Intensive Continuous Positive Airway Pressure Adherence Program During Stroke Rehabilitation.

Background and Purpose- Continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea may improve stroke recovery, but adherence is poor. We assessed the effectiveness of an intensive CPAP adherence program during and after inpatient stroke rehabilitation on 3-month adherence and stroke recovery. Methods- In a single-arm study, 90 stroke rehabilitation patients were enrolled into an intensive CPAP adherence program. CPAP was continued after a run-in among qualifying patients with evidence of obstructive sleep apnea. The primary outcome was CPAP adherence, defined as ≥4 hours of use on ≥70% of days, over 3 months. Results- A total of 62 patients qualified for continued CPAP and 52 of these were willing to continue CPAP after discharge from rehabilitation. At 3 months, the average daily CPAP use was 4.7 hours (SD 2.6), and 32/52 (62%) patients were adherent. Factors significantly associated with adherence included more severe stroke, aphasia, and white race. Compared with nonadherent patients, adherent patients experienced greater improvements in the cognitive component of the Functional Independence Measure ( P=0.02) and in the National Institutes of Health Stroke Scale ( P=0.03). Conclusions- This intensive CPAP adherence program initiated during stroke rehabilitation can lead to CPAP adherence in the majority of patients with evidence of obstructive sleep apnea, including those with more severe stroke and aphasia, and may promote recovery. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02809430.

Whole genome sequencing reveals a 7 base-pair deletion in DMD exon 42 in a dog with muscular dystrophy.

Dystrophin is a key cytoskeletal protein coded by the Duchenne muscular dystrophy (DMD) gene located on the X-chromosome. Truncating mutations in the DMD gene cause loss of dystrophin and the classical DMD clinical syndrome. Spontaneous DMD gene mutations and associated phenotypes occur in several other species. The mdx mouse model and the golden retriever muscular dystrophy (GRMD) canine model have been used extensively to study DMD disease pathogenesis and show efficacy and side effects of putative treatments. Certain DMD gene mutations in high-risk, the so-called hot spot areas can be particularly helpful in modeling molecular therapies. Identification of specific mutations has been greatly enhanced by new genomic methods. Whole genome, next generation sequencing (WGS) has been recently used to define DMD patient mutations, but has not been used in dystrophic dogs. A dystrophin-deficient Cavalier King Charles Spaniel (CKCS) dog was evaluated at the functional, histopathological, biochemical, and molecular level. The affected dog's phenotype was compared to the previously reported canine dystrophinopathies. WGS was then used to detect a 7 base pair deletion in DMD exon 42 (c.6051-6057delTCTCAAT mRNA), predicting a frameshift in gene transcription and truncation of dystrophin protein translation. The deletion was confirmed with conventional PCR and Sanger sequencing. This mutation is in a secondary DMD gene hotspot area distinct from the one identified earlier at the 5' donor splice site of intron 50 in the CKCS breed.

Changes in Muscle Metabolism are Associated with Phenotypic Variability in Golden Retriever Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is an X-chromosome-linked disorder and the most common monogenic disease in people. Affected boys are diagnosed at a young age, become non-ambulatory by their early teens, and succumb to cardiorespiratory failure by their thirties. Despite being a monogenic condition resulting from mutations in the DMD gene, affected boys have noteworthy phenotypic variability. Efforts have identified genetic modifiers that could modify disease progression and be pharmacologic targets. Dogs affected with golden retriever muscular dystrophy (GRMD) have absent dystrophin and demonstrate phenotypic variability at the functional, histopathological, and molecular level. Our laboratory is particularly interested in muscle metabolism changes in dystrophin-deficient muscle. We identified several metabolic alterations, including myofiber type switching from fast (type II) to slow (type I), reduced glycolytic enzyme expression, reduced and morphologically abnormal mitochondria, and differential AMP-kinase phosphorylation (activation) between hypertrophied and wasted muscle. We hypothesize that muscle metabolism changes are, in part, responsible for phenotypic variability in GRMD. Pharmacological therapies aimed at modulating muscle metabolism can be tested in GRMD dogs for efficacy.

