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Dimensionality reduction is an essential step in the processing of analytical chemistry data. When this reduction is carried out by variable selection, it can enable the identification of biochemical pathways. CovSel has been developed to meet this requirement, through a parsimonious selection of non-redundant variables. This article presents the g-CovSel method, which modifies the CovSel algorithm to produce highly complementary groups containing highly correlated variables. This modification requires the theoretical definition of the groups' construction and of the deflation of the data with respect to the selected groups. Two applications, on two extreme case studies, are presented. The first, based on near-infrared spectra related to four chemicals, demonstrates the relevance of the selected groups and the method's ability to handle highly correlated variables. The second, based on genomic data, demonstrates the method's ability to handle very highly multivariate data. Most of the groups formed can be interpreted from a functional point of view, making g-CovSel a tool of choice for biomarker identification in omics. Further work will be carried out to generalize g-CovSel to multi-block and multi-way data.

Under specific conditions, some proteins can self-assemble into fibrillar structures called amyloids. Initially, these proteins were associated with neurodegenerative diseases in eucaryotes. Nevertheless, they have now been identified in the three domains of life. In bacteria, they are involved in diverse biological processes and are usually useful for the cell. For this reason, they are classified as “functional amyloids”. In this work, we focus our analysis on a bacterial functional amyloid called Hfq. Hfq is a pleiotropic regulator that mediates several aspects of genetic expression, mainly via the use of small noncoding RNAs. Our previous work showed that Hfq amyloid-fibrils interact with membranes. This interaction influences Hfq amyloid structure formation and stability, but the specifics of the lipid on the dynamics of this process is unknown. Here, we show, using spectroscopic methods, how lipids specifically drive and modulate Hfq amyloid assembly or, conversely, its disassembly. The reported effects are discussed in light of the consequences for bacterial cell life., SCOPUS: ar.j, info:eu-repo/semantics/published

Xanthines are the most known alkaloids present in coffee plants. The studies about their metabolism and their pharmacological activities have started several years ago to provide more information about the chemical properties of the most popular beverages in the world, such as coffee or tea. This work consisted in performing metabolomic analysis based on LC-(HR)MS data to investigate the metabolism of xanthines in the leaves and in the fruits of Coffea anthonyi, Coffea arabica and Coffea canephora. While C. arabica and C. canephora have been widely studied, only few information is available for C. anthonyi. However, due to the wide climate changes, this species growing at low altitudes could be a promising species to make coffee beverages. The expression of genes for proteins involved in xanthines biosynthesis has also been investigated by performing RT-qPCR. An overview of the histolocalisation of xanthines in the different organs of Coffea arabica flowers was also provided., info:eu-repo/semantics/inPress

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Localization of wireless transmitters is traditionally done using Radio Frequency (RF) sensors that measure the propagation delays between the transmitter and a set of anchor receivers. One of the major challenges of wireless localization systems is the need for anchor nodes to be time-synchronized to achieve accurate localization of a target node. Using a reference transmitter is an efficient way to synchronize the anchor nodes Over-The-Air (OTA), but such algorithms require multiple periodic messages to achieve tight synchronization. In this paper, we propose a new synchronization method that only requires a single message from a reference transmitter. The main idea is to use the Carrier Frequency Offset (CFO) from the reference node, alongside the Time of Arrival (ToA) of the reference node messages, to achieve tight synchronization. The ToA allows the anchor nodes to compensate for their absolute time offset, and the CFO allows the anchor nodes to compensate for their local oscillator drift. Additionally, using the CFO of the messages sent by the reference nodes and the target nodes also allow us to estimate the speed of the targets. The error of the proposed algorithm is derived analytically and is validated through controlled laboratory experiments. Finally, the algorithm is validated by realistic outdoor vehicular measurements with a software-defined radio testbed., SCOPUS: ar.j, info:eu-repo/semantics/published

Manual therapy (MT) is commonly used in rehabilitation to deal with motor impairments in Parkinson’s disease (PD). However, is MT an efficient method to improve gait in PD? To answer the question, a systematic review of clinical controlled trials was conducted. Estimates of effect sizes (reported as standard mean difference (SMD)) with their respective 95% confidence interval (95% CI) were reported for each outcome when sufficient data were available. If data were lacking, p values were reported. The PEDro scale was used for the quality assessment. Three studies were included in the review. MT improved Dynamic Gait Index (SMD = 1.47; 95% CI: 0.62, 2.32; PEDro score: 5/10, moderate level of evidence). MT also improved gait performances in terms of stride length, velocity of arm movements, linear velocities of the shoulder and the hip (p < 0.05; PEDro score: 2/10, limited level of evidence). There was no significant difference between groups after MT for any joint’s range of motion during gait (p > 0.05; PEDro score: 6/10, moderate level of evidence). There is no strong level of evidence supporting the beneficial effect of MT to improve gait in PD. Further randomized controlled trials are needed to understand the impact of MT on gait in PD., SCOPUS: re.j, info:eu-repo/semantics/published

