[Management of pediatric status epilepticus]. / Revisión del estado epiléptico convulsivo pediátrico y su manejo antiepiléptico.

Pediatric Status Epilepticus (SE) is an emergency situation with high morbidity and mortality that requires early and aggressive management. The minimum time criterion to define SE was reduced from 30 to 5 minutes, defined as continuous seizure activity or rapidly recurrent seizures without resumption of consciousness for more than 5 minutes. This definition considers that seizures that persist for > 5 minutes are likely to do so for more than 30 min. Those that persist for more than 30 minutes are more difficult to treat. Refractory SE is the condition that extends beyond 60-120 minutes and requires anesthetic management. Super-refractory SE is the state of no response to anesthetic management or relapse during withdrawal of these drugs. The aim of this review is to provide and update on convulsive SE concepts, pathophysiology, etiology, available antiepileptic treatment and propose a rational management scheme. A literature search of articles published between January 1993 and January 2013, focused on pediatric population was performed. The evidence about management in children is limited, mostly corresponds to case series of patients grouped by diagnosis, mainly adults. These publications show treatment alternatives such as immunotherapy, ketogenic diet, surgery and hypothermia. A 35% mortality, 26% of neurological sequelae and 35% of recovery to baseline condition is described on patient’s evolution.

Evaluation of stable isotope fingerprinting techniques for the assessment of the predominant methanogenic pathways in anaerobic digesters.

Laboratory biogas reactors were operated under various conditions using maize silage, chicken manure, or distillers grains as substrate. In addition to the standard process parameters, the hydrogen and carbon stable isotopic composition of biogas was analyzed to estimate the predominant methanogenic pathways as a potential process control tool. The isotopic fingerprinting technique was evaluated by parallel analysis of mcrA genes and their transcripts to study the diversity and activity of methanogens. The dominant hydrogenotrophs were Methanomicrobiales, while aceticlastic methanogens were represented by Methanosaeta and Methanosarcina at low and high organic loading rates, respectively. Major changes in the relative abundance of mcrA transcripts were observed compared to the results obtained from DNA level. In agreement with the molecular results, the isotope data suggested the predominance of the hydrogenotrophic pathway in one reactor fed with chicken manure, while both pathways were important in the other reactors. Short-term changes in the isotopic composition were followed, and a significant change in isotope values was observed after feeding a reactor digesting maize silage. This ability of stable isotope fingerprinting to follow short-term activity changes shows potential for indicating process failures and makes it a promising technology for process control.

Influence of the maize silage to grass silage ratio and feed particle size of rations for ruminants on the community structure of ruminal Firmicutes in vitro.

AIMS: To investigate the effect of the forage source and feed particle size (FPS) in ruminant rations on the composition of the ruminal Firmicutes community in vitro. METHODS AND RESULTS: Three diets, varying in maize silage to grass silage ratio and FPS, were incubated in a rumen simulation system. Microbial samples were taken from the liquid fermenter effluents. Microbial community analysis was performed by 16S rRNA-based techniques. Clostridia-specific single-strand conformation polymorphism profiles revealed changes of the community structure in dependence on both factors tested. The coarse grass silage-containing diets seemed to enhance the occurrence of different Roseburia species. As detected by real-time quantitative PCR, Ruminococcus albus showed a higher abundance with decreasing FPS. A slightly lower proportion of Bacilli was found with increasing grass silage to maize silage ratio by fluorescence in situ hybridization (FISH). In contrast, a slightly higher proportion of bacterial species belonging to the Clostridium-clusters XIV a and b was detected by FISH with increasing grass silage contents in the diet. CONCLUSIONS: The ruminal Firmicutes community is affected by the choice of the forage source and FPS. SIGNIFICANCE AND IMPACT OF THE STUDY: This study supplies fundamental knowledge about the response of ruminal microbial communities to changing diets. Moreover, the data suggest a standardization of grinding of feeds for in vitro studies to facilitate the comparison of results of different laboratories.

Phylogenetic and proteomic analysis of an anaerobic toluene-degrading community.

