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Efficacy of CagriSema for Reaching Anthropometric Treatment Targets and Cardiometabolic Outcomes: A Secondary, Post hoc Analysis of REDEFINE 1.

AIMS: To assess the added value of absolute anthropometric targets alongside percentage weight loss in the clinical management of obesity. MATERIALS AND METHODS: The phase 3a, 68-week REDEFINE 1 trial randomised adults without diabetes with BMI &#x2265;&#x2009;30&#x2009;kg/m2, or&#x2009;&#x2265;&#x2009;27&#x2009;kg/m2 with &#x2265;&#x2009;1 obesity-related complication, to once-weekly CagriSema 2.4&#x2009;mg/2.4&#x2009;mg, semaglutide 2.4&#x2009;mg, cagrilintide 2.4&#x2009;mg, or placebo, plus lifestyle intervention. This secondary, post hoc analysis assessed the proportions of participants achieving BMI <&#x2009;27&#x2009;kg/m2 and/or WHtR <&#x2009;0.53 targets, and percentage weight loss by anthropometric target. The association between the proportion of participants maintaining or achieving normalisation of four cardiometabolic outcomes: normoglycemia (glycated haemoglobin <&#x2009;5.7% and fasting plasma glucose <&#x2009;5.6&#x2009;mmol/L); blood pressure (<&#x2009;130/80&#x2009;mmHg); triglycerides (<&#x2009;1.7&#x2009;mmol/L); lipids (high-density lipoprotein cholesterol &#x2265;&#x2009;1.3&#x2009;mmol/L [female] or &#x2265;&#x2009;1.0&#x2009;mmol/L [male]) and reaching anthropometric targets or change in body weight (%) was also assessed. RESULTS: The proportion of participants achieving both BMI <&#x2009;27&#x2009;kg/m2 and WHtR <&#x2009;0.53 targets at week 68 was 30.3%, 19.1%, 9.0%, and 3.3% in participants who received CagriSema, semaglutide, cagrilintide, or placebo respectively. Both BMI and WHtR performed similarly as indicators for all four cardiometabolic outcomes. At more stringent cut-off values, anthropometric targets were better measures than percentage weight loss. CONCLUSIONS: The proportion of participants achieving anthropometric targets was greater with CagriSema Versus other treatments. These findings support further validation of BMI and WHtR anthropometric treatment targets and indicate a potential for indicating amelioration of clinical outcomes in obesity and a greater emphasis on target-based treatment strategies.

Humans

Inhibitory mechanism of phloretin on the AgrA LytTR domain-agr operon complex formation and its application in beef.

Staphylococcus aureus (S. aureus) represents a major foodborne pathogen whose enterotoxin production poses significant challenges to food safety due to its high environmental resistance and limited efficacy of conventional sterilization. Since the expression of enterotoxins is predominantly governed by the agr quorum sensing system, targeting this regulatory pathway has become a strategic choice for virulence control. This study elucidated the mechanism by which phloretin, a potential quorum sensing inhibitor, interferes with the agr system to attenuate virulence. To achieve this, the recombinant AgrA LytTR domain was expressed and purified, and its interaction with phloretin was characterized using thermal shift assays (TSA), electrophoretic mobility shift assays (EMSA), and molecular dynamics (MD) simulations. The results showed that phloretin specifically binds to the AgrA LytTR domain, enhancing its thermal stability and disrupting AgrA LytTR-agr operon binding by reducing the free energy of interaction between them, without causing significant structural rearrangement. Mechanistic analysis indicated that phloretin sterically hinders key &#x3b2;-sheet turn residues (HIS169, ASN201, ARG233), thereby impairing DNA recognition, downregulating RNAIII transcription, and inhibiting agr signaling. In cooked beef, phloretin significantly inhibited the secretion of enterotoxins and &#x3b1;-hemolysin, while delaying lipid oxidation and protein degradation, and maintaining the meat texture. These findings suggested that phloretin is a multifunctional substance with anti-virulence, antioxidant, and preservative properties, demonstrating its potential as a natural food preservative.

Phloretin

Assessment of the safety and efficacy of sodium pentaborate pentahydrate in individuals with overweight and obesity: a randomized, double-blind, placebo-controlled, phase 1/2 dose-finding trial.

