Pubmed du 16/08/14

Pubmed du jour

2014-08-16 12:03:50

1. {{International society for autism research news}}. {Autism Res}. 2014; 7(4): 526.

Lien vers le texte intégral (Open Access ou abonnement)

2. Broek JA, Guest PC, Rahmoune H, Bahn S. {{Proteomic analysis of post mortem brain tissue from autism patients: evidence for opposite changes in prefrontal cortex and cerebellum in synaptic connectivity-related proteins}}. {Mol Autism}. 2014; 5: 41.

BACKGROUND: Autism is a neurodevelopmental disorder characterized by impaired language, communication and social skills. Although genetic studies have been carried out in this field, none of the genes identified have led to an explanation of the underlying causes. Here, we have investigated molecular alterations by proteomic profiling of post mortem brain samples from autism patients and controls. The analysis focussed on prefrontal cortex and cerebellum as previous studies have found that these two brain regions are structurally and functionally connected, and they have been implicated in autism. METHODS: Post mortem prefrontal cortex and cerebellum samples from autism patients and matched controls were analysed using selected reaction monitoring mass spectrometry (SRM-MS). The main objective was to identify significantly altered proteins and biological pathways and to compare these across these two brain regions. RESULTS: Targeted SRM-MS resulted in identification of altered levels of proteins related to myelination, synaptic vesicle regulation and energy metabolism. This showed decreased levels of the immature astrocyte marker vimentin in both brain regions, suggesting a decrease in astrocyte precursor cells. Also, decreased levels of proteins associated with myelination and increased synaptic and energy-related proteins were found in the prefrontal cortex, indicative of increased synaptic connectivity. Finally, opposite directional changes were found for myelination and synaptic proteins in the cerebellum. CONCLUSION: These findings suggest altered structural and/or functional connectivity in the prefrontal cortex and cerebellum in autism patients, as shown by opposite effects on proteins involved in myelination and synaptic function. Further investigation of these findings could help to increase our understanding of the mechanisms underlying autism relating to brain connectivity, with the ultimate aim of facilitating novel therapeutic approaches.

Lien vers le texte intégral (Open Access ou abonnement)

3. Fabio RA, Colombo B, Russo S, Cogliati F, Masciadri M, Foglia S, Antonietti A, Tavian D. {{Recent insights into genotype-phenotype relationships in patients with Rett syndrome using a fine grain scale}}. {Res Dev Disabil}. 2014; 35(11): 2976-86.

Mutations in MECP2 gene cause Rett syndrome (RTT), a neurodevelopmental disorder affecting around 1 in 10,000 female births. The clinical picture of RTT appears quite heterogeneous for each single feature. Mutations in MECP2 gene have been associated with the onset of RTT. The most known gene function consists of transcriptional repression of specific target genes, mainly by the binding of its methyl binding domain (MBD) to methylated CpG nucleotides and recruiting co-repressors and histone deacetylase binding to DNA by its transcription repressor domain (TRD). This study aimed at evaluating a cohort of 114 Rett syndrome (RTT) patients with a detailed scale measuring the different kinds of impairments produced by the syndrome. The sample included relatively large subsets of the most frequent mutations, so that genotype-phenotype correlations could be tested. Results revealed that frequent missense mutations showed a specific profile in different areas of impairment. The R306C mutation, considered as producing mild impairment, was associated to a moderate phenotype in which behavioural characteristics were mainly affected. A notable difference emerged by comparing mutations truncating the protein before and after the nuclear localization signal; such a difference concerned prevalently the motor-functional and autonomy skills of the patients, affecting the management of everyday activities.

Lien vers le texte intégral (Open Access ou abonnement)

4. Foti F, De Crescenzo F, Vivanti G, Menghini D, Vicari S. {{Implicit learning in individuals with autism spectrum disorders: a meta-analysis}}. {Psychol Med}. 2014: 1-14.

