C-glucose

Synthetic chemical approaches to the preparation of carbon-14 labeled materials iavolve a number of basic building blocks prepared from barium [ CJ-carbonate (2). These are carbon [ C]-dioxide [ CJ-acetjlene [U— C]-ben2ene, where U = uniformly labeled [1- and 2- C]-sodium acetate, [ C]-methyl iodide, [ C]-methanol, sodium [ C]-cyanide, and [ CJ-urea. Many compHcated radiotracers are synthesized from these materials. Some examples are [l- C]-8,ll,14-eicosatrienoic acid [3435-80-1] inoxn. [ CJ-carbon dioxide, [ting-U— C]-phenyhsothiocyanate [77590-93-3] ftom [ " CJ-acetjlene, [7- " C]-norepinephrine [18155-53-8] from [l- " C]-acetic acid, [4- " C]-cholesterol [1976-77-8] from [ " CJ-methyl iodide, [l- " C]-glucose [4005-41-8] from sodium [ " C]-cyanide, and [2- " C]-uracil [626-07-3] [27017-27-2] from [ " C]-urea. All syntheses of the basic radioactive building blocks have been described (4). 

Saccharomyces cerevisiae is anaerobically grown in a continuous culture at 30°C. Glucose is used as substrate and ammonia as nitrogen source. A mixture of glycerol and ethanol is produced. At steady-state condition mass the flow rate is stated. The following reaction is proposed for the related bioprocess 4,6... 

Duckworth WC, McCarren M, Abraira C. Glucose control and cardiovascular complications the VA diabetes trial. Diabetes Care 2001 24(5) 942-5. 

The binding specificity of d-[ C]glucose by the taste-papillae membranes, compared to that of control membranes isolated from epithelial tissue, has been confirmed in two studies. One inherent problem in the approach is that the stimuli, primarily carbohydrate sweeteners, are not ideal model compounds to use, as they are not active at low concentrations and do not show sufficiently high binding-constants. The use of other stimulus compounds that are at least several hundred times sweeter than sucrose, such as saccharin, dihydrochalcone sweeteners, dipeptide sweeteners, stevioside, perillartine and other sweet oximes, the 2-substituted 5-nitroanilines, and... 

FIGURE 9.3 Active carbon substrate SALDI mass spectra of (a) DL-lysine (1.8 nmol), (b) caffeine (0.5 nmol), and (c) glucose (3.19 nmol). Solutions of these compounds were pipetted directly onto an active carbon substrate patch. (From Han, M. and Sunner J., J. Am. Soc. Mass Spectrom., 11, 644-649, 2000. With permission.)... 

Figure 46.5. Experiment B Results, Molar composition after 3 h at 100°C (glucose not present during ran).

London et al. (1988a, b) Rats 2-Deoxy-D- [l- C]glucose autoradiography SC nic (0.1-1.75 mg kg- ) t Nicotine rich regions, including thal, cereb, visual system, others... 

Marenco et al. (2000) Rats - chronically nic exposed vs, nic naive 2-Deoxy-D-[l- C] glucose autoradiography SC nic (0.4 mg kg- ) vs. saline t Thai, superior colliculus in chronically exposed f thal, superior colliculus, medial habenula, and dorsal lateral geniculate in nic naive... 

All assays performed on digester samples were conducted in 100 mM Tris buffer pH 7.5 with substrate incubations at 37 C. Glucose-releasing assays used the same Tris buffer with 0.5% sodium azide added. Colorimetric products from enzyme assays were detected and recorded using a Milton-Roy model 601 spectrophotometer equipped with sipper and data printer. 

Fig. 2. Experimental design of a C tracer experiment for the determination of the flux partitioning ratio between pentose phosphate pathway and glycolysis ( ppp) C label distribution from l- C glucose through the network with C atoms (black) and C atoms (white)...

Studies of mammals subjected to SCN destruction and transplantation have revealed that the hypothalamic SCN contains a master circadian oscillator which is involved in a number of behaviours and hormonal secretions. The circadian oscillatory activity of SCN neurons is directly demonstrated by the measurement of [ " C] glucose metabolic activity and field potentials assessed by electro-physiological devices. The clock oscillatory genes mPer1 and mPer2 are expressed rhythmically in most neurons in the SCN. Thus, thousands of clock cells in the SCN might generate the rhythm. 

---