Objective To improve and establish an RP-HPLC method for the determination of related substances of piracetam and its injection. Methods Using thermo syncronis C18(4.6 mm ×250 mm,5μm)chromatographic column, mobile phase was acetonitrile-phosphate buffer (adjust pH of 1.0 g/L potassium hydrogen phosphate solution to 6.0 with phosphoric acid), gradient elution with initial mobile phase 5% acetonitrile.The flow rate was 1 mL/min, detected at 205 nm.Five calibration factors of the known impurities were separately measured.the related substances were determined using main component self-compare with calibration factor.Results Piracetam and their related substances were well separated.The calibration curves of five known impurity A~E were linear within the concentration range measured.The average recoveries were 99.46%,98.21%,97.22%,100.23% and 97.58%, respectively(n=9), RSDs of the average recoveries were lower than 2.0%.The calibration factors of five known impurity A ~E were 1.1, 1.4,1.5,0.8, 1.4, respectively.Conclusion The method can be used to determine the related substances in piracetam and its injection.The related substances can be determined accurately using main component self-compare with calibration factor.

Objective:To investigate the diagnostic value of thyroid imaging report and data system (TIRADS) combined with BRAF V600E mutation detection in differentiating uncertain thyroid nodules by using fine needle aspiration cytology (FNAC), and to analyze the role of TIRADS classification in screening the nodules needed to be routinely detected for BRAF V600E mutation.Methods:The clinicopathological data of 337 thyroid nodules patients diagnosed with TIRADS classification, FNAC Bethesda classification, BRAF V600E mutation detection and postoperative histopathology from the Second Hospital of Hebei Medical University between January 2018 and August 2021 were retrospectively analyzed. The role of TIRADS classification, FNAC Bethesda classification and BRAF V600E mutation detection alone and the combined detection in the differentiation of benign and malignant thyroid nodules was also analyzed.Results:The postoperative histopathological result was regarded as the gold standard. The sensitivity of TIRADS classification, FNAC Bethesda classification and BRAF V600E mutation for thyroid cancer diagnosis was 76.0%, 88.1% and 80.4% respectively, and the corresponding specificity was 84.0%, 96.0% and 100.0%, respectively. Histologically, 37 (62.7%) of 59 nodules with FNAC uncertainty were malignant nodules after the surgery. The sensitivity and accuracy of BRAF V600E mutation detection in the diagnosis of FNAC uncertain nodules were 51.4% and 69.5%, respectively, while the sensitivity and accuracy of BRAF V600E mutation detection combined with TIRADS classification were 86.5% and 84.7%, respectively. The sensitivity and accuracy of BRAF V600E mutation detection combined with TIRADS classification were both improved ( P values were 0.002 and 0.049, respectively). The positive rate of BRAF V600E mutation in thyroid nodules increased step by step with the rise of risk degree in TIRADS classification, and the type 3 cases were lower than those in type 4a cases [14.3% (1/7) vs. 68.6% (24/35), P = 0.012], and there were no statistically significant differences among the adjacent groups above 4a (all P > 0.05). Conclusions:TIRADS combined with BRAF V600E mutation detection can improve the sensitivity and accuracy in the diagnosis of FNAC uncertain thyroid nodules. The BRAF V600E mutation rate of TIRADS 4a and above nodules is high, so routine detection is recommended.