Objective:To observe the effect of Risedronate on fracture healing in elderly patients with osteoporotic femoral intertrochanteric fracture.Methods:A retrospective case-control study was conducted on elderly patients with osteoporotic femoral intertrochanteric fractures in our hospital from June 2019 to June 2020.They were followed up regularly for 1 year after proximal femoral nail anti-rotation(PFNA)internal fixation.According to whether the patients took Risedronate during hospitalization, the patients were divided into two groups(PFNA internal fixation combined with Risedronate, 39 cases)and control group(PFNA internal fixation alone, 44 cases). The BMD values before and 1 year after operation were compared between the two groups.Harris score was used to evaluate hip function, Rush score was used to evaluate fracture healing, and the operation-related complications, adverse drug reactions and fractures in other parts were recorded.Results:The fractures of all patients healed 12 months after operation.There were no recurrent fractures in both groups during follow-up.The mean bone mineral density(BMD)T value in healthy side hip was(-2.83±0.46)in Risedronate group and(-3.16±0.42)in control group( t=-3.397, P=0.001). Among the total 83 patients, 39 patients in the Risedronate group had no obvious adverse reactions; 1 patient of 44 patients in the control group had obvious upper abdominal pain and discomfort, accompanied by nausea and lack of appetite.These symptoms improved after stopping the drug. Conclusions:Risedronate taken early after surgery does not affect fracture healing and can improve bone mineral density of healthy side hip.

Objective To detect the plasma concentrations of daptomycin in the left ventricle and right ventricle of rats by high-performance liquid chromatography-mass spectrometry(LC-MS/MS), and evaluate the therapeutic effect of daptomycin on left ventricular endocarditis. Methods Thirty-five healthy Sprague-Dawley (SD) rats were divided into a normal saline group (5 rats) and a daptomycin group (30 rats) according to the random number table method. The daptomycin group was subdivided into 6 subgroups according to the times of blood collection (0.25, 0.5, 1, 2, 4, 8 hours), with 5 rats in each subgroup. The normal saline group was given 4 mL/kg normal saline; the daptomycin group was injected with 50 mg/kg daptomycin into the tail vein. The blood samples from left ventricle and right ventricle were extracted at the corresponding time points, the plasma concentrations of daptomycin group were determined by high performance liquid chromatography-mass spectrometry (HPLC-MS) and the differences of left ventricular and right ventricular plasma concentrations were compared at different time points. The plasma in normal saline group was the blank plasma that was used for HPLC-MS methodological evaluation. Results There were no statistical significant differences between the left ventricle and right ventricle in plasma concentrations of daptomycin at 0.25, 0.5, 1, 2, 4, and 8 hours after administration (g/L: 2.67±0.30 vs. 2.77±0.31, 1.77±1.27 vs. 1.64±0.55, 1.35±0.40 vs. 1.36±0.41, 0.97±0.07 vs. 0.92±0.09, 0.73±0.16 vs. 0.65±0.18, 0.07±0.06 vs. 0.06±0.05, respectively all P > 0.05). Conclusion There are no significant differences between the left ventricle and right ventricle in plasma concentrations of daptomycin. It is speculated that daptomycin may have the same therapeutic effect on left endocarditis.