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Sample records for replenish glycogen stores

  1. Muscle glycogen stores and fatigue

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Westerblad, Håkan; Nielsen, Joachim

    2013-01-01

      Studies performed at the beginning of the last century revealed the importance of carbohydrate as a fuel during exercise, and the importance of muscle glycogen on performance has subsequently been confirmed in numerous studies. However, the link between glycogen depletion and impaired muscle...... function during fatigue is not well understood and a direct cause-and-effect relationship between glycogen and muscle function remains to be established. The use of electron microscopy has revealed that glycogen is not homogeneously distributed in skeletal muscle fibres, but rather localized in distinct...... pools. Furthermore, each glycogen granule has its own metabolic machinery with glycolytic enzymes and regulating proteins. One pool of such glycogenolytic complexes is localized within the myofibrils in close contact with key proteins involved in the excitation-contraction coupling and Ca2+ release from...

  2. Regulation of glycogen synthesis in rat skeletal muscle after glycogen-depleting contractile activity: effects of adrenaline on glycogen synthesis and activation of glycogen synthase and glycogen phosphorylase.

    OpenAIRE

    Franch, J; Aslesen, R; Jensen, J

    1999-01-01

    We investigated the effects of insulin and adrenaline on the rate of glycogen synthesis in skeletal muscles after electrical stimulation in vitro. The contractile activity decreased the glycogen concentration by 62%. After contractile activity, the glycogen stores were fully replenished at a constant and high rate for 3 h when 10 m-i.u./ml insulin was present. In the absence of insulin, only 65% of the initial glycogen stores was replenished. Adrenaline decreased insulin-stimulated glycogen s...

  3. THE EFFECT OF INSULIN AND CARBOHYDRATE SUPPLEMENTATION ON GLYCOGEN REPLENISHMENT AMONG DIFFERENT HINDLIMB MUSCLES IN RATS FOLLOWING PROLONGED SWIMMING

    Directory of Open Access Journals (Sweden)

    Mei-Chich Hsu

    2012-04-01

    Full Text Available In the present study we investigated the interactive effects of insulin and carbohydrate on glycogen replenishment in different rat hindlimb muscles. Forty male Sprague Dawley rats were assigned to 5 groups, including 1 sedentary control with carbohydrate supplement (2 g glucose · kg body wt-1, 2 sedentary rats with 16 hours recovery, carbohydrate and insulin (0.5 U · kg body wt-1, 3 swimming without recovery, 4 swimming with 16 hours recovery and carbohydrate supplement, and 5 swimming with 16 hours recovery, carbohydrate and insulin. The swimming protocol consisted of two 3 h swimming sections, which were separated by a 45 min rest. The insulin and carbohydrate were administered to the rats immediately after exercise. At the end of the experiment, the soleus (S, plantaris (P, quadriceps (Q and gastrocnemius (G were surgically excised to evaluate glycogen utilization and replenishment. We observed that glycogen utilization was significantly lower in G and Q than S and P during swimming (p <0.05, and S showed the greatest capacity of glycogen resynthesis after post-exercise recovery (p <0.05. In the sedentary state, the glycogen synthesis did not differ among hindlimb muscles during insulin and carbohydrate treatments. Interestingly, with insulin and carbohydrate, the glycogen resynthesis in S and P were significantly greater than in Q and G following post-exercise recovery (p <0.05. We therefore concluded that the soleus and plantaris are the primary working muscles during swimming, and the greatest glycogen replenishment capacity of the soleus during post-exercise recovery is likely due to its highest insulin sensitivity.

  4. Body mass dependence of glycogen stores in the anoxia-tolerant crucian carp ( Carassius carassius L.)

    Science.gov (United States)

    Vornanen, Matti; Asikainen, Juha; Haverinen, Jaakko

    2011-03-01

    Glycogen is a vital energy substrate for anaerobic organisms, and the size of glycogen stores can be a limiting factor for anoxia tolerance of animals. To this end, glycogen stores in 12 different tissues of the crucian carp ( Carassius carassius L.), an anoxia-tolerant fish species, were examined. Glycogen content of different tissues was 2-10 times higher in winter (0.68-18.20% of tissue wet weight) than in summer (0.12-4.23%). In scale, bone and brain glycogen stores were strongly dependent on body mass (range between 0.6 and 785 g), small fish having significantly more glycogen than large fish ( p glycogen reserves, measured as a sum of glycogen from different tissues, varied from 6.1% of the body mass in the 1-g fish to 2.0% in the 800-g fish. Since anaerobic metabolic rate scales down with body size, the whole body glycogen reserves could provide energy for approximately 79 and 88 days of anoxia in small and large fish, respectively. There was, however, a drastic difference in tissue distribution of glycogen between large and small fish: in the small fish, the liver was the major glycogen store (68% of the stores), while in the large fish, the white myotomal muscle was the principal deposit of glycogen (57%). Since muscle glycogen is considered to be unavailable for blood glucose regulation, its usefulness in anoxia tolerance of the large crucian carp might be limited, although not excluded. Therefore, mobilization of muscle glycogen under anoxia needs to be rigorously tested.

  5. Metabolic demands and replenishment of muscle glycogen after a rugby league match simulation protocol.

    Science.gov (United States)

    Bradley, Warren J; Hannon, Marcus P; Benford, Victoria; Morehen, James C; Twist, Craig; Shepherd, Sam; Cocks, Matthew; Impey, Samuel G; Cooper, Robert G; Morton, James P; Close, Graeme L

    2017-09-01

    The metabolic requirements of a rugby league match simulation protocol and the timing of carbohydrate provision on glycogen re-synthesis in damaged muscle were examined. Fifteen (mean±SD: age 20.9±2.9 year, body-mass 87.3±14.1kg, height 177.4±6.0cm) rugby league (RL) players consumed a 6gkgday-1 CHO diet for 7-days, completed a time to exhaustion test (TTE) and a glycogen depletion protocol on day-3, a RL simulated-match protocol (RLMSP) on day-5 and a TTE on day-7. Players were prescribed an immediate or delayed (2-h-post) re-feed post-simulation. Muscle biopsies and blood samples were obtained post-depletion, before and after simulated match-play, and 48-h after match-play with PlayerLoad and heart-rate collected throughout the simulation. Data were analysed using effects sizes±90% CI and magnitude-based inferences. PlayerLoad (8.0±0.7 AUmin-1) and %HRpeak (83±4.9%) during the simulation were similar to values reported for RL match-play. Muscle glycogen very likely increased from immediately after to 48-h post-simulation (272±97 cf. 416±162mmolkg-1d.w.; ES±90%CI) after immediate re-feed, but changes were unclear (283±68 cf. 361±144mmolkg-1d.w.; ES±90%CI) after delayed re-feed. CK almost certainly increased by 77.9±25.4% (0.75±0.19) post-simulation for all players. The RLMSP presents a replication of the internal loads associated with professional RL match-play, although difficulties in replicating the collision reduced the metabolic demands and glycogen utilisation. Further, it is possible to replete muscle glycogen in damaged muscle employing an immediate re-feed strategy. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. DDeveloping and solving a bi-objective joint replenishment problem under storing space constraint

    Directory of Open Access Journals (Sweden)

    ommolbanin yousefi

    2011-03-01

    Full Text Available In this research, a bi-objective joint replenishment problem has been developed and solved with the assumption of one restricted resource. The proposed model has a storing space constraint and tries to optimize two objective functions simultaneously. They include minimizing annual holding and setup costs and minimizing annual inventory investment. Then, for solving this problem, a multi-objective genetic algorithm (MOGA has been developed. In order to analyze the algorithm efficiency, its performance has been examined in solving 1600 randomly produced problems using parameters extracted from literature. The findings imply that the proposed algorithm is capable of producing a good set of Pareto optimal solutions. Finally, the application of the problem solving approach and the findings of the proposed algorithm have been illustrated for a special problem, which has been randomly produced.

  7. FLCN and AMPK Confer Resistance to Hyperosmotic Stress via Remodeling of Glycogen Stores.

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    Elite Possik

    2015-10-01

    Full Text Available Mechanisms of adaptation to environmental changes in osmolarity are fundamental for cellular and organismal survival. Here we identify a novel osmotic stress resistance pathway in Caenorhabditis elegans (C. elegans, which is dependent on the metabolic master regulator 5'-AMP-activated protein kinase (AMPK and its negative regulator Folliculin (FLCN. FLCN-1 is the nematode ortholog of the tumor suppressor FLCN, responsible for the Birt-Hogg-Dubé (BHD tumor syndrome. We show that flcn-1 mutants exhibit increased resistance to hyperosmotic stress via constitutive AMPK-dependent accumulation of glycogen reserves. Upon hyperosmotic stress exposure, glycogen stores are rapidly degraded, leading to a significant accumulation of the organic osmolyte glycerol through transcriptional upregulation of glycerol-3-phosphate dehydrogenase enzymes (gpdh-1 and gpdh-2. Importantly, the hyperosmotic stress resistance in flcn-1 mutant and wild-type animals is strongly suppressed by loss of AMPK, glycogen synthase, glycogen phosphorylase, or simultaneous loss of gpdh-1 and gpdh-2 enzymes. Our studies show for the first time that animals normally exhibit AMPK-dependent glycogen stores, which can be utilized for rapid adaptation to either energy stress or hyperosmotic stress. Importantly, we show that glycogen accumulates in kidneys from mice lacking FLCN and in renal tumors from a BHD patient. Our findings suggest a dual role for glycogen, acting as a reservoir for energy supply and osmolyte production, and both processes might be supporting tumorigenesis.

  8. Glycogen metabolism and the homeostatic regulation of sleep

    KAUST Repository

    Petit, Jean-Marie; Burlet-Godinot, Sophie; Magistretti, Pierre J.; Allaman, Igor

    2014-01-01

    In 1995 Benington and Heller formulated an energy hypothesis of sleep centered on a key role of glycogen. It was postulated that a major function of sleep is to replenish glycogen stores in the brain that have been depleted during wakefulness which

  9. Pyruvate incubation enhances glycogen stores and sustains neuronal function during subsequent glucose deprivation.

    Science.gov (United States)

    Shetty, Pavan K; Sadgrove, Matthew P; Galeffi, Francesca; Turner, Dennis A

    2012-01-01

    The use of energy substrates, such as lactate and pyruvate, has been shown to improve synaptic function when administered during glucose deprivation. In the present study, we investigated whether prolonged incubation with monocarboxylate (pyruvate or lactate) prior rather than during glucose deprivation can also sustain synaptic and metabolic function. Pyruvate pre-incubation(3-4h) significantly prolonged (>25 min) the tolerance of rat hippocampal slices to delayed glucose deprivation compared to control and lactate pre-incubated slices, as revealed by field excitatory post synaptic potentials (fEPSPs); pre-incubation with pyruvate also reduced the marked decrease in NAD(P)H fluorescence resulting from glucose deprivation. Moreover, pyruvate exposure led to the enhancement of glycogen stores with time, compared to glucose alone (12 μmol/g tissue at 4h vs. 3.5 μmol/g tissue). Prolonged resistance to glucose deprivation following exogenous pyruvate incubation was prevented by glycogenolysis inhibitors, suggesting that enhanced glycogen mediates the delay in synaptic activity failure. The application of an adenosine A1 receptor antagonist enhanced glycogen utilization and prolonged the time to synaptic failure, further confirming this hypothesis of the importance of glycogen. Moreover, tissue levels of ATP were also significantly maintained during glucose deprivation in pyruvate pretreated slices compared to control and lactate. In summary, these experiments indicate that pyruvate exposure prior to glucose deprivation significantly increased the energy buffering capacity of hippocampal slices, particularly by enhancing internal glycogen stores, delaying synaptic failure during glucose deprivation by maintaining ATP levels, and minimizing the decrease in the levels of NAD(P)H. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Muscle glycogen synthesis before and after exercise.

    Science.gov (United States)

    Ivy, J L

    1991-01-01

    The importance of carbohydrates as a fuel source during endurance exercise has been known for 60 years. With the advent of the muscle biopsy needle in the 1960s, it was determined that the major source of carbohydrate during exercise was the muscle glycogen stores. It was demonstrated that the capacity to exercise at intensities between 65 to 75% VO2max was related to the pre-exercise level of muscle glycogen, i.e. the greater the muscle glycogen stores, the longer the exercise time to exhaustion. Because of the paramount importance of muscle glycogen during prolonged, intense exercise, a considerable amount of research has been conducted in an attempt to design the best regimen to elevate the muscle's glycogen stores prior to competition and to determine the most effective means of rapidly replenishing the muscle glycogen stores after exercise. The rate-limiting step in glycogen synthesis is the transfer of glucose from uridine diphosphate-glucose to an amylose chain. This reaction is catalysed by the enzyme glycogen synthase which can exist in a glucose-6-phosphate-dependent, inactive form (D-form) and a glucose-6-phosphate-independent, active form (I-form). The conversion of glycogen synthase from one form to the other is controlled by phosphorylation-dephosphorylation reactions. The muscle glycogen concentration can vary greatly depending on training status, exercise routines and diet. The pattern of muscle glycogen resynthesis following exercise-induced depletion is biphasic. Following the cessation of exercise and with adequate carbohydrate consumption, muscle glycogen is rapidly resynthesised to near pre-exercise levels within 24 hours. Muscle glycogen then increases very gradually to above-normal levels over the next few days. Contributing to the rapid phase of glycogen resynthesis is an increase in the percentage of glycogen synthase I, an increase in the muscle cell membrane permeability to glucose, and an increase in the muscle's sensitivity to insulin

  11. Glycogen dynamics of crucian carp (Carassius carassius) in prolonged anoxia.

    Science.gov (United States)

    Vornanen, Matti; Haverinen, Jaakko

    2016-12-01

    Mobilization of glycogen stores was examined in the anoxic crucian carp (Carassius carassius Linnaeus). Winter-acclimatized fish were exposed to anoxia for 1, 3, or 6 weeks at 2 °C, and changes in the size of glycogen deposits were followed. After 1 week of anoxia, a major part of the glycogen stores was mobilized in liver (79.5 %) and heart (75.6 %), and large decreases occurred in gill (46.7 %) and muscle (45.1 %). Brain was an exception in that its glycogen content remained unchanged. The amount of glycogen degraded during the first anoxic week was sufficient for the anaerobic ethanol production for more than 6 weeks of anoxia. After 3 and 6 weeks of anoxia, there was little further degradation of glycogen in other tissues except the brain where the stores were reduced by 30.1 and 49.9 % after 3 and 6 weeks of anoxia, respectively. One week of normoxic recovery following the 6-week anoxia was associated with a complete replenishment of the brain glycogen and partial recovery of liver, heart, and gill glycogen stores. Notably, the resynthesis of glycogen occurred at the expense of the existing energy reserves of the body in fasting fish. These findings indicate that in crucian carp, glycogen stores are quickly mobilized after the onset of anoxia, with the exception of the brain whose glycogen stores may be saved for putative emergency situations.

  12. POST-EXERCISE MUSCLE GLYCOGEN REPLETION IN THE EXTREME: EFFECT OF FOOD ABSENCE AND ACTIVE RECOVERY

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    Paul A. Fournier

    2004-09-01

    Full Text Available Glycogen plays a major role in supporting the energy demands of skeletal muscles during high intensity exercise. Despite its importance, the amount of glycogen stored in skeletal muscles is so small that a large fraction of it can be depleted in response to a single bout of high intensity exercise. For this reason, it is generally recommended to ingest food after exercise to replenish rapidly muscle glycogen stores, otherwise one's ability to engage in high intensity activity might be compromised. But what if food is not available? It is now well established that, even in the absence of food intake, skeletal muscles have the capacity to replenish some of their glycogen at the expense of endogenous carbon sources such as lactate. This is facilitated, in part, by the transient dephosphorylation-mediated activation of glycogen synthase and inhibition of glycogen phosphorylase. There is also evidence that muscle glycogen synthesis occurs even under conditions conducive to an increased oxidation of lactate post-exercise, such as during active recovery from high intensity exercise. Indeed, although during active recovery glycogen resynthesis is impaired in skeletal muscle as a whole because of increased lactate oxidation, muscle glycogen stores are replenished in Type IIa and IIb fibers while being broken down in Type I fibers of active muscles. This unique ability of Type II fibers to replenish their glycogen stores during exercise should not come as a surprise given the advantages in maintaining adequate muscle glycogen stores in those fibers that play a major role in fight or flight responses

  13. Enzymatic regulation of seasonal glycogen cycling in the freeze-tolerant wood frog, Rana sylvatica.

    Science.gov (United States)

    do Amaral, M Clara F; Lee, Richard E; Costanzo, Jon P

    2016-12-01

    Liver glycogen is an important energy store in vertebrates, and in the freeze-tolerant wood frog, Rana sylvatica, this carbohydrate also serves as a major source of the cryoprotectant glucose. We investigated how variation in the levels of the catalytic subunit of protein kinase A (PKAc), glycogen phosphorylase (GP), and glycogen synthase (GS) relates to seasonal glycogen cycling in a temperate (Ohioan) and subarctic (Alaskan) populations of this species. In spring, Ohioan frogs had reduced potential for glycogen synthesis, as evidenced by low GS activity and high PKAc protein levels. In addition, glycogen levels in spring were the lowest of four seasonal samples, as energy input was likely directed towards metabolism and somatic growth during this period. Near-maximal glycogen levels were reached by mid-summer, and remained unchanged in fall and winter, suggesting that glycogenesis was curtailed during this period. Ohioan frogs had a high potential for glycogenolysis and glycogenesis in winter, as evidenced by large glycogen reserves, high levels of GP and GS proteins, and high GS activity, which likely allows for rapid mobilization of cryoprotectant during freezing and replenishing of glycogen reserves during thawing. Alaskan frogs also achieved a near-maximal liver glycogen concentration by summer and displayed high glycogenic and glycogenolytic potential in winter, but, unlike Ohioan frogs, started replenishing their energy reserves early in spring. We conclude that variation in levels of both glycogenolytic and glycogenic enzymes likely happens in response to seasonal changes in energetic strategies and demands, with winter survival being a key component to understanding the regulation of glycogen cycling in this species.

  14. An optimized histochemical method to assess skeletal muscle glycogen and lipid stores reveals two metabolically distinct populations of type I muscle fibers

    DEFF Research Database (Denmark)

    Prats Gavalda, Clara; Gomez-Cabello, Alba; Nordby, Pernille

    2013-01-01

    Skeletal muscle energy metabolism has been a research focus of physiologists for more than a century. Yet, how the use of intramuscular carbohydrate and lipid energy stores are coordinated during different types of exercise remains a subject of debate. Controversy arises from contradicting data...... preservation of muscle energy stores, air drying cryosections or cycles of freezing-thawing need to be avoided. Furthermore, optimization of the imaging settings in order to specifically image intracellular lipid droplets stained with oil red O or Bodipy-493/503 is shown. When co-staining lipid droplets...... distinct myosin heavy chain I expressing fibers: I-1 fibers have a smaller crossectional area, a higher density of lipid droplets, and a tendency to lower glycogen content compared to I-2 fibers. Type I-2 fibers have similar lipid content than IIA. Exhaustive exercise lead to glycogen depletion in type IIA...

  15. Glycogen metabolism in humans

    OpenAIRE

    Adeva-Andany, María M.; González-Lucán, Manuel; Donapetry-García, Cristóbal; Fernández-Fernández, Carlos; Ameneiros-Rodríguez, Eva

    2016-01-01

    In the human body, glycogen is a branched polymer of glucose stored mainly in the liver and the skeletal muscle that supplies glucose to the blood stream during fasting periods and to the muscle cells during muscle contraction. Glycogen has been identified in other tissues such as brain, heart, kidney, adipose tissue, and erythrocytes, but glycogen function in these tissues is mostly unknown. Glycogen synthesis requires a series of reactions that include glucose entrance into the cell through...

  16. The role of glycogen synthase in the development of hyperglycemia in type 2 diabetes - 'To store or not to store glucose, that's the question'

    DEFF Research Database (Denmark)

    Beck-Nielsen, Henning

    2012-01-01

    This review deals with the role of glycogen storage in skeletal muscle for the development of insulin resistance and type 2 diabetes. Specifically, the role of the enzyme glycogen synthase, which seems to be locked in its hyperphosphorylated and inactivated state, is discussed. This defect seems ...... to be secondary to ectopic lipid disposition in the muscle cells. These molecular defects are discussed in the context of the overall pathophysiology of hyperglycemia in type 2 diabetic subjects. Copyright © 2012 John Wiley & Sons, Ltd....

  17. Glycogen metabolism and the homeostatic regulation of sleep

    KAUST Repository

    Petit, Jean-Marie

    2014-11-16

    In 1995 Benington and Heller formulated an energy hypothesis of sleep centered on a key role of glycogen. It was postulated that a major function of sleep is to replenish glycogen stores in the brain that have been depleted during wakefulness which is associated to an increased energy demand. Astrocytic glycogen depletion participates to an increase of extracellular adenosine release which influences sleep homeostasis. Here, we will review some evidence obtained by studies addressing the question of a key role played by glycogen metabolism in sleep regulation as proposed by this hypothesis or by an alternative hypothesis named “glycogenetic” hypothesis as well as the importance of the confounding effect of glucocorticoïds. Even though actual collected data argue in favor of a role of sleep in brain energy balance-homeostasis, they do not support a critical and direct involvement of glycogen metabolism on sleep regulation. For instance, glycogen levels during the sleep-wake cycle are driven by different physiological signals and therefore appear more as a marker-integrator of brain energy status than a direct regulator of sleep homeostasis. In support of this we provide evidence that blockade of glycogen mobilization does not induce more sleep episodes during the active period while locomotor activity is reduced. These observations do not invalidate the energy hypothesis of sleep but indicate that underlying cellular mechanisms are more complex than postulated by Benington and Heller.

  18. Brain glycogen

    DEFF Research Database (Denmark)

    Obel, Linea Lykke Frimodt; Müller, Margit S; Walls, Anne B

    2012-01-01

    Glycogen is a complex glucose polymer found in a variety of tissues, including brain, where it is localized primarily in astrocytes. The small quantity found in brain compared to e.g., liver has led to the understanding that brain glycogen is merely used during hypoglycemia or ischemia....... In this review evidence is brought forward highlighting what has been an emerging understanding in brain energy metabolism: that glycogen is more than just a convenient way to store energy for use in emergencies-it is a highly dynamic molecule with versatile implications in brain function, i.e., synaptic...... activity and memory formation. In line with the great spatiotemporal complexity of the brain and thereof derived focus on the basis for ensuring the availability of the right amount of energy at the right time and place, we here encourage a closer look into the molecular and subcellular mechanisms...

  19. Hexokinase 2, glycogen synthase and phosphorylase play a key role in muscle glycogen supercompensation

    DEFF Research Database (Denmark)

    Irimia, José M; Rovira, Jordi; Nielsen, Jakob N

    2012-01-01

    Glycogen-depleting exercise can lead to supercompensation of muscle glycogen stores, but the biochemical mechanisms of this phenomenon are still not completely understood.......Glycogen-depleting exercise can lead to supercompensation of muscle glycogen stores, but the biochemical mechanisms of this phenomenon are still not completely understood....

  20. Stores

    CERN Multimedia

    2004-01-01

    Following the introduction of Condensators, resistors and potentiometers from the Farnell electronic-catalogue into CERN Stores' catalogue, following products are now available: PRODUCT FAMILY GROUP SCEM Oscillators and quartz crystals 07.94.10 / 07.94.12 Diodes 08.51.14 / 08.51.54 Thyristors 08.51.60 / 08.51.66 Opto-electronics 08.52 Transistors 08.53 Integrated circuits 08.54 / 08.55 These articles can be procured in the same way as any other stores item, by completing a Material Request. N.B. Individual Farnell order codes can be used as keywords to facilitate searches in the CERN Stores Catalogue.

  1. Replenishment at sea

    Directory of Open Access Journals (Sweden)

    Bohdan Pac

    2012-12-01

    Full Text Available Replenishment at sea is a process which plays the key role in the contemporary naval logistics during military and crisis operations. As the last element of the supply chain, it must use specific standards within the areas of procedures, technical equipment, logistic assets and resources, as well as safety, especially in multinational operations. The methods applied enable ships to operate at sea in the long term without logistic support provided by sea ports. The paper explains all the methods of the solids and liquids replenishment, and also gives an idea how to estimate the resupply process, using the measures. The level of standardization of procedures and assets implemented by NATO, the EU and other willing states has been described.

  2. High glycogen levels in the hippocampus of patients with epilepsy

    DEFF Research Database (Denmark)

    Dalsgaard, Mads K; Madsen, Flemming F; Secher, Niels H

    2006-01-01

    During intense cerebral activation approximately half of the glucose plus lactate taken up by the human brain is not oxidized and could replenish glycogen deposits, but the human brain glycogen concentration is unknown. In patients with temporal lobe epilepsy, undergoing curative surgery, brain......, glycogen was similarly higher than in grey and white matter. Consequently, in human grey and white matter and, particularly, in the hippocampus of patients with temporal lope epilepsy, glycogen constitutes a large, active energy reserve, which may be of importance for energy provision during sustained...

  3. Biomarker for Glycogen Storage Diseases

    Science.gov (United States)

    2017-07-03

    Fructose Metabolism, Inborn Errors; Glycogen Storage Disease; Glycogen Storage Disease Type I; Glycogen Storage Disease Type II; Glycogen Storage Disease Type III; Glycogen Storage Disease Type IV; Glycogen Storage Disease Type V; Glycogen Storage Disease Type VI; Glycogen Storage Disease Type VII; Glycogen Storage Disease Type VIII

  4. Brain glycogen in health and disease.

    Science.gov (United States)

    Duran, Jordi; Guinovart, Joan J

    2015-12-01

    Glycogen is present in the brain at much lower concentrations than in muscle or liver. However, by characterizing an animal depleted of brain glycogen, we have shown that the polysaccharide plays a key role in learning capacity and in activity-dependent changes in hippocampal synapse strength. Since glycogen is essentially found in astrocytes, the diverse roles proposed for this polysaccharide in the brain have been attributed exclusively to these cells. However, we have demonstrated that neurons have an active glycogen metabolism that contributes to tolerance to hypoxia. However, these cells can store only minute amounts of glycogen, since the progressive accumulation of this molecule leads to neuronal loss. Loss-of-function mutations in laforin and malin cause Lafora disease. This condition is characterized by the presence of high numbers of insoluble polyglucosan bodies, known as Lafora bodies, in neuronal cells. Our findings reveal that the accumulation of this aberrant glycogen accounts for the neurodegeneration and functional consequences, as well as the impaired autophagy, observed in models of this disease. Similarly glycogen synthase is responsible for the accumulation of corpora amylacea, which are polysaccharide-based aggregates present in the neurons of aged human brains. Our findings change the current view of the role of glycogen in the brain and reveal that endogenous neuronal glycogen metabolism is important under stress conditions and that neuronal glycogen accumulation contributes to neurodegenerative diseases and to aging-related corpora amylacea formation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Approximation algorithms for replenishment problems with fixed turnover times

    NARCIS (Netherlands)

    T. Bosman (Thomas); M. van Ee (Martijn); Y. Jiao (Yang); A. Marchetti Spaccamela (Alberto); R. Ravi; L. Stougie (Leen)

    2018-01-01

    textabstractWe introduce and study a class of optimization problems we coin replenishment problems with fixed turnover times: a very natural model that has received little attention in the literature. Nodes with capacity for storing a certain commodity are located at various places; at each node the

  6. Revisiting Glycogen Content in the Human Brain.

    Science.gov (United States)

    Öz, Gülin; DiNuzzo, Mauro; Kumar, Anjali; Moheet, Amir; Seaquist, Elizabeth R

    2015-12-01

    Glycogen provides an important glucose reservoir in the brain since the concentration of glucosyl units stored in glycogen is several fold higher than free glucose available in brain tissue. We have previously reported 3-4 µmol/g brain glycogen content using in vivo (13)C magnetic resonance spectroscopy (MRS) in conjunction with [1-(13)C]glucose administration in healthy humans, while higher levels were reported in the rodent brain. Due to the slow turnover of bulk brain glycogen in humans, complete turnover of the glycogen pool, estimated to take 3-5 days, was not observed in these prior studies. In an attempt to reach complete turnover and thereby steady state (13)C labeling in glycogen, here we administered [1-(13)C]glucose to healthy volunteers for 80 h. To eliminate any net glycogen synthesis during this period and thereby achieve an accurate estimate of glycogen concentration, volunteers were maintained at euglycemic blood glucose levels during [1-(13)C]glucose administration and (13)C-glycogen levels in the occipital lobe were measured by (13)C MRS approximately every 12 h. Finally, we fitted the data with a biophysical model that was recently developed to take into account the tiered structure of the glycogen molecule and additionally incorporated blood glucose levels and isotopic enrichments as input function in the model. We obtained excellent fits of the model to the (13)C-glycogen data, and glycogen content in the healthy human brain tissue was found to be 7.8 ± 0.3 µmol/g, a value substantially higher than previous estimates of glycogen content in the human brain.

  7. Postexercise muscle glycogen resynthesis in humans.

    Science.gov (United States)

    Burke, Louise M; van Loon, Luc J C; Hawley, John A

    2017-05-01

    Since the pioneering studies conducted in the 1960s in which glycogen status was investigated using the muscle biopsy technique, sports scientists have developed a sophisticated appreciation of the role of glycogen in cellular adaptation and exercise performance, as well as sites of storage of this important metabolic fuel. While sports nutrition guidelines have evolved during the past decade to incorporate sport-specific and periodized manipulation of carbohydrate (CHO) availability, athletes attempt to maximize muscle glycogen synthesis between important workouts or competitive events so that fuel stores closely match the demands of the prescribed exercise. Therefore, it is important to understand the factors that enhance or impair this biphasic process. In the early postexercise period (0-4 h), glycogen depletion provides a strong drive for its own resynthesis, with the provision of CHO (~1 g/kg body mass) optimizing this process. During the later phase of recovery (4-24 h), CHO intake should meet the anticipated fuel needs of the training/competition, with the type, form, and pattern of intake being less important than total intake. Dietary strategies that can enhance glycogen synthesis from suboptimal amounts of CHO or energy intake are of practical interest to many athletes; in this scenario, the coingestion of protein with CHO can assist glycogen storage. Future research should identify other factors that enhance the rate of synthesis of glycogen storage in a limited time frame, improve glycogen storage from a limited CHO intake, or increase muscle glycogen supercompensation. Copyright © 2017 the American Physiological Society.

  8. Genetics Home Reference: glycogen storage disease type 0

    Science.gov (United States)

    ... skeletal muscle, glycogen stored in muscle cells is broken down to supply the cells with energy. The ... that is stored in the liver can be broken down rapidly when glucose is needed to maintain ...

  9. Automation of periodic replenishment process for fashionable product

    OpenAIRE

    Lauwerier, Rémi

    2015-01-01

    The thesis depicted in this report was the subject of my internship at Dior Haute Couture in Paris. I was a member of the supply chain team and I was working on the women shoes product. The aim was to develop the automation of the replenishment of the stores in the world. As a planner for Europe and the United States, I was in strong interaction with the buyers who were following specific stores and who have strong knowledge about the product. The product required a well understanding of the ...

  10. Investigation and management of the hepatic glycogen storage diseases.

    Science.gov (United States)

    Bhattacharya, Kaustuv

    2015-07-01

    The glycogen storage diseases (GSD) comprise a group of disorders that involve the disruption of metabolism of glycogen. Glycogen is stored in various organs including skeletal muscle, the kidneys and liver. The liver stores glycogen to supply the rest of the body with glucose when required. Therefore, disruption of this process can lead to hypoglycaemia. If glycogen is not broken down effectively, this can lead to hepatomegaly. Glycogen synthase deficiency leads to impaired glycogen synthesis and consequently the liver is small. Glycogen brancher deficiency can lead to abnormal glycogen being stored in the liver leading to a quite different disorder of progressive liver dysfunction. Understanding the physiology of GSD I, III, VI and IX guides dietary treatments and the provision of appropriate amounts and types of carbohydrates. There has been recent re-emergence in the literature of the use of ketones in therapy, either in the form of the salt D,L-3-hydroxybutyrate or medium chain triglyceride (MCT). High protein diets have also been advocated. Alternative waxy maize based starches seem to show promising early data of efficacy. There are many complications of each of these disorders and they need to be prospectively surveyed and managed. Liver and kidney transplantation is still indicated in severe refractory disease.

  11. Glycogen and its metabolism: some new developments and old themes

    Science.gov (United States)

    Roach, Peter J.; Depaoli-Roach, Anna A.; Hurley, Thomas D.; Tagliabracci, Vincent S.

    2016-01-01

    Glycogen is a branched polymer of glucose that acts as a store of energy in times of nutritional sufficiency for utilization in times of need. Its metabolism has been the subject of extensive investigation and much is known about its regulation by hormones such as insulin, glucagon and adrenaline (epinephrine). There has been debate over the relative importance of allosteric compared with covalent control of the key biosynthetic enzyme, glycogen synthase, as well as the relative importance of glucose entry into cells compared with glycogen synthase regulation in determining glycogen accumulation. Significant new developments in eukaryotic glycogen metabolism over the last decade or so include: (i) three-dimensional structures of the biosynthetic enzymes glycogenin and glycogen synthase, with associated implications for mechanism and control; (ii) analyses of several genetically engineered mice with altered glycogen metabolism that shed light on the mechanism of control; (iii) greater appreciation of the spatial aspects of glycogen metabolism, including more focus on the lysosomal degradation of glycogen; and (iv) glycogen phosphorylation and advances in the study of Lafora disease, which is emerging as a glycogen storage disease. PMID:22248338

  12. Hyper-hippocampal glycogen induced by glycogen loading with exhaustive exercise.

    Science.gov (United States)

    Soya, Mariko; Matsui, Takashi; Shima, Takeru; Jesmin, Subrina; Omi, Naomi; Soya, Hideaki

    2018-01-19

    Glycogen loading (GL), a well-known type of sports conditioning, in combination with exercise and a high carbohydrate diet (HCD) for 1 week enhances individual endurance capacity through muscle glycogen supercompensation. This exercise-diet combination is necessary for successful GL. Glycogen in the brain contributes to hippocampus-related memory functions and endurance capacity. Although the effect of HCD on the brain remains unknown, brain supercompensation occurs following exhaustive exercise (EE), a component of GL. We thus employed a rat model of GL and examined whether GL increases glycogen levels in the brain as well as in muscle, and found that GL increased glycogen levels in the hippocampus and hypothalamus, as well as in muscle. We further explored the essential components of GL (exercise and/or diet conditions) to establish a minimal model of GL focusing on the brain. Exercise, rather than a HCD, was found to be crucial for GL-induced hyper-glycogen in muscle, the hippocampus and the hypothalamus. Moreover, EE was essential for hyper-glycogen only in the hippocampus even without HCD. Here we propose the EE component of GL without HCD as a condition that enhances brain glycogen stores especially in the hippocampus, implicating a physiological strategy to enhance hippocampal functions.

  13. Glycogen metabolism in Schistosoma mansoni worms after their isolation from the host

    NARCIS (Netherlands)

    Tiolens, A.G.M.; Bergh, S.G. van den

    Adult Schistosoma mansoni worms rapidly degrade their endogenous glycogen stores immediately after isolation from the host. In NCTC 109 or in a diphasic culture medium the glycogen levels slowly recovered again after the initial decrease. The rapid degradation of glycogen could be prevented, even in

  14. 2025 Aerospace Replenishment: The Insidious Force Multiplier

    National Research Council Canada - National Science Library

    Smith, Yoshio

    1996-01-01

    .... Even if this were possible, replenishment should be better exploited to mitigate the effect of supporting all or most operations from the United States a likely prospect in the not too distant future...

  15. Drug induced exocytosis of glycogen in Pompe disease.

    Science.gov (United States)

    Turner, Christopher T; Fuller, Maria; Hopwood, John J; Meikle, Peter J; Brooks, Doug A

    2016-10-28

    Pompe disease is caused by a deficiency in the lysosomal enzyme α-glucosidase, and this leads to glycogen accumulation in the autolysosomes of patient cells. Glycogen storage material is exocytosed at a basal rate in cultured Pompe cells, with one study showing up to 80% is released under specific culture conditions. Critically, exocytosis induction may reduce glycogen storage in Pompe patients, providing the basis for a therapeutic strategy whereby stored glycogen is redirected to an extracellular location and subsequently degraded by circulating amylases. The focus of the current study was to identify compounds capable of inducing rapid glycogen exocytosis in cultured Pompe cells. Here, calcimycin, lysophosphatidylcholine and α-l-iduronidase each significantly increased glycogen exocytosis compared to vehicle-treated controls. The most effective compound, calcimycin, induced exocytosis through a Ca 2+ -dependent mechanism, although was unable to release a pool of vesicular glycogen larger than the calcimycin-induced exocytic pore. There was reduced glycogen release from Pompe compared to unaffected cells, primarily due to increased granule size in Pompe cells. Drug induced exocytosis therefore shows promise as a therapeutic approach for Pompe patients but strategies are required to enhance the release of large molecular weight glycogen granules. Copyright © 2016. Published by Elsevier Inc.

  16. Abnormal Glycogen Storage by Retinal Neurons in Diabetes.

    Science.gov (United States)

    Gardiner, Tom A; Canning, Paul; Tipping, Nuala; Archer, Desmond B; Stitt, Alan W

    2015-12-01

    It is widely held that neurons of the central nervous system do not store glycogen and that accumulation of the polysaccharide may cause neurodegeneration. Since primary neural injury occurs in diabetic retinopathy, we examined neuronal glycogen status in the retina of streptozotocin-induced diabetic and control rats. Glycogen was localized in eyes of streptozotocin-induced diabetic and control rats using light microscopic histochemistry and electron microscopy, and correlated with immunohistochemical staining for glycogen phosphorylase and phosphorylated glycogen synthase (pGS). Electron microscopy of 2-month-old diabetic rats (n = 6) showed massive accumulations of glycogen in the perinuclear cytoplasm of many amacrine neurons. In 4-month-old diabetic rats (n = 11), quantification of glycogen-engorged amacrine cells showed a mean of 26 cells/mm of central retina (SD ± 5), compared to 0.5 (SD ± 0.2) in controls (n = 8). Immunohistochemical staining for glycogen phosphorylase revealed strong expression in amacrine and ganglion cells of control retina, and increased staining in cell processes of the inner plexiform layer in diabetic retina. In control retina, the inactive pGS was consistently sequestered within the cell nuclei of all retinal neurons and the retinal pigment epithelium (RPE), but in diabetics nuclear pGS was reduced or lost in all classes of retinal cell except the ganglion cells and cone photoreceptors. The present study identifies a large population of retinal neurons that normally utilize glycogen metabolism but show pathologic storage of the polysaccharide during uncontrolled diabetes.

  17. Glycogen distribution in adult and geriatric mice brains

    KAUST Repository

    Alrabeh, Rana

    2017-05-01

    Astrocytes, the most abundant glial cell type in the brain, undergo a number of roles in brain physiology; among them, the energetic support of neurons is the best characterized. Contained within astrocytes is the brain’s obligate energy store, glycogen. Through glycogenolysis, glycogen, a storage form of glucose, is converted to pyruvate that is further reduced to lactate and transferred to neurons as an energy source via MCTs. Glycogen is a multi-branched polysaccharide synthesized from the glucose uptaken in astrocytes. It has been shown that glycogen accumulates with age and contributes to the physiological ageing process in the brain. In this study, we compared glycogen distribution between young adults and geriatric mice to understand the energy consumption of synaptic terminals during ageing using computational tools. We segmented and densely reconstructed neuropil and glycogen granules within six (three 4 month old old and three 24 month old) volumes of Layer 1 somatosensory cortex mice brains from FIB-SEM stacks, using a combination of semi-automated and manual tools, ilastik and TrakEM2. Finally, the 3D visualization software, Blender, was used to analyze the dataset using the DBSCAN and KDTree Nearest neighbor algorithms to study the distribution of glycogen granules compared to synapses, using a plugin that was developed for this purpose. The Nearest Neighbors and clustering results of 6 datasets show that glycogen clusters around excitatory synapses more than inhibitory synapses and that, in general, glycogen is found around axonal boutons more than dendritic spines. There was no significant accumulation of glycogen with ageing within our admittedly small dataset. However, there was a homogenization of glycogen distribution with age and that is consistent with published literature. We conclude that glycogen distribution in the brain is not a random process but follows a function distribution.

  18. Neuronal glycogen synthesis contributes to physiological aging.

    Science.gov (United States)

    Sinadinos, Christopher; Valles-Ortega, Jordi; Boulan, Laura; Solsona, Estel; Tevy, Maria F; Marquez, Mercedes; Duran, Jordi; Lopez-Iglesias, Carmen; Calbó, Joaquim; Blasco, Ester; Pumarola, Marti; Milán, Marco; Guinovart, Joan J

    2014-10-01

    Glycogen is a branched polymer of glucose and the carbohydrate energy store for animal cells. In the brain, it is essentially found in glial cells, although it is also present in minute amounts in neurons. In humans, loss-of-function mutations in laforin and malin, proteins involved in suppressing glycogen synthesis, induce the presence of high numbers of insoluble polyglucosan bodies in neuronal cells. Known as Lafora bodies (LBs), these deposits result in the aggressive neurodegeneration seen in Lafora's disease. Polysaccharide-based aggregates, called corpora amylacea (CA), are also present in the neurons of aged human brains. Despite the similarity of CA to LBs, the mechanisms and functional consequences of CA formation are yet unknown. Here, we show that wild-type laboratory mice also accumulate glycogen-based aggregates in the brain as they age. These structures are immunopositive for an array of metabolic and stress-response proteins, some of which were previously shown to aggregate in correlation with age in the human brain and are also present in LBs. Remarkably, these structures and their associated protein aggregates are not present in the aged mouse brain upon genetic ablation of glycogen synthase. Similar genetic intervention in Drosophila prevents the accumulation of glycogen clusters in the neuronal processes of aged flies. Most interestingly, targeted reduction of Drosophila glycogen synthase in neurons improves neurological function with age and extends lifespan. These results demonstrate that neuronal glycogen accumulation contributes to physiological aging and may therefore constitute a key factor regulating age-related neurological decline in humans. © 2014 The Authors. Aging cell published by the Anatomical Society and John Wiley & Sons Ltd.

  19. Muscle and liver glycogen, protein, and triglyceride in the rat

    DEFF Research Database (Denmark)

    Richter, Erik; Sonne, Bente; Joensen Mikines, Kari

    1984-01-01

    in skeletal muscle was accompanied by increased breakdown of triglyceride and/or protein. Thus, the effect of exhausting swimming and of running on concentrations of glycogen, protein, and triglyceride in skeletal muscle and liver were studied in rats with and without deficiencies of the sympatho......-adrenal system. In control rats, both swimming and running decreased the concentration of glycogen in fast-twitch red and slow-twitch red muscle whereas concentrations of protein and triglyceride did not decrease. In the liver, swimming depleted glycogen stores but protein and triglyceride concentrations did...... not decrease. In exercising rats, muscle glycogen breakdown was impaired by adrenodemedullation and restored by infusion of epinephrine. However, impaired glycogen breakdown during exercise was not accompanied by a significant net breakdown of protein or triglyceride. Surgical sympathectomy of the muscles did...

  20. Role of glycogen availability in sarcoplasmic reticulum Ca2+ kinetics in human skeletal muscle

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Nielsen, Joachim; Saltin, Bengt

    2011-01-01

    Glucose is stored as glycogen in skeletal muscle. The importance of glycogen as a fuel during exercise has been recognized since the 1960s; however, little is known about the precise mechanism that relates skeletal muscle glycogen to muscle fatigue. We show that low muscle glycogen is associated...... with an impairment of muscle ability to release Ca(2+), which is an important signal in the muscle activation. Thus, depletion of glycogen during prolonged, exhausting exercise may contribute to muscle fatigue by causing decreased Ca(2+) release inside the muscle. These data provide indications of a signal...

  1. Contributions of Glycogen to Astrocytic Energetics during Brain Activation

    Science.gov (United States)

    Dienel, Gerald A.; Cruz, Nancy F.

    2014-01-01

    Glycogen is the major store of glucose in brain and is mainly in astrocytes. Brain glycogen levels in unstimulated, carefully-handled rats are 10-12 mol/g, and assuming that astrocytes account for half the brain mass, astrocytic glycogen content is twice as high. Glycogen turnover is slow under basal conditions, but it is mobilized during activation. There is no net increase in incorporation of label from glucose during activation, whereas label release from pre-labeled glycogen exceeds net glycogen consumption, which increases during stronger stimuli. Because glycogen level is restored by non-oxidative metabolism, astrocytes can influence the global ratio of oxygen to glucose utilization. Compensatory increases in utilization of blood glucose during inhibition of glycogen phosphorylase are large and approximate glycogenolysis rates during sensory stimulation. In contrast, glycogenolysis rates during hypoglycemia are low due to continued glucose delivery and oxidation of endogenous substrates; rates that preserve neuronal function in the absence of glucose are also low, probably due to metabolite oxidation. Modeling studies predict that glycogenolysis maintains a high level of glucose-6-phosphate in astrocytes to maintain feedback inhibition of hexokinase, thereby diverting glucose for use by neurons. The fate of glycogen carbon in vivo is not known, but lactate efflux from brain best accounts for the major metabolic characteristics during activation of living brain. Substantial shuttling coupled with oxidation of glycogen-derived lactate is inconsistent with available evidence. Glycogen has important roles in astrocytic energetics, including glucose sparing, control of extracellular K+ level, oxidative stress management, and memory consolidation; it is a multi-functional compound. PMID:24515302

  2. Contributions of glycogen to astrocytic energetics during brain activation.

    Science.gov (United States)

    Dienel, Gerald A; Cruz, Nancy F

    2015-02-01

    Glycogen is the major store of glucose in brain and is mainly in astrocytes. Brain glycogen levels in unstimulated, carefully-handled rats are 10-12 μmol/g, and assuming that astrocytes account for half the brain mass, astrocytic glycogen content is twice as high. Glycogen turnover is slow under basal conditions, but it is mobilized during activation. There is no net increase in incorporation of label from glucose during activation, whereas label release from pre-labeled glycogen exceeds net glycogen consumption, which increases during stronger stimuli. Because glycogen level is restored by non-oxidative metabolism, astrocytes can influence the global ratio of oxygen to glucose utilization. Compensatory increases in utilization of blood glucose during inhibition of glycogen phosphorylase are large and approximate glycogenolysis rates during sensory stimulation. In contrast, glycogenolysis rates during hypoglycemia are low due to continued glucose delivery and oxidation of endogenous substrates; rates that preserve neuronal function in the absence of glucose are also low, probably due to metabolite oxidation. Modeling studies predict that glycogenolysis maintains a high level of glucose-6-phosphate in astrocytes to maintain feedback inhibition of hexokinase, thereby diverting glucose for use by neurons. The fate of glycogen carbon in vivo is not known, but lactate efflux from brain best accounts for the major metabolic characteristics during activation of living brain. Substantial shuttling coupled with oxidation of glycogen-derived lactate is inconsistent with available evidence. Glycogen has important roles in astrocytic energetics, including glucose sparing, control of extracellular K(+) level, oxidative stress management, and memory consolidation; it is a multi-functional compound.

  3. Glycogen synthesis from lactate in a chronically active muscle

    International Nuclear Information System (INIS)

    Talmadge, R.J.; Scheide, J.I.; Silverman, H.

    1989-01-01

    In response to neural overactivity (pseudomyotonia), gastrocnemius muscle fibers from C57Bl/6Jdy2J/dy2J mice have different metabolic profiles compared with normal mice. A population of fibers in the fast-twitch superficial region of the dy2J gastrocnemius stores unusually high amounts of glycogen, leading to an increased glycogen storage in the whole muscle. The dy2J muscle also contains twice as much lactate as normal muscle. A [ 14 C]lactate intraperitoneal injection leads to preferential 14 C incorporation into glycogen in the dy2J muscle compared with normal muscle. To determine whether skeletal muscles were incorporating lactate into glycogen without body organ (liver, kidney) input, gastrocnemius muscles were bathed in 10 mM [ 14 C]lactate with intact neural and arterial supply but with impeded venous return. The contralateral gastrocnemius serves as a control for body organ input. By using this in situ procedure, we demonstrate that under conditions of high lactate both normal and dy2J muscle can directly synthesize glycogen from lactate. In this case, normal whole muscle incorporates [14C] lactate into glycogen at a higher rate than dy2J whole muscle. Autoradiography, however, suggests that the high-glycogen-containing muscle fibers in the dy2J muscle incorporate lactate into glycogen at nearly four times the rate of normal or surrounding muscle fibers

  4. Molecular Basis of Impaired Glycogen Metabolism during Ischemic Stroke and Hypoxia

    Science.gov (United States)

    Hossain, Mohammed Iqbal; Roulston, Carli Lorraine; Stapleton, David Ian

    2014-01-01

    Background Ischemic stroke is the combinatorial effect of many pathological processes including the loss of energy supplies, excessive intracellular calcium accumulation, oxidative stress, and inflammatory responses. The brain's ability to maintain energy demand through this process involves metabolism of glycogen, which is critical for release of stored glucose. However, regulation of glycogen metabolism in ischemic stroke remains unknown. In the present study, we investigate the role and regulation of glycogen metabolizing enzymes and their effects on the fate of glycogen during ischemic stroke. Results Ischemic stroke was induced in rats by peri-vascular application of the vasoconstrictor endothelin-1 and forebrains were collected at 1, 3, 6 and 24 hours post-stroke. Glycogen levels and the expression and activity of enzymes involved in glycogen metabolism were analyzed. We found elevated glycogen levels in the ipsilateral hemispheres compared with contralateral hemispheres at 6 and 24 hours (25% and 39% increase respectively; PGlycogen synthase activity and glycogen branching enzyme expression were found to be similar between the ipsilateral, contralateral, and sham control hemispheres. In contrast, the rate-limiting enzyme for glycogen breakdown, glycogen phosphorylase, had 58% lower activity (Pglycogen debranching enzyme expression 24 hours post-stroke was 77% (Pglycogen phosphorylase activity and increased glycogen accumulation but did not alter glycogen synthase activity. Furthermore, elevated glycogen levels provided metabolic support to astrocytes during hypoxia. Conclusion Our study has identified that glycogen breakdown is impaired during ischemic stroke, the molecular basis of which includes reduced glycogen debranching enzyme expression level together with reduced glycogen phosphorylase and PKA activity. PMID:24858129

  5. Optimal dynamic pricing and replenishment policy for perishable items with inventory-level-dependent demand

    Science.gov (United States)

    Lu, Lihao; Zhang, Jianxiong; Tang, Wansheng

    2016-04-01

    An inventory system for perishable items with limited replenishment capacity is introduced in this paper. The demand rate depends on the stock quantity displayed in the store as well as the sales price. With the goal to realise profit maximisation, an optimisation problem is addressed to seek for the optimal joint dynamic pricing and replenishment policy which is obtained by solving the optimisation problem with Pontryagin's maximum principle. A joint mixed policy, in which the sales price is a static decision variable and the replenishment rate remains to be a dynamic decision variable, is presented to compare with the joint dynamic policy. Numerical results demonstrate the advantages of the joint dynamic one, and further show the effects of different system parameters on the optimal joint dynamic policy and the maximal total profit.

  6. Disposable penis and its replenishment in a simultaneous hermaphrodite

    Science.gov (United States)

    Sekizawa, Ayami; Seki, Satoko; Tokuzato, Masakazu; Shiga, Sakiko; Nakashima, Yasuhiro

    2013-01-01

    Although it is often thought that sexual selection is weaker in simultaneous hermaphrodites than in gonochorists, some simultaneous hermaphrodites exhibit bizarre mating behaviour. In the simultaneously hermaphroditic nudibranch Chromodoris reticulata, we found a peculiar mating behaviour, wherein the nudibranch autotomized its penis after each copulation and was able to copulate again within 24 h. To have sufficient length to be replenished for three copulations, the penis is compressed and spiralled internally. No other animal is known to repeatedly copulate using such ‘disposable penes’. Entangled sperm masses were observed on the outer surface of the autotomized penis, which is equipped with many backward-pointed spines. There is a possibility that the nudibranch removes sperm already stored in a mating partner's sperm storage organ(s). PMID:23407499

  7. Incorporation of phosphate into glycogen by glycogen synthase.

    Science.gov (United States)

    Contreras, Christopher J; Segvich, Dyann M; Mahalingan, Krishna; Chikwana, Vimbai M; Kirley, Terence L; Hurley, Thomas D; DePaoli-Roach, Anna A; Roach, Peter J

    2016-05-01

    The storage polymer glycogen normally contains small amounts of covalently attached phosphate as phosphomonoesters at C2, C3 and C6 atoms of glucose residues. In the absence of the laforin phosphatase, as in the rare childhood epilepsy Lafora disease, the phosphorylation level is elevated and is associated with abnormal glycogen structure that contributes to the pathology. Laforin therefore likely functions in vivo as a glycogen phosphatase. The mechanism of glycogen phosphorylation is less well-understood. We have reported that glycogen synthase incorporates phosphate into glycogen via a rare side reaction in which glucose-phosphate rather than glucose is transferred to a growing polyglucose chain (Tagliabracci et al. (2011) Cell Metab13, 274-282). We proposed a mechanism to account for phosphorylation at C2 and possibly at C3. Our results have since been challenged (Nitschke et al. (2013) Cell Metab17, 756-767). Here we extend the evidence supporting our conclusion, validating the assay used for the detection of glycogen phosphorylation, measurement of the transfer of (32)P from [β-(32)P]UDP-glucose to glycogen by glycogen synthase. The (32)P associated with the glycogen fraction was stable to ethanol precipitation, SDS-PAGE and gel filtration on Sephadex G50. The (32)P-signal was not affected by inclusion of excess unlabeled UDP before analysis or by treatment with a UDPase, arguing against the signal being due to contaminating [β-(32)P]UDP generated in the reaction. Furthermore, [(32)P]UDP did not bind non-covalently to glycogen. The (32)P associated with glycogen was released by laforin treatment, suggesting that it was present as a phosphomonoester. The conclusion is that glycogen synthase can mediate the introduction of phosphate into glycogen, thereby providing a possible mechanism for C2, and perhaps C3, phosphorylation. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. A Joint Replenishment Inventory Model with Lost Sales

    Science.gov (United States)

    Devy, N. L.; Ai, T. J.; Astanti, R. D.

    2018-04-01

    This paper deals with two items joint replenishment inventory problem, in which the demand of each items are constant and deterministic. Inventory replenishment of items is conducted periodically every T time intervals. Among of these replenishments, joint replenishment of both items is possible. It is defined that item i is replenished every ZiT time intervals. Replenishment of items are instantaneous. All of shortages are considered as lost sales. The maximum allowance for lost sales of item i is Si. Mathematical model is formulated in order to determining the basic time cycle T, replenishment multiplier Zi , and maximum lost sales Si in order to minimize the total cost per unit time. A solution methodology is proposed for solve the model and a numerical example is provided for demonstrating the effectiveness of the proposed methodology.

  9. Glycogen phosphorylation and Lafora disease.

    Science.gov (United States)

    Roach, Peter J

    2015-12-01

    Covalent phosphorylation of glycogen, first described 35 years ago, was put on firm ground through the work of the Whelan laboratory in the 1990s. But glycogen phosphorylation lay fallow until interest was rekindled in the mid 2000s by the finding that it could be removed by a glycogen-binding phosphatase, laforin, and that mutations in laforin cause a fatal teenage-onset epilepsy, called Lafora disease. Glycogen phosphorylation is due to phosphomonoesters at C2, C3 and C6 of glucose residues. Phosphate is rare, ranging from 1:500 to 1:5000 phosphates/glucose depending on the glycogen source. The mechanisms of glycogen phosphorylation remain under investigation but one hypothesis to explain C2 and perhaps C3 phosphate is that it results from a rare side reaction of the normal synthetic enzyme glycogen synthase. Lafora disease is likely caused by over-accumulation of abnormal glycogen in insoluble deposits termed Lafora bodies in neurons. The abnormality in the glycogen correlates with elevated phosphorylation (at C2, C3 and C6), reduced branching, insolubility and an enhanced tendency to aggregate and become insoluble. Hyperphosphorylation of glycogen is emerging as an important feature of this deadly childhood disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Regulation of glucose and glycogen metabolism during and after exercise

    DEFF Research Database (Denmark)

    Jensen, Thomas Elbenhardt; Richter, Erik

    2012-01-01

    Utilization of carbohydrate in the form of intramuscular glycogen stores and glucose delivered from plasma becomes an increasingly important energy substrate to the working muscle with increasing exercise intensity. This review gives an update on the molecular signals by which glucose transport...

  11. Coordinating supplier-retailer using multiple common replenishment epochs with retailers’ choices

    Directory of Open Access Journals (Sweden)

    Juhwen Hwang

    2013-06-01

    Full Text Available Purpose: Provide a coordination strategy using multiple common replenishment epochs (MCRE for a single-supplier multi-retailer supply chain. Design/methodology/approach: The demand of a product occurs only with a group of heterogeneous and independent retailers with constant rates, whereas all their order requests are fulfilled by the supplier. The supplier decides a set of MCREs with general price and extra bonus to entice the retailers to join any one of the MCREs, or to let them remain with their original order time epochs. A retailer is willing to participate in a CRE as long as the retailer’s cost increase is within its tolerance. This paper provide a mixed integer programming to determine the MCRE strategies in order to minimize the total costs of the supplier. Findings: The results illustrate that MCRE model provided in the paper can generate a better replenishment coordination scheme than single CRE models. Practical implications: Replenishment coordination is one of the most important mechanisms to improve the efficiency in supply chains, e.g., chain convenience stores in the modern retail industry. Originality/value: This is a follow-up research on Joint Economic Lot Size (JELS models with a focus on multiple retailers with their replenishment coordination.

  12. Replenishing Humic Acids in Agricultural Soils

    Directory of Open Access Journals (Sweden)

    Michael Susic

    2016-09-01

    Full Text Available For many decades, it was commonly believed that humic acids were formed in soils by the microbial conversion of plant lignins. However, an experiment to test whether these humic acids were formed prior to plant matter reaching the soil was never reported until the late 1980s (and then only as a side issue, even though humic acids were first isolated and reported in 1786. This was a serious omission, and led to a poor understanding of how the humic acid content of soils could be maintained or increased for optimum fertility. In this study, commercial sugar cane mulch and kelp extracts were extracted with alkali and analyzed for humic acid content. Humic acids in the extracts were positively identified by fluorescence spectrophotometry, and this demonstrated that humic acids are formed in senescent plant and algal matter before they reach the soil, where they are then strongly bound to the soil and are also resistant to microbial metabolism. Humic acids are removed from soils by wind and water erosion, and by water leaching, which means that they must be regularly replenished. This study shows that soils can be replenished or fortified with humic acids simply by recycling plant and algal matter, or by adding outside sources of decomposed plant or algal matter such as composts, mulch, peat, and lignite coals.

  13. Glycogen serves as an energy source that maintains astrocyte cell proliferation in the neonatal telencephalon.

    Science.gov (United States)

    Gotoh, Hitoshi; Nomura, Tadashi; Ono, Katsuhiko

    2017-06-01

    Large amounts of energy are required when cells undergo cell proliferation and differentiation for mammalian neuronal development. Early neonatal mice face transient starvation and use stored energy for survival or to support development. Glycogen is a branched polysaccharide that is formed by glucose, and serves as an astrocytic energy store for rapid energy requirements. Although it is present in radial glial cells and astrocytes, the role of glycogen during development remains unclear. In the present study, we demonstrated that glycogen accumulated in glutamate aspartate transporter (GLAST)+ astrocytes in the subventricular zone and rostral migratory stream. Glycogen levels markedly decreased after birth due to the increase of glycogen phosphorylase, an essential enzyme for glycogen metabolism. In primary cultures and in vivo, the inhibition of glycogen phosphorylase decreased the proliferation of astrocytic cells. The number of cells in the G1 phase increased in combination with the up-regulation of cyclin-dependent kinase inhibitors or down-regulation of the phosphorylation of retinoblastoma protein (pRB), a determinant for cell cycle progression. These results suggest that glycogen accumulates in astrocytes located in specific areas during the prenatal stage and is used as an energy source to maintain normal development in the early postnatal stage.

  14. Glycogen Storage Disease Type IV

    DEFF Research Database (Denmark)

    Bendroth-Asmussen, Lisa; Aksglaede, Lise; Gernow, Anne B

    2016-01-01

    molecular genetic analyses confirmed glycogen storage disease Type IV with the finding of compound heterozygosity for 2 mutations (c.691+2T>C and c.1570C>T, p.R524X) in the GBE1 gene. We conclude that glycogen storage disease Type IV can cause early miscarriage and that diagnosis can initially be made...

  15. Insights into Brain Glycogen Metabolism

    Science.gov (United States)

    Mathieu, Cécile; de la Sierra-Gallay, Ines Li; Duval, Romain; Xu, Ximing; Cocaign, Angélique; Léger, Thibaut; Woffendin, Gary; Camadro, Jean-Michel; Etchebest, Catherine; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2016-01-01

    Brain glycogen metabolism plays a critical role in major brain functions such as learning or memory consolidation. However, alteration of glycogen metabolism and glycogen accumulation in the brain contributes to neurodegeneration as observed in Lafora disease. Glycogen phosphorylase (GP), a key enzyme in glycogen metabolism, catalyzes the rate-limiting step of glycogen mobilization. Moreover, the allosteric regulation of the three GP isozymes (muscle, liver, and brain) by metabolites and phosphorylation, in response to hormonal signaling, fine-tunes glycogenolysis to fulfill energetic and metabolic requirements. Whereas the structures of muscle and liver GPs have been known for decades, the structure of brain GP (bGP) has remained elusive despite its critical role in brain glycogen metabolism. Here, we report the crystal structure of human bGP in complex with PEG 400 (2.5 Å) and in complex with its allosteric activator AMP (3.4 Å). These structures demonstrate that bGP has a closer structural relationship with muscle GP, which is also activated by AMP, contrary to liver GP, which is not. Importantly, despite the structural similarities between human bGP and the two other mammalian isozymes, the bGP structures reveal molecular features unique to the brain isozyme that provide a deeper understanding of the differences in the activation properties of these allosteric enzymes by the allosteric effector AMP. Overall, our study further supports that the distinct structural and regulatory properties of GP isozymes contribute to the different functions of muscle, liver, and brain glycogen. PMID:27402852

  16. Protein targeting to glycogen is a master regulator of glycogen synthesis in astrocytes

    OpenAIRE

    E. Ruchti; P.J. Roach; A.A. DePaoli-Roach; P.J. Magistretti; I. Allaman

    2016-01-01

    The storage and use of glycogen, the main energy reserve in the brain, is a metabolic feature of astrocytes. Glycogen synthesis is regulated by Protein Targeting to Glycogen (PTG), a member of specific glycogen-binding subunits of protein phosphatase-1 (PPP1). It positively regulates glycogen synthesis through de-phosphorylation of both glycogen synthase (activation) and glycogen phosphorylase (inactivation). In cultured astrocytes, PTG mRNA levels were previously shown to be enhanced by the ...

  17. Role of glycogen-lowering exercise in the change of fat oxidation in response to a high-fat diet.

    NARCIS (Netherlands)

    Schrauwen, P.; van Marken Lichtenbelt, W.D.; Saris, W.H.M.; Westerterp, K.R.

    1997-01-01

    Department of Human Biology, Maastricht University, The Netherlands. One of the candidate factors for determining the increase of fat oxidation after a switch from a reduced-fat diet to a high-fat diet is the size of the glycogen storage. Therefore, we studied the effect of low glycogen stores on

  18. Subcellular distribution of glycogen and decreased tetanic Ca2+ in fatigued single intact mouse muscle fibres

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Cheng, Arthur J; Ørtenblad, Niels

    2014-01-01

    In skeletal muscle fibres, glycogen has been shown to be stored at different subcellular locations: (i) between the myofibrils (intermyofibrillar); (ii) within the myofibrils (intramyofibrillar); and (iii) subsarcolemmal. Of these, intramyofibrillar glycogen has been implied as a critical regulator...... of sarcoplasmic reticulum Ca(2+) release. The aim of the present study was to test directly how the decrease in cytoplasmic free Ca(2+) ([Ca(2+)]i) during repeated tetanic contractions relates to the subcellular glycogen distribution. Single fibres of mouse flexor digitorum brevis muscles were fatigued with 70 Hz...... in tetanic [Ca(2+)]i, and hence force, is accompanied by major reductions in inter- and intramyofibrillar glycogen. The stronger correlation between decreased tetanic [Ca(2+)]i and reduced intramyofibrillar glycogen implies that sarcoplasmic reticulum Ca(2+) release critically depends on energy supply from...

