1. Akins MR, Leblanc HF, Stackpole EE, Chyung E, Fallon JR. {{Systematic mapping of Fragile X granules in the developing mouse brain reveals a potential role for presynaptic FMRP in sensorimotor functions}}. {J Comp Neurol};2012 (Apr 23)
Loss of Fragile X mental retardation protein (FMRP) leads to Fragile X syndrome (FXS), the most common form of inherited intellectual disability and autism. Although the functions of FMRP and its homologues FXR1P and FXR2P are well studied in the somatodendritic domain, recent evidence suggests that this family of RNA binding proteins also plays a role in the axonal and presynaptic compartments. Fragile X granules (FXGs) are morphologically- and genetically-defined structures containing Fragile X proteins that are expressed axonally and presynaptically in a subset of circuits. To further understand the role of presynaptic Fragile X proteins in the brain we have systematically mapped the FXG distribution in the mouse central nervous system. This analysis revealed both the circuits and the neuronal types that express FXGs. FXGs are enriched in circuits that mediate sensory processing and motor planning – functions that are particularly perturbed in FXS patients. Analysis of FXG expression in the hippocampus suggests that CA3 pyramidal neurons utilize presynaptic Fragile X proteins to modulate recurrent but not feedforward processing. Neuron-specific FMRP mutants revealed a requirement for neuronal FMRP in the regulation of FXGs. Finally, conditional FMRP ablation demonstrated that FXGs are expressed in axons of thalamic relay nuclei that innervate cortex, but not in axons of thalamic reticular nuclei, striatal nuclei, or cortical neurons that innervate thalamus. Together, these findings support the proposal that dysregulation of axonal and presynaptic Fragile X proteins contribute to the neurological symptoms of FXS. J. Comp. Neurol., 2012. (c) 2012 Wiley-Liss, Inc.
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2. Amitai M, Peskin M, Gothelf D, Zalsman G. {{[Autism spectrum disorders: updates and new definitions]}}. {Harefuah};2012 (Mar);151(3):167-170, 188.
Autism spectrum disorders (ASD) include several clinically different disorders. Despite the impression that in recent years there has been a rise in the incidence of this disorder, it seems that the apparent rise stems from the widening of diagnostic criteria rather than from a true rise in disorder incidence. Notwithstanding the wide range of clinical symptoms, reliabLe information on the etiology of this disorder is lacking. However, new data points to an important genetic component and to structural changes in the brain. There is a wide range of comorbidities with additional neurodevelopmental disorders. The currently offered treatment is multi-disciplinary and includes primarily behavioral therapy and symptomatic treatment with psychotropic drugs.
3. Bennett E, Heaton P. {{Is Talent in Autism Spectrum Disorders Associated with a Specific Cognitive and Behavioural Phenotype?}}. {J Autism Dev Disord};2012 (Apr 24)
Parents of 125 children, adolescents and young adults with autism spectrum disorders completed a newly developed questionnaire aimed at identifying cognitive and behavioural characteristics associated with savant skills in this group. Factors distinguishing skilled individuals were then further investigated in case studies of three individuals with exceptional skills for music, art and mathematics. The findings from the case studies largely confirmed the results from the questionnaire study in showing that special skills are associated with superior working memory and highly focused attention that is not associated with increased obsessesionality. Although intellectual impairment and a local bias have been widely associated with special skills in the savant literature, neither the screening nor case studies provided strong evidence for such associations.
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4. Dundas E, Gastgeb H, Strauss MS. {{Left Visual Field Biases when Infants Process Faces: A Comparison of Infants at High- and Low-Risk for Autism Spectrum Disorder}}. {J Autism Dev Disord};2012 (Apr 24)
While it is well-known that individuals with autism spectrum disorder (ASD) have difficulties processing faces, very little is known about the origins of these deficits. The current study focused on 6- and 11-month-old infants who were at either high-risk (n = 43) or low-risk (n = 31) for developing ASD based on having a sibling already diagnosed with the disorder. Eye-tracking data were collected while the infants viewed color photographs of faces. Similar to previous studies with both typically developing adults and infants, low-risk infants demonstrated a preference for looking at the left side of the face (known as a left visual field bias) that emerged by 11 months of age. In contrast, high-risk infants did not demonstrate a left visual field bias at either age. Comparisons of the amount of attention given to the eye versus mouth regions indicated no differences between the two risk groups.
