Pubmed du 29/11/12

Pubmed du jour

2012-11-29 12:03:50

1. Adams JB, Audhya T, McDonough-Means S, Rubin RA, Quig D, Geis E, Gehn E, Loresto M, Mitchell J, Atwood S, Barnhouse S, Lee W. {{Toxicological Status of Children with Autism vs. Neurotypical Children and the Association with Autism Severity}}. {Biol Trace Elem Res};2012 (Nov 29)

This study investigates both the level of toxic metals in children with autism and the possible association of those toxic metals with autism severity. This study involved 55 children with autism ages 5-16 years compared to 44 controls with similar age and gender. The study included measurements of toxic metals in whole blood, red blood cells (RBC), and urine. The autism group had higher levels of lead in RBC (+41 %, p = 0.002) and higher urinary levels of lead (+74 %, p = 0.02), thallium (+77 %, p = 0.0001), tin (+115 %, p = 0.01), and tungsten (+44 %, p = 0.00005). However, the autism group had slightly lower levels of cadmium in whole blood (-19 %, p = 0.003). A stepwise, multiple linear regression analysis found a strong association of levels of toxic metals with variation in the degree of severity of autism for all the severity scales (adjusted R (2) of 0.38-0.47, p < 0.0003). Cadmium (whole blood) and mercury (whole blood and RBC) were the most consistently significant variables. Overall, children with autism have higher average levels of several toxic metals, and levels of several toxic metals are strongly associated with variations in the severity of autism for all three of the autism severity scales investigated.

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2. Al-Farsi YM, Waly MI, Al-Sharbati MM, Al-Shafaee MA, Al-Farsi OA, Al-Khaduri MM, Gupta I, Ouhtit A, Al-Adawi S, Al-Said MF, Deth RC. {{Levels of Heavy Metals and Essential Minerals in Hair Samples of Children with Autism in Oman: a Case-Control Study}}. {Biol Trace Elem Res};2012 (Nov 28)

Toxic levels of heavy metals and low levels of essential minerals have been suggested to play a critical role in the pathogenesis of autism spectrum disorders (ASD). This study documents the levels of heavy metals and essential minerals in hair samples of children with ASD in Muscat, the urbanized capital of Oman, Muscat. The study included 27 children with ASD and 27 matched non-ASD controls. Parental interviews were held and dietary intake questionnaires completed in conjunction with the collection of hair samples. Analysis of heavy metals and essential minerals was carried out by inductively coupled plasma mass spectrometry. Chi-square analysis and non-parametric Fisher’s exact tests were used to assess statistical significance. Children with ASD had significantly higher levels of all 11 analyzed heavy metals in their hair samples (P < 0.05), ranging from 150 to 365 % of control levels. ASD children also had significantly higher levels of essential minerals sulfur, sodium, magnesium, potassium, zinc, and iron, but lower levels of calcium and copper in their hair samples. This study corroborates data from previous studies in different parts of the world indicating the presence of elevated levels of heavy metals and selective depletion of essential minerals in the hair of children with ASD.

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3. Becchio C, Castiello U. {{Visuomotor resonance in autism spectrum disorders}}. {Front Integr Neurosci};2012;6:110.

When we observe the actions performed by others, our motor system « resonates » along with that of the observed agent. Is a similar visuomotor resonant response observed in autism spectrum disorders (ASD)? Studies investigating action observation in ASD have yielded inconsistent findings. In this perspective article we examine behavioral and neuroscientific evidence in favor of visuomotor resonance in ASD, and consider the possible role of action-perception coupling in social cognition. We distinguish between different aspects of visuomotor resonance and conclude that while some aspects may be preserved in ASD, abnormalities exist in the way individuals with ASD convert visual information from observed actions into a program for motor execution. Such abnormalities, we surmise, may contribute to but also depend on the difficulties that individuals with ASD encounter during social interaction.

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4. Billeci L, Calderoni S, Tosetti M, Catani M, Muratori F. {{White matter connectivity in children with autism spectrum disorders: a tract-based spatial statistics study}}. {BMC Neurol};2012 (Nov 29);12(1):148.

