Down's syndrome

Dysregulation of the Immune System in a Natural History Study of 1299 Individuals with Down Syndrome

Dysregulation of the immune system in individuals with Down syndrome is thought to play a major role in the pathophysiology of many clinical presentations. This natural history of disease study took a comprehensive evaluation of the prevalence of different immune related diagnoses in a cohort of 1299 patients with Down syndrome compared to a 2605 patient control cohort at the Mount Sinai Health System in New York, NY over the past 18 years. We conducted a stepwise analysis of the odds of receiving a diagnosis at the Chapter, Sub-chapter and Diagnosis level of the ICD-CM-10 code system. Individuals in our Down syndrome cohort had higher odds of a diagnosis with inflammatory and autoimmune presentations such as Alopecia areata (OR 6.06, p = 0.01), Other sepsis (OR 4.79, p < 0.001, Purpura and other hemorrhagic conditions (OR 2.31, p < 0.001), and Rosacea (OR 3.11, p < 0.001). They also presented with lower odds of a diagnosis of Herpesviral infection (OR 0.42, p = 0.01), and Viral warts (OR 0.51, p = 0.04). We posit that dysregulation of the immune system in individuals with Down syndrome has impact on infectious diseases, including lowering the incidence of viral disease and increasing its severity. Our data also suggests inflammation and autoimmune mediated diseases, in particular of the skin, are exacerbated in individuals with Down syndrome. Finally, there may be a need for greater clinical attention to non-emergent conditions within the Down syndrome patient population as those can also greatly affect quality of life.

Integrative multi-omic analysis reveals conserved cell-projection deficits in human Down syndrome brains

Down syndrome (DS) is the most common genetic cause of cognitive disability. However, it is largely unclear how triplication of a small gene subset may impinge on diverse aspects of DS brain physiopathology. Here, we took a multi-omic approach and simultaneously analyzed by RNA-seq and proteomics the expression signatures of two diverse regions of human postmortem DS brains. We found that the overexpression of triplicated genes triggered global expression dysregulation, differentially affecting transcripts, miRNAs, and proteins involved in both known and novel biological candidate pathways. Among the latter, we observed an alteration in RNA splicing, specifically modulating the expression of genes involved in cytoskeleton and axonal dynamics in DS brains. Accordingly, we found an alteration in axonal polarization in neurons from DS human iPSCs and mice. Thus, our study provides an integrated multilayer expression database capable of identifying new potential targets to aid in designing future clinical interventions for DS.

Phenotyping Down syndrome: discovery and predictive modelling with electronic medical records

BACKGROUND

Individuals with Down syndrome (DS) have a heightened risk for various co-occurring health conditions, including congenital heart disease (CHD). In this two-part study, electronic medical records (EMRs) were leveraged to examine co-occurring health conditions among individuals with DS (Study 1) and to investigate health conditions linked to surgical intervention among DS cases with CHD (Study 2).

METHODS

De-identified EMRs were acquired from Vanderbilt University Medical Center and facilitated creating a cohort of N = 2282 DS cases (55% females), along with comparison groups for each study. In Study 1, DS cases were one-by-two sex and age matched with samples of case-controls and of individuals with other intellectual and developmental difficulties (IDDs). The phenome-disease association study (PheDAS) strategy was employed to reveal co-occurring health conditions in DS versus comparison groups, which were then ranked for how often they are discussed in relation to DS using the PubMed database and Novelty Finding Index. In Study 2, a subset of DS individuals with CHD [N = 1098 (48%)] were identified to create longitudinal data for N = 204 cases with surgical intervention (19%) versus 204 case-controls. Data were included in predictive models and assessed which model-based health conditions, when more prevalent, would increase the likelihood of surgical intervention.

RESULTS

In Study 1, relative to case-controls and those with other IDDs, co-occurring health conditions among individuals with DS were confirmed to include heart failure, pulmonary heart disease, atrioventricular block, heart transplant/surgery and primary pulmonary hypertension (circulatory); hypothyroidism (endocrine/metabolic); and speech and language disorder and Alzheimer's disease (neurological/mental). Findings also revealed more versus less prevalent co-occurring health conditions in individuals with DS when comparing with those with other IDDs. Findings with high Novelty Finding Index were abnormal electrocardiogram, non-rheumatic aortic valve disorders and heart failure (circulatory); acid-base balance disorder (endocrine/metabolism); and abnormal blood chemistry (symptoms). In Study 2, the predictive models revealed that among individuals with DS and CHD, presence of health conditions such as congestive heart failure (circulatory), valvular heart disease and cardiac shunt (congenital), and pleural effusion and pulmonary collapse (respiratory) were associated with increased likelihood of surgical intervention.

CONCLUSIONS

Research efforts using EMRs and rigorous statistical methods could shed light on the complexity in health profile among individuals with DS and other IDDs and motivate precision-care development.

Early Chronic Fluoxetine Treatment of Ts65Dn Mice Rescues Synaptic Vesicular Deficits and Prevents Aberrant Proteomic Alterations

Down syndrome (DS) is the most common form of inherited intellectual disability caused by trisomy of chromosome 21, presenting with intellectual impairment, craniofacial abnormalities, cardiac defects, and gastrointestinal disorders. The Ts65Dn mouse model replicates many abnormalities of DS. We hypothesized that investigation of the cerebral cortex of fluoxetine-treated trisomic mice may provide proteomic signatures that identify therapeutic targets for DS. Subcellular fractionation of synaptosomes from cerebral cortices of age- and brain-area-matched samples from fluoxetine-treated vs. water-treated trisomic and euploid male mice were subjected to HPLC-tandem mass spectrometry. Analysis of the data revealed enrichment of trisomic risk genes that participate in regulation of synaptic vesicular traffic, pre-synaptic and post-synaptic development, and mitochondrial energy pathways during early brain development. Proteomic analysis of trisomic synaptic fractions revealed significant downregulation of proteins involved in synaptic vesicular traffic, including vesicular endocytosis (CLTA, CLTB, CLTC), synaptic assembly and maturation (EXOC1, EXOC3, EXOC8), anterograde axonal transport (EXOC1), neurotransmitter transport to PSD (SACM1L), endosomal-lysosomal acidification (ROGDI, DMXL2), and synaptic signaling (NRXN1, HIP1, ITSN1, YWHAG). Additionally, trisomic proteomes revealed upregulation of several trafficking proteins, involved in vesicular exocytosis (Rab5B), synapse elimination (UBE3A), scission of endocytosis (DBN1), transport of ER in dendritic spines (MYO5A), presynaptic activity-dependent bulk endocytosis (FMR1), and NMDA receptor activity (GRIN2A). Chronic fluoxetine treatment of Ts65Dn mice rescued synaptic vesicular abnormalities and prevented abnormal proteomic changes in adult Ts65Dn mice, pointing to therapeutic targets for potential treatment of DS.

In vivo quasi-elastic light scattering detects molecular changes in the lenses of adolescents with Down syndrome

Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-β (Aβ) peptides and amyloid pathology in the brain and comorbid early-onset Aβ amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.

Homogeneity in Motor Competence Among Youths With Intellectual Disability With and Without Down Syndrome

PURPOSE

To determine if there is a homogeneity of scores for youth with intellectual disability (ID) with and without Down syndrome (DS) in 19 test items of motor competence from the Bruininks-Oseretsky Test of Motor Proficiency-Second Edition (BOT-2). Homogeneity was defined as the means for each of the 19 test items scores by sex and the presence or absence of DS sharing the same population mean.

METHOD

Participants were 622 youth with ID aged 6 to 21 years. Items for bilateral coordination, balance, and upper limb coordination were examined using the BOT-2.

RESULTS

For all 19 BOT-2 items, means between youth with and without DS did not differ from the population mean.

CONCLUSION

These results potentiate the development of expected BOT-2 motor competence scores for youth with ID independent of the presence of DS for clinical practice.

