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Course of autism signs in the first year of life.

Autism spectrum disorders (ASD) are thought to be present right from birth, even if a minority of children displays a normal course during infancy followed by a regression during the second year of life. However, established criteria are not yet available to differentiate these different courses of ASD, and data coming from different sources have not yet been organized into a clear definition. The aim of this study was to elucidate the time of onset, as well as type, frequency and stability of symptoms during the first year of life in ASD. The behavioral summarized evaluation scale, applied to 40 home movies of children later diagnosed as having ASD, showed that most of the subjects (87.5%) display symptoms within the first year of life, when only a small group (12.5%) is completely symptom free. A group of more rated symptoms was found, constituting a typical pattern characterized by being withdrawn, and displaying poor social initiative, hypoactivity, and lack of emotional modulation. The importance of these findings is discussed in relation to early diagnosis and treatment.

Affective Symptoms↗

Double Genetic Diagnosis Involving MECP2 and EPHB4 in a Child with Neurodevelopmental Delay and Vascular Anomalies: A Case Report.

BACKGROUND: Double genetic diagnoses are increasingly identified with the advent of genome-wide sequencing techniques. While MECP2 mutations are associated with Rett syndrome and EPHB4 mutations with vascular malformation syndromes, their co-occurrence has not been previously described. CASE PRESENTATION: We describe an 8-year-and-2-month-old girl presenting with global developmental delay, autism spectrum disorder, and stereotypic behaviors, along with multiple well-demarcated cutaneous vascular lesions. Although she had no clinical seizures, electroencephalogram revealed epileptiform discharges. Physical examination showed dysmorphic features and vascular anomalies, including telangiectatic pink-to-red macular vascular lesions. Whole exome sequencing (WES) identified two de novo heterozygous pathogenic variants: a missense mutation in MECP2 (c.433C>T; p.Arg145Cys), a gene classically implicated in Rett syndrome, and a nonsense mutation in EPHB4 (c.1093C>T; p.Arg365Ter), which has been previously associated with capillary malformation-arteriovenous malformation syndrome type 2. The neurodevelopmental findings, while consistent with the broader spectrum of MECP2-related disorders, along with coexisting vascular anomalies, were best accounted for by a dual genetic diagnosis involving both MECP2 and EPHB4. CONCLUSION: This case underscores the diagnostic value of considering dual genetic diagnoses in patients with complex phenotypes and highlights the role of WES in uncovering multilocus variation, thereby expanding the known phenotypic spectrum associated with MECP2 and EPHB4 mutations.

Double genetic diagnosis↗

Autism in several members of a family with generalized epilepsy with febrile seizures plus.

The neurobiologic basis for autism is not well understood. In contrast, there have been several recent discoveries into the genetics of generalized epilepsy with febrile seizures plus, a group of epilepsy syndromes characterized by multiple seizure phenotypes. Here we describe a family with generalized epilepsy with febrile seizures plus and variably expressed autism spectrum disorder that does not show linkage to any of the four known generalized epilepsy with febrile seizures plus loci. A relationship between these two disorders has not previously been described.

Adult↗

Oromotor and communication findings in joubert syndrome: further evidence of multisystem apraxia.

This study provides descriptive information in the areas of oromotor abilities and communication to better understand the spectrum of disability in individuals with Joubert syndrome. Participants included 21 individuals with the diagnosis of Joubert syndrome (mean age 10.45 years). Participants completed oromotor and receptive language measures. In addition, all of the participants' speech and gesture communication from a narrative task was coded and analyzed from videotape. Caregivers reported the participants' level of fine and gross motor function. The results show that individuals with Joubert syndrome exhibit a distinct oromotor pattern consistent with verbal and lingual apraxias. Despite significant motor skills deficits and oculomotor apraxia, persons with Joubert syndrome produced gestures when communicating, and those whose speech was less intelligible used a higher rate of gesture compared with those with greater verbal output. These findings suggest a new form of apraxia not previously described in the condition and are consistent with previous research that suggests that persons with Joubert syndrome typically do not exhibit classic symptoms of autism spectrum disorder.