ABSTRACT: BACKGROUND: Autism spectrum disorders (ASD) are associated with widespread alterations in white matter (WM) integrity. However, while a growing body of studies is shedding light on microstructural WM alterations in high-functioning adolescents and adults with ASD, literature is still lacking in information about whole brain structural connectivity in children and low-functioning patients with ASD. This research aims to investigate WM connectivity in ASD children with and without mental retardation compared to typically developing controls (TD). METHODS: Diffusion tensor imaging (DTI) was performed in 22 young children with ASD (mean age: 5.54 years) and 10 controls (mean age: 5.25 years). Data were analysed both using the tract-based spatial statistics (TBSS) and the tractography. Correlations were investigated between the WM microstructure in the identified altered regions and the productive language level. RESULTS: The TBSS analysis revealed widespread increase of fractional anisotropy (FA) in major WM pathways. The tractographic approach showed an increased fiber length and FA in the cingulum and in the corpus callosum and an increased mean diffusivity in the indirect segments of the right arcuate and the left cingulum. Mean diffusivity was also correlated with expressive language functioning in the left indirect segments of the arcuate fasciculus. CONCLUSIONS: Our study confirmed the presence of several structural connectivity abnormalities in young ASD children. In particular, the TBSS profile of increased FA that characterized the ASD patients extends to children a finding previously detected in ASD toddlers only. The WM integrity abnormalities detected may be relevant to the pathophysiology of ASD, since the structures involved participate in some core atypical characteristics of the disorder.

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5. Calder L, Hill V, Pellicano E. {{‘Sometimes I want to play by myself’: Understanding what friendship means to children with autism in mainstream primary schools}}. {Autism};2012 (Nov 27)

Research has shown that friendship impacts the overall experience of mainstream school for autistic children. Using a unique combination of quantitative, qualitative and social network methods, we investigated the extent and nature of autistic children’s friendships from their perspective and from those of their mothers, teachers and classroom peers. Consistent with previous research, children with autism (n = 12), aged between 9 and 11 years, rated their friendships to be of poorer quality than their non-autistic classroom peers (n = 11). There was, however, much variability in autistic children’s ratings, which, unexpectedly, was related to neither children’s cognitive ability nor their theory of mind ability. Encouragingly, the children generally reported satisfaction with their friendships, and although no child was socially isolated, the degree of inclusion in friendship networks varied widely. Furthermore, autistic children’s social motivation emerged as a key factor in parents’ and teachers’ reports in determining both the nature and extent of their friendships. Adults played an active role in supporting children’s friendships, but this sometimes conflicted with what the children wanted. These findings highlight the need to ascertain the perspectives of young people with autism on their friendships and to consider the social and ethical implications of when and how to intervene.

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6. Canitano R. {{Novel treatments in Autism Spectrum Disorders: from synaptic dysfunction to experimental therapeutics}}. {Behav Brain Res};2012 (Nov 29)

Recent discoveries and advances in genetics and neuroscience have provided deeper understanding of the complex neurobiology of ASD. The development of novel treatments is strictly dependent on these findings in order to design new strategies in the pharmacotherapy of ASD. At this time, therapeutics are limited to treating associated core, symptoms. Studies of single gene disorders, such as Rett Syndrome, Fragile X and Tuberous Sclerosis, might be of significant help since the neurobiology of these disorders is clearer and clinical trials are already underway for these conditions. The pathogenesis paradigm shift of ASD towards synaptic abnormalities has led to current research of the pathways to disease, which involves multiple dynamic systems. Interest in Oxytocin is growing as it has been recognized to be implicated in social development and affiliative behaviours. In the future, progress is expected in possible new options for therapeutics in ASD. Children and Adolescents with ASD and their families can provide vital information about their experiences with new treatments, which should be a priority for future research.

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7. Dijk DJ. {{Sleep spindles, mobile phones, lucid dreaming and sleep in Parkinson’s disease and autism spectrum disorders}}. {J Sleep Res};2012 (Dec);21(6):601-602.

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8. Kalb LG, Stuart EA, Freedman B, Zablotsky B, Vasa R. {{Psychiatric-Related Emergency Department Visits Among Children With an Autism Spectrum Disorder}}. {Pediatr Emerg Care};2012 (Nov 26)

OBJECTIVE: This study aimed to examine the prevalence and characteristics of psychiatry-related emergency department (ED) visits among children with an autism spectrum disorder (ASD), including the specific reason for visit, as well as the influence of insurance type. METHODS: Data used for this cross-sectional, observational study were obtained from the 2008 National Emergency Department Sample, the largest all-payer ED database in the United States. Psychiatry-related visits to the ED among children with ASD were identified using International Classification of Diseases, Ninth Revision, billing codes. A total of 3,974,332 visits (unweighted) were present for youth 3-17 years, of which 13,191 involved a child with ASD. RESULTS: Thirteen percent of visits among children with ASD were due to a psychiatric problem, as compared with 2% of all visits by youths without ASD. Results from the multivariate analyses revealed that the likelihood for a psychiatric ED visit was increased 9-fold (odds ratio [OR], 9.13; 95% confidence interval [CI], 8.61-9.70) among pediatric ASD visits, compared with non-ASD visits. Children with ASD who were covered by private insurance, compared with those with medical assistance, were at even greater risk for a psychiatric ED visit (OR, 1.58; 95% CI, 1.53-1.63). Visits among children with ASD were more likely to be due to externalizing (OR, 1.62; 95% CI, 1.44-1.83) and psychotic (OR, 1.93; 95% CI, 1.58-2.35) disorders compared with visits among non-ASD children. CONCLUSIONS: This study highlights the need for improving community-based psychiatric systems of care for youths with ASD to divert psychiatry-related ED visits, particularly for those children with private insurance.

