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1.
Antimicrob Agents Chemother ; : e0048924, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775484

RESUMEN

Human adenoviruses can cause serious, disseminated infections in immunocompromised patients. For pediatric allogeneic stem cell transplant patients, the case fatality rate can reach 80%. Still, there is no available antiviral drug that is specifically approved by the Food and Drug Administration for the treatment of adenovirus infections. To fill this pressing medical need, we have developed NPP-669, a prodrug of cidofovir with broad activity against double-stranded DNA viruses, including adenoviruses. Here, we report on the in vivo anti-adenoviral efficacy of NPP-669. Using the immunosuppressed Syrian hamster as the model, we show that NPP-669 is highly efficacious when dosed orally at 1 mg/kg and 3 mg/kg. In a delayed administration experiment, NPP-669 was more effective than brincidofovir, a similar compound that reached Phase III clinical trials. Furthermore, parenteral administration of NPP-669 increased its efficacy approximately 10-fold compared to oral dosing without apparent toxicity, suggesting that this route may be preferable in a hospital setting. Based on these findings, we believe that NPP-669 is a promising new compound that needs to be further investigated.

2.
NPJ Genom Med ; 8(1): 28, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37770509

RESUMEN

Elevated impulsivity is a key component of attention-deficit hyperactivity disorder (ADHD), bipolar disorder and juvenile myoclonic epilepsy (JME). We performed a genome-wide association, colocalization, polygenic risk score, and pathway analysis of impulsivity in JME (n = 381). Results were followed up with functional characterisation using a drosophila model. We identified genome-wide associated SNPs at 8q13.3 (P = 7.5 × 10-9) and 10p11.21 (P = 3.6 × 10-8). The 8q13.3 locus colocalizes with SLCO5A1 expression quantitative trait loci in cerebral cortex (P = 9.5 × 10-3). SLCO5A1 codes for an organic anion transporter and upregulates synapse assembly/organisation genes. Pathway analysis demonstrates 12.7-fold enrichment for presynaptic membrane assembly genes (P = 0.0005) and 14.3-fold enrichment for presynaptic organisation genes (P = 0.0005) including NLGN1 and PTPRD. RNAi knockdown of Oatp30B, the Drosophila polypeptide with the highest homology to SLCO5A1, causes over-reactive startling behaviour (P = 8.7 × 10-3) and increased seizure-like events (P = 6.8 × 10-7). Polygenic risk score for ADHD genetically correlates with impulsivity scores in JME (P = 1.60 × 10-3). SLCO5A1 loss-of-function represents an impulsivity and seizure mechanism. Synaptic assembly genes may inform the aetiology of impulsivity in health and disease.

3.
Epilepsy Behav ; 147: 109397, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37619460

RESUMEN

OBJECTIVE: Self-limiting Rolandic epilepsy (RE) is the most common epilepsy in school-age children. Seizures are generally infrequent, but cognitive, language, and motor coordination problems can significantly impact the child's life. To better understand brain structure and function changes in RE, we longitudinally assessed neurocognition, cortical thickness, and subcortical volumes. METHODS: At baseline, we recruited 30 participants diagnosed with RE and 24-healthy controls and followed up for 4.94 ± 0.8 years when the participants with RE were in seizure remission. Measures included were as follows: T1-weighted magnetic resonance brain imaging (MRI) with FreeSurfer analysis and detailed neuropsychological assessments. MRI and neuropsychological data were compared between baseline and follow-up in seizure remission. RESULTS: Longitudinal MRI revealed excess cortical thinning in the left-orbitofrontal (p = 0.0001) and pre-central gyrus (p = 0.044). There is a significant association (p = 0.003) between a reduction in cortical thickness in the left-orbitofrontal cluster and improved processing of filtered words. Longitudinal neuropsychology revealed significant improvements in the symptoms of developmental coordination disorder (DCD, p = 0.005) in seizure remission. CONCLUSIONS: There is evidence for altered development of neocortical regions between active seizure state and seizure remission in RE within two clusters maximal in the left-orbitofrontal and pre-central gyrus. There is significant evidence for improvement in motor coordination between active seizures and seizure remission and suggestive evidence for a decline in fluid intelligence and gains in auditory processing.


