Objective:To analyze the differential protein expression between multidrug-resistant human osteosarcoma MG-63/DXR100 and its parental cell line by differential in-gel electrophoresis,so as to lay a foundation for exploring the mechanism of multidrug resistance(MDR) of osteosarcoma.Methods:Multidrug-resistant clone of human osteosarcoma MG-63 was established by stepwise exposure to increasing doses of doxorubicin(DXR).The total proteins of the above two cell lines were separated with two-dimensional electrophoresis.The proteins of differential expression(increased or decreased by more than 30%) were analyzed with image scanning and DeCyder software.Then they were identified in MALDI-TOF Pro and Mascot database.Results:Thirty proteins with differential expression were identified by proteomic analysis,and 18 of them were further identified by MALDI-TOF Pro.Five protein spots were successfully identified:matrix metalloproteinases 1(MMP1) related with tumor cell metastasis,alcohol dehydrogenase(ADH6) with function of detoxication,FERM domain containing protein 3(FRMD3) which belongs to anti-oncogenes and two agnoproteins composed of 128 and 300 amino acid residues.MMP1,ADH6 and the two agnoproteins were over-expressed in MG-63/DXR100 group,and FRMD3 expression was lower than that in the MG-63 group.Conclusion:Five proteins including MMP1,ADH6,FRMD3 and two agnoproteins have been found abnormally expressed in MDR osteosarcoma cells by differential in-gel electrophoresis;they might participate in MDR of osteosarcoma.

Objective To explore the effects of semiconductor laser on proliferation of the multidrug-resistant model of human osteosarcoma cell line(ROS-732).Methods Four test groups and one control group were set up.The test groups were divided into A,B,C and D groups according to the irradiation time(output power was 200 mW).The time of laser irradiation of A,B,C and D groups were 5,10,20 and 40 min,repectively.The control group(E) wasn′t treated with laser irradiation.MTT method was used to observe the proliferation of R-OS-732,and the morphological changes of the cells were observed by inverted microscope.Results The survival rates of cells in all test groups under condition of semiconductor laser irradiation with 200 mW output power and 532 nm weavlength,compared with control group(P

Objective: To investigate the curative effects of apoptin on the multidrug-resistant model, of human osteosarcoma cell line (R-OS-732). Methods: 363 bpVP 3 gene was cloned into the vector pIRES1 and the recombinant eukaryon expression vector pIRVP3 was transfected into R-OS-732 cells with liposome. The expression of apoptin gene at transcription level was proved by RT-PCR. The pathological changes of the cells was observed by light microscope and electronmicroscope. The transfected R-OS-732 cells were collected after 48 hours. The genomic DNA extracted from the cells was observed by agarose gel electrophoresis. The apoptosis rate of the cells was analysed by flow cytometry. Results: The expression of apoptin gene at transcription level had been proved by RT-PCR. The construction changes of the two groups were obviously different under light microscope: most of R-OS-732 cells in the transfected group existed in form of being away from the bottom of the culture dish after 24 hours, in form of apoptosis after 48 hours and in form of necrosis after 72 hours; but those cells in the controlled group grow luxuriantly. And under electronmicroscope there was much change of cell nucleus between the two groups. DNA ladder of the transfected cells was observed through agarose gel electrophoresis only one band was observed in the controlled group; but bands of fragmented DNA observed in ositive control group. Flow cytometry analysis showed that the apoptosis rate of the cells in the transfected group was relatively higher than that of the controlls( P