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9. Klusek J, Losh M, Martin GE. {{Sex differences and within-family associations in the broad autism phenotype}}. {Autism};2012 (Nov 27)

While there is a strong sex bias in the presentation of autism, it is unknown whether this bias is also present in subclinical manifestations of autism among relatives, or the broad autism phenotype. This study examined this question and investigated patterns of co-occurrence of broad autism phenotype traits within families of individuals with autism. Pragmatic language and personality features of the broad autism phenotype were studied in 42 fathers and 50 mothers of individuals with autism using direct assessment tools used in prior family studies of the broad autism phenotype. Higher rates of aloof personality style were detected among fathers, while no sex differences were detected for other broad autism phenotype traits. Within individuals, pragmatic language features were associated with the social personality styles of the broad autism phenotype in mothers but not in fathers. A number of broad autism phenotype features were correlated within spousal pairs. Finally, the associations were detected between paternal broad autism phenotype characteristics and the severity of children’s autism symptoms in all three domains (social, communication, and repetitive behaviors). Mother-child correlations were detected for aspects of communication only. Together, the findings suggest that most features of the broad autism phenotype express comparably in males and females and raise some specific questions about how such features might inform studies of the genetic basis of autism.

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10. Kuenssberg R, Murray AL, Booth T, McKenzie K. {{Structural validation of the abridged Autism Spectrum Quotient-Short Form in a clinical sample of people with autism spectrum disorders}}. {Autism};2012 (Nov 27)

The primary aim of this article was to provide a structural validation of the 28-item Autism Spectrum Quotient-Short Form questionnaire in a sample of adults with clinically diagnosed autism spectrum disorders (n = 148). Confirmatory factor analysis demonstrated that the proposed structure, comprising a second-order Social Skills factor subsuming first-order factors of Social Skills, Routine, Switching and Imagination, and a Numbers/Patterns factor showed good acceptable fit to the data (chi(2) = 464.27(345), p < .05; comparative fit index = .91; Tucker Lewis index = .90; root mean squared error of approximation = .048; weighted root mean square residual = 0.98). Summed mean scores for the total sample, and males and females separately, showed no significant differences to previously reported means, with the exception of Numbers/Patterns, for which the current sample reported significantly lower means in both males (t = 3.37, p < 0.001) and females (t = 2.33, p < 0.05). The results provide support for both the proposed structure of the AQ-S and the stability of total and subscale mean scores in different samples of participants with autism spectrum disorder diagnoses.

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11. McFadden KL, Hepburn S, Winterrowd E, Schmidt GL, Rojas DC. {{Abnormalities in gamma-band responses to language stimuli in first-degree relatives of children with autism spectrum disorder: an MEG study}}. {BMC Psychiatry};2012 (Nov 29);12(1):213.

ABSTRACT: BACKGROUND: Synchronous neural oscillatory activity in the gamma range (30–80 Hz) has been shown to be abnormal in individuals with autism spectrum disorders (ASD) and their first-degree relatives in response to simple auditory stimuli. Gamma-band abnormalities in ASD probands have been seen in response to language stimuli, but this has not been investigated in first-degree relatives. This is of particular interest given that language impairments are a core symptom of ASD and may be part of the broad autism phenotype (BAP) seen in relatives. METHODS: Magnetoencephalography recordings during a continuous word recognition task were obtained for 23 parents of a child with ASD (pASD) and 28 adult control participants. Total and evoked gamma-band activity, as well as inter-trial phase-locking factor (PLF), were measured in response to the task. Beta-band activity was also measured, due to its suggested role in language processing. Participants completed a series of language measures to assess the relationship between brain activity and language function, and lateralization of task-related activity was assessed. RESULTS: The pASD group showed increased evoked gamma and beta activity, while controls had decreased evoked activity. Additionally, while both groups showed a reduction in total gamma power (commonly seen in language tasks), this reduction was more prominent in the control group. The pASD group demonstrated significantly worse performance on a measure of phonology compared to controls. Significant but distinct relationships were found between gamma/beta activity and language measures within the two groups. In addition, while the overall task generally elicited left lateralized responses, pASD showed greater left lateralization than controls in some regions of interest. CONCLUSIONS: Abnormalities in oscillatory responses to language were seen in pASD that are consistent with previous findings in ASD probands. Gamma-band responses to language stimuli have not previously been assessed in first-degree relatives of ASD probands and these findings are supportive of gamma-band activity as a heritable, neurophysiological biomarker of ASD. The possible relationship seen between language function and neural activity in the current study should be investigated further to assess if oscillatory response abnormalities may contribute to behavioural manifestations of the BAP.

