Elevated Burden Research Articles

GPRASP protein deficiency triggers lymphoproliferative disease by affecting B-cell differentiation.

Gprasp1 and Gprasp2 encode proteins that control the stability and cellular trafficking of CXCR4, a master regulator of hematopoiesis whose dynamic regulation is required for appropriate trafficking of B-cells in the germinal center (GC). Here, we report that Gprasp1 and Gprasp2-deficient B-cells accumulate in the GC and show transcriptional abnormalities, affecting the mechanisms controlling Aicda expression and exposing them to excessive somatic hypermutation. Consequently, about 30% of mice transplanted with Gprasp-deficient hematopoietic stem and progenitor cells developed a biologically aggressive and fatal B-cell hyperproliferative disease by 20-50 weeks posttransplant. Histological and molecular profiling reveal that Gprasp1- and Gprasp2-deficient neoplasms morphologically resemble human high-grade B-cell lymphomas of germinal center origin with shared morphologic features of both Burkitt Lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL), and molecular features consistent with DLBCL, as well as elevated mutational burden and heterogenous transcriptional and mutational signature. Thus, reduced Gprasp1 and Gprasp2 gene expression perturbs B-cell maturation and increases the risk of B-cell neoplasms of germinal center origin. As this model recapitulates the essential features of the heterogenous group of human hematopoietic malignancies, it could be a powerful tool to interrogate the mechanisms of lymphomagenesis for these cancers.

Association of Neutrophil extracellular traps burden with clinical and angiographic characteristics in patients with ST-elevation myocardial infarction

Abstract Background The precise triggers for arterial plaque rupture and the underlying pathophysiology of thrombogenesis remain elusive. Polymorphonuclear neutrophils (PMN), particularly their formation of Neutrophil Extracellular Traps (NETs), have garnered attention in the context of coronary atherothrombosis. This study sought to explore the association of NETs burden with clinical and angiographic characteristics in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) and thrombus aspiration (TA). Methods This study included 336 consecutive STEMI patients undergoing pPCI and TA. Aspirated thrombi underwent histological analysis and NETs quantification via immunohistochemistry. Potential associations of clinical variables and angiographic outcomes with NETs burden were assessed. Results Manual TA was selectively performed in 72 cases with increased thrombotic burden and 60 thrombi were suitable for analysis. Most thrombi specimens displayed lytic features (63%) and almost three out of four specimens were identified as white thrombi. Increased NETs burden was significantly associated with prolonged pain-to-balloon time (>300 minutes) OR=10.29 (95% CI 2.11-42.22, p=0.001) and stress-induced hyperglycemia (SIH) OR=6.58 (95% CI 1.23-52.63, p=0.04) after multivariate regression analysis. Additionally, distal embolization (DE), a predictor of adverse outcomes, was more frequent among patients with an elevated NETs burden OR=16.9 (95% CI 4.23-44.52, p<0.001). Conversely, no significant association between NETs burden and final TIMI flow=3 was observed. Conclusion Elevated NETs burden in STEMI thrombi is linked to delayed reperfusion, SIH and increased risk of DE. Further research is needed to elucidate the role of NETs as a potential therapeutic target in acute atherothrombosis.

Intraplaque hemorrhage in carotid atherosclerotic plaques is associated with a local increase in inflammatory cytokines

Abstract Background One of the main features of vulnerability in atherosclerotic carotid plaques is intraplaque hemorrhage (IPH), which is related to a higher incidence of cerebrovascular events in patients with carotid artery disease. Additionally, inflammation plays a pivotal role in the progression of atherosclerotic disease. Purpose We aimed to determine plasma and tissue levels of inflammatory cytokines in patients with carotid artery disease hypothesizing that plaques with IPH are characterized by the presence of a more inflamed environment. Methods We retrospectively enrolled 104 consecutive patients undergoing carotid endarterectomy (CEA) with symptomatic (ischemic stroke, TIA, amaurosis fugax) or asymptomatic ipsilateral carotid artery disease. Plasma and carotid plaque specimens were collected at CEA. The tissue samples were stained with H&E to identify IPH and classified as specimens with and without IPH. Frozen homogenates of both plasma and tissue were analyzed using a customized 10-plex Luminex assay to determine the levels of inflammatory cytokines such as MCP-1/CCL2, IL-8/CXCL8, IFN-gamma, IL-10, IL-1beta/IL-1F2, IL-6, PDGF-AA, PDGF-AB/BB, TNF-alpha, and VEGF. Results IPH was identified in 53 patients (51.0 %). Cytokine levels in plasma and tissue from patients with and without IPH are reported in Table 1. In the univariate logistic regression MCP-1/CCL2, IL-8/CXCL8, IFN-gamma, IL-10, IL6, PDGF-AA, and PDGF-AB/BB were associated with IPH (Table 2). In the multivariate logistic regression, IL-6 was an independent predictor of IPH (HR 1.026 [95% CI 1.005-1.047]; p=0.014) after adjusting for cardiovascular risk factors such as age, BMI, sex, hypertension, diabetes mellitus, hyperlipidemia, ipsilateral carotid stenosis %. Conclusions Carotid plaques with IPH have an elevated inflammatory burden, potentially impacting adverse outcomes in this patient cohort. The local inflammatory cytokines in carotid plaques with IPH might serve as biomarkers and therapeutic targets in patients with carotid artery disease.

