American Journal of Physiology-Lung Cellular and Molecular Physiology

Inadequate autophagy promotes smoking-induced cellular senescence involved in chronic obstructive pulmonary disease (COPD) pathogenesis. Transcription factor EB (TFEB) is a master regulator of the autophagy-lysosome axis. For the first time, we investigated the therapeutic potential of pemafibrate, a putative TFEB inducer. COPD lung epithelial cells showed reduced TFEB expression. Pemafibrate enhanced autophagy/mitophagy flux and restored lysosomal acidification observed during cigarette smoke (CS) extract exposure in human bronchial epithelial cells, resulting in reduced cellular senescence. TFEB knockdown demonstrated involvement of pemafibrate-induced TFEB in these effects. Pemafibrate induced TFEB expression, mitigated alveolar enlargement and airflow obstruction, and attenuated the CS-induced increase in static lung compliance in a long-term CS-exposed mouse model. It reduced the CS exposure-induced cellular senescence, possibly through autophagy/mitophagy, as suggested by bulk RNA sequencing of mouse lungs. A retrospective cohort study showed that patients given pemafibrate displayed attenuated FEV1.0 decline compared with those given bezafibrate or fenofibrate. In conclusion, pemafibrate is a promising therapeutic agent for COPD, potentially exerting its effects through the regulation of the TFEB-autophagy/mitophagy-lysosome axis.

Current approaches for imaging fibrotic remodeling have sensitivity, specificity and cost drawbacks that limit both preclinical research and clinical diagnosis. Here, we show that fast green FCF, a small molecule that binds to fibrillar collagen, enables highly sensitive and specific imaging of fibrosis in lung samples from mice and humans using fluorescence microscopy. We report strategies for using fast green FCF staining to assess fibrotic remodeling using precision-cut lung slice and whole-biopsy preparations. Our findings demonstrate that fluorescence imaging of fast green FCF-stained collagen will be useful for fibrosis research and may help to improve detection of fibrosis in clinical pathology.

Rationale: Pulmonary hypertension is defined by pulmonary hemodynamics, but diagnostic and prognostic biomarkers remain limited. Nuclear magnetic resonance (NMR) spectroscopy provides detailed insights, particularly in the lipid metabolism. Objectives: To explore circulating NMR-derived metabolites and lipoprotein-related parameters for their association with pulmonary hemodynamics and to analyse their prognostic properties in pulmonary arterial hypertension (PAH). Methods: Retrospective analysis of a PAH cohort with complete diagnostic workup including right heart catheterization and baseline serum samples, from the prospective GRaz Pulmonary Hypertension-Metabolism (GRAPH-M) registry. Measurements: NMR-derived metabolites and lipoprotein-related parameters were analyzed for their association with clinically relevant parameters of PAH. We defined PHIHDL, a score derived from high-density lipoprotein (HDL) related measures based on their strong association with pulmonary hemodynamics, and evaluated its prognostic value. Results: We included 100 patients with PAH treated at the PH clinic of LKH University Hospital, Medical University of Graz, between 2011 and 2021. Age was 61{+/-}15 years, female/male ratio 2.5, BMI 26 {+/-}7 kg/m2, mPAP 41{+/-}16 mmHg, PAWP 8.8{+/-}3.2 mmHg, PVR 8.0{+/-}4.9 WU, and median survival was 8.0 years. During follow-up, 46 patients died. We identified a cluster of 12 HDL-related measures that showed significant inverse association to pulmonary hemodynamics and derived PHIHDL from the reversed scaled average of these particles. PHIHDL was associated with all-cause mortality after adjustment for age and sex (HR 2.96, 95% CI 1.52-5.70), independent of the clinical risk scores COMPERA 2.0 and REVEAL Lite2. Conclusion: PHIHDL, a pulmonary hemodynamics-based metabolomic score, provides independent prognostic information beyond established risk scores in PAH.

