Substitution of high monounsaturated fatty acid avocado for mixed dietary fats during an energy-restricted diet: effects on weight loss, serum lipids, fibrinogen, and vascular function.

OBJECTIVE: First, we wanted to dispel the myth that avocados are fattening and therefore should be avoided in energy-restricted diets. Second, we examined the effects of avocados, a rich source of monounsaturated fatty acids, as part of an energy-restricted diet on weight loss, serum lipids, fibrinogen, and vascular function in overweight and obese subjects. METHODS: Sixty-one free-living volunteers (13 men and 48 women), with body mass index of 32 +/- 3.9 kg/m(2) (mean +/- standard deviation) participated in this randomized, controlled, parallel study. Subjects were paired and randomly assigned to one of two groups. The experimental group consumed 200 g/d of avocado (30.6 g of fat), which substituted for 30 g of other mixed dietary fats such as margarine or oil, and the control group excluded avocado from their energy-restricted diet for 6 wk. Seven-day isoenergetic menus were planned according to mean energy requirements of both sexes to provide total energy intakes consisting of 30% fat, 55% carbohydrates, and 15% protein. Anthropometric measurements, physical activity, blood pressure, and arterial compliance were measured with standard methods at the beginning and end of the intervention. Fasting blood samples were drawn at the beginning and end of the intervention. RESULTS: Fifty-five subjects completed the study. The compliance rate to avocado intake in the experimental group was 94.6%. The percentage of plasma oleic acid increased significantly with the consumption of avocado in the experimental group, whereas a decrease was seen in the percentage of myristic acid from baseline to the end of the intervention in both groups but was significant only in the experimental group. Anthropometric measurements (body mass, body mass index, and percentage of body fat) decreased significantly in both groups during the study (P < 0.001), and the change was similar in both groups. Serum lipid concentrations (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triacylglycerols), fibrinogen, blood pressure, and arterial compliance did not change significantly within or between groups. CONCLUSION: The consumption of 200 g/d of avocado within an energy-restricted diet does not compromise weight loss when substituted for 30 g of mixed dietary fat. Serum lipid concentrations, plasma fibrinogen, arterial compliance, and systolic and diastolic blood pressures were not affected by weight loss or avocado intake.

Nutritional behavior as a predictor of early success after vertical gastroplasty.

BACKGROUND: Patients' nutritional habits are seldom taken in account in planning surgery for clinically severe obesity. Our proposed hypothesis is that the patient's nutritional behavior may influence the outcome of bariatric surgery. METHODS: The impact of nutritional behavior on the postoperative weight-loss was evaluated before and after bariatric surgery. A 6-month prospective consecutive case study was carried out on patients undergoing a Silastic ring vertical gastroplasty (SRVG). Patients were interviewed and examined before and at 1, 3 and 6 months after surgery. Demographic and clinical data were collected from the patients' medical charts. Nutritional data collected from a self-filled questionnaire included information on hunger and satiety perception, nutritional behavior (intake, eating habits and maximum consistency of consumed food) and concomitant symptoms. RESULTS: The sample included 69 patients: 56 were women (81%); average age was 32 years (range 18 50). Average preoperative BMI was 43.4 +/- 5.3 kg/m2 (range 35-58). 6 months after surgery, BMI was 30.3 +/- 3.8 kg/m2 (range 21-42). weight loss forecast models showed a statistically significant role of factors related to: anthropometrical preoperative data, hunger perception, prevalence of oral mucosal sore, and nutritional behavior. CONCLUSION: The short nutrition outcomes after gastric restrictive surgery were looked at, with their impact on weight-loss success. The Eating Status concept should be part of a systematic profiling of morbidly obese patients for preoperative nutritional behavior and postoperative nutritional education, to achieve the best comprehensive treatment in regard to weight loss and quality of life.

Gelatin Blending Improves the Performance of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) Films for Biomedical Application.

To improve the performance of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), gelatin was blended with PHBHHx at different ratios. With increasing gelatin content, the weight loss of gelatin/PHBHHx blend in simulated body fluid at 37 degrees C was accelerated. After 2 months, there was about 15% weight loss in PHBHHx blending with 30% gelatin. Scanning electron microscopy and X-ray diffraction results showed that gelatin blending increased the surface porosity and decreased the crystallinity, which may be responsible for the acceleration of the weight loss. Second harmonic generation results indicated that 10% gelatin blending had less disruption to PHBHHx spatial structure, resulting in better tensile mechanical properties. At the same time, increased surface porosity and decreased crystallinity caused by gelatin incorporation may be beneficial for cell growth compared with pure PHBHHx. All these indicated that gelatin incorporation may improve the performances of PHBHHx to meet the need of different situations during medical implantation.

