Pubmed du 24/06/16

Pubmed du jour

2016-06-24 12:03:50

1. Chambers NJ, Wetherby AM, Stronach ST, Njongwe N, Kauchali S, Grinker RR. {{Early detection of autism spectrum disorder in young isiZulu-speaking children in South Africa}}. {Autism}. 2016.

Culturally appropriate tools are needed for detecting symptoms of autism spectrum disorder in young South African children. The objectives of this study were to (1) adapt and translate into isiZulu existing measures for detecting early signs of autism spectrum disorder, (2) use the measures to characterize and compare behavioural profiles of young isiZulu-speaking children with and without autism spectrum disorder and (3) compare symptom profiles across sampling procedures. Measures were translated and adapted into isiZulu and used to evaluate 26 isiZulu-speaking children, 15 children with no reported developmental concerns and 11 referred for suspected autism spectrum disorder. A video-recorded observation of children and caregivers in their home environment was also made. Based on best-estimate diagnoses, 10 children were classified as autism spectrum disorder and 16 as non-autism spectrum disorder. The children with autism spectrum disorder presented with significantly more autism spectrum disorder red flags than the non-autism spectrum disorder group according to parent report and systematic ratings of red flags. Significant correlations between parent report and observational measures of red flags were observed. More red flags were observed during structured evaluations than home observations in the autism spectrum disorder group. Findings provide a foundation for tool translation and adaptation in South Africa and identifying social communication markers to detect autism spectrum disorder in young isiZulu-speaking children.

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2. De Giacomo A, Craig F, Terenzio V, Coppola A, Campa MG, Passeri G. {{Aggressive Behaviors and Verbal Communication Skills in Autism Spectrum Disorders}}. {Glob Pediatr Health}. 2016; 3: 2333794X16644360.

Aggressive behavior is a common problem among children with autism spectrum disorder (ASD) and could negatively affect family functioning and school and social competence. The aim of the present study was to investigate the relationship between aggressive behavior, such as self-aggression and other-aggression, with verbal communication ability and IQ level in children with ASD. The sample examined in this study included 88 children with a diagnosis of ASD. For the purposes of our study, much attention was focused on individual items of the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview-Revised that were useful to evaluate the aggressive behavior. We have not found any association between aggressive behavior (other-aggression and self-aggression) and the absence of language or low IQ in children with ASD. Thus, the degree of severity of autism is probably the most important risk factor for this behavior.

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3. Doenyas C. {{The Social Living Complex: A New, All Day, Yearlong Intervention Model for Individuals with Autism Spectrum Disorder and Their Parents}}. {J Autism Dev Disord}. 2016.

We propose an unprecedented intervention for individuals with autism spectrum disorder (ASD) and their parents: the social living complex. Unlike existing social skills interventions, peer-mediated interventions here are not limited to the school/experiment duration and setting. Whereas other supported living services house adults with ASD only, here children with ASD and their families live and interact with typically developing (TD) individuals. Another novelty is support groups for parents of children with ASD, who report feeling higher levels of stress than parents of TD children and children with other disabilities, feeling isolated, and not receiving social support. This complex will enable the practice and generalization of schooled skills in the lives of children with ASD and foster an accepting, autism-friendly community.

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4. Dong T, He J, Wang S, Wang L, Cheng Y, Zhong Y. {{Inability to activate Rac1-dependent forgetting contributes to behavioral inflexibility in mutants of multiple autism-risk genes}}. {Proc Natl Acad Sci U S A}. 2016.

The etiology of autism is so complicated because it involves the effects of variants of several hundred risk genes along with the contribution of environmental factors. Therefore, it has been challenging to identify the causal paths that lead to the core autistic symptoms such as social deficit, repetitive behaviors, and behavioral inflexibility. As an alternative approach, extensive efforts have been devoted to identifying the convergence of the targets and functions of the autism-risk genes to facilitate mapping out causal paths. In this study, we used a reversal-learning task to measure behavioral flexibility in Drosophila and determined the effects of loss-of-function mutations in multiple autism-risk gene homologs in flies. Mutations of five autism-risk genes with diversified molecular functions all led to a similar phenotype of behavioral inflexibility indicated by impaired reversal-learning. These reversal-learning defects resulted from the inability to forget or rather, specifically, to activate Rac1 (Ras-related C3 botulinum toxin substrate 1)-dependent forgetting. Thus, behavior-evoked activation of Rac1-dependent forgetting has a converging function for autism-risk genes.

