Animal experimentation constitutes a critical link between basic research and clinical application, making its research quality and translational efficiency paramount. Although considerable progress has been made in standardizing operational procedures and ethical guidelines, the standardization of outcome evaluation systems has significantly lagged, creating a key bottleneck that constrains the quality of biomedical research and evidence synthesis. This deficiency is manifested by pronounced heterogeneity in outcome selection across similar studies, incomplete methodological reporting, and disparate criteria for result interpretation, which severely impairs the comparability of findings and the evidence integration. To cope with this challenge, this paper systematically introduces a mature methodological tool from clinical research–the core outcome set (COS)–and explores its construction strategies and application potential in the field of animal experimentation. Given the extensive diversity of animal experiments, a pragmatic strategy of "focusing on key areas, implementing phased pilots, and promoting gradual expansion" should be adopted. This approach prioritizes the development of domain-specific COS for disease areas characterized by high research volume, urgent translational needs, and well-established animal models. A multi-source integration pathway for COS development is detailed, comprising systematic literature searches, methodological appraisals, and expert consensus, with the feasibility of leveraging artificial intelligence (AI) to enhance efficiency also being examined. The development and promotion of such COS are not intended to restrict scientific exploration; rather, they aim to establish a new, tiered evaluation paradigm consisting of "core outcomes" (mandatory), "recommended outcomes" (encouraged), and "exploratory outcomes" (optional). This framework is expected not only to enhance research quality through standardization and to adhere to the "3R" principles but also to accelerate the accumulation of high-quality evidence. This, in turn, provides a solid foundation for higher-level evidence synthesis, ultimately facilitating the effective translation of basic research findings into clinical practice and providing an essential methodological framework for scientific advancement in relevant disciplines.

Background: Diabetic pain patients have increased pain at night. Exosomes can relieve neuropathic pain. This study aimed to investigate the efficacy of exosome administration at different time points in relieving diabetic neuropathic pain (DNP) in rats. Methods: M2 macrophages from bone marrow were induced in mice and exosomes were extracted. A diabetic rat model was induced using streptozotocin, with the mechanical withdrawal threshold (MWT) of the rats beingmeasured at ≤ 80% of the basal value after 14 days, indicating successful construction of the DNP rat model.Exosomes were administered on three consecutive days at ZT0 (zeitgeber time) and ZT12. Parameters including blood glucose levels, body weight, MWT, and thermal withdrawal latency (TWL) were assessed in the rats. The lumbar spinal cord of rats was examined on days 21 and 28 to measure inflammatory factors and observe the expression of M1 and M2 microglia. Furthermore, microglia were exposed to lipopolysaccharide (LPS) and LPS + exosomes in a controlled in vitro setting to assess alterations in microglia phenotype involving the NF-kB p65 andIKBα inflammatory signaling pathways. Results: The findings revealed that administration of exosomes during the rat resting period at ZT12 resulted in increased MWT and TWL, as well as a shift in microglia polarization towards the M2 phenotype. In vitro analysis indicated that exosomes influenced microglia polarization and suppressed the phosphorylation of NF-kB p65 andIKBα.  Conclusions Temporal therapy with exosomes effectively reduces pain in DNP rats by polarizing microglia andaffecting NF-kB p65 and IKBα signaling pathways.

