OBJECTIVE: To evaluate the dynamic changes of glucocorticoid (GC) dose and the feasibility of GC discontinuation in rheumatoid arthritis (RA) patients under the background of Chinese medicine (CM). METHODS: This multicenter retrospective cohort study included 1,196 RA patients enrolled in the China Rheumatoid Arthritis Registry of Patients with Chinese Medicine (CERTAIN) from September 1, 2019 to December 4, 2023, who initiated GC therapy. Participants were divided into the Western medicine (WM) and integrative medicine (IM, combination of CM and WM) groups based on medication regimen. Follow-up was performed at least every 3 months to assess dynamic changes in GC dose. Changes in GC dose were analyzed by generalized estimator equation, the probability of GC discontinuation was assessed using Kaplan-Meier curve, and predictors of GC discontinuation were analyzed by Cox regression. Patients with <12 months of follow-up were excluded for the sensitivity analysis. RESULTS: Among 1,196 patients (85.4% female; median age 56.4 years), 880 (73.6%) received IM. Over a median 12-month follow-up, 34.3% (410 cases) discontinued GC, with significantly higher rates in the IM group (40.8% vs. 16.1% in WM; P<0.05). GC dose declined progressively, with IM patients demonstrating faster reductions (median 3.75 mg vs. 5.00 mg in WM at 12 months; P<0.05). Multivariate Cox analysis identified age <60 years [P<0.001, hazard ratios (HR)=2.142, 95% confidence interval (CI): 1.523-3.012], IM therapy (P=0.001, HR=2.175, 95% CI: 1.369-3.456), baseline GC dose ⩽7.5 mg (P=0.003, HR=1.637, 95% CI: 1.177-2.275), and absence of non-steroidal anti-inflammatory drugs use (P=0.001, HR=2.546, 95% CI: 1.432-4.527) as significant predictors of GC discontinuation. Sensitivity analysis (545 cases) confirmed these findings. CONCLUSIONS RA patients receiving CM face difficulties in following guideline-recommended GC discontinuation protocols. IM can promote GC discontinuation and is a promising strategy to reduce GC dependency in RA management. (Trial registration: ClinicalTrials.gov, No. NCT05219214).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Arthritis, Rheumatoid/drug therapy* ; Glucocorticoids/therapeutic use* ; Medicine, Chinese Traditional ; Retrospective Studies

ObjectiveTo investigate the mechanism of kidney-tonifying and liver-regulating cyclical therapy and its formula in regulating endometrial receptivity during the "implantation window" in rats with polycystic ovary syndrome （PCOS）. MethodsSix rats were randomly selected from 36 SPF SD female rats as the normal group， and the remaining rats were administered letrozole to induce a PCOS model. By using a random number method， the rats were divided into the following groups： normal group， model group， Xiaoyaosan group （11.97 g·kg^-1）， Sanzi Yangmo decoction group （28.35 g·kg^-1）， cyclical therapy group （11.97/28.35 g·kg^-1）， and aspirin group （8 × 10^-3 mg·kg^-1）. After 12 days of continuous administration by gavage （equivalent to three estrous cycles）， female and male rats were co-housed. On the fifth day of pregnancy， the number of blastocyst implantation in each group was counted. Hematoxylin-eosin （HE） staining was used to observe the pathological morphology of rat endometrial tissue. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of estradiol （E₂） and progesterone （P） in rat serum. Western blot was used to detect the protein expression of vascular endothelial growth factor （VEGF）， progesterone receptor （PR）， estrogen receptor （ER）， androgen receptor （AR）， and integrin（ITG） αvβ3 in rat endometrial blood vessels. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of miR-140-5 P， VEGF， vascular endothelial growth factor receptor 2 （VEGFR2）， PR， ER， AR， and ITGαvβ3 in rat endometrium. ResultsCompared with normal group， the estrous cycle of the rats in model group continued to be in the estrus interval and the estrous cycle lost regular changes. The endometrium was significantly thinner， the number of uterine glands and blood vessels were significantly reduced （P<0.01）， and the pregnancy rate was significantly reduced. Compared with the model group， each drug group restored the regular estrous cycle to varying degrees， and the endometrial thickness and the number of blood vessels were significantly improved （P<0.01）. The pregnancy rate of each drug group increased， and the effect of the cycle therapy group could reach the normal level. The results of molecular biology experiments showed that compared with the normal group， the levels of serum E₂ and P in the model group were significantly decreased （P<0.01）， the expression of VEGF， ER， PR and ITGαvβ3 protein was significantly decreased （P<0.05，P<0.01）， the expression of AR protein was significantly increased （P<0.01）， the expression of miR-140-5P and AR mRNA was significantly increased （P<0.01）， and the expression of VEGF， VEGFR2， ER， PR and ITGαvβ3 mRNA was significantly decreased （P<0.01）. Compared with model group， the serum E₂ level in the Xiaoyaosan group was significantly increased （P<0.01）.The levels of E₂ and P in serum of rats in Sanzi Yangmo decoction group， cycle therapy group and aspirin group were significantly increased （P<0.01）. The expression of AR protein in each drug group was significantly decreased （P<0.01）. The expression of VEGF and ITGαvβ3 protein in Xiaoyaosan group was significantly increased （P<0.01）. The expression of VEGF， ER and PR protein in Sanzi Yangmo decoction group was increased to varying degrees （P<0.05，P<0.01）. The expression of VEGF， PR， ER and ITGαvβ3 protein in the cycle therapy group and the aspirin group increased to varying degrees （P<0.05，P<0.01）. The expression of miR-140-5P and AR mRNA in each drug group was significantly decreased （P<0.01）. The expression of VEGF， VEGFR2， ER， PR and ITGαvβ3 mRNA in each drug group increased to varying degrees （P<0.05，P<0.01）. Compared with Xiaoyaosan group and Sanzi Yangmo decoction group， the expression of miR-140-5P， VEGFR2， ER， PR， AR and ITGαvβ3 mRNA in the cycle therapy group were significantly different （P<0.05，P<0.01）. ConclusionThe kidney-tonifying and liver-regulating cyclical therapy may reduce the activity of miR-140-5P， target the upregulation of VEGF expression， mediate angiogenesis， and promote endometrial angiogenesis， thereby playing a synergistic role in improving endometrial receptivity in PCOS-induced infertility. Its efficacy in increasing pregnancy rates surpasses that of Xiaoyaosan or Sanzi Yangmo decoction used alone.

ObjectiveTo investigate the mechanism of kidney-tonifying and liver-regulating cyclical therapy and its formula in regulating endometrial receptivity during the "implantation window" in rats with polycystic ovary syndrome （PCOS）. MethodsSix rats were randomly selected from 36 SPF SD female rats as the normal group， and the remaining rats were administered letrozole to induce a PCOS model. By using a random number method， the rats were divided into the following groups： normal group， model group， Xiaoyaosan group （11.97 g·kg^-1）， Sanzi Yangmo decoction group （28.35 g·kg^-1）， cyclical therapy group （11.97/28.35 g·kg^-1）， and aspirin group （8 × 10^-3 mg·kg^-1）. After 12 days of continuous administration by gavage （equivalent to three estrous cycles）， female and male rats were co-housed. On the fifth day of pregnancy， the number of blastocyst implantation in each group was counted. Hematoxylin-eosin （HE） staining was used to observe the pathological morphology of rat endometrial tissue. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of estradiol （E₂） and progesterone （P） in rat serum. Western blot was used to detect the protein expression of vascular endothelial growth factor （VEGF）， progesterone receptor （PR）， estrogen receptor （ER）， androgen receptor （AR）， and integrin（ITG） αvβ3 in rat endometrial blood vessels. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of miR-140-5 P， VEGF， vascular endothelial growth factor receptor 2 （VEGFR2）， PR， ER， AR， and ITGαvβ3 in rat endometrium. ResultsCompared with normal group， the estrous cycle of the rats in model group continued to be in the estrus interval and the estrous cycle lost regular changes. The endometrium was significantly thinner， the number of uterine glands and blood vessels were significantly reduced （P<0.01）， and the pregnancy rate was significantly reduced. Compared with the model group， each drug group restored the regular estrous cycle to varying degrees， and the endometrial thickness and the number of blood vessels were significantly improved （P<0.01）. The pregnancy rate of each drug group increased， and the effect of the cycle therapy group could reach the normal level. The results of molecular biology experiments showed that compared with the normal group， the levels of serum E₂ and P in the model group were significantly decreased （P<0.01）， the expression of VEGF， ER， PR and ITGαvβ3 protein was significantly decreased （P<0.05，P<0.01）， the expression of AR protein was significantly increased （P<0.01）， the expression of miR-140-5P and AR mRNA was significantly increased （P<0.01）， and the expression of VEGF， VEGFR2， ER， PR and ITGαvβ3 mRNA was significantly decreased （P<0.01）. Compared with model group， the serum E₂ level in the Xiaoyaosan group was significantly increased （P<0.01）.The levels of E₂ and P in serum of rats in Sanzi Yangmo decoction group， cycle therapy group and aspirin group were significantly increased （P<0.01）. The expression of AR protein in each drug group was significantly decreased （P<0.01）. The expression of VEGF and ITGαvβ3 protein in Xiaoyaosan group was significantly increased （P<0.01）. The expression of VEGF， ER and PR protein in Sanzi Yangmo decoction group was increased to varying degrees （P<0.05，P<0.01）. The expression of VEGF， PR， ER and ITGαvβ3 protein in the cycle therapy group and the aspirin group increased to varying degrees （P<0.05，P<0.01）. The expression of miR-140-5P and AR mRNA in each drug group was significantly decreased （P<0.01）. The expression of VEGF， VEGFR2， ER， PR and ITGαvβ3 mRNA in each drug group increased to varying degrees （P<0.05，P<0.01）. Compared with Xiaoyaosan group and Sanzi Yangmo decoction group， the expression of miR-140-5P， VEGFR2， ER， PR， AR and ITGαvβ3 mRNA in the cycle therapy group were significantly different （P<0.05，P<0.01）. ConclusionThe kidney-tonifying and liver-regulating cyclical therapy may reduce the activity of miR-140-5P， target the upregulation of VEGF expression， mediate angiogenesis， and promote endometrial angiogenesis， thereby playing a synergistic role in improving endometrial receptivity in PCOS-induced infertility. Its efficacy in increasing pregnancy rates surpasses that of Xiaoyaosan or Sanzi Yangmo decoction used alone.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective To investigate disease characteristics and hospitalization costs of children with Mycoplasma Pneumoniae pneumonia(MPP)admitted to Shanghai municipal medical hospitals from 2019 to 2023.Methods Depending on the Shanghai Municipal Hospital Pediatric Alliance,we retrospectively investigated community acquired MPP pediatric patients hospitalized in 22 municipal hospitals with pediatric qualifications(including 4 children's hospitals)in Shanghai from Jan 2019 to Dec 2023.We collected the patients'diagnosis codes,gender,age,length of hospital stay,hospitalization costs,and whether they progressed to severe Mycoplasma pneumoniae pneumonia(SMPP).Results From 2019 to 2023,a total of 29 045 hospitalized children with MPP were treated,with 6 035 cases(20.8%)identified as SMPP in the 22 hospitals.Trend analysis revealed a rising trend with years in the proportion of SMPP patients(χ2trend=365.498,P<0.001).Among the 4 children's hospitals,there were 18 710 cases with MPP,including 4 078 cases(21.8%)of SMPP.The proportion of SMPP patients also showed an increasing trend with years(χ2trend=14.548,P<0.001),and the proportion in 2023(23.0%)was higher than that in previous years with statistical significance.There were statistical differences in the seasonal distribution of MPP cases between different years,with higher proportions in summer and autumn overall.The age distribution of hospitalized MPP children varied among different years,with school-age children accounting for the majority(56.8%)in 2023.There was no difference in the distribution