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5. Grainger C, Williams DM, Lind SE. {{Recognition memory and source memory in autism spectrum disorder: A study of the intention superiority and enactment effects}}. {Autism}. 2016.

It is well established that neurotypical individuals generally show better memory for actions they have performed than actions they have observed others perform or merely read about, a so-called ‘enactment effect’. Strikingly, research has also shown that neurotypical individuals demonstrate superior memory for actions they intend to perform in the future (but have not yet performed), an effect commonly known as the ‘intention superiority effect’. Although the enactment effect has been studied among people with autism spectrum disorder, this study is the first to investigate the intention superiority effect in this disorder. This is surprising given the potential importance this issue has for general theory development, as well as for clinical practice. As such, this study aimed to assess the intention superiority and enactment effects in 22 children with autism spectrum disorder, and 20 intelligence quotient/age-matched neurotypical children. The results showed that children with autism spectrum disorder demonstrated not only undiminished enactment effects in recognition and source memory, but also (surprisingly for some theories) typical intention superiority effects. The implications of these results for theory, as well as clinical practice, are discussed.

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6. Hagerman RJ, Hagerman P. {{Fragile X-associated tremor/ataxia syndrome – features, mechanisms and management}}. {Nat Rev Neurol}. 2016.

Many physicians are unaware of the many phenotypes associated with the fragile X premutation, an expansion in the 5′ untranslated region of the fragile X mental retardation 1 (FMR1) gene that consists of 55-200 CGG repeats. The most severe of these phenotypes is fragile X-associated tremor/ataxia syndrome (FXTAS), which occurs in the majority of ageing male premutation carriers but in fewer than 20% of ageing women with the premutation. The prevalence of the premutation is 1 in 150-300 females, and 1 in 400-850 males, so physicians are likely to see people affected by FXTAS. Fragile X DNA testing is broadly available in the Western world. The clinical phenotype of FXTAS at presentation can vary and includes intention tremor, cerebellar ataxia, neuropathic pain, memory and/or executive function deficits, parkinsonian features, and psychological disorders, such as depression, anxiety and/or apathy. FXTAS causes brain atrophy and white matter disease, usually in the middle cerebellar peduncles, the periventricular area, and the splenium and/or genu of the corpus callosum. Here, we review the complexities involved in the clinical management of FXTAS and consider how targeted treatment for these clinical features of FXTAS will result from advances in our understanding of the molecular mechanisms that underlie this neurodegenerative disorder. Such targeted approaches should also be more broadly applicable to earlier forms of clinical involvement among premutation carriers.

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7. Hartley SL, Papp LM, Blumenstock SM, Floyd F, Goetz GL. {{The Effect of Daily Challenges in Children With Autism on Parents’ Couple Problem-Solving Interactions}}. {J Fam Psychol}. 2016.

The vulnerability-stress-adaptation model guided this examination of the impact of daily fluctuations in the symptoms and co-occurring behavior problems of children with autism spectrum disorder (ASD) on parents’ couple problem-solving interactions in natural settings and as these interactions spontaneously occur. A 14-day daily diary was completed by mothers and fathers in 176 families who had a child with ASD. On each day of the diary, parents separately reported on the child with ASD’s daily level of symptoms and co-occurring behavior problems and the topic and level of negative affect in their most meaningful or important daily couple problem-solving interaction. Multilevel modeling was used to account for the within-person, within-couple nested structure of the data. Results indicated that many parents are resilient to experiencing a day with a high level of child ASD symptoms and co-occurring behavior problems and do not report more negative couple problem-solving interactions. However, household income, level of parental broader autism phenotype, and presence of multiple children with special care needs served as vulnerability factors in that they were related to a higher overall rating of negative affect in couple interactions and moderated the impact of reporting a day with a high level of child ASD symptoms and co-occurring behavior problems on next-day ratings of negative couple problem-solving interactions. The magnitude of these effects was small. Understanding mechanisms that support adaptive couple interactions in parents of children with ASD is critical for promoting best outcomes. (PsycINFO Database Record

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8. Lozano R, Saito N, Reed D, Eldeeb M, Schneider A, Hessl D, Tassone F, Beckett L, Hagerman R. {{Aging in Fragile X Premutation Carriers}}. {Cerebellum}. 2016.

