Locomotor Adaptation Improves Balance Control, Multitasking Ability and Reduces the Metabolic Cost of Postural Instability

Science.gov (United States)

Bloomberg, J. J.; Peters, B. T.; Mulavara, A. P.; Brady, R. A.; Batson, C. D.; Miller, C. A.; Ploutz-Snyder, R. J.; Guined, J. R.; Buxton, R. E.; Cohen, H. S.

2011-01-01

During exploration-class missions, sensorimotor disturbances may lead to disruption in the ability to ambulate and perform functional tasks during the initial introduction to a novel gravitational environment following a landing on a planetary surface. The overall goal of our current project is to develop a sensorimotor adaptability training program to facilitate rapid adaptation to these environments. We have developed a unique training system comprised of a treadmill placed on a motion-base facing a virtual visual scene. It provides an unstable walking surface combined with incongruent visual flow designed to enhance sensorimotor adaptability. Greater metabolic cost incurred during balance instability means more physical work is required during adaptation to new environments possibly affecting crewmembers? ability to perform mission critical tasks during early surface operations on planetary expeditions. The goal of this study was to characterize adaptation to a discordant sensory challenge across a number of performance modalities including locomotor stability, multi-tasking ability and metabolic cost. METHODS: Subjects (n=15) walked (4.0 km/h) on a treadmill for an 8 -minute baseline walking period followed by 20-minutes of walking (4.0 km/h) with support surface motion (0.3 Hz, sinusoidal lateral motion, peak amplitude 25.4 cm) provided by the treadmill/motion-base system. Stride frequency and auditory reaction time were collected as measures of locomotor stability and multi-tasking ability, respectively. Metabolic data (VO2) were collected via a portable metabolic gas analysis system. RESULTS: At the onset of lateral support surface motion, subj ects walking on our treadmill showed an increase in stride frequency and auditory reaction time indicating initial balance and multi-tasking disturbances. During the 20-minute adaptation period, balance control and multi-tasking performance improved. Similarly, throughout the 20-minute adaptation period, VO2 gradually

Association Between Energy Balance and Metabolic Hormone Suppression During Ultraendurance Exercise.

Science.gov (United States)

Geesmann, Bjoern; Gibbs, Jenna C; Mester, Joachim; Koehler, Karsten

2017-08-01

Ultraendurance athletes often accumulate an energy deficit when engaging in ultraendurance exercise, and on completion of the exercise, they exhibit endocrine changes that are reminiscent of starvation. However, it remains unclear whether these endocrine changes are a result of the exercise per se or secondary to the energy deficit and, more important, whether these changes can be attenuated by increased dietary intake. The goal of the study was to assess the relationship between changes in key metabolic hormones after ultraendurance exercise and measures of energy balance. Metabolic hormones, as well as energy intake and expenditure, were assessed in 14 well-trained male cyclists who completed a 1230-km ultraendurance cycling event. After completion of the event, serum testosterone (-67% ± 18%), insulin-like growth factor-1 (IGF-1) (-45% ± 8%), and leptin (-79% ± 9%) were significantly suppressed (P deficit to a 3593-kcal surplus. The marked suppression of testosterone, IGF-1, and leptin after ultraendurance exercise is comparable to changes occurring during acute starvation. The suppression of IGF-1, but not that of other metabolic hormones, was strongly associated with the magnitude of the energy deficit, indicating that athletes who attained a greater energy deficit exhibited a more pronounced drop in IGF-1. Future studies are needed to determine whether increased dietary intake can attenuate the endocrine response to ultraendurance exercise.

Errors in potassium balance

International Nuclear Information System (INIS)

Forbes, G.B.; Lantigua, R.; Amatruda, J.M.; Lockwood, D.H.

1981-01-01

Six overweight adult subjects given a low calorie diet containing adequate amounts of nitrogen but subnormal amounts of potassium (K) were observed on the Clinical Research Center for periods of 29 to 40 days. Metabolic balance of potassium was measured together with frequent assays of total body K by 40 K counting. Metabolic K balance underestimated body K losses by 11 to 87% (average 43%): the intersubject variability is such as to preclude the use of a single correction value for unmeasured losses in K balance studies

Metabolic balances of 210Pb and 210Po at natural levels

International Nuclear Information System (INIS)

Spencer, H.; Holtzman, R.B.; Kramer, L.; Ilcewicz, F.H.

1977-01-01

Metabolic balances of 210 Po and 210 Pb were determined under strictly controlled dietary conditions in adult males. The intakes of the two nuclides were due to the dietary contents of these radioisotopes, inhalation from the atmosphere, and smoking of cigarettes. No additional radioisotope was given. The mean dietary intake of 210 Pb was 1.25 pCi/day and of 210 Po, 1.63 pCi/day. The major pathway of excretion of both nuclides is via the gastrointestinal tract and the urinary excretion is much lower. The total excretions of 210 Pb and 210 Po were greater than the dietary intake and the overall balances were -0.28 and -0.16 pCi/day for the two nuclides, respectively, during a low calcium intake. The 210 Pb balances did not change significantly when the calcium intake was increased 7- to 10-fold except for one patient in whom the balance became more negative. The 210 Po balance was more negative during calcium intakes of 800 and 2200 mg than during a low calcium intake of 200 mg/day. The urinary and fecal excretions of the two radionuclides were not affected by the intake of sodium fluoride, while the diuretic compound Hydrodiuril appeared to decrease the fecal 210 Pb excretion

Metabolic balances of 210Pb and 210Po at natural levels

International Nuclear Information System (INIS)

Spencer, H.; Holtzman, R.B.; Kramer, L.; Ilcewicz, F.H.

1977-01-01

Metabolic balances of 210 Po and 210 Pb were determined under strictly controlled dietary conditions in adult males. The intakes of the two nuclides were due to the dietary contents of these radioisotopes, inhalation from the atmosphere, and smoking of cigarettes. No additional radioisotope was given. The mean dietary intake of 210 Pb was 1.25 pCi/day and of 210 Po, 1.63 pCi/day. The major pathway of excretion of both nuclides is via the gastrointestinal tract; the urinary excretion is much lower. The total excretions of 210 Pb and 210 Po were greater than the dietary intake and the overall balances were -0.28 and -0.16 pCi/day for the two nuclides, respectively, during a low calcium intake. The 210 Pb balances did not change significantly when the calcium intake was increased 7- to 10-fold except for one patient in whom the balance became more negative. The 210 Po balance was more negative during calcium intakes of 800 and 2200 mg than during a low calcium intake of 200 mg/day. The urinary and fecal excretions of the two radionuclides were not affected by the intake of sodium fluoride, while the diuretic compound, Hydrodiuril, appeared to decrease the fecal 210 Pb excretion

Initial water deficit effects on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance: metabolic reorganization prior to early stress responses

Czech Academy of Sciences Publication Activity Database

Pinheiro, C.; António, C.; Dobrev, Petre; Vaňková, Radomíra; Wilson, J. C.

2011-01-01

Roč. 62, č. 14 (2011), s. 4965-4974 ISSN 0022-0957 Institutional research plan: CEZ:AV0Z50380511 Keywords : Carbon metabolism * hormone balance * LC-MS Subject RIV: EF - Botanics Impact factor: 5.364, year: 2011

DEPTOR in POMC neurons affects liver metabolism but is dispensable for the regulation of energy balance.

Science.gov (United States)

Caron, Alexandre; Labbé, Sébastien M; Mouchiroud, Mathilde; Huard, Renaud; Lanfray, Damien; Richard, Denis; Laplante, Mathieu

2016-06-01

We have recently demonstrated that specific overexpression of DEP-domain containing mTOR-interacting protein (DEPTOR) in the mediobasal hypothalamus (MBH) protects mice against high-fat diet-induced obesity, revealing DEPTOR as a significant contributor to energy balance regulation. On the basis of evidence that DEPTOR is expressed in the proopiomelanocortin (POMC) neurons of the MBH, the present study aimed to investigate whether these neurons mediate the metabolic effects of DEPTOR. Here, we report that specific DEPTOR overexpression in POMC neurons does not recapitulate any of the phenotypes observed when the protein was overexpressed in the MBH. Unlike the previous model, mice overexpressing DEPTOR only in POMC neurons 1) did not show differences in feeding behavior, 2) did not exhibit changes in locomotion activity and oxygen consumption, 3) did not show an improvement in systemic glucose metabolism, and 4) were not resistant to high-fat diet-induced obesity. These results support the idea that other neuronal populations are responsible for these phenotypes. Nonetheless, we observed a mild elevation in fasting blood glucose, insulin resistance, and alterations in liver glucose and lipid homeostasis in mice overexpressing DEPTOR in POMC neurons. Taken together, these results show that DEPTOR overexpression in POMC neurons does not affect energy balance regulation but could modulate metabolism through a brain-liver connection. Copyright © 2016 the American Physiological Society.

The Subtle Balance between Lipolysis and Lipogenesis: A Critical Point in Metabolic Homeostasis.

Science.gov (United States)

Saponaro, Chiara; Gaggini, Melania; Carli, Fabrizia; Gastaldelli, Amalia

2015-11-13

Excessive accumulation of lipids can lead to lipotoxicity, cell dysfunction and alteration in metabolic pathways, both in adipose tissue and peripheral organs, like liver, heart, pancreas and muscle. This is now a recognized risk factor for the development of metabolic disorders, such as obesity, diabetes, fatty liver disease (NAFLD), cardiovascular diseases (CVD) and hepatocellular carcinoma (HCC). The causes for lipotoxicity are not only a high fat diet but also excessive lipolysis, adipogenesis and adipose tissue insulin resistance. The aims of this review are to investigate the subtle balances that underlie lipolytic, lipogenic and oxidative pathways, to evaluate critical points and the complexities of these processes and to better understand which are the metabolic derangements resulting from their imbalance, such as type 2 diabetes and non alcoholic fatty liver disease.

Flux Balance Analysis Inspired Bioprocess Upgrading for Lycopene Production by a Metabolically Engineered Strain of Yarrowia lipolytica

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Komi Nambou

2015-12-01

Full Text Available Genome-scale metabolic models embody a significant advantage of systems biology since their applications as metabolic flux simulation models enable predictions for the production of industrially-interesting metabolites. The biotechnological production of lycopene from Yarrowia lipolytica is an emerging scope that has not been fully scrutinized, especially for what concerns cultivation conditions of newly generated engineered strains. In this study, by combining flux balance analysis (FBA and Plackett-Burman design, we screened chemicals for lycopene production from a metabolically engineered strain of Y. lipolytica. Lycopene concentrations of 126 and 242 mg/L were achieved correspondingly from the FBA-independent and the FBA-assisted designed media in fed-batch cultivation mode. Transcriptional studies revealed upregulations of heterologous genes in media designed according to FBA, thus implying the efficiency of model predictions. Our study will potentially support upgraded lycopene and other terpenoids production from existing or prospect bioengineered strains of Y. lipolytica and/or closely related yeast species.

Find_tfSBP: find thermodynamics-feasible and smallest balanced pathways with high yield from large-scale metabolic networks.

Science.gov (United States)

Xu, Zixiang; Sun, Jibin; Wu, Qiaqing; Zhu, Dunming

2017-12-11

Biologically meaningful metabolic pathways are important references in the design of industrial bacterium. At present, constraint-based method is the only way to model and simulate a genome-scale metabolic network under steady-state criteria. Due to the inadequate assumption of the relationship in gene-enzyme-reaction as one-to-one unique association, computational difficulty or ignoring the yield from substrate to product, previous pathway finding approaches can't be effectively applied to find out the high yield pathways that are mass balanced in stoichiometry. In addition, the shortest pathways may not be the pathways with high yield. At the same time, a pathway, which exists in stoichiometry, may not be feasible in thermodynamics. By using mixed integer programming strategy, we put forward an algorithm to identify all the smallest balanced pathways which convert the source compound to the target compound in large-scale metabolic networks. The resulting pathways by our method can finely satisfy the stoichiometric constraints and non-decomposability condition. Especially, the functions of high yield and thermodynamics feasibility have been considered in our approach. This tool is tailored to direct the metabolic engineering practice to enlarge the metabolic potentials of industrial strains by integrating the extensive metabolic network information built from systems biology dataset.

Intestinal Microbiota Contributes to Energy Balance, Metabolic Inflammation, and Insulin Resistance in Obesity

Directory of Open Access Journals (Sweden)

Joseph F. Cavallari

2017-09-01

Full Text Available Obesity is associated with increased risk of developing metabolic diseases such as type 2 diabetes. The origins of obesity are multi-factorial, but ultimately rooted in increased host energy accumulation or retention. The gut microbiota has been implicated in control of host energy balance and nutrient extraction from dietary sources. The microbiota also impacts host immune status and dysbiosis-related inflammation can augment insulin resistance, independently of obesity. Advances in microbial metagenomic analyses and directly manipulating bacterial-host models of obesity have contributed to our understanding of the relationship between gut bacteria and metabolic disease. Foodborne, or drug-mediated perturbations to the gut microbiota can increase metabolic inflammation, insulin resistance, and dysglycemia. There is now some evidence that specific bacterial species can influence obesity and related metabolic defects such as insulin sensitivity. Components of bacteria are sufficient to impact obesity-related changes in metabolism. In fact, different microbial components derived from the bacterial cell wall can increase or decrease insulin resistance. Improving our understanding of the how components of the microbiota alter host metabolism is positioned to aid in the development of dietary interventions, avoiding triggers of dysbiosis, and generating novel therapeutic strategies to combat increasing rates of obesity and diabetes.

Metabolic flux balance analysis and the in silico analysis of Escherichia coli K-12 gene deletions

Directory of Open Access Journals (Sweden)

Edwards Jeremy S

2000-07-01

Full Text Available Abstract Background Genome sequencing and bioinformatics are producing detailed lists of the molecular components contained in many prokaryotic organisms. From this 'parts catalogue' of a microbial cell, in silico representations of integrated metabolic functions can be constructed and analyzed using flux balance analysis (FBA. FBA is particularly well-suited to study metabolic networks based on genomic, biochemical, and strain specific information. Results Herein, we have utilized FBA to interpret and analyze the metabolic capabilities of Escherichia coli. We have computationally mapped the metabolic capabilities of E. coli using FBA and examined the optimal utilization of the E. coli metabolic pathways as a function of environmental variables. We have used an in silico analysis to identify seven gene products of central metabolism (glycolysis, pentose phosphate pathway, TCA cycle, electron transport system essential for aerobic growth of E. coli on glucose minimal media, and 15 gene products essential for anaerobic growth on glucose minimal media. The in silico tpi-, zwf, and pta- mutant strains were examined in more detail by mapping the capabilities of these in silico isogenic strains. Conclusions We found that computational models of E. coli metabolism based on physicochemical constraints can be used to interpret mutant behavior. These in silica results lead to a further understanding of the complex genotype-phenotype relation. Supplementary information: http://gcrg.ucsd.edu/supplementary_data/DeletionAnalysis/main.htm

Kynurenine pathway metabolic balance influences microglia activity: Targeting kynurenine monooxygenase to dampen neuroinflammation.

Science.gov (United States)

Garrison, Allison M; Parrott, Jennifer M; Tuñon, Arnulfo; Delgado, Jennifer; Redus, Laney; O'Connor, Jason C

2018-08-01

Chronic stress or inflammation increases tryptophan metabolism along the kynurenine pathway (KP), and the generation of neuroactive kynurenine metabolites contributes to subsequent depressive-like behaviors. Microglia regulate KP balance by preferentially producing oxidative metabolites, including quinolinic acid. Research has focused on the interplay between cytokines and HPA axis-derived corticosteroids in regulating microglial activity and effects of KP metabolites directly on neurons; however, the potential role that KP metabolites have directly on microglial activity is unknown. Here, murine microglia were stimulated with lipopolysaccharide(LPS). After 6 h, mRNA expression of interleukin(IL)-1β, IL-6, tumor necrosis factor(TNF)-α and inducible nitric oxide synthase(iNOS) was dose-dependently increased along with the rate-limiting enzymes for oxidative KP metabolism, indoleamine-2,3-dioxygenase(IDO)-1 and kynurenine 3-monooxygenase(KMO). By 24 h post-LPS, kynurenine and quinolinic acid in the media was elevated. Inhibiting KMO with Ro 61-8048 during LPS challenge attenuated extracellular nitrite accumulation and expression of KMO and TNF-α in response to LPS. Similarly, primary microglia isolated from KMO -/- mice exhibited a significantly reduced pro-inflammatory response to LPS compared to WT controls. To determine whether the substrate (kynurenine) or end product (quinolinic acid) of KMO-dependent metabolism modulates the LPS response, microglia were treated with increasing concentrations of L-kynurenine or quinolinic acid in combination with LPS or saline. Interestingly, quinolinic acid did not impact the microglial LPS response. However, L-kynurenine had dose-dependent inhibitory effect on the LPS response. These data are the first to show an anti-inflammatory effect of KMO inhibition on microglia during immune challenge and suggest that KP metabolic balance may play a direct role in regulating microglia activity. Published by Elsevier Ltd.

Balance og stofskifte

DEFF Research Database (Denmark)

2011-01-01

Udstilling på Medicinsk Museion. Baseret på bevilling fra Assens Fond. Se mere på http://www.museion.ku.dk/whats-on/exhibitions/balance-and-metabolism/......Udstilling på Medicinsk Museion. Baseret på bevilling fra Assens Fond. Se mere på http://www.museion.ku.dk/whats-on/exhibitions/balance-and-metabolism/...

32P studies into phosphate metabolism of cattle with metabolic acidosis

International Nuclear Information System (INIS)

Lachmann, G.; Pfueller, K.; Bier, H.; Mueller, D.; Rummel, G.

1984-01-01

Phosphorus balance and intraveneous injection of 32 P into three bulls showed that hay diet was followed by excretion of only small amounts of phosphorus in the urine (1.5 g/die), with renal net base excretion being 35 mmol/l. Yet, the amounts of phosphorus excretion in urine were high (16.3 g/die) in conditions of metabolic acidosis due to cereal diet, with renal net acid excretion being 78 mmol/l. No negative balance was observed during three weeks of acidosis, in spite of high phosphaturia, since in cattle with acidosis the increase in renal excretion was offsetted by depression of endogenic fecal phosphorus. Endogenic fecal phosphorus accounted for 43% of phosphorus intake with hay diet but only for 7% with cereal diet. Hence, hyperphosphaturia is ruled out as a cause for the genesis of osteopathies in a condition of metabolic acidosis. (author)

Nitrogen balance of healthy Dutch women before and during pregnancy

NARCIS (Netherlands)

Mojtahedi, M.; Groot, de C.P.G.M.; Boekholt, H.A.; Raaij, van J.M.A.

2002-01-01

Background: Experimental studies including longitudinal nitrogen balance studies could provide insight into protein metabolism in pregnancy. Objective: Our aim was to determine the development of nitrogen balance during pregnancy compared with nitrogen balance before pregnancy in women consuming

Gut microbiota and metabolic syndrome.

Science.gov (United States)

Festi, Davide; Schiumerini, Ramona; Eusebi, Leonardo Henry; Marasco, Giovanni; Taddia, Martina; Colecchia, Antonio

2014-11-21

Gut microbiota exerts a significant role in the pathogenesis of the metabolic syndrome, as confirmed by studies conducted both on humans and animal models. Gut microbial composition and functions are strongly influenced by diet. This complex intestinal "superorganism" seems to affect host metabolic balance modulating energy absorption, gut motility, appetite, glucose and lipid metabolism, as well as hepatic fatty storage. An impairment of the fine balance between gut microbes and host's immune system could culminate in the intestinal translocation of bacterial fragments and the development of "metabolic endotoxemia", leading to systemic inflammation and insulin resistance. Diet induced weight-loss and bariatric surgery promote significant changes of gut microbial composition, that seem to affect the success, or the inefficacy, of treatment strategies. Manipulation of gut microbiota through the administration of prebiotics or probiotics could reduce intestinal low grade inflammation and improve gut barrier integrity, thus, ameliorating metabolic balance and promoting weight loss. However, further evidence is needed to better understand their clinical impact and therapeutic use.

Comparison of ion balance and nitrogen metabolism in old and young leaves of alkali-stressed rice plants.

Science.gov (United States)

Wang, Huan; Wu, Zhihai; Han, Jiayu; Zheng, Wei; Yang, Chunwu

2012-01-01

Alkali stress is an important agricultural contaminant and has complex effects on plant metabolism. The aim of this study was to investigate whether the alkali stress has different effects on the growth, ion balance, and nitrogen metabolism in old and young leaves of rice plants, and to compare functions of both organs in alkali tolerance. The results showed that alkali stress only produced a small effect on the growth of young leaves, whereas strongly damaged old leaves. Rice protected young leaves from ion harm via the large accumulation of Na(+) and Cl(-) in old leaves. The up-regulation of OsHKT1;1, OsAKT1, OsHAK1, OsHAK7, OsHAK10 and OsHAK16 may contribute to the larger accumulation of Na(+) in old leaves under alkali stress. Alkali stress mightily reduced the NO(3)(-) contents in both organs. As old leaf cells have larger vacuole, under alkali stress these scarce NO(3)(-) was principally stored in old leaves. Accordingly, the expression of OsNRT1;1 and OsNRT1;2 in old leaves was up-regulated by alkali stress, revealing that the two genes might contribute to the accumulation of NO(3)(-) in old leaves. NO(3)(-) deficiency in young leaves under alkali stress might induce the reduction in OsNR1 expression and the subsequent lacking of NH(4)(+), which might be main reason for the larger down-regulation of OsFd-GOGAT and OsGS2 in young leaves. Our results strongly indicated that, during adaptation of rice to alkali stress, young and old leaves have distinct mechanisms of ion balance and nitrogen metabolism regulation. We propose that the comparative studies of young and old tissues may be important for abiotic stress tolerance research.

Redox Balance in Lactobacillus reuteri DSM20016: Roles of Iron-Dependent Alcohol Dehydrogenases in Glucose/ Glycerol Metabolism.

Directory of Open Access Journals (Sweden)

Lu Chen

Full Text Available Lactobacillus reuteri, a heterofermentative bacterium, metabolizes glycerol via a Pdu (propanediol-utilization pathway involving dehydration to 3-hydroxypropionaldehyde (3-HPA followed by reduction to 1,3-propandiol (1,3-PDO with concomitant generation of an oxidized cofactor, NAD+ that is utilized to maintain cofactor balance required for glucose metabolism and even for oxidation of 3-HPA by a Pdu oxidative branch to 3-hydroxypropionic acid (3-HP. The Pdu pathway is operative inside Pdu microcompartment that encapsulates different enzymes and cofactors involved in metabolizing glycerol or 1,2-propanediol, and protects the cells from the toxic effect of the aldehyde intermediate. Since L. reuteri excretes high amounts of 3-HPA outside the microcompartment, the organism is likely to have alternative alcohol dehydrogenase(s in the cytoplasm for transformation of the aldehyde. In this study, diversity of alcohol dehydrogenases in Lactobacillus species was investigated with a focus on L. reuteri. Nine ADH enzymes were found in L. reuteri DSM20016, out of which 3 (PduQ, ADH6 and ADH7 belong to the group of iron-dependent enzymes that are known to transform aldehydes/ketones to alcohols. L. reuteri mutants were generated in which the three ADHs were deleted individually. The lagging growth phenotype of these deletion mutants revealed that limited NAD+/NADH recycling could be restricting their growth in the absence of ADHs. Notably, it was demonstrated that PduQ is more active in generating NAD+ during glycerol metabolism within the microcompartment by resting cells, while ADH7 functions to balance NAD+/NADH by converting 3-HPA to 1,3-PDO outside the microcompartment in the growing cells. Moreover, evaluation of ADH6 deletion mutant showed strong decrease in ethanol level, supporting the role of this bifuctional alcohol/aldehyde dehydrogenase in ethanol production. To the best of our knowledge, this is the first report revealing both internal and

The use of Total Body In Vivo Neutron Activation Analysis (TBIVNAA) in balance studies in rodents

International Nuclear Information System (INIS)

Smith, D.A.; Lindsay, R.L.; Anderson, J.

1976-01-01

In the investigation of animals subject to alteration in diet or other metabolic experiments, the measurements of change in body calcium, phosphorus, sodium and nitrogen are of considerable interest. However, conventional balance studies are tedious and subject to both random and cumulative error, necessitating as they do accurate estimates of dietary intake and faecal and urinary output. The object of the present study was to determine the usefulness of total body in vivo neutron activation analysis, used at the beginning and end of the experimental period, as an alternative to conventional balance techniques. (orig.) [de

Contribution to the study of calcium metabolism in the deficiency of testosterone

International Nuclear Information System (INIS)

Correa, S.M.J.C.

1980-01-01

Kinetic parameters of calcium mobilization in rats were determined to estimate the role of testosterone in the metabolism of this ion. Calcium multicompartimental theory was combined to and used in measurements of metabolic balance (for 45 CaCl 2 or 40 CaCl 2 ). Three groups of 60 day old rats were used: G I-control; G II-castrated; G III-castrated and treated with testosterone propionate. Data were obtained from measurements of Ca ++ in samples of plasma, feces and urine. Balance studies suggest that calcium level in blood plasma remained constant in all groups, the increase of bone reabsorption in groups II and III being counterbalanced by the elevation of the urinary excrection. This result implies the equilibrium occurring at renal level. Intestinal calcium absorption remained the same in the three groups of animals, indicating that testosterone has no consistent effect at intestinal level. The increase of total calcium in feces of groups II and III arises from a great endogenous secretion. A significant negative balance of calcium was also observed in these groups. This fact permits the conclusion that in the absence of testosterone the organism doesn't retain calcium efficiently. (M.A.) [pt

The energy cost for balance control during upright standing

NARCIS (Netherlands)

Houdijk, J.H.P.; Fickert, R.; van Velzen, J.; van Bennekom, C.A.M.

2009-01-01

The aim of this study was to investigate whether balance control during a static upright standing task with and without balance perturbations elicits a significant and meaningful metabolic energy demand and to test whether this energy demand correlates with conventional posturography measures for

A Simplified Model of Human Alcohol Metabolism That Integrates Biotechnology and Human Health into a Mass Balance Team Project

Science.gov (United States)

Yang, Allen H. J.; Dimiduk, Kathryn; Daniel, Susan

2011-01-01

We present a simplified human alcohol metabolism model for a mass balance team project. Students explore aspects of engineering in biotechnology: designing/modeling biological systems, testing the design/model, evaluating new conditions, and exploring cutting-edge "lab-on-a-chip" research. This project highlights chemical engineering's impact on…

Effect of amino acid supplementation on titer and glycosylation distribution in hybridoma cell cultures-Systems biology-based interpretation using genome-scale metabolic flux balance model and multivariate data analysis.

Science.gov (United States)

Reimonn, Thomas M; Park, Seo-Young; Agarabi, Cyrus D; Brorson, Kurt A; Yoon, Seongkyu

2016-09-01

Genome-scale flux balance analysis (FBA) is a powerful systems biology tool to characterize intracellular reaction fluxes during cell cultures. FBA estimates intracellular reaction rates by optimizing an objective function, subject to the constraints of a metabolic model and media uptake/excretion rates. A dynamic extension to FBA, dynamic flux balance analysis (DFBA), can calculate intracellular reaction fluxes as they change during cell cultures. In a previous study by Read et al. (2013), a series of informed amino acid supplementation experiments were performed on twelve parallel murine hybridoma cell cultures, and this data was leveraged for further analysis (Read et al., Biotechnol Prog. 2013;29:745-753). In order to understand the effects of media changes on the model murine hybridoma cell line, a systems biology approach is applied in the current study. Dynamic flux balance analysis was performed using a genome-scale mouse metabolic model, and multivariate data analysis was used for interpretation. The calculated reaction fluxes were examined using partial least squares and partial least squares discriminant analysis. The results indicate media supplementation increases product yield because it raises nutrient levels extending the growth phase, and the increased cell density allows for greater culture performance. At the same time, the directed supplementation does not change the overall metabolism of the cells. This supports the conclusion that product quality, as measured by glycoform assays, remains unchanged because the metabolism remains in a similar state. Additionally, the DFBA shows that metabolic state varies more at the beginning of the culture but less by the middle of the growth phase, possibly due to stress on the cells during inoculation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1163-1173, 2016. © 2016 American Institute of Chemical Engineers.

A method for accounting for maintenance costs in flux balance analysis improves the prediction of plant cell metabolic phenotypes under stress conditions.

Science.gov (United States)

Cheung, C Y Maurice; Williams, Thomas C R; Poolman, Mark G; Fell, David A; Ratcliffe, R George; Sweetlove, Lee J

2013-09-01

Flux balance models of metabolism generally utilize synthesis of biomass as the main determinant of intracellular fluxes. However, the biomass constraint alone is not sufficient to predict realistic fluxes in central heterotrophic metabolism of plant cells because of the major demand on the energy budget due to transport costs and cell maintenance. This major limitation can be addressed by incorporating transport steps into the metabolic model and by implementing a procedure that uses Pareto optimality analysis to explore the trade-off between ATP and NADPH production for maintenance. This leads to a method for predicting cell maintenance costs on the basis of the measured flux ratio between the oxidative steps of the oxidative pentose phosphate pathway and glycolysis. We show that accounting for transport and maintenance costs substantially improves the accuracy of fluxes predicted from a flux balance model of heterotrophic Arabidopsis cells in culture, irrespective of the objective function used in the analysis. Moreover, when the new method was applied to cells under control, elevated temperature and hyper-osmotic conditions, only elevated temperature led to a substantial increase in cell maintenance costs. It is concluded that the hyper-osmotic conditions tested did not impose a metabolic stress, in as much as the metabolic network is not forced to devote more resources to cell maintenance. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Effect of A One-Week Balanced Diet on Expression of Genes Related to Zinc Metabolism and Inflammation in Type 2 Diabetic Patients.

Science.gov (United States)

Lais, Lucia Leite; de Lima Vale, Sancha Helena; Xavier, Camila Alves; de Araujo Silva, Alfredo; Aydemir, Tolunay Beker; Cousins, Robert J

2016-01-01

To evaluate the effect of diet on metabolic control and zinc metabolism in patients with type 2 diabetes mellitus (T2DM). One-week balanced diet was provided to 10 Brazilians patients with T2DM. Nutritional assessment, laboratorial parameters and expression of zinc transporter and inflammatory genes in peripheral blood mononuclear cells (PBMC) were performed. Healthy non-diabetic subjects of the same demographic were recruited to provide baseline data. Diabetic patients had higher body mass index and greater fasting plasma glucose, plasma tumor necrosis factor α (TNFα) and plasma interleukin 6 (IL6) levels compared with healthy subjects. In addition, the expression of transporters 4 (ZnT4) mRNA was lower and IL6 mRNA was higher in PBMC of these diabetic patients than in healthy subject. One week after a balanced diet was provided, fasting plasma glucose decreased significantly as did TNFα, IL6 and Metallothionein 1 (MT1) mRNAs. No change was observed in zinc transporter expression in PBMC after the dietary intervention. A healthy eating pattern maintained for one week was able to improve metabolic control of diabetic patients by lowering fasting plasma glucose. This metabolic control may be related to down-regulation of zinc-related transcripts from PBMCs, as TNFα, IL6 and MT1 mRNA.

Nutritional and metabolic changes due the abdominal radiation: experimental study

International Nuclear Information System (INIS)

Mucerino, Donato R.; Waitzberg, Dan L.; Campos, Fabio G. de; Melo Auricchio, Maria T. de; Gama-Rodrigues, Joaquim J.; Lima-Goncalves, Ernesto L.

1995-01-01

In this study the effects on nutritional status and energetic metabolism due the abdominal irradiation were analysed. Adult male wistar rats (48), were divided in two groups Control (C) and radiated (R). The rats were maintained all time in metabolic cages. the study was done in two periods: period 1 begun at 0 day, were rats adapted to cages and oral diet, had food and water ad libitum. At the day four indirect calorimetric measurements were performed (calorimetry 1). At period 2, group R rats abdominal radiation at a 300 c Gy/day rate, for 5 consecutive days, and group C started a pair-feeding process linked individually to R rats and suffered application to simulated-irradiation. Two other calorimetric measurements (II,III) were performing during period 2. After radiation the last calorimetry was performed (IV). At sacrifice (day 14) blood was collected for determination of hemoglobin, hematocrit, albumin and transferrin. There were no statistical differences among groups C and R during period 1 (p < 0.05). Great reduction in food intake and weight variation were found in period 2, but weight loss was significantly higher in R rats. Nitrogen balance decrease in period 2, but without difference among the groups (p < 0.05). Serum albumin was significantly lower in R rats. Respiratory quotient decreased in both groups during period 2, but rats kept it lower (p < 0.05). The energy expenditure level decreased after radiation in group R. During period 2 total substrate oxidation decreased in R rats. Radiation decrease glucose and protein oxidation. In conclusion, in this study's conditions, radiation produced malnutrition by reducing food intake by bringing weight loss, hypoalbuminemia and decrease nitrogen balance. Radiation was also responsible for a reduction of metabolism, by promoting the fall of energy expenditure. These changes are not only due the anorexia, undoubtful a main factor. (author)

Dietary Energy Source in Dairy Cows in Early Lactation: Metabolites and Metabolic Hormones

NARCIS (Netherlands)

Knegsel, van A.T.M.; Brand, van den H.; Graat, E.A.M.; Dijkstra, J.; Jorritsma, R.; Decuypere, M.P.; Tamminga, S.; Kemp, B.

2007-01-01

Negative energy balance-related metabolic disorders suggest that the balance between available lipogenic and glucogenic nutrients is important. The objectives of this study were to compare the effects of a glucogenic or a lipogenic diet on liver triacylglycerides (TAG), metabolites, and metabolic

Intermittent fasting, energy balance and associated health outcomes in adults: study protocol for a randomised controlled trial.

Science.gov (United States)

Templeman, Iain; Thompson, Dylan; Gonzalez, Javier; Walhin, Jean-Philippe; Reeves, Sue; Rogers, Peter J; Brunstrom, Jeffrey M; Karagounis, Leonidas G; Tsintzas, Kostas; Betts, James A

2018-02-02

Prior studies have shown that intermittent fasting is capable of producing improvements in body weight and fasted health markers. However, the extent to which intermittent fasting incurs compensatory changes in the components of energy balance and its impact on postprandial metabolism are yet to be ascertained. A total of 30-36 lean participants and 30-36 overweight/obese participants will be recruited to provide two separate study groups who will undergo the same protocol. Following an initial assessment of basic anthropometry and key health markers, measurements of habitual energy intake (weighed food and fluid intake) and physical activity energy expenditure (combined heart rate and accelerometry) will be obtained over 4 weeks under conditions of energy balance. Participants will then be randomly allocated to one of three experimental conditions for 20 days, namely (1) daily calorie restriction (reduce habitual daily energy intake by 25%), (2) intermittent fasting with calorie restriction (alternate between 24-hour periods of fasting and feeding to 150% of habitual daily energy intake), (3) intermittent fasting without calorie restriction (alternate between 24-hour periods of fasting and feeding to 200% of habitual daily energy intake). In addition to continued monitoring of energy intake and physical activity during the intervention, participants will report for laboratory-based assessments of various metabolic parameters both before and after the intervention. Specifically, fasting and postprandial measurements of resting metabolic rate, substrate oxidation, appetite, food preference, and plasma concentrations of key metabolites and hormones will be made, in addition to subcutaneous abdominal adipose tissue biopsies in the fasted state and an assessment of body composition via dual-energy x-ray absorptiometry. Comparing observed changes in these measures across the three intervention arms in each group will establish the impact of intermittent fasting on

Variations in Urine Calcium Isotope: Composition Reflect Changes in Bone Mineral Balance in Humans

Science.gov (United States)

Skulan, Joseph; Anbar, Ariel; Bullen, Thomas; Puzas, J. Edward; Shackelford, Linda; Smith, Scott M.

2004-01-01

Changes in bone mineral balance cause rapid and systematic changes in the calcium isotope composition of human urine. Urine from subjects in a 17 week bed rest study was analyzed for calcium isotopic composition. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism indicates the calcium isotope composition of urine reflects changes in bone mineral balance. Urine calcium isotope composition probably is affected by both bone metabolism and renal processes. Calcium isotope. analysis of urine and other tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.

From metabolism to ecology: cross-feeding interactions shape the balance between polymicrobial conflict and mutualism.

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Estrela, Sylvie; Trisos, Christopher H; Brown, Sam P

2012-11-01

Polymicrobial interactions are widespread in nature and play a major role in maintaining human health and ecosystems. Whenever one organism uses metabolites produced by another organism as energy or nutrient sources, it is called cross-feeding. The ecological outcomes of cross-feeding interactions are poorly understood and potentially diverse: mutualism, competition, exploitation, or commensalism. A major reason for this uncertainty is the lack of theoretical approaches linking microbial metabolism to microbial ecology. To address this issue, we explore the dynamics of a one-way interspecific cross-feeding interaction in which food can be traded for a service (detoxification). Our results show that diverse ecological interactions (competition, mutualism, exploitation) can emerge from this simple cross-feeding interaction and can be predicted by the metabolic, demographic, and environmental parameters that govern the balance of the costs and benefits of association. In particular, our model predicts stronger mutualism for intermediate by-product toxicity because the resource-service exchange is constrained to the service being neither too vital (high toxicity impairs resource provision) nor dispensable (low toxicity reduces need for service). These results support the idea that bridging microbial ecology and metabolism is a critical step toward a better understanding of the factors governing the emergence and dynamics of polymicrobial interactions.

Uncertainty quantification in flux balance analysis of spatially lumped and distributed models of neuron-astrocyte metabolism.

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Calvetti, Daniela; Cheng, Yougan; Somersalo, Erkki

2016-12-01

Identifying feasible steady state solutions of a brain energy metabolism model is an inverse problem that allows infinitely many solutions. The characterization of the non-uniqueness, or the uncertainty quantification of the flux balance analysis, is tantamount to identifying the degrees of freedom of the solution. The degrees of freedom of multi-compartment mathematical models for energy metabolism of a neuron-astrocyte complex may offer a key to understand the different ways in which the energetic needs of the brain are met. In this paper we study the uncertainty in the solution, using techniques of linear algebra to identify the degrees of freedom in a lumped model, and Markov chain Monte Carlo methods in its extension to a spatially distributed case. The interpretation of the degrees of freedom in metabolic terms, more specifically, glucose and oxygen partitioning, is then leveraged to derive constraints on the free parameters to guarantee that the model is energetically feasible. We demonstrate how the model can be used to estimate the stoichiometric energy needs of the cells as well as the household energy based on the measured oxidative cerebral metabolic rate of glucose and glutamate cycling. Moreover, our analysis shows that in the lumped model the net direction of lactate dehydrogenase (LDH) in the cells can be deduced from the glucose partitioning between the compartments. The extension of the lumped model to a spatially distributed multi-compartment setting that includes diffusion fluxes from capillary to tissue increases the number of degrees of freedom, requiring the use of statistical sampling techniques. The analysis of the distributed model reveals that some of the conclusions valid for the spatially lumped model, e.g., concerning the LDH activity and glucose partitioning, may no longer hold.

Modelling of the metabolism of Zymomonas mobilis

Energy Technology Data Exchange (ETDEWEB)

Posten, C; Thoma, M

1986-01-01

In order to optimize fermentations with respect to media, reactor configuration, and control a structured model of the metabolism of Zymononas mobilis has been developed. The model is based on structure of metabolism, rate limiting steps, energy balance and metabolic elemental balances. A three-fold effect of ethanol has been observed concerning substrate-turnover, ammonia uptake and energy consumption. In addition to the metabolic view a structured cell-membrane-model should be considered.

Effect of energy balance profiles on metabolic and reproductive response in Holstein and Swedish Red cows.

Science.gov (United States)

Ntallaris, T; Humblot, P; Båge, R; Sjunnesson, Y; Dupont, J; Berglund, B

2017-03-01

This study examined the effect of two feeding levels during the antepartum and postpartum period on reproductive performance and blood metabolites (glucose, non-esterified fatty acids (NEFA), insulin) in primiparous Holstein and Swedish Red (SRB) cows, in order to identify possible differences in the way these breeds respond to negative energy balance after calving. A total of 44 cows (22 Holstein, 22 SRB) kept in a loose housing system were included in the study. The control group (HE, n = 23) was fed a diet for high-producing cows (target 35 kg/d energycorrected milk, ECM). A lower feeding intensity (LE, n = 21) was achieved by giving -50% concentrate to target 25 kg/d ECM. Diets were implemented 30 days before expected calving and the cows were monitored for 120 days postpartum. Milk yield and composition, dry matter intake (DMI), live body weight and body condition score (BCS) were assessed to calculate the weekly energy balance (residual feed intake). Blood sampling started before diet implementation and was repeated every 2 weeks until Day 60 postpartum and then once monthly until Day 120. Plasma was kept at -20 °C until analysis for glucose, insulin and NEFA concentrations. Mixed linear models were used to analyse data (SAS 9.3; PROC MIXED). Holstein cows had lower mean energy balance than SRB cows (-4.7 ± 1.4 and -0.9 ± 1.4 MJ, respectively; p = 0.05). SRB cows had higher (pcows (2.7 ± 0.1) and also higher plasma glucose concentrations from Day -30 to Day 120 relative to parturition (4.1 ± 0.1 and 4.2 ± 0.1 log ; mg/100 ml, respectively; p cows than in Holsteins at Day -14 before calving, indicating higher mobilisation of lipid from adipose tissue already before calving. In contrast, Holstein cows had higher NEFA at Day 14 postpartum than SRB cows (p cows prioritise milk production to a larger extent than SRB cows, resulting in a less balanced metabolic profile. Copyright © 2016 Elsevier Inc. All rights reserved.

Genome-scale modeling for metabolic engineering.

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Simeonidis, Evangelos; Price, Nathan D

2015-03-01

We focus on the application of constraint-based methodologies and, more specifically, flux balance analysis in the field of metabolic engineering, and enumerate recent developments and successes of the field. We also review computational frameworks that have been developed with the express purpose of automatically selecting optimal gene deletions for achieving improved production of a chemical of interest. The application of flux balance analysis methods in rational metabolic engineering requires a metabolic network reconstruction and a corresponding in silico metabolic model for the microorganism in question. For this reason, we additionally present a brief overview of automated reconstruction techniques. Finally, we emphasize the importance of integrating metabolic networks with regulatory information-an area which we expect will become increasingly important for metabolic engineering-and present recent developments in the field of metabolic and regulatory integration.

Shift work and its association with metabolic disorders

OpenAIRE

Brum, Maria Carlota Borba; Dantas Filho, Fábio Fernandes; Schnorr, Claudia Carolina; Bottega, Gustavo Borchardt; Rodrigues, Ticiana da Costa

2015-01-01

Although the health burden of shift work has not been extensively studied, evidence suggests that it may affect the metabolic balance and cause obesity and other metabolic disorders. Sleep deprivation, circadian desynchronization and behavioral changes in diet and physical activity are among the most commonly mentioned factors in studies of the association between night work and metabolic disorders. Individual adaptation to night work depends greatly on personal factors such as family and soc...

Modeling of Zymomonas mobilis central metabolism for novel metabolic engineering strategies.

Science.gov (United States)

Kalnenieks, Uldis; Pentjuss, Agris; Rutkis, Reinis; Stalidzans, Egils; Fell, David A

2014-01-01

Mathematical modeling of metabolism is essential for rational metabolic engineering. The present work focuses on several types of modeling approach to quantitative understanding of central metabolic network and energetics in the bioethanol-producing bacterium Zymomonas mobilis. Combined use of Flux Balance, Elementary Flux Mode, and thermodynamic analysis of its central metabolism, together with dynamic modeling of the core catabolic pathways, can help to design novel substrate and product pathways by systematically analyzing the solution space for metabolic engineering, and yields insights into the function of metabolic network, hardly achievable without applying modeling tools.

Metabolic, endocrine, and related bone diseases

International Nuclear Information System (INIS)

Rogers, L.F.

1987-01-01

Bone is living tissue, and old bone is constantly removed and replaced with new bone. Normally this exchange is in balance, and the mineral content remains relatively constant. This balance may be disturbed as a result of certain metabolic and endocrinologic disorders. The term dystrophy, referring to a disturbance of nutrition, is applied to metabolic and endocrine bone diseases and should be distinguished from the term dysplasia, referring to a disturbance of bone growth. The two terms are easily confused but are not interchangeable. Metabolic bone disease is caused by endocrine imbalance, vitamin deficiency or excess, and other disturbances in bone metabolism leading to osteoporosis and osteomalacia

Ca-48 metabolism studies

International Nuclear Information System (INIS)

Van der Merwe, D.G.

1987-03-01

Calcium metabolism has been studied in depth physiologically and is a relatively well-understood element in biochemistry and medicine. There is still only restricted knowledge of the metabolic fate of calcium in normal and abnormal paediatric subjects. The latter is partially owing to inadequate techniques for tracing and modelling calcium pathways in children. The advent of radioactive tracers has unquestionably enhanced medical research and improved the quality of many metabolic studies. The present study was aimed at the development, promotion and justification of a new tracer technique using the stable isotope, calcium-48. The obvious advantages of such a technique are its harmlessness tothe subject, its applicability to both short- and long-term studies as well as its usefulness to the study for which it was originally motivated, viz research defining the actual relationship between a calcium-deficient diet and the occurrence of rickets in rural Black children in South Africa. Exploratory instrumental analyses were performed specifically with serum samples. This proved successful enough to develop a less specific pre-concentration technique which improved the sensitivity and reduces the cost of doing calcium-48 metabolism studies. The results of a simple metabolic study are presented whereby the scope of the technique is demonstrated in a real situation. The possibilities and limitations of double-isotope metabolic studies are discussed, particularly with regard to strontium as the second tracer

Pulmonary metabolism of foreign compounds: Its role in metabolic activation

International Nuclear Information System (INIS)

Cohen, G.M.

1990-01-01

The lung has the potential of metabolizing many foreign chemicals to a vast array of metabolites with different pharmacological and toxicological properties. Because many chemicals require metabolic activation in order to exert their toxicity, the cellular distribution of the drug-metabolizing enzymes in a heterogeneous tissue, such as the lung, and the balance of metabolic activation and deactivation pathways in any particular cell are key factors in determining the cellular specificity of many pulmonary toxins. Environmental factors such as air pollution, cigarette smoking, and diet markedly affect the pulmonary metabolism of some chemicals and, thereby, possibly affect their toxicity

Elucidation of new condition-dependent roles for fructose-1,6-bisphosphatase linked to cofactor balances.

Directory of Open Access Journals (Sweden)

Du Toit W P Schabort

Full Text Available The cofactor balances in metabolism is of paramount importance in the design of a metabolic engineering strategy and understanding the regulation of metabolism in general. ATP, NAD+ and NADP+ balances are central players linking the various fluxes in central metabolism as well as biomass formation. NADP+ is especially important in the metabolic engineering of yeasts for xylose fermentation, since NADPH is required by most yeasts in the initial step of xylose utilisation, including the fast-growing Kluyveromyces marxianus. In this simulation study of yeast metabolism, the complex interplay between these cofactors was investigated; in particular, how they may affect the possible roles of fructose-1,6-bisphosphatase, the pentose phosphate pathway, glycerol production and the pyruvate dehydrogenase bypass. Using flux balance analysis, it was found that the potential role of fructose-1,6-bisphosphatase was highly dependent on the cofactor specificity of the oxidative pentose phosphate pathway and on the carbon source. Additionally, the excessive production of ATP under certain conditions might be involved in some of the phenomena observed, which may have been overlooked to date. Based on these findings, a strategy is proposed for the metabolic engineering of a future xylose-fermenting yeast for biofuel production.

Exploration of Energy Metabolism in the Mouse Using Indirect Calorimetry: Measurement of Daily Energy Expenditure (DEE) and Basal Metabolic Rate (BMR).

Science.gov (United States)

Meyer, Carola W; Reitmeir, Peter; Tschöp, Matthias H

2015-09-01

Current comprehensive mouse metabolic phenotyping involves studying energy balance in cohorts of mice via indirect calorimetry, which determines heat release from changes in respiratory air composition. Here, we describe the measurement of daily energy expenditure (DEE) and basal metabolic rate (BMR) in mice. These well-defined metabolic descriptors serve as meaningful first-line read-outs for metabolic phenotyping and should be reported when exploring energy expenditure in mice. For further guidance, the issue of appropriate sample sizes and the frequency of sampling of metabolic measurements is also discussed. Copyright © 2015 John Wiley & Sons, Inc.

A metabolic nitrogen balance study for 40 d and evaluation of the menstrual cycle on protein requirement in young Nigerian women.

Science.gov (United States)

Egun, G N; Atinmo, T

1993-09-01

A long-term N balance study was carried out to determine the adequacy of an estimated protein requirement level recommended for young healthy Nigerian women and the effect of the menstrual cycle on the requirement. Eleven healthy young women, 25 (SD 2.6) years, were fed on a diet providing 0.6 g protein (N x 6.25)/kg per d and an average energy intake of 0.17 (SD 0.012) MJ/kg per d. Urine, faeces, sweat and menstrual fluids were collected for estimation of N balance. Menstrual N loss varied among individuals ranging from 46 to 124 mg N/d with an average of 89 (SD 21.8) mg N/d. Individual N balance was found to vary according to the day of the menstrual cycle. Positive N balances were recorded at about ovulation while negative balances were observed just before the onset of menstruation. The average N balance ranged from +8.49 (SD 5.64) to -430 (SD 7.84) mg N/kg per d. Nevertheless, an overall cumulative positive N balance of +5.7 (SD 6.98) mg N/kg per d which did not change significantly with time was observed for the last 5 d of two consecutive 20 d diet periods, although three subjects were in negative N balance. Blood biochemical measurements were stable except for one subject who had elevated serum aspartate aminotransferase (EC 2.6.1.1) levels. These findings suggest that our estimate of protein requirements was sufficient to achieve N balance equilibrium in a majority (70%) of young women. However, to satisfy 97.5% of the population, slight adjustments might be necessary in the energy intake since subjects who were in cumulative negative N balance also lost weight.

Mass balance, metabolic disposition, and pharmacokinetics of a single oral dose of regorafenib in healthy human subjects.

Science.gov (United States)

Gerisch, Michael; Hafner, Frank-Thorsten; Lang, Dieter; Radtke, Martin; Diefenbach, Konstanze; Cleton, Adriaan; Lettieri, John

2018-01-01

To evaluate the mass balance, metabolic disposition, and pharmacokinetics of a single dose of regorafenib in healthy volunteers. In addition, in vitro metabolism of regorafenib in human hepatocytes was investigated. Four healthy male subjects received one 120 mg oral dose of regorafenib containing approximately 100 µCi (3.7 MBq) [ 14 C]regorafenib. Plasma concentrations of parent drug were derived from HPLC-MS/MS analysis and total radioactivity from liquid scintillation counting (LSC). Radiocarbon analyses used HPLC with fraction collection followed by LSC for all urine samples, plasma, and fecal homogenate extracts. For the in vitro study, [ 14 C]regorafenib was incubated with human hepatocytes and analyzed using HPLC-LSC and HPLC-HRMS/MS. Regorafenib was the major component in plasma, while metabolite M-2 (pyridine N-oxide) was the most prominent metabolite. Metabolites M-5 (demethylated pyridine N-oxide) and M-7 (N-glucuronide) were identified as minor plasma components. The mean concentration of total radioactivity in plasma/whole blood appeared to plateau at 1-4 h and again at 6-24 h post-dose. In total, 90.5% of administered radioactivity was recovered in the excreta within a collection interval of 12 days, most of which (71.2%) was eliminated in feces, while excretion via urine accounted for 19.3%. Regorafenib (47.2%) was the most prominent component in feces and was not excreted into urine. Excreted metabolites resulted from oxidative metabolism and glucuronidation. Regorafenib was eliminated predominantly in feces as well as by hepatic biotransformation. The multiple biotransformation pathways of regorafenib decrease the risk of pharmacokinetic drug-drug interactions.

Calcium Balance in Chronic Kidney Disease.

Science.gov (United States)

Hill Gallant, Kathleen M; Spiegel, David M

2017-06-01

The kidneys play a critical role in the balance between the internal milieu and external environment. Kidney failure is known to disrupt a number of homeostatic mechanisms that control serum calcium and normal bone metabolism. However, our understanding of calcium balance throughout the stages of chronic kidney disease is limited and the concept of balance itself, especially with a cation as complex as calcium, is often misunderstood. Both negative and positive calcium balance have important implications in patients with chronic kidney disease, where negative balance may increase risk of osteoporosis and fracture and positive balance may increase risk of vascular calcification and cardiovascular events. Here, we examine the state of current knowledge about calcium balance in adults throughout the stages of chronic kidney disease and discuss recommendations for clinical strategies to maintain balance as well as future research needs in this area. Recent calcium balance studies in adult patients with chronic kidney disease show that neutral calcium balance is achieved with calcium intake near the recommended daily allowance. Increases in calcium through diet or supplements cause high positive calcium balance, which may put patients at risk for vascular calcification. However, heterogeneity in calcium balance exists among these patients. Given the available calcium balance data in this population, it appears clinically prudent to aim for recommended calcium intakes around 1000 mg/day to achieve neutral calcium balance and avoid adverse effects of either negative or positive calcium balance. Assessment of patients' dietary calcium intake could further equip clinicians to make individualized recommendations for meeting recommended intakes.

Non-stationary (13)C-metabolic flux ratio analysis.

Science.gov (United States)

Hörl, Manuel; Schnidder, Julian; Sauer, Uwe; Zamboni, Nicola

2013-12-01

(13)C-metabolic flux analysis ((13)C-MFA) has become a key method for metabolic engineering and systems biology. In the most common methodology, fluxes are calculated by global isotopomer balancing and iterative fitting to stationary (13)C-labeling data. This approach requires a closed carbon balance, long-lasting metabolic steady state, and the detection of (13)C-patterns in a large number of metabolites. These restrictions mostly reduced the application of (13)C-MFA to the central carbon metabolism of well-studied model organisms grown in minimal media with a single carbon source. Here we introduce non-stationary (13)C-metabolic flux ratio analysis as a novel method for (13)C-MFA to allow estimating local, relative fluxes from ultra-short (13)C-labeling experiments and without the need for global isotopomer balancing. The approach relies on the acquisition of non-stationary (13)C-labeling data exclusively for metabolites in the proximity of a node of converging fluxes and a local parameter estimation with a system of ordinary differential equations. We developed a generalized workflow that takes into account reaction types and the availability of mass spectrometric data on molecular ions or fragments for data processing, modeling, parameter and error estimation. We demonstrated the approach by analyzing three key nodes of converging fluxes in central metabolism of Bacillus subtilis. We obtained flux estimates that are in agreement with published results obtained from steady state experiments, but reduced the duration of the necessary (13)C-labeling experiment to less than a minute. These results show that our strategy enables to formally estimate relative pathway fluxes on extremely short time scale, neglecting cellular carbon balancing. Hence this approach paves the road to targeted (13)C-MFA in dynamic systems with multiple carbon sources and towards rich media. © 2013 Wiley Periodicals, Inc.

Hypothalamic AMPK and fatty acid metabolism mediate thyroid regulation of energy balance.

Science.gov (United States)

López, Miguel; Varela, Luis; Vázquez, María J; Rodríguez-Cuenca, Sergio; González, Carmen R; Velagapudi, Vidya R; Morgan, Donald A; Schoenmakers, Erik; Agassandian, Khristofor; Lage, Ricardo; Martínez de Morentin, Pablo Blanco; Tovar, Sulay; Nogueiras, Rubén; Carling, David; Lelliott, Christopher; Gallego, Rosalía; Oresic, Matej; Chatterjee, Krishna; Saha, Asish K; Rahmouni, Kamal; Diéguez, Carlos; Vidal-Puig, Antonio

2010-09-01

Thyroid hormones have widespread cellular effects; however it is unclear whether their effects on the central nervous system (CNS) contribute to global energy balance. Here we demonstrate that either whole-body hyperthyroidism or central administration of triiodothyronine (T3) decreases the activity of hypothalamic AMP-activated protein kinase (AMPK), increases sympathetic nervous system (SNS) activity and upregulates thermogenic markers in brown adipose tissue (BAT). Inhibition of the lipogenic pathway in the ventromedial nucleus of the hypothalamus (VMH) prevents CNS-mediated activation of BAT by thyroid hormone and reverses the weight loss associated with hyperthyroidism. Similarly, inhibition of thyroid hormone receptors in the VMH reverses the weight loss associated with hyperthyroidism. This regulatory mechanism depends on AMPK inactivation, as genetic inhibition of this enzyme in the VMH of euthyroid rats induces feeding-independent weight loss and increases expression of thermogenic markers in BAT. These effects are reversed by pharmacological blockade of the SNS. Thus, thyroid hormone-induced modulation of AMPK activity and lipid metabolism in the hypothalamus is a major regulator of whole-body energy homeostasis.

