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1.
Br J Nutr ; 131(3): 489-499, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-37726106

RESUMO

In chronic spinal cord injury (SCI), individuals experience dietary inadequacies complicated by an understudied research area. Our objectives were to assess (1) the agreement between methods of estimating energy requirement (EER) and estimated energy intake (EEI) and (2) whether dietary protein intake met SCI-specific protein guidelines. Persons with chronic SCI (n = 43) completed 3-day food records to assess EEI and dietary protein intake. EER was determined with the Long and Institute of Medicine (IOM) methods and the SCI-specific Farkas method. Protein requirements were calculated as 0·8-1·0 g/kg of body weight (BW)/d. Reporting accuracy and bias were calculated and correlated to body composition. Compared with IOM and Long methods (P < 0·05), the SCI-specific method did not overestimate the EEI (P = 0·200). Reporting accuracy and bias were best for SCI-specific (98·9 %, -1·12 %) compared with Long (94·8 %, -5·24 %) and IOM (64·1 %, -35·4 %) methods. BW (r = -0·403), BMI (r = -0·323) and total fat mass (r = -0·346) correlated with the IOM reporting bias (all, P < 0·05). BW correlated with the SCI-specific and Long reporting bias (r = -0·313, P = 0·041). Seven (16 %) participants met BW-specific protein guidelines. The regression of dietary protein intake on BW demonstrated no association between the variables (ß = 0·067, P = 0·730). In contrast, for every 1 kg increase in BW, the delta between total and required protein intake decreased by 0·833 g (P = 0·0001). The SCI-specific method for EER had the best agreement with the EEI. Protein intake decreased with increasing BW, contrary to protein requirements for chronic SCI.


Assuntos
Ingestão de Energia , Traumatismos da Medula Espinal , Humanos , Proteínas Alimentares/metabolismo , Metabolismo Energético , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/metabolismo , Peso Corporal , Composição Corporal
2.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36694952

RESUMO

Microbial growth requires energy for maintaining the existing cells and producing components for the new ones. Microbes therefore invest a considerable amount of their resources into proteins needed for energy harvesting. Growth in different environments is associated with different energy demands for growth of yeast Saccharomyces cerevisiae, although the cross-condition differences remain poorly characterized. Furthermore, a direct comparison of the energy costs for the biosynthesis of the new biomass across conditions is not feasible experimentally; computational models, on the contrary, allow comparing the optimal metabolic strategies and quantify the respective costs of energy and nutrients. Thus in this study, we used a resource allocation model of S. cerevisiae to compare the optimal metabolic strategies between different conditions. We found that S. cerevisiae with respiratory-impaired mitochondria required additional energetic investments for growth, while growth on amino acid-rich media was not affected. Amino acid supplementation in anaerobic conditions also was predicted to rescue the growth reduction in mitochondrial respiratory shuttle-deficient mutants of S. cerevisiae. Collectively, these results point to elevated costs of resolving the redox imbalance caused by de novo biosynthesis of amino acids in mitochondria. To sum up, our study provides an example of how resource allocation modeling can be used to address and suggest explanations to open questions in microbial physiology.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces , Saccharomyces cerevisiae/metabolismo , Saccharomyces/metabolismo , Biomassa , Mitocôndrias/metabolismo , Aminoácidos/metabolismo , Respiração , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
3.
J Hepatol ; 77(1): 98-107, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35090958