Objective White smoke inhalation injury (WSI) causes severe acute lung damage with no specific therapy currently available. Sphingolipid metabolism is implicated in pulmonary inflammation, but its transcriptional regulatory landscape in WSI remains unexplored. This study aimed to identify key sphingolipid metabolism related genes and evaluate their regulatory roles and therapeutic potential in WSI. Methods We established a rat model of WSI and performed integrated bulk RNA sequencing, weighted gene coexpression network analysis (WGCNA), and single-cell RNA sequencing (scRNAseq) to screen for differentially expressed sphingolipid metabolism-related genes (DESRGs). Protein-protein interaction (PPI) network with four centrality algorithms was used to prioritize hub genes. In silico gene knockout and molecular docking were conducted to assess regulatory functions and identify potential drug candidates. Results We identified 22 DESRGs that were predominantly enriched in DNA replication and cell cycle pathways rather than canonical sphingolipid metabolic processes. PPI consensus prioritized three hub genes--Top2a, Ttk, and Ccna2--with Top2a exhibiting the highest expression in epithelial cells and significant downregulation after smoke exposure. ScRNAseq revealed immune cell infiltration and epithelial differentiation trajectories. Virtual knockout showed that Top2a depletion affected the largest transcriptomic fraction (~0.4%) and was enriched in lysosome biogenesis, innate immunity, phagocytosis, and lipid catabolism. Molecular docking identified thalidomide as a high affinity ligand for Top2a (Vina score: -8.5 kcal/mol). Conclusion Our multiomics integrative framework identifies Top2a as a central regulatory hub linking sphingolipid associated inflammation to epithelial responses in WSI, and nominates thalidomide as a potential drug repurposing candidate. These findings provide prioritized targets for future translational investigation.

Background: Cardiometabolic diseases frequently involve concurrent cardiovascular and hepatic dysfunction, yet the conserved molecular mechanisms underlying these systemic responses remain poorly defined. Objectives: To identify conserved molecular responses across complementary manifestations of cardiometabolic stress and determine whether integrated multi-organ analyses reveal therapeutically actionable targets for heart failure. Methods: Cardiac functional phenotyping, hepatic injury profiling, and bulk RNA sequencing were performed across three complementary mouse models representing distinct manifestations of cardiometabolic stress: high-fat diet plus L-NAME (HFD+LN)-induced heart failure with preserved ejection fraction (HFpEF; cardiovascular disease), Western diet (WD)-induced obesity (systemic metabolic stress), and choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD)-induced steatotic liver disease (hepatic metabolic stress). Comparative transcriptomic analyses distinguished organ-specific responses from conserved molecular signatures. Results: Each model produced distinct systemic, hepatic, and cardiac phenotypes accompanied by divergent transcriptional responses within individual organs. Cross-model and cross-organ integration identified a limited set of conserved molecular responses to cardiometabolic stress, with Serpine1, encoding plasminogen activator inhibitor-1 (PAI-1), emerging as a highly conserved candidate that exhibited preferential induction in the heart. Pharmacologic inhibition of PAI-1 significantly improved cardiac function and attenuated adverse remodeling in established HFpEF, whereas hepatic pathology was comparatively less affected, indicating differential organ-specific dependence on this pathway. Conclusions: Integrated analyses across complementary manifestations of cardiometabolic stress identified conserved molecular signatures that transcend individual disease models and organs. These findings establish a comparative framework for discovering cardiovascular therapeutic targets and identify PAI-1 as a promising mediator of cardiac remodeling in cardiometabolic disease.

Background: Transplant arterial injury is an underlying feature of acute organ transplant rejection and is a main cause of late heart transplant failure. The role of the gut microbiota, and especially specific microbial components of this community, in controlling immune responses that cause this aspect of rejection is poorly understood. Methods: We utilized a murine aortic interposition model of transplant arterial injury to investigate the role of the gut commensal bacteria, Akkermansia muciniphila, in controlling immune responses in transplant arteries. Results: Early life treatment of female mice with broad spectrum antibiotics, which delayed colonization of the intestinal tract with bacteria until after weaning, led to the development of dysbiosis in adults that was characterized by the absence of A. muciniphila. This was related to an elevation in systemic levels of CCL2 and a reduction in the immunomodulatory short-chain fatty acid, propionate. When transplant arterial injury was examined, there was more arterial injury indicative of acute rejection and increased intimal thickening reflective of transplant arteriosclerosis in grafts from dysbiotic mice compared to controls. Dysbiosis also increased macrophage accumulation early after transplantation in dysbiotic mice. Notably, restoring A. muciniphila in the gut microbiota of dysbiotic mice through voluntary oral administration in infants ameliorated macrophage-mediated transplant arterial injury. Conclusions: A. muciniphila is an immunomodulatory component of the gut microbiota that protects against vascular injury and pathology in organ transplantation.

