Citations

Abstract Background An accurate discrete spot scanning (DSS) beam delivery time (BDT) model is essential, particularly as 4D dynamic dose accumulation calculations rely on machine‐specific time models for reliable interplay evaluation. Purpose To derive a BDT model for a synchrotron‐based Hitachi Probeat PBS proton system from oscilloscope measurements of key BDT structures, including multi‐energy extraction (MEE) characteristics. Methods Key BDT structures were characterized using oscilloscope measurements, supplemented by delivery log files where appropriate. Spot‐to‐spot scanning trajectories were visualized using a CROSSmini 2D strip ionization chamber (Liverage Biomedical Inc, Taiwan) via the dose‐driven continuous scanning (DDCS) mode. The MEE design and MEE charge recapture efficiencies were also characterized. In addition, the impact of the number of delivered spots on both the extractable fraction of charge and MEE recapture efficiency was investigated. Results An improved synchrotron‐based BDT model was derived that incorporates dead times between radiofrequency knockout (RFK) and high‐speed steering magnet (HSST) signals. Spot‐to‐spot movement follows a “hockey‐stick”‐like behavior where the effective spot‐to‐spot move time is governed by the slower axis. An energy‐dependent variation in the number of MEE layers deliverable per spill was also observed, with fewer MEE layers per spill (1–3) was observed in low and high energy ranges compared to the mid‐energy range (4–5), deviating from the nominal vendor value of five MEE layers per spill per block. A reduction in the extractable fraction of charge was observed with an increasing number of spots per spill, while increasing the number of delivered spots in the preceding layer significantly reduced the MEE recapture efficiency. Conclusion MEE characteristics should be incorporated into synchrotron‐based time models for accurate beam delivery modeling. The methodology presented here also provides a framework for centers seeking to derive machine‐specific delivery time models for their proton systems.

Abstract Inflammatory bowel diseases (IBD), principally Crohn’s disease (CD) and ulcerative colitis (UC), are common chronic disorders involving inflammation and often progressive tissue damage. Genome-wide association studies have mapped many risk signals, but the causal variants, effector genes and relevant cellular contexts remain difficult to resolve, limiting mechanistic interpretation and therapeutic translation. Here we performed a multi-ancestry GWAS meta-analysis of 125,992 individuals with IBD and more than 1.2 million controls, identifying 619 independent association signals (374 novel) at 420 IBD regions that account for 77–80% of SNP-based heritability. Fine-mapping resolved 81 high-confidence variants, 41 not previously reported. Although most signals were shared between CD and UC, 39% showed IBD subtype specificity, with UC signals showing stronger enrichment in functional annotations from intestinal epithelial, secretory and enteroendocrine cells, and CD showing stronger genetic correlations with circulating inflammatory biomarkers, including C-reactive protein and glycoprotein acetylation. Latent causal modelling supported a causal effect of decreased high-density lipoprotein on CD risk. By integrating bulk and single-cell eQTL and pQTL resources using colocalisation and Mendelian randomisation, together with coding-variant evidence from exome sequencing, we prioritised 664 candidate effector genes across 341 signals, including 390 newly implicated IBD genes, revealing new biological mechanisms and candidate therapeutic targets supported by human genetics.