Background: Diabetic pain patients have increased pain at night. Exosomes can relieve neuropathic pain. This study aimed to investigate the efficacy of exosome administration at different time points in relieving diabetic neuropathic pain (DNP) in rats. Methods: M2 macrophages from bone marrow were induced in mice and exosomes were extracted. A diabetic rat model was induced using streptozotocin, with the mechanical withdrawal threshold (MWT) of the rats beingmeasured at ≤ 80% of the basal value after 14 days, indicating successful construction of the DNP rat model.Exosomes were administered on three consecutive days at ZT0 (zeitgeber time) and ZT12. Parameters including blood glucose levels, body weight, MWT, and thermal withdrawal latency (TWL) were assessed in the rats. The lumbar spinal cord of rats was examined on days 21 and 28 to measure inflammatory factors and observe the expression of M1 and M2 microglia. Furthermore, microglia were exposed to lipopolysaccharide (LPS) and LPS + exosomes in a controlled in vitro setting to assess alterations in microglia phenotype involving the NF-kB p65 andIKBα inflammatory signaling pathways. Results: The findings revealed that administration of exosomes during the rat resting period at ZT12 resulted in increased MWT and TWL, as well as a shift in microglia polarization towards the M2 phenotype. In vitro analysis indicated that exosomes influenced microglia polarization and suppressed the phosphorylation of NF-kB p65 andIKBα.  Conclusions Temporal therapy with exosomes effectively reduces pain in DNP rats by polarizing microglia andaffecting NF-kB p65 and IKBα signaling pathways.

Background: Diabetic pain patients have increased pain at night. Exosomes can relieve neuropathic pain. This study aimed to investigate the efficacy of exosome administration at different time points in relieving diabetic neuropathic pain (DNP) in rats. Methods: M2 macrophages from bone marrow were induced in mice and exosomes were extracted. A diabetic rat model was induced using streptozotocin, with the mechanical withdrawal threshold (MWT) of the rats beingmeasured at ≤ 80% of the basal value after 14 days, indicating successful construction of the DNP rat model.Exosomes were administered on three consecutive days at ZT0 (zeitgeber time) and ZT12. Parameters including blood glucose levels, body weight, MWT, and thermal withdrawal latency (TWL) were assessed in the rats. The lumbar spinal cord of rats was examined on days 21 and 28 to measure inflammatory factors and observe the expression of M1 and M2 microglia. Furthermore, microglia were exposed to lipopolysaccharide (LPS) and LPS + exosomes in a controlled in vitro setting to assess alterations in microglia phenotype involving the NF-kB p65 andIKBα inflammatory signaling pathways. Results: The findings revealed that administration of exosomes during the rat resting period at ZT12 resulted in increased MWT and TWL, as well as a shift in microglia polarization towards the M2 phenotype. In vitro analysis indicated that exosomes influenced microglia polarization and suppressed the phosphorylation of NF-kB p65 andIKBα.  Conclusions Temporal therapy with exosomes effectively reduces pain in DNP rats by polarizing microglia andaffecting NF-kB p65 and IKBα signaling pathways.

Background: Diabetic pain patients have increased pain at night. Exosomes can relieve neuropathic pain. This study aimed to investigate the efficacy of exosome administration at different time points in relieving diabetic neuropathic pain (DNP) in rats. Methods: M2 macrophages from bone marrow were induced in mice and exosomes were extracted. A diabetic rat model was induced using streptozotocin, with the mechanical withdrawal threshold (MWT) of the rats beingmeasured at ≤ 80% of the basal value after 14 days, indicating successful construction of the DNP rat model.Exosomes were administered on three consecutive days at ZT0 (zeitgeber time) and ZT12. Parameters including blood glucose levels, body weight, MWT, and thermal withdrawal latency (TWL) were assessed in the rats. The lumbar spinal cord of rats was examined on days 21 and 28 to measure inflammatory factors and observe the expression of M1 and M2 microglia. Furthermore, microglia were exposed to lipopolysaccharide (LPS) and LPS + exosomes in a controlled in vitro setting to assess alterations in microglia phenotype involving the NF-kB p65 andIKBα inflammatory signaling pathways. Results: The findings revealed that administration of exosomes during the rat resting period at ZT12 resulted in increased MWT and TWL, as well as a shift in microglia polarization towards the M2 phenotype. In vitro analysis indicated that exosomes influenced microglia polarization and suppressed the phosphorylation of NF-kB p65 andIKBα.  Conclusions Temporal therapy with exosomes effectively reduces pain in DNP rats by polarizing microglia andaffecting NF-kB p65 and IKBα signaling pathways.

