Pubmed du 31/03/09

Pubmed du jour

2009-03-31 12:03:50

1. Ashwood P, Schauer J, Pessah IN, de Water JV. {{Preliminary evidence of the in vitro effects of BDE-47 on innate immune responses in children with autism spectrum disorders}}. {J Neuroimmunol};2009 (Mar 31);208(1-2):130-135.

Autism spectrum disorders (ASD) are complex neurodevelopmental disorders that manifest in childhood. Immune dysregulation and autoimmune reactivity may contribute to the etiology of ASD and are likely the result of both genetic and environmental susceptibilities. A common environmental contaminant, 2,2′,4,4′-tetrabrominated biphenyl (BDE-47), was tested for differential effects on the immune response of peripheral blood mononuclear cells (PBMC) isolated from children with ASD (n=19) and age-matched typically developing controls (TD, n=18). PBMC were exposed in vitro to either 100 nM or 500 nM BDE-47, before challenge with bacterial lipopolysaccharide (LPS), an innate immune activator, with resultant cytokine production measured using the Luminex multiplex platform. The cytokine responses of LPS stimulated PBMC from ASD and TD subjects diverged in the presence of 100 nM BDE. For example, cells cultured from the TD group demonstrated significantly decreased levels of the cytokines IL-12p40, GM-CSF, IL-6, TNFalpha, and the chemokines MIP-1alpha and MIP-1beta following LPS stimulation of PBMC pretreated with 100 nM BDE-47 compared with samples treated with vehicle control (p<0.05). In contrast, cells cultured from subjects with ASD demonstrated an increased IL-1beta response to LPS (p=0.033) when pretreated with 100 nM BDE-47 compared with vehicle control. Preincubation with 500 nM BDE-47 significantly increased the stimulated release of the inflammatory chemokine IL-8 (p<0.04) in cells cultured from subjects with ASD but not in cells from TD controls. These data suggest that in vitro exposure of PBMC to BDE-47 affects cell cytokine production in a pediatric population. Moreover, PBMC from the ASD subjects were differentially affected when compared with the TD controls suggesting a biological basis for altered sensitivity to BDE-47 in the ASD population.

2. Bent S, Bertoglio K, Hendren RL. {{Omega-3 Fatty Acids for Autistic Spectrum Disorder: A Systematic Review}}. {J Autism Dev Disord};2009 (Mar 31)

We conducted a systematic review to determine the safety and efficacy of omega-3 fatty acids for autistic spectrum disorder (ASD). Articles were identified by a search of MEDLINE, EMBASE, and the Cochrane Database using the terms autism or autistic and omega-3 fatty acids. The search identified 143 potential articles and six satisfied all inclusion criteria. One small randomized controlled trial (n = 13) noted non-significant improvements in hyperactivity and stereotypy. The remaining five studies were small (n = 30, 22, 19, 9, and 1) with four reporting improvements in a wide range of outcomes including language and learning skills, parental observations of general health and behavior, a clinician-administered symptom scale, and clinical observations of anxiety. Due to the limitations of evidence from uncontrolled studies and the presence of only one small randomized controlled trial, there is currently insufficient scientific evidence to determine if omega-3 fatty acids are safe or effective for ASD.

3. Gokcen S, Bora E, Erermis S, Kesikci H, Aydin C. {{Theory of mind and verbal working memory deficits in parents of autistic children}}. {Psychiatry Res};2009 (Mar 31);166(1):46-53.

The objective of this study was to investigate the potential values of executive function and social cognition deficits as endophenotypes of autism. While theory of mind (ToM) is generally accepted as a unitary concept, some have suggested that ToM may be separated into two components (mental state reasoning and decoding). In this study, both aspects of ToM and verbal working memory abilities were investigated with relatively demanding tasks. The authors used a neurocognitive battery to compare the executive function and social cognition skills of 76 parents of autistic probands with 41 parents of healthy children. Both groups were matched for IQ, age and gender. Index parents had verbal working memory deficits. They had also low performance on a mental state reasoning task. Index parents had difficulties in reasoning about others’ emotions. In contrast to findings in the control group, low performance of mental state reasoning ability was not associated with working memory deficit in index parents. Social cognition and working memory impairments may represent potential endophenotypes, related to an underlying vulnerability for autistic spectrum disorders.

