Low-intensity pulsed ultrasound inhibits IL-6 in subchondral bone of temporomandibular joint osteoarthritis by suppressing the TGF-ß1/Smad3 pathway.

OBJECTIVE: This study aimed to provide further information on the exact mechanisms involved in the anti-inflammatory effect of low-intensity pulsed ultrasound (LIPUS) on rabbit temporomandibular joint osteoarthritis (TMJOA) on interleukin-6 (IL-6) production in subchondral bone, IL-6 production in IL-1ß stimulated via inhibition of the TGF-ß1/Smad3 pathway in mouse embryo osteoblast precursor (MC3T3-E1) cells. DESIGN: Bilateral joints were injected with type II collagenase to establish TMJOA models in two male and four female rabbits. The left joint was continuously stimulated by LIPUS, while the right joint was treated with the power off in this model. One male and two female rabbits were used as normal healthy controls without treatment. The histological features of subchondral bone were examined by Safranin-O/Fast staining. Immunohistochemistry was conducted to evaluate IL-6 expression. Then, cells were stimulated by LIPUS with IL-1ß. IL-6 expression and activity of the TGF-ß1/Smad3 pathway were evaluated by Enzyme-linked immunosorbent assay (ELISA), Immunofluorescence and Western blotting, respectively. Specific inhibition of the TGF-ß1/Smad3 pathway was conducted by transfecting with small interfering RNA (siRNA) of type II receptor (siTßRII). RESULTS: LIPUS significantly ameliorated the production of IL-6 in vitro and in vivo. Its inhibitory effect on the production of IL-6 induced by IL-1ß in MC3T3-E1 cells was partly reversed by siTßRII knockdown. CONCLUSIONS: LIPUS inhibited IL-6 production by suppressing the TGF-ß1/Smad3 pathway of subchondral bone in TMJOA. These data revealed the part of the pathways involved in the anti-inflammatory effect of LIPUS and provided a possible treatment strategy for TMJOA patients and other inflammatory diseases.

Overexpression of HIF-1alpha in Bone Marrow Mesenchymal Stem Cells Promote the Repair of Mandibular Condylar Osteochondral Defect in a Rabbit Model.

PURPOSE: The self-repair ability of temporomandibular joint (TMJ) cartilage is limited. Hypoxia-inducible factor-1 alpha (HIF-1alpha) may induce stem cells to promote chondrogenic repair. The purpose of this study was to systematically evaluate the effect of HIF-1alpha overexpression in bone marrow mesenchymal stem cells (BMSCs) combined with collagen scaffolds on the repair of TMJ condylar osteochondral defects in a rabbit model. METHODS: Osteochondral defects of 3-mm diameter × 2-mm depth were created at the right side of the mandibular condyle in 40 New Zealand white rabbits. The defect sites were treated with simple empty, collagen scaffolds (COL), BMSCs/COL, and HIF-1alpha overexpression BMSCs/COL groups. The histomorphologic features of condylar cartilage were monitored by gross examination, safranin O-fast green staining (Solarbio, Beijing, China), and immunohistochemical staining. The changes in subchondral bone were examined by microcomputed tomography. Immunofluorescence staining was used to trace the transplanted BMSCs in vivo. RESULTS: At 12 weeks postimplantation, histologic staining showed that the osteochondral defects in the simple empty and COL groups were mainly filled with fibrous tissue, whereas the BMSCs/COL and HIF-1alpha overexpression BMSCs/COL groups repaired the defect with fibrocartilage. Furthermore, the cartilage was better organized in the HIF-1alpha overexpression BMSCs/COL group compared with the BMSCs/COL group. Microcomputed tomography showed that osteochondral defects can cause abnormal hyperosteogeny in subchondral bone, and the transplantation of BMSCs, especially HIF-1alpha overexpression BMSCs, may alleviate osteosclerosis. Immunofluorescence staining showed that HIF-1alpha overexpression can promote the survival of transplanted BMSCs. CONCLUSIONS: The transplantation of HIF-1alpha overexpression BMSCs combined with a COL scaffold promotes cartilaginous repair of condylar cartilage and inhibits subchondral bone sclerosis in TMJ condylar osteochondral defect rabbits.