Asunto(s)
Epilepsia Rolándica , Niño , Humanos , Epilepsia Rolándica/diagnóstico por imagen , Estudios Prospectivos , Estudios Longitudinales , Convulsiones/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética
4.
Epilepsia Open ; 6(2): 310-322, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34033258

RESUMEN

OBJECTIVE: Recent neuroimaging studies have revealed differences in cortical and white matter brain structure in children with self-limiting rolandic epilepsy (RE). Despite this, reproducibility of the findings has been difficult, and there is no consensus about where and when structural differences are most apparent. We performed a systematic review of quantitative neuroimaging studies in children with RE to explore these questions. METHODS: Using PRISMA guidelines, we used a multilayered search strategy to identify neuroimaging studies in RE. Publications were included if they were quantitative and derived from controlled group studies and passed a quality assessment. Findings of the studies were presented and stratified by duration of epilepsy and age of participants. RESULTS: We identified six gray matter studies and five white matter studies. Consistent findings were found inside and outside the central sulcus, predominantly within the bilateral frontal and parietal lobes, striatal structures, such as the putamen and white matter, mainly involving the left superior longitudinal fasciculus and connections between the left pre- and postcentral gyrus. Stratification of the T1 studies by age found that cortical thickness differences varied between the under and over 10 year olds. Furthermore, the longer the duration of epilepsy, the less likely differences were detected. In white matter studies, there was a reduction in differences with increased age and duration of epilepsy. SIGNIFICANCE: These findings would suggest that the development of regions of the cortex in children with RE is abnormal. These regions are more widespread than the suspected seizure onset zone. Moreover, the findings would suggest that these differences are evidence of neurodevelopmental delay rather than apparent "damage" from the epilepsy.


Asunto(s)
Epilepsia Rolándica , Sustancia Blanca , Niño , Epilepsia Rolándica/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Sustancia Blanca/diagnóstico por imagen
5.
Ann Clin Transl Neurol ; 8(1): 138-152, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33264519

RESUMEN

OBJECTIVE: Impulsivity is a multidimensional construct that can predispose to psychopathology. Meta-analysis demonstrates an association between response impulsivity and Juvenile Myoclonic Epilepsy (JME), a common genetic generalized epilepsy. Here, we test the hypotheses that trait impulsivity is (i) elevated in JME compared to controls; (ii) moderated by specific seizure characteristics; and (iii) associated with psychiatric adverse effects of antiepileptic drugs (AEDs). METHODS: 322 participants with JME and 126 age and gender-matched controls completed the Barratt's Impulsiveness Scale (BIS-brief) alongside information on seizure history and AED use. We compared group BIS-brief scores and assessed associations of JME BIS-brief scores with seizure characteristics and AED adverse effects. RESULTS: The mean BIS-brief score in JME was 18.1 ± 4.4 compared with 16.2 ± 4.1 in controls (P = 0.0007). Elevated impulsivity was associated with male gender (P = 0.027), frequent absence seizures (P = 0.0004) and lack of morning predominance of myoclonus (P = 0.008). High impulsivity significantly increased the odds of a psychiatric adverse event on levetiracetam (P = 0.036), but not any other psychiatric or somatic adverse effects. INTERPRETATION: Trait impulsivity is elevated in JME and comparable to scores in personality and neurotic disorders. Increased seizure frequency and absence of circadian seizure pattern moderate BIS score, suggesting disruption of both cortico-striatal and thalamocortical networks as a shared mechanism between seizures and impulsivity in JME. These findings warrant consideration of impulsivity as a distinct target of intervention, and as a stratifying factor for AED treatment in JME, and perhaps other types of epilepsy. The role of impulsivity in treatment adherence and psychosocial outcome requires further investigation.


Asunto(s)
Conducta Impulsiva , Epilepsia Mioclónica Juvenil/psicología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven
6.
Arch Psychiatr Nurs ; 33(4): 364-370, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31280781

RESUMEN

This is a secondary data analysis exploring adherence to antiretroviral therapy (ART) in persons living with HIV (PLWH) with a comorbid mental health disorder. Logistic regression analyses indicated that PLWH who had reliable housing were over six times more adherent than those with unreliable housing. Descriptive odds ratio analyses showed directional relationships for ART adherence with coping, employment, and social support. These results indicate areas for future investigation in PLWH and comorbid mental health disorders, and the potential to find ways to foster certain emotional or living conditions that promote ART adherence.