Conduction system versus right ventricular pacing for atrioventricular block: a reconstructed individual participant data meta-analysis

Abstract Background Right ventricular pacing (RVP) is typically offered to patients with established or impending atrioventricular block (AVB) in the absence of left ventricular systolic dysfunction. Direct stimulation of His-Purkinje fibres via conduction system pacing (CSP) is an emerging alternative to RVP to prevent pacing-induced cardiomyopathy. Purpose To perform a systematic review and meta-analysis testing CSP versus RVP in patients with AVB and a left ventricular ejection fraction ≥35%. Methods Observational studies comparing CSP with RVP that reported clinical outcomes were systematically identified. The primary outcome was time-to-first all-cause mortality, heart failure hospitalisation (HFH) or upgrade to biventricular pacing. Secondary endpoints included the individual components of the primary endpoint. Individual participant time-to-event data (IPD) was obtained through data-sharing agreements or reconstructed from digitisation of Kaplan-Meier curves where available. Mixed-effects Cox proportional hazards regression that modelled between-study heterogeneity as a random intercept to account for differing baseline hazards between distinct study populations was performed on these data. Conventional pairwise random effects meta-analyses were also performed. This analysis was prospectively registered. Results 12 eligible studies enrolling 4627 patients were included. In reconstructed IPD pooled survival analyses, CSP associated with a 38% reduced hazard of the primary endpoint compared with RVP [hazard ratio 0.62, 95% CI 0.51 to 0.76, p<0.001] (Figure 1). In pairwise meta-analyses, CSP associated with a 46% risk reduction in the primary endpoint [relative risk (RR) 0.54, 95% CI 0.41 to 0.71, p<0.001] (Figure 2A). CSP also associated with reductions in risk of all-cause mortality [RR 0.60, 95% CI 0.45 to 0.80, p<0.001], HFH [RR 0.39, 95% CI 0.28 to 0.55, p<0.001] and upgrade to biventricular pacing [RR 0.19, 95% CI 0.07 to 0.52, p=0.001] compared with RVP (Figure 2B-D). Conclusions In reconstructed IPD pooled survival analyses, CSP associated with reductions in the primary composite endpoint of all-cause mortality, heart failure hospitalisation or upgrade to biventricular pacing compared with RVP, independent of ventricular pacing burden. This was mirrored in conventional meta-analyses of the primary composite endpoint, and when individual components of the composite were analysed. It may not be necessary to predict which patients will have an elevated pacing burden when applying this therapy. Until randomised data from the PROTECT-HF trial becomes available, this analysis offers the most precise summary estimate of the comparative effects of CSP versus RVP in patients with an AVB indication for pacing, but no evidence of heart failure.Kaplan-Meier plot comparing CSP vs RVPForest plots for major endpoints

A burden of rare copy number variants in obsessive-compulsive disorder.

