Pubmed du 21/05/13

Pubmed du jour

2013-05-21 12:03:50

1. Burket JA, Benson AD, Tang AH, Deutsch SI. {{D-Cycloserine Improves Sociability in the BTBR T+ Itpr3tf/J Mouse Model of Autism Spectrum Disorders with Altered Ras/Raf/ERK1/2 Signaling}}. {Brain Res Bull};2013 (May 15)

The genetically-inbred BTBR T+ Itpr3tf/J (BTBR) mouse is a proposed model of autism spectrum disorders (ASDs). Similar to several syndromic forms of ASDs, mTOR activity may be enhanced in this mouse strain as a result of increased Ras signaling. Recently, D-cycloserine, a partial glycineB site agonist that targets the NMDA receptor, was shown to improve the sociability of the Balb/c mouse strain, another proposed genetically-inbred model of ASDs. NMDA receptor activation is an important regulator of mTOR signaling activity. Given the ability of D-cycloserine to improve the sociability of the Balb/c mouse strain and the regulatory role of the NMDA receptor in mTOR signaling, we wondered if D-cycloserine would improve the impaired sociability of the BTBR mouse strain. D-Cycloserine (320mg/kg, ip) improved measures of sociability in a standard sociability paradigm and spontaneous grooming that emerged during social interaction with an ICR stimulus mouse in the BTBR strain; however, similar effects were observed in the Swiss Webster comparator strain, raising questions about their strain-selectivity. Importantly, the profile of D-cycloserine’s effects on both measures of sociability and stereotypies is consistent with that of a desired medication for ASDs; specifically, a desired medication would not improve sociability at the expense of worsening stereotypic behaviors or vice versa.

Lien vers le texte intégral (Open Access ou abonnement)

2. Chung YS, Barch D, Strube M. {{A Meta-Analysis of Mentalizing Impairments in Adults With Schizophrenia and Autism Spectrum Disorder}}. {Schizophr Bull};2013 (May 17)

Mentalizing has been examined both in autism spectrum disorder (ASD) and schizophrenia (SCZ) primarily by either cognitive-linguistic (referred to as verbal) or emotion recognition from eyes (referred to as visual) mentalizing tasks. Each type of task is thought to measure different aspects of mentalizing. Differences in clinical features and developmental courses of each disorder may predict distinct patterns of mentalizing performance across dis orders on each type of task. To test this, a meta-analysis was conducted using 37 studies that assessed mentalizing either verbally or visually in adults with SCZ or ASD. We found that the estimated effect sizes of impairments in verbal and visual mentalizing tasks for both clinical groups were statistically large and at a similar level (overall Hedges’ g = 0.73-1.05). For each disorder, adults with SCZ showed a trend towards larger impairments on verbal (overall Hedges’ g = 0.99) than on visual mentalizing task (overall Hedges’ g = 0.73; Qbet = 3.45, p =.06, df =1). Adults with ASD did not show different levels of impairment on the verbal versus visual tasks (Qbet = 0.08, p =.78, df =1). These results suggest that both clinical groups share, at least in part, some common cognitive processing deficits associated with mentalizing impairments.

Lien vers le texte intégral (Open Access ou abonnement)

3. Goldman S. {{Opinion: Sex, Gender and the Diagnosis of Autism – A Biosocial View of the Male Preponderance}}. {Res Autism Spectr Disord};2013 (Jun);7(6):675-679.

Lien vers le texte intégral (Open Access ou abonnement)

4. Gutierrez JF, Bajaj K, Klugman SD. {{Prenatal screening for fragile x: carriers, controversies, and counseling}}. {Rev Obstet Gynecol};2013;6(1):e1-7.

In addition to causing developmental disability in future offspring, fragile X carrier status has important reproductive and mental health implications for the individual being tested. Accordingly, prenatal carrier screening and diagnosis using DNA-based molecular methods has become crucial in early detection, intervention, and family planning. Although the list of known genetic disorders is growing daily, controversy remains over who should be tested for fragile X. FMR1 gene mutations can result in inherited intellectual disability, infertility, and neurodegeneration syndromes that are encountered by clinicians in a variety of settings. Patients and clinicians are still largely unfamiliar with this disorder, its complicated inheritance, and its heterogeneous phenotype. Debate continues over who should be offered prenatal carrier screening. As more disease screening is offered, pretest counseling will become only more complex and clinicians will further struggle to balance the needs of the individual and allocation of public health resources.

Lien vers Pubmed

5. Iwanaga R, Tanaka G, Nakane H, Honda S, Imamura A, Ozawa H. {{Usefulness of near-infrared spectroscopy to detect brain dysfunction in children with autism spectrum disorder when inferring the mental state of others}}. {Psychiatry Clin Neurosci};2013 (May);67(4):203-209.

AIMS: The purpose of this study was to examine the usefulness of near-infrared spectroscopy (NIRS) for identifying abnormalities in prefrontal brain activity in children with autism spectrum disorders (ASD) as they inferred the mental states of others. METHODS: The subjects were 16 children with ASD aged between 8 and 14 years and 16 age-matched healthy control children. Oxygenated hemoglobin concentration was measured in the subject’s prefrontal brain region on NIRS during tasks expressing a person’s mental state (MS task) and expressing an object’s characteristics (OC task). RESULTS: There was a significant main effect of group (ASD vs control), with the control group having more activity than the ASD group. But there was no significant main effect of task (MS task vs OC task) or hemisphere (right vs left). Significant interactions of task and group were found, with the control group showing more activity than the ASD group during the MS task relative to the OC task. CONCLUSIONS: NIRS showed that there was lower activity in the prefrontal brain area when children with ASD performed MS tasks. Therefore, clinicians might be able to use NIRS and these tasks for conveniently detecting brain dysfunction in children with ASD related to inferring mental states, in the clinical setting.

