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Cryo-EM structure of TGFBIp fibrils driven by a corneal dystrophy-linked mutation enables design of peptide inhibitors of aggregation.

Corneal dystrophy is a heterogeneous group of diseases which manifests clinically by progressive corneal opacity and diminishing visual acuity. A group of corneal dystrophies are linked to autosomal dominant mutations in transforming growth factor β-induced protein (TGFBIp) and characterized by extracellular amyloid-positive deposits of unknown molecular structure. Here, we determined the cryogenic-electron microscopy (cryo-EM) structure of amyloid fibrils formed by the TGFBIp FAS1-4 domain with corneal dystrophy-linked mutation V624M. The L569 to N609 fibril core, which includes the Y571-R588 segment enriched in patient corneal deposits, forms symmetrical protofilaments with internal solvent channels. Leveraging this structure, we designed peptide inhibitors intended to bind onto fibril ends to block elongation, targeting the unequal growth of symmetrical protofilaments. Our G1 and H4 inhibitors exhibit concentration-dependent reduction of TGFBIp FAS1-4 aggregation as assessed by Thioflavin T, solubility fractionation, and electron microscopy. Our work illustrates how fibril structures can guide rational inhibitor design and suggests the targeting of protein aggregates as a therapeutic approach for corneal and ocular diseases.

betaIG-H3 Protein

Multiscale Modeling Primer: Focus on Chromatin and Epigenetics.

A central challenge in modern biology is to understand how molecular interactions produce cellular and organismal functions across vast spatiotemporal scales. Nowhere is this challenge more apparent than in the study of chromatin, where meters of DNA compact into a micron-sized nucleus. How this polymer folds is a dynamic process, regulated by epigenetic modifications-chemical changes to DNA and histones that involve only a handful of atoms. These small changes cooperate to produce emergent, higher-order structures that define cellular identity and function. To explain this system, we must integrate static, high-resolution snapshots from techniques like cryo-EM with dynamic, lower-resolution data from microscopy and genomics. Multiscale computational models are essential tools that bridge these experimental gaps and reveal the mechanisms of emergent behavior. However, the communication divide between experimental biologists and quantitative modelers often hampers progress. This primer addresses that gap. It first introduces the fundamental biology of chromatin and epigenetics at an introductory level for non-biologists audiences. We then survey the landscape of computational approaches, from atomistic to systems-level models, and connect them to the experimental data that inform and validate them at an introductory level for non-computationalists. We argue that the next frontier will require us to build integrative models that can predict how molecular perturbations mechanistically alter cellular phenotypes, which will open a new era of chromatin-targeted therapeutics.

Chromatin Dynamics

Craniotomy versus Endoscopic Membranectomy in the Treatment of Non-Homogeneous Chronic Subdural Hematoma: A Pilot Randomized Parallel-Group Active-Controlled Trial (EMiT CSDH 2).

BACKGROUND: Chronic subdural hematoma (CSDH) is a prevalent neurosurgical condition with persistent challenges related to recurrence. Endoscopic membranectomy (EM) has shown promising results in managing symptomatic non-homogenous (SNH)-CSDH, but comparative evidence against craniotomy with membranectomy (CM) is lacking. OBJECTIVES: To compare the safety and efficacy of EM versus CM in managing SNH-CSDH. MATERIALS AND METHODS: A pilot randomized parallel-group active-controlled open- labeled superiority trial from September 2023 to November 2024 at Government Kilpauk Medical College, Chennai, India. Sixty patients with SNH-CSDH were randomized into EM and CM groups. Recurrence was the primary outcome. Secondary outcomes included operative time, complications, radiological indices, pain, hospital stay, and functional recovery. All patients were followed for six months. RESULTS: No recurrence was observed in either group at six months. Two CM patients required reoperation on postoperative day one ( P = 0.15). EM was associated with shorter operative time ( P = 0.02), lower incidence of post-operative subdural residual fluid ( P = 0.015), better early hematoma reduction/subdural space reduction index ( P = 0.008), midline shift/symmetry improvement index ( P = 0.001), and lesser surgical site swelling ( P < 0.001). All patients were ambulant and had a Glasgow coma scale (GCS) 15 at discharge and at six months (including reoperated patients). Pain scores and functional recovery were comparable. EM patients had shorter hospital stays ( P = 0.004) and no significant complications. CONCLUSION: EM demonstrated favorable early radiological outcomes, fewer complications, and comparable functional recovery and recurrence versus CM in SNH-CSDH. Independent reproduction and larger multicentric trials are needed for validity and generalizability.