It is now recognized that FMR1 premutation carriers (PC) are at risk to develop a range of neurological, psychiatric, and immune-mediated disorders during adulthood. There are conflicting findings regarding the incidence of hypertension, hypothyroidism, diabetes, and cancer in these patients that warrant further study. A retrospective controlled study was performed in a convenience sample of 248 controls (130 men, 118 women) and 397 FMR1 PC with and without fragile X-associated tremor ataxia syndrome (FXTAS) (176 men, 221 women); all participants were at least 45 years old (men: mean 62.4, SD 9.5; women: mean 62.8, SD 9.9; p = 0.63). Memory and cognitive assessments (Wechsler Adult Intelligence Scale (WAIS-III), Wechsler Memory Scale (WMS-III)) and molecular testing (CGG repeats and FMR1-mRNA levels) were performed. Additional data included body mass index (BMI), cholesterol levels, blood pressure, hemoglobin A1c (HbA1c) levels, and medical history. A higher percentage of PC subjects self-reported having a diagnosis of hypertension (50.0 vs. 35.0 %, p = 0.006) and thyroid problems (20.4 vs. 10.0 %, p = 0.012) than control subjects. When comparing controls versus PC with FXTAS, the association was higher for diabetes (p = 0.043); however, the effect was not significant after adjusting for demographic predictors. Blood pressure, blood glucose levels, HbA1c, and BMI values were not significantly different between the two groups. The PC with FXTAS group performed consistently lower in neuropsychological testing compared with the PC without FXTAS group, but the differences were very small for all but the WAIS full-scale IQ. Based on these findings, it appears that the risk for hypertension, thyroid problems, and diabetes may be more frequent in PC with FXTAS, which will require verification in future studies.

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9. Mazahery H, Conlon C, Beck KL, Kruger MC, Stonehouse W, Camargo CA, Jr., Meyer BJ, Tsang B, Mugridge O, von Hurst PR. {{Vitamin D and omega-3 fatty acid supplements in children with autism spectrum disorder: a study protocol for a factorial randomised, double-blind, placebo-controlled trial}}. {Trials}. 2016; 17(1): 295.

BACKGROUND: There is strong mechanistic evidence to suggest that vitamin D and omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFAs), specifically docosahexaenoic acid (DHA), have the potential to significantly improve the symptoms of autism spectrum disorder (ASD). However, there are no trials that have measured the effect of both vitamin D and n-3 LCPUFA supplementation on autism severity symptoms. The objective of this 2 x 2 factorial trial is to investigate the effect of vitamin D, n-3 LCPUFAs or a combination of both on core symptoms of ASD. METHODS/DESIGN: Children with ASD living in New Zealand (n = 168 children) will be randomised to one of four treatments daily: vitamin D (2000 IU), n-3 LCPUFAs (722 mg DHA), vitamin D (2000 IU) + n-3 LCPUFAs (722 mg DHA) or placebo for 12 months. All researchers, participants and their caregivers will be blinded until the data analysis is completed, and randomisation of the active/placebo capsules and allocation will be fully concealed from all mentioned parties. The primary outcome measures are the change in social-communicative functioning, sensory processing issues and problem behaviours between baseline and 12 months. A secondary outcome measure is the effect on gastrointestinal symptoms. Baseline data will be used to assess and correct basic nutritional deficiencies prior to treatment allocation. For safety measures, serum 25-hydroxyvitamin D 25(OH)D and calcium will be monitored at baseline, 6 and 12 months, and weekly compliance and gastrointestinal symptom diaries will be completed by caregivers throughout the study period. DISCUSSION: To our knowledge there are no randomised controlled trials assessing the effects of both vitamin D and DHA supplementation on core symptoms of ASD. If it is shown that either vitamin D, DHA or both are effective, the trial would reveal a non-invasive approach to managing ASD symptoms. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry, ACTRN12615000144516 . Registered on 16 February 2015.

