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PubMed2026

Management of neonates born to mothers with reactive serologic tests for syphilis.

PURPOSE OF REVIEW: The dramatic resurgence of maternal and congenital syphilis in the United States highlights the need for their optimal management as syphilis in pregnancy can result in substantial neonatal morbidity and mortality. This review summarizes current epidemiology and discusses guidance on the management of neonates born to mothers with reactive serologic tests for syphilis. RECENT FINDINGS: Timely communication with local health department professionals is essential for optimal management of mothers with reactive serologic tests for syphilis and their neonates. Knowledge of maternal syphilis treatment history by partnering with local jurisdictions can circumvent much of the incertitude surrounding neonatal management. All neonates born to mothers with reactive serologic tests for syphilis should be tested using a nontreponemal ('lipoidal antigen') test. However, a reactive test may only indicate maternal nontreponemal IgG antibodies that are transferred transplacentally to the fetus. Therefore, neonatal management depends on maternal history and treatment for syphilis as well as clinical, laboratory, and radiographic findings in the neonatal evaluation. Existing management algorithms are complex, highlighting the need for a more practical, yet safe, approach. SUMMARY: A neonatal management guideline is proposed that may simplify the management of neonates born to mothers with reactive serologic tests for syphilis while advocating for expanded use of single-dose benzathine penicillin G therapy.

Humans↗

PubMed2026

Comparison of short-term clinical outcomes and patient satisfaction between intraoral scanning and conventional impressions for complete-arch implant prostheses: a pilot RCT.

OBJECTIVE: To compare framework passive fit, subjective evaluations, and short-term clinical outcomes between conventional impressions (CI) and intraoral scanning (IOS) for complete-arch implant-supported fixed dental prostheses (CIFDPs). METHODS: In this randomized controlled trial, 22 patients were allocated to the CI or IOS groups. All participants received a definitive one-piece CIFDP. The primary outcome was framework passive fit, assessed using the Vision and Tactile Score (V&T score), which included framework lift-off, the single-screw test, the full-screw test, smoothness of screw insertion, and radiographic gap assessment. Secondary outcomes included operator evaluation, patient satisfaction using a visual analog scale (VAS), early implant survival, marginal bone loss (MBL), modified Plaque Index (mPII), and complications at the 6-month follow-up. RESULTS: Twenty-two patients were enrolled (CI: n = 11; IOS: n = 11), and one patient in the CI group was lost to follow-up. No statistically significant difference in the V&T score was observed between the CI and IOS groups (4.66 ± 0.17 vs. 4.65 ± 0.28; P = 0.93). The operator reported greater nervousness during the CI procedure than during IOS (21.82 ± 15.69 vs. 8.64 ± 7.47; P < 0.05). Patients in the CI group reported significantly greater discomfort, including nausea and anxiety, than those in the IOS group (P < 0.05). At the 6-month follow-up, the early implant survival rate was 100% in both groups. No significant differences were found between the groups in MBL (0.09 ± 0.09 vs. 0.06 ± 0.10 mm; P = 0.43) or mPII (0.10 ± 0.12 vs. 0.10 ± 0.28; P = 0.99). CONCLUSION: IOS and CI achieved comparable short-term clinical outcomes in patients who met the predefined inclusion criteria, including controlled implant number, spacing, and angulation. IOS provided a more favorable experience for both operators and patients. CLINICAL SIGNIFICANCE: In complete-arch implant restorations, intraoral scanning may provide clinical outcomes comparable to those of conventional impressions while improving patient comfort.

Humans↗

PubMed2026

Metagenome-scale modeling to assess microbiome metabolic complementarity for precision microbiota transplantation therapies.

Fecal microbiota transplantation (FMT) holds therapeutic promise beyond recurrent Clostridioides difficile infection, but clinical outcomes remain unpredictable and donor-selection strategies remain limited, in part because the role of donor‒recipient metabolic interactions in shaping the post-FMT community remains poorly understood. Here, we leverage metagenome-scale metabolic modeling to quantify metabolic niche complementarity between donor and recipient microbiomes and predict post-FMT community composition. Using MICOM-derived metabolic models, we show that donor genomes whose metabolic flux profiles are more dissimilar from the recipient community colonize at significantly higher rates in a murine FMT model. In a human IBS trial, the same metric predicted post-FMT community composition via leave-one-out cross-validation and captured known disease-associated alterations in short-chain fatty acid, sulfur, and gas metabolism. We then performed 2,548 in silico FMT simulations between IBS-D/M patients and donors from the OpenBiome biobank to evaluate personalized donor screening, identifying super-donors characterized by high taxonomic diversity, broad metabolic niche coverage, and community interaction networks dominated by cross-feeding rather than competition. Together, these results support metabolic niche complementarity as a potential determinant of post-FMT community composition and provide a mechanistic basis for evaluating donor-recipient metabolic compatibility. This framework offers a scalable approach for generating testable hypotheses for personalized donor selection.

