19 research outputs found

    Atmospheric Solids Analysis Probe (ASAP) and Atmospheric Pressure Gas Chromatography (APGC) coupled to Quadrupole Time of Flight Mass Spectrometry (QTOF-MS) as alternative techniques to trace aromatic markers of mineral oils in food packaging

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    The aim of this work was to select and identify the best markers of aromatic hydrocarbon mineral oil (MOAH) in food packaging. For this purpose, a series of mineral oils was initially analysed. Polycyclic Aromatic Hydrocarbons (PAHs) and the alkylated isomers of Methylnaphthalene (MNS), Diisopropylnaphtalene (DIPNs), Dibenzothiophenes (DBTS), Methyldibenzothiophene (MDBTs), Dimethyldibenzothiophenes (DMDBTs) and Benzonaphthiophenes (BNTS) were then explored. Their presence was confirmed by direct analysis of several mineral oils by Atmospheric Solids Analysis Probe Quadrupole-Time of Flight Mass Spectrometry (ASAP-QTOF-MS). Atmospheric Pressure Gas Chromatography Quadrupole-Time of Flight Mass Spectrometry (APGC-QTOF-MS) was used to confirm the markers in different samples of oils, recycled PET (rPET), recycled cardboard and packaging of couscous and semolina to confirm the contamination. 27 markers were found in the mineral oil samples, 22 of them in rPET, 8 in recycled board and no MOAH were found in packaging of couscous and semolina

    Migration of mineral oil aromatic hydrocarbons (MOAH) from cardboard containers to dry food and prediction tool

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    This research aimed to study the migration of mineral oil aromatic hydrocarbons (MOAH) from primary carton packages to dry foods, using 16 aromatic hydrocarbons as model substances, covering a wide range of molecular masses and chemical structures. Migration experiments were performed using modified polyphenylene oxide as a food simulant and couscous and polenta as dry foods. The migration tests were carried out to simulate storage at room temperature for long periods and in hot food containers as the worst scenario. Multivariate analysis algorithms were applied to correlate and group the migration of model substances, and a partial least squares regression (PLSR) model was built to predict the worst-case migration. The results showed strong correlations in the migration patterns of the model substances, based on their volatility, food matrix, migration time and temperature. Different behaviour between the migration of the most volatile and the heaviest model substances was observed

    Comparative study of different analytical methods for the determination of sterols in human serum by liquid chromatography coupled to mass spectrometry

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    The determination of sterols in human serum allows the diagnosis of inherited disorders in cholesterol metabolism and the evaluation of cardiovascular disease risk. Ten sterols were included in this work: desmosterol and lanosterol (cholesterol precursors); stigmasterol, cholestanol, campesterol, sitosterol and sitostanol (phystosterols) and 7-α-hydroxy 4-cholesten-3-one, 24-hydroxycholesterol and 27-hydroxycholesterol (oxysterols). Historically, sterols have been analyzed by gas chromatography, which involves laborious and time-consuming derivatization steps. Nowadays, liquid chromatography coupled to mass spectrometry has also been used for the analysis of sterols in serum and mammalian cells and tissues.The aim of this study is to reduce the sample processing time of the determination of sterols in human serum.Two different approaches have been compared: an off-line and on-line system. Both methods need a suitable cartridge for cleaning the sample before its subsequent chromatography analysis. Solid phase extraction (SPE) cartridges were used for off-line sample treatment. Six different retention mechanisms were studied, including nonpolar, polar and ionic interactions. In the on-line system, the sample treatment was conducted with the help of a restricted access material (RAM). This sorbent represent a special class of materials that are able to fractionate a biological sample into protein and analyte fractions, based on molecular weight cut-off. The limits of quantification obtained in the off-line method were between 8 and 274 ng/mL. In the on-line method limits of detection and quantification found ranged between 0.01 ng/mL (7-α-hydroxy-4-cholesten-3-one) and 0.5 μg/mL (sitostanol) and from 0.03 ng/mL and 1.7 μg/mL respectively

    Desarrollo de un método analítico para la determinación de esteroles en suero humano mediante un sistema on-line extracción en fase sólida-cromatografía de líquidos-espectrometría de masas

