Citations

Introduction: White matter hyperintensity volume (WMHv) is an important and highly heritable cerebrovascular phenotype; however, manual or semi-automated approaches to clinically acquired MRI analysis hinder large-scale studies in acute ischemic stroke (AIS). In this work, we develop a high-throughput, fully automated WMHv analysis pipeline for clinical fluid-attenuated inversion recovery (FLAIR) images to facilitate rapid genetic discovery in AIS. Methods: Automated WMHv extraction from multiple subjects relies on significant pre-processing of medical scans, including co-registration of the images. To reduce the effects of anisotropic voxel sizes, each FLAIR image is upsampled using bi-cubic interpolation. Brain extraction is performed using RObust Brain EXtraction (ROBEX). Images are then registered to an in-house FLAIR template using Advanced Normalization Tools (ANTs). The spatial covariation of WMH is learned through principal component analysis (PCA) of manual outlines from 100 subjects. Areas of leukoaraiosis are identified and separated from other lesions using the PCA modes. Volumes are then computed using non-interpolated slices for each subject. Standard deviation (SD) in WMHv (9 subjects; 6 raters each) is calculated as a measure of variability. Good agreement between automated and manual outlines is assessed in 358 subjects (automated WMHv within 3SD of manual WMHv). Results: As part of the MRI - Gen etics I nterface E xploration (MRI-GENIE) study, WMHv were calculated on a set of 2703 FLAIR images of patients from 12 independent AIS cohorts (sites). Results are shown in Figure 1. Comparing manual and automated WMHv shows that 88% of the automated WMHv fall within 3 SD from the manual WMHv, suggesting good agreement. Conclusion: WMHv segmentation using a fully-automated pipeline for analysis of clinical MRIs is both feasible and accurate. Ongoing analysis of the extracted WMHv is expected to advance current knowledge of risks and outcomes in AIS.

BackgroundFor patients with sentinel lymph node (SLN)‐positive cutaneous melanoma, the Second Multicenter Selective Lymphadenectomy trial demonstrated equivalent disease‐specific survival (DSS) with active surveillance using nodal ultrasound versus completion lymph node dissection (CLND). Adoption and outcomes of active surveillance in clinical practice and in adjuvant therapy recipients are unknown.MethodsIn a retrospective cohort of SLN‐positive adults treated at 21 institutions in Australia, Europe, and the United States from June 2017 to November 2019, the authors evaluated the impact of active surveillance and adjuvant therapy on all‐site recurrence‐free survival (RFS), isolated nodal RFS, distant metastasis‐free survival (DMFS), and DSS using Kaplan‐Meier curves and Cox proportional hazard models.ResultsAmong 6347 SLN biopsies, 1154 (18%) were positive and had initial negative distant staging. In total, 965 patients (84%) received active surveillance, 189 (16%) underwent CLND. Four hundred thirty‐nine patients received adjuvant therapy (surveillance, 38%; CLND, 39%), with the majority (83%) receiving anti–PD‐1 immunotherapy. After a median follow‐up of 11 months, 220 patients developed recurrent disease (surveillance, 19%; CLND, 22%), and 24 died of melanoma (surveillance, 2%; CLND, 4%). Sixty‐eight patients had an isolated nodal recurrence (surveillance, 6%; CLND, 4%). In patients who received adjuvant treatment without undergoing prior CLND, all isolated nodal recurrences were resectable. On risk‐adjusted multivariable analyses, CLND was associated with improved isolated nodal RFS (hazard ratio [HR], 0.36; 95% CI, 0.15‐0.88), but not all‐site RFS (HR, 0.68; 95% CI, 0.45‐1.02). Adjuvant therapy improved all‐site RFS (HR, 0.52; 95% CI, 0.47‐0.57). DSS and DMFS did not differ by nodal management or adjuvant treatment.ConclusionsActive surveillance has been adopted for most SLN‐positive patients. At initial assessment, real‐world outcomes align with randomized trial findings, including in adjuvant therapy recipients.Lay Summary For patients with melanoma of the skin and microscopic spread to lymph nodes, monitoring with ultrasound is an alternative to surgically removing the remaining lymph nodes. The authors studied adoption and real‐world outcomes of ultrasound monitoring in over 1000 patients treated at 21 centers worldwide, finding that most patients now have ultrasounds instead of surgery. Although slightly more patients have cancer return in the lymph nodes with this strategy, typically, it can be removed with delayed surgery. Compared with up‐front surgery, ultrasound monitoring results in the same overall risk of melanoma coming back at any location or of dying from melanoma.