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12. Nahmias AS, Kase C, Mandell DS. {{Comparing cognitive outcomes among children with autism spectrum disorders receiving community-based early intervention in one of three placements}}. {Autism};2012 (Nov 27)

Little comparative research examines which community-based preschool intervention placements produce the best outcomes for which children with autism spectrum disorders. Autism-specific placements can provide intensive evidence-based care; however, inclusion settings provide interaction with typically developing peers, the importance of which is increasingly recognized. This study examined the association between early intervention placement in three settings (autism-only, mixed disability, or inclusive) and cognitive outcomes upon entry into elementary school in an urban school district for 98 preschool-aged children with autism spectrum disorders. Initial child and demographic characteristics were similar among the three placements. Controlling for initial cognitive scores and other covariates, cognitive outcomes for children in inclusive placements were better than those of children in mixed disability settings. A consistent pattern emerged that suggested the particular importance of inclusive placements for children with initially greater social impairments, greater adaptive behavior impairments, and at least a baseline level of language skills. Opportunities to interact with typically developing peers may be particularly beneficial for certain subgroups of young children with autism spectrum disorders. The results provide preliminary insight into important child characteristics to consider when parents and providers make preschool early intervention placement decisions.

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13. Porges SW, Macellaio M, Stanfill SD, McCue K, Lewis GF, Harden ER, Handelman M, Denver J, Bazhenova OV, Heilman KJ. {{Respiratory sinus arrhythmia and auditory processing in autism: Modifiable deficits of an integrated social engagement system?}}. {Int J Psychophysiol};2012 (Nov 29)

The current study evaluated processes underlying two common symptoms (i.e., state regulation problems and deficits in auditory processing) associated with a diagnosis of autism spectrum disorders. Although these symptoms have been treated in the literature as unrelated, when informed by the Polyvagal Theory, these symptoms may be viewed as the predictable consequences of depressed neural regulation of an integrated social engagement system, in which there is down regulation of neural influences to the heart (i.e., via the vagus) and to the middle ear muscles (i.e., via the facial and trigeminal cranial nerves). Respiratory sinus arrhythmia (RSA) and heart period were monitored to evaluate state regulation during a baseline and two auditory processing tasks (i.e., the SCAN tests for Filtered Words and Competing Words), which were used to evaluate auditory processing performance. Children with a diagnosis of autism spectrum disorders (ASD) were contrasted with aged matched typically developing children. The current study identified three features that distinguished the ASD group from a group of typical developing children: 1) baseline RSA, 2) direction of RSA reactivity, and 3) auditory processing performance. In the ASD group, the pattern of change in RSA during the attention demanding SCAN tests moderated the relation between performance on the Competing Words test and IQ. In addition, in a subset of ASD participants, auditory processing performance improved and RSA increased following an intervention designed to improve auditory processing.

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14. Wright SD, D’Astous V, Wright CA, Diener ML. {{Grandparents of grandchildren with autism spectrum disorders (ASD): strengthening relationships through technology activities}}. {Int J Aging Hum Dev};2012;75(2):169-184.

This study of grandparent-grandchild relationships was embedded in the context of technology workshops offered for young children on the autism spectrum. The purpose of this research was to examine the perspectives of six involved grandparents regarding their social interactions with their grandchildren in the context of this shared technology experience. Content analysis of transcribed focus group sessions with the grandparents indicated two key themes: expectations were reframed and communication bridges were built through shared interests. Grandparents perceived that their grandchildren learned technological skills, and increased their social interactions with peers, family members (parents, siblings), and grandparents themselves. The positive experience the grandparents perceived their grandchildren to have in the program gave them hope for future educational and employment opportunities for their grandchildren. The grandparents also indicated that the shared interests in the computer program facilitated communication opportunities with their grandchildren, with other grandparents of grandchildren with ASD, and with their adult sons and daughters.

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