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Biology subjects

Guo, X.

Publications and source records attributed to Guo, X..

At least 37 records · Page 2Linked to original sources

Patterns and correlates of invasive alien plant richness in China's abandoned croplands

Cropland abandonment is a widespread socio-ecological transition that can generate heterogeneous ecological outcomes, including opportunities for vegetation recovery as well as the accumulation of invasive alien plants (IAPs). Understanding broad-scale correlates of IAP richness in abandoned croplands is challenging because published studies differ in sampling design, spatial extent, and reporting detail. To provide an exploratory national-scale synthesis, we compiled literature-derived occurrence records of 57 IAP species reported from abandoned croplands across China and examined study-level recorded richness using generalized linear mixed models (GLMMs) with province as a random effect. Fourteen socio-economic and environmental predictors were screened for multicollinearity and standardized, and the number of Higher Education Institutions (HEIs) was included as a proxy for potential sampling-effort variation. Asteraceae accounted for 43.9% of recorded species, and more than 70% of taxa were classified as high-risk invaders (Levels 1-2). Recorded richness exhibited a pronounced southeast-northwest gradient, with higher values in economically developed coastal provinces. In the exploratory GLMM, regional GDP (IRR = 1.67, p < 0.05) and mean annual temperature (IRR = 1.49, p < 0.05) were positively associated with recorded richness, whereas other environmental, accessibility, soil, and sampling-effort variables showed no detectable associations. Model diagnostics indicated no evidence of overdispersion, zero inflation, or residual spatial autocorrelation. Given the heterogeneous nature of literature-derived data and the small number of study units, these results should be interpreted as broad-scale correlational patterns rather than causal drivers. The findings highlight regional socio-economic context and climatic conditions as key correlates of recorded IAP richness in abandoned croplands and provide an initial baseline for understanding invasion patterns in post-agricultural landscapes undergoing rapid land-use transitions..

ecology↗

Site-specific cholesterol depletion therapy for gastric cancer

Altered cholesterol metabolism is a recognized hallmark of cancer, but systemic modulation has not yet delivered significant clinical results. Accumulating evidence shows that cholesterol plays distinct roles across diverse cellular membranes, suggesting that site-specific modulation may produce superior therapeutic outcomes. Cholesterol is associated with gastric cancer (GC), but the mechanistic link is complex and no effective cholesterol-targeted therapy has been developed. Here, we report that cholesterol levels in GC cells are site-specifically elevated in the inner leaflet of the plasma membrane (IPM). This elevated IPM cholesterol constitutively activates Wnt-{beta}-catenin signaling to drive cell survival and proliferation. Mechanistically, Niemann-Pick C1-like 1 (NPC1L1), which is highly expressed in GC patient tissues and cell lines, acts as a cholesterol flippase to raise IPM cholesterol levels, facilitating ligand-independent {beta}-catenin signalosome formation. Ezetimibe, a clinically approved NPC1L1 inhibitor, blocks this flippase activity, lowers IPM cholesterol levels, and suppresses {beta}-catenin signaling. Ezetimibe treatment induces apoptosis in GC cells while sparing normal primary gastric epithelial cells, which exhibit low levels of NPC1L1 and IPM cholesterol. Collectively, these results suggest that site-specific modulation of cellular cholesterol is a viable approach to developing safe and effective therapies for cancers linked to local cholesterol elevation.

