PubMed Health⌕ Search

Biomedical subjects

Gary D Foster

Publications and source records attributed to Gary D Foster.

At least 19 recordsLinked to original sources

Correlates of health-related quality of life in overweight and obese adults with type 2 diabetes.

OBJECTIVE: This paper describes and examines conceptually relevant correlates of health-related quality of life (HRQL) in overweight or obese persons with type 2 diabetes. Research Design and Procedures: The investigation was a cross-sectional study of 5145 overweight or obese adults with type 2 diabetes between the ages of 45 and 74 years. Analyses examined the relationship that demographic characteristics, disease burden, and cardiovascular fitness had with HRQL: the Short Form 36 (SF-36) and the Beck Depression Inventory (BDI) II. RESULTS: Means for the SF-36 physical component summary (PCS) scores, the mental component summary scores, and the BDI-II were as follows: 47.0, 54.0, and 5.7. Less desirable PCS scores were related to several comorbidities, insulin use, physical complaints, a high BMI, low metabolic equivalent (MET) capacity, and lower education. Interactions between categories of obesity and MET capacity revealed that greater BMI was related to lower PCS scores when individuals had lower MET capacities yet was absent for those individuals who had higher MET capacities. In addition, although greater BMI was associated with more severe depressive symptomatology, this association was the most dramatic for those with class III obesity who had low MET capacity. DISCUSSION: Although participants in Look AHEAD had a favorable profile on the SF-36 and the BDI-II at baseline, lower PCS scores were related to disease severity and the presence of other comorbidities. More important, although the temporal ordering of associations cannot be determined in a cross-sectional design, the interactions between obesity class and MET capacity suggest that the adverse effect of BMI on PCS and BDI-II scores may be buffered by higher MET capacities.

Aged↗

Expression of laccase gene lcc1 in Coprinopsis cinerea under control of various basidiomycetous promoters.

Coprinopsis cinerea laccase gene lcc1 was expressed in this basidiomycete under naturally non-inductive conditions using various homologous and heterologous promoters. Laccase expression was achieved in solid and liquid media with promoter sequences from the C. cinerea tub1 gene, the Agaricus bisporus gpdII gene, the Lentinus edodes priA gene and the Schizophyllum commune Sc3 gene. As measured by enzyme activity in liquid cultures, a 277-bp gpdII promoter fragment, followed by a 423-bp priA fragment, was most efficient. A shorter priA sequence of 372 bp was inactive. tub1 promoter fragments were reasonably active, whereas the S. commune Sc3 promoter sequence was less active, in comparison. Irrespective of the promoter used, addition of copper to the medium increased enzymatic activities for highly active transformants by 10- to 50-fold and for less active transformants for 2- to 7-fold. The highest enzymatic activities (3 U/ml) were reached with the gpdII promoter in the presence of 0.1 mM CuSO(4).

Basidiomycota↗

Behavioral treatment of obesity.

Behavioral treatment is an approach used to help individuals develop a set of skills to achieve a healthier weight. It is more than helping people to decide what to change; it is helping them identify how to change. The behavior change process is facilitated through the use of self-monitoring, goal setting, and problem solving. Studies suggest that behavioral treatment produces weight loss of 8-10% during the first 6 mo of treatment. Structured approaches such as meal replacements and food provision have been shown to increase the magnitude of weight loss. Most research on behavioral treatment has been conducted in university-based clinic programs. Although such studies are important, they tell us little about the effectiveness of these approaches in settings outside of specialized clinics. Future research might focus more on determining how these behavioral techniques can be best applied in a real-world setting.

Behavior Therapy↗

Promoting more modest weight losses: a pilot study.

