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find Keyword "three-dimensional" 147 results
  • EXPERIMENTAL STUDY ON TISSUE ENGINEERED CARTILAGE COMPLEX THREE-DIMENSIONAL NANO-SCAFFOLD WITH COLLAGEN TYPE II AND HYALURONIC ACID IN VITRO

    Objective To explore the possibility of constructing tissue engineered cartilage complex three-dimensional nano-scaffold with collagen type II and hyaluronic acid (HA) by electrospinning. Methods The three-dimensional porous nano-scaffolds were prepared by electrospinning techniques with collagen type II and HA (8 ∶ 1, W ∶ W), which was dissolved in mixed solvent of 3-trifluoroethanol and water (1 ∶ 1, V ∶ V). The morphology were observed by light microscope and scanning electron microscope (SEM). And the porosity, water absorption rate, contact angle, and degradation rate were detected. Chondrocytes were harvested from 1-week-old Japanese white rabbit, which was disgested by 0.25% trypsin 30 minutes and 1% collagenase overlight. The passage 2 chondrocytes were seeded on the nano-scaffold. The cell adhesion and proliferation were evaluated by cell counting kit 8 (CCK-8). The cell-scaffold composites were cultured for 2 weeks in vitro, and the biological morphology and extracelluar matrix (ECM) secretion were observed by histological analysis. Results The optimal electrospinning condition of nano-scaffold was 10% electrospinning solution concentration, 10 cm receiver distance, 5 mL/ h spinning injection speed. The scaffold had uniform diameter and good porosity through the light microscope and SEM. The diameter was 300-600 nm, and the porosity was 89.5% ± 25.0%. The contact angle was (35.6 ± 3.4)°, and the water absorption was 1 120% ± 34% at 24 hours, which indicated excellent hydrophilicity. The degradation rate was 42.24% ± 1.51% at 48 days. CCK-8 results showed that the adhesive rate of cells with scaffold was 169.14% ± 11.26% at 12 hours, and the cell survival rate was 126.03% ± 4.54% at 7 days. The histological and immunohistochemical staining results showed that the chondrocytes could grow well on the scaffold and secreted ECM. And the similar cartilage lacuma structure could be found at 2 weeks after co-culture, which suggested that hyaline cartilage formed. Conclusion The collage type II and HA complex three-dimensional nano-scaffold has good physicochemical properties and excellent biocompatibility, so it can be used as a tissue engineered cartilage scaffold.

    Release date:2016-08-31 04:05 Export PDF Favorites Scan
  • SHORT-TERM EFFECTIVENESS OF SPINAL NAVIGATION WITH INTRA-OPERATIVE THREE-DIMENSIONAL-IMAGING MODALITY IN PEDICLE SCREW FIXATION FOR CONGENITAL SCOLIOSIS

    Objective To investigate short-term effectiveness of spinal navigation with the intra-operative three-dimensional (3D)-imaging modality in pedicle screw fixation for congenital scoliosis (CS). Methods Between July 2010 and December 2011, 26 patients with CS were treated. Of 26 patients, 13 patients underwent pedicle screw fixation using the spinal navigation with the intra-operative 3D-imaging modality (navigation group), while 13 patients underwent the conventional technique with C-arm X-ray machine (control group). There was no significant difference in gender, age, hemivertebra number and location, major curve Cobb angle, and Risser grade between 2 groups (P gt; 0.05). Operation time, operative blood loss, frequency of the screw re-insertion, and postoperative complication were observed. The pedicle screw position was assessed by CT postoperatively with the Richter’s standard and the correction of Cobb angle was assessed by X-ray films. Results All patients underwent the surgery successfully without major neurovascular complication. There was no significant difference in operation time, operative blood loss, and pedicle screw location between 2 groups (P gt; 0.05). A total of 58 screws were inserted in navigation group, and 3 screws (5.2%) were re-inserted. A total of 60 screws were inserted in control group, and 10 screws (16.7%) were re-inserted. There was significant difference in the rate of pedicle screw re-insertion between 2 groups (χ2=3.975, P=0.046). Patients of navigation group were followed up 6-24 months, and 6-23 months in control group. According to Richter’s standard, the results were excellent in 52 screws and good in 6 screws in navigation group; the results were excellent in 51 screws, good in 5 screws, and poor in 4 screws in control group. Significant difference was found in the pedicle screw position between 2 groups (Z= — 1.992, P=0.046). The major curve Cobb angle of 2 groups at 1 week and last follow-up were significantly improved when compared with preoperative value (P lt; 0.05), but there was no significant difference between 1 week and last follow-up (P gt; 0.05). No significant difference in correction rate of the major curve Cobb angle was found between 2 groups at last follow-up (t=0.055, P=0.957). Conclusion Spinal navigation with the intra-operative 3D-imaging modality can improve the accuracy of pedicle screw implantation in patients with CS, and effectually reduce the rate of screw re-insertion, and the short-term effectiveness is satisfactory.

