Energy expenditures & physical activity in rats with chronic suboptimal nutrition

BACKGROUND: Sub-optimally nourished rats show reduced growth, biochemical and physiological changes. However, no one has assessed metabolic rate adaptations in rats subjected to chronic suboptimal nutrition (CSN). In this study energy expenditure (EE; kcal/100 g body weight) and physical activity (PA; oscillations in weight/min/kg body weight) were assessed in rats subjected to three levels of CSN. RESULTS: Body weight gain was diminished (76.7 ± 12.0 and 61.6 ± 11.0 g) in rats fed 70 and 60% of the ad-libitum fed controls which gained more weight (148.5 ± 32.3 g). The rats fed 80% gained weight similarly to controls (136.3 ± 10.5 g). Percent Fat-free body mass was reduced (143.8 ± 8.7 and 142.0 ± 7.6 g) in rats fed 70 and 60% of ad-libitum, but not in those fed 80% (200.8 ± 17.5 g) as compared with controls (201.6 ± 33.4 g). Body fat (g) decreased in rats fed 80% (19.7 ± 5.3), 70% (15.3 ± 3.5) and 60% (9.6 ± 2.7) of ad-libitum in comparison to controls (26.0 ± 6.7). EE and PA were also altered by CSN. The control rats increased their EE and PA during the dark periods by 1.4 ± 0.8 and 1.7 ± 1.1 respectively, as compared with light the period; whereas CSN rats fed 80 and 70% of ad-libitum energy intake had reduced EE and PA during the dark periods as compared with the light period EE(7.5 ± 1.4 and 7.8 ± 0.6 vs. 9.0 ± 1.2 and 9.7 ± 0.8; p < 0.05, respectively), PA(3.1 ± 0.8 and 1.6 ± 0.4 vs. 4.1 ± 0.9 and 2.4 ± 0.4; p < 0.05) and RQ (0.87 ± 0.04 and 0.85 ± 0.5; vs. 0.95 ± 0.03 and 0.91 ± 0.05 p < 0.05). In contrast, both light (7.1 ± 1.4) and dark period (6.2 ± 1.0) EE and PA (3.4 ± 0.9 and 2.5 ± 0.5 respectively) were reduced in rats fed 60% of ad-libitum energy intake. CONCLUSION: CSN rats adapt to mild energy restriction by reducing body fat, EE and PA mainly during the dark period while growth proceeds and lean body mass is preserved. At higher levels of energy restrictions there is decreased growth, body fat and lean mass. Moreover EE and PA are also reduced during both light and dark periods

Energy Expenditure and Physical Activity in Recovering Malnourished Infants

Background. Malnourished infants are small for age and weight. Objectives. Determine profiles in 24-hour energy metabolism in recovering malnourished infants and compare to similarly aged healthy controls. Methods. 10 malnourished infants (58.1 ± 5.9 cm, 7.7 ± 5.6 months) were healthy prior to spending 22 hours in the Enhanced Metabolic Testing Activity Chamber for measurement of EE (kcal/min), sleeping metabolic rate (SMR; kcal/min), respiratory quotient (RQ; VCO2/VO2), and physical activity (PA; oscillations in wt/min/kg body weight). Metabolic data were extrapolated to 24 hours (kcal/kg/d). Energy intake (kcal/kg/d) and the proportions (%) of carbohydrate, protein, and fat were calculated. Anthropometrics for malnourished infants were obtained. Statistical differences (P < .05) between groups were determined (SPSS, version 13). Results. In comparison to controls, malnourished infants were lighter (4.1 ± 1.2 versus 7.3 ± 0.8 kg; P < .05), had less body fat % (10.3 ± 7.6 versus 25.7 ± 2.5), and lower BMI (12.0 ± 1.7 versus 15.5 ± 1.5; P < .05). In contrast, they had greater energy intake (142.7 ± 14.6 versus 85.1 ± 25.8; P < .05) with a greater percentage of carbohydrates (55.1 ± 3.9 versus 47.2 ± 5.2; P < .05). However, malnourished infants had greater 24-hour EE (101.3 ± 20.1 versus 78.6 ± 8.4; P < .05), SMR (92.6 ± 17.1 versus 65.0 ± 3.9; P < .05), and RQ (1.00 ± 0.13 versus 0.86 ± 0.08; P < .05) along with a lower amount of PA (2.3 ± 0.94 versus 4.0 ± 1.5; P < .05). Conclusions. Malnourished infants require more energy, possibly for growth

