Publications by authors named "P A Horgen"

The purpose of this study was to apply our rapid, integrated double enrichment 5' nuclease real-time polymerase chain reaction assay for the detection of Escherichia coli O157:H7 and evaluate its efficacy. The assay targeted ground beef, an important vehicle in disease epidemiology. The assay reliably determined in 8 h the presence of E.

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A rapid test for microbial quantification in carcass and environmental swabs that does not require enrichment and provides results in less than 4 h is described here. Steps in the assay include the rapid concentration of bacteria on sponge swabs by vacuum filtration followed by real-time PCR detection. The assay has been applied for the detection of coliforms, Escherichia coli O157:H7, Salmonella spp.

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We evaluated the influence of mitochondrial haplotype on growth of the common button mushroom Agaricus bisporus. Ten pairs of heterokaryon strains, each pair having the same nuclear genome but different mitochondrial genomes, were produced by controlled crosses among a group of homokaryons of both wild and commercial origins. Seven genetically distinct mitochondrial DNA (mtDNA) haplotypes were evaluated in different nuclear backgrounds.

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Real-time PCR, using dual-labeled fluorescent probes targeting the beta-giardin gene, was used to detect Giardia lamblia in human stool specimens and to discriminate between isolates from the two major genetic assemblages of G. lamblia infective to humans, assemblages A and B.

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Cerato-ulmin is a surface protein that belongs to the class of fungal proteins known as hydrophobins. This class II hydrophobin is produced throughout the life cycle and in all developmental stages of Ophiostoma novo-ulmi and O. ulmi; the aggressive and non-aggressive pathogens responsible for Dutch elm disease.

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