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PubMed2026

Changes in heroin-related ambulance attendances following the introduction of a medically supervised injecting room in Victoria, Australia.

BACKGROUND: Injecting drug use contributes significantly to morbidity, mortality and broader social harms globally. Supervised Injecting Facilities (SIFs) are harm reduction interventions that reduce overdose risk and facilitate access to health services for marginalised individuals. While international evidence supports the effectiveness of SIFs, Australian population-level surveillance data quantifying their impact on emergency medical service utilisation remain limited. METHODS: Using data from the National Ambulance Surveillance System, we conducted a retrospective, interrupted time series analysis of heroin-related ambulance attendances within the local catchment of the Medically Supervised Injecting Room (MSIR) between January 2015 and December 2023. Supplementary analysis included comparisons with central Melbourne suburbs and the broader state of Victoria. Key intervention timepoints, including the opening of the MSIR on 30 June 2018, expansion of its operating hours in July 2019, and the COVID-19 pandemic from April 2020 to October 2021, were examined to assess changes in heroin-related attendances over time. Segmented regression models were used to assess changes in heroin-related ambulance attendance trends over time. RESULTS: At the time the MSIR opened, the model-predicted heroin-related ambulance attendance rate within the MSIR catchment was 123 per 100,000 population per month, equivalent to approximately 48 heroin-related ambulance attendances per month. Prior to implementation, the attendance rate was increasing by an estimated 0.74 per 100,000 population per month. Following the opening of the MSIR, the previously increasing trajectory reversed, with ambulance attendance rates declining by approximately 2.3 per 100,000 population per month relative to the pre-intervention trend. By the end of the study period (December 2023), the predicted monthly heroin-related ambulance attendance rate had declined to 36 per 100,000 population (approximately 14 attendances per month), representing an overall reduction of 70.7% from the time of MSIR implementation. These reductions persisted throughout the COVID-19 lockdown period and were sustained after restrictions lifted. Supplementary analysis showed no comparable reductions in the central Melbourne region or the remainder of Victoria. CONCLUSIONS: The introduction of the MSIR in Richmond was associated with a sustained reduction in heroin-related ambulance attendances within its catchment area. These findings provide strong population-level evidence that SIFs reduce acute heroin-related harms requiring emergency ambulance response, reinforcing their role as an effective harm reduction strategy within the Australian context.

Humans↗
PubMed2026

Navigating Social Media: Balancing Connectivity With Media Literacy to Combat Misinformation and Protect Mental Well-Being.

BACKGROUND: The pervasive use of social media has created a complex digital ecosystem where high connectivity coexists with significant challenges, including the rapid spread of misinformation, particularly regarding mental health, and documented negative impacts on psychological well-being. Platform architectures designed for engagement maximization have been identified as central factors in both issues. OBJECTIVE: This paper critically analyzes the interconnected relationships between social media use, misinformation dissemination, and mental health impacts, with particular attention to psychiatric misinformation across diagnostic categories (e.g., depression, anxiety, ADHD). A primary objective is to evaluate the potential of advanced critical digital literacy frameworks to serve as protective mechanisms against these dual threats. METHODS: A systematic search was conducted following PRISMA 2020 guidelines across APA PsycInfo, PubMed, JSTOR, and Google Scholar for literature published between January 2018 and March 2026 (updated from the original 2023 search). The search yielded 2672 records. After removing 624 duplicates, 2048 records underwent title and abstract screening, with 1802 excluded. The remaining 246 full-text articles were assessed for eligibility, resulting in 86 studies included in the final qualitative synthesis. Inter-rater reliability was established (Cohen's κ = 0.82). Quality assessment was conducted using the Joanna Briggs Institute Checklist, AXIS, and CASP tools, with findings weighted by methodological quality. A thematic analysis was undertaken to synthesize findings. RESULTS: The analysis reveals that core architectural features of social media platforms, algorithmic curation and engagement-based metrics, simultaneously foster environments ripe for misinformation spread and contribute to psychological distress, including anxiety, depression, and harmful social comparison. Psychiatric misinformation specifically (e.g., inaccurate claims about treatment effectiveness, diagnostic criteria, and medication side effects) represents a growing concern, particularly on image- and video-based platforms. The findings indicate that conventional media literacy approaches focused solely on fact-checking are insufficient. Instead, a critical digital literacy framework encompassing algorithmic awareness, data literacy, and emotional awareness is essential for building user resilience, with evidence from high-quality systematic reviews supporting this approach. CONCLUSIONS: Navigating the complexities of modern social media requires an integrated approach combining "pedagogies of play" for experiential skill development with advocacy for structural change (e.g., algorithmic transparency, well being by design principles). This dual strategy empowers individual users to critically engage with digital content while advocating for ethical platform design, thereby safeguarding both mental well-being and democratic discourse. Implications for educators, mental health professionals (including competencies for addressing patient encounters with psychiatric misinformation), policymakers, and platform designers are discussed.

