Pubmed du 29/05/13

Pubmed du jour

2013-05-29 12:03:50

1. Adamo N, Huo L, Adelsberg S, Petkova E, Castellanos FX, Di Martino A. {{Response time intra-subject variability: commonalities between children with autism spectrum disorders and children with ADHD}}. {Eur Child Adolesc Psychiatry};2013 (May 29)

Despite the common co-occurrence of symptoms of attention deficit hyperactivity disorder (ADHD) in individuals with autism spectrum disorders (ASD), the underlying mechanisms are under-explored. A potential candidate for investigation is response time intra-subject variability (RT-ISV), a hypothesized marker of attentional lapses. Direct comparisons of RT-ISV in ASD versus ADHD are limited and contradictory. We aimed to examine whether distinct fluctuations in RT-ISV characterize children with ASD and with ADHD relative to typically developing children (TDC). We applied both a priori-based and data-driven strategies to RT performance of 46 children with ASD, 46 with ADHD, and 36 TDC (aged 7-11.9 years). Specifically, we contrasted groups relative to the amplitude of four preselected frequency bands as well as to 400 frequency bins from 0.006 to 0.345 Hz. In secondary analyses, we divided the ASD group into children with and without substantial ADHD symptoms (ASD+ and ASD-, respectively). Regardless of the strategy employed, RT-ISV fluctuations at frequencies between 0.20 and 0.345 Hz distinguished children with ADHD, but not children with ASD, from TDC. Children with ASD+ and those with ADHD shared elevated amplitudes of RT-ISV fluctuations in frequencies between 0.18 and 0.345 Hz relative to TDC. In contrast, the ASD- subgroup did not differ from TDC in RT-ISV frequency fluctuations. RT-ISV fluctuations in frequencies 0.18-0.345 Hz (i.e., periods between 3 and 5 s) are associated with ADHD symptoms regardless of categorical diagnosis and may represent a biomarker. These results suggest that children with ADHD and those with ASD+ share common underlying pathophysiological mechanisms of RT-ISV.

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2. Battaglia A, Doccini V, Bernardini L, Novelli A, Loddo S, Capalbo A, Filippi T, Carey JC. {{Confirmation of chromosomal microarray as a first-tier clinical diagnostic test for individuals with developmental delay, intellectual disability, autism spectrum disorders and dysmorphic features}}. {Eur J Paediatr Neurol};2013 (May 24)

BACKGROUND AND OBJECTIVES: Submicroscopic chromosomal rearrangements are the most common identifiable causes of intellectual disability and autism spectrum disorders associated with dysmorphic features. Chromosomal microarray (CMA) can detect copy number variants <1 Mb and identifies size and presence of known genes. The aim of this study was to demonstrate the usefulness of CMA, as a first-tier tool in detecting the etiology of unexplained intellectual disability/autism spectrum disorders (ID/ASDs) associated with dysmorphic features in a large cohort of pediatric patients. PATIENTS AND METHODS: We studied 349 individuals; 223 males, 126 females, aged 5 months-19 years. Blood samples were analyzed with CMA at a resolution ranging from 1 Mb to 40 Kb. The imbalance was confirmed by FISH or qPCR. We considered copy number variants (CNVs) causative if the variant was responsible for a known syndrome, encompassed gene/s of known function, occurred de novo or, if inherited, the parent was variably affected, and/or the involved gene/s had been reported in association with ID/ASDs in dedicated databases. RESULTS: 91 CNVs were detected in 77 (22.06%) patients: 5 (6.49%) of those presenting with borderline cognitive impairment, 54 (70.13%) with a variable degree of DD/ID, and 18/77 (23.38%) with ID of variable degree and ASDs. 16/77 (20.8%) patients had two different rearrangements. Deletions exceeded duplications (58 versus 33); 45.05% (41/91) of the detected CNVs were de novo, 45.05% (41/91) inherited, and 9.9% (9/91) unknown. The CNVs caused the phenotype in 57/77 (74%) patients; 12/57 (21.05%) had ASDs/ID, and 45/57 (78.95%) had DD/ID. CONCLUSIONS: Our study provides further evidence of the high diagnostic yield of CMA for genetic testing in children with unexplained ID/ASDs who had dysmorphic features. We confirm the value of CMA as the first-tier tool in the assessment of those conditions in the pediatric setting.

