1. Driessen TM, Eisinger BE, Zhao C, Stevenson SA, Saul MC, Gammie SC. {{Genes showing altered expression in the medial preoptic area in the highly social maternal phenotype are related to autism and other disorders with social deficits}}. {BMC neuroscience}. 2014 Jan 14;15(1):11.
BACKGROUND: The mother-child relationship is the most fundamental social bond in mammals, and previous studies indicate that the medial preoptic area (MPOA) contributes to this increase in sociability. It is possible that the same genes that lead to elevated sociability in one condition (the maternal state) might also be dysregulated in some disorders with social deficits (e.g. autism). In this study, we examined whether there was enrichment (greater than chance overlap) for social deficit disorder related genes in MPOA microarray results between virgin and postpartum female mice. We utilized microarrays to assess large scale gene expression changes in the MPOA of virgin and postpartum mice. The Modular Single Set Enrichment Test (MSET) was used to determine if mental health disorder related genes were enriched in significant microarray results. Additional resources, such as ToppCluster, NIH DAVID, and weighted co-expression network analysis (WGCNA) were used to analyze enrichment for specific gene clusters or indirect relationships between significant genes of interest. Finally, a subset of microarray results was validated using quantitative PCR. RESULTS: Significant postpartum MPOA microarray results were enriched for multiple disorders that include social deficits, including autism, bipolar disorder, depression, and schizophrenia. Together, 98 autism-related genes were identified from the significant microarray results. Further, ToppCluser and NIH DAVID identified a large number of postpartum genes related to ion channel activity and CNS development, and also suggested a role for microRNAs in regulating maternal gene expression. WGCNA identified a module of genes associated with the postpartum phenotype, and identified indirect links between transcription factors and other genes of interest. CONCLUSION: The transition to the maternal state involves great CNS plasticity and increased sociability. We identified multiple novel genes that overlap between the postpartum MPOA (high sociability) and mental health disorders with low sociability. Thus, the activity or interactions of the same genes may be altering social behaviors in different directions in different conditions. Maternity also involves elevated risks for disorders, including depression, psychosis, and BPD, so identification of maternal genes common to these disorders may provide insights into the elevated vulnerability of the maternal brain.
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2. Eilam-Stock T, Xu P, Cao M, Gu X, Van Dam NT, Anagnostou E, Kolevzon A, Soorya L, Park Y, Siller M, He Y, Hof PR, Fan J. {{Abnormal autonomic and associated brain activities during rest in autism spectrum disorder}}. {Brain : a journal of neurology}. 2014 Jan;137(Pt 1):153-71.
Autism spectrum disorders are associated with social and emotional deficits, the aetiology of which are not well understood. A growing consensus is that the autonomic nervous system serves a key role in emotional processes, by providing physiological signals essential to subjective states. We hypothesized that altered autonomic processing is related to the socio-emotional deficits in autism spectrum disorders. Here, we investigated the relationship between non-specific skin conductance response, an objective index of sympathetic neural activity, and brain fluctuations during rest in high-functioning adults with autism spectrum disorder relative to neurotypical controls. Compared with control participants, individuals with autism spectrum disorder showed less skin conductance responses overall. They also showed weaker correlations between skin conductance responses and frontal brain regions, including the anterior cingulate and anterior insular cortices. Additionally, skin conductance responses were found to have less contribution to default mode network connectivity in individuals with autism spectrum disorders relative to controls. These results suggest that autonomic processing is altered in autism spectrum disorders, which may be related to the abnormal socio-emotional behaviours that characterize this condition.
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3. Gatto CL, Pereira D, Broadie K. {{GABAergic circuit dysfunction in the Drosophila Fragile X syndrome model}}. {Neurobiology of disease}. 2014 Jan 11.
Fragile X syndrome (FXS), caused by loss of FMR1 gene function, is the most common heritable cause of intellectual disability and autism spectrum disorders. The FMR1 protein (FMRP) translational regulator mediates activity-dependent control of synapses. In addition to the metabotropic glutamate receptor (mGluR) hyperexcitation FXS theory, the GABA theory postulates that hypoinhibition is causative for disease state symptoms. Here, we use the Drosophila FXS model to assay central brain GABAergic circuitry, especially within the Mushroom Body (MB) learning center. All 3 GABAA receptor (GABAAR) subunits are reportedly downregulated in dfmr1 null brains. We demonstrate parallel downregulation of glutamic acid decarboxylase (GAD), the rate-limiting GABA synthesis enzyme, although GABAergic cell numbers appear unaffected. Mosaic analysis with a repressible cell marker (MARCM) single-cell clonal studies show that dfmr1 null GABAergic neurons innervating the MB calyx display altered architectural development, with early underdevelopment followed by later overelaboration. In addition, a new class of extra-calyx terminating GABAergic neurons is shown to include MB intrinsic alpha/beta Kenyon Cells (KCs), revealing a novel level of MB inhibitory regulation. Functionally, dfmr1 null GABAergic neurons exhibit elevated calcium signaling and altered kinetics in response to acute depolarization. To test the role of these GABAergic changes, we attempted to pharmacologically restore GABAergic signaling and assay effects on the compromised MB-dependent olfactory learning in dfmr1 mutants, but found no improvement. Our results show that GABAergic circuit structure and function are impaired in the FXS disease state, but that correction of hypoinhibition alone is not sufficient to rescue a behavioral learning impairment.