N-glycosylation is one of the most prominent post-translational modifications (PTM) of glycoproteins. Antibodies are glycosylated proteins, and the alteration of this modification may influence its function, stability and half-life. Importantly, antibodies play a central role in humoral immunity against pathogens, particularly immunoglobulin G (IgG), which is a key effector of the humoral immune response.For this reason, the first part of this PhD work was dedicated to the development and validation of a reliable, sensitive and robust analytical method for the characterization of IgG N-glycans. To achieve this aim, procainamide was used for the labeling of the glycans. The analytical method is based on two steps: first an enrichment step using online solid phase extraction (SPE) with hydrophilic interaction liquid chromatography (HILIC) chemistry, then, a separation step using the same chemistry (HILIC) coupled to fluorescence (FLD) and mass spectrometry (MS) detectors Several parameters were optimized using an experimental design. After that, a validation process was performed, and repeatability, precision and stability were confirmed. NIST standard (reference material 8671, monoclonal antibodies), Trixuma© (biosimilar) and MabThera© (bio original) as well as commercial kits, were also used for the validation to compare our findings to the literature.After its validation, we decided to evaluate this method for the characterization of IgG N-glycans in patients with different diseases. Given the pandemic situation, the first studied disease was the COVID-19 with a group of patients suffering from severe COVID-19 and hospitalized in intensive care unit (ICU). Those patients were divided into two groups according to their clinical outcome (survival or death) and compared to healthy volunteers and ICU hospitalized patients suffering from sepsis. Our data indicated that a specific bisecting N-glycan, FA2B, is a potential biomarker of the mortality risk. The increase of F, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

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In recent decades, the study of anion transport across model lipid bilayer membranes has evolved rapidly. Initially focused on chloride transport using simple synthetic transporters, the field has expanded to encompass the investigation of different anions, the development of new monitoring methods for the understanding of the process, and the creation of new transporters. This thesis touches on all these aspects and can be divided in three parts, each dealing with the transport of a different anion.After a general introduction of the concepts of anion transmembrane transport and the use of synthetic transporters, the second chapter of the thesis addresses the transport of phosphate through the lipid membranes of liposomes, a process never reported previously. The work focuses primarily on the development of two methods for monitoring the transport process: the [Eu.pBOH2]+ assay and the 31P NMR assay. The former relies on emission spectroscopy, while the latter utilizes NMR spectroscopy.Each assay came with its own distinct set of challenges. These include the research of a suitable phosphate-sensitive probe and the acquisition of consistent and clear results, in an emission-based assay. Meanwhile, for the NMR-based assay, the primary aim was to enhance sensitivity and optimize the signal-to-noise ratio. We discuss these challenges and the successful implementation of both methods, along with their application in studying phosphate transport mediated by synthetic carriers. Our results conclusively demonstrate the feasibility of phosphate transport and highlight the influence of pH on the process, given by the prevalence of different forms of the anion, namely H2PO4– (the transported form) and HPO42–. Additionally, our exploration of various efficient chloride transporters, found to be poor phosphate transporters, underscores the difficulty of transporting phosphate.Successively, in the third chapter, we focus on fluoride transport, with a primary emphasis on mechani, Doctorat en Sciences de l'ingénieur et technologie, info:eu-repo/semantics/nonPublished

The availability of cannabidiol (CBD) oil products has increased in recent years. No analytical controls are mandatory for these products leading to uncertainties about composition and quality. In this paper, a methodology was developed to identify the oil matrix and to estimate the CBD content in such samples, using mid‐infrared and near‐infrared spectroscopy. Different oils were selected based on the information labeled on products and were bought in food stores in order to create a sample set with a variety of matrices. These oils were spiked with CBD to obtain samples with CBD levels from 0% to 20%. The first part of the study was focused on the qualitative analysis of the oil matrix. A classification model, based on Soft Independent Modeling of Class Analogy, was build using the spiked oils to distinguish between the different oil matrices. For both spectroscopic techniques, the sensitivity, the specificity, the accuracy and the precision were equal to 100%. These models were applied to determine the oil matrix of seized samples. The second part of the study was focused on the quantitative estimation of CBD. After determination of CBD in seized samples using gas chromatography‐tandem mass spectrometry, partial least square regression (PLS‐R) models were built, one for each matrix in the sample set. Both techniques were able to classify unknown oily samples according to their matrix, and although only few samples were available to evaluate the PLS‐R models, the approach clearly showed promising results for the estimation of the CBD content in oil samples., info:eu-repo/semantics/published

