Pubmed du 11/06/15

Pubmed du jour

2015-06-11 12:03:50

1. Azad G, Mandell DS. {{Concerns of parents and teachers of children with autism in elementary school}}. {Autism};2015 (Jun 11)
Many consensus guidelines encourage parents and teachers to openly communicate about their concerns regarding their children. These guidelines attest to the importance of achieving consensus about what issues are most critical and how to address them. The purpose of this study was to examine whether parents and teachers (1) agree about their concerns for their children with autism and (2) when given the opportunity, whether they discussed these concerns. Participants were 39 parent-teacher dyads of children with autism in kindergarten-through-fifth grade autism support classrooms. Each parent and teacher was interviewed separately about their concerns and then observed together in a discussion about the child. Parents and teachers generally agreed about their primary and secondary concerns. When given an opportunity to communicate their concerns, 49% of the parent-teacher dyads discussed problems that neither reported as their primary concern, and 31% discussed problems that neither reported as their primary or secondary concern. These findings suggest that interventions should target parent-teacher communication, rather than agreement, to facilitate home-school collaboration.

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2. Beadle-Brown J, Bigby C, Bould E. {{Observing practice leadership in intellectual and developmental disability services}}. {J Intellect Disabil Res};2015 (Jun 8)
BACKGROUND: Improving staff performance is an issue in services for people with intellectual disability. Practice leadership, where the front line leader of a staff team focuses on service user outcomes in everything they do and provides coaching, modeling, supervision and organisation to the team, has been identified as important in improving staff performance. To date this finding is based only on self-report measures. METHODS: This paper describes and tests an observational measure of practice leadership based on an interview with the front-line manager, a review of paperwork and observations in 58 disability services in Australia. RESULTS: The measure showed good internal consistency and acceptable inter-rater reliability. Practice leadership was associated with staff practice and outcomes for service users. The observed measure of practice leadership appears to be a useful tool for assessing whether leadership within a service promotes enabling and empowering support by staff. It was found to discriminate higher and lower performing services in terms of active support. CONCLUSIONS: The measure had good reliability and validity although some further testing is required to give a complete picture of the possible uses and reliability of the measure. The measure is potentially useful in contexts of both research and service development. The confirmation of previous findings from self-report measures that practice leadership is related to the quality of staff practice and outcomes for service users has implications for policy and practice in terms of the training of managers and structures for organisational management.

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3. Broderick N, Wade JL, Meyer JP, Hull M, Reeve RE. {{Model Invariance Across Genders of the Broad Autism Phenotype Questionnaire}}. {J Autism Dev Disord};2015 (Jun 11)
ASD is one of the most heritable neuropsychiatric disorders, though comprehensive genetic liability remains elusive. To facilitate genetic research, researchers employ the concept of the broad autism phenotype (BAP), a milder presentation of traits in undiagnosed relatives. Research suggests that the BAP Questionnaire (BAPQ) demonstrates psychometric properties superior to other self-report measures. To examine evidence regarding validity of the BAPQ, the current study used confirmatory factor analysis to test the assumption of model invariance across genders. Results of the current study upheld model invariance at each level of parameter constraint; however, model fit indices suggested limited goodness-of-fit between the proposed model and the sample. Exploratory analyses investigated alternate factor structure models but ultimately supported the proposed three-factor structure model.

