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The present study aimed to assess the utility of a less laborious technique for estimating total body protein (TBPro) in young athletes, using a multicomponent model as the criterion method. A total of 88 (49 boys and 39 girls) adolescent athletes (age: 15.2 ± 1.5 years; body mass index: 21.2 ± 2.7 kg/m2) participated. A 6-compartment model was used as the reference method (TBProReference) involving air displacement plethysmography for body volume, dual-energy X-ray absorptiometry (DXA) for bone mineral content, and deuterium dilution for total body water (TBW). Alternatively, DXA TBPro models were used as TBPro = lean-soft mass (LSM) − HFFFM × fat-free mass (FFM) − Ms. − G, where LSM and FFM were assessed using DXA, HFFFM is the hydration fraction of the FFM using measured TBW or assumed TBW (adult fraction of 0.732; Lohman’s constants or mean observed HFFFM), Ms. is soft tissue minerals (Ms = 0.0129 × HFFFM × FFM), and G is glycogen calculated as 0.044 × (LSM − HFFFM × FFM − Ms). The maturation level was determined by self-assessment. TBPro obtained from DXA using the assumed HFFFM explained 73% to 77% of the variance compared to TBProReference. Meanwhile, using the mean values of measured HFFFM, the DXA model explained 53 and 36% for boys and girls, respectively. Larger bias (8.6% for boys and 25.8% for girls) and limits of agreement were found for the DXA model using measured HFFFM (boys for 66.9% and girls for 70%) compared to an assumed HFFFM (bias ranged from 1.5% to 22.5% and limits of agreement ranged from 31.3% to 35.3%). Less complex and demanding TBPro DXA models with the assumed HFFFM are valid alternatives for assessing this relevant FFM component in groups of adolescent athletes but are less accurate for individual results. Though future studies should be conducted to test the usefulness of these models in longitudinal and experimental designs, their potential to provide an estimation of protein mass after exercise and diet interventions in young athletes is anticipated.

Seaweeds, also known as marine macroalgae, are renewable biological resources that are found worldwide and possess a wide variety of secondary metabolites, including tannins. Drifted brown seaweed (DBSW) is particularly rich in tannins and is regarded as biological trash. The cotton leaf hopper Amrasca devastans (Distant) has caused both quantitative and qualitative losses in cotton production. Drifted brown seaweeds (DBSWs) were used in this study to extract, qualitatively profile, and quantify the levels of total tannins, condensed tannins, hydrolyzable tannins, and phlorotannins in the seaweeds; test their insecticidal activity; and determine the mechanism of action. The largest amount of tannin extract was found in Sargassum wightii Greville (20.62%) using the Soxhlet method (SM). Significantly higher amounts of hydrolyzable tannins (p = 0.005), soluble phlorotannins (p = 0.005), total tannins in the SM (p = 0.003), and total tannins in the cold percolation method (p = 0.005) were recorded in S. wightii. However, high levels of condensed tannins (CTAs) were observed in Turbinaria ornata (Turner) J. Agardh (p = 0.004). A. devastans nymphs and adults were examined for oral toxicity (OT) and contact toxicity (CT) against DBSW tannin crude extract and column chromatographic fractions 1 (Rf = 0.86) and 2 (Rf = 0.88). Stoechospermum polypodioides (J.V. Lamouroux) J. Agardh crude tannin was highly effective against A. devastans using the OT method (LC50, 0.044%) when compared with the standard gallic acid (LC50, 0.044%) and tannic acid (LC50, 0.122%). Similarly, S. wightii fraction 2 (LC50, 0.007%) showed a greater insecticidal effect against A. devastans adults in OT than gallic acid (LC50, 0.034%) and tannic acid (LC50, 0.022%). The mechanism of action results show that A. devastans adults treated with crude tannin of T. ornata had significantly decreased amylase, protease (p = 0.005), and invertase (p = 0.003) levels when compared with the detoxification enzymes. The levels of glycosidase, lactate dehydrogenase, esterase, lipase, invertase, and acid phosphate activities (p = 0.005) of S. wightii were reduced when compared with those of the Vijayneem and chemical pesticide Monocrotophos. In adult insects treated with LC50 concentrations of S. wightii tannin fraction 1, the total body protein (9.00 µg/µL) was significantly reduced (OT, LC50—0.019%). The SDS-PAGE analysis results also show that S. wightii tannin fraction 1 (OT and CT), fraction 2 (OT), and S. polypodioides fraction 2 (CT) had a significant effect on the total body portion level, appearance, and disappearance of some proteins and polypeptides. This study shows that the selected brown macroalgae can be utilized for the safer management of cotton leaf hoppers. [ABSTRACT FROM AUTHOR]

