Objective:To observe the destructive characteristics of the bovine liver induced by focused ultrasound clamp technique.Methods:A focused ultrasound surgical clamp(FUSC) consisted of two transducers fixed on a forceps-like handle.The directions of focused ultrasound beams were opposite,with the same central axes.The thickness of bovine liver in vitro ranged from 4 to 10cm.Ultrasound energy was continuously delivered to ablate the liver with a frequency of 1.6MHz,and spatial peak pulse average acoustic intensity(ISPPA) of 12 000W/cm2.The characteristics of complete coagulation necrosis and exposure time were measured after FUSC exposure,and pathological changes in treated bovine liver tissue were observed.Results:FUSC induced complete coagulation necrosis of predetermined bovine liver targets.The shape of coagulation necrosis was corresponded with focused ultrasound beam,with 2.72～3.20cm in length and 1.44～1.80cm in width.However,under the same exposure energy,exposure time for complete necrosis increased,as the thickness of the liver increased.Conclusion:FUSC can induce complete coagulation necrosis of predetermined bovine liver targets.This study would provide a novel surgical instrument for hepatectomy.

Objective To investigate expression of cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) and squamous cell carcinoma antigen (SCC-Ag) in cervical cancer patients with lung metastasis before treatment and their prognostic value. Methods The pretreatment serum expression levels of SCC-Ag and CYFRA21-1 of 72 cervical cancer patients with lung metastasis were measured. Survival rate analysis and Cox proportional hazard model were performed to evaluate the prognostic significance of two pretreatment variables. Results The media survival time (MST) of 72 patients was 14 months, and 38 (52.8 %) patients with pulmonary metastasis occurred in 1 year of treatment. The pretreatment serum SCC-Ag and CYFRA21-1 levels in the patients with tumor diameter over 4 cm or with squamous cell carcinoma were higher than those in the other patients (all P<0.05). The MST in the pretreatment serum CYFRA21-1 positive group (>3.3 mg/L) was higher than that in the negative group (13 months vs 19 months, P< 0.05), and the MST in the SCC-Ag positive group (>1.5 mg/L) was also higher than that in the negative group (14 months vs 21 months, P<0.05). The result of Cox regression analysis showed that the tumor diameter (OR = 11.6, P = 0.01), pretreatment serum SCC-Ag (OR= 4.2, P= 0.01) and CYFRA21-1 (OR= 8.2, P= 0.05) levels were independent prognostic factors of overall survival. Conclusion Pretreatment CYFRA 21-1 and SCC-Ag levels may be considered as useful prognostic indicators for cervical cancer patients with lung metastasis.

[Objective] To evaluate the biomechanical stability of lumbar intact specimen,anterior lumbar interbody fixation(ALIF)specimen,ALIF specimen fixed with pedicle screw and ALIF specimen fixed with translaminar facets screw.[Method]Each of eight adult fresh cadaver specimen of lumbarsacral segmcnts was analyzed in four states(groups):intact,L5S1 ALIF,L5S1 ALIF fixed with pedicle screw or fixed with translaminar facets screw,test and compare its range of motion(ROM)in flexion,extension,lateral bending and axial rotation.[Result]The ROM of ALIF specimen in extension was larger than that of intact specimen(P

Objective To evaluate the clinical effect of the free-hand cervical pedicle screw fixation in treatment of the upper cervical fracture and instability.Methods A retrospective review was performed on 15 patients with upper cervical fracture and instability treated with cervical pedicle screw fixation and fusion from September 2006 to January 2009.There were 11 males and 4 females,at average age of 41.2 years(range,18-60 years).Of all,there were five patients with atlas fracture and dislocation(including three simple anterior arch fractures and two Jefferson fractures),three with axis fracture and dislocation,one with dens fractures plus nonunion,two with C2,3 fracture and dislocation and four with atlantoaxial instability without fracture.The main clinical complaints included local neck pain and/or tetraplegia.Halo traction was recommended to restore the cervical sequence preoperatively in all patients.All 15 patients were treated by cervical pedicle screw-rods internal fixation and bone graft fusion.During the operation,the point and angle of the implanted pedicle screws were determined by preoperative X-ray and CT scan and the bony channel drilled with free-hand before implantation of the Summit or Vertex pedicle screws(22-26 mm long)and posterior interlaminar autologous or allogeneic bone fusion.Patients could get out of bed with neck collar at days 1-2 after operation.Results A total of 64 cervical pedicle screws were implanted in all 15 patients,with no vertebral artery injury,spinal cord injury or cerebrospinal fluid leakage.Postoperative X-ray and CT scan confirmed satisfactory internal fixation.The clinical symptoms were improved significantly.Fourteen patients were followed up for 12-36 months,which showed bony fusion,with no looseness or breakage of the screws.Neurologic impairment was improved in all patients,with no complications associated with the cervical pedicle screw.Conclusions Cervical pedicle screw internal fixation can reestablish the upper cervical vertebrae stability and help to recover the spinal cord and nerve function and hence is a reliable method for upper cervical fracture and/or instability.

