Pubmed du 01/01/22
1. Çalışkan E, Şahin MN, Güldağ MA. Oxytocin and Oxytocin Receptor Gene Regulation in Williams Syndrome: A Systematic Review. The Yale journal of biology and medicine. 2021; 94(4): 623-35.
Williams Syndrome (WS) is a rare genetic multisystem disorder that occurs because of a deletion of approximately 25 genes in the 7q11.23 chromosome region. This causes dysmorphic facial appearances, multiple congenital cardiovascular defects, delayed motor skills, and abnormalities in connective tissues and the endocrine system. The patients are mostly diagnosed with mild to moderate mental retardation, however, they have a hyper sociable, socially dis-inhibited, and outgoing personality, empathetic behavior, and are highly talkative. Oxytocin (OT), a neuropeptide synthesized at the hypothalamus, plays an important role in cognition and behavior, and is thought to be affecting WS patients’ attitudes at its different amounts. Oxytocin receptor gene (OXTR), on chromosome 3p25.3, is considered regulating oxytocin receptors, via which OT exerts its effect. WS is a crucial disorder to understand gene, hormone, brain, and behavior associations in terms of sociality and neuropsychiatric conditions. Alterations to the WS gene region offer an opportunity to deepen our understandings of autism spectrum disorder, schizophrenia, anxiety, or depression. We aim to systematically present the data available of OT/OXTR regulation and expression, and the evidence for whether these mechanisms are dysregulated in WS. These results are important, as they predict strong epigenetic control over social behavior by methylation, single nucleotide polymorphisms, and other alterations. The comparison and collaboration of these studies may help to establish a better treatment or management approach for patients with WS if backed up with future research.
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2. Nagai Y, Mizutani Y, Nomura K, Uemura O, Saitoh S, Iwata O. Diagnostic rate of autism spectrum disorder in a high-survival cohort of children born very preterm: A cross-sectional study. International journal of developmental neuroscience : the official journal of the International Society for Developmental Neuroscience. 2022; 82(2): 188-95.
To investigate the diagnostic rate of autism spectrum disorder (ASD) in a high-survival cohort of very preterm children, 77 infants born very preterm (<32 weeks of gestation) were assessed at age 4-6 years old using the Autism Diagnostic Observation Schedule, 2nd edition (ADOS-2) and the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). Sixteen children (20.8%) were classified as both DSM-5-positive ASD and ADOS-2-identified "autism," which were defined as confirmed ASD in this study. Our result suggests that the prevalence of ASD in very preterm children might be much higher than reported in previous studies when all children were individually evaluated. Further studies in a large sample are required to clarify the true risk of ASD in preterm birth.
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3. Protic D, Salcedo-Arellano MJ, Stojkovic M, Saldarriaga W, Ávila Vidal LA, Miller RM, Tabatadze N, Peric M, Hagerman R, Budimirovic DB. Raising Knowledge and Awareness of Fragile X Syndrome in Serbia, Georgia, and Colombia: A Model for Other Developing Countries?. The Yale journal of biology and medicine. 2021; 94(4): 559-71.
Fragile X syndrome is the most common monogenetic cause of inherited intellectual disability and syndromic autism spectrum disorder. Fragile X syndrome is caused by an expansion (full mutation ≥200 CGGs repeats, normal 10-45 CGGs) of the fragile X mental retardation 1 (FMR1) gene, epigenetic silencing of the gene, which leads to reduction or lack of the gene’s product: the fragile X mental retardation protein. In this cross-sectional study, we assessed general and pharmacotherapy knowledge (GK and PTK) of fragile X syndrome and satisfaction with education in neurodevelopmental disorders (NDDs) among senior medical students in Serbia (N=348), Georgia (N=112), and Colombia (N=58). A self-administered 18-item questionnaire included GK (8/18) and PTK (7/18) components and self-assessment of the participants education in NDDs (3/18). Roughly 1 in 5 respondents had correct answers on half or more facts about fragile X syndrome (GK>PTK), which ranged similarly 5-7 in Serbia, 6-8 in Georgia, and 5-8 in Colombia, respectively. No cohort had an average value greater than 9 (60%) that would represent passing score « cut-off. » None of the participants answered all the questions correctly. More than two-thirds of the participants concluded that they gained inadequate knowledge of NDDs during their studies, and that their education in this field should be more intense. In conclusion, there is a major gap in knowledge regarding fragile X syndrome among senior medical students in these three developing countries. The finding could at least in part be generalized to other developing countries aimed toward increasing knowledge and awareness of NDDs and fostering an institutional collaboration between developed and developing countries.