Importance Transcatheter tricuspid valve replacement (TTVR) demonstrated superior outcomes over medical therapy in patients with severe tricuspid regurgitation (TR) in the Edwards EVOQUE Transcatheter Tricuspid Valve Replacement: Pivotal Clinical Investigation of Safety and Clinical Efficacy Using a Novel Device II (TRISCEND II) randomized clinical trial, and received regulatory approval in the US in 2024. Contemporary real-world data on its effectiveness and safety remain limited. Objective To evaluate 30-day clinical, echocardiographic, and health status outcomes of TTVR in real-world use. Design, Setting, and Population Retrospective cohort study of all consecutive patients who underwent TTVR in the US from February 2024 through March 2025 in the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry. Patients had symptomatic, severe TR despite optimal medical therapy and TTVR was deemed appropriate by a heart team. Statistical analysis was conducted from September 2025 to February 2026. Exposure Device-enabled TTVR. Main Outcomes and Measures Thirty-day event rates (all-cause death, stroke, bleeding, new cardiac implantable electronic device [CIED] implantation, heart failure hospitalizations), TR reduction, and changes in health status (New York Heart Association [NYHA] functional class and Kansas City Cardiomyopathy Questionnaire Overall Summary [KCCQ-OS] score) are reported. Subgroup analyses examined the impact of baseline CIED status on outcomes. Results Among 1034 attempted procedures at 82 centers (mean [SD] age, 77.1 [10.6] years; 69.1% female; 73.2% NYHA functional class III/IV), a valve was successfully implanted in 1017 patients (98.4%). Mild or less TR was achieved in 98.4% of patients post procedure and in 97.7% at 30 days. At 30 days, all-cause mortality was 3.1%; stroke, 0.2%; bleeding, 7.9%; new CIED, 15.9% in CIED-naive patients; and heart failure hospitalization, 3.1%. There were significant improvements in NYHA functional class (class I/II, 82.7%; P < .001) and mean KCCQ-OS score (22.4 points; P < .001) from baseline to 30 days. There were no significant differences in 30-day mortality ( P = .47), heart failure hospitalization ( P > .99), and functional outcomes ( P = .55) when patients were stratified by baseline CIED status. Conclusions and Relevance Early US real-world experience with TTVR confirms safety and effectiveness in patients with severe TR. Thirty-day outcomes are consistent with the TRISCEND II pivotal trial, demonstrating acceptable safety, near-complete TR elimination, and significant health status improvements in an older, comorbid population. Rates of new CIED implantation and bleeding were lower than randomized clinical trial experience.

Abstract Eosinophils play an important role in mediating itch and inflammation in dermatitis. The role of the eosinophil granule protein eosinophil peroxidase (EPX) in mediating inflammation and itch was tested in a dermatitis mouse model. Mice were sensitized to trimellitic anhydride (TMA) and subsequently challenged chronically on the ear to establish dermatitis. Loss of EPX (in EPX−/− mice) or blocking EPX with the drug resorcinol significantly reduced dermatitis in mice exposed to TMA. Resorcinol also reduced levels of thymic stromal lymphopoietin protein (TSLP) in skin. Further studies showed that EPX increased different cytokines in keratinocytes in cell culture via 2 distinct mechanisms. EPX-induced TSLP expression requires lysophosphatidic acid signaling while EPX-induced expression of TNF-α, CSF2, CSF3, and IL1a required IL-1 signaling. We also showed that blocking IL-1 reduced inflammation in skin following TMA exposure in mice. Thus, EPX is an important mediator of inflammation and itch, that are mediated via at least 2 pathways. This suggests that both EPX and its signaling pathways may provide novel therapeutic strategies in dermatitis.