Humans

The Effectiveness of Passive Half-Time Interventions on Simulated Second-Half Performance in Elite Youth Soccer Players.

The half-time period in soccer provides a potentially important window to implement short-duration interventions aimed at maintaining second-half performance. However, passive rest has been associated with a decline in subsequent physical and technical performance. While re-warm-up strategies are well studied, little is known about the efficacy of technology-based, passive recovery modalities, device-supported interventions that require minimal active movement or physical exertion from the athlete, during half-time intervals. This study examined whether percussive therapy, electrical muscle stimulation, and pneumatic compression can mitigate second-half performance decline in male adolescent soccer players. Forty-three academy-level players (17.5 &#xb1; 0.6 years) completed a simulated soccer protocol including the Loughborough Soccer Pass Test (LSPT), repeated 20-meter sprints, and completed Total Quality of Recovery (TQR) assessments before and after half-time. Participants were randomized into one of four intervention groups during the 15-minute half-time interval: Passive Rest (CON), Percussive Therapy (Theragun Pro; TG), EMS (PowerDot; PD), and Pneumatic Compression (RecoveryAir; COMP). Linear mixed-effects models assessed Time &#xd7; Condition interactions for performance and recovery outcomes. Passive half-time rest led to significant deterioration in technical skill, sprint performance, and perceived recovery (p < .05) for the control group. TG and PD significantly improved technical performance (LSPT scores) compared to the control group (d = 0.65 and 0.72, respectively; p < .01). Furthermore, TG and COMP were effective at maintaining 20-meter sprint times (d = 0.58 and 0.49; p < .01), whereas the control group experienced significant slowing. Perceived recovery (TQR) scores significantly declined in the CON group from First Half to Second Half (16.5 &#xb1; 2.2 to 11.1 &#xb1; 2.3. However, this decline was significantly attenuated in all intervention groups: TG (17.5 &#xb1; 1.9 to 14.2 &#xb1; 1.9), PD (17.3 &#xb1; 1.9 to 15.1 &#xb1; 1.9), and COMP (17.6 &#xb1; 1.9 to 15.9 &#xb1; 2.0). Short-duration passive interventions during half-time can mitigate performance decline in adolescent soccer players. TG and EMS appear most effective for preserving technical skills, while COMP may support perceived recovery. These findings highlight practical strategies for optimizing in-game performance and inform evidence-based half-time protocols.

Humans

Patient and hospital factors associated with disparities in acute stroke treatment in community and academic hospitals.

BACKGROUND: Systemic barriers may affect identification, emergency transportation (EMS), and care coordination for people with stroke. We assessed patient- and hospital-level factors for associations with pre-hospital and emergency department care. We compared trends for patients presenting to an academic medical center (AMC) versus community hospitals (CHs). METHODS: We conducted a retrospective cohort study at an AMC (Tufts Medical Center) with 542 patients aged &#x2265;18&#xa0;years hospitalized with acute ischemic stroke or transient ischemic attack between 1/1/2018-12/31/2020 who presented directly to AMC or presented to AMC as a transfer from initial contact CHs. Primary outcomes were EMS use, stroke code activation, door-to-CT time, and door-to-needle time. RESULTS: AMC patients identifying as non-Hispanic Asian (odds ratio (OR)&#xa0;=&#xa0;0.25; 95% confidence interval (CI)&#xa0;=&#xa0;0.13-0.47) and Hispanic (OR&#xa0;=&#xa0;0.19; 95% CI&#xa0;=&#xa0;0.05-0.72) and CH non-Hispanic Black/African-American patients (OR&#xa0;=&#xa0;0.17; 95% CI&#xa0;=&#xa0;0.05-0.62) were less likely to use EMS compared to non-Hispanic white patients. Patients with non-English primary language were less likely to use EMS (OR&#xa0;=&#xa0;0.38; 95% CI&#xa0;=&#xa0;0.23-0.63) compared to English-speaking patients in both hospital settings. CH Hispanic patients were less likely to have stroke code activation (OR&#xa0;=&#xa0;0.24; 95% CI&#xa0;=&#xa0;0.05-0.86) compared to non-Hispanic white patients. CH patients were less likely to have stroke code activation (OR&#xa0;=&#xa0;0.12; 95% CI&#xa0;=&#xa0;0.07-0.19), had 31% shorter door-to-CT time (95% CI&#xa0;=&#xa0;15-43% shorter), and had 29% longer door-to-needle time (95% CI&#xa0;=&#xa0;5-58% longer). CONCLUSION: Patient-level factors and hospital setting were associated with differences in acute care suggesting opportunities for community outreach on EMS use, interventions to alleviate language barriers, and a need to address systemic biases.

