1. {{Assistance with treatment choices related to autism}}. {Nurse Educ};2012 (Mar);37(2):49.
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2. Al Keilani MA, Carlier S, Groswasser J, Dan B, Deconinck N. {{Rett syndrome associated with continuous spikes and waves during sleep}}. {Acta Neurol Belg};2011 (Dec);111(4):328-332.
Major speech impairment is a cardinal feature of Rett syndrome. Epilepsy, of variable presentation, is also frequently described. We report a girl who presented rapid speech regression while EEG showed continuous spikes and waves during slow sleep. The clinical picture was consistent with Rett syndrome, confirmed by MECP2 mutation R133C. We hypothesized that speech regression was partially related to nocturnal epileptic activity. Several antiepileptic drugs were used unsuccessfully but valproic acid was accompanied by improvement of verbal fluency, social interaction and manual abilities as measured by the Quebec Scale of Adaptive Behaviors and the Rett syndrome adapted Kerr scale. Continuous spikes and waves during slow sleep are unexpected in the early stages of Rett syndrome. This report suggests that it might contribute to the clinical impairment, in particular communicative capabilities, and that adequate antiepileptic treatment may be beneficial.
3. Aldred C, Green J, Emsley R, McConachie H. {{Brief report: mediation of treatment effect in a communication intervention for pre-school children with autism}}. {J Autism Dev Disord};2012 (Mar);42(3):447-454.
Tests of mediation in treatment trials can illuminate processes of change and suggest causal influences in development. We conducted a mediation analysis of a previously published randomised controlled trial of parent-mediated communication-focused treatment for autism against ordinary care, with 28 children aged 2-5 years (Aldred et al. in J Child Psychol Psychiatr 45:1-11, 2004). The hypothesised mediating process, targeted by the intervention, was an increase in parental synchronous response within parent-child interaction. The results showed partial mediation, with change in synchrony accounting for 34% of the positive intervention effect on autism symptomatology (Autism Diagnostic Observation Schedule communication and social domain algorithm); the result was confirmed by bootstrap estimation. Improved parental synchronous response to child communication can alter short-term autism symptom outcome with targeted therapy.
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4. Annaz D, Campbell R, Coleman M, Milne E, Swettenham J. {{Young children with autism spectrum disorder do not preferentially attend to biological motion}}. {J Autism Dev Disord};2012 (Mar);42(3):401-408.
Preferential attention to biological motion can be seen in typically developing infants in the first few days of life and is thought to be an important precursor in the development of social communication. We examined whether children with autism spectrum disorder (ASD) aged 3-7 years preferentially attend to point-light displays depicting biological motion. We found that children with ASD did not preferentially attend to biological motion over phase-scrambled motion, but did preferentially attend to a point-light display of a spinning top rather than a human walker. In contrast a neurotypical matched control group preferentially attended to the human, biological motion in both conditions. The results suggest a core deficit in attending to biological motion in ASD.
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5. Benson V, Castelhano MS, Au-Yeung SK, Rayner K. {{Eye movements reveal no immediate « WOW » (« which one’s weird ») effect in autism spectrum disorder}}. {Q J Exp Psychol (Hove)};2011 (Nov 30)
Autism spectrum disorder (ASD) and typically developed (TD) adult participants viewed pairs of scenes for a simple « spot the difference » (STD) and a complex « which one’s weird » (WOW) task. There were no group differences in the STD task. In the WOW task, the ASD group took longer to respond manually and to begin fixating the target « weird » region. Additionally, as indexed by the first-fixation duration into the target region, the ASD group failed to « pick up » immediately on what was « weird ». The findings are discussed with reference to the complex information processing theory of ASD (Minshew & Goldstein, 1998 ).
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6. Bevan Jones R, Thapar A, Lewis G, Zammit S. {{The association between early autistic traits and psychotic experiences in adolescence}}. {Schizophr Res};2012 (Mar);135(1-3):164-169.
BACKGROUND: There has been growing interest in the clinical and biological links between autistic spectrum disorder and psychotic disorders, and between symptoms of these disorders that exist below diagnostic thresholds. Whilst autism and schizophrenia are regarded as distinct disorders, recent studies support an overlap in the genetic architecture across these conditions. Although early neurodevelopmental impairment is associated with psychotic disorders in later life, evidence from longitudinal studies of the relationship between autistic traits and psychotic experiences is limited. Aims The aim of the study is to explore whether children with early autistic traits (social interaction and communication problems, and restricted, repetitive interests and behaviours) are more likely to present with psychotic experiences in early adolescence. METHOD: Longitudinal study using the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. The mothers of 8232 children were asked about autistic traits in their children as part of the Development and Well-Being Assessment (DAWBA) at the age of 7. Of those, 6439 children completed a semi-structured clinical assessment for psychotic experiences at the age of 12. RESULTS: Children whose mothers had concerns about autistic traits in early life, in particular with regard to speech development or ‘rituals’/’habits’, were more likely to develop psychotic experiences in early adolescence. The greater the number of early autistic traits a child had, the greater their risk of developing psychotic experiences. These associations were not confounded by IQ, family history of depression or schizophrenia, gender or socio-demographic characteristics. CONCLUSIONS: Childhood autistic traits, and particularly speech problems and odd rituals or unusual habits, are associated with psychotic experiences in adolescence. This may be a result of a shared aetiology or because autistic traits may also be an early precursor of psychotic experiences.
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7. Bishop SL, Seltzer MM. {{Self-Reported Autism Symptoms in Adults with Autism Spectrum Disorders}}. {J Autism Dev Disord};2012 (Feb 24)
Scores on the autism spectrum quotient (AQ) were examined in 65 adults with ASD. Maternal reports of symptoms were collected simultaneously using the autism diagnostic interview-revised (ADI-R) and the Vineland Screener. A slightly revised AQ administration procedure was used to accommodate adults with below average IQ. AQ scores were lower than in the original validation study, with only 11 adults (17%) scoring above the proposed diagnostic cut-off and 24 (27%) exceeding the screening cut-off. Adults with higher IQs endorsed more symptoms than those with below average intelligence, but even when analyses were restricted to the 39 adults with at least average IQ, only 44% met the screening cut-off. AQ scores were not significantly correlated with ADI-R or Vineland scores.
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8. Boison D. {{Is Intrinsic Hyperexcitability in CA3 the Culprit for Seizures in Rett Syndrome?}}. {Epilepsy Curr};2012 (Jan);12(1):13-14.
