Pubmed du 26/07/14

Pubmed du jour

2014-07-26 12:03:50

1. Benjamin DP, Mastergeorge AM, McDuffie AS, Kover ST, Hagerman RJ, Abbeduto L. {{Effects of labeling and pointing on object gaze in boys with fragile X syndrome: An eye-tracking study}}. {Res Dev Disabil};2014 (Jul 22);35(11):2658-2672.

We examined the visual processing of a social learning stimulus and the ways in which visual attention was distributed to objects as well as to the examiner’s face during word learning under conditions that varied only in the presence or absence of a label. The goal of the current study, then, was to evaluate the effects of differentially providing pointing and labeling during exposure to a novel target object in males with fragile X syndrome (FXS) (n=14, ages 4.33-10.02), autism spectrum disorder (ASD) (n=17, ages 4.04-10.4), or typical development (TD) (n=18, ages 2.05-5.33). In particular, the present study examined attention to the examiner’s face as well as target and distracter objects that were presented as video stimuli. An eye-tracker captured gaze to the video stimuli as they were shown in order to examine the way in which children with FXS, ASD, or TD distributed their gaze toward the examiner and the objects. Results indicated that no group showed increased gaze toward the target object compared to the distracter object. However, results revealed that participants with FXS showed significantly increased face gaze compared to the novel objects, whereas children with ASD and TD both showed similar amounts of relative gaze toward the face and objects. Furthermore, the act of pointing at the target object was found to increase gaze toward the target objects compared to when there was no pointing in all groups. Together, these findings suggest that social cues like those employed in a word-learning task, when presented with video, may relate to gaze in FXS in context- or task-dependent ways that are distinct from those expected during live interaction.

Lien vers le texte intégral (Open Access ou abonnement)

2. Cidav Z, Marcus SC, Mandell DS. {{Home- and community-based waivers for children with autism: effects on service use and costs}}. {Intellect Dev Disabil};2014 (Aug);52(4):239-248.

Abstract We examined (a) the associations between Medicaid home and community-based waiver participation and service use and expenditures among children with ASD; and (b) how states’ waiver spending moderates these effects. We used 2005 Medicaid claims to identify a sample of children with autism spectrum disorder (ASD). We selected two comparison groups who had no waiver participation: (a) children who were eligible for Medicaid through disability (disability group), and (b) children who had at least one inpatient/long-term care (IP/LT) episode (IP/LT group). Waiver participants were less likely to use IP/LT services and had lower associated expenditures than the disability group. As states’ waiver spending increased, waiver participants became increasingly less likely to use IP/LT services. Waiver participants had more outpatient visits and associated expenditures; this difference increased as state waiver spending increased. Compared with the IP/LT group, waiver participants had lower IP/LT expenditures, more outpatient visits, and associated expenditures. Higher state waiver generosity increased this effect on outpatient visits and expenditures.

Lien vers le texte intégral (Open Access ou abonnement)

3. Dimitriou D, Leonard HC, Karmiloff-Smith A, Johnson MH, Thomas MS. {{Atypical development of configural face recognition in children with autism, Down syndrome and Williams syndrome}}. {J Intellect Disabil Res};2014 (Jul 25)
BACKGROUND: Configural processing in face recognition is a sensitivity to the spacing between facial features. It has been argued both that its presence represents a high level of expertise in face recognition, and also that it is a developmentally vulnerable process. METHOD: We report a cross-syndrome investigation of the development of configural face recognition in school-aged children with autism, Down syndrome and Williams syndrome compared with a typically developing comparison group. Cross-sectional trajectory analyses were used to compare configural and featural face recognition utilising the ‘Jane faces’ task. Trajectories were constructed linking featural and configural performance either to chronological age or to different measures of mental age (receptive vocabulary, visuospatial construction), as well as the Benton face recognition task. RESULTS: An emergent inversion effect across age for detecting configural but not featural changes in faces was established as the marker of typical development. Children from clinical groups displayed atypical profiles that differed across all groups. CONCLUSION: We discuss the implications for the nature of face processing within the respective developmental disorders, and how the cross-sectional syndrome comparison informs the constraints that shape the typical development of face recognition.