  19. Is Glycogenin Essential for Glycogen Synthesis?

    Science.gov (United States)

    Oldfors, Anders

    2017-07-05

    Glycogen synthesis requires a priming oligosaccharide, formed by autoglucosylation of glycogenin, a core protein in glycogen particles. In this edition of Cell Metabolism, Testoni et al. (2017) challenge this generally accepted concept by demonstrating that glycogenin inactivation in mice results in an increased amount of glycogen and not glycogen depletion. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Local depletion of glycogen with supramaximal exercise in human skeletal muscle fibres.

    Science.gov (United States)

    Gejl, Kasper D; Ørtenblad, Niels; Andersson, Erik; Plomgaard, Peter; Holmberg, Hans-Christer; Nielsen, Joachim

    2017-05-01

    Glycogen is stored in local spatially distinct compartments within skeletal muscle fibres and is the main energy source during supramaximal exercise. Using quantitative electron microscopy, we show that supramaximal exercise induces a differential depletion of glycogen from these compartments and also demonstrate how this varies with fibre types. Repeated exercise alters this compartmentalized glycogen depletion. The results obtained in the present study help us understand the muscle metabolic dynamics of whole body repeated supramaximal exercise, and suggest that the muscle has a compartmentalized local adaptation to repeated exercise, which affects glycogen depletion. Skeletal muscle glycogen is heterogeneously distributed in three separated compartments (intramyofibrillar, intermyofibrillar and subsarcolemmal). Although only constituting 3-13% of the total glycogen volume, the availability of intramyofibrillar glycogen is of particular importance to muscle function. The present study aimed to investigate the depletion of these three subcellular glycogen compartments during repeated supramaximal exercise in elite athletes. Ten elite cross-country skiers (aged 25 ± 4 years, V̇O2 max : 65 ± 4 ml kg -1  min -1 ; mean ± SD) performed four ∼4 min supramaximal sprint time trials (STT 1-4) with 45 min of recovery. The subcellular glycogen volumes in musculus triceps brachii were quantified from electron microscopy images before and after both STT 1 and 4. During STT 1, the depletion of intramyofibrillar glycogen was higher in type 1 fibres [-52%; (-89:-15%)] than type 2 fibres [-15% (-52:22%)] (P = 0.02), whereas the depletion of intermyofibrillar glycogen [main effect: -19% (-33:0%), P = 0.006] and subsarcolemmal glycogen [main effect: -35% (-66:0%), P = 0.03] was similar between fibre types. By contrast, only intermyofibrillar glycogen volume was significantly reduced during STT 4, in both fibre types [main effect: -31% (-50:-11%), P = 0

  1. Non-invasive measurement of brain glycogen by NMR spectroscopy and its application to the study of brain metabolism

    Science.gov (United States)

    Tesfaye, Nolawit; Seaquist, Elizabeth R.; Öz, Gülin

    2011-01-01

    Glycogen is the reservoir for glucose in the brain. Beyond the general agreement that glycogen serves as an energy source in the central nervous system, its exact role in brain energy metabolism has yet to be elucidated. Experiments performed in cell and tissue culture and animals have shown that glycogen content is affected by several factors including glucose, insulin, neurotransmitters, and neuronal activation. The study of in vivo glycogen metabolism has been hindered by the inability to measure glycogen non-invasively, but in the past several years, the development of a non-invasive localized 13C nuclear magnetic resonance (NMR) spectroscopy method has enabled the study of glycogen metabolism in the conscious human. With this technique, 13C-glucose is administered intravenously and its incorporation into and wash-out from brain glycogen is tracked. One application of this method has been to the study of brain glycogen metabolism in humans during hypoglycemia: data have shown that mobilization of brain glycogen is augmented during hypoglycemia and, after a single episode of hypoglycemia, glycogen synthesis rate is increased, suggesting that glycogen stores rebound to levels greater than baseline. Such studies suggest glycogen may serve as a potential energy reservoir in hypoglycemia and may participate in the brain's adaptation to recurrent hypoglycemia and eventual development of hypoglycemia unawareness. Beyond this focused area of study, 13C NMR spectroscopy has a broad potential for application in the study of brain glycogen metabolism and carries the promise of a better understanding of the role of brain glycogen in diabetes and other conditions. PMID:21732401

  2. Cell-Intrinsic Glycogen Metabolism Supports Early Glycolytic Reprogramming Required for Dendritic Cell Immune Responses.

    Science.gov (United States)

    Thwe, Phyu M; Pelgrom, Leonard; Cooper, Rachel; Beauchamp, Saritha; Reisz, Julie A; D'Alessandro, Angelo; Everts, Bart; Amiel, Eyal

    2017-09-05

    Dendritic cell (DC) activation by Toll-like receptor (TLR) agonists causes rapid glycolytic reprogramming that is required to meet the metabolic demands of their immune activation. Recent efforts in the field have identified an important role for extracellular glucose sourcing to support DC activation. However, the contributions of intracellular glucose stores to these processes have not been well characterized. We demonstrate that DCs possess intracellular glycogen stores and that cell-intrinsic glycogen metabolism supports the early effector functions of TLR-activated DCs. Inhibition of glycogenolysis significantly attenuates TLR-mediated DC maturation and impairs their ability to initiate lymphocyte activation. We further report that DCs exhibit functional compartmentalization of glucose- and glycogen-derived carbons, where these substrates preferentially contribute to distinct metabolic pathways. This work provides novel insights into nutrient homeostasis in DCs, demonstrating that differential utilization of glycogen and glucose metabolism regulates their optimal immune function. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Fat body glycogen serves as a metabolic safeguard for the maintenance of sugar levels in Drosophila.

    Science.gov (United States)

    Yamada, Takayuki; Habara, Okiko; Kubo, Hitomi; Nishimura, Takashi

    2018-03-14

    Adapting to changes in food availability is a central challenge for survival. Glucose is an important resource for energy production, and therefore many organisms synthesize and retain sugar storage molecules. In insects, glucose is stored in two different forms: the disaccharide trehalose and the branched polymer glycogen. Glycogen is synthesized and stored in several tissues, including in muscle and the fat body. Despite the major role of the fat body as a center for energy metabolism, the importance of its glycogen content remains unclear. Here, we show that glycogen metabolism is regulated in a tissue-specific manner under starvation conditions in the fruit fly Drosophila The mobilization of fat body glycogen in larvae is independent of Adipokinetic hormone (Akh, the glucagon homolog) but is regulated by sugar availability in a tissue-autonomous manner. Fat body glycogen plays a crucial role in the maintenance of circulating sugars, including trehalose, under fasting conditions. These results demonstrate the importance of fat body glycogen as a metabolic safeguard in Drosophila . © 2018. Published by The Company of Biologists Ltd.

  4. Type I Glycogen Storage Disease

    Science.gov (United States)

    ... Legacy Society Make Gifts of Stock Donate Your Car Personal Fundraising Partnership & Support Share Your Story Spread the Word Give While You Shop Contact Us Donate Now Glycogen Storage Disease Type ...

  5. Type I Glycogen Storage Disease

    Science.gov (United States)

    ... the most common form of glycogen storage disease, accounting for 25% of all cases. It is an ... Links Videos Webinars About ALF OVERVIEW Programs About Liver Disease Ask the Experts People ALF ...

  6. Protein targeting to glycogen is a master regulator of glycogen synthesis in astrocytes

    KAUST Repository

    Ruchti, E.; Roach, P.J.; DePaoli-Roach, A.A.; Magistretti, Pierre J.; Allaman, I.

    2016-01-01

    to induce glycogen synthesis and accumulation. In contrast, siRNA-mediated downregulation of PTG resulted in a 2-fold decrease in glycogen levels. Interestingly, PTG downregulation strongly impaired long-term astrocytic glycogen synthesis induced by insulin

  7. Sugar versus fat: elimination of glycogen storage improves lipid accumulation in Yarrowia lipolytica.

    Science.gov (United States)

    Bhutada, Govindprasad; Kavšcek, Martin; Ledesma-Amaro, Rodrigo; Thomas, Stéphane; Rechberger, Gerald N; Nicaud, Jean-Marc; Natter, Klaus

    2017-05-01

    Triacylglycerol (TAG) and glycogen are the two major metabolites for carbon storage in most eukaryotic organisms. We investigated the glycogen metabolism of the oleaginous Yarrowia lipolytica and found that this yeast accumulates up to 16% glycogen in its biomass. Assuming that elimination of glycogen synthesis would result in an improvement of lipid accumulation, we characterized and deleted the single gene coding for glycogen synthase, YlGSY1. The mutant was grown under lipogenic conditions with glucose and glycerol as substrates and we obtained up to 60% improvement in TAG accumulation compared to the wild-type strain. Additionally, YlGSY1 was deleted in a background that was already engineered for high lipid accumulation. In this obese background, TAG accumulation was also further increased. The highest lipid content of 52% was found after 3 days of cultivation in nitrogen-limited glycerol medium. Furthermore, we constructed mutants of Y. lipolytica and Saccharomyces cerevisiae that are deleted for both glycogen and TAG synthesis, demonstrating that the ability to store carbon is not essential. Overall, this work showed that glycogen synthesis is a competing pathway for TAG accumulation in oleaginous yeasts and that deletion of the glycogen synthase has beneficial effects on neutral lipid storage. © FEMS 2017.

  8. A Ketone Ester Drink Increases Postexercise Muscle Glycogen Synthesis in Humans.

    Science.gov (United States)

    Holdsworth, David A; Cox, Peter J; Kirk, Tom; Stradling, Huw; Impey, Samuel G; Clarke, Kieran

    2017-09-01

    Physical endurance can be limited by muscle glycogen stores, in that glycogen depletion markedly reduces external work. During carbohydrate restriction, the liver synthesizes the ketone bodies, D-β-hydroxybutyrate, and acetoacetate from fatty acids. In animals and in the presence of glucose, D-β-hydroxybutyrate promotes insulin secretion and increases glycogen synthesis. Here we determined whether a dietary ketone ester, combined with plentiful glucose, can increase postexercise glycogen synthesis in human skeletal muscle. After an interval-based glycogen depletion exercise protocol, 12 well-trained male athletes completed a randomized, three-arm, blinded crossover recovery study that consisted of consumption of either a taste-matched, zero-calorie control or a ketone monoester drink, followed by a 10-mM glucose clamp or saline infusion for 2 h. The three postexercise conditions were control drink then saline infusion, control drink then hyperglycemic clamp, or ketone ester drink then hyperglycemic clamp. Skeletal muscle glycogen content was determined in muscle biopsies of vastus lateralis taken before and after the 2-h clamps. The ketone ester drink increased blood D-β-hydroxybutyrate concentrations to a maximum of 5.3 versus 0.7 mM for the control drink (P glycogen was 50% higher (246 vs 164 mmol glycosyl units per kilogram dry weight, P glycogen synthesis.

  9. Replenishment policy for an inventory model under inflation

    Science.gov (United States)

    Singh, Vikramjeet; Saxena, Seema; Singh, Pushpinder; Mishra, Nitin Kumar

    2017-07-01

    The purpose of replenishment is to keep the flow of inventory in the system. To determine an optimal replenishment policy is a great challenge in developing an inventory model. Inflation is defined as the rate at which the prices of goods and services are rising over a time period. The cost parameters are affected by the rate of inflation. High rate of inflation affects the organizations financial conditions. Based on the above backdrop the present paper proposes the retailers replenishment policy for deteriorating items with different cycle lengths under inflation. The shortages are partially backlogged. At last numerical examples validate the results.

  10. 13C MRS Studies of the Control of Hepatic Glycogen Metabolism at High Magnetic Fields

    Directory of Open Access Journals (Sweden)

    Corin O. Miller

    2017-06-01

    Full Text Available Introduction: Glycogen is the primary intracellular storage form of carbohydrates. In contrast to most tissues where stored glycogen can only supply the local tissue with energy, hepatic glycogen is mobilized and released into the blood to maintain appropriate circulating glucose levels, and is delivered to other tissues as glucose in response to energetic demands. Insulin and glucagon, two current targets of high interest in the pharmaceutical industry, are well-known glucose-regulating hormones whose primary effect in liver is to modulate glycogen synthesis and breakdown. The purpose of these studies was to develop methods to measure glycogen metabolism in real time non-invasively both in isolated mouse livers, and in non-human primates (NHPs using 13C MRS.Methods: Livers were harvested from C57/Bl6 mice and perfused with [1-13C] Glucose. To demonstrate the ability to measure acute changes in glycogen metabolism ex-vivo, fructose, glucagon, and insulin were administered to the liver ex-vivo. The C1 resonance of glycogen was measured in real time with 13C MRS using an 11.7T (500 MHz NMR spectrometer. To demonstrate the translatability of this approach, NHPs (male rhesus monkeys were studied in a 7 T Philips MRI using a partial volume 1H/13C imaging coil. NPHs were subjected to a variable IV infusion of [1-13C] glucose (to maintain blood glucose at 3-4x basal, along with a constant 1 mg/kg/min infusion of fructose. The C1 resonance of glycogen was again measured in real time with 13C MRS. To demonstrate the ability to measure changes in glycogen metabolism in vivo, animals received a glucagon infusion (1 μg/kg bolus followed by 40 ng/kg/min constant infusion half way through the study on the second study session.Results: In both perfused mouse livers and in NHPs, hepatic 13C-glycogen synthesis (i.e., monotonic increases in the 13C-glycogen NMR signal was readily detected. In both paradigms, addition of glucagon resulted in cessation of glycogen

  11. Power Replenishment Patch for Spacecraft Health Monitoring Sensors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Metis Design Corporation (MDC) proposes the development of a strain-based power replenishment technology to harvest energy for recharging remote sensors. MDC has...

  12. Mechanistic Modeling of Water Replenishment Rate of Zeer Refrigerator

    Directory of Open Access Journals (Sweden)

    B. N. Nwankwojike

    2017-06-01

    Full Text Available A model for predicting the water replenishment rate of zeer pot refrigerator was developed in this study using mechanistic modeling approach and evaluated at Obowo, Imo State, Nigeria using six fruits, tomatoes, guava, okra, banana, orange and avocado pear. The developed model confirmed zeer pot water replenishment rate as a function of ambient temperature, relative humidity, wind speed, thermal conductivity of the pot materials and sand, density of air and water vapor, permeability coefficient of clay and heat transfer coefficient of water into air, circumferential length, height of pot, geometrical profile of the pot, heat load of the food preserved, heat flow into the device and gradient at which the pot is placed above ground level. Compared to the conventional approach of water replenishment, performance analysis results revealed 44% to 58% water economy when the zeer pot’s water was replenished based on the model’s prediction; while there was no significant difference in the shelf-life of the fruits preserved with both replenishment methods. Application of the developed water replenishment model facilitates optimal water usage in this system, thereby reducing operational cost of zeer pot refrigerator.

  13. Astrocytic glycogen-derived lactate fuels the brain during exhaustive exercise to maintain endurance capacity.

    Science.gov (United States)

    Matsui, Takashi; Omuro, Hideki; Liu, Yu-Fan; Soya, Mariko; Shima, Takeru; McEwen, Bruce S; Soya, Hideaki

    2017-06-13

    Brain glycogen stored in astrocytes provides lactate as an energy source to neurons through monocarboxylate transporters (MCTs) to maintain neuronal functions such as hippocampus-regulated memory formation. Although prolonged exhaustive exercise decreases brain glycogen, the role of this decrease and lactate transport in the exercising brain remains less clear. Because muscle glycogen fuels exercising muscles, we hypothesized that astrocytic glycogen plays an energetic role in the prolonged-exercising brain to maintain endurance capacity through lactate transport. To test this hypothesis, we used a rat model of exhaustive exercise and capillary electrophoresis-mass spectrometry-based metabolomics to observe comprehensive energetics of the brain (cortex and hippocampus) and muscle (plantaris). At exhaustion, muscle glycogen was depleted but brain glycogen was only decreased. The levels of MCT2, which takes up lactate in neurons, increased in the brain, as did muscle MCTs. Metabolomics revealed that brain, but not muscle, ATP was maintained with lactate and other glycogenolytic/glycolytic sources. Intracerebroventricular injection of the glycogen phosphorylase inhibitor 1,4-dideoxy-1,4-imino-d-arabinitol did not affect peripheral glycemic conditions but suppressed brain lactate production and decreased hippocampal ATP levels at exhaustion. An MCT2 inhibitor, α-cyano-4-hydroxy-cinnamate, triggered a similar response that resulted in lower endurance capacity. These findings provide direct evidence for the energetic role of astrocytic glycogen-derived lactate in the exhaustive-exercising brain, implicating the significance of brain glycogen level in endurance capacity. Glycogen-maintained ATP in the brain is a possible defense mechanism for neurons in the exhausted brain.

  14. Low-carbohydrate diet induces metabolic depression: a possible mechanism to conserve glycogen.

    Science.gov (United States)

    Winwood-Smith, Hugh S; Franklin, Craig E; White, Craig R

    2017-10-01

    Long-term studies have found that low-carbohydrate diets are more effective for weight loss than calorie-restricted diets in the short term but equally or only marginally more effective in the long term. Low-carbohydrate diets have been linked to reduced glycogen stores and increased feelings of fatigue. We propose that reduced physical activity in response to lowered glycogen explains the diminishing weight loss advantage of low-carbohydrate compared with low-calorie diets over longer time periods. We explored this possibility by feeding adult Drosophila melanogaster a standard or a low-carbohydrate diet for 9 days and measured changes in metabolic rate, glycogen stores, activity, and body mass. We hypothesized that a low-carbohydrate diet would cause a reduction in glycogen stores, which recover over time, a reduction in physical activity, and an increase in resting metabolic rate. The low-carbohydrate diet reduced glycogen stores, which recovered over time. Activity was unaffected by diet, but metabolic rate was reduced, in the low-carbohydrate group. We conclude that metabolic depression could explain the decreased effectiveness of low-carbohydrate diets over time and recommend further investigation of long-term metabolic effects of dietary interventions and a greater focus on physiological plasticity within the study of human nutrition. Copyright © 2017 the American Physiological Society.

  15. 13C Mrs Studies of the Control of Hepatic Glycogen Metabolism at High Magnetic Fields

    Science.gov (United States)

    Miller, Corin O.; Cao, Jin; Zhu, He; Chen, Li M.; Wilson, George; Kennan, Richard; Gore, John C.

    2017-06-01

    Introduction: Glycogen is the primary intracellular storage form of carbohydrates. In contrast to most tissues where stored glycogen can only supply the local tissue with energy, hepatic glycogen is mobilized and released into the blood to maintain appropriate circulating glucose levels, and is delivered to other tissues as glucose in response to energetic demands. Insulin and glucagon, two current targets of high interest in the pharmaceutical industry, are well known glucose-regulating hormones whose primary effect in liver is to modulate glycogen synthesis and breakdown. The purpose of these studies was to develop methods to measure glycogen metabolism in real time non-invasively both in isolated mouse livers, and in non-human primates (NHPs) using 13C MRS. Methods: Livers were harvested from C57/Bl6 mice and perfused with [1-13C] Glucose. To demonstrate the ability to measure acute changes in glycogen metabolism ex-vivo, fructose, glucagon, and insulin were administered to the liver ex-vivo. The C1 resonance of glycogen was measured in real time with 13C MRS using an 11.7T (500 MHz) NMR spectrometer. To demonstrate the translatability of this approach, NHPs (male rhesus monkeys) were studied in a 7 T Philips MRI using a partial volume 1H/13C imaging coil. NPHs were subjected to a variable IV infusion of [1-13C] glucose (to maintain blood glucose at 3-4x basal), along with a constant 1 mg/kg/min infusion of fructose. The C1 resonance of glycogen was again measured in real time with 13C MRS. To demonstrate the ability to measure changes in glycogen metabolism in vivo, animals received a glucagon infusion (1 μg/kg bolus followed by 40 ng/kg/min constant infusion) half way through the study on the second study session. Results: In both perfused mouse livers and in NHPs, hepatic 13C-glycogen synthesis (i.e. monotonic increases in the 13C-glycogen NMR signal) was readily detected. In both paradigms, addition of glucagon resulted in cessation of glycogen synthesis

  16. Dietary Tools To Modulate Glycogen Storage in Gilthead Seabream Muscle: Glycerol Supplementation

    DEFF Research Database (Denmark)

    Silva, Tomé S.; Matos, Elisabete; Cordeiro, Odete D.

    2012-01-01

    The quality and shelf life of fish meat products depend on the skeletal muscle’s energetic state at slaughter, as meat decomposition processes can be exacerbated by energy depletion. In this study, we tested dietary glycerol as a way of replenishing muscle glycogen reserves of farmed gilthead......, and organoleptic properties (aroma and color). Proteomic analysis showed a low impact of glycerol-supplementation on muscle metabolism, with most changes probably reflecting increased stress coping capacity in glycerol-fed fish. This suggests inclusion of crude glycerol in gilthead seabream diets (particularly...

  17. Glycogen synthesis in glycogenin 1-deficient patients

    DEFF Research Database (Denmark)

    Krag, Thomas O.; Ruiz-Ruiz, Cristina; Vissing, John

    2017-01-01

    Context: Glycogen storage disease (GSD) type XV is a rare disease caused by mutations in the GYG1 gene that codes for the core molecule of muscle glycogen, glycogenin 1. Nonetheless, glycogen is present in muscles of glycogenin 1-deficient patients, suggesting an alternative for glycogen buildup....... A likely candidate is glycogenin 2, an isoform expressed in the liver and heart but not in healthy skeletal muscle. Objective: We wanted to investigate the formation of glycogen and changes in glycogen metabolism in patients with GSD type XV. Design, Setting, and Patients: Two patients with mutations...... in the GYG1 gene were investigated for histopathology, ultrastructure, and expression of proteins involved in glycogen synthesis and metabolism. Results: Apart from occurrence of polyglucosan (PG) bodies in few fibers, glycogen appeared normal in most cells, and the concentration was normal in patients...

  18. Swelling of rat hepatocytes stimulates glycogen synthesis

    NARCIS (Netherlands)

    Baquet, A.; Hue, L.; Meijer, A. J.; van Woerkom, G. M.; Plomp, P. J.

    1990-01-01

    In hepatocytes from fasted rats, several amino acids are known to stimulate glycogen synthesis via activation of glycogen synthase. The hypothesis that an increase in cell volume resulting from amino acid uptake may be involved in the stimulation of glycogen synthesis is supported by the following

  19. The subcellular localization of yeast glycogen synthase is dependent upon glycogen content

    OpenAIRE

    Wilson, Wayne A.; Boyer, Michael P.; Davis, Keri D.; Burke, Michael; Roach, Peter J.

    2010-01-01

    The budding yeast, Saccharomyces cerevisiae, accumulates the storage polysaccharide glycogen in response to nutrient limitation. Glycogen synthase, the major form of which is encoded by the GSY2 gene, catalyzes the key regulated step in glycogen storage. Here, we utilize Gsy2p fusions to green fluorescent protein (GFP) to determine where glycogen synthase is located within cells. We demonstrate that the localization pattern of Gsy2-GFP depends upon the glycogen content of the cell. When glyco...

  20. Harvesting and replenishment policies for renewable natural resources

    Science.gov (United States)

    Douglas, Aaron J.; Johnson, Richard L.

    1993-01-01

    The current paper links the optimal intertemporal use of renewable natural resources to the harvesting activities of various economic agents. Previous contributions cite market forces as a causative factor inducing the extirpation of renewable natural resources. The analysis given here discusses investment in the stock of renewable resources and cites important examples of this activity. By introducing joint harvesting and replenishment strategies into a model of renewable resource use, the analysis adds descriptive reality and relevance to positive and normative discussions of renewable natural resource use. A high price for the yield or a high discount rate tend to diminish the size of the optimum stationary stock of the resource with a non-replenishment harvesting strategy. Optimal non-replenishment harvesting strategies for renewable natural resources will exhaustion or extirpation of the resource if the price of the yield or the discount rate are sufficiently large. However, the availability of a replenishment technology and the use of replenishment activities tends to buffer the resource against exhaustion or extirpation.

  1. Physiological aspects of the subcellular localization of glycogen in skeletal muscle

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Ørtenblad, Niels

    2013-01-01

    Glucose is stored in skeletal muscle fibers as glycogen, a branched-chain polymer observed in electron microscopy images as roughly spherical particles (known as β-particles of 10-45 nm in diameter), which are distributed in distinct localizations within the myofibers and are physically associated...... investigated the role and regulation of these distinct deposits of glycogen. In this report, we review the available literature regarding the subcellular localization of glycogen in skeletal muscle as investigated by electron microscopy studies and put this into perspective in terms of the architectural......, topological, and dynamic organization of skeletal muscle fibers. In summary, the distribution of glycogen within skeletal muscle fibers has been shown to depend on the fiber phenotype, individual training status, short-term immobilization, and exercise and to influence both muscle contractility...

  2. Glucose balance and muscle glycogen during TPN in the early post-operative phase

    DEFF Research Database (Denmark)

    Henneberg, S; Stjernström, H; Essén-Gustavsson, B

    1985-01-01

    In order to study how muscle glycogen is influenced by different nutritional regimens in the early post-operative period we took muscle biopsies from 20 patients preoperatively and on the fourth post-operative day after abdominal aortic surgery. Ten patients received 93% of non-protein energy......-production) were performed and from these data glucose balance was calculated as the difference between glucose intake and glucose expenditure. Muscle biopsies were analysed for glycogen, adenosine triphosphate, glucose-6-phosphate, lactate and citrate. We found that it was possible to maintain muscle...... glycogen stores at pre-operative levels with a glucose-insulin regimen. With the fat regimen there was a 31% decrease in muscle glycogen and two patients had a negative glucose balance despite the fact that 150 g of glucose were given. Average glucose balance throughout the study correlated positively...

  3. Protein targeting to glycogen is a master regulator of glycogen synthesis in astrocytes

    KAUST Repository

    Ruchti, E.

    2016-10-08

    The storage and use of glycogen, the main energy reserve in the brain, is a metabolic feature of astrocytes. Glycogen synthesis is regulated by Protein Targeting to Glycogen (PTG), a member of specific glycogen-binding subunits of protein phosphatase-1 (PPP1). It positively regulates glycogen synthesis through de-phosphorylation of both glycogen synthase (activation) and glycogen phosphorylase (inactivation). In cultured astrocytes, PTG mRNA levels were previously shown to be enhanced by the neurotransmitter noradrenaline. To achieve further insight into the role of PTG in the regulation of astrocytic glycogen, its levels of expression were manipulated in primary cultures of mouse cortical astrocytes using adenovirus-mediated overexpression of tagged-PTG or siRNA to downregulate its expression. Infection of astrocytes with adenovirus led to a strong increase in PTG expression and was associated with massive glycogen accumulation (>100 fold), demonstrating that increased PTG expression is sufficient to induce glycogen synthesis and accumulation. In contrast, siRNA-mediated downregulation of PTG resulted in a 2-fold decrease in glycogen levels. Interestingly, PTG downregulation strongly impaired long-term astrocytic glycogen synthesis induced by insulin or noradrenaline. Finally, these effects of PTG downregulation on glycogen metabolism could also be observed in cultured astrocytes isolated from PTG-KO mice. Collectively, these observations point to a major role of PTG in the regulation of glycogen synthesis in astrocytes and indicate that conditions leading to changes in PTG expression will directly impact glycogen levels in this cell type.

  4. Putative role of glycogen as a peripheral biomarker of GSK3β activity.

    Science.gov (United States)

    Frizzo, Marcos Emilio

    2013-09-01

    GSK3β expression were upregulated by continuous treatment with sertraline. Here, we hypothesized that the quantification of glycogen in platelets might be used as a peripheral biomarker of GSK3β activity. Since it has been recently demonstrated that the modulation of GSK3β activity causes changes in glycogen stores, the glycogen levels in platelets could be used to assay the effects of drugs that have this kinase as a target, or diseases where its activity is affected. In conclusion, we hypothesized that the determination of glycogen peripherally may be useful to indicate a change in the activity of this enzyme, providing a faster and non-invasive approach to guide the therapeutic procedures for the patient. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Glycogen resynthesis rate following cross-country skiing is closely correlated to skeletal muscle glycogen content

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Nielsen, Joachim; Saltin, Bengt

    on an optimal glycogen resynthesis rate before a subsequent exercise session. The purpose of present study was to evaluate the glycogen resynthesis rate in elite cross-country (cc) skiers, following exhaustive exercise, and to examine the role of muscular glycogen content on the resynthesis rate. METHOD: Ten...... as 4h and 22h after the race and analyzed for glycogen content. Figure 1. Correlation between muscle glycogen resynthesis rate and glycogen content after and in the rocery period after exercise. Line indicate best fit of all the data points (r2 = 0.41, p

  6. Joint pricing and inventory replenishment decisions with returns and expediting

    NARCIS (Netherlands)

    Zhu, Stuart X.

    2012-01-01

    We study a single-item periodic-review model for the joint pricing and inventory replenishment problem with returns and expediting. Demand in consecutive periods are independent random variables and their distributions are price sensitive. At the end of each period, after the demand is realized, a

  7. Computing replenishment cycle policy parameters for a perishable item

    NARCIS (Netherlands)

    Rossi, R.; Tarim, S.A.; Hnich, B.; Prestwich, S.

    2010-01-01

    In many industrial environments there is a significant class of problems for which the perishable nature of the inventory cannot be ignored in developing replenishment order plans. Food is the most salient example of a perishable inventory item. In this work, we consider the periodic-review,

  8. Output synchronization control of ship replenishment operations: theory and experiments

    NARCIS (Netherlands)

    Kyrkjebø, E.; Pettersen, K.Y.; Wondergem, M.; Nijmeijer, H.

    2007-01-01

    A leader–follower synchronization output feedback control scheme is presented for the ship replenishment problem where only positions are measured. No mathematical model of the leader ship is required, and the control scheme relies on nonlinear observers to estimate velocity and acceleration of all

  9. Rolling-horizon replenishment : Policies and performance analysis

    NARCIS (Netherlands)

    Lian, Z.; Liu, L.; Zhu, Stuart X.

    We consider a rolling-horizon (RH) replenishment modeling framework under which a buyer can update demand information and inventory status, modify order quantities committed previously, place an advanced order for a new period at the end of the RH, and move along in time seamlessly. We show that the

  10. A whole-body model for glycogen regulation reveals a critical role for substrate cycling in maintaining blood glucose homeostasis.

    Directory of Open Access Journals (Sweden)

    Ke Xu

    2011-12-01

    Full Text Available Timely, and sometimes rapid, metabolic adaptation to changes in food supply is critical for survival as an organism moves from the fasted to the fed state, and vice versa. These transitions necessitate major metabolic changes to maintain energy homeostasis as the source of blood glucose moves away from ingested carbohydrates, through hepatic glycogen stores, towards gluconeogenesis. The integration of hepatic glycogen regulation with extra-hepatic energetics is a key aspect of these adaptive mechanisms. Here we use computational modeling to explore hepatic glycogen regulation under fed and fasting conditions in the context of a whole-body model. The model was validated against previous experimental results concerning glycogen phosphorylase a (active and glycogen synthase a dynamics. The model qualitatively reproduced physiological changes that occur during transition from the fed to the fasted state. Analysis of the model reveals a critical role for the inhibition of glycogen synthase phosphatase by glycogen phosphorylase a. This negative regulation leads to high levels of glycogen synthase activity during fasting conditions, which in turn increases substrate (futile cycling, priming the system for a rapid response once an external source of glucose is restored. This work demonstrates that a mechanistic understanding of the design principles used by metabolic control circuits to maintain homeostasis can benefit from the incorporation of mathematical descriptions of these networks into "whole-body" contextual models that mimic in vivo conditions.

  11. Lafora disease offers a unique window into neuronal glycogen metabolism.

    Science.gov (United States)

    Gentry, Matthew S; Guinovart, Joan J; Minassian, Berge A; Roach, Peter J; Serratosa, Jose M

    2018-05-11

    Lafora disease (LD) is a fatal, autosomal recessive, glycogen-storage disorder that manifests as severe epilepsy. LD results from mutations in the gene encoding either the glycogen phosphatase laforin or the E3 ubiquitin ligase malin. Individuals with LD develop cytoplasmic, aberrant glycogen inclusions in nearly all tissues that more closely resemble plant starch than human glycogen. This Minireview discusses the unique window into glycogen metabolism that LD research offers. It also highlights recent discoveries, including that glycogen contains covalently bound phosphate and that neurons synthesize glycogen and express both glycogen synthase and glycogen phosphorylase. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Review: Alterations in placental glycogen deposition in complicated pregnancies: Current preclinical and clinical evidence.

    Science.gov (United States)

    Akison, Lisa K; Nitert, Marloes Dekker; Clifton, Vicki L; Moritz, Karen M; Simmons, David G

    2017-06-01

    Normal placental function is essential for optimal fetal growth. Transport of glucose from mother to fetus is critical for fetal nutrient demands and can be stored in the placenta as glycogen. However, the function of this glycogen deposition remains a matter of debate: It could be a source of fuel for the placenta itself or a storage reservoir for later use by the fetus in times of need. While the significance of placental glycogen remains elusive, mounting evidence indicates that altered glycogen metabolism and/or deposition accompanies many pregnancy complications that adversely affect fetal development. This review will summarize histological, biochemical and molecular evidence that glycogen accumulates in a) placentas from a variety of experimental rodent models of perturbed pregnancy, including maternal alcohol exposure, glucocorticoid exposure, dietary deficiencies and hypoxia and b) placentas from human pregnancies with complications including preeclampsia, gestational diabetes mellitus and intrauterine growth restriction (IUGR). These pregnancies typically result in altered fetal growth, developmental abnormalities and/or disease outcomes in offspring. Collectively, this evidence suggests that changes in placental glycogen deposition is a common feature of pregnancy complications, particularly those associated with altered fetal growth. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  13. Ultrastructure and cytochemistry of cardiac intramitochondrial glycogen.

    Science.gov (United States)

    Sótonyi, P; Somogyi, E; Nemes, A; Juhász-Nagy, S

    1976-01-01

    Authors have observed abnormalities of glycogen localization in cardiac muscle, after normothermic cardiac arrest. The identification of these intramitrochondrial particles as glycogen was confirmed by selective staining with periodic acid-lead citrat, periodic acid-thiosemicarbazide protein methods and by their selective removal from tissue sections by alfa-amylase. The intramitochondrial glycogen particles were of beta-type. Some intramitochondrial particles were surrounded by paired membranes which resulted from protrusion of parts of mitochondrial membrane.

  14. Determination of the Glycogen Content in Cyanobacteria.

    Science.gov (United States)

    De Porcellinis, Alice; Frigaard, Niels-Ulrik; Sakuragi, Yumiko

    2017-07-17

    Cyanobacteria accumulate glycogen as a major intracellular carbon and energy storage during photosynthesis. Recent developments in research have highlighted complex mechanisms of glycogen metabolism, including the diel cycle of biosynthesis and catabolism, redox regulation, and the involvement of non-coding RNA. At the same time, efforts are being made to redirect carbon from glycogen to desirable products in genetically engineered cyanobacteria to enhance product yields. Several methods are used to determine the glycogen contents in cyanobacteria, with variable accuracies and technical complexities. Here, we provide a detailed protocol for the reliable determination of the glycogen content in cyanobacteria that can be performed in a standard life science laboratory. The protocol entails the selective precipitation of glycogen from the cell lysate and the enzymatic depolymerization of glycogen to generate glucose monomers, which are detected by a glucose oxidase-peroxidase (GOD-POD) enzyme coupled assay. The method has been applied to Synechocystis sp. PCC 6803 and Synechococcus sp. PCC 7002, two model cyanobacterial species that are widely used in metabolic engineering. Moreover, the method successfully showed differences in the glycogen contents between the wildtype and mutants defective in regulatory elements or glycogen biosynthetic genes.

  15. Refeeding-induced brown adipose tissue glycogen hyper-accumulation in mice is mediated by insulin and catecholamines.

    Directory of Open Access Journals (Sweden)

    Christopher M Carmean

    Full Text Available Brown adipose tissue (BAT generates heat during adaptive thermogenesis through a combination of oxidative metabolism and uncoupling protein 1-mediated electron transport chain uncoupling, using both free-fatty acids and glucose as substrate. Previous rat-based work in 1942 showed that prolonged partial fasting followed by refeeding led to a dramatic, transient increase in glycogen stores in multiple fat depots. In the present study, the protocol was replicated in male CD1 mice, resulting in a 2000-fold increase in interscapular BAT (IBAT glycogen levels within 4-12 hours (hr of refeeding, with IBAT glycogen stores reaching levels comparable to fed liver glycogen. Lesser effects occurred in white adipose tissues (WAT. Over the next 36 hr, glycogen levels dissipated and histological analysis revealed an over-accumulation of lipid droplets, suggesting a potential metabolic connection between glycogenolysis and lipid synthesis. 24 hr of total starvation followed by refeeding induced a robust and consistent glycogen over-accumulation similar in magnitude and time course to the prolonged partial fast. Experimentation demonstrated that hyperglycemia was not sufficient to drive glycogen accumulation in IBAT, but that elevated circulating insulin was sufficient. Additionally, pharmacological inhibition of catecholamine production reduced refeeding-induced IBAT glycogen storage, providing evidence of a contribution from the central nervous system. These findings highlight IBAT as a tissue that integrates both canonically-anabolic and catabolic stimulation for the promotion of glycogen storage during recovery from caloric deficit. The preservation of this robust response through many generations of animals not subjected to food deprivation suggests that the over-accumulation phenomenon plays a critical role in IBAT physiology.

  16. Refeeding-Induced Brown Adipose Tissue Glycogen Hyper-Accumulation in Mice Is Mediated by Insulin and Catecholamines

    Science.gov (United States)

    Carmean, Christopher M.; Bobe, Alexandria M.; Yu, Justin C.; Volden, Paul A.; Brady, Matthew J.

    2013-01-01

    Brown adipose tissue (BAT) generates heat during adaptive thermogenesis through a combination of oxidative metabolism and uncoupling protein 1-mediated electron transport chain uncoupling, using both free-fatty acids and glucose as substrate. Previous rat-based work in 1942 showed that prolonged partial fasting followed by refeeding led to a dramatic, transient increase in glycogen stores in multiple fat depots. In the present study, the protocol was replicated in male CD1 mice, resulting in a 2000-fold increase in interscapular BAT (IBAT) glycogen levels within 4–12 hours (hr) of refeeding, with IBAT glycogen stores reaching levels comparable to fed liver glycogen. Lesser effects occurred in white adipose tissues (WAT). Over the next 36 hr, glycogen levels dissipated and histological analysis revealed an over-accumulation of lipid droplets, suggesting a potential metabolic connection between glycogenolysis and lipid synthesis. 24 hr of total starvation followed by refeeding induced a robust and consistent glycogen over-accumulation similar in magnitude and time course to the prolonged partial fast. Experimentation demonstrated that hyperglycemia was not sufficient to drive glycogen accumulation in IBAT, but that elevated circulating insulin was sufficient. Additionally, pharmacological inhibition of catecholamine production reduced refeeding-induced IBAT glycogen storage, providing evidence of a contribution from the central nervous system. These findings highlight IBAT as a tissue that integrates both canonically-anabolic and catabolic stimulation for the promotion of glycogen storage during recovery from caloric deficit. The preservation of this robust response through many generations of animals not subjected to food deprivation suggests that the over-accumulation phenomenon plays a critical role in IBAT physiology. PMID:23861810

  17. Role of the direct and indirect pathways for glycogen synthesis in rat liver in the postprandial state

    International Nuclear Information System (INIS)

    Huang, M.T.; Veech, R.L.

    1988-01-01

    The pathway for hepatic glycogen synthesis in the postprandial state was studied in meal-fed rats chronically cannulated in the portal vein. Plasma glucose concentration in the portal vein was found to be 4.50 +/- 1.01 mM (mean +/- SE; n = 3) before a meal and 11.54 +/- 0.70 mM (mean +/- SE; n = 4) after a meal in rats meal-fed a diet consisting of 100% commercial rat chow for 7 d. The hepatic-portal difference of plasma glucose concentration showed that liver released glucose in the fasted state and either extracted or released glucose after feeding depending on plasma glucose concentration in the portal vein. The concentration of portal vein glucose at which liver changes from glucose releasing to glucose uptake was 8 mM, the Km of glucokinase. The rate of glycogen synthesis in liver during meal-feeding was found to be approximately 1 mumol glucosyl U/g wet wt/min in rats meal-fed a 50% glucose supplemented chow diet. The relative importance of the direct vs. indirect pathway for the replenishment of hepatic glycogen was determined by the incorporation of [3- 3 H,U- 14 C]glucose into liver glycogen. Labeled glucose was injected into the portal vein at the end of meal-feeding. The ratio of 3 H/ 14 C in the glucosyl units of glycogen was found to be 83-92% of the ratio in liver free glucose six minutes after the injection, indicating that the majority of exogenous glucose incorporated into glycogen did not go through glycolysis. The percent contribution of the direct versus indirect pathway was quantitated from the difference in the relative specific activity (RSA) of [ 3 H] and [ 14 C]-glycogen in rats infused with [3- 3 H,U- 14 C]glucose. No significant difference was found between the RSA of [ 3 H]glycogen and [ 14 C]glycogen, indicating further that the pathway for glycogen synthesis in liver from exogenous glucose is from the direct pathway

  18. Genetics Home Reference: glycogen storage disease type VII

    Science.gov (United States)

    ... Home Health Conditions Glycogen storage disease type VII Glycogen storage disease type VII Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Glycogen storage disease type VII (GSDVII) is an inherited ...

  19. Genetics Home Reference: glycogen storage disease type IV

    Science.gov (United States)

    ... Home Health Conditions Glycogen storage disease type IV Glycogen storage disease type IV Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Glycogen storage disease type IV (GSD IV) is an ...

  20. Muscle glycogen storage after different amounts of carbohydrate ingestion.

    Science.gov (United States)

    Ivy, J L; Lee, M C; Brozinick, J T; Reed, M J

    1988-11-01

    The purpose of this study was to determine whether the rate of muscle glycogen storage could be enhanced during the initial 4-h period postexercise by substantially increasing the amount of the carbohydrate consumed. Eight subjects cycled for 2 h on three separate occasions to deplete their muscle glycogen stores. Immediately and 2 h after exercise they consumed either 0 (P), 1.5 (L), or 3.0 g glucose/kg body wt (H) from a 50% glucose polymer solution. Blood samples were drawn from an antecubital vein before exercise, during exercise, and throughout recovery. Muscle biopsies were taken from the vastus lateralis immediately, 2 h, and 4 h after exercise. Blood glucose and insulin declined significantly during exercise in each of the three treatments. They remained below the preexercise concentrations during recovery in the P treatment but increased significantly above the preexercise concentrations during the L and H treatments. By the end of the 4 h-recovery period, blood glucose and insulin were still significantly above the preexercise concentrations in both treatments. Muscle glycogen storage was significantly increased above the basal rate (P, 0.5 mumol.g wet wt-1.h-1) after ingestion of either glucose polymer supplement. The rates of muscle glycogen storage, however, were not different between the L and H treatments during the first 2 h (L, 5.2 +/- 0.9 vs. H, 5.8 +/- 0.7 mumol.g wet wt-1.h-1) or the second 2 h of recovery (L, 4.0 +/- 0.9 vs. H, 4.5 +/- 0.6 mumol.g wet wt-1. h-1).(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Replenishing data descriptors in a DMA injection FIFO buffer

    Science.gov (United States)

    Archer, Charles J [Rochester, MN; Blocksome, Michael A [Rochester, MN; Cernohous, Bob R [Rochester, MN; Heidelberger, Philip [Cortlandt Manor, NY; Kumar, Sameer [White Plains, NY; Parker, Jeffrey J [Rochester, MN

    2011-10-11

    Methods, apparatus, and products are disclosed for replenishing data descriptors in a Direct Memory Access (`DMA`) injection first-in-first-out (`FIFO`) buffer that include: determining, by a messaging module on an origin compute node, whether a number of data descriptors in a DMA injection FIFO buffer exceeds a predetermined threshold, each data descriptor specifying an application message for transmission to a target compute node; queuing, by the messaging module, a plurality of new data descriptors in a pending descriptor queue if the number of the data descriptors in the DMA injection FIFO buffer exceeds the predetermined threshold; establishing, by the messaging module, interrupt criteria that specify when to replenish the injection FIFO buffer with the plurality of new data descriptors in the pending descriptor queue; and injecting, by the messaging module, the plurality of new data descriptors into the injection FIFO buffer in dependence upon the interrupt criteria.

  2. Solution Methods for the Periodic Petrol Station Replenishment Problem

    OpenAIRE

    C Triki

    2013-01-01

    In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP) over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ens...

  3. Partial podocyte replenishment in experimental FSGS derives from nonpodocyte sources.

    Science.gov (United States)

    Kaverina, Natalya V; Eng, Diana G; Schneider, Remington R S; Pippin, Jeffrey W; Shankland, Stuart J

    2016-06-01

    The current studies used genetic fate mapping to prove that adult podocytes can be partially replenished following depletion. Inducible NPHS2-rtTA/tetO-Cre/RS-ZsGreen-R reporter mice were generated to permanently label podocytes with the ZsGreen reporter. Experimental focal segmental glomerulosclerosis (FSGS) was induced with a cytotoxic podocyte antibody. On FSGS day 7, immunostaining for the podocyte markers p57, synaptopodin, and podocin were markedly decreased by 44%, and this was accompanied by a decrease in ZsGreen fluorescence. The nuclear stain DAPI was absent in segments of reduced ZsGreen and podocyte marker staining, which is consistent with podocyte depletion. Staining for p57, synaptopodin, podocin, and DAPI increased at FSGS day 28 and was augmented by the ACE inhibitor enalapril, which is consistent with a partial replenishment of podocytes. In contrast, ZsGreen fluorescence did not return and remained significantly low at day 28, indicating replenishment was from a nonpodocyte origin. Despite administration of bromodeoxyuridine (BrdU) thrice weekly throughout the course of disease, BrdU staining was not detected in podocytes, which is consistent with an absence of proliferation. Although ZsGreen reporting was reduced in the tuft at FSGS day 28, labeled podocytes were detected along the Bowman's capsule in a subset of glomeruli, which is consistent with migration from the tuft. Moreover, more than half of the migrated podocytes coexpressed the parietal epithelial cell (PEC) proteins claudin-1, SSeCKS, and PAX8. These results show that although podocytes can be partially replenished following abrupt depletion, a process augmented by ACE inhibition, the source or sources are nonpodocyte in origin and are independent of proliferation. Furthermore, a subset of podocytes migrate to the Bowman's capsule and begin to coexpress PEC markers. Copyright © 2016 the American Physiological Society.

  4. Merchandise and Replenishment Planning Optimisation for Fashion Retail

    Directory of Open Access Journals (Sweden)

    Raffaele Iannone

    2013-08-01

    Full Text Available The integration among different companies functions, collaborative planning and the elaboration of focused distribution plans are critical to the success of each kind of company working in the complex retail sector. In this contest, the present work proposes the description of a model able to support coordinated strategic choices continually made by Supply Chain (SC actors. The final objective is achievement of the full optimisation of Merchandise & Replenishment Planning phases, identifying the right replenishment quantities and periods. To test the proposed model’s effectiveness, it was applied to an important Italian fashion company in the complex field of fast-fashion, a sector in which promptness is a main competitive leverage and, therefore, the planning cannot exclude the time variable. The passage from a total push strategy, currently used by the company, to a push-pull one, suggested by the model, allowed us not only to estimate a reduction in goods quantities to purchase at the beginning of a sales period (with considerable economic savings, but also elaborate a focused replenishment plan that permits reduction and optimisation of departures from network warehouses to Points of Sale (POS.

  5. Threonine phosphorylation of rat liver glycogen synthase

    International Nuclear Information System (INIS)

    Arino, J.; Arro, M.; Guinovart, J.J.

    1985-01-01

    32 P-labeled glycogen synthase specifically immunoprecipitated from 32 P-phosphate incubated rat hepatocytes contains, in addition to [ 32 P] phosphoserine, significant levels of [ 32 P] phosphothreonine. When the 32 P-immunoprecipitate was cleaved with CNBr, the [ 32 P] phosphothreonine was recovered in the large CNBr fragment (CB-2, Mapp 28 Kd). Homogeneous rat liver glycogen synthase was phosphorylated by all the protein kinases able to phosphorylate CB-2 in vitro. After analysis of the immunoprecipitated enzyme for phosphoaminoacids, it was observed that only casein kinase II was able to phosphorylate on threonine and 32 P-phosphate was only found in CB-2. These results demonstrate that rat liver glycogen synthase is phosphorylated at threonine site(s) contained in CB-2 and strongly indicate that casein kinase II may play a role in the ''in vivo'' phosphorylation of liver glycogen synthase. This is the first protein kinase reported to phosphorylate threonine residues in liver glycogen synthase

  6. Trehalose, glycogen and ethanol metabolism in the gcr1 mutant of Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Seker, Tamay; Hamamci, H.

    2003-01-01

    Since Gcr1p is pivotal in controlling the transcription of glycolytic enzymes and trehalose metabolism seems to be one of the control points of glycolysis, we examined trehalose and glycogen synthesis in response to 2 % glucose pulse during batch growth in gcr1 (glucose regulation-1) mutant lacking...... fully functional glycolytic pathway and in the wild-type strain. An increase in both trehalose and glycogen stores was observed 1 and 2 h after the pulse followed by a steady decrease in both the wild-type and the gcr1 mutant. The accumulation was faster while the following degradation was slower in gcr......1 cells compared to wild-type ones. Although there was no distinct glucose consumption in the mutant cells it seemed that the glucose repression mechanism is similar in gcr1 mutant and in wild-type strain at least with respect to trehalose and glycogen metabolism....

  7. Posthemorrhage glycogen and lactate metabolism in the liver: an experimental study with postprandial rats

    International Nuclear Information System (INIS)

    Boija, P.O.; Nylander, G.; Suhaili, A.; Ware, J.

    1988-01-01

    Glycogen and lactate metabolism was studied in livers from three groups of postprandial rats sustaining 70 mm Hg hemorrhagic hypotension for variable periods, 60 min (60H group), 120 min (120H group), and nonbled controls. The donor livers were investigated after completed hemorrhage using an in vitro perfusion system with L-lactate as substrate, together with U- 14 C-lactate. The residual glycogen stores were determined after perfusions. The incorporation of labelled lactate to glucose was increased in the 120H group by 66.7% and 116.8% compared to the 60H group and controls (p less than 0.01), but glycogenolysis was still the main source of glucose released in the 120H group. Glycogen formation from labelled lactate was 46.6% higher in the 120H group compared to controls (p less than 0.05) and lactate oxidation was decreased by 67.5% (p less than 0.05). The data suggest that hepatocytes are capable of rapid change from glycolysis to gluconeogenesis during hemorrhagic hypovolemia. However, energy-sparing glycogen breakdown is given priority over gluconeogenesis as long as glycogen remains available

  8. Astrocyte glycogen as an emergency fuel under conditions of glucose deprivation or intense neural activity.

    Science.gov (United States)

    Brown, Angus M; Ransom, Bruce R

    2015-02-01

    Energy metabolism in the brain is a complex process that is incompletely understood. Although glucose is agreed as the main energy support of the brain, the role of glucose is not clear, which has led to controversies that can be summarized as follows: the fate of glucose, once it enters the brain is unclear. It is not known the form in which glucose enters the cells (neurons and glia) within the brain, nor the degree of metabolic shuttling of glucose derived metabolites between cells, with a key limitation in our knowledge being the extent of oxidative metabolism, and how increased tissue activity alters this. Glycogen is present within the brain and is derived from glucose. Glycogen is stored in astrocytes and acts to provide short-term delivery of substrates to neural elements, although it may also contribute an important component to astrocyte metabolism. The roles played by glycogen awaits further study, but to date its most important role is in supporting neural elements during increased firing activity, where signaling molecules, proposed to be elevated interstitial K(+), indicative of elevated neural firing rates, activate glycogen phosphorylase leading to increased production of glycogen derived substrate.

  9. Predaceous ants, beach replenishment, and nest placement by sea turtles.

    Science.gov (United States)

    Wetterer, James K; Wood, Lawrence D; Johnson, Chris; Krahe, Holly; Fitchett, Stephanie

    2007-10-01

    Ants known for attacking and killing hatchling birds and reptiles include the red imported fire ant (Solenopsis invicta Buren), tropical fire ant [Solenopsis geminata (Fabr.)], and little fire ant [Wasmannia auropunctata (Roger)]. We tested whether sea turtle nest placement influenced exposure to predaceous ants. In 2000 and 2001, we surveyed ants along a Florida beach where green turtles (Chelonia mydas L.), leatherbacks (Dermochelys coriacea Vandelli), and loggerheads (Caretta caretta L.) nest. Part of the beach was artificially replenished between our two surveys. As a result, mean beach width experienced by nesting turtles differed greatly between the two nesting seasons. We surveyed 1,548 sea turtle nests (2000: 909 nests; 2001: 639 nests) and found 22 ant species. S. invicta was by far the most common species (on 431 nests); S. geminata and W. auropunctata were uncommon (on 3 and 16 nests, respectively). In 2000, 62.5% of nests had ants present (35.9% with S. invicta), but in 2001, only 30.5% of the nests had ants present (16.4% with S. invicta). Turtle nests closer to dune vegetation had significantly greater exposure to ants. Differences in ant presence on turtle nests between years and among turtle species were closely related to differences in nest placement relative to dune vegetation. Beach replenishment significantly lowered exposure of nests to ants because on the wider beaches turtles nested farther from the dune vegetation. Selective pressures on nesting sea turtles are altered both by the presence of predaceous ants and the practice of beach replenishment.

  10. Astrocyte glycogen and brain energy metabolism.

    Science.gov (United States)

    Brown, Angus M; Ransom, Bruce R

    2007-09-01

    The brain contains glycogen but at low concentration compared with liver and muscle. In the adult brain, glycogen is found predominantly in astrocytes. Astrocyte glycogen content is modulated by a number of factors including some neurotransmitters and ambient glucose concentration. Compelling evidence indicates that astrocyte glycogen breaks down during hypoglycemia to lactate that is transferred to adjacent neurons or axons where it is used aerobically as fuel. In the case of CNS white matter, this source of energy can extend axon function for 20 min or longer. Likewise, during periods of intense neural activity when energy demand exceeds glucose supply, astrocyte glycogen is degraded to lactate, a portion of which is transferred to axons for fuel. Astrocyte glycogen, therefore, offers some protection against hypoglycemic neural injury and ensures that neurons and axons can maintain their function during very intense periods of activation. These emerging principles about the roles of astrocyte glycogen contradict the long held belief that this metabolic pool has little or no functional significance.

  11. Carcass glycogen repletion on carbohydrate re-feeding after starvation.

    OpenAIRE

    Cox, D J; Palmer, T N

    1987-01-01

    In mice, the response of carcass glycogen to glucose re-feeding after starvation is biphasic. The initial repletive phase is followed by partial (greater than 50%) glycogen mobilization. This turnover of carcass glycogen in response to carbohydrate re-feeding may play an important role in the provision of C3 precursors for hepatic glycogen synthesis.

  12. Solution Methods for the Periodic Petrol Station Replenishment Problem

    Directory of Open Access Journals (Sweden)

    C Triki

    2013-12-01

    Full Text Available In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ensuring a better quality solution. Our heuristics are tested and compared in two real-life cases, and our computational results show encouraging improvements with respect to a human planning solution

  13. Nuclear Glycogen Inclusions in Canine Parietal Cells.

    Science.gov (United States)

    Silvestri, S; Lepri, E; Dall'Aglio, C; Marchesi, M C; Vitellozzi, G

    2017-05-01

    Nuclear glycogen inclusions occur infrequently in pathologic conditions but also in normal human and animal tissues. Their function or significance is unclear. To the best of the authors' knowledge, no reports of nuclear glycogen inclusions in canine parietal cells exist. After initial observations of nuclear inclusions/pseudoinclusions during routine histopathology, the authors retrospectively examined samples of gastric mucosa from dogs presenting with gastrointestinal signs for the presence of intranuclear inclusions/pseudoinclusions and determined their composition using histologic and electron-microscopic methods. In 24 of 108 cases (22%), the authors observed various numbers of intranuclear inclusions/pseudoinclusions within scattered parietal cells. Nuclei were characterized by marked karyomegaly and chromatin margination around a central optically empty or slightly eosinophilic area. The intranuclear inclusions/pseudoinclusions stained positive with periodic acid-Schiff (PAS) and were diastase sensitive, consistent with glycogen. Several PAS-positive/diastase-sensitive sections were further examined by transmission electron microscopy, also using periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining to identify polysaccharides. Ultrastructurally, the nuclear inclusions were composed of electron-dense particles that were not membrane bound, without evidence of nuclear membrane invaginations or cytoplasmic organelles in the nuclei, and positive staining with PA-TCH-SP, confirming a glycogen composition. No cytoplasmic glycogen deposits were observed, suggesting that the intranuclear glycogen inclusions were probably synthesized in loco. Nuclear glycogen inclusions were not associated with gastritis or colonization by Helicobacter-like organisms ( P > .05). Our findings suggest that nuclear glycogen inclusions in canine parietal cells could be an incidental finding. Nevertheless, since nuclear glycogen is present in several pathologic

  14. Glycogen Synthase Kinase-3β

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Lenskjold, Toke; Jacoby, Anne Sophie

    2016-01-01

    cells were quantitated using enzyme immunometric assays. The activity of GSK-3β (serine-9-phosphorylated GSK-3β/total GSK-3β) was lower at baseline compared with follow-up. No significant mean change over time was observed in levels of total GSK-3β and serine-9-phosphorylated GSK-3β. Exploratory......Evidence indicates a role for glycogen synthase kinase-3β (GSK-3β) in the pathophysiology of mood disorders and in cognitive disturbances; however, the natural variation in GSK-3β activity over time is unknown. We aimed to investigate GSK-3β activity over time and its possible correlation...... with emotional lability, subjective mood fluctuations and cognitive function in healthy individuals. Thirty-seven healthy subjects were evaluated with neuropsychological tests and blood samples at baseline and 12-week follow-up. Total GSK-3β and serine-9-phosphorylated GSK-3β in peripheral blood mononuclear...

  15. Malin decreases glycogen accumulation by promoting the degradation of protein targeting to glycogen (PTG)

    OpenAIRE

    Worby, Carolyn A.; Gentry, Matthew S.; Dixon, Jack E.

    2007-01-01

    Lafora disease (LD) is an autosomal recessive neurodegenerative disease that results in progressive myoclonus epilepsy and death. LD is caused by mutations in either the E3 ubiquitin ligase malin or the dual-specificity phosphatase laforin. A hallmark of LD is the accumulation of insoluble glycogen in the cytoplasm of cells from most tissues. Glycogen metabolism is regulated by phosphorylation of key metabolic enzymes. One regulator of this phosphorylation is protein targeting to glycogen (PT...

  16. Energy utilization and gluconeogenesis in isolated leech segmental ganglia: Quantitative studies on the control and cellular localization of endogenous glycogen.

    Science.gov (United States)

    Pennington, A J; Pentreath, V W

    1988-01-01

    The isolated segmental ganglia of the horse leech Haemopis sanguisuga were used as a model system to study the utilization and control of glycogen stores within nervous tissue. The glycogen in the ganglia was extracted and assayed fluorimentrically and its cellular localization and turnover studied by autoradiography in conjunction with [(3)H]glucose. We measured the glycogen after various periods of electrical stimulation and after incubation with K(+), Ca(2+), ouabain and glucose. The results for each experimental ganglion were compared to a paired control ganglion and the results analysed by paired t-tests. Electrical stimulation caused sequential changes in glycogen levels: a reduction of up to 67% (5-10 min); followed by an increase of up to 124% (between 15-50 min); followed by a reduction of up to 63% (60-90 min). Values were calculated for glucose utilization (e.g. 0.53 ?mol glucose/gm wet weight/min after 90 min) and estimates derived for glucose consumption per action potential per neuron (e.g. 0.12 fmol at 90 min). Glucose (1.5-10 mM) increased the amount of glycogen (1.5 mM by 30% at 60 min) and attenuated the effects of electrical stimulation. Ouabain (1 mM) blocked the effect of 5 min electrical stimulation. Nine millimolar K(+) increased glycogen by 27% after 10 min and decreased glycogen by 34% after 60 min; 3 mM Ca(2+) had no effect after 10 or 20 min and decreased glycogen by 29% after 60 min. Other concentrations of K(+) and Ca(2+) reduced glycogen after 60 min. Autoradiographic analysis demonstrated that the effects of elevated K(+) were principally within the glial cells. We conclude that (i) the glycogen stores in the glial cells of leech segmental ganglia provide an endogenous energy source which can support sustained neuronal activity, (ii) both electrical stimulation and elevated K(+) can induce gluconeogenesis within the ganglia, (iii) that electrical activation of neurons produces changes in the glycogen in the glial cells which are

  17. Self-Replenishing Vascularized Fouling-Release Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Howell, C; Vu, TL; Lin, JJ; Kolle, S; Juthani, N; Watson, E; Weaver, JC; Alvarenga, J; Aizenberg, J

    2014-08-13

    Inspired by the long-term effectiveness of living antifouling materials, we have developed a method for the self-replenishment of synthetic biofouling-release surfaces. These surfaces are created by either molding or directly embedding 3D vascular systems into polydimethylsiloxane (PDMS) and filling them with a silicone oil to generate a nontoxic oil-infused material. When replenished with silicone oil from an outside source, these materials are capable of self-lubrication and continuous renewal of the interfacial fouling-release layer. Under accelerated lubricant loss conditions, fully infused vascularized samples retained significantly more lubricant than equivalent nonvascularized controls. Tests of lubricant-infused PDMS in static cultures of the infectious bacteria Staphylococcus aureus and Escherichia coli as well as the green microalgae Botryococcus braunii, Chlamydomonas reinhardtii, Dunaliella sauna, and Nannochloropsis oculata showed a significant reduction in biofilm adhesion compared to PDMS and glass controls containing no lubricant. Further experiments on vascularized versus nonvascularized samples that had been subjected to accelerated lubricant evaporation conditions for up to 48 h showed significantly less biofilm adherence on the vascularized surfaces. These results demonstrate the ability of an embedded lubricant-filled vascular network to improve the longevity of fouling-release surfaces.

  18. Rapidly Dissolving Microneedle Patches for Transdermal Iron Replenishment Therapy.

    Science.gov (United States)

    Maurya, Abhijeet; Nanjappa, Shivakumar H; Honnavar, Swati; Salwa, M; Murthy, S Narasimha

    2018-02-17

    The prevalence of iron deficiency anemia (IDA) is predominant in women and children especially in developing countries. The disorder affects cognitive functions and physical activity. Although oral iron supplementation and parenteral therapy remains the preferred choice of treatment, gastric side effects and risk of iron overload decreases adherence to therapy. Transdermal route is an established approach, which circumvents the side effects associated with conventional therapy. In this project, an attempt was made to investigate the use of rapidly dissolving microneedles loaded with ferric pyrophosphate (FPP) as a potential therapeutic approach for management of IDA. Microneedle array patches were made using the micromolding technique and tested in vitro using rat skin to check the duration required for dissolution/disappearance of needles. The ability of FPP-loaded microneedles to replenish iron was investigated in anemic rats. Rats were fed iron-deficient diet for 5 weeks to induce IDA following which microneedle treatment was initiated. Recovery of rats from anemic state was monitored by measuring hematological and biochemical parameters. Results from in vivo study displayed significant improvements in hemoglobin and serum iron levels after 2-week treatment with FPP-loaded microneedles. The study effectively demonstrated the potential of microneedle-mediated iron replenishment for treatment of IDA. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  19. Muscle glycogen storage postexercise: effect of mode of carbohydrate administration.

    Science.gov (United States)

    Reed, M J; Brozinick, J T; Lee, M C; Ivy, J L

    1989-02-01

    The primary purpose of this study was to determine whether gastric emptying limits the rate of muscle glycogen storage during the initial 4 h after exercise when a carbohydrate supplement is provided. A secondary purpose was to determine whether liquid (L) and solid (S) carbohydrate (CHO) feedings result in different rates of muscle glycogen storage after exercise. Eight subjects cycled for 2 h on three separate occasions to deplete their muscle glycogen stores. After each exercise bout they received 3 g CHO/kg body wt in L (50% glucose polymer) or S (rice/banana cake) form or by intravenous infusion (I; 20% sterile glucose). The L and S supplements were divided into two equal doses and administered immediately after and 120 min after exercise, whereas the I supplement was administered continuously during the first 235 min of the 240-min recovery period. Blood samples were drawn from an antecubital vein before exercise, during exercise, and throughout recovery. Muscle biopsies were taken from the vastus lateralis immediately after and 120 and 240 min after exercise. Blood glucose and insulin declined during exercise and increased significantly above preexercise levels during recovery in all treatments. The increase in blood glucose during the I treatment, however, was three times greater than during the L or S treatments. The average insulin response of the L treatment (61.7 +/- 4.9 microU/ml) was significantly greater than that of the S treatment (47.5 +/- 4.2 microU/ml) but not that of the I (55.3 +/- 4.5 microU/ml) treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. High glycogen levels enhance glycogen breakdown in isolated contracting skeletal muscle

    DEFF Research Database (Denmark)

    Richter, Erik; Galbo, H

    1986-01-01

    and after 15 min of intermittent electrical muscle stimulation. Before stimulation, glycogen was higher in rats that swam on the preceding day (supercompensated rats) compared with controls. During muscle contractions, glycogen breakdown in fast-twitch red and white fibers was larger in supercompensated...

