Weight loss
Incidence of dehydration and hypernatremia in exclusively breast-fed infants.

Manganaro R, Mami C, Marrone T, Marseglia L, Gemelli M.

Neonatology Unit of the University of Messina, 98100 Messina, Italy.

OBJECTIVES: To verify in exclusively breast-fed, term infants the incidence of hypernatremic dehydration and identify possible maternal and/or infant factors that interfere with successful breast-feeding. STUDY DESIGN: We prospectively included all healthy breast-fed neonates referred to our Neonatology Unit between October 1999 and March 2000. All neonates with a weight loss > or = 10% of birth weight had a breast-feeding test and a determination of serum sodium, urea, and base excess. Student t test and chi-square test were used for statistical analysis of the data. RESULTS: Of 686 neonates, 53 (7.7%) had a weight loss > or = 10% of the birth weight, and 19 also had hypernatremia. These 53 neonates had a significantly higher incidence of caesarean delivery and lower maternal education than neonates with a weight loss < 10%. CONCLUSION: Our prospective study demonstrates that a weight loss > or = 10% during the first days of life is frequent. Daily weight evaluation, careful breast-feeding assessment, and early routine postpartum follow-up are effective methods to prevent hypernatremic dehydration and promote breast-feeding.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11713445&dopt=Abstract weight loss



Weight loss
Increase in skeletal muscle fatty acid binding protein (FABPC) content is directly related to weight loss and to changes in fat oxidation following a very low calorie diet.

Blaak EE, Glatz JF, Saris WH.

Department of Human Biology, Nutrition Research Centre, Maastricht University, Maastricht, The Netherlands. E.Blaak HB.Unimaas.nl

AIMS/HYPOTHESIS: There is increasing evidence that intracellular fatty acid binding proteins (FABPc's; 15 kD) function as vehicles of cytosolic fatty acid transport. We studied skeletal muscle cytosolic FABPc, and enzymes reflecting beta-oxidation and oxidative capacity (3-hydroxyacyl-CoA dehydrogenase, HAD, and citrate synthase, CS) in relation to weight loss and changes in substrate utilisation in a group of 35 obese women and obese men with Type II (non-insulin-dependent) diabetes mellitus (women = 27, men = 8). METHODS: Muscle biopsies (vastus lateralis), and measurements of body composition, resting energy expenditure and respiratory exchange ratio were taken before and after dietary intervention (by means of a very low calorie diet). RESULTS: Muscle FABPc tended to increase after diet (178 +/- 13 vs 204 +/- 12 mg x gww(-1), p = 0.06), whereas there were no changes in CS (10.5 +/- 0.7 vs 11.1 +/- 0.6 U x gww(-1)) and HAD (11.2 +/- 0.7 vs 11.7 +/- 0.6 U x gww(-1)). There was a positive relation between the increase in FABPc as result of diet and the amount of weight lost (p < 0.01; adjusted R2, 15.4 %), even when adjusted for mean body weight, and changes in CS and in HAD by partial regression analysis. Interestingly, the increase in FABPc was positively related to increases in resting fat oxidation (adjusted R2, 24 %), even when adjusted for mean resting fat oxidation, and changes in CS and in HAD. CONCLUSION/INTERPRETATION: In conclusion, the ability to increase muscle FABPc could be directly related to weight loss and to changes in fat oxidation following dietary intervention in obesity and Type II (non-insulin-dependent) diabetes mellitus.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11719832&dopt=Abstract weight loss



Weight loss
[Non-small cell bronchogenic carcinoma in advanced stages: prognostic value of weight loss and clinical implications]

[Article in Spanish]

Gullon J, Fernandez R, Rubinos G, Medina A, Suarez I, Gonzalez I.

Seccion de Neumologia, Hospital Universitario de Canarias, La Laguna, Santa Cruz de Tenerife, Spain.

This study of advanced-stage non-small cell bronchogenic carcinoma aimed 1) to identify prognostic factors collected at the moment of diagnosis, 2) to determine whether weight loss is a useful parameter to screen for subjects who will receive greater benefit from anticancer therapy.Patients and methods. Eighty-one patients were enrolled after diagnosis of stage III-B and IV non-small cell bronchogenic carcinoma and levels of activity < 2 according to Eastern Co-operative Oncology Group classification. The variables studied were age, sex, smoking history, associated disease, clinical data (weight loss, dyspnea, superior vena cava syndrome), laboratory parameters [hemoglobin, serum albumin, total lymphocytes, serum lactate dehydrogenase (LDH), calcium and liver enzymes], tumor-node-metastasis (TNM) staging, histologic type, activity, treatment received and survival in weeks.The results were analyzed in two groups: 1) the general group consisting of results for all patients, and 2) the no-weight-loss group consisting of results for those whose weight had been stable.Student t, chi-squared, Kaplan Meier, log-rank and Cox's regression model were used to analyze data and survival.Results: Mean survival was 29 weeks (21-37). Survival was significantly related to weight loss, total lymphocytes, serum LDH, TNM and activity level in the general group. Only two factors continued to have prognostic value in the multivariate study: weight loss (OR: 1.48 (1.14-1.92), p = 0.002) and TNM (OR: 0.72 (0.54-0.96), p = 0.02).Among the patients with no weight loss, treatment received and TNM were significantly related to survival in univariable analysis and in Cox's regression model.Conclusions: In our experience with advanced lung cancer subjected to anticancer therapy, the presence of weight loss is the variable with the greatest prognostic value, such that it may be useful to consider it routinely, along with activity level, to try to identify patients who will receive the most benefit from cytostatic treatment.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11734136&dopt=Abstract weight loss