4. Klin A, Lin DJ, Gorrindo P, Ramsay G, Jones W. {{Two-year-olds with autism orient to non-social contingencies rather than biological motion}}. {Nature};2009 (Mar 29)

Typically developing human infants preferentially attend to biological motion within the first days of life. This ability is highly conserved across species and is believed to be critical for filial attachment and for detection of predators. The neural underpinnings of biological motion perception are overlapping with brain regions involved in perception of basic social signals such as facial expression and gaze direction, and preferential attention to biological motion is seen as a precursor to the capacity for attributing intentions to others. However, in a serendipitous observation, we recently found that an infant with autism failed to recognize point-light displays of biological motion, but was instead highly sensitive to the presence of a non-social, physical contingency that occurred within the stimuli by chance. This observation raised the possibility that perception of biological motion may be altered in children with autism from a very early age, with cascading consequences for both social development and the lifelong impairments in social interaction that are a hallmark of autism spectrum disorders. Here we show that two-year-olds with autism fail to orient towards point-light displays of biological motion, and their viewing behaviour when watching these point-light displays can be explained instead as a response to non-social, physical contingencies-physical contingencies that are disregarded by control children. This observation has far-reaching implications for understanding the altered neurodevelopmental trajectory of brain specialization in autism.

5. Lidstone JS, Fernyhough C, Meins E, Whitehouse AJ. {{Brief Report: Inner Speech Impairment in Children with Autism is Associated with Greater Nonverbal than Verbal Skills}}. {J Autism Dev Disord};2009 (Mar 28)

We present a new analysis of Whitehouse, Maybery, and Durkin’s (2006, Experiment 3) data on inner speech in children with autism (CWA). Because inner speech development is thought to depend on linguistically mediated social interaction, we hypothesized that children with both autism and a nonverbal > verbal (NV > V) skills profile would show the greatest inner speech impairment. CWA and typically developing controls (n = 23 in each group) undertook a timed mathematical task-switching test, known to benefit from inner speech use. Participants completed the task with and without articulatory suppression (AS), which disrupts inner speech. The hypothesis was supported: AS interference varied with cognitive profile among CWA but not among controls. Only the NV > V autism group showed no AS interference, indicating an inner speech impairment.

6. Moore TR, Symons FJ. {{Adherence to Behavioral and Medical Treatment Recommendations by Parents of Children with Autism Spectrum Disorders}}. {J Autism Dev Disord};2009 (Mar 31)

The extent to which parents of children with intellectual or developmental disabilities are adherent to prescribed treatments has not been investigated. In this treatment adherence study, parents (n = 220) of children with autism spectrum disorders were surveyed regarding implementation of recommended treatments to manage problem behavior of their children living at home. Overall adherence to medical treatment recommendations was significantly greater than adherence to behavioral treatment recommendations (p < .002). Of the behavioral treatment recommendations, parents reported greater adherence to reinforcement (81.7%) than punishment (68.9%). Child diagnosis (p < .002) and the diagnosis x marital status interaction (p < .05) were significantly associated with reported adherence to behavioral and medical treatment, respectively. Results are discussed in light of the need to address adherence enhancement and measurement methods.

7. Noor A, Gianakopoulos PJ, Fernandez B, Marshall CR, Szatmari P, Roberts W, Scherer SW, Vincent JB. {{Copy number variation analysis and sequencing of the X-linked mental retardation gene TSPAN7/TM4SF2 in patients with autism spectrum disorder}}.{ Psychiatr Genet};2009 (Mar 31)

8. Sandhu B, Steer CD, Golding J, Emond AM. {{The early stool patterns of young children with autistic spectrum disorder}}. {Arch Dis Child};2009 (Mar 26)