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4. Cerliani L, Mennes M, Thomas RM, Di Martino A, Thioux M, Keysers C. {{Increased Functional Connectivity Between Subcortical and Cortical Resting-State Networks in Autism Spectrum Disorder}}. {JAMA Psychiatry};2015 (Jun 10)
Importance: Individuals with autism spectrum disorder (ASD) exhibit severe difficulties in social interaction, motor coordination, behavioral flexibility, and atypical sensory processing, with considerable interindividual variability. This heterogeneous set of symptoms recently led to investigating the presence of abnormalities in the interaction across large-scale brain networks. To date, studies have focused either on constrained sets of brain regions or whole-brain analysis, rather than focusing on the interaction between brain networks. Objectives: To compare the intrinsic functional connectivity between brain networks in a large sample of individuals with ASD and typically developing control subjects and to estimate to what extent group differences would predict autistic traits and reflect different developmental trajectories. Design, Setting, and Participants: We studied 166 male individuals (mean age, 17.6 years; age range, 7-50 years) diagnosed as having DSM-IV-TR autism or Asperger syndrome and 193 typical developing male individuals (mean age, 16.9 years; age range, 6.5-39.4 years) using resting-state functional magnetic resonance imaging (MRI). Participants were matched for age, IQ, head motion, and eye status (open or closed) in the MRI scanner. We analyzed data from the Autism Brain Imaging Data Exchange (ABIDE), an aggregated MRI data set from 17 centers, made public in August 2012. Main Outcomes and Measures: We estimated correlations between time courses of brain networks extracted using a data-driven method (independent component analysis). Subsequently, we associated estimates of interaction strength between networks with age and autistic traits indexed by the Social Responsiveness Scale. Results: Relative to typically developing control participants, individuals with ASD showed increased functional connectivity between primary sensory networks and subcortical networks (thalamus and basal ganglia) (all t >/= 3.13, P < .001 corrected). The strength of such connections was associated with the severity of autistic traits in the ASD group (all r >/= 0.21, P < .0067 corrected). In addition, subcortico-cortical interaction decreased with age in the entire sample (all r </= -0.09, P < .012 corrected), although this association was significant only in typically developing participants (all r </= -0.13, P < .009 corrected). Conclusions and Relevance: Our results showing ASD-related impairment in the interaction between primary sensory cortices and subcortical regions suggest that the sensory processes they subserve abnormally influence brain information processing in individuals with ASD. This might contribute to the occurrence of hyposensitivity or hypersensitivity and of difficulties in top-down regulation of behavior.

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5. Dajani DR, Uddin LQ. {{Local brain connectivity across development in autism spectrum disorder: A cross-sectional investigation}}. {Autism Res};2015 (Jun 8)
There is a general consensus that autism spectrum disorder (ASD) is accompanied by alterations in brain connectivity. Much of the neuroimaging work has focused on assessing long-range connectivity disruptions in ASD. However, evidence from both animal models and postmortem examination of the human brain suggests that local connections may also be disrupted in individuals with the disorder. Here, we investigated how regional homogeneity (ReHo), a measure of similarity of a voxel’s timeseries to its nearest neighbors, varies across age in individuals with ASD and typically developing (TD) individuals using a cross-sectional design. Resting-state fMRI data obtained from a publicly available database were analyzed to determine group differences in ReHo between three age cohorts: children, adolescents, and adults. In typical development, ReHo across the entire brain was higher in children than in adolescents and adults. In contrast, children with ASD exhibited marginally lower ReHo than TD children, while adolescents and adults with ASD exhibited similar levels of local connectivity as age-matched neurotypical individuals. During all developmental stages, individuals with ASD exhibited lower local connectivity in sensory processing brain regions and higher local connectivity in complex information processing regions. Further, higher local connectivity in ASD corresponded to more severe ASD symptomatology. These results demonstrate that local connectivity is disrupted in ASD across development, with the most pronounced differences occurring in childhood. Developmental changes in ReHo do not mirror findings from fMRI studies of long-range connectivity in ASD, pointing to a need for more nuanced accounts of brain connectivity alterations in the disorder. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.

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6. de Vaan G, Vervloed M, Peters-Scheffer NC, van Gent T, Knoors H, Verhoeven L. {{Behavioural assessment of autism spectrum disorders in people with multiple disabilities}}. {J Intellect Disabil Res};2015 (Jun 8)
BACKGROUND: It is difficult to diagnose autism spectrum disorder (ASD) in people with a combination of intellectual and sensory disabilities because of overlap in behaviour. The ASD typical behaviours of people with combined intellectual and sensory disabilities are often caused by their disabilities and not by ASD. Current diagnostic tools are inadequate to differentiate between people with and without ASD when they have these combined disabilities, because tools lack norms for this population or are subjective, indirect or unable to adapt to the variety of disabilities that these people may have. Because giving a correct diagnosis is necessary for treatment and support, a new observational tool was developed to diagnose ASD in people with multiple disabilities, observation of autism in people with sensory and intellectual disabilities (OASID). METHOD: Observation of autism in people with sensory and intellectual disabilities was tested on 18 participants with moderate to profound intellectual disabilities, one or dual sensory impairment, with and without ASD. Two independent experts diagnosed these participants as well in order to test the psychometric properties and differentiating abilities of OASID. RESULTS: Observation of autism in people with sensory and intellectual disabilities showed high inter-rater reliability, internal consistency of scales and content and construct validity. OASID could differentiate people with and without ASD without overlap. CONCLUSIONS: Observation of autism in people with sensory and intellectual disabilities could differentiate people with intellectual disabilities combined with sensory impairments, who clearly had or did not have signs of ASD. People with unclear signs of ADS scored in between those two groups with regard to their OASID scores. Psychometric properties of OASID are promising.