Humans

Clinical performance of two lithium disilicate CAD/CAM materials in posterior Class II inlay restorations: A 48-month randomised split-mouth clinical trial.

OBJECTIVES: To compare the clinical performance of Amber Mill (AM) and IPS e.max CAD (EM) lithium disilicate computer-aided design/computer-aided manufacturing (CAD/CAM) materials in posterior Class II inlay restorations and characterise their baseline properties. METHODS: Thirty-four adults received paired AM and EM posterior Class II inlays (68 restorations) in a triple-blind randomised split-mouth trial followed for 48 months. Restorations were evaluated at baseline and annually using revised World Dental Federation (FDI) criteria, with fracture and retention as the primary endpoint. Baseline characterisation included flexural strength, shear bond strength, translucency parameter, and scanning electron microscopy. McNemar, Wilcoxon signed-rank, Friedman, one-way analysis of variance, Tukey post hoc, and inter-rater agreement analyses were used. RESULTS: At 48 months, 18 paired participants were available for primary analysis. Failures occurred in 2 of 18 AM restorations and in 3 of 18 EM restorations, corresponding to success rates of 88.9% and 83.3%, respectively, with no significant between-material difference (McNemar p = 1.000). No catastrophic bulk ceramic fracture was observed. Secondary FDI scores remained mostly within the clinically acceptable range; marginal staining deteriorated over time in both groups (p < .001) without significant between-material differences. Baseline material testing showed significant material- and translucency-dependent differences in flexural strength, shear bond strength, and translucency. CONCLUSIONS: Within the limitations of the 48-month follow-up and the tested Class II inlay indication, AM showed clinical performance comparable to EM. Observed clinical complications were related to retention or marginal/interface behaviour. CLINICAL SIGNIFICANCE: For posterior Class II lithium disilicate CAD/CAM inlays, medium-term complications were mainly retention/interface-related, suggesting adhesive-interface durability may be as important as baseline ceramic strength.

Humans

Comparison of three tracking methods to assess usage of two pediatric powered mobility devices for young children with cerebral palsy.

Powered mobility devices are underutilized for promoting self-initiated mobility in young children with cerebral palsy due to prioritization of walking, caregiver effort, device characteristics, and environmental factors. Understanding device usage patterns is important to assess the impact of powered mobility interventions on child outcomes. As part of clinical trial (NCT04684576), three objective tracking methods including integrated loggers, Global Positioning System trackers (GPST), and caregiver reported activity logs (CRAL) were compared to provide insights into device usage patterns. Metrics included play session frequency, session duration, total usage minutes, and unique usage days for two powered mobility devices: Modified Ride-on Cars (MROC) and the Permobil Explorer Mini (EM). Twelve children with cerebral palsy used each device for eight consecutive weeks in home and community settings (16&#x2009;weeks total), with device ordered randomized. Results showed no significant differences among tracking methods for the MROC. For the EM, only session duration differed between GPST and CRAL. Correlation analysis revealed variable relationships amongst tracking methods for both devices. The EM was used more frequently than the MROC, with significantly greater total usage minutes and session duration via CRAL, not GPST. The findings highlight the need for reliable tracking technologies that can be used across powered mobility devices.

Child, Preschool

Efficacy of current approaches to non-invasive diagnosis of skin cancer and the potential impact of artificial intelligence: A systematic review and meta-analysis.

BACKGROUND: Skin cancer is one of the most prevalent malignancies worldwide, particularly within Caucasian populations. This systematic review and meta-analysis aimed to quantitatively review the current literature on non-invasive diagnosis of skin cancer and evaluate the current evidence to support the use of tools in addition to, or in replacement of clinician face-to-face assessment. METHODS: A literature search was conducted for publications in PubMed, Medline and Embase databases. Articles describing accuracy, sensitivity, specificity and outcomes of their mode of assessment were included. A total of 208 articles met the inclusion criteria. RESULTS AND CONCLUSION: This systematic review and meta-analysis showed that the diagnostic performance of artificial intelligence (AI) in the interpretation of dermatoscopic images was high for melanoma diagnosis, basal cell carcinoma or malignancy, in comparison to dermatoscopic assessment alone by clinicians and experts. Although AI interpretation of images demonstrated higher sensitivity for melanoma diagnosis in comparison to clinical assessment combined with dermatoscopic assessment, it is unclear if this is also the case for basal cell carcinoma and squamous cell carcinoma diagnosis. Reflectance confocal microscopy, a non-invasive high resolution imaging technique, is known to have a high sensitivity for diagnosing cutaneous malignancy, and this may have applications within secondary care. Therefore, AI could help reduce resource burden and aid in clinical assessment, particularly within primary care settings.

