Electrophysiological correlates of reading in children with attention deficit hyperactivity disorder. / Correlatos electrofisiologicos de la lectura en niños con trastorno por deficit de atencion/hiperactividad.

AIMS: To investigate whether or not the deficits in executive functions in the attention deficit hyperactivity disorder (ADHD) affect reading comprehension and identify a potential biological marker of this neuropsychological endophenotype through event-related potentials (ERP). The phenotypic association between reading comprehension and the specific functions of inhibition and working memory is studied. SUBJECTS AND METHODS: The sample consisted of 52 children with ADHD (8-13 years) divided in two groups according to the presence (TDAH-; n = 27; percentile < 30) or the absence (TDAH+; n = 25; percentile > 50) of reading comprehension deficits and a control group (n = 27). The executive functions were evaluated. The ERPs were assessed during a task in which anaphoric sentences of different lengths were presented, recording the ERP in the last adjective of the sentence that required a gender agreement. RESULTS: Working memory and inhibition were associated to reading comprehension performance. The ADHD+ group and the control group seem to detect the disagreement at 100 ms, while the ADHD- group does not activate its working memory until 250 ms. CONCLUSIONS: The delay in the implementation of the working memory mechanisms helps us to understand the deficits in reading comprehension of the ADHD- group.

TITLE: Correlatos electrofisiologicos de la lectura en niños con trastorno por deficit de atencion/hiperactividad.Objetivos. Investigar si los deficits en las funciones ejecutivas en el trastorno por deficit de atencion/hiperactividad (TDAH) afectan a su compresion lectora e identificar un potencial marcador biologico de este endofenotipo neuropsicologico a traves de potenciales relacionados con eventos. Especificamente, hipotetizar si las diferencias en memoria de trabajo e inhibicion mantienen una asociacion fenotipica con la comprension lectora en el TDAH. Sujetos y metodos. La muestra estuvo constituida por 52 niños con TDAH (8-13 años) divididos en dos grupos segun la presencia (TDAH­; n = 27; percentil < 30) o ausencia (TDAH+; n = 25; percentil > 50) de deficit en compresion lectora y un grupo control (n = 27). Se evaluaron las funciones ejecutivas y se realizo un experimento de potenciales relacionados con eventos en el que se presentaron oraciones anaforicas de diferentes longitudes, y se registraron los potenciales relacionados con eventos en el ultimo adjetivo de la oracion que requiere acuerdo de genero. Resultados. Se encontro una relacion entre memoria de trabajo e inhibicion con el rendimiento en compresion lectora. Mientras que los grupos de TDAH+ y control mostraron signos de deteccion de no concordancia sintactica a los 100 ms, el grupo de TDAH­ no activo la memoria de trabajo hasta los 250 ms. Conclusiones. La lentitud en la puesta en marcha de los mecanismos de memoria de trabajo nos ayuda a entender los deficits en comprension lectora del grupo de TDAH­.

Safe intrathecal fluorescein use for identification of cerebrospinal fluid leaks: Case-report and perioperative algorithm description. / Uso seguro de fluoresceína intratecal en la localización de las fístulas de líquido cefalorraquídeo: descripción de un caso e implementación de un algoritmo perioperatorio.

Intrathecal injection of fluorescein is a method for repairing cerebrospinal fluid fistulas. The most frequent surgical procedure is endonasal endoscopy and the purpose of injecting this dye is to locate the fistula. The anaesthesiologists usually perform the puncture, therefore it is necessary to review this method and to specify some anaesthetic considerations such as correct dosing, safe management protocols and medical-legal aspects. In this case-report we describe the pre, intra and postoperative protocol of action implemented in our department that basically consists of: obtaining a specific consent, prior neurological/ophthalmologic assessment to rule out hypertension and brain damage, use of corticosteroids and previous antihistamines, choosing the correct dose and concentration of intrathecal sodium fluorescein (maximum 1ml at a concentration of 5% diluted in 9ml of cerebrospinal fluid) and close intra and postoperative monitoring.

Simulating the folding of HP-sequences with a minimalist model in an inhomogeneous medium.