OBJECTIVE: This pilot study assessed the short- and long-term effects of a modified cognitive behavioral treatment designed to facilitate obese patients' acceptance of a 5% to 10% reduction in initial weight. RESEARCH METHODS AND PROCEDURES: Participants were 17 women with a mean age of 46.5 +/- 9.7 years and BMI of 34.7 +/- 2.9 kg/m2. They participated in a 40-week program that included four phases. The first discussed the benefits of modest weight losses and the potential adverse effects of unrealistic expectations. Phase II provided instruction in traditional cognitive behavioral methods of weight control Phase III focused on methods to improve body image and self-esteem. Phase IV addressed skills for weight maintenance. Changes in weight, self-esteem, body image, and quality of life were assessed at the end of treatment and 1 year later (week 92). RESULTS: At week 40, participants lost an average of 5.7 +/- 5.3% of initial weight, which was associated with significant improvements in body image, self-esteem, and quality of life. Improvements in psychosocial status were maintained at week 92, although mean weight loss at this time had declined to 2.9 +/- 5.6% of initial weight. Increased satisfaction with body weight at week 40 was associated with significantly better maintenance of weight loss at follow-up (r = -0.70; p = 0.02). DISCUSSION: Having participants seek only modest initial weight losses does not appear to facilitate weight maintenance. However, increasing patients' satisfaction with their body weight at the end of treatment may help improve weight maintenance. More research is needed on the relation between satisfaction with initial weight loss and long-term success.

Adult↗

Dieting and the development of eating disorders in obese women: results of a randomized controlled trial.

BACKGROUND: Some investigators fear that dieting may precipitate binge eating and other adverse behavioral consequences. OBJECTIVE: The objective of the study was to examine whether dieting would elicit binge eating and mood disturbance in individuals free of these complications before treatment. DESIGN: A total of 123 obese women were randomly assigned to 1) a 1000 kcal/d diet that included 4 servings/d of a liquid meal replacement (MR); 2) a 1200-1500 kcal/d balanced deficit diet (BDD) of conventional foods; or 3) a nondieting (ND) approach that discouraged energy restriction. All women attended weekly group sessions for 20 wk and biweekly sessions from week 20 to week 40. RESULTS: At week 20, participants in the MR, BDD, and ND groups lost 12.1 +/- 6.7%, 7.8 +/- 6.0%, and 0.1 +/- 2.4% of initial weight, respectively (P < 0.001). During the first 20 wk, there were no significant differences among groups in the number of persons who had objective binge episodes or in reports of hunger or dietary disinhibition. Symptoms of depression decreased significantly more (P < 0.001) in the MR and BDD groups than in ND participants. At week 28, significantly more (P < 0.003) cases of binge eating were observed in MR participants than in the 2 other groups. No differences, however, were observed between groups at weeks 40 or 65 (a follow-up visit). At no time did any participant meet criteria for binge-eating disorder. CONCLUSION: Concerns about possible adverse behavioral consequences of dieting should not dissuade primary care providers from recommending modest energy restriction to obese individuals.

Adult↗

A randomized trial of a low-carbohydrate diet for obesity.

BACKGROUND: Despite the popularity of the low-carbohydrate, high-protein, high-fat (Atkins) diet, no randomized, controlled trials have evaluated its efficacy. METHODS: We conducted a one-year, multicenter, controlled trial involving 63 obese men and women who were randomly assigned to either a low-carbohydrate, high-protein, high-fat diet or a low-calorie, high-carbohydrate, low-fat (conventional) diet. Professional contact was minimal to replicate the approach used by most dieters. RESULTS: Subjects on the low-carbohydrate diet had lost more weight than subjects on the conventional diet at 3 months (mean [+/-SD], -6.8+/-5.0 vs. -2.7+/-3.7 percent of body weight; P=0.001) and 6 months (-7.0+/-6.5 vs. -3.2+/-5.6 percent of body weight, P=0.02), but the difference at 12 months was not significant (-4.4+/-6.7 vs. -2.5+/-6.3 percent of body weight, P=0.26). After three months, no significant differences were found between the groups in total or low-density lipoprotein cholesterol concentrations. The increase in high-density lipoprotein cholesterol concentrations and the decrease in triglyceride concentrations were greater among subjects on the low-carbohydrate diet than among those on the conventional diet throughout most of the study. Both diets significantly decreased diastolic blood pressure and the insulin response to an oral glucose load. CONCLUSIONS: The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets.

Adult↗

Physical activity and its effects on lipids.