BACKGROUND: Individuals with autism spectrum disorders (ASDs) are characterized by social communication difficulties and behavioural rigidity. Difficulties in learning from others are one of the most devastating features of this group of conditions. Nevertheless, the nature of learning difficulties in ASDs is still unclear. Given the relevance of implicit learning for social and communicative functioning, a link has been hypothesized between ASDs and implicit learning deficit. However, studies that have employed formal testing of implicit learning in ASDs provided mixed results. METHOD: We undertook a systematic search of studies that examined implicit learning in ASDs using serial reaction time (SRT), alternating serial reaction time (ASRT), pursuit rotor (PR), and contextual cueing (CC) tasks, and synthesized the data using meta-analysis. A total of 11 studies were identified, representing data from 407 individuals with ASDs and typically developing comparison participants. RESULTS: The results indicate that individuals with ASDs do not differ in any task considered [SRT and ASRT task: standardized mean difference (SMD) -0.18, 95% confidence interval (CI) -0.71 to 0.36; PR task: SMD -0.34, 95% CI -1.04 to 0.36; CC task: SMD 0.27, 95% CI -0.07 to 0.60]. CONCLUSIONS: Based on our synthesis of the existing literature, we conclude that individuals with ASDs can learn implicitly, supporting the hypothesis that implicit learning deficits do not represent a core feature in ASDs.

Lien vers le texte intégral (Open Access ou abonnement)

5. Hirschler-Guttenberg Y, Golan O, Ostfeld-Etzion S, Feldman R. {{Mothering, fathering, and the regulation of negative and positive emotions in high-functioning preschoolers with Autism Spectrum Disorder}}. {J Child Psychol Psychiatry}. 2014.

BACKGROUND: Children with ASD exhibit difficulties in regulating emotions and authors have called to study the specific processes underpinning emotion regulation (ER) in ASD. Yet, little observational research examined the strategies preschoolers with ASD use to regulate negative and positive emotions in the presence of their mothers and fathers. METHODS: Forty preschoolers with ASD and 40 matched typically developing children and their mothers and fathers participated. Families were visited twice for identical battery of paradigms with mother or father. Parent-child interactions were coded for parent and child behaviors and children engaged in ER paradigms eliciting negative (fear) and positive (joy) emotions with each parent. ER paradigms were microcoded for negative and positive emotionality, ER strategies, and parent regulation facilitation. RESULTS: During free play, mothers’ and fathers’ sensitivity and warm discipline were comparable across groups; however, children with ASD displayed lower positive engagement and higher withdrawal. During ER paradigms, children with ASD expressed less positive emotionality overall and more negative emotionality during fear with father. Children with ASD used more simple self-regulatory strategies, particularly during fear, but expressed comparable levels of assistance seeking behavior toward mother and father in negative and positive contexts. Parents of children with ASD used less complex regulation facilitation strategies, including cognitive reappraisal and emotional reframing, and employed simple tactics, such as physical comforting to manage fear and social gaze to maintain joy. CONCLUSION: Findings describe general and parent- and emotion-specific processes of child ER and parent regulation facilitation in preschoolers with ASD. Results underscore the ability of such children to seek parental assistance during moments of high arousal and the parents’ sensitive adaptation to their children’s needs. Reduced positive emotionality, rather than increased negative reactivity and self-regulatory efforts, emerges as the consistent element associated with ER processes in this group.

Lien vers le texte intégral (Open Access ou abonnement)

6. Kripke CC. {{Primary Care for Adolescents with Developmental Disabilities}}. {Prim Care}. 2014; 41(3): 507-18.

Disability is a natural part of the human experience. To maximize potential, adolescents with disabilities require multidisciplinary transition planning and life-skill training. Health care professionals can reduce barriers to accessing health care. They can encourage self-determination and connect patients to self-advocacy organizations. They can facilitate smooth transitions to adult health care services. Careful descriptions of a patient’s baseline traits and function are critical, not only to assist in person centered planning processes, but to ensure that new caregivers and clinicians have the information they need to recognize changes in function or behavior that can signal illness.

Lien vers le texte intégral (Open Access ou abonnement)

7. Mundalil Vasu M, Anitha A, Thanseem I, Suzuki K, Yamada K, Takahashi T, Wakuda T, Iwata K, Tsujii M, Sugiyama T, Mori N. {{Serum microRNA profiles in children with autism}}. {Mol Autism}. 2014; 5: 40.

