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Objective To evaluate the expression of human vascular endothelial cell growth factors 165 (hVEGF165) gene transfected into fibroblasts by recombinant adenovirus and study the repairing effect of this cells on radiated skin ulcer in rats.Methods The recombinant adenovirus with hVEGF165 was established and transfected to rat primary fibroblasts, and its expression of hVEGF165 in fibroblasts was identified with real-time PCR, immunocytochemistry and Western blot.Twenty four clean grade SD rats of were irradiated locally with 50 Gy γ rays to generate an animal model of radiation skin injury.The hVEGF165-transfected cells were injected to the irradiated site under rat skin 7 d post-irradiation.The therapeutic effects on the irradiated skin wound were evaluated through general observation as well as histological staining of HE.The expression of hVEGF in the irradiated skin tissue with fibroblasts injection was analyzed by Real-time PCR.Results The hVEGF165 gene was overexpressed in the transfected cells and approached to 88 373-fold bigger compared to controls transfected with blank vectors, and an extensive expression of VEGF in the cytoplasm of transfected cells was observed by immunohistochemistry.VEGF protein with the relative molecular mass of 23 000 was also detected in cell lysate by Western blot.The local skin ulcers in rats occurred about two weeks after irradiation.In the hVEGF165-transfected group, the average area of radiation-injured skin was 40.2 mm2, about 57％ less than that of the control group transfected with blank vectors so that the healing time was shorten by 6 days.The relative concentration of hVEGF mRNA in the skin tissue of rats injected with hVEGF165-transfected cells were 5.15-fold and 4.15-fold bigger compared to that of controls (t =3.385,3.220, P ＜ 0.05) at 3 and 7 d after administration.Conclusions The primary fibroblasts transfected with hVEGF165 gene could efficiently release VEGF to the irradiated skin tissue and promote the recovery of irradiation skin ulcers by shortening the healing time and thus enhanced the therapeutic effect on skin wounds.
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BACKGROUND:It is important to prepare a mal eable putty to repair irregular bone defects because the preformed bone substitute material cannot suit to bone defects. OBJECTIVE:To prepare mal eable demineralized bone matrix/hyaluronic acid putty and to screen out the optimal composite ratio, as wel as to evaluate its cellcompatibility. METHODS:Demineralized bone matrix was prepared from the cortical bone of healthy donors. The hyaluronic acid was dissolved at concentrations of 0.75%, 1.5%, 3%, 4.5%, and the viscosity of them was measured. Then 450 mg demineralized bone matrix was compounded with 1 mL hyaluronic acid solution to prepare the demineralized bone matrix/hyaluronic acid putty, and the optimal ratio of demineralized bone matrix/hyaluronic acid was screened by the disintegrated time of the putty at 37 ℃. L-929 mouse fibroblasts were cultured in the leaching liquor of demineralized bone matrix/hyaluronic acid, and the cytotoxicity was tested by cellcount kit-8 assay at days 1, 4 and 7. RESULTS AND CONCLUSION:With the increase of hyaluronic acid concentration, the viscosity of hyaluronic acid solution was increased;the demineralized bone matrix/hyaluronic acid putty was strengthened and the disintegrated time was prolonged gradual y. When the ratio of demineralized bone matrix/hyaluronic acid was 15/1, demineralized bone matrix/hyaluronic acid was molded easily, and the disintegrated time was 8 hours in 7 ℃ PBS. The results of cytotoxicity showed that cellproliferation rates were 93.72%, 101.65%and 97.68%at days 1, 4 and 7 respectively, while the cytotoxicity was in grade 0 or 1. These findings indicate that demineralized bone matrix/hyaluronic acid putty at a compound ratio of 15:1 can be molded easily and difficult to disintegrate, with low cytotoxicity.
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Objective To explore the way to reduce the absorption of irrigating fluid during PCNL. Methods The amount of absorbed fluid during PCNL in 20 cases (13 males and 7 females)was monitored by ethanol method. The average age was 40 years old. The maximum diameter of calculi by average was 25 mm. Heart rate and mean arterial pressure were monitored during operation.Haemoglobin concentration, serum Na+, K+, Cl-, carbon dioxide-combining power and serum creatinine were measured before and after operation. The amount of irrigating fluid, the duration of operation, and the intrapelvic pressure were recorded. Results The absorbed volume of irrigating fluid in 20 cases was from 50. 2 to 685.0 ml. There was no significant difference in heart rate, mean arterial pressure, serum Na+ , K+ , Cl- and serum creatinine between pre-operation and post-operation(P>0.05), but the postoperative haemoglobin concentration (130.4±16.3 g/L) and carbon dioxide-combining power (24.1±3.2 mmol/L) were lower than that before operation( 142.6±15.6 g/L,26.4±2.0 mmol/L), the differences were significant (P<0. 05). The mean volume of absorbed irrigating fluid in patients with the cumutative time of the intrapelvic pressure higher than 30 mm Hg >10 min,the duration of operation >1 h, or the amount of irrigating fluid >10000 ml was 381. 1, 301.6,261.6 ml respectively, which was higher than that in the other cases (142.9, 136.4, 130.2 mi), the differences were significant (P<0.05). Conclusions The ethanol method is simple, convinent,safe, valid, and is suitable for patients with compromised cardiorespiratory or renal function, who are more likely to develop volume overload because of fluid absorption.