Engineering a Highly Improved Porous Photocatalyst Based on Cu2O by a Synergistic Effect of Cation Doping of Zn and Carbon Layer Coating.

Zn-doped cuprous oxide (Cu2O) nanoparticles coated by carbon layers (Zn/Cu2O@C) have been obtained via a bimetallic MOF (Zn/Cu-MOF-199) as the sacrificial precursor. Originated from the octahedral morphology of Zn/Cu-MOF-199, the as-synthesized Zn/Cu2O@C shows a porous octahedron structure. The obtained Zn/Cu2O@C can afford the following merits. (1) The cation doping of Zn inside Cu2O can enhance the light absorption by introducing impurity energy levels and facilitate the separation of photoinduced electrons and holes. (2) The coating of a carbon layer in Zn/Cu2O@C can also efficiently enhance the separation efficiency of photoinduced charge carriers. (3) The porous structure of Zn/Cu2O@C can provide increased active sites. Therefore, these merits lead to the highly improved photocatalytic activities toward various chemical reactions. In addition, the fully coated carbon layer can facilitate the cycle stability of Zn/Cu2O@C in the photocatalytic processes.

Effective degradation of phenol via catalytic wet peroxide oxidation over N, S, and Fe-tridoped activated carbon.

The N, S, and Fe-tridoped carbon catalysts (NSFe-Cs), Fe/ACNS1 and Fe/ACNS2, were synthesized by wet impregnation with different concentration of ammonium ferrous sulfate solution. The prepared catalysts have a similar textural structure. The N species, S species, FeII and FeIII were simultaneously introduced onto the surface of catalysts. Comparison with the only Fe doped catalyst, NSFe-Cs showed greater stability and higher phenol removal in catalytic wet peroxide oxidation at different reaction condition. The main intermediates including p-hydroxybenzoic acid, formic acid, and maleic acid were determined in the treated wastewater. The high catalytic activity for NSFe-C was related to the ability of H2O2 decomposition. NSFe-Cs have more amount of FeII partially due to the formation of FeS2, which promoted the decomposition of H2O2 on Fe/ACNS1 and Fe/ACNS2 surface. The generation of ·OH and ·HO2/·O2- radicals in the bulk solution was crucial to phenol degradation, and the decomposition of H2O2 complied with the pseudo-first-order kinetics. The highly linear relationship between decomposition kinetic constant for H2O2 and the amount of surface groups suggested, including FeII species, pyridinic N/Fe-bonded N, pyrrolic N as well as graphitic N were responsible to the high activity of NSFe-Cs.

Anterior single-segmental decompression and fixation with a noval rod-screw construct for Denis type B burst fractures / 中华创伤骨科杂志

Objective To evaluate our noval rod-screw construct in anterior single-segmental decompression and fixation for the treatment of Denis type B burst fractures.Methods From February 2007 through May 2010,we treated 28 patients with Denis type B burst fracture.They were aged from 18 to 52 years (average,37.4 years).The fractures were located at T1 1 in 3 cases,at T12 in 10,L1 in 12,and L2 in 3.Of them,7 were complicated with unilateral pedicle fracture and 3 with bilateral pedicle fractures.According to the American Spinal Injury Association (ASIA) scale,the neurological deficits were rated as grade B in 11 cases,as grade C in 9,and grade B in 8.All the patients received anterior single-segmental decompression,titanium mesh and autogenous bone graft,and fixation with our noval rod-screw construct.The therapeutic efficacy was evaluated in terms of visual analogue scale (VAS),cobb angle,and spinal canal encroachment.Results The mean follow-up time was 26 months (range,from 17 to 33 months).The average length of surgery was 144 minutes(range,from 90 to 176 min);the mean blood loss was 580 mL (range,from 300 to 1 100 mL).The mean VAS score,cobb angle and spinal canal encroachment were improved from 8.2 ± 1.5,17.4° ± 4.3° and 53％ ± 16％ preoperatively to 2.7 ± 2.4,9.4° ± 5.8° and 4％ ±2％ at the final follow-up,respectively(P ＜ 0.05).None of the patients exhibited neurological deterioration.Conclusion Our noval rod-screw construct is a safe and effective device that can be used in the anterior single-segmental decompression and fixation for the treatment of Denis type B burst fractures.

