Multidrug-resistant bacteria (MDRB) result in nosocomial infections and a substantial disease burden for hospitalised patients worldwide. However, strategies to control drug resistance at the hospital level are lacking. In this study, we aimed to find important indicators for risk assessment and predicting MDRB infections in the hospital. Using real-world data and machine learning models, we conducted a retrospective study from 2010 to 2020 in a teaching hospital to analyse the trends and characteristics of MDRB infections. Combining 39 hospital indicators, we used a random forest model and cross-correlation analysis to explore the important factors affecting MDRB and their predictive power. We built a decision tree model to predict the number of hospitalised patients with MDRB infection. The number of hospitalised rescues and rate of rational perioperative antibacterial drug use in type I and II incision operations were correlated with the number of patients with MDRB infection after 1-2 months. The number of hospitalised operations and rate of antibiotics use in emergency patients had an effect on current MDRB-susceptible patients. The indicators, including hospital operation volume and antibacterial drug use, had a positive or negative quantitative relationship with the number of patients with MDRB infection, and their thresholds could be fit to the MDRB prediction model. Surgical, emergency, and hospitalised rescue patients showed the highest risk of MDRB infection. Standardised indicators such as clinical pathway rate and rational antibiotic use rate could be used to control the development and spread of MDRB infections in the hospital.

Vaccination is one of the best ways to control the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic. Among the various SARS-CoV-2 vaccines approved for use, the BBIBP-CorV inactivated vaccine has been widely used in 93 countries. In order to understand deeply the protective mechanism of inactivated vaccine, which retains all antigenic components of live virus, the analysis of humoral responses triggered by multiple proteins is necessary. In this research, antibody responses were generated with 6 selected recombinant proteins and 68 overlapping peptides that completely covered SARS-CoV-2 nucleocapsid (N) protein in 254 healthy volunteers vaccinated with BBIBP-CorV. As a result, antibody responses to the receptor binding domain (RBD), N, and non-structural protein 8 (NSP8) were induced following immunization by BBIBP-CorV. The antibody responses detected in donors after the 2^nd dose vaccination can be maintained for about 6 months. Moreover, specific antibody levels can be restored after the boosting vaccination measured by ELISA. Furthermore, the level of SARS-CoV-2 specific IgG response is independent of age and gender. Moreover, N_391-408 was identified as a dominant peptide after vaccination of BBIBP-CorV through peptide screening. Understanding the overview of humoral reactivity of the vaccine will contribute to further research on the protective mechanism of the SARS-CoV-2 inactivated vaccine and provide potential biomarkers for the related application of inactivated vaccine.

Background: Human norovirus (HuNoV) is the leading cause of acute nonbacterial gastroenteritis globally, and its infection is usually self-limited, so most people become past Norovirus (NoV)-infected individuals. It is known that some antibody responses may play a critical role in preventing viral infection and alleviating disease; however, the characteristics and functions of particular antibody responses in persons with previous infections are not fully understood. Capsid proteins, including VP1 and VP2, are crucial antigenic components of NoV and may regulate antibody immune responses, while epitope-specific antibody responses to capsid proteins have not been comprehensively characterized. Methods: We prepared purified VP1 and VP2 proteins by ion exchange chromatography and measured serum antigen-specific IgG levels in 398 individuals by ELISA. Overlapping 18-mer peptides covering the full length of VP1 and VP2 were synthesized, and then we identified linear antigenic epitopes from 20 subjects with strong IgG positivity. Subsequently, specific antibody responses to these epitopes were validated in 185 past infected individuals, and the conservation of epitopes was analyzed. Finally, we obtained epitope-specific antiserum by immunizing mice and expressed virus-like particles (VLPs) in an insect expression system for a blockade antibody assay to evaluate the receptor-blocking ability of epitope-specific antibodies. Results: The IgG responses of VP1 were significantly stronger than those of VP2, both of which had high positive rates of over 80%. The overall positive rate of VP1-IgG and/or VP2-IgG was approximately 94%, which may be past NoV-infected individuals. Four linear antigenic B-cell epitopes of capsid proteins were identified, namely, VP1_199–216, VP1_469–492, VP2_97–120, and VP2_241–264, all of which were conserved. The IgG response rates of the above epitopes in past NoV-infected individuals were 38.92%, 22.16%, 8.11% and 28.11%, respectively. In addition, VP1_199–216- and VP1_469–492-specific antibodies can partially block the binding of VLPs to the receptor histo-blood group antigen (HBGA). Conclusion: This is the first study to describe specific antibody responses of VP2 and to identify its B-cell epitopes. Our findings offer data for a more thorough understanding of norovirus capsid protein-specific IgG responses and could provide useful information for designing and developing vaccines.

