Pubmed du 10/09/11

Pubmed du jour

2011-09-10 12:03:50

1. Aiello TP, Whitaker-Azmitia PM. {{Sexual Differentiation and the Neuroendocrine Hypothesis of Autism}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

The phenotypic expression of autism spectrum disorders varies widely in severity and characteristics and it is, therefore, likely that a number of etiological factors are involved. However, one finding which has been found consistently is that there is a greater incidence of autism in boys than girls. Recently, attention has been given to the extreme male hypothesis-that is that autism behaviors are an extreme form of typical male behaviors, including lack of empathy and language deficits but an increase in so-called systemizing behaviors, such as attention to detail and collecting. This points to the possibility that an alteration during sexual differentiation of the brain may occur in autism. During sexual differentiation of the brain, two brain regions are highly sexually dimorphic-the amygdala and the hypothalamus. Both of these regions are also implicated in the neuroendocrine hypothesis of autism, wherein a balance between oxytocin and cortisol may contribute to the disorder. We are thus proposing that the extreme male hypothesis and the neuroendocrine hypothesis are in fact compatible in that sexual differentiation of the brain towards an extreme male phenotype would result in the neuroendocrine changes proposed in autism. We have preliminary data, treating developing rat pups with the differentiating hormone 17-beta estradiol during a critical time and showing changes in social behaviors and oxytocin, to support this hypothesis. Further studies should be undertaken to confirm the role of extremes of normal sexual differentiation in producing the neuroendocrine changes associated with autism. Anat Rec, 2011. (c) 2011 Wiley-Liss, Inc.

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2. Alderson-Day B. {{Verbal problem-solving in autism spectrum disorders: A problem of plan construction?}}. {Autism Res}. 2011 Sep 8.

Children with autism spectrum disorders (ASD) adopt less efficient strategies than typically developing controls (TD) on verbal problem-solving tests such as the Twenty Questions Task. This study examined the hypotheses that this can be explained by differences in (i) planning processes or (ii) selective attention. Twenty-two children with ASD and 21 TD controls matched for age (M(age) = 13:7) and cognitive ability (M(FSIQ) = 96.42) were tested on an adapted version of Twenty Questions and two planning tasks. ASD participants could recognize effective questions as well as TD participants on a forced-choice question discrimination task, but were observed to construct plans that were significantly less efficient. ASD performance was also specifically reduced when items could not be physically removed from the testing array, although this effect could be ameliorated by keeping a written record of participant questions during search. These findings indicate that ASD participants are sensitive to the within-task executive demands of Twenty Questions, but that their inefficiency in strategy relates to planning processes and question selection pretask. The implications for understanding ASD problem-solving skills and their impact on everyday functioning are discussed. Autism Res 2011,4:xxx-xxx. (c) 2011 International Society for Autism Research, Wiley Periodicals, Inc.

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3. Azmitia EC, Singh JS, Hou XP, Wegiel J. {{Dystrophic Serotonin Axons in Postmortem Brains from Young Autism Patients}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

Autism causes neuropathological changes in varied anatomical loci. A coherent neural mechanism to explain the spectrum of autistic symptomatology has not been proposed because most anatomical researchers focus on point-to-point functional neural systems (e.g., auditory and social networks) rather than considering global chemical neural systems. Serotonergic neurons have a global innervation pattern. Disorders Research Program, AS073234, Program Project (JW). Their cell bodies are found in the midbrain but they project their axons throughout the neural axis beginning in the fetal brain. This global system is implicated in autism by animal models and by biochemical, imaging, pharmacological, and genetics studies. However, no anatomical studies of the 5-HT innervation of autistic donors have been reported. Our review presents immunocytochemical evidence of an increase in 5-HT axons in postmortem brain tissue from autism donors aged 2.8-29 years relative to controls. This increase is observed in the principle ascending fiber bundles of the medial and lateral forebrain bundles, and in the innervation density of the amygdala and the piriform, superior temporal, and parahippocampal cortices. In autistic donors 8 years of age and up, several types of dystrophic 5-HT axons were seen in the termination fields. One class of these dystrophic axons, the thick heavily stained axons, was not seen in the brains of patients with neurodegenerative diseases. These findings provide morphological evidence for the involvement of serotonin neurons in the early etiology of autism, and suggest new therapies may be effective to blunt serotonin’s trophic actions during early brain development in children. Anat Rec, 2011. (c) 2011 Wiley-Liss, Inc.

