The G.U.T. of gut

Fiorucci S, Distrutti E, Bassotti G, Gerli R, Chiucchiù S, Betti C, Santucci L, Morelli A. Effect of erythromycin administration on upper gastrointestinal motility in scleroderma patients. Scand J Gastroenterol 1994;29:807-813.

Background: Gastrointestinal involvement is frequent in patients with scleroderma. Erythromycin, a macrolide antibiotic, has been shown to accelerate gastric emptying in normal subjects and diabetic patients. The present study investigated the effects of acute erythromycin administration on gastric and gallbladder motility in patients with scleroderma and gastrointestinal involvement. Methods: Twelve scleroderma patients and 14 healthy subjects were investigated. Each subject was investigated on 4 different days. Gastric and gallbladder emptying and gastric motility were determined by sonography and manometry, and the effect of 2 mg/kg/h erythromycin in fasted patients or after semisolid meal evaluated. Results: The half-time of gastric emptying in response to semisolid meal was 121.3 ± 14.0 min (SE) in scleroderma patients and 45.7 ± 10.4 min in healthy subjects (P < 0.01). The peak of gallbladder emptying occurred later in scleroderma patients (95.0 ± 5.0 min) than in healthy subjects (45.0 ± 8.0 min) (P < 0.01). Erythromycin stimulated gastric and gallbladder motility in fasted subjects, as shown by manometry and sonography, and accelerated gastric and gallbladder emptying when administered immediately before the meal (P < 0.01). Conclusions: Erythromycin accelerates gastric and gallbladder emptying in scleroderma patients and might be helpful in the treatment of gastrointestinal motor abnormalities in these patients.     

Endocrine responses of ovariectomized ewes to i.c.v. infusion of urocortin.

Urocortin is a novel corticotropin-releasing factor-like peptide, first isolated from the rat midbrain, which has anorexigenic properties, possibly associated with its involvement in the stress axis. Urocortin has been implicated in blood pressure regulation, ACTH release and feed intake, but its role as an integral component of the reproduction-nutrition axis has not been examined. The present experiment was designed to determine the effects of i.c.v. infusion of urocortin on feed intake and endocrine profiles of LH, GH, IGF-I, cortisol and leptin in ovariectomized ewes. Ewes were fitted with two laterocerebroventricular cannulae and urocortin was continuously infused in a linearly increasing manner from 0.001 microg/h on day 0, to a maximum of 31.6 microg/h on day 5. Blood samples were collected via jugular catheters at 10 min intervals for 4 h on day 1, 3 and 5, and assayed by RIA for LH, GH, IGF-I, cortisol and leptin. All ewes were allowed free access to feed and water, and feed intake was recorded daily. Urocortin-infused ewes responded with a significant decrease in feed intake beginning on day 1 (P<0.02) and were aphagic for the remainder of the experiment. Serum concentrations of LH were elevated in individual samples from urocortin-treated compared with saline-treated ewes on day 3 (treatment x day x sample, P=0.05), but were not different on day 1 or 5. Mean serum concentrations of GH increased (P<0.04) over days with urocortin treatment, although concentrations of IGF-I were not influenced by treatment (P>0.5). Serum concentrations of cortisol were markedly increased by urocortin treatment (P<0.001). Leptin tended to be influenced by treatment and day (P=0.08), with leptin levels tending to be elevated in urocortin-treated vs saline-treated ewes on day 5 (P=0.08). The ability of urocortin to decrease feed intake while increasing LH, GH, cortisol and leptin provides evidence that urocortin is not only an integral component of the stress axis, but possibly of the nutrition-reproduction axis in sheep.     

Types of clinical studies. I. Case-control studies.

In an age when there is a general belief that clinical practice should be based on the best scientific evidence available, its selection and critical appraisal is crucial. The first step should therefore be to define the existing types of studies, and analyze their objectives, advantages and disadvantages, use and synthesis. In this, the first of a series of articles defining types of clinical studies, we present case-control studies. This type of study is a valid research methodology, producing important data with less time, cost and effort than other types of research studies. Its implementation, however, is complicated by the fact that case-control studies are more susceptible to bias. Attention to specific details--selection criteria for cases and controls, origin of the controls, blinding of data collectors and standardization of their procedures, and management of confounding factors--will improve the quality of the results obtained in case-control studies.     

Types of clinical studies. IV. Clinical trials.

Clinical practice should be based on the best available information from high-quality studies. Among the various study models, the randomized controlled trial, despite some disadvantages, is usually considered the gold standard for determining the efficacy of an intervention (drugs, surgery, etc.), and so this type of study should be part of all rational, conscious clinical decision-making. In this article, we present the classic structure of a randomized controlled trial, together with indications for critical appraisal of quality, as well as a brief discussion of the design, conduct and results, for correct determination of an intervention's effect.