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Abstract Background The Movement Disorder Society (MDS) research criteria for possible prodromal multiple system atrophy (PP‐MSA) have not been prospectively validated. Objective To evaluate the diagnostic performance of the PP‐MSA criteria in a longitudinal cohort of patients with pure autonomic failure (PAF) and to assess whether additional clinical features improve their predictive value. Methods Seventy‐six patients with PAF enrolled across eight centers in the Natural History Study of the Synucleinopathies were followed for ≥6 years or until phenoconversion. Participants were classified according to MDS PP‐MSA criteria and followed for development of MSA, Parkinson's disease, or dementia with Lewy bodies. Diagnostic performance was assessed longitudinally. Analyses were repeated using a stricter olfactory threshold (University of Pennsylvania Smell Identification Test [UPSIT]≤28) as an exclusion criterion. Results Thirty‐eight participants met PP‐MSA criteria, of whom 12 phenoconverted to MSA within 6 years. Sensitivity was 100% at year 1 and 92% at year 6, whereas specificity ranged from 56% to 67%. Positive predictive value (PPV) ranged from 21% to 34%. Applying a stricter olfactory threshold improved specificity (90%–97%) and PPV (53%–83%), with a modest reduction in sensitivity (to 83%). Participants who phenoconverted to MSA were younger, had more severe urinary dysfunction, and greater orthostatic heart rate responses. Conclusions The PP‐MSA criteria demonstrate high sensitivity but limited specificity in patients with PAF. A stricter olfactory threshold improves diagnostic performance and may enhance cohort enrichment for clinical trials. © 2026 International Parkinson and Movement Disorder Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Introduction The nerve-derived growth factor neuregulin (NRG) plays a role in the regulation of skeletal muscle mass through Akt and mTOR signaling transduction pathways that regulate both protein synthesis and degradation. We previously reported that NRG increases muscle protein synthesis (~20%) in a PI3 kinase (PI3K)/Akt-dependent manner. However, the effects of NRG on protein degradation are still poorly understood and are needed to elucidate the role of NRG in the maintenance of skeletal muscle protein balance. Methods Neonatal diaphragm muscle ex vivo preparations were pharmacologically treated with NRG and pharmacological inhibitors of PI3K (LY294002, 50 μM), MEK (PD98059, 50 μM) or mTOR (rapamycin, 100 nM). Tyrosine release from muscle was used as a surrogate measure of protein degradation. Results We report that basal protein degradation in the neonatal rat diaphragm muscle is significantly reduced by NRG treatment (19%). Basal protein degradation was increased following treatment with inhibitors of PI3K, MEK or mTOR, with inhibition of each pathway sufficient to increase basal protein degradation greater than 30%. Importantly, NRG treatment in the presence of each of these inhibitors blunts the increase in protein degradation induced by inhibition of PI3K, MEK or mTOR. NRG effects were significantly blunted by rapamycin (p < 0.05 compared to NRG alone), but not by LY294002 or PD98059. Discussion We suggest that both the PI3K/Akt and MAP kinase pathways are important for NRG effects on protein degradation, but that mTOR may be a critical modulator of these effects and thus of protein balance in skeletal muscle.

Most patients with chest pain do not have acute myocardial infarction (AMI), yet post-AMI rule-out disposition remains variable. Detectable but sub-99th percentile high-sensitivity cardiac troponin I (hs-cTnI) provides additional prognostic information. We evaluated the economic value of hs-cTnI-guided hospitalizations among non-AMI patients. We analyzed 1481 non-AMI chest pain visits with detectable baseline hs-cTnI across 29 U.S. emergency departments (2014–2016) in the prospective HIGH-US trial using the Atellica IM TnIH assay(Siemens Healthcare Diagnostics, Tarrytown, NY, US). We compared observed standard-of-care admissions with modeled pathways incorporating hs-cTnI thresholds and risk scores, assessing admission rates, costs, and diagnostic accuracy for 30-day death/MI. Overall, 1.0% (n = 15/1481) experienced 30-day death/MI. Standard-of-care admitted 59% of patients with 93% sensitivity and 41% specificity. The modeled pathway using hs-cTnI ≥ 5 ng/L plus non-low risk scores was associated with reduced projected admission of 41%, higher specificity of 60%, and the same 93% sensitivity. Estimated per-patient diagnostic costs were lower under Scenario 1 (noninvasive diagnostic testing only; $1025 vs. $1139) and under Scenario 2 (including inpatient/invasive procedures; $2672 vs. $3536). In subgroups, higher hs-cTnI thresholds conferred further economic benefit without compromising sensitivity. Incorporating sub-99th percentile hs-cTnI thresholds alongside risk scores may support more efficient resource use while maintaining safety, although findings require prospective validation.