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4. Bernier R, Gerdts J, Munson J, Dawson G, Estes A. {{Evidence for broader autism phenotype characteristics in parents from multiple-incidence autism families}}. {Autism Res}. 2011 Sep 8.

The broader autism phenotype (BAP) was assessed in parents who have two or more children with autism spectrum disorder (ASD) (multiplex (MPX) autism), parents who have no more than one child with ASD (simplex autism), parents who have a child with developmental delay without ASD, and parents who have typically developing children. Clinicians, naive to parent group membership status, rated BAP characteristics from videotaped administration of the Broader Autism Phenotype Symptom Scale (BPASS). Differences among groups in BPASS scores in the four assessed domains (social motivation, conversational skills, expressiveness, and restricted interests) were examined using multivariate ANOVA and post hoc comparisons. Further, ratings of videotapes by observers naive to family status were compared with live, non-naive ratings by observers who were aware of family status (non-naive). Findings demonstrate that the BPASS is an instrument resistant to rater bias. Parents from MPX autism families showed significantly more autism phenotype characteristics than the parents in the other groups. Moreover, the parents from simplex autism families did not differ from the parents of children with developmental delay or typical development. Finally, no differences between live, non-naive ratings and videotaped, naive ratings were observed. These findings suggest that characteristics of the BAP, specifically in the social and communication domains, are present in MPX autism parents to a greater degree than simplex autism and control parents. Further, the results provide support for the notion that genetic transmission mechanisms may differ between families with more than one child with autism and families with only one child with autism. Autism Res 2011,4:xxx-xxx. (c) 2011 International Society for Autism Research, Wiley Periodicals, Inc.

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5. Blatt GJ, Fatemi SH. {{Alterations in GABAergic Biomarkers in the Autism Brain: Research Findings and Clinical Implications}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

Autism is a pervasive developmental disorder characterized by repetitive stereotyped behavior, social-emotional deficits, and delayed or absent language abilities. There are known neuropathologies in the autism brain affecting limbic, cerebellar, and cortical structures but the neurochemical profile of affected individuals, revealed in postmortem tissue studies, is only recently emerging. One major component that appears highly impacted in autism is the GABAergic system. It is now apparent that there are widespread significant effects in many distributed regions in the autism brain revealed by histochemical, autoradiographic, and biochemical studies. The key synthesizing enzymes for GABA, glutamic acid decarboxylase type 65 and 67 (GAD65 and GAD67), are decreased in the cerebellum and closer examination of mRNA levels revealed that it is largely due to decreases in Purkinje cells and a subpopulation of larger dentate neurons as measured by in situ hybridization studies. Other cell types had either normal GAD levels (Golgi cells, smaller dentate interneurons, and stellate cells) or increased levels (basket cells). GABA receptor density, number, and protein expression are all decreased in the cerebellum and in select cortical areas. GABA(A) and GABA(B) subunit protein expression was significantly reduced in cerebellum, BA 9 and BA 40. Benzodiazepine binding sites were significantly reduced in the hippocampus and anterior cingulate cortex (BA 24). Taken together, data from these studies suggest that there is a marked dysregulation of the inhibitory GABA system in the autism brain affecting particular biomarkers localized to specific cell types and lamina likely influencing circuitry and behavior. Anat Rec, 2011. (c) 2011 Wiley-Liss, Inc.

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6. Cheuk DK, Wong V, Chen WX. {{Acupuncture for autism spectrum disorders (ASD)}}. {Cochrane Database Syst Rev}. 2011;9:CD007849.

