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  1. Article ; Online: Infection responsive coatings to reduce biofilm formation and encrustation of urinary catheters.

    Slate, Anthony J / Clarke, Ocean E / Kerio, Mina / Nzakizwanayo, Jonathan / Patel, Bhavik Anil / Jones, Brian V

    Journal of applied microbiology

    2023  Volume 134, Issue 6

    Abstract: Aims: The care of patients undergoing long-term urethral catheterization is frequently complicated by Proteus mirabilis infection. This organism forms dense, crystalline biofilms, which block catheters leading to serious clinical conditions. However, ... ...

    Abstract Aims: The care of patients undergoing long-term urethral catheterization is frequently complicated by Proteus mirabilis infection. This organism forms dense, crystalline biofilms, which block catheters leading to serious clinical conditions. However, there are currently no truly effective approaches to control this problem. Here, we describe the development of a novel theranostic catheter coating, to simultaneously provide early warning of blockage, and actively delay crystalline biofilm formation.
    Methods and results: The coating comprises of a pH sensitive upper polymer layer (poly(methyl methacrylate-co-methacrylic acid); Eudragit S 100®) and a hydrogel base layer of poly(vinyl alcohol), which is loaded with therapeutic agents (acetohydroxamic acid or ciprofloxacin hydrochloride) and a fluorescent dye, 5(6)-carboxyfluorescein (CF). The elevation of urinary pH due to P. mirabilis urease activity results in the dissolution of the upper layer and release of cargo agents contained in the base layer. Experiments using in vitro models, which were representative of P. mirabilis catheter-associated urinary tract infections, demonstrated that these coatings significantly delay time taken for catheters to block. Coatings containing both CF dye and ciprofloxacin HCl were able to provide an average of ca. 79 h advanced warning of blockage and extend catheter lifespan ca. 3.40-fold.
    Conclusions: This study has demonstrated the potential for theranostic, infection-responsive coatings to form a promising approach to combat catheter encrustation and actively delay blockage.
    MeSH term(s) Humans ; Urinary Catheters ; Urinary Catheterization/adverse effects ; Proteus Infections/prevention & control ; Proteus Infections/etiology ; Proteus mirabilis ; Urinary Tract Infections/prevention & control ; Biofilms
    Chemical Substances 6-carboxyfluorescein (3301-79-9)
    Language English
    Publishing date 2023-06-08
    Publishing country England
    Document type Journal Article
    ZDB-ID 1358023-1
    ISSN 1365-2672 ; 1364-5072
    ISSN (online) 1365-2672
    ISSN 1364-5072
    DOI 10.1093/jambio/lxad121
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: An In Vitro Bladder Model for Studying Catheter-Associated Urinary Tract Infection and Associated Analysis of Biofilms.

    Nzakizwanayo, Jonathan / Pelling, Harriet / Milo, Scarlet / Jones, Brian V

    Methods in molecular biology (Clifton, N.J.)

    2019  Volume 2021, Page(s) 139–158

    Abstract: Urethral catheters are among the most widely used medical devices, applied to manage a wide range of conditions in hospital, community, and care home settings. In long-term catheterized individuals, infection with Proteus mirabilis frequently complicates ...

    Abstract Urethral catheters are among the most widely used medical devices, applied to manage a wide range of conditions in hospital, community, and care home settings. In long-term catheterized individuals, infection with Proteus mirabilis frequently complicates the care of patients owing to formation of extensive crystalline biofilms. Here we describe the use of an in vitro bladder model of the catheterized urinary tract and associated analyses to study P. mirabilis crystalline biofilm formation. The model originally described by Stickler et al. (1999, 310:494-501, Methods Enzymol) replicates a complete sterile closed drainage system as used in clinical practice, and permits formation of biofilms directly on catheters under conditions representative of those encountered in vivo. Models may be used to replicate either established infection or early stage colonization, and we describe a range of associated methods for quantification and visualization of biofilms formed on catheters. These methods are also easily adapted to study catheter-associated biofilm formation by other urinary tract pathogens.
    MeSH term(s) Bacteriological Techniques ; Biofilms ; Catheter-Related Infections/diagnosis ; Humans ; In Vitro Techniques ; Models, Biological ; Proteus Infections/diagnosis ; Proteus mirabilis/isolation & purification ; Proteus mirabilis/physiology ; Urinary Catheters/microbiology ; Urinary Tract Infections/microbiology
    Language English
    Publishing date 2019-07-15
    Publishing country United States
    Document type Journal Article
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-4939-9601-8_14
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Emerging medical and engineering strategies for the prevention of long-term indwelling catheter blockage.