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9. Bolton PF, Golding J, Emond A, Steer CD. {{Autism spectrum disorder and autistic traits in the avon longitudinal study of parents and children: precursors and early signs}}. {J Am Acad Child Adolesc Psychiatry};2012 (Mar);51(3):249-260 e225.
OBJECTIVE: To chart the emergence of precursors and early signs of autism spectrum disorder (ASD) and autistic traits in the Avon Longitudinal Study of Parents and Children, a prospective longitudinal cohort study of the surviving offspring of 14,541 pregnant women from southwestern England with an expected delivery date between April 1991 and December 1992. METHOD: Parents’ contemporaneous reports of their infant’s development (241 questionnaire responses collected up to 30 months of age) were examined in relation to the diagnosis of autism spectrum disorder by age 11 years (n = 86) and a measure of autistic traits, derived by factor analysis. RESULTS: Among the children later diagnosed with ASD, concerns about vision and hearing were more often reported in the first year, and differences in social, communication, and fine motor skills were evident from 6 months of age. Repetitive behaviors and differences in play, imitation, and feeding habits were reported in the second year. Differences in temperament emerged at 24 months of age and bowel habit by 30 months. All of these early signs were strongly associated with the presence of autistic traits in the rest of the population and these differences were often evident in the first year of development. Over the first 30 months of development, the best predictors of both later ASD and autistic traits included the Social Achievement and Communication scores from the Denver Developmental Screening Test, measures of communicative skills (Vocabulary and Combines Words) from the MacArthur Infant Communicative Development Inventories, and a repetitive behavior score. CONCLUSIONS: Precursors, early signs, and other developmental differences were reported in the first year of development among children from the general population who later developed autism spectrum disorder and subtler autistic traits. Other differences emerged and unfolded as development progressed. The findings confirm the long-held suspicion that early differences underscore the multifaceted nature of autism spectrum disorder and the broader autism phenotype, and highlight the centrality of impairments in social communication skills.
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10. Boucher J. {{Research Review: Structural language in autistic spectrum disorder – characteristics and causes}}. {J Child Psychol Psychiatry};2012 (Mar);53(3):219-233.
Background: Structural language anomalies or impairments in autistic spectrum disorder (ASD) are theoretically and practically important, although underrecognised as such. This review aims to highlight the ubiquitousness of structural language anomalies and impairments in ASD, and to stimulate investigation of their immediate causes and implications for intervention. Method: Studies of structural language in ASD are reviewed (based on a search of the literature and selected as meeting defined inclusion criteria), and explanatory hypotheses are discussed. Results: Some individuals with ASD never acquire language. Amongst those who do, language abilities range from clinically normal (ALN) to various degrees of impairment (ALI). Developmental trajectories and individual profiles are diverse, and minority subgroups have been identified. Specifically: language is commonly but not always delayed and delayed early language is always characterised by impaired comprehension and odd utterances, and sometimes by deviant articulation and grammar. Nevertheless, by school age an ‘ASD-typical’ language profile emerges from group studies, with articulation and syntax least affected, and comprehension, semantics and certain facets of morphology most affected. Thus, even individuals with ALN have poor comprehension relative to expressive language; also semantic-processing anomalies and idiosyncratic word usage. It is argued that impaired socio-emotional-communicative relating, atypical sensory-perceptual processing, and uneven memory/learning abilities may underlie shared language anomalies across the spectrum; and that varying combinations of low nonverbal intelligence, semantic memory impairment and comorbidities including specific language impairment (SLI), hearing impairment, and certain medical syndromes underlie ALI and variation in individual profiles. Conclusions: Structural language is universally affected in ASD, due to a complex of shared and unshared causal factors. There is an urgent need for more research especially into the characteristics and causes of clinically significant language impairments.
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11. Brock ME, Freuler A, Baranek GT, Watson LR, Poe MD, Sabatino A. {{Temperament and Sensory Features of Children with Autism}}. {J Autism Dev Disord};2012 (Feb 25)
This study sought to characterize temperament traits in a sample of children with autism spectrum disorder (ASD), ages 3-7 years old, and to determine the potential association between temperament and sensory features in ASD. Individual differences in sensory processing may form the basis for aspects of temperament and personality, and aberrations in sensory processing may inform why some temperamental traits are characteristic of specific clinical populations. Nine dimensions of temperament from the Behavioral Style Questionnaire (McDevitt and Carey in Manual for the behavioral style questionnaire, Behavioral-Developmental Initiatives, Scottsdale, AZ, 1996) were compared among groups of children with ASD (n = 54), developmentally delayed (DD; n = 33), and the original normative sample of typically developing children (McDevitt and Carey in J Child Psychol Psychiatr 19(3):245-253, 1978; n = 350) using an ANOVA to determine the extent to which groups differed in their temperament profiles. The hypothesized overlap between three sensory constructs (hyperresponsiveness, hyporesponsivness, and seeking) and the nine dimensions of temperament was analyzed in children with ASD using regression analyses. The ASD group displayed temperament scores distinct from norms for typically developing children on most dimensions of temperament (activity, rhythmicity, adaptability, approach, distractibility, intensity, persistence, and threshold) but differed from the DD group on only two dimensions (approach and distractibility). Analyses of associations between sensory constructs and temperament dimensions found that sensory hyporesponsiveness was associated with slowness to adapt, low reactivity, and low distractibility; a combination of increased sensory features (across all three patterns) was associated with increased withdrawal and more negative mood. Although most dimensions of temperament distinguished children with ASD as a group, not all dimensions appear equally associated with sensory response patterns. Shared mechanisms underlying sensory responsiveness, temperament, and social withdrawal may be fruitful to explore in future studies.
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12. Brugha TS, McManus S, Smith J, Scott FJ, Meltzer H, Purdon S, Berney T, Tantam D, Robinson J, Radley J, Bankart J. {{Validating two survey methods for identifying cases of autism spectrum disorder among adults in the community}}. {Psychol Med};2012 (Mar);42(3):647-656.
