Isobavachalcone enhances sensitivity of colistin-resistant Klebsiella pneumoniae: in vitro and in vivo proof-of-concept studies.

Antibiotic resistance poses a considerable worldwide concern, particularly in clinical environments where drug-resistant Gram-negative bacteria like Klebsiella pneumoniae present a major challenge. The objective of this research was to investigate the mechanisms by which isobavachalcone (IBC) restores the sensitivity of K. pneumoniae to colistin in vitro and to validate the synergistic therapeutic effect in vivo. The results indicate that the combined administration of colistin and IBC exhibits a potent antibacterial effect both in vitro and in vivo. The in vitro concurrent administration of colistin and IBC resulted in increased membrane permeability, compromised cell integrity, diminished membrane fluidity, and disrupted membrane homeostasis. Additionally, this combination reduced biofilm production, inhibited the synthesis of the AI-2 factor, altered membrane potential, and affected levels of reactive oxygen species and adenosine triphosphate synthesis, ultimately leading to bacterial death. In vivo experiments on Galleria mellonella and mice demonstrated that the co-administration of colistin and IBC increased the survival rate and significantly reduced pathological damage compared to colistin alone. These results suggested that IBC effectively restores the sensitivity of colistin by inducing physical disruption of bacterial membranes and oxidative stress. The combination therapy of colistin and IBC presents a viable and safe strategy to combat drug-resistant K. pneumoniae-associated infections.

The Epstein-Barr virus small capsid protein BFRF3 disrupts the NF-кB signaling pathway by inhibiting p65 activity.

Epstein-Barr virus (EBV), a common gamma herpesvirus, establishes a life-long latent infection in the host to defend against innate immune recognition, which is closely related to a variety of malignant tumors, but its specific mechanism is unclear. BFRF3, an EBV-encoded small capsid protein, is mainly involved in the assembly of the viral capsid structure and the maintenance of its stability. Here, we showed that BFRF3 can inhibit TNF-α-mediated NF-кB promoter activation. Moreover, BFRF3 downregulates NF-кB-mediated promoter activation and transcription of inflammatory cytokines, including IL-6 and IL-8. Dual-luciferase reporter assay demonstrated that BFRF3 restrains NF-кB promoter activity at or below the p65 level, and coimmunoprecipitation analysis revealed that BFRF3 not only interacts with p65 but also binds to its critical truncated Rel homology domain (RHD) and transcriptional activation domain (TAD). However, BFRF3 does not affect the dimerization of p65-p50, but overexpression of BFRF3 reduces the nuclear accumulation of p65, and the phosphorylation of p65 (Ser536) is repressed during BFRF3 transfection and EBV lytic infection, which promotes the proliferation of EBV. Overall, our study suggested that BFRF3 may play a crucial role in antiviral immunity to defend against EBV infection by inhibiting NF-κB activity.

An attribution graph-based interpretable method for CNNs.

Convolutional Neural Networks (CNNs) have demonstrated outstanding performance in various domains, such as face recognition, object detection, and image segmentation. However, the lack of transparency and limited interpretability inherent in CNNs pose challenges in fields such as medical diagnosis, autonomous driving, finance, and military applications. Several studies have explored the interpretability of CNNs and proposed various post-hoc interpretable methods. The majority of these methods are feature-based, focusing on the influence of input variables on outputs. Few methods undertake the analysis of parameters in CNNs and their overall structure. To explore the structure of CNNs and intuitively comprehend the role of their internal parameters, we propose an Attribution Graph-based Interpretable method for CNNs (AGIC) which models the overall structure of CNNs as graphs and provides interpretability from global and local perspectives. The runtime parameters of CNNs and feature maps of each image sample are applied to construct attribution graphs (At-GCs), where the convolutional kernels are represented as nodes and the SHAP values between kernel outputs are assigned as edges. These At-GCs are then employed to pretrain a newly designed heterogeneous graph encoder based on Deep Graph Infomax (DGI). To comprehensively delve into the overall structure of CNNs, the pretrained encoder is used for two types of interpretable tasks: (1) a classifier is attached to the pretrained encoder for the classification of At-GCs, revealing the dependency of At-GC's topological characteristics on the image sample categories, and (2) a scoring aggregation (SA) network is constructed to assess the importance of each node in At-GCs, thus reflecting the relative importance of kernels in CNNs. The experimental results indicate that the topological characteristics of At-GC exhibit a dependency on the sample category used in its construction, which reveals that kernels in CNNs show distinct combined activation patterns for processing different image categories, meanwhile, the kernels that receive high scores from SA network are crucial for feature extraction, whereas low-scoring kernels can be pruned without affecting model performance, thereby enhancing the interpretability of CNNs.

