Type Of Neurodevelopmental Disorder Research Articles

Expression and Roles of Teneurins in Zebrafish.

The teneurins, also known as Ten-m/Odz, are highly conserved type II transmembrane glycoproteins widely expressed throughout the nervous system. Functioning as dimers, these large cell-surface adhesion proteins play a key role in regulating neurodevelopmental processes such as axon targeting, synaptogenesis and neuronal wiring. Synaptic specificity is driven by molecular interactions, which can occur either in a trans-homophilic manner between teneurins or through a trans-heterophilic interaction across the synaptic cleft between teneurins and other cell-adhesion molecules, such as latrophilins. The significance of teneurins interactions during development is reflected in the widespread expression pattern of the four existing paralogs across interconnected regions of the nervous system, which we demonstrate here via in situ hybridization and the generation of transgenic BAC reporter lines in zebrafish. Focusing on the visual system, we will also highlight the recent developments that have been made in furthering our understanding of teneurin interactions and their functionality, including the instructive role of teneurin-3 in specifying the functional wiring of distinct amacrine and retinal ganglion cells in the vertebrate visual system underlying a particular functionality. Based on the distinct expression pattern of all teneurins in different retinal cells, it is conceivable that the combination of different teneurins is crucial for the generation of discrete visual circuits. Finally, mutations in all four human teneurin genes have been linked to several types of neurodevelopmental disorders. The opportunity therefore arises that findings about the roles of zebrafish teneurins or their orthologs in other species shed light on the molecular mechanisms in the etiology of such human disorders.

Maternal Thyroid Function in Early Pregnancy and Child Neurodevelopmental Disorders: A Danish Nationwide Case-Cohort Study.

Maternal thyroid dysfunction may adversely affect fetal brain development, but more evidence is needed to refine this hypothesis. The aim of this study was to evaluate potential fetal programming by abnormal maternal thyroid function on child neurodevelopmental disorders. The design was a case-cohort study within the Danish National Birth Cohort (1997-2003). From the eligible cohort of 71,706 women, a random 12% sub-cohort (n = 7624) was selected, and all women (n = 2276) whose child was diagnosed with seizures, specific developmental disorder (SDD), autism spectrum disorder (ASD), and/or attention-deficit/hyperactivity disorder (ADHD) up to December 31, 2010, were identified. All women had a blood sample drawn in early pregnancy (median week 9), and the stored sample was used for measurement of free thyroxine and thyrotropin. Method- and week-specific reference ranges were used for classification of maternal thyroid function. A weighted Cox proportional hazards model was used to estimate adjusted hazard ratio (aHR) with 95% confidence intervals (CI) for neurodevelopmental disorders in children exposed to maternal thyroid dysfunction. The overall frequency of abnormal maternal thyroid function was 12.5% in the sub-cohort and significantly higher among cases of ASD (17.9%; aHR = 1.5 [CI 1.1-2.1]), but not among other types of neurodevelopmental disorders (febrile seizures: 12.7%; epilepsy: 13.1%; SDD: 12.6%; and ADHD: 14.0%). However, evaluation of subtypes of maternal thyroid dysfunction showed that maternal overt hypothyroidism (thyrotropin >10 mIU/L) was a risk factor for epilepsy in the child (aHR = 3.5 [CI 1.2-10]), as was overt hyperthyroidism for cases diagnosed within the first year of life (aHR = 3.0 [CI 1.03-8.4]). Furthermore, both maternal hypothyroidism (aHR = 1.8 [CI 1.1-2.7]) and overt hyperthyroidism (aHR = 2.2 [CI 1.1-4.4]) were risk factors for ASD in the child, and isolated low free thyroxine was associated with ASD (aHR = 4.9 [CI 2.03-11.9]) and ADHD (aHR = 2.3 [CI 1.2-4.3]) in girls but not in boys. Abnormal maternal thyroid function in early pregnancy was associated with epilepsy, ASD, and ADHD in the child, but associations differed by subtypes of exposure and by child age and sex. More evidence on subtypes and severity of maternal thyroid function is needed, and alternative outcomes of child neurodevelopment may be warranted.

Visuospatial and Verbal Short-Term Memory Correlates of Vocabulary Ability in Preschool Children.