Hypothalamic AMPK and fatty acid metabolism mediate thyroid regulation of energy balance

Science.gov (United States)

López, Miguel; Varela, Luis; Vázquez, María J.; Rodríguez-Cuenca, Sergio; González, Carmen R.; Velagapudi, Vidya R.; Morgan, Donald A.; Schoenmakers, Erik; Agassandian, Khristofor; Lage, Ricardo; de Morentin, Pablo Blanco Martínez; Tovar, Sulay; Nogueiras, Rubén; Carling, David; Lelliott, Christopher; Gallego, Rosalía; Orešič, Matej; Chatterjee, Krishna; Saha, Asish K.; Rahmouni, Kamal; Diéguez, Carlos; Vidal-Puig, Antonio

2010-01-01

Thyroid hormones have widespread cellular effects; however it is unclear whether their effects on the central nervous system (CNS) contribute to global energy balance. Here, we demonstrate that either whole body hyperthyroidism or central administration of triiodothyronine (T3) decreases the activity of hypothalamic AMP-activated protein kinase (AMPK), increases sympathetic nervous system (SNS) activity and upregulates thermogenic markers in brown adipose tissue (BAT). Inhibition of the lipogenic pathway in the ventromedial nucleus of the hypothalamus (VMH) prevents CNS-mediated activation of BAT by thyroid hormone and reverses the weight loss associated with hyperthyroidism. Similarly inhibition of thyroid hormone receptors (TRs) in the VMH reverses the weight loss associated with hyperthyroidism. This regulatory mechanism depends on AMPK inactivation as genetic ablation of this enzyme in the VMH of euthyroid rats induces feeding-independent weight loss and increases expression of thermogenic markers in BAT. These effects are reversed by pharmacological blockade of the SNS. Thus, thyroid-hormone-induced modulation of AMPK activity and lipid metabolism in the hypothalamus is an important regulator of energy homeostasis. PMID:20802499

Effects of circular gait training on balance, balance confidence in patients with stroke: a pilot study.

Science.gov (United States)

Park, Shin-Kyu; Kim, Sung-Jin; Yoon, Tak Yong; Lee, Suk-Min

2018-05-01

[Purpose] This study aimed to investigate the effects of circular gait training on balance and balance confidence in patients with stroke. [Subjects and Methods] Fifteen patients with stroke were randomly divided into either the circular gait training (CGT) group (n=8) or the straight gait training (SGT) group (n=7). Both groups had conventional therapy that adhered to the neurodevelopmental treatment (NDT) approach, for 30 min. In addition, the CGT group performed circular gait training, and the SGT group practiced straight gait training for 30 min. Each intervention was applied for 1 h, 5 days a week, for 2 weeks. Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and Activities-specific Balance Confidence (ABC) scale were used to test balance and balance confidence. [Results] After the intervention, both groups showed significant increases in balance and balance confidence. Significant improvements in the balance of the CGT group compared with the SGT group were observed at post-assessment. [Conclusion] This study showed that circular gait training significantly improves balance in patients with stroke.

Effect of Acute Negative and Positive Energy Balance on Basal Very-Low Density Lipoprotein Triglyceride Metabolism in Women

Science.gov (United States)

Bellou, Elena; Maraki, Maria; Magkos, Faidon; Botonaki, Helena; Panagiotakos, Demosthenes B.; Kavouras, Stavros A.; Sidossis, Labros S.

2013-01-01

Background Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG) concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known. Objective The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women. Design Ten healthy women (age: 22.0±2.9 years, BMI: 21.2±1.3 kg/m2) underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i) isocaloric feeding (control) ii) hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii) hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition. Results Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037), owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023) and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016). Hypercaloric feeding increased plasma glucose concentration (P = 0.042) but had no effect on VLDL-TG concentration and kinetics compared to the control trial. Conclusion Acute dietary energy deficit (∼3MJ) leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ) does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women. PMID:23533676

Effect of acute negative and positive energy balance on basal very-low density lipoprotein triglyceride metabolism in women.

Directory of Open Access Journals (Sweden)

Elena Bellou

Full Text Available BACKGROUND: Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known. OBJECTIVE: The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women. DESIGN: Ten healthy women (AGE: 22.0±2.9 years, BMI: 21.2±1.3 kg/m(2 underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i isocaloric feeding (control ii hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition. RESULTS: Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037, owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023 and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016. Hypercaloric feeding increased plasma glucose concentration (P = 0.042 but had no effect on VLDL-TG concentration and kinetics compared to the control trial. CONCLUSION: Acute dietary energy deficit (∼3MJ leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women.

Improving metabolic efficiency of the reverse beta-oxidation cycle by balancing redox cofactor requirement.

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Wu, Junjun; Zhang, Xia; Zhou, Peng; Huang, Jiaying; Xia, Xiudong; Li, Wei; Zhou, Ziyu; Chen, Yue; Liu, Yinghao; Dong, Mingsheng

2017-11-01

Previous studies have made many exciting achievements on pushing the functional reversal of beta-oxidation cycle (r-BOX) to more widespread adoption for synthesis of a wide variety of fuels and chemicals. However, the redox cofactor requirement for the efficient operation of r-BOX remains unclear. In this work, the metabolic efficiency of r-BOX for medium-chain fatty acid (C 6 -C 10 , MCFA) production was optimized by redox cofactor engineering. Stoichiometric analysis of the r-BOX pathway and further experimental examination identified NADH as a crucial determinant of r-BOX process yield. Furthermore, the introduction of formate dehydrogenase from Candida boidinii using fermentative inhibitor byproduct formate as a redox NADH sink improved MCFA titer from initial 1.2g/L to 3.1g/L. Moreover, coupling of increasing the supply of acetyl-CoA with NADH to achieve fermentative redox balance enabled product synthesis at maximum titers. To this end, the acetate re-assimilation pathway was further optimized to increase acetyl-CoA availability associated with the new supply of NADH. It was found that the acetyl-CoA synthetase activity and intracellular ATP levels constrained the activity of acetate re-assimilation pathway, and 4.7g/L of MCFA titer was finally achieved after alleviating these two limiting factors. To the best of our knowledge, this represented the highest titer reported to date. These results demonstrated that the key constraint of r-BOX was redox imbalance and redox engineering could further unleash the lipogenic potential of this cycle. The redox engineering strategies could be applied to acetyl-CoA-derived products or other bio-products requiring multiple redox cofactors for biosynthesis. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Balanços metabólicos do enxofre em pacientes com leucodistrofia metacromática Metabolic balances of sulfur in patients with metachromatic leucodystrophy

Directory of Open Access Journals (Sweden)

Horacio M. Canelas

1968-12-01

Full Text Available Foram estudados os balanços metabólicos do enxofre em dois pacientes com a forma juvenil da leucodistrofia metacromática. Foi verificado, em ambos os casos, um balanço positivo desse metaloide, aparentemente não influenciado pelo tipo de dieta (geral ou vegetal. Este resultado está de acordo com a atual concepção patogênica dessa moléstia, que consiste, essencialmente, em uma sulfatidose com diminuição da atividade das sulfatases.The metabolic balances of sulfur in two cases of the late juvenile form of metachromatic leucodystrophy were studied. A positive balance of sulfur was found in both patients, apparently not influenced by the type of diet (either mixed or vegetarian. This finding is in accordance with the current views on the pathogenesis of the disease, namely a sulfatidosis with low sulfatase activity.

Vertigo and metabolic disorders.

Science.gov (United States)

Santos, Maruska D' Aparecida; Bittar, Roseli Saraiva Moreira

2012-01-01

Metabolic disorders are accepted by many authors as being responsible for balance disorders. Because of the importance of metabolic disorders in the field of labyrinthine dysfunction, we decided to assess the prevalence of carbohydrates, lipids and thyroid hormones disorders in our patients with vestibular diseases. The study evaluates the metabolic profile of 325 patients with vertigo who sought the Otolaryngology Department of the University of São Paulo in the Hospital das Clínicas da Universidade de São Paulo. The laboratory tests ordered according to the classical research protocol were: low-density lipoprotein cholesterol fraction, TSH, T3, T4 and fasting blood sugar level. The metabolic disorders found and the ones that were observed in the general population were compared. The high level of low-density lipoprotein cholesterol, the altered levels of thyroid hormones, the higher prevalence of diabetes mellitus were the most significant changes found in the group of study. The higher amount of metabolic disorders in patients with vertigo disease reinforces the hypothesis of its influence on the etiopathogenesis of cochleovestibular symptoms.

How body balance influences political party evaluations. A Wii balance board study.

Directory of Open Access Journals (Sweden)

Katinka eDijkstra

2012-12-01

Full Text Available Embodied cognition research has shown how actions or body positions may affect cognitive processes, such as autobiographical memory retrieval or judgments. The present study examined the role of body balance (to the left or the right in participants on their attributions to political parties. Participants thought they stood upright on a Wii™ Balance Board, while they were actually slightly tilted to the left or the right. Participants then ascribed fairly general political statements to one of ten political parties that are represented in the Dutch House of Representatives. Results showed a significant interaction of congruent leaning direction with left- or right wing party attribution. When the same analyses were performed with the political parties being divided into affiliations to the right, center, and left based on participants’ personal opinions rather than a ruling classification, no effects were found. The study provides evidence that conceptual metaphors are activated by manipulating body balance implicitly. Moreover, people’s judgments may be colored by seemingly trivial circumstances such as standing slightly out of balance.

How body balance influences political party evaluations: a wii balance board study.

Science.gov (United States)

Dijkstra, Katinka; Eerland, Anita; Zijlmans, Josjan; Post, Lysanne S

2012-01-01

Embodied cognition research has shown how actions or body positions may affect cognitive processes, such as autobiographical memory retrieval or judgments. The present study examined the role of body balance (to the left or the right) in participants on their attributions to political parties. Participants thought they stood upright on a Wii(™) Balance Board, while they were actually slightly tilted to the left or the right. Participants then ascribed fairly general political statements to one of 10 political parties that are represented in the Dutch House of Representatives. Results showed a significant interaction of congruent leaning direction with left- or right-wing party attribution. When the same analyses were performed with the political parties being divided into affiliations to the right, center, and left based on participants' personal opinions rather than a ruling classification, no effects were found. The study provides evidence that conceptual metaphors are activated by manipulating body balance implicitly. Moreover, people's judgments may be colored by seemingly trivial circumstances such as standing slightly out of balance.

Regulation of Mitochondrial Function and Cellular Energy Metabolism by Protein Kinase C-λ/ι: A Novel Mode of Balancing Pluripotency

Science.gov (United States)

Mahato, Biraj; Home, Pratik; Rajendran, Ganeshkumar; Paul, Arindam; Saha, Biswarup; Ganguly, Avishek; Ray, Soma; Roy, Nairita; Swerdlow, Russell H.; Paul, Soumen

2014-01-01

Pluripotent stem cells (PSCs) contain functionally immature mitochondria and rely upon high rates of glycolysis for their energy requirements. Thus, altered mitochondrial function and promotion of aerobic glycolysis is key to maintain and induce pluripotency. However, signaling mechanisms that regulate mitochondrial function and reprogram metabolic preferences in self-renewing vs. differentiated PSC populations are poorly understood. Here, using murine embryonic stem cells (ESCs) as a model system, we demonstrate that atypical protein kinase C isoform, PKC lambda/iota (PKCλ/ι), is a key regulator of mitochondrial function in ESCs. Depletion of PKCλ/ι in ESCs maintains their pluripotent state as evident from germline offsprings. Interestingly, loss of PKCλ/ι in ESCs leads to impairment in mitochondrial maturation, organization and a metabolic shift toward glycolysis under differentiating condition. Our mechanistic analyses indicate that a PKCλ/ι-HIF1α-PGC1α axis regulates mitochondrial respiration and balances pluripotency in ESCs. We propose that PKCλ/ι could be a crucial regulator of mitochondrial function and energy metabolism in stem cells and other cellular contexts. PMID:25142417

Mass-Balance Constraints on Nutrient Cycling in Tropical Seagrass Beds

NARCIS (Netherlands)

Erftemeijer, P.L.A.; Middelburg, J.J.

1995-01-01

A relatively simple mass balance model is presented to study the cycling of nutrients (nitrogen and phosphorus) in tropical seagrass beds. The model is based on quantitative data on nutrient availability, seagrass primary production, community oxygen metabolism, seagrass tissue nutrient contents,

Metabolic cartography: experimental quantification of metabolic fluxes from isotopic labelling studies.

Science.gov (United States)

O'Grady, John; Schwender, Jörg; Shachar-Hill, Yair; Morgan, John A

2012-03-01

For the past decade, flux maps have provided researchers with an in-depth perspective on plant metabolism. As a rapidly developing field, significant headway has been made recently in computation, experimentation, and overall understanding of metabolic flux analysis. These advances are particularly applicable to the study of plant metabolism. New dynamic computational methods such as non-stationary metabolic flux analysis are finding their place in the toolbox of metabolic engineering, allowing more organisms to be studied and decreasing the time necessary for experimentation, thereby opening new avenues by which to explore the vast diversity of plant metabolism. Also, improved methods of metabolite detection and measurement have been developed, enabling increasingly greater resolution of flux measurements and the analysis of a greater number of the multitude of plant metabolic pathways. Methods to deconvolute organelle-specific metabolism are employed with increasing effectiveness, elucidating the compartmental specificity inherent in plant metabolism. Advances in metabolite measurements have also enabled new types of experiments, such as the calculation of metabolic fluxes based on (13)CO(2) dynamic labelling data, and will continue to direct plant metabolic engineering. Newly calculated metabolic flux maps reveal surprising and useful information about plant metabolism, guiding future genetic engineering of crops to higher yields. Due to the significant level of complexity in plants, these methods in combination with other systems biology measurements are necessary to guide plant metabolic engineering in the future.

Metabolism and the Control of Cell Fate Decisions and Stem Cell Renewal

Science.gov (United States)

Ito, Kyoko; Ito, Keisuke

2016-01-01

Although the stem cells of various tissues remain in the quiescent state to maintain their undifferentiated state, they also undergo cell divisions as required, and if necessary, even a single stem cell is able to provide for lifelong tissue homeostasis. Stem cell populations are precisely controlled by the balance between their symmetric and asymmetric divisions, with their division patterns determined by whether the daughter cells involved retain their self-renewal capacities. Recent studies have reported that metabolic pathways and the distribution of mitochondria are regulators of the division balance of stem cells and that metabolic defects can shift division balance toward symmetric commitment, which leads to stem cell exhaustion. It has also been observed that in asymmetric division, old mitochondria, which are central metabolic organelles, are segregated to the daughter cell fated to cell differentiation, whereas in symmetric division, young and old mitochondria are equally distributed between both daughter cells. Thus, metabolism and mitochondrial biology play important roles in stem cell fate decisions. As these decisions directly affect tissue homeostasis, understanding their regulatory mechanisms in the context of cellular metabolism is critical. PMID:27482603

Multi-omics approach to study the growth efficiency and amino acid metabolism in Lactococcus lactis at various specific growth rates

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Arike Liisa

2011-02-01

Full Text Available Abstract Background Lactococcus lactis is recognised as a safe (GRAS microorganism and has hence gained interest in numerous biotechnological approaches. As it is fastidious for several amino acids, optimization of processes which involve this organism requires a thorough understanding of its metabolic regulations during multisubstrate growth. Results Using glucose limited continuous cultivations, specific growth rate dependent metabolism of L. lactis including utilization of amino acids was studied based on extracellular metabolome, global transcriptome and proteome analysis. A new growth medium was designed with reduced amino acid concentrations to increase precision of measurements of consumption of amino acids. Consumption patterns were calculated for all 20 amino acids and measured carbon balance showed good fit of the data at all growth rates studied. It was observed that metabolism of L. lactis became more efficient with rising specific growth rate in the range 0.10 - 0.60 h-1, indicated by 30% increase in biomass yield based on glucose consumption, 50% increase in efficiency of nitrogen use for biomass synthesis, and 40% reduction in energy spilling. The latter was realized by decrease in the overall product formation and higher efficiency of incorporation of amino acids into biomass. L. lactis global transcriptome and proteome profiles showed good correlation supporting the general idea of transcription level control of bacterial metabolism, but the data indicated that substrate transport systems together with lower part of glycolysis in L. lactis were presumably under allosteric control. Conclusions The current study demonstrates advantages of the usage of strictly controlled continuous cultivation methods combined with multi-omics approach for quantitative understanding of amino acid and energy metabolism of L. lactis which is a valuable new knowledge for development of balanced growth media, gene manipulations for desired product

The use of radioisotopes and low abundance stable isotopes for the study of bioavailability and the metabolism of iron, zinc and copper

International Nuclear Information System (INIS)

Aggett, P.J.; Fairweather Tait, S.

1994-01-01

The use of whole body counting and imaging with ''area of interest'' counting to monitor the metabolism of zinc in healthy volunteers and patients with coeliac diseases and cirrhosis is described as are studies of interaction between iron and copper. Stable isotopes of iron, copper and zinc have been used to investigate the metabolism of these elements in young infants and have proved useful in assessing the validity of current estimated requirements particularly of iron. Stable isotopes have also been used to improve the classic metabolic balance approach to the study of the homeostasis of zinc in zinc deprived volunteers, and have progressed to studies using plasma kinetic curves of the systemic compartmentation of zinc

Two Phase 1, Open‐Label, Mass Balance Studies to Determine the Pharmacokinetics of 14C‐Labeled Isavuconazonium Sulfate in Healthy Male Volunteers

Science.gov (United States)

Kato, Kota; Hale, Christine; Kowalski, Donna; Lademacher, Christopher; Yamazaki, Takao; Akhtar, Shahzad; Desai, Amit

2017-01-01

Abstract Isavuconazonium sulfate is the water‐soluble prodrug of the active triazole isavuconazole. Two phase 1 studies were conducted to identify the metabolic profile and mass balance of isavuconazole and BAL8728 (inactive cleavage product). Seven subjects in study 1 (isavuconazole mass balance) received a single oral dose of [cyano‐14C]isavuconazonium sulfate corresponding to 200 mg isavuconazole. Six subjects in study 2 (BAL8728 mass balance) received a single intravenous dose of [pyridinylmethyl‐14C]isavuconazonium sulfate corresponding to 75 mg BAL8728. Pharmacokinetic parameters of radioactivity in whole blood and plasma and of isavuconazole and BAL8728 in plasma were assessed. Radioactivity ratio of blood/plasma, percentage of dose, and cumulative percentage of radioactive dose recovered in urine and feces for isavuconazole and BAL8728 were assessed. Metabolic profiling was carried out by high‐performance liquid chromatography and mass spectrometry. Mean plasma isavuconazole pharmacokinetic parameters included apparent clearance (2.3 ± 0.7 L/h), apparent volume of distribution (301.8 ± 105.7 L), and terminal elimination half‐life (99.9 ± 44.6 hours). In study 1, isavuconazole‐derived radioactivity was recovered approximately equally in urine and feces (46.1% and 45.5%, respectively). In study 2, BAL8728‐derived radioactivity was predominantly recovered in urine (96.0%). Isavuconazole (study 1) and M4 (cleavage metabolite of BAL8728; study 2) were the predominant circulating components of radioactivity in plasma. PMID:28750160

Interactions between negative energy balance, metabolic diseases, uterine health and immune response in transition dairy cows.

Science.gov (United States)

Esposito, Giulia; Irons, Pete C; Webb, Edward C; Chapwanya, Aspinas

2014-01-30

The biological cycles of milk production and reproduction determine dairying profitability thus making management decisions dynamic and time-dependent. Diseases also negatively impact on net earnings of a dairy enterprise. Transition cows in particular face the challenge of negative energy balance (NEB) and/or disproportional energy metabolism (fatty liver, ketosis, subacute, acute ruminal acidosis); disturbed mineral utilization (milk fever, sub-clinical hypocalcemia); and perturbed immune function (retained placenta, metritis, mastitis). Consequently NEB and reduced dry matter intake are aggravated. The combined effects of all these challenges are reduced fertility and milk production resulting in diminishing profits. Risk factors such as NEB, inflammation and impairment of the immune response are highly cause-and-effect related. Thus, managing cows during the transition period should be geared toward reducing NEB or feeding specially formulated diets to improve immunity. Given that all cows experience a reduced feed intake and body condition, infection and inflammation of the uterus after calving, there is a need for further research on the immunology of transition dairy cows. Integrative approaches at the molecular, cellular and animal level may unravel the complex interactions between disturbed metabolism and immune function that predispose cows to periparturient diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

Water-tunnel studies of heat balance in swimming mako sharks.

Science.gov (United States)

Bernal, D; Sepulveda, C; Graham, J B

2001-12-01

The mako shark (Isurus oxyrinchus) has specialized vascular networks (retia mirabilia) forming counter-current heat exchangers that allow metabolic heat retention in certain regions of the body, including the aerobic, locomotor red muscle and the viscera. Red muscle, white muscle and stomach temperatures were measured in juvenile (5-13.6 kg) makos swimming steadily in a water tunnel and exposed to stepwise square-wave changes in ambient temperature (T(a)) to estimate the rates of heat transfer and to determine their capacity for the activity-independent control of heat balance. The rates of heat gain of red muscle during warming were significantly higher than the rates of heat loss during cooling, and neither the magnitude of the change in T(a) nor the direction of change in T(a) had a significant effect on red muscle latency time. Our findings for mako red muscle are similar to those recorded for tunas and suggest modulation of retial heat-exchange efficiency as the underlying mechanism controlling heat balance. However, the red muscle temperatures measured in swimming makos (0.3-3 degrees C above T(a)) are cooler than those measured previously in larger decked makos. Also, the finding of non-stable stomach temperatures contrasts with the predicted independence from T(a) recorded in telemetry studies of mako and white sharks. Our studies on live makos provide new evidence that, in addition to the unique convergent morphological properties between makos and tunas, there is a strong functional similarity in the mechanisms used to regulate heat transfer.

Dynamic metabolic flux analysis using B-splines to study the effects of temperature shift on CHO cell metabolism

Directory of Open Access Journals (Sweden)

Verónica S. Martínez

2015-12-01

Full Text Available Metabolic flux analysis (MFA is widely used to estimate intracellular fluxes. Conventional MFA, however, is limited to continuous cultures and the mid-exponential growth phase of batch cultures. Dynamic MFA (DMFA has emerged to characterize time-resolved metabolic fluxes for the entire culture period. Here, the linear DMFA approach was extended using B-spline fitting (B-DMFA to estimate mass balanced fluxes. Smoother fits were achieved using reduced number of knots and parameters. Additionally, computation time was greatly reduced using a new heuristic algorithm for knot placement. B-DMFA revealed that Chinese hamster ovary cells shifted from 37 °C to 32 °C maintained a constant IgG volume-specific productivity, whereas the productivity for the controls peaked during mid-exponential growth phase and declined afterward. The observed 42% increase in product titer at 32 °C was explained by a prolonged cell growth with high cell viability, a larger cell volume and a more stable volume-specific productivity. Keywords: Dynamic, Metabolism, Flux analysis, CHO cells, Temperature shift, B-spline curve fitting

Second Law of Thermodynamics Applied to Metabolic Networks

Science.gov (United States)

Nigam, R.; Liang, S.

2003-01-01

We present a simple algorithm based on linear programming, that combines Kirchoff's flux and potential laws and applies them to metabolic networks to predict thermodynamically feasible reaction fluxes. These law's represent mass conservation and energy feasibility that are widely used in electrical circuit analysis. Formulating the Kirchoff's potential law around a reaction loop in terms of the null space of the stoichiometric matrix leads to a simple representation of the law of entropy that can be readily incorporated into the traditional flux balance analysis without resorting to non-linear optimization. Our technique is new as it can easily check the fluxes got by applying flux balance analysis for thermodynamic feasibility and modify them if they are infeasible so that they satisfy the law of entropy. We illustrate our method by applying it to the network dealing with the central metabolism of Escherichia coli. Due to its simplicity this algorithm will be useful in studying large scale complex metabolic networks in the cell of different organisms.

The Effects of Curcumin and Curcumin-Phospholipid Complex on the Serum Pro-oxidant-Antioxidant Balance in Subjects with Metabolic Syndrome.

Science.gov (United States)

Ghazimoradi, Maryam; Saberi-Karimian, Maryam; Mohammadi, Farzane; Sahebkar, Amirhossein; Tavallaie, Shima; Safarian, Hamideh; Ferns, Gordon A; Ghayour-Mobarhan, Majid; Moohebati, Mohsen; Esmaeili, Habibollah; Ahmadinejad, Malihe

2017-11-01

Metabolic syndrome (MetS) is defined by a clustering of metabolic and anthropometric abnormalities and is associated by an increased risk of cardiovascular disease. We have investigated the effect of curcumin supplementation on the serum pro-oxidant-antioxidant balance (PAB) in patients with MetS. This double-blind, randomized, placebo-controlled trial was conducted over 6 weeks. Subjects (n = 120) were randomly allocated to one of three groups (curcumin, phospholipidated curcumin, and placebo). The curcumin group received 1 g/day of simple curcumin, the phospholipidated curcumin group received 1 g/day of phospholipidated curcumin (containing 200 mg of pure curcumin), and the control group received 1 g/day of placebo. Serum PAB was measured before and after the intervention (at baseline and at 6 weeks). Data analyses were performed using spss software (version 16.0). Serum PAB increased significantly in the curcumin group (p curcumin group, elevation of PAB level was not significant (p = 0.053). The results of our study did not suggest any improvement of PAB following supplementation with curcumin in MetS subjects. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Circulating Metabolic Profile of High Producing Holstein Dairy Cows

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Aliasghar CHALMEH

2015-07-01

Full Text Available Assessing the metabolic profile based on the concept that the laboratory measurement of certain circulating components is a tool to evaluate metabolic status of dairy cows. Veterinarian also can evaluate the energy input-output relationships by assessing the metabolic profile to prevent and control of negative energy balance, metabolic disorders and nutritional insufficiencies. In the present study, 25 multiparous Holstein dairy cows were divided to 5 equal groups containing early, mid and late lactation, and far-off and close-up dry. Blood samples were collected from all cows through jugular venipuncture and sera were evaluated for glucose, insulin, β-hydroxybutyric acid (BHBA, non-esterified fatty acid (NEFA, cholesterol, triglyceride (TG, high, low and very low density lipoproteins (HDL, LDL and VLDL. Insulin levels in mid lactation and close-up dry cows were significantly higher than other groups (P<0.05 and the lowest insulin concentration was detected in far-off dry group. Serum concentrations of NEFA and BHBA in early and mid-lactation and close-up dry cows were significantly higher than late lactation and far-off dry animals (P<0.05. Baseline levels of cholesterol in mid and late lactation were significantly higher than other groups. The level of LDL in mid lactation cows was higher than others significantly, and its value in far-off dry cows was significantly lower than other group (P<0.05. It may be concluded that the detected changes among different groups induce commonly by negative energy balance, lactogenesis and fetal growth in each state. The presented metabolic profile can be considered as a tool to assess the energy balance in dairy cows at different physiologic states. It can be used to evaluate the metabolic situations of herd and manage the metabolic and production disorders.

Evaluation of water balance in a population of older adults. A case control study.

Science.gov (United States)

Malisova, Olga; Poulia, Kalliopi-Anna; Kolyzoi, Kleoniki; Lysandropoulos, Athanasios; Sfendouraki, Kalliopi; Kapsokefalou, Maria

2018-04-01

Older adults are at risk for dehydration and its' potentially life-threatening consequences. Unrecognized dehydration can complicate chronic medical problems and increase morbidity. The objective of the study was to estimate water balance, intake and loss in elderly people living in Greece using the Water Balance Questionnaire (WBQ). WBQ was administered in winter to 108 independents (65-81yrs) (Group A), 94 independents (82-92yrs) (Group B) and 51 hospitalized (65-92yrs) (Group C). A database from previous study of 335 adults (18-65yrs) (Control Group) used for comparison. Mean estimates of water balance, intake and loss were, respectively, for Group A -749 ± 1386 mL/day, 2571 ± 739 mL/day and 3320 ± 1216 mL/day, for Group B -38 ± 933 mL/day, 2571 ± 739 mL/day and 3320 ± 1216 mL/day, for Group C 64 ± 1399 mL/day, 2586 ± 1071 mL/day and 2522 ± 1048 mL/day and for Control Group -253 ± 1495 mL/day, 2912 ± 1025 mL/day and 3492 ± 2099 mL/day. Significant differences were detected in water balance, intake and loss (p < 0.01). Water balance and water intake in Group A was the lowest. For Groups A, B, C and Control, contribution of solid foods to water intake was 36%, 29%, 32%, 25%, of drinking water was 32%, 48%, 45%, 47%, of beverages was 32%, 23%, 23% and 28% respectively. Significant differences observed in the contribution of drinking water and beverages (p < 0.01). Group A had lower water balance and water intake. Groups B and C had lower water intake from beverages. Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

[A 5-year interval report on study of burn metabolism and nutrition].

Science.gov (United States)

Wang, S L

1992-12-01

This paper introduces the essential experiences concerning studies of burn metabolism and nutrition in our institute in the past five years. 1. Three new and practical animal models were developed for studying gastro-enteral nutrition in burns. 2. With indirect calorimetry, resting energy expenditure (REE) of 92 burn adult patients were measured and analyzed, and on the basis of which a new formula for calculating nutritional supplement in Chinese burn adults was proposed: kcal/day = 1,000 x M2 (body surface area) + 25 x % TBSA (total burn surface area). 3. Through experimental and clinical studies, it was found that antiouperoxide agents (such as SOD, CAT), tolbutamide, glutamine and Chinese herb decoction Sizunzituang all exhibited modulating effects on postburn metabolism and nutrition, e.g. decreasing catabolism, reducing negative nitrogen balance, stimulating secretion of insulin, enhancing tissue utilization of glucose, maintaining the mass of enteral mucosa and improving functions of viscerae. 4. A new less irritating, simple and easy-to-introduce nasal-enteral nutrition tube was devised, which could pass through the pylorus easily into the duodenum usually within 6hrs without using a stylet. It would be useful in the early postburn enteral nutrition supplementation.

Balancing cellular redox metabolism in microbial electrosynthesis and electro fermentation - A chance for metabolic engineering.

Science.gov (United States)

Kracke, Frauke; Lai, Bin; Yu, Shiqin; Krömer, Jens O

2018-01-01

More and more microbes are discovered that are capable of extracellular electron transfer, a process in which they use external electrodes as electron donors or acceptors for metabolic reactions. This feature can be used to overcome cellular redox limitations and thus optimizing microbial production. The technologies, termed microbial electrosynthesis and electro-fermentation, have the potential to open novel bio-electro production platforms from sustainable energy and carbon sources. However, the performance of reported systems is currently limited by low electron transport rates between microbes and electrodes and our limited ability for targeted engineering of these systems due to remaining knowledge gaps about the underlying fundamental processes. Metabolic engineering offers many opportunities to optimize these processes, for instance by genetic engineering of pathways for electron transfer on the one hand and target product synthesis on the other hand. With this review, we summarize the status quo of knowledge and engineering attempts around chemical production in bio-electrochemical systems from a microbe perspective. Challenges associated with the introduction or enhancement of extracellular electron transfer capabilities into production hosts versus the engineering of target compound synthesis pathways in natural exoelectrogens are discussed. Recent advances of the research community in both directions are examined critically. Further, systems biology approaches, for instance using metabolic modelling, are examined for their potential to provide insight into fundamental processes and to identify targets for metabolic engineering. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Human Body Exergy Metabolism

OpenAIRE

Mady, Carlos Eduardo Keutenedjian

2013-01-01

The exergy analysis of the human body is a tool that can provide indicators of health and life quality. To perform the exergy balance it is necessary to calculate the metabolism on an exergy basis, or metabolic exergy, although there is not yet consensus in its calculation procedure. Hence, the aim of this work is to provide a general method to evaluate this physical quantity for human body based on indirect calorimetry data. To calculate the metabolism on an exergy basis it is necessary to d...

Simulating Serial-Target Antibacterial Drug Synergies Using Flux Balance Analysis

DEFF Research Database (Denmark)

Krueger, Andrew S.; Munck, Christian; Dantas, Gautam

2016-01-01

Flux balance analysis (FBA) is an increasingly useful approach for modeling the behavior of metabolic systems. However, standard FBA modeling of genetic knockouts cannot predict drug combination synergies observed between serial metabolic targets, even though such synergies give rise to some of t...

Increased heart rate variability but normal resting metabolic rate in hypocretin/orexin-deficient human narcolepsy.

NARCIS (Netherlands)

Fronczek, R.; Overeem, S.; Reijntjes, R.; Lammers, G.J.; Dijk, J.G.M.; Pijl, H.

2008-01-01

STUDY OBJECTIVES: We investigated autonomic balance and resting metabolic rate to explore their possible involvement in obesity in hypocretin/orexin-deficient narcoleptic subjects. METHODS: Resting metabolic rate (using indirect calorimetry) and variability in heart rate and blood pressure were

Noise effect in metabolic networks

International Nuclear Information System (INIS)

Zheng-Yan, Li; Zheng-Wei, Xie; Tong, Chen; Qi, Ouyang

2009-01-01

Constraint-based models such as flux balance analysis (FBA) are a powerful tool to study biological metabolic networks. Under the hypothesis that cells operate at an optimal growth rate as the result of evolution and natural selection, this model successfully predicts most cellular behaviours in growth rate. However, the model ignores the fact that cells can change their cellular metabolic states during evolution, leaving optimal metabolic states unstable. Here, we consider all the cellular processes that change metabolic states into a single term 'noise', and assume that cells change metabolic states by randomly walking in feasible solution space. By simulating a state of a cell randomly walking in the constrained solution space of metabolic networks, we found that in a noisy environment cells in optimal states tend to travel away from these points. On considering the competition between the noise effect and the growth effect in cell evolution, we found that there exists a trade-off between these two effects. As a result, the population of the cells contains different cellular metabolic states, and the population growth rate is at suboptimal states. (cross-disciplinary physics and related areas of science and technology)

Adaptive control of dynamic balance in human gait on a split-belt treadmill.

Science.gov (United States)

Buurke, Tom J W; Lamoth, Claudine J C; Vervoort, Danique; van der Woude, Lucas H V; den Otter, Rob

2018-05-17

Human bipedal gait is inherently unstable and staying upright requires adaptive control of dynamic balance. Little is known about adaptive control of dynamic balance in reaction to long-term, continuous perturbations. We examined how dynamic balance control adapts to a continuous perturbation in gait, by letting people walk faster with one leg than the other on a treadmill with two belts (i.e. split-belt walking). In addition, we assessed whether changes in mediolateral dynamic balance control coincide with changes in energy use during split-belt adaptation. In nine minutes of split-belt gait, mediolateral margins of stability and mediolateral foot roll-off changed during adaptation to the imposed gait asymmetry, especially on the fast side, and returned to baseline during washout. Interestingly, no changes in mediolateral foot placement (i.e. step width) were found during split-belt adaptation. Furthermore, the initial margin of stability and subsequent mediolateral foot roll-off were strongly coupled to maintain mediolateral dynamic balance throughout the gait cycle. Consistent with previous results net metabolic power was reduced during split-belt adaptation, but changes in mediolateral dynamic balance control were not correlated with the reduction of net metabolic power during split-belt adaptation. Overall, this study has shown that a complementary mechanism of relative foot positioning and mediolateral foot roll-off adapts to continuously imposed gait asymmetry to maintain dynamic balance in human bipedal gait. © 2018. Published by The Company of Biologists Ltd.

Metabolic learning and memory formation by the brain influence systemic metabolic homeostasis

Science.gov (United States)

Zhang, Yumin; Liu, Gang; Yan, Jingqi; Zhang, Yalin; Li, Bo; Cai, Dongsheng

2015-01-01

Metabolic homeostasis is regulated by the brain, whether this regulation involves learning and memory of metabolic information remains unexplored. Here we use a calorie-based, taste-independent learning/memory paradigm to show that Drosophila form metabolic memories that help balancing food choice with caloric intake; however, this metabolic learning or memory is lost under chronic high-calorie feeding. We show that loss of individual learning/memory-regulating genes causes a metabolic learning defect, leading to elevated trehalose and lipids levels. Importantly, this function of metabolic learning requires not only the mushroom body but the hypothalamus-like pars intercerebralis, while NF-κB activation in the pars intercerebralis mimics chronic overnutrition in that it causes metabolic learning impairment and disorders. Finally, we evaluate this concept of metabolic learning/memory in mice, suggesting the hypothalamus is involved in a form of nutritional learning and memory, which is critical for determining resistance or susceptibility to obesity. In conclusion, our data indicate the brain, and potentially the hypothalamus, direct metabolic learning and the formation of memories, which contribute to the control of systemic metabolic homeostasis. PMID:25848677

Zea mays iRS1563: A Comprehensive Genome-Scale Metabolic Reconstruction of Maize Metabolism

Science.gov (United States)

Saha, Rajib; Suthers, Patrick F.; Maranas, Costas D.

2011-01-01

The scope and breadth of genome-scale metabolic reconstructions have continued to expand over the last decade. Herein, we introduce a genome-scale model for a plant with direct applications to food and bioenergy production (i.e., maize). Maize annotation is still underway, which introduces significant challenges in the association of metabolic functions to genes. The developed model is designed to meet rigorous standards on gene-protein-reaction (GPR) associations, elementally and charged balanced reactions and a biomass reaction abstracting the relative contribution of all biomass constituents. The metabolic network contains 1,563 genes and 1,825 metabolites involved in 1,985 reactions from primary and secondary maize metabolism. For approximately 42% of the reactions direct literature evidence for the participation of the reaction in maize was found. As many as 445 reactions and 369 metabolites are unique to the maize model compared to the AraGEM model for A. thaliana. 674 metabolites and 893 reactions are present in Zea mays iRS1563 that are not accounted for in maize C4GEM. All reactions are elementally and charged balanced and localized into six different compartments (i.e., cytoplasm, mitochondrion, plastid, peroxisome, vacuole and extracellular). GPR associations are also established based on the functional annotation information and homology prediction accounting for monofunctional, multifunctional and multimeric proteins, isozymes and protein complexes. We describe results from performing flux balance analysis under different physiological conditions, (i.e., photosynthesis, photorespiration and respiration) of a C4 plant and also explore model predictions against experimental observations for two naturally occurring mutants (i.e., bm1 and bm3). The developed model corresponds to the largest and more complete to-date effort at cataloguing metabolism for a plant species. PMID:21755001

Beta-cell function is associated with metabolic syndrome in Mexican subjects

Directory of Open Access Journals (Sweden)

Pérez-Fuentes

2010-08-01

Full Text Available Blanca G Baez-Duarte1,3, María Del Carmen Sánchez-Guillén3†, Ricardo Pérez-Fuentes2,3, Irma Zamora-Ginez1,3, Bertha Alicia Leon-Chavez1, Cristina Revilla-Monsalve4, Sergio Islas-Andrade41Posgrado en Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, México; 2Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, México; 3Centro de Investigación Biomédica de Oriente, Instituto Mexicano del Seguro Social, Atlixco, Puebla, México; 4Multidiciplinary Research Group on Diabetes (José Sánchez-Corona, Fernando Guerrero-Romero, Martha Rodriguez-Moran, Agustin Madero, Jorge Escobedo-de-la-Peña, Silvia Flores-Martinez, Esperanza, Martinez-Abundis, Manuel Gonzalez-Ortiz, Alberto Rascon-Pacheco, Margarita Torres-Tamayo, Instituto Mexicano del Seguro Social, México, Distrito Federal, México; †María Del Carmen Sánchez-Guillén passed away on 27 November 2009.Aims: The clinical diagnosis of metabolic syndrome does not find any parameters to evaluate the insulin sensitivity (IS or β-cell function. The evaluation of these parameters would detect early risk of developing metabolic syndrome. The aim of this study is to determine the relationship between β-cell function and presence of metabolic syndrome in Mexican subjects.Material and methods: This study is part of the Mexican Survey on the Prevention of Diabetes (MexDiab Study with headquarters in the city of Puebla, Mexico. The study comprised of 444 subjects of both genders, aged between 18 and 60 years and allocated into two study groups: (1 control group of individuals at metabolic balance without metabolic syndrome and (2 group composed of subjects with metabolic syndrome and diagnosed according to the criteria of the Third Report of the National Cholesterol Education Program Expert Panel on Defection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Anthropometric, biochemical, and clinical assessments were carried out.Results: Average age of the

Influence of age and magnesium on calcium metabolism in rats

International Nuclear Information System (INIS)

McElroy, S.T.; Link, J.E.; Dowdy, R.P.; Zinn, K.R.; Ellersieck, M.R.

1991-01-01

This study evaluates the effect of dietary magnesium concentration on calcium metabolism in rats of differing ages. Young (3 wk) and old (18 mo) Fischer 344 rats were fed the AIN-76A diet modified to contain either low (218 mg/kg) or adequate (419 mg/kg) Mg for 4 wk. Some rats subsequently underwent a metabolic balance study (12 d duration). Other rats were gavaged with approximately 220 KBq (6 microCi) of 47 Ca; daily fecal and urine collections were made and periodic whole body radioactivity determined. Femurs were removed and analyzed. Calcium retention and balance were not affected by Mg in young rats. In old rats low Mg intake increased apparent Ca balance. Young rats retained about 3.25 times more of the original dose of 47 Ca than did old rats. Young rats retained more 47 Ca in the femur than did old rats; Mg intake had little effect. Aging accelerated Ca turnover rate, and whole body retention data suggest that adequate Mg does not significantly reduce Ca turnover

Metabolic signals in sleep regulation: recent insights

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Shukla C

2016-01-01

Full Text Available Charu Shukla, Radhika Basheer Department of Psychiatry, VA Boston Healthcare System, Harvard Medical School, West Roxbury, MA, USA Abstract: Sleep and energy balance are essential for health. The two processes act in concert to regulate central and peripheral homeostasis. During sleep, energy is conserved due to suspended activity, movement, and sensory responses, and is redirected to restore and replenish proteins and their assemblies into cellular structures. During wakefulness, various energy-demanding activities lead to hunger. Thus, hunger promotes arousal, and subsequent feeding, followed by satiety that promotes sleep via changes in neuroendocrine or neuropeptide signals. These signals overlap with circuits of sleep-wakefulness, feeding, and energy expenditure. Here, we will briefly review the literature that describes the interplay between the circadian system, sleep-wake, and feeding-fasting cycles that are needed to maintain energy balance and a healthy metabolic profile. In doing so, we describe the neuroendocrine, hormonal/peptide signals that integrate sleep and feeding behavior with energy metabolism. Keywords: sleep, energy balance, hypothalamus, metabolism, homeostasis

13C Metabolic Flux Analysis for systematic metabolic engineering of S. cerevisiae for overproduction of fatty acids.

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Amit Ghosh

2016-10-01

Full Text Available Efficient redirection of microbial metabolism into the abundant production of desired bioproducts remains non-trivial. Here we used flux-based modeling approaches to improve yields of fatty acids in S. cerevisiae. We combined 13C labeling data with comprehensive genome-scale models to shed light onto microbial metabolism and improve metabolic engineering efforts. We concentrated on studying the balance of acetyl-CoA, a precursor metabolite for the biosynthesis of fatty acids. A genome-wide acetyl-CoA balance study showed ATP citrate lyase from Y. lipolytica as a robust source of cytoplasmic acetyl-CoA and malate synthase as a desirable target for down-regulation in terms of acetyl-CoA consumption. These genetic modifications were applied to S. cerevisiae WRY2, a strain that is capable of producing 460 mg L of free fatty acids. With the addition of ATP citrate lyase and down-regulation of malate synthase the engineered strain produced 26 per cent more free fatty acids. Further increases in free fatty acid production of 33 per cent were obtained by knocking out the cytoplasmic glycerol-3-phosphate dehydrogenase, which flux analysis had shown was competing for carbon flux upstream with the carbon flux through the acetyl-CoA production pathway in the cytoplasm. In total, the genetic interventions applied in this work increased fatty acid production by 70 per cent.

Home-based balance training programme using Wii Fit with balance board for Parkinsons's disease: a pilot study.

Science.gov (United States)

Esculier, Jean-Francois; Vaudrin, Joanie; Bériault, Patrick; Gagnon, Karine; Tremblay, Louis E

2012-02-01

To evaluate the effects of a home-based balance training programme using visual feedback (Nintendo Wii Fit game with balance board) on balance and functional abilities in subjects with Parkinson's disease, and to compare the effects with a group of paired healthy subjects. Ten subjects with moderate Parkinson's disease and 8 healthy elderly subjects. Subjects participated in a 6-week home-based balance training programme using Nintendo Wii Fit and balance board. Baseline measures were taken before training for the Sit-to-Stand test (STST), Timed-Up-and-Go (TUG), Tinetti Performance Oriented Mobility Assessment (POMA), 10-m walk test, Community Balance and Mobility assessment (CBM), Activities-specific Balance and Confidence scale (ABC), unipodal stance duration, and a force platform. All measurements were taken again after 3 and 6 weeks of training. The Parkinson's disease group significantly improved their results in TUG, STST, unipodal stance, 10-m walk test, CBM, POMA and force platform at the end of the 6-week training programme. The healthy subjects group significantly improved in TUG, STST, unipodal stance and CBM. This pilot study suggests that a home-based balance programme using Wii Fit with balance board could improve static and dynamic balance, mobility and functional abilities of people affected by Parkinson's disease.

Kisspeptin and energy balance in reproduction.

Science.gov (United States)

De Bond, Julie-Ann P; Smith, Jeremy T

2014-03-01

Kisspeptin is vital for the neuroendocrine regulation of GNRH secretion. Kisspeptin neurons are now recognized as a central pathway responsible for conveying key homeostatic information to GNRH neurons. This pathway is likely to mediate the well-established link between energy balance and reproductive function. Thus, in states of severely altered energy balance (either negative or positive), fertility is compromised, as is Kiss1 expression in the arcuate nucleus. A number of metabolic modulators have been proposed as regulators of kisspeptin neurons including leptin, ghrelin, pro-opiomelanocortin (POMC), and neuropeptide Y (NPY). Whether these regulate kisspeptin neurons directly or indirectly will be discussed. Moreover, whether the stimulatory role of leptin on reproduction is mediated by kisspeptin directly will be questioned. Furthermore, in addition to being expressed in GNRH neurons, the kisspeptin receptor (Kiss1r) is also expressed in other areas of the brain, as well as in the periphery, suggesting alternative roles for kisspeptin signaling outside of reproduction. Interestingly, kisspeptin neurons are anatomically linked to, and can directly excite, anorexigenic POMC neurons and indirectly inhibit orexigenic NPY neurons. Thus, kisspeptin may have a direct role in regulating energy balance. Although data from Kiss1r knockout and WT mice found no differences in body weight, recent data indicate that kisspeptin may still play a role in food intake and glucose homeostasis. Thus, in addition to regulating reproduction, and mediating the effect of energy balance on reproductive function, kisspeptin signaling may also be a direct regulator of metabolism.

A delicate balance? : a study of work-life conflicts, work-life enrichment, and worklife balance among management consultants in Norway

OpenAIRE

Nabong, Tristán; Trønnes, Hannah

2016-01-01

The purpose of this study is to identify the relationship among work-life balance, work-life enrichment, and work-life conflict by looking into the status, condition, and experiences of management consultants in Norway. The need to develop methods to achieve an optimal balance between employees’ productivity, work habits and personal life has sparked numerous studies investigating work-life balance in recent years. Because very few previous studies have dealt with work-life balance in the man...

Reconstruction of the central carbon metabolism of Aspergillus niger

DEFF Research Database (Denmark)

David, Helga; Åkesson, Mats Fredrik; Nielsen, Jens

2003-01-01

The topology of central carbon metabolism of Aspergillus niger was identified and the metabolic network reconstructed, by integrating genomic, biochemical and physiological information available for this microorganism and other related fungi. The reconstructed network may serve as a valuable...... of metabolic fluxes using metabolite balancing. This framework was employed to perform an in silico characterisation of the phenotypic behaviour of A. niger grown on different carbon sources. The effects on growth of single reaction deletions were assessed and essential biochemical reactions were identified...... for different carbon sources. Furthermore, application of the stoichiometric model for assessing the metabolic capabilities of A. niger to produce metabolites was evaluated by using succinate production as a case study....

[Brief disserting on the balance of internal environment in burn disease].

Science.gov (United States)

Han, C M; Wang, X G

2017-08-20

The essential internal environment in human being involves water, electrolyte, and acid-base balance, which is the basis of balance and stability of internal environment in other systems. For burn patients, the balance of internal environment, referring to metabolism, nutrition, inflammatory response, and immunoreaction, is one of the most important aspects in burn disease. This paper aims to briefly elaborate the balance of internal environment after burn, with the purpose to promote the basic and clinical research in this field.

Association Study between Ghrelin Gene Polymorphism and Metabolic Syndrome in a Han Chinese Population.

Science.gov (United States)

You, Yueyue; Yu, Yaqin; Wu, Yanhua; Rao, Wenwang; Zhang, Yangyu; Liu, Yingyu; Yang, Guang; Fu, Yingli; Shi, Jieping; Kou, Changgui

2017-01-01

Ghrelin, in humans, is a hormone secreted from the stomach with an orexigenic effect, which is good for digestion and absorption, as well as regulating physical growth, metabolism, and energy balance. It is also involved in the development of metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM). This study assessed the association between single nucleotide variants of the GHRL gene and the risk of metabolic syndrome in a Han Chinese population. A case-control study was performed on 3780 Han Chinese comprising 1813 MetS cases and 1967 controls. Three missense polymorphisms in GHRL (rs26802, rs10490816, and rs696217) were selected, and the association between these polymorphisms and the risk of MetS was investigated. Metabolic syndrome was defined according to the criteria of the International Diabetes Federation (IDF). Using Pearson's 2 test, we found that there were no significant differences in genotype distributions and allele frequencies between cases and controls (all p > 0.05). There were also no significant differences in haplotype distributions between MetS cases and healthy controls. Furthermore, we confirmed that rs26802 of the GHRL gene is associated with body mass index (BMI), waist circumference, systolic blood pressure (SBP), and fasting glucose; rs10490816 is associated with triglycerides (TG) and total cholesterol (TC); while rs696217 is associated with hip circumference and fasting glucose. We concluded that mutations in the GHRL gene did not confer risk for MetS in our study population. Therefore, functional analysis and replication studies in other populations are needed to further investigate the exact role of the GHRL gene in MetS.

Metabolic learning and memory formation by the brain influence systemic metabolic homeostasis.

Science.gov (United States)

Zhang, Yumin; Liu, Gang; Yan, Jingqi; Zhang, Yalin; Li, Bo; Cai, Dongsheng

2015-04-07

Metabolic homeostasis is regulated by the brain, but whether this regulation involves learning and memory of metabolic information remains unexplored. Here we use a calorie-based, taste-independent learning/memory paradigm to show that Drosophila form metabolic memories that help in balancing food choice with caloric intake; however, this metabolic learning or memory is lost under chronic high-calorie feeding. We show that loss of individual learning/memory-regulating genes causes a metabolic learning defect, leading to elevated trehalose and lipid levels. Importantly, this function of metabolic learning requires not only the mushroom body but also the hypothalamus-like pars intercerebralis, while NF-κB activation in the pars intercerebralis mimics chronic overnutrition in that it causes metabolic learning impairment and disorders. Finally, we evaluate this concept of metabolic learning/memory in mice, suggesting that the hypothalamus is involved in a form of nutritional learning and memory, which is critical for determining resistance or susceptibility to obesity. In conclusion, our data indicate that the brain, and potentially the hypothalamus, direct metabolic learning and the formation of memories, which contribute to the control of systemic metabolic homeostasis.

Metabolic syndrome in hyperprolactinemia

DEFF Research Database (Denmark)

Andersen, Marianne; Glintborg, Dorte

2018-01-01

The metabolic syndrome (MetS) is a conglomerate of clinical findings that convey into increased morbidity and mortality from type 2 diabetes mellitus (T2D) and cardiovascular disease. Hyperprolactinemia (hyperPRL) is associated with components of MetS, especially during pregnancy. Endogenous levels...... in patients with T2D. HyperPRL is a biomarker for decreased dopaminergic tonus in the hypothalamic-pituitary circuit. Patients with a prolactinoma, patients with schizophrenia and/or T2D often have disturbances in this balance and the finding of lower prolactin (PRL) levels in polycystic ovary syndrome (PCOS......) may indicate increased dopaminergic tonus. Recent studies supported that PRL levels within or above reference range may be differently related to MetS. In healthy study populations and in PCOS, PRL levels were inversely associated with metabolic risk markers. Ongoing research on PRL fragments...

Construction of a Genome-Scale Metabolic Model of Arthrospira platensis NIES-39 and Metabolic Design for Cyanobacterial Bioproduction.

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Katsunori Yoshikawa

Full Text Available Arthrospira (Spirulina platensis is a promising feedstock and host strain for bioproduction because of its high accumulation of glycogen and superior characteristics for industrial production. Metabolic simulation using a genome-scale metabolic model and flux balance analysis is a powerful method that can be used to design metabolic engineering strategies for the improvement of target molecule production. In this study, we constructed a genome-scale metabolic model of A. platensis NIES-39 including 746 metabolic reactions and 673 metabolites, and developed novel strategies to improve the production of valuable metabolites, such as glycogen and ethanol. The simulation results obtained using the metabolic model showed high consistency with experimental results for growth rates under several trophic conditions and growth capabilities on various organic substrates. The metabolic model was further applied to design a metabolic network to improve the autotrophic production of glycogen and ethanol. Decreased flux of reactions related to the TCA cycle and phosphoenolpyruvate reaction were found to improve glycogen production. Furthermore, in silico knockout simulation indicated that deletion of genes related to the respiratory chain, such as NAD(PH dehydrogenase and cytochrome-c oxidase, could enhance ethanol production by using ammonium as a nitrogen source.

Enhancing flora balance in the gastrointestinal tract of mice by lactic acid bacteria from Chinese sourdough and enzyme activities indicative of metabolism of protein, fat, and carbohydrate by the flora.

Science.gov (United States)

Yang, Dong; Yu, Xiaomin; Wu, Yaoping; Chen, Xingxing; Wei, Hua; Shah, Nagendra P; Xu, Feng

2016-10-01

In this study, we investigated the effect of administration of 5 strains of lactic acid bacteria (LAB) isolated from traditional Chinese sourdough on the flora balance of gastrointestinal tract of mice. We specifically measured Enterococcus, Enterobacter, Bacteroides, and Lactobacillus by plate count and real-time PCR methods, and α-glucosidase, lactate dehydrogenase, esterase, and aminopeptidase activities as indicative of metabolism of sugar, fat, and protein from LAB isolated from feces of mice in vitro. The results showed that administration of Lactobacillus acidophilus LAC0201 and Lactobacillus fermentum LFE0302 lowered the uricacid index of serum. Lactobacillus acidophilus LAC0201, L. fermentum LFE0302, as well as Lactobacillus curvatus LCU0401 administration resulted in a reduction in the opportunistic pathogens (i.e., Enterococcus and Enterobacter), meanwhile, administration of L. fermentum LFE0302 and Lactobacillus sp. ULA0104 resulted in an increase in the counts of Lactobacillus. Lactobacillus fermentum LFE0302 administration increased starch digestion of intestinal flora after 4wk of feeding and also resulted in increased α-glucosidase activity in the intestinal flora after 3wk of feeding. We found a similar trend in esterase activity after administration of L. acidophilus LAC0201 for 3wk. Hence, our study suggested that LAB from Chinese sourdough might be used as potential probiotics to strengthen the flora balance in gastrointestinal tract and positively change the metabolism of nutrients through bacterial enzyme activities. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Influence of physical fitness on cardio-metabolic risk factors in European children. The IDEFICS study.

Science.gov (United States)

Zaqout, M; Michels, N; Bammann, K; Ahrens, W; Sprengeler, O; Molnar, D; Hadjigeorgiou, C; Eiben, G; Konstabel, K; Russo, P; Jiménez-Pavón, D; Moreno, L A; De Henauw, S

2016-07-01

The aim of the study was to assess the associations of individual and combined physical fitness components with single and clustering of cardio-metabolic risk factors in children. This 2-year longitudinal study included a total of 1635 European children aged 6-11 years. The test battery included cardio-respiratory fitness (20-m shuttle run test), upper-limb strength (handgrip test), lower-limb strength (standing long jump test), balance (flamingo test), flexibility (back-saver sit-and-reach) and speed (40-m sprint test). Metabolic risk was assessed through z-score standardization using four components: waist circumference, blood pressure (systolic and diastolic), blood lipids (triglycerides and high-density lipoprotein) and insulin resistance (homeostasis model assessment). Mixed model regression analyses were adjusted for sex, age, parental education, sugar and fat intake, and body mass index. Physical fitness was inversely associated with clustered metabolic risk (P<0.001). All coefficients showed a higher clustered metabolic risk with lower physical fitness, except for upper-limb strength (β=0.057; P=0.002) where the opposite association was found. Cardio-respiratory fitness (β=-0.124; P<0.001) and lower-limb strength (β=-0.076; P=0.002) were the most important longitudinal determinants. The effects of cardio-respiratory fitness were even independent of the amount of vigorous-to-moderate activity (β=-0.059; P=0.029). Among all the metabolic risk components, blood pressure seemed not well predicted by physical fitness, while waist circumference, blood lipids and insulin resistance all seemed significantly predicted by physical fitness. Poor physical fitness in children is associated with the development of cardio-metabolic risk factors. Based on our results, this risk might be modified by improving mainly cardio-respiratory fitness and lower-limb muscular strength.