More and more countries and organisations emphasise the value of harm reduction measures in the context of illicit drug use and abuse. One of these measures is drug checking, a preventive action that can represent a quick win by tailored consultation on the risks of substance use upon analytical screening of a submitted sample. Unlike drop‐in centres that operate within a fixed setting, enabling drug checking in a harm reduction context at events requires portable, easy to use analytical approaches, operated by personnel with limited knowledge of analytical chemistry. In this case study, four different approaches were compared for the characterisation of 3,4‐methylenedioxymethamphetamine samples and this in the way the approaches would be applied today in an event context. The four approaches are mid‐infrared (MIR), near‐infrared, and Raman spectroscopy, which are today used in drug checking context in Belgium, as well as an electrochemical sensor approach initially developed in the context of law enforcement at ports. The MIR and the electrochemical approach came out best, with the latter allowing for a direct straightforward analysis of the percentage 3,4‐methylenedioxymethamphetamine (as base equivalent) in the samples. However, MIR has the advantage that, in a broader drug checking context, it allows to screen for several molecules and so is able to identify unexpected active components or at least the group to which such components belong. The latter is also an important advantage in the context of the growing emergence of new psychotropic substances., info:eu-repo/semantics/published

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Kashin-Beck disease (KBD) is a multifactorial endemic disease that only occurs in specific Asian areas. Mycotoxin contamination, especially from the Fusarium spp. has been considered as one of the environmental risk factors that could provoke chondrocyte and cartilage damage. This study aimed to investigate whether new mycotoxins could be identified in KBD-endemic regions as a potential KBD risk factor. This was investigated on 292 barley samples collected in Tibet during 2009-2016 and 19 wheat samples collected in Inner Mongolia in 2006, as control, from KBD-endemic and non-endemic areas. The LC-HRMS(/MS) data, obtained by a general mycotoxin extraction technic, were interpreted by both untargeted metabolomics and molecular networks, allowing us to identify a discriminating compound, enniatin B, a mycotoxin produced by some Fusarium spp. The presence of Fusarium spp. DNA was detected in KBD-endemic area barley samples. Further studies are required to investigate the role of this mycotoxin in KBD development in vivo., SCOPUS: ar.j, info:eu-repo/semantics/published

The possible carrier role of Outer Membrane Vesicles (OMVs) for small regulatory noncoding RNAs (sRNAs) has recently been demonstrated. Nevertheless, to perform their function, these sRNAs usually need a protein cofactor called Hfq. In this work we show, by using a combination of infrared and circular dichroism spectroscopies, that Hfq, after interacting with the inner membrane, can be translocated into the periplasm, and then be exported in OMVs, with the possibility to be bound to sRNAs. Moreover, we provide evidence that Hfq interacts with and is inserted into OMV membranes, suggesting a role for this protein in the release of sRNA outside the vesicle. These findings provide clues to the mechanism of host–bacteria interactions which may not be defined solely by protein–protein and protein–outer membrane contacts, but also by the exchange of RNAs, and in particular sRNAs., SCOPUS: ar.j, info:eu-repo/semantics/published

Introduction: Red blood cells (RBC) are one of the key elements of the microcirculation. Their ability to pass through capillaries and to deliver oxygen to cells is due to their large degree of deformability linked to the characteristics of the RBC membrane. Alterations in RBC deformability as a result of membrane damage, linked in part to increased synthesis of reactive oxygen species (ROS), can be observed in several diseases, such as sepsis, and may contribute to the altered microcirculation observed in these pathologies. Hyperbaric oxygen therapy (HBOT), with inhalation of 100 % oxygen, has been proposed in several acute or chronic pathologies, including carbon monoxide poisoning. Objective: We investigated the effects of HBOT on oxidative stress from ROS produced by myeloperoxidase (MPO) and on RBC deformability in patients with acute or chronic inflammation (n = 10), in patients with acute carbon monoxide poisoning (n = 10), and in healthy volunteers (n = 10). Methods: RBC deformability was evaluated before and after HBOT in the various populations using the ektacytometry technique (Laser-assisted Optical Rotational Red Cell Analyzer – LORRCA). Deformability was determined by the elongation index (EI) in relation to the shear stress (SS) over a range of 0.3 to 50 Pa. Oxidative stress was estimated through changes in proteins (chlorotyrosine and homocitrulline) induced by MPO activity measured by liquid chromatography-tandem mass spectrometry analysis. Results: Before HBOT, EI was significantly lower in patients with acute or chronic inflammation than in healthy volunteers and patients with acute carbon monoxide poisoning for the majority of SS values studied. After one session of HBOT, the EI was significantly higher than before HBOT for SS values of 1.93 Pa or higher in patients with acute or chronic inflammation. This effect remains constant after 10 sessions. There were no differences before and after HBOT in protein or amino acid oxidation due to ROS gener, SCOPUS: ar.j, info:eu-repo/semantics/published