  1. Optimal dynamic pricing and replenishment policies for deteriorating items

    Directory of Open Access Journals (Sweden)

    Masoud Rabbani

    2014-08-01

    Full Text Available Marketing strategies and proper inventory replenishment policies are often incorporated by enterprises to stimulate demand and maximize profit. The aim of this paper is to represent an integrated model for dynamic pricing and inventory control of deteriorating items. To reflect the dynamic characteristic of the problem, the selling price is defined as a time-dependent function of the initial selling price and the discount rate. In this regard, the price is exponentially discounted to compensate negative impact of the deterioration. The planning horizon is assumed to be infinite and the deterioration rate is time-dependent. In addition to price, the demand rate is dependent on advertisement as a powerful marketing tool. Several theoretical results and an iterative solution algorithm are developed to provide the optimal solution. Finally, to show validity of the model and illustrate the solution procedure, numerical results are presented.

  2. Exposures to arsenite and methylarsonite produce insulin resistance and impair insulin-dependent glycogen metabolism in hepatocytes.

    Science.gov (United States)

    Zhang, Chongben; Fennel, Emily M J; Douillet, Christelle; Stýblo, Miroslav

    2017-12-01

    Environmental exposure to inorganic arsenic (iAs) has been shown to disturb glucose homeostasis, leading to diabetes. Previous laboratory studies have suggested several mechanisms that may underlie the diabetogenic effects of iAs exposure, including (i) inhibition of insulin signaling (leading to insulin resistance) in glucose metabolizing peripheral tissues, (ii) inhibition of insulin secretion by pancreatic β cells, and (iii) dysregulation of the methylation or expression of genes involved in maintenance of glucose or insulin metabolism and function. Published studies have also shown that acute or chronic iAs exposures may result in depletion of hepatic glycogen stores. However, effects of iAs on pathways and mechanisms that regulate glycogen metabolism in the liver have never been studied. The present study examined glycogen metabolism in primary murine hepatocytes exposed in vitro to arsenite (iAs 3+ ) or its methylated metabolite, methylarsonite (MAs 3+ ). The results show that 4-h exposures to iAs 3+ and MAs 3+ at concentrations as low as 0.5 and 0.2 µM, respectively, decreased glycogen content in insulin-stimulated hepatocytes by inhibiting insulin-dependent activation of glycogen synthase (GS) and by inducing activity of glycogen phosphorylase (GP). Further investigation revealed that both iAs 3+ and MAs 3+ inhibit insulin-dependent phosphorylation of protein kinase B/Akt, one of the mechanisms involved in the regulation of GS and GP by insulin. Thus, inhibition of insulin signaling (i.e., insulin resistance) is likely responsible for the dysregulation of glycogen metabolism in hepatocytes exposed to iAs 3+ and MAs 3+ . This study provides novel information about the mechanisms by which iAs exposure impairs glucose homeostasis, pointing to hepatic metabolism of glycogen as one of the targets.

  3. Relationship between muscle water and glycogen recovery after prolonged exercise in the heat in humans.

    Science.gov (United States)

    Fernández-Elías, Valentín E; Ortega, Juan F; Nelson, Rachael K; Mora-Rodriguez, Ricardo

    2015-09-01

    It is usually stated that glycogen is stored in human muscle bound to water in a proportion of 1:3 g. We investigated this proportion in biopsy samples during recovery from prolonged exercise. On two occasions, nine aerobically trained subjects ([Formula: see text] = 54.4 ± 1.05 mL kg(-1) min(-1); mean ± SD) dehydrated 4.6 ± 0.2 % by cycling 150 min at 65 % [Formula: see text] in a hot-dry environment (33 ± 4 °C). One hour after exercise subjects ingested 250 g of carbohydrates in 400 mL of water (REHLOW) or the same syrup plus water to match fluid losses (i.e., 3170 ± 190 mL; REHFULL). Muscle biopsies were obtained before, 1 and 4 h after exercise. In both trials muscle water decreased from pre-exercise similarly by 13 ± 6 % and muscle glycogen by 44 ± 10 % (P recovery, glycogen levels were similar in both trials (79 ± 15 and 87 ± 18 g kg(-1) dry muscle; P = 0.20) while muscle water content was higher in REHFULL than in REHLOW (3814 ± 222 vs. 3459 ± 324 g kg(-1) dm, respectively; P recovery ratio 1:3) while during REHFULL this ratio was higher (1:17). Our findings agree with the long held notion that each gram of glycogen is stored in human muscle with at least 3 g of water. Higher ratios are possible (e.g., during REHFULL) likely due to water storage not bound to glycogen.

  4. Phosphorylation-dependent translocation of glycogen synthase to a novel structure during glycogen resynthesis

    DEFF Research Database (Denmark)

    Prats, Clara; Cadefau, Joan A; Cussó, Roser

    2005-01-01

    Glycogen metabolism has been the subject of extensive research, but the mechanisms by which it is regulated are still not fully understood. It is well accepted that the rate-limiting enzymes in glycogenesis and glycogenolysis are glycogen synthase (GS) and glycogen phosphorylase (GPh), respectively....... Both enzymes are regulated by reversible phosphorylation and by allosteric effectors. However, evidence in the literature indicates that changes in muscle GS and GPh intracellular distribution may constitute a new regulatory mechanism of glycogen metabolism. Already in the 1960s, it was proposed...... that glycogen was present in dynamic cellular organelles that were termed glycosomas but no such cellular entities have ever been demonstrated. The aim of this study was to characterize muscle GS and GPh intracellular distribution and to identify possible translocation processes of both enzymes. Using in situ...

  5. Relationship between single nucleotide polymorphism of glycogen synthase gene of Pacific oyster Crassostrea gigas and its glycogen content

    Science.gov (United States)

    Liu, Siwei; Li, Qi; Yu, Hong; Kong, Lingfeng

    2017-02-01

    Glycogen is important not only for the energy supplementary of oysters, but also for human consumption. High glycogen content can improve the stress survival of oyster. A key enzyme in glycogenesis is glycogen synthase that is encoded by glycogen synthase gene GYS. In this study, the relationship between single nucleotide polymorphisms (SNPs) in coding regions of Crassostrea gigas GYS (Cg-GYS) and individual glycogen content was investigated with 321 individuals from five full-sib families. Single-strand conformation polymorphism (SSCP) procedure was combined with sequencing to confirm individual SNP genotypes of Cg-GYS. Least-square analysis of variance was performed to assess the relationship of variation in glycogen content of C. gigas with single SNP genotype and SNP haplotype. As a consequence, six SNPs were found in coding regions to be significantly associated with glycogen content ( P glycogen content ( P glycogen content and provided molecular biological information for the selective breeding of good quality traits of C. gigas.

  6. Two replenishment strategies for the lost sales inventory model: a comparison

    NARCIS (Netherlands)

    Donselaar, van K.H.; Kok, de A.G.; Rutten, W.G.M.M.

    1996-01-01

    For the lost sales inventory system we distinguish two different replenishment strategies. The simplest strategy is the classical ‘fixed reorder level’ replenishment rule: every period the inventory position in the system is raised up to a fixed quantity S. For this simple strategy we derive and

  7. Exercise in muscle glycogen storage diseases.

    Science.gov (United States)

    Preisler, Nicolai; Haller, Ronald G; Vissing, John

    2015-05-01

    Glycogen storage diseases (GSD) are inborn errors of glycogen or glucose metabolism. In the GSDs that affect muscle, the consequence of a block in skeletal muscle glycogen breakdown or glucose use, is an impairment of muscular performance and exercise intolerance, owing to 1) an increase in glycogen storage that disrupts contractile function and/or 2) a reduced substrate turnover below the block, which inhibits skeletal muscle ATP production. Immobility is associated with metabolic alterations in muscle leading to an increased dependence on glycogen use and a reduced capacity for fatty acid oxidation. Such changes may be detrimental for persons with GSD from a metabolic perspective. However, exercise may alter skeletal muscle substrate metabolism in ways that are beneficial for patients with GSD, such as improving exercise tolerance and increasing fatty acid oxidation. In addition, a regular exercise program has the potential to improve general health and fitness and improve quality of life, if executed properly. In this review, we describe skeletal muscle substrate use during exercise in GSDs, and how blocks in metabolic pathways affect exercise tolerance in GSDs. We review the studies that have examined the effect of regular exercise training in different types of GSD. Finally, we consider how oral substrate supplementation can improve exercise tolerance and we discuss the precautions that apply to persons with GSD that engage in exercise.

  8. ATP, IMP, and glycogen in cod muscle at onset and during development of rigor mortis depend on the sampling location

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming

    2002-01-01

    Variation in glycogen, ATP, and IMP contents within individual cod muscles were studied in ice stored fish during the progress of rigor mortis. Rigor index was determined before muscle samples for chemical analyzes were taken at 16 different positions on the fish. During development of rigor......, the contents of glycogen and ATP decreased differently in relation to rigor index depending on sampling location. Although fish were considered to be in strong rigor according to the rigor index method, parts of the muscle were not in rigor as high ATP concentrations were found in dorsal and tall muscle....

  9. A novel multi-item joint replenishment problem considering multiple type discounts.

    Directory of Open Access Journals (Sweden)

    Ligang Cui

    Full Text Available In business replenishment, discount offers of multi-item may either provide different discount schedules with a single discount type, or provide schedules with multiple discount types. The paper investigates the joint effects of multiple discount schemes on the decisions of multi-item joint replenishment. In this paper, a joint replenishment problem (JRP model, considering three discount (all-unit discount, incremental discount, total volume discount offers simultaneously, is constructed to determine the basic cycle time and joint replenishment frequencies of multi-item. To solve the proposed problem, a heuristic algorithm is proposed to find the optimal solutions and the corresponding total cost of the JRP model. Numerical experiment is performed to test the algorithm and the computational results of JRPs under different discount combinations show different significance in the replenishment cost reduction.

  10. Partial recovery of erythrocyte glycogen in diabetic rats treated with phenobarbital

    Directory of Open Access Journals (Sweden)

    da-Silva C.A.

    1997-01-01

    Full Text Available Erythrocytes may play a role in glucose homeostasis during the postprandial period. Erythrocytes from diabetic patients are defective in glucose transport and metabolism, functions that may affect glycogen storage. Phenobarbital, a hepatic enzyme inducer, has been used in the treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM, increasing the insulin-mediated glucose disposal. We studied the effects of phenobarbital treatment in vivo on glycemia and erythrocyte glycogen content in control and alloxan-diabetic rats during the postprandial period. In control rats (blood glucose, 73 to 111 mg/dl in femoral and suprahepatic veins the erythrocyte glycogen content was 45.4 ± 1.1 and 39.1 ± 0.8 µg/g Hb (mean ± SEM, N = 4-6 in the femoral artery and vein, respectively, and 37.9 ± 1.1 in the portal vein and 47.5 ± 0.9 in the suprahepatic vein. Diabetic rats (blood glucose, 300-350 mg/dl presented low (P<0.05 erythrocyte glycogen content, i.e., 9.6 ± 0.1 and 7.1 ± 0.7 µg/g Hb in the femoral artery and vein, respectively, and 10.0 ± 0.7 and 10.7 ± 0.5 in the portal and suprahepatic veins, respectively. After 10 days of treatment, phenobarbital (0.5 mg/ml in the drinking water did not change blood glucose or erythrocyte glycogen content in control rats. In diabetic rats, however, it lowered (P<0.05 blood glucose in the femoral artery (from 305 ± 18 to 204 ± 45 mg/dl and femoral vein (from 300 ± 11 to 174 ± 48 mg/dl and suprahepatic vein (from 350 ± 10 to 174 ± 42 mg/dl, but the reduction was not sufficient for complete recovery. Phenobarbital also stimulated the glycogen synthesis, leading to a partial recovery of glycogen stores in erythrocytes. In treated rats, erythrocyte glycogen content increased to 20.7 ± 3.8 µg/g Hb in the femoral artery and 30.9 ± 0.9 µg/g Hb in the suprahepatic vein (P<0.05. These data indicate that phenobarbital activated some of the insulin-stimulated glucose metabolism steps which were

  11. Muscle Glycogen Remodeling and Glycogen Phosphate Metabolism following Exhaustive Exercise of Wild Type and Laforin Knockout Mice*

    Science.gov (United States)

    Irimia, Jose M.; Tagliabracci, Vincent S.; Meyer, Catalina M.; Segvich, Dyann M.; DePaoli-Roach, Anna A.; Roach, Peter J.

    2015-01-01

    Glycogen, the repository of glucose in many cell types, contains small amounts of covalent phosphate, of uncertain function and poorly understood metabolism. Loss-of-function mutations in the laforin gene cause the fatal neurodegenerative disorder, Lafora disease, characterized by increased glycogen phosphorylation and the formation of abnormal deposits of glycogen-like material called Lafora bodies. It is generally accepted that the phosphate is removed by the laforin phosphatase. To study the dynamics of skeletal muscle glycogen phosphorylation in vivo under physiological conditions, mice were subjected to glycogen-depleting exercise and then monitored while they resynthesized glycogen. Depletion of glycogen by exercise was associated with a substantial reduction in total glycogen phosphate and the newly resynthesized glycogen was less branched and less phosphorylated. Branching returned to normal on a time frame of days, whereas phosphorylation remained suppressed over a longer period of time. We observed no change in markers of autophagy. Exercise of 3-month-old laforin knock-out mice caused a similar depletion of glycogen but no loss of glycogen phosphate. Furthermore, remodeling of glycogen to restore the basal branching pattern was delayed in the knock-out animals. From these results, we infer that 1) laforin is responsible for glycogen dephosphorylation during exercise and acts during the cytosolic degradation of glycogen, 2) excess glycogen phosphorylation in the absence of laforin delays the normal remodeling of the branching structure, and 3) the accumulation of glycogen phosphate is a relatively slow process involving multiple cycles of glycogen synthesis-degradation, consistent with the slow onset of the symptoms of Lafora disease. PMID:26216881

  12. Exercise in muscle glycogen storage diseases

    DEFF Research Database (Denmark)

    Preisler, Nicolai Rasmus; Haller, Ronald G; Vissing, John

    2015-01-01

    exercise program has the potential to improve general health and fitness and improve quality of life, if executed properly. In this review, we describe skeletal muscle substrate use during exercise in GSDs, and how blocks in metabolic pathways affect exercise tolerance in GSDs. We review the studies...... that have examined the effect of regular exercise training in different types of GSD. Finally, we consider how oral substrate supplementation can improve exercise tolerance and we discuss the precautions that apply to persons with GSD that engage in exercise.......Glycogen storage diseases (GSD) are inborn errors of glycogen or glucose metabolism. In the GSDs that affect muscle, the consequence of a block in skeletal muscle glycogen breakdown or glucose use, is an impairment of muscular performance and exercise intolerance, owing to 1) an increase...

  13. No effect of glycogen level on glycogen metabolism during high intensity exercise

    DEFF Research Database (Denmark)

    Vandenberghe, Katleen; Hespel, P.; Eynde, Bart Vanden

    1995-01-01

    , either for 1 min 45 s (protocol 1; N = 18) or to exhaustion (protocol 2; N = 14). The exercise tests were preceded by either 5 d on a controlled normal (N) diet, or by 2 d of glycogen-depleting exercise accompanied by the normal diet followed by 3 d on a carbohydrate-rich (CHR) diet. In protocol 1......This study examined the effect of glycogen supercompensation on glycogen breakdown, muscle and blood lactate accumulation, blood-pH, and performance during short-term high-intensity exercise. Young healthy volunteers performed two supramaximal (125% of VO2max) exercise tests on a bicycle ergometer...

  14. Glycogen metabolism in aerobic mixed cultures

    DEFF Research Database (Denmark)

    Dircks, Klaus; Beun, J.J.; van Loosdrecht, M.C.M.

    2001-01-01

    In this study, the metabolism of glycogen storage and consumption in mixed cultures under aerobic conditions is described. The experimental results are used to calibrate a metabolic model, which as sole stoichiometric variables has the efficiency of oxidative phosphorylation (delta) and maintenance...... of glycogen and subsequent growth occur without significant loss of energy, as compared with direct growth on glucose. For kinetic modeling, Monod kinetics is used most commonly in activated sludge models to describe the rate of microbial transformation. Monod kinetics, however, does not provide a good...

  15. Cell swelling and glycogen metabolism in hepatocytes from fasted rats

    NARCIS (Netherlands)

    Gustafson, L. A.; Jumelle-Laclau, M. N.; van Woerkom, G. M.; van Kuilenburg, A. B.; Meijer, A. J.

    1997-01-01

    Cell swelling is known to increase net glycogen production from glucose in hepatocytes from fasted rats by activating glycogen synthase. Since both active glycogen synthase and phosphorylase are present in hepatocytes, suppression of flux through phosphorylase may also contribute to the net increase

  16. Mechanism of activation of liver glycogen synthase by swelling

    NARCIS (Netherlands)

    Meijer, A. J.; Baquet, A.; Gustafson, L.; van Woerkom, G. M.; Hue, L.

    1992-01-01

    The mechanism linking the stimulation of liver glycogen synthesis to swelling induced either by amino acids or hypotonicity was studied in hepatocytes, in gel-filtered liver extracts, and in purified preparations of particulate glycogen to which glycogen-metabolizing enzymes are bound. High

  17. Replenishment of system spares for improved economic performance

    International Nuclear Information System (INIS)

    McVay, J.L.; Gray, G.

    1990-01-01

    The nuclear industry continues to be faced with increasing external pressures that contribute to escalating production costs. In the past, regulatory and political pressures have been the chief sources for the authors concern. Today, however, the economic aspects for power generation may present an equal or an even greater challenge to the industry's stability. For nuclear utilities to survive and prosper, they must become more cost conscious and competitive. This challenge becomes even more important when one considers the growing number of cogeneration facilities, new independent power producers, and neighboring utilities all competing for the customer on a cost basis. This paper addresses opportunities created by the development of recent industry guidelines addressing engineering analysis techniques to be used during replenishment of system spares and components. This activity, while it has not been traditionally thought of as an engineering activity, can contribute significantly to the reduction of operation and maintenance (O and M) costs for plant systems and will help nuclear utilities to aggressively battle the rising issue of cost control

  18. Parity Bit Replenishment for JPEG 2000-Based Video Streaming

    Directory of Open Access Journals (Sweden)

    François-Olivier Devaux

    2009-01-01

    Full Text Available This paper envisions coding with side information to design a highly scalable video codec. To achieve fine-grained scalability in terms of resolution, quality, and spatial access as well as temporal access to individual frames, the JPEG 2000 coding algorithm has been considered as the reference algorithm to encode INTRA information, and coding with side information has been envisioned to refresh the blocks that change between two consecutive images of a video sequence. One advantage of coding with side information compared to conventional closed-loop hybrid video coding schemes lies in the fact that parity bits are designed to correct stochastic errors and not to encode deterministic prediction errors. This enables the codec to support some desynchronization between the encoder and the decoder, which is particularly helpful to adapt on the fly pre-encoded content to fluctuating network resources and/or user preferences in terms of regions of interest. Regarding the coding scheme itself, to preserve both quality scalability and compliance to the JPEG 2000 wavelet representation, a particular attention has been devoted to the definition of a practical coding framework able to exploit not only the temporal but also spatial correlation among wavelet subbands coefficients, while computing the parity bits on subsets of wavelet bit-planes. Simulations have shown that compared to pure INTRA-based conditional replenishment solutions, the addition of the parity bits option decreases the transmission cost in terms of bandwidth, while preserving access flexibility.

  19. The Economics of Groundwater Replenishment for Reliable Urban Water Supply

    Directory of Open Access Journals (Sweden)

    Lei Gao

    2014-06-01

    Full Text Available This paper explores the potential economic benefits of water banking in aquifers to meet drought and emergency supplies for cities where the population is growing and changing climate has reduced the availability of water. A simplified case study based on the city of Perth, Australia was used to estimate the savings that could be achieved by water banking. Scenarios for investment in seawater desalination plants and groundwater replenishment were considered over a 20 year period of growing demand, using a Monte Carlo analysis that embedded the Markov model. An optimisation algorithm identified the minimum cost solutions that met specified criteria for supply reliability. The impact of depreciation of recharge credits was explored. The results revealed savings of more than A$1B (~US$1B or 37% to 33% of supply augmentation costs by including water banking in aquifers for 95% and 99.5% reliability of supply respectively. When the hypothetically assumed recharge credit depreciation rate was increased from 1% p.a. to 10% p.a. savings were still 33% to 31% for the same reliabilities. These preliminary results show that water banking in aquifers has potential to offer a highly attractive solution for efficiently increasing the security of urban water supplies where aquifers are suitable.

  20. Glycogen Shunt Activity and Glycolytic Supercompensation in Astrocytes May Be Distinctly Mediated via the Muscle Form of Glycogen Phosphorylase

    DEFF Research Database (Denmark)

    Jakobsen, Emil; Bak, Lasse K; Walls, Anne B

    2017-01-01

    Glycogen is the main storage form of glucose in the brain. In contrast with previous beliefs, brain glycogen has recently been shown to play important roles in several brain functions. A fraction of metabolized glucose molecules are being shunted through glycogen before reentering the glycolytic ...

  1. Axonal and dendritic localization of mRNAs for glycogen-metabolizing enzymes in cultured rodent neurons.

    Science.gov (United States)

    Pfeiffer-Guglielmi, Brigitte; Dombert, Benjamin; Jablonka, Sibylle; Hausherr, Vanessa; van Thriel, Christoph; Schöbel, Nicole; Jansen, Ralf-Peter

    2014-06-04

    Localization of mRNAs encoding cytoskeletal or signaling proteins to neuronal processes is known to contribute to axon growth, synaptic differentiation and plasticity. In addition, a still increasing spectrum of mRNAs has been demonstrated to be localized under different conditions and developing stages thus reflecting a highly regulated mechanism and a role of mRNA localization in a broad range of cellular processes. Applying fluorescence in-situ-hybridization with specific riboprobes on cultured neurons and nervous tissue sections, we investigated whether the mRNAs for two metabolic enzymes, namely glycogen synthase (GS) and glycogen phosphorylase (GP), the key enzymes of glycogen metabolism, may also be targeted to neuronal processes. If it were so, this might contribute to clarify the so far enigmatic role of neuronal glycogen. We found that the mRNAs for both enzymes are localized to axonal and dendritic processes in cultured lumbar spinal motoneurons, but not in cultured trigeminal neurons. In cultured cortical neurons which do not store glycogen but nevertheless express glycogen synthase, the GS mRNA is also subject to axonal and dendritic localization. In spinal motoneurons and trigeminal neurons in situ, however, the mRNAs could only be demonstrated in the neuronal somata but not in the nerves. We could demonstrate that the mRNAs for major enzymes of neural energy metabolism can be localized to neuronal processes. The heterogeneous pattern of mRNA localization in different culture types and developmental stages stresses that mRNA localization is a versatile mechanism for the fine-tuning of cellular events. Our findings suggest that mRNA localization for enzymes of glycogen metabolism could allow adaptation to spatial and temporal energy demands in neuronal events like growth, repair and synaptic transmission.

  2. Insights into Brain Glycogen Metabolism: THE STRUCTURE OF HUMAN BRAIN GLYCOGEN PHOSPHORYLASE.

    Science.gov (United States)

    Mathieu, Cécile; Li de la Sierra-Gallay, Ines; Duval, Romain; Xu, Ximing; Cocaign, Angélique; Léger, Thibaut; Woffendin, Gary; Camadro, Jean-Michel; Etchebest, Catherine; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2016-08-26

    Brain glycogen metabolism plays a critical role in major brain functions such as learning or memory consolidation. However, alteration of glycogen metabolism and glycogen accumulation in the brain contributes to neurodegeneration as observed in Lafora disease. Glycogen phosphorylase (GP), a key enzyme in glycogen metabolism, catalyzes the rate-limiting step of glycogen mobilization. Moreover, the allosteric regulation of the three GP isozymes (muscle, liver, and brain) by metabolites and phosphorylation, in response to hormonal signaling, fine-tunes glycogenolysis to fulfill energetic and metabolic requirements. Whereas the structures of muscle and liver GPs have been known for decades, the structure of brain GP (bGP) has remained elusive despite its critical role in brain glycogen metabolism. Here, we report the crystal structure of human bGP in complex with PEG 400 (2.5 Å) and in complex with its allosteric activator AMP (3.4 Å). These structures demonstrate that bGP has a closer structural relationship with muscle GP, which is also activated by AMP, contrary to liver GP, which is not. Importantly, despite the structural similarities between human bGP and the two other mammalian isozymes, the bGP structures reveal molecular features unique to the brain isozyme that provide a deeper understanding of the differences in the activation properties of these allosteric enzymes by the allosteric effector AMP. Overall, our study further supports that the distinct structural and regulatory properties of GP isozymes contribute to the different functions of muscle, liver, and brain glycogen. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Determination of the glycogen content in cyanobacteria

    DEFF Research Database (Denmark)

    Porcellinis, Alice De; Frigaard, Niels-Ulrik; Sakuragi, Yumiko

    2017-01-01

    of glycogen to generate glucose monomers, which are detected by a glucose oxidase-peroxidase (GOD-POD) enzyme coupled assay. The method has been applied to Synechocystis sp. PCC 6803 and Synechococcus sp. PCC 7002, two model cyanobacterial species that are widely used in metabolic engineering. Moreover...

  4. Pregnancies in glycogen storage disease type Ia

    NARCIS (Netherlands)

    Martens, Danielle H. J.; Rake, Jan Peter; Schwarz, Martin; Ullrich, Kurt; Weinstein, David A.; Merkel, Martin; Sauer, Pieter J. J.; Smit, G. Peter A.

    OBJECTIVE: Reports on pregnancies in women with glycogen storage disease type Ia (GSD-Ia) are scarce. Because of improved life expectancy, pregnancy is becoming an important issue. We describe 15 pregnancies by focusing on dietary treatment, biochemical parameters, and GSD-Ia complications. STUDY

  5. Molecular Structure of Human-Liver Glycogen.

    Directory of Open Access Journals (Sweden)

    Bin Deng

    Full Text Available Glycogen is a highly branched glucose polymer which is involved in maintaining blood-sugar homeostasis. Liver glycogen contains large composite α particles made up of linked β particles. Previous studies have shown that the binding which links β particles into α particles is impaired in diabetic mice. The present study reports the first molecular structural characterization of human-liver glycogen from non-diabetic patients, using transmission electron microscopy for morphology and size-exclusion chromatography for the molecular size distribution; the latter is also studied as a function of time during acid hydrolysis in vitro, which is sensitive to certain structural features, particularly glycosidic vs. proteinaceous linkages. The results are compared with those seen in mice and pigs. The molecular structural change during acid hydrolysis is similar in each case, and indicates that the linkage of β into α particles is not glycosidic. This result, and the similar morphology in each case, together imply that human liver glycogen has similar molecular structure to those of mice and pigs. This knowledge will be useful for future diabetes drug targets.

  6. Why does the brain (not) have glycogen?

    Science.gov (United States)

    DiNuzzo, Mauro; Maraviglia, Bruno; Giove, Federico

    2011-05-01

    In the present paper we formulate the hypothesis that brain glycogen is a critical determinant in the modulation of carbohydrate supply at the cellular level. Specifically, we propose that mobilization of astrocytic glycogen after an increase in AMP levels during enhanced neuronal activity controls the concentration of glucose phosphates in astrocytes. This would result in modulation of glucose phosphorylation by hexokinase and upstream cell glucose uptake. This mechanism would favor glucose channeling to activated neurons, supplementing the already rich neuron-astrocyte metabolic and functional partnership with important implications for the energy compounds used to sustain neuronal activity. The hypothesis is based on recent modeling evidence suggesting that rapid glycogen breakdown can profoundly alter the short-term kinetics of glucose delivery to neurons and astrocytes. It is also based on review of the literature relevant to glycogen metabolism during physiological brain activity, with an emphasis on the metabolic pathways identifying both the origin and the fate of this glucose reserve. Copyright © 2011 WILEY Periodicals, Inc.

  7. An Integrated Inventory-Transportation System with Periodic Pick-Ups and Leveled Replenishment

    Directory of Open Access Journals (Sweden)

    Thomas Volling

    2013-11-01

    Full Text Available In this paper we develop a combined inventory-transportation system. The general idea is to integrate a simple replenishment policy with a routing component to derive operationally consistent standard routes as a basis for milk run design. The most interesting feature of the approach is that we combine stochastic vehicle routing with a replenishment policy which makes use of inventory to level the variability propagated into transportation operations. To evaluate the approach, we compare its performance with stochastic vehicle routing as well as sequential vehicle routing and replenishment planning. With respect to these approaches, substantial gains are achieved.

  8. Hepatic glycogen levels in female rats submitted to aquatic therapy after muscle disuse

    Directory of Open Access Journals (Sweden)

    Jefferson Pacheco Amaral Fortes

    2017-12-01

    Full Text Available The aim of the present study was to analyse the changes in liver glycogen content in rats subjected to aquatic therapy post-disuse of the paw. 32 wistar adult female rats were equally divided: Control (C, kept in the cage for two weeks without interventions; Disuse (D had the right paw immobilized with hip extension, knee and plantar flexion for two weeks; Aquatic Therapy (AT underwent aquatic therapy with increments of 3 minutes daily for two weeks, totalizing 36 minutes of training; Disused Aquatic Therapy (DTA was first subjected to immobilization for two weeks and 24 hours after withdrawal of immobilization aquatic therapy was started for two more weeks, in same protocols of D and AT groups. At the end of the experiment, the animals were sacrificed, and tissues were dissected, weighed and stored. The liver tissues were referred analysis of glycogen content. It was observed that the blood glucose levels of the AT group (104 mg/dL were different from the C group (86 mg/dL; p = 0.0213. Regarding hepatic glycogen, the D (2.35mg±0.07 and AT (2.73mg±0.07 groups had hepatic glycogen reduction by 22% and 15%, relative to C (2.51mg±0.03; p <0.0001. The DTA group presented no differences when compared to the control, suggesting the normalization of the finding. Muscle disuse by two weeks promoted changes in glycogen levels, however, two weeks after disuse condition, the aquatic therapy were able to correct the energetic reserve in liver.

  9. Can glycogen be measured by in vivo neutron activation analysis?

    International Nuclear Information System (INIS)

    Sutcliffe, J.F.; Smith, A.H.; King, R.F.G.H.; Smith, M.A.

    1992-01-01

    The object of this note is to examine the feasibility of measuring liver glycogen using in vivo neutron activation analysis. The authors present equations which allow the mass of glycogen to be expressed in terms of the masses of oxygen, hydrogen, carbon and nitrogen. Using the most precise, published measurements of these elements, the standard deviation in the estimate of liver glycogen was 34 g. The magnitude of this error precluded observing changes in liver glycogen which are normally in the range 16 g to 72 g. However, this technique might be useful in detecting transient high concentrations of liver glycogen.(UK)

  10. Glycogen with short average chain length enhances bacterial durability

    Science.gov (United States)

    Wang, Liang; Wise, Michael J.

    2011-09-01

    Glycogen is conventionally viewed as an energy reserve that can be rapidly mobilized for ATP production in higher organisms. However, several studies have noted that glycogen with short average chain length in some bacteria is degraded very slowly. In addition, slow utilization of glycogen is correlated with bacterial viability, that is, the slower the glycogen breakdown rate, the longer the bacterial survival time in the external environment under starvation conditions. We call that a durable energy storage mechanism (DESM). In this review, evidence from microbiology, biochemistry, and molecular biology will be assembled to support the hypothesis of glycogen as a durable energy storage compound. One method for testing the DESM hypothesis is proposed.

  11. Glycogen and Glucose Metabolism Are Essential for Early Embryonic Development of the Red Flour Beetle Tribolium castaneum

    Science.gov (United States)

    Fraga, Amanda; Ribeiro, Lupis; Lobato, Mariana; Santos, Vitória; Silva, José Roberto; Gomes, Helga; da Cunha Moraes, Jorge Luiz; de Souza Menezes, Jackson

    2013-01-01

    Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis) and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3) and hexokinase (HexA) genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi) of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen. PMID:23750237

  12. Radiometric assays for glycerol, glucose, and glycogen

    International Nuclear Information System (INIS)

    Bradley, D.C.; Kaslow, H.R.

    1989-01-01

    We have developed radiometric assays for small quantities of glycerol, glucose and glycogen, based on a technique described by Thorner and Paulus for the measurement of glycerokinase activity. In the glycerol assay, glycerol is phosphorylated with [32P]ATP and glycerokinase, residual [32P]ATP is hydrolyzed by heating in acid, and free [32P]phosphate is removed by precipitation with ammonium molybdate and triethylamine. Standard dose-response curves were linear from 50 to 3000 pmol glycerol with less than 3% SD in triplicate measurements. Of the substances tested for interference, only dihydroxyacetone gave a slight false positive signal at high concentration. When used to measure glycerol concentrations in serum and in media from incubated adipose tissue, the radiometric glycerol assay correlated well with a commonly used spectrophotometric assay. The radiometric glucose assay is similar to the glycerol assay, except that glucokinase is used instead of glycerokinase. Dose response was linear from 5 to 3000 pmol glucose with less than 3% SD in triplicate measurements. Glucosamine and N-acetylglucosamine gave false positive signals when equimolar to glucose. When glucose concentrations in serum were measured, the radiometric glucose assay agreed well with hexokinase/glucose-6-phosphate dehydrogenase (H/GDH)-based and glucose oxidase/H2O2-based glucose assays. The radiometric method for glycogen measurement incorporates previously described isolation and digestion techniques, followed by the radiometric assay of free glucose. When used to measure glycogen in mouse epididymal fat pads, the radiometric glycogen assay correlated well with the H/GDH-based glycogen assay. All three radiometric assays offer several practical advantages over spectral assays

  13. Patterns of glycogen turnover in liver characterized by computer modeling

    International Nuclear Information System (INIS)

    Youn, J.H.; Bergman, R.N.

    1987-01-01

    The authors used a computer model of liver glycogen turnover to reexamine the data of Devos and Hers, who reported the time course of accumulation in and loss from glycogen of label originating in [1- 14 C]galactose injected at different times after the start of refeeding of 40-h fasted mice or rats. In the present study computer representation of individual glycogen molecules was utilized to account for growth and degradation of glycogen according to specific hypothetical patterns. Using this model they could predict the accumulation and localization within glycogen of labeled glucose residues and compare the predictions with the previously published data. They considered three specific hypotheses of glycogen accumulation during refeeding: (1) simultaneous, (2) sequential, and (3) accelerating growth. Hypothetical patterns of glycogen degradation were (1) ordered and (2) random degradation. The pattern of glycogen synthesis consistent with experimental data was a steadily increasing number of growing glycogen molecules, whereas during degradation glycogen molecules are exposed to degrading enzymes randomly, rather than in a specific reverse order of synthesis. These patterns predict the existence of a specific mechanism for the steadily increasing seeding of new glycogen molecules during synthesis

  14. Schwann Cell Glycogen Selectively Supports Myelinated Axon Function

    Science.gov (United States)

    Brown, Angus M; Evans, Richard D; Black, Joel; Ransom, Bruce R

    2012-01-01

    Objectives Interruption of energy supply to peripheral axons is a cause of axon loss. We determined if glycogen was present in mammalian peripheral nerve, and if it supported axon conduction during aglycemia. Methods We used biochemical assay and electron microscopy to determine the presence of glycogen, and electrophysiology to monitor axon function. Results Glycogen was present in sciatic nerve, its concentration varying directly with ambient [glucose]. Electron microscopy detected glycogen granules primarily in myelinating Schwann cell cytoplasm and these diminished after exposure to aglycemia. During aglycemia, conduction failure in large myelinated axons (A fibers) mirrored the time-course of glycogen loss. Latency to CAP failure was directly related to nerve glycogen content at aglycemia onset. Glycogen did not benefit the function of slow-conducting, small diameter unmyelinated axons (C fibers) during aglycemia. Blocking glycogen breakdown pharmacologically accelerated CAP failure during aglycemia in A fibers, but not in C fibers. Lactate was as effective as glucose in supporting sciatic nerve function, and was continuously released into the extracellular space in the presence of glucose and fell rapidly during aglycemia. Interpretation Our findings indicated that glycogen is present in peripheral nerve, primarily in myelinating Schwann cells, and exclusively supports large diameter, myelinated axon conduction during aglycemia. Available evidence suggests that peripheral nerve glycogen breaks down during aglycemia and is passed, probably as lactate, to myelinated axons to support function. Unmyelinated axons are not protected by glycogen and are more vulnerable to dysfunction during periods of hypoglycemia. PMID:23034913

  15. TO STORES USERS

    CERN Multimedia

    SPL Division

    2001-01-01

    Stores users are informed that the Stores (Central, Emergency window, Raw materials, Chemical products and Prévessin Self service stores) will be closed on Friday, 7 December owing to migration of the Stores computers to Windows 2000. Thank you for your understanding.

  16. Lack of Glycogenin Causes Glycogen Accumulation and Muscle Function Impairment.

    Science.gov (United States)

    Testoni, Giorgia; Duran, Jordi; García-Rocha, Mar; Vilaplana, Francisco; Serrano, Antonio L; Sebastián, David; López-Soldado, Iliana; Sullivan, Mitchell A; Slebe, Felipe; Vilaseca, Marta; Muñoz-Cánoves, Pura; Guinovart, Joan J

    2017-07-05

    Glycogenin is considered essential for glycogen synthesis, as it acts as a primer for the initiation of the polysaccharide chain. Against expectations, glycogenin-deficient mice (Gyg KO) accumulate high amounts of glycogen in striated muscle. Furthermore, this glycogen contains no covalently bound protein, thereby demonstrating that a protein primer is not strictly necessary for the synthesis of the polysaccharide in vivo. Strikingly, in spite of the higher glycogen content, Gyg KO mice showed lower resting energy expenditure and less resistance than control animals when subjected to endurance exercise. These observations can be attributed to a switch of oxidative myofibers toward glycolytic metabolism. Mice overexpressing glycogen synthase in the muscle showed similar alterations, thus indicating that this switch is caused by the excess of glycogen. These results may explain the muscular defects of GSD XV patients, who lack glycogenin-1 and show high glycogen accumulation in muscle. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Introduction to the Thematic Minireview Series: Brain glycogen metabolism.

    Science.gov (United States)

    Carlson, Gerald M; Dienel, Gerald A; Colbran, Roger J

    2018-05-11

    The synthesis of glycogen allows for efficient intracellular storage of glucose molecules in a soluble form that can be rapidly released to enter glycolysis in response to energy demand. Intensive studies of glucose and glycogen metabolism, predominantly in skeletal muscle and liver, have produced innumerable insights into the mechanisms of hormone action, resulting in the award of several Nobel Prizes over the last one hundred years. Glycogen is actually present in all cells and tissues, albeit at much lower levels than found in muscle or liver. However, metabolic and physiological roles of glycogen in other tissues are poorly understood. This series of Minireviews summarizes what is known about the enzymes involved in brain glycogen metabolism and studies that have linked glycogen metabolism to multiple brain functions involving metabolic communication between astrocytes and neurons. Recent studies unexpectedly linking some forms of epilepsy to mutations in two poorly understood proteins involved in glycogen metabolism are also reviewed. © 2018 Carlson et al.

  18. Characterization of the highly branched glycogen from the thermoacidophilic red microalga Galdieria sulphuraria and comparison with other glycogens.

    Science.gov (United States)

    Martinez-Garcia, Marta; Stuart, Marc C A; van der Maarel, Marc J E C

    2016-08-01

    The thermoacidophilic red microalga Galdieria sulphuraria synthesizes glycogen when growing under heterotrophic conditions. Structural characterization revealed that G. sulphuraria glycogen is the most highly branched glycogen described to date, with 18% of α-(1→6) linkages. Moreover, it differs from other glycogens because it is composed of short chains only and has a substantially smaller molecular weight and particle size. The physiological role of this highly branched glycogen in G. sulphuraria is discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Processivity and Subcellular Localization of Glycogen Synthase Depend on a Non-catalytic High Affinity Glycogen-binding Site*

    OpenAIRE

    Díaz, Adelaida; Martínez-Pons, Carlos; Fita, Ignacio; Ferrer, Juan C.; Guinovart, Joan J.

    2011-01-01

    Glycogen synthase, a central enzyme in glucose metabolism, catalyzes the successive addition of α-1,4-linked glucose residues to the non-reducing end of a growing glycogen molecule. A non-catalytic glycogen-binding site, identified by x-ray crystallography on the surface of the glycogen synthase from the archaeon Pyrococcus abyssi, has been found to be functionally conserved in the eukaryotic enzymes. The disruption of this binding site in both the archaeal and the human muscle glycogen synth...

  20. Ordered synthesis and mobilization of glycogen in the perfused heart

    International Nuclear Information System (INIS)

    Brainard, J.R.; Hutson, J.Y.; Hoekenga, D.E.; Lenhoff, R.

    1989-01-01

    The molecular order of synthesis and mobilization of glycogen in the perfused heart was studied by 13 C NMR. By varying the glucose isotopomer ([1- 13 C]glucose or [2- 13 C]glucose) supplied to the heart, glycogen synthesized at different times during the perfusion was labeled at different carbon sites. Subsequently, the in situ mobilization of glycogen during ischemia was observed by detection of labeled lactate derived from glycolysis of the glucosyl monomers. When [1- 13 C]glucose was given initially in the perfusion and [2- 13 C]glucose was given second, [2- 13 C]lactate was detected first during ischemia and [3- 13 C]lactate second. This result, and the equivalent result when the glucose labels were given in the reverse order, demonstrates that glycogen synthesis and mobilization are ordered in the heart, where glycogen is found morphologically only as β particles. Previous studies of glycogen synthesis and mobilization in liver and adipocytes have suggested that the organization of β particles into α particles was partially responsible for ordered synthesis and mobilization. The observations reported here for cardiac glycogen suggest that another mechanism is responsible. In addition to examine the ordered synthesis and mobilization of cardiac glycogen, the authors have selectively monitored the NMR properties of 13 C-labeled glycogen synthesized early in the perfusion during further glycogen synthesis from a second, differently labeled substrate. During synthesis from the second labeled glucose monomer, the glycogen resonance from the first label decreased in integrated intensity and increased in line width. These results suggest either that there is significant isotopic exchange of glucosyl monomers in glycogen during net synthesis or that glucosyl residues incorporated into glycogen undergo motional restrictions as further glycogen synthesis occurs

  1. Glycogen synthesis is induced in hypoxia by the hypoxia-inducible factor and promotes cancer cell survival

    Directory of Open Access Journals (Sweden)

    Joffrey ePelletier

    2012-02-01

    Full Text Available The hypoxia-inducible factor 1 (HIF-1, in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1, were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these hypoxia-preconditioned cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO2 acts as an alarm that prepares the cells to face subsequent nutrient depletion and to survive.

  2. Glycogen Synthesis is Induced in Hypoxia by the Hypoxia-Inducible Factor and Promotes Cancer Cell Survival

    Energy Technology Data Exchange (ETDEWEB)

    Pelletier, Joffrey; Bellot, Grégory [Institute of Developmental Biology and Cancer Research, CNRS-UMR 6543, Centre Antoine Lacassagne, University of Nice-Sophia Antipolis, Nice (France); Gounon, Pierre; Lacas-Gervais, Sandra [Centre Commun de Microscopie Appliquée, University of Nice-Sophia Antipolis, Nice (France); Pouysségur, Jacques; Mazure, Nathalie M., E-mail: mazure@unice.fr [Institute of Developmental Biology and Cancer Research, CNRS-UMR 6543, Centre Antoine Lacassagne, University of Nice-Sophia Antipolis, Nice (France)

    2012-02-28

    The hypoxia-inducible factor 1 (HIF-1), in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1), were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these “hypoxia-preconditioned” cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO{sub 2} acts as an “alarm” that prepares the cells to face subsequent nutrient depletion and to survive.

  3. Glycogen Synthesis is Induced in Hypoxia by the Hypoxia-Inducible Factor and Promotes Cancer Cell Survival

    International Nuclear Information System (INIS)

    Pelletier, Joffrey; Bellot, Grégory; Gounon, Pierre; Lacas-Gervais, Sandra; Pouysségur, Jacques; Mazure, Nathalie M.

    2012-01-01

    The hypoxia-inducible factor 1 (HIF-1), in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1), were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these “hypoxia-preconditioned” cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO 2 acts as an “alarm” that prepares the cells to face subsequent nutrient depletion and to survive.

  4. Contingency factors in the configuration of information systems for continuous replenishment: a case study in Indonesia

    NARCIS (Netherlands)

    Nasution, R.A.; Nasution, R.A.; Stegwee, R.A.; de Bruijn, E.J.; Sadler, I.; Power, D.; Dapiran, G.P.

    2002-01-01

    Contingency theory provides a theoretical framework for analysing the implementation differences in the configuration of Information Systems for Continuous Replenishment in the retail sector. The configuration can be broken down into three arrangements: data processing and sharing arrangement,

  5. Epinephrine-stimulated glycogen breakdown activates glycogen synthase and increases insulin-stimulated glucose uptake in epitrochlearis muscles

    DEFF Research Database (Denmark)

    Kolnes, Anders J; Birk, Jesper Bratz; Eilertsen, Einar

    2015-01-01

    Adrenaline increases glycogen synthase (GS) phosphorylation and decreases GS activity but also stimulates glycogen breakdown and low glycogen content normally activates GS. To test the hypothesis that glycogen content directly regulates GS phosphorylation, glycogen breakdown was stimulated...... in condition with decreased GS activation. Saline or adrenaline (0.02mg/100g rat) was injected subcutaneously in Wistar rats (~130 g) with low (24 h fasted), normal (normal diet) and high glycogen content (fasted-refed) and epitrochlearis muscles were removed after 3 h and incubated ex vivo eliminating...... adrenaline action. Adrenaline injection reduced glycogen content in epitrochlearis muscles with high (120.7±17.8 vs 204.6±14.5 mmol•kg(-1); pglycogen (89.5±7.6 vs 152.6±8.1 mmol•kg(-1); pglycogen (90.0±5.0 vs 102.8±7.8 mmol•kg(-1); p=0...

  6. Myopic control of stochastic inventories with intermittent updates: continuous versus periodic replenishment

    OpenAIRE

    M Shnaiderman

    2012-01-01

    A manufacturer who is responsible for supplying a retailer with a single product is considered. The retailer sells the product in response to stochastic demand and provides the manufacturer with periodic updates about his inventories. Replenishing the retailer's inventory under two myopic base-stock policies is addressed. These policies, referred to as vendor managed inventory, represent a relatively new approach to allocating responsibility in the replenishment process. Specifically, the man...

  7. On the role of trust types and levels on inventory replenishment decision

    OpenAIRE

    Darvish, M.; Kaboli, A.; Cheikhrouhou, N.; Glardon, R.

    2014-01-01

    Using a participatory simulation platform, this paper investigates the inventory replenishment decisions made under different trust categories. Depending on the type of trust (trust in supplier versus trust in customer) and level of trust (high versus low), each decision is categorized and analyzed. We investigate how the inventory manager`s ordering behavior varies regarding their type and level of trust. This study provides evidence for the role of trust in inventory replenishment decision....

  8. Insight into the risk of replenishing urban landscape ponds with reclaimed wastewater.

    Science.gov (United States)

    Chen, Rong; Ao, Dong; Ji, Jiayuan; Wang, Xiaochang C; Li, Yu-You; Huang, Yue; Xue, Tao; Guo, Hongbing; Wang, Nan; Zhang, Lu

    2017-02-15

    Increasing use of reclaimed wastewater (RW) for replenishing urban landscape ponds has aroused public concern about the water quality. Three ponds replenished with RW in three cities in China were chosen to investigate 22 indexes of water quality in five categories. This was achieved by comparing three pairs of ponds in the three different cities, where one pond in each pair was replenished with RW and the other with surface water (SW). The nutrients condition, heavy metal concentration and ecotoxicity did not differ significantly between RW- and SW-replenished ponds. By contrast, significant differences were observed in algal growth and pathogen risk. RW ponds presented a Cyanophyta-Chlorophyta-Bacillariophyta type with high algal diversity while SW ponds presented a Cyanophyta type with low diversity. Regrowth of bacterial pathogens and especially survival of viral pathogens in RW, was the main driver behind the higher risk for RW ponds compared with SW ones. The duration of RW replenishment was proved to have a marked impact on the algal growth and pathogen risk. With continued RW replenishment, non-dominant algal species subjected to decrease while dominant species were enhanced resulting in the biomass increasing but diversity declining, and the risk posed by viral pathogens might become greater. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Functional significance of brain glycogen in sustaining glutamatergic neurotransmission.

    Science.gov (United States)

    Sickmann, Helle M; Walls, Anne B; Schousboe, Arne; Bouman, Stephan D; Waagepetersen, Helle S

    2009-05-01

    The involvement of brain glycogen in sustaining neuronal activity has previously been demonstrated. However, to what extent energy derived from glycogen is consumed by astrocytes themselves or is transferred to the neurons in the form of lactate for oxidative metabolism to proceed is at present unclear. The significance of glycogen in fueling glutamate uptake into astrocytes was specifically addressed in cultured astrocytes. Moreover, the objective was to elucidate whether glycogen derived energy is important for maintaining glutamatergic neurotransmission, induced by repetitive exposure to NMDA in co-cultures of cerebellar neurons and astrocytes. In the astrocytes it was shown that uptake of the glutamate analogue D-[3H]aspartate was impaired when glycogen degradation was inhibited irrespective of the presence of glucose, signifying that energy derived from glycogen degradation is important for the astrocytic compartment. By inhibiting glycogen degradation in co-cultures it was evident that glycogen provides energy to sustain glutamatergic neurotransmission, i.e. release and uptake of glutamate. The relocation of glycogen derived lactate to the neuronal compartment was investigated by employing d-lactate, a competitive substrate for the monocarboxylate transporters. Neurotransmitter release was affected by the presence of d-lactate indicating that glycogen derived energy is important not only in the astrocytic but also in the neuronal compartment.

  10. Role of Maltose Enzymes in Glycogen Synthesis by Escherichia coli▿

    Science.gov (United States)

    Park, Jong-Tae; Shim, Jae-Hoon; Tran, Phuong Lan; Hong, In-Hee; Yong, Hwan-Ung; Oktavina, Ershita Fitria; Nguyen, Hai Dang; Kim, Jung-Wan; Lee, Tae Soo; Park, Sung-Hoon; Boos, Winfried; Park, Kwan-Hwa

    2011-01-01

    Mutants with deletion mutations in the glg and mal gene clusters of Escherichia coli MC4100 were used to gain insight into glycogen and maltodextrin metabolism. Glycogen content, molecular mass, and branch chain distribution were analyzed in the wild type and in ΔmalP (encoding maltodextrin phosphorylase), ΔmalQ (encoding amylomaltase), ΔglgA (encoding glycogen synthase), and ΔglgA ΔmalP derivatives. The wild type showed increasing amounts of glycogen when grown on glucose, maltose, or maltodextrin. When strains were grown on maltose, the glycogen content was 20 times higher in the ΔmalP strain (0.97 mg/mg protein) than in the wild type (0.05 mg/mg protein). When strains were grown on glucose, the ΔmalP strain and the wild type had similar glycogen contents (0.04 mg/mg and 0.03 mg/mg protein, respectively). The ΔmalQ mutant did not grow on maltose but showed wild-type amounts of glycogen when grown on glucose, demonstrating the exclusive function of GlgA for glycogen synthesis in the absence of maltose metabolism. No glycogen was found in the ΔglgA and ΔglgA ΔmalP strains grown on glucose, but substantial amounts (0.18 and 1.0 mg/mg protein, respectively) were found when they were grown on maltodextrin. This demonstrates that the action of MalQ on maltose or maltodextrin can lead to the formation of glycogen and that MalP controls (inhibits) this pathway. In vitro, MalQ in the presence of GlgB (a branching enzyme) was able to form glycogen from maltose or linear maltodextrins. We propose a model of maltodextrin utilization for the formation of glycogen in the absence of glycogen synthase. PMID:21421758

  11. Glycogen Metabolic Genes Are Involved in Trehalose-6-Phosphate Synthase-Mediated Regulation of Pathogenicity by the Rice Blast Fungus Magnaporthe oryzae

    Science.gov (United States)

    Wilson, Richard A.; Wang, Zheng-Yi; Kershaw, Michael J.; Talbot, Nicholas J.

    2013-01-01

    The filamentous fungus Magnaporthe oryzae is the causal agent of rice blast disease. Here we show that glycogen metabolic genes play an important role in plant infection by M. oryzae. Targeted deletion of AGL1 and GPH1, which encode amyloglucosidase and glycogen phosphorylase, respectively, prevented mobilisation of glycogen stores during appressorium development and caused a significant reduction in the ability of M. oryzae to cause rice blast disease. By contrast, targeted mutation of GSN1, which encodes glycogen synthase, significantly reduced the synthesis of intracellular glycogen, but had no effect on fungal pathogenicity. We found that loss of AGL1 and GPH1 led to a reduction in expression of TPS1 and TPS3, which encode components of the trehalose-6-phosphate synthase complex, that acts as a genetic switch in M. oryzae. Tps1 responds to glucose-6-phosphate levels and the balance of NADP/NADPH to regulate virulence-associated gene expression, in association with Nmr transcriptional inhibitors. We show that deletion of the NMR3 transcriptional inhibitor gene partially restores virulence to a Δagl1Δgph1 mutant, suggesting that glycogen metabolic genes are necessary for operation of the NADPH-dependent genetic switch in M. oryzae. PMID:24098112

  12. NACS Store Planning Manual.

    Science.gov (United States)

    College Store Journal, 1979

    1979-01-01

    Topics discussed by the NACS Store Planning/Renovation Committees in this updated version of the college store renovation manual include: short- and long-range planning, financial considerations, professional planning assistance, the store's image and business character, location considerations, building requirements, space requirements, fixtures,…

  13. 1H NMR visibility of mammalian glycogen in solution

    International Nuclear Information System (INIS)

    Zang, L.H.; Rothman, D.L.; Shulman, R.G.

    1990-01-01

    High-resolution 1 H NMR spectra of rabbit liver glycogen in 2 H 2 O were obtained at 500 MHz, and several resonances were assigned by comparison with the chemical shifts of α-linked diglucose molecules. The NMR relaxation times T 1 and T 2 of glycogen in 2 H 2 O were determined to be 1.1 and 0.029 s, respectively. The measured natural linewidth of the carbon-1 proton is in excellent agreement with that calculated from T 2 . The visibility measurements made by digesting glycogen and comparing glucose and glycogen signal intensities demonstrate that in spite of the very high molecular weight, all of the proton nuclei in glycogen contribute to the NMR spectrum. The result is not unexpected, since 100% NMR visibility was previously observed from the carbon nuclei of glycogen, due to the rapid intramolecular motions

  14. In vivo hepatic glycogen metabolism in the baboon

    International Nuclear Information System (INIS)

    Jehenson, P.; Canioni, P.; Hantraye, P.; Gueron, M.; Syrota, A.

    1988-01-01

    This paper describes hepatic glycogen synthesis from glucose studied in the baboon by C-13 MR spectroscopy at 2 T. Glycogen synthesis was followed for 3 hours on natural abundance spectra during glucose infusion. (1-C-13)-glucose (3g) was then injected. It produced a ten times larger rate of increase of glycogen-C 1 , which is much lower than expected, suggesting that glycogen synthesis mainly occurred from unlabeled gluconeogenic substrates. Signal-to-noise ratio was 50 for glycogen-C 1 on 2-minute H-1 decoupled spectra. Labeling of C 1 but also C 2 , C 5 and C 6 of glycogen indicated a 15% contribution of indirect pathways to its synthesis from glucose

  15. Analysis of genes involved in glycogen degradation in Escherichia coli.

    Science.gov (United States)

    Strydom, Lindi; Jewell, Jonathan; Meier, Michael A; George, Gavin M; Pfister, Barbara; Zeeman, Samuel; Kossmann, Jens; Lloyd, James R

    2017-02-01

    Escherichia coli accumulate or degrade glycogen depending on environmental carbon supply. Glycogen phosphorylase (GlgP) and glycogen debranching enzyme (GlgX) are known to act on the glycogen polymer, while maltodextrin phosphorylase (MalP) is thought to remove maltodextrins released by GlgX. To examine the roles of these enzymes in more detail, single, double and triple mutants lacking all their activities were produced. GlgX and GlgP were shown to act directly on the glycogen polymer, while MalP most likely catabolised soluble malto-oligosaccharides. Interestingly, analysis of a triple mutant lacking all three enzymes indicates the presence of another enzyme that can release maltodextrins from glycogen. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Qualitative and Quantitative Analyses of Glycogen in Human Milk.

    Science.gov (United States)

    Matsui-Yatsuhashi, Hiroko; Furuyashiki, Takashi; Takata, Hiroki; Ishida, Miyuki; Takumi, Hiroko; Kakutani, Ryo; Kamasaka, Hiroshi; Nagao, Saeko; Hirose, Junko; Kuriki, Takashi

    2017-02-22

    Identification as well as a detailed analysis of glycogen in human milk has not been shown yet. The present study confirmed that glycogen is contained in human milk by qualitative and quantitative analyses. High-performance anion exchange chromatography (HPAEC) and high-performance size exclusion chromatography with a multiangle laser light scattering detector (HPSEC-MALLS) were used for qualitative analysis of glycogen in human milk. Quantitative analysis was carried out by using samples obtained from the individual milks. The result revealed that the concentration of human milk glycogen varied depending on the mother's condition-such as the period postpartum and inflammation. The amounts of glycogen in human milk collected at 0 and 1-2 months postpartum were higher than in milk collected at 3-14 months postpartum. In the milk from mothers with severe mastitis, the concentration of glycogen was about 40 times higher than that in normal milk.

  17. Novel method for detection of glycogen in cells.

    Science.gov (United States)

    Skurat, Alexander V; Segvich, Dyann M; DePaoli-Roach, Anna A; Roach, Peter J

    2017-05-01

    Glycogen, a branched polymer of glucose, functions as an energy reserve in many living organisms. Abnormalities in glycogen metabolism, usually excessive accumulation, can be caused genetically, most often through mutation of the enzymes directly involved in synthesis and degradation of the polymer leading to a variety of glycogen storage diseases (GSDs). Microscopic visualization of glycogen deposits in cells and tissues is important for the study of normal glycogen metabolism as well as diagnosis of GSDs. Here, we describe a method for the detection of glycogen using a renewable, recombinant protein which contains the carbohydrate-binding module (CBM) from starch-binding domain containing protein 1 (Stbd1). We generated a fusion protein containing g lutathione S-transferase, a cM c eptitope and the tbd1 BM (GYSC) for use as a glycogen-binding probe, which can be detected with secondary antibodies against glutathione S-transferase or cMyc. By enzyme-linked immunosorbent assay, we demonstrate that GYSC binds glycogen and two other polymers of glucose, amylopectin and amylose. Immunofluorescence staining of cultured cells indicate a GYSC-specific signal that is co-localized with signals obtained with anti-glycogen or anti-glycogen synthase antibodies. GYSC-positive staining inside of lysosomes is observed in individual muscle fibers isolated from mice deficient in lysosomal enzyme acid alpha-glucosidase, a well-characterized model of GSD II (Pompe disease). Co-localized GYSC and glycogen signals are also found in muscle fibers isolated from mice deficient in malin, a model for Lafora disease. These data indicate that GYSC is a novel probe that can be used to study glycogen metabolism under normal and pathological conditions. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  18. Incorporation of metabolites into glycogen and lipids of the oyster, crassostrea virginica

    International Nuclear Information System (INIS)

    Swift, M.L.; Humphrey, C.L.

    1987-01-01

    Groups of oysters, either fed or unfed, were exposed to U- 14 C labelled D-glucose, L-asp, L-leu, L-ala or acetate for 6 hrs. Except for the glucose trials, the disappearance of radioactivity from the saline of the unfed oysters was greater (83%) than for the fed animals (65%). With glucose, 88% of the radioactivity disappeared in each trial. The specific radioactivity of glycogen isolated from oysters exposed to labelled glucose, asp and ala was 1283, 468 and 8.22 dpm/mg glycogen respectively. Radioactivity was found primarily in the triacylglycerols and phospholipids (PL) in fed oysters and in PL only in unfed oysters. Phosphatidyl choline, phosphatidyl ethanolamine, and a fraction containing phosphatidyl serine and phosphatidyl inositol, had 32%, 25% and 35-40% of the radioactivity respectively. Incorporation of total radioactivity into PL was 70% lower in unfed vs. fed trials, but the distribution of counts among the phospholipids classes was unchanged. Glycogenesis does not appear to be a significant pathway in the oyster. Apparently well-fed oysters are able to store excess dietary calories as lipid. During periods of starvation exogenous small metabolites along with glucose from glycogen are catabolized

  19. Glutamate Cysteine Ligase—Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage

    KAUST Repository

    Lavoie, Suzie

    2016-04-21

    Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.

  20. Glutamate Cysteine Ligase—Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage

    KAUST Repository

    Lavoie, Suzie; Steullet, Pascal; Kulak, Anita; Preitner, Frederic; Do, Kim Q.; Magistretti, Pierre J.

    2016-01-01

    Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.

  1. Tyrosine glycosylation is involved in muscle-glycogen synthesis

    International Nuclear Information System (INIS)

    Rodriguez, I.R.; Tandecarz, J.S.; Kirkman, B.R.; Whelan, W.J.

    1986-01-01

    Rabbit-muscle glycogen contains a covalently bound protein having Mr 37,000 that the authors will henceforth refer to as glycogenin. It is completely insoluble in water at pH 5, and may be generated as a precipitate as a result of the combined action on glycogen of α-amylase and glucoamylase, or by treatment with anhydrous hydrogen fluoride. In the former case the protein still carries some of the glucose residues of glycogen (10-30 per mole of glycogenin). The linkage between glycogen and glycogenin has been identified as a novel glycosidic-amino acid bond. The authors demonstrated glucosylation with UDP[/sup 14/C]glucose by a muscle extract of two rabbit-muscle proteins contained in the same extract. The relation of these proteins to glycogenin, and whether the amino acid undergoing glucosylation is tyrosine, remains to be explored. The discovery of glycogenin is, the authors believe, an important clue to the mechanism of biogenesis of glycogen and may represent a previously unsuspected means of metabolic control of the glycogen content of the cell and the location of glycogen within the cell. The facts that the linkage between glycogen and glycogenin is via tyrosine, that insulin stimulates glycogen synthesis, and acts on its receptor by causing it to become an active tyrosine kinase, may be linked by a common thread

  2. Extraction of glycogen on mild condition lacks AIG fraction.

    Science.gov (United States)

    Ghafouri, Z; Rasouli, M

    2016-12-01

    Extraction of animal tissues with cold water or perchloric acid yields less glycogen than is obtained with hot-alkaline. Extraction with acid and alkaline gives two fractions, acid soluble (ASG) and insoluble glycogen (AIG). The aim of this work is to examine the hypothesis that not all liver glycogen is extractable by Tris-buffer using current techniques. Rat liver was homogenized with Tris-buffer pH 8.3 and extracted for the glycogen fractions, ASG and AIG. The degree of homogenization was changed to remove all glycogen. The content of glycogen was 47.7 ± 1.2 and 11.6 ± 0.8 mg/g wet liver in the supernatant and pellet of the first extraction respectively. About 24% of total glycogen is lost through the first pellet. Increasing the extent of homogenization from 30 to 180 sec and from 15000 to 20000 rpm followed with 30 sec ultrasonication did not improve the extraction. ASG and AIG constitute about 77% and 23% of the pellet glycogen respectively. Extraction with cold Tris-buffer failed to extract glycogen completely.  Increasing the extent of homogenization followed with ultrasonication also did not improve the extraction. Thus it is necessary to re-examine the previous findings obtained by extraction with cold Tris-buffer.

  3. Modeling Replenishment of Ultrathin Liquid Perfluoro polyether Z Films on Solid Surfaces Using Monte Carlo Simulation

    International Nuclear Information System (INIS)

    Mayeed, M.S.; Kato, T.

    2014-01-01

    Applying the reptation algorithm to a simplified perfluoro polyether Z off-lattice polymer model an NVT Monte Carlo simulation has been performed. Bulk condition has been simulated first to compare the average radius of gyration with the bulk experimental results. Then the model is tested for its ability to describe dynamics. After this, it is applied to observe the replenishment of nano scale ultrathin liquid films on solid flat carbon surfaces. The replenishment rate for trenches of different widths (8, 12, and 16 nms for several molecular weights) between two films of perfluoro polyether Z from the Monte Carlo simulation is compared to that obtained solving the diffusion equation using the experimental diffusion coefficients of Ma et al. (1999), with room condition in both cases. Replenishment per Monte Carlo cycle seems to be a constant multiple of replenishment per second at least up to 2 nm replenished film thickness of the trenches over the carbon surface. Considerable good agreement has been achieved here between the experimental results and the dynamics of molecules using reptation moves in the ultrathin liquid films on solid surfaces.

