Publications by authors named "Andrew McDowell"

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) can misidentify Cutibacterium namnetense and Cutibacterium modestum as Cutibacterium acnes. We now describe how such MALDI-TOF MS misidentification explains previous reports of C. acnes isolates that could not be characterised using a multiplex PCR phylotyping assay.

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Radio frequency (RF) magnetometers based on nitrogen vacancy centers in diamond are predicted to offer femtotesla sensitivity, but previous experiments were limited to the picotesla level. We demonstrate a femtotesla RF magnetometer using a diamond membrane inserted between ferrite flux concentrators. The device provides ~300-fold amplitude enhancement for RF magnetic fields from 70 kHz to 3.

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Objectives: A 'high resolution' Single Locus Sequence Typing (SLST) scheme has been described for the anaerobic skin bacterium Cutibacterium acnes that seemingly discriminates sequence types (STs) to a level commensurate with previously described Multilocus Sequence Typing (MLST) methods (MLST; MLST; MLST). However, no quantifiable evaluation of SLST versus MLST for differentiation of C. acnes strains, especially in relation to the subspecies of the bacterium, known as C.

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Objectives: Using available whole genome data, the objective of this study was to identify genetic mechanisms that could explain the antimicrobial resistance profile of three multi-drug resistant (MDR) strains (CA17, CA51, CA39) of the skin bacterium previously recovered from patients with acne. In particular, we were interested in detecting novel genetic determinants associated with resistance to fluoroquinolone and macrolide antibiotics that could then be confirmed experimentally.

Methods: A range of open source bioinformatics tools were used to 'mine' genetic determinants of antimicrobial resistance and plasmid borne contigs, and to characterise the phylogenetic diversity of the MDR strains.

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Background: Healthcare workers (HWs) have at least twice the risk of tuberculosis (TB) compared to the general population. There is growing emphasis on latent TB infection (LTBI) in high-risk populations. Yet we know little about HWs' perspectives of LTBI testing and treatment to inform implementation in high-incidence settings.

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A growing body of evidence supports an important role for alterations in the brain-gut-microbiome axis in the aetiology of depression and other psychiatric disorders. The potential role of the oral microbiome in mental health has received little attention, even though it is one of the most diverse microbiomes in the body and oral dysbiosis has been linked to systemic diseases with an underlying inflammatory aetiology. This study examines the structure and composition of the salivary microbiome for the first time in young adults who met the DSM-IV criteria for depression (n = 40) and matched controls (n = 43) using 16S rRNA gene-based next generation sequencing.

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Article Synopsis
  • A considerable number of pediatric tuberculosis (TB) cases go unreported due to difficulty in diagnosis, with the experiences of affected children and their families remaining largely overlooked.
  • The study, conducted in four Indian cities, involved interviews with families of 100 children diagnosed with TB, focusing on their experiences during the diagnosis and treatment process.
  • Results indicated significant delays in patient diagnosis, with families facing numerous challenges, including stigma and disruption to daily life, highlighting the urgent need for more effective TB care pathways for children.
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The anaerobic bacterium has been increasingly linked to the development of degenerative disc disease (DDD), although causality is yet to be conclusively proven. To better study how this organism could contribute to the aetiology of DDD, improved animal models that are more reflective of human disc anatomy, biology and mechanical properties are required. Against this background, our proof-of concept study aimed to be the first demonstration that could be safely administered percutaneously into sheep intervertebral discs (IVDs) for in vivo study.

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Sarcoidosis may have more than a single causative agent, including infectious and non-infectious agents. Among the potential infectious causes of sarcoidosis, and are the most likely microorganisms. Potential latent infection by both microorganisms complicates the findings of molecular and immunologic studies.

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Previously, we proposed the hypothesis that similarities in the inflammatory response observed in acne vulgaris and degenerative disc disease (DDD), especially the central role of interleukin (IL)-1β, may be further evidence of the role of the anaerobic bacterium (previously ) in the underlying aetiology of disc degeneration. To investigate this, we examined the upregulation of IL-1β, and other known IL-1β-induced inflammatory markers and neurotrophic factors, from nucleus-pulposus-derived disc cells infected in vitro with for up to 48 h. Upon infection, significant upregulation of IL-1β, alongside IL-6, IL-8, chemokine (C-C motif) ligand 3 (CCL3), chemokine (C-C motif) ligand 4 (CCL4), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), was observed with cells isolated from the degenerative discs of eight patients versus non-infected controls.