BACKGROUND: There are no tested methods for conducting epidemiological studies of autism spectrum disorders (ASDs) in adult general population samples. We tested the validity of the Autism Diagnostic Observation Schedule module-4 (ADOS-4) and the 20-item Autism-Spectrum Quotient (AQ-20). METHOD: Randomly sampled adults aged >/=16 years were interviewed throughout England in a general population multi-phase survey. The AQ-20 was self-completed by 7353 adults in phase 1. A random subset completed phase 2, ADOS-4 assessments (n=618); the probability of selection increased with AQ-20 score. In phase 3, informant-based Diagnostic Interview Schedule for Social and Communication Disorders (DISCO) and Autism Diagnostic Interview-Revised (ADI-R) developmental assessments were completed (n=56). Phase 1 and 2 data were presented as vignettes to six experienced clinicians (working in pairs). The probability of respondents having an ASD was compared across the three survey phases. RESULTS: There was moderate agreement between clinical consensus diagnoses and ADOS-4. A range of ADOS-4 caseness thresholds was identified by clinicians: 5+ to 13+ with greatest area under the curve (AUC) at 5+ (0.88). Modelling of the presence of ASD using 56 DISCO assessments suggested an ADOS-4 threshold in the range of 10+ to 13+ with the highest AUC at ADOS 10+ to 11+ (0.93-0.94). At ADOS 10+, the sensitivity was 1 [95% confidence interval (CI) 0.59-1.0] and the specificity 0.86 (95% CI 0.72-0.94). The AQ-20 was only a weak predictor of ADOS-4 cases. CONCLUSIONS: Clinically recommended ADOS-4 thresholds are also recommended for community cases: 7+ for subthreshold and 10+ for definite cases. Further work on adult population screening methods is needed.
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13. Constantino JN, Todorov A, Hilton C, Law P, Zhang Y, Molloy E, Fitzgerald R, Geschwind D. {{Autism recurrence in half siblings: strong support for genetic mechanisms of transmission in ASD}}. {Mol Psychiatry};2012 (Feb 28)
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14. Davis TE, 3rd, Moree BN, Dempsey T, Hess JA, Jenkins WS, Fodstad JC, Matson JL. {{The effect of communication deficits on anxiety symptoms in infants and toddlers with autism spectrum disorders}}. {Behav Ther};2012 (Mar);43(1):142-152.
Autism spectrum disorders (ASDs) are life-long developmental disorders characterized by impairments in the development of reciprocal social and communication skills, abnormal language development, and a restricted repertoire of behaviors and interests. While it has been known for some time that children with ASD can evince elevated rates of anxiety symptoms, little research has been conducted on whether deficits in communication skills affect the range of anxiety symptoms in infants and toddlers with ASD. This study represents a first attempt to determine whether deficits in communication skills have an effect on the expression of anxiety in infants and toddlers with autistic disorder and pervasive developmental disorder-not otherwise specified. Seven hundred thirty-five infants were evaluated with respect to the nature and extent of anxiety symptoms and developmental functioning. Both receptive and expressive communication skills appeared to play a significant role in the manifestation of anxiety symptoms.
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15. de Bruin EI, Verheij F. {{Social skills training in children with PDD-NOS: An exploratory study}}. {Int J Psychiatry Clin Pract};2012 (Mar);16(1):60-67.
Abstract Objective. A deficit in social interaction is characteristic for children with Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS). The aim of this exploratory study is to assess the effect of Social Skills Training (SST) in children with DSM-IV based PDD-NOS. Methods. Ten consecutively referred children (n = 3 girls and n = 7 boys, mean age = 8.5, mean Full Scale Intelligence Quotient [FSIQ] = 104) participated in the standardized SST in a university outpatient department of child psychiatry. The valid and reliable Children’s Social Behaviour Questionnaire (CSBQ) and Self-Perception Profile for Children (SPPC) were filled out pre- and post treatment by parents and children respectively. Results. Parent’s CSBQ total and subscale « Social understanding » scores were significantly lower after the SST. Children’s scores on the subscale « Scholastic Competence » of the SPPC were significantly higher after SST, whereas their scores on the SPPC subscale « Physical Appearance » were significantly lower after SST as compared to before. Conclusions. This study provides a first indication of positive effects of SST in children with PDD-NOS.
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16. De Palma G, Catalani S, Franco A, Brighenti M, Apostoli P. {{Lack of Correlation Between Metallic Elements Analyzed in Hair by ICP-MS and Autism}}. {J Autism Dev Disord};2012 (Mar);42(3):342-353.
A cross-sectional case-control study was carried out to evaluate the concentrations of metallic elements in the hair of 44 children with diagnosis of autism and 61 age-balanced controls. Unadjusted comparisons showed higher concentrations of molybdenum, lithium and selenium in autistic children. Logistic regression analysis confirmed the role of risk factor for male gender and showed a slight association with molybdenum concentrations. Unconventional chelation and vitamin-mineral supplementation were ineffective on elemental hair concentrations. A meta-analysis including the present and previous similar studies excluded any association of autism with hair concentrations of mercury, cadmium, selenium, lithium and copper. A slight association was found for lead only, but it was very weak, as strictly dependent on the worst data from one study.
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17. Egawa J, Watanabe Y, Nunokawa A, Endo T, Kaneko N, Tamura R, Sugiyama T, Someya T. {{A detailed association analysis between the tryptophan hydroxylase 2 (TPH2) gene and autism spectrum disorders in a Japanese population}}. {Psychiatry Res};2012 (Feb 21)
We conducted a detailed association analysis between the tryptophan hydroxylase 2 gene and autism spectrum disorders in a Japanese population using 19 markers, including tagging single nucleotide polymorphisms and a novel missense variation, p.R225Q, identified through exon resequencing. However, we failed to obtain supportive evidence for an association.
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18. Emerson E. {{Deprivation, ethnicity and the prevalence of intellectual and developmental disabilities}}. {J Epidemiol Community Health};2012 (Mar);66(3):218-224.
Background Social gradients and ethnic disparities have been reported in some forms of intellectual and developmental disabilities. However, information on the association between area deprivation, ethnicity and other forms of intellectual and developmental disabilities are inconclusive. Aim To estimate the independent association between household disadvantage, local area deprivation, ethnicity and the identification of intellectual and developmental disability. Methods Cross-sectional survey involving multilevel multivariate analyses of data extracted from educational records on household disadvantage, local area deprivation, ethnicity and identified intellectual and developmental disability in a sample of English children aged 7-15 years (n=5.18 million). Results Lower household socio-economic position was associated with increased rates of identification of intellectual and developmental disabilities especially less severe forms of intellectual disability. Higher area deprivation was independently associated with increased rates of identification of less severe forms of intellectual disability but decreased rates of identification of profound multiple intellectual disability and autism spectrum disorder. Minority ethnic status was, in general, associated with lower rates of identification of intellectual and developmental disabilities. Exceptions to this general pattern included higher rates of identification of less severe forms of intellectual disability among Gypsy/Romany and Traveller children of Irish heritage, and higher rates of identification of more severe forms of intellectual disability among children of Pakistani and Bangladeshi heritage. Conclusions Children whose development is already compromised (and especially children with less severe intellectual disabilities) are at increased risk of exposure to social conditions that are themselves inimical to healthy development.
