Inhibition of G-protein signalling in cardiac dysfunction of intellectual developmental disorder with cardiac arrhythmia (IDDCA) syndrome

BACKGROUND

Pathogenic variants of GNB5 encoding the β5 subunit of the guanine nucleotide-binding protein cause IDDCA syndrome, an autosomal recessive neurodevelopmental disorder associated with cognitive disability and cardiac arrhythmia, particularly severe bradycardia.

METHODS

We used echocardiography and telemetric ECG recordings to investigate consequences of Gnb5 loss in mouse.

RESULTS

We delineated a key role of Gnb5 in heart sinus conduction and showed that Gnb5-inhibitory signalling is essential for parasympathetic control of heart rate (HR) and maintenance of the sympathovagal balance. Gnb5-/- mice were smaller and had a smaller heart than Gnb5+/+ and Gnb5+/- , but exhibited better cardiac function. Lower autonomic nervous system modulation through diminished parasympathetic control and greater sympathetic regulation resulted in a higher baseline HR in Gnb5-/- mice. In contrast, Gnb5-/- mice exhibited profound bradycardia on treatment with carbachol, while sympathetic modulation of the cardiac stimulation was not altered. Concordantly, transcriptome study pinpointed altered expression of genes involved in cardiac muscle contractility in atria and ventricles of knocked-out mice. Homozygous Gnb5 loss resulted in significantly higher frequencies of sinus arrhythmias. Moreover, we described 13 affected individuals, increasing the IDDCA cohort to 44 patients.

CONCLUSIONS

Our data demonstrate that loss of negative regulation of the inhibitory G-protein signalling causes HR perturbations in Gnb5-/- mice, an effect mainly driven by impaired parasympathetic activity. We anticipate that unravelling the mechanism of Gnb5 signalling in the autonomic control of the heart will pave the way for future drug screening.

Expanding the phenotype of ASXL3-related syndrome: A comprehensive description of 45 unpublished individuals with inherited and de novo pathogenic variants in ASXL3

The study aimed at widening the clinical and genetic spectrum of ASXL3-related syndrome, a neurodevelopmental disorder, caused by truncating variants in the ASXL3 gene. In this international collaborative study, we have undertaken a detailed clinical and molecular analysis of 45 previously unpublished individuals with ASXL3-related syndrome, as well as a review of all previously published individuals. We have reviewed the rather limited functional characterization of pathogenic variants in ASXL3 and discuss current understanding of the consequences of the different ASXL3 variants. In this comprehensive analysis of ASXL3-related syndrome, we define its natural history and clinical evolution occurring with age. We report familial ASXL3 pathogenic variants, characterize the phenotype in mildly affected individuals and discuss nonpenetrance. We also discuss the role of missense variants in ASXL3. We delineate a variable but consistent phenotype. The most characteristic features are neurodevelopmental delay with consistently limited speech, significant neuro-behavioral issues, hypotonia, and feeding difficulties. Distinctive features include downslanting palpebral fissures, hypertelorism, tubular nose with a prominent nasal bridge, and low-hanging columella. The presented data will inform clinical management of individuals with ASXL3-related syndrome and improve interpretation of new ASXL3 sequence variants.

Abnormal Right-Hemispheric Sulcal Patterns Correlate with Executive Function in Adolescents with Tetralogy of Fallot

Neurodevelopmental disabilities are the most common noncardiac conditions in patients with congenital heart disease (CHD). Executive function skills have been frequently observed to be decreased among children and adults with CHD compared with peers, but a neuroanatomical basis for the association is yet to be identified. In this study, we quantified sulcal pattern features from brain magnetic resonance imaging data obtained during adolescence among 41 participants with tetralogy of Fallot (ToF) and 49 control participants using a graph-based pattern analysis technique. Among patients with ToF, right-hemispheric sulcal pattern similarity to the control group was decreased (0.7514 vs. 0.7553, P = 0.01) and positively correlated with neuropsychological testing values including executive function (r = 0.48, P < 0.001). Together these findings suggest that sulcal pattern analysis may be a useful marker of neurodevelopmental risk in patients with CHD. Further studies may elucidate the mechanisms leading to different alterations in sulcal patterning.

Timing of Pubertal Onset in Girls and Boys With Constitutional Delay

CONTEXT

The decision whether to treat a child with delayed puberty with sex steroids is primarily based on patient, family, and provider preference. Knowing when children with constitutional delay eventually enter puberty would inform this decision.

OBJECTIVE, DESIGN, SETTING, PARTICIPANTS, AND OUTCOME MEASURES

To estimate and compare rates of pubertal entry, we conducted a retrospective cohort study by reviewing medical records of children evaluated for delayed puberty at a large academic medical center between 2000 and 2015, extracting data on pubertal status for all clinical visits, then conducting time-to-event analyses.

RESULTS

Of 392 girls and 683 boys with delayed puberty, constitutional delay was the most common cause, found in 32% of girls and 70% of boys. In a subcohort of 97 girls and 243 boys who were prepubertal at one or more visits, we observed a broad age range for pubertal entry, up to >16 years for girls and >17 years for boys. The probability of entering puberty within the next year for 12- to 15.5-year-old girls and 13.5- to 16.5-year-old boys with delayed puberty ranged between 38% and 74%. No differences in the rates of pubertal entry were seen between girls and boys after data harmonization.

CONCLUSION

The broad range of ages at pubertal entry for children with constitutional delay challenges the concept that constitutional delay is merely an extreme of normal variation. Discussions with patients and families about management should consider the possibility that some children may need to wait years after presentation until puberty starts.

Mitochondrial Proteostasis Requires Genes Encoded in a Neurodevelopmental Syndrome Locus

Eukaryotic cells maintain proteostasis through mechanisms that require cytoplasmic and mitochondrial translation. Genetic defects affecting cytoplasmic translation perturb synapse development, neurotransmission, and are causative of neurodevelopmental disorders, such as Fragile X syndrome. In contrast, there is little indication that mitochondrial proteostasis, either in the form of mitochondrial protein translation and/or degradation, is required for synapse development and function. Here we focus on two genes deleted in a recurrent copy number variation causing neurodevelopmental disorders, the 22q11.2 microdeletion syndrome. We demonstrate that SLC25A1 and MRPL40, two genes present in the microdeleted segment and whose products localize to mitochondria, interact and are necessary for mitochondrial ribosomal integrity and proteostasis. Our Drosophila studies show that mitochondrial ribosome function is necessary for synapse neurodevelopment, function, and behavior. We propose that mitochondrial proteostasis perturbations, either by genetic or environmental factors, are a pathogenic mechanism for neurodevelopmental disorders.SIGNIFICANCE STATEMENT The balance between cytoplasmic protein synthesis and degradation, or cytoplasmic proteostasis, is required for normal synapse function and neurodevelopment. Cytoplasmic and mitochondrial ribosomes are necessary for two compartmentalized, yet interdependent, forms of proteostasis. Proteostasis dependent on cytoplasmic ribosomes is a well-established target of genetic defects that cause neurodevelopmental disorders, such as autism. Here we show that the mitochondrial ribosome is a neurodevelopmentally regulated organelle whose function is required for synapse development and function. We propose that defective mitochondrial proteostasis is a mechanism with the potential to contribute to neurodevelopmental disease.

Gestational Age at Birth and Risk of Developmental Delay: The Upstate KIDS Study

OBJECTIVE

The aim of this study is to model the association between gestational age at birth and early child development through 3 years of age.

STUDY DESIGN

Development of 5,868 children in Upstate KIDS (New York State; 2008-2014) was assessed at 7 time points using the Ages and Stages Questionnaire (ASQ). The ASQ was implemented using gestational age corrected dates of birth at 4, 8, 12, 18, 24, 30, and 36 months. Whether children were eligible for developmental services from the Early Intervention Program was determined through linkage. Gestational age was based on vital records. Statistical models adjusted for covariates including sociodemographic factors, maternal smoking, and plurality.

RESULTS

Compared with gestational age of 39 weeks, adjusted odds ratios (aOR) and 95% confidence intervals of failing the ASQ for children delivered at <32, 32-34, 35-36, 37, 38, and 40 weeks of gestational age were 5.32 (3.42-8.28), 2.43 (1.60-3.69), 1.38 (1.00-1.90), 1.37 (0.98-1.90), 1.29 (0.99-1.67), 0.73 (0.55-0.96), and 0.51 (0.32-0.82). Similar risks of being eligible for Early Intervention Program services were observed (aOR: 4.19, 2.10, 1.29, 1.20, 1.01, 1.00 [ref], 0.92, and 0.78 respectively for <32, 32-34, 37, 38, 39 [ref], 40, and 41 weeks).

