Pubmed du 22/04/14

Pubmed du jour

2014-04-22 12:03:50

1. {{Neurodevelopmental disorders: Paternal obesity raises risk of autism spectrum disorders}}. {Nat Rev Neurol};2014 (Apr 22)

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2. Chen E, Sharma MR, Shi X, Agrawal RK, Joseph S. {{Fragile X Mental Retardation Protein Regulates Translation by Binding Directly to the Ribosome}}. {Mol Cell};2014 (Apr 15)
Fragile X syndrome (FXS) is the most common form of inherited mental retardation, and it is caused by loss of function of the fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein that is involved in the translational regulation of several neuronal mRNAs. However, the precise mechanism of translational inhibition by FMRP is unknown. Here, we show that FMRP inhibits translation by binding directly to the L5 protein on the 80S ribosome. Furthermore, cryoelectron microscopic reconstruction of the 80S ribosomeFMRP complex shows that FMRP binds within the intersubunit space of the ribosome such that it would preclude the binding of tRNA and translation elongation factors on the ribosome. These findings suggest that FMRP inhibits translation by blocking the essential components of the translational machinery from binding to the ribosome.

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3. Ecker C, Shahidiani A, Feng Y, Daly E, Murphy C, D’Almeida V, Deoni S, Williams SC, Gillan N, Gudbrandsen M, Wichers R, Andrews D, Van Hemert L, Murphy DG. {{The effect of age, diagnosis, and their interaction on vertex-based measures of cortical thickness and surface area in autism spectrum disorder}}. {J Neural Transm};2014 (Apr 22)
Autism spectrum disorder (ASD) is a lifelong neurodevelopmental condition that is accompanied by an atypical development of brain maturation. So far, brain development has mainly been studied during early childhood in ASD, and using measures of total or lobular brain volume. However, cortical volumetric measures are a product of two distinct biological neuroanatomical features, cortical thickness, and surface area, which most likely also have different neurodevelopmental trajectories in ASD. Here, we therefore examined age-related differences in cortical thickness and surface area in a cross-sectional sample of 77 male individuals with ASD ranging from 7 to 25 years of age, and 77 male neurotypical controls matched for age and FSIQ. Surface-based measures were analyzed using a general linear model (GLM) including linear, quadratic, and cubic age terms, as well as their interactions with the main effect of group. When controlling for the effects of age, individuals with ASD had spatially distributed reductions in cortical thickness relative to controls, particularly in fronto-temporal regions, and also showed significantly reduced surface area in the prefrontal cortex and the anterior temporal lobe. We also observed significant group x age interactions for both measures. However, while cortical thickness was best predicted by a quadratic age term, the neurodevelopmental trajectory for measures of surface area was mostly linear. Our findings suggest that ASD is accompanied by age-related and region-specific reductions in cortical thickness and surface area during childhood and early adulthood. Thus, differences in the neurodevelopmental trajectory of maturation for both measures need to be taken into account when interpreting between-group differences overall.

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4. Foley KA, Macfabe DF, Vaz A, Ossenkopp KP, Kavaliers M. {{Sexually dimorphic effects of prenatal exposure to propionic acid and lipopolysaccharide on social behavior in neonatal, adolescent, and adult rats: Implications for autism spectrum disorders}}. {Int J Dev Neurosci};2014 (Apr 18)
Emerging evidence suggests that the gut microbiome plays an important role in immune functioning, behavioral regulation and neurodevelopment. Altered microbiome composition, including altered short chain fatty acids, and/or immune system dysfunction, may contribute to neurodevelopmental disorders such as autism spectrum disorders (ASD), with some children with ASD exhibiting both abnormal gut bacterial metabolite composition and immune system dysfunction. This study describes the effects of prenatal propionic acid (PPA), a short chain fatty acid and metabolic product of many antibiotic resistant enteric bacteria, and of prenatal lipopolysaccharide (LPS), a bacterial mimetic and microbiome component, on social behavior in male and female neonatal, adolescent and adult rats. Pregnant Long-Evans rats were injected once a day with either a low level of PPA (500mg/kg SC) on gestation days G12-16, LPS (50mug/kg SC) on G12, or vehicle control on G12 or G12-16. Sex- and age-specific, subtle effects on behavior were observed. Both male and female PPA treated pups were impaired in a test of their nest seeking response, suggesting impairment in olfactory-mediated neonatal social recognition. As well, adolescent males, born to PPA treated dams, approached a novel object more than control animals and showed increased levels of locomotor activity compared to prenatal PPA females. Prenatal LPS produced subtle impairments in social behavior in adult male and female rats. These findings raise the possibility that brief prenatal exposure to elevated levels of microbiome products, such as PPA or LPS, can subtly influence neonatal, adolescent and adult social behavior.