biochemistry↗

Pathogen context reshapes antimicrobial peptide generation

Antimicrobial peptides are a promising source of new anti-infective agents, but their discovery is limited by a practical bottleneck: selecting a small set of candidates to synthesize and test for a specific pathogen. Existing peptide generators can expand antimicrobial-like sequence space, but most leave pathogen specificity to predictors or filters after generation. Here, we use AMPHORA, a pathogen-conditioned sequence-structure generator, to build antimicrobial peptide libraries shaped by target context. AMPHORA couples a short-peptide representation model to latent-flow generation conditioned on target class, genome-derived features and strain-description text. In matched, partial and shuffled controls, pathogen context redirected generated peptide pools beyond broad activity labels, with the strongest effects when genome and text conditions were combined. Counterfactual generation from the same initial noise showed that strain descriptions primarily changed amino-acid choices, whereas genome-derived features contributed more strongly to predicted structural properties. Across species, AMPHORA produced target-dependent enrichment, and matched bacterial context shifted APEX-predicted potency-score distributions compared with class-only generation. The generated peptides remained diverse, novel and peptide-like by sequence and predicted-structure analyses. Collectively, our results establish pathogen context as an active design signal for antimicrobial peptide generation and provide a target-aware route to pre-synthesis library design.

bioinformatics↗

Super-Resolution Visual ProteomEx for Hard Tissues and Clinical Samples

Correlating nanoscale tissue architecture with unbiased molecular composition within the same specimen remains a fundamental challenge in spatial biology. Current spatial proteomics methods either lack the imaging resolution required to resolve nanoscale tissue architecture or achieve only limited proteome coverage, and untargeted approaches capable of deep protein identification have yet to be integrated with super-resolution imaging within a single workflow. Here, we present microProteomEx, an integrated platform that combines hydrogel-assisted tissue expansion with mass spectrometry-compatible fluorescence imaging, laser capture microdissection, and bottom-up proteomics to achieve simultaneous three-dimensional super-resolution imaging (effective lateral resolution down to [~]47 nm on conventional diffraction-limited microscopes) and spatially resolved proteomics at a scalable lateral resolution of 29-100 {micro}m (0.02-0.28 nL volumetric resolution). By optimizing fixation, protein anchoring, and a secondary re-embedding strategy, we extend the method to mechanically resilient tissues, including mouse kidney and heart, as well as to formalin-fixed, paraffin-embedded clinical specimens. We demonstrate single-glomerulus and single-plaque proteomics (450-1,000 proteins per structure), resolve proteomic differences between malignant melanoma and giant congenital melanocytic nevus in a rare pediatric case, and characterize the morphology-resolved molecular heterogeneity of cored versus diffuse amyloid-beta plaques in a mouse model of Alzheimers disease across two disease stages. microProteomEx establishes a broadly accessible framework for correlating tissue ultrastructure with deep spatial proteomics, with direct implications for disease biology, biomarker discovery, and precision medicine.

biochemistry↗

Client-server interfaces enable efficient agent-driven variant calling

BackgroundLarge language model (LLM) agents increasingly automate bioinformatics analyses, but most existing bioinformatics tools were built for standalone use by human experts. An agent driving such a tool must reason about its installation, configuration, and execution from documentation for human, spending many turns, tokens, and tool calls per result. How a method is exposed to an agent can therefore matter as much as the method itself. By designing agentic interfaces for these tools, agent can reduce such overhead and improve the reliability of agent-driven analyses. FindingsTo test this design, we re-architected Clair3, a widely used deep-learning-based long-read variant caller, into a client-server system, Clair3-Connect. The client performs all genomics related processing and holds the identifiable data. The server runs only neural-network inference, and the client sends only feature tensors to the server, while sample identifiers and genomic context remain on the client. The client exposes schema-defined agent-facing tools that an agent invokes through single structured calls. On an APOE diplotyping task, all 60 agent runs were correct. The agentic tools used 12K tokens in 3 turns, 6.8 to 14 times fewer tokens than the shell-driven baselines (81K-163K tokens), at about a quarter the wall-clock time and far more stably (4% versus 35% token usage variation). Dropping the pileup and phasing stages to keep the client light left SNP F1 within 0.1-0.3 points of standard Clair3 by 50x coverage, while mutual TLS and AES-256-GCM encryption added 7.2% to end-to-end runtime. ConclusionsRecasting an established algorithm as developer-built, agentic tools behind a secure client-server boundary makes it more efficient, reliable, and easier to deploy for an LLM agent than a third-party wrapper, which cannot recover the defaults and conventions only its developers know. Agentic interfaces should be a first-class deliverable of bioinformatics tool development.