CONCLUSION

Gestational age was inversely associated with developmental delays for all gestational ages. Evidence from our study is potentially informative for low-risk deliveries at 39 weeks, but it is notable that deliveries at 40 weeks exhibited further lower risk.

Early access to physiotherapy for infants with cerebral palsy: A retrospective chart review

AIM

This study aimed to investigate whether children with cerebral palsy (CP) had equal access to timely physiotherapy. Additionally, to learn more about clinical characteristics of infants with CP, we explored differences in neonatal clinical history and CP profile between children referred by a neonatologist or enrolled in neonatal follow-up and those referred by other healthcare professionals as well as those referred before and after 5 months corrected age.

METHODS

We conducted a retrospective chart review study including children born in Uppsala County, Sweden, from 2010 to 2016, who had received a CP diagnosis by July 2019. Entries by doctors and physiotherapists working at Uppsala University Children's Hospital were reviewed.

RESULTS

Thirty-eight children were included (21 girls, 55.3%) in the study. Twenty-two (57.9%) were born at term. Twenty-five children (66%) had their first visit to a physiotherapist before 5 months corrected age, and this included all children (n = 22, 57.9%) referred by a neonatologist or enrolled in neonatal follow-up. The latter group had significantly earlier access to physiotherapy compared to children referred by other healthcare professionals, with a median of 1.9 (min-max: -1-4) and 7.6 (min-max: 1-24) months, respectively (p < 0.0001). Referral source explained unique variance in predicting time of referral to physiotherapist (R2 0.550, B 4.213, p < 0.0001) when controlling for both number of risk factors and severity of motor impairment. However, number of risk factor was vital for early access to physiotherapy for children referred by other health care professionals. Children referred by a neonatologist or enrolled in neonatal follow-up or referred before 5 months corrected age differed on all measured variables concerning neonatal clinical history and CP profile, compared to children referred by other healthcare professionals or after 5 months corrected age. The latter groups had milder forms of CP. In total, twenty-eight children (73.7%) were ambulatory at 2 years of age. Bilateral spastic CP was most common among those referred by a neonatologist or enrolled in neonatal follow-up or referred before 5 months corrected age, while unilateral spastic CP was most common among those referred by other healthcare professionals or after 5 months corrected age.

CONCLUSION

Infants with CP have unequal access to timely physiotherapy, and children considered at low risk for CP receive therapy later. Neonatal follow-up of infants considered at high risk for CP that involves an assessment of motor performance using an evidence-based method during the first months of life corrected age seems to be effective in identifying CP early. Conversely, measuring milestone attainment seems to be a less reliable method for early identification. To provide safe and equal care, all professionals performing developmental surveillance should receive proper training and use evidence-based assessment methods. Physiotherapy should be available prior to formal medical diagnosis.

Early Diagnosis and Treatment of an Infant with a Novel Thyroid Hormone Receptor α Gene (pC380SfsX9) Mutation

Resistance to thyroid hormone alpha (RTHα) is caused by mutations in thyroid hormone receptor α (THRA). Little is known about the natural history and treatment of RTHα, and diagnosis before the age of 1 year has not been previously reported. A de novo heterozygous THRA mutation (pC380SfsX9) was identified in a 10-month-old female investigated for developmental delay, hypotonia, macrocephaly, and severe constipation. Treatment with levothyroxine was accompanied by an appropriate rise in thyroxine (T4), triiodothyronine (T3), as well as decrease in thyrotropin levels and in the T3/T4 ratio with a trend toward normalization of peripheral markers of thyroid hormone action. THRA pC380SfsX9 results in extreme RTHα.

Effects of locomotion task constraints on running in boys with overweight/obesity: The mediating role of developmental delays

BACKGROUND

Childhood obesity adversely affects the musculoskeletal system and is accompanied with motor development delays. Movement interventions that change the body composition and movement patterns is suggested as an effective way to minimise the childhood obesity adverse effects.

RESEARCH QUESTION

Whether a locomotion task constraints intervention is effective to change body composition, motor performance and running efficiency in overweight/obese boys with different levels of motor development.

METHODS

Forty young boys (age: 8.21 ± 1.01 years) whose body mass index (BMI) was above the 85th normative ranked score were divided into 4 independent groups according to their development and BMI: intervention-typical, intervention-delay, control-typical and control-delay. A 6-week task constraints intervention with an emphasis on improving locomotion skills such as fast walking, running, jumping, hopping, skipping and leaping were carried out in the intervention group.

RESULTS

The pre and post-intervention difference score on the sample dependent variables showed decreases in body mass and BMI and improvements in agility, joint kinematics and running economy in the intervention-typical group relative to other groups.

SIGNIFICANCE

The findings highlight that the boys with overweight/obesity and typical development can benefit more from a short-term developmentally-appropriate intervention to refine the running pattern and agility skill that was accompanied by positive changes in body composition.

Concurrent validity of the Warner Initial Developmental Evaluation of Adaptive and Functional Skills and the Bayley Scales of Infant and Toddler Development, Third Edition

AIM

To determine the concurrent validity of the Warner Initial Developmental Evaluation of Adaptive and Functional Skills (WIDEA-FS), a criterion-specified questionnaire that assesses a child's adaptive skills in everyday contexts, and the Bayley Infant and Toddler Scales of Development, Third Edition (Bayley-III).

METHOD

In a prospective cohort study, 431 WIDEA-FS and Bayley-III assessments were completed among 341 children, aged 10 to 36 months corrected age (158 females, 183 males; median [interquartile range] gestational age at birth 32wks [29-38]), monitored in a high-risk neonatal intensive care unit follow-up clinic.

RESULTS

WIDEA-FS scores were significantly associated with Bayley-III scores in all domains. Lower scores on the WIDEA-FS were significantly associated with an increased risk of adverse developmental performance on all Bayley-III scales. The association was strongest for motor and language Bayley-III scores when tested at <30 months of age, and for cognitive Bayley-III scores when tested at ≥30 months of age.

INTERPRETATION

The WIDEA-FS has concurrent validity with the Bayley-III and may be a useful tool in high-risk follow-up settings.

WHAT THIS PAPER ADDS

WIDEA-FS mobility, communication, and social cognition domains are concurrently valid in infants at high-risk for neurodevelopmental disability. Bayley-III motor, language, and cognitive composite scores are concurrently valid in the same group. The WIDEA-FS mobility and communication domains may be most clinically useful in children <30 months.

Curcumin Prevents Cerebellar Hypoplasia and Restores the Behavior in Hyperbilirubinemic Gunn Rat by a Pleiotropic Effect on the Molecular Effectors of Brain Damage

Bilirubin toxicity to the central nervous system (CNS) is responsible for severe and permanent neurologic damage, resulting in hearing loss, cognitive, and movement impairment. Timely and effective management of severe neonatal hyperbilirubinemia by phototherapy or exchange transfusion is crucial for avoiding permanent neurological consequences, but these therapies are not always possible, particularly in low-income countries. To explore alternative options, we investigated a pharmaceutical approach focused on protecting the CNS from pigment toxicity, independently from serum bilirubin level. To this goal, we tested the ability of curcumin, a nutraceutical already used with relevant results in animal models as well as in clinics in other diseases, in the Gunn rat, the spontaneous model of neonatal hyperbilirubinemia. Curcumin treatment fully abolished the landmark cerebellar hypoplasia of Gunn rat, restoring the histological features, and reverting the behavioral abnormalities present in the hyperbilirubinemic rat. The protection was mediated by a multi-target action on the main bilirubin-induced pathological mechanism ongoing CNS damage (inflammation, redox imbalance, and glutamate neurotoxicity). If confirmed by independent studies, the result suggests the potential of curcumin as an alternative/complementary approach to bilirubin-induced brain damage in the clinical scenario.

Impact of COVID-19 outbreak on mental health and perceived strain among caregivers tending children with special needs

BACKGROUND

While COVID-19 outbreak has had adverse psychological effects in children with special needs, the mental state and burden on their caregivers during this pandemic has yet to be reported.

AIMS

The objectives of this study were to describe the mental health status and the change in perceived strain among caregivers during the COVID-19 outbreak.

METHODS AND PROCEDURES

Two hundred sixty four caregivers completed an online survey that assessed demographics, use and perspective on tele-rehabilitation, homecare therapy, caregiver's strain and mental health.

OUTCOMES AND RESULTS

The prevalence of depression, anxiety and stress symptoms were found to be 62.5 %, 20.5 % and 36.4 % respectively. A significant difference in caregiver strain (p <  0.001, effect size = 0.93) was observed during the outbreak compared to levels pre-outbreak (pre-outbreak strain was measured retrospectively). Caregivers not using tele-rehabilitation along with a perception of it being a poor medium for rehabilitation were at greater risks for poor mental health whereas a negative perception on homecare therapy were strongly associated with higher psychological symptoms and strain.

