1. Alcantara D, Timms AE, Gripp K, Baker L, Park K, Collins S, Cheng C, Stewart F, Mehta SG, Saggar A, Sztriha L, Zombor M, Caluseriu O, Mesterman R, Van Allen MI, Jacquinet A, Ygberg S, Bernstein JA, Wenger AM, Guturu H, Bejerano G, Gomez-Ospina N, Lehman A, Alfei E, Pantaleoni C, Conti V, Guerrini R, Moog U, Graham JM, Jr., Hevner R, Dobyns WB, O’Driscoll M, Mirzaa GM. {{Mutations of AKT3 are associated with a wide spectrum of developmental disorders including extreme megalencephaly}}. {Brain}. 2017; 140(10): 2610-22.
Mutations of genes within the phosphatidylinositol-3-kinase (PI3K)-AKT-MTOR pathway are well known causes of brain overgrowth (megalencephaly) as well as segmental cortical dysplasia (such as hemimegalencephaly, focal cortical dysplasia and polymicrogyria). Mutations of the AKT3 gene have been reported in a few individuals with brain malformations, to date. Therefore, our understanding regarding the clinical and molecular spectrum associated with mutations of this critical gene is limited, with no clear genotype-phenotype correlations. We sought to further delineate this spectrum, study levels of mosaicism and identify genotype-phenotype correlations of AKT3-related disorders. We performed targeted sequencing of AKT3 on individuals with these phenotypes by molecular inversion probes and/or Sanger sequencing to determine the type and level of mosaicism of mutations. We analysed all clinical and brain imaging data of mutation-positive individuals including neuropathological analysis in one instance. We performed ex vivo kinase assays on AKT3 engineered with the patient mutations and examined the phospholipid binding profile of pleckstrin homology domain localizing mutations. We identified 14 new individuals with AKT3 mutations with several phenotypes dependent on the type of mutation and level of mosaicism. Our comprehensive clinical characterization, and review of all previously published patients, broadly segregates individuals with AKT3 mutations into two groups: patients with highly asymmetric cortical dysplasia caused by the common p.E17K mutation, and patients with constitutional AKT3 mutations exhibiting more variable phenotypes including bilateral cortical malformations, polymicrogyria, periventricular nodular heterotopia and diffuse megalencephaly without cortical dysplasia. All mutations increased kinase activity, and pleckstrin homology domain mutants exhibited enhanced phospholipid binding. Overall, our study shows that activating mutations of the critical AKT3 gene are associated with a wide spectrum of brain involvement ranging from focal or segmental brain malformations (such as hemimegalencephaly and polymicrogyria) predominantly due to mosaic AKT3 mutations, to diffuse bilateral cortical malformations, megalencephaly and heterotopia due to constitutional AKT3 mutations. We also provide the first detailed neuropathological examination of a child with extreme megalencephaly due to a constitutional AKT3 mutation. This child has one of the largest documented paediatric brain sizes, to our knowledge. Finally, our data show that constitutional AKT3 mutations are associated with megalencephaly, with or without autism, similar to PTEN-related disorders. Recognition of this broad clinical and molecular spectrum of AKT3 mutations is important for providing early diagnosis and appropriate management of affected individuals, and will facilitate targeted design of future human clinical trials using PI3K-AKT pathway inhibitors.
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2. Barry CL, Epstein AJ, Marcus SC, Kennedy-Hendricks A, Candon MK, Xie M, Mandell DS. {{Effects Of State Insurance Mandates On Health Care Use And Spending For Autism Spectrum Disorder}}. {Health Aff (Millwood)}. 2017; 36(10): 1754-61.
Forty-six states and the District of Columbia have enacted insurance mandates that require commercial insurers to cover treatment for children with autism spectrum disorder (ASD). This study examined whether implementing autism mandates altered service use or spending among commercially insured children with ASD. We compared children age twenty-one or younger who were eligible for mandates to children not subject to mandates using 2008-12 claims data from three national insurers. Increases in service use and spending attributable to state mandates were detected for all outcomes. Mandates were associated with a 3.4-percentage-point increase in monthly use and a $77 increase in monthly spending on ASD-specific services. Effects were larger for younger children and increased with the number of years since mandate implementation. These increases suggest that state mandates are an effective tool for broadening access to autism treatment under commercial insurance.