bioinformatics↗

Ginsenoside Ro ameliorates diabetic cardiomyopathy by maintaining ciliary homeostasis and enhancing antioxidation

ObjectiveTo investigate and clarify the role of Ginsenoside Ro (GRo) in diabetic cardiomyopathy (DiaCM) and to elucidate the molecular mechanism by which GRo ameliorates DiaCM. Methods[circled1] The construct of type 2 diabetic mouse model. The bought C57BL/6 male mice were housed in a specific pathogen-free (SPF) animal facility and randomly divided into control, STZ (model), STZ + GRo, and control+GRo groups. The STZ (model) and STZ + GRo groups were fed a high-fat and high-glucose diet combined with intraperitoneal injection of streptozotocin (STZ). The control and control + GRo groups were fed a normal diet, while the control + GRo and STZ + GRo groups were treated with GRo via oral gavage. Then, all groups were evaluated for cardiac function and structure by small animal echocardiography and histological staining including hematoxylin and eosin (HE) and Massons trichrome staining to screen and confirm diabetic cardiomyopathy in mice. Finally, immunofluorescence staining of cilia in mouse heart tissue was performed to determine whether GRo inhibits abnormal ciliary growth. [circled2] The construct of cell models. First, the CCK-8 (Cell Counting Kit-8) assay was used to separately evaluate the cytotoxicity of GRo and the combination of TGF-{beta}1 and PA in myocardial fibroblasts and cardiomyocytes. Subsequently, mouse myocardial fibroblast lines (MCFs) were treated with transforming growth factor-beta 1 (TGF-{beta}1), and H9c2 cardiomyocytes were treated with palmitic acid (PA). Both cell types then received the GRo treatment. [circled3] Molecular and cellular testing. Firstly, we measured serum levels of cardiac injury markers (CK-MB, MYO, and TNNI3), glutathione (GSH), and malondialdehyde (MDA). Secondly, we examined the expression of myocardial fibrosis-related genes (Col1a1, etc.), myocardial hypertrophy markers (Nppa, etc.), cilia-specific genes (Pkd1, etc.), and oxidative stress-related genes (Nrf2, etc.) in both animal and cell samples by Western blotting and RT-qPCR. Finally, we used immunofluorescence staining of myocardial fibroblasts to detect cilia length and phalloidin staining of cardiomyocytes to measure their cross-sectional area. [circled4] The correlation mechanism. Firstly, the cilia-specific inhibitory drug HIP-4 was used to disrupt cilia homeostasis by inhibiting cilia growth. Secondly, small activating RNA (saRNA) was used to upregulate the Pkd1 gene to verify whether GRo exerts its anti-fibrotic effects through the inhibition of PC1. Results[circled1] Animal level. A diabetic cardiomyopathy mouse model was successfully established by combining STZ injection with a high-fat and high-glucose diet, and treatment with GRo significantly ameliorated the associated symptoms. [circled2] Cellular level. We successfully established a myocardial fibrosis model by treating myocardial fibroblasts with TGF-{beta}1, and a myocardial hypertrophy model by treating cardiomyocytes with PA. Immunofluorescence staining demonstrated that GRo significantly decreased cilia length in the fibrosis model, while phalloidin staining showed that GRo significantly attenuated the increase in cardiomyocyte cross-sectional area. [circled3] Molecular level. Compared with the model group, GRo treatment significantly reduced serum levels of cardiac injury markers (CK-MB, MYO and TNNI3), glutathione (GSH) and malondialdehyde (MDA). Western blotting and RT-qPCR analyses of both animal and cell samples revealed that GRo markedly alleviated indicators of myocardial fibrosis and hypertrophy, while also suppressing cilia-specific genes and oxidative stress-related genes. Overall, GRo significantly ameliorated the markers associated with myocardial fibrosis and hypertrophy, and inhibited cilia-specific protein expression as well as oxidative stress parameters. [circled4] The correlation mechanism. The cilia-specific drug hedgehog pathway inhibitor 4 (HPI-4) was used to revealed that cilia homeostasis is closely linked to myocardial fibrosis and shortened cilia inhibit the fibrosis progression. Furthermore, upregulation of the Pkd1 gene by small activating RNA demonstrated that PC1 overexpression abrogates the therapeutic effect of GRo. Finally, GRo can alleviate DiaCM.

