Correlation of FAPI PET Uptake with Immunohistochemistry in Explanted Lungs from Patients with Advanced Interstitial Lung Disease.

Recent studies have demonstrated promising results of fibroblast activation protein (FAP) inhibitor (FAPI) PET in prognosticating and monitoring interstitial lung diseases (ILDs). As a first step toward successful translation, our primary aim was to validate the FAPI PET uptake through immunohistochemistry in patients with advanced ILD who underwent lung transplantation after a FAPI PET scan. Methods: This is a preliminary analysis of a single-center, open-label, single-arm, prospective exploratory biodistribution study of 68Ga-FAPI-46 PET imaging in patients with ILD (NCT05365802). Patients with ILD confirmed by high-resolution CT and scheduled for lung transplant were included. Tissue samples of explanted lungs were obtained from both the central and peripheral lung parenchyma of each lobe. Additional samples were obtained from areas of the lung corresponding to regions of FAPI PET activity. Immunohistochemical staining was performed with an anti-FAP antibody. Percentages of FAP immunohistochemistry-positive area were measured semiautomatically using QuPath software. SUVs in the areas of pathologic samples were measured on FAPI PET/CT by referencing the gross photomap of the explanted lung. A Spearman correlation coefficient test was used to assess the relationship between FAPI PET uptake and FAP immunohistochemical expression in each specimen. Results: Four patients with advanced ILD who underwent FAPI PET/CT before lung transplantation were included. The types of ILD were idiopathic pulmonary fibrosis (n = 2), rheumatoid arthritis-associated ILD (n = 1), and nonspecific interstitial pneumonia (n = 1). FAPI uptake was visualized mainly in the fibrotic area on CT. Twenty-nine surgical pathology samples from 3 patients were analyzed. FAP staining was predominantly positive in fibroblastic foci. FAPI PET SUVmax and SUVmean showed a positive correlation with the immunohistochemical FAP expression score (SUVmax: r = 0.57, P = 0.001; SUVmean: r = 0.54, P = 0.002). Conclusion: In this analysis conducted in patients who underwent lung transplantation after a FAPI PET scan, FAPI PET uptake was positively correlated with FAP immunohistochemistry. These findings provide a rationale for further investigation of FAPI PET as a potential imaging biomarker for ILD.

Dynamics of Daily Glioblastoma Evolution During Chemoradiation Therapy on the 0.35T Magnetic Resonance Imaging-Linear Accelerator.

PURPOSE: Glioblastoma changes during chemoradiation therapy are inferred from magnetic resonance imaging (MRI) before and after treatment but are rarely investigated due to logistics of frequent MRI. Using a combination MRI-linear accelerator (MRI-linac), we evaluated changes during daily chemoradiation therapy. METHODS AND MATERIALS: Patients with glioblastoma were prospectively imaged daily during chemoradiation therapy on 0.35T MRI-linac and at 3 timepoints with and without contrast on standalone high-field MRI. Tumor or edema (lesion) and resection cavity dynamics throughout treatment were analyzed and compared with standalone T1 postcontrast (T1+C) and T2 volumes. RESULTS: Of 36 patients included in this analysis, 8 had cavity only, 12 had lesion only, and 16 had both cavity and lesion. Of these, 64% had lesion growth and 46% had cavity shrinkage during treatment on MRI-linac scans. The average MRI-linac migration distance was 1.3 cm (range, 0-4.1 cm) for lesion and 0.6 cm (range, 0.1-2.1 cm) for cavity. Standalone versus MRI-linac volumes correlated strongly with R2 values: 0.991 (T2 vs MRI-linac cavity), 0.972 (T1+C vs MRI-linac cavity), and 0.973 (T2 vs MRI-linac lesion). There was a moderate correlation between T1+C and MRI-linac lesion (R2 = 0.609), despite noncontrast MRI-linac inability to separate contrast enhancement from surrounding nonenhancing tumor and edema. From pretreatment to posttreatment in patients with all available scans (n = 35), T1+C and MRI-linac lesions changed together-shrank (n = 6), grew (n = 12), or unchanged (n = 8)-in 26 (74%) patients. Another 9 patients (26%) had growth on MRI-linac, although the T1+C component shrank. In no patient did T1+C lesion grow while MRI-linac lesion shrank. CONCLUSIONS: Anatomic changes are seen in patients with glioblastoma imaged daily on MRI-linac throughout the chemoradiation therapy course. As surgical resection cavities shrink, margins may be reduced to save normal brain. Patients with unresected or growing lesions may require margin expansions to cover changes. Limited volume glioblastoma boost trials could consider triggered gadolinium contrast administration for evaluation of adaptive radiation therapy when lesion growth is seen on noncontrast MRI-linac.

