Pubmed du 12/08/14

Pubmed du jour

2014-08-12 12:03:50

1. {{Correction: A Reciprocal Model of Face Recognition and Autistic Traits: Evidence from an Individual Differences Perspective}}. {PLoS One};2014;9(8):e105669.

[This corrects the article DOI: 10.1371/journal..].

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2. Barbalat G, Leboyer M, Zalla T. {{A specific impairment in cognitive control in individuals with high-functioning autism}}. {J Psychiatr Res};2014 (Jul 23)
Although it is largely demonstrated that Autism Spectrum Disorders (ASDs) are characterized by executive dysfunctions, little is known about the fine-grained levels of this impairment. Here, we investigated the hierarchical architecture of control modules in autism using an experimental paradigm based upon a multistage model of executive functions. This model postulates that executive functions are hierarchically organized as a cascade of three different control processes, which are implemented according to information conveyed by sensory signals (sensory control), the immediate perceptual context (contextual control), and the temporal episode in which stimuli occur (episodic control). Sixteen high-functioning adults with autism or Asperger Syndrome (HFA/AS) and sixteen matched comparison participants took part in two distinct visuo-motor association experiments designed to separately vary the demands of sensory and episodic controls (first experiment) and contextual and episodic controls (second experiment). Participants with HFA/AS demonstrated no significant differences in performances with comparison participants when they had to control sensory or contextual information. However, they showed decreased accuracy when having to control information related to episodic signals. Remarkably, performances in episodic control were associated to the autism spectrum quotient in both groups, suggesting that this episodic control impairment might be at the core of ASDs. Those results plead for a specific, rather than generalised, deficit in executive functions in autism. Our study contributes to a better understanding of the impaired cognitive processes that are unique to autism and warrants confirmation using other models of executive functions.

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3. Baxter AJ, Brugha TS, Erskine HE, Scheurer RW, Vos T, Scott JG. {{The epidemiology and global burden of autism spectrum disorders}}. {Psychol Med};2014 (Aug 11):1-13.

BACKGROUND: Autism spectrum disorders (ASDs) are persistent disabling neurodevelopmental disorders clinically evident from early childhood. For the first time, the burden of ASDs has been estimated for the Global Burden of Disease Study 2010 (GBD 2010). The aims of this study were to develop global and regional prevalence models and estimate the global burden of disease of ASDs. Method A systematic review was conducted for epidemiological data (prevalence, incidence, remission and mortality risk) of autistic disorder and other ASDs. Data were pooled using a Bayesian meta-regression approach while adjusting for between-study variance to derive prevalence models. Burden was calculated in terms of years lived with disability (YLDs) and disability-adjusted life-years (DALYs), which are reported here by world region for 1990 and 2010. RESULTS: In 2010 there were an estimated 52 million cases of ASDs, equating to a prevalence of 7.6 per 1000 or one in 132 persons. After accounting for methodological variations, there was no clear evidence of a change in prevalence for autistic disorder or other ASDs between 1990 and 2010. Worldwide, there was little regional variation in the prevalence of ASDs. Globally, autistic disorders accounted for more than 58 DALYs per 100000 population and other ASDs accounted for 53 DALYs per 100000. CONCLUSIONS: ASDs account for substantial health loss across the lifespan. Understanding the burden of ASDs is essential for effective policy making. An accurate epidemiological description of ASDs is needed to inform public health policy and to plan for education, housing and financial support services.