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5. El-Ansary AK, Ben Bacha A, Kotb M. {{Etiology of autistic features: the persisting neurotoxic effects of propionic acid}}. {J Neuroinflammation};2012 (Apr 24);9(1):74.
ABSTRACT: BACKGROUND: Recent clinical observations suggest that certain gut and dietary factors may transiently worsen symptoms in autism. Propionic acid (PA) is a short chain fatty acid and an important intermediate of cellular metabolism. Although PA has several beneficial biological effects, its accumulation is neurotoxic. METHODS: Two groups of young Western albino male rats weighing about 45 to 60 grams (approximately 21 days old) were used in the present study. The first group consisted of oral buffered PA-treated rats that were given a neurotoxic dose of 250 mg/kg body weight/day for three days, n = eight; the second group of rats were given only phosphate buffered saline and used as a control. Biochemical parameters representing oxidative stress, energy metabolism, neuroinflammation, neurotransmission, and apoptosis were investigated in brain homogenates of both groups. RESULTS: Biochemical analyses of brain homogenates from PA-treated rats showed an increase in oxidative stress markers (for example, lipid peroxidation), coupled with a decrease in glutathione (GSH) and glutathione peroxidase (GPX) and catalase activities. Impaired energy metabolism was ascertained through the decrease of lactate dehydrogenase and activation of creatine kinase (CK). Elevated IL-6, TNFalpha, IFNgamma and heat shock protein 70 (HSP70) confirmed the neuroinflammatory effect of PA. Moreover, elevation of caspase3 and DNA fragmentation proved the pro-apoptotic and neurotoxic effect of PA to rat pups CONCLUSION: By comparing the results obtained with those from animal models of autism or with clinical data on the biochemical profile of autistic patients, this study showed that the neurotoxicity of PA as an environmental factor could play a central role in the etiology of autistic biochemical features.
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6. Jacot-Descombes S, Uppal N, Wicinski B, Santos M, Schmeidler J, Giannakopoulos P, Heinsen H, Schmitz C, Hof PR. {{Erratum to: Decreased pyramidal neuron size in Brodmann areas 44 and 45 in patients with autism}}. {Acta Neuropathol};2012 (Apr 24)
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7. Kocovska E, Fernell E, Billstedt E, Minnis H, Gillberg C. {{Vitamin D and autism: Clinical review}}. {Res Dev Disabil};2012 (Apr 20);33(5):1541-1550.
BACKGROUND: Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with multiple genetic and environmental risk factors. The interplay between genetic and environmental factors has become the subject of intensified research in the last several years. Vitamin D deficiency has recently been proposed as a possible environmental risk factor for ASD. OBJECTIVE: The aim of the current paper is to systematically review the research regarding the possible connection between ASD and vitamin D, and to provide a narrative review of the literature regarding the role of vitamin D in various biological processes in order to generate hypotheses for future research. RESULTS: Systematic data obtained by different research groups provide some, albeit very limited, support for the possible role of vitamin D deficiency in the pathogenesis of ASD. There are two main areas of involvement of vitamin D in the human body that could potentially have direct impact on the development of ASD: (1) the brain (its homeostasis, immune system and neurodevelopment) and (2) gene regulation. CONCLUSION: Vitamin D deficiency – either during pregnancy or early childhood – may be an environmental trigger for ASD in individuals genetically predisposed for the broad phenotype of autism. On the basis of the results of the present review, we argue for the recognition of this possibly important role of vitamin D in ASD, and for urgent research in the field.
