitive end points, the availability of mutant lines, and the possibility of generating genetically engineered model systems. Through multidisciplinary approaches, it should be possible to elucidate the cellular and molecular mechanisms of endocrine disruption elicited by estrogens during development and facilitate an assessment of risk to humans
Diffusion of particles in an expanding sphere with an absorbing boundary
We study the problem of particles undergoing Brownian motion in an expanding
sphere whose surface is an absorbing boundary for the particles. The problem is
akin to that of the diffusion of impurities in a grain of polycrystalline
material undergoing grain growth. We solve the time dependent diffusion
equation for particles in a d-dimensional expanding sphere to obtain the
particle density function (function of space and time). The survival rate or
the total number of particles per unit volume as a function of time is
evaluated. We have obtained particular solutions exactly for the case where d=3
and a parabolic growth of the sphere. Asymptotic solutions for the particle
density when the sphere growth rate is small relative to particle diffusivity
and vice versa are derived.Comment: 12 pages. To appear in J. Phys. A: Math. Theor. 41 (2008
Contrast-enhanced ultrasound identifies early extrahepatic collateral contributing to residual hepatocellular tumor viability after transarterial chemoembolization.
The mainstay of treatment for unresectable hepatocellular carcinoma is locoregional therapy including percutaneous ablation and transarterial chemo- and radioembolization. While monitoring for tumor response after transarterial chemoembolization is crucial, current imaging strategies are suboptimal. The standard of care is contrast-enhanced magnetic resonance imaging or computed tomography imaging performed at least 4 to 6 weeks after therapy. We present a case in which contrast-enhanced ultrasound identified a specific extra-hepatic collateral from the gastroduodenal artery supplying residual viable tumor and assisting with directed transarterial management
Harmonic generation of gravitational wave induced Alfven waves
Here we consider the nonlinear evolution of Alfven waves that have been
excited by gravitational waves from merging binary pulsars. We derive a wave
equation for strongly nonlinear and dispersive Alfven waves. Due to the weak
dispersion of the Alfven waves, significant wave steepening can occur, which in
turn implies strong harmonic generation. We find that the harmonic generation
is saturated due to dispersive effects, and use this to estimate the resulting
spectrum. Finally we discuss the possibility of observing the above process.Comment: 7 page
Motivational Interviewing in an ordinary clinical setting: A controlled clinical trial at the Swedish National Tobacco Quitline
AbstractIntroductionThe present study aimed to assess the effect of adding Motivational Interviewing (MI) to the first session of an effective smoking cessation treatment protocol in an ordinary clinical setting: the Swedish National Tobacco Quitline (SNTQ).MethodThe study was designed as a controlled clinical trial. Between September 2005 and October 2006, 772 clients accepted the invitation to participate in the study and were semi-randomised to either standard treatment (ST) or MI. The primary outcome measures were self-reported 7-day point prevalence abstinence and 6-month continuous abstinence.ResultsAt 12-month follow-up, the 772 clients were included in an intention to treat analysis. Of the clients allocated to MI, 57/296 (19%) reported 6-month continuous abstinence compared to 66/476 (14%) of the clients allocated to ST (OR 1.48, 95% CI 1.00–2.19; P=.047).ConclusionsIntegrating MI into a cognitive behavioural therapy-based smoking cessation counselling in an ordinary clinical setting at a tobacco quitline increased client 6-month continuous abstinence rates by 5%
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