1. Bongmba OY, Martinez LA, Elhardt ME, Butler K, Tejada-Simon MV. {{Modulation of dendritic spines and synaptic function by Rac1: A possible link to Fragile X syndrome pathology}}. {Brain Res};2011 (Jul 5);1399:79-95.
Rac1, a protein of the Rho GTPase subfamily, has been implicated in neuronal and spine development as well as the formation of synapses with appropriate partners. Dendrite and spine abnormalities have been implicated in several psychiatric disorders such as Fragile X syndrome, where neurons show a high density of long, thin, and immature dendritic spines. Although abnormalities in dendrites and spines have been correlated with impaired cognitive abilities in mental retardation, the causes of these malformations are not yet well understood. Fragile X syndrome is the most common type of inherited mental retardation caused by the absence of FMRP protein, a RNA-binding protein implicated in the regulation of mRNA translation and transport, leading to protein synthesis. We suggest that FMRP might act as a negative regulator on the synthesis of Rac1. Maintaining an optimal level of Rac1 and facilitating the reorganization of the cytoskeleton likely leads to normal neuronal morphology during activity-dependent plasticity. In our study, we first demonstrated that Rac1 is not only associated but necessary for normal spine development and long-term synaptic plasticity. We further showed that, in Fmr1 knockout mice, lack of FMRP induces an overactivation of Rac1 in the mouse brain and other organs that have been shown to be altered in Fragile X syndrome. In those animals, pharmacological manipulation of Rac1 partially reverses their altered long-term plasticity. Thus, regulation of Rac1 may provide a functional link among deficient neuronal morphology, aberrant synaptic plasticity and cognition impairment in Fragile X syndrome.
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2. Cebula KR. {{Applied Behavior Analysis Programs for Autism: Sibling Psychosocial Adjustment During and Following Intervention Use}}. {J Autism Dev Disord};2011 (Jul 2)
Psychosocial adjustment in siblings of children with autism whose families were using a home-based, applied behavior analysis (ABA) program was compared to that of siblings in families who were not using any intensive autism intervention. Data gathered from parents, siblings and teachers indicated that siblings in ABA families experienced neither significant drawbacks nor benefits in terms of their behavioral adjustment, sibling relationship quality and self-concept compared to control group siblings, either during or following intervention use. Parents and siblings perceived improvements in sibling interaction since the outset of ABA, with parents somewhat more positive in their views than were siblings. Social support was associated with better sibling outcomes in all groups. Implications for supporting families using ABA are considered.
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3. Creten C, van der Zwaan S, Blankespoor RJ, Maatkamp A, Nicolai J, van Os J, Schieveld JN. {{Late onset autism and anti-NMDA-receptor encephalitis}}. {Lancet};2011 (Jul 2);378(9785):98.
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4. Levitt P. {{Serotonin and the Autisms: A Red Flag or a Red Herring?}}. {Arch Gen Psychiatry};2011 (Jul 5)
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5. Rojas DC, Teale PD, Maharajh K, Kronberg E, Youngpeter K, Wilson L, Wallace A, Hepburn S. {{Transient and steady-state auditory gamma-band responses in first-degree relatives of people with autism spectrum disorder}}. {Mol Autism};2011 (Jul 5);2(1):11.
ABSTRACT: BACKGROUND: Stimulus-related gamma-band oscillations, which may be related to perceptual binding, are reduced in persons with autism spectrum disorders (ASD). The purpose of this study was to examine auditory transient and steady-state gamma-band findings in 1st degree relatives of persons with ASD to assess their potential familiality in ASD. METHODS: Magnetoencephalography (MEG) recordings in 21 parents of a child with an autism spectrum disorder (pASD) and 20 healthy adult control subjects (HC) were obtained. Gamma-band phase locking factor (PLF), evoked and induced amplitudes to 32, 40 and 48 Hz amplitude-modulated sounds were measured for transient and steady-state responses. Participants were also tested on a number of behavioral and cognitive assessments related to the broad autism phenotype (BAP). RESULTS: Reliable group differences were observed primarily for steady-state responses. In the left hemisphere, pASD subjects exhibited lower phase-locked steady-state amplitudes in all three conditions. Total gamma-band amplitude, including the non-phase-locked component, was also reduced in the pASD group. In addition, pASD subjects had significantly lower PLF than the HC group. Correlations were observed between MEG measures and BAP measures. CONCLUSIONS: The reduction in steady-state gamma-band responses in the pASD group is consistent with prior results for children with ASD. Steady-state responses may be more sensitive to phase-locking errors in ASD than transient responses. Together with the lower PLF and phase-locked amplitudes in 1st degree relatives, correlations between gamma-band measures and behavioral measures relevant to the BAP highlight the potential of gamma-band deficits as a potential new autism endophenotype.