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8. Lin PI, Chien YL, Wu YY, Chen CH, Gau SS, Huang YS, Liu SK, Tsai WC, Chiu YN. {{The WNT2 gene polymorphism associated with speech delay inherent to autism}}. {Res Dev Disabil};2012 (Apr 19);33(5):1533-1540.
Previous evidence suggests that language function is modulated by genetic variants on chromosome 7q31-36. However, it is unclear whether this region harbors loci that contribute to speech delay in autism. We previously reported that the WNT2 gene located on 7q31 was associated with the risk of autism. Additionally, two other genes on 7q31-36, FOXP2 and the EN2 genes are also found to play a role in language impairment. Therefore, we hypothesize that the WNT2 gene, FOXP2 gene, and EN2 gene, may act in concert to influence language development in the same population. A total of 373 individuals diagnosed with autistic disorder were recruited in the current study. We selected 6 tag single nucleotide polymorphisms (SNPs) within the WNT2 gene, 3 tag SNPs in the FOXP2, and 3 tag SNPs in the EN2 genes, to study the effect of these genes on language development. Age of first phrase was treated as a quantitative trait. We used general linear model to assess the association between speech delay and these variants. The results show that rs2896218 in the WNT2 gene was moderately significantly associated with age of first phrase (permutation p=0.0045). A three-locus haplotype in the WNT2 gene was significantly associated with age of first phrase (permutation p=2×10(-4)). Furthermore, we detected an interaction effect on age of first phrase between a SNP rs2228946 in the WNT2 gene and another SNP rs6460013 in the EN2 gene (p=0.0012). Therefore, the WNT2 gene may play a suggestive role in language development in autistic disorder. Additionally, the WNT2 gene and EN2 gene may act in concert to influence the language development in autism.
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9. Ludlow AK, Taylor-Whiffen E, Wilkins AJ. {{Coloured filters enhance the visual perception of social cues in children with autism spectrum disorders}}. {ISRN Neurol};2012;2012:298098.
Coloured filters have been found to reduce visual distortion of text in children with autism spectrum disorders (ASD). We investigated the effect of the overlays on the « mind in the eye » task in children with ASD and controls matched for age, gender, and nonverbal IQ. Children were shown photographs of the periocular region of various faces and were asked to judge which emotion was being expressed in the eyes. In children with ASD, the perception of the emotion was significantly improved when the photograph was covered by a coloured overlay. The improvement was significantly greater than in the controls, who showed no significant effect of the overlay. A perceptual impairment may contribute to the social difficulties shown in ASD.
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10. Main PA, Angley MT, O’Doherty CE, Thomas P, Fenech M. {{The potential role of the antioxidant and detoxification properties of glutathione in autism spectrum disorders: a systematic review and meta-analysis}}. {Nutr Metab (Lond)};2012 (Apr 24);9(1):35.
ABSTRACT: BACKGROUND: Glutathione has a wide range of functions; it is an endogenous anti-oxidant and plays a key role in the maintenance of intracellular redox balance and detoxification of xenobiotics. Several studies have indicated that children with autism spectrum disorders may have altered glutathione metabolism which could play a key role in the condition. METHODS: A systematic literature review and meta-analysis was conducted of studies examining metabolites, interventions and/or genes of the glutathione metabolism pathways i.e. the gamma-glutamyl cycle and trans-sulphuration pathway in autism spectrum disorders. RESULTS: Thirty nine studies were included in the review comprising an in vitro study, thirty two metabolite and/or co-factor studies, six intervention studies and six studies with genetic data as well as eight studies examining enzyme activity. CONCLUSIONS: The review found evidence for the involvement of the gamma-glutamyl cycle and trans-sulphuration pathway in autistic disorder is sufficiently consistent, particularly with respect to the glutathione redox ratio, to warrant further investigation to determine the significance in relation to clinical outcomes. Large, well designed intervention studies that link metabolites, cofactors and genes of the gamma-glutamyl cycle and trans-sulphuration pathway with objective behavioural outcomes in children with autism spectrum disorders are required. Future risk factor analysis should include consideration of multiple nutritional status and metabolite biomarkers of pathways linked with the gamma-glutamyl cycle and the interaction of genotype in relation to these factors.
