Sertoli Cells Improve Myogenic Differentiation, Reduce Fibrogenic Markers, and Induce Utrophin Expression in Human DMD Myoblasts

Duchenne muscular dystrophy (DMD) is an X-linked disease caused by mutations in DMD gene translating in lack of functional dystrophin and resulting in susceptibility of myofibers to rupture during contraction. Inflammation and fibrosis are critical hallmarks of DMD muscles, which undergo progressive degeneration leading to loss of independent ambulation in childhood and death by early adulthood. We reported that intraperitoneal injection of microencapsulated Sertoli cells (SeC) in dystrophic mice translates into recovery of muscle morphology and performance thanks to anti-inflammatory effects and induction of the dystrophin paralogue, utrophin at the muscle level, opening new avenues in the treatment of DMD. The aim of this study is to obtain information about the direct effects of SeC on myoblasts/myotubes, as a necessary step in view of a translational application of SeC-based approaches to DMD. We show that (i) SeC-derived factors stimulate cell proliferation in the early phase of differentiation in C2C12, and human healthy and DMD myoblasts; (ii) SeC delay the expression of differentiation markers in the early phase nevertheless stimulating terminal differentiation in DMD myoblasts; (iii) SeC restrain the fibrogenic potential of fibroblasts, and inhibit myoblast-myofibroblast transdifferentiation; and, (iv) SeC provide functional replacement of dystrophin in preformed DMD myotubes regardless of the mutation by inducing heregulin β1/ErbB2/ERK1/2-dependent utrophin expression. Altogether, these results show that SeC are endowed with promyogenic and antifibrotic effects on dystrophic myoblasts, further supporting their potential use in the treatment of DMD patients. Our data also suggest that SeC-based approaches might be useful in improving the early phase of muscle regeneration, during which myoblasts have to adequately proliferate to replace the damaged muscle mass.

Scoliosis in Pediatric Patients With Acute Flaccid Myelitis

Background: Acute flaccid myelitis (AFM) is an anterior horn disorder that manifests as rapid onset muscle weakness or paralysis. Development of scoliosis in pediatric AFM patients has been anecdotally reported, but associated risk factors or incidence have yet to be determined. Methods: Pediatric AFM patients treated over a 10-year period at a tertiary care center were identified. Patients were considered to have scoliosis if there was radiographic evidence of coronal curvature ≥15 degrees. Number of limbs affected, independent ambulation and head control, ventilator requirement at initial admission, and long-term ventilatory support (≥1 year) were recorded. Muscle strength and functional status were assessed by manual muscle testing (MMT) and Physical Abilities and Mobility Scale (PAMS), respectively. Areas of spinal cord lesion on initial MRI were recorded. Bivariate analyses were performed, with alpha set to 0.05. Results: Fifty-six AFM patients (27 scoliosis, 29 no scoliosis) were identified. Mean time from AFM presentation to scoliosis diagnosis was 0.93 years. Mean major Cobb angle at first radiograph was 31.7 ± 14.3 degrees. Lack of independent ambulation, ventilator dependence at time of admission or long term, number of limbs affected, and decreased MMT and PAMS scores were more common in patients who developed scoliosis (all, p < .05). Patients who developed scoliosis had more extensive thoracic spinal cord involvement on initial MRI (p = .03). Conclusion: AFM patients who develop scoliosis are more likely to be ventilator dependent, lack independent ambulation, and have more extensive thoracic SCI.

Design of a stepwise safety protocol for lower limb prosthetic risk management in a clinical investigation

<p><a>In research on lower limb prostheses, safety during testing and training is paramount. Lower limb prosthetic users risk unintentional loss of balance that can result in injury, fear of falling, and overall decreased confidence in their prosthetic leg. Here, we present a protocol for managing the risks during evaluation of active prosthetic legs with modifiable control systems. We propose graded safety levels, each of which must be achieved before advancing to the next one, from laboratory bench testing to independent ambulation in real-world environments. This ensures safety for the research participant and staff.</a></p>

Design of a stepwise safety protocol for lower limb prosthetic risk management in a clinical investigation

<p><a>In research on lower limb prostheses, safety during testing and training is paramount. Lower limb prosthetic users risk unintentional loss of balance that can result in injury, fear of falling, and overall decreased confidence in their prosthetic leg. Here, we present a protocol for managing the risks during evaluation of active prosthetic legs with modifiable control systems. We propose graded safety levels, each of which must be achieved before advancing to the next one, from laboratory bench testing to independent ambulation in real-world environments. This ensures safety for the research participant and staff.</a></p>

Short-Term Treatment With Teriparatide Restores Independent Ambulation in a Patient With Glucocorticoid-Induced Osteonecrosis of the Knees and Ankles

