Corrigendum to "Polysaccharide and ethanol extracts of Anoectochilus formosanus Hayata: Antioxidant, wound-healing, antibacterial, and cytotoxic activities".

[This corrects the article DOI: 10.1016/j.heliyon.2023.e13559.].

Efficient generation of a self-organizing neuromuscular junction model from human pluripotent stem cells.

The complex neuromuscular network that controls body movements is the target of severe diseases that result in paralysis and death. Here, we report the development of a robust and efficient self-organizing neuromuscular junction (soNMJ) model from human pluripotent stem cells that can be maintained long-term in simple adherent conditions. The timely application of specific patterning signals instructs the simultaneous development and differentiation of position-specific brachial spinal neurons, skeletal muscles, and terminal Schwann cells. High-content imaging reveals self-organized bundles of aligned muscle fibers surrounded by innervating motor neurons that form functional neuromuscular junctions. Optogenetic activation and pharmacological interventions show that the spinal neurons actively instruct the synchronous skeletal muscle contraction. The generation of a soNMJ model from spinal muscular atrophy patient-specific iPSCs reveals that the number of NMJs and muscle contraction is severely affected, resembling the patient's pathology. In the future, the soNMJ model could be used for high-throughput studies in disease modeling and drug development. Thus, this model will allow us to address unmet needs in the neuromuscular disease field.

Excision of a Protein-Derived Amine for p-Aminobenzoate Assembly by the Self-Sacrificial Heterobimetallic Protein CADD.

Chlamydia protein associating with death domains (CADD), the founding member of a recently discovered class of nonheme dimetal enzymes termed hemeoxygenase-like dimetaloxidases (HDOs), plays an indispensable role in pathogen survival. CADD orchestrates the biosynthesis of p-aminobenzoic acid (pABA) for integration into folate via the self-sacrificial excision of a protein-derived tyrosine (Tyr27) and several additional processing steps, the nature and timing of which have yet to be fully clarified. Nuclear magnetic resonance (NMR) and proteomics approaches reveal the source and probable timing of amine installation by a neighboring lysine (Lys152). Turnover studies using limiting O2 have identified a para-aminobenzaldehyde (pABCHO) metabolic intermediate that is formed on the path to pABA formation. The use of pABCHO and other probe substrates shows that the heterobimetallic Fe/Mn form of the enzyme is capable of oxygen insertion to generate the pABA-carboxylate.

Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial.

BACKGROUND AND OBJECTIVES: Primary mitochondrial myopathies (PMMs) encompass a group of genetic disorders that impair mitochondrial oxidative phosphorylation, adversely affecting physical function, exercise capacity, and quality of life (QoL). Current PMM standards of care address symptoms, with limited clinical impact, constituting a significant therapeutic unmet need. We present data from MMPOWER-3, a pivotal, phase-3, randomized, double-blind, placebo-controlled clinical trial that evaluated the efficacy and safety of elamipretide in participants with genetically confirmed PMM. METHODS: After screening, eligible participants were randomized 1:1 to receive either 24 weeks of elamipretide at a dose of 40 mg/d or placebo subcutaneously. Primary efficacy endpoints included change from baseline to week 24 on the distance walked on the 6-minute walk test (6MWT) and total fatigue on the Primary Mitochondrial Myopathy Symptom Assessment (PMMSA). Secondary endpoints included most bothersome symptom score on the PMMSA, NeuroQoL Fatigue Short-Form scores, and the patient global impression and clinician global impression of PMM symptoms. RESULTS: Participants (N = 218) were randomized (n = 109 elamipretide; n = 109 placebo). The m0ean age was 45.6 years (64% women; 94% White). Most of the participants (n = 162 [74%]) had mitochondrial DNA (mtDNA) alteration, with the remainder having nuclear DNA (nDNA) defects. At screening, the most frequent bothersome PMM symptom on the PMMSA was tiredness during activities (28.9%). At baseline, the mean distance walked on the 6MWT was 336.7 ± 81.2 meters, the mean score for total fatigue on the PMMSA was 10.6 ± 2.5, and the mean T score for the Neuro-QoL Fatigue Short-Form was 54.7 ± 7.5. The study did not meet its primary endpoints assessing changes in the 6MWT and PMMSA total fatigue score (TFS). Between the participants receiving elamipretide and those receiving placebo, the difference in the least squares mean (SE) from baseline to week 24 on distance walked on the 6MWT was -3.2 (95% CI -18.7 to 12.3; p = 0.69) meters, and on the PMMSA, the total fatigue score was -0.07 (95% CI -0.10 to 0.26; p = 0.37). Elamipretide treatment was well-tolerated with most adverse events being mild to moderate in severity. DISCUSSION: Subcutaneous elamipretide treatment did not improve outcomes in the 6MWT and PMMSA TFS in patients with PMM. However, this phase-3 study demonstrated that subcutaneous elamipretide is well-tolerated. TRIAL REGISTRATION INFORMATION: Trial registered with clinicaltrials.gov, Clinical Trials Identifier: NCT03323749; submitted on October 12, 2017; first patient enrolled October 9, 2017. CLINICALTRIALS: gov/ct2/show/NCT03323749?term = elamipretide&draw = 2&rank = 9. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that elamipretide does not improve the 6MWT or fatigue at 24 weeks compared with placebo in patients with primary mitochondrial myopathy.

