OBJECTIVE To investigate a suspected hospital-acquired infection cluster of Enterococcus faecium(Efm)in a neonatal intensive care unit(NICU)of the First Medical Center of Chinese PLA General Hospital,identify the source of infection and transmission routes,and provide a reference for precise prevention and control of hospital-acquired infections.METHODS Epidemiological investigations and environmental microbiological sam-pling were conducted for two neonates with Efm bloodstream infections in the NICU in Jul.2024 to detect Efm in the ward environment.Whole-genome average nucleotide identity(ANI)and multilocus sequence typing(MLST)were used to analyze the homology,drug resistance,and virulence factors of Efm isolates from patients and envi-ronments.Targeted intervention measures were proposed.RESULTS Two cases of Efm bloodstream infection were detected.A total of 37 environmental specimens were collected,and 2 were cultured Efm(the wipe dispenser o-pening and incubator handle of the patients).The drug susceptibility testing results of 2 environmental specimens were consistent with those of the two patient specimens.Genomic analysis confirmed high homology(ANI＞99.99％)among the four Efm isolates.After implementing a series of measures including centralized isolation,strict hand hygiene,thorough environmental cleaning and disinfection,strict disinfection and management of inva-sive devices,enhanced grouping of medical staff for diagnosis and treatment,the incident was effectively con-trolled.CONCLUSIONS This incident can be determined as cluster of hospital-acquired infection with Enterococcus faecium in the neonatal intensive care unit.The wet wipes are the source or transmission medium of contamina-tion.Inadequate disinfection of items and the environment,and insufficient hand hygiene of medical staff are the main reasons for this infection outbreak.Early identification of abnormal cluster of infection,investigation of the source of infection and transmission routes and timely implementation of targeted measures are the keys for preventing infection outbreaks.

Healthcare-associated infections(HAIs)represent one of the critical issues affecting the public health security and the quality of medical services.Monitoring,early warning,intervention and feedback for HAIs re-main the cornerstone of infection prevention and control.To systematically understand the progress of surveillance of HAIs in domestic and international regions and summarize the characteristics and variations,this paper compre-hensively reviews the surveillance systems of HAIs from different regions around the globe,their construction and development as well as the diversity,covering the type of surveillance,surveillance idea and standards,the essen-tial characteristics and advancements of the key technologies for HAIs surveillance and application systems were also compared among the regions.The review aims to summarize the general situation of development of HAIs surveillance in different regions around the globe and to provide new ideas for construction and development of HAIs surveillance system.

In recent years,the microorganisms residues in endoscopes have frequently resulted in cross transmis-sion or even the outbreak of hospital-associated infections.It is of great importance to carry out standardized bio-logical surveillance of endoscopes,find out the high-risk links of cleaning and disinfection,and take targeted inter-vention measures to reduce the incidence of endoscopy-related infection.Based on the related guidelines in China and abroad as well as the latest clinical practice researches,the biological surveillance sampling and culture for en-doscopes were summarized in the article so as to enhance the surveillance quality,ensure the reprocessing effect and guarantee the endoscopy-related quality and safety.

OBJECTIVE To systematically analyze the functional system and construction requirements for infection prevention and control('infection control system'in short)in medical institutions so as to facilitate the effective,standardized and practical construction of the infection control system.METHODS The questionnaires were de-signed based on the relevant criteria and literatures that were released in China with the combination of expect con-sultant and were distributed to experts or professionals involving multiple fields such as hospital infection manage-ment,clinical medical treatment and information technology.The questionnaires were recycled,summarized and analyzed.RESULTS The list of functions of the infection control system(consultative draft)was formulated after review of literatures and expert consultation,including fundamental functions such as data management,case sur-veillance and intervention feedback as well as the advanced functions like target surveillance,occupational protec-tion and interconnection.The surveyed subjects agreed unanimously after the questionnaire survey that all of the function modules and elements enlisted were important,the average score of importance was more than 4 points,the score of coefficient of variable(CV)for importance of the function modules was less than 0.25,indicating that there was high consistency in the opinions among the surveyed subjects.The element of tracing and epidemiologi-cal survey function was adopted and added according to the feedback suggestions from some of the subjects;two function elements including data query and clinical interaction were revised,and the list of function requirements for the infection control systems was finally defined.CONCLUSION The requirements for functions of the infection control system that are determined in the study can provide important bases and data support for the research and standardized development of future infection control system.

