1. Aldbass AM, Bhat RS, El-Ansary A. {{Protective and therapeutic potency of N-acetyl-cysteine on propionic acid-induced biochemical autistic features in rats}}. {Journal of neuroinflammation}. 2013 Mar 27;10(1):42.
BACKGROUND: The investigation of the environmental contribution for developmental neurotoxicity is very critical. Many environmental chemical exposures are now thought to contribute to the development of neurological disorders, especially in children. Results from animal studies may guide investigations of human populations towards identifying either environmental toxicants that cause or drugs that protect from neurotoxicity and may help in treatment of neurodevelopmental disorders. OBJECTIVE: To study both the protective and therapeutic effects of N-acetyl cysteine on brain intoxication induced by propionic acid (PPA) in rats. METHODS: Twenty-eight young male Western Albino rats were enrolled in the present study. They were grouped into four equal groups, each of 7 animals. Group 1: control group, orally received only phosphate buffered saline; Group 2: PPA-treated group, received a neurotoxic dose of of PPA of 250 mg/kg body weight/day for 3 days; Group 3: protective group, received a dose of 50 mg/kg body weight/day N-acetyl-cysteine for one week followed by a similar dose of PPA for 3 days; and Group 4: therapeutic group, treated with the same dose of N-acetyl cysteine after being treated with the toxic dose of PPA. Serotonin, interferon gamma (IFN-gamma), and glutathione-s-transferase activity, together with Comet DNA were assayed in the brain tissue of rats in all different groups. RESULTS: The obtained data showed that PPA caused multiple signs of brain toxicity as measured by depletion of serotonin (5HT), increase in IFN-gamma and inhibition of glutathione-s-transferase activity as three biomarkers of brain dysfunction. Additionally Comet DNA assay showed remarkably higher tail length, tail DNA % damage and tail moment. N-acetyl-cysteine was effective in counteracting the neurotoxic effects of PPA. CONCLUSIONS: The low dose and the short duration of N-acetyl-cysteine treatment tested in the present study showed much more protective rather than therapeutic effects on PPA-induced neurotoxicity in rats, as there was a remarkable amelioration in the impaired biochemical parameters representing neurochemical, inflammatory, detoxification and DNA damage processes.
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2. Chlebowski C, Robins DL, Barton ML, Fein D. {{Large-Scale Use of the Modified Checklist for Autism in Low-Risk Toddlers}}. {Pediatrics}. 2013 Mar 25.
OBJECTIVE:The purpose of the study was to examine use of the Modified Checklist for Autism in Toddlers (M-CHAT) as an autism-specific screening instrument in a large, geographically diverse pediatrics-based sample.METHODS:The M-CHAT and the M-CHAT Follow-Up (M-CHAT/F) were used to screen 18 989 toddlers at pediatric well-child visits in 2 US geographic regions. Pediatricians directly referred children to ascertain potential missed screening cases. Screen-positive children received the M-CHAT/F; children who continued to screen positive after the M-CHAT/F received a diagnostic evaluation.RESULTS:Results indicated that 54% of children who screened positive on the M-CHAT and M-CHAT/F presented with an autism spectrum disorder (ASD), and 98% presented with clinically significant developmental concerns warranting intervention. An M-CHAT total score cutoff of >/=3 identifies nearly all screen-positive cases, and for ease of scoring the use of only the M-CHAT total score cutoff is recommended. An M-CHAT total score of 7 serves as an appropriate clinical cutoff, and providers can bypass the M-CHAT/F and refer immediately to evaluation and intervention if a child obtains a score of >/=7.CONCLUSIONS:This study provides empirical support for the utility of population screening for ASD with the use of the M-CHAT in a primary care setting. Results suggest that the M-CHAT continues to be an effective screening instrument for ASD when the 2-step screening process is used. The M-CHAT is widely used at pediatric offices, and this study provides updated results to facilitate use and scoring of the M-CHAT by clinical providers.
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3. Cook R, Brewer R, Shah P, Bird G. {{Alexithymia, Not Autism, Predicts Poor Recognition of Emotional Facial Expressions}}. {Psychological science}. 2013 Mar 25.
Despite considerable research into whether face perception is impaired in autistic individuals, clear answers have proved elusive. In the present study, we sought to determine whether co-occurring alexithymia (characterized by difficulties interpreting emotional states) may be responsible for face-perception deficits previously attributed to autism. Two experiments were conducted using psychophysical procedures to determine the relative contributions of alexithymia and autism to identity and expression recognition. Experiment 1 showed that alexithymia correlates strongly with the precision of expression attributions, whereas autism severity was unrelated to expression-recognition ability. Experiment 2 confirmed that alexithymia is not associated with impaired ability to detect expression variation; instead, results suggested that alexithymia is associated with difficulties interpreting intact sensory descriptions. Neither alexithymia nor autism was associated with biased or imprecise identity attributions. These findings accord with the hypothesis that the emotional symptoms of autism are in fact due to co-occurring alexithymia and that existing diagnostic criteria may need to be revised.
