Fate of Escherichia coli O145 present naturally in bovine slurry applied to vegetables before harvest, after washing and simulated wholesale and retail distribution

Aims: To determine the fate of E. coli on vegetables that were processed through commercial wash treatments and stored under simulated retail conditions at 4oC or wholesale at fluctuating ambient temperatures (0-25oC, dependent on season). Methods and Results: Bovine slurry that was naturally contaminated with Escherichia coli O145 was applied without dilution or diluted 1/10 using borehole water to growing potatoes, leeks or carrots. Manure was applied one week prior to harvest to simulate a near-harvest contamination event by manure deposition or an application of contaminated water to simulate a flooding event or irrigation from a contaminated water source. At harvest, crops were contaminated at up to two log cfu/g. Washing transferred E. coli into the water of a flotation tank used for potato washing and did not completely remove all traces of contamination from the crop. Manure contaminated potatoes were observed to contain 0.72 cfu E. coli O145/g after processing and retail storage. Manure-contaminated leeks harboured 0.73 – 1.55 cfu E. coli O145/g after washing and storage. There was no cross contamination when leeks were spray-washed. Washing in an abrasive drum resulted in less than perfect decontamination for manure-contaminated carrots. There were five post-distribution isolations from carrots irrigated with contaminated water 24h prior to harvest. Conclusions: Standard commercial washing and distribution conditions may be insufficient to reliably control human pathogenic E. coli on fresh produce. Significance and Impact: Previous speculation that the cause of a UK foodborne disease outbreak was soil from imperfectly cleaned vegetables is plausible

Histone H3.3 beyond cancer: Germline mutations in Histone 3 Family 3A and 3B cause a previously unidentified neurodegenerative disorder in 46 patients

Although somatic mutations in Histone 3.3 (H3.3) are well-studied drivers of oncogenesis, the role of germline mutations remains unreported. We analyze 46 patients bearing de novo germline mutations in histone 3 family 3A (H3F3A) or H3F3B with progressive neurologic dysfunction and congenital anomalies without malignancies. Molecular modeling of all 37 variants demonstrated clear disruptions in interactions with DNA, other histones, and histone chaperone proteins. Patient histone posttranslational modifications (PTMs) analysis revealed notably aberrant local PTM patterns distinct from the somatic lysine mutations that cause global PTM dysregulation. RNA sequencing on patient cells demonstrated up-regulated gene expression related to mitosis and cell division, and cellular assays confirmed an increased proliferative capacity. A zebrafish model showed craniofacial anomalies and a defect in Foxd3-derived glia. These data suggest that the mechanism of germline mutations are distinct from cancer-associated somatic histone mutations but may converge on control of cell proliferation

Monitoring of the intra-dermal tuberculosis skin test performed by Belgian field practitioners

The present study aimed to monitor skin test practices as performed by veterinarian field practitioners in Belgium. For this purpose, an anonymous postal questionnaire was elaborated and dispatched to veterinarians involved in bovine tuberculosis detection. The questionnaire included items focusing on the skin test performance. International experts in the field of bovine tuberculosis were asked to fill the questionnaire and a scoring scale was built as follows: 0='ideal' answer, 1=acceptable answer, whereas 2=unacceptable answer. Furthermore, experts were asked to rank the questionnaire's items according to their possible impact on the risk of not detecting reactors. A global score was further calculated for each participant and a comparison of practices was carried out between the two regions of the country, i.e. Wallonia and Flanders. Significant differences were observed between both regions, a harmonization at the country level is thus essential. No veterinarian summed a null score, corresponding to the ideal skin test procedure, which suggests that skin-testing is far from being performed correctly. Field practitioners need to be sensitized to the importance of correctly performing the test. The authors recommend the questionnaire is suitable for application in other countries or region