BACKGROUND: Autism spectrum disorders (ASD) are characterized by impairment in social interaction, impairment in communication and lack of flexibility of thought and behavior. Acupuncture, which involves the use of needles or pressure to specific points on the body, is used widely in Traditional Chinese Medicine and increasingly within a western medical paradigm. It has sometimes been used as a treatment aimed at improving ASD symptoms and outcomes, but its clinical effectiveness and safety has not been rigorously reviewed. OBJECTIVES: To determine the effectiveness of acupuncture for people with ASD in improving core autistic features, as well as communication, cognition, overall functioning and quality of life, and to establish if it has any adverse effects. SEARCH STRATEGY: We searched the following databases on 30 September 2010: CENTRAL (The Cochrane Library, 2010, Issue 3), MEDLINE (1950 to September 2010 Week 2), EMBASE (1980 to 2010 Week 38), PsycINFO, CINAHL, China Journal Full-text Database, China Master Theses Full-text Database, China Doctor Dissertation Full-text Database, China Proceedings of Conference Database, Index to Taiwan Periodical Literature System, metaRegister of Controlled Trials and the Chinese Clinical Trials Registry. We also searched AMED (26 February 2009) and Dissertation Abstracts International (3 March 2009), but these were no longer available to the authors or editorial base at the date of the most recent search. TCMLARS (Traditional Chinese Medical Literature Analysis and Retrieval System) was last searched on 3 March 2009. SELECTION CRITERIA: We included randomized and quasi-randomized controlled trials. We included studies comparing an acupuncture group with at least one control group that used no treatment, placebo or sham acupuncture treatment in people with ASD. We excluded trials that compared different forms of acupuncture or compared acupuncture with another treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted trial data and assessed the risk of bias in the trials. We used relative risk (RR) for dichotomous data and mean difference (MD) for continuous data. MAIN RESULTS: We included 10 trials that involved 390 children with ASD. The age range was three to 18 years and the treatment duration ranged from four weeks to nine months. The studies were carried out in Hong Kong, mainland China and Egypt.Two trials compared needle acupuncture with sham acupuncture and found no difference in the primary outcome of core autistic features (RFRLRS total score: MD 0.09; 95% CI -0.03 to 0.21, P = 0.16), although results suggested needle acupuncture might be associated with improvement in some aspects of the secondary outcomes of communication and linguistic ability, cognitive function and global functioning.Six trials compared needle acupuncture plus conventional treatment with conventional treatment alone. The trials used different primary outcome measures and most could not demonstrate effectiveness of acupuncture in improving core autistic features in general, though one trial reported patients in the acupuncture group were more likely to have improvement on the Autism Behavior Checklist (RR 1.53; 95% CI 1.09 to 2.16, P = 0.02) and had slightly better post-treatment total scores (MD -5.53; 95% CI -10.76 to -0.31, P = 0.04). There was no evidence that acupuncture was effective for the secondary outcome of communication and linguistic ability, though there seemed to be some benefit for the secondary outcomes of cognitive function and global functioning.Two trials compared acupressure plus conventional treatment with conventional treatment alone and did not report on the primary outcome. Individual study results suggested there may be some benefit from acupressure for certain aspects of the secondary outcomes of communication and linguistic ability, cognitive function and global functioning.Four trials reported some adverse effects, though there was little quantitative information, and at times both intervention and control groups experienced them. Adverse effects noted included bleeding, crying due to fear or pain, irritability, sleep disturbance and increased hyperactivity. None of the trials reported on quality of life.There are a number of problems with the evidence base: the trials were few in number and included only children; six of the trials were at high risk of bias; they were heterogeneous in terms of participants and intervention; they were of short duration and follow-up; they reported inconsistent and imprecise results, and, due to carrying out large numbers of analyses, they were at risk of false positivity. AUTHORS’ CONCLUSIONS: Current evidence does not support the use of acupuncture for treatment of ASD. There is no conclusive evidence that acupuncture is effective for treatment of ASD in children and no RCTs have been carried out with adults. Further high quality trials of larger size and longer follow-up are needed.

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7. Davidovic L, Navratil V, Bonaccorso CM, Catania MV, Bardoni B, Dumas ME. {{A metabolomic and systems biology perspective on the brain of the Fragile X syndrome mouse model}}. {Genome Res}. 2011 Sep 7.

