ORCID Profile
0000-0002-0094-5245
Current Organisation
Murdoch University
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Publisher: American Association for Cancer Research (AACR)
Date: 2020
DOI: 10.1158/1055-9965.EPI-20-0271
Abstract: Studies do not show consistent relationships between self-reported intake of sugar and outcome of disease. To overcome the drawbacks of self-reported intake methods, we investigated whether there is an agreement in ranking of in iduals between their self-reported sugar intake and urinary sucrose and fructose. We used data of 198 Dutch adults (106 women) from the DUPLO study. Sugar intake of all foods and drinks consumed over 24-hour period was estimated by collecting duplicate portions (DP) and 24-hour recalls (24hR), telephone (24hRT) and Web-based (24hRW), while sugar excretion was based on 24-hour urine s les. Sugar content of 24hR was calculated using a newly developed sugar database and sugar content of DPs and urine s les was calculated using high-performance liquid chromatography–atomic emission spectrometry and LC/MS-MS, respectively. Measurement error models assessed validity coefficients (VC) and attenuation factors (AF). Coefficients were compared with those of protein biomarker. The VC for the marker, using DP as reference, showed comparability with substantially better ranking of participants (0.72 for women and 0.93 for men), than 24hRT (0.57 and 0.78) or 24hRW (0.70 and 0.78) as reference in the sucrose models. The VC of the sucrose models was within 10% of the protein models, except for the model with 24hRT as reference, among women. The AF started at higher values and increased by a greater factor compared with the VC. Repeated measurements of urinary sucrose and fructose as a marker of daily sucrose intake had a ranking performance comparable to urinary nitrogen as marker of protein intake in free-living Dutch adults. The validation of the sugar biomarker in a free-living population with three different dietary assessment methods and its comparable ranking ability with a good recovery biomarker (i.e., protein biomarker) have important research applications. The biomarker may be used for validating dietary assessment methods, for monitoring compliance in human feeding studies, for monitoring the effect of public health interventions, and as a surrogate for ranking subjects according to sucrose intake when information on sucrose in food composition databases is lacking.
Publisher: Springer Science and Business Media LLC
Date: 21-10-2020
DOI: 10.1038/S41598-020-74863-7
Abstract: Flavan-3-ols are a group of bioactive compounds that have been shown to improve vascular function in intervention studies. They are therefore of great interest for the development of dietary recommendation for the prevention of cardio-vascular diseases. However, there are currently no reliable data from observational studies, as the high variability in the flavan-3-ol content of food makes it difficult to estimate actual intake without nutritional biomarkers. In this study, we investigated cross-sectional associations between biomarker-estimated flavan-3-ol intake and blood pressure and other CVD risk markers, as well as longitudinal associations with CVD risk in 25,618 participants of the European Prospective Investigation into Cancer (EPIC) Norfolk cohort. High flavan-3-ol intake, achievable as part of an habitual diet, was associated with a significantly lower systolic blood pressure (− 1.9 (− 2.7 − 1.1) mmHg in men and − 2.5 (− 3.3 − 1.8) mmHg in women lowest vs highest decile of biomarker), comparable to adherence to a Mediterranean Diet or moderate salt reduction. Subgroup analyses showed that hypertensive participants had stronger inverse association between flavan-3-ol biomarker and systolic blood pressure when compared to normotensive participants. Flavanol intake could therefore have a role in the maintenance of cardiovascular health on a population scale.
Publisher: Elsevier BV
Date: 03-2012
DOI: 10.1016/J.CHROMA.2011.09.026
Abstract: The separation of highly basic solutes is an ongoing challenge, especially in achieving suitable retention and peak shapes for compounds such as ephedrines that have both high pK(a) values (≥ 9.3) and low lipophilicity (log P ≤ 1.74). In this study we investigate the application of HILIC as a potential alternative approach for the fast separation of the ephedrines phenylpropanolamine, cathine, ephedrine, pseudoephedrine and methylephedrine in doping control analysis. Using sub-2 μm bare silica bridged-ethylene hybrid (BEH) HILIC material, we evaluate the effects of organic modifier, buffer pH and concentration and column temperature on the retention and selectivity of these compounds. Highly symmetrical peak shapes for all ephedrines were achieved under HILIC conditions (A(s0.1) ≤ 1.1). We also compare the kinetic performance of the optimised HILIC separation with a previously developed high pH reversed-phase approach. van Deemter curves and kinetic plots for the two approaches are constructed and illustrate the kinetic benefits of HILIC over the reversed-phase approach. Improved mass transfer characteristics and enhanced diffusion with HILIC offers lower C-term coefficients of 1.46 and 5.68 for ephedrine with HILIC and RPLC, respectively.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Springer Science and Business Media LLC
Date: 11-09-2019
DOI: 10.1038/S41598-019-49702-Z
Abstract: Data from dietary intervention studies suggest that intake of (−)-epicatechin mediates beneficial vascular effects in humans. However, population-based investigations are required to evaluate associations between habitual intake and health and these studies rely on accurate estimates of intake, which nutritional biomarkers can provide. Here, we evaluate a series of structurally related (−)-epicatechin metabolites (SREM), particularly (−)-epicatechin-3′-glucuronide, (−)-epicatechin-3′-sulfate and 3′-O-methyl-(−)-epicatechin-5-sulfate (SREM B ), as flavan-3-ol and (−)-epicatechin intake. SREM B in urine proved to be a specific indicator of (−)-epicatechin intake, showing also a strong correlation with the amount of (−)-epicatechin ingested (R 2 : 0.86 (95% CI 0.8l 0.92). The median recovery of (−)-epicatechin as SREM B in 24 h urine was 10% (IQR 7–13%) and we found SREM B in the majority of participants of EPIC Norfolk (83% of 24,341) with a mean concentration of 2.4 ± 3.2 µmol/L. Our results show that SREM B are suitable as biomarker of (−)-epicatechin intake. According to evaluation criteria from IARC and the Institute of Medicine, the results obtained support use of SREM B as a recovery biomarker to estimate actual intake of (−)-epicatechin.