    Milo, Scarlet / Nzakizwanayo, Jonathan / Hathaway, Hollie J / Jones, Brian V / Jenkins, A Toby A

    Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine

    2018  Volume 233, Issue 1, Page(s) 68–83

    Abstract: Urinary catheters have been used on an intermittent or indwelling basis for centuries, in order to relieve urinary retention and incontinence. Nevertheless, the use of urinary catheters in the clinical setting is fraught with complication, the most ... ...

    Abstract Urinary catheters have been used on an intermittent or indwelling basis for centuries, in order to relieve urinary retention and incontinence. Nevertheless, the use of urinary catheters in the clinical setting is fraught with complication, the most common of which is the development of nosocomial urinary tract infections, known as catheter-associated urinary tract infections. Infections of this nature are not only significant owing to their high incidence rate and subsequent economic burden but also to the severe medical consecutions that result. A range of techniques have been employed in recent years, utilising various technologies in attempts to counteract the perilous medical cascade following catheter blockage. This review will focus on the current advancement (within the last 10 years) in prevention of encrustation and blockage of long-term indwelling catheters both from engineering and medical perspectives, with particular emphasis on the importance of stimuli-responsive systems.
    MeSH term(s) Anti-Bacterial Agents/pharmacology ; Catheters, Indwelling/adverse effects ; Engineering/methods ; Equipment Failure ; Humans ; Urinary Catheters
    Chemical Substances Anti-Bacterial Agents
    Language English
    Publishing date 2018-05-28
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 1065942-0
    ISSN 2041-3033 ; 0046-2039 ; 0954-4119
    ISSN (online) 2041-3033
    ISSN 0046-2039 ; 0954-4119
    DOI 10.1177/0954411918776691
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  4. Article ; Online: Antibiotic Therapy and the Gut Microbiome: Investigating the Effect of Delivery Route on Gut Pathogens.

    Kelly, Stephen A / Nzakizwanayo, Jonathan / Rodgers, Aoife M / Zhao, Li / Weiser, Rebecca / Tekko, Ismaiel A / McCarthy, Helen O / Ingram, Rebecca J / Jones, Brian V / Donnelly, Ryan F / Gilmore, Brendan F

    ACS infectious diseases

    2021  Volume 7, Issue 5, Page(s) 1283–1296

    Abstract: The contribution of the gut microbiome to human health has long been established, with normal gut microbiota conferring protection against invasive pathogens. Antibiotics can disrupt the microbial balance of the gut, resulting in disease and the ... ...

    Abstract The contribution of the gut microbiome to human health has long been established, with normal gut microbiota conferring protection against invasive pathogens. Antibiotics can disrupt the microbial balance of the gut, resulting in disease and the development of antimicrobial resistance. The effect of antibiotic administration route on gut dysbiosis remains under-studied to date, with conflicting evidence on the differential effects of oral and parenteral delivery. We have profiled the rat gut microbiome following treatment with commonly prescribed antibiotics (amoxicillin and levofloxacin), via either oral or intravenous administration. Fecal pellets were collected over a 13-day period and bacterial populations were analyzed by 16S rRNA gene sequencing. Significant dysbiosis was observed in all treatment groups, regardless of administration route. More profound dysbiotic effects were observed following amoxicillin treatment than those with levofloxacin, with population richness and diversity significantly reduced, regardless of delivery route. The effect on specific taxonomic groups was assessed, revealing significant disruption following treatment with both antibiotics. Enrichment of a number of groups containing known gut pathogens was observed, in particular, with amoxicillin, such as the family Enterobacteriaceae. Depletion of other commensal groups was also observed. The degree of dysbiosis was significantly reduced toward the end of the sampling period, as bacterial populations began to return to pretreatment composition. Richness and diversity levels appeared to return to pretreatment levels more quickly in intravenous groups, suggesting convenient parenteral delivery systems may have a role to play in reducing longer term gut dysbiosis in the treatment of infection.
    MeSH term(s) Animals ; Anti-Bacterial Agents ; Dysbiosis/chemically induced ; Enterobacteriaceae ; Gastrointestinal Microbiome ; RNA, Ribosomal, 16S/genetics ; Rats
    Chemical Substances Anti-Bacterial Agents ; RNA, Ribosomal, 16S
    Language English
    Publishing date 2021-04-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2373-8227
    ISSN (online) 2373-8227
    DOI 10.1021/acsinfecdis.1c00081
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: An in-situ infection detection sensor coating for urinary catheters.

