1. Berman RF, Buijsen RA, Usdin K, Pintado E, Kooy F, Pretto D, Pessah IN, Nelson DL, Zalewski Z, Charlet-Bergeurand N, Willemsen R, Hukema RK. {{Mouse models of the fragile X premutation and fragile X-associated tremor/ataxia syndrome}}. {J Neurodev Disord}. 2014; 6(1): 25.
Carriers of the fragile X premutation (FPM) have CGG trinucleotide repeat expansions of between 55 and 200 in the 5′-UTR of FMR1, compared to a CGG repeat length of between 5 and 54 for the general population. Carriers were once thought to be without symptoms, but it is now recognized that they can develop a variety of early neurological symptoms as well as being at risk for developing the late onset neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Several mouse models have contributed to our understanding of FPM and FXTAS, and findings from studies using these models are summarized here. This review also discusses how this information is improving our understanding of the molecular and cellular abnormalities that contribute to neurobehavioral features seen in some FPM carriers and in patients with FXTAS. Mouse models show much of the pathology seen in FPM carriers and in individuals with FXTAS, including the presence of elevated levels of Fmr1 mRNA, decreased levels of fragile X mental retardation protein, and ubiquitin-positive intranuclear inclusions. Abnormalities in dendritic spine morphology in several brain regions are associated with neurocognitive deficits in spatial and temporal memory processes, impaired motor performance, and altered anxiety. In vitro studies have identified altered dendritic and synaptic architecture associated with abnormal Ca(2+) dynamics and electrical network activity. FPM mice have been particularly useful in understanding the roles of Fmr1 mRNA, fragile X mental retardation protein, and translation of a potentially toxic polyglycine peptide in pathology. Finally, the potential for using these and emerging mouse models for preclinical development of therapies to improve neurological function in FXTAS is considered.
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2. Binkley CJ, Johnson KW, Abadi M, Thompson K, Shamblen SR, Young L, Zaksek B. {{Improving the oral health of residents with intellectual and developmental disabilities: An oral health strategy and pilot study}}. {Eval Program Plann}. 2014; 47C: 54-63.
This article presents an oral health (OH) strategy and pilot study focusing on individuals with intellectual and/or developmental disabilities (IDD) living in group homes. The strategy consists of four components: (1) planned action in the form of the behavioral contract and caregiver OH action planning; (2) capacity building through didactic and observation learning training; (3) environmental adaptations consisting of additional oral heath devices and strategies to create a calm atmosphere; and (4) reinforcement by post-training coaching. A pilot study was conducted consisting of pre- and post-assessment data collected 1 week before and 1 week after implementing a 1-month OH strategy. The study sample comprised 11 group homes with 21 caregivers and 25 residents with IDD from one service organization in a Midwestern city. A process evaluation found high-quality implementation of the OH strategy as measured by dosage, fidelity, and caregiver reactions to implementing the strategy. Using repeated cross-sectional and repeated measures analyses, we found statistically significant positive changes in OH status and oral hygiene practices of residents. Caregiver self-efficacy as a mechanism of change was not adequately evaluated; however, positive change was found in some but not all types of caregiver OH support that were assessed. Lessons learned from implementing the pilot study intervention and evaluation are discussed, as are the next steps in conducting an efficacy study of the OH strategy.
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3. Hellendoorn A. {{Understanding social engagement in autism: being different in perceiving and sharing affordances}}. {Front Psychol}. 2014; 5: 850.
In the current paper I will argue that the notion of affordances offers an alternative to theory of mind (ToM) approaches in studying social engagement in general and in explaining social engagement in autism spectrum disorder (ASD) specifically. Affordances are the possibilities for action offered by the environment. In contrast to ToM approaches, the concept of affordances implies the complementarity of person and environment and rejects the dualism of mind and behavior. In line with the Gibsonian idea that a child must eventually perceive the affordances of the environment for others as well for herself in order to become socialized, I will hypothesize that individuals with ASD often do not perceive the same affordances in the environment as other people do and have difficulties perceiving others’ affordances. This can lead to a disruption of interpersonal behaviors. I will further argue that the methods for studying social engagement should be adapted if we want to take interaction into account.