Laparoscopic Roux-en-Y gastric bypass: minimally invasive bariatric surgery for the superobese in the community hospital setting.

Roux-en-Y gastric bypass (RYGB) operation has become a popular choice for weight-reduction surgery. We report an outcome analysis of our early results with laparoscopic Roux-en-Y gastric bypass for superobese (BMI >50) patients. Between January 2000 and October 2001, we operated on 71 superobese patients. The mean body mass index (BMI) of patients at time of surgery was 57 kg/m2. The prospectively collected data included patient demographics, comorbidities, operative times, postoperative weight loss, and complications. Conversion to open gastric bypass was required in one patient. The overall complication rate was 10 per cent. Preoperative comorbidities were resolved or improved in 93 per cent of patients at 1-year postoperative. Average operative time and length of hospital stay were 196 minutes and 2.3 days, respectively. Mean percentage excess weight loss at 3, 6, 9, and 12 months was 27 per cent, 39 per cent, 49 per cent, and 55 per cent, respectively. Mean BMI decreased to 36 kg/m2 over a 12-month period. Laparoscopic Roux-en-Y gastric bypass surgery for superobese patients as performed in the community hospital setting can be both safe and effective with respect to overall postoperative course, early weight loss, and reduction of comorbidity.

Effects of different weight loss protocols on serum leptin levels in obese females.

We comparatively investigated the effects of different weight loss protocols on leptin levels in obese females with the aim of addressing the leptin resistance which have been determined to be an aggravating factor in obesity. Twenty-four obese females enrolled to one of the three 12 week weight loss protocols: Orlistat ( Xenical )-induced weight loss (OWL, n=8), exercise-induced weight loss (EWL, n=8) and Orlistat ( Xenical ) plus exercise-induced weight loss (OEWL, n=8). Serum leptin levels were measured in duplicate by radioimmunoassay. There were significant reductions in body weight and fat mass after the 12 week period in all groups: -11.4+/-0.5 kg (P=0.01) and -9.8+/-0.5 kg (OEWL), -8.3+/-0.8 kg (P=0.01) and -5.7+/-0.9 kg (OWL), -8.9+/-1.2 kg (P=0.01) and -7.4+/-1.2 kg (EWL), respectively. Serum leptin levels were also decreased markedly in all groups: -59.2% (OEWL, P=0.01), -37.8% (OWL, P=0.01) and -48.6% (EWL, P=0.01). In addition, there were marked decreases in leptin levels for each kilogram of fat mass after the 12 week period: -48.2+/-7.2% (OEWL P=0.01), -27.8+/-4.8% (OWL, P=0.01) and -39.3+/-4.3% (EWL, P=0.01). Decreases in serum leptin levels expressed per kilogram of fat mass were significantly higher in OEWL group compared to OWL (P= 0.03). Consequently, in obesity treatment, an exercise training program in adjunct to pharmacotherapy provides higher amount of weight reduction and fat mass loss, and importantly seem to have further beneficial effects on leptin resistance, as indicated by decreases in leptin levels expressed per kilogram of fat mass.

Sustained weight loss in obese subjects has benefits that are independent of attained weight.

OBJECTIVE: To explore the hypothesis that sustained weight loss in severely obese patients may have benefits that are independent of their attained BMI. RESEARCH METHODS AND PROCEDURES: We conducted a comparison of two weight-stable groups with BMI in the 30 to 35 kg/m(2) range. Subjects (n = 79) were selected obese patients 3 years after laparoscopic adjustable gastric band surgery, and controls (n = 79) were obese patients seeking weight loss therapy. Subjects were selected in a de-identified manner from our database to best match the control group. A range of clinical, biochemical, and questionnaire measures were obtained to assess obesity-related health status RESULTS: Subjects maintained a mean weight loss of 32.8 +/- 18 kg after surgery. The weight loss subjects had significantly lower fasting plasma glucose, insulin, and triglyceride concentrations, along with higher high-density lipoprotein-cholesterol levels and better indirect measures of insulin sensitivity when compared with controls (p < 0.05 for all). In addition, aminotransferase levels, neutrophil counts, and globulin levels were also significantly lower in weight loss subjects. All differences in laboratory variables remained significant after controlling for BMI. The subjects also reported better health-related quality of life, fewer symptoms of depression, and greater satisfaction with their appearance than controls. DISCUSSION: These findings suggest that the post-weight loss state conveys benefits that are greater than predicted by the attained BMI. These findings may have important implications regarding the expectations of weight loss therapy, and mechanisms for this effect should be carefully sought.

