Search PubMedSearch

SEARCH · Search PubMed

Results for “Gene clusters”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

540 records · Page 22Linked to original sources

Epitranscriptomic erasers in bivalves: Evolutionary divergence and species-specific transcriptional plasticity of the ALKBH family under acute thermal stress.

The AlkB homolog (ALKBH) family of Fe(II)/α-ketoglutarate-dependent dioxygenases mediates nucleic acid demethylation, thereby governing RNA metabolism and genomic stability. Despite their pivotal roles in epitranscriptomic regulation across vertebrates, the evolutionary dynamics and functional significance of ALKBH proteins in bivalve mollusks remain largely unexplored. Here, we present a comprehensive phylogenomic analysis of 210 ALKBH genes identified across 35 bivalve species. Our analyses reveal a distinct evolutionary trajectory characterized by the lineage-specific loss of ALKBH4 and the restricted distribution of ALKBH5 to the Mytilidae family, contrasting sharply with vertebrate repertoires. Using the noble scallop (Chlamys nobilis) and Pacific oyster (Crassostrea gigas) as model systems, we demonstrate that ALKBH genes exhibit conserved spatiotemporal expression patterns, with pronounced enrichment in gonadal tissues and during metamorphic transitions, implicating these enzymes in gametogenesis and larval development. Furthermore, comparative thermal stress experiments reveal divergent transcriptional plasticity: the subtropical scallop C. nobilis mounts rapid, transient induction of ALKBH1/2/6 under heat shock, whereas the eurythermal oyster C. gigas maintains sustained ALKBH3 expression, potentially underpinning its superior thermal tolerance. Conversely, cold stress elicits bimodal regulation in C. nobilis, with ALKBH1/2 upregulation contrasting with ALKBH6/7/8 suppression. These findings illuminate the functional diversification of bivalve ALKBH genes and their potential utility as molecular biomarkers for assessing developmental competence and thermal resilience in shellfish aquaculture.

Animals

Characterization and functional insights of histone deacetylases in bivalves: implications for temperature and immune response in Chlamys nobilis.

Histone deacetylases serve as pivotal epigenetic regulators that modulate chromatin remodeling and gene transcription, playing critical roles in immune defense and environmental stress responses in aquatic organisms. However, the evolutionary characteristics and functional roles of the HDAC family in bivalves remain poorly understood. In this study, genome-wide identification of the HDAC family across 30 bivalve species yielded 558 HDAC genes. Phylogenetic reconstruction categorized these genes into four conserved groups and revealed a unique, bivalve-specific SIRT8 clade. Using the noble scallop Chlamys nobilis as a representative model, expression profiling revealed distinct expression patterns among CnHDAC members. Class I and most Class III members were predominantly expressed in the gonads, while Class II members were enriched in immune-related tissues, implying their potential involvement in bivalve immunity. Upon temperature stress, CnHDAC1/2, CnHDAC11-1, CnHDAC11-2, CnSIRT2-1, CnSIRT4, CnSIRT6, and CnSIRT8-3 were significantly induced, highlighting their critical roles in temperature adaptation. Upon Vibrio exposure, CnHDAC1/2, CnHDAC8, CnSIRT4, and CnSIRT6 were upregulated, while CnHDAC4/5/7/9, CnHDAC6/10, CnSIRT2-2, CnSIRT5, CnSIRT7, and CnSIRT8-3 were downregulated, suggesting a coordinated epigenetic regulatory mechanism underlying host immune defense. In conclusion, this study systematically elucidates the evolutionary landscape of the HDAC family and underscores its potential involvement in environmental resilience and host immunity, providing a theoretical basis for the breeding of disease-resistant and stress-tolerant aquaculture bivalves.

Animals

Male accessory gland proteins in Grapholita molesta: Identification and reproductive functional validation of four accessory gland-specific lipases.

