Browsing by Author "Burton JP"

Now showing 1 - 6 of 6
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    Corrigendum: New perspectives on an old grouping: the genomic and phenotypic variability of Oxalobacter formigenes and the implications for calcium oxalate stone prevention.
    (Frontiers Media S.A., 2023-06-12) Chmiel JA; Carr C; Stuivenberg GA; Venema R; Chanyi RM; Al KF; Giguere D; Say H; Akouris PP; Domínguez Romero SA; Kwong A; Tai V; Koval SF; Razvi H; Bjazevic J; Burton JP
    [This corrects the article DOI: 10.3389/fmicb.2022.1011102.].
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    Inflatable Penile Prostheses Implantation: Does Antibiotic Exposure Matter?
    (Oxford University Press, 2018-09-01) Chanyi RM; Alzubaidi R; Leung EJY; Wilcox HB; Brock GB; Burton JP
    BACKGROUND: Inflatable penile prosthetic (IPP) infections are unusual but carry high patient morbidity and healthcare costs. AIM: To increase the bactericidal effect of IPP tubing material to prevent future bacterial infections and to determine whether this effect is time-dependent. METHODS: A modified disk diffusion assay was developed to measure the zones of inhibition against Escherichia coli, Proteus mirabilis, Staphylococcus aureus, and Staphylococcus epidermidis when tubing was immersed in gentamycin, ampicillin, tetracycline, kanamycin, erythromycin, or ciprofloxacin. To further assess the efficacy of this approach, IPP tubing was exposed to ampicillin or ciprofloxacin for 30 seconds, 2 minutes, 10 minutes, or 60 minutes. OUTCOMES: Bacterial zones of inhibition against IPP tubing material exposed to various treatments. RESULTS: IPP tubing was more effective against Gram-positive bacteria (S aureus and S epidermidis) then Gram-negative bacteria (E coli and P mirabilis). Immersing IPP tubing material in ampicillin or ciprofloxacin increased bactericidal effect of tubing material against Gram-positive and Gram-negative bacteria, respectively. The observed inhibitory effect was time dependent. CLINICAL TRANSLATION: Exposing IPP to a specific antimicrobial directly before implantation increases the bactericidal properties of the material, potentially decreasing the likelihood of infection. STRENGTHS & LIMITATIONS: This study is limited in that it is in vitro experimentation observing the effect of a single strain of each bacterium. Although the strains used were clinically relevant, further analysis is required to determine whether these results were strain specific. CONCLUSION: Immersing IPP material into an antibiotic solution, such as ampicillin or ciprofloxacin, increases the bactericidal properties and may aid in the prevention of infection.
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    Moving on from Metchnikoff: thinking about microbiome therapeutics in cancer.
    (ecancer Global Foundation, 2018-09-05) Maleki Vareki S; Chanyi RM; Abdur-Rashid K; Brennan L; Burton JP
    Precision medicine now needs to also consider the microbiome in oncology treatment. Ingested substances, whether they are a carcinogenic or therapeutic agent, will likely come into contact with the microbiota. Even those delivered extra-intestinally can be influenced beyond xenobiotic metabolism by biochemical factors associated with the microbiota or by an immunological predisposition created by the microbiome. We need to undertake one of the largest paradigm shifts to ever occur in medicine, that is, every drug or ingested substance needs to be re-evaluated for its pharmacological effect post-microbiome interaction. The importance of the microbiome with a focus on the treatment of cancer is discussed. In the near future, it may be possible to specifically manipulate the microbial composition within cancer patients to improve the therapeutic potential of existing oncological agents. However, the current tools to do so are limited. Targeted modulation is likely to be achieved by addition, selective enhancement or depletion of specific microbial types. This may include compounds such as narrow spectrum antimicrobial agents or oligosaccharides that will kill or enhance the bacterial growth of distinct members of the microbiota, respectively. This will stimulate a new era in these fields.
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    New perspectives on an old grouping: The genomic and phenotypic variability of Oxalobacter formigenes and the implications for calcium oxalate stone prevention.
    (Frontiers Media S.A., 2022-12-21) Chmiel JA; Carr C; Stuivenberg GA; Venema R; Chanyi RM; Al KF; Giguere D; Say H; Akouris PP; Domínguez Romero SA; Kwong A; Tai V; Koval SF; Razvi H; Bjazevic J; Burton JP; Sutcliffe I
    Oxalobacter formigenes is a unique bacterium with the ability to metabolize oxalate as a primary carbon source. Most kidney stones in humans are composed of calcium and oxalate. Therefore, supplementation with an oxalate-degrading bacterium may reduce stone burden in patients suffering from recurrent calcium oxalate-based urolithiasis. Strains of O. formigenes are divided into two groups: group I and group II. However, the differences between strains from each group remain unclear and elucidating these distinctions will provide a better understanding of their physiology and potential clinical applications. Here, genomes from multiple O. formigenes strains underwent whole genome sequencing followed by phylogenetic and functional analyses. Genetic differences suggest that the O. formigenes taxon should be divided into an additional three species: Oxalobacter aliiformigenes sp. nov, Oxalobacter paeniformigenes sp. nov, and Oxalobacter paraformigenes sp. nov. Despite the similarities in the oxalyl-CoA gene (oxc), which is essential for oxalate degradation, these strains have multiple unique genetic features that may be potential exploited for clinical use. Further investigation into the growth of these strains in a simulated fecal environment revealed that O. aliiformigenes strains are capable of thriving within the human gut microbiota. O. aliiformigenes may be a better therapeutic candidate than current group I strains (retaining the name O. formigenes), which have been previously tested and shown to be ineffective as an oral supplement to mitigate stone disease. By performing genomic analyses and identifying these novel characteristics, Oxalobacter strains better suited to mitigation of calcium oxalate-based urolithiasis may be identified in the future.