Background: Bone health and growth during adolescence require adequate total body protein (TBPr). Renutrition for patients with anorexia nervosa (AN) should aim to normalize body composition and to recover both fat mass and TBPr. Objective: We intended to analyze predictors of protein status, including exercise status, in adolescents with AN and to investigate whether weight gain would replenish body protein deficits. Methods: We assessed TBPr in a longitudinal, observational study as height-adjusted nitrogen index (NI) using in vivo neutron activation analysis in 103 adolescents with AN [mean ± SD age, 15.6 ± 1.4 y; body mass index (BMI, in kg/m²), 16.5 ± 1.6] at the commencement of inpatient refeeding (T0), in 56 of these patients 7 mo thereafter as outpatients (T1), and in age-matched controls (C; n = 51, 15.5 ± 2.1 y, BMI 20.7 ± 1.9). Lean tissue and fat mass were assessed by dualenergy X-ray absorptiometry. BMI, BMI standard deviation score, and lean tissue mass were tested as predictors of protein status using receiver operating characteristic analysis. Results: At T0, NI was decreased in AN (AN, 0.88 ± 0.10 compared with C, 1.00 ± 0.08, P < 0.001). In 34%, the patients showed protein depletion. Patients classified as "exercisers" had a higher NI than did "nonexercisers" (0.89 ± 0.11 compared with 0.85 ± 0.08, P = 0.045). BMI, BMI standard deviation score, and lean tissue mass did not show potential as predictors of protein status. Despite increases in weight (+6.9 ± 4.5 kg), and BMI (+2.5 ± 1.7), protein status did not improve (TBPr T0, 8.0 ± 1.1 kg; T1, 8.1 ± 1.0 kg, P = 0.495). In an AN subgroup at 7 mo matched with controls in age (AN, 16.5 ± 1.1 y; C, 16.2 ± 1.8 y) and BMI (AN, 20.5 ± 1.4; C, 20.7 ± 1.3), protein status was still not normalized in AN (NI: AN, 0.89 ± 0.09 compared with C, 1.00 ± 0.07, P < 0.001). Conclusions: Adolescents recovering from AN remained protein depleted at 7 mo after baseline assessment, even though they were weight restored. [ABSTRACT FROM AUTHOR]

Abstract: Elevated resting energy expenditure (REE) is seen in liver cirrhosis and is associated with reduced transplant-free survival. Non-selective β-blockers reduce REE in acute hypermetabolic conditions. We examined whether non-selective β-blockers reduce REE in patients with stable liver cirrhosis. Twenty-two stable cirrhotic patients (Child–Pugh grading: 19A, 2B, 1C) were randomized to 3-month treatment with nadolol (titrated to decrease resting pulse rate by 20%) or placebo and after a 1-month washout period crossed to the alternative treatment for a further 3months. REE was measured by indirect calorimetry and total body protein by neutron activation analysis at the beginning and end of each 3-month period of treatment. A predicted REE was calculated for each patient based on total body protein. A measured to predicted REE ratio >1.22 indicated significantly elevated REE. The primary outcome was REE at the end of 3-month treatment with nadolol compared with placebo. Elevated REE was seen in one patient at study entry. After 3months on placebo REE was 1506±40 (SEM) kcal/d and on nadolol, 1476±40kcal/d, a mean reduction of 31±16kcal/d (P= .076). Total body protein changes were not significant. Nadolol was well tolerated with no increase in the rate of adverse events. In stable cirrhotic patients, nadolol was not associated with reduction in REE. A larger, longer-term study with different eligibility criteria is required to investigate whether this treatment offers benefits additional to its use for prevention of variceal hemorrhage. [Copyright &y& Elsevier]