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11. Mandell D. {{Autism. Editorial}}. {Autism};2012 (Mar);16(2):105-106.
12. Millikovsky-Ayalon M, Sofrin R, Raz R, Shilon-Hadass A, Yehuda M, Mukamel M, Gabis LV. {{[Preschool diagnostic process and changes in diagnosis of autism spectrum disorder]}}. {Harefuah};2012 (Mar);151(3):150-154, 190.
BACKGROUND: Autism spectrum disorders [ASD] are characterized by a wide range of neuropsychiatric comorbid disorders which change during early development. Coordinated collaboration between therapists from various disciplines and integrating measurements, may Lead to a comprehensive diagnosis of ASD. A diagnostic kindergarten set-up for children with a preliminary diagnosis of ASD or communication disorder can facilitate a multidisciplinary diagnosis, as an integral part of the child and parental intervention process. GOALS: To examine the changes in the diagnosis of children after one year of observation and treatment in a special education set-up, including aspects such as common neuropsychiatric comorbidity, differential diagnosis and subsequent placement recommendations. METHODS: Changes in the frequencies of ASD diagnoses were calculated prior to and following participation in the kindergarten for 76 children, who studied in the diagnostic kindergarten for ASD at the Weinberg Child Development Center during the last decade. Frequencies of neuropsychiatric comorbid disorders and differential diagnosis were calculated. RESULTS: It was found that: half (44.7%) of the preliminary diagnoses changed after a year of treatment; 14.2% of the children admitted with other developmental diagnoses, were subsequently diagnosed with ASD and in the cases of 25% of the children with ASD, their diagnosis was removed. Neuropsychiatric comorbid disorders appeared in 66% of cases. The most common differential diagnosis was Language disability, which appeared in 76% of the cases. CONCLUSIONS: This study reinforces the importance of a thorough assessment process conducted by a multidisciplinary team during and after treatment. A quarter of the children diagnosed with ASD in early childhood may have a different diagnosis later, usually milder, probably as a consequence of developmental changes combined with intensive treatment.
13. Park CJ, Yelland GW, Taffe JR, Gray KM. {{Brief Report: The Relationship Between Language Skills, Adaptive Behavior, and Emotional and Behavior Problems in Pre-schoolers with Autism}}. {J Autism Dev Disord};2012 (Apr 24)
This study investigated the relationship between structural language skills, and communication skills, adaptive behavior, and emotional and behavior problems in pre-school children with autism. Participants were aged 3-5 years with autism (n = 27), and two comparison groups of children with developmental delay without autism (n = 12) and typically developing children (n = 20). The participants were administered standardised tests of structural language skills, and parents completed the Vineland Adaptive Behavior Scales and the Developmental Behaviour Checklist. Results indicated that for children with autism, communication skills, and in particular receptive communication skills, were associated with social and daily living skills, and behavior problems. Receptive structural language skills were associated with expressive communication skills. There were no associations found between structural language skills and social or daily living skills, nor behavior problems. The results of this study suggest that communication skills are more closely linked to functional and behavioral outcomes in autism than structural language skills.
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14. Pepin G, Stagnitti K. {{Come play with me: an argument to link autism spectrum disorders and anorexia nervosa through early childhood pretend play}}. {Eat Disord};2012 (May);20(3):254-259.
This article builds on the argument of a link between behaviours observed in persons with autism spectrum disorders and persons with anorexia nervosa. In describing these behaviours, a link is made between deficits in social cognition, lack of flexible and creative thinking, theory of mind, and deficits in early pretend play ability. Early pretend play ability is a strong avenue to the development and strengthening of social cognition, problem solving, language, logical sequential thought, and understanding social situations. Currently, there is no literature on the pretend play ability of persons who develop anorexia nervosa. This article argues for research into this area which may potentially contribute to developments in new intervention strategies for these persons.