Asunto(s)
Antirretrovirales/uso terapéutico , Comorbilidad , Infecciones por VIH/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Trastornos Mentales/tratamiento farmacológico , Adulto , Colorado , Femenino , Vivienda , Humanos , Masculino , Apoyo Social , Estrés Psicológico/psicología
7.
Front Psychol ; 9: 241, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29563887

RESUMEN

Background: Consolidation of learning occurs during sleep but when it is disturbed there may be an adverse impact upon these functions. While research has focused upon how sleep affects cognition in adulthood, the effects of disrupted sleep are likely to impact more heavily on learning among children and adolescents. We aimed to investigate whether a night's sleep impacts upon executive function compared with an equivalent wakefulness period. We also wanted to know whether restricting sleep would reduce these effects on performance. To investigate this issue in children, we adapted existing research methods to make them more suitable for this population. Methods: Using a cross-over trial design, 22 children aged 7-14 completed an updated but previously validated, continuous performance task (CPT) designed to be appealing to children, containing emotional and neutral targets and presented on an iPad. We measured omission and commission errors, mean and variability of reaction times (RTs) immediately and after a delay spent in the following three ways: 11-h intervals of unrestricted and restricted sleep in the style of a 'sleepover' and daytime wakefulness. We examined differences in immediate and delayed testing for each dependent variable. Both sleep nights were spent in a specialist sleep lab where polysomnography data were recorded. Results: While there were no significant main effects of sleep condition, as expected we observed significantly faster and more accurate performance in delayed compared with immediate testing across all conditions for omission errors, RT and variability of RT. Importantly, we saw a significant interaction for commission errors to emotional targets (p = 0.034): while they were comparable across all conditions during immediate testing, for delayed testing there were significantly more errors after wakefulness compared with unrestricted sleep (p = 0.019) and at a trend level for restricted sleep (p = 0.063). Performance improvement after restricted sleep was inversely correlated with sleep opportunity time (p = 0.03), total sleep time (p = 0.01) and total non-REM time (p = 0.005). Conclusion: This tool, designed to be simple to use and appealing to children, revealed a preserving effect of typical and disrupted sleep periods on performance during an emotionally themed target detection task compared with an equivalent wakefulness period.

8.
Eur Child Adolesc Psychiatry ; 27(7): 899-908, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29224173

RESUMEN

Current diagnostic systems conceptualise attention deficit hyperactivity disorder (ADHD), oppositional defiant/conduct disorder (ODD/CD) and autism spectrum disorder (ASD) as separate diagnoses. However, all three demonstrate executive functioning (EF) impairments. Whether these impairments are trans-diagnostic or disorder-specific remains relatively unexplored. Four groups of 10-16 year-olds [typically developing (TD; N = 43), individuals clinically diagnosed with ADHD (N = 21), ODD/CD (N = 26) and ASD (N = 41)] completed Go/NoGo and Switch tasks. Group differences were tested using analysis of co-variance (ANCOVA) including age, IQ, sex, conduct problems and ADHD symptoms as co-variates. Results indicated some disorder-specificity as only the ASD group demonstrated decreased probability of inhibition in the Go/NoGo task compared to all other groups. However, shared impairments were also found; all three diagnostic groups demonstrated increased reaction time variability (RTV) compared to the TD group, and both the ODD/CD and the ASD group demonstrated increased premature responses. When controlling for ADHD symptoms and conduct problems, group differences in RTV were no longer significant; however, the ASD group continued to demonstrate increased premature responses. No group differences were found in cognitive flexibility in the Switch task. A more varied response style was present across all clinical groups, although this appeared to be accounted for by sub-threshold ODD/CD and ADHD symptoms. Only the ASD group was impaired in response inhibition and premature responsiveness relative to TD adolescents. The findings suggest that some EF impairments typically associated with ADHD may also be found in individuals with ASD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Déficit de la Atención y Trastornos de Conducta Disruptiva/psicología , Trastorno del Espectro Autista/psicología , Función Ejecutiva/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino
9.
Epilepsy Behav ; 72: 135-139, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28575762