Endothelial dysfunction is a hallmark of numerous vascular pathologies and is strongly influenced by mechanobiological forces within the vascular microenvironment. While the effects of shear stress have been extensively investigated, the mechanisms by which elevated hydrostatic pressure regulates endothelial junctional organisation remain sparsely investigated. Here, we employed a microfluidic platform to investigate the combined effects of low shear stress (1.4 dyne/cm2) and elevated hydrostatic pressure (~3972 Pa) on endothelial junctional dynamics. Elevated hydrostatic pressure induced marked remodelling of VE-cadherin junctions, characterised by formation of serrated, finger-like structures accompanied by increased YAP1 nuclear localisation and reduced YAP1-VE-cadherin cytoplasmic colocalisation compared to shear stress alone conditions. Further, elevated hydrostatic pressure also demonstrated an increase in cytoplasmic accumulation of EPS8, an actin adaptor protein, and increased cytoplasmic EPS8-VE-cadherin colocalisation. These observations were accompanied by functional changes marked by increased endothelial permeability, and enhanced THP-1 monocyte adhesion, thus suggesting activation of mechanosensitive pathways linked to dynamic junctional reorganisation. Inhibition of PI3K at elevated hydrostatic pressure exhibited a thin VE-cadherin patterning and increased cytoplasmic EPS8-VE-cadherin colocalisation, thus demonstrating a prominent role for PI3K signalling in regulating the junction organisation. Interestingly, Piezo-1 activation using Yoda1 produced context-dependent effects. Under shear stress alone, Yoda1 promoted YAP1 nuclear translocation, reduced YAP1-VE-cadherin colocalisation, increased endothelial permeability but strikingly did not impact THP-1 adhesion compared to shear stress alone conditions. In contrast, under elevated hydrostatic pressure conditions, Yoda1 significantly reduced both endothelial permeability and THP-1 adhesion while increasing YAP1-VE-cadherin colocalisation and decreasing YAP1 nuclear accumulation. Collectively, these findings identify a previously underappreciated elevated hydrostatic pressure-Piezo-1-PI3K signalling axis that regulates endothelial barrier integrity and pro-adhesive endothelial activation through coordinated regulation of VE-cadherin, YAP1, and EPS8. These results highlight elevated hydrostatic pressure as a unique mechanobiological stimulus, distinct from that of shear stress alone and provide novel insights into mechanisms underlying microvascular dysfunction.

Abstract Calcific deposits in the arterial media have been associated with a number of metabolic and genetic disorders including diabetes, chronic kidney disease and generalized arterial calcification of infancy. While medial calcification and physiologic hard tissue mineralization in the skeleton are both regulated by several common determinants, emerging data suggest that there might be fundamental differences in the mechanisms underlying these two processes. Objective: We previously demonstrated that elastin haploinsufficiency delays medial calcification in MGP-deficient mice. Here, using mice in which a human ELN transgene rescues mouse elastin deficiency, we investigated whether the origin and abundance of arterial elastin differentially affect the initiation and progression of medial calcification. Approach and Results: We pursued a transgenic approach to alter the arterial elastin scaffold in MGP-deficient mice. Our analyses of a humanized MGP-deficient model with 40% reduction of medial elastin content showed a complete absence of the early-stage vascular calcification. Additionally, we showed that mouse and human elastin orthologues affect vascular calcification in a comparable manner. Conclusion: Arterial elastin abundance, rather than orthologue origin, modulates the initiation and progression of medial calcification in MGP-deficient mice. A further reduction in arterial elastin beyond that achieved by elastin haploinsufficiency profoundly delays mineral deposition and maturation, whereas restoration of elastin abundance through transgenic human ELN expression restores arterial calcification.