    Release date:2016-08-31 04:06 Export PDF Favorites Scan
  • ANATOMIC STUDY ON HOOK OF HAMATE BONE

    Objective To study the hook of hamate bone by anatomy and iconography methods in order to provide information for the cl inical treatment of injuries to the hook of hamate bone and the deep branch of ulnar nerve. Methods Fifty-two upper l imb specimens of adult corpses contributed voluntarily were collected, including 40 antisepticized old specimens and 12 fresh ones. The hook of hamate bone and its adjacent structure were observed. Twentyfour upper l imbs selected randomly from specimens of corpses and 24 upper l imbs from 12 healthy adults were investigated by computed tomography (CT) three-dimensional reconstruction, and then related data were measured. The measurement results of24 specimens were analyzed statistically. Results The hook of hamate bone is an important component of ulnar carpal canal and carpal canal, and the deep branch of ulnar nerve is located closely in the inner front of the hook of hamate bone. The flexor tendons of the forth and the l ittle fingers are in the innermost side, closely l ie next to the outside of the hook of hamate bone. The hamate bone located between the capitate bone and the three-cornered bone with wedge-shaped. The medial-, lateral-, and front-sides are all facies articularis. The hook of hamate bone has an approximate shape of a flat plate. The position migrated from the body of the hamate bone, the middle of the hook and the enlargement of the top of the hook were given the names of “the basis of the hook”, “the waist of the hook”, and “the coronal of the hook”, respectively. The short path of the basement are all longer than the short path of the waist. The long path of the top of the hook is the maximum length diameter of the hook of hamate bone, and is longer than the long path of the basement and the long path of the waist. The iconography shape and trait of the hook of hamate bone is similar to the anatomy result. There were no statistically significant differences (P gt; 0.05) between two methods in the seven parameters as follows: the long path of the basement of the hook, the short path of the basement of the hook, the long path of the waist of thehook, the short path of the waist of the hook, the long path of the top of the hook, the height of the hook, of hamate bone, and the distance between the top and the waist of the hook. Conclusion The hook of hamate bone can be divided into three parts: the coronal part, the waist part, and the basal part; fracture of the hamate bone can be divided into fracture of the body, fracture of the hook, and fracture of the body and the hook. Facture of the hook of hamate bone or fracture unnion can easily result in injure of the deep branch of ulnar nerve and the flexor tendons of the forth and the l ittle fingers. The measurement results of CT threedimensional reconstruction can be used as reference value directly in cl inical treatments.

    Release date:2016-08-31 05:47 Export PDF Favorites Scan
  • COMBINED APPLICATION OF GREEN FLUORESCENT PROTEIN LABELING AND CONFOCAL LASER SCANNING MICROSCOPE THREE-DIMENSIONAL RECONSTRUCTION TO MONITOR CONSTRUCTION AND IN VIVO TRANSPLANTATION OF TISSUE ENGINEERED BONE