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7. Deutsch SI, Burket JA, Urbano MR, Benson AD. {{The alpha Nicotinic Acetylcholine Receptor: a Mediator of Pathogenesis and Therapeutic Target in Autism Spectrum Disorders and Down Syndrome}}. {Biochem Pharmacol};2015 (Jun 11)
Currently, there are no medications that target core deficits of social communication and restrictive, repetitive patterns of behavior in persons with autism spectrum disorders (ASDs). Adults with Down syndrome (DS) display a progressive worsening of adaptive functioning, which is associated with Alzheimer’s disease (AD)-like histopathological changes in brain. Similar to persons with ASDs, there are no effective medication strategies to prevent or retard the progressive worsening of adaptive functions in adults with DS. Data suggest that the alpha7-subunit containing nicotinic acetylcholine receptor (alpha7nAChR) is implicated in the pathophysiology and serves as a promising therapeutic target of these disorders. In DS, production of the amyloidogenic Abeta1-42 peptide is increased and binds to the alpha7nAChR or the lipid milieu associated with this receptor, causing a cascade that results in cytotoxicity and deposition of amyloid plaques. Independently of their ability to inhibit the complexing of Abeta1-42 with the alpha7nAChR, alpha7nAChR agonists and positive allosteric modulators (PAMs) also possess procognitive and neuroprotective effects in relevant invivo and invitro models. The procognitive and neuroprotective effects of alpha7nAChR agonist interventions may be due, at least in part, to stimulation of the PI3K/Akt signaling cascade, cross-talk with the Wnt/beta-catenin signaling cascade and both transcriptional and non-transcriptional effects of beta-catenin, and effects of transiently increased intraneuronal concentrations of Ca2+ on metabolism and the membrane potential. Importantly, alpha7nAChR PAMs are particularly attractive medication candidates because they lack intrinsic efficacy and act only when and where endogenous acetylcholine is released or choline is generated.

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8. English MC, Maybery MT, Visser TA. {{Individuals with Autistic-Like Traits Show Reduced Lateralization on a Greyscales Task}}. {J Autism Dev Disord};2015 (Jun 10)
Individuals with autism spectrum conditions attend less to the left side of centrally presented face stimuli compared to neurotypical individuals, suggesting a reduction in right hemisphere activation. We examined whether a similar bias exists for non-facial stimuli in a large sample of neurotypical adults rated above- or below-average on the autism spectrum quotient (AQ). Using the « greyscales » task, we found the typical leftward bias in the below-average group was significantly reduced in the above-average group. Moreover, a negative correlation between leftward bias and the social skills factor of the AQ suggested a link between atypical hemispheric activation and social difficulties in high-AQ trait individuals that extends to non-facial stimuli.

