Background/Objectives: CSCs are critical drivers of the tumor and stem cell phenotypes of glioblastoma (GBM) cells. Chromatin modifications play a fundamental role in driving a GBM CSC phenotype. The goal of this study is to further our understanding of how stem cell-driving events control changes in chromatin architecture that contribute to the tumor-propagating phenotype of GBM. Methods: We utilized computational analyses to identify a subset of clinically relevant genes that were predicted to be repressed in a Polycomb repressive complex 2 (PRC2)-dependent manner in GBM upon induction of stem cell-driving events. These associations were validated in patient-derived GBM neurosphere models using state-of-the-art molecular techniques to express, silence, and measure microRNA (miRNA) and gene expression changes. Advanced Poly(β-amino ester) nanoparticle formulations (PBAEs) were used to deliver miRNAs in vivo to orthotopic human GBM tumor models. Results: We show that glioma stem cell (GSC) formation and tumor propagation involve the crosstalk between multiple epigenetic mechanisms, resulting in the repression of the miRNAs that regulate PRC2 function and histone H3 lysine 27 tri-methylation (H3K27me3). We also identified miR-217-5p as an EZH2 regulator repressed in GSCs and showed that miR-217-5p reconstitution using advanced nanoparticle formulations re-activates the PRC2-repressed genes, inhibits GSC formation, impairs tumor growth, and enhances the effects of ionizing radiation in an orthotopic model of GBM. Conclusions: These findings suggest that inhibiting PRC2 function by targeting EZH2 with miR-217-5p advanced nanoparticle formulations could have a therapeutic benefit in GBM.
Real‐Time 2D Phase‐Contrast MRI to Assess Cardiac‐ and Respiratory‐Driven CSF Movement in Normal Pressure Hydrocephalus
ABSTRACT Background and Purpose In idiopathic normal pressure hydrocephalus (iNPH) patients, cerebrospinal fluid (CSF) flow is typically evaluated with a cardiac‐gated two‐dimensional (2D) phase‐contrast (PC) MRI through the cerebral aqueduct. This approach is limited by the evaluation of a single location and does not account for respiration effects on flow. In this study, we quantified the cardiac and respiratory contributions to CSF movement at multiple intracranial locations using a real‐time 2D PC‐MRI and evaluated the diagnostic value of CSF dynamics biomarkers in classifying iNPH patients. Methods This study included 37 participants: 16 iNPH, 10 Alzheimer's disease (AD), and 11 cognitively unimpaired (CU) controls. Anatomical and real‐time (non‐gated) PC images were acquired in a 3T Philips scanner. CSF flow was assessed at the foramen magnum, fourth ventricle, Sylvian fissure, lateral ventricle, and cerebral aqueduct. We calculated three CSF dynamics biomarkers: mean velocity amplitude, cardiac signal power, and respiratory signal power. Biomarkers from each location were evaluated for classifying iNPH versus AD and CU using support vector machine (SVM). A p ‐value of 0.05 or less was considered statistically significant. Results The velocity amplitude and cardiac signal power were significantly reduced in iNPH compared to CU ( p < 0.005) and AD ( p < 0.05) at the lateral ventricle. The SVM model using biomarkers from the lateral ventricle performed significantly better at classifying iNPH than the other locations in terms of accuracy ( p < 0.005) and diagnostic odds ratio ( p < 0.05). Conclusion Evaluation of CSF movement beyond the cerebral aqueduct may aid in identifying patients with and understanding the pathophysiology of iNPH.