    Objective The combined appl ication of green fluorescent protein (GFP) and confocal laser scanning microscope three-dimensional reconstruction (CLSM-3DR) were used to monitor the construction and in vivo transplantation of tissue engineered bone (TEB), to provide for technology in selection of scaffolds and three-dimensional constructional methods. Methods After bone marrow mesenchymal stem cells (BMSCs) were isolated from a 2-year-old green goat by a combination method of density gradient centrifugation and adherent culture, and the expressions of CD29, CD60L, CD45, and CD44 in BMSCs were detected by flow cytometry. Plasmid of pLEGFP-N1 was ampl ified, digested by enzymes (Hind III, BamH I, Sal I, and Bgl II), and identified. Transfection of pLEGFP-N1 into PT67 cells was performed under the help of l iposome. Positive PT67 cells were picked out with G418, and prol iferated for harvesting virus. Based on the titre of virus, after BMSCs were infected by virus containing pLEGFP-N1, GFP positive BMSCs were collected and prol iferated for seeding cells. TEB was fabricated by GFP positive BMSCs and decalcified bone matrix (DBM) and observed by CLSM-3DR for the evaluation of the distribution and prol iferation of seeding cells. After TEB was transplanted in the defect of goat femur, CLSM was used for observing the survival and distribution of GFP positive cells in the grafts. Results The isolated cells were fibroblast-l ike morphous, with the positive expression of CD29 and CD44, and negative expression of CD60L and CD45. The digested production of pLEGFP-N1 was collected for ionophoresis, whose results showed the correct fragment length (6 900 bp). The virus of pLEGFP-N1 was harvested by transfection of pLEGFP-N1 into PT67 cells and used for further infection to obtain GFP positive BMSCs. The prol iferated GFP positive BMSCs and DBM were used for fabrication of TEB. The distribution, prol iferation, and migration of BMSCs in TEB were observed by CLSM-3DR. GFP positive cells also were observed in images of TEB graft in goat femur 28 days after transplantation. Conclusion The BMSCs labeled by GFP in three-dimensional scaffold in vivo were monitored well by CLSM-3DR. It suggests a wide use potency in monitoring of three-dimensional cultured TEB.

    Release date:2016-08-31 05:48 Export PDF Favorites Scan
  • Three-dimensional computed tomography reconstruction of the eyes before and after removing the scleral encircling buckles

      Objective To measure the changes of eye shape and axial length of the eyeball before and after removing the scleral encircling buckles.Methods This is a prospective and controlled study. Twenty eyes (20 patients) with rhegmatogenous retinal detachment and the fellow eyes were enrolled in this study. All patients underwent scleral encircling buckling, and the buckles were removed 2.0-3.5 years after the surgery. The eye shape and axial length of both eyes were measured by three-dimensional computed tomography (3D-CT) before and one,three,six months after the removing surgery. The axial length was also measured by intraocular lens (IOL) Master.Results 3D-CT showed that buckled eyeball depressed at the equator, resulting in a gourd-shaped eyeball. One month after removing the encircling buckle the depression disappeared. By 3D-CT scanning, the axial lengths of buckled eyes were (27.65plusmn;1.22), (27.3plusmn;1.56), (27.29plusmn;1.46) and (27.12plusmn;1.49) mm before and one, three, six months after the removing surgery respectively. The difference between before and after removing surgery was not statistically significant (t=2.89,P=0.723). By IOLMaster, the axial length of operated eyes were (28.32plusmn;1.94), (28.17plusmn;1.87), (28.21plusmn;1.94), (28.25plusmn;1.93) mm respectively. The difference between before and after removing the encircling band was not statistically significant (t=3.304, P=0.93). There was no significant difference in these two measuring modes (t=3.705,P=0.847).Conclusions Encircling buckling can cause eyeball indentation, removing the encircling band can rescue the indentation. There are no changes in the axial length before and after removing the encircling buckles.

    Release date:2016-09-02 05:41 Export PDF Favorites Scan
  • Features of computer-assistant three-dimensional ultrasound diagnosis in ocular fundus diseases

    Objective To detect the value of three-dimensional (3D) ultrasound diagnosis in common ocular fundus diseases. Methods Two-dimensional (2D) images of 38 patients with common ocular fundus diseases were three-dimensionally reconstructed via 3D ultrasound workstation. The 3D images reflecting the ocular diseases were analyzed. Result In 38 patients with common ocular fundus diseases, there was vitreous hemorrhage in 16 patients, retinal detachment in 12, choroidal detachment in 5, and intraocular space occupying lesion in 5. Compared with the 2D images, 3D reconstructed images reflect the lesions more intuitionistically, displayed the relationship between the lesions and the peripheral tissues more clearly, and revealed the blood flow more specifically. During a scanning examination, 3D reconstructed technology provided the diagnostic information of section of X, Y and Z axises simultaneously which shortened the time of examination; the condition of any point of lesions and the relation between the lesion and the peripheral tissues could be gotten by the tools like cut and chop provided by 3D imaging software itself, which avoided detecting the same lesion with different angles and lays and proved the diagnostic efficacy. Conclusions 3D ultrasound diagnosis is better than 2D in diagnosis of vitreous, retina, choroid, and intraocular space occupying lesion. 3D ultrasound diagnosis is a complementarity for the 2D one, and the Z axis changes the former observational angles which may provide the new way of precise diagnosis. (Chin J Ocul Fundus Dis, 2005, 21: 381-383)

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
  • Application of an R-group Search Strategy into Three-dimensional Quantitative Structure-activity Relationship of HEA β-secretase Inhibitors and Molecular Virtual Screening

    The β-secretase is one of prospective targets against Alzheimer's disease (AD). A three-dimensional quantitative structure-activity relationship (3D-QSAR) model of Hydroethylamines (HEAs) as β-secretase inhibitors was established using Topomer CoMFA. The multiple correlation coefficient of fitting, cross validation and external validation were r2=0.928, qloo2=0.605 and rpred2=0.626, respectively. The 3D-QSAR model was used to search R groups from ZINC database as the source of structural fragments. As a result, a series of R groups with relatively high activity contribution was obtained to design a total of 15 new compounds, with higher activity than that of the template molecule. The molecular docking was employed to study the interaction mode between the new compounds as ligands and β-secretase as receptors, displaying that hydrogen bond and hydrophobicity played important roles in the binding affinity between the new compounds and β-secretase. The results showed that Topomer CoMFA and Topomer Search could be effectively used to screen and design new molecules of HEAs as β-secretase inhibitors, and the designed compounds could provide new candidates for drug design targeting AD.

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  • Assessment of Left Ventricular Global Systolic Function Using Real-time Three-dimensional Speckle-tracking Echocardiography in Patients with Hypothyroidism

    The present study aimed to investigate the impact of hypothyroidism on left ventricular systolic function using real-time three-dimensional speckle tracking imaging (RT3D-STI). Thirty hypothyroidism patients and forty healthy volunteers were recruited and received RT3D-STI measurement of global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and global area strain (GAS). A comparison of differences between the hypothyroidism patients and those in the healthy group was carried out and we obtained the results as followings. The values of GLS were (-18.93°3.89) vs. (-21.44°1.99), with P<0.01, GRS were (51.13°11.95) vs. (56.10°5.76), with P<0.0; and GAS were (-31.63°5.38) vs. (-34.40°2.32), with P<0.01, i.e. they were lower in hypothyroidism group than those in the health group. While GCS were (-17.75°1.92) vs. (-17.03°3.45), with P>0.05, which were not significantly different between the two groups. In linear regression, GLS showed significant correlation with both TSH (b=-0.69, P<0.01) and FT3(b=0.71, P<0.01). Meanwhile, the GRS (b=2.98, P<0.05) and GAS (b=3.11, P<0.05) linearly correlated with FT3 level. In conclusion, the present study shows that the global longitudinal and radial moves of left ventricular are weaker in patients with hypothyroidism than healthy controls. And the impairment of left ventricular function would aggravate as FSH rises or FT3 declines.

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  • Investigation on Biomechanics Behavior Using Three-dimensional Finite Element Analysis for Femur Shaft Fracture Treated with Locking Compression Plate

    Based on the CT data and the structure characteristics of the femoral fractures during different healing stages, medical FE models of fractured femur treated with locking compression plate (LCP)were built.Under the physiological load of a standard body weight (70 kg) and the constraint condition,the stress distributions of LCP and fractured femur during healing were calculated by means of three-dimensional finite element analysis (3D-FEA).The results showed that the stress distribution in the LCP and the fractured femur was similar,during the initial stage which there was no newly formed bone or soft tissue in fracture site.The maximum von Mises stress (371.23,272.76 MPa) in the fractured femur was much higher than that in natural femur,and the intensive stress was concentrated mainly in the proximal area of the fractured femur.With the growth of bony callus bone in fracture site,the intensity of stress in proximal femur decreased.Contrasted to the two cases mentioned above,the value of the maximum von Mises stress (68.17 MPa) in bony callus bone stage decreased significantly,and was lower than the safe strength of natural bone.Therefore,appropriate training which is benefitial for the growth to new bone could be arranged for the better rehabilitation.

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  • A Probability Segmentation Algorithm for Lung Nodules Based on Three-dimensional Features

    This paper presents a probability segmentation algorithm for lung nodules based on three-dimensional features. Firstly, we computed intensity and texture features in region of interest (ROI) pixel by pixel to get their feature vector, and then classified all the pixels based on their feature vector. At last, we carried region growing on the classified result, and got the final segmentation result. Using the public Lung Imaging Database Consortium (LIDC) lung nodule datasets, we verified the performance of proposed method by comparing the probability map within LIDC datasets, which was drawn by four radiology doctors separately. The experimental results showed that the segmentation algorithm using three-dimensional intensity and texture features would be effective.

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