Pubmed du 26/02/14

Pubmed du jour

2014-02-26 12:03:50

1. {{Genetics: Potassium channel function linked to autism and epilepsy}}. {Nature reviews Neurology}. 2014 Feb 25.

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2. Copple K, Koul R, Banda D, Frye E. {{An examination of the effectiveness of video modelling intervention using a speech-generating device in preschool children at risk for autism}}. {Developmental neurorehabilitation}. 2014 Feb 24.

Abstract Objective: To investigate whether preschool children at risk for autism would learn to request a preferred object using a speech-generating device (SGD) following a video modelling (VM) intervention and generalize requesting behaviours to preferred objects across stimuli and communication partners. Method: A single-subject multiple baseline design across participants (n = 3) was used to assess the effects of VM intervention on requesting behaviour. Intervention consisted of having each participant view a VM of two adults demonstrating the requesting of a preferred object using the SGD. Additionally, a least-to-most-prompting technique was employed to facilitate the production of a correct response. Results: All three participants demonstrated the ability to request preferred objects following the intervention and were able to generalize the newly acquired requesting behaviour across stimuli and people. Conclusions: Study findings indicate that a VM treatment package is effective in facilitating communication in children with little or no functional speech.

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3. Donato C, Shane HC, Hemsley B. {{Exploring the feasibility of the Visual Language in Autism program for children in an early intervention group setting: Views of parents, educators, and health professionals}}. {Developmental neurorehabilitation}. 2014 Feb 24.

Abstract Objective: To explore the views of key stakeholders on using visual supports for children with developmental disabilities in early intervention group settings. Specifically, this study aimed to determine stakeholders’ views on the barriers to and facilitators for the use of visual supports in these settings to inform the feasibility of implementing an immersive Visual Language in Autism program. Methods: This study involved three focus groups of parents, educators, and health professionals at one Australian early intervention group setting. Results: Lack of time, limited services, negative attitudes in society, and inconsistent use were cited as common barriers to using visual supports. Facilitators included having access to information and evidence on visual supports, increased awareness of visual supports, and the use of mobile technologies. Conclusion: The Visual Language in Autism program is feasible in early intervention group settings, if barriers to and facilitators for its use are addressed to enable an immersive visual language experience.

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4. Frazier TW, Georgiades S, Bishop SL, Hardan AY. {{Behavioral and cognitive characteristics of females and males with autism in the simons simplex collection}}. {Journal of the American Academy of Child and Adolescent Psychiatry}. 2014 Mar;53(3):329-40 e3.

OBJECTIVE: To examine differences in behavioral symptoms and cognitive functioning between males and females with autism spectrum disorder (ASD). METHOD: We analyzed data from 2,418 probands with autism (304 females and 2,114 males) included in the Simons Simplex Collection. Sex differences were evaluated across measures of autism symptoms, cognitive and motor functioning, adaptive behavior, and associated behavior problems. Measurement bias was examined using latent variable models of symptoms. Unadjusted and propensity-adjusted analyses were computed to ensure that sex differences were not due to unbalanced sampling. Moderator and mediator analyses evaluated whether sex differences were modified by clinical characteristics or were driven by cognitive ability. RESULTS: Females with ASD had greater social communication impairment, lower levels of restricted interests, lower cognitive ability, weaker adaptive skills, and greater externalizing problems relative to males. Symptom differences could not be accounted for by measurement differences, indicating that diagnostic instruments captured autism similarly in males and females. IQ reductions mediated greater social impairment and reduced adaptive behavior in females with ASD, but did not mediate reductions in restricted interests or increases in irritability. CONCLUSIONS: A specific female ASD phenotype is emerging that cannot be accounted for by differential symptom measurement. The present data suggest that the relatively low proportion of high-functioning females may reflect the effect of protective biological factors or may be due to under-identification. Additional carefully accrued samples are needed to confirm the present pattern and to evaluate whether observed sex ratios in high-functioning cases are reduced if female-specific indicators of restricted interests are included.

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5. Joshi G, Faraone SV, Wozniak J, Petty C, Fried R, Galdo M, Furtak SL, McDermott K, Epstien C, Walker R, Caron A, Feinberg L, Biederman J. {{Examining the Clinical Correlates of Autism Spectrum Disorder in Youth by Ascertainment Source}}. {J Autism Dev Disord}. 2014 Feb 25.

