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Objective To evaluate the application value of ultrasound in vascularization of different artificial bones . Methods A total of 15 New Zealand rabbits were utilized for model establishment of classic segmental bone defect in bilateral radius . Recombinant human bonemorphogenic protein-2 ( rhBMP-2 ) coralline hydroxyapatite(CHA) and CHA were implanted into left and right limbs . Each CHA was divided into 4 equal parts which were examined with conventional ultrasonography and contrast-enhanced ultrasonography( CEUS ) on 3 d ,7 d ,11 d ,15 d ,30 d and 45 d respectively . CEUS quantitative was performed by time-intensity curve(TIC) ,which parameters including the basic intensity(BI) ,peak intensity (PI) ,increased signal intensity ( ΔSI) and time to peak ( TTP) . Then the results were analyzed and compared to pathology . Results Within the same duration ,the vascularization degree in rhBMP-2 group was stronger than that in the ordinary group with advanced vascularization time . Positive correlation was detected between ΔSI and time of both groups ( r =0 .938 ,0 .890 ;P =0 .000) ,and negative correlation was found between BI/PI or TTP and time ( BI/PI: r = -0 .798 ,-0 .899 ; P = 0 .000 ;TTP= r -0 .874 ,-0 .868 ;P = 0 .000 ) . No statistical significance was observed among four observation points of both CHA ,which indicated no obvious difference in vascularization degree of each observation point . Conclusions The structure of bone graft can be clearly displayed by conventional ultrasound ,and CEUS is able to show the early blood perfusion in two CHA grafts and to accurately evaluate the difference of CHA microvascular growth before and after rhBMP-2 application . The combination of these two techniques is a promising approach of evaluating bone graft vascularization in clinical practice .
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Objective To investigate the osteogenic ability of dextran sulfate/recombinant human bone morphogenetic protein-2/chitosan (DS/rhBMP2/CS) nano microspheres combined with coralline hydroxyapatite (CHA) in repair of segmental bone defects.Methods DS/rhBMP2/CS microspheres prepared by ionic crosslinking method were adsorbed into CHA by lyophilization.Seventy-two New Zealand rabbits were randomly divided into 3 equal groups after they had been made into models of bone defect at the right radius.The defects in the 3 groups were implanted respectively with CHA,rhBMP2/CHA and DS/rhBMP2/ CS/CHA.Another 18 animals served as a blank control group.Blood and bone samples were obtained at 4,8 and 12 weeks after implantation.The serum BGP was detected,and the bone grafts were scanned by micro-CT for calculation of volume ratio of the new bone.Hematoxylin and eosin (HE) staining was performed after bone decalcification.Results All the 72 animals recovered well without any infection or graft exposure.Gross observation at postoperative 12 weeks showed that the DS/rhBMP2/CS/CHA group was the best in the quality,quantity and strength of the new bone,as well as in the healing of bone defects.The serum levels of bone gamma-carboxyglutamic-acid-containing protein at all time points in the DS/rhBMP2/CS/CHA group were significantly higher than those in the CHA and rhBMP2/CHA groups (P ＜ 0.05).Micro-CT scanning demonstrated obvious progress in bone formation,cortical bone and marrow cavity at all time points in the DS/rhBMP2/CS/CHA group which showed significantly faster bone reconstruction synchronized with material degradation and significantly higher volume ratio of the new bone than the other 2 groups (P ＜ 0.05).Histological examinations showed better morphology of mature cortical bone and new marrow cavity at all time points in the DS/rhBMP2/CS/CHA group than in the other 2 groups.Conclusion Since DS/rhBMP2/CS/CHA possesses a better mechanism of sustained-releasing rhBMP2 to induce bone formation because of its reticular and hole-hole-connected structure,it may perform better in repairing segmental bone defects than simple CHA or rhBMP2/CHA.