BACKGROUND: There have been no effective means for clinical treatment of large regions of bone defects.Nano-hydroxyapatite/collagen(nHAC)composite would provide a new pathway for repair of bone defects owing to its similar structure to natural skeleton and better biocompatibility.OBJECTIVE: To investigate the role of nHAC composite co-cultured with bone marrow-derived mesenchymal stem cells(BMSCs)in repair of bone defects.METHODS: Following isolation and culture,human BMSCs were co-cultured with nHAC composite.Gross observation,histological analysis,and electron microscope observation were performed to analyze osteogenesis for repair of bone defects in the clinic.RESULTS AND CONCLUSION: Human nHAC could greatly proliferate in vitro.X-ray photography revealed that bone defects well healed after implantation of nHAC/BMSCs composite.These findings indicate that BMSCs exhibit osteogenic potential and nHAC is a satisfactory scaffold material for construction of tissue-engineered bone.

BACKGROUND:Several studies have demonstrated that stem cells can differentiate into vascular endothelial cells, and then further differentiate and form blood capillary. Based on this principle, autologous bone marrow mesenchyrnal stem cell (BMSC) transplantation promotes angiogenesis to treat ischemia in lower limb.OBJECTIVE: To evaluate the angiogenesis in rabbit ischemic limbs following autologous BMSC transplantation using high-frequency two-dimensional ultrasound detection in conjunction with Doppler color-flow imaging examination. DESIGN, TIME AND SEI-FING: A randomized, controlled, animal experiment was performed in the Third People's Hospital of Wuxi between March 2007 and April 2008.MATERIALS: Twenty-four New Zealand rabbits were randomized to a control group and a cell transplantation group, with 12 rabbits in each.METHODS: Ischemia in lower limbs was induced in all rabbits. One week following ischemia induction, the cell transplantation group was injected with 0.5 mL cell suspension, comprising 2×106 BrdU-labeled autologous BMSCs cultured in vitro, through multiple sites in the region of gastrocnemius muscle. Simultaneously, the control group received the same amount of physical saline in the same region.MAIN OUTCOME MEASURES: The initial segment of rabbit femoral artery and superficial femoral artery was subjected to high-frequency two-dimensional ultrasound and Doppler color-flow imaging examinations to measure femoral artery vascular internal diameter, blood flow peak velocity, and blood flow acceleration time. Ischemic muscular tissue was taken for immunohistochemical staining to detect transplanted cell distribution and for pathological examination of angiogenesis. RESULTS: Two weeks following autologous BMSC transplantation, high-frequency ultrasound results revealed that femoral artery internal diameter and blood flow peak velocity were greater, but blood flow acceleration time was shorter, in the cell transplantation group than in the control group (P<0.01). Immunohistochemical staining results demonstrated the presence of BrdU-positive cells. Pathological sections displayed that vascular density was significantly higher in the cell transplantation group than ih the control group. CONCLUSION: Autologous BMSC transplantation is a promising, simple, and effective method of treating ischemia in lower limbs owing to its promotion of angiogenesis. Meanwhile, high-frequency ultrasound detection of femoral artery is an effective, practical method to evaluate the clinical outcomes of autologous BMSC transplantation.