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19. Enticott PG, Kennedy HA, Rinehart NJ, Tonge BJ, Bradshaw JL, Taffe JR, Daskalakis ZJ, Fitzgerald PB. {{Mirror Neuron Activity Associated with Social Impairments but not Age in Autism Spectrum Disorder}}. {Biol Psychiatry};2012 (Mar 1);71(5):427-433.
BACKGROUND: The neurobiology of autism spectrum disorder (ASD) is not particularly well understood, and biomedical treatment approaches are therefore extremely limited. A prominent explanatory model suggests that social-relating symptoms may arise from dysfunction within the mirror neuron system, while a recent neuroimaging study suggests that these impairments in ASD might reduce with age. METHODS: Participants with autism spectrum disorder (i.e., DSM-IV autistic disorder or Asperger’s disorder) (n = 34) and matched control subjects (n = 36) completed a transcranial magnetic stimulation study in which corticospinal excitability was assessed during the observation of hand gestures. RESULTS: Regression analyses revealed that the ASD group presented with significantly reduced corticospinal excitability during the observation of a transitive hand gesture (relative to observation of a static hand) (p < .05), which indicates reduced putative mirror neuron system activity within ventral premotor cortex/inferior frontal gyrus. Among the ASD group, there was also a negative association between putative mirror neuron activity and self-reported social-relating impairments, but there was no indication that mirror neuron impairments in ASD decrease with age. CONCLUSIONS: These data provide general support for the mirror neuron hypothesis of autism; researchers now must clarify the precise functional significance of mirror neurons to truly understand their role in the neuropathophysiology of ASD and to determine whether they should be used as targets for the treatment of ASD.
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20. Eyler LT, Pierce K, Courchesne E. {{A failure of left temporal cortex to specialize for language is an early emerging and fundamental property of autism}}. {Brain};2012 (Mar);135(Pt 3):949-960.
Failure to develop normal language comprehension is an early warning sign of autism, but the neural mechanisms underlying this signature deficit are unknown. This is because of an almost complete absence of functional studies of the autistic brain during early development. Using functional magnetic resonance imaging, we previously observed a trend for abnormally lateralized temporal responses to language (i.e. greater activation on the right, rather than the expected left) in a small sample (n = 12) of sleeping 2-3 year olds with autism in contrast to typically developing children, a finding also reported in autistic adults and adolescents. It was unclear, however, if findings of atypical laterality would be observed in a larger sample, and at even earlier ages in autism, such as around the first birthday. Answers to these questions would provide the foundation for understanding how neurofunctional defects of autism unfold, and provide a foundation for studies using patterns of brain activation as a functional early biomarker of autism. To begin to examine these issues, a prospective, cross-sectional design was used in which brain activity was measured in a large sample of toddlers (n = 80) during the presentation of a bedtime story during natural sleep. Forty toddlers with autism spectrum disorder and 40 typically developing toddlers ranging in age between 12-48 months participated. Any toddler with autism who participated in the imaging experiment prior to final diagnosis was tracked and diagnoses confirmed at a later age. Results indicated that at-risk toddlers later diagnosed as autistic display deficient left hemisphere response to speech sounds and have abnormally right-lateralized temporal cortex response to language; this defect worsens with age, becoming most severe in autistic 3- and 4-year-olds. Typically developing children show opposite developmental trends with a tendency towards greater temporal cortex response with increasing age and maintenance of left-lateralized activation with age. We have now demonstrated lateralized abnormalities of temporal cortex processing of language in autism across two separate samples, including a large sample of young infants who later are diagnosed with autism, suggesting that this pattern may reflect a fundamental early neural developmental pathology in autism.
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21. Fatemi SH, Aldinger KA, Ashwood P, Bauman ML, Blaha CD, Blatt GJ, Chauhan A, Chauhan V, Dager SR, Dickson PE, Estes AM, Goldowitz D, Heck DH, Kemper TL, King BH, Martin LA, Millen KJ, Mittleman G, Mosconi MW, Persico AM, Sweeney JA, Webb SJ, Welsh JP. {{Consensus Paper: Pathological Role of the Cerebellum in Autism}}. {Cerebellum};2012 (Feb 28)
There has been significant advancement in various aspects of scientific knowledge concerning the role of cerebellum in the etiopathogenesis of autism. In the current consensus paper, we will observe the diversity of opinions regarding the involvement of this important site in the pathology of autism. Recent emergent findings in literature related to cerebellar involvement in autism are discussed, including: cerebellar pathology, cerebellar imaging and symptom expression in autism, cerebellar genetics, cerebellar immune function, oxidative stress and mitochondrial dysfunction, GABAergic and glutamatergic systems, cholinergic, dopaminergic, serotonergic, and oxytocin-related changes in autism, motor control and cognitive deficits, cerebellar coordination of movements and cognition, gene-environment interactions, therapeutics in autism, and relevant animal models of autism. Points of consensus include presence of abnormal cerebellar anatomy, abnormal neurotransmitter systems, oxidative stress, cerebellar motor and cognitive deficits, and neuroinflammation in subjects with autism. Undefined areas or areas requiring further investigation include lack of treatment options for core symptoms of autism, vermal hypoplasia, and other vermal abnormalities as a consistent feature of autism, mechanisms underlying cerebellar contributions to cognition, and unknown mechanisms underlying neuroinflammation.
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22. Fernandez TV, Sanders SJ, Yurkiewicz IR, Ercan-Sencicek AG, Kim YS, Fishman DO, Raubeson MJ, Song Y, Yasuno K, Ho WS, Bilguvar K, Glessner J, Chu SH, Leckman JF, King RA, Gilbert DL, Heiman GA, Tischfield JA, Hoekstra PJ, Devlin B, Hakonarson H, Mane SM, Gunel M, State MW. {{Rare copy number variants in tourette syndrome disrupt genes in histaminergic pathways and overlap with autism}}. {Biol Psychiatry};2012 (Mar 1);71(5):392-402.
