A5087419243- Advanced MRI Techniques and Applications
- Cardiac electrophysiology and arrhythmias
- Frailty in Older Adults
- Cardiomyopathy and Myosin Studies
- Cardiovascular Function and Risk Factors
- Nutrition and Health in Aging
- Cardiac Imaging and Diagnostics
- Ion channel regulation and function
- Neuroscience and Neuropharmacology Research
- Heart Failure Treatment and Management
- Optical Imaging and Spectroscopy Techniques
- Viral Infections and Immunology Research
- Cardiac Fibrosis and Remodeling
- Mitochondrial Function and Pathology
- Cardiovascular Effects of Exercise
- Cardiac pacing and defibrillation studies
- GDF15 and Related Biomarkers
- Receptor Mechanisms and Signaling
- Cardiac Ischemia and Reperfusion
- Muscle Physiology and Disorders
- Mechanics and Biomechanics Studies
- Opioid Use Disorder Treatment
- Pharmacology and Obesity Treatment
- Traumatic Brain Injury and Neurovascular Disturbances
- Substance Abuse Treatment and Outcomes
Oregon Health & Science University
2015-2024
Barro Colorado Island
2024
National Center for Advancing Translational Sciences
2024
National Institute of Nursing Research
2024
University of Central Florida
2018
San Francisco General Hospital
1994-1999
University of California, San Francisco
1989-1999
Loyola University Chicago
1994
United States Department of Veterans Affairs
1989
<h3>Importance</h3> The use of sacubitril/valsartan is not endorsed by practice guidelines for in patients with New York Heart Association class IV heart failure a reduced ejection fraction because limited clinical experience this population. <h3>Objective</h3> To compare treatment valsartan advanced and recent symptoms. <h3>Design, Setting, Participants</h3> A double-blind randomized trial was conducted; total 335 were included. began on March 2, 2017, stopped early 23, 2020, owing to...
Background: Although women with heart failure (HF) are potentially more likely to be physically frail compared men HF, the underlying contributors this sex difference poorly understood. The purpose of study was characterize differences in physical frailty phenotypes HF. Methods: We prospectively enrolled adults class I–IV Physical measured phenotype criteria. Symptoms dyspnea, sleep-related impairment, pain interference, depression, and anxiety were assessed. Body composition using...
Sarcomere relaxation depends on dissociation of actin and myosin, which is regulated by a number factors, including intracellular [MgATP] as well MgATP hydrolysis products [MgADP] inorganic phosphate [Pi], pHi, cytosolic calcium concentration ([Ca2+]c). To distinguish the contribution MgADP from other regulators in development diastolic dysfunction, we used strategy to increase free without changing [MgATP], or pHi. This was achieved applying low dose iodoacetamide selectively inhibit...
We asked whether thyroid hormone (T4) would improve heart function in left ventricular hypertrophy (LVH) induced by pressure overload (aortic banding). After banding for 10-22 wk, rats were treated with T4 or saline 10-14 d. Isovolumic LV and cytosolic [Ca2+] (indo-1) assessed perfused hearts. Sarcoplasmic reticulum Ca2+-ATPase (SERCA), phospholamban, alpha- beta-myosin heavy chain (MHC) proteins assayed homogenates of myocytes isolated from the same Of 14 banded hearts saline, 8 had...
The changes in myocardial high energy phosphates and pH during regional ischemia, their potential role mediating functional abnormalities, is unclear. To determine the degree of blood flow reduction required to induce pH, correlate these metabolic with alterations flow, 31P nuclear magnetic resonance spectroscopy was employed an vivo porcine model graded coronary stenosis. Simultaneous measurements phosphate compounds were made various steady-state degrees ischemia which subendocardial...
The mechanisms responsible for changes in myocardial contractility during regional ischemia are unknown. Since high-energy phosphates sensitive to reductions blood flow, it was hypothesized that function under steady-state conditions of graded is closely related phosphates. Therefore, phosphorus-31 nuclear magnetic resonance spectroscopy employed an vivo porcine model coronary stenosis. Simultaneous measurements subendocardial phosphates, pH, and segment shortening were made various degrees...