Fragile X syndrome (FXS) is the first cause of inherited intellectual disability, due to the silencing of the X-linked Fragile X Mental Retardation 1 gene encoding the RNA-binding protein FMRP. While extensive studies have focused on the cellular and molecular basis of FXS, neither human fragile X patients nor the mouse model of FXS -the Fmr1-null mouse- have been profiled systematically at the metabolic and neurochemical level to provide a complementary perspective on the current, yet scattered, knowledge of FXS. Using proton high-resolution magic angle spinning nuclear magnetic resonance (1H HR-MAS NMR)-based metabolic profiling, we have identified a metabolic signature and biomarkers associated with FXS in various brain regions of Fmr1-deficient mice. Our study highlights for the first time that Fmr1 gene inactivation has profound, albeit coordinated consequences in brain metabolism leading to alterations in: i) neurotransmitter levels, ii) osmoregulation, iii) energy metabolism and iv) oxidative stress response. To functionally connect Fmr1-deficiency to its metabolic biomarkers, we derived a functional interaction network based on the existing knowledge (literature and databases) and show that the FXS metabolic response is initiated by distinct mRNA targets and proteins interacting with FMRP, and then relayed by numerous regulatory proteins. This novel « integrated metabolome and interactome mapping » (iMIM) approach advantageously unifies novel metabolic findings with previously unrelated knowledge and highlights the contribution of novel cellular pathways to the pathophysiology of FXS. These metabolomic and integrative systems biology strategies will contribute to develop potential drug targets and novel therapeutic interventions, which will eventually benefit FXS patients.

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8. Dow CT. {{Mycobacterium paratuberculosis and autism: Is this a trigger?}}. {Med Hypotheses}. 2011 Sep 6.

Autism is a heterogeneous group of life-long neurologic problems that begin in childhood. Success in efforts to understand and treat autism has been mostly elusive. The role of autoimmunity in autism has gained recognition both for associated systemic autoimmune disease and the presence of brain autoantibodies in autistic children and their family members. There is an acknowledged genetic susceptibility to autism – most notably allotypes of complement C4. C4 defects are associated with several autoimmune diseases and also confer susceptibility to mycobacterial infections. Mycobacterium avium ss. paratuberculosis (MAP) causes an enteric inflammatory disease in ruminant animals (Johne’s disease) and is the putative cause of the very similar Crohn’s disease in humans. Humans are widely exposed to MAP in food and water. MAP has been also linked to ulcerative colitis, irritable bowel syndrome, sarcoidosis, Blau syndrome, autoimmune (Type 1) diabetes, Hashimoto’s thyroiditis and multiple sclerosis. Environmental agents are thought to trigger autism in the genetically at risk. Molecular mimicry is the proposed mechanism by which MAP is thought to trigger autoantibodies. Autoantibodies to brain myelin basic protein (MBP) is a common feature of autism. This article considers the subset of autoimmunity-related autism patients and postulates that MAP, through molecular mimicry to its heat shock protein HSP65, triggers autism by stimulating antibodies that cross react with myelin basic protein (MBP).

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9. Fairless AH, Shah RY, Guthrie AJ, Li H, Brodkin ES. {{Deconstructing Sociability, An Autism-Relevant Phenotype, in Mouse Models}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

Reduced sociability is a core feature of autism spectrum disorders (ASD) and is highly disabling, poorly understood, and treatment refractory. To elucidate the biological basis of reduced sociability, multiple laboratories are developing ASD-relevant mouse models in which sociability is commonly assessed using the Social Choice Test. However, various measurements included in that test sometimes support different conclusions. Specifically, measurements of time the « test » mouse spends near a confined « stimulus » mouse (chamber scores) sometimes support different conclusions from measurements of time the test mouse sniffs the cylinder containing the stimulus mouse (cylinder scores). This raises the question of which type of measurements are best for assessing sociability. We assessed the test-retest reliability and ecological validity of chamber and cylinder scores. Compared with chamber scores, cylinder scores showed higher correlations between test and retest measurements, and cylinder scores showed higher correlations with time spent in social interaction in a more naturalistic phase of the test. This suggests that cylinder scores are more reliable and valid measures of sociability in mouse models. Cylinder scores are reported less commonly than chamber scores, perhaps because little work has been done to establish automated software systems for measuring the former. In this study, we found that a particular automated software system performed at least as well as human raters at measuring cylinder scores. Our data indicate that cylinder scores are more reliable and valid than chamber scores, and that the former can be measured very accurately using an automated video analysis system in ASD-relevant models. Anat Rec, 2011. (c) 2011 Wiley-Liss, Inc.