BACKGROUND: Studies of copy number variation (CNV) have characterized loci and molecular pathways in a range of neuropsychiatric conditions. We analyzed rare CNVs in Tourette syndrome (TS) to identify novel risk regions and relevant pathways, to evaluate burden of structural variation in cases versus controls, and to assess overlap of identified variations with those in other neuropsychiatric syndromes. METHODS: We conducted a case-control study of 460 individuals with TS, including 148 parent-child trios and 1131 controls. CNV analysis was undertaken using 370 K to 1 M probe arrays, and genotyping data were used to match cases and controls for ancestry. CNVs present in < 1% of the population were evaluated. RESULTS: While there was no significant increase in the number of de novo or transmitted rare CNVs in cases versus controls, pathway analysis using multiple algorithms showed enrichment of genes within histamine receptor (subtypes 1 and 2) signaling pathways (p = 5.8 x 10(-4) – 1.6 x 10(-2)), as well as axon guidance, cell adhesion, nervous system development, and synaptic structure and function processes. Genes mapping within rare CNVs in TS showed significant overlap with those previously identified in autism spectrum disorders but not intellectual disability or schizophrenia. Three large, likely pathogenic, de novo events were identified, including one disrupting multiple gamma-aminobutyric acid receptor genes. CONCLUSIONS: We identify further evidence supporting recent findings regarding the involvement of histaminergic and gamma-aminobutyric acidergic mechanisms in the etiology of TS and show an overlap of rare CNVs in TS and autism spectrum disorders.
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23. Fleischer AS. {{Support to students with Asperger syndrome in higher education – the perspectives of three relatives and three coordinators}}. {Int J Rehabil Res};2012 (Mar);35(1):54-61.
An increasing number of students with disabilities attend institutes of higher education (HE). Among this group are persons with Asperger syndrome (AS). Persons with AS have a cognitive impairment that can interfere with their studies and the ability to describe their needs and ask for support. This study deals with an assessment of the support services for students with AS from the perspectives of the students’ relatives and the students’ service providers at the universities they attend. The aim of this study was to investigate (a) earlier experiences and events in relation to the transition of students with AS to higher education, according to the relatives’ perceptions of how these experiences and events affect university studies; and (b) the perceptions of both the relatives of students with AS and the coordinators for students with disabilities with respect to the study environment and support for students with AS. The approach is a case study methodology involving relatives and university coordinators for three students with AS. The coordinators’ way of working with students with disabilities is primarily based on the coordinators’ own ideas. No specific organizational routines exist for students with AS. The results reveal that the needs of students with AS have to be made explicit and must be incorporated into the support system. Relatives lack information about the situation and opportunities to engage in collaboration. Universities must adapt the support system to the cognitive impairments experienced by AS students and the difficulties of their everyday lives. The relatives of students with AS may play the central role in supporting the students and in understanding their impairment.Immer mehr behinderte Studenten schlagen einen zweiten Bildungsweg ein. Zu dieser Gruppe zahlen auch Studenten mit Asperger-Syndrom (AS). Personen mit AS sind oftmals kognitiv eingeschrankt, was Auswirkungen auf ihr Studium haben kann, aber auch auf ihre Fahigkeit, ihre Bedurfnisse zu formulieren und um Hilfe zu bitten. Die vorliegende Studie begutachtet die Hilfseinrichtungen fur Studenten mit AS aus der Perspektive der Angehorigen und der Leistungstrager der Studenten an den jeweiligen Universitaten. Ziel der vorliegenden Studie ist (a) die Untersuchung fruherer Erfahrungen und Ereignisse mit Bezug auf den Ubergang von Studenten mit AS zum zweiten Bildungsweg aus der Sicht der Angehorigen und der Auswirkung dieser Erfahrungen und Ereignisse auf das Studium und (b) die Untersuchung der Sichtweise der Angehorigen der Studenten mit AS sowie der Koordinatoren der behinderten Studenten hinsichtlich des Studienumfelds und der Betreuung von Studenten mit AS. Die Studie erfolgte als Fallstudien-Methodik mit Angehorigen und Universitatskoordinatoren fur drei Studenten mit AS. Welche Gestalt die Zusammenarbeit der Koordinatoren mit behinderten Studenten annimmt, beruht primar auf den eigenen Ideen der Koordinatoren. Fur AS-Studenten existiert kein spezieller organisatorischer Ablauf. Die Ergebnisse gaben zu erkennen, dass die Bedurfnisse von AS-Studenten explizit formuliert und in das Betreuungsschema integriert werden mussen. Angehorigen mangelt es an ausfuhrlichen Informationen uber die Situation und an Gelegenheiten zur Eigenbeteiligung. Universitaten mussen ihre Betreuung den Einschrankungen der kognitiven Fahigkeiten der AS-Studenten sowie deren Schwierigkeiten im taglichen Leben anpassen. Den Angehorigen der Studenten mit AS kommt moglicherweise eine zentrale Rolle bei deren Unterstutzung und beim Verstandnis ihrer Behinderung zu.Cada vez es mayor el numero de estudiantes con discapacidades que pueden acceder a estudios de ensenanza superior, entre los cuales se encuentran las personas que padecen el sindrome de Asperger (SA). Las personas con SA presentan una discapacidad cognitiva que puede interferir en sus estudios y en la habilidad para expresar sus necesidades y pedir ayuda. Este estudio consiste en la evaluacion de los servicios de asistencia de los estudiantes con SA desde el punto de vista de sus familiares y del personal de apoyo de las universidades donde estos estudian. El objetivo del estudio fue investigar (a) las experiencias y acontecimientos previos relacionados con la transicion a la ensenanza superior de los estudiantes con SA, de acuerdo con la opinion de sus familiares sobre como dichas experiencias y acontecimientos influyen en los estudios universitarios; y (b) el punto de vista de los familiares de los estudiantes con SA y de los coordinadores de los estudiantes con discapacidades con respecto al entorno de estudio y los servicios de apoyo de los estudiantes con SA. La metodologia utilizada consistio en un estudio de caso donde participaron los familiares y los coordinadores de la universidad de tres estudiantes con SA. El modo en que los coordinadores trabajan con los estudiantes con discapacidades se basa principalmente en sus propios metodos, ya que no existen unos metodos de organizacion especificos para los estudiantes con SA. Los resultados mostraron que las necesidades de los estudiantes con SA deben ser mas explicitas y deben incorporarse en el sistema de los servicios de asistencia. Los familiares no poseen informacion sobre la situacion y las formas en que pueden colaborar. Las universidades deben adaptar el sistema de los servicios de asistencia a las discapacidades cognitivas que sufren los estudiantes con SA y a las dificultades que experimentan en su vida diaria. El papel que desempenan los familiares de los estudiantes con SA debe ser el de apoyo y comprension de la discapacidad que estos padecen.Un nombre croissant d’eleves handicapes frequentent des instituts d’enseignement superieur (ES). On denombre parmi ce groupe des personnes souffrant du syndrome d’Asperger (SA). Ces patients presentent une deficience cognitive qui peut interferer avec leurs etudes et leur capacite a decrire leurs besoins et a demander un soutien. La presente etude porte sur une evaluation des services de soutien a l’attention des etudiants souffrant du SA du point de vue des parents/proches des etudiants et des prestataires de services dans les universites qu’ils frequentent. L’etude avait pour objet d’examiner les experiences et les evenements anterieurs en relation avec la transition de ces eleves vers l’enseignement superieur, selon les perceptions des parents de la maniere dont ces experiences et ces evenements affectent les etudes universitaires, et (b) les perceptions des proches de ces eleves et de leurs coordonnateurs vis-a-vis de l’environnement d’etude et du soutien qui leur est propose. L’approche est une methodologie d’etude de cas impliquant les proches et les coordonnateurs universitaires de trois eleves souffrant du SA. La methode de travail des coordonnateurs avec les etudiants handicapes repose essentiellement sur leurs propres idees du soutien. Aucune routine organisationnelle specifique n’existe pour les etudiants souffrant du SA. Les resultats revelent que les besoins ces eleves doivent etre rendus explicites et etre incorpores dans le systeme de soutien. Les parents/proches manquent d’informations sur la situation et les possibilites d’engager un processus de collaboration. Les universites doivent adapter le systeme de soutien a la deficience cognitive vecue par les etudiants souffrant du SA et les difficultes de leur vie quotidienne. Les proches de ces etudiants peuvent jouer un role central dans le soutien qui leur est apporte et dans la comprehension de leur deficience.