From understanding to action: Exploring molecular connections of Down syndrome to Alzheimer's disease for targeted therapeutic approach

Down syndrome (DS) is caused by a third copy of chromosome 21. Alzheimer's disease (AD) is a neurodegenerative condition characterized by the deposition of amyloid-beta (Aβ) plaques and neurofibrillary tangles in the brain. Both disorders have elevated Aβ, tau, dysregulated immune response, and inflammation. In people with DS, Hsa21 genes like APP and DYRK1A are overexpressed, causing an accumulation of amyloid and neurofibrillary tangles, and potentially contributing to an increased risk of AD. As a result, people with DS are a key demographic for research into AD therapeutics and prevention. The molecular links between DS and AD shed insights into the underlying causes of both diseases and highlight potential therapeutic targets. Also, using biomarkers for early diagnosis and treatment monitoring is an active area of research, and genetic screening for high-risk individuals may enable earlier intervention. Finally, the fundamental mechanistic parallels between DS and AD emphasize the necessity for continued research into effective treatments and prevention measures for DS patients at risk for AD. Genetic screening with customized therapy approaches may help the DS population in current clinical studies and future biomarkers.

Lipid Profile, Eating Habit, and Physical Activity in Children with Down Syndrome: A Prospective Study

Children with Down Syndrome (DS) frequently undergo health challenges, including a higher prevalence of overweight and obesity. We aimed to evaluate the impact of dietary and physical advice provided by a specialized pediatrician over two years. In this prospective study, 44 children with DS, aged 2 to 17, underwent outpatient follow-up visits every six months between December 2020 and May 2023. Dietary habits, physical activities, anthropometric data, and laboratory results were recorded at baseline and 2-year follow-up. Adherence to the Mediterranean diet and physical activity were investigated using the 'KIDMED' and 'Godin-Shepard Leisure-Time' questionnaires, respectively, completed by the parents of the children. Venous blood samples were taken to determine the lipid profile. A significant reduction in BMI z-scores (p = 0.006) and an improvement in Godin-Shepard questionnaire scores (p = 0.0004) were observed. On the other hand, the lipid profile worsened, with an increase in LDL-c (p = 0.04) and a decrease in HDL-c (p = 0.03). Children with DS may benefit from an educational program on nutrition and physical activity to optimize weight control. Different interventions should target the lipid profile. Preventive intervention and follow-up by the pediatrician are essential for DS, which should continue into adulthood.

A Novel Physiotherapy Approach for Enhancing Mobility in a 53-Year-Old With Down Syndrome: A Case Report

Down syndrome (DS) is a genetic condition developing from a supplementary chromosome 21, referred to as trisomy 21. It ranks among the most prevalent developmental disabilities. People with DS often live inactive lifestyles, not meeting the weekly physical activity guidelines. With age, they face increased risks of cardiovascular disease and osteoporosis, as well as neurological and orthopedic concerns. Physiotherapy is especially important for improving balance, coordination, strength, and endurance in adults over the age of 50. Our approach consisted of a three-week regimen that included strengthening exercises based on the DeLorme strength training principle, balance exercises with perturbation and treadmill training, and coordination exercises with equilibrium and non-equilibrium movements. We evaluated outcomes using measures such as the Berg Balance Scale, Timed Up and Go test, and Functional Independence Measure, which were performed before and after the physiotherapy intervention. We present a case study of a 53-year-old woman to demonstrate the importance of physiotherapy in making lifestyle changes and improving strength, balance, and endurance, thereby improving overall quality of life through tailored interventions.

The role of Down syndrome cell adhesion molecule in Down syndrome

Down syndrome (DS) is caused by the presence of an extra copy of the entire or a portion of human chromosome 21 (HSA21). This genomic alteration leads to elevated expression of numerous HSA21 genes, resulting in a variety of health issues in individuals with DS. Among the genes located in the DS "critical region" of HSA21, Down syndrome cell adhesion molecule (DSCAM) plays an important role in neuronal development. There is a growing body of evidence underscoring DSCAM's involvement in various DS-related disorders. This review aims to provide a concise overview of the established functions of DSCAM, with a particular focus on its implications in DS. We delve into the roles that DSCAM plays in DS-associated diseases. In the concluding section of this review, we explore prospective avenues for future research to further unravel DSCAM's role in DS and opportunities for therapeutic treatments.

Navigating Complexity: A Rare Case of Down Syndrome With Dural Venous Thrombosis in a Neonate

This case report presents a unique clinical scenario of a 2 kg male neonate with Down syndrome complicated by dural venous thrombosis. Born via normal vaginal delivery, the infant exhibited syndromic features characteristic of Down syndrome, necessitating admission to the neonatal intensive care unit (NICU) for respiratory distress. Confirmatory karyotyping established the diagnosis. Subsequent complications included germinal matrix haemorrhage, hypoxic-ischemic encephalopathy, and aspiration pneumonia. An MRI revealed dural venous thrombosis in the left transverse sinus, an uncommon manifestation in neonates with Down syndrome. Multidisciplinary management involved respiratory support, antibiotic therapy, and neurophysiotherapy. Infectious complications, including Klebsiella pneumoniae growth, required tailored antibiotic intervention. Despite intubation and CO2 retention challenges, the neonate improved and was ultimately discharged with favourable anthropometric measurements. This case underscores the importance of a comprehensive approach to neonatal care in the context of Down syndrome, emphasising the need for early recognition and management of rare complications such as venous thrombosis. The positive outcome highlights the efficacy of a multidisciplinary strategy in addressing complex neonatal conditions.

Understanding the genetic mechanisms and cognitive impairments in Down syndrome: towards a holistic approach

The most common genetic cause of intellectual disability is Down syndrome (DS), trisomy 21. It commonly results from three copies of human chromosome 21 (HC21). There are no mutations or deletions involved in DS. Instead, the phenotype is caused by altered transcription of the genes on HC21. These transcriptional variations are responsible for a myriad of symptoms affecting every organ system. A very debilitating aspect of DS is intellectual disability (ID). Although tremendous advances have been made to try and understand the underlying mechanisms of ID, there is a lack of a unified, holistic view to defining the cause and managing the cognitive impairments. In this literature review, we discuss the mechanisms of neuronal over-inhibition, abnormal morphology, and other genetic factors in contributing to the development of ID in DS patients and to gain a holistic understanding of ID in DS patients. We also highlight potential therapeutic approaches to improve the quality of life of DS patients.

Cross-Sectional Analysis of Caregiver-Reported Expressive Language Profiles and Associated Covariates in Individuals with Down Syndrome

OBJECTIVE

To describe the distribution of expressive language abilities of individuals with Down syndrome (DS) in a clinical sample and characterize demographic, environmental, and medical factors associated with varying expressive language profiles.

METHODS

Cross-sectional analysis was completed on a sample of 345 individuals with DS between the ages of 4 and 22 years who were enrolled into a longitudinal clinical database between March 2018 and August 2021. Expressive language-related items on a standardized caregiver-reported questionnaire assessing domains of functioning in neurodevelopmental disorders were used to conduct latent variable modeling and determine caregiver-reported expressive language (CREL) classes across the sample. Linear regression was used to explore associations between CREL classes and predictor variables.

RESULTS

Latent variable modeling revealed 3 distinct classes of CREL abilities representing higher, middle, and lower CREL. Individuals in the lower CREL class were more likely to be female, to use sign language or visual communication systems, have reduced pronunciation, attend private or residential school, and to be in a substantially separate classroom. Membership was not predicted by complex medical histories or co-occurring neurodevelopmental diagnoses.

CONCLUSION

Caregiver-reported expressive language abilities in a cohort of individuals with DS were variable, with most of the individuals belonging to higher or middle CREL classes, relative to one another. Additional studies are indicated to understand factors that predict higher expressive language ability and explore how to direct services to individuals who are at risk of more profound language delays.

Informing Clinical Practice Guidelines for Children and Youth With Down Syndrome: A Survey of Key Partners

PURPOSE

The purpose of this work was to describe input from key partners to inform the scope and priorities for a clinical practice guideline (CPG) pertaining to physical therapy services provided to children and youth with Down syndrome (DS).

METHODS

A 68-item survey was completed by interventionists and parents (n = 296) of children and youth with DS.