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10. Fatemi SH, Folsom TD, Kneeland RE, Liesch SB. {{Metabotropic Glutamate Receptor 5 Upregulation in Children with Autism is Associated with Underexpression of Both Fragile X Mental Retardation Protein and GABA(A) Receptor Beta 3 in Adults with Autism}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

Recent work has demonstrated the impact of dysfunction of the GABAergic signaling system in brain and the resultant behavioral pathologies in subjects with autism. In animal models, altered expression of Fragile X mental retardation protein (FMRP) has been linked to downregulation of GABA receptors. Interestingly, the autistic phenotype is also observed in individuals with Fragile X syndrome. This study was undertaken to test previous theories relating abnormalities in levels of FMRP to GABA(A) receptor underexpression. We observed a significant reduction in levels of FMRP in the vermis of adults with autism. Additionally, we found that levels of metabotropic glutamate receptor 5 (mGluR5) protein were significantly increased in vermis of children with autism versus age and postmortem interval matched controls. There was also a significant decrease in level of GABA(A) receptor beta 3 (GABRbeta3) protein in vermis of adult subjects with autism. Finally, we found significant increases in glial fibrillary acidic protein in vermis of both children and adults with autism when compared with controls. Taken together, our results provide further evidence that altered FMRP expression and increased mGluR5 protein production potentially lead to altered expression of GABA(A) receptors. Anat Rec,, 2011. (c) 2011 Wiley-Liss, Inc.

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11. Lin RC. {{Special Issue: New Concepts in Developing Brain Disorders-Autism}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

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12. Pinborough-Zimmerman J, Bilder D, Bakian A, Satterfield R, Carbone PS, Nangle BE, et al. {{Sociodemographic risk factors associated with autism spectrum disorders and intellectual disability}}. {Autism Res}. 2011 Sep 8.

This study examined the hypotheses that (1) sociodemographic risk factors in young children with autism spectrum disorders (ASD) and/or intellectual disability (ID) significantly vary by disability type, and (2) measures of income (mean adjusted gross income, mean federal taxes paid, and mean tax exemptions) significantly increase between 1994 and 2002, and are lower in families with a child with ASD and/or ID compared with the general population. A multiple source surveillance system utilizing a retrospective record review was used to identify ASD and ID cases from a population of 26,108 eight-year-old children born in 1994 and living in Utah in 2002. ASD without ID (ASD-only, n = 99) cases were significantly more likely to be male (P<0.01) and have mothers of White non-Hispanic ethnicity (P = 0.02). ASD with ID (ASD/ID, n = 33) cases were significantly more likely to be male (P<0.01) and have mothers older than 34 years (P = 0.03). ID without ASD (ID-only, n = 113) cases were significantly more likely to have fathers older than 34 years (P<0.01) and were significantly less likely to have mothers with >13 years education (P<0.01). Measures of income for cases at birth and at 8 years of age were not significantly lower than the general population and mean adjusted income of cases significantly increased from birth to 8 years of age. Investigations focused on defining early sociodemographic risk factors by different endophenotypes of ASD may assist in identifying risk factors for this complex group of neurodevelopmental disorders. Aggregate tax information may be a unique resource to utilize for population-based analysis. Autism Res 2011,4:xxx-xxx. (c) 2011 International Society for Autism Research, Wiley Periodicals, Inc.

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13. Reddy A, Graves C, Augustyn M. {{Parents Seek Early Intervention Services for a Two-Year-Old Without Autism}}. {J Dev Behav Pediatr}. 2011 Sep 7.

