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  1. Comparison of chitosan scaffold and chitosan-collagen scaffold: a preliminary study
    Norazril SA, Aminuddin BS, Norhayati MM, Mazlyzam AL, Fauziah O, Ruszymah BH
    Med J Malaysia, 2004 May;59 Suppl B:186-7.
    PMID: 15468880
    Chitosan has similar structure to glycosaminoglycans in the tissue, thus may be a good candidates as tissue engineering scaffold. However, to improve their cell attachment ability, we try to incorporate this natural polymer with collagen by combining it via cross-linking process. In this preliminary study we evaluate the cell attachment ability of chitosan-collagen scaffold versus chitosan scaffold alone. Chitosan and collagen were dissolved in 1% acetic acid and then were frozen for 24 hours before the lyophilizing process. Human skin fibroblasts were seeded into both scaffold and were cultured in F12: DMEM (1:1). Metabolic activity assay were used to evaluate cell attachment ability of scaffold for a period of 1, 3, 7 and 14 days. Scanning electron micrographs shows good cell morphology on chitosan-collagen hybrid scaffold. In conclusion, the incorporation of collagen to chitosan will enhance its cell attachment ability and will be a potential scaffold in tissue engineering.
    Matched MeSH terms: Energy Metabolism/physiology
  2. Resting metabolic rate in a sample of girls in Malaysia and England
    Henry CJ, Webster-Gandy JD, Koon PB, Ismail MN
    Am J Hum Biol, 2005 Nov-Dec;17(6):818-20.
    PMID: 16254909
    This cross-sectional study of age matched (10-11 years), pre-menarcheal girls in England and Malaysia investigated the effect of ethnicity on resting metabolic rate (RMR). The children were recruited from schools in Oxford, England, and Kuala Lumpur, Malaysia, and all measurements were conducted in the schools. The Malaysian girls were shorter (143.7 +/- 6.5 cm and 140.1 +/- 5.3 cm (mean +/- SD) for the English and Malaysian girls respectively) and lighter (32.5 +/- 5.3 kg compared with 38.0 +/- 8.7 kg for the English girls) with a smaller fat mass and fat free mass (FFM) than the English girls. Energy expenditure was lower in the Malaysian girls (4555 +/- 531 kJ/day compared with 5178 +/- 688 kJ/day for the English girls). Although a difference in RMR was observed between the two groups, when corrected for body composition the difference was no longer significant. No effect of ethnicity on the relationship of FFM and RMR was shown when the data were analyzed using analysis of covariance.
    Matched MeSH terms: Energy Metabolism/physiology*
  3. Fulltext Dietary intake, physical activity and energy expenditure of Malaysian adolescents
    Zalilah MS, Khor GL, Mirnalini K, Norimah AK, Ang M
    Singapore Med J, 2006 Jun;47(6):491-8.
    PMID: 16752017
    INTRODUCTION: Paediatric obesity is a public health concern worldwide as it can track into adulthood and increase the risk of adult morbidity and mortality. While the aetiology of obesity is multi-factorial, the roles of diet and physical activity are controversial. Thus, the purpose of this study was to report on the differences in energy intake, diet composition, time spent doing physical activity and energy expenditure among underweight (UW), normal weight (NW) and at-risk of overweight (OW) Malaysian adolescents (317 females and 301 males) aged 11-15 years.
    METHODS: This was a cross-sectional study with 6,555 adolescents measured for weights and heights for body mass index (BMI) categorisation. A total of 618 subjects were randomly selected from each BMI category according to gender. The subjects' dietary intake and physical activity were assessed using self-reported three-day food and activity records, respectively. Dietary intake components included total energy and macronutrient intakes. Energy expenditure was calculated as a sum of energy expended for basal metabolic rate and physical activity. Time spent (in minutes) in low, medium and high intensity activities was also calculated.
    RESULTS: The OW adolescents had the highest crude energy intake and energy expenditure. However, after adjusting for body weight, the OW subjects had the lowest energy intake and energy expenditure (p-value is less than 0.001). The study groups did not differ significantly in time spent for low, medium and high intensity activities. Macronutrient intakes differed significantly only among the girls where the OW group had the highest intakes compared to UW and NW groups (p-value is less than 0.05). All study groups had greater than 30 percent and less than 55 percent of energy intake from fat and carbohydrate, respectively.
    CONCLUSION: The data suggested that a combination of low energy expenditure adjusted for body weight and high dietary fat intake may be associated with overweight and obesity among adolescents. To prevent overweight and obesity among children and adolescents, strategies that address eating behaviours and physical activity are required. Various segments of the society must be involved in efforts to promote healthful dietary intakes and active lifestyle in children and adolescents.
    Matched MeSH terms: Energy Metabolism/physiology*
