ObjectiveTo explore the mechanical stability of the three-dimensional (3-D) external fixator for osteoporotic fracture so as to provide the biomechanical basis for clinical application. MethodsForty-five fresh frozen adult tibial specimens were selected to rapidly prepare the extracorporal tibia osteoporotic fracture models, and were randomly divided into 3 groups (n=15). Fractures were fixed with 3-D external fixators (3-D external fixators group), intramedullary nails (intramedullary nail group), and plate (plate group) respectively. Five specimens randomly from each group were used to do axial compression test, three-point bending test, and torsion test with microcomputer control electronic universal testing machine, then the mechanical parameters were calculated. ResultsIn the axial compression test, the displacement of 3-D external fixator group and intramedullary nail group were shorter than plate group, showing significant differences (P<0.05); but no significant difference was found between 3-D external fixator group and intramedullary nail group (P>0.05). In the three-point bending test and torsion test, the deflection and the torsional angle of 3-D external fixator group and intramedullary nail group were smaller than plate group, showing significant differences (P<0.05); but no significant difference was found between 3-D external fixator group and intramedullary nail group (P>0.05). ConclusionThe 3-D external fixator can fix fracture three-dimensionally from multiple plane and it can offer strong fixing. It is biomechanically demonstrated to be suitable for osteoporotic fracture.
ObjectiveTo observe the effects of A549 cells under hypoxicconditions on the migration of human umbilical vein endothelial cells (HUVECs) and microvascular formation. MethodsAfter cultured for 24 h in normoxia condition(21% O2),hypoxia condition (2% O2),and anaerobic condition (0% O2),respectively,morphology of A549 cells was observed with inverted phase contrast microscope,proliferation was detected by MTT assay,and intracellular hypoxia-inducible factor-1α (HIF-1α) protein was detected by immunocyto-chemical technique,for determining whether the hypoxia model is successful. Then A549 cells' supernatant in the normoxic group,the hypoxia group and HUVECs culture medium were taken to intervene HUVECs. The migration of HUVECs was observed with cell scratch test,pseudopodia formation of HUVECs was observed with microfilament green fluorescent staining method,and blood vessel formation was observed with three-dimensional culture techniques in vitro. ResultsCompared with the normoxic group,the growth of A549 cells was better in the hypoxia group with more proliferation,and was poor in the anaerobic group with decreased number of cells. A549 cells in the hypoxia group and the anaerobic group both expressed HIF-1α protein,which was more obvious in the anaerobic group. Compared with the HUVECs supernatant intervention group,the hypoxia supernatant intervention group and the normoxic supernatant intervention group both had varying degrees of migration,pseudopodia structure formation and vascular lumen sample structure formation,which were more obvious in the former group. ConclusionA549 cells in hypoxic environment grow very well,proliferated significantly,but anaerobic environment is not conducive to the growth of A549 cells which found to be apoptosis. A549 cells in hypoxic environment can promote HUVECs migration,pseudopodia formation and angiogenesis.
Objective To study the clinical significance of multi-slice spiral CT in portal vein imaging. Methods One hundred and thirty seven cases underwent enhanced scan with GE Light SpeedQX/i4 CT scanner were collected, including 41 cases of liver cancer, 20 cases of hepatic cirrhosis, 21 cases of cavernous hemangioma of liver, 9 cases of hepatic abscess, 6 cases of carcinoma of gallbladder, 14 cases of cholangiocarcinoma, 16 cases of pancreatic carcinoma, and 5 cases in normal. The results of portal vein images were reconstructed with three-dimensional software and analyzed. Results In 109 cases, portal vein, cranial mesenteric vein, and splenic vein were demonstrated successfully in the stage of portal vein: volume rendering images were clear in 84 cases, and maximum intensity projection images and multiplanar reconstruction images were clear in 109 cases. Forty-five cases of portal hypertension, 18 cases of opened collateral circulation, 15 cases of portal vein tumor thrombus, 1 case of splenic vein tumor thrombus, and 6 cases of large cavernous hemangioma were demonstrated successfully. Conclusion The portal vein imaging with multi-slice spiral CT can show the dissection and lesions of portal vein and its branches clearly, and can provide the clinical evidence for clinicians to formulate a treatment plan correctly.