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4. Kotsis K, Soulis S, Carvalho AF, Hyphantis T. {{Psychological distress among parents having offspring with autism spectrum disorder: Authors’ reply}}. {Disabil Health J}. 2014.
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5. Millard PH, McLaren JL, Coffey DB. {{Lurasidone treatment in a child with autism spectrum disorder with irritability and aggression}}. {J Child Adolesc Psychopharmacol}. 2014; 24(6): 354-6.
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6. Nicolaidis C, Kripke CC, Raymaker D. {{Primary Care for Adults on the Autism Spectrum}}. {Med Clin North Am}. 2014; 98(5): 1169-91.
Autism spectrum disorder (ASD) is defined by differences in social communication and restricted, repetitive patterns of behavior, interests, or activities. Skills and challenges can change depending on environmental stimuli, supports, and stressors. Quality of life can be improved by the use of accommodations, assistive technologies, therapies to improve adaptive function or communication, caregiver training, acceptance, access, and inclusion. This article focuses on the identification of ASD in adults, referrals for services, the recognition of associated conditions, strategies and accommodations to facilitate effective primary care services, and ethical issues related to caring for autistic adults.
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7. Peprah E. {{Understanding decreased fertility in women carriers of the FMR1 premutation: a possible mechanism for Fragile X-Associated Primary Ovarian Insufficiency (FXPOI)}}. {Reprod Health}. 2014; 11(1): 67.
Fragile X syndrome (FXS) and its associated disorders are caused by the expansion of the CGG repeat in the 5′ untranslated region of the fragile X mental retardation 1 gene (FMR1). The full mutation, defined as >200 cytosine-guanine-guanine (CGG) triplet repeats, causes FXS. Individuals with 55-199 CGG repeats, classified as premutation carriers, are affected by two distinct disorders depending on their premutation status. Disorders associated with premutation carriers include: Fragile X-associated Tremor Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI). The molecular similarities of FXTAS and FXPOI (e.g. overabundance of FMR1 transcript and intranuclear inclusions) suggest that similar molecular mechanisms underlie both FXTAS and FXPOI. The current hypothesis describes the underlying mechanism for FXTAS as an mRNA gain-of-function mutation, however the underlying mechanism for FXPOI remains unresolved. New data suggests that repeat associated non-AUG (RAN) translation could underlie FXPOI.
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8. Porges SW, Bazhenova OV, Bal E, Carlson N, Sorokin Y, Heilman KJ, Cook EH, Lewis GF. {{Reducing auditory hypersensitivities in autistic spectrum disorder: preliminary findings evaluating the listening project protocol}}. {Front Pediatr}. 2014; 2: 80.
Auditory hypersensitivities are a common feature of autism spectrum disorder (ASD). In the present study, the effectiveness of a novel intervention, the listening project protocol (LPP), was evaluated in two trials conducted with children diagnosed with ASD. LPP was developed to reduce auditory hypersensitivities. LPP is based on a theoretical « neural exercise » model that uses computer altered acoustic stimulation to recruit the neural regulation of middle ear muscles. Features of the intervention stimuli were informed by basic research in speech and hearing sciences that has identified the specific acoustic frequencies necessary to understand speech, which must pass through middle ear structures before being processed by other components of the auditory system. LPP was hypothesized to reduce auditory hypersensitivities by increasing the neural tone to the middle ear muscles to functionally dampen competing sounds in frequencies lower than human speech. The trials demonstrated that LPP, when contrasted to control conditions, selectively reduced auditory hypersensitivities. These findings are consistent with the polyvagal theory, which emphasizes the role of the middle ear muscles in social communication.
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9. Righi G, Tierney AL, Tager-Flusberg H, Nelson CA. {{Functional connectivity in the first year of life in infants at risk for autism spectrum disorder: an EEG study}}. {PLoS One}. 2014; 9(8): e105176.
