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

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

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

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

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

Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease

Altres ajuts: Redes Temáticas de Investigación Cooperativa (RETICS-INVICTUS RD012/0014 and RD16/0019/0010); Fundació CELLEX Barcelona; the "Severo Ochoa" Programme for Centres of Excellence in R&D (SEV-2015-0522), the Obra Social "la Caixa" Foundation (LlumMedBcn).The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow. Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol. After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [− 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001). The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon. The online version contains supplementary material available at 10.1186/s12883-021-02179-8