Exploring the function and prognostic value of RPLP0, RPLP1 and RPLP2 expression in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the most common subtype of non-small cell lung cancer (NSCLC) and is characterized by its heterogeneity and poor prognosis. The role of ribosomal proteins RPLP0, RPLP1 and RPLP2 in multiple cancers has been implicated. However, their function in LUAD and their correlation with the poor prognosis of LUAD remains elusive. In this study, we performed a comprehensive bioinformatic analysis of the impact of these ribosomal proteins on LUAD. Our findings reveal that RPLP0, RPLP1 and RPLP2 are overexpressed in LUAD, which are likely attributed to abnormal copy number variations and decreased methylation levels of their promoters. LUAD patients with high expression of RPLP0, RPLP1 or RPLP2 have worse clinical outcomes in terms of overall survival (OS), first progression (FP) and post-progression survival (PPS), indicating poor prognosis. Moreover, the expression of RPLP0, RPLP1 and RPLP2 affects immune cell infiltration in LUAD tissues. Finally, we identified multiple existing drugs that may inhibit the expression of RPLP1 and RPLP2. Collectively, our data implicate the oncogenic role of RPLP0, RPLP1 and RPLP2 in LUAD and underscore their prognostic value in LUAD patients.

Research note: characteristics of blaNDM and mcr-1 co-producing Escherichia coli from retail chicken meat.

Carbapenems and colistin are vital antimicrobials used to treat Enterobacteriaceae-caused infections. The present study aimed to characterize the coexistence mechanism of carbapenem and colistin resistance in an Escherichia coli isolated from retail chicken meat. A total of 4 E. coli isolates co-harboring carbapenem resistance gene blaNDM (2 E. coli isolates with blaNDM-5 and 2 with blaNDM-9) and colistin resistance gene mcr-1. Antimicrobial susceptibility testing exhibited that all the 4 E. coli strains had multidrug resistance profile and consistent with the resistance genes they carried. MLST showed that 3 E. coli isolates belonged to a pathogenic E. coli lineage ST354, which is closely associated with human infections and pose a serious threat to public health. Whole genome sequencing (WGS) showed that 4 mcr-1-positive plasmids with sizes of 60.4 kb to 67.4 kb all belonged to the IncI2 type. A total of 5 blaNDM-harboring plasmids ranged from 99.0 kb to 138.3 kb, among which 4 plasmids belonged to unknow type and only pCS5L-NDM belonged to IncFIA/IncFIB group of hybrid plasmids, a novel carrier for blaNDM. Comparative analysis exhibited that the mcr-1 or blaNDM-carrying plasmids of E. coli strains from chicken meat showed high identity with that from Enterobacteriaceae of human origin, which indicated the risk of mcr-1 or blaNDM dissemination from retail meat to human. The simultaneous occurrence of mcr-1 and blaNDM in E. coli emphasizes the significant of antimicrobial resistance surveillance in retail meat.

Identification and validation of sialyltransferase ST3Gal5 in bladder cancer through bioinformatics and experimental analysis.