  4. Diurnal variation in glycogen phosphorylase activity in rat liver. A quantitative histochemical study

    NARCIS (Netherlands)

    Frederiks, W. M.; Marx, F.; Bosch, K. S.

    1987-01-01

    The diurnal variations of the glycogen content and of glycogen phosphorylase activity in periportal and pericentral areas of rat liver parenchyma have been analyzed in periodic acid Schiff (PAS)-stained cryostat sections using quantitative microdensitometry. Glycogen content and phosphorylase

  5. Volume I. Glycogen: A historical overview, an adjunct to thesis. Volume II. Non-glucose components of glycogen

    International Nuclear Information System (INIS)

    Kirkman, B.R.

    1988-01-01

    Investigations have been carried out on three non-glucose components of native glycogen: protein, glucosamine, and phosphate. The protein, glycogenin, appears to serve as the primer upon which new molecules of glycogen are synthesized. When cell extracts are incubated with ( 14 C)UDPG, ( 14 C)glucose becomes transferred onto pre-existing chains of alpha-1,4 linked glucose associated with free glycogenin. The transferase and glycogenin remain associated during various purification steps. Liver glycogen appears to contain less than 0.02% protein which may correspond to the presence of one molecule of glycogenin (37 kDa) per alpha particle of liver glycogen. The core beta particle within each alpha particle may be synthesized upon glycogenin, while the remaining 20-40 beta particles may arise from each other. The author has demonstrated the natural occurrence of glucosamine in liver glycogen (but not muscle glycogen) from various species in an amount of about one molecule per molecule of glycogen. The glucosamine is underivatized, appears to be randomly scattered in the glycogen, and may be derived from dietary galactosamine. Similar to Fontana (1980), the author observed that native liver glycogen could be fractionated on DEAE-cellulose apparently on the basis of phosphate content. The more strongly bound glycogen possessed a greater molecular weight and content of glucosamine and phosphate. Possible explanations for these subfractions are considered. The phosphate appears to be concentrated near the center of the glycogen molecules. About 30% appears to be associated with glucose-6P and the remainder with an unidentified phosphodiester. The phosphate may stimulate glycogen synthesis. How the phosphate becomes incorporated is unknown

  6. A highly prevalent equine glycogen storage disease is explained by constitutive activation of a mutant glycogen synthase

    DEFF Research Database (Denmark)

    Maile, C A; Hingst, Janne Rasmuss; Mahalingan, K K

    2017-01-01

    BACKGROUND: Equine type 1 polysaccharide storage myopathy (PSSM1) is associated with a missense mutation (R309H) in the glycogen synthase (GYS1) gene, enhanced glycogen synthase (GS) activity and excessive glycogen and amylopectate inclusions in muscle. METHODS: Equine muscle biochemical...... had significantly higher glycogen content than control horse muscle despite no difference in GS expression. GS activity was significantly higher in muscle from homozygous mutants than from heterozygote and control horses, in the absence and presence of the allosteric regulator, glucose 6 phosphate (G6...

  7. Glycogen synthesis in human gastrocnemius muscle is not representative of whole-body muscle glycogen synthesis.

    NARCIS (Netherlands)

    Serlie, M.J.; Haan, J.H.A. de; Tack, C.J.J.; Verberne, H.J.; Ackermans, M.T.; Heerschap, A.; Sauerwein, H.P.

    2005-01-01

    The introduction of 13C magnetic resonance spectroscopy (MRS) has enabled noninvasive measurement of muscle glycogen synthesis in humans. Conclusions based on measurements by the MRS technique assume that glucose metabolism in gastrocnemius muscle is representative for all skeletal muscles and thus

  8. Glycogen synthesis in human gastrocnemius muscle is not representative of whole-body muscle glycogen synthesis

    NARCIS (Netherlands)

    Serlie, Mireille J. M.; de Haan, Jacco H.; Tack, Cees J.; Verberne, Hein J.; Ackermans, Mariette T.; Heerschap, Arend; Sauerwein, Hans P.

    2005-01-01

    The introduction of C-13 magnetic resonance spectroscopy (MRS) has enabled noninvasive measurement of muscle glycogen synthesis in humans. Conclusions based on measurements by the MRS technique assume that glucose metabolism in gastrocnemius muscle is representative for all skeletal muscles and thus

  9. Glycogen Synthase Kinase-3 is involved in glycogen metabolism control and embryogenesis of Rhodnius prolixus.

    Science.gov (United States)

    Mury, Flávia B; Lugon, Magda D; DA Fonseca, Rodrigo Nunes; Silva, Jose R; Berni, Mateus; Araujo, Helena M; Fontenele, Marcio Ribeiro; Abreu, Leonardo Araujo DE; Dansa, Marílvia; Braz, Glória; Masuda, Hatisaburo; Logullo, Carlos

    2016-10-01

    Rhodnius prolixus is a blood-feeding insect that transmits Trypanosoma cruzi and Trypanosoma rangeli to vertebrate hosts. Rhodnius prolixus is also a classical model in insect physiology, and the recent availability of R. prolixus genome has opened new avenues on triatomine research. Glycogen synthase kinase 3 (GSK-3) is classically described as a key enzyme involved in glycogen metabolism, also acting as a downstream component of the Wnt pathway during embryogenesis. GSK-3 has been shown to be highly conserved among several organisms, mainly in the catalytic domain region. Meanwhile, the role of GSK-3 during R. prolixus embryogenesis or glycogen metabolism has not been investigated. Here we show that chemical inhibition of GSK-3 by alsterpaullone, an ATP-competitive inhibitor of GSK3, does not affect adult survival rate, though it alters oviposition and egg hatching. Specific GSK-3 gene silencing by dsRNA injection in adult females showed a similar phenotype. Furthermore, bright field and 4'-6-diamidino-2-phenylindole (DAPI) staining analysis revealed that ovaries and eggs from dsGSK-3 injected females exhibited specific morphological defects. We also demonstrate that glycogen content was inversely related to activity and transcription levels of GSK-3 during embryogenesis. Lastly, after GSK-3 knockdown, we observed changes in the expression of the Wingless (Wnt) downstream target β-catenin as well as in members of other pathways such as the receptor Notch. Taken together, our results show that GSK-3 regulation is essential for R. prolixus oogenesis and embryogenesis.

  10. Muscular glycogen storage diseases without increased glycogen content on histoplathological examination

    NARCIS (Netherlands)

    Hoeksma, M.; den Dunnen, W. F. A.; Niezen-Koning, K. E.; van Diggelen, O. P.; van Spronsen, F. J.

    Histopathological findings of muscle biopsies from five patients with two different muscular glycogen storage diseases (mGSD) were presented. From these investigations it emerged that the yield of histopathology in mGSD is low. In only one of five patients histopathological findings gave a clue

  11. A systematic literature review on the joint replenishment problem solutions: 2006-2015

    Directory of Open Access Journals (Sweden)

    Leonardo dos Santos Lourenço Bastos

    Full Text Available Abstract Among all existing inventory replenishment models, this research was dedicated to the Joint Replenishment Problem (JRP, which consists in the replenishment of multiple items simultaneously, aiming total cost reduction. Literature has presented several optimal and approximated solutions to this problem, with different applications and techniques, which results in a large quantity of solution proposals. Therefore, this research aimed to map existing solutions to the problem in 2006-2015 in order to provide a guide for interested parts in JRP and to update previous reviews. Hence, systematic review was used to assess papers from that period interval. From a total of 128 papers, a general trend for seeking JRP extensions and practical applications was verified. Furthermore, the heuristic and metaheuristic methods were the most used and considered the most suitable due to their simplicity in understanding and application.

  12. Stimulation of flower nectar replenishment by removal: A survey of eleven animal-pollinated plant species

    Directory of Open Access Journals (Sweden)

    Elaine Y Luo

    2014-02-01

    Full Text Available Understanding the interaction between reward-seeking flower feeding animals and plants requires consideration of the dynamic nature of nectar secretion. Studies on several plants suggest that nectar secretion may increase in response to its removal, but it is not clear whether the phenomenon is widespread. We determined whether 11 species of Colorado mountain wildflowers showed removal-enhanced nectar replenishment (RENR. We measured floral phenology, nectar volumes, rate of replenishment, and compared the cumulative nectar produced following five hourly removals with that accumulated after five hours. Nectar replenishment occurred rapidly, within minutes; statistically significant RENR was observed in 9 of our 11 study species, with the strongest effects in bee-pollinated species. We discuss the implications of RENR in plant species on the measurement of nectar, the adaptive advantage of RENR, and the energetic costs of RENR.

  13. Optimal pricing and replenishment policies for instantaneous deteriorating items with backlogging and trade credit under inflation

    Science.gov (United States)

    Sundara Rajan, R.; Uthayakumar, R.

    2017-12-01

    In this paper we develop an economic order quantity model to investigate the optimal replenishment policies for instantaneous deteriorating items under inflation and trade credit. Demand rate is a linear function of selling price and decreases negative exponentially with time over a finite planning horizon. Shortages are allowed and partially backlogged. Under these conditions, we model the retailer's inventory system as a profit maximization problem to determine the optimal selling price, optimal order quantity and optimal replenishment time. An easy-to-use algorithm is developed to determine the optimal replenishment policies for the retailer. We also provide optimal present value of profit when shortages are completely backlogged as a special case. Numerical examples are presented to illustrate the algorithm provided to obtain optimal profit. And we also obtain managerial implications from numerical examples to substantiate our model. The results show that there is an improvement in total profit from complete backlogging rather than the items being partially backlogged.

  14. Information for Stores Users

    CERN Multimedia

    Logistics Group

    2004-01-01

    As the FARNELL Catalogue CAPACITORS, RESISTORS and POTENTIOMETERS have now been integrated into the CERN Stores Catalogue (SCEM Groups 10 and 11) they can now be obtained via an EDH 'Material Request' like any other Stores item. N.B. The Farnell 'Order code' is one of the key-words that make it easier to find items in the Stores Catalogue. Logistics Group FI Department

  15. Distributed energy store railgun

    International Nuclear Information System (INIS)

    Marshall, R.A.

    1991-01-01

    This paper reports that when the limiting case of a distributed energy store railgun is analyzed, i.e., the case where the space between adjacent energy stores become indefinitely small, three important results are obtained. First, the shape of the current pulse delivered by each store is sinusoidal and an exponential tail. Second, the rail-to-rail voltage behind the rear-most active store approaches zero. Third, it is not possible to choose parameters in such a way that capacitor crowbars can be eliminated

  16. Model of inventory replenishment in periodic review accounting for the occurrence of shortages

    Directory of Open Access Journals (Sweden)

    Stanisław Krzyżaniak

    2014-03-01

    Full Text Available Background: Despite the development of alternative concepts of goods flow management, the inventory management under conditions of random variations of demand is still an important issue, both from the point of view of inventory keeping and replenishment costs and the service level measured as the level of inventory availability. There is a number of inventory replenishment systems used in these conditions, but they are mostly developments of two basic systems: reorder point-based and periodic review-based. The paper deals with the latter system. Numerous researches indicate the need to improve the classical models describing that system, the reason being mainly the necessity to adapt the model better to the actual conditions. This allows a correct selection of parameters that control the used inventory replenishment system and - as a result - to obtain expected economic effects. Methods: This research aimed at building a model of the periodic review system to reflect the relations (observed during simulation tests between the volume of inventory shortages and the degree of accounting for so-called deferred demand, and the service level expressed as the probability of satisfying the demand in the review and the inventory replenishment cycle. The following model building and testing method has been applied: numerical simulation of inventory replenishment - detailed analysis of simulation results - construction of the model taking into account the regularities observed during the simulations - determination of principles of solving the system of relations creating the model - verification of the results obtained from the model using the results from simulation. Results: Presented are selected results of calculations based on classical formulas and using the developed model, which describe the relations between the service level and the parameters controlling the discussed inventory replenishment system. The results are compared to the simulation

  17. Functional significance of brain glycogen in sustaining glutamatergic neurotransmission

    DEFF Research Database (Denmark)

    Sickmann, Helle M; Walls, Anne B; Schousboe, Arne

    2009-01-01

    The involvement of brain glycogen in sustaining neuronal activity has previously been demonstrated. However, to what extent energy derived from glycogen is consumed by astrocytes themselves or is transferred to the neurons in the form of lactate for oxidative metabolism to proceed is at present u...

  18. Free fatty acids increase hepatic glycogen content in obese males

    NARCIS (Netherlands)

    Allick, G.; Sprangers, F.; Weverling, G. J.; Ackermans, M. T.; Meijer, A. J.; Romijn, J. A.; Endert, E.; Bisschop, P. H.; Sauerwein, H. P.

    2004-01-01

    Obesity is associated with increased hepatic glycogen content. In vivo and in vitro data suggest that plasma free fatty acids (FFA) may cause this increase. In this study we investigated the effect of physiological plasma FFA levels on hepatic glycogen metabolism by studying intrahepatic glucose

  19. Glucose 6-phosphate compartmentation and the control of glycogen synthesis

    NARCIS (Netherlands)

    Meijer, Alfred

    2002-01-01

    Using adenovirus-mediated gene transfer into FTO-2B cells, a rat hepatoma cell line, we have overexpressed hexokinase I, (HK I), glucokinase (GK), liver glycogen synthase (LGS), muscle glycogen synthase (MGS), and combinations of each of the two glucose phosphorylating enzymes with each one of the

  20. Muscle glycogen and cell function--Location, location, location.

    Science.gov (United States)

    Ørtenblad, N; Nielsen, J

    2015-12-01

    The importance of glycogen, as a fuel during exercise, is a fundamental concept in exercise physiology. The use of electron microscopy has revealed that glycogen is not evenly distributed in skeletal muscle fibers, but rather localized in distinct pools. In this review, we present the available evidence regarding the subcellular localization of glycogen in skeletal muscle and discuss this from the perspective of skeletal muscle fiber function. The distribution of glycogen in the defined pools within the skeletal muscle varies depending on exercise intensity, fiber phenotype, training status, and immobilization. Furthermore, these defined pools may serve specific functions in the cell. Specifically, reduced levels of these pools of glycogen are associated with reduced SR Ca(2+) release, muscle relaxation rate, and membrane excitability. Collectively, the available literature strongly demonstrates that the subcellular localization of glycogen has to be considered to fully understand the role of glycogen metabolism and signaling in skeletal muscle function. Here, we propose that the effect of low muscle glycogen on excitation-contraction coupling may serve as a built-in mechanism, which links the energetic state of the muscle fiber to energy utilization. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Exercise intolerance in Glycogen Storage Disease Type III

    DEFF Research Database (Denmark)

    Preisler, Nicolai; Pradel, Agnès; Husu, Edith

    2013-01-01

    Myopathic symptoms in Glycogen Storage Disease Type IIIa (GSD IIIa) are generally ascribed to the muscle wasting that these patients suffer in adult life, but an inability to debranch glycogen likely also has an impact on muscle energy metabolism. We hypothesized that patients with GSD IIIa can...

  2. COLLABORATION BETWEEN SMALL RETAIL STORES AND SUPPLIERS OF FOOD PRODUCTS

    Directory of Open Access Journals (Sweden)

    Lenka Branska

    2017-01-01

    Full Text Available Small grocery stores are forced to look for ways to retain customers. One possibility is through collaboration with suppliers. Therefore, the aim of this research was to determine the forms of collaboration between small Czech grocery stores and suppliers and to specify the differences in this collaboration depending on store location and the possible affiliation of the store with a retail chain. To achieve this goal, quantitative research was carried out among 65 Czech retail stores using face-to-face interviews with predetermined questions. Collaboration was assessed on the basis of four criteria defined by the authors. It was found that the most frequently occurring element of collaboration was the provision of trade credit to retailers – less often, long-term contracts and synchronization of replenishment. The least used was information sharing. The research results show that the form of collaboration is significantly affected by customer value. Therefore, the level of collaboration can be improved by building horizontally interconnected retail chains. The paper enriches theoretical knowledge by specifying possible elements of collaboration between small retail stores and suppliers and mapping the frequency of their implementation.

  3. Muscle glycogen and cell function - Location, location, location

    DEFF Research Database (Denmark)

    Ørtenblad, N; Nielsen, Joachim

    2015-01-01

    The importance of glycogen, as a fuel during exercise, is a fundamental concept in exercise physiology. The use of electron microscopy has revealed that glycogen is not evenly distributed in skeletal muscle fibers, but rather localized in distinct pools. In this review, we present the available...... evidence regarding the subcellular localization of glycogen in skeletal muscle and discuss this from the perspective of skeletal muscle fiber function. The distribution of glycogen in the defined pools within the skeletal muscle varies depending on exercise intensity, fiber phenotype, training status......, and immobilization. Furthermore, these defined pools may serve specific functions in the cell. Specifically, reduced levels of these pools of glycogen are associated with reduced SR Ca(2+) release, muscle relaxation rate, and membrane excitability. Collectively, the available literature strongly demonstrates...

  4. Postdoctoral Fellowship for Dr. Lindholm, Underwater Physiology and Medicine

    National Research Council Canada - National Science Library

    Lundgren, Claes E; Pendergast, David R

    2008-01-01

    .... Two studies showed the potential for increased risk of loss of consciousness (LOC) during breath-holing when carbohydrate stores were reduced by either dietary restriction or exercise without proper replenishment of glucose and glycogen...

  5. Predicting Commissary Store Success

    Science.gov (United States)

    2014-12-01

    stores or if it is possible to predict that success. Multiple studies of private commercial grocery consumer preferences , habits and demographics have...appropriate number of competitors due to the nature of international cultures and consumer preferences . 2. Missing Data Four of the remaining stores

  6. Storing up trouble

    International Nuclear Information System (INIS)

    Townsley, M.

    1992-01-01

    Scottish Nuclear have applied for permission to build a temporary ground-level dry store for spent fuel at Torness. However, Nirex's failure to find a suitable site for a long-term repository could mean that the Torness store will be less temporary than planned. (author)

  7. Synthesis of glycogen from fructose in the presence of elevated levels of glycogen phosphorylase a in rat hepatocytes.

    Science.gov (United States)

    Ciudad, C J; Massagué, J; Salavert, A; Guinovart, J J

    1980-03-20

    Incubation of hepatocytes with glucose promoted the increase in the glycogen synthase (-glucose 6-phosphate/+glucose 6-phosphate) activity ratio, the decrease in the levels of phosphorylase a and a marked increase in the intracellular glycogen level. Incubation with fructose alone promoted the simultaneous activation of glycogen synthase and increase in the levels of phosphorylase a. Strikingly, glycogen deposition occurred in spite of the elevated levels of phosphorylase a. When glucose and fructose were added to the media the activation of glycogen synthase was always higher than when the hexoses were added separately. On the other hand the effects on glycogen phosphorylase were a function of the relative concentrations of both sugars. Inactivation of glycogen phosphorylase occurred when the fructose to glucose ratio was low while activation took place when the ratio was high. The simultaneous presence of glucose and fructose resulted, in all cases, in an enhancement in the deposition of glycogen. The effects described were not limited to fructose as D-glyceraldehyde, dihydroxyacetone, L-sorbose, D-tagatose and sorbitol, compounds metabolically related to fructose, provoked the same behaviour.

  8. GLYCOGEN IN BACILLUS-SUBTILIS - MOLECULAR CHARACTERIZATION OF AN OPERON ENCODING ENZYMES INVOLVED IN GLYCOGEN BIOSYNTHESIS AND DEGRADATION

    NARCIS (Netherlands)

    KIEL, JAKW; BOELS, JM; BELDMAN, G; VENEMA, G

    Although it has never been reported that Bacillus subtilis is capable of accumulating glycogen, we have isolated a region from the chromosome of B. subtilis containing a glycogen operon. The operon is located directly downstream from trnB, which maps at 275 degrees on the B. subtilis chromosome. It

  9. Information for stores users

    CERN Multimedia

    Logistics Group - FI Department

    2005-01-01

    The Farnell catalogue can now be accessed from the Material Request form on EDH in addition to the CERN Stores catalogue. Users can order Farnell equipment as well as standard Stores equipment at the same time using a single document, the EDH Materials Request form. The Materials Request form offers users items from both the internal 'Stores' catalogue and the external 'Farnell' catalogue, all of which may be ordered on the same form. The system automatically forwards orders for standard Stores equipment to the CERN Stores and those for Farnell equipment to Farnell. The delivery time is 48 hours in both cases. Requests for materials are routed for approval in accordance with the standard EDH routing procedures. Logistics Group FI Department

  10. Suboptimal and optimal order policies for fixed and varying replenishment interval with declining market

    Science.gov (United States)

    Yu, Jonas C. P.; Wee, H. M.; Yang, P. C.; Wu, Simon

    2016-06-01

    One of the supply chain risks for hi-tech products is the result of rapid technological innovation; it results in a significant decline in the selling price and demand after the initial launch period. Hi-tech products include computers and communication consumer's products. From a practical standpoint, a more realistic replenishment policy is needed to consider the impact of risks; especially when some portions of shortages are lost. In this paper, suboptimal and optimal order policies with partial backordering are developed for a buyer when the component cost, the selling price, and the demand rate decline at a continuous rate. Two mathematical models are derived and discussed: one model has the suboptimal solution with the fixed replenishment interval and a simpler computational process; the other one has the optimal solution with the varying replenishment interval and a more complicated computational process. The second model results in more profit. Numerical examples are provided to illustrate the two replenishment models. Sensitivity analysis is carried out to investigate the relationship between the parameters and the net profit.

  11. A hybrid replenishment model, the best fit in fast growing industries

    NARCIS (Netherlands)

    Hartevelt, R.

    2011-01-01

    During the design supply chain control processes, balancing cost versus service plays an important role. To select the most suitable replenishment strategy is the main enabler in reaching the goal of finding the optimal balance. In this article a framework is developed which will help to select the

  12. The effect of replenishment policies on the bullwhip effect : a transfer function approach

    NARCIS (Netherlands)

    Jaksic, M.; Rusjan, B.

    2008-01-01

    An important phenomenon in supply chain management, known as the bullwhip effect, suggests that demand variability increases as one moves up a supply chain. This paper examines the influence of different replenishment policies on the occurrence of the bullwhip effect. The paper demonstrates that

  13. Financing University Education in Nigeria : a Proposal for Infrastructure Replenishment in Universities

    Directory of Open Access Journals (Sweden)

    Virtue U. Ekhosuehi

    2016-01-01

    Full Text Available The subject of replenishment of infrastructure in Nigerian public universities has been of great concern to stakeholders in the educational system. How to obtain an appropriate replenishment plan that would give the desired infrastructure for a university after a certain period of time is a long-standing problem. We attempt to find a solution to this problem from an engineering perspective based on optimal control theory. The revenue generated through the payment of school fees and the costs of investment in infrastructure are used to construct the objective function. The state variables are the amount budgeted for such an investment and the stock of infrastructure, while the rate of replenishment is used as the control variable. The problem is solved by utilising Pontryagin's principle. The dynamics of the replenishment plan is illustrated with an example. The results show that there should be a steady in-crease in the amount budgeted, in order to attain the desired infrastructure. (original abstract

  14. AN OPTIMAL REPLENISHMENT POLICY FOR DETERIORATING ITEMS WITH RAMP TYPE DEMAND UNDER PERMISSIBLE DELAY IN PAYMENTS

    Directory of Open Access Journals (Sweden)

    Dr. Sanjay Jain

    2010-10-01

    Full Text Available The aim of this paper is to develop an optimal replenishment policy for inventory models of deteriorating items with ramp type demand under permissible delay in payments. Deterioration of items begins on their arrival in stock.  An example is also presented to illustrate the application of developed model.

  15. The Multi-Location Transshipment Problem with Positive Replenishment Lead Times

    NARCIS (Netherlands)

    Y. Gong (Yeming); E. Yucesan

    2006-01-01

    textabstractTransshipments, monitored movements of material at the same echelon of a supply chain, represent an effective pooling mechanism. With a single exception, research on transshipments overlooks replenishment lead times. The only approach for two-location inventory systems with

  16. 75 FR 62345 - Minimum Balance Requirement and Automatic Replenishment Option for Deposit Account Holders

    Science.gov (United States)

    2010-10-08

    ... may establish a deposit account, make advance deposits into that account, and charge copyright fees... for copyright registration paid for by deposit account debits be submitted using the electronic... assesses service charges for deposit account overdrafts ($165) and dishonored deposit account replenishment...

  17. A replenishment policy for a perishable inventory system based on estimated aging and retrieval behavior

    NARCIS (Netherlands)

    Broekmeulen, R.A.C.M.; Donselaar, van K.H.

    2007-01-01

    So far the literature on inventory control for perishable products has mainly focused on (near-) optimal replenishment policies for a stylized environment, assuming no leadtime, no lot-sizing, stationary demand, a first in first out retrieval policy and/or product life time equal to two periods.

  18. MILP for the Inventory and Routing for Replenishment Problem in the Car Assembly Line.

    Directory of Open Access Journals (Sweden)

    Raul Pulido

    2014-01-01

    Full Text Available The inbound logistic for feeding the workstation inside the factory represents a critical issue in the car manufacturing industry. Nowadays, this issue is even more critical than in the past since more types of car are being produced in the assembly lines. Consequently, as workstations have to install many types of components, they also need to have an inventory of different types of the component in a compact space.The replenishment is a critical issue since a lack of inventory could cause line stoppage or reworking. On the other hand, an excess of inventory could increase the holding cost or even block the replenishment paths. The decision of the replenishment routes cannot be made without taking into consideration the inventory needed by each station during the production time which will depend on the production sequence. This problem deals with medium-sized instances and it is solved using online solvers. The contribution of this paper is a MILP for the replenishment and inventory of the components in a car assembly line.

  19. 12 CFR 221.116 - Bank loans to replenish working capital used to purchase mutual fund shares.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Bank loans to replenish working capital used to... Bank loans to replenish working capital used to purchase mutual fund shares. (a) In a situation... period of time the result would be the same. Accordingly, the Board concluded that bank loans made under...

  20. Glycogen synthase from the parabasalian parasite Trichomonas vaginalis: An unusual member of the starch/glycogen synthase family.

    Science.gov (United States)

    Wilson, Wayne A; Pradhan, Prajakta; Madhan, Nayasha; Gist, Galen C; Brittingham, Andrew

    2017-07-01

    Trichomonas vaginalis, a parasitic protist, is the causative agent of the common sexually-transmitted infection trichomoniasis. The organism has long been known to synthesize substantial glycogen as a storage polysaccharide, presumably mobilizing this compound during periods of carbohydrate limitation, such as might be encountered during transmission between hosts. However, little is known regarding the enzymes of glycogen metabolism in T. vaginalis. We had previously described the identification and characterization of two forms of glycogen phosphorylase in the organism. Here, we measure UDP-glucose-dependent glycogen synthase activity in cell-free extracts of T. vaginalis. We then demonstrate that the TVAG_258220 open reading frame encodes a glycosyltransferase that is presumably responsible for this synthetic activity. We show that expression of TVAG_258220 in a yeast strain lacking endogenous glycogen synthase activity is sufficient to restore glycogen accumulation. Furthermore, when TVAG_258220 is expressed in bacteria, the resulting recombinant protein has glycogen synthase activity in vitro, transferring glucose from either UDP-glucose or ADP-glucose to glycogen and using both substrates with similar affinity. This protein is also able to transfer glucose from UDP-glucose or ADP-glucose to maltose and longer oligomers of glucose but not to glucose itself. However, with these substrates, there is no evidence of processivity and sugar transfer is limited to between one and three glucose residues. Taken together with our earlier work on glycogen phosphorylase, we are now well positioned to define both how T. vaginalis synthesizes and utilizes glycogen, and how these processes are regulated. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  1. Muscle and liver glycogen utilization during prolonged lift and carry exercise: male and female responses.

    Science.gov (United States)

    Price, Thomas B; Sanders, Kimberly

    2017-02-01

    This study examined the use of carbohydrates by men and women during lift/carry exercise. Effects of menstrual cycle variation were examined in women. Twenty-five subjects (15 M, 10 F) were studied; age 25 ± 2y M, 26 ± 3y F, weight 85 ± 3 kg* M, 63 ± 3 kg F, and height 181 ± 2 cm* M, 161 ± 2 cm F (* P  Glycogen utilization was tracked with natural abundance C-13 NMR of quadriceps femoris and biceps brachialis muscles, and in the liver at rest and throughout the exercise period. Males completed more of the 180 min protocol than females [166 ± 9 min M, 112 ± 16 min* F (L), 88 ± 16 min** F (F) (* P  = 0.0036, ** P  glycogen depletion was similar between sexes and within females in L/F phases [4.7 ± 0.8 mmol/L-h M, 4.5 ± 2.4 mmol/L-h F (L), 10.3 ± 3.5 mmol/L-h F (F)]. Biceps glycogen depletion was greater in females [2.7 ± 0.9 mmol/L-h M, 10.3 ± 1.3 mmol/L-h* F (L), 16.8 ± 4.8 mmol/L-h** F (F) (* P  = 0.0004, ** P  = 0.0122)]. Resting glycogen levels were higher in females during the follicular phase ( P  = 0.0077). Liver glycogen depletion increased during exercise, but was not significant. We conclude that with non-normalized lift/carry exercise: (1) Based on their smaller size, women are less capable of completing and work their upper body harder than men. (2) Women and men work their lower body at similar levels. (3) Women store more quadriceps carbohydrate during the follicular phase. (4) The liver is not significantly challenged by this protocol. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  2. Glycogen and glucose metabolism are essential for early embryonic development of the red flour beetle Tribolium castaneum.

    Directory of Open Access Journals (Sweden)

    Amanda Fraga

    Full Text Available Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3 and hexokinase (HexA genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen.

  3. Information for stores users

    CERN Multimedia

    2007-01-01

    From next week, the SFS UNIMARKET (tooling) catalogue will be accessible using the Material Request form on EDH in addition to the CERN Stores catalogue and those of existing suppliers. Users will now be able to place orders from the SFS catalogue using the Material Request form on EDH. Note: The system automatically forwards orders for standard Stores equipment and those for SFS equipment, placed using the same Material Request form, to the CERN Stores and SFS respectively. In both cases, the maximum delivery time will be 48 hours. Requests for equipment will be routed for approval in accordance with standard EDH routing procedures. Logistics Group FI Department

  4. INFORMATION FOR STORES USERS

    CERN Multimedia

    2007-01-01

    From next week, the SFS UNIMARKET (tooling) catalogue will be accessible using the Material Request form on EDH in addition to the CERN Stores catalogue and those of existing suppliers. Users will now be able to place orders from the SFS catalogue using the Material Request form on EDH. Note: The system automatically forwards orders for standard Stores equipment and those for SFS equipment, placed using the same Material Request form, to the CERN Stores and SFS respectively. In both cases, the maximum delivery time will be 48 hours. Requests for equipment will be routed for approval in accordance with standard EDH routing procedures. Logistics Group FI Department

  5. Information for stores users

    CERN Multimedia

    2006-01-01

    The Radiospares Catalogue is now accessible from the Material Request page on EDH in the same way as the CERN Stores Catalogue. This means that users can order Radiospares equipment by completing an EDH Materials Request form. N.B.: The system will automatically forward orders for standard Stores equipment to the CERN Stores and those for Radiospares equipment to Radiospares. In both cases the delivery time will be a maximum of 48 hours. Requests for materials will be routed for approval in accordance with the standard EDH routing procedures. Logistics Group FI Department

  6. INFORMATION FOR STORES USERS

    CERN Multimedia

    SPL Division

    1999-01-01

    You can now make Material Request from CERN Stores over the WEB :CERN Home/Administrative Tools/EDH/Material Requestor https://edh.cern.ch/Document/MAGVia the Stores Catalogue : CERN Home/Administrative Tools/Stores Catalogueor http://edhcat.cern.ch/In both cases, you need to enter your EDH login and password.For more details, you can consult the Quick Reference Guide on :http://edh.cern.ch/doc/quickrefguides.htmlor obtain a printed version from AIS Support at tel: 79933or e-mail to: ais.support@cern.chSPL DivisionLogistics Group

  7. On the risks from sediment and overlying water by replenishing urban landscape ponds with reclaimed wastewater.

    Science.gov (United States)

    Ao, Dong; Chen, Rong; Wang, Xiaochang C; Liu, Yanzheng; Dzakpasu, Mawuli; Zhang, Lu; Huang, Yue; Xue, Tao; Wang, Nan

    2018-05-01

    The extensive use of reclaimed wastewater (RW) as a source of urban landscape pond replenishment, stimulated by the lack of surface water (SW) resources, has raised public concern. Greater attention should be paid to pond sediments, which act as 'sinks' and 'sources' of contaminants to the overlying pond water. Three ponds replenished with RW (RW ponds) in three Chinese cities were chosen to investigate 22 indices of sediment quality in four categories: eutrophication, heavy metal, ecotoxicity and pathogens risk. RW ponds were compared with other ponds of similar characteristics in the same cities that were replenished with SW (SW ponds). Our results show a strong impact of RW to the eutrophication and pathogenic risks, which are represented by organic matter, water content, total nitrogen, total phosphorus and phosphorus fractions, and pathogens. In particular, total phosphorus concentrations in the RW pond sediments were, on average, 50% higher than those of SW ponds. Moreover, the content of phosphorus, extracted by bicarbonate/dithionite (normally represented by BD-P) and NaOH (NaOH-P), were 2.0- and 2.83-times higher in RW ponds, respectively. For pathogens, the concentrations of norovirus and rotavirus in RW pond sediments were, on average, 0.52 and 0.30- log times those of SW ponds. The duration of RW replenishment was proved to have a marked impact on the eutrophication and pathogens risks from sediments. The continued use of RW for replenishment increases the eutrophication risk, and the pathogens risk, especially by viral pathogens, becomes greater. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Heteropoly acid catalyzed hydrolysis of glycogen to glucose

    International Nuclear Information System (INIS)

    Klein, Miri; Pulidindi, Indra Neel; Perkas, Nina; Gedanken, Aharon

    2015-01-01

    Complete conversion of glycogen to glucose is achieved by using H 3 PW 12 O 40 ·nH 2 O (HPW) and H 4 SiW 12 O 40 ·nH 2 O (HSiW) as catalysts for the hydrolysis under optimized hydrothermal conditions (mass fraction of catalyst 2.4%, 373 K and 2 h reaction time). The reusability of the catalyst (HPW) was demonstrated. In addition to carrying out the glycogen hydrolysis in an autoclave, other novel methods such as microwave irradiation and sonication have also been investigated. At higher mass fraction of the heteropoly acids (10.5%), glycogen could be completely converted to glucose under microwave irradiation. Sonication of an aqueous solution of glycogen in the presence of HPW and HSiW also yielded glucose. Thus, heteropoly acids are efficient, environmentally friendly and reusable catalysts for the conversion of glycogen to glucose. - Highlights: • Hydrothermal, microwave and sonication based methods of hydrolysis. • Heteropoly acids are green catalysts for glycogen hydrolysis. • Glycogen from cyanobacteria is demonstrated as a potential feedstock for glucose

  9. Glycogen branching enzyme (GBE1) mutation causing equine glycogen storage disease IV.

    Science.gov (United States)

    Ward, Tara L; Valberg, Stephanie J; Adelson, David L; Abbey, Colette A; Binns, Matthew M; Mickelson, James R

    2004-07-01

    Comparative biochemical and histopathological evidence suggests that a deficiency in the glycogen branching enzyme, encoded by the GBE1 gene, is responsible for a recently identified recessive fatal fetal and neonatal glycogen storage disease (GSD) in American Quarter Horses termed GSD IV. We have now derived the complete GBE1 cDNA sequences for control horses and affected foals, and identified a C to A substitution at base 102 that results in a tyrosine (Y) to stop (X) mutation in codon 34 of exon 1. All 11 affected foals were homozygous for the X34 allele, their 11 available dams and sires were heterozygous, and all 16 control horses were homozygous for the Y34 allele. The previous findings of poorly branched glycogen, abnormal polysaccharide accumulation, lack of measurable GBE1 enzyme activity and immunodetectable GBE1 protein, coupled with the present observation of abundant GBE1 mRNA in affected foals, are all consistent with the nonsense mutation in the 699 amino acid GBE1 protein. The affected foal pedigrees have a common ancestor and contain prolific stallions that are likely carriers of the recessive X34 allele. Defining the molecular basis of equine GSD IV will allow for accurate DNA testing and the ability to prevent occurrence of this devastating disease affecting American Quarter Horses and related breeds.

  10. Preactivated thiolated glycogen as mucoadhesive polymer for drug delivery.

    Science.gov (United States)

    Perrone, Mara; Lopalco, Antonio; Lopedota, Angela; Cutrignelli, Annalisa; Laquintana, Valentino; Douglas, Justin; Franco, Massimo; Liberati, Elisa; Russo, Vincenzo; Tongiani, Serena; Denora, Nunzio; Bernkop-Schnürch, Andreas

    2017-10-01

    The purpose of this study was to synthesize and characterize a novel thiolated glycogen, so-named S-preactivated thiolated glycogen, as a mucosal drug delivery systems and the assessment of its mucoadhesive properties. In this regard, glycogen-cysteine and glycogen-cysteine-2-mercaptonicotinic acid conjugates were synthesized. Glycogen was activated by an oxidative ring opening with sodium periodate resulting in reactive aldehyde groups to which cysteine was bound via reductive amination. The obtained thiolated polymer displayed 2203.09±200μmol thiol groups per gram polymer. In a second step, the thiol moieties of thiolated glycogen were protected by disulfide bond formation with the thiolated aromatic residue 2-mercaptonicotinic acid (2MNA). In vitro screening of mucoadhesive properties was performed on porcine intestinal mucosa using different methods. In particular, in terms of rheology investigations of mucus/polymer mixtures, the S-preactivated thiolated glycogen showed a 4.7-fold increase in dynamic viscosity over a time period of 5h, in comparison to mucus/Simulated Intestinal Fluid control. The S-preactivated polymer remained attached on freshly excised porcine mucosa for 45h. Analogous results were obtained with tensile studies demonstrating a 2.7-fold increase in maximum detachment force and 3.1- fold increase in total work of adhesion for the S-preactivated polymer compared to unmodified glycogen. Moreover, water-uptake studies showed an over 4h continuing weight gain for the S-preactivated polymer, whereas disintegration took place for the unmodified polymer within the first hour. Furthermore, even in the highest tested concentration of 2mg/ml the new conjugates did not show any cytotoxicity on Caco-2 cell monolayer using an MTT assay. According to these results, S-preactivated glycogen represents a promising type of mucoadhesive polymers useful for the development of various mucosal drug delivery systems. Copyright © 2017 Elsevier B.V. All rights

  11. Glycogen synthase activation by sugars in isolated hepatocytes.

    Science.gov (United States)

    Ciudad, C J; Carabaza, A; Bosch, F; Gòmez I Foix, A M; Guinovart, J J

    1988-07-01

    We have investigated the activation by sugars of glycogen synthase in relation to (i) phosphorylase a activity and (ii) changes in the intracellular concentration of glucose 6-phosphate and adenine nucleotides. All the sugars tested in this work present the common denominator of activating glycogen synthase. On the other hand, phosphorylase a activity is decreased by mannose and glucose, unchanged by galactose and xylitol, and increased by tagatose, glyceraldehyde, and fructose. Dihydroxyacetone exerts a biphasic effect on phosphorylase. These findings provide additional evidence proving that glycogen synthase can be activated regardless of the levels of phosphorylase a, clearly establishing that a nonsequential mechanism for the activation of glycogen synthase occurs in liver cells. The glycogen synthase activation state is related to the concentrations of glucose 6-phosphate and adenine nucleotides. In this respect, tagatose, glyceraldehyde, and fructose deplete ATP and increase AMP contents, whereas glucose, mannose, galactose, xylitol, and dihydroxyacetone do not alter the concentration of these nucleotides. In addition, all these sugars, except glyceraldehyde, increase the intracellular content of glucose 6-phosphate. The activation of glycogen synthase by sugars is reflected in decreases on both kinetic constants of the enzyme, M0.5 (for glucose 6-phosphate) and S0.5 (for UDP-glucose). We propose that hepatocyte glycogen synthase is activated by monosaccharides by a mechanism triggered by changes in glucose 6-phosphate and adenine nucleotide concentrations which have been described to modify glycogen synthase phosphatase activity. This mechanism represents a metabolite control of the sugar-induced activation of hepatocyte glycogen synthase.

  12. Information for stores users

    CERN Multimedia

    2006-01-01

    The Bossard catalogue is now accessible alongside the CERN Stores catalogue from the Material Request form on EDH. Users will thus be able to order Bossard equipment using the EDH Materials Request form. As a reminder, the system automatically forwards orders for standard Stores equipment to the CERN Stores and those for Bossard equipment to Bossard. In both cases the delivery time will be a maximum of 48 hours. Requests for materials will be routed for approval in accordance with the standard EDH routing procedures. Some items will remain available from the emergency desk in the event of urgent requests. These items will be visible in the Stores catalogue even if they cannot be purchased via the EDH material request form. Logistics Group FI Department

  13. Provenance Store Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Paulson, Patrick R.; Gibson, Tara D.; Schuchardt, Karen L.; Stephan, Eric G.

    2008-03-01

    Requirements for the provenance store and access API are developed. Existing RDF stores and APIs are evaluated against the requirements and performance benchmarks. The team’s conclusion is to use MySQL as a database backend, with a possible move to Oracle in the near-term future. Both Jena and Sesame’s APIs will be supported, but new code will use the Jena API

  14. Mechanisms limiting glycogen storage in muscle during prolonged insulin stimulation

    DEFF Research Database (Denmark)

    Richter, Erik; Hansen, S A; Hansen, B F

    1988-01-01

    increased muscle glycogen concentrations to maximal values 2, 3, and 3.5 times above normal fed levels in fast-twitch white, slow-twitch red, and fast-twitch red fibers, respectively. Glucose uptake decreased (mean +/- SE) from 34.9 +/- 1.2 mumol.g-1.h-1 at 0 h to 7.5 +/- 0.7 after 7 h of perfusion. During...... compared with initial values. Total muscle water concentration decreased during glycogen loading of the muscles. Mechanisms limiting glycogen storage under maximal insulin stimulation include impaired insulin-stimulated membrane transport of glucose as well as impaired intracellular glucose disposal....

  15. Hepatic glycogen synthesis in the fetal mouse: An ultrastructural, morphometric, and autoradiographic investigation of the relationship between the smooth endoplasmic reticulum and glycogen

    International Nuclear Information System (INIS)

    Breslin, J.S.

    1989-01-01

    Fetal rodent hepatocytes undergo a rapid and significant accumulation of glycogen prior to birth. The distinct association of the smooth endoplasmic reticulum (SER) with glycogen during glycogen synthesis documented in the adult hepatocyte has not been clearly demonstrated in the fetus. The experiments described in this dissertation tested the hypothesis that SER is present and functions in the synthesis of fetal hepatic glycogen. Biochemical analysis, light microscopic (LM) histochemistry and electron microscope (EM) morphometry demonstrated that fetal hepatic glycogen synthesis began on day 15, with maximum accumulation occurring between days 17-19. Glycogen accumulation began in a small population of cells. Both the number of cells containing glycogen and the quantity of glycogen per cell increased as glycogen accumulated. Smooth endoplasmic reticulum (SER) was observed on day 14 of gestation and throughout fetal hepatic glycogen synthesis, primarily as dilated ribosome-free terminal extensions of rough endoplasmic reticulum (RER), frequently associated with glycogen. SER was in close proximity to isolated particles of glycogen and at the periphery of large compact glycogen deposits. Morphometry demonstrated that the membrane surface of SER in the average fetal hepatocyte increased as glycogen accumulated through day 18 and dropped significantly as glycogen levels peaked on day 19. Parallel alterations in RER membrane surface, indicated overall increases in ER membrane surface. Autoradiography following administration of 3 H-galactose demonstrated that newly synthesized glycogen was deposited near profiles of SER at day 16 and at day 18; however, at day 18 the majority of label was uniformly distributed over glycogen remote from profiles of SER

  16. Deleterious effects of neuronal accumulation of glycogen in flies and mice

    OpenAIRE

    Duran, Jordi; Tevy, María Florencia; Garcia-Rocha, Mar; Calbó, Joaquim; Milán, Marco; Guinovart, Joan J

    2012-01-01

    Under physiological conditions, most neurons keep glycogen synthase (GS) in an inactive form and do not show detectable levels of glycogen. Nevertheless, aberrant glycogen accumulation in neurons is a hallmark of patients suffering from Lafora disease or other polyglucosan disorders. Although these diseases are associated with mutations in genes involved in glycogen metabolism, the role of glycogen accumulation remains elusive. Here, we generated mouse and fly models expressing an active form...

  17. The Nord interim store

    International Nuclear Information System (INIS)

    Leushacke, D.F.; Rittscher, D.

    1996-01-01

    In line with the decision taken in 1990 to shut down and decommission the Greifswald and Rheinsberg Nuclear Power Stations, the waste management concept of the Energiewerke Nord is based on direct and complete decommissioning of the six shut down reactor units within the next fifteen years. One key element of this concept is the construction and use of the Zwischenlager Nord (Nord Interim Store, ZLN) for holding the existing nuclear fuels and for interim and decay storage of the radioactive materials arising in decommissioning and demolition. The owner and operator of the store is Energiewerke Nord GmbH. The interim store has the functions of a processing and Energiewerke Nord GmbH. The interim store has the functions of a processing and treatment station and buffer store for the flows of residues arising. As a radioactive waste management station, it accommodates nuclear fuels, radioactive waste or residues which are not treated any further. It is used as a buffer store to allow the materials accumulating in disassembly to be stored temporarily before or after treatment in order to ensure continuous loading of the treatment plants. When operated as a processing station, the ZLN is able to handle nearly all types of radioactive waste and residues arising, except for nuclear fuels. These installations allow the treatment of radioactive residues to be separated from the demolition work both physically and in time. The possibilities of interium storage and buffer storage of untreated waste and waste packages make for high flexibility in logistics and waste management strategy. (orig.) [de

  18. Genetics Home Reference: glycogen storage disease type VI

    Science.gov (United States)

    ... or elevated levels of ketones in the blood (ketosis). Ketones are molecules produced during the breakdown of ... and may use fats for energy, resulting in ketosis. Glycogen accumulates within liver cells, causing these cells ...

  19. Genetics Home Reference: glycogen storage disease type IX

    Science.gov (United States)

    ... or elevated levels of ketones in the blood (ketosis). Ketones are molecules produced during the breakdown of ... down glycogen for glucose contributes to hypoglycemia and ketosis. Reduced energy production in muscle cells leads to ...

  20. Human skeletal muscle glycogen utilization in exhaustive exercise

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Holmberg, Hans-Christer; Schrøder, Henrik Daa

    2011-01-01

    Although glycogen is known to be heterogeneously distributed within skeletal muscle cells, there is presently little information available about the role of fibre types, utilization and resynthesis during and after exercise with respect to glycogen localization. Here, we tested the hypothesis...... to be influenced by fibre type prior to exercise, as well as carbohydrate availability during the subsequent period of recovery. These findings provide insight into the significance of fibre type-specific compartmentalization of glycogen metabolism in skeletal muscle during exercise and subsequent recovery. ....... that utilization of glycogen with different subcellular localizations during exhaustive arm and leg exercise differs and examined the influence of fibre type and carbohydrate availability on its subsequent resynthesis. When 10 elite endurance athletes (22 ± 1 years, VO2 max = 68 ± 5 ml kg-1 min-1, mean ± SD...

  1. Genetics Home Reference: glycogen storage disease type V

    Science.gov (United States)

    ... with GSDV experience mild symptoms such as poor stamina; others do not experience any symptoms. Related Information ... myophosphorylase. This enzyme is found only in muscle cells, where it breaks down glycogen into a simpler ...

  2. Impaired glycogen synthase activity and mitochondrial dysfunction in skeletal muscle

    DEFF Research Database (Denmark)

    Højlund, Kurt; Beck-Nielsen, Henning

    2006-01-01

    Insulin resistance in skeletal muscle is a major hallmark of type 2 diabetes and an early detectable abnormality in the development of this disease. The cellular mechanisms of insulin resistance include impaired insulin-mediated muscle glycogen synthesis and increased intramyocellular lipid content......, whereas impaired insulin activation of muscle glycogen synthase represents a consistent, molecular defect found in both type 2 diabetic and high-risk individuals. Despite several studies of the insulin signaling pathway believed to mediate dephosphorylation and hence activation of glycogen synthase......, the molecular mechanisms responsible for this defect remain unknown. Recently, the use of phospho-specific antibodies in human diabetic muscle has revealed hyperphosphorylation of glycogen synthase at sites not regulated by the classical insulin signaling pathway. In addition, novel approaches such as gene...

  3. Intracellular compartmentalization of skeletal muscle glycogen metabolism and insulin signalling

    DEFF Research Database (Denmark)

    Prats Gavalda, Clara; Gomez-Cabello, Alba; Vigelsø Hansen, Andreas

    2011-01-01

    The interest in skeletal muscle metabolism and insulin signalling has increased exponentially in recent years as a consequence of their role in the development of type 2 diabetes mellitus. Despite this, the exact mechanisms involved in the regulation of skeletal muscle glycogen metabolism...... and insulin signalling transduction remain elusive. We believe that one of the reasons is that the role of intracellular compartmentalization as a regulator of metabolic pathways and signalling transduction has been rather ignored. This paper briefly reviews the literature to discuss the role of intracellular...... compartmentalization in the regulation of skeletal muscle glycogen metabolism and insulin signalling. As a result, a hypothetical regulatory mechanism is proposed by which cells could direct glycogen resynthesis towards different pools of glycogen particles depending on the metabolic needs. Furthermore, we discuss...

  4. The effect of glycogen phosphorolysis on basal glutaminergic transmission.

    Science.gov (United States)

    Mozrzymas, Jerzy; Szczęsny, Tomasz; Rakus, Darek

    2011-01-14

    Astrocytic glycogen metabolism sustains neuronal activity but its impact on basal glutamatergic synaptic transmission is not clear. To address this issue, we have compared the effect of glycogen breakdown inhibition on miniature excitatory postsynaptic currents (mEPSCs) in rat hippocampal pure neuronal culture (PNC) and in astrocyte-neuronal co-cultures (ANCC). Amplitudes of mEPSC in ANCC were nearly twice as large as in PNC with no difference in current kinetics. Inhibition of glycogen phosphorylase reduced mEPSC amplitude by roughly 40% in ANCC being ineffective in PNC. Altogether, these data indicate that astrocyte-neuronal interaction enhances basal mEPSCs in ANCC mainly due to astrocytic glycogen metabolism. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Glycogen-bound polyphosphate kinase from the archaebacterium Sulfolobus acidocaldarius.

    OpenAIRE

    Skórko, R; Osipiuk, J; Stetter, K O

    1989-01-01

    Glycogen-bound polyphosphate kinase has been isolated from a crude extract of Sulfolobus acidocaldarius by isopycnic centrifugation in CsCl. Divalent cations (Mn2+ greater than Mg2+) stimulated the reaction. The enzyme does not require the presence of histones for its activity; it is inhibited strongly by phosphate and slightly by fluoride. The protein from the glycogen complex migrated in a sodium dodecyl sulfate-polyacrylamide gel as a 57-kilodalton protein band; after isoelectric focusing ...

  6. Inadequate Brain Glycogen or Sleep Increases Spreading Depression Susceptibility

    KAUST Repository

    Kilic, Kivilcim; Karatas, Hulya; Donmez-Demir, Buket; Eren-Kocak, Emine; Gursoy-Ozdemir, Yasemin; Can, Alp; Petit, Jean-Marie; Magistretti, Pierre J.; Dalkara, Turgay

    2017-01-01

    Glycogen in astrocyte endfeet contributes to maintenance of low extracellular glutamate and K+ concentrations around synapses. Sleep deprivation (SD), a common migraine trigger induces transcriptional changes in astrocytes reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches.We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD.DAB caused neuronal pannexin-1 large-pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking-down neuronal lactate transporter, MCT2 with an anti-sense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly given phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, APG-4 disclosed that DAB treatment or SD caused significant rise in extracellular K+ during whisker-stimulation, illustrating the critical role of glycogen in extracellular K+ clearance.Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lowering the CSD threshold. Therefore, conditions that limit energy supply to synapse (e.g. SD) may predispose to migraine attacks as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. This article is protected by copyright. All rights reserved.

  7. Inadequate Brain Glycogen or Sleep Increases Spreading Depression Susceptibility

    KAUST Repository

    Kilic, Kivilcim

    2017-12-16

    Glycogen in astrocyte endfeet contributes to maintenance of low extracellular glutamate and K+ concentrations around synapses. Sleep deprivation (SD), a common migraine trigger induces transcriptional changes in astrocytes reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches.We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD.DAB caused neuronal pannexin-1 large-pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking-down neuronal lactate transporter, MCT2 with an anti-sense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly given phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, APG-4 disclosed that DAB treatment or SD caused significant rise in extracellular K+ during whisker-stimulation, illustrating the critical role of glycogen in extracellular K+ clearance.Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lowering the CSD threshold. Therefore, conditions that limit energy supply to synapse (e.g. SD) may predispose to migraine attacks as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. This article is protected by copyright. All rights reserved.

  8. In vitro variation of glycogen content in three sheep nematodes.

    Science.gov (United States)

    Premvati, G; Chopra, A K

    1979-06-01

    In vitro variation of glycogen content under aerobic conditions was measured on fresh weight basis in 3 sheep nematodes inhabiting different niches; Haemonchus contortus, Oesophagostomum columbianum and Trichuris ovis. The parasites were saparated into species and then sexes and starved for varying periods of time up to 24 h in glucose-free physiological saline. The differences between females and males and among the species with respect to glycogen content and its rate of change with time are discussed.

  9. Inflammable materials stores

    International Nuclear Information System (INIS)

    Nandagopan, V.

    2017-01-01

    A new Inflammable Materials Stores has been constructed by A and SED, BARC near Gamma Field for storage of inflammable materials falling into Petroleum Class ‘A’ ‘B’ and “C” mainly comprising of oils and lubricants, Chemicals like Acetone, Petroleum Ether etc. which are regularly procured by Central Stores Unit (CSU) for issue to the various divisions of BARC. The design of the shed done by A and SED, BARC was duly got approved from Petroleum and Explosive Safety Organization (PESO) which is a mandatory requirement before commencement of the construction. The design had taken into account various safety factors which is ideally required for an inflammable materials stores

  10. Operational Qualification (OQ) Of MINTEC-Sinagama After Cobalt-60 Sources Replenishment

    International Nuclear Information System (INIS)

    Ruzalina Baharin; Hasan Sham; Ahsanulkhaliqin Abdul Wahab

    2014-01-01

    Activity on cobalt-60 sources replenishment at MINTec-Sinagama had been held in May 2014 with total strength of gamma as 440,000 Ci. Therefore, operational qualification (OQ) needs to be done in order to ensure that Sinagama plant is operating well and deliver suitable doses to the customer's products. In this work, three dose mapping exercises were carried out to establish dose distributions and dose reproducibility of plant, which are corresponded to the density of irradiator container (tote) and absorbed dose at normal operation. Dosimeters used were ceric cerous produced by SSDL, Malaysian Nuclear Agency and placed on three planes that represent three-dimensional array. They were located at certain intervals throughout the tote. This paper describes the OQ process and a bit touch on replenishment activity. (author)

  11. The optimal replenishment policy for time-varying stochastic demand under vendor managed inventory

    DEFF Research Database (Denmark)

    Govindan, Kannan

    2015-01-01

    A Vendor Managed Inventory (VMI) partnership places the responsibility on the vendor (rather than on buyers) to schedule purchase orders for inventory replenishment in the supply chain system. In this research, the supply chain network considers the Silver-Meal heuristic with an augmentation...... quantity replenishment policy between both traditional and VMI systems. We consider time-varying stochastic demand in two-echelon (one vendor, multiple retailers) supply chains. This paper seeks to find the supply chain that minimizes system cost through comparing performance between traditional and VMI...... systems. A mathematical model is developed, and total supply chain cost is used as the measure of comparison. The models are applied in both traditional and VMI supply chains based on pharmaceutical industry data, and we focus on total cost difference compared through the use of Adjusted Silver-Meal (ASM...

  12. Information for Stores users

    CERN Multimedia

    FI Department

    2008-01-01

    The DISTRELEC catalogue (IT) is now available in EDH in addition to the CERN Stores catalogue and the catalogues of existing suppliers. Using an EDH materials request form, users can now order DISTRELEC equipment from amongst the following product groups: peripherals, multimedia, PC components, data media, communication and data cables and adapters. Non-authorised materials will be clearly indicated. As a reminder, the system automatically manages the distribution of standard Stores equipment and punch out equipment ordered on the same request form. In both cases, delivery will take a maximum of 48 hours. The approval of the EDH document will follow the usual EDH routing procedures. Logistics Group FI Department

  13. Preliminary Experimental Results on the Technique of Artificial River Replenishment to Mitigate Sediment Loss Downstream Dams

    Science.gov (United States)

    Franca, M. J.; Battisacco, E.; Schleiss, A. J.

    2014-12-01

    The transport of sediments by water throughout the river basins, from the steep slopes of the upstream regions to the sea level, is recognizable important to keep the natural conditions of rivers with a role on their ecology processes. Over the last decades, a reduction on the supply of sand and gravel has been observed downstream dams existing in several alpine rivers. Many studies highlight that the presence of a dam strongly modifies the river behavior in the downstream reach, in terms of morphology and hydrodynamics, with consequences on local ecology. Sediment deficit, bed armoring, river incision and bank instability are the main effects which affect negatively the aquatic habitats and the water quality. One of the proposed techniques to solve the problem of sediment deficit downstream dams, already adopted in few Japanese and German rivers although on an unsatisfactory fashion, is the artificial replenishment of these. Generally, it was verified that the erosion of the replenishments was not satisfactory and the transport rate was not enough to move the sediments to sufficient downstream distances. In order to improve and to provide an engineering answer to make this technique more applicable, a series of laboratory tests are ran as preparatory study to understand the hydrodynamics of the river flow when the replenishment technique is applied. Erodible volumes, with different lengths and submergence conditions, reproducing sediment replenishments volumes, are positioned along a channel bank. Different geometrical combinations of erodible sediment volumes are tested as well on the experimental flume. The first results of the experimental research, concerning erosion time evolution, the influence of discharge and the distance travelled by the eroded sediments, will be presented and discussed.

  14. Optimal Lot Sizing with Scrap and Random Breakdown Occurring in Backorder Replenishing Period

    OpenAIRE

    Ting, Chia-Kuan; Chiu, Yuan-Shyi; Chan, Chu-Chai

    2011-01-01

    This paper is concerned with determination of optimal lot size for an economic production quantity model with scrap and random breakdown occurring in backorder replenishing period. In most real-life manufacturing systems, generation of defective items and random breakdown of production equipment are inevitable. To deal with the stochastic machine failures, production planners practically calculate the mean time between failures (MTBF) and establish the robust plan accordingly, in terms of opt...

  15. The role of the geothermal gradient in the emplacement and replenishment of ground ice on Mars

    Science.gov (United States)

    Clifford, Stephen M.

    1993-01-01

    Knowledge of the mechanisms by which ground ice is emplaced, removed, and potentially replenished, are critical to understanding the climatic and hydrologic behavior of water on Mars, as well as the morphologic evolution of its surface. Because of the strong temperature dependence of the saturated vapor pressure of H2O, the atmospheric emplacement or replenishment of ground ice is prohibited below the depth at which crustal temperatures begin to monotonically increase due to geothermal heating. In contrast, the emplacement and replenishment of ground ice from reservoirs of H2O residing deep within the crust can occur by at least three different thermally-driven processes, involving all three phases of water. In this regard, Clifford has discussed how the presence of a geothermal gradient as small as 15 K/km can give rise to a corresponding vapor pressure gradient sufficient to drive the vertical transport of 1 km of water from a reservoir of ground water at depth to the base of the cryosphere every 10(exp 6) - 10(exp 7) years. This abstract expands on this earlier treatment by considering the influence of thermal gradients on the transport of H2O at temperatures below the freezing point.

  16. Genomic and in Situ Analyses Reveal the Micropruina spp. as Abundant Fermentative Glycogen Accumulating Organisms in Enhanced Biological Phosphorus Removal Systems

    Directory of Open Access Journals (Sweden)

    Simon J. McIlroy

    2018-05-01

    Full Text Available Enhanced biological phosphorus removal (EBPR involves the cycling of biomass through carbon-rich (feast and carbon-deficient (famine conditions, promoting the activity of polyphosphate accumulating organisms (PAOs. However, several alternate metabolic strategies, without polyphosphate storage, are possessed by other organisms, which can compete with the PAO for carbon at the potential expense of EBPR efficiency. The most studied are the glycogen accumulating organisms (GAOs, which utilize aerobically stored glycogen to energize anaerobic substrate uptake and storage. In full-scale systems the Micropruina spp. are among the most abundant of the proposed GAO, yet little is known about their ecophysiology. In the current study, genomic and metabolomic studies were performed on Micropruina glycogenica str. Lg2T and compared to the in situ physiology of members of the genus in EBPR plants using state-of-the-art single cell techniques. The Micropruina spp. were observed to take up carbon, including sugars and amino acids, under anaerobic conditions, which were partly fermented to lactic acid, acetate, propionate, and ethanol, and partly stored as glycogen for potential aerobic use. Fermentation was not directly demonstrated for the abundant members of the genus in situ, but was strongly supported by the confirmation of anaerobic uptake of carbon and glycogen storage in the absence of detectable polyhydroxyalkanoates or polyphosphate reserves. This physiology is markedly different from the classical GAO model. The amount of carbon stored by fermentative organisms has potentially important implications for phosphorus removal – as they compete for substrates with the Tetrasphaera PAO and stored carbon is not made available to the “Candidatus Accumulibacter” PAO under anaerobic conditions. This study shows that the current models of the competition between PAO and GAO are too simplistic and may need to be revised to take into account the impact of

  17. Shaktismen - hinduismens store gudindetradition

    DEFF Research Database (Denmark)

    Olesen, Bjarne Wernicke

    2008-01-01

    Artiklen giver en introduktion til shaktismen - hinduismens store gudindetradition. Den ser på de vigtigste gudinder, begreber, traditioner og forestillinger, ligesom den giver et vue over forskningssituationen. Shaktismens opståen i sin klassiske form, dens hovedretninger, virkelighedsforståelse...

  18. Information for stores users

    CERN Multimedia

    FI Department

    2008-01-01

    From the beginning of March onwards, the LYRECO (stationery) catalogue will be accessible from the Material Request form on EDH in the same way as the CERN Stores catalogue and the existing individual supplier catalogues. Items will be delivered within a maximum of 48 hours. Logistics Group FI Department

  19. Store Security: Reducing Shoplifting.

    Science.gov (United States)

    Minsel, Robert; Garman, Jerry

    The major purpose of the course outline presented in the document is the reduction of stealing in retail stores. The teaching outline is formatted by juxtaposing the content outline of each substantive area next to relevant activities and methods. Some of the topics covered are psychology of shoplifting, tools used by shoplifters, Ohio's law on…

  20. Homogenization versus homogenization-free method to measure muscle glycogen fractions.

    Science.gov (United States)

    Mojibi, N; Rasouli, M

    2016-12-01

    The glycogen is extracted from animal tissues with or without homogenization using cold perchloric acid. Three methods were compared for determination of glycogen in rat muscle at different physiological states. Two groups of five rats were kept at rest or 45 minutes muscular activity. The glycogen fractions were extracted and measured by using three methods. The data of homogenization method shows that total glycogen decreased following 45 min physical activity and the change occurred entirely in acid soluble glycogen (ASG), while AIG did not change significantly. Similar results were obtained by using "total-glycogen-fractionation methods". The findings of "homogenization-free method" indicate that the acid insoluble fraction (AIG) was the main portion of muscle glycogen and the majority of changes occurred in AIG fraction. The results of "homogenization method" are identical with "total glycogen fractionation", but differ with "homogenization-free" protocol. The ASG fraction is the major portion of muscle glycogen and is more metabolically active form.