Pamrevlumab, a Fully Human Monoclonal Antibody Targeting Connective Tissue Growth Factor, for Non-Ambulatory Patients with Duchenne Muscular Dystrophy.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a neuromuscular disease stemming from dystrophin gene mutations. Lack of dystrophin leads to progressive muscle damage and replacement of muscle with fibrotic and adipose tissue. Pamrevlumab (FG-3019), a fully human monoclonal antibody that binds to connective tissue growth factor (CTGF), is in Phase III development for treatment of DMD and other diseases. METHODS: MISSION (Study 079; NCT02606136) was an open-label, Phase II, single-arm trial of pamrevlumab in 21 non-ambulatory patients with DMD (aged≥12 years, receiving corticosteroids) who received 35-mg/kg intravenous infusions every 2 weeks for 2 years. The primary endpoint was change from baseline in percent predicted forced vital capacity (ppFVC). Secondary endpoints included other pulmonary function tests, upper limb function and strength assessments, and changes in upper arm fat and fibrosis scores on magnetic resonance imaging. RESULTS: Fifteen patients completed the trial. Annual change from baseline (SE) in ppFVC was -4.2 (0.7) (95% CI -5.5, -2.8). Rate of decline in ppFVC in pamrevlumab-treated patients was slower than observed in historical published trials of non-ambulatory patients. MISSION participants experienced slower-than-anticipated muscle function declines compared with natural history and historical published trials of non-ambulatory patients with DMD. Pamrevlumab was well-tolerated. Treatment-emergent adverse events were mild to moderate, and none led to study discontinuation. CONCLUSIONS: nti-CTGF therapy with pamrevlumab represents a potential treatment for DMD. The lack of internal control group limits the results.

Polysaccharide and ethanol extracts of Anoectochilus formosanus Hayata: Antioxidant, wound-healing, antibacterial, and cytotoxic activities.

Introduction: Polysaccharide and alcohol extracts of Anoectochilus formosanus Hayata have attracted great attention as they exhibit noteworthy properties such as prebiotic and anti-hyperglycemic effects. However, the antioxidant and wound-healing activities of the polysaccharide extract as well as the antibacterial and cytotoxic effects of the ethanol extracts have not been thoroughly uncovered. Therefore, our study investigated these bioactivities of the two extracts prepared from Anoectochilus formosanus to broaden understandings of medical benefits of the plant. Methods: The monosaccharide composition was analyzed by HPAEC-PAD. The antioxidant and wound-healing activities of the polysaccharide extract were evaluated by ABTS and scratch assays, respectively. The broth dilution method was used to determine the antibacterial ability of the ethanol extract. Additionally, the cytotoxic and mechanistic effects of this extract against hepatocellular carcinoma HUH-7 cells was assessed by MTT assay, qRT-PCR and Western blotting methods. Results: The polysaccharide extract possessed an effective free radical scavenging ability in an ABTS assay (IC50 = 44.92 µg/ml). The extract also ameliorated wound recovery in a fibroblast scratch assay. Meanwhile, the ethanol extract was able to inhibit the growth of Staphylococcus aureus (MIC = 2500 µg/ml), Bacillus cereus (MIC = 2500 µg/ml), Escherichia coli (MIC = 2500 µg/ml), and Pseudomonas aeruginosa (MIC = 1250 µg/ml). Additionally, it repressed the viability of HUH-7 cells (IC50 = 53.44 µg/ml), possibly through upregulating the expression of caspase 3 (CASP3), CASP8, and CASP9 at both mRNA and protein levels. Conclusion: The polysaccharide extract of A. formosanus exhibited the antioxidant and wound-healing properties whereas the ethanol extract showed the antibacterial activity and cytotoxicity against HUH-7 cells. These findings specify notable biological effects of the two extracts which could be of potential use in human healthcare.

