Objective To evaluate the efficacy of intrathecally administered monosialoganglioside (GM-1)for treatment of bupivacaine spinal anesthesia-induced neurotoxicity to rat spinal cord.Methods Adult male Sprague-Dawley rats,weighing 280-300 g,in which the intrathecal catheter was successfully inserted into the L3,4 intervertebral space and advanced toward the tail,were randomly divided into 4 groups (n =36 each):sham operation group (group S),GM-1 group,bupivacaine group (group B) and bupivacaine + GM-1 group (group BG).In B and BG groups,the rats received 5％ bupivacaine 20 μl via the intrathecal catheter 3 times at 1.5-hour intervals.GM-1 20 μg was injected intrathecally 24 h later once a day for 7 days in BG and GM-1 groups.Before bupivacaine injection and on days 1,3,5,7,14 and 28 after bupivacaine injection (T0-T6),tail flick latency (TFL) was measured,MPE (percentage of maximal possible effect) was calculated,and the locomotor recovery was evaluated using the Basso,Beattie,Bresnahan (BBB) Locomotor Rating Scale.Then six rats were randomly chosen and sacrificed in each group.Spinal cord was removed for histopathologic examination (with light and electronic microscope) and for determination of caspase-3 protein and mRNA expression (by immuno-histochemistry and RTPCR).The pathological changes of the spinal cord were scored.Results Compared with S and GM-1 groups,MPE,pathological scores,and caspase-3 protein and mRNA expression were significantly increased and BBB score was decreased at T1-6 in group B (P ＜ 0.05),and MPE was increased at T1-5 (P ＜ 0.05) and returned to the baseline value at T6 (P ＞ 0.05) and pathological scores,and caspase-3 protein and mRNA expression were significantly increased and BBB score was decreased at T1-6 in group BG (P ＜ 0.05).There were no significant differences in each parameter at each time point between S and GM-1 groups (P ＞ 0.05).Compared with group B,MPE and caspase-3 protein and mRNA expression were significantly decreased at T2-6,pathological scores were decreased at T3-6,and BBB score was increased at T4-6 in group BG (P ＜ 0.05).The pathological changes of spinal cord tissues were obvious at T1-6 in group B and at T1-3 in group BG,but the changes gradually recovered at T4-6 in group BG.Conclusion Intrathecally administered GM-1 has therapeutic effect against bupivacaine spinal anesthesia-induced neurotoxicity to rat spinal cord,and inhibition of neuronal apoptosis in the spinal cord may be involved in the underlying mechanism.

Objective:To analyze the clinical characteristics of patients with bisphosphonates related atypical femoral fractures(AFFS), thereby to facilitate early diagnosis.Methods:The clinical manifestations, biochemical indexes, imaging features and treatment follow-up of AFFS patients who were diagnosed in the Department of Osteoporosis and Bone Disease, the Sixth People′s Hospital Affiliated to Shanghai Jiaotong University from 2011 to 2019 were analyzed retrospectively, and the literature was reviewed.Results:A total of 5 cases of atypical bisphosphonate related femoral fractures were collected, all of them were female, with an average age of 68 years. All the 5 patients were treated with alendronate. Three patients were treated with 70 mg/week throughout the course, and two patients were treated with 10 mg/day at first, and changed to 70 mg/week later. The average course of treatment was 8.7 years, ranging from the shortest 5 years to the longest 17 years. Among the 5 cases, the shortest onset time was 3 years after taking medicine, and the longest was 16 years. The clinical features are as follows: all patients had prodromal pain before fracture which was characterized as dull except for case 4. Case 1 was bilateral thigh pain, the rest were unilateral thigh pain, which began to appear within 2-3 years before fracture. X-ray plain film showed thickening of the lateral bone cortex; radionuclide bone scan(ECT) showed active bone metabolism in the affected area. The abnormal manifestations of ECT were earlier than X-ray and MRI. The recognition of these features is helpful to the early diagnosis of AFFS. All 5 patients stopped bisphosphonates immediately, and continued to take calcium tablets. Active vitamin D was added to 4 cases. One case of incomplete fracture was treated conservatively with Teriparatide for one year, which was helpful to deter it from becoming complete fracture. 4 cases of complete fracture were treated with reduction and fixation, and all healed.Conclusion:Long-term use of bisphosphonates can increase the risk of AFFS. Strengthening the risk assessment during use can reduce the incidence of such fractures. Early diagnosis and reasonable treatment can improve the prognosis.

Objective:To evaluate the clinical value of prenatal molecular diagnostic technology in preventing hereditary diseases through analysis of prenatal diagnostic characteristics in 22 monogenic skeletal disorders pedigrees.Methods:This study retrospectively analyzed prenatal molecular diagnostic results of 22 pedigrees with monogenic skeletal disorders who were admitted to Department of Osteoporosis and Bone Diseases in our hospital from January 2014 to July 2021.Results:Among 22 pedigrees, there were 10 pedigrees with X-linked hypophosphatemic rickets due to PHEX gene mutations, in which 8 fetuses were found to carry pathogenic variants; 6 pedigrees with osteopetrosis, including 3 cases of CLCN7 gene mutation, 2 TCIRG1 gene mutation, and 1 CTSK gene mutation, were detected to have 2 affected fetuses and 1 carrier. There were 4 cases of osteogenesis imperfecta, including 2 cases of COL1A1 gene mutation, 1 case of COL1A2 gene mutation, and 1 case of SERPINF1 gene mutation, in which 1 affected fetus and 1 carrier were found; only one case of osteoarthritis with mild chondrodysplasia caused by COL2A1 gene mutation was found to harbor pathogenic variant in fetus; 1 case of hypophosphatasia due to ALPL gene mutation was not detected to carry pathogenic variant in fetus. By the time of follow-up, all 12 affected fetuses were terminated, and the remaining 10 fetuses except for one case still in pregnancy were born in good condition.Conclusion:Prenatal molecular diagnosis may confirm whether the fetus carries pathogenic variants at the first and second trimesters. For monogenic skeletal disorders that comply with Mendel′s law of separation, prenatal diagnosis can be determined by calculating the probability of recurrence of offspring. In addition, for families with de novo mutations in the offspring, it is necessary to pay attention to whether there are mosaic mutations in the parents.