Fecal Microbiota Transplantation↗

PubMed2026

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 β-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 α-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↗

PubMed2026

Transformation of antibiotics mediated by iron-bearing minerals: A review.

Iron-bearing minerals are ubiquitous in water, sediments and soil, where their surface chemical properties and redox activity can play an important role in degradation of trace antibiotics. This review systematically summarizes the roles of various iron-bearing minerals in chemical transformation and microbial degradation of antibiotics and reaction mechanisms involved, and refines the critical idea for iron-driven control of antibiotics with trace level in natural environment. Overall, antibiotics removal in the presence of iron-bearing minerals involves combination of adsorption, surface oxidative degradation, photo-induced degradation, Fenton-like reaction and microbial degradation. Adsorption of antibiotics by Fe(III)-minerals involves electrostatic interaction, complexation, H-bonding, π-π interaction and hydrophobic interaction. Adsorbed antibiotics form complexes with Fe(III)-minerals, undergoing electron transfer to generate radical intermediates, subsequently generating final products through hydroxylation, dealkylation, and deamination. Additionally, Fe(III)-minerals can be excited to produce electrons and holes under sunlight and to produce antibiotics-degrading hydroxyl radical through O2 reduction, H2O oxidation and ligand-to-metal charge transfer. Reduced iron minerals can activate oxygen to participate in Fenton-like degradation reactions. Finally, antibiotics are mainly removed by bio-driven Fenton reaction and direct enzyme biodegradation. The presence of iron-bearing minerals can promote antibiotics microbial degradation by providing nutrients for microorganisms or by changing microbial activity and microbial community structure. Existing problems and future research directions are identified. New insights for application of iron-bearing minerals in transformation of antibiotics are proposed. The work aims to suggest new methods and insights for pollution control and remediation of emerging contaminants including trace antibiotics in the natural environment.

Anti-Bacterial Agents↗

PubMed2026

Integrated assessment of biocontrol potential and genome analysis of endophytic Bacillus velezensis MGL-B1 against mango stem-end rot.

Mango stem-end rot is a globally significant postharvest disease that severely threatens the mango industry, primarily caused by Botryosphaeria dothidea. However, information on biocontrol agents targeting this pathogen in mango remains limited. In this study, we isolated and identified a strain of Bacillus velezensis MGL-B1 from mango leaf tissues for the first time, which exhibited broad-spectrum antifungal activity. Both in vitro and in vivo assays demonstrated that MGL-B1 effectively inhibited the growth of B. dothidea, with an in vivo biocontrol efficacy reaching 83.72 ± 5.10%, comparable to that of the commonly used chemical fungicide thiabendazole. Further mechanistic analysis revealed that MGL-B1 acts by directly disrupting the integrity of the pathogen's mycelial cell membrane. In addition, its released volatile organic compounds (VOCs) also displayed significant antifungal activity, with components such as 2-nonanone, 2-nonanol, and phenylethyl alcohol being confirmed to exert antifungal effects in in vitro fumigation assays. qPCR analysis showed that MGL-B1 treatment significantly upregulated the transcriptional levels of genes involved in plant-pathogen interaction, phenylpropanoid biosynthesis, and antioxidant defense pathways in mango fruits, with upregulation folds of 16.32, 37.19, and 75.93, respectively; meanwhile, the expression of browning-related genes such as polyphenol oxidase (PPO) was markedly suppressed. Whole-genome sequencing further revealed 14 biosynthetic gene clusters for antimicrobial compounds, including five unknown gene clusters. Collectively, B. velezensis MGL-B1 represents a promising biocandidate strain with multiple antifungal mechanisms and excellent control efficacy, providing a valuable resource for green and sustainable management of mango diseases.

Mangifera↗

PubMed2026

Characterization of the Immune Response after Oral Cholera Vaccination (OCV) and Effects of Mycophenolate Mofetil on Priming of this Immune Response-A Randomized, Placebo-Controlled Trial.

