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1.
Eur J Paediatr Neurol ; 51: 93-99, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38905883

RESUMO

PURPOSE: Attentional and executive dysfunctions are the most frequent cognitive disorders in neurofibromatosis type 1 (NF1), with a high prevalence of attention deficit-hyperactivity disorder (ADHD). We (i) compared attentional profiles between NF1 children with and without ADHD and children with primary ADHD criteria and (ii) investigated the possible relationship between attentional disorders and "unidentified bright objects" (UBOs) in NF1. METHODS: This retrospective study included 47 NF1 children, 25 with ADHD criteria (NF1+adhd group), matched for age, sex, and cognitive level with 47 children with primary ADHD (ADHD group). We collected computer task (sustained-attention, visuomotor-decision, inhibition, and cognitive-flexibility tasks) scores normalized for age and sex, and brain magnetic resonance imaging data. RESULTS: (i) Working memory was impaired in all groups. (ii) Omissions (p < 0.002) and response-time variability (p < 0.05) in sustained-attention and visuomotor-decision tasks and errors (p < 0.02) in the cognitive-flexibility task were lower for the NFI+adhd and ADHD groups than for the NF1-no-adhd group. (iii) The NF1+adhd group had slower response times (p ≤ 0.02) for inhibition and visuomotor-decision tasks than the other groups. (iv) We found no relevant association between cognitive performance and UBOs. CONCLUSIONS: NF1 children with ADHD have an attentional and executive functions deficit profile similar to that of children with primary ADHD, but with a slower response-time, increasing learning difficulties. The atypical connectivity of fronto-striatal pathways, poorer dopamine homeostasis, and increased GABA inhibition observed in NF1 renders vulnerable the development of the widely distributed neural networks that support attentional, working-memory, and executive functions.

2.
Epilepsia Open ; 9(2): 582-591, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38173190

RESUMO

BACKGROUND: Attention-deficit hyperactivity disorder (ADHD) is a frequent comorbidity in children with epilepsy, which management mostly relies on the usual treatments of ADHD, especially methylphenidate. Supplementation with polyunsaturated n-3 Fatty Acid (PUFA) has been proposed as an alternative therapeutic approach in ADHD without epilepsy but has never been evaluated in epilepsy-associated ADHD. METHODS: A multicenter double blind randomized placebo-controlled trial evaluating supplementation with PUFA, in eicosapentaenoic- and docosahexaenoic-acid form, conjugated to a phospholipid vector (PS-Omega3) in children aged >6 and <16-years old, and suffering from any type of epilepsy and ADHD (inattentive or combined type) according to DSM-V. After a 4-week baseline period, patients were allocated (1:1) either to placebo group or to PS-Omega 3 group and entered a 12 week-double-blind treatment period which was followed by a 12 week-open-label treatment period. The primary outcome was the reduction of the ADHD-rating scale IV attention-deficit subscore after 12 weeks of treatment. RESULTS: The study was stopped early because of lack of eligible participants and the expected sample size was not reached. Seventy-four patients were randomized, 44 in PS-Omega3, and 30 in the placebo group. The reduction after 12 weeks of treatment in the inattention subscore of the ADHD-IV scale was -1.57 in the PS-Omega3 group, and -2.90 in the placebo group (p = 0.33, α = 5%). Results were similar after 24 weeks of treatment and for all other ADHD-related secondary outcomes, with no difference between placebo and PS-Omega3. CONCLUSION: Our study remaining underpowered, no formal conclusion about the effect of Ps-Omega3 could be drawn. However, our data strongly suggested that the PS-Omega 3 formulation used in the current study did not improve ADHD symptoms in children with epilepsy. PLAIN LANGUAGE SUMMARY: Supplementation with polyunsaturated n-3 Fatty Acid (PUFA) has been proposed in ADHD but has never been evaluated in patients with both epilepsy and ADHD. To address this issue, we conducted a multicenter double blind randomized placebo-controlled trial evaluating supplementation with PUFA in children with epilepsy and ADHD. The study was stopped early because of lack of eligible participants, hampering formal conclusion. However, the evolution of the ADHD symptoms at 12 and 24 weeks did not differ between placebo and PUFA supplementation, strongly suggesting that PUFA did not improve ADHD symptoms in children with epilepsy.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Epilepsia , Ácidos Graxos Ômega-3 , Criança , Humanos , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Fosfatidilserinas/uso terapêutico , Resultado do Tratamento , Ácidos Graxos Ômega-3/uso terapêutico , Ácidos Graxos Insaturados/uso terapêutico , Epilepsia/tratamento farmacológico , Suplementos Nutricionais
3.
Seizure ; 110: 78-85, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37331197