Microstructural mapping of neural pathways in Alzheimer's disease using macrostructure‐informed normative tractometry
Abstract INTRODUCTION Diffusion‐weighted magnetic resonance imaging (dMRI) is sensitive to the microstructural properties of brain tissues and shows great promise in detecting the effects of degenerative diseases. However, many approaches analyze single measures averaged over regions of interest without considering the underlying fiber geometry. METHODS We propose a novel macrostructure‐informed normative tractometry (MINT) framework to investigate how white matter (WM) microstructure and macrostructure are jointly altered in mild cognitive impairment (MCI) and dementia. We compared MINT‐derived metrics with univariate diffusion tensor imaging (DTI) metrics to examine how fiber geometry may impact the interpretation of microstructure. RESULTS In two multisite cohorts from North America and India, we find consistent patterns of microstructural and macrostructural anomalies implicated in MCI and dementia; we also rank diffusion metrics' sensitivity to dementia. DISCUSSION We show that MINT, by jointly modeling tract shape and microstructure, has the potential to disentangle and better interpret the effects of degenerative disease on the brain's neural pathways. Highlights Changes in diffusion tensor imaging metrics may be due to macroscopic changes. Normative models encode normal variability of diffusion metrics in healthy controls. Variational autoencoder applied on tractography can learn patterns of fiber geometry. WM microstructure and macrostructure are modeled with multivariate methods. Transfer learning uses pretraining and fine‐tuning for increased efficiency.
Does Merit-based Incentive Payment System Performance Differ Based on Orthopaedic Surgeon Gender?
Background Value-based care payment and delivery models such as the recently implemented Merit-based Incentive Payment System (MIPS) aim to both provide better care for patients and reduce costs of care. Gender disparities across orthopaedic surgery, encompassing reimbursement, industry payments, referrals, and patient perception, have been thoroughly studied over the years, with numerous disparities identified. However, differences in MIPS performance based on orthopaedic surgeon gender have not been comprehensively evaluated. Questions/purposes After controlling for potentially confounding variables such as experience, geography, group size, and Medicare beneficiary characteristics, does MIPS performance differ between men and women orthopaedic surgeons? Methods The Medicare Physician and Other Practitioners and the Physician Compare databases were queried for years 2017, the first year MIPS was incorporated, and 2021, the most recent year with MIPS data published, to identify all physicians with a self-reported specialty of orthopaedic surgery. Together, these databases include all physicians who submitted at least 11 Medicare claims each year. Physician gender, US census region, years in practice, group practice size, billing practices, and patient demographic characteristics were collected for each surgeon. The MIPS Performance database was used to extract an overall MIPS performance score for each surgeon for each year. Payment adjustments, which are determined based on overall MIPS performance score, were derived for each surgeon based on the thresholds published by the Centers for Medicare & Medicaid Services. Payment adjustments include a negative adjustment, neutral adjustment, positive adjustment, or exceptional performance bonus and are associated with different thresholds each year. Statistical differences based on surgeon gender were assessed utilizing chi-square tests for categorical data, Student t-test for parametric continuous data, and Wilcoxon signed-rank test for nonparametric continuous data. Univariable and multivariable analyses were performed to analyze the relationship between surgeon gender and MIPS performance. Results After controlling for other patient and surgeon variables, woman gender was associated with a slightly increased MIPS performance score in 2021 (β 1.5 [95% confidence interval (CI) 0.02 to 3.00]; p = 0.047). However, this finding was statistically fragile, with the lower bound 95% CI being very close to the line of no difference. No association between surgeon gender and MIPS performance score was found in 2017 (β 2.2 [95% CI -0.5 to 4.9]; p = 0.11). Additionally, no relationship was found between gender and receiving either an exceptional performance MIPS bonus or a MIPS penalty in either year. Conclusion Women orthopaedic surgeons scored slightly higher on the MIPS in 2021, after controlling for surgeon and patient variables, despite providing care for a higher percentage of dual Medicare-Medicaid eligible patients and more medically complex patients. However, this finding was statistically fragile, with a small effect size, a 95% CI close to 0, and no consistent association in MIPS performance in 2017. Additionally, with no differences in MIPS performance bonuses or penalties, the clinical monetary impact of this difference may be minimal. Clinical Relevance The observed association between surgeon gender and MIPS performance scores in 2021, with women orthopaedic surgeons achieving slightly higher scores, raises interesting questions about potential differences in practice behaviors, communication styles, care quality, or other unmeasured variables. These findings may reflect true differences in how care is delivered or documented as scored by the MIPS. However, given the small effect size, statistical fragility, and inconsistency across years, there is a chance that this finding may be spurious. That being so, future research should aim to validate or refute these findings by examining a broader range of variables including documentation practices, practice behaviors, institutional differences, potential systemic biases in scoring methodologies, and patient outcomes. Understanding whether these differences are true is important to ensure that performance metrics like MIPS accurately and equitably reflect care quality.