BACKGROUND: Longterm therapeutic effects of routine drug treatment, intervention or vascular bypass transplantation on lower extremity arterial occlusion are not ideal. During recent years, angiogenesis of stem cells possibly becones a new method to repair or rebuild an effective collateral circulation at infarct regions.OBJECTIVE: To verify the effect of autologous bone marrow mesenchymal stem cell transplantation on promoting angiogenesis in rabbit ischemic hind limbs.DESIGN, TIME AND SETTING: A randomized controlled animal study was performed in Jiangsu Institute of Schistosomiasis Control between August 2005 and November 2006. MATERIALS: Eight rabbits were used to prepare ischemic models of hind limbs, and then they were randomly divided into experimental group (n=4) and control group (n=4).METHODS: Bone marrow mesenchymal stem cells were isolated and cultured from New Zealand rabbits in the experimental group, and they were then marked 5-bromo-2-deoxyuridine (Brdu). Suspension of bone marrow mesenchymal stem cells was injected into the ischemic hind limbs in the experimental group, while the same volume of saline was injected into the controls. MAIN OUTCOME MEASURES: After two weeks, two-dimensional and color Doppler ultrasound detection was used on rabbit femoral artery to measure inner diameter of blood vessel, peak velocity and acceleration time of blood flow before and after transplantation. Muscle tissues were obtained from ischemic regions to observe distribution of transplant cells and state of angiogenesis using immunofluorescence staining and hematoxylin-eosin (HE) staining. RESULTS: Two weeks after transplantation, the inner diameter of femoral artery and the peak velocity of blood flow in the experimental group were higher than those in the control group (P < 0.01), but the acceleration time of blood flow was shorter than that in the control group (P < 0.01). Lmmunofluorescence staining showed that anti-Brdu-staining positive cells were found out in transplant part in the experimental group; while HE staining indicated that vessel density of ischemic region in the experimental group was higher than that in the control group. CONCLUSION: Bone marrow mesenchymal stem cells can promote angiogenesis, while autologous bone marrow mesenchymai stem cell transplantation will become a simple and effective method to treat lower limb ischemia.

BACKGROUND: Clinical observation demonstrates that accelerated fracture healing or lower limb heterotopic ossifications always occur in patients with paraplegia. It indicates that peripheral nervous system may play an important role in fracture healing process.OBJECTIVE: To observe bone histomorphometery parameter, callus formation and biochemical change during the process of fracture healing of unilateral lower limb denervated tibia.DESIGN: Self-control animal experiment.SETTING: Tianjin Hospital.MATERIALS: Totally 36 six-month-old healthy male Wistar rats, with mean body mass of 210 g, were used in this experiment.METHODS: This experiment was carried out at Animal Experimental Center of Tianjin Hospital from March 2001 to March 2004. Denervated tibia fracture model and innervated tibia fracture model were made in the same rat. Animals were executed under anaesthetic status at week 2 and week 4 after fracture. Bilateral tibias were chosen to take radiografts.Biomachamical strength was measured and non-decalcification sections were prepared to perform bone histomorphometery observation.MAIN OUTCOME MEASURES: ① Comparison of wet weight of bilateral tibias and callus of rats between two groups after fracture. ②X-ray plain film scoring. ③ Biomechanical testing of tibial samples. ④ Histomorphological observation of fracture healing RESULTS: ① Wet weight of bilateral tibia and callus of rats in denervated group was much higher than that in innervated group at weeks 2 and 4 after fracture [(0.94±0.15) vs (0.76±0.14) g, (1.06±0.26)vs (0.81±0.10) g,P ＜ 0.05]. ②In X-ray plain film scoring, callus formation was significantly increased in denervated group (P ＜ 0.01). ③In biomechanical testing of three-point bending of tibial sample, callus intensity was significantly lower at weeks 2 and 4 after fracture in denervated group than in innervated group[ (9.88±8.49)vs ( 16.62±13.38 ) N, ( 12.77±7.55 )vs (20.19±10.60) N,P ＜ 0.05]. ④Bone histomorphometery showed that compared with innervated group, mineralized bone trabecula width of denervated group was significantly reduced (P ＜ 0.05), osteoid width was increased , osteoclast index and bone absorption area were significantly increased (P ＜ 0.05), and there were no significant difference of fibroblast index and bone formation area between two groups; Compared with innervated group, mineralized deposition rate in the denervated group was significantly reduced (P ＜ 0.05), the mature time of osteoid was elongated (P ＜ 0.05).CONCLUSION: Peripheral nervous system may play an important role during early and middle period of fracture healing. Intact innervation is essential for normal fracture healing.

10.3969/j.issn.2095-4344.2013.23.006

Objective To study the effects of peripheral nervous system on early and middle periods of fracture healing. Methods Denervated tibia fracture model and innervated tibia fracture model were made at the same rat. The animals were executed at day 15 and day 30 after operation respectively. Callus sizes were evaluated by radiograph. The mechanical properties of calluses were recorded in a three point bending test. The callus microstructures were measured by bone histomorphometry.Results Radiograph showed an increased callus formation in the denervated group both on day 15 and day 30 after operation (P0.05). Compared with the innervated groups, 30 days dynamic parameters indicated that mineral appositional rates of the denervated sides significantly decreased (P