Citations

Objectives/Goals: Longitudinal studies capture dynamic host–environment interactions crucial to microbiome research. Commonly used mixed-effects models can struggle with small clinical samples, like many endometrial cancer studies. We will compare them to simpler fixed-effects models, aiming to develop a new fixed-effects differential abundance alternative. Methods/Study Population: Starting with simulated data for linear models with a single treatment effect, we will incrementally increase complexity to reflect real-world microbiome data. To observe conditions of misspecification, simulated data of repeated measures will be generated using different distributions, while varying parameters and inter-class correlation. In each condition, linear fixed- and mixed-effects models will be fitted 1000 times to empirically determine p-value, type 1 error rate, and power. We will increase the verisimilitude of our approach by using endometrial cancer data from our lab as a real background, while adding simulated signals. This data will be used to assess extant differential abundance models against our novel fixed-effects model. Results/Anticipated Results: Our initial findings indicate that fixed-effects models maintain control over type 1 error rates in small samples, while mixed-effects models do not perform as reliably. We are now exploring the effects of confounders on type 1 error rates and power in linear models, while our next step will evaluate generalized linear models in a differential abundance context. We expect that the fixed-effects models will continue to be as reliable as mixed-effects models, while being less computationally complex. After establishing our theoretical basis, our novel model should perform comparably to mixed-effects models on pseudo-simulated endometrial cancer data and better at small sample sizes. We will finally apply our model to real endometrial cancer data to identify microbial markers of disease predisposition. Discussion/Significance of Impact: By characterizing and improving these statistical tools, we seek to increase the robustness and power of microbiome study results (especially at small sample sizes), ultimately supporting better-informed translational research decisions. This work underscores the importance of statistical methods in advancing microbiome research.

Abstract Pancreatic neuroendocrine tumors (PanNETs) have an age-adjusted incidence of 1.5 per 100,000 people, with a notable rise in the incidence of small (≤2 cm) non-functional PanNETs (NF-PanNETs) in recent decades. While surgery is traditionally the preferred treatment for localized NF-PanNETs, active surveillance is now an accepted management strategy for tumors smaller than 2 cm due to their relatively benign behavior. However, this approach has not yet been fully integrated into routine clinical practice. There is considerable histopathological heterogeneity observed in NF-PanNETs, which results in significant variability in clinical presentation, behavior and treatment outcomes. Hence, tumor size alone does not provide sufficient certainty regarding a benign clinical course for decision-making. Although studies advocate for incorporating WHO grade into clinical prognostic assessments, this marker also has limitations. Several established tissue-based markers, such as ATRX and DAXX alterations, alternative lengthening of telomeres, and copy number variations, can be used for PanNET subtyping and correlate with metastatic risk. Combining these markers with traditional histopathological parameters may yield a more comprehensive and accurate prognostic assessment. This review discusses the advantages and limitations of current prognostication methods for small NF-PanNETs and highlights recently established prognostic markers, along with the requirements for their implementation into routine clinical practice. It also proposes practical solutions to address the challenges associated with the immediate integration of these biomarkers into routine care.

Background Spinal subdural empyema rarely involves the spinal cord and may result in devastating neurological deficits. These lesions typically require prompt diagnosis, surgical evacuation, and antibiotic therapy. Here, we present the clinical course, imaging, and narrated operative video of a thoracic spinal subdural empyema initially diagnosed as an intramedullary neoplasm. Case Description A 73-year-old female presented with a 6-month history of worsening thoracic myelopathy; over the last few weeks, she rapidly developed paraplegia. She was initially diagnosed with an enlarging thoracic intramedullary mass. A spinal biopsy was performed for the presumptive diagnosis of primary intramedullary central nervous system lymphoma. However, at surgery, the thoracic lesion proved to be a chronic subdural empyema (i.e., surrounded by arachnoid granulations and soft-purulent tissue). Interestingly, the operative specimen failed to grow any specific organism. Conclusion Spinal subdural empyema should be one of the differential diagnoses considered for patients presenting with intradural spinal cord lesions.