Mycophenolate mofetil (MMF) is an immunosuppressive drug widely used by solid organ transplant recipients. Although it is known that MMF suppresses immune responses, its exact effects on specific vaccinations have not been investigated yet. Mucosal vaccinations are increasingly used, such as a cholera vaccination consisting of two oral immunizations (oral cholera vaccination; OCV). This study aimed to investigate the specific immunosuppressive effects of MMF use during the first dose of OCV in a randomized, placebo-controlled trial in healthy volunteers. Moreover, the study aimed to characterize the immune response provoked by OCV in detail. This randomized, placebo-controlled, single-blind trial included 16 healthy volunteers, each receiving two doses of Dukoral® and an intranasal rechallenge. Outcome measures were serum antibody responses (IgA and IgG) and IgA levels in saliva. Additionally, peripheral blood mononuclear cells (PBMCs) of participants were investigated for ex vivo cytokine production and expression of tissue-specific homing markers after OCV. There were considerable serum IgA and IgG responses after vaccination. MMF-treated volunteers still showed a significant cholera antibody response, though data suggest a potential suppression by MMF without reaching statistical significance. There was no substantial IgA response in saliva. Investigation of PBMCs from OCV-treated participants showed a Th2 skewing with increased ex vivo production of TNF, IL-2, IL-5, IL-13, and IL-22 compared to the placebo group. Taken together, this study provides a framework for future clinical pharmacology studies building on OCV as a challenge model and for further investigation of specific effects of MMF on mucosal vaccination responses.

Humans↗

PubMed2026

Morphology-engineered NiFe@C nanocages boosting electrochemical quantification of ractopamine in meat samples.

It is essential to acquire efficient electrocatalysts to develop ractopamine (RAC) electrochemical sensors. Herein, we report the synthesis of a series of carbon coated NiFe alloy nanostructures (e.g., NiFe@C nanoparticles, nanocubes and nanocages) using NiFe Prussian blue analogue (PBA) as the precursor. The NiFe@C nanocages exhibited the best electrocatalytic performance for RAC sensing. This is attributed to the embedded NiFe alloy nanoparticles that provide abundant active sites, and the unique nanocage structure facilitates electron transfer pathways while offering a high specific surface area. The resulting sensor achieves a low detection limit (LOD) of 54 nM (S/N = 3) within a linear range of 0.2-12 μM. Moreover, the sensor demonstrates good reproducibility, stability, and excellent long-term stability. Practical applicability was confirmed in meat samples, yielding satisfactory recovery rates ranging from 98% to 108%. A feasible strategy was introduced herein for rational design of metal@carbon electrocatalysts.

Phenethylamines↗

PubMed2026

"Clinical efficacy and expression of antimicrobial resistance genes after using a novel herbal mouthwash compared to chlorhexidine: A Randomised controlled trial in generalised gingivitis patients".

OBJECTIVES: Chlorhexidine, the gold-standard mouthwash, has several disadvantages, like promotion of antimicrobial resistance. Herbal mouthwashes are emerging as alternatives to chlorhexidine. However, its impact on antimicrobial resistance remains unclear. The aim of the study was to compare the clinical efficacy and the expression of antimicrobial resistance genes of chlorhexidine with a novel herbal mouthwash. DESIGN: Sixty patients with generalised gingivitis were randomly assigned to two groups using block randomisation. After professional mechanical plaque removal patients were instructed to use either chlorhexidine or a novel herbal mouthwash (patented composition) for two weeks. Tetracycline resistance (tetM) and macrolide efflux (mefI) gene expression in subgingival plaque were analysed using real-time polymerase chain reaction. Intragroup comparisons were performed with a paired t-test and Wilcoxon signed-rank test for parametric and nonparametric data. Intergroup comparisons employed unpaired t-test, chi-square test, and Mann-Whitney test. RESULTS: A significant reduction in bleeding, plaque, pocket depth and and patient reported outcomes were noticed in both groups. But reduction in plaque was more significant in chlorhexidine group. tetM and mefI genes significantly upregulated in the chlorhexidine group, while it was downregulated with herbal mouthwash (fold change 1.79 ± 0.74 and 0.60 ± 0.43 for tetM, and 1.83 ± 0.87 and 0.51 ± 0.44 for mefI). However, patients' perception of taste, freshness, and overall satisfaction was better in the chlorhexidine group. CONCLUSIONS: The increased expression of antimicrobial resistance genes following chlorhexidine use warrants careful consideration. Herbal mouthwash is an effective, safer alternative with comparable clinical benefits and less impact on antimicrobial resistance.

