OBJECTIVE To evaluate the anticoagulant efficacy and safety of nafamostat mesylate （NM） in the treatment of uremic patients at high risk of bleeding undergoing continuous veno-venous hemofiltration （CVVH） with different methods （pre- dilution and post-dilution）. METHODS A total of 130 uremic patients at high risk of bleeding who underwent CVVH treatment in the nephrology department of Chongqing University Three Gorges Hospital from July 2023 to September 2024 were selected. They were divided into pre-dilution group and post-dilution group according to the random number table method， with 65 cases in each group. Both groups of patients received CVVH treatment under NM anticoagulation. The pre-dilution group adopted the pre-dilution replacement method， while the post-dilution group adopted the post-dilution replacement method. The coagulation， pressure， and usage duration of the filter and dialysis circuit venous reservoirs were compared between the two groups. The changes in prothrombin time （PT）， prothrombin time-international normalized ratio （PT-INR）， activated partial thromboplastin time （APTT）， and fibrinogen （FIB） in the peripheral venous blood before the heparin pump and after the filter at 1， 4 and 7 h of CVVH treatment， as well as 20 min after the end of treatment， were compared between the two groups. The single-compartment urea clearance rate （spKt/V）， β2-microglobulin （β2-MG） clearance rate and the incidence of adverse reactions were duni2007@foxmail.com compared between the two groups. RESULTS Both the pre-dilution and post-dilution groups had 60 patients who completed the study. The incidence of grade Ⅱ-Ⅲ coagulation of the filter and venous reservoirs， as well as the number of patients with transmembrane and venous pressure alarm intervention in the post- dilution group were significantly higher or more than those in the pre-dilution group （P＜0.05）， while usage time of the filter and the pipeline in the post-dilution group was significantly shorter than that in the pre-dilution group （P＜0.05）. The APTT values before the heparin pump as well as PT and APTT values after the filter at 1 h， 4 h， and 7 h of CVVH treatment in the post-dilution group were significantly higher than those in the pre-dilution group （P＜0.001）. There were no significant differences in PT， PT- INR， APTT and FIB between the two groups of patients 20 min after the end of treatment （P＞0.05）. The spKt/v and β2-MG clearance rates in the post-dilution group were significantly higher than those in the pre-dilution group （P＜0.001）. There was no significant difference in the incidence of adverse reactions between the two groups （P＞0.05）. CONCLUSIONS When NM is used as an anticoagulant in the CVVH treatment of uremic patients at high risk of bleeding， compared with the pre-dilution treatment method， the post-dilution treatment method has a higher incidence of filter and dialysis tubing venous reservoir， a shorter usage time of the filter and pipeline， and a greater impact on extracorporeal coagulation， but has a higher solute clearance rate. Clinically， different dilution methods can be selected according to the different treatment needs of patients.

Aim To establish and evaluate an alternative meth-od for detecting skin sensitization of cosmetics based on local lymph node assay using bromodeoxyuridine(BrdU)with flow cytometry(FCM).Methods(1)25％hexyl cinnamic alde-hyde(HCA)was chosen as a positive control with an acetone:olive oil(4∶1,V/V,AOO)mixture as a vehicle control for the experiment.The dorsal sides of both ears of mice were treated with test solutions on day 1,day 2,and day 3.Brdu solution was injected inter-peritoneally on day 5.On day 6,the bilateral ears and mandibular lymph nodes were excised,and the number of Brdu positive cells was measured by flow cytometry.The stim-ulation index(SI)was calculated to identify whether it was ≥3,in order to establish the method of LLNA:Brdu-FCM.(2)BrdU-FCM test was conducted using a blind method with the fif-teen reference substances listed in OECD TG429 whose skin sensitization potentials were known.The test substances were dissolved in AOO,N,N-dimethylformamide(DMF)or dimeth-yl sulfoxide(DMSO)at three different concentrations.Tests were performed the same as above.SI and EC2.7 were calculat-ed to evaluate whether the test substance was categorized as a skin sensitizer.The reliability and accuracy of the method were validated by comparing the classification of test substances with that in OECD TG429.Results The SI for 25％HCA was 3.9,showing positive in the skin sensitization test.It demonstrated that the LLNA:Brdu-FCM test method was properly implemen-ted.Nine test substances(2,4-dinitrochlorobenzene,4-pheny-lenediamine,cobalt chloride,2-mercaptobenzothiazole,hexyl-cinnamaldehyde,eugenol,phenyl benzoate,cinnamic alcohol,imidazolidinyl urea)were positive,and six test substances(methyl methacrylate,chlorobenzene,isopropanol,lactic acid,methyl salicylate,salicylic acid)were negative.The method was evaluated with sensitivity of 90％,specificity of 100％,positive prediction rate of 100％,negative prediction rate of 83％,false positive rate of 0％,false negative rate of 17％and accuracy of 93％.The LLNA:BrdU-FCM assay could correctly categorize the test substances that were skin sensitizers or non-sensitizers.Conclusion The LLNA:BrdU-FCM assay appears to be a relia-ble predictor of skin sensitization protential of chemicals,and it is expected to an alternative method for identifying skin sensitization as a supplementary in safety evaluation of cosmetic ingredient.