Current genetic research on obsessive-compulsive disorder (OCD) supports contributions to risk specifically from common single nucleotide variants (SNVs), along with rare coding SNVs and small insertion-deletions (indels). The contribution to OCD risk from rare copy number variants (CNVs), however, has not been formally assessed at a similar scale. Here we describe an analysis of rare CNVs called from genotype array data in 2248 deeply phenotyped OCD cases and 3608 unaffected controls from Sweden and Norway. Cases carry an elevated burden of CNVs ≥30 kb in size (OR = 1.12, P = 1.77 × 10-3). The excess rate of these CNVs in cases versus controls was around 0.07 (95% CI 0.02-0.11, P = 2.58 × 10-3). This signal was largely driven by CNVs overlapping protein-coding regions (OR = 1.19, P = 3.08 × 10-4), particularly deletions impacting loss-of-function intolerant genes (pLI >0.995, OR = 4.12, P = 2.54 × 10-5). We did not identify any specific locus where CNV burden was associated with OCD case status at genome-wide significance, but we noted non-random recurrence of CNV deletions in cases (permutation P = 2.60 × 10-3). In cases where sufficient clinical data were available (n = 1612) we found that carriers of neurodevelopmental duplications were more likely to have comorbid autism (P < 0.001), and that carriers of deletions overlapping neurodevelopmental genes had lower treatment response (P = 0.02). The results demonstrate a contribution of rare CNVs to OCD risk, and suggest that studies of rare coding variation in OCD would have increased power to identify risk genes if this class of variation were incorporated into formal tests.

Pan-cancer analysis of Sp1 with a focus on immunomodulatory roles in gastric cancer

BackgroundSp1, a transcription factor, regulates essential cellular processes and plays important tumorigenic roles across diverse cancers. However, comprehensive pan-cancer analyses of its expression and potential immunomodulatory roles remain unexplored.MethodsUtilizing bioinformatics tools and public datasets, we examined the expression of Sp1 across normal tissues, tumors, and immune cells, and screened for pre- and post-transcriptional modifications, including genetic alterations, DNA methylation, and protein phosphorylation, affecting its expression or function. The association of Sp1 expression with immune cell infiltration, tumor mutational burden, and immune checkpoint signaling was also investigated. Single-cell transcriptome data was used to assess Sp1 expression in immune cells in gastric cancer (GC), and findings were corroborated using immunohistochemistry and multiplex immunofluorescence in an immunotherapy-treated patient cohort. The prognostic value of Sp1 in GC patients receiving immunotherapy was evaluated with Cox regression models.ResultsElevated Sp1 levels were observed in various cancers compared to normal tissues, with notable prominence in GC. High Sp1 expression correlated with advanced stage, poor prognosis, elevated tumor mutational burden (TMB), and microsatellite instability (MSI) status, particularly in GC. Significant correlations between Sp1 levels and CD8+ T cell and the M1 phenotype of tumor-associated macrophages were further detected upon multiplex immunofluorescence in GC samples. Interestingly, we verified that GC patients with higher Sp1 levels exhibited improved response to immunotherapy. Moreover, Sp1 emerged as a prognostic and predictive biomarker for GC patients undergoing immunotherapy.ConclusionsOur pan-cancer analysis sheds light on the multifaceted role of Sp1 in tumorigenesis and underscores its potential as a prognostic and predictive biomarker for patients with GC undergoing immunotherapy.

Molecular Testing in Gliomas: What is Necessary in Routine Clinical Practice?

A number of molecular characteristics are essential for accurate diagnosis and prognostication in glioma. The 2021 WHO classification of brain tumors and recent Food and Drug Administration (FDA) pathology agnostic drug approvals highlight the importance of molecular testing in the management of glioma. For diffuse gliomas, it is important to identify IDH mutations, given the favorable clinical behavior and potential for using FDA approved IDH inhibitors in the near future. MGMT promoter methylation testing is the most established molecular marker for response to temozolomide in IDH wild-type glioblastoma and in turn impacts overall survival. Moreover, identification of certain mutations and molecular markers, such as BRAF V600E, hypermutation or elevated tumor-mutational burden and NTRK fusions allow for the use of FDA approved agents that are tumor-agnostic. Finally, molecular testing opens options for clinical trials that are essential for diseases with limited treatment options like gliomas.

Cryo-EM structure of Alzheimer’s disease tau filaments with PET ligand MK-6240

Positron Emission Tomography (PET) ligands have advanced Alzheimer’s disease (AD) diagnosis and treatment. Using autoradiography and cryo-EM, we identify AD brain tissue with elevated tau burden, purify filaments, and determine the structure of second-generation high avidity PET ligand MK-6240 at 2.31 Å resolution, which bound at a 1:1 ratio within the cleft of tau paired-helical filament (PHF), engaging with glutamine 351, lysine 353, and isoleucine 360. This information elucidates the basis of MK-6240 PET in quantifying PHF deposits in AD and may facilitate the structure-based design of superior ligands against tau amyloids.