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15. Rai K, Hegde AM, Jose N. {{Salivary antioxidants and oral health in children with autism}}. {Arch Oral Biol};2012 (Apr 20)
Individuals with autism vary widely in abilities, intelligence, and behaviours. Autistic children have preferences for soft and sweetened food making them susceptible to caries. A wide spectrum of medical and behavioural symptoms is exhibited by children with autism, which makes routine dental care very difficult in them. Mental retardation is evident in approximately 70% of individuals with autism and most psychiatric disorders including autism are associated with increased oxidative stress. OBJECTIVES: To evaluate the oral health status of children with autism and to determine the salivary pH and total salivary antioxidant concentration (TAC). MATERIALS AND METHODS: 101 subjects with autism between age group of 6 and 12 year were part of the study and 50 normal healthy siblings of same age group were taken as control group. Oral health status was analysed using oral hygiene index-simplified and dentition status index. The salivary total anti-oxidant level was estimated using phosphomolybdic acid using spectrophotometric method and the salivary pH using the pH indicating paper. The results were statistically analyzed using Mann-Whitney U test. RESULTS: A statistically very highly significant difference was seen in the mean oral hygiene index scores (autistic group – 1.2 and control group – 1, P<0.001) and the mean salivary total antioxidant concentration (autistic group – 5.7mug/ml and control group – 38mug/ml, P<0.001). No statistical significant difference was observed in the dental caries status and the salivary pH of autistic group and the control group. CONCLUSIONS: Similar dental caries status was observed in children with autism and their healthy normal siblings. Oral hygiene was poor in children with autism whereas the Salivary TAC was significantly reduced in autistic children.
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16. Rumpf AL, Kamp-Becker I, Becker K, Kauschke C. {{Narrative competence and internal state language of children with Asperger Syndrome and ADHD}}. {Res Dev Disabil};2012 (Apr 19);33(5):1395-1407.
The central question of the present study was whether there are differences between children with Asperger Syndrome (AS), children with attention deficit hyperactivity disorder (ADHD) and healthy controls (HC) with respect to the organization of narratives and their verbalization of internal states. Oral narrations of a wordless picture book produced by 31 children (11 with AS, 9 with ADHD, 11 HC, aged 8-12) were analyzed regarding the following linguistic variables: story length, sentence structure and sentence complexity, coherence and cohesion of the stories, verbalization of the narrator’s perspective, as well as internal state language (verbal reference to mental states). Considerable similarities were noted between the two clinical groups, which deviate from HC children. Narratives of the children with AS and ADHD were shorter than the narratives produced by the HC children. The children of both clinical groups failed to point out the main aspects of the story. In particular, children with AS did not refer to cognitive states as often as the other groups. With respect to narrative coherence, they produced fewer pronominal references than HC children and children with ADHD. In conclusion, the two clinical groups differed from the HC group on a number of features, and a less frequent reference to cognitive states was identified for the children with AS.
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17. Shih CH. {{A finger-pressing position detector for assisting people with developmental disabilities to control their environmental stimulation through fine motor activities with a standard keyboard}}. {Res Dev Disabil};2012 (Apr 20);33(5):1360-1365.
This study used a standard keyboard with a newly developed finger-pressing position detection program (FPPDP), i.e. a new software program, which turns a standard keyboard into a finger-pressing position detector, to evaluate whether two people with developmental disabilities would be able to actively perform fine motor activities to control their preferred environmental stimulation. An ABAB design was adopted in this study. The data showed that both participants’ target responses (i.e. fine motor activities) significantly increased (i.e. they performed more fine motor activities to activate the environmental stimulation) during the intervention phases. The practical and developmental implications of the findings are discussed.
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18. Taylor MA, Schreck KA, Mulick JA. {{Sleep disruption as a correlate to cognitive and adaptive behavior problems in autism spectrum disorders}}. {Res Dev Disabil};2012 (Apr 19);33(5):1408-1417.