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    Oxalate-Degrading Bacillus subtilis Mitigates Urolithiasis in a Drosophila melanogaster Model.
    (American Society for Microbiology, 2020-10-01) Al KF; Daisley BA; Chanyi RM; Bjazevic J; Razvi H; Reid G; Burton JP
    Kidney stones affect nearly 10% of the population in North America and are associated with high morbidity and recurrence, yet novel prevention strategies are lacking. Recent evidence suggests that the human gut microbiota can influence the development of nephrolithiasis, although clinical trials have been limited and inconclusive in determining the potential for microbially based interventions. Here, we used an established Drosophila melanogaster model of urolithiasis as a high-throughput screening platform for evaluation of the therapeutic potential of oxalate-degrading bacteria in calcium oxalate (CaOx) nephrolithiasis. The results demonstrated that Bacillus subtilis 168 (BS168) is a promising candidate based on its preferential growth in high oxalate concentrations, its ability to stably colonize the D. melanogaster intestinal tract for as long as 5 days, and its prevention of oxalate-induced microbiota dysbiosis. Single-dose BS168 supplementation exerted beneficial effects on D. melanogaster for as long as 14 days, decreasing stone burden in dissected Malpighian tubules and fecal excreta while increasing survival and behavioral markers of health over those of nonsupplemented lithogenic controls. These findings were complemented by in vitro experiments using the established MDCK renal cell line, which demonstrated that BS168 pretreatment prevented increased CaOx crystal adhesion and aggregation. Taking our results together, this study supports the notion that BS168 can functionally reduce CaOx stone burden in vivo through its capacity for oxalate degradation. Given the favorable safety profile of many B. subtilis strains already used as digestive aids and in fermented foods, these findings suggest that BS168 could represent a novel therapeutic adjunct to reduce the incidence of recurrent CaOx nephrolithiasis in high-risk patients.IMPORTANCE Kidney stone disease is a morbid condition that is increasing in prevalence, with few nonsurgical treatment options. The majority of stones are composed of calcium oxalate. Unlike humans, some microbes can break down oxalate, suggesting that microbial therapeutics may provide a novel treatment for kidney stone patients. This study demonstrated that Bacillus subtilis 168 (BS168) decreased stone burden, improved health, and complemented the microbiota in a Drosophila melanogaster urolithiasis model, while not exacerbating calcium oxalate aggregation or adhesion to renal cells in vitro These results identify this bacterium as a candidate for ameliorating stone formation; given that other strains of B. subtilis are components of fermented foods and are used as probiotics for digestive health, strain 168 warrants testing in humans. With the severe burden that recurrent kidney stone disease imposes on patients and the health care system, this microbial therapeutic approach could provide an inexpensive therapeutic adjunct.
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    Streptococcus salivarius inhibits immune activation by periodontal disease pathogens
    (BioMed Central Ltd, 2021-05-07) MacDonald KW; Chanyi RM; Macklaim JM; Cadieux PA; Reid G; Burton JP
    BACKGROUND: Periodontal disease represents a major health concern. The administration of beneficial microbes has been increasing in popularity over efforts to manipulate the microbes using antimicrobial agents. This study determined the ability of Streptococcus salivarius to inhibit IL-6 and IL-8 production by gingival fibroblasts when activated by periodontal pathogens and their effect on the salivary microbiome. METHODS: Primary human gingival fibroblasts were challenged with Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum and a combination of all three. IL-6 and IL-8 cytokine release were measured. Using this same model, S. salivarius K12, M18 and different supernatant and whole-cell lysate fractions of S. salivarius K12 were administered to pathogen-induced fibroblasts. A patient study of healthy participants was also conducted to determine the effect S. salivarius K12 had on the native microbiome using 16S next generation sequence analysis. RESULTS: All pathogens tested induced a significant IL-6 and IL-8 response. S. salivarius K12 or M18, did not exhibit an increase in inflammatory cytokines. When either of the probiotic strains were co-administered with a pathogen, there were significant reductions in both IL-6 and IL-8 release. This effect was also observed when gingival fibroblasts were pre-treated with either S. salivarius K12 or M18 and then stimulated with the oral pathogens. Chewing gum containing S. salivarius K12 did not alter the salivary microbiome and did not increase inflammatory markers in the oral cavity. CONCLUSION: S. salivarius K12 and M18 prevented immune activation induced by periodontal disease pathogens. S. salivarius K12 did not alter the salivary microbiome or induce immune activation when administered as a chewing gum. These results warrant further study to determine if it may be an effective treatment in a model of periodontal disease.