1. Emond P, Mavel S, Aidoud N, Nadal-Desbarats L, Montigny F, Bonnet-Brilhault F, Barthelemy C, Merten M, Sarda P, Laumonnier F, Vourc’h P, Blasco H, Andres CR. {{GC-MS-based urine metabolic profiling of autism spectrum disorders}}. {Anal Bioanal Chem};2013 (Apr 10)
Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders resulting from multiple factors. Diagnosis is based on behavioural and developmental signs detected before 3 years of age, and there is no reliable biological marker. The purpose of this study was to evaluate the value of gas chromatography combined with mass spectroscopy (GC-MS) associated with multivariate statistical modeling to capture the global biochemical signature of autistic individuals. GC-MS urinary metabolic profiles of 26 autistic and 24 healthy children were obtained by liq/liq extraction, and were or were not subjected to an oximation step, and then were subjected to a persilylation step. These metabolic profiles were then processed by multivariate analysis, in particular orthogonal partial least-squares discriminant analysis (OPLS-DA, R 2Y(cum) = 0.97, Q 2(cum) = 0.88). Discriminating metabolites were identified. The relative concentrations of the succinate and glycolate were higher for autistic than healthy children, whereas those of hippurate, 3-hydroxyphenylacetate, vanillylhydracrylate, 3-hydroxyhippurate, 4-hydroxyphenyl-2-hydroxyacetate, 1H-indole-3-acetate, phosphate, palmitate, stearate, and 3-methyladipate were lower. Eight other metabolites, which were not identified but characterized by a retention time plus a quantifier and its qualifier ion masses, were found to differ between the two groups. Comparison of statistical models leads to the conclusion that the combination of data obtained from both derivatization techniques leads to the model best discriminating between autistic and healthy groups of children.
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2. Harfterkamp M, Buitelaar JK, Minderaa RB, van de Loo-Neus G, van der Gaag RJ, Hoekstra PJ. {{Long-Term Treatment with Atomoxetine for Attention-Deficit/Hyperactivity Disorder Symptoms in Children and Adolescents with Autism Spectrum Disorder: An Open-Label Extension Study}}. {J Child Adolesc Psychopharmacol};2013 (Apr 11)
Abstract Objective: The efficacy and tolerability of long-term treatment with atomoxetine for symptoms of attention-deficit/hyperactivity disorder (ADHD) in children with autism spectrum disorder (ASD) has not been established. Methods: In this study, 88 patients 6-17 years of age, with ADHD and ASD, were treated with 1.2 mg/kg/day atomoxetine for 20 weeks as follow-up of an 8 week double-blind placebo-controlled period. Primary endpoint was the ADHD Rating Scale (ADHD-RS). Results: After 8 weeks of initial treatment, the mean total, inattention, and hyperactivity-impulsivity ADHD-RS further decreased significantly from 34.9 to 27.0 for the total ADHD-RS, from 18.3 to 14.5 for the ADHD-RS inattention subscale, and from 16.5 to 12.6 for the hyperactivity-impulsivity subscale. Adverse events were mild and tended to diminish over time during continued treatment, especially regarding nausea and fatigue. There were no serious adverse events. Conclusions: The results of the present analysis suggest that continued treatment with atomoxetine up to 28 weeks further improve ADHD symptoms in children and adolescents with ASD, while adverse events tend to subside. Future studies investigating the long-term efficacy of atomoxetine in children and adolescents with ASD should be randomized and placebo controlled. This study has been registered in ClinicalTrials.gov ( www.clinicaltrials.gov ) under registration number NCT00380692.
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3. Korf BR, Rehm HL. {{New approaches to molecular diagnosis}}. {JAMA};2013 (Apr 10);309(14):1511-1521.
