23 research outputs found

    Validation of the Arabic version of the Social Communication Questionnaire

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    Validated screening and diagnostic tools for autism spectrum disorder for use in Arabic-speaking individuals are scarce. This study validated the Arabic version of the Social Communication Questionnaire. The total study sample included 206 children with autism spectrum disorder and 206 typically developing children (73.8% male; mean age: 8.5 (standard deviation = 2.6) years). The mean Social Communication Questionnaire total score was significantly higher in autism spectrum disorder children than in typically developing children (p < 0.0001). Scores on the three Social Communication Questionnaire subscales also differed significantly between the groups (p < 0.001). Of the 39 items, 37 were endorsed significantly more often in the autism spectrum disorder group. The total Social Communication Questionnaire score did not vary by age or gender. Internal consistency was excellent (alpha = 0.92). In the receiver operating characteristic analysis, the area under the curve for the total score showed excellent discrimination between autism spectrum disorder and typically developing children (area under the curve = 0.95; 95% confidence interval: 0.93–0.97). The areas under the curve for the scale subscores were 0.923 (95% confidence interval: 0.898–0.949) for the social interaction score, 0.872 (95% confidence interval: 0.838–0.905) for the communication score, and 0.856 (95% confidence interval: 0.819–0.893) for the repetitive behaviors score. The findings support the use of the Arabic Social Communication Questionnaire to successfully differentiate children with clinically diagnosed autism spectrum disorder using the established cutoff value for the English version.The authors would like to thank all the staff of the autism centers and schools who contributed in distributing and collecting the SCQ forms. They also would like to thank Western Psychological Services (WPS) staff for their help during the process of translating and reviewing the Arabic SCQ. They acknowledge Jennifer Holmes, ELS, for medical editing. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The study was funded by the Qatar National Research Fund (NPRP 6-093-3-024)

    Optimal deployment of components of cloud-hosted application for guaranteeing multitenancy isolation

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    One of the challenges of deploying multitenant cloud-hosted services that are designed to use (or be integrated with) several components is how to implement the required degree of isolation between the components when there is a change in the workload. Achieving the highest degree of isolation implies deploying a component exclusively for one tenant; which leads to high resource consumption and running cost per component. A low degree of isolation allows sharing of resources which could possibly reduce cost, but with known limitations of performance and security interference. This paper presents a model-based algorithm together with four variants of a metaheuristic that can be used with it, to provide near-optimal solutions for deploying components of a cloud-hosted application in a way that guarantees multitenancy isolation. When the workload changes, the model based algorithm solves an open multiclass QN model to determine the average number of requests that can access the components and then uses a metaheuristic to provide near-optimal solutions for deploying the components. Performance evaluation showed that the obtained solutions had low variability and percent deviation when compared to the reference/optimal solution. We also provide recommendations and best practice guidelines for deploying components in a way that guarantees the required degree of isolation

    Clinico-radiological features, molecular spectrum, and identification of prognostic factors in developmental and epileptic encephalopathy due to inosine triphosphate pyrophosphatase (ITPase) deficiency

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    Developmental and epileptic encephalopathy 35 (DEE 35) is a severe neurological condition caused by biallelic variants in ITPA, encoding inosine triphosphate pyrophosphatase, an essential enzyme in purine metabolism. We delineate the genotypic and phenotypic spectrum of DEE 35, analyzing possible predictors for adverse clinical outcomes. We investigated a cohort of 28 new patients and reviewed previously described cases, providing a comprehensive characterization of 40 subjects. Exome sequencing was performed to identify underlying ITPA pathogenic variants. Brain MRI (magnetic resonance imaging) scans were systematically analyzed to delineate the neuroradiological spectrum. Survival curves according to the Kaplan–Meier method and log-rank test were used to investigate outcome predictors in different subgroups of patients. We identified 18 distinct ITPA pathogenic variants, including 14 novel variants, and two deletions. All subjects showed profound developmental delay, microcephaly, and refractory epilepsy followed by neurodevelopmental regression. Brain MRI revision revealed a recurrent pattern of delayed myelination and restricted diffusion of early myelinating structures. Congenital microcephaly and cardiac involvement were statistically significant novel clinical predictors of adverse outcomes. We refined the molecular, clinical, and neuroradiological characterization of ITPase deficiency, and identified new clinical predictors which may have a potentially important impact on diagnosis, counseling, and follow-up of affected individuals