RESUMEN

Previous research shows that children with Rolandic Epilepsy have deficits of auditory processing. We wanted to confirm the nature of this deficit and whether it aggregates in families. We compared 40 children with Rolandic Epilepsy and 32 unaffected siblings with 99 typically developing children and 71 parents of RE children with 31 healthy adults on a battery of auditory processing tests. We also examined ear advantage in children with RE, their siblings and parents using population norms and measured non-word reading performance. We found a specific deficit for competing words in patients, their siblings and their parents, suggesting that this particular impairment of auditory processing present in children with RE, is heritable and likely to be persistent. Importantly, scores on this subtest in patients and siblings were significantly correlated with non-word reading performance. We saw increased rates of atypical left ear advantage in patients and siblings but no evidence of this in parents. We present these findings as evidence of familial incidence of dichotic listening and ear advantage abnormalities in relatives of children with Rolandic Epilepsy.


Asunto(s)
Trastornos de la Percepción Auditiva/diagnóstico , Pruebas de Audición Dicótica/métodos , Epilepsia Rolándica/diagnóstico , Padres , Hermanos , Adolescente , Adulto , Percepción Auditiva/fisiología , Trastornos de la Percepción Auditiva/epidemiología , Niño , Epilepsia Rolándica/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Epilepsia Open ; 2(2): 214-225, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-29588950

RESUMEN

Objective: Benign epilepsy with centrotemporal spikes (BECTS, also known as Rolandic epilepsy) is a common epilepsy syndrome that is associated with literacy and language impairments. The neural mechanisms of the syndrome are not known. The primary objective of this study was to test the hypothesis that functional connectivity within the language network is decreased in children with BECTS. We also tested the hypothesis that siblings of children with BECTS have similar abnormalities. Methods: Echo planar magnetic resonance (MR) imaging data were acquired from 25 children with BECTS, 12 siblings, and 20 healthy controls, at rest. After preprocessing with particular attention to intrascan motion, the mean signal was extracted from each of 90 regions of interest. Sparse, undirected graphs were constructed from adjacency matrices consisting of Spearman's rank correlation coefficients. Global and nodal graph metrics and subnetwork and pairwise connectivity were compared between groups. Results: There were no significant differences in graph metrics between groups. Children with BECTS had decreased functional connectivity relative to controls within a four-node subnetwork, which consisted of the left inferior frontal gyrus, the left superior frontal gyrus, the left supramarginal gyrus, and the right inferior parietal lobe (p = 0.04). A similar but nonsignificant decrease was also observed for the siblings. The BECTS groups had significant increases in connectivity within a five-node, five-edge frontal subnetwork. Significance: The results provide further evidence of decreased functional connectivity between key mediators of speech processing, language, and reading in children with BECTS. We hypothesize that these decreases reflect delayed lateralization of the language network and contribute to specific cognitive impairments.

11.
J Immunol ; 197(3): 726-35, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27324129

RESUMEN

Osteoimmunology arose from the recognition that cytokines produced by lymphocytes can affect bone homeostasis. We have previously shown that osteoclasts, cells that resorb bone, act as APCs. Cross-presentation of Ags by osteoclasts leads to expression of CD25 and Foxp3, markers of regulatory T cells in the CD8 T cells. Octeoclast-induced Foxp3(+) CD25(+) regulatory CD8 T cells (OC-iTcREG) suppress priming of CD4 and CD8 T cells by dendritic cells. OC-iTcREG also limit bone resorption by osteoclasts, forming a negative feedback loop. In this study, we show that OC-iTcREG express concurrently T-bet and Eomesodermin (Eomes) and IFN-γ. Pharmacological inhibition of IκK blocked IFN-γ, T-bet, and Eomes production by TcREG Furthermore, we show, using chromatin immunoprecipitation, NF-κB enrichment in the T-bet and Eomes promoters. We demonstrate that IFN-γ produced by TcREG is required for suppression of osteoclastogenesis and for degradation of TNFR-associated factor 6 in osteoclast precursors. The latter prevents signaling by receptor activator of NF-κB ligand needed for osteoclastogenesis. Knockout of IFN-γ rendered TcREG inefficient in preventing actin ring formation in osteoclasts, a process required for bone resorption. TcREG generated in vivo using IFN-γ(-/-) T cells had impaired ability to protect mice from bone resorption and bone loss in response to high-dose receptor activator of NF-κB ligand. The results of this study demonstrate a novel link between NF-κB signaling and induction of IFN-γ in TcREG and establish an important role for IFN-γ in TcREG-mediated protection from bone loss.