The free energy release from ATP hydrolysis (|DeltaG approximately p|) is decreased by inhibiting the creatine kinase (CK) reaction, which may limit thermodynamic driving force for sarcoplasmic reticulum (SR) Ca2+ pumps and thereby cause a decrease in contractile reserve. To determine whether |DeltaG p| results reserve impairing handling, we measured left ventricular pressure cytosolic Ca2+concentration ([Ca2+]c; indo 1 fluorescence) isolated perfused rat hearts, with >95% inhibition of CK...
Fluorescence spectroscopy of beating hearts has been used previously to measure intracellular regulators function. Unfortunately, heart motion could introduce a spurious artifact (MA), influencing the measured fluorescence intensity (“signal”). To suppress MA, ratio (or difference) calculated between signal and an reference detected at different wavelength (“reference”). However, no studies have attempted evaluate or optimize efficiency MA suppression. suppression was evaluated using...
Transmural heterogeneity of myocardial metabolism and function are present in the left ventricle under normal ischemic conditions. To determine if endocardial versus epicardial differences [Ca2+]i also present, perfused rat heart studies using indo-1 fluorescence as an index were performed ventricular epicardium endocardium. Hearts studied during control conditions low-flow ischemia. Results demonstrated following: 1) At a pacing rate 1.5 Hz, levels diastolic systolic (470 +/- 40 1,240 170...
Abstract Aims Physical frailty is highly prevalent and predictive of worse outcomes in heart failure (HF). Candidate biomarker analysis may help understanding the mechanisms underlying physical HF. We aimed to identify candidate biomarkers associated with HF using a multimarker strategy distinct pathophysiological processes. Methods results collected data plasma samples from 113 adults New York Heart Association Functional Class I–IV was measured Frailty Phenotype Criteria. Plasma included:...
To determine the effect of isoproterenol on cardiac energetics and function in an animal preparation cardiomyopathy, we studied Langendorff perfused hearts from Syrian cardiomyopathic hamsters. High-energy phosphate metabolites (phosphocreatine [PCr], ATP, inorganic [Pi]) intracellular pH (pHi) were measured by 31P nuclear magnetic resonance spectroscopy correlated with left ventricular developed pressure, coronary flow, O2 consumption before during a 10(-6)M infusion isoproterenol. Total...
The mechanisms that impair myocardial relaxation during ischemia are believed to involve abnormalities of calcium handling. However, there is little direct evidence support this hypothesis. Therefore, we sought determine whether the time constant cytosolic ([Ca2+]c) decline (tau Ca) was increased low flow ischemia, and if a relationship between left ventricular pressure P) tau Ca. Isolated perfused hearts were studied using indo-1 fluorescence ratio as an index [Ca2+]c.tau P used relaxation....
Both cytosolic free Ca2+ ([Ca2+]i) decline and myocardial relaxation are slowed in severe hypertrophy heart failure. However, it is not certain whether this occurs mild to moderate hypertrophy. Therefore, we tested the hypotheses that slowing of [Ca2+]i 1) hypertrophy, 2) absence relaxation, 3) related degree Experiments were performed on isolated rat hearts subjected pressure overload. Indo 1 fluorescence was used as an index [Ca2+]i. assessed by time constant exponential (tau Ca) left...
Coronary artery stenosis or occlusion results in reduced coronary flow and myocardial contractile depression. At severe reductions, increased inorganic phosphate (Pi) intracellular acidosis clearly play a role However, during milder reductions the mechanism(s) underlying depression are less clear. Previous perfused heart studies demonstrated no change of Pi pH mild suggesting that changes intravascular pressure (garden hose effect) may be mediator this Others have reported conflicting...
The goal of this study was to determine whether Ca 2+ plays a role in regulating tension development kinetics intact cardiac muscle. In muscle, fundamental issue regulation has been controversial. approach induce steady-state tetanic contractions right ventricular trabeculae from rat hearts at varying external concentrations ([Ca ]) 22°C. During tetani, cross bridges were mechanically disrupted and the redevelopment assessed rate constant exponential ( k tr ). There relationship between [Ca...