Background Limited heart rate rise contributes to reduced exercise tolerance for people who have heart failure with reduced ejection fraction (HFrEF), yet rate-adaptive pacing does not improve functional capacity due to an attenuated force-frequency relationship (FFR). How the FFR relates to total peripheral resistance and sympathetic tone in HFrEF is unknown. Methods In a prospective, observational study, participants with HFrEF and controls underwent an incremental pacing protocol, during which heart rate was increased from 50 to 140 beats per minute. At each heart rate increment LV contractility was measured by echocardiography to determine the FFR, as well as continuous beat-to-beat measurement of systolic and diastolic blood pressures with a plethysmography device to determine cardiac output, total peripheral resistance and blood pressure variability (BPV). A microneurography study was then conducted to measure muscle sympathetic nerve activity (MSNA) during incremental pacing. Results A total of 157 participants with HFrEF and 55 controls (mean age 71.1{+/-}1.4 years, 172 (81.1%) male) underwent the pacing protocol. We observed single units in seven of 11 participants who participated in the microneurography study. In both groups, LV contractility and cardiac output increased until the peak of the FFR, after which these declined. We observed a reduction in total peripheral resistance, blood pressure variability, MSNA frequency and incidence coinciding with the peak of the FFR, beyond which these increased. Whilst these relationships were present in both groups, they were more evident in participants with HFrEF. Conclusions For people with HFrEF there is a bidirectional relationship between heart rate and sympathetic activation, with a nadir of sympathetic tone occurring at the peak of the FFR. Both excessively low and high heart rates are accompanied by greater sympathetic activation. Taken together, these data suggest that optimal heart rate targets for HFrEF are likely to be individual.

Background: Lumbar disc herniation, with or without concomitant disc degeneration, is a major cause of lumbar radiculopathy and low back pain, which also a key public musculoskeletal disorder without an exact pathophysiology. Studies have suggested that inflammatory cells and biochemical markers of inflammation also play an important role in lumbar radiculopathy in addition to nerve compression. The aim of the present study was to assess the association of selected circulatory inflammatory markers (CRP, hs-CRP and E-selectin) in patients with lumbar disc herniation without radiological degeneration (LDH) and lumbar disc herniation with radiological degeneration (LDHD). Materials & methods: This case-control study included 208 participants, comprising 104 patients with lumbar disc pathology and 104 controls. Patients were further stratified into LDH (n=67) and LDHD (n=37). Serum CRP, hs-CRP and E-selectin concentrations were measured. Results: Among the patients, 35.6 % presented with LDHD while 64.4 % had only LDH. Significantly increased median hs-CRP (p<0.001) and CRP (p<0.001) were observed in patients groups compared to controls, while CRP showing a consistent independent association across the combined disease (OR=1.68, 95% CI=1.33-2.14, p<0.001), LDHD (OR=1.62, 95% CI=1.16-2.20, p=0.005) and LDH (OR=1.69, 95% CI=1.30-2.20, p<0.001) multivariable models. No significant difference was observed in serum E-selectin between the study groups. Multivariable models incorporating inflammatory and clinical variables demonstrated substantially greater discriminatory performance than individual biomarkers alone. Conclusion: Elevated circulating CRP and hs-CRP concentrations were associated with lumbar disc pathology, with CRP showing a consistent independent association across the combined disease, LDH and LDHD multivariable models, whereas E-selectin showed no significant association. Multivariable models incorporating inflammatory and clinical variables demonstrated greater discriminatory performance than individual biomarkers. These findings support a potential systemic inflammatory component in lumbar disc pathology, although the cross-sectional nature of the measurements does not establish causality or a local inflammatory response within the disc.