    Milo, Scarlet / Thet, Naing Tun / Liu, Dan / Nzakizwanayo, Jonathan / Jones, Brian V / Jenkins, A Toby A

    Biosensors & bioelectronics

    2016  Volume 81, Page(s) 166–172

    Abstract: We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for ... ...

    Abstract We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage.
    MeSH term(s) Biosensing Techniques/methods ; Catheter-Related Infections/diagnosis ; Coated Materials, Biocompatible/chemistry ; Delayed-Action Preparations/chemistry ; Fluoresceins/administration & dosage ; Fluoresceins/analysis ; Fluorescent Dyes/administration & dosage ; Fluorescent Dyes/analysis ; Humans ; Hydrogels/chemistry ; Hydrogen-Ion Concentration ; Polymethacrylic Acids/chemistry ; Proteus Infections/diagnosis ; Proteus mirabilis/isolation & purification ; Urinary Catheters/adverse effects ; Urinary Tract Infections/diagnosis
    Chemical Substances Coated Materials, Biocompatible ; Delayed-Action Preparations ; Fluoresceins ; Fluorescent Dyes ; Hydrogels ; Polymethacrylic Acids ; methylmethacrylate-methacrylic acid copolymer (25086-15-1) ; 6-carboxyfluorescein (3301-79-9)
    Language English
    Publishing date 2016-02-26
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1011023-9
    ISSN 1873-4235 ; 0956-5663
    ISSN (online) 1873-4235
    ISSN 0956-5663
    DOI 10.1016/j.bios.2016.02.059
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  6. Article: Genomic and Ecogenomic Characterization of

    Alves, Diana R / Nzakizwanayo, Jonathan / Dedi, Cinzia / Olympiou, Chara / Hanin, Aurélie / Kot, Witold / Hansen, Lars / Lametsch, Rene / Gahan, Cormac G M / Schellenberger, Pascale / Ogilvie, Lesley A / Jones, Brian V

    Frontiers in microbiology

    2019  Volume 10, Page(s) 1783

    Abstract: ... Proteus ... ...

    Abstract Proteus mirabilis
    Language English
    Publishing date 2019-08-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2587354-4
    ISSN 1664-302X
    ISSN 1664-302X
    DOI 10.3389/fmicb.2019.01783
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  7. Article ; Online: Escherichia coli Nissle 1917 enhances bioavailability of serotonin in gut tissues through modulation of synthesis and clearance.

    Nzakizwanayo, Jonathan / Dedi, Cinzia / Standen, Guy / Macfarlane, Wendy M / Patel, Bhavik A / Jones, Brian V

    Scientific reports

    2015  Volume 5, Page(s) 17324

    Abstract: Accumulating evidence shows indigenous gut microbes can interact with the human host through modulation of serotonin (5-HT) signaling. Here we investigate the impact of the probiotic Escherichia coli Nissle 1917 (EcN) on 5-HT signalling in gut tissues. ... ...

