University of Vermont

About: University of Vermont is a education organization based out in Burlington, Vermont, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 17592 authors who have published 38251 publications receiving 1609874 citations. The organization is also known as: UVM & University of Vermont and State Agricultural College.

Checking the Independence of Two Covariance-Stationary Time Series: A Univariate Residual Cross-Correlation Approach

Abstract: A two-stage method is proposed for investigating the independence of two covariance-stationary time series. It involves, first, fitting univariate models to each of the series, and then cross-correlating the two residual series thereby obtained. The asymptotic distribution of such a set of lagged residual cross-correlations is established to be of a very simple form under the null hypothesis of the two series' independence. A Monte Carlo study verifies the applicability of this distribution for series of length N = 50, 100, and 200. An attendant chi-square test statistic is discussed.

Myocardial stiffness in patients with heart failure and a preserved ejection fraction contributions of collagen and titin

Abstract: Background—The purpose of this study was to determine whether patients with heart failure and a preserved ejection fraction (HFpEF) have an increase in passive myocardial stiffness and the extent to which discovered changes depend on changes in extracellular matrix fibrillar collagen and cardiomyocyte titin. Methods and Results—Seventy patients undergoing coronary artery bypass grafting underwent an echocardiogram, plasma biomarker determination, and intraoperative left ventricular epicardial anterior wall biopsy. Patients were divided into 3 groups: referent control (n=17, no hypertension or diabetes mellitus), hypertension (HTN) without (–) HFpEF (n=31), and HTN with (+) HFpEF (n=22). One or more of the following studies were performed on the biopsies: passive stiffness measurements to determine total, collagen-dependent and titin-dependent stiffness (differential extraction assay), collagen assays (biochemistry or histology), or titin isoform and phosphorylation assays. In comparison with controls, pat...

Sleep duration and biomarkers of inflammation.

Abstract: MOUNTING EVIDENCE FROM BOTH OBSERVATIONAL AND EXPERIMENTAL RESEARCH SUGGESTS SLEEP DURATION PLAYS AN IMPORTANT ROLE IN HEALTH. Studies suggest both short and extended durations of sleep are associated with increased risk for all-cause mortality, coronary heart disease, diabetes, and obesity.1–5 The mechanisms by which altered sleep duration affects health are unclear, but experimental studies suggest altered sleep may impact levels of cytokines known to be important in regulating inflammation. Experimental sleep deprivation has been shown to acutely elevate pro-inflammatory cytokine levels including C-reactive protein (CRP) and interleukin-6 (IL-6).6–8 However, it is not clear whether this pro-inflammatory effect observed with short-term sleep deprivation experiments persists chronically. While one week of modest sleep restriction has been associated with elevations in IL-6 and tumor necrosis factor alpha (TNFα),9 a large population based study found no relationship between habitual sleep duration in the long term and CRP levels.10 Because chronic elevations in cytokines such as CRP and IL-6 are associated with an increased risk of adverse health outcomes such as diabetes and heart disease,11–13 any effect of sleep duration on regulation of these cytokines could have important long-term health effects. In this study, we sought to use a well-characterized cohort with standardized polysomnography (PSG) that allowed careful adjustment for sleep apnea severity, to examine whether an association exists between sleep duration and inflammatory mediators that might explain the associations between sleep duration and disease.