ObjectiveTo investigate the effect of mitochondrial calcium uniporter （MCU） on the cytoskeleton of pancreatic ductal epithelial cells in a mouse model of acute pancreatitis （AP） induced by caerulein （CAE）， to analyze the role of MCU in the development of AP， and to provide a theoretical basis for clinical treatment. MethodsIn the in vivo experiment， wild-type male C57BL6/J mice， aged 4 weeks， were randomly divided into control group and AP group， with 6 mice in each group. The mice in the AP group were given intraperitoneal injection of CAE to establish a model of AP， and those in the control group were given intraperitoneal injection of an equal volume of normal saline. Serum and pancreatic tissue samples were collected after 24 hours of modeling. HE staining was used to observe pancreatic histopathological changes； Western Blot was used to measure the expression levels of MCU， glutathione peroxidase 4 （GPX4）， and acyl-CoA synthetase long chain family member 4 （ASCL4）； kits were used to measure the serum level of amylase. In the in vitro experiment， the human pancreatic ductal epithelial cell line HPDE6-C7 was co-cultured with CAE for 24 hours to establish an in vitro AP model， and the cells were divided into control group， CAE group， RR （an MCU activity inhibitor） group， CAE+RR group， Fer-1 （an ferroptosis inhibitor） group， CAE+Fer-1 group， Erastin （an ferroptosis inducer） group， and CAE+Erastin group. CCK-8 assay was used to observe the influence of different agents on cell viability； Western Blot was used to measure the expression levels of MCU， GPX4， and ASCL4； immunofluorescence assay was used to measure reactive oxygen species （ROS）， actin cytoskeleton， and monolayer permeability； kits were used to measure the concentrations of malondialdehyde （MDA）， glutathione （GSH）， Fe²⁺， and total iron. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for comparison between two groups. ResultsIn the in vivo experiment， compared with the control group， the AP group had significant increases in pancreatic histopathological score， the serum level of amylase， and the expression levels of MCU and ASCL4， as well as a significant reduction in the expression of GPX4 （all P<0.05）. In the in vitro experiment， compared with the control group， the CAE group had significant increases in the expression levels of MCU and ASCL4， a significant reduction in the expression of GPX4， and significant increases in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability， as well as a significant reduction in the concentration of GSH （all P<0.05）， with the presence of actin cytoskeleton disruption. Compared with the CAE group， the CAE+RR group had a significant increase in the expression level of GPX4， a significant reduction in the expression level of ASCL4， and significant reductions in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant increase in the concentration of GSH （all P<0.05）， with alleviation of actin cytoskeleton disruption. Compared with the CAE group， the CAE+Fer-1 group had significant reductions in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant increase in the concentration of GSH （all P<0.05）， with alleviation of actin cytoskeleton disruption. Compared with the CAE group， the CAE+Erastin group had significant increases in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant reduction in the concentration of GSH （all P<0.05）， with aggravation of actin cytoskeleton disruption. ConclusionDuring the onset of AP， MCU mediates oxidative stress-induced ferroptosis and leads to the disruption of the pancreatic ductal epithelial barrier， which may be one of the possible pathogeneses of AP.

Objective To analyze the genetic characteristics and variations of influenza A (H3N2) viruses in Ma'anshan from 2022 to 2024, and to provide a scientific basis for local influenza prevention and control. Methods From April 2022 to March 2024, influenza-like illness (ILI) specimens were collected from three national influenza surveillance sentinel hospitals in Ma’anshan. Samples positive for influenza by real-time PCR were subjected to virus culture and identification. A total of 40 representative A/H3N2 strains with hemagglutination titers ≥8 were selected for whole-genome sequencing. Genetic evolution, homology, amino acid variations, and glycosylation sites were analyzed. Results All H3N2 representative strains from the 2022–2023 influenza season belonged to clade 3C.2a1b.2a.1a.1, while those from the 2023–2024 season fell into clade 3C.2a1b.2a.2a.3a.1. The nucleotide and amino acid sequence similarities of HA and NA between the 40 representative strains and the vaccine strain A/Darwin/6/2021 were all above 97.35%. Compared with the vaccine strain, amino acid mutations were identified in antigenic sites A, B, C, and E, as well as in receptor-binding sites of the HA protein. An I222V substitution was detected in the NA protein. The HA protein contained four additional glycosylation sites compared to the vaccine strain, while the glycosylation pattern of the NA protein remained consistent. Conclusion No antigenic drift was observed in the influenza A/H3N2 viruses in Ma'anshan City from 2022 to 2024, but genetic changes such as branching variations, key amino acid substitutions, and an increase in HA glycosylation sites were observed. These findings underscore the importance of sustained molecular surveillance of local influenza viruses.

