Antonis Myridakis

• PhD MSc BSc (Hons)
• PostDoc Position at Imperial College London

An instrument integrating thermal desorption (TD) to selected ion flow tube mass spectrometry (SIFT-MS) is presented, and its application to analyze volatile organic compounds (VOCs) in human breath is demonstrated for the first time. The rationale behind this development is the need to analyze breath samples in large-scale multicenter clinical pro...

Urinary volatolomics offers a noninvasive approach for disease detection and monitoring. Herein we present an improved methodology for global volatolomic profiling. Wide coverage was achieved by utilizing a multiphase sorbent for volatile organic compound (VOC) extraction. A single, midpolar column gas chromatography (GC) assay yielded substantiall...

Abstract The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied “explainable” machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult...

Volatolomics offers an opportunity for noninvasive detection and monitoring of human disease. While gas chromatography-mass spectrometry (GC-MS) remains the technique of choice for analyzing volatile organic compounds (VOCs), barriers to wider adoption in clinical practice still exist, including: sample preparation and introduction techniques, VOC...

Objectives: The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased thrombotic and cardiovascular risks. Here we, sought to i) characterize which host variables contribute to fasting serum TMAO levels in real-life settings ii) identify potential actionable therapeutic means related to circulating TMAO. Design: We appl...

The interest around analysis of volatile organic compounds (VOCs) within breath has increased in the last two decades. Uncertainty remains around standardisation of sampling and whether VOCs within room air can influence breath VOC profiles. To assess the abundance of VOCs within room air in common breath sampling locations within a hospital settin...

The regenerative potential of mammalian peripheral nervous system neurons after injury is critically limited by their slow axonal regenerative rate¹. Regenerative ability is influenced by both injury-dependent and injury-independent mechanisms². Among the latter, environmental factors such as exercise and environmental enrichment have been shown to...

Previous microbiome and metabolome analyses exploring non-communicable diseases have paid scant attention to major confounders of study outcomes, such as common, pre-morbid and co-morbid conditions, or polypharmacy. Here, in the context of ischemic heart disease (IHD), we used a study design that recapitulates disease initiation, escalation and res...

Objectives Gut microbiota is a key component in obesity and type 2 diabetes, yet mechanisms and metabolites central to this interaction remain unclear. We examined the human gut microbiome’s functional composition in healthy metabolic state and the most severe states of obesity and type 2 diabetes within the MetaCardis cohort. We focused on the rol...

During the transition from a healthy state to cardiometabolic disease, patients become heavily medicated, which leads to an increasingly aberrant gut microbiome and serum metabolome, and complicates biomarker discovery1,2,3,4,5. Here, through integrated multi-omics analyses of 2,173 European residents from the MetaCardis cohort, we show that the ex...

Early diagnosis of acute mesenteric ischemia (AMI) remains a clinical challenge, and no biomarker has been consistently validated. We aimed to assess the accuracy of three promising circulating biomarkers for diagnosing AMI—citrulline, intestinal fatty acid-binding protein (I-FABP), and d-lactate. A cross-sectional diagnostic study enrolled AMI pat...

Background Autism spectrum disorders (ASD) are associated with dysregulation of the microbiota-gut-brain axis, changes in microbiota composition as well as in the fecal, serum, and urine levels of microbial metabolites. Yet a causal relationship between dysregulation of the microbiota-gut-brain axis and ASD remains to be demonstrated. Here, we hypo...

The analysis of volatile organic compounds (VOCs) within breath for noninvasive disease detection and monitoring is an emergent research field that has the potential to reshape current clinical practice. However, adoption of breath testing has been limited by a lack of standardization. This protocol provides a comprehensive workflow for online and...

This paper comprises an updated version of the 2014 review which reported 1846 volatile organic compounds (VOCs) identified from healthy humans. In total over 900 additional VOCs have been reported since the 2014 review and the VOCs from semen have been added. The numbers of VOCs found in breath and the other bodily fluids are: blood 379, breath 14...

The analysis of urinary volatile organic compounds (VOCs) is a promising field of research with the potential to discover new biomarkers for cancer early detection. This systematic review aims to summarise the published literature concerning cancer-associated urinary VOCs. A systematic online literature search was conducted to identify studies repo...

The regenerative potential of mammalian peripheral nervous system (PNS) neurons after injury is critically limited by their slow axonal regenerative rate ¹ . Since a delayed target re-innervation leads to irreversible loss of function of target organs ² , accelerated axonal regeneration is required to enhance functional outcomes following injury. R...

