33 research outputs found

    Skeletal muscle characteristics and motor performance after 2-year growth hormone treatment in adults with prader-willi syndrome.

    Get PDF
    Context:In adults with Prader-Willi syndrome (PWS), abnormal body composition with decreased lean body mass and skeletal muscle (SM) volume has been related to altered GH secretion and may possibly contribute to greatly reduced motor capacity.Objective:The scope of the study was to test the hypothesis that GH treatment has favorable effects on SM characteristics and motor performance in adults with PWS.Design, Setting, and Participants:Fifteen obese PWS subjects (nine males and six females; age range, 19–35 y; body mass index, 37.7–59.9 kg/m2) were investigated before and after 12 (GH12) and 24 (GH24) months of GH treatment.Main Outcome Measures:SM cross-sectional area and SM attenuation were determined with computed tomography at the lumbar and midthigh levels. Maximal isometric handgrip strength and isokinetic knee extension peak torque were measured. Motor performance was evaluated with different indoor walking tests, whereas exercise endurance was assessed with a treadmill incremental test to exhaustion.Results:A condition of severe GH deficiency was found in six patients (40%). GH treatment significantly increased lean body mass (GH12, P < .05; GH24, P < .05), reduced percentage of body fat (GH12, P < .05; GH24, P < .05), and augmented SM cross-sectional area and SM attenuation of both lumbar (GH12, P < .01; GH24, P < .001) and thigh muscles (GH24, P < .05). Handgrip strength increased by 7% at GH12 (P < .05) and by 13% at GH24 (P < .001). Peak torque of knee extension extrapolated at zero angular velocity was significantly higher at GH24 (P < .01), and exercise endurance rose by 13% (P < .05) and 17% (P < .05) before exhaustion at GH12 and GH24, respectively, whereas no change was detected with walking tests. No significant difference in the response to GH treatment was detected between patients with and without GH deficiency.Conclusion:Long-term GH treatment in adult PWS patients improves body composition and muscle size and quality and increases muscle strength and exercise tolerance independently from the GH secretory status

    Tuning electrical properties of hierarchically assembled Al-doped ZnO nanoforests by room temperature Pulsed Laser Deposition

    Get PDF
    Large surface area, 3D structured transparent electrodes with effective light management capability may represent a key component in the development of new generation optoelectronic and energy harvesting devices. We present an approach to obtain forest-like nanoporous/hierarchical Al-doped ZnO conducting layers with tunable transparency and light scattering properties, by means of room temperature Pulsed Laser Deposition in a mixed Ar:O2 atmosphere. The composition of the background atmosphere during deposition can be varied to modify stoichiometry-related defects, and therefore achieve control of electrical and optical properties, while the total background pressure controls the material morphology at the nano- and mesoscale and thus the light scattering properties. This approach allows to tune electrical resistivity over a very wide range (10^-1 - 10^6 Ohm*cm), both in the in-plane and cross-plane directions. Optical transparency and haze can also be tuned by varying the stoichiometry and thickness of the nano-forests

    Tuning of Electrical and Optical Properties of Highly Conducting and Transparent Ta-Doped TiO2 Polycrystalline Films

    Get PDF
    We present a detailed study on polycrystalline transparent conducting Ta-doped TiO2 films, obtained by room temperature pulsed laser deposition followed by an annealing treatment at 550°C in vacuum. The effect of Ta as a dopant element and of different synthesis conditions are explored in order to assess the relationship between material structure and functional properties, i.e. electrical conductivity and optical transparency. We show that for the doped samples it is possible to achieve low resistivity (of the order of 5×10-4 Ωcm) coupled with transmittance values exceeding 80% in the visible range, showing the potential of polycrystalline Ta:TiO2 for application as a transparent electrode in novel photovoltaic devices. The presence of trends in the structural (crystalline domain size, anatase cell parameters), electrical (resistivity, charge carrier density and mobility) and optical (transmittance, optical band gap, effective mass) properties as a function of the oxygen background pressures and laser fluence used during the deposition process and of the annealing atmosphere is discussed, and points towards a complex defect chemistry ruling the material behavior. The large mobility values obtained in this work for Ta:TiO2 polycrystalline films (up to 13 cm2V-1s-1) could represent a definitive advantage with respect to the more studied Nb-doped TiO2

    Prader-Willi syndrome: A primer for clinicians

    Get PDF
    The advent of sensitive genetic testing modalities for the diagnosis of Prader-Willi syndrome has helped to define not only the phenotypic features of the syndrome associated with the various genotypes but also to anticipate clinical and psychological problems that occur at each stage during the life span. With advances in hormone replacement therapy, particularly growth hormone children born in circumstances where therapy is available are expected to have an improved quality of life as compared to those born prior to growth hormone