Natural components serve the survival instincts of cells that are obtained through long-term evolution, while they often fail to meet the demands of engineered cells for efficiently performing biological functions in special industrial environments. Enzymes, as biological catalysts, play a key role in biosynthetic pathways, significantly enhancing the rate and selectivity of biochemical reactions. However, the catalytic efficiency, stability, substrate specificity, and tolerance of natural enzymes often fall short of industrial production requirements. Therefore, exploring and modifying enzymes to suit specific biomanufacturing processes has become crucial. In recent years, artificial intelligence (AI) has played an increasingly important role in the discovery, evaluation, engineering, and de novo design of proteins. AI can accelerate the discovery and optimization of proteins by analyzing large amounts of bioinformatics data and predicting protein functions and characteristics by machine learning and deep learning algorithms. Moreover, AI can assist researchers in designing new protein structures by simulating and predicting their performance under different conditions, providing guidance for protein design. This paper reviews the latest research advances in protein discovery, evaluation, engineering, and de novo design for biomanufacturing and explores the hot topics, challenges, and emerging technical methods in this field, aiming to provide guidance and inspiration for researchers in related fields.
Protein Engineering/methods* ; Artificial Intelligence ; Proteins/genetics* ; Computational Biology ; Machine Learning ; Data Mining ; Algorithms ; Deep Learning

Objective To explore the effect and preliminary mechanism of the plant-derived immunostimulatory molecule,ophiopogonin,on enhancing the immune response of a subunit vaccine with the receptor-binding domain(RBD)of coronavirus spike protein as the antigen.Methods CCK-8 assay was used to determine the cytotoxicity of ophiopogonin D'(OPD')on bone marrow-derived dendritic cells(BMDCs).Female Balb/c mice were randomly divided into RBD,RBD/OPD',RBD/Alum,and control groups.The immunization dose was 5 μg of antigen per mouse and 100 μg of adjuvant per mouse,and immunization was carried out according to the intramuscular injection immunization procedure on days 0,21,and 42.The titers of specific IgG and its subtype antibodies were detected by ELISA.The cytokine levels in the supernatant of splenocytes were detected using ELISA.The number of splenocytes secreting IFN-γ was detected by ELISpot.Laser confocal microscopy was employed to observe the uptake of antigen by BMDCs.The phagocytic ability of BMDCs for antigen was quantitatively analyzed by flow cytometry.The mechanism of its enhanced immune effect was preliminarily explored using transcriptomics technology combined with bioinformatics research.Results When the concentration of OPD'was less than 5 μg/mL,the survival rate of BMDCs was 100%.After a single intramuscular injection in mice,except for a slight decrease in body weight,the other biochemical indicators were within corresponding normal ranges.After intramuscular injection immunization of the vaccine,the titers of serum-specific IgG,IgG1,and IgG2a in the RBD/OPD'group were significantly higher than those in the RBD group(P<0.05).Compared with the RBD group,the RBD/OPD'group induced a high-level Th1 cell immune response of IL-1β,TNF-α,and IFN-γ(P<0.01)and had more lymphocytes secreting IFN-γ(P<0.001).Laser confocal microscopy displayed that BMDCs took up more antigens after OPD'treatment,which was further confirmed with flow cytometry in quantitative analysis on antigen uptake rate(P<0.01).Transcriptomics results indicated that there was more significant enrichment of the PPAR signaling pathway in the RBD/OPD'group than the RBD group,suggesting that OPD'may activate the PPAR signaling pathway to exert its adjuvant effect.Conclusion OPD'effectively enhances the immune response of the RBD subunit vaccine,and its action mechanism may be related to the activation of the PPAR signaling pathway.