Teriparatide is a well-established treatment for osteoporosis. It is emerging as a promising treatment for osteonecrosis of the jaw and may be superior to alendronate for treating glucocorticoid-induced osteonecrosis of the femoral head and reduce collapse progression. However, few studies have investigated its efficacy in treating steroid-induced osteonecrosis affecting other sites such as the knee and ankle. Osteonecrosis treatment at these sites in early stages is limited to protected weight bearing and pain management. Surgical management is required for advanced stages. This case describes an unusual presentation of steroid-induced osteonecrosis in the bilateral lower extremities and illustrates the potential benefit of teriparatide as an alternative to surgery in managing this debilitating condition. A 25-year-old male with a history of a heart transplant for viral myocarditis was admitted to the hospital for severe bilateral lower extremity pain. His post-transplant course was complicated by giant cell myocarditis, treated with a prednisone taper from 80 mg to 7.5 mg daily over the course of one year. MRI showed diffuse osteonecrosis in the distal femora, medial femoral condyles, bilateral proximal tibias, left distal tibia, and bilateral ankles. A bone density test showed only mildly low bone mass with Z-scores of -0.8 at the right femur, -1.3 at the left femur and -1.3 at the lumbar spine. Due to progressive osteonecrosis on imaging and a decline in functional status over the next two months, following a discussion of risks, benefits and alternatives, he was started on daily teriparatide injections. Prior to therapy, he was using a walker and had difficulty ambulating more than a few feet. Within a month of teriparatide initiation, he reported improvement in both pain and mobility, and was able to walk independently into clinic. MRI two months later demonstrated no new lesions and significant improvement in previously necrotic areas. Our case highlights the importance of considering osteonecrosis at atypical locations in patients on chronic glucocorticoid therapy. It also demonstrates a promising role for teriparatide in treating steroid-induced osteonecrosis atypical sites and without concurrent osteoporosis.

Comparison of Follow-Up Length-Matched Single-Center Myelomeningocele Postnatal Closure Cohort to the Management of Myelomeningocele Study (MOMS) Trial Results

<b><i>Objective:</i></b> We sought to compare our large single-institution cohort of postnatal myelomeningocele closure to the 2 arms of the Management of Myelomeningocele Study (MOMS) trial at the designated trial time points, as well as assess outcomes at long-term follow-up among our postnatal cohort. <b><i>Methods:</i></b> A single-institutional retrospective review of myelomeningocele cases presenting from 1995 to 2015 at Children’s Hospital of Pittsburgh was performed. We compared outcomes at 12 and 30 months to both arms of the MOMS trial and compared our cohort’s outcomes at those designated time points to our long-term outcomes. Univariate statistical analysis was performed as appropriate. <b><i>Results:</i></b> One-hundred sixty-three patients were included in this study. All patients had at least 2-year follow-up, with a mean follow-up of 10 years (range 2–20 years). There was no difference in the overall distribution of anatomic level of defect. Compared to our cohort, the prenatal cohort had a higher rate of tethering at 12 months of age, 8 versus 1.8%. Conversely, the Chiari II decompression rate was higher in our cohort (10.4 vs. 1.0%). At 30 months, the prenatal cohort had a higher rate of independent ambulation, but our cohort demonstrated the highest rate of ambulation with or without assistive devices among the 3 groups. When comparing our cohort at these early time points to our long-term follow-up data, our cohort’s ambulatory function decreased from 84 to 66%, and the rate of detethering surgery increased almost 10-fold. <b><i>Conclusions:</i></b> This study demonstrated that overall ambulation and anatomic-functional level were significantly better among our large postnatal cohort, as well as having significantly fewer complications to both fetus and mother, when compared to the postnatal cohort of the MOMS trial. Our finding that ambulatory ability declined significantly with age in this patient population is worrisome for the long-term outcomes of the MOMS cohorts, especially given the high rates of cord tethering at early ages within the prenatal cohort. These findings suggest that the perceived benefits of prenatal closure over postnatal closure may not be as substantial as presented in the original trial, with the durability of results still remaining a concern.

International retrospective natural history study of LMNA-related congenital muscular dystrophy