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24. Funabiki Y, Murai T, Toichi M. {{Cortical activation during attention to sound in autism spectrum disorders}}. {Res Dev Disabil};2012 (Mar-Apr);33(2):518-524.
Individuals with autism spectrum disorders (ASDs) can demonstrate hypersensitivity to sounds as well as a lack of awareness of them. Several functional imaging studies have suggested an abnormal response in the auditory cortex of such subjects, but it is not known whether these subjects have dysfunction in the auditory cortex or are simply not listening. We measured changes in blood oxygenated hemoglobin (OxyHb) in the prefrontal and temporal cortices using near-infrared spectroscopy during various listening and ignoring tasks in 11 ASD and 12 control subjects. Here we show that the auditory cortex in ASD subjects responds to sounds fully during attention. OxyHb in the auditory cortex increased with intentional listening but not with ignoring of the same auditory stimulus in a similar fashion in both groups. Cortical responses differed not in the auditory but in the prefrontal region between the ASD and control groups. Thus, unawareness to sounds in ASD could be interpreted as due to inattention rather than dysfunction of the auditory cortex. Difficulties in attention control may account for the contrary behaviors of hypersensitivity and unawareness to sound in ASD.
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25. Gadow KD, Devincent CJ. {{Comparison of Children with Autism Spectrum Disorder with and Without Schizophrenia Spectrum Traits: Gender, Season of Birth, and Mental Health Risk Factors}}. {J Autism Dev Disord};2012 (Feb 24)
Children with autism spectrum disorder (ASD) with and without co-occurring schizophrenia spectrum traits (SST) were examined for differences in co-occurring psychiatric symptoms, background characteristics, and mental health risk factors. Participating mothers and teachers completed a DSM-IV-referenced rating scale and a background questionnaire (mothers only) describing 147 children (6-12 years) with ASD. There was a clear pattern of group differences in co-occurring psychiatric symptom severity (+SST > SST-) and background characteristics. Children with impairing SST had more mental health risk factors. Girls were more likely to be classified SST according to mothers’ ratings. Children born in spring-summer were more likely to be classified non-SST by teachers’ ratings. Findings provide tentative evidence that SST may be a useful marker of behavioral heterogeneity within the ASD clinical phenotype.
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26. Gal G, Abiri L, Reichenberg A, Gabis L, Gross R. {{Time trends in reported autism spectrum disorders in Israel, 1986-2005}}. {J Autism Dev Disord};2012 (Mar);42(3):428-431.
Reports indicate sharp increase in prevalence of autism spectrum disorders (ASD). We aimed to assess the time trend in prevalence of ASD in Israel and describe demographic characteristics of the registered cases. We reviewed the autism registry of the Israeli Ministry of Social Affairs which includes 4,709 cases and identified 4,138 cases born between the years 1986 and 2005. Registered cases were mainly males (84.4%) and Jewish (96.6%). Prevalence data indicated an increase from 1.2 per 1,000 in those born in 1986 to 3.6 per 1,000 in 2003. Greater increase was seen in males, reaching a peak of 5.7 per 1,000, compared to 1.2 per 1,000 in females. Increased ASD prevalence was observed among Israeli children born in 1986-2005.
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27. Gianakopoulos PJ, Zhang Y, Pencea N, Orlic-Milacic M, Mittal K, Windpassinger C, White SJ, Kroisel PM, Chow EW, Saunders CJ, Minassian BA, Vincent JB. {{Mutations in MECP2 exon 1 in classical Rett patients disrupt MECP2_e1 transcription, but not transcription of MECP2_e2}}. {Am J Med Genet B Neuropsychiatr Genet};2012 (Mar);159B(2):210-216.
The overwhelming majority of Rett syndrome cases are caused by mutations in the gene MECP2. MECP2 has two isoforms, termed MECP2_e1 and MECP2_e2, which differ in their N-terminal amino acid sequences. A growing body of evidence has indicated that MECP2_e1 may be the etiologically relevant isoform in Rett Syndrome based on its expression profile in the brain and because, strikingly, no mutations have been discovered that affect MECP2_e2 exclusively. In this study we sought to characterize four classical Rett patients with mutations that putatively affect only the MECP2_e1 isoform. Our hypothesis was that the classical Rett phenotype seen here is the result of disrupted MECP2_e1 expression, but with MECP2_e2 expression unaltered. We used quantitative reverse transcriptase PCR to assay mRNA expression for each isoform independently, and used cytospinning methods to assay total MECP2 in peripheral blood lymphocytes (PBL). In the two Rett patients with identical 11 bp deletions within the coding portion of exon 1, MECP2_e2 levels were unaffected, whilst a significant reduction of MECP2_e1 levels was detected. In two Rett patients harboring mutations in the exon 1 start codon, MECP2_e1 and MECP2_e2 mRNA amounts were unaffected. In summary, we have shown that patients with exon 1 mutations transcribe normal levels of MECP2_e2 mRNA, and most PBL are positive for MeCP2 protein, despite them theoretically being unable to produce the MECP2_e1 isoform, and yet still exhibit the classical RTT phenotype. Altogether, our work further supports our hypothesis that MECP2_e1 is the predominant isoform involved in the neuropathology of Rett syndrome.