To examine whether presentation of autism spectrum disorder (ASD) and associated patterns of psychiatric comorbidity and dysfunction vary by referral source. ASD youth referred to a specialized ambulatory program for ASD (N = 143) were compared to ASD youth referred to a general child psychiatry clinic (N = 217). More ASD clinic youth met criteria for a more robust form of ASD (autistic disorder); more youth referred to the psychiatry clinic met criteria for broader spectrum ASD (pervasive developmental disorder not otherwise specified). General psychiatry clinic youth with ASD suffered from a greater burden of psychopathologies and higher levels of dysfunction. The presentation of ASD in psychiatrically referred youth differs between general and ASD-specialized clinics, though both referral populations have high levels of comorbidity and dysfunction.

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6. Kaluzna-Czaplinska J, Zurawicz E, Struck W, Markuszewski M. {{Identification of organic acids as potential biomarkers in the urine of autistic children using gas chromatography/mass spectrometry}}. {Journal of chromatography B, Analytical technologies in the biomedical and life sciences}. 2014 Feb 2.

There is a need to identify metabolic phenotypes in autism as they might each require unique approaches to prevention. Biological markers can help define autism subtypes and reveal potential therapeutic targets. The aim of the study was to identify alterations of small molecular weight compounds and to find potential biomarkers. Gas chromatography/mass spectrometry was employed to evaluate major metabolic changes in low molecular weight urine metabolites of 14 children with autism spectrum disorders vs. 10 non-autistic subjects. The results prove the usefulness of an identified set of 21 endogenous compounds (including 14 organic acids), whose levels are changed in diseased children. Gas chromatography/mass spectrometry method combined with multivariate statistical analysis techniques provide an efficient way of depicting metabolic perturbations of diseases, and may potentially be applicable as a novel strategy for the noninvasive diagnosis and treatment of autism.

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7. Koch SC, Mehl L, Sobanski E, Sieber M, Fuchs T. {{Fixing the mirrors: A feasibility study of the effects of dance movement therapy on young adults with autism spectrum disorder}}. {Autism}. 2014 Feb 24.

From the 1970s on, case studies reported the effectiveness of therapeutic mirroring in movement with children with autism spectrum disorder. In this feasibility study, we tested a dance movement therapy intervention based on mirroring in movement in a population of 31 young adults with autism spectrum disorder (mainly high-functioning and Asperger’s syndrome) with the aim to increase body awareness, social skills, self-other distinction, empathy, and well-being. We employed a manualized dance movement therapy intervention implemented in hourly sessions once a week for 7 weeks. The treatment group (n = 16) and the no-intervention control group (n = 15) were matched by sex, age, and symptom severity. Participants did not participate in any other therapies for the duration of the study. After the treatment, participants in the intervention group reported improved well-being, improved body awareness, improved self-other distinction, and increased social skills. The dance movement therapy-based mirroring approach seemed to address more primary developmental aspects of autism than the presently prevailing theory-of-mind approach. Results suggest that dance movement therapy can be an effective and feasible therapy approach for autism spectrum disorder, while future randomized control trials with bigger samples are needed.

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8. Kong SW, Sahin M, Collins CD, Wertz MH, Campbell MG, Leech JD, Krueger D, Bear MF, Kunkel LM, Kohane IS. {{Divergent dysregulation of gene expression in murine models of fragile X syndrome and tuberous sclerosis}}. {Molecular autism}. 2014 Feb 24;5(1):16.

BACKGROUND: Fragile X syndrome and tuberous sclerosis are genetic syndromes that both have a high rate of comorbidity with autism spectrum disorder (ASD). Several lines of evidence suggest that these two monogenic disorders may converge at a molecular level through the dysfunction of activity-dependent synaptic plasticity. METHODS: To explore the characteristics of transcriptomic changes in these monogenic disorders, we profiled genome-wide gene expression levels in cerebellum and blood from murine models of fragile X syndrome and tuberous sclerosis. RESULTS: Differentially expressed genes and enriched pathways were distinct for the two murine models examined, with the exception of immune response-related pathways. In the cerebellum of the Fmr1 knockout (Fmr1-KO) model, the neuroactive ligand receptor interaction pathway and gene sets associated with synaptic plasticity such as long-term potentiation, gap junction, and axon guidance were the most significantly perturbed pathways. The phosphatidylinositol signaling pathway was significantly dysregulated in both cerebellum and blood of Fmr1-KO mice. In Tsc2 heterozygous (+/-) mice, immune system-related pathways, genes encoding ribosomal proteins, and glycolipid metabolism pathways were significantly changed in both tissues. CONCLUSIONS: Our data suggest that distinct molecular pathways may be involved in ASD with known but different genetic causes and that blood gene expression profiles of Fmr1-KO and Tsc2+/- mice mirror some, but not all, of the perturbed molecular pathways in the brain.