Muscular dystrophies due to heterozygous pathogenic variants in LMNA gene cover a broad spectrum of clinical presentations and severity with an age of onset ranging from the neonatal period to adulthood. The natural history of these conditions is not well defined, particularly in patients with congenital or early onset who arguably present with the highest disease burden. Thus the definition of natural history endpoints along with clinically revelant outcome measures is essential to establishing both clinical care planning and clinical trial readiness for this patient group. We designed a large international cross-sectional retrospective natural history study of patients with genetically proven muscle laminopathy who presented with symptoms before two years of age intending to identify and characterize an optimal clinical trial cohort with pertinent motor, cardiac and respiratory endpoints. Quantitative statistics were used to evaluate associations between LMNA variants and distinct clinical events. The study included 151 patients (Median age at symptom onset 0.9 years, range: 0.0-2.0). Age of onset and age of death were significantly lower in patients who never aquired independent ambulation compared to patients who achieved independent ambulation. Most of the patients acquired independent ambulation (n = 101, 66.9%), and subsequently lost this ability (n = 86; 85%). The age of ambulation acquisition (Median: 1.2 years, range: 0.8-4.0) and age of ambulation loss (Median: 7 years, range 1.2-38.0) were significantly associated with the age of the first respiratory interventions and the first cardiac symptoms. Respiratory and gastrointestinal interventions occurred during first decade while cardiac interventions occurred later. Genotype-phenotype analysis showed that the most common mutation, p.Arg249Trp (20%), was significantly associated with a more severe disease course. This retrospective natural history study of early onset LMNA-related muscular dystrophy confirms the progressive nature of the disorder, initially involving motor symptoms prior to onset of other symptoms (respiratory, orthopedic, cardiac, and gastrointestinal). The study also identifies subgroups of patients with a range of long-term outcomes. Ambulatory status was an important mean of stratification along with the presence or absence of the p.Arg249Trp mutation. These categorizations will be important for future clinical trial cohorts. Finally, this study furthers our understanding of the progression of early onset LMNA-related muscular dystrophy and provides important insights into the anticipatory care needs of LMNA-related respiratory and cardiac manifestations.

Abstract P2: Results of a Prospective Observational Cohort Study of Tenecteplase as Standard of Care Stroke Thrombolytic

Background: Our 10-hospital network (2 CSCs, 2PSCs, 6 non-SCs) switched our standard stroke thrombolytic from alteplase (ALT) to tenecteplase (TNK; 0.25 mg/kg) in September 2019. Methods: We designed a two-year prospective cohort analysis of key processes and clinical outcomes for TNK-treated patients with planned quarterly assessments of feasibility and safety. The TNK cohort is compared to the retrospective historical cohort of all unique patients at these hospitals treated with ALT during the prior 2-year period (n=354). Analysis were taken from a local REDcap registry that recorded data fields required for Stroke Center certification and submission to Get-With-The Guidelines (GWTG). Interim results through three quarters ending June 30, 2020. Results: 151 patients were treated with TNK. The samples TNK v ALT were well matched on age (median, IQR) 66.0 (55.0, 76.0) v 67.0 (55.0, 78.8) and NIHSS at admission (median, IQR), 8 (4, 13) v 8 (4, 15). Symptomatic ICH (ECASS 3 definition) occurred in 2.0% of TNK and 2.3% of ALT treated patients; all but one symptomatic ICH occurred in patients treated with both thrombolytic and endovascular therapies. All cause in-hospital mortality was 3.3% and 6.8%, respectively. No differences were observed in early outcomes of discharge to home (52%, 53%) or independent ambulation (46%, 45%). Day 90 Rankin Score (last observation carried forward for missing values) was available only for TNK: mRS 0-1 in 46.4% (95%CI 38.6%-54.3%), 0-2 in 55.6% (95%CI 47.7%-63.3%). A significantly greater proportion of patients were treated with the lytic within 45 minutes of hospital arrival after the switch to TNK using Get-With-The-Guidelines DTN time criteria (Table), most notably at the primary stroke centers. Conclusions: To date, the transition to TNK was associated with reductions in DTN times and in Drip-and-Ship transfer times (see related abstract). No differences were seen on early indices of safety or efficacy.

Acute Functional Outcomes in Critically Ill COVID-19 Patients

Background: COVID-19 (Coronavirus Disease 2019) is a global cause of morbidity and mortality currently. We aim to describe the acute functional outcomes of critically ill coronavirus disease 2019 (COVID-19) patients after transferring out of the intensive care unit (ICU).Methods: 51 consecutive critically ill COVID-19 patients at a national designated center for COVID-19 were included in this exploratory, retrospective observational cohort study from January 1 to May 31, 2020. Demographic and clinical data were collected and analyzed. Functional outcomes were measured primarily with the Functional Ambulation Category (FAC), and divided into 2 categories: dependent ambulators (FAC 0–3) and independent ambulators (FAC 4–5). Multivariate analysis was performed to determine associations.Results: Many patients were dependent ambulators (47.1%) upon transferring out of ICU, although 92.2% regained independent ambulation at discharge. On multivariate analysis, we found that a Charlson Comorbidity Index of 1 or more (odds ratio 14.02, 95% CI 1.15–171.28, P = 0.039) and a longer length of ICU stay (odds ratio 1.50, 95% CI 1.04–2.16, P = 0.029) were associated with dependent ambulation upon discharge from ICU.Conclusions: Critically ill COVID-19 survivors have a high level of impairment following discharge from ICU. Such patients should be screened for impairment and managed appropriately by rehabilitation professionals, so as to achieve good functional outcomes on discharge.