Abstract Objective To assess the association of systolic and diastolic blood pressure (SBP and DBP) in recently menopausal women with white matter hyperintensity (WMH) volume later in life and determine whether short-term menopausal hormone therapy (mHT) modifies these associations. Methods Kronos Early Estrogen Prevention Study (KEEPS) was a multicenter, randomized, double-blinded, placebo-controlled 4-year mHT trial (oral conjugated equine estrogens or transdermal 17β-estradiol). KEEPS continuation was an observational follow-up of the participants 10 years after the end of mHT. The associations between KEEPS baseline blood pressure (BP) with KEEPS continuation WMH volume were examined adjusting for covariates in model 1 (age, total intracranial volume, study site, mHT type) and model 2 (additionally conventional CVD risk factors). Interaction terms (BP × mHT type) were added into the linear regression models. Results The mean ± SD ages of participants were 53 (±2) years at KEEPS baseline and 67 (±2) years at KEEPS continuation. Elevated BP at KEEPS baseline was associated with greater WMH volume measured 14 years later (model 1: SBP: β = 0.01 [95% CI, 0.001‐0.01] and DBP: β = 0.01 [95% CI, 0.003‐0.03]) and after additionally adjusting for CVD risk factors (model 2). We did not find any evidence that mHT versus placebo modified these associations. Topographically, higher BP was associated with greater periventricular WMH in the frontal and parietal lobes. Conclusion Our findings suggest the importance of maintaining normal BP in recently postmenopausal women with low CVD risk, irrespective of short-term mHT usage, to potentially reduce the risk of WMH later in life.
Overview of Alzheimer's Disease Neuroimaging Initiative and future clinical trials
Abstract The overall goal of the Alzheimer's Disease Neuroimaging Initiative (ADNI) is to optimize and validate biomarkers for clinical trials while sharing all data and biofluid samples with the global scientific community. ADNI has been instrumental in standardizing and validating amyloid beta (Aβ) and tau positron emission tomography (PET) imaging. ADNI data were used for the US Food and Drug Administration (FDA) approval of the Fujirebio and Roche Elecsys cerebrospinal fluid diagnostic tests. Additionally, ADNI provided data for the trials of the FDA‐approved treatments aducanumab, lecanemab, and donanemab. More than 6000 scientific papers have been published using ADNI data, reflecting ADNI's promotion of open science and data sharing. Despite its enormous success, ADNI has some limitations, particularly in generalizing its data and findings to the entire US/Canadian population. This introduction provides a historical overview of ADNI and highlights its significant accomplishments and future vision to pioneer “the clinical trial of the future” focusing on demographic inclusivity. Highlights The Alzheimer's Disease Neuroimaging Initiative (ADNI) introduced a novel model for public‐private partnerships and data sharing. It successfully validated amyloid and Tau PET imaging, as well as CSF and plasma biomarkers, for diagnosing Alzheimer's disease. ADNI generated and disseminated vital data for designing AD clinical trials.
Repeat TURBT in large volume high-grade non-invasive bladder cancer
Background The American Urological Association (AUA)/Society of Urology Oncology (SUO) guidelines recommend a repeat transurethral resection of bladder tumor (TURBT) for high-risk, non-invasive (HR Ta) nonmuscle invasive bladder cancer (NMIBC) patients. The evidence base for this recommendation is weak (grade C) and fraught with methodological shortcomings, such as the lack of adjuvant intravesical Bacillus Calmette Guerin (BCG) and single-center study designs. Objective We sought to evaluate the effect of repeat TURBT on recurrence-free survival at a population level in HR Ta NMIBC patients who completed BCG induction therapy. Methods High-grade Ta NMIBC patients who underwent TURBT for a ≥5 cm tumor were identified within the SEER-Medicare database. All patients completed induction BCG and were stratified into two groups: repeat TURBT within eight weeks of initial TURBT and a group without repeat TURBT (control group). The primary endpoint was the 3-year high-risk recurrence rate. Results A cohort of 604 patients was identified, with 93 (15.4%) undergoing a repeat TURBT within eight weeks of initial TURBT and 511 (84.6%) without a repeat TURBT. Patient demographic and clinical characteristics were similar overall. No significant difference in the 3-year recurrence rate was noted (repeat TURBT: 20.4% vs. control group: 15.7%, p = 0.25). After adjusting for demographic and clinical characteristics, no association between repeat TURBT and 3-year high-risk recurrence was observed (HR (95% CI): 1.27 (0.76, 2.11); p = 0.36). Conclusion Although our study contains several major limitations, our results suggest that repeat TURBT in large volume HG Ta NMIBC treated with induction BCG therapy was not associated with improved high-risk recurrence-free survival.
