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To our knowledge, this is the largest admission prevalence study of 3GCREB in Europe. The observed prevalence of 9.5% 3GCREB carriage was higher than previously reported and differed significantly among centres. In addition to previously identified risk factors, the treatment of GERD proved to be an independent risk factor for 3GCREB colonization.

Beginning with their discovery in the context of stem cell fate choice in Caenorhabditis elegans, the microRNA (miRNA) let-7 and the RNA-binding protein Lin28 have been recognized as a regulatory pair with far-reaching impact on stem cell behavior in a wide range of organisms and tissues, including the mammalian brain. In this review, we describe molecular interactions between Lin28 and let-7 and the biological role that each plays in implementing stem cell programs that either maintain stem cell self-renewal and plasticity or drive lineage commitment and differentiation. For Lin28, considerable progress has been made in defining let-7-dependent and let-7-independent functions in the maintenance of pluripotency, somatic cell reprogramming, tissue regeneration, and neural stem cell plasticity. For the pro-differentiation activity of let-7, we focus on emerging roles in mammalian neurogenesis and neuronal function. Specific targets and pathways for let-7 have been identified in embryonic and adult neurogenesis, including corticogenesis, retinal specification, and adult neurogenic niches. Special emphasis is given to examples of feedback and feedforward regulation, in particular within the miRNA biogenesis pathway.

Lin41/Trim71 is a heterochronic gene encoding a member of the Trim-NHL protein family, and is the original, genetically defined target of the microRNA let-7 in C. elegans. Both the LIN41 protein and multiple regulatory microRNA binding sites in the 3′ UTR of the mRNA are highly conserved from nematodes to humans. Functional studies have described essential roles for mouse LIN41 in embryonic stem cells, cellular reprogramming and the timing of embryonic neurogenesis. We have used a new gene trap mouse line deficient in Lin41 to characterize Lin41 expression during embryonic development and in the postnatal central nervous system (CNS). In the embryo, Lin41 is required for embryonic viability and neural tube closure. Nevertheless, neurosphere assays suggest that Lin41 is not required for adult neurogenesis. Instead, we show that Lin41 promoter activity and protein expression in the postnatal CNS is restricted to ependymal cells lining the walls of the four ventricles. We use ependymal cell culture to confirm reestablishment of Lin41 expression during differentiation of ependymal progenitors to post-mitotic cells possessing motile cilia. Our results reveal that terminally differentiated ependymal cells express Lin41, a gene to date associated with self-renewing stem cells.

BackgroundVancomycin-resistant enterococci (VRE) are among the most common antimicrobial-resistant pathogens causing nosocomial infections. Although antibiotic use has been identified as a risk factor for VRE, it remains unclear which antimicrobial agents particularly facilitate VRE selection. Here, we assessed whether use of specific antimicrobial agents is independently associated with healthcare-associated (HA) VRE rates in a university hospital setting in Berlin, Germany.MethodsWe conducted the study between January 2014 and December 2015 at the Charité-university hospital of Berlin, Germany. From the hospital pharmacy, we extracted data for all antibacterials for systemic use (anatomical therapeutic chemical (ATC)-classification J01) and calculated ward specific antibiotic consumption in defined daily doses (DDDs) per 100 patient-days (PD). We used the microbiology laboratory database to identify all patients with isolation of invasive or non-invasive VRE and calculated HA-VRE incidence as nosocomial VRE-cases per 100 patients and HA-VRE incidence density as nosocomial VRE-cases per 1000 PD. We defined VRE isolates as hospital-acquired if they were identified three days or later after hospital admission and otherwise as community-acquired (CA-VRE). We performed univariable and multivariable regression analyses to estimate the association of the frequency of HA-VRE per month with antibiotic use and other parameters such as length of stay, type of ward or presence of at least one CA-VRE on ward. In a second analysis, we considered only patients with VRE infections.ResultsWe included data from 204,054 patients with 948,380 PD from 61 wards. Overall, 1430 VRE-cases were identified of which 409 (28.6%) were considered hospital-acquired (HA). We found that carbapenem use in the current month and prior-month use of glycopeptides increased the risk for HA-VRE by 1% per 1 DDD/100 PD and 3% per 1 DDD/100 PD, respectively. However, when only VRE from clinical samples were considered, only glycopeptide use showed a statistically significant association. In both models, detection of at least one patient with CA-VRE on a ward in the current month significantly increased the risk of HA-VRE, thereby indicating nosocomial spread of VRE.ConclusionsOur findings suggest that the risk of HA-VRE is associated with specific antimicrobial agents. Prudent use of these antimicrobial agents might reduce nosocomial VRE rates. That appearance of at least one CA-VRE case on the ward increased the risk of HA-VRE detection highlights the importance of strict hand hygiene practices to interrupt person-to-person transmission of VRE.