Microglial TREM2 promotes phagocytic clearance of damaged neurons after status epilepticus.

In the central nervous system, triggering receptor expressed on myeloid cells 2 (TREM2) is exclusively expressed by microglia and is critical for microglial proliferation, migration, and phagocytosis. Microglial TREM2 plays an important role in neurodegenerative diseases, such as Alzheimer's disease and amyotrophic lateral sclerosis. However, little is known about how TREM2 affects microglial function within epileptogenesis. To investigate this, we utilized male TREM2 knockout (KO) mice within the murine intra-amygdala kainic acid seizure model. Electroencephalographic analysis, immunocytochemistry, and RNA sequencing revealed that TREM2 deficiency significantly promoted seizure-induced pathology. We found that TREM2 KO increased both the severity of acute status epilepticus and the number of spontaneous recurrent seizures characteristic of chronic focal epilepsy. Phagocytic clearance of damaged neurons by microglia was also impaired by TREM2 KO and reduced phagocytic activity correlated with increased spontaneous seizures. Analysis of human tissue from patients who underwent surgical resection for drug resistant temporal lobe epilepsy also showed a negative correlation between expression of the microglial phagocytic marker CD68 and focal to bilateral tonic-clonic generalized seizure history. These results indicate that microglial TREM2 and phagocytic activity are important to epileptogenic pathology.

Changing Your Martini Can Still Give You a Hangover.

The Martini 3.0 coarse-grained force field, which was parametrized to better capture transferability in top-down coarse-grained models, is analyzed to assess its accuracy in representing thermodynamic and structural properties with respect to the underlying atomistic representation of the system. These results are compared to those obtained following the principles of statistical mechanics that start from the same underlying atomistic system. To this end, the potentials of mean force for lateral association in Martini 3.0 binary lipid bilayers are decomposed into their entropic and enthalpic components and compared to those of corresponding atomistic bilayers that have been projected onto equivalent coarse-grained mappings but evolved under the fully atomistic forces. This is accomplished by applying the reversible work theorem to lateral pair correlation functions between coarse-grained lipid beads taken at a range of different temperatures. The entropy-enthalpy decompositions provide a metric by which the underlying statistical mechanical properties of Martini can be investigated. Overall, Martini 3.0 is found to fail to properly partition entropy and enthalpy for the PMFs compared to the mapped all-atom results, despite changes made to the force field from the Martini 2.0 version. This outcome points to the fact that the development of more accurate top-down coarse-grained models such as Martini will likely necessitate temperature-dependent terms in the corresponding CG force-field; although necessary, this may not be sufficient to improve Martini. In addition to the entropy-enthalpy decompositions, Martini 3.0 produces an incorrect undulation spectrum, in particular at intermediate length scales of biophysical pertinence.

Sex Differences in Prescription Patterns and Medication Adherence to Guideline-directed Medical Therapy Among Patients with Ischemic Stroke.