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Objective To compare the biomechanical stability of 4 internal fixations in treatment of acetabular fracture of the lower anterior column through finite element analysis.Methods One normal adult male pelvis was subjected to 0.7mm thin-section CT scanning and 379 CT pictures were obtained.Finite element modeling software was used to establish internal fixation models for acetabular fracture of the lower anterior column,including lag screws (A),anterior column reconstruction plate (B),subcutaneous plate not crossing the pubic symphysis (C) and subcutaneous plate crossing the pubic symphysis (D).Finite element analysis was carried out to compare the biomechanical differences among the 4 internal fixation models which were subjected to the same loading conditions at both standing and sitting positions.Results At standing and sitting positions,the maximum displacement and the mean node displacement of fracture lines were the greatest in group A (0.558 mm and 0.462 ±0.092 mm at standing;0.634 mm and 0.473 ±0.108 mm at sitting),the smallest in group D (0.512 mm and 0.425 ±0.083 mm at standing;0.031 mm and 0.025 ± 0.004 mm at sitting),and in between in group B (0.513 mm and 0.432 ±0.085 mm at standing;0.630 mm and 0.466 ± 0.109 mm at sitting) and in group C (0.514 mm and 0.433 ± 0.085 mm at standing;0.627 mm and 0.464 ± 0.107 mm at sitting).At both standing and sitting positions,the maximum stress at the fracture line was the greatest in group D (10.519 MPa and 24.879 MPa),the smallest in group A (3.254 MPa and 8.954 MPa),and in between in group B (4.873 MPa and 9.431 MPa) and in group C (4.384 MPa and 10.128 MPa).Conclusions In treatment of acetabular fracture of the lower anterior column,subcutaneous plate crossing the pubic symphysis may result in the greatest biomechanical stability,lag screws the smallest biomechanical stability,and anterior column reconstruction plate and subcutaneous plate not crossing the pubic symphysis the moderate biomechanical stability.
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BACKGROUND: Scholars disagree with each other about the small saphenous vein effects on skin flap and how to dispose vascular proximal pedicles.OBJECTIVE: To analyze effects of different methods of the small saphenous vein disposal on flap survival using sural neurocutaneous island flap retrograde metastasis for repairing defects of soft tissue of instep, heelstick and ankle.DESIGN, TIME AND SETTING: The case control observation experiment was performed at the General Hospital of Guangzhou Military Area Command of Chinese PLA from March 1998 to April 2007.PARTICIPANTS: A total of 56 patients with defects of soft tissue of instep, heelstick and ankle were divided into 2 groups,small sapbenous vein deligation in proximal pedicle flap group (group A) (n=38), and proximal small saphenous vein and great saphenous vein or tributaries at recipient site anastomosis flap group (group B) (n=18).METHODS: During sural neurocutaneous island flap retrograde metastasis for repair,(3.5×4.0)cm-(4.0×4.5) cm flap was obtained in 35 cases, and (4.0×4.5) cm -(10.0×12.0) cm in 21 cases.MAIN OUTCOME MEASURES: Outcome of flap survival at different incision area and implanted methods.RESULTS: No vein articulo occurred in 21 cases, which flap areas were (4.0×4.5) cm -(10.0×12.0) cm. Five of 35 cases which flap areas were (3.5×4.0) cm -(4.0×4.5) cm developed vein articulo.The necrotic rate of flaps in group B was significantly lower compared to the group A (P=0.017 67).CONCLUSION: When the area of skin flap is smaller than (4.0×4.5) cm, the proximal end of the small saphenous vein should be anastomosed with the great saphenous vein or tributaries connecting with the great saphenous vein at recipient site.The small saphenous vein is not a superficial vein, which only cross the skin flap, but it has trophic action on the skin flap.
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BACKGROUND: Migu tablet, a Chinese drug for kidney invigorating, is effective on preventing and treating osteoporosis, but the concrete mechanism of pharmacology is still not clear. Transforming growth factor-β1(TGF-β1) is an important cytokine, which can regulate bone resorption and formation.OBJECTIVE: To investigate the effect of kidney invigorating recipe on mRNA expression of TGF-β1 of osteoblast.DESIGN: A completely randomized controlled study was conducted.SETTING: Department of Traumatic Orthopedics, Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology.MATERIALS: This experiment was conducted at the laboratory for bone metabolism of integration of Chinese and western medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from May 2003 to April 2004. Experimental rats: Totally 16 newborn SD rats of clean degree were involved. Experimental drug: Medical liquor of Migu tablet was prepared in the Department of Traumatic Orthopedics,Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. The subscription was mainly composed of Chinese herbs such as Herba Epimedii, Cortex Eucommiae, Semen Juglandis,Radix Rehmanniae, Radix Achyranthis Bidentatae. and so on. Positive control drug: which was recombinant basic fibroblastic growth factor (rbFGF), was purchased from Beijing Banding Company. Negative control group was subdivided into negative control of probe and antibody METHODS: 100,1 000,5 000,10 000 mg/L Chinese herb Migu tablet liquor for kidney invigorating and positive control drug 5 μg/L rbFGF were added into the osteoblasts of cranial bones of newly born SD rats separated and cultured in vitro. 24 hours later, nuclear acid molecular in situ hybridization of osteoblasts were analyzed by self-made digoxin-labeled TGF-β1 cDNA probe . The mean absorbance of positive particles representing the mRNA expression of TGF-β1. A total of 40 osteoblasts were randomly chosen from each group under 200-fold amplification. The average absorbance of hybridized particles of the cells was measured with TJTY-300 automatic image analyzer.MAIN OUTCOME MEASURES: mRNA expression of TGF-β1 in osteoblasts of each group.RESULTS: Automatic image analyzer showed that the TGF-β1 mRNA expressions of Migu liquor groups whose concentration were 5 000 mg/L and 10 000 mg/L were respectively 1.18 times and 1.30 times that of control group, with a significant difference. [The mean absorbance's of hybridized particles of the cells in the 5 000,10 000 mg/L Migu liquor groups and negative control were 0.213 67±0.015 00,0.237 03±0.021 73,0.181 27±0.015 28 ,respectively, P ＜ 0.05 and P ＜ 0.01].Although the mean absorbance ( 0.254 45±0.020 81)of the hybridized particles of the cells in the 5 μg/L recombinant rbFGF was higher than those of 5 000,10 000 mg/L Migu liquor groups, but there was no significant difference(P ＞ 0.05).CONCLUSION: Migu tablet for kidney invigorating can stimulate the secretion and synthesis of TGF-β1 in osteoblasts, thus promote bone formation and inhibit bone resorption.
