BACKGROUND:Nano-hydroxyapatite/col agen combined with mononuclear cel s can promote the growth of a variety of stem cel s to induce the formation of new bone and vascularization, final y inducing osteogenesis.
OBJECTIVE:To investigate the feasibility of bone marrow mononuclear cel s combined with the nano-hydroxyapatite/col agen for repair of mandibular defects in a rabbit.
METHODS:Twenty-seven New Zealand white rabbits were selected to prepare bilateral mandibular bone defect models, and then divided into three groups. In experiment group, bone marrow mononuclear cel s combined with the nano-hydroxyapatite/col agen were implanted into mandibular defects;in control group, nano-hydroxyapatite/col agen scaffold was implanted;and in blank control group, nothing was implanted. Tissue specimens were prepared at weeks 4, 8, 12 for gross observation, imaging analysis, hematoxylin-eosin staining and scanning electron microscope.
RESULTS AND CONCLUSION:The imaging examination and histological staining showed that the bone quality and healing degree in the experimental group was better than those in the other groups. Scanning electron microscope showed that better histocompatibility and no inflammation reaction in the experimental group. Dental CT data showed that the experimental group had better repair effect than the other groups (P<0.05). These findings indicate that bone marrow mononuclear cel s combined with the nano-hydroxyapatite/col agen have capacity of bone induction and bone formation, which can be used to repair mandibular defects.

ObjectiveTo study the effect of lentivirus-mediated microRNA-21 RNAi on biological behaviors in human hepatic cancer cells.MethodsMicroRNA-21 specific siRNA gene was synthesized and cloned into the recombinant lentiviral vector,pGCSIL-GFP.HepG2 cells were infected by microRNA-21 siRNA recombinant lentivirus (miR-21-siRNA-Ⅳ).The HepG2 cells were devided into SI group,NC group and N group in vitro.The expression of the targets of miR-21 was detected by RT-PCR.Cell growth was analyzed by MTT assay.The invasion was dectected by tmnswell method.Apoptosis was detected by Hoechst33258.BALB/c nude mice were randomly divided into SI group and NC group.The growth of transplant tumors in BALB/c nude mice were observed.Results ( 1 ) The expression level of miR-21 was inhibited significantly by miR-21-siRNA-lⅣ.(2) The proliferation of HepG2 was also markedly suppressed in MTT at the 96 h point ( P =0.0031,P ＜ 0.05 ).(3) The number of cells that migrated through the chamber of SI group decreased ( P =0.0004,P ＜ 0.05 ).(4) The cell apopotosis in SI group increased markedly.In addition,the caspase 3 mRNA significantly increased ( P =0.0002,P ＜ 0.05 ).( 5 ) Tumor growth curve was not statistically different between groups ( P =0.0002,P ＜ 0.05 ).ConclusionsMicroRNA-21 specific siRNA suppresses the proliferation and migration of HepG2 cells and induces tumor cell apoptosis inhibiting the growth of transplanted tumor in Balb/c nude mice.

Objective To investigate the therapeutic effect and mechanism of total flavone of haw-thorn leaf ( TFHL) on p38MAPK signaling pathway and inflammation factors in rats brain with chronic cere-bral ischemia.Methods SPF class healthy male SD rats were randomly divided into sham group, model group,TFHL group and Ginkgo leaf group( 12 rats in each group) .Permanent bilateral carotid artery ligation was used to prepare chronic cerebral ischemia model.Morris water maze method was used to evaluate learn-ing and memory abilities of rats.Immunohistochemistry and Western blot methods were used to measure the expression of caspase-3 and p38MAPK proteins.ELISA method was used to measure the amounts of TNF-αand IL-1βin hippocampal tissue.Results Compared with the model group,TFHL treatment (36 d) can im-prove learning and memory capabilities of vascular dementia rats,shorten the escape latency ( TFHL group(10.01±2.85) s vs Model group (19.54±6.12) s, P<0.05) and the course of searching platform(TFHL group(2.6044±0.3219)m vs model group(3.3502±0.6231)m, P<0.05),increase the numbers of crossing the platform (TFHL group(5.17±2.12) times vs Model group (3.96±1.34) time,s P<0.05) and the platform quadrant swimming distance percentage (TFHL group(48.22±7.39)%vs model group (33.42±5.32) %, P<0.01).The number of caspase-3 positive cells in the hippocampus significantly reduced (TFHL group(1.677 ±0.164) vs Model group (2.387±0.171), P<0.05),the expression level of P38MAPK protein (TFHL group (0.0161±0.0003) vs Model group (0.0254±0.0018), P<0.05),TNF-α(TFHL group(19.61±3.61) ng/10 mg vs Model group (27.82±6.57) ng/10 mg, P<0.01)and IL-1β(TFHL group(24.41±2.56) ng/10 mg vs Model group (29.43±5.26) ng/10 mg, P<0.05) were significantly decreased.Conclusion TFHL plays a protective role in nerve function of the chronic cerebral ischemia rats.The mechanism of its antia-poptosis might be associated with the activation of P 38MAPK signaling pathway,inflammation and the apoptosis of neurons in the brain.

