[Preventive iodine administration and iodine excretion in the Vienna area and in the forest quarter].

In order to reduce the still substantial iodine deficiency in the Austrian population, compulsory iodisation of salt was increased in 1990 from 10 mg potassium iodide/kg salt to 20 mg potassium iodide/kg. In this investigation we evaluated the adequacy of iodine supply in Vienna and the Waldviertel, a rural region northwest of Vienna. Daily iodine excretion (which reflects daily iodine intake) was investigated in 92 persons from the Waldviertel (all without thyroid gland pathology) and 110 persons from Vienna (54 with unremarkable thyroid glands, 56 with endemic goiter).

Blood glucose response to stress hormone exposure in healthy man and insulin dependent diabetic patients: prediction by computer modeling.

To establish a qualitative and quantitative model of blood glucose response to stress hormone exposure, healthy subjects (HS) on and off somatostatin (250 micrograms/h) as well as insulin dependent diabetic patients were infused with either epinephrine (E), glucagon (G), cortisol (F), growth hormone (GH) or with a cocktail of these hormones raising plasma stress hormones to values seen in severe diabetic ketoacidosis. The developed input/output model consists of two submodels interconnected in series plus two additional submodels for correction of gains describing both sensitivity of tissue response and utilisation as well as provision of glucose. It was shown and confirmed experimentally that blood glucose response to stress hormones was essentially nonlinear.

Effect of stress hormones on transsplanchnic balance of exogenous amino acid in healthy man.

The effect of stress hormones on transsplanchnic balance of basal and infused amino acids (AA: Val,Met,Ile,Leu,Phe,Lys,His) was investigated in healthy men without and with added epinephrine (EPI) and dexamethasone (DEX). Concentrations of AA and blood glucose were measured in arterial and hepatic venous blood before and after primed-continuous (t = 120 minutes) AA infusion without (group I: controls; n = 6, 24 +/- 3 years), and with intravenous (IV) EPI infusion (group II: 6 micrograms/min, t = -75 to 120 minutes; n = 6, 26 +/- 5 years) or oral DEX pretreatment (group III: 6 mg/d for 2 days; n = 7, 26 +/- 3 years). In the absence of exogenous AA, EPI was demonstrated to increase estimated hepatic plasma flow (EHPF, mL/min: 1,019 +/- 133 [mean +/- SD] v 737 +/- 153; P less than .

Quantitative and qualitative differences in basal and glucose- and arginine-stimulated insulin secretion in healthy subjects and different stages of NIDDM.

To determine quantitative and qualitative differences in insulin secretion equimolar amounts of glucose and arginine were infused in 9 healthy subjects, in 8 individuals each with obesity without and with impaired glucose tolerance, and in non-obese and obese non-insulin-dependent diabetic patients (NIDDM). Insulin secretion was calculated after individual determination of metabolic clearance rate of C-peptide (MCRcp) both as the area under the C-peptide concentration curve times MCRcp, and by a mono-compartment mathematical model, both yielding identical results. MCRcp fell consistently with increasing C-peptide infusion rate (e.

The diuretic and natriuretic action of human atrial natriuretic peptide in humans: lack of effect of exogenous insulin.

The interaction of exogenous, synthetic human atrial natriuretic peptide [(hANP) (ANF 99-126)] and of exogenous insulin was investigated in six healthy men and in seven type I diabetic patients using the euglycemic clamp technique. A primed-continuous (1.0 mU/kg x min) infusion of biosynthetic human insulin was administered to acutely raise and maintain plasma insulin concentrations at approximately 75 to 100 microU/mL during four hours while plasma glucose concentrations were maintained constant at the fasting level by a variable infusion of glucose.

Effect of hyperosmolality on basal and hormone-stimulated hepatic glucose metabolism in vitro.