The present study aimed to examine the short-term safety and tolerability of sodium pentaborate pentahydrate (NaB) and to explore preliminary efficacy and dose selection as secondary objectives in individuals with overweight or obesity. In this randomized, double-blind, placebo-controlled, phase 1/2 trial, conducted from July 2024 to January 2025, 177 adults with overweight or obesity were randomized, of whom 116 completed the 12-week trial. Participants received placebo or NaB at doses of 200, 400, 600, 800, or 1,000&#x2009;mg for 12&#x2009;weeks, alongside a standardized diet and exercise programme. The primary safety objective was to investigate short-term safety and tolerability through adverse events, hypoglycaemic episodes, gastrointestinal adverse events, and changes in haematological and biochemical parameters. The primary exploratory efficacy outcome was percentage change in body weight from baseline to week 12. Secondary and exploratory efficacy outcomes included body weight, body mass index (BMI), waist and hip circumferences, waist-to-hip ratio, glycaemic markers, lipid parameters, and blood pressure. Baseline characteristics were broadly similar across groups (all p&#x2009;&#x2265;&#x2009;0.05), and no major short-term safety signal was observed. Mean body weight decreased in the 400&#x2009;mg (-2.6&#x2009;kg), 600&#x2009;mg (-1.2&#x2009;kg), and 1,000&#x2009;mg groups (-3.1&#x2009;kg). Compared with placebo, the 1,000&#x2009;mg dose resulted in the largest reductions in body weight (mean difference, -2.30&#x2009;kg; p&#x2009;=&#x2009;0.01) and BMI (mean difference, -0.85&#x2009;kg/m2; p&#x2009;=&#x2009;0.02). The 1,000&#x2009;mg dose showed preliminary efficacy for reducing body weight and BMI over 12&#x2009;weeks compared with placebo, with no major short-term safety signal and no clinically meaningful changes in renal, hepatic, or haematological markers. All reported adverse events were mild. These short-term findings are exploratory and require confirmation in future phase 3 trials with extended follow-up to investigate long-term safety and efficacy.

Humans

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

Histoplasmosis in children: emerging insights and evolving guidelines.

PURPOSE OF REVIEW: This review provides an update on the epidemiology, risk factors, clinical presentation, diagnosis, and management recommendations incorporating recommendations from recent publications including the Infectious Disease Society of America guidelines for the management of pulmonary and disseminated histoplasmosis. RECENT FINDINGS: Updates to the epidemiology of histoplasmosis indicate a broader geographic range than historically defined. Updated guidelines do not recommend routine treatment for asymptomatic, mild and moderate pulmonary histoplasmosis although itraconazole can be offered for immunocompromised children or for prolonged or worsening symptoms. Liposomal amphotericin B is recommended as initial treatment for severe histoplasmosis syndromes (severe pulmonary and disseminated histoplasmosis). Fibrosing mediastinitis, a late complication of histoplasmosis is treated with stenting of vessels and bronchi. Recent studies demonstrate that rituximab (anti-CD20 monoclonal antibody) may stop progression or lead to regression of progressive fibrosis. SUMMARY: Histoplasmosis has manifold manifestations, many of which are self-limited and do not require treatment. Severe histoplasmosis and its complications should be treated with liposomal amphotericin B followed by itraconazole. Clinical trials are needed to assess the efficacy of rituximab for the treatment of fibrosing mediastinitis.

Humans

Integrated bioinformatics analysis reveals cross-talking hub genes and therapeutic agents between sepsis and acute myocardial infarction.

BACKGROUND: Sepsis and acute myocardial infarction (AMI) are two significant diseases that may share overlapping etiological mechanisms. This study aims to systematically identify core genes common to both conditions and to explore their potential as therapeutic targets and drug candidates through an integrative analysis of clinical data and bioinformatics. METHODS: The AMI dataset was obtained from the GEO database, and RNA sequencing data were collected from blood samples of patients with sepsis at our hospital. Common genes were identified using differential expression gene analysis (DEG) and weighted gene co-expression network analysis (WGCNA). Functional enrichment analyses, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, were performed. A protein-protein interaction (PPI) network was constructed, and hub genes were identified using the MCC/Degree algorithm. Diagnostic value was assessed via receiver operating characteristic curve analysis. Immune infiltration patterns, single-cell sequencing data, and molecular docking simulations were employed to evaluate immune relevance and identify potential therapeutic compounds. RESULTS: A total of 417 genes were identified between sepsis and AMI, with enrichment analysis revealing significant involvement in inflammatory responses. Three hub genes-JAK2, MYD88, and TIMP1-were selected for further investigation. ROC curves confirmed their strong diagnostic performance for both diseases. Immune infiltration analysis showed that these core genes were significantly correlated with the infiltration levels of various immune cell types. Molecular docking indicated that quercetin exhibited stable binding affinity with the proteins encoded by these genes. qPCR validation further confirmed the upregulation of these three genes, supporting the anti-inflammatory effects of quercetin as a potential targeted therapy. CONCLUSION: JAK2, MYD88, and TIMP1 were identified as shared core genes in sepsis and AMI. These genes not only serve as potential diagnostic biomarkers but also offer novel targets for developing common therapeutic strategies for both conditions. Furthermore, quercetin emerges as a promising candidate for targeted treatment.