RESUMO

BACKGROUND & AIMS: Malnutrition is associated with adverse clinical outcomes in patients with cirrhosis. Accurate assessment of energy requirements is needed to optimize dietary intake. Resting energy expenditure (REE), the major component of total energy expenditure, can be measured using indirect calorimetry (mREE) or estimated using prediction equations (pREE). This study assessed the usefulness of predicted estimates of REE in this patient population. METHODS: Individual mREE data were available for 900 patients with cirrhosis (mean [±1 SD] age 55.7±11.6 years-old; 70% men; 52% south-east Asian) and 282 healthy controls (mean age 36.0±12.8 years-old; 52% men; 18% south-east Asian). Metabolic status was classified using thresholds based on the mean ± 1 SD of the mREE in the healthy controls. Comparisons were made between mREE and pREE estimates obtained using the Harris-Benedict, Mifflin, Schofield and Henry equations. Stepwise regression was used to build 3 new prediction models which included sex, ethnicity, body composition measures, and model for end-stage liver disease scores. RESULTS: The mean mREE was significantly higher in patients than controls when referenced to dry body weight (22.4±3.8 cf. 20.8±2.6 kcal/kg/24 hr; p <0.001); there were no significant sex differences. The mean mREE was significantly higher in Caucasian than Asian patients (23.1±4.4 cf. 21.7±2.9 kcal/kg/24 hr; p <0.001). Overall, 37.1% of Caucasian and 25.3% of Asian patients were classified as hypermetabolic. The differences between mREE and pREE were both statistically and clinically relevant; in the total patient population, pREE estimates ranged from 501 kcal/24 hr less to 548 kcal/24 hr more than the mREE. Newly derived prediction equations provided better estimates of mREE but still had limited clinical utility. CONCLUSIONS: Prediction equations do not provide useful estimates of REE in patients with cirrhosis. REE should be directly measured. LAY SUMMARY: People with cirrhosis are often malnourished and this has a detrimental effect on outcome. Provision of an adequate diet is very important and is best achieved by measuring daily energy requirements and adjusting dietary intake accordingly. Prediction equations, which use information on age, sex, weight, and height can be used to estimate energy requirements; however, the results they provide are not accurate enough for clinical use, particularly as they vary according to sex and ethnicity.


Assuntos
Doença Hepática Terminal , Desnutrição , Adulto , Idoso , Metabolismo Basal , Metabolismo Energético , Feminino , Humanos , Cirrose Hepática/complicações , Masculino , Desnutrição/etiologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
4.
Annu Rev Nutr ; 41: 1-18, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115517

RESUMO

After I studied medicine, my career took an early and unusual course when I was offered a clinical research post in Jamaica dealing with childhood malnutrition, of which I knew nothing. My subsequent nutritional explorations allowed gastrointestinal and metabolic analyses to have an impact on several public health policies. The biggest challenges came from unexpected political demands: coping with poor school performers in the Caribbean; addressing UK public health initiatives in health education; breaking the siege of Sarajevo; developing a Food Standards Agency as a sudden need for Tony Blair as incoming prime minister; dealing with widespread bovine spongiform encephalopathy in Europe; and responding to a United Nations request to assess global malnutrition. This last task revealed the need for a lifelong approach to nutrition, which also encompassed pregnancy. But perhaps the biggest challenge was establishing the criteria for obesity assessment, management, and prevention for policy makers across the globe.


Assuntos
Desnutrição , Criança , Feminino , Humanos , Desnutrição/diagnóstico , Desnutrição/prevenção & controle , Estado Nutricional , Obesidade , Gravidez , Saúde Pública , Política Pública
5.
Nutr Health ; 28(3): 297-300, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35435744

RESUMO

Background: The Canada's Food Guide (CFG) encourages Canadians to consume a balanced plate. However, this recommendation may not meet the nutritional needs of young athletes who have increased nutritional requirements. Aim: To evaluate how the 2019 CGF can be used to meet the nutritional needs of young athletes. Method: Five menu scenarios were created using the CFG's balanced plate and recipes from Health Canada. Each menu was analyzed to compare nutrient and energy needs of an index athlete (15-year-old male, 71 kg). Estimated energy requirements were based on nutrition guidelines set by National and International sports-nutrition position statements. Results: The adjusted CFG balanced plate plus an energy dense beverage at every meal was the closest to meeting the index athlete's nutrient requirements. Conclusion: The 2019 CFG's balanced plate needs to be adjusted to meet the nutritional requirements of individuals with active lifestyles.