Myeloperoxidase (MPO) has been reported in prostate tissue, and considering its pro-oxidant properties, this location might be linked to prostate pathology. The possibility that the glandular prostatic tissue might be the source of MPO and its potential inflammatory effects must be tested. Human prostate material was obtained from prostate biopsies and radical prostatectomies. Immunohistochemistry was performed using MPO-specific human antibody. In situ hybridization using MPO-specific probes and laser-assisted microdissection for quantitative real-time RT-PCR were performed to observe whether MPO is being produced in prostate tissue. Mass spectrometry on prostate biopsies was used to detect products of MPO activity in nucleic acids (DNA/RNA). MPO contribution to intracellular accumulation of ROS and interleukin-8 in prostatic epithelial cells was monitored in vitro. Immunohistochemistry confirmed cellular localization of MPO in epithelial cells of the prostate. The staining varied from light to high intensity. In situ hybridization did not address the presence of mRNA coding for MPO. No MPO-specific modifications on nucleic acids were detected. Mox-LDL was a major factor inducing ROS and cytokines production in prostatic epithelial cells. We did not demonstrate that MPO was synthetized by prostatic epithelial cells. However, in vitro experiments showed the ability of MPO to potentiate the ROS production and inflammation on prostate epithelial cells. Results do not allow us to demonstrate a role of MPO in prostate to date but further studies are mandatory to focus on the potential impact of MPO in the development of prostatic diseases., SCOPUS: ar.j, info:eu-repo/semantics/published

Synthetic molecular receptors can find applications in many areas among which the selective extraction, transport or detection of different species. In this thesis we focused our attention on the study of macrocyclic hexahomotrioxacalix[3]arenes. These receptors possess an 18-membered macrocycle resembling a crown ether (the 18 crown 6 ether) and when they are in their cone conformation, a cavity formed by three aromatic units.In the first part of this thesis, the binding properties of hexahomotrioxacalix[3]arene receptors towards ammonium ions were studied by 1H NMR spectroscopy and in silico methods. Our results showed that these receptors bind primary ammonium ions, including biomolecules, in their polyaromatic cavity even in a competitive environment (CDCl3/CD3OD (4:1)). A binding mode, similar for all guests, was reported with the ammonium head (NH3+) deeply inserted in the polyaromatic cavity of the receptor, enabling the formation of three H-bonds with the ethereal oxygens of the macrocycle. The high complementarity between primary ammonium ions and the receptors results in an unprecedented specificity for primary ammonium ions over secondary, tertiary and quaternary ones. The selective liquid-liquid extraction of primary ammonium salts from water and the selective recognition of lysine-containing peptides was achieved with these receptors. Our results have been reported in the paper “Specific Binding of Primary Ammonium Ions and Lysine-Containing Peptides in Protic Solvents by Hexahomotrioxacalix[3]arenes” Simon Lambert, Kristin Bartik and Ivan Jabin J. Org. Chem. 2020, 85, 10062-10071.In the second part of this thesis, a fluorescent hexahomotrioxacalix[3]arene was developed for the sensing of primary ammonium ions. A pyrene group was grafted on the large rim of an hexahomotrioxacalix[3]arene and its binding properties were studied by 1H NMR spectroscopy, in silico methods and fluorescence spectroscopy. Binding properties similar to those of the non-function, Doctorat en Sciences de l'ingénieur et technologie, info:eu-repo/semantics/nonPublished

Introduction Globisporangium ultimum is an oomycetal pathogen causing damping-off on over 300 different plant hosts. Currently, as for many phytopathogens, its control relies in the use of chemicals with negative impact on health and ecosystems. Therefore, many biocontrol strategies are under investigation to reduce the use of fungicides. Results In this study, the soil bacterium Pseudomonas sp. NCIMB 10586 demonstrates a strong iron-repressed in vitro antagonism against G. ultimum MUCL 38045. This antagonism does not depend on the secretion of the broad-range antibiotic mupirocin or of the siderophore pyoverdine by the bacterial strain. The inhibitor molecule was identified as a novel non-ribosomal peptide synthetase (NRPS) siderophore named mupirochelin. Its putative structure bears similarities to other siderophores and bioactive compounds. The transcription of its gene cluster is affected by the biosynthesis of pyoverdine, the major known siderophore of the strain. Besides mupirochelin, we observed the production of a third and novel NRPS-independent siderophore (NIS), here termed triabactin. The iron-responsive transcriptional repression of the two newly identified siderophore gene clusters corroborates their role as iron scavengers. However, their respective contributions to the strain fitness are dissimilar. Bacterial growth in iron-deprived conditions is greatly supported by pyoverdine production and, to a lesser extent, by triabactin. On the contrary, mupirochelin does not contribute to the strain fitness under the studied conditions. Conclusion Altogether, we have demonstrated here that besides pyoverdine, Pseudomonas sp. NCIMB 10586 produces two newly identified siderophores, namely mupirochelin, a weak siderophore with strong antagonism activity against G. ultimum, and the potent siderophore triabactin., SCOPUS: ar.j, info:eu-repo/semantics/published

