1. Eskow KG, Chasson GS, Summers JA. {{A Cross-Sectional Cohort Study of a Large, Statewide Medicaid Home and Community-Based Services Autism Waiver Program}}. {J Autism Dev Disord}. 2014 Sep 3.
State-specific 1915(c) Medicaid Home and Community-Based Services waiver programs have become central in the provision of services specifically tailored to children with autism spectrum disorders (ASD). Using propensity score matching, 130 families receiving waiver services for a child with ASD were matched with and compared to 130 families waiting on the registry (i.e., control group). Results indicate that participants in the waiver group reported more improvement in independent living skills and family quality of life over the last year compared to those on the registry. More frequent intensive individual support services and therapeutic integration were statistically predictive of improvement in a variety of domains. The results suggest that the waiver program may be promising for improving child and family functioning.
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2. Koh JY, Lim J, Byun HR, Yoo MH. {{Abnormalities in the zinc-metalloprotease-BDNF axis may contribute to megalencephaly and cortical hyperconnectivity in young autism spectrum disorder patients}}. {Molecular brain}. 2014 Sep 3;7(1):64.
Whereas aberrant brain connectivity is likely the core pathology of autism-spectrum disorder (ASD), studies do not agree as to whether hypo- or hyper-connectivity is the main underlying problem. Recent functional imaging studies have shown that, in most young ASD patients, cerebral cortical regions appear hyperconnected, and cortical thickness/brain size is increased. Collectively, these findings indicate that developing ASD brains may exist in an altered neurotrophic milieu. Consistently, some ASD patients, as well as some animal models of ASD, show increased levels of brain-derived neurotrophic factor (BDNF). However, how BDNF is upregulated in ASD is unknown. To address this question, we propose the novel hypothesis that a putative zinc-metalloprotease-BDNF (ZMB) axis in the forebrain plays a pivotal role in the development of hyperconnectivity and megalencephaly in ASD.We have previously demonstrated that extracellular zinc at micromolar concentrations can rapidly increase BDNF levels and phosphorylate the receptor tyrosine kinase TrkB via the activation of metalloproteases. The role of metalloproteases in ASD is still uncertain, but in fragile X syndrome, a monogenic disease with an autistic phenotype, the levels of MMP are increased. Early exposure to lipopolysaccharides (LPS) and other MMP activators such as organic mercurials also have been implicated in ASD pathogenesis. The resultant increases in BDNF levels at synapses, especially those involved in the zinc-containing, associative glutamatergic system may produce abnormal brain circuit development. Various genetic mutations that lead to ASD are also known to affect BDNF signaling: some down-regulate, and others up-regulate it. We hypothesize that, although both up- and down-regulation of BDNF may induce autism symptoms, only BDNF up-regulation is associated with the hyperconnectivity and large brain size observed in most young idiopathic ASD patients.To test this hypothesis, we propose to examine the ZMB axis in animal models of ASD. Synaptic zinc can be examined by fluorescence zinc staining. MMP activation can be measured by in situ zymography and Western blot analysis. Finally, regional levels of BDNF can be measured. Validating this hypothesis may shed light on the central pathogenic mechanism of ASD and aid in the identification of useful biomarkers and the development of preventive/therapeutic strategies.
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3. Leblond CS, Nava C, Polge A, Gauthier J, Huguet G, Lumbroso S, Giuliano F, Stordeur C, Depienne C, Mouzat K, Pinto D, Howe J, Lemiere N, Durand CM, Guibert J, Ey E, Toro R, Peyre H, Mathieu A, Amsellem F, Rastam M, Gillberg IC, Rappold GA, Holt R, Monaco AP, Maestrini E, Galan P, Heron D, Jacquette A, Afenjar A, Rastetter A, Brice A, Devillard F, Assouline B, Laffargue F, Lespinasse J, Chiesa J, Rivier F, Bonneau D, Regnault B, Zelenika D, Delepine M, Lathrop M, Sanlaville D, Schluth-Bolard C, Edery P, Perrin L, Tabet AC, Schmeisser MJ, Boeckers TM, Coleman M, Sato D, Szatmari P, Scherer SW, Rouleau GA, Betancur C, Leboyer M, Gillberg C, Delorme R, Bourgeron T. {{Meta-analysis of SHANK Mutations in Autism Spectrum Disorders: A Gradient of Severity in Cognitive Impairments}}. {PLoS genetics}. 2014 Sep;10(9):e1004580.
SHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD), but their prevalence and clinical relevance remain to be determined. Here, we performed a new screen and a meta-analysis of SHANK copy-number and coding-sequence variants in ASD. Copy-number variants were analyzed in 5,657 patients and 19,163 controls, coding-sequence variants were ascertained in 760 to 2,147 patients and 492 to 1,090 controls (depending on the gene), and, individuals carrying de novo or truncating SHANK mutations underwent an extensive clinical investigation. Copy-number variants and truncating mutations in SHANK genes were present in approximately 1% of patients with ASD: mutations in SHANK1 were rare (0.04%) and present in males with normal IQ and autism; mutations in SHANK2 were present in 0.17% of patients with ASD and mild intellectual disability; mutations in SHANK3 were present in 0.69% of patients with ASD and up to 2.12% of the cases with moderate to profound intellectual disability. In summary, mutations of the SHANK genes were detected in the whole spectrum of autism with a gradient of severity in cognitive impairment. Given the rare frequency of SHANK1 and SHANK2 deleterious mutations, the clinical relevance of these genes remains to be ascertained. In contrast, the frequency and the penetrance of SHANK3 mutations in individuals with ASD and intellectual disability-more than 1 in 50-warrant its consideration for mutation screening in clinical practice.
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4. Margari L, Colonna A, Craig F, Gentile M, Giannella G, Lamanna AL, Legrottaglie AR. {{Microphthalmia with Linear Skin Defects (MLS) associated with Autism Spectrum Disorder (ASD) in a patient with Familial 12.9Mb Terminal Xp deletion}}. {BMC pediatrics}. 2014 Sep 2;14(1):220.
BACKGROUND: Microphthalmia with linear skin defects (MLS) syndrome is a rare X-linked dominant male-lethal developmental disorder characterized by unilateral or bilateral microphthalmia and linear skin defects of the face and neck. Additional features affecting the eyes, heart, brain or genitourinary system can occur, corroborating the intra- and interfamilial phenotypic variability. The majority of patients display monosomy of the Xp22.2 region, where the holocytochrome c-type synthase (HCCS) gene is located. CASE PRESENTATION: We describe a 15-year-old-female affected by MLS syndrome and autism spectrum disorder (ASD). ASD has not previously been reported as a component of MLS. Our patient shows a large deletion of 12.9 Mb, involving Xp22.32-p22.2, which encompasses both the HCCS gene and autism X-linked genes. CONCLUSION: Thus, patients with a large deletion at Xp22 might display MLS with ASD, due to the deletion of contiguous genes, although the highly variable phenotype of these patients could be influenced by several genetic mechanisms, including different tissue-specific X-inactivation and somatic mosaicism.
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5. Poletaev AB, Poletaeva AA, Pukhalenko AI, Zamaleeva RS, Cherepanova NA, Frizin DV. {{Adaptive maternal immune deviations as a ground for autism spectrum disorders development in children}}. {Folia medica}. 2014 Apr-Jun;56(2):73-80.
Autism is a vexed problem today. Overall, there is a high frequency of birth children (1:80 – 1:150) with late diagnosed autism spectrum disorders (ASD) and this trend is getting progressively stronger. The causes for the currently increased frequency of ASD and the pathogenesis of ASD are not fully understood yet. One of the most likely mechanisms inducing ASD may be a maternal immune imprinting. This phenomenon is based on transplacental translocation of maternal antibodies of IgG class and, as a consequence, on the epigenetic « tuning » of immune system of the fetus and child. This mechanism provides development of child’s anti-infection resistance before meeting with microorganisms, but it can be also a cause of inborn pathology including the ASD appearance. The quantitative changes in maternal blood serum autoantibodies depend on a specific microbial population, or are induced by environmental chemical pollutants in association with some individual features of the maternal metabolism. These immune changes are adaptive in most cases for the maternal organism, but can be pathogenic for the fetus in some cases. We discuss in the present paper the possibilities to predict the risk from abnormal development of nervous system in fetus and early diagnosis of ASD in high-risk group of children.