Lien vers le texte intégral (Open Access ou abonnement)

4. Kerr C, Breheny K, Lloyd A, Brazier J, Bailey DB, Jr., Berry-Kravis E, Cohen J, Petrillo J. {{Developing a utility index for the Aberrant Behavior Checklist (ABC-C) for fragile X syndrome}}. {Qual Life Res};2014 (Jul 26)
PURPOSE: This study aimed to develop a utility index (the ABC-UI) from the Aberrant Behavior Checklist-Community (ABC-C), for use in quantifying the benefit of emerging treatments for fragile X syndrome (FXS). METHODS: The ABC-C is a proxy-completed assessment of behaviour and is a widely used measure in FXS. A subset of ABC-C items across seven dimensions was identified to include in health state descriptions. This item reduction process was based on item performance, factor analysis and Rasch analysis performed on an observational study dataset, and consultation with five clinical experts and a methodological expert. Dimensions were combined into health states using an orthogonal design and valued using time trade-off (TTO), with lead-time TTO methods used where TTO indicated a state valued as worse than dead. Preference weights were estimated using mean, individual level, ordinary least squares and random-effects maximum likelihood estimation [RE (MLE)] regression models. RESULTS: A representative sample of the UK general public (n = 349; mean age 35.8 years, 58.2 % female) each valued 12 health states. Mean observed values ranged from 0.92 to 0.16 for best to worst health states. The RE (MLE) model performed best based on number of significant coefficients and mean absolute error of 0.018. Mean utilities predicted by the model covered a similar range to that observed. CONCLUSIONS: The ABC-UI estimates a wide range of utilities from patient-level FXS ABC-C data, allowing estimation of FXS health-related quality of life impact for economic evaluation from an established FXS clinical trial instrument.

Lien vers le texte intégral (Open Access ou abonnement)

5. Lin SC, Margolis B, Yu SM, Adirim TA. {{The Role of Medical Home in Emergency Department Use for Children With Developmental Disabilities in the United States}}. {Pediatr Emerg Care};2014 (Jul 24)
OBJECTIVE: Children with developmental disabilities (DDs) have higher rates of emergency department use (EDU) than their typically developing peers do. This study sought to elucidate the relationship between EDU frequency and access to a comprehensive medical home for children with DD. METHODS: This study conducted multivariate logistic regression analysis on data from the 2005-2006 National Survey of Children with Special Health Care Needs to explore the association between EDU frequency among children with DD and medical home. RESULTS: Compared with children with DD reporting zero EDU, children with 3 or more EDU were less likely to report access to usual health care source (adjusted odds ratio [AOR], 0.63; 95% confidence interval [CI], 0.45-0.88). Moreover, children with DD who had 3 or more EDU were less likely to have clinicians who listen to parental concerns (AOR, 0.58; 95% CI, 0.45-0.76), demonstrate sensitivity toward family values and customs (AOR = 0.60, 95% CI = 0.46, 0.78), and build meaningful family partnerships (AOR, 0.69; 95% CI, 0.53-0.89). CONCLUSIONS: The study suggests that children with DD reporting 3 or more EDU per year would likely reduce their EDU by having access to usual source of primary care services and to clinicians with skills in building meaningful partnership with the parents. The inclusion of these medical home attributes in the adoption of patient-centered medical homes with the implementation of the Affordable Care Act presents a mechanism to improve care at lower cost as well as facilitate chronic disease management and coordination between emergency medicine and primary care physicians that may lead to reductions in EDU and unnecessary hospitalization.

Lien vers le texte intégral (Open Access ou abonnement)

