ObjectiveTo investigate the feasibility and effectiveness of proximal tibial hemiprosthesis replacement in the first stage and prosthesis revision in the second stage in reducing the risk of length discrepancy of limbs in children with proximal tibial osteosarcoma.MethodsBetween 2009 and 2013, 3 children with conventional osteosarcoma at the proximal tibia (stage ⅡB) were treated. There were 2 boys and 1 girl. They were 12, 13, and 13 years old, respectively. After 4 courses of preoperative chemotherapy, the proximal tumor segmental resection and proximal tibial hemiprosthesis replacement were performed. Then the patients underwent prosthetic revision in the second stage when they were 20, 17, and 17 years old, respectively.ResultsAll patients successfully completed two stages of operations. The length discrepancy of lower limb after the second stage operation were 19, 7, and 21 mm, respectively. Three patients were followed up 13, 3, and 27 months after the second stage operation, and the lower extremities functions were satisfactory. The Musculoskeletal Tumor Society (MSTS) score was 26, 27, and 25, respectively.ConclusionThe proximal tibial hemiprosthesis replacement in the first stage combined with prosthesis revision in the second stage for treating the proximal tibia osteosarcoma in children can keep the distal femur growth ability, reduce the length discreapancy of lower limb, and obtain satisfactory stability and good function.
Objective
To investigate the effect of ursolic acid on the proliferation and apoptosis of human osteosarcoma cell line U2-OS and analyze its mechanism.
Methods
Human osteosarcoma cell line U2-OS was divided into 4 groups, which was cultured with ursolic acid of 0, 10, 20, and 40 μmol/L, respectively. At 0, 24, 48, and 72 hours after being cultured, the cell proliferation ability was detected by cell counting kit 8 (CCK-8). At 48 hours, the effects of ursolic acid on cell cycle and apoptosis of U2-OS cells were measured by flow cytometry. Besides, the expressions of cyclin D1 and Caspase-3 were detected by real-time fluorescent quantitative PCR and Western blot.
Results
CCK-8 tests showed that the absorbance (A) value of each group was not significant at 0 and 24 hours (P>0.05); but the differences between groups were significant at 48 and 72 hours (P<0.05). Flow cytometry results showed that, with the ursolic acid concentration increasing, the G1 phase of U2-OS cells increased, the S phase and G2/M phase decreased, and cell apoptosis rate increased gradually. There were significant differences between groups (P<0.05). Compared with the 0 μmol/L group, the relative expressions of cyclin D1 mRNA and protein in 10, 20, and 40 μmol/L groups significantly decreased (P<0.05); whereas, there was no significant difference in relative expression of Caspase-3 mRNA between groups (P>0.05). However, with the ursolic acid concentration increasing, the relative expressions of pro-Caspase-3 protein decreased and the relative expressions of activated Caspase-3 increased; there were significant differences between groups (P<0.05).
Conclusion
Ursolic acid can effectively inhibit the proliferation of osteosarcoma cell line U2-OS, induce the down-regulation of cyclin D1 expression leading to G0/G1 phase arrest, increase the activation of Caspase-3 and promote cell apoptosis.
ObjectiveTo analyze the ultrasonic manifestations of myxoid liposarcoma (MLS) in soft tissues.MethodsWe retrospectively analyzed the ultrasonic characteristics of 10 cases of soft tissue MLS which were pathologically confirmed between January and June 2006. Results Ultrasonic manifestations: 8 cases occurred in muscles and 2 in subcutaneous tissues and muscles; the maximum mass diameter was (71.1±39.4) mm; 10 cases had clear border, 8 had regular shape, and 9 had posterior echo enhancement; 10 cases were all solid masses with mucous liquid zone (9 cases had mainly weak echo, among which 5 had strong echo areas; 1 case had mainly strong echo); bloodstream grade: 3 cases belonged to level 0, 3 level Ⅰ, 2 level Ⅱ, and 2 level Ⅲ. Pathologic findings: 2 cases had low differentiation; 1 case was a mixture of MLS and atypical lipoma with mainly strong ultrasonic echo; the rest 7 cases had middle or high differentiation.ConclusionsUltrasonic manifestations of soft tissue MLS are mostly large masses in the muscular layer with clear border, regular shape, posterior echo enhancement and mucous liquid zone. Various degrees of strong echo zone exist in the masses. Bloodstream and mucous liquid zone are correlated with differentiation degree, and ultrasonic manifestations can be influenced if other factors exist.