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This systematic review documents the protocol characteristics of studies that used neuromuscular electrical stimulation protocols (NMES) on the plantar flexors [through triceps surae (TS) or tibial nerve (TN) stimulation] to stimulate afferent pathways. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement, was registered to PROSPERO (ID: CRD42022345194) and was funded by the Greek General Secretariat for Research and Technology (ERA-NET NEURON JTC 2020). Included were original research articles on healthy adults, with NMES interventions applied on TN or TS or both. Four databases (Cochrane Library, PubMed, Scopus, and Web of Science) were systematically searched, in addition to a manual search using the citations of included studies. Quality assessment was conducted on 32 eligible studies by estimating the risk of bias with the checklist of the Effective Public Health Practice Project Quality Assessment Tool. Eighty-seven protocols were analyzed, with descriptive statistics. Compared to TS, TN stimulation has been reported in a wider range of frequencies (5–100, vs. 20–200 Hz) and normalization methods for the contraction intensity. The pulse duration ranged from 0.2 to 1 ms for both TS and TN protocols. It is concluded that with increasing popularity of NMES protocols in intervention and rehabilitation, future studies may use a wider range of stimulation attributes, to stimulate motor neurons via afferent pathways, but, on the other hand, additional studies may explore new protocols, targeting for more optimal effectiveness. Furthermore, future studies should consider methodological issues, such as stimulation efficacy (e.g. positioning over the motor point) and reporting of level of discomfort during the application of NMES protocols to reduce the inherent variability of the results., SCOPUS: re.j, info:eu-repo/semantics/published

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Lors de cette communication, une analyse fine de l'existant et des besoins au sein du réseau Erasmus+ PULSE a été établie.

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Rapid antigen tests are currently used for population screening of COVID-19. However, they lack sensitivity and utilize antibodies as receptors, which can only function in narrow temperature and pH ranges. Consequently, molecularly imprinted polymer nanoparticles (nanoMIPs) are synthetized with a fast (2 h) and scalable process using merely a tiny SARS-CoV-2 fragment (∼10 amino acids). The nanoMIPs rival the affinity of SARS-CoV-2 antibodies under standard testing conditions and surpass them at elevated temperatures or in acidic media. Therefore, nanoMIP sensors possess clear advantages over antibody-based assays as they can function in various challenging media. A thermal assay is developed with nanoMIPs electrografted onto screen-printed electrodes to accurately quantify SARS-CoV-2 antigens. Heat transfer-based measurements demonstrate superior detection limits compared to commercial rapid antigen tests and most antigen tests from the literature for both the alpha (∼9.9 fg mL–1) and delta (∼6.1 fg mL–1) variants of the spike protein. A prototype assay is developed, which can rapidly (∼15 min) validate clinical patient samples with excellent sensitivity and specificity. The straightforward epitope imprinting method and high robustness of nanoMIPs produce a SARS-CoV-2 sensor with significant commercial potential for population screening, in addition to the possibility of measurements in diagnostically challenging environments., info:eu-repo/semantics/published

Interfaces modified by a molecular monolayer can be challenging to study, particularly in situ, requiring novel approaches. Coupling electrochemical and optical approaches can be useful when signals are correlated. Here we detail a methodology that uses redox electrochemistry to control surface-based fluorescence intensity for detecting DNA hybridization and studying the uniformity of the surface response. A mixed composition single-strand DNA SAM was prepared using potential-assisted thiol exchange with two alkylthiolmodified ssDNAs that were either labeled with a fluorophore (AlexaFluor488) or a methylene blue (MB) redox tag. A significant change in fluorescence was observed when reducing MB to colorless leuco-MB. In situ fluorescence microscopy on a single-crystal gold bead electrode showed that fluorescence intensity depended on (1) the potential controlling the oxidation state of MB, (2) the surface density of DNA, (3) the MB:AlexFluor488 ratio in the DNA SAM, and (4) the local environment around the DNA SAM. MB efficiently quenched AlexaFluor488 fluorescence. Reduction of MB showed a significant increase in fluorescence resulting from a decrease in quenching or energy transfer efficiency. Hybridization of DNA SAMs with its unlabeled complement showed a large increase in fluorescence due to MB reduction for surfaces with sufficient DNA coverage. Comparing electrochemical−fluorescence measurements to electrochemical (SWV) measurements showed an improvement in detection of a small fraction of hybridized DNA SAM for surfaces with optimal DNA SAM composition and coverage. Additionally, this coupled electrochemical redox-fluorescence microscopy method can measure the spatial heterogeneity of electron-transfer kinetics and the influence of the local interfacial environment., SCOPUS: ar.j, info:eu-repo/semantics/published

