Objective To establish an ultra-high performance liquid phase tandem triple quadrupole mass spectrometry method for the determination of L-synephrine in rat plasma and to study its pharmacokinetics.Methods The plasma samples were precipitated by acetonitrile vortex,centrifuged,dried by nitrogen,dissolved by mobile phase,and then analyzed.Chromatographic column:Shiseido CAPCELL PAK CR(1∶4)column(2.0 mm × 150.0 mm,5 μm),temperature:25 ℃.Mobile phase:Acetonitrile:0.1％formic acid solution(containing 10 mmoL·L-1 ammonium formate)(73∶27)with flow rate:0.3 mL·min-1 and injection volume was 2 μL.The electrospray ion source ionization and positive ion multiple reaction monitoring mode were used for mass spectrometry detection,and biological sample methodology verification was carried out according to requirements.After intragastric administration with 5 mg·kg-1 dose of L-synephrine,blood samples were collected at different time points to investigate the pharmacokinetic characteristics of L-synephrine in rats.Results L-synephrine showed a good linear relationship in the range of 2-800 ng·mL-1,the lowest limit of quantification of L-synephrine was 2 ng·mL-1.Precision,extraction recovery,matrix effect,accuracy,dilution effect and residual effect all meet the requirements all met the requirements.The main pharmacokinetic parameters:Cmax were(464.83±76.68)ng·L-1,tmax were(0.67±0.26)h,t1/2z were(1.89±0.48)h,AUC0-t were(602.26±42.25)ng·mL-1·h-1,AUC0-∞ were(612.28±41.18)ng·mL-1·h-1.Conclusion The established ultra high performance liquid chromatography-tandem triple quadrupole mass spectrometry method for the determination of L-synephrine in rat plasma is simple and rapid,and can be used for the determination of L-synephrine in plasma.

Objective To investigate the nutritional status of children with Crohn's Disease (CD) at diagnosis and its association with clinical characteristics. Methods A retrospective analysis was performed for the clinical data and nutritional status of 118 children with CD who were admitted to Beijing Children's Hospital,Capital Medical University,from January 2016 to January 2024. A multivariate logistic regression analysis was used to investigate the risk factors for malnutrition. Results A total of 118 children with CD were included,among whom there were 68 boys (57.6％) and 50 girls (42.4％),with a mean age of (11±4) years. Clinical symptoms mainly included recurrent abdominal pain (73.7％,87/118),diarrhea (37.3％,44/118),and hematochezia (32.2％,38/118),and 63.6％ (75/118) of the children had weight loss at diagnosis. The incidence rate of malnutrition was 63.6％ (75/118),and the children with moderate or severe malnutrition accounted for 67％ (50/75). There were 50 children (42.4％) with emaciation,8 (6.8％) with growth retardation,and 9 (7.6％) with overweight or obesity. Measurement of nutritional indices showed a reduction in serum albumin in 83 children (70.3％),anemia in 74 children (62.7％),and a reduction in 25 hydroxyvitamin D in 15 children (60％,15/25). The children with malnutrition had significantly higher disease activity,proportion of children with intestinal stenosis,and erythrocyte sedimentation rate and a significant reduction in serum albumin (P<0.05). The multivariate logistic regression analysis showed that intestinal stenosis was an independent risk factor for malnutrition in children with CD (OR=4.416,P<0.05). Conclusions There is a high incidence rate of malnutrition in children with CD at diagnosis,which is associated with disease activity and disease behavior. The nutritional status of children with CD should be closely monitored.

Objective To understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7％)Gram-positive bacteria and 99 919(48.3％)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9％)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1％),Staphylococcus aureus(n=17 402,8.4％),Klebsiella pneu-moniae(17 325,8.4％),Pseudomonas aeruginosa(n=4 010,1.9％)and Acinetobacter baumannii(n=3 598,1.7％).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3％in 2015 to 20.7％in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9％-66.8％).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9％-53.9％and 14.2％-19.5％,respectively,both showing an upward trend(both P＜0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6％-5.1％and 3.0％-4.5％,respectively,both showing a downward trend year by year(both P＜0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0％-2.0％and 0.6％-1.1％,respectively;presenting a downward trend(P＜0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4％-13.7％and 4.8％-6.4％,respectively,presenting a downward trend(both P＜0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1％-15.6％and 34.7％-45.7％,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0％-65.4％,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.