Accessory gland proteins (Acps), synthesized in the male accessory glands (AGs), are transferred to females via spermatophores during mating and elicit diverse post-mating physiological and behavioral responses. However, Acps have not been comprehensively characterized in Grapholita molesta, a cosmopolitan orchard pest. Here, using data-independent acquisition mass spectrometry, we describe an integrated proteomic approach combining comparative AG analyses (virgin vs. newly mated) with spermatophore profiling to identify Acps in G. molesta. According to the established screening criteria, we identified 83 confirmed Acps, which were classified into nine categories. Tissue-specific expression patterns of 20 randomly selected Acp genes were evaluated, revealing that these genes were specifically or highly expressed in male AGs. Among the 83 confirmed Acps, four Acps harbored the PLN02872 superfamily domain and were classified into the canonical lipase family. Notably, their transcripts were all highly expressed in the AGs during the pre-maturation stage. These four Acps were selected for preliminary validation of their male reproductive functions. RNAi-mediated knockdown of three out of four lipase genes in G. molesta males significantly decreased the fertility of mated females, with phenotypes including a significant reduction in egg production and egg hatching rate. This study provides a comprehensive catalog of high-confidence Acps, lays a foundation for subsequent in-depth functional characterization of these reproductive proteins, and offers promising molecular targets for the development of novel genetic regulation-based integrated pest management strategies.

Animals

A multi-model genome-wide association study identifies genetic variants underlying resistance to Largemouth Bass Ranavirus (LMBV) in Micropterus salmoides.

Largemouth bass (Micropterus salmoides) is an economically important freshwater aquaculture species, yet recurrent outbreaks of Largemouth Bass Ranavirus (LMBV) continue to impair production and cause substantial losses. The genetic basis of host variation in LMBV resistance remains insufficiently characterized. Here, we applied a multi-model genome-wide association study (GWAS) to identify loci associated with resistance following a controlled challenge with the LMBV-23PY strain. Whole-genome resequencing was performed for 146 phenotyped fish, including 72 susceptible and 74 resistant individuals. After stringent quality control, 877,262 high-quality variants were retained and tested using six GWAS models. Across binary survival status and survival time phenotypes, 32 shared suggestive variants were consistently detected across models, representing suggestive loci for LMBV-23PY resistance. Genes within ±50 kb of these loci were annotated, and functional enrichment highlighted immune- and redox-related biological processes. Three prioritized candidates-GSTT3L (glutathione S-transferase theta-3-like), CGRP2 (calcitonin gene-related peptide 2), and NPPC (natriuretic peptide C)-were associated with pathways involved in oxidative stress responses and immune regulation. Collectively, these results provide insight into the genetic architecture of LMBV-23PY resistance in largemouth bass and identify suggestive variants and associated candidate genes for downstream validation, functional interrogation, and the development of marker-assisted and genome-enabled breeding strategies.

Animals

Dynamic evolution of chaperone-mediated autophagy is associated with tumor microenvironment remodeling and prognostic stratification in lung adenocarcinoma: insights from single-cell transcriptomics, ensemble machine learning, and experimental validation.

BACKGROUND: Lung adenocarcinoma (LUAD) shows prognostic heterogeneity, and tumor-node-metastasis (TNM) staging is limited for individualized management. Chaperone-mediated autophagy (CMA) maintains proteostasis, but its role during adenocarcinoma in situ (AIS)-minimally invasive adenocarcinoma (MIA)-invasive adenocarcinoma (IAC) progression remains unclear. METHODS: Single-cell RNA sequencing (scRNA-seq) data from GSE189357 and bulk transcriptomes from The Cancer Genome Atlas (TCGA)-LUAD and Gene Expression Omnibus (GEO) cohorts were integrated. CMA activity, cell-cell communication, weighted gene co-expression network analysis (WGCNA), tumor-normal differential expression, machine-learning survival modeling, tumor microenvironment (TME) features, drug sensitivity, and EPC1 function were analyzed. RESULTS: CMA-high tumor epithelial cells increased from AIS (58.1%) to MIA (65.7%) but declined in IAC (44.4%; p < 0.001). CMA-low cells preferentially received fibroblast-derived extracellular matrix cues. A CMA-negatively correlated module identified 69 core genes. Random survival forest (RSF) performed best among 117 machine-learning combinations (mean concordance index > 0.873). High-risk patients had worse survival across cohorts, and the risk score was independently associated with overall survival (hazard ratio = 16.013, 95% confidence interval: 9.579-26.768, p < 0.001). High-risk tumors showed proliferative activation and M0 macrophage enrichment, whereas low-risk tumors showed stronger immune-related signaling. EPC1 overexpression suppressed malignant phenotypes in A549 cells. CONCLUSION: CMA dynamics are associated with stromal and immune remodeling during LUAD progression. A CMA-based model provides robust prognostic stratification and may offer a basis for future TME-guided studies.