AIMS: This study intended to unravel the physiological interplay in an anaerobic microbial community that degrades toluene under sulfate-reducing conditions combining proteomic and genetic techniques. METHODS AND RESULTS: An enriched toluene-degrading community (Zz5-7) growing in batch cultures was investigated by DNA- and protein-based analyses. The affiliation and diversity of the community were analysed using 16S ribosomal RNA (rRNA) genes as a phylogenetic marker as well as bssA and dsrAB genes as functional markers. Metaproteome analysis was carried out by a global protein extraction and a subsequent protein separation by two-dimensional gel electrophoresis (2-DE). About 85% of the proteins in the spots were identified by nano-liquid chromatography coupled with electrospray mass spectrometry (nano-LC-ESI-MS/MS) analysis. DNA sequencing of bssA and the most abundant dsrAB amplicons revealed high similarities to a member of the Desulfobulbaceae, which was also predominant according to 16S rRNA gene amplicons. Metaproteome analysis provided 202 unambiguous protein identifications derived from 236 unique protein spots. The proteins involved in anaerobic toluene activation, dissimilatory sulfate reduction, hydrogen production/consumption and autotrophic carbon fixation were mainly affiliated to members of the Desulfobulbaceae and several other Deltaproteobacteria. CONCLUSION: Phylogenetic and metaproteomic analyses revealed a member of the Desulfobulbaceae as the key player of anaerobic toluene degradation in a sulfate-reducing consortium. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study that combines genetic and proteomic analyses to indicate the interactions in an anaerobic toluene-degrading microbial consortium.

Effect of the corn silage to grass silage ratio and feed particle size of diets for ruminants on the ruminal Bacteroides-Prevotella community in vitro.

This study examined whether different corn silage to grass silage ratios in ruminant rations and different grinding levels of the feed affect the composition of the ruminal Bacteroides-Prevotella community in vitro. Three diets, composed of 10% soybean meal as well as of different corn silage and grass silage proportions, were ground through 1mm or 4mm screened sieves and incubated in a semi-continuous rumen simulation system. On day 14 of the incubation microbes were harvested by centrifugation from the liquid effluent of fermenter vessels. Microbial DNA was extracted for single strand conformation polymorphism (SSCP) analysis of 16S rRNA genes followed by sequencing of single SSCP bands. Fluorescence in situ hybridization (FISH) and real-time quantitative (q) PCR were used to quantify differences in the relative abundance of Bacteroides-Prevotella and Prevotella bryantii. SSCP profiles revealed a significant influence of the forage source as well as of the feed particle size on the community structure of the Bacteroides-Prevotella group. Different, phylogenetically distinct, so far uncultured Prevotella species were detected by sequence analysis of several treatment-dependent occurring SSCP bands indicating different nutritional requirements of these organisms for growth. No quantitative differences in the occurrence of Bacteroides-Prevotella-related species were detected between diets by FISH with probe BAC303. However, real-time qPCR data revealed a higher abundance of P. bryantii with increasing grass silage to corn silage ratio, thus again indicating changes within the community composition of the Bacteroides-Prevotella group. As P. bryantii possesses high proteolytic activity its higher abundance may have been caused by the higher contents of crude protein in the grass silage containing diets. To conclude, results of this study show an influence of the forage source on the ruminal community of Bacteroides-Prevotella. Furthermore, they suggest an effect of the feed particle size on this bacterial group.

Dynamics of polyphosphate-accumulating bacteria in wastewater treatment plant microbial communities detected via DAPI (4',6'-diamidino-2-phenylindole) and tetracycline labeling.