Abstract Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a life-time risk of 1 in 350 people and an unmet need for disease-modifying therapies. We conducted a cross-ancestry GWAS in ALS including 29,612 ALS patients and 122,656 controls which identified 15 risk loci in ALS. When combined with 8,953 whole-genome sequenced individuals (6,538 ALS patients, 2,415 controls) and the largest cortex-derived eQTL dataset (MetaBrain), analyses revealed locus-specific genetic architectures in which we prioritized genes either through rare variants, repeat expansions or regulatory effects. ALS associated risk loci were shared with multiple traits within the neurodegenerative spectrum, but with distinct enrichment patterns across brain regions and cell-types. Of the environmental and life-style risk factors obtained from literature, Mendelian randomization analyses indicated a causal role for high cholesterol levels. All ALS associated signals combined reveal a role for perturbations in vesicle mediated transport and autophagy, and provide evidence for cell-autonomous disease initiation in glutamatergic neurons.

Angiotensin II receptor blockers (telmisartan) prevent rodents from diet-induced obesity and improve their metabolic status. Hyperglycemia and obesity are associated with reduced cerebral blood flow and neurovascular uncoupling which may lead to behavioral deficits. We wanted to know whether a treatment with telmisartan prevents these changes in obesity. We put young mice on high-fat diet and simultaneously treated them with telmisartan. At the end of treatment, we performed laser speckle imaging and magnetic resonance imaging to assess the effect on neurovascular coupling and cerebral blood flow. Different behavioral tests were used to investigate cognitive function. Mice developed diet-induced obesity and after 16, not 8 weeks of high-fat diet, however, the response to whisker pad stimulation was about 30% lower in obese compared to lean mice. Simultaneous telmisartan treatment increased the response again by 10% compared to obese mice. Moreover, telmisartan treatment normalized high-fat diet-induced reduction of cerebral blood flow and prevented a diet-induced anxiety-like behavior. In addition to that, telmisartan affects cellular senescence and string vessel formation in obesity. We conclude, that telmisartan protects against neurovascular unit impairments in a diet-induced obesity setting and may play a role in preventing obesity related cognitive deficits in Alzheimer’s disease.

Abstract Cognitive resilience is an important modulating factor of cognitive decline in Alzheimer’s disease, but the functional brain mechanisms that support cognitive resilience remain elusive. Given previous findings in normal ageing, we tested the hypothesis that higher segregation of the brain’s connectome into distinct functional networks represents a functional mechanism underlying cognitive resilience in Alzheimer’s disease. Using resting-state functional MRI, we assessed both resting-state functional MRI global system segregation, i.e. the balance of between-network to within-network connectivity, and the alternate index of modularity Q as predictors of cognitive resilience. We performed all analyses in two independent samples for validation: (i) 108 individuals with autosomal dominantly inherited Alzheimer’s disease and 71 non-carrier controls; and (ii) 156 amyloid-PET-positive subjects across the spectrum of sporadic Alzheimer’s disease and 184 amyloid-negative controls. In the autosomal dominant Alzheimer’s disease sample, disease severity was assessed by estimated years from symptom onset. In the sporadic Alzheimer’s sample, disease stage was assessed by temporal lobe tau-PET (i.e. composite across Braak stage I and III regions). In both samples, we tested whether the effect of disease severity on cognition was attenuated at higher levels of functional network segregation. For autosomal dominant Alzheimer’s disease, we found higher functional MRI-assessed system segregation to be associated with an attenuated effect of estimated years from symptom onset on global cognition (P = 0.007). Similarly, for patients with sporadic Alzheimer’s disease, higher functional MRI-assessed system segregation was associated with less decrement in global cognition (P = 0.001) and episodic memory (P = 0.004) per unit increase of temporal lobe tau-PET. Confirmatory analyses using the alternate index of modularity Q revealed consistent results. In conclusion, higher segregation of functional connections into distinct large-scale networks supports cognitive resilience in Alzheimer’s disease.