Objectives To assess the admission prevalence of third-generation cephalosporin-resistant Enterobacterales (3GCREB) and to assess whether risk factors vary by β-lactamase genotype. Methods Adult patients were recruited within 72 h of admission to general wards of six university hospitals in 2014 and 2015. Rectal swabs were screened for 3GCREB and isolates were analysed phenotypically and genotypically. Patients were questioned on potential risk factors. Multivariable analyses were performed to identify risk factors for 3GCREB colonization and for specific β-lactamases. Results Of 8753 patients screened, 828 were 3GCREB positive (9.5%). Eight hundred and thirteen isolates were available for genotyping. CTX-M-15 was the most common ESBL (38.0%), followed by CTX-M-1 (22.5%), CTX-M-14 (8.7%), CTX-M-27 (7.5%) and SHV-ESBL (4.4%). AmpC was found in 11.9%. Interestingly, 18 Escherichia coli isolates were AmpC positive, 12 of which (67%) contained AmpC on a gene of plasmid origin [CMY (n = 10), DHA (n = 2)]. Risk factors for 3GCREB colonization varied by genotype. Recent antibiotic exposure and prior colonization by antibiotic-resistant bacteria were risk factors for all β-lactamases except CTX-M-14 and CTX-M-27. Travel outside Europe was a risk factor for CTX-M-15 and CTX-M-27 [adjusted OR (aOR) 3.49, 95% CI 2.88–4.24 and aOR 2.73, 95% CI 1.68–4.43]. A previous stay in a long-term care facility was associated with CTX-M-14 (aOR 3.01, 95% CI 1.98–4.59). A preceding hospital stay in Germany increased the risk of CTX-M-15 (aOR 1.27, 95% CI 1.14–1.41), while a prior hospital stay in other European countries increased the risk of SHV-ESBL colonization (aOR 3.85, 95% CI 1.67–8.92). Conclusions The detection of different ESBL types is associated with specific risk factor sets that might represent distinct sources of colonization and ESBL-specific dissemination routes.

BackgroundMany patients admitted to a hospital are already colonized with multi-drug resistant organisms (MDRO) including third-generation cephalosporin-resistant Enterobacteriaceae (3GCREB). The aim of our study was to determine the prevalence of rectal 3GCREB colonization at admission to a large German university hospital and to estimate infection incidences. In addition, risk factors for 3GCREB colonization were identified.Materials/MethodsIn 2014 and 2015, patients were screened for rectal colonization with 3GCREB and filled out a questionnaire on potential risk factors at admission to a non-intensive care unit (non-ICU). All patients were retrospectively monitored for bacterial infections. Descriptive, univariable and multivariable logistic regression analyses were conducted to identify risk factors for 3GCREB colonization at admission.ResultsOf 4,013 patients included, 10.3% (n = 415) were rectally colonized with 3GCREB at admission. Incidence of nosocomial infections was 3.5 (95% CI 2.0–6.1) per 100 patients rectally colonized with 3GCREB compared to 2.3 (95% CI 1.8–3.0, P = 0.213) per 100 3GCREB negative patients.Independent risk factors for 3GCREB colonization were prior colonization / infection with MDRO (OR 2.30, 95% CI 1.59–3.32), prior antimicrobial treatment (OR 1.97, 95% CI 1.59–2.45), male sex (OR 1.38, 95% CI 1.12–1.70), prior travelling outside Europe (OR 2.39, 95% CI 1.77–3.22) and places of residence in the Berlin districts Charlottenburg-Wilmersdorf (OR 1.52, 95% CI 1.06–2.18), Friedrichshain-Kreuzberg (OR 2.32, 95% CI 1.44–3.74) and Mitte (OR 1.73, 95% CI 1.26–2.36).ConclusionsAdmission prevalence of rectal colonization with 3GCREB was high, while infection incidence did not significantly differ between patients rectally colonized or not with 3GCREB at hospital admission. In consequence, hospitals should prioritize improvement of standard precautions including hand hygiene to prevent infections among all patients irrespective of their 3GCREB status at hospital admission.

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