In-situ induced formation of Fe-OM association in soil: Theory and practice of remediation of cadmium contaminated paddy fields in high cadmium geological background areas

Cadmium (Cd) pollution in rice paddies, attributable to high geological Cd backgrounds, has emerged as a global concern. This study leverages the passivation mechanism of bioavailable Cd by iron-organic matter associations (Fe-OM) to explore a novel strategy for Cd immobilization. We examined the adsorptive capacity and removal efficiency of Cd by laccase-mediated Fe-OM association and assessed their natural stability using 57Fe isotopic tracing. Additionally, we conducted in-situ remediation trials in a Cd-enriched paddy soil. Our results indicate that the theoretical maximum adsorption capacity for Cd by the laccase-mediated Fe-OM is 100.0 mg/g, which is a 15% improvement over the common Fe-OM and a 150% enhancement over inorganic iron oxides (ferrihydrite). The 57Fe isotope tracing test showed that the affinity of laccase-modified organic matter for iron increased by 55.6%, and it exhibited better stability than common Fe-OM under anaerobic conditions. The field-scale remediation, predicated on the in situ synthesis of Fe-OM association, effectively reduced the bioavailable Cd concentration in the soil from 0.91 mg/kg to 0.40 mg/kg. Concurrently, the Cd concentration in rice grains was lowered from 0.63 mg/kg to 0.15 mg/kg, thus falling beneath the national safety threshold. This study represents a significant advancement in the safe reclamation and utilization of agricultural soils with elevated geological Cd burdens.

Association of neutrophil extracellular traps burden with clinical and angiographic characteristics in patients with ST-elevation myocardial infarction

BackgroundThe precise triggers for atherosclerotic plaque rupture and the underlying pathophysiology of coronary thrombogenesis remain elusive. Polymorphonuclear neutrophils, particularly their formation of neutrophil extracellular traps (NETs), have garnered attention in the context of coronary atherothrombosis. This study sought to explore the association of NETs burden with clinical and angiographic characteristics in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) and thrombus aspiration (TA). MethodsFor this study, 336 consecutive STEMI patients undergoing pPCI were considered for TA. Aspirated thrombi underwent histological analysis and NETs quantification via immunohistochemistry. Potential associations of clinical variables and angiographic outcomes with NETs burden were assessed. ResultsManual TA was selectively performed in 72 cases with increased thrombotic burden, and 60 thrombi were suitable for analysis and included in the current study. Most thrombi specimens displayed lytic features (63%), and almost three out of four were identified as white thrombi. Increased NETs burden was significantly associated with prolonged pain-to-balloon time (>300 min), OR = 10.29 (95% CI 2.11–42.22, p = 0.001), and stress-induced hyperglycemia OR = 6.58 (95% CI 1.23–52.63, p < 0.01) after multivariate regression analysis. Additionally, distal embolization, and left ventricular ejection fraction ≤40% were more frequent among patients with an elevated NETs burden OR = 16.9 (95% CI 4.23–44.52, p < 0.01) and OR = 3.2 (95% CI 1.05–12.1, p = 0.05), respectively. ConclusionElevated NETs burden in STEMI thrombi may be due to delayed reperfusion and stress-induced hyperglycemia, and it is associated with an increased risk of distal embolization and lower left ventricular ejection fraction. Further research is needed to elucidate the role of NETs as a potential therapeutic target in acute atherothrombosis.

Elevated inflammatory burden index increases mortality in adults with chronic inflammatory airway diseases: a nationwide cohort study

