Citations

Abstract Repetitive head impacts sustained during American football have been associated with neuropathological changes such as white matter shear injuries. However, the impact of specific factors, such as age of first exposure and cumulative head impact burden, on white matter integrity remains unclear. This study investigated in vivo white matter microstructural changes using diffusion tensor imaging and tract-based spatial statistics in 165 male former American football players (mean age 57.3 years, range 45–74) and 52 unexposed asymptomatic male controls (mean age 59.4 years, range 45–74) in the DIAGNOSE CTE Research Project. Compared to controls, former football players exhibited significantly higher fractional anisotropy (FA) in 1.97% of the white matter skeleton (1552 voxels; Cohen’s d = 0.587) and higher tissue-corrected FA (FAt) in 1.48% of the white matter skeleton (1004 voxels; Cohen’s d = 0.616). No significant differences were observed for mean diffusivity, axial diffusivity, radial diffusivity, or free water between football players and controls. Among football players, there were no significant differences in the white matter microstructure between players diagnosed with traumatic encephalopathy syndrome and those without the diagnosis. Lower FA was significantly associated with older age (P < 0.00001) and an earlier age of first exposure to tackle football (P < 0.01), while lower FAt was associated with greater cumulative head impact burden, specifically higher linear acceleration (P < 0.04) and rotational force (P < 0.02). This study highlights the influential role of exposure factors on white matter microstructure in former American football players, as well as the utility of diffusion tensor imaging to aid in characterizing the long-term effects of repetitive head impacts in contact sport athletes.

Abstract Severe neuropathies with predominant involvement of motor fibres can resemble lower motor neuron disease (LMND) phenotypes. Given the fatal prognosis of LMND, identifying underlying autoimmune syndromes is crucial to provide treatment options to patients. We investigated a novel autoantibody binding pattern observed on murine teased sciatic nerve fibres. Target antigens were identified using immunoprecipitation combined with mass spectrometry. Target specificity of these autoantibodies was validated in cell-based assays, neutralization assays and knock-out models. A retrospective study cohort consisting of different neuropathies (chronic inflammatory demyelinating polyradiculopathy n = 86, Guillain–Barré syndrome n = 37, multifocal motor neuropathy n = 18, diabetic neuropathy n = 30, other inflammatory neuropathies n = 10), amyotrophic lateral sclerosis (n = 50), multiple sclerosis (n = 50) and healthy controls (n = 50) was negative for septin multimer autoantibodies. Histopathological analysis of skin and the sural nerve including electron microscopy was performed in one seropositive patient, and autoantibody binding was characterized in vitro. Extensive immunotherapy was initiated in one patient, with clinical and serological follow-up over 4 years. Among 3543 total samples tested, three patients (two male, one female)—diagnosed with the LMND variant of amyotrophic lateral sclerosis (aged 65, 72 and 79 years, respectively)—showed a novel and distinct autoantibody binding pattern of indirect immunofluorescence staining on peripheral nerves, targeting Schmidt–Lanterman incisures (SLIs), paranodes and the abaxonal myelin. Target identification and validation revealed septin multimers as autoantibody epitopes. Despite the primarily intracellular location of septins, autoantibody binding was evident in living myelinated dorsal root ganglia, primarily at SLIs (‘incisuropathy’). Septin multimer autoantibodies further initiated complement deposition on fixed and permeabilized cell-based assays. Sural nerve and skin biopsies showed inflammation, myelin and axonal pathology. Extensive immunotherapy in one patient was followed by disease stabilization over 3 years. The other two patients died of rapid disease progression: one of them received no immunotherapy while the other had ineffective treatments with single administrations of intravenous immunoglobulin and rituximab. Our data suggest that septin multimer autoimmunity occurs in severe motor-predominant neuropathies which can clinically resemble a neurodegenerative LMND. Screening for septin multimer autoantibodies should be considered in patients presenting with this phenotype. Follow-up studies need to determine the direct pathogenicity of septin multimer autoantibodies, their potential as a biomarker of an autoimmune syndrome and responses to immunotherapy in larger cohorts.

ABSTRACT Truncating mutations in the tumor suppressor STAG2 , which encodes a component of the cohesin complex, are prevalent across diverse human cancers. Here, we report that acute reconstitution of physiological STAG2 levels in STAG2 -mutant human glioblastoma multiforme cancer cells triggers a rapid reduction in the size of chromatin loops genome-wide. Despite this global change in chromatin loop size, early transcriptional responses to STAG2 restoration are limited to a small number of genes, most of which are induced by STAG2 reconstitution. Notably, the growth-suppressor EFEMP1 (Fibulin-3), a secreted glycoprotein that functions as an extracellular matrix-associated inhibitor of glioblastoma growth and invasion, was the only gene consistently induced across all experimental models. The most robust and conserved STAG2-induced genes all reside within intense chromatin loops whose anchors and overall intensity did not appear to change in response to STAG2 reconstitution. These findings suggest that inactivating mutations of STAG2 promote neoplastic transformation by alleviating a restriction on chromatin loop size, allowing for an expanded range of chromatin interactions that disrupts the maintenance of a tumor-suppressive transcriptome.