Humans↗
PubMed2026

Bivalirudin Versus Heparin in Low and Non-Low Bleeding Risk Patients Undergoing Primary PCI for STEMI: The BRIGHT-4 Trial.

BACKGROUND: In the BRIGHT-4 trial, among 6,016 patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) with a radial artery approach, procedural anticoagulation with bivalirudin plus a post-PCI high-dose infusion for 2 to 4 hours reduced the 30-day primary composite outcome of all-cause death or Bleeding Academic Research Consortium (BARC) types 3 to 5 bleeding, as well as death and bleeding individually, compared with heparin monotherapy. OBJECTIVES: We sought to determine whether the benefits of bivalirudin apply principally to patients who are at low bleeding risk (LBR) as well as non-LBR. METHODS: In a prespecified analysis from BRIGHT-4, outcomes were examined by baseline bleeding risk, with LBR defined as a CRUSADE score <30. RESULTS: At baseline, 4,581 patients (76.1%) were categorized as LBR. Non-LBR patients had higher rates of the 30-day primary endpoint (8.6% vs 2.2%; HR: 4.08 [95% CI: 3.14-5.31]; P < 0.0001), driven by both greater mortality and BARC types 3 to 5 bleeding. In non-LBR patients, the primary outcome occurred in 8.1% of patients randomized to bivalirudin vs 9.2% of those randomized to heparin (difference: -1.1% [95% CI: -4.0% to 1.8%]; HR: 0.88 [95% CI: 0.62-1.26]). In LBR patients, the primary outcome occurred in 1.4% of patients randomized to bivalirudin vs 2.9% of those randomized to heparin (difference: -1.5% [95% CI: -2.3% to -0.6%]; HR: 0.49 [95% CI: 0.32-0.75]) (Pabsolute interaction = 0.81; Prelative interaction = 0.04). The effects of bivalirudin compared with heparin in reducing all-cause death were as robust in LBR patients compared with non-LBR patients (Pabsolute interaction = 0.67; Prelative interaction = 0.06). CONCLUSIONS: Among patients with STEMI undergoing primary PCI with radial artery access, procedural anticoagulation with bivalirudin plus a high-dose post-PCI infusion for 2 to 4 hours reduced the 30-day risk of all-cause death and major bleeding in patients at low bleeding risk as well as in patients at higher-risk of bleeding. (Bivalirudin With Prolonged Full Dose Infusion Versus Heparin Alone During Emergency PCI [BRIGHT-4; NCT03822975]).

Humans↗
PubMed2026

Occlusion site and outcomes in intra-arterial tenecteplase after successful endovascular therapy: a secondary analysis of the ANGEL-TNK trial.