of severe cases between different genders,but there were differences in the proportion of severe cases among different age groups in different years,with a gradual increase in severe cases among children aged 1 to 3 years(χ2trend=191.567,P<0.001).The average length of hospital stay for MPP during the epidemic was higher than that during non-epidemic periods,and there were statistically significant differences in the average length of hospital stay between different years(P<0.001).The individual hospitalization costs during the epidemic were higher than in other years,and there were statistically significant differences in individual hospitalization costs between different years(P<0.001).The total hospitalization costs were still higher in 2019 and 2023.The individual hospitalization costs for SMPP were higher than for non-SMPP cases.Conclusion MPP outbreaks occurred in Shanghai in 2019 and 2023,with the higher proportions in summer and autumn overall.Compared to previous years,the number of hospitalized MPP children in Shanghai was higher in 2023,with a higher proportion of SMPP cases,especially among children under 3 years old.The individual per capita hospitalization expenses for SMPP cases were higher than for non-SMPP cases.

Aim To investigate the intracellular up-take and target protein binding characteristics of two Bruton's tyrosine kinase inhibitors(BTKi)with differ-ent selectivities to provide further insights into the mechanisms of drug off-target-related bleeding risk.Methods Ibrutinib(non-selective BTKi)and za-nubrutinib(selective BTKi)were used as study drugs.After incubation of MEC-1 cells and human platelets with drugs,the cellular thermal shift assay(CETSA)was combined with Western blot to obtain the melting curve and isothermal curve to analyze the binding char-acteristics of the two drugs with the target protein BTK.After incubation of MEC-1 cells and human platelets with drugs,the concentrations of the two drugs were detected by liquid chromatography-tandem mass spectrometry(LC-MS/MS)to analyze the intracellular uptake of the two drugs.Results CETSA analysis confirmed that zanubrutinib was more selective for the target protein BTK compared to ibrutinib.LC-MS/MS analysis showed that both drugs were uptaken intracel-lularly by MEC-1 cells and platelets in a concentration-dependent manner.Conclusions While BTKi targe-ting BTK to B lymphocytes exerts therapeutic effects,off-target effects on platelets due to differences in their intracellular uptake,and target-binding characteristics may be one of the reasons for the differences in bleed-ing risk across selective BTKi.

Objective To establish a high performance liquid chromatography(HPLC)aging characteristic chromatogram of Guangdong Citri Reticulatae Pericarpium.Methods HPLC-diode array detector(DAD)was used to analyze the composition differences between different years of Guangdong Citri Reticulatae Pericarpium,and the relative peak area of each differential chromatographic peak was determined.The aging grade was classified by cluster analysis,and evaluated by the similarity evaluation system for chromatographic fingerprint of TCM(2012A edition).Results The different years of Guangdong Citri Reticulatae Pericarpium was clustered into two different aging grades of classⅠ and class Ⅱ.The similarity of class Ⅰ(low aging grade)Guangdong Citri Reticulatae Pericarpium was 0.708-0.957,and the similarity of class Ⅱ(high aging grade)Guangdong Citri Reticulatae Pericarpium was 0.734-0.976,and the similarity between the two was lower than 0.6.There were 9 different chromatographic peaks in the established characteristic chromatogram.The control characteristic spectrum T2 of typeⅡ Guangdong Citri Reticulatae Pericarpium can be regarded as its aging characteristic spectrum,among which peaks 1-4 and 9 are aging characteristic peaks.Conclusion The established aging characteristic chromatogram of Guangdong Citri Reticulatae Pericarpium is simple in operation,with good repeatability and reliability,and can be used for quality evaluation of different years of Guangdong Citri Reticulatae Pericarpium.