  4. Fulltext Gliding saves time but not energy in Malayan colugos
    Byrnes G, Libby T, Lim NT, Spence AJ
    J Exp Biol, 2011 Aug 15;214(Pt 16):2690-6.
    PMID: 21795564 DOI: 10.1242/jeb.052993
    Gliding is thought to be an economical form of locomotion. However, few data on the climbing and gliding of free-ranging gliding mammals are available. This study employed an animal-borne three-dimensional acceleration data-logging system to collect continuous data on the climbing and gliding of free-ranging Malayan colugos, Galeopterus variegatus. We combined these movement data with empirical estimates of the metabolic costs to move horizontally or vertically to test this long-standing hypothesis by determining whether the metabolic cost to climb to sufficient height to glide a given distance was less than the cost to move an equivalent distance horizontally through the canopy. On average, colugos climb a short distance to initiate glides. However, due to the high energetic cost of climbing, gliding is more energetically costly to move a given horizontal distance than would be predicted for an animal travelling the same distance through the canopy. Furthermore, because colugos spend a small fraction of their time engaged in locomotor activity, the high costs have little effect on their overall energy budget. As a result, the energetic economy hypothesis for the origins of gliding is not supported. It is likely that other ecologically relevant factors have played a greater role in the origins of gliding in colugos and other mammals.
    Matched MeSH terms: Energy Metabolism/physiology*
  5. Association between physical activity and metabolic syndrome among Malay adults in a developing country, Malaysia
    Chu AH, Moy FM
    J Sci Med Sport, 2014 Mar;17(2):195-200.
    PMID: 23665093 DOI: 10.1016/j.jsams.2013.04.003
    Metabolic syndrome is a highly prevalent health problem within the adult population in developing countries. We aimed to study the association of physical activity levels and metabolic risk factors among Malay adults in Malaysia.
    Matched MeSH terms: Energy Metabolism/physiology
  6. Fulltext Sharp turning and corner turning: comparison of energy expenditure, gait parameters, and level of fatigue among community-dwelling elderly
    Justine M, Manaf H, Sulaiman A, Razi S, Alias HA
    Biomed Res Int, 2014;2014:640321.
    PMID: 24977154 DOI: 10.1155/2014/640321
    This study compares energy expenditure (EE), gait parameters (GP), and level of fatigue (LOF) between 5-minute walking with sharp turning (ST) and corner turning (CT). Data were obtained from 29 community-dwelling elderly (mean age, 62.7 ± 3.54 years). For 5 minutes, in ST task, participants walked on a 3-meter pathway with 2 cones placed at each end (180° turning), while in CT task, participants walked on a 6-meter pathway with 4 cones placed at 4 corners (90° turning). The physiological cost index, pedometer, and 10-point Modified Borg Dyspnoea Scale were used to measure EE (beats/min), GP (no of steps), and LOF, respectively. Data were analyzed by using independent t-tests. EE during ST (0.62 ± 0.21 beats/min) was significantly higher than CT (0.48 ± 0.17 beats/min) (P < 0.05). GP (434 ± 92.93 steps) and LOF (1.40 ± 1.11) in ST were found to be lower compared to GP (463 ± 92.18 steps) and LOF (1.54 ± 1.34) in CT (All, P > 0.05). Higher EE in ST could be due to the difficulty in changing to a 180° direction, which may involve agility and different turning strategies (step-turn or pivot-turn) to adjust the posture carefully. In CT, participants could choose a step-turn strategy to change to a 90° direction, which was less challenging to postural control.
    Matched MeSH terms: Energy Metabolism/physiology*
  7. The combined effect of hypoxia and nutritional status on metabolic and ionoregulatory responses of common carp (Cyprinus carpio)
    Moyson S, Liew HJ, Diricx M, Sinha AK, Blust R, De Boeck G
    Comp Biochem Physiol A Mol Integr Physiol, 2015 Jan;179:133-43.
    PMID: 25263807 DOI: 10.1016/j.cbpa.2014.09.017
    In the present study, the combined effects of hypoxia and nutritional status were examined in common carp (Cyprinus carpio), a relatively hypoxia tolerant cyprinid. Fish were either fed or fasted and were exposed to hypoxia (1.5-1.8mg O2L(-1)) at or slightly above their critical oxygen concentration during 1, 3 or 7days followed by a 7day recovery period. Ventilation initially increased during hypoxia, but fasted fish had lower ventilation frequencies than fed fish. In fed fish, ventilation returned to control levels during hypoxia, while in fasted fish recovery only occurred after reoxygenation. Due to this, C. carpio managed, at least in part, to maintain aerobic metabolism during hypoxia: muscle and plasma lactate levels remained relatively stable although they tended to be higher in fed fish (despite higher ventilation rates). However, during recovery, compensatory responses differed greatly between both feeding regimes: plasma lactate in fed fish increased with a simultaneous breakdown of liver glycogen indicating increased energy use, while fasted fish seemed to economize energy and recycle decreasing plasma lactate levels into increasing liver glycogen levels. Protein was used under both feeding regimes during hypoxia and subsequent recovery: protein levels reduced mainly in liver for fed fish and in muscle for fasted fish. Overall, nutritional status had a greater impact on energy reserves than the lack of oxygen with a lower hepatosomatic index and lower glycogen stores in fasted fish. Fasted fish transiently increased Na(+)/K(+)-ATPase activity under hypoxia, but in general ionoregulatory balance proved to be only slightly disturbed, showing that sufficient energy was left for ion regulation.
