Adaptive functioning and neurodevelopment in patients with Dravet syndrome: 12-month interim analysis of the BUTTERFLY observational study.

OBJECTIVE: The BUTTERFLY observational study aims to elucidate the natural trajectory of Dravet syndrome (DS) and associated comorbidities in order to establish a baseline for clinical therapies. We present the 12-month interim analysis of the study. MATERIALS AND METHODS: Patients with a genetically confirmed diagnosis of DS were enrolled in the study. Adaptive functioning and neurodevelopmental status were measured using the Vineland Adaptive Behavior Scale, Third Edition (Vineland-III), Bayley Scales of Infant Development, Third Edition (BSID-III), and Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV). Executive function, ambulatory function and locomotor activities, and overall clinical status were measured using the Behavior Rating Inventory of Executive Function - Preschool Version (BRIEF-P) scale, Gillette Functional Assessment Questionnaire (Gillette FAQ), and Clinician or Caregiver Global Impression of Change scales (CGI-C or CaGI-C) respectively. RESULTS: Overall, 36 patients were enrolled across three age groups, with 35 patients completing at least part or all of one post-baseline visit through Month 12. Significant improvements in receptive communication, as assessed by Vineland-III and BSID-III raw scores, and in verbal comprehension subtests, as assessed by WPPSI-IV raw scores, were observed in BUTTERFLY patients for the all-patient group. Many patients performed on the impaired end of the BRIEF-P Global Executive Composite scale at baseline suggesting difficulties in executive function, and no significant change was observed in BRIEF-P scores for the all-patient group. Most patients performed in the dynamic range of the Gillette FAQ at baseline, and no significant change was observed in Gillette FAQ scores for the all-patient group. Lastly, there was significant improvement observed in the CaGI-C scores for the all-patient group. SIGNIFICANCE: This BUTTERFLY interim analysis shows small improvements in communication skills along with stability in other developmental abilities across patients with DS enrolled in the study from baseline to Month 12.

Loss of the neural-specific BAF subunit ACTL6B relieves repression of early response genes and causes recessive autism.

Synaptic activity in neurons leads to the rapid activation of genes involved in mammalian behavior. ATP-dependent chromatin remodelers such as the BAF complex contribute to these responses and are generally thought to activate transcription. However, the mechanisms keeping such "early activation" genes silent have been a mystery. In the course of investigating Mendelian recessive autism, we identified six families with segregating loss-of-function mutations in the neuronal BAF (nBAF) subunit ACTL6B (originally named BAF53b). Accordingly, ACTL6B was the most significantly mutated gene in the Simons Recessive Autism Cohort. At least 14 subunits of the nBAF complex are mutated in autism, collectively making it a major contributor to autism spectrum disorder (ASD). Patient mutations destabilized ACTL6B protein in neurons and rerouted dendrites to the wrong glomerulus in the fly olfactory system. Humans and mice lacking ACTL6B showed corpus callosum hypoplasia, indicating a conserved role for ACTL6B in facilitating neural connectivity. Actl6b knockout mice on two genetic backgrounds exhibited ASD-related behaviors, including social and memory impairments, repetitive behaviors, and hyperactivity. Surprisingly, mutation of Actl6b relieved repression of early response genes including AP1 transcription factors (Fos, Fosl2, Fosb, and Junb), increased chromatin accessibility at AP1 binding sites, and transcriptional changes in late response genes associated with early response transcription factor activity. ACTL6B loss is thus an important cause of recessive ASD, with impaired neuron-specific chromatin repression indicated as a potential mechanism.

Bi-allelic Loss of Human APC2, Encoding Adenomatous Polyposis Coli Protein 2, Leads to Lissencephaly, Subcortical Heterotopia, and Global Developmental Delay.

Lissencephaly is a severe brain malformation in which failure of neuronal migration results in agyria or pachygyria and in which the brain surface appears unusually smooth. It is often associated with microcephaly, profound intellectual disability, epilepsy, and impaired motor abilities. Twenty-two genes are associated with lissencephaly, accounting for approximately 80% of disease. Here we report on 12 individuals with a unique form of lissencephaly; these individuals come from eight unrelated families and have bi-allelic mutations in APC2, encoding adenomatous polyposis coli protein 2. Brain imaging studies demonstrate extensive posterior predominant lissencephaly, similar to PAFAH1B1-associated lissencephaly, as well as co-occurrence of subcortical heterotopia posterior to the caudate nuclei, "ribbon-like" heterotopia in the posterior frontal region, and dysplastic in-folding of the mesial occipital cortex. The established role of APC2 in integrating the actin and microtubule cytoskeletons to mediate cellular morphological changes suggests shared function with other lissencephaly-encoded cytoskeletal proteins such as α-N-catenin (CTNNA2) and platelet-activating factor acetylhydrolase 1b regulatory subunit 1 (PAFAH1B1, also known as LIS1). Our findings identify APC2 as a radiographically distinguishable recessive form of lissencephaly.