    Abstract Accumulating evidence shows indigenous gut microbes can interact with the human host through modulation of serotonin (5-HT) signaling. Here we investigate the impact of the probiotic Escherichia coli Nissle 1917 (EcN) on 5-HT signalling in gut tissues. Ex-vivo mouse ileal tissue sections were treated with either EcN or the human gut commensal MG1655, and effects on levels of 5-HT, precursors, and metabolites, were evaluated using amperometry and high performance liquid chromatography with electrochemical detection (HPLC-EC). Exposure of tissue to EcN cells, but not MG1655 cells, was found to increase levels of extra-cellular 5-HT. These effects were not observed when tissues were treated with cell-free supernatant from bacterial cultures. In contrast, when supernatant recovered from untreated ileal tissue was pre-incubated with EcN, the derivative cell-free supernatant was able to elevate 5-HT overflow when used to treat fresh ileal tissue. Measurement of 5-HT precursors and metabolites indicated EcN also increases intracellular 5-HTP and reduces 5-HIAA. The former pointed to modulation of tryptophan hydroxylase-1 to enhance 5-HT synthesis, while the latter indicates an impact on clearance into enterocytes through SERT. Taken together, these findings show EcN is able to enhance 5-HT bioavailability in ileal tissues through interaction with compounds secreted from host tissues.
    MeSH term(s) Animals ; Biological Availability ; Escherichia coli/physiology ; Extracellular Space/metabolism ; Fatty Acids/metabolism ; Gastrointestinal Tract/metabolism ; Gastrointestinal Tract/microbiology ; Male ; Mice ; Models, Biological ; Serotonin/metabolism ; Serotonin/pharmacokinetics ; Synaptic Transmission
    Chemical Substances Fatty Acids ; Serotonin (333DO1RDJY)
    Language English
    Publishing date 2015-11-30
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/srep17324
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  8. Article ; Online: Prevention of encrustation and blockage of urinary catheters by Proteus mirabilis via pH-triggered release of bacteriophage.

    Milo, Scarlet / Hathaway, Hollie / Nzakizwanayo, Jonathan / Alves, Diana R / Esteban, Patricia Pérez / Jones, Brian V / Jenkins, A Toby A

    Journal of materials chemistry. B

    2017  Volume 5, Issue 27, Page(s) 5403–5411

    Abstract: The crystalline biofilms of Proteus mirabilis can seriously complicate the care of patients undergoing long-term indwelling urinary catheterisation. Expression of bacterial urease causes a significant increase in urinary pH, leading to the ... ...

    Abstract The crystalline biofilms of Proteus mirabilis can seriously complicate the care of patients undergoing long-term indwelling urinary catheterisation. Expression of bacterial urease causes a significant increase in urinary pH, leading to the supersaturation and precipitation of struvite and apatite crystals. These crystals become lodged within the biofilm, resulting in the blockage of urine flow through the catheter. Here, we describe an infection-responsive surface coating for urinary catheters, which releases a therapeutic dose of bacteriophage in response to elevated urinary pH, in order to delay catheter blockage. The coating employs a dual-layered system comprising of a lower hydrogel 'reservoir' layer impregnated with bacteriophage, capped by a 'trigger' layer of the pH-responsive polymer poly(methyl methacrylate-co-methacrylic acid) (EUDRAGIT®S 100). Evaluation of prototype coatings using a clinically reflective in vitro bladder model system showed that catheter blockage time was doubled (13 h to 26 h (P < 0.05)) under conditions of established infection (10
    Language English
    Publishing date 2017-06-27
    Publishing country England
    Document type Journal Article
    ZDB-ID 2702241-9
    ISSN 2050-7518 ; 2050-750X
    ISSN (online) 2050-7518
    ISSN 2050-750X
    DOI 10.1039/c7tb01302g
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  9. Article ; Online: Resolution of habitat-associated ecogenomic signatures in bacteriophage genomes and application to microbial source tracking.

    Ogilvie, Lesley A / Nzakizwanayo, Jonathan / Guppy, Fergus M / Dedi, Cinzia / Diston, David / Taylor, Huw / Ebdon, James / Jones, Brian V

    The ISME journal

    2017  Volume 12, Issue 4, Page(s) 942–958

    Abstract: Just as the expansion in genome sequencing has revealed and permitted the exploitation of phylogenetic signals embedded in bacterial genomes, the application of metagenomics has begun to provide similar insights at the ecosystem level for microbial ... ...

