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Mutations in nuclear genes encoding for mitochondrial proteins very long-chain acyl-CoA dehydrogenase (VLCAD) and trifunctional protein (TFP) cause rare autosomal recessive disorders. Studies in fibroblasts derived from patients with mutations in VLCAD and TFP exhibit mitochondrial defects. To gain insights on pathological changes that account for the mitochondrial deficits we performed quantitative proteomic, biochemical, and morphometric analyses in fibroblasts derived from subjects with three different VLCAD and three different TFP mutations. Proteomic data that was corroborated by antibody-based detection, indicated reduced levels of VLCAD and TFP protein in cells with VLCAD and TFP mutations respectively, which in part accounted for the diminished fatty acid oxidation capacity. Decreased mitochondrial respiratory capacity in cells with VLCAD and TFP mutations was quantified after glucose removal and cells with TFP mutations had lower levels of glycogen. Despite these energetic deficiencies, the cells with VLCAD and TFP mutations did not exhibit changes in mitochondria morphology, distribution, fusion and fission, quantified by either confocal or transmission electron microscopy and corroborated by proteomic and antibody-based protein analysis. Fibroblasts with VLCAD and to a lesser extend cells with TFP mutations had increased levels of mitochondrial respiratory chain proteins and proteins that facilitate the assembly of respiratory complexes. With the exception of reduced levels of catalase and glutathione S-transferase theta-1 in cells with TFP mutations, the levels of 45 proteins across all major intracellular antioxidant networks were similar between cells with VLCAD and TFP mutations and non-disease controls. Collectively the data indicate that despite the metabolic deficits, cells with VLCAD and TFP mutations maintain their proteomic integrity to preserve cellular and mitochondria architecture, support energy production and protect against oxidative stress.

Background Pediatric cardiomyopathy is a genetically heterogeneous disease with substantial morbidity and mortality. Current guidelines recommend genetic testing in children with hypertrophic, dilated, or restrictive cardiomyopathy, but practice variations exist. Robust data on clinical testing practices and diagnostic yield in children are lacking. This study aimed to identify the genetic causes of cardiomyopathy in children and to investigate clinical genetic testing practices. Methods and Results Children with familial or idiopathic cardiomyopathy were enrolled from 14 institutions in North America. Probands underwent exome sequencing. Rare sequence variants in 37 known cardiomyopathy genes were assessed for pathogenicity using consensus clinical interpretation guidelines. Of the 152 enrolled probands, 41% had a family history of cardiomyopathy. Of 81 (53%) who had undergone clinical genetic testing for cardiomyopathy before enrollment, 39 (48%) had a positive result. Genetic testing rates varied from 0% to 97% between sites. A positive family history and hypertrophic cardiomyopathy subtype were associated with increased likelihood of genetic testing (P=0.005 and P=0.03, respectively). A molecular cause was identified in an additional 21% of the 63 children who did not undergo clinical testing, with positive results identified in both familial and idiopathic cases and across all phenotypic subtypes. Conclusions A definitive molecular genetic diagnosis can be made in a substantial proportion of children for whom the cause and heritable nature of their cardiomyopathy was previously unknown. Practice variations in genetic testing are great and should be reduced. Improvements can be made in comprehensive cardiac screening and predictive genetic testing in first‐degree relatives. Overall, our results support use of routine genetic testing in cases of both familial and idiopathic cardiomyopathy. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01873963.

Background The unpredictable trajectory of pediatric advanced heart disease makes prognostication difficult for physicians and informed decision‐making challenging for families. This study evaluated parent and physician understanding of disease burden and prognosis in hospitalized children with advanced heart disease. Methods and Results A longitudinal survey study of parents and physicians caring for patients with advanced heart disease age 30 days to 19 years admitted for ≥7 days was performed over a 1‐year period (n=160 pairs). Percentage agreement and weighted kappa statistics were used to assess agreement. Median patient age was 1 year (interquartile range, 1–5), 39% had single‐ventricle lesions, and 37% were in the cardiac intensive care unit. Although 92% of parents reported understanding their child's prognosis “extremely well” or “well,” 28% of physicians thought parents understood the prognosis only “a little,” “somewhat,” or “not at all.” Better parent‐reported prognostic understanding was associated with greater preparedness for their child's medical problems (odds ratio, 4.7; 95% CI, 1.4–21.7, P=0.02). There was poor parent–physician agreement in assessing functional class, symptom burden, and likelihood of limitations in physical activity and learning/behavior; on average, parents were more optimistic. Many parents (47%) but few physicians (6%) expected the child to have normal life expectancy. Conclusions Parents and physicians caring for children with advanced heart disease differed in their perspectives regarding prognosis and disease burden. Physicians tended to underestimate the degree of parent‐reported symptom burden. Parents were less likely to expect limitations in physical activity, learning/behavior, and life expectancy. Combined interventions involving patient‐reported outcomes, parent education, and physician communication tools may be beneficial.