Background: Ischemic stroke is a leading cause of death and disability. Society guidelines recommend pharmacotherapies for secondary stroke prevention. However, the role of sex differences in prescription and adherence to guideline-directed medical therapies (GDMT) after ischemic stroke remains understudied. The aim of this study was to examine sex differences in prescription and adherence to GDMT at 1-year after ischemic stroke in a cohort of commercially insured patients. Methods: Using the Truven Health MarketScan database from 2016-2020, we identified patients admitted with ischemic stroke. GDMT was defined as any statin, antihypertensive, and anticoagulant prescription within 30-days after discharge. Medication adherence was estimated using the proportion of days covered (PDC) at 1-year. PDC <0.80 was used to define non-adherence. A multivariable model adjusting for covariates was performed to identify the factors associated with non-adherence at 1-year. This analysis was restricted to new users of GDMT. Results: Among 155220 patients admitted with acute ischemic stroke during the study period, 15,919 met the inclusion criteria. The mean age was 55.7 years, and 7,701 (48.3%) were women. Women were less likely prescribed statins (58.0% vs 71.8%), and antihypertensives (27.7% vs 41.8%). In this subset of patients with atrial flutter/fibrillation, women were also less likely prescribed anticoagulants (41.2% vs 45.0%). Women were more likely to be non-adherent (i.e., PDC <0.80) to statins (47.3% vs 41.6%, P<0.0001), antihypertensives (33.3% vs 32.2%, P=0.005), and the combination of both (49.6% vs 45.0%, P=0.003). On multivariable analysis, women were likely to be non-adherent to GDMT at 1-year (odds ratio 1.23, 95% confidence interval 1.08-1.41). Conclusions: In this real-world analysis of commercially insured patients with ischemic stroke, women were less likely initiated on GDMT within 30 days after discharge. Women were more likely to be non-adherent to statins and antihypertensive agents at 1-year. Future efforts and novel interventions are needed to understand the reasons and minimize these disparities.

The Trial Enrollment Diversity Dashboard for Acute Leukemia Clinical Research: Intervention Development and Cohort Analysis.

PURPOSE: Participation in acute leukemia clinical trials is inequitable across multiple sociodemographic categories. Tools that provide researchers with performance feedback on the representativeness of the patients they enroll are limited. We aimed to develop an electronic health record (EHR)-based dashboard to provide such feedback and to describe any enrollment inequities uncovered. METHODS: We created a visual dashboard linking leukemia clinical trial registration and EHR data at the Dana-Farber Cancer Institute. Accuracy of a patient inclusion and assignment algorithm was tested with a target area under the receiver-operator curve (AUROC) of >0.90 against manual review. Demographic metric identification, visualization construction, and dashboard refinement were performed through stakeholder cognitive testing. Analysis of a recent 5-year cohort generated by the final algorithm assessed bivariate associations between enrollment and demographic metrics. Multivariable logistic regression included significant bivariate results. RESULTS: The final algorithm assignment AUROC was 0.98. Metrics were identified and visualizations successfully constructed. Fourteen individuals participated in testing and identified areas for revision: category mergers, denominator filters, and data delivery preferences. In the initial cohort of 1,315 patients, 1,020 (77.6%) had enrolled in any study protocol: 553 (42.1%) in a treatment trial and 936 (71.2%) in a biobanking study. In a multivariable model, older age (odds ratio [OR], 0.83 [95% CI, 0.73 to 0.94]) and Non-Hispanic Black race-ethnicity (OR, 0.38 [95% CI, 0.18 to 0.82]) were associated with lower enrollment, and English primary language with higher enrollment (OR, 2.50 [95% CI, 1.30 to 4.79]). CONCLUSION: We developed a research participation equity performance feedback dashboard for clinical researchers, and we identified actionable inequities. Next steps include feasibility and efficacy testing as well as implementation.

Lipid Organization by the Caveolin-1 Complex.

Caveolins are lipid-binding proteins that can organize membrane remodeling and oligomerize into the 8S-complex. The CAV1 8S-complex comprises a disk-like structure, about 15nm in diameter, with a central beta barrel. Further oligomerization of 8S-complexes remodels the membrane into caveolae vessels, with a dependence on cholesterol concentration. However, the molecular mechanisms behind membrane remodeling and cholesterol filtering are still not understood. Performing atomistic Molecular Dynamics simulations in combination with advanced sampling techniques, we describe how the CAV1-8S complex bends the membrane and accumulates cholesterol. Here, our simulations show an enhancing effect by the palmitoylations of CAV1, and we predict that the CAV1-8S complex can extract cholesterol molecules from the lipid bilayer and accommodate them in its beta barrel. Through backmapping to the all-atom level we also conclude that the Martini v2 coarse-grained forcefield overestimates membrane bending, as the atomistic simulations exhibit only very localized bending.

