OBJECTIVE To quantitate the separate impact of obesity and hyperglycemia on the incretin effect (i.e., the gain in beta-cell function after oral glucose versus intravenous glucose). RESEARCH DESIGN AND METHODS Isoglycemic oral (75 g) and intravenous glucose administration was performed in 51 subjects (24 with normal glucose tolerance [NGT], 17 with impaired glucose tolerance [IGT], and 10 wit...

The minimal model method is widely used to estimate glucose effectiveness (S(G)) and insulin sensitivity (S(I)) from intravenous glucose tolerance test (IVGTT) data. In the standard protocol (sIVGTT, 0.33 g/kg glucose bolus given at time 0), which allows the simultaneous assessment of beta-cell function, the precision of the individualized estimates often degrades and particularly so in the pre...

1. Blood pyruvate and lactate levels during oral and intravenous glucose tolerance tests are described in obese and non-obese non-diabetic, maturity-onset diabetic and insulin-requiring diabetic groups of women. 2. Mean fasting blood pyruvate levels were similar in non-diabetic, maturityonset diabetic and insulin-requiring diabetic subjects of similar degree of obesity. Mean levels were higher ...

Seven non-diabetic patients with chronic pancreatitis were shown to have a diminished acute insulin secretory response after intensive beta cell and intravenous tolbutamide stimulation. In an attempt to unmask their 'latent' diabetic state, triamcinolone-augmented glucose tolerance tests were performed some days after documenting normal standard 50 g oral glucose tolerance tests. A matched grou...

The simultaneous assessment of quantitative indexes of insulin secretion and action in a single individual is important when quantifying their relative role in the evolution of glucose tolerance in different physiopathological states. Available methods quantify these indexes in relatively nonphysiological conditions, e.g., during glucose clamps or intravenous glucose tolerance tests. Here, we p...

Andrews, J. S., Boyd, H. M. & Terry, D. E. [1942]. Cereal Chem. 19, 55. Barton-Wright, E. [1942]. Nature, Lond., 149, 696. Birch, T. W. & Gyorgy, P. [1935]. Chem. Industr. 54, 507. Chick, H., Macrae, T. F. & Worden, A. N. [1940]. Biochem. J. 34, 580. Conger, T. W. & Elvehjem, C. A. [1941]. J. biol. Chem. 138, 555. Conner, R. T. & Straub, G. J. [1941a]. Indu8tr. Engng Chem. (Anal. ed.), 13, 385....