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5. Goldman SE, Adkins KW, Calcutt MW, Carter MD, Goodpaster RL, Wang L, Shi Y, Burgess HJ, Hachey DL, Malow BA. {{Melatonin in Children with Autism Spectrum Disorders: Endogenous and Pharmacokinetic Profiles in Relation to Sleep}}. {J Autism Dev Disord};2014 (Apr 22)
Supplemental melatonin has been used to treat sleep onset insomnia in children with autism spectrum disorders (ASD), although the mechanism of action is uncertain. We assessed endogenous and supplemental melatonin profiles in relation to sleep in nine children with ASD. In endogenous samples, maximal melatonin concentration (C max) and time to peak concentration (T max) were comparable to those previously published in the literature for typically developing children, and dim light melatonin onsets were captured in the majority of children. In treatment samples (supplemental melatonin), melatonin parameters were also comparable to those previously published for typically developing children. Our findings support that children with ASD and insomnia responsive to low dose melatonin treatment have relatively normal profiles of endogenous and supplemental melatonin.

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6. Guy L, Souders M, Bradstreet L, Delussey C, Herrington JD. {{Brief Report: Emotion Regulation and Respiratory Sinus Arrhythmia in Autism Spectrum Disorder}}. {J Autism Dev Disord};2014 (Apr 22)
Emotion regulation (ER) may be an important transdiagnostic factor for understanding mental and behavioral health given its association with several psychiatric disorders, including autism spectrum disorder (ASD). However, there is limited research on ER in ASD, particularly using biomarkers such as respiratory sinus arrhythmia (RSA). The aim of the current study was to examine RSA among school-aged children with ASD in relation to symptoms of anxiety, executive functioning, and adaptive socialization skills. Results showed decreased RSA in children with ASD (relative to typically developing controls), reflecting decreased parasympathetic nervous system activity. In addition, decreased RSA was associated with increased symptoms of anxiety and lower socialization skills. These findings emphasize the need for interventions targeting emotional and arousal regulation in ASD.

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7. Hobson JA, Hobson RP, Cheung Y, Calo S. {{Symbolizing as Interpersonally Grounded Shifts in Meaning: Social Play in Children With and Without Autism}}. {J Autism Dev Disord};2014 (Apr 22)
The aim of this study was to examine the relation between symbolic play and communicative engagement among children with and without autism. Our predictions were firstly, that in moment-by-moment interactions during semi-structured interactive play with an adult, children with and without autism would tend to show shifts in meanings in symbolic play when engaged in coordinated states of joint engagement (events involving ‘sharing-of-meaning’); secondly, that across atypically developing participants, sharing-of-meaning would (a) correlate with scores on a standardized test of pretend play, and (b) be inversely correlated with scores on the Autism Diagnostic Observation Schedule; and finally, that participants with autism would contrast with matched developmentally delayed participants in manifesting lower levels of joint engagement, lower levels of symbolic play, and fewer shifts in symbolic meaning. Each of these predictions was borne out. The intimate developmental relation between social engagement and symbolic play appears to be important for explaining the developmental psychopathology of autism.

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8. Kim YS, Fombonne E, Koh YJ, Kim SJ, Cheon KA, Leventhal BL. {{A Comparison of DSM-IV Pervasive Developmental Disorder and DSM-5 Autism Spectrum Disorder Prevalence in an Epidemiologic Sample}}. {J Am Acad Child Adolesc Psychiatry};2014 (May);53(5):500-508.

OBJECTIVE: Changes in autism diagnostic criteria found in DSM-5 may affect autism spectrum disorder (ASD) prevalence, research findings, diagnostic processes, and eligibility for clinical and other services. Using our published, total-population Korean prevalence data, we compute DSM-5 ASD and social communication disorder (SCD) prevalence and compare them with DSM-IV pervasive developmental disorder (PDD) prevalence estimates. We also describe individuals previously diagnosed with DSM-IV PDD when diagnoses change with DSM-5 criteria. METHOD: The target population was all children from 7 to 12 years of age in a South Korean community (N = 55,266), those in regular and special education schools, and a disability registry. We used the Autism Spectrum Screening Questionnaire for systematic, multi-informant screening. Parents of screen-positive children were offered comprehensive assessments using standardized diagnostic procedures, including the Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule. Best-estimate clinical diagnoses were made using DSM-IV PDD and DSM-5 ASD and SCD criteria. RESULTS: DSM-5 ASD estimated prevalence was 2.20% (95% confidence interval = 1.77-3.64). Combined DSM-5 ASD and SCD prevalence was virtually the same as DSM-IV PDD prevalence (2.64%). Most children with autistic disorder (99%), Asperger disorder (92%), and PDD-NOS (63%) met DSM-5 ASD criteria, whereas 1%, 8%, and 32%, respectively, met SCD criteria. All remaining children (2%) had other psychopathology, principally attention-deficit/hyperactivity disorder and anxiety disorder. CONCLUSION: Our findings suggest that most individuals with a prior DSM-IV PDD meet DSM-5 diagnostic criteria for ASD and SCD. PDD, ASD or SCD; extant diagnostic criteria identify a large, clinically meaningful group of individuals and families who require evidence-based services.