BACKGROUND: Bladder cancer (BLCA) is one of the top ten most common cancers in the world. Aberrant sialylation is a common feature in tumorigenesis and tumor immunity. This study seeks to explore the potential impact of sialyltransferase ST3Gal5 on BLCA. METHODS: Initially, glycosyltransferase-related DEGs (GRDEGs) were identified using multiple bioinformatics approaches in TCGA-BLCA cohort and validated using GEO databases. Clinical prognosis integration facilitated the determination of ST3Gal5 as an independent prognostic factor in BLCA, employing univariate and multivariate Cox regression analyses. Immune cell infiltration was assessed via CIBERSORT and ssGSEA analyses, while HLA and immune checkpoint genes' levels, along with drug sensitivity, were evaluated in low- and high-ST3Gal5 groups. The TIDE and IPS scores were used to gauge the immune checkpoint blockade (ICB) response. Furthermore, functional experiments, both in vivo and in vitro, were conducted to elucidate the biological roles of ST3Gal5. RESULTS: In agreement with bioinformatics findings, ST3Gal5 expression was down-regulated in BLCA tissues and cells, correlating with poorer prognostic outcomes. The StromalScore, ImmuneScore, and ESTIMATEScore were significantly elevated in low-ST3Gal5 group. Moreover, the levels of HLA and immune checkpoint genes were upregulated in low-ST3Gal5 group. Down-regulated ST3Gal5 promoted the proliferation, migration, and invasion of BLCA cells in vivo and in vitro. CONCLUSION: Our findings demonstrated that low ST3Gal5 level promoted tumorigenesis and progression of BLCA, implying its potential as a predictive biomarker and therapeutic target.

Structure characteristics and combustion kinetics of the co-pyrolytic char of rice straw and coal gangue.

Co-combustion is a technology that enables the simultaneous and efficient utilization of biomass and coal gangue (CG). Nevertheless, the factors that affect the combustibility of co-pyrolytic char, which represents the rate-determining step of the entire co-combustion process, remain unclear. This study investigates the impact of the physicochemical properties of co-pyrolytic char, including pore structure, carbon structure, and alkali metals, on the combustion characteristics. The TGA analysis indicates that the ignition and burnout temperatures of the co-pyrolytic char increase as the CG mixing ratio increases, resulting in a prolonged combustion. This is due to the fact that the carbon structure of the co-pyrolytic char becomes increasingly aromatic, accompanied by a reduction in aliphatic hydrocarbons and oxygen-containing groups as the CG mixing ratio increases. Furthermore, the high ash content of the CG is another significant factor contributing to the observed reduction in combustibility. The reaction between mullite, quartz in CG, and alkali metals in biomass results in the formation of aluminosilicate, which reduces the catalytic ability of alkali metals. Furthermore, the char combustion kinetics are analyzed by the KAS method, and the results indicate that the introduction of CG increases the activation energy of the entire char combustion process. The activation energy of the 80RS20CG is within the range of 102.22-164.99 kJ/mol, while the RS char is within the range of 89.87-144.67 kJ/mol.

Extracellular vesicles isolated from curcumin-medium weakened RKO cell proliferation and migration.

Background: Curcumin (Cur) is a natural phytochemical that is expected to become an indispensable drug for the treatment of colorectal cancer. A comprehensive understanding of the anti-tumor mechanism of Cur will provide a better reference for its clinical application. This study aimed to examine the effects of extracellular vesicles (EVs) isolated from Cur-medium on RKO colorectal cancer cell proliferation, apoptosis, and migration. Methods: RKO cells were cultured in various concentrations of Cur-medium, and the EVs were isolated from the Cur-medium. The EVs were identified by transmission electron microscopy and western blotting. The effects of the EVs on RKO cell proliferation, apoptosis, and migration were analyzed, as was the expression of proliferating cell nuclear antigen (PCNA), Bax, vimentin, and E-cadherin. The expression of nuclear factor κB (NF-κB) p65 in the EVs was also detected. Results: Our results showed that the EVs isolated from the Cur-medium weakened RKO cell proliferation and migration but had no effect on cell apoptosis. Cur suppressed the expression of NF-κB p65 in the EVs. Overall, this study revealed that Cur exerts anti-tumor effects by suppressing NF-κB p65 in EVs to weaken RKO cell proliferation and migration. Conclusions: In conclusion, the packaging of Cur into EVs is expected to become an indispensable treatment of colorectal cancer in the future.

