Multi-laboratory validation study of a real-time PCR method for detection of Salmonella in baby spinach.

The FDA Bacteriological Analytical Manual (BAM) Salmonella culture method takes at least 3 days for a presumptive positive result. The FDA developed a quantitative PCR (qPCR) method to detect Salmonella from 24-h preenriched cultures, using ABI 7500 PCR system. The qPCR method has been evaluated as a rapid screening method for a broad range of foods by single laboratory validation (SLV) studies.

Interlaboratory Validation for a Real-Time PCR Salmonella Detection Method Using the ABI 7500 FAST Real-Time PCR System.

Sixteen FERN (Food Emergency Response Network) member laboratories collaborated in this study to verify extension of the real-time PCR Salmonella detection method originally designed for the single-tube Cepheid SmartCycler II and validated against the Salmonella method of the U. S. Food and Drug Administration Bacteriological Analytical Manual to the Applied Biosystems (ABI) 7500 FAST Real-Time PCR system multiwell plate platform.

Detection and Identification of Salmonella enterica, Escherichia coli, and Shigella spp. via PCR-electrospray ionization mass spectrometry: isolate testing and analysis of food samples.

An assay to identify the common food-borne pathogens Salmonella, Escherichia coli, Shigella, and Listeria monocytogenes was developed in collaboration with Ibis Biosciences (a division of Abbott Molecular) for the Plex-ID biosensor system, a platform that uses electrospray ionization mass spectroscopy (ESI-MS) to detect the base composition of short PCR amplicons. The new food-borne pathogen (FBP) plate has been experimentally designed using four gene segments for a total of eight amplicon targets. Initial work built a DNA base count database that contains more than 140 Salmonella enterica, 139 E.

The evaluation of a PCR-based method for identification of Salmonella enterica serotypes from environmental samples and various food matrices.

The most commonly used method for serotyping Salmonella spp. is based on the Kaufmann-White scheme, and is composed of serological reactions using antibodies to LPS agglutinins. The multiplex PCR used in this investigation was established by Kim et al.

A target-selected Apc-mutant rat kindred enhances the modeling of familial human colon cancer.

Progress toward the understanding and management of human colon cancer can be significantly advanced if appropriate experimental platforms become available. We have investigated whether a rat model carrying a knockout allele in the gatekeeper gene Adenomatous polyposis coli (Apc) recapitulates familial colon cancer of the human more closely than existing murine models. We have established a mutagen-induced nonsense allele of the rat Apc gene on an inbred F344/NTac (F344) genetic background.

Perillyl alcohol inhibits a calcium-dependent constitutive nuclear factor-kappaB pathway.

The cell death induced by the monoterpene anticancer agent perillyl alcohol correlates to the increased expression of certain proapoptotic genes known to influence cell survival. Whereas sequence-specific DNA-binding factors dictate the expression patterns of genes through transcriptional regulation, those transcriptional factors influencing constitutive cell survival with perillyl alcohol treatment are not well studied. Here, we investigated whether the monoterpenes can regulate the activity of nuclear factor-kappaB (NF-kappaB), a calcium-dependent transcription factor necessary for survival in the WEHI-231 B-lymphoma cells.

Development of a universal gap repair vector for yeast-based screening of knockout rodents.

Recently, we reported the production of the first knockout rats by combining N-ethyl-N-nitrosourea (ENU)-induced mutagenesis with a yeast-based truncation screening method. To make this new knockout technology more applicable for other laboratories and for high-throughput applications, we have developed a universal gap repair vector that is ready for use in screening for gene knockouts without additional engineering. The universal gap repair vector was validated for its application in both cDNA- and genomic DNA-based yeast truncation mutation assays.

Production of knockout rats using ENU mutagenesis and a yeast-based screening assay.

The rat is a widely used model in biomedical research and is often the preferred rodent model in many areas of physiological and pathobiological research. Although many genetic tools are available for the rat, methods to produce gene-disrupted knockout rats are greatly needed. In this study, we developed protocols for creating N-ethyl-N-nitrosourea (ENU)-induced germline mutations in several rat strains.

Androgen-dependent mammary carcinogenesis in rats transgenic for the Neu proto-oncogene.

Transgenic rats were created with overexpression of the Neu proto-oncogene in the mammary gland of both sexes, yet only males developed mammary cancer in an androgen-dependent fashion. Transgenic females only developed mammary cancer if treated with androgens. These tumors were positive for androgen receptor (AR), but negative for estrogen and progesterone receptors.