Molecular Biology↗

A missense mutation in FBXL3 links circadian regulation to out-of-season estrus in sheep

Seasonal breeding is a remarkable adaptive trait, but it constrains efficient production in the sheep industry. Recent studies have shown that seasonal breeding is associated with endogenous circannual rhythms, which are regulated in part by the circadian clock system. FBXL3, a pivotal component of the SCF (SKP1 - CUL1 - F-box) E3 ubiquitin ligase complex, is a known determinant of the mammalian circadian period. In this study, we identified a missense mutation, T183M, in FBXL3 through selective sweep analysis. The allele frequency of this mutation differed significantly between sheep breeds exhibiting year-round estrus and those showing seasonal breeding patterns. The association between the T183M mutation and seasonal breeding was further validated using an ovariectomized, estradiol-implanted sheep model. We then generated mice carrying the homologous T183M mutation and found that they exhibited significantly lengthened circadian periods, accompanied by reduced CRY1 expression and increased CLOCK expression. Co-immunoprecipitation assays confirmed that the mutation reduced the interaction between FBXL3 and CRY1. These findings demonstrate an evolutionarily conserved role of FBXL3 in the circadian clock system. We propose that the T183M mutation disrupts day-length recognition, thereby influencing seasonal estrus in sheep. Author summarySeasonal breeding limits sheep productivity and is regulated by circadian rhythms, yet the key genetic determinants remain poorly understood. Here, we identified an FBXL3 T183M missense mutation whose allele frequency differed markedly between year-round-estrous and seasonally breeding sheep, and validated its association with seasonal reproduction in a sheep population. Functional analyses in mutant mice showed that this variant lengthened the circadian period, disrupted the expression of core clock genes, and weakened the interaction between FBXL3 and CRY1. These findings suggest that the FBXL3 T183M variant impairs day-length perception, thereby modulating seasonal estrus in sheep. Our study reveals a conserved circadian mechanism underlying seasonal breeding and highlights FBXL3 T183M as a promising genetic target for improving reproductive performance in sheep.

genetics↗

Auditory Working Memory and Sound Segregation Ability Predict Speech-in-Noise in Adult Cochlear Implant Users

ObjectivesOutcomes following cochlear implantation vary substantially across adult recipients, and the cognitive and perceptual factors contributing to this variability are not fully understood. This poses a challenge for developing strategies to improve cochlear implant outcomes, as such approaches require a clearer understanding of the mechanisms underlying individual listening difficulties. In this study, we investigated auditory cognitive measures in cochlear implant (CI) users to further elucidate the origins of this variability. DesignThirty-seven adult cochlear implant users completed measures of auditory cognition, comprising auditory working memory (AWM) and sound segregation ability, measured using an auditory figure-ground task (AFG), as well as measures of peripheral temporal and spectral processing, comprising the temporal modulation detection threshold (TMDT) and spectral ripple discrimination threshold (SRDT). Speech perception outcomes were assessed using word-in-noise (WIN) and sentence-in-noise (SIN) tasks. Separate multiple linear regression models evaluated the unique contribution of the auditory cognition measures to WIN and SIN performance, after accounting for the peripheral measures. ResultsBoth regression models explained a substantial proportion of variance in speech-in-noise outcomes (WIN: adjusted R{superscript 2} = 0.55; SIN: adjusted R{superscript 2}=0.57, both p < 0.001). For WIN performance, AFG and AWM were significant predictors. A similar pattern was found for SIN performance, where lower AWM ability and poorer AFG segregation were linked to poorer sentence listening in noise. No significant effects of spectral ripple discrimination or temporal modulation detection were observed in either model, even though both were significantly correlated with WIN performance. ConclusionsThese findings indicate that auditory working memory and sound segregation ability are robust predictors of speech-in-noise outcomes in adult cochlear implant users, across both word- and sentence-level measures. Together, the results may help explain why speech-in-noise outcomes remain highly variable among CI users, even when basic sensory encoding abilities are taken into account. Incorporating measures of auditory working memory and fundamental sound segregation may therefore improve outcome prediction and help in developing more individualised rehabilitation strategies.