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3. Cai RY, Richdale AL, Dissanayake C, Uljarevic M. {{Brief Report: Inter-Relationship between Emotion Regulation, Intolerance of Uncertainty, Anxiety, and Depression in Youth with Autism Spectrum Disorder}}. {J Autism Dev Disord}. 2017.
The aim of this study was to examine the inter-relationship between emotion regulation (ER), intolerance of uncertainty (IU), and symptoms of anxiety and depression in adolescents and young adults diagnosed with autism spectrum disorder (ASD). Sixty-one individuals aged 14-24 years (M age = 18.19; SD age = 2.19) completed the ER Questionnaire, IU Scale-12, Diagnostic and Statistical Manual of Mental Disorders-5 Dimensional Anxiety Scales, Patient Health Questionnaire-9, and Autism-Spectrum Quotient-Short. Correlation and mediation analyses were conducted. Results indicated all key variables were associated with each other and IU mediated the relationships between ER and symptoms of anxiety and of depression. Findings have implications for the design of future interventions targeting affective disorders in ASD.
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4. Chadman KK. {{Animal models for autism in 2017 and the consequential implications to drug discovery}}. {Expert Opin Drug Discov}. 2017: 1-8.
INTRODUCTION: Autism spectrum disorder (ASD) is characterized by deficits in social communication and restricted interests/repetitive behaviors, for which there are currently no approved drug treatments. The core symptoms of ASD vary widely in severity and are often accompanied by other neuropsychiatric disorders. Drug discovery has been challenging because of the lack of understanding of the underlying pathophysiology of ASD as well as the heterogeneity of symptoms and symptom severity. Areas covered: In this review, the author discusses animal models of ASD used as targets for drug discovery, focusing primarily on non-syndromic models, primarily rodents. They highlight the wide range of drug targets examined in animal models. While very little of this work has resulted in drug therapy for the behavioral symptoms of ASD yet, it has increased our knowledge of the biology of ASD that is critical for driving drug discovery and has already provided many new drug targets for investigation. Expert opinion: The information gathered from the animal models of ASD is increasing our understanding of the underlying pathophysiology for ASD and is leading to better therapeutic targets. However, the issue of small sample size, heterogeneity within clinical samples, and a lack of replicable outcome measures must be addressed to move forward.
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5. DeVilbiss EA, Magnusson C, Gardner RM, Rai D, Newschaffer CJ, Lyall K, Dalman C, Lee BK. {{Antenatal nutritional supplementation and autism spectrum disorders in the Stockholm youth cohort: population based cohort study}}. {BMJ}. 2017; 359: j4273.
Objective To determine whether nutritional supplementation during pregnancy is associated with a reduced risk of autism spectrum disorder (ASD) with and without intellectual disability in offspring.Design Observational prospective cohort study using multivariable logistic regression, sibling controls, and propensity score matching.Setting Stockholm County, Sweden.Participants 273 107 mother-child pairs identified through population registers. The study sample was restricted to children who were aged 4 to 15 years by the end of follow-up on 31 December 2011 and were born between 1996 and 2007.Exposures Multivitamin, iron, and folic acid supplement use was reported at the first antenatal visit.Main outcome measure Diagnosis of ASD with and without intellectual disability in children determined from register data up to 31 December 2011.Results Prevalence of ASD with intellectual disability was 0.26% (158 cases in 61 934) in the maternal multivitamin use group and 0.48% (430 cases in 90 480) in the no nutritional supplementation use group. Maternal multivitamin use with or without additional iron or folic acid, or both was associated with lower odds of ASD with intellectual disability in the child compared with mothers who did not use multivitamins, iron, and folic acid (odds ratio 0.69, 95% confidence interval 0.57 to 0.84). Similar estimates were found in propensity score matched (0.68, 0.54 to 0.86) and sibling control (0.77, 0.52 to 1.15) matched analyses, though the confidence interval for the latter association included 1.0 and was therefore not statistically significant. There was no consistent evidence that either iron or folic acid use were inversely associated with ASD prevalence.Conclusions Maternal multivitamin supplementation during pregnancy may be inversely associated with ASD with intellectual disability in offspring. Further scrutiny of maternal nutrition and its role in the cause of autism is recommended.
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6. Fatima S, Mottola N. {{Case 5: A 7-year-old Autistic Boy with Altered Movements and Mental Status}}. {Pediatr Rev}. 2017; 38(10): 493.