RESULTS

The most prevalent physical therapy interventions currently being performed included tummy time, postural control activities, activity-based interventions, and play-based interventions. Key partners agreed on the importance of specific clinical outcomes, needing guidance on frequency and dosage of interventions, common barriers to physical therapy intervention, and needing information for discharge criteria in a future CPG.

CONCLUSIONS

The results of this survey have given the CPG committee the necessary information to inform the CPG process for children and youth with DS.

Unraveling Down Syndrome: From Genetic Anomaly to Artificial Intelligence-Enhanced Diagnosis

Down syndrome arises from chromosomal non-disjunction during gametogenesis, resulting in an additional chromosome. This anomaly presents with intellectual impairment, growth limitations, and distinct facial features. Positive correlation exists between maternal age, particularly in advanced cases, and the global annual incidence is over 200,000 cases. Early interventions, including first and second-trimester screenings, have improved DS diagnosis and care. The manifestations of Down syndrome result from complex interactions between genetic factors linked to various health concerns. To explore recent advancements in Down syndrome research, we focus on the integration of artificial intelligence (AI) and machine learning (ML) technologies for improved diagnosis and management. Recent developments leverage AI and ML algorithms to detect subtle Down syndrome indicators across various data sources, including biological markers, facial traits, and medical images. These technologies offer potential enhancements in accuracy, particularly in cases complicated by cognitive impairments. Integration of AI and ML in Down syndrome diagnosis signifies a significant advancement in medical science. These tools hold promise for early detection, personalized treatment, and a deeper comprehension of the complex interplay between genetics and environmental factors. This review provides a comprehensive overview of neurodevelopmental and cognitive profiles, comorbidities, diagnosis, and management within the Down syndrome context. The utilization of AI and ML represents a transformative step toward enhancing early identification and tailored interventions for individuals with Down syndrome, ultimately improving their quality of life.

Dysregulation of the Immune System in a Natural History Study of 1299 Individuals with Down Syndrome

Dysregulation of the immune system in individuals with Down syndrome is thought to play a major role in the pathophysiology of many clinical presentations. This natural history of disease study took a comprehensive evaluation of the prevalence of different immune related diagnoses in a cohort of 1299 patients with Down syndrome compared to a 2605 control cohort of patients without Down syndrome at Mount Sinai Health System in NY, NY over the past 18 years. We conducted a stepwise analysis of the odds of receiving a diagnosis at the Chapter, Sub-chapter and Diagnosis level of the ICD-CM-10 code system. Individuals in our Down syndrome cohort had higher odds of a diagnosis with inflammatory and autoimmune presentations such as Alopecia areata (OR 6.06, p = 0.01), Other sepsis (OR 4.79, p < 0.001, Purpura and Other hemorrhagic conditions (OR 2.31, p < 0.001), and Rosacea (OR 3.11, p < 0.001). They also presented with lower odds of a diagnosis of Herpesviral infection (OR 0.42, p = 0.01), and Viral warts (OR 0.51, p = 0.04). We posit that dysregulation of the immune system in individuals with Down syndrome has impact on infectious diseases, including lowering the incidence of viral disease, and increasing its severity. Our data also suggests inflammation and autoimmune mediated diseases, in particular of the skin, is exacerbated in individuals with Down syndrome. Finally, there may be a need for greater clinical attention to non-emergent conditions within the Down syndrome patient population as those can also greatly affect quality of life.

Co-occurring conditions in Down syndrome: Findings from a clinical database

Individuals with Down syndrome (DS) experience a range of medical and neurodevelopmental conditions, necessitating systematic study of their occurrence and impact on neurodevelopmental outcomes. We describe the prevalence and relationships of medical, neurodevelopmental (ND), and mental health (MH) conditions in children with DS. We created a prospective clinical database of individuals with DS, integrated into the workflow of a specialty Down Syndrome Program at a specialty pediatric referral hospital. Conditions were collected through caregiver- and clinician report at clinical visits (N = 599). We calculated frequencies of medical, ND, and MH conditions and then assessed the relationship between medical, ND, and MH conditions using frequencies and comparative statistics. The most frequent co-occurring conditions were vision (72.5%), ear/hearing (71.0%), gastrointestinal (61.3%), respiratory (45.6%), and feeding (33.6%) problems, with variation in frequency by age. ND and MH conditions were reported in one quarter, most commonly autism spectrum disorder and attention-deficit/hyperactivity disorder. Those with ND and MH conditions had greater frequency of medical conditions, with highest rates of vision, ear/hearing, and gastrointestinal issues, and CHD. Systematically collected clinical data in a large cohort of children with DS reveals high prevalence of several co-occurring medical, ND, and MH conditions. Clinical care requires an understanding of the complex relationship between medical conditions and neurodevelopment.

Motor Skills and Executive Functions in Pediatric Patients with Down Syndrome: A Challenge for Tailoring Physical Activity Interventions

Down syndrome (DS) is one of the most common chromosomal disorders. In addition to this variety of dysmorphic features. DS is also associated with a wide range of diseases and related comorbidities affecting different organs and systems. These comorbidities, together with societal and environmental influences, have a negative impact on physical activity in people with DS. Low levels of physical activity and energy expenditure have been identified as crucial players in worsening the acquisition of motor skills and executive functions. Executive functions are critical for the many skills (creativity, flexibility, self-control, and discipline) impacting our quality of life and make it possible to control impulses, mentally play with ideas, and stay focused. We proposed a broad overview of the available literature regarding motor skills and executive functions in pediatric patients with DS to understand the specific challenges for tailoring physical activity interventions. Motor skill interventions are effective in improving motor competence and performance on cognitive, emotional, and physical aspects in children with DS. Interventions based on executive functions in DS subjects are effective to contrast the cognitive decline and improve the everyday use of executive functions in youth and adults. Targeted interventions are mandatory for maximizing the benefits of physical activity, minimizing potential risks, and ultimately improving the overall health outcomes and quality of life for individuals with DS.

Posterior urethral valves in patients with trisomy 21: Similar renal outcomes and rates of volitional voiding

INTRODUCTION

Posterior urethral valves (PUV) occur in patients with Down Syndrome (DS) at a rate of 3-4%; far higher than the general population. Our understanding of the relationship between PUVs and DS is in its infancy, with the majority of the literature consisting of case reports. In this study, we present the largest known series of DS patients with PUVs.

AIM

We hypothesized that patients with DS and PUVs would have worse functional bladder outcomes and renal outcomes when compared to PUV patients without DS.

STUDY DESIGN

We queried our prospectively managed multi-institutional database of PUV patients from 1990 to 2021. We identified patients with a concomitant diagnosis of DS and PUV. In addition, we performed a systematic review of the literature describing the presentation of children with PUV and DS. Patient demographics, renal outcomes, voiding habits, surgical interventions, and radiologic images were aggregated and analyzed.

RESULTS

Out of the 537 patients in our PUV database, we identified 18 patients with a concomitant diagnosis of PUV and DS, as well as 14 patients with a concomitant diagnosis of PUV and DS from the literature. DS and non-DS patients had a similar age at presentation, 31.5 days (2-731) and 17 (4-846), and length of follow up 6.32 years (2-11.2) and 6.98 (1-13). Both groups had similar nadir creatinines DS 0.43 (0.4-0.8), non-DS 0.31 (0.2-0.5) and similar rates of renal failure (DS 11.1% and non-DS 14.5%). With respect to bladder outcomes, a similar percentage of patients were volitionally voiding at last follow up (DS 72.2% and non-DS 72.3%). Our literature review corroborated these findings.

CONCLUSIONS

Patients with DS and PUV have similar renal outcomes to other PUV patients in terms of renal function, progression to renal failure, and probability of volitional voiding with continence. Given the increased rate of PUVs in the DS population, physicians should have a high index of suspicion for PUV when patients with DS present with voiding dysfunction.