Adolescent↗

Labels increase attention to novel objects in children with autism and comprehension-matched children with typical development.

This study used an intact group comparison to examine attention following in 34 children aged 2 years diagnosed with autism spectrum disorder (ASD) matched pairwise for vocabulary comprehension with a group of typically developing toddlers. For both groups of children, the presence of verbal labels during a referential task increased attention to a novel object over and above the attention-facilitating effect of child-directed talking without labeling. The typically developing children displayed more attention following than comprehension matched children with ASD across experimental conditions and there was no significant difference between the groups in the facilitative effect of hearing verbal labels. Implications for word-learning theory, intervention strategies and future research are considered.

Attention↗

Theory of mind and central coherence in adults with high-functioning autism or Asperger syndrome.

The study investigated theory of mind and central coherence abilities in adults with high-functioning autism (HFA) or Asperger syndrome (AS) using naturalistic tasks. Twenty adults with HFA/AS correctly answered significantly fewer theory of mind questions than 20 controls on a forced-choice response task. On a narrative task, there were no differences in the proportion of mental state words between the two groups, although the participants with HFA/AS were less inclined to provide explanations for characters' mental states. No between-group differences existed on the central coherence questions of the forced-choice response task, and the participants with HFA/AS included an equivalent proportion of explanations for non-mental state phenomena in their narratives as did controls. These results support the theory of mind deficit account of autism spectrum disorders, and suggest that difficulties in mental state attribution cannot be exclusively attributed to weak central coherence.

Adult↗

Effects of temperament, symptom severity and level of functioning on maternal stress in Greek children and youth with ASD.

This study examined the effect of child temperament, symptom severity, verbal ability and level of functioning on maternal stress in 43 Greek mothers of children and young people with autism spectrum disorder. Symptom severity was assessed by the CARS, level of functioning by the PEP, temperament by the Dimensions of Temperament Scale (DOTS-R) and maternal stress by the Clarke Modification of Holroyd's Questionnaire on Resources and Stress (QRS). Lower-functioning children and those with high activity level, low flexibility and low mood scores were perceived to be more stressful. Counter to expectation, children with ASD who were rated high on rhythmicity and task orientation were perceived as more stressful. Best predictors of maternal stress were high activity level, low mood and high symptom severity. Mothers of non-verbal children were more stressed than those of verbal. The relevance of child temperament for understanding maternal stress is discussed with particular relevance to the Greek culture and available supports.

Adolescent↗

Altered ECM deposition and cell adhesion signaling in a human cortical organoid model of fragile X syndrome.

Fragile X Syndrome (FXS) is the most common inherited intellectual disability, and the most common monogenic cause of autism spectrum disorder (ASD). It is caused by epigenetic silencing of the FMR1 gene leading to the loss of FMRP, an RNA-binding protein that regulates local mRNA translation in neuronal dendrites, crucial for synapse development. Three-dimensional (3D) brain organoid models derived through in vitro differentiation of pluripotent stem cells offer a powerful tool to dissect the underlying mechanisms of neurodevelopmental disorders. Here, we generated human FXS and control organoids using isogenic human embryonic stem cell clones with and without the FXS mutation. Our results show that mature FXS cortical brain organoids can be derived by inhibiting the TGFβ and Wnt pathways. Moreover, expression analyses including immunofluorescence, qRT-PCR, proteomics and western blotting reveal altered levels of neuronal markers and ECM deposition along with modulated downstream signaling molecules. Interestingly, in silico analysis of proteomics revealed several altered pathways, such as cell adhesion, regulation of neurogenesis and cell cycle that are implicated in FXS. Collectively, our unique FXS-organoids derived from isogenic hESC lines may serve as a model for studying the pathology of FXS disorder and for developing therapeutical intervention.

Humans↗

Disambiguation and mapping of new word meanings by individuals with intellectual/ developmental disabilities.

