1. Antshel KM, Zhang-James Y, Wagner K, Ledesma A, Faraone SV. {{An update on the comorbidity of ASD and ADHD: A focus on clinical management}}. {Expert Rev Neurother};2016 (Jan 25)
Attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) commonly co-occur. With the DSM-5, clinicians are permitted to make an ASD diagnosis in the context of ADHD. In earlier versions of the DSM, this was not acceptable. Both ASD and ADHD are reported to have had substantial increases in prevalence within the past 10 years. As a function of both the increased prevalence of both disorders as well as the ability to make an ASD diagnosis in ADHD, there has been a significant amount of research focusing on the comorbidity between ADHD and ASD in the past few years. Here, we provide an update on the biological, cognitive and behavioral overlap/distinctiveness between the two neurodevelopmental disorders with a focus on data published in the last four years. Treatment strategies for the comorbid condition as well as future areas of research and clinical need are discussed.
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2. Azad GF, Locke J, Downey MM, Xie M, Mandell DS. {{One-to-One Assistant Engagement in Autism Support Classrooms}}. {Teach Educ Spec Educ};2015 (Nov 1);38(4):337-346.
Classroom assistants and one-to-one assistants are an important part of the staffing structure of many autism support classrooms. Limited studies, however, have examined how one-to-one assistants spend their time in the classroom. The purpose of this article was to examine the percentage of time one-to-one assistants were engaged in instruction or support of students with autism and to determine the factors associated with their engagement. Direct observations were conducted in 46 autism support classrooms. Teachers and classroom assistants were engaged in instruction or support 98% and 91% of the time, respectively. One-to-one assistants were engaged in instruction or support 57% of the time. Classroom assistants’ and one-to-one assistants’ engagement was significantly correlated. The low rate of one-to-one assistants’ engagement suggests an inefficient use of an important resource.
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3. Ballantyne CJ, Nunez M. {{Developmental trajectories of hierarchical visuo-spatial processing in fragile X syndrome and ASD: Within- and cross-syndrome variability}}. {Res Dev Disabil};2016 (Jan 22);51-52:103-115.
BACKGROUND/AIMS: Despite the advances in understanding visuo-spatial processing in developmental disorders such as ASD and fragile X syndrome (FXS), less is known about the profile of those with a comorbid diagnosis, or the role of within-disorder disparities between individuals across the ASD spectrum. METHODS AND PROCEDURES: Using a developmental trajectory approach, we tested 5 groups of children: Typically developing, FXS, FXS+ASD, ASD individuals who had low-moderate symptoms (HFA) and ASD individuals who had severe symptoms (LFA). Symptoms of ASD were assessed using the Childhood Autism Rating Scale: CARS and hierarchical visuo-spatial processing was assessed using the Navon task. OUTCOMES AND RESULTS: Crucially, results differed between HFA and LFA participants. Furthermore, the pattern of results differed between those who had a diagnosis of FXS only and FXS+ASD. Poorer performance within the FXS groups and the group who are low functioning on the ASD spectrum indicated a delayed developmental rate compared to typical controls. CONCLUSIONS AND IMPLICATIONS: This study showed that diagnosis and severity of symptoms are indicative of differences in visuo-spatial processing styles. It is important that heterogeneity within FXS and ASD populations are considered in subsequent studies and look beyond diagnostic group differences.
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4. Bekhet AK. {{The Mediating Effects of Positive Cognitions on Autism Caregivers’ Depression and Their Children’s Challenging Behaviors}}. {Arch Psychiatr Nurs};2016 (Feb);30(1):13-18.
Caregivers of persons with Autism Spectrum Disorders (ASD) are prone to depression and psychological problems, which have an impact on their children’s challenging behaviors. Positive cognitions include specific positive thinking patterns that enhance one’s ability to effectively manage daily activities and promote mental health. The purpose of this research is to test the mediating effects of positive cognitions on the relationship between caregivers’ depression and their children’s challenging behaviors among 117 caregivers of persons with ASD. Positive cognitions were found to have mediating effects on the relationship between caregiver’s depression and their children’s challenging behaviors in this sample of caregivers of persons with ASD. Nurses are in a strategic position to include in their interventions those strategies that strengthen positive cognitions in order to improve the caregivers’ positive cognitions and well-being, which, in turn will have an impact on their children’s challenging behaviors.