Humans

Changes in heroin-related ambulance attendances following the introduction of a medically supervised injecting room in Victoria, Australia.

BACKGROUND: Injecting drug use contributes significantly to morbidity, mortality and broader social harms globally. Supervised Injecting Facilities (SIFs) are harm reduction interventions that reduce overdose risk and facilitate access to health services for marginalised individuals. While international evidence supports the effectiveness of SIFs, Australian population-level surveillance data quantifying their impact on emergency medical service utilisation remain limited. METHODS: Using data from the National Ambulance Surveillance System, we conducted a retrospective, interrupted time series analysis of heroin-related ambulance attendances within the local catchment of the Medically Supervised Injecting Room (MSIR) between January 2015 and December 2023. Supplementary analysis included comparisons with central Melbourne suburbs and the broader state of Victoria. Key intervention timepoints, including the opening of the MSIR on 30 June 2018, expansion of its operating hours in July 2019, and the COVID-19 pandemic from April 2020 to October 2021, were examined to assess changes in heroin-related attendances over time. Segmented regression models were used to assess changes in heroin-related ambulance attendance trends over time. RESULTS: At the time the MSIR opened, the model-predicted heroin-related ambulance attendance rate within the MSIR catchment was 123 per 100,000 population per month, equivalent to approximately 48 heroin-related ambulance attendances per month. Prior to implementation, the attendance rate was increasing by an estimated 0.74 per 100,000 population per month. Following the opening of the MSIR, the previously increasing trajectory reversed, with ambulance attendance rates declining by approximately 2.3 per 100,000 population per month relative to the pre-intervention trend. By the end of the study period (December 2023), the predicted monthly heroin-related ambulance attendance rate had declined to 36 per 100,000 population (approximately 14 attendances per month), representing an overall reduction of 70.7% from the time of MSIR implementation. These reductions persisted throughout the COVID-19 lockdown period and were sustained after restrictions lifted. Supplementary analysis showed no comparable reductions in the central Melbourne region or the remainder of Victoria. CONCLUSIONS: The introduction of the MSIR in Richmond was associated with a sustained reduction in heroin-related ambulance attendances within its catchment area. These findings provide strong population-level evidence that SIFs reduce acute heroin-related harms requiring emergency ambulance response, reinforcing their role as an effective harm reduction strategy within the Australian context.

Humans

Form and function of actin impacts actin health and aging.

The actin cytoskeleton is a fundamental and highly conserved structure that functions in diverse cellular processes, yet its direct contribution to organismal aging remains unclear. Here, we systematically interrogated how genetic and pharmacologic perturbations of actin structure and function influence lifespan and various hallmarks of aging in Caenorhabditis elegans. Whole-animal and tissue-specific knockdown of actin and key actin-binding proteins (ABPs)-arx-2 (Arp2/3), unc-60 (cofilin), and lev-11 (tropomyosin)-led to premature disruption of filament organization, reduced lifespan, and tissue-specific physiological defects. Actin dysfunction also displayed a more "aged" transcriptome using previously validated transcriptomics clocks, and broadly exacerbated many age-associated phenotypes, including mitochondrial dysfunction, lipid dysregulation, loss of proteostasis, impaired autophagy, and intestinal barrier failure. Pharmacological destabilization with Latrunculin A mirrored genetic knockdowns, while mild stabilization with Jasplakinolide modestly extended lifespan, emphasizing that optimal and finely tuned actin function is critical for healthy aging. Finally, analysis of human genome-wide association data revealed that common ACTB polymorphisms correlate with differences in age-related decline in gait speed, suggesting some links between aging and actin across organisms. Taken together, our results provide a comprehensive and publicly accessible resource that maps, for the first time, how changes in actin integrity correlate with diverse aging phenotypes across tissues. This descriptive framework is intended to enable future mechanistic discovery by offering a deep, unbiased dataset that can be integrated with emerging studies to define how actin dynamics can potentially influence aging.

actin