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The present study was designed to test the hypothesis that blood fearful and nonfearful individuals would be differentiated by their pattern of recall of schematic and non-schematic prose material. Blood fearful (n=36) and nonfearful (n=40) individuals were presented with five prose passages describing harm or injury. Nine sentences in each passage described events representative of the schema content of most individuals, whereas six sentences in each passage described events that are not representative of typical schema content. Participants read passages that either described themselves experiencing the situations or described themselves witnessing others in the situations and completed a free recall task in both immediate (i.e. 2 minutes) and delayed (i.e. one week) recall conditions. Results did not replicate studies from the cognitive psychology literature on which this study was based. Instead, participants who read passages describing themselves in these situations recalled the gist of the material more accurately than participants who read passages in which they witnessed another individual in the situation. Blood fearful participants recalled the affective tone of neutral passages less accurately than nonfearful participants. Results suggest that activation of schema content has little influence on memory performance, although assessing the affective tone of recalled material detected subtle differences in memory performance between fearful and nonfearful groups.

Malformations of cortical development containing dysplastic neuronal and glial elements, including hemimegalencephaly and focal cortical dysplasia, are common causes of intractable paediatric epilepsy. In this study we performed multiplex targeted sequencing of 10 genes in the PI3K/AKT pathway on brain tissue from 33 children who underwent surgical resection of dysplastic cortex for the treatment of intractable epilepsy. Sequencing results were correlated with clinical, imaging, pathological and immunohistological phenotypes. We identified mosaic activating mutations in PIK3CA and AKT3 in this cohort, including cancer-associated hotspot PIK3CA mutations in dysplastic megalencephaly, hemimegalencephaly, and focal cortical dysplasia type IIa. In addition, a germline PTEN mutation was identified in a male with hemimegalencephaly but no peripheral manifestations of the PTEN hamartoma tumour syndrome. A spectrum of clinical, imaging and pathological abnormalities was found in this cohort. While patients with more severe brain imaging abnormalities and systemic manifestations were more likely to have detected mutations, routine histopathological studies did not predict mutation status. In addition, elevated levels of phosphorylated S6 ribosomal protein were identified in both neurons and astrocytes of all hemimegalencephaly and focal cortical dysplasia type II specimens, regardless of the presence or absence of detected PI3K/AKT pathway mutations. In contrast, expression patterns of the T308 and S473 phosphorylated forms of AKT and in vitro AKT kinase activities discriminated between mutation-positive dysplasia cortex, mutation-negative dysplasia cortex, and non-dysplasia epilepsy cortex. Our findings identify PI3K/AKT pathway mutations as an important cause of epileptogenic brain malformations and establish megalencephaly, hemimegalencephaly, and focal cortical dysplasia as part of a single pathogenic spectrum.

The microcephaly-lymphedema-chorioretinal dysplasia (MLCRD) syndrome is a distinct microcephaly syndrome. The hallmark features, microcephaly, chorioretinopathy, and lymphedema are frequently recognized at birth. Another clinical entity, the chorioretinal dysplasia, microcephaly and mental retardation syndrome (CDMMR) is a highly overlapping syndrome characterized by more variable lymphedema. Recently, heterozygous mutations in KIF11, a gene encoding a critical spindle motor protein of the Kinesin family, have been reported in individuals with MLCRD, and in individuals with CDMMR. This finding is suggestive of a single clinically variable spectrum. Here, we report on de novo novel mutations of KIF11 in five individuals with severe microcephaly, marked simplification of the gyral pattern on neuroimaging, bilateral chorioretinopathy, and developmental delay. Three patients had congenital lymphedema, and one had congenital bilateral sensorineural hearing loss. This report, therefore, further expands the clinical and molecular spectrum of KIF11-associated microcephaly.