Background: Diabetic pain patients have increased pain at night. Exosomes can relieve neuropathic pain. This study aimed to investigate the efficacy of exosome administration at different time points in relieving diabetic neuropathic pain (DNP) in rats. Methods: M2 macrophages from bone marrow were induced in mice and exosomes were extracted. A diabetic rat model was induced using streptozotocin, with the mechanical withdrawal threshold (MWT) of the rats beingmeasured at ≤ 80% of the basal value after 14 days, indicating successful construction of the DNP rat model.Exosomes were administered on three consecutive days at ZT0 (zeitgeber time) and ZT12. Parameters including blood glucose levels, body weight, MWT, and thermal withdrawal latency (TWL) were assessed in the rats. The lumbar spinal cord of rats was examined on days 21 and 28 to measure inflammatory factors and observe the expression of M1 and M2 microglia. Furthermore, microglia were exposed to lipopolysaccharide (LPS) and LPS + exosomes in a controlled in vitro setting to assess alterations in microglia phenotype involving the NF-kB p65 andIKBα inflammatory signaling pathways. Results: The findings revealed that administration of exosomes during the rat resting period at ZT12 resulted in increased MWT and TWL, as well as a shift in microglia polarization towards the M2 phenotype. In vitro analysis indicated that exosomes influenced microglia polarization and suppressed the phosphorylation of NF-kB p65 andIKBα.  Conclusions Temporal therapy with exosomes effectively reduces pain in DNP rats by polarizing microglia andaffecting NF-kB p65 and IKBα signaling pathways.

Objective To establish a mouse model of bronchiectasis with acute infection and evaluate the immunogenicity and protective effect of a self-assembling Pseudomonas aeruginosa(PA)nanoparticle vaccine rePO-FN based on fusion of PcrV-OprI(rePO)protein with self-assembling ferritin(Ferritin).Methods ① SPF-grade female C57BL/6 mice(aged 6～8 weeks,weighing 18～20 g)were randomly allocated into normal saline group,and low-,medium-and high-dose elastase groups(n=6).A mouse model of bronchiectasis was established via intratracheal instillation of different doses of elastase(30 μL of normal saline containing 0.65,1.30 and 2.60 IU elastase)for 3 consecutive days.At 14 and 21 d after modeling,ELISA and HE staining were performed respectively to detect the concentration of IL-6 and to observe pathological changes in lung tissue in order to confirm the modeling.② A recombinant plasmid encoding the gene of fusion protein rePO-FN was constructed and expressed in E.coli.The target protein was purified via affinity chromatography and renatured to obtain the desired protein.The physicochemical properties of the rePO-FN protein were characterized using SDS-PAGE protein gel electrophoresis,dynamic light scattering,molecular sieve chromatography,and transmission electron microscopy.③ C57BL/6J mice were randomly divided into PBS group,rePO group,rePO-FN group,and Ferritin group(n=10).The mice in the above groups were immunized intramuscularly with 100 μL PBS buffer alone or containing 10 μg of corresponding proteins on days 0,7,and 14.ELISA was used to measure the specific antibodies in serum.In 7 d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the PBS,rePO,and rePO-FN groups.After establishing a bronchiectasis model by intratracheal instillation of 2.60 IU of elastase in C57BL/6J mice as described above,the mice were randomly divided into bronchiectasis PBS group,bronchiectasis rePO group,and bronchiectasis rePO-FN group(n=10).Immunization was conducted at the same dose and procedure as described above,in 21 d after bronchiectasis modeling.At the 7th d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the groups.Results ①Repeated intratracheal instillation of elastase significantly increased the concentration of IL-6 in the lung tissue when compared to the content of the normal saline group(P＜0.05).Pathological observations revealed varying degrees of bronchial wall destruction,alveolar fusion,edema,neutrophil infiltration,and hemorrhage,with the severity increasing with elastase dose,which confirming successful establishment of the mouse model of bronchiectasis.② Well-dispersed rePO-FN nanoparticles were successfully prepared,with an average particle size of 91.28 nm,a Zeta potential of approximately-6.5 mV,and a polydispersity index(PDI)of 0.306.Molecular sieve chromatography determined the elution volume of rePO-FN protein to be 8.80 mL,corresponding to a molecular weight of approximately 1 400 kDa.③ Under acute PA XN-1 strain infection,the survival rate of the rePO-FN immunization group and the bronchiectasis rePO-FN immunization group were significantly higher than that of the PBS control group(P＜0.05).Additionally,bacterial colonization in the lung tissues was significantly lower in the rePO-FN immune group and the bronchiectasis rePO-FN immune group under acute PA XN-1 strain infection than that in the rePO group and the bronchiectasis rePO group(P＜0.05).Conclusion Our vaccine rePO-FN can effectively trigger a strong humoral immune response and provide significant protection against PA infection in a mouse bronchiectasis model.