In the field of autism research, recent work has been devoted to studying both behavioral and neural markers that may aide in early identification of autism spectrum disorder (ASD). These studies have often tested infants who have a significant family history of autism spectrum disorder, given the increased prevalence observed among such infants. In the present study we tested infants at high- and low-risk for ASD (based on having an older sibling diagnosed with the disorder or not) at 6- and 12-months-of-age. We computed intrahemispheric linear coherence between anterior and posterior sites as a measure of neural functional connectivity derived from electroencephalography while the infants were listening to speech sounds. We found that by 12-months-of-age infants at risk for ASD showed reduced functional connectivity compared to low risk infants. Moreover, by 12-months-of-age infants later diagnosed with ASD showed reduced functional connectivity, compared to both infants at low risk for the disorder and infants at high risk who were not later diagnosed with ASD. Significant differences in functional connectivity were also found between low-risk infants and high-risk infants who did not go onto develop ASD. These results demonstrate that reduced functional connectivity appears to be related to genetic vulnerability for ASD. Moreover, they provide further evidence that ASD is broadly characterized by differences in neural integration that emerge during the first year of life.
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10. Tordjman S, Somogyi E, Coulon N, Kermarrec S, Cohen D, Bronsard G, Bonnot O, Weismann-Arcache C, Botbol M, Lauth B, Ginchat V, Roubertoux P, Barburoth M, Kovess V, Geoffray MM, Xavier J. {{Gene x Environment interactions in autism spectrum disorders: role of epigenetic mechanisms}}. {Front Psychiatry}. 2014; 5: 53.
Several studies support currently the hypothesis that autism etiology is based on a polygenic and epistatic model. However, despite advances in epidemiological, molecular and clinical genetics, the genetic risk factors remain difficult to identify, with the exception of a few chromosomal disorders and several single gene disorders associated with an increased risk for autism. Furthermore, several studies suggest a role of environmental factors in autism spectrum disorders (ASD). First, arguments for a genetic contribution to autism, based on updated family and twin studies, are examined. Second, a review of possible prenatal, perinatal, and postnatal environmental risk factors for ASD are presented. Then, the hypotheses are discussed concerning the underlying mechanisms related to a role of environmental factors in the development of ASD in association with genetic factors. In particular, epigenetics as a candidate biological mechanism for gene x environment interactions is considered and the possible role of epigenetic mechanisms reported in genetic disorders associated with ASD is discussed. Furthermore, the example of in utero exposure to valproate provides a good illustration of epigenetic mechanisms involved in ASD and innovative therapeutic strategies. Epigenetic remodeling by environmental factors opens new perspectives for a better understanding, prevention, and early therapeutic intervention of ASD.
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11. Zhang J, Wang A, Li Y, Lu X, Wang F, Fang F. {{Association of NCAM1 Polymorphisms with Autism and Parental Age at Conception in Chinese Han Population}}. {Genet Test Mol Biomarkers}. 2014.
Aims: The neural cell adhesion molecule (NCAM) has been reported to be involved in the development of the central nervous system and its mRNA level might decrease in the serum of autistic patients. However, there was no evidence of the association of the NCAM1 gene polymorphisms with autism. In the present study, we enrolled 237 children with autism and 451 healthy control subjects. Then, we used the direct DNA sequencing for genotyping five tag single-nucleotide polymorphisms (SNPs) in the NCAM1 gene. Results: By using case-control association analyses, we found that three SNPs at the NCAM1 gene were associated with autism (rs4937786, p=0.015; rs12418058, p=0.0076; rs1436109, p=0.0023). Two of them remained significant after the Bonferroni multiple testing correction (rs12418058, pcorrcted=0.038; rs1436109, pcorrcted=0.012). Moreover, two of the SNPs were associated with the parental age at conception in autism (rs12418058, p=0.037; rs1436109, p=0.01). Conclusion: These results showed that NCAM1 might play an important role in the pathogenesis of autism.
