BACKGROUND:Research on ethyl pyruvate detection methods is reported rarely, and moreover, literature about reversed-phase high-performance liquid chromatography (RP-HPLC) for detection of ethyl pyruvate is less.
OBJECTIVE:To establish an RP-HPLC method for determination of ethyl pyruvate in ethyl pyruvate-chitosan nanoparticles.
METHODS: The chromatographic analysis was performed on a ZORBAX Eclipse XDB-C18 column (4.6 mm× 150 mm, 5μm) at 25℃, with the mixture of acetonitrile and water (40:60, V/V) as the mobile phase at the flow rate of 1 mL/min. The determination wavelength wasset at 210 nm and the injection volume was 20 μL.
RESULTS AND CONCLUSION: The peak of ethyl pyruvate and the peaks of auxiliary materials and solvent were separated wel. The linear rang of ethyl pyruvate was 1-100 mg/L (r=0.999 6). The relative standard deviation of both the intra-and inter-day precision was less than 3% for low-, moderate-, and high-concentration ethyl pyruvate. The relative standard deviation of reproducibility test and stability test was 1.25% and 1.3%, respectively. Sample average recovery rates were (91.5±1.0)%, (3.5±0.2)%, (94.4±0.4)%, respectively. Encapsulation efficiency of samples were (87.2±0.22)%, (90.5±0.15)%, (91.1±0.17)%, respectively. The relative standard deviation of different sample content were 0.9%, 0.5%, 0.3%, respectively. The RP-HPLC method for determination of ethyl pyruvate is sensitive, accurate and highly specific with wide linear range and high sample average recovery.

The initiative and enthusiasm of medical staff in teaching work are the sources of improving the quality of clin-ical teaching.Stimulating the teaching enthusiasm of clinical teachers is an important connotation of the sustainable and high-quality development of teaching hospital.This article aims to establish a point-based teaching performance evaluation system to evaluate clinical teachers,stimulate the enthusiasm of medical staff to participate in clinical teaching activities,and promote clin-ical standardization through teaching.

Objective:To retrospectively compare the clinical efficacy of percutaneous vertebroplasty and biopsy by unilateral and bilateral pedicle approaches for the treatment of vertebral metastasis.Methods:From June 2020 to July 2022, a total of 82 patients with vertebral metastasis underwent percutaneous vertebroplasty and biopsy treated in Linyi Cancer Hospital were enrolled, 39 patients with 57 vertebral bodies were performed by unilateral pedicle approach (unilateral group) and 43 patients with 52 vertebral bodies were performed by bilateral pedicle approaches (bilateral group), used bone cement filling vertebral bodies after biopsy. The clinical efficacy and the positive rate of biopsy were compared between the two groups.Results:Both groups experienced significant pain relief in the Visual Analog Scale (VAS) score and improvement in the Oswestry Disability Index (ODI) score after operation ( P<0.05), but there were no significant differences between the two groups ( P>0.05). The operative time for a single vertebra, volume of bone cement in unilateral group were less than those in the bilateral group:(44.81 ± 13.01) min vs. (31.84 ± 11.87) min, (4.87 ± 0.92) ml vs. (4.18 ± 0.90) ml, there were significant differences ( P<0.05). There were no significant differences in the incidence of bone cement leakage and the positive rate of biopsy between both groups ( P>0.05). Conclusions:Percutaneous vertebroplasty and biopsy by unilateral and bilateral pedicle approaches are significant improvement for symptoms and functions of patients with vertebral metastasis. The clinical efficacy and the positive rate of biopsy are similar. But the former has easier operation procedure, shorter operative time and less volume of bone cement.