    Loss-of-function mutations in UDP-Glucose 6-Dehydrogenase cause recessive developmental epileptic encephalopathy

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    Developmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patients’ primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy

    Loss-of-function mutations in UDP-Glucose 6-Dehydrogenase cause recessive developmental epileptic encephalopathy

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    AbstractDevelopmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patients’ primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy.</jats:p

    Expanding the genetic heterogeneity of intellectual disability

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    Intellectual disability (ID) is a common morbid condition with a wide range of etiologies. The list of monogenic forms of ID has increased rapidly in recent years thanks to the implementation of genomic sequencing techniques. In this study, we describe the phenotypic and genetic findings of 68 families (105 patients) all with novel ID-related variants. In addition to established ID genes, including ones for which we describe unusual mutational mechanism, some of these variants represent the first confirmatory disease-gene links following previous reports (TRAK1, GTF3C3, SPTBN4 and NKX6-2), some of which were based on single families. Furthermore, we describe novel variants in 14 genes that we propose as novel candidates (ANKHD1, ASTN2, ATP13A1, FMO4, MADD, MFSD11, NCKAP1, NFASC, PCDHGA10, PPP1R21, SLC12A2, SLK, STK32C and ZFAT). We highlight MADD and PCDHGA10 as particularly compelling candidates in which we identified biallelic likely deleterious variants in two independent ID families each. We also highlight NCKAP1 as another compelling candidate in a large family with autosomal dominant mild intellectual disability that fully segregates with a heterozygous truncating variant. The candidacy of NCKAP1 is further supported by its biological function, and our demonstration of relevant expression in human brain. Our study expands the locus and allelic heterogeneity of ID and demonstrates the power of positional mapping to reveal unusual mutational mechanisms

    Bi-allelic variants in HOPS complex subunit VPS41 cause cerebellar ataxia and abnormal membrane trafficking.

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    Membrane trafficking is a complex, essential process in eukaryotic cells responsible for protein transport and processing. Deficiencies in vacuolar protein sorting (VPS) proteins, key regulators of trafficking, cause abnormal intracellular segregation of macromolecules and organelles and are linked to human disease. VPS proteins function as part of complexes such as the homotypic fusion and vacuole protein sorting (HOPS) tethering complex, composed of VPS11, VPS16, VPS18, VPS33A, VPS39 and VPS41. The HOPS-specific subunit VPS41 has been reported to promote viability of dopaminergic neurons in Parkinson's disease but to date has not been linked to human disease. Here, we describe five unrelated families with nine affected individuals, all carrying homozygous variants in VPS41 that we show impact protein function. All affected individuals presented with a progressive neurodevelopmental disorder consisting of cognitive impairment, cerebellar atrophy/hypoplasia, motor dysfunction with ataxia and dystonia, and nystagmus. Zebrafish disease modelling supports the involvement of VPS41 dysfunction in the disorder, indicating lysosomal dysregulation throughout the brain and providing support for cerebellar and microglial abnormalities when vps41 was mutated. This provides the first example of human disease linked to the HOPS-specific subunit VPS41 and suggests the importance of HOPS complex activity for cerebellar function

    Clinical, neuroimaging, and molecular spectrum of TECPR2‐associated hereditary sensory and autonomic neuropathy with intellectual disability

