Porous calcium phosphate cement induces osteogenesis of mesenchymal stem cells under microenvironment / 中国组织工程研究

BACKGROUND: The osteoinduction by biomaterials has been proven in various animal experiments. OBJECTIVE: To investigate the osteoinduction of porous calcium phosphate cement on bone marrow mesenchymal stem cel s. METHODS: Bone marrow mesenchymal stem cel s were isolated from rabbits aged 1 week in vitro and labeled by PKH-67 or PKH-26, respectively. Forty-eight adult New Zealand white rabbits were randomized into four groups and porous calcium phosphate cement was implanted into both sides of gluteus maximus in each rabbit. Then, 1 mL PKH-26-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into the superior gluteal artery branch at each side of gluteus maximus near the femur, and 1 mL PKH-67-labeled bone barrow mesenchymal stem cel s (1×1010/L) injected into tissues around the cement (group A); 1 mL PKH-26-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into the each side of superior gluteal artery branch (group B); 1 mL PKH-67-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into tissues around the cement (group C); the same amount of normal saline was injected into tissues around the cement (group D). At 3, 7 and 12 weeks after implantation, the cement and its surrounding tissues were extracted and detected by fluorescence microscope and Massion staining. Expression of bone morphogenetic protein 2 was analyzed by RT-PCR. RESULTS AND CONCLUSION: Under fluorescence microscope, PKH-26-labeled bone barrow mesenchymal stem cel s attached fast and distributed homogeneously; however, PKH-67-labeled bone barrow mesenchymal stem cel s attached slowly and exhibited a gradual y homogeneous distribution. Massion staining showed that ectopic new bone formation appeared to have an upward trend in al groups, and the area of new bones in groups A, B and C were larger than that of group D at different time points after implantation. There was a significantly higher expression of bone morphogenetic protein 2 in groups A, B and C compared with the group D at different time points after implantation (P < 0.05), and the expression was the highest in the group A (P < 0.05). In conclusion, the porous calcium phosphate cement can induce bone barrow mesenchymal stem cel s chemotaxis and osteogenetic differentiation. Besides, osteoblasts are differentiated from both the surrounding capil aries and body fluid, and capil ary-derived mesenchymal stem cel s occupy the important position.

The preparation and evaluation of tissue inducible nerve guide conduit / 生物医学工程学杂志

The objective of this research was to fabricate a novel tissue inducible nerve guide conduit, and to evaluate its biologic property. The microspheres were prepared with chitosan that encapsulated ligustrazine. The drug release of the chitosan microspheres was detected with application of the controlled release method in vitro. Chitosan microspheres were mixed with collagen to fabricate the tissue inducible nerve conduit, which were crosslinked with 2% genipin for 24h. Mechanical properties of the nerve guide conduit samples, including maximum load and breaking load, were measured using an Instron Series IX Automated Materials Testing System. The flexibility of the nerve guide conduit was determined with the texture evaluation instrument. Different methods, such as scanning electron microscope (SEM), light microscope (LMS) and immunofluorescence were used to analyze the spatial structure of the nerve guide conduit, the distribution of the microspheres, the state of the nerve duct combined with mesenchymal stem cells (MSCs), and the effect of the ligustrazine that released from chitosan microsphere on MSCs differentiation into nerve cells, respectively. The results showed that the chitosan microspheres had better releasing effect. The mechanical properties resultant nerve guide conduit were determined. The maximum load and breaking load of the genipin crosslinked samples were significantly higher than that observed with the non-crosslinkers, increasing to (0.76 +/- 0.15) N and (0.69 +/- 0.17) N from (0.23 +/- 0.09) N and (0.20 +/- 0.12) N for the non-crosslinkers (P < 0.01). The degradation rates of non-crosslinked and crosslinked by genipin were(58.62 +/- 7.59) mg and (9.23 +/- 2.47) mg, respec- tively. This had a statistical significance (P < 0.01). The average linearities in dry and hygrometric state of the nerve guide conduit were (0.597 +/- 0.012) LC and (0.333 +/- 0.015) LC, respectively, which also had statistical significance (P < 0.01). The flexibility in the hygrometric state of the nerve guide conduit was better than that of the dry. SEM analysis of the samples demonstrated that the structures of the nerve guide conduit were significantly changed in crosslinking samples, the microspheres were uniformly distributed on the surface of scaffold, the ligustrazine that released from the chitosan microspheres could promote MSCs to express NSE and MAP2 that were the relevant marker molecule of nerve cells. The nerve guide conduit is combined with MSCs, which promote MSCs proliferation and NSE expression by the ligustrazine that released from the chitosan microspheres. The conduit has better biological compatibility and tissue inducible function.