Light-field tomographic fluorescence lifetime imaging microscopy.

Fluorescence lifetime imaging microscopy (FLIM) is a powerful imaging technique that enables the visualization of biological samples at the molecular level by measuring the fluorescence decay rate of fluorescent probes. This provides critical information about molecular interactions, environmental changes, and localization within biological systems. However, creating high-resolution lifetime maps using conventional FLIM systems can be challenging, as it often requires extensive scanning that can significantly lengthen acquisition times. This issue is further compounded in three-dimensional (3D) imaging because it demands additional scanning along the depth axis. To tackle this challenge, we developed a computational imaging technique called light-field tomographic FLIM (LIFT-FLIM). Our approach allows for the acquisition of volumetric fluorescence lifetime images in a highly data-efficient manner, significantly reducing the number of scanning steps required compared to conventional point-scanning or line-scanning FLIM imagers. Moreover, LIFT-FLIM enables the measurement of high-dimensional data using low-dimensional detectors, which are typically low cost and feature a higher temporal bandwidth. We demonstrated LIFT-FLIM using a linear single-photon avalanche diode array on various biological systems, showcasing unparalleled single-photon detection sensitivity. Additionally, we expanded the functionality of our method to spectral FLIM and demonstrated its application in high-content multiplexed imaging of lung organoids. LIFT-FLIM has the potential to open up broad avenues in both basic and translational biomedical research.

Morphology of True Lumen and Surgical Outcomes of Acute Type A Aortic Dissection Repair with Superior Mesenteric Artery Malperfusion.

BACKGROUND: Acute type A aortic dissection (ATAD) can cause visceral malperfusion. Central aortic repair may resolve malperfusion but some require further intervention. This study aimed to review outcomes after ATAD presenting with visceral malperfusion and to evaluate the predictive value of true lumen (TL) morphologies in preoperative computed tomography (CT) for persistent superior mesenteric artery (SMA) ischemia after central repair. METHODS: Open surgical repair of ATAD performed between 2008-2023 at our institution was retrospectively reviewed. Patients with central repair first approach were included for analysis. Patients with inadequate CT scan data to assess luminal morphology were excluded. TL morphology was reviewed at the diaphragm level and categorized as concave or convex. The malperfusion pattern, static vs. dynamic, was assessed at SMA orifices. Data were analyzed using a contingency table and parametric and nonparametric methods. RESULTS: A total of 543 open ATAD repairs were performed. Of these, 263 patients were eligible under the inclusion criteria and, subsequently, analyzed. The mean age was 57±14, and 83 (31%) patients were female. SMA malperfusion developed in 42 (16%) of the 263 patients, including 26 patients with dynamic obstruction, 6 patients with static obstruction, and 10 patients with dynamic and static obstruction. Regarding dissection flap morphology, 78 patients (30%) exhibited concave morphology, while 185 patients (70%) had convex morphology. TL diameter was significantly larger in convex than concave (concave: 6 mm vs. convex: 16 mm, p<0.0001). The prevalence of clinically significant SMA malperfusion was higher in concave-shaped TL (concave 41% vs. convex 5%, p<0.0001). Dynamic SMA obstruction was more frequently observed in the concave group (concave 72% vs. convex 30%, P <0.001). However, significantly more patients with convex-shaped TL required bowel resection than concave (concave 13% vs. convex 70%, p<0.001). The operative mortality was higher in the convex group, although statistically insignificant (concave 19% vs. convex 50%, p=0.0059). CONCLUSION: Central repair first strategy could resolve more than 80% of SMA malperfusion in ATAD when the TL is concave-shaped at the level of the diaphragm. Convex-shaped TL morphology was associated with less incidence of SMA malperfusion but was more frequently associated with static obstruction and higher incidence of bowel resection. The morphology evaluation of the TL at the diaphragm level may be simple and beneficial for surgical planning for ATAD presenting with SMA malperfusion.

Comparative Assessment of Otolaryngology Knowledge Among Large Language Models.