Chaperone-mediated autophagy

Evidence of genome-wide relaxed selection on mildly deleterious mutations in an ancient subterranean catfish.

About one hundred subterranean catfish species have been described, resulting from repeated colonization of cave environments by multiple surface lineages. Most cave-dwelling species are found in the Americas, in particular in South America, but a few species also live in Central and North America. Despite the availability of high-quality genome assemblies for two cave species, the Mexican blind catfish Prietella phreatophila and the Colombian blind catfish Trichomycterus rosablanca, genomic approaches to investigate genetic changes associated with subterranean life or to estimate cave colonization times remain largely unexplored. To fill this gap, we additionally sequenced the genomes of four blind and depigmented subterranean catfishes from Peru (three Trichomycterus and one Astroblepus), as well as the genomes of four close surface relatives. We first extracted a large set of light-related genes, such as phototransduction and crystallin genes, and found contrasting decays of these sequences in different cave species, from 1% of pseudogenes in T. rosablanca to 48% in P. phreatophila. Two independent molecular dating methods gave congruent ages, indicating that these catfishes colonized subterranean habitats at different times, ranging from Early Pliocene to Late Pleistocene, supporting the hypothesis that surface catfishes repeatedly and rapidly adapted to subterranean habitats. The oldest cave species, P. phreatophila, appears to have been thriving in the dark for over 3.5 million years. Moreover, a genome-wide analysis of protein-coding genes suggests weaker purifying selection on mildly deleterious mutations in this cavefish than in other catfish lineages, likely reflecting a long-term small effective population size.

cavefishes

Cost-Effectiveness and the Economics of Genomic Testing and Molecularly Matched Therapies.

Cost-effectiveness analysis of precision oncology can help guide value-driven care. Next-generation sequencing is increasingly cost-efficient over single gene testing because diagnostic algorithms require multiple individual gene tests to determine biomarker status. Matched targeted therapy is often not cost-effective due to the high cost associated with drug treatment. However, genomic profiling can promote cost-effective care by identifying patients who are unlikely to benefit from therapy. Additional applications of genomic profiling such as universal testing for hereditary cancer syndromes and germline testing in patients with cancer may represent cost-effective approaches compared with traditional history-based diagnostic methods.

Humans

Comparative profiling of microbial community structure, enzyme potential, metabolic features, and volatile composition in craft and Jiafan Huangjiu processes.

Craft Huangjiu and Jiafan Huangjiu represent two distinct industrial Huangjiu product outcomes with contrasting volatile profiles. This study compared craft Huangjiu (L70) and Jiafan Huangjiu (L79) to characterize their physicochemical, microbial, gene-level functional, metabolic, and volatile features. Because L70 involved mid-fermentation addition of finished Huangjiu, this comparison was not intended to isolate the sole effect of fermentation interruption versus continued fermentation. L79 showed more extensive carbon and nitrogen utilization, with lower residual substrates and higher ethanol and acetic acid contents than L70, whereas L70 retained a less complete fermentation state. At the volatile level, GC-MS and volatile metabolomics consistently showed an ester-enriched profile in L79 and a more alcohol-dominant profile in L70. FlavorDB-based putative annotation and threshold-based OAV analysis further indicated distinct database-assigned descriptor distributions and potential odor-active compounds, with more OAV&#xa0;>&#xa0;1 ester-related compounds in L79. Metagenomic analysis showed that L70 was dominated by Lactobacillus acetotolerans, whereas L79 contained higher relative abundances of Saccharomyces cerevisiae, Aspergillus oryzae, Aspergillus flavus, and Fructilactobacillus fructivorans. Metagenomic functional annotation showed higher representation of hydrolysis-related CAZy genes and ester-related enzyme annotations in L79. KEGG-based pathway mapping further indicated greater gene-level potential for ethanol-, acetate-, and acetyl-CoA-related metabolism in L79. Accordingly, the L70 profile should be interpreted as the integrated final-product outcome of process intervention, exogenous input, and subsequent fermentation. The findings provide a comparative basis for future flavor regulation and process optimization in Huangjiu and other fermented alcoholic beverages.