Energy expenditure in chow-fed female non-human primates of various weights

<p>Abstract</p> <p>Background</p> <p>Until now no technology has been available to study energy metabolism in monkeys. The objective of this study was to determine daily energy expenditures (EE) and respiratory quotients (RQ) in female monkeys of various body weights and ages.</p> <p>Methods</p> <p>16 socially reared Bonnet Macaque female monkeys [5.5 ± 1.4 kg body weight, modified BMI (length measurement from head to base of the tail) = 28.8 ± 6.7 kg/crown-rump length, m²and 11.7 ± 4.6 years] were placed in the primate Enhanced Metabolic Testing Activity Chamber (Model 3000a, EMTAC Inc. Santa Barbara, CA) for 22-hour measurements of EE (kcal/kg) and RQ (VCO₂/VO₂). All were fed monkey chow (4.03 kcal/g) ad-libitum under a 12/12 hour light/dark cycle. Metabolic data were corrected for differences in body weight. Results were divided into day (8-hours), dark (12 hours) and morning (2-hours) periods. Data analysis was conducted utilizing SPSS (Version 13).</p> <p>Results</p> <p>Modified BMI negatively correlated with 22-hour energy expenditure in all monkeys (r = -0.80, p < 0.01). The large variability of daily energy intake (4.5 to 102.0 kcal/kg) necessitated division into two groups, non-eaters (< 13 kcal/kg) and eaters (> 23 kcal/kg). There were reductions (p < 0.05) in both 22-hour and dark period RQs in the "non-eaters" in comparison to those who were "eaters". Monkeys were also classified as "lean" (modified BMI < 25) or "obese" (modified BMI > 30). The obese group had lower EE (p < 0.05) during each time period and over the entire 22-hours (p < 0.05), in comparison to their lean counterparts.</p> <p>Conclusion</p> <p>The EMTAC proved to be a valuable tool for metabolic measurements in monkeys. The accuracy and sensitivity of the instrument allowed detection of subtle metabolic changes in relation to energy intake. Moreover, there is an association between a reduction of energy expenditure and a gain in body weight.</p

Twenty-four hour metabolic rate measurements utilized as a reference to evaluate several prediction equations for calculating energy requirements in healthy infants

<p>Abstract</p> <p>Background</p> <p>To date, only short-duration metabolic rate measurements of less than four hours have been used to evaluate prediction equations for calculating energy requirements in healthy infants. Therefore, the objective of this analysis was to utilize direct 24-hour metabolic rate measurements from a prior study to evaluate the accuracy of several currently used prediction equations for calculating energy expenditure (EE) in healthy infants.</p> <p>Methods</p> <p>Data from 24-hour EE, resting (RMR) and sleeping (SMR) metabolic rates obtained from 10 healthy infants, served as a reference to evaluate 11 length-weight (LWT) and weight (WT) based prediction equations. Six prediction equations have been previously derived from 50 short-term EE measurements in the Enhanced Metabolic Testing Activity Chamber (EMTAC) for assessing 24-hour EE, (EMTACEE-LWT and EMTACEE-WT), RMR (EMTACRMR-LWT and EMTACRMR-WT) and SMR (EMTACSMR-LWT and EMTACSMR-WT). The last five additional prediction equations for calculating RMR consisted of the World Health Organization (WHO), the Schofield (SCH-LWT and SCH-WT) and the Oxford (OXFORD-LWT and OXFORD-WT). Paired t-tests and the Bland & Altman limit analysis were both applied to evaluate the performance of each equation in comparison to the reference data.</p> <p>Results</p> <p>24-hour EE, RMR and SMR calculated with the EMTACEE-WT, EMTACRMR-WT and both the EMTACSMR-LWT and EMTACSMR-WT prediction equations were similar, p = NS, to that obtained from the reference measurements. However, RMR calculated using the WHO, SCH-LWT, SCH-WT, OXFORD-LWT and OXFORD-WT prediction equations were not comparable to the direct 24-hour metabolic measurements (p < 0.05) obtained in the 10 reference infants. Moreover, the EMTACEE-LWT and EMTACRMR-LWT were also not similar (p < 0.05) to direct 24-hour metabolic measurements.</p> <p>Conclusions</p> <p>Weight based prediction equations, derived from short-duration EE measurements in the EMTAC, were accurate for calculating EE, RMR and SMR in healthy infants.</p