Advances in understanding the molecular basis of rare and common disorders, as well as in the technology of DNA analysis, are rapidly changing the landscape of molecular genetic and genomic testing. High-resolution molecular cytogenetic analysis can now detect deletions or duplications of DNA of a few hundred thousand nucleotides, well below the resolution of the light microscope. Diagnostic testing for « single-gene » disorders can be done by targeted analysis for specific mutations, by sequencing a specific gene to scan for mutations, or by analyzing multiple genes in which mutation may lead to a similar phenotype. The advent of massively parallel next-generation sequencing facilitates the analysis of multiple genes and now is being used to sequence the coding regions of the genome (the exome) for clinical testing. Exome sequencing requires bioinformatic analysis of the thousands of variants that are identified to find one that is contributing to the pathology; there is also a possibility of incidental identification of other medically significant variants, which may complicate genetic counseling. DNA testing can also be used to identify variants that influence drug metabolism or interaction of a drug with its cellular target, allowing customization of choice of drug and dosage. Exome and genome sequencing are being applied to identify specific gene changes in cancer cells to guide therapy, to identify inherited cancer risk, and to estimate prognosis. Genomic testing may be used to identify risk factors for common disorders, although the clinical utility of such testing is unclear. Genetic and genomic tests may raise new ethical, legal, and social issues, some of which may be addressed by existing genetic nondiscrimination legislation, but which also must be addressed in the course of genetic counseling. The purpose of this article is to assist physicians in recognizing where new approaches to genetic and genomic testing may be applied clinically and in being aware of the principles of interpretation of test results.
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4. Larsson G, Julu PO, Witt Engerstrom I, Sandlund M, Lindstrom B. {{Normal reactions to orthostatic stress in Rett syndrome}}. {Res Dev Disabil};2013 (Apr 11);34(6):1897-1905.
The aim of this study was to investigate orthostatic reactions in females with Rett syndrome (RTT), and also whether the severity of the syndrome had an impact on autonomic reactions. Based on signs of impaired function of the central autonomic system found in RTT, it could be suspected that orthostatic reactions were affected. The orthostatic reactions in 21 females with RTT and 14 normally developed females matched by age were investigated when they rose from a sitting position, and during standing for 3min. Reactions of the heart, the blood pressure and the time for recovery of systolic blood pressure, were studied in real time, heartbeat by heartbeat, simultaneously. There was no difference between participants with RTT and the normally developed controls regarding general orthostatic reactions (heart rate, systolic and diastolic blood pressure, and mean arterial pressure) when getting up from a sitting position, and when standing erect for 3min. In the specific immediate response by the heart to standing up, the 30:15 ratio, significantly lower values were found for females with RTT. In the RTT group, the maximum fall of systolic blood pressure showed a tendency to a larger decrease, and the initial decrease in systolic blood pressure was significantly faster. The time for recovery of systolic blood pressure from standing erect did not differ between groups. At baseline the females with RTT had significantly lower systolic blood pressure and a tendency to a higher heart rate. The results do not indicate any autonomic limitations for people with RTT in getting up from a sitting position and standing. The participants with RTT had normal orthostatic reactions indicated by the heart and blood pressure responses when standing erect for 3min. A faster initial drop in systolic blood pressure in people with RTT was notable.
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5. Leigh MJ, Nguyen DV, Mu Y, Winarni TI, Schneider A, Chechi T, Polussa J, Doucet P, Tassone F, Rivera SM, Hessl D, Hagerman RJ. {{A Randomized Double-Blind, Placebo-Controlled Trial of Minocycline in Children and Adolescents with Fragile X Syndrome}}. {J Dev Behav Pediatr};2013 (Apr);34(3):147-155.
OBJECTIVE:: Minocycline rescued synaptic abnormalities and improved behavior in the fragile X mouse model. Previous open-label human studies demonstrated benefits in individuals with fragile X syndrome (FXS); however, its efficacy in patients with FXS has not been assessed in a controlled trial. METHOD:: Randomized, double-blind, placebo-controlled, crossover trial in individuals with FXS, aged 3.5 years to 16 years (n = 55, mean age 9.2 [SD, 3.6] years). Participants were randomized to minocycline or placebo for 3 months and then switched to the other treatment. RESULTS:: Sixty-nine subjects were screened and 66 were randomized. Fifty-five subjects (83.3%) completed at least the first period and 48 (72.7%) completed the full trial. Intention-to-treat analysis demonstrated significantly greater improvements in one primary outcome, Clinical Global Impression Scale-Improvement after minocycline compared with placebo (2.49 +/- 0.13 and 2.97 +/- 0.13, respectively, p = .0173) and greater improvement in ad hoc analysis of anxiety and mood-related behaviors on the Visual Analog Scale (minocycline: 5.26 cm +/- 0.46 cm, placebo: 4.05 cm +/- 0.46 cm; p = .0488). Side effects were not significantly different during the minocycline and placebo treatments. No serious adverse events occurred on minocycline. Results may be potentially biased by study design weaknesses, including unblinding of subjects when they completed the study, drug-related side effects unblinding, and preliminary efficacy analysis results known to investigators. CONCLUSIONS:: Minocycline treatment for 3 months in children with FXS resulted in greater global improvement than placebo. Treatment for 3 months appears safe; however, longer trials are indicated to further assess benefits, side effects, and factors associated with a clinical response to minocycline.