Pedicle screw piercer with warning device - A technique to increase accuracy of pedicle screw placement: A cadaveric study.

BACKGROUND: Pedicle screw fixation has achieved significant popularity amongst spinal surgeons for both single and multilevel spinal fusion. Suboptimal placements of pedicle screws may lead to neurological and vascular complications. There have been many advances in techniques available for navigating through the pedicle; however, these techniques are not without drawbacks. The purpose of this study was to investigate the efficacy and feasibility of the pedicle piercer with warning device. MATERIALS AND METHODS: Eight normal adult thoracolumbar specimens from cadavers consisting of 80 vertebras (T8-L5) were selected and randomly allocated into four groups. Each group contained 20 vertebra. Group 1 was tested for maximum pressure of the piercer within the vertebrae (F1). Group 2 was tested for maximum pressure of the warning piercer penetrating front cortex of the vertebral body (F2). Group 3 was tested for the maximum pressure of piercer penetrating vertebral body endplate (F3) and pedicle notch (F41, F42). Group 4 was tested for maximum pressure of the piercer penetrating the vertebral lateral cortex (F6), the medial and lateral cortex of pedicle (F51, F52). In the second experiment of this study, 4 normal adult specimens consisting of 40 vertebra and 80 pedicles were used for testing the alarm effects of pedicle piercer. The following indicators were adopted for the tests including true positive/negative, false positive/negative, sensitivity, specificity, availability, Youden index, and diagnostic efficiency. SPSS 16.0 was used for statistical analysis. RESULTS: There were statistically significant differences between F1, and F2, F3, F41, F42, F51, F52 respectively (P < 0.05). F1 = 8.970 ± 0.2698, F3 = 13.055 ± 0.6718. We found that the threshold value of piercer warning was from 9.6 to 12.3 Kgf. Sensitivity was 92.31%, specificity was 95.12%, usability was 87.45%, Youden index was 87.43% and diagnostic efficiency was 92.5% respectively. CONCLUSION: Warning piercer is a safe, simple, sensitive device for detecting pedicle breach during regular pedicle screw placement surgery.

New anterior plate-rod system for management of thoracolumbar burst fracture / 中华创伤杂志

Objective To evaluate the safety and efficacy of the newly combined anterior platerod system in treatment of acute thoracolumbar burst fracture combined with neurologic deficit.Methods A retrospective study was carried out on 84 consecutive patients with acute thoracolumbar burst fracture combined with neurologic deficits treated by anterior surgery,bone fusion,and internal fixation with the new plate-rod system.There were 61 males and 23 females with a mean age of 31.4 years (range,19-53 years).Primary pathogenesis was high falls in 67 patients,traffic accidents in 13 patients and others in 4 patients.Fractured segments included T11 in 19 patients,T12 in 22,L1 in 25,and L2 in 18.Visual analogue scale (VAS),spinal canal encroachment,and loss of kyphosis correction were measured for all patients to evaluate radiologic and neurological outcomes.Results Bony union occurred in all patients at the 3-5 months of follow-up.There was no pseudarthrosis or vascular complications related to the fixation device.Percentage of canal encroachment decreased from preoperative 70％ to postoperative 2％.Mean segmental kyphotic angle measured 27.9 ° before operation and 7.4 ° after operation,with a mean correction of 20.5°.All patients demonstrated at least one grade of neurological improvement at final follow-up.Mean VAS was improved significantly from preoperative 7.3 points to postoperative 2.9 points.Conclusion The new anterior plate-rod system is safe and effective in treatment of acute thoracolumbar burst fracture combined with neurologic deficit.

Expression of NF-κB, NR2B and iNOS in spinal cord in a rat model of neuropathic pain / 中国病理生理杂志

AIM:To observe the expression of nuclear factor-kappa B ( NF-κB) , N-methyl-D-aspartic acid re-ceptor 2B (NR2B) and inducible nitric oxide synthase (iNOS) in the spinal cord in a rat model of chronic constriction in-jury (CCI) of the sciatic nerve.METHODS:Fifty-six adult male Sprague-Dawley rats weighing 180~220 g were random-ly divided into sham group (n=8) and CCI group (n=48).The mechanical withdrawal threshold (MWT) and paw with-drawal latency (PWL) of the hind paws were measured 1 d before CCI and 1 d, 4 d, 7 d, 14 d and 21 d after surgery.The L4~L6 segment of the spinal cord was taken for determining the expression of NF-κB, NR2B and iNOS by RT-PCR and Western blotting.RESULTS:At 1 d, 4 d, 7 d, 14 d and 21 d after surgery, the MWT and PWL in CCI group were obviously lower than those in sham group .The expression of NF-κB, NR2B and iNOS at mRNA and protein levels in-creased significantly.Positive correlations were found between the mRNA expression of NF-κB and iNOS (r=0.842, P<0.05), and between the mRNA expression of NR2B and iNOS (r=0.833, P<0.05).CONCLUSION:The generation and maintenance of hyperalgesia in sciatic nerve injury rats may attribute to the activation of NF -κB and NR2B and concom-itant increase in iNOS .

Modified technique using allograft-prosthetic composite in the distal femur after bone tumor resection.

BACKGROUND: The purpose of this retrospective study was to analyze the results of treatment of bone tumor resection of the distal femur with the modified technique of allograft-prosthetic composite. METHODS: Twelve patients with distal femoral bone tumors were treated with deep-frozen cortical allograft struts and allograft-prosthesis composites. There were five males and seven females with a median age of 29.5y. The minimum follow-up time was 12mo (median, 45.7mo; range, 12-81mo). Diagnoses included osteosarcoma in five patients, chondrosarcoma in three patients, giant cell tumors in three patients, and malignant fibrous histiocytoma in one patient. Five osteosarcoma patients were treated with adjuvant chemotherapy. RESULTS: At the latest follow-up examination, 11 patients were alive with no evidence of disease, and the limb was preserved in nine patients. One patient died of pulmonary metastases with no evidence of local recurrence. Seven healed without complications. A surgical procedure was performed in four patients because of complications, which included a fracture (one patient), deep infection (one patient), instability (one patient), and local recurrence (one patient). CONCLUSION: The modified technique of allograft-prosthetic composite is an effective treatment for bone tumor resection of the distal femur. This technique has many advantages, including augmentation of the bone stock, minimizing the risk of allograft fracture and nonunion, and decreasing the need for revision operations.

Total en bloc spondylectomy for 9 patients with primary tumor of the lumbar spine / 肿瘤研究与临床