CASE:: Sam is a 27-month-old boy who you have followed since birth. He lives with his parents in a small resort town approximately 90 miles outside a major city. Both his parents are professionals in their late 30s and have been highly involved in his care since birth. At the 12-month visit, they were concerned about his difficulty regulating. He was not sleeping through the night and had significant difficulty with baths. His physical examination and growth were normal. His eye contact was good, although it was difficult to see him smile. He had 1 or 2 words and was beginning to walk independently.At the 15-month checkup, they continued to be concerned about his poor regulation. He napped sporadically, and he was very difficult to take out on errands as he did not like his car seat. He now had approximately 10 single words, was using his fingers to point and very clearly waved « bye bye » as soon as you entered the room.At the 18-month checkup, they state that he has not yet learned the word « no. » He will follow a 1-step command when he wants to but now has 15 single words without any combinations. He points for his needs and to show them something. He has become increasingly « shy » around strangers and prefers to play with one other child as opposed to a larger group. He does not like loud noises and prefers to go barefoot constantly. His physical examination was again normal as was his growth. He is referred for a full hearing evaluation, which is also normal. The family was referred to early intervention, and he began receiving speech and language therapy and occupational therapy for his sensory challenges as well as a play group.At the 24-month checkup, his language continued to consist of single words-now approximately 30. When the parents do not understand what he wants, he will often tantrum and has started banging his head on the floor when frustrated. He has no repetitive behaviors and is starting to demonstrate imaginative play. Bath time has becoming increasingly challenging because he does not like the sensation of soap and the water temperature must be « just right. » You refer the child to a Developmental and Behavioral Pediatrician for evaluation and at 28 months he is seen. During his testing visit, he had decreased eye contact and followed his own agenda but improved significantly as testing progressed. As he got more comfortable, he began making good eye contact, social referenced, and exhibited joint attention with his parents and the examiner. He did not meet criteria for an autism spectrum disorder or specifically pervasive developmental disorder-not otherwise specified (PDD-NOS). He was given a diagnosis of mixed receptive and expressive language delay and disruptive behavior disorder with sensory processing problems.The parents come to you a month after their evaluation visit asking you to give him a « listed diagnosis of PDD-NOS » that could be removed when he turns 3 years so that he may qualify for increased hours of services-up to 15 hours per week-as well as applied behavioral analysis therapy. A behavioral therapist through early intervention has told the family that he would benefit from this increased intervention, specifically applied behavioral analysis but the only way he can receive it is with a « medical diagnosis » on the autism spectrum. What do you do next?

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14. Rodriguez-Porcel F, Green D, Khatri N, Harris SS, May WL, Lin RC, et al. {{Neonatal Exposure of Rats to Antidepressants Affects Behavioral Reactions to Novelty and Social Interactions in a Manner Analogous to Autistic Spectrum Disorders}}. {Anat Rec (Hoboken)}. 2011 Sep 8.

We have demonstrated that neonatal exposure to selective serotonin reuptake inhibitors has lasting effects on behavior and serotonergic neurons in Long Evans rats. Hyperserotoninemia and altered sensory processing are reported in autistic spectrum disorders (ASD). We hypothesized that early life exposure to SSRIs alters sensory processing, disrupts responses to novelty, and impairs social interactions in a manner similar to that observed in ASD. Male and female Long-Evans rat pups were administered citalopram, buproprion, fluoxetine, or saline from postnatal day (P) 8-21. Rats were tested for response to a novel tone before weaning (P25). Later, rats were tested 2x for response to a novel object (P39), and to a novel conspecific (P78, P101). In addition, rats were assessed for juvenile play behaviors (P32-P34) and later, we assessed sexual response to an estrus female in male rats (P153-184). Antidepressant exposure increased freezing after tone, diminished novel object exploration, and reduced conspecific interaction up to 3x compared to saline exposed rats. Juvenile play was profoundly reduced in antidepressant-exposed males when compared to saline exposed groups. Exposure to the SSRIs, but not bupropion disrupted male sexual behaviors. Moreover, specific male responses to female proceptive behaviors were disrupted in SSRI, but not bupropion exposed rats. We conclude that neonatal exposure to antidepressants in rats results in sensory and social abnormalities that parallel many of those reported in ASD. Anat Rec,, 2011. (c) 2011 Wiley-Liss, Inc.

