Treatment of pediatric obesity.

The primary goal of childhood obesity interventions is regulation of body weight and fat with adequate nutrition for growth and development. Ideally, these interventions are associated with positive changes in the physiologic and psychological sequelae of obesity. To contribute to long-term weight maintenance, interventions should modify eating and exercise behaviors such that new, healthier behaviors develop and replace unhealthy behaviors, thereby allowing healthier behaviors to persist throughout development and into adulthood. This overview of pediatric obesity treatment, using predominantly randomized, controlled studies, highlights important contributions and developments in primarily dietary, activity, and behavior change interventions, and identifies characteristics of successful treatment and maintenance interventions. Potential positive (eg, reduction in blood pressure, serum lipids, and insulin resistance) and negative (eg, development of disordered eating patterns) side effects of treatment also are described. Recommendations for improving implementation of childhood obesity treatments, including application of behavioral choice theory, improving knowledge of response extinction and recovery in regards to behavior relapse, individualization of treatment, and integration of basic science with clinical outcome research, are discussed.

Predictors of child psychological changes during family-based treatment for obesity.

OBJECTIVE: To explore the influence of 1-year changes in child obesity and maternal psychopathology on changes in child psychological problems. DESIGN: Hierarchical regression models were used to predict child psychological change, with demographic variables, maternal psychological change, and child percentage overweight change as predictors. SETTING: Pediatric obesity research clinic. PARTICIPANTS: Clinic sample of 116 obese 8- to 12-year-old children and their mothers. INTERVENTIONS: Family-based behavioral weight-control program. MAIN OUTCOME MEASURES: Child psychopathology was assessed via mother-reported Child Behavior Checklists and maternal psychopathology was determined by standardizing scores on the Cornell Medical Index and the Symptoms Checklist-90-Revised. RESULTS: Significant improvements were observed in child percentage overweight (-20.1% overweight), and child and maternal psychopathology. Improved maternal psychopathology accounted for a significant amount of variance in improvements in the Child Behavior Checklist total Problems Scale and internalizing and externalizing problems subscales. Decreased obesity accounted for a significant amount of variance in improvements in the Total Competence scale and, somatic complaints, social problems and social competence subscales of the Child Behavior Checklist. Significant interactions of child obesity change by sex were found for Total Problems and externalizing scores. The interactions were due to girls with greater obesity reduction showing greater improvement in Total Problems, whereas boys with greater obesity reduction showed less improvement in externalizing problems. CONCLUSIONS: These results highlight the multidimensional nature of psychosocial functioning in obese children and call attention to multiple avenues for intervention to improve their psychosocial functioning.

Effects of decreasing sedentary behaviors on activity choice in obese children.

In this study, methods of decreasing highly preferred sedentary behaviors were compared and the consequent effects on activity choice were examined. Following free choice of sedentary and physical activities, 34 obese children either were positively reinforced for decreases in high-preference sedentary activity, were punished for high-preference sedentary activity, had access to high-preference sedentary activity restricted, or had no contingencies on activity (control group). Children randomized to reinforcement and punishment were more physically active on intervention days than the control group. Liking for targeted sedentary activity decreased in the reinforcement group, but increased in the restriction and control groups. Results suggest that reinforcing decreases in high-preference sedentary activity can increase physical activity and decrease liking for targeted sedentary activities.

The effect of dietary fat on salivary habituation and satiation.

This study was designed to explore the effect of dietary fat and carbohydrate on oral habituation. Forty women (18-21 years old) were randomized to 1 of 4 yogurt conditions that varied levels of dietary fat and carbohydrate. Subjects consumed 0.4 g of yogurt per pound per trial until they indicated fullness in up to 15 trials, with salivation, number of trials to fullness, and ratings of hedonics, appetite, and fullness measured. Subjects in the high-fat conditions demonstrated a significantly faster rate of salivary habituation than subjects in the low-fat conditions, and consumed less volume of yogurt but consumed more calories. The rate of habituation was not influenced by carbohydrate content of the yogurt. These findings suggest that oral habituation in humans is sensitive to macronutrient content of food.

Exercise in treating obesity in children and adolescents.

This paper reviews the use of exercise programs with obese children and adolescents. Studies included for review met two criteria: 1) children or adolescents were defined as obese using objective criteria for obesity, and 2) obese children or adolescents were provided either different types of exercise programs or an exercise program compared with a no-exercise control condition. Thirteen controlled outcome studies were identified. Experimental design, methods, and outcomes are presented and evaluated for each study. Factors that should be considered in research testing exercise interventions are discussed, including adherence, diet, age, gender, and type of exercise. In addition, the potential for exercise programs in the prevention of obesity in childhood and adolescence is discussed. The results support the continued use of exercise in combination with diet for child and adolescent obesity treatment, but the limited number of controlled studies indicates the need for more research in the area. The potential for exercise programs in the prevention of obesity in childhood and adolescence is discussed.