    Matched MeSH terms: Energy Metabolism/physiology
  8. Fulltext Neurohormetic phytochemicals: An evolutionary-bioenergetic perspective
    Murugaiyah V, Mattson MP
    Neurochem Int, 2015 Oct;89:271-80.
    PMID: 25861940 DOI: 10.1016/j.neuint.2015.03.009
    The impact of dietary factors on brain health and vulnerability to disease is increasingly appreciated. The results of epidemiological studies, and intervention trials in animal models suggest that diets rich in phytochemicals can enhance neuroplasticity and resistance to neurodegeneration. Here we describe how interactions of plants and animals during their co-evolution, and resulting reciprocal adaptations, have shaped the remarkable characteristics of phytochemicals and their effects on the physiology of animal cells in general, and neurons in particular. Survival advantages were conferred upon plants capable of producing noxious bitter-tasting chemicals, and on animals able to tolerate the phytochemicals and consume the plants as an energy source. The remarkably diverse array of phytochemicals present in modern fruits, vegetables spices, tea and coffee may have arisen, in part, from the acquisition of adaptive cellular stress responses and detoxification enzymes in animals that enabled them to consume plants containing potentially toxic chemicals. Interestingly, some of the same adaptive stress response mechanisms that protect neurons against noxious phytochemicals are also activated by dietary energy restriction and vigorous physical exertion, two environmental challenges that shaped brain evolution. In this perspective article, we describe some of the signaling pathways relevant to cellular energy metabolism that are modulated by 'neurohormetic phytochemicals' (potentially toxic chemicals produced by plants that have beneficial effects on animals when consumed in moderate amounts). We highlight the cellular bioenergetics-related sirtuin, adenosine monophosphate activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and insulin-like growth factor 1 (IGF-1) pathways. The inclusion of dietary neurohormetic phytochemicals in an overall program for brain health that also includes exercise and energy restriction may find applications in the prevention and treatment of a range of neurological disorders.
    Matched MeSH terms: Energy Metabolism/physiology*
  9. Cortisol affects metabolic and ionoregulatory responses to a different extent depending on feeding ration in common carp, Cyprinus carpio
    Liew HJ, Fazio A, Faggio C, Blust R, De Boeck G
    Comp Biochem Physiol A Mol Integr Physiol, 2015 Nov;189:45-57.
    PMID: 26219478 DOI: 10.1016/j.cbpa.2015.07.011
    Interacting effects of feeding and stress on corticoid responses in fish were investigated in common carp fed 3.0% or 0.5% body mass (BM) which received no implant, a sham or a cortisol implant (250 mg/kg BM) throughout a 168 hour post-implant period (168 h-PI). At 12h-PI, cortisol implants elevated plasma cortisol, glucose and lactate. Plasma osmolality and ions remained stable, but cortisol increased gill and kidney Na(+)/K(+) ATPase (NKA) and H(+) ATPase activities. Gill NKA activities were higher at 3%-BM, whereas kidney H(+) ATPase activity was greater at 0.5%-BM. Cortisol induced liver protein mobilization and repartitioned liver and muscle glycogen. At 3%-BM, this did not increase plasma ammonia, reflecting improved excretion efficiency concomitant with upregulation of Rhesus glycoprotein Rhcg-1 in gill. Responses in glucocorticoid receptors (GR1/GR2) and mineralocorticoid receptor (MR) to cortisol elevation were most prominent in kidney with increased expression of all receptors at 24 h-PI at 0.5%-BM, but only GR2 and MR at 0.5%-BM. In the liver, upregulation of all receptors occurred at 24 h-PI at 3%-BM, whilst only GR2 and MR were upregulated at 0.5%-BM. In the gill, there was a limited upregulation: GR2 and MR at 72 h-PI and GR1 at 168 h-PI at 3%-BM but only GR2 at 72 h-PI at 0.5%-BM. Thus cortisol elevation led to similar expression patterns of cortisol receptors in both feeding regimes, while feeding affected the type of receptor that was induced. Induction of corticoid receptors occurred simultaneously with increases in Rhcg-1 mRNA expression (gill) but well after NKA and H(+) ATPase activities increased (gill/kidney).
    Matched MeSH terms: Energy Metabolism/physiology
  10. Fulltext Importance of silicon and mechanisms of biosilica formation in plants
    Sahebi M, Hanafi MM, Siti Nor Akmar A, Rafii MY, Azizi P, Tengoua FF, et al.
    Biomed Res Int, 2015;2015:396010.
    PMID: 25685787 DOI: 10.1155/2015/396010