Publisher: Springer Science and Business Media LLC
Date: 30-01-2023
DOI: 10.1038/S41590-022-01380-2
Abstract: The biology driving in idual patient responses to severe acute respiratory syndrome coronavirus 2 infection remains ill understood. Here, we developed a patient-centric framework leveraging detailed longitudinal phenotyping data and covering a year after disease onset, from 215 infected in iduals with differing disease severities. Our analyses revealed distinct ‘systemic recovery’ profiles, with specific progression and resolution of the inflammatory, immune cell, metabolic and clinical responses. In particular, we found a strong inter-patient and intra-patient temporal covariation of innate immune cell numbers, kynurenine metabolites and lipid metabolites, which highlighted candidate immunologic and metabolic pathways influencing the restoration of homeostasis, the risk of death and that of long COVID. Based on these data, we identified a composite signature predictive of systemic recovery, using a joint model on cellular and molecular parameters measured soon after disease onset. New predictions can be generated using the online tool shiny.mrc-bsu.cam.ac.uk/apps/covid-19-systemic-recovery-prediction-app , designed to test our findings prospectively.
Publisher: Frontiers Media SA
Date: 02-06-2023
DOI: 10.3389/FPUBH.2023.1105163
Abstract: Burn injury in children causes prolonged systemic effects on physiology and metabolism leading to increased morbidity and mortality, yet much remains undefined regarding the metabolic trajectory towards specific health outcomes. A multi-platform strategy was implemented to evaluate the long-term immuno-metabolic consequences of burn injury combining metabolite, lipoprotein, and cytokine panels. Plasma s les from 36 children aged 4–8 years were collected 3 years after a burn injury together with 21 s les from non-injured age and sex matched controls. Three different 1 H Nuclear Magnetic Resonance spectroscopic experiments were applied to capture information on plasma low molecular weight metabolites, lipoproteins, and α-1-acid glycoprotein. Burn injury was characterized by underlying signatures of hyperglycaemia, hypermetabolism and inflammation, suggesting disruption of multiple pathways relating to glycolysis, tricarboxylic acid cycle, amino acid metabolism and the urea cycle. In addition, very low-density lipoprotein sub-components were significantly reduced in participants with burn injury whereas small-dense low density lipoprotein particles were significantly elevated in the burn injured patient plasma compared to uninjured controls, potentially indicative of modified cardiometabolic risk after a burn. Weighted-node Metabolite Correlation Network Analysis was restricted to the significantly differential features (q & .05) between the children with and without burn injury and demonstrated a striking disparity in the number of statistical correlations between cytokines, lipoproteins, and small molecular metabolites in the injured groups, with increased correlations between these groups. These findings suggest a ‘metabolic memory’ of burn defined by a signature of interlinked and perturbed immune and metabolic function. Burn injury is associated with a series of adverse metabolic changes that persist chronically and are independent of burn severity and this study demonstrates increased risk of cardiovascular disease in the long-term. These findings highlight a crucial need for improved longer term monitoring of cardiometabolic health in a vulnerable population of children that have undergone burn injury.
Publisher: Cold Spring Harbor Laboratory
Date: 08-05-2023
DOI: 10.1101/2023.05.08.23289637
Abstract: We present compelling evidence for the existence of an extended innate viperin dependent pathway which provides crucial evidence for an adaptive response to viral agents like SARS-CoV-2. We show the in vivo biosynthesis of a family of endogenous cytosine metabolites with potential antiviral activity. Two dimensional Nuclear magnetic resonance (NMR) spectroscopy revealed a characteristic spin-system motif indicating the presence of an extended panel of urinary metabolites during the acute viral replication phase. Mass spectrometry additionally allowed the characterization and quantification of the most abundant serum metabolites showing potential diagnostic value of the compounds for viral infections. In total, we unveiled ten nucleoside (cytosine and uracil based) analogue structures, eight of which were previously unknown in humans. The molecular structures of the nucleoside analogues and their correlation with an array of serum cytokines, including IFN-α2, IFN-γ and IL-10, suggest an association with the viperin enzyme contributing to an endogenous innate immune defence mechanism against viral infection.
Publisher: American Chemical Society (ACS)
Date: 09-05-2016
DOI: 10.1021/ACS.ANALCHEM.6B00038
Abstract: A rapid gradient microbore ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) method has been developed to provide a high-throughput analytical platform for the metabolic phenotyping of urine from large s le cohorts. The rapid microbore metabolic profiling (RAMMP) approach was based on scaling a conventional reversed-phase UPLC-MS method for urinary profiling from 2.1 mm × 100 mm columns to 1 mm × 50 mm columns, increasing the linear velocity of the solvent, and decreasing the gradient time to provide an analysis time of 2.5 min/s le. Comparison showed that conventional UPLC-MS and rapid gradient approaches provided peak capacities of 150 and 50, respectively, with the conventional method detecting approximately 19 000 features compared to the ∼6 000 found using the rapid gradient method. Similar levels of repeatability were seen for both methods. Despite the reduced peak capacity and the reduction in ions detected, the RAMMP method was able to achieve similar levels of group discrimination as conventional UPLC-MS when applied to rat urine s les obtained from investigative studies on the effects of acute 2-bromophenol and chronic acetaminophen administration. When compared to a direct infusion MS method of similar analysis time the RAMMP method provided superior selectivity. The RAMMP approach provides a robust and sensitive method that is well suited to high-throughput metabonomic analysis of complex mixtures such as urine combined with a 5-fold reduction in analysis time compared with the conventional UPLC-MS method.