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28. Goh S, Peterson BS. {{Imaging evidence for disturbances in multiple learning and memory systems in persons with autism spectrum disorders}}. {Dev Med Child Neurol};2012 (Mar);54(3):208-213.
Aim The aim of this article is to review neuroimaging studies of autism spectrum disorders (ASD) that examine declarative, socio-emotional, and procedural learning and memory systems. Method We conducted a search of PubMed from 1996 to 2010 using the terms ‘autism, »learning, »memory,’ and ‘neuroimaging.’ We limited our review to studies correlating learning and memory function with neuroimaging features of the brain. Results The early literature supports the following preliminary hypotheses: (1) abnormalities of hippocampal subregions may contribute to autistic deficits in episodic and relational memory; (2) disturbances to an amygdala-based network (which may include the fusiform gyrus, superior temporal cortex, and mirror neuron system) may contribute to autistic deficits in socio-emotional learning and memory; and (3) abnormalities of the striatum may contribute to developmental dyspraxia in individuals with ASD. Interpretation Characterizing the disturbances to learning and memory systems in ASD can inform our understanding of the neural bases of autistic behaviors and the phenotypic heterogeneity of ASD.
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29. Gokben S, Ardic UA, Serdaroglu G. {{Use of buspirone and fluoxetine for breathing problems in rett syndrome}}. {Pediatr Neurol};2012 (Mar);46(3):192-194.
Rett syndrome is a severe neurodevelopmental disease with a prevalence of 0.88 per 10,000 girls aged 5-18 years, and is often caused by mutations in methyl-cytosine-phosphate-guanine (CpG)-binding protein 2. Disorder of respiratory control is a prominent feature of Rett syndrome. Brainstem serotoninergic neurons are known to play an important role in the arrangement of breathing rhythm and pattern. We present a patient whose severe hyperventilation and apneic attacks resolved with the concomitant treatment of fluoxetine and buspirone. To our knowledge, we describe the first patient with Rett syndrome to receive fluoxetine for respiratory problems.
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30. Grodberg D, Weinger PM, Kolevzon A, Soorya L, Buxbaum JD. {{Brief report: the autism mental status examination: development of a brief autism-focused exam}}. {J Autism Dev Disord};2012 (Mar);42(3):455-459.
The Autism Mental Status Examination (AMSE) described here is an eight-item observational assessment that prompts the observation and recording of signs and symptoms of autism spectrum disorders (ASD). The AMSE is intended to take place seamlessly in the context of a clinical exam and produces a total score. Subjects were independently administered the AMSE and the Autism Diagnostic Observation Schedule (ADOS). The ADOS was used to estimate the most effective criterion cut-off on the AMSE. A score of five or greater produced excellent sensitivity and good specificity in a high-risk sample. Internal consistency was acceptable and inter-rater reliability was good to excellent. Preliminary findings indicate excellent classification accuracy and suggest that the AMSE provides a rapid and reliable observational assessment in a high-risk population.
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31. Guinchat V, Thorsen P, Laurent C, Cans C, Bodeau N, Cohen D. {{Pre-, peri- and neonatal risk factors for autism}}. {Acta Obstet Gynecol Scand};2012 (Mar);91(3):287-300.
Objective. To identify pre-, peri- and neonatal risk factors for pervasive developmental disorders (PDD). Methods. We searched the Medline database through March 2011 for relevant case-control and population-based studies on pre-, peri- and neonatal hazards related to PDD, including autism. We identified 85 studies for this review. Data were extracted systematically and organized according to risk factors related to family history, pregnancy, gestational age, delivery, birth milestones and the neonate’s condition at birth. Results. During the prenatal period, risk factors for PDD were advanced maternal or paternal ages, being firstborn vs. third or later, maternal prenatal medication use and mother’s status as foreign born. During the perinatal and neonatal periods, the risk factors for PDD were preterm birth, breech presentation, planned cesarean section, low Apgar scores, hyperbilirubinemia, birth defect and a birthweight small for gestational age. The influence of maternal pre-eclampsia, diabetes, vomiting, infections and stress during pregnancy requires further study in order to determine risk for PDD. Discussion. Despite evidence for the association of some pre-, peri- and neonatal risk factors associated with PDD, it remains unclear whether these risks are causal or play a secondary role in shaping clinical expression in individuals with genetic vulnerability. A plausible hypothsesis is that improvements in obstetric and neonatal management have led to an increased rate of survivors with pre-existing brain damage. Given the variety of risk factors, we propose that future studies should investigate combinations of multiple factors, rather than focusing on a single factor.
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32. Higashida H, Yokoyama S, Huang JJ, Liu L, Ma WJ, Akther S, Higashida C, Kikuchi M, Minabe Y, Munesue T. {{Social memory, amnesia, and autism: Brain oxytocin secretion is regulated by NAD(+) metabolites and single nucleotide polymorphisms of CD38}}. {Neurochem Int};2012 (Feb 13)
Previously, we demonstrated that CD38, a transmembrane protein with ADP-ribosyl cyclase activity, plays a critical role in mouse social behavior by regulating the release of oxytocin (OXT), which is essential for mutual recognition. When CD38 was disrupted, social amnesia was observed in Cd38 knockout mice. The autism spectrum disorders (ASDs), characterized by defects in reciprocal social interaction and communication, occur either sporadically or in a familial pattern. However, the etiology of ASDs remains largely unknown. Therefore, the theoretical basis for pharmacological treatments has not been established. Hence, there is a rationale for investigating single nucleotide polymorphisms (SNPs) in the human CD38 gene in ASD subjects. We found several SNPs in this gene. The SNP rs3796863 (C>A) was associated with high-functioning autism (HFA) in American samples from the Autism Gene Resource Exchange. Although this finding was partially confirmed in low-functioning autism subjects in Israel, it has not been replicated in Japanese HFA subjects. The second SNP of interest, rs1800561 (4693C>T), leads to the substitution of an arginine (R) at codon 140 by tryptophan (W; R140W) in CD38. This mutation was found in four probands of ASD and in family members of three pedigrees with variable levels of ASD or ASD traits. The plasma levels of OXT in ASD subjects with the R140W allele were lower than those in ASD subjects lacking this allele. The OXT levels were unchanged in healthy subjects with or without this mutation. One proband with the R140W allele receiving intranasal OXT for approximately 3years showed improvement in areas of social approach, eye contact and communication behaviors, emotion, irritability, and aggression. Five other ASD subjects with mental deficits received nasal OXT for various periods; three subjects showed improved symptoms, while two showed little or no effect. These results suggest that SNPs in CD38 may be possible risk factors for ASD by abrogating OXT function and that some ASD subjects can be treated with OXT in preliminary clinical trials.