    Silicon (Si) is one of the most prevalent macroelements, performing an essential function in healing plants in response to environmental stresses. The purpose of using Si is to induce resistance to distinct stresses, diseases, and pathogens. Additionally, Si can improve the condition of soils, which contain toxic levels of heavy metals along with other chemical elements. Silicon minimizes toxicity of Fe, Al, and Mn, increases the availability of P, and enhances drought along with salt tolerance in plants through the formation of silicified tissues in plants. However, the concentration of Si depends on the plants genotype and organisms. Hence, the physiological mechanisms and metabolic activities of plants may be affected by Si application. Peptides as well as amino acids can effectively create polysilicic species through interactions with different species of silicate inside solution. The carboxylic acid and the alcohol groups of serine and asparagine tend not to engage in any significant role in polysilicates formation, but the hydroxyl group side chain can be involved in the formation of hydrogen bond with Si(OH)4. The mechanisms and trend of Si absorption are different between plant species. Furthermore, the transportation of Si requires an energy mechanism; thus, low temperatures and metabolic repressors inhibit Si transportation.
    Matched MeSH terms: Energy Metabolism/physiology*
  11. Fulltext Synchronous activity lowers the energetic cost of nest escape for sea turtle hatchlings
    Rusli MU, Booth DT, Joseph J
    J Exp Biol, 2016 05 15;219(Pt 10):1505-13.
    PMID: 27207954 DOI: 10.1242/jeb.134742
    A potential advantage of group movement in animals is increased locomotion efficiency. This implies a reduced energetic cost for individuals that occur in larger groups such as herds, flocks and schools. When chelonian hatchlings hatch in the underground nest with finite energy for their post-hatching dispersal phase, they face the challenge of minimizing energetic expenditure while escaping the nest. The term 'social facilitation' has been used to describe the combined digging effort of sea turtle hatchlings during nest escape. Given that in a normal clutch, a substantial part of the energy reserve within the residual yolk is used by hatchlings in the digging out process, a decreased cohort size may reduce the energy reserve available to cross the beach and sustain the initial swimming frenzy. This hypothesis was experimentally tested by varying cohort size in hatchling green turtles (Chelonia mydas) and measuring energy expenditure during the nest escape process using open-flow respirometry. The energetic cost of escaping through 40 cm of sand was calculated to vary between 4.4 and 28.3 kJ per individual, the cost decreasing as the number of individuals in the cohort increased. This represents 11-68% of the energy contained in a hatchling's residual yolk at hatching. The reduced energetic cost associated with large cohorts resulted from both a lower metabolic rate per individual and a shortened nest escape time. We conclude that synchronous digging activity of many hatchlings during nest escape evolved not only to facilitate rapid nest emergence but also to reduce the energetic cost to individuals.
    Matched MeSH terms: Energy Metabolism/physiology*
  12. Fulltext Agarolytic bacterium Persicobacter sp. CCB-QB2 exhibited a diauxic growth involving galactose utilization pathway
    Furusawa G, Lau NS, Suganthi A, Amirul AA
    Microbiologyopen, 2017 02;6(1).
    PMID: 27987272 DOI: 10.1002/mbo3.405
    The agarolytic bacterium Persicobacter sp. CCB-QB2 was isolated from seaweed (genus Ulva) collected from a coastal area of Malaysia. Here, we report a high-quality draft genome sequence for QB2. The Rapid Annotation using Subsystem Technology (RAST) annotation server identified four β-agarases (PdAgaA, PdAgaB, PdAgaC, and PdAgaD) as well as galK, galE, and phosphoglucomutase, which are related to the Leloir pathway. Interestingly, QB2 exhibited a diauxic growth in the presence of two kinds of nutrients, such as tryptone and agar. In cells grown with agar, the profiles of agarase activity and growth rate were very similar. galK, galE, and phosphoglucomutase genes were highly expressed in the second growth phase of diauxic growth, indicating that QB2 cells use galactose hydrolyzed from agar by its agarases and exhibit nutrient prioritization. This is the first report describing diauxic growth for agarolytic bacteria. QB2 is a potential novel model organism for studying diauxic growth in environmental bacteria.
    Matched MeSH terms: Energy Metabolism/physiology*
  13. Effects of short-term step aerobics exercise on bone metabolism and functional fitness in postmenopausal women with low bone mass
    Wen HJ, Huang TH, Li TL, Chong PN, Ang BS
    Osteoporos Int, 2017 02;28(2):539-547.
    PMID: 27613719 DOI: 10.1007/s00198-016-3759-4
    Measurement of bone turnover markers is an alternative way to determine the effects of exercise on bone health. A 10-week group-based step aerobics exercise significantly improved functional fitness in postmenopausal women with low bone mass, and showed a positive trend in reducing resorption activity via bone turnover markers.