Restricted diffusion of the callosal splenium is highly specific for seizures in neonates.

BACKGROUND: To determine whether restricted diffusion of the callosal splenium is specific for seizure activity in neonates. METHODS: We performed a retrospective chart review of 123 neonates who had a diagnosis of hypoxic ischemic encephalopathy (HIE) who underwent therapeutic cooling and had magnetic resonance imaging (MRI) within the first 10 days of life. The regions examined for injury include the callosal splenium, cortex, deep gray matter, and subcortical white matter. Neurodevelopmental outcomes were secondarily assessed using the Bayley Scales of Infant Development at 12 to 18 months of age and > 18 months of age. APGAR scores and pH, two important markers of hypoxia/ischemia and encephalopathy, were also analyzed in relation to these outcomes. RESULTS: Approximately 41% of the neonates had at least one abnormal region on brain MRI, and 21% had abnormal signal in the splenium. Clinical and/or electrographic seizures were documented in 32%. Changes in the splenium had a sensitivity of 54%, specificity of 94%, and positive predictive value of 81% for seizure presence. The presence of seizures and splenium lesion was associated poor developmental outcomes at 12 to 18 months of age. APGAR scores at 10 minutes, but not lowest pH was associated with splenial changes. CONCLUSIONS: Restricted diffusion of the callosal splenium is specific for recent seizures in neonates with HIE. Seizures and splenial lesion represent risk factors for poor neurodevelopmental outcomes. Child neurologists and neonatologists should consider splenial signal abnormality in their assessment of neonates at risk for seizures and counsel families about likely outcomes accordingly.

Interim results of adaptive functioning and neurodevelopment in BUTTERFLY - An observational study of children and adolescents with Dravet syndrome.

PURPOSE: The purpose of this study is to evaluate adaptive functioning and neurodevelopment study assessments in a prospective study of patients with Dravet syndrome (DS). We present 3-month interim adaptive functioning and neurodevelopment data from the prospective, observational BUTTERFLY study in patients with DS aged 2-18 years. RESULTS: BUTTERFLY enrolled thirty-six patients divided 1:1:1 across three age groups (2-7: 8-12: and 13-18 years). Most enrolled patients were female (61.1%), white (94.4%), and non-Latino (83.3%) with a mean (standard deviation; SD) age of 10.8 (5.2) years and a mean (range) age of seizure onset of 0.4 (0.2-1.0) years. Patients used a mean (SD) of 3.5 (1.63) anti-seizure therapies at baseline. Regression analysis of the baseline Vineland Adaptive Behavior Scale - third edition (VABS-III) composite score indicated that the gap in adaptive function between patients with DS (n = 33) and neurotypical children widens with age. Similarly, developmental quotients calculated for patients who completed all Bayley Scales of Infant Development - third edition (BSID-III) subtests at baseline (n = 15) highlighted a gap in intellectual functioning between patients with DS and neurotypical children that widens with age. More patients in the two older age groups were able to validly complete the Wechsler Preschool and Primary Scale of Intelligence - fourth edition (WPPSI-IV) at baseline compared with the youngest age group. There were trends towards higher raw scores, albeit of low magnitude, in the oldest age group compared with the younger age two groups across multiple VABS-III domains and WPPSI-IV subtests. All three measures showed no significant change in the all-patients analyses and demonstrated relatively low intra-patient variability from baseline to Month 3. CONCLUSIONS: Three-month interim data from BUTTERFLY demonstrated the feasibility of utilizing the VABS-III, BSID-III, and WPPSI-IV for the assessment of adaptive function and neurodevelopment in future clinical studies of DS. Moreover, many patients with DS appear to gain neurodevelopmental and adaptive function skills over time, although at a slower rate and lower magnitude than that seen in the neurotypical population.

Human-specific microglial Siglec-11 transcript variant has the potential to affect polysialic acid-mediated brain functions at a distance.

