Leanne H Field

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Three human isolates of Campylobacter jejuni were grown in a biphasic culture medium with and without the addition of a synthetic chelator to induce iron limitation. Cells grown in low-iron medium exhibited slower growth rates and altered cellular morphology. Increased numbers of longer, more filamentous forms were seen in Gram-stained smears. Three(More)
Eleven-day-old chicken embryos were used to compare the relative virulence of minimally passaged human isolates of Campylobacter jejuni and Campylobacter coli. Graded doses of bacteria were inoculated onto the chorioallantoic membrane, and 50% lethal doses were calculated at 72 h postinfection. Strains varied markedly in their ability to invade the(More)
Infant mice have been shown previously to be a useful model for the study of gastrointestinal (GI) and systemic candidosis. In this study, the virulence of four strains of Candida albicans was compared in intragastrically inoculated infants and in adult mice inoculated intravenously. The four strains differed in their ability to kill both infant and adult(More)
Children under the age of 5 years experience a disproportionately high rate of bacterial enteric infections. Research has shown a relationship between inadequate child-care center sanitation and illnesses in children. This cross-sectional study assessed the sanitation levels of foodservice surfaces in a sample of 36 Texas child-care centers via recovery and(More)
Neonatal mice (2.3 to 2.8 g) were inoculated intragastrically with different human isolates of Campylobacter fetus subsp. jejuni. At weekly intervals thereafter, mice were sacrificed and dilution plate counts were performed on segments of the gastrointestinal tract. Mice were uniformly colonized by some strains for 2 weeks, whereas other strains were being(More)
The 11-day-old chicken embryo has been shown to be a useful animal model for comparing the virulence of human isolates of Campylobacter jejuni. Virulence in this system is associated with the ability to invade the chorioallantoic membrane and to survive and proliferate in vivo. In this study, the survival and multiplication of C. jejuni in the embryonic(More)
A tube dilution test to evaluate the effectiveness of antibiotics against Bordetella pertussis is described. Five B. pertussis strains, including a well-characterized research strain and four fresh clinical isolates, were tested with several antibiotics. Erythromycin showed the highest in-vitro activity of the antibiotics tested. A concentration of 0.12(More)
We examined jail environmental surfaces to explore whether they might serve as reservoirs of viable methicillin-resistant Staphylococcus aureus (MRSA). We swabbed 132 surfaces, inoculated primary and secondary mannitol salts and oxacillin-resistant screening agar, and used API tests to identify S. aureus and E-tests to determine methicillin/oxacillin(More)
Infant mice 8 days of age were infected orally with virulent, motile, classical or El Tor strains of Vibrio cholerae and with nonmotile mutants of low virulence derived from the same strains. At intervals of 8 and 12 h postinfection, frozen thin sections of the ileum were prepared, stained with fluorescein isothiocyanate-labeled rabbit anti-vibrio antibody,(More)
Differential centrifugation was used to prepare fractions from broken cells of Bordetella pertussis strain 114. Whole cells and several fractions were then assayed for potency and for safety. Crude ribosomal fractions were uniformly protective. However, ribosomes purified by washing in high salt solution and recentrifugation were at least 40 fold less(More)