Assuntos
Alimentos , Política Nutricional , Adolescente , Atletas , Canadá , Humanos , Masculino , Necessidades Nutricionais
6.
Trends Biochem Sci ; 41(2): 175-189, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26520801

RESUMO

The Type III secretion system (T3SS) is a protein export pathway that is widespread in Gram-negative bacteria and delivers effector proteins directly into eukaryotic cells. At its core lie the injectisome (a sophisticated transmembrane secretion apparatus) and a complex network of specialized chaperones that target secretory proteins to the antechamber of the injectisome. The assembly of the system, and the subsequent secretion of proteins through it, undergo fine-tuned, hierarchical regulation. Here, we present the current understanding of the injectisome assembly process, secretion hierarchy, and the role of chaperones. We discuss these events in light of available structural and biochemical dissection and propose future directions essential to revealing mechanistic insight into this fascinating nanomachine.


Assuntos
Bactérias Gram-Negativas/metabolismo , Nanotecnologia , Proteínas de Bactérias/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-31955221

RESUMO

Eusocial bee foragers leave their nest with nectar as flight fuel, therewith reducing the risk of starvation during a foraging trip. Yet, the extra mass results in an increase of energetic expenditure for flight. Thus, bees should tune their fuel loads to the respective foraging situation. In the present study, we investigated the fuel adjustment in the Brazilian stingless bee Melipona subnitida (Apidae, Meliponini). Specifically, we examined whether foragers of this species increase their fuel loads when they have low expectation for nectar collection during a foraging trip. Crop load measurements revealed that nectar foragers carried significantly less fuel on departing the nest than foragers collecting either pollen, clay, or resin. Surprisingly, 75% of nectar foragers left the nest without any detectable amount of nectar, which suggests that the majority of bees collected at nearby nectar sources and avoided an increase in foraging costs. Moreover, foragers increased their fuel loading when repeatedly experiencing empty food sources that had previously been rewarding. These results support our hypothesis and demonstrate that the capability of fuel adjustment is not restricted to honey bees.


Assuntos
Abelhas/fisiologia , Animais , Abelhas/metabolismo , Comportamento Animal/fisiologia , Comportamento Alimentar , Voo Animal , Néctar de Plantas/metabolismo , Pólen/metabolismo , Inanição
8.
Naturwissenschaften ; 106(7-8): 36, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203436

RESUMO

Availability of food resources affects animal survival and reproduction. Thus, coping with changes in food availability is one of the most crucial behavioural and physiological processes in wildlife. Food intake is a key concept in animal ecology that is directly conditioned by food quality and abundance or diet choice, but may also vary according to individual-related factors (e.g. foraging behaviours, social rank or energy-demanding periods) and the influence of the endocrine system on energy metabolism. Here, we studied food intake in relation to individual characteristics (sex, breeding condition and age) and whether steroid hormones (testosterone and corticosterone metabolites) mediate food intake in wild wood mouse (Apodemus sylvaticus). Field work was carried out in February-March 2014 in Monte de Valdelatas (Madrid, Spain). Wood mice were live-trapped for 10 consecutive days in four independent plots. Traps were baited with 4 g of toasted corn and food intake was calculated by subtracting the remaining bait found inside traps. Fresh faecal samples from 130 different wood mice were collected and faecal testosterone and corticosterone metabolites (FTM and FCM, respectively) were analysed by enzyme immunoassays. Food intake was higher in females than males, probably due to greater energy requirements. Non-breeders and young individuals also showed a higher food intake. These individuals usually hold a lower social rank which is associated to limited food resources because of dominants; thus, increased food intake may be a result of freely exploit food bait inside traps while avoiding risky competition. In addition, food intake negatively correlated with FTM levels and positively with FCM levels indicating that both hormones have an active role mediating food intake in the wood mouse. Our data suggest that food intake is a function of both individual traits and the endocrine system that accordingly respond throughout different energy-demanding periods.