Asunto(s)
Células Presentadoras de Antígenos/inmunología , Resorción Ósea/inmunología , Linfocitos T CD8-positivos/inmunología , Interferón gamma/inmunología , Osteoclastos/inmunología , Animales , Presentación de Antígeno/inmunología , Western Blotting , Diferenciación Celular/inmunología , Inmunoprecipitación de Cromatina , Citometría de Flujo , Factores de Transcripción Forkhead/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/inmunología , FN-kappa B/metabolismo , Osteogénesis/fisiología , Reacción en Cadena de la Polimerasa , Transducción de Señal/inmunología , Proteínas de Dominio T Box/biosíntesis , Proteínas de Dominio T Box/inmunología
12.
Dev Med Child Neurol ; 57(11): 1019-26, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26219529

RESUMEN

AIM: Rolandic epilepsy is the most common childhood epilepsy, often presenting with neuropsychological impairments. The aim of the study was to formally assimilate the findings of existing studies varying widely in methodology, thereby confirming the nature and prevalence of impairments in literacy and language. METHODS: Using meta-analytical techniques, we evaluated 22 studies of literacy and/or language skills in children with rolandic epilepsy, published after 2000, among participants with IQs>70 and in which effect sizes could be acquired. Diagnosis required the presence of classical centrotemporal spikes arising from a normal background on electroencephalograms; a clinical history including at least one seizure; and no additional neurological condition. Overall effect size and heterogeneity were measured for single-word reading, phonological processing, and expressive and receptive language. RESULTS: Mean effect sizes (Cohen's d) ranged from 0.50 (95% confidence interval [CI] 0.23-0.78) for phonological processing, through 0.71 (95% CI 0.52-0.90) for word reading and 0.72 (95% CI 0.34-1.1) for receptive language, to 0.75 (95% CI 0.45-1.05) for expressive language. While group differences for reading measures were consistent, those for language were heterogeneous and varied across studies explained by age and IQ of samples. INTERPRETATION: The presence of reading and phonological processing deficits in children with rolandic epilepsy highlights the importance of early literacy and language assessment in this population.


Asunto(s)
Epilepsia Rolándica/complicaciones , Epilepsia Rolándica/diagnóstico , Trastornos del Desarrollo del Lenguaje/etiología , Alfabetización , Niño , Bases de Datos Bibliográficas/estadística & datos numéricos , Humanos , Lingüística
13.
Front Psychol ; 6: 602, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26029140

RESUMEN

Sleep disorders and sleep of insufficient duration and quality are on the increase due to changes in our lifestyle, particularly in children and adolescents. Sleep disruption is also more common in children with medical conditions, compounding their difficulties. Recent studies have focused on new mechanisms that explain how learning and cognitive performance depend on a good night's sleep. Growing alongside this latest understanding is an innovative new field of non-drug interventions that improve sleep architecture, with resulting cognitive improvements. However, we need to rigorously evaluate such potentially popular and self-administered sleep interventions with equally state-of-the-art outcome measurement tools. Animated hand-held games, that incorporate embedded sleep-dependent learning tasks, promise to offer new robust methods of measuring changes in overnight learning. Portable computing technology has the potential to offer practical, inexpensive and reliable tools to indirectly assess the quality of sleep. They may be adopted in both clinical and educational settings, providing a unique way of monitoring the effect of sleep disruption on learning, leading also to a radical rethink of how we manage chronic diseases.