Stem cell metabolism in tissue development and aging

Science.gov (United States)

Shyh-Chang, Ng; Daley, George Q.; Cantley, Lewis C.

2013-01-01

Recent advances in metabolomics and computational analysis have deepened our appreciation for the role of specific metabolic pathways in dictating cell fate. Once thought to be a mere consequence of the state of a cell, metabolism is now known to play a pivotal role in dictating whether a cell proliferates, differentiates or remains quiescent. Here, we review recent studies of metabolism in stem cells that have revealed a shift in the balance between glycolysis, mitochondrial oxidative phosphorylation and oxidative stress during the maturation of adult stem cells, and during the reprogramming of somatic cells to pluripotency. These insights promise to inform strategies for the directed differentiation of stem cells and to offer the potential for novel metabolic or pharmacological therapies to enhance regeneration and the treatment of degenerative disease. PMID:23715547

The impact of music on metabolism.

Science.gov (United States)

Yamasaki, Alisa; Booker, Abigail; Kapur, Varun; Tilt, Alexandra; Niess, Hanno; Lillemoe, Keith D; Warshaw, Andrew L; Conrad, Claudius

2012-01-01

The study of music and medicine is a rapidly growing field that in the past, has been largely focused on the use of music as a complementary therapy. Increasing interest has been centered on understanding the physiologic mechanisms underlying the effects of music and, more recently, the suggested role of music in modulating metabolic responses. Research has established a role for music in the regulation of the hypothalamic-pituitary axis, the sympathetic nervous system, and the immune system, which have key functions in the regulation of metabolism and energy balance. More recent findings have shown a role for music in the metabolic recovery from stress, the regulation of gastric and intestinal motility, the moderation of cancer-related gastrointestinal symptoms, and the increase of lipid metabolism and lactic acid clearance during exercise and postexercise recovery. The purpose of this article is to summarize the most current understanding of the mechanisms by which music affects the metabolic responses in the context of potential applications. Copyright © 2012 Elsevier Inc. All rights reserved.

TORCing up metabolic control in the brain.

Science.gov (United States)

Hietakangas, Ville; Cohen, Stephen M

2008-05-01

Transducer of regulated CREB activity 2 (TORC2) is a coactivator of CREB and an important regulator of energy balance in mammals through control of gluconeogenesis in the liver. In this issue of Cell Metabolism, Wang and coworkers (2008) report an intriguing role for Drosophila TORC in the neuronal regulation of metabolism.

Mechanisms of redox metabolism and cancer cell survival during extracellular matrix detachment.

Science.gov (United States)

Hawk, Mark A; Schafer, Zachary T

2018-01-16

Non-transformed cells that become detached from the extracellular matrix (ECM) undergo dysregulation of redox homeostasis and cell death. In contrast, cancer cells often acquire the ability to mitigate programmed cell death pathways and recalibrate the redox balance to survive after ECM detachment, facilitating metastatic dissemination. Accordingly, recent studies of the mechanisms by which cancer cells overcome ECM detachment-induced metabolic alterations have focused on mechanisms in redox homeostasis. The insights into these mechanisms may inform the development of therapeutics that manipulate redox homeostasis to eliminate ECM-detached cancer cells. Here, we review how ECM-detached cancer cells balance redox metabolism for survival. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Thermal balance of Nellore cattle

Science.gov (United States)

de Melo Costa, Cíntia Carol; Maia, Alex Sandro Campos; Nascimento, Sheila Tavares; Nascimento, Carolina Cardoso Nagib; Neto, Marcos Chiquitelli; de França Carvalho Fonsêca, Vinícius

2018-05-01

This work aimed at characterizing the thermal balance of Nellore cattle from the system of indirect calorimetry using a facial mask. The study was conducted at the Animal Biometeorology Laboratory of the São Paulo State University, Jaboticabal, Brazil. Five male Nellore weighing 750 ± 62 kg, at similar ages and body conditions were distributed in four 5 × 5 Latin squares (5 days of records and five schedules) during 20 days. Physiological and environmental measurements were obtained from the indirect calorimetry system using a facial mask. Respiratory parameters, hair coat, skin, and rectal temperature were continuously recorded. From this, metabolic heat production, sensible and latent ways of heat transfer were calculated. Metabolic heat production had an average value of 146.7 ± 0.49 W m-2 and did not change ( P > 0.05) over the range of air temperature (24 to 35 °C). Sensible heat flow reached 60.08 ± 0.81 W m-2 when air temperature ranged from 24 to 25 °C, being negligible in conditions of temperature above 33 °C. Most of the heat produced by metabolism was dissipated by cutaneous evaporation when air temperature was greater than 30 °C. Respiratory parameters like respiratory rate and ventilation remained stable ( P > 0.05) in the range of temperature studied. Under shade conditions and air temperature range from 24 to 35 °C, metabolic heat production, respiratory rate, and ventilation of mature Nellore cattle remain stable, which is indicative of low energetic cost to the thermoregulation.

Reduced blood nrf-2 mRNA in local overweight boys at risk of metabolic complications: a study in San Luis City, San Luis, Argentina.

Science.gov (United States)

Santillán, Lucas D; Moyano, Marta; Frau, Martín; Flores, Orlando; Siewert, Susana; Zirulnick, Fanny; Ramirez, Dario C; Giménez, Maria S

2013-10-01

Childhood overweight (OW) is a matter of public health concern because of its long-term impact on adulthood health. NF-E2-related factor 2 (Nrf-2) regulates the antioxidant/lipogenic response to a sustained positive energy balance that prevails during weight gain. Here we aimed at studying a possible link between OW and Nrf-2-dependent antioxidant/lipogenic response in a local population of boys at risk of metabolic complications. We measured clinical and biochemical parameters related to lipid metabolism, oxidative stress, and metabolic syndrome in a population of OW boys [body mass index (BMI) percentile ≥85(th) and Luis City, San Luis, Argentina. Compared to NW, OW boys had lower insulin sensitivity, an altered plasma lipid profile, and increased markers of oxidative stress and inflammatory fatty acids. OW boys also had a higher atherogenic index and peripheral insulin resistance than NW boys. We also found that glutathione peroxidase activity and the reduced glutathione to oxidized glutathione ratio were lower in OW boys than NW boys, suggesting that OW boys may have an altered antioxidant response to oxidative stress. Finally, Nrf-2 expression negatively correlated with metabolic syndrome parameters in OW boys. Our data suggest that OW boys have a reduced antioxidant and lipogenic response to a positive energy balance, resulting in oxidative stress, insulin resistance, and risk of developing metabolic complications. Our data also provide a rationale for nutritional interventions aimed at restoring Nrf-2 expression to reduce the risk of metabolic complications in OW boys.

Modelling central metabolic fluxes by constraint-based optimization reveals metabolic reprogramming of developing Solanum lycopersicum (tomato) fruit.

Science.gov (United States)

Colombié, Sophie; Nazaret, Christine; Bénard, Camille; Biais, Benoît; Mengin, Virginie; Solé, Marion; Fouillen, Laëtitia; Dieuaide-Noubhani, Martine; Mazat, Jean-Pierre; Beauvoit, Bertrand; Gibon, Yves

2015-01-01

Modelling of metabolic networks is a powerful tool to analyse the behaviour of developing plant organs, including fruits. Guided by our current understanding of heterotrophic metabolism of plant cells, a medium-scale stoichiometric model, including the balance of co-factors and energy, was constructed in order to describe metabolic shifts that occur through the nine sequential stages of Solanum lycopersicum (tomato) fruit development. The measured concentrations of the main biomass components and the accumulated metabolites in the pericarp, determined at each stage, were fitted in order to calculate, by derivation, the corresponding external fluxes. They were used as constraints to solve the model by minimizing the internal fluxes. The distribution of the calculated fluxes of central metabolism were then analysed and compared with known metabolic behaviours. For instance, the partition of the main metabolic pathways (glycolysis, pentose phosphate pathway, etc.) was relevant throughout fruit development. We also predicted a valid import of carbon and nitrogen by the fruit, as well as a consistent CO2 release. Interestingly, the energetic balance indicates that excess ATP is dissipated just before the onset of ripening, supporting the concept of the climacteric crisis. Finally, the apparent contradiction between calculated fluxes with low values compared with measured enzyme capacities suggest a complex reprogramming of the metabolic machinery during fruit development. With a powerful set of experimental data and an accurate definition of the metabolic system, this work provides important insight into the metabolic and physiological requirements of the developing tomato fruits. © 2014 The Authors The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

Fat and carbohydrate metabolism during submaximal exercise in children.

Science.gov (United States)

Aucouturier, Julien; Baker, Julien S; Duché, Pascale

2008-01-01

During exercise, the contribution of fat and carbohydrate to energy expenditure is largely modulated by the intensity of exercise. Age, a short- or long-term diet enriched in carbohydrate or fat substrate stores, training and gender are other factors that have also been found to affect this balance. These factors have been extensively studied in adults from the perspective of improving performance in athletes, or from a health perspective in people with diseases. During the last decade, lifestyle changes associated with high-energy diets rich in lipid and reduced physical activity have contributed to the increase in childhood obesity. This lifestyle change has emerged as a serious health problem favouring the early development of cardiovascular diseases, insulin resistance or type 2 diabetes mellitus. Increasing physical activity levels in young people is important to increase energy expenditure and promote muscle oxidative capacity. Therefore, it is surprising that the regulation of balance between carbohydrate and lipid use during exercise has received much less attention in children than in adults. In this review, we have focused on the factors that affect carbohydrate and lipid metabolism during exercise and have identified areas that may be relevant in explaining the higher contribution of lipid to energy expenditure in children when compared with adults. Low muscle glycogen content is possibly associated with a low activity of glycolytic enzymes and high oxidative capacity, while lower levels of sympathoadrenal hormones are likely to favour lipid metabolism in children. Changes in energetic metabolism occurring during adolescence are also dependent on pubertal events with an increase in testosterone in boys and estrogen and progesterone in girls. The profound effects of ovarian hormones on carbohydrate and fat metabolism along with their effects on oxidative enzymes could explain that differences in substrate metabolism have not always been observed between

The Energy Balance Study: The Design and Baseline Results for a Longitudinal Study of Energy Balance

Science.gov (United States)

Hand, Gregory A.; Shook, Robin P.; Paluch, Amanda E.; Baruth, Meghan; Crowley, E. Patrick; Jaggers, Jason R.; Prasad, Vivek K.; Hurley, Thomas G.; Hebert, James R.; O'Connor, Daniel P.; Archer, Edward; Burgess, Stephanie; Blair, Steven N.

2013-01-01

Purpose: The Energy Balance Study (EBS) was a comprehensive study designed to determine over a period of 12 months the associations of caloric intake and energy expenditure on changes in body weight and composition in a population of healthy men and women. Method: EBS recruited men and women aged 21 to 35 years with a body mass index between 20…

Application of dynamic flux balance analysis to an industrial Escherichia coli fermentation.

Science.gov (United States)

Meadows, Adam L; Karnik, Rahi; Lam, Harry; Forestell, Sean; Snedecor, Brad

2010-03-01

We have developed a reactor-scale model of Escherichia coli metabolism and growth in a 1000 L process for the production of a recombinant therapeutic protein. The model consists of two distinct parts: (1) a dynamic, process specific portion that describes the time evolution of 37 process variables of relevance and (2) a flux balance based, 123-reaction metabolic model of E. coli metabolism. This model combines several previously reported modeling approaches including a growth rate-dependent biomass composition, maximum growth rate objective function, and dynamic flux balancing. In addition, we introduce concentration-dependent boundary conditions of transport fluxes, dynamic maintenance demands, and a state-dependent cellular objective. This formulation was able to describe specific runs with high-fidelity over process conditions including rich media, simultaneous acetate and glucose consumption, glucose minimal media, and phosphate depleted media. Furthermore, the model accurately describes the effect of process perturbations--such as glucose overbatching and insufficient aeration--on growth, metabolism, and titer. (c) 2009 Elsevier Inc. All rights reserved.

How body balance influences political party evaluations: A wii balance board study

NARCIS (Netherlands)

K. Dijkstra (Katinka); A. Eerland (Anita); J.M. Zijlmans (Mark); L.S. Post (Lysanne)

2012-01-01

textabstractEmbodied cognition research has shown how actions or body positions may affect cognitive processes, such as autobiographical memory retrieval or judgments. The present study examined the role of body balance (to the left or the right) in participants on their attributions to political

Adipose tissue NAD+-homeostasis, sirtuins and poly(ADP-ribose) polymerases -important players in mitochondrial metabolism and metabolic health.

Science.gov (United States)

Jokinen, Riikka; Pirnes-Karhu, Sini; Pietiläinen, Kirsi H; Pirinen, Eija

2017-08-01

Obesity, a chronic state of energy overload, is characterized by adipose tissue dysfunction that is considered to be the major driver for obesity associated metabolic complications. The reasons for adipose tissue dysfunction are incompletely understood, but one potential contributing factor is adipose tissue mitochondrial dysfunction. Derangements of adipose tissue mitochondrial biogenesis and pathways associate with obesity and metabolic diseases. Mitochondria are central organelles in energy metabolism through their role in energy derivation through catabolic oxidative reactions. The mitochondrial processes are dependent on the proper NAD + /NADH redox balance and NAD + is essential for reactions catalyzed by the key regulators of mitochondrial metabolism, sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs). Notably, obesity is associated with disturbed adipose tissue NAD + homeostasis and the balance of SIRT and PARP activities. In this review we aim to summarize existing literature on the maintenance of intracellular NAD + pools and the function of SIRTs and PARPs in adipose tissue during normal and obese conditions, with the purpose of comprehending their potential role in mitochondrial derangements and obesity associated metabolic complications. Understanding the molecular mechanisms that are the root cause of the adipose tissue mitochondrial derangements is crucial for developing new effective strategies to reverse obesity associated metabolic complications. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Dietary Strategies Implicated in the Prevention and Treatment of Metabolic Syndrome

OpenAIRE

de la Iglesia, Rocio; Loria-Kohen, Viviana; Zulet, Maria Angeles; Martinez, Jose Alfredo; Reglero, Guillermo; Ramirez de Molina, Ana

2016-01-01

Metabolic syndrome (MetS) is established as the combination of central obesity and different metabolic disturbances, such as insulin resistance, hypertension and dyslipidemia. This cluster of factors affects approximately 10%–50% of adults worldwide and the prevalence has been increasing in epidemic proportions over the last years. Thus, dietary strategies to treat this heterogenic disease are under continuous study. In this sense, diets based on negative-energy-balance, the Mediterranean die...

Shift work and its association with metabolic disorders.

Science.gov (United States)

Brum, Maria Carlota Borba; Filho, Fábio Fernandes Dantas; Schnorr, Claudia Carolina; Bottega, Gustavo Borchardt; Rodrigues, Ticiana C

2015-01-01

Although the health burden of shift work has not been extensively studied, evidence suggests that it may affect the metabolic balance and cause obesity and other metabolic disorders. Sleep deprivation, circadian desynchronization and behavioral changes in diet and physical activity are among the most commonly mentioned factors in studies of the association between night work and metabolic disorders. Individual adaptation to night work depends greatly on personal factors such as family and social life, but occupational interventions may also make a positive contribution to the transition to shift work, such as exposure to bright lights during the night shift, melatonin use, shift regularity and clockwise rotation, and dietary adaptations for the metabolic needs of night workers. The evaluation of the impact of night work on health and of the mechanisms underlying this relationship can serve as a basis for intervention strategies to minimize the health burden of shift work. This review aimed to identify highlights regarding therapeutic implications following the association between night and shift work and metabolic disorders, as well as the mechanisms and pathways responsible for these relationships.

Advantages and disadvantages of the animal models v. in vitro studies in iron metabolism: a review.

Science.gov (United States)

García, Y; Díaz-Castro, J

2013-10-01

Iron deficiency is the most common nutritional deficiency in the world. Special molecules have evolved for iron acquisition, transport and storage in soluble, nontoxic forms. Studies about the effects of iron on health are focused on iron metabolism or nutrition to prevent or treat iron deficiency and anemia. These studies are focused in two main aspects: (1) basic studies to elucidate iron metabolism and (2) nutritional studies to evaluate the efficacy of iron supplementation to prevent or treat iron deficiency and anemia. This paper reviews the advantages and disadvantages of the experimental models commonly used as well as the methods that are more used in studies related to iron. In vitro studies have used different parts of the gut. In vivo studies are done in humans and animals such as mice, rats, pigs and monkeys. Iron metabolism is a complex process that includes interactions at the systemic level. In vitro studies, despite physiological differences to humans, are useful to increase knowledge related to this essential micronutrient. Isotopic techniques are the most recommended in studies related to iron, but their high cost and required logistic, making them difficult to use. The depletion-repletion of hemoglobin is a method commonly used in animal studies. Three depletion-repletion techniques are mostly used: hemoglobin regeneration efficiency, relative biological values (RBV) and metabolic balance, which are official methods of the association of official analytical chemists. These techniques are well-validated to be used as studies related to iron and their results can be extrapolated to humans. Knowledge about the main advantages and disadvantages of the in vitro and animal models, and methods used in these studies, could increase confidence of researchers in the experimental results with less costs.

Myths and methodologies: Making sense of exercise mass and water balance.

Science.gov (United States)

Cheuvront, Samuel N; Montain, Scott J

2017-09-01

What is the topic of this review? There is a need to revisit the basic principles of exercise mass and water balance, the use of common equations and the practice of interpreting outcomes. What advances does it highlight? We propose use of the following equation as a way of simplifying exercise mass and water balance calculations in conditions where food is not consumed and waste is not excreted: ∆body mass - 0.20 g/kcal -1  = ∆body water. The relative efficacy of exercise drinking behaviours can be judged using the following equation: percentage dehydration = [(∆body mass - 0.20 g kcal -1 )/starting body mass] × 100. Changes in body mass occur because of flux in liquids, solids and gases. This knowledge is crucial for understanding metabolism, health and human water needs. In exercise science, corrections to observed changes in body mass to estimate water balance are inconsistently applied and often misinterpreted, particularly after prolonged exercise. Although acute body mass losses in response to exercise can represent a close surrogate for body water losses, the discordance between mass and water balance equivalence becomes increasingly inaccurate as more and more energy is expended. The purpose of this paper is briefly to clarify the roles that respiratory water loss, gas exchange and metabolic water production play in the correction of body mass changes for fluid balance determinations during prolonged exercise. Computations do not include waters of association with glycogen because any movement of water among body water compartments contributes nothing to water or mass flux from the body. Estimates of sweat loss from changes in body mass should adjust for non-sweat losses when possible. We propose use of the following equation as a way of simplifying the study of exercise mass and water balance: ∆body mass - 0.20 g kcal -1  = ∆body water. This equation directly controls for the influence of energy expenditure on body mass

Metabolic regulation and behavior: how hunger produces arousal - an insect study.

Science.gov (United States)

Wicher, Dieter

2007-12-01

The metabolic state affects the level of general activity of an organism. Satiety is related to relaxation while hunger is coupled to elevated activity which supports the chance to balance the energy deficiency. The unrestricted food availability in modern industrial nations along with no required locomotor activity are risk factors to develop disorders such as obesity. One of the strategies to find new targets for future treatment of metabolic disorders in men is to gain detailed knowledge of molecular and cellular mechanisms involved in the regulation of metabolic homeostasis in less complex, i.e. invertebrate systems. This review reports recent molecular studies in insects about how hunger signals may be linked to global activation. Adipokinetic peptide hormones (AKHs) are the insect counterpart to the mammalian glucagon. They are released upon lack of energy and mobilize internal fuel reserves. In addition, AKHs stimulate the locomotor activity which involves their activity within the central nervous system. In the cockroach Periplaneta americana various neurons express the AKH receptor. Some of these, the dorsal unpaired median (DUM) neurons belonging to a general arousal system, release the biogenic amine octopamine, the insect counterpart to mammalian adrenergic hormones. The two Periplaneta AKHs activate Gs proteins, and AKH I also potently activates Gq proteins. AKH I and - less effectively - AKH II accelerate spiking of DUM neurons via an increase of a pacemaking Ca2+ current. Systemically injected AKH I stimulates locomotion in contrast to AKH II. This behavioral difference corresponds to the different effectiveness of the AKHs on the level of G-proteins.

Metabolic evaluation of dairy cows submitted to three different strategies to decrease the effects of negative energy balance in early postpartum

Directory of Open Access Journals (Sweden)

Alejandra M.B García

2011-12-01

Full Text Available In early lactation dairy cattle suffer metabolic alterations caused by negative energy balance, which predisposes to fatty liver and ketosis. The aim of this study was to evaluate the metabolic condition of high yielding dairy cows subjected to three treatments for preventing severe lipomobilization and ketosis in early lactation. Fifty four multiparous Holstein cows yielding >30 L/day were divided into four groups: control (CN= no treatment, glucose precursor (PG= propylene-glycol, hepatic protector (Mp= Mercepton®, and energy supplement with salts of linolenic and linoleic faty acids (Mg-E= Megalac-E®. Treatments were administrated randomly at moment of calving until 8 weeks postpartum. Blood samples were collected on days 1, 7, 14, 21, 28, 35, 42 and 49 postpartum. Body condition score (BCS was evaluated at the same periods and milk yield was recorded at 2nd, 4th, 5th, 6th, 7th, and 8th weeks of lactation. Concentrations of non-esterified fatty acids (NEFA, albumin, AST, ß-hydroxybutyrate (BHBA, cholesterol, glucose, total protein, urea and triglycerides were analyzed in blood samples. Cut-off points for subclinical ketosis were defined when BHBA >1.4 mmol/L and NEFA >0.7 mmol/L. General occurrence of subclinical ketosis was 24% during the period. An ascendant curve of cholesterol and glucose was observed from the 1st to the 8th week of lactation, while any tendency was observed with BHBA and NEFA, although differences among treatments were detected (p<0.05. BCS decreased from a mean of 3.85 at 1st week to 2.53 at 8th week of lactation (p=0.001. Milk yield was higher in the Mg-E group compared with the other treatment groups (p<0.05 Compared with the CN group, the treatments with Mp and PG did not show significant differences in blood biochemistry and milk yield. Cows receiving PG and Mg-E showed higher values of BHBA and NEFA (P<0.05, indicating accentuated lipomobilization. Supplementation with Mg-E also resulted in significant higher

Nitrogen balance in patients with hemiparetic stroke during the subacute rehabilitation phase.

Science.gov (United States)

Wada, A; Kawakami, M; Otsuka, T; Aoki, H; Anzai, A; Yamada, Y; Liu, F; Otaka, E; Akaboshi, K; Liu, M

2017-06-01

In highly invasive diseases, metabolism commonly changes. Hypercatabolism is frequent in acute stroke, and nitrogen balance tends to be negative. However, there has been no study describing nitrogen balance in subacute and chronic stroke patients. The present study aimed to examine nitrogen balance in the subacute and chronic phases and to identify the factors related to it. Nitrogen balance was calculated from the collected urine of 56 patients with subacute stroke [mean (SD) 53.8 (18.4) days post-stroke] who were admitted for rehabilitation for their first-ever ischaemic or nonsurgical haemorrhagic stroke. In the first experiment, their nitrogen balance was measured during the rehabilitation phase, and factors (type, severity of hemiparesis, activities of daily living, dysphagia and malnutrition status) related to it were evaluated. The second experiment was performed to describe the time course of nitrogen balance in 31 consecutive patients, with assessments made at admission and at discharge. Nitrogen balance was positive in all patients in the subacute phase. A significant difference was seen in nitrogen balance between high and low fat-free mass in male patients. In the chronic phase, nitrogen balance was positive in 96% of the patients. There was no significant difference in nitrogen balance between discharge and admission. In the subacute and chronic phases of stroke, it was confirmed that hypercatabolism had resolved and that intensive rehabilitation is possible in the convalescent period of stroke. © 2017 The British Dietetic Association Ltd.

Investigation of bone and mineral metabolism in hyperthyroidism before and after treatment using calcitonin, 47Ca and balance studies

International Nuclear Information System (INIS)

Hendriks, J.Th.A.M.; Smeenk, D.

1979-01-01

Seventeen normocalcaemic patients with severe hyperthyroidism were examined before therapy was initiated; 9 were re-examined about 1 year later. Studies with 47 Ca under balance conditions and with calcitonin demonstrated a high rate of bone resorption in untreated patients. As a result of the increased bone turnover, the reaction to 6 MRC units of porcine calcitonin iv was more marked in the untreated than in the treated patients, or the control group. In contrast to the normal diurnal pattern for PO 4 , it was found that during fasting the plasma PO 4 level increases in the morning in patients with hyperthyroidism. This increase which was not suppressed by the administered dose of calcitonin developed in spite of an elevated urinary PO 4 excretion. After treatment, the serum Ca concentration as well as the urinary and faecal Ca excretion was decreased. The Ca balance improved; the rapidly-exchangeable Ca pool returned to normal. The slowly-exchangeable and the total Ca pools, however, remained enlarged. The rate of bone resorption normalized. The accretion rate on the other hand remained elevated. This is attributed to continued enhancement of bone formation to compensate for the previous loss of bony tissue. (author)

Influence of creatine supplementation on indicators of glucose metabolism in skeletal muscle of exercised rats

Directory of Open Access Journals (Sweden)

Michel Barbosa de Araújo

2013-12-01

Full Text Available The purpose of this study was to evaluate the effect of creatine supplementation in the diet on indicators of glucose metabolism in skeletal muscle of exercised rats. Forty Wistar adult rats were distributed into four groups for eight weeks: 1 Control: sedentary rats that received balanced diet; 2 Creatine control: sedentary rats that received supplementation of 2% creatine in the balanced diet; 3 Trained: rats that ran on a treadmill at the Maximal Lactate Steady State and received balanced diet; and 4 Supplemented-trained: rats that ran on a treadmill at the Maximal Lactate Steady State and received creatine supplementation (2% in the balanced diet. The hydric intake increased and the body weight gain decreased in the supplemented-trained group. In the soleus muscle, the glucose oxidation increased in both supplemented groups. The production of lactate and glycemia during glucose tolerance test decreased in the supplemented-trained group. Creatine supplementation in conjunction with exercise training improved muscular glycidic metabolism of rats.

[Disorders of the acid-base balance and the anion gap].

Science.gov (United States)

Kimmel, Martin; Alscher, Mark Dominik

2016-10-01

The regulation of the acid-base balance and pH is critical for the organism. The most important buffer system is CO 2 / HCO 3 - . The kidney controls systemic bicarbonate and therefore the metabolic regulation and the lung is relevant for respiratory regulation by an effective CO 2 elimination. There are four acid-base disorders with two metabolic and two respiratory disorders (acidosis and alkalosis). The anion gap enables a further workup of metabolic acidosis. © Georg Thieme Verlag KG Stuttgart · New York.

Genome-scale reconstruction of the metabolic network in Yersinia pestis CO92

Science.gov (United States)

Navid, Ali; Almaas, Eivind

2007-03-01

The gram-negative bacterium Yersinia pestis is the causative agent of bubonic plague. Using publicly available genomic, biochemical and physiological data, we have developed a constraint-based flux balance model of metabolism in the CO92 strain (biovar Orientalis) of this organism. The metabolic reactions were appropriately compartmentalized, and the model accounts for the exchange of metabolites, as well as the import of nutrients and export of waste products. We have characterized the metabolic capabilities and phenotypes of this organism, after comparing the model predictions with available experimental observations to evaluate accuracy and completeness. We have also begun preliminary studies into how cellular metabolism affects virulence.

Metabolic changes in cancer: beyond the Warburg effect

Institute of Scientific and Technical Information of China (English)

Weihua Wu; Shimin Zhao

2013-01-01

Altered metabolism is one of the hallmarks of cancer cells.The best-known metabolic abnormality in cancer cells is the Warburg effect,which demonstrates an increased glycolysis even in the presence of oxygen.However,tumor-related metabolic abnormalities are not limited to altered balance between glucose fermentation and oxidative phosphorylation.Key tumor genes such as p53 and c-myc are found to be master regulators of metabolism.Metabolic enzymes such as succinate dehydrogenase,fumarate hydratase,pyruvate kinase,and isocitrate dehydrogenase mutations or expressing level alterations are all linked to tumorigenesis.In this review,we introduce some of the cancer-associated metabolic disorders and current understanding of their molecular tumorigenic mechanisms.

Interchangeability of the Wii Balance Board for Bipedal Balance Assessment.

Science.gov (United States)

Bonnechère, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

2015-08-27

Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. The objective of this crossover study is to assess the interchangeability of the Wii Balance Board. A total of 6 subjects participated in the study and their balance was assessed using 4 different Wii Balance Boards. Trials were recorded simultaneously with Wii Balance Boards and with a laboratory force plate. Nine relevant clinical parameters were derived from center of pressure displacement data obtained from Wii Balance Board and force plate systems. Intraclass correlation coefficients (ICC), F tests, and Friedman tests were computed to assess the agreement between trials and to compare the Wii Balance Board and force plate results. Excellent correlations were found between the Wii Balance Board and force plate (mean ρ =.83). With the exception of 2 parameters, strong to excellent agreements were found for the 7 remaining parameters (ICC=.96). No significant differences were found between trials recorded with different Wii Balance Boards. Our results indicate that for most of the parameters analyzed, balance and posture assessed with one Wii Balance Board were statistically similar to results obtained from another. Furthermore, the good correlation between the Wii Balance Board and force plate results shows that Wii Balance Boards can be reliably used for scientific assessment using most of the parameters analyzed in this study. These results also suggest that the Wii Balance Board could be used in multicenter studies and therefore, would allow for the creation of larger populations for clinical studies. Ethical Committee of the Erasme Hospital (CCB B406201215142

The neuropeptide allatostatin A regulates metabolism and feeding decisions in Drosophila

DEFF Research Database (Denmark)

Hentze, Julie Lilith; Carlsson, Mikael A.; Kondo, Shu

2015-01-01

Coordinating metabolism and feeding is important to avoid obesity and metabolic diseases, yet the underlying mechanisms, balancing nutrient intake and metabolic expenditure, are poorly understood. Several mechanisms controlling these processes are conserved in Drosophila, where homeostasis and en...

Validation of measures from the smartphone sway balance application: a pilot study.

Science.gov (United States)

Patterson, Jeremy A; Amick, Ryan Z; Thummar, Tarunkumar; Rogers, Michael E

2014-04-01

A number of different balance assessment techniques are currently available and widely used. These include both subjective and objective assessments. The ability to provide quantitative measures of balance and posture is the benefit of objective tools, however these instruments are not generally utilized outside of research laboratory settings due to cost, complexity of operation, size, duration of assessment, and general practicality. The purpose of this pilot study was to assess the value and validity of using software developed to access the iPod and iPhone accelerometers output and translate that to the measurement of human balance. Thirty healthy college-aged individuals (13 male, 17 female; age = 26.1 ± 8.5 years) volunteered. Participants performed a static Athlete's Single Leg Test protocol for 10 sec, on a Biodex Balance System SD while concurrently utilizing a mobile device with balance software. Anterior/posterior stability was recorded using both devices, described as the displacement in degrees from level, and was termed the "balance score." There were no significant differences between the two reported balance scores (p = 0.818. Mean balance score on the balance platform was 1.41 ± 0.90, as compared to 1.38 ± 0.72 using the mobile device. There is a need for a valid, convenient, and cost-effective tool to objectively measure balance. Results of this study are promising, as balance score derived from the Smartphone accelerometers were consistent with balance scores obtained from a previously validated balance system. However, further investigation is necessary as this version of the mobile software only assessed balance in the anterior/posterior direction. Additionally, further testing is necessary on a healthy populations and as well as those with impairment of the motor control system. Level 2b (Observational study of validity)(1.)

Effects of dry-rolled or high-moisture corn with twenty-five or forty-five percent wet distillers' grains with solubles on energy metabolism, nutrient digestibility, and macromineral balance in finishing beef steers

Science.gov (United States)

The effects of feeding dry-rolled corn (DRC) or high-moisture corn (HMC) with 25% and 45% wet distillers grains with solubles (WDGS) on energy metabolism, and nutrient and mineral balance were evaluated in 8 finishing beef steers using a replicated Latin square design. The model included the fixed ...

Home-based balance training using the Wii balance board: a randomized, crossover pilot study in multiple sclerosis.

Science.gov (United States)

Prosperini, Luca; Fortuna, Deborah; Giannì, Costanza; Leonardi, Laura; Marchetti, Maria Rita; Pozzilli, Carlo

2013-01-01

To evaluate the effectiveness of a home-based rehabilitation of balance using the Nintendo Wii Balance Board System (WBBS) in patients affected by multiple sclerosis (MS). In this 24-week, randomized, 2-period crossover pilot study, 36 patients having an objective balance disorder were randomly assigned in a 1:1 ratio to 2 counterbalanced arms. Group A started a 12-week period of home-based WBBS training followed by a 12-week period without any intervention; group B received the treatment in reverse order. As endpoints, we considered the mean difference (compared with baseline) in force platform measures (i.e., the displacement of body center of pressure in 30 seconds), 4-step square test (FSST), 25-foot timed walking test (25-FWT), and 29-item MS Impact Scale (MSIS-29), as evaluated after 12 weeks and at the end of the 24-week study period. The 2 groups did not differ in baseline characteristics. Repeated-measures analyses of variance showed significant time × treatment effects, indicating that WBBS was effective in ameliorating force platform measures (F = 4.608, P = .016), FSST (F = 3.745, P = .034), 25-FWT (F = 3.339, P = .048), and MSIS-29 (F = 4.282, P = .023). Five adverse events attributable to the WBSS training (knee or low back pain) were recorded, but only 1 patient had to retire from the study. A home-based WBBS training might potentially provide an effective, engaging, balance rehabilitation solution for people with MS. However, the risk of WBBS training-related injuries should be carefully balanced with benefits. Further studies, including cost-effectiveness analyses, are warranted to establish whether WBBS may be useful in the home setting.

[METABOLIC STATUS OF PATIENTS OF DIFFERENT AGE GROUPS ON THE STAGES OF OSTEOARTHRITIS].

Science.gov (United States)

Stogov, M V; Ovchinnikov, E N; Sazonova, N V

2015-01-01

This study investigated the biochemical parameters of blood and urine in patients with osteoarthritis in the stages of the pathological process in different age groups. The patients of all age groups in the stages of osteoarthritis demonstrated metabolic acidosis, activation of the antioxidant system and increase in acute phase proteins. In addition to the total for all age groups metabolic shifts the characteristic age-related changes were observed: activated reaction of lipid peroxidation in middle-aged patients and negative calcium balance, with increasing energy metabolism disorders in elderly patients.

A STUDY ON EMPLOYEE WORK LIFE BALANCE IN PRECISION INFOMATIC PVT LTD

OpenAIRE

B. Arul Jenifer; S. Vengatesh

2018-01-01

The main goal of this paper is to understand the relationship between work life balance & Employee Engagement. Further this paper highlights contextual factors affecting Employee Engagement and Work Life Balance. This paper is built on relevant literature and recent studies on Work Life Balance Also, the results of the study show inverse relationship between pleasure & work. There has been an increased focus on balancing multiple life roles and managing the boundary between work and family. T...

Diet-Induced Low-Grade Metabolic Acidosis and Clinical Outcomes: A Review

Directory of Open Access Journals (Sweden)

Renata Alves Carnauba

2017-05-01

Full Text Available Low-grade metabolic acidosis is a condition characterized by a slight decrease in blood pH, within the range considered normal, and feeding is one of the main factors that may influence the occurrence of such a condition. The excessive consumption of acid precursor foods (sources of phosphorus and proteins, to the detriment of those precursors of bases (sources of potassium, calcium, and magnesium, leads to acid-base balance volubility. If this condition occurs in a prolonged, chronic way, low-grade metabolic acidosis can become significant and predispose to metabolic imbalances such as kidney stone formation, increased bone resorption, reduced bone mineral density, and the loss of muscle mass, as well as the increased risk of chronic diseases such as type 2 diabetes mellitus, hypertension, and non-alcoholic hepatic steatosis. Considering the increase in the number of studies investigating the influence of diet-induced metabolic acidosis on clinical outcomes, this review gathers the available evidence evaluating the association of this disturbance and metabolic imbalances, as well as related mechanisms. It is necessary to look at the western dietary pattern of most countries and the increasing incidence of non-comunicable diseases for the balance between fruit and vegetable intake and the appropriate supply of protein, mainly from animal sources, so that it does not exceed the daily recommendations.

Inflammation and metabolic disorders.

Science.gov (United States)

Navab, Mohamad; Gharavi, Nima; Watson, Andrew D

2008-07-01

Poor nutrition, overweight and obesity have increasingly become a public health concern as they affect many metabolic disorders, including heart disease, diabetes, digestive system disorders, and renal failure. Study of the effects of life style including healthy nutrition will help further elucidate the mechanisms involved in the adverse effects of poor nutrition. Unhealthy life style including poor nutrition can result in imbalance in our oxidation/redox systems. Lipids can undergo oxidative modification by lipoxygenases, cyclooxygenases, myeloperoxidase, and other enzymes. Oxidized phospholipids can induce inflammatory molecules in the liver and other organs. This can contribute to inflammation, leading to coronary heart disease, stroke, renal failure, inflammatory bowl disease, metabolic syndrome, bone and joint disorders, and even certain types of cancer. Our antioxidant and antiinflammatory defense mechanisms contribute to a balance between the stimulators and the inhibitors of inflammation. Beyond a point, however, these systems might be overwhelmed and eventually fail. High-density lipoprotein is a potent inhibitor of the formation of toxic oxidized lipids. High-density lipoprotein is also an effective system for stimulating the genes whose products are active in the removal, inactivation, and elimination of toxic lipids. Supporting the high-density lipoprotein function should help maintain the balance in these systems. It is hoped that the present report would elucidate some of the ongoing work toward this goal.

Interchangeability of the Wii Balance Board for Bipedal Balance Assessment

OpenAIRE

Bonnech?re, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

2015-01-01

Background Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. Objective The objective of this crossover study is to assess the interchangeabilit...

lumpGEM: Systematic generation of subnetworks and elementally balanced lumped reactions for the biosynthesis of target metabolites.

Directory of Open Access Journals (Sweden)

Meric Ataman

2017-07-01

Full Text Available In the post-genomic era, Genome-scale metabolic networks (GEMs have emerged as invaluable tools to understand metabolic capabilities of organisms. Different parts of these metabolic networks are defined as subsystems/pathways, which are sets of functional roles to implement a specific biological process or structural complex, such as glycolysis and TCA cycle. Subsystem/pathway definition is also employed to delineate the biosynthetic routes that produce biomass building blocks. In databases, such as MetaCyc and SEED, these representations are composed of linear routes from precursors to target biomass building blocks. However, this approach cannot capture the nested, complex nature of GEMs. Here we implemented an algorithm, lumpGEM, which generates biosynthetic subnetworks composed of reactions that can synthesize a target metabolite from a set of defined core precursor metabolites. lumpGEM captures balanced subnetworks, which account for the fate of all metabolites along the synthesis routes, thus encapsulating reactions from various subsystems/pathways to balance these metabolites in the metabolic network. Moreover, lumpGEM collapses these subnetworks into elementally balanced lumped reactions that specify the cost of all precursor metabolites and cofactors. It also generates alternative subnetworks and lumped reactions for the same metabolite, accounting for the flexibility of organisms. lumpGEM is applicable to any GEM and any target metabolite defined in the network. Lumped reactions generated by lumpGEM can be also used to generate properly balanced reduced core metabolic models.

Influence of injected caffeine on the metabolism of calcium and the retention and excretion of sodium, potassium, phosphorus, magnesium, zinc and copper in rats.

Science.gov (United States)

Yeh, J K; Aloia, J F; Semla, H M; Chen, S Y

1986-02-01

Mineral metabolism was studied by the metabolic balance technique in rats with and without administration of caffeine. Caffeine was injected subcutaneously each day at either 2.5 mg or 10 mg/100 g body weight for 2 wk before the balance studies. Urinary volume excretion was higher in the group given caffeine than in the control group, but the creatinine clearance was not different. Urinary excretion of potassium, sodium, inorganic phosphate, magnesium and calcium, but not of zinc and copper, was also higher in the rats given caffeine. The rank order of the difference was the same as the percent of ingested mineral excreted in urine in the absence of caffeine. Caffeine caused a negative balance of potassium, sodium and inorganic phosphate. There was no significant difference from the control levels and in the apparent metabolic balance of calcium and magnesium. The urinary and fecal excretion of zinc and copper were found to be unaffected by caffeine. It is suggested that chronic administration of caffeine may lead to a tendency toward deficiency of those minerals that are excreted primarily in urine.

Cerebral (31)P magnetic resonance spectroscopy and systemic acid-base balance during hypoxia in fetal sheep.

NARCIS (Netherlands)

Cappellen van Walsum, A.M. van; Rijpkema, M.J.P.; Heerschap, A.; Oeseburg, B.; Nijhuis, J.G.; Jongsma, H.W.

2003-01-01

The purpose of this study was to investigate cerebral energy metabolism and acid-base homeostasis during impaired oxygen supply in fetal sheep. Systemic acid-base balance was correlated with the sequence in changes of cerebral phosphorus metabolite ratios and intracellular pH. Phosphorus magnetic

Sample size calculation in metabolic phenotyping studies.

Science.gov (United States)

Billoir, Elise; Navratil, Vincent; Blaise, Benjamin J

2015-09-01

The number of samples needed to identify significant effects is a key question in biomedical studies, with consequences on experimental designs, costs and potential discoveries. In metabolic phenotyping studies, sample size determination remains a complex step. This is due particularly to the multiple hypothesis-testing framework and the top-down hypothesis-free approach, with no a priori known metabolic target. Until now, there was no standard procedure available to address this purpose. In this review, we discuss sample size estimation procedures for metabolic phenotyping studies. We release an automated implementation of the Data-driven Sample size Determination (DSD) algorithm for MATLAB and GNU Octave. Original research concerning DSD was published elsewhere. DSD allows the determination of an optimized sample size in metabolic phenotyping studies. The procedure uses analytical data only from a small pilot cohort to generate an expanded data set. The statistical recoupling of variables procedure is used to identify metabolic variables, and their intensity distributions are estimated by Kernel smoothing or log-normal density fitting. Statistically significant metabolic variations are evaluated using the Benjamini-Yekutieli correction and processed for data sets of various sizes. Optimal sample size determination is achieved in a context of biomarker discovery (at least one statistically significant variation) or metabolic exploration (a maximum of statistically significant variations). DSD toolbox is encoded in MATLAB R2008A (Mathworks, Natick, MA) for Kernel and log-normal estimates, and in GNU Octave for log-normal estimates (Kernel density estimates are not robust enough in GNU octave). It is available at http://www.prabi.fr/redmine/projects/dsd/repository, with a tutorial at http://www.prabi.fr/redmine/projects/dsd/wiki. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Flux Balance Analysis of Cyanobacterial Metabolism.The Metabolic Network of Synechocystis sp. PCC 6803

Czech Academy of Sciences Publication Activity Database

Knoop, H.; Gründel, M.; Zilliges, Y.; Lehmann, R.; Hoffmann, S.; Lockau, W.; Steuer, Ralf

2013-01-01

Roč. 9, č. 6 (2013), e1003081-e1003081 ISSN 1553-7358 R&D Projects: GA MŠk(CZ) EE2.3.20.0256 Institutional support: RVO:67179843 Keywords : SP STRAIN PCC-6803 * SP ATCC 51142 * photoautotrophic metabolism * anacystis-nidulans * reconstructions * pathway * plants * models * growth Subject RIV: EI - Biotechnology ; Bionics Impact factor: 4.829, year: 2013

Establishing Normative Values for the Barnett Balance Assessment Tool: A Preliminary Study

Directory of Open Access Journals (Sweden)

Monica L. Cercone MSOTS

2014-04-01

Full Text Available The purpose of this study was to establish normative data for the Barnett Balance Assessment (BBA for individuals ages 18-70+ years. The BBA is a newly developed assessment tool that may address limitations present in other assessments currently used to detect balance deficits. The BBA was administered to 141 participants who had no history of medical issues that could impact balance. A review of the normative data collected indicated little variation in total assessment scores in the age categories of 18-29, 30-39, and 40-49, due to the presence of a ceiling effect. Variations existed in scores among participants in the remaining age categories (50-59, 60-69, and 70+. These findings may imply that the BBA has its greatest discriminative power in assessing individuals with impaired balance, and/or that the BBA is not sensitive enough to detect differences in individuals with mild balance impairments. The researchers suggest future studies be conducted with the BBA to establish norms with populations with known orthopedic or neurological conditions that may impair balance. Results of these studies could then be compared with the baseline data gathered in this study to determine the BBA’s usefulness in detecting balance impairments with clinical populations.

A Metabolic Study of Huntington's Disease.

Directory of Open Access Journals (Sweden)

Rajasree Nambron

Full Text Available Huntington's disease patients have a number of peripheral manifestations suggestive of metabolic and endocrine abnormalities. We, therefore, investigated a number of metabolic factors in a 24-hour study of Huntington's disease gene carriers (premanifest and moderate stage II/III and controls.Control (n = 15, premanifest (n = 14 and stage II/III (n = 13 participants were studied with blood sampling over a 24-hour period. A battery of clinical tests including neurological rating and function scales were performed. Visceral and subcutaneous adipose distribution was measured using magnetic resonance imaging. We quantified fasting baseline concentrations of glucose, insulin, cholesterol, triglycerides, lipoprotein (a, fatty acids, amino acids, lactate and osteokines. Leptin and ghrelin were quantified in fasting samples and after a standardised meal. We assessed glucose, insulin, growth hormone and cortisol concentrations during a prolonged oral glucose tolerance test.We found no highly significant differences in carbohydrate, protein or lipid metabolism markers between healthy controls, premanifest and stage II/III Huntington's disease subjects. For some markers (osteoprotegerin, tyrosine, lysine, phenylalanine and arginine there is a suggestion (p values between 0.02 and 0.05 that levels are higher in patients with premanifest HD, but not moderate HD. However, given the large number of statistical tests performed interpretation of these findings must be cautious.Contrary to previous studies that showed altered levels of metabolic markers in patients with Huntington's disease, our study did not demonstrate convincing evidence of abnormalities in any of the markers examined. Our analyses were restricted to Huntington's disease patients not taking neuroleptics, anti-depressants or other medication affecting metabolic pathways. Even with the modest sample sizes studied, the lack of highly significant results, despite many being tested, suggests that

Effects of dietary energy source on energy balance, metabolites and reproduction variables in dairy cows in early lactation

NARCIS (Netherlands)

Knegsel, van A.T.M.; Brand, van den H.; Dijkstra, J.; Kemp, B.

2007-01-01

This paper summarizes three recent studies by the same authors with the objective to study the effect of dietary energy source on the energy balance (EB) and risk for metabolic and reproductive disorders in dairy cows in early lactation. The first study, a literature survey, illustrated that feeding

Metabolic and cardiovascular effects of ghrelin

Directory of Open Access Journals (Sweden)

2012-03-01

Full Text Available Ghrelin is an endogenous ligand for growth hormone receptor, which is synthesized as a prohormone, and then proteolytically converted into 28-amino acid peptide. This peptide stimulates the secretion of growth hormone, regulates food intake, effect on carbohydrate and lipid metabolism. Ghrelin enhances the bioavailability of nitric oxide and maintains the balance between endothelin-1 and nitric oxide in the vascular wall. It increases cardiac output, and reduces blood pressure and systemic vascular resistance. Antiinflammatory effect of ghrelin is also appreciated. Since ghrelin is a circulating peptide that stimulates appetite and regulate energy balance, and its role in the development of obesity and type 2 diabetes it is the subject of intense research. A variety of metabolic functions of ghrelin requires extreme caution in the use of therapeutic approaches aimed at the stimulation or blockade of its action.

Emerging health problems among women: Inactivity, obesity, and metabolic syndrome

Directory of Open Access Journals (Sweden)

Yi-Ju Tsai

2014-02-01

Full Text Available The increase in obesity and metabolic syndrome has been documented worldwide. However, few studies have investigated the risk of inactivity, obesity, and metabolic syndrome specifically in women. Hormone balance plays a crucial role in regulating metabolism and helps to maintain optimal health. It is likely that the sex difference in obesity may be due to the variation in hormone concentration throughout a woman's life, which predisposes them to weight gain. This paper reviews previous literature and discusses factors that influence the risk of adiposity-related health consequences among women for three critical biological transitions throughout a woman's life: puberty, menopause, and pregnancy. To improve quality of life and metabolic health for women, interventions are needed to target women at different transition stages and provide tailored health education programs. Interventions should raise awareness of physical inactivity, obesity, and metabolic syndrome, and promote healthy behavioral change in women.

Occupational balance of women with rheumatoid arthritis: a qualitative study.

Science.gov (United States)

Stamm, Tanja; Wright, Jon; Machold, Klaus; Sadlo, Gaynor; Smolen, Josef

2004-01-01

Occupational balance has been shown to be an important factor in maintaining health. Rheumatoid arthritis (RA) reduces functional ability and quality of life and may thus reduce occupational balance. The aim of this qualitative pilot study was to explore occupational balance in women who have RA. Nine women with RA with past, but not current, paid work experience, no other confounding neuro-motor disease and with disease duration of 0.75-31 years were selected from an Austrian rheumatology outpatient clinic. Age range of the participants was 28-68 years. A semi-structured interview was conducted with each participant and transcribed verbatim. Data were analysed by the constant comparative method from an occupational perspective. Three main categories emerged: (1) The participants experienced a process of change that affected their occupational balance. (2) This new state of occupational balance was characterized by changed levels of involvement in physical, mental, social and rest occupations and by a certain level of unpredictability of symptoms. (3) Overall, the new state of occupational balance was valued differently: positively, indifferently or negatively. RA was found to have a considerable impact on occupational balance. The experience is not invariably seen as negative as previous literature would suggest. Further research should explore the longitudinal dimension of occupational balance in people with RA. Copyright (c) 2004 Whurr Publishers Ltd.

Elucidating dynamic metabolic physiology through network integration of quantitative time-course metabolomics

DEFF Research Database (Denmark)

Bordbar, Aarash; Yurkovich, James T.; Paglia, Giuseppe

2017-01-01

The increasing availability of metabolomics data necessitates novel methods for deeper data analysis and interpretation. We present a flux balance analysis method that allows for the computation of dynamic intracellular metabolic changes at the cellular scale through integration of time-course ab......The increasing availability of metabolomics data necessitates novel methods for deeper data analysis and interpretation. We present a flux balance analysis method that allows for the computation of dynamic intracellular metabolic changes at the cellular scale through integration of time...

Natural variations in calcium isotope composition as a monitor of bone mineral balance in humans.

Science.gov (United States)

Skulan, J.; Anbar, A.; Thomas, B.; Smith, S.

2004-12-01

The skeleton is the largest reservoir of calcium in the human body and is responsible for the short term control of blood levels of this element. Accurate measurement of changes in bone calcium balance is critical to understanding how calcium metabolism responds to physiological and environmental changes and, more specifically, to diagnosing and evaluating the effectiveness of treatments for osteoporosis and other serious calcium-related disorders. It is very difficult to measure bone calcium balance using current techniques, however, because these techniques rely either on separate estimates of bone resorption and formation that are not quantitatively comparable, or on complex and expensive studies of calcium kinetics using administered isotopic tracers. This difficulty is even more apparent and more severe for measurements of short-term changes in bone calcium balance that do not produce detectable changes in bone mineral density. Calcium isotopes may provide a novel means of addressing this problem. The foundation of this isotope application is the ca. 1.3 per mil fractionation of calcium during bone formation, favoring light calcium in the bone. This fractionation results in a steady-state isotopic offset between calcium in bone and calcium in soft tissues, blood and urine. Perturbations to this steady state due to changes in the net formation or resorption of bone should be reflected in changes in the isotopic composition of soft tissues and fluids. Here we present evidence that easily detectable shifts in the natural calcium isotope composition of human urine rapidly reflect changes in bone calcium balance. Urine from subjects in a 17-week bed rest study was analyzed for calcium isotopic composition. Bed rest promotes net resorption of bone, shifting calcium from bone to soft tissues, blood and urine. The calcium isotope composition of patients in this study shifted toward lighter values during bed rest, consistent with net resorption of isotopically

Patterns of nutrient utilization. Implications for nitrogen metabolism

International Nuclear Information System (INIS)

Oldham, J.D.

1983-01-01

Nutrients react within both the rumen and the ruminant body, and the patterns of availability of different nutrients greatly influence their net utilization. In the rumen, microbial capture of N substrates, especially ammonia, depends on the degree of synchronization between rates of production of N substrates and of ATP to drive microbial protein synthesis. The form of dietary carbohydrate and of dietary N and the frequency of feeding can all affect the efficiency of microbial growth and digestion. The pattern of supply of nutrients to the body will also influence nutrient utilization. Disparities between diurnal patterns of supply of volatile fatty acids from the rumen and amino acids from the intestines will result in changes in balance of metabolic pathways. The balance between supply of glucogenic and lipogenic nutrients will influence efficiency of fattening. A major factor determining the pattern of utilization/metabolism of amino acids is the metabolic demand for protein synthesis, which varies with physiological state. (author)

Understanding Regulation of Metabolism through Feasibility Analysis

Science.gov (United States)

Nikerel, Emrah; Berkhout, Jan; Hu, Fengyuan; Teusink, Bas; Reinders, Marcel J. T.; de Ridder, Dick

2012-01-01

Understanding cellular regulation of metabolism is a major challenge in systems biology. Thus far, the main assumption was that enzyme levels are key regulators in metabolic networks. However, regulation analysis recently showed that metabolism is rarely controlled via enzyme levels only, but through non-obvious combinations of hierarchical (gene and enzyme levels) and metabolic regulation (mass action and allosteric interaction). Quantitative analyses relating changes in metabolic fluxes to changes in transcript or protein levels have revealed a remarkable lack of understanding of the regulation of these networks. We study metabolic regulation via feasibility analysis (FA). Inspired by the constraint-based approach of Flux Balance Analysis, FA incorporates a model describing kinetic interactions between molecules. We enlarge the portfolio of objectives for the cell by defining three main physiologically relevant objectives for the cell: function, robustness and temporal responsiveness. We postulate that the cell assumes one or a combination of these objectives and search for enzyme levels necessary to achieve this. We call the subspace of feasible enzyme levels the feasible enzyme space. Once this space is constructed, we can study how different objectives may (if possible) be combined, or evaluate the conditions at which the cells are faced with a trade-off among those. We apply FA to the experimental scenario of long-term carbon limited chemostat cultivation of yeast cells, studying how metabolism evolves optimally. Cells employ a mixed strategy composed of increasing enzyme levels for glucose uptake and hexokinase and decreasing levels of the remaining enzymes. This trade-off renders the cells specialized in this low-carbon flux state to compete for the available glucose and get rid of over-overcapacity. Overall, we show that FA is a powerful tool for systems biologists to study regulation of metabolism, interpret experimental data and evaluate hypotheses. PMID

DNA Precursor Metabolism and Mitochondrial Genome Stability

National Research Council Canada - National Science Library

Mathews, Christopher K

2003-01-01

...) metabolism and mutagenesis in the mitochondrial genome. Specific contributions include: (1) We found that conditions altering the normal balance among the four dNTP pools within the mitochondrion stimulate both point and deletion mutagenesis...

Experimental study of self-balanced startup characteristics of density lock

International Nuclear Information System (INIS)

Gu Haifeng; Yan Changqi; Chen Wei

2013-01-01

With passive residual heat removal system which applies the density lock as background, combining the experimental study and theoretical analysis, researches on the operating characteristics and feasibility of self-balanced startup of density lock were made in this system. The results show that self-balanced startup can be divided into two stages: Warming up stage in which the valve is closed; self-balanced stage in which the valve is open. The two requisite conditions ensuring the closure of density lock can be realized respectively in these two stages, which ensure the separation of the passive residual heat removal system from the primary circuit system by the density lock. During the stage of warming up, with the help of special structure of the density lock, the position of the transition points of the heat transfer modes is controlled effectively, and the formation of interface between the cold and hot fluids is promoted. During the self-balanced stage, with the help of the characteristics of self-stability of the hydraulic balance, the motion of interface is controlled effectively, and the hydraulic balance is established automatically in the density lock. All of the results fully prove the feasibility of self-balanced startup. (authors)

Metabolism of 90Sr and of other elements in man, July 1, 1974--June 30, 1975

International Nuclear Information System (INIS)

1975-01-01

Trace element studies have been carried out under strictly controlled dietary conditions in adult males during different calcium intakes. Complete metabolic balances of cadmium, copper, zinc, lead, manganese, and nickel were determined in each 6-day metabolic period by analyzing the constant diet and the urinary and fecal excretions of these naturally occurring elements. In addition to the trace element studies, 85 Sr studies were carried out in man in order to complete previously initiated investigations

Once-per-step control of ankle-foot prosthesis push-off work reduces effort associated with balance during walking.

