12 research outputs found

    Bacterial genome sequencing tracks the housefly-associated dispersal of fluoroquinolone- and cephalosporin-resistant Escherichia coli from a pig farm

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    The regular use of antimicrobials in livestock production selects for antimicrobial resistance. The potential impact of this practice on human health needs to be studied in more detail, including the role of the environment for the persistence and transmission of antimicrobial-resistant bacteria. During an investigation of a pig farm and its surroundings in Brandenburg, Germany, we detected abundant cephalosporin- and fluoroquinolone-resistant Escherichia coli in pig faeces, sedimented dust, and house flies (Musca domestica). Genome sequencing of E. coli isolates revealed large phylogenetic diversity and plasmid-borne extended-spectrum beta lactamase (ESBL) genes CTX-M-1 in multiple strains. [Correction added on 28 February 2023, after first online publication: In the preceding sentence, ‘and TEM-1’ was previously included but has been deleted in this version.] Close genomic relationships indicated frequent transmission of antimicrobial-resistant E. coli between pigs from different herds and across buildings of the farm and suggested dust and flies as vectors for dissemination of faecal pathogens. Strikingly, we repeatedly recovered E. coli from flies collected up to 2 km away from the source, whose genome sequences were identical or closely related to those from pig faeces isolates, indicating the fly-associated transport of diverse ESBL-producing E. coli from the pig farm into urban habitation areas. The observed proximity of contaminated flies to human households poses a risk of transmission of antimicrobial-resistant enteric pathogens from livestock to man

    Improvements of weaned pigs barn hygiene to reduce the spread of antimicrobial resistance

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    The spread of antimicrobial resistance (AMR) in animal husbandry is usually attributed to the use of antibiotics and poor hygiene and biosecurity. We therefore conducted experimental trials to improve hygiene management in weaned pig houses and assessed the impact on the spread. For each of the two groups examined, the experimental group (EG) and the control group (CG), three replicate batches of piglets from the same pig breeder, kept in pre-cleaned flat decks, were analyzed. In the flat decks of the experimental groups, the hygiene conditions (cleaning, disinfection, dust removal and fly control) were improved, while regular hygiene measures were carried out in the control groups. The occurrence and spread of AMR were determined in Escherichia coli (E. coli; resistance indicator) using cultivation-dependent (CFU) and -independent (qPCR) methods as well as whole genome sequencing of isolates in samples of various origins, including feces, flies, feed, dust and swabs. Surprisingly, there were no significant differences (p > 0.05) in the prevalence of resistant E. coli between the flat decks managed with conventional techniques and those managed with improved techniques. Selective cultivation delivered ampicillin- and sulfonamide-resistant E. coli proportions of up to 100% and 1.2%, respectively. While 0.5% E. coli resistant to cefotaxime and no ciprofloxacin resistance were detected. There was a significant difference (p < 0.01) in the abundance of the blaTEM-1 gene in fecal samples between EG and CG groups. The colonization of piglets with resistant pathogens before arrival, the movement of flies in the barn and the treatment of bacterial infections with antibiotics obscured the effects of hygiene improvement. Biocide tolerance tests showed no development of resistance to the farm regular disinfectant. Managing hygiene alone was insufficient for reducing antimicrobial resistances in piglet rearing. We conclude that the complex factors contributing to the presence and distribution of AMR in piglet barns underscore the necessity for a comprehensive management strategy

    Mobile Air Quality Studies (MAQS) - an international project

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    Due to an increasing awareness of the potential hazardousness of air pollutants, new laws, rules and guidelines have recently been implemented globally. In this respect, numerous studies have addressed traffic-related exposure to particulate matter using stationary technology so far. By contrast, only few studies used the advanced technology of mobile exposure analysis. The Mobile Air Quality Study (MAQS) addresses the issue of air pollutant exposure by combining advanced high-granularity spatial-temporal analysis with vehicle-mounted, person-mounted and roadside sensors. The MAQS-platform will be used by international collaborators in order 1) to assess air pollutant exposure in relation to road structure, 2) to assess air pollutant exposure in relation to traffic density, 3) to assess air pollutant exposure in relation to weather conditions, 4) to compare exposure within vehicles between front and back seat (children) positions, and 5) to evaluate "traffic zone"- exposure in relation to non-"traffic zone"-exposure. Primarily, the MAQS-platform will focus on particulate matter. With the establishment of advanced mobile analysis tools, it is planed to extend the analysis to other pollutants including including NO2, SO2, nanoparticles, and ozone

    Analysis of the Ion Channel Gating Mechanism in Solution by Nuclear Magnetic Resonance (NMR) Spectroscopy