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9. Minshawi NF, Hurwitz S, Fodstad JC, Biebl S, Morriss DH, McDougle CJ. {{The association between self-injurious behaviors and autism spectrum disorders}}. {Psychol Res Behav Manag};2014;7:125-136.

A key area of concern in children with autism spectrum disorders (ASDs) are self-injurious behaviors (SIBs). These are behaviors that an individual engages in that may cause physical harm, such as head banging, or self-biting. SIBs are more common in children with ASD than those who are typically developing or have other neurodevelopmental disabilities. Therefore, it is important that clinicians who work with children with ASD have a solid understanding of SIB. The purpose of this paper is to review the research on the epidemiology of SIB in children with ASD, factors that predict the presence of SIB in this population, and the empirically supported behavioral treatments available.

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10. Muratori F, Narzisi A. {{Exploratory study describing 6 month outcomes for young children with autism who receive treatment as usual in Italy}}. {Neuropsychiatr Dis Treat};2014;10:577-586.

BACKGROUND: In the last few years, the results of different studies have confirmed, in different ways, the importance of early intervention for autism. This study aims to evaluate the role of early « as usual » interventions in the outcome of toddlers diagnosed with autism spectrum disorder (ASD). METHOD: Seventy children with ASD aged between 24 and 48 months were recruited at different centers in Italy. They were evaluated by blind researchers at baseline and after 6 months of using Autism Diagnostic Observation Schedule-Generic (ADOS-G), Griffiths Mental Developmental Scales, and Vineland Adaptive Behavior scales. Parents filled out the MacArthur Inventory, Social Communication Questionnaire, and Child Behavior Check List. All children were referred to community providers for available interventions. RESULTS: At the endpoint, most of the children were still classified as having an ADOS-G classification of ASD. However, 21 (34.2%) passed from autism to autism spectrum, and 3 (4.2%) passed from autism spectrum to no spectrum. Treatment effects were obtained for cognitive functioning, language, adaptive behavior, and child behavior without differences between development-oriented and behavior-oriented interventions. Parent involvement was a mediator for the best clinical outcome. Baseline low impairments of communication, language comprehension, and gesture were predictors of positive outcome. CONCLUSION: Treatment as usual, composed of individual therapy plus school-supported inclusion, may be an effective intervention in ASD. Better initial levels of communication in child and parent involvement during treatment have an important role for a positive outcome.

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11. Rojas DC. {{The role of glutamate and its receptors in autism and the use of glutamate receptor antagonists in treatment}}. {J Neural Transm};2014 (Apr 22)
Glutamate is the major excitatory neurotransmitter in the brain and may be a key neurotransmitter involved in autism. Literature pertaining to glutamate and autism or related disorders (e.g., Fragile X syndrome) is reviewed in this article. Interest in glutamatergic dysfunction in autism is high due to increasing convergent evidence implicating the system in the disorder from peripheral biomarkers, neuroimaging, protein expression, genetics and animal models. Currently, there are no pharmaceutical interventions approved for autism that address glutamate deficits in the disorder. New treatments related to glutamatergic neurotransmission, however, are emerging. In addition, older glutamate-modulating medications with approved indications for use in other disorders are being investigated for re-tasking as treatments for autism. This review presents evidence in support of glutamate abnormalities in autism and the potential for translation into new treatments for the disorder.

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12. Siller M, Swanson MR, Serlin G, George A. {{Internal State Language in the Storybook Narratives of Children with and without Autism Spectrum Disorder: Investigating Relations to Theory of Mind Abilities}}. {Res Autism Spectr Disord};2014 (May 1);8(5):589-596.