CONCLUSIONS AND IMPLICATIONS

This study identified a high prevalence of depression and significant change in strain displayed by caregivers during the COVID-19 outbreak. We identified several factors associated with poor mental health and perceived strain that can be used to help safeguard caregivers.

A multi-task, multi-stage deep transfer learning model for early prediction of neurodevelopment in very preterm infants

Survivors following very premature birth (i.e., ≤ 32 weeks gestational age) remain at high risk for neurodevelopmental impairments. Recent advances in deep learning techniques have made it possible to aid the early diagnosis and prognosis of neurodevelopmental deficits. Deep learning models typically require training on large datasets, and unfortunately, large neuroimaging datasets with clinical outcome annotations are typically limited, especially in neonates. Transfer learning represents an important step to solve the fundamental problem of insufficient training data in deep learning. In this work, we developed a multi-task, multi-stage deep transfer learning framework using the fusion of brain connectome and clinical data for early joint prediction of multiple abnormal neurodevelopmental (cognitive, language and motor) outcomes at 2 years corrected age in very preterm infants. The proposed framework maximizes the value of both available annotated and non-annotated data in model training by performing both supervised and unsupervised learning. We first pre-trained a deep neural network prototype in a supervised fashion using 884 older children and adult subjects, and then re-trained this prototype using 291 neonatal subjects without supervision. Finally, we fine-tuned and validated the pre-trained model using 33 preterm infants. Our proposed model identified very preterm infants at high-risk for cognitive, language, and motor deficits at 2 years corrected age with an area under the receiver operating characteristic curve of 0.86, 0.66 and 0.84, respectively. Employing such a deep learning model, once externally validated, may facilitate risk stratification at term-equivalent age for early identification of long-term neurodevelopmental deficits and targeted early interventions to improve clinical outcomes in very preterm infants.

Comparative analysis of self-injurious behaviour topographies in young children with and without developmental delay

BACKGROUND

The present study presents post hoc analyses of specific topographies of self-injurious behaviour (SIB) exhibited by young children with developmental delay (DD) and children with typical development (TD). We conducted these analyses to better understand similarities and differences between the groups from a developmental perspective. No previous study has compared the prevalence, severity and co-occurrence of specific topographies of SIB in young children.

METHOD

The participants were parents of two groups of children one with DD (n = 49, mean age = 37.5 months) and one with TD (n = 49, mean age = 36.6 months). Individual items of the SIB subscale from the Repetitive Behaviour Scale-Revised were used in the analyses.

RESULTS

Seven of the eight Repetitive Behaviour Scale-Revised SIB categories were reported for both groups. Children in the DD group were significantly more likely to engage in Hits Self against Surface or Object, Hits Self with Body Part, Inserts Finger or Object, Skin Picking and Bites Self. Parental ratings of severity were also significantly greater for the DD group for these five topographies. The DD group engaged in a significantly greater number of SIB topographies than the children in the TD group. Children in the TD group were more likely to exhibit a single SIB topography while the DD group were more likely to engage in two or more topographies. Topographies involving self-hitting were not only more frequent among the children in the DD group but also more likely to be rated as moderate or severe in nature.

CONCLUSIONS

Compared with the TD group, the topographies of SIB exhibited by the DD group were more prevalent, more severe and co-occurred with greater frequency. Inclusion of a group of children with TD provided an important comparative context for the occurrence of SIB in children with DD.

Interobserver Variability for Measurement of Grating Acuity in Preverbal and Nonverbal Children Using Lea Grating Paddles

PURPOSE

To study interobserver variability for measurement of grating acuity in preverbal and nonverbal children with developmental delay using Lea Grating Paddles (Lea Hyvärinen).

METHODS

In this prospective study, preverbal patients younger than 3 years and older nonverbal patients (with developmental delay) were included. Those with poor neck holding were excluded. Binocular and monocular visual acuity assessment was done simultaneously using Lea Grating Paddles by two examiners who were blinded from each other's results.

RESULTS

Thirty-one children were tested (19 [61.29%] males and 12 [38.71%] females). The mean age was 28.5 months (range: 4 to 44 months). A total of 92% of the observations showed interobserver agreement of 0.5 octave or better in binocular testing. Results for monocular testing showed interobserver agreement (0.5 octaves or better) in 95.65% and 95.23% of right and left eyes, respectively. Combined results showed agreement better than 0.5 octaves in 94.20%. The mean binocular visual acuity was 2.07 and 2.14 cycles per degree (cpd) for the first and second observer, respectively (P = .59). Similarly, the mean monocular visual acuity for the right and left eyes was 0.98 and 0.97 cpd for observer 1 and 0.89 and 0.79 cpd for observer 2, respectively (P = .91 and .14, for the right and left eyes, respectively).

CONCLUSIONS

Interobserver variability for grating acuity measurement using Lea Grating Paddles is minimal, signifying it to be a reliable and reproducible alternative to conventional preferential looking testing procedures. [J Pediatr Ophthalmol Strabismus. 2020;57(5):305-308.].

Development of children born from freeze-only versus fresh embryo transfer: follow-up of a randomized controlled trial

OBJECTIVE

To compare the longer-term development outcomes in children born after freeze-only versus fresh embryo transfer (ET) in women with an ovulatory cycle.

DESIGN

Long-term follow-up study (NCT04099784) of babies born alive after the first ET in a randomized controlled trial (RCT) comparing ongoing pregnancy and live birth rates after use of a freeze-only versus fresh ET strategy (NCT02471573).

SETTING

Private clinic.

PATIENT(S)

Of 391 couples randomized to each treatment group in the RCT, 132 (97 singleton/35 twins) and 123 (95 singleton/28 twins) in the freeze-only and fresh ET groups had live birth; 113 parents (86%) from the freeze-only group (147 babies) and 99 (80%) from the fresh ET group (120 babies) returned questionnaires for this follow-up study.

INTERVENTION(S)

Use of a freeze-only or fresh ET strategy after controlled ovarian hyperstimulation with a follicle-stimulating hormone/gonadotropin-releasing antagonist protocol.

MAIN OUTCOME MEASURE(S)

Developmental status at ≥2 years after birth, determined using the Developmental Red Flags and Ages & Stages Third Edition (ASQ-3) Questionnaires.

RESULT(S)

Mean age of children at the end of follow-up was 37 months. Height (95.0 ± 6.1 vs. 95.7 ± 5.6 cm) and weight (14.9 ± 2.6 vs. 14.8 ± 2.6 kg) were similar in the freeze-only and fresh ET groups (results were similar when singletons and twins were analyzed separately). Overall, ASQ-3 scores for problem solving were significantly better in the freeze-only versus fresh ET group (overall: 53.6 ± 8.4 vs. 51.1 ± 10.2), with no significant between-group difference when singletons (52.3 ± 10.1 vs. 51.0 ± 9.9) and twins (55.0 ± 5.5 vs. 51.4 ± 11.1) were analyzed separately. Fine motor skills scores were numerically higher (with P values approaching statistical significance) in the freeze-only versus fresh ET group in the overall analysis (47.8 ± 11.6 vs. 44.9 ± 12.6) and twins (49.85 ± 8.72 vs. 43.93 ± 12.71), but not singletons (46.0 ± 13.4 vs. 45.4 ± 12.6). The overall proportion of children with abnormal ASQ-3 (6.8% vs. 8.3%) or abnormal Red Flags (5.4% vs. 6.7%) findings in the freeze-only and fresh ET groups was low and did not differ significantly between groups.

CONCLUSION(S)

These data provide physicians with additional information on which to base decisions about the relative merits of different approaches to infertility treatment. There do not appear to be any grounds for concern about worse outcomes after use of a freeze-only strategy. However, additional studies comparing childhood development after a freeze-only strategy, fresh ET, and natural cycles are needed before firm conclusions can be drawn.

Homozygous splice-variants in human ARV1 cause GPI-anchor synthesis deficiency

BACKGROUND

Mutations in the ARV1 Homolog, Fatty Acid Homeostasis Modulator (ARV1), have recently been described in association with early infantile epileptic encephalopathy 38. Affected individuals presented with epilepsy, ataxia, profound intellectual disability, visual impairment, and central hypotonia. In S. cerevisiae, Arv1 is thought to be involved in sphingolipid metabolism and glycophosphatidylinositol (GPI)-anchor synthesis. The function of ARV1 in human cells, however, has not been elucidated.