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33. Hutchins TL, Prelock PA, Bonazinga L. {{Psychometric Evaluation of the Theory of Mind Inventory (ToMI): A Study of Typically Developing Children and Children with Autism Spectrum Disorder}}. {J Autism Dev Disord};2012 (Mar);42(3):327-341.
Two studies examined the psychometric properties of the Theory of Mind Inventory (ToMI). In Study One, 135 caregivers completed the ToMI for children (ages 3 through 17) with autism spectrum disorder (ASD). Findings revealed excellent test-retest reliability and internal consistency. Principle Components Analysis revealed three subscales related to the complexity of ToM understanding. In Study Two, data were collected for 124 typically developing children (2 through 12 years). Findings again revealed excellent test-retest and internal consistency. The ToMI distinguished groups by age (younger vs. older children) and developmental status (typically developing vs. ASD), and predicted child performance on a ToM task battery. Utility of the ToMI, study limitations and directions for future research are discussed.
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34. Ingersoll B, Meyer K, Bonter N, Jelinek S. {{A Comparison of Developmental, Social-Pragmatic and Naturalistic Behavioral Interventions on Language Use and Social Engagement in Children with Autism}}. {J Speech Lang Hear Res};2012 (Feb 21)
PURPOSE: Developmental, social pragmatic (DSP) and naturalistic behavioral interventions share a number of features, but differ in their use of facilitative strategies and direct elicitation of child language. This study investigated whether these approaches produce different language and social outcomes in young children with autism. METHOD: An ABACAD design was used to compare the effects of a DSP, naturalistic behavioral, and combined intervention on language type and function and social engagement in five children with autism. RESULTS: Milieu teaching and the combined intervention produced higher rates of language targets than responsive interaction. An analysis of the type and function of language targets suggested differences between conditions were driven primarily by prompted, and to a lesser extent, spontaneous requests. Social engagement ratings were higher during each intervention than baseline, but differences between treatment conditions were not consistent across children. CONCLUSIONS: For children with autism, naturalistic interventions that use direct elicitation of child language lead to greater short term gains in the use of expressive language targets, particularly prompted requests, than interventions that use facilitative strategies only. All three naturalistic language interventions can promote social engagement. For some children, the combined use of direct elicitation and responsiveness-based strategies may enhance treatment response.
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35. Itoh M, Tahimic CG, Ide S, Otsuki A, Sasaoka T, Noguchi S, Oshimura M, Goto YI, Kurimasa A. {{Methyl CpG-binding Protein Isoform MeCP2_e2 Is Dispensable for Rett Syndrome Phenotypes but Essential for Embryo Viability and Placenta Development}}. {J Biol Chem};2012 (Feb 28)
Methyl CpG-binding protein 2 (MeCP2) mutations are implicated in Rett syndrome (RTT), one of the common causes of female mental retardation. Two MeCP2 isoforms have been reported: MeCP2_e2, splicing of all four exons and MeCP2_e1, alternative splicing of exons 1, 3 and 4. Their relative expression levels vary among tissues, with MeCP2_e1 being more dominant in adult brain while MeCP2_e2 is expressed more abundantly in placenta, liver, and skeletal muscle. In this study, we performed specific disruption of the MeCP2_e2-defining exon 2 using Cre-LoxP system and examined the consequences of selective loss of MeCP2_e2 function in vivo. We performed behavior evaluation, gene-expression analysis, using RT-PCR and real time quantitative PCR, and histological analysis. We demonstrate that selective deletion of MeCP2_e2 does not result in RTT-associated neurological phenotypes but confers a survival disadvantage to embryos carrying MeCP2_e2 null allele of maternal origin. In addition, we reveal a specific requirement for MeCP2_e2 function in extraembryonic tissue where selective loss of MeCP2_e2 results in placenta defects and upregulation of peg-1 as determined by the parental origin of the mutant allele. Taken together, our findings suggest a novel role for MeCP2 in normal placenta development and illustrate how paternal X chromosome inactivation in extraembryonic tissues confers a survival disadvantage for carriers of a mutant maternal MeCP2_e2 allele. Moreover, our findings provide an explanation for the absence of reports on MeCP2_e2-specific exon 2 mutations in RTT. MeCP2_e2 mutations in humans may result in a phenotype that evades a diagnosis of RTT.
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36. Jaarsma P, Welin S. {{Autism as a natural human variation: reflections on the claims of the neurodiversity movement}}. {Health Care Anal};2012 (Mar);20(1):20-30.
Neurodiversity has remained a controversial concept over the last decade. In its broadest sense the concept of neurodiversity regards atypical neurological development as a normal human difference. The neurodiversity claim contains at least two different aspects. The first aspect is that autism, among other neurological conditions, is first and foremost a natural variation. The other aspect is about conferring rights and in particular value to the neurodiversity condition, demanding recognition and acceptance. Autism can be seen as a natural variation on par with for example homosexuality. The broad version of the neurodiversity claim, covering low-functioning as well as high-functioning autism, is problematic. Only a narrow conception of neurodiversity, referring exclusively to high-functioning autists, is reasonable. We will discuss the effects of DSM categorization and the medical model for high functioning autists. After a discussion of autism as a culture we will analyze various possible strategies for the neurodiversity movement to claim extra resources for autists as members of an underprivileged culture without being labelled disabled or as having a disorder. We will discuss their vulnerable status as a group and what obligation that confers on the majority of neurotypicals.
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37. James WH. {{A potential explanation of some established major risk factors for autism}}. {Dev Med Child Neurol};2012 (Feb 28)
Baron-Cohen hypothesized that a cause of autism in infants is exposure to high concentrations of intrauterine testosterone concentrations. Some of the subsequent research on this hypothesis has focused on the possibility that the source of this testosterone is the fetus; however, this review shows that if the source is taken to be the mother, then many of the established risk factors for autism could be explained. If that were correct, it would follow that high maternally derived intrauterine androgen concentrations may be a major environmental cause of autism.
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38. Kalbfleisch ML, Loughan AR. {{Impact of IQ Discrepancy on Exec