Objective To identify and cluster non-O1/O139 Vibrio cholerae(NOVC)using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS),and evaluate the feasibility of MALDI-TOF MS as a method for the identification and clustering of NOVC.Methods The NOVC was identified by the MALDI-TOF MS equipped with V5 database,V12 database,highly pathogenic bacteria database,and V5 database combined with self-built spectrum projection and analyzed by the principal com-ponent analysis(PCA)and main spectrum projection(MSP)clustering.Results The NOVC was incorrectly identified as Vibrio al-bensis by the MALDI-TOF MS equipped with V5 database or V12 database,while the MALDI-TOF MS equipped with highly pathogenic bacteria database or V5 database combined with self-built spectrum projection could correctly identify NOVC.The PCA clustering of MALDI-TOF MS could distinguish NOVC from other bacterial strains and refine the differentiation of NOVC species to show the dis-tance relationship between NOVC species.Some spectrum projections of NOVC were extremely similar to the reference strains used to establish the database,and MSP clustering could not distinguish the differences between NOVC species.Conclusion The identifica-tion ability of MALDI-TOF MS for NOVC is limited by its database.The MALDI-TOF MS equipped with highly pathogenic bacteria da-tabase or V5 database combined with the self-built spectrum projection can accurately identify NOVC.The PCA clustering of MALDI-TOF MS has certain reference significance for the intra-and inter-species identification and homology analysis of NOVC.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

The purpose of this study is to develop a shark single domain antibody(SdAb)targeting a unique B cell epitope in the SARS-CoV-2 spike protein,and explore its role in the immunological detection targeting SARS-CoV-2 spike protein S.A u-nique peptide S9 was artificially synthesized based on the sequence of a unique B cell epitope of SARS-CoV-2 spike protein,then it was conjugated to the carrier protein KLH.It was used as an immunogen for subcutaneous injection into shark back and boosted according to the standard immunization protocol.Blood collected from shark tail vein and peripheral blood lymphocytes(PBL)were isolated.Total RNA was purified from PBL and transcribed to cDNA by reverse transcription.Shark vNAR frag-ments were amplified from cDNA templates and cloned into pComb3XSS vector to obtain phage library.A positive clone named T01 was obtained through screening the phage library by indirect ELISA.Then its gene was cloned into the expression vector pET-28a.The SdAb T01 was then prokaryotically expressed and purified,and its specific recognition of the SARS-CoV-2 spike protein S was indentified by Western-blot(WB),indirect ELISA and IF A.T01 binds well with peptide S9 at EC50 value of 2.050±0.064 nmol/L.The purified SdAb T01 was proven by WB to be able to selectively detect recombinant spike protein sub-unit 1(S1)of SARS-CoV-2,with no cross-reactive to recombinant spike protein subunit 1 of other six human coronavirus.It was showed by ELISA that SdAb T01 can sensitively detect the recombinant N terminal domain(NTD)of SARS-CoV-2 pro-tein.Moreover,it also specifically recognizes the spike protein of SARS-CoV-2 that was transiently expressed in transfected HEK293 cells by IFA.Therefore,a shark single domain antibody targeting a unique B cell epitope in the spike protein of SARS-CoV-2 was successfully developed,and has shown potential immunodiagnostic value by WB,ELISA and IFA.Thus,it provides an effective tool for unique antigen detection of SARS-CoV-2.