    Psychological Well-Being as an Independent Predictor of Exercise Capacity in Cardiac Rehabilitation Patients With Obesity

    Get PDF
    Objective: Exercise capacity (EC) is a well-established predictor of cardiovascular health. It is notoriously influenced by several factors, but the independent effect of psychological well-being (PWB) on EC has not yet been explored. The present study aims to investigate (1) whether PWB is an independent predictor of EC over and above selected demographic, behavioral, and biomedical parameters in a sample of CR patients with obesity and (2) whether PWB is a stronger predictor of EC than the other variables. Methods: Data from 1968 patients were collected at the time of their inclusion in a cardiac rehabilitation (CR) program and retrospectively analyzed in a cross-sectional study. Since cardiorespiratory parameters defined in normal weight populations differ from those of their obese counterparts, an ad hoc validated formula taking body mass index (BMI) into consideration was used to predict EC. Results: A multiple regression analysis revealed left ventricular eject fraction (LVEF) to be the strongest predictor of EC, followed by PWB, type 2 diabetes (DM), smoking status, atrial fibrillation (AF), and education. Bayesian evaluation of informative hypotheses corroborated LVEF as the best predictor of EC, and confirmed the superiority of PWB over and above DM and smoking status in influencing EC. Conclusion: These findings strengthen the link between psychological and physical health, suggesting a better PWB is associated with greater EC. Prompt screening of a patient’s mood and readiness to perform an active lifestyle would therefore enhance the long-term health benefits of CR

    Growth hormone therapy improves exercise capacity in adult patients with Prader-Willi syndrome

    No full text
    none6BACKGROUND: Prader-Willi syndrome (PWS) is associated with an inappropriate proportion of fat mass (FM) to non-FM compared to simple obesity. Altered body composition in PWS resembles that seen in subjects with GH deficiency, in which a reduction of lean body mass (LBM) is observed. The low LBM may contribute to the reduced motor skills seen in PWS patients. AIM: The objective of the study was to investigate the effects of GH therapy on exercise capacity and body composition in a group of adult subjects with PWS. SUBJECTS AND METHODS: Twelve PWS adults (7 males and 5 females, aged 26.4+/-4.4 yr, body mass index 44.3+/-4.6 kg/m2) participated in the study. Body composition analysis and exercise stress test were carried out throughout the 12 months GH therapy. Body composition was measured by Dual Energy X-ray Absorptiometry. Physical performance was evaluated using treadmill exercise test. Exercise intensity was expressed as metabolic equivalents (MET, 1 MET= 3.5 ml O2 kg(-1) min(-1)). Statistical analysis was performed by repeated-measures analysis of variance followed by post-hoc analysis with t test for paired data for comparisons among the different follow ups. RESULTS: Compared to baseline GH therapy increased LBM at 6 (p<0.0001) and 12 months (p<0.005) (45.3+/-7.7 kg vs 48.6+/-6.7 kg vs 48.2+/-7.5 kg). FM% was significantly reduced both after 6 and 12 months (p<0.02) (56.1+/-4.8% vs 53.7+/-4.2% vs 53.3+/-4.8%). Attained MET were found to be improved by 16% after 6 months and by 19% after 12 months of GH (p<0.001), while the small further rise between 6 and 12 months was not significant. CONCLUSIONS: Our findings seem to support the view that GH therapy has beneficial effects on physical activity and agility as well as on body composition of adult patients with PWS.noneGONDONI LA; VISMARA L; MARZULLO P; VETTOR R.; LIUZZI A; GRUGNI GGondoni, La; Vismara, L; Marzullo, P; Vettor, Roberto; Liuzzi, A; Grugni, G

    Psychological well-being in obese in-patients with ischemic heart disease at entry and at discharge from a four-week cardiac rehabilitation program

    No full text
    The purposes of this observational pre-post study were twofold: 1- to evaluate psychological health in obese patients with ischemic heart disease at admission to cardiac rehabilitation (CR) and 2 - to examine the effectiveness of a 4-week CR residential program in improving obese patients' psychological well-being at discharge from CR. A sample of 177 obese patients completed the Psychological General Well-Being Inventory (PGWBI) at admission to the CR program and at discharge. The equivalence testing method with normative comparisons was used to determine the clinical significance of improvements after having established that baseline mean scores on the PGWBI scales were significantly lower than normal means. Results show that patients scored equally or better than norms on many PGWBI dimensions at admission to CR but scored significantly worse on Global Score, Vitality and Self-control. At discharge, mean scores that were impaired at baseline returned to normal levels at the more conservative equivalence interval. A 4-week CR program was thus effective in improving obese patients' psychological well-being. The equivalence testing method allowed to establish the clinical significance of such improvement
    corecore