Wilkinson and Green (1998) reported that differences in the procedure by which new words were introduced to learners with cognitive impairments significantly affected their accuracy in later tests of receptive understanding of word meanings. However, a limited sample and no control group rendered the data preliminary. Here, I replicated and extended the research. First, a control group of preschool children, matched on receptive vocabulary age, was compared to individuals with intellectual disability of unspecified origin. Second, performance was also evaluated in three matched groups of varying etiology: unspecified, Down syndrome, and autism spectrum disorders. Performance on receptive word matching differed between preschool children and their matched experimental groups as well as among matched etiological groups.

Child↗

Nicotinic cholinergic receptors in the rat cerebellum: multiple heteromeric subtypes.

Nicotinic receptors (nAChRs) in the cerebellum have been implicated in the pathology of autism spectrum disorders (Lee et al., 2002; Martin-Ruiz et al., 2004). The subtypes of nAChRs in the cerebellum are not known in any detail, except that, in addition to the homomeric alpha7 subtype, there appears to be one or more heteromeric subtypes consisting of combinations of alpha and beta subunits. To begin to better understand the potential roles of these heteromeric nAChRs in cerebellar circuitry and their potential as targets for nicotinic drugs, we investigated their subunit composition. Using subunit-selective antibodies in sequential immunoprecipitation assays, we detected six structurally distinct heteromeric nAChR populations in the rat cerebellum. Among these were several subtypes that have not been encountered previously, including alpha3alpha4beta2 and alpha3alpha4beta4 nAChRs. This diversity suggests that nAChRs play multiple roles in cerebellar physiology.

Analysis of Variance↗

Persistence of stereotypic behavior: examining the effects of external reinforcers.

Basic research has shown that behavioral persistence is often positively related to rate of reinforcement. This relation, expressed in the metaphor of behavioral momentum, has potentially important implications for clinical application. The current study examined one prediction of the momentum metaphor for automatically reinforced behavior. Participants were 3 children who had been diagnosed with an autism spectrum disorder and who engaged in stereotypic behavior maintained by automatic reinforcement. Results suggested that stereotypic behavior was more resistant to disruption following periods of access to preferred stimuli delivered on a variable-time schedule than following periods without access to preferred stimuli. The implications of these findings for the treatment of automatically reinforced behavior are discussed.

Attention↗

Generalization of tacting actions in children with autism.

This intervention compared the effects of two procedures on the generalization of a tacting repertoire (labeling) in 6 children with autism spectrum disorder. In one procedure the verbal antecedent stimulus "What is she doing?" appeared together with a person performing an action; in the other procedure, the antecedent stimulus was just the presence of the action. In initial tests, children emitted tacts only when the action was presented with the verbal antecedent. Thereafter, they learned to tact an action without the verbal antecedent and received tests to evaluate generalization to another action. Results indicated that in order to obtain generalization of tacting actions, it was necessary to learn to tact other actions without the verbal antecedent as well as learning to tact the action with the verbal antecedent. These findings have relevance for generalization of tacting actions from control by verbal antecedents to natural conditions and the production of spontaneous language.

Autistic Disorder↗

Genomic basis of developmental defects of enamel and sex-specific effects.