Tyrosine plays a key role in mammalian biochemistry and defects in its metabolism (e.g., tyrosinemia, alkaptonuria etc.) have significant adverse consequences for those affected if left untreated. In addition, gut bacterially-derived p-cresol and its metabolites are of interest as a result of various effects on host xenobiotic metabolism. A fit-for...

Aims/hypothesisDrug and surgical-based therapies in type 2 diabetes are associated with altered gut microbiota architecture. Here we investigated the role of the gut microbiome in improved glucose homeostasis following bariatric surgery.Methods We carried out gut microbiome analyses in gastrectomised (by vertical sleeve gastrectomy [VSG]) rats of t...

Background Autism Spectrum Disorders (ASD) are associated with dysregulation of the microbiota-gut-brain axis resulting in changes in microbiota composition as well as fecal, serum and urine levels of microbial metabolites. Yet, a causal relationship between dysregulation of the microbiota-gut-brain axis and ASD remains to be demonstrated. Here, we...

Immune cells have unique metabolic requirements to support the energetic and biosynthetic burden during their activation. Delineation of the metabolic tuning of immune cells could lead to novel strategies in treating metabolically-demanding processes including autoimmune diseases. Among innate effectors, monocytes have a distinct role in systemic l...

The human gut is a home for more than 100 trillion bacteria, far more than all other microbial populations resident on the body’s surface. The human gut microbiome is considered as a microbial organ symbiotically operating within the host. It is a collection of different cell lineages that are capable of communicating with each other and the host a...

Objectives: To characterize the impact of PCB exposure on DNA methylation in peripheral blood leucocytes and to evaluate the corresponding changes in relation to possible health effects, with a focus on B-cell lymphoma. Methods: We conducted an epigenome-wide association study on 611 adults free of diagnosed disease, living in Italy and Sweden,...

Few studies have investigated longitudinal associations between early life phthalate exposure and subsequent obesity and cardiovascular risks in children with inconsistent results. We aimed to evaluate the associations between phthalate exposure during gestation and childhood with offspring obesity and cardiometabolic risk factors in 500 mother-chi...

Introduction Smoking cessation during pregnancy is beneficial to both the mother and child. Our objective was to assess if an intensive smoking cessation intervention for pregnant women increases: a) rates of smoking cessation, and b) reduces exposure to tobacco-specific carcinogens during pregnancy. Methods A two-group single-blinded parallel ran...

Correction to: Nature Medicine https://doi.org/10.1038/s41591-018-0061-3, published online 25 June 2018. In the version of this article originally published, the received date was missing. It should have been listed as 2 January 2018. The error has been corrected in the HTML and PDF versions of this article.

Recent prospective studies have shown that dysregulation of the immune system may precede the development of B‐cell lymphomas (BCL) in immunocompetent individuals. However, to date, the studies were restricted to a few immune markers, which were considered separately. Using a nested case–control study within two European prospective cohorts, we mea...

Hepatic steatosis is a multifactorial condition that is often observed in obese patients and is a prelude to non-alcoholic fatty liver disease. Here, we combine shotgun sequencing of fecal metagenomes with molecular phenomics (hepatic transcriptome and plasma and urine metabolomes) in two well-characterized cohorts of morbidly obese women recruited...

Background: The dietary methylamines choline, carnitine, and phosphatidylcholine are used by the gut microbiota to produce a range of metabolites, including trimethylamine (TMA). However, little is known about the use of trimethylamine N-oxide (TMAO) by this consortium of microbes. Results: A feeding study using deuterated TMAO in C57BL6/J mice...

The interaction between high-fat diet (HFD) feeding and the gut microbiome has a strong impact on the onset of insulin resistance (IR) ¹⁻³ . In particular, bacterial lipopolysaccharides (LPS) and dietary fats trigger low-grade inflammation ⁴ through activation of Toll-like receptor 4 (TLR4), a process called metabolic endotoxemia ⁵ . However, littl...

BACKGROUND The dietary methylamines choline, carnitine and phosphatidylcholine are used by the gut microbiota to produce a range of metabolites, including trimethylamine (TMA). However, little is known about the use of trimethylamine N -oxide (TMAO) by this consortium of microbes. RESULTS A feeding study using deuterated TMAO in C57BL6/J mice demo...

