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Background: The involvement of non-human-to-human transmission of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) remains elusive. Foodstuffs may serve as reservoirs for ESBL-PE and contribute to their spread. Aim: We aimed to systematically investigate the presence and spatiotemporal distribution of ESBL-PE in diverse unprocessed foodstuffs of different origin purchased in a central European city. Methods: Chicken and green (herbs, salad, sprouts, vegetables) samples were collected monthly for two consecutive years, from June 2017 to June 2019, from large supermarket chains and small local food retailers, representing all ten postcode areas of the City of Basel (Switzerland), and the kitchen of the University Hospital Basel (Basel, Switzerland). After enrichment, presumptive ESBL-PE were isolated by selective culture methods and identified by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. ESBL production was confirmed by phenotypic testing. Results: Among 947 food samples, 14.8% were positive for ESBL-PE isolate/s belonging to eight different ESBL-producing bacterial species. Escherichia coli and Serratia fonticola were predominant across samples (9 and 2%, respectively). Higher ESBL-PE prevalence was observed in chicken (25.9%) than in green (3.8%) samples (p  <  0.001). Among greens, ESBL-PE were most frequently isolated from sprouts (15.2%). High ESBL-PE species diversity was observed among chicken samples, with E. coli as predominant (17.6%). ESBL-producing Enterobacter cloacae was detected among different greens. Yet, ESBL-producing Klebsiella pneumoniae was predominant in sprouts (12.1%). In total, 20.5% of samples from organic farming and 14.2% of samples from conventionally raised animals harbored an ESBL-producing isolate. Detection of ESBL-PE across samples differed between organic and non-organic when stratified by food source (p  <  0.001), particularly among greens (12.5% organic, 2.4% conventional). High proportion of organic chicken samples was positive for ESBL-E. coli (33.3%), while the detection of several species characterized the conventional chicken samples. No significant differences in ESBL-PE frequences were detected between national (13.4%) and international samples (8.0%) (p  =  0.122). Instead, differences were observed between regions of food production and countries (p  <  0.001). No significant differences were found when comparing the proportion of ESBL-PE positive samples across districts, shop sizes and the hospital kitchen. The percentage of ESBL-PE positive samples did not differ monthly across the two-year sampling period (p  =  0.107). Conclusion: Our findings indicate moderate dissemination of ESBL-PE in foodstuffs, especially between chicken products and sprouts. Chicken meat represents a source for several ESBL-producing Enterobacterales, especially E. coli, while greens are more prone to carry ESBL-K. pneumoniae and E. cloacae. We disclose the importance of food type, food production system and production origin when assessing the risk of contamination with different ESBLPE species. [ABSTRACT FROM AUTHOR]

We report a cluster of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae sequence type 101, derived from 1 poultry and 2 clinical samples collected within the setting of a prospective study designed to determine the diversity and migration of ESBL-producing Enterobacterales between humans, foodstuffs, and wastewater. [ABSTRACT FROM AUTHOR]

Embryonal stem (ES) cells that are homozygous null for the [[Beta].sub.1] integrin subunit fail to differentiate into keratinocytes in vitro but do differentiate in teratomas and wild-type/[[Beta].sub.1]-null chimeric mice. The failure of [[Beta].sub.1]-null ES cells to differentiate in culture might be the result of defective extracellular matrix assembly or reduced sensitivity to soluble inducing factors. By culturing embryoid bodies on dead, deepidermized human dermis (DED) we showed that epidermal basement membrane did not induce [[Beta].sub.1]-null ES cells to undergo keratinocyte differentiation and did not stimulate the differentiation of wild-type ES cells. Coculture with epidermal keratinocytes also had no effect. However, when human dermal fibroblasts were incorporated into DED, the number of epidermal cysts formed by wild-type ES cells increased dramatically, and small groups of keratin 14-positive cells differentiated from [[Beta].sub.1]-null ES cells. Fibroblast-conditioned medium stimulated differentiation of K14-positive cells in wild-type and [[Beta].sub.1]-null embryoid bodies. Of a range of growth factors tested, KGF, FGF10, and TGF[Alpha] all stimulated differentiation of keratin 14-positive [[Beta].sub.1]-null cells, and KGF and FGF10 were shown to be produced by the fibroblasts used in cocuhure experiments. The effects of the growth factors on wild-type ES cells were much less pronounced, suggesting that the concentrations of inducing factors already present in the medium were not limiting for wild-type cells. We conclude that the lack of [[Beta].sub.1] integrins decreases the sensitivity of ES cells to soluble factors that induce keratinocyte differentiation. [C] 2001 Academic Press Key Words: ES cells; integrins; keratinocytes; basement membrane; fibroblast growth factors; TGF[Alpha]; TGF[Beta]

Investigates whether gene regulation by the mammalian opa homologue zic-1 was influenced by the intracellular domain of teneurin-2, a vertebrate homologue of the Drosophila pair-rule gene ten-m/odz. Inhibition of zic-mediated transcription from the apoliprotein E promoter; Stimulation of the release of the intracellular domain of teneurin-2 by homophilic interaction of the extracellular domain; Promyelocytic leukemia.