6. Luckhardt C, Jarczok TA, Bender S. {{Elucidating the neurophysiological underpinnings of autism spectrum disorder: new developments}}. {J Neural Transm};2014 (Jul 25)
The study of neurophysiological approaches together with rare and common risk factors for Autism Spectrum Disorder (ASD) allows elucidating the specific underlying neurobiology of ASD. Whereas most neurophysiologically based research in ASD to date has focussed on case-control differences based on the DSM- or ICD-based categorical ASD diagnosis, more recent studies have aimed at studying genetically and/or neurophysiologically defined homogeneous ASD subgroups for specific neuronal biomarkers. This review addresses the neurophysiological investigation of ASD by evoked and event-related potentials, by EEG/MEG connectivity measures such as coherence, and transcranial magnetic stimulation. As an example of classical neurophysiological studies in ASD, we report event-related potential studies which have illustrated which brain areas and processing stages are affected in the visual perception of socially relevant stimuli. However, a paradigm shift has taken place in recent years focussing on how these findings can be tracked down to basic neuronal functions such as deficits in cortico-cortical connectivity and the interaction between brain areas. Disconnectivity, for example, can again be related to genetically induced shifts in the excitation/inhibition balance. Genetic causes of ASD may be grouped by their effects on the brain’s system level to identify ASD subgroups which respond differentially to therapeutic interventions.

Lien vers le texte intégral (Open Access ou abonnement)

7. Lunsky Y, Hastings RP, Hensel J, Arenovich T, Dewa CS. {{Perceptions of positive contributions and burnout in community developmental disability workers}}. {Intellect Dev Disabil};2014 (Aug);52(4):249-257.

Abstract Research on staff supporting individuals with intellectual and developmental disabilities (IDD) tends to focus on negative aspects of the work. This study expanded on previous research on the positive consequences that work in the IDD field has on staff using a brief version of the Staff Positive Contributions Questionnaire with 926 staff. Factor analysis suggested two factors: General positive contributions and Positive work motivation. Positive work motivation was associated with high levels of personal accomplishment, but shared limited variance with the other two burnout dimensions (emotional exhaustion, depersonalization). Findings lend support to the idea that we need to consider both positive and negative aspects of work life. This brief scale may be a useful index of how staff benefit from their work.

Lien vers le texte intégral (Open Access ou abonnement)

8. Mehling MH, Tasse MJ. {{Empirically Derived Model of Social Outcomes and Predictors for Adults With ASD}}. {Intellect Dev Disabil};2014 (Aug);52(4):282-295.

Abstract This study used data from the National Core Indicators (NCI) Survey to derive an empirically validated measurement model for social outcomes and associated constructs for both individuals with Autism Spectrum Disorder (ASD) and individuals with other disabilities. Items consistent with the survey structure of the NCI were selected as initial indicators of the latent constructs Social Relationships, Community Inclusion, and Opportunity for Choice in factor analyses. Results yielded a novel factor structure that is different from the original NCI survey structure. Three factors emerged as a result of these analyses: Personal Control, Social Determination, and Social Participation and Relationships. The factor structure of each of these constructs was consistent although not identical across individuals with ASD and individuals with developmental disabilities other than ASD.

Lien vers le texte intégral (Open Access ou abonnement)

9. Monteiro CB, Savelsbergh GJ, Smorenburg AR, Graciani Z, Torriani-Pasin C, de Abreu LC, Valenti VE, Kok F. {{Quantification of functional abilities in Rett syndrome: a comparison between stages III and IV}}. {Neuropsychiatr Dis Treat};2014;10:1213-1222.

We aimed to evaluate the functional abilities of persons with Rett syndrome (RTT) in stages III and IV. The group consisted of 60 females who had been diagnosed with RTT: 38 in stage III, mean age (years) of 9.14, with a standard deviation of 5.84 (minimum 2.2/maximum 26.4); and 22 in stage IV, mean age of 12.45, with a standard deviation of 6.17 (minimum 5.3/maximum 26.9). The evaluation was made using the Pediatric Evaluation of Disability Inventory, which has 197 items in the areas of self-care, mobility, and social function. The results showed that in the area of self-care, stage III and stage IV RTT persons had a level of 24.12 and 18.36 (P=0.002), respectively. In the area of mobility, stage III had 37.22 and stage IV had 14.64 (P<0.001), while in the area of social function, stage III had 17.72 and stage IV had 12.14 (P=0.016). In conclusion, although persons with stage III RTT have better functional abilities when compared with stage IV, the areas of mobility, self-care, and social function are quite affected, which shows a great functional dependency and need for help in basic activities of daily life.