    INTRODUCTION: The major goal of this study was to determine the effects of short-term group-based step aerobics (GBSA) exercise on the bone metabolism, bone mineral density (BMD), and functional fitness of postmenopausal women (PMW) with low bone mass.

    METHODS: Forty-eight PMW (aged 58.2 ± 3.5 years) with low bone mass (lumbar spine BMD T-score of -2.00 ± 0.67) were recruited and randomly assigned to an exercise group (EG) or to a control group (CG). Participants from the EG attended a progressive 10-week GBSA exercise at an intensity of 75-85 % of heart rate reserve, 90 min per session, and three sessions per week. Serum bone metabolic markers (C-terminal telopeptide of type 1 collagen [CTX] and osteocalcin), BMD, and functional fitness components were measured before and after the training program. Mixed-models repeated measures method was used to compare differences between the groups (α = 0.05).

    RESULTS: After the 10-week intervention period, there was no significant exercise program by time interaction for CTX; however, the percent change for CTX was significantly different between the groups (EG = -13.1 ± 24.4 % vs. CG = 11.0 ± 51.5 %, P 

    Matched MeSH terms: Energy Metabolism/physiology
  14. Fulltext Exergaming boxing versus heavy-bag boxing: are these equipotent for individuals with spinal cord injury?
    Mat Rosly M, Mat Rosly H, Hasnan N, Davis GM, Husain R
    Eur J Phys Rehabil Med, 2017 Aug;53(4):527-534.
    PMID: 28092144 DOI: 10.23736/S1973-9087.17.04456-2
    BACKGROUND: Current strategies for increased physical activity and exercise in individuals with spinal cord injury (SCI) face many challenges with regards to maintaining their continuity of participation. Barriers cited often include problems with accessing facilities, mundane, monotonous or boring exercises and expensive equipment that is often not adapted for wheelchair users.

