• Animal cells and systems
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• v.8 no.4
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• pp.307-312
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• 2004

Fast kinetics of transient pH changes and difference spectrum formation have been investigated following mixing of ADP/ATP with partially purified plasma membrane PM-ATPase of the pathogenic yeast Candida albicans in the presence of five nutrients: glucose, glutamic acid, proline, lysine, and arginine and two analogs of glucose: 2-deoxy D-glucose and xylose. Average $H^+$- absorption to release ratio, indicative of population of ATPase undergoing complete hydrolytic cycle, was found to be 0.27 for control. This ratio varied between 0.25 (proline) to 0.36 (arginine) for all other compounds tested, except for glucose. In the presence of glucose, $H^+$- absorption to release ratio was exceptionally high (0.92). While no UV difference spectrum was observed with ADP, mixing of ATP with ATPase led to a large conformational change. Exposure to different nutrients restricted the magnitude of the conformational change; the analogs of glucose were found to be ineffective. This suppression was maximal in the case of glucose (80%); with other nutrients, the magnitude of suppression ranged from 40-50%. Rate of $H^+$- absorption, which is indicative of E~P complex dissociation, showed positive correlation with suppression of conformational change only in the case of glucose and no other nutrient/analog. Mode of interaction of glucose with plasma membrane $H^+$-ATPase thus appears to be strikingly distinct compared to that of other nutrients/analogs tested. The results obtained lead us to propose a model for explaining glucose stimulation of plasma membrane $H^+$-ATPase activity.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.982-985
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• 2002

A study was carried out to determine glucose kinetics, nutrient balance and milk production of lactating Etawah crossbred goats. The animals (27.2 to 29.1 kg BW) were randomly divided into four levels of dietary treatment groups: the first group R1 received 100% (3 kg) fresh king grass (Penisetum purpuroides), the second group R2 received 75% king grass and 25% king grass silage prepared with chicken manure, the third group R3 received 50% king grass and 50% silage, and the fourth group R4 received 100% silage. In addition to the roughage, each group received 800 g of concentrate (CP 14.77% of DM; 17.26 MJ/kg). Animals fed king grass silage made with chicken manure were found to be superior to the group fed king grass alone. Glucose kinetics and retained energy were significantly affected. Calculations showed that glucose requirements for maintenance and milk production can be met for the groups with high levels of silage (R3 and R4). The values of glucose flux were in the range of 2.52 to 4.50 mg/min.kg $BW^{0.807}$ which are lower, but close to, the values for the temperate lactating dairy cow. The present glucose flux value for the lactating Etawah crossbred goat is higher than the previous value published from this laboratory.

• Journal of Biomedical Engineering Research
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• v.4 no.1
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• pp.9-14
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• 1983

A new quantitative method was developed for separation of three interactive physiological factors (hepatic glucose balance, peripheral tissue's insulin resistivity, and insulin secretion rate) influencing glucose intolerance in diabetic mellitus using an equivalent circuit model and the intravenous glucose tolerance test (IVGTT) in six dogs and twenty two humans. The results show that the estimated model parameters of the above three factors are useful for evaluating different glucose-insulin kinetics in normal and diabetic subjects.

• KSBB Journal
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• v.10 no.3
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• pp.323-334
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• 1995

The effects of glucose on cell growth kinetics, monoclonal antibody productivity, and cell metabolism or hybridoma cells were investigated. The mouse-mouse hybridoma cell line VIII H-8 producing mouse IgG2a was used as a modal system. Glucose showed substrate inhibition type dependence on specific growth raie. The maximum cell density increased as initial glucose concentration increased up to 4 g/$\ell$. Glucose showed a strong influence on cell death kinetics, and an inverse relationship between specific death rate and glucose concentration was found. Cell viability and monoclonal antibody production increased as initial glucose concentration increased. The specific glucose consumption rate increased with glucose concentration, and cumulative specific lactate production rate increased with increasing initial glucose concentration. The overall kinetics of ammonium ion production was almost invariant with respect to initial glucose concentration, while the cumulative specific ammonium ion production rate was dependent on initial glucose concentration.

• Journal of Biomedical Engineering Research
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• v.2 no.1
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• pp.31-38
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• 1981

The objective of the present study was to develop an equivalent circuit model of glucose kinetics including the hepatic glucose balance functions which were neglected in the previous compartmental models. Using this circuit model, the insulin resistivity parameter and hepatic glucose sensitivity parameter were estimated in optimal fitting of the model based data of glucose and insulin concentration to the reported clinical intravenous glucose tolerance test(IVGTT) data in normal and diabetic subjects. The addition of the hepatic function in the model has improved the overall performance of the simulation. Also, the computed tissue insulin resistivity and the hepatic glucose sensitivity are shown to be significant in distinguishin four clinical groups of normal and diabetic groups.

