Diarrhea caused by Escherichia coli that produce only heat-stable enterotoxin.

To determine the role of Escherichia coli heat-stable enterotoxin (ST) as a virulence factor in human diarrhea, a strain that elaborates only ST (E. coli 214-4) was fed to free-living volunteers in doses of 10(6), 10(8), and 10(10) organisms. Short-lived (1 day) mild illness consisting of abdominal cramps with vomiting or diarrhea occurred in three of five individuals fed 10(8). Typical travelers' diarrhea (loose stools, abdominal cramps, and low-grade fever for 2 to 3 days) was seen in four of five volunteers given 10(10); two had brief cholera-like purging of rice-water stools. Despite fever, there was no evidence of mucosal invasion. E. coli 214-4 became the predominant coliform in stools; coproculture isolates were uniformly negative for heat-labile enterotoxin (LT), whereas most produced ST. Ten of 13 individuals developed rises in antibody to somatic E. coli antigen, and none had rises in LT antitoxin. E. coli that elaborate only ST can cause diarrheal disease in adults.     

Does the perception of downloading speed influence the evaluation of web-based lectures?

Medical schools put little emphasis upon education on public health, even though public health has played an important role in this century. One way to harness its benefit in order to improve global health in the 21st century is to globally share lectures on public health through the Internet. We have developed the Supercourse comprising of web-based learning modules on epidemiology in a standardized format with the size of each web page less than 10 kilobytes. A cross-sectional observational study was conducted to investigate the association of the perception of the access speed to Web-based lectures by teachers with their perception of lecture quality. There were 223 teachers who rated the lectures: 72% were from North America or Western Europe, 40% had taught epidemiology, and 14% reported that the speed of access was slow. Odds ratio of above-average rating among those who reported that the speed of access was fast relative to those who reported that the speed of access was slow was 4.25 (2.03-8.91; P = 0.001). The odds ratios were similar and significant after taking into account several other factors, including the variation of rating across lectures, region, and experiences in teaching epidemiology. The results indicate that the perception of the quality of Web-based lectures is related to the speed of access to a web page. The speed of access may be as important, if not more important, as the content itself. This suggests that, to share educational materials on the Web globally for teachers, one must consider not only the content, but also how people at local sites gain access to the Internet.     

Stage T1 glottic carcinoma: results of radiation therapy or laser excision

A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%).