ALCOHOL DECREASES INSULIN SENSITIVITY IN HEALTHY SUBJECTS

To study the effect of alcohol on glucose and insulin metabolism,a simultaneous infusion of glucose and insulin was given for150 min to healthy volunteers, once during alcohol and onceduring calorie-free gingerale (control) ingestion. During alcoholintake, the average steady-state (between 100 and 150 min) glucoseof 5.44±0.39 mmol/1. and the average steady-state insulinof 6.3±1.1 ng/ml were significantly higher than those(4.0±0.39 mmol/1. of glucose and 4.4±0.6 ng/mlof insulin) observed during the control state. Despite the highersteady-state insulin concentrations, the glucose metabolismwas significantly less during alcohol ingestion. These findingssuggest alcohol-induced impairment in glucose metabolism iscaused by a decreased tissue sensitivity to insulin.     

Unraveling the mysteries of serum theophylline levels: a patient care report in the light of pharmacokinetics

One of our patients had trouble maintaining therapeutic and safe levels of theophylline, even though we were careful in planning and monitoring her drug regimen. This case report shows how we were able to use principles of pharmacokinetics to distinguish among plausible explanations for her experience. We discovered that she was not taking the drug consistently as prescribed and that supervised administration resolved apparent contradictions between doses and serum levels. We believe that physicians can use the same information and methods that we used to get better and safer results from theophylline therapy.     

Accessory left-ventricular chorda and the early ventricular repolarization syndrome

Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05).     

Stimulus-secretion coupling of arginine-induced insulin release. Resistance of arginine- and ornithine-stimulated glucagon and insulin release to D,L-alpha-difluoromethylornithine

In the isolated perfused rat pancreas, D,L-difluoromethylornithine, tested at a concentration of 3 mmol/L, failed to affect the release of glucagon and insulin caused, over 15 min stimulation, by either L-arginine or L-ornithine (2.0, 5.0 or 10.0 mmol/L) in the presence of either 3.3 or 5.6 mmol/L D-glucose. The inhibition of ornithine decarboxylase also failed to affect the release of glucagon provoked by either L-leucine (2 or 3 mmol/L) or L-glutamine (2 mmol/L) and the secretion of insulin stimulated by a rise in glucose concentration from 5.6 to 10.6 mmol/L. These data are interpreted to suggest that the rapid generation of polyamines from either L-arginine or L-ornithine does not play any significant role in the immediate glucagonotropic and insulinotropic action of these cationic amino acids.