Background and Objectives: The Middle East and North Africa (MENA) region has one of the highest age-standardized diabetes prevalence rates globally, yet all-age, diabetes-specific evidence incorporating GBD 2023 estimates through 2023 remains limited. Materials and Methods: Using Global Burden of Disease (GBD) 2023 estimates for 21 MENA countries from 1990 to 2023, this ecological time-trend analysis quantified 33-year trends in incidence, prevalence, mortality, and disability-adjusted life-years (DALYs); compared pre-2019 and post-2019 trajectories using joinpoint regression; characterized age- and sex-specific burden patterns; and quantified contributions of modifiable risk factors. Results: Age-standardized incidence increased 92%, from 251.7 (95% uncertainty interval [UI]: 231.5 to 272.4) to 482.5 (95% UI: 451.5 to 516.4) per 100,000, and prevalence more than doubled, from 5564 (95% UI: 5088 to 6024) to 11,247 (95% UI: 10,382 to 12,132) per 100,000. In 2023, males exhibited higher DALY rates than females in most adult age groups from age 15 years onward, shifting away from the female-predominant pattern seen in 1990; female rates remained higher at several of the oldest age groups. Children aged 0 to 14 years were the only group with declining DALY rates (−52% to −57%). Post-2019 incidence was higher in 15 of 21 countries, and six countries had higher DALY trends with non-overlapping confidence intervals. Because we only have four to five years of data, these short trends are preliminary and require care when evaluating. High body-mass index was the leading modifiable risk factor. Conclusions: These data support country-specific prevention and chronic-care strategies across the MENA region.

Exposure of airway epithelia to environmental allergens or nanoparticles invokes a novel genome-protective physiological response to oxidative stress. Fragments of double-stranded genomic DNA released into the airway lumen originate from repetitive, transcriptionally active, and fragile sites within the genome. Exporting DNA with high repetitive content potentially aids cell survival through the preservation of genome integrity and fidelity during the repair process.

ABSTRACT Background Diagnostic interpretation of kidney allograft biopsies using the Banff classification remains variable, but the determinants of this variability are not fully defined. We performed a global, fully digital multi-reader study to identify the principal drivers of disagreement in Banff-based assessment. Methods Thirty-six kidney transplant biopsies were independently scored by 67 renal pathologists on a standardized digital platform. Readers assessed Banff lesions on hematoxylin and eosin, periodic acid–Schiff, and Jones’ silver stains; final diagnostic categories were assigned using prespecified Banff-based decision rules. Interobserver agreement was quantified with Gwet’s agreement coefficient (AC) statistics. Determinants of diagnostic agreement were evaluated using pairwise mixed-effects logistic regression, and reader similarity was examined by principal component analysis (PCA) with post hoc molecular annotation. Results Agreement for final diagnostic categories was moderate (Gwet’s AC1, 0.55; 95% CI, 0.47–0.63). Lesion-level agreement varied substantially, with lowest agreement for selected threshold-dependent inflammatory or semi-quantitative lesions, including interstitial inflammation in areas of IFTA, peritubular capillaritis and arteriolar hyalinosis. Diagnostic concordance differed markedly across biopsies, indicating strong case-level heterogeneity. In pairwise models, differences in active inflammatory and vascular lesion scoring were the strongest correlates of diagnostic disagreement; reader experience and geography contributed minimally. Principal component analysis showed reader variation was organized along two dominant axes: a rejection-calling threshold axis linked mainly to tubulointerstitial inflammatory injury, and a T cell-mediated (TCMR/TI) and antibody-mediated/microvascular (AMR/MVI) inflammation-oriented phenotypic classification axis. Conclusion Interobserver variation in Banff-based kidney transplant biopsy assessment is structured rather than random and driven mainly by how readers threshold and integrate key inflammatory lesion compartments rather than experience or geographic location.

Background: Greater trochanteric (GT) fractures after total hip arthroplasty (THA) are typically managed nonoperatively. However, outcome data for patient counseling remain limited. We evaluated the nonoperative results, focusing on fracture union rates and the presence of persistent limp in relation with fracture location, displacement magnitude, and direction. Methods: We retrospectively reviewed 82 postoperative GT fractures not associated with trochanteric osteolysis following primary THA performed between 1984 and 2020. The mean follow-up was 9 years. Fracture location was classified relative to the contralateral lesser trochanter as tip, waist, or base. Initial displacement, migration, final displacement, and bony union were assessed radiographically. Clinical outcomes included the presence of a persistent limp and Harris Hip Score. Multivariable analyses were performed to identify factors associated with nonunion and limp. Results: Fractures were classified as tip (n = 32), waist (n = 29), or base (n = 21). The mean initial displacement was 8.9 mm, with 43% displaced >10 mm. Initial displacement was significantly lower in base fractures (4.8 mm) compared with tip (10.1 mm) or waist (10.8 mm) fractures (p < 0.05). The mean final displacement was 14.6 mm. 45% of fractures achieved complete bony union, and 38% of patients demonstrated a persistent limp. In multivariable analysis, greater final displacement (>12 mm), and tip and waist fractures were independently associated with nonunion. Posterior fracture displacement was significantly associated with persistent limp. Conclusions: Outcomes following nonoperative management of GT fractures after THA depend on fracture morphology and displacement characteristics. Tip and waist fractures and fractures with final displacement >12 mm have a higher risk of nonunion, whereas posterior and superior displacement is associated with persistent limp. Greater than 20 mm of displacement is associated with both limp and nonunion. These findings may assist surgeons in counseling patients and in identifying fracture patterns at higher risk for adverse outcomes of nonoperative management. Level of Evidence: Level III (Prognostic Study). See Instructions for Authors for a complete description of levels of evidence.