Background: Many surgeons recommend weight loss for patients with obesity before total joint arthroplasty (TJA), but few studies have evaluated weight loss interventions. This study compared weight loss using a remote dietitian and a mobile application (app) with weight loss using standard care for patients with severe obesity before TJA. Methods: This multicenter randomized controlled trial included 60 subjects with a body mass index (BMI) of 40 to 47 kg/m 2 who had been scheduled for primary total hip or knee arthroplasty from September 2019 to January 2023. The mean age was 61 years, 67% were women, and the mean BMI was 44 kg/m 2 . The control subjects (n = 29) received standard care; the intervention subjects (n = 31) completed video calls with dietitians and used a mobile app for 12 weeks preoperatively. Weights and surveys were collected at baseline and 12 weeks, with 87% follow-up. Weight loss, patient-reported outcomes, complications, revisions, and reoperations were compared. The mean follow-up was 1.8 years. Results: The intervention subjects lost more weight (−4.1 versus −2.1 kg, p = 0.22) and had larger decreases in BMI (−1.4 versus −0.9 kg/m 2 , p = 0.36 than the controls, but not significantly so. The intervention subjects had higher odds of achieving a BMI of <40 kg/m 2 (odds ratio = 1.9, p = 0.44), but not significantly so. There were no significant differences in the mean change in the Hip disability and Osteoarthritis Outcome Score, the Knee injury and Osteoarthritis Outcome Score, or the Lower Extremity Activity Scale score. At baseline, only 11% had seen a dietitian in the last 3 months. Most subjects (83%) felt that video calls were helpful. There were no differences in complications between the groups; there was a patellar fracture in the control group and a deep venous thromboembolism in the intervention group. Conclusions: A preoperative weight loss intervention using a dietitian and a mobile app was feasible and viewed favorably among patients. Remote dietitians and mobile apps may address gaps in access to obesity treatment before TJA. While the intervention subjects lost more weight and were more likely to achieve a BMI of <40 kg/m 2 , the differences were not significant. More intensive interventions may be needed to achieve enough weight loss for clinically important improvements in TJA. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Précis: 240-degree and 360-degree goniotomy (GT) demonstrated similar efficacy in intraocular pressure (IOP) reduction, both outperforming 120-degree GT in patients with juvenile open angle glaucoma (JOAG) at postoperative 6-month follow-up. Objective: To compare the surgical efficacy and safety of 120-degree, 240-degree, and 360-degree GT for patients with JOAG. Patients and Methods: This multicenter retrospective study included 102 eyes of 102 patients with JOAG, who underwent GT with a follow-up of at least 6 months. Patients were categorized into 3 groups: (1) 120-degree GT, (2) 240-degree GT, and (3) 360-degree GT. IOP, glaucoma medications, and complications were recorded at baseline and the final visit. Complete success and qualified success were defined as a postoperative IOP ≤21 mm Hg without and with medications, respectively. Results: Mean age of the participants was 24.4 ± 7.9 years. After a mean follow-up of 8.1 ± 2.7 months, complete success rates were similar between the 240-degree GT (45.2%) and the 360-degree GT (63.2%; P = 0.135), and both were superior to 120-degree GT (18.2%; P < 0.05). Qualified success rates among patients in the 120-degree, 240-degree, and 360-degree GT groups were 93.9%, 96.8%, and 100%, respectively, and showed no statistically significant difference (P = 0.292). 360-degree GT required fewer medications than 240-degree GT and 120-degree GT (P < 0.05), with no significant difference in medications between 120-degree GT and 240-degree GT (P > 0.05). Hyphema was the most common postoperative complication, with a significantly higher incidence in the 360-degree GT (68.4%) compared with the 240-degree GT (41.9%) and 120-degree GT (33.3%; P < 0.05). Conclusions: 240-degree and 360-degree GT showed similar efficacy in IOP reduction and were superior to 120-degree GT. More extensive GT may provide better outcomes in JOAG.