BACKGROUND: Endovascular thrombectomy achieves macroreperfusion in large vessel occlusion (LVO) stroke, but only one-quarter of patients had excellent functional outcome. Adjunct intra-arterial (IA) tenecteplase could further improve the treatment effect, yet its efficacy across internal carotid artery (ICA) versus middle cerebral artery (MCA) M1/M2 occlusion remains unclear. OBJECTIVE: To evaluate whether IA tenecteplase improves 90-day functional outcomes in LVO patients stratified by occlusion site (ICA, MCA M1, MCA M2). METHODS: Prespecified secondary analysis of the ANGEL-TNK trial (multicenter, randomized, open-label, blinded endpoint) in 19 Chinese stroke centers. Participants were enrolled who had anterior circulation LVO, 4.5-24&#x2009;hours from symptom onset, and CT angiography (CTA)/magnetic resonance angiography (MRA)-proven ICA, M1, or M2 occlusion. INTERVENTION: Randomization (1:1) to IA tenecteplase (0.125&#x2009;mg/kg) or standard medical management after expanded Thrombolysis in Cerebral Infarction (eTICI) 2b50-3 reperfusion. MAIN OUTCOME MEASURE: The primary outcome was the rate of 90-day modified Rankin Scale (mRS) 0-1. RESULTS: There were 256 patients in the trial, including 71 (27.7%) ICA, 122 (47.6%) MCA M1, and 62 (24.2%) MCA M2. ICA occlusion patients treated with IA tenecteplase had higher rates of 90-day mRS 0-1 (39.4% vs 13.2%; relative risk (RR) 2.99; 95%&#x2009;CI 1.51 to 5.96; p=0.002) and mRS 0-3 (54.5% vs 42.1%; RR 1.30; p=0.048) versus controls, with a significant shift toward better mRS scores (median 3 (IQR 1-4) vs 4 (2-6); odds ratio (OR) 2.26; p<0.001). Post hoc analysis showed higher eTICI progression in ICA patients (51.5%) versus MCA M1 (37.9%) and M2 (25.7%). IA tenecteplase had a lower any intracranial hemorrhage within 48 hours in ICA patients (15.2% vs 39.5%; RR 0.38; p<0.001) compared with standard medical management. No significant benefits were observed in the MCA M1/M2 subgroups, and interaction effects were significant between ICA and MCA segments for functional outcomes and safety. CONCLUSIONS AND RELEVANCE: IA tenecteplase had a better functional outcome and lower hemorrhage risk in ICA occlusion compared with standard medical management but not in MCA M1/M2. Occlusion site is a critical determinant of response to IA tenecteplase. A pooled analysis of IA tenecteplase stratified by occlusion site strata is warranted.

Humans↗
PubMed2026

Second-Generation ELZA-sub400 Protocol: Individualized High-Fluence Cross-Linking for Ultra-Thin Keratoconus Corneas.

PURPOSE: To evaluate the safety and efficacy of a second-generation individualized corneal cross-linking (CXL) protocol (ELZA-sub400) using high-fluence UV-A irradiation in ultrathin ectatic corneas. DESIGN: Retrospective, single-center, consecutive interventional case series. METHODS: Twenty-nine eyes of 24 patients with progressive keratoconus or post-LASIK ectasia and a post-soak intraoperative thinnest stromal thickness <400 &#xb5;m were included. After epithelial removal and riboflavin soaking, continuous UV-A irradiation (365 nm) at 3 or 9 mW/cm&#xb2; was delivered with total fluence titrated up to 10 J/cm&#xb2; based on intraoperative ultrasound pachymetry and a previously published nomogram targeting an uncross-linked stromal margin of approximately 70 &#xb5;m above the endothelium. Outcomes were assessed at baseline and up to 12 months using corrected distance visual acuity (CDVA) and corneal parameters measured using Scheimpflug tomography and anterior segment OCT (AS-OCT) with Placido-based topography. The main outcome measure was the proportion of eyes without progression at 12 months, defined as <1.0 D increase in maximum keratometry (Kmax). Secondary outcomes included changes in CDVA, refraction, Kmax, stromal thickness, demarcation line depth, densitometry, and safety parameters. RESULTS: At 12 months, 22/29 eyes (76%; 95% CI, 57.9%-87.8%) met the nonprogression criterion. Mean change in Kmax was -0.77 &#xb1; 5.10 D (95% CI, -2.71 to 1.17; P = .418). Mean demarcation line-to-anterior stroma distance was 205 &#xb1; 64 &#xb5;m (95% CI, 180.7-229.3), and demarcation line-to-endothelium distance was 64 &#xb5;m (IQR, 49-152). All demarcation lines remained within the stromal layer; 15/29 eyes (51.7%) had a demarcation line located &#x2264;70 &#xb5;m from the endothelium. Median CDVA changed from 0.10 to 0.32 logMAR (P = .142). Minimum stromal thickness showed a median change of -4.0 &#xb5;m (P = .309). No significant change was observed in densitometry, and no eye developed deep stromal haze or endothelial decompensation. CONCLUSIONS: Second-generation ELZA-sub400 CXL halted ectasia progression in 76% of ultrathin corneas at 12 months and was associated with an acceptable short-term safety profile, including stromal-confined demarcation line formation and no observed endothelial decompensation. The numerical decline in spectacle CDVA observed in this severely affected cohort did not reach statistical significance but is clinically important and warrants confirmation in larger prospective studies.

Humans↗
PubMed2026

Genome-wide scans reveal candidate genes associated with wing morph differentiation in Tetrix japonica.