Effect of Sacubitril/Valsartan in Heart Failure with Preserved Ejection Fraction Across the Age Spectrum in PARAGON-HF
Abstract Aims To evaluate clinical outcomes, echocardiographic features, and the efficacy and safety of sacubitril/valsartan compared to valsartan across age groups in the PARAGON-HF trial. Methods and results A total of 4796 participants ≥50 years of age with chronic heart failure (HF) and left ventricular ejection fraction (LVEF) ≥45% were divided into three age groups: <65 years (n = 825), 65–74 years (n = 1772), and ≥75 years (n = 2199). Echocardiograms of 1097 patients were analysed in a standardized fashion at a core imaging laboratory. The primary composite outcome was total HF hospitalizations and cardiovascular (CV) death. Older patients were more likely to experience primary composite outcomes (compared to patients <65 years, adjusted rate ratio [aRR] for ≥75 years: 1.39, 95% confidence interval [CI] 1.21–1.61), total HF hospitalization (aRR 1.27, 95% CI 1.09–1.49), and CV death (adjusted hazard ratio [aHR] 2.04, 95% CI 1.44–2.87). Age did not modify the effect of sacubitril/valsartan compared to valsartan on primary composite endpoint (pinteraction = 0.79) in the overall population or in those with LVEF ≤57%. Older adults randomized to sacubitril/valsartan were more likely to develop hypotension compared to those receiving valsartan (pinteraction = 0.026). Older patients had smaller left ventricular chamber sizes, higher LVEF, and were more likely to have abnormal measures of diastolic function. Conclusion Older patients with HF with preserved ejection fraction had higher event rates than younger patients, more adverse events overall, and more hypotension when treated with sacubitril/valsartan; however, the treatment benefits of sacubitril/valsartan were retained in older patients.
Application of the revised criteria for diagnosis and staging of Alzheimer's disease: Drug development and clinical practice
Abstract The newly proposed revised criteria for diagnosis and staging of Alzheimer's disease (AD) by the Alzheimer's Association (AA) Workgroup represent a significant milestone in the field. These criteria offer objective measures for diagnosing and staging biological AD, bridging the gap between research and clinical care. Although implementation feasibility may vary across regions and settings, improving the availability and accuracy of biomarkers, especially plasma biomarkers, is expected to enhance the applicability of these criteria in clinical practice. The Fall 2023 Alzheimer's Association Research Roundtable (AARR) meeting served as a forum for gathering industry perspectives and feedback on these revised criteria, ensuring that the new criteria inform research, clinical trial design, and clinical care. In this article, we outline a summary of the newly proposed “Revised Criteria for Diagnosis and Staging of AD: AA Workgroup” and provide highlights from the AARR meeting in fall 2023. Highlights The Alzheimer's Association Research Roundtable (AARR) convened leaders from industry, academia, and government, to review the Revised Criteria for Diagnosis and Staging of AD: AA Workgroup , and gather industry perspectives and feedback on these revised criteria before its publication. The newly proposed revised criteria for diagnosis and staging of Alzheimer's disease (AD) by the AA's Workgroup represent a significant milestone, offering objective measures for the biological and staging of AD and bridging the gap between research and clinical care. Improving the availability and accuracy of biomarkers, especially blood‐based biomarkers (BBMs) is expected to improve clinical research and enhance the applicability of these criteria in clinical practice.