METHODS

Mutations were discovered through whole exome sequencing and alternate splicing was validated on the cDNA level. Expression of the variants was determined by qPCR and Western blot. Expression of GPI-anchored proteins on neutrophils and fibroblasts was analyzed by FACS and immunofluorescence microscopy, respectively.

RESULTS

Here we describe seven patients from two unrelated families with biallelic splice mutations in ARV1. The patients presented with early onset epilepsy, global developmental delays, profound hypotonia, delayed speech development, cortical visual impairment, and severe generalized cerebral and cerebellar atrophy. The splice variants resulted in decreased ARV1 expression and significant decreases in GPI-anchored protein on the membranes of neutrophils and fibroblasts, indicating that the loss of ARV1 results in impaired GPI-anchor synthesis.

CONCLUSION

Loss of GPI-anchored proteins on our patients' cells confirms that the yeast Arv1 function of GPI-anchor synthesis is conserved in humans. Overlap between the phenotypes in our patients and those reported for other GPI-anchor disorders suggests that ARV1-deficiency is a GPI-anchor synthesis disorder.

Predicting individual differences in reading, spelling and maths in a sample of typically developing children: A study in the perspective of comorbidity

We examined reading, spelling, and mathematical skills in an unselected group of 129 Italian fifth graders by testing various cognitive predictors for each behaviour. As dependent variables, we measured performance in behaviours with a clear functional value in everyday life, such as reading a text, spelling under dictation and doing mental and written computations. As predictors, we selected cognitive dimensions having an explicit relation with the target behaviour (called proximal predictors), and prepared various tests in order to select which task had the best predictive power on each behaviour. The aim was to develop a model of proximal predictors of reading (speed and accuracy), spelling (accuracy) and maths (speed and accuracy) characterized by efficacy also in comparison to the prediction based on general cognitive factors (i.e., short-term memory, phonemic verbal fluency, visual perceptual speed, and non-verbal intelligence) and parsimony, pinpointing the role of both common and unique predictors as envisaged in the general perspective of co-morbidity. With one exception (reading accuracy), the proximal predictors models (based on communality analyses) explained a sizeable amount of variance, ranging from 27.5% in the case of calculation (accuracy) to 48.7% of reading (fluency). Models based on general cognitive factors also accounted for some variance (ranging from 6.5% in the case of spelling to 19.5% in the case of reading fluency) but this was appreciably less than that explained by models based on the hypothesized proximal predictors. In general, results confirmed the efficacy of proximal models in predicting reading, spelling and maths although they offered only limited support for common predictors across different learning skills; namely, performance in the Orthographic Decision test entered as a predictor of both reading and spelling indicating that a single orthographic lexicon may account for performance in reading and spelling. Possible lines of research to expand on this approach are illustrated.

A Qualitative Photo Elicitation Research Study to elicit the perception of young children with Developmental Disabilities such as ADHD and/or DCD and/or ASD on their participation

Participation, defined as ‘involvement in life situations’ according to the World Health Organisation, is a well-recognized concept and critical indicator of quality of life. In addition it has become an important outcome measure in child rehabilitation. However, little is known about the level of participation of young children with Developmental Disabilities. The aim of this study was to capture their subjective experiences of participation. An adapted informed consent based on a comic strip was used to get the children’s assent. A Photo Elicitation study was used, in which photographs were taken by the children when they were involved in meaningful activities. The photographs were then used to facilitate communication with the children and to initiate in depth-interviews. Forty-seven interviews with 16 children between five and nine years were conducted based on their photographs. This method generated rich data, confirming that young children with Developmental Disabilities were able to inform us accurately on their experiences of participation. Data was analysed by means of an inductive thematic analysis. Results showed that children perceived their participation as satisfying when they can play, learn and join in family gatherings resulting in feelings of inclusion, recognition and belonging. When there are—on occasions—moments that their participation was obstructed, the children used two strategies to resolve it. Or they walked away from it and choose not to participate, or when autonomously motivated for the activity, they relied primarily on their context (i.e. mothers) as enabling their participation. Related to the data, children discussed themes related to their person, activities, connections and mediators between those themes. These themes fit well within earlier and current research on the subject of participation.

Succinic Semialdehyde Dehydrogenase Deficiency: An Update

Succinic semialdehyde dehydrogenase deficiency (SSADH-D) is a genetic disorder that results from the aberrant metabolism of the neurotransmitter γ-amino butyric acid (GABA). The disease is caused by impaired activity of the mitochondrial enzyme succinic semialdehyde dehydrogenase. SSADH-D manifests as varying degrees of mental retardation, autism, ataxia, and epileptic seizures, but the clinical picture is highly heterogeneous. So far, there is no approved curative therapy for this disease. In this review, we briefly summarize the molecular genetics of SSADH-D, the past and ongoing clinical trials, and the emerging features of the molecular pathogenesis, including redox imbalance and mitochondrial dysfunction. The main aim of this review is to discuss the potential of further therapy approaches that have so far not been tested in SSADH-D, such as pharmacological chaperones, read-through drugs, and gene therapy. Special attention will also be paid to elucidating the role of patient advocacy organizations in facilitating research and in the communication between researchers and patients.

Handwriting Delay in Dyslexia: Children at the End of Primary School Still Make Numerous Short Pauses When Producing Letters

Developmental dyslexia is defined as a specific reading disorder but is also thought to be underpinned by a deficit in motor skills that may well affect handwriting performance. However, the results of studies addressing this issue are not consistent. The present study was, therefore, designed to better understand the functioning of handwriting in children with dyslexia, by conducting an analysis of the legibility and fluency of handwritten letters, supplemented by an assessment of motor skills. The performances of 15 children with dyslexia (M_age = 11.4 years) were compared with those of two groups of typically developing children, one matched for chronological age, the other for orthographic level (M_age = 8.7 years) on two handwriting measures (production of the letters of the alphabet and the child's first name and surname). Results revealed a delay in motor skills, as well as in letter legibility, letter production duration, and the number of short pauses (i.e., lasting between 20 and 199 ms) made during letter production, in the children with dyslexia, with strong negative correlations between motor skills and the number of short pauses. Results are discussed in the context of handwriting control development in children, and perspectives are set out for practitioners.

Deficiencies in vesicular transport mediated by TRAPPC4 are associated with severe syndromic intellectual disability

The conserved transport protein particle (TRAPP) complexes regulate key trafficking events and are required for autophagy. TRAPPC4, like its yeast Trs23 orthologue, is a core component of the TRAPP complexes and one of the essential subunits for guanine nucleotide exchange factor activity for Rab1 GTPase. Pathogenic variants in specific TRAPP subunits are associated with neurological disorders. We undertook exome sequencing in three unrelated families of Caucasian, Turkish and French-Canadian ethnicities with seven affected children that showed features of early-onset seizures, developmental delay, microcephaly, sensorineural deafness, spastic quadriparesis and progressive cortical and cerebellar atrophy in an effort to determine the genetic aetiology underlying neurodevelopmental disorders. All seven affected subjects shared the same identical rare, homozygous, potentially pathogenic variant in a non-canonical, well-conserved splice site within TRAPPC4 (hg19:chr11:g.118890966A>G; TRAPPC4: NM_016146.5; c.454+3A>G). Single nucleotide polymorphism array analysis revealed there was no haplotype shared between the tested Turkish and Caucasian families suggestive of a variant hotspot region rather than a founder effect. In silico analysis predicted the variant to cause aberrant splicing. Consistent with this, experimental evidence showed both a reduction in full-length transcript levels and an increase in levels of a shorter transcript missing exon 3, suggestive of an incompletely penetrant splice defect. TRAPPC4 protein levels were significantly reduced whilst levels of other TRAPP complex subunits remained unaffected. Native polyacrylamide gel electrophoresis and size exclusion chromatography demonstrated a defect in TRAPP complex assembly and/or stability. Intracellular trafficking through the Golgi using the marker protein VSVG-GFP-ts045 demonstrated significantly delayed entry into and exit from the Golgi in fibroblasts derived from one of the affected subjects. Lentiviral expression of wild-type TRAPPC4 in these fibroblasts restored trafficking, suggesting that the trafficking defect was due to reduced TRAPPC4 levels. Consistent with the recent association of the TRAPP complex with autophagy, we found that the fibroblasts had a basal autophagy defect and a delay in autophagic flux, possibly due to unsealed autophagosomes. These results were validated using a yeast trs23 temperature sensitive variant that exhibits constitutive and stress-induced autophagic defects at permissive temperature and a secretory defect at restrictive temperature. In summary we provide strong evidence for pathogenicity of this variant in a member of the core TRAPP subunit, TRAPPC4 that associates with vesicular trafficking and autophagy defects. This is the first report of a TRAPPC4 variant, and our findings add to the growing number of TRAPP-associated neurological disorders.

