Salmonella Detection in Food Using a HEK-hTLR5 Reporter Cell-Based Sensor.

The development of a rapid, sensitive, specific method for detecting foodborne pathogens is paramount for supplying safe food to enhance public health safety. Despite the significant improvement in pathogen detection methods, key issues are still associated with rapid methods, such as distinguishing living cells from dead, the pathogenic potential or health risk of the analyte at the time of consumption, the detection limit, and the sample-to-result. Mammalian cell-based assays analyze pathogens' interaction with host cells and are responsive only to live pathogens or active toxins. In this study, a human embryonic kidney (HEK293) cell line expressing Toll-Like Receptor 5 (TLR-5) and chromogenic reporter system (HEK dual hTLR5) was used for the detection of viable Salmonella in a 96-well tissue culture plate. This cell line responds to low concentrations of TLR5 agonist flagellin. Stimulation of TLR5 ligand activates nuclear factor-kB (NF-κB)-linked alkaline phosphatase (AP-1) signaling cascade inducing the production of secreted embryonic alkaline phosphatase (SEAP). With the addition of a ρ-nitrophenyl phosphate as a substrate, a colored end product representing a positive signal is quantified. The assay's specificity was validated with the top 20 Salmonella enterica serovars and 19 non-Salmonella spp. The performance of the assay was also validated with spiked food samples. The total detection time (sample-to-result), including shortened pre-enrichment (4 h) and selective enrichment (4 h) steps with artificially inoculated outbreak-implicated food samples (chicken, peanut kernel, peanut butter, black pepper, mayonnaise, and peach), was 15 h when inoculated at 1-100 CFU/25 g sample. These results show the potential of HEK-DualTM hTLR5 cell-based functional biosensors for the rapid screening of Salmonella.

Transforming training into practice with the conflict management framework: a mixed methods study.

Objective: To implement and evaluate the use of the conflict management framework (CMF) in four tertiary UK paediatric services. Design: Mixed methods multisite evaluation including prospective pre and post intervention collection of conflict data alongside semistructured interviews. Setting: Eight inpatient or day care wards across four tertiary UK paediatric services. Interventions: The two-stage CMF was used in daily huddles to prompt the recognition and management of conflict. Results: Conflicts were recorded for a total of 67 weeks before and 141 weeks after implementation of the CMF across the four sites. 1000 episodes of conflict involving 324 patients/families across the four sites were recorded. After implementation of the CMF, time spent managing episodes of conflict around the care of a patient was decreased by 24% (p<0.001) (from 73 min to 55 min) and the estimated cost of this staff time decreased by 20% (p<0.02) (from £26 to £21 sterling per episode of conflict). This reduction occurred despite conflict episodes after implementation of the CMF having similar severity to those before implementation. Semistructured interviews highlighted the importance of broad multidisciplinary leadership and training to embed a culture of proactive and collaborative conflict management. Conclusions: The CMF offers an effective adjunct to conflict management training, reducing time spent managing conflict and the associated staff costs.