14.
Am J Psychiatry ; 171(10): 1107-16, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24873905

RESUMEN

OBJECTIVE: Sustained attention problems are common in people with autism spectrum disorder (ASD) and may have significant implications for the diagnosis and management of ASD and associated comorbidities. Furthermore, ASD has been associated with atypical structural brain development. The authors used functional MRI to investigate the functional brain maturation of attention between childhood and adulthood in people with ASD. METHOD: Using a parametrically modulated sustained attention/vigilance task, the authors examined brain activation and its linear correlation with age between childhood and adulthood in 46 healthy male adolescents and adults (ages 11-35 years) with ASD and 44 age- and IQ-matched typically developing comparison subjects. RESULTS: Relative to the comparison group, the ASD group had significantly poorer task performance and significantly lower activation in inferior prefrontal cortical, medial prefrontal cortical, striato-thalamic, and lateral cerebellar regions. A conjunction analysis of this analysis with group differences in brain-age correlations showed that the comparison group, but not the ASD group, had significantly progressively increased activation with age in these regions between childhood and adulthood, suggesting abnormal functional brain maturation in ASD. Several regions that showed both abnormal activation and functional maturation were associated with poorer task performance and clinical measures of ASD and inattention. CONCLUSIONS: The results provide first evidence that abnormalities in sustained attention networks in individuals with ASD are associated with underlying abnormalities in the functional brain maturation of these networks between late childhood and adulthood.


Asunto(s)
Atención/fisiología , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiopatología , Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Cuerpo Estriado/fisiopatología , Corteza Prefrontal/fisiopatología , Tálamo/fisiopatología , Adolescente , Envejecimiento/fisiología , Mapeo Encefálico , Estudios de Casos y Controles , Cerebelo , Niño , Humanos , Imagen por Resonancia Magnética , Masculino , Desempeño Psicomotor/fisiología , Adulto Joven
15.
Biol Psychiatry ; 76(8): 616-28, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24314347

RESUMEN

BACKGROUND: Psychostimulant medication, most commonly the catecholamine agonist methylphenidate, is the most effective treatment for attention-deficit/hyperactivity disorder (ADHD). However, relatively little is known on the mechanisms of action. Acute effects on brain function can elucidate underlying neurocognitive effects. We tested methylphenidate effects relative to placebo in functional magnetic resonance imaging (fMRI) during three disorder-relevant tasks in medication-naïve ADHD adolescents. In addition, we conducted a systematic review and meta-analysis of the fMRI findings of acute stimulant effects on ADHD brain function. METHODS: The fMRI study compared 20 adolescents with ADHD under either placebo or methylphenidate in a randomized controlled trial while performing stop, working memory, and time discrimination tasks. The meta-analysis was conducted searching PubMed, ScienceDirect, Web of Knowledge, Google Scholar, and Scopus databases. Peak coordinates of clusters of significant effects of stimulant medication relative to placebo or off medication were extracted for each study. RESULTS: The fMRI analysis showed that methylphenidate significantly enhanced activation in bilateral inferior frontal cortex (IFC)/insula during inhibition and time discrimination but had no effect on working memory networks. The meta-analysis, including 14 fMRI datasets and 212 children with ADHD, showed that stimulants most consistently enhanced right IFC/insula activation, which also remained for a subgroup analysis of methylphenidate effects alone. A more lenient threshold also revealed increased putamen activation. CONCLUSIONS: Psychostimulants most consistently increase right IFC/insula activation, which are key areas of cognitive control and also the most replicated neurocognitive dysfunction in ADHD. These neurocognitive effects may underlie their positive clinical effects.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/terapia , Encéfalo , Estimulación Encefálica Profunda/métodos , Adolescente , Encéfalo/irrigación sanguínea , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inhibición Psicológica , Imagen por Resonancia Magnética , Masculino , Metaanálisis como Asunto , Metilfenidato/uso terapéutico , Pruebas Neuropsicológicas , Oxígeno/sangre , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Cereb Cortex ; 24(1): 174-85, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23048018

RESUMEN

The stimulant methylphenidate (MPX) and the nonstimulant atomoxetine (ATX) are the most commonly prescribed medications for attention deficit hyperactivity disorder (ADHD). However, no functional magnetic resonance imaging (fMRI) study has as yet investigated the effects of ATX on inhibitory or any other brain function in ADHD patients or compared its effects with those of MPX. A randomized, double-blind, placebo-controlled, crossover pharmacological design was used to compare the neurofunctional effects of single doses of MPX, ATX, and placebo during a stop task, combined with fMRI within 19 medication-naive ADHD boys, and their potential normalization effects relative to 29 age-matched healthy boys. Compared with controls, ADHD boys under placebo showed bilateral ventrolateral prefrontal, middle temporal, and cerebellar underactivation. Within patients, MPX relative to ATX and placebo significantly upregulated right ventrolateral prefrontal activation, which correlated with enhanced inhibitory capacity. Relative to controls, both drugs significantly normalized the left ventrolateral prefrontal underactivation observed under placebo, while MPX had a drug-specific effect of normalizing right ventrolateral prefrontal and cerebellar underactivation observed under both placebo and ATX. The findings show shared and drug-specific effects of MPX and ATX on performance and brain activation during inhibitory control in ADHD patients with superior upregulation and normalization effects of MPX.