ObjectiveTo investigate the contamination status of ochratoxin A (OTA) in commercially available food products in Shanghai, and to assess OTA exposure levels and the associated non-carcinogenic and carcinogenic risks among pregnant women by integrating dietary consumption data of this population. MethodsThe levels of OTA contamination in 1 520 food samples collected in Shanghai from 2022 to 2023 were determined using liquid chromatography-tandem mass spectrometry. An exposure assessment model was developed based on the dietary consumption levels of pregnant women from the 2016‒2017 Shanghai Pregnant Women Dietary Monitoring Survey to calculate the estimated daily intake (EDI) of OTA, the margin of exposure for non-carcinogenic toxicity (MOE₁), and the margin of exposure for carcinogenic toxicity (MOE₂). An MOE₁ greater than 200 and an MOE₂ greater than 10 000 indicate that the non-carcinogenic toxicity and carcinogenic toxicity resulting from exposure are negligible, respectively. For samples with OTA contamination levels below the limit of detection (LOD), which accounted for more than 80% of the samples, the OTA levels were assigned values of 0 and LOD, respectively, for subsequent calculations. ResultsThe detection rates of OTA in cereals, nuts, dried fruits, and alcohol samples collected in 2022 were 2.03%, 0, 0, and 0, respectively. The OTA detection rates in cereals, nuts, dried fruits, beans, and alcohol samples collected in 2023 were 2.50%, 0.39%, 2.47%, 1.67%, and 13.33%, respectively. For pregnant women in Shanghai in 2022, simulation results indicated that when assigning a value of 0 and the LOD, theP₅₀ values of EDI for dietary OTA exposure were 0.05 and 0.72 ng·(kg·d)^-1, respectively, and the P₉₅ values of EDI for dietary OTA exposure were 0.25 and 2.40 ng·(kg·d)^-1, respectively. For pregnant women in Shanghai in 2023, the P₅₀ values of EDI for dietary OTA exposure were 0.04 and 1.00 ng·(kg·d)^-1, respectively, and the P₉₅ values of EDI for dietary OTA exposure were 0.23 and 2.67 ng·(kg·d)^-1, respectively, both substantially below the tolerable daily intake (TDI) for OTA [17 ng·(kg·d)^-1]. The EDI for dietary OTA exposure in 100.0% of Shanghai pregnant women was lower than the TDI, indicating an overall low level of dietary OTA exposure among this population. For 100.0% of pregnant women, the MOE₁ for dietary OTA exposure exceeded 200. When assigned a value of 0, the MOE₂ for 100.0% of pregnant women in both 2022 and 2023 exceeded10 000. When assigned the LOD value, 72.3% and 81.8% of pregnant women in 2022 and 2023, respectively, had an MOE₂ exceeding 10 000. ConclusionFrom 2022 to 2023, samples of cereals, nuts, dried fruits, beans, and alcohol sold in Shanghai exhibited varying degrees of OTA contamination. The overall EDI of OTA exposure among pregnant women in Shanghai remained at a low level. The non-carcinogenic and carcinogenic risks associated with OTA exposure were generally low and at controllable levels.