    Abstract Just as the expansion in genome sequencing has revealed and permitted the exploitation of phylogenetic signals embedded in bacterial genomes, the application of metagenomics has begun to provide similar insights at the ecosystem level for microbial communities. However, little is known regarding this aspect of bacteriophage associated with microbial ecosystems, and if phage encode discernible habitat-associated signals diagnostic of underlying microbiomes. Here we demonstrate that individual phage can encode clear habitat-related 'ecogenomic signatures', based on relative representation of phage-encoded gene homologues in metagenomic data sets. Furthermore, we show the ecogenomic signature encoded by the gut-associated ɸB124-14 can be used to segregate metagenomes according to environmental origin, and distinguish 'contaminated' environmental metagenomes (subject to simulated in silico human faecal pollution) from uncontaminated data sets. This indicates phage-encoded ecological signals likely possess sufficient discriminatory power for use in biotechnological applications, such as development of microbial source tracking tools for monitoring water quality.
    MeSH term(s) Bacteriophages/genetics ; Ecosystem ; Environmental Monitoring ; Feces/virology ; Gastrointestinal Tract/virology ; Genome, Viral ; Humans ; Metagenome ; Metagenomics ; Microbiota
    Language English
    Publishing date 2017-12-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2406536-5
    ISSN 1751-7370 ; 1751-7362
    ISSN (online) 1751-7370
    ISSN 1751-7362
    DOI 10.1038/s41396-017-0015-7
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  10. Article ; Online: The potential of nanoflow liquid chromatography-nano electrospray ionisation-mass spectrometry for global profiling the faecal metabolome.

    Chetwynd, Andrew J / Ogilvie, Lesley A / Nzakizwanayo, Jonathan / Pazdirek, Filip / Hoch, Jiří / Dedi, Cinzia / Gilbert, Duncan / Abdul-Sada, Alaa / Jones, Brian V / Hill, Elizabeth M

    Journal of chromatography. A

    2019  Volume 1600, Page(s) 127–136

    Abstract: Faeces are comprised of a wide array of metabolites arising from the circulatory system as well as the human microbiome. A global metabolite analysis (metabolomics) of faecal extracts offers the potential to uncover new compounds which may be indicative ... ...

    Abstract Faeces are comprised of a wide array of metabolites arising from the circulatory system as well as the human microbiome. A global metabolite analysis (metabolomics) of faecal extracts offers the potential to uncover new compounds which may be indicative of the onset of bowel diseases such as colorectal cancer (CRC). To date, faecal metabolomics is still in its infancy and the compounds of low abundance present in faecal extracts poorly characterised. In this study, extracts of faeces from healthy subjects were profiled using a sensitive nanoflow-nanospray LC-MS platform which resulted in highly repeatable peak retention times (<2% CV) and intensities (<15% CV). Analysis of the extracts revealed wide coverage of the faecal metabolome including detection of low abundant signalling compounds such as sex steroids and eicosanoids, alongside highly abundant pharmaceuticals and tetrapyrrole metabolites. A small pilot study investigating differences in metabolomics profiles of faecal samples obtained from 7 CRC, 25 adenomatous polyp and 26 healthy groups revealed that secondary bile acids, conjugated androgens, eicosanoids, phospholipids and an unidentified haem metabolite were potential classes of metabolites that discriminated between the CRC and control sample groups. However, much larger follow up studies are needed to confirm which components of the faecal metabolome are associated with actual CRC disease rather than dietary influences. This study reveals the potential of nanospray-nanoflow LC-MS profiling of faecal samples from large scale cohort studies for uncovering the role of the faecal metabolome in colorectal disease formation.
    MeSH term(s) Bile Acids and Salts/analysis ; Chromatography, Liquid ; Eicosanoids/analysis ; Feces/chemistry ; Female ; Healthy Volunteers ; Humans ; Male ; Metabolome ; Metabolomics ; Phospholipids/analysis ; Pilot Projects ; Spectrometry, Mass, Electrospray Ionization
    Chemical Substances Bile Acids and Salts ; Eicosanoids ; Phospholipids
    Language English
    Publishing date 2019-04-20
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1171488-8
    ISSN 1873-3778 ; 0021-9673
    ISSN (online) 1873-3778
    ISSN 0021-9673
    DOI 10.1016/j.chroma.2019.04.028
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