OBJECTIVE To determine the changes in body composition, muscle function and energy expenditure after radical cystectomy (RC). PATIENTS AND METHODS Eleven consecutive men (median age 66 years, range 44–79) who had a RC over a 1-year period had measurements made of their total body protein, by neutron-activation analysis, total body water by tritium dilution, total body potassium by whole-body counting, resting energy expenditure by indirect calorimetry, and grip strength and respiratory muscle strength. These variables were measured on the day before surgery and at 2 weeks and 6 months after RC. Total body fat was derived using a multicompartment model. Artificial nutritional support was not provided after RC and no oral caloric intake was provided until bowel function returned. RESULTS Five patients were malnourished before RC and four had significant complications afterward. Over the first 2 weeks there were significant losses in mean (sem) protein levels, at 0.68 (0.17) kg ( P < 0.001) and water, at 3.00 (0.73) L ( P < 0.001), while body fat was unchanged. Resting energy expenditure was 11% higher than predicted at 14 days after RC ( P < 0.001). Body potassium changes mirrored the protein changes but were not statistically significant. Over the subsequent 6 months, 63%, i.e. 0.43 (0.24) kg, of the body protein lost after surgery was regained. Muscle function had returned to baseline levels at 6 months. CONCLUSIONS This study shows that the catabolic loss of body protein after RC is not regained by 6 months. Regimens directed at early nutritional support after RC for these patients might improve the recovery of body composition, with consequent clinical benefits. [ABSTRACT FROM AUTHOR]

Aim: Protein energy malnutrition is common in children with chronic renal failure (CRF) and may negatively impact on clinical outcome. Although the aetiology of malnutrition is multifactorial, descriptive information on body composition may guide nutritional interventions aimed at optimising nutritional status. Methods: This prospective cohort study in children with CRF was conducted from April 1999 to November 2000. Patients were categorised according to their glomerular filtration rate (GFR) into CRF and end-stage renal failure (ESRF). Body composition was assessed based on anthropometry, total body potassium (TBK), total body protein (TBP) and dual X-ray absorptiometry (DEXA). Results: Fifteen patients (10 male, 5 female; mean age: 13.4 ± 4.3 years) were studied, including eight patients with CRF (mean GFR: 17.0 ± 7.2 mL/min/1.73 m2) and seven patients with ESRF (mean GFR: 6.4 ± 1.7 mL/min/1.73 m2). Patients in both groups ( n = 15) had deficits in height and TBP (mean z-score height-for-age: −1.19 ± 1.05, P < 0.01; mean z-score TBP: −0.71 ± 0.71, P < 0.05). There were no significant differences in weight, height, fat-free mass, TBK and TBP between patients with CRF and ESRF. Conclusions: Linear growth impairment and decreased TBP are common in children with chronic and ESRF. TBK and DEXA may underestimate the degree of malnutrition in these patients. [ABSTRACT FROM AUTHOR]

Determining body composition in gray seals ( Halichoerus grypus) is important when studying their physiology and life history. In this study we investigated the predictability of total body fat (TBF) and protein (TBP) in postweaned gray seal pups from morphometric measurements, blubber thickness using ultrasonographs and bioelectrical impedance analysis (BIA). In postweaned pups, TBF (kg) could be estimated from girth measurements and sex ( n= 45, r2= 0.878) using hydrogen isotope dilution methods as the reference. However, TBP could not be reliably estimated from morphometric data. TBF (kg) in yearlings was best predicted from mass ( n= 6, r2= 0.776) and TBP (kg) from mass/length ( r2= 0.949). Dorsal blubber thickness using B-mode ultrasound was also a significant predictor of TBF (kg) in postweaned pups ( r2= 0.725) but BIA was not. Marked pups were recaptured during their first few months of life ( n= 48) and body composition changes investigated. Animals lost mass and TBF after leaving the breeding beach, largely during the first 5–6 mo of life. Postweaned pups were ∼40% TBF and ∼13% TBP whereas yearlings were ∼12% TBF and ∼20% TBP. Pups that survived beyond 6 mo of age then regained mass as protein. Morphometric measurements are a useful field indication of body condition when isotope dilution is impractical. [ABSTRACT FROM AUTHOR]