6. Radeloff D, Ciaramidaro A, Siniatchkin M, Hainz D, Schlitt S, Weber B, Poustka F, Bolte S, Walter H, Freitag CM. {{Structural Alterations of the Social Brain: A Comparison between Schizophrenia and Autism}}. {PloS one}. 2014;9(9):e106539.
Autism spectrum disorder and schizophrenia share a substantial number of etiologic and phenotypic characteristics. Still, no direct comparison of both disorders has been performed to identify differences and commonalities in brain structure. In this voxel based morphometry study, 34 patients with autism spectrum disorder, 21 patients with schizophrenia and 26 typically developed control subjects were included to identify global and regional brain volume alterations. No global gray matter or white matter differences were found between groups. In regional data, patients with autism spectrum disorder compared to typically developed control subjects showed smaller gray matter volume in the amygdala, insula, and anterior medial prefrontal cortex. Compared to patients with schizophrenia, patients with autism spectrum disorder displayed smaller gray matter volume in the left insula. Disorder specific positive correlations were found between mentalizing ability and left amygdala volume in autism spectrum disorder, and hallucinatory behavior and insula volume in schizophrenia. Results suggest the involvement of social brain areas in both disorders. Further studies are needed to replicate these findings and to quantify the amount of distinct and overlapping neural correlates in autism spectrum disorder and schizophrenia.
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7. Stavropoulos KK, Carver LJ. {{Effect of Familiarity on Reward Anticipation in Children with and without Autism Spectrum Disorders}}. {PloS one}. 2014;9(9):e106667.
BACKGROUND: Previous research on the reward system in autism spectrum disorders (ASD) suggests that children with ASD anticipate and process social rewards differently than typically developing (TD) children-but has focused on the reward value of unfamiliar face stimuli. Children with ASD process faces differently than their TD peers. Previous research has focused on face processing of unfamiliar faces, but less is known about how children with ASD process familiar faces. The current study investigated how children with ASD anticipate rewards accompanied by familiar versus unfamiliar faces. METHODS: The stimulus preceding negativity (SPN) of the event-related potential (ERP) was utilized to measure reward anticipation. Participants were 6- to 10-year-olds with (N = 14) and without (N = 14) ASD. Children were presented with rewards accompanied by incidental face or non-face stimuli that were either familiar (caregivers) or unfamiliar. All non-face stimuli were composed of scrambled face elements in the shape of arrows, controlling for visual properties. RESULTS: No significant differences between familiar versus unfamiliar faces were found for either group. When collapsing across familiarity, TD children showed larger reward anticipation to face versus non-face stimuli, whereas children with ASD did not show differential responses to these stimulus types. Magnitude of reward anticipation to faces was significantly correlated with behavioral measures of social impairment in the ASD group. CONCLUSIONS: The findings do not provide evidence for differential reward anticipation for familiar versus unfamiliar face stimuli in children with or without ASD. These findings replicate previous work suggesting that TD children anticipate rewards accompanied by social stimuli more than rewards accompanied by non-social stimuli. The results do not support the idea that familiarity normalizes reward anticipation in children with ASD. Our findings also suggest that magnitude of reward anticipation to faces is correlated with levels of social impairment for children with ASD.
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8. van Diessen E, Senders J, Jansen FE, Boersma M, Bruining H. {{Increased power of resting-state gamma oscillations in autism spectrum disorder detected by routine electroencephalography}}. {European archives of psychiatry and clinical neuroscience}. 2014 Sep 3.
Experimental studies suggest that increased resting-state power of gamma oscillations is associated with autism spectrum disorder (ASD). To extend the clinical applicability of this finding, we retrospectively investigated routine electroencephalography (EEG) recordings of 19 patients with ASD and 19 age- and gender-matched controls. Relative resting-state condition gamma spectral power was variable, but on average significantly increased in children with ASD. This effect remained when excluding electrodes associated with myogenic gamma activity. These findings further indicate that increased resting-state gamma activity characterizes a subset of ASD and may also be detected by routine EEG as a clinically accessible and well-tolerated investigation.
