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BACKGROUND AND PURPOSE: Patients with Duchenne muscular dystrophy (DMD) change their movement patterns to compensate for muscle weakness. The Duchenne Video Assessment (DVA) measures ease of movement through evaluation of compensatory movements. The DVA directs caregivers to video record patients performing home-based movement tasks using a mobile application, and DVA-certified physical therapists evaluate the videos using scorecards with prespecified compensatory movement criteria. Two qualitative interview studies were conducted to select movement tasks for the DVA that are relevant to patients with DMD and able to reflect changes in function. METHODS: Qualitative interviews with eligible physical therapists were conducted remotely. Physical therapists were asked to spontaneously suggest movement tasks prior to evaluating specific movement tasks selected a priori. Analysts conducted a content analysis to investigate whether movement tasks selected a priori were confirmed as relevant to the population of interest and able to show changes in function. RESULTS: The studies included five physical therapists to select tasks for ambulatory patients with DMD and six for non-ambulatory patients. For an ambulatory population, all five experts confirmed Climb Five Stairs, Run, Stand Up from Sitting, Sit Up from Supine, and Jump Forward, and four (80%) confirmed Walk as relevant and able to show functional changes. For a non-ambulatory population, all six experts confirmed Eat 10 Bites, Roll Over in Bed, Shift Weight in Bed, Take T-Shirt Off, Put T-Shirt On, Put Arms on Armrest, and Reach Across Table to Grab Cell Phone, and five (83%) confirmed Raise Hands Above Head as relevant and able to show functional changes. DISCUSSION: Physical therapists confirmed the DVA movement tasks as relevant to patients with DMD and able to reflect changes in function. The use of the DVA in clinical trials provides an opportunity to collect data not seen in clinic and reduce travel burden for families.
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The relative influence of genetics and the environment on factors associated with cardiovascular disease (CVD) and metabolic syndrome (MetS) remains unclear. We performed model-fitting analyses to quantify genetic, common environmental, and unique environmental variance components of factors associated with CVD and MetS [waist circumference, blood pressure, fasting plasma glucose and insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and fasting plasma lipids] in adult male and female monozygotic twins reared apart or together. We also investigated whether MetS components share common influences. Plasma cholesterol and triglyceride concentrations were highly heritable (56-77%, statistically significant). Waist circumference, plasma glucose and insulin, HOMA-IR, and blood pressure were moderately heritable (43-57%, statistically significant). Unique environmental factors contributed to the variance of all variables (20-38%, perforce statistically significant). Common environmental factors contributed 23, 30, and 42% (statistically significant) of the variance of waist circumference, systolic blood pressure, and plasma glucose, respectively. Two shared factors influenced MetS components; one influenced all components except HDL cholesterol, another influenced only lipid (triglyceride and HDL cholesterol) concentrations. These results suggest that genetic variance has a dominant influence on total variance of factors associated with CVD and MetS and support the proposal of one or more underlying pathologies of MetS.
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Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Ambiente , Síndrome Metabólico/epidemiología , Síndrome Metabólico/genética , Adolescente , Adulto , Anciano , Análisis de Varianza , Enfermedades Cardiovasculares/metabolismo , Estudios Transversales , Metabolismo Energético , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Síndrome Metabólico/metabolismo , Persona de Mediana Edad , Factores de Riesgo , Gemelos Monocigóticos/genética , Gemelos Monocigóticos/metabolismo , Adulto JovenRESUMEN
Exercise has well-recognized health benefits, including reduction in risk factors for cardiovascular disease and type 2 diabetes. However, the extent to which exercise influences energy regulation and facilitates a reduction in body fat is less clear. This review summarizes published studies on the effects of different amounts of exercise on body fatness, energy intake, and food preferences in humans. The results show consistent effects of exercise on body fatness in the absence of prescribed dietary change, with a progressive loss of body fat associated with higher exercise energy expenditures in both men and women. In part, these effects appear to be mediated by a spontaneous reduction in hunger associated with participation in exercise. Insufficient data are available on whether there are changes in food preferences and taste perception that influence energy balance through macronutrient selection, so further studies in this area are needed.