Assessment of left ventricular ejection fraction in artificial intelligence based on left ventricular opacification.

Background: Left ventricular opacification (LVO) improves the accuracy of left ventricular ejection fraction (LVEF) by enhancing the visualization of the endocardium. Manual delineation of the endocardium by sonographers has observer variability. Artificial intelligence (AI) has the potential to improve the reproducibility of LVO to assess LVEF. Objectives: The aim was to develop an AI model and evaluate the feasibility and reproducibility of LVO in the assessment of LVEF. Methods: This retrospective study included 1305 echocardiography of 797 patients who had LVO at the Department of Ultrasound Medicine, Union Hospital, Huazhong University of Science and Technology from 2013 to 2021. The AI model was developed by 5-fold cross validation. The validation datasets included 50 patients prospectively collected in our center and 42 patients retrospectively collected in the external institution. To evaluate the differences between LV function determined by AI and sonographers, the median absolute error (MAE), spearman correlation coefficient, and intraclass correlation coefficient (ICC) were calculated. Results: In LVO, the MAE of LVEF between AI and manual measurements was 2.6% in the development cohort, 2.5% in the internal validation cohort, and 2.7% in the external validation cohort. Compared with two-dimensional echocardiography (2DE), the left ventricular (LV) volumes and LVEF of LVO measured by AI correlated significantly with manual measurements. AI model provided excellent reliability for the LV parameters of LVO (ICC > 0.95). Conclusions: AI-assisted LVO enables more accurate identification of the LV endocardium and reduces observer variability, providing a more reliable way for assessing LV function.

How COVID-19 Information Fear of Missing out Increases the Risk of Depression and Anxiety: Roles of Resilience and Personality Types.

During major health emergencies (e.g., the COVID-19 pandemic) people often fear missing relevant information. COVID-19 information fear of missing out (FOMO) is a phenomenon where people feel anxiety about losing control of COVID-19-related information. The present study aimed to examine how COVID-19 information FOMO relates to mental health (e.g., depression and anxiety), the mediating role of resilience, and the moderating role of personality types during the COVID-19 pandemic. We surveyed 1442 Chinese undergraduates (Mage = 21.68 ± 2.35 years) on the relevant variables. The results showed that COVID-19 information FOMO was positively associated with depression and anxiety, and resilience mediated these associations. Latent profile analysis (LPA) identified three personality types (undercontrolled, adaptive, and overcontrolled). Personality types moderated the mediation models, in which the indirect effects were only significant in the participants classified in the undercontrolled group rather than the participants classified in the other two groups. This study told us that undergraduates' mental health, particularly that of the undercontrollers, should be paid attention to when responding to a major public health emergency (e.g., the COVID-19 pandemic).

Tandem amplification of a plasmid-borne tet(A) variant gene confers tigecycline resistance in Escherichia coli.