Wastewater treatment plants with enhanced biological phosphorus removal represent a state-of-the-art technology. Nevertheless, the process of phosphate removal is prone to occasional failure. One reason is the lack of knowledge about the structure and function of the bacterial communities involved. Most of the bacteria are still not cultivable, and their functions during the wastewater treatment process are therefore unknown or subject of speculation. Here, flow cytometry was used to identify bacteria capable of polyphosphate accumulation within highly diverse communities. A novel fluorescent staining technique for the quantitative detection of polyphosphate granules on the cellular level was developed. It uses the bright green fluorescence of the antibiotic tetracycline when it complexes the divalent cations acting as a countercharge in polyphosphate granules. The dynamics of cellular DNA contents and cell sizes as growth indicators were determined in parallel to detect the most active polyphosphate-accumulating individuals/subcommunities and to determine their phylogenetic affiliation upon cell sorting. Phylotypes known as polyphosphate-accumulating organisms, such as a "Candidatus Accumulibacter"-like phylotype, were found, as well as members of the genera Pseudomonas and Tetrasphaera. The new method allows fast and convenient monitoring of the growth and polyphosphate accumulation dynamics of not-yet-cultivated bacteria in wastewater bacterial communities.

Physiological and genetic characteristics of two bacterial strains utilizing phenoxypropionate and phenoxyacetate herbicides.

Two strains, Rhodoferax sp. P230 and Delftia (Comamonas) acidovorans MCI, have previously been shown to carry activities for the degradation of the two enantiomers of (RS)-2-(2,4-dichlorophenoxy-)propionate (dichlorprop) and (RS)-2-(4-chloro-2-methylphenoxy-)propionate (mecoprop) and, in addition, are capable of degrading phenoxyacetate derivatives 2.4-dichlorophenoxyacetate (2,4-D) and 4-chloro-2-methylphenoxyacetate (MCPA). Metabolism of the herbicides is initiated by alpha-ketoglutarate-dependent dioxygenases for both enantiomers of the phenoxypropionate herbicides and for 2,4-D. These activities were constitutively expressed for both enantiomers of dichlorprop in strain MC1 and for the Renantiomer in strain P230. Enzyme activities for the complete degradation of phenoxyacetate and phenoxypropionate herbicides were induced during incubation on either of these herbicides. Strain MC1 has about threefold higher activities for the degradation of dichlorprop and for growth on this substrate (mumax = 0.15 h(-1)) than strain P230; the maximum growth rate on 2,4-D amounts to 0.045 h(-1) with strain MC1. Dichlorprop is utilized faster than mecoprop and the R-enantiomers are cleaved with higher rates than the S-enantiomers. The degradation of the chlorophenolic intermediates seems to proceed via the modified ortho cleavage pathway as indicated by activities of the respective enzymes. The enzymatic results were supported by genetic investigations by which the presence of the genes tfdB (encoding a dichlorophenol hydroxylase), tfdC (encoding a chlorocatechol 1,2-dioxygenase) and tfdD (encoding a chloromuconate cycloisomerase) could be demonstrated in both strains by PCR after application of respective primers. The presence of the tfdA gene (encoding a 2,4-D/alpha-ketoglutarate dioxygenase) was only shown for strain P230 but was lacking in strain MC1. Sequence analysis of the tfd gene fragments revealed high homology to the degradative genes of other proteobacterial strains degrading chloroaromatic compounds. Strain MC1 carries a plasmid of about 120 kb which apparently harbors herbicide degradative genes as concluded from deletion mutants which have lost 2,4-D[phenoxalkanoate]/alpha-ketoglutarate dioxygenase activities for cleavage of the R- and S-enantiomer, and of 2,4-D. For strain P230, no plasmid could be demonstrated; the activity was stably conserved in this strain during growth under nonselective conditions.

Comamonas acidovorans strain MC1: a new isolate capable of degrading the chiral herbicides dichlorprop and mecoprop and the herbicides 2,4-D and MCPA.

