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1.
Nutr Neurosci ; 24(8): 614-623, 2021 Aug.
Article in English | MEDLINE | ID: mdl-31479410

ABSTRACT

Background: The aetiology of Attention Deficit Hyperactivity Disorder (ADHD) continues to be debated, although several contributing factors have been acknowledged.Objective: Assess the association between weight, birth attributes, exercise and sleep habits, dietary intake and adherence to a Mediterranean diet, and impulsive behaviour on Spanish ADHD children. Establish whether specific food groups (not just adherence to the Mediterranean diet) associate with impulsive behaviour.Methods: This observational cross-sectional study included 57 ADHD children from Madrid (Spain). Demographic, clinical data, sleep, exercise and technology-use habits were obtained. Anthropometric measurements included height and weight. Adherence to the Mediterranean diet was assessed using the KIDMED test. Barratt Impulsivity Scale version-11c was used to assess impulsivity. Subjects were divided into three groups for analysis, according to their age (6-10 years, children; 11-13 years, pre-adolescents; 14-16 years, adolescents).Results: There were clear associations between those who had higher BIS scores and who slept less at weekends (49.4 ± 10.16 vs. 43.8 ± 12.51), who adhered poorly to the Mediterranean diet (49.9 ± 11.72 vs. 41.6 ± 16.52), who used internet and technological devices for >3 h/day (45.5 ± 13.6 vs. 44.7 ± 12.11), who were born with >2.5 kg (46.1 ± 11.61 vs. 42.9 ± 15.29), who were delivered by caesarean (45.1 ± 12.78 vs. 44.7 ± 12.5) and who were not breastfed (45.0 ± 13.38 vs. 44.8 ± 12.39). Subjects exercising more than 3 days a week also scored slightly higher (45.4±14.02 vs. 44.6±11.85) in the BIS.Conclusion: There is a need to follow up the link between ADHD and sleep onset difficulties, dietary patterns, technological habits, perinatal factors, breastfeeding and birth delivery mode.


Subject(s)
Attention Deficit Disorder with Hyperactivity/epidemiology , Diet , Life Style , Adolescent , Attention Deficit Disorder with Hyperactivity/psychology , Child , Cross-Sectional Studies , Diet, Mediterranean , Female , Humans , Male , Sleep , Spain
2.
Molecules ; 24(9)2019 May 07.
Article in English | MEDLINE | ID: mdl-31067770

ABSTRACT

During the last number of years a variety of crystallization-driven self-assembly (CDSA) processes based on semicrystalline block copolymers have been developed to prepare a number of different nanomorphologies in solution (micelles). We herein present a convenient synthetic methodology combining: (i) The anionic polymerization of 2-vinylpyridine initiated by organolithium functionalized phosphane initiators; (ii) the cationic polymerization of iminophosphoranes initiated by -PR2Cl2; and (iii) a macromolecular nucleophilic substitution step, to prepare the novel block copolymers poly(bistrifluoroethoxy phosphazene)-b-poly(2-vinylpyridine) (PTFEP-b-P2VP), having semicrystalline PTFEP core forming blocks. The self-assembly of these materials in mixtures of THF (tetrahydrofuran) and 2-propanol (selective solvent to P2VP), lead to a variety of cylindrical micelles of different lengths depending on the amount of 2-propanol added. We demonstrated that the crystallization of the PTFEP at the core of the micelles is the main factor controlling the self-assembly processes. The presence of pyridinyl moieties at the corona of the micelles was exploited to stabilize gold nanoparticles (AuNPs).


Subject(s)
Macromolecular Substances/chemistry , Metal Nanoparticles/chemistry , Micelles , Polymers/chemistry , Crystallization , Gold , Macromolecular Substances/chemical synthesis , Organophosphorus Compounds/chemical synthesis , Organophosphorus Compounds/chemistry , Particle Size , Polymerization , Polymers/chemical synthesis , Polyvinyls/chemical synthesis , Polyvinyls/chemistry , Solvents/chemistry
3.
Org Lett ; 20(19): 6033-6036, 2018 10 05.
Article in English | MEDLINE | ID: mdl-30221522

ABSTRACT

A new and highly stereoselective cascade reaction between isocyanoacetate esters and α-hydroxy and α-amino ketones has been developed. A cinchona alkaloid derived aminophosphine/silver(I) catalyst complex promoted the reaction and enabled the ready synthesis of fused bicyclic γ-lactone and γ-lactam oxazolines with high enantiocontrol (up to 99% ee).

