Insulin receptor binding and insulin-mediated glucose uptake in type-II-diabetics.

A 5-hour insulin clamp was performed in 7 normal subjects (N) and 6 type-II-diabetics. After a 10-min-priming insulin infusion, a constant infusion of 1.813 micrograms/m2 s.

In vivo evaluation in intrathyroidal iodide metabolism.

A new coincidence counting method is used to measure absolute thyroid 125I activity with accurate correction of extrathyroidal neck activity. Data collected are analyzed according to a three-compartment model, giving parameters both dependent and independent of plasma iodide concentration. Iodide is postulated to form a complex with the iodide trap before it is transported and organified.

Effect of age on glucose tolerance, insulin secretion, and in vivo insulin action.

The effect of age on glucose tolerance, insulin secretion, and in vivo insulin action (insulin clamp) was studied in 48 nonobese subjects, all of whom were fully ambulatory and in good general health. The observed age-related increase in fasting plasma glucose (r = 0.35, P less than 0.

Lipid metabolism in non-insulin-dependent diabetes mellitus: effect of glipizide therapy.

Plasma lipid concentration and lipoprotein composition were studied before and after several months of glipizide treatment in 23 patients with non-insulin-dependent diabetes mellitus. The mean (+/- SEM) plasma glucose level fell 87 mg/dL, and the fall in plasma glucose concentration was correlated with a reduction in plasma triglyceride, very low-density lipoprotein triglyceride, cholesterol, and low-density lipoprotein cholesterol levels. Furthermore, there was a statistically significant increase in the plasma high-density lipoprotein cholesterol to total cholesterol ratio.

Does insulin removal rate from plasma decline with age?

The effect of age on the rate of insulin removal from plasma was studied in both rat and man. The experimental approach was based on measurement of the steady-state plasma insulin concentration achieved during a period in which endogenous insulin secretion was suppressed and exogenous insulin infused. Rats, 1 1/2 and 12 mo of age, were infused with 2.

Effect of variations in basal plasma glucose concentration on glucose utilization (M) and metabolic clearance (MCR) rates during insulin clamp studies in patients with non-insulin-dependent diabetes mellitus.

Two insulin clamp studies were performed at different steady-state plasma glucose concentrations in 13 patients with non-insulin-dependent diabetes mellitus (NIDDM). Steady-state plasma insulin concentrations were comparable, with mean +/- SEM levels of 94 +/- 3 and 95 +/- 4 muU/ml being achieved during the two studies. Glucose utilization rate (M) varied directly with plasma glucose concentration in each subject.

Comparison of insulin secretion and in vivo insulin action in nonobese and moderately obese individuals with non-insulin-dependent diabetes mellitus.

Insulin secretion and in vivo insulin action were quantified in nonobese and moderately obese patients (approximately 30% overweight) with non-insulin-dependent diabetes mellitus (NIDDM), matched for severity of diabetes. Insulin secretion was assessed by determining plasma insulin responses to a test meal given at noon, and in vivo insulin action by the insulin clamp technique. No significant differences were noted between the two groups for either variable.

Effect of sulfonylurea treatment on in vivo insulin secretion and action in patients with non-insulin-dependent diabetes mellitus.

The effect of glipizide treatment on diabetic control and on in vivo insulin secretion and action was studied in 20 patients with non-insulin-dependent diabetes mellitus (NIDDM). Patients were examined before and after a minimum of 3 mo treatment. Mean (+/- SEM) fasting plasma glucose level fell from 264 +/- 12 mg/dl to 172 +/- 10 mg/dl (P < 0.

The measurement of trabecular bone mineral density using coherent and Compton scattered photons in vitro.

A photon scattering method for measuring the trabecular bone mineral density (TBMD) in vitro is described. This method involves the measurement of the ratio of coherent to Compton 90 degrees scattered photons from Am-241 by using a narrow beam geometry with an intrinsic germanium detector. The feasibility of using smaller scattering angles for better counting efficiency and the associated problems in their application for in-vivo measurements were investigated.

Effects of moderate increases in dietary polyunsaturated: saturated fat on plasma triglyceride and cholesterol levels in man.

1. The effects of two isoenergetic diets differing only in the values for polyunsaturated: saturated fat (P:S values of 0.2 v.

A dose table describing fractions of peripheral volume for 125I volume implants.

A dose table that provides the dose as a function of fractions of peripheral volume for 125I implants is presented. The table is based on seed distributions from 50 actual patient implants. Computer dosimetry was used to determine peripheral doses and dose ranges within implant volumes.

Effect of differences in source of dietary carbohydrate on plasma glucose and insulin responses to meals in patients with impaired carbohydrate tolerance.

Two test meals, varying only in type of carbohydrate foods, were given to 12 volunteers with impaired glucose tolerance. The carbohydrate content of one meal was composed of potato and gelatin, while the other meals contained an equivalent amount of carbohydrate as rice and corn. The two meals were otherwise identical, and the additional constituents were turkey, green salad, and salad dressing.