Volatile Organic Compounds

Characterisation of HIV-1 Gag Cytotoxic T-Lymphocyte Epitopes in the Southern African Region-A Systematic Review.

During early HIV-1 infection, robust Cytotoxic T-lymphocyte (CTL) responses are mostly targeted at immunodominant Gag p24 epitopes to reduce HIV-1 viraemia to a set-point. The aim of this study was to review the current body of knowledge on HIV-1 Gag CTL epitopes in the southern African region where subtype C is prevalent. Peer-reviewed records were obtained from three databases: PubMed Central, Web of Science Core Collection, and Scopus, using the following search terms: HIV subtype C Gag epitopes, and HIV clade C Gag epitopes. The search results were restricted to countries within the southern African region, and only data published in English and between the years 2000-2025 were considered for this review. The search from the three databases produced a total of 2103 peer-reviewed records, and 49 records were included in the review. The majority of studies (58.44%) were conducted in South Africa, followed by Botswana (15.58%), Zambia (10.39%), Malawi (7.79%), Zimbabwe (6.49%) and Angola (1.30%). There were no studies identified from other southern African countries. A total of 60 Gag CTL epitopes were identified, of which 17 (28.33%) were located within the matrix protein (p17), 33 (55.00%) within the capsid protein (p24), and 4 (6.67%) within the Gag polyprotein (p2p7p1p6). The commonly detected immunodominant epitopes were mostly located within the Gag p24 protein; and included TPQDLNTML (TL9, Gag p24 48-56) and TSTLQEQIGW (TW10, Gag p24 108-117) present at 16.00% and 13.3%, respectively. The proportion of HLA-A, B and C allotypes in this systematic review were 18%, 78%, and 4%, respectively. The more common HLA-B allotypes that restrict immunodominant Gag epitopes and facilitate better control of HIV-1 were HLA-B*57, -B*58:01, -B*42:01 and -B*81:01. This systematic review has provided important insights into the description of immunodominant Gag epitopes and HLA-I alleles that contribute to the control of HIV-1 viraemia in the southern African region. It has also exposed that some CTL epitopes identified in the southern African studies are not reported on the Los Alamos HIV database (LANL HIV database). This highlights a need to have this database updated with this information as it is used as a reference for epitopes. This review could provide insights into the design of an epitope-based HIV-1 vaccine that would also be effective in the southern African region.

Humans

Effects of umbilical cord mesenchymal stem cell-derived exosomes on periodontal ligament stem cells: An exploratory study.

OBJECTIVE: To investigate whether exosomes derived from human umbilical cord mesenchymal stem cells (UCMSCs) at two osteogenic induction stages (undifferentiated and late-stage) differentially affect periodontal ligament stem cells (PDLSCs), and to explore the potential molecular basis. DESIGN: UCMSCs and PDLSCs were isolated and cultured. Exosomes were harvested from undifferentiated UCMSCs (Exo-D0) and UCMSCs after 14 days of osteogenic induction (Exo-D14). PDLSCs were treated with both exosome types. Proliferation and migration were analyzed using EdU and scratch assays, the latter under serum-free conditions. Early osteogenic differentiation was assessed by alkaline phosphatase staining and quantitative reverse transcription PCR (qRT-PCR). Differentially expressed miRNAs were identified by high-throughput sequencing and further analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. RESULTS: Both exosome types promoted PDLSC migration. Exo-D0 enhanced early osteogenic differentiation, whereas Exo-D14 enhanced proliferation but reduced early osteogenic marker expression. Sequencing identified 21 differentially expressed miRNAs (13 upregulated, 8 downregulated). Bioinformatic prediction suggested that the putative target genes were enriched in Ras signal transduction, regulation of kinase activity, and focal adhesion, and further predicted significant enrichment in the MAPK, Ras, and PI3K-Akt signaling pathways, which are central to cell proliferation and osteogenic differentiation. CONCLUSIONS: Exosomes from undifferentiated and osteogenically induced UCMSCs exerted distinct effects on PDLSCs, potentially associated with differentially packaged miRNAs. These findings offer a basis for hypotheses about exosome-mediated mechanisms and support matching exosome sources to the intended therapeutic outcome as potential cell-free strategies for periodontal tissue regeneration and alveolar bone repair.