ObjectiveTo investigate the mechanism of action of remifentanil （RMZL） in alleviating lung ischemia-reperfusion injury （LIRI） in rats by inhibiting pyroptosis through modulating hypoxia inducible factor-1α （HIF-1α）/NOD-like receptor thermal protein domain associated protein 3 （NLRP3） pathway. MethodsRats were stochastically assigned into Control group， LIRI group， RMZL low-dose group， RMZL medium-dose group， RMZL high-dose group， and RMZL high-dose+HIF-1α activator dimethyloxallyl glycine （DMOG） group， with 18 rats in each group. Rats in Control group only had their left pulmonary hilum free and did not undergo ischemia-reperfusion treatment. Except for the Control group， LIRI models were constructed in all other groups. Rats in LIRI group were intraperitoneally injected with an equal amount of physiological saline 15 minutes before constructing LIRI model； rats in Control group were intraperitoneally injected with an equal amount of physiological saline 15 minutes before freeing left pulmonary hilum； rats in other groups were intraperitoneally injected with corresponding dose of drug 15 minutes before constructing LIRI model. The wet/dry weight ratio of lungs was calculated. HE staining was used to study lung tissue pathology. Immunofluorescence staining was used to detect the relative fluorescence intensity of gasdermin D （GSDMD） and NLRP3 double positive cells in lung tissue. ELISA was used to detect interleukin-1β and IL-18 in lung tissue. Western blot was used to detect HIF-1α， NLRP3， cysteine-aspartic protease-1 （Cleaved caspase-1）， and gasdermin D-N （GSDMD-N） proteins in lung tissue. ResultsCompared to the Control group， the LIRI group showed disordered alveolar structure， thickened alveolar septa， and abundant inflammatory cell infiltration in rats. The lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， IL-1β， IL-18 levels， and HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N proteins increased （P0.05）. For the LIRI group， rats in the RMZL low， medium， and high-dose groups displayed attenuated alveolar septal thickening and reduced inflammatory cell infiltration. The lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， IL-1β， IL-18 levels， and HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N proteins declined， and the RMZL high-dose group showed the most prominent trend （P0.05）. Compared with the RMZL high-dose group， rats in the RMZL high-dose+DMOG group exhibited thickened alveolar septa and more inflammatory cell infiltration， along with increased lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， levels of IL-1β and IL-18， and protein expression of HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N （P0.05）. ConclusionRMZL may inhibit pyroptosis in LIRI rats by suppressing HIF-1α/NLRP3 pathway.

Objective To investigate the temporal changes in pathological damage and macrophage polarization in liver and spleen tissues of mice infected with Angiostrongylus cantonensis, and to preliminarily unravel the peripheral immune responses during the early stage of A. cantonensis infection. Methods Forty female BALB/c mice at ages of 6 to 8 weeks were randomly divided into four groups, including the control group and 7-, 14-, and 21-day infection groups, with 10 mice in each group. Each mouse in the infection groups was inoculated with 30 third-stage (L3) larvae of A. cantonensis by oral gavage, and five mice were randomly selected from each infection group on days 7, 14, and 21 post-infection, while mice in the control group were given the same volume of physiological saline and five mice were randomly selected from the control group on the day of oral gavage. Mouse liver and spleen tissues were sampled. The histopathological changes of mouse liver and spleen tissues were observed using hematoxylin and eosin (HE) staining, and the percentage of positive staining area and the co-localization positive rates of the macrophage surface antigens F4/80, CD86, and CD206 were quantified in mouse liver and spleen tissues using immunohistochemical and immunofluorescence staining. In addition, five mice were collected from each infection group on days 7, 14, and 21 post-infection, and five mice were collected from the control group on the day of oral gavage. Mouse liver and spleen tissues were sampled for detection of macrophage markers CD86 and CD206 and macrophage phenotyping using flow cytometry, and the expression of M1 macrophage markers, including inducible nitric oxide synthase (Nos2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and M2 markers, including arginase 1 (Arg1), mannose receptor C-type 1 (Mrc1) and chitinase-like protein 3 (Chil3) was quantified in mouse liver and spleen tissues using real-time quantitative PCR (RT-qPCR) assay. Results Proliferative lesions of the hepatocyte were observed in mouse liver tissues and the follicular structures of the mouse spleen white pulp were disrupted 