Multi-Laboratory Evaluation of Prototype Dried Blood Spot Quality Control Materials for Creatine Kinase-MM Newborn Screening Assays.

Pilot studies to detect newborns with Duchenne Muscular Dystrophy (DMD) by newborn bloodspot screening (NBS) have been conducted under the New York State Newborn Screening Program (NYS) and are currently in progress as part of the Early Check Program at Research Triangle Institute (RTI) International. The Newborn Screening Quality Assurance Program (NSQAP) at the U.S. Centers for Disease Control and Prevention (CDC) produced a set of seven prototype dried blood spot (DBS) reference materials spiked with varying levels of creatine kinase MM isoform (CK-MM). These DBS were evaluated over a 3-week period by CDC, NYS, and RTI, all using the same CK-MM isoform-specific fluoroimmunoassay. Results from each laboratory were highly correlated with the relative proportion of CK-MM added to each of the six spiked pools. Based on reference ranges established by NYS and RTI for their pilot studies, these contrived DBS collectively spanned the CK-MM ranges found in typical newborns and the elevated ranges associated with DMD. This set allows quality assessment over the wide range of fluctuating CK-MM levels in typical and DMD-affected newborns.

Seroprevalence of Adeno-Associated Virus Neutralizing Antibodies in Males with Duchenne Muscular Dystrophy.

Adeno-associated virus (AAV)-based gene therapies are emerging strategies in Duchenne muscular dystrophy (DMD) treatment. Exposure to wild-type AAV can lead to development of neutralizing antibodies (NAbs) and blocking of AAV transduction, thereby limiting the delivery of AAV vector-based gene therapy. Therefore, it is imperative to check for the presence of AAV NAbs in a patient who is a candidate for gene therapy. We prospectively enrolled 101 genetically confirmed males with DMD (median age 11 years, 48% ambulatory and 59% on steroids) and performed AAV neutralization assays against AAV2, AAV8, AAV9, and AAVrh74 serotypes. The serotype analysis showed that AAV9 (36%) and AAVrh74 (32%) seroprevalence was lower compared with AAV2 (56%) and AAV8 (47%). Interestingly, age was not correlated with NAb titer for any of the capsids. NAb responses were observed at a higher frequency in African American participants and at a lower frequency in Caucasian participants for all four serotypes. Further analysis showed no significant differences in NAb titers regardless of serotype and whether participants were taking steroids or not. Finally, we observed higher AAV8, AAV9, and AAVrh74 seroprevalence and significantly higher AAV2 and AAV8 NAb titers in participants who were ambulatory compared with nonambulatory participants. Overall, these data identify AAV9 and AAVrh74 as the two serotypes with lower pre-existing NAb titers in this study's cohort of 101 males with DMD, possibly showing their utility in future gene therapy applications in treatment of this cohort of patients with DMD.

Distal Hydrophobic Loop Modulates the Copper Active Site and Reaction of AA13 Polysaccharide Monooxygenases.

Polysaccharide monooxygenases (PMOs) use a type-2 copper center to activate O2 for the selective hydroxylation of one of the two C-H bonds of glycosidic linkages. Our electron paramagnetic resonance (EPR) analysis and molecular dynamics (MD) simulations suggest the unprecedented dynamic roles of the loop containing the residue G89 (G89 loop) on the active site structure and reaction cycle of starch-active PMOs (AA13 PMOs). In the Cu(II) state, the G89 loop could switch between an "open" and "closed" conformation, which is associated with the binding and dissociation of an aqueous ligand in the distal site, respectively. The conformation of the G89 loop influences the positioning of the copper center on the preferred substrate of AA13 PMOs. The dissociation of the distal ligand results in the bending of the T-shaped core of the Cu(II) active site, which could help facilitate its reduction to the active Cu(I) state. In the Cu(I) state, the G89 loop is in the "closed" conformation with a confined copper center, which could allow for efficient O2 binding. In addition, the G89 loop remains in the "closed" conformation in the Cu(II)-superoxo intermediate, which could prevent off-pathway superoxide release via exchange with the distal aqueous ligand. Finally, at the end of the reaction cycle, aqueous ligand binding to the distal site could switch the G89 loop to the "open" conformation and facilitate product release.

