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Conus-involved patients, showed no significant difference regarding age, sex, concurrent brain lesions, and their partial recovery. Predictive values show that the probability of being diagnosed with anti-MOG is roughly 13 times higher in conus-involved patients (25.93% vs. 1.97%), although this probability was still higher for MS, as it has a much higher incidence.

Despite minor differences, the results were in line with previous studies, confirming the higher rate of conus medullaris involvement among anti-MOG patients. Potential underlying causes are proposed and remain to be investigated in future studies.

Despite minor differences, the results were in line with previous studies, confirming the higher rate of conus medullaris involvement among anti-MOG patients. Potential underlying causes are proposed and remain to be investigated in future studies.Asymmetric-Flow Field-Flow Fractionation is a very powerful technique for measuring the molar mass distribution of polymers with complex microstructures. The analysis of some samples such as self-crosslinkable latexes requires to directly dissolve the polymer dispersion in the eluent (THF) without drying it, and this work studies the effect of the presence of this water in those analysis. Taking a polystyrene latex as model system, it was observed that the measured molar mass and radius of gyration increased as the concentration of water in the sample increased. This was an effect of a decrease in the compatibility between the solvent mixture (THF and water) and the polymer, which formed aggregates, and could be predicted calculating the polymer-solvent interaction parameter. When the study was extended to poly(methyl methacrylate), poly(n-butyl acrylate) and poly(vinyl acetate) the same general trend was observed, however, the impact of the water was less significant as the hydrophilicity of the polymer increased. Most importantly, if the samples with the highest water content were first dissolved in THF and afterwards dried using MgSO4 the measured molar mass and radius of gyration values were the same as for the reference sample (dried in the oven), providing a method to analyze samples that cannot be dried into a film and remove the negative effect of the water at the same time.A modification of magnetic-based solvent-assisted dispersive solid-phase extraction (M-SA-DSPE) has been employed for the determination of the biomarkers cortisol and cortisone in saliva samples. M-SA-DSPE is based on the dispersion of the sorbent material by using a disperser solvent like in dispersive solid phase extraction (SA-DSPE) but a magnetic sorbent is used like in magnetic dispersive solid-phase extraction (M-DSPE). Thus, the magnetic sorbent containing the target analytes is retrieved using an external magnet like in M-DSPE. Finally, the analytes are desorbed into a small volume of organic solvent for the subsequent chromatographic analysis. To this regard, a M-SA-DSPE-based method was developed using a magnetic composite as sorbent, made of CoFe2O4 magnetic nanoparticles embedded into a reversed phase polymer (Strata-XTM-RP), which exhibits affinity to the target analytes. Then, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to measure both analytes in the M-SA-DSPE extract. Under the optimized conditions, good analytical features were obtained limits of detection of 0.029 ng mL-1 for cortisol and 0.018 ng mL-1 for cortisone, repeatability (as RSD) ≤ 10 %, and relative recoveries between 86 and 111 %, showing no significant matrix effects. Finally, the proposed method was applied to the analysis of saliva from different volunteers. This new methodology allows a fast and non-invasive determination of cortisol and cortisone, and it employs small amounts of sample, organic solvent and sorbent. Likewise, the sample treatment is minimum, since any supporting equipment (vortex, centrifuge, ultrasounds, etc.) is required.Aconitum alkaloids are versatile in chemical structures and are well known for their bioactivity and toxicity. Cases of analogs with closely similar structures or positional isomers are widespread in herbs of the Aconitum genus. bpV ic50 It is still challenging to rapidly identify unknown compounds via mass spectrometry, especially positional isomers. Herein, to profile the alkaloids of Aconitum stapfianum that possess bioactivity against intoxication by the lateral root of Aconitum carmichaelii (Fuzi), a strategy was developed by carefully determining the fragmentation pathways of authentic standards. A series of rules was summarized and involved charge site effects, hydrogen bonding effects, competitive channels between charge-remote reactions and charge migration reactions, and fragment patterns exhibiting a “diamond shape”. Accordingly, a total of 124 alkaloids in A. stapfianum were tentatively characterized, including 85 potential new compounds and 24 sets of isomers. On the other hand, to explore the material basis of detoxification, a chemical constituent comparison was made between A. stapfianum and Fuzi, and principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were performed to identify markers that were different between the two . In total, 25 characteristic markers were identified to discriminate between these two herbal medicines, of which 14 compounds were specific for A. stapfianum and most of them were characteristic for a para-substituted benzoic acid ester at C-14.Food analysis is a tremendously broad field that is constantly evolving. New methods have emerged to increase productivity, such as modern miniaturized and robotic analytical techniques. In this paper, a micro-solid-phase extraction system (µ-SPE) for clean-up was combined with a robotic autosampler to yield ready-to-analyze extracts. The system was evaluated for its applicability in routine laboratories. The new, automated, high-throughput µ-SPE clean-up method was applied to acetonitrile extracts and was developed for the analysis of pesticide residues in cereals by gas chromatography-Orbitrap mass spectrometry (GC-Orbitrap-MS). The µ-SPE clean-up efficiency was demonstrated in the removal of matrix-interfering components and in the recovery of pesticides. The sorbent bed mixture consisted of magnesium sulfate, primary-secondary amine, C18, and CarbonX, and effectively retained matrix components without loss of target analytes. Analysis of five types of cereals (barley, oat, rice, rye, and wheat) by GC-Orbitrap-MS showed that the method removed more than 70% of matrix components.