Background: Acute phase response is an early immunometabolic response to brain injuries, primarily coordinated by the liver via the activation of acute phase proteins. These immune responses can be both beneficial, promoting tissue repair, and detrimental, exacerbating neurological deficits, if not properly controlled. Despite the central role of the liver in immunometabolism, how hepatic metabolism dynamically adapts to traumatic brain injury remains under explored, primarily due to limited liver-specific modalities that can assess metabolic pathways in vivo. 13C MRI utilizing hyperpolarized 13C-pyruvate can assess key regulatory enzyme activities in hepatic metabolism. Methods: Rats with controlled cortical impact were studied in vivo using hyperpolarized [1-13C]pyruvate and [2-13C]pyruvate under fed and fasted conditions 3-4 days after injury. Hyperpolarized 13C products, including [13C]bicarbonate from [1-13C]pyruvate and [5-13C]glutamate, [1-13C]acetyl-L-carnitine, and [2-13C]phosphoenolpyruvate from [2-13C]pyruvate, were evaluated to assess mitochondrial and gluconeogenic metabolism. In parallel, liver tissues were collected following [U-13C3]pyruvate injection for NMR isotopomer analysis of phosphoenolpyruvate, glucose, and glutamate. Results: While no metabolic differences were detected under fed condition, [13C]bicarbonate and [2-13C]phosphoenolpyruvate increased after brain injury under fasted condition, indicating an upregulation of the hepatic gluconeogenic pathway after injury. 13C NMR of liver tissue extracts from injured rats showed an elevated [2,3-13C2]glutamate-to-[4,5-13C2]glutamate ratio and increased 13C-labeling in phosphoenolpyruvate than controls, confirming enhanced hepatic gluconeogenic pathway. Conclusion: This study demonstrates that hepatic acute phase response to brain injuries can be monitored in vivo by hyperpolarized pyruvate, which may be further utilized for longitudinal immunometabolic evaluation of the liver during pathogenesis and therapeutic interventions.

Purpose: Otoacoustic emissions (OAEs) are used to assess outer hair cell (OHC) function. Clinical interpretation of OAE responses, however, is often limited to a present/absent binary since both physiological factors and measurement variability affect the measured OAE amplitude. Prior work showed elevated OAE responses in sedated compared to awake chinchillas, pointing to the potential influence of the medial olivocochlear (MOC) efferents on amplitudes, but this finding is inconsistent across species and OAE type. Here, we aimed to further investigate the effect of anesthesia on distortion- and reflection-type emissions in chinchillas using swept stimuli and more reliable calibration methods. Methods: Swept distortion-product (DP) and stimulus-frequency (SF) OAEs were measured in chinchillas with and without ketamine/xylazine sedation. Stimuli were presented using in-ear forward pressure level calibrations. DPOAE and SFOAE amplitudes and estimated Qerb from SFOAE group delays were compared across the two conditions. Results: We found that low-frequency DPOAE amplitudes were elevated when animals were sedated. The difference in SFOAE amplitudes was more variable across animals but appeared mildly reduced in sedated animals. Qerb estimates were slightly higher in sedated animals at some frequencies. The effect of sedation was not different across sexes. Conclusion: Taken together, these findings suggest that sedation impacts OAE measurements in chinchillas. MOC modulation could account for the present findings and differences across species. For diagnostic precision, OAE responses should be considered in the context of not only intrinsic OHC function but also extrinsic physiological processes that can modulate OHCs.

Coronary flow waveforms have a distinct diastolic-dominant shape with periods of low or retrograde flow during systole. While the general waveform shape has been attributed to complex interactions between cardiac and vascular mechanics, there is limited research into the variability in coronary flow waveforms and what this variability may reveal about cardiac function. This work presents a shape analysis of left anterior descending artery (LAD) flow waveforms using Fourier transforms and Singular Value Decomposition (SVD) performed on baseline data collected from 32 pigs. Pigs included in the study reflect two breeds (Ossabaw and Yorkshire) and three different experimental conditions (lean-control, lean-paced, and obese-paced). Fourier transforms were used to decompose the waveforms into 15 harmonics for each pig. An SVD analysis is then used to extract temporal patterns of the waveforms. Correlations between pig-specific coefficients for the SVD modes and clinical metrics were used to investigate physiological explanations of LAD waveform variability. Temporal LAD flow patterns of the second SVD mode are significantly correlated with heart rate. The third SVD mode significantly correlates with mean blood pressure and maximum hyperemic flow. Furthermore, the fourth SVD mode is weakly correlated with left-ventricular end diastolic pressure and endocardial-epicardial flow ratios. This work demonstrates that LAD flow waveforms can be broken down into temporal patterns that correlate with physiological features. Furthermore, this shape-analysis method allows for waveform reconstruction and simplifies visualization of the temporal patterns identified using SVD, an advantage over existing methods that focus on characterizing flow waveforms by points of interest.