Objective To establish a mouse model of infection with the minimum lethal dose of Vibrio vulnificus(V.vulnificus)and to evaluate the protective efficacy of inactivated whole-cell(IWC)vaccine using this model.Methods A mouse model of lethal-dose infection was established by intraperitoneal injection of different doses of V.vulnificus.Bacterial colonization in the organs was detected with tissue homogenate plating,and pathological changes in the organs were observed after tissue section staining.Flow cytometry was used to detect immune cell responses after liver tissues were digested into single-cell suspension.IWC vaccine of V.vulnificus was prepared,and the mice were immunized through different routes to observe the protective efficacy of the vaccine.Results A mouse model of infection with the minimum lethal dose at 1×106 CFU of V.vulnificus was successfully established.After infection,the bacteria were mainly colonized in the liver of mice and caused severe pathological damages.Compared with the uninfected mice,the proportion of neutrophils in the liver was significantly increased in the infected mice,whereas the proportions of B cells and T cells were correspondingly decreased(P<0.05).A single intramuscular or intraperitoneal injection of the IWC vaccine could protect the mice effectively against lethal infection of V.vulnificus in 7 d later(P<0.01),although the level of serum IgG having no significant increase.Conclusion A mouse model of lethal-dose infection with V.vulnificus is successfully established,with histopathological characteristics.The IWC vaccine of V.vulnificus rapidly mediates immune protection in this model probably independent of IgG.

Objective To prepare tubeimoside Ⅲ nanoemulsion(TBMⅢ-NE)and evaluate its adjuvant effect in vaccines.Methods TBMⅢ-NE was prepared using low-energy emulsification.Dynamic light scattering was used to characterize the particle size and polydispersity index of the obtained TBMⅢ-NE,and transmission electron microscopy(TEM)was employed to observe the morphology.CCK-8 assay was utilized to determine the cytotoxicity of TBMⅢ-NE on bone marrow-derived dendritic cells(BMDCs).The in vitro safety of TBMⅢ-NE was evaluated using a hemolysis assay.The ability of TBMⅢ-NE to promote the phagocytosis of antigens by DC2.4 cells was observed using confocal laser microscopy.After co-incubation of TBMⅢ-NE with BMDCs,the expression levels of CD40,CD86,MHC-Ⅰ,and CCR7 on the surface of BMDCs were detected using flow cytometry,and the levels of cytokines in the supernatant of BMDCs were measured using enzyme-linked immunosorbent assay(ELISA).After female BALB/c mice were immunized with the SARS-CoV-2 antigen RBD in combination with TBMⅢ-NE,ELISA was conducted to determine the serum levels of specific IgG,IgG2a,and IgG1 antibodies.The number of specific IFN-γ-secreting cells in mouse splenocytes was detected using enzyme-linked immunospot(ELISpot)assay.Results The prepared blank nanoemulsion(BNE)and TBMⅢ-NE were in a particle size of 25.46 and 25.89 nm,and a polydispersity index of 0.214 and 0.125,respectively.TEM displayed that TBMⅢ-NE was in uniform sphere and well dispersed.When the TBMⅢ-NE adjuvant was diluted by 400-fold,the survival rate of BMDCs was approximately 86%.Compared with free TBMⅢ,the hemolytic toxicity of TBMⅢ-NE was significantly reduced(P<0.01).TBMⅢ-NE promoted the phagocytosis of antigens by DC2.4 cells and significantly increased the expression of CCR7 on the surface of BMDCs(P<0.05),indicating its potential to promote more dendritic cells to effectively migrate to lymph nodes.TBMⅢ-NE also promoted the expression of IL-6 and IL-1β in the supernatant of BMDCs(P<0.05).When combined with RBD,TBMⅢ-NE significantly increased the levels of specific IgG,IgG2a,and IgG1 antibodies in mouse serum(P<0.01)and promoted the secretion of specific IFN-γ in splenocytes(P<0.01),indicating that TBM Ⅲ-NE could enhance specific cellular immune responses.Conclusion A stable and highly effective TBMⅢ-NE that can induce humoral and cellular immune responses is successfully prepared.