To understand better impairment of glucose utilization in diabetics during a hyperosmolal state, in vitro models were established to evaluate the effects of hyperosmolality on basal glucose uptake as well as glucagon dependent glucose release by isolated hepatocytes. In these studies simulating a hyperglycaemic (40 mmol glucose) and hyperosmolal (up to 500 mosm kg-1, NaCl as added solute) state basal hepatic glucose uptake was reversibly suppressed by 19% when osmolality was increased by as little as 10 mosm kg-1. No such effects on glucose uptake by isolated hepatocytes could be attained when the incubation's fluid osmolality was augmented by the addition of urea or mannitol.

[The status of managing the type I diabetic patient in Austria. Organization].

During the Annual Meeting of the Austrian Diabetes Association various diabetic centres presented their success and failure rates with respect to metabolic control and prevention of late complications in diabetic patients on a country-wide basis. The analysis revealed that only 30% of all type I diabetic patients are adequately controlled. Intensive education in diabetes self-management, capable of leading to optimal metabolic control in up to 50% of the instructed patients, is however available only to a small minority of the diabetic patients to date.

[Conventional or functional insulin therapy?].

The main difference between "conventional" and "functional" insulin replacement is that the former requires meals to be taken at set times throughout the day to avoid hypoglycaemic insulin reactions, while the latter separates insulin replacement in the basal ("fasting") state from that required with food intake. Such strategy reverses conventional insulin treatment (namely balancing the action of administered insulin by a fixed dietary intake), by substitution with a functional control of hyperglycaemia on the basis of tailored insulin doses. To this end blood glucose self control and systemic blood glucose correction are a must during functional insulin substitution, but not necessarily so during conventional insulin therapy.

Detrimental effect of hyperosmolality on insulin-stimulated glucose metabolism in adipose and muscle tissue in vitro.

To better understand impairment of glucose utilization in diabetics during a hyperosmolal state, in vitro models were established to evaluate the interdependence of hyperosmolality on basal as well as insulin-dependent glucose uptake by rat epididymal fat pads and diaphragms. Using the epididymal fat pad it was shown that NaCl and urea induced hyperosmolality of 400 and 500 mOsm/kg diminished insulin-stimulated glucose uptake by 35 and 90%, as well as 29 and 68%, respectively. Using rat diaphragm as target tissue for insulin action instead a transient rise in basal (non-insulin-dependent) glucose uptake was seen at 400 but not at 500 mOsm/kg.

[Proteinuria in diabetes mellitus].

A third of all Type 1 diabetic patients will develop proteinuria as a clinical sign of diabetic nephropathy. A 100-fold increase in relative mortality is observed in patients with persistent proteinuria. Proteinuria is preceded by a microproteinuric phase, which is reversible upon optimized metabolic control.

Effect of verapamil on basal and glucagon-dependent splanchnic glucose metabolism and insulin secretion in man.

To determine the effect of verapamil on basal and glucagon-induced changes in splanchnic glucose metabolism and insulin secretion, six healthy men were studied during a primed-continuous infusion of verapamil (2.5 micrograms/kg/min). After a basal period of 30 min, glucagon was infused at a rate of 12 ng/kg/min for an additional 60 min.

[Hepatic vein catheter technic: method for the detection of metabolic and hormonal variables in the splanchnic area].

The hepatic venous catheterization method permits calculation of net splanchnic output and uptake of substrates and hormones from their respective differences in hepatic venous and arterial concentrations as well as the rate of hepatic plasma or blood flow. Estimates of the latter are made possible by the continuous infusion technique using indocyanine green dye. With determination of splanchnic balance data at hand transsplanchnic and in part even transphepatic handling of metabolic substrates and hormones can be calculated.

[Hepatic and peripheral insulin resistance as a cause of hyperglycemia in non-insulin-dependent (type 2) diabetes mellitus: a review].

In diabetic patients, fasting hyperglycaemia is attributed to both, reduced clearance by peripheral tissues and augmented endogenous glucose release. In normal-weight, non-insulin-dependent diabetic patients, basal hepatic glucose production (HGP) was determined by means of tracer kinetic analysis. HGP was enhanced to 3.

