Objective: To propose an improved method for constructing the internal quality control (IQC) framework for ELISA assays and validate its efficacy by statistically analyzing IQC data from nine blood center laboratories. Methods: 1) IQC data was collected from nine blood centers and analyzed using a domestic HBsAg ELISA detection kit as an example. 2) Differences between IQC values across batches within Blood Center 1 were assessed. 3) Statistical analyses were performed on batch usage, number of batches used, days of use, number of QC points, batch-specific means, and coefficients of variation (CV) across all nine centers. 4) Using the improved construction method for IQC framework, provisional and permanent frames were established for batches within Blood Center 1 and Blood Center 9, followed by outlier determination. Results: 1) Statistically significant differences were observed in IQC data between batches within Blood Center 1 (P<0.01). It is recommended that both the control material/reagents and the control chart framework be replaced simultaneously. 2) There were substantial differences among 9 blood centers regarding the control material/reagent lot numbers used, the number of QC runs per batch, and the QC values for identical lots. Therefore, individual laboratories should establish their own IQC chart frameworks. 3) The improved IQC framework construction method for ELISA assays is as follows: provisional frames are established via frame-shifting, using the pre-experimental mean and cumulative coefficient of variation (CV) from the preceding batch. For batches used >20 days with >20 QC points, permanent frames are constructed by aggregating in-control data accumulated over ≥20 days with ≥20 points to calculate cumulative mean and standard deviation. The provisional and permanent frames constructed by this method identified all 26 extreme outliers across Blood Centers 1 and 9 as out-of-control. Among the 218 general outliers, 10 were classified as normal by the provisional frames, while the remainder were designated as warnings or out-of-control. This method effectively monitors assay stability. Conclusion: Based on the statistical analysis of IQC practices across blood centers of varying scales, combined with the inherent characteristics of ELISA assays and the batch-to-batch instability of reagents/QC materials, it is recommended to reconstruct QC charts upon lot changes. The proposed method—utilizing frame-shifting for provisional frames and establishing permanent frames based on cumulative data—is applicable to blood center laboratories of differing sizes and effectively monitors the stability of the ELISA assay process.

Objective: To explore the setting of gray zone of Treponema pallidum (TP) testing by retrospective analysis of blood donors with single reagent reactive anti-TP results, so as to improve blood utilization and supply safety. Methods: Blood samples were collected from 112 blood donors previously deferred due to single reagent reactive TP antibody results between January 2020 and December 2023, and subjected to dual ELISA reagents and TPPA test. The gray zone panel analysis was performed on the two ELISA reagents currently used in our department. The detection rate at each concentration of the gray zone panle was counted, and the corresponding concentrations for C , C , and C and gray zone cut-off were calculated. Results: Among the 50 samples deferred by reagent 1, 19 were confirmed reactive and 31 non-reactive in supplementary testing. Among the 62 samples deferred by reagent 2, 12 were confirmed reactive and 50 non-reactive in supplementary testing. For reagent 1, the detection rate of was 56% for S/CO≥1 and 20% for 0.5≤S/CO<1, retrospectively. For reagent 2, the detection rate was 27% for S/CO≥1 and 12.5% for 0.5≤S/CO<1, retrospectively. The detection rate for S/CO≥1 was higher than those for 0.5≤S/CO<1 for both reagents. All the 112 samples were negative in TPPA test. The C concentration of reagent 1 was 1.51 mIU/mL, and the concentration range of C ±20% was 1.21-1.81 mIU/mL. The C concentration of reagent 2 was 1.45 mIU/mL, and the concentration range of C ±20% was 1.16-1.74 mIU/mL. The C and C concentration of both reagents were within the C ±20% range, suggesting that the gray zone cutoff for both Reagent 1 and Reagent 2 should be set at S/CO=0.8 (80% of the CO value). Conclusion: All anti-TP single reagent reactive samples with S/CO value within the gray zone was tested negative by TPPA. It is necessary to consider the rationality and necessity of establishing the gray zone, so as to ensure blood safety and improve the utilization rate of blood resources.

Objective: To investigate the incidence, characteristics, and influencing factors of resolution discrepancies within the minipool (MP) testing model across Chinese blood station laboratories in 2024. Methods: A nationwide, multicenter, cross-sectional study was conducted, including 334 blood station laboratories that reported nucleic acid reactive data among enzyme immunoassay non-reactive samples. Of these, 296 laboratories adopted the pool resolution model, with a total of 12 536 273 samples tested. Systematic analysis was performed on resolution data, focusing on the MP-NAT reactivity rate, the pool resolution concordance rate, and the resolution discrepancy rate. Subgroup analyses were conducted based on reagent types, viral targets, and Ct values. Potential causes were further explored through laboratory surveys and re-examination of raw amplification curves. Results: In 2024, the national average MP-NAT reactivity rate was 0.15%. The overall pool resolution concordance rate was 57.86%, which showed a gradual decline as Ct values increased across all reagents. The national average resolution discrepancy rate was 0.081‱(102/12 536 273), with 17.91%(53/296) of laboratories reporting at least one discrepancy. Nine reagent types were associated with these events, exhibiting reagent-specific patterns. For Reagent A2, the predominant discrepancy was HBV reactive pools resolving as HIV (36.36%); for Reagent D1, HBV pools frequently resolved as HCV (38.89%); and for Reagent E, the most common pattern was HIV pools resolving as HBV (48.00%). These resolution discrepancies were strongly associated with high Ct values: the median pool Ct for HBV exceeded 38, while those for HCV and HIV both exceeded 40. Investigations across 16 laboratories revealed that most discrepant samples exhibited “tailing” amplification curves, with some cases linked to cross-contamination or reagent batch-specific issues. Conclusion: While the incidence of resolution discrepancies in the MP-NAT model remains low in China, variations exist across different reagents and laboratories. These discrepancies are closely associated with low viral load, reagent performance, and laboratory operational practices.