A gram-negative prototrophic bacterial species, strain MC1, was isolated from the vicinity of herbicide-contaminated building rubble and identified by 16S rDNA sequence analysis, its physiological properties, GC content, and fatty acid composition as Comamonas acidovorans. This strain displays activity for the productive degradation of the two enantiomers of dichlorprop [(RS)-2-(2,4-dichlorophenoxy-)propionate; (RS)-2,4-DP] and mecoprop [(RS)-2-(4-chloro-2-methyl-) phenoxypropionate; (RS)-MCPP] in addition phenoxyacetate herbicides, i.e. 2,4-dichlorophenoxyacetate (2,4-D) and 4-chloro-2-methylphenoxyacetate (MCPA), and various chlorophenols were utilized. Rates amounted to 1.2 mmoles/h g dry mass (2,4-D) and 2.7 mmoles/h g dry mass [(RS)-2,4-DP]. Degradation of (RS)-2,4-DP was not inhibited up to concentrations of 500 mg/l, nor of 2,4-D up to 200 mg/l. The optimum pH value of (RS)-2,4-DP degradation was around 8. The application of respective primers for PCR amplification revealed the presence of tfdB and tfdC genes.

Methanogenic Community Dynamics during Anaerobic Utilization of Agricultural Wastes.

This work is devoted to the investigation of the methanogenic archaea involved in anaerobic digestion of cattle manure and maize straw on the basis of terminal restriction fragment length polymorphism (T-RFLP) analysis of archaeal 16S rRNA genes. The biological diversity and dynamics of methanogenic communities leading to anaerobic degradation of agricultural organic wastes with biogas production were evaluated in laboratory-scale digesters. T-RFLP analysis, along with the establishment of archaeal 16S rRNA gene clone libraries, showed that the methanogenic consortium consisted mainly of members of the generaMethanosarcinaandMethanoculleus,with a predominance ofMethanosarcinaspp. throughout the experiment.

Revisión del estado epiléptico convulsivo pediátrico y su manejo antiepiléptico / Management of pediatric status epilepticus

Pediatric Status Epilepticus (SE) is an emergency situation with high morbidity and mortality that requires early and aggressive management. The minimum time criterion to define SE was reduced from 30 to 5 minutes, defined as continuous seizure activity or rapidly recurrent seizures without resumption of consciousness for more than 5 minutes. This definition considers that seizures that persist for > 5 minutes are likely to do so for more than 30 min. Those that persist for more than 30 minutes are more difficult to treat. Refractory SE is the condition that extends beyond 60-120 minutes and requires anesthetic management. Super-refractory SE is the state of no response to anesthetic management or relapse during withdrawal of these drugs. The aim of this review is to provide and update on convulsive SE concepts, pathophysiology, etiology, available antiepileptic treatment and propose a rational management scheme. A literature search of articles published between January 1993 and January 2013, focused on pediatric population was performed. The evidence about management in children is limited, mostly corresponds to case series of patients grouped by diagnosis, mainly adults. These publications show treatment alternatives such as immunotherapy, ketogenic diet, surgery and hypothermia. A 35% mortality, 26% of neurological sequelae and 35% of recovery to baseline condition is described on patient’s evolution.

Ultrasonido: una alternativa en la evaluación del diafragma en niños con distrofia muscular de Duchenne / Ultrasound, an alternative in the evaluation of the diaphragm in children with Duchenne muscular dystrophy

The outcome of children with Duchenne muscular dystrophy (DMD) depends on respiratory involvement, so a timely assessment of the diaphragm is required. We propose ultrasound (US) imaging as an alternative in the evaluation of the diaphragm in children with DMD, correlating diaphragmatic thickness and excursion values yielded by the US study with pulmonary function tests. We conducted a case-control study including 27 children, 15 controls and 12 patients. Excursion and thickness of both hemidiaphragms were measured by U.S., and spirometry was performed. The DMD group showed less excursion and a significantly higher thickness of the right hemidiaphragm; 60 percent of patients showed spirometric restrictive pattern and FEV1, FVC, PEF and PIM values were significantly lower. We found a negative trend when correlating diaphragmatic excursion with pulmonary function tests. We conclude that the US technique is suitable for screening alterations in diaphragmatic excursion and thickness in children with DMD, since it provides supporting data to pulmonary function tests.