Assuntos
Ingestão de Alimentos , Hormônios Esteroides Gonadais/metabolismo , Murinae/fisiologia , Animais , Corticosterona/análise , Dieta , Metabolismo Energético , Fezes/química , Feminino , Masculino , Camundongos , Espanha , Testosterona/análise
9.
Br J Nutr ; 120(10): 1107-1116, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30401004

RESUMO

Intermittent energy restriction (IER) involves short periods of severe energy restriction interspersed with periods of adequate energy intake, and can induce weight loss. Insulin sensitivity is impaired by short-term, complete energy restriction, but the effects of IER are not well known. In randomised order, fourteen lean men (age: 25 (sd 4) years; BMI: 24 (sd 2) kg/m2; body fat: 17 (4) %) consumed 24-h diets providing 100 % (10 441 (sd 812) kJ; energy balance (EB)) or 25 % (2622 (sd 204) kJ; energy restriction (ER)) of estimated energy requirements, followed by an oral glucose tolerance test (OGTT; 75 g of glucose drink) after fasting overnight. Plasma/serum glucose, insulin, NEFA, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP) and fibroblast growth factor 21 (FGF21) were assessed before and after (0 h) each 24-h dietary intervention, and throughout the 2-h OGTT. Homoeostatic model assessment of insulin resistance (HOMA2-IR) assessed the fasted response and incremental AUC (iAUC) or total AUC (tAUC) were calculated during the OGTT. At 0 h, HOMA2-IR was 23 % lower after ER compared with EB (P<0·05). During the OGTT, serum glucose iAUC (P<0·001), serum insulin iAUC (P<0·05) and plasma NEFA tAUC (P<0·01) were greater during ER, but GLP-1 (P=0·161), GIP (P=0·473) and FGF21 (P=0·497) tAUC were similar between trials. These results demonstrate that severe energy restriction acutely impairs postprandial glycaemic control in lean men, despite reducing HOMA2-IR. Chronic intervention studies are required to elucidate the long-term effects of IER on indices of insulin sensitivity, particularly in the absence of weight loss.


Assuntos
Glicemia/análise , Ingestão de Energia , Jejum , Teste de Tolerância a Glucose , Insulina/sangue , Adulto , Área Sob a Curva , Restrição Calórica/métodos , Metabolismo Energético , Fatores de Crescimento de Fibroblastos/metabolismo , Polipeptídeo Inibidor Gástrico , Peptídeo 1 Semelhante ao Glucagon/sangue , Glucose/metabolismo , Voluntários Saudáveis , Humanos , Resistência à Insulina , Masculino , Obesidade/metabolismo , Período Pós-Prandial , Redução de Peso , Adulto Jovem
10.
Br J Nutr ; 119(7): 782-791, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29569541

RESUMO

Currently, energy evaluation of fish feeds is performed on a digestible energy basis. In contrast to net energy (NE) evaluation systems, digestible energy evaluation systems do not differentiate between the different types of digested nutrients regarding their potential for growth. The aim was to develop an NE evaluation for fish by estimating the energy efficiency of digestible nutrients (protein, fat and carbohydrates) and to assess whether these efficiencies differed between Nile tilapia and rainbow trout. Two data sets were constructed. The tilapia and rainbow data set contained, respectively, eight and nine experiments in which the digestibility of protein, fat and energy and the complete energy balances for twenty-three and forty-five diets was measured. The digestible protein (dCP), digestible fat (dFat) and digestible carbohydrate intakes (dCarb) were calculated. By multiple regression analysis, retained energy (RE) was related to dCP, dFat and dCarb. In tilapia, all digestible nutrients were linearly related to RE (P<0·001). In trout, RE was quadratically related to dCarb (P<0·01) and linearly to dCP and dFat (P<0·001). The NE formula was NE=11·5×dCP+35·8×dFAT+11·3×dCarb for tilapia and NE=13·5×dCP+33·0×dFAT+34·0×dCarb-3·64×(dCarb)2 for trout (NE in kJ/(kg0·8×d); dCP, dFat and dCarb in g/(kg0·8×d)). In tilapia, the energetic efficiency of dCP, dFat and dCarb was 49, 91 and 66 %, respectively, showing large similarity with pigs. Tilapia and trout had similar energy efficiencies of dCP (49 v. 57 %) and dFat (91 v. 84 %), but differed regarding dCarb.