    AIM: To compare the physiological responses and user preferences between conventional heavy-bag boxing against a novel form of video game boxing, known as exergaming boxing.

    DESIGN: Cross-sectional study.

    SETTING: Exercise laboratory setting in a university medical center.

    POPULATION: Seventeen participants with SCI were recruited, of which sixteen were male and only one female. Their mean age was 35.6±10.2 years.

    METHODS: All of them performed a 15-minute physical exercise session of exergaming and heavy-bag boxing in a sitting position. The study assessed physiological responses in terms of oxygen consumption, metabolic equivalent (MET) and energy expenditure between exergaming and heavy-bag boxing derived from open-circuit spirometry. Participants also rated their perceived exertion using Borg's category-ratio ratings of perceived exertion.

    RESULTS: Both exergaming (MET: 4.3±1.0) and heavy-bag boxing (MET: 4.4±1.0) achieved moderate exercise intensities in these participants with SCI. Paired t-test revealed no significant differences (P>0.05, Cohen's d: 0.02-0.49) in the physiological or perceived exertional responses between the two modalities of boxing. Post session user survey reported all the participants found exergaming boxing more enjoyable.

    CONCLUSIONS: Exergaming boxing, was able to produce equipotent physiological responses as conventional heavy-bag boxing. The intensity of both exercise modalities achieved recommended intensities for health and fitness benefits.

    CLINICAL REHABILITATION IMPACT: Exergaming boxing have the potential to provide an enjoyable, self-competitive environment for moderate-vigorous exercise even at the comfort of their homes.

