Field evaluation of energy expenditure in women using Tritrac accelerometers

PURPOSE: To investigate the use of Tritrac accelerometers to measure energy expenditure (EE) of various activities for women in the field setting, as compared with portable indirect calorimetry. METHODS: Twenty women (age 20-29) performed a choreographed routine of six activities (walking, jogging, stair climbing, walking on an incline, stationary cycling, and arm ergometry) while wearing a Tritrac-R3D accelerometer (Hemokinetics Inc., Madison WI) and the Cosmed K4b(2) portable metabolic cart (Cosmed, Rome, Italy). RESULTS: Comparing the mean error scores (K4b(2) - Tritrac), the Tritrac overestimated the EE (kcal x min(-1)) of walking (-1.45) and jogging (-1.75), whereas underestimating the EE of stair climbing (2.76), stationary cycling (2.75), and arm ergometry (1.20). Walking on an incline showed the lowest mean error score (-0.11). Intraclass correlations were moderate for walking (r = 0.568, < 0.05), jogging (r = 0.666, < 0.05), and stairs (r = 0.503, < 0.05) but for the other activities ranged from r = 0.290 ( > 0.05) to r = 0.480 ( < 0.05). The raw data from the Tritrac was applied to a previously developed nonlinear model to adjust the Tritrac scores to the standard of whole-room indirect calorimetry. This resulted in statistically significant improvements in the agreement between the adjusted Tritrac value and the K4b for walking, jogging, and walking on an incline ( < 0.05). CONCLUSION: When compared with portable indirect calorimetry, the Tritrac overestimates the EE of walking and jogging, whereas underestimating that of stair climbing, stationary cycling, and arm ergometry. This limits the use of such a technique to measure EE in the field. The main issues appear to be the type and intensity of the activity and the need for movement in order for the Tritrac to register EE. Activity specific linear regression equations are proposed as a tool to improve the measurement of EE using the Tritrac in the field.     

Foot and ankle fractures in the industrial setting

Fractures of the ankle and foot are common in the worker. Proper initial assessment and treatment can result in a functional recovery that is prompt and complete in many cases. Many fractures, however, have a poor long-term prognosis and prolonged recovery. Frank initial discussions with the patient and case manager can help the system better manage the patient's future.     

Effects of moderate alcohol intake on fasting insulin and glucose concentrations and insulin sensitivity in postmenopausal women: a randomized controlled trial

CONTEXT: Epidemiologic data demonstrate that moderate alcohol intake is associated with improved insulin sensitivity in nondiabetic individuals. No controlled-diet studies have addressed the effects of daily moderate alcohol consumption on fasting insulin and glucose concentrations and insulin sensitivity. OBJECTIVE: To determine whether daily consumption of low to moderate amounts of alcohol influences fasting insulin and glucose concentrations and insulin sensitivity in nondiabetic postmenopausal women. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled crossover trial of 63 healthy postmenopausal women, conducted at a clinical research center in Maryland between 1998 and 1999. INTERVENTIONS: Participants were randomly assigned to consume 0, 15, or 30 g/d of alcohol for 8 weeks each as part of a controlled diet. All foods and beverages were provided during the intervention. An isocaloric beverage was provided in the 0-g/d arm. Energy intake was adjusted to maintain constant body weight. MAIN OUTCOME MEASURES: Fasting insulin, triglyceride, and glucose concentrations, measured at the end of each dietary period; insulin sensitivity, estimated with a published index of glucose disposal rate corrected for fat-free mass based on fasting insulin and fasting triglyceride concentrations, compared among treatments with a mixed-model analysis of variance. RESULTS: A complete set of plasma samples was collected and analyzed for 51 women who completed all diet treatments. Consumption of 30 g/d of alcohol compared with 0 g/d reduced fasting insulin concentration by 19.2% (P =.004) and triglyceride concentration by 10.3% (P =.001), and increased insulin sensitivity by 7.2% (P =.002). Normal-weight, overweight, and obese individuals responded similarly. Only fasting triglyceride concentration was significantly reduced when comparing 0 and 15 g/d of alcohol (7.8%; P =.03), and no difference was found between consumption of 15 and 30 g/d of alcohol; however, there was a significant linear trend (P =.001). Fasting glucose concentrations were not different across treatments. CONCLUSIONS: Consumption of 30 g/d of alcohol (2 drinks per day) has beneficial effects on insulin and triglyceride concentrations and insulin sensitivity in nondiabetic postmenopausal women.     