Self-sacrificial tyrosine cleavage by an Fe:Mn oxygenase for the biosynthesis of para-aminobenzoate in Chlamydia trachomatis.

Chlamydia protein associating with death domains (CADD) is involved in the biosynthesis of para-aminobenzoate (pABA), an essential component of the folate cofactor that is required for the survival and proliferation of the human pathogen Chlamydia trachomatis. The pathway used by Chlamydiae for pABA synthesis differs from the canonical multi-enzyme pathway used by most bacteria that relies on chorismate as a metabolic precursor. Rather, recent work showed pABA formation by CADD derives from l-tyrosine. As a member of the emerging superfamily of heme oxygenase-like diiron oxidases (HDOs), CADD was proposed to use a diiron cofactor for catalysis. However, we report maximal pABA formation by CADD occurs upon the addition of both iron and manganese, which implicates a heterobimetallic Fe:Mn cluster is the catalytically active form. Isotopic labeling experiments and proteomics studies show that CADD generates pABA from a protein-derived tyrosine (Tyr27), a residue that is ∼14 Šfrom the dimetal site. We propose that this self-sacrificial reaction occurs through O2 activation by a probable Fe:Mn cluster through a radical relay mechanism that connects to the "substrate" Tyr, followed by amination and direct oxygen insertion. These results provide the molecular basis for pABA formation in C. trachomatis, which will inform the design of novel therapeutics.

An expanded access program of risdiplam for patients with Type 1 or 2 spinal muscular atrophy.

OBJECTIVE: The US risdiplam expanded access program (EAP; NCT04256265) was opened to provide individuals with Type 1 or 2 spinal muscular atrophy (SMA) who had no satisfactory treatment options access to risdiplam prior to commercial availability. The program was designed to collect safety data during risdiplam treatment. METHODS: Patients were enrolled from 23 non-preselected sites across 17 states and treated with risdiplam orally once daily. Eligible patients had a 5q autosomal recessive Type 1 or 2 SMA diagnosis, were aged ≥2 months at enrollment, and were ineligible for available and approved SMA treatments or could not continue treatment due to a medical condition, lack/loss of efficacy, or the COVID-19 pandemic. RESULTS: Overall, 155 patients with Type 1 (n = 73; 47.1%) or 2 SMA (n = 82; 52.9%) were enrolled and 149 patients (96.1%) completed the EAP (defined as obtaining access to commercial risdiplam, if desired). The median treatment duration was 4.8 months (range, 0.3-9.2 months). The median patient age was 11 years (range, 0-50 years), and most patients (n = 121; 78%) were previously treated with a disease-modifying therapy. The most frequently reported adverse events were diarrhea (n = 10; 6.5%), pyrexia (n = 7; 4.5%), and upper respiratory tract infection (n = 5; 3.2%). The most frequently reported serious adverse event was pneumonia (n = 3; 1.9%). No deaths were reported. INTERPRETATION: In the EAP, the safety profile of risdiplam was similar to what was reported in pivotal risdiplam clinical trials. These safety data provide further support for the use of risdiplam in the treatment of adult and pediatric patients with SMA.

Evaluation of effects of continued corticosteroid treatment on cardiac and pulmonary function in non-ambulatory males with Duchenne muscular dystrophy from MD STARnet.

INTRODUCTION/AIMS: Corticosteroids have been shown to improve muscle strength and delay loss of ambulation (LOA) in Duchenne muscular dystrophy (DMD) and are considered standard of care despite significant side-effects. The objective of this study is to evaluate whether corticosteroid treatment after LOA is beneficial for cardiac or pulmonary functions among boys with DMD. METHODS: We used the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet) to characterize associations between corticosteroid use and onset of abnormal left ventricular (LV) function or abnormal percent predicted forced vital capacity (ppFVC) among 398 non-ambulatory boys with DMD. Kaplan-Meier curve estimation was used to compare time to onset by corticosteroid use groups; Cox proportional hazards modeling was used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals. RESULTS: We found no differences in time to onset of abnormal LV function by corticosteroid use groups. We observed a longer time from LOA to first abnormal ppFVC in boys that were treated with corticosteroid ≥1 y beyond LOA compared with those with no corticosteroid use or those who stopped corticosteroid use within 1 y of LOA. DISCUSSION: Our findings show no association of corticosteroid use beyond LOA with the onset of abnormal LV function, but a significant association with a delay in onset of abnormal ppFVC. Prospective studies of corticosteroid use in boys with DMD who have lost ambulation may identify benefits and can better elucidate risks, allowing for more effective counseling of patients on continuing treatment after LOA.