Communicative Use of Triadic Eye Gaze in Children With Down Syndrome, Autism Spectrum Disorder, and Other Intellectual and Developmental Disabilities

Purpose This study examines differences in the communicative use of triadic eye gaze (TEG) during a communicative interaction in 2 neurodevelopmental disorders: Down syndrome (DS) and autism spectrum disorders (ASD), and a 3rd group of varying disabilities associated with intellectual and developmental disabilities (IDDs). Also, the relationship between TEG use and language abilities was explored. Method Participants were 45 children, 15 in each group. The frequency of TEG was coded during a scripted communication assessment when children were between 3 and 6 years of age (37-73 months). Receptive and expressive language was measured using raw scores from the Mullen Scales of Early Learning concurrently between 3 and 6 years and again 2 years later when children were between 5 and 8 years (59-92 months). Results Descriptively, children with DS had a higher frequency of TEG than children with ASD and IDD, but significant differences were only observed between children with DS and ASD. More TEG at Time 1 in children with DS was associated with higher receptive language at Time 1 and higher expressive language at Time 2. For children with ASD, a trend for a positive association between TEG at Time 1 and language abilities at Time 2 was observed. No significant associations were observed for children with IDD. Conclusion Children with DS used TEG significantly more than children with ASD in this sample. Identifying strengths and weaknesses in TEG use is important because providing caregiver training to facilitate TEG can result in increased opportunities to respond with language models and promote language development.

Changes in temperament over time in young children with autism spectrum disorder and other developmental delays: a follow-up comparison study

BACKGROUND

Although in the last decade some research has emerged on temperament in autism spectrum disorder (ASD), this research has primarily focused on the differences between children with ASD and their typically developing peers rather than the stability or change in temperament in this population. Thus, the goal of this study was to examine temperament over time in children with ASD, developmental delays (DD) and typical development (TD). Temperament differences were also compared among the three groups.

METHODS

To accomplish this, parents rated children's temperament at Time 1 (T1) and Time 2 (T2) using the Carey Temperament Scales (CTS).

RESULTS

Results from the study showed that at T1, parents of children with ASD rated their children as more withdrawn (i.e. approach), and emotionally negative (i.e. mood), and less distractible and adaptable than parents of children with TD and DD. Also, children with ASD were rated as more intense and children with DD as less distractible than their TD peers. Similarly, at T2, children with ASD were rated more withdrawn, and emotionally negative, and less persistent, rhythmic, adaptable and distractible than children with TD and DD. Also, children with ASD were rated as more active than their DD peers. Regarding stability, parent ratings of temperament appeared stable over time in the TD group, but ratings varied substantially in the ASD or DD groups. That is, for the ASD group, activity and approach at T1 were significantly associated with their corresponding dimensions at T2. However, for the TD group, rhythmicity, approach, intensity and mood at T1 were significantly associated with those dimensions at T2. No associations were found in the DD group. Regarding change, parents reported change in rhythmicity, persistence and threshold between T1 and T2 in the ASD group. Similarly, parents reported change in rhythmicity, approach and threshold between T1 and T2 in the DD group. Lastly, parents of TD children reported change in adaptability, persistence and distractibility between T1 and T2.

CONCLUSIONS

These findings are novel in that children with ASD appear to have less stable temperament profile and different change patterns than children with TD or DD. Similar to previous research, children with ASD were described by their parents as experiencing more temperamental difficulties.

The relationship of age, early motor skills and observable child behaviors in young children with developmental delays

BACKGROUND

Children with disabilities often experience delays in one or more domains of development including motor skill delays. Delays in motor skill development may put children further behind their peers without disabilities in respect to aspects of early learning.

AIMS

The purpose of this study was to examine how gross motor skills mediated the relationship of age and the observable child behaviors of compliance and adaptive behavior in a group of young children (2-4 years) with developmental disabilities around one time point.

METHODS

Children with developmental disabilities (N = 113) were assessed on direct measures of motor skills and the child behaviors of compliance and adaptive behavior. Two independent simple mediation analyses were conducted using PROCESS, an ordinary least squares path analysis appropriate for small sample sizes.

RESULTS

Age had a positive relationship with gross motor skills (a = .66, p < .001) when the outcome variable was adaptive behavior and age had a positive relationship with gross motor skills (a = .66, p < .001) when the outcome variable was compliance.

CONCLUSIONS

Motor skill development may promote or hinder development in other childhood behaviors such as compliance and adaptive behavior.

Gait Characteristics of Children Born Preterm

Walking is a central skill of daily living. A delay in the onset of walking can be a sign of abnormal motor development. Further, abnormalities in gait can also affect physical functioning. Children born preterm are at significant risk for neurodevelopmental impairments; however, little is known about how preterm birth affects walking. This review describes current evidence of walking in children born preterm with a focus on the age at onset of walking and comparisons of gait characteristics of children born preterm with those born full-term.

Learning new relational categories by children with autism spectrum disorders, children with typical development and children with intellectual disabilities: effects of comparison and familiarity on systematicity

BACKGROUND

Systematicity principle, used during analogical reasoning, enables building up deeper abstract concepts as part of structure mapping. The purpose of this study was to investigate structure mapping processes that occur during acquisition of new relational categories and to identify the learning patterns and systematicity of children with autism spectrum disorder (ASD) compared with intellectual and developmental disabilities (IDD) and typical development (TD). Comparison effect and level of familiarity were used to investigate structural mapping processes.

METHODS

Three groups of 24 children participated in the study. Using a computer program, participants were asked to select a perceptual or relational choice based on one or two standards using illustrations depicting new relational categories in various spatial configurations. Known, partially known and unknown illustrations were used in depicting three levels of familiarity.

RESULTS

All three groups selected perceptual choices when one standard was available (no comparison). However, when two standards were available, enabling a comparison, children with IDD and TD increased their tendency for selecting abstract relational categories, while children with ASD did not change their preference and continued selecting perceptual choices. Level of familiarity increased selection of relational choices among children with TD and IDD but not among children with ASD.

CONCLUSIONS

Systematicity principle was evident mostly in the selection of relational choices by children with TD and IDD when the illustrations were known or partially known. Hence, even when an opportunity to compare and to use previously known information was available, structure mapping processes and systematicity were implemented to align information among children TD and IDD but failed to assist the learning of new relational categories among children with ASD.

Exploring the cognitive phenotype of Kabuki (Niikawa-Kuroki) syndrome

BACKGROUND

Kabuki syndrome (KS) is a Mendelian disorder, characterised by short stature, facial dysmorphisms and developmental delay and/or intellectual disability. Clarification of the neurocognitive profile in KS may provide directions for education and treatment interventions for KS. Previous studies on cognitive functioning in KS are scarce and have mainly focused on the general level of intelligence. The few more extensive studies suggested weaknesses in language skills, visuoconstruction, perceptual reasoning and speed of information processing. Other relevant domains such as memory, executive functioning and social cognition have not been studied yet.

METHOD

This is the first study in which cognitive functioning within multiple domains is systematically explored in 29 participants with KS (age range: 5-48 years) and compared to both norm groups (healthy population) and an appropriate control group of 15 individuals with other genetic syndromes (age range: 6-28 years).

RESULTS

Compared to the norm groups of the cognitive test manuals, as expected, participants with KS show a weaker performance on all cognitive tests. Comparison with the more appropriate genetic control group indicates weaknesses in visuoconstruction and visual memory and no weaknesses in planning, cognitive flexibility or social cognition. Verbal memory seems to be a relative strength.

CONCLUSIONS

Individuals with KS suffer from specific weaknesses in visuoconstruction, in addition to their intellectual disability/developmental delay. These impairments in visuoconstruction plausibly result from problems in visual perceptual processing, which highlight the importance of the use of auditory cues instead of visual cues in targeted educational support and psychosocial interventions.

Mental health and behavioural problems in children with XXYY: a comparison with intellectual disabilities

BACKGROUND

The phenotype of children with XXYY has predominantly been defined by comparison to other sex chromosome aneuploidies trisomies affecting male children; however, the intellectual ability of children with XXYY is lower than children with other sex chromosome aneuploidies trisomies. It is not known to what extent the phenotype identified to date is specific to XXYY, rather than a reflection of lower IQ. This study evaluates the mental health and behaviour of children with XXYY, in comparison to children with intellectual disabilities of heterogeneous genetic origin.

