Innovative hierarchical porous hydrophilic molecularly imprinted resin for high-throughput detection of perfluorocarboxylic acids in milk using 96-well plate SPE-LC-MS/MS.

The accumulation of perfluorocarboxylic acids (PFCAs) in environment and foods represents a significant threat to public health due to the long-term ingestion of contaminated food. This study introduces a novel adsorbent, the hierarchical porous hydrophilic molecularly imprinted resin (HPHMIR), which was synthesized by integrating molecular imprinting techniques with hydrophilic resins. The HPHMIR, characterized by its extensive mesoporous structure (average pore width ∼9.71 nm) and favorable imprinting factors (2.6-5.0), facilitates the effective adsorption of PFCAs from complex matrices through multiple interaction mechanisms, including hydrogen bonding and electrostatic interactions. This innovative material was employed in a 96-well plate format for solid-phase extraction (SPE), and combined with LC-MS/MS, a high-throughput method for the determination of PFCAs in milk was developed. The proposed method demonstrated exceptional performance, including excellent linearity (0.48-240 ng mL-1; r ≥ 0.9986), low detection limits (0.04-0.11 ng mL-1), high precision (relative standard deviation ≤ 9.9 %), and satisfactory recovery (75.7-118.1 %). These results highlight the efficacy of the method in extracting trace levels of PFCAs from complicated sample matrices, presenting a promising alternative for monitoring PFCA contamination and advancing public health standards.

Health Co-Benefits of Environmental Changes in the Context of Carbon Peaking and Carbon Neutrality in China.

IMPORTANCE: Climate change mitigation policies aimed at limiting greenhouse gas (GHG) emissions would bring substantial health co-benefits by directly alleviating climate change or indirectly reducing air pollution. As one of the largest developing countries and GHG emitter globally, China's carbon-peaking and carbon neutrality goals would lead to substantial co-benefits on global environment and therefore on human health. This review summarized the key findings and gaps in studies on the impact of China's carbon mitigation strategies on human health. HIGHLIGHTS: There is a wide consensus that limiting the temperature rise well below 2 °C would markedly reduce the climate-related health impacts compared with high emission scenario, although heat-related mortalities, labor productivity reduction rates, and infectious disease morbidities would continue increasing over time as temperature rises. Further, hundreds of thousands of air pollutant-related mortalities (mainly due to PM2.5 and O3) could be avoided per year compared with the reference scenario without climate policy. Carbon reduction policies can also alleviate morbidities due to acute exposure to PM2.5. Further research with respect to morbidities attributed to nonoptimal temperature and air pollution, and health impacts attributed to precipitation and extreme weather events under current carbon policy in China or its equivalent in other developing countries is needed to improve our understanding of the disease burden in the coming decades. CONCLUSIONS: This review provides up-to-date evidence of potential health co-benefits under Chinese carbon policies and highlights the importance of considering these co-benefits into future climate policy development in both China and other nations endeavoring carbon reductions.

Integrated Network Pharmacology and Molecular Docking to Explore the Mechanisms of Ningshen Wendan Decoction in the Treatment of Schizophrenia.

Objective: Schizophrenia (SCZ) is a prevalent chronic mental disorder characterized by a high recurrence rate and significant disability. Currently, no satisfactory pharmacological treatments have been identified. Although Ningshen Wendan decoction (NSWDD) has shown promising results in improving cognitive function in patients with schizophrenia, its underlying mechanism of action remains unclear. Methods: This study systematically investigated the mechanisms of NSWDD in SCZ treatment using network pharmacology and molecular docking approaches. Results: Analysis of the interaction genes revealed 307 common targets of NSWDD and SCZ. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated the involvement of multiple signaling pathways including interleukin 17 signaling pathway, multiple virus infections, Advanced glycosylation end products (AGEs) - receptor of AGEs (AGEs-RAGE) signaling pathway, tumor necrosis factor signaling pathway, and Hypoxia-inducible factor-1 (HIF-1) signaling pathway as key pathways influenced by NSWDD in treating SCZ. These pathways are associated with various biological processes such as transcriptional regulation, apoptosis regulation, gene expression regulation, and external stimulus-response. Molecular docking simulations indicated favorable binding interactions between components of NSWDD and target proteins via intermolecular forces. Conclusion: The study provided initial insights into the internal molecular mechanisms underlying the beneficial effect of NSWDD on SCZ through multi-target modulation across multiple pathways.