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3. Claudia S, Giuseppe B, Alessandra P, Franco C, Silvia L, Cinzia S, Lucia C, Claudio DF, Joussef H, Giuseppe V. {{Scavenger Receptor B1 Post-translational Modifications in Rett Syndrome}}. {FEBS Lett};2013 (May 24)

The modulation of the HDL receptor Scavenger Receptor B1 (SRB1) was evaluated in skin fibroblasts isolated from patients with Rett syndrome (RTT), a genetic form of infantile autism. Patients showed an altered plasma lipid profile, while their skin fibroblasts showed a dramatic reduction in SRB1 (immunogold, Western blot and immunohistochemistry). The decreased SRB1 levels were demonstrated to be the consequence of its binding with 4-hydroxy-2-nonenal (4HNE), a product of lipid peroxidation, and its increased ubiquitination. Our findings show for the first time a loss of SRB1 in RTT cells and its relationship with a chronic oxidative stress status.

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4. Jacobs DW, Richdale AL. {{Predicting literacy in children with a high-functioning autism spectrum disorder}}. {Res Dev Disabil};2013 (May 24);34(8):2379-2390.

The most commonly reported reading profile for children with a high-functioning autism spectrum disorder (HFASD) is one of intact decoding combined with reduced reading comprehension. Whether or not the variables that predict decoding and reading comprehension for children with a HFASD are exactly the same as those identified for a non-ASD population is unknown. Therefore, the ability of cognition, phonological processing, oral language, and vision to predict decoding and reading comprehension was investigated. Regression analysis revealed that cognition, phonological processing, and syntax predicted decoding and reading comprehension for the HFASD and non-ASD groups. One notable difference was that semantics predicted literacy for the non-ASD children but not their HFASD peers.

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5. Kalas A. {{Joint attention responses of children with autism spectrum disorder to simple versus complex music}}. {J Music Ther};2012 (Winter);49(4):430-452.

BACKGROUND: Joint attention deficits are viewed as one of the earliest manifestations and most characteristic features of the social deficits in Autism Spectrum Disorder (ASD). PURPOSE: The purpose of this study was to examine the effect of simple versus complex music on joint attention of children with ASD. METHOD: Thirty children with a diagnosis of ASD participated in this study. Fifteen of the participants were diagnosed with severe ASD and 15 were diagnosed with mild/moderate ASD. Each participant took part in six, 10-minute individual music conditions (3 simple & 3 complex) over a 3-week period. Each condition was designed to elicit responses to joint attention. Results: Results indicated a statistically significant interaction between music modality and functioning level. Therefore, the effect of simple versus complex music was dependent on functioning level. Specifically, the Simple Music Condition was more effective in eliciting Responses to Joint Attention (RJA) for children diagnosed with severe ASD, whereas the Complex Music Condition was more effective in eliciting RJA for children diagnosed with mild/moderate ASD. CONCLUSIONS: The results of the present study indicate that for children in the severe range of functioning, music that is simple, with clear and predictable pattems, may be most effective in eliciting responses to bids for joint attention. On the contrary, for children in the mild/moderate range of functioning, music that is more complex and variable may be most effective in eliciting responses to bids for joint attention. These results demonstrate that careful manipulation of specific musical elements can help provide the optimal conditions for facilitating joint attention with children with ASD.

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6. Ribeiro TC, Valasek CA, Minati L, Boggio PS. {{Altered semantic integration in autism beyond language: a cross-modal event-related potentials study}}. {Neuroreport};2013 (May 29);24(8):414-418.