Wing dimorphism is an important dispersal-related trait in insects, but its genomic basis remains poorly understood in pygmy grasshoppers. Here, we integrated genome-wide single-nucleotide polymorphism (SNP) analyses, population structure inference, selection scans, and functional annotation to investigate genomic differentiation between long- and short-winged Tetrix japonica. Principal component analysis (PCA), ADMIXTURE, and phylogenetic analyses revealed weak genome-wide separation between morphs, indicating differentiation on a largely shared genetic background. Genome-wide scans based on the fixation index (FST), nucleotide diversity ratios, and Tajima's D, using 50-kb non-overlapping windows and empirical top-5% outlier thresholds, identified multiple candidate regions across seven chromosomes. The broader long- and short-winged candidate sets spanned 9.35&#xa0;Mb and 9.37&#xa0;Mb and directly overlapped 82 and 77 genes, respectively. Candidate genes were associated with signaling/hormone regulation, membrane transport, metabolism, cytoskeletal organization, extracellular matrix structure, and development. Short-winged candidate genes were significantly enriched for ABC-type transporter activity and ATP hydrolysis activity. Because all individuals originated from a single laboratory-maintained population with weak genome-wide structure, these regions should be regarded as candidate loci from a screening-stage analysis that require validation in independent populations and by functional assays, rather than as confirmed targets of selection.

Animals↗
PubMed2026

Analyzing salinity tolerance in grass carp (Ctenopharyngodon idella): Insights from genome-wide association study and genomic selection.

Grass carp (Ctenopharyngodon idella) is one of the most widely cultured freshwater fish species globally. However, the expansion of its farming scale faces severe limitation owing to freshwater scarcity; therefore, the development of strains with greater salinity tolerance is key for expanding production using brackish water resources. To investigate the genetic basis of salinity tolerance in grass carp, a genome-wide association study (GWAS) was conducted using 200 individuals representing extreme phenotypes, namely salinity-tolerant and salinity-sensitive groups. In total, 17 single nucleotide polymorphisms (SNPs) related to salinity tolerance were detected, which were distributed across 11 chromosomes. Through gene annotation, 38 candidate genes were obtained from these loci. Enrichment analysis revealed these candidate genes are primarily implicated in key biological processes, including osmotic regulation, energy metabolism, and stress responses. Analyses of different SNP densities revealed that the 5&#xa0;K SNP density panel can balance prediction accuracy and computational efficiency. The BayesA model achieved the highest prediction accuracy under the GWAS_Evenly selection strategy, with substantial reductions in mean absolute error and mean square error. This study reveals the genetic mechanisms of salinity tolerance in grass carp, which might be optimized through genomic selection, and provides insights for selectively breeding new varieties with greater salinity tolerance.

Animals↗
PubMed2026

Genomic characterization and pathogenicity of ruminant Listeria monocytogenes isolates in a murine oral infection model.

Listeria monocytogenes is a major foodborne pathogen; its ruminant isolates display zoonotic characteristics, causing similar clinical signs in humans, including abortion and encephalitis. However, data on whole genome sequencing and pathogenicity of ruminant L. monocytogenes isolates remain sparse. This study aimed to analyze the genotypic characteristics of L. monocytogenes isolates from ruminants with listeriosis. Furthermore, we assessed the in vivo pathogenicity of four ruminant L. monocytogenes isolates, characterized via whole-genome sequencing-based genetic clustering, in orogastrically inoculated mice. The isolate LM18 (serotype 1/2b, ST224, SL6178) had the lowest lethal dose compared to the other three isolates including previous hypervirulence type (serotype 4b, ST1, SL1) and caused secondary bacteremia in lungs, with sustained bacterial loads in the spleen and liver. Genomic (listeria pathogenicity island -1 and -3) and virulence gene (actA and llsX) mutation analyses associated with virulence suggested from well-recognized studies could not elucidate the virulence of the isolates. SSI-1, which only exists in the isolate LM18 (serotype 1/2b, ST224, SL6178), may help L. monocytogenes survive in the gastrointestinal environment, thereby affecting its virulence. Further research should investigate the role of SSI-1 in the pathogenicity of L. monocytogenes. Moreover, additional studies utilizing larger datasets of ruminant isolates are required to validate our genotypic characterization and to obtain a comprehensive picture of further genotypic differences crucial for L. monocytogenes pathogenicity.

Animals↗
PubMed2026

Whole-Genome Deep Learning Predicts Chemotherapy Response in Colorectal Cancer.