Problem Opportunities for self-directed learning were missing from our medical school curriculum in general and on our radiology electives specifically. Our objective was to explore the feasibility and benefits of using medical students in the development of our student-created teaching files. Approach In 2018, a website was developed at our institution to support medical student radiology education and create a repository for the online publication of student-developed teaching cases. Students participating in radiology clerkships at our institution had an opportunity to submit case presentations for publication to our online teaching file following peer review. The medical students participated in the peer review process facilitated by the faculty director of radiology undergraduate medical education. The faculty member oversaw the training of new student editors and the development of a peer review guide. Outcomes The peer review guide included goals of the teaching file project and direction regarding the peer review process. Student editors were trained using the peer review guide in conjunction with individual meetings with the faculty mentor. At twenty-four months, 82 student-developed cases had been published to the online teaching file following medical student peer review. The teaching file had garnered 3884 page views. Next Steps The medical student-led peer review process meets core competencies in self-directed learning. The authors plan to explore the application of peer-assisted learning theories to the editing and peer-review process.

Objectives: To evaluate the psychometric properties of the Transfer Assessment Instrument Questionnaire (TAI-Q), a self-assessment measure to evaluate transfer quality compared with clinician-reported measures. Design: Participants self-assessed transfers from their wheelchair to a mat table using the TAI-Q. For session 1, participants self-assessed their transfer both before and after reviewing a video of themselves completing the transfer (session 1). Self-assessment was completed for another transfer after a 10-minute delay (session 2, intrarater reliability) and after a 1- to 2-day delay (session 3, test-retest reliability). Self-assessment was compared with a criterion standard of an experienced clinician scoring the same transfers with the Transfer Assessment Instrument (TAI) version 4.0 (concurrent validity). Setting: 2017 National Veterans Wheelchair Games. Participants: Convenience sample of full-time wheelchair users (N=44). Interventions: Not applicable. Main Outcome Measures: TAI-Q and TAI. Results: After video review of their transfer, acceptable levels of reliability were demonstrated for total TAI-Q score for intrarater (intraclass correlation [ICC], 0.627) and test-retest reliability (ICC, 0.705). Moderate to acceptable concurrent validity was demonstrated with the TAI (ICC, 0.554-0.740). Participants tended to underestimate the quality of their transfer (reported more deficient items) compared with the TAI. However, this deficit decreased and reliability improved from pre-video review to post-video review and from session 1 to session 2. The minimum detectable change indicated that a change of 1.63 to 2.21 in the TAI-Q total score is needed to detect a significant difference in transfer skills. Conclusions: When paired with video review, the TAI-Q demonstrates moderate to acceptable levels of reliability and validity for the total score. Self-assessment was completed quickly (

Research communities across multiple disciplines have demonstrated an increasing concern about variations in the performance of social-ecological systems. In response to this concern, holistic research on resilience explores explanations for the performance of the systems under both predictable and unknown stressors and shocks. Embedded in broader systems, projects - which often involve a broad range of uncertainty and variability in performance outcomes - provide a fertile context in which to study resilience. On the other hand, projects involve temporary organising that is crucial in the extreme and changing contexts. In this essay, we frame a roadmap for the new theoretical domain of research at the intersection of resilience and projects. This framework intends to spark new research directions and can be used by scholars to investigate resilience at and across multiple levels-- individuals, groups/teams, projects, organisations, industries, and societies.