Recent studies indicate that school-age children's patterns of performance on measures of verbal and visuospatial short-term memory (STM) and working memory (WM) differ across types of neurodevelopmental disorders. Because these disorders are often characterized by early language delay, administering STM and WM tests to toddlers could improve prediction of neurodevelopmental outcomes. Toddler-appropriate verbal, but not visuospatial, STM and WM tasks are available. A toddler-appropriate visuospatial STM test is introduced. Tests of verbal STM, visuospatial STM, expressive vocabulary, and receptive vocabulary were administered to 92 English-speaking children aged 2-5 years. Mean test scores did not differ for boys and girls. Visuospatial and verbal STM scores were not significantly correlated when age was partialed out. Age, visuospatial STM scores, and verbal STM scores accounted for unique variance in expressive (51%, 3%, and 4%, respectively) and receptive vocabulary scores (53%, 5%, and 2%, respectively) in multiple regression analyses. Replication studies, a fuller test battery comprising visuospatial and verbal STM and WM tests, and a general intelligence test are required before exploring the usefulness of these STM tests for predicting longitudinal outcomes. The lack of an association between the STM tests suggests that the instruments have face validity and test independent STM skills.

Assessing the quality of the OPQ’s Guidelines for the Evaluation of Dyslexia in Children using the Appraisal of Guidelines for Research and Evaluation (AGREE) II: A brief report.

Children with dyslexia have difficulties processing language in the areas of reading, writing, and spelling (Lyon, Shaywitz, & Shaywitz, 2003). The Diagnostic and Statistical Manual of Mental Disorders (5th ed.; American Psychiatric Association, 2013) classifies dyslexia as a specific learning disability and considers it to be a type of neurodevelopmental disorder. The Diagnostic and Statistical Manual of Mental Disorders, fifth edition, reports that the prevalence of dyslexia in school-age children is between 3% and 5%, whereas other studies found the prevalence to be between 5% and 15% (Daniel et al., 2006). It is estimated that 80-90% of learning difficulties present themselves in the school system (Leach, Scarborough, & Rescorla, 2003; Lerner, 1989; Lyon et al., 2001). Psychologists in both school and clinical settings may benefit from high-quality professional practice guidelines because they are expected to provide scientifically based recommendations to guide service delivery.The Quebec Order of Psychologists (OPQ), a prolific producer of practice guidelines, published the Guidelines for the evaluation of dyslexia in children (Lignes directrices pour l'evaluation de la dyslexie chez les enfants) in 2014. The production of this guideline began in 2009 with the participation of multiple experts. This 48-page document provides background information on dyslexia and describes so-called best practices for the evaluation of the condition, including the administration of tests. The guideline's stated objectives are to do the following: (a) to encourage rigorous methods that reflect the most up-to-date research; (b) to propose a standardized methodology based on diagnostic consensus; and (c) to identify the specific needs of children affected by dyslexia for support and accommodation (Ordre des psychologues du Quebec [OPQ], 2014).Although such objectives are both important and laudable, the availability of practice guidelines alone does not automatically lead to improved practices or health outcomes (Bergman, 1999; Cabana et al., 1999; Sackett, Rosenberg, Gray, Haynes, & Richardson, 1996; Ward & Grieco, 1996). The potential benefit of a guideline is only as good as the quality of the guideline itself (Burgers, Cluzeau, Hanna, Hunt, & Grol, 2003; Gordon & Cooper, 2010), and appropriate methodologies and rigorous strategies in the guideline development process are important for the successful dissemination and implementation of the clinical recommendations contained in the guideline (Alonso-Coello et al., 2010; Ansari & Rashidian, 2012; Blozik et al., 2012; Cahill & Heyland, 2010; Davis & Taylor-Vaisey, 1997; Grol, 2001; Norris, Holmer, Ogden, & Burda, 2011; Steinert, Richter, & Bergk, 2010). Unfortunately, in recent years, there has been a large volume of guidelines published in which the methodologies used to design the guidelines were inadequately described within the guideline or in related documents made available to professionals and service users (e.g., Rosenfeld, Shiffman, & Robertson, 2013; Stamoulos, Reyes, Trepanier, & Drapeau, 2014). For example, a description of the methods used to gather evidence and formulate recommendations, and whether the guideline was externally reviewed by experts prior to its publication, are considered minimal standards for the proLyane duction of quality guidelines (Brouwers et al., 2010; Burgers, Cluzeau, Hanna, Hunt, & Grol, 2003).The quality of practice guidelines has indeed been closely scrutinized over the past 15 years, especially in the United States and Europe, with reports of high variability in quality, many of which were cited as poor (Graham, Beardall, Carter, Tetroe, & Davies, 2003; Ruszczynski, Horvath, Dziechciarz, & Szajewska, 2016; Shaneyfelt, Mayo-Smith, & Rothwangl, 1999; Stamoulos, Reyes, Trepanier, & Drapeau, 2014). These studies raise concerns about the quality of the guidelines that are available to practitioners, about the value of the advice and recommendations they contain, and ultimately about the quality of the services received by patients and clients. …

EEG-Based Computer Aided Diagnosis of Autism Spectrum Disorder Using Wavelet, Entropy, and ANN.