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Adiposidad/fisiología , Ingestión de Energía/fisiología , Ejercicio Físico/fisiología , Composición Corporal/fisiología , Preferencias Alimentarias , HumanosRESUMEN
The purpose of this study was to determine the contents of three forms of vitamin K [phylloquinone, dihydrophylloquinone, and menaquinone-4 (MK-4)] in representative samples (including different samples within the same food category) of meat (n = 128), dairy and eggs (n = 24), and fast foods (n = 169) common to the U.S. diet. The findings of our analysis indicate that no single food item in these categories is a rich dietary source of any one form of vitamin K. However, these foods are often consumed in large quantities; hence, they may be of importance in overall contribution to total vitamin K intake. The presence of MK-4 in meat, eggs, and dairy foods could be important as physiologic functions unique to MK-4 are identified.
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Productos Lácteos/análisis , Dieta , Análisis de los Alimentos , Carne/análisis , Vitamina K/análisis , Animales , Restaurantes , Estados Unidos , Vitamina K 1/análisis , Vitamina K 2/análogos & derivados , Vitamina K 2/análisisRESUMEN
This study examined the relative influence of genetic versus environmental factors on specific aspects of eating behavior. Adult monozygotic twins (22 pairs and 3 singleton reared apart, 38 pairs and 9 singleton reared together, age 18-76 years, BMI 17-43 kg/m2) completed the Three Factor Eating Questionnaire. Genetic and environmental variance components were determined for the three eating behavior constructs and their subscales using model-fitting univariate and multivariate analyses. Unique environmental factors had a substantial influence on all eating behavior variables (explaining 45-71% of variance), and most strongly influenced external locus for hunger and strategic dieting behavior of restraint (explaining 71% and 69% of variance, respectively). Genetic factors had a statistically significant influence on only 4 variables: restraint, emotional susceptibility to disinhibition, situational susceptibility to disinhibition, and internal locus for hunger (heritabilities were 52%, 55%, 38% and 50%, respectively). Common environmental factors did not statistically significantly influence any variable assessed in this study. In addition, multivariate analyses showed that disinhibition and hunger share a common influence, while restraint appears to be a distinct construct. These findings suggest that the majority of variation in eating behavior variables is associated with unique environmental factors, and highlights the importance of the environment in facilitating specific eating behaviors that may promote excess weight gain.
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Heritability estimates of human body fatness vary widely and the contribution of body composition methodology to this variability is unknown. The effect of body composition methodology on estimations of genetic and environmental contributions to body fatness variation was examined in 78 adult male and female monozygotic twin pairs reared apart or together. Body composition was assessed by six methods - body mass index (BMI), dual energy x-ray absorptiometry (DXA), underwater weighing (UWW), total body water (TBW), bioelectric impedance (BIA), and skinfold thickness. Body fatness was expressed as percent body fat, fat mass, and fat mass/height2 to assess the effect of body fatness expression on heritability estimates. Model-fitting multivariate analyses were used to assess the genetic and environmental components of variance. Mean BMI was 24.5 kg/m2 (range of 17.8-43.4 kg/m2). There was a significant effect of body composition methodology (p<0.001) on heritability estimates, with UWW giving the highest estimate (69%) and BIA giving the lowest estimate (47%) for fat mass/height2. Expression of body fatness as percent body fat resulted in significantly higher heritability estimates (on average 10.3% higher) compared to expression as fat mass/height2 (p=0.015). DXA and TBW methods expressing body fatness as fat mass/height2 gave the least biased heritability assessments, based on the small contribution of specific genetic factors to their genetic variance. A model combining DXA and TBW methods resulted in a relatively low FM/ht2 heritability estimate of 60%, and significant contributions of common and unique environmental factors (22% and 18%, respectively). The body fatness heritability estimate of 60% indicates a smaller contribution of genetic variance to total variance than many previous studies using less powerful research designs have indicated. The results also highlight the importance of environmental factors and possibly genotype by environmental interactions in the etiology of weight gain and the obesity epidemic.