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4. Berman J, Liu S, Bloy L, Blaskey L, Roberts TP, Edgar JC. {{Alpha-to-Gamma Phase-amplitude Coupling Methods and Application to Autism Spectrum Disorder}}. {Brain Connect};2014 (Aug 10)
Adult studies have shown that a basic property of resting-state (RS) brain activity is the coupling of posterior alpha oscillations (alpha phase) to posterior gamma oscillations (gamma amplitude). The present study examined whether this basic RS process is present in children. Given reports of abnormal parietal-occipital RS alpha in children with autism spectrum disorder (ASD), the present study examined whether RS alpha-to-gamma phase-amplitude coupling (PAC) is disrupted in ASD. Simulations presented in this study showed limitations with traditional PAC analyses. In particular, to avoid false-positive PAC findings, simulations showed the need to use a unilateral passband to filter the upper frequency band as well as the need for longer epochs of data. For the human study, eyes-closed RS magnetoencephalography data were analyzed from 25 children with ASD and 18 typically developing (TD) children with at least 60 seconds of artifact free data. Source modeling provided continuous time course data at a midline parietal-occipital source for PAC analyses. Greater alpha-to-gamma PAC was observed in ASD than TD (p<0.005). Although children with ASD had higher PAC values, in both groups gamma activity increased at the peak of the alpha oscillation. In addition, an association between alpha power and alpha-to-gamma PAC was observed in both groups, although this relationship was stronger in ASD than TD (p <0.05). Present results demonstrated that although alpha-to-gamma PAC is present in children, this basic RS process is abnormal in children with ASD. Finally, simulations and the human data highlighted the need to consider the interplay between alpha power, epoch length, and choice of signal processing methods on PAC estimates.

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5. Brown CM, Austin DW, Busija L. {{Observable essential fatty acid deficiency markers and autism spectrum disorder}}. {Breastfeed Rev};2014 (Jul);22(2):21-26.

Autism Spectrum Disorder (ASD) has been associated with essential fatty acid (EFA) deficiencies, with some researchers theorising that dysregulation of phospholipid metabolism may form part of the biological basis for ASD. This pilot study compared observable signs of fatty acid status of 19 children with an ASD diagnosis to 23 of their typically developing siblings. A pregnancy, birth and breastfeeding history was also obtained from their parents, which included a measure of infant intake of fatty acid rich colostrum immediately post-partum. When considered within their family group, those infants not breastfed (with colostrum) within the first hour of life and who had a history of fatty acid deficiency symptoms were more likely to have an ASD diagnosis. Other variables such as formula use, duration of breastfeeding, gestational age and Apgar scores were not associated with group membership. The results of this study are consistent with previous research showing a relationship between fatty acid metabolism, breastfeeding and ASD such that early infant feeding practices and the influence this has on the fatty acid metabolism of the child may be a risk factor for ASD.

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6. Deoni SC, Zinkstok JR, Daly E, Ecker C, Williams SC, Murphy DG. {{White-matter relaxation time and myelin water fraction differences in young adults with autism}}. {Psychol Med};2014 (Aug 11):1-11.

BACKGROUND: Increasing evidence suggests that autism is associated with abnormal white-matter (WM) anatomy and impaired brain ‘connectivity’. While myelin plays a critical role in synchronized brain communication, its aetiological role in autistic symptoms has only been indirectly addressed by WM volumetric, relaxometry and diffusion tensor imaging studies. A potentially more specific measure of myelin content, termed myelin water fraction (MWF), could provide improved sensitivity to myelin alteration in autism. METHOD: We performed a cross-sectional imaging study that compared 14 individuals with autism and 14 age- and IQ-matched controls. T 1 relaxation times (T 1), T 2 relaxation times (T 2) and MWF values were compared between autistic subjects, diagnosed using the Autism Diagnostic Interview – Revised (ADI-R), with current symptoms assessed using the Autism Diagnostic Observation Schedule (ADOS) and typical healthy controls. Correlations between T 1, T 2 and MWF values with clinical measures [ADI-R, ADOS, and the Autism Quotient (AQ)] were also assessed. RESULTS: Individuals with autism showed widespread WM T 1 and MWF differences compared to typical controls. Within autistic individuals, worse current social interaction skill as measured by the ADOS was related to reduced MWF although not T 1. No significant differences or correlations with symptoms were observed with respect to T 2. CONCLUSIONS: Autistic individuals have significantly lower global MWF and higher T 1, suggesting widespread alteration in tissue microstructure and biochemistry. Areas of difference, including thalamic projections, cerebellum and cingulum, have previously been implicated in the disorder; however, this is the first study to specifically indicate myelin alteration in these regions.

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7. Dubischar-Krivec AM, Bolte S, Braun C, Poustka F, Birbaumer N, Neumann N. {{Neural mechanisms of savant calendar calculating in autism: An MEG-study of few single cases}}. {Brain Cogn};2014 (Aug 7);90C:157-164.