Cyflumetofen is a recently introduced acaricide with a novel mode of action, acting as an inhibitor of complex II of mitochondrial electron transport chain. It is activated by hydrolysis and the resulting de-esterified metabolite is a much stronger inhibitor. Cyflumetofen represents a great addition for the control of mite species including Tetrany...

Obesity and type 2 diabetes are associated with low-grade inflammation and specific changes in gut microbiota composition. We previously demonstrated that administration of Akkermansia muciniphila to mice prevents the development of obesity and associated complications. However, the underlying mechanisms of this protective effect remain unclear. Mo...

Temephos is a major organophosphate (OP) larvicide that has been used extensively for the control of Aedes albopictus and Aedes aegypti, the major vectors for viral diseases, such as dengue fever, zika and chikungunya. Resistance to temephos has been recently detected and associated with the upregulation of carboxylesterases (CCEs) through gene amp...

The utility of blood-based omic profiles for linking environmental exposures to their potential health effects was evaluated in 649 individuals, drawn from the general population, in relation to tobacco smoking, an exposure with well-characterised health effects. Using disease connectivity analysis, we found that the combination of smoking-modified...

Phthalate esters (PEs), bisphenol-A (BPA) and parabens (PBs), used in numerous consumer products, are known for their endocrine disrupting properties. Organophosphate chemicals (OPs), the basis of the majority of pesticides, are known for their neurotoxic activity in humans. All these chemicals are associated with health problems to which children...

Exposure to endocrine disruptors, used as additives, preservatives, plasticisers and solvents in numerous consumer products, might cause adverse health effects. Humans exposed to these chemicals, metabolise and excrete them mostly via urine. Urinary metabolite concentrations are used as biomarkers of exposure. We evaluated the exposure of 4-month p...

Cyenopyrafen is a Mitochondrial Electron Transport Inhibitor (METI) acaricide with a novel mode of action at complex II, which has been recently developed for the control of the spider mite Tetranychus urticae, a pest of eminent importance globally. However, some populations of T. urticae are cross-resistant to this molecule, and cyenopyrafen resis...

Phthalates, bisphenol A (BPA) and parabens (PBs), organic chemicals widely used in everyday products, are considered to be endocrine disruptors. We propose a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of seven phthalate metabolites, six PBs and BPA in human urine. All three categories of the above endocri...

Cotton whitefly, Bemisia tabaci (Genn.) (Homoptera: Aleyrodidae) is a major sucking pest in many agricultural and horticultural cropping systems globally. The frequent use of insecticides of different mode of action classes resulted in populations resisting treatments used to keep numbers under economic damage thresholds. Recently it was shown that...

Objectives: Secondhand smoke (SHS) is a defined occupational hazard. The association though between SHS exposure in semi-open air venues and tobacco specific carcinogen uptake is an area of debate. Material and methods: A cross sectional survey of 49 semi-open air cafes in Athens, Greece was performed during the summer of 2008, prior to the adop...

B-cell lymphomas are a diverse group of hematological neoplasms with differential etiology and clinical trajectories. Increased insights in the etiology and the discovery of pre-diagnostic markers have the potential to improve the clinical course of these neoplasms. We investigated in a prospective study global gene expression in peripheral blood m...

Abamectin is one of the most important insecticides worldwide. It is used against major agricultural pests and insects of public health importance, as well as against endoparasites in animal health. Abamectin has been used successfully for the control of the spider mite Tetranychus urticae, a major agricultural pest with global distribution, an ext...

Occupational/ Environmental Lung Disease PostersSESSION TYPE: Original Investigation PosterPRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PMPURPOSE: Secondhand smoke is a well regulated and defined occupational hazard. The association though between occupational SHS exposure in semi-open air venues and tobacco specific carcinogen upt...

A sensitive and selective confirmatory method for milk-residue analysis of ten quinolones and eight cephalosporins by LC-MS/MS has been developed herein. For the chromatographic separation of target analytes, a Perfectsil ODS-2 (250 × 4 mm, 5 μm) analytical column was used and gradient elution was applied, using a mobile phase of 0.1% w/w TFA in wa...

Background: The suitability for omic analysis of biosamples collected in previous decades and currently stored in biobanks is unknown. Objectives: We evaluated the influence of handling and storage conditions of blood-derived biosamples on transcriptomic, epigenomic (CpG methylation), plasma metabolomic [UPLC-ToFMS (ultra performance liquid chromat...