Humans↗

PubMed2026

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 g/kg, designated as p0, p25, p50, p75, and p100, respectively, for 56 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 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 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-κB signaling pathways suggested that 5.0 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 g/kg dietary chitosan is suitable for juvenile largemouth bass, and 5.0 g/kg may serve as an effective pre-transport dietary inclusion level.

Animals↗

PubMed2026

Nasopharyngeal Carriage Rate, Risk Factors, and Co-Resistance Patterns of Methicillin-Resistant Staphylococcus aureus in Ethiopia: Systematic Review and Meta-Analysis.

Methicillin-resistant Staphylococcus aureus (MRSA) nasopharyngeal carriage is a major global health concern linked to severe infections and transmission. However, comprehensive evidence on the burden of MRSA carriage, antimicrobial resistance, and associated risk factors in Ethiopia remains limited. This study aimed to estimate pooled prevalence, resistance pattern, and determinants of nasopharyngeal MRSA carriage. PubMed, ScienceDirect, Scopus, Web of Science, Google Scholar, and gray literature were searched for cross-sectional studies published between January 2015 and December 2025. Two groups of reviewers screened studies based on predefined criteria. The risk of bias was assessed using the Joanna Briggs Institute tool. Pooled prevalence and resistance proportions were estimated using a random-effects model, and pooled odds ratios (ORs) were calculated using the Mantel-Haenszel method. Heterogeneity and publication bias were assessed, and a sensitivity analysis was conducted. A total of 1040 records were identified, and 20 studies (6869 participants) were included. The pooled carriage prevalence was 7.3% (95% CI, 5.0-10.8), with substantial heterogeneity (I2 = 95.5%). Resistance was highest to tetracycline (55.75%) and lowest to clindamycin (12.66%). Increased odds of carriage were associated with prior hospitalization (OR, 3.49) and antibiotic use (OR, 2.35). Inconsistent variable coding across included studies limited the inclusion of other potential risk factors. Evidence of publication bias was detected, suggesting that the pooled prevalence should be interpreted with appropriate caution. The findings indicate a considerable burden of MRSA and highlight the need for strengthened antimicrobial stewardship, improved surveillance, and targeted prevention efforts in higher-risk populations. This review was registered in PROSPERO (CRD420251047192).

Ethiopia↗

PubMed2026

Comparison of Keverprazan-based versus esomeprazole-based dual therapy for initial treatment of Helicobacter pylori infection: a prospective, multicenter, randomized controlled trial.

BACKGROUND: Keverprazan offers a new perspective for Helicobacter pylori eradication. This study compared 14-day keverprazan-amoxicillin therapy with esomeprazole-amoxicillin therapy to explore a superior treatment strategy. METHODS: This was a prospective, open-label, multicenter, randomized controlled trial in adult patients with treatment-naive H. pylori infection. Participants were randomly assigned to receive either 14-day of KA therapy (Keverprazan 20 mg b.i.d plus amoxicillin 1 g t.i.d) or 14-day of EA therapy (Esomeprazole 40 mg b.i.d plus amoxicillin 1 g t.i.d). The primary outcome was the H. pylori eradication rate. Secondary outcomes were the incidence of adverse events and patient adherence. RESULTS: A total of 264 patients were enrolled in the study. In the intention-to-treat (ITT) analysis, the eradication rates for the 14-day KA group and the 14-day EA group were 87.9% and 80.3%, respectively (p = 0.092); in the modified intention-to-treat (mITT) analysis, the eradication rates were 92.1% and 86.2%, respectively (p = 0.135); and in the per-protocol (PP) analysis, the eradication rates were 93.5% and 88.3%, respectively (p = 0.155). Non-inferiority was confirmed between the two groups (all p < 0.001). Adverse events and patient adherence were similar between the two groups. CONCLUSION: For treatment-naive H. pylori infection, the 14-day KA therapy is non-inferior to EA therapy. Given its good tolerability, pharmacogenomic independence, and potent acid suppression, KA is a rational first-line alternative to EA in the Chinese population.

Humans↗

PubMed2026

Design of an innovative framework based hybrid catalyst for simultaneous and sensitive monitoring of food additive and preservative of vanillin and nitrite in direct samples.