Intracellular accumulation and reduced sarcolemmal expression of dysferlin in limb--girdle muscular dystrophies

Dysferlin has recently been identified as a novel gene involved in limb-girdle muscular dystrophy type 2B (LGMD2B) and its allelic disease, Miyoshi myopathy. The predicted structure of dysferlin suggests that it is a transmembrane protein possibly involved in membrane fusion. Thus, unlike previously identified structural proteins in muscular dystrophy, dysferlin is likely involved in a novel pathogenic mechanism for this disease. In this study, we have analyzed the expression of dysferlin in skeletal muscle of patients with disruptions in the dystrophin-glycoprotein complex and patients with a clinical diagnosis of LGMD2B or Miyoshi myopathy. We show expression of dysferlin at the sarcolemma in normal muscle and reduced sarcolemmal expression along with accumulation of intracellular staining in dystrophic muscle. Electron microscopy in Miyoshi myopathy biopsies suggests that the cytoplasmic staining could be a result of the abundance of intracellular vesicles. Our results indicate that dysferlin expression is perturbed in LGMD and that both mutations in the dysferlin gene and disruption of the dystrophin-glycoprotein complex can lead to the accumulation of dysferlin within the cytoplasm.     

Transvaginal ultrasound examination of women with and without pelvic venous congestion

AIM: To determine if transvaginal ultrasound, including power Doppler examination, can distinguish between women with and without pelvic congestion.MATERIALS AND METHODS: Thirty-six women with pelvic congestion were prospectively examined using transvaginal ultrasonography and standard uterine and ovarian measurements made. Additionally, planimetric measurements of each ovary were taken using an image analysis program to determine the cross-sectional area of ovarian stroma and follicles, if any. Power Doppler images of adnexal vessels were obtained and planimetric estimates of surface area calculated. A congestion score was assigned to each patient, based on vein number, diameter and morphology on grey-scale scanning. Identical measurements were obtained from 19 asymptomatic women and results compared.RESULTS: There was no significant difference between women with pelvic congestion and controls with respect to power Doppler or grey-scale images of adnexal vessels, or congestion score. However, women with pelvic congestion had significantly larger and multicystic ovaries when compared to controls.CONCLUSIONS: Transvaginal ultrasound measurements of adnexal vasculature, including power Doppler measurements, cannot reliably distinguish women with pelvic congestion from controls. However, ultrasound may remain useful for diagnosis of pelvic congestion, predominantly because it is able to visualize multi-cystic ovaries in these patients.     

Effects of luminance and resolution on observer performance with chest radiographs

PURPOSE: To examine the combined effects of image resolution and display luminance on observer performance for detection of abnormalities depicted on posteroanterior chest radiographs. MATERIALS AND METHODS: A total of 529 radiographs were displayed on a specially constructed view box at three luminance levels (770, 260, and 85 cd/m(2)) and three resolutions (100-microm, 200-microm, and 400-microm pixels). Each image was reviewed nine times by six radiologists who participated in this study. The abnormalities included nodule, pneumothorax, interstitial disease, alveolar infiltrates, and rib fracture. Negative (normal) radiographs were also included. RESULTS: Receiver operating characteristic curves indicated that the effect of image luminance was greater than that of resolution. The detection of pneumothorax, interstitial disease, and rib fracture showed statistically significant differences (P <. 05) due to luminance. The detection of pneumothorax was the only abnormality with a statistically significant difference due to resolution. There was no evidence that luminance was related to image resolution for any of the abnormalities. CONCLUSION: At a resolution of 400-microm pixels or higher across the field of view and a luminance of 260 cd/m(2) or more, primary diagnosis with posteroanterior chest radiographs is not likely to be affected by the quality of display.     

The effect of aerobic exercise training on the lipid-lipoprotein profile of children and adolescents

Longitudinal paediatric population studies have provided evidence that the risk factor theory may be extended to children and adolescents. These studies could assist in identifying individuals at increased coronary risk. Numerous studies have focused on the effects of regular exercise on the paediatric lipoprotein profile, a recognised primary risk factor, with equivocal results. Cross-sectional comparisons of dichotomised groups provide the strongest evidence of an exercise effect. 'Trained' or 'active' children and adolescents demonstrate 'favourable' levels of high density lipoprotein-cholesterol (HDL-C), triacylglycerol, total cholesterol (TC)/HDL-C and low density lipoprotein-cholesterol (LDL-C)/HDL-C, whilst TC is generally unaffected. The evidence regarding LDL-C in these studies is equivocal. A possible self-selection bias means that a cause-effect relationship between exercise and the lipoprotein profile cannot be readily established from this design. Correlational studies are difficult to interpret because of differences in participant characteristics, methods employed to assess peak oxygen uptake and habitual physical activity (HPA), and the statistical techniques used to analyse multivariate data. Directly measured cardiorespiratory fitness does not appear to be related to lipoprotein profiles in the children and adolescents studied to date, although there are data to the contrary. The relationship with HPA is more difficult to decipher. The evidence suggests that a 'favourable' lipoprotein profile may be related to higher levels of HPA, although differences in assessment methods preclude a definitive answer. While few prospective studies exist, the majority of these longitudinal investigations suggest that imposed regular exercise has little, if any, influence on the lipoprotein levels of children and adolescents. However, most prospective studies have several serious methodological design weaknesses, including low sample size, inadequate exercise training volume and a lack of control individuals. Recent studies have suggested that increases in HDL-C and reductions in LDL-C may be possible with regular exercise. The identification of a dose-response relationship between exercise training and the lipoprotein profile during the paediatric years remains elusive.