This study contrasted the neurological correlates of calendar calculating (CC) between those individuals with autism spectrum disorder (ASD) and typically developing individuals. CC is the ability to correctly and quickly state the day of the week of a given date. Using magnetoencephalography (MEG), we presented 126 calendar tasks with dates of the present, past, and future. Event-related magnetic fields (ERF) of 3000ms duration and brain activation patterns were compared in three savant calendar calculators with ASD (ASDCC) and three typically developing calendar calculators (TYPCC). ASDCC outperformed TYPCC in correct responses, but not in answering speed. Comparing amplitudes of their ERFs, there was a main effect of group between 1000 and 3000ms, but no further effects of hemisphere or sensor location. We conducted CLARA source analysis across the entire CC period in each individual. Both ASDCC and TYPCC exhibited activation maxima in prefrontal areas including the insulae and the left superior temporal gyrus. This is in accordance with verbal fact retrieval and working memory as well as monitoring and coordination processes. In ASDCC, additional activation sites at the right superior occipital gyrus, the right precuneus, and the right putamen point to visual-spatial strategies and are in line with the preference of autistic individuals for engaging posterior regions relatively more strongly in various reasoning and problem solving tasks.

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8. Elliott SJ, Fitzsimons L. {{Modified CBT for Treatment of OCD in a 7-Year-Old Boy With ASD-A Case Report}}. {J Child Adolesc Psychiatr Nurs};2014 (Aug);27(3):156-159.

Children and adolescents with autism spectrum disorder (ASD) frequently experience obsessive-compulsive disorder (OCD). Cognitive behavioral therapy (CBT) is recommended for OCD but may need modification in children and adolescents with ASD because of cognitive differences, but guidance for therapists planning CBT for OCD in young people with ASD is sparse. This report discusses syndromes of OCD and ASD and their overlapping clinical features and etiologies, difficulties in applying CBT in the ASD population, and relevant literature. We present a case report on CBT treatment of a 7-year-old boy with ASD and OCD and modifications to CBT that were helpful.

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9. Hollin GJ, Pilnick A. {{Infancy, autism, and the emergence of a socially disordered body}}. {Soc Sci Med};2014 (Jul 22)
Twenty academic psychologists and neuroscientists, with an interest in autism and based within the United Kingdom, were interviewed between 2012 and 2013 on a variety of topics related to the condition. Within these qualitative interviews researchers often argued that there had been a ‘turn to infancy’ since the beginning of the 21st century with focus moving away from the high functioning adolescent and towards the pre-diagnostic infant deemed to be ‘at risk’ of autism. The archetypal research of this type is the ‘infant sibs’ study whereby infants with an elder sibling already diagnosed with autism are subjected to a range of tests, the results of which are examined only once it becomes apparent whether that infant has autism. It is claimed in this paper that the turn to infancy has been facilitated by two phenomena; the autism epidemic of the 1990s and the emergence of various methodological techniques, largely although not exclusively based within neuroscience, which seek to examine social disorder in the absence of comprehension or engagement on the part of the participant: these are experiments done to participants rather than with them. Interviewees claimed that these novel methods allowed researchers to see a ‘real’ autism that lay ‘behind’ methodology. That claim is disputed here and instead it is argued that these emerging methodologies other various phenomena, reorienting the social abnormality believed typical of autism away from language and meaning and towards the body. The paper concludes by suggesting that an attempt to draw comparisons between the symptoms of autism in infant populations and adults with the condition inevitably leads to a somaticisation of autism.

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10. Kohls G, Yerys BE, Schultz RT. {{Striatal development in autism: repetitive behaviors and the reward circuitry}}. {Biol Psychiatry};2014 (Sep 1);76(5):358-359.