BACKGROUND: As regulators of gene expression, microRNAs (miRNAs) play a key role in the transcriptional networks of the developing human brain. Circulating miRNAs in the serum and plasma are remarkably stable and are suggested to have promise as noninvasive biomarkers for neurological and neurodevelopmental disorders. We examined the serum expression profiles of neurologically relevant miRNAs in autism spectrum disorder (ASD), a complex neurodevelopmental disorder characterized by multiple deficits in communication, social interaction and behavior. METHODS: Total RNA, including miRNA, was extracted from the serum samples of 55 individuals with ASD and 55 age- and sex-matched control subjects, and the mature miRNAs were selectively converted into cDNA. Initially, the expression of 125 mature miRNAs was compared between pooled control and ASD samples. The differential expression of 14 miRNAs was further validated by SYBR Green quantitative PCR of individual samples. Receiver-operating characteristic (ROC) analysis was used to evaluate the sensitivity and specificity of miRNAs. The target genes and pathways of miRNAs were predicted using DIANA mirPath software. RESULTS: Thirteen miRNAs were differentially expressed in ASD individuals compared to the controls. MiR-151a-3p, miR-181b-5p, miR-320a, miR-328, miR-433, miR-489, miR-572, and miR-663a were downregulated, while miR-101-3p, miR-106b-5p, miR-130a-3p, miR-195-5p, and miR-19b-3p were upregulated. Five miRNAs showed good predictive power for distinguishing individuals with ASD. The target genes of these miRNAs were enriched in several crucial neurological pathways. CONCLUSIONS: This is the first study of serum miRNAs in ASD individuals. The results suggest that a set of serum miRNAs might serve as a possible noninvasive biomarker for ASD.

Lien vers le texte intégral (Open Access ou abonnement)

8. Pollard JS, Higbee TS, Akers JS, Brodhead MT. {{An evaluation of interactive computer training to teach instructors to implement discrete trials with children with autism}}. {J Appl Behav Anal}. 2014.

Discrete-trial instruction (DTI) is a teaching strategy that is often incorporated into early intensive behavioral interventions for children with autism. Researchers have investigated time- and cost-effective methods to train staff to implement DTI, including self-instruction manuals, video modeling, and interactive computer training (ICT). ICT combines the best components of self-instruction manuals and video models, and have the same benefits; however, there is limited research on this training method. Therefore, the purpose of this study was to investigate ICT to teach university students to implement DTI with children with autism. All participants’ teaching fidelity increased during both role-plays with an adult and instructional sessions with a child with autism. In addition, participants demonstrated an increase in teaching fidelity with untrained instructional programs. All participants were able to complete training in an average of 2 hr, and social validity ratings were high.

Lien vers le texte intégral (Open Access ou abonnement)

9. Yasuda Y, Hashimoto R, Fukai R, Okamoto N, Hiraki Y, Yamamori H, Fujimoto M, Ohi K, Taniike M, Mohri I, Nakashima M, Tsurusaki Y, Saitsu H, Matsumoto N, Miyake N, Takeda M. {{Duplication of the NPHP1 gene in patients with autism spectrum disorder and normal intellectual ability: a case series}}. {Ann Gen Psychiatry}. 2014; 13: 22.

Autism spectrum disorder is a neurodevelopmental disorder characterized by impairments in social interactions, reduced verbal communication abilities, stereotyped repetitive behaviors, and restricted interests. It is a complex condition caused by genetic and environmental factors; the high heritability of this disorder supports the presence of a significant genetic contribution. Many studies have suggested that copy-number variants contribute to the etiology of autism spectrum disorder. Recently, copy-number variants of the nephronophthisis 1 gene have been reported in patients with autism spectrum disorder. To the best of our knowledge, only six autism spectrum disorder cases with duplications of the nephronophthisis 1 gene have been reported. These patients exhibited intellectual dysfunction, including verbal dysfunction in one patient, below-average verbal intellectual ability in one patient, and intellectual disability in four patients. In this study, we identified nephronophthisis 1 duplications in two unrelated Japanese patients with autism spectrum disorder using a high-resolution single-nucleotide polymorphism array. This report is the first to describe a nephronophthisis 1 duplication in an autism spectrum disorder patient with an average verbal intelligence quotient and an average performance intelligence quotient. However, the second autism spectrum disorder patient with a nephronophthisis 1 duplication had a below-average performance intelligence quotient. Neither patient exhibited physical dysfunction, motor developmental delay, or neurological abnormalities. This study supports the clinical observation of nephronophthisis 1 duplication in autism spectrum disorder cases and might contribute to our understanding of the clinical phenotype that arises from this duplication.

Lien vers le texte intégral (Open Access ou abonnement)