A Randomized, Double-Blind, Placebo-Controlled, Global Phase 3 Study of Edasalonexent in Pediatric Patients with Duchenne Muscular Dystrophy: Results of the PolarisDMD Trial.

BACKGROUND: Edasalonexent (CAT-1004) is an orally-administered novel small molecule drug designed to inhibit NF-κB and potentially reduce inflammation and fibrosis to improve muscle function and thereby slow disease progression and muscle decline in Duchenne muscular dystrophy (DMD). OBJECTIVE: This international, randomized 2 : 1, placebo-controlled, phase 3 study in patients ≥4 - < 8 years old with DMD due to any dystrophin mutation examined the effect of edasalonexent (100 mg/kg/day) compared to placebo over 52 weeks. METHODS: Endpoints were changes in the North Star Ambulatory Assessment (NSAA; primary) and timed function tests (TFTs; secondary). Assessment of health-related function used the Pediatric Outcomes Data Collection tool (PODCI). RESULTS: One hundred thirty one patients received edasalonexent (n = 88) and placebo (n = 43). At week 52, differences between edasalonexent and placebo for NSAA total score and TFTs were not statistically significant, although there were consistently less functional declines in the edasalonexent group. A pre-specified analysis by age demonstrated that younger patients (≤6.0 years) showed more robust and statistically significant differences between edasalonexent and placebo for some assessments. Treatment was well-tolerated and the majority of adverse events were mild, and most commonly involved the gastrointestinal system (primarily diarrhea). CONCLUSIONS: Edasalonexent was generally well-tolerated with a manageable safety profile at the dose of 100 mg/kg/day. Although edasalonexent did not achieve statistical significance for improvement in primary and secondary functional endpoints for assessment of DMD, subgroup analysis suggested that edasalonexent may slow disease progression if initiated before 6 years of age. (NCT03703882).

Association of genetic mutations and loss of ambulation in childhood-onset dystrophinopathy.

BACKGROUND: Quantifying associations between genetic mutations and loss of ambulation (LoA) among males diagnosed with childhood-onset dystrophinopathy is important for understanding variation in disease progression and may be useful in clinical trial design. METHODS: Genetic and clinical data from the Muscular Dystrophy Surveillance, Tracking, and Research Network for 358 males born and diagnosed from 1982 to 2011 were analyzed. LoA was defined as the age at which independent ambulation ceased. Genetic mutations were defined by overall type (deletion/duplication/point mutation) and among deletions, those amenable to exon-skipping therapy (exons 8, 20, 44-46, 51-53) and another group. Cox proportional hazards regression modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Mutation type did not predict time to LoA. Controlling for corticosteroids, Exons 8 (HR = 0.22; 95% CI = 0.08, 0.63) and 44 (HR = 0.30; 95% CI = 0.12, 0.78) were associated with delayed LoA compared to other exon deletions. CONCLUSIONS: Delayed LoA in males with mutations amenable to exon-skipping therapy is consistent with previous studies. These findings suggest that clinical trials including exon 8 and 44 skippable males should consider mutation information prior to randomization.

Fine Tuning of the Copper Active Site in Polysaccharide Monooxygenases.

Type 2 copper active sites, one of the several important copper active sites in biology, were recently found in the novel superfamily of polysaccharide monooxygenases (PMOs) that cleave recalcitrant polysaccharides via an unprecedented oxidative mechanism. The copper center in PMOs is ligated by the bidentate N-terminal histidine residue and another conserved histidine residue, forming a unique T-shaped core termed as Histidine brace. This core serves as the foundation for diverse structures and electronic properties among PMO families and subfamilies. Understanding of the copper active site in PMOs is limited to the static solid structures obtained with X-ray diffraction (XRD), whereas in several families, the copper center exists as a mixture of species in solution as indicated by electron paramagnetic resonance (EPR) spectroscopy. To obtain further details on the copper active sites in PMOs, we carried out density functional theory calculations and molecular dynamics simulations on MtPMO3* that were previously studied with XRD, EPR, mutagenesis, and activity assays. The results reveal the fine-tuning of the binding of the distal ligands by both proximal and distal H-bond-forming residues. Q167 forms H bonds with the proximal OTyr ligand of Y167 and the equatorial aqueous ligand (Oeq). T74 forms a H bond with the distal aqueous ligand (Odis). Removing these H bonds by mutating Q167 or T74 to alanine results in great fluctuations of the axial ligands. Strengthening the proximal H bonds by mutating Q167 to glutamate confines Y167 to the copper centers. In all mutants, the residence time of Odis is significantly reduced. Q167A, Q167E, and T74A mutants were previously shown to have a significantly reduced activity. Our results indicate that well-tuned H bonds are required for the activity of PMOs.