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11. Mayer JL, Hannent I, Heaton PF. {{Mapping the Developmental Trajectory and Correlates of Enhanced Pitch Perception on Speech Processing in Adults with ASD}}. {J Autism Dev Disord};2014 (Aug 9)
Whilst enhanced perception has been widely reported in individuals with Autism Spectrum Disorders (ASDs), relatively little is known about the developmental trajectory and impact of atypical auditory processing on speech perception in intellectually high-functioning adults with ASD. This paper presents data on perception of complex tones and speech pitch in adult participants with high-functioning ASD and typical development, and compares these with pre-existing data using the same paradigm with groups of children and adolescents with and without ASD. As perceptual processing abnormalities are likely to influence behavioural performance, regression analyses were carried out on the adult data set. The findings revealed markedly different pitch discrimination trajectories and language correlates across diagnostic groups. While pitch discrimination increased with age and correlated with receptive vocabulary in groups without ASD, it was enhanced in childhood and stable across development in ASD. Pitch discrimination scores did not correlate with receptive vocabulary scores in the ASD group and for adults with ASD superior pitch perception was associated with sensory atypicalities and diagnostic measures of symptom severity. We conclude that the development of pitch discrimination, and its associated mechanisms markedly distinguish those with and without ASD.

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12. Muller M, Can K. {{Aberrant redox homoeostasis and mitochondrial dysfunction in Rett syndrome}}. {Biochem Soc Trans};2014 (Aug 1);42(4):959-964.

RTT (Rett syndrome) is a severe progressive neurodevelopmental disorder with a monogenetic cause, but complex and multifaceted clinical appearance. Compelling evidence suggests that mitochondrial alterations and aberrant redox homoeostasis result in oxidative challenge. Yet, compared with other severe neuropathologies, RTT is not associated with marked neurodegeneration, but rather a chemical imbalance and miscommunication of neuronal elements. Different pharmacotherapies mediate partial improvement of conditions in RTT, and also antioxidants or compounds improving mitochondrial function may be of potential merit. In the present paper, we summarize findings from patients and transgenic mice that point towards the nature of RTT as a mitochondrial disease. Also, open questions are addressed that require clarification to fully understand and successfully target the associated cellular redox imbalance.

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13. Prottengeier J, Munster T, Pohmer S, Schmidt J. {{Anaesthesia and orphan disease: fragile X syndrome (Martin-Bell syndrome)}}. {Eur J Anaesthesiol};2014 (Aug 7)

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14. Samsam M, Ahangari R, Naser SA. {{Pathophysiology of autism spectrum disorders: Revisiting gastrointestinal involvement and immune imbalance}}. {World J Gastroenterol};2014 (Aug 7);20(29):9942-9951.

Autism spectrum disorders (ASD) comprise a group of neurodevelopmental abnormalities that begin in early childhood and are characterized by impairment of social communication and behavioral problems including restricted interests and repetitive behaviors. Several genes have been implicated in the pathogenesis of ASD, most of them are involved in neuronal synaptogenesis. A number of environmental factors and associated conditions such as gastrointestinal (GI) abnormalities and immune imbalance have been linked to the pathophysiology of ASD. According to the March 2012 report released by United States Centers for Disease Control and Prevention, the prevalence of ASD has sharply increased during the recent years and one out of 88 children suffers now from ASD symptoms. Although there is a strong genetic base for the disease, several associated factors could have a direct link to the pathogenesis of ASD or act as modifiers of the genes thus aggravating the initial problem. Many children suffering from ASD have GI problems such as abdominal pain, chronic diarrhea, constipation, vomiting, gastroesophageal reflux, and intestinal infections. A number of studies focusing on the intestinal mucosa, its permeability, abnormal gut development, leaky gut, and other GI problem raised many questions but studies were somehow inconclusive and an expert panel of American Academy of Pediatrics has strongly recommended further investigation in these areas. GI tract has a direct connection with the immune system and an imbalanced immune response is usually seen in ASD children. Maternal infection or autoimmune diseases have been suspected. Activation of the immune system during early development may have deleterious effect on various organs including the nervous system. In this review we revisited briefly the GI and immune system abnormalities and neuropeptide imbalance and their role in the pathophysiology of ASD and discussed some future research directions.