4.
Macromol Rapid Commun ; 38(11)2017 Jun.
Article in English | MEDLINE | ID: mdl-28345254

ABSTRACT

The direct chemical functionalization of poly(spirophosphazene) [NP(O2 C12 H8 )]n (1) can be performed by the lithiation of the aromatic rings at low temperature using Schlosser's base (Lit Bu/KOt Bu or "superbase"), and the subsequent reaction with various electrophiles such as ClSiMe3 , ClPPh2 , or MeOB(O2 C6 H12 ) (MeOBpin). The functionalized polymers, isolated in very high yields (>90%) and without degradation of the polymeric chains, have an average degree of substitution per repeat unit ranging from 0.3 (random copolymers) to a maximum of 1.0, which corresponds to the homopolymers [NP(O2 C12 H7 FG)]n (FG (functional group) =SiMe3 , PPh2 , and Bpin). NMR studies, including bidimensional high temperature experiments on silylated and deuterated polymers, show that the substitution is regioselectively occurring at the C3 carbon of the aromatic rings due to the coordination of the lithium cations to the nitrogen of the polyphosphazene chain. The introduction of functional groups on the aromatic rings leads to significant changes in the solubility (silylated polymers), Tg , and electronic properties of the material, showing how the change of substituents in the aromatic rings can lead to polyphosphazenes with properties markedly different from those of the precursor polymer.


Subject(s)
Lithium/chemistry , Organophosphorus Compounds/chemistry , Polymers/chemistry , Magnetic Resonance Spectroscopy , Solubility , Temperature
5.
Chem Commun (Camb) ; 52(70): 10632-5, 2016 Aug 23.
Article in English | MEDLINE | ID: mdl-27500289

ABSTRACT

The highly diastereo- and enantioselective Mannich addition/cyclisation reaction of α-substituted isocyanoacetate ester pronucleophiles and (hetero)aryl and alkyl methyl ketone-derived ketimines using a silver acetate and a cinchona-derived amino phosphine binary catalyst system is reported.

6.
Angew Chem Int Ed Engl ; 55(34): 10102-7, 2016 08 16.
Article in English | MEDLINE | ID: mdl-27455871

ABSTRACT

We herein report the formation of two complex nanostructures, toroidal micelles and bicontinuous nanospheres, by the self-assembly of the single structurally simple crystalline-b-coil diblock copolymer poly[bis(trifluoroethoxy)phosphazene]-b-poly(styrene), PTFEP-b-PS, in one solvent (THF) and without additives. The nature of these nanostructures in solution was confirmed by DLS and cryo-TEM experiments. The two morphologies are related by means of a new type of reversible morphological evolution, bicontinuous-to-toroidal, triggered by changes in the polymer concentration. WAXS experiments showed that the degree of crystallinity of the PTFEP chains located at the core of the toroids was higher than that in the bicontinuous nanospheres, thus indicating that the final morphology of the aggregates is mostly determined by the ordering of the PTFEP core-forming blocks.

7.
Angew Chem Int Ed Engl ; 54(16): 4895-8, 2015 Apr 13.
Article in English | MEDLINE | ID: mdl-25735645

ABSTRACT

A catalytic asymmetric aldol addition/cyclization reaction of unactivated ketones with isocyanoacetate pronucleophiles has been developed. A quinine-derived aminophosphine precatalyst and silver oxide were found to be an effective binary catalyst system and promoted the reaction to afford chiral oxazolines possessing a fully substituted stereocenter with good diastereoselectivities and excellent enantioselectivities.

8.
Chemistry ; 21(5): 1854-9, 2015 Jan 26.
Article in English | MEDLINE | ID: mdl-25418199

ABSTRACT

Regioselective synthesis of dialkoxy 2-cyclopentenones and 2-cyclohexenones with novel substitution patterns has been accomplished by the one-pot combination of three simple starting materials (chromium carbene complex, Weinreb acetamide lithium enolate and 1-alkoxyallenyllithium) under either anhydrous conditions or water-promoted solidification of the reaction mixture. These results revealed an unprecedented water-freezing effect that plays a key role to completely reverse the regioselectivity of the intramolecular carbometalation of an allene moiety.

9.
Chemistry ; 18(23): 7287-95, 2012 Jun 04.
Article in English | MEDLINE | ID: mdl-22511489

ABSTRACT

The successive coupling of an alkoxy(aryl/heteroaryl)carbene complex of chromium with either a ketone or an imide lithium enolate and then a 3-substituted (H, TMS, PhCH(2), PhCH(2)CH(2), Me) propargylic organomagnesium reagent has afforded novel hydroxy-substituted bicyclic [4.3.0]-γ-alkylidene-2-butenolides with three modular points that has allowed the efficient introduction of molecular complexity, including a homopropargylic alcohol core. The selective formation of these five- or six-component heterobicyclisation products is the result of the regioselective integration of the Grignard reagent as a propargyl fragment followed by a cascade CO/alkyne/CO insertion, ketene trapping and elimination sequence. By using lithium enolates of chiral N-acetyl-2-oxazolidinones and the corresponding propargylic organocerium reagents, both enantiomers of these bicyclic heterocycles were efficiently prepared with very high enantiomeric purity. Architecturally, these fused bicyclic butenolides are characterised by a highly unsaturated and oxygenated core and they exhibit strong blue fluorescence in solution.

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