Treatment of foot injury with free medial sural artery perforator muscle flap / 中华全科医师杂志

This observation was to assess the treatment effects of free medial sural artery perforator muscle flap on foot reconstruction.Seven patients(6 men,and 1 woman;age 19 to 46 years,mean 33) with soft tissue defects on the foot underwent surgical procedures by using free medial sural artery perforator muscle flap.The coverage of the muscle flaps was performed by a meshed split-thickness skin graft.The donor site Was closed.Median follow-up Was 2.5 years(range 7 monks to 5.5 years).All the muscle flaps and skin grafts survived without major complications,and no morbidity was found at the donor sites.The muscle flaps seem to have advantage in blood supply,vascular anatomy and pedicle length,and may be helpful in the mpmr of soft tissue defects on the foot.

Defects of fore foot repaired by reverse medial dorsal neurocutaneous flap of foot in emergency / 中华显微外科杂志

Objective To investigate the possibility of repairing the defects of fore foot by reverse medial dorsal neurocutaneous flap on foot in emergency.Methods Flap was designed along medial dorsal cutaneous nerve of foot,the axis of the medial branch was the line between lateral part of malleolar middle point and medial part of first metatarsophalangeal joint,and the axis of the lateral branch was the line between middle point of two malleolars and the tip of the great toe webspace,the pedicle located on the distant part of the foot.Based on the size of wound,the flap was cut off from the deep fascia layer,and medial dorsal cutaneous nerve of foot was anastomosed with nerve of digitales plantares proprii.All patients were operated in emergency.Results Eleven patients with defect of fore foot were perfectively recovered and all the wounds healed primarily.The appearances and functions of the foots were satisfactory,with two point sensation of 2-3 cm after 6-11 months postoperatively and without any skin fester.Conclusion Medial dorsal cutaneous nerve of foot has advantages as follows:simply procedures,avoidance of sacrificing major arteries,less harm to donor area,good recovery of sensation.So it is a good method to repair tissue defects of fore foot.

Perioperative management and effect analysis of total hip arthroplasty in elder patients with developmental dysplasia of the hip / 中国矫形外科杂志

[Objective]To study the perioperative management and effect of total hip arthroplasty (THA) in elder patients with developmental dysplasia of the hip (DDH). [Methods]THA was applied in 24 patients (32 hips) who sufferring osteoarthritis and femoral head necrosis due to developmental dysplasia of the hip. The patients ranged from 70 to 82 years old with an average age of 74.3,and they all had metabolic diseases or more than one organ dysfunctions. The patients fulfilled the conditions of the surgery after sufficient perioperative period preparation.[Results]The follow-up time was from 2 to 8 years (averaged 3 years).Cardiopulmonary function was improved in all patients and the artificial joints were stable. And the patients could walk stably and powerfully without pain and deformity of the hip. The average Harris score after the operation was 87.2 points,and it was higher than 38.5 points before the operation.[Conclusion]For the reason of osteoarthritis and femoral head necrosis due to DDH,the patient's activity decreased,and so with their organ functions. And these patients always had metabolic diseases.All these can affect the safety and the outcome of THA. Therefore,sufficient perioperative management is as important as the surgery technique to obtain a stable,painless and functional joint in these patients.