Relationship between individual neuron and network spontaneous activity in developing mouse cortex.

Spontaneous synchronous activity (SSA) that propagates as electrical waves is found in numerous central nervous system structures and is critical for normal development, but the mechanisms of generation of such activity are not clear. In previous work, we showed that the ventrolateral piriform cortex is uniquely able to initiate SSA in contrast to the dorsal neocortex, which participates in, but does not initiate, SSA (Lischalk JW, Easton CR, Moody WJ. Dev Neurobiol 69: 407-414, 2009). In this study, we used Ca(2+) imaging of cultured embryonic day 18 to postnatal day 2 coronal slices (embryonic day 17 + 1-4 days in culture) of the mouse cortex to investigate the different activity patterns of individual neurons in these regions. In the piriform cortex where SSA is initiated, a higher proportion of neurons was active asynchronously between waves, and a larger number of groups of coactive cells was present compared with the dorsal cortex. When we applied GABA and glutamate synaptic antagonists, asynchronous activity and cellular clusters remained, while synchronous activity was eliminated, indicating that asynchronous activity is a result of cell-intrinsic properties that differ between these regions. To test the hypothesis that higher levels of cell-autonomous activity in the piriform cortex underlie its ability to initiate waves, we constructed a conductance-based network model in which three layers differed only in the proportion of neurons able to intrinsically generate bursting behavior. Simulations using this model demonstrated that a gradient of intrinsic excitability was sufficient to produce directionally propagating waves that replicated key experimental features, indicating that the higher level of cell-intrinsic activity in the piriform cortex may provide a substrate for SSA generation.

Timing of surgical intervention after firearm-related spinal cord injury.

CONTEXT: Surgical management of firearm-related spinal cord injury (SCI) remains controversial, and there are no clear guidelines. Time to surgery, surgical indications, and patient characteristics on initial presentation in this group are not well understood, and these factors may impact the potential for neurologic recovery after operative intervention. OBJECTIVE: To understand the timing and factors affecting the timing of operative intervention after firearm-related SCI. METHODS: In a retrospective cohort study, patients with traumatic SCI from July 2012 to July 2022 (n = 1569) were identified from our level 1 trauma center Trauma Registry. Data was obtained from the trauma registry and chart review. Rates and timing of surgical intervention, initial injury severity measures, and general hospital outcomes were compared between firearm-related SCI and blunt trauma SCI. RESULTS: Patients with firearm-related SCI were less likely to undergo surgery compared to other etiologies (24.3% vs. 70.2%, P < 0.0001). Time to surgery for firearm-related SCI was longer than for other etiologies (49.2 ± 92.9 vs. 30.6 h ± 46.0, P = 0.012). Multiple measures of initial injury severity, including Injury Severity Score, Glasgow Coma Score, and emergency department disposition demonstrated more severe injury among patients with firearm-related SCI, and these patients often required other emergent surgeries prior to spine surgery (52%). CONCLUSIONS: There was a longer time to spine surgery among patients with firearm-related SCI compared to blunt trauma SCI, and patients with firearm-related SCI were more severely injured on initial presentation. Further research is needed to understand the complex relationship between patient injury severity, surgical intervention, surgical timing, and outcomes after firearm-related SCI.

Structure- and Property-Based Optimization of Efficient Pan-Bromodomain and Extra Terminal Inhibitors to Identify Oral and Intravenous Candidate I-BET787.

The bromodomain and extra terminal (BET) family of bromodomain-containing proteins are important epigenetic regulators that elicit their effect through binding histone tail N-acetyl lysine (KAc) post-translational modifications. Recognition of such markers has been implicated in a range of oncology and immune diseases and, as such, small-molecule inhibition of the BET family bromodomain-KAc protein-protein interaction has received significant interest as a therapeutic strategy, with several potential medicines under clinical evaluation. This work describes the structure- and property-based optimization of a ligand and lipophilic efficient pan-BET bromodomain inhibitor series to deliver candidate I-BET787 (70) that demonstrates efficacy in a mouse model of inflammation and suitable properties for both oral and intravenous (IV) administration. This focused two-phase explore-exploit medicinal chemistry effort delivered the candidate molecule in 3 months with less than 100 final compounds synthesized.