The treatment of tuberculosis, in particular the multi-drug resistant tuberculosis, remains a challenge mainly because of the therapy duration and the pharmacokinetic variability of the drugs included in the regimen. The monitoring of antituberculosis drugs is a recent tool that could improve the outcome of patients. We developed a LC-MS/MS method allowing the simultaneous quantification of the four first-line drugs (isoniazid, rifampicin, pyrazinamide and ethambutol), a metabolite of isoniazid (acetylisoniazid) and the five main second-line drugs (rifabutin, levofloxacin, moxifloxacin, linezolid and bedaquiline). An isotopologue standard was used for each drug. The protein precipitation was performed with acetonitrile and the separation was carried out using an EC-18 column and a gradient elution. The validated ranges for each drug were adapted to monitor the plasma concentration at 2 h (peak) and 6 h to evaluate their enteric absorption. The intermediate precision (CV) and the trueness at the limit of quantification were ≤ 10.1% and ≤ 10.7%, respectively. Preliminary data were obtained for 12 patients. The results showed that 38% of the patients had infra-therapeutic levels for both rifampicin and isoniazid, that the leading cause of an impaired oral absorption seemed to be malabsorption and that the effective concentrations for rifampicin were in the lower range of the therapeutic interval., SCOPUS: ar.j, info:eu-repo/semantics/published

Near-infrared spectroscopy (NIRS) allows innovative applications in terms of quality control, for example, in raw materials verification, in process analytical technology (PAT), and in discrimination between genuine and falsified medicines. The development of small and cheap handheld devices is expanding in the field, while trying to keep similar performances as benchtop instruments have. Considering traceability and quality control of drug compounds, this work is intended to identify 13 different paracetamol tablets on the Belgian market by using NIRS. The performances of a Fourier-transform near-infrared spectroscopy (FT-NIR) benchtop and two handheld NIR spectrometers were investigated comparatively. All spectra were collected through the blister in the reflectance diffuse mode. NIR spectral fingerprints were pretreated and analyzed using principal component analysis (PCA) and classified with soft independent modeling of class analogy (SIMCA). The performances of the spectrometers were evaluated after standardization of the reference benchtop database to the handheld spectrometers. The instrumental response of the benchtop spectrometer was standardized towards the handheld device using the piecewise direct standardization (PDS) algorithm. These investigations permitted the advantages and limitations of NIR data standardization on predictive models to be pointed out. The SIMCA models based on the spectral data of the benchtop (B), handheld 1 (H1), and handheld 2 (H2) instruments had an accuracy of 99.2%, 97.7%, and 96.2%, respectively. The same accuracy was obtained with the models of the transferred benchtop spectra for the H1 and H2 devices. However, adding handheld spectra to the transferred benchtop spectra resulted in models with improved accuracy: from 97.7% to 98.5% for the H1 instrument and from 96.2% to 97.7% for the H2 instrument. The proposed strategy highlights the potential of using a reference database collected by NIRS for pharmaceutical analyses by, SCOPUS: ar.j, info:eu-repo/semantics/published

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Inflammation and its resolution are the result of the balance between pro-inflammatory and pro-resolving factors, such as specialized pro-resolving mediators (SPMs). This balance is crucial for plaque evolution in atherosclerosis, a chronic inflammatory disease. Myeloperoxidase (MPO) has been related to oxidative stress and atherosclerosis, and MPO-oxidized low-density lipoproteins (Mox-LDLs) have specific characteristics and effects. They participate in foam cell formation and cause specific reactions when interacting with macrophages and endothelial cells. They also increase the production of intracellular reactive oxygen species (ROS) in macrophages and the resulting antioxidant response. Mox-LDLs also drive macrophage polarization. Mox-LDLs are known to be pro-inflammatory particles. However, in the presence of Mox-LDLs, endothelial cells produce resolvin D1 (RvD1), a SPM. SPMs are involved in the resolution of inflammation by stimulating efferocytosis and by reducing the adhesion and recruitment of neutrophils and monocytes. RvD1 also induces the synthesis of other SPMs. In vitro, Mox-LDLs have a dual effect by promoting RvD1 release and inducing a more anti-inflammatory phenotype macrophage, thereby having a mixed effect on inflammation. In this review, we discuss the interrelationship between MPO, Mox-LDLs, and resolvins, highlighting a new perception of the role of Mox-LDLs in atherosclerosis., SCOPUS: re.j, info:eu-repo/semantics/published