  1. Neurons have an active glycogen metabolism that contributes to tolerance to hypoxia

    Science.gov (United States)

    Saez, Isabel; Duran, Jordi; Sinadinos, Christopher; Beltran, Antoni; Yanes, Oscar; Tevy, María F; Martínez-Pons, Carlos; Milán, Marco; Guinovart, Joan J

    2014-01-01

    Glycogen is present in the brain, where it has been found mainly in glial cells but not in neurons. Therefore, all physiologic roles of brain glycogen have been attributed exclusively to astrocytic glycogen. Working with primary cultured neurons, as well as with genetically modified mice and flies, here we report that—against general belief—neurons contain a low but measurable amount of glycogen. Moreover, we also show that these cells express the brain isoform of glycogen phosphorylase, allowing glycogen to be fully metabolized. Most importantly, we show an active neuronal glycogen metabolism that protects cultured neurons from hypoxia-induced death and flies from hypoxia-induced stupor. Our findings change the current view of the role of glycogen in the brain and reveal that endogenous neuronal glycogen metabolism participates in the neuronal tolerance to hypoxic stress. PMID:24569689

  2. Glucose uptake and transport in contracting, perfused rat muscle with different pre-contraction glycogen concentrations

    DEFF Research Database (Denmark)

    Hespel, P; Richter, Erik

    1990-01-01

    1. Glucose uptake and transport, muscle glycogen, free glucose and glucose-6-phosphate concentrations were studied in perfused resting and contracting rat skeletal muscle with different pre-contraction glycogen concentrations. Rats were pre-conditioned by a combination of swimming exercise and diet......, resulting in either low (glycogen-depleted rats), normal (control rats) or high (supercompensated rats) muscle glycogen concentrations at the time their hindlimbs were perfused. 2. Compared with control rats, pre-contraction muscle glycogen concentration was approximately 40% lower in glycogen-depleted rats......, whereas it was 40% higher in supercompensated rats. Muscle glycogen break-down correlated positively (r = 0.76; P less than 0.001) with pre-contraction muscle glycogen concentration. 3. Glucose uptake during contractions was approximately 50% higher in glycogen-depleted hindquarters than in control...

  3. Neurons have an active glycogen metabolism that contributes to tolerance to hypoxia.

    Science.gov (United States)

    Saez, Isabel; Duran, Jordi; Sinadinos, Christopher; Beltran, Antoni; Yanes, Oscar; Tevy, María F; Martínez-Pons, Carlos; Milán, Marco; Guinovart, Joan J

    2014-06-01

    Glycogen is present in the brain, where it has been found mainly in glial cells but not in neurons. Therefore, all physiologic roles of brain glycogen have been attributed exclusively to astrocytic glycogen. Working with primary cultured neurons, as well as with genetically modified mice and flies, here we report that-against general belief-neurons contain a low but measurable amount of glycogen. Moreover, we also show that these cells express the brain isoform of glycogen phosphorylase, allowing glycogen to be fully metabolized. Most importantly, we show an active neuronal glycogen metabolism that protects cultured neurons from hypoxia-induced death and flies from hypoxia-induced stupor. Our findings change the current view of the role of glycogen in the brain and reveal that endogenous neuronal glycogen metabolism participates in the neuronal tolerance to hypoxic stress.

  4. Acid hydrolysis and molecular density of phytoglycogen and liver glycogen helps understand the bonding in glycogen α (composite particles.

    Directory of Open Access Journals (Sweden)

    Prudence O Powell

    Full Text Available Phytoglycogen (from certain mutant plants and animal glycogen are highly branched glucose polymers with similarities in structural features and molecular size range. Both appear to form composite α particles from smaller β particles. The molecular size distribution of liver glycogen is bimodal, with distinct α and β components, while that of phytoglycogen is monomodal. This study aims to enhance our understanding of the nature of the link between liver-glycogen β particles resulting in the formation of large α particles. It examines the time evolution of the size distribution of these molecules during acid hydrolysis, and the size dependence of the molecular density of both glucans. The monomodal distribution of phytoglycogen decreases uniformly in time with hydrolysis, while with glycogen, the large particles degrade significantly more quickly. The size dependence of the molecular density shows qualitatively different shapes for these two types of molecules. The data, combined with a quantitative model for the evolution of the distribution during degradation, suggest that the bonding between β into α particles is different between phytoglycogen and liver glycogen, with the formation of a glycosidic linkage for phytoglycogen and a covalent or strong non-covalent linkage, most probably involving a protein, for glycogen as most likely. This finding is of importance for diabetes, where α-particle structure is impaired.

  5. Acid Hydrolysis and Molecular Density of Phytoglycogen and Liver Glycogen Helps Understand the Bonding in Glycogen α (Composite) Particles

    Science.gov (United States)

    Powell, Prudence O.; Sullivan, Mitchell A.; Sheehy, Joshua J.; Schulz, Benjamin L.; Warren, Frederick J.; Gilbert, Robert G.

    2015-01-01

    Phytoglycogen (from certain mutant plants) and animal glycogen are highly branched glucose polymers with similarities in structural features and molecular size range. Both appear to form composite α particles from smaller β particles. The molecular size distribution of liver glycogen is bimodal, with distinct α and β components, while that of phytoglycogen is monomodal. This study aims to enhance our understanding of the nature of the link between liver-glycogen β particles resulting in the formation of large α particles. It examines the time evolution of the size distribution of these molecules during acid hydrolysis, and the size dependence of the molecular density of both glucans. The monomodal distribution of phytoglycogen decreases uniformly in time with hydrolysis, while with glycogen, the large particles degrade significantly more quickly. The size dependence of the molecular density shows qualitatively different shapes for these two types of molecules. The data, combined with a quantitative model for the evolution of the distribution during degradation, suggest that the bonding between β into α particles is different between phytoglycogen and liver glycogen, with the formation of a glycosidic linkage for phytoglycogen and a covalent or strong non-covalent linkage, most probably involving a protein, for glycogen as most likely. This finding is of importance for diabetes, where α-particle structure is impaired. PMID:25799321

  6. STORE IN STORE FRANCHISING STRATEGY: THE TREND IN FRANCHISING NEGOTIATION

    OpenAIRE

    Rosado-Serrano, Alexander; Universidad de Puerto Rico

    2016-01-01

    The literature on franchising has traditionally focused on the effects and transformation it has promoted in the service sector, retailing, restaurants, hotels and other service-related industries. Store within a store research has been focused on the perspective of the manufacturer entering department stores. To date, little research has been carried out for the store in store strategy from the franchising perspective. This paper explores why big box retailers such as Walmart are adopting th...

  7. Glycogen storage disease type Ia: linkage of glucose, glycogen, lactic acid, triglyceride, and uric acid metabolism.

    Science.gov (United States)

    Sever, Sakine; Weinstein, David A; Wolfsdorf, Joseph I; Gedik, Reyhan; Schaefer, Ernst J

    2012-01-01

    A female presented in infancy with hypotonia, undetectable serum glucose, lactic acidosis, and triglycerides >5000 mg/dL. The diagnosis of type 1A glycogen storage disease was made via the result of a liver biopsy, which showed increased glycogen and absent glucose-6-phosphatase enzyme activity. The patient was treated with dextrose administered orally, which was replaced by frequent feedings of cornstarch, which resulted in an improvement of her metabolic parameters. At age 18 years of age, she had marked hypertriglyceridemia (3860 mg/dL) and eruptive xanthomas and was treated with fenofibrate, atorvastatin, and fish oil. At age 29 years she was noted to have multiple liver adenomas, severe anemia, and hyperuricemia. Aggressive cornstarch therapy was commenced with a goal of maintaining her blood glucose levels >75 mg/dL and lactate levels triglycerides 179, high-density lipoprotein cholesterol 32, and calculated low-density lipoprotein cholesterol 154. Her weight was stable with a body mass index of 24.8 kg/m(2). Her liver adenomas had decreased in size, and her anemia and hyperuricemia had improved. She was homozygous for the R83C missense mutation in G6PC. Our data indicate that optimized metabolic control to maintain blood glucose levels >75 mg/dL is critical in the management of this disease. Copyright © 2012. Published by Elsevier Inc.

  8. Glycogen metabolism in radiation induced hepatocellular carcinoma in Swiss albino mice

    International Nuclear Information System (INIS)

    Gupta, N.K.; Kumar, Ashok

    1988-01-01

    Glycogen content and the activities of phosphorylase, glycogen sythetase (GS), glucose 6-phosphatase (G6Pase), phosphohexose isomerase (PHI), glucose 6-phosphodehydrogenase were biochemically determined in the heparocellular carcinoma induced in swiss albino mice following radiocalcium internal irradiation. The content glycogen and the activities of phosphorylase, glycogen synthetase, G6Pase, PHI, GPT and GOT are considerably reduced in the hepatocellular carcinoma compared to that in control liver. However, the activity of G6PDH shows an increased activity. Results indicate that the decreas ed glycogen content in the hepatocellular carcinoma is due to the reduced glycogen synthetase activity and utilization of glucose by HMP pathway. (author). 2 tabs., 24 refs

  9. Estradiol stimulates glycogen synthesis whereas progesterone promotes glycogen catabolism in the uterus of the American mink (Neovison vison).

    Science.gov (United States)

    Bowman, Kole; Rose, Jack

    2017-01-01

    Glycogen synthesis by mink uterine glandular and luminal epithelia (GE and LE) is stimulated by estradiol (E 2 ) during estrus. Subsequently, the glycogen deposits are mobilized to near completion to meet the energy requirements of pre-embryonic development and implantation by as yet undetermined mechanisms. We hypothesized that progesterone (P 4 ) was responsible for catabolism of uterine glycogen reserves as one of its actions to ensure reproductive success. Mink were treated with E 2 , P 4 or vehicle (controls) for 3 days and uteri collected 24 h (E 2 , P 4 and vehicle) and 96 h (E 2 ) later. To evaluate E 2 priming, mink were treated with E 2 for 3 days, then P 4 for an additional 3 days (E 2 →P 4 ) and uteri collected 24 h later. Percent glycogen content of uterine epithelia was greater at E 2 + 96 h (GE = 5.71 ± 0.55; LE = 11.54 ± 2.32) than E 2 +24 h (GE = 3.63 ± 0.71; LE = 2.82 ± 1.03), and both were higher than controls (GE = 0.27 ± 0.15; LE = 0.54 ± 0.30; P glycogen content (GE = 0.61 ± 0.16; LE = 0.51 ± 0.13), to levels not different from controls, while concomitantly increasing catabolic enzyme (glycogen phosphorylase m and glucose-6-phosphatase) gene expression and amount of phospho-glycogen synthase protein (inactive) in uterine homogenates. Interestingly, E 2 →P 4 increased glycogen synthase 1 messenger RNA (mRNA) and hexokinase 1mRNA and protein. Our findings suggest to us that while E 2 promotes glycogen accumulation by the mink uterus during estrus and pregnancy, it is P 4 that induces uterine glycogen catabolism, releasing the glucose that is essential to support pre-embryonic survival and implantation. © 2016 Japanese Society of Animal Science.

  10. Establishment of vesicular-arbuscular mycorrhizal fungi and other microorganisms on a beach replenishment site in Florida.

    Science.gov (United States)

    Sylvia, D M; Will, M E

    1988-02-01

    Beach replenishment is a widely used method of controlling coastal erosion. To reduce erosional losses from wind, beach grasses are often planted on the replenishment sands. However, there is little information on the microbial populations in this material that may affect plant establishment and growth. The objectives of this research were to document changes in the populations of vesicular-arbuscular mycorrhizal (VAM) fungi and other soil microorganisms in replenishment materials and to determine whether roots of transplanted beach grasses become colonized by beneficial microbes. The study was conducted over a 2-year period on a replenishment project in northeastern Florida. Three sampling locations were established at 1-km intervals along the beach. Each location consisted of three plots: an established dune, replenishment sand planted with Uniola paniculata and Panicum sp., and replenishment sand left unplanted. Fungal and bacterial populations increased rapidly in the rhizosphere of beach grasses in the planted plots. However, no bacteria were recovered that could fix significant amounts of N(2). The VAM fungi established slowly on the transplanted grasses. Even after two growing seasons, levels of root colonization and sporulation were significantly below those found in the established dune. There was a shift in the dominant VAM fungi found in the planted zone with respect to those in the established dunes. The most abundant species recovered from the established dunes were Glomus deserticola, followed by Acaulospora scrobiculata and Scutellospora weresubiae. The VAM fungi that colonized the planted zone most rapidly were Glomus globiferum, followed by G. deserticola and Glomus aggregatum.

  11. Fuel element store

    International Nuclear Information System (INIS)

    Wieser, R.

    1987-01-01

    The spherical fuel elements are stored dry in cans. The cans themselves are stacked in parallel storage shafts, which are combined into a rectangular storage space. The storage space is made earthquake-proof by surrounding it with concrete. It consists of a ceiling assembled from several steel parts, which is connected to the floor by support elements. A cooling air ventilation station supplies the individual storage shaft and therefore the cans with cooling air via incoming and outgoing pipes. (DG) [de

  12. Air corrosion in storing

    International Nuclear Information System (INIS)

    Mazaudier, F.; Feron, D.; Baklouti, M.; Midoux, N.

    2001-01-01

    The air corrosiveness of a radioactive waste package has been estimated in a store inside which the environmental conditions are supposed to be rather close to the outside ones. It is expressed according to the ISO 9223 standard, from the humidification value and the amounts of sulfur dioxide and chlorine ions. A computer code has been perfected too; the thermal behaviour of the package can then been determined. (O.M.)

  13. Store and forward teledermatology

    Directory of Open Access Journals (Sweden)

    Kanthraj Garehatty

    2007-01-01

    Full Text Available Store and forward and real time or videoconferences are the two types of teledermatology services practiced. Dermatology and radio-diagnosis are visual specialties suited for store-and-forward teledermatology (SAFT. Advances in information technology, electronic instruments and biotechnology have revolutionized and brought changes in SAFT. Cellular phone, digital camera, personal digital assistants, Wi-Fi, Wi-Max and computer- aided-design software are incorporated to deliver the quality health care to remote geographic regions. Complete SAFT care equivalent to face-to-face consultation (Gold standard is essential. Health care providers in rural areas are the ′eyes′ for the consultants. Consultants to guide them should have a rapid periodic audit of visual parameters and dimensions of lesions. Given this background, this article reviews advances in 1 capture, store and transfer of images. 2 Computer Aided measurements of generalized and localized lesions and 3 the integration model to meet all the above two requirements in a centralized location. This process enables diagnosis, management, periodic assessment and complete follow-up care to achieve patient and physician satisfaction. Preservation of privacy and confidentiality of digital images is important. Uniform rules and regulations are required. Indian space research organization (ISRO, Government of India has demonstrated telemedicine pilot projects utilizing the satellite communication and mobile telemedicine units to be useful in meeting the health care needs of remote and rural India. we have to join hands with them to meet dermatology problems in rural areas.

  14. A functional glycogen biosynthesis pathway in Lactobacillus acidophilus: expression and analysis of the glg operon

    Science.gov (United States)

    Goh, Yong Jun; Klaenhammer, Todd R

    2013-01-01

    Glycogen metabolism contributes to energy storage and various physiological functions in some prokaryotes, including colonization persistence. A role for glycogen metabolism is proposed on the survival and fitness of Lactobacillus acidophilus, a probiotic microbe, in the human gastrointestinal environment. L. acidophilus NCFM possesses a glycogen metabolism (glg) operon consisting of glgBCDAP-amy-pgm genes. Expression of the glg operon and glycogen accumulation were carbon source- and growth phase-dependent, and were repressed by glucose. The highest intracellular glycogen content was observed in early log-phase cells grown on trehalose, which was followed by a drastic decrease of glycogen content prior to entering stationary phase. In raffinose-grown cells, however, glycogen accumulation gradually declined following early log phase and was maintained at stable levels throughout stationary phase. Raffinose also induced an overall higher temporal glg expression throughout growth compared with trehalose. Isogenic ΔglgA (glycogen synthase) and ΔglgB (glycogen-branching enzyme) mutants are glycogen-deficient and exhibited growth defects on raffinose. The latter observation suggests a reciprocal relationship between glycogen synthesis and raffinose metabolism. Deletion of glgB or glgP (glycogen phosphorylase) resulted in defective growth and increased bile sensitivity. The data indicate that glycogen metabolism is involved in growth maintenance, bile tolerance and complex carbohydrate utilization in L. acidophilus. PMID:23879596

  15. Characterization of the growth and degradation of glycogen in the liver

    International Nuclear Information System (INIS)

    Youn, J.; Bergman, R.

    1986-01-01

    The patterns of the growth and degradation of hepatic glycogen were studied using a computer model. The database was that of Devos and Hers on the distribution of label in glycogen from [1- 14 C] galactose injected at different times after the start of refeeding 40 h fasted mice. The data was simulated to examine the following hypotheses (H): Glycogen Synthesis H.S1: all glycogen molecules grow simultaneously. H.S2: at each moment of synthesis only a fixed number of molecules grow. H.S3: the number of growing molecules increases linearly with respect to time. H.S4: increase in the number of growing molecules is accelerated as glycogen is synthesized. Glycogen Degradation H.D1: glycogen molecules to be attacked by degrading enzymes are randomly chosen. H.D2: glycogen molecules are degraded sequentially in the reverse order of synthesis. H.D3: glycogen molecules have different probabilities of degradation depending upon the time of synthesis. The growth and degradation according to hypotheses S4 and D3, respectively, could best account for the data. The modelling study predicts that, at the beginning of refeeding, only a small number of molecules grow. But, as glycogen is synthesized, the rate of seeding of new glycogen molecules increases with time, causing a nonlinear proliferation of the number of growing molecules. During degradation glycogen molecules synthesized later have a greater chance to be degraded first, a characteristic which may be explained by the rosette structure of liver glycogen

  16. Abnormal metabolism of glycogen phosphate as a cause for Lafora disease.

    Science.gov (United States)

    Tagliabracci, Vincent S; Girard, Jean Marie; Segvich, Dyann; Meyer, Catalina; Turnbull, Julie; Zhao, Xiaochu; Minassian, Berge A; Depaoli-Roach, Anna A; Roach, Peter J

    2008-12-05

    Lafora disease is a progressive myoclonus epilepsy with onset in the teenage years followed by neurodegeneration and death within 10 years. A characteristic is the widespread formation of poorly branched, insoluble glycogen-like polymers (polyglucosan) known as Lafora bodies, which accumulate in neurons, muscle, liver, and other tissues. Approximately half of the cases of Lafora disease result from mutations in the EPM2A gene, which encodes laforin, a member of the dual specificity protein phosphatase family that is able to release the small amount of covalent phosphate normally present in glycogen. In studies of Epm2a(-/-) mice that lack laforin, we observed a progressive change in the properties and structure of glycogen that paralleled the formation of Lafora bodies. At three months, glycogen metabolism remained essentially normal, even though the phosphorylation of glycogen has increased 4-fold and causes altered physical properties of the polysaccharide. By 9 months, the glycogen has overaccumulated by 3-fold, has become somewhat more phosphorylated, but, more notably, is now poorly branched, is insoluble in water, and has acquired an abnormal morphology visible by electron microscopy. These glycogen molecules have a tendency to aggregate and can be recovered in the pellet after low speed centrifugation of tissue extracts. The aggregation requires the phosphorylation of glycogen. The aggregrated glycogen sequesters glycogen synthase but not other glycogen metabolizing enzymes. We propose that laforin functions to suppress excessive glycogen phosphorylation and is an essential component of the metabolism of normally structured glycogen.

  17. Somatomedin-C stimulates glycogen synthesis in fetal rat hepatocytes

    International Nuclear Information System (INIS)

    Freemark, M.; D'Ercole, A.J.; Handwerger, S.

    1985-01-01

    The effects of somatomedin-C/insulin-like growth factor I (Sm-C) on glycogen metabolism in cultured hepatocytes from 20-day-old rat fetuses have been examined and compared with the effects of insulin. Sm-C (25-375 ng/ml; 3.25-50 nM) stimulated dose-dependent increases in [ 14 C]glucose incorporation into glycogen (14.4-72.9% and total cell glycogen content (10.6-34.3%. Maximal stimulation of glycogen synthesis by Sm-C occurred at 2-4 h of incubation. Insulin (10 nM to 10 microM) also stimulated [ 14 C]glucose incorporation but its potency was only 1/20th that of Sm-C. The time course of stimulation of glucose incorporation by insulin was identical to that of Sm-C, the dose-response curves of the two hormones were parallel, and the maximal effects of insulin were not enhanced by simultaneous exposure of cells to Sm-C. These findings suggest that Sm-C and insulin stimulate glycogenesis in fetal liver through similar or identical mechanisms. Since the potency of Sm-C was 20 times greater than that of insulin, the glycogenic action of insulin in fetal liver may be mediated through binding to a hepatic receptor which also binds Sm-C. In addition to having mitogenic effects on fetal tissues, Sm-C may have direct anabolic effects on fetal carbohydrate metabolism

  18. Adenosine diphosphate sugar pyrophosphatase prevents glycogen biosynthesis in Escherichia coli

    Science.gov (United States)

    Moreno-Bruna, Beatriz; Baroja-Fernández, Edurne; Muñoz, Francisco José; Bastarrica-Berasategui, Ainara; Zandueta-Criado, Aitor; Rodríguez-López, Milagros; Lasa, Iñigo; Akazawa, Takashi; Pozueta-Romero, Javier

    2001-01-01

    An adenosine diphosphate sugar pyrophosphatase (ASPPase, EC 3.6.1.21) has been characterized by using Escherichia coli. This enzyme, whose activities in the cell are inversely correlated with the intracellular glycogen content and the glucose concentration in the culture medium, hydrolyzes ADP-glucose, the precursor molecule of glycogen biosynthesis. ASPPase was purified to apparent homogeneity (over 3,000-fold), and sequence analyses revealed that it is a member of the ubiquitously distributed group of nucleotide pyrophosphatases designated as “nudix” hydrolases. Insertional mutagenesis experiments leading to the inactivation of the ASPPase encoding gene, aspP, produced cells with marginally low enzymatic activities and higher glycogen content than wild-type bacteria. aspP was cloned into an expression vector and introduced into E. coli. Transformed cells were shown to contain a dramatically reduced amount of glycogen, as compared with the untransformed bacteria. No pleiotropic changes in the bacterial growth occurred in both the aspP-overexpressing and aspP-deficient strains. The overall results pinpoint the reaction catalyzed by ASPPase as a potential step of regulating glycogen biosynthesis in E. coli. PMID:11416161

  19. Mechanisms limiting glycogen storage in muscle during prolonged insulin stimulation

    International Nuclear Information System (INIS)

    Richter, E.A.; Hansen, S.A.; Hansen, B.F.

    1988-01-01

    The extent to which muscle glycogen concentrations can be increased during exposure to maximal insulin concentrations and abundant glucose was investigated in the isolated perfused rat hindquarter preparation. Perfusion for 7 h in the presence of 20,000 μU/ml insulin and 11-13 mM glucose increased muscle glycogen concentrations to maximal values 2, 3, and 3.5 times above normal fed levels in fast-twitch white, slow-twitch red, and fast-twitch red fibers, respectively. Glucose uptake decreased from 34.9 μmol·g -1 ·h -1 at 0 h to 7.5 after 7 h of perfusion. During the perfusion muscle glycogen synthase activity decreased and free intracellular glucose and glucose 6-phosphate increased indicating that glucose disposal was impaired. However, glucose transport as measured by the uptake of 3-O-[ 14 C]methyl-D-glucose was also markedly decreased after 5 and 7 h of perfusion compared with initial values. Total muscle water concentration decreased during glycogen loading of the muscles. Mechanisms limiting glycogen storage under maximal insulin stimulation include impaired insulin-stimulated membrane transport of glucose as well as impaired intracellular glucose disposal

  20. A new non-degradative method to purify glycogen.

    Science.gov (United States)

    Tan, Xinle; Sullivan, Mitchell A; Gao, Fei; Li, Shihan; Schulz, Benjamin L; Gilbert, Robert G

    2016-08-20

    Liver glycogen, a complex branched glucose polymer containing a small amount of protein, is important for maintaining glucose homeostasis (blood-sugar control) in humans. It has recently been found that glycogen molecular structure is impaired in diabetes. Isolating the carbohydrate polymer and any intrinsically-attached protein(s) is an essential prerequisite for studying this structural impairment. This requires an effective, non-degradative and efficient purification method to exclude the many other proteins present in liver. Proteins and glycogen have different ranges of molecular sizes. Despite the plethora of proteins that might still be present in significant abundance after other isolation techniques, SEC (size exclusion chromatography, also known as GPC), which separates by molecular size, should separate those extraneous to glycogen from glycogen with any intrinsically associated protein(s). A novel purification method is developed for this, based on preparative SEC following sucrose gradient centrifugation. Proteomics is used to show that the new method compares favourably with current methods in the literature. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Tissue glycogen and blood glucose in irradiated rats. I

    International Nuclear Information System (INIS)

    Ahlersova, E.; Ahlers, I.; Paulikova, E.; Praslicka, M.

    1980-01-01

    Fed and starved (overnight) male rats of the Wistar strain were exposed to whole-body irradiation with 14.35 Gy (1500 R) of X-rays. After irradiation and sham-irradiation all animals were starved until examination performed 1, 6, 24, 48 and 72 h after treatment. The concentration of glucose in the blood and the concentration of glycogen in the liver, heart, skeletal muscle, brown and white adipose tissue were determined. The concentrations of blood glucose and liver glycogen were found to increase between 1 and 6 h after irradiation of the starved animals. The most pronounced increase in glycogen concentration in the liver and heart muscle was observed 24 and 48 h after irradiation. A similar increase in the concentration of blood glucose was found between 48 and 72 h after irradiation. The fed and starved irradiated rats reacted differently, particularly between 48 and 72 h; the liver glycogen concentration decreased in the fed animals and remained elevated in the starved ones. Very high values of terminal glycemia were observed in both groups. The accumulation of glycogen in the heart muscle indicates that this organ is sensitive to ionizing radiation. (author)

  2. Tissue glycogen and blood glucose in irradiated rats. II

    International Nuclear Information System (INIS)

    Ahlersova, E.; Ahlers, I.; Praslicka, M.

    1980-01-01

    Male rats of the Wistar strain were continuously irradiated with 0.57 Gy (60 R) of gamma rays from a 60 Co source. Irradiation lasted from 1 to 50 days in an experimental field where also control animals shielded from radiation were placed. After a 16 h starvation, the concentration of glucose in the blood and of glycogen in the liver and the heart was determined 1, 3, 7, 14, 21, 25, 32, 39 and 50 days after the beginning of irradiation. The concentration of blood glucose in irradiated rats did not practically differ from that of control animals during the whole period of investigation. The concentration of liver glycogen in irradiated animals was higher than that in the controls during all time intervals, except for day 1. The values of glycogen in the heart muscle were approximately identical in the irradiated and control rats, except for day 21 when they sharply increased in the irradiated animals. In addition to the investigation of blood glucose and tissue glycogen during continuous irradiation, these parameters were studied immediately, and 1, 6 and 12 months after continuous irradiation with a daily exposure of 0.57 Gy (60 R) up to a total exposure of 14.35 Gy (1500 R) of gamma rays. Considerably higher values of liver glycogen were detected in the irradiated rats immediately, and 1 and 6 months after the end of irradiation. (author)

  3. Glycogen availability and skeletal muscle adaptations with endurance and resistance exercise

    NARCIS (Netherlands)

    Knuiman, Pim; Hopman, Maria T.E.; Mensink, Marco

    2015-01-01

    It is well established that glycogen depletion affects endurance exercise performance negatively. Moreover, numerous studies have demonstrated that post-exercise carbohydrate ingestion improves exercise recovery by increasing glycogen resynthesis. However, recent research into the effects of

  4. Mountain-bike racing – the influence of prior glycogen- reducing ...

    African Journals Online (AJOL)

    bout of glycogen-reducing exercise on the general stress and immune response to ..... interaction effect of glutamine supplementation and glycogen reduction on the .... Hammarqvist F, Ejesson B, Wernerman J. Stress hormones initiate pro-.

  5. Structural mechanism of laforin function in glycogen dephosphorylation and lafora disease.

    Science.gov (United States)

    Raththagala, Madushi; Brewer, M Kathryn; Parker, Matthew W; Sherwood, Amanda R; Wong, Brian K; Hsu, Simon; Bridges, Travis M; Paasch, Bradley C; Hellman, Lance M; Husodo, Satrio; Meekins, David A; Taylor, Adam O; Turner, Benjamin D; Auger, Kyle D; Dukhande, Vikas V; Chakravarthy, Srinivas; Sanz, Pascual; Woods, Virgil L; Li, Sheng; Vander Kooi, Craig W; Gentry, Matthew S

    2015-01-22

    Glycogen is the major mammalian glucose storage cache and is critical for energy homeostasis. Glycogen synthesis in neurons must be tightly controlled due to neuronal sensitivity to perturbations in glycogen metabolism. Lafora disease (LD) is a fatal, congenital, neurodegenerative epilepsy. Mutations in the gene encoding the glycogen phosphatase laforin result in hyperphosphorylated glycogen that forms water-insoluble inclusions called Lafora bodies (LBs). LBs induce neuronal apoptosis and are the causative agent of LD. The mechanism of glycogen dephosphorylation by laforin and dysfunction in LD is unknown. We report the crystal structure of laforin bound to phosphoglucan product, revealing its unique integrated tertiary and quaternary structure. Structure-guided mutagenesis combined with biophysical and biochemical analyses reveal the basis for normal function of laforin in glycogen metabolism. Analyses of LD patient mutations define the mechanism by which subsets of mutations disrupt laforin function. These data provide fundamental insights connecting glycogen metabolism to neurodegenerative disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Deleterious effects of neuronal accumulation of glycogen in flies and mice.

    Science.gov (United States)

    Duran, Jordi; Tevy, María Florencia; Garcia-Rocha, Mar; Calbó, Joaquim; Milán, Marco; Guinovart, Joan J

    2012-08-01

    Under physiological conditions, most neurons keep glycogen synthase (GS) in an inactive form and do not show detectable levels of glycogen. Nevertheless, aberrant glycogen accumulation in neurons is a hallmark of patients suffering from Lafora disease or other polyglucosan disorders. Although these diseases are associated with mutations in genes involved in glycogen metabolism, the role of glycogen accumulation remains elusive. Here, we generated mouse and fly models expressing an active form of GS to force neuronal accumulation of glycogen. We present evidence that the progressive accumulation of glycogen in mouse and Drosophila neurons leads to neuronal loss, locomotion defects and reduced lifespan. Our results highlight glycogen accumulation in neurons as a direct cause of neurodegeneration. Copyright © 2012 EMBO Molecular Medicine.

  7. Ursolic acid and luteolin-7-glucoside improve lipid profiles and increase liver glycogen content through glycogen synthase kinase-3.

    Science.gov (United States)

    Azevedo, Marisa F; Camsari, Cagri; Sá, Carla M; Lima, Cristovao F; Fernandes-Ferreira, Manuel; Pereira-Wilson, Cristina

    2010-06-01

    In the present study, two phytochemicals - ursolic acid (UA) and luteolin-7-glucoside (L7G) - were assessed in vivo in healthy rats regarding effects on plasma glucose and lipid profile (total cholesterol, HDL and LDL), as well as liver glycogen content, in view of their importance in the aetiology of diabetes and associated complications. Both UA and L7G significantly decreased plasma glucose concentration. UA also significantly increased liver glycogen levels accompanied by phosphorylation of glycogen synthase kinase-3 (GSK3). The increase in glycogen deposition induced by UA (mediated by GSK3) could have contributed to the lower plasma glucose levels observed. Both compounds significantly lowered total plasma cholesterol and low-density lipoprotein levels, and, in addition, UA increased plasma high-density lipoprotein levels. Our results show that UA particularly may be useful in preventable strategies for people at risk of developing diabetes and associated cardiovascular complications by improving plasma glucose levels and lipid profile, as well as by promoting liver glycogen deposition.

  8. Modified glycogen as construction material for functional biomimetic microfibers.

    Science.gov (United States)

    Rabyk, Mariia; Hruby, Martin; Vetrik, Miroslav; Kucka, Jan; Proks, Vladimir; Parizek, Martin; Konefal, Rafal; Krist, Pavel; Chvatil, David; Bacakova, Lucie; Slouf, Miroslav; Stepanek, Petr

    2016-11-05

    We describe a conceptually new, microfibrous, biodegradable functional material prepared from a modified storage polysaccharide also present in humans (glycogen) showing strong potential as direct-contact dressing/interface material for wound healing. Double bonds were introduced into glycogen via allylation and were further exploited for crosslinking of the microfibers. Triple bonds were introduced by propargylation and served for further click functionalization of the microfibers with bioactive peptide. A simple solvent-free method allowing the preparation of thick layers was used to produce microfibers (diameter ca 2μm) from allylated and/or propargylated glycogen. Crosslinking of the samples was performed by microtron beta-irradiation, and the irradiation dose was optimized to 2kGy. The results from biological testing showed that these highly porous, hydrophilic, readily functionalizable materials were completely nontoxic to cells growing in their presence. The fibers were gradually degraded in the presence of cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Serum glucose and liver glycogen in gamma irradiated rats

    International Nuclear Information System (INIS)

    Ahlersova, E.; Ahlers, I.; Molcanova, A.

    1988-01-01

    Overnight fasted male rats of Wistar strain were irradiated with single whole-body doses of 4.78-7.17-9.57 and 14.35 Gy of gamma rays. After decapitation at intervals 1-28 d (4.78 and 7.17 Gy), 1-7 d (9.57 Gy) and 1-3 d (14.35 Gy) glucose concentration in serum and glycogen concentration in liver of irradiated and non-irradiated animals were determined. The higher was radiation dose the more expressive extent and depth of changes (hyperglycemia, accumulation of glycogen) occured. Blood glucose and liver glycogen may serve as a reliable and dose-dependent biological indicators of metabolic changes in irradiated rats. (author)

  10. Muscle glycogen depletion and lactate concentration during downhill skiing.

    Science.gov (United States)

    Tesch, P; Larsson, L; Eriksson, A; Karlsson, J

    1978-01-01

    Skilled and unskilled skiers were studied during downhill skiing. Muscle glycogen and muscle lactate concentrations in the vastus lateralis muscle were determined following different skiing conditions. Heavy glycogen utilization was found in the groups studied during a day of skiing. The skilled and unskilled skiers differed with respect to selective glycogen depletion pattern and the skilled subjects demonstrated greater depletion of slow twitch fibers than the unskilled subjects. Lactate concentrations ranged from approximately 5-26 mmoles x kg-1 wet muscle after approximately one minute of maximal skiing. This wide range was not found to be related to the level of skiing proficiency. However, skiing with varyingly angled boots, resulting in different knee angles, did affect lactate concentration. Lactate concentration was positively correlated to individual muscle fiber composition expressed as a percent of fast twitch fibers. The results suggest more pronounced involvement of aerobic energy metabolism in skilled skiers than in unskilled skiers.

  11. NAD(+) Replenishment Improves Lifespan and Healthspan in Ataxia Telangiectasia Models via Mitophagy and DNA Repair

    DEFF Research Database (Denmark)

    Fang, Evandro Fei; Kassahun, Henok; Croteau, Deborah L

    2016-01-01

    and neurodegeneration in A-T patients is unclear. Here we report and examine the significance of increased PARylation, low NAD(+), and mitochondrial dysfunction in ATM-deficient neurons, mice, and worms. Treatments that replenish intracellular NAD(+) reduce the severity of A-T neuropathology, normalize neuromuscular...... function, delay memory loss, and extend lifespan in both animal models. Mechanistically, treatments that increase intracellular NAD(+) also stimulate neuronal DNA repair and improve mitochondrial quality via mitophagy. This work links two major theories on aging, DNA damage accumulation, and mitochondrial...

  12. An Innovative Heuristic in Multi-Item Replenishment Problem for One Warehouse and N Retailers

    Directory of Open Access Journals (Sweden)

    Yugowati Praharsi

    2014-01-01

    Full Text Available Joint replenishment problem (JRP is a type of inventory model which aims to minimize the total inventory cost consisting of major ordering cost, minor ordering cost and inventory holding cost. Different from previous papers, this study considers one warehouse, multi items and N retailers. An innovative heuristic approach is developed to solve the problem. In this paper, we consider a multi echelon inventory system and seek to find a balance between the order cost and the inventory holding costs at each installation. The computational results show that the innovative heuristic provides a near exact optimal solution, but is more efficient in terms of the computational time and the iteration number.

  13. Value-based Q(s,S) policy for joint replenishments

    DEFF Research Database (Denmark)

    Johansen, Søren Glud; Thorstenson, Anders

    replenishment order is issued, if the expected cost of ordering immediately according to the (s, S) policy is less than the expected cost of deferring the order until the next demand or until the level Q is reached. We use simulation to evaluate our policy. Applying the value-based Q(s, S) policy to a standard...... set of 12-item numerical examples from the literature, the long-run average cost of the best known solution is reduced by approximately 1%. Further examples are also investigated and in some cases for which the cost structure implies a high service level, the cost reduction exceeds 10% of the cost...

  14. Locating replenishment stations for electric vehicles: Application to Danish traffic data

    DEFF Research Database (Denmark)

    Wen, Min; Laporte, Gilbert; Madsen, Oli B.G.

    2012-01-01

    for electric vehicles on a traffic network with flow-based demand. The objective is to optimize the network performance, for example to maximize the flow covered by a prefixed number of stations, or to minimize the number of stations needed to cover traffic flows. Two mixed integer linear programming......Environment-friendly electric vehicles have gained substantial attention in governments, industry and universities. The deployment of a network of recharging stations is essential given their limited travel range. This paper considers the problem of locating electronic replenishment stations...

  15. Molecular cloning and characterization of glycogen synthase in Eriocheir sinensis.

    Science.gov (United States)

    Li, Ran; Zhu, Li-Na; Ren, Li-Qi; Weng, Jie-Yang; Sun, Jin-Sheng

    2017-12-01

    Glycogen plays an important role in glucose and energy homeostasis at cellular and organismal levels. In glycogen synthesis, glycogen synthase (GS) is a rate-limiting enzyme catalysing the addition of α-1,4-linked glucose units from (UDP) 3 -glucose to a nascent glycogen chain using glycogenin (GN) as a primer. While studies on mammalian liver GS (GYS2) are numerous, enzymes from crustaceans, which also use glycogen and glucose as their main energy source, have received less attention. In the present study, we amplified full-length GS cDNA from Eriocheir sinensis. Tissue expression profiling revealed the highest expression of GS in the hepatopancreas. During moulting, GS expression and activity declined, and glycogen levels in the hepatopancreas were reduced. Recombinant GS was expressed in Escherichia coli Rosetta (DE3), and induction at 37°C or 16°C yielded EsGS in insoluble inclusion bodies (EsGS-I) or in soluble form (EsGS-S), respectively. Enzyme activity was measured in a cell-free system containing glucose-6-phosphate (G6P), and both forms possessed glycosyltransferase activity, but refolded EsGS-I was more active. Enzyme activity of both GS and EsGS-I in the hepatopancreas was optimum at 25°C, which is coincident with the optimum growth temperature of Chinese mitten crab, and higher (37°C) or lower (16°C) temperatures resulted in lower enzyme activity. Taken together, the results suggest that GS may be important for maintaining normal physiological functions such as growth and reproduction. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. A functional glycogen biosynthesis pathway in Lactobacillus acidophilus: expression and analysis of the glg operon

    OpenAIRE

    Goh, Yong Jun; Klaenhammer, Todd R

    2013-01-01

    Glycogen metabolism contributes to energy storage and various physiological functions in some prokaryotes, including colonization persistence. A role for glycogen metabolism is proposed on the survival and fitness of Lactobacillus acidophilus, a probiotic microbe, in the human gastrointestinal environment. L.?acidophilus?NCFM possesses a glycogen metabolism (glg) operon consisting of glgBCDAP - amy - pgm genes. Expression of the glg operon and glycogen accumulation were carbon source- and gro...

  17. Glycogen-bound polyphosphate kinase from the archaebacterium Sulfolobus acidocaldarius.

    Science.gov (United States)

    Skórko, R; Osipiuk, J; Stetter, K O

    1989-09-01

    Glycogen-bound polyphosphate kinase has been isolated from a crude extract of Sulfolobus acidocaldarius by isopycnic centrifugation in CsCl. Divalent cations (Mn2+ greater than Mg2+) stimulated the reaction. The enzyme does not require the presence of histones for its activity; it is inhibited strongly by phosphate and slightly by fluoride. The protein from the glycogen complex migrated in a sodium dodecyl sulfate-polyacrylamide gel as a 57-kilodalton protein band; after isoelectric focusing it separated into several spots in the pH range of 5.6 to 6.7.

  18. Glycogen storage disease type III. A case report.

    Science.gov (United States)

    de Waal, A; Röhm, G F; Hoek, B B; Potgieter, G M; Oosthuysen, W T

    1984-01-07

    A 5-year-old Black boy presented with massive hepatomegaly and muscle weakness. Liver biopsy revealed the presence of glycogen pools in the cytoplasm and nuclei of hepatocytes. Erythrocyte glycogen levels, identified as limit dextrin, were grossly increased. The galactose tolerance test as well as the two-stage glucagon stimulation test suggested a decrease in activity of both amylo-1,6-glucosidase and glucose-6-phosphatase enzymes. This was confirmed by direct assays performed on liver tissue and erythrocytes. The decrease in glucose-6-phosphatase activity was attributed to a secondary effect of limit dextrin.

  19. Enzymatic description of the anhydrofructose pathway of glycogen degradation. I

    DEFF Research Database (Denmark)

    Yu, Shukun; Refdahl, Charlotte; Lundt, Inge

    2004-01-01

    The anhydrofructose pathway describes the degradation of glycogen and starch to metabolites via 1,5-anhydro-D-fructose (1,5AnFru). The enzyme catalyzing the first reaction step of this pathway, i.e., a-1,4-glucan lyase (EC 4.2.1.13), has been purified, cloned and characterized from fungi and red...... possessed all enzymes needed for conversion of glycogen to APP, an a-1,4-glucan lyase from this fungus was isolated and partially sequenced. Based on this work, a scheme of the enzymatic description of the anhydrofructose pathway in A. melaloma was proposed. Keywords: Anhydrofructose pathway; Anthracobia...

  20. Storing of free neutrons

    International Nuclear Information System (INIS)

    Trinks, U.

    1978-12-01

    The applied method makes use of the interaction between the magnetic moment μ vector of the neutron and a magnetic field B vector. By means of superconducting magnets there can easily be achieved potential walls of μ B approximately 2 x 10 -7 eV. The principle of magnetic storing was first used for the storage ring NESTOR and showed immediate success: the stored neutrons decreased exponentially with a time constant tau = (907 +- 70) sec corresponding to the natural lifetime of the neutrons within the statistical errors. This means that there occurred no measurable additional losses (e.g. by resonance excitation) Neutrons therefore could be observed in the storage ring during about 5 half-lives (in principle of course longer, too). The orbit dynamics for neutrons in the storage ring is smilar to that in circular accelerators for charged particles. It is so well understood that the problem of the storage ring for uncharged particles (with magnetic moment) may be considered to e solved. (orig./HSI) [de

  1. Differences between glycogen biogenesis in fast- and slow-twitch rabbit muscle

    DEFF Research Database (Denmark)

    Cussó, R; Lerner, L R; Cadefau, J

    2003-01-01

    Skeletal muscle glycogen is an essential energy substrate for muscular activity. The biochemical properties of the enzymes involved in de novo synthesis of glycogen were analysed in two types of rabbit skeletal muscle fiber (fast- and slow-twitch). Glycogen concentration was higher in fast...

  2. Optimizing Multi-Product Multi-Constraint Inventory Control Systems with Stochastic Replenishments

    Science.gov (United States)

    Allah Taleizadeh, Ata; Aryanezhad, Mir-Bahador; Niaki, Seyed Taghi Akhavan

    Multi-periodic inventory control problems are mainly studied employing two assumptions. The first is the continuous review, where depending on the inventory level orders can happen at any time and the other is the periodic review, where orders can only happen at the beginning of each period. In this study, we relax these assumptions and assume that the periodic replenishments are stochastic in nature. Furthermore, we assume that the periods between two replenishments are independent and identically random variables. For the problem at hand, the decision variables are of integer-type and there are two kinds of space and service level constraints for each product. We develop a model of the problem in which a combination of back-order and lost-sales are considered for the shortages. Then, we show that the model is of an integer-nonlinear-programming type and in order to solve it, a search algorithm can be utilized. We employ a simulated annealing approach and provide a numerical example to demonstrate the applicability of the proposed methodology.

  3. Nigral dopaminergic neuron replenishment in adult mice through VE-cadherin-expressing neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Abir A Rahman

    2017-01-01

    Full Text Available The function of dopaminergic neurons in the substantia nigra is of central importance to the coordination of movement by the brain's basal ganglia circuitry. This is evidenced by the loss of these neurons, resulting in the cardinal motor deficits associated with Parkinson's disease. In order to fully understand the physiology of these key neurons and develop potential therapies for their loss, it is essential to determine if and how dopaminergic neurons are replenished in the adult brain. Recent work has presented evidence for adult neurogenesis of these neurons by Nestin+/Sox2– neural progenitor cells. We sought to further validate this finding and explore a potential atypical origin for these progenitor cells. Since neural progenitor cells have a proximal association with the vasculature of the brain and subsets of endothelial cells are Nestin+, we hypothesized that dopaminergic neural progenitors might share a common cell lineage. Therefore, we employed a VE-cadherin promoter-driven CREERT2:THlox/THlox transgenic mouse line to ablate the tyrosine hydroxylase gene from endothelial cells in adult animals. After 26 weeks, but not 13 weeks, following the genetic blockade of tyrosine hydroxylase expression in VE-cadherin+ cells, we observed a significant reduction in tyrosine hydroxylase+ neurons in the substantia nigra. The results from this genetic lineage tracing study suggest that dopaminergic neurons are replenished in adult mice by a VE-cadherin+ progenitor cell population potentially arising from an endothelial lineage.

  4. Modeling and Optimization of the Multiobjective Stochastic Joint Replenishment and Delivery Problem under Supply Chain Environment

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2013-01-01

    Full Text Available As a practical inventory and transportation problem, it is important to synthesize several objectives for the joint replenishment and delivery (JRD decision. In this paper, a new multiobjective stochastic JRD (MSJRD of the one-warehouse and n-retailer systems considering the balance of service level and total cost simultaneously is proposed. The goal of this problem is to decide the reasonable replenishment interval, safety stock factor, and traveling routing. Secondly, two approaches are designed to handle this complex multi-objective optimization problem. Linear programming (LP approach converts the multi-objective to single objective, while a multi-objective evolution algorithm (MOEA solves a multi-objective problem directly. Thirdly, three intelligent optimization algorithms, differential evolution algorithm (DE, hybrid DE (HDE, and genetic algorithm (GA, are utilized in LP-based and MOEA-based approaches. Results of the MSJRD with LP-based and MOEA-based approaches are compared by a contrastive numerical example. To analyses the nondominated solution of MOEA, a metric is also used to measure the distribution of the last generation solution. Results show that HDE outperforms DE and GA whenever LP or MOEA is adopted.

  5. Ethane's 12C/13C Ratio in Titan: Implications for Methane Replenishment

    Science.gov (United States)

    Jennings, Donald E.; Nixon, C. A.; Romani, P. N.; Bjoraker, G. L.; Sada, P. V.; Lunsford, A. W.; Boyle, R. J.; Hesman, B. E.; McCabe, G. H.

    2009-01-01

    As the .main destination of carbon in the destruction of methane in the atmosphere of Titan, ethane provides information about the carbon isotopic composition of the reservoir from which methane is replenished. If the amount of methane entering the atmosphere is presently equal to the amount converted to ethane, the 12C/13C ratio in ethane should be close to the ratio in the reservoir. We have measured the 12C/13C ratio in ethane both with Cassini CIRS(exp 1) and from the ground and find that it is very close to the telluric standard and outer planet values (89), consistent with a primordial origin for the methane reservoir. The lower 12C/13C ratio measured for methane by Huygens GCMS (82.3) can be explained if the conversion of CH4 to CH3 (and C2H6) favors 12C over 13C with a carbon kinetic isotope effect of 1.08. The time required for the atmospheric methane to reach equilibrium, i.e., for replenishment to equal destruction, is approximately 5 methane atmospheric lifetimes.

  6. Store manager performance and satisfaction: effects on store employee performance and satisfaction, store customer satisfaction, and store customer spending growth.

    Science.gov (United States)

    Netemeyer, Richard G; Maxham, James G; Lichtenstein, Donald R

    2010-05-01

    Based on emotional contagion theory and the value-profit chain literatures, the present study posits a number of hypotheses that show how managers in the small store, small number of employees retail context may affect store employees, customers, and potentially store performance. With data from 306 store managers, 1,615 store customer-contact employees, and 57,656 customers of a single retail chain, the authors examined relationships among store manager job satisfaction and job performance, store customer-contact employee job satisfaction and job performance, customer satisfaction with the retailer, and a customer-spending-based store performance metric (customer spending growth over a 2-year period). Via path analysis, several hypothesized direct and interaction relations among these constructs are supported. The results suggest implications for academic researchers and retail managers. PsycINFO Database Record (c) 2010 APA, all rights reserved.

  7. Superconducting energy store

    International Nuclear Information System (INIS)

    Elsel, W.

    1986-01-01

    The advantages obtained by the energy store device according to the invention with a superconducting solenoid system consist of the fact that only relatively short superconducting forward and return leads are required, which are collected into cables as far as possible. This limits the coolant losses of the cables. Only one relatively expensive connecting part with a transition of its conductors from room temperature to a low temperature is required, which, like the normal conducting current switch, is easily accessible. As the continuation has to be cooled independently of the upper part solenoid, cooling of this continuation part can prevent the introduction of large quantities of heat into the connected part solenoid. Due to the cooling of the forward and return conductors of the connecting cable with the coolant of the lower part solenoid, there are relatively few separations between the coolant spaces of the part solenoids. (orig./MM) [de

  8. Shopping in discount stores

    DEFF Research Database (Denmark)

    Zielke, Stephan

    2014-01-01

    quarters of intentions to shop in discount stores. Value perception has the strongest total effect, which is partly mediated by enjoyment, shame and guilt. Attributions influence the shopping intention indirectly via value perception and emotions. The inferior quality attribution has the strongest total......This paper analyzes the impact of price-related attributions, emotions and value perception on the intention to shop at grocery discounters in an integrated framework. Moderating effects of price consciousness are also analyzed. The results show that the proposed model explains almost three...... effect, followed by the efficiency of the business model attribution. The unfairness to stakeholders and the tricks in price communication attribution mostly influence the shopping intention for less price-conscious customers....

  9. Examination of liver and muscle glycogen and blood glucose levels ...

    African Journals Online (AJOL)

    Administrator

    2011-09-05

    Sep 5, 2011 ... changes in fish affect the conversion of liver glycogen into blood ... province, altitude 1248 m and surface area of 86 km2, 20 km in length 4.5 km in width ... alcohol (95% pure) were added, followed by boiling for a further 15 min. ..... water temperature on the blood glucose level of chub (Leuciscus cephalus ...

  10. Mountain bike racing - the influence of prior glycogen-inducing ...

    African Journals Online (AJOL)

    Objective. To investigate the effect of pre-exercise glutamine supplementation and the influence of a prior acute bout of glycogen-reducing exercise on the general stress and immune response to acute high-intensity cycling. Design. Randomised, double-blind, cross-over supplementation study. Setting and intervention.

  11. Dysfunctional Muscle and Liver Glycogen Metabolism in mdx Dystrophic Mice

    Science.gov (United States)

    Stapleton, David I.; Lau, Xianzhong; Flores, Marcelo; Trieu, Jennifer; Gehrig, Stefan M.; Chee, Annabel; Naim, Timur; Lynch, Gordon S.; Koopman, René

    2014-01-01

    Background Duchenne muscular dystrophy (DMD) is a severe, genetic muscle wasting disorder characterised by progressive muscle weakness. DMD is caused by mutations in the dystrophin (dmd) gene resulting in very low levels or a complete absence of the dystrophin protein, a key structural element of muscle fibres which is responsible for the proper transmission of force. In the absence of dystrophin, muscle fibres become damaged easily during contraction resulting in their degeneration. DMD patients and mdx mice (an animal model of DMD) exhibit altered metabolic disturbances that cannot be attributed to the loss of dystrophin directly. We tested the hypothesis that glycogen metabolism is defective in mdx dystrophic mice. Results Dystrophic mdx mice had increased skeletal muscle glycogen (79%, (Pglycogen synthesis is initiated by glycogenin, the expression of which was increased by 50% in mdx mice (PGlycogen synthase activity was 12% higher (Pglycogen branching enzyme activity was 70% lower (Pglycogen breakdown, glycogen phosphorylase, had 62% lower activity (Pglycogen debranching enzyme expression was 50% higher (Pglycogen (Pglycogen metabolism in mdx mice identified reduced glycogenin protein expression (46% less; Pglycogen but reduced amounts of liver glycogen. PMID:24626262

  12. Increased hepatic glycogen synthetase and decreased phosphorylase in trained rats

    DEFF Research Database (Denmark)

    Galbo, H; Saugmann, P; Richter, Erik

    1979-01-01

    Rats were either physically trained by a 12 wk swimming program or were freely eating or weight matched, sedentary controls. Trained rats had a higher relative liver weight and total hepatic glycogen synthetase (EC 2.4.1.11) activity and a lower phosphorylase (EC 2.4.1.1) activity than the other...

  13. Muscle glycogen depletion patterns during draught work in Standardbred horses.

    Science.gov (United States)

    Gottlieb, M

    1989-03-01

    Muscle fibre recruitment was investigated during draught loaded exercise by studying glycogen depletion patterns from histochemical stains of muscle biopsies from the gluteus and semitendinosus muscles. Three Standardbred trotters performed several intervals of draught loaded exercise on a treadmill with 34 kp at a trot (7 m/sec) and with 34 and 80 kp, respectively at a walk (2m/sec). Exercise was continued until the horses were unwilling to continue. Glycogen depletion was seen in all three fibre types when trotting with 34 kp for 5 or 10 mins. When an equal weight resistance was pulled at a walk, glycogen depletion was first seen in type I fibres only, then followed by a small percentage of type IIA fibres after at least 1 h. When 80 kp was pulled at a walk both type I and IIA fibres showed glycogen depletion, and after at least 30 mins exercise a small percentage of type IIB fibres was also depleted. These results indicate that the muscle fibres are depleted, in order, from type I through IIA to IIB as the intensity or duration of draught work increases.

  14. Quantification of the glycogen cascade system: the ultrasensitive responses of liver glycogen synthase and muscle phosphorylase are due to distinctive regulatory designs

    Directory of Open Access Journals (Sweden)

    Venkatesh KV

    2005-05-01

    Full Text Available Abstract Background Signaling pathways include intricate networks of reversible covalent modification cycles. Such multicyclic enzyme cascades amplify the input stimulus, cause integration of multiple signals and exhibit sensitive output responses. Regulation of glycogen synthase and phosphorylase by reversible covalent modification cycles exemplifies signal transduction by enzyme cascades. Although this system for regulating glycogen synthesis and breakdown appears similar in all tissues, subtle differences have been identified. For example, phosphatase-1, a dephosphorylating enzyme of the system, is regulated quite differently in muscle and liver. Do these small differences in regulatory architecture affect the overall performance of the glycogen cascade in a specific tissue? We address this question by analyzing the regulatory structure of the glycogen cascade system in liver and muscle cells at steady state. Results The glycogen cascade system in liver and muscle cells was analyzed at steady state and the results were compared with literature data. We found that the cascade system exhibits highly sensitive switch-like responses to changes in cyclic AMP concentration and the outputs are surprisingly different in the two tissues. In muscle, glycogen phosphorylase is more sensitive than glycogen synthase to cyclic AMP, while the opposite is observed in liver. Furthermore, when the liver undergoes a transition from starved to fed-state, the futile cycle of simultaneous glycogen synthesis and degradation switches to reciprocal regulation. Under such a transition, different proportions of active glycogen synthase and phosphorylase can coexist due to the varying inhibition of glycogen-synthase phosphatase by active phosphorylase. Conclusion The highly sensitive responses of glycogen synthase in liver and phosphorylase in muscle to primary stimuli can be attributed to distinctive regulatory designs in the glycogen cascade system. The different

  15. Rerouting of carbon flux in a glycogen mutant of cyanobacteria assessed via isotopically non-stationary 13 C metabolic flux analysis.

    Science.gov (United States)

    Hendry, John I; Prasannan, Charulata; Ma, Fangfang; Möllers, K Benedikt; Jaiswal, Damini; Digmurti, Madhuri; Allen, Doug K; Frigaard, Niels-Ulrik; Dasgupta, Santanu; Wangikar, Pramod P

    2017-10-01

    Cyanobacteria, which constitute a quantitatively dominant phylum, have attracted attention in biofuel applications due to favorable physiological characteristics, high photosynthetic efficiency and amenability to genetic manipulations. However, quantitative aspects of cyanobacterial metabolism have received limited attention. In the present study, we have performed isotopically non-stationary 13 C metabolic flux analysis (INST- 13 C-MFA) to analyze rerouting of carbon in a glycogen synthase deficient mutant strain (glgA-I glgA-II) of the model cyanobacterium Synechococcus sp. PCC 7002. During balanced photoautotrophic growth, 10-20% of the fixed carbon is stored in the form of glycogen via a pathway that is conserved across the cyanobacterial phylum. Our results show that deletion of glycogen synthase gene orchestrates cascading effects on carbon distribution in various parts of the metabolic network. Carbon that was originally destined to be incorporated into glycogen gets partially diverted toward alternate storage molecules such as glucosylglycerol and sucrose. The rest is partitioned within the metabolic network, primarily via glycolysis and tricarboxylic acid cycle. A lowered flux toward carbohydrate synthesis and an altered distribution at the glucose-1-phosphate node indicate flexibility in the network. Further, reversibility of glycogen biosynthesis reactions points toward the presence of futile cycles. Similar redistribution of carbon was also predicted by Flux Balance Analysis. The results are significant to metabolic engineering efforts with cyanobacteria where fixed carbon needs to be re-routed to products of interest. Biotechnol. Bioeng. 2017;114: 2298-2308. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. The reproductive cycle, condition index, and glycogen reserves of the cockles Cerastoderma glaucum from the Gulf of Gabès (Tunisia).

    Science.gov (United States)

    Karray, Sahar; Smaoui-Damak, Wafa; Rebai, Tarek; Hamza-Chaffai, Amel

    2015-11-01

    The gametogenic cycle of the Cerastoderma glaucum was analyzed using both qualitative and semi-quantitative methods. The condition index and glycogen concentrations were determined in order to provide information on energy storage. The cockles were collected monthly from a Bayyadha site located 15 km south of Sfax City (Gulf of Gabès) between January 2007 and January 2008. From histological point of view, we applied two approaches: (i) the qualitative method describing the various stages of gamete development for males and females during a cycle of 13 months, and (ii) the semi-quantitative method concerning the estimation of different tissue surfaces. The results showed that there is evidence of three periods of reproduction in this population. A comparison between the surfaces occupied by the three organs showed that the foot and the gonad surfaces are higher than the surface of the adductor muscle. This could suggest that these two organs are more involved in the process of glycogen reserve storage. The results of the glycogen concentrations in the different tissues (gonad, adductor muscle, and "remainders") show that during the second and third periods of reproduction, glycogen was stored in the adductor muscle and in the remainder during sexual rest, and in the gonad during the gametogenesis phases in order to supply the reproductive effort. On the contrary, in the first period of reproduction, the low concentrations of glycogen recorded in the gonad coincided with its high degree of development. This fact could be related to environmental conditions (low temperature and food) recorded during this period.

  17. Carbohydrate supercompensation and muscle glycogen utilization during exhaustive running in highly trained athletes

    DEFF Research Database (Denmark)

    Madsen, K; Pedersen, P K; Rose, P

    1990-01-01

    regimen (Norm), the other after a diet and training programme intended to increase muscle glycogen levels (Carb). Muscle glycogen concentration in the gastrocnemius muscle increased by 25% (P less than 0.05) from 581 mmol.kg-1 dry weight, SEM 50 to 722 mmol.kg-1 dry weight, SEM 34 after Carb. Running time...... (0.92, SEM 0.01 vs 0.89, SEM 0.01; P less than 0.05). Since muscle glycogen utilization was identical in the two tests, the indication of higher utilization of total carbohydrate appears to be related to a higher utilization of liver glycogen. We have concluded that glycogen depletion...

  18. Effect of carbon tetrachloride on glycogen metabolism in fasted and refed mice

    International Nuclear Information System (INIS)

    Pushpendran, C.K.; Shenoy, B.V.; Eapen, J.

    1977-01-01

    Hepatic glycogen was depleted rapidly in fasted mice treated with CCl 4 . Glycogen breakdown was slow when CCl 4 was administered after 1 hr of refeeding. There was an initial increase and then a reduction in liver glycogen of mice refed for 2 hr prior to CCl 4 injection. The incorporation of glucose-U- 14 C into glycogen was higher in mice which were refed before CCl 4 administration than in fasted mice treated with the hepatotoxin. The specific activity of lactate was higher in CCl 4 treated mice. The data suggested differences in glycogen metabolism of fasted and refed mice in response to CCl 4 treatment. (author)

  19. The importance of store windows in creating store identity and store attractiveness

    Directory of Open Access Journals (Sweden)

    Renko Sanda

    2012-01-01

    Full Text Available While choosing the store, customer first notices the store window and it plays an important role in retailing strategy. Store's window is what customers see first in meeting with the store. Store window design can lead customer to enter the store, and can give a lot of information about store brands and products. Besides the analysis of the way how specific elements of the window design affect customers and their perception, the explanation of their attraction and rejection to customers is given. If we consider the importance of the topics, we can point out the lack of literature about store windows as the communication tool which allow store to communicate with its customers and to create its retailing strategy as well. There is the scientific contribution of this paper. The paper gives theoretical comprehensions completed with the results of the study about the importance of store windows for retailers as well as for customers. Therefore, for the purpose of this paper, a two-phase research study, including a qualitative and a quantitative approach, was used: 1 the qualitative study among retailers which indicated the most important elements of store windows, the level of financial sources invested in the window design, the basis for the decisions about store window design, etc.; 2 the quantitative study on the sample of consumers conducted with on-line questionnaire. Findings suggest that store window attractiveness is the main motif for store visits. The results of the research confirm that by means of store window and its elements (with special emphasis on price and pricing actions retail store sends messages to its consumers.

  20. Glycogen Synthase in Sertoli Cells: More Than Glycogenesis?

    Science.gov (United States)

    Maldonado, Rodrigo; Mancilla, Héctor; Villarroel-Espíndola, Franz; Slebe, Felipe; Slebe, Juan Carlos; Méndez, Raúl; Guinovart, Joan J; Concha, Ilona I

    2016-11-01

    Sertoli cell metabolism actively maintains the nutritional needs of germ cells. It has been described that after glucose incorporation in Sertoli cells, less than 1% is converted to glycogen suggesting low levels of glycogen synthase activity. Phosphorylation of muscle glycogen synthase (MGS) at serine 640 (pS640MGS) decreases its activity, and this form of the enzyme was discovered as a non-ribosomal protein that modulates the translation of a subset of transcripts in HeLa cells. The aim of our study was to functionally characterize MGS in cultured Sertoli cells, as well as to explore this new feature related to RNA molecules. We detected MGS in the cytoplasm of Sertoli cells as well as in the nuclei. The activity rates of the enzyme were extremely low indicating that MGS is expressed but almost inactive. Protein targeting to glycogen (PTG) overexpression was performed to activate MGS by dephosphorylation. PTG induced glycogen synthesis massively, confirming that this enzyme is present but inactive. This finding correlates with high levels of pS640MGS, which were assayed by phosphatase treatment. To explore a putative new function for MGS in Sertoli cells, we performed RNA immunoprecipitation coupled to microarray studies. The results revealed that MGS co-immunoprecipitated with the several mRNAs and also rRNAs. These findings indicate that MGS is expressed Sertoli cells but in an inactive form, and also support a possibly novel feature of this metabolic enzyme associated with RNA-related molecules. J. Cell. Biochem. 117: 2597-2607, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Glycogen distribution in the microwave-fixed mouse brain reveals heterogeneous astrocytic patterns.

    Science.gov (United States)

    Oe, Yuki; Baba, Otto; Ashida, Hitoshi; Nakamura, Kouichi C; Hirase, Hajime

    2016-09-01

    In the brain, glycogen metabolism has been implied in synaptic plasticity and learning, yet the distribution of this molecule has not been fully described. We investigated cerebral glycogen of the mouse by immunohistochemistry (IHC) using two monoclonal antibodies that have different affinities depending on the glycogen size. The use of focused microwave irradiation yielded well-defined glycogen immunoreactive signals compared with the conventional periodic acid-Schiff method. The IHC signals displayed a punctate distribution localized predominantly in astrocytic processes. Glycogen immunoreactivity (IR) was high in the hippocampus, striatum, cortex, and cerebellar molecular layer, whereas it was low in the white matter and most of the subcortical structures. Additionally, glycogen distribution in the hippocampal CA3-CA1 and striatum had a 'patchy' appearance with glycogen-rich and glycogen-poor astrocytes appearing in alternation. The glycogen patches were more evident with large-molecule glycogen in young adult mice but they were hardly observable in aged mice (1-2 years old). Our results reveal brain region-dependent glycogen accumulation and possibly metabolic heterogeneity of astrocytes. GLIA 2016;64:1532-1545. © 2016 The Authors. Glia Published by Wiley Periodicals, Inc.