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5. Chrobak AA, Soltys Z. {{Bergmann Glia, Long-Term Depression, and Autism Spectrum Disorder}}. {Mol Neurobiol};2016 (Jan 26)
Bergmann glia (BG), a specific type of radial astrocytes in the cerebellum, play a variety of vital functions in the development of this structure. However, the possible role of BG in the development of abnormalities observed in individuals with autism spectrum disorder (ASD) seems to be underestimated. One of the most consistent findings observed in ASD patients is loss of Purkinje cells (PCs). Such a defect may be caused by dysregulation of glutamate homeostasis, which is maintained mainly by BG. Moreover, these glial cells are involved in long-term depression (LTD), a form of plasticity which can additionally subserve neuroprotective functions. The aim of presented review is to summarize the current knowledge about interactions which occur between PC and BG, with special emphasis on those which are relevant to the survival and proper functioning of cerebellar neurons.
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6. Felice C, Leoncini S, Signorini C, Cortelazzo A, Rovero P, Durand T, Ciccoli L, Papini AM, Hayek J. {{Rett syndrome: An autoimmune disease?}}. {Autoimmun Rev};2016 (Jan 22)
Rett syndrome (RTT) is a devastating neurodevelopmental disease, previously included into the autistic spectrum disorders, affecting almost exclusively females (frequency 1:10,000). RTT leads to intellective deficit, purposeful hands use loss and late major motor impairment besides featuring breathing disorders, epilepsy and increased risk of sudden death. The condition is caused in up to 95% of the cases by mutations in the X-linked methyl-CpG binding protein 2 (MECP2) gene. Our group has shown a number of previously unrecognized features, such as systemic redox imbalance, chronic inflammatory status, respiratory bronchiolitis-associated interstitial lung disease-like lung disease, and erythrocyte morphology changes. While evidence on an intimate involvement of MeCP2 in the immune response is cumulating, we have recently shown a cytokine dysregulation in RTT. Increasing evidence on the relationship between MeCP2 and an immune dysfunction is reported, with, apparently, a link between MeCP2 gene polymorphisms and autoimmune diseases, including primary Sjogren’s syndrome, systemic lupus erythematosus, rheumatoid arthritis, and systemic sclerosis. Antineuronal (i.e., brain proteins) antibodies have been shown in RTT. Recently, high levels of anti-N-glucosylation (N-Glc) IgM serum autoantibodies [i.e., anti-CSF114(N-Glc) IgMs] have been detected by our group in a statistically significant number of RTT patients. In the current review, the Authors explore the current evidence, either in favor or against, the presence of an autoimmune component in RTT.
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7. Gogou M, Spilioti M, Tramma D, Papadopoulou-Alataki E, Evangeliou A. {{Succinic Semialdehyde Dehydrogenase Deficiency Presenting as Autism Spectrum Disorder}}. {Indian J Pediatr};2016 (Jan 25)
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8. Hanaie R, Mohri I, Kagitani-Shimono K, Tachibana M, Matsuzaki J, Hirata I, Nagatani F, Watanabe Y, Fujita N, Taniike M. {{White matter volume in the brainstem and inferior parietal lobule is related to motor performance in children with autism spectrum disorder: A voxel-based morphometry study}}. {Autism Res};2016 (Jan 25)
Many studies have reported poor motor performance in autism spectrum disorder (ASD); however, the underlying brain mechanisms remain unclear. Recent neuroimaging studies have suggested that abnormalities of the white matter (WM) are related to the features of ASD. In this study, we used voxel-based morphometry (VBM) to investigate which WM regions correlate with motor performance in children with ASD, and whether the WM volume in those brain regions differed between children with ASD and typically developing (TD) children. The subjects included 19 children with ASD and 20 TD controls. Motor performance was assessed using the Movement Assessment Battery for Children 2 (M-ABC 2). Children with ASD showed poorer motor performance than did the controls. There was a significant positive correlation between the total test score on the M-ABC 2 and the volume of WM in the brainstem and WM adjacent to the left supramarginal gyrus (SMG). In addition, compared with the TD controls, children with ASD had a decreased volume of WM in the brainstem and adjacent to the left intraparietal sulcus, which is close to the SMG. These findings suggest that structural changes in the WM in the brainstem and left inferior parietal lobule may contribute to poor motor performance in children with ASD. Autism Res 2016. (c) 2016 International Society for Autism Research, Wiley Periodicals, Inc.
