OBJECTIVE:To determine the contents of secnidazole in secnidazol e tablets by RP-HPLC.METHODS:The chromatographic column was VP-ODS C 18 with acetonirile-0.05mol/L potassium dihydrogen phosphate-triethylamine(15∶85∶0.4)as the mobile phase,the detection wavelength was311nm and the flow rate was0.8ml/min.RESULTS:There was a good linear relationship when the sample size was within the range of0.166?g～0.832?g(r=0.9999),the average re?covery was99.84%(RSD=1.05%,n=15).CONCLUSION:The method is simple and accurate,sensible and reproducible,which can be used for the assaying of both the raw materials and preparations and the quality control of secnidazole tablets.

AIM: To determine the content of terpenelactones in Yinxingye Soft Capsule(Folium Ginkgo). METHODS: HPLC with Evaporative Light Scattering Detector (ELSD) was established to determine the content of terpenelactones in Yinxingye Soft Capsule. The analysis was carried out on C 18 column. The mobile phase was 1-propanol-THF-water(1∶15∶84). The operating conditions of the ELSD were a nebulizer nitrogen flow-rate of 3.5L?min -1 and an evaporator tube temperature of 115℃. RESULTS: No interference was found in the terpenelactones peak position. The method was simple, with a good linear relationship. The relative standard deviation of reproducibility was 1.04% and the average recovery was 97.1%. CONCLUSION: The method can be used for quality control.

Background/Aims: The occurrence and development of hepatitis B virus-associated acute-onchronic liver failure (HBV-ACLF) is closely related to the immune pathway. We explored the heterogeneity of peripheral blood T cell subsets and the characteristics of exhausted T lymphocytes, in an attempt to identify potential therapeutic target molecules for immune dysfunction in ACLF patients. Methods: A total of 83,577 T cells from HBV-ACLF patients and healthy controls were screened for heterogeneity by single-cell RNA sequencing. In addition, exhausted T-lymphocyte subsets were screened to analyze their gene expression profiles, and their developmental trajectories were investigated. Subsequently, the expression of exhausted T cells and their capacity in secreting cytokines (interleukin 2, interferon γ, and tumor necrosis factor α) were validated by flow cytometry. Results: A total of eight stable clusters were identified, among which CD4 + TIGIT + subset and CD8 + LAG-3 + subset, with high expression of exhaust genes, were significantly higher in the HBV-ACLF patients than in normal controls. As shown by pseudotime analysis, T cells experienced a transition from naïve T cells to effector T cells and then exhausted T cells. Flow cytometry confirmed that the CD4 + TIGIT + subset and CD8 + LAG-3 + subset in the peripheral blood of the ACLF patients were significantly higher than those in the healthy controls. Moreover, in vitro cultured CD8 + LAG-3 + T cells were significantly fewer capable of secreting cytokines than CD8 + LAG-3- subset. Conclusions Peripheral blood T cells are heterogeneous in HBV-ACLF. The exhausted T cells markedly increase during the pathogenesis of ACLF, suggesting that T-cell exhaustion is involved in the immune dysfunction of HBV-ACLF patients.