Objective To compare the curative effect and biomechanical performance of cannulated compression screw (CCS) and dynamic hip screw-blade (DHS-B) in the treatment of patients with femoral neck fracture.Methods Between February 2010 and February 2014,102 patients with femoral neck fracture were treated with CCS or DHS-B at our department.They were 54 males and 48 females,aged from 15 to 86 years.There were 30 subcapital fractures,51 transcervical ones and 21 base ones.CCS was used in 60 patients and DHS-B in 42.In-hospital data were collected retrospectively to compare the curative effects in 2 groups.Furthermore,femoral neck fracture models were established using 12 adult cadaveric femoral specimens.The 12 models were randomized into 2 equal groups (n =6).Group A was subjected to fixation by 3 CCSs and group B to fixation by DHS-B.The 2 groups were compared in terms of axial loading test,rotation test and destructive axial loading test.Results The operation time (59.4 ± 20.2 min),incision size (4.1 ±0.6 cm) and intraoperative blood loss (25.9 ±9.9 mL) in the CCS group were significantly less than those in the DHS-B group (88.6±22.9 min,12.1 ±1.2cmand 156.7±107.1 mL) (P ＜0.05).The Harris hip score for the DHS-B group (91.9±9.8) was significantly higher than that for the CCS group (87.2 ± 9.2) (P ＜ 0.05).There were no significant differences between the 2 groups in hospital stay,partial weight-bearing time,or postoperative complications (P ＞ 0.05).At 500 N vertical loading,the stress values at both medial and lateral sides of the femur in group A were significantly smaller than those in group B (P ＜ 0.05).There were no significant differences between groups A and B in the average sinking displacement of femoral head or the torque at a torsion angle of 6° (P ＞ 0.05).The maximum load in group A (2,135 ±120 N) was significantly smaller than that in group B (2,986 ± 98 N) (P ＜ 0.05).Conclusion In treatment of femoral neck fracture,DHS-B fixation is obviously superior to CCS fixation,because the former is in better agreement with the femoral biomechanical property,and performs better in anti-rotation and anti-compression,leading to better functional recovery of the affected hip.

Objective: To investigate the mode of cell death caused by NDV strain Changchun and NDV strain Siping. Methods: Plaque formation, cell suppression test, gel electrophoresis, and TUNEL assay were used after the cells were infected by NDV. Results: The apparently pathological changes were observed in chicken embryo fibroblasts, BHK, Hela, Hep 2, HCT and OS 732 tumor cells, but not in Wish cells. The higher suppressed effect on tumor cells was found in the NDV strain Changchun than that in the NDV strain Siping. There was no dose effect relationship between NDV and tumor cell suppression, only optimum dose NDV could cause maximal tumor cells inhibitory effect. Conclusion: The mode of cell death might be different after infection of NDV. The NDV strain Changchun killed tumor cells mainly through apoptosis, while the NDV strain Siping killed tumor cells mainly through necrosis. \[

Objective:To investigate the clinical efficacy of TiRobot-assisted minimally invasive percutaneous screw fixation for pelvic fractures.Methods:The clinical data of 44 patients with pelvic fracture were retrospectively analyzed who had undergone TiRobot-assisted minimally invasive percutaneous screw fixation from May 2018 to April 2021 at Department of Orthopedic Traumatology, The First Hospital of Jilin University. There were 30 males and 14 females, aged from 11 to 78 years (average, 40.6 years). According to the Tile classification, there were 20 type C1 fractures, 23 type C2 fractures and one type C3 fracture. The time from injury to operation averaged 8.2 days (from 1 to 41 days). The minimally invasive percutaneous screw fixation was assisted by the orthopaedic TiRobot in all patients. Operation time, fluoroscopy time, reduction quality, complications and functional recovery at the final follow-up were recorded and analyzed.Results:A total of 96 screws were implanted in this cohort. The total fluoroscopy time ranged from 17 to 66 s, with an average of 17.8 s for each single screw. The operation time ranged from 50 to 355 min, averaging 179.7 min. According to the Matta criteria, the reduction quality was rated as excellent in 36 cases, as good in 5 and as fair in 3, yielding an excellent and good rate of 93.2%(41/44). All the 44 patients were followed up for 6 to 42 months (average, 20.4 months). The fracture healing time ranged from 2 to 6 months, averaging 3.3 months. The Majeed scores at the final follow-up ranged from 51 to 100 points (average, 83.7 points); there were 28 excellent, 8 good, 7 fair and one poor cases, giving an excellent to good rate of 81.8% (36/44). Follow-up found no such complications as iatrogenic neurovascular injury, incision infection, malunion, implant loosening or fracture re-displacement in all the 44 patients.Conclusion:TiRobot-assisted minimally invasive internal fixation can result in fine clinical efficacy for pelvic fractures, showing advantages of accuracy, minimal invasion and safety.

