A prospective, randomized controlled study of computer-assisted learning in parasitology.

PURPOSE: To compare, using a prospective, randomized controlled study, three methods of teaching a medical school parasitology course: computer-based instruction, traditional lecture-based instruction, and a combination of computer-based and lecture-based instruction. METHOD: A single class of the University of Utah School of Medicine was randomized into three study groups for the second-year parasitology course. The computer group (n = 29) used a locally developed interactive parasitology computer program; the lecture group (n = 32) had traditional lectures, and the combined group (n = 33) used both the computer program and lectures. Students' knowledge was assessed using a pretest, a final examination, and a posttest administered four months after the course. Students also used logs to track the amounts of time they spent studying. Their impressions and course evaluations were collected using a standardized course-evaluation form. RESULTS: The groups' scores on the pretest, final examination, and posttest were not statistically significantly different. Students in the computer group averaged 26.8 hours of studying over the two-week course compared with 32.1 hours in the lecture group and 32.7 hours in the combined group. The difference in study times between the computer and combined groups yielded a significant p value of 0.036. Students were generally positive about the course and the computer program. CONCLUSION: Students can learn parasitology from computer-based instruction as effectively as from traditional lecture-based instruction, and they can do so in less time.     

Intimal hyperplasia and coronary flow reserve after heart transplantation: association with big endothelin-1

BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.