Trastorno por déficit de atención e hiperactividad (TDAH) y consumo de sustancias: datos preliminares de seguimiento en una población de sujetos jóvenes / Attention deficit and hyperactivity disorder (ADHD) and substance use: preliminary outcomes of a follow-up in a young population

Introducción: La relación entre el consumo de sustancias y el trastorno por déficit de atención e hiperactividad (TDAH) se considera cada vez más importante entre adolescentes y jóvenes. Objetivo: Valorar los TDAH que presentan los adolescentes y jóvenes atendidos en el Programa para Adolescentes y Familias de Proyecto Hombre Madrid. Material y métodos: Se han incluido en el estudio los 223 adolescentes y jóvenes (75 % varones) atendidos en el Programa para Adolescentes y Familias de Proyecto Hombre Madrid, desde agosto de 2006 hasta abril de 2009. Para ello se realizó la valoración psiquiátrica de los adolescentes con antecedentes psiquiátricos, en tratamiento con psicofármacos o con sintomatología sugestiva de patología psiquiátrica. Resultados: Del total de la muestra, 15 adolescentes (todos varones) fueron diagnosticados de trastorno comórbido con TDAH (6,72 % del total de adolescentes atendidos). Estos adolescentes consumían principalmente cannabis, y en menor medida, alcohol y/o cocaína. El diagnóstico de TDAH se realizó de forma previa al consumo de sustancias en 13 de ellos, y aunque 11 habían recibido en algún momento tratamiento farmacológico específico, sólo tres lo tomaban en el momento de la evaluación (cuatro lo habían abandonado voluntariamente, y a cuatro les había sido retirado). Durante el tratamiento, 14 de ellos realizaron tratamiento farmacológico específico para el TDAH. Conclusiones: Se considera que el TDAH con consumo de sustancias presenta mayor gravedad, más alteraciones conductuales y mayor dificultad de tratamiento. Estos resultados apoyan la necesidad de extremar los cuidados y desplegar herramientas que favorezcan la adherencia terapéutica, sobre todo en los primeros meses del programa, así como prestar especial atención al consumo continuado, junto con el adecuado abordaje del TDAH (AU)

Introduction: The relationship between substance use and attention deficit and hyperactivity disorder (ADHD) is considered increasingly important among adolescents and youth. Objetives: The aim of this study is to assess ADHD in adolescent and young people treated in the Program for Adolescents and Families by "Proyecto Hombre" organization (Madrid, Spain). Material and methods: We have included 223 adolescent and young people (75 % male) treated in the Program for Adolescents and Families from 2006 to April 2009. The psychiatric evaluation is conducted of adolescents with psychiatric history, treatment with psychotropic drugs or psychiatric symptoms suggesting. Results: Of the total sample, 15 adolescents (all boys) were diagnosed with ADHD comorbid disorder (6.72 % of all the sample). These adolescents consumed mainly cannabis, and less alcohol and/or cocaine. The diagnosis of ADHD was held prior to substance use in 13 of them; 11 had received any specific drug treatment (only three at the time of evaluation; four had left voluntarily, and in four cases the treatment had been retired). During therapeutic programme, 14 of them receive specific drug treatment for ADHD. Conclusions: Patients with ADHD and substance misuse are more serious, with more important behavioural alterations, and with special difficulties in the treatment. This way, it is important to take special care and to improve the adherence, especially during the first months in the therapeutic program. In addition it's necessary to treat adequately the ADHD (AU)

Understanding medicinal taste and odour formation in drinking waters.

The formation of bromophenols during chlorination of phenol- and bromide-containing waters can be critical for taste and odour problems in drinking waters. The work performed has confirmed that flavour threshold concentrations of some bromophenols are in the ng/L range. In addition, under typical drinking water conditions, kinetic experiments and model simulations performed have shown that (1) bromination is the predominant reaction pathway, (2) bromophenol reaction kinetics are rapid leading to taste-and-odour episodes that last for short periods of 10-20 min, (3) increasing phenol concentration and pH tends to increase taste and odour intensity, (4) increasing chlorine or bromide concentrations tends to shorten the duration of the taste-and-odour episode.

MTBE oxidation by conventional ozonation and the combination ozone/hydrogen peroxide: efficiency of the processes and bromate formation.

The present study investigates the oxidation of methyl tert-butyl ether (MTBE) by conventional ozonation and the advanced oxidation process (AOP) ozone/hydrogen peroxide under drinking water treatment conditions. The major degradation products identified were tert-butyl formate (TBF), tert-butyl alcohol (TBA), 2-methoxy-2-methyl propionaldehyde (MMP), acetone (AC), methyl acetate (MA), hydroxyisobutyraldehyde (HiBA), and formaldehyde (FA). The rate constants of the reaction of ozone and OH radicals with MTBE were found to be 0.14 and 1.9 x 10(9) M(-1) s(-1), respectively. The rate constants for the same oxidation processes were also measured for the degradation products TBF, MMP, MA, and HiBA (k(O3-TBF) = 0.78 M(-1) s(-1); k(OH-TBF) = 7.0 x 10(8) M(-1) s(-1); k(O3-MMP) = 5 M(-1) s(-1); k(OH-MMP) = 3 x 10(9) M(-1) s(-1), k(O3-MA) = 0.09 M(-1) s(-1), k(O3-HiBA) = 5 M(-1) s(-1); k(OH-HiBA) = 3 x 10(9) M(-1) s(-1)). Since all compounds reacted slowly with molecular ozone, only the degradation pathway of MTBE with OH radicals has been determined, including the formation of primary degradation products. In experiments performed with several natural waters, the efficiency of MTBE elimination and the formation of bromate as disinfection byproduct have been measured. With a bromide level of 50 microg/L, only 35-50% of MTBE could be eliminated by the AOP O3/H2O2 without exceeding the current drinking water standard of bromate (10 microg/L). The transient concentrations of MTBE and its primary degradation products were modeled using a combination of kinetic parameters (degradation product distribution and rate constants) together with the ozone and OH radical concentration and were in good agreement with the experimental results.