Abstract Background: It is not known whether modifiable lifestyle factors that predict survival after invasive breast cancer differ by subtype. Methods: We analyzed data for 121,435 women diagnosed with breast cancer from 67 studies in the Breast Cancer Association Consortium with 16,890 deaths (8,554 breast cancer specific) over 10 years. Cox regression was used to estimate associations between risk factors and 10-year all-cause mortality and breast cancer–specific mortality overall, by estrogen receptor (ER) status, and by intrinsic-like subtype. Results: There was no evidence of heterogeneous associations between risk factors and mortality by subtype (Padj > 0.30). The strongest associations were between all-cause mortality and BMI ≥30 versus 18.5–25 kg/m2 [HR (95% confidence interval (CI), 1.19 (1.06–1.34)]; current versus never smoking [1.37 (1.27–1.47)], high versus low physical activity [0.43 (0.21–0.86)], age ≥30 years versus <20 years at first pregnancy [0.79 (0.72–0.86)]; >0–<5 years versus ≥10 years since last full-term birth [1.31 (1.11–1.55)]; ever versus never use of oral contraceptives [0.91 (0.87–0.96)]; ever versus never use of menopausal hormone therapy, including current estrogen–progestin therapy [0.61 (0.54–0.69)]. Similar associations with breast cancer mortality were weaker; for example, 1.11 (1.02–1.21) for current versus never smoking. Conclusions: We confirm associations between modifiable lifestyle factors and 10-year all-cause mortality. There was no strong evidence that associations differed by ER status or intrinsic-like subtype. Impact: Given the large dataset and lack of evidence that associations between modifiable risk factors and 10-year mortality differed by subtype, these associations could be cautiously used in prognostication models to inform patient-centered care.

Abstract To optimize the regenerative proficiency of stem cells, a cardiopoietic protein-based cocktail consisting of multiple growth factors has been developed and advanced into clinical trials for treatment of ischemic heart failure. Streamlining the inductors of cardiopoiesis would address the resource intensive nature of the current stem cell enhancement protocol. To this end, the microencapsulated-modified-mRNA (M3RNA) technique was here applied to introduce early cardiogenic genes into human adipose-derived mesenchymal stem cells (AMSCs). A single mesodermal transcription factor, Brachyury, was sufficient to trigger high expression of cardiopoietic markers, Nkx2.5 and Mef2c. Engineered cardiopoietic stem cells (eCP) featured a transcriptome profile distinct from pre-engineered AMSCs. In vitro, eCP demonstrated protective antioxidant capacity with enhanced superoxide dismutase expression and activity; a vasculogenic secretome driving angiogenic tube formation; and macrophage polarizing immunomodulatory properties. In vivo, in a murine model of myocardial infarction, intramyocardial delivery of eCP (600 000 cells per heart) improved cardiac performance and protected against decompensated heart failure. Thus, heart repair competent stem cells, armed with antioxidant, vasculogenic, and immunomodulatory traits, are here engineered through a protein-independent single gene manipulation, expanding the available regenerative toolkit.

Abstract Background: Continuing medical education (CME) often uses passive educational models including lectures. However, numerous studies have questioned the effectiveness of these less engaging educational strategies. Studies outside of CME suggest that engaged learning is associated with improved educational outcomes. However, measuring participants’ engagement can be challenging. We developed and determined the validity evidence for a novel instrument to assess learner engagement in CME.Methods: We conducted a cross-sectional validation study at a large, didactic-style CME conference. Content validity evidence was established through review of literature and previously published engagement scales and conceptual frameworks on engagement, along with an iterative process involving experts in the field, to develop an eight-item Learner Engagement Instrument (LEI). Response process validity was established by vetting LEI items on item clarity and perceived meaning prior to implementation, as well as using a well-developed online platform with clear instructions.. Internal structure validity evidence was based on factor analysis and calculating internal consistency reliability. Relations to other variables validity evidence was determined by examining associations between LEI and previously validated CME Teaching Effectiveness (CMETE) instrument scores. Following each presentation, all participants were invited to complete the LEI and the CMETE. Results: 51 out of 206 participants completed the LEI and CMETE (response rate 25%) Correlations between the LEI and the CMETE overall scores were strong (r=0.80). Internal consistency reliability for the LEI was excellent (Cronbach’s alpha=0.96). To support validity to internal structure, a factor analysis was performed and revealed a two dimensional instrument consisting of internal and external engagement domains. The internal consistency reliabilities were 0.96 for the internal engagement domain and 0.95 for the external engagement domain.Conclusion: Engagement, as measured by the LEI, is strongly related to teaching effectiveness. The LEI is supported by robust validity evidence including content, response process, internal structure, and relations to other variables. Given the relationship between learner engagement and teaching effectiveness, identifying more engaging and interactive methods for teaching in CME is recommended.