    Matched MeSH terms: Energy Metabolism/physiology*
  15. Fulltext The Role of Eif6 in Skeletal Muscle Homeostasis Revealed by Endurance Training Co-expression Networks
    Clarke K, Ricciardi S, Pearson T, Bharudin I, Davidsen PK, Bonomo M, et al.
    Cell Rep, 2017 Nov 07;21(6):1507-1520.
    PMID: 29117557 DOI: 10.1016/j.celrep.2017.10.040
    Regular endurance training improves muscle oxidative capacity and reduces the risk of age-related disorders. Understanding the molecular networks underlying this phenomenon is crucial. Here, by exploiting the power of computational modeling, we show that endurance training induces profound changes in gene regulatory networks linking signaling and selective control of translation to energy metabolism and tissue remodeling. We discovered that knockdown of the mTOR-independent factor Eif6, which we predicted to be a key regulator of this process, affects mitochondrial respiration efficiency, ROS production, and exercise performance. Our work demonstrates the validity of a data-driven approach to understanding muscle homeostasis.
    Matched MeSH terms: Energy Metabolism/physiology
  16. Emerging Role of Adipocytokines in Type 2 Diabetes as Mediators of Insulin Resistance and Cardiovascular Disease
    Jaganathan R, Ravindran R, Dhanasekaran S
    Can J Diabetes, 2018 Aug;42(4):446-456.e1.
    PMID: 29229313 DOI: 10.1016/j.jcjd.2017.10.040
    Adipose tissue is an enormously active endocrine organ, secreting various hormones, such as adiponectin, leptin, resistin and visfatin, together with classical cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). All these adipocytokines play significant roles in the regulation of energy metabolism, glucose and lipid metabolism, reproduction, cardiovascular function and immunity. Adipocytokines are significantly regulated by nutritional status and can directly influence other organ systems, including brain, liver and skeletal muscle. Adiponectin plays a key role as an anti-inflammatory hormone. Upregulated expression of resistin, vaspin, apelin and TNF-α plays a significant role in induction of insulin resistance linked with obesity and type 2 diabetes. Ghrelin, the circulating peptide, has been found to stimulate appetite and regulate energy balance. Thus, it can be considered 1 of the candidate genes for obesity and type 2 diabetes. Omentin is a novel adipokine produced by visceral adipose tissue. Circulating levels of omentin are decreased in insulin-resistant states, for example, in obesity and diabetes. IL-6 plays a vital role in regulating the accumulation of lipids intramyocardially. Based on the biologic relevance of these adipocytokines, they can no longer be considered as energy storage sites alone but must also be considered in metabolic control. Hence, the present review summarizes the regulatory roles of adipocytokines in diabetes linked with obesity.
    Matched MeSH terms: Energy Metabolism/physiology
  17. Dynamic characterisation of Össur Flex-Run prosthetic feet for a more informed prescription
    Noroozi S, Ong ZC, Khoo SY, Aslani N, Sewell P
    Prosthet Orthot Int, 2019 Feb;43(1):62-70.
    PMID: 30051756 DOI: 10.1177/0309364618789449
    BACKGROUND:: The current method of prescribing composite running-specific energy-storing-and-returning feet is subjective and is based only on the amputee's static body weight/mass.

    OBJECTIVES:: The aim was to investigate their dynamic characteristics and create a relationship between these dynamic data and the prescription of foot.

    STUDY DESIGN:: Experimental Assessment.

    METHODS:: This article presents the modal analysis results of the full range of Össur Flex-Run™ running feet that are commercially available (1LO-9LO) using experimental modal analysis technique under a constant mass at 53 kg and boundary condition.

    RESULTS:: It was shown that both the undamped natural frequency and stiffness increase linearly from the lowest to the highest stiffness category of foot which allows for a more informed prescription of foot when tuning to a matched natural frequency. The low damping characteristics determined experimentally that ranged between 1.5% and 2.0% indicates that the feet require less input energy to maintain the steady-state cyclic motion before take-off from the ground. An analysis of the mode shapes also showed a unique design feature of these feet that is hypothesised to enhance their performance.

    CONCLUSION:: A better understanding of dynamic characteristics of the feet can help tune the feet to the user's requirements in promoting a better gait performance.

    CLINICAL RELEVANCE: The dynamic data determined from this study are needed to better inform the amputees in predicting the natural frequency of the foot prescribed. The amputees can intuitively tune the cyclic body rhythm during walking or running to match with the natural frequency. This could eventually promote a better gait performance.