Humans

Updated adjunctive minocycline for schizophrenia: A systematic review and meta-analysis of clinical and cognitive outcomes.

BACKGROUND: Minocycline has been proposed as an adjunctive treatment for schizophrenia due to its anti-inflammatory and neuroprotective properties. However, evidence regarding its efficacy across clinical and cognitive outcomes remains inconsistent. METHODS: A systematic review and meta-analysis of double-blind RCTs was conducted following PRISMA guidelines. PubMed, Web of Science, Embase, Ovid MEDLINE, and the Cochrane Library were searched from January 2000 to August 2025. Eligible studies included patients with schizophrenia receiving adjunctive minocycline plus stable antipsychotics. Primary outcomes were PANSS total and subscale scores and overall cognitive performance. Secondary outcomes included SANS, CDS, CGI, GAF, and seven cognitive domains. Standardized mean differences (SMDs) with 95% CIs were calculated. RESULTS: Ten RCTs involving 895 participants were included. Adjunctive minocycline was associated with improvements in negative symptoms (PANSS negative: SMD = -0.55, 95% CI: -0.96 to -0.13; SANS: SMD = -0.75, 95% CI: -1.00 to -0.49) and overall psychopathology (PANSS total: SMD = -0.49, 95% CI: -0.80 to -0.18). Cognitive benefits were limited to a modest improvement in working memory (SMD = 0.24, 95% CI: 0.08 to 0.39), with no significant effects in other cognitive domains. Subgroup analyses suggested that illness stage, antipsychotic regimen, treatment duration, sample size, and geographic region may contribute to variability in treatment effects. Adverse event rates were comparable between groups. CONCLUSIONS: Adjunctive minocycline may improve negative symptoms and provide modest working memory benefits in schizophrenia. However, the evidence is limited by substantial heterogeneity, potential small-study effects, and inconsistent findings. Although short- to medium-term tolerability appeared comparable to placebo, larger, longer-term RCTs are needed to confirm its efficacy and safety.

Humans

Risk of adverse events in elotuzumab-treated patients with multiple myeloma: a systematic review and meta-analysis.

BACKGROUND: Elotuzumab, an anti-SLAMF7 monoclonal antibody for multiple myeloma (MM), lacks&#xa0;a comprehensive safety profile from meta-analysis. METHODS: We&#xa0;systematically searched PubMed, Web of Science, EMBASE and CENTRAL through February 13, 2025 for randomized controlled trials (RCTs) evaluating elotuzumab in MM. Pooled relative risks(RRs) of adverse events observed in elotuzumab-containing regimens versus control therapies. RESULTS: 6 RCTs (N=1,736) were included. Elotuzumabsignificantly reduced incidence of neutropenia (RR = 0.86, 95% CI: 0.76-0.98), but increased risks of cough (RR = 1.41, 95% CI: 0.96-2.09), pneumonia (RR = 1.30, 95% CI: 1.07-1.59), diarrhea (RR = 1.16, 95% CI: 1.05-1.30), pyrexia (RR = 1.47, 95% CI: 1.10-1.96) and infections (RR = 1.09, 95% CI: 1.03-1.15). No significant differences were observed for anemia, thrombocytopenia, respiratory infections, nausea, appetite loss, back pain, muscle spasms, peripheral edema, insomnia, rash, pruritus, fatigue, or hypokalemia. For grade 3-4 events, elotuzumab was&#xa0;associated with higher risks of lymphopenia (RR = 1.86, 95% CI: 1.31-2.64, p&#x2009;=&#x2009;0.0005, I2 = 9%), diarrhea (RR = 1.47, 95% CI: 1.00-2.17), pneumonia (RR = 1.57, 95% CI: 1.11-2.23), cataracts (RR = 2.87, 95% CI: 1.15-7.21) and infections (RR = 1.30, 95% CI: 1.04-1.62). CONCLUSION: Elotuzumab in MM&#xa0;appears&#xa0;safe but with a specific&#xa0;adverse events pattern :&#xa0;lower neutropenia,&#xa0;but higher respiratory, gastrointestinal, metabolic, and infectious events. Differences may be influenced by longer treatment and corticosteroid use; therefore, interpretation of outcomes such as hyperglycemia and cataracts requires particular caution.