OBJECTIVE: The purpose of this study was to evaluate the performance of advanced large language models from OpenAI (GPT-3.5 and GPT-4), Google (PaLM2 and MedPaLM), and an open source model from Meta (Llama3:70b) in answering clinical test multiple choice questions in the field of otolaryngology-head and neck surgery. METHODS: A dataset of 4566 otolaryngology questions was used; each model was provided a standardized prompt followed by a question. One hundred questions that were answered incorrectly by all models were further interrogated to gain insight into the causes of incorrect answers. RESULTS: GPT4 was the most accurate, correctly answering 3520 of 4566 questions (77.1%). MedPaLM correctly answered 3223 of 4566 (70.6%) questions, while llama3:70b, GPT3.5, and PaLM2 were correct on 3052 of 4566 (66.8%), 2672 of 4566 (58.5%), and 2583 of 4566 (56.5%) questions. Three hundred and sixty-nine questions were answered incorrectly by all models. Prompts to provide reasoning improved accuracy in all models: GPT4 changed from incorrect to correct answer 31% of the time, while GPT3.5, Llama3, PaLM2, and MedPaLM corrected their responses 25%, 18%, 19%, and 17% of the time, respectively. CONCLUSION: Large language models vary in their understanding of otolaryngology-specific clinical knowledge. OpenAI's GPT4 has a strong understanding of core concepts as well as detailed information in the field of otolaryngology. Its baseline understanding in this field makes it well-suited to serve in roles related to head and neck surgery education provided that the appropriate precautions are taken and potential limitations are understood. LEVEL OF EVIDENCE: N/A Laryngoscope, 2024.

Perspectives on the clinical use of anti-amyloid therapy for the treatment of Alzheimer's disease: Insights from the fields of cancer, rheumatology, and neurology.

Introduction: The advent of disease-modifying therapies for Alzheimer's disease (AD) has raised many questions and debates in the field as to the clinical benefits, risks, and costs of such therapies. The controversies have resulted in the perception that many clinicians are apprehensive about prescribing these medications to their patient populations. There also remains widespread uncertainty as to the economic impact, cost benefit ratio, and safety oversight for use of these medications in standard clinical care settings. Methods: To contextualize such issues, the present study compared anti-amyloid biologic therapy (lecanemab) to four commonly used biologic agents in other fields, including trastuzumab for breast cancer, bevacizumab for lung cancer, etanercept for rheumatoid arthritis, and ocrelizumab for multiple sclerosis. Results: The data presented demonstrate comparable costs, clinical benefits, and risks for these biologic agents in their disparate disease states. Discussion: These results provide context for the costs, clinical benefits, and safety regarding the mainstream use of anti-amyloid biologic agents for the prevention of cognitive loss. While the era of disease-modifying therapies for AD is now in its infancy, there is an expectation that these discoveries will be followed by improved therapies and combination treatments leading to greater efficacy in ameliorating the clinical trajectory of AD. Highlights: Anti-amyloid therapy costs are comparable to other commonly used biologics.Anti-amyloid therapy efficacy is comparable to other commonly used biologics.Anti-amyloid therapy safety is compatible with other commonly used biologics.

International Variation in Health Status Benefits in Patients Undergoing Initial Invasive Versus Conservative Management for Chronic Coronary Disease: Insights From the ISCHEMIA Trial.

BACKGROUND: The ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) demonstrated greater health status benefits with an initial invasive strategy, as compared with a conservative one, for patients with chronic coronary disease and moderate or severe ischemia. Whether these benefits vary globally is important to understand to support global adoption of the results. METHODS: We analyzed participants' disease-specific health status using the validated 7-item Seattle Angina Questionnaire (SAQ: >5-point differences are clinically important) at baseline and over 1-year follow-up across 37 countries in 6 international regions. The average effect of initial invasive versus conservative strategies on 1-year SAQ scores was estimated using Bayesian proportional odds regression and compared across regions. RESULTS: Considerable regional variation in baseline health status was observed among 4617 participants (mean age=64.4±9.5 years, 24% women), with the mean SAQ summary scores of 67.4±19.5 in Eastern Europe participants (17% of the total), 71.4±15.4 in Asia-Pacific (18%), 74.9±16.7 in Central and South America (10%), 75.5±19.5 in Western Europe (26%), and 78.6±19.2 in North America (28%). One-year improvements in SAQ scores were greater in regions with lower baseline scores with initial invasive management (17.7±20.9 in Eastern Europe and 11.4±19.3 in North America), but similar in the conservative arm. Adjusting for baseline SAQ scores, similar health status benefits of an initial invasive strategy on 1-year SAQ scores were observed (ranging from 2.38 points [95% CI, 0.04-4.50] in North America to 4.66 points [95% CI, 2.46-6.94] in Eastern Europe), with an 88.3% probability that the difference in benefit across regions was <5 points. CONCLUSIONS: In patients with chronic coronary disease and moderate or severe ischemia, initial invasive management was associated with a consistent health status benefit across regions, with modest regional variability, supporting the international generalizability of health status benefits from invasive management of chronic coronary disease. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.