We conducted a multi-ancestry genome-wide association study (GWAS) of developmental defects of enamel (DDE) in the primary dentition among 6,061 U.S. preschool-aged children (3-5 years). We investigated four DDE phenotypes (demarcated opacities, diffuse opacities, hypoplastic defects, and a combined DDE trait) leveraging main-effect models, joint gene-sex interaction testing (2df), and sex-stratified analyses. SNP-based heritability for the combined DDE trait was estimated at 20%, with concordance analyses robustly supporting a genetic etiology. We identified 39 unique genome-wide significant loci (P<5&#xd7;10 ), with five surpassing a study-wide Bonferroni-corrected statistical significance criterion (P<1.25&#xd7;10 9), including Y RNA and ALDH1A1. The main-effect GWAS identified 20 loci, including HBS1L and MYB, genes regulating hematopoiesis with plausible roles in amelogenesis. Joint test and sex-stratified analyses revealed 19 additional loci, including ALDH1A1, TENM2, and DLGAP2, demonstrating sex-specific heterogeneity. Nineteen loci exhibited sex-specific differences after Bonferroni correction (P<2x10-3), including genes involved in retinoic acid signaling (ALDH1A1), odontogenesis (TENM2), and neurodevelopment (DLGAP2, CDH10). Pathway enrichment highlighted ectodermal and synapse organization networks, suggesting shared etiological mechanisms between DDE and systemic conditions like neurofibromatosis and autism spectrum disorder. Notably, no locus generalized in an external GWAS of permanent dentition DDE, underscoring fundamental biological differences in the genetic architectures governing primary versus permanent enamel formation. Crucially, a comprehensive cross-trait pleiotropy lookup against early childhood caries (ECC) revealed no shared genetic architecture, supporting the notion that the established clinical and epidemiological association between DDE and ECC is likely driven by structural defects increasing caries lesion susceptibility rather than genetic pleiotropy. By integrating gene-sex interaction testing, this study offers novel insights into the complex, sexually dimorphic genetic etiology of DDE and augments the biological evidence base that can support the development of precision pediatric dentistry.

developmental defects of enamel↗

[Child neuropsychiatric perspectives can contribute to understanding of social disadvantage].

At least five per cent of the general population of children suffer from severe neuropsychiatric impairment. Autism spectrum disorders, ADHD/DAMP, Tourette's syndrome, and a variety of cognitive impairment/neurological syndromes with severe behavioral/emotional symptoms are included among the child neuropsychiatric disorders, the majority of which will lead to ongoing social and academic problems in adult life. Substantial numbers of those affected commit crimes in early adult life, and the incidence of the above-mentioned disorders is higher among young criminal offenders. Early diagnosis, educational, psychological, and, occasionally, medical therapies can affect outcome in a positive way. Child neuropsychiatric disorders should therefore be recognized at an early age so that attitudes can be changed from rejection to understanding, and a gloomy psychosocial outcome avoided.

Adolescent↗

Autism unravelled conference--'the biology of autism--unravelled'.

Autism is a heterogeneous condition, currently with no single explanation for all of these findings presented at this conference. What conferences like this offer us, however, are possible courses of new research and the subsequent development of intervention strategies, both orthodox (pharmacological) and perhaps slightly unorthodox. Aside from the social and emotional issues for both the person with autism and their family, it has been estimated that the cost to the UK for lifetime care of one person with autism is approximately pounds sterling 3 million. With the possibility of an epidemic of autism, is it not time to begin looking at the biomedical factors behind autism spectrum disorders more closely?

Adult↗

Mercury exposure and child development outcomes.

Mercury is ubiquitous in the global environment, ensuring universal exposure. Some forms of mercury are especially neurotoxic, including clinical signs at high doses. However, typical human exposures occur at low to moderate doses. Only limited data about neurotoxicity at low doses are available, and scientists differ in their interpretation. Dose-response data on neurodevelopment are particularly limited. Despite or perhaps because of the lack of sufficient or consistent scientific data, public concern about a link between mercury exposure and developmental disabilities has been rising. After reviewing the data, the US Environmental Protection Agency proposed a reference dose (an estimate of a daily dose that is likely to be without a risk of adverse effects over a lifetime) for methyl mercury that is substantially lower than previous guidelines from the World Health Organization, the US Agency for Toxic Substances and Disease Registry, and the US Food and Drug Administration. Some questions have been raised about the Environmental Protection Agency's guidelines, but the issue remains unresolved. Meanwhile, consumer groups have raised questions about the potential link between mercury exposure and autism spectrum disorders as well as other adverse neurodevelopmental outcomes. This hypothesis has prompted some parents to seek regulatory, legal, or medical remedies in the absence of firm evidence. This article reviews what is known about mercury neurotoxicity and neurodevelopmental risk. Our intent is to focus the debate about mercury on 1) additional research that should be sought and 2) defining the principal issues that public policy makers face.