The phenomenon of protein folding is a fundamental issue in the field of the computational molecular biology. The protein folding inside the cells is performed in a highly inhomogeneous, tortuous, and correlated environment. Therefore, it is important to include in the theoretical studies the medium where the protein folding is developed. In this work we present the combination of three models to mimic the protein folding inside of an inhomogeneous medium. The models used here are Hydrophobic-Polar (HP) in 2D square arrangement, Evolutionary Algorithms (EA), and the Dual Site Bond Model (DSBM). The DSBM model is used to simulate the environment where the HP beads are folded; in this case the medium is correlated and is fractal-like. The analysis of five benchmark HP sequences shows that the inhomogeneous space provided with a given correlation length and fractal dimension plays an important role for correct folding of these sequences, which does not occur in a homogeneous space.

The cannabinoid receptor 1 gene (CNR1) and multiple sclerosis: an association study in two case-control groups from Spain.

Different studies point to the implication of the endocannabinoid system in multiple sclerosis (MS) and animal models of MS. The purpose of this study was to evaluate a possible association of MS with polymorphic markers at the CNR1 gene, encoding the cannabinoid 1 (CB(1)) receptor. We have performed a genetic analysis of an AAT repeat microsatellite localized in the downstream region of the CNR1 gene, in two case-control groups of MS patients and healthy controls (HC) from Spain (Madrid and Bilbao). MS patients with primary progressive MS (PPMS) had more commonly long ((AAT) > or = (13)) alleles and genotypes with a significant difference for genotype 7/8 in Madrid (p = 0.043) and in the sum of both groups (p = 0.016); short alleles were less frequently found in PPMS with a significant difference for allele 5 in the analysis of both groups together (p = 0.039). In patients with relapsing MS, no consistent differences in allele and genotype distribution were found. Disease severity and progression was unrelated to AAT repeat variations. In conclusion, long (AAT) > or = (13) CNR1 genotypes could behave as risk factors for PPMS.

[Neuropsychological assessment of memory in attention deficit hyperactivity disorder: the role of executive functions]. / Evaluación neuropsicológica de la memoria en el trastorno pordéficit de atención/hiperactividad: papel de las funciones ejecutivas.

INTRODUCTION: There is an important agreement on the consideration of attention deficit hyperactivity disorder (ADHD) as a condition characterized by neurodevelopmental dysfunction of fronto-striatal dopaminergic and noradrenergic circuits with resultant executive deficits in cognitive functioning. AIM: To assess the existence of memory deficits in children with ADHD associated with a poor performance executive. SUBJECTS AND METHODS: We assess 14 children diagnosed with ADHD combined type and 14 controls matched on intellectual coefficient, age and level of schooling, in a neuropsychological evaluation protocol designed to assess executive functions and memory skills using Auditory Verbal Learning Test, Memory for Stories Test -Test of Memory and Learning (TOMAL)-, Complex Figure Text, Visual Selective Reminding Test (TOMAL), Tower of Hanoi, Memory Phrases Test (Siegel and Ryan), Digit Span (Wechsler Intelligence Scale for Children-Revised) and Tapping Test (Wechsler Memory Scale III). RESULTS: The ADHD group showed deficits in the learning and free recall of verbal material, in procedural and working memory. No group differences were observed in the visual memory tasks. CONCLUSIONS: The results are analyzed in terms of difficulty in coding strategies, storage and search of information previously stored in the group with ADHD, at least for the kind of verbal information. These difficulties are associated with deficits in executive functioning.

[Neuropsychological assessment of the effectiveness of OROS-methylphenidate in attention deficit hyperactivity disorder]. / Evaluación neuropsicológica de la eficacia del metilfenidato-OROS en el trastorno por deficit de atención/hiperactividad.