Objective To formulate the drug packaging material method standards in the 2025 edition of the Pharmacopoeia of the People's Republic of China(referred to as the"Chinese Pharmacopoeia"),to develop the method for the determination of extractable tungsten for prefilled syringes,and to interpret the content of the method to provide guidance and help for its subsequent implementation.Methods The formulation process of"Determination of Extractable Tungsten for Prefilled Syringes"was described.Combining the current domestic and foreign relevant standards,the extraction conditions of samples were explored and verified,and the determination methods of inductively coupled plasma optical emission spectrometer(ICP-OES)and inductively coupled plasma mass spectrometer(ICP-MS)were verified.Results A method was established for extracting tungsten from glass prefilled syringes utilizing water and 0.01 mol·L-1 sodium hydroxide solution as extraction media,respectively,at 75 ℃ through ultrasound.The dissolution amount of tungsten was determined by inductively coupled plasma opticalemission spectrometry(ICP-OES)and inductively coupled plasma mass spectrometry(ICP-MS).Among them,the extraction using 0.01 mol·L-1 sodium hydroxide solution as the extraction medium is a stricter and acceptable alternative approach.Conclusion According to the quality control requirements of products,corporations can choose the appropriate extraction medium according to the method in this standard for the determination of tungsten dissolution in the prefilled syringes.

To analyze the standard establishment approach and compilation rationale for metallic pharmaceutical packaging standard development in the 2025 edition of the Pharmacopeia of the People's Republic of China.This article systematically explained the background and process of establishing the guiding principles for metallic materials and containers used in pharmaceutical packaging in the Chinese Pharmacopoeia through basic information,relevant domestic and international standards,the establishment of key quality attributes of metallic pharmaceutical packaging materials,and the construction of metallic pharmaceutical packaging material standards.The newly established guidelines,the Pharmacopeia of the People's Republic of China 9625,prioritized product critical quality attributes(CQAs)and real-world applicability.This dual emphasis on rigidity and adaptability enhances drug safety,meets the regulatory requirements,and promotes the globalization and scientific advancement of China's pharmaceutical packaging industry.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To explore the value of deep learning image reconstruction(DLIR)combined with"three low(low radiation dose,low contrast dose,and low contrast injection rate)techniques"of spectrum CT with low keV in optimizing the image quality of portal vein for liver cirrhosis.Methods Sixty patients with liver cirrhosis who underwent computed tomography portal venography(CTPV)were selected and randomly divided into standard protocol group(group A,n=30)and"three-low"protocol group(group B,n=30).The group A with 120 kVp,contrast dose of 1.4 mL/kg,injection rate of 4.0-5.0 mL/s,and reconstructed 50%adaptive statistical iterative reconstruction-Veo(ASIR-V)image.The group B with 80 kVp/140 kVp double instantaneous switching gemstone spectral imaging(GSI)scan,contrast dose of 1.0 mL/kg,injection rate of 3.0-3.5 mL/s,and reconstructed 40 keV DLIR-M and DLIR-H images.The quality of portal vein images,effective dose(ED),contrast dose and injection rate were compared between the two groups.Results The ED of(4.10±1.56)mSv in group B was lower than that of(7.88±1.08)mSv in group A(P<0.001),and the contrast dose of(67.26±8.74)mL in group B was lower than that of(99.12±8.84)mL in group A(P<0.001).The injection rate of 3.0-3.5 mL/s in group B was reduced by 25%-30%compared with group A.Group B had the greatest contrast-to-noise ratio(CNR)and signal-to-noise ratio(SNR)of portal vein in the 40 keV DLIR-H.The subjective image quality scores were in good agreement between the two physicians(Kappa value>0.75).The subjective DLIR score in group B was higher than that in group A.Conclusion DLIR combined with"three low techniques"spectrum CT with low keV can improve the image quality of portal vein in liver cirrhosis patients.