1. Bakare MO, Munir KM, Kinney DK. {{Associations of hypomelanotic skin disorders with autism: Do they reflect the effects of genetic mutations and epigenetic factors on vitamin-D metabolism in individuals at risk for autism?}}. {Hypothesis (Macon)};2011 (Apr 16);9(1):e2.
Vitamin D is crucial for full functioning in many genes, and vitamin-D deficiency interferes with many processes, including brain development and DNA repair. Several lines of evidence suggest that prenatal and early postnatal vitamin-D deficiency increases risk for autism, probably through multiple effects that include impaired brain development and increased de novo mutations. High rates of autism in several genetically based hypomelanotic skin disorders present a puzzle, because ultraviolet-B (UVB) radiation acting on skin is the major natural source of vitamin D, and lighter skin, which increases UVB penetration, helps protect against vitamin-D deficiency, especially at higher latitudes. Understanding autism’s association with hypomelanosis may elucidate autism’s etiology. We consider two hypotheses that may help explain autism’s association with hypomelanotic disorders. Hypothesis 1) Because genetic and epigenetic variants that produce hypomelanotic conditions may help protect against vitamin-D deficiency, especially at higher latitudes, these variants may tend to decrease mortality – and increase the fertility – of individuals who also carry genetic or epigenetic factors that increase vulnerability to autism. Hypothesis 2) Children with hypomelanotic conditions will be more likely to develop autism, because children’s photosensitivity and parental concerns about sunburn and skin cancer lead them to excessively reduce children’s sun exposure and resultant vitamin-D levels. One approach to testing these hypotheses would involve comparing the genomes, epigenetic markers, skin pigmentation, and serum and brain levels of the active form of vitamin D in autistic individuals, with and without co-morbid hypomelanoses, as well as in their relatives and controls. Because availability of UVB radiation varies widely around the world, epidemiological and genetic studies of the co-morbidity in different regions would provide complementary means of testing the hypotheses. If test results support either hypothesis, they will add important evidence for an etiologic role of vitamin-D deficiency in autism, as well as supporting investigation of whether vitamin-D enhancement may aid treatment and prevention of autism.
2. Bie B, Tang L. {{Representation of Autism in Leading Newspapers in China: A Content Analysis}}. {Health Commun};2014 (Jul 29):1-10.
The public’s lack of understanding and the public’s misconceptions about autism in China contribute to the underdiagnosis and undertreatment of the disorder and the stigma associated with it. Mass media are the primary channel through which people learn about autism. This article examines how leading newspapers in China covered autism in the 10-year period of 2003 through 2012 through a framing analysis. It finds that while autism has received increased media attention, it is increasingly framed as a family problem-family members are cited or quoted more than any other sources and the responsibility of dealing with autism is ultimately assigned to families. Autistic people are largely silenced unless they are autistic savants with special talents. The use of the scientific discourse and the human-interest discourse both decrease over time in percentage, while the use of other discourses such as the public relations discourse becomes more dominant.
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3. Chang YS, Owen JP, Desai SS, Hill SS, Arnett AB, Harris J, Marco EJ, Mukherjee P. {{Autism and sensory processing disorders: shared white matter disruption in sensory pathways but divergent connectivity in social-emotional pathways}}. {PLoS One};2014;9(7):e103038.
Over 90% of children with Autism Spectrum Disorders (ASD) demonstrate atypical sensory behaviors. In fact, hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment is now included in the DSM-5 diagnostic criteria. However, there are children with sensory processing differences who do not meet an ASD diagnosis but do show atypical sensory behaviors to the same or greater degree as ASD children. We previously demonstrated that children with Sensory Processing Disorders (SPD) have impaired white matter microstructure, and that this white matter microstructural pathology correlates with atypical sensory behavior. In this study, we use diffusion tensor imaging (DTI) fiber tractography to evaluate the structural connectivity of specific white matter tracts in boys with ASD (n = 15) and boys with SPD (n = 16), relative to typically developing children (n = 23). We define white matter tracts using probabilistic streamline tractography and assess the strength of tract connectivity using mean fractional anisotropy. Both the SPD and ASD cohorts demonstrate decreased connectivity relative to controls in parieto-occipital tracts involved in sensory perception and multisensory integration. However, the ASD group alone shows impaired connectivity, relative to controls, in temporal tracts thought to subserve social-emotional processing. In addition to these group difference analyses, we take a dimensional approach to assessing the relationship between white matter connectivity and participant function. These correlational analyses reveal significant associations of white matter connectivity with auditory processing, working memory, social skills, and inattention across our three study groups. These findings help elucidate the roles of specific neural circuits in neurodevelopmental disorders, and begin to explore the dimensional relationship between critical cognitive functions and structural connectivity across affected and unaffected children.