El pronóstico de los niños con distrofia muscular de Duchenne (DMD) depende del compromiso respiratorio, siendo necesaria la evaluación oportuna del diafragma. Proponemos el ultrasonido (US) como alternativa en la evaluación del diafragma en niños con DMD, correlacionando los valores de excursión y grosor del diafragma obtenido con US, con las pruebas de función pulmonar. Realizamos un estudio de casos y controles, incluyendo 27 niños, 15 controles y 12 pacientes. Se midió excursión y grosor de ambos hemidiafragmas con US; se realizó espirometría y pimometría. El grupo DMD presentó menor excursión y grosor significativamente mayor del hemidiafragma derecho; el 60 por ciento mostró patrón restrictivo en la espirometría y los valores de VEF1, CVF, FEP y PIM fueron significativamente menores. Encontramos una tendencia negativa al correlacionar la excursión diafragmática con las pruebas de función pulmonar. Concluimos que el US es apto para pesquisar alteraciones en la excursión y grosor del diafragma en niños con DMD, apoyando las pruebas de función pulmonar.

Expression of the dnaB gene of Escherichia coli is inducible by replication-blocking DNA damage in a recA-independent manner.

The replicative DNA helicase encoded by the dnaB gene is essential for chromosomal DNA replication in Escherichia coli. The DnaB protein is a component of the phi X-type primosome which is regarded as a model system for lagging strand synthesis of the chromosome. Using translational lacZ fusions at the plasmid and chromosomal levels, we studied the influence of DNA-damaging agents on dnaB gene expression. We found that DNA damage caused by mitomycin C, methyl methanesulphonate, 4-nitro-quinoline N-oxide, and UV irradiation led to a moderate, but significant induction of dnaB gene expression. Comparative S1 analysis of transcripts in untreated and induced cells demonstrated that the induction is due to increased transcription from the dnaB promoter. In contrast to other DNA damage-inducible replication genes, such as dnaA, dnaN, dnaQ, and polA, expression of which is not inducible in recA and lexA mutants, the induction of dnaB was also observed in a recA1 mutant. These results show that the induction of dnaB gene expression by replication-blocking DNA damage is due to a mechanism other than the indirectly SOS-dependent induction of the other DNA replication genes. Moreover, the data suggest that replication proteins are involved in recovery from replication-blocking DNA damage in two different ways--on the one hand at the level of initiation and on the other hand at the level of elongation.

Expression of the 2,4-D degradative pathway of pJP4 in an alkaliphilic, moderately halophilic soda lake isolate, Halomonas sp. EF43.

The broad host range plasmid pJP4, which carries genes for the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D), 2-methyl-4-chlorophenoxyacetic acid, and 3-chlorobenzoic acid, was used in conjugation experiments with mixed cultures enriched from water and sediment samples from an alkaline pond in the area of Szegedi Fehértó, a soda lake in south Hungary. pJP4-encoded mercury resistance was used as a selection marker. One of the transconjugants, the alkaliphilic, moderately halophilic strain EF43, stably maintained the plasmid and was able to degrade 2,4-D and 3-chlorobenzoate under alkaline conditions in the presence of an additional carbon source such as pyruvate, benzoate, or alpha-ketoglutarate, indicating that the degradative genes of pJP4 were expressed in this strain. However, it was unable to grow on these chloroaromatic substrates when the substrate was the sole source of carbon and energy. Chemostat cultivation experiments revealed that the 2,4-D degradation rate during growth on benzoate or pyruvate was limited by the low activity of chlorocatechol-degrading enzymes, particularly chloromuconate cycloisomerase. Strain EF43 was identified as Halomonas sp. on the basis of 16S rRNA sequencing and additional taxonomic studies. 16S rRNA sequence analysis revealed that strain EF43 is closely related to typical soda lake isolates belonging to the genus Halomonas.

Degradation of various chlorophenols under alkaline conditions by gram-negative bacteria closely related to Ochrobactrum anthropi.