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15. Schenkelberg MA, Rosenkranz RR, Milliken GA, Dzewaltowski DA. {{Social Environmental Influences on Physical Activity of Children With Autism Spectrum Disorders}}. {J Phys Act Health};2014 (Aug 7)
BACKGROUND: Children with Autism Spectrum Disorders (ASD) may be at greater risk for not meeting physical activity (PA) guidelines than neurotypical children (NT). The purpose of this study was to explore setting (free play versus organized) and social group composition influences on PA of children with ASD during summer camp. METHODS: Data were collected on 6 ASD and 6 NT boys (aged 5-6 years) attending an inclusive summer camp. During free play and organized activity, research assistants observed the camp’s social environment and children’s PA using a modified version of the Observational System for Recording Physical Activity of Children – Preschool version. RESULTS: In free play, children with ASD spent significantly less time in Moderate-Vigorous PA (MVPA) while with a peer (1.2%), compared to with a peer group (11.5%) or alone (13.2%). They demonstrated significantly more Light-Moderate-Vigorous PA (LMVPA) while in a solitary social context (68.2%) compared to alone with an adult (25.8%), alone with a peer (34.8%), or with a peer group (28.2%). No significant differences were noted during organized activity. CONCLUSION: Features of the social environment may influence PA levels of children with ASD. Specifically, certain social group contexts may be more PA-promoting than others depending on the setting.

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16. Stackpole EE, Akins MR, Fallon JR. {{N-Myristoylation regulates the axonal distribution of the fragile X-related protein FXR2P}}. {Mol Cell Neurosci};2014 (Aug 7)
Fragile X Syndrome, the leading cause of inherited intellectual disability and autism, is caused by loss of function of Fragile X mental retardation protein (FMRP). FMRP is an RNA binding protein that regulates local protein synthesis in the somatodendritic compartment. However, emerging evidence also indicates important roles for FMRP in axonal and presynaptic function. In particular, FMRP and its homolog FXR2P localize axonally and presynaptically to discrete endogenous structures in the brain termed Fragile X granules (FXGs). FXR2P is a component of all FXGs and is necessary for the axonal and presynaptic localization of FMRP to these structures. We therefore sought to identify and characterize structural features of FXR2P that regulate its axonal localization. Sequence analysis reveals that FXR2P harbors a consensus N-terminal myristoylation sequence (MGXXXS) that is absent in FMRP. Using click chemistry with wild type and an unmyristoylatable G2A mutant we demonstrate that FXR2P is N-myristoylated on glycine 2, establishing it as a lipid-modified RNA binding protein. To investigate the role of FXR2P N-myristoylation in neurons we generated fluorescently tagged wild type and unmyristoylatable FXR2P (WT and G2A, respectively) and expressed them in primary cortical cultures. Both FXR2PWT and FXR2PG2A are expressed at equivalent overall levels and are capable of forming FMRP-containing axonal granules. However, FXR2PWT granules are largely restricted to proximal axonal segments while granules formed with unmyristoylatable FXR2PG2A are localized throughout the axonal arbor, including in growth cones. These studies indicate that N-terminal myristoylation of the RNA binding protein FXR2P regulates its localization within the axonal arbor. Moreover, since FMRP localization within axonal domains requires its association with FXR2P, these findings suggest that FXR2P lipid modification is a control point for the axonal and presynaptic distribution of FMRP.

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17. Sullivan K, Stone WL, Dawson G. {{Potential neural mechanisms underlying the effectiveness of early intervention for children with autism spectrum disorder}}. {Res Dev Disabil};2014 (Aug 7);35(11):2921-2932.

Although evidence supports the efficacy of early intervention for improving outcomes for children with autism spectrum disorder (ASD), the mechanisms underlying their effectiveness remain poorly understood. This paper reviews the research literature on the neural bases of the early core deficits in ASD and proposes three key features of early intervention related to the neural mechanisms that may contribute to its effectiveness in improving deficit areas. These features include (1) the early onset of intensive intervention which capitalizes on the experience-expectant plasticity of the immature brain, (2) the use of treatment strategies that address core deficits in social motivation through an emphasis on positive social engagement and arousal modulation, and (3) promotion of complex neural networks and connectivity through thematic, multi-sensory and multi-domain teaching approaches. Understanding the mechanisms of effective early intervention will enable us to identify common or foundational active ingredients for promoting optimal outcomes in children with ASD.