Objective To investigate changes in the distribution and antimicrobial resistance of bacteria isolated from cerebrospinal fluid(CSF)specimens in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected according to China Antimicrobial Resistance Surveillance Sys-tem(CARSS)technical scheme.Data of bacteria isolated from CSF specimens and antimicrobial susceptibility tes-ting results were analyzed with WHONET 5.6 and SPSS 20.0 software.Results A total of 11 837 bacterial strains were isolated from CSF specimens from member units of Hunan Province Antimicrobial Resistance Surveillance Sys-tem from 2012 to 2021.The top 5 strains were coagulase-negative Staphylococcus(n=6 397,54.0％),Acineto-bacter baumannii(n=764,6.5％),Staphylococcus aureus(n=606,5.1％),Enterococcus faecium(n=465,3.9％),and Escherichia coli(n=447,3.8％).The detection rates of methicillin-resistant coagulase-negative Staphyloco-ccus(MRCNS)and methicillin-resistant Staphylococcus aureus(MRSA)were 58.9％-66.3％and 34.4％-62.1％,respectively.No Staphylococcus spp.were found to be resistant to vancomycin,linezolid,and teicoplanin.The de-tection rate of Enterococcus faecium was higher than that of Enterococcus faecalis,and the resistance rates of En-terococcus f aecium to penicillin,ampicillin,high concentration streptomycin and levofloxacin were all higher than those of Enterococcus faecalis(all P=0.001).Resistance rate of Streptococcus pneumoniae to penicillin was 85.0％,at a high level.Resistance rate of Escherichia coli to ceftriaxone was＞60％,while resistance rates to enzyme inhibitors and carbapenem antibiotics were low.Resistance rate of Klebsiella pneumoniae to ceftriaxone was＞60％,to en-zyme inhibitors piperacillin/tazobactam and cefoperazone/sulbactam was＞30％,to carbapenem imipenem and me-ropenem was about 30％.Resistance rates of Acinetobacter baumannii to most tested antimicrobial agents were＞60％,to imipenem and meropenem were 59.0％-79.4％,to polymyxin B was low.Conclusion Among the bac-teria isolated from CSF specimens,coagulase-negative Staphylococcus accounts for the largest proportion,and the overall resistance of pathogenic bacteria is relatively serious.Bacterial antimicrobial resistance surveillance is very important for the effective treatment of central nerve system infection.

Objective To investigate the distribution and antimicrobial susceptibility of clinically isolated bacteria from intensive care units(ICUs)in hospitals of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021.Methods According to China Antimicrobial Resistance Surveillance System,data of clinically isolated bacterial strains and antimicrobial susceptibility testing results of bacteria from ICUs reported by all member units of Hunan Province Antimicrobial Resistance Surveillance System were analyzed with WHONET 2022 software.Results From 2012 to 2021,the total number of bacteria isolated from ICUs of member units of the Hunan Province Antimi-crobial Resistance Surveillance System was 5 777-22 369,with Gram-negative bacteria accounting for 76.1％-78.0％annually.Staphylococcus aureus ranked first among isolated Gram-positive bacteria each year.The top 5 bacteria among Gram-negative bacteria were Acinetobacter baumannii,Klebsiella pneumoniae,Escherichia coli,Pseudo-monas aeruginosa,and Stenotrophomonas maltophilia.Detection rate of methicillin-resistant Staphylococcus aureus showed a downward trend year by year.No Staphylococcus spp.were found to be resistant to vancomycin,teico-planin and linezolid.Detection rates of vancomycin-resistant Enterococcus faecalis and vancomycin-resistant Entero-coccus faecium were 0.6-1.1％and 0.6％-2.2％,respectively.Resistance rates of Escherichia coli and Kleb-siella pneumoniae to imipenem were 3.1％-5.7％and 7.7％-20.9％,respectively.Resistance rates of Pseudo-monasaeruginosa and Acinetobacter baumannii to imipenem were 24.6％-40.1％and 76.1％-80.9％,respective-ly.Detection rates of carbapenem-resistant Pseudomonas aeruginosa declined year by year.Acinetobacter baumannii maintained high susceptibility to polymyxin B,with resistance rate＜10％.Conclusion Antimicrobial resistance of bacteria from ICUs is serious.Carbapenem-resistant Enterobacteriales has an upward trend after 2019.It is nece-ssary to strengthen the surveillance of bacterial resistance and carry out multidisciplinary collaboration.