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BACKGROUND: Human allogenic acellular dermal matrix, as a kind of permanent dermal scaffold, has widely used in the fields of burn wound reparation and aesthetic medicine. However, it is limited due to insufficient resources. OBJECTIVE: To prepare porcine acellular dermal matrix (PADM) dermal matrix, in addition, to estimate its in vitro biocompatibility. DESIGN, TIME AND SETTING: An in vitro cytology contrast experiment. The Experiment was performed at the laboratory of Biomaterials and Pharmacy Technology Institute, China Institute for Radiation Protection between August 2007 and June 2008. MATERIALS: The experiment pigs were supplied by experimental animal center of China Institute for Radiation Protection. Human fibroblasts were obtained from prepuce tissues of healthy children who underwent circumcision at the Shanxi Provincial General Hospital, Chinese People's Armed Police Forces. METHODS: The PADM was prepared from porcine skin by removing epidermis with a hypertonic salt solution and excluding cellular components in dermis with sodium dodecyl sulfate, and trypsin in hypersonic conditions. Human fibroblasts were cultured in vitro, and the biocompatibility of PADM was estimated with MTT method and contact method. MAIN OUTCOME MEASURES: ①Histological morphology of PADM. ②In vitro biocompatibility of PADM. RESULTS: The prepared PADM was a kind of matrix with normal structure and organization of collagen without epidermis and any cellular components in the dermis. The extraction of the porcine acellular dermal matrix had no effect on proliferation of the cultured human fibroblast. The cultured human fibroblasts could attach and proliferate on PADM. CONCLUSION: The PADM effectively removed epidermis and all cellular components with excellent biocompatibility can be obtained by this preparation method.
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Objective To compare perioperative parameters, as well as the oncological and func-tional results, for laparoscopic radical prostatectomy (LRP) performed via the posterior bladder and anterior bladder approaches. Methods The recorded pre-, peri-, and postoperative parameters and complications, and evaluated the oncological and functional results were collected and compared be-tween the posterior bladder approach (n=25) and the anterior bladder approach (n=34). Results There were no significant differences regarding the preoperative characteristics of the two groups. The mean blood loss, complications, positive surgical margins, and continence showed no significant differences between the 2 groups at 3 and 6 months postoperatively. The mean operation time was sig-nificantly shorter in anterior bladder approach group (174.2±58. 0 min) than in posterior bladder ap-proach group (224. 8±66.7 rain), (P<0. 01). Also, the postoperative recovery time until discharge was 5.9 d in anterior bladder approach group, which was significantly shorter than in posterior bladder approach group (7.5 d) (P<0.05). Conclusion The anterior bladder approach yields shorter oper-ation time and postoperative recovery period than posterior bladder approach for LRP.
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BACKGROUND:The materials for internal fixation of bone allografts have been used in the clinic.However,they are only used in the regions bearing little stress because of low strength.The focus of current studies is how to enhance the fixation strength of the materials to expand application range.OBJECTIVE:To compare the strength difference of cortical bone allografts among different fixation modes and to investigate the possible mechanisms of action.DESIGN,TIME AND SETTING:An in vitro biomechanical experiment was performed at the Laboratory of Biomechanics,Nanhua University between October 2005 and March 2006.MATERIALS:Twenty-seven pieces of cadaveric femurs were included in this study.A total of 45 cortical bone allografts with a size of 110 mm×10 mm×3 mm and 90 bone screws were also used.METHODS:Twenty-seven femurs were made into simulated fracture models and randomized to 3 groups,with 9 models per group:A,B,and C.In the group A,the models were fixed with two cortical bone all6grafts; the models from the groups B and C were fixed with two bone allografts plus 5 bone screws and one bone allograft plus 5 bone screws accordingly.MAIN OUTCOME MEASURES:Biomechanical tests were performed in the above-mentioned 3 groups to measure compressive,bending and torsional stiffness as well as the maximum loads.RESULTS:Different fixation models displayed different mechanical characteristics.The group A exhibited similar compressive stiffness compared to the group B,but the level was significantly higher compared to the group C (P ＜ 0.05).The other two stiffness parameters including bending and torsion were significantly greater in the group A than in the groups B and C (P ＜ 0.05).The maximum loads of compression,bending,and torsion were significantly greater in the group A compared to the group B (P ＜ 0.05) and group C (P ＜ 0.01).CONCLUSION:The strength of bone allograft is highly related to fixation mode. The two bone allografts showed greater strength and stiffness than struts fixed with bone screws,which meet the clinical requirements.