Objective:To explore the therapeutic effect of compound Kuijie Ankang Decoction on ulcerative colitis (UC) model mice by non targeted metabonomics; To explore its mechanism.Compound Kuijie Ankang.Methods:The mice were randomly divided into blank control group, model group, Kuijie Ankang Decoction group and sulfasalazine group, with 12 mice in each group. Except the blank control group, the other groups were given 1.5% DSS solution for free drinking to prepare UC model. After successful modeling, Kuijie Ankang Decoction group was intragastrically administered with compound Kuijie Ankang Decoction of 9.68 g/kg, sulfasalazine group was intragastrically administered with sulfasalazine capsule suspension of 320 mg/kg, model group and blank control group were intragastrically administered with equal volume of purified water, once a day, for 7 consecutive days. The body mass and disease activity index (DAI) score of mice were measured. ELISA was used to measure the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) in the colon tissue of mice; the protein expressions of Claudin-1 and Zo-1 in colon tissue were detected by immunofluorescence method. HE staining was used to observe the pathological changes in the colon, and UHPLC-OE-MS technology was used to analyze the endogenous metabolite structure of mouse colon tissue, differential metabolites and related metabolic pathways were screened.Results:Compared with the model group, the colon length in Kuijie Ankang Decoction group and sulfasalazine group increased ( P<0.01), the DAI score decreased ( P<0.01), the levels of TNF-α, IL-1β and IL-6 in colon tissue decreased ( P<0.01), the level of IL-10 increased ( P<0.01), and the average optical density of Claudin-1 and Zo-1 protein increased ( P<0.01 or P<0.05). Metabolomics analysis identified 26 potential differential metabolites, including nicotinamide adenine dinucleotide, guanine, gamma aminobutyric acid, and thiamine, affecting 26 key metabolic pathways, including lysine biosynthesis, thiamine metabolism, cysteine and methionine metabolism. Conclusion:Kuaijie Ankang Decoction may improve metabolites such as Gamma aminobutyric acid and thiamine through metabolic pathways such as lysine biosynthesis to alleviate inflammatory reactions, thereby exerting therapeutic effects on ulcerative colitis in mice.

ObjectiveTo explore the central neuroregulation mechanism of heat-sensitive moxibustion for knee osteoarthritis on pain relief. MethodsThirty patients who did not have experience of Deqi （得气） during heat-sensitive moxibustion treatment were assigned to the "non-Deqi group"， while another 30 patients who had experience of Deqi were assigned to the "Deqi group". Both groups received moxibustion at the left Heding （EX-LE2） acupoint. In the Deqi group， after the patients experienced sensation of Deqi at the acupoint， moxibustion was applied at approximately 3 cm from the skin for 10 minutes； in the non-Deqi group， moxibustion was also applied at approximately 3 cm from the skin for 10 minutes. Both groups received treatment once daily for 10 consecutive days. Knee joint pain was assessed before and after treatment using the visual analog scale （VAS）. Resting-state functional magnetic resonance imaging （rs-fMRI） scans were performed on all participants before the first treatment session and after the final session on the 10th day. The fractional amplitude of low-frequency fluctuations （fALFF） maps before and after treatment were processed using the SPM12 module by MATLAB. ResultsAfter treatment， VAS scores in both groups were significantly lower than before treatment （P＜0.05 or P＜0.01）， with the Deqi group showing significantly lower VAS scores than the non-Deqi group （P＜0.01）. Compared to before treatment， the Deqi group exhibited significant activation in the prefrontal cortex （t = 6.28）， white matter （t = 6.36）， and left temporal lobe （t = 9.33）， while significant inhibition was observed in the occipital lobe （t = -9.86） and right cerebrum （t = -4.54， P＜0.01）； in the non-Deqi group， significant changes after treatment were observed in the left occipital lobe （t = -6.42）， left medial frontal gyrus （t = -4.35）， left middle frontal gyrus （t = -4.74）， right superior frontal gyrus （t = -4.82）， right superior temporal gyrus （t = -6.61）， and right cerebellar posterior lobe （t = -8.64）， all of which were in inhibited states （P＜0.01）. Compared to the non-Deqi group， the Deqi group exhibited significant activation after treatment in the external nucleus （t = 5.77）， white matter （t = 3.58）， right cerebrum （t = 5.84）， left cerebellum （t = 5.35）， and left cerebrum （t = 4.32）， while significant inhibition was observed in the prefrontal cortex （t = -4.16）， occipital lobe （t = -4.87）， and precentral gyrus （t = -4.46， P＜0.01）. ConclusionsHeat-sensitive moxibustion provides better analgesic effects for knee osteoarthritis under state of Deqi. Its central neuroregulation mechanism may be related to the involvement of the frontal lobe， temporal lobe， occipital lobe， external nucleus， white matter， right cerebrum， left cerebellum， left cerebrum， and precentral gyrus in modulating pain signals.