Controlled glucose pulses

Fig. 6.4 Temporal behavior of the normalized signal S when a glucose pulse is applied, increasing the glucose from 5 mM to 10 mM and lasting for 60 min. The PI control features are clearly seen, starting with a rapid proportional response, followed by a slow integral control. Increasing the time constant k-, responsible for the integral control, results in a faster saturation of the response. The smallest and maximal value of the active fraction is Xq = 0.2 and Xmax = 0-8 respectively.

In 7 healthy subjects pretreatment with oral theophylline for at least 4 days significantly increased the fall in serum potassium levels and rises in blood glucose, pulse rate, and systolic blood pressure caused by an infusion of terbutaline. A study in children given slow-release formulations of both theophylline and terbutaline found no increases in reported adverse effects and simple additive effects on the control of their asthma. ... 

Figure 37 Heat flow rate and total heat released during controlled fed-batch culture of Saccharopolyspora erythraea by pulsing glucose after ammonium depletion of the culture shown in Figure 36. The depletion of glucose was easily detected by the sharp heat flow rate decrease immediately followed by the injection of a glucose pulse. (Redrawn from Reference [81] with permission of the author and publisher).

G Albin, TA Horbett, BD Ratner. Glucose-sensitive membranes for controlled release of insulin. In J Kost, ed. Pulsed and Self-Regulated Drug Delivery. Boca Raton, FL CRC Press, 1990, pp 159-185. 

Protoplasts obtained from cells pulse-labeled with either [U-i C]glucose or [U- C] mannose were lysed and treated with puromycin. The antibiotic-treated cells showed a drop in the radioactivity associated with the polysomes and the absorbancy at 254 nm was also lower than the control. 

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