Chemotherapy response in colorectal cancer (CRC) exhibits significant heterogeneity, with current clinical predictors failing to capture complex genomic determinants of resistance. We developed a hybrid deep learning framework integrating convolutional neural networks (CNNs) and bidirectional long short-term memory (BiLSTM) networks to analyze whole-genome somatic mutations, evolutionary conservation, chromatin accessibility, and 3D genome architecture in 2,546 TCGA patients. An attention mechanism identified predictive genomic regions. The model achieved an AUC of 0.92 (95% CI: 0.89-0.94) in cross-validation and 0.88 (95% CI: 0.85-0.91) in independent validation, outperforming clinical models (&#x394;AUC = +0.18, p < 0.001). Key predictors included non-coding variants in TP53, KRAS, and PIK3CA regulatory regions. Triple-positive patients (mutations in all 3 regions) had significantly worse progression-free survival (HR = 4.7, p < 0.001). Our framework enables accurate chemotherapy response prediction and reveals novel non-coding resistance mechanisms, advancing precision oncology in CRC.

Humans↗
PubMed2026

Draft genome sequence of Enterococcus casseliflavus strain MBBL_MP4 isolated from healthy bovine milk.

We report the draft genome sequence of Enterococcus casseliflavus MBBL_MP4, recovered from healthy bovine milk. The 3.45-Mbp genome assembly comprises 27 contigs and indicates low pathogenic potential, with no acquired antimicrobial resistance or known virulence genes. This genome provides a valuable resource for the genomic characterization of bovine-associated E. casseliflavus.

Enterococcus casseliflavus↗
PubMed2026

Efficacy of sodium-glucose cotransporter 2 inhibitors after acute myocardial infarction: Are the benefits limited to patients with diabetes? A systematic review and meta-analysis.

BACKGROUND: Acute myocardial infarction remains one of the leading causes of death worldwide. Recently, studies have focused on evaluating the effectiveness of SGLT2 inhibitors in this scenario. Objectives We aimed to perform a meta-analysis comparing the efficacy of SGLT2 inhibitors vs standard care. METHODS: We systematically searched PubMed, Embase, and Cochrane for randomized controlled trials (RCTs) and observational studies comparing patients with acute myocardial infarction using iSGLT2 inhibitors and standard care. Statistical analyses were conducted using R software (v 4.3.2) and a random-effects model was employed for all outcomes. RESULTS: A total of 31,378 patients were included, with 10,897 (34.7%) assigned to the SGLT2 inhibitor group. Among these studies, three were randomized controlled trials (RCTs). There was a significant difference in reduction of HF readmissions (OR 0.61; p&#xa0;<&#xa0;0.01), all-cause mortality (OR 0.62; p&#xa0;<&#xa0;0.01;) and stroke (OR 0.67; p&#xa0;<&#xa0;0.01;). However, there was no significant difference in cardiovascular death, rehospitalization for any cause and recurrence of acute MI. Meta regression and subgroup analysis showed a trend toward better outcomes in the diabetic and non-STEMI population. CONCLUSIONS: SGLT2 inhibitors were associated with lower HF rehospitalization, stroke, and all-cause mortality after acute MI, mainly in observational studies. Benefits appeared greater in diabetic and non-STEMI patients. Dedicated RCTs focusing on diabetic, particularly non-STEMI, populations are needed to confirm these findings. KEY POINTS: What is already known on this topic: SGLT2 inhibitors have demonstrated cardiovascular and renal benefits in patients with heart failure and type 2 diabetes mellitus. However, their role in the acute myocardial infarction (AMI) setting remains uncertain, particularly regarding post-AMI outcomes such as heart failure readmissions, mortality, and recurrent ischemic events, with current evidence derived from heterogeneous and predominantly observational studies. WHAT THIS STUDY ADDS: This meta-analysis, including over 31,000 patients, suggests that SGLT2 inhibitors are associated with reductions in heart failure readmissions, all-cause mortality, and stroke following AMI. These associations were more consistently observed in patients with type 2 diabetes and in non-ST-segment elevation myocardial infarction (NSTEMI) populations. However, randomized controlled trials showed neutral results, and the observed benefits were mainly driven by observational studies. Meaning: These findings should be interpreted as hypothesis-generating. While SGLT2 inhibitors may represent a potential therapeutic strategy in selected post-AMI populations, particularly patients with diabetes and NSTEMI, current evidence does not support routine early in-hospital initiation. Dedicated randomized trials specifically enrolling diabetic post-AMI patients are required to clarify optimal timing and clinical benefit.