The role of hydroxyl radicals for the decomposition of p-hydroxy phenylacetic acid in aqueous solutions.

The chemical decomposition of p-hydroxyphenylacetic acid, a priority phenolic pollutant present in wastewaters from some agro-industrial plants, is studied by means of a single photochemical process produced by a polychromatic UV radiation and by hydroxyl radicals generated by the combination of UV radiation plus hydrogen peroxide and by the Fenton's reagent (hydrogen peroxide plus ferrous salts). Batch experiments were conducted to establish the degradation levels obtained and the quantum yields in the single photodecomposition process. An improvement in the decomposition of the phenolic acid in the combined UV/H2O2 oxidation is observed, due to the generation of OH radicals, and the contribution of the radical reaction to the global process is determined. In the Fenton's reagent oxidation, the effects of the operating variables (H2O2 and Fe2+ initial concentrations, pH, type of buffer used) are established and the rate constant for the reaction of p-hydroxyphenylacetic acid with OH radicals is evaluated from a kinetic model, its value being 7.02 x 10(8) M-1 s-1 at 20 degrees C.

Rate constants for the reactions of ozone with chlorophenols in aqueous solutions.

The oxidation by ozone of several chlorophenols (CPs): 4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, 2,3,4, 6-tetrachlorophenol, tetracholorocatechol (3,4,5, 6-tetrachloro-2-hydroxy phenol) and 4-chloroguaiacol (4-chloro-2-methoxy phenol), is studied in order to provide values of the overall rate constant for the reaction between ozone and these chlorophenols. Single ozonation experiments of 4-chlorophenol were conducted in an homogeneous system, and ozonation reactions of CP mixtures were performed in a heterogeneous system, leading to the evaluation of the overall ozonation rate constants in acidic aqueous solutions. These second order rate constants increase several order of magnitude with the pH as does the degree of deprotonation of the dissolved compounds (i.e. from 10(3) to 10(9)l/(mols) for different CPs). The specific rate constants for the ozonation of the non-dissociated and dissociated forms of the studied CPs are also determined and reported. The values obtained allow calculation of the overall rate constants and prediction of the reactivities of the several CPs at different operating conditions in the whole range of pH.

DNA degradation by the mixture of copper and catechol is caused by DNA-copper-hydroperoxo complexes, probably DNA-Cu(I)OOH.

Free hydroxyl radicals (free (.)OH), singlet oxygen ((1)O(2)), or (. )OH produced by DNA-copper-hydroperoxo complexes are possible DNA-damaging reactive oxygen species (ROS) in the reaction system containing copper, catechol, and DNA. para-Chlorobenzoic acid (pCBA) degradation studies revealed that CuCl(2) mixed with catechol produced free (.)OH. In the presence of DNA, however, inhibition of the pCBA degradation suggested that another ROS is responsible for the DNA degradation. Of a series of ROS scavengers investigated, only KI, NaN(3), and Na-formate-all of the salts tested-strongly inhibited the DNA degradation, suggesting that the ionic strength rather than the reactivity of the individual scavengers could be responsible for the observed inhibition. The ionic strength effect was confirmed by increasing the concentration of phosphate buffer, which is a poor (.)OH scavenger, and was interpreted as the result of destabilization of DNA-copper-hydroperoxo complexes. Piperidine-labile site patterns in DNA degraded by copper and catechol showed that the mixture of Cu(II) and catechol degrades DNA via the intermediate formation of a DNA-copper-hydroperoxo complex. Replacement of guanine by 7-deazaguanine did not retard the DNA degradation, suggesting that the DNA-copper-hydroperoxo complexes do not bind to the guanine N-7 as proposed in the literature.

Contribution of free radicals to chlorophenols decomposition by several advanced oxidation processes.

The chemical decomposition of aqueous solutions of various chlorophenols (4-chlorophenol (4-CP), 2,4-dichlorophenol (2-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP)), which are environmental priority pollutants, is studied by means of single oxidants (hydrogen peroxide, UV radiation, Fenton's reagent and ozone at pH 2 and 9), and by the Advanced Oxidation Processes (AOPs) constituted by combinations of these oxidants (UV/H2O2 UV/Fenton's reagent and O3/UV). For all these reactions the degradation rates are evaluated by determining their first-order rate constants and the half-life times. Ozone is more reactive with higher substituted CPs while OH* radicals react faster with those chlorophenols having lower number of chlorine atoms. The improvement in the decomposition levels reached by the combined processes, due to the generation of the very reactive hydroxyl radicals. in relation to the single oxidants is clearly demonstrated and evaluated by kinetic modeling.

Aerobic degradation of olive mill wastewaters.

The degradation of olive mill wastewater by aerobic microorganisms has been investigated in a batch reactor, by conducting experiments where the initial concentration of organic matter, quantified by the chemical oxygen demand, and the initial biomass were varied. The evolution of the chemical oxygen demand, biomass and the total contents of phenolic and aromatic compounds were followed through each experiment. According to the Contois model, a kinetic expression for the substrate utilization rate is derived, and its biokinetic constants are evaluated. This final predicted equation agrees well with all the experimental data.