ObjectiveTo explore the mechanism through which Gantou Fumu decoction （GDFMT）-containing serum inhibits the activation of hepatic stellate cells. MethodsSerum pharmacology techniques were employed to prepare GDFMT-containing serum samples. Rat hepatic stellate cells （HSCT6） were randomly allocated into three groups： Control， penicillamine （90 mg·kg^-1）， and GDFMT （6.8 g·kg^-1）. Cell viability was assessed by the cell counting kti-8 （CCK-8） assay， intracellular ROS levels were determined by flow cytometry using the DCFH‑DA fluorescent probe and while extracellular collagen Ⅰ （ColⅠ） levels were quantified via enzyme linked immunosorbent assay （ELISA）. Intracellular α-smooth muscle actin （α-SMA） expression was visualized through immunofluorescence staining. Real-time polymerase chain reaction（Real-time PCR） and Western blot were performed to evaluate alterations in the expression of nuclear factor-erythroid 2-related factor 2 （Nrf2）， glutamate cysteine ligase， catalytic （GCLC）， glutamate-cysteine ligase， modifier subunit （GCLM）， Kelch-like ECH-associated protein 1 （Keap1）， NAD（P）H：Quinone oxidoreductase 1 （NQO1）， and heme oxygenase-1 （HO-1）. Genetic knockdown of Nrf2 was achieved through small interfering （siRNA） transfection to validate pathway specificity. ResultsCCK-8 data indicated that under the selected experimental conditions， culturing HSCT6 cells with 10% （volume fraction） GDFMT-containing serum for 48 h demonstrated equivalent effect in inhibiting HSCT6 cell proliferation compared with culturing HSCT6 cells with 10% （volume fraction） penicillamine-containing serum for 36 h， with no statistically significant difference between the two groups. After treatment of HSCT6 cells with siRNA-mediated Nrf2 gene transfection technique， the inhibitory effect of GDFMT on the activation process of HSCT6 cells was significantly weakened. After HSCT6 cells were cultured with GDFMT-containing serum for 48 h， the flow cytometry with a fluorescence probe showed that the content of reactive oxygen species （ROS） in the cells was significantly reduced. After the expression level of the Nrf2 gene in HSCT6 cells was knocked down by siRNA transfection， the content of ROS increased （P<0.01）， indicating that GDFMT significantly reduced the ROS level in activated HSCT6 cells， and this effect strictly depended on the integrity of the Nrf2 pathway. Quantitative analysis by ELISA showed that the synthesis of ColⅠ in the HSCT6 cell culture system treated with GDFMT-containing serum for 48 h was lower than that in the control group （P<0.01）. After the Nrf2 gene level of HSCT6 cells was knocked down by siRNA transfection， the ColⅠ concentration in the culture supernatant increased （P<0.01）. The results of α-SMA detection by IF method showed that compared with the normal group， GDFMT-containing serum reduced the expression of α-SMA （P<0.01） and the protein level of α-SMA in HSCT6 cells was increased （P<0.01） after siRNA-mediated Nrf2 silencing， suggesting that Nrf2 signaling pathway may be involved in regulating the phenotypic transformation process of the cells. Real-time PCR and Western blot results showed that GDFMT-containing serum reduced the protein level of α-SMA （P<0.01） and enhanced the gene and protein levels of Nrf2 in the nucleus and GCLC， HO-1， Keap1， GCLM， and NQO1 in the cytoplasm of HSCT6 cells （P<0.05， P<0.01）. After the Nrf2 gene level of HSCT6 cells was knocked down by siRNA transfection， the protein level of α-SMA was increased （P<0.01）， and the levels of GCLC， GCLM， Keap1， NQO1， and HO-1 were decreased （P<0.05， P<0.01）. These results indicated that GDFMT-containing serum successfully triggered the Nrf2 signaling pathway of HSCT6 cells. ConclusionThe anti-hepatic fibrosis effect of 10%GDFMT was equivalent to that of penicillamine. In addition， GDFMT can inhibit HSC activation and reduce oxidative stress damage by activating the Nrf2/antioxidant response element （ARE） pathway， as manifested by the up-regulated expression of Nrf2 and downstream antioxidant genes （GCLC， GCLM， HO-1， Keap1， and NQO1） and reduced secretion of ROS， α-SMA， and ColⅠ.