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4. Cooper M, Thapar A, Jones DK. {{Erratum to: White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder}}. {J Autism Dev Disord};2014 (Jul 30)
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5. Elsabbagh M, Bruno R, Wan MW, Charman T, Johnson MH, Green J. {{Infant Neural Sensitivity to Dynamic Eye Gaze Relates to Quality of Parent-Infant Interaction at 7-Months in Infants at Risk for Autism}}. {J Autism Dev Disord};2014 (Jul 30)
Links between brain function measures and quality of parent-child interactions within the early developmental period have been investigated in typical and atypical development. We examined such links in a group of 104 infants with and without a family history for autism in the first year of life. Our findings suggest robust associations between event related potential responses to eye gaze and observed parent-infant interaction measures. In both groups, infants with more positive affect exhibit stronger differentiation to gaze stimuli. This association was observed with the earlier P100 waveform component in the control group but with the later P400 component in infants at-risk. These exploratory findings are critical in paving the way for a better understanding of how infant laboratory measures may relate to overt behavior and how both can be combined in the context of predicting risk or clinical diagnosis in toddlerhood.
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6. Hirvikoski T, Blomqvist M. {{High self-perceived stress and poor coping in intellectually able adults with autism spectrum disorder}}. {Autism};2014 (Jul 29)
Despite average intellectual capacity, autistic traits may complicate performance in many everyday situations, thus leading to stress. This study focuses on stress in everyday life in intellectually able adults with autism spectrum disorders. In total, 53 adults (25 with autism spectrum disorder and 28 typical adults from the general population) completed the Perceived Stress Scale. Autistic traits were assessed using the Autism Spectrum Quotient. Adults with autism spectrum disorder reported significantly higher subjective stress and poorer ability to cope with stress in everyday life, as compared to typical adults. Autistic traits were associated with both subjective stress/distress and coping in this cross-sectional series. The long-term consequences of chronic stress in everyday life, as well as treatment intervention focusing on stress and coping, should be addressed in future research as well as in the clinical management of intellectually able adults with autism spectrum disorder.
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7. Hodgetts S, Zwaigenbaum L, Nicholas D. {{Profile and predictors of service needs for families of children with autism spectrum disorders}}. {Autism};2014 (Jul 29)
PURPOSE: Increasing demand for autism services is straining service systems. Tailoring services to best meet families’ needs could improve their quality of life and decrease burden on the system. We explored overall, best, and worst met service needs, and predictors of those needs, for families of children with autism spectrum disorders. METHODS: Parents of 143 children with autism spectrum disorders (2-18 years) completed a survey including demographic and descriptive information, the Family Needs Survey-Revised, and an open-ended question about service needs. Descriptive statistics characterize the sample and determine the degree to which items were identified and met as needs. Predictors of total and unmet needs were modeled with regression or generalized linear model. Qualitative responses were thematically analyzed. RESULTS: The most frequently identified overall and unmet service needs were information on services, family support, and respite care. The funding and quality of professional support available were viewed positively. Decreased child’s age and income and being an older mother predicted more total needs. Having an older child or mother, lower income, and disruptive behaviors predicted more total unmet needs, yet only disruptive behaviors predicted proportional unmet need. Child’s language or intellectual abilities did not predict needs. CONCLUSION: Findings can help professionals, funders, and policy-makers tailor services to best meet families’ needs.
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8. Lepage JF, Lortie M, Deal CL, Theoret H. {{Empathy, autistic traits, and motor resonance in adults with Turner syndrome}}. {Soc Neurosci};2014 (Jul 31):1-9.
Turner syndrome is a genetic condition resulting from the partial or complete absence of an X-chromosome in phenotypic females. Individuals with Turner syndrome often display social difficulties that are reminiscent of those associated with autistic spectrum disorders (ASD), conditions associated with empathy and mirror-neuron system (MNS) deficits. The goal of the present study was (1) to investigate the extent to which adults with Turner syndrome display autistic and empathic traits, and (2) to probe the integrity of the MNS in this neurogenetic disorder. Sixteen individuals with Turner syndrome and 16 age-, sex-, and IQ-matched controls took part in a neuropsychological assessment where the Weschler Abbreviated Scale of Intelligence, the Autism Spectrum Quotient and the Empathy Quotient were administered. Functioning of the MNS was assessed by measuring motor cortex activity with transcranial magnetic stimulation during an action-observation task. Results show that individuals with Turner syndrome do not differ significantly from controls regarding autistic or empathic traits, and present normal functioning of the MNS during action observation. Correlational analysis showed a significant positive relationship between scores on the Empathy Quotient and motor facilitation during action observation, bringing further support to the hypothesis that MNS activity is related to sociocognitive competence.
