Objective : To investigate the mechanisms of bromodomain-containing protein 4(BRD4) in TGF-β1-induced epithelial-mesenchymal transition in alveolar type II epithelial cells. Methods : MLE-12 cells were stimulated with different concentrations(5 ng/ml, 10 ng/ml) of TGF-β1 for 48 h to establish an EMT cell model. The cells were pretreated with 50 nmol/L BRD4 inhibitor JQ-1, 100 μmol/L high mobility group box 1 protein(HMGB1)inhibitor glycyrrhizin acid(GA), and 3 μg/ml rHMGB1. The experimental groups were divided as follows: control group, TGF-β1 group, JQ-1 group, JQ-1+TGF-β1 group, GA group, GA+TGF-β1 group, and JQ-1+TGF-β1+rHMGB1 group. The effect of JQ-1 on cell viability was examined using cell counting kit-8(CCK-8). The protein expression levels of CDH1, ZO-1, Vimentin, α-SMA, BRD4, HMGB1, TGF-β1, Smad2/3 and p-Smad2/3 were detected by Western blot. The cell migration ability was detected by a scratch test. Results : Compared with the control group, the levels of Vimentin and α-SMA in the TGF-β1 group increased, and the levels of CDH1 and ZO-1 protein decreased, suggesting that the EMT model was successfully established. In this model, the expression of BRD4 and HMGB1 significantly increased. Different concentrations of JQ-1 could inhibit the cell viability of MLE-12 in a concentration-dependent manner. Both JQ-1 and GA could effectively alleviate TGF-β1-induced EMT, and reduce the increase in HMGB1 expression and the activation of TGF-β1/Smad2/3 pathway caused by TGF-β1. Moreover, rHMGB1 treatment could reduce the effects of JQ-1 on EMT and the TGF-β1/Smad2/3 pathway. Additionally, both JQ-1 and glycyrrhizin could effectively decrease TGF-β1-induced cell migration, whereas rHMGB1 could alleviate the inhibitory effect of JQ-1 on the rate of cell migration. Conclusion BRD4 can regulate epithelial-mesenchymal transition in alveolar type II epithelial cells via HMGB1/TGF-β1/Smad2/3 signaling cascade, and BRD4 may be a potential target for inhibition of pulmonary fibrosis.

Objective:To obtain a polyvalent single-chain variable fragment（scFv）against West Nile virus through PEGylation in order to improve its antigen-binding ability and neutralizing activity.Methods:A scFv carrying a C-terminal cysteine residue（scFvC）was constructed by introducing Cys into the C-terminal of scFv against West Nile virus. Then the multimerization of scFvC was achieved by targeting the thiol group of Cys with maleimide-activated polyethylene glycol. ELISA was used to detect the antigen-binding activity of the multivalent scFvC. Pseudovirus-based neutralization assay was used to evaluate the neutralizing activity of the multivalent scFvC in vitro. One-way analysis of variance was used for statistical analysis. Results:The PEGylated scFvC multimers showed higher antigen-binding ability than the monomeric scFvC. In the pseudovirus-based neutralization assay，both monomeric scFvC and PEGylated scFvC multimers showed good neutralizing activity compared with the control group（ P<0.000 1）. Moreover，the PEGylated scFvC multimers showed a more effective ability to block the pseudovirus infection in target cells（ P<0.05），suggesting that the PEGylated scFvC multimers could enhance their function in vitro through avidity effect. Conclusion:In this study，a scFvC targeting West Nile virus is successfully constructed and its polyvalent form is generated through PEGylation，which improves the antigen-binding and neutralizing activity of the parental scFv.

Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27％.The number of HAI episodes was 38 032,and case prevalence rate was 1.38％.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66％to 2.35％.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65％.The most common infection site was the lower respiratory tract(44.66％),followed by the urinary tract(12.94％),surgical site(9.32％),upper respiratory tract(7.02％),and bloodstream infection(5.78％).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02％),department of neurosurgery(5.51％),and department(group)of hematology(5.34％).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10％)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76％),Pseudomonas aeruginosa(13.33％),Escherichia coli(12.79％),Acinetobacter baumannii(9.23％),and Staphylococcus aureus(7.88％).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71％.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18％.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46％.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.