CD33-related Siglecs are often found on innate immune cells and modulate their reactivity by recognition of sialic acid-based "self-associated molecular patterns" and signaling via intracellular tyrosine-based cytosolic motifs. Previous studies have shown that Siglec-11 specifically binds to the brain-enriched polysialic acid (polySia/PSA) and that its microglial expression in the brain is unique to humans. Furthermore, human microglial Siglec-11 exists as an alternate splice form missing the exon encoding the last (fifth) Ig-like C2-set domain of the extracellular portion of the protein, but little is known about the functional consequences of this variation. Here, we report that the recombinant soluble human microglial form of Siglec-11 (hSiglec-11(4D)-Fc) binds endogenous and immobilized polySia better than the tissue macrophage form (hSiglec-11(5D)-Fc) or the chimpanzee form (cSiglec-11(5D)-Fc). The Siglec-11 protein is also prone to aggregation, potentially influencing its ligand-binding ability. Additionally, Siglec-11 protein can be secreted in both intact and proteolytically cleaved forms. The microglial splice variant has reduced proteolytic release and enhanced incorporation into exosomes, a process that appears to be regulated by palmitoylation of cysteines in the cytosolic tail. Taken together, these data demonstrate that human brain specific microglial hSiglec-11(4D) has different molecular properties and can be released on exosomes and/or as proteolytic products, with the potential to affect polySia-mediated brain functions at a distance.

Lysosomal cholesterol accumulation contributes to the movement phenotypes associated with NUS1 haploinsufficiency.

PURPOSE: Variants in NUS1 are associated with a congenital disorder of glycosylation, developmental and epileptic encephalopathies, and are possible contributors to Parkinson disease pathogenesis. How the diverse functions of the NUS1-encoded Nogo B receptor (NgBR) relate to these different phenotypes is largely unknown. We present three patients with de novo heterozygous variants in NUS1 that cause a complex movement disorder, define pathogenic mechanisms in cells and zebrafish, and identify possible therapy. METHODS: Comprehensive functional studies were performed using patient fibroblasts, and a zebrafish model mimicking NUS1 haploinsufficiency. RESULTS: We show that de novo NUS1 variants reduce NgBR and Niemann-Pick type C2 (NPC2) protein amount, impair dolichol biosynthesis, and cause lysosomal cholesterol accumulation. Reducing nus1 expression 50% in zebrafish embryos causes abnormal swim behaviors, cholesterol accumulation in the nervous system, and impaired turnover of lysosomal membrane proteins. Reduction of cholesterol buildup with 2-hydroxypropyl-ß-cyclodextrin significantly alleviates lysosomal proteolysis and motility defects. CONCLUSION: Our results demonstrate that these NUS1 variants cause multiple lysosomal phenotypes in cells. We show that the movement deficits associated with nus1 reduction in zebrafish arise in part from defective efflux of cholesterol from lysosomes, suggesting that treatments targeting cholesterol accumulation could be therapeutic.

Improved methods to characterize the length and quantity of highly unstable PolySialic acids subject category: (Carbohydrates, chromatographic techniques).

Polysialic acid (polySia) is a linear homopolymer of α2-8-linked sialic acids that is highly expressed during early stages of mammalian brain development and modulates a multitude of cellular functions. While degree of polymerization (DP) can affect such functions, currently available methods do not accurately characterize this parameter, because of the instability of the polymer. We developed two improved methods to characterize the DP and total polySia content in biological samples. PolySia chains with exposed reducing termini can be derivatized with DMB for subsequent HPLC analysis. However, application to biological samples of polySia-glycoproteins requires release of polySia chains from the underlying glycan, which is difficult to achieve without concurrent partial hydrolysis of the α2-8-linkages of the polySia chain, affecting its accurate characterization. We report an approach to protect internal α2-8sia linkages of long polySia chains, using previously known esterification conditions that generate stable polylactone structures. Such polylactonized molecules are more stable during acid hydrolysis release and acidic DMB derivatization. Additionally, we used the highly specific Endoneuraminidase-NF enzyme to discriminate polysialic acid and other sialic acid and developed an approach to precisely measure the total content of polySia in a biological sample. These two methods provide improved quantification and characterization of polySia.

Tumor-related epilepsy: epidemiology, pathogenesis and management.