Background. A primary constraint on the capacity of EMS programs to meet industry demand is psychomotor instruction and verification, requiring direct observation of each student by a qualified evaluator. Whether AI video analysis can relieve it is untested; none has been applied to EMS skill examination or compared with human examiners. Objective. To quantify human EMS evaluator inter-rater reliability and evaluate an AI video-analysis platform against it. Methods. In a prospective, fully crossed study, five certified EMS evaluators and an AI platform independently scored identical video-recorded EMT performances of cervical collar application (n=15), bag-valve-mask (BVM) ventilation (n=14), and medical assessment (n=15) on dichotomous checklists with critical-failure criteria. Agreement was assessed at item, score, and decision levels using Fleiss' kappa, Krippendorff's alpha, Gwet's AC1, and ICC(2,1)/ICC(2,k). Results. Human item agreement was moderate (kappa 0.409 to 0.467), as was single-rater reliability (ICC(2,1) 0.539 to 0.694), against good panel reliability (ICC(2,k) 0.854 to 0.919). Recorded pass/fail agreement was fair (kappa 0.297 to 0.388) and critical-failure agreement near zero for two skills (kappa 0.028, 0.119). AI alignment tracked rubric observability rather than task complexity: r = 0.857 (collar, exceeding every human), -0.173 (BVM), 0.664 (medical), and it was most lenient on two skills. Conclusions. Human evaluators are an imperfect standard, especially on critical failures. The AI was a legitimate additional rater where checklist items were discrete and visually verifiable, but not where credit required judging continuous quantities such as ventilation rate, volume, or suction duration. Defensible uses are formative and archival, not summative. These results reflect an early, non-specialist configuration: a baseline, not a limit.

Background: HFpEF accounts for roughly half of heart failure admissions and lacks disease-modifying therapy. Autotaxin (ENPP2) generates lysophosphatidic acid (LPA), a profibrotic and pro-inflammatory bioactive lipid. Whether circulating lysophospholipid metabolism is altered in HFpEF, and whether autotaxin inhibition modifies an established experimental HFpEF phenotype, is untested. Methods: Plasma from patients with HFpEF (n=210) and non-heart-failure comparators (n=27) underwent untargeted and LPA-targeted mass spectrometry and a nine-analyte multiplex immunoassay. Male C57BL/6J mice received a high-fat diet plus L-NAME (0.85 g/L) or chow for 5 weeks; after phenotype confirmation, they received oral PF-8380 (30 mg/kg/day) or vehicle for 10 weeks. Endpoints were echocardiography, functional assessment, gravimetric studies, tail-cuff pressure, trichrome fibrosis, and flow cytometry of heart and spleen. Results: All nine analytes, including the autotaxin protein ENPP2, were higher in HFpEF than comparators. HFpEF plasma showed higher LPE O16:1, LPE O18:2, PS 38:4 and PC 36:4;O, and lower SM 39:2; O3 and PS 36:0. LPA 20:0 was 3.5-fold higher in both sexes, whereas LPA 18:2 was lower in women. Diet plus LNAME raised blood pressure, LV mass, and isovolumic relaxation time with preserved ejection fraction. PF-8380 reduced echocardiographic indices of diastolic dysfunction, fibrosis area, cardiomyocyte area, and cardiac CD11b+, CD64+, CD86+, and Ly6G+ frequencies, without altering fat or lean mass. Conclusion: In male mice with established two-hit HFpEF, autotaxin inhibition improved diastolic indices and reduced fibrosis, hypertrophy, and cardiac myeloid accumulation. Human data show altered lysophospholipid composition. Collectively, these findings nominate the autotaxin/LPA axis as a tractable therapeutic target and support further evaluation of autotaxin inhibition as a candidate disease-modifying strategy for HFpEF management.