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    Bi‐allelic TECPR2 variants have been associated with a complex syndrome with features of both a neurodevelopmental and neurodegenerative disorder. Here, we provide a comprehensive clinical description and variant interpretation framework for this genetic locus. Through international collaboration, we identified 17 individuals from 15 families with bi‐allelic TECPR2‐variants. We systemically reviewed clinical and molecular data from this cohort and 11 cases previously reported. Phenotypes were standardized using Human Phenotype Ontology terms. A cross‐sectional analysis revealed global developmental delay/intellectual disability, muscular hypotonia, ataxia, hyporeflexia, respiratory infections, and central/nocturnal hypopnea as core manifestations. A review of brain magnetic resonance imaging scans demonstrated a thin corpus callosum in 52%. We evaluated 17 distinct variants. Missense variants in TECPR2 are predominantly located in the N‐ and C‐terminal regions containing β‐propeller repeats. Despite constituting nearly half of disease‐associated TECPR2 variants, classifying missense variants as (likely) pathogenic according to ACMG criteria remains challenging. We estimate a pathogenic variant carrier frequency of 1/1221 in the general and 1/155 in the Jewish Ashkenazi populations. Based on clinical, neuroimaging, and genetic data, we provide recommendations for variant reporting, clinical assessment, and surveillance/treatment of individuals with TECPR2‐associated disorder. This sets the stage for future prospective natural history studies

    Clinico-radiological features, molecular spectrum, and identification of prognostic factors in developmental and epileptic encephalopathy due to inosine triphosphate pyrophosphatase (ITPase) deficiency.

    Get PDF
    Developmental and epileptic encephalopathy 35 (DEE 35) is a severe neurological condition caused by biallelic variants in ITPA, encoding inosine triphosphate pyrophosphatase, an essential enzyme in purine metabolism. We delineate the genotypic and phenotypic spectrum of DEE 35, analyzing possible predictors for adverse clinical outcomes. We investigated a cohort of 28 new patients and reviewed previously described cases, providing a comprehensive characterization of 40 subjects. Exome sequencing was performed to identify underlying ITPA pathogenic variants. Brain MRI (magnetic resonance imaging) scans were systematically analyzed to delineate the neuroradiological spectrum. Survival curves according to the Kaplan-Meier method and log-rank test were used to investigate outcome predictors in different subgroups of patients. We identified 18 distinct ITPA pathogenic variants, including 14 novel variants, and two deletions. All subjects showed profound developmental delay, microcephaly, and refractory epilepsy followed by neurodevelopmental regression. Brain MRI revision revealed a recurrent pattern of delayed myelination and restricted diffusion of early myelinating structures. Congenital microcephaly and cardiac involvement were statistically significant novel clinical predictors of adverse outcomes. We refined the molecular, clinical, and neuroradiological characterization of ITPase deficiency, and identified new clinical predictors which may have a potentially important impact on diagnosis, counseling, and follow-up of affected individuals

    Adapting evidence-based clinical practice guidelines for people with attention deficit hyperactivity disorder in Saudi Arabia: process and outputs of a national initiative

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    Abstract Background We recently adapted the published National Institute for Health and Care Excellence (NICE) Attention deficit hyperactivity disorder (ADHD) diagnosis and management guideline to the Saudi Arabian context. It has been postulated that adaptation of evidence-based clinical practice guidelines to the local healthcare context rather than de-novo development will improve their adoption and implementation without imposing a significant burden on resources. The objective of this paper is to describe the adaptation process methodology utilized for the generation of the first national guideline for management of people with ADHD in Saudi Arabia. Methods We used the KSU-Modified-ADAPTE methodology for the guideline adaptation process. We describe the full process in detail including the three phases of set-up, adaptation, and finalization. The process was conducted by a multidisciplinary guideline adaptation group in addition to an external review for the clinical content and methodology. Results The group adapted ten main categories of recommendations from one source CPG (NICE). The recommendations include: (i) service organisation and training, (ii) recognition, identification and referral, (iii) diagnosis, (iv) support, (v) managing ADHD, (vi) dietary advice, (vii) medication, (viii) maintenance and monitoring, (ix) adherence to treatment, and (x) review of medication and discontinuation. Several implementation tools were compiled and developed to enhance implementability including a clinical algorithm, quality measures, coding system, medication tables, translations, patient information, and online resources. Conclusions The finalized clinical practice guideline provides healthcare providers with applicable evidence-based guidance for the management of people with ADHD in Saudi Arabia. The project also demonstrated the effectiveness of KSU-Modified-ADAPTE, and emphasized the value of a collaborative clinical and methodological expert group for adaptation of national guidelines.http://deepblue.lib.umich.edu/bitstream/2027.42/173676/1/13034_2020_Article_351.pd
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