ObjectiveThe objective of this study was to investigate the potential association between the inflammatory burden index (IBI) and the prevalence of chronic inflammatory airway diseases (CIAD), as well as mortality rates among individuals diagnosed with CIAD.MethodsParticipants were sourced from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2010. The IBI was calculated using the formula: IBI = C-reactive protein * neutrophils / lymphocytes. CIAD comprised self-reported asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). Mortality outcomes, including all-cause and respiratory disease mortality, were determined through linked data from the National Death Index (NDI) up to December 2019.ResultsA total of 27,495 adults were included. IBI was divided into quartiles, with the lowest quartile as the reference group. After adjusting for confounding variables, a positive correlation was observed between higher IBI and increased prevalence of total CIAD (OR = 1.383 [1.215–1.575]), asthma (OR = 1.267 [1.096–1.465]), chronic bronchitis (OR = 1.568 [1.263–1.946]), and COPD (OR = 1.907 [1.311–2.774]). Over a median follow-up of 12.33 [9.92-16.00] years, there were 1221 deaths from all causes and 220 deaths from respiratory disease among 4499 patients with CIAD. Following multivariate adjustments, the fourth quartile was significantly associated with increased risk of all-cause mortality (HR = 2.227 [1.714–2.893]) and respiratory disease mortality (HR = 2.748 [1.383–5.459]) compared to the first quartile of IBI in CIAD participants. Moreover, variable importance analysis using a random survival forest model demonstrated the significance of IBI in predicting mortality from both all-cause and respiratory diseases.ConclusionIBI exhibited an association with the prevalence of CIAD, with higher IBI levels correlating with elevated all-cause and respiratory disease mortality among individuals with CIAD.

Deterioration of neuroimmune homeostasis in Alzheimer’s Disease patients who survive a COVID-19 infection

Growing evidence has implicated systemic infection as a significant risk factor for the development and advancement of Alzheimer’s disease (AD). With the emergence of SARS-CoV-2 (COVID-19) and the resultant pandemic, many individuals from the same aging population vulnerable to AD suffered a severe systemic infection with potentially unidentified long-term consequences for survivors. To study the impact of COVID-19 survival on the brain’s intrinsic immune system in a population also suffering from AD, we profiled post-mortem brain tissue from patients in the UF Neuromedicine Human Brain and Tissue Bank with a diagnosis of AD who survived a COVID-19 infection (COVID-AD) and contrasted our findings with AD patients who did not experience a COVID-19 infection, including a group of brain donors who passed away before arrival of SARS-CoV-2 in the United States. We assessed disease-relevant protein pathology and microglial and astrocytic markers by quantitative immunohistochemistry and supplemented these data with whole tissue gene expression analysis performed on the NanoString nCounter® platform. COVID-AD patients showed slightly elevated Aβ burden in the entorhinal, fusiform, and inferior temporal cortices compared to non-COVID-AD patients, while tau pathology burden did not differ between groups. Analysis of microglia revealed a significant loss of microglial homeostasis as well as exacerbated microgliosis in COVID-AD patients compared to non-COVID-AD patients in a brain region-dependent manner. Furthermore, COVID-AD patients showed reduced cortical astrocyte numbers, independent of functional subtype. Transcriptomic analysis supported these histological findings and, in addition, identified a dysregulation of oligodendrocyte and myelination pathways in the hippocampus of COVID-AD patients. In summary, our data demonstrate a profound impact of COVID-19 infection on neuroimmune and glial pathways in AD patients persisting for months post-infection, highlighting the importance of peripheral to central neuroimmune crosstalk in neurodegenerative diseases.

Longitudinal assessment of glymphatic changes following mild traumatic brain injury: Insights from perivascular space burden and DTI-ALPS imaging.

Traumatic brain injury (TBI) even in the mild form may result in long-lasting post-concussion symptoms. TBI is also a known risk to late-life neurodegeneration. Recent studies suggest that dysfunction in the glymphatic system, responsible for clearing protein waste from the brain, may play a pivotal role in the development of dementia following TBI. Given the diverse nature of TBI, longitudinal investigations are essential to comprehending the dynamic changes in the glymphatic system and its implications for recovery. In this prospective study, we evaluated two promising glymphatic imaging markers, namely the enlarged perivascular space (ePVS) burden and Diffusion Tensor Imaging-based ALPS index, in 44 patients with mTBI at two early post-injury time points: approximately 14 days (14Day) and 6-12 months (6-12Mon) post-injury, while also examining their associations with post-concussion symptoms. Additionally, 37 controls, comprising both orthopedic patients and healthy individuals, were included for comparative analysis. Our key findings include: (1) White matter ePVS burden (WM-ePVS) and ALPS index exhibit significant correlations with age. (2) Elevated WM-ePVS burden in acute mTBI (14Day) is significantly linked to a higher number of post-concussion symptoms, particularly memory problems. (3) The increase in the ALPS index from acute (14Day) to the chronic (6-12Mon) phases in mTBI patients correlates with improvement in sleep measures. Furthermore, incorporating WM-ePVS burden and the ALPS index from acute phase enhances the prediction of chronic memory problems beyond socio-demographic and basic clinical information. ePVS burden and ALPS index offers distinct values in assessing glymphatic structure and activity. Early evaluation of glymphatic function could be crucial for understanding TBI recovery and developing targeted interventions to improve patient outcomes.