Assuntos
Ração Animal/análise , Ciclídeos/crescimento & desenvolvimento , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Oncorhynchus mykiss/crescimento & desenvolvimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura , Dieta/veterinária , Feminino , Masculino
11.
Cell Mol Biol (Noisy-le-grand) ; 64(10): 12-19, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30084811

RESUMO

Oogenesis is a lengthy, multi-step process occurring in mammals yielding single or multiple oocytes capable of being fertilized upon interaction with male gametes. The overall process is highly complex in nature, starting in the primordial follicles, and its ultimate completion is preceded by the meiotic cycle. There are two major phases in oogenesis: the growth phase, followed by a maturation phase that requires relatively less time. Both phases require energy for the various metabolic processes of the oocytes. The energy requirements and the timing of maturation vary significantly among mammalian species. This review describes the variations in the mammalian oocytes development and their energy requirements. It covers the types of mitochondria, the distribution of their changes, and the metabolic processes occurring during the oogenesis in different mammalian species. Oocyte abnormalities associated with glucose deficiency in mammals are discussed, along with the role of fat and protein as alternative energy substrates. The review concludes with recommendations for future studies on oogenesis in mammalian species in the context of energy requirements.


Assuntos
Metabolismo Energético , Oócitos/citologia , Oogênese , Animais , Feminino , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos , Oócitos/metabolismo
12.
Eur J Appl Physiol ; 118(12): 2563-2576, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30187127

RESUMO

PURPOSE: Recent studies have suggested that turning is power intensive. Given the sporadic and irregular movement patterns of children, such findings have important implications for the assessment of true energy expenditure associated with habitual physical activity. The purpose of this study was to investigate the influence of walking speed and angle, and their interaction, on the energy expenditure of healthy children. METHODS: 20 children (10.1 ± 0.5 years; 10 boys) participated in the study. On two separate days, participants completed a turning protocol involving 3-min bouts of walking at one of the 16 speed (2.5, 3.5, 4.5, and 5.5 km h- 1) and angle (0°, 45°, 90°, and 180°) combinations, interspersed by 3 min seated rest. The movement involved 5 m straight walking interspaced with prescribed turns with speed dictated by a digital, auditory metronome. Breath-by-breath gas exchange was measured, in addition to tri-axial acceleration and magnetic field intensity recorded at 100 Hz. RESULTS: Mixed models revealed a significant main effect for speed (p < 0.006) and angle (p < 0.006), with no significant interaction between speed and angle (p > 0.006). Significant differences to straight-line walking energy expenditure within speed were established for 3.5 and 5.5 km h- 1 for 180° turns (~ 13% and ~ 30% increase, respectively). CONCLUSION: These findings highlight the importance of accounting for the magnitude and frequency of turns completed when estimating children's habitual physical activity and have significant implications for the assessment of daily energy expenditure.


Assuntos
Metabolismo Energético , Velocidade de Caminhada , Fenômenos Biomecânicos , Criança , Feminino , Humanos , Masculino
13.
Eur J Appl Physiol ; 118(3): 647-656, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29353321

RESUMO

Criterion data for total energy expenditure (TEE) in elite rugby are lacking, which prediction equations may not reflect accurately. This study quantified TEE of 27 elite male rugby league (RL) and rugby union (RU) players (U16, U20, U24 age groups) during a 14-day in-season period using doubly labelled water (DLW). Measured TEE was also compared to estimated, using prediction equations. Resting metabolic rate (RMR) was measured using indirect calorimetry, and physical activity level (PAL) estimated (TEE:RMR). Differences in measured TEE were unclear by code and age (RL 4369 ± 979; RU 4365 ± 1122; U16, 4010 ± 744; U20, 4414 ± 688; U24, 4761 ± 1523 Kcal day- 1). Differences in PAL (overall mean 2.0 ± 0.4) were unclear. Very likely differences were observed in RMR by code (RL 2366 ± 296; RU 2123 ± 269 Kcal day- 1). Differences in relative RMR between U20 and U24 were very likely (U16, 27 ± 4; U20, 23 ± 3; U24, 26 ± 5 Kcal kg- 1 day- 1). Differences were observed between measured and estimated TEE, using Schofield, Cunningham and Harris-Benedict equations for U16 (187 ± 614, unclear; - 489 ± 564, likely and - 90 ± 579, unclear Kcal day- 1), U20 (- 449 ± 698, likely; - 785 ± 650, very likely and - 452 ± 684, likely Kcal day- 1) and U24 players (- 428 ± 1292; - 605 ± 1493 and - 461 ± 1314 Kcal day- 1, all unclear). Rugby players have high TEE, which should be acknowledged. Large inter-player variability in TEE was observed demonstrating heterogeneity within groups, thus published equations may not appropriately estimate TEE.