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7. Friedman C. {{A National Analysis of Medicaid Home and Community Based Services Waivers for People With Intellectual and Developmental Disabilities: FY 2015}}. {Intellect Dev Disabil}. 2017; 55(5): 281-302.
Medicaid Home and Community Based Services (HCBS) 1915(c) waivers are the largest source of funding for the long term services and supports of people with intellectual and developmental disabilities (IDD). National-level analyses of HCBS IDD waivers are crucial because of the large variance across states, the recent CMS rule and regulation changes (CMS 2249-F/2296-F), and the ever changing economic and political landscape. Therefore, the aim of this study was to examine state waiver priorities for people with IDD. In FY 2015, 111 waivers projected spending $25.6 billion for approximately 630,000 people with IDD. The services with the most funding were residential habilitation, supports to live in one’s own home, and day habilitation. However, our analysis revealed large discrepancies across states and services.
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8. Gaetz W, Jurkiewicz MT, Kessler SK, Blaskey L, Schwartz ES, Roberts TPL. {{Neuromagnetic responses to tactile stimulation of the fingers: Evidence for reduced cortical inhibition for children with Autism Spectrum Disorder and children with epilepsy}}. {Neuroimage Clin}. 2017; 16: 624-33.
The purpose of this study was to compare somatosensory responses from a group of children with epilepsy and a group of children with autism spectrum disorder (ASD), with age matched TD controls. We hypothesized that the magnitude of the tactile « P50m » somatosensory response would be reduced in both patient groups, possibly due to reduced GABAergic signaling as has been implicated in a variety of previous animal models and in vivo human MRS studies. We observed significant (~ 25%) decreases in tactile P50m dipole moment values from the source localized tactile P50m response, both for children with epilepsy and for children with ASD. In addition, the latency of the tactile P50m peak was observed to be equivalent between TD and ASD groups but was significantly delayed in children with epilepsy by ~ 6 ms. Our data support the hypothesis of impaired GABAergic signaling in both children with ASD and children with epilepsy. Further work is needed to replicate these findings and directly relate them to both in vivo measures of GABA via e.g. magnetic resonance spectroscopy and psychophysical assessments of somatosensory function, and behavioral indices.
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9. Genc-Tosun D, Kurt O. {{Teaching multi-step requesting to children with autism spectrum disorder using systematic instruction and a speech-generating device}}. {Augment Altern Commun}. 2017: 1-11.
The purpose of this study was to examine the effectiveness of an iPad-based speech-generating device (SGD) and an intervention package in teaching multi-step requesting to children with autism spectrum disorder (ASD). The intervention package comprised discrete trial teaching, time delay, graduated guidance, and reinforcement. Social validity data were also collected from parents and teachers. Three male participants with ASD, aged 4-5 years, participated in the study, which was conducted using a multiple-probe-across-participants design. Findings of the study showed that the SGD and the intervention package were effective in teaching multi-step requesting to all participants. Furthermore, the target skill was maintained and generalized to different materials and individuals. Social validity findings indicated that opinions of the mothers and teachers were positive. On the other hand, the father of one participant stated that he was concerned with possible negative effects of using tablet computers. The findings are discussed with regard to the parents’ opinions, and implications for practice and research.
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10. Gilson CB, Bethune LK, Carter EW, McMillan ED. {{Informing and Equipping Parents of People With Intellectual and Developmental Disabilities}}. {Intellect Dev Disabil}. 2017; 55(5): 347-60.
The importance of supporting families with members who have intellectual and developmental disabilities (IDD) is well-established in both policy and research. Yet little is known about how familiar parents are with existing resources (e.g., programs, supports, trainings), what information they would consider most helpful, and how they would prefer to access resources. Our study examined the resource needs of 1,738 parents of children and adults with IDD in the state of Tennessee. Most parents reported limited familiarity with programs across every domain (e.g., residential, vocational, postsecondary). The extent to which parents indicated various types of information would be helpful varied by demographic factors (e.g., daughter or son’s age, disability diagnosis, socioeconomic status), as did the avenues through which they indicated they were most likely to access information and resources. We offer recommendations aimed at equipping parents with relevant supports and resources to guide their son or daughter’s journey across the lifespan.
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11. Hampton T. {{Early Brain Imaging in Infants May Help Predict Autism}}. {JAMA}. 2017; 318(13): 1211-2.