9522 Background: Many MSCC patients live long enough to develop a recurrence in the irradiated spinal area. This is the first prospective study comparing different RT schedules for local control (LC) of MSCC. Methods: 265 patients treated with RT alone (1/06–12/07) were included in this prospective non-randomized study. The primary goal was to compare short-course (1×8 Gy/5×4 Gy, N=131) and long-course RT (10×3 Gy/15×2.5 Gy/20×2 Gy, N=134) for 1-year LC. Secondary endpoints were motor function and 1-year survival (OS). Dutch patients received short-course, and German patients long-course RT. The analysis of LC (no MSCC recurrence in the irradiated spinal area) included the 224 patients with improvement or no change of motor deficits during RT. The difference in 1-year LC was previously reported to be 14% between short- and long-course RT. For a statistical power of 90 % (significance level 5%), ≥218 patients were required to detect this difference. Univariate analyses (UVA) for LC and OS were performed with Kaplan-Meier-method and log-rank test, multivariate analyses (MVA) with the Cox proportional hazards model. UVA and MVA for motor function were performed with the ordered-logit-model. Eleven additional factors were evaluated. Results: 1-year LC was 61% after short-course RT and 81% after long-course RT (P=0.005). On MVA, improved LC was only associated with long-course RT (P=0.018). Motor function improved in 37% after short- and 39% after long-course RT (P=0.95). Improved motor function was associated with better performance status (P=0.015), favorable tumor (P=0.034), and slower development of motor deficits (P<0.001). 1-year OS was 23% after short- and 30% after long-course RT (P=0.28). On MVA, improved OS was associated with better performance status (P<0.001), no visceral metastases (P<0.001), involvement of 1–3 vertebrae (P=0.040), ambulatory status (P=0.038), and bisphosphonates (P<0.001). Conclusions: Long-course RT was associated with better LC, similar functional outcome, and similar OS compared to short-course RT. Patients with a favorable OS prognosis should receive long-course RT, and those with a poor OS prognosis should receive short-course RT. [Table: see text]

Abstract Background Continuing medical education (CME) often uses passive educational models including lectures. However, numerous studies have questioned the effectiveness of these less engaging educational strategies. Studies outside of CME suggest that engaged learning is associated with improved educational outcomes. However, measuring participants’ engagement can be challenging. We developed and determined the validity evidence for a novel instrument to assess learner engagement in CME. Methods We conducted a cross-sectional validation study at a large, didactic-style CME conference. Content validity evidence was established through review of literature and previously published engagement scales and conceptual frameworks on engagement, along with an iterative process involving experts in the field, to develop an eight-item Learner Engagement Instrument (LEI). Response process validity was established by vetting LEI items on item clarity and perceived meaning prior to implementation, as well as using a well-developed online platform with clear instructions. All item responses were double-coded for statistical analysis, using a dedicated survey research center. Internal structure validity evidence was based on factor analysis and calculating internal consistency reliability. Relations to other variables validity evidence was determined by examining associations between LEI and previously validated CME Teaching Effectiveness (CMETE) instrument scores. Following each presentation, all participants were invited to complete the LEI and the CMETE. Results A total of 2486 LEI and CMETE surveys were submitted during the 5-day course. Correlations between the LEI and the CMETE overall scores were strong (r = 0.80). Internal consistency reliability for the LEI was excellent (Cronbach’s alpha = 0.96). To support validity to internal structure, a factor analysis was performed and revealed a two dimensional instrument consisting of internal and external engagement domains. The internal consistency reliabilities were 0.96 for the internal engagement domain and 0.95 for the external engagement domain. Conclusion Engagement, as measured by the LEI, is strongly related to teaching effectiveness. The LEI is supported by robust validity evidence including content, response process, internal structure, and relations to other variables. Given the relationship between learner engagement and teaching effectiveness, identifying more engaging and interactive methods for teaching in CME is recommended.