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BACKGROUND:The need for bone graft and its substitutes has dramatically increased during the past decade. Either bio-derived graft materials or synthetic materials cannot satisfy this need. Study of composite bone graft has become a focused field.OBJECTIVE: To develop a novel porous poly (lactic-acid) (PLA)/bone matrix gelatin (BMG) bioactive composite material by means of supercritical carbon dioxide fluid technique (SC-CO2) and evaluate the bone forming potential in vitro.DESIGN: A comparative study and observation.SETTING: Research Center of Tissue Engineering, Southern Medical University; Institute of Biomaterials and Pharmaceutical Technique, China Institute for Radiation Protection.MATERTALS: Mouse osteoblast-like MC3T3-E1 cells were obtained from RIKEN Cell Bank in Japan. PLA was supplied by the Institute of Bio-technique of Jinan University. Alkaline phosphatase (ALP) kit was the product of Nanjing Jiancheng Bio-engineering Institute. MC3T3-E1 cells were cultured in Dulbecco's modified eagle medium (DMEM) (Gibco Laboratories, USA) supplemented with 10% fetal bovine serum (FBS, Si Ji Qing, China), 100 mg/L penicillin and 100 U/L streptomycin in a 37℃ humidified atmosphere. The cells were passaged with 0.25% trypsin (Gibco Laboratories, USA).METHODS: The experiment was carried out in the Research Center of Tissue Engineering, Southern Medical University from October 2005 to July 2006. The porous PLA/BMG composite biomaterials and PLA were prepared with SC-CO2 technique, and then macroscopic and microscopic observations were performed. The MC3T3-E1 cells were co-cultured with PLA and PLA/BMG in vitro, and DMEM was taken as the blank control group. Each well was pictured with digital camera.The percentage of the stained area, standing for the calcification deposition, was determined with an image processing and analysis software. The ALP activity and calcium content were determined with the method of ultrasonic cell lysis.MArN OUTCOME MEASURES: ① Macroscopic and microscopic observation of PLA/BMG; ③ Quantitative measurement of the calcification area; ② ALP activity and calcium content.RESULTS: ① Macroscopic and microscopic observation of PLA/BMG: The PLA/BMG showed good homological porosity with the size of 50-150 μm and connectivity: There were many holes with the size of 5-10 μm in the PLA/BMG walls. The PLA and BMG were mixed uniformly. ② Calcification areas: The percents of calcification area were significantly different among the PLA/BMG group, PLA group and blank control group [(42.98±4.44)%, (9.55±1.94)%, (0.86±0.41)%, P ＜ 0.01]. ③ Results of calcium content and ALP activity: The ALP activities were significantly different among the PLA/BMG group, PLA group and blank control group [(5 427.58±1173.57), (1 060.54±500.27),(40.01±24.50) nkat/g, P ＜ 0.05-0.01]; The calcium content in the PLA/BMG group was higher than those in the PLA group and blank control group [(3.51±1.64), (1.04±0.21), 0.70±0.24] mmol/g, P ＜ 0.01].CONCLUSTON: The PLA/BMG prepared by means of SC-CO2 has a good osteoinductive activity and it is worth studying further as bone biomaterial and bone tissue engineered scaffold.