Physical activity is an important component of weight control, and is widely recommended to prevent and treat obesity-related complications such as diabetes and coronary heart disease (CHD). Although the cardiovascular benefits of increased physical activity are likely multifactorial, much of the attention has been focused on the known high-density lipoprotein (HDL) cholesterol-raising properties of regular physical activity. Physical activity, however, can also reliably lower triglycerides and favorably affect both low-density lipoprotein (LDL) and HDL particle sizes. Limited data on resistance exercise suggest that this type of physical activity may reduce LDL cholesterol. Although these lipid effects are modest and variable, they are likely to be particularly important in reducing the morbidity and mortality from CHD on a population level, and may be especially important in patients with atherogenic dyslipidemia.

Cardiovascular Diseases↗

Look AHEAD (Action for Health in Diabetes): design and methods for a clinical trial of weight loss for the prevention of cardiovascular disease in type 2 diabetes.

Overweight and obesity are major contributors to both type 2 diabetes and cardiovascular disease (CVD). Moreover, individuals with type 2 diabetes who are overweight or obese are at particularly high risk for CVD morbidity and mortality. Although short-term weight loss has been shown to ameliorate obesity-related metabolic abnormalities and CVD risk factors, the long-term consequences of intentional weight loss in overweight or obese individuals with type 2 diabetes have not been adequately examined. The primary objective of the Look AHEAD clinical trial is to assess the long-term effects (up to 11.5 years) of an intensive weight loss program delivered over 4 years in overweight and obese individuals with type 2 diabetes. Approximately 5000 male and female participants who have type 2 diabetes, are 45-74 years of age, and have a body mass index >or=25 kg/m(2) will be randomized to one of the two groups. The intensive lifestyle intervention is designed to achieve and maintain weight loss through decreased caloric intake and increased physical activity. This program is compared to a control condition given diabetes support and education. The primary study outcome is time to incidence of a major CVD event. The study is designed to provide a 0.90 probability of detecting an 18% difference in major CVD event rates between the two groups. Other outcomes include components of CVD risk, cost and cost-effectiveness, diabetes control and complications, hospitalizations, intervention processes, and quality of life.

Aged↗

Investigating the role of a Verticillium fungicola beta-1,6-glucanase during infection of Agaricus bisporus using targeted gene disruption.

Studies on the mycopathogen Verticillium fungicola have shown the up-regulation of beta-1,6-glucanases when grown in the presence of host cell walls and host cell wall components including chitin. These cell-wall-degrading enzymes are hypothesized to contribute to the pathogenic ability of mycopathogens. A beta-1,6-glucanase gene, VfGlu1, showing high similarity to beta-1,6-glucanase genes from Hypocrea virens, Neotyphodium sp., and Trichoderma harzianum, was isolated using degenerate PCR from V. fungicola, a serious mycopathogen of the cultivated mushroom Agaricus bisporus. Agrobacterium-mediated transformation of V. fungicola using homologous DNA from VfGlu1 resulted in homologous integration at the VfGlu1 locus in 75% of transformants, generating mutants disrupted in the VfGlu1 gene. VfGlu1 mutants displayed reduced virulence and diminished ability to utilize chitin as a carbon source, implicating VfGlu1 in the disease process. Agrobacterium-mediated transformation affords an efficient technique for the disruption of genes associated with disease symptom development in the complex V. fungicola-A. bisporus interaction.

Agaricus↗

Great expectations: "I'm losing 25% of my weight no matter what you say".

This study investigated whether informing obese individuals that they would lose only modest amounts of weight would lead them to adopt more realistic weight loss expectations. At a screening interview, 53 obese women reported that they expected to lose the equivalent of 28% of their initial weight during 1 year of treatment with the medication sibutramine. Prior to beginning treatment, participants were informed, both verbally and in writing, that they could expect to lose 5% to 15% of initial weight, the loss typically induced by current behavioral and pharmacologic approaches. This information, however, had little impact on their weight loss expectations when assessed on subsequent occasions. Results are discussed in terms of the origins, clinical significance, and potential malleability of obese individuals' weight loss expectations.

Adult↗

Primary care physicians' attitudes about obesity and its treatment.