Objective: To analyze the status of Treponema pallidum (TP) infection among blood donors in Hefei area by evaluating anti-TP reactive donors, and to provide data support for blood screening strategies, evaluation of reagent application, and public health prevention and control strategies. Methods: TPPA confirmation test were performed on 338 anti-TP positive samples of voluntary blood donors at Anhui Blood Center from February to April 2022, July to October 2022, February to June 2023. RPR tests were conducted on samples positive for TPPA. The test results, co-reactivity of TP with HBV, HCV, and HIV, and demographic characteristics of the donors were statistically analyzed. Results: The unqualified rate of anti-TP among blood donors in Hefei area was 0.30% (405/133 587), and the positive rate for TPPA was 67.46% (228/338). Among the TPPA-positive donors, 31.67% were RPR-positive. The co-positive rates of HBV, HCV and HIV in anti-TP reactive blood donors were 0.74% (3/405), 0.49% (2/405), and 1.73% (7/405), respectively, with HIV copositivity being the most common. Most co-positive donors were males aged 31-50 years with a high school education or lower, and all were first-time whole blood donors. Conclusion: The anti-TP unqualified rate among blood donors in Hefei area is at a low-to-mederate level. HIV is the most common co-infection with TP among anti-TP positive donors. The majority of co-infected donors are middle-aged men donating whole blood for the first time.

Based on plasma lipidomics combined with machine learning approaches, this study aimed to screen molecular biomarkers for the diagnosis of early-stage lung cancer in elderly patients and to evaluate their diagnostic performance.

Attention refers to the body's capacity to maintain alert awareness of internal and external stimuli.Attention deficit can impair an individual's learning capacity and working proficiency,resulting in a heavy burden to the family and society.Vagus nerve stimulation(VNS)is an emerging neuro regulatory technique that can achieve reciprocal interaction between the central and peripheral nervous systems,which has demonstrated great potential for the treatment of neurological and psychiatric diseases;however,it has not been used clinically to treat attention-deficient developmental disorders in children or neurodegenerative diseases in the aged population.We briefly review the anatomical and physiological bases of VNS,and its application status and potential use in treating attention deficit diseases.A potential mechanism by which VNS participates in attention-related nervous regulation is proposed,to lay a theoretical foundation for the application of VNS in the field of attention nervous regulation.

OBJECTIVE To explore the risk factors for hospital-associated infections(HAI)in dead patients so as to provide bases for development of prevention strategies for the hospital-associated infections.METHODS Totally 560 patients who died due to non-SARS-CoV-2 infections and hospitalized in Gansu Provincial People's Hospital for more than 48 hours in 2019 and 2023 were retrospectively analyzed,70 of whom had HAI and were assigned as the HAI group,and the rest of 490 patients were assigned as the non-HAI group.The incidence of HAI,major causes of death,risk factors and economic burden were observed.RESULTS The incidence of HAI was 12.50％a-mong the dead patients,the lower respiratory tract infection was the predominant type of infection,and the re-spiratory failure was the primary and direct cause of death in the HAI group;the total treatment cost of the HAI group was higher than that of the non-HAI group(P＜0.05).Univariate analysis showed that there were signifi-cant differences in the length of hospital stay,multidrug-resistant organisms infections,combined use of antibiot-ics,surgery,hemodialysis/peritoneal dialysis,invasive procedures(drainage,puncture,intubation,tracheoto-my),use of equipment like ventilator or urinary catheter,central venous catheter indwelling,blood transfusion,and use of immunosuppressors/glucocorticoids between the HAI group and the non-HAI group(P＜0.05),while there were no significant differences in the sex,age,underlying diseases,modified early warning score(MEWS)and major diagnosis and chemoradiotherapy between the two groups.Multivariate analysis indicated that the length of hospital stay more than 14 days,history of surgery and combined use of antibiotics were the risk factors for HAI in the dead patients(P＜0.05).CONCLUSION It is necessary for the hospital to identify the high-risk pa-tients as early as possible,pay close attention to the lower respiratory tract infection,reduce the risk of HAI by shortening the length of hospital stay,standardizing the invasive procedures and reasonably using antibiotics so as to improve the prognosis of the patients.

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.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.