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9. Liu Z, Li X, Zhang JT, Cai YJ, Cheng TL, Cheng C, Wang Y, Zhang CC, Nie YH, Chen ZF, Bian WJ, Zhang L, Xiao J, Lu B, Zhang YF, Zhang XD, Sang X, Wu JJ, Xu X, Xiong ZQ, Zhang F, Yu X, Gong N, Zhou WH, Sun Q, Qiu Z. {{Autism-like behaviours and germline transmission in transgenic monkeys overexpressing MeCP2}}. {Nature};2016 (Jan 25)
Methyl-CpG binding protein 2 (MeCP2) has crucial roles in transcriptional regulation and microRNA processing. Mutations in the MECP2 gene are found in 90% of patients with Rett syndrome, a severe developmental disorder with autistic phenotypes. Duplications of MECP2-containing genomic segments cause the MECP2 duplication syndrome, which shares core symptoms with autism spectrum disorders. Although Mecp2-null mice recapitulate most developmental and behavioural defects seen in patients with Rett syndrome, it has been difficult to identify autism-like behaviours in the mouse model of MeCP2 overexpression. Here we report that lentivirus-based transgenic cynomolgus monkeys (Macaca fascicularis) expressing human MeCP2 in the brain exhibit autism-like behaviours and show germline transmission of the transgene. Expression of the MECP2 transgene was confirmed by western blotting and immunostaining of brain tissues of transgenic monkeys. Genomic integration sites of the transgenes were characterized by a deep-sequencing-based method. As compared to wild-type monkeys, MECP2 transgenic monkeys exhibited a higher frequency of repetitive circular locomotion and increased stress responses, as measured by the threat-related anxiety and defensive test. The transgenic monkeys showed less interaction with wild-type monkeys within the same group, and also a reduced interaction time when paired with other transgenic monkeys in social interaction tests. The cognitive functions of the transgenic monkeys were largely normal in the Wisconsin general test apparatus, although some showed signs of stereotypic cognitive behaviours. Notably, we succeeded in generating five F1 offspring of MECP2 transgenic monkeys by intracytoplasmic sperm injection with sperm from one F0 transgenic monkey, showing germline transmission and Mendelian segregation of several MECP2 transgenes in the F1 progeny. Moreover, F1 transgenic monkeys also showed reduced social interactions when tested in pairs, as compared to wild-type monkeys of similar age. Together, these results indicate the feasibility and reliability of using genetically engineered non-human primates to study brain disorders.
