Glucose utilization rates

Based on glucose utilization rate after subcutaneous administration. 

The steady-state maternal glucose utilization rate can be calculated for a normal maternal glucose concentration of 120 mg % from the rate at which glucose diffuses into the placental tissue at steady state. This is given by ... 

Horwitz, B., Swedo, S.E., Grady, C.L., Pietrini, P., Schapiro, M.B., Rapoport, J.L., and Rapoport, S.I. (1991) Cerebral metabolic pattern in obsessive-compulsive disorder altered intercorrelatlons between regional rates of glucose utilization. Psychiatry Res 40 221-237. 

It is a sympathomimetic amine, the mechanism of action is related to brain levels (or turnover rates) of serotonin or to increase glucose utilization. Its antiappetite effect is suppressed by serotonin blocking drugs. Its use in clinical practice is recently banned in India because of severe toxicity. 

Initially the reactor was fed at 92 mL/h (dilution rate of 0.29 Ir1) with P2 medium until there were visible signs of cell mass accumulation. It took about 5 d to accumulate cell mass and for the reactor to be productive. The flow rate was then increased to 100 mL/h, and the reactor was allowed to achieve a new steady state. At this stage, a control experiment was run and the reactor was fed with P2 medium. At this dilution rate (0.32 h1), the reactor produced 6.86 g/L of total ABE and 2.36 g/L of total acids (Table 1). This resulted in an ABE productivity of 2.19 g/(Lh) and a yield of 0.27. This productivity is manyfold higher than the productivity achieved in a batch reactor (0.38 g/[L h]) (10). Glucose utilization was 39.1% of that available in the feed (65.5 g/L). In these reactors, high productivity is achieved but at the expense of a low ABE concentration in the effluent as well as low sugar utilization. To improve sugar utilization, the reactor effluent should be recycled back to the reactor after ABE removal (11). 

Next, an experiment was run in which 2.5 g/L of sodium butyrate was added to P2 medium to investigate whether it could be converted to butanol. A control experiment was run containing P2 medium. A separate control experiment was run before each experiment. This is essential because biomass accumulation in the reactor changes with time, thus affecting performance of the reactor (5). The reactor produced 4.77 g/L of total ABE, of which acetone, butanol, and ethanol were 1.51,3.14, and 0.12 g/L, respectively (Table 1). It resulted in a total ABE productivity of 1.53 g/(L-h) and a glucose utilization of 29.4% of that available in the feed of 59.1 g/L. The acid concentration in the effluent was 1.56 g/L. Following this, P2 medium was supplemented with sodium butyrate and the experiment was conducted at the same dilution rate. The reactor produced 1.55 g/L of acetone, 4.04 g/L of butanol, and 0.11 g/L of ethanol, for a total ABE concentration of 5.70 g/L, compared with 4.77 g/L in the control experiment. The productivity was 1.82 g/(L-h), compared with 1.53 g/(L-h) for the control experiment. These experiments suggested that butyrate was used by the culture to produce additional butanol. Note that 0.9 g/L of butanol was produced from 1.65 g/L of butyrate (2.5 g/L in feed, 0.85 g/L in effluent). The yield calculations do not include the amount of butyrate that was utilized by the culture. 

Although the researchers do not discuss it, reduced glucose utilization would produce the reduced metabolic rate and hypoactivity in the frontal lobes caused by neuroleptics, causing or contributing to their brain-disabling, lobotomy-like effect. And they fall prey to wishful thinking, imagining that the abnormal proliferation of neural cells stimulated by olanzapine may be therapeutic. 

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