Mortality risk and burden of sudden cardiac arrest associated with hot nights, heatwaves, cold spells, and non-optimum temperatures in 0.88 million patients: An individual-level case-crossover study

Sudden cardiac arrest (SCA) is a global health concern, imposing a substantial mortality burden. However, the understanding of the impact of various extreme temperature events, when accounting for the effect of daily average temperature on SCA, remains incomplete. Additionally, the assessment of SCA mortality burden associated with temperatures from an individual-level design is limited. This nationwide case-crossover study collected individual SCA death records across all (2844) county-level administrative units in the Chinese Mainland from 2013 to 2019. Four definitions for hot nights and ten for both cold spells and heatwaves were established using various temperature thresholds and durations. Conditional logistic regression models combined with distributed lag nonlinear models were employed to estimate the cumulative exposure-response relationships. Based on 887,662 SCA decedents, this analysis found that both hot nights [odds ratio (OR): 1.28; attributable fraction (AF): 1.32 %] and heatwaves (OR: 1.40; AF: 1.29 %) exhibited significant added effects on SCA mortality independent of daily average temperatures, while cold spells were not associated with an elevated SCA risk after accounting for effects of temperatures. Cold temperatures [below the minimum mortality temperature (MMT)] accounted for a larger mortality burden than high temperatures (above the MMT) [AF: 12.2 % vs. 1.5 %]. Higher temperature-related mortality risks and burdens were observed in patients who experienced out-of-hospital cardiac arrest compared to those with in-hospital cardiac arrest. This nationwide study presents the most compelling and comprehensive evidence of the elevated mortality risk and burden of SCA associated with extreme temperature events and ambient temperatures amid global warming.

Integrative genome-centric metagenomics for surface water surveillance: Elucidating microbiomes, antimicrobial resistance, and their associations

Surface water ecosystems are intimately intertwined with anthropogenic activities and have significant public health implications as primary sources of irrigation water in agricultural production. Our extensive metagenomic analysis examined 404 surface water samples from four different geological regions in Chile and Brazil, spanning irrigation canals (n = 135), rivers (n = 121), creeks (n = 74), reservoirs (n = 66), and ponds (n = 8). Overall, 50.25 % of the surface water samples contained at least one of the pathogenic or contaminant bacterial genera (Salmonella: 29.21 %; Listeria: 6.19 %; Escherichia: 35.64 %). Furthermore, a total of 1,582 antimicrobial resistance (AMR) gene clusters encoding resistance to 25 antimicrobial classes were identified, with samples from Brazil exhibiting an elevated AMR burden. Samples from stagnant water sources were characterized by dominant Cyanobacteriota populations, resulting in significantly reduced biodiversity and more uniform community compositions. A significant association between taxonomic composition and the resistome was supported by a Procrustes analysis (p < 0.001). Notably, regional signatures were observed regarding the taxonomic and resistome profiles, as samples from the same region clustered together on both ordinates. Additionally, network analysis illuminated the intricate links between taxonomy and AMR at the contig level. Our deep sequencing efforts not only mapped the microbial landscape but also expanded the genomic catalog with newly characterized metagenome-assembled genomes (MAGs), boosting the classification of reads by 12.85 %. In conclusion, this study underscores the value of metagenomic approaches in surveillance of surface waters, enhancing our understanding of microbial and AMR dynamics with far-reaching public health and ecological ramifications.

Premature ventricular complexes after catheter ablation for atrial fibrillation: Accounting for regression to the mean.