RESUMO

PURPOSE: This retrospective chart review study (GWEP20052) evaluated plant-derived highly purified cannabidiol (CBD; Epidyolex®; 100 mg/mL oral solution) use without clobazam as add-on therapy in patients aged ≥2 years with Lennox-Gastaut syndrome (LGS) or Dravet syndrome (DS) enrolled in a European Early Access Program. METHODS: Data were extracted from patient charts covering a period starting 3 months before CBD treatment and concluding after 12 months of CBD treatment, or sooner if a patient discontinued CBD or started clobazam. RESULTS: Of 114 enrolled patients, data were available for 107 (92 LGS, 15 DS) who received CBD without clobazam for ≥3 months. Mean age: 14.5 (LGS) and 10.5 (DS) years; female: 44% (LGS) and 67% (DS). Mean time-averaged CBD dose: 13.54 (LGS) and 11.56 (DS) mg/kg/day. Median change from baseline in seizure frequency per 28 days over 3-month intervals varied from -6.2% to -20.9% for LGS and 0% to -16.7% for DS. Achievement of ≥50% reduction in drop (LGS) or convulsive (DS) seizures at 3 and 12 months: LGS, 19% (n = 69) and 30% (n = 53); DS, 21% (n = 14) and 13% (n = 8). Retention on CBD without clobazam (enrolled set): 94%, 80%, 69%, and 63% at 3, 6, 9, and 12 months. Adverse event (AE) incidence was 31%, most commonly somnolence, seizure, diarrhea, and decreased appetite. Two patients discontinued CBD owing to AEs, and four patients with LGS experienced elevated liver enzymes. CONCLUSION: Results support favorable effectiveness and retention of CBD without concomitant clobazam for up to 12 months in clinical practice.


Assuntos
Canabidiol , Epilepsias Mioclônicas , Síndrome de Lennox-Gastaut , Humanos , Adolescente , Canabidiol/uso terapêutico , Síndrome de Lennox-Gastaut/tratamento farmacológico , Clobazam/uso terapêutico , Estudos Retrospectivos , Anticonvulsivantes/uso terapêutico , Epilepsias Mioclônicas/tratamento farmacológico , Convulsões/tratamento farmacológico , Convulsões/induzido quimicamente , Resultado do Tratamento
4.
Plant Methods ; 19(1): 31, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991448

RESUMO

BACKGROUND: Even for easy-to-transform species or genotypes, the creation of transgenic or edited plant lines remains a significant bottleneck. Thus, any technical advance that accelerates the regeneration and transformation process is welcome. So far, methods to produce Brachypodium distachyon (Bd) transgenics span at least 14 weeks from the start of tissue culture to the recovery of regenerated plantlets. RESULTS: We have previously shown that embryogenic somatic tissues grow in the scutellum of immature zygotic Bd embryos within 3 days of in vitro induction with exogenous auxin and that the development of secondary embryos can be initiated immediately thereafter. Here, we further demonstrate that such pluripotent reactive tissues can be genetically transformed with Agrobacterium tumefaciens right after the onset of somatic embryogenesis. In brief, immature zygotic embryos are induced for callogenesis for one week, co-cultured with Agrobacterium for three days, then incubated on callogenesis selective medium for three weeks, and finally transferred on selective regeneration medium for up to three weeks to obtain plantlets ready for rooting. This 7-to-8-week procedure requires only three subcultures. Its validation includes the molecular and phenotype characterization of Bd lines carrying transgenic cassettes and novel CRISPR/Cas9-generated mutations in two independent loci coding for nitrate reductase enzymes (BdNR1 and BdNR2). CONCLUSIONS: With a short callogenesis stage and streamlined in vitro regeneration following co-cultivation with Agrobacterium, transgenic and edited T0 Bd plantlets can be produced in about 8 weeks, a gain of one to two months compared to previously published methods, with no reduction in transformation efficiency and at lower costs.