Publisher: Springer Science and Business Media LLC
Date: 16-10-2023
Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.FOODCHEM.2019.125339
Abstract: Intake of red and processed meat has been suspected to increase colorectal cancer risk potentially via endogenous formation of carcinogenic N-nitroso compounds or increased lipid and protein oxidation. Here we investigated the effect of inulin fortification of a pork sausage on these parameters. For four weeks, healthy Sprague-Dawley rats (n = 30) were fed one of three diets: inulin-fortified pork sausage, control pork sausage or a standard chow diet. Fecal content of apparent total N-nitroso compounds (ATNC), nitrosothiols and nitrosyl iron compounds (FeNO) were analyzed in addition to liver metabolism and oxidation products formed in liver, plasma and diets. Intriguingly, inulin fortification reduced fecal ATNC (p = 0.03) and FeNO (p = 0.04) concentrations. The study revealed that inulin fortification of processed meat could be a strategy to reduce nitroso compounds formed endogenously after consumption.
Publisher: American Chemical Society (ACS)
Date: 05-05-2021
Publisher: American Chemical Society (ACS)
Date: 16-03-2021
Publisher: Informa UK Limited
Date: 22-02-2019
DOI: 10.1080/00498254.2018.1559376
Abstract: 1. The metabolic fate and urinary excretion of 2-bromophenol, a phenolic metabolite of bromobenzene, was investigated in male Sprague-Dawley rats following single intraperitoneal doses at either 0, 100, or 200 mg/kg.2. Urine was collected for seven days and s les analysed using
Publisher: Elsevier BV
Date: 05-2013
DOI: 10.1016/J.CHROMA.2013.03.021
Abstract: The separation and quantification of hydrophilic basic compounds continues to challenge reversed-phase chromatography. Ephedrines are an ex le where the optimal separation of their isomers and related substances is complicated due to both their hydrophilicity and basic nature. Here we study two potential ultra-high pressure liquid chromatography (UHPLC) methods and present the merits and limitations of a high pH reversed-phase and a hydrophilic interaction liquid chromatography (HILIC) approach for the separation and quantification of ephedrines for doping control analysis. The study compares a hybrid silica material used for the HILIC separations with a C18 reversed-phase material produced from the same hybrid silica. While both analytical approaches provide good retention and resolution, HILIC offers benefits in terms of peak shape, s le loading capacity and enhanced sensitivity with electrospray ionisation-mass spectrometry (ESI-MS). HILIC permits favourable kinetic performance owing to the low viscosity mobile phase and hence better mass transfer characteristics. Common problems associated with HILIC including retention shifts and undesirable peak shapes are investigated and overcome using a suitable re-equilibration time and injection solvent. Validation data show both approaches provide good linearity (r>0.995), accuracy (RPLC<7.5% error, HILIC<7.6% error) and precision (RPLC<7.0% RSD, HILIC<10.3% RSD) for all analytes. Matrix effects were shown to have a negligible effect on ionisation variability in each mode, with inter-day retention times also being repeatable (<0.17% RSD). HILIC gave increased sensitivity with ESI-MS, giving a 6-fold increase in signal over the RPLC approach. In this application, we demonstrate the use of UHPLC technology coupled with a hybrid quadrupole time-of-flight (QToF) mass analyser. This approach provides fast scanning medium-resolution accurate mass detection for reliable identification and quantification purposes.
Publisher: American Physiological Society
Date: 09-10-2023
Publisher: American Chemical Society (ACS)
Date: 24-02-2023
Publisher: Future Science Ltd
Date: 04-2015
DOI: 10.4155/BIO.14.300
Abstract: Background: Tenofovir disoproxil fumarate (TDF) is an antiretroviral drug used for the treatment of Human Immunodeficiency Virus and Hepatitis B infections. Results: A metabolite that has previously not been observed in the circulation of humans was detected by LC–MS/MS in early time point plasma s les following administration of TDF to healthy volunteers. The metabolite was identified using a range of LC–MS/MS-based techniques as a monoester of TDF, derived from the partially hydrolyzed bis-ester prodrug. TDF, when spiked into plasma, was observed to degrade first to the putative monoester and subsequently to tenofovir. Conclusion: The presence of this unstable metabolite in some s les has implications for s le collection, handling and storage in studies of tenofovir where serum concentrations are determined.
Publisher: Springer Science and Business Media LLC
Date: 29-07-2022
DOI: 10.1038/S41598-022-16886-W
Abstract: A growing body of evidence supports the concept of a systemic response to non-severe thermal trauma. This provokes an immunosuppressed state that predisposes paediatric patients to poor recovery and increased risk of secondary morbidity. In this study, to understand the long-term systemic effects of non-severe burns in children, targeted mass spectrometry assays for biogenic amines and tryptophan metabolites were performed on plasma collected from child burn patients at least three years post injury and compared to age and sex matched non-burn (healthy) controls. A panel of 12 metabolites, including urea cycle intermediates, aromatic amino acids and quinolinic acid were present in significantly higher concentrations in children with previous burn injury. Correlation analysis of metabolite levels to previously measured cytokine levels indicated the presence of multiple cytokine-metabolite associations in the burn injury participants that were absent from the healthy controls. These data suggest that there is a sustained immunometabolic imprint of non-severe burn trauma, potentially linked to long-term immune changes that may contribute to the poor long-term health outcomes observed in children after burn injury.
Publisher: Elsevier BV
Date: 08-2021
DOI: 10.1016/J.JCHROMB.2021.122803
Abstract: Microsomal cytochrome P450 (CYP450) reductase enzymes play a major role in drug and xenobiotic metabolism. Mice which are deficient in hepatic CYP450 reductase serve as excellent models in understanding CYP450 drug metabolism and alterations in the underlying biology and function of these enzymes. A reversed-phase nano-bore UPLC-MS-based proteomic analysis, using an untargeted data independent approach (DIA), has been utilized for liver tissue extracts to evaluate differences between the proteomes of C57Bl6 wild type (WT) and hepatic P450 reductase mice (HRN™). Statistically curated, differentially expressed protein groups highlighted a variety of molecular and biological functions, including binding and catalytic related activities. Thus, elevations were seen for a number of CYP450 enzymes (Cyp2a5 Cyp2b10 Cyp2b19 Cyp2d26 Cyp2a5, Cyp2e1) in the liver extracts of HRN animals. In addition, the major urinary protein 2 (Mup2) was found to be present only in the livers of the HRN group, whilst enoyl-CoA hydratase domain-containing protein 2 (Echdc2) was similarly unique to the the WT livers. Pathway enrichment analysis of the WT liver data indicated perturbations of lipid and energy related pathways, which included bile acid biosynthesis, fatty acid omega oxidation and tricarboxylic acid (TCA) cycle as ex les.