Advancing Lung Cancer Diagnosis through NH2-MON-SPME-GC-MS/MS: Enhanced Sensitivity in Aldehyde Biomarker Detection from Exhaled Breath.

The sensitive detection of trace biomarkers in exhaled breath for lung cancer diagnosis represents a critical area of research in life analytical chemistry, with profound implications for early disease detection, therapeutic intervention, and prognosis monitoring. Despite its potential, the analytical process faces significant challenges due to the ultratrace levels of disease biomarkers present and the complex, high-humidity composition of exhaled breath. This study introduces a highly sensitive method for detecting aldehyde biomarkers in exhaled breath by integrating the use of amino-functionalized microporous organic networks (NH2-MON) as a solid-phase microextraction (SPME) fiber coating with gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) analysis. The method innovatively combines sample collection and extraction, achieving a dual-step enrichment process that significantly enhances both the enrichment efficiency and reproducibility of biomarker detection while effectively mitigating the interference caused by water vapor in exhaled breath. The NH2-MON, utilized as an SPME fiber coating, demonstrates exceptional enrichment capacity for five key aldehyde biomarkers, facilitating the development of a highly sensitive detection approach for these biomarkers in exhaled breath. Compared to previously reported methods, the proposed technique exhibits significantly lower limits of quantification, ranging from 0.77 to 11.89 pg mL-1, and achieves substantially higher enrichment factors, ranging from 9156- to 35723-fold. The practicality and feasibility of the method were validated through the analysis of exhaled breath samples from lung cancer patients, underscoring its potential application in the early diagnosis and monitoring of lung cancer.

Structures of the Mycobacterium tuberculosis efflux pump EfpA reveal the mechanisms of transport and inhibition.

As the first identified multidrug efflux pump in Mycobacterium tuberculosis (Mtb), EfpA is an essential protein and promising drug target. However, the functional and inhibitory mechanisms of EfpA are poorly understood. Here we report cryo-EM structures of EfpA in outward-open conformation, either bound to three endogenous lipids or the inhibitor BRD-8000.3. Three lipids inside EfpA span from the inner leaflet to the outer leaflet of the membrane. BRD-8000.3 occupies one lipid site at the level of inner membrane leaflet, competitively inhibiting lipid binding. EfpA resembles the related lysophospholipid transporter MFSD2A in both overall structure and lipid binding sites and may function as a lipid flippase. Combining AlphaFold-predicted EfpA structure, which is inward-open, we propose a complete conformational transition cycle for EfpA. Together, our results provide a structural and mechanistic foundation to comprehend EfpA function and develop EfpA-targeting anti-TB drugs.

New insight into synergistic interaction between the backbone or side chain of xanthan gum and the backbone of Gleditsia sinensis polysaccharide.

In this study, the synergistic effect and weak gel mechanism of XG and Gleditsia sinensis polysaccharide (GSP) in different ratios were studied through the rheological properties, microstructure and molecular simulation based on density functional theory (DFT). The results of rheological properties showed that the mixtures formed a weak gel at the concentration of 0.5 % (w/v), with the synergistic impact peaking at a XG/GSP ratio of 3:7. Weak gels produced by XG and GSP had the intersection of G' and G" within the temperature sweep range, and the largest change in the G' slope at a XG/GSP ratio of 3:7. By calculating the interaction energy, it was found that the backbone of XG was more likely to interact with the backbone of GSP. Furthermore, the XG mainchain intersected with the backbone of GSP in a cross shape ("X" shape). As a result, this paper proposed a possible mechanism for the formation of the XG/GSP weak gel, with XG as the main chain and GSP as the grid point, and the main interaction type being hydrogen bonding, with the van der Waals force also involved. The results provide new insight for designing and producing physical gels with specific interactions in food industry.

Lower regional urbanicity and socioeconomic status attenuate associations of green spaces with hypertension and diabetes mellitus: a national representative cross-sectional study in China.