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9. Naganathan AN, Munoz V. {{Thermodynamics of Downhill Folding: Multi-Probe Analysis of PDD, a Protein that Folds Over a Marginal Free Energy Barrier}}. {J Phys Chem B};2014 (Jul 31);118(30):8982-8994.
Downhill folding proteins fold in microseconds by crossing a very low or no free energy barrier (<3 RT), and exhibit a complex unfolding behavior in equilibrium. Such unfolding complexity is due to the weak thermodynamic coupling that exists between the various structural segments of these proteins, and it is manifested in unfolding curves that differ depending on the structural probe employed to monitor the process. Probe-dependent unfolding has important practical implications because it permits one to investigate the folding energy landscape in detail using multiprobe thermodynamic experiments. This type of thermodynamic behavior has been investigated in depth on the protein BBL, an example of extreme (one-state) downhill folding in which there is no free energy barrier at any condition, including the denaturation midpoint. However, an open question is, to what extent is such thermodynamic behavior observed on less extreme downhill folders? Here we perform a multiprobe spectroscopic characterization of the microsecond folder PDD, a structural and functional homologue of BBL that folds within the downhill regime, but is not an example of one-state downhill folding; rather at the denaturation midpoint PDD folds by crossing an incipient free energy barrier. Model-free analysis of the unfolding curves from four different spectroscopic probes together with differential scanning calorimetry reveals a dispersion of approximately 9 K in the apparent melting temperature and also marked differences in unfolding broadness (from approximately 50 to approximately 130 kJ mol-1 when analyzed with a two-state model), confirming that such properties are also observed on less extreme downhill folders. We subsequently perform a global quantitative analysis of the unfolding data of PDD using the same ME statistical mechanical model that was used before for the BBL domain. The analysis shows that this simple model captures all of the features observed on the unfolding of PDD (i.e., the intensity and temperature dependence of the different spectroscopic signals). From the model we estimate a free energy landscape for PDD in which the maximal thermodynamic barrier (i.e., at the denaturation midpoint) is only approximately 0.5 RT, consistent with previous independent estimates. Our results highlight that multiprobe unfolding experiments in equilibrium combined with statistical mechanical modeling provide important insights into the structural events that take place during the unfolding process of downhill proteins, and thus effectively probe the free energy landscape of these proteins.
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10. Uddin LQ, Supekar K, Lynch CJ, Cheng KM, Odriozola P, Barth ME, Phillips J, Feinstein C, Abrams DA, Menon V. {{Brain State Differentiation and Behavioral Inflexibility in Autismdagger}}. {Cereb Cortex};2014 (Jul 29)
Autism spectrum disorders (ASDs) are characterized by social impairments alongside cognitive and behavioral inflexibility. While social deficits in ASDs have extensively been characterized, the neurobiological basis of inflexibility and its relation to core clinical symptoms of the disorder are unknown. We acquired functional neuroimaging data from 2 cohorts, each consisting of 17 children with ASDs and 17 age- and IQ-matched typically developing (TD) children, during stimulus-evoked brain states involving performance of social attention and numerical problem solving tasks, as well as during intrinsic, resting brain states. Effective connectivity between key nodes of the salience network, default mode network, and central executive network was used to obtain indices of functional organization across evoked and intrinsic brain states. In both cohorts examined, a machine learning algorithm was able to discriminate intrinsic (resting) and evoked (task) functional brain network configurations more accurately in TD children than in children with ASD. Brain state discriminability was related to severity of restricted and repetitive behaviors, indicating that weak modulation of brain states may contribute to behavioral inflexibility in ASD. These findings provide novel evidence for a potential link between neurophysiological inflexibility and core symptoms of this complex neurodevelopmental disorder.
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11. Yang W, Pan H. {{Regulation mechanism and research progress of MeCP2 in Rett syndrome}}. {Yi Chuan};2014 (Jul 20);36(7):625-630.
Rett syndrome (RTT) is an X-linked neurodevelopmental disease accountable for some of the severe mental retardation of females. Mutations in the gene encoding mythyl-CpG-binding protein 2, MeCP2, which acts as a suppressor of gene expression, are the primary genetic pathological change of RTT. Insufficient binding of MeCP2 with methylated DNA disrupts the proper expression of target genes and results in brain dysfunction. Currently, the proper role MeCP2 played in the process of brain development and the occurrence of RTT remain elusive. In this review, we summarize both the MECP2 gene and MeCP2 protein, with highlight upon their structures, functions and more importantly their regulatory mechanisms at the molecular level so as to elucidate the mechanisms underlying the pathogenesis of RTT.