Sleep problems associated with autism spectrum disorders (ASD) have been well documented, but less is known about the effects of sleep problems on day-time cognitive and adaptive performance in this population. Children diagnosed with autism or pervasive developmental disorder-not otherwise specified (PDD-NOS) (N=335) from 1 to 10 years of age (M=5.5 years) were evaluated for the relationships of Behavioral Evaluation of Disorders of Sleep (BEDS; Schreck, 1998) scores to measures of intelligence and adaptive behavior. Results suggested that children who slept fewer hours per night had lower overall intelligence, verbal skills, overall adaptive functioning, daily living skills, socialization skills, and motor development. Children who slept fewer hours at night with waking during the night had more communication problems. Breathing related sleep problems and fewer hours of sleep related most often to problems with perceptual tasks. The results indicate that quality of sleep – especially sleep duration – may be related to problems with day-time cognitive and adaptive functioning in children with autism and PDD-NOS. However, future research must be conducted to further understand these relationships.
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19. Uno Y, Uchiyama T, Kurosawa M, Aleksic B, Ozaki N. {{The combined measles, mumps, and rubella vaccines and the total number of vaccines are not associated with development of autism spectrum disorder: The first case-control study in Asia}}. {Vaccine};2012 (Apr 20)
OBJECTIVE: The aim of this study was to investigate the relationship between autism spectrum disorder (ASD) and general vaccinations, including measles-mumps-rubella (MMR) vaccine, in Japanese subjects, a population with high genetic homogeneity. PATIENTS AND METHODS: A case-control study was performed. Cases (n=189) were diagnosed with ASD, while controls (n=224) were volunteers from general schools, matched by sex and birth year to cases. Vaccination history and prenatal, perinatal, and neonatal factors from the Maternal and Child Health handbook, which was part of each subject’s file, were examined. To determine the relationship between potential risk factors and ASD, crude odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated, and the differences in mean values of the quantitative variables between cases and controls were analyzed using an unpaired t-test. Moreover, MMR vaccination and the effect of the number of vaccine injections were investigated using a conditional multiple regression model. RESULTS: For MMR vaccination, the OR was 1.04 (95% CI, 0.65-1.68), and no significant differences were found for the other vaccines. For all of the prenatal, perinatal and neonatal factors, there were no significant differences between cases and controls. Furthermore, regarding the presence of ASD, MMR vaccination and the number of vaccine injections had ORs of 1.10 (95% CI, 0.64-1.90) and 1.10 (95% CI, 0.95-1.26), respectively, in the conditional multiple regression model; no significant differences were found. CONCLUSIONS: In this study, there were not any convincing evidences that MMR vaccination and increasing the number of vaccine injections were associated with an increased risk of ASD in a genetically homogeneous population. Therefore, these findings indicate that there is no basis for avoiding vaccination out of concern for ASD.
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20. Vernon TW, Koegel RL, Dauterman H, Stolen K. {{An Early Social Engagement Intervention for Young Children with Autism and their Parents}}. {J Autism Dev Disord};2012 (Apr 24)
The social vulnerabilities associated with young children with autism are recognized as important intervention targets due to their influence on subsequent development. Current research suggests that interventions that combine motivational and social components can create meaningful changes in social functioning. Simultaneously, it is hypothesized that parent delivery of such strategies can invoke increases in these core social behaviors and parent engagement. This study examined the effects of teaching parents to implement a social engagement intervention with their children. The results indicated that the use of this parent-delivered social intervention led to (a) increases in their children’s use of eye contact, directed positive affect, and verbal initiations, (b) increases in parent positive affect and synchronous engagement, and (c) generalized increases in parent and child behaviors.
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21. Williams EL, Casanova MF. {{Above genetics: lessons from cerebral development in autism}}. {Transl Neurosci};2011 (Jun 1);2(2):106-120.