Relationship between maternal obesity and infant feeding-interactions

BACKGROUND: There are no data regarding the relationship between maternal adiposity and interaction and feeding of infants and possible contribution to childhood obesity. In this study we determined the relationship between maternal body weight and composition and infant feeding patterns and maternal-infant interaction during 24-hour metabolic rate measurements in the Enhanced Metabolic Testing Activity Chamber (EMTAC). METHODS: The amount of time four obese (BMI = 33.5 ± 5.3 kg/m(2)) and three normal weight (BMI = 23.1 ± 0.6 kg/m(2)) biological mothers, spent feeding and interacting with their infants, along with what they ingested, was recorded during 24-hour metabolic rate measurements in the EMTAC. The seven infants were 4.9 ± 0.7 months, 69 ± 3 cm, 7.5 ± 0.8 kg, 26 ± 3 % fat and 29 ± 25 percentile for weight for length. Energy and macronutrient intake (kcal/kg) were assessed. Maternal body composition was determined by air displacement plethysmorgraphy and that of the infants by skin-fold thicknesses. Pearson correlations and independent t-tests were utilized for statistical analysis (p < 0.05). RESULTS: Infants born to obese biological mothers consumed more energy (87.6 ± 18.9 vs. 68.1 ± 17.3) and energy as carbohydrate (25 ± 6 vs.16 ± 3; p < 0.05) than their normal weight counterparts. Most of the increased intake was due to complementary feedings. Twenty-four hour infant energy intake increased with both greater maternal body weight (r = 0.73;p < 0.06) and percent body fat. Furthermore, obese biological mothers spent less total time interacting (570 ± 13 vs. 381 ± 30 minutes) and feeding (298 ± 32 vs.176 ± 22 minutes) (p < 0.05) their infants than their normal weight counterparts. Twenty-four hour interaction time negatively correlated with both maternal body weight (r = -0.98; p < 0.01) and percent body fat (r = -0.92; p < 0.01). Moreover, infants of obese mothers slept more (783 ± 38 vs. 682 ± 32 minutes; p < 0.05) than their normal weight counterparts. However, there were no differences in total 24-hour energy expenditure, resting and sleeping metabolic rates (kcal/kg) for infants born to obese and normal weight biological mothers. CONCLUSION: Greater maternal body weight and percent body fat were associated with greater infant energy intakes. These infants were fed less frequently and consumed more carbohydrates in a shorter period of time as compared to infants from normal weight biological mothers. These variations in feeding patterns may predispose certain infants to obesity

A systematic review, evidence synthesis and meta-analysis of quantitative and qualitative studies evaluating the clinical effectiveness, the cost-effectiveness, safety and acceptability of interventions to prevent postnatal depression

Background: Postnatal depression (PND) is a major depressive disorder in the year following childbirth, which impacts on women, their infants and their families. A range of interventions has been developed to prevent PND. Objectives: To (1) evaluate the clinical effectiveness, cost-effectiveness, acceptability and safety of antenatal and postnatal interventions for pregnant and postnatal women to prevent PND; (2) apply rigorous methods of systematic reviewing of quantitative and qualitative studies, evidence synthesis and decision-analytic modelling to evaluate the preventive impact on women, their infants and their families; and (3) estimate cost-effectiveness. Data sources: We searched MEDLINE, EMBASE, Science Citation Index and other databases (from inception to July 2013) in December 2012, and we were updated by electronic alerts until July 2013. Review methods: Two reviewers independently screened titles and abstracts with consensus agreement. We undertook quality assessment. All universal, selective and indicated preventive interventions for pregnant women and women in the first 6 postnatal weeks were included. All outcomes were included, focusing on the Edinburgh Postnatal Depression Scale (EPDS), diagnostic instruments and infant outcomes. The quantitative evidence was synthesised using network meta-analyses (NMAs). A mathematical model was constructed to explore the cost-effectiveness of interventions contained within the NMA for EPDS values. Results: From 3072 records identified, 122 papers (86 trials) were included in the quantitative review. From 2152 records, 56 papers (44 studies) were included in the qualitative review. The results were inconclusive. The most beneficial interventions appeared to be midwifery redesigned postnatal care [as shown by the mean 12-month EPDS score difference of –1.43 (95% credible interval –4.00 to 1.36)], person-centred approach (PCA)-based and cognitive–behavioural therapy (CBT)-based intervention (universal), interpersonal psychotherapy (IPT)-based intervention and education on preparing for parenting (selective), promoting parent–infant interaction, peer support, IPT-based intervention and PCA-based and CBT-based intervention (indicated). Women valued seeing the same health worker, the involvement of partners and access to several visits from a midwife or health visitor trained in person-centred or cognitive–behavioural approaches. The most cost-effective interventions were estimated to be midwifery redesigned postnatal care (universal), PCA-based intervention (indicated) and IPT-based intervention in the sensitivity analysis (indicated), although there was considerable uncertainty. Expected value of partial perfect information (EVPPI) for efficacy data was in excess of £150M for each population. Given the EVPPI values, future trials assessing the relative efficacies of promising interventions appears to represent value for money. Limitations: In the NMAs, some trials were omitted because they could not be connected to the main network of evidence or did not provide EPDS scores. This may have introduced reporting or selection bias. No adjustment was made for the lack of quality of some trials. Although we appraised a very large number of studies, much of the evidence was inconclusive. Conclusions: Interventions warrant replication within randomised controlled trials (RCTs). Several interventions appear to be cost-effective relative to usual care, but this is subject to considerable uncertainty. Future work recommendations: Several interventions appear to be cost-effective relative to usual care, but this is subject to considerable uncertainty. Future research conducting RCTs to establish which interventions are most clinically effective and cost-effective should be considered