Lien vers le texte intégral (Open Access ou abonnement)

10. Robertson CE, Thomas C, Kravitz DJ, Wallace GL, Baron-Cohen S, Martin A, Baker CI. {{Global motion perception deficits in autism are reflected as early as primary visual cortex}}. {Brain};2014 (Jul 23)
Individuals with autism are often characterized as ‘seeing the trees, but not the forest’-attuned to individual details in the visual world at the expense of the global percept they compose. Here, we tested the extent to which global processing deficits in autism reflect impairments in (i) primary visual processing; or (ii) decision-formation, using an archetypal example of global perception, coherent motion perception. In an event-related functional MRI experiment, 43 intelligence quotient and age-matched male participants (21 with autism, age range 15-27 years) performed a series of coherent motion perception judgements in which the amount of local motion signals available to be integrated into a global percept was varied by controlling stimulus viewing duration (0.2 or 0.6 s) and the proportion of dots moving in the correct direction (coherence: 4%, 15%, 30%, 50%, or 75%). Both typical participants and those with autism evidenced the same basic pattern of accuracy in judging the direction of motion, with performance decreasing with reduced coherence and shorter viewing durations. Critically, these effects were exaggerated in autism: despite equal performance at the long duration, performance was more strongly reduced by shortening viewing duration in autism (P < 0.015) and decreasing stimulus coherence (P < 0.008). To assess the neural correlates of these effects we focused on the responses of primary visual cortex and the middle temporal area, critical in the early visual processing of motion signals, as well as a region in the intraparietal sulcus thought to be involved in perceptual decision-making. The behavioural results were mirrored in both primary visual cortex and the middle temporal area, with a greater reduction in response at short, compared with long, viewing durations in autism compared with controls (both P < 0.018). In contrast, there was no difference between the groups in the intraparietal sulcus (P > 0.574). These findings suggest that reduced global motion perception in autism is driven by an atypical response early in visual processing and may reflect a fundamental perturbation in neural circuitry.

Lien vers le texte intégral (Open Access ou abonnement)

11. Savoy M. {{Autism: 5 misconceptions that can complicate care}}. {J Fam Pract};2014 (Jun);63(6):310-314.

Despite an increasing understanding of autism spectrum disorder, misinformation abounds. Here’s help dispelling common misconceptions.

Lien vers Pubmed

12. Taffoni F, Focaroli V, Formica D, Gugliemelli E, Keller F, Iverson JM. {{Sensor-based technology in the study of motor skills in infants at risk for ASD}}. {Proc IEEE RAS EMBS Int Conf Biomed Robot Biomechatron};2012 (Jun):1879-1883.

Motor impairments seems to play an important role in neurodevelopmental disorders such as autism spectrum disorders (ASD). Early detection of motor abnormalities during first years of life, may give important information regarding whether a child may receive a later diagnosis of Autism: for this reason an objective assessment of motor performance is crucial. While there are several technological solutions suitable to this end, they often require highly structured environments. In this work we propose the use of a magneto-inertial platform to study early motor performance between 12-36 months of age suitable to be used in non-structured environment.

Lien vers le texte intégral (Open Access ou abonnement)

13. Veatch OJ, Pendergast JS, Allen MJ, Leu RM, Johnson CH, Elsea SH, Malow BA. {{Genetic Variation in Melatonin Pathway Enzymes in Children with Autism Spectrum Disorder and Comorbid Sleep Onset Delay}}. {J Autism Dev Disord};2014 (Jul 25)
Sleep disruption is common in individuals with autism spectrum disorder (ASD). Genes whose products regulate endogenous melatonin modify sleep patterns and have been implicated in ASD. Genetic factors likely contribute to comorbid expression of sleep disorders in ASD. We studied a clinically unique ASD subgroup, consisting solely of children with comorbid expression of sleep onset delay. We evaluated variation in two melatonin pathway genes, acetylserotonin O-methyltransferase (ASMT) and cytochrome P450 1A2 (CYP1A2). We observed higher frequencies than currently reported (p < 0.04) for variants evidenced to decrease ASMT expression and related to decreased CYP1A2 enzyme activity (p </= 0.0007). We detected a relationship between genotypes in ASMT and CYP1A2 (r2 = 0.63). Our results indicate that expression of sleep onset delay relates to melatonin pathway genes.