Humans

Genetic evidence for a causal relationship between melatonin metabolism and depression.

To investigate the causal relevance of melatonin metabolism, which provides the biological basis for circulating melatonin levels, to specific depression symptom subtypes, we performed a targeted systematic review of melatonin metabolism pathways in the human brain and liver. Using two-sample Mendelian randomization (MR), we assessed the causal effects of metabolism pathways and/or individual genes on major depressive disorder (MDD) and nine symptom subtypes derived from Patient Health Questionnaire-9 (PHQ-9). Instrumental variables (IVs) were expression quantitative trait loci (eQTL) for eight individual genes, one synthesis route, and three degradation routes. Results were assessed using Bayesian colocalization and phenome-wide association analyses. At the pathway-level, the genetically proxied synthesis-route signal was associated with PHQ-9 Assessment 5 (PHQ9A5, OR: 0.89, 95% CI: 0.85-0.93), but sensitivity analyses suggested this association was primarily driven by TPH1 and may reflect serotonin-related biology. In contrast, higher brain melatonin degradation raised the risk of both PHQ9A1 (OR: 1.03, 95% CI: 1.02-1.04) and PHQ9A7 (OR: 1.03, 95% CI: 1.02-1.03). Within degradation, up-regulation of the kynurenine sub-pathway increased the odds of PHQ9A3 (OR: 1.05, 95% CI: 1.02-1.07), PHQ9A4 (OR&#xa0;=&#xa0;1.04, 95% CI: 1.02-1.06) and PHQ9A7 (OR: 1.05, 95% CI: 1.02-1.07). Gene-level analyses were largely concordant, except for SULT1A1, whose higher expression was genetically protective for PHQ9A3 but risk-increased for PHQ9A1 and PHQ9A4. Overall, these results demonstrate that melatonin metabolism exerts symptom-specific and pathway-specific causal effects on depression. A stratified view of melatonin's role may help optimize the application of exogenous melatonin supplementation.

Melatonin

Hope is linked with more favorable tumor molecular signatures in serous ovarian cancer.

INTRODUCTION: Hope has been associated with improved quality of life and lower mortality in cancer, but the underlying biological mechanisms are poorly characterized. We previously reported that hope was associated with less inflammation and more normalized diurnal cortisol pre-treatment among women with ovarian cancer. We also reported associations of socio-environmental factors with pro-metastatic processes. Here, we used genome-wide transcriptional profiling to quantify associations between hope and tumor molecular signatures reflecting invasiveness, inflammation, and cellular immunity. METHOD: Participants were 74 women with serous ovarian cancer who provided demographic information and completed surveys pre-surgery. Hope was assessed using a face-valid item from the Center for Epidemiological Studies Depression Scale (CES-D). Depression was assessed using the full CES-D without the hope item. Illumina HT12 microarrays were used to assay tumor RNA, and associations between hope and tumor gene expression were quantified, adjusting for depression, age, BMI, grade, and stage. RESULTS: Adjusting for covariates, hope was associated with multiple favorable differences in RNA expression, including lower levels of mesenchymal differentiation (p&#x202f;=&#x202f;0.008) and pro-inflammatory gene regulation (NF-&#x3ba;B: p&#x202f;<&#x202f;0.001; IRF1: p&#x202f;=&#x202f;0.024; STAT: p&#x202f;=&#x202f;0.018), elevated epithelial differentiation (p&#x202f;=&#x202f;0.011), and elevated activity of the IRF7 transcription factor which promotes cellular immunity (p&#x202f;=&#x202f;0.016). CONCLUSIONS: These data suggest that hope is associated with an ovarian tumor gene expression profile characterized by reduced epithelial-mesenchymal transition (EMT) and inflammatory activity, and increased activity of a transcription factor promoting cellular immunity. These findings highlight potential biological implications of a resilience factor such as hope, but need replication with more robust assessments of hope.

Epithelial mesenchymal transition

Multi-Omics Genome-Wide to Explore the Formation and Development Targets for Intracranial Aneurysms.