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12. Jiraanont P, Sweha SR, AlOlaby RR, Silva M, Tang HT, Durbin-Johnson B, Schneider A, Espinal GM, Hagerman PJ, Rivera SM, Hessl D, Hagerman RJ, Chutabhakdikul N, Tassone F. {{Clinical and molecular correlates in fragile X premutation females}}. {eNeurologicalSci}. 2017; 7: 49-56.
The prevalence of the fragile X premutation (55-200 CGG repeats) among the general population is relatively high, but there remains a lack of clear understanding of the links between molecular biomarkers and clinical outcomes. In this study we investigated the correlations between molecular measures (CGG repeat size, FMR1 mRNA, FMRP expression levels, and methylation status at the promoter region and in FREE2 site) and clinical phenotypes (anxiety, obsessive compulsive symptoms, depression and executive function deficits) in 36 adult premutation female carriers and compared to 24 normal control subjects. Premutation carriers reported higher levels of obsessive compulsive symptoms, depression, and anxiety, but demonstrated no significant deficits in global cognitive functions or executive function compared to the control group. Increased age in carriers was significantly associated with increased anxiety levels. As expected, FMR1 mRNA expression was significantly correlated with CGG repeat number. However, no significant correlations were observed between molecular (including epigenetic) measures and clinical phenotypes in this sample. Our study, albeit limited by the sample size, establishes the complexity of the mechanisms that link the FMR1 locus to the clinical phenotypes commonly observed in female carriers suggesting that other factors, including environment or additional genetic changes, may have an impact on the clinical phenotypes. However, it continues to emphasize the need for assessment and treatment of psychiatric problems in female premutation carriers.
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13. Klusek J, Ruber A, Roberts JE. {{Impaired eye contact in the FMR1 premutation is not associated with social anxiety or the broad autism phenotype}}. {Clin Neuropsychol}. 2017: 1-16.
OBJECTIVE: The Fragile X Mental Retardation-1 (FMR1) premutation is a common genetic abnormality, affecting ~1:150 women in the United States. Clinical neuropsychologists are becoming increasingly aware of their role in the clinical management of the FMR1 premutation, which is associated with risk for a range of cognitive, executive, neuromotor, and psychological impairments, including neurodegenerative disease. This study investigated atypical eye contact as a critical neuropsychological phenotype associated with the FMR1 premutation. METHODS: Thirty-eight women with the FMR1 premutation and 27 control women engaged in a 20-min conversational sample with an examiner. Eye contact quality was coded from the videotaped samples by blinded coders. Mixed models tested group differences in eye contact during the beginning and the end of the conversation. Social anxiety and broad autism phenotype (BAP) traits were tested as predictors of eye contact quality across the groups. RESULTS: Women with the FMR1 premutation exhibited significantly reduced eye contact during both the beginning and the end of the social interaction, despite a ‘warm-up’ effect where eye contact improved by the end of the interaction. Eye contact quality was not associated with social anxiety or BAP traits. CONCLUSIONS: This study supports reduced eye contact as a phenotypic feature of the FMR1 premutation, which presents independent of social anxiety and the BAP. These findings contribute to a growing understanding of the neuropsychological phenotype of the FMR1 premutation, which has public health implications given that >1 million individuals in the United States carry this genetic abnormality.
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14. Lugo Marin J, Alviani Rodriguez-Franco M, Mahtani Chugani V, Magan Maganto M, Diez Villoria E, Canal Bedia R. {{Prevalence of Schizophrenia Spectrum Disorders in Average-IQ Adults with Autism Spectrum Disorders: A Meta-analysis}}. {J Autism Dev Disord}. 2017.
Since their separation as independent diagnostics, autism spectrum disorders (ASD) and schizophrenia spectrum disorders (SSD) have been conceptualized as mutually exclusive disorders. Similarities between both disorders can lead to misdiagnosis, especially when it comes to average-IQ adults who were not identified during childhood. The aim of this review was to examine the occurrence of SSD in average-IQ adults with ASD. Electronic and manual searches identified a total of 278 references, of which 10 were included in a meta-analysis. The pooled prevalence of SSD in the total ASD sample was close to 6%, pointing to a high co-occurrence of the two conditions. Further research is needed to determine the factors that predispose members of this population to the emergence of psychotic disorders.
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15. Magyar CI, Pandolfi V. {{Utility of the CBCL DSM-Oriented Scales in Assessing Emotional Disorders in Youth with Autism}}. {Res Autism Spectr Disord}. 2017; 37: 11-20.