Objective To investigate the effect of Saikosaponin A(SSA)on the differentiation,apoptosis and function of mouse bone marrow derived macrophages(BMDM)-derived M1/M2 macrophages,and to explore its molecular mechanism.Methods BMDM was induced to differentiate into M1/M2 macrophages in vitro,and SSA was added at the same time:CCK-8 assay was used to detect the viability of BMDM and M1/M2 macrophages.The morphology of M1/M2 macrophages was observed by inverted fluorescence microscopy.Flow cytometry(FCM)and ELISA were used to detect the levels of surface markers and cytokines in M1/M2 macrophages.Real-time fluorescent quantitative PCR(qPCR)was used to detect the mRNA levels of IL-6,TNF-α and arginase-1(Arg-1).FCM was used to detect the phagocytosis of peritoneal macrophages to fluorescent microsphere particles.Immunofluorescence(IF)assay and Western blotting were used to detect the molecular mechanism of SSA regulating M1/M2 macrophages.Results No significant effect on viability of M1/M2 macrophages was observed at SSA concentration of 10.0 mg/L,and obvious inhibition was seen at a concentration of 15.0 mg/L(P<0.01).Treatment of 10.0 mg/L SSA induced obvious morphologic changes in M1/M2 macrophages,with M1 macrophages in irregular shape,a few having pseudopods,and some showing unclear boundaries;while some M2 macrophages presenting round or irregular(P<0.001)with unclear boundaries.SSA treatment also resulted in significantly decreased proportion of M1/M2 macrophages after BMDM differentiation(P<0.05),with reduced contents of IL-6 and TNF-α secreted by M1 macrophages and their mRNA levels(P<0.05),but increased secretion of Arg-1 and mRNA levels by M2 macrophages(P<0.05).SSA treatment also inhibited the phagocytosis ability of peritoneal macrophages to fluorescent microsphere particles(P<0.01)in a concentration-dependent manner.SSA decreased the phosphorylation of NF-kappaB(p-NF-κB)(P<0.01)and enhanced the phosphorylation of signal transducer and activator of transcription 6(p-STAT6)in M2 macrophages(P<0.05).Conclusion SSA may affect the differentiation and function of M1/M2 macrophages by regulating NF-κB and STAT6 signaling pathways.