OBJECTIVES: To elucidate the mechanism of tigecycline resistance in Escherichia coli that is mediated by the tet(A) variant gene. METHODS: E. coli strain 573 carried a plasmid-borne tet(A) variant gene, tentatively designated tet(A)TIG, that conferred decreased tigecycline susceptibility (MIC 0.5 mg/L). When exposed to increasing concentrations of tigecycline (0.25-8 mg/L), mutants growing at 2, 4 and 8 mg/L were obtained and sequenced. Copies of plasmid and tet(A)TIG relative to the chromosomal DNA in the mutants were determined by WGS and quantitative PCR (qPCR). Expression of tet(A)TIG in the mutants was evaluated by RT-qPCR. The tet(A)TIG-carrying plasmids were visualized by S1-PFGE and Southern blot hybridization. PCR served for the detection of a tet(A)TIG-carrying unconventional circularizable structure (UCS). RESULTS: Tigecycline resistance with maximum MICs of 16 mg/L was seen in E. coli mutants selected in the presence of tigecycline. Compared with the parental strain, the relative copy number and transcription level of tet(A)TIG in the mutants increased significantly in the presence of 2, 4 and 8 mg/L tigecycline, respectively. With increasing tigecycline selection pressure, the tet(A)TIG-carrying plasmids in the mutants increased in size, correlating with the number of tandem amplificates of a ΔTnAs1-flanked UCS harbouring tet(A)TIG. These tandem amplificates were not stable in the absence of tigecycline. CONCLUSIONS: Tigecycline resistance is due to the tandem amplification of a ΔTnAs1-flanked tet(A)TIG-carrying plasmid-borne segment in E. coli. The gain/loss of the tandem amplificates in the presence/absence of tigecycline represents an economic way for the bacteria to survive in the presence of tigecycline.

Thin-Film Composite Membrane Compaction: Exploring the Interplay among Support Compressive Modulus, Structural Characteristics, and Overall Transport Efficiency.

Water scarcity has driven the demand for water production from unconventional sources and the reuse of industrial wastewater. Pressure-driven membranes, notably thin-film composite (TFC) membranes, stand as energy-efficient alternatives to the water scarcity challenge and various wastewater treatments. While pressure drives solvent movement, it concurrently triggers membrane compaction and flux deterioration. This necessitates a profound comprehension of the intricate interplay among compressive modulus, structural properties, and transport efficacy amid the compaction process. In this study, we present an all-encompassing compaction model for TFC membranes, applying authentic structural and mechanical variables, achieved by coupling viscoelasticity with Monte Carlo flux calculations based on the resistance-in-series model. Through validation against experimental data for multiple commercial membranes, we evaluated the influence of diverse physical parameters. We find that support polymers with a higher compressive modulus (lower compliance), supports with higher densities of "finger-like" pores, and "sponge-like" pores with optimum void fractions will be preferred to mitigate compaction. More importantly, we uncover a trade-off correlation between steady-state permeability and the modulus for identical support polymers displaying varying porosities. This model holds the potential as a valuable guide in shaping the design and optimization for further TFC applications and extending its utility to biological scaffolds and hydrogels with thin-film coatings in tissue engineering.

Effect of Social Support on Career Decision-Making Difficulties: The Chain Mediating Roles of Psychological Capital and Career Decision-Making Self-Efficacy.

This present study explores the effect of social support on career decision-making difficulties, with the chain mediation of psychological capital and career decision-making self-efficacy. A total of 770 college students were recruited to complete the survey, which included a social support, career decision-making self-efficacy, psychological capital scale, and career decision-making difficulties scales. Significant correlations were found between social support, career decision-making difficulties, psychological capital, and career decision making self-efficacy. Path analysis indicated that the direct effect of social support on career decision-making difficulty was non-significant; social support affected career decision-making difficulties indirectly through not only the mediating effect of psychological capital but also through the chain mediation of psychological capital and career decision-making self-efficacy. Overall, the results show that social support could exert an effect on career decision-making difficulties through the mediational chains of career decision-making self-efficacy and psychological capital; the implications of this are discussed.

Associations of apolipoprotein E ε4 allele, regional cerebral blood flow, and serum liver function markers in patients with cognitive impairment.