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9. Ludlow A, Mohr B, Whitmore A, Garagnani M, Pulvermuller F, Gutierrez R. {{Auditory processing and sensory behaviours in children with autism spectrum disorders as revealed by mismatch negativity}}. {Brain and cognition}. 2014 Feb 21;86C:55-63.

Sensory dysfunctions may underlie key characteristics in children with Autism Spectrum Disorders (ASD). The current study aimed to investigate auditory change detection in children with ASD in order to determine event-related potentials to meaningless and meaningful speech stimuli. 11 high functioning boys with a diagnosis of autism spectrum disorders (mean age=13.0; SD=1.08) and 11 typically developing boys (mean age=13.7; SD=1.5) participated in a mismatch negativity (MMN) paradigm. Results revealed that compared to TD controls, the children with ASD showed significantly reduced MMN responses to both words and pseudowords in the frontal regions of the brain and also a significant reduction in their activation for words in the Central Parietal regions. In order to test the relationship between sensory processing and auditory processing, children completed the Adult and Adolescent Sensory Profile. As predicted, the children with ASD showed more extreme sensory behaviours and were significantly higher than their typically developing controls across three of the sensory quadrants (sensory sensitivity, low registration and sensory avoidance). Importantly, only auditory sensory sensitivity was able to account for the differences displayed for words in the frontal and central parietal regions when controlling for the effect of group, revealing an inverse relationship of the higher sensory sensitivity scores the less activation in response for words. We discuss how the expression of sensory behaviours in ASD may result in deficient neurophysiological mechanisms underlying automatic language processing.

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10. Navarro F, Pearson DA, Fatheree N, Mansour R, Hashmi SS, Rhoads JM. {{Are ‘leaky gut’ and behavior associated with gluten and dairy containing diet in children with autism spectrum disorders?}}. {Nutritional neuroscience}. 2014 Feb 12.

Objectives Studies have suggested a link between diet and behavior in children with autism spectrum disorders (ASDs). Parental reports of behavioral changes upon exposure to gluten and/or casein are common in clinical practice. An association between diet type, intestinal permeability (IP) (‘leaky gut’), and behavior has been long proposed but not substantiated. We explored this possible association in this trial. Methods This randomized double-blind, placebo-controlled study explored the effects of gluten and milk on IP and behavior in children with ASDs over a period of 4 weeks. IP assessed by lactulose:mannitol (L/M) sugar permeability test and behavior assessed by the Aberrant Behavior Checklist and Conners Parent Rating were measured. Gastrointestinal symptoms in both groups were also monitored. Results Neither the L/M ratio nor behavioral scores were different between groups exposed to gluten/dairy or placebo. The changes observed were noted to be small and not clinically significant. Discussion Our study although underpowered to show small differences does not support an association between dietary gluten/milk, IP, and behavioral changes in subjects with ASD.

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11. Orekhova EV, Stroganova TA. {{Arousal and attention re-orienting in autism spectrum disorders: evidence from auditory event-related potentials}}. {Frontiers in human neuroscience}. 2014;8:34.

The extended phenotype of autism spectrum disorders (ASD) includes a combination of arousal regulation problems, sensory modulation difficulties, and attention re-orienting deficit. A slow and inefficient re-orienting to stimuli that appear outside of the attended sensory stream is thought to be especially detrimental for social functioning. Event-related potentials (ERPs) and magnetic fields (ERFs) may help to reveal which processing stages underlying brain response to unattended but salient sensory event are affected in individuals with ASD. Previous research focusing on two sequential stages of the brain response-automatic detection of physical changes in auditory stream, indexed by mismatch negativity (MMN), and evaluation of stimulus novelty, indexed by P3a component,-found in individuals with ASD either increased, decreased, or normal processing of deviance and novelty. The review examines these apparently conflicting results, notes gaps in previous findings, and suggests a potentially unifying hypothesis relating the dampened responses to unattended sensory events to the deficit in rapid arousal process. Specifically, « sensory gating » studies focused on pre-attentive arousal consistently demonstrated that brain response to unattended and temporally novel sound in ASD is already affected at around 100 ms after stimulus onset. We hypothesize that abnormalities in nicotinic cholinergic arousal pathways, previously reported in individuals with ASD, may contribute to these ERP/ERF aberrations and result in attention re-orienting deficit. Such cholinergic dysfunction may be present in individuals with ASD early in life and can influence both sensory processing and attention re-orienting behavior. Identification of early neurophysiological biomarkers for cholinergic deficit would help to detect infants « at risk » who can potentially benefit from particular types of therapies or interventions.