Abstract Background Dose‐driven continuous scanning (DDCS) is a type of beam delivery in Hitachi pencil beam scanning (PBS) particle therapy system. Particle beam is irradiated continuously between spots to achieve a higher effective dose rate and a shorter beam delivery time. The beam is only turned off at break spots, the end of a treatment layer and during spill change. The break spot is a unique feature of the DDCS introduced by the treatment planning system (TPS) to interrupt continuous scanning. DDCS separates the dose delivery of a spot into a move dose and stop dose components. The move dose is controlled by the scanning speed and beam current, while the stop dose delivers the remaining monitor units (MUs). Hence, rigorous quality assurance (QA) of the scanning speed and functionality of break spot are required to ensure safe and successful DDCS delivery. Purpose We aim to report for the first time the QA methodology and result for DDCS, focusing on the scanning speed and break spot validation. Methods A rectangular spiral irradiation pattern with different degree of break spots were irradiated on a 2D strip ionization chamber (CROSSmini) detector using 50 time resolution to validate the break spots. Four methods of measuring scanning speeds were proposed. Using a spiral irradiation pattern, methods one and two applied linear regression to the scanning time measured by the CROSSmini for different inter‐spot distances, with measurements taken at sampling rates of 5 and 20 kHz, respectively. Methods three and four measured the scanning time of single inter‐spot distances in the X and Y directions. Method three measured the scanning time with the CROSSmini while method four measured the rise and fall time of the scanning magnet (SCM) current. All measurements were performed with 70.2, 150.2 and 228.7 MeV proton beam energies and three different beam currents of 8, 14 and 20 MU/s. Lastly, the scanning speed tolerance limit was calculated analytically under the requirement of avoiding a beam abort when the stop dose was less than zero. Results The data recorded by the CROSSmini under the spiral irradiation patterns with break spots was reconstructed into a 2D dose, and the break spots’ operations were visually validated for all the energies and beam currents. There were no statistically significant difference in the measured X and Y scanning speeds across the four methods. However, the last method involving the SCM current yielded the largest type A uncertainty of up to 25% () due to the noisy signal. The first method with the linear regression and 5 kHz acquisition rate was preferred due to a smaller type A uncertainty of up to 2.0% and a lower false negative rate in detecting the rising and falling edges during scanning. The calculated tolerance limit based on our current DDCS setting was found to be 0.50 times of the expected scanning speed. Conclusion We have introduced QA protocols for DDCS, designed to ensure complete and safe beam delivery without interruptions caused by move doses exceeding planned spot doses.

Abstract INTRODUCTION: Pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis (PVOD/PCH) is a rare subgroup of pulmonary arterial hypertension (PAH). Unfortunately, there is significant overlap between PVOD and PAH, making differentiation difficult. Thus, a constellation of investigations is necessary to suggest such a diagnosis. CASE PRESENTATION: A 65-year-old female with a history of smoking was diagnosed with idiopathic PAH following 2 months of worsening dyspnea. Right heart catheterization (RHC) revealed a mean PA pressure (mPAP) 58mmHg, pulmonary artery wedge pressure (PAWP) 14mmHg, cardiac output/index (CO/CI) 5.5/2.6, and pulmonary vascular resistance (PVR) 8 Wood units. Further workup excluded other causes of pulmonary hypertension (Table 1). Tadalafil was initially started followed by macitentan, which were associated with worsening hypoxemia and dyspnea. Computed tomography (CT) scan of the chest revealed mediastinal lymphadenopathy and small bilateral pleural effusions. This development in relation to the initiation of PAH-directed therapies raised concern for possible PVOD. Medical therapy was downtitrated, but worsening hypoxemia in the setting of worsening edema led to the cessation of all therapies. Due to clinical concern, the patient was admitted for a repeat RHC and close supervision during a trial of epoprostenol. RHC revealed a mPAP of 57mmHg, PAWP 5mmHg, CO/CI 3.4/1.6 and PVR 15 Wood units. She had been on metoprolol for hypertension which was discontinued. Low-dose epoprostenol was started at 1ng/kg/min. Her oxygen requirements increased slightly which improved with diuresis. Epoprostenol was slowly titrated with improvements in CI. Repeat chest CT showed mild diffuse centrilobular nodular opacities more prominent compared to prior scans, and adenopathy. After a steady dose of epoprostenol (4ng/kg/min), the patient improved with lower oxygen requirements. She was discharged with plans to continue low dose outpatient epoprostenol and start sotatercept. Lung transplant evaluation is on hold pending response to this approach. Genetic testing is pending. DISCUSSION: Despite challenges of definitive diagnosis where lung biopsy is risky, a diagnosis of PVOD can be supported from a spectrum of strongly suggestive clinical, hemodynamic and radiographic features. Though genetic testing for the EIF2AK4 mutation may confirm the presence of heritable PVOD, its absence does not exclude its possibility as most cases do not have an identifiable genetic cause. Management is challenging given ineffective or potentially harmful responses to PAH-directed therapies, though some do respond to a variable extent. As suggested here, close supervision during epoprostenol infusion adds to the limited body of evidence supporting such endeavors when initiating vasodilatory therapies in patients with suspected PVOD.