Introduction: The ε4 allele of the apolipoprotein E gene (APOE4) is expressed abundantly in both the brain and peripheral circulation as a genetic risk factor for Alzheimer's disease (AD). Cerebral blood flow (CBF) dysfunction is an essential feature of AD, and the liver plays an important role in the pathogenesis of dementia. However, the associations of APOE4 with CBF and liver function markers in patients with cognitive impairment remains unclear. We aimed to evaluate the associations of APOE4 with CBF measured by arterial spin labeling (ASL) magnetic resonance imaging (MRI) and serum liver function markers in participants who were diagnosed with cognitive impairment. Methods: Fourteen participants with AD and sixteen with amnestic mild cognitive impairment (MCI) were recruited. In addition to providing comprehensive clinical information, all patients underwent laboratory tests and MRI. All participants were divided into carriers and noncarriers of the ε4 allele, and T-tests and Mann-Whitney U tests were used to observe the differences between APOE4 carriers and noncarriers in CBF and liver function markers. Results: Regarding regional cerebral blood flow (rCBF), APOE4 carriers showed hyperperfusion in the bilateral occipital cortex, bilateral thalamus, and left precuneus and hypoperfusion in the right lateral temporal cortex when compared with noncarriers. Regarding serum liver function markers, bilirubin levels (including total, direct, and indirect) were lower in APOE4 carriers than in noncarriers. Conclusion: APOE4 exerts a strong effect on CBF dysfunction by inheritance, representing a risk factor for AD. APOE4 may be related to bilirubin metabolism, potentially providing specific neural targets for the diagnosis and treatment of AD.

Associations of Serum Liver Function with Cerebral Blood Flow in Patients with Alzheimer's Disease.

Background: Increasing evidence suggests that both amyloid-ß metabolism disorders in the liver and cerebral hypoperfusion play an important role in the pathogenesis of Alzheimer's disease (AD). However, the relevance of liver function alterations to cerebral blood flow (CBF) of patients with AD remains unclear. Objective: We aimed to investigate the associations between liver function changes and CBF of patients with AD. Methods: We recruited 17 patients with sporadic AD. In addition to physical and neurological examinations, detection of AD biomarkers in cerebrospinal fluid by enzyme-linked immunosorbent assay and CBF assessment by arterial spin labeling sequence of magnetic resonance image scans as well as measure of liver function markers in serum by routine laboratory testing were conducted. Neuropsychological tests were evaluated, including Mini-Mental State Examination and Montreal Cognitive Assessment. Linear and rank correlations were performed to test the associations of liver function alterations with regional CBF of AD. Results: We found that liver function markers, especially total protein, the ratio of albumin to globin, globin, alkaline phosphatase, and aspartate aminotransferase were significantly associated with regional CBF of AD patients. Conclusions: These findings demonstrated significant associations between perfusion in certain brain regions of AD and alterations of liver function markers, particularly proteins and liver enzymes, which might provide implications to the pathogenesis and treatment of AD.

Effects of tumor necrosis factor-alpha inhibitors on lipid profiles in patients with psoriasis: a systematic review and meta-analysis.

Background: There is no consensus on the effect of tumor necrosis factor-alpha (TNF-alpha) inhibitors on lipid profiles in patients with psoriasis. This study aimed to investigate the effects of TNF-alpha inhibitors on lipid profiles (triglycerides, total cholesterol, low-density lipoprotein, or high-density lipoprotein) in patients with psoriasis. Methods: We searched PubMed, Embase, and Cochrane Library databases for articles published before October 17, 2023. Four TNF-alpha inhibitors (infliximab, etanercept, adalimumab, and certolizumab) were included in our study. (PROSPERO ID: CRD42023469703). Results: A total of twenty trials were included. Overall results revealed that TNF-alpha inhibitors elevated high-density lipoprotein levels in patients with psoriasis (WMD = 2.31; 95% CI: 0.96, 3.67; P = 0.001), which was supported by the results of sensitivity analyses excluding the effect of lipid-lowering drugs. Subgroup analyses indicated that high-density lipoprotein levels were significantly increased in the less than or equal to 3 months group (WMD = 2.88; 95% CI: 1.37, 4.4; P < 0.001), the etanercept group (WMD = 3.4; 95% CI = 1.71, 5.09, P < 0.001), and the psoriasis group (WMD = 2.52; 95% CI = 0.57, 4.48, P = 0.011). Triglyceride levels were significantly increased in the 3 to 6-month group (WMD = 4.98; 95% CI = 1.97, 7.99, P = 0.001) and significantly decreased in the 6-month and older group (WMD = -19.84; 95% CI = -23.97, -15.7, P < 0.001). Additionally, Triglyceride levels were significantly increased in the psoriasis group (WMD = 5.22; 95% CI = 2.23, 8.21, P = 0.001). Conclusion: Our results revealed that TNF-alpha inhibitors might temporarily increase high-density lipoprotein levels in patients with psoriasis. However, changes in triglycerides were not consistent among the different durations of treatment, with significant increases after 3 to 6 months of treatment. Future prospective trials with long-term follow-up contribute to confirming and extending our findings. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023469703.