BACKGROUND: High blood pressure (HBP) and diabetes mellitus (DM) are two of the most prevalent cardiometabolic disorders globally, especially among individuals with lower socio-economic status (SES). Studies have linked residential greenness to decreased risks of HBP and DM. However, there has been limited evidence on whether SES may modify the associations of residential greenness with HBP and DM. METHODS: Based on a national representative cross-sectional study among 44,876 adults, we generated the normalized difference vegetation index (NDVI) at 1 km spatial resolution to characterize individuals' residential greenness level. Administrative classification (urban/rural), nighttime light index (NLI), individual income, and educational levels were used to characterize regional urbanicity and individual SES levels. RESULTS: We observed weaker inverse associations of NDVI with HBP and DM in rural regions compared to urban regions. For instance, along with per interquartile range (IQR, 0.26) increment in residential NDVI at 0∼5 year moving averages, the ORs of HBP were 1.04 (95%CI: 0.94, 1.15) in rural regions and 0.85 (95%CI: 0.79, 0.93) in urban regions (P = 0.003). Along with the decrease in NLI levels, there were continuously decreasing inverse associations of NDVI with DM prevalence (P for interaction <0.001). In addition, weaker inverse associations of residential NDVI with HBP and DM prevalence were found among individuals with lower income and lower education levels compared to their counterparts. CONCLUSIONS: Lower regional urbanicity and individual SES could attenuate the associations of residential greenness with odds of HBP and DM prevalence.

Studies on the characteristics of polycyclic aromatic hydrocarbons accumulation in lipids and the disturbance of lipid metabolism of Ruditapes philippinarum.

Polycyclic aromatic hydrocarbons (PAHs) constitute a class of persistent organic pollutants with strong lipophilicity, which readily accumulate within organisms and have the effect to induce disorders in lipid metabolism. The present study aimed to investigate the accumulation localization and pattern of PAHs in Ruditapes philippinarum, and to reveal the association between PAHs and lipids metabolism. The 21-day exposure experiment was conducted using a mixture of phenanthrene, chrysene, and benzo[a]pyrene (the proportion is 1:1:1) at concentrations of 0.4 µg/L, 2 µg/L, and 10 µg/L. The tissue distribution of PAHs indicated that the digestive gland was the primary site of PAHs accumulation. Meanwhile, fluorescence colocalization suggested that PAHs primarily accumulated within the lipid droplets of digestive gland cells. This study further determined the transcriptomic and lipidomic profiles of the digestive gland to analyze the key genes involved in disrupted lipid metabolism and the major lipids affected. Lipidomic analysis identified the key differential metabolites as triglycerides (TGs). Furthermore, TGs were upregulated in the digestive gland had a total carbon atom number of 50-64 and a total number of 3-9 double bonds in the acyl side chains. Biochemical analysis experiments and oil red O stained frozen sections confirmed that the content of TGs steadily increased in various tissues during the experiment, leading to an elevated digestive gland index. Changes of lipid metabolism associated genes expression level also indicated that the synthesis of lipid in digestive gland were up-regulated while the decomposition was down-regulated. This study is the first to demonstrate the cellular localization of PAHs accumulation in bivalves and confirms the pattern of variation in TGs, providing new insights into the mechanisms of PAHs bioaccumulation and lipid metabolism disruption.

A Medical Decision Support Platform for Identifying Thrombospondin 1 in Non-alcoholic Fatty Liver Disease via Immuno-Infiltration Analysis.

Non-alcoholic fatty liver disease (NAFLD) and myocardial infarction (MI) are two major health burdens with significant prevalence and mortality. This study aimed to explore the co-expressed genes to understand the relationship between NAFLD and MI and identify potential crucial biomarkers of NAFLD-related MI using bioinformatics and machine learning. Functional enrichment analysis was conducted, a co-protein-protein interaction (PPI) network diagram was constructed, and support vector machine-recursive feature elimination (SVM-RFE) and least absolute shrinkage and selection operator (LASSO) techniques were employed to identify one differentially expressed gene (DEG), Thrombospondin 1 (THBS1). THBS1 demonstrated strong performance in distinguishing NAFLD patients (AUC = 0.981) and MI patients (AUC = 0.900). Immuno-infiltration analysis revealed significantly lower CD8+ T cells and higher neutrophil levels in patients with NAFLD and MI. CD8+ T cells and neutrophils were effective in distinguishing NAFLD/MI from healthy controls. Correlation analysis showed that THBS1 was positively correlated with CCR (chemokine receptor), MHC class (major histocompatibility complex class), neutrophils, parainflammation, and Tfh (follicular helper T cells), and negatively correlated with CD8+ T cells, cytolytic activity, and TIL (tumor-infiltrating lymphocytes) in NAFLD and MI patients. THBS1 emerged as a novel biomarker for diagnosing NAFLD/MI in comparison to healthy controls. The results indicate that CD8+ T cells and neutrophils could serve as inflammatory immune features for differentiating patients with NAFLD/MI from healthy individuals.