This paper conducts a systematic literature review to analyze and summarize the current status, admission standards, practical scope, competency requirements, and talent cultivation of public health nursing teams both domestically and internationally, in order to provide reference for the development of public health nursing in China and assist in the improvement of the public health talent team.

This paper conducts a systematic literature review to analyze and summarize the current status, admission standards, practical scope, competency requirements, and talent cultivation of public health nursing teams both domestically and internationally, in order to provide reference for the development of public health nursing in China and assist in the improvement of the public health talent team.

Objective:To obtain a polyvalent single-chain variable fragment（scFv）against West Nile virus through PEGylation in order to improve its antigen-binding ability and neutralizing activity.Methods:A scFv carrying a C-terminal cysteine residue（scFvC）was constructed by introducing Cys into the C-terminal of scFv against West Nile virus. Then the multimerization of scFvC was achieved by targeting the thiol group of Cys with maleimide-activated polyethylene glycol. ELISA was used to detect the antigen-binding activity of the multivalent scFvC. Pseudovirus-based neutralization assay was used to evaluate the neutralizing activity of the multivalent scFvC in vitro. One-way analysis of variance was used for statistical analysis. Results:The PEGylated scFvC multimers showed higher antigen-binding ability than the monomeric scFvC. In the pseudovirus-based neutralization assay，both monomeric scFvC and PEGylated scFvC multimers showed good neutralizing activity compared with the control group（ P<0.000 1）. Moreover，the PEGylated scFvC multimers showed a more effective ability to block the pseudovirus infection in target cells（ P<0.05），suggesting that the PEGylated scFvC multimers could enhance their function in vitro through avidity effect. Conclusion:In this study，a scFvC targeting West Nile virus is successfully constructed and its polyvalent form is generated through PEGylation，which improves the antigen-binding and neutralizing activity of the parental scFv.

Objective:To obtain fucose-free anti-West Nile virus nonstructural protein 1 (NS1) antibody and evaluate its antibody-dependent cell-mediated cytotoxicity (ADCC).Methods:The guanosine diphosphate-fucose transporter SLC35C1 in CHO cells was knocked out using CRISPR/Cas9 gene editing technology to obtain the fucose-free cell line CHO SLC35C1 -/-. CHO SLC35C1 -/- cells were used to produce fucose-free anti-West Nile virus NS1 antibodies. The binding abilities of the antibodies to the target antigen of West Nile virus NS1 protein and the human high-affinity IgG Fc receptor hFcγRⅠ (hCD64) were detected by ELISA and flow cytometry, respectively. The ADCC activity of the antibodies was detected by ADCC reporter gene assay. One-way analysis of variance was used for statistical analysis. Results:CHO SLC35C1 -/- cells expressed green fluorescent protein but not Lens culinaris agglutinin. The anti-West Nile virus NS1 antibodies produced by CHO SLC35C1 -/- cells with a fucose content of 0.22% could bind to West Nile virus NS1 protein in a concentration-dependent manner. Compared with the wild-type antibodies, the fucose-free anti-West Nile virus NS1 antibodies showed a stronger binding ability to hFcγRⅠ(hCD64), as indicated by a significant increase in fluorescence intensity. The ADCC reporter gene assay showed that the fucose-free anti-West Nile virus NS1 antibodies had increased activity as compared with the wild-type antibodies ( P<0.001). Conclusion:The fucose-free anti-West Nile virus NS1 antibodies may be used to protect against West Nile virus infection.

Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27％.The number of HAI episodes was 38 032,and case prevalence rate was 1.38％.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66％to 2.35％.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65％.The most common infection site was the lower respiratory tract(44.66％),followed by the urinary tract(12.94％),surgical site(9.32％),upper respiratory tract(7.02％),and bloodstream infection(5.78％).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02％),department of neurosurgery(5.51％),and department(group)of hematology(5.34％).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10％)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76％),Pseudomonas aeruginosa(13.33％),Escherichia coli(12.79％),Acinetobacter baumannii(9.23％),and Staphylococcus aureus(7.88％).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71％.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18％.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46％.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.