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4. Hadjikhani N, Zurcher NR, Rogier O, Hippolyte L, Lemonnier E, Ruest T, Ward N, Lassalle A, Gillberg N, Billstedt E, Helles A, Gillberg C, Solomon P, Prkachin KM, Gillberg C. {{Emotional contagion for pain is intact in autism spectrum disorders}}. {Translational psychiatry}. 2014;4:e343.
Perceiving others in pain generally leads to empathic concern, consisting of both emotional and cognitive processes. Empathy deficits have been considered as an element contributing to social difficulties in individuals with autism spectrum disorders (ASD). Here, we used functional magnetic resonance imaging and short video clips of facial expressions of people experiencing pain to examine the neural substrates underlying the spontaneous empathic response to pain in autism. Thirty-eight adolescents and adults of normal intelligence diagnosed with ASD and 35 matched controls participated in the study. In contrast to general assumptions, we found no significant differences in brain activation between ASD individuals and controls during the perception of pain experienced by others. Both groups showed similar levels of activation in areas associated with pain sharing, evidencing the presence of emotional empathy and emotional contagion in participants with autism as well as in controls. Differences between groups could be observed at a more liberal statistical threshold, and revealed increased activations in areas involved in cognitive reappraisal in ASD participants compared with controls. Scores of emotional empathy were positively correlated with brain activation in areas involved in embodiment of pain in ASD group only. Our findings show that simulation mechanisms involved in emotional empathy are preserved in high-functioning individuals with autism, and suggest that increased reappraisal may have a role in their apparent lack of caring behavior.
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5. Magiati I, Tay XW, Howlin P. {{Cognitive, language, social and behavioural outcomes in adults with autism spectrum disorders: A systematic review of longitudinal follow-up studies in adulthood}}. {Clinical psychology review}. 2013 Dec 4;34(1):73-86.
BACKGROUND: Although increasing numbers of children diagnosed with Autism Spectrum Disorders (ASD) are now entering adolescence and adulthood, there is limited research on outcomes post childhood. A systematic review of the existing literature was conducted. METHOD: PsycINFO, PubMed, MedLine and CINAHL were systematically searched using keywords related to ASD and adolescent and adult outcomes. Studies of individuals diagnosed with ASD in childhood and followed up into adulthood were identified and reviewed. Only studies with samples sizes >10, mean age at outcome >16years and at least one previous assessment in childhood (<16years) were included. RESULTS: Twenty-five studies meeting criteria were identified. Reported outcomes in adulthood were highly variable across studies. Although social functioning, cognitive ability and language skills remained relatively stable in some studies, others reported deterioration over time. Adaptive functioning tended to improve in most studies. Diagnosis of autism or ASD was generally stable, although severity of autism-related behavioural symptoms was often reported to improve. Childhood IQ and early language ability appeared to be the strongest predictors of later outcome, but few studies examined other early variables associated with adult functioning. DISCUSSION: Implications of the findings are discussed in relation to methodological challenges in longitudinal outcome research and future research directions.
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6. Manderscheid R. {{The Affordable Care Act: Overview and Implications for County and City Behavioral Health and Intellectual/Developmental Disability Programs}}. {Journal of social work in disability & rehabilitation}. 2014 Jan 14.
The author begins by reviewing the five key intended actions of the Affordable Care Act (ACA)-insurance reform, coverage reform, quality reform, performance reform, and Information Technology (IT) reform. This framework provides a basis for examining how populations served and service programs will change at the county and city levels as a result of the ACA, and how provider staff also will change over time as a result of these developments. The author concludes by outlining immediate next steps for county and city programs.
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7. Ronemus M, Iossifov I, Levy D, Wigler M. {{The role of de novo mutations in the genetics of autism spectrum disorders}}. {Nature reviews Genetics}. 2014 Feb;15(2):133-41.
The identification of the genetic components of autism spectrum disorders (ASDs) has advanced rapidly in recent years, particularly with the demonstration of de novo mutations as an important source of causality. We review these developments in light of genetic models for ASDs. We consider the number of genetic loci that underlie ASDs and the relative contributions from different mutational classes, and we discuss possible mechanisms by which these mutations might lead to dysfunction. We update the two-class risk genetic model for autism, especially in regard to children with high intelligence quotients.
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8. Shelton AL, Cornish K, Kraan C, Georgiou-Karistianis N, Metcalfe SA, Bradshaw JL, Hocking DR, Archibald AD, Cohen J, Trollor JN, Fielding J. {{Exploring inhibitory deficits in female premutation carriers of fragile X syndrome: Through eye movements}}. {Brain and cognition}. 2014 Jan 11;85C:201-8.