Publisher: Springer Science and Business Media LLC
Date: 30-11-2022
DOI: 10.1038/S41467-022-34243-3
Abstract: Described antimicrobial resistance mechanisms enable bacteria to avoid the direct effects of antibiotics and can be monitored by in vitro susceptibility testing and genetic methods. Here we describe a mechanism of sulfamethoxazole resistance that requires a host metabolite for activity. Using a combination of in vitro evolution and metabolic rescue experiments, we identify an energy-coupling factor (ECF) transporter S component gene ( thfT ) that enables Group A Streptococcus to acquire extracellular reduced folate compounds. ThfT likely expands the substrate specificity of an endogenous ECF transporter to acquire reduced folate compounds directly from the host, thereby bypassing the inhibition of folate biosynthesis by sulfamethoxazole. As such, ThfT is a functional equivalent of eukaryotic folate uptake pathways that confers very high levels of resistance to sulfamethoxazole, yet remains undetectable when Group A Streptococcus is grown in the absence of reduced folates. Our study highlights the need to understand how antibiotic susceptibility of pathogens might function during infections to identify additional mechanisms of resistance and reduce ineffective antibiotic use and treatment failures, which in turn further contribute to the spread of antimicrobial resistance genes amongst bacterial pathogens.
Publisher: MDPI AG
Date: 14-07-2022
DOI: 10.3390/SEPARATIONS9070175
Abstract: Micros les are collections usually less than 50 µL, although all devices that we have captured as part of this review do not fit within this definition (as some can perform collections of up to 600 µL) however, they are considered micros les that can be self-administered. These micros les have been introduced in pre-clinical, clinical, and research settings to overcome obstacles in s ling via traditional venepuncture. However, venepuncture remains the s ling gold standard for the metabolic phenotyping of blood. This presents several challenges in metabolic phenotyping workflows: accessibility for in iduals in rural and remote areas (due to the need for trained personnel), the unamenable nature to frequent s ling protocols in longitudinal research (for its invasive nature), and s le collection difficulty in the young and elderly. Furthermore, venous s le stability may be compromised when the temperate conditions necessary for cold-chain transport are beyond control. Alternatively, research utilising micros les extends phenotyping possibilities to inborn errors of metabolism, therapeutic drug monitoring, nutrition, as well as sport and anti-doping. Although the application of micros les in metabolic phenotyping exists, it is still in its infancy, with whole blood being overwhelmingly the primary biofluid collected through the collection method of dried blood spots. Research into the metabolic phenotyping of micros les is limited however, with advances in commercially available micros ling devices, common barriers such as volumetric inaccuracies and the ‘haematocrit effect’ in dried blood spot micros ling can be overcome. In this review, we provide an overview of the common uses and workflows for micros ling in metabolic phenotyping research. We discuss the advancements in technologies, highlighting key considerations and remaining knowledge gaps for the employment of micros les in metabolic phenotyping research. This review supports the translation of research from the ‘bench to the community’.
Publisher: MDPI AG
Date: 18-07-2023
Abstract: An integrative multi-modal metabolic phenotyping model was developed to assess the systemic plasma sequelae of SARS-CoV-2 (rRT-PCR positive) induced COVID-19 disease in patients with different respiratory severity levels. Plasma s les from 306 unvaccinated COVID-19 patients were collected in 2020 and classified into four levels of severity ranging from mild symptoms to severe ventilated cases. These s les were investigated using a combination of quantitative Nuclear Magnetic Resonance (NMR) spectroscopy and Mass Spectrometry (MS) platforms to give broad lipoprotein, lipidomic and amino acid, tryptophan-kynurenine pathway, and biogenic amine pathway coverage. All platforms revealed highly significant differences in metabolite patterns between patients and controls (n = 89) that had been collected prior to the COVID-19 pandemic. The total number of significant metabolites increased with severity with 344 out of the 1034 quantitative variables being common to all severity classes. Metabolic signatures showed a continuum of changes across the respiratory severity levels with the most significant and extensive changes being in the most severely affected patients. Even mildly affected respiratory patients showed multiple highly significant abnormal biochemical signatures reflecting serious metabolic deficiencies of the type observed in Post-acute COVID-19 syndrome patients. The most severe respiratory patients had a high mortality (56.1%) and we found that we could predict mortality in this patient sub-group with high accuracy in some cases up to 61 days prior to death, based on a separate metabolic model, which highlighted a different set of metabolites to those defining the basic disease. Specifically, hexosylceramides (HCER 16:0, HCER 20:0, HCER 24:1, HCER 26:0, HCER 26:1) were markedly elevated in the non-surviving patient group (Cliff’s delta 0.91–0.95) and two phosphoethanolamines (PE.O 18:0/18:1, Cliff’s delta = −0.98 and PE.P 16:0/18:1, Cliff’s delta = −0.93) were markedly lower in the non-survivors. These results indicate that patient morbidity to mortality trajectories is determined relatively soon after infection, opening the opportunity to select more intensive therapeutic interventions to these “high risk” patients in the early disease stages.
Publisher: Elsevier BV
Date: 03-2012
DOI: 10.1016/J.CHROMA.2011.08.077
Abstract: HPLC has been employed to develop a method for the analysis of cosmetic creams, in particular the compounds hydroquinone, phenol and six preservatives have been studied. UV tuning was optimized as a gradient to achieve lower limits of detection compared to those of a previously validated method. In addition the chromatograms were then exported, aligned and visualized in a principal component analysis (PCA) model. The results were the highly efficient separation of the eight studied compounds. All the compounds showed good linear correlation coefficients (≥ 0.9997), the detection limit was found to be in the range of 15-200 ng/mL, a 10-fold improvement for the preservatives on previous methodology and the average recovery was within limits between 83% and 117% with a relative standard deviation (RSD) less than 3.6% (n=6). The PCA plot was constructed from the UV optimized cosmetic s les chromatograms from real s les, real s les that were spiked and quality controls. Quality controls contained the eight compounds and showed complete clustering in the PCA and three spiked s les containing six to seven toxic components clustered in the same quadrant. The method is highly sensitive and its potential use as a method that could be employed in the control of cosmetics, particularly those containing banned or suspected toxic additives, has been demonstrated.