As vanillin (VAN) and nitrite (NIT) contamination in the food chain poses substantial threats to environmental and public health, rapid and portable detection is essential. The present study presents the first electrochemical sensor report based on a hybrid composite of Ni-TPA-MOF and MoS2/Co3O4. The oxidation of VAN and NIT exhibited sharp peaks and less over-potential on Ni-TPA-MOF/MoS2/Co3O4/GCE than on control electrode surfaces. On modified composite electrode surfaces, pH and scan rate were investigated for VAN and NIT. Further, the oxidation current exhibited high linearity at VAN and NIT concentrations of 5 nM-1000 μM and 3 nM-1250 μM, with detection limits of 0.102 nM and 0.073 nM (S/N = 3). We also applied anti-interfering ability (five/ten-fold excess of co-interfering compounds) and practical tests to various food-based real samples, with high recoveries of 98.85-102.41%. This study highlights the catalytic properties of Ni-TPA-MOF/MoS2/Co3O4 and demonstrates the sensor as a promising tool for food safety.

Benzaldehydes↗

PubMed2026

Proteomics in environmental pollution research: Advances, challenges, and future directions.

Environmental proteomics has emerged as a powerful approach for elucidating the molecular mechanisms underlying pollutant-induced biological effects. Although this field has developed rapidly, the systematic review of recent proteomics applications in environmental pollution research remains limited. This review explored the emerging roles of toxicoproteomics in biomarker discovery and mechanistic elucidation, as well as ecotoxicoproteomics in ecological risk assessment and bioremediation strategies. Here, we review the field, highlighting recent trends such as the integration of proteomics with genomics, transcriptomics, and metabolomics to provide a comprehensive view of biological responses to environmental stressors. We further discuss the growing application of artificial intelligence in improving proteomics data interpretation and accelerating biomarker discovery. In addition, recent technological advances in environmental proteomics are highlighted, including next-generation tissue microarray proteomics, nanoscale proteomics, single-cell proteomics, and spatial proteomics. Despite its potential, proteomics faces challenges, such as high operational costs, computational complexity in analysis, and technical limitations in low-abundance protein detection. We propose that the convergence of proteomics with artificial intelligence and multi-omics approaches offers promising solutions to these challenges, enhancing the practical application of proteomics in environmental monitoring and risk assessment.

Proteomics↗

PubMed2026

Recent advances in Strongyloides screening, diagnostics, therapeutics, and management.

PURPOSE OF REVIEW: Strongyloidiasis affects an estimated 30-100 million people globally and can have life-threatening consequences in immunocompromised hosts, yet it remains underdiagnosed due to limited access and performance of available diagnostics. Novel assays and anthelmintics may reshape screening, diagnosis, treatment, and prevention for at-risk populations. RECENT FINDINGS: Advances in molecular diagnostics coupled with robust stool extraction methods have supplanted traditional parasitologic methods in settings where nucleic acid amplification is feasible. Transition from standard immunoglobulin G (IgG)-based immunoassays to the new IgG- and IgG4-based rapid diagnostic tests using recombinant Strongyloides stercoralis nematode immunodominant E antigen (NIE) and/or S. stercoralis immunoreactive antigen (SsIR) has facilitated serologic screening at the point of care. The World Health Organization now conditionally recommends community-wide ivermectin mass drug administration in highly endemic settings. Regarding new treatment options, moxidectin is noninferior to ivermectin with 93-94% cure rates and a longer half-life, while emodepside shows 80-90% predicted cure rates in early trials and offers a mechanistically distinct option. Understanding of immunosuppressed populations at risk for hyperinfection has expanded, prompting updated screening recommendations. SUMMARY: Serologic and molecular tools are improving screening and diagnosis, and moxidectin and emodepside may broaden treatment options, but data in severe disease and special populations remain limited. Priorities include harmonized screening algorithms and prospective studies in high-risk groups.

Humans↗

PubMed2026

In situ product monitoring in heterogeneous reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3: Effect of environmental factor and particle property.