Assuntos
Calorimetria/métodos , Metabolismo Energético , Futebol Americano/fisiologia , Adolescente , Calorimetria/normas , Óxido de Deutério/farmacocinética , Humanos , Masculino , Isótopos de Oxigênio/farmacocinética , Adulto Jovem
14.
Br J Nutr ; : 1-11, 2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27831459

RESUMO

The aim of this study was to analyse the association between plain water intake and glycated Hb (HbA1c) in the National Diet and Nutrition Survey (2008-2012) rolling survey. These data included diet (4-d diaries) and HbA1c (fasted blood sample) measures of 456 men and 579 women aged 44 (sd 18) years with full information on covariates of interest (age, ethnicity, BMI, smoking status, education, other beverage intake, energy intake and fibre). Data were analysed using sex-stratified linear and logistic regressions modelling the associations of cups per d (240 ml) of plain water with HbA1c, and odds of HbA1c≥5·5 %, respectively. Substitution analyses modelled the replacement of sugar-sweetened beverages, fruit juice and artificially sweetened beverages with plain water. After adjustment, 1 cup/d of plain water was associated with a -0·04 % lower HbA1c (95 % CI -0·07, -0·02) in men. In logistic regression, men had a 22 % (95 % CI 10, 32 %) reduced odds of HbA1c≥5·5 %/cup per d of plain water. There was no evidence of an association with either HbA1c or odds of HbA1c≥5·5 % in women. None of the substitution models was associated with a change in odds of HbA1c≥5·5 %. Plain water intake was associated with lower HbA1c in men but not in women. Substituting water for specific beverages was not associated with a reduced odds of HbA1c≥5·5 %, suggesting that the addition of water is the more pertinent factor. Future trials should test whether the relationships between water intake and HbA1c is causal as this could be a cost-effective and simple health intervention.

15.
J Anim Physiol Anim Nutr (Berl) ; 100(2): 294-300, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26249003

RESUMO

Previous research on energy requirements of female Saanen goats, using the factorial approach, has not considered the specific requirements for maintenance and growth during the pubertal phase. Thus, the purpose of this study was to estimate energy requirements for maintenance (Trial 1) and growth (Trial 2) of non-pregnant and non-lactating female Saanen goats at the pubertal phase from 30 to 45 kg. In Trial 1, the net energy requirements for maintenance (NEm ) were estimated using 18 female Saanen goats randomly assigned to three levels of intake: ad libitum, and 70% and 40% of ad libitum intake. These animals were pair-fed in six slaughter groups, each consisting of one animal for each level of intake. In Trial 2, the net energy requirements for growth (NEg ) were estimated using 18 female Saanen goats, which were fed ad libitum and slaughtered at targeted BW of 30, 38 and 45 kg. The NEm was 52 kcal/kg(0.75) of BW. The NEg increased from 3.5 to 4.7 Mcal/kg of BW gain as BW increased from 30 to 45 kg. Our results suggest that the guidelines of the major feeding systems for the entire growth phase may not be adequate for females at pubertal phase.


Assuntos
Ração Animal/análise , Dieta/veterinária , Metabolismo Energético/fisiologia , Cabras/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ingestão de Energia/fisiologia , Feminino
16.
Pediatr Nephrol ; 30(11): 1995-2001, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25980467