neuroscience↗

Microbial Influenced Corrosion: A Novel Initiator of In Vivo Spine Rod Fracture

ABSTRACTSpine rod catastrophic failure/rod fracture after implantation is estimated to occur in [~]10% of all cases worldwide with this rate remaining consistent for more than 20 years. To accommodate the spine mechanical environment, metal alloys such as austenitic stainless steels, cobalt-chromium-molybdenum alloys, and /{beta} type titanium alloys such are used as they have a high resistance to fatigue failure. The work presented herein addresses the gap in understanding about what happens in a laboratory environment versus what is happening in human patients that results in metal leaching into tissues as well as a shortened lifespan of a spine rod in a patient population that is not capable of breaking these spine rods from purely mechanical means. Eighty-five (N=85) patients (51 female - 62.9 {+/-} 13.5 years old, 34 male - 62.7 {+/-} 10.9 years old) who had spine revision surgery due to patient mechanical issues, such as loss of sagittal or coronal balance, pain, pedicle screw loosening, hardware associated infection were included in this study. All explanted rods had optical indications of surface modification that were not the result of mechanical damage, e.g. gouges, scratches, notches. The presence of Ti6Al4V rods increases the presence of local tissue concentrations of elemental Ti (190.98 {+/-} 207.84 g/g (ppm)) in all patients over the amount that would normally be present in patients who never had any titanium based orthopedic device implants (spinous muscle, 13.12 {+/-} 11.43 g/g). PQS, HHQ, and NHQ ToF-SIMS molecular signals were found co-located to corrosion pits as well with AHLs and palmitic acids indicating microbial presence and metabolism in all patients. This suggests that MIC can cause in vivo pitting corrosion resulting on rod failure.

bioengineering↗

(2R,6R)-Hydroxynorketamine elicits rapid antidepressant effects by promoting astrocytic μ-δ opioid receptor heterodimerization

Ketamine produces rapid antidepressant effects but is constrained by psychotomimetic properties and abuse potential. The ketamine metabolite (2R,6R)-hydroxynorketamine (HNK) shows antidepressant-like efficacy without N-methyl-D-aspartate receptor (NMDAR) blockade, yet its upstream targets remain unclear. Here we show that HNK potentiates hippocampal excitatory transmission and reverses stress-induced behavioural deficits through opioid receptor signaling. Pharmacological and genetic analyses reveal a requirement for both {micro}- and {delta}-opioid receptors in astrocytes. Chronic stress reduces {micro}-{delta} receptor heterodimers in the hippocampus, and a single dose of HNK restores their abundance. PAINT-MINFLUX nanoscopy quantifies increased {micro}-{delta} heterodimerization, and molecular dynamics simulations indicate selective binding of HNK to the {micro}-receptor protomer via Asp147 and Tyr148. Mutating these residues abolishes HNK-driven heterodimer formation, downstream signaling and rapid antidepressant-like effects in vivo. Astrocytic {micro}-{delta} opioid receptor heterodimers thus represent a targetable mechanism for next-generation rapid-acting antidepressants.

neuroscience↗

Elamipretide reverses female fertility decline during reproductive aging via regulating VEGF in oocytes

