OBJECTIVE: To establish a HPLC method for the determination of content of entecavir and its related substances. METHODS: The HPLC condition was consisted of a Luna C18 column with a column temperature at 25 ℃, using gradient eluate method, the mobile phase was acetonitrile,with a flow rate of 1.0 mL?min-1 and detection at 254 nm. RESULTS: The calibrated linear curve of entecavir was within 0.033 45～0.167 2 mg?mL-1(r=0.999 98). The average recovery was 100.09%,RSD=0.20%, The content of related substance was 0.54%～1.48%. CONCLUSION: This accurate and reliable HPLC method is applicable for the quality control of entecavir and its related substances.

The technology of Magnetic Resonance Spectroscopy(MRS) is a newly-developed mean for analyzing some specific nucleus and their compounds making use of the principles of magnetic resonance and the effects of chemical shift. Currently, among MRS applications, proton magnetic resonance spectroscopy (1HMRS) is the most widely applied one developed from single voxel to three-dimensional multi-voxel scanning technique. It provides a lot of important information for clinical studies. This article mainly reviews the methods for absolute quantification measurement of brain metabolites using multi-voxel MRS.

OBJECTIVE:To establish an RP-HPLC method for content determination of s-omeprazole sodium and its related substances.METHODS:The separation of s-omeprazole sodium and the related substances was carried out on a Phenomenex Luna C18 column,the mobile phase consisted of methanol-0.033 mol?L-1 ammonium dihydrogen phosphate-triethylamine (58∶41.8∶0.2,adjusted to pH 7.0 by phosphate acid).The detection wavelength was 302 nm,the flow rate was 1.0 mL?min-1,the column temperature was 25 ℃,and the sample size was 20 ?L.RESULTS:The linear range of omeprazole sodium was 10～500 mg?L-1 (r=0.999 7).The average recovery rate was 100.27% (RSD=0.74%).The average content of the related substances in samples was 0.42%.CONCLUSION:This method is simple,accurate,specific and applicable for content determination of s-omeprazole sodium and its related substances.

OBJECTIVE:To establishment the method for the determination of content of vitamin A palmitate(VAP) and its related substances by HPLC. METHODS:The HPLC conditions were consisted of Phenomenex Luna C18 column with a mobile phase of a mixture of acetonitrile-isopropanol (90∶10) ,the detection wavelength of 328 nm,the column temperature of 30 ℃ and the flow rate of 1.0 mL?min-1. RESULTS:VAP was completely separated from impurities,the linearity range was 90～400 mg?L-1(r=0.999 2). The average recovery rate was 99.60% (RSD=1.32%). The average content of the related substances were lower than 2.53% . CONCLUSION: This accurate and reliable HPLC method is applicable for the quality control of VAP.

Objective: To analyze the epidemiological characteristics of mumps in Shanxi Province from 2014 to 2023, so as to provide scientific evidence for targeted prevention strategies. Methods: Mumps case data in Shanxi Province were obtained from the China Information System for Disease Prevention and Control. Descriptive epidemiological analysis and age-period-cohort (APC) analysis were carried out on the reported incidence of mumps from 2014 to 2023. Results: A total of 44 360 mumps cases were reported in Shanxi Province from 2014 to 2023, with an average annual incidence rate of 11.78/100 000. The incidence rates were high during 2017-2019, which were 21.00/100 000, 16.76/100 000, and 19.51/100 000, respectively. Males had a higher incidence rate (13.50/100 000) than females (9.98/100 000). Children aged 5-9 years were the most affected group, accounting for 47.29% of total cases. In 2017 and 2019, incidence rates among the 5-15-year-old group were particularly high, reaching 155.08/100 000 and 131.78/100 000, respectively. The APC model age effect, period effect and cohort effect of the reported incidence rate in the high-incidence population aged 0-20 years all had statistical significance ( P <0.05). The age-relative risk ( RR ) decreased from 1.75 in the 0-year-old group to 0.33 in the 20-year-old group, and the birth cohort RR decreased from 2.58 in 1994 to 0.26 in 2023. The morbidity risk of the population aged 0-20 years showed a trend of first increasing and then decreasing over time, among which it was the highest in 2017 ( RR =1.23) and the lowest in 2023 ( RR =0.29). Conclusions Shanxi exhibits cyclical mumps epidemics, with school-aged children as the high-risk population. School health management work should be carried out, and the surveillance of mumps in high-risk areas and the routine vaccination of two doses of mumps-containing vaccines for eligible children should be strengthened.

Irritable bowel syndrome (IBS) is characterized by abdominal pain associated with changes in defecation frequency and blood folate level. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. High-FODMAP diet could elicit or exacerbate IBS-associated bowel symptoms, which is inadequately recognized among gastroenterologists in China. Here we report an IBS case, focusing on the association between high-FODMAP diet and bowel symptoms and the intervention of low-FODMAP diet.