INTRODUCTION: Seizure is a common comorbidity in patients with brain tumor. It may be the presenting symptom or develop after the tumor diagnosis. The underlying pathophysiology of brain tumor-related epilepsy remains poorly understood. METHODS: A comprehensive literature review of Pubmed English articles from 1980-2017 was performed to summarize current knowledge and treatment options of brain tumor-related epilepsy. RESULTS: Multiple factors have been found to contribute to tumor-related epilepsy, including tumor type, speed of tumor growth, location, and tumor burden. The underlying pathogenesis of epilepsy is not clear but perturbations in the peri-tumoral regions, both structural and cellular communications, have been implicated. CONCLUSIONS: Surgical and medical treatments of tumor-related epilepsy remain challenging as additional factors such as the extent of surgical resection, interactions with tumor-related oncological treatments and anti-epileptic medication related side effects need to be considered.

A critical role for IGF-II in memory consolidation and enhancement.

We report that, in the rat, administering insulin-like growth factor II (IGF-II, also known as IGF2) significantly enhances memory retention and prevents forgetting. Inhibitory avoidance learning leads to an increase in hippocampal expression of IGF-II, which requires the transcription factor CCAAT enhancer binding protein ß and is essential for memory consolidation. Furthermore, injections of recombinant IGF-II into the hippocampus after either training or memory retrieval significantly enhance memory retention and prevent forgetting. To be effective, IGF-II needs to be administered within a sensitive period of memory consolidation. IGF-II-dependent memory enhancement requires IGF-II receptors, new protein synthesis, the function of activity-regulated cytoskeletal-associated protein and glycogen-synthase kinase 3 (GSK3). Moreover, it correlates with a significant activation of synaptic GSK3ß and increased expression of GluR1 (also known as GRIA1) α-amino-3-hydroxy-5-methyl-4-isoxasolepropionic acid receptor subunits. In hippocampal slices, IGF-II promotes IGF-II receptor-dependent, persistent long-term potentiation after weak synaptic stimulation. Thus, IGF-II may represent a novel target for cognitive enhancement therapies.

A positive autoregulatory BDNF feedback loop via C/EBPß mediates hippocampal memory consolidation.

Little is known about the temporal progression and regulation of the mechanisms underlying memory consolidation. Brain-derived-neurotrophic-factor (BDNF) has been shown to mediate the maintenance of memory consolidation, but the mechanisms of this regulation remain unclear. Using inhibitory avoidance (IA) in rats, here we show that a hippocampal BDNF-positive autoregulatory feedback loop via CCAAT-enhancer binding protein ß (C/EBPß) is necessary to mediate memory consolidation. At training, a very rapid, learning-induced requirement of BDNF accompanied by rapid de novo translation controls the induction of a persistent activation of cAMP-response element binding-protein (CREB) and C/EBPß expression. The latter, in turn, controls an increase in expression of bdnf exon IV transcripts and BDNF protein, both of which are necessary and, together with the initial BDNF requirement, mediate memory consolidation. The autoregulatory loop terminates by 48 h after training with decreased C/EBPß and pCREB and increased methyl-CpG binding protein-2, histone-deacetylase-2, and switch-independent-3a binding at the bdnf exon IV promoter.

The effect of insulin and insulin-like growth factors on hippocampus- and amygdala-dependent long-term memory formation.

Recent work has reported that the insulin-like growth factor 2 (IGF2) promotes memory enhancement. Furthermore, impaired insulin or IGF1 functions have been suggested to play a role in the pathogenesis of neurodegeneration and cognitive impairments, hence implicating the insulin/IGF system as an important target for cognitive enhancement and/or the development of novel treatments against cognitive disorders. Here, we tested the effect of intracerebral injections of IGF1, IGF2, or insulin on memory consolidation and persistence in rats. We found that a bilateral injection of insulin into the dorsal hippocampus transiently enhances hippocampal-dependent memory and an injection of IGF1 has no effect. None of the three peptides injected into the amygdala affected memories critically engaging this region. Together with previous data on IGF2, these results indicate that IGF2 produces the most potent and persistent effect as a memory enhancer on hippocampal-dependent memories. We suggest that the memory-enhancing effects of insulin and IGF2 are likely mediated by distinct mechanisms.

Sonography of musculoskeletal soft-tissue masses: techniques, pearls, and pitfalls.

OBJECTIVE: The purpose of this article is to review the appropriate use of ultrasound in the workup of soft-tissue masses of the extremities. The normal sonographic appearance of superficial soft tissues, the importance of proper technique in image acquisition, and the characteristic sonographic appearance of certain masses and potential pitfalls are discussed. CONCLUSION: Ultrasound is increasingly being used for the initial evaluation of soft-tissue masses of the extremities. Certain clinical and imaging findings allow diagnosis of selected soft-tissue masses; however, most imaging findings are nonspecific, and further evaluation is necessary. The many potential pitfalls can lead to adverse patient outcomes.