Objective To understand the antimicrobial resistance of clinically isolated Enterococcus spp.in Hunan Province.Methods Surveillance data of Enterococcus spp.resistance from member units of Hunan Provincial Anti-microbial Resistance Surveillance System from 2012 to 2021 were collected.Data were cleaned according to a unified method,and WHONET 5.6 software was adopted for statistical analysis.Results From 2012 to 2021,a total of 110 652 non-repetitive Enterococcus spp.strains were included in the analysis,mainly Enterococcus faecalis and Enterococcus faecium,accounting for 46.9％(n=37 774)and 45.9％(n=36 968),respectively,followed by En-terococcus avium(2.5％,n=1 982),Enterococcus gallinarum(1.8％,n=1 428),and Enterococcus casseliflavus(1.5％,n=1 185).The main specimen sources of Enterococcus spp.was urine(51.8％,n=57 350),followed by secretions(9.6％,n=10 660)and bile(8.5％,n=9 377).From 2012 to 2021,the resistance rates of Enteroco-ccus faecalis to ampicillin,teicoplanin,and vancomycin were 5.5％-12.0％,1.3％-2.0％,and 0.6％-1.4％,respectively.The resistance rates of Enterococcus faecium to ampicillin,teicoplanin,and vancomycin were 69.2％-85.0％,1.5％-2.8％,and 0.7％-2.5％,respectively.Except for linezolid and minocycline,the resistance rates of Enterococcus faecium to tested antimicrobial agents were all higher than those of Enterococcus faecalis.The re-sistance rates of Enterococcus faecalis and Enterococcus faecium to vancomycin decreased from 1.4％and 2.1％in 2012 to 0.6％and 0.7％in 2021,respectively,presenting a decreased trend.Conclusion Clinically isolated En-terococcus spp.maintain high antimicrobial susceptibility to vancomycin and teicoplanin.Resistance rates of Entero-coccus faecalis and Enterococcus faecium to vancomycin present decreased trends.