Objective To evaluate the possibility and curative effect of total en bloc spondylectomy (TES) for the treatment of primary tumors of the lumbar spine. MethodsBetween June 2005 and July 2009,nine cases of primary tumor of the lumbar spine were treated with total en bloc spondylectomy through a single posterior approach performed in seven cases(L1 giant cell tumor, L1 osteosarcoma, L2 giant cell tumor,L2 solitary plasmacytoma, L2 chondrosarcoma, L2 chordoma, and L3 histiocytic sarcoma), and two cases through a single stage anterior and posterior combined approach (L4 giant cell tumor with paraspinal mass and L4 fibrosarcoma). They were performed a single stage reconstruction after removing tumors of vertebra. Neurofunction was evaluated perioperatively and recurrence of tumor was tracked for all cases.ResultsThe follow up was obtained for 3-49 months (averaging 19 months). All patients attained significant clinical improvement after surgery without any severe complications. There was no local recurrence and distal metastasis in shortterm follow-up. ConclusionThe treatment by TES to remove tumors and reconstruction of spine are reliable for primary tumors of the lumbar spine. The curative effect of short-term follow-up is satisfactory. However, the long-term curative effect remain to be further follow-up.

Effects of novel β titanium alloy with high strenghth and low elastic modulus on bone healing of osteoporotic fracture in rats / 中华创伤杂志

Objective To investigate the effects of a novel |3 titanium fixation with high strength and low elastic modulus on bone healing of osteoporotic fracture and its effects on stress shielding.Methods Forty female Sprague-Dawley rats were oophorectomized before establishment of femur fracture model.The fracture of left femur was stabilized by titanium alloy pin with high elastic modulus (110 Gpa,high elasticity modulus group) and the fracture of right femur by titanium alloy pin with low elastic modu-lus (30 Gpa, low elasticity modulus group).Six and 12 weeks later, the bone volume (BV) , total vol-ume (TV) and bone volume fraction (BVF) were detected by Micro-CT, and the maximum load was de-tected by biomechanical test.The effects of two titanium alloy pins on formation of bony calluses and me-chanical properties of bones were compared.Results Compared with the low elasticity modulus group, more collagen and bony callus, thicker bone trabeculae and more regular lamellar bone were found in the high elasticity modulus group.In low elasticity modulus group, TV (ROI1) was increased obvious-ly at week 6, with no statistical differences in BV (ROI 1), BV (ROI 2) and maximum load between two groups (P < 0.05).TV and BV in region ROI 1 in the low elasticity modulus group were significantly higher than that in high elasticity modulus group (P < 0.05) , while BV in region ROI 2 in low elasticity modulus group was significantly higher than that in high elasticity modulus group at week 12 postoperative-ly (P<0.05).Biomechnical test indicated that the maximum load in low elasticity modulus group was higher than that in high elasticity modulus group.Conclusions The novel B titanium alloy with high strength and low elastic modulus helps reduce effects of stress shielding, diminish bone resorption, in-crease the fibrous callus formation at the initial phase and improve the quality of bone healing at the later phase.

Effect of low modulus titanium alloy's different surface microtopograph on the biological behavior of rabbits' lacertus fibroblast / 生物医学工程学杂志

This study was undertaken to assess the effect of different surface microtopograph of Ti-Nb-Zr-Sn alloy on the biological behavior and soft tissue integration of rabbits' lacertus fibroblast. The lacertus fibroblasts of Achilles tendon of rabbits were cultured and inoculated on the surface of smooth Ti-flake (control group), and on the surface of sand blast, microgrooves, thread Ti-flakes respectively (3 treatment groups). The cell's growth ratio and attaching status were examined by MTT test and scanning electron microscopy (SEM). The rabbits' lacertus fibroblasts proliferated regularly on the surface of Ti-flakes, and most results of their inter-group comparison showed statistically significant difference (P<0.05), thus indicating the different effects of different surface microtopographs on cell's proliferation; By SEM, the cells were noted to have no obvious directivity on smooth surface; they attached irregularly on the sand blast surface. But in the other two groups, they were oriented regularly along the texture. The cells were almost shuttle-like on the four kinds of surface except for a part of irregular cells on the sand blast surface, and there were plentiful cell-cell junctions. Under high power lens, we found cells with limpid microvilli in the experiment samples. Owing to the cell's fast proliferation and regular attachment in the experiment, we concluded that the regular microgrooved surface was more suitable for meeting the requirement of the soft tissues' physiological function.