Osteosarcoma is the most common aggressive malignancy of bone.Recent studies have discovered that exosomes can mediate intercellular transfer of biologically active molecules such as RNAs, dsDNA, and miRNAs.The specific membrane struc-ture and contents of exosomes are widely engaged into the exchange of material and information among tumor cells, which play an im-portant role in regulating the tumor microenvironment of osteosarcoma, mediating the expression of Wnt/β-catenin, TGF-βsignaling and inducing tumor cell immune escape.Exosomes derived from osteosarcoma cells with antigen-presenting cells cause significant anti-tumor effect by activating the immune response.Research on exosomes has therefore opened up a new avenue for treatment of osteosar-coma.In this article we review the role of exosomes in pathogenesis of osteosarcoma and its potential application on diagnosis and treat-ment of osteosarcoma.

Objective:To explore the inflammatory responses of macrophages treated with Helicobacter pylori. Methods:Cytokines IL-23,IL-10,TNF-α and IL-8 in cell culture supernatant of macrophages stimulated with Helicobacter pylori were determined by ELISA kits,and the expression of intracellular proteins NOS2 and COX2 in Helicobacter pylori treated macrophages was analyzed by Western blot. Then,the apoptosis of Helicobacter pylori stimulated macrophages was detected by flow cytometry. Results:The secretion of cytokines IL-23,IL-10,TNF-α and IL-8 in the culture supernatant of Helicobacter pylori treated macrophages increased significantly (P<0. 05),and the expression of NOS2 and COX2 was enhanced evidently(P<0. 05). Meanwhile,helicobacter pylori could induce the apoptosis of macrophages obviously ( P<0. 03 ) . Conclusion: The inflammatory responses of macrophages treated with Helicobacter pylori would be promoted to inhibit or kill Helicobacter pylori,furthermore,Helicobacter pylori could induce the apotosis of macropha-ges.

s:Bone allografts have been successfully used in repairing bone defect caused by tumor, infection or trauma. The mechanism of bone-healing of allografts has been widely studied. The article reviews the factors affecting the bone-healing of allografts.

Objective To introduce a new design of interlocking system which is easy in use, makes the distal fracture fragments well aligned and rigidly fixated, reduces exposure to radiation for the surgeon and patient, and allows for a decrease in operating time. Methods The new interlocking system was designed to be a self-locking nail with bevels (b-SLN). According to the bevel principle, the axial force of the nail should be turned into a transverse force so as to control the transverse nail's movement. 10 dry-bone simples were made into the fracture model of the middle-femur to test the prototype nail. The retention of the nail in the intramedullary cavity was evaluated by the radiogram. The mechanical properties of a simulated model of single leg loading were tested on the instron-1342 type MTS. Results The prototype nail performed well as designed. The process was stable and reliable. The retention in the intramedullary cavity was fine. The shearing force between the transverse nail and main nail was enough to cut anything around them. The mechanical properties of b-SLN were similar to those of the Grosse-Kempf nail, better than auto fork compress locked intramedullary nail, and much better than MHUA nail and Ender's nail. Conclusions The structure of b-SLN is simple and reliable. There is no focus-point under stress. Its biomechanic properties are satisfactory. It is easy to use with no need of fluoroscopes in the operating theatre.

Objective To investigate the stimulative effects of CollagenⅠon the increased adhesion of rabbit bone marrow stromal cells (BMSCs), cytoskeleton actin organization and intracellular free Ca~(2+) concentration. Methods The third generation BMSCs isolated from mature rabbits were cultured at different initial concentrations on cover-slice coated by collagenⅠin RPMI1640 containing 10% fetal calf serum, and cultured on the same kind of cover-slice untreated with collagenⅠas control. The cells adhesive behavior at different times was assessed. Cellular actin organization was described as either typeⅠor typeⅡcells. In general, typeⅠcells are round and represent a preliminary stage of actin assembly, while typeⅡcells are elongated with organized actin fiber network. At the same time intracellular free Ca~(2+) concentration was measured by using calcium fluorescent probe Fluo-3/AM and laser confocal microscope. Results We found more typeⅡcells in BMSCs cultured with collagen typeⅠsix hours after culture than in the control group. At 12 hours 89% of the BMSCs were typeⅡcells, while only 55% were typeⅡcells in the control group. This indicated active cellular actin organization after being modified by collagen typeⅠ. We also found that the BMSCs cultured with collagen typeⅠincreased intracellular free Ca~(2+) concentration in monolayer culture. Conclusions CollagenⅠis effective in promoting the cellular adhesion, which suggests that a kind of internal relationship or cross-talk may exist between cellular actin organization, intracellular free Ca~(2+) concentration and cell adhesion. Further study, however, is needed.