Experimental investigations of macroporous calcium phosphate cements/bone morphogenic protein composite in repairing bone defects / 中国矫形外科杂志

[Objective]To analyze the biodegradation properties and active osteogenesis features of implanted composites of gelatin microspheres(GMs) impregnated with calcium phosphate cement(CPC) and recombinant human bone morphogenetic protein-2(rhBMP-2) in bone defect.[Method]rhBMP-2 loaded gelatin microspheres was incorporated in rhBMP-2/CPC during setting.Thirty rabbits were divided into groups A,B and C(10 each).The rhBMP-2/GMs /CPC,GMs/cpc and rhBMP-2/cpc was implanted into the rabbits of group A,B and C,respectively.The biodegradation properties and active osteogenesis features of implanted composites bone substitute was evaluated by radiography,histology,bone mineral density(BMD)after the composites were implanted into the bone defects at rabbit radius for 6,12 weeks respectively.[Result]Significant implant resorption and bone ingrowth were observed in all rhBMP-2/GM/CPC treated defects while the defects treated with rhBMP-2/CPC implants showed slight resorption of CPC and the defects treated with GM/CPC implants showed slight formation of new bone.[Conclusion]The result of this study suggested that the rhBMP-2/GMs/CPC composite could be used as material for bone graft substitute.

Combination of calcium phosphate cement and micromorselized bone for repairing rabbit radius defect / 中国矫形外科杂志

[Objective]To confirm the effect of combination of calcium phosphate cement and small amounts of autoallergic micromorselized bone for reparing bone defect and provide the basis for clinical use.[Method]The animal models of bilateral radius defect were created by surgery on Japan white big ear rabbits.The combination with a ratio of 3 to 1 in one lateral leg was implanted in experimental group,and calcium phosphate cement was used in the control group.The X-rays,bone density,and maximum torsional moment were carried out at different time points,and osteogenesis and degradation of the materials in the two groups were analyzed.[Result]Enhancement of osteogenesis was found in the experimental group,and the materials were enclosed significantly by bony callus at the 8~(th) week,the defects were repaired and the materials were degraded completely at the 16~(th) week.The bone mineral content in the experimental group was higher than that in the control group(P

Effect of vacuum sealing drainage on bacteria and microcirculation of acute explosion wounds / 中国矫形外科杂志

[Objective]To observe the effect of vacuum sealing drainage(VSD) on bacteria and microcirculation of acute explosion wounds in pigs.[Method]Twelve blast wounds,created by explosion of a specific type of electric detonations which were fixed at 1 cm over the skin of the hips of six Lanzhou healthy pigs(30-40 kg),were divided into two matched groups.Debridement was performed at 6 hours after injury.Group A was treated with conventional dressing change,and group B was treated with VSD under the pressure of-20kPa.Tissue specimens collected from different sites of the wound bed before and at 12,24,48,72 hours after treatment,and experienced bacteria counting.The microcirculation of the blast wounds was examined by color B-mode ultrasonic diagnostic equipment before and 72hours after treatment.[Result]The difference of wound bacteria loads between group A and group B was statistically signficant at different time points.Bacteria loads in group B were increased to 105cfu/g at 48 h after treatment,compared with group A at 24 h.No signal of blood flow in blast wound was found before treatment.In contract,the blast wound had plenty of signals of blood flow in group B.[Conclusion]VSD could reduce the bacteria loads,and delay the time of infection.Meanwhile it improved the microcirculation of the acute blast wound.

Experimental study of calcium phosphate cement and combined morselized bone in vitro / 中国矫形外科杂志

[Objective]To study the combination of calcium phosphate cement(CPC) and morselized bone and their optimum mixing ratio. [Methods]Bilateral nemora of macro-ears rabbits were made into morselized bone.There were two groups:experimental group and control group.In the experimental group,the ratios of morselized bone to CPC were 1 to 1,1 to 2,1 to 3,1 to 4 and 1 to 5.In the control group CPC was used after it was solidified.The maximum compression strength and solidified time of the materials in experimental and control groups were tested.The cell multiplication was evaluated by MTT after mesenchymal stem cells were cultivated.[Results]The cell multiplication in materials mixed with ratios of 1 to 2 and 1 to 3 was better than those in the materials mixed with the other ratios by MTT.It indicated that there was a significant difference(P