• Journal of Animal Science and Technology
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• v.59 no.6
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• pp.14.1-14.9
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• 2017

Background: Garlic and its constituents are reported to have been effective in reducing methane emission and also influence glucose metabolism in body; however, studies in ruminants using garlic leaves are scarce. Garlic leaves contain similar compounds as garlic bulbs, but are discarded in field after garlic bulb harvest. We speculate that feeding garlic leaves might show similar effect as garlic constituents in sheep and could be potential animal feed supplement. Thus, we examined the effect of freeze dried garlic leaves (FDGL) on rumen fermentation, methane emission, plasma glucose kinetics and nitrogen utilization in sheep. Methods: Six sheep were fed Control diet (mixed hay and concentrate (60:40)) or FDGL diet (Control diet supplemented with FDGL at 2.5 g/kg $BW^{0.75}$ of sheep) using a crossover design. Methane gas emission was measured using open-circuit respiratory chamber. Plasma glucose turnover rate was measured using isotope dilution technique of [$U-^{13}C$]glucose. Rumen fluid, feces and urine were collected to measure rumen fermentation characteristics and nitrogen utilization. Result: No significant difference in rumen fermentation parameters was noticed except for rumen ammonia tended to be higher (0.05 < P < 0.1) in FDGL diet. Methane emission per kg dry matter ingested and methane emission per kg dry matter digested were lower (P < 0.05) in FDGL diet. Plasma glucose concentration was similar between diets and plasma glucose turnover rate tended to be higher in FDGL diet (0.05 < P < 0.1). Nitrogen retention was higher (P < 0.05) and microbial nitrogen supply tended to be higher (0.05 < P < 0.1) in FDGL diet. Conclusion: FDGL diet did not impair rumen fermentation, improved nitrogen retention; while absence of significant results in reduction of methane emission, glucose turnover rate and microbial nitrogen supply, further studies at higher dose would be necessary to conclude the merit of FDGL as supplement in ruminant feedstuff.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.291-293
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• 2003

Batch reactors were employed to investigate the kinetics of cellulose hydrolysis under extremely low acid (ELA) and high temperature condition. The sawdust was pretreated by Auto-hydrolysis prior to the batch reaction. The maximum yield of glucose obtained from the batch reactor experiment was about 70% for the pretreated sawdust, this occurred at 210 and 22$0^{\circ}C$. The maximum glucose yield from the untreated sawdust was much lower at these temperatures, about 55%. The maximum yields of glucose from the lignocellulosics were obtained between 15th and 20th minutes after which gradual decrease was observed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.115-121
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• 2005

Using a general Saccharomyces cerevisiae as a model strain, continuous ethanol fermentation was carried out in a stirred tank bioreactor with a working volume of 1,500 mL. Three different gravity media containing glucose of 120, 200 and 280 g/L, respectively, supplemented with 5 g/L yeast extract and 3 g/L peptone, were fed into the fermentor at different dilution rates. Although complete steady states developed for low gravity medium containing 120 g/L glucose, quasi-steady states and oscillations of the fermented parameters, including residual glucose, ethanol and biomass were observed when high gravity medium containing 200 g/L glucose and very high gravity medium containing 280 g/L glucose were fed at the designated dilution rate of $0.027\;h^{-1}$. The observed quasi-steady states that incorporated these steady states, quasi-steady states and oscillations were proposed as these oscillations were of relatively short periods of time and their averages fluctuated up and down almost symmetrically. The continuous kinetic models that combined both the substrate and product inhibitions were developed and correlated for these observed quasi-steady states.

• Molecules and Cells
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• v.23 no.3
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• pp.272-279
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• 2007

The maintenance of normal blood glucose levels at rest and during exercise is critical. The maintenance of blood glucose homeostasis depends on the coordination and integration of several physiological systems, including the sympathetic nervous system and the endocrine system. During prolonged exercise increased demand for glucose by contracting muscle causes to increase glucose uptake to working skeletal muscle. Increase in glucose uptake by working skeletal muscle during prolonged exercise is due to an increase in the translocation of insulin and contraction sensitive glucose transporter-4 (GLUT4) proteins to the plasma membrane. However, normal blood glucose level can be maintained by the augmentation of glucose production and release through the stimulation of liver glycogen breakdown, and the stimulation of the synthesis of glucose from other substances, and by the mobilization of other fuels that may serve as alternatives. Both feedback and feedforward mechanisms allow glycemia to be controlled during exercise. This review focuses on factors that control blood glucose homeostasis during prolonged exercise.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.365-372
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• 2007

This study was conducted to determine effects of salinomycin (SL) on feeding-induced changes in glucose kinetics and blood VFA concentrations in sheep fed a high-roughage diet. Four sheep were fed the diet with or without 20 mg/kg diet of SL once daily for 21 d. Glucose entry and utilization rates were determined during the prefeeding and 3 h postfeeding periods, using a [$^{13}C_6$]glucose dilution method and non-steady state equations. Ruminal characteristics and concentrations of blood VFA, plasma glucose and insulin were also measured during the same periods. A feeding-induced increase in ruminal total VFA concentration tended to be inhibited (p<0.10) with SL, although ruminal pH was unaffected (p>0.10) with SL or by feeding. Salinomycin decreased (p<0.05) acetate proportion and increased (p<0.05) propionate proportion in the rumen, but did not modify these changes in response to feeding (p>0.10). A feeding-induced increase in blood acetate concentration was attenuated (p<0.05) with SL. Salinomycin tended to increase (p<0.10) blood propionate concentration without modifying its response patterns to feeding (p>0.10). Plasma concentrations of glucose or insulin were unaffected (p>0.10) with SL. Salinomycin tended to enhance (p<0.10) glucose entry and utilization rates. Feeding also enhanced (p<0.01) both rates, whereas their interactive effect was not detected (p>0.10). We conclude that SL possibly enhances whole body glucose entry and utilization with an increase in blood propionate concentration in sheep given a high-roughage diet, although SL does not appear to affect their responses to feeding.