Objective:To obtain fucose-free anti-West Nile virus nonstructural protein 1 (NS1) antibody and evaluate its antibody-dependent cell-mediated cytotoxicity (ADCC).Methods:The guanosine diphosphate-fucose transporter SLC35C1 in CHO cells was knocked out using CRISPR/Cas9 gene editing technology to obtain the fucose-free cell line CHO SLC35C1 -/-. CHO SLC35C1 -/- cells were used to produce fucose-free anti-West Nile virus NS1 antibodies. The binding abilities of the antibodies to the target antigen of West Nile virus NS1 protein and the human high-affinity IgG Fc receptor hFcγRⅠ (hCD64) were detected by ELISA and flow cytometry, respectively. The ADCC activity of the antibodies was detected by ADCC reporter gene assay. One-way analysis of variance was used for statistical analysis. Results:CHO SLC35C1 -/- cells expressed green fluorescent protein but not Lens culinaris agglutinin. The anti-West Nile virus NS1 antibodies produced by CHO SLC35C1 -/- cells with a fucose content of 0.22% could bind to West Nile virus NS1 protein in a concentration-dependent manner. Compared with the wild-type antibodies, the fucose-free anti-West Nile virus NS1 antibodies showed a stronger binding ability to hFcγRⅠ(hCD64), as indicated by a significant increase in fluorescence intensity. The ADCC reporter gene assay showed that the fucose-free anti-West Nile virus NS1 antibodies had increased activity as compared with the wild-type antibodies ( P<0.001). Conclusion:The fucose-free anti-West Nile virus NS1 antibodies may be used to protect against West Nile virus infection.

Background Silicosis is an occupational disease mainly characterized by pulmonary progressive fibrosis induced by the accumulation of free silica (SiO₂) in the lungs due to long-term exposure to SiO₂ dust. It has been shown that neutrophil extracellular traps (NETs) are increased in the lung tissues of silicotic mice after 28 d SiO₂ exposure, but it is unclear how the levels of NETs change throughout entire progression of silicosis in mice. Objective To observe the levels of NETs and pathological changes in the lungs of silicotic mice after different duration of SiO₂ exposure, and to confirm the possible role and significance of NETsin the development of SiO₂-induced pulmonary fibrosis. Methods A total of 28 SPF male C57BL/6J mice were randomly divided into a control group, and a model group, and the model group was subdivided into, a 2 d model group, a 7 d model group, and a 28 d model group, with 7 mice in each group. The mice in the model groups were given intratracheal instillation with 10 mg SiO₂ suspension (50 μL), and the mice in the control group were received same volume of saline. Mice were sacrificed and samples were collected at designed time points. The pathological changes of lung tissues of mice were observed after hematoxylin-eosin (HE) and Van Gieson (VG) staining. Immunofluorescence was used to observe the NETs markers citrullination histone H3 (CitH3) and myeloperoxidase (MPO) in bronchoalveolar lavage fluid (BALF), and the percentage of NETs-positive cells was calculated. PicoGreen fluorescent dye kit was used to detect the content of extracelluar DNA (ex-DNA) in mouse BALF, and the expression levels of fibrosis-related proteins α-smooth muscle actin (α-SMA) and fibronectin (FN) and NETs marker CitH3 in lung tissues of mice were detected by Western blot (WB). Results Compared with the control group, inflammatory cells accumulation, alveolar wall thickening, and collagen deposition were obviously observed in the lungs of the silicosis model groups, and a large number of silicone nodules were recorded in the lung tissues in the 28 d group. Compared with the control group, the expressions of α-SMA and FN in the lung tissue of the 28 d group were significantly increased (P<0.05). The percentages of NETs in BALF increased significantly in the 2 d and the 7 d model group, then decreased in the 28 d model group (P<0.05). Compared with the control group (7.434±0.258) ng·mL⁻¹, the ex-DNA levels in BALF of mice in the 2 d [(35.110±6.331) ng·mL⁻¹], the 7 d [(39.491±6.948) ng·mL⁻¹], and the 28 d [(23.360±4.809) ng·mL⁻¹] model groups were increased (P<0.05), and the increase of ex-DNA in the 2 d and the 7 d model groups were statistically significant (P<0.05). In comparison with the control group, the protein level of CitH3 was significantly increased in the lung tissues of mice in the 7 d model group (P<0.05). Conclusion The content of NETs increases significantly and reaches a peak in the early inflammatory stage of silicosis, and decreases as the disease progresses to the fibrotic stage, suggesting that NETs may play a role in early stage of silicosis.