Experimental study on nerve allografts stored in green tea polyphenol solution / 中国矫形外科杂志

[Objective]To explore the outcome of repairing nerve defects with nerve allografts stored in green tea polyphenol solution.[Method]Forth-eight male mice were randomly divided into 4 groups of nerve grafting,with 12 rats in each group.A 1.0 cm sciatic nerve segment,5 mm away from infrapiriform foramen,was removed and repaired by 4 kinds of nerve allografts.Group A:autografts.Group B:allografts.Group C:cryopreserved nerve allografts.Group D:nerve allografts stored in green tea polyphenol solution.At 6 weeks and 12 weeks,a series of examinations were performed,including the gross appearance,electrophysiological test,histological observation,electron microscopic study and quantitative analysis with image analysis system.[Result]All the parameters of groups A and D were better than those in groups B and C(P

Development of macroporous calcium phosphate cements as bone substitutes by using gelatin microspheres / 中国矫形外科杂志

[Objective]To develop macroporous calcium phosphate cements(CPCs) by incorporating the gelatin microspheres(GMs) and to evaluate the performance of the composite as a bone substitute in vitro and in vivo. [Methods]GMs were prepared by improved emulsified cold-condensation method and macroporous CPCs were developed using GMs with three different weight ratios (0%,2.5% and 5%). The porosity and the compression strength of the three composites were measured to determine the proper weight ratio of GMs. The morphologic changes of osteoblasts were examined with scanning electron microscope at two days after the cells were seeded on the CPCs and GMs/CPCs. The cells were also cultured with different leaching liquor of three kinds of materials (0%,2.5% GMs/CPCs and polystyrene).Cell viability analysis was performed by MTT assay,and alkaline phosphatase was measured with alkaline phosphatase kit. At six months after implanted in the goat vertebre ,the samples with CPCs or GMs/CPCs were obtained and evaluated by X-ray image and histological anatomy.[Results]Porosity of the GMs/CPCs increased with the increase of GMs,but compression strength decreased. The proliferation and differentiation of the osteoblasts were enhanced with the 2.5% GMs/CPCs compared to the CPCs. In vivo study showed that the degradation of GMs/CPCs was improved.[Conclusion]Macroporous calcium phosphate cements can be developed by incorporating gelatin microspheres,and biocompatibility and degradability of the composite can be enhanced. The composite can be used as a bone substitute under non-loaded circumstances.

Macroporous,quik degradatable calcium phosphate cement / 中国矫形外科杂志

[Objective]To investigate the effect of an effervescent-sucrose on the properties of calcium phosphate cement. [Method]The sucrose particles were mixed with CPC powder at sucrose/(sucrose+CPC powder) mass percentage of 0%,10%,20%,30%,40%.The samples were characterized by compressive strength,X-ray diffraction,SEM techniques and degradation in vivo.[Result]The samples decreased on the mechanical properties and increased on the rate of macropore and total porosity,they were effected significantly among groups by added effervescent(P

Efficacy of deproteinised cancellous bone combined with BMP and fibrin in healing of rabbit segmental radial defect / 中国矫形外科杂志

[Objective]To repair segmental bone defect with the composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin.[Method] Bone defects were created in 36 New Zealand rabbits on the bilateral radii and treated with three kinds of implantations:A,composite of deproteinised cancellous bone,BMP and fibrin;B,of deproteinised cancellous bone;C,blank control.The defects were observed by entgenography,optical microscopy,and electron-microscopy at 2,4,8,12,16 weeks.[Result] The defects treated with A implantation regenerated much more new bone and bridged earlier than the defects treated with B implantation and got completely repaired 16 weeks after operation.The defects with B and C implantation couldn't get osseous tissue healing.[Conclusion]The composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin can be effectively used to repair segmental bone defect.