Aging is one of the primary drivers for the decline of female fertility, and oocyte quality is the main cause for ovary aging, which is related with infertility. Although some effective anti-aging natural components have been reported, highly efficient strategies for reversing ovary aging remain lacking. In this study, we reported that peptide elamipretide reserved ovary function for female fertility during maternal aging. Our findings demonstrated that elamipretide improved aged human oocyte maturation and fertilization. Elamipretide injection increased the litter size of aged mice, and improved oocyte quality with the reverse of follicle and embryo development defect. Metabolomic and transcriptomic analyses demonstrated that multiple biological processes in oocytes were significantly reserved. Both nuclear maturation and cytoplasmic maturation of aged oocytes were improved, showing with enhancing cytoskeletal dynamics, mitochondrial metabolism and organelle rearrangement. In vitro supplementation during culture also restored oocyte developmental competence in both mouse and porcine oocytes. Mechanistic analysis suggested that elamipretide reversed age-related ovarian damage via synergistic activation of the Vitamin B6-VEGF axis. Therefore, our study proposed a new peptide therapy for aging-induced infertility, showing that elamipretide reverses aged oocyte quality for fertility by promoting both nuclear and cytoplasmic maturation through the coordination with VEGF signaling pathway.

developmental biology↗

BMSC-Laden PEGDA/HAMA Dual-Crosslinked Hydrogels with Distinct Stiffness Profiles for Osteochondral Defect Repair

This study aimed to develop a BMSC-laden polyethylene glycol diacrylate/methacrylated hyaluronic acid (PEGDA/HAMA) dual-crosslinked hydrogel and evaluate its effects on osteochondral defect repair. Two PEGDA concentrations, 3.75% and 7.5% (w/v), were used to prepare representative soft and stiff hydrogel formulations, respectively. The hydrogels were characterized in terms of morphology, cytocompatibility, and compressive behavior, and their ability to support BMSC-associated matrix deposition was evaluated in vitro. Repair outcomes were further assessed in a rat osteochondral defect model at 4 and 8 weeks. The 7.5% PEGDA/HAMA hydrogel exhibited higher stiffness than the 3.75% formulation and supported BMSC viability and matrix deposition in vitro. In vivo, the stiff hydrogel group showed improved defect filling and subchondral bone remodeling compared with the soft hydrogel and defect groups. However, histological and immunohistochemical analyses revealed predominant collagen type I deposition and limited collagen type II expression in the repair region, indicating fibrocartilaginous rather than hyaline-like cartilage repair. These findings suggest that BMSC-laden PEGDA/HAMA hydrogels may provide a useful platform for osteochondral defect repair, while further optimization of degradation behavior, matrix maturation, and collagen type II deposition is required to improve hyaline cartilage-oriented repair.

bioengineering↗

StructAgent: Orchestrating Cryo-EM Model Building and Refinement with a Multi-Agent LLM System

Building and refining cryo-EM atomic models often requires long, project-specific workflows that combine map inspection, prior structural knowledge, restraints, refinement, validation and expert review. Existing programs perform many individual operations, but coordinating them across iterative model-building sessions remains manual and difficult to audit. We present StructAgent, a user-guided multi-agent resource for cryo-EM model building and refinement. StructAgent couples a domain agent for literature-grounded structural reasoning with an execution agent that runs local software, tracks state, recovers from failures and records provenance. Expert approval gates control major model-changing actions. In three case studies, StructAgent refitted a 64-chain proteasome from an earlier template, audited 530 ribosomal metal-ion sites and guided a chemically ambiguous ligand fit in a folate-metabolism enzyme from ongoing work. These demonstrations show that agentic orchestration can convert modeling intent into auditable, reviewable software workflows while preserving expert control and final scientific judgment.

biochemistry↗

TDP-43 regulates chromatin looping and gene transcription through binding and stabilizing DNA G-quadruplex structures