Ultrafast His-Tagged Protein Purification.

This article details how to use a vortex fluidic device (VFD) to accelerate protein purification via immobilized metal affinity chromatography (IMAC). Building upon a previous report of VFD-based purification, we introduce a membrane insert to simplify the purification protocol and the resin recovery step. This new platform can be adapted to different types of IMAC resins and purification membranes. Proteins can be purified directly from clarified lysate, non-clarified lysate, and even non-lysed cultures without concerns of system clogging. Strong binding between the Ni2+ and the target protein's His6-tag effectively captures the target protein on IMAC resins or membranes placed in the VFD. Continuous flow of different solutions through the VFD allows dynamic binding, washing, and elution of the target protein. Furthermore, the system dramatically accelerates protein purification; a typical purification from cell lysate requires approximately 4 min. Herein, we demonstrate the single-step purification of two His6-tagged proteins from both clarified and non-clarified cell lysates without requiring batch binding. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Preparation of the resin-loaded membrane insert and the vortex fluidic device (VFD) setup prior to purification Basic Protocol 2: Purification of His6-tagged proteins using the VFD Alternate Protocol: VFD-mediated His6-tagged protein purification from non-clarified lysate Support Protocol: Preparation of chemically modified glass fiber membrane for VFD-mediated immobilized metal affinity chromatography purification.

TCF4 trinucleotide repeat expansions and UV irradiation increase susceptibility to ferroptosis in Fuchs endothelial corneal dystrophy.

Fuchs endothelial corneal dystrophy (FECD), the leading indication for corneal transplantation in the U.S., causes loss of corneal endothelial cells (CECs) and corneal edema leading to vision loss. FECD pathogenesis is linked to impaired response to oxidative stress and environmental ultraviolet A (UVA) exposure. Although UVA is known to cause nonapoptotic oxidative cell death resulting from iron-mediated lipid peroxidation, ferroptosis has not been characterized in FECD. We investigated the roles of genetic background and UVA exposure in causing CEC degeneration in FECD. Using ungenotyped FECD patient surgical samples, we found increased levels of cytosolic ferrous iron (Fe2+) and lipid peroxidation in end-stage diseased tissues compared with healthy controls. Using primary and immortalized cell cultures modeling the TCF4 intronic trinucleotide repeat expansion genotype, we found altered gene and protein expression involved in ferroptosis compared to controls including elevated levels of Fe2+, basal lipid peroxidation, and the ferroptosis-specific marker transferrin receptor 1. Increased cytosolic Fe2+ levels were detected after physiologically relevant doses of UVA exposure, indicating a role for ferroptosis in FECD disease progression. Cultured cells were more prone to ferroptosis induced by RSL3 and UVA than controls, indicating ferroptosis susceptibility is increased by both FECD genetic background and UVA. Finally, cell death was preventable after RSL3 induced ferroptosis using solubilized ubiquinol, indicating a role for anti-ferroptosis therapies in FECD. This investigation demonstrates that genetic background and UVA exposure contribute to iron-mediated lipid peroxidation and cell death in FECD, and provides the basis for future investigations of ferroptosis-mediated disease progression in FECD.

A research agenda to advance the study of implementation mechanisms.