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10. Oyarzabal A, Bravo-Alonso I, Sanchez-Arago M, Rejas MT, Merinero B, Garcia-Cazorla A, Artuch R, Ugarte M, Rodriguez-Pombo P. {{Mitochondrial response to the BCKDK-deficiency: Some clues to understand the positive dietary response in this form of autism}}. {Biochim Biophys Acta};2016 (Jan 22)
Mutations on the mitochondrial-expressed Branched Chain alpha-Keto acid Dehydrogenase Kinase (BCKDK) gene have been recently associated with a novel dietary-treatable form of autism. But, being a mitochondrial metabolism disease, little is known about the impact on mitochondrial performance. Here, we analyze the mitochondrial response to the BCKDK-deficiency in patient’s primary fibroblasts by measuring bioenergetics, ultra-structural and dynamics parameters. A two-fold increase in superoxide anion production, together with a reduction in ATP-linked respiration and intracellular ATP levels (down to 60%) detected in mutants fibroblasts point to a general bioenergetics depletion that could affect the mitochondrial dynamics and cell fate. Ultrastructure analysis of BCKDK-deficient fibroblasts shows an increased number of elongated mitochondria, apparently associated with changes in the mediator of inner mitochondria membrane fusion, GTPase OPA1 forms, and in the outer mitochondrial membrane, mitofusin 2/MFN2. Our data support a possible hyperfusion response of BCKDK-deficient mitochondria to stress. Cellular fate also seems to be affected as these fibroblasts show an altered proportion of the cells on G0/G1 and G2/M phases. Knockdown of BCKDK gene in control fibroblasts recapitulates most of these features. Same BCKDK-knockdown in a MSUD patient fibroblasts unmasks the direct involvement of the accelerated BCAAs catabolism in the mitochondrial dysfunction. All these data gives us a clue to understand the positive dietary response to an overload of branched-chain amino acids. We hypothesize that a combination of the current therapeutic option with a protocol that considers the oxidative damage and energy expenditure, addressing the patients’ individuality, might be useful for the physicians.
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11. van Boxtel JJ, Dapretto M, Lu H. {{Intact recognition, but attenuated adaptation, for biological motion in youth with autism spectrum disorder}}. {Autism Res};2016 (Jan 25)
Given the ecological importance of biological motion and its relevance to social cognition, considerable effort has been devoted over the past decade to studying biological motion perception in autism. However, previous studies have asked observers to detect or recognize briefly presented human actions placed in isolation, without spatial or temporal context. Research on typical populations has shown the influence of temporal context in biological motion perception: prolonged exposure to one action gives rise to an aftereffect that biases perception of a subsequently displayed action. Whether people with autism spectrum disorders (ASD) show such adaptation effects for biological motion stimuli remains unknown. To address this question, this study examined how well youth with ASD recognize ambiguous actions and adapt to recently-observed actions. Compared to typically-developing (TD) controls, youth with ASD showed no differences in perceptual boundaries between actions categories, indicating intact ability in recognizing actions. However, children with ASD showed weakened adaptation to biological motion. It is unlikely that the reduced action adaptability in autism was due to delayed developmental trajectory, as older children with ASD showed weaker adaptation to actions than younger children with ASD. Our results further suggest that high-level (i.e., action) processing weakens with age for children with ASD, but this change may be accompanied by a potentially compensatory mechanism based on more involvement of low-level (i.e., motion) processing. Autism Res 2016. (c) 2016 International Society for Autism Research, Wiley Periodicals, Inc.
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12. Yoshimura Y, Kikuchi M, Hiraishi H, Hasegawa C, Takahashi T, Remijn GB, Oi M, Munesue T, Higashida H, Minabe Y, Kojima H. {{Atypical development of the central auditory system in young children with Autism spectrum disorder}}. {Autism Res};2016 (Jan 25)
The P1m component of the auditory evoked magnetic field is the earliest cortical response associated with language acquisition. However, the growth curve of the P1m component is unknown in both typically developing (TD) and atypically developing children. The aim of this study is to clarify the developmental pattern of this component when evoked by binaural human voice stimulation using child-customized magnetoencephalography. A total of 35 young TD children (32-121 months of age) and 35 children with autism spectrum disorder (ASD) (38-111 months of age) participated in this study. This is the first report to demonstrate an inverted U-shaped growth curve for the P1m dipole intensity in the left hemisphere in TD children. In addition, our results revealed a more diversified age-related distribution of auditory brain responses in 3- to 9-year-old children with ASD. These results demonstrate the diversified growth curve of the P1m component in ASD during young childhood, which is a crucial period for first language acquisition. Autism Res 2016. (c) 2016 International Society for Autism Research, Wiley Periodicals, Inc.