Science.gov (United States)

Kim, Myunghee; Collins, Steven H

2015-05-01

Individuals with below-knee amputation have more difficulty balancing during walking, yet few studies have explored balance enhancement through active prosthesis control. We previously used a dynamical model to show that prosthetic ankle push-off work affects both sagittal and frontal plane dynamics, and that appropriate step-by-step control of push-off work can improve stability. We hypothesized that this approach could be applied to a robotic prosthesis to partially fulfill the active balance requirements of human walking, thereby reducing balance-related activity and associated effort for the person using the device. We conducted experiments on human participants (N = 10) with simulated amputation. Prosthetic ankle push-off work was varied on each step in ways expected to either stabilize, destabilize or have no effect on balance. Average ankle push-off work, known to affect effort, was kept constant across conditions. Stabilizing controllers commanded more push-off work on steps when the mediolateral velocity of the center of mass was lower than usual at the moment of contralateral heel strike. Destabilizing controllers enforced the opposite relationship, while a neutral controller maintained constant push-off work regardless of body state. A random disturbance to landing foot angle and a cognitive distraction task were applied, further challenging participants' balance. We measured metabolic rate, foot placement kinematics, center of pressure kinematics, distraction task performance, and user preference in each condition. We expected the stabilizing controller to reduce active control of balance and balance-related effort for the user, improving user preference. The best stabilizing controller lowered metabolic rate by 5.5% (p = 0.003) and 8.5% (p = 0.02), and step width variability by 10.0% (p = 0.009) and 10.7% (p = 0.03) compared to conditions with no control and destabilizing control, respectively. Participants tended to prefer stabilizing controllers

Study books on ADHD genetics : balanced or biased?

NARCIS (Netherlands)

te Meerman, Sanne; Batstra, Laura; Hoekstra, Rink; Grietens, Hans

2017-01-01

Academic study books are essential assets for disseminating knowledge about ADHD to future healthcare professionals. This study examined if they are balanced with regard to genetics. We selected and analyzed study books (N=43) used in (pre) master's programmes at 10 universities in the Netherlands.

Metabolic profiles of cow's blood; a review.

Science.gov (United States)

Puppel, Kamila; Kuczyńska, Beata

2016-10-01

The term 'metabolic profile' refers to the analysis of blood biochemical parameters that are useful to assess and prevent metabolic and nutritional disorders in dairy herds. In the higher standards of milk production, the priority in modern breeding is keeping dairy cows in high lactation and healthy. The proper analysis, as well as control. of their feeding and metabolic status is immensely important for the health condition of the herd. The disproportion between the genetically determined ability for milk production and the limitations in improving the energy value of the ration may be the cause of metabolic disorders. Negative energy balance has a major impact on the body's hormonal balance and organ functions and mostly appears during transition periods: from 3 to 2 weeks prepartum until 2-3 weeks postpartum. The term 'transition' is used to underscore the important physiological, metabolic and nutritional changes occurring in this time. The manner in which these changes occur and how they are diagnosed and detected are extremely important, as they are closely related to clinical and subclinical postpartum diseases, lactation and reproductive performance - factors that significantly shape the profitability of production. Therefore the priority for intensive milk production is prevention of metabolic diseases and other disorders. It is the intent of this review to synthesize and summarize the information currently available on metabolic status and physiological changes in the cow's body that occur during lactation, as well as to discuss the interpretation of the results, which will be a useful diagnostic tool in nutritional evaluations of the dairy herd. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Emerging opportunities for the treatment of metabolic diseases

DEFF Research Database (Denmark)

Finan, Brian; Clemmensen, Christoffer; Müller, Timo D

2015-01-01

with integrated activities derived from multiple hormones involved in the physiological control of metabolism have emerged as one of the more promising candidates for reversing obesity. The inclusion of glucagon-like peptide-1 (GLP-1) as one of the constituents is a unifying factor amongst the majority......Obesity is a pathogenic gateway to the metabolic syndrome and the complications thereof, thus interventions aimed at preventing or reversing the metabolic derangements underlying obesity hold great therapeutic promise. However, the complexity of energy balance regulation, combined...

Relationships among personality traits, metabolic syndrome, and metabolic syndrome scores: The Kakegawa cohort study.

Science.gov (United States)

Ohseto, Hisashi; Ishikuro, Mami; Kikuya, Masahiro; Obara, Taku; Igarashi, Yuko; Takahashi, Satomi; Kikuchi, Daisuke; Shigihara, Michiko; Yamanaka, Chizuru; Miyashita, Masako; Mizuno, Satoshi; Nagai, Masato; Matsubara, Hiroko; Sato, Yuki; Metoki, Hirohito; Tachibana, Hirofumi; Maeda-Yamamoto, Mari; Kuriyama, Shinichi

2018-04-01

Metabolic syndrome and the presence of metabolic syndrome components are risk factors for cardiovascular disease (CVD). However, the association between personality traits and metabolic syndrome remains controversial, and few studies have been conducted in East Asian populations. We measured personality traits using the Japanese version of the Eysenck Personality Questionnaire (Revised Short Form) and five metabolic syndrome components-elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose-in 1322 participants aged 51.1±12.7years old from Kakegawa city, Japan. Metabolic syndrome score (MS score) was defined as the number of metabolic syndrome components present, and metabolic syndrome as having the MS score of 3 or higher. We performed multiple logistic regression analyses to examine the relationship between personality traits and metabolic syndrome components and multiple regression analyses to examine the relationship between personality traits and MS scores adjusted for age, sex, education, income, smoking status, alcohol use, and family history of CVD and diabetes mellitus. We also examine the relationship between personality traits and metabolic syndrome presence by multiple logistic regression analyses. "Extraversion" scores were higher in those with metabolic syndrome components (elevated waist circumference: P=0.001; elevated triglycerides: P=0.01; elevated blood pressure: P=0.004; elevated fasting glucose: P=0.002). "Extraversion" was associated with the MS score (coefficient=0.12, P=0.0003). No personality trait was significantly associated with the presence of metabolic syndrome. Higher "extraversion" scores were related to higher MS scores, but no personality trait was significantly associated with the presence of metabolic syndrome. Copyright © 2018 Elsevier Inc. All rights reserved.

Environmental and genetic effects on tomato seed metabolic balance and its association with germination vigor.

Science.gov (United States)

Rosental, Leah; Perelman, Adi; Nevo, Noa; Toubiana, David; Samani, Talya; Batushansky, Albert; Sikron, Noga; Saranga, Yehoshua; Fait, Aaron

2016-12-19

The metabolite content of a seed and its ability to germinate are determined by genetic makeup and environmental effects during development. The interaction between genetics, environment and seed metabolism and germination was studied in 72 tomato homozygous introgression lines (IL) derived from Solanum pennelli and S. esculentum M82 cultivar. Plants were grown in the field under saline and fresh water irrigation during two consecutive seasons, and collected seeds were subjected to morphological analysis, gas chromatograph-mass spectrometry (GC-MS) metabolic profiling and germination tests. Seed weight was under tight genetic regulation, but it was not related to germination vigor. Salinity significantly reduced seed number but had little influence on seed metabolites, affecting only 1% of the statistical comparisons. The metabolites negatively correlated to germination were simple sugars and most amino acids, while positive correlations were found for several organic acids and the N metabolites urea and dopamine. Germination tests identified putative loci for improved germination as compared to M82 and in response to salinity, which were also characterized by defined metabolic changes in the seed. An integrative analysis of the metabolite and germination data revealed metabolite levels unambiguously associated with germination percentage and rate, mostly conserved in the different tested seed development environments. Such consistent relations suggest the potential for developing a method of germination vigor prediction by metabolic profiling, as well as add to our understanding of the importance of primary metabolic processes in germination.

Dancing for Healthy Aging: Functional and Metabolic Perspectives.

Science.gov (United States)

Rodrigues-Krause, Josianne; Krause, Mauricio; Reischak-Oliveira, Alvaro

2018-02-10

); (3) aerobic dance with no partner required, which mixes aerobic moves with dance moves; (4) dance therapies, whichare special dance programs including emotional and physical aspects; and (5) classical dances, which are dances with a unique tradition and technique, such as ballet or jazz dance. Outcome Measures • Studies needed to have evaluated functional and/or metabolic outcomes. Functional outcomes included (1) static and/or dynamic balance, (2) gait ability, (3) upper and/or lower muscle strength or power, (4) cardiorespiratory fitness, (5) flexibility, (6) risk of falls, and (7) quality of life. Metabolic outcomes included (1) lipid and glycemic profile; (2) systolic and diastolic blood pressure; (3) body composition; and (4) other specific cardiovascular risk factors or inflammatory or oxidative stress markers. Results • The research team retrieved 1042 articles, with 88 full texts assessed for eligibility, and 50 articles included in the analysis. Of the analyzed studies, 22 were RCTs evaluating dancing vs controls, and 3 were RCTs evaluating dancing vs other exercise. Regarding the participants of the reviewed studies: (1) 31 evaluated healthy individuals, (2) 7 evaluated patients suffering from Parkinson's disease, (3) 4 evaluated postmenopausal women, (4) 2 evaluated obese women, (5) 2 evaluated patients with chronic heart failure, (6) 1 evaluated frail older adults, (7) 1 evaluated individuals with visual impairments, (8) 1 evaluated persons with metabolic syndrome, and (9) 1 evaluated individuals with severe pain in the lower extremities. Regarding the interventions, most interventions were 12 wk long, 3 ×/wk, for 60 min each session. The dance styles most used were ballroom and cultural dances. Regarding the outcomes, functional and metabolic benefits were described in most of the included studies. Balance was the functional outcome most often assessed. Conclusions • Any dance style can induce positive functional adaptations in older adults

Association of sleep quality components and wake time with metabolic syndrome: The Qazvin Metabolic Diseases Study (QMDS), Iran.

Science.gov (United States)

Zohal, Mohammadali; Ghorbani, Azam; Esmailzadehha, Neda; Ziaee, Amir; Mohammadi, Zahrasadat

2017-11-01

The aim of this study was to determine the association of sleep quality and sleep quantity with metabolic syndrome in Qazvin, Iran. this cross sectional study was conducted in 1079 residents of Qazvin selected by multistage cluster random sampling method in 2011. Metabolic syndrome was defined according to the criteria proposed by the national cholesterol education program third Adult treatment panel. Sleep was assessed using the Pittsburgh sleep quality index (PSQI). A logistic regression analysis was used to examine the association of sleep status and metabolic syndrome. Mean age was 40.08±10.33years. Of 1079, 578 (52.2%) were female, and 30.6% had metabolic syndrome. The total global PSQI score in the subjects with metabolic syndrome was significantly higher than subjects without metabolic syndrome (6.30±3.20 vs. 5.83±2.76, P=0.013). In logistic regression analysis, sleep disturbances was associated with 1.388 fold increased risk of metabolic syndrome after adjustment for age, gender, and body mass index. Sleep disturbances component was a predictor of metabolic syndrome in the present study. More longitudinal studies are necessary to understand the association of sleep quality and its components with metabolic syndrome. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Effects of Dietary Electrolyte Balance on Growth Performance, Nitrogen Metabolism and Some Blood Biochemical Parameters of Growing Rabbits

Directory of Open Access Journals (Sweden)

J. W. Li

2013-12-01

Full Text Available The effects of different dietary electrolyte balance (DEB on growth performance, nitrogen (N metabolism and some blood biochemical parameters were investigated in 2 to 3 months old growing rabbits. A total of 150 growing rabbits of 2 months age were randomly divided into five groups according to average body weight, with 30 rabbits in each group. The DEB levels of the five experimental diets were −154, −3.16, +201, +347, and +500 meq/kg of dry matter (DM, respectively. There was a 7-d adaptation period and a 23-d experimental period. The results showed that the DEB levels had a quadratic affect on the average daily feed intake (ADFI (p<0.001. The greatest ADFI was achieved when the DEB level was +201 meq/kg DM. Fecal N (FN content linearly decreased (0.047, while digestible N (DN, retained N (RN, efficiency of intake N converted into digestible N (DN/IN and the efficiency of intake N converted into retained N (RN/IN linearly increased with the DEB increase (0.020, 0.004, 0.021, and 0.049, respectively. Serum phosphorus (P ion content linearly increased with the DEB increase (p = 0.036. The DEB had a quadratic relationship with serum anion gap (AG (p = 0.002 and serum parathyroid hormone (PTH content (p = 0.016. The DEB levels quadratically affected base excess (BE in the plasma (p<0.001. In conclusion, the DEB unaffected growth performance but affected feed intake, N metabolism and some blood biochemical parameters of growing rabbits.

Analyzing redox balance in a synthetic yeast platform to improve utilization of brown macroalgae as feedstock

Directory of Open Access Journals (Sweden)

C.A. Contador

2015-12-01

Full Text Available Macroalgae have high potential to be an efficient, and sustainable feedstock for the production of biofuels and other more valuable chemicals. Attempts have been made to enable the co-fermentation of alginate and mannitol by Saccharomyces cerevisiae to unlock the full potential of this marine biomass. However, the efficient use of the sugars derived from macroalgae depends on the equilibrium of cofactors derived from the alginate and mannitol catabolic pathways. There are a number of strong metabolic limitations that have to be tackled before this bioconversion can be carried out efficiently by engineered yeast cells.An analysis of the redox balance during ethanol fermentation from alginate and mannitol by Saccharomyces cerevisiae using metabolic engineering tools was carried out. To represent the strain designed for conversion of macroalgae carbohydrates to ethanol, a context-specific model was derived from the available yeast genome-scale metabolic reconstructions. Flux balance analysis and dynamic simulations were used to determine the flux distributions. The model indicates that ethanol production is determined by the activity of 4-deoxy-l-erythro-5-hexoseulose uronate (DEHU reductase (DehR and its preferences for NADH or NADPH which influences strongly the flow of cellular resources. Different scenarios were explored to determine the equilibrium between NAD(H and NADP(H that will lead to increased ethanol yields on mannitol and DEHU under anaerobic conditions. When rates of mannitol dehydrogenase and DehRNADH tend to be close to a ratio in the range 1–1.6, high growth rates and ethanol yields were predicted. The analysis shows a number of metabolic limitations that are not easily identified through experimental procedures such as quantifying the impact of the cofactor preference by DEHU reductase in the system, the low flux into the alginate catabolic pathway, and a detailed analysis of the redox balance. These results show that

Investigation of bone and mineral metabolism in hyperthyroidism before and after treatment using calcitonin, /sup 47/Ca and balance studies

Energy Technology Data Exchange (ETDEWEB)

Hendriks, J Th.A.M. [Department of Internal Medicine, St. Franciscus Hospital, 4708 AE Roosendaal, The Netherlands; Smeenk, D [Department of Endocrinology, University Hospital, 2333 AA Leiden, The Netherlands

1979-01-01

Seventeen normocalcaemic patients with severe hyperthyroidism were examined before therapy was initiated; 9 were re-examined about 1 year later. Studies with /sup 47/Ca under balance conditions and with calcitonin demonstrated a high rate of bone resorption in untreated patients. As a result of the increased bone turnover, the reaction to 6 MRC units of porcine calcitonin iv was more marked in the untreated than in the treated patients, or the control group. In contrast to the normal diurnal pattern for PO/sub 4/, it was found that during fasting the plasma PO/sub 4/ level increases in the morning in patients with hyperthyroidism. This increase which was not suppressed by the administered dose of calcitonin developed in spite of an elevated urinary PO/sub 4/ excretion. After treatment, the serum Ca concentration as well as the urinary and faecal Ca excretion was decreased. The Ca balance improved; the rapidly-exchangeable Ca pool returned to normal. The slowly-exchangeable and the total Ca pools, however, remained enlarged. The rate of bone resorption normalized. The accretion rate on the other hand remained elevated. This is attributed to continued enhancement of bone formation to compensate for the previous loss of bony tissue.

[Modifications in myocardial energy metabolism in diabetic patients

Science.gov (United States)

Grynberg, A

2001-11-01

The capacity of cardiac myocyte to regulate ATP production to face any change in energy demand is a major determinant of cardiac function. Because FA is the main heart fuel (although the most expensive one in oxygen, and prompt to induce deleterious effects), this process is based on a balanced fatty acid (FA) metabolism. Several pathological situations are associated with an accumulation of FA or derivatives, or with an excessive b-oxidation. The diabetic cardiomyocyte is characterised by an over consumption of FA. The control of the FA/glucose balance clearly appears as a new strategy for cytoprotection, particularly in diabetes and requires a reduced FA contribution to ATP production. Cardiac myocytes can control FA mitochondrial entry, but display weak ability to control FA uptake, thus the fate of non beta-oxidized FA appear as a new impairment for the cell. Both the trigger and the regulation of cardiac contraction result from membrane activity, and the other major FA function in the myocardium is their role in membrane homeostasis, through the phospholipid synthesis and remodeling pathways. Sudden death, hypercatecholaminemia, diabetes and heart failure have been associated with an altered PUFA content in cardiac membranes. Experimental data suggest that the 2 metabolic pathways involved in membrane homeostasis may represent therapeutic targets for cytoprotection. The drugs that increase cardiac phospholipid turnover (trimétazidine, ranolazine,...) display anti-ischemic non hemodynamic effect. This effect is based on a redirection of FA utilization towards phospholipid synthesis, which decrease their availability for energy production. A nutritional approach gave also promising results. Besides its anti-arrhythmic effect, the dietary docosahexaenoic acid is able to reduce FA energy consumption and hence oxygen demand. The cardiac metabolic pathways involving FA should be considered as a whole, precariously balanced. The diabetic heart being characterised by

A cross-national study on the antecedents of work–life balance from the fit and balance perspective

OpenAIRE

Haar, Jarrod M.; Suñé Torrents, Albert; Russo, Marcello; Ollier-Malaterre, Ariane

2018-01-01

Drawing on the perceived work–family fit and balance perspective, this study investigates demands and resources as antecedents of work–life balance (WLB) across four countries (New Zealand, France, Italy and Spain), so as to provide empirical cross-national evidence. Using structural equation modelling analysis on a sample of 870 full time employees, we found that work demands, hours worked and family demands were negatively related to WLB, while job autonomy and supervisor support were posit...

Mechanisms and significance of brain glucose signaling in energy balance, glucose homeostasis, and food-induced reward.

Science.gov (United States)

Devarakonda, Kavya; Mobbs, Charles V

2016-12-15

The concept that hypothalamic glucose signaling plays an important role in regulating energy balance, e.g., as instantiated in the so-called "glucostat" hypothesis, is one of the oldest in the field of metabolism. However the mechanisms by which neurons in the hypothalamus sense glucose, and the function of glucose signaling in the brain, has been difficult to establish. Nevertheless recent studies probing mechanisms of glucose signaling have also strongly supported a role for glucose signaling in regulating energy balance, glucose homeostasis, and food-induced reward. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Interdependence of nutrient metabolism and the circadian clock system: Importance for metabolic health

Science.gov (United States)

Ribas-Latre, Aleix; Eckel-Mahan, Kristin

2016-01-01

Background While additional research is needed, a number of large epidemiological studies show an association between circadian disruption and metabolic disorders. Specifically, obesity, insulin resistance, cardiovascular disease, and other signs of metabolic syndrome all have been linked to circadian disruption in humans. Studies in other species support this association and generally reveal that feeding that is not in phase with the external light/dark cycle, as often occurs with night or rotating shift workers, is disadvantageous in terms of energy balance. As food is a strong driver of circadian rhythms in the periphery, understanding how nutrient metabolism drives clocks across the body is important for dissecting out why circadian misalignment may produce such metabolic effects. A number of circadian clock proteins as well as their accessory proteins (such as nuclear receptors) are highly sensitive to nutrient metabolism. Macronutrients and micronutrients can function as zeitgebers for the clock in a tissue-specific way and can thus impair synchrony between clocks across the body, or potentially restore synchrony in the case of circadian misalignment. Circadian nuclear receptors are particularly sensitive to nutrient metabolism and can alter tissue-specific rhythms in response to changes in the diet. Finally, SNPs in human clock genes appear to be correlated with diet-specific responses and along with chronotype eventually may provide valuable information from a clinical perspective on how to use diet and nutrition to treat metabolic disorders. Scope of review This article presents a background of the circadian clock components and their interrelated metabolic and transcriptional feedback loops, followed by a review of some recent studies in humans and rodents that address the effects of nutrient metabolism on the circadian clock and vice versa. We focus on studies in which results suggest that nutrients provide an opportunity to restore or, alternatively

Impaired osteoblast function in osteoporosis: comparison between calcium balance and dynamic histomorphometry.

OpenAIRE

Arlot, M; Edouard, C; Meunier, P J; Neer, R M; Reeve, J

1984-01-01

Osteoblast function was investigated in 27 patients with idiopathic osteoporosis. Transiliac bone biopsy specimens were taken after double labelling with tetracycline, and metabolic calcium balance was studied almost simultaneously. Many of the patients showed poor double labelling of their otherwise unremarkable trabecular osteoid, suggesting impaired formation of bone at many of these surfaces. This phenomenon was not accompanied by increased width of osteoid seams (as seen in osteomalacia)...

Metabolism and binding to DNA of a novel hepatocarcinogen: methapyrilene

International Nuclear Information System (INIS)

Lampe, M.A.

1987-01-01

The purpose of this study was to characterize the metabolism and macromolecular binding of [ 14 C]-MPH. When rats were treated for up to sixteen weeks with 1000 ppm MPH, they excreted at least six MPH related compounds in their urine including 2-hydroxymethyl-thiophene, N-2-pyridyl-N'-dimethylethylenediamine, (5-hydroxypyridyl)methapyrilene, (5-hydroxypyridyl)N-2-pyridyl-N'-dimethylethylenediamine and MPH. In vitro metabolism is also affected by chronic treatment of rats with MPH, with the most remarkable change observed being an increase in the mass balance to approximately 100% after 8 or 16 weeks pretreatment. Metabolism of MPH by rat liver microsomes is dependent on the activity of cytochrome P-450 enzymes, as metabolism in vitro was inhibited by the addition 2,4-dichloro-6-phenylphenoxyethylamine (DPEA) and 2-diethylaminoethyl-2,2-diphenylvalerate (SKF-525A). Treatment of rats with phenobarbital or 3-methylcholanthrene induced metabolism of MPH while pretreatment of rats with isosafole or pregnenolone-16α-carbonitrile had a more selective effect on MPH metabolism, and only increased the formation of methapyrilene-amide

Understanding specificity in metabolic pathways-Structural biology of human nucleotide metabolism

International Nuclear Information System (INIS)

Welin, Martin; Nordlund, Paer

2010-01-01

Interactions are the foundation of life at the molecular level. In the plethora of activities in the cell, the evolution of enzyme specificity requires the balancing of appropriate substrate affinity with a negative selection, in order to minimize interactions with other potential substrates in the cell. To understand the structural basis for enzyme specificity, the comparison of structural and biochemical data between enzymes within pathways using similar substrates and effectors is valuable. Nucleotide metabolism is one of the largest metabolic pathways in the human cell and is of outstanding therapeutic importance since it activates and catabolises nucleoside based anti-proliferative drugs and serves as a direct target for anti-proliferative drugs. In recent years the structural coverage of the enzymes involved in human nucleotide metabolism has been dramatically improved and is approaching completion. An important factor has been the contribution from the Structural Genomics Consortium (SGC) at Karolinska Institutet, which recently has solved 33 novel structures of enzymes and enzyme domains in human nucleotide metabolism pathways and homologs thereof. In this review we will discuss some of the principles for substrate specificity of enzymes in human nucleotide metabolism illustrated by a selected set of enzyme families where a detailed understanding of the structural determinants for specificity is now emerging.

Work-Life Balance: A Study In The Petroleum Industry

OpenAIRE

Judy De Villiers; Elize Kotze

2003-01-01

A qualitative study was completed to discover how employees of a company in the petroleum industry define and experience the phenomenon of work-life balance, to identify the workplace determinants of work-life imbalance and to elicit some solutions for the problem. It was found that work-life balance is a personal issue that varies across time and situations and the underlying conflict experienced pertains to role overload and role interference. The most significant work-life conflict arises ...

The interaction between nutrition and metabolism in West African dwarf goats, infected with trypanosomes

NARCIS (Netherlands)

Dam, van J.T.P.

1996-01-01

In a series of experiments the interaction between nutrition and energy- and nitrogen metabolism of West African Dwarf goats, infected with trypanosomes was studied. Animals were injected with trypanosomes, and feed intake, energy and nitrogen balance and blood metabolites and hormones were measured

Genome-scale modeling using flux ratio constraints to enable metabolic engineering of clostridial metabolism in silico.

Science.gov (United States)

McAnulty, Michael J; Yen, Jiun Y; Freedman, Benjamin G; Senger, Ryan S

2012-05-14

Genome-scale metabolic networks and flux models are an effective platform for linking an organism genotype to its phenotype. However, few modeling approaches offer predictive capabilities to evaluate potential metabolic engineering strategies in silico. A new method called "flux balance analysis with flux ratios (FBrAtio)" was developed in this research and applied to a new genome-scale model of Clostridium acetobutylicum ATCC 824 (iCAC490) that contains 707 metabolites and 794 reactions. FBrAtio was used to model wild-type metabolism and metabolically engineered strains of C. acetobutylicum where only flux ratio constraints and thermodynamic reversibility of reactions were required. The FBrAtio approach allowed solutions to be found through standard linear programming. Five flux ratio constraints were required to achieve a qualitative picture of wild-type metabolism for C. acetobutylicum for the production of: (i) acetate, (ii) lactate, (iii) butyrate, (iv) acetone, (v) butanol, (vi) ethanol, (vii) CO2 and (viii) H2. Results of this simulation study coincide with published experimental results and show the knockdown of the acetoacetyl-CoA transferase increases butanol to acetone selectivity, while the simultaneous over-expression of the aldehyde/alcohol dehydrogenase greatly increases ethanol production. FBrAtio is a promising new method for constraining genome-scale models using internal flux ratios. The method was effective for modeling wild-type and engineered strains of C. acetobutylicum.

Protocols to Study Growth and Metabolism in Drosophila.

Science.gov (United States)

Strassburger, Katrin; Teleman, Aurelio A

2016-01-01

Signaling pathways such as the insulin/insulin-like growth factor pathway concurrently regulate organismal growth and metabolism. Drosophila has become a popular model system for studying both organismal growth and metabolic regulation. Care must be taken, however, when assessing such phenotypes because they are quantitative in nature, and influenced by environment. This chapter first describes how to control animal age and nutrient availability, since growth and metabolism are sensitive to these parameters. It then provides protocols for measuring tissue growth, cell size, and metabolic parameters such as stored lipids and glycogen, and circulating sugars.

Metabolic disorders in menopause

Directory of Open Access Journals (Sweden)

Grzegorz Stachowiak

2015-04-01

Full Text Available Metabolic disorders occurring in menopause, including dyslipidemia, disorders of carbohydrate metabolism (impaired glucose tolerance – IGT, type 2 diabetes mellitus – T2DM or components of metabolic syndrome, constitute risk factors for cardiovascular disease in women. A key role could be played here by hyperinsulinemia, insulin resistance and visceral obesity, all contributing to dyslipidemia, oxidative stress, inflammation, alter coagulation and atherosclerosis observed during the menopausal period. Undiagnosed and untreated, metabolic disorders may adversely affect the length and quality of women’s life. Prevention and treatment preceded by early diagnosis should be the main goal for the physicians involved in menopausal care. This article represents a short review of the current knowledge concerning metabolic disorders (e.g. obesity, polycystic ovary syndrome or thyroid diseases in menopause, including the role of a tailored menopausal hormone therapy (HT. According to current data, HT is not recommend as a preventive strategy for metabolic disorders in menopause. Nevertheless, as part of a comprehensive strategy to prevent chronic diseases after menopause, menopausal hormone therapy, particularly estrogen therapy may be considered (after balancing benefits/risks and excluding women with absolute contraindications to this therapy. Life-style modifications, with moderate physical activity and healthy diet at the forefront, should be still the first choice recommendation for all patients with menopausal metabolic abnormalities.

Hypothalamic carnitine metabolism integrates nutrient and hormonal feedback to regulate energy homeostasis.

Science.gov (United States)

Stark, Romana; Reichenbach, Alex; Andrews, Zane B

2015-12-15

The maintenance of energy homeostasis requires the hypothalamic integration of nutrient feedback cues, such as glucose, fatty acids, amino acids, and metabolic hormones such as insulin, leptin and ghrelin. Although hypothalamic neurons are critical to maintain energy homeostasis research efforts have focused on feedback mechanisms in isolation, such as glucose alone, fatty acids alone or single hormones. However this seems rather too simplistic considering the range of nutrient and endocrine changes associated with different metabolic states, such as starvation (negative energy balance) or diet-induced obesity (positive energy balance). In order to understand how neurons integrate multiple nutrient or hormonal signals, we need to identify and examine potential intracellular convergence points or common molecular targets that have the ability to sense glucose, fatty acids, amino acids and hormones. In this review, we focus on the role of carnitine metabolism in neurons regulating energy homeostasis. Hypothalamic carnitine metabolism represents a novel means for neurons to facilitate and control both nutrient and hormonal feedback. In terms of nutrient regulation, carnitine metabolism regulates hypothalamic fatty acid sensing through the actions of CPT1 and has an underappreciated role in glucose sensing since carnitine metabolism also buffers mitochondrial matrix levels of acetyl-CoA, an allosteric inhibitor of pyruvate dehydrogenase and hence glucose metabolism. Studies also show that hypothalamic CPT1 activity also controls hormonal feedback. We hypothesis that hypothalamic carnitine metabolism represents a key molecular target that can concurrently integrate nutrient and hormonal information, which is critical to maintain energy homeostasis. We also suggest this is relevant to broader neuroendocrine research as it predicts that hormonal signaling in the brain varies depending on current nutrient status. Indeed, the metabolic action of ghrelin, leptin or insulin

An open circuit balance respirometer for bioenergetic studies of fish growth

NARCIS (Netherlands)

Hogendoorn, H.; Korlaar, van F.; Bosch, H.

1981-01-01

A description is given of an open circuit balance respirometer for bioenergetic studies of fish growth using indirect calorimetry. The installation was designed to enable the determination of gas and matter balances of fish, including air breathing species, during prolonged experimental periods.

Gout and Metabolic Syndrome: a Tangled Web.

Science.gov (United States)

Thottam, Gabrielle E; Krasnokutsky, Svetlana; Pillinger, Michael H

2017-08-26

The complexity of gout continues to unravel with each new investigation. Gout sits at the intersection of multiple intrinsically complex processes, and its prevalence, impact on healthcare costs, and association with important co-morbidities make it increasingly relevant. The association between gout and type 2 diabetes, hypertension, hyperlipidemia, cardiovascular disease, renal disease, and obesity suggest that either gout, or its necessary precursor hyperuricemia, may play an important role in the manifestations of the metabolic syndrome. In this review, we analyze the complex interconnections between gout and metabolic syndrome, by reviewing gout's physiologic and epidemiologic relationships with its major co-morbidities. Increasing evidence supports gout's association with metabolic syndrome. More specifically, both human studies and animal models suggest that hyperuricemia may play a role in promoting inflammation, hypertension and cardiovascular disease, adipogenesis and lipogenesis, insulin and glucose dysregulation, and liver disease. Fructose ingestion is associated with increased rates of hypertension, weight gain, impaired glucose tolerance, and dyslipidemia and is a key driver of urate biosynthesis. AMP kinase (AMPK) is a central regulator of processes that tend to mitigate against the metabolic syndrome. Within hepatocytes, leukocytes, and other cells, a fructose/urate metabolic loop drives key inhibitors of AMPK, including AMP deaminase and fructokinase, that may tilt the balance toward metabolic syndrome progression. Preliminary evidence suggests that agents that block the intracellular synthesis of urate may restore AMPK activity and help maintain metabolic homeostasis. Gout is both an inflammatory and a metabolic disease. With further investigation of urate's role, the possibility of proper gout management additionally mitigating metabolic syndrome is an evolving and important question.

Assistive devices for balance and mobility: benefits, demands, and adverse consequences.

Science.gov (United States)

Bateni, Hamid; Maki, Brian E

2005-01-01

To provide information on the advantages and possible disadvantages of using canes and walkers. English-language articles were identified by searching MEDLINE and PubMed (1966-May 2003) for key words cane or walker , excluding articles unrelated to mobility aids. Bibliographies were reviewed and ISI Web of Science citation searches were run to identify additional references. Over 1000 articles were selected for further evaluation. We extracted all studies of single-tip canes or pickup walkers addressing: (1) functional, biomechanic, or neuromotor benefits; (2) biomechanic, attentional, neuromotor, metabolic, or physiologic demands; and (3) falls, injuries, or other problems. We included approximately 10% of the articles originally identified. The methodology of each selected article, and findings relevant to the benefits, demands, or adverse effects of cane or walker use were summarized. Findings were synthesized by considering their relation to basic biomechanic principles. Some biomechanic findings appear to support the clinical view that canes and walkers can improve balance and mobility for older adults and people with other clinical conditions. However, a large proportion of users experience difficulties, and the use of such devices is associated with increased risk of falling. A small number of studies have characterized some of the specific demands and problems associated with using mobility aids. Clinical and biomechanic evaluations of canes and walkers confirm that these devices can improve balance and mobility. However, they can also interfere with ones ability to maintain balance in certain situations, and the strength and metabolic demands can be excessive. More research is needed to identify and solve specific problems. Such research may lead to improved designs and guidelines for safer use of canes and walkers.

Dietary Whey and Casein Differentially Affect Energy Balance, Gut Hormones, Glucose Metabolism, and Taste Preference in Diet-Induced Obese Rats.

Science.gov (United States)

Pezeshki, Adel; Fahim, Andrew; Chelikani, Prasanth K

2015-10-01

Dietary whey and casein proteins decrease food intake and body weight and improve glycemic control; however, little is known about the underlying mechanisms. We determined the effects of dietary whey, casein, and a combination of the 2 on energy balance, hormones, glucose metabolism, and taste preference in rats. In Expt. 1, Obesity Prone CD (OP-CD) rats were fed a high-fat control diet (33% fat energy) for 8 wk, and then randomly assigned to 4 isocaloric dietary treatments (n = 12/group): the control treatment (CO; 14% protein energy from egg white), the whey treatment (WH; 26% whey + 14% egg white), the casein treatment (CA; 26% casein + 14% egg white), or the whey plus casein treatment (WHCA; 13% whey + 13% casein + 14% egg white) for 28 d. Measurements included food intake, energy expenditure, body composition, metabolic hormones, glucose tolerance and key tissue markers of glucose and energy metabolism. In Expt. 2, naïve OP-CD rats were randomly assigned to 3 groups (n = 8/group). During an 8 d conditioning period, each group received on alternate days either the CO or WH, CO or CA, or CO or WHCA. Subsequently, preferences for the test diets were assessed on 2 consecutive days with food intake measurements at regular intervals. In Expt. 1, food intake was decreased by 17-37% for the first 14 d in the WH and CA rats, and by 18-34% only for the first 4 d in the WHCA compared with the CO rats. Fat mass decreased by 21-28% for the WH rats and 17-33% for the CA rats from day 14 onward, but by 30% only on day 28 in WHCA rats, relative to CO rats. Thus, food intake, body weight, and fat mass decreased more rapidly in WH and CA rats than in WHCA rats. Energy expenditure in WH rats decreased for the first 4 d compared with CA and WHCA rats, and for the first 7 d compared with the CO rats. Circulating leptin, glucose-dependent insulinotropic polypeptide, interleukin 6, and glucose concentrations were lower in WH, CA, and WHCA rats than in CO rats. Plasma glucagon

Flux balance analysis of genome-scale metabolic model of rice ...

Indian Academy of Sciences (India)

2015-09-28

Sep 28, 2015 ... biologists are also trying to understand the plant's systems level biochemistry ... metabolism to observe the effect of intracellular transporters' transport ..... [The information about this pathway and associated genes in .... 2013 A method for accounting for mainte- ... Biological control of rice diseases pp 1–11.

Mitochondrial protein acetylation mediates nutrient sensing of mitochondrial protein synthesis and mitonuclear protein balance.

Science.gov (United States)

Di Domenico, Antonella; Hofer, Annette; Tundo, Federica; Wenz, Tina

2014-11-01

Changes in nutrient supply require global metabolic reprogramming to optimize the utilization of the nutrients. Mitochondria as a central component of the cellular metabolism play a key role in this adaptive process. Since mitochondria harbor their own genome, which encodes essential enzymes, mitochondrial protein synthesis is a determinant of metabolic adaptation. While regulation of cytoplasmic protein synthesis in response to metabolic challenges has been studied in great detail, mechanisms which adapt mitochondrial translation in response to metabolic challenges remain elusive. Our results suggest that the mitochondrial acetylation status controlled by Sirt3 and its proposed opponent GCN5L1 is an important regulator of the metabolic adaptation of mitochondrial translation. Moreover, both proteins modulate regulators of cytoplasmic protein synthesis as well as the mitonuclear protein balance making Sirt3 and GCN5L1 key players in synchronizing mitochondrial and cytoplasmic translation. Our results thereby highlight regulation of mitochondrial translation as a novel component in the cellular nutrient sensing scheme and identify mitochondrial acetylation as a new regulatory principle for the metabolic competence of mitochondrial protein synthesis. © 2014 International Union of Biochemistry and Molecular Biology.

T55 power turbine rotor multiplane-multispeed balancing study

Science.gov (United States)

Martin, M. R.

1982-01-01

A rotordynamic analysis of the T55-L-11C engine was used to evaluate the balancing needs of the power turbine and to optimize the balancing procedure. As a result, recommendations were made for implementation of a multiplane-multispeed balancing plan. Precision collars for the attachment of trial weights to a slender rotor were designed enabling demonstration balancing on production hardware. The quality of the balance was then evaluated by installing a high speed balanced power turbine in an engine and running in a test cell at the Corpus Christi Army depot. The engine used had been tested prior to the turbine changeout and showed acceptable overall vibration levels for the engine were significantly reduced, demonstrating the ability of multiplane-multispeed balancing to control engine vibration.

Using motor imagery to study the neural substrates of dynamic balance

NARCIS (Netherlands)

Ferraye, M.U.; Debû, B.H.G.; Heil, L.; Carpenter, M.; Bloem, B.R.; Toni, I.

2014-01-01

This study examines the cerebral structures involved in dynamic balance using a motor imagery (MI) protocol. We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined swaying on a balance board along the sagittal plane to point a laser at target pairs of

Analysis of temperature-dependent changes in the metabolism of Yersinia pestis.

Science.gov (United States)

Navid, Ali; Almaas, Eivind

2008-03-01

The gram-negative bacterium Yersinia pestis is the aetiological agent of bubonic plague, a zoonotic infection that occurs through the bite of a flea. It has long been known that Y. pestis has different metabolic needs upon transition from the flea gut environment (26 C) to that of a mammalian host (37 C). To study this and other outstanding questions about metabolic function of Y. pestis, we used the available genomic, biochemical and physiological data to develop a constraint-based flux balance model of metabolism in the avirulent 91001 strain (biovar Mediaevalis) of this organism. Utilizing two sets of whole-genome DNA microarray expression data, we examined the system level changes that occur when Y. pestis acclimatizes to temperature shifts. Our results point to fundamental changes in its oxidative metabolism of sugars and use of amino acids, in particular that of arginine. This behavior is indicative of an inefficient metabolism that could be caused by adaptation to life in a nutrient rich environment.

Regulation of uric acid metabolism and excretion.

Science.gov (United States)

Maiuolo, Jessica; Oppedisano, Francesca; Gratteri, Santo; Muscoli, Carolina; Mollace, Vincenzo

2016-06-15

Purines perform many important functions in the cell, being the formation of the monomeric precursors of nucleic acids DNA and RNA the most relevant one. Purines which also contribute to modulate energy metabolism and signal transduction, are structural components of some coenzymes and have been shown to play important roles in the physiology of platelets, muscles and neurotransmission. All cells require a balanced quantity of purines for growth, proliferation and survival. Under physiological conditions the enzymes involved in the purine metabolism maintain in the cell a balanced ratio between their synthesis and degradation. In humans the final compound of purines catabolism is uric acid. All other mammals possess the enzyme uricase that converts uric acid to allantoin that is easily eliminated through urine. Overproduction of uric acid, generated from the metabolism of purines, has been proven to play emerging roles in human disease. In fact the increase of serum uric acid is inversely associated with disease severity and especially with cardiovascular disease states. This review describes the enzymatic pathways involved in the degradation of purines, getting into their structure and biochemistry until the uric acid formation. Copyright © 2015. Published by Elsevier Ireland Ltd.

Application Study of Self-balanced Testing Method on Big Diameter Rock-socketed Piles

Directory of Open Access Journals (Sweden)

Qing-biao WANG

2013-07-01

Full Text Available Through the technological test of self-balanced testing method on big diameter rock-socketed piles of broadcasting centre building of Tai’an, this paper studies and analyzes the links of the balance position selection, the load cell production and installation, displacement sensor selection and installation, loading steps, stability conditions and determination of the bearing capacity in the process of self-balanced testing. And this paper summarizes key technology and engineering experience of self-balanced testing method of big diameter rock-socketed piles and, meanwhile, it also analyzes the difficult technical problems needed to be resolved urgently at present. Conclusion of the study has important significance to the popularization and application of self-balanced testing method and the similar projects.

Effects of Tai Chi Chuan on the elderly balance: a semi-experimental study

OpenAIRE

Konig,Pablo Rafael; Galarza,Eveline; Goulart,Natália Batista Albuquerque; Lanferdini,Fábio Juner; Tiggeman,Carlos Leandro; Dias,Caroline Pieta

2014-01-01

Aging impairs the functional capacity, possibly compromising the balance over the years. However, Tai Chi Chuan is a martial art that can provide balance improvements in elderly people. This study aimed to evaluate balance in elderly after three and six months of Tai Chi Chuan practicing. Participants were 27 individuals (62±4.4 years) who underwent Tai Chi Chuan training (one hour each) twice a week, for six months. Balance was assessed by the Timed Up and Go (TUG) test, Berg Balance Sc...

Effects of Tai Chi Chuan on the elderly balance: a semi-experimental study

OpenAIRE

Konig, Pablo Rafael; Galarza, Eveline; Goulart, Natália Batista Albuquerque; Lanferdini, Fábio Juner; Tiggeman, Carlos Leandro; Dias, Caroline Pieta

2014-01-01

Aging impairs the functional capacity, possibly compromising the balance over the years. However, Tai Chi Chuan is a martial art that can provide balance improvements in elderly people. This study aimed to evaluate balance in elderly after three and six months of Tai Chi Chuan practicing. Participants were 27 individuals (62±4.4 years) who underwent Tai Chi Chuan training (one hour each) twice a week, for six months. Balance was assessed by the Timed Up and Go (TUG) test, Berg Balance Scale (...

Effects of Growth Hormone and Insulin-Like Growth Factor-1 on Postoperative Muscle and Substrate Metabolism

Directory of Open Access Journals (Sweden)

Folke Hammarqvist

2010-01-01

To conclude, growth factors influences urea metabolism, protein degradation and protein synthesis. There was no clearcut additional effect when combining GH and IGF-1 but the study was probably underpowered to outrule this and effects on nitrogen balance.

Genetic parameters for energy balance, fat /protein ratio, body condition score and disease traits in German Holstein cows.

Science.gov (United States)

Buttchereit, N; Stamer, E; Junge, W; Thaller, G

2012-08-01

Various health problems in dairy cows have been related to the magnitude and duration of the energy deficit post partum. Energy balance indicator traits like fat/protein ratio in milk and body condition score could be used in selection programmes to help predicting breeding values for health traits, but currently there is a lack of appropriate genetic parameters. Therefore, genetic correlations among energy balance, fat/protein ratio, and body condition score, and mastitis, claw and leg diseases, and metabolic disorders were estimated using linear and threshold models on data from 1693 primiparous cows recorded within the first 180 days in milk. Average daily energy balance, milk fat/protein ratio and body condition score were 8 MJ NEL, 1.13 and 2.94, respectively. Disease frequencies (% cows with at least one case) were 24.6% for mastitis, 9.7% for metabolic disorders and 28.2% for claw and leg diseases. Heritability estimates were 0.06, 0.30 and 0.34 for energy balance, fat/protein ratio and body condition score, respectively. For the disease traits, heritabilities ranged between 0.04 and 0.15. The genetic correlations were, in general, associated with large standard errors, but, although not significant, the results suggest that an improvement of overall health can be expected if energy balance traits are included into future breeding programmes. A low fat/protein ratio might serve as an indicator for metabolic stability and health of claw and legs. Between body condition and mastitis, a significant negative correlation of -0.40 was estimated. The study provides a new insight into the role energy balance traits can play as auxiliary traits for robustness of dairy cows. It was concluded that both, fat/protein ratio and body condition score, are potential variables to describe how well cows can adapt to the challenge of early lactation. However, the genetic parameters should be re-estimated on a more comprehensive data set. © 2011 Blackwell Verlag GmbH.

Mind your step: metabolic energy cost while walking an enforced gait pattern.

Science.gov (United States)

Wezenberg, D; de Haan, A; van Bennekom, C A M; Houdijk, H

2011-04-01

The energy cost of walking could be attributed to energy related to the walking movement and energy related to balance control. In order to differentiate between both components we investigated the energy cost of walking an enforced step pattern, thereby perturbing balance while the walking movement is preserved. Nine healthy subjects walked three times at comfortable walking speed on an instrumented treadmill. The first trial consisted of unconstrained walking. In the next two trials, subject walked while following a step pattern projected on the treadmill. The steps projected were either composed of the averaged step characteristics (periodic trial), or were an exact copy including the variability of the steps taken while walking unconstrained (variable trial). Metabolic energy cost was assessed and center of pressure profiles were analyzed to determine task performance, and to gain insight into the balance control strategies applied. Results showed that the metabolic energy cost was significantly higher in both the periodic and variable trial (8% and 13%, respectively) compared to unconstrained walking. The variation in center of pressure trajectories during single limb support was higher when a gait pattern was enforced, indicating a more active ankle strategy. The increased metabolic energy cost could originate from increased preparatory muscle activation to ensure proper foot placement and a more active ankle strategy to control for lateral balance. These results entail that metabolic energy cost of walking can be influenced significantly by control strategies that do not necessary alter global gait characteristics. Copyright © 2011 Elsevier B.V. All rights reserved.

Urea and Ammonia Metabolism and the Control of Renal Nitrogen Excretion

Science.gov (United States)

Mitch, William E.; Sands, Jeff M.

2015-01-01

Renal nitrogen metabolism primarily involves urea and ammonia metabolism, and is essential to normal health. Urea is the largest circulating pool of nitrogen, excluding nitrogen in circulating proteins, and its production changes in parallel to the degradation of dietary and endogenous proteins. In addition to serving as a way to excrete nitrogen, urea transport, mediated through specific urea transport proteins, mediates a central role in the urine concentrating mechanism. Renal ammonia excretion, although often considered only in the context of acid-base homeostasis, accounts for approximately 10% of total renal nitrogen excretion under basal conditions, but can increase substantially in a variety of clinical conditions. Because renal ammonia metabolism requires intrarenal ammoniagenesis from glutamine, changes in factors regulating renal ammonia metabolism can have important effects on glutamine in addition to nitrogen balance. This review covers aspects of protein metabolism and the control of the two major molecules involved in renal nitrogen excretion: urea and ammonia. Both urea and ammonia transport can be altered by glucocorticoids and hypokalemia, two conditions that also affect protein metabolism. Clinical conditions associated with altered urine concentrating ability or water homeostasis can result in changes in urea excretion and urea transporters. Clinical conditions associated with altered ammonia excretion can have important effects on nitrogen balance. PMID:25078422

Metabolic dynamics in skeletal muscle during acute reduction in blood flow and oxygen supply to mitochondria: in-silico studies using a multi-scale, top-down integrated model.

Science.gov (United States)

Dash, Ranjan K; Li, Yanjun; Kim, Jaeyeon; Beard, Daniel A; Saidel, Gerald M; Cabrera, Marco E

2008-09-09

Control mechanisms of cellular metabolism and energetics in skeletal muscle that may become evident in response to physiological stresses such as reduction in blood flow and oxygen supply to mitochondria can be quantitatively understood using a multi-scale computational model. The analysis of dynamic responses from such a model can provide insights into mechanisms of metabolic regulation that may not be evident from experimental studies. For the purpose, a physiologically-based, multi-scale computational model of skeletal muscle cellular metabolism and energetics was developed to describe dynamic responses of key chemical species and reaction fluxes to muscle ischemia. The model, which incorporates key transport and metabolic processes and subcellular compartmentalization, is based on dynamic mass balances of 30 chemical species in both capillary blood and tissue cells (cytosol and mitochondria) domains. The reaction fluxes in cytosol and mitochondria are expressed in terms of a general phenomenological Michaelis-Menten equation involving the compartmentalized energy controller ratios ATP/ADP and NADH/NAD(+). The unknown transport and reaction parameters in the model are estimated simultaneously by minimizing the differences between available in vivo experimental data on muscle ischemia and corresponding model outputs in coupled with the resting linear flux balance constraints using a robust, nonlinear, constrained-based, reduced gradient optimization algorithm. With the optimal parameter values, the model is able to simulate dynamic responses to reduced blood flow and oxygen supply to mitochondria associated with muscle ischemia of several key metabolite concentrations and metabolic fluxes in the subcellular cytosolic and mitochondrial compartments, some that can be measured and others that can not be measured with the current experimental techniques. The model can be applied to test complex hypotheses involving dynamic regulation of cellular metabolism and

Alimentary, metabolic and toxic osteopathies in adults

Energy Technology Data Exchange (ETDEWEB)

Ellegast, H.H.

1986-12-01

Skeletal changes in deficient or badly balanced nutrition (alimentary osteopathies) and osseous changes accompanying chronic desease of internal organs and metabolic disorders (metabolic osteopathies) are discussed. Basically, the classical generalised skeletal changes such as osteoporosis, osteomalacia, fibroosteoclacia and sklerosis of the bone can occur in their pure form or as a combination of two or more of these disorders. Finally the exogenic toxic osteopathies are discussed, nowadays fluorosis being the most important. Other external factors may be drugs like methotrexate and antiepileptic medications.

Fasting metabolism modulates the interleukin-12/interleukin-10 cytokine axis.

Directory of Open Access Journals (Sweden)

Johannes J Kovarik

Full Text Available A crucial role of cell metabolism in immune cell differentiation and function has been recently established. Growing evidence indicates that metabolic processes impact both, innate and adaptive immunity. Since a down-stream integrator of metabolic alterations, mammalian target of rapamycin (mTOR, is responsible for controlling the balance between pro-inflammatory interleukin (IL-12 and anti-inflammatory IL-10, we investigated the effect of upstream interference using metabolic modulators on the production of pro- and anti-inflammatory cytokines. Cytokine release and protein expression in human and murine myeloid cells was assessed after toll-like receptor (TLR-activation and glucose-deprivation or co-treatment with 5'-adenosine monophosphate (AMP-activated protein kinase (AMPK activators. Additionally, the impact of metabolic interference was analysed in an in-vivo mouse model. Glucose-deprivation by 2-deoxy-D-glucose (2-DG increased the production of IL-12p40 and IL-23p19 in monocytes, but dose-dependently inhibited the release of anti-inflammatory IL-10. Similar effects have been observed using pharmacological AMPK activation. Consistently, an inhibition of the tuberous sclerosis complex-mTOR pathway was observed. In line with our in vitro observations, glycolysis inhibition with 2-DG showed significantly reduced bacterial burden in a Th2-prone Listeria monocytogenes mouse infection model. In conclusion, we showed that fasting metabolism modulates the IL-12/IL-10 cytokine balance, establishing novel targets for metabolism-based immune-modulation.

Fasting metabolism modulates the interleukin-12/interleukin-10 cytokine axis

Science.gov (United States)

Kernbauer, Elisabeth; Hölzl, Markus A.; Hofer, Johannes; Gualdoni, Guido A.; Schmetterer, Klaus G.; Miftari, Fitore; Sobanov, Yury; Meshcheryakova, Anastasia; Mechtcheriakova, Diana; Witzeneder, Nadine; Greiner, Georg; Ohradanova-Repic, Anna; Waidhofer-Söllner, Petra; Säemann, Marcus D.; Decker, Thomas

2017-01-01

A crucial role of cell metabolism in immune cell differentiation and function has been recently established. Growing evidence indicates that metabolic processes impact both, innate and adaptive immunity. Since a down-stream integrator of metabolic alterations, mammalian target of rapamycin (mTOR), is responsible for controlling the balance between pro-inflammatory interleukin (IL)-12 and anti-inflammatory IL-10, we investigated the effect of upstream interference using metabolic modulators on the production of pro- and anti-inflammatory cytokines. Cytokine release and protein expression in human and murine myeloid cells was assessed after toll-like receptor (TLR)-activation and glucose-deprivation or co-treatment with 5′-adenosine monophosphate (AMP)-activated protein kinase (AMPK) activators. Additionally, the impact of metabolic interference was analysed in an in-vivo mouse model. Glucose-deprivation by 2-deoxy-D-glucose (2-DG) increased the production of IL-12p40 and IL-23p19 in monocytes, but dose-dependently inhibited the release of anti-inflammatory IL-10. Similar effects have been observed using pharmacological AMPK activation. Consistently, an inhibition of the tuberous sclerosis complex-mTOR pathway was observed. In line with our in vitro observations, glycolysis inhibition with 2-DG showed significantly reduced bacterial burden in a Th2-prone Listeria monocytogenes mouse infection model. In conclusion, we showed that fasting metabolism modulates the IL-12/IL-10 cytokine balance, establishing novel targets for metabolism-based immune-modulation. PMID:28742108

An experimental study of the ion energy balance of a magnetized plasma

International Nuclear Information System (INIS)

Pots, B.F.M.; Hooff, P. van; Schram, D.C.; Sijde, B. van der

1981-01-01

A report is given on an experimental study of the ion energy balance of the magnetized and current-driven plasma f a hollow cathode discharge. The balance appears to be classical. At the axis of the plasma column the electron-ion Coulomb interaction is in equilibrium with the ion-neutral interaction. No significant influence on the energy balance by the spontaneously appearing plasma turbulence is formed. (author)

Using machine learning to assess covariate balance in matching studies.

Science.gov (United States)

Linden, Ariel; Yarnold, Paul R

2016-12-01

In order to assess the effectiveness of matching approaches in observational studies, investigators typically present summary statistics for each observed pre-intervention covariate, with the objective of showing that matching reduces the difference in means (or proportions) between groups to as close to zero as possible. In this paper, we introduce a new approach to distinguish between study groups based on their distributions of the covariates using a machine-learning algorithm called optimal discriminant analysis (ODA). Assessing covariate balance using ODA as compared with the conventional method has several key advantages: the ability to ascertain how individuals self-select based on optimal (maximum-accuracy) cut-points on the covariates; the application to any variable metric and number of groups; its insensitivity to skewed data or outliers; and the use of accuracy measures that can be widely applied to all analyses. Moreover, ODA accepts analytic weights, thereby extending the assessment of covariate balance to any study design where weights are used for covariate adjustment. By comparing the two approaches using empirical data, we are able to demonstrate that using measures of classification accuracy as balance diagnostics produces highly consistent results to those obtained via the conventional approach (in our matched-pairs example, ODA revealed a weak statistically significant relationship not detected by the conventional approach). Thus, investigators should consider ODA as a robust complement, or perhaps alternative, to the conventional approach for assessing covariate balance in matching studies. © 2016 John Wiley & Sons, Ltd.

Understanding the interrelationship between the synthesis of urea and gluconeogenesis by formulating an overall balanced equation.

Science.gov (United States)

Ipata, Piero L; Pesi, Rossana

2017-06-01

It is well known that a strong metabolic interrelationship exists between ureagenesis and gluconeogenesis. In this paper, we present a detailed, overall equation, describing a possible metabolic link between ureagenesis and gluconeogenesis. We adopted a guided approach in which we strongly suggest that students, when faced with the problem of obtaining the overall equation of a metabolic pathway, carefully account for all atoms and charges of the single reactions, as well as the cellular localizations of the substrates, and the related transport systems. If this suggestion is always taken into account, a balanced, overall equation of a metabolic pathway will be obtained, which strongly facilitates the discussion of its physiological role. Unfortunately, textbooks often report unbalanced overall equations of metabolic pathways, including ureagenesis and gluconeogenesis. Most likely the reason is that metabolism and enzymology have been neglected for about three decades, owing to the remarkable advances of molecular biology and molecular genetics. In this paper, we strongly suggest that students, when faced with the problem of obtaining the overall reaction of a metabolic pathway, carefully control if the single reactions are properly balanced for atoms and charges. Following this suggestion, we were able to obtain an overall equation describing the metabolic interrelationship between ureagenesis and gluconeogenesis, in which urea and glucose are the final products. The aim is to better rationalize this topic and to convince students and teachers that metabolism is an important and rewarding chapter of human physiology. Copyright © 2017 the American Physiological Society.