BACKGROUND: Implementation science scholars have made significant progress identifying factors that enable or obstruct the implementation of evidence-based interventions, and testing strategies that may modify those factors. However, little research sheds light on how or why strategies work, in what contexts, and for whom. Studying implementation mechanisms-the processes responsible for change-is crucial for advancing the field of implementation science and enhancing its value in facilitating equitable policy and practice change. The Agency for Healthcare Research and Quality funded a conference series to achieve two aims: (1) develop a research agenda on implementation mechanisms, and (2) actively disseminate the research agenda to research, policy, and practice audiences. This article presents the resulting research agenda, including priorities and actions to encourage its execution. METHOD: Building on prior concept mapping work, in a semi-structured, 3-day, in-person working meeting, 23 US-based researchers used a modified nominal group process to generate priorities and actions for addressing challenges to studying implementation mechanisms. During each of the three 120-min sessions, small groups responded to the prompt: "What actions need to be taken to move this research forward?" The groups brainstormed actions, which were then shared with the full group and discussed with the support of facilitators trained in structured group processes. Facilitators grouped critical and novel ideas into themes. Attendees voted on six themes they prioritized to discuss in a fourth, 120-min session, during which small groups operationalized prioritized actions. Subsequently, all ideas were collated, combined, and revised for clarity by a subset of the authorship team. RESULTS: From this multistep process, 150 actions emerged across 10 priority areas, which together constitute the research agenda. Actions included discrete activities, projects, or products, and ways to shift how research is conducted to strengthen the study of implementation mechanisms. CONCLUSIONS: This research agenda elevates actions to guide the selection, design, and evaluation of implementation mechanisms. By delineating recommended actions to address the challenges of studying implementation mechanisms, this research agenda facilitates expanding the field of implementation science, beyond studying what works to how and why strategies work, in what contexts, for whom, and with which interventions.

Open LEARN: Open access linear accelerator education and augmented reality Navigator.

PURPOSE: To create an open-access Linear Accelerator Education and Augmented Reality Navigator (Open LEARN) via 3D printable objects and interactive augmented reality assets. METHODS: This study describes an augmented reality linear accelerator (linac) model accessible through a QR code and a smartphone to address the challenges of medical physics and radiation oncology trainees in low-to-middle-income countries. RESULTS: Major components of a generic linear accelerator are modeled as individual objects. These objects can be 3D printed for hands-on learning and used as interactive 3D assets within the augmented reality app. In the AR app, descriptions are displayed to navigate the components spatially and textually. Items modeled include the treatment couch, klystron, circulator, RF waveguides, electron gun, waveguide, beam steering assemblies, target, collimators, multi-leaf collimators, and imaging systems. The linear accelerator is rendered at nearly 100% of its actual size, allowing users to change magnification and view objects from different angles. CONCLUSIONS: The augmented reality linear accelerators and 3D-printed objects make these complex machines easily accessible with smartphones and 3D-printing technologies, facilitating education and training through physical and virtual interaction.

Characteristics and Outcomes of Operatively Treated Discoid Lateral Meniscus in Pediatric and Young Adult Patients: A Multicenter Study.

BACKGROUND: Discoid lateral meniscus (DLM) is the most common congenital abnormality of the meniscus. Tears are common; treatment is frequently not definitive, often requiring reoperation. PURPOSE: To report the clinical manifestations, physical characteristics, operative treatments and findings, complications, and reoperations of DLM in pediatric patients from multiple centers across North America. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Consecutive patients who underwent treatment for symptomatic DLM at 9 institutions between 2000 and 2020 were included. Patient data, presenting symptoms and signs, surgical findings, treatments rendered, and postoperative complications, including reoperation rates, were collected. Means with ranges and counts with proportions are reported for continuous and categorical variables, respectively, and comparisons were made using either the chi-square or Fisher exact test. RESULTS: In total, 784 patients (867 knees) were included with a mean age at diagnosis of 12 years (range, 1-22 years) and a mean follow-up of 22.6 months (range, 0-154 months). Common preoperative symptoms were locking (33%) and snapping (30%). At surgery, tears in the DLM were present in 647 knees (594 patients [76%]); 95 knees (11%) had multiple tears; and in 140 knees, tears extended into >1 zone. Tears, when present, were more common within the posterior horn (41%) or body (34%) than the anterior horn (25%). Peripheral rim instability was reported in 241 knees (28%). Significantly more knees had instability posteriorly (15%; P = .0004) and anteriorly (9%; P = .0013) than along the body (3%). Tear type was most commonly complex (38%) or horizontal (34%). A total of 358 knees in 333 patients with tears (42% of all patients) underwent repair (55% of knees with tears). A total of 175 complications were reported, occurring in 139 knees in 134 patients (17%); 116 of these knees with complications (83%) had a single complication, while 23 (17%) had >1. Of the 784 patients, 105 (13%) underwent reoperation, undergoing 135 additional procedures related to their DLM. Of those, 60 (44%) were repeat arthroscopy and meniscal trim; 40 (30%), arthroscopy and meniscal repair; and 17 (13%), an articular cartilage procedure. CONCLUSION: Locking and snapping were common presenting symptoms. Over three-quarters of patients had meniscal tears, which were most often complex and located posteriorly. Seventeen percent of patients experienced complications, and a sixth of patients with complications had >1. Reoperation was typically for persistent symptoms or meniscal retear.