Humans

Whole genome sequencing of unusual Hepatitis C virus subtypes and drug resistance analysis during direct-acting antiviral therapy in India.

INTRODUCTION AND OBJECTIVES: Pangenotypic direct-acting antivirals (DAA) are effective against highly prevalent Hepatitis C virus (HCV) subtypes, but have been clinically validated almost exclusively in high-income countries. Unusual HCV subtypes may carry natural polymorphisms, potentially impacting DAA susceptibility. We conducted full-genome characterization and resistance analysis of unusual HCV subtypes in patients receiving DAA treatment. PATIENTS AND METHODS: In this prospective hospital-based study, eligible patients were screened for anti-HCV antibodies and active infection was confirmed by diagnostic 5'NCR-based HCV RNA detection. Genotyping was performed by core region sequencing, and viral load quantified by real-time PCR. For whole genome sequencing, multiplex primers were designed using alignments of global reference sequences. Sequencing was carried out using the Oxford Nanopore Technology platform. Phylogenetic analysis used multiple sequence alignment and the HCV-GLUE resource for resistance-associated substitution (RAS) analysis. RESULTS: Predominant genotype was genotype 3 in 64.3% (n = 45); genotype 6 in 21.4% (n = 15); and genotype 1 in 14.2% (n = 10). Unusual HCV subtype 6xa was detected in two patients and showed no NS5A resistance mutations. One genotype 3b patient relapsed at 24 weeks post-DAA treatment completion and carried NS5A resistance-associated substitutions 30 K and 31 M both at baseline and at relapse, conferring high-level resistance to NS5A inhibitors. CONCLUSION: This is the first report from India of whole genome sequencing of HCV subtype 6xa. The identification of NS5A resistance mutations in the 3b relapse case underscores challenges for global HCV elimination strategies.

Humans

Therapeutic-drug-monitoring-based ATG Targeted Dosing Strategy in Unmanipulated Haploidentical Haematopoietic Stem Cell Transplantation: a randomized, multicenter, phase 3 clinical trial.

Anti-thymocyte globulin (ATG) has been a standard prophylaxis for graft-versus-host disease (GVHD). However, the pharmacokinetics of ATG in vivo vary significantly, and weight-based fixed dosing may not optimize efficacy while minimizing toxicity. We investigated the clinical results of a therapeutic-drug-monitoring (TDM)-based, dose-optimized ATG strategy versus weight-based fixed dosing in haploidentical haematopoietic stem cell transplantation (NCT05166967). Patients were randomly assigned in a 1:1 ratio to receive a targeted dose of ATG or a fixed dose of 10&#x202f;mg/kg. The primary endpoint was the 365-day graft-versus-host disease-free and relapse-free survival (GRFS). From January 1, 2022, to January 16, 2024, 204 patients were enrolled, with 102 patients in each group. The 365-day GRFS was higher in the targeted dose group (66.7%) than in the fixed dose group (50.0%; hazard ratio [HR], 0.666; 95% confidence interval [CI], 0.4456 to 0.9954; P&#x202f;=&#x202f;0.048). The cumulative incidence of moderate to severe chronic GVHD at day 365 was significantly lower in the targeted dose group (9.8%; 95% CI, 5.0 to 16.5) compared with the fixed dose group (22.5%; 95% CI, 15.0 to 31.1; P&#x202f;=&#x202f;0.026). Fewer grade 3-5 infections were reported in the targeted dose group (44.1%) than in the fixed dose group (70.6%; P&#x202f;<&#x202f;0.001). More patients in the targeted dose group achieved optimal ATG exposure (P&#x202f;=&#x202f;0.007) and superior CD4+ T-cell reconstitution (P&#x202f;=&#x202f;0.002). These findings support the clinical utility of a TDM-based individualized ATG dosing strategy that balances efficacy and toxicity for GVHD prophylaxis in allogeneic stem cell transplantation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05166967.