Asunto(s)
Inhibidores de Captación Adrenérgica/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/psicología , Encéfalo/fisiopatología , Estimulantes del Sistema Nervioso Central/uso terapéutico , Inhibición Psicológica , Metilfenidato/uso terapéutico , Propilaminas/uso terapéutico , Adolescente , Análisis de Varianza , Clorhidrato de Atomoxetina , Encéfalo/efectos de los fármacos , Estudios de Casos y Controles , Catecolaminas/metabolismo , Niño , Estudios Cruzados , Interpretación Estadística de Datos , Método Doble Ciego , Humanos , Procesamiento de Imagen Asistido por Computador , Pruebas de Inteligencia , Imagen por Resonancia Magnética , Masculino , Movimiento/fisiología , Pruebas Neuropsicológicas , Corteza Prefrontal/fisiopatología , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología
17.
Hum Brain Mapp ; 35(7): 3083-94, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24123508

RESUMEN

The diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) is based on subjective measures despite evidence for multisystemic structural and functional deficits. ADHD patients have consistent neurofunctional deficits in motor response inhibition. The aim of this study was to apply pattern classification to task-based functional magnetic resonance imaging (fMRI) of inhibition, to accurately predict the diagnostic status of ADHD. Thirty adolescent ADHD and thirty age-matched healthy boys underwent fMRI while performing a Stop task. fMRI data were analyzed with Gaussian process classifiers (GPC), a machine learning approach, to predict individual ADHD diagnosis based on task-based activation patterns. Traditional univariate case-control analyses were also performed to replicate previous findings in a relatively large dataset. The pattern of brain activation correctly classified up to 90% of patients and 63% of controls, achieving an overall classification accuracy of 77%. The regions of the discriminative network most predictive of controls included later developing lateral prefrontal, striatal, and temporo-parietal areas that mediate inhibition, while regions most predictive of ADHD were in earlier developing ventromedial fronto-limbic regions, which furthermore correlated with symptom severity. Univariate analysis showed reduced activation in ADHD in bilateral ventrolateral prefrontal, striatal, and temporo-parietal regions that overlapped with areas predictive of controls, suggesting the latter are dysfunctional areas in ADHD. We show that significant individual classification of ADHD patients of 77% can be achieved using whole brain pattern analysis of task-based fMRI inhibition data, suggesting that multivariate pattern recognition analyses of inhibition networks can provide objective diagnostic neuroimaging biomarkers of ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/psicología , Encéfalo/fisiopatología , Inhibición Psicológica , Enfermedades del Sistema Nervioso/etiología , Adolescente , Análisis de Varianza , Encéfalo/irrigación sanguínea , Niño , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Distribución Normal , Oxígeno/sangre , Tiempo de Reacción
18.
PLoS One ; 8(5): e63660, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23696841