Publisher: Wiley
Date: 07-2010
DOI: 10.1002/DTA.148
Abstract: This study presents a fast multi-analyte screening method specifically developed for the detection of xenobiotics in urine. The proposed method allows the screening of several classes of substance in a single chromatographic method with a run-time of 11 min, inclusive of post-run and reconditioning times. Chromatographic separation is achieved in 7.2 min using a reversed-phase 2.7 µm fused-core particle column, generating a back-pressure not exceeding 400 bar and therefore enabling the use of traditional high performance liquid chromatography (HPLC) instruments. The effectiveness of this approach was evaluated, by liquid-chromatography tandem mass spectrometry (LC-MS/MS) in positive electrospray ionization, using 20 blank urine s les spiked with 45 compounds prohibited in sport: 11 diuretics, 16 glucocorticoids, 9 stimulants, 5 anti-oestrogens, as well as formoterol, carboxy-finasteride (previously prohibited by the World Anti-Doping Agency (WADA) in 2008), gestrinone and tetrahydrogestrinone. Qualitative validation shows the proposed method to be specific with no significant interference. All of the analytes considered in this study were clearly distinguishable in urine, with limits of detection ranging from 5 ng/mL to 350 ng/mL, significantly below the Minimum Required Performance Levels (MRPL) set by WADA for the accredited sports anti-doping laboratories. All compounds of interest were separated, including synthetic and endogenous glucocorticoids with similar retention times and fragmentation patterns.
Publisher: Elsevier BV
Date: 02-2019
DOI: 10.1016/J.JCHROMB.2018.12.028
Abstract: A UPLC-MS/MS assay, employing a reversed-phase separation, has been applied to the analysis of a number of common amino acids and biogenic amines in rat urine. Analytes were derivatised, using 6‑aminoquinolyl‑N‑hydroxysuccinimidyl carbamate (AccQTag Ultra™
Publisher: Cold Spring Harbor Laboratory
Date: 30-07-2023
DOI: 10.1101/2023.07.28.550938
Abstract: Impaired wound healing in burn injuries can lead to complications such as skin graft loss, infection, and increased risk of scarring, which impacts long-term patient outcomes and quality of life. While wound repair in severe burns has received substantial research attention, poor wound outcomes in cases of non- severe burns (classified as % of the total body surface area (TBSA)) remain relatively understudied despite also having considerable physiological impact and constituting the majority of hospital admissions for burns. Predicting outcomes in the early stages of healing would decrease financial and patient burden, and aid in preventing long-term complications from poor wound healing. Lipids have been implicated in inflammation and tissue repair processes and may play essential roles in burn wound healing. Longitudinal plasma s les were collected from patients (n=20) with non-severe ( % TBSA) flame or scald burns over a 6-week period including timepoints pre- and post-surgical intervention. S les were analysed using liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance spectroscopy to detect 850 lipid species and 112 lipoproteins. Statistical analyses, including orthogonal projection to latent structures-discriminant analysis was performed to identify changes associated with either re-epithelialisation or delayed wound re-epithelisation. The results demonstrated that the plasma lipid and lipoprotein profiles at admission could predict wound re-epithelisation outcomes at two weeks post-surgery, and that these discriminatory profiles were maintained over a 6-week period. Triacylglycerides, diacylglycerides (DAG) and low density lipoprotein (LDL) subfractions were associated with delayed wound closure, with DAG(18:2_18:3) and LDL/High density lipoprotein (HDL) ratio having the most influence (p-value 0.02, Cliff’s delta 0.7), while HDL subfractions, phosphatidylinositols, phosphatidylcholines (PC), and phosphatidylserines were associated with re-epithelisation at two weeks post-surgery, with PC(16:0_18:1) and HDL-2 apolipoprotein-A1 showing the greatest influence on the model (p-value 0.01, Cliff’s delta -0.7). We demonstrate clinical prediction of wound re-epithelisation in non-severe burn patients using lipid and lipoprotein profiling. Further validation of the models will potentially lead to personalised intervention strategies to enhance injury outcomes, reducing the risk of chronic complications post-burn injury. Demonstration of wound healing prediction from time of hospital admission for non-severe burns. Plasma lipid and lipoprotein profiles within 48 hours of admission to hospital with non-severe burn injury are distinctly different between patients whose wounds re-epithelialized within two weeks and those with delayed re-epithelisation. Patients with delayed wound re-epithelisation have a persistent lipid and lipoprotein signature from burns admission up to six weeks post-injury.
Publisher: Frontiers Media SA
Date: 06-05-2020
Publisher: Public Library of Science (PLoS)
Date: 15-08-2017
Publisher: Springer Science and Business Media LLC
Date: 08-10-2021
DOI: 10.1007/S00394-020-02392-0
Abstract: It has been suggested that a high intake of sugar or sweeteners may result in an unfavorable microbiota composition however, evidence is lacking. Hence, in this exploratory epidemiological study, we aim to examine if intake of added sugar, sugar-sweetened beverages (SSBs) or artificially sweetened beverages (ASBs) associate with the gut microbiota composition. Participants (18–70 years) in the Malmö Offspring Study have provided blood, urine, and fecal s les and completed both web-based 4 day food records and short food frequency questionnaires. The gut microbiota was assessed by 16S rRNA sequencing, processed in QIIME and matched to Greengenes (v.13.8), giving 64 included genera after filtering. Intake of added sugar ( n = 1371) (also supported by the overnight urinary sugar biomarker in a subgroup n = 577), SSBs ( n = 1086) and ASBs ( n = 1085) were examined as exposures in negative binomial regressions. Various genera nominally associated with intake of added sugar, SSBs, and ASBs. Only the negative association between SSB intake and Lachnobacterium remained significant after multiple testing correction. A positive association between SSB intake and the Firmicutes:Bacteroidetes ratio was also observed. In this wide population, the cross-sectional associations between added sugar and sweet beverage intake and the gut microbiota are modest, but the results suggest that SSB intake is associated negatively with the genus Lachnobacterium and positively with the Firmicutes:Bacteroidetes ratio. Larger studies, preferably using metagenomic sequencing, are needed to further evaluate if a link exists between intake of sugars and sweeteners and the human gut microbiota.