TAR DNA-binding protein 43 (TDP-43) is a multifunctional DNA/RNA-binding protein implicated in transcriptional and post-transcriptional regulation. Dysregulation of TDP-43 is closely correlated with human diseases such as cancer and neurodegenerative diseases. Although its roles in RNA metabolism are well characterized, its function in transcriptional regulation remains largely underexplored. DNA G-quadruplexes (dG4s) are non-canonical nucleic acid structures enriched at gene promoters and regulatory elements, where they facilitate chromatin looping and gene transcription. Here, we investigated the transcriptional regulatory role of TDP-43 by integrating multi-omics datasets, including Hi-C, dG4 ChIP-seq, TDP-43 ChIP-seq, RNA-seq and ATAC-seq from K562 and HepG2 cells. Our analyses demonstrate TDP-43 binding and dG4s formation are highly colocalized at chromatin loop anchors, particularly at promoter and enhancer regions. TDP-43 occupancy at these anchors correlates with increased dG4 stability, chromatin loop interaction frequency, elevated chromatin accessibility, and upregulated gene expression. Morover, TDP-43 knockdown in HepG2 cells revealed a significant reduction in dG4 formation and loop interaction strength, accompanied by widespread transcriptional dysregulation. Collectively, our findings highlight a novel regulatory role of TDP-43 in facilitating long-range chromatin interactions and transcriptional activation through binding to and stabilizing dG4 structures, providing a mechanistic basis for gene dysregulation driven by TDP-43 dysfunction in diseases.

bioinformatics↗

Benthic diatoms navigate shear flows via hydrodynamic rolling and active gliding

Navigating fluid flow is a fundamental challenge for microbial life across diverse aquatic environments. While rheotaxis in swimming microorganisms has been extensively studied, it remains unresolved whether near-bed shear merely perturbs gliding motility or instead provides directional cues for active navigation on surfaces. Here we show that the benthic diatom Navicula cryptocephala utilises a purely mechanical strategy to achieve downstream rheotaxis and anisotropic spreading on submerged surfaces. Single-cell ellipsoidal tracking reveals a direction-dependent angular response that reorients gliding cells towards the downstream direction. Using interference reflection microscopy, we further reveal that shear induces rolling of obliquely gliding cells, laterally shifting the cell-substrate contact site. This shift renders raphe-based propulsion non-collinear with substrate friction, generating a downstream-restoring yaw torque. Crucially, our results rule out alternative explanations based on longitudinal shifts of the raphe contact site or direct hydrodynamic yaw torque. A minimal stochastic model confirms that this mechanical reorientation alone is sufficient to reproduce the observed drift and diffusion patterns, without invoking either orientation-dependent switching between motility states or orientation-dependent dwell times of those states. Our findings uncover a mechanism by which ambient shear is converted into directional guidance for active surface motility, providing new insights into microbial transport, retention, and resilience on submerged surfaces.

biophysics↗

Auditory Working Memory Mediates the Relationship between Musical Sophistication and Speech-in-noise Perception

Understanding speech in noisy environments (SPIN) is an important everyday ability, and engaging in musical activities has been proposed as a factor that may support this ability. However, the cognitive mechanisms underlying a potential musical advantage in SPIN perception remain unclear. Here we investigated whether musical sophistication is associated with better SPIN perception in a large population-based sample, and whether this relationship is mediated by auditory working memory (AWM), verbal working memory (VWM), or non-verbal intelligence. We recruited 203 participants and measured SPIN perception at both word and sentence levels. Musical sophistication was assessed using the Goldsmiths Musical Sophistication Index (Gold-MSI). AWM was measured using delayed matching of tone frequency or the modulation rate of amplitude modulated white noise, VWM was based on backward digit span task, and non-verbal intelligence used matrix reasoning. Mediation analyses revealed that AWM fully mediated the relationship between musical sophistication and SPIN perception, whereas VWM showed no mediation effect. Non-verbal intelligence showed a partial mediating effect. Additional control analyses using structural equation modelling revealed that the indirect effect through AWM remained significant after accounting for age, hearing thresholds, and non-verbal intelligence. Together, these findings suggest that individuals with greater musical sophistication demonstrate better daily life listening abilities, and that superior auditory working memory may be the key cognitive mechanism underlying this advantage.

