Objective To investigate the effects of tannic acid (TA) doping on the physicochemical properties, biocompatibility, in vitro osteogenic performance, and antibacterial activity of Brushite bone cement, and to evaluate its feasibility for bone defect repair. MethodsTA was incorporated into Brushite bone cement at concentrations of 0, 1.0, 3.0, 5.0, and 10.0 mg/g of solid powder, designated as Brushite, Brushite/TA-1, Brushite/TA-2, Brushite/TA-3, and Brushite/TA-4, respectively. The compressive strength and microstructure of each group were evaluated. The extracts of the bone cements were prepared and co-cultured with MC3T3-E1 cells. Cell proliferation was assessed using the cell counting kit 8 (CCK-8) assay. The cytotoxicity was observed by Calcein/propidium iodide live/dead cell staining. Cell adhesion was observed via scanning electron microscopy. After osteogenic induction, alkaline phosphatase (ALP) activity was measured and ALP staining was performed. The expression levels of osteogenic-related genes, including runt-related transcription factor 2 (Runx2), osteocalcin (OCN), osteopontin (OPN), collagen type Ⅰ (Col-Ⅰ), and integrin-binding sialoprotein (IBSP), were detected by real-time fluorescent quantitative PCR (qRT-PCR). The antibacterial activity of the bone cement against Escherichia coli was assessed using the inhibition zone method. ResultsCompared with the Brushite group, the Brushite/TA-3 and Brushite/TA-4 groups exhibited significantly increased compressive strength (P<0.05). TA doping resulted in a higher crystal content and a more regular and dense crystal arrangement. Regarding cytocompatibility, the Brushite/TA-3 group demonstrated the most pronounced enhancement of cell proliferation (P<0.05), whereas the Brushite/TA-4 group showed relatively lower cell proliferative activity (P<0.05). All groups exhibited low cytotoxicity with good cell viability. Cell adhesion density and pseudopodia extension were superior in all TA-doped groups compared with the Brushite group. Regarding osteogenic activity, after 14 days of osteogenic induction, ALP activity was higher in all TA-doped groups than in the Brushite group (P<0.05) in a dose-dependent manner. The relative expression of Runx2, OCN, OPN, Col-Ⅰ, and IBSP mRNA also increased to varying degrees in a dose-dependent manner compared with the Brushite group. Regarding antibacterial performance, only the Brushite/TA-4 group exhibited inhibitory effects against Escherichia coli, with an inhibition zone diameter of approximately 7 mm. ConclusionDoping with an appropriate concentration of TA (3.0-5.0 mg/g) improves the mechanical properties, cytocompatibility, and osteogenic activity of Brushite bone cement. A higher concentration (10.0 mg/g) confers antibacterial properties but may partially inhibit cell proliferation. TA-doped Brushite bone cement demonstrates good application potential in the field of bone defect repair.
ObjectivesTo analyze the balance of medical human resource allocation in Chengdu and to discuss the impact of human resource allocation structure on the hospital’s medical service capabilities, so as to provide a theoretical basis for the hospital to optimize the talent team structure.MethodsThe Moran’s index and Gini coefficient were used to evaluate the spatial aggregation and grade distribution difference of human resources allocation, respectively. The case mix index (CMI), the length of hospital stay, and the difficulty of surgery were used as outcome variables, and a multiple regression analysis model was established to explore the impact of human resource indicators on the hospital’s medical service capabilities.ResultsThe distribution of doctors showed an obvious spatial aggregation in Chengdu, and there was a positive spatial correlation (Moran’s Idoctor=0.290); the distribution of nurses had no obvious spatial aggregation (Moran’s Inurse=0.102). Under different medical service capacity segments, the Gini coefficient of doctors was 0.518, and the Gini coefficient of nurses was 0.576, both exceeding 0.5, indicating that the distribution of medical human resources in different levels of hospitals was considerably different. The regression results showed that the expansion of the quantity of senior title doctors and the proportion of medical care both could improve the hospital’s CMI. The increase in the quantity of doctors with senior titles also had a certain impact on improving the hospital’s surgical capabilities. The expansion of the proportion of medical care could lead to a slight increase in the length of patients' hospital stay.ConclusionsOptimizing the allocation structure of medical human resources in different regions and hospitals with different levels is an important task in the construction of a hierarchical diagnosis and treatment system. It is necessary to further integrate medical human resources throughout the whole city and strengthen personnel training and team building in primary health institutions. Hospitals at different levels should implement their own development positioning and further optimize their human resource allocation structure according to development needs. Tertiary hospitals should pay more attention to the cultivation of senior professional doctors, optimize the proportion of medical care, and improve the hospital’s medical service capabilities. The primary health institutions should pay attention to the comprehensive construction of medical personnel, and strengthen the development of the team of general practitioners, so as to achieve a comprehensive improvement of the city’s medical service capabilities.