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21.
Rosaria Cozzolino Laura De Magistris Paola Saggese Matteo Stocchero Antonella Martignetti Michele Di Stasio Antonio Malorni Rosa Marotta Floriana Boscaino Livia Malorni 《Analytical and bioanalytical chemistry》2014,406(19):4649-4662
Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders which have a severe life-long effect on behavior and social functioning, and which are associated with metabolic abnormalities. Their diagnosis is on the basis of behavioral and developmental signs usually detected before three years of age, and there is no reliable biological marker. The objective of this study was to establish the volatile urinary metabolomic profiles of 24 autistic children and 21 healthy children (control group) to investigate volatile organic compounds (VOCs) as potential biomarkers for ASDs. Solid-phase microextraction (SPME) using DVB/CAR/PDMS sorbent coupled with gas chromatography–mass spectrometry was used to obtain the metabolomic information patterns. Urine samples were analyzed under both acid and alkaline pH, to profile a range of urinary components with different physicochemical properties. Multivariate statistics techniques were applied to bioanalytical data to visualize clusters of cases and to detect the VOCs able to differentiate autistic patients from healthy children. In particular, orthogonal projections to latent structures discriminant analysis (OPLS-DA) achieved very good separation between autistic and control groups under both acidic and alkaline pH, identifying discriminating metabolites. Among these, 3-methyl-cyclopentanone, 3-methyl-butanal, 2-methyl-butanal, and hexane under acid conditions, and 2-methyl-pyrazine, 2,3-dimethyl-pyrazine, and isoxazolo under alkaline pH had statistically higher levels in urine samples from autistic children than from the control group. Further investigation with a higher number of patients should be performed to outline the metabolic origins of these variables, define a possible association with ASDs, and verify the usefulness of these variables for early-stage diagnosis. Figure
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Emanuela Colombo Rosaria Pascente Daniela Triolo Claudia Bassani Anthea De Angelis Francesca Ruffini Linda Ottoboni Giancarlo Comi Gianvito Martino Cinthia Farina 《Molecules (Basel, Switzerland)》2020,25(22)
Astrocytes greatly participate to inflammatory and neurotoxic reactions occurring in neurodegenerative diseases and are valuable pharmacological targets to support neuroprotection. Here we used human astrocytes generated from reprogrammed fibroblasts as a cellular model to study the effect of the compound Laquinimod and its active metabolite de-Laquinimod on astrocyte functions and the astrocyte–neuron interaction. We show that human iAstrocytes expressed the receptor for the inflammatory mediator IL1 and responded to it via nuclear translocation of NFκB, an event that did not occur if cells were treated with Laquinimod, indicating a direct anti-inflammatory activity of the drug on the human astrocyte. Similarly, while exposure to IL1 downregulated glial glutamate transporters GLAST and GLT1, treatment with Laquinimod supported maintenance of physiological levels of these proteins despite the inflammatory milieu. Laquinimod also induced nuclear translocation of the aryl hydrocarbon receptor (AHR), suggesting that drug action was mediated by activation of the AHR pathway. However, the drug was effective despite AHR inhibition via CH223191, indicating that AHR signaling in the astrocyte is dispensable for drug responses. Finally, in vitro experiments with rat spinal neurons showed that laquinimod did not exert neuroprotection directly on the neuron but dampened astrocyte-induced neurodegeneration. Our findings indicate that fibroblast-derived human astrocytes represent a suitable model to study astrocyte–neuron crosstalk and demonstrate indirect, partial neuroprotective efficacy for laquinimod. 相似文献
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Marina Sicignano Dr. Rosaria Schettini Luisa Sica Giovanni Pierri Prof. Dr. Francesco De Riccardis Prof. Dr. Irene Izzo Dr. Bholanath Maity Dr. Yury Minenkov Prof. Dr. Luigi Cavallo Dr. Giorgio Della Sala 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(29):7131-7141