The current study examines narratives elicited using a wordless picture book, focusing on language used to describe the characters’ thoughts and emotions (i.e., internal state language, ISL). The sample includes 21 children with Autism Spectrum Disorder (ASD) and 24 typically developing controls, matched on children’s gender, IQ, as well as receptive and expressive vocabulary. This research had three major findings. First, despite equivalent performance on standardized language assessments, the volume of children’s narratives (i.e., the number of utterances and words, the range of unique verbs and adjectives) was lower in children with ASD than in typically developing controls. Second, after controlling for narrative volume, the narratives of children with ASD were less likely to reference the characters’ emotions than was the case for typically developing controls. Finally, our results revealed a specific association between children’s use of emotion terms and their performance on a battery of experimental tasks evaluating children’s Theory of Mind abilities. Implications for our understanding of narrative deficits in ASD as well as interventions that use narrative as a context for improving social comprehension are discussed.

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13. Vaishnavi V, Manikandan M, Munirajan AK. {{Mining the 3’UTR of Autism-implicated Genes for SNPs Perturbing MicroRNA Regulation}}. {Genomics Proteomics Bioinformatics};2014 (Apr 16)
Autism spectrum disorder (ASD) refers to a group of childhood neurodevelopmental disorders with polygenic etiology. The expression of many genes implicated in ASD is tightly regulated by various factors including microRNAs (miRNAs), a class of noncoding RNAs approximately 22 nucleotides in length that function to suppress translation by pairing with ‘miRNA recognition elements’ (MREs) present in the 3’untranslated region (3’UTR) of target mRNAs. This emphasizes the role played by miRNAs in regulating neurogenesis, brain development and differentiation and hence any perturbations in this regulatory mechanism might affect these processes as well. Recently, single nucleotide polymorphisms (SNPs) present within 3’UTRs of mRNAs have been shown to modulate existing MREs or even create new MREs. Therefore, we hypothesized that SNPs perturbing miRNA-mediated gene regulation might lead to aberrant expression of autism-implicated genes, thus resulting in disease predisposition or pathogenesis in at least a subpopulation of ASD individuals. We developed a systematic computational pipeline that integrates data from well-established databases. By following a stringent selection criterion, we identified 9 MRE-modulating SNPs and another 12 MRE-creating SNPs in the 3’UTR of autism-implicated genes. These high-confidence candidate SNPs may play roles in ASD and hence would be valuable for further functional validation.

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14. Zalla T, Amsellem F, Chaste P, Ervas F, Leboyer M, Champagne-Lavau M. {{Individuals with autism spectrum disorders do not use social stereotypes in irony comprehension}}. {PLoS One};2014;9(4):e95568.

Social and communication impairments are part of the essential diagnostic criteria used to define Autism Spectrum Disorders (ASDs). Difficulties in appreciating non-literal speech, such as irony in ASDs have been explained as due to impairments in social understanding and in recognizing the speaker’s communicative intention. It has been shown that social-interactional factors, such as a listener’s beliefs about the speaker’s attitudinal propensities (e.g., a tendency to use sarcasm, to be mocking, less sincere and more prone to criticism), as conveyed by an occupational stereotype, do influence a listener’s interpretation of potentially ironic remarks. We investigate the effect of occupational stereotype on irony detection in adults with High Functioning Autism or Asperger Syndrome (HFA/AS) and a comparison group of typically developed adults. We used a series of verbally presented stories containing ironic or literal utterances produced by a speaker having either a « sarcastic » or a « non-sarcastic » occupation. Although individuals with HFA/AS were able to recognize ironic intent and occupational stereotypes when the latter are made salient, stereotype information enhanced irony detection and modulated its social meaning (i.e., mockery and politeness) only in comparison participants. We concluded that when stereotype knowledge is not made salient, it does not automatically affect pragmatic communicative processes in individuals with HFA/AS.

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15. Zane T, Carlson M, Estep D, Quinn M. {{Using functional assessment to treat behavior problems of deaf and hard of hearing children diagnosed with autism spectrum disorder}}. {Am Ann Deaf};2014 (Winter);158(5):555-566.

A defining feature of autism spectrum disorders is atypical behaviors, e.g., stereotypy, noncompliance, rituals, and aggression. Deaf and hard of hearing individuals with autism present a greater challenge because of additional issues related to their hearing status. One conceptualization of problem behavior is that it serves a communication function, i.e., the person has learned that certain misbehaviors may be reinforced in some way. The present article describes « functional behavior assessment, » a group of state-of-the-art methodologies that allow a caregiver to determine the cause of the behavior, so that treatment–based on that cause–will be more effective. Different methods of functional assessment are described, along with a step-by-step implementation sequence. The results of a functional assessment should lead to more effective programming, resulting in quicker elimination of the behavioral concerns, and allow the person to gain access to greater independence and more reinforcement.

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