Factors That Influence Physical Activity in Individuals With Down Syndrome: Perspectives of Guardians and Health Professionals

Identifying factors that influence physical activity (PA) among individuals with Down syndrome is essential for PA promotion. Insight can be gained from guardians and health professionals. The purpose of this study was to explore the perspectives of guardians and health professionals on facilitators and barriers of PA in individuals with Down syndrome. Interviews were conducted with 11 guardians (five mothers, four fathers, and two legal guardians) and 11 professionals (four PA specialists, three physical therapists, and four occupational therapists). Grounded theory was applied. Barriers and facilitators fit the levels of the ecological model of health behavior: (a) intrapersonal (perceived rewards), (b) interpersonal (interaction), (c) community (availability of programs), (d) organizational (school systems), and (e) policy (education). Guardians and professionals agreed on the importance of enjoyment, interaction, and programs to promote PA. Differences between groups were identified at the organizational and policy levels. PA in persons with Down syndrome is influenced by interactions between individual and environmental factors.

The CENP-A nucleosome: where and when it happens during the inner kinetochore's assembly

CENP-A is an essential histone variant that replaces the canonical H3 at the centromeres and marks these regions epigenetically. The CENP-A nucleosome is the specific building block of centromeric chromatin, and it is recognized by CENP-C and CENP-N, two components of the constitutive centromere-associated network (CCAN), the first protein layer of the kinetochore. Recent proposals of the yeast and human (h)CCAN structures position the assembly on exposed DNA, suggesting an elusive spatiotemporal recognition. We summarize the data on the structural organization of the CENP-A nucleosome and the binding of CENP-C and CENP-N. The latter posits an apparent contradiction in engaging the CENP-A nucleosome versus the CCAN. We propose a reconciliatory model for the assembly of CCAN on centromeric chromatin.

REST in the Road Map of Brain Development

Repressor element-1 silencing transcription factor (REST) or also known as neuron-restrictive silencing factor (NRSF), is the key initiator of epigenetic neuronal gene-expression modification. Identification of a massive number of REST-targeted genes in the brain signifies its broad involvement in maintaining the functionality of the nervous system. Additionally, REST plays a crucial role in conferring neuroprotection to the neurons against various stressors or insults during injuries. At the cellular level, nuclear localisation of REST is a key determinant for the functional transcriptional regulation of REST towards its target genes. Emerging studies reveal the implication of REST nuclear mislocalisation or dysregulation in several neurological diseases. The expression of REST varies depending on different types of neurological disorders, which has created challenges in the discovery of REST-targeted interventions. Hence, this review presents a comprehensive summary on the physiological roles of REST throughout brain development and its implications in neurodegenerative and neurodevelopmental disorders, brain tumours and cerebrovascular diseases. This review offers valuable insights to the development of potential therapeutic approaches targeting REST to improve pathologies in the brain. The important roles of REST as a key player in the nervous system development, and its implications in several neurological diseases.

Post-operative anterior diaphragmatic hernias in children with Trisomy 21 after cardiac surgery

Morgagni hernias account for less than 5% of congenital diaphragmatic hernias. They are characteristically retrosternal and bilateral, with right-sided predominance. An association between Trisomy 21 and diaphragmatic hernias resembling Morgagni hernia has been reported, but the effect of cardiac surgery on its formation has not been investigated. The purpose of this study was to determine whether there is a higher incidence of anterior diaphragmatic hernias in children with Trisomy 21 after cardiac surgery. We compared the prevalence of anterior diaphragmatic hernias in 92 patients with Trisomy 21 who underwent cardiac surgery with its prevalence in 100 children without Trisomy 21 who underwent cardiac surgery. All available CXRs of all children underwent revision for the presence of an anterior diaphragmatic hernia by a pediatric radiologist. Within the study group, four cases of an anterior diaphragmatic hernia were detected, all upon presentation to the emergency room due to breathing difficulties. No cases of an anterior diaphragmatic hernia were found in the control group (P = 0.0094).

CONCLUSIONS

A high index of suspicion for an anterior diaphragmatic hernia should be maintained in children with Trisomy 21 who have undergone cardiac surgery and present with breathing difficulty. If CXR findings are uncertain, UGI series and\or CT should be performed. In light of our findings, the surgical technique has been modified in patients with DS in our medical center.

WHAT IS KNOWN

• Several studies reported an association between Trisomy 21 and diaphragmatic hernia resembling Morgagni hernia, but the effect of cardiac surgery on its formation has not been investigated.

WHAT IS NEW

• There is a higher incidence of anterior diaphragmatic hernia resembling a Morgagni hernia in children with Trisomy 21 after cardiac surgery. • A high index of suspicion for an anterior diaphragmatic hernia should be maintained in children with Trisomy 21 who have undergone cardiac surgery and present with breathing difficulty. If CXR findings are uncertain, UGI series and\or CT should be performed.

RUN(X) out of blood: emerging RUNX1 functions beyond hematopoiesis and links to Down syndrome

BACKGROUND

RUNX1 is a transcription factor and a master regulator for the specification of the hematopoietic lineage during embryogenesis and postnatal megakaryopoiesis. Mutations and rearrangements on RUNX1 are key drivers of hematological malignancies. In humans, this gene is localized to the 'Down syndrome critical region' of chromosome 21, triplication of which is necessary and sufficient for most phenotypes that characterize Trisomy 21.

MAIN BODY

Individuals with Down syndrome show a higher predisposition to leukemias. Hence, RUNX1 overexpression was initially proposed as a critical player on Down syndrome-associated leukemogenesis. Less is known about the functions of RUNX1 in other tissues and organs, although growing reports show important implications in development or homeostasis of neural tissues, muscle, heart, bone, ovary, or the endothelium, among others. Even less is understood about the consequences on these tissues of RUNX1 gene dosage alterations in the context of Down syndrome. In this review, we summarize the current knowledge on RUNX1 activities outside blood/leukemia, while suggesting for the first time their potential relation to specific Trisomy 21 co-occurring conditions.

CONCLUSION

Our concise review on the emerging RUNX1 roles in different tissues outside the hematopoietic context provides a number of well-funded hypotheses that will open new research avenues toward a better understanding of RUNX1-mediated transcription in health and disease, contributing to novel potential diagnostic and therapeutic strategies for Down syndrome-associated conditions.

Odontoma and other congenital dental anomalies: Implications for forensic identification

Forensic odontology plays a crucial role in establishing the identity in mass disasters and criminal cases with high accuracy. Dental anomalies and features help in such situations. Congenital and developmental dental anomalies can be easily documented to establish distinctive and individualistic characteristics of an individual. The location, number of teeth involved, and the type of anomaly vary between individuals. Similarly, dental malformations also assist greatly in the identification process. Many types of dental anomalies have been studied in the past for their individualistic characteristics in forensic examinations. One such dental anomaly is odontoma, which is a benign odontogenic malformation. This malformation may also help in the identification of the deceased, when recorded and examined accurately. An odontome is a malformed teeth-like structures consisting of enamel, dentin, and pulpal tissue, formed due to the growth of completely differentiated epithelial and mesenchymal cells. If antemortem (AM) dental records incorporate information regarding odontomes and other dental anomalies, including in radiographs, orthopantomograms or microradiographs, positive identification may be established by comparison of these records with postmortem (PM) records. In the present communication, a rare case of compound composite odontoma in the anterior mandible with multiple denticles has been discussed with a brief overview of congenital and developmental dental anomalies. The authors emphasize the importance of such rare dental anomalies and malformations which may be used for identifying the deceased in mass disasters and forensic identification.