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BACKGROUND:The therapeutic effects of donkey-hide glue reinforcing bone oral solution on osteoporosis have been determined, but the exact effective mechanism is to be approached. OBJECTIVE: To investigate the effects of donkey-hide glue reinforcing bone oral solution (DGRBOS) medicated serum on osteoprotegerin (OPG)and its ligand(OPGL)mRNAexpression of osteoblast in fetal rats and explore the molecular mechanism of treating osteoporosis with DGRBOS. DESIGN: A randomized controlled trial. MATERIALS: The experiment was carried out from June 2003 to October 2004 in Bone Metabolic Laboratory of Department of Integrative Chinese and Western Medicine, Affiliated Hospital of Tongji Medical College,Huazhong University of Technology and Science. Totally 30 3-month-oldWistar rats (15 males and 15 females) were randomly divided into 3 groups, I.e. DGRBOS group, estrogen group and control group, with 10 rats in every group. 12 clean newborn SD rats were selected to isolate and cul ture osteoblast. METHODS: ①After intragastric administration for 7 days, medicated serum was prepared respectively from the three groups. ②Skull osteoblast isolated from newborn SD rats was made into single cell suspension, then after digestion and passage, the subcultured osteoblast cell was made into cell suspension. The cultured osteoblasts were divided into 5 groups and given equal volumes of drug liquor. The DGRBOS group was given DGRBOS-medicated serum at the concentration of 100, 500 and 1 000 g/L which was diluted by nutrient solution; the estrogen group was given tibolone-medicated serum of 100 and 1 000 g/L; the control group was givenonly culture fluid. Meanwhile every group was given calf serum (100 g/L) for further culture. ③The osteoblast proliferation was measured by antigenic MTT colorimetric analysis and 3H-TdR penetration method. The in tra-cellular BGP contents were evaluated by radioimmunity .The mRNA expression of OPG and RANKL in osteoblast was analyzed by Rt-PCR. ④ One-way analysis of variance was applied to compare data among groups. MAIN OUTCOME MEASURES: mRNA expression of OPG and PAN KL in osteoblasts from fetal rats after intervention by medicated serum ofDGRBOS or Livial. RESULTS: ①The osteoblast proliferation measured by antigenic MTT colorimetric analysis and 3H-TdR penetration method showed that the proliferation in the DGRBOS group and tibolone group was enhanced moresignificantly than that in the control group (P ＜ 0.05-0.01), and reached maximal effect at the concentration of 500 g/L (P ＜ 0.01), but when the concentration was over 500 g/L, the effect tended to saturate. The medicated serum with all concentrations from DGRBOS and estrogen groups could increase the contents of BGP in osteoblasts (P ＜ 0.05). ②The mRNA expression of OPG reached the peak when the DGRBOS medicated serum was 1 000 g/L, and was obviously higher than that at the concentration of 100 and 500 g/L (P ＜ 0.05). The expression in DGRBOS group at the concentration of 1 000 g/L and in the estrogen group at the concentration of 100 and 1 000 g/L was apparently higher than that of the control group (P ＜ 0.01). ③The mRNAexpression of RANKL was the highest in DGR BOS group with 1 000 g/L concentration, and was markedly lower than that of the concentration of 100 and 500 g/L (P ＜ 0.05). The expression in DGRBOS group at the concentration of 1 000 g/L and in the estrogen group at the concentration of 100 and 1 000 g/L was noticeably lower than that in the control group (P ＜ 0.01).CONCLUSION: ①The DGRBOS could remarkably enhance osteoblast proliferation in dose-dependent and a dose-saturable manner, and the effect was close to that of tibolone. ②Partial mechanism of DGRBOS in treating osteoporosis might be promoting osteoblast proliferation and regulating OPG/RANKL expression.