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9. Green SA, Hernandez L, Tottenham N, Krasileva K, Bookheimer SY, Dapretto M. {{Neurobiology of Sensory Overresponsivity in Youth With Autism Spectrum Disorders}}. {JAMA Psychiatry};2015 (Jun 10)
Importance: More than half of youth with autism spectrum disorders (ASDs) have sensory overresponsivity (SOR), an extreme negative reaction to sensory stimuli. However, little is known about the neurobiological basis of SOR, and there are few effective treatments. Understanding whether SOR is due to an initial heightened sensory response or to deficits in regulating emotional reactions to stimuli has important implications for intervention. Objective: To determine differences in brain responses, habituation, and connectivity during exposure to mildly aversive sensory stimuli in youth with ASDs and SOR compared with youth with ASDs without SOR and compared with typically developing control subjects. Design, Setting, and Participants: Functional magnetic resonance imaging was used to examine brain responses and habituation to mildly aversive auditory and tactile stimuli in 19 high-functioning youths with ASDs and 19 age- and IQ-matched, typically developing youths (age range, 9-17 years). Brain activity was related to parents’ ratings of children’s SOR symptoms. Functional connectivity between the amygdala and orbitofrontal cortex was compared between ASDs subgroups with and without SOR and typically developing controls without SOR. The study dates were March 2012 through February 2014. Main Outcomes and Measures: Relative increases in blood oxygen level-dependent signal response across the whole brain and within the amygdala during exposure to sensory stimuli compared with fixation, as well as correlation between blood oxygen level-dependent signal change in the amygdala and orbitofrontal cortex. Results: The mean age in both groups was 14 years and the majority in both groups (16 of 19 each) were male. Compared with neurotypical control participants, participants with ASDs displayed stronger activation in primary sensory cortices and the amygdala (P < .05, corrected). This activity was positively correlated with SOR symptoms after controlling for anxiety. The ASDs with SOR subgroup had decreased neural habituation to stimuli in sensory cortices and the amygdala compared with groups without SOR. Youth with ASDs without SOR showed a pattern of amygdala downregulation, with negative connectivity between the amygdala and orbitofrontal cortex (thresholded at z > 1.70, P < .05). Conclusions and Relevance: Results demonstrate that youth with ASDs and SOR show sensorilimbic hyperresponsivity to mildly aversive tactile and auditory stimuli, particularly to multiple modalities presented simultaneously, and show that this hyperresponsivity is due to failure to habituate. In addition, findings suggest that a subset of youth with ASDs can regulate their responses through prefrontal downregulation of amygdala activity. Implications for intervention include minimizing exposure to multiple sensory modalities and building coping strategies for regulating emotional response to stimuli.

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10. Huang F, Long Z, Chen Z, Li J, Hu Z, Qiu R, Zhuang W, Tang B, Xia K, Jiang H. {{Investigation of Gene Regulatory Networks Associated with Autism Spectrum Disorder Based on MiRNA Expression in China}}. {PLoS One};2015;10(6):e0129052.

Autism spectrum disorder (ASD) comprise a group of neurodevelopmental disorders characterized by deficits in social and communication capacities and repetitive behaviors. Increasing neuroscientific evidence indicates that the neuropathology of ASD is widespread and involves epigenetic regulation in the brain. Differentially expressed miRNAs in the peripheral blood from autism patients were identified by high-throughput miRNA microarray analyses. Five of these miRNAs were confirmed through quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis. A search for candidate target genes of the five confirmed miRNAs was performed through a Kyoto encyclopedia of genes and genomes (KEGG) biological pathways and Gene Ontology enrichment analysis of gene function to identify gene regulatory networks. To the best of our knowledge, this study provides the first global miRNA expression profile of ASD in China. The differentially expressed miR-34b may potentially explain the higher percentage of male ASD patients, and the aberrantly expressed miR-103a-3p may contribute to the abnormal ubiquitin-mediated proteolysis observed in ASD.

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11. Kramer JM, Liljenquist K, Ni P, Coster WJ. {{Examining differential responses of youth with and without autism on a measure of everyday activity performance}}. {Qual Life Res};2015 (Jun 11)
PURPOSE: This study further investigated items with differential item function (DIF) in the Social/Cognitive domain of a measure of everyday activity performance, the Pediatric Evaluation of Disability Inventory-Computer Adapted Test version for Autism « PEDI-CAT (ASD), » to understand possible sources of response variation in a heterogeneous sample of youth with autism compared to the national standardization sample. METHODS: Cross-sectional design. A convenience sample of parents who identified they had a child between 3 and 21 years (M = 11.9 years, SD = 4.67 years) with autism (n = 365) completed an online survey that included the PEDI-CAT (ASD) and descriptive measures. For 28 items previously identified as having DIF, the PEDI-CAT (ASD) expected item score curves for the autism sample were compared to the original PEDI-CAT standardization sample. The weighted area between expected score curves (wABC) was also calculated; values >0.24 indicate significant DIF. RESULTS: All items had wABC that exceeded the criterion. Compared with peers without disabilities at the same ability level, 11 items were significantly more difficult for the youth with autism and 16 items were significantly easier. One item demonstrated non-uniform DIF. CONCLUSION: Differential responses could indicate that: (1) children with autism have a different developmental pattern of skill acquisition for everyday activities in the Social/Cognitive domain, or (2) parents of children with autism utilize a unique appraisal process when assessing their children’s functional performance of everyday activities. Further research is required to better understand the factors leading to differential responses on the targeted items. The study illustrates the value of in-depth analysis of DIF to gain insight into the impact of a clinical condition on functional performance.