Effect of stress hormones on splanchnic substrate and insulin disposal after glucose ingestion in healthy humans.

To compare cortisol and epinephrine action on oral glucose tolerance, healthy humans were infused with either cortisol (0.1 mg X kg-1 X h-1), epinephrine (5.4 micrograms X kg-1 X h-1), or saline before and after a 75-g glucose load, thereby elevating the respective plasma hormone concentrations into the pathophysiologic range.

Effect of hyperketonemia on renal ammonia excretion in man.

The effect of DL-sodium beta-hydroxybutyrate (Na BOHB) on urinary ammonia excretion was studied in seven chronically acidemic human subjects. Metabolic acidosis was induced by the ingestion of 0.1 g/kg body weight of ammonium chloride for three days.

Inhibition by proinsulin of endogenous C-peptide release in healthy man.

To determine the role of proinsulin on endogenous insulin release, splanchnic output and arterial concentrations of C-peptide were measured in healthy subjects before and during infusion of human (HPI) and porcine (PPI) proinsulin at increasing rates for 70 min each (HPI, 328 and 656 micrograms X m-2 X h-1; PPI, 54, 134, and 268 micrograms/m-2 X h-1), while euglycemia was maintained by variable glucose infusion. By using this approach splanchnic C-peptide output was reduced by human proinsulin infusion from 143 +/- 16 (mean +/- SE) pmol/min to 111 +/- 18 and 75 +/- 11 pmol/min (P = 0.01).

Efficacy of pulsatile versus continuous insulin administration on hepatic glucose production and glucose utilization in type I diabetic humans.

To evaluate the role of pulsatile insulin administration, hepatic glucose production (HGP) and utilization were studied in type I diabetic patients in the fasting state and during a euglycemic insulin (1 mU X kg-1 X min-1 i.v.) clamp with continuous and pulsatile insulin administration.

Failure of hyperketonemia to alter basal and insulin-mediated glucose metabolism in man.

The effect of physiologic elevations of plasma hydroxybutyrate induced by the infusion of sodium D,L-beta-hydroxybutyrate (15 mumol X kg-1 X min-1) on carbohydrate metabolism was examined with the euglycemic insulin clamp technique in nine healthy volunteers. Plasma insulin concentration was acutely raised and maintained at 126 +/- 6 microU/ml and plasma glucose was held constant at the fasting level by a variable glucose infusion. Glucose uptake of 6.

Superior efficacy of pulsatile versus continuous hormone exposure on hepatic glucose production in vitro.

To elucidate the potency of continuous vs. intermittent exposure to hormonal stimuli, hepatic glucose production of isolated perfused rat livers was monitored in response to glucagon and insulin infusion. Using a nonrecirculating perfusion system, continuous exposure to glucagon (35 pM) induced a rise in hepatic glucose production from basal 0.

Failure and efficacy of insulin therapy in insulin dependent (type I) diabetic patients.

In order to determine the degree of metabolic control (HbA1c [normal less than 5.8%], mean blood glucose [MBG], glucosuria and lipids) and the prevalence of late diabetic complications in insulin-dependent diabetic patients treated by conventional insulin therapy both patients of a diabetes center (DC: n = 130; age 37.1 +/- 1.

Acetyl-salicylic acid impairs insulin-mediated glucose utilization and reduces insulin clearance in healthy and non-insulin-dependent diabetic man.

The effect of acetyl-salicylic acid (ASA, 3 g per day for 3 days) on glucose utilization and insulin secretion was studied in healthy volunteers and Type 2 diabetic patients using the hyperglycaemic and euglycaemic insulin clamp technique. When in healthy subjects arterial plasma glucose was acutely raised and maintained at +7 mmol/l above fasting level, the plasma insulin response was enhanced by ASA (70 +/- 7 vs. 52 +/- 7 mU/l), whereas the plasma C-peptide response was identical.