METHODS

Fifteen children with XXYY and 30 controls matched for age (4-14 years), sex and intellectual ability were ascertained from the IMAGINE ID study. IMAGINE ID participants have intellectual disabilities due to genetic anomalies confirmed by National Health Service Regional Genetic Centre laboratories. The mental health and behaviour of participants was examined with the Development and Well-being Assessment and the Strengths and Difficulties Questionnaire.

RESULTS

Children with XXYY experienced significantly more frequent and intense temper outbursts than the control group.

CONCLUSION

Our results suggest that temper outbursts may be specifically associated with the XXYY phenotype. These problems have a significant impact on the daily lives of boys with XXYY and their families. It is crucial to ensure that families are well supported to manage these difficulties.

Catch-up growth and behavioral development among preterm, small-for-gestational-age children: A nationwide Japanese population-based study

OBJECTIVE

To examine the relationship between the catch-up growth of preterm, SGA children and their behavioral development.

METHODS

We analyzed data from a large Japanese, nationwide, population-based, longitudinal survey that started in 2001. We restricted the study participants to preterm children with information on height at 2 years of age (n = 1667). Catch-up growth for SGA infants was defined as achieving a height at 2 years of age above -2.0 standard deviations for chronological age. We then used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations of SGA/catch-up status with neurobehavioral development both at 5.5 and 8 years of age, adjusting for potential infant- and parent-related confounding factors.

RESULTS

Twenty-six percent of preterm SGA infants failed to catch up. SGA children without catch-up growth were more likely to be unable to listen without fidgeting (OR 2.51, 95% CI: 1.06-5.93) and unable to focus on one task (OR 2.66, 95% CI: 1.09-6.48) compared with non-SGA children at 5.5 years of age. Furthermore, SGA children without catch-up growth were at significant risk for inattention at 8 years of age.

CONCLUSIONS

SGA infants with poor postnatal growth were at risk for attention problems throughout preschool-age to school-age among preterm infants. Early detection and intervention for attention problems among these infants is warranted.

How is your mind-set? Proof of concept for the measurement of the level of emotional development

Background

In persons with intellectual and developmental disabilities, not only cognitive brain functions, but also socio-emotional processing networks may be impaired. This study aims to validate the Scale of Emotional Development—Short (SED-S) to provide an instrument for the assessment of socio-emotional brain functions.

Method

The SED-S was applied in 160 children aged 0–12 years. Criterion validity was investigated at item and scale level in terms of the agreement between the scale classification and the child’s chronological age. Additionally, interrater reliability and internal consistency were assessed.

Results

For the majority of items, the expected response pattern emerged, showing the highest response probabilities in the respective target age groups. Agreement between the classification of the different SED-S domains and chronological age was high (κ_{w =} 0.95; exact agreement = 80.6%). Interrater reliability at domain level ranged from κ_w = .98 to 1.00 and internal consistency was high (α = .99).

Conclusion

The study normed the SED-S in a sample of typically developing children and provides evidence for criterion validity on item, domain and scale level.

The profile of very preterm children on academic achievement. A cross-population comparison with children with specific learning disorders

BACKGROUND

Very preterm (VPT) children showed delays in reading, spelling and maths, but their academic achievement profile is not clearly understood.

AIMS

VPT children were compared with children with specific learning disorders (SLD) and typically developing (TD) children on academic achievement, considering cognitive and linguistic phenotypic markers. A learning profile analysis was also performed.

METHODS

We included 170 10-year old monolingual Italian-speaking children (37 VPT, 28 SLD, 105 TD) assessing cognitive, linguistic and academic skills.

RESULTS

On academic achievements VPT children fell behind TD peers in some reading (text speed, comprehension), spelling (non-word), and math (number knowledge, written calculations and problem-solving) tasks. SLD children underperformed in all academic tasks with respect to VPT and TD peers. Concerning cognitive and linguistic phenotypic markers, compared to TD peers, VPT children showed lower scores in verbal IQ and phonological fluency, SLD children in phonological processing and rapid automatized naming. VPT children showed a higher rate of at-risk performance in reading compared to TD group, but a minor percentage of impaired profiles and comorbidity among learning areas compared to SLD group.

CONCLUSIONS AND IMPLICATIONS

The academic achievement profile of VPT children shows persistent delays, but it differs to that of SLD children, since delays are less widespread and severe, and differences were found in phenotypic markers and comorbidity. Follow-up programs and effective interventions are needed for VPT children.

KAT6A Syndrome: genotype-phenotype correlation in 76 patients with pathogenic KAT6A variants

PURPOSE

Pathogenic variants in KAT6A have recently been identified as a cause of syndromic developmental delay. Within 2 years, the number of patients identified with pathogenic KAT6A variants has rapidly expanded and the full extent and variability of the clinical phenotype has not been reported.

METHODS

We obtained data for patients with KAT6A pathogenic variants through three sources: treating clinicians, an online family survey distributed through social media, and a literature review.

RESULTS

We identified 52 unreported cases, bringing the total number of published cases to 76. Our results expand the genotypic spectrum of pathogenic variants to include missense and splicing mutations. We functionally validated a pathogenic splice-site variant and identified a likely hotspot location for de novo missense variants. The majority of clinical features in KAT6A syndrome have highly variable penetrance. For core features such as intellectual disability, speech delay, microcephaly, cardiac anomalies, and gastrointestinal complications, genotype- phenotype correlations show that late-truncating pathogenic variants (exons 16-17) are significantly more prevalent. We highlight novel associations, including an increased risk of gastrointestinal obstruction.

CONCLUSION

Our data expand the genotypic and phenotypic spectrum for individuals with genetic pathogenic variants in KAT6A and we outline appropriate clinical management.

A schedule of gross motor development for children with Down syndrome

BACKGROUND

Gross motor milestones for children who develop typically have been well established; however, norms for children with Down syndrome (DS) are uncertain. Without a developmental schedule for the gross motor development of children with DS, medical professionals are limited in their ability to identify if the development of a particular child with DS is delayed in comparison with his or her peers (i.e. other children with DS), assess when intervention is needed and answer the questions of parents regarding when their child can be expected to achieve developmental milestones. The objectives of this study are to: (1) provide health care professionals and early intervention providers with longitudinal data on the gross motor development of children with DS gathered prospectively; (2) contribute to the development of a definitive schedule of gross motor development for children with DS; (3) enable the identification of gross motor development that is delayed in comparison with other children with DS; and (4) help medical professionals address the questions of concerned parents who are anxious to know when their child will achieve gross motor skills such as sitting, crawling or walking.

METHODS

Longitudinal data on 44 defined gross motor skills were collected on a large cohort of children with DS (n = 509) who received care at two referral centres that specialise in DS. Mastery was awarded when skills were observed directly by the physical therapist. Clinical data were retrospectively reviewed from a prospective patient clinic database and analysed.

RESULTS

Specific age of mastery of gross motor skills was assessed. The mean, standard deviation and median age in months of gross motor skill achievement for children with DS, along with the 5th, 25th, 75th and 95th percentiles, are provided for birth to walking skills and post walking skills. No statistically significant gender-by-age group difference was observed in the 44 skills.

CONCLUSIONS

This study provides a schedule of gross motor development for children with DS derived from data collected prospectively from a large population. The gross motor development of the child with DS can be assessed based on his or her performance relative to other children with DS enabling early identification of advanced, age appropriate or delayed development, allowing for appropriate referrals for targeted intervention.

Parent-child interaction: A micro-level sequential approach in children with a significant cognitive and motor developmental delay

BACKGROUND & AIMS

Previous research indicates that young children with a significant cognitive and motor developmental delay show low levels of interactive engagement, their parents are generally responsive towards them and these variables are positively correlated. Adapting a micro-level approach, we aim to go beyond macro-level and correlational analyses by charting the frequency, intra-individual co-occurrence and inter-individual temporal dependency of specific interactive behaviors.

METHODS & PROCEDURES

Twenty-nine parent-child dyads (with children aged 6-59 months) were video-taped during a 15-minute unstructured play situation. Based on a self-developed coding scheme, interactive behaviors were coded continuously and analyzed using a three-step sequential analysis approach.

OUTCOMES & RESULTS

Parents and children systematically combine either more socially-oriented or more object-oriented behaviors. Socially-oriented behaviors are less frequent in children, especially looking at and touching the partner occurs less. Socially- and object-oriented behavioral clusters are generally independent from each other and instigate/maintain the same type of behaviors in the interaction partner. While children's socially oriented behavior(al cluster)s seem to need a parental 'trigger', parents will more often independently engage with their child despite low child responsiveness.

CONCLUSIONS AND IMPLICATIONS

Further intervention-oriented research is needed to confirm this study's results and translate them into concrete guidelines for parents.