Machine learning based analysis for intellectual disability in Down syndrome

Down syndrome (DS) or trisomy 21 is the most common genetic cause of intellectual disability (ID), but a pathogenic mechanism has not been identified yet. Studying a complex and not monogenic condition such as DS, a clear correlation between cause and effect might be difficult to find through classical analysis methods, thus different approaches need to be used. The increased availability of big data has made the use of artificial intelligence (AI) and in particular machine learning (ML) in the medical field possible. The purpose of this work is the application of ML techniques to provide an analysis of clinical records obtained from subjects with DS and study their association with ID. We have applied two tree-based ML models (random forest and gradient boosting machine) to the research question: how to identify key features likely associated with ID in DS. We analyzed 109 features (or variables) in 106 DS subjects. The outcome of the analysis was the age equivalent (AE) score as indicator of intellectual functioning, impaired in ID. We applied several methods to configure the models: feature selection through Boruta framework to minimize random correlation; data augmentation to overcome the issue of a small dataset; age effect mitigation to take into account the chronological age of the subjects. The results show that ML algorithms can be applied with good accuracy to identify variables likely involved in cognitive impairment in DS. In particular, we show how random forest and gradient boosting machine produce results with low error (MSE <0.12) and an acceptable R2 (0.70 and 0.93). Interestingly, the ranking of the variables point to several features of interest related to hearing, gastrointestinal alterations, thyroid state, immune system and vitamin B12 that can be considered with particular attention for improving care pathways for people with DS. In conclusion, ML-based model may assist researchers in identifying key features likely correlated with ID in DS, and ultimately, may improve research efforts focused on the identification of possible therapeutic targets and new care pathways. We believe this study can be the basis for further testing/validating of our algorithms with multiple and larger datasets.

Dose imbalance of DYRK1A kinase causes systemic progeroid status in Down syndrome by increasing the un-repaired DNA damage and reducing LaminB1 levels

BACKGROUND

People with Down syndrome (DS) show clinical signs of accelerated ageing. Causative mechanisms remain unknown and hypotheses range from the (essentially untreatable) amplified-chromosomal-instability explanation, to potential actions of individual supernumerary chromosome-21 genes. The latter explanation could open a route to therapeutic amelioration if the specific over-acting genes could be identified and their action toned-down.

METHODS

Biological age was estimated through patterns of sugar molecules attached to plasma immunoglobulin-G (IgG-glycans, an established "biological-ageing-clock") in n = 246 individuals with DS from three European populations, clinically characterised for the presence of co-morbidities, and compared to n = 256 age-, sex- and demography-matched healthy controls. Isogenic human induced pluripotent stem cell (hiPSCs) models of full and partial trisomy-21 with CRISPR-Cas9 gene editing and two kinase inhibitors were studied prior and after differentiation to cerebral organoids.

FINDINGS

Biological age in adults with DS is (on average) 18.4-19.1 years older than in chronological-age-matched controls independent of co-morbidities, and this shift remains constant throughout lifespan. Changes are detectable from early childhood, and do not require a supernumerary chromosome, but are seen in segmental duplication of only 31 genes, along with increased DNA damage and decreased levels of LaminB1 in nucleated blood cells. We demonstrate that these cell-autonomous phenotypes can be gene-dose-modelled and pharmacologically corrected in hiPSCs and derived cerebral organoids. Using isogenic hiPSC models we show that chromosome-21 gene DYRK1A overdose is sufficient and necessary to cause excess unrepaired DNA damage.

INTERPRETATION

Explanation of hitherto observed accelerated ageing in DS as a developmental progeroid syndrome driven by DYRK1A overdose provides a target for early pharmacological preventative intervention strategies.

FUNDING

Main funding came from the "Research Cooperability" Program of the Croatian Science Foundation funded by the European Union from the European Social Fund under the Operational Programme Efficient Human Resources 2014-2020, Project PZS-2019-02-4277, and the Wellcome Trust Grants 098330/Z/12/Z and 217199/Z/19/Z (UK). All other funding is described in details in the "Acknowledgements".

Modifiable cardiovascular risk factors and genetics for targeted prevention of dementia

Dementia is a major global challenge for health and social care in the 21st century. A third of individuals >65 years of age die with dementia, and worldwide incidence numbers are projected to be higher than 150 million by 2050. Dementia is, however, not an inevitable consequence of old age; 40% of dementia may theoretically be preventable. Alzheimer's disease (AD) accounts for approximately two-thirds of dementia cases and the major pathological hallmark of AD is accumulation of amyloid-β. Nevertheless, the exact pathological mechanisms of AD remain unknown. Cardiovascular disease and dementia share several risk factors and dementia often coexists with cerebrovascular disease. In a public health perspective, prevention is crucial, and it is suggested that a 10% reduction in prevalence of cardiovascular risk factors could prevent more than nine million dementia cases worldwide by 2050. Yet this assumes causality between cardiovascular risk factors and dementia and adherence to the interventions over decades for a large number of individuals. Using genome-wide association studies, the entire genome can be scanned for disease/trait associated loci in a hypothesis-free manner, and the compiled genetic information is not only useful for pinpointing novel pathogenic pathways but also for risk assessments. This enables identification of individuals at high risk, who likely will benefit the most from a targeted intervention. Further optimization of the risk stratification can be done by adding cardiovascular risk factors. Additional studies are, however, highly needed to elucidate dementia pathogenesis and potential shared causal risk factors between cardiovascular disease and dementia.

Bladder and bowel dysfunction in Down syndrome with neural tube defect: case report and review of the literature

BACKGROUND

Down syndrome is a genetic disorder caused by trisomy of chromosome 21 and characterized by an increased risk of multiorgan involvement. In Down syndrome children, functional constipation and lower urinary tract infections have been described, together with higher risk for incontinence and delayed sphincter control. At present, to our knowledge, no clear association between Down syndrome, Bladder Bowel Dysfunction and neural tube defects has been previously described.

CASE PRESENTATION

We describe two female patients with Down syndrome presenting Bladder Bowel Dysfunction in association with neural tube defects, who both underwent personalized multidisciplinary intervention and pelvic floor rehabilitation, with good clinical outcomes.

CONCLUSION

At present, no screening program has been established in order to rule out neural tube defects or neurogenic urinary anomalies in Down syndrome patients presenting bowel and/or bladder dysfunction. In our opinion, presence of spinal abnormalities, despite rare, may be contribute to urinary symptoms and should be ruled out in patients presenting progressive or persistent Bladder Bowel Dysfunction. Early diagnosis and management of spinal cord defects associated with neurogenic urinary dysfunction may allow to prevent possible complications.

The effectiveness of dance movement therapy for individuals with Down syndrome: a pilot randomised controlled trial

BACKGROUND

Individuals with Down syndrome (DS) exhibit deficits in static and dynamic balance abilities and maladaptive functions. This study aimed to determine the effectiveness of dance movement therapy (DMT) group intervention in individuals with DS.

METHODS

The 31 participating individuals with DS, aged 5-29 years, were randomly divided into intervention (n = 16) and control (n = 15) groups. Posturography was used for static balance measurement, timed up and go test for dynamic balance measurement and the Achenbach System of Empirically Based Assessment (ASEBA) questionnaire for adaptive function and behavioural problem measurement in participants before and after the DMT interventions. The intervention group underwent 60-min DMT intervention once a week for 10 times, while the control group had usual daily activities.

RESULTS

The results revealed a statistically significant difference and large effect sizes in dynamic balance [(f(1, 29) = 4.52, P = 0.04, η_p   ² = 0.14)] in the intervention group compared with the control group. There were no statistically significant differences in static balance and ASEBA scores between the groups.

CONCLUSIONS

This study found that the DMT interventions helped to improve the dynamic balance in individuals with DS.

Insights into the malfunctioning of the mitochondrial citrate carrier: Implications for cell pathology

The mitochondrial citrate carrier (CIC) is a member of the mitochondrial carrier family and is responsible for the transit of tricarboxylates and dicarboxylates across the inner membrane. By modulating the flux of these molecules, it represents the molecular link between catabolic and anabolic reactions that take place in distinct cellular sub-compartments. Therefore, this transport protein represents an important element of investigation both in physiology and in pathology. In this review we critically analyze the involvement of the mitochondrial CIC in several human pathologies, which can be divided into two subgroups, one characterized by a decrease and the other by an increase in the flux of citrate across the inner mitochondrial membrane. In particular, a decrease in the activity of the mitochondrial CIC is responsible for several congenital diseases of different severity, which are also characterized by the increase in urinary levels of L-2- and D-2-hydroxyglutaric acids. On the other hand, an increase in the activity of the mitochondrial CIC is involved, in various ways, in the onset of inflammation, autoimmune diseases, and cancer. Then, understanding the role of CIC and the mechanisms driving the flux of metabolic intermediates between mitochondria and cytosol would potentially allow for manipulation and control of metabolism in pathological conditions.