5.
J Med Genet ; 60(6): 578-586, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36319078

RESUMO

PURPOSE: In this study, we describe the phenotype and genotype of the largest cohort of patients with Joubert syndrome (JS) carrying pathogenic variants on one of the most frequent causative genes, CC2D2A. METHODS: We selected 53 patients with pathogenic variants on CC2D2A, compiled and analysed their clinical, neuroimaging and genetic information and compared it to previous literature. RESULTS: Developmental delay (motor and language) was nearly constant but patients had normal intellectual efficiency in 74% of cases (20/27 patients) and 68% followed mainstream schooling despite learning difficulties. Epilepsy was found in only 13% of cases. Only three patients had kidney cysts, only three had genuine retinal dystrophy and no subject had liver fibrosis or polydactyly. Brain MRIs showed typical signs of JS with rare additional features. Genotype-phenotype correlation findings demonstrate a homozygous truncating variant p.Arg950* linked to a more severe phenotype. CONCLUSION: This study contradicts previous literature stating an association between CC2D2A-related JS and ventriculomegaly. Our study implies that CC2D2A-related JS is linked to positive neurodevelopmental outcome and low rate of other organ defects except for homozygous pathogenic variant p.Arg950*. This information will help modulate patient follow-up and provide families with accurate genetic counselling.


Assuntos
Anormalidades Múltiplas , Anormalidades do Olho , Doenças Renais Císticas , Humanos , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/genética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Anormalidades do Olho/diagnóstico , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Retina/diagnóstico por imagem , Retina/patologia , Proteínas do Citoesqueleto
6.
Epilepsy Behav ; 126: 108471, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915430

RESUMO

AIM: KCNB1 encephalopathy encompasses a broad phenotypic spectrum associating intellectual disability, behavioral disturbances, and epilepsies of various severity. Using standardized parental questionnaires, we aimed to capture the heterogeneity of the adaptive and behavioral features in a series of patients with KCNB1 pathogenic variants. METHODS: We included 25 patients with a KCNB1 encephalopathy, aged from 3.2 to 34.1 years (median = 10 years). Adaptive functioning was assessed in all patients using the French version of the Vineland Adaptive Behavior Scales, Second Edition (VABS-II) questionnaire. We screened global behavior with the Childhood Behavioral Check-List (CBCL, Achenbach) and autism spectrum disorder (ASD) with the Social Communication Questionnaire (SCQ). We used a cluster analysis to identify subgroups of adaptive profiles. RESULTS: VABS-II questionnaire showed pathological adaptive behavior in all participants with a severity of adaptive deficiency ranging from mild in 8/20 to severe in 7/20. Eight out of 16 were at risk of Attention Problems at the CBCL and 13/18 were at risk of autism spectrum disorder (ASD). The adaptive behavior composite score significantly decreased with age (Spearman's Rho=-0.72, p<0.001) but not the equivalent ages, suggesting stagnation and slowing but no regression over time. The clustering analysis identified two subgroups of patients, one showing more severe adaptive behavior. The severity of the epilepsy phenotype predicted the severity of the behavioral profile with a sensitivity of 70% and a specificity of 90.9%. CONCLUSION: This study confirms the deleterious consequences of early-onset epilepsy in addition to the impact of the gene dysfunction in patients with KCNB1 encephalopathy. ASD and attention disorders are frequent. Parental questionnaires should be considered as useful tools for early screening and care adaptation.


Assuntos
Transtorno do Espectro Autista , Encefalopatias , Epilepsia , Deficiência Intelectual , Adaptação Psicológica , Adolescente , Adulto , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/genética , Encefalopatias/complicações , Encefalopatias/epidemiologia , Encefalopatias/genética , Criança , Pré-Escolar , Epilepsia/genética , Humanos , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Deficiência Intelectual/psicologia , Canais de Potássio Shab/genética , Adulto Jovem
7.
Neonatology ; 119(1): 124-128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34879383

RESUMO

BACKGROUND: Overall and respiratory management of preterm children are constantly evolving, which might have changed both the pathophysiology and neurodevelopmental consequences of bronchopulmonary dysplasia (BPD). OBJECTIVES: The objective of this study is to determine whether the previously shown association between BPD and risk of developmental delay persists. METHODS: The study population was children born before 32 weeks' gestation from the French prospective cohort EPIPAGE-2. The exposure was BPD assessed at 36 weeks' postmenstrual age. The main outcome was risk of developmental delay defined by an Age & Stages Questionnaires (ASQ) score below threshold at 24 months' corrected age. RESULTS: The analyzed population included 2,706 children. Among those with available ASQ score, 196/1,587 had BPD and 671/1,587 had an ASQ score below threshold. BPD was associated with an ASQ score below threshold (odds ratio 1.52, 95% confidence interval 1.11-2.08; p = 0.008). CONCLUSIONS: BPD was strongly associated with risk of developmental delay.