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4. D’Cruz AM, Ragozzino ME, Mosconi MW, Shrestha S, Cook EH, Sweeney JA. {{Reduced behavioral flexibility in autism spectrum disorders}}. {Neuropsychology}. 2013 Mar;27(2):152-60.
Objective: Restricted and repetitive behaviors, and a pronounced preference for behavioral and environmental consistency, are distinctive characteristics of autism spectrum disorders (ASD). Whether these clinical features of ASD are related to fundamental neuropsychological impairments in behavioral flexibility remains to be clarified. Method: Forty-one individuals with ASD and 37 matched controls performed a probabilistic reversal learning task to assess behavioral flexibility. Participants learned to choose the correct stimulus location from a pair of locations to win points (acquisition). After making the correct choice over multiple trials, the rewarded stimulus location changed without warning (reversal). Feedback was provided on an 80:20 probabilistic schedule, with 80% of correct choices and 20% of incorrect choices randomly reinforced. Results: ASD and control participants performed comparably during acquisition. At reversal, ASD participants initially chose the new correct location as quickly as controls, but then more frequently reverted back to the previously preferred response. The ASD group also more frequently shifted back to the previous response choice immediately following intermittent non-reinforcement of the new correct response. The number of regressive errors was positively correlated with independently ascertained clinical ratings of restricted and repetitive behaviors, but not other core features of ASD. Conclusions: Restricted and repetitive behaviors in ASD are associated with neurocognitive deficits in flexible choice behavior. Preclinical research has established that frontostriatal circuitry supports flexibility on reversal learning tasks. Thus, alterations in this circuitry may contribute to behavioral rigidity in ASD and represent a target for therapeutic intervention. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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5. Girirajan S, Johnson RL, Tassone F, Balciuniene J, Katiyar N, Fox K, Baker C, Srikanth A, Yeoh KH, Khoo SJ, Nauth TB, Hansen R, Ritchie M, Hertz-Picciotto I, Eichler EE, Pessah IN, Selleck SB. {{Global increases in both common and rare copy number load associated with autism}}. {Hum Mol Genet}. 2013 Mar 27.
Children with autism have an elevated frequency of large, rare copy number variants (CNVs). However, the global load of deletions or duplications, per se, and their size, location and relationship to clinical manifestations of autism have not been documented. We examined CNV data from 516 individuals with autism or typical development from the population-based Childhood Autism Risks from Genetics and Environment (CHARGE) study. We interrogated 120 regions flanked by segmental duplications (genomic hotspots) for events >50 kbp and the entire genomic backbone for variants >300 kbp using a custom targeted DNA microarray. This analysis was complemented by a separate study of five highly dynamic, hotspots associated with autism or developmental delay syndromes using a finely-tiled array platform (>1 kbp) in 142 children matched for gender and ethnicity. In both studies, a significant increase in the number of base pairs of duplication, but not deletion, was associated with autism. Significantly elevated levels of CNV load remained after removal of rare and likely pathogenic events. Further, the entire CNV load detected with the finely-tiled array was contributed by common variants. The impact of this variation was assessed by examining the correlation of clinical outcomes with CNV load. The level of personal and social skills, measured by Vineland Adaptive Behavior Scales, negatively correlated (Spearman’s r=-0.13, p=0.034) with the duplication CNV load for the affected children; the strongest association was found for communication (p=0.048) and socialization (p=0.022) scores. We propose that CNV load, predominantly increased genomic base pairs of duplication, predisposes to autism.
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6. Green J, Wan MW, Guiraud J, Holsgrove S, McNally J, Slonims V, Elsabbagh M, Charman T, Pickles A, Johnson M, The BT. {{Intervention for Infants at Risk of Developing Autism: A Case Series}}. {J Autism Dev Disord}. 2013 Mar 27.
Theory and evidence suggest the potential value of prodromal intervention for infants at risk of developing autism. We report an initial case series (n = 8) of a parent-mediated, video-aided and interaction-focused intervention with infant siblings of autistic probands, beginning at 8-10 months of age. We outline the theory and evidence base behind this model and present data on feasibility, acceptability and measures ranging from parent-infant social interaction, to infant atypical behaviors, attention and cognition. The intervention proves to be both feasible and acceptable to families. Measurement across domains was successful and on larger samples promise to be an effective test of whether such an intervention in infancy will modify emergent atypical developmental trajectories in infants at risk for autism.