Aims: To define the effects of insulin treatment on body composition and fat distribution, and investigate the potential role of body weight (BWt) gain predictors in patients with poorly controlled type 2 diabetes. Methods: Assessments of body composition, using a four-component model, and biochemical indices were obtained in 19 patients [mean (SD): age, 60 (8.3) years; BMI, 25.3 (3.3) kg/m2] with poorly controlled type 2 diabetes, despite maximal oral hypoglycaemic agents, receiving insulin [40 (12.2) units/day] at baseline and after 1, 3 and 6 months. Results: Insulin therapy significantly reduced plasma glucose [-6.0 (4.3) mmol/l], improved [HbA1c [-1.9 (1.8)%], and reversed the BWt lost [3.3 (1.8) kg] before treatment. The 6-month BWt gain [+5.2 (2.7) kg] consisted of body fat [+2.9 (2.7) kg] and fat-free mass [FFM; +2.3 (1.8) kg], with the FFM increase due solely to total body water [TBW; +2.4 (1.5)1], as there were no detectable changes in total body protein or bone mineral, thereby increasing FFM hydration by 1.3%. More body fat was deposited centrally in patients receiving insulin alone than those receiving insulin with an oral hypoglycaemic agent (metformin). Daily insulin dose, HbA1c and hip circumference were independent predictors of BWt gain. Conclusions: Insulin treatment increased fat and FFM similarly in poorly controlled type 2 diabetes patients, with the FFM gain due entirely to TBW. The possible role of metformin in reducing central fat accumulation following insulin treatment warrants further investigation into its mechanism and potential long-term benefits. [ABSTRACT FROM AUTHOR]

Most reports of outcome following obesity surgery report weight and co-morbidity changes only. We studied body composition changes in 17 adult patients (15 F, 2 M, age 43±2 years, range 28–58 years), with morbid obesity (initial BMI 40.4±4.9 kg/m2, range 34.7–48.8) who were managed surgically by laparoscopically inserting an adjustable gastric band. Body composition was studied before and after surgery (mean interval of 909±51 days, range 441–1,155 days) using anthropometry (abdominal circumference, AC, sum of four skinfold thicknesses, SFSUM), whole-body potassium counting (TBK), in vivo neutron activation analysis total body nitrogen (TBProtein) and whole-body dual-energy ray absorptiometry (total body percent fat TBF%, and total body bone mineral density TBBMD). Weight loss over the study period was 23.4±2.5 kg. (p<0.0003) with an AC reduction of 20.0±4.5 cm (p<0.008). Both SFSUM and TBF% were significantly reduced (p<0.02 and p<0.0005 respectively). Both TBK and TBProtein after normalization for sex and height, were significantly (p<0.0054 and p<0.001 respectively) reduced, but the ratio of loss of fat mass to fat-free mass, at 4.4:1 was usual for weight loss, and there was no significant changes in the ratio of potassium to protein. TBBMD, after normalization relative to a young same sex adult, was not significantly changed. In this group of patients, most of the substantial weight loss over a 2- to 3-year period was due to loss of fat mass, with relatively less reduction in the components of fat-free mass. Adjustable laparoscopic gastric banding induces fat loss without significant other deleterious effects on body composition. [ABSTRACT FROM AUTHOR]

Body composition measurements, including total body nitrogen (TBN) by in vivo neutron activation analysis, were made on 11 female volunteers before and after an 11-wk very-low-calorie diet (VLCD) [1695 kJ (405 kcal) 6.7 g N]. Mean body mass index (BMI) changed from 32.1 to 26.2 kg/m², corresponding to a mean weight loss of 16.2 ± 2.4 (SD) kg. The mean loss of TBN was 125 ± 57 g, equivalent to 781 ± 356 g protein. The fat-free mass (FFM) component of the weight loss was calculated by two different methods as 23.5% (±3% SEM) and 22.8% (±2.7% SEM), respectively, thereby demonstrating the improved protein sparing of ketogenic VLCDs. FFM loss was not clearly related to BMI. [ABSTRACT FROM AUTHOR]