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12. Uppal N, Gianatiempo I, Wicinski B, Schmeidler J, Heinsen H, Schmitz C, Buxbaum JD, Hof PR. {{Neuropathology of the posteroinferior occipitotemporal gyrus in children with autism}}. {Molecular autism}. 2014 Feb 24;5(1):17.

BACKGROUND: While most neuropathologic studies focus on regions involved in behavioral abnormalities in autism, it is also important to identify whether areas that appear functionally normal are devoid of pathologic alterations. In this study we analyzed the posteroinferior occipitotemporal gyrus, an extrastriate area not considered to be affected in autism. This area borders the fusiform gyrus, which is known to exhibit functional and cellular abnormalities in autism. FINDINGS: No studies have implicated posteroinferior occipitotemporal gyrus dysfunction in autism, leading us to hypothesize that neuropathology would not occur in this area. We indeed observed no significant differences in pyramidal neuron number or size in layers III, V, and VI in seven pairs of autism and controls. CONCLUSIONS: These findings are consistent with the hypothesis that neuropathology is unique to areas involved in stereotypies and social and emotional behaviors, and support the specificity of the localization of pathology in the fusiform gyrus.

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13. Urbanowicz A, Leonard H, Girdler S, Ciccone N, Downs J. {{Parental perspectives on the communication abilities of their daughters with Rett syndrome}}. {Developmental neurorehabilitation}. 2014 Feb 24.

Abstract Objective: This study describes, from the perspective of parents, how females with Rett syndrome communicate in everyday life and the barriers and facilitators to successful communication. Methods: Sixteen interviews were conducted with parents with a daughter with Rett syndrome with a pathogenic mutation in the methyl-CpG-binding protein 2 gene. Interviews were recorded and transcribed verbatim. Transcripts were analysed using directed content analysis. Results: All parents reported their daughters were able to express discomfort and pleasure, and make requests and choices using a variety of modalities including vocalisations, body movements and eye gaze. Parents also reported their daughters understood most of what they said and that the level of functional abilities, such as mobility, and environmental factors, such as characteristics of the communication partner, influenced successful communication. Conclusions: The perspectives of parents are integral to the assessment of communication abilities and have the potential to inform communication interventions for girls and women with Rett syndrome.

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14. Verly M, Verhoeven J, Zink I, Mantini D, Peeters R, Deprez S, Emsell L, Boets B, Noens I, Steyaert J, Lagae L, De Cock P, Rommel N, Sunaert S. {{Altered functional connectivity of the language network in ASD: Role of classical language areas and cerebellum}}. {NeuroImage Clinical}. 2014;4:374-82.

The development of language, social interaction and communicative skills is remarkably different in the child with autism spectrum disorder (ASD). Atypical brain connectivity has frequently been reported in this patient population. However, the neural correlates underlying their disrupted language development and functioning are still poorly understood. Using resting state fMRI, we investigated the functional connectivity properties of the language network in a group of ASD patients with clear comorbid language impairment (ASD-LI; N = 19) and compared them to the language related connectivity properties of 23 age-matched typically developing children. A verb generation task was used to determine language components commonly active in both groups. Eight joint language components were identified and subsequently used as seeds in a resting state analysis. Interestingly, both the interregional and the seed-based whole brain connectivity analysis showed preserved connectivity between the classical intrahemispheric language centers, Wernicke’s and Broca’s areas. In contrast however, a marked loss of functional connectivity was found between the right cerebellar region and the supratentorial regulatory language areas. Also, the connectivity between the interhemispheric Broca regions and modulatory control dorsolateral prefrontal region was found to be decreased. This disruption of normal modulatory control and automation function by the cerebellum may underlie the abnormal language function in children with ASD-LI.

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15. Walton KM, Ingersoll BR. {{The influence of maternal language responsiveness on the expressive speech production of children with autism spectrum disorders: A microanalysis of mother-child play interactions}}. {Autism}. 2014 Feb 24.