Partially intraosseous schwannoma of the distal humerus with increased enhancement after biopsy: Radiologic-pathologic correlation.

Intraosseous schwannomas are rare benign tumors that most often occur at the mandible or sacrum. We present an unusual case of a bilobed schwannoma of the distal humerus with both intraosseous and extraosseous components. The extraosseous component was non-enhancing on initial MRI and enhanced on a subsequent MRI obtained after biopsy. We hypothesize that this change was attributable to decreased intra-tumoral pressure secondary to biopsy-related disruption of the tumor capsule.

A Case of Tuberculosis-Associated Acute Disseminated Encephalomyelitis in a Seven-Month-Old Infant.

A seven-month-old previously healthy female infant presented with acute onset encephalopathy and left focal weakness in the setting of three months of non-productive cough. She was diagnosed with pulmonary tuberculosis (TB), and neuroimaging showed multifocal non-enhancing T2 hyperintensities in the brain and longitudinal T2 hyperintensity in the spinal cord consistent with acute disseminated encephalomyelitis (ADEM). However, her cerebrospinal fluid (CSF) did not show evidence of TB infection. She was treated with high-dose steroids for five days with a steroid taper along with antitubercular medications with a remarkable recovery in gross motor function. This case suggests a previously unreported association between TB and an immune-mediated demyelinating syndrome in children that is clinically distinct from other more common forms of TB-associated central nervous system (CNS) complications.

Polyostotic osteoid osteoma: A case report.

Osteoid osteomas are common, benign osteoblastic tumors that can occur in any bone in the body. They are almost always solitary, with only rare reports of multiple tumors in the same patient. When multiple, they typically are found within the same bone. We present a unique case of a young female athlete who presented initially at 16 years old with a right tibial osteoid osteoma and later at 18 years old with a right acetabular osteoid osteoma. Our case demonstrates the rare entity of polyostotic osteoid osteoma, the potential limitations of MRI in the diagnosis of osteoid osteoma, and the utility of radiofrequency ablation in the treatment of osteoid osteoma.

Loss of NARS1 impairs progenitor proliferation in cortical brain organoids and leads to microcephaly.

Asparaginyl-tRNA synthetase1 (NARS1) is a member of the ubiquitously expressed cytoplasmic Class IIa family of tRNA synthetases required for protein translation. Here, we identify biallelic missense and frameshift mutations in NARS1 in seven patients from three unrelated families with microcephaly and neurodevelopmental delay. Patient cells show reduced NARS1 protein, impaired NARS1 activity and impaired global protein synthesis. Cortical brain organoid modeling shows reduced proliferation of radial glial cells (RGCs), leading to smaller organoids characteristic of microcephaly. Single-cell analysis reveals altered constituents of both astrocytic and RGC lineages, suggesting a requirement for NARS1 in RGC proliferation. Our findings demonstrate that NARS1 is required to meet protein synthetic needs and to support RGC proliferation in human brain development.

Consensus survey on pre-procedural safety practices in radiological examinations: a multicenter study in seven Asian regions.

OBJECTIVE: To understand the status of pre-procedural safety practices in radiological examinations at radiology residency training institutions in various Asian regions. METHODS: A questionnaire based on the Joint Commission International Accreditation Standards was electronically sent to 3 institutions each in 10 geographical regions across 9 Asian countries. Questions addressing 45 practices were divided into 3 categories. A five-tier scale with numerical scores was used to evaluate safety practices in each institution. Responses obtained from three institutions in the United States were used to validate the execution rate of each surveyed safety practice. RESULTS: The institutional response rate was 70.0% (7 Asian regions, 21 institutions). 44 practices (all those surveyed except for the application of wrist tags for identifying patients with fall risks) were validated using the US participants. Overall, the Asian participants reached a consensus on 89% of the safety practices. Comparatively, most Asian participants did not routinely perform three pre-procedural practices in the examination appropriateness topic. CONCLUSION: Based on the responses from 21 participating Asian institutions, most routinely perform standard practices during radiological examinations except when it comes to examination appropriateness. This study can provide direction for safety policymakers scrutinizing and improving regional standards of care. ADVANCES IN KNOWLEDGE: This is the first multicenter survey study to elucidate pre-procedural safety practices in radiological examinations in seven Asian regions.