Anticipatory postural adjustments and kinematic analysis of step ascent and descent in adults with Down syndrome

BACKGROUND

Step ascent and descent is one of the most common daily tasks. Although it is generally considered a rather simple movement, it may not be so easy for participants with Down syndrome.

METHODS

A kinematic analysis of step ascent and descent was conducted, and a comparison between 11 adult participants with Down syndrome and 23 healthy participants was carried out. This analysis was accompanied by a posturographic analysis with the aim of evaluating aspects relating to balance. The principal aim of postural control was to investigate the trajectory of the centre of pressure, while the kinematic analysis of movement included the following: (1) the analysis of anticipatory postural adjustments, (2) the calculation of spatiotemporal parameters and (3) the evaluation of articular range of motion.

RESULTS

A general instability for participants with Down syndrome, highlighted in the postural control by an increased anteroposterior and mediolateral excursion, when the test was conducted with both open and closed eyes, was found out. Regarding anticipatory postural adjustments, this deficit in balance control was revealed by the execution of small steps before completing the movement and by a much longer preparation time anticipating the movement. In addition, the kinematic analysis reported a longer ascent and descent time and a lower velocity, accompanied by a greater rising of both limbs in ascent, which indicates an increased perception of the obstacle. Finally, a wider trunk range of motion in both the sagittal and frontal planes was revealed.

CONCLUSIONS

All the data confirm a compromised balance control that could be associated with damage to the sensorimotor centre.

Biochemical Screening for Fetal Trisomy 21: Pathophysiology of Maternal Serum Markers and Involvement of the Placenta

It is now well established that maternal serum markers are often abnormal in fetal trisomy 21. Their determination is recommended for prenatal screening and pregnancy follow-up. However, mechanisms leading to abnormal maternal serum levels of such markers are still debated. Our objective was to help clinicians and scientists unravel the pathophysiology of these markers via a review of the main studies published in this field, both in vivo and in vitro, focusing on the six most widely used markers (hCG, its free subunit hCGβ, PAPP-A, AFP, uE3, and inhibin A) as well as cell-free feto-placental DNA. Analysis of the literature shows that mechanisms underlying each marker's regulation are multiple and not necessarily directly linked with the supernumerary chromosome 21. The crucial involvement of the placenta is also highlighted, which could be defective in one or several of its functions (turnover and apoptosis, endocrine production, and feto-maternal exchanges and transfer). These defects were neither constant nor specific for trisomy 21, and might be more or less pronounced, reflecting a high variability in placental immaturity and alteration. This explains why maternal serum markers can lack both specificity and sensitivity, and are thus restricted to screening.

Long-Term Outcomes After External Maxillary Distraction Surgery in Patients With Down Syndrome

BACKGROUND

Patients with Down syndrome have severe facial deformities that can precipitate functional consequences and social stigmatization. Craniofacial surgical intervention can play a role in improving these symptoms and patient quality of life. The objective of this study was to investigate the long-term outcomes of distraction osteogenesis and orthognathic surgical intervention in patients with Down syndrome.

MATERIALS AND METHODS

Charts of 3 patients with Down syndrome who were treated with external maxillary distraction osteogenesis were retrospectively reviewed. The patients' caregivers were prospectively interviewed between 10 and 15 years after surgery to determine surgical stability, long-term function, and quality of life status.

RESULTS

All patients and their caregivers reported excellent results with improvements in function and quality of life. Facial skeletal changes have been stable over time. The cephalometric analysis demonstrated significant maxillary advancement in all 3 patients and mandibular changes to correct mandibular prognathism and asymmetry in the patient who underwent finishing orthognathic surgery.

CONCLUSIONS

External maxillary distraction osteogenesis and orthognathic surgery may be considered in select patients with Down syndrome as part of their multidisciplinary health care. These interventions can result in long-term improvements in patient function and quality of life.

Rare copy number variation analysis identifies disease-related variants in atrioventricular septal defect patients

Atrioventricular septal defect (AVSD) is a deleterious subtype of congenital heart diseases (CHD) characterized by atrioventricular canal defect. The pathogenic genetic changes of AVSD remain elusive, particularly for copy number variation (CNV), a large segment variation of the genome, which is one of the major forms of genetic variants resulting in congenital heart diseases. In the present study, we recruited 150 AVSD cases and 100 healthy subjects as controls for whole exome sequencing (WES). We identified total 4255 rare CNVs using exon Hidden Markov model (XHMM) and screened rare CNVs by eliminating common CNVs based on controls and Database of Genomic Variants (DGV). Each patient contained at least 9 CNVs, and the CNV burden was prominently presented in chromosomes 19,22,21&16. Small CNVs (<500 kb) were frequently observed. By leveraging gene-based burden test, we further identified 20 candidate AVSD-risk genes. Among them, DYRK1A, OBSCN and TTN were presented in the core disease network of CHD and highly and dynamically expressed in the heart during the development, which indicated they possessed the high potency to be AVSD-susceptible genes. These findings not only provided a roadmap for finally unveiling the genetic cause of AVSD, but also provided more resources and proofs for clinical genetics.

The Conserved Transcriptional Activation Activity Identified in Dual-Specificity Tyrosine-(Y)-Phosphorylation-Regulated Kinase 1

Dual-specificity tyrosine-(Y)-phosphorylation-regulated kinase 1 (DYRK1) encodes a conserved protein kinase that is indispensable to neuron development. However, whether DYRK1 possesses additional functions apart from kinase function remains poorly understood. In this study, we firstly demonstrated that the C-terminal of ascidian Ciona robusta DYRK1 (CrDYRK1) showed transcriptional activation activity independent of its kinase function. The transcriptional activation activity of CrDYRK1 could be autoinhibited by a repression domain in the N-terminal. More excitingly, both activation and repression domains were retained in HsDYRK1A in humans. The genes, activated by the activation domain of HsDYRK1A, are mainly involved in ion transport and neuroactive ligand-receptor interaction. We further found that numerous mutation sites relevant to the DYRK1A-related intellectual disability syndrome locate in the C-terminal of HsDYRK1A. Then, we identified several specific DNA motifs in the transcriptional regulation region of those activated genes. Taken together, we identified a conserved transcription activation domain in DYRK1 in urochordates and vertebrates. The activation is independent of the kinase activity of DYRK1 and can be repressed by its own N-terminal. Transcriptome and mutation data indicate that the transcriptional activation ability of HsDYRK1A is potentially involved in synaptic transmission and neuronal function related to the intellectual disability syndrome.

The Amount of Light to Vigorous Physical Activity (Met's-Hours/Day) in Children with and without Down Syndrome Attending Elementary School in Japan

Children with Down syndrome (DS) have physical characteristics such as hypotonus of the musculature. Therefore, their attainment rate of physical activity guidelines is low, and guidelines alone may not be sufficient in assessing the amount of physical activity in children with DS. Compared with normal children (NC) of the same grade, light physical activity (LPA) must be considered while assessing physical activity of children with DS, owing to muscle hypotonia. This study included 69 children with DS and 68 NC in grades 4−6 attending elementary school in Japan. The measurements for physical characteristics included age, height, weight, and body mass index. Physical activity was measured using a triaxial accelerometer, which indicated physical activity volume. Children with DS had less moderate-to-vigorous physical activity duration (DS: 53.1 min/day, NC: 65.0 min/day; p < 0.001) but significantly longer LPA duration (DS: 376.4 min/day, NC: 287.7 min/day; p < 0.001) than NC. Conversely, the amount of light to vigorous physical activity (Met’s-hours/day) was greater in children with DS (DS: 16.0 Met’s-hours/day, NC: 14.4 Met’s-hours/day; p = 0.037). In children with DS with muscular hypotonia, vigorous physical activity is challenging, but LPA is feasible. Developing and validating educational programs that promote physical activity with intensity level depending on individual’s physical characteristic are warranted.