  2. Glycogen Synthesis in Glycogenin 1-Deficient Patients: A Role for Glycogenin 2 in Muscle.

    Science.gov (United States)

    Krag, Thomas O; Ruiz-Ruiz, Cristina; Vissing, John

    2017-08-01

    Glycogen storage disease (GSD) type XV is a rare disease caused by mutations in the GYG1 gene that codes for the core molecule of muscle glycogen, glycogenin 1. Nonetheless, glycogen is present in muscles of glycogenin 1-deficient patients, suggesting an alternative for glycogen buildup. A likely candidate is glycogenin 2, an isoform expressed in the liver and heart but not in healthy skeletal muscle. We wanted to investigate the formation of glycogen and changes in glycogen metabolism in patients with GSD type XV. Two patients with mutations in the GYG1 gene were investigated for histopathology, ultrastructure, and expression of proteins involved in glycogen synthesis and metabolism. Apart from occurrence of polyglucosan (PG) bodies in few fibers, glycogen appeared normal in most cells, and the concentration was normal in patients with GSD type XV. We found that glycogenin 1 was absent, but glycogenin 2 was present in the patients, whereas the opposite was the case in healthy controls. Electron microscopy revealed that glycogen was present between and not inside myofibrils in type II fibers, compromising the ultrastructure of these fibers, and only type I fibers contained PG bodies. We also found significant changes to the expression levels of several enzymes directly involved in glycogen and glucose metabolism. To our knowledge, this is the first report demonstrating expression of glycogenin 2 in glycogenin 1-deficient patients, suggesting that glycogenin 2 rescues the formation of glycogen in patients with glycogenin 1 deficiency. Copyright © 2017 Endocrine Society

  3. Analysis of image factors of x-ray films : study for the intelligent replenishment system of automatic film processor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Tae; Yoon, Chong Hyun; Park, Kwang BO; Auh, Yong Ho; Lee, Hyoung Jin; In, Kyung Hwan; Kim, Keon Chung [Asan Medical Center, Ulsan Univ. College of Medicine, Ulsan (Korea, Republic of)

    1998-06-01

    We analyzed image factors to determine the characteristic factors that need for intelligent replenishment system of the auto film processor. We processed the serial 300 sheets of radiographic films of chest phantom without replenishment of developing and fixation replenisher. We took the digital data by using film digitizer which scanned the films and automatically summed up the pixel values of the films. We analyzed characteristic curves, average gradients and relative speeds of individual film using densitometer and step densitometry. We also evaluated the pH of developer, fixer, and washer fluid with digital pH meter. Fixer residual rate and washing effect were measured by densitometer using the reagent methods. There was no significant reduction of the digital density numbers of the serial films without replenishment of developer and fixer. The average gradients were gradually decreased by 0.02 and relative speeds were also gradually decreased by 6.96% relative to initial standard step-densitometric measurement. The pHs of developer and fixer were reflected the inactivation of each fluid. The fixer residual rates and washing effects after processing each 25 sheets of films were in the normal range. We suggest that the digital data are not reliable due to limitation of the hardware and software of the film digitizer. We conclude that average gradient and relative speed which mean the film's contrast and sensitivity respectively are reliable factors for determining the need for the replenishment of the auto film processor. We need more study of simpler equations and programming for more intelligent replenishment system of the auto film processor.

  4. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

    Directory of Open Access Journals (Sweden)

    S. Sipka

    1997-01-01

    Full Text Available Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock.

  5. Glycogen in the Nervous System. I; Methods for Light and Electron Microscopy

    Science.gov (United States)

    Estable, Rosita F. De; Estable-Puig, J. F.; Miquel, J.

    1964-01-01

    'l'he relative value of different methods for combined light and electron microscopical studies of glycogen in the nervous tissue was investigated. Picroalcoholic fixatives preserve glycogen in a considerable amount but give an inadequate morphological image of glycogen distribution and are unsuitable for ultrastructural studies. Fixation by perfusion, with Dalton's chromeosmic fluid seems adequate for ultrastructural cytochemistry of glycogen. Furthermore it permits routine paraffin embedding of brain slices adjacent to those used for electron microscopy. Dimedone blocking is a necessary step for a selective staining of glycogen with PAS after osmic fixation. Enzymatic removal of glycogen in osmic fixed nervous tissue can be done In paraffin-embedded tissue. It can also be performed in glycolmethacrylate-embedded tissue without removal of the embedding medium. Paraphenylenediamine stains glycogen following periodic acid oxidation.

  6. Glycogen metabolism in the glucose-sensing and supply-driven β-cell.

    Science.gov (United States)

    Andersson, Lotta E; Nicholas, Lisa M; Filipsson, Karin; Sun, Jiangming; Medina, Anya; Al-Majdoub, Mahmoud; Fex, Malin; Mulder, Hindrik; Spégel, Peter

    2016-12-01

    Glycogen metabolism in β-cells may affect downstream metabolic pathways controlling insulin release. We examined glycogen metabolism in human islets and in the rodent-derived INS-1 832/13 β-cells and found them to express the same isoforms of key enzymes required for glycogen metabolism. Our findings indicate that glycogenesis is insulin-independent but influenced by extracellular glucose concentrations. Levels of glycogen synthase decrease with increasing glucose concentrations, paralleling accumulation of glycogen. We did not find cAMP-elicited glycogenolysis and insulin secretion to be causally related. In conclusion, our results reveal regulated glycogen metabolism in human islets and insulin-secreting cells. Whether glycogen metabolism affects insulin secretion under physiological conditions remains to be determined. © 2016 Federation of European Biochemical Societies.

  7. Hepatic protein phosphatase 1 regulatory subunit 3B (Ppp1r3b) promotes hepatic glycogen synthesis and thereby regulates fasting energy homeostasis.

    Science.gov (United States)

    Mehta, Minal B; Shewale, Swapnil V; Sequeira, Raymond N; Millar, John S; Hand, Nicholas J; Rader, Daniel J

    2017-06-23

    Maintenance of whole-body glucose homeostasis is critical to glycemic function. Genetic variants mapping to chromosome 8p23.1 in genome-wide association studies have been linked to glycemic traits in humans. The gene of known function closest to the mapped region, PPP1R3B (protein phosphatase 1 regulatory subunit 3B), encodes a protein (G L ) that regulates glycogen metabolism in the liver. We therefore sought to test the hypothesis that hepatic PPP1R3B is associated with glycemic traits. We generated mice with either liver-specific deletion ( Ppp1r3b Δ hep ) or liver-specific overexpression of Ppp1r3b The Ppp1r3b deletion significantly reduced glycogen synthase protein abundance, and the remaining protein was predominantly phosphorylated and inactive. As a consequence, glucose incorporation into hepatic glycogen was significantly impaired, total hepatic glycogen content was substantially decreased, and mice lacking hepatic Ppp1r3b had lower fasting plasma glucose than controls. The concomitant loss of liver glycogen impaired whole-body glucose homeostasis and increased hepatic expression of glycolytic enzymes in Ppp1r3b Δ hep mice relative to controls in the postprandial state. Eight hours of fasting significantly increased the expression of two critical gluconeogenic enzymes, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase, above the levels in control livers. Conversely, the liver-specific overexpression of Ppp1r3b enhanced hepatic glycogen storage above that of controls and, as a result, delayed the onset of fasting-induced hypoglycemia. Moreover, mice overexpressing hepatic Ppp1r3b upon long-term fasting (12-36 h) were protected from blood ketone-body accumulation, unlike control and Ppp1r3b Δ hep mice. These findings indicate a major role for Ppp1r3b in regulating hepatic glycogen stores and whole-body glucose/energy homeostasis. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Low birth weight and zygosity status is associated with defective muscle glycogen and glycogen synthase regulation in elderly twins

    DEFF Research Database (Denmark)

    Poulsen, Pernille; Wojtaszewski, Jørgen; Richter, Erik

    2007-01-01

    OBJECTIVE: An adverse intrauterine environment indicated by both low birth weight and monozygosity is associated with an age- or time-dependent reduction in glucose disposal and nonoxidative glucose metabolism in twins, suggesting impaired regulation of muscle glycogen synthesis. RESEARCH DESIGN ...

  9. Consensus guidelines for management of glycogen storage disease type 1b - European Study on Glycogen Storage Disease Type 1

    NARCIS (Netherlands)

    Visser, G; Rake, JP; Labrune, P; Leonard, JV; Moses, S; Ullrich, K; Wendel, U; Smit, GPA

    2002-01-01

    Life expectancy in glycogen storage disease type 1 (GSD-1) has improved considerably. Its relative rarity implies that no metabolic centre has experience of large series of patients and therefore experience with long-term management and follow-up at each centre is limited. There is wide variation in

  10. Guidelines for management of glycogen storage disease type I - European study on glycogen storage disease type I (ESGSD I)

    NARCIS (Netherlands)

    Rake, JP; Visser, G; Labrune, P; Leonard, JV; Ullrich, K; Smit, GPA

    2002-01-01

    Life-expectancy in glycogen storage disease type I (GSD I) has improved considerably. Its relative rarity implies that no metabolic centre has experience of large series of patients and experience with long-term management and follow-up at each centre is limited. There is wide variation in methods

  11. Exercise Training-Induced Adaptations Associated with Increases in Skeletal Muscle Glycogen Content

    Science.gov (United States)

    Manabe, Yasuko; Gollisch, Katja S.C.; Holton, Laura; Kim, Young–Bum; Brandauer, Josef; Fujii, Nobuharu L.; Hirshman, Michael F.; Goodyear, Laurie J.

    2012-01-01

    Chronic exercise training results in numerous skeletal muscle adaptations, including increases in insulin sensitivity and glycogen content. To understand the mechanism for increased muscle glycogen, we studied the effects of exercise training on glycogen regulatory proteins in rat skeletal muscle. Female Sprague Dawley rats performed voluntary wheel running for 1, 4, or 7 weeks. After 7 weeks of training, insulin-stimulated glucose uptake was increased in epitrochlearis muscle. Compared to sedentary control rats, muscle glycogen did not change after 1 week of training, but increased significantly after 4 and 7 weeks. The increases in muscle glycogen were accompanied by elevated glycogen synthase activity and protein expression. To assess the regulation of glycogen synthase, we examined its major activator, protein phosphatase 1 (PP1), and its major deactivator, glycogen synthase kinase 3 (GSK3). Consistent with glycogen synthase activity, PP1 activity was unchanged after 1 week of training but significantly increased after 4 and 7 weeks of training. Protein expression of RGL(GM), another regulatory PP1 subunit, significantly decreased after 4 and 7 weeks of training. Unlike PP1, GSK3 phosphorylation did not follow the pattern of glycogen synthase activity. The ~40% decrease in GSK-3α phosphorylation after 1 week of exercise training persisted until 7 weeks and may function as a negative feedback to elevated glycogen. Our findings suggest that exercise training-induced increases in muscle glycogen content could be regulated by multiple mechanisms including enhanced insulin sensitivity, glycogen synthase expression, allosteric activation of glycogen synthase and PP1activity. PMID:23206309

  12. Tobacco advertising in retail stores.

    Science.gov (United States)

    Cummings, K M; Sciandra, R; Lawrence, J

    1991-01-01

    Recent studies have described tobacco advertising in the print media, on billboards, and through sponsorship of cultural and sporting events. However, little attention has been given to another common and unavoidable source of tobacco advertising, that which is encountered in retail stores. In July 1987, we conducted a survey of 61 packaged goods retail stores in Buffalo, NY, to assess the prevalence and type of point-of-sale tobacco advertising. In addition, store owners or managers were surveyed to determine their store's policy regarding tobacco advertising, receipt of monetary incentives from distributors for displaying tobacco ads, and willingness to display antitobacco ads. Six types of stores were involved in the study: 10 supermarkets, 10 privately owned grocery stores, 9 chain convenience food stores that do not sell gasoline, 11 chain convenience food stores that sell gasoline, 11 chain pharmacies, and 10 private pharmacies. Two-thirds of the stores displayed tobacco posters, and 87 percent had promotional items advertising tobacco products, primarily cigarettes. Larger stores, and those that were privately owned, tended to display more posters and promotional items. Eighty percent of tobacco product displays were for cigarettes, 16 percent for smokeless tobacco products, and 4 percent for cigars and pipe tobacco. Convenience stores selling gasoline had the most separate tobacco product displays. Of tobacco product displays, 24 percent were located adjacent to candy and snack displays. Twenty-nine of the 61 store owners or managers indicated that their store had a policy regulating the display of tobacco ads and tobacco product displays.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1910192

  13. The Dangers of 'Warming and Replenishing' (wenbu ) during the Ming to Qing Epistemic Transition.

    Science.gov (United States)

    de Vries, Leslie

    2015-01-01

    Through a case study of Zhao Xianke's One Principle through Medicine ( Yiguan ) (1617?) and Xu Dachun's (1693-1771) denouncements of this text, my article zooms in on divergent discourses on the safety and efficacy of medicinal substances and compounds in late imperial China. Although Xu Dachun's fierce attacks on the popular 'warming and replenishing' ( wenbu ) therapies can be situated in an epistemic shift from the cosmology of 'Song learning' ( songxue ) towards the philology of 'Han learning' ( hanxue ) and 'evidential research' ( kaozheng ), I argue that more complex issues were at stake as well. Changed political, social, ethical, and economic realities shaped new and multifaceted perceptions of the nature of medicine, the medical profession, and the usage of medicinals in the aftermath of the Ming to Qing transition.

  14. Mapping organelle motion reveals a vesicular conveyor belt spatially replenishing secretory vesicles in stimulated chromaffin cells.

    Science.gov (United States)

    Maucort, Guillaume; Kasula, Ravikiran; Papadopulos, Andreas; Nieminen, Timo A; Rubinsztein-Dunlop, Halina; Meunier, Frederic A

    2014-01-01

    How neurosecretory cells spatially adjust their secretory vesicle pools to replenish those that have fused and released their hormonal content is currently unknown. Here we designed a novel set of image analyses to map the probability of tracked organelles undergoing a specific type of movement (free, caged or directed). We then applied our analysis to time-lapse z-stack confocal imaging of secretory vesicles from bovine Chromaffin cells to map the global changes in vesicle motion and directionality occurring upon secretagogue stimulation. We report a defined region abutting the cortical actin network that actively transports secretory vesicles and is dissipated by actin and microtubule depolymerizing drugs. The directionality of this "conveyor belt" towards the cell surface is activated by stimulation. Actin and microtubule networks therefore cooperatively probe the microenvironment to transport secretory vesicles to the periphery, providing a mechanism whereby cells globally adjust their vesicle pools in response to secretagogue stimulation.

  15. Using the Min/Max Method for Replenishment of Picking Locations

    Directory of Open Access Journals (Sweden)

    Apsalons Raitis

    2017-03-01

    Full Text Available The irregularity of removing quantities from a definite picking location in a warehouse very often results in the stock out in the particular picking address. In practice, the Red Card principle is used to determine a critical level for each picking location when it is necessary to start the replenishment of stock in the picking address. The question is how to calculate an adequate critical level. The guidelines in this paper explain in detail the solution of the problem using the Min/Max stock control method and mathematical algorithms adjusted by authors. In order to check the validity of these mathematical algorithms of the Min/Max method, the simulation modelling has been also done and presented.

  16. Optimal ordering quantities for substitutable deteriorating items under joint replenishment with cost of substitution

    Science.gov (United States)

    Mishra, Vinod Kumar

    2017-09-01

    In this paper we develop an inventory model, to determine the optimal ordering quantities, for a set of two substitutable deteriorating items. In this inventory model the inventory level of both items depleted due to demands and deterioration and when an item is out of stock, its demands are partially fulfilled by the other item and all unsatisfied demand is lost. Each substituted item incurs a cost of substitution and the demands and deterioration is considered to be deterministic and constant. Items are order jointly in each ordering cycle, to take the advantages of joint replenishment. The problem is formulated and a solution procedure is developed to determine the optimal ordering quantities that minimize the total inventory cost. We provide an extensive numerical and sensitivity analysis to illustrate the effect of different parameter on the model. The key observation on the basis of numerical analysis, there is substantial improvement in the optimal total cost of the inventory model with substitution over without substitution.

  17. Method and apparatus for replenishing the helium bath in the rotor of a superconducting generator

    International Nuclear Information System (INIS)

    Hofmann, A.; Schnapper, C.

    1980-01-01

    In order to replenish a helium bath in the super-conducting rotor of an electrical machine, in which bath liquid helium boils at subatmospheric pressure, with liquid helium from a helium reservoir, the liquid helium in the reservoir being at ambient pressure and a part of the liquid helium changing to the vapor phase during flow from the reservoir to the bath, liquid helium is introduced into the bath at a distance from the rotor axis of rotation, the liquid and vapor phases of the helium flowing from the reservoir to the bath are separated from one another in a phase separator fixed to the rotor, and the separated vapor phase is extracted from the separator. (MM) [de

  18. Tobacco advertising in retail stores.

    OpenAIRE

    Cummings, K M; Sciandra, R; Lawrence, J

    1991-01-01

    Recent studies have described tobacco advertising in the print media, on billboards, and through sponsorship of cultural and sporting events. However, little attention has been given to another common and unavoidable source of tobacco advertising, that which is encountered in retail stores. In July 1987, we conducted a survey of 61 packaged goods retail stores in Buffalo, NY, to assess the prevalence and type of point-of-sale tobacco advertising. In addition, store owners or managers were sur...

  19. Technical and experimental features of Magnetic Resonance Spectroscopy of brain glycogen metabolism.

    Science.gov (United States)

    Soares, Ana Francisca; Gruetter, Rolf; Lei, Hongxia

    2017-07-15

    In the brain, glycogen is a source of glucose not only in emergency situations but also during normal brain activity. Altered brain glycogen metabolism is associated with energetic dysregulation in pathological conditions, such as diabetes or epilepsy. Both in humans and animals, brain glycogen levels have been assessed non-invasively by Carbon-13 Magnetic Resonance Spectroscopy ( 13 C-MRS) in vivo. With this approach, glycogen synthesis and degradation may be followed in real time, thereby providing valuable insights into brain glycogen dynamics. However, compared to the liver and muscle, where glycogen is abundant, the sensitivity for detection of brain glycogen by 13 C-MRS is inherently low. In this review we focus on strategies used to optimize the sensitivity for 13 C-MRS detection of glycogen. Namely, we explore several technical perspectives, such as magnetic field strength, field homogeneity, coil design, decoupling, and localization methods. Furthermore, we also address basic principles underlying the use of 13 C-labeled precursors to enhance the detectable glycogen signal, emphasizing specific experimental aspects relevant for obtaining kinetic information on brain glycogen. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Free Glycogen in Vaginal Fluids Is Associated with Lactobacillus Colonization and Low Vaginal pH

    Science.gov (United States)

    Mirmonsef, Paria; Hotton, Anna L.; Gilbert, Douglas; Burgad, Derick; Landay, Alan; Weber, Kathleen M.; Cohen, Mardge; Ravel, Jacques; Spear, Gregory T.

    2014-01-01

    Objective Lactobacillus dominates the lower genital tract microbiota of many women, producing a low vaginal pH, and is important for healthy pregnancy outcomes and protection against several sexually transmitted pathogens. Yet, factors that promote Lactobacillus remain poorly understood. We hypothesized that the amount of free glycogen in the lumen of the lower genital tract is an important determinant of Lactobacillus colonization and a low vaginal pH. Methods Free glycogen in lavage samples was quantified. Pyrosequencing of the 16S rRNA gene was used to identify microbiota from 21 African American women collected over 8–11 years. Results Free glycogen levels varied greatly between women and even in the same woman. Samples with the highest free glycogen had a corresponding median genital pH that was significantly lower (pH 4.4) than those with low glycogen (pH 5.8; pglycogen versus those with low glycogen (median = 0.97 vs. 0.05, pglycogen. High concentrations of glycogen corresponded to higher levels of L. crispatus and L. jensenii, but not L. iners. Conclusion These findings show that free glycogen in genital fluid is associated with a genital microbiota dominated by Lactobacillus, suggesting glycogen is important for maintaining genital health. Treatments aimed at increasing genital free glycogen might impact Lactobacillus colonization. PMID:25033265

  1. Cerebral glycogen in humans following acute and recurrent hypoglycemia: Implications on a role in hypoglycemia unawareness.

    Science.gov (United States)

    Öz, Gülin; DiNuzzo, Mauro; Kumar, Anjali; Moheet, Amir; Khowaja, Ameer; Kubisiak, Kristine; Eberly, Lynn E; Seaquist, Elizabeth R

    2017-08-01

    Supercompensated brain glycogen levels may contribute to the development of hypoglycemia-associated autonomic failure (HAAF) following recurrent hypoglycemia (RH) by providing energy for the brain during subsequent periods of hypoglycemia. To assess the role of glycogen supercompensation in the generation of HAAF, we estimated the level of brain glycogen following RH and acute hypoglycemia (AH). After undergoing 3 hyperinsulinemic, euglycemic and 3 hyperinsulinemic, hypoglycemic clamps (RH) on separate occasions at least 1 month apart, five healthy volunteers received [1- 13 C]glucose intravenously over 80+ h while maintaining euglycemia. 13 C-glycogen levels in the occipital lobe were measured by 13 C magnetic resonance spectroscopy at ∼8, 20, 32, 44, 56, 68 and 80 h at 4 T and glycogen levels estimated by fitting the data with a biophysical model that takes into account the tiered glycogen structure. Similarly, prior 13 C-glycogen data obtained following a single hypoglycemic episode (AH) were fitted with the same model. Glycogen levels did not significantly increase after RH relative to after euglycemia, while they increased by ∼16% after AH relative to after euglycemia. These data suggest that glycogen supercompensation may be blunted with repeated hypoglycemic episodes. A causal relationship between glycogen supercompensation and generation of HAAF remains to be established.

  2. The primary defect in glycogen synthase activity is not based on increased glycogen synthase kinase-3a activity in diabetic myotubes

    DEFF Research Database (Denmark)

    Gaster, Michael; Brusgaard, Klaus; Handberg, Aa.

    2004-01-01

    The mechanism responsible for the diminished activation of glycogen synthase (GS) in diabetic myotubes remains unclear, but may involve increased activity and/or expression of glycogen synthase kinase-3 (GSK-3). In myotubes established from type 2 diabetic and healthy control subjects we determined...

  3. Glycogenolysis during short-term fasting in malaria and healthy subjects - the potential regulatory role of glycogen content on glycogen breakdown: a hypothesis

    NARCIS (Netherlands)

    Sprangers, F.; Thien, H. V.; Ackermans, M. T.; Endert, E.; Sauerwein, H. P.

    2004-01-01

    Background & aims: During short-term starvation ( <24h), glucose production decreases 10-20% due to a decrease in glycogenolysis. In the fed state glycogen regulates its rate of breakdown, in order to limit glycogen accumulation. Whether in the fasted state a similar mechanism exists to preserve

  4. Dynamic replenishment, production, and pricing decisions in the face of supply disruption and random price-sensitive demand

    NARCIS (Netherlands)

    Zhu, Stuart X.

    2013-01-01

    We study a joint decision problem for replenishment, production, pricing strategies in the face of both supply and demand uncertainties. The supply of the raw material suffers from a potential supply disruption while the demand for the finished goods is price-sensitive and random. We assume that the

  5. Micron-scale copper wires printed using femtosecond laser-induced forward transfer with automated donor replenishment

    NARCIS (Netherlands)

    Grant-Jacob, J.A.; Mills, B.; Feinaeugle, M.; Sones, C.L.; Oosterhuis, G.; Hoppenbrouwers, M.B.; Eason, R.W.

    2013-01-01

    We demonstrate the use of laser-induced forward transfer (LIFT) in combination with a novel donor replenishment scheme to print continuous copper wires. Wires of mm length, a few microns wide and submicron in height have been printed using a 800 nm, 1 kHz repetition rate, 150 fs pulsed laser. A 120

  6. An Inventory-Routing Problem with Pickups and Deliveries Arising in the Replenishment of Automated Teller Machines

    NARCIS (Netherlands)

    van Anholt, Roel G.; Coelho, Leandro C.; Laporte, Gilbert; Vis, Iris F. A.

    The purpose of this paper is to introduce, model, and solve a rich multiperiod inventory-routing problem with pickups and deliveries motivated by the replenishment of automated teller machines in the Netherlands. Commodities can be brought to and from the depot, as well as being exchanged among

  7. An inventory-routing problem with pickups and deliveries arising in the replenishment of automated teller machines

    NARCIS (Netherlands)

    Van Anholt, Roel G.; Coelho, Leandro C.; Laporte, Gilbert; Vis, Iris F.A.

    2016-01-01

    The purpose of this paper is to introduce, model, and solve a rich multiperiod inventory-routing problem with pickups and deliveries motivated by the replenishment of automated teller machines in the Netherlands. Commodities can be brought to and from the depot, as well as being exchanged among

  8. Relationship between starch and lipid accumulation induced by nutrient depletion and replenishment in the microalga Parachlorella kessleri

    Czech Academy of Sciences Publication Activity Database

    Fernandes, B.; Teixeira, J.; Dragone, G.; Vicente, A. A.; Kawano, S.; Bišová, Kateřina; Přibyl, Pavel; Zachleder, Vilém; Vítová, Milada

    2013-01-01

    Roč. 144, SEP 2013 (2013), s. 268-274 ISSN 0960-8524 R&D Projects: GA MŠk LH12145; GA TA ČR TE01020080 Institutional support: RVO:61388971 ; RVO:67985939 Keywords : Lipids * Nutrient depletion * Nutrient replenishment Subject RIV: EE - Microbiology, Virology Impact factor: 5.039, year: 2013

  9. Variations in Glycogen Synthesis in Human Pluripotent Stem Cells with Altered Pluripotent States

    Science.gov (United States)

    Chen, Richard J.; Zhang, Guofeng; Garfield, Susan H.; Shi, Yi-Jun; Chen, Kevin G.; Robey, Pamela G.; Leapman, Richard D.

    2015-01-01

    Human pluripotent stem cells (hPSCs) represent very promising resources for cell-based regenerative medicine. It is essential to determine the biological implications of some fundamental physiological processes (such as glycogen metabolism) in these stem cells. In this report, we employ electron, immunofluorescence microscopy, and biochemical methods to study glycogen synthesis in hPSCs. Our results indicate that there is a high level of glycogen synthesis (0.28 to 0.62 μg/μg proteins) in undifferentiated human embryonic stem cells (hESCs) compared with the glycogen levels (0 to 0.25 μg/μg proteins) reported in human cancer cell lines. Moreover, we found that glycogen synthesis was regulated by bone morphogenetic protein 4 (BMP-4) and the glycogen synthase kinase 3 (GSK-3) pathway. Our observation of glycogen bodies and sustained expression of the pluripotent factor Oct-4 mediated by the potent GSK-3 inhibitor CHIR-99021 reveals an altered pluripotent state in hPSC culture. We further confirmed glycogen variations under different naïve pluripotent cell growth conditions based on the addition of the GSK-3 inhibitor BIO. Our data suggest that primed hPSCs treated with naïve growth conditions acquire altered pluripotent states, similar to those naïve-like hPSCs, with increased glycogen synthesis. Furthermore, we found that suppression of phosphorylated glycogen synthase was an underlying mechanism responsible for altered glycogen synthesis. Thus, our novel findings regarding the dynamic changes in glycogen metabolism provide new markers to assess the energetic and various pluripotent states in hPSCs. The components of glycogen metabolic pathways offer new assays to delineate previously unrecognized properties of hPSCs under different growth conditions. PMID:26565809

  10. Impaired glycogen breakdown and synthesis in phosphoglucomutase 1 deficiency

    DEFF Research Database (Denmark)

    Preisler, Nicolai; Cohen, Jonathan; Vissing, Christoffer Rasmus

    2017-01-01

    contracture. Comparable to patients with McArdle disease, the patient developed a 'second wind' with a spontaneous fall in exercise heart rate and perceived exertion. Like in McArdle disease, this was attributable to an increase in muscle oxidative capacity. Carbohydrate oxidation was blocked during exercise......, and the patient had exaggerated oxidation of fat to fuel exercise. Exercise heart rate and perceived exertion were lower after IV glucose and oral sucrose. Muscle glycogen level was low normal. CONCLUSIONS: The second wind phenomenon has been considered to be pathognomonic for McArdle disease, but we demonstrate...... that it can also be present in PGM1 deficiency. We show that severe loss of PGM1 activity causes blocked muscle glycogenolysis that mimics McArdle disease, but may also limit glycogen synthesis, which broadens the phenotypic spectrum of this disorder....

  11. Dorte Nors "Den store tomat"

    DEFF Research Database (Denmark)

    Michelsen, Jimmi

    2017-01-01

    Tekstgennemgang og undervisningsforløb til Dorte Nors "Den store tomat". Undervisningsforløbet er henvendt til elever i folkeskolens udskoling......Tekstgennemgang og undervisningsforløb til Dorte Nors "Den store tomat". Undervisningsforløbet er henvendt til elever i folkeskolens udskoling...

  12. Consumers’ preferences regarding department stores

    NARCIS (Netherlands)

    van Laarhoven, W.; Borgers, A.W.J.; van den Berg, P.E.W.

    2017-01-01

    The main reason for this research was the bankruptcy of one the Dutch oldest and largest chain of department stores at the end of 2015. The main goal of this research is to find what, from a consumers’ perspective, a department store should look like. A four storey (1500 m2 each) building was

  13. Forhastet regulering af de store

    DEFF Research Database (Denmark)

    Thomsen, Steen

    2013-01-01

    Christiansborg gennemfører sandsynligvis en markant skærpet regulering af de store finansielle virksomheder. Det vil virke kontraktivt og medvirke til erhvervslivets kredittørke.......Christiansborg gennemfører sandsynligvis en markant skærpet regulering af de store finansielle virksomheder. Det vil virke kontraktivt og medvirke til erhvervslivets kredittørke....

  14. Glycogen synthase kinase 3: more than a namesake.

    Science.gov (United States)

    Rayasam, Geetha Vani; Tulasi, Vamshi Krishna; Sodhi, Reena; Davis, Joseph Alex; Ray, Abhijit

    2009-03-01

    Glycogen synthase kinase 3 (GSK3), a constitutively acting multi-functional serine threonine kinase is involved in diverse physiological pathways ranging from metabolism, cell cycle, gene expression, development and oncogenesis to neuroprotection. These diverse multiple functions attributed to GSK3 can be explained by variety of substrates like glycogen synthase, tau protein and beta catenin that are phosphorylated leading to their inactivation. GSK3 has been implicated in various diseases such as diabetes, inflammation, cancer, Alzheimer's and bipolar disorder. GSK3 negatively regulates insulin-mediated glycogen synthesis and glucose homeostasis, and increased expression and activity of GSK3 has been reported in type II diabetics and obese animal models. Consequently, inhibitors of GSK3 have been demonstrated to have anti-diabetic effects in vitro and in animal models. However, inhibition of GSK3 poses a challenge as achieving selectivity of an over achieving kinase involved in various pathways with multiple substrates may lead to side effects and toxicity. The primary concern is developing inhibitors of GSK3 that are anti-diabetic but do not lead to up-regulation of oncogenes. The focus of this review is the recent advances and the challenges surrounding GSK3 as an anti-diabetic therapeutic target.

  15. Amaryllidaceae Alkaloids as Potential Glycogen Synthase Kinase-3β Inhibitors

    Directory of Open Access Journals (Sweden)

    Daniela Hulcová

    2018-03-01

    Full Text Available Glycogen synthase kinase-3β (GSK-3β is a multifunctional serine/threonine protein kinase that was originally identified as an enzyme involved in the control of glycogen metabolism. It plays a key role in diverse physiological processes including metabolism, the cell cycle, and gene expression by regulating a wide variety of well-known substances like glycogen synthase, tau-protein, and β-catenin. Recent studies have identified GSK-3β as a potential therapeutic target in Alzheimer´s disease, bipolar disorder, stroke, more than 15 types of cancer, and diabetes. GSK-3β is one of the most attractive targets for medicinal chemists in the discovery, design, and synthesis of new selective potent inhibitors. In the current study, twenty-eight Amaryllidaceae alkaloids of various structural types were studied for their potency to inhibit GSK-3β. Promising results have been demonstrated by alkaloids of the homolycorine-{9-O-demethylhomolycorine (IC50 = 30.00 ± 0.71 µM, masonine (IC50 = 27.81 ± 0.01 μM}, and lycorine-types {caranine (IC50 = 30.75 ± 0.04 μM}.

  16. Dietary Management of the Ketogenic Glycogen Storage Diseases

    Directory of Open Access Journals (Sweden)

    Kaustuv Bhattacharya MBBS, MRCPCH, FRACP, MD

    2016-08-01

    Full Text Available The glycogen storage diseases (GSDs comprise a group of rare inherited disorders of glycogen metabolism. The hepatic glycogenolytic forms of these disorders are typically associated with hypoglycemia and hepatomegaly. For GSD I, secondary metabolic disturbances include fasting hyperlactatemia, hyperuricemia, and hyperlipidemia. Glycogen storage disease III is caused by reduced activity of the debrancher enzyme, GSD VI by phosphorylase, and GSD IX by phosphorylase kinase. It has often been reported that the non-GSD I group of disorders have a benign course. However, myopathy, cardiomyopathy, and cirrhosis have been reported significant clinical morbidities associated with GSD III and IX in particular. There have been a range of reports indicating high-protein diets, high-fat diets, medium chain triglyceride (MCT, modified Atkins diet, and therapeutic ketones as rescuing severe phenotypes of GSD III in particular. The etiology of these severe phenotypes has not been defined. Cases presented in this report indicate potential harm from excessive simple sugar use in GSD IX C. Review of the literature indicates that most interventions have reduced the glycemic load and provide alternate substrates for energy in rescue situations. Prevention of complications is most likely to occur with a mixed balanced low glycemic index diet potentially with relative increases in protein.

  17. Labeling of hepatic glycogen after short- and long-term stimulation of glycogen synthesis in rats injected with 3H-galactose

    International Nuclear Information System (INIS)

    Michaels, J.E.; Garfield, S.A.; Hung, J.T.; Cardell, R.R. Jr.

    1990-01-01

    The effects of short- and long-term stimulation of glycogen synthesis elicited by dexamethasone were studied by light (LM) and electron (EM) microscopic radioautography (RAG) and biochemical analysis. Adrenalectomized rats were fasted overnight and pretreated for short- (3 hr) or long-term (14 hr) periods with dexamethasone prior to intravenous injection of tracer doses of 3H-galactose. Analysis of LM-RAGs from short-term rats revealed that about equal percentages (44%) of hepatocytes became heavily or lightly labeled 1 hr after labeling. The percentage of heavily labeled cells increased slightly 6 hr after labeling, and unlabeled glycogen became apparent in some hepatocytes. The percentage of heavily labeled cells had decreased somewhat 12 hr after labeling, and more unlabeled glycogen was evident. In the long-term rats 1 hr after labeling, a higher percentage of heavily labeled cells (76%) was observed compared to short-term rats, and most glycogen was labeled. In spite of the high amount of labeling seen initially, the percentage of heavily labeled hepatocytes had decreased considerably to 55% by 12 hr after injection; and sparsely labeled and unlabeled glycogen was prevalent. The EM-RAGs of both short- and long-term rats were similar. Silver grains were associated with glycogen patches 1 hr after labeling; 12 hr after labeling, the glycogen patches had enlarged; and label, where present, was dispersed over the enlarged glycogen clumps. Analysis of DPM/mg tissue corroborated the observed decrease in label 12 hr after administration in the long-term animals. The loss of label observed 12 hr after injection in the long-term pretreated rats suggests that turnover of glycogen occurred during this interval despite the net accumulation of glycogen that was visible morphologically and evident from biochemical measurement

  18. Use of deuterium labelled glucose in evaluating the pathway of hepatic glycogen synthesis

    International Nuclear Information System (INIS)

    Goodman, M.N.; Masuoka, L.K.; deRopp, J.S.; Jones, A.D.

    1989-01-01

    Deuterium labelled glucose has been used to study the pathway of hepatic glycogen synthesis during the fasted-refed transition in rats. Deuterium enrichment of liver glycogen was determined using nuclear magnetic resonance as well as mass spectroscopy. Sixty minutes after oral administration of deuterated glucose to fasted rats, the portal vein blood was fully enriched with deuterated glucose. Despite this, less than half of the glucose molecules incorporated into liver glycogen contained deuterium. The loss of deuterium label from glucose is consistent with hepatic glycogen synthesis by an indirect pathway requiring prior metabolism of glucose. The use of deuterium labelled glucose may prove to be a useful probe to study hepatic glycogen metabolism. Its use may also find application in the study of liver glycogen metabolism in humans by a noninvasive means

  19. Role of Autophagy in Glycogen Breakdown and Its Relevance to Chloroquine Myopathy

    Science.gov (United States)

    Zirin, Jonathan; Nieuwenhuis, Joppe; Perrimon, Norbert

    2013-01-01

    Several myopathies are associated with defects in autophagic and lysosomal degradation of glycogen, but it remains unclear how glycogen is targeted to the lysosome and what significance this process has for muscle cells. We have established a Drosophila melanogaster model to study glycogen autophagy in skeletal muscles, using chloroquine (CQ) to simulate a vacuolar myopathy that is completely dependent on the core autophagy genes. We show that autophagy is required for the most efficient degradation of glycogen in response to starvation. Furthermore, we show that CQ-induced myopathy can be improved by reduction of either autophagy or glycogen synthesis, the latter possibly due to a direct role of Glycogen Synthase in regulating autophagy through its interaction with Atg8. PMID:24265594

  20. Field and Experimental Constraints on the Dynamics of Replenished Silicic Magma Chambers

    Science.gov (United States)

    Bain, A. A.; Jellinek, M.

    2008-12-01

    The underlying causes of catastrophic caldera-forming volcanic eruptions remain poorly understood. However, the occurrence of magma mixing within bimodal systems has become increasingly linked with such eruptions. In particular, buoyancy effects related to unstable density contrasts arising as a result of silicic- basaltic magma interactions may play an important role in the growth, differentiation and catastrophic eruption of silicic magma chambers. Evidence of such magmatic interactions can be found in layered intrusions from the Coastal Maine Magmatic Province (USA), where well-exposed cross-sections reveal hundreds of laterally-extensive basaltic sheets, apparently injected as intrusive lava flows onto the growing floors of silicic magma chambers. Interfaces between mafic and silicic layers are commonly sharply defined and exhibit deformation parallel to the inferred direction of palaeo-gravity. Our field observations suggest that the cooling, settling and buckling of gravitationally-unstable mafic replenishments may have driven large-scale (basalt layer depth) and small- scale (crystal diameter) upwelling and/or overturning of underlying buoyant silicic cumulate material. In order to characterize the full range of buoyancy effects, we carried out extensive spectral analysis of high- resolution digital field measurements from the Pleasant Bay and Mount Desert Island intrusions. In many cases, Rayleigh-Taylor theory and the longest measured wavelength of deformation indicate that a large and potentially-quantifiable fraction of the original, pre-replenishment silicic cumulate thickness may be missing, implying that vertical mass transfer has occurred. In addition, the shortest wavelengths of deformation are generally consistent with observed length-scales of crystals and clumps of crystals at these localities. With the aim of understanding the initial conditions that gave rise to these field observations, we conduct a series of laboratory experiments in which we

  1. Possible mechanism for changes in glycogen metabolism in unloaded soleus muscle

    Science.gov (United States)

    Henriksen, E. J.; Tischler, M. E.

    1985-01-01

    Carbohydrate metabolism has been shown to be affected in a number of ways by different models of hypokinesia. In vivo glycogen levels in the soleus muscle are known to be increased by short-term denervation and harness suspension. In addition, exposure to 7 days of hypogravity also caused a dramatic increase in glycogen concentration in this muscle. The biochemical alterations caused by unloading that may bring about these increases in glycogen storage in the soleus were sought.

  2. Free glycogen in vaginal fluids is associated with Lactobacillus colonization and low vaginal pH.

    Directory of Open Access Journals (Sweden)

    Paria Mirmonsef

    Full Text Available Lactobacillus dominates the lower genital tract microbiota of many women, producing a low vaginal pH, and is important for healthy pregnancy outcomes and protection against several sexually transmitted pathogens. Yet, factors that promote Lactobacillus remain poorly understood. We hypothesized that the amount of free glycogen in the lumen of the lower genital tract is an important determinant of Lactobacillus colonization and a low vaginal pH.Free glycogen in lavage samples was quantified. Pyrosequencing of the 16S rRNA gene was used to identify microbiota from 21 African American women collected over 8-11 years.Free glycogen levels varied greatly between women and even in the same woman. Samples with the highest free glycogen had a corresponding median genital pH that was significantly lower (pH 4.4 than those with low glycogen (pH 5.8; p<0.001. The fraction of the microbiota consisting of Lactobacillus was highest in samples with high glycogen versus those with low glycogen (median = 0.97 vs. 0.05, p<0.001. In multivariable analysis, having 1 vs. 0 male sexual partner in the past 6 months was negatively associated, while BMI ≥30 was positively associated with glycogen. High concentrations of glycogen corresponded to higher levels of L. crispatus and L. jensenii, but not L. iners.These findings show that free glycogen in genital fluid is associated with a genital microbiota dominated by Lactobacillus, suggesting glycogen is important for maintaining genital health. Treatments aimed at increasing genital free glycogen might impact Lactobacillus colonization.

  3. Glycogen Phosphomonoester Distribution in Mouse Models of the Progressive Myoclonic Epilepsy, Lafora Disease*

    Science.gov (United States)

    DePaoli-Roach, Anna A.; Contreras, Christopher J.; Segvich, Dyann M.; Heiss, Christian; Ishihara, Mayumi; Azadi, Parastoo; Roach, Peter J.

    2015-01-01

    Glycogen is a branched polymer of glucose that acts as an energy reserve in many cell types. Glycogen contains trace amounts of covalent phosphate, in the range of 1 phosphate per 500–2000 glucose residues depending on the source. The function, if any, is unknown, but in at least one genetic disease, the progressive myoclonic epilepsy Lafora disease, excessive phosphorylation of glycogen has been implicated in the pathology by disturbing glycogen structure. Some 90% of Lafora cases are attributed to mutations of the EPM2A or EPM2B genes, and mice with either gene disrupted accumulate hyperphosphorylated glycogen. It is, therefore, of importance to understand the chemistry of glycogen phosphorylation. Rabbit skeletal muscle glycogen contained covalent phosphate as monoesters of C2, C3, and C6 carbons of glucose residues based on analyses of phospho-oligosaccharides by NMR. Furthermore, using a sensitive assay for glucose 6-P in hydrolysates of glycogen coupled with measurement of total phosphate, we determined the proportion of C6 phosphorylation in rabbit muscle glycogen to be ∼20%. C6 phosphorylation also accounted for ∼20% of the covalent phosphate in wild type mouse muscle glycogen. Glycogen phosphorylation in Epm2a−/− and Epm2b−/− mice was increased 8- and 4-fold compared with wild type mice, but the proportion of C6 phosphorylation remained unchanged at ∼20%. Therefore, our results suggest that C2, C3, and/or C6 phosphate could all contribute to abnormal glycogen structure or to Lafora disease. PMID:25416783

  4. Human skeletal muscle glycogen utilization in exhaustive exercise: role of subcellular localization and fibre type

    Science.gov (United States)

    Nielsen, Joachim; Holmberg, Hans-Christer; Schrøder, Henrik D; Saltin, Bengt; Ørtenblad, Niels

    2011-01-01

    Abstract Although glycogen is known to be heterogeneously distributed within skeletal muscle cells, there is presently little information available about the role of fibre types, utilization and resynthesis during and after exercise with respect to glycogen localization. Here, we tested the hypothesis that utilization of glycogen with different subcellular localizations during exhaustive arm and leg exercise differs and examined the influence of fibre type and carbohydrate availability on its subsequent resynthesis. When 10 elite endurance athletes (22 ± 1 years, = 68 ± 5 ml kg−1 min−1, mean ± SD) performed one hour of exhaustive arm and leg exercise, transmission electron microscopy revealed more pronounced depletion of intramyofibrillar than of intermyofibrillar and subsarcolemmal glycogen. This phenomenon was the same for type I and II fibres, although at rest prior to exercise, the former contained more intramyofibrillar and subsarcolemmal glycogen than the latter. In highly glycogen-depleted fibres, the remaining small intermyofibrillar and subsarcolemmal glycogen particles were often found to cluster in groupings. In the recovery period, when the athletes received either a carbohydrate-rich meal or only water the impaired resynthesis of glycogen with water alone was associated primarily with intramyofibrillar glycogen. In conclusion, after prolonged high-intensity exercise the depletion of glycogen is dependent on subcellular localization. In addition, the localization of glycogen appears to be influenced by fibre type prior to exercise, as well as carbohydrate availability during the subsequent period of recovery. These findings provide insight into the significance of fibre type-specific compartmentalization of glycogen metabolism in skeletal muscle during exercise and subsequent recovery. PMID:21486810

  5. Detection of human muscle glycogen by natural abundance 13C NMR

    International Nuclear Information System (INIS)

    Avison, M.J.; Rothman, D.L.; Nadel, E.; Shulman, R.G.

    1988-01-01

    Natural abundance 13 C nuclear magnetic resonance spectroscopy was used to detect signals from glycogen in the human gastrocnemius muscle. The reproducibility of the measurement was demonstrated, and the ability to detect dynamic changes was confirmed by measuring a decrease in muscle glycogen levels after exercise and its subsequent repletion. Single frequency gated 1 H decoupling was used to obtain decoupled natural abundance 13 C NMR spectra of the C-1 position of muscle glycogen

  6. Glycogen accumulation in normal and irradiated minced muscle autografts on frog gastrocnemius

    International Nuclear Information System (INIS)

    Malhotra, R.K.; Kaul, R.; Malhotra, N.

    1989-01-01

    Alterations induced in glycogen content and phosphorylase activity have been studied in normal and irradiated minced muscle autografts on frog gastrocnemius at days 1, 3, 5, 7, 10, 15 and 30 postgrafting. The changes observed in the glycogen content and phosphorylase activity conform to the degeneration and regeneration phases of muscle repair. An attempt has been made to explain the altered glycogen utilizing capacities of the frog skeletal muscle during its repair and regeneration. (author)

  7. When phosphorylated at Thr148, the β2-subunit of AMP-activated kinase does not associate with glycogen in skeletal muscle.

    Science.gov (United States)

    Xu, Hongyang; Frankenberg, Noni T; Lamb, Graham D; Gooley, Paul R; Stapleton, David I; Murphy, Robyn M

    2016-07-01

    The 5'-AMP-activated protein kinase (AMPK), a heterotrimeric complex that functions as an intracellular fuel sensor that affects metabolism, is activated in skeletal muscle in response to exercise and utilization of stored energy. The diffusibility properties of α- and β-AMPK were examined in isolated skeletal muscle fiber segments dissected from rat fast-twitch extensor digitorum longus and oxidative soleus muscles from which the surface membranes were removed by mechanical dissection. After the muscle segments were washed for 1 and 10 min, ∼60% and 75%, respectively, of the total AMPK pools were found in the diffusible fraction. After in vitro stimulation of the muscle, which resulted in an ∼80% decline in maximal force, 20% of the diffusible pool became bound in the fiber. This bound pool was not associated with glycogen, as determined by addition of a wash step containing amylase. Stimulation of extensor digitorum longus muscles resulted in 28% glycogen utilization and a 40% increase in phosphorylation of the downstream AMPK target acetyl carboxylase-CoA. This, however, had no effect on the proportion of total β2-AMPK that was phosphorylated in whole muscle homogenates measured by immunoprecipitation. These findings suggest that, in rat skeletal muscle, β2-AMPK is not associated with glycogen and that activation of AMPK by muscle contraction does not dephosphorylate β2-AMPK. These findings question the physiological relevance of the carbohydrate-binding function of β2-AMPK in skeletal muscle. Copyright © 2016 the American Physiological Society.

  8. Glycogen supercompensation in rat soleus muscle during recovery from nonweight bearing

    Science.gov (United States)

    Henriksen, Erik J.; Kirby, Christopher R.; Tischler, Marc E.

    1989-01-01

    Events leading to the normalization of the glycogen metabolism in the soleus muscle of rat, altered by 72-h three days of hind-limb suspension, were investigated during the 72-h recovery period when the animals were allowed to bear weight on all four limbs. Relative importance of the factors affecting glycogen metabolism in skeletal muscle during the recovery period was also examined. Glycogen concentration was found to decrease within 15 min and up to 2 h of recovery, while muscle glucose 6-phosphate, and the fractional activities of glycogen phosphorylase and glycogen synthase increased. From 2 to 4 h, when the glycogen synthase activity remained elevated and the phosphorylase activity declined, glycogen concentration increased, until it reached maximum values at about 24 h, after which it started to decrease, reaching control values by 72 h. At 12 and 24 h, the inverse relationship between glycogen concentration and the synthase activity ratio was lost, indicating that the reloading transiently uncoupled glycogen control of this enzyme.

  9. Glycogen distribution in the microwave‐fixed mouse brain reveals heterogeneous astrocytic patterns

    Science.gov (United States)

    Baba, Otto; Ashida, Hitoshi; Nakamura, Kouichi C.

    2016-01-01

    In the brain, glycogen metabolism has been implied in synaptic plasticity and learning, yet the distribution of this molecule has not been fully described. We investigated cerebral glycogen of the mouse by immunohistochemistry (IHC) using two monoclonal antibodies that have different affinities depending on the glycogen size. The use of focused microwave irradiation yielded well‐defined glycogen immunoreactive signals compared with the conventional periodic acid‐Schiff method. The IHC signals displayed a punctate distribution localized predominantly in astrocytic processes. Glycogen immunoreactivity (IR) was high in the hippocampus, striatum, cortex, and cerebellar molecular layer, whereas it was low in the white matter and most of the subcortical structures. Additionally, glycogen distribution in the hippocampal CA3‐CA1 and striatum had a ‘patchy’ appearance with glycogen‐rich and glycogen‐poor astrocytes appearing in alternation. The glycogen patches were more evident with large‐molecule glycogen in young adult mice but they were hardly observable in aged mice (1–2 years old). Our results reveal brain region‐dependent glycogen accumulation and possibly metabolic heterogeneity of astrocytes. GLIA 2016;64:1532–1545 PMID:27353480

  10. Joint Decisions on Emission Reduction and Inventory Replenishment with Overconfidence and Low-Carbon Preference

    Directory of Open Access Journals (Sweden)

    Shoufeng Ji

    2018-04-01

    Full Text Available This paper presents a game-theoretical analysis of joint decisions on carbon emission reduction and inventory replenishment with overconfidence and consumer’s low-carbon preference for key supply chain players when facing effort-dependent demand. We consider respectively the overconfidence of a supplier who overestimates the impacts of his emission reduction efforts on product demand and the overconfidence of a retailer who underestimates the variability of the stochastic demand. We find, surprisingly, that the supplier’s overconfidence can mitigate “double marginalization” but hurt self-profit, while the retailer’s overconfidence can be an irrelevant factor for self-profit. The retailer aiming at short-term trading should actively seek an overconfident supplier, while the supplier should actively seek a rational retailer for whom the critical fractile is more than 0.5, whereas for an overconfident retailer, the critical fractile is less than or equal to 0.5. The study also underlines the effect of regulation parameters as an important contextual factor influencing low-carbon operations.

  11. Assessment of Aquifer Age and Replenishment Rate by Utilizing 36Cl-Pulse

    International Nuclear Information System (INIS)

    Challan, M.B.; Challan, M.B.; Labib, A.A.; Labib, A.A.

    2015-01-01

    The present study aims at estimating the residence-time of groundwater based on bomb-produced 36 Cl. Water samples were collected from some selected wells located around Al-Zulfi province, Riyadh central region, Saudi Arabia. 36 The Cl/Cl ratios in the water samples were determined by Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Liquid Scintillation Counting(LSC). 36 The Cl/Cl ratios in the groundwater were estimated to be 1.0-2.0×10 -10 . The shallow unconfined aquifer of the area is mainly replenished by the water infiltration from the seasonal rains. Estimates of residence time were obtained by comparing the measured bomb-derived 36 Cl concentrations in groundwater with the background reference. Dating based on a 36 Cl bomb pulse may be more reliable and sensitive for groundwater recharged before 1975, back as far as the mid-1950s.The above 36 Cl-background concentration was deduced by determining accurately the background corrected Dye-3 ice core data from the frozen Arctic Data, according to the estimated total 3 '6Cl resources, including bomb-produced '3 6 Cl fallout. An estimated residence time of 7.81×10 4 y was obtained from extrapolated flow velocity. It was noticed that 36 Cl concentration in groundwater does not reflect the input of bomb pulse 36 Cl, it belongs to the era before 1950

  12. NAD+ Replenishment Improves Lifespan and Healthspan in Ataxia Telangiectasia Models via Mitophagy and DNA Repair.

    Science.gov (United States)

    Fang, Evandro Fei; Kassahun, Henok; Croteau, Deborah L; Scheibye-Knudsen, Morten; Marosi, Krisztina; Lu, Huiming; Shamanna, Raghavendra A; Kalyanasundaram, Sumana; Bollineni, Ravi Chand; Wilson, Mark A; Iser, Wendy B; Wollman, Bradley N; Morevati, Marya; Li, Jun; Kerr, Jesse S; Lu, Qiping; Waltz, Tyler B; Tian, Jane; Sinclair, David A; Mattson, Mark P; Nilsen, Hilde; Bohr, Vilhelm A

    2016-10-11

    Ataxia telangiectasia (A-T) is a rare autosomal recessive disease characterized by progressive neurodegeneration and cerebellar ataxia. A-T is causally linked to defects in ATM, a master regulator of the response to and repair of DNA double-strand breaks. The molecular basis of cerebellar atrophy and neurodegeneration in A-T patients is unclear. Here we report and examine the significance of increased PARylation, low NAD + , and mitochondrial dysfunction in ATM-deficient neurons, mice, and worms. Treatments that replenish intracellular NAD + reduce the severity of A-T neuropathology, normalize neuromuscular function, delay memory loss, and extend lifespan in both animal models. Mechanistically, treatments that increase intracellular NAD + also stimulate neuronal DNA repair and improve mitochondrial quality via mitophagy. This work links two major theories on aging, DNA damage accumulation, and mitochondrial dysfunction through nuclear DNA damage-induced nuclear-mitochondrial signaling, and demonstrates that they are important pathophysiological determinants in premature aging of A-T, pointing to therapeutic interventions. Published by Elsevier Inc.

  13. DMRT1 Is Required for Mouse Spermatogonial Stem Cell Maintenance and Replenishment.

    Science.gov (United States)

    Zhang, Teng; Oatley, Jon; Bardwell, Vivian J; Zarkower, David

    2016-09-01

    Male mammals produce sperm for most of postnatal life and therefore require a robust germ line stem cell system, with precise balance between self-renewal and differentiation. Prior work established doublesex- and mab-3-related transcription factor 1 (Dmrt1) as a conserved transcriptional regulator of male sexual differentiation. Here we investigate the role of Dmrt1 in mouse spermatogonial stem cell (SSC) homeostasis. We find that Dmrt1 maintains SSCs during steady state spermatogenesis, where it regulates expression of Plzf, another transcription factor required for SSC maintenance. We also find that Dmrt1 is required for recovery of spermatogenesis after germ cell depletion. Committed progenitor cells expressing Ngn3 normally do not contribute to SSCs marked by the Id4-Gfp transgene, but do so when spermatogonia are chemically depleted using busulfan. Removal of Dmrt1 from Ngn3-positive germ cells blocks the replenishment of Id4-GFP-positive SSCs and recovery of spermatogenesis after busulfan treatment. Our data therefore reveal that Dmrt1 supports SSC maintenance in two ways: allowing SSCs to remain in the stem cell pool under normal conditions; and enabling progenitor cells to help restore the stem cell pool after germ cell depletion.

  14. Estimated costs of Sustaining Agricultural Production Through Erosional Control and Replenishment of Nutrient Losses in Kenya

    International Nuclear Information System (INIS)

    Onyango, J.W.

    1999-01-01

    Soil erosion is one of the major causes of nutrient depletion in sub-Saharan Africa. Highlights of losses from erosion can be used to explain why agricultural production in this region is not sustainable. annual macronutrient losses were calculated from experimental results at 8 sites in Kenya between 1986 and 1990. these losses were used along with the current local prices of fertiliser to estimate the annual national budget required for there replenishment. On average, 5.72, 29.3 and 0.82 kg ha -1 yr -1 of N, P and K, respectively, were lost annually. These losses are determined by soil types, slope, crop cover characteristics and rainfall amounts. soil losses can be reduced by terracing, contour farming and intercropping to improve crop cover. These efforts reduce the adverse effects of sporadic rainfall on fragile soil types. in order to ensure sustainability however, control measures have to be supplemented by national additions of 64 000 t, 323 000 t and 10 000 t of N, P and K respectively per year. The equivalent costs of these fertilisers will be Ksh 1,408 Ksh 8721 Ksh 220 million for the respective nutrients. This would require a total of some US$256 million (Ksh 10 349 million) annually from the national budget

  15. The effect of motivation and positive affect on ego depletion: Replenishment versus release mechanism.

    Science.gov (United States)

    Zhu, Ze; Li, Jian; Zhang, Bo; Li, Ye; Zhang, Houcan

    2017-12-01

    In this study, 2 experiments were conducted to investigate whether motivation and positive affect can alleviate ego depletion and to elucidate their possible mechanisms. In Experiment 1, a crossing-out-letter task was adapted to reach an ego depletion state for Chinese participants. Participants were then randomly assigned to the extrinsic motivation group, the positive affect group or the depletion control group. After the experimental treatment, a dumbbell task was used to measure participants' remaining self-regulatory resources. The results showed that participants in the motivation and positive affect groups performed better on the dumbbell task than participants in the depletion control group. Experiment 2 was similar to Experiment 1 except that participants were asked to perform an additional unexpected dumbbell task after a neutral video following the above procedure. The results of Experiment 1 were replicated; however, participants' performance on the additional dumbbell task differed. The positive affect group performed better than the depletion control group, indicating an increase in self-regulatory resources and thus supporting the replenishment effect of positive affect. No significant difference was found between the motivation group and the depletion control group. © 2015 International Union of Psychological Science.

  16. An Optimization Framework for Combining the Petroleum Replenishment Problem with the Optimal Bidding in Combinatorial Auctions

    Directory of Open Access Journals (Sweden)

    Chefi Triki

    2016-08-01

    Full Text Available We address in this paper a periodic petroleum station replenishment problem (PPSRP that aims to plan the delivery of petroleum products to a set of geographically dispatched stations. It is assumed that each station is characterized by its weekly demand and by its frequency of service. The main objective of the delivery process is to minimize the total travelled distance by the vailable trucks over an extended planning horizon. The problem configuration is described through a set of trucks with several compartments each and a set of stations with demands and prefixed delivery frequencies. Given such input data, the minimization of the total distance is subject to assignment and routing constraints that express the capacity limitations of each truck's compartment in terms of the frequency and the pathways' restrictions. In this paper, we develop and solve the full space mathematical formulation for the PPSRP with application to the Omani context. Our ultimate aim is to include such a model into an integrated framework having the objective of advising petroleum distribution companies on how to prepare bids in case of participation in combinatorial auctions of the transportation procurement.

  17. Characterization of Function of the GlgA2 Glycogen/Starch Synthase in Cyanobacterium sp. Clg1 Highlights Convergent Evolution of Glycogen Metabolism into Starch Granule Aggregation.

    Science.gov (United States)

    Kadouche, Derifa; Ducatez, Mathieu; Cenci, Ugo; Tirtiaux, Catherine; Suzuki, Eiji; Nakamura, Yasunori; Putaux, Jean-Luc; Terrasson, Amandine Durand; Diaz-Troya, Sandra; Florencio, Francisco Javier; Arias, Maria Cecilia; Striebeck, Alexander; Palcic, Monica; Ball, Steven G; Colleoni, Christophe

    2016-07-01

    At variance with the starch-accumulating plants and most of the glycogen-accumulating cyanobacteria, Cyanobacterium sp. CLg1 synthesizes both glycogen and starch. We now report the selection of a starchless mutant of this cyanobacterium that retains wild-type amounts of glycogen. Unlike other mutants of this type found in plants and cyanobacteria, this mutant proved to be selectively defective for one of the two types of glycogen/starch synthase: GlgA2. This enzyme is phylogenetically related to the previously reported SSIII/SSIV starch synthase that is thought to be involved in starch granule seeding in plants. This suggests that, in addition to the selective polysaccharide debranching demonstrated to be responsible for starch rather than glycogen synthesis, the nature and properties of the elongation enzyme define a novel determinant of starch versus glycogen accumulation. We show that the phylogenies of GlgA2 and of 16S ribosomal RNA display significant congruence. This suggests that this enzyme evolved together with cyanobacteria when they diversified over 2 billion years ago. However, cyanobacteria can be ruled out as direct progenitors of the SSIII/SSIV ancestral gene found in Archaeplastida. Hence, both cyanobacteria and plants recruited similar enzymes independently to perform analogous tasks, further emphasizing the importance of convergent evolution in the appearance of starch from a preexisting glycogen metabolism network. © 2016 American Society of Plant Biologists. All Rights Reserved.

  18. Energy stores are not altered by long-term partial sleep deprivation in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Susan T Harbison

    2009-07-01

    Full Text Available Recent human studies reveal a widespread association between short sleep and obesity. Two hypotheses, which are not mutually exclusive, might explain this association. First, genetic factors that reduce endogenous sleep times might also impact energy stores, an assertion that we confirmed in a previous study. Second, metabolism may be altered by chronic partial sleep deprivation. Here we address the second assertion by measuring the impact of long-term partial sleep deprivation on energy stores using Drosophila as a model. We subjected flies to long-term partial sleep deprivation via two different methods: a mechanical stimulus and a light stimulus. We then measured whole-body triglycerides and glycogen, two important sources of energy for the fly, and compared them to un-stimulated controls. We also measured changes in energy stores in response to a random circadian clock shift. Sex and line-dependent alterations in glycogen and/or triglyceride levels occurred in response to the circadian clock shift and in flies subjected to a single night of sleep deprivation using light. Thus, consistent with previous studies, our findings suggest that acute sleep loss and changes to the circadian clock can alter metabolism. Significant changes in energy stores were also observed when flies were subjected to chronic sleep loss via the mechanical stimulus, although not the light stimulus. Interestingly, mechanical stimulation resulted in the same change in energy stores even when it was not associated with sleep deprivation, suggesting that the changes are caused by stress rather than sleep loss. These findings emphasize the importance of taking stress into account when evaluating the relationship between sleep loss and metabolism.

  19. Allegheny County Supermarkets & Convenience Stores

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Location information for all Supermarkets and Convenience Stores in Allegheny County was produced using the Allegheny County Fee and Permit Data for 2016.

  20. Information from the central stores

    CERN Multimedia

    GS Department

    2010-01-01

    All items sold in the CERN shop (Bldg. 33) are now available in the central stores (Bldg. 73) and can be purchased on-line via EDH “Material Request” or at the “Emergency Desk” of the stores on the ground floor of Bldg. 73. These items are visible in the CERN catalogue under the “SCEM” codes beginning with 92. Department of General Infrastructure Services (GS) GS-SEM Group

  1. Hemoglobin Function in Stored Blood.

    Science.gov (United States)

    1974-08-01

    States during 1973. Several advantages over ACA) are important. Blood stored in CPD maintains higher ./ levels of 2,3-DPG (2,3- diphosphoglycerate ) and a...survival and ATP levels in stored blood is explained by the several functions of ATP which are necessary for cell viability. However, ATP levels do...not correlate with oxygen affinity during storage. Levels of 2,3-DPG determine oxygen affinity and thus hemoglobin function. (12,13) When normal levels

  2. Metformin normalizes the structural changes in glycogen preceding prediabetes in mice overexpressing neuropeptide Y in noradrenergic neurons.

    Science.gov (United States)

    Ailanen, Liisa; Bezborodkina, Natalia N; Virtanen, Laura; Ruohonen, Suvi T; Malova, Anastasia V; Okovityi, Sergey V; Chistyakova, Elizaveta Y; Savontaus, Eriika

    2018-04-01

    Hepatic insulin resistance and increased gluconeogenesis are known therapeutic targets of metformin, but the role of hepatic glycogen in the pathogenesis of diabetes is less clear. Mouse model of neuropeptide Y (NPY) overexpression in noradrenergic neurons (OE-NPY D βH ) with a phenotype of late onset obesity, hepatosteatosis, and prediabetes was used to study early changes in glycogen structure and metabolism preceding prediabetes. Furthermore, the effect of the anti-hyperglycemic agent, metformin (300 mg/kg/day/4 weeks in drinking water), was assessed on changes in glycogen metabolism, body weight, fat mass, and glucose tolerance. Glycogen structure was characterized by cytofluorometric analysis in isolated hepatocytes and mRNA expression of key enzymes by qPCR. OE-NPY D βH mice displayed decreased labile glycogen fraction relative to stabile fraction (the intermediate form of glycogen) suggesting enhanced glycogen cycling. This was supported by decreased filling of glucose residues in the 10th outer tier of the glycogen molecule, which suggests accelerated glycogen phosphorylation. Metformin reduced fat mass gain in both genotypes, but glucose tolerance was improved mostly in wild-type mice. However, metformin inhibited glycogen accumulation and normalized the ratio between glycogen structures in OE-NPY D βH mice indicating decreased glycogen synthesis. Furthermore, the presence of glucose residues in the 11th tier together with decreased glycogen phosphorylase expression suggested inhibition of glycogen degradation. In conclusion, structural changes in glycogen of OE-NPY D βH mice point to increased glycogen metabolism, which may predispose them to prediabetes. Metformin treatment normalizes these changes and suppresses both glycogen synthesis and phosphorylation, which may contribute to its preventive effect on the onset of diabetes.