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6. Miller VM, Gupta D, Neu N, Cotroneo A, Boulay CB, Seegal RF. {{Novel inter-hemispheric white matter connectivity in the BTBR mouse model of autism}}. {Brain Res};2013 (Apr 6)
Alterations in the volume, density, connectivity and functional activation of white matter tracts are reported in some individuals with autism and may contribute to their abnormal behaviors. The BTBR (BTBR T+tf/J) inbred strain of mouse, is used to model facets of autism because they develop low social behaviors, stereotypical and immune changes similar to those found in people with autism. Previously, it was thought a total absence of corpus callosal interhemispheric connective tissues in the BTBR mice may underlie their abnormal behaviors. However, postnatal lesions of the corpus callosum do not precipitate social behavioral problems in other strains of mice suggesting a flaw in this theory. In this study we used digital pathological methods to compare subcortical white matter connective tracts in the BTBR strain of mice with those found in the C57Bl/6 mouse and those reported in a standardized mouse brain atlas. We report, for the first time, a novel connective subcortical interhemispheric bridge of tissue in the posterior, but not anterior, cerebrum of the BTBR mouse. These novel connective tissues are comprised of myelinated fibers, with reduced myelin basic protein levels (MBP) compared to levels in the C57Bl/6 mouse. We used electrophysiological analysis and found increased corpus callosum connectivity in the posterior hemispheres of the BTBR strain compared with the anterior hemispheres. The conduction velocity was slower than that reported in normal mice. This study shows there is novel abnormal interhemispheric connectivity in the BTBR strain of mice, which may contribute to their behavioral abnormalities.
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7. Pellicano E, Rhodes G, Calder AJ. {{Reduced gaze aftereffects are related to difficulties categorizing gaze direction in autism}}. {Neuropsychologia};2013 (Apr 11)
Perceptual mechanisms are generally flexible or « adaptive », as evidenced by perceptual aftereffects: distortions that arise following exposure to a stimulus. We examined whether adaptive mechanisms for coding gaze direction are atypical in children diagnosed with an autism spectrum condition. Twenty-four typical children and 24 children with autism, of similar age and ability, were administered a developmentally sensitive eye-gaze adaptation task. In the pre-adaptation phase, children judged whether target faces showing subtle deviations in eye-gaze direction were looking leftwards, rightwards or straight-ahead. Next, children were adapted to faces gazing in one consistent direction (25 degrees leftwards/rightwards) before categorizing the direction of the target faces again. Children with autism showed difficulties in judging whether subtle deviations in gaze were directed to the left, right or straight-ahead relative to typical children. Although adaptation to leftward or rightward gaze resulted in reduced sensitivity to gaze on the adapted side for both groups, the aftereffect was significantly reduced in children with autism. Furthermore, the magnitude of children’s gaze aftereffects was positively related to their ability to categorize gaze direction. These results show that the mechanisms coding gaze are less flexible in autism and offer a potential new explanation for these children’s difficulties discriminating subtle deviations in gaze direction.