Lien vers le texte intégral (Open Access ou abonnement)

14. Wehman P, Chan F, Ditchman N, Kang HJ. {{Effect of supported employment on vocational rehabilitation outcomes of transition-age youth with intellectual and developmental disabilities: a case control study}}. {Intellect Dev Disabil};2014 (Aug);52(4):296-310.

Abstract The purpose of this study was to examine the effect of supported employment intervention on the employment outcomes of transition-age youth with intellectual and developmental disabilities served by the public vocational rehabilitation system using a case-control study design. Data for this study were extracted from the Rehabilitation Services Administration Case Service Report (RSA-911) database for fiscal year 2009. The sample included 23,298 youth with intellectual and developmental disabilities aged between 16 and 25 years old at the time of application. The classification and regression tree (CART) method was used to estimate propensity scores and to adjust for selection bias on the basis of all prominent covariates relevant to the dependent variable (i.e., competitive employment). Results yielded six homogeneous subgroups, and receipt of supported employment was found to increase the employment rates across all of the groups. The effect of supported employment was especially strong for youth who were Social Security beneficiaries, special education students, and individuals with intellectual disabilities or autism who were high school graduates. These findings suggest that supported employment is an effective service for enhancing the vocational rehabilitation outcomes of young adults and provides valuable information for policy makers, health care providers, rehabilitation counselors, and educators.

Lien vers le texte intégral (Open Access ou abonnement)

15. Wesseling H, Guest PC, Lee CM, Wong EH, Rahmoune H, Bahn S. {{Integrative proteomic analysis of the NMDA NR1 knockdown mouse model reveals effects on central and peripheral pathways associated with schizophrenia and autism spectrum disorders}}. {Mol Autism};2014;5:38.

BACKGROUND: Over the last decade, the transgenic N-methyl-D-aspartate receptor (NMDAR) NR1-knockdown mouse (NR1(neo-/-)) has been investigated as a glutamate hypofunction model for schizophrenia. Recent research has now revealed that the model also recapitulates cognitive and negative symptoms in the continuum of other psychiatric diseases, particularly autism spectrum disorders (ASD). As previous studies have mostly focussed on behavioural readouts, a molecular characterisation of this model will help to identify novel biomarkers or potential drug targets. METHODS: Here, we have used multiplex immunoassay analyses to investigate peripheral analyte alterations in serum of NR1(neo-/-) mice, as well as a combination of shotgun label-free liquid chromatography mass spectrometry, bioinformatic pathway analyses, and a shotgun-based 40-plex selected reaction monitoring (SRM) assay to investigate altered molecular pathways in the frontal cortex and hippocampus. All findings were cross compared to identify translatable findings between the brain and periphery. RESULTS: Multiplex immunoassay profiling led to identification of 29 analytes that were significantly altered in sera of NR1(neo-/-) mice. The highest magnitude changes were found for neurotrophic factors (VEGFA, EGF, IGF-1), apolipoprotein A1, and fibrinogen. We also found decreased levels of several chemokines. Following this, LC-MS(E) profiling led to identification of 48 significantly changed proteins in the frontal cortex and 41 in the hippocampus. In particular, MARCS, the mitochondrial pyruvate kinase, and CamKII-alpha were affected. Based on the combination of protein set enrichment and bioinformatic pathway analysis, we designed orthogonal SRM-assays which validated the abnormalities of proteins involved in synaptic long-term potentiation, myelination, and the ERK-signalling pathway in both brain regions. In contrast, increased levels of proteins involved in neurotransmitter metabolism and release were found only in the frontal cortex and abnormalities of proteins involved in the purinergic system were found exclusively in the hippocampus. CONCLUSIONS: Taken together, this multi-platform profiling study has identified peripheral changes which are potentially linked to central alterations in synaptic plasticity and neuronal function associated with NMDAR-NR1 hypofunction. Therefore, the reported proteomic changes may be useful as translational biomarkers in human and rodent model drug discovery efforts.

Lien vers le texte intégral (Open Access ou abonnement)

16. Zylstra RG, Prater CD, Walthour AE, Aponte AF. {{Autism: Why the rise in rates?}}. {J Fam Pract};2014 (Jun);63(6):316-320.

Our improved understanding of the disorder and increasingly sensitive diagnostic tools are playing a role–but so are some other factors.

Lien vers Pubmed