OBJECTIVE: This study was designed to assess physicians' attitudes toward obese patients and the causes and treatment of obesity. RESEARCH METHODS AND PROCEDURES: A questionnaire assessed attitudes in 2 geographically representative national random samples of 5000 primary care physicians. In one sample (N = 2500), obesity was defined as a BMI of 30 to 40 kg/m(2), and in the other (N = 2500), obesity was defined as a BMI > 40. RESULTS: Six hundred twenty physicians responded. They rated physical inactivity as significantly more important than any other cause of obesity (p < 0.0009). Two other behavioral factors-overeating and a high-fat diet-received the next highest mean ratings. More than 50% of physicians viewed obese patients as awkward, unattractive, ugly, and noncompliant. The treatment of obesity was rated as significantly less effective (p < 0.001) than therapies for 9 of 10 chronic conditions. Most respondents (75%), however, agreed with the consensus recommendations that a 10% reduction in weight is sufficient to improve obesity-related health complications and viewed a 14% weight loss (i.e., 78 +/- 5 kg from an initial weight of 91 kg) as an acceptable treatment outcome. More than one-half (54%) would spend more time working on weight management issues if their time was reimbursed appropriately. DISCUSSION: Primary care physicians view obesity as largely a behavioral problem and share our broader society's negative stereotypes about the personal attributes of obese persons. Practitioners are realistic about treatment outcomes but view obesity treatment as less effective than treatment of most other chronic conditions.

Adult↗

A novel volumetric magnetic resonance imaging paradigm to study upper airway anatomy.

STUDY OBJECTIVES: We utilized novel three-dimensional volumetric analysis techniques with magnetic resonance imaging (MRI) to study the upper airway and surrounding soft-tissue structures. These MRI techniques allowed us to objectively quantify the volume of the tongue, soft palate, parapharyngeal fat pads, and lateral pharyngeal walls. DESIGN: We first validated our volumetric imaging techniques on a phantom and then demonstrated that our results were reliable and reproducible in normal subjects who did not lose weight. Finally, we studied 12 obese, nonapneic women during wakefulness before and after weight loss. We hypothesized that our novel magnetic-resonance computer-reconstruction techniques would allow us to detect small reductions in the volume of the tongue, soft palate, lateral pharyngeal walls, and parapharyngeal fat pads and increases in the volume of the upper airway with weight loss. SETTING: University medical center. PARTICIPANTS: Normal controls and 12 obese nonapneic women. INTERVENTIONS: Weight loss. MEASUREMENTS AND RESULTS: Following a mean 17.1+/-8.62 kg (17.3%) reduction in weight, upper airway volume increased (p = 0.06) in both the retropalatal and retroglossal regions. This increase in upper airway volume was mediated by significant reductions in the volume of the lateral pharyngeal wall (p = 0.0001) and parapharyngeal fat pads (p = 0.001). However, the volume of the tongue (p = 0.35) and soft palate (p = 0.39) were not reduced significantly with weight loss. CONCLUSIONS: These data indicate that volumetric MRI is a powerful tool to study anatomic changes in the upper airway and surrounding soft-tissue structures and is sensitive enough to detect changes in these structures.

Adipose Tissue↗

Obesity: responding to the global epidemic.

Obesity has reached epidemic proportions in the United States and other developed nations. In the United States, 27% of adults are obese and an additional 34% are overweight. Research in the past decade has shown that genetic influences clearly predispose some individuals to obesity. The marked increase in prevalence, however, appears to be attributable to a toxic environment that implicitly discourages physical activity while explicitly encouraging the consumption of supersized portions of high-fat, high-sugar foods. Management of the obesity epidemic will require a two-pronged approach. First, better treatments, including behavioral, pharmacologic, and surgical interventions, are needed for individuals who are already obese. The second and potentially more promising approach is to prevent the development of obesity by tackling the toxic environment. This will require bold public policy initiatives such as regulating food advertising directed at children. The authors call not for the adoption of a specific policy initiative, but instead propose that policy research, based on viewing obesity as a public health problem, become a central focus of research.

Algorithms↗