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4. Soma D, Hirosawa T, Hasegawa C, An KM, Kameya M, Hino S, Yoshimura Y, Nobukawa S, Iwasaki S, Tanaka S, Yaoi K, Sano M, Shiota Y, Naito N, Kikuchi M. Atypical Resting State Functional Neural Network in Children With Autism Spectrum Disorder: Graph Theory Approach. Frontiers in psychiatry. 2021; 12: 790234.
Measuring whole brain networks is a promising approach to extract features of autism spectrum disorder (ASD), a brain disorder of widespread regions. Objectives of this study were to evaluate properties of resting-state functional brain networks in children with and without ASD and to evaluate their relation with social impairment severity. Magnetoencephalographic (MEG) data were recorded for 21 children with ASD (7 girls, 60-89 months old) and for 25 typically developing (TD) control children (10 girls, 60-91 months old) in a resting state while gazing at a fixation cross. After signal sources were localized onto the Desikan-Killiany brain atlas, statistical relations between localized activities were found and evaluated in terms of the phase lag index. After brain networks were constructed and after matching with intelligence using a coarsened exact matching algorithm, ASD and TD graph theoretical measures were compared. We measured autism symptoms severity using the Social Responsiveness Scale and investigated its relation with altered small-worldness using linear regression models. Children with ASD were found to have significantly lower small-worldness in the beta band (p = 0.007) than TD children had. Lower small-worldness in the beta band of children with ASD was associated with higher Social Responsiveness Scale total t-scores (p = 0.047). Significant relations were also inferred for the Social Awareness (p = 0.008) and Social Cognition (p = 0.015) sub-scales. Results obtained using graph theory demonstrate a difference between children with and without ASD in MEG-derived resting-state functional brain networks, and the relation of that difference with social impairment. Combining graph theory and MEG might be a promising approach to establish a biological marker for ASD.
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5. St John LJ, Rao N. Autism spectrum disorder in a child with megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP). BMJ case reports. 2021; 14(12).
Megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP) is a rare disorder that arises as a result of a somatic mosaic mutation in the PIK3CA gene. It characteristically presents with postnatal or congenital megalencephaly, cutaneous capillary malformations, postaxial polydactyly and often segmental or focal body overgrowth. We report a 7-year-old boy with known MCAP who was diagnosed at around 10 months old with a mosaic change in the PIK3CA gene. He was found to have hall-mark clinical signs; macrocephaly and four-limb postaxial polydactyly. Since diagnosis, he has had multiple clinical features, most of which typically present in children with MCAP. He has now been diagnosed with autism spectrum disorder (ASD), demand avoidance and is under assessment for attention deficit hyperactivity disorder. Although some cases have been raised to the M-CM Network, to our knowledge this is the first case of ASD in MCAP to be reported in the literature.
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6. Usui N, Tian X, Harigai W, Togawa S, Utsunomiya R, Doi T, Miyoshi K, Shinoda K, Tanaka J, Shimada S, Katayama T, Yoshimura T. Length impairments of the axon initial segment in rodent models of attention-deficit hyperactivity disorder and autism spectrum disorder. Neurochemistry international. 2022; 153: 105273.
The axon initial segment (AIS) is a structural neuronal compartment of the proximal axon that plays key roles in sodium channel clustering, action potential initiation, and signal propagation of neuronal outputs. Mutations in constitutive genes of the AIS, such as ANK3, have been identified in patients with neurodevelopmental disorders. Nevertheless, morphological changes in the AIS in neurodevelopmental disorders have not been characterized. In this study, we investigated the length of the AIS in rodent models of attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). We observed abnormalities in AIS length in both animal models. In ADHD model rodents, we observed shorter AIS length in layer 2/3 (L2/3) neurons of the medial prefrontal cortex (mPFC) and primary somatosensory barrel field (S1BF). Further, we observed shorter AIS length in S1BF L5 neurons. In ASD model mice, we observed shorter AIS length in L2/3 and L5 neurons of the S1BF. These results suggest that impairments in AIS length are common phenomena in neurodevelopmental disorders such as ADHD and ASD and may be conserved across species. Our findings provide novel insight into the potential contribution of the AIS to the pathophysiology and pathogenesis of neurodevelopmental disorders.
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7. Volk HE, Ames JL, Chen A, Fallin MD, Hertz-Picciotto I, Halladay A, Hirtz D, Lavin A, Ritz B, Zoeller T, Swanson M. Considering Toxic Chemicals in the Etiology of Autism. Pediatrics. 2022; 149(1).
