External quality assessment for molecular detection of Ureaplasma urealyticum in China.

BACKGROUND AND AIMS: A pilot external quality assessment (EQA) scheme for molecular detection of Ureaplasma urealyticum (UU) was conducted by the National Center for Clinical Laboratories (NCCL) to evaluate the testing capabilities of clinical laboratories and the actual performance of DNA-based nucleic acid amplification tests (NAAT) and RNA-based NAATs when applied in clinical settings. MATERIALS AND METHODS: The EQA panel contained twelve lyophilized samples, including positive samples containing inactivated cell culture supernatants of UU at different concentrations and sterile saline for negative samples. The positive samples were further divided into three groups of high, moderate and low concentrations. The panels were distributed to the participants and the datasets were analyzed according to the qualitative results. RESULTS: A total of 365 laboratories participated in the EQA scheme, and 360 results submitted by 338 laboratories were collected, of which 96.11 % (346/360) of the returned results and 95.86 % (324/338) of the laboratories were deemed competent. The positive percentage agreement (PPA) was ≥ 97.5 % for high and moderate concentration samples, but varied significantly for low concentration samples, decreasing from 86.94 % to 51.94 % as the sample concentration decreased. Additionally, for low concentration samples, RNA-based NAAT showed higher PPAs than DNA-based NAATs, but these results were specific to UU supernatants used in this study. CONCLUSION: Most of UU detection assays employed by the participants were generally consistent with their estimated limit of detection (LOD), and the majority of participants can reliably detect UU samples with high and moderate concentrations, while the poor analytical performance for low concentration samples requires further improvement and optimization.

Performance evaluation of SARS-CoV-2 antigen detection in the post-pandemic era: multi-laboratory assessment.

OBJECTIVES: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen detection is an indispensable tool for epidemic surveillance in the post-pandemic era. Faced with irregular performance, a comprehensive external quality assessment (EQA) scheme was conducted by the National Center for Clinical Laboratories (NCCL) to evaluate the analytical performance and status of SARS-CoV-2 antigen tests. METHODS: The EQA panel included ten lyophilized samples containing serial 5-fold dilutions of inactivated SARS-CoV-2-positive supernatants of the Omicron BA.1 and BA.5 strains and negative samples, which were classified into "validating" samples and "educational" samples. Data were analyzed according to qualitative results for each sample. RESULTS: A total of 339 laboratories in China participated in this EQA scheme, and 378 effective results were collected. All validating samples were correctly reported by 90.56 % (307/339) of the participants and 90.21 % (341/378) of the datasets. The positive percent agreement (PPA) was >99 % for samples with concentrations of 2 × 107 copies/mL but was 92.20 % (697/756) for 4 × 106 copies/mL and 25.26 % (382/1,512) for 8 × 105 copies/mL samples. Colloidal gold was the most frequently used (84.66 %, 320/378) but showed the lowest PPAs (57.11 %, 1,462/2,560) for positive samples compared with fluorescence immunochromatography (90 %, 36/40) and latex chromatography (79.01 %, 335/424). Among 11 assays used in more than 10 clinical laboratories, ACON showed a higher sensitivity than other assays. CONCLUSIONS: The EQA study can help to validate whether it's necessary to update antigen detection assays for manufacturers and provide participants with information about the performance of assays to take the first step toward routine post-market surveillance.

Effectiveness and Economic Evaluation of Polyene Phosphatidyl Choline in Patients With Liver Diseases Based on Real-World Research.

Aims: Liver disease has high prevalence, number, and disease burden in China, and polyene phosphatidyl choline (PPC) is a widely used liver protective drug. We aim to explore the effectiveness and economy of PPC in patients with liver diseases based on real-world research and compare with other hepatoprotective drugs. Methods: This is a "three-phase" study from three medical centers, including descriptive study of patients using PPC injection, self-control case study of patients using PPC injection, and specific-disease cohort study of patients using PPC injection or control drugs. The major measurements of liver function for effectiveness analysis were the alanine transaminase (ALT) level changes and recovery rate. The main statistical methods were Wilcoxon signed rank test, χ 2 test, and Mann-Whitney U test. Propensity score matching was applied to reduce bias. Cost-effectiveness analysis, cost minimization analysis, and sensitivity analysis were used for economic evaluation. Results: PPC alone or in combination with glutathione and magnesium isoglycyrrhizinate shows less total hospitalization cost (p < 0.05) and smaller cost-effectiveness ratio and was effective in protecting liver function, especially in patients with liver transplantation or postoperation of nontumor liver disease (ALT decreased significantly after PPC treatment; p < 0.05). Glutathione and magnesium isoglycyrrhizinate combined with PPC could enhance the protective function of liver. Conclusion: PPC was an effective and economic liver protective drug in patients with specific liver diseases, and PPC could enhance the liver protective function of glutathione and magnesium isoglycyrrhizinate.

Development and validation of an improved HPLC-MS/MS method for comparative pharmacokinetics of penehyclidine hydrochloride following a single intravenous or intramuscular injection.

Penehyclidine hydrochloride (PHC) is an anticholinergic drug with both antimuscarinic and antinicotinic activity. In order to compare the pharmacokinetics of two administration routes (intravenous injection (i.v.) and intramuscular injection (i.m.)) of PHC, an improved High Performance Liquid Chromatography Tandem Mass Spectrometry (HPLC-MS/MS) bioanalytical method was developed for the quantification of PHC in plasma and urine using verapamil as the internal standard (I.S.). Chromatography was performed using a Thermo Hypersil GOLD column (30mm×2.1mm, 3µm), with a gradient elution of 1‰ formic acid-10mmol/L ammonium acetate and acetonitrile at 0.3mL/min. Detection and quantitation were performed by electrospray ionization (ESI) and multiple reaction monitoring (MRM) in the positive ion mode. The most intense [M+H](+) MRM transition of PHC at m/z 316.2→128.3 was used for PHC quantitation, and the transition at m/z 454.6→303.2 was used to monitor I.S. The lower limit of quantification (LLOQ) was 0.05 ng/mL. The intraday precision was <6.71% and the interday precision was <11.69%. The pharmacokinetic parameters of i.v. and i.m. administration routes were as follows (i.v. vs i.m.): t1/2 15.73 vs 17.24h, Tmax 0.06 vs 0.26h, AUC0-t 69.35 vs 67.90hng/mL, AUC0-inf 78.24 vs 79.67hng/mL, Cmax 37.5 vs 9.1ng/mL, Ae0-24h 22.7 vs 25.21µg. There were no significant differences between parameters t1/2 and AUC (P>0.05), but significant differences were observed in Cmax, Tmax and Ae0-24h between the two administration routes (P<0.05). The mean absolute bioavailability of the i.m. administration route was 98.4% (95% confidence interval, 93.4-103.6%). Safety results showed that PHC appeared to be well tolerated in both i.v. and i.m. administration routes and pharmacokinetic results showed that PHC was nearly completely absorbed via i.m. administration route.