Assuntos
Displasia Broncopulmonar , Displasia Broncopulmonar/complicações , Criança , Pré-Escolar , Estudos de Coortes , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estudos Prospectivos
8.
Neurophysiol Clin ; 50(5): 383-386, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33172760

RESUMO

We report on a 7-year-old female who presented paroxysmal episodes of loss of consciousness with clonic movements. The electroencephalogram (EEG) evidenced diffuse slow wave activations, with no symptoms. Epilepsy was suspected but antiepileptic drugs were ineffective. Video-EEG monitoring revealed that the syncope was triggered by stretching with a tachycardia that started during the stretch maneuver and diffuse slow waves on the EEG 2s before the symptoms. Stretch syncope can result in striking manifestations with subcortically driven clonic movements that can be mistaken for signs of epilepsy. Stretching might lead to transient hypoxia of the brainstem; in turn, this might activate the thalamocortical loop and thus generate cardiovascular changes, EEG slow waves, and physical manifestations.


Assuntos
Epilepsia , Convulsões , Criança , Diagnóstico Diferencial , Eletroencefalografia , Epilepsia/diagnóstico , Feminino , Humanos , Convulsões/diagnóstico , Síncope/diagnóstico
9.
Epilepsia ; 61(11): 2461-2473, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32954514

RESUMO

OBJECTIVE: We aimed to delineate the phenotypic spectrum and long-term outcome of individuals with KCNB1 encephalopathy. METHODS: We collected genetic, clinical, electroencephalographic, and imaging data of individuals with KCNB1 pathogenic variants recruited through an international collaboration, with the support of the family association "KCNB1 France." Patients were classified as having developmental and epileptic encephalopathy (DEE) or developmental encephalopathy (DE). In addition, we reviewed published cases and provided the long-term outcome in patients older than 12 years from our series and from literature. RESULTS: Our series included 36 patients (21 males, median age = 10 years, range = 1.6 months-34 years). Twenty patients (56%) had DEE with infantile onset seizures (seizure onset = 10 months, range = 10 days-3.5 years), whereas 16 (33%) had DE with late onset epilepsy in 10 (seizure onset = 5 years, range = 18 months-25 years) and without epilepsy in six. Cognitive impairment was more severe in individuals with DEE compared to those with DE. Analysis of 73 individuals with KCNB1 pathogenic variants (36 from our series and 37 published individuals in nine reports) showed developmental delay in all with severe to profound intellectual disability in 67% (n = 41/61) and autistic features in 56% (n = 32/57). Long-term outcome in 22 individuals older than 12 years (14 in our series and eight published individuals) showed poor cognitive, psychiatric, and behavioral outcome. Epilepsy course was variable. Missense variants were associated with more frequent and more severe epilepsy compared to truncating variants. SIGNIFICANCE: Our study describes the phenotypic spectrum of KCNB1 encephalopathy, which varies from severe DEE to DE with or without epilepsy. Although cognitive impairment is worse in patients with DEE, long-term outcome is poor for most and missense variants are associated with more severe epilepsy outcome. Further understanding of disease mechanisms should facilitate the development of targeted therapies, much needed to improve the neurodevelopmental prognosis.


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/genética , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Variação Genética/genética , Canais de Potássio Shab/genética , Adolescente , Adulto , Encefalopatias/fisiopatologia , Criança , Pré-Escolar , Estudos de Coortes , Eletroencefalografia/tendências , Epilepsia/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
10.
Hum Mutat ; 41(1): 69-80, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513310

RESUMO

Developmental and epileptic encephalopathies (DEE) refer to a heterogeneous group of devastating neurodevelopmental disorders. Variants in KCNB1 have been recently reported in patients with early-onset DEE. KCNB1 encodes the α subunit of the delayed rectifier voltage-dependent potassium channel Kv 2.1. We review the 37 previously reported patients carrying 29 distinct KCNB1 variants and significantly expand the mutational spectrum describing 18 novel variants from 27 unreported patients. Most variants occur de novo and mainly consist of missense variants located on the voltage sensor and the pore domain of Kv 2.1. We also report the first inherited variant (p.Arg583*). KCNB1-related encephalopathies encompass a wide spectrum of neurodevelopmental disorders with predominant language difficulties and behavioral impairment. Eighty-five percent of patients developed epilepsies with variable syndromes and prognosis. Truncating variants in the C-terminal domain are associated with a less-severe epileptic phenotype. Overall, this report provides an up-to-date review of the mutational and clinical spectrum of KCNB1, strengthening its place as a causal gene in DEEs and emphasizing the need for further functional studies to unravel the underlying mechanisms.


Assuntos
Epilepsia/diagnóstico , Epilepsia/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Canais de Potássio Shab/genética , Alelos , Estudos de Associação Genética/métodos , Genótipo , Humanos , Fenótipo , Canais de Potássio Shab/química , Canais de Potássio Shab/metabolismo , Relação Estrutura-Atividade
11.
Eur Child Adolesc Psychiatry ; 27(3): 377-384, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28993963

RESUMO

OBJECTIVE: Clinical trials and inconclusive meta-analyses have investigated the effects of omega-3 supplements in children with Attention-Deficit Hyperactivity Disorder (ADHD). We performed a randomised placebo-controlled trial to evaluate the efficacy of omega-3 fatty acids. METHODS: Children aged 6-15 years with established diagnosis of ADHD were randomised 1:1 to receive either supplements containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) or a placebo for 3 months. Psychotropic or omega-3-containing treatments were not authorised during the study. The primary outcome was the change in the Attention-Deficit Hyperactivity Disorder Rating Scale version 4 (ADHD-RS-IV). Other outcomes included safety, lexical level (Alouette test), attention (Test of Attentional Performance for Children-KiTAP), anxiety (48-item Conners Parent Rating Scale-Revised-CPRS-R), and depression (Children's Depression Inventory-CDI). RESULTS: Between 2009 and 2011, 162 children were included in five French child psychiatry centres. The mean age was 9.90 (SD 2.62) years and 78.4% were boys. The inclusion ADHD-RS-IV at was 37.31 (SD 8.40). The total ADHD-RS-IV score reduction was greater in the placebo group than in the DHA-EPA group: -19 (-26, -12)  % and -9.7 (-16.6, -2.9) %, respectively, p = 0.039. The other components of the Conners score had a similar variation but the differences between groups were not significant. Two patients in the DHA-EPA group and none in the placebo group experienced a severe adverse event (hospitalisation for worsening ADHD symptoms). CONCLUSION: This study did not show any beneficial effect of omega-3 supplement in children with mild ADHD symptoms.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Ácidos Graxos Ômega-3/uso terapêutico , Adolescente , Criança , Método Duplo-Cego , Ácidos Graxos Ômega-3/farmacologia , Feminino , Humanos , Masculino , Resultado do Tratamento
12.
Neuroimage Clin ; 15: 359-366, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28580292

RESUMO

Although infantile spasms can be caused by a variety of etiologies, the clinical features are stereotypical. The neuronal and vascular mechanisms that contribute to the emergence of infantile spasms are not well understood. We performed a multimodal study by simultaneously recording electroencephalogram and functional Near-infrared spectroscopy in an intentionally heterogeneous population of six children with spasms in clusters. Regardless of the etiology, spasms were accompanied by two phases of hemodynamic changes; an initial change in the cerebral blood volume (simultaneously with each spasm) followed by a neurovascular coupling in all children except for the one with a large porencephalic cyst. Changes in cerebral blood volume, like the neurovascular coupling, occurred over frontal areas in all patients regardless of any brain damage suggesting a diffuse hemodynamic cortical response. The simultaneous motor activation and changes in cerebral blood volume might result from the involvement of the brainstem. The inconstant neurovascular coupling phase suggests a diffuse activation of the brain likely resulting too from the brainstem involvement that might trigger diffuse changes in cortical excitability.


Assuntos
Córtex Cerebral/fisiopatologia , Eletroencefalografia/métodos , Acoplamento Neurovascular/fisiologia , Espasmos Infantis/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Córtex Cerebral/diagnóstico por imagem , Eletromiografia , Feminino , Humanos , Lactente , Masculino , Imagem Multimodal , Espasmos Infantis/diagnóstico por imagem
13.
Front Neurosci ; 11: 59, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28239337

RESUMO

Objective: High Density electroencephalography (HD EEG) is the reference non-invasive technique to investigate the dynamics of neuronal networks in Benign Epilepsy with Centro-Temporal Spikes (BECTS). Analysis of local dynamic changes surrounding Interictal Epileptic Spikes (IES) might improve our knowledge of the mechanisms that propel neurons to the hypersynchronization of IES in BECTS. Transient distant changes in the dynamics of neurons populations may also interact with neuronal networks involved in various functions that are impaired in BECTS patients. Methods: HD EEG (64 electrodes) of eight well-characterized BECTS patients (8 males; mean age: 7.2 years, range: 5-9 years) were analyzed. Unilateral IES were selected in 6 patients. They were bilateral and independent in 2 other patients. This resulted in a total of 10 groups of IES. Time-frequency analysis was performed on HD EEG epochs around the peak of the IES (±1000 ms), including phase-locked and non-phase-locked activities to the IES. The time frequency analyses were calculated for the frequencies between 4 and 200 Hz. Results: Time-frequency analysis revealed two patterns of dysregulation of the synchronization between neuronal networks preceding and following hypersynchronization of interictal spikes (±400 ms) in the epileptogenic zone. Dysregulation consists of either desynchronization (n = 6) or oscillating synchronization (n = 4) (4-50 Hz) surrounding the IES. The 2 patients with bilateral IES exhibited only local desynchronization whatever the IES considered. Distant desynchronization in low frequencies within the same window occurs simultaneously in bilateral frontal, temporal and occipital areas (n = 7). Significance: Using time-frequency analysis of HD EEG data in a well-defined population of BECTS, we demonstrated repeated complex changes in the dynamics of neuronal networks not only during, but also, before and after the IES. In the epileptogenic zone, our results found more complex reorganization of the local network than initially thought. In line with previous results obtained at a microscopic or macroscopic level, these changes suggested the variability strategies of neuronal assemblies to raise IES. Distant changes from the epileptogenic zone in desynchronization observed in the same time window suggested interactions between larger embedded networks and opened new avenues about their possible role in the underlying mechanism leading to cognitive deficits.

14.
J Atten Disord ; 21(14): 1208-1220, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24420764

RESUMO

OBJECTIVE: A failure of the anti-phase synchronization between default-mode (DMN) and task-positive networks (TPN) may be involved in a main manifestation of ADHD: moment-to-moment variability. The study investigated whereby methylphenidate may improve TPN/DMN synchronization in ADHD. METHOD: Eleven drug-naive ADHD children and 11 typically developing (TD) children performed a flanker task during functional magnetic resonance imaging. The ADHD group was scanned without and 1 month later with methylphenidate. The signal was analyzed by independent component analysis. RESULTS: The TD group showed anti-phase DMN/TPN synchronization. The unmedicated ADHD group showed synchronous activity in the posterior DMN only, which was positively correlated with response time variability for the flanker task. Methylphenidate initiated a partial anti-phase TPN/DMN synchronization, reduced variability, and abolished the variability/DMN correlation. CONCLUSION: Although results should be interpreted cautiously because the sample size is small, they suggest that a failure of the TPN/DMN synchronization could be involved in the moment-to-moment variability in ADHD. Methylphenidate initiated TPN/DMN synchronization, which in turn appeared to reduce variability.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Metilfenidato/farmacologia , Rede Nervosa/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Metilfenidato/administração & dosagem
15.
Planta ; 244(6): 1315-1328, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27541496

RESUMO

MAIN CONCLUSION: AtNPF3.1 gene expression is promoted by limiting nitrogen nutrition. Atnpf3.1 mutants are affected in hypocotyl elongation and seed germination under conditions of low-nitrate availability. The NITRATE TRANSPORTER1/PEPTIDE TRANSPORTER (NPF) family encodes nitrate or peptides transporters, some of which are also able to transport hormones. AtNPF3.1 has been described as a nitrate/nitrite/gibberellin transporter. Until now only its gibberellins (GAs) transport capacity have been proven in planta. We further analyzed its substrate specificity towards different GA species using a yeast heterologous system which revealed that (1) NPF3.1 transported not only bioactive GAs but also their precursors and metabolites and (2) the GAs' import activity of NPF3.1 was not affected by the presence of exogenous nitrate. Gene expression analysis along with germination assays and hypocotyl length measurements of loss of function mutants was used to understand the in planta role of NPF3.1. GUS staining revealed that this gene is expressed mainly in the endodermis of roots and hypocotyls, in shoots, stamens, and dry seeds. Germination assays in the presence of paclobutrazol, a GA biosynthesis inhibitor, revealed that the germination rate of npf3.1 mutants was lower compared to wild type when GA was added at the same time. Likewise, hypocotyl length measurements showed that the npf3.1 mutants were less sensitive to exogenous GA addition in the presence of paclobutrazol, compared to wild type. Moreover, this phenotype was observed only when plants were grown on low-nitrate supply. In addition, NPF3.1 gene expression was upregulated by low exogenous nitrate concentrations and the npf3.1 mutants exhibited a not yet described GA-related phenotype under these conditions. All together, these results indicated that NPF3.1 is indeed involved in GAs transport in planta under low-nitrate conditions.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Nitrogênio/fisiologia , Proteínas de Transporte de Ânions/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Giberelinas/metabolismo , Microscopia Confocal , Transportadores de Nitrato , Nitratos/metabolismo , Nitratos/fisiologia , Nitrogênio/metabolismo , Fenótipo , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia
16.
Epilepsia ; 57(7): 1069-77, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27237724

RESUMO

OBJECTIVE: Attention-deficit/hyperactivity disorder (ADHD) is commonly observed in children with epilepsy. However, factors associated with the development of ADHD and which might help to guide its therapeutic management, remain an issue of debate. METHODS: We conducted a multicenter prospective observational study that included children, aged 6-16 years, with both epilepsy and ADHD according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. After inclusion, patients entered a 12-16 week follow-up period during which they were either treated with methylphenidate or they did not receive specific ADHD treatment. ADHD was evaluated with the ADHD Rating Scale-IV. RESULTS: One hundred sixty-seven patients were included, of which 91 were seizure-free during the preinclusion baseline period. At inclusion, the ADHD Rating Scale-IV total score was 30.4 ± (standard deviation) 9.2, the inattentive subscore was 17.3 ± 4.4, and the hyperactive subscore was 13.2 ± 6.6. We did not detect any difference of ADHD Rating Scale-IV scores across patients' age or gender, age at epilepsy onset, epilepsy syndrome, seizure frequency, or number of ongoing antiepileptic drugs. Methylphenidate was initiated in 61 patients, including 55 in whom a follow-up evaluation was available. At the last follow-up, 41 patients (75%) treated with methylphenidate and 39 (42%) of those who did not received ADHD therapy demonstrated ≥25% decrease of ADHD Rating Scale-IV total score (p < 0.001). Response to methylphenidate was greater in girls but was not influenced by any epilepsy-related variables. SIGNIFICANCE: We did not detect any epilepsy-related factor associated with the severity of ADHD. Twenty-five percent of patients did not respond to methylphenidate. A better understanding of the pathologic process that underlies ADHD development in childhood epilepsy might be required to improve therapeutic strategies.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Epilepsia/complicações , Metilfenidato/uso terapêutico , Adolescente , Estimulantes do Sistema Nervoso Central/efeitos adversos , Criança , Feminino , Seguimentos , Humanos , Masculino , Metilfenidato/efeitos adversos , Estudos Prospectivos , Índice de Gravidade de Doença
17.
Am J Hum Genet ; 98(5): 971-980, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27108797

RESUMO

Gillespie syndrome (GS) is a rare variant form of aniridia characterized by non-progressive cerebellar ataxia, intellectual disability, and iris hypoplasia. Unlike the more common dominant and sporadic forms of aniridia, there has been no significant association with PAX6 mutations in individuals with GS and the mode of inheritance of the disease had long been regarded as uncertain. Using a combination of trio-based whole-exome sequencing and Sanger sequencing in five simplex GS-affected families, we found homozygous or compound heterozygous truncating mutations (c.4672C>T [p.Gln1558(∗)], c.2182C>T [p.Arg728(∗)], c.6366+3A>T [p.Gly2102Valfs5(∗)], and c.6664+5G>T [p.Ala2221Valfs23(∗)]) and de novo heterozygous mutations (c.7687_7689del [p.Lys2563del] and c.7659T>G [p.Phe2553Leu]) in the inositol 1,4,5-trisphosphate receptor type 1 gene (ITPR1). ITPR1 encodes one of the three members of the IP3-receptors family that form Ca(2+) release channels localized predominantly in membranes of endoplasmic reticulum Ca(2+) stores. The truncation mutants, which encompass the IP3-binding domain and varying lengths of the modulatory domain, did not form functional channels when produced in a heterologous cell system. Furthermore, ITPR1 p.Lys2563del mutant did not form IP3-induced Ca(2+) channels but exerted a negative effect when co-produced with wild-type ITPR1 channel activity. In total, these results demonstrate biallelic and monoallelic ITPR1 mutations as the underlying genetic defects for Gillespie syndrome, further extending the spectrum of ITPR1-related diseases.


Assuntos
Aniridia/etiologia , Ataxia Cerebelar/etiologia , Genes Dominantes/genética , Genes Recessivos/genética , Receptores de Inositol 1,4,5-Trifosfato/genética , Deficiência Intelectual/etiologia , Mutação/genética , Adolescente , Aniridia/patologia , Ataxia Cerebelar/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/patologia , Masculino , Linhagem
18.
Eur J Paediatr Neurol ; 20(3): 346-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26922364

RESUMO

BACKGROUND/PURPOSE: Vagus nerve stimulation (VNS) has been demonstrated to be safe and effective for adults and children with drug-resistant epilepsy and is able to improve most types of epilepsy. The aim of this study, in a paediatric population, was to assess the overall efficacy of vagus nerve stimulation on seizures, to assess tolerability and quality of life. METHODS: This single-centre, retrospective study reviewed the files of 29 children in whom a vagus nerve stimulator was implanted between 1995 and 2012. The response rate (greater than 50% reduction of the seizure frequency), antiepileptic efficacy according to the type of epilepsy or age at implantation or age at onset of epilepsy, the time-course of seizures, adverse effects, overall quality of life and number of hospitalisations were studied. RESULTS: In our population, vagus nerve stimulation achieved a significant reduction in the seizure frequency throughout follow-up (p = 0.015). Response rates were 59% at 3 months, and 66% at 6 months, and the response rate then remained stable at about 70%. Stimulation tended to be more effective in patients with non-idiopathic partial epilepsy than in patients with non-idiopathic and idiopathic generalised epilepsy (0.01 < p < 0.11). No other predictive factors of efficacy were identified. Patients, parents, caregivers reported improvement in overall quality of life in 38% of patients during clinical interviews. A significant reduction in the number of hospitalisations due to a reduction of seizure frequency was observed after implantation (p = 0.03). VNS was stopped because of complications or insufficient efficacy in 9 cases. CONCLUSION: Vagus nerve stimulation is a safe and effective treatment option in children with drug-resistant epilepsy who are not candidates for surgery.


Assuntos
Epilepsia Resistente a Medicamentos/terapia , Avaliação de Resultados em Cuidados de Saúde , Estimulação do Nervo Vago/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos
19.
Ann Neurol ; 78(6): 871-86, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26288984

RESUMO

OBJECTIVE: Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is caused by mutations in the SACS gene. SACS encodes sacsin, a protein whose function remains unknown, despite the description of numerous protein domains and the recent focus on its potential role in the regulation of mitochondrial physiology. This study aimed to identify new mutations in a large population of ataxic patients and to functionally analyze their cellular effects in the mitochondrial compartment. METHODS: A total of 321 index patients with spastic ataxia selected from the SPATAX network were analyzed by direct sequencing of the SACS gene, and 156 patients from the ATAXIC project presenting with congenital ataxia were investigated either by targeted or whole exome sequencing. For functional analyses, primary cultures of fibroblasts were obtained from 11 patients carrying either mono- or biallelic variants, including 1 case harboring a large deletion encompassing the entire SACS gene. RESULTS: We identified biallelic SACS variants in 33 patients from SPATAX, and in 5 nonprogressive ataxia patients from ATAXIC. Moreover, a drastic and recurrent alteration of the mitochondrial network was observed in 10 of the 11 patients tested. INTERPRETATION: Our results permit extension of the clinical and mutational spectrum of ARSACS patients. Moreover, we suggest that the observed mitochondrial network anomalies could be used as a trait biomarker for the diagnosis of ARSACS when SACS molecular results are difficult to interpret (ie, missense variants and heterozygous truncating variant). Based on our findings, we propose new diagnostic definitions for ARSACS using clinical, genetic, and cellular criteria.


Assuntos
Biomarcadores , Proteínas de Choque Térmico/fisiologia , Mitocôndrias , Espasticidade Muscular/diagnóstico , Ataxias Espinocerebelares/congênito , Adolescente , Adulto , Técnicas de Cultura de Células , Criança , Estudos de Coortes , Feminino , Fibroblastos , Proteínas de Choque Térmico/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Espasticidade Muscular/genética , Espasticidade Muscular/patologia , Espasticidade Muscular/fisiopatologia , Mutação , Ataxias Espinocerebelares/diagnóstico , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Ataxias Espinocerebelares/fisiopatologia , Adulto Jovem
20.
Psychiatry Res ; 233(1): 50-6, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26025013

RESUMO

The results of several previous magnetic resonance imaging studies suggest that the fronto-striato-thalamic circuitry is involved in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD). However, few studies have investigated the putative association between quantitative diffusion tensor imaging measurements of subcortical gray matter and subject task performances in children with ADHD. Here, we examined whether reaction time (RT) parameters during a flanker task were correlated with mean diffusivity (MD) measurements in the basal ganglia and thalamus in children with ADHD and in controls. For the study group as a whole, both the mean RT and the intra-individual variability in RTs were found to be significantly correlated with MD measurements in the right and left caudate, putamen and thalamus. In contrast, the correlation between the interference effect and MD failed to reach statistical significance. The present results may advance our understanding of the anatomical substrates of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Substância Cinzenta/fisiopatologia , Individualidade , Tempo de Reação/fisiologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Mapeamento Encefálico , Criança , Imagem de Tensor de Difusão/métodos , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
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