Nutritional and metabolic changes due the abdominal radiation: experimental study; Alteracoes nutricionais e do metabolismo energetico na irradiacao abdominal: estudo experimental

Energy Technology Data Exchange (ETDEWEB)

Mucerino, Donato R; Waitzberg, Dan L; Campos, Fabio G. de; Melo Auricchio, Maria T. de; Gama-Rodrigues, Joaquim J; Lima-Goncalves, Ernesto L [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Div. de Clinica Cirurgica II

1995-01-01

In this study the effects on nutritional status and energetic metabolism due the abdominal irradiation were analysed. Adult male wistar rats (48), were divided in two groups Control (C) and radiated (R). The rats were maintained all time in metabolic cages. the study was done in two periods: period 1 begun at 0 day, were rats adapted to cages and oral diet, had food and water ad libitum. At the day four indirect calorimetric measurements were performed (calorimetry 1). At period 2, group R rats abdominal radiation at a 300 c Gy/day rate, for 5 consecutive days, and group C started a pair-feeding process linked individually to R rats and suffered application to simulated-irradiation. Two other calorimetric measurements (II,III) were performing during period 2. After radiation the last calorimetry was performed (IV). At sacrifice (day 14) blood was collected for determination of hemoglobin, hematocrit, albumin and transferrin. There were no statistical differences among groups C and R during period 1 (p < 0.05). Great reduction in food intake and weight variation were found in period 2, but weight loss was significantly higher in R rats. Nitrogen balance decrease in period 2, but without difference among the groups (p < 0.05). Serum albumin was significantly lower in R rats. Respiratory quotient decreased in both groups during period 2, but rats kept it lower (p < 0.05). The energy expenditure level decreased after radiation in group R. During period 2 total substrate oxidation decreased in R rats. Radiation decrease glucose and protein oxidation. In conclusion, in this study`s conditions, radiation produced malnutrition by reducing food intake by bringing weight loss, hypoalbuminemia and decrease nitrogen balance. Radiation was also responsible for a reduction of metabolism, by promoting the fall of energy expenditure. These changes are not only due the anorexia, undoubtful a main factor. (author). 60 refs., 3 figs., 4 tabs.

Current imaging methods for evaluation of metabolic risk in pediatric patients

International Nuclear Information System (INIS)

Balev, B.; Lateva, M.; Popova, R.; Teneva, Ts.; Iotova, V.

2013-01-01

Full text: Introduction: The incidence of cardio - metabolic diseases increase in an increasingly early age is one of the challenges of the 21st century. This phenomenon is attributed largely of the obesity epidemic, it is particularly significant when the obesity occurs in childhood - obese children have a greater probability of developing cardiovascular disease and diabetes earlier. What you will learn: The significance of the obesity epidemic in childhood and metabolic risk increase; The compartment of adipose tissue and their role in maintaining metabolic balance and its breach; The importance of imaging methods in recent studies related to obesity and cardio - metabolic diseases in children; New imaging methods for proofing of pathological fat accumulation in other tissues and organs and their role in the study of metabolic disorders. Discussion: Various studies of pathology at obesity prove that obesity indicators are not sufficient for individualized assessment of cardio - metabolic risk. Only by imaging methods, information about the accumulated fat in metabolically more active visceral and ectopic adipose tissue depots has been obtained. The most common imaging techniques for analysis of body composition and adiposity in children - dual-energy X-ray absorptiometry (DXA), ultrasound , computed tomography ( CT) scan , magnetic resonance imaging ( MRI), magnetic resonance spectroscopy (MRS) will be presented. Conclusion: The imaging methods are widely used in the obesity and metabolic risk studies, as the trend is to be applied increasingly into practice. The results from Imaging studies affect not only to therapeutic approach, but also to the motivation of parents and patients to comply prescribed measures

Balancing dual roles in self-employed women: An exploratory study

Directory of Open Access Journals (Sweden)

Kirsty-Lee McLellan

2009-04-01

Full Text Available This study is aimed at exploring how self-employed women cope in balancing their dual roles as mothers and executives. Through the elicitation of constructs by making use of Kelly’s repertory grid technique, the personal construct system of five self-employed white women in Gauteng across varying industries was established. While being successful dual earners, they still bore the primary responsibility for nurturing their families and assuring their well-being. The successful balancing of their dual roles was attributed to the following central themes, which emerged from all the participants: quality time spent with children and family, structure and planning, coping with guilt, support structures and self-reliance, and balance between work and life.

Metabolic mystery: Aging, obesity, diabetes and ventromedial hypothalamus

OpenAIRE

Mobbs, Charles V.; Moreno, Cesar L.; Poplawski, Michael

2013-01-01

We propose that energy balance, glucose homeostasis, and aging are all regulated largely by the same nutrient-sensing neurons in the ventromedial hypothalamus (VMH)., Although the central role of these neurons in regulating energy balance is clear, their role in regulating glucose homeostasis has only become more clear recently. It is the latter function that may be most relevant to aging and lifespan, by controlling the rate of glucose metabolism. Specifically, glucose-sensing neurons in VMH...

Expanded flux variability analysis on metabolic network of Escherichia coli

Institute of Scientific and Technical Information of China (English)

CHEN Tong; XIE ZhengWei; OUYANG Qi

2009-01-01

Flux balance analysis,based on the mass conservation law in a cellular organism,has been extensively employed to study the interplay between structures and functions of cellular metabolic networks.Consequently,the phenotypes of the metabolism can be well elucidated.In this paper,we introduce the Expanded Flux Variability Analysis (EFVA) to characterize the intrinsic nature of metabolic reactions,such as flexibility,modularity and essentiality,by exploring the trend of the range,the maximum and the minimum flux of reactions.We took the metabolic network of Escherichia coli as an example and analyzed the variability of reaction fluxes under different growth rate constraints.The average variability of all reactions decreases dramatically when the growth rate increases.Consider the noise effect on the metabolic system,we thus argue that the microorganism may practically grow under a suboptimal state.Besides,under the EFVA framework,the reactions are easily to be grouped into catabolic and anabolic groups.And the anabolic groups can be further assigned to specific biomass constitute.We also discovered the growth rate dependent essentiality of reactions.

Metabolic cost of incubation in the Laysan albatross and Bonin petrel.

Science.gov (United States)

Grant, G S; Whittow, G C

1983-01-01

1. Oxygen consumption and carbon dioxide production were measured in resting and incubating Laysan albatrosses and Bonin petrels on Midway Atoll in the north central Pacific Ocean. 2. Incubation metabolism within the thermal neutral zone is less than or equal to resting metabolism in the albatross and petrel. 3. The respiratory quotients (0.64-0.72) during the long fasts indicate fat metabolism. 4. The estimated fractional water content of the albatross and petrel do not change during incubation fasts because water loss is balanced by metabolic water production.

A Study on Work Life Balance of Female Teachers in Ernakulam District

OpenAIRE

Sabnam EA; Neena Merina; Dr Vineeth KM

2018-01-01

Work-life balance is about creating and maintaining supportive and healthy work environments, which will enable employees to have a balance between work and personal responsibilities and thus strengthening employee loyalty and productivity. Evidence suggests that improvements in people management practices, especially work time and work location flexibility and the development of supportive managers, contribute to increased work-life balance. The present study concludes that Work Place Suppor...

Typical balance exercises or exergames for balance improvement?

Science.gov (United States)

Gioftsidou, Asimenia; Vernadakis, Nikolaos; Malliou, Paraskevi; Batzios, Stavros; Sofokleous, Polina; Antoniou, Panagiotis; Kouli, Olga; Tsapralis, Kyriakos; Godolias, George

2013-01-01

Balance training is an effective intervention to improve static postural sway and balance. The purpose of the present study was to investigate the effectiveness of the Nintendo Wii Fit Plus exercises for improving balance ability in healthy collegiate students in comparison with a typical balance training program. Forty students were randomly divided into two groups, a traditional (T group) and a Nintendo Wii group (W group) performed an 8 week balance program. The "W group" used the interactive games as a training method, while the "T group" used an exercise program with mini trampoline and inflatable discs (BOSU). Pre and Post-training participants completed balance assessments. Two-way repeated measures analyses of variance (ANOVAs) were conducted to determine the effect of training program. Analysis of the data illustrated that both training program groups demonstrated an improvement in Total, Anterior-posterior and Medial Lateral Stability Index scores for both limbs. Only at the test performed in the balance board with anterior-posterior motion, the improvement in balance ability was greater in the "T group" than the "W group", when the assessment was performed post-training (p=0.023). Findings support the effectiveness of using the Nintendo Wii gaming console as a balance training intervention tool.

A qualitative study of work-life balance amongst specialist orthodontists in the United Kingdom.

Science.gov (United States)

Bateman, Lindsey E; Collins, Joanne M; Cunningham, Susan J

2016-12-01

To identify factors affecting work-life balance amongst male and female orthodontists in the UK. A qualitative interview-based study with a cross-sectional design. Specialist orthodontists working in specialist practice and the hospital service in the UK were selected by purposive sampling. In-depth semi-structured interviews were conducted with 18 orthodontic specialists. Interview transcripts were analyzed using Framework Analysis. Four main themes pertaining to work-life balance in orthodontics were identified: work factors affecting work-life balance, life factors affecting work-life balance, perception and effects of work-life balance and suggestions for managing work-life balance within the profession. There was substantial variation in the work-life balance of the orthodontists interviewed in this study; however the majority reported high levels of career satisfaction despite difficulties maintaining a good work-life balance. Whilst there were some clear distinctions in the factors affecting work-life balance between the hospital environment and specialist practice (including additional professional commitments and teaching/training-related issues), there were also a number of similarities. These included, the lack of flexibility in the working day, managing patient expectations, taking time off work at short notice and the ability to work part-time.

Do budget balance rules anchor budget balance expectations? -- Some international evidence

OpenAIRE

Rülke, Jan-Christoph; Frenkel, Michael; Lis, Eliza

2013-01-01

This is the first study that analyzes whether budget balance expectations are anchored and whether budget balance rules effectively anchor expectations. To this end, we use a unique data set which covers budget balance expectations in 17 countries that implemented a budget balance rules. While our results are mixed concerning the general impact of budget balance rules on anchoring expectations, we do find that specific features of budget balance rules are important to successfully anchor budg...

Alimentary, metabolic and toxic osteopathies in adults

International Nuclear Information System (INIS)

Ellegast, H.H.

1986-01-01

Skeletal changes in deficient or badly balanced nutrition (alimentary osteopathies) and osseous changes accompanying chronic desease of internal organs and metabolic disorders (metabolic osteopathies) are discussed. Basically, the classical generalised skeletal changes such as osteoporosis, osteomalacia, fibroosteoclacia and sklerosis of the bone can occur in their pure form or as a combination of two or more of these disorders. Finally the exogenic toxic osteopathies are discussed, nowadays fluorosis being the most important. Other external factors may be drugs like methotrexate and antiepileptic medications. (orig.) [de

Relationship between metabolism and ovarian activity in dairy cows with different dry period lengths

NARCIS (Netherlands)

Chen, J.C.; Soede, N.M.; Dorland, van H.A.; Remmelink, G.J.; Bruckmaier, R.M.; Kemp, B.; Knegsel, van A.T.M.

2015-01-01

The objectives of the present study were to evaluate the effects of dry period length on ovarian activity in cows fed a lipogenic or a glucogenic diet within 100 days in milk (DIM) and to determine relationships between ovarian activity and energy balance and metabolic status in early lactation.

Regulation of brown adipocyte metabolism by myostatin/follistatin signaling

Directory of Open Access Journals (Sweden)

Rajan eSingh

2014-10-01

Full Text Available Obesity develops from perturbations of cellular bioenergetics, when energy uptake exceeds energy expenditure, and represents a major risk factor for the development of type 2 diabetes, dyslipidemia, cardiovascular disease, cancer, and other conditions. Brown adipose tissue (BAT has long been known to dissipate energy as heat and contribute to energy expenditure, but its presence and physiological role in adult human physiology has been questioned for years. Recent demonstrations of metabolically active brown fat depots in adult humans have revolutionized current therapeutic approaches for obesity-related diseases. The balance between white adipose tissue (WAT and BAT affects the systemic energy balance and is widely believed to be the key determinant in the development of obesity and related metabolic diseases. Members of the transforming growth factor-beta (TGF-β superfamily play an important role in regulating overall energy homeostasis by modulation of brown adipocyte characteristics. Inactivation of TGF-β/Smad3/myostatin (Mst signaling promotes browning of white adipocytes, increases mitochondrial biogenesis and protects mice from diet-induced obesity, suggesting the need for development of a novel class of TGF-β/Mst antagonists for the treatment of obesity and related metabolic diseases. We recently described an important role of follistatin (Fst, a soluble glycoprotein that is known to bind and antagonize Mst actions, during brown fat differentiation and the regulation of cellular metabolism. Here we highlight various investigations performed using different in vitro and in vivo models to support the contention that targeting TGF-β/Mst signaling enhances brown adipocyte functions and regulates energy balance, reducing insulin resistance and curbing the development of obesity and diabetes.

Essential role of UCP1 modulating the central effects of thyroid hormones on energy balance

Science.gov (United States)

Alvarez-Crespo, Mayte; Csikasz, Robert I.; Martínez-Sánchez, Noelia; Diéguez, Carlos; Cannon, Barbara; Nedergaard, Jan; López, Miguel

2016-01-01

Objective Classically, metabolic effects of thyroid hormones (THs) have been considered to be peripherally mediated, i.e. different tissues in the body respond directly to thyroid hormones with an increased metabolism. An alternative view is that the metabolic effects are centrally regulated. We have examined here the degree to which prolonged, centrally infused triiodothyronine (T3) could in itself induce total body metabolic effects and the degree to which brown adipose tissue (BAT) thermogenesis was essential for such effects, by examining uncoupling protein 1 (UCP1) KO mice. Methods Wildtype and UPC1 KO mice were centrally-treated with T3 by using minipumps. Metabolic measurements were analyzed by indirect calorimetry and expression analysis by RT-PCR or western blot. BAT morphology and histology were studied by immunohistochemistry. Results We found that central T3-treatment led to reduced levels of hypothalamic AMP-activated protein kinase (AMPK) and elevated body temperature (0.7 °C). UCP1 was essential for the T3-induced increased rate of energy expenditure, which was only observable at thermoneutrality and notably only during the active phase, for the increased body weight loss, for the increased hypothalamic levels of neuropeptide Y (NPY) and agouti-related peptide (AgRP) and for the increased food intake induced by central T3-treatment. Prolonged central T3-treatment also led to recruitment of BAT and britening/beiging (“browning”) of inguinal white adipose tissue (iWAT). Conclusions We conclude that UCP1 is essential for mediation of the central effects of thyroid hormones on energy balance, and we suggest that similar UCP1-dependent effects may underlie central energy balance effects of other agents. PMID:27069867

Two-Scale 13C Metabolic Flux Analysis for Metabolic Engineering.

Science.gov (United States)

Ando, David; Garcia Martin, Hector

2018-01-01

Accelerating the Design-Build-Test-Learn (DBTL) cycle in synthetic biology is critical to achieving rapid and facile bioengineering of organisms for the production of, e.g., biofuels and other chemicals. The Learn phase involves using data obtained from the Test phase to inform the next Design phase. As part of the Learn phase, mathematical models of metabolic fluxes give a mechanistic level of comprehension to cellular metabolism, isolating the principle drivers of metabolic behavior from the peripheral ones, and directing future experimental designs and engineering methodologies. Furthermore, the measurement of intracellular metabolic fluxes is specifically noteworthy as providing a rapid and easy-to-understand picture of how carbon and energy flow throughout the cell. Here, we present a detailed guide to performing metabolic flux analysis in the Learn phase of the DBTL cycle, where we show how one can take the isotope labeling data from a 13 C labeling experiment and immediately turn it into a determination of cellular fluxes that points in the direction of genetic engineering strategies that will advance the metabolic engineering process.For our modeling purposes we use the Joint BioEnergy Institute (JBEI) Quantitative Metabolic Modeling (jQMM) library, which provides an open-source, python-based framework for modeling internal metabolic fluxes and making actionable predictions on how to modify cellular metabolism for specific bioengineering goals. It presents a complete toolbox for performing different types of flux analysis such as Flux Balance Analysis, 13 C Metabolic Flux Analysis, and it introduces the capability to use 13 C labeling experimental data to constrain comprehensive genome-scale models through a technique called two-scale 13 C Metabolic Flux Analysis (2S- 13 C MFA) [1]. In addition to several other capabilities, the jQMM is also able to predict the effects of knockouts using the MoMA and ROOM methodologies. The use of the jQMM library is

In vitro metabolism and permeation studies in rat jejunum

DEFF Research Database (Denmark)

Gammelgaard, Bente; Jensen, K; Steffansen, B

1999-01-01

The purpose of these studies was to compare the in vitro absorption of two inorganic chromium(III) compounds: chromium chloride and chromium nitrate, with organic chromium(III)-picolinate; and to investigate if any in vitro metabolism of chromium(VI) takes place. The in vitro metabolism studies...

Effects of the antituberculous drug ethambutol on zinc balance, distribution, and turnover: short-term studies modeling chronic toxicity

International Nuclear Information System (INIS)

King, A.B.

1987-01-01

Alterations in Zn metabolism have been reported in both tuberculous patients and experimental animals receiving ethambutol (d-2-2'-ethylenediimino-di-1-butanol dihydrochloride) (EMB), and these changes have been associated with ocular side effects of EMB. EMB has chelating properties but is not likely to chelate Zn at physiologic pH. However, its acid metabolite is a stronger chelator. This research addressed whether EMB affects the absorption and disposition of dietary Zn, and whether effects of EMB on Zn are modified by (a) marginal Zn intake of (b) drugs that may induce metabolism of EMB. Weanling male Sprague-Dawley rats fed an AIN-76A diet received daily by gavage either deionized water or EMB doses of 400-1600 mg/kg bw. in a preliminary, 15-day dose-response study and 400-600 mg/kg in three subsequent 15- to 30-day studies. Apparent absorption and biological turnover of Zn were measured by 65 Zn balance and retention in rats fed adequate (49 ppm) or marginal (11 ppm) Zn. Effects of EMB were similar in both dietary groups. EMB treatment produced alopecia and reduced feed intake, feed efficiency, weight gain, and serum Zn, but showed no effect on hepatic, renal, or femoral Zn concentrations. Absorption, turnover, and urinary excretion of Zn were increased in rats fed EMB

Effects of the antituberculous drug ethambutol on zinc balance, distribution, and turnover: short-term studies modeling chronic toxicity

Energy Technology Data Exchange (ETDEWEB)

King, A.B.

1987-01-01

Alterations in Zn metabolism have been reported in both tuberculous patients and experimental animals receiving ethambutol (d-2-2'-ethylenediimino-di-1-butanol dihydrochloride) (EMB), and these changes have been associated with ocular side effects of EMB. EMB has chelating properties but is not likely to chelate Zn at physiologic pH. However, its acid metabolite is a stronger chelator. This research addressed whether EMB affects the absorption and disposition of dietary Zn, and whether effects of EMB on Zn are modified by (a) marginal Zn intake of (b) drugs that may induce metabolism of EMB. Weanling male Sprague-Dawley rats fed an AIN-76A diet received daily by gavage either deionized water or EMB doses of 400-1600 mg/kg bw. in a preliminary, 15-day dose-response study and 400-600 mg/kg in three subsequent 15- to 30-day studies. Apparent absorption and biological turnover of Zn were measured by /sup 65/Zn balance and retention in rats fed adequate (49 ppm) or marginal (11 ppm) Zn. Effects of EMB were similar in both dietary groups. EMB treatment produced alopecia and reduced feed intake, feed efficiency, weight gain, and serum Zn, but showed no effect on hepatic, renal, or femoral Zn concentrations. Absorption, turnover, and urinary excretion of Zn were increased in rats fed EMB.

Effect of a balance-training programme on postural balance, aerobic capacity and frequency of falls in women with osteoporosis: A randomized controlled trial

Directory of Open Access Journals (Sweden)

Ibolya Miko

2018-05-01

Full Text Available Objective: To investigate the effect of a 12-month complex balance-training programme on static and dynamic postural balance, aerobic capacity and frequency of falls in women with established osteoporosis. Design: Randomized controlled trial in which the intervention group was assigned a 12-month exercise programme (3 times a week for 30 min and the control group had no intervention. Subjects: A total of 100 osteoporotic women with at least one previous fracture. Methods: Performance-based Timed Up and Go (TUG, Berg Balance Scale (BBS and stabilometric platform tests were used to evaluate balance. Aerobic capacity was measured by bicycle ergometry. Frequency of falls was assessed using a falls diary. Results: After 1 year, there was a statistically significant difference between the improvement achieved in the intervention and control groups on the performance-based TUG, BBS and stabilometric platform tests (p < 0.05. Mean metabolic equivalent (MET value decreased in the intervention group, from 4.91 to 3.82 (a significant difference from the change achieved in the control group; p = 0.05. Relative risk of falls was 0.534 at 1 year (p = 0.17. Conclusion: The 12-month balance-training programme significantly improved postural balance and increased aerobic capacity in women with established osteoporosis.

Role of Hypothalamic VGF in Energy Balance and Metabolic Adaption to Environmental Enrichment in Mice

Science.gov (United States)

Foglesong, Grant D.; Huang, Wei; Liu, Xianglan; Slater, Andrew M.; Siu, Jason; Yildiz, Vedat; Salton, Stephen R. J.

2016-01-01

Environmental enrichment (EE), a housing condition providing complex physical, social, and cognitive stimulation, leads to improved metabolic health and resistance to diet-induced obesity and cancer. One underlying mechanism is the activation of the hypothalamic-sympathoneural-adipocyte axis with hypothalamic brain-derived neurotrophic factor (BDNF) as the key mediator. VGF, a peptide precursor particularly abundant in the hypothalamus, was up-regulated by EE. Overexpressing BDNF or acute injection of BDNF protein to the hypothalamus up-regulated VGF, whereas suppressing BDNF signaling down-regulated VGF expression. Moreover, hypothalamic VGF expression was regulated by leptin, melanocortin receptor agonist, and food deprivation mostly paralleled to BDNF expression. Recombinant adeno-associated virus-mediated gene transfer of Cre recombinase to floxed VGF mice specifically decreased VGF expression in the hypothalamus. In contrast to the lean and hypermetabolic phenotype of homozygous germline VGF knockout mice, specific knockdown of hypothalamic VGF in male adult mice led to increased adiposity, decreased core body temperature, reduced energy expenditure, and impaired glucose tolerance, as well as disturbance of molecular features of brown and white adipose tissues without effects on food intake. However, VGF knockdown failed to block the EE-induced BDNF up-regulation or decrease of adiposity indicating a minor role of VGF in the hypothalamic-sympathoneural-adipocyte axis. Taken together, our results suggest hypothalamic VGF responds to environmental demands and plays an important role in energy balance and glycemic control likely acting in the melanocortin pathway downstream of BDNF. PMID:26730934

Biomechanical assessment of dynamic balance: Specificity of different balance tests.

Science.gov (United States)

Ringhof, Steffen; Stein, Thorsten

2018-04-01

Dynamic balance is vitally important for most sports and activities of daily living, so the assessment of dynamic stability has become an important issue. In consequence, a large number of balance tests have been developed. However, it is not yet known whether these tests (i) measure the same construct and (ii) can differentiate between athletes with different balance expertise. We therefore studied three common dynamic balance tests: one-leg jump landings, Posturomed perturbations and simulated forward falls. Participants were 24 healthy young females in regular training in either gymnastics (n = 12) or swimming (n = 12). In each of the tests, the participants were instructed to recover balance as quickly as possible. Dynamic stability was computed by time to stabilization and margin of stability, deduced from force plates and motion capture respectively. Pearson's correlations between the dynamic balance tests found no significant associations between the respective dynamic stability measures. Furthermore, independent t-tests indicated that only jump landings could properly distinguish between both groups of athletes. In essence, the different dynamic balance tests applied did not measure the same construct but rather task-specific skills, each of which depends on multifactorial internal and external constraints. Our study therefore contradicts the traditional view of considering balance as a general ability, and reinforces that dynamic balance measures are not interchangeable. This highlights the importance of selecting appropriate balance tests. Copyright © 2018 Elsevier B.V. All rights reserved.

Neuronal control of energy balance and modulation of muscle aging by the transcriptional coactivator PGC-1α

OpenAIRE

Gill, Jonathan François

2016-01-01

Cellular metabolic adaptations play a central role in the body's response to environmental changes and external stimuli and allow the maintenance of a proper energy balance. Transcriptional activators enable the integration of incoming signals and sensing of altered energy levels. Dysregulation of such metabolic pathways is a common mechanism of various tissue dysfunctions contributing to different diseases. A key player in cellular metabolism is the transcriptional coregulator Peroxisome pro...

Body composition changes and cardiometabolic benefits of a balanced Italian Mediterranean Diet in obese patients with metabolic syndrome.

Science.gov (United States)

Di Daniele, Nicola; Petramala, Luigi; Di Renzo, Laura; Sarlo, Francesca; Della Rocca, Domenico Giovanni; Rizzo, Mariagiovanna; Fondacaro, Valentina; Iacopino, Leonardo; Pepine, Carl J; De Lorenzo, Antonino

2013-06-01

Metabolic syndrome (MS) is a cluster of metabolic alteration associated with a higher risk of cardiovascular disease and overall mortality than the single alterations alone. The Italian Mediterranean Diet (IMD) can exert a positive effect on cardiovascular risk and related morbidity and mortality. The aim was to evaluate the benefits of dietary intervention based on a typical IMD on body composition, cardiometabolic changes and reduction in cardiovascular disease in patients with MS. Eighty White Italian subjects with MS were prescribed a balanced hypocaloric IMD. We investigated dietary habits and impact of the diet on health status, blood biochemical markers, anthropometric measurements and body composition during a 6-month follow-up period. Body composition, fat mass and distribution were assessed by Dual X-ray absorptiometry. Adherence to the IMD led to a decrease in body weight (102.59 ± 16.82 to 92.39 ± 15.94 kg, p < 0.001), body mass index (BMI) (38.57 ± 6.94 to 35.10 ± 6.76, <0.001) and waist circumference (112.23 ± 12.55 vs 92.42 ± 18.17 cm, p < 0.001). A significant loss of total body fat especially in waist region was observed. The MS was resolved in 52 % of the patients. Significant improvements in systolic and diastolic blood pressure and fasting glucose occurred. Low-density lipoprotein cholesterol was reduced from 128.74 ± 33.18 to 108.76 ± 38.61 mg/dl (p < 0.001), triglycerides from 169.81 ± 80.80 to 131.02 ± 63.88 mg/dl (p < 0.001). The present results suggest that a dietary intervention based on a typical IMD effectively promotes weight loss and reduces the growing burden of cardiovascular risk factors that typifies patients with MS.

Metabolic adaption of ethanol-tolerant Clostridium thermocellum.

Directory of Open Access Journals (Sweden)

Xinshu Zhu

Full Text Available Clostridium thermocellum is a major candidate for bioethanol production via consolidated bioprocessing. However, the low ethanol tolerance of the organism dramatically impedes its usage in industry. To explore the mechanism of ethanol tolerance in this microorganism, systematic metabolomics was adopted to analyse the metabolic phenotypes of a C. thermocellum wild-type (WT strain and an ethanol-tolerant strain cultivated without (ET0 or with (ET3 3% (v/v exogenous ethanol. Metabolomics analysis elucidated that the levels of numerous metabolites in different pathways were changed for the metabolic adaption of ethanol-tolerant C. thermocellum. The most interesting phenomenon was that cellodextrin was significantly more accumulated in the ethanol-tolerant strain compared with the WT strain, although cellobiose was completely consumed in both the ethanol-tolerant and wild-type strains. These results suggest that the cellodextrin synthesis was active, which might be a potential mechanism for stress resistance. Moreover, the overflow of many intermediate metabolites, which indicates the metabolic imbalance, in the ET0 cultivation was more significant than in the WT and ET3 cultivations. This indicates that the metabolic balance of the ethanol-tolerant strain was adapted better to the condition of ethanol stress. This study provides additional insight into the mechanism of ethanol tolerance and is valuable for further metabolic engineering aimed at higher bioethanol production.

The Balance Control of Children with and without Hearing Impairment in Singapore--A Case Study

Science.gov (United States)

Jernice, Tan Sing Yee; Nonis, Karen P.; Yi, Chow Jia

2011-01-01

The purpose of this study is to compare the balance control of participants with and without HI and also to investigate the effect of a Balance Programme (BP) on their balance control (HI; n = 2, M age = 7 years old). The BP consisted of six practice sessions of 45 minutes each. The Balance Tasks used to assess balance control were static Balance…

Metabolic and improved organ scan studies. III. 13N-ammonia metabolic studies in hepatic encephalopathy

International Nuclear Information System (INIS)

Anon.

1976-01-01

Results are reported from an investigation into the nature of hepatic encephalopathy, through study of the uptake and metabolism of 13 N-labeled ammonia by the brain in relation to liver function, in order to develop improved methods for the management of patients with this condition

Elucidating the adaptation and temporal coordination of metabolic pathways using in-silico evolution

Czech Academy of Sciences Publication Activity Database

Gottstein, W.; Müller, Stefan; Herzel, H.; Steuer, Ralf

2014-01-01

Roč. 117, mar (2014), s. 68-76 ISSN 0303-2647 R&D Projects: GA MŠk(CZ) EE2.3.20.0256 Institutional support: RVO:67179843 Keywords : evolutionary algorithms * flux- balance analysis * metabolic oscillations * metabolism * systems biology Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.548, year: 2014

A balanced ATP driving force module for enhancing photosynthetic biosynthesis of 3-hydroxybutyrate from CO2.

Science.gov (United States)

Ku, Jason T; Lan, Ethan I

2018-03-01

Using engineered photoautotrophic microorganisms for the direct chemical synthesis from CO 2 is an attractive direction for both sustainability and CO 2 mitigation. However, the behaviors of non-native metabolic pathways may be difficult to control due to the different intracellular contexts between natural and heterologous hosts. While most metabolic engineering efforts focus on strengthening driving forces in pathway design to favor biochemical production in these organisms, excessive driving force may be detrimental to product biosynthesis due to imbalanced cellular intermediate distribution. In this study, an ATP-hydrolysis based driving force module was engineered into cyanobacterium Synechococcus elongatus PCC 7942 to produce 3-hydroxybutyrate (3HB), a valuable chemical feedstock for the synthesis of biodegradable plastics and antibiotics. However, while the ATP driving force module is effective for increasing product formation, uncontrolled accumulation of intermediate metabolites likely led to metabolic imbalance and thus to cell growth inhibition. Therefore, the ATP driving force module was reengineered by providing a reversible outlet for excessive carbon flux. Upon expression of this balanced ATP driving force module with 3HB biosynthesis, engineered strain produced 3HB with a cumulative titer of 1.2 g/L, a significant increase over the initial strain. This result highlighted the importance of pathway reversibility as an effective design strategy for balancing driving force and intermediate accumulation, thereby achieving a self-regulated control for increased net flux towards product biosynthesis. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Flipping the Metabolic Switch: Understanding and Applying Health Benefits of Fasting

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Anton, Stephen D.; Moehl, Keelin; Donahoo, William T.; Marosi, Krisztina; Lee, Stephanie; Mainous, Arch G.; Leeuwenburgh, Christiaan; Mattson, Mark P.

2017-01-01

Intermittent fasting (IF) is a term used to describe a variety of eating patterns in which no or few calories are consumed for time periods that can range from 12 hours to several days, on a recurring basis. Here we focus on the physiological responses of major organ systems, including the musculoskeletal system, to the onset of the metabolic switch – the point of negative energy balance at which liver glycogen stores are depleted and fatty acids are mobilized (typically beyond 12 hours after cessation of food intake). Emerging findings suggest the metabolic switch from glucose to fatty acid-derived ketones represents an evolutionarily conserved trigger point that shifts metabolism from lipid/cholesterol synthesis and fat storage to mobilization of fat through fatty acid oxidation and fatty-acid derived ketones, which serve to preserve muscle mass and function. Thus, IF regimens that induce the metabolic switch have the potential to improve body composition in overweight individuals. Moreover, IF regimens also induce the coordinated activation of signaling pathways that optimize physiological function, enhance performance, and slow aging and disease processes. Future randomized controlled IF trials should use biomarkers of the metabolic switch (e.g., plasma ketone levels) as a measure of compliance and the magnitude of negative energy balance during the fasting period. PMID:29086496

DIAGNOSIS OF FINANCIAL POSITION BY BALANCE SHEET ANALYSIS - CASE STUDY

OpenAIRE

Hada Teodor; Marginean Radu

2013-01-01

This study aims to elucidate and to exemplify an important technique for assessing the economic entities, namely the fundamental analysis of the balance sheet, in several significant aspects. The analysis of financial data reported in the balance sheet are, for an economic entity, the basis of a principle diagnosis by determining specific indicators of economic and financial analysis. This analysis aims to provide an insight into the companyâ€(tm)s financial position. The stated aim of this s...

Peroxisome Proliferators-Activated Receptor (PPAR Modulators and Metabolic Disorders

Directory of Open Access Journals (Sweden)

Min-Chul Cho

2008-01-01

Full Text Available Overweight and obesity lead to an increased risk for metabolic disorders such as impaired glucose regulation/insulin resistance, dyslipidemia, and hypertension. Several molecular drug targets with potential to prevent or treat metabolic disorders have been revealed. Interestingly, the activation of peroxisome proliferator-activated receptor (PPAR, which belongs to the nuclear receptor superfamily, has many beneficial clinical effects. PPAR directly modulates gene expression by binding to a specific ligand. All PPAR subtypes (α,γ, and σ are involved in glucose metabolism, lipid metabolism, and energy balance. PPAR agonists play an important role in therapeutic aspects of metabolic disorders. However, undesired effects of the existing PPAR agonists have been reported. A great deal of recent research has focused on the discovery of new PPAR modulators with more beneficial effects and more safety without producing undesired side effects. Herein, we briefly review the roles of PPAR in metabolic disorders, the effects of PPAR modulators in metabolic disorders, and the technologies with which to discover new PPAR modulators.

Genetic and environmental relationships of metabolic and weight phenotypes to metabolic syndrome and diabetes: the healthy twin study.

Science.gov (United States)

Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

2015-02-01

We aimed to examine the relationships, including genetic and environmental correlations, between metabolic and weight phenotypes and factors related to diabetes and metabolic syndrome. Participants of the Healthy Twin Study without diabetes (n=2687; 895 monozygotic and 204 dizygotic twins, and 1588 nontwin family members; mean age, 42.5±13.1 years) were stratified according to body mass index (BMI) (metabolic syndrome categories at baseline. The metabolic traits, namely diabetes and metabolic syndrome, metabolic syndrome components, glycated hemoglobin (HbA1c) level, and homeostasis model assessment of insulin resistance (HOMA-IR), were assessed after 2.5±2.1 years. In a multivariate-adjusted model, those who had metabolic syndrome or overweight phenotypes at baseline were more likely to have higher HbA1C and HOMA-IR levels and abnormal metabolic syndrome components at follow-up as compared to the metabolically healthy normal weight subgroup. The incidence of diabetes was 4.4-fold higher in the metabolically unhealthy but normal weight individuals and 3.3-fold higher in the metabolically unhealthy and overweight individuals as compared with the metabolically healthy normal weight individuals. The heritability of the metabolic syndrome/weight phenotypes was 0.40±0.03. Significant genetic and environmental correlations were observed between the metabolic syndrome/weight phenotypes at baseline and the metabolic traits at follow-up, except for incident diabetes, which only had a significant common genetic sharing with the baseline phenotypes. The genetic and environmental relationships between the metabolic and weight phenotypes at baseline and the metabolic traits at follow-up suggest pleiotropic genetic mechanisms and the crucial role of lifestyle and behavioral factors.

Balancing Audio

DEFF Research Database (Denmark)

Walther-Hansen, Mads

2016-01-01

is not thoroughly understood. In this paper I treat balance as a metaphor that we use to reason about several different actions in music production, such as adjusting levels, editing the frequency spectrum or the spatiality of the recording. This study is based on an exploration of a linguistic corpus of sound......This paper explores the concept of balance in music production and examines the role of conceptual metaphors in reasoning about audio editing. Balance may be the most central concept in record production, however, the way we cognitively understand and respond meaningfully to a mix requiring balance...

BASIC Training: A Pilot Study of Balance/Strengthening Exercises in Heart Failure.

Science.gov (United States)

McGuire, Rita; Honaker, Julie; Pozehl, Bunny; Hertzog, Melody

2018-05-19

The aim of this pilot study was to evaluate the effect of a multicomponent balance and resistance training intervention on physical function, balance, and falls in older (≥65 years) community-dwelling heart failure (HF) patients. Randomized, two-group repeated-measures experimental design. The intervention involved once weekly supervised group sessions with home sessions encouraged twice weekly. Focus groups held pre/post intervention. Outcome variables included measures of physical function, balance confidence, and falling risk. In a sample size of 33, the Dynamic Gait Index change from baseline to 12 weeks was significantly different in the groups (p = .029). The number of reported falls declined from 0.92 to 0.54 per participant. A supervised group session intervention can increase mobility and gait and reduce fall rate for HF patients. This study was designed to improve lower extremity strength, balance, and falls in elderly HF patients, thus reducing costs and improving quality of life for this population.

Analysis and experimental study on hydraulic balance characteristics in density lock

International Nuclear Information System (INIS)

Gu Haifeng; Yan Changqi; Sun Furong

2009-01-01

Through the simplified theoretical model, the hydraulic balance condition which should be met in the density lock is obtained, when reactor operates normally and density lock is closed. The main parameters influencing this condition are analyzed, and the results show that the hydraulic balance in the density lock is characterized with self-stability in a certain range. Meantime, a simulating experimental loop is built and experimental verification on the self-stability characteristic is done. Moreover, experimental study is done on the conditions of flow change of work fluids in the primary circuit in the process of stable operations. The experimental results show that the hydraulic balance in the density lock can recovered quickly, depending on the self-stability characteristic without influences on the sealing performance of density lock and normal operation of reactor, after the change of operation parameters breaks the hydraulic balance. (authors)

Energy partitioning in dairy cows : effects of lipogenic and glucogenic diets on energy balance, metabolites and reproduction variables in early lactation

NARCIS (Netherlands)

Knegsel, van A.T.M.

2007-01-01

Keywords: dairy cows; dietary energy source; glucogenic nutrients; lipogenic nutrients; negative energy balance; metabolic disorders; reproduction, immune system Dairy cows experience a negative energy balance (NEB) in early lactation which results from high energy requirements for milk production

[Impact of a simultaneous application of anionic salts and rumen buffer on acid-base-balance and mineral metabolism in dairy cows].

Science.gov (United States)

Gelfert, Carl-Christian; Hauser, Simone; Löptien, Antje; Montag, Nicole; Passmann, Mareike; Baumgartner, Walter; Staufenbiel, Rudolf

2006-01-01

In this study, the influence of simultaneous application of anionic salts (AS) and rumen buffer (RB) on the metabolism of dairy cows was examined. Eleven rumen fistulated, non-pregnant and non-lactating dairy cows received equal amounts of one AS (CaCl2 or CaSO4) and one RB (NaHCO3 or KHCO3) via rumen cannula during feeding time over a period of eight days. Before the first application of AS and RB and on day eight of the treatment period, blood, urine and rumen fluid samples were taken. The following parameters were measured: whole blood: pH, base excess, bicarbonate; serum: sodium, potassium, chloride, calcium; urine: pH, net acid base excretion, sodium, potassium, chloride, calcium; rumen fluid: pH. The changes of each parameter were compared via ANOVA. The changes in acid-base balance on day eight were very small, although significant. But p-values showed that the statistical evidence was low. The most changes occurred when NaHCO3 was fed in combination with one of the AS used. In this case a small acidogenic load was seen in blood (p buffer must not be fed, if anionic salts are given for prevention of parturient paresis.

Applications of deuterium labeling in studies of drug metabolism: metabolism of trideuteroaniline mustard

International Nuclear Information System (INIS)

Cox, P.J.; Farmer, P.B.; Foster, A.B.; Jarman, M.

1977-01-01

In a continuation of a study of aniline mustard, the metabolism of 2,4,6-trideuteroaniline mustard [N-N-di-(2-chloroethyl)-2,4,6-trideuteroaniline] was investigated. Measurements of the ratios of deuterated to nondeuterated species in p-hydroxyaniline mustard and N-(2-chloroethyl)-4-hydroxyaniline isolated following in vitro metabolism of a mixture of aniline mustard and aniline mustard-d 3 enabled a determination both of the kinetic isotope effect and of the extents of NIH shifts and indicated the probable metabolite sequence

Temporal dynamics and regulation of lake metabolism

DEFF Research Database (Denmark)

Stæhr, Peter Anton; Jensen, Kaj Sand

2007-01-01

and minima from fall to spring after broad-scale changes in irradiance, temperature, mixing depth, and biomass and growth rate of the algal community and concentrations of inorganic nutrients. Lake metabolism was annually balanced (mean GPP :R 1.04 in 2003 and 1.01 in 2004), with net autotrophy occurring...

Balance and gait in older electroconvulsive therapy recipients: a pilot study

Directory of Open Access Journals (Sweden)

Plakiotis C

2013-06-01

Full Text Available Chris Plakiotis,1,2 Fay Barson,2 Bharathi Vengadasalam,3 Terry P Haines,4 Daniel W O'Connor1,2 1School of Psychology and Psychiatry, Monash University, Melbourne, VIC, Australia; 2MonashHealth, Melbourne, VIC, Australia; 3Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 4Allied Health Research Unit, Monash University and MonashHealth, Melbourne, VIC, Australia Background: Electroconvulsive therapy (ECT is commonly used to treat depression in older adults. Despite its efficacy in this regard, an associated increase in the risk of falls in this population is a downside of treatment. ECT research has focused on the incidence of falls, but its effect on balance and gait – intrinsic factors in instability and falls – has not been studied. Our aim was to examine changes in balance and gait among older adults before and after a single ECT session and explore the effect of patient-related and treatment factors on any changes found. Methods: Participants were 21 older adults requiring ECT for depression in public psychiatric services. Patients with clinically overt mobility problems (impairing test participation or increasing the risk of falls were excluded. Balance and gait testing 1 hour pre-ECT and 1, 2 and 3 hours post-ECT included: (1 steady standing test; (2 perturbation of standing balance by self-initiated movements; (3 perturbation of standing balance by an external perturbation; and (4 timed up and go test. Results: No deterioration in test performance was found, using one-way repeated measures analysis of variance. Conclusion: Balance and gait did not deteriorate immediately after ECT. Exclusion of participants with clinically overt mobility problems and falls being better attributable to factors unrelated to balance and gait (such as post-ECT confusion may account for our findings. This research does not repudiate the occurrence of ECT-related falls but calls into question the utility of introducing routine balance and gait

Pheromone-sensing neurons regulate peripheral lipid metabolism in Caenorhabditis elegans.

Science.gov (United States)

Hussey, Rosalind; Stieglitz, Jon; Mesgarzadeh, Jaleh; Locke, Tiffany T; Zhang, Ying K; Schroeder, Frank C; Srinivasan, Supriya

2017-05-01

It is now established that the central nervous system plays an important role in regulating whole body metabolism and energy balance. However, the extent to which sensory systems relay environmental information to modulate metabolic events in peripheral tissues has remained poorly understood. In addition, it has been challenging to map the molecular mechanisms underlying discrete sensory modalities with respect to their role in lipid metabolism. In previous work our lab has identified instructive roles for serotonin signaling as a surrogate for food availability, as well as oxygen sensing, in the control of whole body metabolism. In this study, we now identify a role for a pair of pheromone-sensing neurons in regulating fat metabolism in C. elegans, which has emerged as a tractable and highly informative model to study the neurobiology of metabolism. A genetic screen revealed that GPA-3, a member of the Gα family of G proteins, regulates body fat content in the intestine, the major metabolic organ for C. elegans. Genetic and reconstitution studies revealed that the potent body fat phenotype of gpa-3 null mutants is controlled from a pair of neurons called ADL(L/R). We show that cAMP functions as the second messenger in the ADL neurons, and regulates body fat stores via the neurotransmitter acetylcholine, from downstream neurons. We find that the pheromone ascr#3, which is detected by the ADL neurons, regulates body fat stores in a GPA-3-dependent manner. We define here a third sensory modality, pheromone sensing, as a major regulator of body fat metabolism. The pheromone ascr#3 is an indicator of population density, thus we hypothesize that pheromone sensing provides a salient 'denominator' to evaluate the amount of food available within a population and to accordingly adjust metabolic rate and body fat levels.

MECHANISMS IN ENDOCRINOLOGY: Nutrition as a mediator of oxidative stress in metabolic and reproductive disorders in women.

Science.gov (United States)

Diamanti-Kandarakis, Evanthia; Papalou, Olga; Kandaraki, Eleni A; Kassi, Georgia

2017-02-01

Nutrition can generate oxidative stress and trigger a cascade of molecular events that can disrupt oxidative and hormonal balance. Nutrient ingestion promotes a major inflammatory and oxidative response at the cellular level in the postprandial state, altering the metabolic state of tissues. A domino of unfavorable metabolic changes is orchestrated in the main metabolic organs, including adipose tissue, skeletal muscle, liver and pancreas, where subclinical inflammation, endothelial dysfunction, mitochondrial deregulation and impaired insulin response and secretion take place. Simultaneously, in reproductive tissues, nutrition-induced oxidative stress can potentially violate delicate oxidative balance that is mandatory to secure normal reproductive function. Taken all the above into account, nutrition and its accompanying postprandial oxidative stress, in the unique context of female hormonal background, can potentially compromise normal metabolic and reproductive functions in women and may act as an active mediator of various metabolic and reproductive disorders. © 2017 European Society of Endocrinology.

A preliminary study of static and dynamic balance in sedentary obese young adults: the relationship between BMI, posture and postural balance.

Science.gov (United States)

do Nascimento, J A; Silva, C C; Dos Santos, H H; de Almeida Ferreira, J J; de Andrade, P R

2017-12-01

The aim of this study was to evaluate the postural control of obese young adults with normal body mass index during different static (bipedic and unipedic support) and dynamic postural conditions (gait velocity and limits of stability) in order to compare the static and dynamic balance of these individuals. A cross-sectional quantitative study was carried out to evaluate static and dynamic balance in 25 sedentary individuals. The sample was divided into two groups, 10 in the normal-weight group (24.70 ± 3.89 years and 21.5 ± 1.66 kg m -2 ) and 15 in the obese group (26.80 ± 5.16 years and 35.66 ± 4.29 kg m -2 ). Postural evaluation was performed through visual inspection, and balance analyses were performed using the Timed Up & Go test (TUGT) and Balance System (Biodex). Descriptive analyses, Fisher's exact test and Mann Whitney U-tests were performed using the Statistical Package for Social Sciences (SPSS - 20.0, Armonk, NY) software. Most of the obese volunteers presented postural alterations, such as head protrusion (47.6%), hyperkyphosis (46.7%) and hyperlordosis (26.7%). Medial-lateral dynamic displacement, risk of falls and mean time to perform the limits of stability test and TUGT were higher for obese subjects (P  0.05) for static balance tests for either bipedal or unipedal tasks. The disadvantage presented by the young obese subjects occurs in dynamic activities, representing worse balance and an increase in time needed to accomplish these activities. © 2017 World Obesity Federation.

History of Medical Understanding and Misunderstanding of Acid Base Balance

Science.gov (United States)

Aiken, Christopher Geoffrey Alexander

2013-01-01

To establish how controversies in understanding acid base balance arose, the literature on acid base balance was reviewed from 1909, when Henderson described how the neutral reaction of blood is determined by carbonic and organic acids being in equilibrium with an excess of mineral bases over mineral acids. From 1914 to 1930, Van Slyke and others established our acid base principles. They recognised that carbonic acid converts into bicarbonate all non-volatile mineral bases not bound by mineral acids and determined therefore that bicarbonate represents the alkaline reserve of the body and should be a physiological constant. They showed that standard bicarbonate is a good measure of acidosis caused by increased production or decreased elimination of organic acids. However, they recognised that bicarbonate improved low plasma bicarbonate but not high urine acid excretion in diabetic ketoacidosis, and that increasing pCO2 caused chloride to shift into cells raising plasma titratable alkali. Both indicate that minerals influence pH. In 1945 Darrow showed that hyperchloraemic metabolic acidosis in preterm infants fed milk with 5.7 mmol of chloride and 2.0 mmol of sodium per 100 kcal was caused by retention of chloride in excess of sodium. Similar findings were made but not recognised in later studies of metabolic acidosis in preterm infants. Shohl in 1921 and Kildeberg in 1978 presented the theory that carbonic and organic acids are neutralised by mineral base, where mineral base is the excess of mineral cations over anions and organic acid is the difference between mineral base, bicarbonate and protein anion. The degree of metabolic acidosis measured as base excess is determined by deviation in both mineral base and organic acid from normal. PMID:24179938

Flux Balance Analysis of Escherichia coli under Temperature and pH Stress Conditions

KAUST Repository

Xu, Xiaopeng

2015-05-12

An interesting discovery in biology is that most genes in an organism are dispensable. That means these genes have minor effects on survival of the organism in standard laboratory conditions. One explanation of this discovery is that some genes play important roles in specific conditions and are essential genes under those conditions. E. coli is a model organism, which is widely used. It can adapt to many stress conditions, including temperature, pH, osmotic, antibiotic, etc. Underlying mechanisms and associated genes of each stress condition responses are usually different. In our analysis, we combined protein abundance data and mutant conditional fitness data into E. coli constraint-based metabolic models to study conditionally essential metabolic genes under temperature and pH stress conditions. Flux Balance Analysis was employed as the modeling method to analysis these data. We discovered lists of metabolic genes, which are E. coli dispensable genes, but conditionally essential under some stress conditions. Among these conditionally essential genes, atpA in low pH stress and nhaA in high pH stress found experimental evidences from previous studies. Our study provides new conditionally essential gene candidates for biologists to explore stress condition mechanisms.

Essential role of UCP1 modulating the central effects of thyroid hormones on energy balance

Directory of Open Access Journals (Sweden)

Mayte Alvarez-Crespo

2016-04-01

Full Text Available Objective: Classically, metabolic effects of thyroid hormones (THs have been considered to be peripherally mediated, i.e. different tissues in the body respond directly to thyroid hormones with an increased metabolism. An alternative view is that the metabolic effects are centrally regulated. We have examined here the degree to which prolonged, centrally infused triiodothyronine (T3 could in itself induce total body metabolic effects and the degree to which brown adipose tissue (BAT thermogenesis was essential for such effects, by examining uncoupling protein 1 (UCP1 KO mice. Methods: Wildtype and UPC1 KO mice were centrally-treated with T3 by using minipumps. Metabolic measurements were analyzed by indirect calorimetry and expression analysis by RT-PCR or western blot. BAT morphology and histology were studied by immunohistochemistry. Results: We found that central T3-treatment led to reduced levels of hypothalamic AMP-activated protein kinase (AMPK and elevated body temperature (0.7 °C. UCP1 was essential for the T3-induced increased rate of energy expenditure, which was only observable at thermoneutrality and notably only during the active phase, for the increased body weight loss, for the increased hypothalamic levels of neuropeptide Y (NPY and agouti-related peptide (AgRP and for the increased food intake induced by central T3-treatment. Prolonged central T3-treatment also led to recruitment of BAT and britening/beiging (“browning” of inguinal white adipose tissue (iWAT. Conclusions: We conclude that UCP1 is essential for mediation of the central effects of thyroid hormones on energy balance, and we suggest that similar UCP1-dependent effects may underlie central energy balance effects of other agents. Keywords: AMPK, Brown adipose tissue, Hypothalamus, Thyroid hormones, UCP1

Tai Chi and balance control.

Science.gov (United States)

Wong, Alice M K; Lan, Ching

2008-01-01

Balance function begins to decline from middle age on, and poor balance function increases the risk of fall and injury. Suitable exercise training may improve balance function and prevent accidental falls. The coordination of visual, proprioceptive, vestibular and musculoskeletal system is important to maintain balance. Balance function can be evaluated by functional balance testing and sensory organization testing. Tai Chi Chuan (TC) is a popular conditioning exercise in the Chinese community, and recent studies substantiate that TC is effective in balance function enhancement and falls prevention. In studies utilizing functional balance testing, TC may increase the duration of one-leg standing and the distance of functional reach. In studies utilizing sensory organization testing, TC improves static and dynamic balance, especially in more challenging sensory perturbed condition. Therefore, TC may be prescribed as an alternative exercise program for elderly subjects or balance-impaired patients. Participants can choose to perform a complete set of TC or selected movements according to their needs. In conclusion, TC may improve balance function and is appropriate for implementation in the community.

Gut Microbiota: Association with NAFLD and Metabolic Disturbances

Directory of Open Access Journals (Sweden)

E. Lau

2015-01-01

Full Text Available Nonalcoholic fatty liver disease is the hepatic expression of metabolic syndrome, being frequently associated with obesity, insulin resistance, and dyslipidemia. Recent lines of evidence have demonstrated a role of gut microbiota in insulin resistance, obesity, and associated metabolic disturbances, raising the interest in its relationship with NAFLD pathogenesis. Therefore, intestinal microbiota has emerged as a potential factor involved in NAFLD, through different pathways, including its influence in energy storage, lipid and choline metabolism, ethanol production, immune balance, and inflammation. The main objective of this review is to address the pathogenic association of gut microbiota to NAFLD. This comprehension may allow the development of integrated strategies to modulate intestinal microbiota in order to treat NAFLD.

Net community production and metabolic balance at the oligotrophic ocean site, station ALOHA

Science.gov (United States)

le B. Williams, Peter J.; Morris, Paul J.; Karl, David M.

2004-11-01

To test the hypothesis that in oligotrophic areas of the ocean respiration exceeds production, a 12-month study was undertaken of in vitro-determined net oxygen production and consumption in the top 150 m of the water column at the extreme oligotrophic site, Station ALOHA, in the North Pacific subtropical gyre. Throughout the year the water column was observed to be in metabolic deficit, the calculated cumulative shortfall being 9±1.7 mol O2 m-2 a-1 (approximately 100 g C m-2 a-1), an amount equivalent to 40% of measured production (annual estimated rates of production and consumption were, respectively, 22 and 31 mol O2 m-2 a-1). We consider three possible explanations for the observed deficit: the in vitro oxygen rate measurements, in themselves, are fundamentally flawed and should be discounted, the observations are correct and the observed deficit is a true account of the balance of oxygen (and organic carbon) at Station ALOHA, or the observations are correct as they stand, but need not be interpreted as organic carbon imbalance for that ecosystem. We find no error unique to the oxygen rate measurements themselves. We find also no evidence that the associated organic carbon deficit can be sustained over the long-term by internal organic reserves or by external subsidy. Accordingly we accept the geochemical findings that calculated in situ oxygen flux requires the euphotic zone of the water column at this site to be slightly (circa 2 mol C m-2 a-1) autotrophic, in contrast to the simple analysis of our observations which gives a net heterotrophic water column. We discuss a number of processes that may give rise to the observed discrepancy. In part it may derive from the difficulty of reproducing the variations in the light field experienced by an algal cell due to vertical advection. It may also derive from the intermittency of production. This latter effect would manifest itself in the following manner. Because of its universal distribution in the food web

Practical implementation of Wilhelm Osbahr’s entrepreneur balance sheet theory assumptions – the case study

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Ewa Śnieżek

2015-12-01

Full Text Available The aim of this study is to present the possibilities of the practical application of Osbahr’s balance sheet theoryassumptions, as one of many possible attempts to close the information gap in the financial reporting of thetwenty-first century. Wilhelm Osbahr, at the beginning of the 20th century, made an attempt to solve the problemof indicating the balance sheet values (the impact of balance sheet evaluation on the balance sheet items,from the point of view of an entrepreneur or business owner, at the same time clearly emphasizing the necessityto deal with the balance sheet structure through the prism of the objectives pursued by the company. Osbahrpostulated highlighting any changes occurring in the economic structure of the company and its components,which do not result directly from its operating activities, and so to present them in the position called “adjustments”.This article uses the deductive method supported by literature studies and a case study method. Theauthors using the case study method confirm the possibility of using the described balance sheet theory in thecurrent financial reporting based on actual data of the company ABC Ltd. They also show that a balance sheetwhich is presented according to the new reporting formula discloses new quality of information for the financialreporting users.