Utilization of rehabilitation services in violent versus nonviolent traumatic spinal cord injury.

BACKGROUND: Violence is the third leading cause of spinal cord injury (SCI) in the United States, and people with violence-related SCI have worse long-term outcomes compared to other traumatic SCI etiologies. Little is known, however, about the underlying reasons for these differences. Access to and utilization of rehabilitation services may differ in this population, but their outpatient care has not been previously investigated. OBJECTIVE: To evaluate differences in utilization patterns of outpatient rehabilitation services between people with violence-related SCI and other traumatic SCI etiologies. DESIGN: Retrospective cohort study. SETTING: Academic tertiary care hospital system. PATIENTS: A total of 41 patients with violence-related SCI residing in King County at the time of injury who completed inpatient rehabilitation (IPR) in our institution were identified from the hospital trauma registry and matched with 41 control patients with nonviolent traumatic SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): The number of appointments attended, canceled, and missed during the first year after discharge from IPR were obtained by chart review for physical medicine & rehabilitation (PM&R) physicians and therapy services. RESULTS: People with violence-related SCI had decreased follow-up with outpatient rehabilitation services after IPR discharge compared to non-violent traumatic SCI, including PM&R (2.50 ± 2.44 vs. 3.76 ± 2.21 visits, ß = -1.28, p = .017), physical therapy (8.91 ± 11.02 vs. 17.57 ± 15.26, ß = -9.79, p = .009), occupational therapy (4.28 ± 7.90 vs. 10.04 ± 14.42, ß = -6.18, p = .033), and recreational therapy (0.293 ± 0.955 vs. 1.37 ± 2.86, ß = -1.07, p = .035). The rate of missed appointments was also higher among people with violence-related SCI compared to controls for PM&R (25.2% ± 28.5% vs. 9.9% ± 16.5%, ß = 14.6%, p = .014) and physical therapy (26.0% ± 32.0% vs 4.2% ± 13.2%, ß = 22.1%, p = .009). CONCLUSIONS: Individuals with violence-related SCI had fewer follow-up appointments with PM&R physicians and other allied health professionals and were more likely to miss scheduled appointments compared to other traumatic SCI etiologies. Decreased outpatient follow-up may affect long-term outcomes for people with violence-related SCI.

Training Among Noncustodial Health Care Workers Caring for Patients Experiencing Incarceration: A Preliminary Investigation.

People experiencing incarceration in the United States receive much of their health care outside of custodial settings. Optimizing care in this setting requires further understanding of the training and experiences of noncustodial health care workers. We conducted a cross-sectional, exploratory survey of health care workers at a single academic institution to assess their training and experiences related to caring for this patient population. Of 333 respondents, 94.1% had cared for patients experiencing incarceration but only 22.5% had received any formal training, with 94.6% somewhat or very interested in further training. Common challenges included lack of privacy, difficulty obtaining patient history or completing an examination, and patient distress. Health care workers frequently experience challenges and report strong interest in further training to address knowledge gaps, and further detailed investigation is needed.

Stroke and breathing.

Stroke remains a leading cause of neurologic disability with wide ranging effects, including a variety of respiratory abnormalities. Stroke may influence the central control of the respiratory drive and breathing pattern, airway protection and maintenance, and the respiratory mechanics of inspiration and expiration. In the acute phase of stroke, the central control of breathing is affected by changes in consciousness, cerebral edema, and direct damage to brainstem respiratory centers, resulting in abnormalities in respiratory pattern and loss of airway protection. Common acute complications related to respiratory dysfunction include dysphagia, aspiration, and pneumonia. Respiratory control centers are located in the brainstem, and brainstem stroke causes specific patterns of respiratory dysfunction. Depending on the exact location and extent of stroke, respiratory failure may occur. While major respiratory abnormalities often improve over time, sleep-disordered breathing remains common in the subacute and chronic phases and worsens outcomes. Respiratory mechanics are impaired in hemiplegic or hemiparetic stroke, contributing to worse cardiopulmonary health in stroke survivors. Interventions to address the respiratory complications are under researched, and further investigation in this area is critical to improving outcomes among stroke survivors.