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18. Taylor JL, Corbett BA. {{A review of rhythm and responsiveness of cortisol in individuals with autism spectrum disorders}}. {Psychoneuroendocrinology};2014 (Jul 22);49C:207-228.

Examination of the hypothalamic-pituitary-adrenal (HPA) axis via cortisol among individuals with autism spectrum disorder (ASD) has been a growing area of research interest. The following review includes investigations of cortisol conducted with cohorts of individuals with ASD across the lifespan over the past four decades. In general, studies find dysregulation when examining the diurnal rhythm as a whole in lower functioning children with ASD; however, limited evidence exists for alterations in higher functioning individuals and in specific aspects of the diurnal cycle (cortisol awakening response, daily decline, variability) relative to typically developing individuals. Studies examining the responsiveness of cortisol in ASD suggest an overall sluggishness of the HPA axis in responding to physiological or physical manipulation. Hypo-responsiveness was observed in stressors that involve social evaluative threat, however, hyper-responsiveness of the HPA axis was observed in situations involving unpleasant stimuli or relatively benign social situations. A number of important considerations when conducting studies of cortisol in ASD cohorts are discussed.

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19. Ten Eycke KD, Muller U. {{Brief Report: New Evidence for a Social-Specific Imagination Deficit in Children with Autism Spectrum Disorder}}. {J Autism Dev Disord};2014 (Aug 8)
Previous research suggests that children with autism have deficits in drawing imaginative content. However, these conclusions are largely based on tasks that require children to draw impossible persons, and performance on this task may be limited by social deficits. To determine the generality of the deficit in imagination in children with autism, we asked 25 children with autism (mean age 9;7) and 29 neurotypically developing children (mean age 8;7) to draw an imaginative person and house. Drawings of imaginary houses by children with autism did not differ from those by neurotypically developing controls, but drawings of persons were significantly less imaginative. These findings suggest that the impairment in imagination among children with autism may be specific to social stimuli.

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20. Weinger PM, Zemon V, Soorya L, Gordon J. {{Low-contrast response Deficits and increased neural noise in children with autism spectrum disorder}}. {Neuropsychologia};2014 (Aug 5)
A battery of short-duration neurophysiological tests were designed and implemented using visual evoked potentials (VEPs) to examine specific neural mechanisms in children with and without autism spectrum disorder (ASD). Contrast-sweep conditions (bright or dark isolated-checks) were used to elicit steady-state VEPs to examine the integrity of ON/OFF pathways, respectively. Children with ASD displayed deficits in low-contrast responses at the stimulus frequency of 12.5Hz, notably under conditions that emphasized activity in the magnocellular pathway. Signal-to-noise ratios were weaker in the ASD group, particularly for the OFF pathway. There were no group differences in the amplitude of responses. In addition, the ASD group displayed significantly higher levels of neural noise than controls. For the response at the stimulus frequency, the ASD group produced a relatively constant level of noise across the contrast range tested, with higher levels than controls at low contrasts and approximately equal levels of noise at moderate to high contrasts.

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21. Yang JC, Chi L, Teichholtz S, Schneider A, Nanakul R, Nowacki R, Seritan A, Reed B, DeCarli C, Iragui VJ, Kutas M, Hagerman PJ, Hagerman RJ, Olichney JM. {{ERP Abnormalities elicited by word repetition in fragile X-associated tremor/ataxia syndrome (FXTAS) and amnestic MCI}}. {Neuropsychologia};2014 (Aug 8)
BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder caused by FMR1 gene premutations, typically associated with frontal-subcortical type cognitive impairments. High prevalence (~50%) of superimposed Alzheimer’s pathology has been reported in FMR1 premutation carriers, and standardized neuropsychological tests have not yielded any robust discriminators between FXTAS and Alzheimer’s disease (AD) dementia. The similarities/differences in memory processes between FXTAS and early AD remain underexplored. METHODS: 32-channel event-related potentials (ERPs) were obtained from a semantic judgment task in which semantically congruous (50%) and incongruous pairs repeat pseudorandomly. The N400 and late positive component (LPC) of 25 FXTAS patients (Mage=71.2, MMSE=26.6) were compared to a matched group of 25 patients with MCI or early AD (1 mild AD dementia, 24 amnestic MCI, of whom 18 later converted to AD; Mage=73.4, MMSE=26.4), and 25 healthy elderly. RESULTS: Both patient groups showed similar reductions in the N400 repetition effect and N400 congruity effect amplitudes, compared to controls, reflecting abnormal semantic priming and repetition priming. The MCI/AD group, however, had significantly smaller LPC word repetition effects and poorer learning and memory on the CVLT than FXTAS. The LPC and N400 repetition effects both correlated with verbal memory across all subjects, but only the N400 correlated with memory in FXTAS. CONCLUSION: FXTAS patients show relative sparing of the LPC repetition effect, and less disruption of explicit memory than prodromal/early AD. N400 abnormalities in FXTAS appear to account for much of their mild impairments in verbal learning and memory.