BACKGROUND: Youth with autism spectrum disorder (ASD) are at risk for one or more emotional disorders (ED) including depressive and anxiety conditions. DSM-5 diagnostic guidelines indicate that co-occurring ED must be specified when present (APA, 2013). While ED may be evaluated for during initial diagnostic assessment, routine monitoring and screening is needed to identify emerging ED in later childhood and adolescence, a period of high risk. METHOD: Confirmatory factor analysis, convergent and divergent validity analyses, criterion-related validity, and diagnostic accuracy analyses of the CBCL’s Affective Problems and Anxiety Problems DSM Oriented Scales was completed on 93 well-characterized youth, ages 6 to 18 years with ASD (6:1 M:F), with and without intellectual impairment. These youth were from predominately white, middle-class backgrounds. RESULTS: Each scale measured a single construct reliably (depressive and anxiety disorders), neither scale measured symptoms of ASD, and youth with a depressive disorder had other ED co-morbidities. CONCLUSIONS: Findings demonstrate the DSM Oriented Affective and Anxiety Problem Scales can be used to screen for depression and anxiety in youth with ASD. Replication is needed with various subgroups representing gender, age, developmental level, autism, and mental health severity differences, and with groups across a broader set of demographics.
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16. Nakanishi M, Nomura J, Ji X, Tamada K, Arai T, Takahashi E, Bucan M, Takumi T. {{Correction: Functional significance of rare neuroligin 1 variants found in autism}}. {PLoS Genet}. 2017; 13(10): e1007035.
[This corrects the article DOI: 10.1371/journal.pgen.1006940.].
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17. Nijhof AD, Brass M, Wiersema JR. {{Spontaneous mentalizing in neurotypicals scoring high versus low on symptomatology of autism spectrum disorder}}. {Psychiatry Res}. 2017; 258: 15-20.
Spontaneous mentalizing ability has been linked to symptoms severity in individuals with autism spectrum disorder (ASD). Here we investigated whether in neurotypicals, higher levels of ASD symptomatology could also be linked to lower levels of spontaneous mentalizing, by comparing neurotypicals scoring high with those scoring low on the short Autism Spectrum Quotient. Participants watched movies during which they, and another agent, formed beliefs about the location of an object. These beliefs could influence reaction times (RT) to that object in the outcome phase. We expected participants with more ASD symptoms to show less spontaneous mentalizing, as reflected by a smaller effect of the other agent’s beliefs on RT patterns (the ToM index). In contrast, the effect of own beliefs on RTs, reflecting an egocentric bias, was expected to be larger in the high-scoring group. Results showed that groups differed in the effect of the agent’s beliefs; the ToM index was highly significant in the low-scoring group, while being absent in the high-scoring group. No difference in egocentric bias was observed. These findings suggest that the relationship between levels of ASD symptomatology and spontaneous mentalizing is not only present in individuals with ASD, but also in the neurotypical population.
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18. Palmer N, Beam A, Agniel D, Eran A, Manrai A, Spettell C, Steinberg G, Mandl K, Fox K, Nelson SF, Kohane I. {{Association of Sex With Recurrence of Autism Spectrum Disorder Among Siblings}}. {JAMA Pediatr}. 2017.
Importance: Autism spectrum disorder (ASD) is known to be more prevalent among males than females in the general population. Although overall risk of recurrence of ASD among siblings has been estimated to be between 6.1% and 24.7%, information on sex-specific recurrence patterns is lacking. Objective: To estimate high-confidence sex-specific recurrence rates of ASD among siblings. Design, Setting, and Participants: This observational study used an administrative database to measure the incidence of ASD among children in 1583271 families (37507 with at least 1 diagnosis of ASD) enrolled in commercial health care insurance plans at a large US managed health care company from January 1, 2008, through February 29, 2016. Families in the study had 2 children who were observed for at least 12 months between 4 and 18 years of age. Main Outcomes and Measures: The primary measure of ASD recurrence was defined as the diagnosis of ASD in a younger sibling of an older sibling with an ASD diagnosis. Results: Among the 3166542 children (1547266 females and 1619174 males; mean [SD] age, 11.2 [4.7] years) in the study, the prevalence of ASD was 1.96% (95% CI, 1.94%-1.98%) among males and 0.50% (95% CI, 0.49%-0.51%) among females. When a male was associated with risk in the family, ASD was diagnosed in 4.2% (95% CI, 3.8%-4.7%) of female siblings and 12.9% (95% CI, 12.2%-13.6%) of male siblings. When a female was associated with risk in the family, ASD was diagnosed in 7.6% (95% CI, 6.5%-8.9%) of female siblings and 16.7% (95% CI, 15.2%-18.4%) of male siblings. Conclusions and Relevance: These findings are in agreement with the higher rates of ASD observed among males than among females in the general population. Our study provides more specific guidance for the screening and counseling of families and may help inform future investigations into the environmental and genetic factors that confer risk of ASD.