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12. Masuya Y, Okamoto Y, Inohara K, Matsumura Y, Fujioka T, Wada Y, Kosaka H. {{Sex-different abnormalities in the right second to fourth digit ratio in Japanese individuals with autism spectrum disorders}}. {Mol Autism};2015;6:34.

BACKGROUND: The prevalence of autism spectrum disorders (ASDs) is higher in men than in women. The extreme male brain theory proposes that excessive prenatal testosterone activity could be a risk factor for ASDs. However, it is unclear whether prenatal sex hormone activity is a risk factor for women. The ratio of the length of the second to fourth digits (2D:4D) is considered to be a biomarker of the prenatal ratio of testosterone to estrogen. Therefore, this study compared the 2D:4D ratios of women with and without ASDs to determine if prenatal sex hormone activity could be a risk factor for ASDs in women. METHODS: The study included 35 Japanese men with ASDs, 17 Japanese women with ASDs, 59 typically developed (TD) Japanese men, and 57 TD Japanese women. We measured digit lengths and compared the 2D:4D ratios among the four groups. We also examined the relationship between the 2D:4D ratio and the autism-spectrum quotient score of each group. RESULTS: In our cohort, men with ASDs tended to have lower right-hand 2D:4D ratios relative to TD men. In contrast, the right 2D:4D ratios in women with ASDs were higher compared to those of TD women. No significant correlations were found between the 2D:4D ratios and the autism-spectrum quotient scores in any group. The higher right 2D:4D ratios in women could not be explained by age or full-scale intelligent quotients. This group difference was not found for the left 2D:4D or right-left 2D:4D ratios. CONCLUSIONS: We found a reverse direction of abnormality in the right 2D:4D ratio for men and women with ASDs. It has been posited that high prenatal testosterone levels lead to a lower 2D:4D ratio. However, a recent animal study showed that testosterone injection to dam leads to a higher right 2D:4D ratio especially for female offspring, which might be mediated by abnormal adipose accumulation in the fingertip. Therefore, the present findings suggest that high prenatal testosterone could be a risk factor both for Japanese men and women with ASDs, elucidating one potential etiology of ASDs in women.

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13. Murdaugh DL, Maximo JO, Kana RK. {{Changes in intrinsic connectivity of the brain’s reading network following intervention in children with autism}}. {Hum Brain Mapp};2015 (Jun 9)
While task-based neuroimaging studies have identified alterations in neural circuitry underlying language processing in children with autism spectrum disorders [ASD], resting state functional magnetic resonance imaging [rsfMRI] is a promising alternative to the constraints posed by task-based fMRI. This study used rsfMRI, in a longitudinal design, to study the impact of a reading intervention on connectivity of the brain regions involved in reading comprehension in children with ASD. Functional connectivity was examined using group independent component analysis (GICA) and seed-based correlation analysis of Broca’s and Wernicke’s areas, in three groups of participants: an experimental group of ASD children (ASD-EXP), a wait list control group of ASD children (ASD-WLC), and a group of typically developing (TD) control children. Both GICA and seed-based analyses revealed stronger functional connectivity of Broca’s and Wernicke’s areas in the ASD-EXP group postintervention. Additionally, improvement in reading comprehension in the ASD-EXP group was correlated with greater connectivity in both Broca’s and Wernicke’s area in the GICA identified reading network component. In addition, increased connectivity between the Broca’s area and right postcentral and right STG, and the Wernicke’s area and LIFG, were also correlated with greater improvement in reading comprehension. Overall, this study revealed widespread changes in functional connectivity of the brain’s reading network as a result of intervention in children with ASD. These novel findings provide valuable insights into the neuroplasticity of brain areas underlying reading and the impact of intensive intervention in modifying them in children with ASD. Hum Brain Mapp, 2015. (c) 2015 Wiley Periodicals, Inc.