Objective The periacetabular tumor has a low rate of incidence, but its special location poses a challenge to clinical treatment.The aim of this study was to discuss the methods, effects, and complications of surgical treatment of periacetabular tumors. Methods We retrospectively analyzed the clinical data of 36 cases of periacetabular tumor surgically treated in our depart-ment, including 21 males and 15 females, aged 15 to 64 (45.2 ±6.3) years.Among them, there were 8 cases of benign tumor (4 ca-ses of simple bone cyst, 1 case of desmoplastic fibromas, 1 case of osteofibrous dysplasia, and 2 cases of hemangioma) and 28 cases of malignant tumor (5 cases of osteosarcomas, 12 cases of chondrosarcomas, 2 cases of giant cell tumor of the bone, 1 case of malignant chondroblastoma, 2 cases of malignant fibrohistiocytoma, and 5 cases of metastatic tumor of the bone).The benign cases received sim-ple tumor resection plus bone graft and steel plate system internal fixation, while malignant cases underwent reconstruction by combined pedicle screw fixation system with bone cement. Results No patients died perioperatively and controllable complications occurred in 5 cases after operation.All the patients were followed up for 5 to 96 months except for 1 case of benign tumor.None of the benign cases experienced recurrence, and all of them achieved normal hip function.Lung metastases occurred in 10 malignant cases (4 cases of os-teosarcomas and 6 cases of chondrosarcomas) , who died of respiratory failure, and the other 18 remained tumor-free after surgery.Of the 2 patients with malignant fibrohistiocytoma, 1 died 2 years postoperatively and the other survived with tumor.Neither local recur-rence nor lung metastasis was found in the patients with chordoma and malignant chondroblastoma till the end of follow-up.The 5 pa-tients with metastases died within 3 years after operation.At 3 months after surgery, the Harris scores after total hip replacement were >90 in the 7 benign cases, 70-79 in 9 malignant cases, and <70 in the other 19 malignant cases. Conclusion For the treatment of malig-nant tumors, reconstruction by combined pedicle screw fixation system with bone cement does not affect the general daily activities of the pa-tients.Preoperative embolization of the internal iliac artery can reduce bleeding and improve operation safety, and measures should be taken to minimize postoperative complications.

Objective To investigate the effect of selectively upward placement of acetabular implants on limb length and post?operative function of developmental dysplasia of the hip patients with shortened legs during total hip arthroplasty (THA). Methods Twenty?six cases of developmental dysplasia of the hip received THA between January 2008 and December 2013, in?cluding 12 cases of Crowe typeⅠ, 8 of Crowe typeⅡ, 6 of Crowe typeⅢ. There were 5 males and 21 females with an average age of 62.7 years (range, 36-80 years). The left hip was involved in 9 cases and the right hip in 17 cases. The preoperative mean Har?ris score was 42.30±12.84, and the preoperative mean WOMAC score was 59.08±13.84 at the last follow?up. The anteroposterior X?ray films and CT scan of the pelvis, anteroposterior and lateral X?ray films of the femur, and TraumaCad analysis were conducted routinely preoperation. More than 70%of the bone?implant interface was covered by appropriate upward distance of acetabular im?plant. Results The follow?up time ranged from 6 to 73 months (mean, 36 months). The Harris score improved to 91.18±7.09, and WOMAC score reduced to 9.85±3.75. According to postoperative measurement, affected limb had been lengthened by 0-5 mm in 8 cases, 6-10 mm in 5 cases, 11-15 mm in 5 cases,>15 mm in 7 cases, and shortening increased 1 mm in 1 case, but the average lengthening was 9.23±7.54 mm. The upward distance of acetabular implant was 0-5 mm in 10 cases, 6-10 mm in 7 cases and>10 mm in 9 cases. The average lengthening was 6.60±6.72 mm in patients having 0-5 mm upward distance, 11.90±5.64 mm in patients having 6-10 mm upward distance and 10.11 ± 9.35 mm in patients having>15 mm upward distance, showing no significant differ?ence. The leg length discrepancy was-3.70±6.43 mm in patients having 0-5 mm upward distance, 1.71±6.24 mm in patients having 6-10 mm upward distance and 0.56 ± 7.70 mm in patients having>15 mm upward distance, showing no significant difference. Con?clusion The limb length could be improved by selectively upward placement of acetabular implants in developmental dysplasia of the hip patients with anatomically abnormal acetabulum during THA, with reasonable preoperative design and corrective operation.