The first highly enantioselective arylogous Michael reaction (AMR) of 3-unsubstituted phthalides has been described. This phase-transfer methodology, which uses catalytic amounts of KOH/18-crown-6 catalyst in mesitylene in the presence of N,O-bis(trimethylsilyl)acetamide (BSA), gives access to a broad range of 3-monosubstituted phthalides with high levels of syn diastereoselectivity and good yields, starting from 3-unsubstituted derivatives and diverse α,β-unsaturated carbonyl compounds. The reaction also applies to unactivated 3-alkyl phthalides to afford 3,3-dialkyl derivatives. A plausible mechanism has been suggested. DFT analysis of possible transition states gives a rationale of the high syn diastereoselectivity observed and its correlation with the solvent's dielectric constant. 相似文献
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De Napoli M Nardis S Paolesse R Vicente MG Lauceri R Purrello R 《Journal of the American Chemical Society》2004,126(19):5934-5935
In aqueous solution meso-tetrakis(4-phosphonatophenyl)porphyrin shows self-aggregation processes controlled by the "sergeant-soldier rule". After partial protonation of the external phosphonic groups, it is possible (i) to further protonate the inner nitrogen atoms of the molecules or (ii) to allow, over time, the system to aggregate. Therefore, the two procedure lead to a different system evolution, producing species with different chemico-physical properties. 相似文献
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Vincenzo Cunsolo Elisa Cairone Rosaria Saletti Vera Muccilli Salvatore Foti 《Rapid communications in mass spectrometry : RCM》2009,23(13):1907-1916
Two coeluting components, with experimentally measured Mr values of 25529 and 24606 Da, were identified by reversed‐phase high‐performance liquid chromatography (RP‐HPLC) and mass spectrometric analysis in the dephosphorylated casein fraction of a milk sample collected from an individual donkey belonging to the Ragusano breed of the east of Sicily. By coupling enzymatic digestions, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) and RP‐HPLC/nano‐electrospray ionization tandem mass spectrometry (nESI‐MS/MS) analysis, the two proteins were identified as donkey β‐CNs and their sequences characterized completely, using the two known β‐CNs from mare as references. The two donkey β‐CNs, showing a mass difference of 923 Da, differ by the presence of the domain E27SITHINK34 in the full‐length component (Mr 25529 Da). In comparison with the mare's β‐CNs used as reference, they present nine amino acid substitutions: L→S37, R→H52, S→N81, P→V84, L→V91, R→Q203, P→L/I206, L→F210 and A→P219. Together, these substitutions account for the increase of 18 Da in the Mr of the donkey β‐CNs with respect to the counterparts from the mare. The molecular mass determination by ESI‐MS for the phosphorylated proteins showed that the full‐length component was composed of highly multi‐phosphorylated isoforms with five to seven phosphate groups. By analogy with the homologous mare's β‐CNs, the full‐length (226 amino acids) β‐CN was termed variant A, whereas the shorter (218 amino acids) β‐CN was termed variant AΔ5. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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In this paper the complementary hyperstructure obtained from a multiplicative hyperring is considered. Furthermore a characterization for such hyperstructures obtained starting from a strongly distributive multiplicative hyperring is given. 相似文献
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A combination of more stable counter-cation (tetraphenylphosphonium in place of tetrapropylammonium), of local basic microenvironment, and of a non-solubilizing reaction medium (supercritical CO2) improves the life-cycle and reusability of catalytic ORMOSILs doped with perruthenate in the oxidation of alcohols with O2. A number of different bases were co-entrapped and their effect on catalysis assessed in the oxidative dehydrogenation of benzyl alcohol in dense phase carbon dioxide at 22 MPa and 75 °C. The optimized catalyst retains most of its activity after five consecutive runs when a normal ORMOSIL-entrapped TPAP has become inactive. Deactivation of TPAP could be ascribed by EPR analysis to the formation of catalytically inactive RuO2. 相似文献