OBJECTIVE:To establish a method for the content determination of sinomenine in Qihuang capsule. METHODS:HPLC was performed on the column of welch C18-AQ with mobile phase of methanol-phosphate buffer(gradient elution) at flow rate of 1.0 ml/min,detection wavelength was 264 nm,column temperature was 30 ℃ and volume injection was 10 μl. RESULTS:The linear range of sinomenine was 0.200 3-10.016 0 μg(r=0.999 8),RSDs of precision,stability and reproducibility tests were lower than 1.0%,recovery was 98.80%-100.94%(RSD=0.79%,n=6). CONCLUSIONS:The method is simple,accurate and re-producible,and can be used for the content determination of sinomenine in Qihuang capsule.

OBJECTIVE:To establish a method for the content determination of hordenine in Zang medicine Herba Aconiti. METHODS:HPLC was performed on the column of Gemini-NX C18 with mobile phase of acetonitrile-0.25 mol/l Ammonium ace-tate solution(ammonia water to adjust the pH to 9.5,gradient elution,at flow rate of 1 ml/min,the detection wavelength was 230 nm,the column temperature was 30 ℃,and the injection volume was 20 μl.RESULTS:The linear range of hordenine was 3.276-819μg/ml(r=0.999 5);RSDs of precision,stability and reproducibility tests were lower than 2.0%;recovery was 96.21%-104.04%(RSD=1.23%,n=9). CONCLUSIONS:The method is simple,stable and reproducible,and can be used for the content determi-nation of hordenine in Zang medicine Herba Aconiti.

Objective:To analyze human factors in radiotherapy safety incidents and identify their correction for the purpose of mining the latent incident chains.Methods:A total of 60 radiotherapy safety incidents were included in the Radiation Oncology Incident Learning System (ROILS) for cause identification and frequency statistics using the Human Factors Analysis and Classification System (HFACS). Latent class analysis (LCA) was performed for the result to correlate the incident causes.Results:Incidents in the protocol design stage were the most common, accounting for 35%. Adverse organizational climate, inadequate supervision, and personnel factors were the primary causes of incidents at each level of the HFACS, accounting for 4.66%, 15.68%, and 16.20%, respectively. Three latent incident chains were identified through LCA, comprising two originating from organizational climate issues and one from organizational process issues, which were passed down via various human factors or " loopholes"Conclusions:HFACS assists in tracing the human factors at all levels that lead to radiotherapy safety incidents. The high-frequency causes and three latent chains of radiotherapy incidents found in this study can provide a guide for the development of targeted safety and defense measures.

Objective:To investigate the dosimetric effects of complex cardiac-respiratory motion in cardiac stereotactic body radiotherapy (CSBRT).Methods:A cardiac motion phantom was employed to simulate patient-specific cardiac-respiratory motion in 10 cases. The measured doses obtained under the phantom motion state were compared with the calculated doses in radiotherapy treatment planning for clinical patients. Moreover, 18 groups of design-based cardiac-respiratory motion were simulated. The radiation doses under the phantom motion state were measured using radiochromic films and compared with those under the resting state.Results:In the patient-specific cardiac-respiratory motion group, the gamma passing rate (GPR) under the 3%/2 mm standard between the measured and the calculated doses was 90.0% ± 7.0%. The correlation coefficient of the respiratory motion amplitude in the superior-inferior (SI) dimension with the GPR was -0.86 ( P=0.01). In the design-based cardiac-respiratory motion groups, the increase in the amplitude of cardiac-respiratory motion reduced the consistency between the dynamic dose and the static reference dose. Especially, the increase in the respiratory motion amplitude produced the most pronounced effect, reducing the width of the 90% isodose line in the respiratory motion direction, with a mean slope of -1.6. Additionally, the increase in the penumbra corresponds to a mean slope of 1.4. Conclusions:The respiratory motion amplitude serves as a primary factor influencing the dose accuracy of CBSRT. The characteristics and dosimetric effects of cardiac-respiratory motion are patient-specific, thus necessitating the assessment of cardiac-respiratory motion characteristics before CBSRT to individualize the application of motion management techniques for enhanced treatment accuracy.