Objective:To compare the effects of manual acupuncture(MA),electroacupuncture(EA),and moxibustion on knee joint cartilage morphology,serum inflammatory factors interleukin(IL)-6 and IL-10,matrix metalloproteinase 13(MMP13),and intestinal flora composition in knee osteoarthritis(KOA)model rats.Methods:Forty male specific-pathogen-free Sprague-Dawley rats aged seven weeks were randomly divided into a normal group(n=8)and a KOA modeling group(n=32).The KOA model was established using sodium iodoacetate induction.The KOA modeling rats were further randomly divided into a model group,an MA group,an EA group,and a moxibustion group,with 8 rats in each group.In the MA,EA,and moxibustion groups,interventions targeting the right Futu(ST32)and Zusanli(ST36)were performed for 15 min,once every other day,for 14 sessions.The normal and model groups were bundled on the self-made fixation frame for 15 min.The rat knee joint diameter was measured on the 8th day of adaptive feeding,after successful modeling,and after the 14th intervention.Lequesne behavioral scoring was performed after successful modeling and after the 14th intervention.After the 14th intervention,hematoxylin-eosin(HE)staining and Masson staining were performed with the cartilage sections of the right knee joint.The pathomorphological changes of the rat joint cartilage were observed and quantified by Mankin's score.Enzyme-linked immunosorbent assay was used to detect the rat serum levels of IL-6,IL-10,and MMP13.Additionally,16S rDNA sequencing was used to detect the composition of rat fecal flora.Results:Compared to the normal group,the right knee joint diameter and the Lequesne score were significantly increased in the model group(P<0.01).Compared to the model group,the right knee joint diameter and the Lequesne score of rats in the MA,EA,and moxibustion groups were significantly reduced(P<0.01),with no significant differences among the three intervention groups(P>0.05).HE staining and Masson staining revealed disordered cartilage structure in the model group,which was improved following interventions in the MA group,EA group,and moxibustion group.Mankin's score was significantly higher in the model group versus the normal group(P<0.05)while significantly lower in the MA,EA,and moxibustion groups versus the model group(P<0.05).Serum analysis showed elevated IL-6 and MMP13 levels and reduced IL-10 level in the model group versus the normal group(P<0.05).Compared to the model group,the serum IL-6 level was significantly reduced(P<0.05),and the IL-10 level was significantly increased(P<0.05)in the MA,EA,and moxibustion groups,but without statistical differences among the three intervention groups(P>0.05);moreover,the MMP13 level in the moxibustion group was significantly lower than that in the model group(P<0.05).The alpha diversity analysis of intestinal flora showed no statistical difference in the number of operational taxonomic units(OTUs)and alpha diversity index among groups(P>0.05).Intestinal flora beta diversity analysis revealed significant differences among groups(P<0.05).Intestinal flora composition analysis showed significantly increased relative abundance of Lactobacillus(P<0.05)and significantly decreased relative abundance of Eubacterium_coprostanoligenes(P<0.05)in the model group compared to the normal group;compared to the model group,the relative abundances of Firmicutes,Lactobacillus,and Romboutsia in the MA,EA,and moxibustion groups were significantly reduced(P<0.05);the relative abundance of Bacteroidetes and Lachnospiraceae_NK4A136 in the MA group increased significantly(P<0.05);Bacteroidetes and Ruminococcaceaae_UGC-005 increased significantly in the moxibustion group(P<0.05).Conclusion:MA,EA,and moxibustion effectively reduced knee joint swelling,improved cartilage tissue morphology,optimized intestinal flora composition,down-regulated expression levels of serum pro-inflammatory factors IL-6 and MMP13,and increased expression level of anti-inflammatory factor IL-10 in KOA rats.Among them,moxibustion exhibited the most obvious regulatory effect on inflammatory factors.

Objective To investigate the potential mechanism of miR-21-5p in alleviating cerebral ischemia-reperfusion injury by targeting STAT3.Methods The HT22 cells were induced by OGD/R to construct a cell model of cerebral ischemia reperfusion injury.The expression of miR-21-5p was detected by RT-qPCR.The CCK-8 assay,TUNEL staining and flow cytometry were respectively used to detect the cell viability and apoptosis.ELISA assay was used to determine the contents of inflammatory factors IL-6,IL-10 and TNF-α in the cell supernatant.Western blot was used to detect the expression levels of p-STAT3/STAT3,Cleaved-Caspase-3,Bax and Bcl-2 proteins.The TargetScan database was used to predict the binding sites of miR-21-5p and STAT3.The dual-luciferase reporter gene assay was used to verify the targeting relationship between miR-21-5p and STAT3.Results The relative expression level of miR-21-5p was down-regulated in HT22 cells which induced by OGD/R(P<0.001).The cell viability(P<0.0001)was decreased and the apoptosis rate(P<0.001)was increased in OGD/R induced-HT22 cells.The contents of pro-inflammatory factors IL-6(P<0.001)and TNF-α(P<0.001)was increased,while the content of anti-inflammatory factor IL-10(P<0.001)decreased.After transfection with miR-21-5p mimic,cell viability was enhanced,apoptosis rate was reduced and neuroinflammation was inhibited.MiR-21-5p could target and bind to STAT3.After miR-21-5p inhibitor transfection,cell viability decreased,apoptosis was promoted,and neuroinflammation occurred;STAT3 inhibitor Stattic could reverse the effect of miR-21-5p inhibitor.Conclusion MiR-21-5p could specifically bind to STAT3 and reduce the neuroinflammation and apoptosis of OGD/R induced-HT22 cells.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Nasopharyngeal carcinoma is rare in children and adolescents, but the prognosis is relatively good. More and more studies focus on the growth and development, as well as the quality of life of patients after treatment. Certain progress has been made in the research of nasopharyngeal carcinoma in children and adolescents, covering multiple aspects such as etiology, clinical characteristics, treatment regimens and prognosis. The factors causing nasopharyngeal carcinoma include viral infection, genetic susceptibility and environmental factors, etc. The main treatment methods are radiotherapy, chemotherapy, targeted therapy, immunotherapy and surgery. In addition, traditional Chinese medicine has also shown its unique efficacy and potential in the adjuvant therapy of nasopharyngeal carcinoma, providing more treatment options for patients. Further exploration of the factors influencing the occurrence of nasopharyngeal carcinoma in children and adolescents, and analysis of the effects and applications of different treatment methods, can provide new perspectives and references for future research.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

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.