Background: Colorectal cancer (CRC) remains one of the common causes of cancer-related morbidity and mortality in the United States. Emerging increases in early-onset CRC and persistent disparities remain major public health concerns. Objective: To characterize long-term CRC incidence and mortality trends in the United States, with particular emphasis on identifying demographic groups experiencing rising or plateauing disease burden. Methods: We conducted a population-based ecological study using CRC incidence data from the United States Cancer Statistics database (1999–2022) and mortality data from CDC WONDER (1999–2023). Temporal trends were evaluated using Joinpoint regression to estimate annual percent change (APC) and average annual percent change (AAPC), stratified by age, sex, race/ethnicity, and urbanization level. Results: Overall CRC incidence and mortality declined during the study period (both AAPC approximately −2.08%). However, incidence increased significantly among adults younger than 55 years, particularly those aged 20–24 years. Mortality also increased among younger adults aged 25–44 years and remained elevated among individuals aged 45–54 years. Non-Hispanic Black individuals consistently experienced the highest incidence and mortality rates. Mortality declines plateaued in several older age groups after 2018–2020. Conclusions: Despite overall improvements in CRC burden, increasing incidence and mortality among younger adults and persistent disparities highlight the need for risk-stratified prevention, earlier detection strategies, and tailored therapeutic approaches.

Abstract Introduction: Asynchronous online courses are plagued with the challenge of engaging students consistently. Behavioral interventions, such as bottlenecks (enforced deadlines) and nudges (automated reminders), may modulate behaviors that lead to engagement and can now be easily applied and measured in a Learning Management System (LMS). Methods: This study included three groups of three asynchronous online courses each over three academic quarters. Two distinct behavioral interventions, bottlenecks and nudges, were implemented to increase engagement with the course compared to non-intervention controls. Results: The results showed that behavioral intervention tools increase student engagement with course materials by measures of increased student access to the course and reduced time to quiz completion. However, there was no significant impact in grades across the three groups. Conclusion: The use of nudges and bottlenecks as behavioral interventions to increase engagement in asynchronous courses for Clinical and Translational Science Education is recommended as part of best practice in course design with the same or similar structure.

BACKGROUND Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have expanded from metabolic therapeutics to agents with broad effects on inflammation, tissue repair, cutaneous and adipose biology, and aging-related pathways. Clinicians increasingly encounter cutaneous manifestations and aesthetic sequelae with important implications for dermatologic counseling and multidisciplinary care. OBJECTIVE To review current evidence regarding GLP-1RA effects on skin biology, inflammatory dermatoses, wound healing, cutaneous adverse events, and aesthetic aging. MATERIALS AND METHODS A narrative review of clinical, translational, and mechanistic literature was performed, emphasizing psoriasis, hidradenitis suppurativa, wound repair, skin hypersensitivity reactions, autoimmune blistering disease, and facial volume loss associated with pharmacologic weight reduction. RESULTS GLP-1RAs are hypothesized to improve inflammatory skin conditions and wound repair through anti-inflammatory, immunometabolic, and proreparative pathways. Yet, their use may also be associated with injection-site reactions, hypersensitivity eruptions, rare autoimmune blistering disorders, and clinically significant facial deflation and skin laxity. Current evidence is strongest for mechanistic plausibility and observational clinical signals, whereas dermatology-specific randomized trials remain limited. CONCLUSION GLP-1RAs exert bidirectional effects on cutaneous biology. Recognition of both therapeutic opportunities and potential aesthetic or adverse sequelae is important, with patient counseling ideally occurring within a multidisciplinary framework that integrates metabolic benefits with skin health and appearance.

BACKGROUND Glucagon-like peptide-1 receptor agonists (GLP-1RAs) exert systemic metabolic and anti-inflammatory effects that may be relevant to cellular senescence, a key driver of skin aging. However, human cutaneous data are lacking. OBJECTIVE To explore whether systemic GLP-1RA therapy translates to a detectable reduction in cutaneous senescence, quantified by epidermal p21 expression and supported by AI-driven facial imaging. MATERIALS AND METHODS In this controlled observational pilot study, 3 male adults (GLP-1RA n = 2; GLP-1RA–naïve control n = 1) underwent 3-mm punch biopsies from a standardized, sun-protected gluteal site to isolate intrinsic aging. Senescence was quantified through blinded whole-epidermis digital annotation of p21-positive nuclei. Clinical phenotypes were assessed using noninvasive cheek measurements and AI-based facial age estimation. RESULTS The cohort demonstrated divergence in senescence-associated biomarkers correlating with GLP-1RA exposure. The GLP-1RA–naïve control exhibited 8.0% ( n = 2,062 nuclei) epidermal senescence. By contrast, participants with 163 and 62 days of GLP-1RA exposure showed reduced senescence burdens of 2.4% ( n = 2,045) and 0.6% ( n = 1,636), respectively. Automated facial age estimation remained concordant with chronological age across subjects. CONCLUSION Systemic GLP-1RA exposure is associated with a substantial reduction in epidermal p21 expression in some subjects, suggesting a senomorphic effect and supporting further mechanistic studies at the interface of metabolic regulation and skin aging.