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19. Ryan S, Fraser-Thomas J, Weiss JA. {{Patterns of sport participation for youth with autism spectrum disorder and intellectual disability}}. {J Appl Res Intellect Disabil}. 2017.
BACKGROUND: Little is known about sport participation in youth with Autism Spectrum Disorder (ASD). The current study examined sport characteristics (frequency, diversity, positive social experiences [PSE]) for youth with ASD and intellectual disability compared to youth with intellectual disability alone and explored the personal and contextual correlates of involvement. METHOD: Parents (N = 409) completed an online survey, and multiple mediation analyses were used to examine the factors that explained the relationships between sport involvement in youth with ASD and intellectual disability. RESULTS: No significant main effects of ASD status were found for frequency or diversity, but youth with intellectual disability alone had higher scores for PSE compared to youth with ASD and intellectual disability. Sociocommunicative abilities, coach relationship and resources mediated the relationship between ASD status and PSE. CONCLUSIONS: A better understanding of the factors related to sport is essential for allowing families, service providers and policy makers to improve involvement for youth with ASD.
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20. Sandin S, Lichtenstein P, Kuja-Halkola R, Hultman C, Larsson H, Reichenberg A. {{The Heritability of Autism Spectrum Disorder}}. {JAMA}. 2017; 318(12): 1182-4.
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21. Sheikh TI, Martinez de Paz A, Akhtar S, Ausio J, Vincent JB. {{MeCP2 isoform N-terminal modifications affect its degradation rate and are disrupted by the Ala2Val Rett mutation}}. {Hum Mol Genet}. 2017.
Methyl CpG-binding protein 2 (MeCP2), the mutated protein in Rett syndrome (RTT), is a crucial chromatin-modifying and gene-regulatory protein that has two main isoforms (MeCP2_E1 and MeCP2_ E2) due to the alternative splicing and switching between translation start codons in exons one and two. Functionally, these two isoforms appear to be virtually identical; however, evidence suggests that only MeCP2_E1 is relevant to RTT, including a single RTT missense mutation in exon 1, Ala2Val. Here, we show that N-terminal co- and post-translational modifications differ for MeCP2_E1 and MeCP2_E1-Ala2Val, which result in different protein degradation rates in vitro. We report complete N-methionine excision (NME) for MeCP2_E1 and evidence of excision of multiple alanine residues from the N-terminal polyalanine stretch. For MeCP2_E1-Ala2Val, we observed only partial NME and N-acetylation (NA) of either methionine or valine. The localization of MeCP2_E1 and co-localization with chromatin appear to be unaffected by the Ala2Val mutation. However, a higher proteasomal degradation rate was observed for MeCP2_E1-Ala2Val compared with that for wild type (WT) MeCP2_E1. Thus, the etiopathology of Ala2Val is likely due to a reduced bio-availability of MeCP2 because of the faster degradation rate of the unmodified defective protein. Our data on the effects of the Ala2Val mutation on N-terminal modifications of MeCP2 may be applicable to Ala2Val mutations in other disease genes for which for no etiopathological mechanism has been established.
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22. Stahlhut M, Downs J, Aadahl M, Leonard H, Bisgaard AM, Nordmark E. {{Patterns of sedentary time and ambulatory physical activity in a Danish population of girls and women with Rett syndrome}}. {Disabil Rehabil}. 2017: 1-9.