ObjectiveTo investigate the growth characteristics of pancreatic cancer cells in the twodimensional culture system (monolayer) and threedimensional culture system (type Ⅰ collagen and extracellular matrix gel). MethodsThree pancreatic cancer cell lines (SW1990, PCT, and ASPC1) were cultured in monolayer, type Ⅰ collagen, and extracellular matrix gel, respectively. The growth patterns were observed, growth curves were detected by CCK8 test, and the cell cycle distributions were analyzed by propidium iodide staining. Results In the twodimensional culture system, cells grew in monolayer. In the type Ⅰ collagen and the ECM gel threedimensional culture system, cells formed multicellular spheroids (MCS), of which the growth rates were slower than those of the cells in monolayer. The proportions of S phase of SW1990, PCT, and ASPC1 cells in twodimensional culture system were significantly more than those in the type Ⅰ collagen on 4 d and 8 d 〔(29.6±3.0)% vs. (18.2±5.1)%, (33.6±2.1)% vs. (14.5±3.2)%, (33.1±1.8)% vs. (24.7±2.6)%; Plt;0.05〕, while the difference of proportion of three cell lines in G2/M phase was not different between twodimensional culture system and type Ⅰ collagen (Pgt;0.05). The proportions of G0/G1 phase of SW1990 and PCT cells cultured in the type Ⅰ collagen on 4 d and 8 d and ASPC1 cells cultured in the type Ⅰ collagen on 4 d were significant more than those cultured in twodimensional culture system (Plt;0.05). The proportions of S phase of ASPC1 cells and SW1990 cells cultured in the type Ⅰ collagen on 4 d were significant more than those cultured in the type Ⅰ collagen on 8 d (Plt;0.05). ConclusionsThe characteristics of pancreatic cancer cells in twodimensional and threedimensional culture systems are different. MCS culture system can better mimic the in vivo growth environment of cells in tumors.
Objective To develop hepatic surgical planning software for hepatic operation on deciding the rational operational scheme and simulating procedures before the operation to accomplish the precise liver resection and decrease the operational risk. Methods3D-econstruction of liver was restored from spiral computed tomography (CT) data by using LiVirtue software. The liver and its anatomic structures were reconstructed to illuminate the location of the tumor and its related vessels to design a rational operational scheme. The virtul results, such as liver volume, hepatic sections, anatomy of portal vein and hepatic veins or possible operation plans, were compared with the actual situations during the operations. Results3D models of liver, tumor and their relative vessels were reconstructed successfully. Preoperative planning and intra-perative navigation based on the models ensured the safety of liver resection in our 32 cases of right lobe tumors. This preoperative simulation allowed surgeons to dissect the liver with reduced complications. These models could be also viewed and manipulated on personal computers.ConclusionThe LiVirtue is very helpful in the hepatic surgery, for clearly disclosing hepatic structures, rationally deciding operation schemes, virtually simulating the operations. This preoperative estimation from 3D model of liver benefits a lot to complicated liver resection.
Objective To evaluate the application value of spiral CT virtual endoscopy and three dimensional imaging in fiberoptic bronchoscopic balloon dilation in patients with benign tracheobronchial stenosis. Methods Thirty-three cases of benign tracheobronchial stenosis from June 2004 to November 2008 were checked by spiral CT with airway tracheobronchial reconstruction. For the patients with indications, balloon dilatation was performed under fiberoptic bronchoscope. The three-dimensional reconstruction images were compared with the findings under bronchoscopy. And the preoperative and postoperative three-dimensional reconstruction images were compared for airway diameter. Results Three cases were found stenosis of middle lobe by CT virtual endoscopy and did not undergo balloon dilatation. The remaining 30 cases were confirmed by bronchoscopy findings similar to the images by tracheobronchial reconstruction with CT, with consistent rate of 100% . Immediate postoperative three-dimensional CTreconstruction of tracheal bronchus revealed that diameter of stenotic bronchus increased from ( 2. 7 ±1. 3) mm to ( 6. 9 ±1. 6) mmafter operation. Conclusion Multislice spiral CT virtual endoscopy is helpful in fiberoptic bronchoscopic balloon dilation in patients with benign tracheobronchial stenosis and postoperative follow-up.
Objective To review recent advance in the application and research of three-dimensional digital knee model. Methods The recent original articles about three-dimensional digital knee model were extensively reviewed and analyzed. Results The digital three-dimensional knee model can simulate the knee complex anatomical structure very well. Based on this, there are some developments of new software and techniques, and good clinical results are achieved. Conclusion With the development of computer techniques and software, the knee repair and reconstruction procedure has been improved, the operation will be more simple and its accuracy will be further improved.
