ABSTRACT
Objective:To investigate the medicinal retention of different concentrations of melatonin in the bone tissue of type 2 diabetic osteoporosis (T2DOP) rats and explore to efficacy of improvement of the bone microstructure of T2DOP rats.Methods:A total of 95 SD rats were selected, 60 of which had intraperitoneal in jection of high-fat diet combined with low-dose streptozotocin establishing a T2DOP rat model. Two months later, 45 rats' model was determined to be successful by detecting blood glucose and insulin sensitivity index. 30 successful modelling and 30 normal SD rats were randomly selected for melatonin distribution experiment, and were divided into four groups according to the injected melatonin concentration, including modeling rat high concentration group (50 mg/kg), modeling rat low concentration group (10 mg/kg), normal rat high concentration group (50 mg/kg) and normal rat low concentration (10 mg/kg), and there were15 rats in each group. Each group was divided into 5 sub-groups according to the time point of sampling (5, 15, 30, 60, 120 min), 3 animals per group. The bone tissue of each group was pretreated, and then the melatonin drug distribution in the bone tissue was detected by high performance liquid chromatography (HPLC). Another 15 rats were successfully modeled, and were divided into T2DOP group, high melatonin group (50 mg/kg) and low melatonin group (10 mg/kg), 5 rats in each group. 5 normal SD rats were taken as controls (control group), and Micro-CT was used to detect changes in bone microstructure after 8 weeks of treatment with melatonin.Results:The results of the drug distribution experiment showed that after melatonin was injected intraperitoneally, there were drugs remaining in the bone tissues of the rats in each group. The drug concentration reached the highest after 30 min of administration, and significantly decreased after 120 min. Compared with the normal rat low concentration group, there was no significant difference in the drug concentration between the two groups at 5 time points. However, the drug concentration at the four time points of 5, 15, 30, and 60 min in the modeling rat high concentration group were 7.613±2.568 ng/ml, 13.983±2.262 ng/ml, 18.816±1.291 ng/ml, 6.172±1.962 ng/ml, 1.112±0.566 ng/ml, which were significantly different compared with normal rat high group. Micro-CT results showed that after 8 weeks of melatonin treatment, the bone density of the high concentration group was (205.72±28.41 g/cm 3) significantly lower than that in the low concentration group (223.63±35.41 g/cm 3), but both groups were significantly higher than the normal rat group (158.31±31.86 g/cm 3). Conclusion:Exogenous melatonin is distributed in bone tissue, and the drug absorption rate of T2DOP rats is higher. Meanwhile, there is no difference in the distribution of melatonin in bone tissue with different concentrations, and these two concentrations of melatonincan canimprove the bone microstructure of T2DOP rats.
ABSTRACT
Objective To compare the curative effect of conservative treatment and full thread hollow screw in the treatment of Ekrol 2 fracture of the fifth metatarsal bone.Methods From April 2013 to May 2015,42 patients with avulsion fractures of the fifth metatarsal basement of type 2 fractures in Ekrol division were treated in our hospital.23 patients underwent full thread hollow screw surgery (surgical treatment group),and there were 12 males and 11 females,with an average age of 43.4±9.2 years,and the fracture displacement length was 2.3±0.2 mm.19 patients treated with plaster fixation (conservative group),including 10 males and 9 females,with an average age of 45.7±8.9 years and fracture displacement length was 2.1±0.2 mm.During follow-up,X -ray examination was performed to evaluate the time of fracture healing and forefoot score of American Orthopaedic Foot and Ankle Society (AOFAS),visual analogue score (VAS) and quality of life questionnaire (SF-36) were compared between the two groups.Results All 42 patients were followed up for 12 to 24 months with an average of 18 months.At the latest follow-up,the fracture healing time of the surgical group was 9.3±2.0 weeks,with AOFAS score of 84.1±3.9,VAS score of 0.1±0.2,and the SF-36 score of 95.1±2.9 points,and the shortening of length after treatment was 2.1±2.5 mm;the average healing time of the conservative treatment group was 12.2±2.1 weeks,with the average AOFAS score of 84.2±4.2 points,and the average VAS score of 0.2±0.2 points,the average SF-36 score of 94.1 ±5.2 points,and the shortening of length after treatment was 0.4±2.5 mm.The results of each short-term score and the shortening of the length of the fracture after treatment was statistically significant.The results of the mid-and long-term scores showed no significant difference between the two groups;the fractures of both groups reached bone healing.3 cases of sural nerve stimulation occurred in the operation group,while 1 case occurred in the conservative group.Abnormal healing occurred in 2 cases of conservative treatment,and the fractures of the surgical treatment group were anatomic reduced.Conclusion Usingfull thread hollow screwfor the treatment of Ekrol 2 fracture of the fifth metatarsal bone is better than the conservative treatment in the short term,but there is no significant difference in the long-term effect.