  3. A simulation based approach to optimize inventory replenishment with RAND algorithm: An extended study of corrected demand using Holt's method for textile industry

    Science.gov (United States)

    Morshed, Mohammad Sarwar; Kamal, Mostafa Mashnoon; Khan, Somaiya Islam

    2016-07-01

    Inventory has been a major concern in supply chain and numerous researches have been done lately on inventory control which brought forth a number of methods that efficiently manage inventory and related overheads by reducing cost of replenishment. This research is aimed towards providing a better replenishment policy in case of multi-product, single supplier situations for chemical raw materials of textile industries in Bangladesh. It is assumed that industries currently pursue individual replenishment system. The purpose is to find out the optimum ideal cycle time and individual replenishment cycle time of each product for replenishment that will cause lowest annual holding and ordering cost, and also find the optimum ordering quantity. In this paper indirect grouping strategy has been used. It is suggested that indirect grouping Strategy outperforms direct grouping strategy when major cost is high. An algorithm by Kaspi and Rosenblatt (1991) called RAND is exercised for its simplicity and ease of application. RAND provides an ideal cycle time (T) for replenishment and integer multiplier (ki) for individual items. Thus the replenishment cycle time for each product is found as T×ki. Firstly, based on data, a comparison between currently prevailing (individual) process and RAND is provided that uses the actual demands which presents 49% improvement in total cost of replenishment. Secondly, discrepancies in demand is corrected by using Holt's method. However, demands can only be forecasted one or two months into the future because of the demand pattern of the industry under consideration. Evidently, application of RAND with corrected demand display even greater improvement. The results of this study demonstrates that cost of replenishment can be significantly reduced by applying RAND algorithm and exponential smoothing models.

  4. CORPORATE REBRANDING OF GRAMEDIA STORE (CORPORATE REBRANDING DI GRAMEDIA STORE

    Directory of Open Access Journals (Sweden)

    Natasha Helena Kairupan

    2016-10-01

    Full Text Available Abstract. The purposes of this research are to determine the stages of analysis, planning, and evaluation of corporate rebranding process of Gramedia Book Store to be Gramedia Store to rise stakeholder’s awareness. The method used is descriptive qualitative with positivism paradigm. The technique of collecting data through in-depth interview, observation, and literature study. The result of this research showed the analysis stage by analyzing the market through insights and foresights, brand audit through SWOT analysis, and identifying opportunities. The planning stage is by determine the purpose of the planning process and then determine the target audience, consist of external and internal customer. The planning of external customer by renaming and change of corporate identity, and marketing planning using communication channel (above the line and below the line. The planning of internal customer by Brand Induction, training, inspiration briefing at store, and innovation competition. The evaluation of rebranding process of Gramedia Store is having a focus group discussion with customer, media monitoring, and presentation to BOD. Keywords : Process, Corporate Rebranding, Stakeholder Awareness, Corporate Identity, Gramedia Store Abstrak.Tujuan penelitian ini adalah untuk mengetahui bagaimana tahapan analisis, perencanaan, dan evaluasi proses corporate rebranding Gramedia Book Store menjadi Gramedia Store untuk meningkatkan stakeholder awareness. Pendekatan yang digunakan adalah kualitatif dengan paradigma positivisme dan jenis studi deksriptif. Teknik pengumpulan data yang dilakukan melalui wawancara mendalam, observasi, dan studi pustaka. Berdasarkan hasil penelitian, tahapan analisis dilakukan dengan menganalisis pasar melalui insights dan foresights, audit merek dengan analisis SWOT, dan mengidentifikasi peluang. Dalam tahapan perencanaan dengan menentukan tujuan kemudian menentukan target audiens, yaitu eksternal dan internal. Perencanaan

  5. Glycogen storage disease type II (Pompe disease in children

    Directory of Open Access Journals (Sweden)

    A. N. Semyachkina

    2014-01-01

    Full Text Available The paper gives the data available in the literature, which reflect the manifestations, diagnosis, and current treatments of the rare (orphan inherited disease glycogen storage disease type II or Pomp disease in children, as well as its classification. The infant form is shown to be most severe, resulting in death from cardiovascular or pulmonary failure generally within the first year of a child’s life. Emphasis is laid on major difficulties in the differential and true diagnosis of this severe disease. Much attention is given to the new pathogenetic treatment — genetically engineered enzyme replacement drug Myozyme®. The authors describe their clinical case of a child with the juvenile form of glycogen storage disease type II (late-onset Pompe disease. Particular emphasis is laid on the clinical symptoms of the disease and its diagnostic methods, among which the morphological analysis of a muscle biopsy specimen by light and electron microscopies, and enzyme and DNA diagnoses are of most importance. The proband was found to have significant lysosomal glycogen accumulation in the muscle biopsy specimen, reduced lymphocyte acid α-1,4-glucosidase activity to 4,2 nM/mg/h (normal value, 13,0—53,6 nM/mg/h, described in the HGMD missense mutation database from 1000 G>A p.Gly334er of the GAA in homozygous state, which verified the diagnosis of Pompe disease. 

  6. Compartmentation of glycogen metabolism revealed from 13C isotopologue distributions

    Directory of Open Access Journals (Sweden)

    Marin de Mas Igor

    2011-10-01

    Full Text Available Abstract Background Stable isotope tracers are used to assess metabolic flux profiles in living cells. The existing methods of measurement average out the isotopic isomer distribution in metabolites throughout the cell, whereas the knowledge of compartmental organization of analyzed pathways is crucial for the evaluation of true fluxes. That is why we accepted a challenge to create a software tool that allows deciphering the compartmentation of metabolites based on the analysis of average isotopic isomer distribution. Results The software Isodyn, which simulates the dynamics of isotopic isomer distribution in central metabolic pathways, was supplemented by algorithms facilitating the transition between various analyzed metabolic schemes, and by the tools for model discrimination. It simulated 13C isotope distributions in glucose, lactate, glutamate and glycogen, measured by mass spectrometry after incubation of hepatocytes in the presence of only labeled glucose or glucose and lactate together (with label either in glucose or lactate. The simulations assumed either a single intracellular hexose phosphate pool, or also channeling of hexose phosphates resulting in a different isotopic composition of glycogen. Model discrimination test was applied to check the consistency of both models with experimental data. Metabolic flux profiles, evaluated with the accepted model that assumes channeling, revealed the range of changes in metabolic fluxes in liver cells. Conclusions The analysis of compartmentation of metabolic networks based on the measured 13C distribution was included in Isodyn as a routine procedure. The advantage of this implementation is that, being a part of evaluation of metabolic fluxes, it does not require additional experiments to study metabolic compartmentation. The analysis of experimental data revealed that the distribution of measured 13C-labeled glucose metabolites is inconsistent with the idea of perfect mixing of hexose

  7. Glycogen as a biodegradable construction nanomaterial for in vivo use

    Czech Academy of Sciences Publication Activity Database

    Filippov, Sergey K.; Sedláček, Ondřej; Bogomolova, Anna; Vetrík, Miroslav; Jirák, D.; Kovář, J.; Kučka, Jan; Bals, S.; Turner, S.; Štěpánek, Petr; Hrubý, Martin

    2012-01-01

    Roč. 12, č. 12 (2012), s. 1731-1738 ISSN 1616-5187 R&D Projects: GA ČR GA202/09/2078; GA ČR GAP108/12/0640; GA ČR GAP208/10/1600; GA ČR GPP207/10/P054 Institutional research plan: CEZ:AV0Z40500505 Institutional support: RVO:61389013 Keywords : nanoparticles * in vivo imaging * glycogen Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.742, year: 2012

  8. Modified glycogen as construction material for functional biomimetic microfibers

    Czech Academy of Sciences Publication Activity Database

    Rabyk, Mariia; Hrubý, Martin; Vetrík, Miroslav; Kučka, Jan; Proks, Vladimír; Pařízek, Martin; Konefal, Rafal; Krist, Pavel; Chvátil, David; Bačáková, Lucie; Šlouf, Miroslav; Štěpánek, Petr

    2016-01-01

    Roč. 152, 5 November (2016), s. 271-279 ISSN 0144-8617 R&D Projects: GA ČR(CZ) GA13-08336S; GA MZd(CZ) NV15-25781A; GA MZd(CZ) NV15-32497A; GA MŠk(CZ) LM2015064 Institutional support: RVO:61389013 ; RVO:67985823 ; RVO:61389005 Keywords : glycogen * fibers * irradiation crosslinking Subject RIV: FR - Pharmacology ; Medidal Chemistry; FJ - Surgery incl. Transplants (FGU-C); BG - Nuclear, Atomic and Molecular Physics, Colliders (UJF-V) Impact factor: 4.811, year: 2016

  9. Limited contemporary gene flow and high self-replenishment drives peripheral isolation in an endemic coral reef fish.

    Science.gov (United States)

    van der Meer, Martin H; Horne, John B; Gardner, Michael G; Hobbs, Jean-Paul A; Pratchett, Morgan; van Herwerden, Lynne

    2013-06-01

    Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long-term persistence of these species following local extinction. This study explored population connectivity in the ecologically-specialized endemic three-striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self-replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self-replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self-replenishment (95%), and low contemporary abundance.

  10. The Optimal Replenishment Policy under Trade Credit Financing with Ramp Type Demand and Demand Dependent Production Rate

    Directory of Open Access Journals (Sweden)

    Juanjuan Qin

    2014-01-01

    Full Text Available This paper investigates the optimal replenishment policy for the retailer with the ramp type demand and demand dependent production rate involving the trade credit financing, which is not reported in the literatures. First, the two inventory models are developed under the above situation. Second, the algorithms are given to optimize the replenishment cycle time and the order quantity for the retailer. Finally, the numerical examples are carried out to illustrate the optimal solutions and the sensitivity analysis is performed. The results show that if the value of production rate is small, the retailer will lower the frequency of putting the orders to cut down the order cost; if the production rate is high, the demand dependent production rate has no effect on the optimal decisions. When the trade credit is less than the growth stage time, the retailer will shorten the replenishment cycle; when it is larger than the breakpoint of the demand, within the maturity stage of the products, the trade credit has no effect on the optimal order cycle and the optimal order quantity.

  11. Determination of the replenishment mechanism in the Los naranjos zone, Mexico, by the use of environmental isotopic techniques

    International Nuclear Information System (INIS)

    Payne, B.R.; Sainz O, I.

    1977-01-01

    The aquifers of the Los Naranjos Zone in the State of Veracruz have two principal sources of replenishment: the infiltration of the waters of the Rio Blanco along its channel. Granted that the eventual control of the waters of the Rio Blanco is capable of seriously affecting the exploitation of subterranean waters which is being implanted, it becomes necessary to learn its relative importance as a source of replenishment. As conventional techniques would not give a quick and sure answer to this matter, resort was had to isotopic techniques to solve the problem. In the rivers 27 samples of surface water were taken and 28 samples of subterranean water in wells, which were analyzed by I.A.E.A. with headquarters in Vienna. Interpretation of the data indicated, without room for doubt, that infiltrated rainwater represents 67% of the replenishment in the neighborhood of the Rio Blanco, 85% in the area's center, and 100% in the zones distant from the Rio Blanco. (author)

  12. Human acid alpha-glucosidase from rabbit milk has therapeutic effect in mice with glycogen storage disease type II

    NARCIS (Netherlands)

    A.G.A. Bijvoet (Agnes); A.J.J. Reuser (Arnold); H. van Hirtum (Hans); M.A. Kroos (Marian); E.H. van de Kamp; O. Schoneveld; P. Visser (Pim); J.P. Brakenhoff (Just); M. Weggeman (Miranda); E.J.J.M. van Corven (Emiel); A.T. van der Ploeg (Ans)

    1999-01-01

    textabstractPompe's disease or glycogen storage disease type II (GSDII) belongs to the family of inherited lysosomal storage diseases. The underlying deficiency of acid alpha-glucosidase leads in different degrees of severity to glycogen storage in heart, skeletal

  13. TruStore: Implementing a Trusted Store for Android

    OpenAIRE

    Yury, Zhauniarovich; Olga, Gadyatskaya; Bruno, Crispo

    2013-01-01

    In the Android ecosystem, the process of verifying the integrity of downloaded apps is left to the user. Different from other systems, e.g., Apple, App Store, Google does not provide any certified vetting process for the Android apps. This choice has a lot of advantages but it is also the open door to possible attacks as the recent one shown by Bluebox. To address this issue, we present how to enable the deployment of application certification service, we called TruStores, for the Android pla...

  14. Mitochondrial GSH replenishment as a potential therapeutic approach for Niemann Pick type C disease

    Directory of Open Access Journals (Sweden)

    Sandra Torres

    2017-04-01

    Full Text Available Niemann Pick type C (NPC disease is a progressive lysosomal storage disorder caused by mutations in genes encoding NPC1/NPC2 proteins, characterized by neurological defects, hepatosplenomegaly and premature death. While the primary biochemical feature of NPC disease is the intracellular accumulation of cholesterol and gangliosides, predominantly in endolysosomes, mitochondrial cholesterol accumulation has also been reported. As accumulation of cholesterol in mitochondria is known to impair the transport of GSH into mitochondria, resulting in mitochondrial GSH (mGSH depletion, we investigated the impact of mGSH recovery in NPC disease. We show that GSH ethyl ester (GSH-EE, but not N-acetylcysteine (NAC, restored the mGSH pool in liver and brain of Npc1-/- mice and in fibroblasts from NPC patients, while both GSH-EE and NAC increased total GSH levels. GSH-EE but not NAC increased the median survival and maximal life span of Npc1-/- mice. Moreover, intraperitoneal therapy with GSH-EE protected against oxidative stress and oxidant-induced cell death, restored calbindin levels in cerebellar Purkinje cells and reversed locomotor impairment in Npc1-/- mice. High-resolution respirometry analyses revealed that GSH-EE improved oxidative phosphorylation, coupled respiration and maximal electron transfer in cerebellum of Npc1-/- mice. Lipidomic analyses showed that GSH-EE treatment had not effect in the profile of most sphingolipids in liver and brain, except for some particular species in brain of Npc1-/- mice. These findings indicate that the specific replenishment of mGSH may be a potential promising therapy for NPC disease, worth exploring alone or in combination with other options.

  15. Physiological, biochemical and productive changes in sesame genotypes subjected to different rates of water replenishment

    Directory of Open Access Journals (Sweden)

    Maria S. R. Lima

    Full Text Available ABSTRACT The sesame crop has stood out due to the high nutritional content of its seeds, in addition to being able to be cultivated in the tropical and subtropical regions such as Northeast Brazil. Thus, it is necessary to identify the physiological, biochemical and productive changes related to the tolerance to stress. Objective of this study was to evaluate the physiological, biochemical and productive aspects of sesame genotypes as a function of different rates of water replenishment. The experiment was carried out at the Embrapa Cotton Experimental Unit, located in the municipality of Barbalha-CE, Brazil, under field conditions. The experiment was carried out in a randomized complete block design, with treatments in a factorial scheme (4 × 6, corresponding to four irrigation depths (40, 70, 100 and 130% ETo and six sesame genotypes (G1 = T3-EGSGO3; G2 = T7-EGSGO7; G3 = T5-EGSGO5; G4 = T2-EGSGO2; G5 = T6-EGSGO6; G6 = T4-EGSG04, with three replicates. Data corresponding to the following variables were collected: leaf area, photosynthetic pigments, relative water content in leaf, electrolyte leakage, catalase, peroxidase, yield and oil content. The genotypes did not differ statistically and there were differences in the variables between the water replacement rates. Increments in growth and, consequently, in production, enzymatic activity, oil content and maximum production potential were observed with water depths between 75 and 90% ETo. Contents of chlorophyll a and b, total chlorophyll and carotenoids, were increased with the application of 80% ETo.

  16. Partly ordered synthesis and degradation of glycogen in cultured rat myotubes

    DEFF Research Database (Denmark)

    Elsner, Peter; Quistorff, Bjørn; Hansen, Gert H

    2001-01-01

    The following questions concerning glycogen synthesis and degradation were examined in cultured rat myotubes. 1) Is synthesis and degradation of the individual glycogen molecule a strictly ordered process, with the last glucosyl unit incorporated into the molecule being the first to be released...

  17. Glycogen depletion and resynthesis during 14 days of chronic low-frequency stimulation of rabbit muscle

    DEFF Research Database (Denmark)

    Prats, C; Bernal, C; Cadefau, J A

    2002-01-01

    Electro-stimulation alters muscle metabolism and the extent of this change depends on application intensity and duration. The effect of 14 days of chronic electro-stimulation on glycogen turnover and on the regulation of glycogen synthase in fast-twitch muscle was studied. The results showed that...

  18. Effects of gamma-irradiation on the glycogen and lipid contents of the rat liver cells

    Energy Technology Data Exchange (ETDEWEB)

    Nahed, R H.A.; Al-Zahaby, Al-Ahmmady, S.; Sanad, S M.K.; Roushdy, H M

    1986-01-01

    Histochemical changes in the glycogen and lipid contents of the rat liver cells were studied at different intervals following whole body gamma-irradiation at the exposure dose level of 600 rads. The glycogen and lipid contents were significantly altered, the changes were time-dependent.

  19. Glycogen Supercompensation in the Rat Brain After Acute Hypoglycemia is Independent of Glucose Levels During Recovery.

    Science.gov (United States)

    Duarte, João M N; Morgenthaler, Florence D; Gruetter, Rolf

    2017-06-01

    Patients with diabetes display a progressive decay in the physiological counter-regulatory response to hypoglycemia, resulting in hypoglycemia unawareness. The mechanism through which the brain adapts to hypoglycemia may involve brain glycogen. We tested the hypothesis that brain glycogen supercompensation following hypoglycemia depends on blood glucose levels during recovery. Conscious rats were submitted to hypoglycemia of 2 mmol/L for 90 min and allowed to recover at different glycemia, controlled by means of i.v. glucose infusion. Brain glycogen concentration was elevated above control levels after 24 h of recovery in the cortex, hippocampus and striatum. This glycogen supercompensation was independent of blood glucose levels in the post-hypoglycemia period. In the absence of a preceding hypoglycemia insult, brain glycogen concentrations were unaltered after 24 h under hyperglycemia. In the hypothalamus, which controls peripheral glucose homeostasis, glycogen levels were unaltered. Overall, we conclude that post-hypoglycemia glycogen supercompensation occurs in several brain areas and its magnitude is independent of plasma glucose levels. By supporting brain metabolism during recurrent hypoglycemia periods, glycogen may have a role in the development of hypoglycemia unawareness.

  20. Is Type-2 Diabetes a Glycogen Storage Disease of Pancreatic β-Cells?

    Science.gov (United States)

    Ashcroft, Frances M; Rohm, Maria; Clark, Anne; Brereton, Melissa F

    2018-01-01

    Elevated plasma glucose leads to pancreatic β-cell dysfunction and death in type 2 diabetes. Glycogen accumulation, due to impaired metabolism, contributes to this ‘glucotoxicity’ via dysregulated biochemical pathways promoting β-cell dysfunction. Here, we review emerging data, and re-examine published findings, on the role of glycogen in β-cells in normoglycaemia and in diabetes. PMID:28683284

  1. Muscle Glycogen Content Modifies SR Ca2 + Release Rate in Elite Endurance Athletes

    DEFF Research Database (Denmark)

    Gejl, Kasper Degn; Hvid, Lars G; Frandsen, Ulrik

    2014-01-01

    The aim of the present study was to investigate the influence of muscle glycogen content on sarcoplasmic reticulum (SR) function and peak power output (Wpeak) in elite endurance athletes.......The aim of the present study was to investigate the influence of muscle glycogen content on sarcoplasmic reticulum (SR) function and peak power output (Wpeak) in elite endurance athletes....

  2. Changing shapes of glycogen-autophagy nexus in neurons: perspective from a rare epilepsy.

    Science.gov (United States)

    Singh, Pankaj Kumar; Singh, Sweta

    2015-01-01

    In brain, glycogen metabolism is predominantly restricted to astrocytes but it also indirectly supports neuronal functions. Increased accumulation of glycogen in neurons is mysteriously pathogenic triggering neurodegeneration as seen in "Lafora disease" (LD) and in other transgenic animal models of neuronal glycogen accumulation. LD is a fatal neurodegenerative disorder with excessive glycogen inclusions in neurons. Autophagy, a pathway for bulk degradation of obsolete cellular constituents also degrades metabolites like lipid and glycogen. Recently, defects in this pathway emerged as a plausible reason for glycogen accumulation in neurons in LD, although some contradictions prevail. Albeit surprising, a reciprocal regulation of autophagy by glycogen in neurons has also just been proposed. Notably, increasing evidences of interaction between proteins of autophagy and glycogen metabolism from diverse model systems indicate a conserved, dynamic, and regulatory cross-talk between these two pathways. Concerning these findings, we herein provide certain models for the molecular basis of this cross-talk and discuss its potential implication in the pathophysiology of LD.

  3. Contribution of glycogen in supporting axon conduction in the peripheral and central nervous systems: the role of lactate

    OpenAIRE

    Angus M Brown; Angus M Brown; Tom W Chambers; Timothy P Daly; Adam eHockley

    2014-01-01

    The role of glycogen in the central nervous system is intimately linked with the glycolytic pathway. Glycogen is synthesized from glucose, the primary substrate for glycolysis, and degraded to glucose-6-phosphate. The metabolic cost of shunting glucose via glycogen exceeds that of simple phosphorylation of glucose to glucose-6-phosphate by hexokinase; thus, there must be a metabolic advantage in utilizing this shunt pathway. The dogmatic view of glycogen as a storage depot persists, based on ...

  4. Energy Metabolism of the Brain, Including the Cooperation between Astrocytes and Neurons, Especially in the Context of Glycogen Metabolism

    OpenAIRE

    Falkowska, Anna; Gutowska, Izabela; Goschorska, Marta; Nowacki, Przemys?aw; Chlubek, Dariusz; Baranowska-Bosiacka, Irena

    2015-01-01

    Glycogen metabolism has important implications for the functioning of the brain, especially the cooperation between astrocytes and neurons. According to various research data, in a glycogen deficiency (for example during hypoglycemia) glycogen supplies are used to generate lactate, which is then transported to neighboring neurons. Likewise, during periods of intense activity of the nervous system, when the energy demand exceeds supply, astrocyte glycogen is immediately converted to lactate, s...

  5. Effect of carbon tetrachloride on glycogen metabolism in fasted and refed mice

    Energy Technology Data Exchange (ETDEWEB)

    Pushpendran, C K; Shenoy, B V; Eapen, J [Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.

    1977-11-01

    Hepatic glycogen was depleted rapidly in fasted mice treated with CCl/sub 4/. Glycogen breakdown was slow when CCl/sub 4/ was administered after 1 hr of refeeding. There was an initial increase and then a reduction in liver glycogen of mice refed for 2 hr prior to CCl/sub 4/ injection. The incorporation of glucose-U-/sup 14/C into glycogen was higher in mice which were refed before CCl/sub 4/ administration than in fasted mice treated with the hepatotoxin. The specific activity of lactate was higher in CCl/sub 4/ treated mice. The data suggested differences in glycogen metabolism of fasted and refed mice in response to CCl/sub 4/ treatment.

  6. Direct observation of glycogen synthesis in human muscle with 13C NMR

    International Nuclear Information System (INIS)

    Jue, T.; Rothman, D.L.; Shulman, G.I.; Tavitian, B.A.; DeFronzo, R.A.; Shulman, R.G.

    1989-01-01

    On the basis of previous indirect measurements, skeletal muscle has been implicated as the major site of glucose uptake and it has been suggested that muscle glycogen formation is the dominant pathway. However, direct measurements of the rates of glycogen synthesis have not been possible by previous techniques. The authors have developed 13 C NMR methods to measure directly the rate of human muscle glycogen formation from infused, isotopically labeled [1- 13 C]glucose. They show that under conditions of imposed hyperglycemia and hyperinsulinemia, a majority of the infused glucose was converted to muscle glycogen in a normal man. This directly shows that muscle is the major site of glucose disposal under these conditions, and provides quantitation of the glucose flux to muscle glycogen

  7. Dual regulation of muscle glycogen synthase during exercise by activation and compartmentalization

    DEFF Research Database (Denmark)

    Prats, Clara; Helge, Jørn W; Nordby, Pernille

    2009-01-01

    Glycogen synthase (GS) is considered the rate-limiting enzyme in glycogenesis but still today there is a lack of understanding on its regulation. We have previously shown phosphorylation-dependent GS intracellular redistribution at the start of glycogen re-synthesis in rabbit skeletal muscle (Prats......, C., Cadefau, J. A., Cussó, R., Qvortrup, K., Nielsen, J. N., Wojtaszewki, J. F., Wojtaszewki, J. F., Hardie, D. G., Stewart, G., Hansen, B. F., and Ploug, T. (2005) J. Biol. Chem. 280, 23165-23172). In the present study we investigate the regulation of human muscle GS activity by glycogen, exercise......, and insulin. Using immunocytochemistry we investigate the existence and relevance of GS intracellular compartmentalization during exercise and during glycogen re-synthesis. The results show that GS intrinsic activity is strongly dependent on glycogen levels and that such regulation involves associated...

  8. Method of storing solidification products

    International Nuclear Information System (INIS)

    Tani, Yutaro.

    1985-01-01

    Purpose: To enable to efficiently and satisfactorily cool and store solidification products of liquid wastes generated from the reactor spent fuel reprocessing process by a simple facility. Method: Liquid wastes generated from the reactor spent fuel reprocessing process are caused to flow from the upper opening to the inside of a spherical canistor. The opening of the spherical canistor is welded with a lid by a remote control and the liquid wastes are tightly sealed within the spherical canistor as glass solidification products. Spherical canistors having the solidification products tightly sealed therein are sent into and stored in a hopper by the remote control. Further, a blower is driven upon storing to suck cooling air from the cooling air intake port to the inside of the hopper to absorb the decay heat of radioactive materials in the solidification products and the air is discharged from the duct and through the stack to the atmosphere. (Kawakami, Y.)

  9. Glycogen storage disease type I: clinical and laboratory profile

    Directory of Open Access Journals (Sweden)

    Berenice L. Santos

    2014-12-01

    Full Text Available OBJECTIVES: To characterize the clinical, laboratory, and anthropometric profile of a sample of Brazilian patients with glycogen storage disease type I managed at an outpatient referral clinic for inborn errors of metabolism. METHODS: This was a cross-sectional outpatient study based on a convenience sampling strategy. Data on diagnosis, management, anthropometric parameters, and follow-up were assessed. RESULTS: Twenty-one patients were included (median age 10 years, range 1-25 years, all using uncooked cornstarch therapy. Median age at diagnosis was 7 months (range, 1-132 months, and 19 patients underwent liver biopsy for diagnostic confirmation. Overweight, short stature, hepatomegaly, and liver nodules were present in 16 of 21, four of 21, nine of 14, and three of 14 patients, respectively. A correlation was found between height-for-age and BMI-for-age Z-scores (r = 0.561; p = 0.008. CONCLUSIONS: Diagnosis of glycogen storage disease type I is delayed in Brazil. Most patients undergo liver biopsy for diagnostic confirmation, even though the combination of a characteristic clinical presentation and molecular methods can provide a definitive diagnosis in a less invasive manner. Obesity is a side effect of cornstarch therapy, and appears to be associated with growth in these patients.

  10. Inherent lipid metabolic dysfunction in glycogen storage disease IIIa.

    Science.gov (United States)

    Li, Xin-Hua; Gong, Qi-Ming; Ling, Yun; Huang, Chong; Yu, De-Min; Gu, Lei-Lei; Liao, Xiang-Wei; Zhang, Dong-Hua; Hu, Xi-Qi; Han, Yue; Kong, Xiao-Fei; Zhang, Xin-Xin

    2014-12-05

    We studied two patients from a nonconsanguineous family with life-long abnormal liver function, hepatomegaly and abnormal fatty acid profiles. Abnormal liver function, hypoglycemia and muscle weakness are observed in various genetic diseases, including medium-chain acyl-CoA dehydrogenase (MCAD) deficiency and glycogen storage diseases. The proband showed increased free fatty acids, mainly C8 and C10, resembling fatty acid oxidation disorder. However, no mutation was found in ACADM and ACADL gene. Sequencing of theamylo-alpha-1, 6-glucosidase, 4-alpha-glucanotransferase (AGL) gene showed that both patients were compound heterozygotes for c.118C > T (p.Gln40X) and c.753_756 del CAGA (p.Asp251Glufsx29), whereas their parents were each heterozygous for one of these mutations. The AGL protein was undetectable in EBV-B cells from the two patients. Transcriptome analysis demonstrated a significant different pattern of gene expression in both of patients’ cells, including genes involving in the PPAR signaling pathway, fatty acid biosynthesis, lipid synthesis and visceral fat deposition and metabolic syndrome. This unique gene expression pattern is probably due to the absence of AGL, which potentially accounts for the observed clinical phenotypes of hyperlipidemia and hepatocyte steatosis in glycogen storage disease type IIIa.

  11. Interleukin 6 stimulates hepatic glucose release from prelabeled glycogen pools

    International Nuclear Information System (INIS)

    Ritchie, D.G.

    1990-01-01

    Cytokines, derived from a wide variety of cell types, are now believed to initiate many of the physiological responses accompanying the inflammatory phase that follows either Gram-negative septicemia or thermal injury. Because hypoglycemia (after endotoxic challenge) and hyperglycemia (after thermal injury) represent well-characterized responses to these injuries, we sought to determine whether hepatic glycogen metabolism could be altered by specific cytokines. Cultured adult rat hepatocytes were prelabeled with [ 14 C]glucose for 24 h, a procedure that resulted in the labeling of hepatic glycogen pools that subsequently could be depleted (with concomitant [ 14 C]glucose release) by either glucagon or norepinephrine. After the addition of a highly concentrated human monocyte-conditioned medium (MCM) or various cytokines to these prelabeled cells, [ 14 C]glucose release was stimulated by MCM and recombinant human interleukin 6 (IL-6) but was not stimulated by other cytokines tested. Furthermore, only antisera to IL-6 were capable of reducing the glucose-releasing factor activity found in MCM. These data therefore suggest a novel glucoregulatory role for IL-6

  12. Enhanced Glycogen Storage of a Subcellular Hot Spot in Human Skeletal Muscle during Early Recovery from Eccentric Contractions

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Farup, Jean; Rahbek, Stine Klejs

    2015-01-01

    Unaccustomed eccentric exercise is accompanied by muscle damage and impaired glucose uptake and glycogen synthesis during subsequent recovery. Recently, it was shown that the role and regulation of glycogen in skeletal muscle are dependent on its subcellular localization, and that glycogen synthe...

  13. Method of storing fissile mateiral

    International Nuclear Information System (INIS)

    Onoshita, Toshio; Ishitobi, Masuhiro

    1989-01-01

    Upon storing nuclear fissile materials in a storing building, vessels packed with fissile materials are inserted into a containing chamber divided with partition walls comprising neutron absorbers and neutron moderators. Thus, released neutrons permeating the vessel are moderated by the neutron moderators and then absorbed by the neutron absorbers. Accordingly, the neutron absorbing effect by the neutron absorbers is improved, and irradiation of neutrons released from one of vessels to the other of vessels can be suppressed. Accordingly, it is possible to shorten the distance between the vessels in a contained state as much as possible, while securing the critical safety, to improve the containing density during storage. (T.M.)

  14. The nutritional status of Methanosarcina acetivorans regulates glycogen metabolism and gluconeogenesis and glycolysis fluxes.

    Science.gov (United States)

    Santiago-Martínez, Michel Geovanni; Encalada, Rusely; Lira-Silva, Elizabeth; Pineda, Erika; Gallardo-Pérez, Juan Carlos; Reyes-García, Marco Antonio; Saavedra, Emma; Moreno-Sánchez, Rafael; Marín-Hernández, Alvaro; Jasso-Chávez, Ricardo

    2016-05-01

    Gluconeogenesis is an essential pathway in methanogens because they are unable to use exogenous hexoses as carbon source for cell growth. With the aim of understanding the regulatory mechanisms of central carbon metabolism in Methanosarcina acetivorans, the present study investigated gene expression, the activities and metabolic regulation of key enzymes, metabolite contents and fluxes of gluconeogenesis, as well as glycolysis and glycogen synthesis/degradation pathways. Cells were grown with methanol as a carbon source. Key enzymes were kinetically characterized at physiological pH/temperature. Active consumption of methanol during exponential cell growth correlated with significant methanogenesis, gluconeogenic flux and steady glycogen synthesis. After methanol exhaustion, cells reached the stationary growth phase, which correlated with the rise in glycogen consumption and glycolytic flux, decreased methanogenesis, negligible acetate production and an absence of gluconeogenesis. Elevated activities of carbon monoxide dehydrogenase/acetyl-CoA synthetase complex and pyruvate: ferredoxin oxidoreductase suggested the generation of acetyl-CoA and pyruvate for glycogen synthesis. In the early stationary growth phase, the transcript contents and activities of pyruvate phosphate dikinase, fructose 1,6-bisphosphatase and glycogen synthase decreased, whereas those of glycogen phosphorylase, ADP-phosphofructokinase and pyruvate kinase increased. Therefore, glycogen and gluconeogenic metabolites were synthesized when an external carbon source was provided. Once such a carbon source became depleted, glycolysis and methanogenesis fed by glycogen degradation provided the ATP supply. Weak inhibition of key enzymes by metabolites suggested that the pathways evaluated were mainly transcriptionally regulated. Because glycogen metabolism and glycolysis/gluconeogenesis are not present in all methanogens, the overall data suggest that glycogen storage might represent an environmental

  15. Breastfeeding FAQs: Safely Storing Breast Milk

    Science.gov (United States)

    ... Search English Español Breastfeeding FAQs: Safely Storing Breast Milk KidsHealth / For Parents / Breastfeeding FAQs: Safely Storing Breast ... may have. How do I store my breast milk? You can freeze and/or refrigerate your pumped ( ...

  16. Model of the impact of parameters controlling replenishment in the bs (min-max) continuous review system on the actual inventory availibility

    OpenAIRE

    Stanisław Krzyżaniak

    2015-01-01

    Background: Due to random changes in demand, inventory management is still - despite the development of alternative goods flow management concepts - an important issue both in terms of costs of maintenance and replenishment as well as the level of service measured by inventory availability levels. There are a number of replenishment systems to be used in such conditions, but they are most often formed on the basis of two basic ones: a system based on the reorder point and based on periodic in...

  17. Store operations to maintain cache coherence

    Energy Technology Data Exchange (ETDEWEB)

    Evangelinos, Constantinos; Nair, Ravi; Ohmacht, Martin

    2017-08-01

    In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

  18. Store operations to maintain cache coherence

    Energy Technology Data Exchange (ETDEWEB)

    Evangelinos, Constantinos; Nair, Ravi; Ohmacht, Martin

    2017-09-12

    In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

  19. Stores, Weight and Inertial System Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility provides stores weight, center of gravity, and inertia measurements in support of weapon/aircraft compatibility testing. System provides store weight...

  20. Storing XML Documents in Databases

    NARCIS (Netherlands)

    A.R. Schmidt; S. Manegold (Stefan); M.L. Kersten (Martin); L.C. Rivero; J.H. Doorn; V.E. Ferraggine

    2005-01-01

    textabstractThe authors introduce concepts for loading large amounts of XML documents into databases where the documents are stored and maintained. The goal is to make XML databases as unobtrusive in multi-tier systems as possible and at the same time provide as many services defined by the XML

  1. Storing Peanuts in Grain Bags

    Science.gov (United States)

    A study was executed to determine the potential of storing farmers stock peanuts and shelled peanuts for crushing in hermetically sealed grain bags. The objectives of the study were to evaluate equipment for loading and unloading the grain bags, the capacity of the grain bags, and the changes in qu...

  2. Storing biomass in round bales

    Energy Technology Data Exchange (ETDEWEB)

    Summer, H.R.; Hellwig, R.E.; Monroe, G.E.

    1984-09-01

    Biomass fuels, in the form of crop residues, were stored outside in large round bales. The influence of rainfall on bale mass and the change in apparent average moisture content (A.A.M.C) was studied. Covering the bales with large sheets of polyethylene was found to be the most effective way of reducing moisture penetration.

  3. s larvae to stored cocoa

    African Journals Online (AJOL)

    olufunke oyedokun

    2015-04-22

    Apr 22, 2015 ... theobromine levels decrease, which in turn affects the colour, flavor (aroma) of the beans (Lagunes et al., 2007;. Rodriguez-Campos et al., 2011) and the organoleptic properties of the dried cocoa beans in store (Camu et al.,. 2008). Freshly harvested cocoa beans require fermentation for 5 - 7 days before ...

  4. Can mesophotic reefs replenish shallow reefs? Reduced coral reproductive performance casts a doubt.

    Science.gov (United States)

    Shlesinger, Tom; Grinblat, Mila; Rapuano, Hanna; Amit, Tal; Loya, Yossi

    2018-02-01

    Mesophotic coral ecosystems (i.e., deep coral reefs at 30-120 m depth) appear to be thriving while many shallow reefs in the world are declining. Amid efforts to understand and manage their decline, it was suggested that mesophotic reefs might serve as natural refuges and a possible source of propagules for the shallow reefs. However, our knowledge of how reproductive performance of corals alters with depth is sparse. Here, we present a comprehensive study of the reproductive phenology, fecundity, and abundance of seven reef-building conspecific corals in shallow and mesophotic habitats. Significant differences were found in the synchrony and timing of gametogenesis and spawning between shallow and mesophotic coral populations. Thus, mesophotic populations exhibited delayed or protracted spawning events, which led to spawning of the mesophotic colonies in large proportions at times where the shallow ones had long been depleted of reproductive material. All species investigated demonstrated a substantial reduction in fecundity and/or oocyte sizes at mesophotic depths (40-60 m). Two species (Seriatopora hystrix and Galaxea fascicularis) displayed a reduction in both fecundity and oocyte size at mesophotic depths. Turbinaria reniformis had only reduced fecundity and Acropora squarrosa and Acropora valida only reduced oocyte size. In Montipora verrucosa, reduced fecundity was found during one annual reproductive season while, in the following year, only reduced oocyte size was found. In contrast, reduced oocyte size in mesophotic populations of Acropora squarrosa was consistent along three studied years. One species, Acropora pharaonis, was found to be infertile at mesophotic depths along two studied years. This indicates that reproductive performance decreases with depth; and that although some species are capable of reproducing at mesophotic depths, their contribution to the replenishment of shallow reefs may be inconsequential. Reduced reproductive performance

  5. Activation of Basal Gluconeogenesis by Coactivator p300 Maintains Hepatic Glycogen Storage

    Science.gov (United States)

    Cao, Jia; Meng, Shumei; Ma, Anlin; Radovick, Sally; Wondisford, Fredric E.

    2013-01-01

    Because hepatic glycogenolysis maintains euglycemia during early fasting, proper hepatic glycogen synthesis in the fed/postprandial states is critical. It has been known for decades that gluconeogenesis is essential for hepatic glycogen synthesis; however, the molecular mechanism remains unknown. In this report, we show that depletion of hepatic p300 reduces glycogen synthesis, decreases hepatic glycogen storage, and leads to relative hypoglycemia. We previously reported that insulin suppressed gluconeogenesis by phosphorylating cAMP response element binding protein-binding protein (CBP) at S436 and disassembling the cAMP response element-binding protein-CBP complex. However, p300, which is closely related to CBP, lacks the corresponding S436 phosphorylation site found on CBP. In a phosphorylation-competent p300G422S knock-in mouse model, we found that mutant mice exhibited reduced hepatic glycogen content and produced significantly less glycogen in a tracer incorporation assay in the postprandial state. Our study demonstrates the important and unique role of p300 in glycogen synthesis through maintaining basal gluconeogenesis. PMID:23770612

  6. Abnormal glycogen chain length pattern, not hyperphosphorylation, is critical in Lafora disease.

    Science.gov (United States)

    Nitschke, Felix; Sullivan, Mitchell A; Wang, Peixiang; Zhao, Xiaochu; Chown, Erin E; Perri, Ami M; Israelian, Lori; Juana-López, Lucia; Bovolenta, Paola; Rodríguez de Córdoba, Santiago; Steup, Martin; Minassian, Berge A

    2017-07-01

    Lafora disease (LD) is a fatal progressive epilepsy essentially caused by loss-of-function mutations in the glycogen phosphatase laforin or the ubiquitin E3 ligase malin. Glycogen in LD is hyperphosphorylated and poorly hydrosoluble. It precipitates and accumulates into neurotoxic Lafora bodies (LBs). The leading LD hypothesis that hyperphosphorylation causes the insolubility was recently challenged by the observation that phosphatase-inactive laforin rescues the laforin-deficient LD mouse model, apparently through correction of a general autophagy impairment. We were for the first time able to quantify brain glycogen phosphate. We also measured glycogen content and chain lengths, LBs, and autophagy markers in several laforin- or malin-deficient mouse lines expressing phosphatase-inactive laforin. We find that: (i) in laforin-deficient mice, phosphatase-inactive laforin corrects glycogen chain lengths, and not hyperphosphorylation, which leads to correction of glycogen amounts and prevention of LBs; (ii) in malin-deficient mice, phosphatase-inactive laforin confers no correction; (iii) general impairment of autophagy is not necessary in LD We conclude that laforin's principle function is to control glycogen chain lengths, in a malin-dependent fashion, and that loss of this control underlies LD. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  7. In vivo Magnetic Resonance Spectroscopy of cerebral glycogen metabolism in animals and humans

    Science.gov (United States)

    Khowaja, Ameer; Choi, In-Young; Seaquist, Elizabeth R.; Öz, Gülin

    2015-01-01

    Glycogen serves as an important energy reservoir in the human body. Despite the abundance of glycogen in the liver and skeletal muscles, its concentration in the brain is relatively low, hence its significance has been questioned. A major challenge in studying brain glycogen metabolism has been the lack of availability of non-invasive techniques for quantification of brain glycogen in vivo. Invasive methods for brain glycogen quantification such as post mortem extraction following high energy microwave irradiation are not applicable in the human brain. With the advent of 13C Magnetic Resonance Spectroscopy (MRS), it has been possible to measure brain glycogen concentrations and turnover in physiological conditions, as well as under the influence of stressors such as hypoglycemia and visual stimulation. This review presents an overview of the principles of the 13C MRS methodology and its applications in both animals and humans to further our understanding of glycogen metabolism under normal physiological and pathophysiological conditions such as hypoglycemia unawareness. PMID:24676563

  8. Technical note: A method for isolating glycogen granules from ruminal protozoa for further characterization.

    Science.gov (United States)

    Hall, Mary Beth

    2016-03-01

    Evaluation of physical, chemical, and enzymatic hydrolysis characteristics of protozoal glycogen is best performed on a pure substrate to avoid interference from other cell components. A method for isolating protozoal glycogen granules without use of detergents or other potentially contaminating chemicals was developed. Rumen inoculum was incubated anerobically in vitro with glucose. Glycogen-laden protozoa produced in the fermentation, primarily isotrichids, were allowed to sediment in a separatory funnel and were dispensed. The protozoa were processed through repeated centrifugations and sonication to isolate glycogen granules largely free of feed and cellular debris. The final water-insoluble lyophilized product analyzed as 98.3% α-glucan with very rare starch granules and 1.9% protein. Observed losses of glycogen granules during the clean-up process indicate that this procedure should not be used for quantitative assessment of protozoal glycogen from fermentations. Further optimization of this procedure to enhance the amount of glycogen obtained per fermentation may be possible. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. [3H] glycogen hydrolysis in brain slices: responses to meurotransmitters and modulation of noradrenaline receptors

    International Nuclear Information System (INIS)

    Quach, T.T.; Rose, C.; Schwartz, J.C.

    1978-01-01

    Different agents have been investigated for their effects on [ 3 H] glycogen synthesized in mouse cortical slices. Of these noradrenaline, serotonin and histamine induced clear concentration-dependent glycogenesis. [ 3 H] glycogen hydrolysis induced by noradrenaline appears to be mediated by beta-adrenergic receptors because it is completely prevented by timolol, while phentolamine is ineffective. It seems to involve cyclic AMP because it is potentiated in the presence of isobutylmethylxanthine; in addition dibutyryl cyclic AMP (but not dibutyryl cyclic GMP) promotes glycogenolysis. Lower concentrations of noradrenaline were necessary for [ 3 H] glycogen hydrolysis (ECsub(50) 0.5μM) than for stimulation of cyclic AMP accumulation (ECsub(50) = 8μM). After subchronic reserpine treatment the concentration-response curve to noradrenaline was significantly shifted to the left (ECsub(50) = 0.09 +- 0.02 μM as compared with 0.49 +- 0.08μM in saline-pretreated mice) without modifications of either the basal [ 3 H] glycogen level, maximal glycogenolytic effect, or the dibutyryl cAMP-induced glycogenolytic response. In addition to noradrenaline, clear concentration-dependent [ 3 H] glycogen hydrolysis was observed in the presence of histamine or serotonin. In contrast to the partial [ 3 H] glycogen hydrolysis elicited by these biogenic amines, depolarization of the slices by 50 mM K + provoked a nearly total [ 3 H] glycogen hydrolysis. (author)

  10. Chronic corticosterone exposure reduces hippocampal glycogen level and induces depression-like behavior in mice.

    Science.gov (United States)

    Zhang, Hui-yu; Zhao, Yu-nan; Wang, Zhong-li; Huang, Yu-fang

    2015-01-01

    Long-term exposure to stress or high glucocorticoid levels leads to depression-like behavior in rodents; however, the cause remains unknown. Increasing evidence shows that astrocytes, the most abundant cells in the central nervous system (CNS), are important to the nervous system. Astrocytes nourish and protect the neurons, and serve as glycogen repositories for the brain. The metabolic process of glycogen, which is closely linked to neuronal activity, can supply sufficient energy substrates for neurons. The research team probed into the effects of chronic corticosterone (CORT) exposure on the glycogen level of astrocytes in the hippocampal tissues of male C57BL/6N mice in this study. The results showed that chronic CORT injection reduced hippocampal neurofilament light protein (NF-L) and synaptophysin (SYP) levels, induced depression-like behavior in male mice, reduced hippocampal glycogen level and glycogen synthase activity, and increased glycogen phosphorylase activity. The results suggested that the reduction of the hippocampal glycogen level may be the mechanism by which chronic CORT treatment damages hippocampal neurons and induces depression-like behavior in male mice.

  11. Effect of glycogen synthase overexpression on insulin-stimulated muscle glucose uptake and storage.

    Science.gov (United States)

    Fogt, Donovan L; Pan, Shujia; Lee, Sukho; Ding, Zhenping; Scrimgeour, Angus; Lawrence, John C; Ivy, John L

    2004-03-01

    Insulin-stimulated muscle glucose uptake is inversely associated with the muscle glycogen concentration. To investigate whether this association is a cause and effect relationship, we compared insulin-stimulated muscle glucose uptake in noncontracted and postcontracted muscle of GSL3-transgenic and wild-type mice. GSL3-transgenic mice overexpress a constitutively active form of glycogen synthase, which results in an abundant storage of muscle glycogen. Muscle contraction was elicited by in situ electrical stimulation of the sciatic nerve. Right gastrocnemii from GSL3-transgenic and wild-type mice were subjected to 30 min of electrical stimulation followed by hindlimb perfusion of both hindlimbs. Thirty minutes of contraction significantly reduced muscle glycogen concentration in wild-type (49%) and transgenic (27%) mice, although transgenic mice retained 168.8 +/- 20.5 micromol/g glycogen compared with 17.7 +/- 2.6 micromol/g glycogen for wild-type mice. Muscle of transgenic and wild-type mice demonstrated similar pre- (3.6 +/- 0.3 and 3.9 +/- 0.6 micromol.g(-1).h(-1) for transgenic and wild-type, respectively) and postcontraction (7.9 +/- 0.4 and 7.0 +/- 0.4 micromol.g(-1).h(-1) for transgenic and wild-type, respectively) insulin-stimulated glucose uptakes. However, the [14C]glucose incorporated into glycogen was greater in noncontracted (151%) and postcontracted (157%) transgenic muscle vs. muscle of corresponding wild-type mice. These results indicate that glycogen synthase activity is not rate limiting for insulin-stimulated glucose uptake in skeletal muscle and that the inverse relationship between muscle glycogen and insulin-stimulated glucose uptake is an association, not a cause and effect relationship.

  12. Pluralistic roles for glycogen in the central and peripheral nervous systems.

    Science.gov (United States)

    Fryer, Kirsty L; Brown, Angus M

    2015-02-01

    Glycogen is present in the mammalian nervous system, but at concentrations of up to one hundred times lower than those found in liver and skeletal muscle. This relatively low concentration has resulted in neglect of assigning a role(s) for brain glycogen, but in the last 15 years enormous progress has been made in revealing the multifaceted roles that glycogen plays in the mammalian nervous system. Initial studies highlighted a role for glycogen in supporting neural elements (neurons and axons) during aglycemia, where glycogen supplied supplementary energy substrate in the form of lactate to fuel neural oxidative metabolism. The appropriate enzymes and membrane bound transporters have been localized to cellular locations consistent with astrocyte to neuron energy substrate shuttling. A role for glycogen in supporting the induction of long term potential (LTP) in the hippocampus has recently been described, where glycogen is metabolized to lactate and shuttled to neurons via the extracellular space by monocarboxylate transporters, where it plays an integral role in the induction process of LTP. This is the first time that glycogen has been assigned a role in a distinct, complex physiological brain function, where the lack of glycogen, in the presence of normoglycemia, results in disturbance of the function. The signalling pathway that alerts astrocytes to increased neuronal activity has been recently described, highlighting a pivotal role for increased extracellular potassium ([K(+)]o) that routinely accompanies increased neural activity. An astrocyte membrane bound bicarbonate transporter is activated by the [K(+)]o, the resulting increase in intracellular bicarbonate alkalizing the cell's interior and activating soluble adenyl cyclase (sAC). The sAC promotes glycogenolysis via increases in cyclic AMP, ultimately producing lactate, which is shuttled out of the astrocyte and presumably taken up by neurons from the extracellular space.

  13. A glycogene mutation map for discovery of diseases of glycosylation

    DEFF Research Database (Denmark)

    Hansen, Lars; Lind-Thomsen, Allan; Joshi, Hiren J

    2015-01-01

    homologous families. However, Genome-Wide-Association Studies (GWAS) have identified such isoenzyme genes as candidates for different diseases, but validation is not straightforward without biomarkers. Large-scale whole exome sequencing (WES) provides access to mutations in e.g. glycosyltransferase genes...... in populations, which can be used to predict and/or analyze functional deleterious mutations. Here, we constructed a draft of a Functional Mutational Map of glycogenes, GlyMAP, from WES of a rather homogenous population of 2,000 Danes. We catalogued all missense mutations and used prediction algorithms, manual...... inspection, and in case of CAZy family GT27 experimental analysis of mutations to map deleterious mutations. GlyMAP provides a first global view of the genetic stability of the glycogenome and should serve as a tool for discovery of novel CDGs....

  14. Pulmonary Arterial Hypertension in Glycogen Storage Disease Type I

    Directory of Open Access Journals (Sweden)

    Rachel D. Torok MD

    2017-05-01

    Full Text Available Pulmonary arterial hypertension (PAH is a rare and highly fatal disease that has been reported in 8 patients with glycogen storage disease type I (GSDI. We describe an additional case of an acute presentation of PAH in a 14-year-old patient with GSDI, which was successfully treated with inhaled nitric oxide and sildenafil. We investigated the incidence of PAH in 28 patients with GSDI on routine echocardiography and found no evidence of PAH and no significant cardiac abnormalities. This study highlights that PAH is a rare disease overall, but our case report and those previously described suggest an increased incidence in patients with GSDI. Should cardiopulmonary symptoms develop, clinicians caring for patients with GSDI should have a high degree of suspicion for acute PAH and recognize that prompt intervention can lead to survival in this otherwise highly fatal disease.

  15. Model/School Store Management Guide.

    Science.gov (United States)

    North Dakota State Board for Vocational Education, Bismarck.

    This teacher-coordinator manual assists in planning, organizing, directing, and evaluating student learning experiences associated with either a model store, school store, or combination. (A model store in a marketing laboratory simulates marketing functions; the school store markets merchandise to fellow students, faculty, and/or the public.)…

  16. Caffeine-Induced Ca2+ Oscillations in Type I Horizontal Cells of the Carp Retina and the Contribution of the Store-Operated Ca2+ Entry Pathway

    Science.gov (United States)

    Lv, Ting; Gong, Hai-Qing; Liang, Pei-Ji

    2014-01-01

    The mechanisms of release, depletion, and refilling of endoplasmic reticulum (ER) Ca2+ were investigated in type I horizontal cells of the carp retina using a fluo-3-based Ca2+ imaging technique. Exogenous application of caffeine, a ryanodine receptor agonist, induced oscillatory intracellular free Ca2+ concentration ([Ca2+]i) responses in a duration- and concentration-dependent manner. In Ca2+-free Ringer’s solution, [Ca2+]i transients could also be induced by a brief caffeine application, whereas subsequent caffeine application induced no [Ca2+]i increase, which implied that extracellular Ca2+ was required for ER refilling, confirming the necessity of a Ca2+ influx pathway for ER refilling. Depletion of ER Ca2+ by thapsigargin triggered a Ca2+ influx which could be blocked by the store-operated channel inhibitor 2-APB, which proved the existence of the store-operated Ca2+ entry pathway. Taken together, these results suggested that after being depleted by caffeine, the ER was replenished by Ca2+ influx via store-operated channels. These results reveal the fine modulation of ER Ca2+ signaling, and the activation of the store-operated Ca2+ entry pathway guarantees the replenishment of the ER so that the cell can be ready for response to the subsequent stimulus. PMID:24918937

  17. Glycogen storage disease type III: modified Atkins diet improves myopathy.

    Science.gov (United States)

    Mayorandan, Sebene; Meyer, Uta; Hartmann, Hans; Das, Anibh Martin

    2014-11-28

    Frequent feeds with carbohydrate-rich meals or continuous enteral feeding has been the therapy of choice in glycogen storage disease (Glycogenosis) type III. Recent guidelines on diagnosis and management recommend frequent feedings with high complex carbohydrates or cornstarch avoiding fasting in children, while in adults a low-carb-high-protein-diet is recommended. While this regimen can prevent hypoglycaemia in children it does not improve skeletal and heart muscle function, which are compromised in patients with glycogenosis IIIa. Administration of carbohydrates may elicit reactive hyperinsulinism, resulting in suppression of lipolysis, ketogenesis, gluconeogenesis, and activation of glycogen synthesis. Thus, heart and skeletal muscle are depleted of energy substrates. Modified Atkins diet leads to increased blood levels of ketone bodies and fatty acids. We hypothesize that this health care intervention improves the energetic balance of muscles. We treated 2 boys with glycogenosis IIIa aged 9 and 11 years with a modified Atkins diet (10 g carbohydrate per day, protein and fatty acids ad libitum) over a period of 32 and 26 months, respectively. In both patients, creatine kinase levels in blood dropped in response to Atkins diet. When diet was withdrawn in one of the patients he complained of chest pain, reduced physical strength and creatine kinase levels rapidly increased. This was reversed when Atkins diet was reintroduced. One patient suffered from severe cardiomyopathy which significantly improved under diet. Patients with glycogenosis IIIa benefit from an improved energetic state of heart and skeletal muscle by introduction of Atkins diet both on a biochemical and clinical level. Apart from transient hypoglycaemia no serious adverse effects were observed.

  18. Storing XML Documents in Databases

    OpenAIRE

    Schmidt, A.R.; Manegold, Stefan; Kersten, Martin; Rivero, L.C.; Doorn, J.H.; Ferraggine, V.E.

    2005-01-01

    textabstractThe authors introduce concepts for loading large amounts of XML documents into databases where the documents are stored and maintained. The goal is to make XML databases as unobtrusive in multi-tier systems as possible and at the same time provide as many services defined by the XML standards as possible. The ubiquity of XML has sparked great interest in deploying concepts known from Relational Database Management Systems such as declarative query languages, transactions, indexes ...

  19. Method of storing radioactive wastes

    International Nuclear Information System (INIS)

    Adachi, Toshio; Hiratake, Susumu.

    1980-01-01

    Purpose: To reduce the radiation doses externally irradiated from treated radioactive waste and also reduce the separation of radioactive nuclide due to external environmental factors such as air, water or the like. Method: Radioactive waste adhered with radioactive nuclide to solid material is molten to mix and submerge the radioactive nuclide adhered to the surface of the solid material into molten material. Then, the radioactive nuclide thus mixed is solidified to store the waste in solidified state. (Aizawa, K.)

  20. Specialty Store and Multi-Brand Store loyalty: An Indian consumer perspective

    Directory of Open Access Journals (Sweden)

    Sarabjot Singh

    2013-12-01

    Full Text Available In the competitive era of retailing, retailers need to understand the importance of store format preferences. The study aimed to understand consumer store loyalty; in-depth interview was conducted to examine consumer store loyalty antecedents for two retail formats: specialty stores and multi brand stores. The study conceptualizes store loyalty factors like program loyalty, trust and brand commitment. Trust and brand commitment act as mediating factors between store image and store loyalty formats, and also between brand image and store loyalty formats. The findings highlight how consumer store loyalty preference differ for these two formats.

  1. Understanding Retailers’ Acceptance of Virtual Stores

    OpenAIRE

    Irene Y.L. Chen

    2010-01-01

    The acceptance of e-commerce among consumers has stimulated the rise of virtual stores. Increasing traditional retailers or people who do not have sufficient capital for maintaining a brick-and-mortar store have considered using virtual stores to reach global market. In the e-commerce literature, there has been rich research evidence concerning consumers’ acceptance of virtual stores. However, rigorous academic research on retailers’ acceptance of virtual stores is relatively scarce today. Th...

  2. Glycogen distribution in adult and geriatric mice brains

    KAUST Repository

    Alrabeh, Rana

    2017-01-01

    Astrocytes, the most abundant glial cell type in the brain, undergo a number of roles in brain physiology; among them, the energetic support of neurons is the best characterized. Contained within astrocytes is the brain’s obligate energy store

  3. Regulation of Energy Stores and Feeding by Neuronal and Peripheral CREB Activity in Drosophila

    Science.gov (United States)

    Iijima, Koichi; Zhao, LiJuan; Shenton, Christopher; Iijima-Ando, Kanae

    2009-01-01

    The cAMP-responsive transcription factor CREB functions in adipose tissue and liver to regulate glycogen and lipid metabolism in mammals. While Drosophila has a homolog of mammalian CREB, dCREB2, its role in energy metabolism is not fully understood. Using tissue-specific expression of a dominant-negative form of CREB (DN-CREB), we have examined the effect of blocking CREB activity in neurons and in the fat body, the primary energy storage depot with functions of adipose tissue and the liver in flies, on energy balance, stress resistance and feeding behavior. We found that disruption of CREB function in neurons reduced glycogen and lipid stores and increased sensitivity to starvation. Expression of DN-CREB in the fat body also reduced glycogen levels, while it did not affect starvation sensitivity, presumably due to increased lipid levels in these flies. Interestingly, blocking CREB activity in the fat body increased food intake. These flies did not show a significant change in overall body size, suggesting that disruption of CREB activity in the fat body caused an obese-like phenotype. Using a transgenic CRE-luciferase reporter, we further demonstrated that disruption of the adipokinetic hormone receptor, which is functionally related to mammalian glucagon and β-adrenergic signaling, in the fat body reduced CRE-mediated transcription in flies. This study demonstrates that CREB activity in either neuronal or peripheral tissues regulates energy balance in Drosophila, and that the key signaling pathway regulating CREB activity in peripheral tissue is evolutionarily conserved. PMID:20041126

  4. Genetic connectivity and self-replenishment of inshore and offshore populations of the endemic anemonefish, Amphiprion latezonatus

    KAUST Repository

    Steinberg, Rosemary

    2016-02-19

    Globally, marine species are under increasing pressure from human activities, including ocean warming, acidification, pollution, and overfishing. Species most vulnerable to these pressures tend to be ecological specialists that have low abundance and small distribution ranges (endemics). Marine endemics often exist as meta-populations distributed among few isolated locations. Determining genetic connectivity among these locations is essential to understanding the recovery potential of endemics after local extinction events. This study examined connectivity in the endemic anemonefish, Amphiprion latezonatus, a habitat specialist with low abundance at most locations. Evolutionary and contemporary migration, genetic diversity, and self-replenishment among the four main locations (Sunshine Coast, North Solitary Island, Lord Howe Island, and Norfolk Island) that comprise the entire A. latezonatus geographic range were assessed using mtDNA and microsatellite markers. Though historical gene flow inferred from mtDNA appeared high, population genetic differentiation was evident and contemporary gene flow inferred from microsatellites was limited, alongside very high (≥89 %) self-replenishment at all locations. Together, these data suggest prolonged recovery times following severe population decline (or extirpation) and indicate a need to protect this species at all locations, particularly Norfolk Island and Sunshine Coast where marine protected areas are lacking.

  5. Effect of medium replenishment or composition on [3H] thymidine incorporation in uv-irradiated CHO-K1 cells

    International Nuclear Information System (INIS)

    Newman, C.N.; Miller, J.H.

    1985-03-01

    Because culture medium contains uv-absorbing material, it is usually removed just before uv-irradiation of tissue culture monolayers. However, medium removal and replenishment with fresh medium alone (sham-irradiation) causes up to a 10-fold reduction in the rate of [ 3 H]TdR incorporation in CHO-K1 cells which persists for several hours. This reduction, which is much smaller ( 3 H]TdR pulse-label in conditioned (spent) and in fresh medium; TdR in the former is converted by cells to thymine. When responses of uv-irradiated cells are normalized to responses of corresponding sham-irradiated cultures, considerable variation is observed in replicate experiments because fresh medium appears to induce transient metabolic imbalances in irradiated cells which are not readily controlled. This problem can, in part, be circumvented by replenishing treated cultures with the original spent medium; however, the presence of CdR in the growth medium still causes an anomalous 2-3-fold greater uv-induced reduction in [ 3 H]TdR incorporation than is observed in the absence of CdR. 17 refs., 3 figs., 1 tab

  6. Adiponectin levels correlate with the severity of hypertriglyceridaemia in glycogen storage disease Ia

    NARCIS (Netherlands)

    Bandsma, R. H. J.; Smit, G. P. A.; Reijngoud, D. -J.; Kuipers, F.

    2009-01-01

    Glycogen storage disease type Ia (GSD Ia) is characterized by severe hypercholesterolaemia and hypertriglyceridaemia. Little is known about the aetiology of the hyperlipidaemia in GSD Ia. Adipokines play an important regulatory role in lipid metabolism. We investigated whether adipokine

  7. Glycogen synthesis in liver and skeletal muscle after exercise: participation of the gluconeogenic pathway

    International Nuclear Information System (INIS)

    Johnson, J.L.

    1986-01-01

    Hepatic glycogenesis occurs by both the uptake of plasma glucose (direct pathway) as well as from gluconeogenesis (indirect pathway). In vitro studies suggest that skeletal muscle can also synthesize glycogen from lactate. The purpose of the present studies was to assess the contribution of the indirect pathway to liver and muscle glycogen synthesis after exercise with various substrata infusions. The authors hypothesis was the contribution of the indirect pathway of hepatic glycogenesis would increase after exercise. To this end, fasted rats were depleted of glycogen by exhaustive exercise; a second group of fasted rats remained rested. Both groups were then infused intravenously with glucose containing tracer quantities of [6- 3 H] and [U- 14 C] glucose for 4 hrs. The ensuing hyperglycemic response was exaggerated in post-exercised rats; whereas, plasma lactate levels were lower than those of nonexercised rats. The percent of hepatic glycogen synthesized from gluconeogenic precursors did not differ between exercised (39%) and nonexercised (36%) rats

  8. Identification and Structural Basis of Binding to Host Lung Glycogen by Streptococcal Virulence Factors

    Energy Technology Data Exchange (ETDEWEB)

    Lammerts van Bueren,A.; Higgins, M.; Wang, D.; Burke, R.; Boraston, A.

