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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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Inside Back Cover: Self‐Assembly of a 3d–5f Trinuclear Single‐Molecule Magnet from a Pentavalent Uranyl Complex (Angew. Chem. Int. Ed. 49/2014) 下载免费PDF全文
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Gallo P Nasi A Vinci F Guadagnuolo G Brambilla G Fiori M Serpe L 《Rapid communications in mass spectrometry : RCM》2005,19(4):574-579
In this work we present a method for confirmatory analysis of chloramphenicol (CAP) in bovine and buffalo raw milk. CAP is extracted in acetonitrile and purified by affinity chromatography on an alpha-1-acid glycoprotein (AAG) column, then is identified and determined by ion-trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) analysis in the negative ion mode. CAP was identified at the minimum required performance limit (MRPL) of 0.30 ppb, by monitoring the [M-H]- ion and at least two product ions, meeting the qualitative and quantitative criteria set by the European Commission in Decision 2002/657/EC for confirmation of prohibited veterinary drugs. The trueness and within-day and between-day repeatability data are also reported. Moreover, the loading capacity of affinity columns towards CAP was tested. This method, based on the molecular recognition between drug and AAG during the purification step to improve sample cleanup, represents a quantitative and repeatable procedure for confirmatory analysis, and fits the requirements for the routine official control of CAP residues in raw milk. 相似文献
5.
Sedat Ture Rafig Gurbanov Murat Tuna 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):600-610
AbstractThe reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6 (1) with 2-mercaptoethanol, 2-HS-CH2-CH2-OH (2), in (1:1, 1:2 and 1:3) mole ratios, in excess of NaH, in THF and diethylether solutions yield a total of 6 novel products: one mono spiro, N3P3Cl4[O-CH2-CH2-S] (3); one mono-substituted open chain, N3P3Cl5[S-CH2-CH2-OH] (4); one dispiro, N3P3Cl2[O-CH2-CH2-S]2 (5); one tri-substituted open chain, N3P3Cl3[S-CH2-CH2-OH]3 (6); one tris-spiro, N3P3[O-CH2-CH2-S]3 (7) and one disubstituted open chain, N3P3Cl4[S-CH2-CH2-OH]2 (8) derivatives. The spiro products (3, 5 and 7) are formed as the major products in this system and all of the synthesized compounds are found to be stable at room temperature. The structures of the derived compounds were elucidated by elemental analysis, TLC-MS, 31P and 1H NMR spectral data. For evaluation of melting behavior of derivatives (6) and (7), thermal transition peaks and their corresponding enthalpies were determined via DSC technique. 相似文献
6.
Conrad A. P. Goodwin Dr. Floriana Tuna Prof. Eric J. L. McInnes Prof. Stephen T. Liddle Dr. Jonathan McMaster Dr. Inigo J. Vitorica‐Yrezabal Dr. David P. Mills 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14579-14583
We report the synthesis and characterization of the uranium(III) triamide complex [UIII(N**)3] [ 1 , N**=N(SiMe2tBu)2?]. Surprisingly, complex 1 exhibits a trigonal planar geometry in the solid state, which is unprecedented for three‐coordinate actinide complexes that have exclusively adopted trigonal pyramidal geometries to date. The characterization data for [UIII(N**)3] were compared with the prototypical trigonal pyramidal uranium(III) triamide complex [UIII(N“)3] (N”=N(SiMe3)2?), and taken together with theoretical calculations it was concluded that pyramidalization results in net stabilization for [UIII(N“)3], but this can be overcome with very sterically demanding ligands, such as N**. The planarity of 1 leads to favorable magnetic dynamics, which may be considered in the future design of UIII single‐molecule magnets. 相似文献
7.
Pd nanoparticles as efficient catalysts for Suzuki and Stille coupling reactions of aryl halides in ionic liquids 总被引:2,自引:0,他引:2
Pd-catalyzed Suzuki and Stille cross-couplings of aryl bromides and chlorides were carried out in quaternary ammonium salts as solvents under mild conditions and with the recycling of the catalyst. 相似文献
8.
S. Zeki Y?ld?z Mustafa Küçükislamo?lu Murat Tuna 《Journal of organometallic chemistry》2009,694(26):4152-321
In this study, novel unsymmetrical mono- and di-substituted metal free and metallo phthalocyanines containing peripheral naringeninoxy moieties have been prepared. The naringenin-substituted phthalonitrile was synthesized from 4-nitrophthalonitrile and (±)naringenin in dimethylsulfoxide. Preparation of unsymmetrical mono- and di-substituted phthalocyanines, 2-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatocobalt and 2,9-bis-naringenin-7-O-phthalocyanine was performed at 120-140 °C using the corresponding phthalonitrile in the presence of N,N-dimethylethanolamine (DMAE), ZnCl2, CoCl2 and LiCl, respectively. Synthesized new phthalocyanine compounds have been characterized by elemental analysis and 1H NMR, 13C NMR, FT-IR, MS and UV-vis spectroscopy. These are the first known examples of flavonoid-substituted phthalocyanines. 相似文献
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Jnan P. Naskar Chiranjan Biswas Nirmalya Bandyopadhyay James P. S. Walsh Floriana Tuna Miaoli Zhu 《Journal of Coordination Chemistry》2016,69(15):2329-2341
Reaction of the Schiff base, 1-(4-methylimidazol-5-yl) phenylhydrazonopropane-2-one oxime (LH), with copper(II) perchlorate hexahydrate and copper(II) nitrate trihydrate in a 1 : 1 M proportion in methanol affords [Cu2L2(H2O)(ClO4)](ClO4) (1) and [Cu2L2(H2O)2](NO3)2] (2) in moderate yields. Both 1 and 2 have been characterized by elemental analysis, ESI-MS, FT-IR, UV–vis absorption spectroscopy, EPR, electric conductivity, and magnetic susceptibility measurements. The X-ray crystal structures of 1·CH3COCH3 and 2 have been determined. Both compounds are dinuclear copper(II) complexes, with each copper μ2-bridged by two oxime ligands in a μ2-η1,η2 fashion. Variable temperature magnetic studies on 1 and 2 show that both compounds are dominated by an antiferromagnetic coupling through the oxime bridges. 相似文献