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6. Schieve LA, Boulet SL, Kogan MD, Yeargin-Allsopp M, Boyle CA, Visser SN, Blumberg SJ, Rice C. {{Parenting aggravation and autism spectrum disorders: 2007 National Survey of Children’s Health}}. {Disabil Health J};2011 (Jul);4(3):143-152.
BACKGROUND: Studies suggest autism spectrum disorders (ASDs) are associated with high parenting stress and aggravation. Research on specific risk factors is needed. OBJECTIVE/HYPOTHESES: To assess aggravation level among parents of children with and without ASDs. METHODS: The sample of 73,030 children aged 4 to 17 years in the 2007 National Survey of Children’s Health and their parent respondents were divided into mutually exclusive groups based on child ASD status and other special health care needs. Adjusted prevalence ratios (aPR) for associations between a high Aggravation in Parenting scale score and various risk factors were computed from multivariable models. RESULTS: High-aggravation percentages were comparable for parents of children with a current ASD (36.6%), ASD reported previously but not currently (35.2%), and another (non-ASD) developmental problem (31.2%) but were significantly lower for parents of children with other special health care needs (6.5%) and no special health care needs (5.1%). Within the current-ASD group, high aggravation was associated with young child age (aPR = 1.8 [1.2-2.6]), lack of health insurance (aPR = 1.5 [1.0-2.4]), lack of a medical home (aPR = 2.2 [1.4-3.5]), recent child mental health treatment (aPR = 2.1 [1.5-3.0]), lack of parenting emotional support (aPR = 1.5 [1.1-2.1]), and ASD severity (aPR = 1.4 [1.0-1.6]). Some of these same factors were associated with aggravation in the non-ASD groups. However, the medical home finding was specific to the ASD groups. CONCLUSIONS: Parenting a child with ASD is associated with high aggravation; however, there is variability within health care and social support subgroups. Strategies to strengthen medical home components for children with ASDs should be considered.
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7. Schipul SE, Williams DL, Keller TA, Minshew NJ, Just MA. {{Distinctive Neural Processes during Learning in Autism}}. {Cereb Cortex};2011 (Jul 1)
This functional magnetic resonance imaging study compared the neural activation patterns of 18 high-functioning individuals with autism and 18 IQ-matched neurotypical control participants as they learned to perform a social judgment task. Participants learned to identify liars among pairs of computer-animated avatars uttering the same sentence but with different facial and vocal expressions, namely those that have previously been associated with lying versus truth-telling. Despite showing a behavioral learning effect similar to the control group, the autism group did not show the same pattern of decreased activation in cortical association areas as they learned the task. Furthermore, the autism group showed a significantly smaller increase in interregion synchronization of activation (functional connectivity) with learning than did the control group. Finally, the autism group had decreased structural connectivity as measured by corpus callosum size, and this measure was reliably related to functional connectivity measures. The findings suggest that cortical underconnectivity in autism may constrain the ability of the brain to rapidly adapt during learning.
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8. Szatmari P. {{Is Autism, at Least in Part, a Disorder of Fetal Programming?}}. {Arch Gen Psychiatry};2011 (Jul 5)
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9. Winsor JE, Butterworth J, Boone J. {{Jobs by 21 partnership project: impact of cross-system collaboration on employment outcomes of young adults with developmental disabilities}}. {Intellect Dev Disabil};2011 (Aug);49(4):274-284.
Abstract In 2007, the low level of young adults with developmental disabilities who were employed in the 3 months postgraduation from high school led the Washington State legislature to authorize and fund the Jobs by 21 Partnership Project. The intent of the project was to identify and demonstrate best practices in sustainable partnerships among Washington State’s school and adult service systems. Results indicated that participants in the project were more likely to be employed following school exit and had stronger employment outcomes than students who did not participate. Further, data suggest that improved employment outcomes were supported by the leveraging and maximization of financial and in-kind resources and the strengthening of collaborative relationships across project stakeholders.