There is evidence which demonstrates that a subset of males with a premutation CGG repeat expansion (between 55 and 200 repeats) of the fragile X mental retardation 1 gene exhibit subtle deficits of executive function that progressively deteriorate with increasing age and CGG repeat length. However, it remains unclear whether similar deficits, which may indicate the onset of more severe degeneration, are evident in female PM-carriers. In the present study we explore whether female PM-carriers exhibit deficits of executive function which parallel those of male PM-carriers. Fourteen female fragile X premutation carriers without fragile X-associated tremor/ataxia syndrome and fourteen age, sex, and IQ matched controls underwent ocular motor and neuropsychological tests of select executive processes, specifically of response inhibition and working memory. Group comparisons revealed poorer inhibitory control for female premutation carriers on ocular motor tasks, in addition to demonstrating some difficulties in behaviour self-regulation, when compared to controls. A negative correlation between CGG repeat length and antisaccade error rates for premutation carriers was also found. Our preliminary findings indicate that impaired inhibitory control may represent a phenotype characteristic which may be a sensitive risk biomarker within this female fragile X premutation population.
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9. Stefansson H, Meyer-Lindenberg A, Steinberg S, Magnusdottir B, Morgen K, Arnarsdottir S, Bjornsdottir G, Walters GB, Jonsdottir GA, Doyle OM, Tost H, Grimm O, Kristjansdottir S, Snorrason H, Davidsdottir SR, Gudmundsson LJ, Jonsson GF, Stefansdottir B, Helgadottir I, Haraldsson M, Jonsdottir B, Thygesen JH, Schwarz AJ, Didriksen M, Stensbol TB, Brammer M, Kapur S, Halldorsson JG, Hreidarsson S, Saemundsen E, Sigurdsson E, Stefansson K. {{CNVs conferring risk of autism or schizophrenia affect cognition in controls}}. {Nature}. 2014 Jan 16;505(7483):361-6.
In a small fraction of patients with schizophrenia or autism, alleles of copy-number variants (CNVs) in their genomes are probably the strongest factors contributing to the pathogenesis of the disease. These CNVs may provide an entry point for investigations into the mechanisms of brain function and dysfunction alike. They are not fully penetrant and offer an opportunity to study their effects separate from that of manifest disease. Here we show in an Icelandic sample that a few of the CNVs clearly alter fecundity (measured as the number of children by age 45). Furthermore, we use various tests of cognitive function to demonstrate that control subjects carrying the CNVs perform at a level that is between that of schizophrenia patients and population controls. The CNVs do not all affect the same cognitive domains, hence the cognitive deficits that drive or accompany the pathogenesis vary from one CNV to another. Controls carrying the chromosome 15q11.2 deletion between breakpoints 1 and 2 (15q11.2(BP1-BP2) deletion) have a history of dyslexia and dyscalculia, even after adjusting for IQ in the analysis, and the CNV only confers modest effects on other cognitive traits. The 15q11.2(BP1-BP2) deletion affects brain structure in a pattern consistent with both that observed during first-episode psychosis in schizophrenia and that of structural correlates in dyslexia.
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10. van Urk PR, van den Berg MP, van Royen BJ, Smeets EE, Curfs LM. {{[Rett syndrome]}}. {Nederlands tijdschrift voor geneeskunde}. 2014;158(3):A6686.
BACKGROUND: Rett syndrome is caused by mutations in the X-linked MECP2 gene, encoding MeCP2 protein. This protein is essential for the transcription and repression of other genes and is important for the development and plasticity of the central nervous system. Children with Rett syndrome initially develop normally but after a few months their development deteriorates. CASE DESCRIPTION: The case describes a girl aged 3 years 7 months whose development had initially been normal but then stagnated and was followed by a phase of regression. Her speech was lost and she developed severe dyspraxia with stereotypic hand movements characteristic of the condition. The clinical diagnosis of Rett syndrome was confirmed through genetic testing. Later on she developed epileptic seizures and a severe scoliosis for which surgical correction and stabilisation was carried out. CONCLUSION: Rett syndrome is a severe neurological developmental disorder that occurs almost exclusively in females and for which there is still no causal treatment. The treatment is multidisciplinary and based on clinical experience.
11. Williams K, Woolfenden S, Roberts J, Rodger S, Bartak L, Prior M. {{Autism in context 2: Assessment, intervention and services in Australia}}. {Journal of paediatrics and child health}. 2014 Jan 14.
Continuing from part 1, part 2 of the autism spectrum disorders review explores clinical practice and service delivery aspects of autism spectrum disorders including current assessment approaches in Australia, family-centred models of care, and key service structure and delivery issues. Treatments including behavioural interventions, established and emergent medication, and complementary and alternative therapies are discussed. The key role of paediatricians as both individual child and family care providers and advocates, as well as agents of service reform in Australia, is evident. Much still needs to be done.
