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Effect of low-calorie diets on plasma retinol-binding protein concentrations in overweight women.
The concentrations of total protein, albumin and retinol-binding protein, a major transport protein for vitamin A, are significantly decreased by protein-calorie malnutrition. weight-loss diets, sometimes involving severe energy deficits over prolonged periods of time, are common in the United States. The effect, if any, of prolonged low calorie weight-loss diets with normal intakes of protein on albumin, total protein and retinol-binding protein concentrations (and potentially on vitamin A metabolism) had not been extensively studied. We measured total protein, albumin, apo + holo retinol-binding protein and holo-free- and holo-transthyretin-bound retinol-binding protein concentrations during the course of a nutritionally adequate weight-loss diet (50% calorie restriction). We found that this type of dieting did not affect total protein, albumin or apo + holo, holo-free or holo-transthretin-bound retinol-binding protein concentrations significantly. This suggests that protein intake is more critical than caloric intake for retinol-binding protein status.
Malignancy risk prediction for primary jejunum-ileal tumors.
This work is aimed at identifying factors associated with primary jejunum-ileal tumors malignancy, defining a prediction model with sensitivity, specificity and accuracy to distinguish malign from benign neoplasms. These tumors are rare, have highly unspecific presentation and, frequently, are diagnosed late. We reviewed the charts of 42 patients with primary jejunum-ileal tumors treated in the Department of General Surgery of Rio de Janeiro State University Hospital, Rio de Janeiro, RJ, Brazil, from 1969 to 1998. We performed bivariate analyses, based on chi 2 test, searching associations between tumors malignancy and demographic and clinical variables. Then logistic regression was employed to consider the independent effect of variables previously identified on malignancy risk. The malign tumors included 11 adenocarcinomas, 7 leiomyosarcomas, 5 carcinoids and 4 lymphomas; the benign tumors included 10 leiomyomas, 2 hamartomas, and single cases of adenoma, multiple neurilemoma and choristoma. The bivariate analyses indicated the association between malignancy and palpable abdominal mass (P = 0.003), period from signs and symptoms onset to diagnosis (P = 0.016), anemia (P = 0.020), anorexia (P = 0.003), abdominal pain (P = 0.031), weight loss (P = 0.001), nausea and vomit (P = 0.094), and intestinal obstruction (P = 0.066); no association with patients demographic characteristics were found. In the final logistic regression model, weight loss, anemia and intestinal obstruction were statistically associated with the dependent variable of interest. Based only on three variables--weight loss, anemia and intestinal obstruction--the model defined was able to predict primary jejunum-ileal tumors malignancy with sensitivity of 85.2%, specificity of 80.0%, and accuracy of 83.3%.
Laparoscopic gastric bypass as a reoperative bariatric surgery for failed open restrictive procedures.
An estimated 2% of men and 6% of women in the United States are morbidly obese. These patients have a mortality rate that is six to twelve times greater than their normal-weight peers. In these extreme cases of overweight, only surgical intervention can produce substantial and sustained weight loss. However, up to 20% of these patients will require reoperation for failure to achieve or maintain an adequate weight loss. Reoperative bariatric surgery can be challenging and has traditionally been performed as an open procedure. We present seven female patients who underwent a laparoscopic Roux-en-Y gastric bypass after failing to achieve their weight-loss goals with prior open restrictive procedures. Their average BMI before surgical revision was 42.2 kg/m2. Mean operative time was 4 h 20 min, and length of hospital stay was 4.1 days. There were three complications in two patients and no deaths. Our initial experience suggests that laparoscopic gastric bypass is a safe and feasible reoperative bariatric procedure. Confirmation awaits a larger series of patients with follow-up data.
Body weight loss during lactation and its influence on weaning-to-service interval and ovulation rate in Landrace and Yorkshire sows in the tropical environment of Thailand.