Quantitative insights into the mechanism of proton conduction and selectivity for the human voltage-gated proton channel Hv1.

Human voltage-gated proton (hHv1) channels are crucial for regulating essential biological processes such as immune cell respiratory burst, sperm capacitation, and cancer cell migration. Despite the significant concentration difference between protons and other ions in physiological conditions, hHv1 demonstrates remarkable proton selectivity. Our calculations of single-proton, cation, and anion permeation free energy profiles quantitatively demonstrate that the proton selectivity of the wild-type channel originates from its strong proton affinity via the titration of the key residues D112 and D174, although the channel imposes similar kinetic blocking effects for protons compared to other ions. A two-proton knock-on model is proposed to mathematically explain the electrophysiological measurements of the pH-dependent proton conductance in the conductive state. Moreover, it is shown that the anion selectivity of the D112N mutant channel is tied to impaired proton transport and substantial anion leakage.

Play With Me: Effects of a shared activities parenting intervention on parenting and relative reinforcing value of food.

This pilot randomized controlled trial evaluated impacts of a novel shared activities intervention designed to promote positive parent-child interactions, which may function as an alternative reinforcer to food. The 4-week, at-home Play With Me intervention combines didactic parenting videos and play kits with materials for parent-child activities to practice skills. Aims of the present study were to examine the intervention's acceptability and its effects on parenting and the relative reinforcing value (RRV) of food versus parent-child activity at post-intervention. Thirty-two parents of 4-to-5-year-old children at risk for obesity were randomly assigned to the intervention or a waitlist control group. The intervention was well-liked by parents and feasible. Intervention parents reported more parenting structure and demonstrated higher observed sensitive parenting than controls at post; the latter finding was driven by greater parent positive mood, warmth, positive reinforcement, and relationship quality, with large effect sizes. There were no effects on the RRV of food. Inconsistent with hypotheses, there were trends toward control group parents reporting more parenting satisfaction and efficacy at post. Possible explanations are discussed. Results suggest Play With Me shows promise as an effective and acceptable intervention to promote positive parenting. Further research is needed to examine these effects and their implications for socioemotional development and health in a larger, more diverse sample over a longer time frame.

Virtual birefringence imaging and histological staining of amyloid deposits in label-free tissue using autofluorescence microscopy and deep learning.

Systemic amyloidosis involves the deposition of misfolded proteins in organs/tissues, leading to progressive organ dysfunction and failure. Congo red is the gold-standard chemical stain for visualizing amyloid deposits in tissue, showing birefringence under polarization microscopy. However, Congo red staining is tedious and costly to perform, and prone to false diagnoses due to variations in amyloid amount, staining quality and manual examination of tissue under a polarization microscope. We report virtual birefringence imaging and virtual Congo red staining of label-free human tissue to show that a single neural network can transform autofluorescence images of label-free tissue into brightfield and polarized microscopy images, matching their histochemically stained versions. Blind testing with quantitative metrics and pathologist evaluations on cardiac tissue showed that our virtually stained polarization and brightfield images highlight amyloid patterns in a consistent manner, mitigating challenges due to variations in chemical staining quality and manual imaging processes in the clinical workflow.