12 research outputs found

    Energetics and Mechanism of Drug Transport Mediated by the Lactococcal Multidrug Transporter LmrP

    Get PDF
    The gene encoding the secondary multidrug transporter LmrP of Lactococcus lactis was heterologously expressed in Escherichia coli. The energetics and mechanism of drug extrusion mediated by LmrP were studied in membrane vesicles of E. coli. LmrP-mediated extrusion of tetraphenyl phosphonium (TPP+) from right-side-out membrane vesicles and uptake of the fluorescent membrane probe 1-[4-(trimethylamino)phenyl]-6-phenylhexa-1,3,5-triene (TMA-DPH) into inside-out membrane vesicles are driven by the membrane potential (Δψ) and the transmembrane proton gradient (ΔpH), pointing to an electrogenic drug/proton antiport mechanism. Ethidium bromide, a substrate for LmrP, inhibited the LmrP-mediated TPP+ extrusion from right-sideout membrane vesicles, showing that LmrP is capable of transporting structurally unrelated drugs. Kinetic analysis of LmrP-mediated TMA-DPH transport revealed a direct relation between the transport rate and the amount of TMA-DPH associated with the cytoplasmic leaflet of the lipid bilayer. This observation indicates that drugs are extruded from the inner leaflet of the cytoplasmic membrane into the external medium. This is the first report that shows that drug extrusion by a secondary multidrug resistance (MDR) transporter occurs by a “hydrophobic vacuum cleaner” mechanism in a similar way as was proposed for the primary lactococcal MDR transporter, LmrA.

    The war on street 'terror': why tackle anti-social behaviour?

    Full text link
    This article examines the rationales of Dutch politicians for tackling the perceived pressing problem of 'anti-social behaviour' (ASB) and the question did they copy the British approach? The first part will describe in short the concept of policy transfer and the recent British fight against ASB. The focus will be on the introduction of the Anti-social Behaviour Order. The second part is an empirical study into the Dutch retreat from 'condoning' ASB, consisting of interviews with Dutch politicians focusing on their ideas for tackling ASB. Those are compared with the British's rationales. This kind of comparative elite ethnography is not common in criminology, but this article aims at providing evidence of its benefits. By answering the research question an insight into the origins of policy in the sphere of criminal justice can be obtained

    Prolonged COVID-19 symptom duration in people with systemic autoimmune rheumatic diseases: results from the COVID-19 Global Rheumatology Alliance Vaccine Survey

    Get PDF
    OBJECTIVE: We investigated prolonged COVID-19 symptom duration, defined as lasting 28 days or longer, among people with systemic autoimmune rheumatic diseases (SARDs). METHODS: We analysed data from the COVID-19 Global Rheumatology Alliance Vaccine Survey (2 April 2021-15 October 2021) to identify people with SARDs reporting test-confirmed COVID-19. Participants reported COVID-19 severity and symptom duration, sociodemographics and clinical characteristics. We reported the proportion experiencing prolonged symptom duration and investigated associations with baseline characteristics using logistic regression. RESULTS: We identified 441 respondents with SARDs and COVID-19 (mean age 48.2 years, 83.7% female, 39.5% rheumatoid arthritis). The median COVID-19 symptom duration was 15 days (IQR 7, 25). Overall, 107 (24.2%) respondents had prolonged symptom duration (≄28 days); 42/429 (9.8%) reported symptoms lasting ≄90 days. Factors associated with higher odds of prolonged symptom duration included: hospitalisation for COVID-19 vs not hospitalised and mild acute symptoms (age-adjusted OR (aOR) 6.49, 95% CI 3.03 to 14.1), comorbidity count (aOR 1.11 per comorbidity, 95% CI 1.02 to 1.21) and osteoarthritis (aOR 2.11, 95% CI 1.01 to 4.27). COVID-19 onset in 2021 vs June 2020 or earlier was associated with lower odds of prolonged symptom duration (aOR 0.42, 95% CI 0.21 to 0.81). CONCLUSION: Most people with SARDs had complete symptom resolution by day 15 after COVID-19 onset. However, about 1 in 4 experienced COVID-19 symptom duration 28 days or longer; 1 in 10 experienced symptoms 90 days or longer. Future studies are needed to investigate the possible relationships between immunomodulating medications, SARD type/flare, vaccine doses and novel viral variants with prolonged COVID-19 symptoms and other postacute sequelae of COVID-19 among people with SARDs

    Molecular characterization and antibiotic specificities of multidrug transporters in Lactoccus lactis

    Get PDF
    Many infectious diseases caused by various pathogenic bacteria can often successfully be treated with antibiotics. however, a major drawback of the widespread use of antibiotics is the selection of antibiotic resistant bacteria. Consequently, bacterial diseases that were believed to be controlled, are re-emerging. ... Zie: Summary
    corecore