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BACKGROUND: To discuss the feasibility of allogeneic freeze-drying radiation sterilization bone sheet applying in the prevention of post-laminectomy adhesion as an ideal biological material for filling and repairing bone defect. OBJECTIVE: To observe the preventive effect of allogeneic freeze-drying radiation sterilization bone sheet on the postlaminectomy adhesion and restenosis.DESIGN: Follow-up survey on cases.SETTINGS: Department of Orthopedics, Union Hospital, Tongji Medical School of Huazhong University of Science and Technology; Shanxi Medical Tissues of China Institute for Radiation Protection PARTICIPANTS: From March 2003 to June 2005, 58 patients with segmental lumbar spinal stenosis (LSS) were selected from Department of Orthopedics, Union Hospital, Tongji Medical School of Huazhong University of Science and Technology, including 34 males and 24 females, aged 30-78 years, including 25 cases of simple LSS and 33 combined LSS; and including 36 cases in L4-5 and 33 cases in L5, S1 segments. All the patients were similar in age, gender and healthy conditions.METHODS: The segmental whole laminectomies were performed in 58 patients with prolapse of lumbar intervertebral or LSS, and allogeneic freeze-drying radiation sterilization bone sheet in "H" shape was used to cover the vertebral laminae. According to the follow-up standard of lumbar spine operation recommended by the Orthopaedics Branch of Chinese Medical Association, all patients were followed up to evaluate their clinical symptoms, absorption of implanted bone as well as CT and MRI presentations.MAIN OUTCOME MEASURES: Improvements of clinical symptoms;Absorption of bone sheet in lumbar spinal canal.RESULTS: Totally 58 LSS patients were involved in the result analysis.In postoperative 0.5-year follow-up period, 17 of 21 patients showed excellent curative effects while other 4 patients showed fine effects. In postoperative 1-year follow-up period for 23 patients, CT and MRI results demonstrated that the spinal canal had been extended obviously. There was no tilt or displacement of the femoral sheet or compression of the spinal cord. As for 14 patients who were followed up for 1.5 years, CT results displayed that there was no rejective reaction observed in this study. The edgeof the allograft was inosculated with connective lamina of vertebra, and the shape of lumber spinal was good.CONCLUSION: Allogeneic freeze-drying radiation sterilization bone sheet is an ideal dressing material for epidural laminoplasty. The imaging results of patients in postoperative 1.5-year follow-up indicate that it can effectively reduce the post-laminectomy adhesion formation and prevent recurrence of post-laminectomy spinal restenosis, so as to apply on the segmental vertebral plate dressing.
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Objective To investigate the effect of minimally invasive percutaneous nephrolithotomy(MPCNL) in the management of renal or ureteral calculi.Methods MPCNL was performed in 52 patients with renal or ureteral calculi under the localization of C-arm fluoroscopy and/or B-ultrasonography.Results Among the 52 patients,a conversion to open surgery was needed in 1 patient because of perforation of the renal pelvis.The stones were completely extracted on one session in 33 patients,and by a re-operation of MPCNL through the fistulization tube 1 week later in 15 patients.The total stone-free rate was 92.3%.The operation time was 1.5~4 h(mean, 2.5 h).No blood transfusion was needed.Conclusions Minimally invasive percutaneous nephrolithotomy is a safe and effective procedure,especially suitable for basic hospitals.
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Objective To evaluate the treatment of ureteral stones with pneumatic lithotripter under ureterscopy and the prevention of complications. Methords 43 cases of ureteral stones that had been treated with pneumatic lithotripter under ureteroscopy was reviewed. Results 93.0%(40/43)of the stones were fragmented on one session,93.0%(40/43)of the stones were expelled within 7 days afer the procedure.No complications occurred. Conclusions Treatment of ureteral stones with pneumatic lithotripter under ureterscopy is safe and effecive.
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Ojective To study the probability of laparoscopic adrenalectomy in the treatment of adrenal benign tumor. Methods Laparoscopic adrenalectomy were used to treat pheochromocytoma and primary aldosteronism. Results Average operation time was 200 min and average bleeding was 110 ml. The patients began to walk two days after operation. Hyperension and low blood potassium level syndrom disappeared gradually. Conclusions Laparoscopic Adrenalectomy has the advantage of minimal invasion, faster recover from operation, shorter hospitolized days and higher quarlity of life after operation for the patients.
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Objective To study the effects of various doses of ionizing radiation on the osteoinductive activity of recombinant human bone morphogenetic protein 2 (rhBMP-2) and the role of collagen carrier. Methods BMP complex was prepared with rhBMP-2 and collagen sponge as a carrier. The osteoinductive activity of rhBMP-2 was evaluated by heterotopic bone formation. According to the conditions of gamma irradiation, the experiments were divided into 4 groups: (Ⅰ) non-irradiated complex as control; (Ⅱ) irradiated complex with 15, 20, 25 or 50 kGy; (Ⅲ) irradiated carrier: collagen sponge was irradiated with 50 kGy and then mixed with non-irradiated rhBMP-2; (Ⅳ) irradiated BMP: only rhBMP-2 was irradiated with 25 or 50 kGy and then mixed with non-irradiated collagen sponge. The BMP complexes were implanted into thigh muscle pouches in 34 Wistar rats, respectively. All collagen mass in muscle pouches were procured two or four weeks after implantation and examined macroscopically, radiographically and histologically. Quantitative analyses of heterotopic bone formation were evaluated by histomorphometry. Results Two weeks after implantation, collagen mass procured from muscle of irradiated complexes with 15, 20, 25 kGy are almost the same with that of control in size, shape and new bone formation, which are composed with richly vascularized connective tissue and immatured woven bone, but only the quantity of new bone in the group of 25 kGy reduced significantly(P