In this study, we constructed a GLP-2R-HEK293 cell line and established a method for the determination of the in vitro biological activity of teduglutide based on HTRF, after optimizing experimental conditions and methodological verification. We also carried out relative potency detection of teduglutide pharmaceutical products using this method. The result showed that there was a quantitative-efficient relationship between the teduglutide activity and cAMP contents in GLP-2R-HEK293 cells, which conformed to four-parameter model. Method verification results of five concentrations of teduglutide (64%, 80%, 100%, 125% and 156%) met the requirements of the General Rules of Chinese Pharmacopoeia, 2020 edition, Volume IV (9401). We then analyzed the relative potency of three batches of teduglutide drug substances and three batches of drug products. The linearity, regression and parallelism of the obtained curves all fit the system suitability requirements. The relative potency of six batches of teduglutide was from 83% to 105%. In summary, the biological activity detection method established in this study was accurate, precise, simple and time-saving, which can be used for quality control of teduglutide pharmaceutical products.

This study constructed a LHCGR-CRE-luc-HEK293 transgenic cell line according to the activation of the cAMP signaling pathway after recombinant human chorionic gonadotropin binding to the receptor. The biological activity of recombinant human chorionic gonadotropin was assayed using a luciferase assay system. The relative potency of the samples was calculated using four-parameter model. And the method conditions were optimized to validate the specificity, relative accuracy, precision and linearity of the method. The results showed that there was a quantitative potency relationship of human chorinonic gonadotropin (hCG) in the method and it was in accordance with the four-parameter curve. After optimization, the conditions were determined as hCG dilution concentration of 2.5 μg·mL^-1, dilution ratio of 1∶4, cell number of 10 000-15 000 cells/well, and induction time of 6 h. The method had good specificity, relative accuracy with relative bias ranging from -8.9% to 3.4%, linear regression equation correlation coefficient of 0.996, intermediate precision geometric coefficient of variation ranging from 3.3% to 15.0%, and linearity range of 50% to 200%. This study successfully established and validated a reporter gene method to detect hCG biological activity, which can be used for hCG biological activity assay and quality control.

Objective:To investigate the expression of soluble lectin-like oxidized low den-sity lipoprotein receptor-1(sLOX-1)and C1q/tumor necrosis factor related protein 3(CTRP3)in the serum of patients with lower extremity arteriosclerosis obliterans(ASO)and their relationship with restenosis(ISR)after stent intervention.Methods:From June 2019 to June 2022,106 ASO pa-tients who underwent stent intervention in our hospital were regarded as the study subjects.One year after surgery,they were separated into a non ISR group(n=64)and an ISR group(n=42)based on their onset of ISR.The serum levels of sLOX-1 and CTRP3 were compared between the two groups;multivariate Logistic regression was applied to analyze the influencing factors of ISR after stent intervention in ASO patients;ROC curve was applied to analyze the predictive value of se-rum sLOX-1 and CTRP3 levels for ISR after stent intervention in ASO patients.Results:The se-rum sLOX-1 level in the ISR group was obviously higher than that in the non ISR group(P＜0.05),and the CTRP31 level was obviously lower than that in the non ISR group(P＜0.05).The complete occlusion,and sLOX-1 were independent risk factors for ISR after stent intervention in ASO pa-tients,while CTRP3 was a protective factor for ISR after stent intervention in ASO patients(P＜0.05).The AUC of the combination of serum sLOX-1 and CTRP3 in predicting ISR after stent in-tervention in ASO patients was 0.944,with a sensitivity of 97.62％and a specificity of 79.69％,which was superior to the individual predictions of sLOX-1 and CTRP3(Zcombineddetaction-sLOX-1=2.732,Zcombineddetection-CTRP3=2.143,P=0.006,0.032).Conclusion:After ASO stent intervention,the serum level of sLOX-1 was obviously increased in ISR patients,while the level of CTRP3 was obviously reduced,and the combination of the two fatcors has high predictive value for the occurrence of ISR in ASO patients after stent intervention.