The aim of this study was to investigate the ovulation rate and the weaning-to-service interval (WSI) of sows in relation to their body weight loss during lactation in tropical climatic conditions. Effect of lactation length (LL), number of total born piglets, number of live born piglets, litter birth weight, average piglet birth weight, number of pigs weaned, litter weaning weight and average pig weaned weight on sow weight loss during lactation were also studied. This study was conducted in two commercial purebred sow herds (A, B) in the central part of Thailand from August to December 1997. The herds had both Landrace (L) and Yorkshire (Y) sows. The 123 sows (55 L and 68 Y) in herd A and 153 sows (95 L and 58 Y) in herd B, parity 1-4, were weighed within 4 days after farrowing and at weaning. Lactation length, litter size at birth and at weaning, litter weight at birth and at weaning, and WSI were recorded for each of these sows. In herd A, 52 sows (20 L and 32 Y) were examined once by laparoscopy between days 8 and 14 after AI-service. These sows had farrowed at least seven piglets in the previous parturition. The numbers of corpora lutea (CL) in both ovaries were counted, and were assumed to equal the ovulation rate. L-sows had significantly (P < 0.05) higher relative weight loss during lactation (RWL) than Y-sows. The RWL increased by 0.7% for each extra pig weaned. When LL increased by 1 day, within the interval of 17-34 days, RWL decreased by 0.6%. Sows with a high weight loss had significantly (P < 0.05) longer WSI than sows with medium or low weight loss. weight loss had a significant (P < 0.05) effect on WSI in parity 1 and 2 sows. Y-sows had more CL than L-sows (15.7 versus 14.0) (P < 0.05). RWL, parity and regression on lactation length had no significant effect on number of CL. In conclusion, sows with higher number of pigs weaned lose more weight. Under the restricted feeding regime applied, high weight loss during lactation prolongs WSI in parity 1 and 2 sows, but has no influence on the ovulation rate at first oestrus after weaning. The ovulation rate is higher in Yorkshire than in Landrace sows. The ovulation rate is independent of parity.
Tumor necrosis factor-alpha serum levels, weight loss and tissue oxygenation in chronic obstructive pulmonary disease.
weight loss has been recognized as a feature of advanced emphysema and a factor of poor prognosis, but its mechanisms remain obscure. Studies have demonstrated high serum concentrations of TNF-a (cachexin) in chronic obstructive pulmonary disease (COPD) patients with emphysema. Pink puffers (PP) COPD patients have worse tissue oxygenation when compared with blue bloaters (BB) COPD patients. Consequently, PP patients would become cachectic, whereas BB patients with better tissue oxygenation would not. The aim of this study is to test the hypothesis that malnutrition in emphysema is a cytokine-mediated marker of chronic progressive tissue hypoxia. Thirty male COPD patients, without clinical or laboratory evidence of infection and severe air way obstruction (FEV1 < 1.5 l) were allocated: 16 as pink puffers (PP) and 14 as blue bloaters (BB). Lung function measurements included FEV1, FVC, RV, TLC, DLCO and arterial blood gases on room air. TNF-a serum levels were measured by immunoenzymic method (ELISA). Tissue oxygenation was assessed from oxygen delivery (DO2), PvO2 and oxygen extraction ratio (O2ER) obtained after right heart catheterization with Swan Ganz catheter. PP patients demonstrated lower DLCO and higher TLC, FRC and PaO2 from BB. We found that oxygen delivery was better in our BB than in PP patients (CI 2.9 +/- 0.2 vs 2.5 +/- 0.4 l/min/m2--P < 0.01, DO2 16.1 +/- 2.1 vs 13.1 +/- 0.2 ml/min/kg--P < 0.001) and the same was found for tissue oxygenation (PvO2 34.6 +/- 2.9 vs 31.2 +/- 3.8 mmHg--P < 0.01, O2ER 0.27 +/- 0.02 vs 0.34 +/- 0.06%--P < 0.001). The TNF-a values were higher in PP (31.3 +/- 26 pg/ml vs 15.2 +/- 9.9 pg/ml--P < 0.05) and their percent fat-free mass (%FFM) was 49.6 +/- 11.5 vs 42 +/- 8%--P < 0.001. We found that COPD patients with lower DO2 had increased TNF-a levels; but the correlations between TNF-a serum levels and PvO2 or O2ER were not statistically significant. TNF-a levels were elevated in PP patients with tissue hypoxia and may be a factor contributing to the weight loss of these patients.