Background: Pressure ulcers often develop complex three-dimensional morphologies that extend beyond the visible wound surface. Subsurface extensions such as tunneling and undermining create hidden cavities that complicate clinical assessment and wound management. Despite their clinical relevance, the prevalence and spatial characteristics of these subsurface wound morphologies have not been well characterized at scale. Methods: We performed a registry-based analysis using data from the LIFT-OFF Pressure Ulcer Registry, which captures longitudinal clinical documentation of pressure ulcers treated in routine care. The registry included approximately 18,000 patients with 32,000 documented pressure ulcers. Spatial characteristics of tunneling and undermining were analyzed using measurements recorded during routine wound assessments, including tract length, direction, and circumferential extent. Directional and circumferential distributions of subsurface defects were examined to characterize wound geometry. Results: Tunneling was present in 764 of 14,700 full-thickness pressure ulcers (5.2%), whereas undermining occurred in 2,293 wounds (15.6%). Tunneling tracts were typically short and exhibited directional clustering relative to the wound bed. In contrast, undermining demonstrated broader circumferential distributions and frequently involved larger subsurface separations beneath the wound margin. Both morphologies demonstrated distinct spatial patterns across anatomical locations and wound stages. Conclusion: Tunneling and undermining are common subsurface features of pressure ulcers and exhibit distinct spatial geometries. Whereas tunneling manifests as directional tract-like extensions, undermining more frequently produces circumferential tissue separation beneath wound margins. Improved characterization of subsurface wound architecture may enhance assessment of wound complexity and provide information not captured by surface measurements alone. Future studies should evaluate whether these features contribute to wound severity assessment, prognosis, and risk stratification.

Objective: The Brief-cope questionnaire explore coping behavior. However, the underlying factor structure remains a subject of ongoing debate. Exploratory factor analyses (EFA) conducted across different populations have identified factor solutions ranging from two to fourteen factors. As of yet, the underlying factor structure of the Brief-cope has not been investigated in patients with seropositive rheumatoid arthritis (RA). Therefore, the aim of this study was to explore the underlying factor structure of the Brief-cope in a German population of seropositive RA. Methods: 216 outpatients with seropositive RA completed the Brief-cope. An EFA with principal axis factoring and Promax rotation was conducted. Results: EFA indicated a five-factor solution. The five-factor solution explained 51.95% of variance. The identified factors were: (1) problem-focused coping (Cronbach's = .851), (2) emotion-focused coping ( = .754), (3) maladaptive coping ( = .747), (4) religious coping ( = .851), and (5) substance-use coping ( = .869). Conclusion: A five-factor solution provided the most appropriate representation of the underlying factor structure of the Brief-cope in patients with seropositive RA. This factor structure may serve as a suitable basis for future analyses of Brief-cope data in comparable RA populations.

Importance: Evidence on GLP-1/GIP therapies is largely derived from trials enrolling selected populations or medical records that miss utilization outside healthcare channels. No nationally representative cohort has characterized real-world uptake, indications, and access. Objective: To characterize GLP-1/GIP prevalence, indication, clinical profile, and access. Design: Prospective cohort study with three GLP-1/GIP surveillance waves (March 2024, December 2024, October 2025). Setting: The Understanding America Study, an address-based, nationally representative panel of approximately 15,000 US adults aged 18+ years initiated in 2014. Participants: UAS participants responding to at least one surveillance wave (n=9150). Exposures: GLP-1/GIP use status (never vs any use, comprising current and former use), self-reported primary indication (diabetes, weight loss, or other), and access pathway (traditional vs non-traditional). Main Outcomes and Measures: Survey-weighted prevalence of GLP-1/GIP use, overall and by indication and access pathway; sociodemographic, cardiometabolic, treatment, and access characteristics; and smartwatch-derived resting heart rate, heart rate variability, maximum activity heart rate, step count, and sleep duration and variability. Results: Among n=9150 adults (1274 with any use; 60.9% female; median age 53 years), weighted prevalence increased 46%, from 8.2% (March 2024) to 12.0% (October 2025) representing 32 million. Weight-loss indications grew, reaching nearly half of use (4.1% to 5.6%); diabetes-indicated use was stable (5.3% to 5.4%). Users carried high cardiometabolic burden (obesity, 68.2%; diabetes, 53.6%) but diverged by indication: diabetes-indicated users were older (median, 59 vs 49 years), whereas weight-loss-indicated users were more often female (69.9% vs 51.3%) and healthier. One in three users (~9 million) had non-traditional access, especially in weight-loss-indicated users, of whom 33% had no conventional prescription; 41% used compounding, online, or foreign pharmacies; and, 43% lacked coverage. Non-traditional users were five times as likely to report an unlisted, likely compounded formulation (19.8% vs 4.1%). All p<0.05. Conclusions and Relevance: Real-world GLP-1/GIP use has grown rapidly and diversified substantially in indication, access, and population profile. One in 3 users obtained treatment through nontraditional channels largely invisible to claims data, raising long-term safety, efficacy, and coverage questions. GLIMMER provides a public, nationally representative longitudinal evidence base for future payer and provider decisions.