Evaluation of PTMSP membranes in achieving enhanced ethanol removal from fermentations by pervaporation.

The use of membrane processes for the recovery of fermentation products has been gaining increased acceptance in recent years. Pervaporation has been studied in the past as a process for simultaneous fermentation and recovery of volatile products such as ethanol and butanol. However, membrane fouling and low permeate fluxes have imposed limitations on the effectiveness of the process. In this study, we characterize the performance of a substituted polyacetylene membrane, poly[(l-trimethylsilyl)-l-propyne] (PTMSP), in the recovery of ethanol from aqueous mixtures and fermentation broths. Pervaporation using PTMSP membranes shows a distinct advantage over conventional poly(dimethyl siloxane) (PDMS) membranes in ethanol removal. The flux with PTMSP is about threefold higher and the concentration factor is about twofold higher than the corresponding performance achieved with PDMS under similar conditions. The performance of PTMSP with fermentation broths shows a reduction in both flux and concentration factor relative to ethanol-water mixtures. However, the PTMSP membranes indicate initial promise of increased fouling resistance in operation with cell-containing fermentation broths.

Soft x-ray images of the laser entrance hole of ignition hohlraums.

Hohlraums are employed at the national ignition facility to convert laser energy into a thermal x-radiation drive, which implodes a fusion capsule, thus compressing the fuel. The x-radiation drive is measured with a low spectral resolution, time-resolved x-ray spectrometer, which views the region around the hohlraum's laser entrance hole. This measurement has no spatial resolution. To convert this to the drive inside the hohlraum, the size of the hohlraum's opening ("clear aperture") and fraction of the measured x-radiation, which comes from this opening, must be known. The size of the clear aperture is measured with the time integrated static x-ray imager (SXI). A soft x-ray imaging channel has been added to the SXI to measure the fraction of x-radiation emitted from inside the clear aperture. A multilayer mirror plus filter selects an x-ray band centered at 870 eV, near the peak of the x-ray spectrum of a 300 eV blackbody. Results from this channel and corrections to the x-radiation drive are discussed.

Phosphodiesters as mycorrhizal P sources: II. Ericoid mycorrhiza and the utilization of nuclei as a phosphorus and nitrogen source by Vaccinium macrocarpon.

Mycorrhizal plants of Vaccinium mocrocarpon Aiton used nuclei from salmon sperm as a sole source of phosphorus (P) and achieved similar yields, P content and P concentration to plants crown with orthophosphate. Mycorrhizal infection significantly increased the effectiveness of utilization of both inorganic and organic (nuclei) sources of P by Vaccinium but in the case of the organic source this involved providing access to P which was completely unavailable to the uninfected plants. The results provide further support for the view that ericoid mycorrhizas have a crucial role in direct recycling of nutrients from organic matter, independent of the mineralizing activities of saprotrophic micro-organisms.

The association of maternal psychopathology and family socioeconomic status with psychological problems in obese children.

In an earlier study we found parental psychiatric symptoms to be a better correlate of behavioral problems in obese children than either child or parental obesity. This study sought to extend this research by assessing the association of general maternal distress, specific maternal psychopathology, family socioeconomic status and child obesity with the psychological problems of 152 children seeking treatment for obesity in two cohorts. Child psychological problems were measured using the Child Behavior Checklist/4-18 (CBCL) in each cohort. In sample 1 maternal general psychiatric symptoms were measured using the Cornell Medical Index (psychiatric subscales) and the Inventory of Interpersonal Problems whereas specific psychopathology was assessed with the Beck Depression Inventory and the Bulimia Test. In sample 2 the Symptom Checklist-90 and Binge Eating Scale provided general and specific measures of psychopathology. In the combined sample, 58% percent of the boys and 44% of the girls met criteria on at least one CBCL behavioral problem scale, with Social Problems the most prevalent problem in both boys and girls. For both samples, child obesity did not account for any variance in child psychosocial problems beyond that accounted for by maternal psychopathology and family SES. Family SES accounted for a significant increment in variance in child behavioral problems in only two scales. This study systematically replicates previous research, adding support for a broader conceptualization of factors that influence psychological problems in obese treatment-seeking children than one which focuses on child obesity.