Change in beta(1)-adrenergic receptor protein concentration in adipose tissue correlates with diet-induced weight loss.
The aim of the present study was to examine gene expression and protein concentrations of beta(1)- and beta(2)-adrenergic receptors in subcutaneous adipose tissue in obese subjects in response to weight loss. Eighteen obese subjects were studied during diet-induced weight loss. beta-Adrenergic receptor mRNA levels were quantified by reverse transcription-PCR-HPLC. beta-Adrenergic receptor protein concentrations were measured by Western blotting using fluorescence laser scanning for detection. Subjects lost 12.8+/-0.8 kg (mean+/-S.E.M.) during diet treatment. There was a 34% decrease in the beta(1)-adrenergic receptor mRNA level (0.92+/-0.09 compared with 0.61+/-0.06 amol/mug of DNA; P<0.002). beta(2)-Adrenergic receptor mRNA did not decrease significantly. beta(2)-Adrenergic receptor protein concentration decreased 37% (25.5+/-7.1 compared with 16.0+/-5.6 arbitrary units/ng of DNA; P=0.008), whereas beta(1)-adrenergic receptor protein concentration did not decrease significantly. The degree of weight loss was correlated with the concentration of beta(1)-adrenergic receptor protein (r=0.65, P<0.003) and changes in receptor protein concentration (r=0.50, P=0.035) during the very-low-calorie diet. In conclusion, the present study demonstrates a relationship between beta(1)-adrenergic receptor protein concentration in adipose tissue and the degree of weight loss. This relationship is not directly related to energy expenditure and deserves further investigation.
Do patients with nonmetastatic non-small cell lung cancer demonstrate altered resting energy expenditure?
BACKGROUND: The cancer cachexia syndrome occurs in patients with non-small cell lung cancer (NSCLC) and includes elevated resting energy expenditure (REE). This increase in REE leads to weight loss, which in turn confers a poor prognosis. This study was undertaken to determine whether the cancer cachexia syndrome occurs in patients with nonmetastatic NSCLC. METHODS: In this case-control study, 18 patients with nonmetastatic NSCLC (stages IA to IIIB) were matched to healthy controls on age (+/- 5 years), gender, and body mass index (+/- 3 kg/m2). Only 4 cancer patients had experienced > 5% weight loss. Cancer patients and controls were compared on the basis of: (1) unadjusted REE, as measured by indirect calorimetry; (2) REE adjusted for lean body mass, as measured by dual x-ray absorptiometry; (3) REE adjusted for body cell mass, as measured by potassium-40 measurement; and (4) REE adjusted for total body water, as measured by tritiated water dilution. RESULTS: We observed no significant difference in unadjusted REE or in REE adjusted for total body water. However, with separate adjustments for lean body mass and body cell mass, cancer patients manifested an increase in REE: mean difference +/- standard error of the mean: 140+/-35 kcal/day (p = 0.001) and 173+/-65 kcal/day (p = 0.032), respectively. Further adjustment for weight loss yielded similarly significant results. CONCLUSIONS: These results suggest that the cancer cachexia syndrome occurs in patients with nonmetastatic NSCLC and raise the question of whether clinical trials that target cancer cachexia should be initiated before weight loss.
Using self-efficacy to predict weight loss among young adults.
Many healthcare professionals support the idea that weight control and healthy eating should be emphasized early in a person's life to prevent obesity during middle and older adulthood. Unfortunately, although many weight loss programs are available to consumers, few are successful. Recently, constructs of behavioral theories have been integrated into weight loss programs and used to promote changes in health behaviors. In this study, methods used to increase self-efficacy for weight loss were incorporated into a 12-week program designed for weight loss promotion in young adults. Results found that as self-efficacy improved, eating habits improved and weight loss was greater. This study supports the hypothesis that using behavioral techniques to improve self-efficacy can be effective in weight loss promotion and can produce positive outcomes.
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