Objective To investigate the effects of in-vitro monolayer culture and three-dimensional (3-D) alginate microsphere culture on the differentiation of normal human nucleus pulposus cells (NPCs), and to discuss the regulatory mechanism of restoring the phenotype of dedifferentiated NPCs by culturing resveratrol (RES) in 3-D alginate microsphere. Methods Normal human nucleus pulposus tissues were harvested for culture and identification of NPCs from 6 patients with burst lumbar vertebra fracture. NPCs at passages 1, 3, 5, and 7 in the in-vitro monolayer culture were harvested to observe the morphology, cell aging, and proteoglycan expression. The cell proliferation rates of NPCs at passage 1 in-vitro in monolayer culture and in 3-D alginate microsphere culture were detected. NPCs at passage 7 were randomly divided into 3-D alginate microsphere control group (group A), RES group (group B), silent mating type information regulation 2 homolog 1 (SIRT1)- small interfering RNA (siRNA) + RES group (group C), and negative control-siRNA + RES group (group D); and NPCs in the in-vitro monolayer culture was monolayer control group (group E). After corresponding treatment, Western blot was used for determining the protein expressions of SIRT1, Aggrecan, and collagen type II; real-time fluorescence quantitative PCR was used for detecting SIRT1 mRNA expression. Results The cultured cells were identified to be NPCs. Morphological observation, senescence-associated β-galactosidase (SA-β-gal) staining, and toluidine blue staining showed that dedifferentiation of normal NPCs tended to occur under continuous in-vitro monolayer culture, which was more obvious with increase of passage number. NPCs in 3-D alginate microsphere culture showed significantly lower proliferation rate than NPCs in the in-vitro monolayer culture (P lt; 0.05), but it could significantly improve the protein expressions of collagen type II and Aggrecan in dedifferentiated NPCs, showing significantly difference between groups E and A (P lt; 0.05). The protein expressions of SIRT1, collagen type II, and Aggrecan in group B were significantly improved when compared with that in group A (P lt; 0.05). Real-time fluorescence quantitative PCR and Western blot showed that the expressions of SIRT1 mRNA and proteins in group C were significantly inhibited after transfected with SIRT1-siRNA when compared with those in groups B and D (P lt; 0.05), and the protein expressions of collagen type II and Aggrecan in group C were significantly lower than those in groups B and D (P lt; 0.05). Conclusion Continuous in-vitro monolayer culture could efficiently cultivate numerous seeding NPCs, but it is liable to dedifferentiate. In 3-D alginate microsphere culture, RES could restore the phenotype of dedifferentiated NPCs and synthesize more extracellular matrix, which is related to the regulation of SIRT1.
Objective To investigate the feasibility of establishing the visualization models of intraneural microvessels of sciatic nerves in Sprague Dawley (SD) rats by systemic infusion of Evan’s blue (EB) or lead oxide and to compare the advantages and disadvantages. Methods Fifteen healthy adult SD rats of either gender, weighing 200-250 g, were randomly divided into traditional group (group A, n=5), fluorescence group (group B, n=5), and radiography group (group C, n=5). Ink, EB, and lead oxide, all mixed with gelatin solution, were injected in groups A, B, and C, respectively. After 2 hours of cryopreservation under 4°C, all sciatic nerves were harvested and observed through stereomicroscope to make sure the filling condition. The two-dimentional (2D) images were then collected via reflexion fluorescent microscope in group B and via micro-CT scan in group C. All images were imported into computer to establish three-dimentional (3D) reconstruction models by Mimics 15.0. Results All groups could show the outline of intraneural microvessels of sciatic nerves under stereomicroscope. Diameters of them were measured under fluorescent microscope, ranging from 10 µm to 30 µm. Both groups B and C could establish 3D reconstruction models from 2D images. These models could clearly reproduce the structure of microvessels. Conclusion Both EB and lead oxide can be used to establish 3D reconstruction models to observe structure of the intraneural vessels. However, EB has some disadvantages, such as predisposition to infiltration, grainy 2D images and time-consuming procedure; it is not suitable for researches of large specimen. Though 2D pictures from lead oxide have lower resolution than EB, it is easier to be manipulated and appropriate for experiments of large specimen.
Objective To evaluate the directional significance of SurgiCase software in free fibula mandibular reconstruction. Methods Between September 2010 and March 2012, 10 patients with mandibular defect underwent free fibula mandibular reconstruction. There were 7 males and 3 females, with an age range of 19-43 years (mean, 27 years). The extent of lesions was 7 cm × 5 cm to 16 cm × 8 cm. In each case, three-dimensional spiral CT scan of the maxilla, mandible, and fibula was obtained before surgery. The CT data were imported into the SurgiCase software and the virtual surgery planning was performed. After that, the mandibular rapid prototyping was made according to customized design. The reconstruction surgery was then carried out using these preoperative data. During actual surgery, the extent of mandibular defect was from 6 cm × 3 cm to 16 cm × 5 cm; the length of fibula which was used to reconstruct mandible was 6-17 cm; and the area of flap was from 6 cm × 5 cm to 16 cm × 6 cm. Results Preoperative data could not be applied because the intraoperative size of tumor was larger than preoperative design in 1 case of mandibular ameloblastoma, and the fibula was shaped according to the actual osteotomy location; operations were performed successfully according to preoperative design in the other 9 patients. The operation time was 5-7 hours (mean, 6 hours). Primary healing of incision was obtained, without early complications. Ten patients were followed up 1 year. At last follow-up, 8 patients were satisfactory with the appearance and 2 patients complained with unsatisfied wide facial pattern. The panoramic radiograghs showed good bone healing. The range of mouth opening was 2.5-3.5 cm. Conclusion SurgiCase software can provide precise data for free fibula mandibular reconstruction during surgery. It can be applied widely in clinic.