Objective:To investigate the clinical efficacy of robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation in the treatment of pelvic fracture.Methods:A retrospective analysis was conducted on 28 cases with pelvic fractures treated with robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation from May 2018 to November 2022. There were 19 males and 9 females, with an average age of 43.4±16.9 years (range, 14-74 years). There was 1 case of B1 type, 1 case of B2 type, 4 cases of B3 type, 10 cases of C1 type, 9 cases of C2 type and 3 cases of C3 type by Tile classification. All the cases were treated with closed reduction, LC-II external fixation for the anterior lesions and robot-assisted minimally invasive sacroiliac screw fixation for the posterior lesions. The operation time, fluoroscopy time and excellent rate of screw placement were recorded. The quality of fracture reduction was evaluated by Matta's criteria, and the clinical effect was evaluated by Majeed score.Results:All the 28 cases successfully underwent the surgery. In 11 cases the fractures were reduced by the pelvic unlocking closed reduction device while in the other 17 cases manual reduction was applied. In this cohort, 43 screws were implanted. All the screw positions reached level I by Gras grading. The average fluoroscopy time was 16.3±5.2 s (range, 9-31 s) per screw. The average operation time was 154.9±54.7 min (range, 55-226 min). According to the Matta's criteria, the reduction was rated as excellent in 19 cases, good in 7 cases, fair in 2 cases, yielding an excellent or good rate of 93% (26/28). No iatrogenic neurovascular injury was found in all the 28 patients. The average follow-up was 18.3±7.3 months (range, 4-31 months). The fractures healed at 3.6±1.1 months (range, 2-6 months) after the surgeries. At the final follow-up, the results of the Majeed scores were rated as excellent in 13 cases, good in 11 cases, fair in 3 cases and poor in 1 case, with an excellent or good rate of 86% (24/28).Conclusion:The technique of robot-assisted minimally invasive sacroiliac screw fixation combined with LC-II external fixation used in the treatment of pelvic fracture showed good clinical results.

Accurate classification of the acetabular injuries and appropriate treatment plan are great challenges for orthopedic surgeons because of the irregular anatomical structure of the acetabulum and aggregation of important vessels and nerves around it. Letournel-Judet classification system has been widely applied to classify acetabular fractures. However, there are several limitations, including incomplete inclusion of fracture types, difficulty in understanding and insufficient guidance for surgical treatment, etc. Serious complications such as traumatic arthritis are common due to wrong classification and diagnosis and improper selection of surgical strategy, which brings a heavy burden to the society and families. Three-column classification, based on anatomic characteristics, has advantages of containing more fracture types and being easy to understand, etc. To solve the problems existing in the diagnosis and treatment process based on Letournel-Judet classification, achieve accurate diagnosis and treatment of patients with acetabular fractures, and obtain satisfactory prognosis, the Orthopedic Trauma Emergency Center of Third Hospital of Hebei Medical University and the Trauma Orthopedic Branch of the Chinese Orthopedic Association organized experts from relevant fields to formulate the Expert consensus on the accurate diagnosis and treatment of acetabular fractures based on three-column classification ( version 2023) in terms of principles of evidence-based medicine. Based on the three-column classification, 15 recommendations were proposed, covering the diagnosis, treatment, complication prevention and management, etc, so as to provide reference for accurate diagnosis and treatment of acetabular fractures.