Prior studies have indicated that the frequency of premature ventricular complexes (PVC) increases after catheter ablation for atrial fibrillation (AF). However, these studies have primarily focused on patients whose PVC burden increased rather than including the full spectrum of outcomes. We performed a single-center retrospective cohort study of consecutive patients who underwent first-time AF ablation from 1/2018 to 12/2022 for paroxysmal or persistent AF and had both preablation and postablation rhythm monitoring within 6 months of the procedure. Patients were excluded if they had prior AF or PVC ablation or were prescribed a class I or III antiarrhythmic medication. Among 2945 patients who underwent AF ablation during the study period, 130 patients underwent first-time AF ablation and received both pre and post ambulatory monitoring. The median PVC burden before ablation was <1%. Most patients (63%) had no change in PVC burden after AF ablation compared with preablation, and patients who had an increase in PVC burden were offset by those with reductions in PVCs. A paired analysis pre- and post-AF ablation showed no significant change in PVC burden (p = .495). Although an elevated PVC burden after AF ablation may be seen clinically, the majority of patients have no change in burden. Studies that suggest an increase in PVC burden after AF ablation may suffer from incomplete sample selection and thus omit the important effect of regression to the mean.

Deciphering the prognostic role of endoplasmic reticulum stress in lung adenocarcinoma: integrating prognostic prediction and immunotherapy strategies

Endoplasmic reticulum stress (ERS) is a critical factor influencing lung adenocarcinoma (LUAD) progression and patient outcomes. In this study, we analyzed gene expression data from LUAD samples sourced from The Cancer Genomic Atlas and Gene Expression Omnibus databases. Utilizing advanced statistical methods including LASSO and Cox regression, we developed a ERS-associated signature (ERAS) based on ten ERS-related genes. This model stratified patients into high- and low-risk groups, with the high-risk group exhibiting decreased survival rates, elevated tumor mutational burden, and heightened chemotherapy sensitivity. Additionally, we observed lower immune and ESTIMATE scores in the high-ERAS group, indicating a potentially compromised immune response. Experimental validation through quantitative real-time polymerase chain reaction confirmed the utility of our model. Furthermore, we constructed a nomogram to predict 1-, 3-, and 5-year survival rates, providing clinicians with a valuable tool for personalized patient management. In conclusion, our study demonstrates the efficacy of the ERAS in identifying high-ERAS LUAD patients, offering promising implications for improved prognostication and treatment strategies.

Prognostic significance of negative lymph node count in microsatellite instability-high colorectal cancer

BackgroundMicrosatellite instability-high (MSI-H) tumors, with elevated tumor mutational burden and expression of neoantigens, represent a distinct immune-activated subpopulation in colorectal cancer (CRC), characterized by strong lymph node reaction, locally advanced tumor and higher total lymph nodes harvested (TLN), but less metastatic lymph nodes and fewer incidence of III-IV stage. Host immune response to tumor and lymph nodes may be an important prognostic factor. However, N stage and LNR (Lymph-Node Ratio) have limitations in predicting the prognosis of MSI-H patients. Negative lymph node count (NLC) provided a more precise representation of immune activation status and extent of tumor metastasis. The study aims to detect prognostic significance of NLC in MSI-H CRC patients, and compare it with N stage, TLN and LNR.MethodsRetrospective data of 190 consecutive MSI-H CRC patients who received curative resection were collected. Survival analyses were performed using the Kaplan–Meier method. Clinicopathological variables including NLC, N stage, TLN and LNR were studied in univariate and multivariate COX regression analyses. ROC (receiver operating characteristic curve) and concordance index were employed to compare the differences in predictive efficacy between NLC, N stage, TLN and LNR.ResultsPatients with increased NLC experienced a significantly improved 5-years DFS and OS in Kaplan–Meier analysis, univariate analysis, and multivariate analysis, independent of potential confounders examined. Increased NLC corresponded to elevated 5-years DFS rate and 5-years OS rate. AUC (area under curve) and concordance index of NLC in DFS and OS predicting were both significantly higher than N stage, TLN and LNR.ConclusionsNegative lymph node is an important independent prognostic factor for MSI-H patients. Reduced NLC is associated with tumor recurrence and poor survival, which is a stronger prognostic factor than N stage, TLN and LNR.

O-081 Navigating the crossroads: unraveling predictors for treatment discontinuation in couples pursuing assisted reproduction: findings from a 2-year prospective study