Quality of Life Among Down Syndrome Patients With and Without Congenital Heart Disease at King Abdulaziz University Hospital, Jeddah, Saudi Arabia

Background Congenital heart diseases (CHD) are common in Down syndrome patients who will often have additional anomalies, in which the presence of them and their management are expected to impact their quality of life (QoL). There are limited studies trying to evaluate the impact of CHD on the QoL in children with Down syndrome. Methods The present study comprised 97 Down syndrome children. The children's parents responded to phone interviews filling out TNO-AZL (Netherlands Organisation for Applied Scientific Research Academic Medical Centre) Preschool Quality of Life (TAPQOL) and TNO-AZL Child Quality of Life Parent Form (TACQOL-PF) questionnaires. Children were divided into two groups according to their age: group A (one to five years) and group B (six to 15 years). The results were analyzed using Statistical Package for Social Sciences (SPSS) software, version 21 (IBM Corp., Armonk, NY). Results CHD negatively affected motor skills in younger but not older children. All other QoL-related parameters were unaffected by CHD. Conclusion Down syndrome children with CHD demonstrated similar QoL to Down syndrome children without CHD, with the exception of having a lower motor outcome as infants/toddlers. This difference improved with time and did not exist in older children.

Long-term bumetanide administration altered behavioral pattern in mosaic Down's Syndrome: A case report

The behavioral phenotypes emerge from cognitive architecture comprising attention, executive functions, and primary communication skills that all have shown remarkable deficits in Down's Syndrome (DS). These states arise from the proper functional interactions of the contributing neurotransmission and neuromodulation systems and other coding platforms. Gamma-aminobutyric acid (GABA) is an integral part of the neural interaction and regulation networks that its reverse action leads to broad detrimental consequences. This inhibitory substance needs an appropriate balance of co-transporters that largely shape the ionic milieu. Bumetanide, a specific NKCC1 inhibitor used for an eighteen-month interval, showed promising effects in restoring some behavior deficits in a fourteen-year-old boy diagnosed with genetically confirmed mosaic Down's Syndrome.

Fundamental motor skill proficiency among 7- to 10-year-old children with Down syndrome

[Purpose] The purposes of this study were to assess the fundamental motor skill (FMS) of children with Down syndrome (DS) and to compare their FMS proficiencies to those of chronological age-matched and gender-matched typically developing children (TDC). [Participants and Methods] This cross-sectional study involved a total of 60 participants (30 children with DS and 30 TDC). The FMS proficiency of participants was assessed by using the test of gross motor development, second edition (TGMD-2). The data were analyzed using independent samples t-tests to verify the differences between the two groups and gender. The effect size of Cohen's d was also determined for comparing the two groups. [Results] The results showed that there were significant differences between children with DS and the TDC on locomotor and object control standard scores, and the gross motor quotient (GMQ). However, there were no significant gender-based differences in the locomotor and object control standard scores and the GMQ in both groups. [Conclusion] Based on the current results, the FMS proficiency of children with DS is lower than the TDC. Therefore, a therapeutic intervention program is necessary for children with DS to improve their FMS proficiency.

Impact of COVID-19 on physical and mental functioning in adolescents with disabilities in a sports nongovernmental organization

Abstract Objective: This study aimed to assess physical and mental health, and health-related quality of life (HRQL) parameters in adolescents with physical disabilities enrolled in a sports nongovernmental organization (NGO) versus adolescents without disabilities during coronavirus disease 2019 (COVID-19) pandemic. Methods: This cross-sectional study included 30 adolescents with disabilities and 86 adolescents without disabilities who responded to an online questionnaire with sociodemographic data and self-rated healthcare routine information during the COVID-19 quarantine. Validated self-report versions of the Strengths and Difficulties Questionnaire (SDQ), Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0), Pittsburgh Sleep Quality Index (PSQI), and Pediatric Outcome Data Collection Instrument (PODCI) were also applied. Results: The median of emotional [4 (0–10) vs. 5 (0–10), p=0.018] and prosocial [7 (0–10) vs. 9 (3–10), p=0.006] problems was lower in adolescents with disabilities versus adolescents without disabilities. Adolescents with disabilities had significantly lower global function [68 (21–99) vs. 94 (67–100), p<0.001] and higher happiness scores in the PODCI scale [90 (65–100) vs. 80 (0–100), p=0.016] compared to controls. Logistic regression analysis demonstrated that physical activity/week (OR=1.03; 95%CI 1.01–1.05, p=0.002) was higher in adolescents with disabilities compared to adolescents without disabilities. However, housework activities (OR=0.14; 95%CI 0.04–0.43, p=0.001) and screen time ≥3 h/day (OR=0.09; 95%CI 0.02–0.38, p=0.001) were lower in adolescents with disabilities compared to adolescents without disabilities. Conclusion: Adolescents with disabilities attending a sports NGO were not at higher risk of adverse health-related indicators; despite showing reduced physical function, they reported more physical activity, higher happiness, and less screen time compared to adolescents without disabilities during the COVID-19 pandemic.

Re-examine the influence of organizational identification on unethical pro-supervisor behavior

Employees' unethical pro-supervisor behavior (UPSB) is common in organizations. Existing research primarily argued that organizational identification increases this behavior, emphasizing that UPSB benefits organizations indirectly. However, it ignores that UPSB can sometimes serve the interests of the supervisor at the expense of the interests of the organization. Drawing on social identity theory and social cognitive theory, this study aims to emphasize this point by proposing that organizational identification can inhibit employees' UPSB via the mediation of felt obligation. We also propose that perceived organizational cronyism would weaken the negative effect. Data were collected through a self-reported online questionnaire based on a three-wave research design and analyzed through hierarchical regression analyses. With a sample of 578 Chinese employees, we found support for our propositions. Implications and limitations are discussed.

Partial trisomy 21 with or without highly restricted Down syndrome critical region (HR-DSCR): report of two new cases and reanalysis of the genotype-phenotype association

BACKGROUND

Down syndrome (DS) is caused by the presence of an extra copy of full or partial human chromosome 21 (Hsa21). Partial (segmental) trisomy 21 (PT21) is the duplication of only a delimited region of Hsa21 and can be associated or not to DS: the study of PT21 cases is an invaluable model for addressing genotype-phenotype correlation in DS. Previous works reported systematic reanalyses of 132 subjects with PT21 and allowed the identification of a 34-kb highly restricted DS critical region (HR-DSCR) as the minimal region whose duplication is shared by all PT21 subjects diagnosed with DS.

METHODS

We report clinical data and cytogenetic analysis of two children with PT21, one with DS and the other without DS. Moreover, we performed a systematic bibliographic search for any new PT21 report.

RESULTS

Clinical and cytogenetic analyses of the two PT21 children have been reported: in Case 1 the duplication involves the whole long arm of Hsa21, except for the last 2.7 Mb, which are deleted as a consequence of an isodicentric 21: the HR-DSCR is within the duplicated regions and the child is diagnosed with DS. In Case 2 the duplication involves 7.1 Mb of distal 21q22, with a deletion of 2.1 Mb of proximal 20p, as a consequence of an unbalanced translocation: the HR-DSCR is not duplicated and the child presents with psychomotor development delay but no clinical signs of DS. Furthermore, two PT21 reports recently published (named Case 3 and 4) have been discussed: Case 3 has DS diagnosis, nearly full trisomy for Hsa21 and a monosomy for the 21q22.3 region. Case 4 is a baby without DS and a 0.56-Mb duplication of 21q22.3. Genotype-phenotype correlation confirmed the presence of three copies of the HR-DSCR in all DS subjects and two copies in all non-DS individuals.

CONCLUSIONS

The results presented here are fully consistent with the hypothesis that the HR-DSCR is critically associated with DS diagnosis. No exception to this pathogenetic model was found. Further studies are needed to detect genetic determinants likely located in the HR-DSCR and possibly responsible for core DS features, in particular intellectual disability.