BACKGROUND: Rett syndrome (RTT) is a rare neurodevelopmental disorder leading to multiple disabilities and high dependency on caregivers. This study aimed to: (1) describe the patterns of sedentary time and daily steps and (2) identify the association of individual and environmental characteristics with sedentary time. METHODS: All Danish females with RTT older than 5 years of age and with a MECP2 mutation were invited to participate. The activPAL and StepWatch Activity Monitor (SAM) were worn by participants for at least four days. Sedentary time and step counts were plotted by time to examine daily activity patterns. Associations between sedentary time and individual and environmental covariates were assessed with linear regression models. RESULTS: The median (interquartile range) age of participants was 22.0 (14.3-36.5) years. On average 83.3% (standard deviation 13.9%) of waking hours were spent in sedentary behaviours (n = 48) and the median (interquartile range) daily step count was 5128 (2829-7704) (n = 28). Females older than 33.5 years, and those unable to walk independently were more sedentary. CONCLUSIONS: This study demonstrated high levels of sedentary time and low daily step counts in a Danish population of females with RTT. Advancing age and lower walking skills were associated with higher levels of sedentary time. Implications for Rehabilitation Sedentary lifestyles in individuals with disabilities have a negative impact on health and quality of life. High levels of sedentary time and low daily step counts were demonstrated in a Danish population of females with Rett syndrome. Advancing age and inability to walk independently were strongly associated with higher levels of sedentary time in females with Rett syndrome. Understanding patterns of sedentary behaviour and physical activity can aid health care professionals in developing health-promoting physical activity interventions.
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23. Szatmari P. {{Risk and resilience in autism spectrum disorder: a missed translational opportunity?}}. {Dev Med Child Neurol}. 2017.
The objective of this review is to provide a narrative summary of risk and resiliency in autism spectrum disorder (ASD) over the lifespan. In recent years, much has been learned about risk factors for ASD which include both genetic and environmental mechanisms. Resiliency in ASD is much less studied but examples can be gleaned by exploring studies that allow for heterogeneity in causation and outcome. Possible examples come from the literature on sex difference, infant siblings, and natural history. Exciting translational opportunities can be achieved through a greater focus on understanding protective factors and resiliency in ASD than the field’s almost exclusive focus on risk factors and the ability to predict poor outcomes. Although the exact nature of processes that protect in ASD are not yet known, putting a resiliency lens on research and clinical practice may prove illuminating.
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24. Turi M, Muratori F, Tinelli F, Morrone MC, Burr DC. {{Autism is associated with reduced ability to interpret grasping actions of others}}. {Sci Rep}. 2017; 7(1): 12687.
We investigated the ability of children with ASD to discriminate a small cylinder from a large cube by observing a point-light movie of an actor grasping the object, either from an allocentric or egocentric viewpoint (observing action of others or self). Compared with typically developing controls, high functioning autistic children showed a strong selective impairment in this task, but only with the allocentric viewpoint, where thresholds were twice as high: egocentric thresholds were similar to age- and ability-matched controls. The magnitude of the impairment correlated strongly with the degree of symptomology (R2 = 0.5). The results suggest that children with ASD might be impaired in their ability to predict and infer the consequences of others’ movements, which could be related to the social-communicative deficits often reported in autism.
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25. Westerveld MF, Roberts JMA. {{The Oral Narrative Comprehension and Production Abilities of Verbal Preschoolers on the Autism Spectrum}}. {Lang Speech Hear Serv Sch}. 2017; 48(4): 260-72.
Purpose: This study described the oral narrative comprehension and production skills of verbal preschool-age children on the autism spectrum and investigated correlations between oral narrative ability and norm-referenced language test performance. Method: Twenty-nine preschool-age children (aged 4;0-5;9 years;months) with autism, who obtained an age-equivalent score of at least 36 months on the expressive communication subscale of the Vineland Adaptive Behavior Scales-Second Edition (Sparrow, Cicchetti, & Balla, 2005), participated. Children listened to an unfamiliar fictional narrative and answered comprehension questions afterward. After listening to the narrative a second time, children were asked to retell the narrative without picture support. Narratives were transcribed and analyzed for length, semantic diversity, grammatical complexity and accuracy, intelligibility, inclusion of critical events, and narrative stage. Results: All children participated in the comprehension task, and 19 children produced an analyzable narrative retell. Compared with published data on typically developing children, significant difficulties were observed in narrative comprehension, intelligibility, and grammatical accuracy. Most of the children told descriptive or action sequences, with only 1 child producing an abbreviated episode. Significant positive correlations were found (a) between performance on the Peabody Picture Vocabulary Test-Fourth Edition (Dunn & Dunn, 2007) and semantic diversity and narrative comprehension and (b) between parent-reported receptive communication competence (Vineland Adaptive Behavior Scales-Second Edition) and narrative comprehension. Conclusions: This study provides preliminary evidence of specific difficulties in oral narrative comprehension and production skills in verbal preschoolers on the autism spectrum.