Objective To analyze the distribution and changing trend of antimicrobial resistance of bacteria isolated from bile from Hunan Province Antimicrobial Resistance Surveillance System.Methods Data of pathogens isolated from bile from Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected.The constituent of bacteria and antimicrobial susceptibility testing results were analyzed by WHONET 5.6 software.Changes in antimicrobial resistance was analyze by trend chi-square test.Results The major pathogenic bacteria isolated from bile were Gram-negative bacteria,accounting for 70.84％.The top three isolated Gram-negative pathogens were Escherichia coli(30.14％),Klebsiella pneumoniae(12.15％),and Pseudomonas aeruginosa(5.18％),and the top two Gram-positive bacteria were Enterococcus faecium(10.34％)and Enterococcus faecalis(9.52％).The resistance rates of Klebsiella pneumoniae and Escherichia coli to imipenem were highest in 2012-2013,being 15.7％and 14.9％,respectively,presenting an downward trend(P＜0.05);resistance rates to piperacillin/tazobactam and cefoperazone/sulbactam were＜24％,presenting an upward trend year by year(P＜0.05);the sus-ceptibility rate to amikacin was＞94％,to levofloxacin and ciprofloxacin was 15.5％-65.2％.The highest resis-tance rate of Pseudomonas aeruginosa to imipenem(32.0％)was higher than that of meropenem(22.9％),resis-tance rates to piperacillin/tazobactam and cefoperazone/sulbactam were＜19％.The highest resistance rates of Acinetobacter baumannii to imipenem and meropenem were 59.4％and 62.6％,respectively,resistance rate to cefo-perazone/sulbactam was＜48％,presenting an upward trend(P＜0.05);the highest resistance rate to ciprofloxa-cin(60.8％)was higher than levofloxacin(48.7％);resistance rate to tigecycline was＜8％.The resistance rates of Enterococcus faecium to penicillin and ampicillin were both higher than those of Enterococcus faecalis,presenting an upward trend(P＜0.05).Resistance rate of Enterococcus faecium to vancomycin was lower than that of Entero-coccus faecalis.The resistance rates of Enterococcus faecium to vancomycin and linezolid were 0.5％-4.5％and 0.5％-3.4％,respectively;resistance rates of Enterococcus faecalis to vancomycin and linezolid were 0.2％-1.7％and 0.5％-3.5％,respectively(both P＜0.05),all presenting a downward trend(all P＜0.05).Conclusion Pathogenic bacteria isolated from bile are mainly related to the intestinal flora.The resistance rates of Enterococcus faecalis and Enterococcus faecium to vancomycin and linezolid as well as resistance rate of Enterobacterales to car-bapenem antibiotics all present a downward trend.

Objective To understand the antimicrobial resistance of Escherichia spp.from member units of Hu-nan Province Antimicrobial Resistance Surveillance System from 2012 to 2021.Methods According to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS),data about Escherichia spp.and the anti-microbial susceptibility testing results reported from member units of Hunan Province Antimicrobial Resistance Sur-veillance System were analyzed by WHONET 5.6 software.Results From 2012 to 2021,a total of 476 351 clini-cally isolated Escherichia spp.were collected,475 520 of which were Escherichia coli,accounting for 99.8％;92.6％were isolated from inpatients;39.3％were isolated from urine specimens.Over the past 10 years,the proportion of Escherichia spp.in total detected pathogens remained relatively stable,ranging 20％-23％,the lowest rate was 18.7％in 2012,and the highest rate was 22.9％in 2015.In the past 10 years,the resistance rates of Escherichia spp.to ampicillin,ceftriaxone,cefotaxime and ampicillin/sulbactam were＞80％,＞47％,＞45％,and＞39％,respectively;resistance rates to piperacillin/tazobactam,cefoperazone/sulbactam,and nitrofurantoin were all＜8％,to tigecycline,amikacin,imipenem,and meropenem(except in 2012)were all＜5％.Resistance of Escherichia spp.to 22 commonly clinically used antimicrobial agents fluctuated,but overall trend decreased year by year.The resistance rates of Escherichia spp.from patients in the intensive care unit(ICU),non-ICU patients,outpatients,and emergency patients to 22 clinically commonly used antimicrobial agents were compared among different depart-ments,and the differences were statistically significant(all P＜0.05).The resistance rates of Escherichia spp.iso-lated from ICU and non-ICU patients were compared,and except for tigecycline,the resistance rates to the other 21 antimicrobial agents were statistically different(all P＜0.05).The resistance rates of Escherichia spp.isolated from patients to commonly clinically used antimicrobial agents were statistically different among patients of different age groups(all P＜0.05).Conclusion Escherichia spp.isolated from patients in different years,departments,specimens,and ages have different resistance to commonly used antimicrobial agents.It is necessary to continue to strengthen the surveillance on bacterial resistance,so as to guide the rational choice of antimicrobial agents.