Intracranial aneurysms (IAs) represent a significant and potentially life-threatening category of disease, and there is currently a lack of effective treatment options aimed at preventing the progression of the disease. Accordingly, this study is dedicated to exploring and identifying effective drug targets that can help in the prevention of both the formation and rupture of IAs, along with a detailed examination of the underlying potential mechanisms involved in these processes. The data related to IAs for this research was obtained from the ISGC Biobank and UK Biobank. Then, we investigated the possible biological functions and unintended consequences of targeting the specific genes that were highlighted in IAs by using mediation analysis, virtual knockout experiments, and PW-MR studies. A total of 5 unique potential drug targets for IAs (FKTN, MAP3K1, PSMA4, SLC22A4, ADAM17), 4 unique potential drug targets for SAH (PSMA4, ADAM17, GPR160, SLC22A4), and 2 unique potential drug targets for UIA (SLC22A4, PRCP) were identified across brain or blood samples. Among the various candidates identified, SLC22A4 has emerged as a promising potential drug target, showing significant expression levels in both blood and brain tissues. Additionally, phenome-wide MR of SLC22A4 across 32 selected phenotypes did not identify statistically significant adverse associations after FDR correction. Virtual knockout (KO) experiments on SLC22A4 revealed that SLC22A4 KO disrupted 81 genes, all of which are involved in IAs-related pathways. Besides, we recognized BRD-K85337334 as potential candidates for targeting SLC22A4. This research indicates that an increase in SLC22A4 gene expression within the blood or brain is directly linked to a heightened risk of IAs rupture, which will aid in prioritizing the development of drugs for IAs.

Humans

A therapeutic atlas of monogenic inflammatory bowel disease.

BACKGROUND AND AIMS: Evidence-based, mechanism-guided therapies are urgently needed for treating monogenic inflammatory bowel disease (mIBD). For such rare diseases, mechanistic insight is essential to guide treatment when conventional clinical trials are often not feasible. We aimed to summarize literature-based evidence and to identify knowledge gaps. METHODS: We conducted a systematic review of published manuscripts evaluating the therapeutic efficacy in mIBD. We quantified and compared the global therapeutic response score across treatments and conditions. In a subset of conditions, biomarkers of longitudinal therapeutic response were evaluated in comparison to non-monogenic pediatric IBD cohorts. RESULTS: Responses to 35 therapeutics across the 102 known genetic causes of mIBD were evaluated in 241 articles and 669 patients, summarizing 302 gene-drug responses. The efficacy of at least one pharmacological intervention was identified in 61% (n&#x2009;=&#x2009;62/102) of the mIBD conditions, highlighting a major unmet need for effective medications in many others. Gene- and pathway-specific responses were demonstrated for several therapies, including allogeneic hematopoietic stem cell transplantation, gene therapy, and advanced therapies such as anti-TNF agents, IL-1 inhibitors, mTOR inhibitors, as well as eculizumab in CD55 deficiency, abatacept in CTLA4 deficiency, and the immunometabolic agent empagliflozin in glycogen storage disease type 1b. CONCLUSIONS: This study highlights the potential of precision medicine approaches tailored to genetic and pathway-specific mechanisms, while underscoring the urgent need for effective therapies in many monogenic conditions that remain without established treatment options.

Humans

Exercise-associated epigenetic remodeling and TCR repertoire dynamics in Lynch syndrome carriers.

Lynch syndrome (LS) carriers are at elevated cancer risk. Emerging evidence suggests that exercise may serve as a non-pharmacologic preventive strategy, yet the epigenetic and immunological mechanisms underlying its protective effects in this population remain unclear. Here, we perform integrative multi-omics profiling of DNA methylation, gene expression, and the T cell receptor (TCR) repertoire in LS carriers undergoing a 52-week aerobic cycling intervention. We identify compartment-specific DNA methylation changes, including innate immune activation in cfDNA and oncogenic pathway repression in tissue. Integrative transcriptomic analysis highlights ISL1 as a key exercise-repressed, epigenetically regulated gene, and identifies FLCN as a colorectal cancer (CRC)-associated methylation target. TCR analysis reveals an exercise-associated increase in systemic repertoire diversity and tissue-specific clonal convergence, thus suggesting antigen-driven recruitment. Collectively, these findings uncover epigenetic and immune remodeling as potential mechanisms of exercise-mediated protection in LS.

