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This study used information processing paradigms to provide a detailed examination of executive function abilities in autism. The performance of non-retarded autistic children was compared with that of two matched control groups, one with Tourette Syndrome and the other developmentally normal. Autistic subjects performed as well as controls on tasks requiring global-local processing and inhibition of neutral responses. In contrast to both control groups, however, the autistic sample was significantly impaired on a measure of cognitive flexibility. The performance of children with Tourette Syndrome did not differ from that of normal controls on any task. These results refine our knowledge about executive dysfunction in autism and suggest a new conceptual framework and general method for investigating the cognitive underpinnings of neurodevelopmental disorders.

Vici syndrome is a recessively inherited multisystem disorder characterized by callosal agenesis, cataracts, cardiomyopathy, combined immunodeficiency and hypopigmentation. To investigate the molecular basis of Vici syndrome, we carried out exome and Sanger sequence analysis in a cohort of 18 patients. We identified recessive mutations in EPG5 (previously KIAA1632), indicating a causative role in Vici syndrome. EPG5 is the human homologue of the metazoan-specific autophagy gene epg-5, encoding a key autophagy regulator (ectopic P-granules autophagy protein 5) implicated in the formation of autolysosomes. Further studies demonstrated a severe block of autophagosomal clearance in muscle and fibroblasts from EPG5 mutant patients, resulting in autophagic cargo accumulation in autophagosomes. These findings indicate Vici syndrome as a paradigm of a human multisystem disorder associated with defective autophagy, and suggest a fundamental role of the autophagy pathway in the anatomical and functional formation of organs such as the brain, the heart and the immune system.

A follow-up study of a large Utah family with significant linkage to chromosome 2q24 led us to identify a new febrile seizure (FS) gene, SCN9A encoding Nav1.7. In 21 affected members, we uncovered a potential mutation in a highly conserved amino acid, p.N641Y, in the large cytoplasmic loop between transmembrane domains I and II that was absent from 586 ethnically matched population control chromosomes. To establish a functional role for this mutation in seizure susceptibility, we introduced the orthologous mutation into the murine Scn9a ortholog using targeted homologous recombination. Compared to wild-type mice, homozygous Scn9a N641Y/N641Y knockin mice exhibit significantly reduced thresholds to electrically induced clonic and tonic-clonic seizures, and increased corneal kindling acquisition rates. Together, these data strongly support the SCN9A p.N641Y mutation as disease-causing in this family. To confirm the role of SCN9A in FS, we analyzed a collection of 92 unrelated FS patients and identified additional highly conserved Nav1.7 missense variants in 5% of the patients. After one of these children with FS later developed Dravet syndrome (severe myoclonic epilepsy of infancy), we sequenced the SCN1A gene, a gene known to be associated with Dravet syndrome, and identified a heterozygous frameshift mutation. Subsequent analysis of 109 Dravet syndrome patients yielded nine Nav1.7 missense variants (8% of the patients), all in highly conserved amino acids. Six of these Dravet syndrome patients with SCN9A missense variants also harbored either missense or splice site SCN1A mutations and three had no SCN1A mutations. This study provides evidence for a role of SCN9A in human epilepsies, both as a cause of FS and as a partner with SCN1A mutations.

Inherited leukodystrophies are associated with substantial morbidity and mortality in children. Overall population incidence is higher than generally appreciated (1 in 7,663 live births). Most leukodystrophies remain undiagnosed, but a logical algorithm based on prevalence could aid testing.

Vici syndrome is a progressive neurodevelopmental multisystem disorder caused by mutations in the autophagy gene EPG5. Byrne et al. characterise the phenotype of 50 affected children, revealing callosal agenesis, cataracts, hypopigmentation, cardiomyopathy, immune dysfunction, developmental delay and microcephaly. Downregulation of epg5 in Drosophila results in autophagic abnormalities and progressive neurodegeneration.

Objective: To compare intranasal midazolam, using a Mucosal Atomization Device (IN-MMAD), with rectal diazepam (RD) for the home treatment of seizures in children with epilepsy.Design: Prospective randomized study.Setting: Patients' homes and a freestanding children's hospital that serves as a referral center for 5 states.Patients: A total of 358 pediatric patients who visited a pediatric neurology clinic from July 2006 through September 2008 and were prescribed a home rescue medication for their next seizure.Intervention: Caretakers were randomized to use either 0.2 mg/kg of IN-MMAD (maximum, 10 mg) or 0.3 to 0.5 mg/kg of RD (maximum, 20 mg) at home for their child's next seizure if it lasted more than 5 minutes.Outcome Measures: The primary outcome measure was total seizure time after medication administration. Our secondary outcome measures were total seizure time, time to medication administration, respiratory complications, emergency medical service support, emergency department visits, hospitalizations, and caretakers' ease of administration and satisfaction with the medication.Results: A total of 92 caretakers gave the study medication during a child's seizure (50 IN-MMAD, 42 RD). The median time from medication administration to seizure cessation for IN-MMAD was 1.3 minutes less than for RD (95% confidence interval, 0.0-3.5 minutes; P=.09). The median time to medication administration was 5.0 minutes for each group. No differences in complications were found between treatment groups. Caretakers were more satisfied with IN-MMAD and report that it was easier to give than RD. Conclusions:There was no detectable difference in efficacy between IN-MMAD and RD as a rescue medication for terminating seizures at home in pediatric patients with epilepsy. Ease of administration and overall satisfaction was higher with IN-MMAD compared with RD.