A human health risk assessment of rare earth elements through daily diet consumption from Bayan Obo Mining Area, China.

Rare earth elements (REEs) have been broad application in a range of industries, including the electronics industry, advanced materials, and medicine. However, health risks associated with REEs received increasing attention. 31 residents (16 males and 15 females) from Bayan Obo mining in Inner Mongolia, China, were enrolled in this study. In total, 677 food samples, the major human exposure matrices (drinking water and duplicate diets), and bio-samples (urine and blood) of 31 participants were obtained. The concentrations of REEs were measured to characterize their external and internal exposures, and the potential health risk of exposure to REE through the ingestion route was analyzed. The results revealed that the detection rate in blood samples (100%) is higher than in urine (32.86%), and only a few REEs were detected in water samples (8.06%), the urine concentrations were considerably lower than in blood. Exposure to REEs through drinking water was considered negligible compared to food intake. Lanthanum and cerium were the most concentrated REEs in food samples. Health risks were calculated based on a dose-response model, the total hazard quotients (THQ) values for all food groups were within normal levels, and the Monte Carlo simulation results show that the 5th, the 50th, and the 95th percentile values of HI were found as 1.45 × 10-2, 3.52 × 10-2, and 9.13 × 10-2, respectively, neither exceeds the threshold, indicating low health risks associated with food intake exposure for this area. The sensitivity results suggest that underweight people are at higher risk, cerium, lanthanum, and yttrium concentrations, and food intake contributes more to health risks. The use of probability distribution methods can improve the accuracy of the results. The cumulative health risk through food intake is negligible, and further attention should be paid to the health risk induced by other routes of exposure to REEs by the local residents.

Performance assessment of medical service for organ transplant department based on diagnosis-related groups: A programme incorporating ischemia-free liver transplantation in China.

Background: In July 2017, the first affiliated hospital of Sun Yat-sen university carried out the world's first case of ischemia-free liver transplantation (IFLT). This study aimed to evaluate the performance of medical services pre- and post-IFLT implementation in the organ transplant department of this hospital based on diagnosis-related groups, so as to provide a data basis for the clinical practice of the organ transplant specialty. Methods: The first pages of medical records of inpatients in the organ transplant department from 2016 to 2019 were collected. The China version Diagnosis-related groups (DRGs) were used as a risk adjustment tool to compare the income structure, service availability, service efficiency and service safety of the organ transplant department between the pre- and post-IFLT implementation periods. Results: Income structure of the organ transplant department was more optimized in the post-IFLT period compared with that in the pre-IFLT period. Medical service performance parameters of the organ transplant department in the post-IFLT period were better than those in the pre-IFLT period. Specifically, case mix index values were 2.65 and 2.89 in the pre- and post-IFLT periods, respectively (p = 0.173). Proportions of organ transplantation cases were 14.16 and 18.27%, respectively (p < 0.001). Compared with that in the pre-IFLT period, the average postoperative hospital stay of liver transplants decreased by 11.40% (30.17 vs. 26.73 days, p = 0.006), and the average postoperative hospital stay of renal transplants decreased by 7.61% (25.23 vs.23.31 days, p = 0.092). Cost efficiency index decreased significantly compared with that in the pre-IFLT period (p < 0.001), while time efficiency index fluctuated around 0.83 in the pre- and post-IFLT periods (p = 0.725). Moreover, the average postoperative hospital stay of IFLT cases was significantly shorter than that of conventional liver transplant cases (p = 0.001). Conclusion: The application of IFLT technology could contribute to improving the medical service performance of the organ transplant department. Meanwhile, the DRGs tool may help transplant departments to coordinate the future delivery planning of medical service.

A population pharmacokinetic model of vancomycin for dose individualization based on serum cystatin C as a marker of renal function.

OBJECTIVES: This study aimed to establish a vancomycin population pharmacokinetics (PPK) model based on serum cystatin C and to optimize dosing for achieving targeted steady-state trough concentrations (Css ) of 10-15 and 15-20 mg/l. METHODS: Patients aged ≥18 years were prospectively enrolled. A vancomycin PPK model was built with glomerular filtration rate (GFR) as a renal covariate estimated by cystatin C. A new group of patients were used for external evaluation. PPK analysis and Monte Carlo simulations were performed using nonlinear mixed effect modelling programme. KEY FINDINGS: Two hundreds of patients with 514 samples were included. The final model was CL (L/h) = (5.07 × (GFR/105.5)0.524 × (AGE/48.5)-0.309 × (WT/60)0.491 ); V (l) = 46.3. Internal and external evaluations demonstrated good stability and predictability. The average probability of target attainment (PTA) of optimal dosing regimens for targeted Css achieving 10-15 and 15-20 mg/l were 51.2% and 40.6%, respectively. An average PTA ≥71% for targeted concentration of 10-20 mg/l was obtained. CONCLUSIONS: A vancomycin PPK model with cystatin C as the renal marker has good stability and predictability. The new proposed dosing regimens were predicted to achieve a good PTA.