Trends and Disparities in Inpatient Rehabilitation of Adolescents: The Effect of Demographics, Injury Characteristics, and Facility Type.

BACKGROUND: Intensive rehabilitation of adolescents occurs in general and pediatric inpatient rehabilitation facilities (IRFs), but differences in admission and outcomes by facility type have not been thoroughly investigated, particularly among persons with spinal cord injury (SCI). OBJECTIVES: To investigate factors related to admission to pediatric or adult IRFs among adolescents and compare the rehabilitation outcomes between facility types. METHODS: Using a single-center retrospective cohort study design, demographic information, medical data, and rehabilitation outcomes were obtained by chart review of patients aged 15 to 18 years who received a rehabilitation medicine consultation at an urban level 1 trauma center between 2017 and 2019 (N = 96). Analysis was performed using R statistical software. RESULTS: SCI was the second most common diagnosis (21% of patients) and accounted for 36% of inpatient rehabilitation admissions. SCI patients were more likely to undergo rehabilitation at the level 1 trauma versus pediatric facility (relative risk [RR] = 2.43; 95% confidence interval [CI] = 1.08-5.44) compared to traumatic brain injury patients. Admission to trauma versus pediatric IRF was also associated with Black compared to White race (RR = 2.5; CI = 1.12-5.56), violence compared to other etiologies of injury (RR = 2.0; CI = 1.10-3.77), and Medicaid compared to private insurance (RR = 2.15; CI = 1.01-4.59). Admission to pediatric IRF was associated with longer length of stay than admission to adult IRF when adjusted for diagnosis (30.86 ± 21.82 vs. 24.33 ± 18.17 days; p = .046), but Functional Independence Measures did not differ. CONCLUSION: Adolescents with SCI and those experiencing systemic disadvantages, including racism and poverty, were more likely to be admitted to trauma compared to pediatric IRF.

Novel and modifiable factors associated with adherence to continuous positive airway pressure therapy initiated during stroke rehabilitation: An exploratory analysis of a prospective cohort study.

OBJECTIVE/BACKGROUND: Continuous positive airway pressure (CPAP) for the treatment of sleep apnea may improve stroke recovery but is limited by poor adherence. We evaluated baseline features and psychosocial factors associated with CPAP adherence among stroke patients enrolled in a pilot study of an intensive CPAP adherence protocol initiated during inpatient rehabilitation. PATIENTS/METHODS: In a retrospective analysis of a prospective cohort study, we compared participants adherent to CPAP (≥4 h for ≥70% of nights over 3 months) to non-adherent participants. Using mixed methods, we quantitatively compared baseline demographic and stroke-related factors associated with adherence and qualitatively compared facilitators and barriers to adherence. RESULTS: There were 32 adherent and 20 non-adherent participants. Quantitative analysis revealed more severe stroke, aphasia and white race were associated with adherence. Adherent compared to non-adherent participants also had fewer early CPAP complaints, especially claustrophobia. In a thematic qualitative analysis, facilitators of adherence included improvement in sleep and stroke symptoms, confidence in CPAP use, and positive treatment expectations. Conversely, barriers to adherence included both potentially modifiable factors (lack of confidence in CPAP use, discomfort with a new health technology, and common CPAP-related complaints), and less modifiable factors (social stressors, sleep disturbance, and lack of home social support). DISCUSSION: Adherence programs for CPAP use after stroke should address modifiable barriers, with early desensitization to improve CPAP-related complaints and claustrophobia, and training to address perceived self-efficacy with CPAP. Future studies should explore individual goals and barriers associated with CPAP use among stroke survivors to improve long-term CPAP adherence. CLINICAL TRIAL REGISTRATION NUMBER: NCT02809430.