RESUMO

BACKGROUND: Meeting energy requirements of children with chronic kidney disease (CKD) is paramount to optimising growth and clinical outcome, but little information on this subject has been published. In this study, we examined basal metabolic rate (BMR; a component of energy expenditure) with the aim to determine whether it is related to kidney function independently of weight, height and lean body mass (LBM). METHODS: Twenty children with CKD and 20 healthy age- and gender-matched control children were studied on one occasion. BMR was measured by indirect open circuit calorimetry and predicted by the Schofield equation. Estimated glomerular filtration rate (eGFR) was related to BMR and adjusted for weight, height, age and LBM measured by skinfold thickness. RESULTS: The adjusted BMR of children with CKD did not differ significantly from that of healthy subjects (1296 ± 318 vs.1325 ± 178 kcal/day; p = 0.720). Percentage of predicted BMR also did not differ between the two groups (102 ± 12% vs. 99 ± 14%; p = 0.570). Within the CKD group, eGFR (mean 33.7 ± 20.5 mL/min/m(2)) was significantly related to BMR (ß 0.3, r = 0.517, p = 0.019) independently of nutritional status and LBM. CONCLUSIONS: It seems reasonable to use estimated average requirement as the basis of energy prescriptions for children with CKD (mean CKD stage 3 disease). However, those who were sicker had significantly lower metabolic rates.


Assuntos
Metabolismo Basal/fisiologia , Insuficiência Renal Crônica/metabolismo , Calorimetria Indireta , Criança , Feminino , Humanos , Masculino
17.
J Hum Nutr Diet ; 28(1): 72-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24527991

RESUMO

BACKGROUND: Accurate assessment of energy expenditure and anthropometry in older people is important for targeted nutritional support. The present study aimed to compare measured and calculated resting metabolic rate (m-RMR and c-RMR) and measured, calculated and estimated weight and height in older people aged ≥70 years. METHODS: Participants were healthy older people aged ≥70 years. Indirect calorimetry using a ventilated hood calorimeter was performed for 30 min on fasted participants, and was compared with c-RMR, as calculated using six commonly used equations. Measured, calculated and estimated height and weight were compared. RESULTS: Subjects comprised 14 males and 20 females and mean (SD) m-RMR was 5243 (845) kJ day(-1) [1253 (202) kcal day(-1) ]. The Mifflin St-Jeor equation was the most consistently accurate, with the smallest mean difference between m-RMR and c-RMR of 58 (553) kJ day(-1) [14 (132) kcal day(-1) ] and c-RMR was within 10% of m-RMR in the greatest number of participants (n = 24; 70%). The Schofield equation was among the least accurate in this age group. In older males, self-reported height and weight were accurate, whereas, in females or those unable to self-report height, ulna length was the most accurate alternative to measured height. CONCLUSIONS: Current equations used to calculate RMR in older people have inaccuracies, although the Mifflin St-Jeor equation was most accurate. Future studies should investigate the validity, reliability, cost and practicality of using fat free mass as an item in novel equations to calculate RMR in this age group. Self-reported height and weight in males, and height calculated from ulna length in females, were the most accurate alternatives to measured values in the present study.


Assuntos
Metabolismo Basal , Peso Corporal , Idoso , Idoso de 80 Anos ou mais , Estatura , Índice de Massa Corporal , Calorimetria Indireta/métodos , Metabolismo Energético , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Autorrelato
18.
J Hum Evol ; 77: 167-78, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25439708

RESUMO

Energetic approaches have been increasingly used to address key issues in Neandertal palaeoecology and palaeobiology. Previous research has focused exclusively on the energy requirements of adults and highlights the high energy demands of these individuals compared with modern humans. Less attention has been paid to the energy requirements of sub-adult Neandertals, even though this age group could provide clues for a better understanding of Neandertal life history. Accordingly, herein, we estimate the energy costs of maintenance and growth in Neandertal infants and children from one to six years of age and compare these costs with values for modern humans. Statural growth models for two modern human populations (Beasain and Evenki) and an average Neandertal model population are used to establish weight growth models. In turn, these models of body weight growth are used to estimate key components of energetic variables (basal metabolic rate, total energy expenditure, energy of growth and daily energy requirements). Between three and six years of age, Neandertal children have slightly lower basal and growth energy costs than do modern humans of the same age, due primarily to their smaller body mass and slower growth rates. The reduction in energy allocated to growth is likely the result of metabolic adaptations to other somatic factors and thermal stress. Data from contemporary human infants and children suggest that even mild cold stress increases non-shivering thermogenesis, thus elevating metabolic needs by 50% or more. These results suggest that thermal stress likely played a strong role in shaping the delayed developmental patterns and lower energy allocated to growth during early life in Neandertals relative to Homo sapiens.