Compensation Techniques for Photosensors Used in High-Precision Accelerometers.

Temperature exerts a profound influence on the fidelity of photosensors, making the attainment of reliable temperature compensation a formidable task within engineering realms. This research delves into the intricacies of photosensors used in high-precision accelerometers, proposing an innovative, high-precision, adaptive, closed-loop compensation mechanism. Our design stands in stark contrast to traditional open-loop models, demonstrating superior performance by achieving a remarkable reduction in compensation error-nearly 98%. This advancement in consistency and precision marks a significant leap forward for the application of high-precision photosensors in engineering contexts.

Preparation and Stability Study of an Injectable Hydrogel for Artificial Intraocular Lenses.

Currently available intraocular lenses (IOLs) on the market often differ significantly in elastic modulus compared to the natural human lens, which impairs their ability to respond effectively to the tension of the ciliary muscles for focal adjustment after implantation. In this study, we synthesized a polyacrylamide-sodium acrylate hydrogel (PAH) through the cross-linking polymerization of acrylamide and sodium acrylate. This hydrogel possesses excellent biocompatibility and exhibits several favorable properties. Notably, the hydrogel demonstrates high transparency (94%) and a refractive index (1.41 ± 0.07) that closely matches that of the human lens (1.42). Additionally, it shows strong compressive strength (14.00 kPa), good extensibility (1400%), and an appropriate swelling ratio (50 ± 2.5%). Crucially, the tensile modulus of the hydrogel is 2.07 kPa, which closely aligns with the elastic modulus of the human lens (1.70-2.10 kPa), enabling continuous focal adjustment under the tension exerted by the ciliary muscles.

Exploring Ion Polarizabilities and Their Correlation with van der Waals Radii: A Theoretical Investigation.

Polarizability (α) is a fundamental property which measures the tendency of the electron cloud of an atom, ion, or molecule to be distorted by electric field. Polarizability contributes to important physical properties such as molecular interactions or dielectric constants; thus, it is essential to have accurate polarizabilities in molecular simulations. However, it remains a challenge to develop polarizable force fields (FFs) for ions in computational chemistry. In particular, a comprehensive set of polarizabilities for ions has not been derived. Herein, we derived a systematic set of polarizabilities for atoms and ions across the periodic table based on high-level quantum mechanics calculations. These values have excellent agreement with experimental data. Furthermore, we examined the relationship between the obtained polarizabilities and the van der Waals (VDW) radii (RVDW) that we previously determined (J. Chem. Theory Comput., 2023, 19, 2064). Two relationships, RVDW ∝ α1/7 and RVDW ∝ α1/3, proposed in previous studies were examined in the present work. Our results indicated the former relationship, which was derived based on the quantum harmonic oscillator model, prevails for atoms and cations, but neither relationship provides a satisfactory fit for anions. This is consistent with the tight-binding nature of the electrons in atoms and cations, while it is more challenging to quantify the polarizabilities of anions because of their more dispersed electron clouds. Moreover, we compared different approaches to determine the dispersion coefficients, including the London equation, Slater-Kirkwood equation, symmetry-adapted perturbation theory (SAPT) calculations, and time-dependent density functional theory method, along with the approach based on VDW constants. Our results indicated that although different approaches predict deviated magnitudes for the dispersion coefficients, their predictions are highly correlated, implying that each of these approaches can be used to evaluate dispersion interactions after proper scaling. Finally, we have developed a parametrization strategy for the 12-6-4 model based on the obtained insights. We specifically compared the performance of the 12-6-4 model with SAPT and SobEDA analyses to model interactions involving Na+/Mg2+ and various ligands containing He, Ne, Ar, H2O, NH3, [H2PO4]-, and [HPO4]2-. Our results demonstrate that the 12-6-4 parameters effectively reproduce both the total interaction energy and the individual energy components (electrostatics, exchange-repulsion, dispersion, and induction), highlighting the physical robustness of the 12-6-4 model and the effectiveness of our parametrization approach. This study has significant implications for advancing the development of next-generation ion models and polarizable FFs.

Ultrastrong Nanopapers with Aramid Nanofibers and Silver Nanowires Reinforced by Cellulose Nanofibril-Assisted Dispersed Graphene Nanoplates for Superior Electromagnetic Interference Shielding.