Automatic real-time gait event detection in children using deep neural networks

Annotation of foot-contact and foot-off events is the initial step in post-processing for most quantitative gait analysis workflows. If clean force plate strikes are present, the events can be automatically detected. Otherwise, annotation of gait events is performed manually, since reliable automatic tools are not available. Automatic annotation methods have been proposed for normal gait, but are usually based on heuristics of the coordinates and velocities of motion capture markers placed on the feet. These heuristics do not generalize to pathological gait due to greater variability in kinematics and anatomy of patients, as well as the presence of assistive devices. In this paper, we use a data-driven approach to predict foot-contact and foot-off events from kinematic and marker time series in children with normal and pathological gait. Through analysis of 9092 gait cycle measurements we build a predictive model using Long Short-Term Memory (LSTM) artificial neural networks. The best-performing model identifies foot-contact and foot-off events with an average error of 10 and 13 milliseconds respectively, outperforming popular heuristic-based approaches. We conclude that the accuracy of our approach is sufficient for most clinical and research applications in the pediatric population. Moreover, the LSTM architecture enables real-time predictions, enabling applications for real-time control of active assistive devices, orthoses, or prostheses. We provide the model, usage examples, and the training code in an open-source package.

[Fetal alcohol spectrum disorder. An underdiagnosed neuro-development disorder of uncertain prognosis]

Prenatal exposure to alcohol is the cause of cognitive and behavioural disorders grouped under the term fetal alcohol spectrum disorders (FASD). The long-term evolution of subjects with FASD is often unfavourable, especially in social and academic fields. Executive dysfunction is a hallmark deficit for children with FASD with increased rates of externalizing behaviours, such as aggressiveness and frequently delinquency in adolescence and adulthood. Deficits in social skills, empathy and communication ability are frequent observed among FASD. Prenatal exposure to alcohol is the most frequent cause of acquired and preventable neurodevelopmental disorder.

Continuous Intracranial Pressure Monitoring in 24 Microcephalic Children with Developmental Delay: A Significant Portion of Microcephalic Children with Developmental Delay Have High Intracranial Pressure

OBJECTIVE

The new direct gradual cranial expansion surgical technique has been used to treat children with postshunt microcephaly and slit ventricle syndrome. To evaluate the feasibility of this new surgical treatment, we studied intracranial pressure (ICP) in microcephalic children with developmental delay.

METHODS

Mean ICP, age, sex, head size, and developmental assessments were compared in 24 microcephalic children with developmental delay who had had continuous ICP monitoring.

RESULTS

Children studied included 9 boys and 15 girls with a mean age of 4.9 ± 2.0 years. Mean ICP was 18.7 ± 8.6 mm Hg. Children with high ICP had significantly lower age and higher B wave ratios than children with low ICP. There were no statistically significant differences in developmental scores and head sizes between children with high ICP and children with low ICP. In multiple linear regression analysis, we observed significantly increased risk of mean ICP elevation by B wave ratio and developmental score and decreased risk of mean ICP elevation by age, but not significantly increased risk of mean ICP elevation by head circumferences (z score).

CONCLUSIONS

Our findings suggest that a portion of microcephalic children with developmental delay have high ICP that cannot be expected from head sizes, and high ICP has decreasing tendency with age.

Do Active Video Games Improve Motor Function in People With Developmental Disabilities? A Meta-analysis of Randomized Controlled Trials

OBJECTIVE

To conduct a meta-analysis to examine the effectiveness of active video games (AVGs) interventions on motor function in people with developmental disabilities.

DATA SOURCES

An electronic search of 7 databases (PubMed, EbscoHost, Informit, Scopus, ScienceDirect, Proquest, PsychInfo) was conducted for randomized controlled trials (RCTs) evaluating AVGs to improve motor function in people with developmental disability, published through to May 2018.

STUDY SELECTION

Only articles in a peer-reviewed journal in English were selected and screened by 2 independent reviewers for RCTs that compared AVGs to conventional therapy. Twelve RCTs involving 370 people with developmental disabilities met the inclusion criteria for quantitative analysis.

DATA EXTRACTION

Two independent reviewers assessed risk of bias and study quality using the Egger's R, grading of recommendation, assessment, development and evaluation, and Template for Intervention Description and Replication checklists.

DATA SYNTHESIS

Three meta-analyses revealed a large effect size for AVGs to improve gross motor skills (Hedges' g=0.833, 95% confidence interval [95% CI]=0.247-1.420), small to medium effects for balance (g=0.458, 95% CI=0.023-0.948), and a small, nonsignificant effect for functional mobility (g=0.425, 95% CI= -0.03 to 0.881). Training frequency (ie, number of sessions per week) moderated the effect of AVGs on motor function in people with developmental disabilities.

CONCLUSION

We conclude that AVGs show task-specific effectiveness for gross motor skills but the effects are moderated by training intensity. However, because of the low number of trials, diverse diagnoses, variable dosage, and multiple outcome measures of the included trials, these results need to be interpreted with caution.

Personal characteristics and outcomes of individuals with developmental disabilities who need support for self-injurious behaviour

BACKGROUND

For people with intellectual and developmental disabilities, self-injurious behaviour (SIB) can have serious negative effects on both health and quality of life. This descriptive analysis will provide information on the characteristics and outcomes of a subsample of individuals who are identified as needing some or extensive support for SIB in the National Core Indicators Adult Consumer Survey sample.

METHODS

The data for this analysis come from states that participated in the 2015-2016 data collection cycle of National Core Indicators Adult Consumer Survey which is a face-to-face survey of adults receiving services through state developmental disability agencies.

RESULTS

The characteristics and outcomes of individuals who need at least some support for SIB differ from those of individuals with intellectual and developmental disabilities who do not need support for SIB. Individuals with SIB support needs, for example, tend to live in more structured settings, have fewer relationships, less inclusion in their communities and poorer employment outcomes.

CONCLUSIONS

The exploratory descriptive analysis concludes with suggested recommendations for more standardised definitions of SIB in public systems, enhanced behaviour plan protocols and the need for additional research.

Metabolism of amino acid neurotransmitters: the synaptic disorder underlying inherited metabolic diseases

Amino acids are involved in various metabolic pathways and some of them also act as neurotransmitters. Since biosynthesis of L-glutamate and γ-aminobutyric acid (GABA) requires 2-oxoglutarate while 3-phosphoglycerate is the precursor of L-glycine and D-serine, evolutionary selection of these amino acid neurotransmitters might have been driven by their capacity to provide important information about the glycolytic pathway and Krebs cycle. Synthesis and recycling of amino acid neurotransmitters as well as composition and function of their receptors are often compromised in inherited metabolic diseases. For instance, increased plasma L-phenylalanine concentrations impair cerebral biosynthesis of protein and bioamines in phenylketonuria, while elevated cerebral L-phenylalanine directly acts via ionotropic glutamate receptors. In succinic semialdehyde dehydrogenase deficiency, the neurotransmitter GABA and neuromodulatory γ-hydroxybutyric acid are elevated. Chronic hyperGABAergic state results in progressive downregulation of GABA_A and GABA_B receptors and impaired mitophagy. In glycine encephalopathy, the neurological phenotype is precipitated by L-glycine acting both via cortical NMDA receptors and glycine receptors in spinal cord and brain stem neurons. Serine deficiency syndromes are biochemically characterized by decreased biosynthesis of L-serine, an important neurotrophic factor, and the neurotransmitters D-serine and L-glycine. Supplementation with L-serine and L-glycine has a positive effect on seizure frequency and spasticity, while neurocognitive development can only be improved if treatment starts in utero or immediately postnatally. With novel techniques, the study of synaptic dysfunction in inherited metabolic diseases has become an emerging research field. More and better therapies are needed for these difficult-to-treat diseases.

Using a Functional Analysis Followed by Differential Reinforcement and Extinction to Reduce Challenging Behaviors in Children With Smith-Magenis Syndrome

Smith-Magenis syndrome (SMS) is a genetic disorder, commonly caused by a 17p11.2 deletion, affecting the Retinoic Acid Induced 1 gene. It affects approximately 1 in 25,000 individuals, with over 90% engaging in challenging behaviors. Function-based treatments, using the principles of applied behavior analysis, have consistently been shown to decrease challenging behaviors exhibited by individuals with developmental delays. However, additional research is needed to determine the effects of these interventions with specific diagnostic subsets, including SMS. The current study identified the function of challenging behavior for 2 children with SMS and found a function-based treatment, consisting of differential reinforcement and extinction, reduced challenging behavior for both.