Autism spectrum disorder (ASD) is a type of neurodevelopmental disorder with core impairments in the social relationships, communication, imagination, or flexibility of thought and restricted repertoire of activity and interest. In this work, a new computer aided diagnosis (CAD) of autism ‎based on electroencephalography (EEG) signal analysis is investigated. The proposed method is based on discrete wavelet transform (DWT), entropy (En), and artificial neural network (ANN). DWT is used to decompose EEG signals into approximation and details coefficients to obtain EEG subbands. The feature vector is constructed by computing Shannon entropy values from each EEG subband. ANN classifies the corresponding EEG signal into normal or autistic based on the extracted features. The experimental results show the effectiveness of the proposed method for assisting autism diagnosis. A receiver operating characteristic (ROC) curve metric is used to quantify the performance of the proposed method. The proposed method obtained promising results tested using real dataset provided by King Abdulaziz Hospital, Jeddah, Saudi Arabia.

A 12p13 GRIN2B deletion is associated with developmental delay and macrocephaly

N-methyl D-aspartate receptor subtype 2B (GluN2B), encoded by GRIN2B, is one of the components of the N-methyl D-aspartate receptor protein. Aberrations in GRIN2B have been reported to be responsible for various types of neurodevelopmental disorders. We report a Japanese boy with an ~2 Mb interstitial deletion in 12p13 involving the entire GRIN2B gene, who presented with intellectual disability, motor developmental delay and marked macrocephaly.

Parenting stress among parents of children with Neurodevelopmental Disorders

In recent years, studies have shown that parents of children with Neurodevelopmental Disorders (NDDs) experience more parenting stress than parents of typically developing children, but the relation between the type of disorders and parenting stress is far from clear. The purpose of this study was to compare the parenting stress experienced by parents of 239 children with Specific Learning Disorders (SpLD), Language Disorders (LD), Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD), and typical development (TD). Parents of children with NDDs experience more parenting stress than those of children who have TD. Although, parents of children with ASD or ADHD report the most high scores of parenting stress, also the parents of children with SpLD or LD report higher parental stress compared with parent of children without NDDs. Another interesting finding was that IQ level or emotional and behavioral problems are associated with the higher levels of parenting stress. This study suggest that parent, both mothers and fathers, of children with different type of NDDs should be provided with interventions and resources to empower them with the knowledge and skills to reduce their stress and to enhance their quality of life.

Updated findings on neurodevelopmental disorders in Taiwan

The aim of this study is to review articles published between June 2014 and 2015 that report research on neurodevelopmental disorders in both children and adults living in Taiwan. The most common of the major neurodevelopmental disorders that cause neuropsychiatric or various behavior problems in children are attention deficit hyperactivity disorder, autism spectrum disorder (ASD), Asperger syndrome, and cerebral palsy. The review examines articles written by authors from Taiwan and published in professional journals from June 2014 to 2015. About 146 articles were accessed, but only the 23 articles that address general trends in the prevalence of, and the prescription of drugs and treatment for, neurocognitive disorders are included in this review. Nearly 95% of these studies used data from the Taiwan National Health Insurance database. Most of the remaining 5% obtained their data from field work, laboratory experiments, or examination of human tissue. The reviewed publications indicate increases in the prevalence of attention deficit hyperactivity disorder, autism spectrum disorder, and other types of neurodevelopmental disorders in children living in Taiwan, from less than 1.3% in the early 1990s to nearly 3% today. The findings also indicate that drugs are very frequently prescribed to stabilize emotional and behavior problems in school age children up to age 13 and in adults with intellectual disabilities. Early onset and indicators of dementia have been two major areas of research with adults with intellectual disabilities, but so far results have been inconclusive.

Niemann-Pick Disease Type C Presenting as a Developmental Coordination Disorder with Bullying by Peers in a School-Age Child.

Niemann-Pick disease type C (NPC) is a rare progressive neurodegenerative disorder, often with onset after normal early childhood development. Juvenile onset NPC patients slowly develop cerebellar symptoms and cognitive impairment and often experience difficulties at school. However, these problems may be overlooked due to the unpublicized nature of NPC, given that it is a rare metabolic disorder. In this report, we present an 11-year-old male NPC patient, who suffered from clumsiness and difficulties in attention and academic and social skills. His symptoms were initially considered to be due to developmental coordination disorder (DCD) coexisting with bullying by peers. DCD is a type of neurodevelopmental disorder defined according to DSM-IV and is characterized by clumsiness that interferes with academic achievement and social integration not due to other general medical conditions. However, a detailed investigation of the patient suggested that the problems could be attributed to the onset of NPC. Clinicians should keep neurodegenerative disorders as differential diagnosis of children with multiple school problems.