A simulation of cross-country skiing on varying terrain by using a mathematical power balance model.

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Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

2013-01-01

The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%-4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing.

Increased fat catabolism sustains water balance during fasting in zebra finches.

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Rutkowska, Joanna; Sadowska, Edyta T; Cichoń, Mariusz; Bauchinger, Ulf

2016-09-01

Patterns of physiological flexibility in response to fasting are well established, but much less is known about the contribution of water deprivation to the observed effects. We investigated body composition and energy and water budget in three groups of zebra finches: birds with access to food and water, food-deprived birds having access to drinking water and food-and-water-deprived birds. Animals were not stimulated by elevated energy expenditure and they were in thermoneutral conditions; thus, based on previous studies, water balance of fasting birds was expected to be maintained by increased catabolism of proteins. In contrast to this expectation, we found that access to water did not prevent reduction of proteinaceous tissue, but it saved fat reserves of the fasting birds. Thus, water balance of birds fasting without access to water seemed to be maintained by elevated fat catabolism, which generated 6 times more metabolic water compared with that in birds that had access to water. Therefore, we revise currently established views and propose fat to serve as the primary source for metabolic water production. Previously assumed increased protein breakdown for maintenance of water budget would occur if fat stores were depleted or if fat catabolism reached its upper limits due to high energy demands. © 2016. Published by The Company of Biologists Ltd.

Effects of sodium bicarbonate and 1,25-dihydroxy-cholecalciferol on calcium and phosphorus balances in the rat

International Nuclear Information System (INIS)

Goulding, A.; McIntosh, J.; Campbell, D.

1984-01-01

Metabolic balance studies were undertaken to determine whether sodium bicarbonate (NaHCO 3 ) supplements (4.5 mmol/day) altered 7-day cumulative calcium (Ca) phosphorus (P) balances in growing rats consuming either a basal diet providing 0.6% Ca and 0.3% P, or this diet plus 1,25-dihydroxycholecalciferol [40 ng 1,25(OH) 2 D 3 /day]. Feeding bicarbonate lowered urinary Ca but raised fecal Ca so that Ca balance became less positive. However, 1,25(OH) 2 D 3 increased net absorption of Ca and P to the same degree when given to control rats and rats consuming bicarbonate. Nevertheless, bicarbonate-fed rats had lower net Ca absorption than controls, even when treated with high doses of 1,25(OH) 2 D 3 . Changes in net Ca absorption induced by bicarbonate may occur at a point in the gut distal to the duodenum since duodenal 45 Ca absorption was decreased by bicarbonate feeding. The present results show that bicarbonate consumption depressed net Ca absorption in the rat. The effect appears to be independent of changes in 1,25(OH) 2 D 3 metabolism because it is manifest in animals receiving high doses of 1,25(OH) 2 D 3 , which stimulate alimentary Ca absorption maximally, and because bicarbonate-fed rats are able to respond normally to exogenous 1,25(OH) 2 D 3 by increasing their net absorption of Ca and P. In view of this demonstration that NaHCO 3 supplements elevate fecal Ca loss in the rat, it is suggested that studies should be undertaken to determine whether bicarbonate exerts similar adverse effects on Ca balance in humans

Efficacy of an extravascular lung water-driven negative fluid balance protocol.

Science.gov (United States)

Díaz-Rubia, L; Ramos-Sáez, S; Vázquez-Guillamet, R; Guerrero-López, F; Pino-Sánchez, F; García-Delgado, M; Gómez-Jiménez, F J; Fernández-Mondéjar, E

2015-01-01

To analyze the efficacy of negative fluid balance in hypoxemic patients with an elevated extravascular lung water index (EVLWI). A retrospective observational study was made. Intensive Care Unit of Virgen de las Nieves Hospital (Spain). Forty-four patients participated in the study. We analyzed our database of hypoxemic patients covering a period of 11 consecutive months. We included all hemodynamically stable and hypoxemic patients with EVLWI>9ml/kg. The protocol dictates a negative fluid balance between 500 and 1500ml/day. We analyzed the impact of this negative fluid balance strategy upon pulmonary, hemodynamic, and renal function. Demographic data, severity scores, clinical, hemodynamic, pulmonary, metabolic and renal function data. Thirty-three patients achieved negative fluid balance (NFB group) and 11 had a positive fluid balance (PFB group). In the former group, PaO2/FiO2 improved from 145 (IQR 106, 200) to 210mmHg (IQR 164, 248) (pPFB group, EVLWI also decreased from 11 (10, 14) to 10ml/kg (8, 14) at the end of the protocol (p=0.004). For these patients there were no changes in oxygenation, with a PaO2/FiO2 of 216mmHg (IQR 137, 260) at the beginning versus 205mmHg (IQR 99,257) at the end of the study (p=0.08). Three out of four hypoxic patients with elevated EVLWI tolerated the NFB protocol. In these subjects, the improvement of various analyzed physiological parameters was greater and faster than in those unable to complete the protocol. Patients who did not tolerate the protocol were usually in more severe condition, though a larger sample would be needed to detect specific characteristics of this group. Copyright © 2014 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

PENGARUH WORK-LIFE BALANCE TERHADAP KEPUASAN KERJA KARYAWAN (STUDI PADA PT. BIO FARMA PERSERO

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I Made Devan Ganapathi

2016-04-01

Full Text Available Abstrak - Sumber daya manusia merupakan sumber daya yang berperan penting dalam rangka mencapai tujuan perusahaan. Pengelolaan sumber daya manusia yang baik akan berdampak positif bagi perusahaan yang bersangkutan. Penelitian ini dilakukan untuk mengetahui pengaruh Work-Life Balance terhadap kepuasan kerja karyawan pada PT. Bio Farma (Persero. Work-Life Balance sebagai variabel bebas terdiri dari tiga keseimbangan yaitu keseimbangan waktu, keseimbangan keterlibatan dan keseimbangan kepuasan. Adapun kepuasan kerja sebagai variabel terikat dibagi menjadi empat faktor yaitu faktor psikologis, faktor sosial, faktor fisik dan faktor finansial. Jenis penelitian ini menggunakan metode deskriptif dan kausal. Data yang digunakan dalam penelitian ini adalah data primer yang diperoleh dari wawancara dan kuesioner yang disebarkan kepada 92 responden serta data sekunder berupa dokumen dari perusahaan. Teknik pengumpulan sampel yang digunakan adalah simple random sampling. Metode analisis data yang digunakan adalah regresi linier berganda. Untuk menganalisis data tersebut dibantu menggunakan program SPSS. Hasil dari penelitian ini menunjukkan bahwa Work-Life Balance berpengaruh secara simultan terhadap kepuasan kerja karyawan sebesar 42,2% dan sisanya 57,8% dipengaruhi oleh variabel lain yang tidak diteliti pada penelitian ini. Secara parsial, keseimbangan kepuasan berpengaruh secara signifikan terhadap kepuasan kerja karyawan. Sedangkan keseimbangan waktu dan keseimbangan keterlibatan tidak berpengaruh secara signifikan terhadap kepuasan kerja karyawan. Kata Kunci : work-life balance, kepuasan kerja karyawan, keseimbangan kepuasan. Abstract - Human resource is a resource that plays an important role in order to achieve the company's goals. Good management of the human resource will have a positive impact for the company concerned. This study was conducted to determine the effect of Work-Life Balance on job satisfaction of employees at PT. Bio Farma (Persero

Partitioning the Metabolic Cost of Human Running: A Task-by-Task Approach

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Arellano, Christopher J.; Kram, Rodger

2014-01-01

Compared with other species, humans can be very tractable and thus an ideal “model system” for investigating the metabolic cost of locomotion. Here, we review the biomechanical basis for the metabolic cost of running. Running has been historically modeled as a simple spring-mass system whereby the leg acts as a linear spring, storing, and returning elastic potential energy during stance. However, if running can be modeled as a simple spring-mass system with the underlying assumption of perfect elastic energy storage and return, why does running incur a metabolic cost at all? In 1980, Taylor et al. proposed the “cost of generating force” hypothesis, which was based on the idea that elastic structures allow the muscles to transform metabolic energy into force, and not necessarily mechanical work. In 1990, Kram and Taylor then provided a more explicit and quantitative explanation by demonstrating that the rate of metabolic energy consumption is proportional to body weight and inversely proportional to the time of foot-ground contact for a variety of animals ranging in size and running speed. With a focus on humans, Kram and his colleagues then adopted a task-by-task approach and initially found that the metabolic cost of running could be “individually” partitioned into body weight support (74%), propulsion (37%), and leg-swing (20%). Summing all these biomechanical tasks leads to a paradoxical overestimation of 131%. To further elucidate the possible interactions between these tasks, later studies quantified the reductions in metabolic cost in response to synergistic combinations of body weight support, aiding horizontal forces, and leg-swing-assist forces. This synergistic approach revealed that the interactive nature of body weight support and forward propulsion comprises ∼80% of the net metabolic cost of running. The task of leg-swing at most comprises ∼7% of the net metabolic cost of running and is independent of body weight support and forward

Metabolic Desynchronization in Critical Conditions: Experimental Study

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G. V. Livanov

2006-01-01

Full Text Available Objective. To conduct an experimental study of the impact of the time of administration of succinic acid preparations on central nervous system (CNS function and gas exchange while simulating metabolic therapy for severe poisoning by ethyl alcohol. The study was performed on 74 male albino rats weighing 140—180 g. Acute severe and very severe intoxication was simulated, by intraabdominally administering 30% ethanol to the rats. Cytoflavin was used to simulate experimental therapy. The rate of gas exchange was estimated by the oxygen uptake determined by the closed chamber method in a Regnault apparatus (Germany. Spontaneous bioelectrical activity was recorded in the frontooccipital lead by the routine procedure. External pain stimulation and rhythmical photostimulation were employed to evaluate cerebral responsiveness. Heterodirectional EEG changes in the «early» and «late» administration of succinate were not followed by the similar alterations of gas exchange: oxygen consumption in both the «early» and «late» administration of succinate remained significantly lower than in the control animals. With the late administration of succinate to the animals with mixed (toxic and hypoxic coma, the so-called discrepancy between the noticeably increased energy production and brutally diminished metabolism occurred. It may be just the pathological mechanism that was the basis for higher mortality in the late succinate administration group. The findings and their analysis make it possible to advance a hypothesis that succinate may cause metabolic desynchronization if activation of metabolic processes takes place under severe tissue respiratory tissue depression. In these cases, there is a severe damage to tissue and chiefly the brain. This manifests itself as EEG epileptiform activity splashes preceding the animals’ death. Therefore, resuscitation aimed at restoring the transport of oxygen and its involvement in tissue energy processes should

One-Carbon Metabolism in Prostate Cancer: The Role of Androgen Signaling

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Joshua M. Corbin

2016-07-01

Full Text Available Cancer cell metabolism differs significantly from the metabolism of non-transformed cells. This altered metabolic reprogramming mediates changes in the uptake and use of nutrients that permit high rates of proliferation, growth, and survival. The androgen receptor (AR plays an essential role in the establishment and progression of prostate cancer (PCa, and in the metabolic adaptation that takes place during this progression. In its role as a transcription factor, the AR directly affects the expression of several effectors and regulators of essential catabolic and biosynthetic pathways. Indirectly, as a modulator of the one-carbon metabolism, the AR can affect epigenetic processes, DNA metabolism, and redox balance, all of which are important factors in tumorigenesis. In this review, we focus on the role of AR-signaling on one-carbon metabolism in tumorigenesis. Clinical implications of one-carbon metabolism and AR-targeted therapies for PCa are discussed in this context.

One-Carbon Metabolism in Prostate Cancer: The Role of Androgen Signaling

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Corbin, Joshua M.; Ruiz-Echevarría, Maria J.

2016-01-01

Cancer cell metabolism differs significantly from the metabolism of non-transformed cells. This altered metabolic reprogramming mediates changes in the uptake and use of nutrients that permit high rates of proliferation, growth, and survival. The androgen receptor (AR) plays an essential role in the establishment and progression of prostate cancer (PCa), and in the metabolic adaptation that takes place during this progression. In its role as a transcription factor, the AR directly affects the expression of several effectors and regulators of essential catabolic and biosynthetic pathways. Indirectly, as a modulator of the one-carbon metabolism, the AR can affect epigenetic processes, DNA metabolism, and redox balance, all of which are important factors in tumorigenesis. In this review, we focus on the role of AR-signaling on one-carbon metabolism in tumorigenesis. Clinical implications of one-carbon metabolism and AR-targeted therapies for PCa are discussed in this context. PMID:27472325

Influence of intranasal and carotid cooling on cerebral temperature balance and oxygenation

DEFF Research Database (Denmark)

Nybo, Lars; Wanscher, Michael; Secher, Niels H.

2014-01-01

temperatures were measured to assess the cerebral heat balance and corresponding paired blood samples were obtained to evaluate cerebral metabolism and oxygenation at rest, following 60 min of intranasal cooling, 5 min of nasal ventilation, and 15 min with carotid cooling. Intranasal cooling induced a parallel......The present study evaluated the influence of intranasal cooling with balloon catheters, increased nasal ventilation, or percutaneous cooling of the carotid arteries on cerebral temperature balance and oxygenation in six healthy male subjects. Aortic arch and internal jugular venous blood...... drop in jugular venous and arterial blood temperatures by 0.30 ± 0.08°C (mean ± SD), whereas nasal ventilation and carotid cooling failed to lower the jugular venous blood temperature. The magnitude of the arterio-venous temperature difference across the brain remained unchanged at -0.33 ± 0.05°C...

Linking neuronal brain activity to the glucose metabolism.

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Göbel, Britta; Oltmanns, Kerstin M; Chung, Matthias

2013-08-29

Energy homeostasis ensures the functionality of the entire organism. The human brain as a missing link in the global regulation of the complex whole body energy metabolism is subject to recent investigation. The goal of this study is to gain insight into the influence of neuronal brain activity on cerebral and peripheral energy metabolism. In particular, the tight link between brain energy supply and metabolic responses of the organism is of interest. We aim to identifying regulatory elements of the human brain in the whole body energy homeostasis. First, we introduce a general mathematical model describing the human whole body energy metabolism. It takes into account the two central roles of the brain in terms of energy metabolism. The brain is considered as energy consumer as well as regulatory instance. Secondly, we validate our mathematical model by experimental data. Cerebral high-energy phosphate content and peripheral glucose metabolism are measured in healthy men upon neuronal activation induced by transcranial direct current stimulation versus sham stimulation. By parameter estimation we identify model parameters that provide insight into underlying neurophysiological processes. Identified parameters reveal effects of neuronal activity on regulatory mechanisms of systemic glucose metabolism. Our examinations support the view that the brain increases its glucose supply upon neuronal activation. The results indicate that the brain supplies itself with energy according to its needs, and preeminence of cerebral energy supply is reflected. This mechanism ensures balanced cerebral energy homeostasis. The hypothesis of the central role of the brain in whole body energy homeostasis as active controller is supported.

Metabolic responses of Haliotis diversicolor to Vibrio parahaemolyticus infection.

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Lu, Jie; Shi, Yanyan; Cai, Shuhui; Feng, Jianghua

2017-01-01

Vibrio parahemolyticus is a devastating bacterial pathogen that often causes outbreak of vibriosis in abalone Haliotis diversicolor. Elucidation of metabolic mechanisms of abalones in responding to V. parahemolyticus infection is essential for controlling the epidemic. In this work, 1 H NMR-based metabolomic techniques along with correlation and network analyses are used to investigate characteristic metabolites, as well as corresponding disturbed pathways in hepatopancreas and gill of H. diversicolor after V. parahemolyticus infection for 48 h. Results indicate that obvious gender- and tissue-specific metabolic responses are induced. Metabolic responses in female abalones are more clearly observed than those in males, which are primarily manifested in the accumulation of branched-chain amino acids and the depletion of organic osmolytes (homarine, betaine and taurine) in the infected gills of female abalones, as well as in the depletion of glutamate, branched-chain and aromatic amino acids in the infected hepatopancreases of female abalones. Moreover, based on major metabolic functions of the characteristic metabolites, we have found that V. parahemolyticus infection not only cause the disturbance in energy metabolism, nucleotide metabolism and osmotic balance, but also induce oxidative stress, immune stress and neurotoxic effect in different tissues with various mechanisms. Our study provides details of metabolic responses of abalones to V. parahemolyticus infection and will shed light on biochemical defence mechanisms of male and female hosts against pathogen infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

Metabolic vs. hedonic obesity: a conceptual distinction and its clinical implications.

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Yu, Y-H; Vasselli, J R; Zhang, Y; Mechanick, J I; Korner, J; Peterli, R

2015-03-01

Body weight is determined via both metabolic and hedonic mechanisms. Metabolic regulation of body weight centres around the 'body weight set point', which is programmed by energy balance circuitry in the hypothalamus and other specific brain regions. The metabolic body weight set point has a genetic basis, but exposure to an obesogenic environment may elicit allostatic responses and upward drift of the set point, leading to a higher maintained body weight. However, an elevated steady-state body weight may also be achieved without an alteration of the metabolic set point, via sustained hedonic over-eating, which is governed by the reward system of the brain and can override homeostatic metabolic signals. While hedonic signals are potent influences in determining food intake, metabolic regulation involves the active control of both food intake and energy expenditure. When overweight is due to elevation of the metabolic set point ('metabolic obesity'), energy expenditure theoretically falls onto the standard energy-mass regression line. In contrast, when a steady-state weight is above the metabolic set point due to hedonic over-eating ('hedonic obesity'), a persistent compensatory increase in energy expenditure per unit metabolic mass may be demonstrable. Recognition of the two types of obesity may lead to more effective treatment and prevention of obesity. © 2015 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of International Association for the Study of Obesity (IASO).

Metabolic and inflammatory profiles of biomarkers in obesity, metabolic syndrome, and diabetes in a Mediterranean population. DARIOS Inflammatory study.

Science.gov (United States)

Fernández-Bergés, Daniel; Consuegra-Sánchez, Luciano; Peñafiel, Judith; Cabrera de León, Antonio; Vila, Joan; Félix-Redondo, Francisco Javier; Segura-Fragoso, Antonio; Lapetra, José; Guembe, María Jesús; Vega, Tomás; Fitó, Montse; Elosua, Roberto; Díaz, Oscar; Marrugat, Jaume

2014-08-01

There is a paucity of data regarding the differences in the biomarker profiles of patients with obesity, metabolic syndrome, and diabetes mellitus as compared to a healthy, normal weight population. We aimed to study the biomarker profile of the metabolic risk continuum defined by the transition from normal weight to obesity, metabolic syndrome, and diabetes mellitus. We performed a pooled analysis of data from 7 cross-sectional Spanish population-based surveys. An extensive panel comprising 20 biomarkers related to carbohydrate metabolism, lipids, inflammation, coagulation, oxidation, hemodynamics, and myocardial damage was analyzed. We employed age- and sex-adjusted multinomial logistic regression models for the identification of those biomarkers associated with the metabolic risk continuum phenotypes: obesity, metabolic syndrome, and diabetes mellitus. A total of 2851 subjects were included for analyses. The mean age was 57.4 (8.8) years, 1269 were men (44.5%), and 464 participants were obese, 443 had metabolic syndrome, 473 had diabetes mellitus, and 1471 had a normal weight (healthy individuals). High-sensitivity C-reactive protein, apolipoprotein B100, leptin, and insulin were positively associated with at least one of the phenotypes of interest. Apolipoprotein A1 and adiponectin were negatively associated. There are differences between the population with normal weight and that having metabolic syndrome or diabetes with respect to certain biomarkers related to the metabolic, inflammatory, and lipid profiles. The results of this study support the relevance of these mechanisms in the metabolic risk continuum. When metabolic syndrome and diabetes mellitus are compared, these differences are less marked. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

AN INITIAL EVALUATION OF THE BTRACKS BALANCE PLATE AND SPORTS BALANCE SOFTWARE FOR CONCUSSION DIAGNOSIS.

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Goble, Daniel J; Manyak, Kristin A; Abdenour, Thomas E; Rauh, Mitchell J; Baweja, Harsimran S

2016-04-01

As recently dictated by the American Medical Society, balance testing is an important component in the clinical evaluation of concussion. Despite this, previous research on the efficacy of balance testing for concussion diagnosis suggests low sensitivity (∼30%), based primarily on the popular Balance Error Scoring System (BESS). The Balance Tracking System (BTrackS, Balance Tracking Systems Inc., San Diego, CA, USA) consists of a force plate (BTrackS Balance Plate) and software (BTrackS Sport Balance) which can quickly (balance testing with gold standard accuracy. The present study aimed to determine the sensitivity of the BTrackS Balance Plate and Sports Balance Software for concussion diagnosis. Cross-Sectional Study. Preseason baseline balance testing of 519 healthy Division I college athletes playing sports with a relatively high risk for concussions was performed with the BTrackS Balance Test. Testing was administered by certified athletic training staff using the BTrackS Balance Plate and Sport Balance software. Of the baselined athletes, 25 later experienced a concussion during the ensuing sport season. Post-injury balance testing was performed on these concussed athletes within 48 of injury and the sensitivity of the BTrackS Balance Plate and Sport Balance software was estimated based on the number of athletes showing a balance decline according to the criteria specified in the Sport Balance software. This criteria is based on the minimal detectable change statistic with a 90% confidence level (i.e. 90% specificity). Of 25 athletes who experienced concussions, 16 had balance declines relative to baseline testing results according to the BTrackS Sport Balance software criteria. This corresponds to an estimated concussion sensitivity of 64%, which is twice as great as that reported previously for the BESS. The BTrackS Balance Plate and Sport Balance software has the greatest concussion sensitivity of any balance testing instrument reported to date. Level 2

Nrg4 promotes fuel oxidation and a healthy adipokine profile to ameliorate diet-induced metabolic disorders

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Zhimin Chen

2017-08-01

Conclusions: Nrg4 exerts pleiotropic beneficial effects on energy balance and glucose and lipid metabolism to ameliorate obesity-associated metabolic disorders. Biologic therapeutics based on Nrg4 may improve both type 2 diabetes and non-alcoholic fatty liver disease (NAFLD in patients.

Complex Evaluation Oxygen Status and Lipid Metabolism Indexes in Newborns with Perinatal Hypoxia and Hypovolemic Shock

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Svetlana A. Perepelitsa

2017-01-01

Full Text Available Aim. To asses of metabolism, lipid metabolism and oxygen status parameters in newborns with perinatal hypoxia.Materials and Methods. 53 newborn babies born with signs of severe hypoxia and low Apgar scoring equal to 2 at the 1st minute of life were enrolled in the study. Newborns were divided into 2 groups depending on the presence of the clinical presentation of shock: Group 1 «Shock» and Group 2 «Acute intranatal hypoxia» (AIH. All newborns underwent testing for blood gas and acid-base balance, lactate level. Cholesterol and triglyceride levels in the central venous blood were also tested immediately after the birth and on the 5th day of life. Mechanical ventilation mode and parameters were registered. The mean airway pressure (MAP and the oxygen saturation index (OSI were calculated.Results. Severe decompensated metabolic lactic acidosis was diagnosed in a «Shock» group newborns at birth, thus indicating severe perinatal hypoxia which had triggered the development of shock. As for the «AIH» group newborns, they had hyperlactatemia alone. The most severe hypoxemia at birth was diagnosed in newborns of the «Shock» group; the OSI value in these infants was significantly higher than that in «AIH» infants (P<0.01. Despite the treatment and mechanical ventilation, during the posthypoxic period, newborns from the «Shock» group were characterized by increased OSI values over 12 hours after birth. Significantly high levels of OSI persisted for 48 hours after the delivery. Severe hypotriglyceridemia and hypocholesterolemia were found in both group newborns.Conclusion. The study demonstrated that there was intranatal complex metabolism impairment in the case of perinatal hypoxia; at birth, it manifested by metabolic acidosis of various degrees of severity and imbalance of triglycerides and cholesterol levels. The longer and more severe hypoxia is, the more severe acid-base balance and blood lactate level impairment at birth become

Practical implementation of Wilhelm Osbahr’s entrepreneur balance sheet theory assumptions – a case study

Directory of Open Access Journals (Sweden)

EWA ŚNIEŻEK , MICHAŁ WIATR

2015-12-01

Full Text Available The aim of this study is to present the possibilities of the practical application of Osbahr’s balance sheet theory assumptions, as one of many possible attempts to close the information gap in the financial reporting of the twenty-first century. Wilhelm Osbahr, at the beginning of the 20th century, made an attempt to solve the problem of indicating the balance sheet values (the impact of balance sheet evaluation on the balance sheet items, from the point of view of an entrepreneur or business owner, at the same time clearly emphasizing the necessity to deal with the balance sheet structure through the prism of the objectives pursued by the company. Osbahr postulated highlighting any changes occurring in the economic structure of the company and its components, which do not result directly from its operating activities, and so to present them in the position called “adjustments”. This article uses the deductive method supported by literature studies and a case study method. The authors using the case study method confirm the possibility of using the described balance sheet theory in the current financial reporting based on actual data of the company ABC Ltd. They also show that a balance sheet which is presented according to the new reporting formula discloses new quality of information for the financial reporting users.

Integration of expression data in genome-scale metabolic network reconstructions

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Anna S. Blazier

2012-08-01

Full Text Available With the advent of high-throughput technologies, the field of systems biology has amassed an abundance of omics data, quantifying thousands of cellular components across a variety of scales, ranging from mRNA transcript levels to metabolite quantities. Methods are needed to not only integrate this omics data but to also use this data to heighten the predictive capabilities of computational models. Several recent studies have successfully demonstrated how flux balance analysis (FBA, a constraint-based modeling approach, can be used to integrate transcriptomic data into genome-scale metabolic network reconstructions to generate predictive computational models. In this review, we summarize such FBA-based methods for integrating expression data into genome-scale metabolic network reconstructions, highlighting their advantages as well as their limitations.

Leucine metabolism in patients with Hepatic Encephalopathy

International Nuclear Information System (INIS)

McGhee, A.S.; Kassouny, M.E.; Matthews, D.E.; Millikan, W.

1986-01-01

A primed continuous infusion of [ 15 N, 1- 13 C]leucine was used to determine whether increased oxidation and/or protein synthesis of leucine occurs in patients with cirrhosis. Five controls and patients were equilibrated on a metabolic balance diet [0.6 g protein per kg ideal body weight (IBW)]. An additional four patients were equilibrated in the same manner with the same type of diet with a protein level of 0.75 g per kg IBW. Plasma leucine and breath CO 2 enrichments were measured by mass spectrometry. Protein synthesis and leucine metabolism were identical in controls and patients when both were fed a diet with 0.6 g protein/kg IBW. Results indicate that systemic derangements of leucine metabolism are not the cause of Hepatic Encephalopathy

Does a mineral wristband affect balance? A randomized, controlled, double-blind study.

Science.gov (United States)

Hansson, Eva Ekvall; Beckman, Anders; Persson, Liselott

2015-06-26

Having good balance is a facilitating factor in the performance of everyday activities. Good balance is also essential in various sport activities in order to both get results and prevent injury. A common measure of balance is postural sway, which can be measured both antero-posteriorly and medio-laterally. There are several companies marketing wristbands whose intended function is to improve balance, strength and flexibility. Randomized controlled trials have shown that wristbands with holograms have no effect on balance but studies on wristbands with minerals seem to be lacking. The aim of this study was to investigate if the mineral wristband had any effect on postural sway in a group of healthy individuals. Randomized, controlled, double-blind study. The study group consisted of 40 healthy persons. Postural sway was measured antero-posteriorly and medio-laterally on a force plate, to compare: the mineral wristband, a placebo wristband, and without any wristband. The measurements were performed for 30 s, in four situations: with open eyes and closed eyes, standing on a firm surface and on foam. Analyses were made with multilevel technique. The use of wristband with or without minerals did not alter postural sway. Closed eyes and standing on foam both prolonged the dependent measurement, irrespective if it was medio-lateral or antero-posterior. Wearing any wristband (mineral or placebo) gave a small (0.22-0.36 mm/s) but not statistically significant reduction of postural sway compared to not wearing wristband. This study showed no effect on postural sway by using the mineral wristband, compared with a placebo wristband or no wristband. Wearing any wristband at all (mineral or placebo) gave a small but not statistically significant reduction in postural sway, probably caused by sensory input.

[Balance trainability using the Nintendo Wii balance board in sportive people].

Science.gov (United States)

Paukowits, S; Stöggl, T

2014-03-01

A multivariable training has a positive impact on balance skills and risk of injury. To date the effect of this training using the Nintendo Wii balance board in sportive people has not yet been investigated. The aim of this study was to investigate whether training with the Nintendo Wii balance board can improve balance skills. 20 people were randomized into a control and an intervention group each with 10 people who performed a unilateral stance test with eyes open and closed as well as the star excursion balance test before and after the intervention. The control group completed their usual sports and the intervention group an adjunct training with the Nintendo Wii balance board for 4 weeks. Adjunct Training using the Nintendo Wii Balance Board did not improve sportive people's balance skills significantly. The intervention group, however, attained better results in the star excursion balance test, whereas the control group did not show any changes. The unilateral stance tests did not provide significant differences before and after training within both groups. The use of the Nintendo Wii balance board should be further investigated by employing individual difficulty levels. © Georg Thieme Verlag KG Stuttgart · New York.

Balance and Self-Efficacy of Balance in Children with CHARGE Syndrome

Science.gov (United States)

Haibach, Pamela S.; Lieberman, Lauren J.

2013-01-01

Introduction: Balance is a critical component of daily living, because it affects all movements and the ability to function independently. Children with CHARGE syndrome have sensory and motor impairments that could negatively affect their balance and postural control. The purpose of the study presented in this article was to assess the balance and…

Metabolic studies in older mentally retarded patients: significance of metabolic testing and correlation with the clinical phenotype.

NARCIS (Netherlands)

Buggenhout, G.J.C.M. van; Trijbels, J.M.F.; Wevers, R.A.; Trommelen, J.C.M.; Hamel, B.C.J.; Brunner, H.G.; Fryns, J.P.

2001-01-01

In 471 adult mentally retarded adult patients (mean age 46 years; 92.6% males) living in an institution for the mentally retarded, a clinical examination, cytogenetic and molecular studies were done. 306 patients were screened for metabolic disorders. In 7 additional patients a metabolic disorder

Population FBA predicts metabolic phenotypes in yeast.

Directory of Open Access Journals (Sweden)

Piyush Labhsetwar

2017-09-01

Full Text Available Using protein counts sampled from single cell proteomics distributions to constrain fluxes through a genome-scale model of metabolism, Population flux balance analysis (Population FBA successfully described metabolic heterogeneity in a population of independent Escherichia coli cells growing in a defined medium. We extend the methodology to account for correlations in protein expression arising from the co-regulation of genes and apply it to study the growth of independent Saccharomyces cerevisiae cells in two different growth media. We find the partitioning of flux between fermentation and respiration predicted by our model agrees with recent 13C fluxomics experiments, and that our model largely recovers the Crabtree effect (the experimentally known bias among certain yeast species toward fermentation with the production of ethanol even in the presence of oxygen, while FBA without proteomics constraints predicts respirative metabolism almost exclusively. The comparisons to the 13C study showed improvement upon inclusion of the correlations and motivated a technique to systematically identify inconsistent kinetic parameters in the literature. The minor secretion fluxes for glycerol and acetate are underestimated by our method, which indicate a need for further refinements to the metabolic model. For yeast cells grown in synthetic defined (SD medium, the calculated broad distribution of growth rates matches experimental observations from single cell studies, and we characterize several metabolic phenotypes within our modeled populations that make use of diverse pathways. Fast growing yeast cells are predicted to perform significant amount of respiration, use serine-glycine cycle and produce ethanol in mitochondria as opposed to slow growing cells. We use a genetic algorithm to determine the proteomics constraints necessary to reproduce the growth rate distributions seen experimentally. We find that a core set of 51 constraints are essential but

The interplay between sulphur and selenium metabolism influences the intracellular redox balance in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Mapelli, Valeria; Hillestrøm, Peter René; Patil, Kalpesh

2012-01-01

oxidative stress response is active when yeast actively metabolizes Se, and this response is linked to the generation of intracellular redox imbalance. The redox imbalance derives from a disproportionate ratio between the reduced and oxidized forms of glutathione and also from the influence of Se metabolism...

Effects of DanceSport on walking balance and standing balance among the elderly.

Science.gov (United States)

Sohn, Jeehoon; Park, Sung-Ha; Kim, Sukwon

2018-05-04

Dancesport is a popular activity among older adults who look for fun and fitness in Korea. Studies reported positive sociological and psychological effects of dancesport. But, little studies were performed to evaluate the effects of dancesport on balance performances. The objective of the present study was to evaluate the effects of dancesport for 15 weeks on walking balance and standing balance of older adults. Older adults regularly participated in the dancesport program 3 times a week for 15 weeks. The program included Rumba, Cha-cha-cha, and Jive. They exercised the prescribed dancesport at intermediate level for 50-60 mins for each time. A total 22 reflective markers were placed on the anatomical landmarks and 8 cameras were used to measure 3-D positions of participants. Also, center of pressure (COP) data were measured to analyze standing balance using a ground reaction board at 1200 Hz for 30 seconds. One-way analysis of variance (ANOVA) was performed to test the effects of 15 weeks of dancesport on walking balance and standing balance. The results suggested that, after 15 weeks of dancesport participation, older adults' walking balance (48.3 ± 20.3 cm2 vs 38.2 ± 18.2 cm2) and standing balance (COP area: 189.4 ± 85.4 mm2 vs 103.5 ± 55.4mm2, COP distance: 84.2 ± 34.4 cm vs 76.5 ± 21.4 cm) were significantly improved. Performing dancesport would require moving center of mass rapidly and frequently while maintaining posture. This may result in improving walking balance and standing balance in the present study. The study concluded that dancesport would be an effective exercise method in enhancing postural stability of older adults.

Red pitaya juice supplementation ameliorates energy balance homeostasis by modulating obesity-related genes in high-carbohydrate, high-fat diet-induced metabolic syndrome rats.

Science.gov (United States)

Ramli, Nurul Shazini; Ismail, Patimah; Rahmat, Asmah

2016-07-26

Red pitaya (Hylocereus polyrhizus) or known as buah naga merah in Malay belongs to the cactus family, Cactaceae. Red pitaya has been shown to give protection against liver damage and may reduce the stiffness of the heart. Besides, the beneficial effects of red pitaya against obesity have been reported; however, the mechanism of this protection is not clear. Therefore, in the present study, we have investigated the red pitaya-targeted genes in obesity using high-carbohydrate, high-fat diet-induced metabolic syndrome rat model. A total of four groups were tested: corn-starch (CS), corn-starch + red pitaya juice (CRP), high-carbohydrate, high-fat (HCHF) and high-carbohydrate, high-fat + red pitaya juice (HRP). The intervention with 5 % red pitaya juice was continued for 8 weeks after 8 weeks initiation of the diet. Retroperitoneal, epididymal and omental fat pads were collected and weighed. Plasma concentration of IL-6 and TNF-α were measured using commercial kits. Gene expression analysis was conducted using RNA extracted from liver samples. A total of eighty-four genes related to obesity were analyzed using PCR array. The rats fed HCHF-diet for 16 weeks increased body weight, developed excess abdominal fat deposition and down-regulated the expression level of IL-1α, IL-1r1, and Cntfr as compared to the control group. Supplementation of red pitaya juice for 8 weeks increased omental and epididymal fat but no change in retroperitoneal fat was observed. Red pitaya juice reversed the changes in energy balance homeostasis in liver tissues by regulation of the expression levels of Pomc and Insr. The increased protein expression levels of IL-6 and TNF-α in HCHF group and red pitaya treated rats confirmed the results of gene expression. Collectively, this study revealed the usefulness of this diet-induced rat model and the beneficial effects of red pitaya on energy balance homeostasis by modulating the anorectic, orexigenic and energy expenditure related

MiR-637 maintains the balance between adipocytes and osteoblasts by directly targeting Osterix.

Science.gov (United States)

Zhang, Jin-fang; Fu, Wei-ming; He, Ming-liang; Wang, Hua; Wang, Wei-mao; Yu, Shi-cang; Bian, Xiu-Wu; Zhou, Jin; Lin, Marie C M; Lu, Gang; Poon, Wai-sang; Kung, Hsiang-fu

2011-11-01

Bone development is dynamically regulated by homeostasis, in which a balance between adipocytes and osteoblasts is maintained. Disruption of this differentiation balance leads to various bone-related metabolic diseases, including osteoporosis. In the present study, a primate-specific microRNA (miR-637) was found to be involved in the differentiation of human mesenchymal stem cells (hMSCs). Our preliminary data indicated that miR-637 suppressed the growth of hMSCs and induced S-phase arrest. Expression of miR-637 was increased during adipocyte differentiation (AD), whereas it was decreased during osteoblast differentiation (OS), which suggests miR-637 could act as a mediator of adipoosteogenic differentiation. Osterix (Osx), a significant transcription factor of osteoblasts, was shown to be a direct target of miR-637, which significantly enhanced AD and suppressed OS in hMSCs through direct suppression of Osx expression. Furthermore, miR-637 also significantly enhanced de novo adipogenesis in nude mice. In conclusion, our data indicated that the expression of miR-637 was indispensable for maintaining the balance of adipocytes and osteoblasts. Disruption of miR-637 expression patterns leads to irreversible damage to the balance of differentiation in bone marrow.

Nitrogen and carbon source balance determines longevity, independently of fermentative or respiratory metabolism in the yeast Saccharomyces cerevisiae.

Science.gov (United States)

Santos, Júlia; Leitão-Correia, Fernanda; Sousa, Maria João; Leão, Cecília

2016-04-26

Dietary regimens have proven to delay aging and age-associated diseases in several eukaryotic model organisms but the input of nutritional balance to longevity regulation is still poorly understood. Here, we present data on the role of single carbon and nitrogen sources and their interplay in yeast longevity. Data demonstrate that ammonium, a rich nitrogen source, decreases chronological life span (CLS) of the prototrophic Saccharomyces cerevisiae strain PYCC 4072 in a concentration-dependent manner and, accordingly, that CLS can be extended through ammonium restriction, even in conditions of initial glucose abundance. We further show that CLS extension depends on initial ammonium and glucose concentrations in the growth medium, as long as other nutrients are not limiting. Glutamine, another rich nitrogen source, induced CLS shortening similarly to ammonium, but this effect was not observed with the poor nitrogen source urea. Ammonium decreased yeast CLS independently of the metabolic process activated during aging, either respiration or fermentation, and induced replication stress inhibiting a proper cell cycle arrest in G0/G1 phase. The present results shade new light on the nutritional equilibrium as a key factor on cell longevity and may contribute for the definition of interventions to promote life span and healthy aging.

Studi Tentang Work Life Balance dan Kepuasan Karir Pekerja Wanita di Jakarta [A Study of Work-Life Balance and Career Satisfaction of Working Women in Jakarta

Directory of Open Access Journals (Sweden)

Sylvia Diana Purba

2015-09-01

Full Text Available This research proposes to find out the influence of availability of career information on career satisfaction of career woman in Jakarta, Participants in this study are 199 women, consist of lecturers, doctors, police women, bank employees, etc. Work-life balance, awareness of organizational plans for self, and match between individual and organizational career plans are used as mediating variables on the impact of availability of career information toward career satisfaction. Research finding shows that work-life balance and awareness of organizational plans have no significant effects as mediating variables on the impact of the availability of career information toward career satisfaction. Meanwhile, the match between individual and organizational career plans have a significant effect as a weak mediating variable. Work-life balance issues seem not to be a concern informing career satisfaction among career women in Indonesia.

Purine Metabolism in Acute Cerebral Ischemia

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Ye. V. Oreshnikov

2008-01-01

Full Text Available Objective: to study the specific features of purine metabolism in clinically significant acute cerebral ischemia. Subjects and materials. Three hundred and fifty patients with the acutest cerebral ischemic stroke were examined. The parameters of gas and electrolyte composition, acid-base balance, the levels of malonic dialdehyde, adenine, guanine, hypox-anthine, xanthine, and uric acid, and the activity of xanthine oxidase were determined in arterial and venous bloods and spinal fluid. Results. In ischemic stroke, hyperuricemia reflects the severity of cerebral metabolic disturbances, hemodynamic instability, hypercoagulation susceptiility, and the extent of neurological deficit. In ischemic stroke, hyperuri-corachia is accompanied by the higher spinal fluid levels of adenine, guanine, hypoxanthine, and xanthine and it is an indirect indicator of respiratory disorders of central genesis, systemic acidosis, hypercoagulation susceptibility, free radical oxidation activation, the intensity of a stressor response to cerebral ischemia, cerebral metabolic disturbances, the depth of reduced consciousness, and the severity of neurological deficit. Conclusion. The high venous blood activity of xanthine oxidase in ischemic stroke is associated with the better neurological parameters in all follow-up periods, the better early functional outcome, and lower mortality rates. Key words: hyperuricemia, stroke, xanthine oxidase, uric acid, cerebral ischemia.

Central Pathways Integrating Metabolism and Reproduction in Teleosts

Science.gov (United States)

Shahjahan, Md.; Kitahashi, Takashi; Parhar, Ishwar S.

2014-01-01

Energy balance plays an important role in the control of reproduction. However, the cellular and molecular mechanisms connecting the two systems are not well understood especially in teleosts. The hypothalamus plays a crucial role in the regulation of both energy balance and reproduction, and contains a number of neuropeptides, including gonadotropin-releasing hormone (GnRH), orexin, neuropeptide-Y, ghrelin, pituitary adenylate cyclase-activating polypeptide, α-melanocyte stimulating hormone, melanin-concentrating hormone, cholecystokinin, 26RFamide, nesfatin, kisspeptin, and gonadotropin-inhibitory hormone. These neuropeptides are involved in the control of energy balance and reproduction either directly or indirectly. On the other hand, synthesis and release of these hypothalamic neuropeptides are regulated by metabolic signals from the gut and the adipose tissue. Furthermore, neurons producing these neuropeptides interact with each other, providing neuronal basis of the link between energy balance and reproduction. This review summarizes the advances made in our understanding of the physiological roles of the hypothalamic neuropeptides in energy balance and reproduction in teleosts, and discusses how they interact with GnRH, kisspeptin, and pituitary gonadotropins to control reproduction in teleosts. PMID:24723910

METs in adults while playing active video games: a metabolic chamber study.

Science.gov (United States)

Miyachi, Motohiko; Yamamoto, Kenta; Ohkawara, Kazunori; Tanaka, Shigeho

2010-06-01

Active video game systems controlled through arm gestures and motions (Nintendo Wii Sports) and video games controlled through force plate (Wii Fit Plus) are becoming increasingly popular. This study was performed to determine the energy expenditure (EE) during Wii Fit Plus and Wii Sports game activities. Twelve adult men and women performed all the activities of Wii Sports (five activities: golf, bowling, tennis, baseball, and boxing) and Wii Fit Plus (63 activities classified as yoga, resistance, balance, and aerobic exercises). Each activity was continued for at least 8 min to obtain a steady-state EE. Because EE was assessed in an open-circuit indirect metabolic chamber consisting of an airtight room (20,000 or 15,000 L), subjects were freed of apparatus to collect expired gas while playing the games. MET value was calculated from resting EE and steady-state EE during activity. The mean MET values of all 68 activities were distributed over a wide range from 1.3 METs (Lotus Focus) to 5.6 METs (single-arm stand). The mean MET values in yoga, balance, resistance, and aerobic exercise of Wii Fit Plus and Wii Sports were 2.1, 2.0, 3.2, 3.4, and 3.0 METs, respectively. Forty-six activities (67%) were classified as light intensity (6.0 METs). Time spent playing one-third of the activities supplied by motion- and gesture-controlled video games can count toward the daily amount of exercise required according to the guidelines provided by the American College of Sports Medicine and the American Heart Association, which focus on 30 min of moderate-intensity daily physical activity 5 d x wk(-1).

A role for central nervous system PPAR-γ in the regulation of energy balance.

Science.gov (United States)

Ryan, Karen K; Li, Bailing; Grayson, Bernadette E; Matter, Emily K; Woods, Stephen C; Seeley, Randy J

2011-05-01

The peroxisome proliferator-activated receptor-γ (PPAR-γ) is a nuclear receptor that is activated by lipids to induce the expression of genes involved in lipid and glucose metabolism, thereby converting nutritional signals into metabolic consequences. PPAR-γ is the target of the thiazolidinedione (TZD) class of insulin-sensitizing drugs, which have been widely prescribed to treat type 2 diabetes mellitus. A common side effect of treatment with TZDs is weight gain. Here we report a previously unknown role for central nervous system (CNS) PPAR-γ in the regulation of energy balance. We found that both acute and chronic activation of CNS PPAR-γ, by either TZDs or hypothalamic overexpression of a fusion protein consisting of PPAR-γ and the viral transcriptional activator VP16 (VP16-PPAR-γ), led to positive energy balance in rats. Blocking the endogenous activation of CNS PPAR-γ with pharmacological antagonists or reducing its expression with shRNA led to negative energy balance, restored leptin sensitivity in high-fat-diet (HFD)-fed rats and blocked the hyperphagic response to oral TZD treatment. These findings have implications for the widespread clinical use of TZD drugs and for understanding the etiology of diet-induced obesity.

Hydrogen production and metabolic flux analysis of metabolically engineered Escherichia coli strains

Energy Technology Data Exchange (ETDEWEB)

Kim, Seohyoung; Seol, Eunhee; Park, Sunghoon [Department of Chemical and Biochemical Engineering, Pusan National University, Busan 609-735 (Korea); Oh, You-Kwan [Bioenergy Research Center, Korea Institute of Energy Research, Daejeon 305-543 (Korea); Wang, G.Y. [Department of Oceanography, University of Hawaii at Manoa Honolulu, HI 96822 (United States)

2009-09-15

Escherichia coli can produce H{sub 2} from glucose via formate hydrogen lyase (FHL). In order to improve the H{sub 2} production rate and yield, metabolically engineered E. coli strains, which included pathway alterations in their H{sub 2} production and central carbon metabolism, were developed and characterized by batch experiments and metabolic flux analysis. Deletion of hycA, a negative regulator for FHL, resulted in twofold increase of FHL activity. Deletion of two uptake hydrogenases (1 (hya) and hydrogenase 2 (hyb)) increased H{sub 2} production yield from 1.20 mol/mol glucose to 1.48 mol/mol glucose. Deletion of lactate dehydrogenase (ldhA) and fumarate reductase (frdAB) further improved the H{sub 2} yield; 1.80 mol/mol glucose under high H{sub 2} pressure or 2.11 mol/mol glucose under reduced H{sub 2} pressure. Several batch experiments at varying concentrations of glucose (2.5-10 g/L) and yeast extract (0.3 or 3.0 g/L) were conducted for the strain containing all these genetic alternations, and their carbon and energy balances were analyzed. The metabolic flux analysis revealed that deletion of ldhA and frdAB directed most of the carbons from glucose to the glycolytic pathway leading to H{sub 2} production by FHL, not to the pentose phosphate pathway. (author)

Adaptive remodeling of skeletal muscle energy metabolism in high-altitude hypoxia: Lessons from AltitudeOmics.

Science.gov (United States)

Chicco, Adam J; Le, Catherine H; Gnaiger, Erich; Dreyer, Hans C; Muyskens, Jonathan B; D'Alessandro, Angelo; Nemkov, Travis; Hocker, Austin D; Prenni, Jessica E; Wolfe, Lisa M; Sindt, Nathan M; Lovering, Andrew T; Subudhi, Andrew W; Roach, Robert C

2018-05-04

Metabolic responses to hypoxia play important roles in cell survival strategies and disease pathogenesis in humans. However, the homeostatic adjustments that balance changes in energy supply and demand to maintain organismal function under chronic low oxygen conditions remain incompletely understood, making it difficult to distinguish adaptive from maladaptive responses in hypoxia-related pathologies. We integrated metabolomic and proteomic profiling with mitochondrial respirometry and blood gas analyses to comprehensively define the physiological responses of skeletal muscle energy metabolism to 16 days of high-altitude hypoxia (5260 m) in healthy volunteers from the AltitudeOmics project. In contrast to the view that hypoxia down-regulates aerobic metabolism, results show that mitochondria play a central role in muscle hypoxia adaptation by supporting higher resting phosphorylation potential and enhancing the efficiency of long-chain acylcarnitine oxidation. This directs increases in muscle glucose toward pentose phosphate and one-carbon metabolism pathways that support cytosolic redox balance and help mitigate the effects of increased protein and purine nucleotide catabolism in hypoxia. Muscle accumulation of free amino acids favor these adjustments by coordinating cytosolic and mitochondrial pathways to rid the cell of excess nitrogen, but might ultimately limit muscle oxidative capacity in vivo Collectively, these studies illustrate how an integration of aerobic and anaerobic metabolism is required for physiological hypoxia adaptation in skeletal muscle, and highlight protein catabolism and allosteric regulation as unexpected orchestrators of metabolic remodeling in this context. These findings have important implications for the management of hypoxia-related diseases and other conditions associated with chronic catabolic stress. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Military training elicits marked increases in plasma metabolomic signatures of energy metabolism, lipolysis, fatty acid oxidation, and ketogenesis.

Science.gov (United States)

Karl, J Philip; Margolis, Lee M; Murphy, Nancy E; Carrigan, Christopher T; Castellani, John W; Madslien, Elisabeth H; Teien, Hilde-Kristin; Martini, Svein; Montain, Scott J; Pasiakos, Stefan M

2017-09-01

Military training studies provide unique insight into metabolic responses to extreme physiologic stress induced by multiple stressor environments, and the impacts of nutrition in mediating these responses. Advances in metabolomics have provided new approaches for extending current understanding of factors modulating dynamic metabolic responses in these environments. In this study, whole-body metabolic responses to strenuous military training were explored in relation to energy balance and macronutrient intake by performing nontargeted global metabolite profiling on plasma collected from 25 male soldiers before and after completing a 4-day, 51-km cross-country ski march that produced high total daily energy expenditures (25.4 MJ/day [SD 2.3]) and severe energy deficits (13.6 MJ/day [SD 2.5]). Of 737 identified metabolites, 478 changed during the training. Increases in 88% of the free fatty acids and 91% of the acylcarnitines, and decreases in 88% of the mono- and diacylglycerols detected within lipid metabolism pathways were observed. Smaller increases in 75% of the tricarboxylic acid cycle intermediates, and 50% of the branched-chain amino acid metabolites detected were also observed. Changes in multiple metabolites related to lipid metabolism were correlated with body mass loss and energy balance, but not with energy and macronutrient intakes or energy expenditure. These findings are consistent with an increase in energy metabolism, lipolysis, fatty acid oxidation, ketogenesis, and branched-chain amino acid catabolism during strenuous military training. The magnitude of the energy deficit induced by undereating relative to high energy expenditure, rather than macronutrient intake, appeared to drive these changes, particularly within lipid metabolism pathways. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

A Case Study and Balance Sheet Approach to Unemployment.

Science.gov (United States)

Hesketh, Beryl; And Others

1987-01-01

Describes positive and negative aspects of employment and unemployment in a balance sheet framework. Discusses the value of the balance sheet approach in understanding individual differences in reactions to unemployment. (Author/KS)

Nitrogen metabolism in the tissues of the ruminant

International Nuclear Information System (INIS)

Buttery, P.J.

1986-01-01

Protein metabolism in animals is in a constant state of flux, the processes of protein synthesis and protein breakdown acting against each other, and the balance between the two processes causing changes in the mass of protein in a tissue. Reduction in the diet reduces both protein synthesis and protein degradation unless the dietary depletion is severe and prolonged, when there is a marked increase in protein catabolism. The synthesis and degradation of protein can be manipulated by anabolic agents, thus increasing the efficiency of animals. While the use of these agents has met with success in many countries, it remains to be seen whether they will be useful in harsh environments. Lactation and pregnancy put an extra demand on the nitrogen economy of animals. Evidence indicates that the extra amino acids needed for milk production do not come from muscle protein breakdown. Many animals in harsh environments are infected with parasites; intestinal parasites reduce food intake and cause blood loss into the intestines. Associated with this is a general disruption of protein metabolism. In all these studies, isotopic techniques have played a vital role. Few studies have been conducted on nitrogen metabolism in the tissue of ruminants exposed to harsh environments (with one notable exception: rumen function studies, some of which are described elsewhere in the Proceedings of this Seminar). This lack of work on nitrogen metabolism of animals from the harsher environments has often made it necessary to extrapolate data obtained from animals found and maintained in the temperate zones to quite different environments and to animals maintained on quite different dietary regimens. Several examples of the use of isotopes in metabolic studies with animals to yield information of direct or potential relevance to the harsh environments are presented. (author)

NAD+ metabolism and the control of energy homeostasis - a balancing act between mitochondria and the nucleus

Science.gov (United States)

Cantó, Carles; Menzies, Keir; Auwerx, Johan

2015-01-01

NAD+ has emerged as a vital cofactor that can rewire metabolism, activate sirtuins and maintain mitochondrial fitness through mechanisms such as the mitochondrial unfolded protein response. This improved understanding of NAD+ metabolism revived interest in NAD+ boosting strategies to manage a wide spectrum of diseases, ranging from diabetes to cancer. In this review, we summarize how NAD+ metabolism links energy status with adaptive cellular and organismal responses and how this knowledge can be therapeutically exploited. PMID:26118927

Neck pain and postural balance among workers with high postural demands - a cross-sectional study

DEFF Research Database (Denmark)

Jørgensen, Marie B.; Skotte, Jørgen H.; Holtermann, Andreas

2011-01-01

Neck pain is related to impaired postural balance among patients and is highly prevalent among workers with high postural demands, for example, cleaners. We therefore hypothesised, that cleaners with neck pain suffer from postural dysfunction. This cross-sectional study tested if cleaners with neck...... pain have an impaired postural balance compared with cleaners without neck pain. Postural balance of 194 cleaners with (n = 85) and without (N = 109) neck pain was studied using three different tests. Success or failure to maintain the standing position for 30 s in unilateral stance was recorded...... to cleaners without neck/low back pain (p balance, measured as CEA (p

Effects of photoperiod on energy metabolism and thermogenesis in ...

African Journals Online (AJOL)

The plasticity in energy intake, basal metabolic rate (BMR) and nonshivering thermogenesis (NST) was very important for the regulations in energy balance and thermogenesis in Melano-bellied oriental vole exposed to different photoperiod. Change in brown adipose tissue (BAT) cytochrome c oxidase (COX) activity and ...

Effects of dietary bread crust Maillard reaction products on calcium and bone metabolism in rats.

Science.gov (United States)

Roncero-Ramos, Irene; Delgado-Andrade, Cristina; Haro, Ana; Ruiz-Roca, Beatriz; Morales, Francisco J; Navarro, María Pilar

2013-06-01

Maillard reaction products (MRP) consumption has been related with the development of bone degenerative disorders, probably linked to changes in calcium metabolism. We aimed to investigate the effects of MRP intake from bread crust on calcium balance and its distribution, and bone metabolism. During 88 days, rats were fed control diet or diets containing bread crust as source of MRP, or its soluble high molecular weight, soluble low molecular weight or insoluble fractions (bread crust, HMW, LMW and insoluble diets, respectively). In the final week, a calcium balance was performed, then animals were sacrified and some organs removed to analyse calcium levels. A second balance was carried out throughout the experimental period to calculate global calcium retention. Biochemical parameters and bone metabolism markers were measured in serum or urine. Global calcium bioavailability was unmodified by consumption of bread crust or its isolate fractions, corroborating the previously described low affinity of MRP to bind calcium. Despite this, a higher calcium concentration was found in femur due to smaller bones having a lower relative density. The isolate consumption of the fractions altered some bone markers, reflecting a situation of increased bone resorption or higher turnover; this did not take place in the animals fed the bread crust diet. Thus, the bread crust intake does not affect negatively calcium bioavailability and bone metabolism.

Effect of Balance, Strength, and Combined Training on the Balance of the Elderly Women

Directory of Open Access Journals (Sweden)

Alireza Farsi

2015-10-01

Full Text Available Objectives: Ageing is associated with a number of physiologic and functional declines that can increase disability, frailty, and falls in the elderly. Therefore, the purpose of the present study was to study and compare the effect of balance, strength, and combined trainings on the balance (overall, anterior-posterior, medial-lateral of the elderly women. Methods & Materials: Twenty-four older female adults (without history of any injuries in their lower limbs were participated voluntarily in this study and randomly assigned into 3 groups: balance (n=8, strength (n=8 and combined (n=8. A 6-week exercise program was performed at Shahid Beheshti University. The program was performed 3 days per week. Before and after implementation of exercise program, the balance status of the subjects was measured by Biodex stability system. The data were analyzed using 2-way analysis of variance (group×time ANOVA with repeated measures on time, paired–sample t-test, 1–way ANOVA, and Bonferroni post–hoc test (P≤0.005. Results: At the end of training programs, significant improvements were observed between the balance and combined groups with regard to the indexes of overall, anterior–posterior, and medial–lateral balance. Also, the strength group showed a significant growth in the indexes of anterior-posterior and medial-lateral compared to the beginning of the study. There was a significant difference between the balance (P=0.0001 and combined groups (P=0.001 with the strength group with regard to the index of overall balance. Also, there was a significant difference between balance group (P=0.0001 and the combined group (P=0.0001 regarding the anterior-posterior balance. But there were no significant differences between groups with regard to the medial-lateral balance. Conclusion: The study showed that perturbation–based balance training and combined training had the better effects compared to the strength training.