RESUMEN

OBJECTIVE: Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder, but diagnosed by subjective clinical and rating measures. The study's aim was to apply Gaussian process classification (GPC) to grey matter (GM) volumetric data, to assess whether individual ADHD adolescents can be accurately differentiated from healthy controls based on objective, brain structure measures and whether this is disorder-specific relative to autism spectrum disorder (ASD). METHOD: Twenty-nine adolescent ADHD boys and 29 age-matched healthy and 19 boys with ASD were scanned. GPC was applied to make disorder-specific predictions of ADHD diagnostic status based on individual brain structure patterns. In addition, voxel-based morphometry (VBM) analysis tested for traditional univariate group level differences in GM. RESULTS: The pattern of GM correctly classified 75.9% of patients and 82.8% of controls, achieving an overall classification accuracy of 79.3%. Furthermore, classification was disorder-specific relative to ASD. The discriminating GM patterns showed higher classification weights for ADHD in earlier developing ventrolateral/premotor fronto-temporo-limbic and stronger classification weights for healthy controls in later developing dorsolateral fronto-striato-parieto-cerebellar networks. Several regions were also decreased in GM in ADHD relative to healthy controls in the univariate VBM analysis, suggesting they are GM deficit areas. CONCLUSIONS: The study provides evidence that pattern recognition analysis can provide significant individual diagnostic classification of ADHD patients and healthy controls based on distributed GM patterns with 79.3% accuracy and that this is disorder-specific relative to ASD. Findings are a promising first step towards finding an objective differential diagnostic tool based on brain imaging measures to aid with the subjective clinical diagnosis of ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno Autístico/diagnóstico , Imagen por Resonancia Magnética/métodos , Adolescente , Mapeo Encefálico , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Patrones de Reconocimiento Fisiológico/fisiología
19.
Epilepsia ; 53(4): 705-11, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22220688

RESUMEN

PURPOSE: Children with rolandic epilepsy (RE) experience difficulties with reading, language, and attention. Their siblings are at high risk of dyslexia but are not otherwise known to have neurocognitive deficits. We therefore sought evidence for an RE-associated neurocognitive endophenotype. METHODS: Thirteen probands (male-to-female ratio 9:4) and 11 epilepsy-free siblings (male-to-female ratio 5:6) completed a neurocognitive evaluation within the domains of reading, language, and attention. Frequencies of impairment were compared, and mean standardized scores of children with RE and their siblings were each compared against population means. KEY FINDINGS: Frequency of impairment in each domain was comparable for siblings and probands: 9% of siblings and 31% of probands were reading impaired; 36% of siblings and 54% of probands were language impaired; and 70% of siblings and 67% of probands had attention impairments. Comparison of differences between sample and population means revealed evidence of a similar pattern of language deficits in both groups, specifically for picture naming and attention to competing words. For measures of attention, both groups made significantly higher omission errors and were impaired in their ability to sustain attention. SIGNIFICANCE: Children with RE and unaffected siblings demonstrate neurocognitive impairments in the domains of language and attention that are likely to remain undetected with general clinical protocols. Neurocognitively impaired probands and siblings showed a remarkably similar profile of deficits in language and attention that could explain poor academic performance. Early evaluation and intervention may benefit these children academically.


Asunto(s)
Trastornos del Conocimiento/etiología , Discapacidades del Desarrollo/etiología , Endofenotipos , Epilepsia Rolándica/complicaciones , Adolescente , Niño , Trastornos del Conocimiento/genética , Epilepsia Rolándica/genética , Salud de la Familia , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas
20.
Front Hum Neurosci ; 5: 136, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22087089

RESUMEN

Compared to our understanding of the functional maturation of executive functions, little is known about the neurofunctional development of perceptive functions. Time perception develops during late adolescence, underpinning many functions including motor and verbal processing, as well as late maturing higher order cognitive skills such as forward planning and future-related decision making. Nothing, however, is known about the neurofunctional changes associated with time perception from childhood to adulthood. Using functional magnetic resonance imaging we explored the effects of age on the brain activation and functional connectivity of 32 male participants from 10 to 53 years of age during a time discrimination task that required the discrimination of temporal intervals of seconds differing by several hundred milliseconds. Increasing development was associated with progressive activation increases within left lateralized dorsolateral and inferior fronto-parieto-striato-thalamic brain regions. Furthermore, despite comparable task performance, adults showed increased functional connectivity between inferior/dorsolateral interhemispheric fronto-frontal activation as well as between inferior fronto-parietal regions compared with adolescents. Activation in caudate, specifically, was associated with both increasing age and better temporal discrimination. Progressive decreases in activation with age were observed in ventromedial prefrontal cortex, limbic regions, and cerebellum. The findings demonstrate age-dependent developmentally dissociated neural networks for time discrimination. With increasing age there is progressive recruitment of later maturing left hemispheric and lateralized fronto-parieto-striato-thalamic networks, known to mediate time discrimination in adults, while earlier developing brain regions such as ventromedial prefrontal cortex, limbic and paralimbic areas, and cerebellum subserve fine-temporal processing functions in children and adolescents.

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