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8. Pini G, Bigoni S, Engerstrom IW, Calabrese O, Felloni B, Scusa MF, Di Marco P, Borelli P, Bonuccelli U, Julu PO, Nielsen JB, Morin B, Hansen S, Gobbi G, Visconti P, Pintaudi M, Edvige V, Romanelli A, Bianchi F, Casarano M, Battini R, Cioni G, Ariani F, Renieri A, Benincasa A, Delamont RS, Zappella M. {{Variant of Rett Syndrome and CDKL5 Gene: Clinical and Autonomic Description of 10 Cases}}. {Neuropediatrics};2013 (Apr 11)
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9. Riva D, Annunziata S, Contarino V, Erbetta A, Aquino D, Bulgheroni S. {{Gray Matter Reduction in the Vermis and CRUS-II Is Associated with Social and Interaction Deficits in Low-Functioning Children with Autistic Spectrum Disorders: a VBM-DARTEL Study}}. {Cerebellum};2013 (Apr 10)
Voxel-based morphometry (VBM) studies have reported abnormalities in brain regions involved in functions that are commonly impaired in autism spectrum disorders (ASD). However, little is known about brain structure anomalies in low-functioning (LF) young children with ASD. A VBM analysis was carried out to assess brain regions involved in ASD LF children, and a multiple regression analysis was used to examine the relationship between regional volume changes and autism symptom measures. Twenty-six LF ASD children (2-10 years) were compared with 21 controls. A VBM-Diffeomorphic Anatomical Registration analysis using Exponentiated Lie algebra (DARTEL) was used to evaluate gray matter (GM) and white matter alterations, covaried with Intelligence Quotient, age, and total brain volume. The resulting altered regions were correlated with Autism Diagnostic Interview (ADI)-Revised and Autism Diagnostic Observation Schedule (ADOS)-Generic scores. GM bilateral reduction was noted in the cerebellum (Crus II and vermis) and in the hippocampi in ASD group. GM reduction was also detected in the inferior and superior frontal gyri, in the occipital medial and superior gyri, and in the inferior temporal gyrus of the left cerebral hemisphere. In the right hemisphere, GM reduction was found in the post-central cortex and in the occipital inferior gyrus. Multiple regression analysis showed a correlation between alterations in GM volume in the cerebellum (Crus II and vermis) and ADI-communication and ADOS-total (communication and interaction) scores. These findings seem to confirm that the cerebellum is involved in integrating and regulating emotional and cognitive functions which are impaired in ASD.
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10. Stein TP, Schluter MD, Steer RA, Ming X. {{Autism and Phthalate Metabolite Glucuronidation}}. {J Autism Dev Disord};2013 (Apr 11)
Exposure to environmental chemicals may precipitate autism spectrum disorders (ASD) in genetically susceptible children. Differences in the efficiency of the glucuronidation process may substantially modulate substrate concentrations and effects. To determine whether the efficiency of this pathway is compromised in children with ASD, we measured the efficiency of glucuronidation for a series of metabolites derived from the commonly used plasticizer, diethylhexyl phthalate. Spot urines were collected and analyzed for the fraction of each metabolite conjugated by isotope dilution-liquid chromatography mass spectrometry-mass spectrometry. The degree of glucuronidation was lower with the ASD group. The glucuronidation pathway may differ in some children with ASD.
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11. Sun X, Allison C, Matthews FE, Sharp SJ, Auyeung B, Baron-Cohen S, Brayne C. {{Prevalence of autism in mainland China, Hong Kong and Taiwan: a systematic review and meta-analysis}}. {Mol Autism};2013 (Apr 9);4(1):7.
