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F S Newman

Publications and source records attributed to F S Newman.

12 recordsLinked to original sources

Geographic and specialty distributions of WAMI Program participants and nonparticipants.

In an effort to make the geographic distribution of physicians closer to the distribution of the population as a whole, in 1971 the states of Washington, Alaska, Montana, and Idaho established the WAMI Program. In a departure from the Flexnerian model of medical education, the WAMI Program was organized to distribute the components of medical education throughout the region, both at the medical center at the University of Washington School of Medicine and at remote sites. In the present article, the authors describe the results of the first seven years of the program (1975-1981) in terms of the geographic and specialty distribution of the school's graduates before and after the establishment of the program. At the time of the study, 23 percent of the graduates with WAMI Program experience practiced in nonmetropolitan areas as defined by the U.S. Bureau of the Census. Only 13 percent of all U.S. physicians practiced in such areas in 1981, while 24 percent of the U.S. population lived there. In addition, 61 percent of the graduates with program experience were in primary care practice in contrast to 35 percent of all U.S. physicians. If all U.S. physicians behaved as these graduates do, the distribution of U.S. physicians would be reversed, with the proportion of physicians practicing primary care in nonmetropolitan areas being larger than the proportion of the population living in those areas.

Alaska↗

Isolation of enterotoxigenic Bacteroides fragilis from humans with diarrhea.

Enterotoxigenic Bacteroides fragilis was isolated from stool specimens of 8 of 44 diarrheic individuals (ages, 4 months to 69 years). The individuals had watery diarrhea and intestinal cramping; and infants had hyperthermia, vomiting, and blood in the stools. No recognized enteric pathogens were detected in seven of the eight diarrheic individuals positive for enterotoxigenic B. fragilis. The bacterium produced an enterotoxin detectable in concentrated broth that supported bacterial growth. Fifteen adult rabbits with ligated ceca developed fatal enteric disease following intraileal injection with 5 x 10(9) CFU of enterotoxigenic B. fragilis. Conversely, eight control rabbits injected with nonenterotoxigenic B. fragilis remained clinically normal. As few as 5 x 10(3) CFU of enterotoxigenic B. fragilis caused fatal enteric disease in the rabbit model. Disease in rabbits was characterized by mucoid, often hemorrhagic, diarrhea. The bacterium colonized the caudal small intestine and the colon of the rabbits and caused moderate to severe necrotizing colitis. Enterotoxigenic B. fragilis is widespread in the intestinal tract of diarrheic humans and is enteropathogenic in adult rabbits with ligated ceca. Its possible role in the enteric disease complex merits further study.

Adult↗

Classification of Vibrio bacteriophages.

85 Vibrio phages, 84 of them tailed and 1 filamentous, were surveyed. The tailed phages belonged to six basic morphotypes and to the Myoviridae, Siphoviridae, or Podoviridae families. 63 phages were classified into 18 species. The filamentous phage is a member of the Inovirus genus of the Inoviridae family. Vibrio phages are very heterogenous and include some morphologically interesting viruses. Several Vibrio phages closely resemble phages of other gram-negative bacteria, possibly indicating phylogenetic relationships between their hosts.

Bacteriophages↗

Calf ligated intestinal segment test to detect enterotoxigenic Escherichia coli.

The ligated intestinal segment test in the young calf was utilized to establish the enterotoxigenicity of approximately 600 Escherichia coli isolates obtained from fecal specimens intestinal contents of calves with diarrheal disease. One hundred and fifty isolates were routinely tested in a single calf. There was little problem with false-positive reactions. False-negative reactions normally occurred only if the isolate was tested in the posterior 3 m of the small intestine. The ligated small intestine of the calf was distended by E. coli isolates of bovine, porcine, and human origin. Use of the calf ligated intestinal segment test is recommended to determine the enterotoxigenicity of E. coli isolates of bovine origin.

Animals↗

Prevention of experimentally induced enteric colibacillosis in newborn calves.

Severe enteric colibacillosis, characterized by profuse watery diarrhea, dehydration, apathy, hypothermia, and inability to stand, was produced in seven of eight newborn, colostrum-fed calves from nonvaccinated dams after oral challenge of calves with 10(11) viable cells of Escherichia coli strain B44. Twenty-nine of 32 calves from dams vaccinated with various preparations of E. coli strain B44 were protected against severe enteric colibacillosis after oral challenge. Calves were protected if the dams received two subcutaneous vaccinations prior to calving. Calves also were protected if the dams were given a homologous vaccine of live or killed whole cells or a broth culture supernatant vaccine via the subcutaneous and intramammary routes 1 year earlier. Nineteen of the 29 protected calves had a transient diarrhea.

Animals↗