Data Sharing, Clinical Trials, and Biomarkers in Precision Oncology: Challenges, Opportunities, and Programs at the Department of Veterans Affairs.

Cancer genomic research reveals that a similar cancer clinical phenotype (e.g., non-small cell lung cancer) can arise from various mutations in tumor DNA. Thus, organ of origin is not a definitive classification. Further, targeted therapy for cancer patients (precision oncology) capitalizes on knowledge of individual patient mutational status to deliver treatment directed against the protein products of these mutations with the goal of reducing toxicity and enhancing efficacy relative to traditional nontargeted chemotherapy.

Fate of pGFP-bearing Escherichia coli O157:H7 in ground beef at 2 and 10 degrees C and effects of lactate, diacetate, and citrate.

Although beef has been implicated in the largest outbreaks of Escherichia coli O157:H7 infection in the United States, studies on the fate of this pathogen have been limited. Problems in such studies are associated with detection of the pathogen at levels considerably lower than the levels of the competing microorganisms. In the present study, a green fluorescent protein-expressing E. coli O157:H7 strain was used, and the stable marker allowed us to monitor the behavior of the pathogen in ground beef stored aerobically from freshness to spoilage at 2 and 10 degrees C. In addition, the effects of sodium salts of lactate (SL) (0.9 and 1.8%), diacetate (SDA) (0.1 and 0.2%), and buffered citrate (SC) (1 and 2%) and combinations of SL and SDA were evaluated. SC had negligible antimicrobial activity, and SL delayed microbial growth, while SDA and SL plus SDA were most inhibitory to the total-aerobe population in the meat. At 2 degrees C, the initial numbers of E. coli O157:H7 (3 and 5 log(10) CFU/g) decreased by approximately 1 log(10) CFU/g when spoilage was manifest (>7 log(10) CFU of total aerobes/g), irrespective of the treatment. There was no decline in the numbers of the pathogen during storage at 10 degrees C. Our results showed that the pathogen was resistant to the salts tested and confirmed that refrigerated meat contaminated with the pathogen remains hazardous.