    Matched MeSH terms: Energy Metabolism/physiology
  18. Fulltext The implications of time on the ground on running economy: less is not always better
    Lussiana T, Patoz A, Gindre C, Mourot L, Hébert-Losier K
    J Exp Biol, 2019 03 18;222(Pt 6).
    PMID: 30787136 DOI: 10.1242/jeb.192047
    A lower duty factor (DF) reflects a greater relative contribution of leg swing versus ground contact time during the running step. Increasing time on the ground has been reported in the scientific literature to both increase and decrease the energy cost (EC) of running, with DF reported to be highly variable in runners. As increasing running speed aligns running kinematics more closely with spring-mass model behaviours and re-use of elastic energy, we compared the centre of mass (COM) displacement and EC between runners with a low (DFlow) and high (DFhigh) duty factor at typical endurance running speeds. Forty well-trained runners were divided in two groups based on their mean DF measured across a range of speeds. EC was measured from 4 min treadmill runs at 10, 12 and 14 km h-1 using indirect calorimetry. Temporal characteristics and COM displacement data of the running step were recorded from 30 s treadmill runs at 10, 12, 14, 16 and 18 km h-1 Across speeds, DFlow exhibited more symmetrical patterns between braking and propulsion phases in terms of time and vertical COM displacement than DFhigh DFhigh limited global vertical COM displacements in favour of horizontal progression during ground contact. Despite these running kinematics differences, no significant difference in EC was observed between groups. Therefore, both DF strategies seem energetically efficient at endurance running speeds.
    Matched MeSH terms: Energy Metabolism/physiology*
  19. The energetic brain - A review from students to students
    Bordone MP, Salman MM, Titus HE, Amini E, Andersen JV, Chakraborti B, et al.
    J Neurochem, 2019 10;151(2):139-165.
    PMID: 31318452 DOI: 10.1111/jnc.14829
    The past 20 years have resulted in unprecedented progress in understanding brain energy metabolism and its role in health and disease. In this review, which was initiated at the 14th International Society for Neurochemistry Advanced School, we address the basic concepts of brain energy metabolism and approach the question of why the brain has high energy expenditure. Our review illustrates that the vertebrate brain has a high need for energy because of the high number of neurons and the need to maintain a delicate interplay between energy metabolism, neurotransmission, and plasticity. Disturbances to the energetic balance, to mitochondria quality control or to glia-neuron metabolic interaction may lead to brain circuit malfunction or even severe disorders of the CNS. We cover neuronal energy consumption in neural transmission and basic ('housekeeping') cellular processes. Additionally, we describe the most common (glucose) and alternative sources of energy namely glutamate, lactate, ketone bodies, and medium chain fatty acids. We discuss the multifaceted role of non-neuronal cells in the transport of energy substrates from circulation (pericytes and astrocytes) and in the supply (astrocytes and microglia) and usage of different energy fuels. Finally, we address pathological consequences of disrupted energy homeostasis in the CNS.
    Matched MeSH terms: Energy Metabolism/physiology*
  20. Fulltext Maximum acceptable frequency of lift for combined manual material handling task in Malaysia
    Widia M, Md Dawal SZ, Yusoff N
    PLoS One, 2019;14(5):e0216918.
    PMID: 31141545 DOI: 10.1371/journal.pone.0216918
    BACKGROUND: Extensive studies have been carried out over the years to determine the maximum acceptable weight that a worker is capable of lifting in a given situation among Occidental populations across Europe and US. Nonetheless, studies that place emphasis on using lifting frequency as the quantifying task parameter, especially in developing countries such as Malaysia, appear to be in scarcity. Hence, this study determined the maximum acceptable frequency of lift (MAFL) for combined manual material handling (MMH) tasks amongst Malaysian males.

    METHOD: Two lifting loads were considered in this study: 1 kg and 5 kg. Each subject adjusted his frequency of lifting using a psychophysical approach. The subjects were instructed to perform combined MMH task as fast as they could over a period of 45 minutes without exhausting themselves or becoming overheated. The physiological response energy expenditure was recorded during the experimental sessions. The ratings of perceived exertion (RPE) for four body parts (forearms, upper arm, lower back and entire body) were recorded after the subjects had completed the instructed task.

    RESULTS: The mean frequencies of the MMH task had been 6.8 and 5.5 cycles/minute for lifting load of 1 and 5 kg, respectively, while the mean energy expenditure values were 4.16 and 5.62 kcal/min for 1 and 5 kg load, respectively. These displayed a significant difference in the Maximum Acceptable Frequency of Lift (MAFL) between the two loads, energy expenditure and RPE (p < 0.05) whereby the subjects appeared to work harder physiologically for heavier load.

    CONCLUSION: It can be concluded that it is significant to assess physiological response and RPE in determining the maximum acceptable lifting frequency at varied levels of load weight. The findings retrieved in this study can aid in designing tasks that do not exceed the capacity of workers in order to minimise the risk of WRMSDs.

    Matched MeSH terms: Energy Metabolism/physiology*
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