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15. Rosenberg L, Ratzon NZ, Jarus T, Bart O. {{Perceived environmental restrictions for the participation of children with mild developmental disabilities}}. {Child Care Health Dev}. 2011 Sep 9.

Aim In light of the International Classification of Functioning, and Health (ICF) model, to assess whether parents of children with mild developmental disabilities perceived various environmental factors as barriers to their child’s participation, and whether these factors have a unique contribution to the total explained variance of participation, beyond personal factors. Methods Seventy-nine kindergarten children (mean age 5.20 +/- 0.52 years old) with mild developmental disabilities and their parents participated in the study. Three questionnaires measuring the child’s participation, performance skills and environmental factors were completed by the parents. Results Parents perceived environmental factors as slightly restricting to their child’s participation. Associations were found between home and education factors and the dimensions of child participation – independence, enjoyment and parental satisfaction. Although parents perceived human environmental factors as more restricting than physical factors at home, regression analysis revealed that the latter was found to affect the child participation dimension of independence beyond the contribution of personal factors. Interpretation These findings are the first, to our knowledge, to support the contribution of environmental factors to the participation of young children with mild developmental disabilities. The results show that environmental factors have significant slight contribution to child’s independence in participation beyond other predictors (i.e. personal factors). Therefore, it is recommended to include environmental restrictions measurement in the child evaluation process to facilitate effective intervention programs.

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16. South M, Larson MJ, White SE, Dana J, Crowley MJ. {{Better fear conditioning is associated with reduced symptom severity in autism spectrum disorders}}. {Autism Res}. 2011 Sep 8.

Evidence from behavioral and neuroimaging studies suggest that atypical amygdala function plays a critical role in the development of autism spectrum disorders (ASD). The handful of psychophysiological studies examining amygdala function in ASD using classical fear conditioning paradigms have yielded discordant results. We recorded skin conductance response (SCR) during a simple discrimination conditioning task in 30 children and adolescents (ages 8-18) diagnosed with high-functioning ASD and 30 age- and IQ-matched, typically developing controls. SCR response in the ASD group was uniquely and positively associated with social anxiety; and negatively correlated with autism symptom severity, in particular with social functioning. Fear conditioning studies have tremendous potential to aid understanding regarding the amygdale’s role in the varied symptom profile of ASD. Our data demonstrate that such studies require careful attention to task-specific factors, including task complexity; and also to contributions of dimensional, within-group factors that contribute to ASD heterogeneity. Autism Res 2011,4:xxx-xxx. (c) 2011 International Society for Autism Research, Wiley Periodicals, Inc.

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17. Thanseem I, Nakamura K, Anitha A, Suda S, Yamada K, Iwayama Y, et al. {{Association of Transcription Factor Gene LMX1B with Autism}}. {PLoS One}. 2011;6(8):e23738.

Multiple lines of evidence suggest a serotoninergic dysfunction in autism. The role of LMX1B in the development and maintenance of serotoninergic neurons is well known. In order to examine the role, if any, of LMX1B with autism pathophysiology, a trio-based SNP association study using 252 family samples from the AGRE was performed. Using pair-wise tagging method, 24 SNPs were selected from the HapMap data, based on their location and minor allele frequency. Two SNPs (rs10732392 and rs12336217) showed moderate association with autism with p values 0.018 and 0.022 respectively in transmission disequilibrium test. The haplotype AGCGTG also showed significant association (p = 0.008). Further, LMX1B mRNA expressions were studied in the postmortem brain tissues of autism subjects and healthy controls samples. LMX1B transcripts was found to be significantly lower in the anterior cingulate gyrus region of autism patients compared with controls (p = 0.049). Our study suggests a possible role of LMX1B in the pathophysiology of autism. Based on previous reports, it is likely to be mediated through a seretoninergic mechanism. This is the first report on the association of LMX1B with autism, though it should be viewed with some caution considering the modest associations we report.

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