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Proteus mirabilis is an important pathogen involved in human urinary tract infections, and also more isolated from stools of patients with diarrheal disease than from healthy patients. The role of food, especially poultry products as source for human infection and multi-resistant strains remains unclear. As a resident in broilers' intestines, P. mirabilis can contaminate broiler carcasses due to slaughter practices, and be a risk for human infection. The present study evaluated the performance of five isolation media, and subsequently examined the presence of P. mirabilis on broiler carcasses at retail. Additionally, isolates were characterized by the Dienes' test, repetitive element PCR fingerprinting and pulsed-field gel electrophoresis, and their antibiotic resistance profile determined. Using a combined isolation protocol on blood agar, xylose lysine deoxycholate agar and violet red bile glucose agar, P. mirabilis was isolated from 29 out of 80 broiler carcasses (36.25%) with a mean contamination level of 2.25 ± 0.50 log 10  CFU/g. A high strain heterogeneity was present in isolates from broilers and human stool. The same strains were not shared, but the antibiotic resistance profiling was similar. A role of poultry products as source for human infection should be taken into account., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Chronic kidney disease (CKD) is characterized by accumulation of protein-bound uremic toxins such as p-cresyl sulfate, p-cresyl glucuronide, indoxyl sulfate and indole-3-acetic acid, which originate in the gut. Intestinal bacteria metabolize aromatic amino acids into p-cresol and indole, (further conjugated in the colon mucosa and liver) and indole-3-acetic acid. Here we measured fecal, plasma and urine metabolite concentrations; the contribution of gut bacterial generation to plasma protein-bound uremic toxins accumulation; and influx into the gut of circulating protein-bound uremic toxins at different stages of CKD. Feces, blood and urine were collected from 14 control individuals and 141 patients with CKD. Solutes were quantified by ultra-high performance liquid chromatography. To assess the rate of bacterial generation of p-cresol, indole and indole-3-acetic acid, fecal samples were cultured ex vivo. With CKD progression, an increase in protein-bound uremic toxins levels was observed in plasma, whereas the levels of these toxins and their precursors remained the same in feces and urine. Anaerobic culture of fecal samples showed no difference in ex vivo p-cresol, indole and indole-3-acetic acid generation. Therefore, differences in plasma protein-bound uremic toxins levels between different CKD stages cannot be explained by differences in bacterial generation rates in the gut, suggesting retention due to impaired kidney function as the main contributor to their increased plasma levels. Thus, as fractional clearance decreased with the progression of CKD, tubular clearance appeared to be more affected than the glomerular filtration rate, and there was no net increase in protein-bound uremic toxins influx into the gut lumen with increased plasma levels., (Copyright © 2020 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Examination of the bacterial contamination on food products is still largely performed by standardized culture methods, though culture-independent methods are suggested as a more reliable approach. Knowledge of the diversity of bacteria isolated from food as well as the impact of the plate incubation conditions applied are still understudied. The impact of incubation at 7 °C and 30 °C on total aerobic bacterial count and diversity, and the performance of ISO methods generally applied in microbiological quality examination were assessed by culture combined MALDI-TOF MS identification and 16S rRNA amplicon sequencing. Examining breast skin of 16 chicken carcasses, no significant impact of the incubation temperature on the total aerobic bacteria level and diversity was detected, limiting the usefulness of additional psychrophilic examination. Bacteria phenotypically similar to Pseudomonas, were identified on selective CFC plates, and on MRS agar plates for lactic acid bacteria, Escherichia coli and Staphylococcus were commonly present. Application of 16S rRNA amplicon sequencing revealed a higher bacterial diversity, but the impact of the DNA extraction kit applied, and the detection of non-viable bacteria should be taken into account to interpret the final outcome., (Copyright © 2019. Published by Elsevier Ltd.)