Weight loss
Biexponential model for predicting weight loss after gastric surgery for obesity.

Livingston EH, Sebastian JL, Huerta S, Yip I, Heber D.

Department of Surgery, VA Greater Los Angeles Health Care System, Los Angeles, California 90073, USA. elivings ucla.edu

BACKGROUND: Following gastric restrictive surgery, morbidly obese patients rarely achieve their ideal body weight defined by Metropolitan Life tables. The final body weight will depend on the initial body composition because there will be greater weight loss from fat than lean body mass. The purpose of this study was to develop a mathematical model that accurately estimates the rate and extent of weight loss following gastric bypass surgery. METHODS: Patients underwent gastric bypass followed by intensive medical therapy and serial bioelectrical impedance analysis (BIA) body composition measurements. Differential equations were derived to model weight loss. RESULTS: Weight loss in the fat and lean body compartments followed monoexponential decay kinetics with differing rate constants. Total body weight loss (W(T)) at time t was W(T) = k(f)(k(f) - k(l)) (W(f(o))e(-k(f)t) + W(l(o))e(-k(l)t)), where W(fo) and W(lo) are the initial fat and lean body masses determined by BIA and k(f) and k(l) are the rate constants for the fat and lean compartments, respectively. Following surgically induced weight loss, k(f) = 7.61 +/- 1.27 x 10(-2), and k(l) = -0.93 +/- 0.13 x 10(-2), with the ratio of residual sum of the squares to the total sum of the squares of 98.8%. CONCLUSION: Accurate prediction of weight loss depends on the initial fat and lean compartment mass since each of these loses weight at a different rate and to a different extent. When these effects are accounted for, the total body weight loss can be accurately predicted for any given time following surgery.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11735279&dopt=Abstract weight loss



Weight loss
Physicochemical properties and structural changes in vegetative tissues as affected by a direct current electrical field.

Zvitov R, Nussinovitch A.

Institute of Biochemistry, Food Science and Nutrition, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.

Cylindrical pieces of potato, sweet potato, kohlrabi, radish, and pear were interposed between a pair of electrodes, and a direct current was applied. A special custom-made apparatus enabled the use of differently shaped electrodes. The electrical field was applied for 1 min at 40 V/cm and caused a reduction in specimen weight by a minimal value of 2.7% of initial weight in sweet potato to a maximum 38.4% in pear. The affected area of the tissue resembled the shape of the electrode. Pores were produced in the tissue (from the anode side), possibly promoting slow release of minerals and other cell components from the contracted specimens. From the cathode side, cell "sealing" could be observed. Weight loss was dependent on the mechanical properties of the nontreated vegetative tissue specimens. After confirmation that all samples pass through induced electrical shrinkage, further work, executed only on potato, demonstrated that after electrical treatment the samples were less brown (higher L values). In addition, a dependence of weight loss on current intensity, electrode diameter, and surface ratio between the electrode and specimen was shown. The reduction in weight loss could be useful for initial drying of vegetative materials. Indirect proof of a decrease in enzyme activity as a result of electrical field application could be beneficial in replacing traditional methods for browning prevention.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11735447&dopt=Abstract weight loss



Weight loss
The proportion of CD45RA(+)CD62L(+) (quiescent-phenotype) T cells within the CD8(+) subset increases in advanced weight loss in the protein- or energy-deficient weanling mouse.

ten Bruggencate SJ, Hillyer LM, Woodward BD.

Department of Human Biology and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.

Male and female C57BL/6J mice, initially 19 d old, had free access to a complete purified diet, were fed this diet in restricted daily quantities, or had free access to a low-protein diet. Three separate studies were conducted with feeding periods of 14, 9 or 6 d (n = 7-8 per dietary group and feeding period; 6 d: restricted intake and age-matched controls only). A zero-time control group (19 d old) was included in each study. Malnourished mice lost approximately 2% of initial body weight daily. Naive-phenotype (quiescent) CD8(+) T cells of the blood, spleen and mesenteric lymph nodes were identified on the basis of surface coexpression of CD45RA and CD62L. Relative to age-matched controls, the percentage of naive-phenotype CD8(+) T cells was high in energy-restricted groups after 9 d and 14 d of weight loss and in the protein-restricted groups after 14 d (P < or = 0.05). No ontogenetic change was apparent (age-matched vs. zero-time control). Other studies have demonstrated depression in cell-mediated immune competence in both malnutrition models within the first week of weight loss. An overabundance of quiescent-phenotype T cells within the involuted CD8(+) compartment may contribute to established immune depression but not to its initiation in weight loss pathologies.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11739878&dopt=Abstract weight loss



Weight loss
Weight loss in rats exposed to repeated acute restraint stress is independent of energy or leptin status.