Various surgical approach for treatment of scapular neck and body fratures and analysis of the clinical results / 中国矫形外科杂志

[Objective]To study various surgical approaches to the treatment of scapular neck and body fratures,and evaluate the clinical results.[Method]From January 1996 to December 2006,thirty-two cases with scapular neck and body fratures including 21 males and 11 females with age range from 18-56 years (mean 29 years) that had been admitted to the author's hospital were retrospectively analyzed.On the basis of the fracture patterns,straight incision along lateral border of the scapula,posterior approach,Judet approach were performed with plates or lag screws for open reduction and internal fixation.[Result]All cases were followed up for a period of 8-22 months.The mean time of bone union was 6-8 weeks.According to Hardegger's evaluation,22 cases showed excellent results,7 good,2 fair,1 poor.[Conclusion]Open reduction and internal fixation are emphasized to the severe separated scapular neck and body fractures.Straight incision along lateral border of the scapula,posterior approach or Judet approach can be chosen on the basis of the fracture patterns.Most scapular neck and body fractures can be treated by straight incision approach along lateral border of the scapula.This surgical approach can provide exposure of the fratures directly with saved surgical time and attain perfect reduction and fixtion with less trauma.

One-stage corpectomy for the serious spinal cord compression from vertebral tuberculosis in the absence of neurologic deficits / 中国矫形外科杂志

[Objective] To study the mechanism and clinic characteristic to the serious spinal cord compression from vertebral tuberculosis in the absence of nenrologic deficits.[Method]A total of 15 patients with serious spinal cord compression from vertebral tuberculosis in the absence of neurologic deficits were treated by one-stage debridement,lilac grafting and internal fixation.The clinical characters were retrospectively analyzed.[Result]All these patients had no sinus formation and no recurrence of spinal tuberculosis during average the follow-up of 3.8 years(range:6 months to 7 years).In 5 cases with incomplete paraplegia,3 cases improved 2 grades,1 case was no change and 1 case became serious.[Conclusion]The serious spinal cord compression from vertebral tuberculosis in the absence of neurologic deficits has a long history in illness,the spinal cord is in crisis condition even it can get adjustment by itself.The early one-stage treatment of debridement,iliac grafting and internal fixation can guarantee the restore the spinal cord and spine stability.

Spinal tuberculosis with focus-healed kyphosis and compression of spinal cord in thoracolumbar region / 中国矫形外科杂志

[Objective]To explore the treatment method of Spinal tuberculosis with focus-healed kyphosis and compression of spinal cord in thoracolumbar region.[Method]Seventeen cases were treated surgerically by single stage procedure,including posterior fusion,posterior instrumentation,decompression of spinal canal and interbody autografting.[Result]All patients were followed up from 9 months to 7 years postoperatively.The solid fusion was showed radiologically in 2.8 months at posterior autografting and in 3.3 months at interbody autografting on the average.The anteriolateral decompression of spinal canal was performed on 6 cases,completely recovered in 1 case,partially recovered in 3 cases and bad result in 2 cases.[Conclusion]Spinal tuberculosis with focus-healed kyphosis and compression of spinal cord in thoracolumbar region may show little spinal symptom clinically.The purpose of treatment is to provide rigid fixation and good stability of spine.

Fibrin glue/bone morphogenetic protein complex plus slow-release gentamicin for repairing infected bone defects in rabbits / 中国组织工程研究

BACKGROUND: Chronic osteomyelitis is difficult to manage clinically, and two or more operations were commonly needed. No satisfactory method for one-stage repair has been currently available.OBJECTIVE: To examine the possibility of using fibrin glue(FG) as the common carrier for both bone morphogenetic protein(BMP) and gentamicin for one-stage repair of infected bone defects.DESIGN: A completely randomized controlled experiment.SETTING: Center of Orthopaedic Surgery, Lanzhou General Hospital of Lanzhou Area Command of of Chinese PLA.MATERIALS: The experiment was conducted using 48 healthy adult Chinchilla rabbits of either sex on normal diet with body mass of 1.9 to 2.4 kg,provided by the Institute of Biological Products, Lanzhou, Gansu Province.INTERVENTIONS: Animal models of chronic osteomyelitis were established in 48 Chinchilla rabbits, and after thorough debriding of the wounds,an elongated semicircular bone defect was induced 1.5 cm to the medial proximal metaphysis in the tibias. Three treatments were subsequently given with FG, MP and gentamicin complex(Group A), FG/BMP complex(Group B), and nothing(control group, Group C), respectively.MAIN OUTCOME MEASURES: The general conditions of the rabbits were observed postoperatively. Bacterial culture of the bone specimen, bacterial counting, X-ray and histological examination were performed.RESULTS: Rabbits in Group A exhibited obviously better infection control and greater regenerated bone mass than those in Group B, and no significant difference was noted in infection control between Groups B and C, the latter group showing poor bone defect repair.CONCLUSIONS: FG, BMP and gentamicin complex helps to control infection and promotes bone formation, and can be used to repair bone defects caused by infection and open injury with severe contamination.