INTRODUCTION: There is wide evidence about dopaminergic and noradrenergic mechanisms in fronto-striatal circuits which are thought to be related with attention deficit hyperactivity disorder (ADHD) neurobiology. That dysfunction may explain core symptoms and part of executive deficits in cognitive functioning. Methylphenidate is effective in alleviating core symptoms, enhancing dopaminergic and noradrenergic biodisponibility. Less evidence in improving executive functions, specially working memory is found. AIMS: To assess if methylphenidate-OROS has a potential effect increasing working memory and attention parameters in ADHD children, and to determine if initial working memory and attention differences between ADHD and control group disappear after one month of daily methylphenidate-OROS treatment. SUBJECTS AND METHODS: Eleven children with ADHD were selected and as control group was chosen eleven children compared in age, intelligence quotient, school grade, and social-demographic status. Neuropsychological battery was administered in naive ADHD patients at three times, before treatment, after the first methylphenidate-OROS dose, and after one month of daily treatment. Simultaneously neuropsychological battery was administered to control group. RESULTS. Statistically significant differences were found in neuropsychological variables of working memory after one month daily treatment with methylphenidate-OROS and attention parameters after only one dose in ADHD group. Differences between naive ADHD and control group in terms of working memory were statistically significant before treatment but not after one month daily treatment. CONCLUSION: Methylphenidate-OROS improves attention achievement after the first dose and working memory after one month of daily treatment.

Vincristine-induced acute neurotoxicity versus Guillain-Barré syndrome: a diagnostic dilemma.

We report the case of a patient with acute lymphoblastic leukaemia who, after the initiation of treatment with vincristine (VCR), developed a fulminant motor polyradiculoneuropathy resembling an axonal variant of Guillain-Barré syndrome (GBS). This report shows that differentiating between axonal GBS and VCR-induced acute neurotoxicity may be a challenge for clinicians.

Shift-back of right into left hemisphere language dominance after control of epileptic seizures: evidence for epilepsy driven functional cerebral organization.

Atypical, i.e. right hemisphere language dominance is frequently observed in early onset left hemisphere epilepsies. In left mesial temporal lobe epilepsy, where eloquent cortex is not directly involved, it is a matter of debate, to which degree atypical language dominance is driven not only by morphological lesions but also by epileptic dysfunction, and whether atypical dominance is hardwired or not. Taking this as the background this study evaluated the hypothesis that epilepsy driven atypical dominancy might be reversible when seizures are successfully controlled. This was evaluated in patients with left mesial temporal lobe epilepsy, who were atypically language dominant by means of language fMRI before surgery, and became seizure free after left selective amygdalo-hippocampectomy. Three out of 53 consecutive atypically dominant patients with chronic epilepsy fulfilled these criteria. Postoperative follow-up language fMRI indicated reversal of right into left dominance in one patient going along with unexpected losses in verbal memory performance. The two other patients experienced unchanged or even enhancement of the pre-existing dominance pattern, going along with consistent postoperative performance changes in cognition. The data thus provide supporting evidence that atypical language dominance can indeed be functionally driven and moreover that in at least some patients, right hemispheric language can shift-back to the left hemisphere when the driving factor, i.e. seizures, becomes successfully controlled. The results have clinical implications for outcome prediction after brain surgery in atypically dominant patients with epilepsy. However, further research in larger groups of atypically dominant patients is required to identify the conditions under which atypical dominance becomes hardwired and when not.

[New procedure for the early detection and control of hospital malnutrition]. / Nuevo procedimiento para la detección precoz y control de la desnutrición hospitalaria.

The serious problem of hospital undernutrition is still being underestimated by medical staff of modern hospitals, despite its impact on clinical evolution and hospitalisation costs. The actual system used to detect undernutrition in hospitals depends on doctor's sensitivity and not even the 10% of the cases that require intervention are detected. The screening methods developed so far are not useful for daily clinical practice due to their low effectiveness/cost ratio. We present a screening method that allows an automatic daily assessment of nutritional status, of all inpatients that undergo routine analysis. The system is based on a computer application that compiles daily all patients' information available in hospital databases, through the internal network. It automatically assesses the nutritional status of patients taking into account laboratory information concerning albumin, total cholesterol and total lymphocyte count. This tool also provides diagnostic and patients data for physicians' usage. The screening method has been validated, obtaining a sensitivity of 92.3 and specificity of 85.0, considering only laboratory information. This is an efficient tool for early detection and permanent control of hospital undernutrition, with the suitable characteristics for these screening functions, such as its sensitivity, specificity, universality, economy and harmlessness, as well as a great versatility for undertaking a high number of studies regarding the hospital undernutrition problem. We trust that working with it we will obtain a remarkable welfare improvement as well as make aware to people in charge of Public Health of the magnitude of the undernutrition's derived consequences of hospital's in-patients, and after discharge.