A study on the carotid artery ultrasonography for the metabolic syndrome

International Nuclear Information System (INIS)

Kong, Hye Jung; Cho, Pyong Kon; Kang, Young Han

2013-01-01

The primary goal of this study was to ascertain the primary factors to the affect for the carotid artery intima-media thickness (IMT), the prevalence of metabolic syndrome and other risks can possibly influence the carotid artery IMT. All patients data (total specimens: 289, male: 197, female: 92) including the carotid artery ultrasonography examination. The all data were analyzed by the use of SPSS software, version 21.0 (SPSS, Chicago, IL USA), with the descriptive statistics method. The Results of this study was found to be highly increased in the males than the females. The prevalence of metabolic syndrome in all of the participants was 30.5 percentages. The carotid artery IMT in the subjects with metabolic syndrome was significantly high in both genders, compared to the rest, who were without metabolic syndrome. The Pearsons correlation coefficient of metabolic syndrome and CIMT was 0.378(p<0.01). In conclusions, the present study also supports the association between the carotid artery IMT and the metabolic syndromes with cardiovascular risk factors. Usage of B-mode ultrasonography to measure the carotid artery IMT was found to be highly effective in the current analysis

A study on the carotid artery ultrasonography for the metabolic syndrome

Energy Technology Data Exchange (ETDEWEB)

Kong, Hye Jung; Cho, Pyong Kon [Dept. of Radiological Science, Catholic University of Daegu, Daegu (Korea, Republic of); Kang, Young Han [Dept. of Radiology, Catholic University Hospital of Daegu, Daegu (Korea, Republic of)

2013-09-15

The primary goal of this study was to ascertain the primary factors to the affect for the carotid artery intima-media thickness (IMT), the prevalence of metabolic syndrome and other risks can possibly influence the carotid artery IMT. All patients data (total specimens: 289, male: 197, female: 92) including the carotid artery ultrasonography examination. The all data were analyzed by the use of SPSS software, version 21.0 (SPSS, Chicago, IL USA), with the descriptive statistics method. The Results of this study was found to be highly increased in the males than the females. The prevalence of metabolic syndrome in all of the participants was 30.5 percentages. The carotid artery IMT in the subjects with metabolic syndrome was significantly high in both genders, compared to the rest, who were without metabolic syndrome. The Pearsons correlation coefficient of metabolic syndrome and CIMT was 0.378(p<0.01). In conclusions, the present study also supports the association between the carotid artery IMT and the metabolic syndromes with cardiovascular risk factors. Usage of B-mode ultrasonography to measure the carotid artery IMT was found to be highly effective in the current analysis.

Flipping the Metabolic Switch: Understanding and Applying the Health Benefits of Fasting.

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Anton, Stephen D; Moehl, Keelin; Donahoo, William T; Marosi, Krisztina; Lee, Stephanie A; Mainous, Arch G; Leeuwenburgh, Christiaan; Mattson, Mark P

2018-02-01

Intermittent fasting (IF) is a term used to describe a variety of eating patterns in which no or few calories are consumed for time periods that can range from 12 hours to several days, on a recurring basis. This review is focused on the physiological responses of major organ systems, including the musculoskeletal system, to the onset of the metabolic switch: the point of negative energy balance at which liver glycogen stores are depleted and fatty acids are mobilized (typically beyond 12 hours after cessation of food intake). Emerging findings suggest that the metabolic switch from glucose to fatty acid-derived ketones represents an evolutionarily conserved trigger point that shifts metabolism from lipid/cholesterol synthesis and fat storage to mobilization of fat through fatty acid oxidation and fatty acid-derived ketones, which serve to preserve muscle mass and function. Thus, IF regimens that induce the metabolic switch have the potential to improve body composition in overweight individuals. Moreover, IF regimens also induce the coordinated activation of signaling pathways that optimize physiological function, enhance performance, and slow aging and disease processes. Future randomized controlled IF trials should use biomarkers of the metabolic switch (e.g., plasma ketone levels) as a measure of compliance and of the magnitude of negative energy balance during the fasting period. © 2017 The Obesity Society.

Balance ability and athletic performance.

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Hrysomallis, Con

2011-03-01

The relationship between balance ability and sport injury risk has been established in many cases, but the relationship between balance ability and athletic performance is less clear. This review compares the balance ability of athletes from different sports, determines if there is a difference in balance ability of athletes at different levels of competition within the same sport, determines the relationship of balance ability with performance measures and examines the influence of balance training on sport performance or motor skills. Based on the available data from cross-sectional studies, gymnasts tended to have the best balance ability, followed by soccer players, swimmers, active control subjects and then basketball players. Surprisingly, no studies were found that compared the balance ability of rifle shooters with other athletes. There were some sports, such as rifle shooting, soccer and golf, where elite athletes were found to have superior balance ability compared with their less proficient counterparts, but this was not found to be the case for alpine skiing, surfing and judo. Balance ability was shown to be significantly related to rifle shooting accuracy, archery shooting accuracy, ice hockey maximum skating speed and simulated luge start speed, but not for baseball pitching accuracy or snowboarding ranking points. Prospective studies have shown that the addition of a balance training component to the activities of recreationally active subjects or physical education students has resulted in improvements in vertical jump, agility, shuttle run and downhill slalom skiing. A proposed mechanism for the enhancement in motor skills from balance training is an increase in the rate of force development. There are limited data on the influence of balance training on motor skills of elite athletes. When the effectiveness of balance training was compared with resistance training, it was found that resistance training produced superior performance results for

Management of metabolic syndrome through probiotic and prebiotic interventions

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Rashmi H Mallappa

2012-01-01

Full Text Available Metabolic syndrome is a complex disorder caused by a cluster of interrelated factors that increases the risk of cardiovascular diseases and type 2 diabetes. Obesity is the main precursor for metabolic syndrome that can be targeted in developing various therapies. With this view, several physical, psychological, pharmaceutical and dietary therapies have been proposed for the management of obesity. However, dietary strategies found more appropriate without any adverse health effects. Application of probiotics and prebiotics as biotherapeutics is the new emerging area in developing dietary strategies and many people are interested in learning the facts behind these health claims. Recent studies established the role of probiotics and prebiotics in weight management with possible mechanisms of improved microbial balance, decreased food intake, decreased abdominal adiposity and increased mucosal integrity with decreased inflammatory tone. Hence, the above "Pharmaco-nutritional" approach has been selected and extensively reviewed to gain thorough knowledge on putative mechanisms of probiotic and prebiotic action in order to develop dietary strategies for the management of metabolic syndrome.

Balance evaluation in haemophilic preadolescent patients using Nintendo Wii Balance Board®.

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Pérez-Alenda, S; Carrasco, J J; Aguilar-Rodríguez, M; Martínez-Gómez, L; Querol-Giner, M; Cuesta-Barriuso, R; Torres-Ortuño, A; Querol, F

2017-01-01

Alterations in the musculoskeletal system, especially in the lower limbs, limit physical activity and affect balance and walking. Postural impairments in haemophilic preteens could increase the risk of bleeding events and deteriorate the physical condition, promoting the progression of haemophilic arthropathy. This study aims to evaluate static postural balance in haemophilic children, assessed by means of the Wii Balance Board ® (WBB). Nineteen children with haemophilia and 19 without haemophilia aged 9-10 years, have participated in this study. Postural balance was assessed by performing four tests, each one lasting 15 s: bipodal eyes open (BEO), bipodal eyes closed (BEC), monopodal dominant leg (MD) and monopodal non-dominant leg (MND). Two balance indices, standard deviation of amplitude (SDA) and standard deviation of velocity (SDV) were calculated in the anterior-posterior (AP) and medial-lateral (ML) directions. Index values were higher in haemophilic group and the differences were statistically significant (P balance in the haemophilic cohort compared to the control group. Accordingly, physiotherapy programmes, physical activity and sports should be designed to improve the postural balance with the aim of preventing joint deterioration and improving quality of life. © 2016 John Wiley & Sons Ltd.

A mathematical framework for yield (vs. rate) optimization in constraint-based modeling and applications in metabolic engineering.

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Klamt, Steffen; Müller, Stefan; Regensburger, Georg; Zanghellini, Jürgen

2018-02-07

The optimization of metabolic rates (as linear objective functions) represents the methodical core of flux-balance analysis techniques which have become a standard tool for the study of genome-scale metabolic models. Besides (growth and synthesis) rates, metabolic yields are key parameters for the characterization of biochemical transformation processes, especially in the context of biotechnological applications. However, yields are ratios of rates, and hence the optimization of yields (as nonlinear objective functions) under arbitrary linear constraints is not possible with current flux-balance analysis techniques. Despite the fundamental importance of yields in constraint-based modeling, a comprehensive mathematical framework for yield optimization is still missing. We present a mathematical theory that allows one to systematically compute and analyze yield-optimal solutions of metabolic models under arbitrary linear constraints. In particular, we formulate yield optimization as a linear-fractional program. For practical computations, we transform the linear-fractional yield optimization problem to a (higher-dimensional) linear problem. Its solutions determine the solutions of the original problem and can be used to predict yield-optimal flux distributions in genome-scale metabolic models. For the theoretical analysis, we consider the linear-fractional problem directly. Most importantly, we show that the yield-optimal solution set (like the rate-optimal solution set) is determined by (yield-optimal) elementary flux vectors of the underlying metabolic model. However, yield- and rate-optimal solutions may differ from each other, and hence optimal (biomass or product) yields are not necessarily obtained at solutions with optimal (growth or synthesis) rates. Moreover, we discuss phase planes/production envelopes and yield spaces, in particular, we prove that yield spaces are convex and provide algorithms for their computation. We illustrate our findings by a small

The Microbiological Memory, an Epigenetic Regulator Governing the Balance Between Good Health and Metabolic Disorders

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Christian A. Devaux

2018-06-01

Full Text Available If the transmission of biological information from one generation to the next is based on DNA, most heritable phenotypic traits such as chronic metabolic diseases, are not linked to genetic variation in DNA sequences. Non-genetic heritability might have several causes including epigenetic, parental effect, adaptive social learning, and influence of the ecological environment. Distinguishing among these causes is crucial to resolve major phenotypic enigmas. Strong evidence indicates that changes in DNA expression through various epigenetic mechanisms can be linked to parent-offspring resemblance in terms of sensitivity to metabolic diseases. Among non-genetic heritable traits, early nutrition could account for a long term deviant programming of genes expression responsible for metabolic diseases in adulthood. Nutrition could shape an inadequate gut microbiota (dysbiosis, triggering epigenetic deregulation of transcription which can be observed in chronic metabolic diseases. We review herein the evidence that dysbiosis might be a major cause of heritable epigenetic patterns found to be associated with metabolic diseases. By taking into account the recent advances on the gut microbiome, we have aggregated together different observations supporting the hypothesis that the gut microbiota could promote the molecular crosstalk between bacteria and surrounding host cells which controls the pathological epigenetic signature. We introduce for the first time the concept of “microbiological memory” as the main regulator of the epigenetic signatures, thereby indicating that different causes of non-genetic heritability can interact in complex pathways to produce inheritance.

Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

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Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

2012-01-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

Activating transcription factor 3 regulates immune and metabolic homeostasis.

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Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

2012-10-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

Associations of exercise, sedentary time and insomnia with metabolic syndrome in Taiwanese older adults: A 1-year follow-up study.

Science.gov (United States)

Chen, Li-Jung; Lai, Yun-Ju; Sun, Wen-Jung; Fox, Kenneth R; Chu, Dachen; Ku, Po-Wen

2015-01-01

Understanding the risk factors of metabolic syndrome (MetS) is important to public health, since individuals with MetS have an increased risk of health problems. This study examined the associations of exercise, sedentary time and insomnia with incident MetS among older adults 1 year later. A total of 1,359 older adults receiving hospital health examinations in 2012 were studied, and 779 subjects had a follow-up after 1 year. The components of MetS (waist, blood pressure, high-density lipoprotein cholesterol, fasting glucose and triglyceride) were defined by the Program's Adult Treatment Panel III report. Exercise, sedentary time and insomnia data were obtained through self-report questionnaires. Physical fitness (body fatness, balance and hand grip strength) was measured. Two logistic regressions were computed to examine the associations of exercise/physical fitness, sedentary time and insomnia at baseline with incident MetS 1 year later. The first regression included age, sex, smoking and alcohol as covariates. The second regression was further adjusted with the components of MetS. Sex, exercise/balance, sedentary time and insomnia were significant predictors of MetS. The risk of MetS incidence was 3.36 (95% CI 1.96-5.77) for women, 1.92 (95% CI 1.01-3.63) for those who did not exercise, 2.52 (95% CI 1.37-4.63) for those who sat more than 5 h/day, and 2.17 (95% CI 1.13-4.15) for those with insomnia. Poor balance was significantly associated with greater risk of MetS (AOR = 1.07, 95% CI 1.02-1.12). Sex, sedentary time, insomnia and balance remained significant after adjusting with the components of MetS. Cultivating exercise habits, reducing sedentary time and improving sleep quality may be important strategies for MetS prevention among older adults.

Metabolic modelling of polyhydroxyalkanoate copolymers production by mixed microbial cultures

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Reis Maria AM

2008-07-01

Full Text Available Abstract Background This paper presents a metabolic model describing the production of polyhydroxyalkanoate (PHA copolymers in mixed microbial cultures, using mixtures of acetic and propionic acid as carbon source material. Material and energetic balances were established on the basis of previously elucidated metabolic pathways. Equations were derived for the theoretical yields for cell growth and PHA production on mixtures of acetic and propionic acid as functions of the oxidative phosphorylation efficiency, P/O ratio. The oxidative phosphorylation efficiency was estimated from rate measurements, which in turn allowed the estimation of the theoretical yield coefficients. Results The model was validated with experimental data collected in a sequencing batch reactor (SBR operated under varying feeding conditions: feeding of acetic and propionic acid separately (control experiments, and the feeding of acetic and propionic acid simultaneously. Two different feast and famine culture enrichment strategies were studied: (i either with acetate or (ii with propionate as carbon source material. Metabolic flux analysis (MFA was performed for the different feeding conditions and culture enrichment strategies. Flux balance analysis (FBA was used to calculate optimal feeding scenarios for high quality PHA polymers production, where it was found that a suitable polymer would be obtained when acetate is fed in excess and the feeding rate of propionate is limited to ~0.17 C-mol/(C-mol.h. The results were compared with published pure culture metabolic studies. Conclusion Acetate was more conducive toward the enrichment of a microbial culture with higher PHA storage fluxes and yields as compared to propionate. The P/O ratio was not only influenced by the selected microbial culture, but also by the carbon substrate fed to each culture, where higher P/O ratio values were consistently observed for acetate than propionate. MFA studies suggest that when mixtures of

Metabolic studies of oxyguno in horses

International Nuclear Information System (INIS)

Wong, April S.Y.; Ho, Emmie N.M.; Wan, Terence S.M.; Lam, Kenneth K.H.; Stewart, Brian D.

2015-01-01

Oxyguno (4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione) is a synthetic oral anabolic androgenic steroid commercially available without a prescription. Manufacturers of oxyguno claim that its anabolic effect in metabolic enhancement exceeds that of the classic anabolic steroid testosterone by seven times, but its androgenic side-effects are only twelve percent of testosterone. Like other anabolic androgenic steroids, oxyguno is prohibited in equine sports. The metabolism of oxyguno in either human or horse has not been reported and therefore little is known about its metabolic fate. This paper describes the in vitro and in vivo metabolic studies of oxyguno in racehorses with an objective to identify the most appropriate target metabolites for detecting oxyguno administration. In vitro studies of oxyguno were performed using horse liver microsomes. Metabolites in the incubation mixtures were isolated by liquid–liquid extraction and analysed by gas chromatography-mass spectrometry in the EI mode after trimethylsilylation. In vitro metabolites identified include the stereoisomers of 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β-diol (M1a & M1b); 20-hydroxy-oxyguno (M2); and 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β,20-triol (M3). These novel metabolites were resulted from hydroxylation at C20, and/or reduction of the keto group at C11. For the in vivo studies, two geldings were each administered orally with a total dose of 210 mg oxyguno (52.5 mg twice daily for 2 days). Pre- and post-administration urine and blood samples were collected for analysis. The parent drug oxyguno was detected in both urine and blood, while numerous novel metabolites were detected in urine. The stereoisomers (M1a & M1b) observed in the in vitro studies were also detected in post-administration urine samples. Three other metabolites (M4 - M6) were detected. M4, 4-chloro-17α-methyl-androstane-11-keto-3,17β-diol, was resulted from reductions of the olefin

Metabolic studies of oxyguno in horses

Energy Technology Data Exchange (ETDEWEB)

Wong, April S.Y., E-mail: april.sy.wong-rl@hkjc.org.hk [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Ho, Emmie N.M. [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Wan, Terence S.M., E-mail: terence.sm.wan@hkjc.org.hk [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Lam, Kenneth K.H.; Stewart, Brian D. [Veterinary Regulation & International Liaison, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T, Hong Kong (China)

2015-09-03

Oxyguno (4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione) is a synthetic oral anabolic androgenic steroid commercially available without a prescription. Manufacturers of oxyguno claim that its anabolic effect in metabolic enhancement exceeds that of the classic anabolic steroid testosterone by seven times, but its androgenic side-effects are only twelve percent of testosterone. Like other anabolic androgenic steroids, oxyguno is prohibited in equine sports. The metabolism of oxyguno in either human or horse has not been reported and therefore little is known about its metabolic fate. This paper describes the in vitro and in vivo metabolic studies of oxyguno in racehorses with an objective to identify the most appropriate target metabolites for detecting oxyguno administration. In vitro studies of oxyguno were performed using horse liver microsomes. Metabolites in the incubation mixtures were isolated by liquid–liquid extraction and analysed by gas chromatography-mass spectrometry in the EI mode after trimethylsilylation. In vitro metabolites identified include the stereoisomers of 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β-diol (M1a & M1b); 20-hydroxy-oxyguno (M2); and 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β,20-triol (M3). These novel metabolites were resulted from hydroxylation at C20, and/or reduction of the keto group at C11. For the in vivo studies, two geldings were each administered orally with a total dose of 210 mg oxyguno (52.5 mg twice daily for 2 days). Pre- and post-administration urine and blood samples were collected for analysis. The parent drug oxyguno was detected in both urine and blood, while numerous novel metabolites were detected in urine. The stereoisomers (M1a & M1b) observed in the in vitro studies were also detected in post-administration urine samples. Three other metabolites (M4 - M6) were detected. M4, 4-chloro-17α-methyl-androstane-11-keto-3,17β-diol, was resulted from reductions of the olefin

Metabolic flux analysis of heterotrophic growth in Chlamydomonas reinhardtii.

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Nanette R Boyle

Full Text Available Despite the wealth of knowledge available for C. reinhardtii, the central metabolic fluxes of growth on acetate have not yet been determined. In this study, 13C-metabolic flux analysis (13C-MFA was used to determine and quantify the metabolic pathways of primary metabolism in C. reinhardtii cells grown under heterotrophic conditions with acetate as the sole carbon source. Isotopic labeling patterns of compartment specific biomass derived metabolites were used to calculate the fluxes. It was found that acetate is ligated with coenzyme A in the three subcellular compartments (cytosol, mitochondria and plastid included in the model. Two citrate synthases were found to potentially be involved in acetyl-coA metabolism; one localized in the mitochondria and the other acting outside the mitochondria. Labeling patterns demonstrate that Acetyl-coA synthesized in the plastid is directly incorporated in synthesis of fatty acids. Despite having a complete TCA cycle in the mitochondria, it was also found that a majority of the malate flux is shuttled to the cytosol and plastid where it is converted to oxaloacetate providing reducing equivalents to these compartments. When compared to predictions by flux balance analysis, fluxes measured with 13C-MFA were found to be suboptimal with respect to biomass yield; C. reinhardtii sacrifices biomass yield to produce ATP and reducing equivalents.

Effect of Selected Balance Exercises on the Dynamic Balance of Children with Visual Impairments

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Jazi, Shirin Davarpanah; Purrajabi, Fatemeh; Movahedi, Ahmadreza; Jalali, Shahin

2012-01-01

Introduction: Maintaining balance while walking is of utmost importance for individuals with visual impairments because deficits in dynamic balance have been associated with a high risk of falling. Thus, the primary aim of the study presented here was to determine whether balance training effects the dynamic balance of children with visual…

Glucose regulates hypothalamic long-chain fatty acid metabolism via AMP-activated kinase (AMPK) in neurons and astrocytes.

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Taïb, Bouchra; Bouyakdan, Khalil; Hryhorczuk, Cécile; Rodaros, Demetra; Fulton, Stephanie; Alquier, Thierry

2013-12-27

Hypothalamic controls of energy balance rely on the detection of circulating nutrients such as glucose and long-chain fatty acids (LCFA) by the mediobasal hypothalamus (MBH). LCFA metabolism in the MBH plays a key role in the control of food intake and glucose homeostasis, yet it is not known if glucose regulates LCFA oxidation and esterification in the MBH and, if so, which hypothalamic cell type(s) and intracellular signaling mechanisms are involved. The aim of this study was to determine the impact of glucose on LCFA metabolism, assess the role of AMP-activated Kinase (AMPK), and to establish if changes in LCFA metabolism and its regulation by glucose vary as a function of the kind of LCFA, cell type, and brain region. We show that glucose inhibits palmitate oxidation via AMPK in hypothalamic neuronal cell lines, primary hypothalamic astrocyte cultures, and MBH slices ex vivo but not in cortical astrocytes and slice preparations. In contrast, oleate oxidation was not affected by glucose or AMPK inhibition in MBH slices. In addition, our results show that glucose increases palmitate, but not oleate, esterification into neutral lipids in neurons and MBH slices but not in hypothalamic astrocytes. These findings reveal for the first time the metabolic fate of different LCFA in the MBH, demonstrate AMPK-dependent glucose regulation of LCFA oxidation in both astrocytes and neurons, and establish metabolic coupling of glucose and LCFA as a distinguishing feature of hypothalamic nuclei critical for the control of energy balance.

Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

OpenAIRE

Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

2013-01-01

Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited...

The influence of broiler activity, growth rate, and litter on carbon dioxide balances for the determination of ventilation flow rates in broiler production.

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Calvet, S; Estellés, F; Cambra-López, M; Torres, A G; Van den Weghe, H F A

2011-11-01

Carbon dioxide balances are useful in determining ventilation rates in livestock buildings. These balances need an accurate estimation of the CO(2) produced by animals and their litter to determine the ventilation flows. To estimate the daily variation in ventilation flow, it is necessary to precisely know the daily variation pattern of CO(2) production, which mainly depends on animal activity. The objective of this study was to explore the applicability of CO(2) balances for determining ventilation flows in broiler buildings. More specifically, this work aimed to quantify the amount of CO(2) produced by the litter, as well as the amount of CO(2) produced by the broilers, as a function of productive parameters, and to analyze the influence of broiler activity on CO(2) emissions. Gas concentrations and ventilation flows were simultaneously measured in 3 trials, with 1 under experimental conditions and the other 2 in a commercial broiler farm. In the experimental assay, broiler activity was also determined. At the end of the experimental trial, on the day after the removal of the broilers, the litter accounted for 20% of the total CO(2) produced, and the broilers produced 3.71 L/h of CO(2) per kg of metabolic weight. On the commercial farm, CO(2) production was the same for the 2 cycles (2.60 L/h per kg of metabolic weight, P > 0.05). However, substantial differences were found between CO(2) and broiler activity patterns after changes in light status. A regression model was used to explain these differences (R(2) = 0.52). Carbon dioxide increased with bird activity, being on average 3.02 L/h per kg of metabolic weight for inactive birds and 4.73 L/h per kg of metabolic weight when bird activity was highest. Overall, CO(2) balances are robust tools for determining the daily average ventilation flows in broiler farms. These balances could also be applied at more frequent intervals, but in this case, particular care is necessary after light status changes because of

Manipulating the circadian and sleep cycles to protect against metabolic disease

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Kazunari eNohara

2015-03-01

Full Text Available Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g. obesity involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude enhancing small molecules (CEMs identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep and metabolism will also have far-reaching implications for various chronic human diseases and aging.

Manipulating the circadian and sleep cycles to protect against metabolic disease.

Science.gov (United States)

Nohara, Kazunari; Yoo, Seung-Hee; Chen, Zheng Jake

2015-01-01

Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock, and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g., obesity) involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude-enhancing small molecules (CEMs) identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep, and metabolism will also have far-reaching implications for various chronic human diseases and aging.

Balance Assessment Practices and Use of Standardized Balance Measures Among Ontario Physical Therapists

Science.gov (United States)

Sibley, Kathryn M.; Straus, Sharon E.; Inness, Elizabeth L.; Salbach, Nancy M.

2011-01-01

Background Balance impairment is a significant problem for older adults, as it can influence daily functioning. Treating balance impairment in this population is a major focus of physical therapist practice. Objective The purpose of this study was to document current practices in clinical balance assessment and compare components of balance assessed and measures used across practice areas among physical therapists. Design This was a cross-sectional study. Methods A survey questionnaire was mailed to 1,000 practicing physical therapists in Ontario, Canada. Results Three hundred sixty-nine individuals completed the survey questionnaire. More than 80% of respondents reported that they regularly (more than 60% of the time) assessed postural alignment, static and dynamic stability, functional balance, and underlying motor systems. Underlying sensory systems, cognitive contributions to balance, and reactive control were regularly assessed by 59.6%, 55.0%, and 41.2% of the respondents, respectively. The standardized measures regularly used by the most respondents were the single-leg stance test (79.1%), the Berg Balance Scale (45.0%), and the Timed “Up & Go” Test (27.6%). There was considerable variation in the components of balance assessed and measures used by respondents treating individuals in the orthopedic, neurologic, geriatric, and general rehabilitation populations. Limitations The survey provides quantitative data about what is done to assess balance, but does not explain the factors influencing current practice. Conclusions Many important components of balance and standardized measures are regularly used by physical therapists to assess balance. Further research, however, is needed to understand the factors contributing to the relatively lower rates of assessing reactive control, the component of balance most directly responsible for avoiding a fall. PMID:21868613

In situ coral reef oxygen metabolism: an eddy correlation study.

Directory of Open Access Journals (Sweden)

Matthew H Long

Full Text Available Quantitative studies of coral reefs are challenged by the three-dimensional hard structure of reefs and the high spatial variability and temporal dynamics of their metabolism. We used the non-invasive eddy correlation technique to examine respiration and photosynthesis rates, through O2 fluxes, from reef crests and reef slopes in the Florida Keys, USA. We assessed how the photosynthesis and respiration of different reef habitats is controlled by light and hydrodynamics. Numerous fluxes (over a 0.25 h period were as high as 4500 mmol O2 m(-2 d(-1, which can only be explained by efficient light utilization by the phototrophic community and the complex canopy structure of the reef, having a many-fold larger surface area than its horizontal projection. Over diel cycles, the reef crest was net autotrophic, whereas on the reef slope oxygen production and respiration were balanced. The autotrophic nature of the shallow reef crests implies that the export of organics is an important source of primary production for the larger area. Net oxygen production on the reef crest was proportional to the light intensity, up to 1750 µmol photons m(-2 s(-1 and decreased thereafter as respiration was stimulated by high current velocities coincident with peak light levels. Nighttime respiration rates were also stimulated by the current velocity, through enhanced ventilation of the porous framework of the reef. Respiration rates were the highest directly after sunset, and then decreased during the night suggesting that highly labile photosynthates produced during the day fueled early-night respiration. The reef framework was also important to the acquisition of nutrients as the ambient nitrogen stock in the water had sufficient capacity to support these high production rates across the entire reef width. These direct measurements of complex reefs systems yielded high metabolic rates and dynamics that can only be determined through in situ, high temporal resolution

Heat balance studies on sea ice near Syowa Station, East Antarctica

OpenAIRE

Ishikawa,Nobuyoshi; Kobayashi,Shun'ichi; Ohta,Tetsuo; Kawaguchi,Sadao

1982-01-01

Heat balance studies were carried out on the Antarctic sea ice surface in the austral spring and summer of 1980. The surface albedo of sea ice covered by a thin snow-layer was kept nearly constant (around 0.8) in spring, but in summer it was reduced to the same value as that of bare ice owing to the change of the surface properties with a great increase in the amount of absorbed net radiation. Variations of heat balance components were presented for every 10 days and two seasons in this paper.

Metabolic and hormonal consequences of two different meals after a moderate intensity exercise bout in obese prepubertal children.

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Maffeis, C; Bonadonna, R; Maschio, M; Aiello, G; Tommasi, M; Marigliano, M; Fornari, E; Morandi, A

2013-07-01

To investigate the relationship between postprandial nutrient balance, satiety and hormone changes induced by two different meals taken after a moderate intensity exercise bout. Ten prepubertal obese children participated in the study. The experiment was designed as a cross-over study for repeated measures. Each test period lasted five consecutive hours during which the children were under medical supervision. The effects of two isocaloric meals were compared after a moderate intensity exercise (4 multiples of resting metabolic rate, 30 min, cycling): a low-fat/high-carbohydrate meal (meal A) and a high-fat/low-carbohydrate meal (meal B). Pre and postprandial (3 h) substrate oxidation, biochemical parameters, gastrointestinal hormone concentrations and appetite were measured. The main results were: (i) higher fat balance (5.1±5.0 vs -5.0±6.6 g, P=0.001) and lower carbohydrate balance after meal B than A (-9.7±13.3 vs 11.3±18.3 g, Pvs -13.9±20.2 kcal, Pvs -169.5±1633.7 mg*180 min/dl, Pvs 478.8±638.3 pmol*180 min/l, Plow-carbohydrate ratio had a less favorable metabolic impact than an isoenergetic, isoproteic low-fat/high-carbohydrate meal.

BALANCE

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Carmichael, H.

1953-01-01

A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

Effect of diet on maintenance of acid-basal balance in blood of dairy cows

Directory of Open Access Journals (Sweden)

Gaál T.

2003-01-01

Full Text Available High-performance breeds of ruminants often exhibit production disorders which can be accompanied by a disturbed acid-basal balance. Most of the disorders in the acid-basal balance are closely related to digressions in the diet norms of these animals. A deficiency or surplus of energy equally cause disorders in the acid-basal status of the organism. Metabolic acidosis is the most frequent of the four types of basic disorders in the acid-basal balance in ruminants. It appears as a consequence of rumen acidosis, ketosis, or diarrhea. Acute disorders in the acid-basal balance are far more dangerous than chronic ones. Therapy of the basic diseases is generally sufficient compensation for the effects of the acid-basal disorders, but in certain cases it is necessary to perform alkalization, that is, acidification of the rumen content using the necessary preparations.

Metabolic rate and its relationship with ascites in chicken genotypes

NARCIS (Netherlands)

Malan, D.D.; Scheele, C.W.; Buyse, J.; Kwakernaak, C.; Siebrits, F.K.; Klis, van der J.D.; Decuypere, E.

2003-01-01

This review addresses the suggestion that the decline in dairy reproductive performance, as increasingly observed these days, may be due to a hampered process of metabolic adaptation in early lactating cows. In our opinion, adaptation to the negative energy balance is a gradual process. Because

Metabolic engineering of deinococcus radiodurans based on computational analysis and functional genomics

Energy Technology Data Exchange (ETDEWEB)

Edwards, Jeremy, S.

2005-02-02

The objective of our work is to develop novel computational tools to analyze the Deinococcus radiodurans DNA repair pathways and the influence of the metabolic flux distribution on DNA repair. These tools will be applied to provide insights for metabolic engineering of strains capable of growing under nutrient poor conditions similar to those found in mixed contaminant sites of interest to the DOE. Over the entire grant period we accomplished all our specific aims and were also able to pursue new directions of research. Below, I will list the major accomplishments over the previous 3 years. (1) Performed Monte Carlo Simulations of RecA Mediated Pairing of Homologous DNA Molecules. (2) Developed a statistical approach to study the gene expression data from D. radiodurans. We have been studying the data from John Batista's. (3) Developed an expression profiling technology to generate very accurate and precise expression data. We followed up on results from John Batista's group using this approach. (4) Developed and put online a database for metabolic reconstructions. (5) We have developed and applied new Monte Carlo algorithms that are optimized for studying biological systems. (6) We developed a flux balance model for the D. radiodurans metabolic network

Balanced scorecard application in the health care industry: a case study.

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Kocakülâh, Mehmet C; Austill, A David

2007-01-01

Balanced scorecards became a popular strategic performance measurement and management tool in the 1990s by Robert Kaplan and David Norton. Mainline companies accepted balanced scorecards quickly, but health care organizations were slow to adopt them for use. A number of problems face the health care industry, including cost structure, payor limitations and constraints, and performance and quality issues that require changes in how health care organizations, both profit and nonprofit, manage operations. This article discusses balanced scorecards generally from theoretical and technical views, and why they should be used by health care organizations. The authors argue that balanced scorecards are particularly applicable to hospitals, clinics, and other health care companies. Finally, the authors perform a case study of the development, implementation, and use of balance scorecards by a regional Midwestern health care system. The positive and negative aspects of the subject's balanced scorecard are discussed. Leaders in today's health care industry are under great pressure to meet their financial goals. The industry is faced with financial pressures from consumers, insurers, and governments. Inflation in the industry is much higher than it is within the overall economy. Employers can no longer bear the burden of rising group health insurance costs for its employees. Too many large companies have used bankruptcy law as a shield to reduce or shift some of their legal obligations to provide health insurance coverage to present or retired employees. Stakeholders of health care providers are demanding greater control over costs. As the segment of un- or underinsured within the United States becomes larger as a percentage of the population, voters are seriously beginning to demand some form of national health insurance, which will drastically change the health care industry.

Balance Training Reduces Brain Activity during Motor Simulation of a Challenging Balance Task in Older Adults: An fMRI Study.

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Ruffieux, Jan; Mouthon, Audrey; Keller, Martin; Mouthon, Michaël; Annoni, Jean-Marie; Taube, Wolfgang

2018-01-01

Aging is associated with a shift from an automatic to a more cortical postural control strategy, which goes along with deteriorations in postural stability. Although balance training has been shown to effectively counteract these behavioral deteriorations, little is known about the effect of balance training on brain activity during postural tasks in older adults. We, therefore, assessed postural stability and brain activity using fMRI during motor imagery alone (MI) and in combination with action observation (AO; i.e., AO+MI) of a challenging balance task in older adults before and after 5 weeks of balance training. Results showed a nonsignificant trend toward improvements in postural stability after balance training, accompanied by reductions in brain activity during AO+MI of the balance task in areas relevant for postural control, which have been shown to be over-activated in older adults during (simulation of) motor performance, including motor, premotor, and multisensory vestibular areas. This suggests that balance training may reverse the age-related cortical over-activations and lead to changes in the control of upright posture toward the one observed in young adults.

More to NAD+ than meets the eye: A regulator of metabolic pools and gene expression in Arabidopsis.

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Gakière, Bertrand; Fernie, Alisdair R; Pétriacq, Pierre

2018-01-05

Since its discovery more than a century ago, nicotinamide adenine dinucleotide (NAD + ) is recognised as a fascinating cornerstone of cellular metabolism. This ubiquitous energy cofactor plays vital roles in metabolic pathways and regulatory processes, a fact emphasised by the essentiality of a balanced NAD + metabolism for normal plant growth and development. Research on the role of NAD in plants has been predominantly carried out in the model plant Arabidopsis thaliana (Arabidopsis) with emphasis on the redox properties and cellular signalling functions of the metabolite. This review examines the current state of knowledge concerning how NAD can regulate both metabolic pools and gene expression in Arabidopsis. Particular focus is placed on recent studies highlighting the complexity of metabolic regulations involving NAD, more particularly in the mitochondrial compartment, and of signalling roles with respect to interactions with environmental fluctuations most specifically those involving plant immunity. Copyright © 2018 Elsevier Inc. All rights reserved.

Sense and nonsense in metabolic control of reproduction.

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Schneider, Jill E; Klingerman, Candice M; Abdulhay, Amir

2012-01-01

An exciting synergistic interaction occurs among researchers working at the interface of reproductive biology and energy homeostasis. Reproductive biologists benefit from the theories, experimental designs, and methodologies used by experts on energy homeostasis while they bring context and meaning to the study of energy homeostasis. There is a growing recognition that identification of candidate genes for obesity is little more than meaningless reductionism unless those genes and their expression are placed in a developmental, environmental, and evolutionary context. Reproductive biology provides this context because metabolic energy is the most important factor that controls reproductive success and gonadal hormones affect energy intake, storage, and expenditure. Reproductive hormone secretion changes during development, and reproductive success is key to evolutionary adaptation, the process that most likely molded the mechanisms that control energy balance. It is likely that by viewing energy intake, storage, and expenditure in the context of reproductive success, we will gain insight into human obesity, eating disorders, diabetes, and other pathologies related to fuel homeostasis. This review emphasizes the metabolic hypothesis: a sensory system monitors the availability of oxidizable metabolic fuels and orchestrates behavioral motivation to optimize reproductive success in environments where energy availability fluctuates or is unpredictable.

Environmental and genetic influences on flight metabolic rate in the honey bee, Apis mellifera.

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Harrison, Jon F; Fewell, Jennifer H

2002-10-01

Flying honey bees demonstrate highly variable metabolic rates. The lowest reported values (approximately 0.3 Wg(-1)) occur in tethered bees generating the minimum lift to support their body weight, free-flying 2-day old bees, winter bees, or bees flying at high air temperatures (45 degrees C). The highest values (approximately 0.8 Wg(-1)) occur in foragers that are heavily loaded or flying in low-density air. In different studies, flight metabolic rate has increased, decreased, or remained constant with air temperature. Current research collectively suggests that this variation occurs because flight metabolic rates decrease at thorax temperatures above or below 38 degrees C. At 30 degrees C, approximately 30% of colonial energy is spent during typical foraging, so variation in flight metabolic rate can strongly affect colony-level energy balance. Higher air temperatures tend to increase colonial net gain rates, efficiencies and honey storage rates due to lower metabolic rates during flight and in the hive. Variation in flight metabolism has a clear genetic basis. Different genetic strains of honey bees often differ in flight metabolic rate, and these differences in flight physiology can be correlated with foraging effort, suggesting a possible pathway for selection effects on flight metabolism.

Construction and analysis of a genome-scale metabolic network for Bacillus licheniformis WX-02.

Science.gov (United States)

Guo, Jing; Zhang, Hong; Wang, Cheng; Chang, Ji-Wei; Chen, Ling-Ling

2016-05-01

We constructed the genome-scale metabolic network of Bacillus licheniformis (B. licheniformis) WX-02 by combining genomic annotation, high-throughput phenotype microarray (PM) experiments and literature-based metabolic information. The accuracy of the metabolic network was assessed by an OmniLog PM experiment. The final metabolic model iWX1009 contains 1009 genes, 1141 metabolites and 1762 reactions, and the predicted metabolic phenotypes showed an agreement rate of 76.8% with experimental PM data. In addition, key metabolic features such as growth yield, utilization of different substrates and essential genes were identified by flux balance analysis. A total of 195 essential genes were predicted from LB medium, among which 149 were verified with the experimental essential gene set of B. subtilis 168. With the removal of 5 reactions from the network, pathways for poly-γ-glutamic acid (γ-PGA) synthesis were optimized and the γ-PGA yield reached 83.8 mmol/h. Furthermore, the important metabolites and pathways related to γ-PGA synthesis and bacterium growth were comprehensively analyzed. The present study provides valuable clues for exploring the metabolisms and metabolic regulation of γ-PGA synthesis in B. licheniformis WX-02. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Balance confidence is related to features of balance and gait in individuals with chronic stroke

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Schinkel-Ivy, Alison; Wong, Jennifer S.; Mansfield, Avril

2016-01-01

Reduced balance confidence is associated with impairments in features of balance and gait in individuals with sub-acute stroke. However, an understanding of these relationships in individuals at the chronic stage of stroke recovery is lacking. This study aimed to quantify relationships between balance confidence and specific features of balance and gait in individuals with chronic stroke. Participants completed a balance confidence questionnaire and clinical balance assessment (quiet standing, walking, and reactive stepping) at 6 months post-discharge from inpatient stroke rehabilitation. Regression analyses were performed using balance confidence as a predictor variable and quiet standing, walking, and reactive stepping outcome measures as the dependent variables. Walking velocity was positively correlated with balance confidence, while medio-lateral centre of pressure excursion (quiet standing) and double support time, step width variability, and step time variability (walking) were negatively correlated with balance confidence. This study provides insight into the relationships between balance confidence and balance and gait measures in individuals with chronic stroke, suggesting that individuals with low balance confidence exhibited impaired control of quiet standing as well as walking characteristics associated with cautious gait strategies. Future work should identify the direction of these relationships to inform community-based stroke rehabilitation programs for individuals with chronic stroke, and determine the potential utility of incorporating interventions to improve balance confidence into these programs. PMID:27955809

Microalgal bioengineering for sustainable energy development: Recent transgenesis and metabolic engineering strategies.

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Banerjee, Chiranjib; Singh, Puneet Kumar; Shukla, Pratyoosh

2016-03-01

Exploring the efficiency of algae to produce remarkable products can be directly benefitted by studying its mechanism at systems level. Recent advents in biotechnology like flux balance analysis (FBA), genomics and in silico proteomics minimize the wet lab exertion. It is understood that FBA predicts the metabolic products, metabolic pathways and alternative pathway to maximize the desired product, and these are key components for microalgae bio-engineering. This review encompasses recent transgenesis techniques and metabolic engineering strategies applied to different microalgae for improving different traits. Further it also throws light on RNAi and riboswitch engineering based methods which may be advantageous for high throughput microalgal research. A valid and optimally designed microalga can be developed where every engineering strategies meet each other successfully and will definitely fulfill the market needs. It is also to be noted that Omics (viz. genetic and metabolic manipulation with bioinformatics) should be integrated to develop a strain which could prove to be a futuristic solution for sustainable development for energy. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

TPSS plasma engineering studies: profile effects and plasma power balance

International Nuclear Information System (INIS)

Borowski, S.K.; Strickler, D.J.

1985-01-01

A computationally fast profile-averaged, steady-state plasma model has been developed to allow studies of radial effects in ignited and driven tokamak systems. This code was used to search for the smallest size tokamak consistent with power balance calculations

Clinical Research Strategies for Fructose Metabolism12

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Laughlin, Maren R.; Bantle, John P.; Havel, Peter J.; Parks, Elizabeth; Klurfeld, David M.; Teff, Karen; Maruvada, Padma

2014-01-01

Fructose and simple sugars are a substantial part of the western diet, and their influence on human health remains controversial. Clinical studies in fructose nutrition have proven very difficult to conduct and interpret. NIH and USDA sponsored a workshop on 13–14 November 2012, “Research Strategies for Fructose Metabolism,” to identify important scientific questions and parameters to be considered while designing clinical studies. Research is needed to ascertain whether there is an obesogenic role for fructose-containing sugars via effects on eating behavior and energy balance and whether there is a dose threshold beyond which these sugars promote progression toward diabetes and liver and cardiovascular disease, especially in susceptible populations. Studies tend to fall into 2 categories, and design criteria for each are described. Mechanistic studies are meant to validate observations made in animals or to elucidate the pathways of fructose metabolism in humans. These highly controlled studies often compare the pure monosaccharides glucose and fructose. Other studies are focused on clinically significant disease outcomes or health behaviors attributable to amounts of fructose-containing sugars typically found in the American diet. These are designed to test hypotheses generated from short-term mechanistic or epidemiologic studies and provide data for health policy. Discussion brought out the opinion that, although many mechanistic questions concerning the metabolism of monosaccharide sugars in humans remain to be addressed experimentally in small highly controlled studies, health outcomes research meant to inform health policy should use large, long-term studies using combinations of sugars found in the typical American diet rather than pure fructose or glucose. PMID:24829471

The study of urban metabolism and its applications to urban planning and design

International Nuclear Information System (INIS)

Kennedy, C.; Pincetl, S.; Bunje, P.

2011-01-01

Following formative work in the 1970s, disappearance in the 1980s, and reemergence in the 1990s, a chronological review shows that the past decade has witnessed increasing interest in the study of urban metabolism. The review finds that there are two related, non-conflicting, schools of urban metabolism: one following Odum describes metabolism in terms of energy equivalents; while the second more broadly expresses a city's flows of water, materials and nutrients in terms of mass fluxes. Four example applications of urban metabolism studies are discussed: urban sustainability indicators; inputs to urban greenhouse gas emissions calculation; mathematical models of urban metabolism for policy analysis; and as a basis for sustainable urban design. Future directions include fuller integration of social, health and economic indicators into the urban metabolism framework, while tackling the great sustainability challenge of reconstructing cities. - This paper presents a chronological review of urban metabolism studies and highlights four areas of application.

In vivo 13C MRS studies of carbohydrate metabolism

International Nuclear Information System (INIS)

Halliday, Jane

2003-01-01

The work described in this thesis was performed by the author, except where indicated, within the Magnetic Resonance Centre at the University of Nottingham during the period between October 1999 and October 2002. Although much is known about the major pathways of carbohydrate metabolism, there is still much to be learnt about the exact mechanisms of many of these pathways. Of particular interest is how these pathways are modified under different physiological conditions and in diseased states. 13 C NMR spectroscopy provides a non-invasive means for studying carbohydrate metabolism in vivo, and the work presented within this thesis gives two such examples of this in human subjects. Natural abundance 13 C NMR spectroscopy was used to measure glycogen levels in gastrocnemius muscle. The diurnal changes in response to mixed meals were measured in both type 2 diabetic subjects and age and weight matched controls. Metabolic studies were performed to complement the NMR measurements. The data obtained in these studies show the effect of the failure of muscle glucose storage upon post-prandial hyperglycaemia despite a supra-normal increase in plasma insulin in type 2 diabetes. 13 C NMR spectroscopy was also used to study cerebral metabolism. Accumulation of 13 C label into glutamate and glutamine following infusion of [1 1 3 C] glucose allows the determination of the rates of the TCA cycle (F TCA ) and neurotransmitter cycling (F cyc ). These rates were measured in the visual cortex under control and activated conditions. The increases seen in F TCA upon activation, together with the lack of label accumulation in lactate, suggest that cerebral glucose metabolism is oxidative, even during strong activation. No conclusion can be made as to whether or not a similar increase is seen in F cyc due to the large associated errors in these values. (author)

Metabolic Phenotyping of Diet and Dietary Intake.

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Brignardello, J; Holmes, E; Garcia-Perez, I

Nutrition provides the building blocks for growth, repair, and maintenance of the body and is key to maintaining health. Exposure to fast foods, mass production of dietary components, and wider importation of goods have challenged the balance between diet and health in recent decades, and both scientists and clinicians struggle to characterize the relationship between this changing dietary landscape and human metabolism with its consequent impact on health. Metabolic phenotyping of foods, using high-density data-generating technologies to profile the biochemical composition of foods, meals, and human samples (pre- and postfood intake), can be used to map the complex interaction between the diet and human metabolism and also to assess food quality and safety. Here, we outline some of the techniques currently used for metabolic phenotyping and describe key applications in the food sciences, ending with a broad outlook at some of the newer technologies in the field with a view to exploring their potential to address some of the critical challenges in nutritional science. © 2017 Elsevier Inc. All rights reserved.

Magnesium balances and 28Mg studies in man

International Nuclear Information System (INIS)

Spencer, H.; Schwartz, R.; Osis, D.

1988-01-01

The intestinal absorption of magnesium was determined under strictly controlled dietary conditions in patients with normal renal function and also in patients with chronic renal failure. The average net absorption of magnesium of patients with normal renal function, expressed as percent of the magnesium intake, was 48.5%, while that of patients with chronic renal failure was significantly lower, 17%. Increasing the calcium intake from a low calcium intake of 200 mg/day to different higher intake levels up to 2000 mg/day did not change the magnesium balance nor the net absorption of magnesium of both types of patients. The lack of effect of the higher calcium intake on the absorption of magnesium was confirmed in 28 Mg studies in which an oral dose of 28 Mg, as the chloride, was given. The excretion of the absorbed magnesium into the intestine, the endogenous fecal magnesium, was low. Also, increasing the phosphorus intake up to 2000 mg/day in subjects with normal renal function did not affect the magnesium balance, regardless of the calcium intake

Nuclear magnetic resonance studies of metabolic regulation

International Nuclear Information System (INIS)

Sillerud, L.O.; Han, C.H.; Whaley, T.W.

1983-01-01

Nuclear magnetic resonance (NMR) techniques for the detection of the metabolic transformations of biological compounds labeled with stable isotopes, particularly carbon-13 have been explored. We have studied adipose tissue in the intact rat, the exteriorized epididymal fat pad, and the isolated adipocyte. Triacylglycerol metabolism in adipose tissue is regulated by lipogenic factors (insulin, corticosterone, thyroxine, and growth hormone) and lipolytic factors (glucagon and catecholamines). The synthesis of triglyceride from 5.5 mM glucose was stimulated by about 4-fold by 10 nM insulin. Triglyceride synthesis from glucose in the presence of insulin occurred at a rate of 330 nmol/hr/10 6 cells. Since the NMR signals from free and esterified fatty acids and glycerol are distinct, we could directly measure the rate of hormone-stimulated lipolysis. Epinephrine (10 μM) gave a lipolytic rate of 0.30 μmol/hr/10 6 cells as monitored by free-glycerol appearance in the medium. 13 C NMR provides a superior method for the measurement of triglyceride metabolism since it directly measures the changes in the substrates and products in situ

A comparative study on androgen metabolism in three invertebrate species.

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Janer, G; LeBlanc, G A; Porte, C

2005-09-15

A comparative approach was taken in this study to evaluate androgen (androstenedione and testosterone) metabolism in three invertebrate species: the gastropod Marisa cornuarietis, the amphipod Hyalella azteca, and the echinoderm Paracentrotus lividus. The existence of 17beta/3beta-hydroxysteroid dehydrogenase (HSD) and 5alpha-reductase catalyzed reactions was demonstrated in all three species. Androstenedione was primarily converted to 5alpha-androstanedione in M. cornuarietis, while it was primarily metabolized to testosterone in P. lividus and H. azteca. In addition, and consistent with vertebrate findings, tissue specific pathways and sexual dimorphism in androgen metabolism were observed. Namely, testosterone was metabolized to dihydrotestosterone in P. lividus gonads (via 5alpha-reductase), and metabolized to 4-androstene-3beta,17beta-diol in the digestive tube (via 3beta-hydroxysteroid dehydrogenase). Furthermore, the synthesis of 17beta-reduced metabolites of androstenedione (testosterone and dihydrotestosterone) was 3- to 4-fold higher in males of M. cornuarietis than in females. Organotin compounds, which have been shown to interfere with some aspects of androgen metabolism, had no major effect on testosterone metabolism in any of the three species. Fenarimol enhanced 5alpha-reductase-mediated catalysis in gonads of P. lividus. Overall, results demonstrate the ubiquity of some androgen biotransformation processes in invertebrates and reveals interphyla differences in androgen metabolic pathways, and different sensitivity of these pathways to some xenobiotics.

Skeletal scintigraphy and quantitative tracer studies in metabolic bone disease

Science.gov (United States)

Fogelman, Ignac

Bone scan imaging with the current bone seeking radiopharmaceuticals, the technetium-99m labelled diphosphonates, has dramatically improved our ability to evaluate skeletal pathology. In this thesis, chapter 1 presents a review of the history of bone scanning, summarises present concepts as to the mechanism of uptake of bone seeking agents and briefly illustrates the role of bone scanning in clinical practice. In chapter 2 the applications of bone scan imaging and quantitative tracer techniques derived from the bone scan in the detection of metabolic bone disease are discussed. Since skeletal uptake of Tc-99m diphosphonate depends upon skeletal metabolism one might expect that the bone scan would be of considerable value in the assessment of metabolic bone disease. However in these disorders the whole skeleton is often diffusely involved by the metabolic process and simple visual inspection of the scan image may not reveal the uniformly increased uptake of tracer. Certain patterns of bone scan abnormality have, however, been reported in patients with primary hyperparathyroidism and renal osteo-dystrophy; the present studies extend these observations and introduce the concept of "metabolic features" which are often recognisable in conditions with generalised increased bone turnover. As an aid to systematic recognition of these features on a given bone scan image a semi-quantitative scoring system, the metabolic index, was introduced. The metabolic index allowed differentiation between various groups of patients with metabolic disorders and a control population. In addition, in a bone scan study of patients with acromegaly, it was found that the metabolic index correlated well with disease activity as measured by serum growth hormone levels. The metabolic index was, however, found to be a relatively insensitive means of identifying disease in individual patients. Patients with increased bone turnover will have an absolute increase in skeletal uptake of tracer. As a

Hypothalamic AMPK and fatty acid metabolism mediate thyroid regulation of energy balance

OpenAIRE

López, Miguel; Varela, Luis; Vázquez, María J; Rodríguez-Cuenca, Sergio; González, Carmen R; Velagapudi, Vidya R; Morgan, Donald A; Schoenmakers, Erik; Agassandian, Khristofor; Lage, Ricardo; de Morentin, Pablo Blanco Martínez; Tovar, Sulay; Nogueiras, Rubén; Carling, David; Lelliott, Christopher

2010-01-01

Thyroid hormones have widespread cellular effects; however it is unclear whether their effects on the central nervous system (CNS) contribute to global energy balance. Here, we demonstrate that either whole body hyperthyroidism or central administration of triiodothyronine (T3) decreases the activity of hypothalamic AMP-activated protein kinase (AMPK), increases sympathetic nervous system (SNS) activity and upregulates thermogenic markers in brown adipose tissue (BAT). Inhibition of the lipog...

MicrobesFlux: a web platform for drafting metabolic models from the KEGG database

Directory of Open Access Journals (Sweden)

Feng Xueyang

2012-08-01

Full Text Available Abstract Background Concurrent with the efforts currently underway in mapping microbial genomes using high-throughput sequencing methods, systems biologists are building metabolic models to characterize and predict cell metabolisms. One of the key steps in building a metabolic model is using multiple databases to collect and assemble essential information about genome-annotations and the architecture of the metabolic network for a specific organism. To speed up metabolic model development for a large number of microorganisms, we need a user-friendly platform to construct metabolic networks and to perform constraint-based flux balance analysis based on genome databases and experimental results. Results We have developed a semi-automatic, web-based platform (MicrobesFlux for generating and reconstructing metabolic models for annotated microorganisms. MicrobesFlux is able to automatically download the metabolic network (including enzymatic reactions and metabolites of ~1,200 species from the KEGG database (Kyoto Encyclopedia of Genes and Genomes and then convert it to a metabolic model draft. The platform also provides diverse customized tools, such as gene knockouts and the introduction of heterologous pathways, for users to reconstruct the model network. The reconstructed metabolic network can be formulated to a constraint-based flux model to predict and analyze the carbon fluxes in microbial metabolisms. The simulation results can be exported in the SBML format (The Systems Biology Markup Language. Furthermore, we also demonstrated the platform functionalities by developing an FBA model (including 229 reactions for a recent annotated bioethanol producer, Thermoanaerobacter sp. strain X514, to predict its biomass growth and ethanol production. Conclusion MicrobesFlux is an installation-free and open-source platform that enables biologists without prior programming knowledge to develop metabolic models for annotated microorganisms in the KEGG

Physical Fitness and Metabolic Syndrome in Children with Repaired Congenital Heart Disease Compared with Healthy Children.

Science.gov (United States)

Zaqout, Mahmoud; Vandekerckhove, Kristof; Michels, Nathalie; Bove, Thierry; François, Katrien; De Wolf, Daniel

2017-12-01

To determine whether children who underwent surgery for congenital heart disease (CHD) are as fit as their peers. We studied 66 children (6-14 years) who underwent surgery for ventricular septal defect (n = 19), coarctation of aorta (n = 10), tetralogy of Fallot (n = 15), and transposition of great arteries (n = 22); and 520 healthy children (6-12 years). All children performed physical fitness tests: cardiorespiratory fitness, muscular strength, balance, flexibility, and speed. Metabolic score was assessed through z-score standardization using 4 components: waist circumference, blood pressure, blood lipids, and insulin resistance. Assessment also included self-reported and accelerometer-measured physical activity. Linear regression analyses with group (CHD vs control) as a predictor were adjusted for age, body mass index, physical activity, and parental education. Measured physical activity level, body mass index, cardiorespiratory fitness, flexibility, and total metabolic score did not differ between children with CHD and controls, whereas reported physical activity was greater in the CHD group than control group. Boys with CHD were less strong in upper muscular strength, speed, and balance, whereas girls with CHD were better in lower muscular strength and worse in balance. High-density lipoprotein was greater in boys and girls with CHD, whereas boys with CHD showed unhealthier glucose homeostasis. Appropriate physical fitness was achieved in children after surgery for CHD, especially in girls. Consequently, children with CHD were not at increased total metabolic risk. Lifestyle counseling should be part of every patient interaction. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparative evaluation of atom mapping algorithms for balanced metabolic reactions: application to Recon 3D.