Predictive accuracy of cerebroplacental ratio for adverse perinatal and neurodevelopmental outcomes in suspected fetal growth restriction: systematic review and meta-analysis

OBJECTIVE

The cerebroplacental ratio (CPR) has been proposed for the routine surveillance of pregnancies with suspected fetal growth restriction (FGR), but the predictive performance of this test is unclear. The aim of this study was to determine the accuracy of CPR for predicting adverse perinatal and neurodevelopmental outcomes in suspected FGR.

METHODS

PubMed, EMBASE, CINAHL and Lilacs were searched from inception to 31 July 2017 for cohort or cross-sectional studies reporting on the accuracy of CPR for predicting adverse perinatal and/or neurodevelopmental outcomes in singleton pregnancies with FGR suspected antenatally based on sonographic parameters. Summary receiver-operating characteristics (ROC) curves, pooled sensitivities and specificities, and summary likelihood ratios (LRs) were generated.

RESULTS

Twenty-two studies (including 4301 women) met the inclusion criteria. Summary ROC curves showed that the best predictive accuracy of CPR was for perinatal death and the worst was for neonatal acidosis, with areas under the summary ROC curves of 0.83 and 0.57, respectively. The predictive accuracy of CPR was moderate to high for perinatal death (pooled sensitivity and specificity of 93% and 76%, respectively, and summary positive and negative LRs of 3.9 and 0.09, respectively) and low for composite of adverse perinatal outcomes, Cesarean section for non-reassuring fetal status, 5-min Apgar score < 7, admission to the neonatal intensive care unit, neonatal acidosis and neonatal morbidity, with summary positive and negative LRs ranging from 1.1 to 2.5 and 0.3 to 0.9, respectively. An abnormal CPR result had moderate accuracy for predicting small-for-gestational age at birth (summary positive LR of 7.4). CPR had a higher predictive accuracy in pregnancies with suspected early-onset FGR. No study provided data for assessing the predictive accuracy of CPR for adverse neurodevelopmental outcome.

CONCLUSION

CPR appears to be useful in predicting perinatal death in pregnancies with suspected FGR. Nevertheless, before incorporating CPR into the routine clinical management of suspected FGR, randomized controlled trials should assess whether the use of CPR reduces perinatal death or other adverse perinatal outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Association analysis between four vitamin D receptor gene polymorphisms and developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a congenital condition characterized by abnormality in acetabulum size and/or shape. The incidence rate of DDH differs between different populations with risk factors including positive family history, breech presentation, sex, firstborn status, side of the hip, mode of delivery and oligohydramnios. It is recognized that DDH has a genetic component that exhibit autosomal dominant patterns. Many candidate genes have been studied and found to be associated with the disease; most of them are normally involved in cartilage development and joint metabolism. In this study, the association of four single-nucleotide polymorphisms (SNPs) (rs731236, rs1544410, rs7975232 and rs2228570) in the vitamin D receptor (VDR) gene was studied by a case-control analysis. The study sample involves 50 cases with confirmed DDH presentation and 50 nonDDH controls. SNPs were genotyped using conventional polymerase chain reaction (PCR) and restriction fragment-length polymorphism (RFLP) techniques. Genotype and allele frequencies were analysed using SPSS software. No significant associations were found between the VDR polymorphisms analysed and DDH. Further work need to be performed using genomewide analysis to elucidate the genetic basis of DDH.

Effects of a family-centered workshop for children with developmental delays

This study investigated the effects of a short-term family-centered workshop for children with developmental delays.This study was conducted in a rehabilitation outpatient clinic of a teaching hospital. We recruited 30 children with developmental delays and their parents as the study group and 57 age- and sex-matched children with typical development and their parents as the control group. The workshop was conducted for the children with developmental delays and their parents in the form of one 2-hour session per week for 6 weeks by health and education professionals by using a family-centered multidisciplinary approach. The Mandarin-Chinese Communicative Developmental Inventory and Peabody Developmental Motor Scales-Second Edition were used to assess the communication and motor skills of the children with developmental delays. The parent form of the Pediatric Outcomes Data Collection Instrument, Child Health Questionnaire, Pediatric Quality of Life (PedsQL) Inventory, and PedsQL Family Impact Module were administered to the parents of both groups.On study commencement, no significant differences were noted in functional performance and family impact between the children with developmental delays and those without delays. The children with developmental delays had lower health and health-related quality of life (HRQOL) scores than the children with typical development. Following the workshop, the study group exhibited significant improvements in physical health (94.2 vs 80.2, effect size: 1.00, P = .026), global function (94.8 vs 78.7, effect size: 0.88, P = .006), impact of the child's health on parental HRQOL (85.0 vs 70.4, effect size: 0.81, P = .043), and parental HRQOL (81.3 vs 65.0, effect size: 0.81, P = .015). No significant differences were recorded in function, health, HRQOL, or family impact between the children with developmental delays and those with typical development after 6 weeks.The multidisciplinary short-term family-centered workshop for children with developmental delays improved the children's physical health and global functional skills, and it reduced the impact of the child's health on parental HRQOL while also improving parental HRQOL.

Clinician vs. Machine: Estimating Vocalizations Rates in Young Children With Developmental Disorders

PURPOSE

The purpose of this study was to investigate the reliability of an automated language analysis system, the Language Environment Analysis (LENA), compared with a human transcriber to determine the rate of child vocalizations during recording sessions that were significantly shorter than recommended for the automated device.

METHOD

Participants were 6 nonverbal male children between the ages of 28 and 46 months. Two children had autism diagnoses, 2 had Down syndrome, 1 had a chromosomal deletion, and 1 had developmental delay. Participants were recorded by the LENA digital language processor during 14 play-based interactions with a responsive adult. Rate of child vocalizations during each of the 84 recordings was determined by both a human transcriber and the LENA software.

RESULTS

A statistically significant difference between the 2 methods was observed for 4 of the 6 participants. Effect sizes were moderate to large. Variation in syllable structure did not explain the difference between the 2 methods. Vocalization rates from the 2 methods were highly correlated for 5 of the 6 participants.

CONCLUSIONS

Estimates of vocalization rates from nonverbal children produced by the LENA system differed from human transcription during sessions that were substantially shorter than the recommended recording length. These results confirm the recommendation of the LENA Foundation to record sessions of at least 1 hr.

Neurodevelopment of 24 children born in Brazil with congenital Zika syndrome in 2015: a case series study

OBJECTIVE

To describe the neurodevelopment of children with congenital Zika syndrome during the second year of life.

DESIGN

Case series study.

SETTING

Instituto de Medicina Integral Professor Fernando Figueira (IMIP), Pernambuco, Brazil.

PARTICIPANTS

24 children with congenital Zika syndrome born with microcephaly during the Zika outbreak in Brazil in 2015 and followed up at the IMIP during their second year of life.

MAIN OUTCOME MEASURE

Denver Developmental Screening Test II, head circumference and clinical neurological examination.

RESULTS

All children presented neurodevelopmental delay: for an average chronological age of 19.9 months, language was equivalent to that of age 2.1 months, gross motor 2.7 months, fine motor/adaptive 3.1 months and personal/social 3.4 months. Head circumference remained below the third percentile for age and gender, and growth rate up to the second year of life was 10.3 cm (expected growth 13 cm). Muscle tone was increased in 23 (95.5%) of 24 children, musculotendinous reflexes were increased in the whole sample and clonus was present in 18 (77.3%) of 24 children. All children except one had epilepsy.

CONCLUSION

Children born with microcephaly associated with congenital Zika virus have a significant neurodevelopmental delay.

Functional variants in TBX2 are associated with a syndromic cardiovascular and skeletal developmental disorder

The 17 genes of the T-box family are transcriptional regulators that are involved in all stages of embryonic development, including craniofacial, brain, heart, skeleton and immune system. Malformation syndromes have been linked to many of the T-box genes. For example, haploinsufficiency of TBX1 is responsible for many structural malformations in DiGeorge syndrome caused by a chromosome 22q11.2 deletion. We report four individuals with an overlapping spectrum of craniofacial dysmorphisms, cardiac anomalies, skeletal malformations, immune deficiency, endocrine abnormalities and developmental impairments, reminiscent of DiGeorge syndrome, who are heterozygotes for TBX2 variants. The p.R20Q variant is shared by three affected family members in an autosomal dominant manner; the fourth unrelated individual has a de novo p.R305H mutation. Bioinformatics analyses indicate that these variants are rare and predict them to be damaging. In vitro transcriptional assays in cultured cells show that both variants result in reduced transcriptional repressor activity of TBX2. We also show that the variants result in reduced protein levels of TBX2. Heterologous over-expression studies in Drosophila demonstrate that both p.R20Q and p.R305H function as partial loss-of-function alleles. Hence, these and other data suggest that TBX2 is a novel candidate gene for a new multisystem malformation disorder.