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14. Pohodich AE, Zoghbi HY. {{Rett syndrome: disruption of epigenetic control of postnatal neurological functions}}. {Hum Mol Genet};2015 (Jun 9)
Loss of function mutations in the X-linked gene Methyl-CpG-binding protein 2 (MECP2) cause a devastating pediatric neurological disorder called Rett syndrome. In males, these mutations typically result in severe neonatal encephalopathy and early lethality. On the other hand, owing to expression of the normal allele in approximately 50% of cells, females do not suffer encephalopathy but instead develop Rett syndrome. Typically females with Rett syndrome exhibit a delayed onset of neurologic dysfunction that manifests around the child’s first birthday and progresses over the next few years. Features of this disorder include loss of acquired language and motor skills, intellectual impairment, and hand stereotypies. The developmental regression observed in patients with Rett syndrome arises from altered neuronal function and is not the result of neurodegeneration. Maintenance of an appropriate level of MeCP2 appears integral to the function of healthy neurons as patients with increased levels of MeCP2, due to duplication of the Xq28 region encompassing the MECP2 locus, also present with intellectual disability and progressive neurologic symptoms. Despite major efforts over the past two decades to elucidate the molecular functions of MeCP2, the mechanisms underlying the delayed appearance of symptoms remain unclear. In this review, we will highlight recent findings that have expanded our knowledge of MeCP2’s functions, and we will discuss how epigenetic regulation, chromatin organization, and circuit dynamics may contribute to the postnatal onset of Rett syndrome.

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15. Poole D, Gowen E, Warren PA, Poliakoff E. {{Investigating Visual-Tactile Interactions over Time and Space in Adults with Autism}}. {J Autism Dev Disord};2015 (Jun 11)
It has been suggested that the sensory symptoms which affect many people with autism spectrum conditions (ASC) may be related to alterations in multisensory processing. Typically, the likelihood of interactions between the senses increases when information is temporally and spatially coincident. We explored visual-tactile interactions in adults with ASC for the first time in two experiments using low-level stimuli. Both participants with ASC and matched neurotypical controls only produced crossmodal interactions to near simultaneous stimuli, suggesting that temporal modulation is unaffected in the adult population. We also provide preliminary evidence that visual-tactile interactions may occur over greater spatial distances in participants with ASC, which merits further exploration.

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16. Sabers A, Bertelsen FC, Scheel-Kruger J, Nyengaard JR, Moller A. {{Corrigendum to « Long-term valproic acid exposure increases the number of neocortical neurons in the developing rat brain » [Neurosci.Lett. 580 (2014) 12-16] A possible new animal model of autism}}. {Neurosci Lett};2015 (Feb 19);588:203-207.

The aim of this study was to test the hypothesis that long-term fetal valproic acid (VPA) exposure at doses relevant to the human clinic interferes with normal brain development. Pregnant rats were given intraperitoneal injections of VPA (20 mg/kg or 100 mg/kg) continuously during the last 9-12 days of pregnancy and during the lactation period until sacrifice on the 23rd postnatal day. Total number of neocortical neurons was estimated using the optical fraction at or and frontal cortical thicknesses were sampled in VPA exposed pups compared with an unexposed control group. We found that pups exposed to 20 mg/kg and 100 mg/kg doses of VPA had statistically significant higher total number of neurons in neocortex by 15.8% and 12.3%, respectively, (p < 0.05) compared to controls amounting to 15.5??106 neocortical neurons (p < 0.01). There was no statistical difference between the two VPA groups. Pups exposed to 100 mg/kg, but not to 20 mg/kg VPA displayed a significant (p < 0.05) broader (7.5%) of frontal cortical thickness compared to controls. Our results support the hypothesis that fetal exposure of VPA may interfere with normal brain development by disturbing neocortical organization, resulting in overgrowth of frontal lobes and increased neuronal cell numbers. The results indirectly suggest that prenatal VPA may contribute as a causative factor in the brain developmental disturbances equivalent to those seen inhuman autism spectrum disorders. We therefore suggest that this version of the VPA model may provide a translational model of autism.