21 days post-infection with A. cantonensis. Immunohistochemical staining showed that there were significant differences in the percentages of F4/80, CD86 and CD206 positive staining areas in the liver and spleen tissues among the four groups of mice (F = 242.40, 197.14, 183.19, 157.65, 242.35 and 146.24; all P values < 0.001), and the percentages of positive staining in the liver and spleen tissues of mice in the 14-day infection group [(4.45 ± 0.51)%, (3.74 ± 0.67)%, (8.32 ± 0.72)%, (16.56 ± 1.14)%, (11.62 ± 0.52)%, and (8.29 ± 0.72)%, respectively] and the 21-day infection group [(3.70 ± 0.11)%, (3.22 ± 0.43)%, (11.53 ± 1.03)%, (12.59 ± 1.05)%, (9.02 ± 0.83)%, and (11.67 ± 1.10)%, respectively] were higher than in the control group [(0.35 ± 0.16)%, (0.40 ± 0.02)%, (0.93 ± 0.05)%, (2.78 ± 0.26)%, (2.33 ± 0.20)%, and (1.85 ± 0.20)%, respectively] (all P values < 0.05). Immunofluorescence staining showed significant differences in the positive rates of F4/80 co-localization with CD86 and CD206 in mouse liver and spleen tissues among the four groups (F = 24.42, 25.28, 54.51 and 130.55; all P values < 0.001). Flow cytometry detected significant differences in the proportions of CD86⁺ and CD206⁺ macrophages in mouse liver and spleen tissues among the four groups (F = 67.98, 18.41, 29.77, 172.80; all P values < 0.001), and the proportions of CD206⁺ macrophages in the liver and spleen of the 21-day infection group were significantly higher than those in the control group [(9.25 ± 2.55)% vs (3.83 ± 0.72)%, and (4.22 ± 0.56)% vs (0.47 ± 0.18)%, respectively] (both P values < 0.05). In addition, RT-qPCR assay quantified significant differences in the relative mRNA expression of M1 macrophage markers (IL-1β, TNF-α and Nos2) and M2 macrophage markers (Arg1, Chil3 and Mrc1) in mouse liver and spleen tissues among the four groups (F = 41.30, 31.82, 199.33, 19.96, 62.01, 119.76, 23.67, 95.90, 72.27, 82.59, 123.41 and 29.75; all P values < 0.05). Conclusions A. cantonensis infection may cause progressive pathological damage in mouse liver and spleen tissues, accompanied by dynamic temporal changes in macrophage polarization. M1 macrophage polarization predominates at the early stage of A. cantonensis infection and shifts towards M2 polarization at the later stages, suggesting that M2 polarization may participate in immune regulation at late stages of A. cantonensis infection by suppressing excessive inflammatory responses and promoting tissue repair.

Objective: To systematically analyze the revisions content and technological development trends of microbiological standards in the Chinese Pharmacopoeia (ChP) 2025 Edition, and explore its novel requirements in risk-based pharmaceutical product lifecycle management.
Methods: A comprehensive review was conducted on 26 microbiological-related standards to summarize the revision directions and scientific implications from perspectives including the revision overview, international harmonization of microbiological standards, risk-based quality management system, and novel tools and methods with Chinese characteristics.
Results: The ChP 2025 edition demonstrates three prominent features in microbiological-related standards: enhanced international harmonization, introduced emerging molecular biological technologies, and established a risk-based microbiological quality control system.
Conclusion: The new edition of the Pharmacopoeia has systematically constructed a microbiological standard system, which significantly improves the scientificity, standardization and applicability of the standards, providing a crucial support for advancing the microbiological quality control in pharmaceutical industries of China.

Objective:To systematically analyze the revisions content and technological development trends of microbiological standards in the Chinese Pharmacopoeia(ChP)2025 Edition,and explore its novel requirements in risk-based pharmaceutical product lifecycle management.Methods:A comprehensive review was conducted on 26 microbiological-related standards to summarize the revision directions and scientific implications from perspectives including the revision overview,international harmonization of microbiological standards,risk-based quality man-agement system,and novel tools and methods with Chinese characteristics.Results:The ChP 2025 edition demon-strates three prominent features in microbiological-related standards:enhanced international harmonization,intro-duced emerging molecular biological technologies,and established a risk-based microbiological quality control sys-tem.Conclusion:The new edition of the Pharmacopoeia has systematically constructed a microbiological standard system,which significantly improves the scientificity,standardization and applicability of the standards,providing a crucial support for advancing the microbiological quality control in pharmaceutical industries of China.