Objectives To evaluate whether access to a certified large language model (LLM)-based clinical decision support system improves physician diagnostic performance in rheumatology compared with conventional diagnostic resources alone. Methods In this multicentre, open-label, randomised controlled trial, 82 physicians from seven hospitals in two countries were randomised 1:1 to conventional diagnostic resources plus Prof. Valmed or conventional resources alone. Participants assessed three rheumatology vignettes before and after assistance. The primary outcome was top-1 diagnostic accuracy. Secondary outcomes included top-3 accuracy, diagnostic reasoning, confidence, case-processing time and perceived support quality. Results Top-1 accuracy increased from 22.2% to 33.3% in the intervention group and from 23.3% to 35.0% in the control group, with no between-group difference in improvement (adjusted OR 0.99, 95% CI 0.45 to 2.19; p=0.979). Differences in top-3 accuracy, diagnostic reasoning and confidence were also not significant. Assisted case-processing time was substantially shorter with LLM support (94 vs 206 s; adjusted mean difference -112 s, 95% CI -141 to -83; p<0.001). Information timeliness and perceived diagnostic support quality were rated significantly higher in the intervention group. Exploratory analyses showed persistent overconfidence and substantial AI over-reliance. Conclusions Certified LLM-based diagnostic support did not improve diagnostic accuracy compared with conventional resources, but substantially reduced case-processing time and improved perceived support quality. These findings suggest potential workflow benefits while highlighting overconfidence and over-reliance as important safety considerations.

Purpose: To evaluate the safety, procedural performance, sample recovery, and surgeon preference of an ophthalmic needle designed specifically for anterior chamber (AC) paracentesis. Methods: In this multicenter study, AC paracentesis was performed in clinic and operating-room settings using a 32-gauge x 4-mm needle with low dead space. The procedure was evaluated using a standardized physician survey. Prespecified outcomes included procedure-related adverse events (primary outcome), needle entry and handling, aspiration and sample recovery, comparative performance versus a 30-gauge needle, and physician preference for future use. Results: A total of 110 needle uses by eight surgeons were included. No ocular complications occurred, including lens or iris injury, hyphema, AC collapse, wound leak, hypotony, infection, or retinal complication, and no procedure required needle exchange or conversion to another device. Two technical events without ocular sequelae were noted, in which needle entry was partial thickness and did not reach the AC (1.8%; exact 95% CI, 0.2%-6.4%). Physicians rated needle entry, handling and sample recovery as good or excellent. Compared with a 30-gauge needle, the study needle was rated as at least comparable across all assessed domains. All surgeons rated it better or much better for intra-procedural safety and preferred it for future AC taps. Conclusions and Relevance: This short, 32-gauge low-dead-space ophthalmic needle demonstrated a favorable safety profile and was preferred over a 30-gauge needle by all surgeons. As aqueous humor liquid biopsy expands in clinical diagnostics and trials, an ophthalmic-specific needle design may help improve the consistency and safety of aqueous humor collection for molecular analysis and broader clinical use. Keywords: Anterior chamber paracentesis; Aqueous humor; Liquid biopsy; Low dead space; Ophthalmic needle