Electrolyte Optimization Strategy: Enabling Stable and Eco-Friendly Zinc Adaptive Interfacial Layer in Zinc Ion Batteries.

Aqueous zinc ion batteries (AZIBs) have emerged as a promising battery technology due to their excellent safety, high capacity, low cost, and eco-friendliness. However, the cycle life of AZIBs is limited by severe side reactions and zinc dendrite growth on the zinc electrode surface, hindering large-scale application. Here, an electrolyte optimization strategy utilizing the simplest dipeptide glycylglycine (Gly-Gly) additive is first proposed. Theoretical calculations and spectral analysis revealed that, due to the strong interaction between the amino group and Zn atoms, Gly-Gly preferentially adsorbs on zinc's surface, constructing a stable and adaptive interfacial layer that inhibits zinc side reactions and dendrite growth. Furthermore, Gly-Gly can regulate zinc ion solvation, leading to a deposition mode shift from dendritic to lamellar and limiting two-dimensional dendrite diffusion. The symmetric cell with the addition of a 20 g/L Gly-Gly additive exhibits a cycle life of up to 1100 h. Under a high current density of 10 mA cm-2, a cycle life of 750 cycles further demonstrates the reliable adaptability of the interfacial layer. This work highlights the potential of Gly-Gly as a promising solution for improving the performance of AZIBs.

Molecular detection and genetic characteristics of Giardia duodenalis in dairy cattle from large-scale breeding farms in Xinjiang, China.

Giardia duodenalis is an intestinal protozoan that can infect both humans and animals, leading to public health issues and economic losses in the livestock industry. G. duodenalis has been reported to infect dairy cattle, but there is limited information available on large-scale dairy farms in Xinjiang, China. The study collected 749 fresh faecal samples from five large-scale cattle farms in Xinjiang, China. The study used a nested PCR assay of the small subunit ribosomal RNA (SSU rRNA*) gene to determine the presence of G. duodenalis. The results showed that 24.0% (180/749) of dairy cattle were positive for G. duodenalis, with the highest infection rate observed in pre-weaned calves (45.1%, 69/153). Among the 180 G. duodenalis positive samples, three assemblages were identified: assemblage E (n = 176), assemblage A (n = 3) and assemblage B (n = 1). Sixty-nine, 67 and 49 sequences were obtained for the beta-giardin (bg*) gene, the glutamate dehydrogenase (gdh*) gene and the triose phosphate isomerase (tpi*) gene, respectively. Thirteen novel sequences of assemblage E were identified, including five sequences from the bg* gene, four sequences from the gdh* gene and four sequences from the tpi* gene. This study found that 32 G. duodenalis assemblage E isolates formed 26 MLGs, indicating genetic variation and geographic isolation-based differentiation in bovine-derived G. duodenalis assemblage E. These findings provide fundamental insights into the genetic diversity of G. duodenalis in dairy cattle and can aid in the prevention and control of its occurrence in large-scale dairy cattle farms.