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The discovery of T-cell responses to SARS-CoV-2 in non-infected individuals indicates cross-reactive immune memory from prior exposure to human coronaviruses (HCoV) that cause the common cold. This raises the possibility that "immunity" could exist within populations at rates that may be higher than serology studies estimate. Besides specialized research labs, however, there is limited ability to measure HCoV CD4+ and CD8+ T-cell responses to SARS-CoV-2 infection, which currently impedes interpretation of any potential correlation between COVID-19 disease pathogenesis and the calibration of pandemic control measures.

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Subclinical infection associated with orthopedic devices can be challenging to diagnose. The goal of this study was to evaluate longitudinal, microcomputed tomography (microCT) imaging in a rat model of subclinical orthopedic device-related infection caused by Staphylococcus epidermidis and four different Cutibacterium (previously Propionibacterium) acnes strains, and compare outcomes with non-inoculated and historical S. aureus-inoculated controls.

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(previously ) is an anaerobic, Gram-positive commensal of the human body. The bacterium has been associated with a variety of diseases, including acne vulgaris, prosthetic joint infections, prostate cancer, and sarcoidosis. The accumulation of in diseases such as acne and prostate cancer has been shown to correlate with enhanced inflammation.

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Porphyrins are intermediate metabolites in the biosynthesis of vital molecules, including heme, cobalamin, and chlorophyll. Bacterial porphyrins are known to be proinflammatory, with high levels linked to inflammatory skin diseases. species are dominant skin commensals and play essential roles in defending against pathogens and in triggering an inflammatory response.

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This paper outlines insights qualitative research brings to the study of quality of care. It advocates understanding care as sequential, interpersonal action aimed at improving health and documenting the networks in which care occurs. It assesses the strengths and weakness of contemporary quantitative and qualitative approaches to examining quality of care for tuberculosis (TB) before outlining three qualitative research programs aimed at understanding quality of TB in India.

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Quantum sensors based on nitrogen-vacancy centers in diamond have emerged as a promising detection modality for nuclear magnetic resonance (NMR) spectroscopy owing to their micrometer-scale detection volume and noninductive-based detection. A remaining challenge is to realize sufficiently high spectral resolution and concentration sensitivity for multidimensional NMR analysis of picoliter sample volumes. Here, we address this challenge by spatially separating the polarization and detection phases of the experiment in a microfluidic platform.

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Purpose: Recent research shows an increasing recognition that organisms not traditionally considered infectious in nature contribute to disease processes. Propionibacterium acnes (P. acnes) is a gram-positive, aerotolerant anaerobe prevalent in the sebaceous gland-rich areas of the human skin.

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The anaerobic bacterium is believed to play an important role in the pathophysiology of the common skin disease acne vulgaris. Over the last 10 years our understanding of the taxonomic and intraspecies diversity of this bacterium has increased tremendously, and with it the realisation that particular strains are associated with skin health while others appear related to disease. This extensive review will cover our current knowledge regarding the association of phylogroups, clonal complexes and sequence types with acne vulgaris based on multilocus sequence typing of isolates, and direct ribotyping of the strain population in skin microbiome samples based on 16S rDNA metagenomic data.

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In 2016, division of the genus Propionibacterium into four distinct genera was proposed. As a consequence, the species Propionibacterium acnes was transferred to Cutibacterium gen. nov.

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Propionibacterium acnes, a non-spore-forming anaerobic Gram-positive bacterium, has been linked to a wide range of opportunistic human infections and conditions, most notably acne vulgaris. Here, we present the draft genome sequence of P. acnes subsp.

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Purpose: The presence of Propionibacterium acnes in a substantial component of resected disc specimens obtained from patients undergoing discectomy or microdiscectomy has led to the suggestion that this prominent human skin and oral commensal may exacerbate the pathology of degenerative disc disease. This hypothesis, therefore, raises the exciting possibility that antibiotics could play an important role in treating this debilitating condition. To date, however, little information about antibiotic penetration into the intervertebral disc is available.

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