Humans

Assessing the threat of Bacillus cereus: From toxin characterization to modern detection strategies.

Bacillus cereus is a spore-forming pathogen responsible for both diarrheal and emetic foodborne illnesses worldwide. Its significance in food safety has received growing attention. Recent advances, including the discovery of novel virulence factors and the development of emerging detection technologies, have provided new insights into its pathogenic mechanisms and surveillance strategies. This review critically examines the global burden of B. cereus infections, and molecular mechanisms of its major virulence factors, and the performance characteristics of current detection knowledge gaps such as the viable-but-non-culturable state and regulatory blind spots for emetic toxins, and discuss unresolved challenges in clinical management. By integrating epidemiological, microbiological, and technological perspectives with critical lens, this review aims to provide a valuable reference for future research and food safety practices.

Bacillus cereus

Metal-organic frameworks nanozyme-integrated portable microneedle patch for visual bacterial monitoring in meat.

Foodborne microbial contamination is a major global health concern, with conventional methods often being time-consuming and complex. Herein, we developed a novel portable biosensor by integrating microneedle patch technology and a metal-organic framework (Fe/Cu-NBDC MOF) nanozyme, enabling rapid, on-site, visual detection of bacteria in meat. The sensing system works by encapsulating aptamer-functionalized MOF nanozymes within a hydrogel patch, where their catalytic sites are initially blocked by the aptamer. In the presence of Staphylococcus aureus (S. aureus) as the target, the specific aptamer's binding to bacteria exposes numerous catalytic sites, further activating the chromogenic reaction of the tetramethylbenzidine&#x2011;hydrogen peroxide (TMB-H&#x2082;O&#x2082;) system, enabling visual detection of S. aureus. The biosensor demonstrates a detection limit of 82&#xa0;CFU/mL with excellent specificity to successfully apply to commercial mutton. By integrating sampling, enrichment, and visual detection into a single compact device, this platform offers a practical, efficient solution for rapid on-site screening of foodborne pathogens.

Biosensing Techniques

Acetylcholine signaling regulates osmotic stress adaptation in the phytopathogen Dickeya solani.

Plants impose strong selective pressures that shape both the composition and functional potential of plant microbiomes. The adaptation of plant-associated bacteria to their hosts relies on an extensive repertoire of signal transduction systems that sense plant-derived molecules and dynamically adjust bacterial physiology and metabolism within the holobiont. These signals include key plant signaling compounds that regulate processes essential for plant-microbe interactions. Among them, acetylcholine is emerging as an important signaling molecule in both plants and bacteria. Here, we demonstrate that acetylcholine regulates the expression of the osmotic stress response betIBA gene cluster in the important phytopathogen Dickeya solani, where it plays an important role in osmoprotection. We show that the TetR-family transcriptional regulator associated with this pathway, BetIDs, recognizes acetylcholine as well as choline and trimethylamine. These three ligands differentially induce betIBA transcription in a manner that correlates with their binding affinities. Ligand binding does not affect BetIDs binding to the bet promoter or its oligomeric state. Instead, it induces pronounced changes in the secondary structure of BetIDs, with the magnitude of these conformational changes being ligand-dependent. We further show that quorum sensing modulates osmotic stress tolerance in D. solani by regulating the expression of the Bet pathway. The Bet system is required for the full virulence of D. solani, particularly in chemically complex plant tissues. Phylogenetic analyses reveal that the BetIBA system is widely distributed among plant-associated Pseudomonadota, collectively supporting its importance for bacterial survival and adaptation in plant-related environments.

Osmotic Pressure

A chromosomal gtrB homolog and dam differentially contribute to dry-heat and high hydrostatic pressure resistance in Salmonella enterica.