From concrete debris of a demolished herbicide production plant several Gram-negative bacterial strains were isolated, which exhibit metabolic capabilities for the degradation of 2,4-dichlorophenol (DCP)l), 4-chloro-2-methylphenol (MCP) and 4-chlorophenol (4-CP), while 2-chlorophenol (2-CP) was degraded at a slower rate. Degradative activity was inducible and was impeded by adding of 100 mg/l of chloramphenicol to growing cultures. The strains displayed alkaliphilic properties with optimum DCP/MCP degradation at pH values around 8.5-9.5; activity was observed up to pH values of 11. Degradation was most likely complete according to chlorine balances; formation of intermediary products was observed with MCP some time. Specific activity of up to 380 mumol/h.g dry mass was found within the concentration range of 10-20 mg/l DCP; higher concentrations retarded the activity with complete inhibition at 200-400 mg/l. Some of the strains carry plasmids whose presence was not unambiguously correlated to the degradative properties. Ribotyping revealed a high degree of relationship between the strains. Preliminary taxonomic investigations showed close relationship to Ochrobactrum anthropi.

Estado epiléptico no convulsivo en niños / Non convulsive status epilepticus in children

Con el objeto de dar más difusión y estimular el interés en la identificación y seguimiento de pacientes con estados epilépticos no convulsivos, se describen 5 pacientes de 6 a 18 años de edad, en quienes se comprobó, mediante electroencefalogramas seriados y regsitros de video-electroencefalograma, estado parcial complejo (2 pacientes), estado de ausencias (2 pacientes) y estado epiléptico del sueño (1 paciente). La forma clínica de presentación fue similar en todos, caracterizándose por alteración cualitativa de la conciencia o alteración de la conducta de al menos 24 horas de duración, concomitante con actividad epileptiforme en el electroencefalograma. La respuesta a tratamiento fue variable, observándose recurrencia de crisis en los dos casos de estado parcial complejo, persistencia de las manifestaciones clínicas en uno de los niños con estado de ausencia en el que sufría estado epiléptico del sueño. El estado epiléptico no convulsivo debe considerarse en el diagnóstico diferencial de cualquier alteración cualitativa de conciencia, especialmente en pacientes epilépticos

Mialgias post ejercicios como forma de presentación de una distrofinopatía / Post exercise myalgias as form of dystrophynopathy

Cramps and myalgias are frequent presentations of many disorders whose diagnosis is generally difficult. Among the unusual causes stand the milder phenotypes of dystrophinopathies, which are caused, just as Duchenne and BeckerÕs dystrophy, by mutations in the dystrophin gene. An 8 year-old boy presented severe muscle pain on exercise and serum rise in creatine kinase over 1000 U/l. He had normal muscle power and mild calf hypertrophy. The molecular analysis by polymerase chain reaction (PCR) of the dystrophin gene showed deletions of exons 45 to 51. Dystrophin analysis by Western blot revealed a dystrophin of reduced quantity and molecular weight. Emphasis is made to include dystrophinopathies in the differential diagnosis of myalgias and the usefulness of molecular genetic techniques in the identification of these disorders

Enfermedades neurogenéticas en niños y adolescentes / Neurogenetics diseases in children y adolescents

Los avances en el conocimiento de la genética, han modificado en forma determinante la práctica de la Neurología clínica, aportando a una explosiva expansión del área de las enfermedades Neurogenéticas. El advenimiento de nuevas técnicas de genética molecular; las investigaciones en el genoma humano y la descripción de nuevas formas de herencia, han contribuido a la comprensión de la fisiopatología de estas condiciones y han abierto nuevas perspectivas para su tratamiento. En este articulo se describen los mecanismos clásicos y "no tradicionales" de herencia de las enfermedades neurogenéticas, se destaca los elementos cínicos que orientan a su diagnóstico y se revisa las enfermedades de diagnóstico más frecuente: su presentación clínica, las correlaciones genotipo/fenotipo, los estudios recomendados para su diagnóstico y consejo genético.

The great advances in genetic research reached during last years, have deeply modified the routine clinical practice in Neurology, with an specific impact in the expanding field of neurogenetíc dísorders. New technologies in molecular genetics, the research in the human genome and the description of new forms of inheritance have contributed to the understanding of the physíopathology of these conditions and ha ve also open new perspectives to their treatment. In this report we describe classic and "non traditional" mechanisms of inheritance of neurogenetic disorders, highlighting the key clinical fea tu res to suspect their diagnosis. The most frequent neurogenetic disorders are reviewed, special/y regarding their clinical presentation, genotype/phenotype correlation, recommended methodology used for the diagnosis and genetíc counseling.

Evaluación y manejo de la cefalea en el niño / Evaluation and management of headache in children

La cefalea es un síntoma frecuente en niños y adolescentes. Su evaluación incluye anamnesis y examen neurológico completos. Luego de éstos, en la mayoría de los casos es posible definir si se trata de una cefalea primaria o secundaria. La indicación de exámenes de laboratorio y/o neuroimágenes debe hacerse sólo después de efectuar la evaluación clínica. Hecho el diagnóstico, el manejo se basa en la resolución de la causa en las cefaleas secundarias; en cambio, en las cefaleas primarias la terapia se define según la frecuencia y severidad del dolor e impacto en la calidad de vida del niño.

Headache is a frequent symptom in children and adolescents. Complete anamnesis and neurological examination are needed to define if headache is primary or secondary. Additional studies are indicated in specific clinical contexts and after a complete evaluation. In secondary headaches the treatment is oriented to the specific etiology. In primary headache, treatment depends on frequency and severity of pain, and mainly considering the impact on the child's quality of life.

Neurobiologia y diagnóstico del trastorno por déficit de atención / The neurobiology of attention deficit/hyperactivity disorder

El trastorno por déficit de atención e hiperactividad (TOAH) es la condición neurobiológica más prevalente en niños y adolescentes, asociada a importante impacto funcional, personal, familiar y social. La evidencia científica actual provee de fundamentos sólidos acerca de sus bases neurobiológicas: alta heredabilidad, identificación de varios genes implicados en su etiología; perfil neuropsicológico con evidencias de disfunción ejecutiva, desregulación motivación/recompensa, déficits en activación; alteraciones estructurales y de funcionamiento de la corteza prefrontal (CPF) y sus conexiones con el striatum y cerebelo; desbalances de los sistemas dopaminérgico y noradrenérgico, blancos de los tratamientos farmacológicos. En esta revisión se destaca los aportes de las aproximaciones multidisciplinarias (p.e. genética/neuropsicológica/imágenes funcionales) para la comprensión de esta condición heterogénea que se conceptualiza hoy como multifactorial en su origen y con múltiples procesos fisiopatológicos subyacentes. La activa investigación en curso, acerca la posibilidad de contar con marcadores biológicos para el diagnóstico de TDAH y con información gen ética de valor para la elección de fármacos de mayor efectividad y menos efectos adversos.

Attention-deficit/hyperactivity disorder is the most prevalent neurobiological condition in children and adolescents, with significant personal and social functional impairments. There is now strong scientific data providing foundation to its biologic basis. High heritability; several genes involved in its etiology; neuropsychological profile showing executive dysfunction, motivation/reward, dysregulation and activation deficits; altered structure and function of prefrontal cortex and its striatal and cerebellar connections, imbalance of dopaminergic and noradrenergic systems, target of pharmacologic treatment. In this review the contribution af multidisciplinary studies (genetic/neuropsychology/ functional imaging) to the comprehension of this complex and multifactarial canditian is highlighted. Ongoing active research promises new important developments such as biolagic diagnostic markers far clinical purpases and useful genetic data in order ta select pharmacologic treatment, improve efficiency and reduce side effects.

Compromiso multisistémico: ¿y si fuera una enfermedad mitocondrial / Multisystemic involvement: and if it was a mitochondrial disease?

Las mitocondrias como organelos subcelulares claves en la generación de la energía son esenciales para la supervivencia de la vida humana. Sus alteraciones conocidas en la actualidad como enfermedades o citopatías mitocondriales se han constituido en la última década en un área de acelerado desarrollo que involucra a todas las especialidades de la medicina. Focos de estudio de especial interés son la herencia "no tradicional" de estos trastornos con un doble control genético (nuclear y mitocondrial); la expresión variable de estas enfermedades en distintos tejidos (multisistémicas o multitisulares) y el creciente diagnóstico de estos cuadros que parecen ser más frecuentes.