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22. Yilmaz TU, Gunes A, Posteki G, Okay E. {{Rett syndrome with colon cancer presented with sigmoid volvulus: Report of a case}}. {Int J Surg Case Rep};2014 (Jul 15);5(9):577-579.

INTRODUCTION: Rett syndrome is a progressive neurodevelopment disorder in which MECP gene mutations are responsible and might be related to cancer. PRESENTATION OF CASE: A 22 year-old girl with Rett syndrome was hospitalized for abdominal distention and shock. Abdominal tenderness and distention were revealed in physical examination. Radiological investigations revealed sigmoid volvulus and colonic obstruction. Sigmoid volvulus, sigmoid colon perforation due to sigmoid cancer with liver metastasis were observed at laparotomy. Hartman procedure performed. The patient died on the second postoperative day. DISCUSSION: Rett syndrome has several gastrointestinal pathologies related with inadequate parasympathetic control. Genetic mutations in methyl-CpG-binding protein 2 (MECP2) which has role in several cancer mechanisms is the reason of Rett syndrome. Colon cancer with the underlying gastrointestinal pathologies complicated our case. CONCLUSION: Rett syndrome patients need a high level of concern for gastrointestinal emergencies with cancer risk.

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23. Yoo HJ, Yang SY, Cho IH, Park M, Kim SA. {{Polymorphisms of BDNF gene and autism spectrum disorders: family based association study with korean trios}}. {Psychiatry Investig};2014 (Jul);11(3):319-324.

OBJECTIVE: Autism spectrum disorders (ASDs) are a group of early childhood-onset neurodevelopmental disorders characterized by deficits in social interaction and language skills, and repetitive behaviors. Brain-derived neurotrophic factor (BDNF) plays a critical role in the differentiation of normal neuronal cells during embryonic and postnatal neuronal development through its neurotrophic effects. METHODS: In this study, we performed a family-based association test (FBAT) between single nucleotide polymorphisms (SNPs; rs6265, rs11030101, rs7103411, and rs7103873) or haplotypes in the BDNF gene and affection status or several quantitative traits characterized by ADI-R with151 Korean trios, including a child diagnosed as ASDs. RESULTS: While no significant association was found between SNPs or haplotypes and the ASDs disease status, a quantitative transmission disequilibrium test (QTDT) by using quantitative traits identified associations of the SNPs (rs6265 and rs11030101) with a domain score for « Restricted, Repetitive and Stereotyped patterns of behavior » (C domain), especially at the subdomain scores for « encompassing preoccupation or circumscribed pattern of interest » (C1) (rs6265A allele, dominant model, p-value=0.019; rs11030101 A allele, additive model, p-value=0.015) and « preoccupations with part of objects or non-functional elements of material » (C4) (rs11030101 A allele, additive model, p-value=0.015) within the ADI-R diagnostic algorithm. In addition, significant associations were also identified between the haplotypes and these quantitative traits (C1, p-value=0.016; C4, p-value=0.012). CONCLUSION: We conclude that BDNF gene polymorphisms have a possible role in the pathogenesis of ASDs.

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24. Zalla T. {{Amygdala, oxytocin, and social cognition in autism spectrum disorders}}. {Biol Psychiatry};2014 (Sep 1);76(5):356-357.

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