Assuntos
Metabolismo Basal/fisiologia , Homem de Neandertal/crescimento & desenvolvimento , Animais , Estatura/fisiologia , Regulação da Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Criança , Pré-Escolar , Metabolismo Energético , Feminino , Humanos , Lactente , Masculino
19.
J Exp Biol ; 217(Pt 20): 3700-7, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25320270

RESUMO

Most studies analyzing the effects of global warming on wild populations focus on gradual temperature changes, yet it is also important to understand the impact of extreme climatic events. Here we studied the effect of two cold spells (January 1985 and February 2012) on the energetics of greater flamingos (Phoenicopterus roseus) in the Camargue (southern France). To understand the cause of observed flamingo mass mortalities, we first assessed the energy stores of flamingos found dead in February 2012, and compared them with those found in other bird species exposed to cold spells and/or fasting. Second, we evaluated the monthly energy requirements of flamingos across 1980-2012 using the mechanistic model Niche Mapper. Our results show that the body lipids of flamingos found dead in 2012 corresponded to 2.6±0.3% of total body mass, which is close to results found in woodcocks (Scolopax rusticola) that died from starvation during a cold spell (1.7±0.1%), and much lower than in woodcocks which were fed throughout this same cold spell (13.0±2%). Further, Niche Mapper predicted that flamingo energy requirements were highest (+6-7%) during the 1985 and 2012 cold spells compared with 'normal' winters. This increase was primarily driven by cold air temperatures. Overall, our findings strongly suggest that flamingos starved to death during both cold spells. This study demonstrates the relevance of using mechanistic energetics modelling and body condition analyses to understand and predict the impact of extreme climatic events on animal energy balance and winter survival probabilities.


Assuntos
Aves/fisiologia , Temperatura Baixa/efeitos adversos , Metabolismo Energético , Inanição/mortalidade , Animais , Aves/metabolismo , Charadriiformes/metabolismo , Charadriiformes/fisiologia , Clima , França , Lipídeos/análise , Modelos Biológicos , Estações do Ano
20.
Clin Nutr ; 43(11): 54-64, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39342800

RESUMO

BACKGROUND & AIMS: Breast cancer (BC) is frequently linked with obesity, metabolic syndrome, and sarcopenia. Therefore, measuring or accurately estimating resting energy expenditure (REE) is crucial for tailoring nutritional needs, managing weight and prevent under- or over-nutrition. We aimed to measure and compare REE between women with BC and a matched control group. Moreover, the prediction accuracy of selected formulas was evaluated. METHODS: Women aged ≥18 years with newly diagnosis of BC (stage 0-III) and body mass index (BMI) ≤ 30 kg/m2 were included in this cross-sectional analysis. Anthropometry, indirect calorimetry, and bioelectrical impedance analysis (BIA) were performed. Patients with BC data were compared to healthy women with similar age and BMI range. Measured REE (mREE) was compared against 15 predictive equations. Agreement between methods was evaluated using Bland-Altman analysis. RESULTS: We included 106 women with BC (age 49.9 ± 11.1 years and BMI 24.5 ± 2.8 kg/m2) and 75 women as control group. There were no differences in age, anthropometry, and BIA variables between groups, except for percentage fat mass. Measured REE values, alone and adjusted for fat-free mass (FFM) and age, were higher in patients with BC compared to controls (+4.3 % and +6.1 %, respectively). Regarding REE prediction, most of the selected equations underestimated mREE. Precision varied widely, with the two Marra equations showing the highest agreement (73 % and 74.5 %) along with the Müller equation (74 %), however, the wide limit of agreement range indicates substantial variability. CONCLUSIONS: Women with early-stage BC exhibited higher mREE compared to controls, albeit its clinical significance is unknown. None of the selected predictive equations provided accurate and precise REE estimates in this group. Although the Marra equation displayed the highest agreement, further studies are needed to evaluate REE variability and its prediction in women with BC.

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