Humans↗
PubMed2026

Complete mitochondrial genomes of eight cyclophyllidean tapeworms: genome pattern and phylogenetic analysis.

Cyclophyllidean tapeworms are widespread parasites of significant medical and veterinary importance. However, mitochondrial (mt) genomic resources for cyclophyllideans from China, particularly those recovered from wildlife hosts, remain comparatively limited. In this study, we sequenced and characterized the complete mt genomes of eight cyclophyllidean isolates collected from diverse wild and domestic hosts in China, including two Hymenolepis sp. isolates and two Raillietina sp. isolates from China, and four additional isolates of previously sequenced Taenia species. The circular mt genomes ranged from 13,387 to 14,021&#xa0;bp in length, encoding 36 typical genes with variable non-coding regions. Comparative analysis revealed highly conserved gene composition and mostly conserved mt architecture, with localized rearrangement patterns detected among the cyclophyllidean lineages examined. In particular, all sampled Taeniidae exhibited a consistent trnL1-trnS2 arrangement, whereas the examined non-Taeniidae families showed the trnS2-trnL1 arrangement, confirming and extending, across additional wildlife-associated isolates, a previously proposed family-associated gene-order marker within Cyclophyllidea. Phylogenetic analyses based on concatenated amino acid sequences of the 12 protein-coding genes placed the eight isolates within their expected families, in topologies broadly consistent with previous mitogenomic studies. These data provide additional Chinese mitogenomic references, especially for underrepresented wildlife-associated isolates, and support family-associated gene-order patterns in Cyclophyllidea.

Animals↗
PubMed2026

Assembly and Characterization of the First Complete Mitochondrial Genome of Tussilago farfara L.: Insights into Biological Functions and Phylogenetic Relationships within the Asteraceae Family.

Tussilago farfara L., a member of the Asteraceae family, is an economically valuable species due to its edible and medicinal properties. To elucidate the structural characteristics, genetic mechanisms, and evolutionary pathways of the organelle genomes of T. farfara, we sequenced, assembled, and annotated its mitochondrial genome for the first time. The complete mitochondrial genome of T. farfara spans 306,024&#xa0;bp and contains 33 mitochondrial protein-coding genes (PCGs), 3 rRNAs, and 22 tRNAs. Analysis of the nucleotide substitution rate and genetic diversity revealed that most mitochondrial genome genes may have undergone purifying selection, indicating a slow evolutionary rate and a relatively conserved genomic structure. We further identified 13 fragments of chloroplast-derived DNA integrated into the mitochondrial genome, evidencing intracellular gene transfer. Collinearity analysis showed that Arctium lappa shares the most extensive mitochondrial homologous sequences and the highest sequence similarity with T. farfara. Phylogenetic analysis based on the mitochondrial genome helped to clarify the evolutionary and taxonomic position of T. farfara within the Asteraceae family. The mitochondrial genome sequence of T. farfara provides a valuable genomic resource for species identification and for evolutionary studies within the Asteraceae family.

Genome, Mitochondrial↗
PubMed2026

Divergent trajectories of genome architecture and chromosome evolution in ferns and angiosperms.

Ferns and angiosperms represent the two largest vascular plant lineages but exhibit striking genomic and ecological contrasts. We investigated whether differences in genome size, chromosome architecture, GC content, and stomatal traits reveal divergent evolutionary trajectories between these lineages. We assembled the most comprehensive dataset to date, integrating genome size, chromosome number and size, GC content, and stomatal traits for over 1100 fern species and compared it with an extensive angiosperm dataset. Ferns exhibited markedly lower variability and c. 16-fold slower rates of chromosome size evolution than angiosperms. A persistent positive relationship between genome size and chromosome number in ferns suggests limited cytological post-polyploid diploidization. While ferns generally possess larger stomata, this difference disappears after accounting for genome size, indicating that nucleotypic constraints, rather than lineage-specific physiology, dictate stomatal dimensions. Both groups share a unimodal GC-genome size relationship peaking at c. 14 Gbp. Larger fern chromosomes imply lower genome-wide recombination rates, potentially limiting genetic reshuffling and adaptive potential. Our results highlight fundamentally divergent evolutionary trajectories, likely shaped by meiotic symmetry in ferns and meiotic asymmetry, possibly centromere drive, and post-polyploid diploidization in angiosperms, defining the functional and genomic landscapes of these lineages across deep evolutionary timescales.

Genome, Plant↗