Science.gov (United States)

Preciat Gonzalez, German A; El Assal, Lemmer R P; Noronha, Alberto; Thiele, Ines; Haraldsdóttir, Hulda S; Fleming, Ronan M T

2017-06-14

The mechanism of each chemical reaction in a metabolic network can be represented as a set of atom mappings, each of which relates an atom in a substrate metabolite to an atom of the same element in a product metabolite. Genome-scale metabolic network reconstructions typically represent biochemistry at the level of reaction stoichiometry. However, a more detailed representation at the underlying level of atom mappings opens the possibility for a broader range of biological, biomedical and biotechnological applications than with stoichiometry alone. Complete manual acquisition of atom mapping data for a genome-scale metabolic network is a laborious process. However, many algorithms exist to predict atom mappings. How do their predictions compare to each other and to manually curated atom mappings? For more than four thousand metabolic reactions in the latest human metabolic reconstruction, Recon 3D, we compared the atom mappings predicted by six atom mapping algorithms. We also compared these predictions to those obtained by manual curation of atom mappings for over five hundred reactions distributed among all top level Enzyme Commission number classes. Five of the evaluated algorithms had similarly high prediction accuracy of over 91% when compared to manually curated atom mapped reactions. On average, the accuracy of the prediction was highest for reactions catalysed by oxidoreductases and lowest for reactions catalysed by ligases. In addition to prediction accuracy, the algorithms were evaluated on their accessibility, their advanced features, such as the ability to identify equivalent atoms, and their ability to map hydrogen atoms. In addition to prediction accuracy, we found that software accessibility and advanced features were fundamental to the selection of an atom mapping algorithm in practice.

Work Life Balance Among Nurse Educators Towards Quality Life: A Mixed Method Study

OpenAIRE

Eddieson Astodello Pasay-an; Petelyne Pacio Pangket; Juanita Yudong Nialla; Lynn B Laban

2014-01-01

Work-Life balance is completely an imminent problem that needs to be addressed across all organizations. The nursing field, especially nurses in the Academe is not excused due to multiple roles they are facing. This study was intended to determine and explore the work life balance among nurse educators towards quality life. The respondents of the study were the nurse educators of the Schools of Nursing in the city Baguio and the province of Benguet, Philippines. The research utilized Mixed Me...

[Relation between physical activity, weight balance and breast cancer].

Science.gov (United States)

Maître, Carole

2013-05-01

Many epidemiologic studies, with a good methodology, support the evidence of the positive role of regular physical activity on primary and tertiary prevention of breast cancer on the risk of recurrence and mortality. This relation depends on the level of total energy expenditure by week, which helps balance weight on lifetime, an essential part of benefit. The beneficial effects of physical activity are linked to many interrelated additional mechanisms: in a short-term, contraction of skeletal muscles involves aerobic metabolism which utilizes glucose and amino acids like glutamine, improves insulin sensitivity and lowers plasma insulin; in a long-term, physical activity produces favorable changes in body composition, decreasing body fat and increasing lean mass. That is a key point to reduce the intake of energy substrates stimulating carcinogenesis, to improve insulin sensitivity, to change the ratio of leptin and adiponectin, to enhance cellular immunity and to block cellular pathways of cell proliferation and angiogenesis. Maintaining a healthy weight through regular physical activity well balanced with energy intake is it a goal for prevention of breast cancer. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Thermodynamics-based Metabolite Sensitivity Analysis in metabolic networks.

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Kiparissides, A; Hatzimanikatis, V

2017-01-01

The increasing availability of large metabolomics datasets enhances the need for computational methodologies that can organize the data in a way that can lead to the inference of meaningful relationships. Knowledge of the metabolic state of a cell and how it responds to various stimuli and extracellular conditions can offer significant insight in the regulatory functions and how to manipulate them. Constraint based methods, such as Flux Balance Analysis (FBA) and Thermodynamics-based flux analysis (TFA), are commonly used to estimate the flow of metabolites through genome-wide metabolic networks, making it possible to identify the ranges of flux values that are consistent with the studied physiological and thermodynamic conditions. However, unless key intracellular fluxes and metabolite concentrations are known, constraint-based models lead to underdetermined problem formulations. This lack of information propagates as uncertainty in the estimation of fluxes and basic reaction properties such as the determination of reaction directionalities. Therefore, knowledge of which metabolites, if measured, would contribute the most to reducing this uncertainty can significantly improve our ability to define the internal state of the cell. In the present work we combine constraint based modeling, Design of Experiments (DoE) and Global Sensitivity Analysis (GSA) into the Thermodynamics-based Metabolite Sensitivity Analysis (TMSA) method. TMSA ranks metabolites comprising a metabolic network based on their ability to constrain the gamut of possible solutions to a limited, thermodynamically consistent set of internal states. TMSA is modular and can be applied to a single reaction, a metabolic pathway or an entire metabolic network. This is, to our knowledge, the first attempt to use metabolic modeling in order to provide a significance ranking of metabolites to guide experimental measurements. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier

Impact of hypothalamic reactive oxygen species in the control of energy metabolism and food intake

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Anne eDrougard

2015-02-01

Full Text Available Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC and agouti-related protein (AgRP/neuropeptide Y (NPY neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,..., neurotransmitters and nutrients (glucose, lipids,.... The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes.In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.

Impact of hypothalamic reactive oxygen species in the regulation of energy metabolism and food intake.

Science.gov (United States)

Drougard, Anne; Fournel, Audren; Valet, Philippe; Knauf, Claude

2015-01-01

Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites) from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS) as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC) and agouti-related protein (AgRP)/neuropeptide Y (NPY) neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,…), neurotransmitters and nutrients (glucose, lipids,…). The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes. In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.

A Comparative Study of Load Balancing Algorithms in Cloud Computing Environment

OpenAIRE

Katyal, Mayanka; Mishra, Atul

2014-01-01

Cloud Computing is a new trend emerging in IT environment with huge requirements of infrastructure and resources. Load Balancing is an important aspect of cloud computing environment. Efficient load balancing scheme ensures efficient resource utilization by provisioning of resources to cloud users on demand basis in pay as you say manner. Load Balancing may even support prioritizing users by applying appropriate scheduling criteria. This paper presents various load balancing schemes in differ...

Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

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Chris Rissel

2013-01-01

Full Text Available Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT test (decision time and response time, leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited into a 12-week cycling program. The same pre- and postmeasures as used in Study 1 were collected. Results. Study 1: participants who had cycled in the last month performed significantly better on measures of decision time and response time. Study 2: cycling at least one hour a week was associated with significant improvements in balance (decision time and response time and timed single leg standing. Conclusions. Cycling by healthy older adults appears promising for improving risk factors for falls.

Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

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Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

2013-01-01

Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited into a 12-week cycling program. The same pre- and postmeasures as used in Study 1 were collected. Results. Study 1: participants who had cycled in the last month performed significantly better on measures of decision time and response time. Study 2: cycling at least one hour a week was associated with significant improvements in balance (decision time and response time) and timed single leg standing. Conclusions. Cycling by healthy older adults appears promising for improving risk factors for falls. PMID:23690805

Fulfillment of work-life balance from the organizational perspective: a case study.

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Mazerolle, Stephanie M; Goodman, Ashley

2013-01-01

Researchers studying work-life balance have examined policy development and implementation to create a family-friendly work environment from an individualistic perspective rather than from a cohort of employees working under the same supervisor. To investigate what factors influence work-life balance within the National Collegiate Athletic Association (NCAA) Division I clinical setting from the perspective of an athletic training staff. Qualitative study. Web-based management system. Eight athletic trainers (5 men, 3 women; age = 38 ± 7 years) in the NCAA Division I setting. Participants responded to a series of questions by journaling their thoughts and experiences. We included data-source triangulation, multiple-analyst triangulation, and peer review to establish data credibility. We analyzed the data via a grounded theory approach. Three themes emerged from the data. Family-oriented and supportive work environment was described as a workplace that fosters and encourages work-life balance through professionally and personally shared goals. Nonwork outlets included activities, such as exercise and personal hobbies, that provide time away from the role of the athletic trainer. Individualistic strategies reflected that although the athletic training staff must work together and support one another, each staff member must have his or her own personal strategies to manage personal and professional responsibilities. The foundation for a successful work environment in the NCAA Division I clinical setting potentially can center on the management style of the supervisor, especially one who promotes teamwork among his or her staff members. Although a family-friendly work environment is necessary for work-life balance, each member of the athletic training staff must have personal strategies in place to fully achieve a balance.

Fulfillment of Work-Life Balance From the Organizational Perspective: A Case Study.

Science.gov (United States)

Mazerolle, Stephanie M; Goodman, Ashley

2013-04-18

  Researchers studying work-life balance have examined policy development and implementation to create a family-friendly work environment from an individualistic perspective rather than from a cohort of employees working under the same supervisor.   To investigate what factors influence work-life balance within the National Collegiate Athletic Association (NCAA) Division I clinical setting from the perspective of an athletic training staff.   Qualitative study.   Web-based management system.   Eight athletic trainers (5 men, 3 women; age = 38 ± 7 years) in the NCAA Division I setting.   Participants responded to a series of questions by journaling their thoughts and experiences. We included data-source triangulation, multiple analyst triangulation, and peer review to establish data credibility. We analyzed the data via a grounded theory approach.   Three themes emerged from the data. Family-oriented and supportive work environment was described as a workplace that fosters and encourages work-life balance through professionally and personally shared goals. Nonwork outlets included activities, such as exercise and personal hobbies, that provide time away from the role of the athletic trainer. Individualistic strategies reflected that although the athletic training staff must work together and support one another, each staff member must have his or her own personal strategies to manage personal and professional responsibilities.   The foundation for a successful work environment in the NCAA Division I clinical setting potentially can center on the management style of the supervisor, especially one who promotes teamwork among his or her staff members. Although a family-friendly work environment is necessary for work-life balance, each member of the athletic training staff must have personal strategies in place to fully achieve a balance.

Work–family balance of Indian women software professionals: A qualitative study

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Reimara Valk

2011-03-01

Full Text Available One of the significant changes witnessed in the labour markets in India has been the entry of women IT professionals in the rapidly growing software services sector. As the women take on the role of working professional in addition to their traditional role of the homemaker, they are under great pressure to balance their work and personal lives. This study attempts to understand how work and family related factors influence the work–family balance of Indian women IT professionals. The study is based on an exploratory qualitative study of 13 women IT professionals in the software sector in Bangalore, India. The narratives reveal six major themes: familial influences on life choices; multi-role responsibilities and attempts to negotiate them; self and professional identity; work–life challenges and coping strategies; organisational policies and practices; and social support.

Career And Life-Balance Of Professional Women: A South African Study

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Thana Whitehead

2003-11-01

Full Text Available A woman’s ability to balance multiple life-roles is directly related to her physical and mental well-being, and her career performance and success. This study aims to infer a theoretical framework for the in-depth understanding of the phenomenon of life-balance in the lives of 24 South African professional women. The Grounded Theory as a qualitative method was applied to derive a theory about the phenomenon inductively. Purposeful sampling was used to identify 24 professional women. In-depth interviews and a group session were conducted to gather data, and to confirm themes and concepts on which the theoretical framework was based. It was concluded that life-balance is a life-process with a cyclical nature, and a useful tool for achieving personal growth. Life-balance is therefore not “one, single ultimate experience", but a series of individual experiences unfolding over time, which could be better described as “life-balance moments". Opsomming ‘n Vrou se vermoë om meervoudige lewensrolle te balanseer is direk verwant aan haar fisiese en geesteswelsyn en ook haar loopbaanprestasie en -sukses. Hierdie studie het ten doel om ‘n teoretiese raamwerk af te lei uit die indiepte begrip van die lewens-balansverskynsel van 24 Suid-Afrikaanse professionele vroue. Die Begronde Teorie as ‘n kwalitatiewe metode is toegepas om ‘n teoretiese model induktief van die verskynsels af te lei. Doelgerigte steekproefneming is gebruik om 24 professionele vroue te identifiseer. In-diepte onderhoude en ‘n groepsessie is gevoer om data in te samel en om die temas en konsepte waarop die teoretiese raamwerk gebaseer is, te bevestig. Daar is tot die slotsom gekom dat lewensbalans ‘n lewensproses is met ‘n sikliese aard en ‘n nuttige instrument om persoonlike groei te bewerkstellig. Lewensbalans is dus nie “een enkele beslissende erevaring" nie, maar ‘n reeks van individuele ervarings wat oor tyd ontvou en wat ten beste beskryf kan word as �

The Effect of Balance Training by Tetraks Interactive Balance System on Balance and Fall Risk in Parkinson's Patients: A Report of Four Cases.

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Balci, Nilay Çömük; Tonga, Eda; Gülşen, Mustafa

2013-09-01

This pilot study aimed to investigate the effect of balance training by Tetraks Interactive Balance System (TIBS) on balance and fall risk in patients with mild to moderate Parkinson's disease. Four patients with Parkinson's disease between the ages of 56 and 70 years (61.25±6.70) were applied balance training for 3 weeks by TIBS. Sociodemographic features and physical properties of the subjects were recorded. Their motor performance was evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS), balance was measured using the Berg Balance Scale (BBS), Functional Reach Test (FRT), Timed Up and Go Test (TUG), and the Standing on One Leg Balance Test (SOL) and, their fall risks were evaluated by TIBS. Evaluations were performed twice, before and after treatment. Following training, Parkinson's patients showed improvements in UPDRS, TUG, BBS, FRT, SOL and fall risk. Balance training by TIBS has positive effects on balance and decreases fall risk in Parkinson's disease patients.

Whey Protein Supplementation Enhances Whole Body Protein Metabolism and Performance Recovery after Resistance Exercise: A Double-Blind Crossover Study.

Science.gov (United States)

West, Daniel W D; Abou Sawan, Sidney; Mazzulla, Michael; Williamson, Eric; Moore, Daniel R

2017-07-11

No study has concurrently measured changes in free-living whole body protein metabolism and exercise performance during recovery from an acute bout of resistance exercise. We aimed to determine if whey protein ingestion enhances whole body net protein balance and recovery of exercise performance during overnight (10 h) and 24 h recovery after whole body resistance exercise in trained men. In a double-blind crossover design, 12 trained men (76 ± 8 kg, 24 ± 4 years old, 14% ± 5% body fat; means ± standard deviation (SD)) performed resistance exercise in the evening prior to consuming either 25 g of whey protein (PRO; MuscleTech 100% Whey) or an energy-matched placebo (CHO) immediately post-exercise (0 h), and again the following morning (~10 h of recovery). A third randomized trial, completed by the same participants, involving no exercise and no supplement served as a rested control trial (Rest). Participants ingested [ 15 N]glycine to determine whole body protein kinetics and net protein balance over 10 and 24 h of recovery. Performance was assessed pre-exercise and at 0, 10, and 24 h of recovery using a battery of tests. Net protein balance tended to improve in PRO ( P = 0.064; effect size (ES) = 0.61, PRO vs. CHO) during overnight recovery. Over 24 h, net balance was enhanced in PRO ( P = 0.036) but not in CHO ( P = 0.84; ES = 0.69, PRO vs. CHO), which was mediated primarily by a reduction in protein breakdown (PRO protein supplementation improved MVC (ES = 0.76), REP (ES = 0.44), and peak power (ES = 0.55). In conclusion, whey protein supplementation enhances whole body anabolism, and may improve acute recovery of exercise performance after a strenuous bout of resistance exercise.

Virtual Sensorimotor Balance Training for Children With Fetal Alcohol Spectrum Disorders: Feasibility Study.

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McCoy, Sarah Westcott; Jirikowic, Tracy; Price, Robert; Ciol, Marcia A; Hsu, Lin-Ya; Dellon, Brian; Kartin, Deborah

2015-11-01

Diminished sensory adaptation has been associated with poor balance control for children with fetal alcohol spectrum disorders (FASD). A virtual reality system, Sensorimotor Training to Affect Balance, Engagement and Learning (STABEL), was developed to train sensory control for balance. The purpose of this study was to examine the STABEL system in children with FASD and children with typical development (TD) to (1) determine the feasibility of the STABEL system and (2) explore the immediate effects of the STABEL system on sensory attention and postural control. This is a technical report with observational study data. Eleven children with FASD and 11 children with TD, aged 8 to 16 years, completed 30 minutes of STABEL training. The children answered questions about their experience using STABEL. Sensory attention and postural control were measured pre- and post-STABEL training with the Multimodal Balance Entrainment Response system and compared using repeated-measures analysis of variance. All children engaged in game play and tolerated controlled sensory input during the STABEL protocol. Immediate effects post-STABEL training in both groups were increased postural sway velocity and some changes in entrainment gain. Children with FASD showed higher entrainment gain to vestibular stimuli. There were no significant changes in sensory attention fractions. The small sample size, dose of STABEL training, and exploratory statistical analyses are study limitations, but findings warrant larger systematic study to examine therapeutic effects. Children completed the training protocol, demonstrating the feasibility of the STABEL system. Differences in postural sway velocity post-STABEL training may have been affected by fatigue, warranting further investigation. Limited immediate effects suggest more practice is needed to affect sensory attention; however, entrainment gain changes suggest the STABEL system provoked vestibular responses during balance practice. © 2015

Engineering of metabolic pathways by artificial enzyme channels

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Marlene ePröschel

2015-10-01

Full Text Available Application of industrial enzymes for production of valuable chemical compounds has greatly benefited from recent developments in Systems and Synthetic Biology. Both, in vivo and in vitro systems have been established, allowing conversion of simple into complex compounds. Metabolic engineering in living cells needs to be balanced which is achieved by controlling gene expression levels, translation, scaffolding, compartmentation and flux control. In vitro applications are often hampered by limited protein stability/half-life and insufficient rates of substrate conversion. To improve stability and catalytic activity, proteins are post-translationally modified and arranged in artificial metabolic channels. Within the review article we will first discuss the supramolecular organization of enzymes in living systems and secondly summarize current and future approaches to design artificial metabolic channels by additive manufacturing for the efficient production of desired products.

Loss of balance during balance beam walking elicits a multifocal theta band electrocortical response.

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Sipp, Amy R; Gwin, Joseph T; Makeig, Scott; Ferris, Daniel P

2013-11-01

Determining the neural correlates of loss of balance during walking could lead to improved clinical assessment and treatment for individuals predisposed to falls. We used high-density electroencephalography (EEG) combined with independent component analysis (ICA) to study loss of balance during human walking. We examined 26 healthy young subjects performing heel-to-toe walking on a treadmill-mounted balance beam as well as walking on the treadmill belt (both at 0.22 m/s). ICA identified clusters of electrocortical EEG sources located in or near anterior cingulate, anterior parietal, superior dorsolateral-prefrontal, and medial sensorimotor cortex that exhibited significantly larger mean spectral power in the theta band (4-7 Hz) during walking on the balance beam compared with treadmill walking. Left and right sensorimotor cortex clusters produced significantly less power in the beta band (12-30 Hz) during walking on the balance beam compared with treadmill walking. For each source cluster, we also computed a normalized mean time/frequency spectrogram time locked to the gait cycle during loss of balance (i.e., when subjects stepped off the balance beam). All clusters except the medial sensorimotor cluster exhibited a transient increase in theta band power during loss of balance. Cluster spectrograms demonstrated that the first electrocortical indication of impending loss of balance occurred in the left sensorimotor cortex at the transition from single support to double support prior to stepping off the beam. These findings provide new insight into the neural correlates of walking balance control and could aid future studies on elderly individuals and others with balance impairments.

Effect of therapeutic horseback riding on balance in community-dwelling older adults with balance deficits.

Science.gov (United States)

Homnick, Douglas N; Henning, Kim M; Swain, Charlene V; Homnick, Tamara D

2013-07-01

Falls are an important cause of morbidity in older adults. Equine-assisted activities including therapeutic riding (TR) benefit balance and neuromuscular control in patients with neurological disabilities but have not been systematically studied in older adults at greater risk for falls due to balance deficits. The effect of an 8-week TR program on measures of balance and quality of life in community-dwelling older adults with established balance deficits was evaluated. This was a pretest-post-test single-group trial of a TR program on measures of balance and quality of life. The study was conducted at a Professional Association of Therapeutic Horsemanship (PATH) International Premier riding center. The subjects comprised 9 adults (5 female, 4 males) with a mean age 76.4 years (range 71-83 years). This included an 8-week observation period followed by an 8-week TR program consisting of 1 hour per week of supervised horseback riding and an 8-week follow-up period. SUBJECTS received balance testing at weeks 0, 8, 16, and 24 using the Fullerton Advanced Balance Scale (FABS), and quality of life was measured at weeks 8 and 16 using the Rand SF (short form) 36 quality-of-life measure. OUTCOME MEASURES were change in the FABS and Rand SF 36. There was no significant difference in balance scores between the start and end of the observation period. There was a significant improvement in the balance score and perception of general health from the start to the end of the intervention period, and no significant difference between the end of the intervention and the end of study, suggesting that improvements may have been sustained. TR is a safe activity for older adults with mild to moderate balance deficits and leads to both improvements in balance and quality of life. Longer and larger studies to assess the benefit of equine-assisted activities on improvements in balance and reduction in fall risk are needed.

Effect of Balance Board Exercises on Balance Tests and Limits of Stability by Biodex Balance System in Normal Men

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Ebrahim Esmaeili

2006-07-01

Full Text Available Objective: Despite tilt-board exercises benefits and its role in ligamentus us injury prevention, little research has been done in this case. The goal of this study is investigation of balance exercises effect for six weeks on balance tests and strength of lower extremity ligaments. Materials & Methods: In present Quasi experimental study, case group was consisted of two 17 subjects groups which did balance exercises for 6 weeks (one group on dominant limb and another on non-dominant limb.Control group did not do any exercise in this period. These groups were evaluated and re-evaluated before and after the exercise period by Biodex Balance System. Results: Statistical analysis revealed significant differences between groups (P<0/05. Conclusion: According to our results it can be concluded that tilt-board exercises can be used as a suitable tool to prevent ligamentus us injuries.

Social jetlag, obesity and metabolic disorder: investigation in a cohort study.

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Parsons, M J; Moffitt, T E; Gregory, A M; Goldman-Mellor, S; Nolan, P M; Poulton, R; Caspi, A

2015-05-01

Obesity is one of the leading causes of preventable death worldwide. Circadian rhythms are known to control both sleep timing and energy homeostasis, and disruptions in circadian rhythms have been linked with metabolic dysfunction and obesity-associated disease. In previous research, social jetlag, a measure of chronic circadian disruption caused by the discrepancy between our internal versus social clocks, was associated with elevated self-reported body mass index, possibly indicative of a more generalized association with obesity and metabolic dysfunction. We studied participants from the population-representative Dunedin Longitudinal Study (N=1037) to determine whether social jetlag was associated with clinically assessed measurements of metabolic phenotypes and disease indicators for obesity-related disease, specifically, indicators of inflammation and diabetes. Our analysis was restricted to N=815 non-shift workers in our cohort. Among these participants, we found that social jetlag was associated with numerous clinically assessed measures of metabolic dysfunction and obesity. We distinguished between obese individuals who were metabolically healthy versus unhealthy, and found higher social jetlag levels in metabolically unhealthy obese individuals. Among metabolically unhealthy obese individuals, social jetlag was additionally associated with elevated glycated hemoglobin and an indicator of inflammation. The findings are consistent with the possibility that 'living against our internal clock' may contribute to metabolic dysfunction and its consequences. Further research aimed at understanding that the physiology and social features of social jetlag may inform obesity prevention and have ramifications for policies and practices that contribute to increased social jetlag, such as work schedules and daylight savings time.

Sensory organisation and reactive balance control of amateur rugby players: A cross-sectional study.

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Chow, Gary C C; Chung, Joanne W Y; Ma, Ada W W; Macfarlane, Duncan J; Fong, Shirley S M

2017-05-01

This study compared the sensory organisation and reactive balance control of amateur rugby players and a control group. Forty-one amateur rugby players (22 males: 19 females; mean height ± SD = 168.8 ± 8.8 cm; mean weight ± SD = 63.9 ± 12.5 kg) and 31 control participants (22 males: 9 females; mean height ± SD = 171.5 ± 10.3 cm; mean weight ± SD = 63.8 ± 10.3 kg) completed the study. Their sensory organisation and standing balance performance were evaluated using a sensory organisation test (SOT), and their reactive balance performance was quantified using a motor control test (MCT). The SOT equilibrium scores (ES) and sensory ratios and the MCT motor response latencies were the major outcome measures. The results revealed that compared to the controls, amateur rugby players had lower SOT ESs under different sensory environments (P rugby group (P = .005, [Formula: see text] = 0.107 and 0.108, respectively). No significant difference was found in the somatosensory ratio (P = .853, [Formula: see text] rugby players demonstrated inferior standing balance performance compared to their non-trained counterparts. They relied less heavily on vestibular and visual inputs to maintain standing balance under different sensory environments. In addition, they reacted more slowly to postural disturbance, reflecting their suboptimal reactive balance ability in standing.

Genome-scale metabolic reconstructions and theoretical investigation of methane conversion in Methylomicrobium buryatense strain 5G(B1).

Science.gov (United States)

de la Torre, Andrea; Metivier, Aisha; Chu, Frances; Laurens, Lieve M L; Beck, David A C; Pienkos, Philip T; Lidstrom, Mary E; Kalyuzhnaya, Marina G

2015-11-25

Methane-utilizing bacteria (methanotrophs) are capable of growth on methane and are attractive systems for bio-catalysis. However, the application of natural methanotrophic strains to large-scale production of value-added chemicals/biofuels requires a number of physiological and genetic alterations. An accurate metabolic model coupled with flux balance analysis can provide a solid interpretative framework for experimental data analyses and integration. A stoichiometric flux balance model of Methylomicrobium buryatense strain 5G(B1) was constructed and used for evaluating metabolic engineering strategies for biofuels and chemical production with a methanotrophic bacterium as the catalytic platform. The initial metabolic reconstruction was based on whole-genome predictions. Each metabolic step was manually verified, gapfilled, and modified in accordance with genome-wide expression data. The final model incorporates a total of 841 reactions (in 167 metabolic pathways). Of these, up to 400 reactions were recruited to produce 118 intracellular metabolites. The flux balance simulations suggest that only the transfer of electrons from methanol oxidation to methane oxidation steps can support measured growth and methane/oxygen consumption parameters, while the scenario employing NADH as a possible source of electrons for particulate methane monooxygenase cannot. Direct coupling between methane oxidation and methanol oxidation accounts for most of the membrane-associated methane monooxygenase activity. However the best fit to experimental results is achieved only after assuming that the efficiency of direct coupling depends on growth conditions and additional NADH input (about 0.1-0.2 mol of incremental NADH per one mol of methane oxidized). The additional input is proposed to cover loss of electrons through inefficiency and to sustain methane oxidation at perturbations or support uphill electron transfer. Finally, the model was used for testing the carbon conversion

Masticatory efficiency contributing to the improved dynamic postural balance: A cross-sectional study.

Science.gov (United States)

Hwang, Hae-Yun; Choi, Jun-Seon; Kim, Hee-Eun

2018-05-28

To evaluate whether masticatory efficiency is associated with dynamic postural balance. Masticatory dysfunction can cause deterioration of general health due to nutritional imbalances, thereby negatively affecting postural balance. However, few studies have investigated the association between masticatory efficiency and postural balance. The masticatory efficiency of 74 participants was evaluated by calculating mixing ability index (MAI) using a wax cube. The timed up and go test (TUGT) was used to measure dynamic balance. Participants with an MAI above or below the median value of 1.05 were defined as having high or low masticatory efficiency, respectively. An independent samples t-test was used to identify significant differences in TUGT, according to masticatory efficiency. Analysis of covariance was performed to adjust for confounding factors. Logistic regression analysis was used to assess the correlation between masticatory efficiency and postural balance. The high masticatory efficiency group could complete the TUGT exercise approximately 1.67 seconds faster while maintaining the postural balance, compared to the low masticatory efficiency group (P = .005). Furthermore, the postural imbalance odds of the group with high mastication efficiency decreased by 0.14-fold, relative to the group with low mastication efficiency (95% confidence interval: 0.04-0.46). With some reservations about statistical power, the association found between masticatory efficiency and postural balance justifies further investigations to confirm the strength of the associations, and possibly to identify causal relationships between mastication and posture in old age. © 2018 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

Unilateral Hearing Loss Is Associated With Impaired Balance in Children: A Pilot Study.

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Wolter, Nikolaus E; Cushing, Sharon L; Vilchez-Madrigal, Luis D; James, Adrian L; Campos, Jennifer; Papsin, Blake C; Gordon, Karen A

2016-12-01

To determine if children with unilateral sensorineural hearing loss (UHL) demonstrate impaired balance compared with their normal hearing (NH) peers. Prospective, case-control study. Balance was assessed in14 UHL and 14 NH children using the Bruininks-Oseretsky Test-2 (BOT-2) and time to fall (TTF) in an immersive, virtual-reality laboratory. Postural control was quantified by center of pressure (COP) using force plates. The effect of vision on balance was assessed by comparing scores and COP characteristics on BOT-2 tasks performed with eyes open and closed. Balance ability as measured by the BOT-2 score was significantly worse in children with UHL compared with NH children (p = 0.004). TTF was shorter in children with UHL compared with NH children in the most difficult tasks when visual and somatosensory inputs were limited (p children with UHL when visual input was removed while performing moderately difficult tasks (i.e., standing on one foot) (p = 0.02). In this pilot study, children with UHL show poorer balance skills than NH children. Significant differences in TTF between the two groups were only seen in the most difficult tasks and therefore may be missed on routine clinical assessment. Children with UHL appear to rely more on vision for maintaining postural control than their NH peers. These findings may point to deficits not only in the hearing but also the vestibular portion of the inner ear.

Prevalence of metabolic syndrome in Middle-East countries: Meta-analysis of cross-sectional studies.

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Ansarimoghaddam, Alireza; Adineh, Hosein Ali; Zareban, Iraj; Iranpour, Sohrab; HosseinZadeh, Ali; Kh, Framanfarma

Metabolic syndrome is an important metabolic disorder which impose noticeable burden on health system. We aimed to review and imply the prevalence of it in Middle-East countries. present study was a systematic review to present overview about metabolic disorder in Middle East. Electronic literature search of Medline database and Google scholar were done for English-language articles without time filtering, as well as for population-based or national studies of the prevalence of metabolic syndrome. The fallowing search terms were used simultaneously: prevalence of " metabolic syndrome" and "national study", "prevalence of metabolic syndrome in Middle East", "prevalence of metabolic syndrome" and "name of country", "metabolic syndrome &name of country". Additionally, relevant articles in bibliography were searched. Analysis of data was carried out in STATA version 11.0. out of 456 studies in first-step searching (selecting by title) 59 studies were recruited and reviewed. Prevalence of metabolic syndrome fluctuated by country and time of study. This amount was 2.2-44% in Turkish, 16-41% in Saudi-Arabia, 14-63 in Pakistan, 26-33 in Qatar, 9-36 in Kuwait, 22-50 in Emirate, 6-42 in Iran, and up to 23 in Yemen. Pooled estimate was 25%. Attributable risk for cardiovascular disease, coronary heart disease, and stroke was 15.87, 11.7, and 16.23, respectively. The prevalence rate of metabolic syndrome is high and it is noticeable cause for stroke, coronary heart disease, and cardiovascular disease. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Effects of a dynamic balance training protocol on podalic support in older women. Pilot Study.

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Battaglia, Giuseppe; Bellafiore, Marianna; Bianco, Antonino; Paoli, Antonio; Palma, Antonio

2010-01-01

The foot provides the only direct contact with supporting surfaces and therefore plays an important role in all postural tasks. Changes in the musculoskeletal and neurological characteristics of the foot with advancing age can alter plantar loading patterns and postural balance. Several studies have reported that exercise training improves postural performance in elderly individuals. The aim of our study was to investigate the effectiveness of a dynamic balance training protocol performed for 5 weeks on the support surface, percentage distribution of load in both feet, and body balance performance in healthy elderly women. Ten subjects (68.67±5.50 yrs old; 28.17±3.35 BMI) were evaluated with a monopodalic performance test and baropodometric analyses before and after the training period. We found a significant improvement in balance unipedal performance times on left and right foot by 20.18% and 26.23% respectively (p0.05). The increased support surface and equal redistribution of body weight on both feet obtained in response to our training protocol may be postural adaptations sufficient to improve static balance in elderly women.

The effect of therapeutic horseback riding on balance in community-dwelling older adults: a pilot study.

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Homnick, Tamara D; Henning, Kim M; Swain, Charlene V; Homnick, Douglas N

2015-02-01

Equine assisted activities (hippotherapy and therapeutic riding) improve balance in patients with disabilities such as cerebral palsy, but have not been systematically studied in older adults, at risk of falls due to balance deficits. We conducted a 10-week, single blind, controlled trial of the effect of a therapeutic horseback riding course on measures of balance in community-dwelling adults 65 years and older. Nine riders and six controls completed the trial. Controls were age matched to riders and all participants were recruited from the local community. Both groups showed improvements in balance during the trial, but did not reach statistical significance. Sample size was small, participants had relatively high initial balance scores, and controls tended to increase their physical activities, likely influencing outcomes. No adverse events occurred and the supervised therapeutic riding program appeared to be a safe and effective form of exercise to improve balance in older adults. A power analysis was performed to estimate numbers of participants needed for a larger study. © The Author(s) 2012.

Glucose Regulates Hypothalamic Long-chain Fatty Acid Metabolism via AMP-activated Kinase (AMPK) in Neurons and Astrocytes*

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Taïb, Bouchra; Bouyakdan, Khalil; Hryhorczuk, Cécile; Rodaros, Demetra; Fulton, Stephanie; Alquier, Thierry

2013-01-01

Hypothalamic controls of energy balance rely on the detection of circulating nutrients such as glucose and long-chain fatty acids (LCFA) by the mediobasal hypothalamus (MBH). LCFA metabolism in the MBH plays a key role in the control of food intake and glucose homeostasis, yet it is not known if glucose regulates LCFA oxidation and esterification in the MBH and, if so, which hypothalamic cell type(s) and intracellular signaling mechanisms are involved. The aim of this study was to determine the impact of glucose on LCFA metabolism, assess the role of AMP-activated Kinase (AMPK), and to establish if changes in LCFA metabolism and its regulation by glucose vary as a function of the kind of LCFA, cell type, and brain region. We show that glucose inhibits palmitate oxidation via AMPK in hypothalamic neuronal cell lines, primary hypothalamic astrocyte cultures, and MBH slices ex vivo but not in cortical astrocytes and slice preparations. In contrast, oleate oxidation was not affected by glucose or AMPK inhibition in MBH slices. In addition, our results show that glucose increases palmitate, but not oleate, esterification into neutral lipids in neurons and MBH slices but not in hypothalamic astrocytes. These findings reveal for the first time the metabolic fate of different LCFA in the MBH, demonstrate AMPK-dependent glucose regulation of LCFA oxidation in both astrocytes and neurons, and establish metabolic coupling of glucose and LCFA as a distinguishing feature of hypothalamic nuclei critical for the control of energy balance. PMID:24240094

The Copper Balance of Cities

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Kral, Ulrich; Lin, Chih-Yi; Kellner, Katharina; Ma, Hwong-wen; Brunner, Paul H

2014-01-01

Material management faces a dual challenge: on the one hand satisfying large and increasing demands for goods and on the other hand accommodating wastes and emissions in sinks. Hence, the characterization of material flows and stocks is relevant for both improving resource efficiency and environmental protection. This article focuses on the urban scale, a dimension rarely investigated in past metal flow studies. We compare the copper (Cu) metabolism of two cities in different economic states, namely, Vienna (Europe) and Taipei (Asia). Substance flow analysis is used to calculate urban Cu balances in a comprehensive and transparent form. The main difference between Cu in the two cities appears to be the stock: Vienna seems close to saturation with 180 kilograms per capita (kg/cap) and a growth rate of 2% per year. In contrast, the Taipei stock of 30 kg/cap grows rapidly by 26% per year. Even though most Cu is recycled in both cities, bottom ash from municipal solid waste incineration represents an unused Cu potential accounting for 1% to 5% of annual demand. Nonpoint emissions are predominant; up to 50% of the loadings into the sewer system are from nonpoint sources. The results of this research are instrumental for the design of the Cu metabolism in each city. The outcomes serve as a base for identification and recovery of recyclables as well as for directing nonrecyclables to appropriate sinks, avoiding sensitive environmental pathways. The methodology applied is well suited for city benchmarking if sufficient data are available. PMID:25866460

Epigenome-wide association study of metabolic syndrome in African-American adults.

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Akinyemiju, Tomi; Do, Anh N; Patki, Amit; Aslibekyan, Stella; Zhi, Degui; Hidalgo, Bertha; Tiwari, Hemant K; Absher, Devin; Geng, Xin; Arnett, Donna K; Irvin, Marguerite R

2018-01-01

The high prevalence of obesity among US adults has resulted in significant increases in associated metabolic disorders such as diabetes, dyslipidemia, and high blood pressure. Together, these disorders constitute metabolic syndrome, a clinically defined condition highly prevalent among African-Americans. Identifying epigenetic alterations associated with metabolic syndrome may provide additional information regarding etiology beyond current evidence from genome-wide association studies. Data on metabolic syndrome and DNA methylation was assessed on 614 African-Americans from the Hypertension Genetic Epidemiology Network (HyperGEN) study. Metabolic syndrome was defined using the joint harmonized criteria, and DNA methylation was assessed using the Illumina HumanMethylation450K Bead Chip assay on DNA extracted from buffy coat. Linear mixed effects regression models were used to examine the association between CpG methylation at > 450,000 CpG sites and metabolic syndrome adjusted for study covariates. Replication using DNA from a separate sample of 69 African-Americans, as well as meta-analysis combining both cohorts, was conducted. Two differentially methylated CpG sites in the IGF2BP1 gene on chromosome 17 (cg06638433; p value = 3.10 × 10 - 7 ) and the ABCG1 gene on chromosome 21 (cg06500161; p value = 2.60 × 10 - 8 ) were identified. Results for the ABCG1 gene remained statistically significant in the replication dataset and meta-analysis. Metabolic syndrome was consistently associated with increased methylation in the ABCG1 gene in the discovery and replication datasets, a gene that encodes a protein in the ATP-binding cassette transporter family and is involved in intra- and extra-cellular signaling and lipid transport.

Energy balance of forage consumption by phyllophagous insects: optimization model

Directory of Open Access Journals (Sweden)

O. V. Tarasova

2015-06-01

Full Text Available The model of optimal food consumption by phytophagous insects proposed, in which the metabolic costs are presented in the form of two components – the cost of food utilization and costs for proper metabolism of the individuals. Two measures were introduced – the «price» of food conversion and the «price» of biomass synthesis of individuals to assess the effectiveness of food consumption by caterpillars. The proposed approach to the description of food consumption by insects provides the exact solutions of the equation of energy balance of food consumption and determining the effectiveness of consumption and the risk of death of the individual. Experiments on larvae’s feeding in laboratory conditions were carried out to verify the model. Caterpillars of Aporia crataegi L. (Lepidoptera, Pieridae were the research subjects. Supply­demand balance, calculated value of the environmental price of consumption and efficiency of food consumption for each individual were determined from experimental data. It was found that the fertility of the female does not depend on the weight of food consumed by it, but is linearly dependent on the food consumption efficiency index. The greater the efficiency of food consumption by an individual, the higher its fertility. The data obtained in the course of experiments on the feeding caterpillars Aporia crataegi were compared with the data presented in the works of other authors and counted in the proposed model of consumption. Calculations allowed estimation of the critical value of food conversion price below which the energy balance is negative and the existence of an individual is not possible.

Uses and limits of radiotracers in the study of drugs and xenobiotics metabolism

International Nuclear Information System (INIS)

Cohen, Y.

1980-01-01

This review deals with scientific papers issued in 1977-1978, on labelling of drugs and xenobiotics and their metabolism. It is divided in five parts: site of label; in vivo metabolism in animals and human beings; in vitro metabolism on tissue slices, cells culture, microsomes, membrane receptors; metabolism of xenobiotics: nutrients, food additives, detergents, plastics and fabrics; discussion. Metabolic studies, nowadays, associate radiotracers, stable isotopes with high performing procedures for analytical separation [fr

Associations Between Adiposity and Metabolic Syndrome Over Time: The Healthy Twin Study.

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Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

2017-04-01

We evaluated the association between changes in adiposity traits including anthropometric and fat mass indicators and changes in metabolic syndrome traits including metabolic syndrome clustering and individual components over time. We also assessed the shared genetic and environmental correlations between the two traits. Participants were 284 South Korean twin individuals and 279 nontwin family members had complete data for changes in adiposity traits and metabolic syndrome traits of the Healthy Twin study. Mixed linear model and bivariate variance-component analysis were applied. Over a period of 3.1 ± 0.6 years of study, changes in adiposity traits [body mass index (BMI), waist circumference, total fat mass, and fat mass to lean mass ratio] had significant associations with changes in metabolic syndrome clustering [high blood pressure, high serum glucose, high triglycerides (TG), and low high-density lipoprotein cholesterol] after adjusting for intra-familial and sibling correlations, age, sex, baseline metabolic syndrome clustering, and socioeconomic factors and health behaviors at follow-up. Change in BMI associated significantly with changes in individual metabolic syndrome components compared to other adiposity traits. Change in metabolic syndrome component TG was a better predictor of changes in adiposity traits compared to changes in other metabolic components. These associations were explained by significant environmental correlations but not by genetic correlations. Changes in anthropometric and fat mass indicators were positively associated with changes in metabolic syndrome clustering and those associations appeared to be regulated by environmental influences.

Qigong improves balance in young women: a pilot study.

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González López-Arza, María Victoria; Varela-Donoso, Enrique; Montanero-Fernández, Jesús; Rodríguez-Mansilla, Juan; González-Sánchez, Blanca; González López-Arza, Luis

2013-07-01

Balance problems are common in people of all ages and can lead to falls, thus causing fractures with consequent disability. Qigong practice has long been part of daily life in Chinese culture, and has good effects on physical health maintenance. The present work describes the change in balance in young, healthy women after practising Qigong for eight weeks. The study took the form of a controlled, randomised longitudinal trial, and involved 30 women aged 18-25 years. The subjects had no prior experience of Qigong or Tai Chi and were unaware of the aims of the study. Subjects were randomly assigned to a Qigong intervention group or a control group. Those in the Qigong intervention group performed "exercises in 20 figures for health and long-life" (Wang Ziping) for 1 h twice per week, for 4 weeks. The control group undertook no exercise at all. The main outcome measure was the stabilometry values. These were obtained in a unipodal support test, using a plantar pressure platform with optical sensors. The Qigong subjects showed a significant improvement in their stabilometry results (40.1% pre-intervention and 56.4% post-intervention) (Pbalance in healthy, young women.

A study on the force balance of an unbalanced globe valve

International Nuclear Information System (INIS)

Yang, Sang Min; Cho, Taik Dong; Ko, Sung Ho; Lee, Ho Young

2007-01-01

A pneumatic control valve is a piping element that controls the volumetric flow rate and pressure of a fluid: it is necessary to analyze the characteristics of the forces with respect to the opening of the valve in order to evaluate its operating performance. The forces occurring during operation are: resisting force and actuator force, where the load resistance is mostly affected by the fluid pressure difference of the valve. In this study, a force balance equation derived from the equilibrium relationship between the resisting force and the actuator force of an unbalanced globe valve is proposed, and the force balance equations are used to model the dynamic equations of a pneumatic unbalanced globe valve installed in nuclear power plants. A CFD analysis is also carried out to evaluate the pressure distribution and forces acting on the top and bottom planes of the valve plug. The results of this analysis have been verified through experimentation. This study has shown that the fluid pressure difference between the inlet and outlet of the valve, measured from the force balance equation of an unbalanced valve, should actually be examined with the fluid-pressure difference between the top and bottom side of the valve plug

Impaired osteoblast function in osteoporosis: comparison between calcium balance and dynamic histomorphometry.

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Arlot, M; Edouard, C; Meunier, P J; Neer, R M; Reeve, J

1984-09-01

Osteoblast function was investigated in 27 patients with idiopathic osteoporosis. Transiliac bone biopsy specimens were taken after double labelling with tetracycline, and metabolic calcium balance was studied almost simultaneously. Many of the patients showed poor double labelling of their otherwise unremarkable trabecular osteoid, suggesting impaired formation of bone at many of these surfaces. This phenomenon was not accompanied by increased width of osteoid seams (as seen in osteomalacia), indicating that formation of the matrix and its mineralisation were in equilibrium. For the first time, highly significant positive correlations (p less than 0.01) were found between indices of bone formation, determined by labelling with tetracycline, and calcium balance. Thus some patients with osteoporosis who are rapidly losing bone have low rates of formation of trabecular bone both by individual osteoblasts and in relation to available bone surfaces. As histological indices of bone resorption also independently correlated strongly and inversely (p less than 0.01) with calcium balance the rate of initiation of new basic multicellular units by osteoclastic resorption of trabecular surfaces (or the depth of resorption at these surfaces) also appears to be an important determinant of mineral balance. The mechanisms that regulate the effective life span of mature osteoblasts require further investigation, particularly as some promising treatments that can increase trabecular bone volume in osteoporosis, such as parathyroid peptide hPTH (1-34) and sodium fluoride, must work through a reversal of osteoblastic depression.

Fulfillment of Work–Life Balance From the Organizational Perspective: A Case Study

Science.gov (United States)

Mazerolle, Stephanie M.; Goodman, Ashley

2013-01-01

Context: Researchers studying work–life balance have examined policy development and implementation to create a family-friendly work environment from an individualistic perspective rather than from a cohort of employees working under the same supervisor. Objective: To investigate what factors influence work–life balance within the National Collegiate Athletic Association (NCAA) Division I clinical setting from the perspective of an athletic training staff. Design: Qualitative study. Setting: Web-based management system. Patients or Other Participants: Eight athletic trainers (5 men, 3 women; age = 38 ± 7 years) in the NCAA Division I setting. Data Collection and Analysis: Participants responded to a series of questions by journaling their thoughts and experiences. We included data-source triangulation, multiple-analyst triangulation, and peer review to establish data credibility. We analyzed the data via a grounded theory approach. Results: Three themes emerged from the data. Family-oriented and supportive work environment was described as a workplace that fosters and encourages work–life balance through professionally and personally shared goals. Nonwork outlets included activities, such as exercise and personal hobbies, that provide time away from the role of the athletic trainer. Individualistic strategies reflected that although the athletic training staff must work together and support one another, each staff member must have his or her own personal strategies to manage personal and professional responsibilities. Conclusions: The foundation for a successful work environment in the NCAA Division I clinical setting potentially can center on the management style of the supervisor, especially one who promotes teamwork among his or her staff members. Although a family-friendly work environment is necessary for work–life balance, each member of the athletic training staff must have personal strategies in place to fully achieve a balance. PMID:24067152

Validation of the Balance Board for Clinical Evaluation of Balance During Serious Gaming Rehabilitation Exercises.

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Bonnechère, Bruno; Jansen, Bart; Omelina, Lubos; Sholukha, Victor; Van Sint Jan, Serge

2016-09-01

Balance and posture can be affected in various conditions or become decreased with aging. A diminution of balance control induces an increase of fall's risk. The Nintendo Wii Balance Board™ (WBB) is used in rehabilitation to perform balance exercises (using commercial video games). The WBB has also been validated to assess balance and posture in static conditions. However, there is currently no study investigating the use of WBB to assess balance during the realization of balance exercises using this device. The aim of this study was to validate the use of WBB, coupled with specially developed serious games, to assess dynamic balance during rehabilitation exercises. Thirty five subjects participated in this study. Subjects were asked to play two specially developed serious games. Center of pressure (CP) displacements were simultaneously recorded with a WBB and a gold standard force plate (FP). Nine parameters were derived from CP displacement. Bland and Altman plots, paired-sample t tests, intraclass correlation coefficient's, and Pearson's coefficient correlations were computed. Excellent correlation between both devices was found for each parameter for the two games (R = 0.95 and 0.96). Unlike previous work on the WBB, these excellent results were obtained without using any calibration procedure. Despite this, results were highly correlated between the WBB and the FP. The WBB could be used in clinics to assess balance during rehabilitation exercises and, thus, allows a more regular patient follow-up.

Altered erythropoiesis and iron metabolism in carriers of thalassemia

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Guimarães, Jacqueline S.; Cominal, Juçara G.; Silva-Pinto, Ana Cristina; Olbina, Gordana; Ginzburg, Yelena Z.; Nandi, Vijay; Westerman, Mark; Rivella, Stefano; de Souza, Ana Maria

2014-01-01

The thalassemia syndromes (α- and β-thalassemia) are the most common and frequent disorders associated with ineffective erythropoiesis. Imbalance of α- or β-globin chain production results in impaired red blood cell synthesis, anemia and more erythroid progenitors in the blood stream. While patients affected by these disorders show definitive altered parameters related to erythropoiesis, the relationship between the degree of anemia, altered erythropoiesis and dysfunctional iron metabolism have not been investigated in both α-thalassemia carriers (ATC) and β-thalassemia carriers (BTC). Here we demonstrate that ATC have a significantly reduced hepcidin and increased soluble transferrin receptor levels but relatively normal hematological findings. In contrast, BTC have several hematological parameters significantly different from controls, including increased soluble transferrin receptor and erythropoietin levels. These changings in both groups suggest an altered balance between erythropoiesis and iron metabolism. The index sTfR/log ferrin and (hepcidin/ferritin)/sTfR are respectively increased and reduced relative to controls, proportional to the severity of each thalassemia group. In conclusion, we showed in this study, for the first time in the literature, that thalassemia carriers have altered iron metabolism and erythropoiesis. PMID:25307880

The traditional Korean dietary pattern is associated with decreased risk of metabolic syndrome: findings from the Korean National Health and Nutrition Examination Survey, 1998-2009.

Science.gov (United States)

Lee, Kyung Won; Cho, Mi Sook

2014-01-01

The traditional Korean diet has several healthy components, including abundant vegetables, fermented foods, a variety of foodstuffs, and a balance of animal and vegetable food intake. Although the traditional Korean diet has many healthy components, few studies have been conducted on the health advantages of the Korean dietary pattern. This study is intended to clarify the relationship between Korean dietary patterns and chronic diseases using the Integrated Korean Dietary Pattern Score (I-KDPS). I-KDPS is an index for measuring Korean dietary patterns based on traditional Korean meals and reflects the complex and multifaceted characteristics of Korean food culture. I-KDPS is composed of seven items to measure the level of balance and adequacy of Korean food consumption, with a maximum score of 60. When I-KDPS was applied to the Korean National Health and Nutrition Examination Survey (1998-2009), a nationwide survey, I-KDPS was closely related to the risk of metabolic syndrome. Even though there were a few differences among the years surveyed, the risk of metabolic syndrome, obesity, hypertension, and hypertriglyceridemia significantly decreased as I-KDPS increased. These results indicate that risk of diseases, including metabolic syndrome, decreases in individuals adhering to traditional Korean dietary patterns in adequate levels and those who eat a balanced diet. The result of this study shows that the traditional Korean table setting, which comprises side dishes, including seasoned vegetables, grilled dishes, and fermented products with cooked rice (bap), soup (guk), and kimchi, contains traits that help prevent metabolic syndrome. I-KDPS coupled with the basic study of the healthfulness of the Korean dietary lifestyle is expected to help establish a foundation for continuous development of health promoting Korean foods and dietary culture.

Applications of computational modeling in metabolic engineering of yeast.

Science.gov (United States)

Kerkhoven, Eduard J; Lahtvee, Petri-Jaan; Nielsen, Jens

2015-02-01

Generally, a microorganism's phenotype can be described by its pattern of metabolic fluxes. Although fluxes cannot be measured directly, inference of fluxes is well established. In biotechnology the aim is often to increase the capacity of specific fluxes. For this, metabolic engineering methods have been developed and applied extensively. Many of these rely on balancing of intracellular metabolites, redox, and energy fluxes, using genome-scale models (GEMs) that in combination with appropriate objective functions and constraints can be used to predict potential gene targets for obtaining a preferred flux distribution. These methods point to strategies for altering gene expression; however, fluxes are often controlled by post-transcriptional events. Moreover, GEMs are usually not taking into account metabolic regulation, thermodynamics and enzyme kinetics. To facilitate metabolic engineering, tools from synthetic biology have emerged, enabling integration and assembly of naturally nonexistent, but well-characterized components into a living organism. To describe these systems kinetic models are often used and to integrate these systems with the standard metabolic engineering approach, it is necessary to expand the modeling of metabolism to consider kinetics of individual processes. This review will give an overview about models available for metabolic engineering of yeast and discusses their applications. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

Studies with nitrogen-15-labelled amino acids for a quantitative description of nitrogen metabolism in man

International Nuclear Information System (INIS)

Hartig, W.; Faust, H.; Czarnetzki, H.D.; Winkler, E.; Akademie der Wissenschaften der DDR, Leipzig. Zentralinstitut fuer Isotopen- und Strahlenforschung)

1977-01-01

The utilization of glycine in healthy and stressed persons has been studied by continuous infusion or oral administration. The results of our studies show that (1) Breakdown of protein is increased in stress conditions; (2) Amino acids are also synthesized to protein in stress, the percentage of amino acids used for synthesis being smaller in stress conditions; (3) The urea synthesis during stress is increased and accelerated; (4) In the isotopic steady state 23% of the 15 N-glycine administered by infusion to healthy persons and 41% of the amount administered to patients after cholecystectomy is eliminated (urea 16%/26%; ammonia 4%/5%); using a single oral dose 24% is eliminated as total N after 24h (19% as 15 N-urea and 4% as 15 N-ammonia); (5) Depending on the method of gastric surgery the absorption and elimination rate of glycine-N varied; the more rapid intestinal absorption of glycine in comparison with healthy persons leads to a higher 15 N elimination via urine, and causes a disturbance of the nitrogen metabolism and nitrogen balance. (author)

Effect of dietary energy source on energy balance, production, metabolic disorders and reproduction in lactating dairy cattle

NARCIS (Netherlands)

Knegsel, van A.T.M.; Brand, van den H.; Dijkstra, J.; Tamminga, S.; Kemp, B.

2005-01-01

The pathway for oxidation of energy involves a balanced oxidation of C2 and C3 compounds. During early lactation in dairy cattle this C2/C3 ratio is out of balance, due to a high availability of lipogenic (C2) products and a low availability of glycogenic (C3) products relative of the C2 and C3

Regulation of Liver Energy Balance by the Nuclear Receptors Farnesoid X Receptor and Peroxisome Proliferator Activated Receptor α.

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Kim, Kang Ho; Moore, David D

2017-01-01

The liver undergoes major changes in substrate utilization and metabolic output over the daily feeding and fasting cycle. These changes occur acutely in response to hormones such as insulin and glucagon, with rapid changes in signaling pathways mediated by protein phosphorylation and other post-translational modifications. They are also reflected in chronic alterations in gene expression in response to nutrient-sensitive transcription factors. Among these, the nuclear receptors farnesoid X receptor (FXR) and peroxisome proliferator activated receptor α (PPARα) provide an intriguing, coordinated response to maintain energy balance in the liver. FXR is activated in the fed state by bile acids returning to the liver, while PPARα is activated in the fasted state in response to the free fatty acids produced by adipocyte lipolysis or possibly other signals. Key Messages: Previous studies indicate that FXR and PPARα have opposing effects on each other's primary targets in key metabolic pathways including gluconeogenesis. Our more recent work shows that these 2 nuclear receptors coordinately regulate autophagy: FXR suppresses this pathway of nutrient and energy recovery, while PPARα activates it. Another recent study indicates that FXR activates the complement and coagulation pathway, while earlier studies identify this as a negative target of PPARα. Since secretion is a very energy- and nutrient-intensive process for hepatocytes, it is possible that FXR licenses it in the nutrient-rich fed state, while PPARα represses it to spare resources in the fasted state. Energy balance is a potential connection linking FXR and PPARα regulation of autophagy and secretion, 2 seemingly unrelated aspects of hepatocyte function. FXR and PPARα act coordinately to promote energy balance and homeostasis in the liver by regulating autophagy and potentially protein secretion. It is quite likely that their impact extends to additional pathways relevant to hepatic energy balance, and

Improvements in balance control in individuals with PCS detected following vestibular training: A case study.

Science.gov (United States)