High-strength, lightweight, ultrathin, and flexible electromagnetic interference (EMI) shielding materials with a high shielding effectiveness (SE) are essential for modern integrated electronics. Herein, cellulose nanofibrils (CNFs) are employed to homogeneously disperse graphene nanoplates (GNPs) into an aramid nanofiber (ANF) network and silver nanowire (AgNW) network, respectively, producing high-performance nanopapers. These nanopapers, featuring nacre-mimetic microstructures and layered architectures, exhibited high tensile strength (601.11 MPa) and good toughness (103.56 MJ m-3) with a thickness of only 24.58 µm. Their specific tensile strength reaches 447.59 MPa·g-1·cm3, which is 1.74 times that of titanium alloys (257 MPa·g-1·cm3). The AgNW/GNP composite conductive layers exhibit an electrical conductivity of 12010.00 S cm-1, providing the nanopapers with great EMI shielding performance, achieving an EMI SE of 63.87 dB and an EMI SE/t of 25978.80 dB cm-1. The nanopapers also show reliable durability, retaining a tensile strength of 500.96 MPa and an EMI SE of 57.59 dB after 120,000 folding cycles. Additionally, they have a good electrical heating performance with a fast response time, low driving voltage, effective deicing capability, and reliable heating capacity in water. This work presents a strategy to develop a high-performance nanopaper, showing great potential for applications in electromagnetic compatibility, national defense, smart electronics, and human health.

Regulation of autophagy by ST3GAL2-mediated α2-3 sialylated glycosphingolipids in hepatic encephalopathy.

In neurological diseases, the regulation of autophagy plays a crucial role in their pathology, particularly the relationship between autophagy and hepatic encephalopathy (HE) which merits detailed investigation. Glycosphingolipids are abundant and broadly functional in the nervous system and are closely associated with autophagy. However, the specific link and mechanisms between glycosphingolipids and autophagy in HE remain unclear. This study aims to explore the impact of glycosphingolipid changes on the autophagy in HE and its potential mechanisms. Utilizing lectin microarrays, we observed elevated expression levels of α2-3 sialylated glycosphingolipid in the brain tissue of HBV transgenic mice and ammonia-induced astrocyte models, suggesting that the increase in α2-3 sialylated glycosphingolipid is related to HE. Further research revealed that the increased expression of α2-3 sialylated glycosphingolipid, mediated by ST3GAL2, affects autophagy by regulating the autophagy initiation complex Vps34-Beclin-1. In summary, our research not only comprehensively reveals the changes in brain glycosphingolipid during HBV-related HE but also elucidates the interactions and regulatory mechanisms between α2-3 sialylated glycosphingolipid and autophagy. This study provides a new perspective on understanding the pathogenesis of HE and offers novel theories and targets for future research and treatment strategies.

Comparative long-term outcomes of unicompartmental and total knee arthroplasty in knee osteoarthritis patients: a systematic review and meta-analysis.

Background: Long-term outcomes for knee osteoarthritis patients undergoing unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) remain inconclusive. Objectives: This study aims to evaluate the long-term outcomes over five years, including Knee Society Pain Scores (KSPS), Knee Society Scores (KSS), Knee Society Function Scores (KSFS), range of motion (ROM), and survival rates-of UKA vs. TKA in knee osteoarthritis patients. Design: Systematic review using data from randomized controlled and cohort trials, and world databases. Data sources: Researchers searched Medline, Embase, Cochrane Controlled Register of Trials, and ClinicalTrials.gov from January 1990 to March 2024. Eligibility criteria for selecting studies: The researchers selected studies based on adult participants with knee osteoarthritis. Eligible studies compare UKA and TKA reports on clinical or surgical outcomes, including KSPS, KSS, KSFS, ROM and survival rates, over 5 years. The researchers excluded the studies fewer than five years, or if English text was unavailable. Results: Researchers categorized twenty-nine eligible studies into three groups: five randomized controlled trials, 11 registries and database studies, and 13 cohort studies. The analysis revealed that neither TKA nor UKA definitively outperformed the other in terms of pain (SMD (95% CI): -0.06 [-0.41, 0.28], I 2 = 90%) and KSS scores (SMD (95% CI): -0.07 [-0.23, 0.008], I 2 = 81%) over a period of five years. However, KSFS (SMD (95% CI): -0.30 [-0.43, -0.17], I 2 = 74%) and ROM (SMD (95% CI): -0.78 [-1.11, -0.46], I 2 = 92%) tended to favor UKA, and survival rate favor TKA at 5 or over 5-year follow-up periods. Conclusions: UKA shows a trend towards better outcomes in KSFS and ROM, alongside a more favorable survival rate in TKA at the five-year and beyond follow-up periods. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=517835, PROSPERO (CRD42024517835).