AIM: To investigate whether children with autistic spectrum disorder (ASD) have bowel symptoms consistent with an underlying enterocolitis. METHODS: Information on children’s stool patterns and gut symptoms collected by questionnaire at 4 weeks and 6, 18, 30 and 42 months of age were available for 12984 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Data on the 78 children identified by local health and/or education systems to have special educational provision for ASD were compared with the 12906 remaining children in the cohort. RESULTS: Comparison of the ASD and control group during the first 3.5 years of life showed no major differences in stool colour or consistency, or in frequency of diarrhoea, constipation, bloody stools or abdominal pain. The ASD children had similar stool frequency up to 18 months, but there was a trend for ASD children to pass more stools at 30 months (odds ratio [OR] 3.73, 95% CI 1.11, 12.6; P = 0.004) and at 42 months (OR 6.46, 95% CI 1.83, 22.7; P<0.001), although only three children passed more than 4 stools/day. Repeating the analysis on only those cases diagnosed as having classical childhood autism resulted in very similar findings. CONCLUSIONS: During the first 42 months of life ASD children had a stool pattern that was very similar to other children, apart from a slight increase in stool frequency at 30 and 42 months. There were no symptoms to support the hypothesis that ASD children had an enterocolitis.

9. Sebastian C, Blakemore SJ, Charman T. {{Reactions to Ostracism in Adolescents with Autism Spectrum Conditions}}. {J Autism Dev Disord};2009 (Mar 28)

Little is known about how adolescents with autism spectrum conditions (ASC) experience the initial impact of ostracism. This study investigated whether a mild, short-term episode of experimentally induced ostracism (Cyberball) would affect self-reported anxiety, mood, and the extent to which four social needs (self-esteem, belonging, control and meaningful existence) were threatened in adolescents with ASC and matched controls. Anxiety and the four needs were negatively affected by ostracism in both groups. However, ostracism did not modulate mood in the ASC group, and a number of possible interpretations of this group difference are discussed. In general, the results of this study suggest that normative models of ostracism are applicable to ASC.

10. Velloso Rde L, de Araujo CA, Schwartzman JS. {{Concepts of color, shape, size and position in ten children with Rett syndrome}}. {Arq Neuropsiquiatr};2009 (Mar);67(1):50-54.

Individuals with Rett syndrome (RS) present severe motor, language and cognitive deficits, as well as spontaneous hand movement loss. On the other hand, there are strong evidence that these individuals use the eyes with intentional purpose. Ten girls aged 4y8m to 12y10m with RS were assessed with a computer system for visual tracking regarding their ability of indicating with eyes the recognition of concepts of color (red, yellow and blue), shape (circle, square and triangle), size (big and small) and spatial position (over and under) to which they were first exposed to. Results from comparing the time of eyes fixation on required and not required concepts did not differ significantly. Children did not show with eyes the recognition of the required concepts when assessed with eye tracking system.

11. Yoran-Hegesh R, Kertzman S, Vishne T, Weizman A, Kotler M. {{Neuropsychological mechanisms of Digit Symbol Substitution Test impairment in Asperger Disorder}}. {Psychiatry Res};2009 (Mar 31);166(1):35-45.

Our aim was to investigate the neurocognitive mechanisms recruited by adolescents with Asperger Disorder (AD), in comparison to controls, and to detect the underlying mechanisms during the complex information processing required for the performance of the Digit Symbol Substitution Test (DSST). Male adolescents (n=23; mean age 15.1+/-3.6 years) with a DSM-IV diagnosis of AD were compared with a normal male control group with similar demographic characteristics (n=43; mean age: 15.1+/-3.6 years). A computerized neurocognitive battery was administered and included: Inspection Time (IT), Finger Tapping Test (FTT), Simple Reaction Time (SRT), Choice Reaction Time (CRT), Digit Running task (DRT), Stroop test and Digit Symbol Substitution Test (DSST). Adolescents with AD performed significantly worse than controls on the DSST. This impaired DSST performance was related to cognitive mechanisms different from those employed by normal controls. Motor slowness and inability to deal with increased amounts of information affected the performance of the AD group, while shifting of attention was the limiting factor in the controls. Both groups were similarly dependent on response selection. This study demonstrated differences in performance in complex cognitive tasks between adolescents with AD and normal controls that may be related to differences in neurocognitive mechanisms underlying information processing. Future neuroimaging studies are needed to clarify the neural network involved in the differences in cognitive performance between AD subjects and normal controls.