    2007-01-01

    The ability of pathogenic bacteria to recognize host glycans is often essential to their virulence. Here we report structure-function studies of previously uncharacterized glycogen-binding modules in the surface-anchored pullulanases from Streptococcus pneumoniae (SpuA) and Streptococcus pyogenes (PulA). Multivalent binding to glycogen leads to a strong interaction with alveolar type II cells in mouse lung tissue. X-ray crystal structures of the binding modules reveal a novel fusion of tandem modules into single, bivalent functional domains. In addition to indicating a structural basis for multivalent attachment, the structure of the SpuA modules in complex with carbohydrate provides insight into the molecular basis for glycogen specificity. This report provides the first evidence that intracellular lung glycogen may be a novel target of pathogenic streptococci and thus provides a rationale for the identification of the streptococcal {alpha}-glucan-metabolizing machinery as virulence factors.

  9. The glucose-galactose paradox in neonatal murine hepatic glycogen synthesis

    International Nuclear Information System (INIS)

    Kunst, C.; Kliegman, R.; Trindade, C.

    1989-01-01

    In adults glucose incorporation to glycogen is indirect after recycling from lactate. In neonates galactose entry to glycogen exceeds that for glucose, but the pathway is unknown. The pathway of hexose incorporation to glycogen was studied in 5-7-day-old rats and 6-h-old rats injected intraperitoneally (IP) with either double-labeled [6-3H]glucose (nonrecycling), [U-14C]glucose (recycling), or [6-3H]glucose and [U-14C]galactose in saline. In another group of pups, 1 g/kg of glucose or galactose was administered in addition to tracers to determine glycemia and net glycogen synthesis between 15 and 180 min after injection. Blood glucose increased from 3.4 +/- 0.4 to 8.5 +/- 1.5 mM in 5-7-day-old pups in response to IP glucose; there was no glycemic response to galactose, although galactose levels increased from 0.5 to 6.3 mM at 15 min. Hepatic glycogen increased after IP glucose from 14 +/- 2 at 15 min to 30 +/- 3 at 120 min (P less than 0.01), whereas after IP galactose glycogen was 44 +/- 6 mumol/g at 120 min (P less than 0.05). After IP glucose, 3H and 14C disintegration per minute in glycogen increased slowly with 14C exceeding 3H at 120 and 180 min. In contrast IP [14C]galactose resulted in a much greater peak of 14C incorporation into glycogen. The ratio of 3H to 14C in glycogen relative to the injectate after IP glucose decreased from 0.69 +/- 0.12 to 0.36 +/- 0.03 (P less than 0.01) between 15 to 180 min, whereas the ratio after galactose was 0.20 +/- 0.007 to 0.15 +/- 0.02 at these times. The 6-h-old pups also demonstrated augmented incorporation of [14C]galactose in glycogen relative to [3H-14C]glucose. In contrast to 5-7-day-old pups there was no evidence of glucose recycling in 6-h-old pups. In conclusion galactose entry into glycogen exceeds that for glucose and is not dependent on recycling

  10. Contribution of glycogen in supporting axon conduction in the peripheral and central nervous systems: the role of lactate

    Directory of Open Access Journals (Sweden)

    Angus M Brown

    2014-11-01

    Full Text Available The role of glycogen in the central nervous system is intimately linked with the glycolytic pathway. Glycogen is synthesized from glucose, the primary substrate for glycolysis, and degraded to glucose-6-phosphate. The metabolic cost of shunting glucose via glycogen exceeds that of simple phosphorylation of glucose to glucose-6-phosphate by hexokinase; thus, there must be a metabolic advantage in utilizing this shunt pathway. The dogmatic view of glycogen as a storage depot persists, based on initial descriptions of glycogen supporting neural function in the face of aglycemia. The variable latency to conduction failure, dependent upon tissue glycogen levels, provided convincing evidence of the role played by glycogen in supporting neural function. Glycogen is located predominantly in astrocytes in the central nervous system, thus for glycogen to benefit neural elements, intercellular metabolic communication must exist in the form of astrocyte to neuron substrate transfer. Experimental evidence supports a model where glycogen is metabolized to lactate in astrocytes, with cellular expression of monocarboxylate transporters and enzymes appropriately located for lactate shuttling between astrocytes and neural elements, where lactate acts as a substrate for oxidative metabolism. Biosensor recordings have demonstrated a significant steady concentration of lactate present on the periphery of both central white matter and peripheral nerve under unstimulated baseline conditions, indicating continuous cellular efflux of lactate to the interstitium. The existence of this lactate pool argues we must reexamine the ‘on demand’ shuttling of lactate between cellular elements, and suggests continuous lactate efflux surplus to immediate neural requirements.

  11. Glycogen Phosphorylase and Glycogen Synthase: Gene Cloning and Expression Analysis Reveal Their Role in Trehalose Metabolism in the Brown Planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae).

    Science.gov (United States)

    Zhang, Lu; Wang, Huijuan; Chen, Jianyi; Shen, Qida; Wang, Shigui; Xu, Hongxing; Tang, Bin

    2017-01-01

    RNA interference has been used to study insects' gene function and regulation. Glycogen synthase (GS) and glycogen phosphorylase (GP) are two key enzymes in carbohydrates' conversion in insects. Glycogen content and GP and GS gene expression in several tissues and developmental stages of the Brown planthopper Nilaparvata lugens Stål (Hemiptera: Delphacidae) were analyzed in the present study, using quantitative reverse-transcription polymerase chain reaction to determine their response to double-stranded trehalases (dsTREs), trehalose-6-phosphate synthases (dsTPSs), and validamycin injection. The highest expression of both genes was detected in the wing bud, followed by leg and head tissues, and different expression patterns were shown across the developmental stages analyzed. Glycogen content significantly decreased 48 and 72 h after dsTPSs injection and 48 h after dsTREs injection. GP expression increased 48 h after dsTREs and dsTPSs injection and significantly decreased 72 h after dsTPSs, dsTRE1-1, and dsTRE1-2 injection. GS expression significantly decreased 48 h after dsTPS2 and dsTRE2 injection and 72 h after dsTRE1-1 and dsTRE1-2 injection. GP and GS expression and glycogen content significantly decreased 48 h after validamycin injection. The GP activity significantly decreased 48 h after validamycin injection, while GS activities of dsTPS1 and dsTRE2 injection groups were significantly higher than that of double-stranded GFP (dsGFP) 48 h after injection, respectively. Thus, glycogen is synthesized, released, and degraded across several insect tissues according to the need to maintain stable trehalose levels. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  12. Effect of pH on Cleavage of Glycogen by Vaginal Enzymes.

    Directory of Open Access Journals (Sweden)

    Greg T Spear

    Full Text Available Glycogen expressed by the lower genital tract epithelium is believed to support Lactobacillus growth in vivo, although most genital isolates of Lactobacillus are not able to use glycogen as an energy source in vitro. We recently reported that α-amylase is present in the genital fluid of women and that it breaks down glycogen into small carbohydrates that support growth of lactobacilli. Since the pH of the lower genital tract can be very low, we determined how low pH affects glycogen processing by α-amylase. α-amylase in saliva degraded glycogen similarly at pH 6 and 7, but activity was reduced by 52% at pH 4. The glycogen degrading activity in nine genital samples from seven women showed a similar profile with an average reduction of more than 50% at pH 4. However, two samples collected from one woman at different times had a strikingly different pH profile with increased glycogen degradation at pH 4, 5 and 6 compared to pH 7. This second pH profile did not correlate with levels of human α-acid glucosidase or human intestinal maltase glucoamylase. High-performance anion-exchange chromatography showed that mostly maltose was produced from glycogen by samples with the second pH profile in contrast to genital α-amylase that yielded maltose, maltotriose and maltotetraose. These studies show that at low pH, α-amylase activity is reduced to low but detectable levels, which we speculate helps maintain Lactobacillus growth at a limited but sustained rate. Additionally, some women have a genital enzyme distinct from α-amylase with higher activity at low pH. Further studies are needed to determine the identity and distribution of this second enzyme, and whether its presence influences the makeup of genital microbiota.

  13. The Csr System Regulates Escherichia coli Fitness by Controlling Glycogen Accumulation and Energy Levels.

    Science.gov (United States)

    Morin, Manon; Ropers, Delphine; Cinquemani, Eugenio; Portais, Jean-Charles; Enjalbert, Brice; Cocaign-Bousquet, Muriel

    2017-10-31

    In the bacterium Escherichia coli , the posttranscriptional regulatory system Csr was postulated to influence the transition from glycolysis to gluconeogenesis. Here, we explored the role of the Csr system in the glucose-acetate transition as a model of the glycolysis-to-gluconeogenesis switch. Mutations in the Csr system influence the reorganization of gene expression after glucose exhaustion and disturb the timing of acetate reconsumption after glucose exhaustion. Analysis of metabolite concentrations during the transition revealed that the Csr system has a major effect on the energy levels of the cells after glucose exhaustion. This influence was demonstrated to result directly from the effect of the Csr system on glycogen accumulation. Mutation in glycogen metabolism was also demonstrated to hinder metabolic adaptation after glucose exhaustion because of insufficient energy. This work explains how the Csr system influences E. coli fitness during the glycolysis-gluconeogenesis switch and demonstrates the role of glycogen in maintenance of the energy charge during metabolic adaptation. IMPORTANCE Glycogen is a polysaccharide and the main storage form of glucose from bacteria such as Escherichia coli to yeasts and mammals. Although its function as a sugar reserve in mammals is well documented, the role of glycogen in bacteria is not as clear. By studying the role of posttranscriptional regulation during metabolic adaptation, for the first time, we demonstrate the role of sugar reserve played by glycogen in E. coli Indeed, glycogen not only makes it possible to maintain sufficient energy during metabolic transitions but is also the key component in the capacity of cells to resume growth. Since the essential posttranscriptional regulatory system Csr is a major regulator of glycogen accumulation, this work also sheds light on the central role of posttranscriptional regulation in metabolic adaptation. Copyright © 2017 Morin et al.

  14. Is Type 2 Diabetes a Glycogen Storage Disease of Pancreatic β Cells?

    Science.gov (United States)

    Ashcroft, Frances M; Rohm, Maria; Clark, Anne; Brereton, Melissa F

    2017-07-05

    Elevated plasma glucose leads to pancreatic β cell dysfunction and death in type 2 diabetes. Glycogen accumulation, due to impaired metabolism, contributes to this "glucotoxicity" via dysregulated biochemical pathways promoting β cell dysfunction. Here, we review emerging data, and re-examine published findings, on the role of glycogen in β cells in normoglycemia and in diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Green Tea Polyphenol Epigallocatechin-3-Gallate Enhance Glycogen Synthesis and Inhibit Lipogenesis in Hepatocytes

    Directory of Open Access Journals (Sweden)

    Jane J. Y. Kim

    2013-01-01

    Full Text Available The beneficial effects of green tea polyphenols (GTP against metabolic syndrome and type 2 diabetes by suppressing appetite and nutrient absorption have been well reported. However the direct effects and mechanisms of GTP on glucose and lipid metabolism remain to be elucidated. Since the liver is an important organ involved in glucose and lipid metabolism, we examined the effects and mechanisms of GTP on glycogen synthesis and lipogenesis in HepG2 cells. Concentrations of GTP containing 68% naturally occurring (−-epigallocatechin-3-gallate (EGCG were incubated in HepG2 cells with high glucose (30 mM under 100 nM of insulin stimulation for 24 h. GTP enhanced glycogen synthesis in a dose-dependent manner. 10 μM of EGCG significantly increased glycogen synthesis by 2fold (P<0.05 compared with insulin alone. Western blotting revealed that phosphorylation of Ser9 glycogen synthase kinase 3β and Ser641 glycogen synthase was significantly increased in GTP-treated HepG2 cells compared with nontreated cells. 10 μM of EGCG also significantly inhibited lipogenesis (P<0.01. We further demonstrated that this mechanism involves enhanced expression of phosphorylated AMP-activated protein kinase α and acetyl-CoA carboxylase in HepG2 cells. Our results showed that GTP is capable of enhancing insulin-mediated glucose and lipid metabolism by regulating enzymes involved in glycogen synthesis and lipogenesis.

  16. Skeletal muscle cellularity and glycogen distribution in the hypermuscular Compact mice

    Directory of Open Access Journals (Sweden)

    T. Kocsis

    2014-07-01

    Full Text Available Normal 0 21 false false false HU X-NONE X-NONE MicrosoftInternetExplorer4 The TGF-beta member myostatin acts as a negative regulator of skeletal muscle mass. The Compact mice were selected for high protein content and hypermuscularity, and carry a naturally occurring 12-bp deletion in the propeptide region of the myostatin precursor. We aimed to investigate the cellular characteristics and the glycogen distribution of the Compact tibialis anterior (TA muscle by quantitative histochemistry and spectrophotometry. We have found that the deficiency in myostatin resulted in significantly increased weight of the investigated hindlimb muscles compared to wild type. Although the average glycogen content of the individual fibers kept unchanged, the total amount of glycogen in the Compact TA muscle increased two-fold, which can be explained by the presence of more fibers in Compact compared to wild type muscle. Moreover, the ratio of the most glycolytic IIB fibers significantly increased in the Compact TA muscle, of which glycogen content was the highest among the fast fibers. In summary, myostatin deficiency caused elevated amount of glycogen in the TA muscle but did not increase the glycogen content of the individual fibers despite the marked glycolytic shift observed in Compact mice.

  17. Pathogenesis of Lafora Disease: Transition of Soluble Glycogen to Insoluble Polyglucosan.

    Science.gov (United States)

    Sullivan, Mitchell A; Nitschke, Silvia; Steup, Martin; Minassian, Berge A; Nitschke, Felix

    2017-08-11

    Lafora disease (LD, OMIM #254780) is a rare, recessively inherited neurodegenerative disease with adolescent onset, resulting in progressive myoclonus epilepsy which is fatal usually within ten years of symptom onset. The disease is caused by loss-of-function mutations in either of the two genes EPM2A (laforin) or EPM2B (malin). It characteristically involves the accumulation of insoluble glycogen-derived particles, named Lafora bodies (LBs), which are considered neurotoxic and causative of the disease. The pathogenesis of LD is therefore centred on the question of how insoluble LBs emerge from soluble glycogen. Recent data clearly show that an abnormal glycogen chain length distribution, but neither hyperphosphorylation nor impairment of general autophagy, strictly correlates with glycogen accumulation and the presence of LBs. This review summarizes results obtained with patients, mouse models, and cell lines and consolidates apparent paradoxes in the LD literature. Based on the growing body of evidence, it proposes that LD is predominantly caused by an impairment in chain-length regulation affecting only a small proportion of the cellular glycogen. A better grasp of LD pathogenesis will further develop our understanding of glycogen metabolism and structure. It will also facilitate the development of clinical interventions that appropriately target the underlying cause of LD.

  18. Excess glycogen does not resolve high ultimate pH of oxidative muscle.

    Science.gov (United States)

    England, Eric M; Matarneh, Sulaiman K; Oliver, Emily M; Apaoblaza, Ariel; Scheffler, Tracy L; Shi, Hao; Gerrard, David E

    2016-04-01

    Skeletal muscle glycogen content can impact the extent of postmortem pH decline. Compared to glycolytic muscles, oxidative muscles contain lower glycogen levels antemortem which may contribute to the higher ultimate pH. In an effort to explore further the participation of glycogen in postmortem metabolism, we postulated that increasing the availability of glycogen would drive additional pH decline in oxidative muscles to equivalent pH values similar to the ultimate pH of glycolytic muscles. Glycolysis and pH declines were compared in porcine longissimus lumborum (glycolytic) and masseter (oxidative) muscles using an in vitro system in the presence of excess glycogen. The ultimate pH of the system containing longissimus lumborum reached a value similar to that observed in intact muscle. The pH decline of the system containing masseter samples stopped prematurely resulting in a higher ultimate pH which was similar to that of intact masseter muscle. To investigate further, we titrated powdered longissimus lumborum and masseter samples in the reaction buffer. As the percentage of glycolytic sample increased, the ultimate pH decreased. These data show that oxidative muscle produces meat with a high ultimate pH regardless of glycogen content and suggest that inherent muscle factors associated with glycolytic muscle control the extent of pH decline in pig muscles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Identification and Functional Characterization of the Glycogen Synthesis Related Gene Glycogenin in Pacific Oysters (Crassostrea gigas).

    Science.gov (United States)

    Li, Busu; Meng, Jie; Li, Li; Liu, Sheng; Wang, Ting; Zhang, Guofan

    2017-09-06

    High glycogen levels in the Pacific oyster (Crassostrea gigas) contribute to its flavor, quality, and hardiness. Glycogenin (CgGN) is the priming glucosyltransferase that initiates glycogen biosynthesis. We characterized the full sequence and function of C. gigas CgGN. Three CgGN isoforms (CgGN-α, β, and γ) containing alternative exon regions were isolated. CgGN expression varied seasonally in the adductor muscle and gonadal area and was the highest in the adductor muscle. Autoglycosylation of CgGN can interact with glycogen synthase (CgGS) to complete glycogen synthesis. Subcellular localization analysis showed that CgGN isoforms and CgGS were located in the cytoplasm. Additionally, a site-directed mutagenesis experiment revealed that the Tyr200Phe and Tyr202Phe mutations could affect CgGN autoglycosylation. This is the first study of glycogenin function in marine bivalves. These findings will improve our understanding of glycogen synthesis and accumulation mechanisms in mollusks. The data are potentially useful for breeding high-glycogen oysters.

  20. Direct vs. indirect pathway of hepatic glycogen synthesis as a function of glucose infusion rate

    International Nuclear Information System (INIS)

    Bagby, G.J.; Lang, C.H.; Johnson, J.L.; Blakesly, H.L.; Spitzer, J.J.

    1986-01-01

    This study was initiated to determine the influence of the rate of exogenous glucose administration on liver glycogen synthesis by the direct (glucose uptake and incorporation into glycogen) vs the indirect pathway (glucose degradation to 3-carbon intermediates, e.g., lactate, prior to incorporation into glycogen). Catheterized rats were fasted 2 days prior to receiving a 3 hr infusion of glucose at rates of 0 to 230 μmol/min/kg containing tracer [6- 3 H]- and [U- 14 C]-glucose. Plasma glucose (r = 0.80), insulin (r = 0.90) and lactate (r = 0.84) were correlated with glucose infusion rate. The rate of liver glycogen deposition (0.46 +/- 0.03 μmol/min/g) did not differ between a glucose infusion rate of 20 and 230 μmol/min/kg. At the lowest and highest glucose infusion rates hepatic glycogenesis accounted for 87 +/- 6 and 9 +/- 1% of the total glucose load, respectively. The percent contribution of the direct pathways to glycogen deposition ([ 3 H] specific activity in hepatic glycogen/[ 3 H] specific activity in plasma glucose) increased from 16 +/- 3 to 83 +/- 5% from lowest to highest glucose infusion rates (prevailing plasma glucose concentrations: 9 +/- 1 and 21 +/- 2 mM, respectively). The results indicate that the relative contribution of the direct and indirect pathways of glucogen synthesis are dependent upon the glucose load or plasma glucose concentration

  1. Nature of complexing of glycogen with iodine in presence of CaCl2

    International Nuclear Information System (INIS)

    Bobrova, L.N.

    1986-01-01

    The absorption and dichroic absorbance of an iodine complex of muscle glycogen were studied as a function of the CaCl 2 concentration. It was found that high CaCl 2 concentrations, at which the staining of glycogen upon interaction with iodine increases sharply, destabilize the α-glucan helix and lead to a disturbance in the formation of a specific chromophore of the iodine-glycogen complex, which is indicated by the loss of dichroism. The stained chromophore appearing upon a simultaneous decrease in the dichroism is evidently produced by a nonhelical mechanism and is therefore nonspecific. This nonspecific chromophore may be the source of errors in spectrophotometric characterization of the structure of glycogens. It was shown using rabbit skeletal muscle and liver glycogens that the Krisman method, in which concentrated solutions of CaCl 2 are used, does not reveal the differences in the structure of the glycogens that are found at low CaCl 2 concentrations. The unfavorable effect of high CaCl 2 concentrations on helix formation must be kept in mind in a determination of the stoichiometry of the interaction of iodine with α-glucan

  2. Predicting glycogen concentration in the foot muscle of abalone using near infrared reflectance spectroscopy (NIRS).

    Science.gov (United States)

    Fluckiger, Miriam; Brown, Malcolm R; Ward, Louise R; Moltschaniwskyj, Natalie A

    2011-06-15

    Near infrared reflectance spectroscopy (NIRS) was used to predict glycogen concentrations in the foot muscle of cultured abalone. NIR spectra of live, shucked and freeze-dried abalones were modelled against chemically measured glycogen data (range: 0.77-40.9% of dry weight (DW)) using partial least squares (PLS) regression. The calibration models were then used to predict glycogen concentrations of test abalone samples and model robustness was assessed from coefficient of determination of the validation (R2(val)) and standard error of prediction (SEP) values. The model for freeze-dried abalone gave the best prediction (R2(val) 0.97, SEP=1.71), making it suitable for quantifying glycogen. Models for live and shucked abalones had R2(val) of 0.86 and 0.90, and SEP of 3.46 and 3.07 respectively, making them suitable for producing estimations of glycogen concentration. As glycogen is a taste-active component associated with palatability in abalone, this study demonstrated the potential of NIRS as a rapid method to monitor the factors associated with abalone quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Isoform-selective regulation of glycogen phosphorylase by energy deprivation and phosphorylation in astrocytes.

    Science.gov (United States)

    Müller, Margit S; Pedersen, Sofie E; Walls, Anne B; Waagepetersen, Helle S; Bak, Lasse K

    2015-01-01

    Glycogen phosphorylase (GP) is activated to degrade glycogen in response to different stimuli, to support both the astrocyte's own metabolic demand and the metabolic needs of neurons. The regulatory mechanism allowing such a glycogenolytic response to distinct triggers remains incompletely understood. In the present study, we used siRNA-mediated differential knockdown of the two isoforms of GP expressed in astrocytes, muscle isoform (GPMM), and brain isoform (GPBB), to analyze isoform-specific regulatory characteristics in a cellular setting. Subsequently, we tested the response of each isoform to phosphorylation, triggered by incubation with norepinephrine (NE), and to AMP, increased by glucose deprivation in cells in which expression of one GP isoform had been silenced. Successful knockdown was demonstrated on the protein level by Western blot, and on a functional level by determination of glycogen content showing an increase in glycogen levels following knockdown of either GPMM or GPBB. NE triggered glycogenolysis within 15 min in control cells and after GPBB knockdown. However, astrocytes in which expression of GPMM had been silenced showed a delay in response to NE, with glycogen levels significantly reduced only after 60 min. In contrast, allosteric activation of GP by AMP, induced by glucose deprivation, seemed to mainly affect GPBB, as only knockdown of GPBB, but not of GPMM, delayed the glycogenolytic response to glucose deprivation. Our results indicate that the two GP isoforms expressed in astrocytes respond to different physiological triggers, therefore conferring distinct metabolic functions of brain glycogen. © 2014 Wiley Periodicals, Inc.

  4. Glycogen storage disease type I: clinical and laboratory profile

    Directory of Open Access Journals (Sweden)

    Berenice L. Santos

    2014-11-01

    Full Text Available Objectives: To characterize the clinical, laboratory, and anthropometric profile of a sample of Brazilian patients with glycogen storage disease type I managed at an outpatient referral clinic for inborn errors of metabolism. Methods: This was a cross-sectional outpatient study based on a convenience sampling strategy. Data on diagnosis, management, anthropometric parameters, and follow-up were assessed. Results: Twenty-one patients were included (median age 10 years, range 1–25 years, all using uncooked cornstarch therapy. Median age at diagnosis was 7 months (range, 1–132 months, and 19 patients underwent liver biopsy for diagnostic confirmation. Overweight, short stature, hepatomegaly, and liver nodules were present in 16 of 21, four of 21, nine of 14, and three of 14 patients, respectively. A correlation was found between height-for-age and BMI-for-age Z-scores (r = 0.561; p = 0.008. Conclusions: Diagnosis of glycogen storage disease type I is delayed in Brazil. Most patients undergo liver biopsy for diagnostic confirmation, even though the combination of a characteristic clinical presentation and molecular methods can provide a definitive diagnosis in a less invasive manner. Obesity is a side effect of cornstarch therapy, and appears to be associated with growth in these patients. Resumo: Objetivos: Caracterizar o perfil clínico, laboratorial e antropométrico de uma amostra de pacientes brasileiros com doença de depósito de glicogênio tipo I tratados em um ambulatório de referência para erros inatos do metabolismo. Métodos: Este foi um estudo ambulatorial transversal com base em uma estratégia de amostragem de conveniência. Foram avaliados os dados com relação ao diagnóstico, tratamento, parâmetros antropométricos e acompanhamento. Resultados: Foram incluídos 21 pacientes (idade média de 10 anos, faixa 1-25 anos de idade, e todos se encontravam em terapia de amido de milho cru. A idade média na época do diagn

  5. A Dual Function Energy Store

    Directory of Open Access Journals (Sweden)

    Ron Tolmie

    2014-11-01

    Full Text Available Heat can be collected from local energy sources and concentrated into a relatively small volume, and at a useful working temperature, by using a heat pump as the concentrator. That heat can be stored and utilized at a later date for applications like space heating. The process is doing two things at the same time: storing heat and shifting the power demand. The concentration step can be done at night when there is normally a surplus of power and its timing can be directly controlled by the power grid operator to ensure that the power consumption occurs only when adequate power is available. The sources of heat can be the summer air, the heat extracted from buildings by their cooling systems, natural heat from the ground or solar heat, all of which are free, abundant and readily accessible. Such systems can meet the thermal needs of buildings while at the same time stabilizing the grid power demand, thus reducing the need for using fossil-fuelled peaking power generators. The heat pump maintains the temperature of the periphery at the ambient ground temperature so very little energy is lost during storage.

  6. Method of storing radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, M; Kamiya, K; Sugimoto, Y

    1976-01-09

    A method is claimed to decrease the number of storage containers filled with radioactive wastes. A wire-netting containers having a capacity of 67 liters is filled with 60 kg of pellet-like radioactive solid material. The wire-netting container is held in the middle of a drum can, and asphalt is poured between the drum can and the wire-netting container and stored until radioactivity is attenuated. After storage, the stored body is heated to melt the asphalt and the wire-netting container is removed. Thereafter, the pellet-like radioactive solid material is taken out of the wire-netting container and combined with the other pellet-like radioactive solid material similarly taken out of the storage container, and the resultant material is filled into a wire-netting container having a capacity of 167 liters every 150 kg, and inserted again into the same drum can, into which recovered asphalt is poured for final storage.

  7. [Occupational risks in grocery stores].

    Science.gov (United States)

    Graziosi, Francesca; Bonfiglioli, Roberta; Violante, Francesco S

    2014-01-01

    This work provides an overview of the spectrum of possible occupational risk factors in the retail grocery store/supermarket workplace. Literature on this theme, obtained consulting PubMed database and Google Scholar, was checked. We also exjlore results from the National bInstitute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). RESULTs: Contacts with objects, use of dangerous equipment (cutter, food slicer) and falls to the same level (slips, trips and falls) are the mainly described workplace hazards. Exposure to chemical (flour dust, components of detergents or disinfectants, volatile organic compounds and contact with nickel) and physical agents (cold exposure, nonionizing radiation and whole bpdy vibration) are reported by many authors. Relations between biomechanical and ergonomic risk factors and musculoskeletal disorders represent the main subjects of study. Few studies are found about biological agents (particularly among butchers). Data regarding psychosocial risks factors in this setting are still limited. Musculoskeletal disorders continue to be the most recurrent health problem between the grocery store workers (particularly low back pain and carpal tunnel syndrome among cashiers). Many technical documents and international Srecommendations are present to prevent these kinds of disorders. Psychosocial risk factors and risk of workplace violence should deserve further investigation.

  8. 16-channel analog store and multiplexer unit

    Energy Technology Data Exchange (ETDEWEB)

    Brossard, M; Kulka, Z [Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire

    1979-03-15

    A 16-channel analog store and multiplexer unit is described. The unit enables storing and selection of analog information which is then digitally encoded by single ADC. This solution becomes economically attractive particularly in multidetector pulse height analysis systems.

  9. Store Separations From a Supersonic Cone

    National Research Council Canada - National Science Library

    Simko, Richard J

    2006-01-01

    ... analyses of supersonic store separations. Also included in this research is a study of supersonic base pressure profiles, near-wake velocity profiles, wind tunnel shock interactions and force/moment studies on a conical store and parent vehicle...

  10. Short and long-term effects of internal irradiation on the murine hepatic glycogen and its metabolizing enzymes

    International Nuclear Information System (INIS)

    Gupta, N.K.

    1990-01-01

    Glycogen content and the activities of phosphorylase, phosphorhexose isomerase, glucose 6-phosphatase, glycogen synthesis' phosphorylase and succinate dehydrogenase have been biochemically determined in the liver of Swiss albino mice after radiocalcium internal irradiation up to 225 days posttreatment. Increase in the glycogen content and glycogen synthesis phosphorylase with a concomitant decrease in the activities of phosphorylase, glucose 6-phosphatase, phosphohexose isomerase and succinate dehydrogenase reveals inhibited glycolysis in the presence of normal glyogenesis and inhibited Kreb's cycle in the liver during early intervals. Decrease in the glycogen content at later stages along with decrease in the activities of all these enzymes is probably because of an inhibited glycogen biosynthesis and its catabolism through HMP shunt. (orig.)

  11. In-Store Media and Channel Management

    OpenAIRE

    Anthony Dukes; Yunchuan Liu

    2007-01-01

    In this paper, we study the interesting and complicated effects of retailer in-store media on distribution channel relationships. With the help of advanced technology, retailers can open in-store media in their stores and allow manufacturers to advertise through the instore media. We show that opening in-store media is a strategic decision for a retailer, and a retailer may strategically subsidize manufacturers on their advertising through instore media to better coordinate the channel. Even ...

  12. Consumer behaviour in Apple's App Store

    OpenAIRE

    Ayalew, Romel

    2011-01-01

    Mobile applications stores such as Apple’s App Store and Google’s Android Market revolutionized the distribution of applications for mobile devices. However, with thousands of application submissions, limited testing resources and the lack of an effective filtering mechanism, application stores suffer from information overload and a risk of releasing poor quality applications that could create confusion to consumers and may seriously affect the App store markets. Thus concern has been raised ...

  13. Corner stores: the perspective of urban youth.

    Science.gov (United States)

    Sherman, Sandra; Grode, Gabrielle; McCoy, Tara; Vander Veur, Stephanie S; Wojtanowski, Alexis; Sandoval, Brianna Almaguer; Foster, Gary D

    2015-02-01

    We examined the perspectives of low-income, urban youth about the corner store experience to inform the development of corner store interventions. Focus groups were conducted to understand youth perceptions regarding their early shopping experiences, the process of store selection, reasons for shopping in a corner store, parental guidance about corner stores, and what their ideal, or "dream corner store" would look like. Thematic analysis was employed to identify themes using ATLAS.ti (version 6.1, 2010, ATLAS.ti GmbH) and Excel (version 2010, Microsoft Corp). Focus groups were conducted in nine kindergarten-through-grade 8 (K-8) public schools in low-income neighborhoods with 40 fourth- to sixth-graders with a mean age of 10.9±0.8 years. Youth report going to corner stores with family members at an early age. By second and third grades, a growing number of youth reported shopping unaccompanied by an older sibling or adult. Youth reported that the products sold in stores were the key reason they choose a specific store. A small number of youth said their parents offered guidance on their corner store purchases. When youth were asked what their dream corner store would look like, they mentioned wanting a combination of healthy and less-healthy foods. These data suggest that, among low-income, urban youth, corner store shopping starts at a very young age and that product, price, and location are key factors that affect corner store selection. The data also suggest that few parents offer guidance about corner store purchases, and youth are receptive to having healthier items in corner stores. Corner store intervention efforts should target young children and their parents/caregivers and aim to increase the availability of affordable, healthier products. Copyright © 2015 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  14. Retail brand architecture and consumer store loyalty

    DEFF Research Database (Denmark)

    Brunsø, Karen; Grunert, Klaus G.

    is to investigate the relationship between consumers perceived retail brand architecture, their store satisfaction and loyalty. Furthermore we use perceived store image as a mediating factor in our framework. In total 772 Danish households participated in a telephone interview and returned questionnaires by mail....... The major contribution of this research is to conceptualise and empirically investigate the role of brand architecture for perceived store image, store satisfaction and loyalty....

  15. Identification of differentially expressed genes in chickens differing in muscle glycogen content and meat quality

    Directory of Open Access Journals (Sweden)

    Marthey Sylvain

    2011-02-01

    Full Text Available Abstract Background The processing ability of poultry meat is highly related to its ultimate pH, the latter being mainly determined by the amount of glycogen in the muscle at death. The genetic determinism of glycogen and related meat quality traits has been established in the chicken but the molecular mechanisms involved in variations in these traits remain to be fully described. In this study, Chicken Genome Arrays (20 K were used to compare muscle gene expression profiles of chickens from Fat (F and Lean (L lines that exhibited high and low muscle glycogen content, respectively, and of individuals exhibiting extremely high (G+ or low (G- muscle glycogen content originating from the F2 cross between the Fat and Lean lines. Real-time RT-PCR was subsequently performed to validate the differential expression of genes either selected from the microarray analysis or whose function in regulating glycogen metabolism was well known. Results Among the genes found to be expressed in chicken P. major muscle, 197 and 254 transcripts appeared to be differentially expressed on microarrays for the F vs. L and the G+ vs. G- comparisons, respectively. Some involved particularly in lipid and carbohydrate metabolism were selected for further validation studies by real-time RT-PCR. We confirmed that, as in mammals, the down-regulation of CEBPB and RGS2 coincides with a decrease in peripheral adiposity in the chicken, but these genes are also suggested to affect muscle glycogen turnover through their role in the cAMP-dependent signalling pathway. Several other genes were suggested to have roles in the regulation of glycogen storage in chicken muscle. PDK4 may act as a glycogen sensor in muscle, UGDH may compete for glycogen synthesis by using UDP-glucose for glucoronidation, and PRKAB1, PRKAG2, and PHKD may impact on glycogen turnover in muscle, through AMP-activated signalling pathways. Conclusions This study is the first stage in the understanding of molecular

  16. The Q(s,S) control policy for the joint replenishment problem extended to the case of correlation among item-demands

    DEFF Research Database (Denmark)

    Larsen, Christian

    2009-01-01

    We develop an algorithm to compute an optimal Q(s,S) policy for the joint replenishment problem when demands follow a compound correlated Poisson process. It is a non-trivial generalization of the work by Nielsen and Larsen [2005. An analytical study of the Q(s,S) policy applied to the joint...... replenishment problem. European Journal of Operational Research 163, 721-732]. We make some numerical analyses on two-item problems where we compare the optimal Q(s,S) policy to the optimal uncoordinated (s,S) policies. The results indicate that the more negative the correlation the less advantageous...

  17. Apparatus for storing protective suits

    International Nuclear Information System (INIS)

    Englemann, H.J.; Koller, J.; Schrader, H.R.; Schade, G.; Pedrerol, J.

    1975-01-01

    Arrangements are described for storing one or more protective suits when contaminated on the outside. In order to permit a person wearing a contaminated suit to leave a contaminated area safely, and without contaminating the environment, it has hitherto been the practice for the suit to be passed through a 'lock' and cleansed under decontaminating showers whilst still being worn. This procedure is time wasting and not always completely effective, and it may be necessary to provide a second suit for use whilst the first suit is being decontaminated. Repeated decontamination may also result in undue wear and tear. The arrangements described provide a 'lock' chamber in which a contaminated suit may be stowed away without its interior becoming contaminated, thus allowing repeated use by persons donning and shedding it. (U.K.)

  18. Glycogen synthase kinase-3 regulation of urinary concentrating ability.

    Science.gov (United States)

    Rao, Reena

    2012-09-01

    Glycogen synthase kinase-3 (GSK3) is an enzyme that is gaining prominence as a critical signaling molecule in the epithelial cells of renal tubules. This review will focus on recent findings exploring the role of GSK3 in renal collecting ducts, especially its role in urine concentration involving vasopressin signaling. Recent studies using inhibition or tissue-specific gene deletion of GSK3 revealed the mechanism by which GSK3 regulates aquaporin 2 water channels via adenylate cyclase or the prostaglandin-E2 pathway. In other studies, postnatal treatment with lithium, an inhibitor of GSK3, increased cell proliferation and led to microcyst formation in rat kidneys. These studies suggest that loss of GSK3 activity could interfere with renal water transport at two levels. In the short term, it could disrupt vasopressin signaling in collecting duct cells and in the long term it could alter the structure of the collecting ducts, making them less responsive to the hydro-osmotic effects of vasopressin. Ongoing studies reveal the crucial role played by GSK3 in the regulation of vasopressin action in the renal collecting ducts and suggest a possible use of GSK3 inhibitors in disease conditions associated with disrupted vasopressin signaling.

  19. Glycogen synthase kinase-3 regulates inflammatory tolerance in astrocytes

    Science.gov (United States)

    Beurel, Eléonore; Jope, Richard S.

    2010-01-01

    Inflammatory tolerance is the down-regulation of inflammation upon repeated stimuli, which is well-established to occur in peripheral immune cells. However, less is known about inflammatory tolerance in the brain although it may provide an important protective mechanism from detrimental consequences of prolonged inflammation, which appears to occur in many psychiatric and neurodegenerative conditions. Array analysis of 308 inflammatory molecules produced by mouse primary astrocytes after two sequential stimulations with lipopolysaccharide (LPS) distinguished three classes, tolerant, sensitized and unaltered groups. For many of these inflammatory molecules, inhibition of glycogen synthase kinase-3 (GSK3) increased tolerance and reduced sensitization. Focusing on LPS-tolerance in interleukin-6 (IL-6) production, we found that microglia exhibited a strong tolerance response that matched that of macrophages, whereas astrocytes exhibited only partial tolerance. The astrocyte semi-tolerance was found to be regulated by GSK3. GSK3 inhibitors or knocking down GSK3 levels promoted LPS-tolerance and astrocytes expressing constitutively active GSK3 did not develop LPS-tolerance. These findings identify the critical role of GSK3 in counteracting IL-6 inflammatory tolerance in cells of the CNS, supporting the therapeutic potential of GSK3 inhibitors to reduce neuroinflammation by promoting tolerance. PMID:20553816

  20. Alcoholic fermentation of stored sweet potatoes

    Energy Technology Data Exchange (ETDEWEB)

    Yutaka, Y; One, H

    1958-01-01

    Sweet potatoes were ground and stored in a ground hold. The stored sweet potatoes gave about 90% fermentation efficiency by the koji process. A lower fermentation efficiency by the amylo process was improved by adding 20 to 30 mg/100 ml of organic N. Inorganic N has no effect in improving the fermentation efficiency of the stored sweet potatoes by the amylo process.

  1. Mechanism of store-operated calcium entry

    Indian Academy of Sciences (India)

    Activation of receptors coupled to the phospholipase C/IP3 signalling pathway results in a rapid release of calcium from its intracellular stores, eventually leading to depletion of these stores. Calcium store depletion triggers an influx of extracellular calcium across the plasma membrane, a mechanism known as the ...

  2. Neutropenia, neutrophil dysfunction, and inflammatory bowel disease in glycogen storage disease type Ib : Results of the European Study on Glycogen Storage Disease Type I

    NARCIS (Netherlands)

    Visser, G; Rake, JP; Fernandes, J; Labrune, P; Leonard, JV; Moses, S; Ullrich, K; Smit, GPA

    Objective: To investigate the incidence, the severity, and the course of neutropenia, neutrophil dysfunction, and inflammatory bowel disease (IBD) in glycogen storage disease (GSD) type Ib. Method: As part of a collaborative European Study on GSD type I, a retrospective registry was established in

  3. Granulocyte colony-stimulating factor in glycogen storage disease type 1b. Results of the European Study on Glycogen Storage Disease Type 1

    NARCIS (Netherlands)

    Visser, G.; Rake, J.P.; Labrune, P.; Leonard, J.V.; Moses, S.; Ullrich, K.; Wendel, U.; Groenier, K.H.; Smit, G.P.

    2002-01-01

    Patients with glycogen storage disease type 1b (GSD-1b) have neutropenia and neutrophil dysfunction that predispose to frequent infections and inflammatory bowel disease (IBD), for which granulocyte colony-stimulating factor (GCSF) is given. To investigate the use and the value of GCSF treatment in

  4. GLAM: Glycogen-derived Lactate Absorption Map for visual analysis of dense and sparse surface reconstructions of rodent brain structures on desktop systems and virtual environments

    KAUST Repository

    Agus, Marco; Boges, Daniya; Gagnon, Nicolas; Magistretti, Pierre J.; Hadwiger, Markus; Cali, Corrado

    2018-01-01

    Human brain accounts for about one hundred billion neurons, but they cannot work properly without ultrastructural and metabolic support. For this reason, mammalian brains host another type of cells called “glial cells”, whose role is to maintain proper conditions for efficient neuronal function. One type of glial cell, astrocytes, are involved in particular in the metabolic support of neurons, by feeding them with lactate, one byproduct of glucose metabolism that they can take up from blood vessels, and store it under another form, glycogen granules. These energy-storage molecules, whose morphology resembles to spheres with a diameter ranging 10–80 nanometers roughly, can be easily recognized using electron microscopy, the only technique whose resolution is high enough to resolve them. Understanding and quantifying their distribution is of particular relevance for neuroscientists, in order to understand where and when neurons use energy under this form. To answer this question, we developed a visualization technique, dubbed GLAM (Glycogen-derived Lactate Absorption Map), and customized for the analysis of the interaction of astrocytic glycogen on surrounding neurites in order to formulate hypotheses on the energy absorption mechanisms. The method integrates high-resolution surface reconstruction of neurites, astrocytes, and the energy sources in form of glycogen granules from different automated serial electron microscopy methods, like focused ion beam scanning electron microscopy (FIB-SEM) or serial block face electron microscopy (SBEM), together with an absorption map computed as a radiance transfer mechanism. The resulting visual representation provides an immediate and comprehensible illustration of the areas in which the probability of lactate shuttling is higher. The computed dataset can be then explored and quantified in a 3D space, either using 3D modeling software or virtual reality environments. Domain scientists have evaluated the technique by

  5. GLAM: Glycogen-derived Lactate Absorption Map for visual analysis of dense and sparse surface reconstructions of rodent brain structures on desktop systems and virtual environments

    KAUST Repository

    Agus, Marco

    2018-05-21

    Human brain accounts for about one hundred billion neurons, but they cannot work properly without ultrastructural and metabolic support. For this reason, mammalian brains host another type of cells called “glial cells”, whose role is to maintain proper conditions for efficient neuronal function. One type of glial cell, astrocytes, are involved in particular in the metabolic support of neurons, by feeding them with lactate, one byproduct of glucose metabolism that they can take up from blood vessels, and store it under another form, glycogen granules. These energy-storage molecules, whose morphology resembles to spheres with a diameter ranging 10–80 nanometers roughly, can be easily recognized using electron microscopy, the only technique whose resolution is high enough to resolve them. Understanding and quantifying their distribution is of particular relevance for neuroscientists, in order to understand where and when neurons use energy under this form. To answer this question, we developed a visualization technique, dubbed GLAM (Glycogen-derived Lactate Absorption Map), and customized for the analysis of the interaction of astrocytic glycogen on surrounding neurites in order to formulate hypotheses on the energy absorption mechanisms. The method integrates high-resolution surface reconstruction of neurites, astrocytes, and the energy sources in form of glycogen granules from different automated serial electron microscopy methods, like focused ion beam scanning electron microscopy (FIB-SEM) or serial block face electron microscopy (SBEM), together with an absorption map computed as a radiance transfer mechanism. The resulting visual representation provides an immediate and comprehensible illustration of the areas in which the probability of lactate shuttling is higher. The computed dataset can be then explored and quantified in a 3D space, either using 3D modeling software or virtual reality environments. Domain scientists have evaluated the technique by

  6. [Experimental study on the treatment of serious soft tissue injuries with strengthening the spleen and replenishing qi].

    Science.gov (United States)

    Chen, Xun-wen; Zhu, Yong-zhan; Chen, Zhi-wei; Wu, Zheng-jie; He, Li-lei

    2008-09-01

    To study the effects of Chinese drugs based on strengthening the spleen and replenishing qi treatment rule on neoformative capillaries and fibroblast during the soft tissue repair after serious trauma in rats, so as to explore the biological basis of the TCM theory "the spleen dominate extremities and muscles" applied to the treatment of soft tissue injuries. The model rats were established by bleeding from femoral artery and lancing method, and the rats were randomly divided into the control group, strengthening the spleen group and activating blood and resolving stasis group. The samples were got from the tissue of the wounded area at the 5th, 10th and 15th days after oral administration of the traditional Chinese medicine. After fixation and section, the tissues were stained by CD31 and PCNA staining. The amount of the capillaries and fibroblasts in the tissue of the wounded area were observed through multi-purpose microscope (ZEISS Axioskop2). Quantitative analysis was carried out on Image-ProPlus image analyzer. The amount of the capillaries and fibroblasts in the wounded tissue in the strengthening the spleen group were larger than that in the control group at the 5th, 10th and 15th day. And the proliferation speed of capillaries and fibroblasts was faster than those in the control group or the activating blood and resolving stasis group. The Chinese drugs according to strengthening the spleen and replenishing qi treatment rule were effective to promote growth of the granulation tissue and facilitate healing of the wounded area. And it has better effect than the treatment of promoting blood circulation and removing stasis.

  7. Human α-amylase present in lower-genital-tract mucosal fluid processes glycogen to support vaginal colonization by Lactobacillus.

    Science.gov (United States)

    Spear, Gregory T; French, Audrey L; Gilbert, Douglas; Zariffard, M Reza; Mirmonsef, Paria; Sullivan, Thomas H; Spear, William W; Landay, Alan; Micci, Sandra; Lee, Byung-Hoo; Hamaker, Bruce R

    2014-10-01

    Lactobacillus colonization of the lower female genital tract provides protection from the acquisition of sexually transmitted diseases, including human immunodeficiency virus, and from adverse pregnancy outcomes. While glycogen in vaginal epithelium is thought to support Lactobacillus colonization in vivo, many Lactobacillus isolates cannot utilize glycogen in vitro. This study investigated how glycogen could be utilized by vaginal lactobacilli in the genital tract. Several Lactobacillus isolates were confirmed to not grow in glycogen, but did grow in glycogen-breakdown products, including maltose, maltotriose, maltopentaose, maltodextrins, and glycogen treated with salivary α-amylase. A temperature-dependent glycogen-degrading activity was detected in genital fluids that correlated with levels of α-amylase. Treatment of glycogen with genital fluids resulted in production of maltose, maltotriose, and maltotetraose, the major products of α-amylase digestion. These studies show that human α-amylase is present in the female lower genital tract and elucidates how epithelial glycogen can support Lactobacillus colonization in the genital tract. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Liver glycogen in type 2 diabetic mice is randomly branched as enlarged aggregates with blunted glucose release.

    Science.gov (United States)

    Besford, Quinn Alexander; Zeng, Xiao-Yi; Ye, Ji-Ming; Gray-Weale, Angus

    2016-02-01

    Glycogen is a vital highly branched polymer of glucose that is essential for blood glucose homeostasis. In this article, the structure of liver glycogen from mice is investigated with respect to size distributions, degradation kinetics, and branching structure, complemented by a comparison of normal and diabetic liver glycogen. This is done to screen for differences that may result from disease. Glycogen α-particle (diameter ∼ 150 nm) and β-particle (diameter ∼ 25 nm) size distributions are reported, along with in vitro γ-amylase degradation experiments, and a small angle X-ray scattering analysis of mouse β-particles. Type 2 diabetic liver glycogen upon extraction was found to be present as large loosely bound, aggregates, not present in normal livers. Liver glycogen was found to aggregate in vitro over a period of 20 h, and particle size is shown to be related to rate of glucose release, allowing a structure-function relationship to be inferred for the tissue specific distribution of particle types. Application of branching theories to small angle X-ray scattering data for mouse β-particles revealed these particles to be randomly branched polymers, not fractal polymers. Together, this article shows that type 2 diabetic liver glycogen is present as large aggregates in mice, which may contribute to the inflexibility of interconversion between glucose and glycogen in type 2 diabetes, and further that glycogen particles are randomly branched with a size that is related to the rate of glucose release.

  9. The glycogen metabolism via Akt signaling is important for the secretion of enamel matrix in tooth development.

    Science.gov (United States)

    Ida-Yonemochi, Hiroko; Otsu, Keishi; Ohshima, Hayato; Harada, Hidemitsu

    2016-02-01

    Cells alter their energy metabolism depending on the stage of differentiation or various environments. In the ameloblast differentiation of continuous growing mouse incisors, we found temporary glycogen storage in preameloblasts before the start of enamel matrix secretion and investigated the relationship between enamel matrix secretion and glycogen metabolism. Immunohistochemistry showed that in the transitional stage from preameloblasts to secretory ameloblasts, the glycogen synthase changed from the inactive form to the active form, the expression of glycogen phosphorylase increased, and further, the levels of IGF-1, IGF-1 receptor and activated Akt increased. These results suggested that the activation of Akt signaling via IGF is linked to the onset of both glycogen metabolism and enamel matrix deposition. In the experiments using organ culture and ameloblast cell line, the activation of Akt signaling by IGF-1 stimulated glycogen metabolism through the up-regulation of Glut-1,-4 and Gsk-3β and the dephosphorylation of glycogen synthase. Subsequently, they resulted in increased enamel matrix secretion. In contrast, some inhibitors of Akt signals and glycogen synthesis/degradation down-regulated enamel matrix secretion. Taking these findings together, glycogen metabolism via Akt signaling is an essential system for the secretion of enamel matrix in ameloblast differentiation. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Characterization of a canine model of glycogen storage disease type IIIa

    Directory of Open Access Journals (Sweden)

    Haiqing Yi

    2012-11-01

    Glycogen storage disease type IIIa (GSD IIIa is an autosomal recessive disease caused by deficiency of glycogen debranching enzyme (GDE in liver and muscle. The disorder is clinically heterogeneous and progressive, and there is no effective treatment. Previously, a naturally occurring dog model for this condition was identified in curly-coated retrievers (CCR. The affected dogs carry a frame-shift mutation in the GDE gene and have no detectable GDE activity in liver and muscle. We characterized in detail the disease expression and progression in eight dogs from age 2 to 16 months. Monthly blood biochemistry revealed elevated and gradually increasing serum alanine transaminase (ALT, aspartate transaminase (AST and alkaline phosphatase (ALP activities; serum creatine phosphokinase (CPK activity exceeded normal range after 12 months. Analysis of tissue biopsy specimens at 4, 12 and 16 months revealed abnormally high glycogen contents in liver and muscle of all dogs. Fasting liver glycogen content increased from 4 months to 12 months, but dropped at 16 months possibly caused by extended fibrosis; muscle glycogen content continually increased with age. Light microscopy revealed significant glycogen accumulation in hepatocytes at all ages. Liver histology showed progressive, age-related fibrosis. In muscle, scattered cytoplasmic glycogen deposits were present in most cells at 4 months, but large, lake-like accumulation developed by 12 and 16 months. Disruption of the contractile apparatus and fraying of myofibrils was observed in muscle at 12 and 16 months by electron microscopy. In conclusion, the CCR dogs are an accurate model of GSD IIIa that will improve our understanding of the disease progression and allow opportunities to investigate treatment interventions.

  11. Quantitative comparison of pathways of hepatic glycogen repletion in fed and fasted humans

    International Nuclear Information System (INIS)

    Shulman, G.I.; Cline, G.; Schumann, W.C.; Chandramouli, V.; Kumaran, K.; Landau, B.R.

    1990-01-01

    The effect of fasting vs. refeeding on hepatic glycogen repletion by the direct pathway, i.e., glucose----glucose 6-phosphate (G-6-P)----glycogen, was determined. Acetaminophen was administered during an infusion of glucose labeled with [1-13C]- and [6-14C]glucose into four healthy volunteers after an overnight fast and into the same subjects 4 h after breakfast. 13C enrichments in C-1 and C-6 of glucose formed from urinary acetaminophen glucuronide compared with enrichments in C-1 and C-6 of plasma glucose provided an estimate of glycogen formation by the direct pathway. The specific activity of glucose from the glucuronide compared with the specific activity of the plasma glucose, along with the percentages of 14C in C-1 and C-6 of the glucose from the glucuronide, also provided an estimate of the amount of glycogen formed by the direct pathway. The estimates were similar. Those from [6-14C]glucose would have been higher than from [1-13C]glucose if the pentose cycle contribution to overall glucose utilization had been significant. After an overnight fast, during the last hour of infusion, 49 +/- 3% of the glycogen formed was formed via the direct pathway. After breakfast, at similar plasma glucose and insulin concentrations, the percentage increased to 69 +/- 7% (P less than 0.02). Thus the contributions of the pathways to hepatic glycogen formation depend on the dietary state of the individual. For a dietary regimen in which individuals consume multiple meals per day containing at least a moderate amount of carbohydrates most glycogen synthesis occurs by the direct pathway

  12. Manipulation of Muscle Creatine and Glycogen Changes Dual X-ray Absorptiometry Estimates of Body Composition.

    Science.gov (United States)

    Bone, Julia L; Ross, Megan L; Tomcik, Kristyen A; Jeacocke, Nikki A; Hopkins, Will G; Burke, Louise M

    2017-05-01

    Standardizing a dual x-ray absorptiometry (DXA) protocol is thought to provide a reliable measurement of body composition. We investigated the effects of manipulating muscle glycogen and creatine content independently and additively on DXA estimates of lean mass. Eighteen well-trained male cyclists undertook a parallel group application of creatine loading (n = 9) (20 g·d for 5 d loading; 3 g·d maintenance) or placebo (n = 9) with crossover application of glycogen loading (12 v 6 g·kg BM per day for 48 h) as part of a larger study involving a glycogen-depleting exercise protocol. Body composition, total body water, muscle glycogen and creatine content were assessed via DXA, bioelectrical impedance spectroscopy and standard biopsy techniques. Changes in the mean were assessed using the following effect-size scale: >0.2 small, >0.6, moderate, >1.2 large and compared with the threshold for the smallest worthwhile effect of the treatment. Glycogen loading, both with and without creatine loading, resulted in substantial increases in estimates of lean body mass (mean ± SD; 3.0% ± 0.7% and 2.0% ± 0.9%) and leg lean mass (3.1% ± 1.8% and 2.6% ± 1.0%) respectively. A substantial decrease in leg lean mass was observed after the glycogen depleting condition (-1.4% ± 1.6%). Total body water showed substantial increases after glycogen loading (2.3% ± 2.3%), creatine loading (1.4% ± 1.9%) and the combined treatment (2.3% ± 1.1%). Changes in muscle metabolites and water content alter DXA estimates of lean mass during periods in which minimal change in muscle protein mass is likely. This information needs to be considered in interpreting the results of DXA-derived estimates of body composition in athletes.

  13. Fed-batch cultivation of baker's yeast followed by nitrogen or carbon starvation: effects on fermentative capacity and content of trehalose and glycogen

    DEFF Research Database (Denmark)

    Jørgensen, Henning; Olsson, Lisbeth; Rønnow, B.

    2002-01-01

    , trehalose and glycogen. Nitrogen starvation triggered the accumulation of trehalose and glycogen. After 8 h of starvation, the content of trehalose and glycogen was increased 4-fold and 2-fold, respectively. Carbon starvation resulted in a partial conversion of glycogen into trehalose. The trehalose content...... increased from 45 to 64 mg (g dry-weight)(-1), whereas the glycogen content in the same period was reduced from 55 to 5 mg (g dry-weight)(-1). Glycogen was consumed faster than trehalose during storage of the starved yeast for 1 month. Nitrogen starvation resulted in a decrease in the protein content...

  14. Reduced plasma adiponectin concentrations may contribute to impaired insulin activation of glycogen synthase in skeletal muscle of patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Højlund, K.; Frystyk, J.; Levin, K.

    2006-01-01

    AIMS/HYPOTHESIS: Circulating levels of adiponectin are negatively associated with multiple indices of insulin resistance, and the concentration is reduced in humans with insulin resistance and type 2 diabetes. However, the mechanisms by which adiponectin improves insulin sensitivity remain unclear...... (ten lean, 21 obese and 20 with type 2 diabetes). RESULTS: Plasma adiponectin was significantly reduced in type 2 diabetic compared with obese and lean subjects. In lean and obese subjects, insulin significantly reduced plasma adiponectin, but this response was blunted in patients with type 2 diabetes...... by improving the capacity to switch from lipid to glucose oxidation and to store glucose as glycogen in response to insulin, and that low adiponectin may contribute to impaired insulin activation of GS in skeletal muscle of patients with type 2 diabetes....

  15. Slow, stopped and stored light

    International Nuclear Information System (INIS)

    Welch, G.; Scully, M.

    2005-01-01

    Light that can been slowed to walking pace could have applications in telecommunications, optical storage and quantum computing. Whether we use it to estimate how far away a thunderstorm is, or simply take it for granted that we can have a conversation with someone on the other side of the world, we all know that light travels extremely fast. Indeed, special relativity teaches us that nothing in the universe can ever move faster than the speed of light in a vacuum: 299 792 458 ms sup - sup 1. However, there is no such limitation on how slowly light can travel. For the last few years, researchers have been routinely slowing light to just a few metres per second, and have recently even stopped it dead in its tracks so that it can be stored for future use. Slow-light has considerable popular appeal, deriving perhaps from the importance of the speed of light in relativity and cosmology. If everyday objects such as cars or people can travel faster than 'slow' light, for example, then it might appear that relativistic effects could be observed at very low speeds. Although this is not the case, slow light nonetheless promises to play an important role in optical technology because it allows light to be delayed for any period of time desired. This could lead to all-optical routers that would increase the bandwidth of the Internet, and applications in optical data storage, quantum information and even radar. (U.K.)

  16. Gas storing and processing device

    International Nuclear Information System (INIS)

    Kobayashi, Yoshihiro; Takano, Yosoko.

    1988-01-01

    Purpose: To increase the gas injection processing performance and obtain stable accumulation layers by increasing the thickness of the accumulation layers of amorphous alloy. Constitution: The gas storing processing device comprises a cylindrical vessel constituting an outer cathode for introducing gases to be processed, an inner cathode in which transition metal material and rare earth metal material as a sputtering target disposed in the vessel are combined by way of insulating material, an anode cover disposed to the upper portion of the vessel and an anode bottom disposed at the bottom thereof. It is adapted such that DC high voltage sources are connected respectively to the outer and the inner cathodes and sputtering voltage can be applied, removed and controlled independently to the transition metal and the rare earth metal of the inner cathode. This enables to control the composition ratio of the accumulation layers of amorphous alloy formed to the surface of the outer cathode, thereby enabling operation related with the gas injection ratio. (Sekiya, K.)

  17. Regulation of glycogen synthase kinase-3 during bipolar mania treatment.

    Science.gov (United States)

    Li, Xiaohong; Liu, Min; Cai, Zhuoji; Wang, Gang; Li, Xiaohua

    2010-11-01

    Bipolar disorder is a debilitating psychiatric illness presenting with recurrent mania and depression. The pathophysiology of bipolar disorder is poorly understood, and molecular targets in the treatment of bipolar disorder remain to be identified. Preclinical studies have suggested that glycogen synthase kinase-3 (GSK3) is a potential therapeutic target in bipolar disorder, but evidence of abnormal GSK3 in human bipolar disorder and its response to treatment is still lacking. This study was conducted in acutely ill type I bipolar disorder subjects who were hospitalized for a manic episode. The protein level and the inhibitory serine phosphorylation of GSK3 in peripheral blood mononuclear cells of bipolar manic and healthy control subjects were compared, and the response of GSK3 to antimanic treatment was evaluated. The levels of GSK3α and GSK3β in this group of bipolar manic subjects were higher than healthy controls. Symptom improvement during an eight-week antimanic treatment with lithium, valproate, and atypical antipsychotics was accompanied by a significant increase in the inhibitory serine phosphorylation of GSK3, but not the total level of GSK3, whereas concomitant electroconvulsive therapy treatment during a manic episode appeared to dampen the response of GSK3 to pharmacological treatment. Results of this study suggest that GSK3 can be modified during the treatment of bipolar mania. This finding in human bipolar disorder is in agreement with preclinical data suggesting that inhibition of GSK3 by increasing serine phosphorylation is a response of GSK3 to psychotropics used in bipolar disorder, supporting the notion that GSK3 is a promising molecular target in the pharmacological treatment of bipolar disorder. © 2010 John Wiley and Sons A/S.

  18. A theoretical study of stability and vacancy replenishing of MoO{sub 3}(0 1 0) surfaces in oxygen atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Yan-Hua; Chen, Zhao-Xu, E-mail: zxchen@nju.edu.cn

    2016-01-15

    Graphical abstract: - Highlights: • Under normal experimental conditions perfect surface of MoO{sub 3}(0 1 0) is favorable. • Line defects along asymmetric oxygen direction in lean oxygen condition are favored. • Vacancy replenishing occurs on vacancies formed by terminal and asymmetrical oxygen. - Abstract: Oxygen vacancies on transition metal oxide surfaces are catalytically very important. The stability, shape and replenishing process of the vacancies are critical to understanding reactions happening on the surfaces. In this paper we investigate the stability of various defective MoO{sub 3}(0 1 0) surfaces and examine the influence of environmental oxygen on the stability as well as the active sites for the replenishing process. Our calculations reveal that the line oxygen defect along a (asymmetric oxygen) direction is thermodynamically most favorable at higher defect concentration whereas point defect surfaces are unfavorable. Under normal experimental conditions the perfect surface dominates the MoO{sub 3}(0 1 0). We show that for stoichiometric surfaces of any oxides (A{sub x}O{sub y}) the formation energy per vacancy controls the favorable defect shape (line or point defects). Calculations indicate that O{sub 2} can dissociate readily on the surfaces that double vacancies share one Mo atom. The replenishing process of the oxygen vacancies through O{sub 2} dissociation most likely occurs on the double-vacancy containing one terminal and one asymmetrical oxygen vacancies.

  19. Local depletion of glycogen with supra-maximal exercise in human skeletal muscle fibres

    DEFF Research Database (Denmark)

    Gejl, Kasper Degn; Ørtenblad, Niels; Andersson, Erik

    2017-01-01

    importance to muscle function. The present study was designed to investigate the depletion of these three sub-cellular glycogen compartments during repeated supra-maximal exercise in elite athletes. Ten elite cross-country skiers (age: 25 ± 4 yrs., VO2 max : 65 ± 4 ml kg(-1) min(-1) , mean ± SD) performed...... four ∼4-minute supra-maximal sprint time trials (STT 1-4) with 45 min recovery. The sub-cellular glycogen volumes in m. triceps brachii were quantified from electron microscopy images before and after both STT 1 and STT 4. During STT 1, the depletion of intramyofibrillar glycogen was higher in type I...... fibres (-52% [-89:-15%]) than type 2 fibres (-15% [-52:22%]) (P = 0.02), while the depletion of intermyofibrillar glycogen (main effect: -19% [-33:0], P = 0.006) and subsarcolemmal glycogen (main effect: -35% [-66:0%], P = 0.03) was similar between fibre types. In contrast, only intermyofibrillar...

  20. Pivotal role of glycogen synthase kinase-3: A therapeutic target for Alzheimer's disease.

    Science.gov (United States)

    Maqbool, Mudasir; Mobashir, Mohammad; Hoda, Nasimul

    2016-01-01

    Neurodegenerative diseases are among the most challenging diseases with poorly known mechanism of cause and paucity of complete cure. Out of all the neurodegenerative diseases, Alzheimer's disease is the most devastating and loosening of thinking and judging ability disease that occurs in the old age people. Many hypotheses came forth in order to explain its causes. In this review, we have enlightened Glycogen Synthase Kinase-3 which has been considered as a concrete cause for Alzheimer's disease. Plaques and Tangles (abnormal structures) are the basic suspects in damaging and killing of nerve cells wherein Glycogen Synthase Kinase-3 has a key role in the formation of these fatal accumulations. Various Glycogen Synthase Kinase-3 inhibitors have been reported to reduce the amount of amyloid-beta as well as the tau hyperphosphorylation in both neuronal and nonneuronal cells. Additionally, Glycogen Synthase Kinase-3 inhibitors have been reported to enhance the adult hippocampal neurogenesis in vivo as well as in vitro. Keeping the chemotype of the reported Glycogen Synthase Kinase-3 inhibitors in consideration, they may be grouped into natural inhibitors, inorganic metal ions, organo-synthetic, and peptide like inhibitors. On the basis of their mode of binding to the constituent enzyme, they may also be grouped as ATP, nonATP, and allosteric binding sites competitive inhibitors. ATP competitive inhibitors were known earlier inhibitors but they lack efficient selectivity. This led to find the new ways for the enzyme inhibition. Copyright © 2015 Elsevier Masson SAS. All rights reserved.