Nickel-Catalyzed Secondary Benzylic C-O Bond Borylation.

A remote steric hindrance ligand (m-tBu)2C6H3PCy2 (L1) was synthesized to promote Ni-catalyzed C-O bond activation. The reaction achieved high yields for secondary benzylic C(sp3)-O borylation in non-π-extended systems under mild conditions. Mechanistic studies indicate that the nickel complex containing 1 equiv of L1 serves as the active catalyst, while increased loading of L1 gives the inactive bisligated Ni species. Acetanilide is crucial for the cross-coupling reaction, which facilitates generation of the monoligated nickel species.

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Accurate assessment of material and energy exchange between land and atmosphere is essential for water resources management and sustainable development of agriculture. To understand the characteristics of energy distribution and the dynamic change process of water and heat fluxes within the maize farmland ecosystem in the old course of Yellow River and their response to meteorological factors, we utilized the eddy covariance measurements and the full-element automatic weather station to continuously observe energy fluxes and conventional meteorological elements of summer maize farmland in the old course of Yellow River during 2019-2020. We analyzed the variation of energy fluxes and the effects of environmental factors, such as temperature, precipitation, and wind speed. Additionally, we calculated the energy closure rate and the proportion of energy distribution during the growth stage. The results showed that the peaks of net radiation, sensible heat flux, and latent heat flux occurred between 11:00 and 14:00, and the peak of soil heat flux occurred between 14:00 and 15:00. In terms of energy distribution, energy consumption of summer maize farmland during the whole growth period was dominated by latent heat flux and sensible heat flux. Energy was mainly consumed by sensible heat flux at sowing-emergence stage, accounting for 37.1% of net radiation, respectively. Energy in the rest of growth stages was dominated by latent heat flux. The energy closure rate during the whole growth period was better, with a coefficient of determination of 0.83, and the closure rate was higher in day and lower at night. Precipitation affected latent heat flux and sensible heat flux, and latent heat flux was more sensitive to precipitation. The increase of latent heat flux after rainfall was lower in late growth stage than in early growth stage. During the whole growth period of summer maize, solar radiation was the most significant meteorological factor affecting both sensible heat flux and latent heat flux, followed by vapor pressure deficit. The contribution of temperature and vapor pressure deficit to latent heat flux was significantly higher than sensible heat flux, while the relative contribution of wind speed, relative humidity, and solar radiation to latent heat flux was lower than sensible heat flux. Leaf area index and fractional vegetation cover had a significant positive correlation with latent heat flux and a significant negative correlation with sensible heat flux. Our results could deepen the understanding of water and heat transfer law of summer maize farmland in the old course of Yellow River, providing a theoretical basis for efficient water use of crops.

A ribonuclease T2 protein FocRnt2 contributes to the virulence of Fusarium oxysporum f. sp. cubense tropical race 4.

Banana Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), is a major disease of banana plants worldwide. Effector proteins play critical roles in banana-Foc TR4 interaction. Our previous studies highlighted a ribonuclease protein belonging to the T2 family (named as FocRnt2) in the Foc TR4 secretome, which was predicted to be an effector. However, its biological function in Foc TR4 infection is still unclear. Herein, we observed significant expression of FocRnt2 during the early stage of fungal infection in planta. A yeast signal sequence trap assay showed that FocRnt2 contained a functional signal peptide for secretion. FocRnt2 possessed ribonuclease activity that could degrade the banana total RNA in vitro. Subcellular localization showed that FocRnt2 was localized in the nucleus and cytoplasm of Nicotiana benthamiana leaves. Transient expression of FocRnt2 suppressed the expression of salicylic acid- and jasmonic acid-signalling marker genes, reactive oxygen species accumulation, and BAX-mediated cell death in N. benthamiana. FocRnt2 deletion limited fungal penetration, reduced fusaric acid biosynthesis in Foc TR4, and attenuated fungal virulence against banana plants, but had little effect on Foc TR4 growth and sensitivity to various stresses. Furthermore, FocRnt2 deletion mutants induced higher expression of the defence-related genes in banana plants. These results suggest that FocRnt2 plays an important role in full virulence of Foc TR4, further improving our understanding of effector-mediated Foc TR4 pathogenesis.