OBJECTIVE: To explore the clinical and genetic characteristics of a Chinese pedigree affected with Hypertrophic cardiomyopathy (HCM) due to a truncating variant of ALPK3 gene. METHODS: A 44-year-old male admitted to Taizhou Hospital of Zhejiang Province on December 29, 2018 was selected as the study subject. Whole-exome sequencing (WES) was carried out, and candidate variant was interpreted by following the guidelines from the American College of Medical Genetics and Genomics (ACMG). For ALPK3 was considered an autosomal recessive gene, the WES results was considered insufficient to explain his phenotype. In April 2023, the proband's WES data were re-analyzed using updated annotation pipelines, and peripheral blood samples were collected from his first-degree relatives (mother and brother) for Sanger sequencing validation. Conservation analysis and protein structural modeling were performed to assess the impact of the variant. Clinical evaluation and genetic counseling were provided to the proband's family members. Relevant literature on ALPK3tv-induced HCM patients were searched in Wanfang Data Knowledge Service Platform, CNKI, and PubMed database using "ALPK3" and "hypertrophic cardiomyopathy" as keywords. Clinical characteristics of HCM patients with heterozygous ALPK3tv variants were summarized and compared with the clinical characteristics of HCM patients with positive sarcomere-associated gene variants (SARC+). This study was approved by the Medical Ethics Committee of Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University (Ethics No.: K20230314). RESULTS: The proband was a 44-year-old male who was transferred to our institution on December 29, 2018 due to "chest tightness and pain for 6 months, exacerbated for 2 days". Emergency coronary angiography was performed, which led to a preliminary diagnosis of "acute coronary syndrome", and the patient was admitted to the Cardiology Department for treatment. Based on electrocardiogram and echocardiogram findings, the diagnosis was revised as HCM. The patient's condition has stabilized post-coronary angiography, and he was discharged with improved condition. On January 2019, WES was conducted to determine the etiology of the proband's HCM. WES results identified a novel heterozygous c.2156dupC (p.Pro720ThrfsTer53) truncating variant in the ALPK3 gene. At that time, the inheritance pattern could not explain the phenotype. In 2022, a literature indicated that heterozygous ALPK3tv could lead to autosomal dominant HCM. Consequently, in April 2023, the proband's whole-exome data were re-annotated, revealing changes in the transcript and protein versions, with the updated site annotated as ALPK3 (NM_020778.5): c.1550dupC (p.Pro518ThrfsTer53). Sanger sequencing confirmed that the proband's mother and brother also carried this variant. The mother exhibited obstructive HCM, while the brother showed no related phenotype. Bioinformatics analysis demonstrated conservation of this site across multiple species, and the variant has resulted in the loss of a protein domain. Based on ACMG guidelines, the variant was classified as likely pathogenic. Literature review and Bayesian calculation further elevated the pathogenicity rating, indicating that this variant was the cause of HCM in the patient. Literature study revealed distinctions between HCM caused by this variant type and SARC+ HCM. The age of onset among heterozygous ALPK3tv patients was delayed by approximately 10 years compared to SARC+ patients. Both forms of HCM exhibited a male predominance, which was particularly marked in individuals with ALPK3tv. Electrocardiographic left ventricular hypertrophy was more prevalent in heterozygous ALPK3tv patients than in SARC+ patients. The incidence of apical or concentric hypertrophy patterns was higher in heterozygous ALPK3tv patients compared to asymmetric septal hypertrophy, which predominated in SARC+ patients. ALPK3tv patients exhibited lower penetrance and later onset compared to SARC+ patients. A positive correlation between left ventricular wall thickness and age was noted in female patients only. CONCLUSION In this pedigree, the proband has presented with HCM, characterized by echocardiographic evidence of apical left ventricular hypertrophy without significant outflow tract obstruction or extracardiac phenotypes. Although his mother and brother had carried the same heterozygous ALPK3 (NM_020778.5) c.1550dupC (p.Pro518ThrfsTer53), the mother exhibited severe obstructive HCM, while the brother was asymptomatic, suggesting incomplete or age-dependent penetrance within the family. This study has enriched the evidence for the pathogenicity of ALPK3tv among Chinese HCM pedigrees and underscored the importance of periodic literature reviews and genetic re-analysis for unresolved genetic testing results.
Humans ; Male ; Pedigree ; Adult ; Cardiomyopathy, Hypertrophic/genetics* ; Heterozygote ; Asian People/genetics* ; Exome Sequencing ; Mutation ; China ; Female ; East Asian People

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.