Response to glucose

CF-related diabetes shares characteristics of both type 1 and type 2 diabetes mellitus but is categorized separately. The primary cause of CFRD is insulin deficiency resulting from both reduced functional pancreatic islet cells and increased islet amyloid deposition. Insulin secretion is delayed in response to glucose challenge, and absolute insulin secretion over time is reduced. Some insulin resistance may also be present in CFRD however, sensitivity may be increased in CF patients without diabetes.8... 

Measurement of Weight Loss of Insulin-Loaded Matrix In Response to Glucose... 

In their report the researchers describe a culturing technique that can turn mouse embryonic stem cells into cell clusters that resemble pancreatic islets. The clusters inner cells produced insulin, while outer cells produced glucagon and somatostatin, two other proteins typically synthesized by pancreatic cells. Most important, the embryonic stem cell-derived pancreas cells produce insulin in response to glucose, the fundamental role of beta cells that regulate insulin secretion. The major shortcoming of the system at this time is the low levels of insulin production. Refinements in culture technique or drug manipulation may be needed to achieve therapeutic levels. 

Progesterone has little effect on protein metabolism. It stimulates lipoprotein lipase activity and seems to favor fat deposition. The effects on carbohydrate metabolism are more marked. Progesterone increases basal insulin levels and the insulin response to glucose. There is... 

Phenytoin rarely causes hyperglycemia, and the blood glucose concentration can increase in phenytoin intoxication (SED-13, 139) (115). A reduction in the insulin response to glucose has been noted with therapeutic... 

Several peptide products used in the treatment of diabetes mellitus, in addition to insulin, are currently administered by subcutaneous injection and these drugs are candidates for development of nasal formulations. Glucagon-like peptide-1 (GLP-l)-related peptides stimulate the insulin response to glucose and diminish the release of glucagon after a meal. These effects diminish the excessive postprandial increase in glucose observed after a meal in persons with type 2 diabetes mellitus. GLP-1-related peptides must be administered by subcutaneous injection before meals in order to be effective. This requirement for injection before each meal is likely to impact the utilization of these products by persons with type 2 diabetes. Exendin-4 is a GLP-1-related peptide with a molecular mass of 4.2 kDa. The development of a GLP-1-related peptide nasal formulation containing an absorption enhancer would allow patients to scll-administer one of these drugs just before a meal without the need for a subcutaneous injection. 

The selective response to glucose in this PCSA plot indicates that the PLS calibration model is selective for glucose and unaffected by the spectral features of sucrose and maltose. In terms of the spectra, this selectivity implies that the quantitative measurements are based on the NAS for glucose relative to sucrose and maltose. In this way, the calibration model is orthogonal to the spectral features of both sucrose and maltose. Indeed, Figure 13.8 shows the PLS calibration vector superimposed on the calculated NAS for glucose relative to sucrose and maltose. These vectors overlap, which indicates that the PLS calibration vector corresponds to the NAS, thereby defining the chemical basis of selectivity for this case. 

Glucose measurement The amperometric response to glucose was evaluated in a deaerated 0.1 M phophate buffer solution under mild stirring conditions. Prior to glucose measurement, the enzyme electrode was potentiostated at 0.7 V for 1 min and an appropriate aliquot of the stock solution of glucose was added to the buffered solution. The reading was taken at steady state. 

It is clear from these KMapp values, and from the glucose calibration curves, that the response of the sensors begins to deviate from linearity even at glucose concentrations below 10 mM (the response to glucose is expected to be strictly linear for concentrations approximately less than or equal to 0.1KMapp). We have previously... 

Electrochemical Behavior, Catalytic Response to Glucose, and Selectivity to Pharmaceutical Drugs... 

Effect of pH. The relationship between the catalytic current of a PPy-GOD film (2000 A) and the pH of the solution was recorded in the pH range of 3-11. When the pH was less than 3, no catalytic current was observed, but the current was increased by increasing the pH from 3 to 7. When pH was more than 7.5, the current decreased. The PPy-GOD film electrode showed a good catalytic response to glucose in the solutions of pH ranging between 6 and 8. 

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