For pediatric pulmonary arterial hypertension (PAH) patients treated with parenteral prostanoids, response predictors, and the dose–effect relationship are ill defined. We determined the following: (1) which pulmonary vascular hemodynamic variable, after initiating prostanoids, best correlates with a significant clinical response; (2) the time interval after treatment when if no pulmonary hemodynamic improvement has occurred, none is ever likely to; and (3) the relationship between the prostanoid dose and its hemodynamic effects. This is a retrospective cohort study of 31 pediatric patients with Group 1 PAH treated with parenteral prostanoids. We found the following: (1) A fall in mean pulmonary arterial pressure (mPAP) of ≥25% predicted freedom from adverse clinical events with 80.7% accuracy and was also associated with improved functional class. (2) Thirty-three percent of patients who avoided an adverse clinical event demonstrated a ≥25% reduction in mPAP after 1 year of treatment, and 65% by 2 years. (3) Lower mPAP was seldom seen with doses of epoprostenol >60 ng/kg/min (100 ng/kg/min for treprostinil). Cardiac index was positively correlated with the dose of epoprostenol but not treprostinil; cardiac index >4 l/min/m 2 was seen at modest as well as high doses. We conclude that a ≥25% fall in mPAP on prostanoids indicates a positive clinical response which, if validated in other studies, may be useful for patient management or clinical trials. Some patients take more than 2 years for this change. Exceptionally high doses were generally not more effective than lower, although we could not determine whether lower doses would have been as effective.

Huntington disease (HD) is a devastating neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. Disrupted cortico-striatal transmission is an early event that contributes to neuronal spine and synapse dysfunction primarily in striatal medium spiny neurons, the most vulnerable cell type in the disease, but also in neurons of other brain regions including the cortex. Although striatal and cortical neurons eventually degenerate, these synaptic and circuit changes may underlie some of the earliest motor, cognitive, and psychiatric symptoms. Moreover, synaptic dysfunction and spine loss are hypothesized to be therapeutically reversible before neuronal death occurs, and restoration of normal synaptic function may delay neurodegeneration. One of the earliest synaptic alterations to occur in HD mouse models is enhanced striatal extrasynaptic NMDA receptor expression and activity. This activity is mediated primarily through GluN2B subunit-containing receptors and is associated with increased activation of cell death pathways, inhibition of survival signaling, and greater susceptibility to excitotoxicity. Death-associated protein kinase 1 (DAPK1) is a pro-apoptotic kinase highly expressed in neurons during development. In the adult brain, DAPK1 becomes re-activated and recruited to extrasynaptic NMDAR complexes during neuronal death, where it phosphorylates GluN2B at S1303, amplifying toxic receptor function. Approaches to reduce DAPK1 activity have demonstrated benefit in animal models of stroke, Alzheimer’s disease, Parkinson’s disease, and chronic stress, indicating that DAPK1 may be a novel target for neuroprotection. Here, we demonstrate that dysregulation of DAPK1 occurs early in the YAC128 HD mouse model, and contributes to elevated extrasynaptic GluN2B S1303 phosphorylation. Inhibition of DAPK1 normalizes extrasynaptic GluN2B phosphorylation and surface expression, and completely prevents YAC128 striatal spine loss in cortico-striatal co-culture, thus validating DAPK1 as a potential target for synaptic protection in HD and warranting further development of DAPK1-targeted therapies for neurodegeneration.

Background Long‐term survival in patients with truncus arteriosus is favorable, but there remains significant morbidity associated with ongoing reinterventions. We aimed to study the long‐term outcomes of the truncal valve and identify risk factors associated with truncal valve intervention. Methods and Results We retrospectively reviewed patients who underwent initial truncus arteriosus repair at our institution from 1985 to 2016. Analysis was performed on the 148 patients who were discharged from the hospital and survived ≥30 days postoperatively using multivariable competing risks Cox regression modeling. Median follow‐up time was 12.6 years (interquartile range, 5.0–22.1 years) after discharge from full repair. Thirty patients (20%) underwent at least one intervention on the truncal valve during follow‐up. Survival at 1, 10, and 20 years was 93.1%, 87.0%, and 80.9%, respectively. The cumulative incidence of any truncal valve intervention by 20 years was 25.6%. Independent risk factors for truncal valve intervention included moderate or greater truncal valve regurgitation (hazard ratio [HR], 4.77; P