Publisher: Elsevier BV
Date: 02-2021
Publisher: American Chemical Society (ACS)
Date: 07-02-2017
DOI: 10.1021/ACS.ANALCHEM.6B04623
Abstract: A targeted reversed-phase gradient UPLC-MS/MS assay has been developed for the quantification /monitoring of 66 amino acids and amino-containing compounds in human plasma and serum using precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AccQTag Ultra). Derivatization of the target amines required minimal s le preparation and resulted in analytes with excellent chromatographic and mass spectrometric detection properties. The resulting method, which requires only 10 μL of s le, provides the reproducible and robust separation of 66 analytes in 7.5 min, including baseline resolution of isomers such as leucine and isoleucine. The assay has been validated for the quantification of 33 amino compounds (predominantly amino acids) over a concentration range from 2 to 20 and 800 μM. Intra- and interday accuracy of between 0.05 and 15.6 and 0.78-13.7% and precision between 0.91 and 16.9% and 2.12-15.9% were obtained. A further 33 biogenic amines can be monitored in s les for relative changes in concentration rather than quantification. Application of the assay to s les derived from healthy controls and patients suffering from acetaminophen (APAP, paracetamol)-induced acute liver failure (ALF) showed significant differences in the amounts of aromatic and branched chain amino acids between the groups as well as a number of other analytes, including the novel observation of increased concentrations of sarcosine in ALF patients. The properties of the developed assay, including short analysis time, make it suitable for high-throughput targeted UPLC-ESI-MS/MS metabonomic analysis in clinical and epidemiological environments.
Publisher: Elsevier BV
Date: 04-2011
DOI: 10.1016/J.CHROMA.2010.10.104
Abstract: Solvent systems for use with LC-MS often result in a compromise between chromatographic performance and mass spectrometric detection, exemplified here by a LC-MS/MS method development for the analysis of ephedrines in doping control. Ephedrines, frequently found in therapeutic and nutritional preparations, are among the most commonly administered doping agents in competitive sport. Improved separation of these hydrophilic, basic compounds, some of which are diastereoisomers, is achieved in reversed-phase LC by the use of a high pH mobile phase in order to suppress analyte ionisation, and thus alter their polarity, resulting in reduced peak tailing and enhanced retention. However, when coupled to an ESI-MS detector, this eluent composition generated a non-linear and poorly reproducible signal. APCI yielded greater stability and reproducibility and is here presented as an ion source for the analysis of basic compounds under conditions that suppress their ionisation. Errors as large as 49.3% were observed with ESI, compared with 15.4% generated using APCI, for pseudoephedrine over the calibration range (25-400 μg/mL) in urine with a simple dilution and injection of s les. These data highlight the importance of suitable MS conditions for stable performance, necessary for accurate quantification, without undue compromise to the LC separation.
Publisher: Elsevier BV
Date: 11-2022
DOI: 10.1016/J.BURNS.2022.08.021
Abstract: Surgical wound excision is a necessary procedure for burn patients that require the removal of eschar. The extent of excision is currently guided by clinical judgement, with excessinto healthy tissue potentially leading to excessive scar, or inadequate debridement increasing risk of infection. Thus, an objective real-time measure to facilitate accurate excision could support clinical judgement and improve this surgical procedure. This study was designed to investigate the potential use of Rapid evaporative ionisation mass spectrometry (REIMS) as a tool to support data-driven objective tissue excision. Data were acquired using a multi-platform approach that consisted of both Rapid Evaporative Ionisation Mass Spectrometry (REIMS) performed on intact skin, and comprehensive liquid chromatography-mass spectrometry (LC-MS/MS) lipidomics performed on homogenised skin tissue extracts. Data were analysed using principal components analysis (PCA) and multivariate orthogonal projections to latent squares discriminant analysis (OPLS-DA) and logistic regression to determine the predictability of the models. PCA and OPLS-DA models of the REIMS and LC-MS/MS lipidomics data reported separation of excised and healthy tissue. Molecular fingerprints generated from REIMS analysis of healthy skin tissue revealed a high degree of heterogeneity, however, intra-in idual variance was smaller than inter-in idual variance. Both platforms indicated high levels of skin classification accuracy. In addition, OPLS-DA of the LC-MS/MS lipidomic data revealed significant differences in specific lipid classes between healthy control and excised skin s les including lower free fatty acids (FFA), monoacylglycerols (MAG), lysophosphatidylglycerol (LPG) and lysophosphatidylethanolamines (LPE) in excised tissue and higher lactosylceramides (LCER) and cholesterol esters (CE) compared to healthy control tissue. Having established the heterogeneity in the biochemical composition of healthy skin using REIMS and LC-MS/MS, our data show that REIMS has the potential to distinguish between excied and healthy skin tissue s les. This pilot study suggests that REIMS may be an effective tool to support accurate tissue excision during burn surgery.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 24-09-2021
Abstract: A variant in an RNA processing enzyme predisposes to insulin resistance by reducing calcium release and insulin secretion.