Lien vers le texte intégral (Open Access ou abonnement)

6. Karanth P, Chandhok TS. {{Impact of Early Intervention on Children with Autism Spectrum Disorders as Measured by Inclusion and Retention in Mainstream Schools}}. {Indian J Pediatr};2013 (May 18)

OBJECTIVES: To follow up the school/educational status of children with a primary diagnosis of Autism Spectrum Disorders (ASD), who had been enrolled in an Early Intervention (EI) program for 1-3 y, before the age of 6. METHODS: Data was collected through a questionnaire covering three specific areas-the families’ success in following the recommendation given on completion of the EI program, issues in schooling and feedback on the EI program. The contact modes included email, post, telephonic interviews and face-to-face interviews. RESULTS: One hundred and two of the 296 children responded to the questionnaire. The responses were analyzed to identify, the number of families who had completed the program and were able to follow through with the recommendation given on completion of the EI program, difficulties faced if any, family feedback on the program and the additional help that they would have liked to receive. The reasons for failure to comply with the recommendations were analyzed. Of the 102 children who responded seven had dropped out midway through the program and 10 had discontinued after one year. Of the remaining 85 who completed the program, 71 were advised mainstreaming (83.5 %) and 14 were advised special school (16.5 %). Sixty-five of the 71 children, who were advised to enroll their child in the mainstream, were in regular school. 76.5 % of the children who completed the EI program were integrated in regular schools, 2 to 7 y after having completed the program. CONCLUSIONS: EI helps in enrolment and retention of substantial numbers of children with ASD in mainstream schools.

Lien vers le texte intégral (Open Access ou abonnement)

7. Ronconi L, Gori S, Giora E, Ruffino M, Molteni M, Facoetti A. {{Deeper attentional masking by lateral objects in children with autism}}. {Brain Cogn};2013 (May 14);82(2):213-218.

Autism spectrum disorder (ASD) is often associated with a detail-oriented perception and overselective attention in visual tasks, such as visual search and crowding. These results were obtained manipulating exclusively the spatial properties of the stimuli: few is known about the spatio-temporal dynamics of visual processing in ASD. In this study we employed an attentional masking (AM) paradigm comparing children with ASD and IQ-matched typically developing (TD) controls. The AM effect refers to an impaired identification of a target followed by a competitive masking object at different proximities in space and time. We found that ASD and TD groups did not differ in the AM effect provoked by the competitive object displayed in the same position of the target. In contrast, children with ASD showed a deeper and prolonged interference than the TD group when the masking object was displayed in the lateral position. These psychophysical results suggest that the inefficient attentional selection in ASD depends on the spatio-temporal interaction between competitive visual objects. These evidence are discussed in the light of the ASD altered neural connectivity hypothesis and the reentrant theory of perception.

Lien vers le texte intégral (Open Access ou abonnement)

8. Whitehouse AJ. {{Complementary and alternative medicine for autism spectrum disorders: Rationale, safety and efficacy}}. {J Paediatr Child Health};2013 (May 20)

Complementary and alternative medicine is widely used for children with autism spectrum disorder, despite uncertainty regarding efficacy. This review describes complementary and alternative practices commonly used among this population, the rationale for the use of each practice, as well as the side-effect profile and evidence for efficacy. The existing evidence base indicates that melatonin can be recommended as a treatment for sleeping disturbances associated with autism spectrum disorder, while secretin can be rejected as an efficacious treatment for broader autistic symptoms. There is insufficient evidence to draw conclusions on the efficacy of modified diets, hyperbaric oxygen therapy, immune therapy, and vitamin and fatty acid supplementation. There is a clear need for methodologically rigorous studies to provide evidence-based guidance to families and clinicians regarding complementary and alternative practices for individuals with autism spectrum disorders.

Lien vers le texte intégral (Open Access ou abonnement)

9. Yang JC, Simon C, Niu YQ, Bogost M, Schneider A, Tassone F, Seritan A, Grigsby J, Hagerman PJ, Hagerman RJ, Olichney JM. {{Phenotypes of hypofrontality in older female fragile x premutation carriers}}. {Ann Neurol};2013 (May 20)

Objective To investigate the nature of cognitive impairments and underlying brain mechanisms in older female fragile X premutation carriers with and without fragile X-associated tremor/ataxia syndrome (FXTAS). Methods Extensive neuropsychological testing and cognitive event-related brain potentials (ERPs, particularly, the auditory P300) were examined in 84 female participants: 33 fragile X premutation carriers with FXTAS (mean age = 62.8), 25 premutation carriers without FXTAS (mean age = 55.4) and 26 normal healthy controls (mean age = 59.3). Results Both premutation groups exhibited executive dysfunction on the Behavioral Dyscontrol Scale (BDS), with subtle impairments in inhibition and performance monitoring in female carriers without FXTAS, and more substantial deficits in FXTAS women. However, the female carrier group without FXTAS showed more pronounced deficiencies in working memory. Abnormal ERPs were recorded over the frontal lobes, where FXTAS patients showed both P300 amplitude reduction and latency prolongation, while only decreased frontal P300 amplitudes were found in carriers without FXTAS. These frontal P3 measures correlated with executive function and information processing speed. Interpretation The neuropsychological testing and ERP results of the present study provide support for the hypothesis that executive dysfunction is the primary cognitive impairment among older female premutation carriers both with and without FXTAS, although these deficits are relatively mild compared to those in FXTAS males. These findings are consistent with a synergistic effect of the premutation and aging on cognitive impairment among older female fragile X premutation carriers, even in those without FXTAS symptoms. ANN NEUROL 2013. (c) 2013 American Neurological Association.

Lien vers le texte intégral (Open Access ou abonnement)