Interest of pronostic score for optimal clinical management of obese patients.

OBJECTIVE: The aim of this retrospective study was to identify key factors favoring weight regain. METHODS: Therefore, prognostic factors for weight loss and regain have been retrieved and identified among 186 obese patients (40 +/- 2 y and 34 +/- 0.3 kg/m(2)) through the use of a simple questionnaire which considered psychological issues such as depression, anxiety and the patient's individual capacity to follow a diet. All patients have been prescribed a low-calorie diet (1200 kcal/day) being either balanced, food-combining or low-CHO. Follow-up averaged 6.4 +/- 0.3 months of which weight loss accounted for 4.4 +/- 0.1 months. RESULTS: weight loss was similar in all 3 groups and averaged 6.0 +/- 0.2 kg. The final weight loss and weight regain results have been identical for the 3 groups. A high/bad prognostic score rating is associated with weight regain (P<0.02). Weight regain is significantly influenced by the initial weight loss speed (P<0.0001). CONCLUSIONS: The proposed prognostic score is likely to be helpful for clinicians better to profile the therapeutic approach to individualized obesity management and follow-up. Diet composition does not influence either weight loss or weight regain.

Central administration of transforming growth factor-alpha and neuregulin-1 suppress active behaviors and cause weight loss in hamsters.

Transforming growth factor-alpha (TGF-alpha) is a candidate output signal of the hypothalamic circadian pacemaker. TGF-alpha is expressed in the suprachiasmatic nucleus (SCN) of rats, hamsters, and rhesus macaques [A. Kramer, F.C. Yang, P. Snodgrass, X. Li, T.E. Scammell, F.C. Davis and C.J. Weitz, Regulation of daily locomotor activity and sleep by hypothalamic EGF receptor signaling, Science, 294 (2001) 2511-5., X. Li, N. Sankrithi and F.C. Davis, Transforming growth factor-alpha is expressed in astrocytes of the suprachiasmatic nucleus in hamster: role of glial cells in circadian clocks, Neuroreport, 13 (2002) 2143-7., Y.J. Ma, M.E. Costa and S.R. Ojeda, Developmental expression of the genes encoding transforming growth factor alpha and its receptor in the hypothalamus of female rhesus macaques, Neuroendocrinology, 60 (1994) 346-59., Y.J. Ma, M.P. Junier, M.E. Costa and S.R. Ojeda, Transforming growth factor-alpha gene expression in the hypothalamus is developmentally regulated and linked to sexual maturation, Neuron, 9 (1992) 657-70.]. TGF-alpha reversibly inhibits wheel-running activity during long-term infusions into the third ventricle of hamsters (2 weeks, intracerebroventricular or ICV) [A. Kramer, F.C. Yang, P. Snodgrass, X. Li, T.E. Scammell, F.C. Davis and C.J. Weitz, Regulation of daily locomotor activity and sleep by hypothalamic EGF receptor signaling, Science, 294 (2001) 2511-5.], and this effect appears to be mediated by the epidermal growth factor receptor (EGFR or ErbB-1) [A. Kramer, F.C. Yang, P. Snodgrass, X. Li, T.E. Scammell, F.C. Davis and C.J. Weitz, Regulation of daily locomotor activity and sleep by hypothalamic EGF receptor signaling, Science, 294 (2001) 2511-5.]. Here, we demonstrate that this inhibitory effect is not restricted to wheel-running behavior or to mediation by the EGFR. Using direct observation, we found the effects of long-term TGF-alpha infusion (ICV, 12 mul/day, 3.3 muM) to be more general than previously reported. Other active behaviors such as grooming and feeding were reversibly inhibited and hamsters showed dramatic weight loss as a result of reduced feeding (34% of body weight over 19 days). TGF-alpha did not disrupt a non-behavioral rhythm, the rhythm in pineal melatonin. Wheel-running activity was also inhibited by another epidermal growth factor-like (EGF-like) peptide, neuregulin (NRG-1), that binds to different ErbB receptors. Like TGF-alpha, NRG-1 caused a significant weight loss. We also show that an acute injection of TGF-alpha inhibits activity (ICV, 5 mul, 3.3 muM over 2 min), with inhibition and recovery occurring over a few hours. Although the results are consistent with the proposed [A. Kramer, F.C. Yang, P. Snodgrass, X. Li, T.E. Scammell, F.C. Davis and C.J. Weitz, Regulation of daily locomotor activity and sleep by hypothalamic EGF receptor signaling, Science, 294 (2001) 2511-5.] role for EGF-like peptides in the daily regulation of activity, the actions of these peptides might also contribute to the behavioral etiology of diseases in which EGF-like peptides are expressed.