Analysis of the expression of bcl-2 in osteogenic tumor and tumor-diseases / 临床外科杂志

Objective To investingate the expression method of bcl-2 and it's significance in osteogenic tumor and tumor-like diseases.Method The protein of PCNA, p53, Fas and bcl-2 were examined immunohistologically in osteosarcoma, ossifying fibroma, fibeous dysplasia of bone and normal bone callus. The results were analysed combing with the information of metastasis and hisomorphology.Results PCNA and p53 were highly expressed in low-differentiated osteosarcoma, bcl-2 were highly expressed at high-differentiated osteocoma and ossifying fibroma. When PCNA, p53 and bcl-2 were all expressed at high level, the metastasis rate was high, when only bcl-2 was expressed at high level, the progmosis was better. Conclusion The mechanism for benign and malignant tumor are different, the benign and low-degree malignant tumor may be caused by over accumulated mutation cells sipported by high level of bcl-2, while malignant tumor may be the result of multi-gene cooperation abnormally.

Magnetic resonance imaging and pathology of soft tissues penetrating wounds in pig thigh shot by domestic-made 95 type rifle / 解放军医学杂志

Objective To analyze the magnetic resonance imaging(MRI) appearance and pathological changes of pig thigh of soft tissues after been shot by rifle,so as to offer a theoretical foundation for wound management in early stage of gunshot injuries.Methods Seventeen adult pigs were intravenously anesthetized and suspended in supine position,the pigs were shot in 10 meters away by domestic-made rifle of 95 type.The wound limb were undergone 1.5T MRI scans and histological observation at 2h,6h,12h,24h,48h,9day,and 18day after shot injury.Results The wounded tissues included four areas of different pathological changes:primary ballistic cavity,coagulative necrosis area,tissue disruption area and tissue distortion area.The thickness of coagulative necrosis area was about 1 to 3 millimeters,which showed double-hypointense signal phenomenon in both T2 weighted image and enhanced T1 weighted image.The tissue disruption area and part of tissue distortion area showed double-hyperintense signal phenomenon in both T2 weight image and enhanced T1 weighted image.Conclusion Penetrating gunshot wound in soft tissues of hind limb can be divided into four areas:primary ballistic cavity,coagulative necrosis area,tissue disruption area and tissue distortion area.MRI can clearly show primary ballistic cavity and coagulative necrosis area.Tissue disruption area and tissue distortion area are hyperintense signal areas on the outside of the primary ballistic cavity,which can be distinguished clearly by pathalogical observation,but tissue disruption area and part of tissue distortion area are undistinguishable by MRI.

Correlative Investigation of Lumbar Lordosis in Chronic Low Back Pain Patients / 实用放射学杂志

Objective To investigate the correlation between the prevalence of chronic low back pain(CLBP)in cold plateau region in young men and the lumbar lordosis angle (LLA) on X-ray plain film.Methods Questionnaire, clinical findings, physical status and LLA measurement were obtained in 163 cases of different occupational young men.The relation between CLBP,body mass index(BMI) and LLA were studied.There were 77 cases of tankmen,54 cases of artillerists,32 cases of local resident(age 17~28 years). Results In 163 young men ,there were 63 cases with CLBP ( 38.8% ) . CLBP in tankmen was more frequency ( 47.0% ) than that in artillerists and local resident (P