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10. Nelson AT, Lopata C, Volker MA, Thomeer ML, Toomey JA, Dua E. {{Exploratory Factor Analysis of SRS-2 Teacher Ratings for Youth with ASD}}. {J Autism Dev Disord}. 2016.

This study examined the factor structure and internal consistency of special education teaching staff ratings on the Social Responsiveness Scale-2 (SRS-2; Constantino and Gruber 2012), as well as the percentage of ratings falling above pre-established cut scores, for a sample of lower-functioning youth with autism spectrum disorder (ASD; n = 264). Results of the exploratory factor analysis yielded a four-factor correlated solution. The individual factors and total score demonstrated satisfactory internal consistency reliability for screening purposes. When applying the lowest pre-established cut score (T >/= 60; minimum indication of clinically significant symptoms/impairments), 85 % of the sample had ratings in that range or higher (more severe). Implications for assessment and future research are provided.

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11. Van der Hallen R, Evers K, Boets B, Steyaert J, Noens I, Wagemans J. {{Visual Search in ASD: Instructed Versus Spontaneous Local and Global Processing}}. {J Autism Dev Disord}. 2016.

Visual search has been used extensively to investigate differences in mid-level visual processing between individuals with ASD and TD individuals. The current study employed two visual search paradigms with Gaborized stimuli to assess the impact of task distractors (Experiment 1) and task instruction (Experiment 2) on local-global visual processing in ASD versus TD children. Experiment 1 revealed both groups to be equally sensitive to the absence or presence of a distractor, regardless of the type of target or type of distractor. Experiment 2 revealed a differential effect of task instruction for ASD compared to TD, regardless of the type of target. Taken together, these results stress the importance of task factors in the study of local-global visual processing in ASD.

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12. Venker CE. {{Spoken word recognition in children with autism spectrum disorder: The role of visual disengagement}}. {Autism}. 2016.

Deficits in visual disengagement are one of the earliest emerging differences in infants who are later diagnosed with autism spectrum disorder. Although researchers have speculated that deficits in visual disengagement could have negative effects on the development of children with autism spectrum disorder, we do not know which skills are disrupted or how this disruption takes place. As a first step in understanding this issue, this study investigated the relationship between visual disengagement and a critical skill in early language development: spoken word recognition. Participants were 18 children with autism spectrum disorder (aged 4-7 years). Consistent with our predictions, children with poorer visual disengagement were slower and less accurate to process familiar words; disengagement explained over half of the variance in spoken word recognition. Visual disengagement remained uniquely associated with spoken word recognition after accounting for children’s vocabulary size and age. These findings align with a recently proposed developmental model in which poor visual disengagement decreases the speed and accuracy of real-time spoken word recognition in children with autism spectrum disorder-which, in turn, may negatively affect their language development.

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13. Yanagisawa K, Nakamura N, Tsunashima H, Narita N. {{Proposal of auxiliary diagnosis index for autism spectrum disorder using near-infrared spectroscopy}}. {Neurophotonics}. 2016; 3(3): 031413.

Lack of a diagnostic index is a problem that needs to be overcome in the diagnosis of autism spectrum disorder (ASD), because this problem prevents an objective assessment based on biomarkers. This paper describes the development of a diagnostic index for ASD using near-infrared spectroscopy (NIRS). We investigated continuous prefrontal hemodynamic changes depending on reciprocal disposition of working memory and nonworking memory tasks using two-channel NIRS. NIRS signals in the prefrontal cortex were compared between high-functioning ASD subjects ([Formula: see text]) and typically developed (TD) subjects ([Formula: see text]). The brain activities of the TD subjects were related to experimental design. These results were not confirmed in brain activities of ASD subjects, although the task performance rate was almost equivalent. The brain activities of TD subjects and ASD subjects were evaluated using a weighted separability (WS) index obtained from the feature phase of oxy-hemoglobin and its differential value. Calculation of the [Formula: see text]-test (TD subject versus ASD subject) confirmed that WS was significant. This result showed that the proposed index was useful for evaluation of the brain activity of ASD subjects.

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