Metal-on-Metal Hip Prostheses and Systemic Health: A Cross-Sectional Association Study 8 Years after Implantation

There is public concern over the long term systemic health effects of metal released from hip replacement prostheses that use large-diameter metal-on-metal bearings. However, to date there has been no systematic study to determine which organs may be at risk, or the magnitude of any effect. We undertook a detailed cross-sectional health screen at a mean of 8 years after surgery in 35 asymptomatic patients who had previously received a metal-on-metal hip resurfacing (MoMHR) versus 35 individually age and sex matched asymptomatic patients who had received a conventional hip replacement. Total body bone mineral density was 5% higher (mean difference 0.05 g/cm2 , P = 0.02) and bone turnover was 14% lower (TRAP 5b, mean difference 20.56IU/L, P = 0.006; osteocalcin, mean difference 23.08 ng/mL, P = 0.03) in the hip resurfacing versus conventional hip replacement group. Cardiac ejection fraction was 7% lower (mean absolute difference 25%, P = 0.04) and left ventricular end-diastolic diameter was 6% larger (mean difference 2.7 mm, P = 0.007) in the hip resurfacing group versus those patients who received a conventional hip replacement. The urinary fractional excretion of metal was low (cobalt 5%, chromium 1.5%) in patients with MoMHR, but creatinine clearance was normal. Diuretic prescription was associated with a 40% increase in the fractional excretion of chromium (mean difference 0.5%, P = 0.03). There was no evidence of difference in neuropsychological, renal tubular, hepatic or endocrine function between groups (P.0.05). Our findings of differences in bone and cardiac function between patient groups suggest that chronic exposure to low elevated metal concentrations in patients with well-functioning MoMHR prostheses may have systemic effects. Long-term epidemiological studies in patients with well-functioning metal on metal hip prostheses should include musculoskeletal and cardiac endpoints to quantitate the risk of clinical disease

Indirect calorimetry evaluations of energy utilization by laying hens: Nutrient and temperature effects.

A four-chamber indirect calorimeter was constructed to evaluate energy utilization by laying hens as affected by dietary energy, protein and amino acid levels and by housing temperature. Heat production was measured by indirect calorimetry and metabolizable energy was determined for each diet. Net energetic efficiency was calculated as the slope of the regression of energy balance (metabolizable energy intake - heat production) on metabolizable energy intake. Hens fed diets formulated without protein specifications to provide amino acid levels equivalent to those provided by 14.5 or 16% protein, had higher (P < .05) net energetic efficiencies than hens fed diets formulated with specified protein levels. Addition of 3% animal fat to the higher (16% protein) amino acid diets produced the greatest increases (P < .05) in net efficiency, but decreased (P < .05) efficiency in the lower (14.5% protein) amino acid diet formulated without a protein specification. Metabolizable energy available for production was improved (P < .05) with animal fat additions to all but the diet formulated to the higher (16% protein) amino acid levels. Animal fat, cottonseed oil, corn oil, cod liver oil and safflower oil were used to determine effects of fat source on energy utilization by laying hens at 21.1 C. Higher net efficiencies were obtained for the cottonseed and safflower oil diets (99.1 and 99.8%, respectively) than for the basal diet (90.6%) or the other fat sources (cod liver oil = 86.0%, corn oil = 87.3%, animal fat = 91.1%). Full vs. meal (two 1-hr periods daily) feeding and total sulfur amino acid deficiency effects on energy utilization were evaluated. Meal feeding reduced (P < .05) metabolizable energy available for production while increasing (P < .05) maintenance metabolizable energy requirements. Feeding regime did not reverse the decline (P < .05) in net efficiency (89.2-89.7 to 81.7-82.6%) observed with total sulfur amino acid deficiency. Hens were fed either 7% animal fat or 7% corn oil and maintained at 10, 21.1 and 32.2 C to study effects of fat source and temperature on energy utilization. From 10 to 32.2 C, net energetic efficiency increased from 87.6 to 92.6% with animal fat. Corn oil showed the highest net efficiency (93.9%) at 10 C, while animal fat was highest (92.6%) at 32.2 C. Hens fed animal fat required the most (P < .05) maintenance metabolizable energy and had the highest (P < .05) fasting heat productions at each temperature