Objective To investigate the effects of α7 nicotinic acetylcholine receptor(nAChR)agonist on β3-adrenoceptor agonist-induced impairment of white fat homeostasis and beige adipose formation and heat production in obese mice.Methods Forty obese C57BL/6J mice were randomized into high-fat feeding group,β3-adrenoceptor agonist-treated model group,α7 nAChR agonist group,and α7 nAChR inhibitor group(n=10),with another 10 mice with normal feeding as the blank control group.White adipose tissue from the epididymis of the mice were sampled for HE staining of the adipocytes.The expression levels of TNF-α,IL-1β,IL-10 and TGF-β in the white adipose tissue were determined by ELISA,and the mRNA levels of iNOS,Arg1,UCP-1,PRDM-16 and PGC-1α were detected using RT-qPCR.Western blotting was performed to detect the expression levels of NF-κB P65,p-JAK2,p-STAT3 in the white adipose tissue.Results Compared with those in the blank control group,the mice with high-fat feeding showed significantly increased body weight,more fat vacuoles in the white adipose tissue,increased volume of lipid droplets in the adipocytes,upregulated iNOS mRNA expression and protein expression of TNF-α and IL-1β,and lowered expression of Arg-1 mRNA and IL-10 and TGF-β proteins(P<0.01).Treatment with α7 nAChR significantly reduced mRNA levels of PRDM-16,PGC-1α and UCP-1,lowered TNF-α and IL-1β expressions,increased IL-10 and TGF-β expressions,and reduced M1/M2 macrophage ratio in the white adipose tissues(P<0.05 or 0.01).Conclusion Activation of α7 nAchR improves white adipose tissue homeostasis impairment induced by β3 agonist,promotes transformation of M1 to M2 macrophages,reduces inflammatory response in white adipose tissue,and promote beige adipogenesis and thermogenesis in obese mice.

Objective To investigate the imaging features of ultrasound,CT and air enema in children with intestinal duplications,and to improve the preoperative diagnosis rate.Methods The imaging data of 22 cases with intestinal duplications confirmed by operation and pathology were analyzed retrospectively.Results Fifteen cases underwent ultrasound,in which 12 cases showed cystic lesions,and the cyst wall showed typical"double ring sign"and"Y sign".12 cases underwent enhanced CT examination,in which 11 cases showed cystic lesions,and the enhancement pattern of the cyst wall was similar to that of intestinal wall.8 cases underwent CT plain scan examination,but only 3 cases showed cystic lesions and no characteristic signs were found.3 patients of secondary intussusceptions underwent air enema,in which 1 case of recurrent intussusceptions was unsuccessful,and 2 cases still showed masses in the ileocecal region after successful reduction.Conclusion CT plain scan has low diagnostic value for intestinal duplications in children,and the combination of ultrasound and CT enhanced examination can improve the preoperative diagnosis rate.For patients with recurrent intussusceptions and successful air enema reductions,if masses are still seen in the ileocecal region,the possibility of intestinal duplications should be considered.

Objective:To establish a microwave digestion and inductively coupled plasma mass spectrometry(ICP-MS)for determination on calcium content of Xiao'er Magan granules and discuss the effect of decocting gypsum into medicine on calcium content.Methods:ICP-MS was adopted to determine the calcium content in the preparation,and the difference of calcium content in the small preparation and Xiao'er Magan granules prepared by different pul-verization degree gypsum and different alcohol precipitation processes were compared.Results:The consistency of calcium content between different enterprises and batches of the same enterprise was poor.The results showed that the larger the particles,the lower the calcium transfer rate.The smaller the particles,the higher the calcium trans-fer rate.Conclusion:The transfer rate of gypsum decocted calcium is related to its degree of comminution to ensure consistency of preparation quality.It is suggested to unify the comminution degree of gypsum.The method can pro-vide guidance for the optimization on preparation technology of Xiao'er Magan granules.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.