Publisher: American Chemical Society (ACS)
Date: 27-08-2020
Publisher: American Chemical Society (ACS)
Date: 19-05-2021
Publisher: Cambridge University Press (CUP)
Date: 27-02-2020
DOI: 10.1017/S0007114520000665
Abstract: Trend analyses based on dietary records suggest decreases in the intakes of total sugar (TS), added and free sugar since 2005 among children and adolescents in Germany. In terms of age trends, TS intake decreased with increasing age. However, self-reported sugar intake in epidemiological studies is criticised, as it may be prone to bias due to selective underreporting. Furthermore, adolescents are more susceptible to underreporting than children. We thus analysed time and age trends in urinary fructose excretion (FE), sucrose excretion (SE) and the sum of both (FE + SE) as biomarkers for sugar intake among 8·5–16·5-year-old adolescents. Urinary sugar excretion was measured by UPLC-MS/MS in 997 24-h urine s les collected from 239 boys and 253 girls participating in the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study cohort between 1990 and 2016. Time and age trends of log-transformed FE, SE and FE + SE were analysed using polynomial mixed-effects regression models. Between 1990 and 2016, FE as well as FE + SE decreased (linear time trend: P = 0·0272 and P 0·0001, respectively). A minor increase in excretion during adolescence was confined to FE (linear age trend: P = 0·0017). The present 24-h excretion measurements support a previously reported dietary record-based decline in sugar intake since 2005. However, the previously seen dietary record-based decrease in TS from childhood to late adolescence was not confirmed by our biomarker analysis, suggesting a constant sugar intake for the period of adolescence.
Publisher: MDPI AG
Date: 03-06-2022
DOI: 10.20944/PREPRINTS202206.0040.V1
Abstract: Micros les (collections usually less than 50 & micro L) have been introduced in pre-clinical, clinical, and research settings to overcome obstacles in s ling via traditional venipuncture. However, venipuncture remains the s ling gold standard for metabolic phenotyping of blood. This pre-sents several challenges in metabolic phenotyping workflows: accessibility for in iduals in ru-ral and remote underserved areas (due to the need for trained personnel), the unamenable nature to frequent s ling protocols in longitudinal research (for its invasive nature), and s le col-lection difficulty in the young and elderly. Furthermore, venous s le stability may be compro-mised when temperate conditions necessary for cold-chain transport are beyond control. Alter-natively, research utilising micros les extends phenotyping possibilities to inborn errors of metabolism, therapeutic drug monitoring, nutrition, as well as sport and anti-doping. Although the application of micros les in metabolic phenotyping exists, it is still in its infancy, with whole blood being overwhelmingly the primary biofluid collected through the collection method of dried blood spots. Research into metabolic phenotyping of micros les is limited however, with advances in commercially available micros ling devices, common barriers such as volumetric inaccuracies and the & lsquo haematocrit effect& rsquo in dried blood spot micros ling can be overcome. In this review, we provide an overview of the common uses and workflows for mi-cros ling in metabolic phenotyping research. We discuss the advancements in technologies, highlighting key considerations and remaining knowledge gaps for employment of micros les in metabolic phenotyping research. Supporting the translation of research from the & lsquo bench to the community& rsquo .
Publisher: Springer Science and Business Media LLC
Date: 16-07-2020
DOI: 10.1038/S41366-020-0595-6
Abstract: Diet has important effects on normal physiology and the potential deleterious effects of high fat diets and obesity on male reproductive health are being increasingly described. We conducted a histological review of the effects of chronic high fat (HF) diet (using a mouse model fed a 45% fat diet for 21 weeks) with a discovery proteomic study to assess for changes in the abundance of proteins in the testis. Mice on a HF diet became obese and developed glucose intolerance. Using mass spectrometry, we identify 102 proteins affected in the testis of obese mice. These included structural proteins important for the blood testis barrier (filamin A, FLNA), proteins involved in oxidative stress responses (spermatogenesis associated 20, SPATA-20) and lipid homoeostasis (sterol regulatory element-binding protein 2, SREBP2 and apolipoprotein A1, APOA1). In addition, an important regulator protein paraspeckle component 1, PSPC-1, which interacts with the androgen receptor was significantly downregulated. Proteomic data was validated using both Western blotting and immunostaining which confirmed and localised protein expression in both mouse and human testis using biopsy specimens. This study focused mainly on the abnormalities that occurred at the protein level and as a result, we have identified several candidate proteins and conducted pathway analysis around the effects of HF diet on the testis providing novel insights not previously described. Some of the identified targets could be targeted therapeutically and future work is directed in this area.
Publisher: MDPI AG
Date: 20-07-2021
Abstract: Improved methods are required for investigating the systemic metabolic effects of SARS-CoV-2 infection and patient stratification for precision treatment. We aimed to develop an effective method using lipid profiles for discriminating between SARS-CoV-2 infection, healthy controls, and non-SARS-CoV-2 respiratory infections. Targeted liquid chromatography–mass spectrometry lipid profiling was performed on discovery (20 SARS-CoV-2-positive 37 healthy controls 22 COVID-19 symptoms but SARS-CoV-2negative) and validation (312 SARS-CoV-2-positive 100 healthy controls) cohorts. Orthogonal projection to latent structure-discriminant analysis (OPLS-DA) and Kruskal–Wallis tests were applied to establish discriminant lipids, significance, and effect size, followed by logistic regression to evaluate classification performance. OPLS-DA reported separation of SARS-CoV-2 infection from healthy controls in the discovery cohort, with an area under the curve (AUC) of 1.000. A refined panel of discriminant features consisted of six lipids from different subclasses (PE, PC, LPC, HCER, CER, and DCER). Logistic regression in the discovery cohort returned a training ROC AUC of 1.000 (sensitivity = 1.000, specificity = 1.000) and a test ROC AUC of 1.000. The validation cohort produced a training ROC AUC of 0.977 (sensitivity = 0.855, specificity = 0.948) and a test ROC AUC of 0.978 (sensitivity = 0.948, specificity = 0.922). The lipid panel was also able to differentiate SARS-CoV-2-positive in iduals from SARS-CoV-2-negative in iduals with COVID-19-like symptoms (specificity = 0.818). Lipid profiling and multivariate modelling revealed a signature offering mechanistic insights into SARS-CoV-2, with strong predictive power, and the potential to facilitate effective diagnosis and clinical management.