Objective:To analyze the effect of recombinant human thrombopoietin(rhTPO)on platelet(PLT)reconstitution after autologous peripheral blood stem cell transplantation(APBSCT)in patients with multiple myeloma(MM).Methods:The clinical data of 147 MM patients who were diagnosed in the First Affiliated Hospital of Soochow University and received APBSCT as the first-line therapy were retrospectively analyzed.According to whether rhTPO was used during APBSCT,the patients were divided into rhTPO group(80 cases)and control group(67 cases).The time of PLT engraftment,blood product infusion requirements,the proportion of patients with PLT recovery to ≥ 50 × 109/L and ≥ 100 × 109/L at+14 days and+100 days after transplantation,and adverse reactions including the incidence of bleeding were compared between the two groups.Results:There were no significant differences between the two groups in sex,age,M protein type,PLT count at the initial diagnosis,median duration of induction therapy before APBSCT,and number of CD34+cells reinfused(all P＞0.05).The median time of PLT engraftment in the rhTPO group was 10(6-14)days,which was shorter than 11(8-23)days in the control group(P＜0.001).The median PLT transfusion requirement in the rhTPO group during APBSCT was 15(0-50)U,which was less than 20(0-80)U in the control group(P=0.001).At+14 days after transplantation,the proportions of patients with PLT 2 50 × 109/L in the rhTPO group and the control group were 66.3％and 52.2％,while the proportions of patients with PLT ≥ 100 × 109/L were 23.8％and 11.9％,respectively,with no significant differences(all P＞0.05).At+100 days after transplantation,the proportion of patients with PLT ≥ 50 × 109/L in rhTPO group and control group was 96.3％and 89.6％,respectively(P＞0.05),but the proportion of patients with PLT ≥ 100 × 109/L in rhTPO group was higher than that in control group(75.0％vs 55.2％,P=0.012).There was no difference in the overall incidence of bleeding events in different locations during period of low PLT level of patients between the two groups.In rhTPO group,the rhTPO administration was well tolerated,and the incidences of abnormal liver and kidney function and infection were similar to those in the control group.Conclusion:When MM patients undergo first-line APBSCT,subcutaneous injection of rhTPO can shorten the time of platelet engraftment,reduce the transfusion volume of blood products,and be well tolerated,moreover,more patients have achieve a high level of PLT recovery after transplantation,which is very important for ensuring the safety of APBSCT and maintenance therapy.

Objective:To summarize the clinical characteristics of patients with combined pneumocystis jiroveci pneumonia (PJP ) after allogeneic hematopoietic stem cell transplantation (allo-HSCT ). Methods:The clinical manifestations,laboratory tests,imaging findings,and treatment outcomes of 21 allo-HSCT patients with PJP diagnosed at the First Affiliated Hospital of Soochow University and Soochow Hopes Hematology Hospital from July 2018 to July 2023 were retrospective analyzed.Results:Among the 21 patients,the male-to-female ratio was 2.5:1,and the median age was 36 years old with a range of 15-62 years.The median time to diagnosis of PJP after transplantation was 225 days.The clinical manifestations lack specificity,and the main clinical symptoms include respiratory symptoms (dyspnea,cough,sputum,etc.) and fever.Laboratory examination revealed peripheral blood lymphocyte counts decreased in 15 cases,CD4+T lymphocyte absolute values less than 200 cells/μl in 19 patients,C-reactive protein levels significantly increased in 20 patients,lactate dehydrogenase levels increased in 14 patients,and 1,3-β-D-glucan detection levels increased in 14 patients.Chest CT manifestations can be divided into three types:ground glass type,nodular type,and mixed type.Among them,the incidence of ground glass type was the highest (18/21),with 2 cases of nodular type and 1 case of mixed type.The sequence number of Pneumocystis jiroveci was detected through mNGS (15-57570),and 11 patients had mixed infections.In terms of treatment,TMP-SMX,Caspofungin,and methylprednisolone were administered,and 17 patients achieved improvement in their condition.Four patients died,all of whom died from respiratory failure.Conclusion:PJP is a critically ill condition after hematopoietic stem cell transplantation,and diagnosis is difficult.Early diagnosis can achieve better prognosis.The sensitivity of mNGS in diagnosing PJP is high,providing the possibility of early and accurate diagnosis for clinical practice,which is worthy of application and promotion.