Adult responsiveness is related to language development both in young typically developing children and in children with autism spectrum disorders, such that parents who use more responsive language with their children have children who develop better language skills over time. This study used a micro-analytic technique to examine how two facets of maternal utterances, relationship to child focus of attention and degree of demandingness, influenced the immediate use of appropriate expressive language of preschool-aged children with autism spectrum disorders (n = 28) and toddlers with typical development (n = 16) within a naturalistic mother-child play session. Mothers’ use of follow-in demanding language was most likely to elicit appropriate expressive speech in both children with autism spectrum disorders and children with typical development. For children with autism spectrum disorders, but not children with typical development, mothers’ use of orienting cues conferred an additional benefit for expressive speech production. These findings are consistent with the naturalistic behavioral intervention philosophy and suggest that following a child’s lead while prompting for language is likely to elicit speech production in children with autism spectrum disorders and children with typical development. Furthermore, using orienting cues may help children with autism spectrum disorders to verbally respond.

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16. Wink LK, Early M, Schaefer T, Pottenger A, Horn P, McDougle CJ, Erickson CA. {{Body Mass Index Change in Autism Spectrum Disorders: Comparison of Treatment with Risperidone and Aripiprazole}}. {Journal of child and adolescent psychopharmacology}. 2014 Feb 24.

Abstract Objective: The purpose of this study was to assess change in body mass index (BMI) and age- and gender-adjusted BMI Z-score in subjects ages 2-20 years with autism spectrum disorders (ASD), who were treated longitudinally with risperidone or aripiprazole at a tertiary care ASD clinic. Method: As part of a larger project involving longitudinal drug treatment data in ASD, detailed demographic and treatment data were collected for 142 subjects ages 2-20 years who had been started on risperidone or aripiprazole for treatment of irritability. Mean age at start of treatment, treatment duration, final Clinical Global Impressions-Improvement Scale score, BMI change per year of treatment, and BMI Z-score change per year of treatment (primary outcome measure) were calculated for each drug treatment group. Group means were compared using t tests and Wilcoxon rank sum tests. Results: There was a statistically significant BMI and BMI Z-score increase in the risperidone and aripiprazole treatment groups individually. No statistically significant difference between the two treatment groups was noted in mean BMI change per year of treatment or BMI Z-score change per year of treatment. Conclusions: In our review of long-term naturalistic treatment of irritability using risperidone versus aripiprazole in persons with ASD, a significant increase in both BMI and age- and gender-adjusted BMI Z-score was noted for each treatment group. No significant difference in BMI or BMI Z-score change was noted when the two treatment groups were compared. We conclude that in our patient population at a tertiary care ASD clinic, the effects of risperidone and aripiprazole on body weight gain in naturalistic long-term treatment are no different.

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17. Xu X, Xiong Z, Zhang L, Liu Y, Lu L, Peng Y, Guo H, Zhao J, Xia K, Hu Z. {{Variations analysis of NLGN3 and NLGN4X gene in Chinese autism patients}}. {Molecular biology reports}. 2014 Feb 26.

Autism is a neurodevelopmental disorder clinically characterized by impairment of social interaction, deficits in verbal communication, as well as stereotypic and repetitive behaviors. Several studies have implicated that abnormal synaptogenesis was involved in the incidence of autism. Neuroligins are postsynaptic cell adhesion molecules and interacted with neurexins to regulate the fine balance between excitation and inhibition of synapses. Recently, mutation analysis, cellular and mice models hinted neuroligin mutations probably affected synapse maturation and function. In this study, four missense variations [p.G426S (NLGN3), p.G84R (NLGN4X), p.Q162 K (NLGN4X) and p.A283T (NLGN4X)] in four different unrelated patients have been identified by PCR and direct sequencing. These four missense variations were absent in the 453 controls and have not been reported in 1000 Genomes Project. Bioinformatic analysis of the four missense variations revealed that p.G84R and p.A283T were « Probably Damaging ». The variations may cause abnormal synaptic homeostasis and therefore trigger the patients more predisposed to autism. By case-control analysis, we identified the common SNPs (rs3747333 and rs3747334) in the NLGN4X gene significantly associated with risk for autism [p = 5.09E-005; OR 4.685 (95 % CI 2.073-10.592)]. Our data provided a further evidence for the involvement of NLGN3 and NLGN4X gene in the pathogenesis of autism in Chinese population.

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