Discovery of a potent series of non-steroidal non α-trifluoromethyl carbinol glucocorticoid receptor agonists with reduced lipophilicity.

A novel series of indazole non-steroidal glucocorticoid receptor agonist has been discovered. This series features a sulfonamide central core and meta amides which interact with the extended ligand binding domain. This series has produced some of the most potent and least lipophilic agonists of which we are aware such as 20a (NFκB pIC(50) 8.3 (100%), clogP 1.9). Certain analogues in this series also display evidence for modulated pharmacology.

GSK789: A Selective Inhibitor of the First Bromodomains (BD1) of the Bromo and Extra Terminal Domain (BET) Proteins.

Pan-bromodomain and extra terminal (BET) inhibitors interact equipotently with all eight bromodomains of the BET family of proteins. They have shown profound efficacy in vitro and in vivo in oncology and immunomodulatory models, and a number of them are currently in clinical trials where significant safety signals have been reported. It is therefore important to understand the functional contribution of each bromodomain to assess the opportunity to tease apart efficacy and toxicity. This article discloses the in vitro and cellular activity profiles of GSK789, a potent, cell-permeable, and highly selective inhibitor of the first bromodomains of the BET family.

Optimization of Potent ATAD2 and CECR2 Bromodomain Inhibitors with an Atypical Binding Mode.

Most bromodomain inhibitors mimic the interactions of the natural acetylated lysine (KAc) histone substrate through key interactions with conserved asparagine and tyrosine residues within the binding pocket. Herein we report the optimization of a series of phenyl sulfonamides that exhibit a novel mode of binding to non-bromodomain and extra terminal domain (non-BET) bromodomains through displacement of a normally conserved network of four water molecules. Starting from an initial hit molecule, we report its divergent optimization toward the ATPase family AAA domain containing 2 (ATAD2) and cat eye syndrome chromosome region, candidate 2 (CECR2) domains. This work concludes with the identification of (R)-55 (GSK232), a highly selective, cellularly penetrant CECR2 inhibitor with excellent physicochemical properties.

Discovery of a Bromodomain and Extraterminal Inhibitor with a Low Predicted Human Dose through Synergistic Use of Encoded Library Technology and Fragment Screening.

The bromodomain and extraterminal (BET) family of bromodomain-containing proteins are important regulators of the epigenome through their ability to recognize N-acetyl lysine (KAc) post-translational modifications on histone tails. These interactions have been implicated in various disease states and, consequently, disruption of BET-KAc binding has emerged as an attractive therapeutic strategy with a number of small molecule inhibitors now under investigation in the clinic. However, until the utility of these advanced candidates is fully assessed by these trials, there remains scope for the discovery of inhibitors from new chemotypes with alternative physicochemical, pharmacokinetic, and pharmacodynamic profiles. Herein, we describe the discovery of a candidate-quality dimethylpyridone benzimidazole compound which originated from the hybridization of a dimethylphenol benzimidazole series, identified using encoded library technology, with an N-methyl pyridone series identified through fragment screening. Optimization via structure- and property-based design led to I-BET469, which possesses favorable oral pharmacokinetic properties, displays activity in vivo, and is projected to have a low human efficacious dose.

Aryl aminopyrazole benzamides as oral non-steroidal selective glucocorticoid receptor agonists.

Aryl aminopyrazole amides capped with N-alkylbenzamides 13-16 are selective glucocorticoid receptor agonists. 2,6-Disubstituted benzamides have prednisolone-like potency or better in vitro. Good oral exposure was demonstrated in the rat, with compounds with lower lipophilicity, for example N-hydroxyethyl benzamides (e.g., 16e).

Aiming to Miss a Moving Target: Bromo and Extra Terminal Domain (BET) Selectivity in Constrained ATAD2 Inhibitors.