Background: There are limited evidence-based guidelines to predict which osteochondritis dissecans (OCD) lesions will heal with nonoperative treatment. Purpose: To train a set of classification algorithms to predict nonoperative OCD healing while identifying new clinically meaningful predictors. Study Design: Case-control study; Level of evidence, 3. Methods: Patients with OCD of the knee with open physes undergoing nonoperative management were prospectively queried from the Research on OCD of the Knee (ROCK) cohort ( https://kneeocd.org ) in April 2022. Patients were included if they met the study criteria for nonoperative treatment success or failure. Nonoperative treatment success was defined as complete healing on magnetic resonance imaging (MRI) and total return to sports participation. Failure was defined as the crossover from nonoperative management to surgery at any point at or beyond the 3-month follow-up. If a patient did not meet one of these criteria, they were not included. Normalized lesion size, lesion location, patient characteristics, and symptoms were used as clinically relevant predictors. Results: A total of 64 patients were included, of whom 24 (37.5%) patients successfully healed with nonoperative management. Multivariate logistic regression revealed that a 1% increase in normalized lesion width was associated with an increase in the likelihood of nonoperative failure (odds ratio [OR], 1.41 [95% CI, 1.17-1.81]; P < .01). By contrast, lesions in the posterior sagittal zone (OR, 0.08 [95% CI, 0.009-0.43]; P < .01) or the medial-most coronal zone (for lesions of the medial femoral) and lateral-most coronal zone (for lesions of the lateral femoral condyle) on MRI (OR, 0.05 [95% CI, 0.004-0.44]; P < .01) were associated with a decrease in the likelihood of nonoperative treatment failure. Support vector machines had a cross-validated area under the receiver operating characteristic curve of 0.89 and a classification accuracy of 83.3%. Conclusion: Lesion location in the posterior aspect of the condyle on sagittal MRI and lesion location in the medial-most or lateral-most locations on coronal MRI were identified as statistically significant predictors of increased nonoperative treatment success on multivariate analysis. Machine learning models can predict which OCD lesions will heal with nonoperative management with superior accuracy compared with previously published models.

Abstract Introduction . Dispersion in an accelerator quantifies the deviation of the proton trajectory when there is a momentum deviation. We present for the first time a safe method of measuring dispersion in the clinic, using a scintillator detector and the momentum deviations within a spill. This is an important accelerator quantity as we found that this is the reason behind the large dose fluctuation in our absolute dosimetry measurement. Methods . Dispersions are measured for nine energies in a Hitachi ProBeat system at three locations (isocenter and at two profile monitors) and at two gantry angles (0 and 90 degrees) by first measuring the spot position and momentum drift within a spill. The spot position drift is measured by the XRV-4000 at the isocenter, and by the two profile monitors located at 0.57 and 2.27 m from the isocenter. The momentum drift is calculated from the intra-spill range drift which is measured using the Ranger accessory. The dispersion at isocenter and its gradient are calculated using the weighted least square regression on the measured dispersions at the three locations. A constraint is formulated on the dispersion and its gradient to ensure minimal intra-spill spot position deviation around the isocenter. Results . The measured intra-spill range and spot positional drift at isocenter are less than 0.25 mm and 0.7 mm respectively. The momentum spread calculated from the range drift are less than 0.08%. The dispersion at the isocenter ranged from 0.50 to 4.30 m and the zero-crossing happens upstream of isocenter for all energies. 2 of the 9 energies (168.0 and 187.5 MeV) violated the constraint and has an intra-spill spot positional deviation greater than 1.0 within 5 cm from the isocenter. Conclusion . This measurement is recommended as part of commissioning and annual quality assurance for accelerator monitoring and to ensure intra-spill spot deviations remain low.