Objective:To analyze the drug resistance characteristics of Klebsiella pneumoniae in the nasopharynx of hospitalized patients in North China from 2022 to 2023. Methods:From November 2022 to July 2023, nasopharyngeal swabs were collected from 100 inpatients in Affiliated Hospital of North China University of Science and Technology, and Klebsiella pneumoniae was isolated and cultured. At the same time, the clinical data of the patients were collected, including gender, age, department, clinical diagnosis of disease type, etc. The minimum inhibitory concentration of strains was detected by an automatic bacterial drug sensitivity system. The drug resistance genes, ST types, capsule serotypes and population structure of the strains were analyzed by whole genome sequencing and data analysis. Results:Klebsiella pneumoniae was isolated from 55 nasopharyngeal swabs of 100 inpatients(55.00%). Among the 55 inpatients with Klebsiella pneumoniae in the nasopharynx, 70.91% (39/55) were male, with an age distribution concentrated between 61 and 80 years old (58.18%, 32/55), and 50.91% (28/55) were in intensive care units (ICU). The main underlying disease type was nervous system disease (49.09%, 27/55). The results of drug sensitivity showed that the non-susceptibility rates of 55 strains of Klebsiella pneumoniae to cephalosporins, quinolones, aztreonam and nitrofurantoin were all more than 80.00%. Twenty-eight carbapenem-resistant Klebsiella pneumoniae strains (50.91%), 47 extended-spectrum β-lactamase producing strains (85.45%), and 48 multi-drug-resistant strains (87.27%) were detected. A total of 11 antibiotic resistance genes were detected, including carbapenems (carrying rate 76.36%) and extended-spectrum β-lactamase (carrying rate 96.36%). The 55 strains could be divided into 17 ST types, and the most common type was ST11 (25.45%). The 55 strains were divided into 18 capsular serotypes, among which K102 was the most prevalent (23.64%). OXA-1_ST307_K102 (21.82%) and KPC-2_ST5492_K125 (18.18%) were the dominant clones, distributed in the Department of Neurosurgery and ICU. The result of whole genome sequence analysis showed that there were four clusters with high homology among the 55 strains. The strains from the ICU formed two independent clusters, and strains from the Neurology ICU and Neurosurgery department formed one cluster respectively. Conclusion:The carrying rate of Klebsiella pneumoniae in the nasopharynx of inpatients is high, and the drug resistance of the strains is serious. There are many types of drug-resistant genes.

Objective:To analyze the drug resistance characteristics of Klebsiella pneumoniae in the nasopharynx of hospitalized patients in North China from 2022 to 2023. Methods:From November 2022 to July 2023, nasopharyngeal swabs were collected from 100 inpatients in Affiliated Hospital of North China University of Science and Technology, and Klebsiella pneumoniae was isolated and cultured. At the same time, the clinical data of the patients were collected, including gender, age, department, clinical diagnosis of disease type, etc. The minimum inhibitory concentration of strains was detected by an automatic bacterial drug sensitivity system. The drug resistance genes, ST types, capsule serotypes and population structure of the strains were analyzed by whole genome sequencing and data analysis. Results:Klebsiella pneumoniae was isolated from 55 nasopharyngeal swabs of 100 inpatients(55.00%). Among the 55 inpatients with Klebsiella pneumoniae in the nasopharynx, 70.91% (39/55) were male, with an age distribution concentrated between 61 and 80 years old (58.18%, 32/55), and 50.91% (28/55) were in intensive care units (ICU). The main underlying disease type was nervous system disease (49.09%, 27/55). The results of drug sensitivity showed that the non-susceptibility rates of 55 strains of Klebsiella pneumoniae to cephalosporins, quinolones, aztreonam and nitrofurantoin were all more than 80.00%. Twenty-eight carbapenem-resistant Klebsiella pneumoniae strains (50.91%), 47 extended-spectrum β-lactamase producing strains (85.45%), and 48 multi-drug-resistant strains (87.27%) were detected. A total of 11 antibiotic resistance genes were detected, including carbapenems (carrying rate 76.36%) and extended-spectrum β-lactamase (carrying rate 96.36%). The 55 strains could be divided into 17 ST types, and the most common type was ST11 (25.45%). The 55 strains were divided into 18 capsular serotypes, among which K102 was the most prevalent (23.64%). OXA-1_ST307_K102 (21.82%) and KPC-2_ST5492_K125 (18.18%) were the dominant clones, distributed in the Department of Neurosurgery and ICU. The result of whole genome sequence analysis showed that there were four clusters with high homology among the 55 strains. The strains from the ICU formed two independent clusters, and strains from the Neurology ICU and Neurosurgery department formed one cluster respectively. Conclusion:The carrying rate of Klebsiella pneumoniae in the nasopharynx of inpatients is high, and the drug resistance of the strains is serious. There are many types of drug-resistant genes.