Gas-particle reactions represent an important atmospheric heterogeneous transformation process for organic amines (OAs). Environmental factors and particle properties may impact the gas-particle reaction products. Although the products from gas-particle reactions can be monitored by various in situ techniques, related data remain scarce. Here, the interfacial and gaseous products from the reaction of trimethylamine on Fe2O3/Fe(NO3)3 particles under light irradiation with mixed NO2, O2, SO2 and H2O were monitored using in-situ diffuse reflectance Fourier transform infrared spectroscopy and proton transfer reaction time-of-flight mass spectrometry. Dark reaction of gaseous trimethylamine on Fe2O3/Fe(NO3)3 generated two interfacial products types: N-containing ones (CH3NCH2, CH3NO2, (CH3)2NCHO, and CH3N(OH)CHO) and N-free ones (alcohols, aldehydes and acids), both accumulating with reaction progression. Light irradiation and O2 oxidation enhanced formation of these products, while NO2 promoted the production of CH3NO2 and (CH3)2NCHO. H2O and SO2 occupied the active sites of particles to inhibit the formation of all products. Compared to Fe(NO3)3, Fe2O3 showed absolute dominance in contribution to the formation of products. Considering the smaller particle size of Fe2O3 and excess Fe(NO3)3, the physical mixing of them reduced the generation of interfacial products. Furthermore, gaseous products of CH3OH, HCHO, CH3CHO, HCOOH and CH3COOH detection clarified the N-free interfacial products. The presence of Fe(NO3)3 inhibited the formation of HCOOH and favored the formation of CH3CHO in the gas phase. By combining product information with thermodynamic calculations, the heterogeneous reaction pathways of trimethylamine were tentatively proposed. These findings provide a guiding significance for the migration of OAs in real atmospheric environment.

Methylamines↗

PubMed2026

Hippocampal teneurin-4 knockdown promotes depression-like behavioral phenotypes by disrupting oligodendrocyte differentiation in mice.

Depression is one of the most prevalent mental disorders worldwide. The limited clinical efficacy of current antidepressants highlights identifying new therapeutic targets. Emerging evidence suggests that dysfunction of oligodendrocyte lineage cells contributes to the pathophysiology of depression. Teneurin-4 (Tenm4), a transmembrane protein that promotes oligodendrocyte differentiation and myelination, has been implicated in psychiatric disorders in genome-wide association studies; however, its causal role remains unclear. To determine whether Tenm4 contributes to depressive-like behavioral phenotypes, we examined Tenm4 protein expression in mice exposed to repeated forced swimming stress and generated hippocampal Tenm4 knockdown (Tenm4KD) mice. Chronic stress reduced Tenm4 expression levels in the hippocampus. Mice with hippocampus-specific Tenm4KD exhibited depressive-like behaviors, accompanied by reduced hippocampal myelin basic protein. Importantly, administration of clemastine, a myelin formation promoter, inhibited the reduction of myelin and attenuated depression-like behavioral phenotypes. Immunohistochemical analysis showed that Tenm4KD significantly decreased the number of mature oligodendrocyte cells and increased in the number of oligodendrocyte precursor cells, without changes in the total number of oligodendrocyte lineage cells. This study provides the first evidence that hippocampal Tenm4 deficiency induces depression-like behavior phenotypes through impaired oligodendrocyte differentiation and promoting demyelination. Our results identify Tenm4 as a molecular regulator of stress-induced behavioral phenotypes and suggest that it might represent a potential therapeutic target for mood disorders associated with demyelination.

Animals↗

PubMed2026

Metabolic Stress Testing Reveals Persistent Lipid-Handling Dysfunction in Women With Polycystic Ovary Syndrome Despite Exercise Training.

AIM: Polycystic ovary syndrome (PCOS) is associated with insulin resistance and metabolic dysfunction, yet baseline metabolomic studies show inconsistent findings. We investigated whether metabolic abnormalities in PCOS emerge under physiological stress and how these responses are modified by exercise training. MATERIALS AND METHODS: Twelve women with PCOS and 10 controls completed hyperinsulinaemic-euglycaemic clamps with randomised saline or lipid infusion, before and after 8 weeks of supervised exercise. Plasma metabolomics (163 metabolites) were measured at baseline, post-infusion and post-clamp. Linear mixed-effects models assessed Group × Timepoint × Intervention interactions. RESULTS: No baseline metabolite differences were observed between groups. A significant three-way interaction (p = 0.008) indicated condition-dependent trajectory divergence. Post hoc analysis revealed a specific divergence during post-exercise lipid challenge (p = 0.048). Women with PCOS showed reduced suppression of ether-linked phosphatidylcholines during insulin-stimulated lipid loading (PC ae C44:4, p = 0.031), despite exercise-induced improvements in fitness and normalisation of amino acid profiles. Exploratory metabolite ratios suggested impaired substrate coordination under stress. CONCLUSIONS: Metabolic defects in PCOS are stress-dependent and not detectable at rest. Exercise training improves resting metabolism but reveals persistent impairment in adaptive lipid handling during combined insulin and lipid challenges, suggesting impaired coordination of substrate supply during metabolic stress. TRIAL REGISTRATION: ClinicalTrials.gov identifier: ISRCTN42448814.

Humans↗