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17. Schmidt RJ, Hansen RL, Hartiala J, Allayee H, Sconberg JL, Schmidt LC, Volk HE, Tassone F. {{Selected vitamin D metabolic gene variants and risk for autism spectrum disorder in the CHARGE Study}}. {Early Hum Dev};2015 (Jun 11);91(8):483-489.

BACKGROUND: Vitamin D is essential for proper neurodevelopment and cognitive and behavioral function. We examined associations between autism spectrum disorder (ASD) and common, functional polymorphisms in vitamin D pathways. METHODS: Children aged 24-60months enrolled from 2003 to 2009 in the population-based CHARGE case-control study were evaluated clinically and confirmed to have ASD (n=474) or typical development (TD, n=281). Maternal, paternal, and child DNA samples for 384 (81%) families of children with ASD and 234 (83%) families of TD children were genotyped for: TaqI, BsmI, FokI, and Cdx2 in the vitamin D receptor (VDR) gene, and CYP27B1 rs4646536, GC rs4588, and CYP2R1 rs10741657. Case-control logistic regression, family-based log-linear, and hybrid log-linear analyses were conducted to produce risk estimates and 95% confidence intervals (CI) for each allelic variant. RESULTS: Paternal VDR TaqI homozygous variant genotype was significantly associated with ASD in case-control analysis (odds ratio [OR] [CI]: 6.3 [1.9-20.7]) and there was a trend towards increased risk associated with VDR BsmI (OR [CI]: 4.7 [1.6-13.4]). Log-linear triad analyses detected parental imprinting, with greater effects of paternally-derived VDR alleles. Child GC AA-genotype/A-allele was associated with ASD in log-linear and ETDT analyses. A significant association between decreased ASD risk and child CYP2R1 AA-genotype was found in hybrid log-linear analysis. There were limitations of low statistical power for less common alleles due to missing paternal genotypes. CONCLUSIONS: This study provides preliminary evidence that paternal and child vitamin D metabolism could play a role in the etiology of ASD; further research in larger study populations is warranted.

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18. Sung C, Sanchez J, Kuo HJ, Wang CC, Leahy MJ. {{Gender Differences in Vocational Rehabilitation Service Predictors of Successful Competitive Employment for Transition-Aged Individuals with Autism}}. {J Autism Dev Disord};2015 (Jun 10)
As males and females with autism spectrum disorder (ASD) experience different symptomology, their needs for vocational rehabilitation (VR) are unique as they transition into adulthood. This study examined the effects of gender differences in VR service predictors on employment outcomes for transition-aged individuals with ASD. A total of 1696 individuals (857 males and 839 females) were analyzed from a sample of RSA-911 data of FY 2011. Hierarchical logistic regression analyses were conducted. Results revealed both gender-independent VR service predictors (with job placement and on-the-job supports more beneficial for both genders) and gender-specific predictors of employment (with counseling and guidance, job search assistance, and other services more beneficial for the male group). This study provides support for individualized gender-specific VR services for people with ASD.

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19. Whitaker L, Jones CR, Wilkins AJ, Roberson D. {{Judging the Intensity of Emotional Expression in Faces: the Effects of Colored Tints on Individuals With Autism Spectrum Disorder}}. {Autism Res};2015 (Jun 8)
Individuals with autism spectrum disorder (ASD) often show atypical processing of facial expressions, which may result from visual stress. In the current study, children with ASD and matched controls judged which member of a pair of faces displayed the more intense emotion. Both faces showed anger, disgust, fear, happiness, sadness or surprise but to different degrees. Faces were presented on a monitor that was tinted either gray or with a color previously selected by the participant individually as improving the clarity of text. Judgments of emotional intensity improved significantly with the addition of the preferred colored tint in the ASD group but not in controls, a result consistent with a link between visual stress and impairments in processing facial expressions in individuals with ASD. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.

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