Publisher: Wiley
Date: 07-06-2021
DOI: 10.1111/ACEL.13408
Abstract: Changes in the rate and fidelity of mitochondrial protein synthesis impact the metabolic and physiological roles of mitochondria. Here we explored how environmental stress in the form of a high‐fat diet modulates mitochondrial translation and affects lifespan in mutant mice with error‐prone ( Mrps12 ep / ep ) or hyper‐accurate ( Mrps12 ha / ha ) mitochondrial ribosomes. Intriguingly, although both mutations are metabolically beneficial in reducing body weight, decreasing circulating insulin and increasing glucose tolerance during a high‐fat diet, they manifest ergent (either deleterious or beneficial) outcomes in a tissue‐specific manner. In two distinct organs that are commonly affected by the metabolic disease, the heart and the liver, Mrps12 ep / ep mice were protected against heart defects but sensitive towards lipid accumulation in the liver, activating genes involved in steroid and amino acid metabolism. In contrast, enhanced translational accuracy in Mrps12 ha / ha mice protected the liver from a high‐fat diet through activation of liver proliferation programs, but enhanced the development of severe hypertrophic cardiomyopathy and led to reduced lifespan. These findings reflect the complex transcriptional and cell signalling responses that differ between post‐mitotic (heart) and highly proliferative (liver) tissues. We show trade‐offs between the rate and fidelity of mitochondrial protein synthesis dictate tissue‐specific outcomes due to commonly encountered stressful environmental conditions or aging.
Publisher: American Physiological Society
Date: 12-2023
Publisher: Cold Spring Harbor Laboratory
Date: 28-04-2023
DOI: 10.1101/2023.04.24.537960
Abstract: Globally, burns are a significant cause of injury that can cause substantial acute trauma as well as lead to increased incidence of chronic co-morbidity and disease. To date, research has primarily focused on the systemic response to severe injury, with little in the literature reported on impact of non-severe injuries ( % total burn surface area TBSA). To elucidate the metabolic consequences of non-severe burn injury, longitudinal plasma was collected from adults (n=35) who presented at hospital with a non-severe burn injury at admission, and at 6 week follow up. A cross-sectional baseline s le was also collected from non-burn control participants (n=14). S les underwent multiplatform metabolic phenotyping using 1 H nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry to quantify 112 lipoprotein and glycoproteins signatures and 852 lipid species from across 20 subclasses. Multivariate data modelling (Orthogonal projection to latent structures-discriminate analysis) revealed alterations in lipoprotein and lipid metabolism when comparing baseline control to hospital admission s les, with the phenotypic signature found to be sustained at follow up. Univariate (Mann-Whitney U) testing and OPLS-DA indicated specific increases in GlycB (p-value .0e -4 ), low density lipoprotein-2 subfractions (Variable importance in projection score VIP .83e -1 ) and monoacyglyceride (20:4)(p-value .0e -4 ) and decreases in circulating anti-inflammatory high-density lipoprotein-4 subfractions (VIP .75e -1 ), phosphatidylcholines, phosphatidylglycerols, phosphatidylinositols and phosphatidylserines. The results indicate a persistent systemic metabolic phenotype that occurs even in cases of non-severe burn injury. The phenotype is indicative of an acute inflammatory profile which continues to be sustained post-injury, suggesting an impact on systems health beyond the site of injury. The phenotypes contained metabolic signatures consistent with chronic inflammatory states reported to have elevated incidence post-burn injury. Such phenotypic signatures may provide patient stratification opportunities, to identify in idual responses to injury, personalise intervention strategies and improve acute care, reducing risk of chronic co-morbidity.
Publisher: American Chemical Society (ACS)
Date: 17-08-2020
Publisher: Elsevier BV
Date: 07-2020
Publisher: American Chemical Society (ACS)
Date: 03-2022
DOI: 10.1021/ACS.ANALCHEM.1C05389
Abstract: SARS-CoV-2 infection causes a significant reduction in lipoprotein-bound serum phospholipids give rise to supramolecular phospholipid composite (SPC) signals observed in diffusion and relaxation edited
Publisher: American Chemical Society (ACS)
Date: 11-05-2015
DOI: 10.1021/ACS.JPROTEOME.5B00203
Abstract: A new generation of metabolic phenotyping centers are being created to meet the increasing demands of personalized healthcare, and this has resulted in a major requirement for economical, high-throughput metabonomic analysis by liquid chromatography-mass spectrometry (LC-MS). Meeting these new demands represents an emerging bioanalytical problem that must be solved if metabolic phenotyping is to be successfully applied to large clinical and epidemiological s le sets. Ultraperformance (UP)LC-MS-based metabolic phenotyping, based on 2.1 mm i.d. LC columns, enables comprehensive metabolic phenotyping but, when employed for the analysis of thousands of s les, results in high solvent usage. The use of UPLC-MS employing 1 mm i.d. columns for metabolic phenotyping rather than the conventional 2.1 mm i.d. methodology shows that the resulting optimized microbore method provided equivalent or superior performance in terms of peak capacity, sensitivity, and robustness. On average, we also observed, when using the microbore scale separation, an increase in response of 2-3 fold over that obtained with the standard 2.1 mm scale method. When applied to the analysis of human urine, the 1 mm scale method showed no decline in performance over the course of 1000 analyses, illustrating that microbore UPLC-MS represents a viable alternative to conventional 2.1 mm i.d. formats for routine large-scale metabolic profiling studies while also resulting in a 75% reduction in solvent usage. The modest increase in sensitivity provided by this methodology also offers the potential to either reduce s le consumption or increase the number of metabolite features detected with confidence due to the increased signal-to-noise ratios obtained. Implementation of this miniaturized UPLC-MS method of metabolic phenotyping results in clear analytical, economic, and environmental benefits for large-scale metabolic profiling studies with similar or improved analytical performance compared to conventional UPLC-MS.
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Nicola Gray.