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants highlights the importance of monitoring immune responses to guide vaccination strategies. Although neutralizing antibodies (NAbs) have garnered increasing attention, T-cells are crucial for conferring long-lasting immunity, especially their resilience against viral mutations. However, assessing T-cell responses clinically has been hindered by cost and complexity. In this study, we recruited a cohort of 134 healthy adults, who had been immunized with three doses of the SARS-CoV-2 inactivated vaccine. Cellular immunity elicited by a comprehensive array of overlapping peptides covering the entire sequence of the virus's structural proteins was assessed by intracellular cytokine staining (ICS). Additionally, a dataset including demographic information, routine blood indices, and immune cell indicators comprising 32 variables was collected. Multivariate analysis revealed age and days post-vaccination as key factors influencing the strength of the T-cell response. Importantly, random forest (RF) and classification and regression tree (CART) algorithms were employed, along with 8 easily accessible indicators to formulate predictive models for the SARS-CoV-2-specific CD4⁺ and CD8⁺ T-cell responses. Besides, these models demonstrated substantial accuracy (r > 0.9) in both the training and testing sets. Our findings offer an efficient and economical methodology for evaluating the T-cell reactions in healthy adults following inactivated SARS-CoV-2 vaccination, which is visualizable and easy to use, providing a novel strategy for assessing cellular immunity after vaccination.

Introduction: Nasopharyngeal carcinoma (NPC), one of the most common malignancies of the head and neck, is characterised by a complex pathogenesis and an unfavourable prognosis. Recently, disulfidoptosis, a novel form of cell death, has been proposed. Several studies in recent years have extensively investigated the function of the disulfidoptosis-related SLC7A11 gene in cancer, but the role of its partner protein, SLC3A2, remains unknown unclear in NPC.Methods: GEO database analysis confirmed SLC3A2's prognostic impact on nasopharyngeal carcinoma. ROC, Kaplan-Meier analyses, and stage-specific expression studies showed a strong correlation with poor HNSC prognosis. GO and KEGG analyses pinpointed relevant signaling pathways. In vitro, SLC3A2's influence on cell proliferation, migration, and invasion was evaluated through CCK8, wound healing, colony formation, transwell assays, and cell cycle analysis.Results: In this study, we identified the high expression of SLC3A2 in NPC and head and neck squamous cell carcinoma (HNSC) and analyzed its potential mechanism and correlation with patient prognosis. Furthermore, a negative relationship was found between the expression level of SLC3A2 and the extent of immune cell infiltration and immune checkpoint. Differentially expressed genes (DEGs) between the high and low SLC3A2 expression groups were primarily involved in cytokine-cytokine receptor interaction and immune response. Finally, in vitro experiments demonstrated that SLC3A2 stimulates tumor cell proliferation and migration. Discussion: In conclusion, these results indicated a strong association between SLC3A2 and progression in both NPC and HNSC, suggesting it as a promising biomarker for predicting adverse prognosis in NPC and HNSC patients.

Background: Heteroresistance (HR) to commonly used anti-pseudomonal agents in Pseudomonas aeruginosa has been reported in cross-sectional epidemiological surveys; however, longitudinal studies investigating the long-term epidemiological dynamics and clinical correlates of this adaptive phenotype are still lacking. This retrospective time-series study aims to systematically explore the HR phenotypic profiles and temporal dynamic of clinical P. aeruginosa isolates against piperacillin/tazobactam (TZP) and meropenem (MEM), and further clarify their potential clinical correlates. Methods: We comprehensively analyzed 380 non-duplicate clinical strains collected from a tertiary hospital between 2011 and 2024. The disk diffusion and Etest gradient diffusion methods were used for the preliminary determination of HR incidence rates in clinical isolates against six anti-pseudomonal antibiotics. Population analysis profiling (PAP) assays was further performed to assess the temporal dynamics and phenotypic characteristics of HR to TZP MEM. HR was defined as the presence of resistant subpopulations with an MIC at least eightfold higher than that of the dominant population at a frequency of ≥ 1 × 10⁻⁷. Subsequently, univariate and multivariate regression analyses were performed to identify clinical factors associated with HR and non-HR strains. Results: Preliminary screening indicated that 55% of the tested strains exhibited the HR phenotype, whereas confirmatory assays further verified that 49.5% of the isolates displayed HR to either TZP or MEM. The HR detection rate for MEM peaked at 35.3% during 2017–2019, followed by a gradual decline, reaching a minimum of 24.04% during the 2020–2022 pandemic. Meanwhile, the HR rate to TZP initially increased, then decreased, peaking at 43.1% during 2017–2019 and subsequently declining to 27.8%. In addition, multivariate regression analysis identified that male gender and prior antiviral exposure were independently associated with decreased risk of HR, whereas prior fluoroquinolone antibiotics exposure was independently associated with an increased risk. Conclusion: Our findings highlight the widespread prevalence, distinct temporal dynamics, and diverse phenotypic features of HR, and underscore the potential clinical value of integrating HR screening into antimicrobial susceptibility testing, particularly for high-risk patient populations, to better guide therapy and mitigate the risk of treatment failure.