Salmonella enterica can persist in low-moisture foods and shows enhanced dry-heat resistance under low water activity, posing significant food safety challenges. However, the genetic basis of extreme dry-heat resistance and its relationship with other processing stresses remain unclear. In this study, twelve S. enterica strains were screened for dry-heat treatment at 60&#xa0;&#xb0;C and 80&#xa0;&#xb0;C, with S. Infantis CICC21649 identified as the most resistant strain. Comparative genomics and transcriptional analysis identified candidate genes related to envelope integrity and regulation, including gtrB and dam. Deletion of the chromosomal gtrB homolog reduced dry-heat resistance, producing an additional 0.91-log10 reduction relative to the parent strain at 80&#xa0;&#xb0;C. Deletion of dam caused broader stress sensitivity, reducing resistance to both dry heat and high hydrostatic pressure, with the stronger phenotype observed under high hydrostatic pressure. Proteomic analysis of the chromosomal gtrB homolog mutant revealed broad alterations in envelope-associated proteins, transport functions, oxidative stress pathways, and central metabolism under dry-heat stress. These findings indicate that the chromosomal gtrB homolog is an important contributor to extreme dry-heat resistance, whereas dam contributes to resistance against both dry-heat and high hydrostatic pressure, likely through a broader regulatory role in stress adaptation. These results reveal distinct structural and regulatory layers underlying stress adaptation in S. enterica and provide practical guidance for low-moisture food processing by highlighting the need to account for strain-dependent and stress-specific resistance during process validation.

Hydrostatic Pressure

Routine methods misidentify Serratia spp.: Limitations of MALDI-TOF MS revealed by whole-genome sequencing.

Accurate species-level identification within the genus Serratia remains challenging due to extensive phenotypic overlap and high genomic relatedness among closely related and recently described taxa. This study presents an evaluation of routine and genome-based identification approaches applied to clinical Serratia isolates, integrating phenotypic assays, MALDI-TOF MS (Bruker Daltonics), 16S rRNA gene sequencing, and Whole-Genome Sequencing (WGS). A total of 103 isolates collected from a teaching hospital were analyzed. WGS was performed on a subset of isolates. Conventional biochemical methods classified all isolates as Serratia marcescens, whereas MALDI-TOF MS identified 60.1% as S. marcescens, 11.6% as S. ureilytica, and 28.1% just at the genus level. Peak analysis from MALDI-TOF MS revealed specific peaks associated with S. marcescens and S. ureilytica, but limited discriminatory power. WGS of six isolates initially identified as S. ureilytica by MALDI-TOF MS revealed reclassification as Serratia sarumanii (n = 5) and Serratia montpellierensis (n = 1), supported by Average Nucleotide Identity (ANI), Average Amino Acid Identity (AAI), and Digital DNA-DNA Hybridization (dDDH) thresholds. In contrast, 16S rRNA analysis showed limited species-level resolution. Phylogenomic and SNP-based analyses confirmed these classifications with strong support. Overall, this study underscores the critical role of high-resolution genomic approaches for precise species identification and highlights the need for continuous expansion and curation of MALDI-TOF MS reference databases to support reliable clinical diagnostics and epidemiological surveillance of emerging Serratia species.

Spectrometry, Mass, Matrix-Assisted Laser Desorpti

Transcriptomic responses of gill and intestinal tissues in Nile tilapia (Oreochromis niloticus) to bacterial infection following sequential nanoimmersion and hydrogel-based multivalent vaccination.

Bacterial pathogens, including Flavobacterium oreochromis, Aeromonas veronii, Streptococcus agalactiae, and Edwardsiella tarda, represent major infectious threats to Nile tilapia (Oreochromis niloticus). A multivalent vaccination strategy integrating cationic nanoemulsion immersion with oral hydrogel boosters was developed to investigate tissue-specific immune responses at the transcriptomic level. Gill tissues were collected following immersion challenge and intestinal tissues following intraperitoneal injection challenge, reflecting the physiologically relevant infection biology of each pathogen and the mechanistic rationale of each delivery platform. RNA sequencing (RNA-seq) generated high-quality datasets (mapping rate&#xa0;>&#xa0;81.64%) with strong concordance to quantitative real-time PCR (qRT-PCR) validation (r&#xa0;=&#xa0;0.83). Comparative transcriptomic analysis revealed distinct yet complementary immune signatures between tissues. Gill transcriptomes were enriched in phagosome, focal adhesion, extracellular matrix-receptor interaction (ECM-receptor interaction), and cytokine-cytokine receptor interaction pathways, accompanied by increased expression of major histocompatibility complex class I/II (MHC class I/II), mannose receptor, &#x3b1;V&#x3b2;3 integrin, and calnexin, indicating innate activation, enhanced phagocytic capacity, epithelial barrier reinforcement, and adaptive immune coordination. Intestinal transcriptomes showed predominant enrichment of adaptive immune pathways, including the intestinal immune network for immunoglobulin (Ig) production, Forkhead box O (FoxO) signaling, and mitogen-activated protein kinase (MAPK) signaling, with increased expression of T-cell receptor (TCR), inducible T-cell co-stimulator ligand (ICOS-L), C-X-C chemokine receptor type 4 (CXCR4), and polymeric immunoglobulin receptor (pIgR), reflecting T and B cell coordination, lymphocyte trafficking, and mucosal immunoglobulin transport, alongside innate engagement through phagosome pathway enrichment. Shared upregulation of MHC class II, B-cell receptor (BCR) signaling, integrin alpha M (ITGAM), and immunoglobulin-associated components across both tissues suggests coordinated mucosal immune activation through a conserved immune module, warranting direct experimental validation. Collectively, these findings provide transcriptomic evidence that this vaccination strategy elicits an integrated, tissue-specialized immune response, advancing mechanistic understanding of gill and intestinal immunity in vaccine-induced protection of teleost fish.