Harris RB, Mitchell TD, Simpson J, Redmann SM Jr, Youngblood BD, Ryan DH.

Pennington Biomedical Research Center, Baton Rouge, Louisiana 70808, USA. harrisrb arches.uga.edu

Acute release of corticotropin-releasing factor (CRF) during repeated restraint (3-h restraint on each of 3 days) causes temporary hypophagia but chronic suppression of body weight in rats. Here we demonstrated that a second bout of repeated restraint caused additional weight loss, but continuing restraint daily for 10 days did not increase weight loss because the rats adapted to the stress. In these two studies serum leptin, which suppresses the endocrine response to stress, was reduced in restrained rats. Peripheral infusion of leptin before and during restraint did not prevent stress-induced weight loss, although stress-induced corticosterone release was suppressed. Restrained rats were hyperthermic during restraint, but there was no evidence that fever or elevated free interleukin-6 caused the sustained reduction in weight. Restraining food-restricted rats caused a small but significant weight loss. Food-restricted rats fed ad libitum after the end of restraint showed a blunted hyperphagia and slower rate of weight regain than their controls. These results indicate that repeated acute stress induces a chronic change in weight independent of stress-induced hypophagia and may represent a change in homeostasis initiated by repeated acute activation of the central CRF system.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11742826&dopt=Abstract weight loss



Weight loss
The insulin tolerance test in morbidly obese patients undergoing bariatric surgery.

Geloneze B, Tambascia MA, Pareja JC, Repetto EM, Magna LA.

Endocrinology Service, Obesity Surgery Unit, Department of Surgery, University of Campinas, Sao Paulo, Brazil. Bgeloneze aol.com

OBJECTIVE: To assess the effect of massive weight loss in relation to insulin resistance and its correlation to changes in glycemic homeostasis and lipid profile in severely obese patients. RESEARCH METHODS AND PROCEDURES: A prospective clinical intervention study was carried out with 31 morbidly obese women (body mass index: 54.2 +/- 8.8 kg/m(2)) divided into three groups according to their glucose tolerance test: 14 normal, 8 impaired glucose tolerance, and 9 type 2 diabetes. All subjects underwent an insulin tolerance test with intravenous bolus of 0.1 U insulin/kg body weight before silastic ring vertical gastroplasty Roux-en-Y gastric bypass surgery, and again at 2, 4, 6, and 12 months postoperatively. Fasting plasma glucose, hemoglobin A1c, and lipid profile were also evaluated. RESULTS: A reduction of 68 +/- 15% in initial excess body weight was evident within 1 year. Along with weight loss, the following statistically significant changes were found: an increase in the insulin-sensitivity index (Kitt) and a decrease in fasting plasma glucose and hemoglobin A1c, most notably in the type 2 diabetes group. An overall improvement in lipid profile was observed in all three groups. DISCUSSION: Bariatric surgery was an effective therapeutic approach for these obese patients because it reduced both weight and insulin resistance, along with improving metabolic parameters. Significant correlations were found between insulin resistance and metabolic improvements. Weight loss after bariatric surgery induced an improvement in metabolic fitness, related to the reduction in insulin resistance over a range of glucose tolerance statuses from normal to diabetic.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11743060&dopt=Abstract weight loss



Weight loss
Predictors of weight loss during radiation therapy.

Beaver ME, Matheny KE, Roberts DB, Myers JN.

Texas Voice Center, TX, USA.

OBJECTIVE: To define risk factors for weight loss or dehydration during radiation therapy (RT). STUDY DESIGN AND SETTING: Retrospective chart review, academic tertiary care center. RESULTS: The incidence of severe weight loss during RT was 32.7%, the incidence of dehydration was 10.9%, and the rate of prophylactic feeding gastrostomy tube placement was 32%. The patients most likely to suffer severe weight loss included patients with tumor sites of nasopharynx and base of tongue, those treated with chemoradiation, and patients with severe pretreatment weight loss. Prophylactic feeding gastrostomy tube placement before RT significantly reduced the incidence of severe weight loss and hospitalization during RT. CONCLUSION: Severe weight loss and dehydration during RT for head and neck cancer is common. Prophylactic feeding gastrostomy tubes significantly reduce the incidence of severe weight loss and hospitalization for dehydration during RT when placed before onset of RT. Patients at risk for severe weight loss include those with severe pretreatment weight loss, tumors of the nasopharynx and base of tongue, or treatment with chemoradiation.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11743469&dopt=Abstract weight loss