The relative impacts of regional and generalized adiposity on insulin sensitivity have not been fully defined. Therefore, we investigated the relationship (measured using hyperinsulinemic, euglycemic clamp technique with [3-3H]glucose turnover) to total body (determined by hydrodensitometry) adiposity. latter was assessed determining subcutaneous abdominal, intraperitoneal, retroperitoneal fat masses (using magnetic resonance imaging) sum truncal peripheral skinfold thicknesses. 39 healthy...

Background —Tumor necrosis factor-α (TNF-α) is a multifunctional cytokine that has been detected in several human cardiac-related conditions, including congestive heart failure and septic cardiomyopathy. In these the origin of TNF-α secretion is, at least part, cardiac myocytes. Methods Results —To determine consequences production by myocytes vivo, we developed transgenic mice which expression murine coding sequence was driven α-myosin heavy chain promoter. Four founders an identical...

Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically hypertension valvular heart disease). If is treated, LV regresses, suggesting a sensitivity work. However, whether physical inactivity nonathletic populations causes adaptive mass even frank atrophy not clear. We exposed previously sedentary men 6 ( n = 5) and 12 3) wk of horizontal bed rest. right (RV)...

Because determination of neurologic integrity after severe limb trauma is crucial in patient care, the authors assessed magnetic resonance (MR) imaging as a tool to map denervated motor units skeletal muscle patients with traumatic peripheral neuropathy. Denervation was confirmed 22 use electromyography, surgery, or both. MR performed moderately T1- and T2-weighted spin-echo short-tau inversion-recovery (STIR) sequences. unreliable depicting acute denervation. Muscles subacute denervation...

It is unclear whether, and to what extent, the striking cardiac morphological manifestations of endurance athletes are a result exercise training or genetically determined characteristic talented athletes. We hypothesized that prolonged intensive in previously sedentary healthy young individuals could induce remodeling similar observed cross-sectionally elite athletes.Twelve subjects (aged 29±6 years; 7 men 5 women) trained progressively intensively for 12 months such they compete marathon....

Left atrial (LA) structural and functional abnormalities may be subclinical phenotypes, which identify individuals at increased risk of adverse outcomes. Maximum LA volume (LAmax) emptying fraction (LAEF) were measured via cardiac magnetic resonance imaging in 1802 participants the Dallas Heart Study. The associations LAEF LAmax indexed to body surface area (LAmax/BSA) with traditional factors, natriuretic peptide levels, left ventricular (LV) structure [end-diastolic (EDV) concentricity0.67...

The evaluation of adipose tissue distribution has become an essential component investigations on the complications obesity. However, a major limitation is lack methodology for accurate estimation mass in different regions body. Therefore, we have tested accuracy and precision magnetic resonance imaging (MRI) as method to measure body not accessible with standard anthropometric methods. subcutaneous intraabdominal estimated by MRI was compared that obtained direct weighing same compartments...

Although recent studies have suggested that blacks compared with whites an increased prevalence of left ventricular hypertrophy, it remains uncertain whether this is true despite adjustment for body composition (fat mass and fat-free mass) when assessed by cardiac MRI in the general population. The Dallas Heart Study a population-based study County which 1335 black 858 white participants 30 to 67 years age underwent detailed assessment including dual-energy x-ray absorptiometry scan measure...

Acute effects of exercise on MR imaging skeletal muscle in normal volunteersJL Fleckenstein, RC Canby, RW Parkey and RM PeshockAudio Available | Share

Several reports indicate that the body fat compartments, especially ip fat, predict metabolic risk better than total fat. The objective of study was to determine whether this can be confirmed and generalized throughout population.A representative sample 1934 Black White women men Dallas Heart Study participated in study.We measured body, trunk, lower with dual-energy x-ray absorptiometry abdominal compartments (sc, ip, retroperitoneal) magnetic resonance imaging. Other measurements included...

Abdominal obesity, particularly excess intraperitoneal fat, is considered to play a major role in causing insulin resistance and NIDDM. To determine if NIDDM patients accumulate whether this contributes significantly their resistance, 31 men with mild wide range of adiposity were compared 39 nondiabetic, control subjects for sensitivity (measured using euglycemic-hyperinsulinemic clamp technique [3-3H]glucose turnover) total regional (assessed by hydrodensitometry measuring subcutaneous...

The hypothesis that chronic kidney disease (CKD) is associated with increased coronary artery calcification (CAC) was tested using data from the Dallas Heart Study, a representative sample of County residents aged 30 to 65 yr. CKD defined as presence microalbuminuria and GFR ≥60 ml/min per 1.73 m2 (stage 1 2), or <60 3 5), excluding end-stage disease. Logistic regression used examine association between stages CAC scores >10, >100, >400 versus ≤10 compared no while adjusting for covariates....

The accuracy and reproducibility of magnetic resonance (MR) imaging in the determination left ventricular mass humans was investigated. Left wall volume measured from ten short-axis, end-diastolic MR images that spanned ventricle. Mass estimated on basis average an assumed myocardial density. To establish technique, authors imaged cadaver hearts compared true weight with estimate based findings. In vivo evaluated 40 subjects, resultant calculated masses 156.4-319.3 g. Intra- interobserver...

Prospective and retrospective magnetic resonance (MR) imaging (0.35-T) interpretations were compared with final diagnoses in 110 patients suspected to have osteomyelitis. Diagnostic criteria of dark marrow on T1-weighted images bright short-tau inversion-recovery yielded a prospective sensitivity 98% specificity 75%. Sixty percent uncomplicated septic joint effusions demonstrated abnormal signal intensity that was mistaken for Retrospective review revealed overall could be improved 82%...

Background In the patient with mitral regurgitation who is being considered for valvular surgery, cardiac catheterization usually performed to quantify severity of and determine its influence on left ventricular volumes systolic function. Magnetic resonance imaging (MRI) potentially provides a rapid, noninvasive method acquiring these data. Thus, this study was done whether MRI can reliably measure magnitude evaluate effect Methods Results Twenty-three subjects (14 women 9 men 15 72 years...

Background— Although gender-specific criteria are common for defining cardiac traits such as left ventricular hypertrophy, ejection fraction (LVEF) thresholds widely used in clinical practice have traditionally been the same women and men, perhaps because it remains uncertain whether there is a systematic difference LVEF between genders. Methods Results— Using magnetic resonance imaging probability-based sample of Dallas County residents aged 30 to 65 years (1435 1183 men), we compared men....

Recent studies from our group reveal that adipose tissue (AT) in the subcutaneous abdominal region is most important determinant of peripheral and hepatic insulin sensitivity. Because different anatomic physiologic characteristics anterior posterior AT, we investigated relationship masses each compartment, as determined by magnetic resonance imaging, to sensitivity (using euglycemic hyperinsulinemic glucose clamp technique), other anthropometric variables. Thirty‐four healthy men with...

Familial partial lipodystrophy, Dunnigan type (FPLD), is a rare autosomal dominant genetic disorder characterized by gradual loss of sc fat from the extremities, commencing at time puberty. Excess deposition may occur in face and neck area. Limited information available about adipose tissue distribution patients with FPLD. To investigate whether there unique pattern both affected men women FPLD, we performed whole-body magnetic resonance imaging one male three female two pedigrees. Magnetic...

Left ventricular hypertrophy (LVH) is traditionally classified as concentric or eccentric, based on the ratio of LV wall thickness to chamber dimension. We propose a 4-tiered LVH classification concentricity(0.67) (mass/end-diastolic volume(0.67)) and indexed end-diastolic volume (EDV).Cardiac MRI was performed in 2803 subjects (n=895) defined by increased mass/height(2.7). Increased EDV were at 97.5th percentile healthy subpopulation. Four geometric patterns resulted: concentricity without...

Sports-related muscle pain is frequent in both trained and untrained persons; however, its severity significance may be difficult to assess clinically. The authors used magnetic resonance (MR) imaging evaluate acute strains delayed-onset soreness sedentary subjects postmarathon myalgia runners. MR documented the distribution of affected muscles absence focal hematoma, fascial herniation, subsequent fibrosis, fatty infiltration. Pain associated with strain that occurring several days after...

Elevated levels of C-reactive protein (CRP) are associated with increased risk for incident cardiovascular events on the basis observations from several prospective epidemiological studies. However, less is known regarding relationship between CRP and atherosclerotic burden.We measured in 3373 subjects 30 to 65 years age who were participating Dallas Heart Study, a multiethnic, population-based, probability sample. Electron-beam CT scans used measure coronary artery calcification (CAC) 2726...

Background Velocity-encoded, phase-difference magnetic resonance imaging (MRI) has been shown to provide an accurate assessment of shunt magnitude in patients with large atrial septal defects, but its ability determine intracardiac left-to-right shunts various locations and sizes not evaluated a prospective blinded manner. The objective the present study was whether velocity-encoded, MRI can assess shunting humans. Methods Results Twenty-one subjects (15 women 6 men; age range, 15 72 years)...