Animals

Dynamics of antibiotic resistance genes co-occurrence with pathogenic and non-pathogenic bacteria throughout wastewater treatment processes.

Wastewater treatment plants (WWTPs) are recognized hotspots for antibiotic resistance genes (ARGs) and pathogenic bacteria. Despite advancements in treatment technologies, the persistence of ARGs and pathogenic bacteria remains a concern. In this study, we analyzed the dynamic changes in ARGs and bacterial communities throughout the treatment processes within an anaerobic-anoxic-oxic (AAO) WWTP over one week by using HT-qPCR coupled with 16S rRNA gene amplicon sequencing. The connectedness index, based on network analysis, showed that the dynamics of ARGs and mobile genetic elements (MGEs) were more strongly associated with potentially pathogenic bacteria than with non-pathogenic bacteria, suggesting that ARG immigration and dissemination in the WWTP were likely driven by potentially pathogenic taxa. The AAO treatment significantly reduced ARGs in final effluent (EF) (&#x223c;64 %) and residual sludge (RS) (&#x223c;81 %); however, potential hosts of ARGs such as Comamonas testosteroni and Clostridioides difficile persisted with minimal changes in relative abundance and remained detectable in EF and RS. Notably, the abundance of ARGs was lower in RS than in EF, and source tracking analysis identified influent as the primary source of ARGs and potentially pathogenic taxa in EF, underscoring the greater health risks associated with effluent discharge.

Wastewater

Coordinated use of three homocysteine methyltransferases supports l-methionine biosynthesis and environmental adaptation among plant-associated bacteria.

Plant pathogens colonize multiple plant-associated habitats throughout their life cycle, encountering distinct nutrient conditions and microbial communities. l-methionine is required for bacterial growth and environmental adaptation. However, how plant pathogens coordinate l-methionine biosynthetic pathways to adapt to different plant-associated environments remains poorly understood. Here, using the plant pathogen Xanthomonas campestris pv. campestris strain XC1 as a model, we show that three homocysteine methyltransferase pathways allow XC1 to catalyze the final step of l-methionine biosynthesis using different methyl donors and cofactors under different environmental conditions. Bioinformatic and transcriptional analyses identified three homocysteine methyltransferase-associated operons in XC1, mesMXD, mmuPM, and metHRHaHb, corresponding to the MesD-, MmuM-, and MetHaHb-dependent pathways, respectively. MesD uses an endogenously synthesized methyl donor and functions as the dominant homocysteine methyltransferase under l-methionine-limiting conditions, supporting bacterial growth, intracellular l-methionine accumulation, and full virulence. Furthermore, MmuM enables XC1 to use plant-derived S-methylmethionine for l-methionine biosynthesis, whereas MetHaHb enables XC1 to use vitamin B12 supplied by a neighboring bacterium for l-methionine biosynthesis in co-culture. Expression analyses showed that mesMXD was the only homocysteine methyltransferase-associated operon that responded to l-methionine availability, and its expression also decreased when S-methylmethionine- or vitamin B12-dependent pathways supported l-methionine biosynthesis. Comparative genomic analysis further showed that the three-homocysteine methyltransferase configuration is conserved in Xanthomonas and is also present in other plant-associated bacteria. Together, these findings show that a plant pathogen can coordinate endogenous, plant-derived, and microbially supported homocysteine methyltransferase pathways to maintain l-methionine biosynthesis, providing a metabolic strategy for adaptation to plant-associated environments.

Methionine