Use of a wearable device to assess sleep and motor function in Duchenne muscular dystrophy.

INTRODUCTION: Rest-activity disruption is an important feature of Duchenne muscular dystrophy (DMD). We sought to describe sleep impairment and its relationship to quality of life (QOL) and to evaluate associations between rest-activity, sleep quality, and 6-minute walk test (6MWT) in DMD. METHODS: Sleep impairment and its relationship to QOL was assessed by questionnaire in 54 children (33 ambulatory, 21 nonambulatory) with DMD. Rest-activity characteristics were calculated for 23 of these children (14 ambulatory, nine nonambulatory) by actigraphy. RESULTS: Pathologic sleep was reported in 11 (20%) participants and correlated with lower QOL but not with ambulatory status. In ambulatory participants who completed actigraphy, rest-activity rhythm fragmentation was associated with subjective sleep impairment. Habitual daytime activity level was associated with 6MWT performance. DISCUSSION: Children with DMD experience substantial sleep impairment that is related to QOL. Wrist actigraphy may be a parsimonious tool for monitoring both sleep and motor impairment in ambulatory children with DMD.

The Survival of Motor Neuron Protein Acts as a Molecular Chaperone for mRNP Assembly.

Spinal muscular atrophy (SMA) is a motor neuron disease caused by reduced levels of the survival of motor neuron (SMN) protein. SMN is part of a multiprotein complex that facilitates the assembly of spliceosomal small nuclear ribonucleoproteins (snRNPs). SMN has also been found to associate with mRNA-binding proteins, but the nature of this association was unknown. Here, we have employed a combination of biochemical and advanced imaging methods to demonstrate that SMN promotes the molecular interaction between IMP1 protein and the 3' UTR zipcode region of ß-actin mRNA, leading to assembly of messenger ribonucleoprotein (mRNP) complexes that associate with the cytoskeleton to facilitate trafficking. We have identified defects in mRNP assembly in cells and tissues from SMA disease models and patients that depend on the SMN Tudor domain and explain the observed deficiency in mRNA localization and local translation, providing insight into SMA pathogenesis as a ribonucleoprotein (RNP)-assembly disorder.

Sleep profiles in children with Down syndrome.

Down syndrome (DS) is the most common genetic cause of intellectual disability and results from an extra chromosome 21 (Trisomy 21). Sleep issues and/or obstructive sleep apnea (OSA) are assumed to be part of the DS phenotype with a high prevalence but are often under recognized. This cross-sectional study of children with DS examines the caregiver-reported sleep behaviors of 108 children with DS, ranging in age from 1.50 to 13.40 years (mean = 5.18 years) utilizing a standardized assessment tool, the Children's Sleep Habit Questionnaire (CSHQ). The CSHQ revealed 76% of children with DS had sleep problems, which began at a young age, and continue to persist and may recur with increasing age. Furthermore, children with DS who undergone adenoidectomy and tonsillectomy for OSA continued to have sleep problems suggesting that ongoing monitoring of sleep issues is needed in this population. Implications of sleep problems and recommended anticipatory guidance and intervention are discussed.

Newborn screening for spinal muscular atrophy: Anticipating an imminent need.

Spinal muscular atrophy (SMA) is the most common genetic cause of infant mortality. Children with type I SMA typically die by the age of 2 years. Recent progress in gene modification and other innovative therapies suggest that improved outcomes may soon be forthcoming. In animal models, therapeutic intervention initiated before the loss of motor neurons alters SMA phenotype and increases lifespan. Presently, supportive care including respiratory, nutritional, physiatry, and orthopedic management can ameliorate clinical symptoms and improve survival rates if SMA is diagnosed early in life. Newborn screening could help optimize these potential benefits. A recent report demonstrated that SMA detection can be multiplexed at minimal additional cost with the assay for severe combined immunodeficiency, already implemented by many newborn screening programs. The public health community should remain alert to the rapidly changing developments in early detection and treatment of SMA.