The cuticle of C. elegans is impermeable to chemicals, toxins, and pathogens. However, increased permeability is a desirable phenotype because it facilitates chemical uptake. Surface lipids contribute to the permeability barrier. Here, we identify the lipid transfer protein GMAP-1 as a critical element setting the permeability of the C. elegans cuticle. A gmap-1 deletion mutant increases cuticular permeability to sodium azide, levamisole, Hoechst, and DiI. Expressing GMAP-1 in the hypodermis or transiently in the adults is sufficient to rescue this gmap-1 permeability phenotype. GMAP-1 protein is secreted from the hypodermis to the aqueous fluid filling the space between collagen fibers of the cuticle. In vitro, GMAP-1 protein binds phosphatidylserine and phosphatidylcholine while in vivo, GMAP-1 sets the surface lipid composition and organization. Altogether, our results suggest GMAP-1 secreted by hypodermis shuttles lipids to the surface to form the permeability barrier of C. elegans., SCOPUS: ar.j, info:eu-repo/semantics/published

Endoscopic Mucosal Ablation (EMA) is a minimally invasive procedure which eradicates adiseased mucosa to enable regeneration to a healthy state. The procedure is used in clinical practiceto treat a precancerous condition of the esophagus called Barrett’s Esophagus (BE). Anotherpromising indication being studied is the treatment of the mucosa in the first part of the intestine(the duodenum) to improve conditions linked to insulin resistance, including Type 2 Diabetes Mellitus(T2DM) and Non-Alcoholic SteatoHepatitis (NASH). This work aims to propose an alternativetechnique for EMA, in order to improve the treatment of BE and propose a new treatment modalityfor T2DM and NASH. To this end, Cold Atmospheric Plasma (CAP) is considered. CAP is anionized gas containing reactive species which produces a biochemical effect on tissues at ambienttemperature. Over the past two decades plasma treatment has proliferated mainly for the propertiesof its Reactive Oxygen and Nitrogen Species (RONS) on cells. RONS induce an oxidative stressand trigger signaling cascades, resulting in a large range of effects from stimulation (proliferation,regeneration) to cell death, notably by apoptosis, a natural programmed cell death which can reduceinflammation and post-op burden. CAP being a reactive gaseous medium, its diffusion would offera homogeneous, fast, safe, versatile and convenient way of treating large portions of mucosa withminimal complications. In order to assess the potential of CAP EMA, this thesis presents thedesign and optimization of a cold plasma generation, transport and application system followedby an assessment of safety, feasibility and efficacy of the procedure. After establishing the clinical,functional, and safety requirements, a plasma generation and transport system is presented. Itincludes a helium carrier gas ignited by a nanosecond pulsed high voltage generator in a DielectricBarrier Discharge chamber. The latter contains a copper wire to maintain the plasma activ, Doctorat en Sciences de l'ingénieur et technologie, info:eu-repo/semantics/nonPublished

While coffee beans have been studied for many years, researchers are showing a growing interest in coffee leaves and by-products, but little information is currently available on coffee species other than Coffea arabica and Coffea canephora. The aim of this work was to perform a targeted and untargeted metabolomics study on Coffea arabica, Coffea canephora and Coffea anthonyi. The application of the recent high-resolution mass spectrometry-based metabolomics tools allowed us to gain a clear overview of the main differences among the coffee species. The results showed that the leaves and fruits of Coffea anthonyi had a different metabolite profile when compared to the two other species. In Coffea anthonyi, caffeine levels were found in lower concentrations while caffeoylquinic acid and mangiferin-related compounds were found in higher concentrations. A large number of specialized metabolites can be found in Coffea anthonyi tissues, making this species a valid candidate for innovative healthcare products made with coffee extracts., SCOPUS: ar.j, info:eu-repo/semantics/published

Although Erythrina senegalensis is a plant widely used in traditional medicine in sub-Saharan Africa, its biological properties have been poorly investigated to date. We first characterized by conventional reactions the composition of several stem bark extracts and evaluated in acellular and cellular assays their pro-or antioxidant properties supported by their high phenolic and flavonoid content, particularly with the methanolic extract. The pro-or antioxidant effects observed did not correlate with their IC50 concentrations against five cancer cell lines determined by MTT assay. Indeed, the CH2 Cl2 extract and its ethyl acetate (EtOAc) subfraction appeared more potent although they harbored lower pro-or antioxidant effects. Nevertheless, at equipotent concentration, both extracts induced ER-and mitochondria-derived vacuoles observed by fluorescent microscopy that further led to non-apoptotic cell death. LC coupled to high resolution MS investigations have been performed to identify chemical compounds of the extracts. These investigations highlighted the presence of compounds formerly isolated from E. senegalensis including senegalensein that could be retrieved only in the EtOAc subfraction but also thirteen other compounds, such as 16:3-Glc-stigmasterol and hexadecanoic acid, whose anticancer properties have been previously reported. Nineteen other compounds remain to be identified. In conclusion, E. senegalensis appeared rich in compounds with antioxidant and anticancer properties, supporting its use in traditional practice and its status as a species of interest for further investigations in anticancer drug research., SCOPUS: ar.j, info:eu-repo/semantics/published