Abstract Study question What are the medical, individual, relationship, and clinic-related factors associated with fertility treatment discontinuation ? Summary answer Insurance status and medication use by the partner emerged as primary predictors for treatment discontinuation, while emotional burden and cost were the leading reasons cited. What is known already Despite advancements in assisted reproduction, the arduous nature of fertility treatments prompts 20 to 30% of couples to discontinue before pregnancy, even with a favorable prognosis and financial means. Whereas the World Health Organization deems treatment compliance critical for effectiveness, fundamental knowledge on fertility treatment compliance is lacking. Existing retrospective studies attribute discontinuation to the physical and psychological burdens of treatment and relationship strain. However, understanding the precise nature of psychological and relational issues influencing this decision remains limited. Additionally, previous research has overlooked patient and clinic factors related to discontinuation, hindering professionals in supporting couples through this process. Study design, size, duration A 2-year prospective study with a correlational design. The sample included 310 couples (35 same-gender/sex couples) pursuing assisted reproduction in Canada or the United States. Data were collected between December 2019 and November 2023. Participants/materials, setting, methods Couples seeking assisted reproductive services within six months of their initial visit to a fertility clinic were recruited through social media and affiliated fertility clinics. Both partners completed online questionnaires evaluating sociodemographics, medical and treatment history, psychological and relationship functioning, and their perception of patient-centered care at baseline. Follow-up assessments occurred at 6, 12, 18, and 24 months. Treatment status (ongoing, terminated due to pregnancy) and reasons for discontinuation were also recorded at each follow-up. Main results and the role of chance To identify the primary predictors of treatment discontinuation, we conducted survival analyses using sociodemographic variables (age, relationship duration, income, insurance coverage), medical and treatment history (infertility duration, medication side effects), psychological (depression, anxiety symptoms, quality of life, distress tolerance, attachment style), relationship (satisfaction, dyadic coping, commitment), and patient-centered care (communication, involvement in decisions, information accessibility) data at baseline for both partners (person to be carrying the pregnancy and their partner). Variables were initially tested separately (p &amp;lt; .05), and significant predictors were included in a multivariate model. In individual analyses, couples whereby the partner did not have insurance or was using anxiety/mood medication were more likely to discontinue at some point during the study. Couples in which the person to be carrying the pregnancy reported higher attachment avoidance, lower relationship commitment, or less dyadic coping were also more likely to discontinue during the study. In the comprehensive model, only the partner’s insurance and medication use predicted discontinuation. The most frequently cited reasons for discontinuation were the emotional burden of treatment (43.6%) and cost (43.7%), followed by physical discomfort (31.4%), loss of hope regarding treatment (33.3%), reasons related to services in clinics (28.6%), and personal circumstances impeding treatment (27.5%). Limitations, reasons for caution Given the correlational study design, causation cannot be inferred between identified predictors and treatment discontinuation. The 2-year study duration also limits capturing later discontinuations. Predictors were assessed at baseline only, potentially differing across treatment stages. Finally, 2SLGBTQ+ couples experiencing social infertility are underrepresented in the sample. Wider implications of the findings These findings underscore the importance of addressing insurance accessibility and psychological factors in fertility treatment support. Elevated emotional burden and cost as prominent discontinuation reasons highlight the need for comprehensive, affordable care and emotional support in fertility clinics to improve overall patient experience and outcomes. Trial registration number n/a

Machine learning enables pan-cancer identification of mutational hotspots at persistent CTCF binding sites.

CCCTC-binding factor (CTCF) is an insulator protein that binds to a highly conserved DNA motif and facilitates regulation of three-dimensional (3D) nuclear architecture and transcription. CTCF binding sites (CTCF-BSs) reside in non-coding DNA and are frequently mutated in cancer. Our previous study identified a small subclass of CTCF-BSs that are resistant to CTCF knock down, termed persistent CTCF binding sites (P-CTCF-BSs). P-CTCF-BSs show high binding conservation and potentially regulate cell-type constitutive 3D chromatin architecture. Here, using ICGC sequencing data we made the striking observation that P-CTCF-BSs display a highly elevated mutation rate in breast and prostate cancer when compared to all CTCF-BSs. To address whether P-CTCF-BS mutations are also enriched in other cell-types, we developed CTCF-INSITE-a tool utilising machine learning to predict persistence based on genetic and epigenetic features of experimentally-determined P-CTCF-BSs. Notably, predicted P-CTCF-BSs also show a significantly elevated mutational burden in all 12 cancer-types tested. Enrichment was even stronger for P-CTCF-BS mutations with predicted functional impact to CTCF binding and chromatin looping. Using in vitro binding assays we validated that P-CTCF-BS cancer mutations, predicted to be disruptive, indeed reduced CTCF binding. Together this study reveals a new subclass of cancer specific CTCF-BS DNA mutations and provides insights into their importance in genome organization in a pan-cancer setting.