ATAD2 is a cancer-associated protein whose bromodomain has been described as among the least druggable of its class. In our recent disclosure of the first chemical probe against this bromodomain, GSK8814 (6), we described the use of a conformationally constrained methoxy piperidine to gain selectivity over the BET bromodomains. Here we describe an orthogonal conformational restriction strategy of the piperidine ring to give potent and selective tropane inhibitors and show structural insights into why this was more challenging than expected. Greater understanding of why different rational approaches succeeded or failed should help in the future design of selectivity in the bromodomain family.

Glucose Metabolism as a Pre-clinical Biomarker for the Golden Retriever Model of Duchenne Muscular Dystrophy.

PURPOSE: Metabolic dysfunction in Duchenne muscular dystrophy (DMD) is characterized by reduced glycolytic and oxidative enzymes, decreased and abnormal mitochondria, decreased ATP, and increased oxidative stress. We analyzed glucose metabolism as a potential disease biomarker in the genetically homologous golden retriever muscular dystrophy (GRMD) dog with molecular, biochemical, and in vivo imaging. PROCEDURES: Pelvic limb skeletal muscle and left ventricle tissue from the heart were analyzed by mRNA profiling, qPCR, western blotting, and immunofluorescence microscopy for the primary glucose transporter (GLUT4). Physiologic glucose handling was measured by fasting glucose tolerance test (GTT), insulin levels, and skeletal and cardiac positron emission tomography/X-ray computed tomography (PET/CT) using the glucose analog 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG). RESULTS: MRNA profiles showed decreased GLUT4 in the cranial sartorius (CS), vastus lateralis (VL), and long digital extensor (LDE) of GRMD vs. normal dogs. QPCR confirmed GLUT4 downregulation but increased hexokinase-1. GLUT4 protein levels were not different in the CS, VL, or left ventricle but increased in the LDE of GRMD vs. normal. Microscopy revealed diffuse membrane expression of GLUT4 in GRMD skeletal but not cardiac muscle. GTT showed higher basal glucose and insulin in GRMD but rapid tissue glucose uptake at 5 min post-dextrose injection in GRMD vs. normal/carrier dogs. PET/ CT with [18F]FDG and simultaneous insulin stimulation showed a significant increase (p = 0.03) in mean standard uptake values (SUV) in GRMD skeletal muscle but not pelvic fat at 5 min post-[18F]FDG /insulin injection. Conversely, mean cardiac SUV was lower in GRMD than carrier/normal (p < 0.01). CONCLUSIONS: Altered glucose metabolism in skeletal and cardiac muscle of GRMD dogs can be monitored with molecular, biochemical, and in vivo imaging studies and potentially utilized as a biomarker for disease progression and therapeutic response.

Use of the six-minute walk test to characterize golden retriever muscular dystrophy.

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder in which loss of the dystrophin protein causes progressive skeletal/cardiac muscle degeneration and death within the third decade. For clinical trials and supportive animal studies, DMD disease progression and response to treatment must be established using outcome parameters (biomarkers). The 6-minute walk test (6MWT), defined as the distance an individual can walk in 6 minutes, is commonly used in DMD clinical trials and has been employed in dogs to characterize cardiac and respiratory disease severity. Building on methods established in DMD and canine clinical studies, we assessed the 6MWT in dogs with the DMD genetic homolog, golden retriever muscular dystrophy (GRMD). Twenty-one cross-bred golden retrievers were categorized as affected (DMD mutation and GRMD phenotype), carrier (female heterozygous for DMD mutation and no phenotype), and normal (wild type DMD gene and normal phenotype). When compared to grouped normal/carrier dogs, GRMD dogs walked shorter height-adjusted distances at 6 and 12 months of age and their distances walked declined with age. Percent change in creatine kinase after 6MWT was greater in GRMD versus normal/carrier dogs at 6 months, providing another potential biomarker. While these data generally support use of the 6MWT as a biomarker for preclinical GRMD treatment trials, there were certain limitations. Results of the 6MWT did not correlate with other outcome parameters for GRMD dogs when considered alone and an 80% increase in mean distance walked would be necessary to achieve satisfactory power.