The impact of autonomic nervous system dysfunction on breathing during sleep.

Ten patients with autonomic nervous system dysfunction (familial dysautonomia, juvenile diabetes, or Shy-Drager syndrome) were studied to assess the impact of their impairment on breathing during sleep. Several types of breathing dysfunction during sleep were identified independent of the patients' primary complaints. Obstructive sleep apnea syndrome was the most common; central sleep apnea and disturbances of te respiratory oscillator also were seen.

Assessment of insulin resistance with the insulin suppression test and the euglycemic clamp.

Insulin resistance was quantified with two different methods in 30 subjects with varying degrees of glucose tolerance. One method, the insulin suppression test, is performed by continuously infusing epinephrine, propranolol, insulin, and glucose. Epinephrine and propranolol suppress endogenous insulin release, and steady-state plasma levels of exogenous insulin and glucose are reached in all individuals.

Measurement of the velocity of ultrasound in human cortical bone in vivo. Estimation of its potential value in the diagnosis of osteoporosis and metabolic bone disease.

Using a method combining the velocity of ultrasound and photon absorptiometry in the human radius in vivo, the authors measured the speed of sound in bone (U) and bone mineral content (BMC). From these measurements and a "simple" bone model, they then computed the bone mineral density, compact bone density, and modulus of elasticity. The accuracy of these parameters and of the bone model is assessed, and normal values for each parameter are given and compared with published values.

Simultaneous determination of free thyroxine and capacity of thyroxine-binding globulin.

A simple method is described for the simultaneous determination of capacity thyroxine-binding of globulin (TBG) and free thyroxine concentration (FT4). The ratio of bound to free T4 (B/F) is first determined for two total-T4 concentrations using a Sephadex G-25 competitive-binding technique. TBG capacity and FT4 can both the calculated assuming a known value of affinity constant of TBG.

Relationship between insulin resistance, insulin secretion, very low density lipoprotein kinetics, and plasma triglyceride levels in normotriglyceridemic man.

We have previously postulated that resistance to insulin-mediated glucose uptake was the basic metabolic abnormality in patients with endogenous hypertriglyceridemia. In this situation, glucose tolerance would tend to deteriorate, and could only be maintained by the increased secretion of insulin. Although the ensuing hyperinsulinemia might prevent the development of glucose intolerance, we suggested that it would also lead to increased hepatic very low density (VLDL) triglyceride (TG) synthesis and secretion.

Diabetic hypertriglyceridemia: evidence for three clinical syndromes.

Based on studies of both man and rat, it is proposed that at least three distinct syndromes of hypertriglyceridemia occur as the result of abnormalities of carbohydrate metabolism. We believe that these syndromes are the predictable results of the changes in plasma insulin and/or free fatty acid (FFA) concentration that occur in patients with impaired glucose tolerance (IGT), non-insulin-dependent diabetes mellitus (NIDDM), and insulin-dependent diabetes mellitus (IDDM). In patients with IGT the basic defect is postulated to be loss of normal insulin sensitivity, leading to compensatory hyperinsulinism, increased very low density lipoprotein (VLDL)-triglyceride (TG) secretion, and hypertriglyceridemia.

A new method of calculating absolute thyroid activity in intravenous I-123 uptake tests.

A technique for determining the absolute activity of I-123 in early thyroidal uptake tests is presented. The method is independent of geometry, tissue attenuation, an extrathyroidal neck activity (ENA). It utilizes the efficiency factors (ExT and E gamma T) derivable for the thyroid gland using coincidence counting techniques, and a quantity, alpha, characteristics of the vascularity of the individual patient.

Effect of age on plasma triglyceride concentrations in man.

Plasma triglyceride (TG) concentrations increase with advancing age. To determine if this phenomenon is due to age per se or to age-related changes in other metabolic variables, determination of fasting plasma TG, glucose, insulin, and free fatty acid (FFA) concentrations, as well as body mass index (BMI), were made on 167 normal subjects from 18 to 77 yr of age. Significant simple correlation coefficients (r) were found between TG concentrations and age (0.

Accuracy of bone mineral data.

The reliability of data obtained from the Norland-Cameron Bone Mineral Analyzer has been questioned and the possibility of an inherent calibration error in the machine has been raised. To make an absolute measurement of the instrumental accuracy, bone mineral content measured by the bone mineral analyzer was compared with an absolute value obtained by the ashing method. The instrument bone mineral content values were found to be higher by about 6.

Measurement of the velocity of ultrasound in the human femur in vivo.

A pulse-echo technique for measuring the velocity of ultrasound in the cortex of the femur in vivo is presented. The average result for 27 asymptomatic volunteers is 3250 +/- 190 m/s. The results show no significant differences between proximal and distal femoral sites, right and left femora, males and females.