Lynch syndrome

Pre-transport dietary chitosan improves the physiological robustness of juvenile largemouth bass (Micropterus salmoides) by modulating antioxidant and inflammatory responses.

The acute stress caused by long-distance transport can lead to oxidative damage, immune dysfunction, and health deterioration in fish. This study evaluated dietary chitosan as a pre-transport nutritional strategy for juvenile largemouth bass (Micropterus salmoides). Five experimental diets contained chitosan at 0, 2.5, 5.0, 7.5, or 10.0&#x202f;g/kg, designated as p0, p25, p50, p75, and p100, respectively, for 56&#x202f;d. The effects of dietary chitosan were evaluated using growth performance, feed utilization, digestive function, antioxidant capacity, nonspecific immunity, and resistance to Aeromonas hydrophila infection. Then, fish from the p0 and p50 groups underwent a 12-h transport stress test, with samples collected before, during, and 7&#x202f;d after transport. Dietary chitosan improved most of these parameters. Among the treatment groups, p50 and p75 showed the best overall performance. The dose-response analysis further indicated that the appropriate dietary inclusion range was 5.0-7.5&#x202f;g/kg. Under transport stress, fish in the p50 group exhibited more stable antioxidant enzyme responses and lower lipid peroxidation, as indicated by reduced MDA levels. Consistent with these enzyme responses, antioxidant-related genes remained relatively stable. At the same time, expression patterns related to the Nrf2-Keap1 and NF-&#x3ba;B signaling pathways suggested that 5.0&#x202f;g/kg chitosan alleviated transport-induced oxidative damage and inflammation. Dietary chitosan also attenuated pro-inflammatory gene induction and altered the temporal expression patterns of anti-inflammatory genes. Overall, 5.0-7.5&#x202f;g/kg dietary chitosan is suitable for juvenile largemouth bass, and 5.0&#x202f;g/kg may serve as an effective pre-transport dietary inclusion level.

Animals

Genomic epidemiology of extended-spectrum beta-lactamase-producing Escherichia coli across humans, poultry and wastewater sectors in Douala, Cameroon.

BACKGROUND: The global health threat of antimicrobial resistance involves the human, animal and environmental sectors. Data from Cameroon are scarce. OBJECTIVES: This study aimed to define extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) rates and associated risk factors across the three sectors in Douala, Cameroon, and to define molecular characteristics of isolates. METHODS: From June 2022 to May 2023, we collected blood cultures from hospitalized patients, rectal swabs from healthy pregnant women, caeca from broiler chickens and environmental wastewater. Samples were screened for ESBL-Ec using CHROMAgar&#x2122; ESBL and cefotaxime-supplemented Tryptone Bile X-glucuronide agar. Antimicrobial susceptibility testing was performed by disk diffusion following EUCAST guidelines. Whole-genome sequencing was carried out using Illumina technology. RESULTS: Of 628 samples, 374 yielded ESBL-Ec. Prevalence was 54.6% (131/240) in pregnant women, 70.4% (169/240) in chickens and 93.1% (67/72) in wastewater. The proportion of ESBL-Ec among E. coli-positive-blood cultures was 9.2% (7/76). Multi-family household living was independently associated with ESBL-Ec carriage among pregnant women (adjusted odds ratio&#x200a;=&#x200a;1.7, 95% CI 1.0-3.1, P&#x200a;=&#x200a;0.03). High co-resistance (>70%) was observed for tetracycline, ciprofloxacin and trimethoprim/sulfamethoxazole. Sequencing of 32 isolates revealed 45 distinct resistance genes, including blaCTX-M-15 (n&#x200a;=&#x200a;13, 40.6%), blaCTX-M-55 (n&#x200a;=&#x200a;11, 34.4%) and last-resort antibiotic resistance genes mcr-1 and bla OXA-181. High-risk sequence types included ST131 (pregnant women) and ST10 (chickens). Notably, ST48 was shared between pregnant women and chickens, and ST155 between pregnant women and wastewater. CONCLUSION: Cross-sectoral ESBL-Ec in Douala exhibits high genomic diversity and alarming resistance. The occurrence of last-resort genes requires immediate One Health surveillance and coordinated interventions.

Journal Article

Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals