Pre-clinical application of self-developed computer assisted design/rapid prototyping and guidance system to assist precise acetabular component placement: A pilot study / 中华创伤骨科杂志

Objective To introduce a self-developed computer-assisted design/rapid prototyping and guidance system used for precise placement of the acetabular component in total hip arthroplasty.Methods We collected the preoperative pelvic CT scanning data of 10 hips with aeetabular dysplasia that had undergone primary total hip arthroplasty from January 2016 to January 2017.The total time for import of radiographic images,model reconstruction,model segmentation,acetabular component position design and STL model export was calculated and compared between our self-designed software and Mimics vl 7.0.Three kinds of STL model from each case were imported into our self-developed 3D printing device,Stratasys Objet30 and Stratasys Demension SST1200es respectively for rapid prototyping.The printing efficiency and accuracy were compared among the 3 printers.The accuracy of placing acetabular component with guidance system was evaluated.Results The average time forpreoperative planningwas7.7±1.3 minbyourself-designedsoftware and 52.5 ± 15.9 min by Mimics v17.0,showing a significant difference (P ＜ 0.001).In morphological point-based comparison for each case,the 3D models exported by the 2 different kinds of software showed an average difference of 0.072 1 ± 0.069 1 mm.The average durations for rapid prototyping by the 3 different printers were 5.3 ± 0.6 h,10.8 ± 0.5 h,and 9.3 ± 0.6 h,respectively,showing significant differences (P ＜ 0.001).The guidance system resulted in precise placement.The locations of the acetabular component achieved by guide-assisted placement were not significantly different from the target ones (P ＞ 0.05).Conelusion Our self-developed preoperative planning software,rapid prototyping device and guidance apparatus for acetabular component placement may lead to good accuracy and high efficiency.

Resisin stimulates the expression of CCL3 and CCL4 in chondrocytes / 中国组织工程研究

BACKGROUND:Previous studies have indicated that resistin stimulates a large set of chemokines in chondrocytes that are known to be important in inflammatory joint lesions. OBJECTIVE:To further investigate the mechanism of co-regulation roles of transcription and post-transcription in the up-regulation of two chemokine genes CCL3 and CCL4 in chondrocytes in response to resistin. METHODS:Human chondrocytes, T/C-28a2 and ATDC5 cels were cultured. The function of resistin on the chemokine genes, and the expression of C/EBPβ, nuclear factor-κB isoforms and chondrogenic specific miRNAs were tested by qPCR. The co-regulation of C/EBPβ and nuclear factor-κB was investigated by nuclear factor-κB inhibitor (IKK-NBD) and C/EBPβ inhibitor (SB303580) treatments, and subcelular localization was detected with or without resistin stimulation. RESULTS AND CONCLUSION:Resistin could increase the expression of chemokine genes independently. Chondrocytes reacted in a non-restrictedly cel-specific manner to resistin; C/EBPβ inhibitor, nuclear factor-κB and some chondrogenic specific miRNAs in a combinatorial manner regulated chemokine gene expression. The activity of C/EBPβ was augmented by a transient increase in activity of nuclear factor-κB, and both transcription factors acted independently on the chemokine genes, CCL3 and CCL4.

The effect of selectively upward placement of acetabular implants on limb length and post-operative function of develop-mental dysplasia of the hip patients with shortened legs / 中华骨科杂志

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.

Gait parameters in lower extremities of patients in sequela period after unilateral total hip arthroplasty / 中国组织工程研究

BACKGROUND:Total hip arthroplasty is known to be a successful surgical procedure to al eviate hip pain and to regain gait ability, but there are many debates on whether patients’ gait could reach a normal level several years later. OBJECTIVE:To investigate spatiotemporal parameter characters of lower extremities in patients during walking in sequela period fol owing unilateral total hip arthroplasty, and to probe into patients’ walking abilities. METHODS:In accordance with the method of Case Database Data Analysis detected by Motion Reconstruction Laboratory, 14 patients at 5-10 years after total hip arthroplasty served as the experimental group, and 14 matched healthy persons served as the control group. Gait parameters of lower extremities during walking were col ected by Vicon Nexus. Spatiotemporal parameter characters of lower extremities during gait cycle were analyzed by using Polygon. RESULTS AND CONCLUSION:Compared with the control group, walking speed, cadence, stride length and step length decreased, but double support and opposite foot off increased on both affected and unaffected sides in the experimental group (P0.05). The results suggested that gaits of patients showed good gait symmetry at 5-10 years after surgery. However, they do not reach the level that observed in healthy subjects, and walking ability was poorer than normal persons. Systematic rehabilitation training is needed to improve walking ability.

Cartilage surface of early osteoarthritis in rats induced by papain under scanning electron microscope / 中国组织工程研究

BACKGROUND:Osteoarthritis animal models induced by papain are commonly used for studying osteoarthritis. OBJECTIVE:To observe the morphology of articular cartilage surface during early osteoarthritis process in rats induced by papain and L-cysteine under scanning electron microscope. METHODS:The right knees of Sprague-Dawley rats were given 0.15 mL mixed solution of 2%papain and 0.03 mol/L L-cysteine in the ratio of 2:1. The left knees were given injections of 0.15 mL 0.9%NaCl, as the control group. Another two rats (four knees) maintained untreated, as the normal control group. Al the rats were observed with scanning electron microscope at 2, 4, 6 weeks after injection, to explore the surface morphology of medial condyle of femur. RESULTS AND CONCLUSION:The condyles of normal and control groups revealed numerous shal ow pits on the surface of articular cartilage. At 2 weeks after injection, the surfaces of condyles were unsmooth, presenting the shrinkage and distortion. The thinner articular cartilage and local tiny cracks were seen at 4 weeks. The deep and great cracks and cartilage defect were observed on the surface of cartilage at 6 weeks. The time of 4-6 weeks is a reference point for establishing early osteoarthritis model in rats through injections of 2%papain and 0.03 mol/L L-cysteine.

Mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation: observations by intravascular ultrasound / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation.</p><p><b>METHODS</b>Twenty-eight patients undergoing provisional T technique were enrolled in this study. Intravascular ultrasound (IVUS) examination was performed before and after main vessel stenting and kissing balloon post-dilatation to evaluate the geometrical changes of the vessels.</p><p><b>RESULTS</b>The CSA of LCX ostium lumen decreased significantly from 5.9∓2 mm(2) to 4.9∓1.9 mm(2) (P<0.01) after the procedure, and the CSA of LCX ostium P and M increased from 5.4∓2.9 mmmm(2) to 5.7∓2.9 mm(2) (P=0.21) after the main vessel stenting. The changes in LCX ostium lumen CSA was correlated with the changes of LCX ostium EEM CSA but not the LCX ostium P and M CSA. After kissing balloon post-dilatation, the CSA of LCX ostium lumen increased from 4.9∓1.9 mm(2) to 5.5∓1.9 mm(2) (P<0.01) , and the CSA of LCX ostium P and M showed no obvious changes (5.7∓2.9 mmmm(2) vs 5.7∓2.6 mmmm(2), P=0.89). The changes of LCX ostium lumen CSA were correlated with the those of the LCX ostium EEM CSA (R=0.432, P=0.02).</p><p><b>CONCLUSION</b>After stent implantation from the LMCA to the LAD, most of lumen losses of the LCX are due to carina shift, and in occasional cases, plaque shift occurs from the distal LMCA to the ostium of the LCX. Kissing balloon technique can adjust carina shift but can not improve plaque shift.</p>

Inhibitory effect of interleukin-1 receptor-associated kinase-4 silencing on mitogen-activated protein kinases expression in human osteoblast-like cells / 中国组织工程研究

BACKGROUND:The molecular mechanism of periprosthesis osteolysis is not yet completely clear. Periprosthetic osteolysis and absorption is the pathological and physiological process typical of artificial joint loosening. Interleukin-1 can affect bone resorption process through a mitogen-activated protein kinases (MAPK) signaling pathway. OBJECTIVE:To explore the effects of siRNA-induced interleukin-1 receptor-associated kinase-4 gene (IRAK-4) silence on MAPK expression in MG63 cells, which may provide experimental basis for treatment and prevention of periprosthesis osteolysis. METHODS:The siRNA sequences of the target gene, IRAK-4, were constructed and transferred into MG63 cells using Lipofectamine 2000. There were three groups:blank group=MG63 cells, control group=MG63 cells transfected with scrambled IRAK-4siRNA, and silence group=MG63 cells transfected with specific IRAK-4 siRNA. The protein level of extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (p38MAPK) were detected by western blot assay. RESULTS AND CONCLUSION:The expression of IRAK-4 mRNA and protein in the silence group was significantly decreased compared with the control group. Compared with the blank and control groups, 48 hours after the transfection, IRAK-4 gene silencing in MG63 cells decreased protein expression of p-JNK1/2P46, p-ERK1/2 and p-p38MAPK (P<0.05). IRAK-4 silencing inhibited ERK, JNK and p38MAPK expression in osteoblast-like cells.

A novel biomechanical testing protocol for osteoporosis in rats: femur metaphysis bending test / 中华骨科杂志

ObjectiveTo establish a new biomechanical test for evaluating biomechanical properties of femoral metaphysis in ovariectomized rats.MethodsTwenty-five-month-old female Sprague-Dawley rats were randomly divided into ovariectomized (OVX) group and the sham-operated (Sham) group (n=10).Twelve weeks after operation,femur BMD and histomorphometry of distal femur were detected.Furthermore,femur biomechanical parameters were determined by diaphysis three-point bending test and a new designed metaphysis bending test.The relationships between the biomechanical parameters and BMD or bone histomorphometry were assessed with Pearson correlations.ResultsThe femur BMD,bone histomorphometrical indexes(％Th.Ar,Tb.N,Tb.Th),and biomechanical parameters(maximum load,yield load and stiffness) of OVX group significantly decreased compared with Sham group.In metaphysis bending test,the mean difference of the maximum load(Fmax),yield load(Fy) between group OVX and Sham were significant higher than that in diaphysis three-point bending test.Positive correlations between biomechanical parameters and femur BMD or bone histomorphometry indexes were observed in both the diaphysis bending and metaphysis bending test.The biomechanical parameters in the metaphysis bending test showed stronger correlations with BMD and bone.ConclusionFemur metaphysis bending test could be used to evaluate the biomechanical properties of osteoporosis.When compared with diaphysis bending test,femur metaphysis bending test is more sensitive in evaluating the change of biomechanical properties of femur in osteoporotic rats.

Effects of pelvic orientation on the anteveration measurement of simulated acetabular cup / 中国组织工程研究

BACKGROUND: Acetabular cup orientation using a standard radiograph of the pelvis is quite common method to assess artificial hip replacement nowadays. Non-standardization of pelvic orientation affected accuracy of measurement results, and it is difficult to compare. OBJECTIVE: To make sure how pelvis tilting affect the anteveration of the cup and to elevate clinical accuracy and compare study comparability. METHODS: Designed a simulated acetabular cup with serial concentric circles which pass through the same polars and represent anteveration of 0°, 10°, 20°, 30°, 40°, Loaded the simulated acetabular cup at an inclination of 35°, 40°, 45°, 50°, 55° to6 cadaver pelves, Made the pelves tilt around the frontal axis and sagittal axis with 5° each time in a scope of+30°. Takestandard radiograph of the pelvis accordingly. Radiograph was photographed end frontal angle of dip was measured. RESULTS AND CONCLUSION: Pelvic tilt of about 1° causes measuring errors of anteveration 0. 61 °-0. 73°. The anteveration decreased at both acetabular cups when pelvic posterior tilt and at the acetabular cup that near the X-ray source as pelvic lateral tilt. The anteveration rose at both acetabular cups when pelvic anterior tilt and at the acetabular cup that away from the X-ray source as pelvic lateral tilt. During clinical evaluation, pelvic orientation effects on measurement results should be considered.

Design and verification of percutaneously puncturing apparatus for the vertebrae / 中国组织工程研究

BACKGROUND: Vertebroplasty or kyphoplasty is monitored under imaging apparatus. Standard entopic phase and standard lateral phase were obtained via repeatedly adjusting C-arm preoperatively. Puncturing angle was adjusted in experience, and time and X-ray exposure were significantly increased. OBJECTIVE: To design percutaneously puncturing apparatus for vertebrae in order to reduce X-ray exposure and shorten the operating time. DESIGN, TIME AND SETTING: A designing and verifying study was performed at the Department of Orthopaedics, the First Hospital Affiliated to Soochow University between October 2004 and March 2005. MATERIALS: Five samples of thoracic waist and lumbar vertebrae with soft tissues did not have abnormalities or defect. METHODS: CT scan and standard lateral image of 5 vertebrae specimen from T11 to L5 were got. Every "e" angle and "f" angle were measured and puncturing approaches were analyzed for kyphoplasty in thoracic and lumbar vertebrae. Percutaneously guiding instrument was only used on the left sides. The effect was analyzed and the exposure times were compared between the left and the right sides. MAIN OUTCOME MEASURES: Determination of puncturing approach, and X-ray exposure times between the left and the right sides. RESULTS: The entry point was at the superior-lateral 1/4 quadrant of the cross by a line passed the mid-point of two transverse process roots and a line passed the back edge of the superior articular process. In standard anterior posterior image, the entry points were at 2 o'clock on the left pedicle shadow and 10 o'clock on the right pedicle shadow respectively. The exposure times were 12.61±1.69 on the left and 23.19±1.60 on the right (P < 0.05).CONCLUSION: Ideal position can be arrived in puncturing according to the exact position, correct entry point and puncturing according to te exact position,correct entry point and puncturing angles.Application of percutaneously guiding instrument can sgnificantly diminish exposure time.

Content Determination of Baicalin in Xiaoer Zhike Granule by HPLC / 中国药房

OBJECTIVE: To establish the HPLC method for the content determination of baicalin in Xiaoer zhike granule. METHODS: YWG C18 (150 mm?4.6 mm,10 ?m) column was used and the mobile phase consisted of methnol-water-phosphoric acid (47 ∶ 53 ∶ 0.2) with the flow rate of 2.5 mL?min-1. The detection wavelength was set at 280 nm and injection volume was 10 ?L. RESULTS: The linear range of baicalin was 25～200 ?g?mL-1(r=0.999 6) with an average recovery of 99.57%(RSD=1.9%,n=6). CONCLUSION: This method is sensitive, simple and accurate for the quality control of Xiaoer zhike granule.

Biomechanical studies on gradient hydroxyapatite-coating / 中国矫形外科杂志

[Objective]To evaluate the interface biomechanical characteristics of a new kind of hydroxyapatite coating.[Method] Ten dogs underwent hermiarthroplasty of hip joint and were divided into 2 groups.One group was placed in Ti-6AI-4V femoral stem(Ti hip group),the second group was placed in HA-coated femoral stem(HA hip group).The second method was rod implant in condyles in both legs of each dog.Four matured dogs were selected.Eight Ti-6AI-4V rods(Ti rod group)were placed in lateral and medial condyle in left leg of each dog and eight HA-coated rods(HA rod group)were implanted in that of right leg of each dog.The dogs were sacrificed at 12 weeks after operation,and then the interface shear strength and imerface histological changes were evaluated.[Result]The Pust-out test showed that the average interface shear strengths of Ti hip group and HA hip group were(2.58?1.56)Mpa and(7.57?1.03)Mpa respectively.The interface shear strengths of HA hip group was significantly higher than that of Ti hip group(P

Differentiation into osteoblasts from marrow mesenchymal stem cells of rabbits transfected by human bone morphogenetic protein-7 gene / 中国组织工程研究

BACKGROUND: At present, bone morphogenetic protein (BMP) is the only cytokine characterized as the ability of osteoblast, and it can promote marrow mesenchymal stem cells (MSCs) differentiating into chondroblast and osteoblast.OBJECTIVE: To investigate the differentiation into osteoblast from MSCs of rabbits transfected by human bone morphogenetic protein-7 (hBMP-7) gene with genetic engineering technique. DESIGN: Single sample observation. SETTING: Department of Orthopaedics, the First Hospital Affiliated to Sun Yat-sen University. MATERIALS: pcDNA1.1/AMP-hBMP7 plasmid.METHODS: The experiment was completed at the Surgery Laboratory of the First Hospital Affiliated to Sun Yat-sen University from May 2004 to March 2005. MSCs of rabbits were cultured with whole bone marrow technique, transfected with pcDNA1.1/AMP-hBMP7 and pcDNA1.1/AMP plasmids respectively in vitro, and left the blank controls. Transcription and expression of transfected genes were detected so as to observe form and growth of cells. Component of calcium content in cytoplasm was measured and osteogenic phenotype was identified with alkaline phosphatase (ALP) staining, calcium salts staining and transmission electron microscopy (TEM).MAIN OUTCOME MEASURES: ① Form and growth of MSCs of rabbits; ② evaluation of expressive product; ③ results of ALP staining (Ca-Co technique); ④ results of chinalizarin staining; ⑤ results of TEM; ⑥ results of scanning electron m icroscopy (SEM); ⑦ assay of osteocalcin.RESULTS: hBMP-7 gene was contained in MSCs after transfection and expressed the relevant mRNA. Cellular form changed a little after expression of amid genes, but growth curve did not changed as compared with that in non-transfected group. Expression of osteocalcin was increased as compared with that in non-transfected group, and ALP staining and calcium salts staining of transfected cells were positive.CONCLUSION: Transfection of hBMP-7 gene can promote MSCs of rabbits differentiating into osteoblast.

Immunohistochemistry research of interface membrane around loosening hip prosthesis / 中国医师进修杂志

Objective Collecting the loosening periprosthetic interface-membrane, to discuss the mechanism of hip arthroplasty loosening. Methods The periprosthetic interface tissues of 29 hip arthroplasty revision cases from February 1995 to December 2003 were collected. The retrieved periprosthetic interface tissues were detected by immunohistochemistry. Some of them were studied by electronic microscope. Results (1)Transmission electronic microscope examination: the mitochondria swell. There were some substantia like lipid in the plasm of macrophages. Wear particles could be seen under scaning electronic microscope.(2)Immunohistochemistry: there were 22 IL-1? positive cases in cells of interface membrane. There were 29 IL-6 positive cases in cells of interface membrane. There were no positive results in TNF-? test. Conclusion (1)The wear particles of arthroplasty are important factors which cause biological reaction.(2)The interface membranes contain cytokine IL-1? and IL-6, which may play an important role in periprosthetic osteolysis and arthroplasty loosening.

Outcomes of primary total hip replacement in patients with ankylosing spondylitis / 中国医师进修杂志

Objective To review the characteristics and outcomes of primary total hip replacement(pTHR) in patients with ankylosing spondylitis(AS). Methods Eighteen patients (26 hips) with AS underwent pTHR from January 1991 to September 2003 were reviewed retrospectively. Sixteen patients (24 hips) were followed-up. The mean duration of follow-up was 85 months (ranging from 23 to 169 months). All patients were evaluated using Harris score standardization. Results There were 15 hips with hip ankylosis( 57.7%). The average time of the operation was 167.4 minutes (ranging from 90 to 350 minutes),the average volume of bleeding in the operation was 773.9 ml (ranging from 300 to 2000 ml),the postoperative average drainage was 488.6 ml(ranging from 50 to 1130 ml). The rate of excellent and good was 87.5 percent. Conclusion The pTHR is a very effective treatment for patients with AS. The perfect rehabilitation care is one of the main factors influencing the outcomes of pTHR for patients with AS.

Gene transfer mediated through adeno-associated virus type 2 induces transgenicexpression of bone morphogenetic protein-7 in adipose-derived adult stem cells in vitro / 中华创伤骨科杂志

Objective To construct vectors based on adeno-associated virus type 2 (rAAV2) carrying bone morphogenetic protein-7 (BMP-7) and observe their expression in adipose-derived adult stem cells, which can be served as a new gene therapy method and cell source for bone tissue engineering. Methods The coding sequence (1. 3 kb) of BMP-7 was amplified by PCR from the pcDNAl. 1 ( + ) plasmid containing the human BMP-7 cDNA. After purified, the gene fragments were cloned into a plasmid pUC18 and termed plasmid pUC18-hBMP7. The recombinant pUC18-hBMP7 was digested and further ligated to the pSNAV by T4DNA ligase and termed plasmid pSNAV-hBMP7. BHK-21 cells were transfected with the purified pSNAV-BMP7 plasmid according to a standard calcium phosphate precipitation method. The cells were isolated and the integrity of hBMP7 gene was determined by polymerase chain reaction (PCR) using the above PCR primers. To package the virus, stably transfected BHK-21 cells were subsequently infected with recombinant herpes simplex virus type 1 (rHSV-1). The collected cells were processed by chloroform treatment, PEG8000/NaCl precipitation and chloroform extraction for purification. The tiler was determined using quantitative DNA dot blots and the purity was examined by sodium dodecyl sulphatepolyacrylamide gel electrophoresis. Following infection with rAAV2-BMP7 at multiplicities of infection of 1?105 vector genomes per cell and subsequent culture, adipose-derived adult stem cells were assessed qualitatively for BMP7 production. Results The recombinant plasmid pSNAV-hBMP7 was identified by PCR and digested with restriction enzyme. Transfection showed an efficiency of 90 % in ADAS cells. BMP-7 expression in ADAS cells was identified by Western blot. Conclusions The hBMP-7 recombinant adeno-associated virus vectors can be successfully constructed in vitro and rAAV2-hBMP7 can infect ADAS cells.

Recovery law of hind limb function following complete spinal cord transection injury in rats / 中华创伤杂志

Objective To observe the recovery process of hind limb function following complete spinal cord transection injury and discuss corresponding mechanism. Methods The spinal cords of 15 SD rats were transected at T9 plane and a 3 mm spinal cord removed for a complete transection. The functional recovery of the hind limb was evaluated using CBS (combined behavioral score) and Basso Beattle Bresnahan (BBB) 1, 2, 4 and 6 weeks after injury. At the 6th week after injury, also experiment was done on histology, immunohistochemistry, motor evoked potential (MEP) of spinal cord and repeated transection. Results The hind limb function of the injured animals recovered at different degrees, most obvious at the 4th week and BBB was up to 12 at the 6th week. MEP result was related to the site of the stimulating electrode. No MEP was recorded when the stimulating electrode was placed above the injured site. But when the stimulating electrode was placed below the injury level, MEP was normal. The again transection of the spinal cord above the injury level took no effect on the recovered hind limb. However, again transection below the injury level resulted in complete paralysis. Histologic results showed that the injured site was filled with glial scars without axons. There existed a little scattered positive fibers of neurofilament protein 200 (NF200). Conclusions After complete spinal cord injury, there is a significant spontaneous recovery of the hind limb function that is a kind of autonomous functions of the injured distal spinal cord unrelated to repair of descending conducting fasciculus of the spinal cord. The distal spinal cord is intact in function.

Arthroscopic treatment of symptomatic discoid lateral meniscus / 第三军医大学学报

Objective To observe the effect of arthroscopic meniscectomy for symptomatic discoid lateral meniscus and the importance of early treatment. Methods Arthroscopic meniscectomy was performed on 29 patients (31 knees) with symptomatic discoid lateral meniscus. Partial meniscectomy was performed on 27 knees, subtotal meniscectomy on 4 knees with tear on the edge of meniscus. Results The operations on all 31 knees were successful without complications. The mean Lysholm score was 95.6 (87-100) during the follow-up, which was significantly higher than that before the operation (65.7, range 36-78; P

The transfection of bone marrow stem cell with Tet-on regulating system and the pilot study of doxycycline depending expression with Tet-on regulating system / 中华骨科杂志

Objective To determine the feasibility of using Tet-on regulatory system to transfect primary rabbit bone marrow stem cells, and to control the activities of the target gene. Methods The Tet-on regulatory system were used to transfect bone marrow stem cells by lipofectamine with the increasing concentration of doxycycline (Dox), the activity of the fluorescence caused by the expression of the target gene (the luciferase gene) which transfected to bone marrow stem cells with Tet-on regulatory system were analyzed. Results Plasmids DNA after being digested by enzymes and agarose electrophoreses were analyzed. The DNA segments were cored with the plasmid map. The two DNA segments with the size of 6.02 kb and 1.38 kb could be detected after the plasmid of pTet-on, 5.2 kb DNA segment could be seen after the plasmid of pTRE-luciferase was digested by Hind Ⅲ. With the increasing concentration of Dox, the activity of the fluorescence caused by the expression of the target gene increased gradually. Although the uninfected bone marrow stem cells were induced, the relative-luciferase-unit(RLU) value was almost the same as that of the blanket control. It showed that uninfected bone marrow stem cells were not induced by Dox. The RLU value in infected bone marrow stem cells before induction was slightly high, but similar with the blanket control. This experiment shed light on that infected bone marrow stem cells showed good response to the induction by Dox. Conclusion With the help of Lipofectamine, the cultured bone marrow stem cells can be transfected by Tet-on regulatory system successfully. The expression of the target gene transfected to bone marrow stem cells with Tet-on regulatory system could be regulated by Dox.

Effect of Light Weight-bearing Activity on Bone Mineral Density,Histomorphometry and Biomechanics in Ovarietomized Rats / 中山大学学报(医学科学版)

【Objective】To study the effect of light weight-bearing activity on postmenopausal osteoporosis.【Methods】36 female rats were randomly divided into 3 groups:① Sham,② Ovx (ovarietomized),③ Ovx+Im (ovarietomized and immobilized).All the group's maintained daily activity.And because of being immobilized,the right hind limbs of the third group lacked weight-bearing activity.12 weeks after ovarietomy,the BMD (bone mineral density),histomorphometry and biomechanics of the right femurs of rats were measured and analyzed.【Results】Comparing with the Sham group,the Ovx group's right femurs were manifested with the decrease of BMD,TBV (trabecular bone volume),MTT(mean trabecular thickness) and MCT(mean cortex thickness),while the increase of RS(resorption surface) and OS(osteotoid surface).Meanwhile their biomechanic nature declined.But statistically the BMD,MCT and the criteria of mechanical strength were not significant decrease.Otherwise,the Ovx+Im group's right femurs showed more apparent decrease of BMD,TBV,MTT and MCT.And the biomechanic nature was worse.Comparing with the Sham group,the BMD,MCT and the criteria of mechanical strength of the Ovx+Im group were statistically significant decreased.【Conclusion】If maintaining light weight-bearing activity,the ovarietomized rats were able to maintain relatively better bone quality.A lack of light weight-bearing activity wouldcause thedecline of bone quality.Thusthestudy suggested light weight-bearing activity was significantly effective on the prevention and treatment of postmenopausal osteoporosis.