Autism spectrum disorders (ASDs) are characterized by impaired communication, particularly pragmatic and semantic language, resulting in verbal comprehension deficits. Semantic processing in these conditions has been studied extensively, but mostly limited only to linguistic material. Emerging evidence, however, suggests that semantic integration deficits may extend beyond the verbal domain. Here, we explored cross-modal semantic integration using visual targets preceded by musical and linguistic cues. Particularly, we have recorded the event-related potentials to evaluate whether the N400 and late positive potential (LPP) components, two widely studied electrophysiological markers of semantic processing, are differently sensitive to congruence with respect to typically developing children. Seven ASD patients and seven neurotypical participants matched by age, education and intelligence quotient provided usable data. Neuroelectric activity was recorded in response to visual targets that were related or unrelated to a preceding spoken sentence or musical excerpt. The N400 was sensitive to semantic congruence in the controls but not the patients, whereas the LPP showed a complementary pattern. These results suggest that semantic processing in ASD children is also altered in the context of musical and visual stimuli, and point to a functional decoupling between the generators of the N400 and LPP, which may indicate delayed semantic processing. These novel findings underline the importance of exploring semantic integration across multiple modalities in ASDs and provide motivation for further investigation in large clinical samples.

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7. Ruiz-Robledillo N, Moya-Albiol L. {{Self-reported health and cortisol awakening response in parents of people with asperger syndrome: The role of trait anger and anxiety, coping and burden}}. {Psychol Health};2013 (May 29)

Caring for offspring with autism spectrum disorders entails high levels of stress for a long period of time and is associated with several types of health complaints. Few studies have focused on specific effects of particular disorders in the spectrum. This study was carried out with the aim of evaluating the global health of parents of people with Asperger syndrome (N = 53) compared to those of typically developing children (N = 54) through self-reported measures (medication consumption and somatic symptoms) and biological markers (cortisol awakening response [CAR]). Additionally, we analysed various psychological variables as potential predictors of caregiver health. We found that caregivers take more medication and have worse self-reported health than controls, but there were no significant differences in CAR between the groups. However, after controlling for negative affect, differences between groups in CAR reached significance. With regards to predictor variables, anxiety trait, cognitive-coping style, burden and anger temperament were significantly associated with caregiver’s self-reported health. These findings underline the need to develop interventions that foster improvements in the health of caregivers, reduce their burden and enhance their quality of life.

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8. Sowers LP, Loo L, Wu Y, Campbell E, Ulrich JD, Wu S, Paemka L, Wassink T, Meyer K, Bing X, El-Shanti H, Usachev YM, Ueno N, Manak RJ, Shepherd AJ, Ferguson PJ, Darbro BW, Richerson GB, Mohapatra DP, Wemmie JA, Bassuk AG. {{Disruption of the non-canonical Wnt gene PRICKLE2 leads to autism-like behaviors with evidence for hippocampal synaptic dysfunction}}. {Mol Psychiatry};2013 (May 28)

Autism spectrum disorders (ASDs) have been suggested to arise from abnormalities in the canonical and non-canonical Wnt signaling pathways. However, a direct connection between a human variant in a Wnt pathway gene and ASD-relevant brain pathology has not been established. Prickle2 (Pk2) is a post-synaptic non-canonical Wnt signaling protein shown to interact with post-synaptic density 95 (PSD-95). Here, we show that mice with disruption in Prickle2 display behavioral abnormalities including altered social interaction, learning abnormalities and behavioral inflexibility. Prickle2 disruption in mouse hippocampal neurons led to reductions in dendrite branching, synapse number and PSD size. Consistent with these findings, Prickle2 null neurons show decreased frequency and size of spontaneous miniature synaptic currents. These behavioral and physiological abnormalities in Prickle2 disrupted mice are consistent with ASD-like phenotypes present in other mouse models of ASDs. In 384 individuals with autism, we identified two with distinct, heterozygous, rare, non-synonymous PRICKLE2 variants (p.E8Q and p.V153I) that were shared by their affected siblings and inherited paternally. Unlike wild-type PRICKLE2, the PRICKLE2 variants found in ASD patients exhibit deficits in morphological and electrophysiological assays. These data suggest that these PRICKLE2 variants cause a critical loss of PRICKLE2 function. The data presented here provide new insight into the biological roles of Prickle2, its behavioral importance, and suggest disruptions in non-canonical Wnt genes such as PRICKLE2 may contribute to synaptic abnormalities underlying ASDs.Molecular Psychiatry advance online publication, 28 May 2013; doi:10.1038/mp.2013.71.

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