BACKGROUND: The prevalence of autism spectrum conditions (ASC) has been reported to be 1% in developed countries, but few data are available from mainland China, Hong Kong and Taiwan. This study will synthesize evidence relating to the prevalence of ASC in these areas and assess the effects of research methodology on prevalence estimates. METHODS: Systematic literature searches were conducted in PubMed, Web of Knowledge, China Web of Knowledge and Weipu databases, as well as relevant papers published from 1987 to 2011, reporting prevalence estimates of ASC or childhood autism in mainland China, Hong Kong and Taiwan. Summary estimates of prevalence were calculated with a random effects model. The effects of research methodology on the prevalence estimates were assessed using a meta-regression model. RESULTS: There were 25 studies eligible for review, 18 of which were suitable for inclusion in a meta-analysis. Pooled prevalence of childhood autism was 11.8 per 10,000 individuals (95% confidence interval (CI): 8.2, 15.3) in mainland China. Pooled prevalence of ASC was 26.6 per 10,000 (95% CI: 18.5, 34.6) in three areas. Substantial heterogeneity was identified between studies (I2>75%). The prevalence estimate of childhood autism was most strongly associated with the choice of screening instrument. After adjustment for age group, the odds ratio for prevalence estimates when using the Autism Behavior Checklist (ABC) as the screening instrument compared with those using the Clancy Autism Behavior Scale (CABS) was 0.29 (95% CI: 0.12, 0.69), and 1.79 (95% CI: 0.70, 4.55; P= 0.20) when using the Checklist for Autism in Toddlers (CHAT) compared to the CABS. CONCLUSIONS: The available studies focused mainly on childhood autism but not the whole spectrum. The prevalence estimates are lower than estimates from developed countries. Studies using more recently developed screening instruments reported higher prevalence than older ones. However, available studies have methodological weaknesses and therefore these results lack comparability with those from developed countries. Our findings indicate a potential under-diagnosis and under-detection of ASC in mainland China, Hong Kong and Taiwan, and a need to adopt more advanced methods for research of ASC in these areas.
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12. Theoharides TC, Asadi S, Patel AB. {{Focal brain inflammation and autism}}. {J Neuroinflammation};2013;10:46.
Increasing evidence indicates that brain inflammation is involved in the pathogenesis of neuropsychiatric diseases. Autism spectrum disorders (ASD) are characterized by social and learning disabilities that affect as many as 1/80 children in the USA. There is still no definitive pathogenesis or reliable biomarkers for ASD, thus significantly curtailing the development of effective therapies. Many children with ASD regress at about age 3 years, often after a specific event such as reaction to vaccination, infection, stress or trauma implying some epigenetic triggers, and may constitute a distinct phenotype. ASD children respond disproportionally to stress and are also affected by food and skin allergies. Corticotropin-releasing hormone (CRH) is secreted under stress and together with neurotensin (NT) stimulates mast cells and microglia resulting in focal brain inflammation and neurotoxicity. NT is significantly increased in serum of ASD children along with mitochondrial DNA (mtDNA). NT stimulates mast cell secretion of mtDNA that is misconstrued as an innate pathogen triggering an auto-inflammatory response. The phosphatase and tensin homolog (PTEN) gene mutation, associated with the higher risk of ASD, which leads to hyper-active mammalian target of rapamycin (mTOR) signalling that is crucial for cellular homeostasis. CRH, NT and environmental triggers could hyperstimulate the already activated mTOR, as well as stimulate mast cell and microglia activation and proliferation. The natural flavonoid luteolin inhibits mTOR, mast cells and microglia and could have a significant benefit in ASD.
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13. Zur O, Ronen A, Melzer I, Carmeli E. {{Vestibulo-ocular response and balance control in children and young adults with mild-to-moderate intellectual and developmental disability: A pilot study}}. {Res Dev Disabil};2013 (Apr 11);34(6):1951-1957.
The vestibulo-ocular response (VOR) may not be fully developed in children with an intellectual and developmental disability (IDD). This study aimed to identify the presence of VOR deficit in children and young adults with unspecified mild-to-moderate intellectual and developmental disability and its effect on balance control. Twenty-one children and young adults with IDD ranging in age from 8 to 22 years (mean 17.5+/-3.9 years) were included in the study. The VOR was evaluated with the Head Impulse Test and the Static and Dynamic Visual Acuity Test (S&D-VAT). Postural stability was measured in an upright standing position by the Clinical Test for Sensory Interaction in Balance (CTSIB), single leg stance (SLS) during eyes open and eyes closed, and Romberg stance under eyes open and eyes closed conditions using a force platform. Reduced vestibulo-ocular responses were found in 13 of 21 (62%) participants who were able to complete testing. In the fifth condition of the CTSIB (standing on foam with eyes closed), those without VOR deficit were able to maintain balance longer than those with VOR deficit (29s [median 30] vs. 12s [median 7.3], respectively; p=0.03). The study demonstrates potential effects of VOR deficit in children and young adults with IDD and some significant differences in balance control between those with and without a VOR deficit. VOR function in children and young adults with IDD should be routinely tested to enable early detection of deficits.