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    Se ha desarrollado un método analítico para determinar cinco esteroles presentes en suero humano. Los esteroles son biomoléculas marcadoras de enfermedades hereditarias relacionadas con el metabolismo del colesterol como la Hipercolesterolemia Familiar. El sistema realiza el tratamiento de muestra, cromatografía y detección de forma automática, facilitando el procesamiento y análisis de muestras biológicas

    Impact of COVID-19 infection on the outcome of patients with ischemic stroke

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    BACKGROUND AND PURPOSE: We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection. METHODS: A prospective, observational, multicentre cohort study in Catalonia, Spain. Recruitment was consecutive from mid-March to mid-May 2020. Patients had an acute ischemic stroke within 48 hours and a previous modified Rankin Scale (mRS) score of 0 to 3. We collected demographic data, vascular risk factors, prior mRS score, National Institutes of Health Stroke Scale score, rate of reperfusion therapies, logistics, and metrics. Primary end point was functional outcome at 3 months. Favourable outcome was defined depending on the previous mRS score. Secondary outcome was mortality at 3 months. We performed mRS shift and multivariable analyses. RESULTS: We evaluated 701 patients (mean age 72.3±13.3 years, 60.5% men) and 91 (13%) had COVID-19 infection. Median baseline National Institutes of Health Stroke Scale score was higher in patients with COVID-19 compared with patients without COVID-19 (8 [3–18] versus 6 [2–14], P=0.049). Proportion of patients with a favourable functional outcome was 33.7% in the COVID-19 and 47% in the non-COVID-19 group. However, after a multivariable logistic regression analysis, COVID-19 infection did not increase the probability of unfavourable functional outcome. Mortality rate was 39.3% among patients with COVID-19 and 16.1% in the non-COVID-19 group. In the multivariable logistic regression analysis, COVID-19 infection was a risk factor for mortality (hazard ratio, 3.14 [95% CI, 2.10–4.71]; P<0.001). CONCLUSIONS: Patients with ischemic stroke and COVID-19 infection have more severe strokes and a higher mortality than patients with stroke without COVID-19 infection. However, functional outcome is comparable in both groups

    Cerebral microbleeds and stroke risk after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies

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    BACKGROUND: Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke. METHODS: We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602. FINDINGS: Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19-2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20-1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82-3·29) for intracranial haemorrhage and 1·23 (1·08-1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08-6·72] for intracranial haemorrhage vs 1·47 [1·19-1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36-9·05] vs 1·43 [1·07-1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69-15·81] vs 1·86 [1·23-1·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48-84] per 1000 patient-years vs 27 intracranial haemorrhages [17-41] per 1000 patient-years; and for ≥20 cerebral microbleeds, 73 ischaemic strokes [46-108] per 1000 patient-years vs 39 intracranial haemorrhages [21-67] per 1000 patient-years). INTERPRETATION: In patients with recent ischaemic stroke or transient ischaemic attack, cerebral microbleeds are associated with a greater relative hazard (aHR) for subsequent intracranial haemorrhage than for ischaemic stroke, but the absolute risk of ischaemic stroke is higher than that of intracranial haemorrhage, regardless of cerebral microbleed presence, antomical distribution, or burden

    GC-MS identification and GC-FID quantitation of terpenoids in Ononidis spinosae Radix

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    A GC-MS method has been developed for the qualitative analysis of sterol and triterpene (terpenoid) constituents of Ononis spinosa L. (spiny restharrow) root without derivatization. β-Sitosterol, campesterol, stigmasterol, stigmastan-3,5-diene sterol compounds and the triterpene derivatives β-amyrin and α-onocerin were identified. A validated GC-FID quantitative method was developed for measuring β-sitosterol, the main sterol component, in various extracts of this plant, obtained with organic solvents and by supercritical fluid extraction. The extracts were cleaned by saponifying and then the β-sitosterol was quantified in the non-saponifiable fractions by GC-FID with an internal standard. In addition, the relative concentrations of the other terpenoids were also determined. The β-sitosterol content in the non-saponifiable solvent extraction fractions was 0.19-5.5%, that of the supercritical fractions were 4.8-9.2%, depending on the experimental conditions. The hexane and the pilot scale SFE extracts were considered as main sources of terpenoids (71.8%; 93.3%, respectively). © 2008 Vieweg+Teubner | GWV Fachverlage GmbH
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