Spectroscopic techniques such as infrared spectroscopy and Raman spectroscopy are used for a long time in the context of the analysis of illicit drugs, and their use is increasing due to the development of more performant portable devices and easy application in the context of harm reduction through drug checking or onsite forensic analysis. Although these instruments are routinely used with a spectral library, the importance of chemometric techniques to extract relevant information and give a full characterisation of samples, especially in the context of adulteration, is increasing. This review gives an overview of the applications described in the context of the analysis of illicit drug products exploiting the advantages of the combination of spectroscopy with chemometrics. Next to an overview of the literature, the review also tries to emphasize the shortcomings of the presented research papers and to give an incentive to what is needed to include chemometrics as a part of the daily routine of drug checking services and mobile forensic applications., SCOPUS: re.j, info:eu-repo/semantics/published

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Misuse of prescription stimulants (PS) has been reported among students to enhance academic performance in Flanders (Belgium). However, PS misuse among students in the French-speaking community is unknown. The main purpose of the study was to estimate the prevalence of medical use and misuse of PS by university students in the French-speaking community (Belgium), and to investigate the reasons and sources associated with PS misuse., SCOPUS: ar.j, info:eu-repo/semantics/published

Background: In sepsis, neutrophil respiratory bursts participate in endothelium damage, the first step to multiple organ failure. In plasma two antioxidant selenoenzymes, which protect the endothelium, decrease: selenoprotein-P, and to a lesser extent glutathione peroxidase (GPX3). Sodium selenite (Na2SeO3) is a Se donor, but also an oxidant chemotherapy drug depending on its concentration. In a previous published study, Na2SeO3 continuous infusion in septic shock patients at a pharmacological dose of 4 mg1 Se/day on day-1, followed by a high nutritional dose of 1 mg Se/day during 9 days, showed no beneficial effect on weaning of catecholamine nor on survival. In this ancillary study, we report clinical and biological effects of such continuous infusion of Na2SeO3. Methods: This was a multicenter, placebo-controlled, double-blind study on 60 patients. Na2SeO3 or placebo in continuous infusion as described above. Evolution with time of plasma Se, selenoprotein-P, GPX3, Organ dysfunction (sequential organ failure assessment SOFA scores, including PaO2/FiO2, for respiratory failure, and plasma lactate) and quality of life at 6 months (by SF36 scores) were analyzed using two-way (time, treatment) non-parametric repeated-measures analysis of variance (Friedman test). Main Results: At baseline, plasma Se was about a quarter of reference values. From baseline to day-4 plasma Se, selenoprotein-P and GPX3 significantly increased by 3.9, 2.7 and 1.8 respectively in the Na2SeO3 group as compared with placebo and remained elevated by 2.3, 2.7 and 2.1 at day-14 respectively (p < 0.001). Na2SeO3 did not affect global and organ by organ SOFA Scores and plasma lactate concentration at day-1 and later up to day-14. The evolution of PaO2/FiO2 until day-14 was similar in the two groups. Quality of life in the surviving patients at 6 months was similar between the two groups. Conclusion: Continuous infusion of Na2SeO3 at 4 mg Se at day-1 seems to have neither beneficial nor toxic effec, SCOPUS: ar.j, info:eu-repo/semantics/published

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We investigated the effect of bee species identity and harvesting methods on the chemical composition and antiradical activity of 53 honey samples, produced by six stingless bee species in western Kenya (Kakamega forest). Our results illustrate that none of the assayed parameters significantly varied between the honey samples harvested by “punching holes” (n = 25) and “squeezing” (n = 28) methods. By contrast, species identity drove significant differences in the assayed parameters. Positive correlations between the antiradical activity and the phytochemicals (phenols and flavonoids) were observed, and honeys from Liotrigona sp. exhibited the highest amounts of phenols (214 mg GAE/100 g), flavonoids (73.0 mg QE/100 g) and antiradical activity (76.2%). The physicochemical analyses confirm the need to establish separate stingless bee honey standards for moisture, free acidity, invertase, electrical conductivity, and HMF, as these parameters significantly diverged from the set limits for Apis mellifera honey., SCOPUS: ar.j, info:eu-repo/semantics/inPress

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