Child↗

[A cross-sectional study on prevalance and risk factors of disabilities in aged 0-6 years children in Beijing, China].

OBJECTIVE: To explore the epidemiological status of disabilities on vision impairment (VI), hearing loss (HL), mental retardation (MR), autism spectrum disorder (ASD) and motor disorder (MD) in aged 0-6 years old children in Beijing. METHODS: A total of 28 738 children under 7 years old were recruited from permanent residents of Beijing City by 2-phase cluster sampling. The screening procedure was 2-phase, and the diagnosis criteria were developed by the experts group. RESULTS: The overall disability rate was 11.45 per thousand (95 % CI:10.22-12.68). The false negative rates in HL and ASD were 0.14 per thousand, 0.80 per thousand, respectively, with a adjusted overall rate of 12.19per thousand. The prevalence rates of different kind disabilities from high to low were MR 9.31per thousand, MD 2.12per thousand, ASD 1.53per thousand (0.73per thousand before adjusted), HL 1.04per thousand (0.91per thousand before adjusted) VI 0.73per thousand. The results of logistic regression analysis showed that the possible non-biological risk factors for those disabilities were being male, living in city area, advancing age, mother with low education, mother engaged in labor work, and family with low income. It was primarily (49.62%) those prenatal factors other them the known suspected factors that causing disabilities. CONCLUSIONS: Compared with data from a countrywide study in 1987, the overall disability rate had a mild decrease (16.36%) with the most (56.85%) appeared in HL. It is indispensable to establish a disabilities surveillance program for the early recognition and intervention of children with disabilities. It is also crucial to clarify a disability definition for children combined with their characteristics of growth and development. We strongly recommended in developing a new definition on children' disabilities and establishing new criteria according to the contents of developmental disabilities of Center for Disease Control, USA.

Age Distribution↗

Prevalence of four developmental disabilities among children aged 8 years--Metropolitan Atlanta Developmental Disabilities Surveillance Program, 1996 and 2000.

PROBLEM/CONDITION: In the United States, developmental disabilities affect approximately 17% of children aged <18 years, resulting in substantial financial and social costs. REPORTING PERIOD: 1996 and 2000. DESCRIPTION OF SYSTEM: The Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP) monitors the occurrence of mental retardation, cerebral palsy, hearing loss, vision impairment, and autism spectrum disorders among children aged 8 years in the five-county metropolitan Atlanta area (Clayton, Cobb, DeKalb, Fulton, and Gwinnett). MADDSP uses a multiple source ascertainment methodology. RESULTS: During 1996, the prevalence of mental retardation was 15.5 per 1,000 children aged 8 years; it decreased to 12.0 per 1,000 in 2000. The overall prevalence of cerebral palsy was 3.6 per 1,000 in 1996 and 3.1 per 1,000 in 2000. The prevalence of mental retardation and cerebral palsy was highest among males and black children. The prevalence of hearing loss was 1.4 per 1,000 in 1996 and 1.2 per 1,000 in 2000; the prevalence of vision impairment during 1996 was 1.4 per 1,000 and 1.2 per 1,000 in 2000. Minimal differences by study year were observed in the prevalence of all four disabilities when examined by sex, race, and severity. INTERPRETATION: The prevalence of these four select developmental disabilities in MADDSP was higher in 1996 than the annual average prevalence estimates for these disabilities during previous MADDSP study years (1991-1994) study years; the highest increase was observed among children with mental retardation. However, prevalence estimates during 2000 were more consistent with the estimates from the early 1990s. Data from additional surveillance years (2002 and beyond) are needed to determine if the prevalence for 1996 was an anomaly and to continue to monitor trends in the prevalence of developmental disabilities over time. PUBLIC HEALTH ACTIONS: MADDSP data will continue to be used to examine trends in the occurrence of these disabilities over time, facilitate the development and implementation of appropriate intervention programs, and provide a framework for conducting population-based etiologic studies.

Autistic Disorder↗