Background: The utility of ANCA testing as an indicator of disease activity in ANCA-associated vasculitis (AAV) remains controversial. This study aimed to determine the association of ANCA testing by various methods and subsequent remission and examine the utility of a widely used automated addressable laser-bead immunoassay (ALBIA) to predict disease relapses.Methods: Data from the Rituximab vs. Cyclophosphamide for ANCA-Associated Vasculitis (RAVE) trial were used. ANCA testing was performed by direct ELISA, capture ELISA, and ALBIA. Cox proportional hazards regression models were used to evaluate the association of PR3-ANCA level and subsequent remission or relapse. The ALBIA results are routinely reported as >8 when the value is high. For this study, samples were further titrated. A decrease and increase in PR3-ANCA were defined as a halving or doubling in value, respectively.Results: A decrease in ANCA by ALBIA at 2 months was associated with shorter time to sustained remission (HR 4.52, p = 0.035). A decrease in ANCA by direct ELISA at 4 months was associated with decreased time to sustained remission (HR 1.77, p = 0.050). There were no other associations between ANCA decreases or negativity and time to remission. An increase in PR3-ANCA by ALBIA was found in 78 of 93 subjects (84%). Eleven (14%) had a PR3-ANCA value which required titration for detection of an increase. An increase of ANCA by ALBIA was associated with severe relapse across various subgroups.Conclusions: A decrease in ANCA by ALBIA at 2 months and by direct ELISA at 4 months may be predictive of subsequent remission. These results should be confirmed in a separate cohort with similarly protocolized sample and clinical data collection. A routinely used automated ALBIA for PR3-ANCA measurement is comparable to direct ELISA in predicting relapse in PR3-AAV. Without titration, 14% of the increases detected by ALBIA would have been missed. Titration is recommended when this assay is used for disease monitoring. The association of an increase in PR3-ANCA with the risk of subsequent relapse remains complex and is affected by disease phenotype and remission induction agent.

Functional magnetic resonance imaging (fMRI) is a valuable tool for studying neural activations in the central nervous system of animals due to its wide spatial coverage and non-invasive nature. However, the advantages of fMRI have not been fully realized in functional studies in mice, especially in the olfactory system, possibly due to the lack of suitable anesthesia protocols with spontaneous breathing. Since mice are widely used in biomedical research, it is desirable to evaluate different anesthesia protocols for olfactory fMRI studies in mice. Dexmedetomidine (DEX) as a sedative/anesthetic has been introduced to fMRI studies in mice, but it has a limited anesthesia duration. To extend the anesthesia duration, DEX has been combined with a low dose of isoflurane (ISO) or ketamine (KET) in previous functional studies in mice. In this report, olfactory fMRI studies were performed under three anesthesia protocols (DEX alone, DEX/ISO, and DEX/KET) in three different groups of mice. Isoamyl-acetate was used as an odorant, and the odorant-induced neural activations were measured by blood oxygenation-level dependent (BOLD) fMRI. BOLD fMRI responses were observed in the olfactory bulb (OB), anterior olfactory nuclei (AON), and piriform cortex (Pir). Interestingly, BOLD fMRI activations were also observed in the prefrontal cortical region (PFC), which are most likely caused by the draining vein effect. The response in the OB showed no adaptation to either repeated odor stimulations or continuous odor exposure, but the response in the Pir showed adaptation during the continuous odor exposure. The data also shows that ISO suppresses the olfactory response in the OB and AON, while KET enhances the olfactory response in the Pir. Thus, DEX/KET should be an attractive anesthesia for olfactory fMRI in mice.

The induction of lineage-specific gene programs are strongly influenced by alterations in local chromatin architecture. However, key players that impact this genome reorganization remain largely unknown. Here, we report that the removal of the special AT-rich binding protein 2 (SATB2), a nuclear protein known to bind matrix attachment regions, is a key event in initiating myogenic differentiation. The deletion of myoblast SATB2 in vitro initiates chromatin remodeling and accelerates differentiation, which is dependent on the caspase 7-mediated cleavage of SATB2. A genome-wide analysis indicates that SATB2 binding within chromatin loops and near anchor points influences both loop and sub-TAD domain formation. Consequently, the chromatin changes that occur with the removal of SATB2 lead to the derepression of differentiation-inducing factors while also limiting the expression of genes that inhibit this cell fate change. Taken together, this study demonstrates that the temporal control of the SATB2 protein is critical in shaping the chromatin environment and coordinating the myogenic differentiation program.