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    Ion channels activated by cyclic nucleotides play crucial roles in signal transduction pathways. Upon binding of cyclic nucleotides to the intracellular cyclic nucleotide-binding domain (CNBD) of HCN or CNG channels (hyperpolarization-activated and cyclic nucleotide-gated channels or cyclic nucleotide-gated channels) an opening of the membrane pore occurs.To analyze the underlying gating mechanism highly resolved structures of the cyclic nucleotide-binding domains are necessary. Until now, structures of CNBDs from eukaryotic HCN channels as well as prokaryotic CNG channels are known. However, CNBD crystal structures of the HCN channels reveal no significant differences between apo and holo state1,2. In contrast, CNBD structures of the prokaryotic Mesorhizobium loti K1 channel, solved by liquid state NMR spectroscopy, show substantial rearrangements upon binding of a cyclic nucleotide3,4.Further elucidation of the gating mechanism will be done by structural analysis of an eukaryotic CNBD using liquid state NMR spectroscopy

    Schule in Farbigen ZustĂ€nden - Lernmodule fĂŒr den 5. Jahrgang

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    Deutsche Forschungsgemeinschaft (DFG)Mit dem Ziel, frĂŒhzeitig Interesse an Technik und Naturwissenschaften zu fördern, kooperierte der Sonderforschungsbereich SFB 1232 „Farbige ZustĂ€nde“, UniversitĂ€t Bremen, mit einer Oberschule. FĂŒr eine Profilklasse gestalteten LehrkrĂ€fte und Wissenschaftler*innen gemeinsam forschendes Lernen. Die im 5. Jahrgang durchgefĂŒhrten Unterrichtseinheiten sind hier mit Arbeitsmaterial und AblaufplĂ€nen fĂŒr LehrkrĂ€fte als Blaupause zusammengefasst

    Encouragement of patients’ self-management in primary care for the prevention of cardiovascular diseases (DECADE): protocol for a cluster randomised controlled trial

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    Introduction Cardiovascular diseases are the most common cause of death in Germany and among the most frequent reasons for encounters in primary care. Most patients with cardiovascular risks (CVRs) have difficulties implementing health-promoting behavioural changes. In this study, a complex intervention containing evidence-based patient materials and structured follow-up consultations are intended to strengthen patients’ self-management to improve health behaviour.Methods and analysis In this cluster randomised controlled trial, we investigate the effects of the intervention Decision aid, action planning and follow-up support for patients to reduce the 10-year risk of cardiovascular diseases (DECADE) using a 2×2 design. All patients, including the control group (CG), receive a CVR calculation. Three intervention groups (IGs) receive one or both of two different components of the DECADE intervention: IG1 (patient materials), IG2 (follow-up consultations) and IG3 (patient materials and follow-up consultations). The study was planned to be conducted with 77 general practitioners in 3 German regions and a target sample size of 924 patients. The observation period for each patient amounts to 12 months with three patient surveys: baseline (t0), after 6 and 12 months (t1 and t2). The primary outcome is patient activation (Patient Activation Measure 13 (PAM13-D)) at t1. Secondary outcomes include PAM13-D at t2 and further patient-reported and clinical outcomes at t1 and t2. We will also analyse the cost-effectiveness of the intervention, the degree of usage and satisfaction with the intervention.Ethics and dissemination The study was first approved by the lead ethics committee of the University of Freiburg on 15 April 2021 (vote number: 21-1078) and subsequently by the other ethics committees in the study regions (Ethics committee of medical association Baden-WĂŒrttemberg (B-F-2021-078), Ethics Committee of the Technische UniversitĂ€t Dresden, Dresden (BO-EK-251052021), Ethics Committee of the State Chamber of Physicians of Saxony (EK-BR-92/21-1), Ethics Committee of the Hamburg Medical Association (2021-200013-BO-bet)). Informed consent is required for patients to participate in the study. The results of this study will be published in peer-reviewed journals and presented at congresses by the DECADE team. The DECADE lead management will communicate the results to the funder of this study.Trial registration number German Clinical Trials Register, DRKS00025401 (registration date: 21 June 2021); International Clinical Trials Registry Platform, DRKS00025401

    Supplementary information files for Cell culture-derived extracellular vesicles: Considerations for reporting cell culturing parameters

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    Supplementary files for article Cell culture-derived extracellular vesicles: Considerations for reporting cell culturing parametersCell culture‐conditioned medium (CCM) is a valuable source of extracellular vesicles (EVs) for basic scientific, therapeutic and diagnostic applications. Cell culturing parameters affect the biochemical composition, release and possibly the function of CCM‐derived EVs (CCM‐EV). The CCM‐EV task force of the Rigor and Standardization Subcommittee of the International Society for Extracellular Vesicles aims to identify relevant cell culturing parameters, describe their effects based on current knowledge, recommend reporting parameters and identify outstanding questions. While some recommendations are valid for all cell types, cell‐specific recommendations may need to be established for non‐mammalian sources, such as bacteria, yeast and plant cells. Current progress towards these goals is summarized in this perspective paper, along with a checklist to facilitate transparent reporting of cell culturing parameters to improve the reproducibility of CCM‐EV research.</p
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