Pediatric Population with Down Syndrome: Obesity and the Risk of Cardiovascular Disease and Their Assessment Using Omics Techniques-Review

People with Down syndrome (PWDS) are more at risk for developing obesity, oxidative stress disorders, metabolic disorders, and lipid and carbohydrate profile disorders than the general population. The presence of an additional copy of genes on chromosome 21 (i.e., the superoxide dismutase 1 gene (SOD1) and gene coding for the cystathionine β-synthase (CBS) enzyme) raises the risk for cardiovascular disease (CVD). As a result of disorders in metabolic processes and biochemical pathways, theoretically protective factors (low homocysteine level, high SOD1 level) do not fulfil their original functions. Overexpression of the CBS gene leads to the accumulation of homocysteine-a CVD risk factor. An excessive amount of protective SOD1, in the case of a lack of compensatory increase in the activity of catalase and peroxidase, leads to intensifying free radical processes. The occurrence of metabolic disorders and the amplified effect of oxidative stress carries higher risk of exposure of people with DS to CVD. At present, classic predispositions are known, but it is necessary to identify early risk factors in order to be able to employ CVD and obesity prophylaxis. Detailed determination of the metabolic and lipid profile may provide insight into the molecular mechanisms underlying CVD.

Migration deficits of the neural crest caused by CXADR triplication in a human Down syndrome stem cell model

Down syndrome (DS) is the most common chromosomal abnormality in live-born infants and is caused by trisomy of chromosome 21. Most individuals with DS display craniofacial dysmorphology, including reduced sizes of the skull, maxilla, and mandible. However, the underlying pathogenesis remains largely unknown. Since the craniofacial skeleton is mainly formed by the neural crest, whether neural crest developmental defects are involved in the craniofacial anomalies of individuals with DS needs to be investigated. Here, we successfully derived DS-specific human induced pluripotent stem cells (hiPSCs) using a Sendai virus vector. When DS-hiPSCs were induced to differentiate into the neural crest, we found that trisomy 21 (T21) did not influence cell proliferation or apoptosis. However, the migratory ability of differentiated cells was significantly compromised, thus resulting in a substantially lower number of postmigratory cranial neural crest stem cells (NCSCs) in the DS group than in the control group. We further discovered that the migration defects could be partially attributed to the triplication of the coxsackievirus and adenovirus receptor gene (CXADR; an adhesion protein) in the DS group cells, since knockdown of CXADR substantially recovered the cell migratory ability and generation of postmigratory NCSCs in the DS group. Thus, the migratory deficits of neural crest cells may be an underlying cause of craniofacial dysmorphology in individuals with DS, which may suggest potential targets for therapeutic intervention to ameliorate craniofacial or other neural crest-related anomalies in DS.

Comprehensive cardiopulmonary profile of individuals with Down syndrome

BACKGROUND

Individuals with Down syndrome (DS) have low levels of cardiorespiratory fitness and previous studies have shown that these low levels of fitness have a physiological cause. During exercise, the cardiovascular, ventilatory and muscular systems are simultaneously active. While individual parameters of these systems have been investigated in DS before, the interaction between these parameters and systems have not been discussed in detail. Doing so may provide important insight regarding the aetiology of low cardiorespiratory fitness and which parameters of the cardiovascular, pulmonary and muscular systems are altered in individuals with DS compared with their peers without DS.

METHODS

Cardiopulmonary exercise tests were performed in healthy adults with and without DS. Parameters related to the cardiovascular, ventilatory and muscular systems were collected until VO_2peak . In total, 51 participants were included in analysis, of which 21 had DS.

RESULTS

Individuals with DS showed lower peak values for all collected outcomes (P ≤ 0.001) compared with those without DS, except for ventilatory threshold as a percentage of maximal oxygen uptake and V_E /VCO₂ slope, which were similar.

CONCLUSIONS

Our results show that individuals with DS present impairments across the cardiovascular, ventilatory and muscular aspects of the cardiopulmonary system.

Field-based versus laboratory-based estimates of muscle quality index in adolescents with and without Down syndrome

BACKGROUND

Low muscle quality index (MQI) is a potential risk of developing functional impairments in older people. However, considering that individuals with Down syndrome (DS) present with a faster decline in biological aging, an investigation on MQI in individuals with DS is necessary. The aims of this present cross-sectional study were to compare (1) MQI between adolescents with and without DS and (2) evaluate laboratory versus field-based estimates of MQI.

METHODS

Fifty-six adolescents were recruited and separated into two groups: DS (n = 30, 13 boys and 17 girls; age: 12.38 ± 3.07 years) and a control (non-DS; n = 26, 9 boys and 17 girls; age: 12.46 ± 2.88 years). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy X-ray absorptiometry (DXA). Field-based MQI was quantified from the ratio of hand grip strength (HGS) to body mass index (BMI). For statistical analyses, a two-way ANOVA was conducted for group comparisons, and a Pearson correlation was used to test the association between field MQI and laboratory MQI.

RESULTS

Adolescents with DS displayed lower field (P = 0.001), laboratory MQI estimates (P = 0.001) and HGS (P = 0.001) as compared non-DS. Also, there was a strong correlation effect between field MQI and laboratory MQI estimates (P < 0.001, R = 0.81).

CONCLUSION

Adolescents with DS have lower field and laboratory MQI compared with adolescents without DS. Simpler field MQI might be used in daily clinical practice, with special attention to those with DS.

Effects of 24-week basketball programme on body composition and functional fitness on adults with Down syndrome

BACKGROUND

The body index [body mass, body mass index (BMI), waist circumference and waist-height ratio] and functional fitness (aerobic capacity, muscular strength, balance, flexibility and functional ability) of people with Down syndrome (DS) are substantially lower than those in the general population, as DS has an overall negative impact on health.

AIMS

This study explored the effect of a 24-week basketball training programme on the body composition and functional fitness of adults with DS.

METHODS AND PROCEDURE OUTCOMES

Twenty-two adults with DS (24 ± 6 years; 25 ± 4 kg/m² ) were randomly allocated to the experimental (n = 11, 67.04 kg) and control groups (n = 11, 69.36 kg). The experimental group performed 24 weeks of basketball programme training (3 times per week, 60 min per session), while the control group maintained their daily activities without any special physical training. Body composition and functional fitness parameters were measured before and after the intervention. To evaluate the differences between groups, an analysis of covariance (ANCOVA) was used while controlling for differences at baseline.

RESULTS

Hip circumference and waist-height ratio were statistically different at baseline between the intervention and control groups. After the 24-week basketball training programme, the results showed significant differences between the exercise and control groups for hip circumference, body mass, BMI, waist circumference, hip circumference, waist-height ratio, flexibility, aerobic capacity, static and dynamic balance, balance and basketball functional ability (P < 0.05). The exercise group showed significant improvements in all variables of body composition and functional fitness (P < 0.05) except for the waist-hip ratio. There was no statistical significance between all physical composition and functional health variables in the control group except for the standing long jump (P > 0.05), with effect sizes ranging from small to large.

CONCLUSIONS AND IMPLICATIONS

The basketball training programme improved body composition and functional fitness of adults with DS.

Inspiratory Muscle Training and Physical Fitness in Children With Down Syndrome: A Randomized Controlled Trial

OBJECTIVE

To investigate the effect of inspiratory muscle training (IMT) on physical fitness in children with Down syndrome (DS).

DESIGN

Randomized control trial.

SETTING

The study was conducted in a private physical therapy center.

PARTICIPANTS

Forty boys and girls with DS aged between 7 and 10 years were enrolled in this study (N=40). They were randomly and equally divided into 2 groups (A and B).

INTERVENTIONS

All participants received 30 minutes of aerobic exercise training 3 times per week for 12 weeks, whereas group B received an additional 30 minutes of IMT before each aerobic exercise session.

MAIN OUTCOMES MEASURES

Maximal inspiratory pressure (MIP); maximal expiratory pressure (MEP); submaximal aerobic endurance; muscular strength; endurance.

RESULTS

Among the group undergoing IMT, there were significant improvements in MIP, MEP, and submaximal aerobic endurance using the six-minute walk test (6MWT); strength and endurance using the curl-up, dumbbell press, trunk lift, standing long jump, seated push-up, pull-up, and flexed-arm hang; and back saver sit and reach tests (P > 0.05).

CONCLUSIONS

Inspiratory muscle training and aerobic exercise training demonstrated more significant improvements in physical fitness than in those children who received only aerobic exercise training.