The interplay between intracellular and intravascular lipolysis is crucial for maintaining circulating lipid levels and systemic energy homeostasis. Adipose triglyceride lipase (ATGL) and lipoprotein lipase (LPL), the primary triglyceride (TG) lipases responsible for these two spatially separate processes, are highly expressed in adipose tissue. Yet the mechanisms underlying their coordinated regulation remain undetermined. Here, we demonstrate that genetic ablation of G0S2, a specific inhibitory protein of ATGL, completely abolished diet-induced hypertriglyceridemia and significantly attenuated atherogenesis in mice. These effects were attributable to enhanced whole-body TG clearance, not altered hepatic TG secretion. Specifically, G0S2 deletion increased circulating LPL concentration and activity, predominantly through LPL production from white adipose tissue (WAT). Strikingly, transplantation of G0S2-deficient WAT normalized plasma TG levels in mice with hypertriglyceridemia. In conjunction with improved insulin sensitivity and decreased ANGPTL4 expression, the absence of G0S2 enhanced the stability of LPL protein in adipocytes, a phenomenon that could be reversed upon ATGL inhibition. Collectively, these findings highlight the pivotal role of adipocyte G0S2 in regulating both intracellular and intravascular lipolysis, and the possibility of targeting G0S2 as a viable pharmacological approach to reducing levels of circulating TGs.

ABSTRACT Understanding lung cancer evolution can identify tools for intercepting its growth. In a landscape analysis of 1024 lung adenocarcinomas (LUAD) with deep whole-genome sequencing integrated with multiomic data, we identified 542 LUAD that displayed diverse clonal architecture. In this group, we observed an interplay between mobile elements, endogenous and exogenous mutational processes, distinct driver genes, and epidemiological features. Our results revealed divergent evolutionary trajectories based on tobacco smoking exposure, ancestry, and sex. LUAD from smokers showed an abundance of tobacco-related C:G>A:T driver mutations in KRAS plus short subclonal diversification. LUAD in never smokers showed early occurrence of copy number alterations and EGFR mutations associated with SBS5 and SBS40a mutational signatures. Tumors harboring EGFR mutations exhibited long latency, particularly in females of European-ancestry (EU_N). In EU_N, EGFR mutations preceded the occurrence of other driver genes, including TP53 and RBM10. Tumors from Asian never smokers showed a short clonal evolution and presented with heterogeneous repetitive patterns for the inferred mutational order. Importantly, we found that the mutational signature ID2 is a marker of a previously unrecognized mechanism for LUAD evolution. Tumors with ID2 showed short latency and high L1 retrotransposon activity linked to L1 promoter demethylation. These tumors exhibited an aggressive phenotype, characterized by increased genomic instability, elevated hypoxia scores, low burden of neoantigens, propensity to develop metastasis, and poor overall survival. Re-activated L1 retrotransposition-induced mutagenesis can contribute to the origin of the mutational signature ID2, including through the regulation of the transcriptional factor ZNF695 , a member of the KZFP family. The complex nature of LUAD evolution creates both challenges and opportunities for screening and treatment plans.

Abstract This retrospective analysis aimed to provide evidence-based risk stratification of TP53-mutated (TP53mut) myeloid neoplasms (MNs). Of 580 MNs harboring TP53mut with variant allele frequency (VAF) ≥2%, 219 (37.8%), 194 (33.4%), 92 (15.9%), and 75 (12.9%) were classified as acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) with low blasts (MDS-LB), MDS with excess blasts (MDS-EB)-2, and -EB1 according to the revised fourth edition of the World Health Organization (WHO) classification, respectively. Hierarchical analysis identified the following 4 risk groups with distinct survival: (1) MDS-LB, (2) MDS-EB1/EB2/AML VAF &lt;10%, (3) MDS-EB1/EB2 VAF ≥10%, and (4) AML VAF ≥10%. We next evaluated the impact of allelic status, VAF, and complex karyotype (CK). In our cohort, the significance of biallelic status was limited to MDS with &lt;5% blasts and not for blasts 5% to 9%, as proposed by the International Consensus Classification (ICC), or 5% to 19%, as proposed by the fifth edition of the WHO (WHO-5). MDS-EB1 and -EB2 with VAF ≥10% had comparable survival (9.6 vs 7.2 months; P = .12), regardless of allelic status. Contrary to the ICC proposal, MDS-EB1/EB2 with VAF &lt;10% and CK had poor survival compared with those without CK, comparable to MDS-EB1/EB2 with VAF ≥10% (5.6 vs 26.2 vs 6.3 months; P = .003). Survival of TP53mut AML was poor (median 3.9 months) regardless of allelic/CK status. Thus, using ICC or WHO-5 may underestimate prognosis of MDS with blasts 5% to 19% and 5% to 9%, respectively. Collectively, the hierarchical model acknowledges poor survival of 91.9% TP53mut MDS and AML compared with 36.5% and 80.7% by WHO-5 and ICC, respectively.