While a distinct minicolumnar phenotype seems to be an underlying factor in a significant portion of cases of autism, great attention is being paid not only to genetics but to epigenetic factors which may lead to development of the conditions. Here we discuss the indivisible role the molecular environment plays in cellular function, particularly the pivotal position which the transcription factor and adhesion molecule, beta-catenin, occupies in cellular growth. In addition, the learning environment is not only integral to postnatal plasticity, but the prenatal environment plays a vital role during corticogenesis, neuritogenesis, and synaptogenesis as well. To illustrate these points in the case of autism, we review important findings in genetics studies (e.g., PTEN, TSC1/2, FMRP, MeCP2, Neurexin-Neuroligin) and known epigenetic factors (e.g., valproic acid, estrogen, immune system, ultrasound) which may predispose towards the minicolumnar and connectivity patterns seen in the conditions, showing how one-gene mutational syndromes and exposure to certain CNS teratogens may ultimately lead to comparable phenotypes. This in turn may shed greater light on how environment and complex genetics combinatorially give rise to a heterogenetic group of conditions such as autism.
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22. Xinyuanhe C, Portera-Cailliau C. {{The trouble with spines in fragile X syndrome: density, maturity and plasticity}}. {Neuroscience};2012 (Apr 19)
Dendritic spines are the principal recipients of excitatory synaptic inputs and the basic units of neural computation in the mammalian brain. Alterations in the density, size, shape, turnover of mature spines, or defects in how spines are generated and establish synapses during brain development, could all result in neuronal dysfunction and lead to cognitive and/or behavioral impairments. That spines are abnormal in fragile X syndrome (FXS) and in the best-studied animal model of this disorder, the Fmr1 knockout mouse, is an undeniable fact. But the troublewith spines in FXS is that the exact nature of their defect is still controversial. Here, we argue that the most consistent abnormality of spines in FXS may be a subtle defect in activity-dependent spine plasticity and maturation. We also propose some future directions for research into spine plasticity in FXS at the cellular and ultrastructural levelsthat could helpsolve a two-decade-long riddle about the integrity of synapses in this prototypical neurodevelopmental disorder.
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23. Zachor DA. {{[Autism spectrum disorders–a syndrome on the rise: risk factors and advances in early detection and intervention]}}. {Harefuah};2012 (Mar);151(3):162-164, 189.
Autism spectrum disorders [ASD] are complex neurobehavioraL disorders defined by social and communication deficits and repetitive and stereotyped behaviors. The current estimated prevalence of ASD is approximately 1:100, which reflects a 15-fold increase from studies published a half-century ago. ASD is a highly heritable disorder, however, the exact cause of ASD is still unknown. ASD is associated with altered functional and structural connectivity patterns in the frontal and temporo-limbic brain regions that occur early in life. It is now believed that environmental factors may modulate phenotypical expression of ASD that are associated with the genetic predisposition. Several possible risk factors for ASD were investigated and included advanced parental age, birth complications, prematurity, Low birth weight and assisted conception. Numerous epidemioLogical reports have failed to confirm any association between immunizations and MMR specifically or thimerosaL exposure and risk for ASD. The diagnosis of ASD can be reLiably made in the second year of Life and appears to be relatively stable over time. However, diagnosis of very young children can be quite complex due to their clinical heterogeneity and varying patterns of onset that can differ from the typical autism symptoms of an older child. It is further challenging to distinguish between developmental and/or speech delay and ASD at this early age. Standardized tests for ASD diagnosis, developmental level and adaptive skiLls have been successfully used for accurate diagnosis of ASD. Research has recently focused on possible basic measures and/or biological markers that can assist with early diagnosis of ASD. Recent studies suggest that substantial gains can be achieved by intensive behavioral intervention initiated prior to 24 months, as neural plasticity is increased and chaLLenging behaviors are less prominent. Effective early intervention should begin soon after the diagnosis is made, and be individualized, intensive, and comprehensive and should include parent education, and behavioral intervention. It is highly important for pediatricians and experts in child neurology, development and child psychiatry to recognize the early signs of ASD, diagnostic tools and effective intervention methods.