neuroscience↗

OmniAge: a compendium of aging omic biomarkers links mitotic clocks to clonal hematopoiesis and causality

Interest in aging omic biomarkers has grown due to their ability to quantify biological age. Most of these biomarkers have been derived in blood and fall into many diverse categories, yet relatively little is known about their correlative patterns, especially between biomarkers from different categories. Here we present the OmniAge R and Python package, a collection of 413 aging omic biomarkers representing 12 different categories, including traditional epigenetic clocks, epigenetic mitotic clocks, DNA methylation-based proxies for clonal hematopoiesis and inflammaging, causal clocks, cell-type specific epigenetic clocks and single-cell transcriptomic clocks. By studying their inter-class correlations across large blood datasets, we reveal associations of mitotic age with clonal hematopoiesis subtypes and causal clocks, which are predictive of cancer risk. Using proxies of serum protein levels, we further dissect associations with mitotic clocks, clonal hematopoiesis and causal clocks into distinct biological processes mapping to key aging pathways. Applying OmniAge to multi-modal data of sorted immune cell-types reveals that age-acceleration derived from transcriptomic and epigenetic clocks correlate, but that this is driven by underlying cell-type heterogeneity. In summary, the OmniAge package is an exploratory tool for evaluating large numbers of aging omic biomarkers, and to aid discovery and generate new hypotheses.

bioinformatics↗

N-3 Polyunsaturated Fatty Acids Ameliorate Post-infarction Cardiac Dysfunction Through Modulation Of Adiponectin-Ceramide Metabolism

BackgroundIt has been shown that n-3 polyunsaturated fatty acids (n-3 PUFA) of marine origin exert significant beneficial effects on myocardial infarction (MI); however, the underlying mechanisms remained unclear. Ceramides play a vital role in the regulation of energy metabolism, mitochondrial function, and apoptosis. Through the integration of clincial studies and animal experiments, this study aimed to determine whether n-3 PUFA improved myocardial function by modulating ceramide metabolism. MethodsIn a case-control study, 100 patients with AMI and 100 healthy pariticipants were enrolled to measure serum ceramide concentrations. Meanwhile, mice were randomly allocated into 4 groups and administrated to a 3-week intervention with n-3 PUFA in triglyceride and phospholipid forms. A mouse model of MI was then established, followed by an additional 4 weeks of continuous intervention. Subsequent comprehensive assessments of cardiac function were performed in the mice. Finally, the mice were euthanized to conduct targeted ceramide lipidomic analysis and other relevant assays. ResultsThe levels of serum C16:0-, C18:0-, C20:0-, C24:1-ceramides and total ceramides in patients with acute myocardial infarction (AMI) were significantly higher compared with the healthy controls. In the murine model of myocardial infarction, pathological analysis via TTC staining demonstrated that interventions with fish oil (triglyceride form) and krill oil (phospholipid form) both significantly reduced myocardial infarct size. Concomitant echocardiographic assessment confirmed that both treatments markedly elevated left ventricular ejection fraction (LVEF), with the magnitude of improvement being significantly superior to that of the model control group. Concurrently, compared with the model group, the concentrations of ceramides in cardiac tissue and serum were significantly lower in the groups with fish oil and krill oil intervention. Western blot analysis further confirmed that n-3 PUFA intervention upregulated adiponectin expression, reduced ceramide accumulation in myocardial tissue, and inhibited mitochondria-mediated cardiomyocyte apoptosis, thereby improving cardiac function and prognosis following myocardial infarction. ConclusionsThis work demonstrates that n-3 PUFA exert cardioprotective effects following MI mediated by adiponectin-ceramide axis. However, there is no significant difference regarding therapeutic efficacy of n-3 PUFA in triglyceride or phospholipid forms.

pharmacology and toxicology↗