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7. Harper A, Dyches TT, Harper J, Roper SO, South M. {{Respite Care, Marital Quality, and Stress in Parents of Children with Autism Spectrum Disorders}}. {J Autism Dev Disord}. 2013 Mar 26.
Parents of children with autism spectrum disorders (ASD) are at risk for having higher stress and lower marital quality than other parents. Survey data regarding respite care, marital quality, and daily hassles and uplifts were obtained from 101 mother-father dyads who were together raising at least one child with ASD (total # of children = 118). Number of hours of respite care was positively related to improved marital quality for both husbands and wives, such that a 1-h increase in weekly respite care was associated with a one-half standard deviation increase in marital quality. This relationship was significantly mediated by perceived daily stresses and uplifts in both husbands and wives. More respite care was associated with increased uplifts and reduced stress; increased uplifts were associated with improved marital quality; and more stress was associated with reduced marital quality. The number of children in the family was associated with greater stress, and reduced relational quality and daily uplifts. Results suggest policymakers and practitioners should develop supports for providing respite for families raising children with ASD.
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8. Hill DA, Kearley R. {{Autism litigation: Outcomes for 2010, trends in decision making and changes in diagnostic criteria}}. {Research in developmental disabilities}. 2013 Mar 22;34(5):1843-8.
The diagnosis of autism spectrum disorder has systematically risen since Kanner’s description in 1943 and Asperger’s definition in 1944. An increase in numbers has met with an increase in litigation regarding autism spectrum disorder (ASD) and the Individuals with Disabilities Education Improvement Act (IDEIA). Outcomes that first favored parents (2002-2004) have moved to outcomes favoring school districts. The authors update the reader on case outcomes for 2010 and discuss how pending changes in legislation and diagnostic criteria may impact navigation through the education system as individuals seek a free appropriate public education (FAPE) and placement in the least restrictive environment (LRE).
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9. Jiang YV, Capistrano CG, Esler AN, Swallow KM. {{Directing attention based on incidental learning in children with autism spectrum disorder}}. {Neuropsychology}. 2013 Mar;27(2):161-9.
Objective: Attention is a complex construct that taps into multiple mechanisms. One type of attention that is underinvestigated in autism is incidentally or implicitly guided attention. The purpose of this study is to characterize how children with autism spectrum disorder (ASD) direct spatial attention based on incidental learning. Method: Children with high-functioning ASD and typically developing children engaged in a visual search task. For the first half of the study, over multiple trials, the target was more often found in some locations than other locations. For the second half, the target was equally likely to appear in all locations. We measured search performance for targets located in the high-probability and low-probability locations. Results: Children with ASD were able to direct spatial attention using incidentally learned information about the target’s location probability. Although unaware of the experimental manipulation, children with ASD were faster and more efficient in finding a target in the high-probability locations than low-probability locations, and this bias dissipated after the target’s location probability was even. The pace and magnitude of learning, as well as later adjustment to new statistics, were comparable between children with ASD and typically developing children. Conclusions: Incidentally learned attention is preserved in children with ASD. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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10. Kakooza-Mwesige A, Ssebyala K, Karamagi C, Kiguli S, Smith K, Anderson MC, Croen LA, Trevathan E, Hansen R, Smith D, Grether JK. {{Adaptation of the ‘ten questions’ to screen for autism and other neuro-developmental disorders in Uganda}}. {Autism}. 2013 Mar 27.
Neurodevelopmental disorders are recognized to be relatively common in developing countries but little data exist for planning effective prevention and intervention strategies. In particular, data on autism spectrum disorders are lacking. For application in Uganda, we developed a 23-question screener (23Q) that includes the Ten Questions screener and additional questions on autism spectrum disorder behaviors. We then conducted household screening of 1169 children, 2-9 years of age, followed by clinical assessment of children who screened positive and a sample of those who screened negative to evaluate the validity of the screener. We found that 320 children (27% of the total) screened positive and 68 children received a clinical diagnosis of one or more moderate to severe neurodevelopmental disorders (autism spectrum disorder; cerebral palsy; epilepsy; cognitive, speech and language, hearing, or vision impairment), including 8 children with autism spectrum disorders. Prevalence and validity of the screener were evaluated under different statistical assumptions. Sensitivity of the 23Q ranged from 0.55 to 0.80 and prevalence for >/=1 neurodevelopmental disorders from 7.7/100 children to 12.8/100 children depending on which assumptions were used. The combination of screening positive on both autism spectrum disorders and Ten Questions items was modestly successful in identifying a subgroup of children at especially high risk of autism spectrum disorders. We recommend that autism spectrum disorders and related behavioral disorders be included in studies of neurodevelopmental disorders in low-resource settings to obtain essential data for planning local and global public health responses.
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11. Mandell DS. {{Adults with Autism-A New Minority}}. {Journal of general internal medicine}. 2013 Mar 27.
