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Objective:To access the efficacy of external fixation combined with Prontosan management for open fractures complicated with multidrug-resistant bacterial infection.Methods:A retrospective analysis was conducted of the data of 22 patients with open fracture complicated by multidrug-resistant bacterial infection who had been admitted to Department of Orthopedic Trauma and Microsurgery, Zhongnan Hospital of Wuhan University from January 2015 to January 2020. According to whether the Prontosan management was used or not, the patients were divided into 2 groups.The Protosan group [9 males and 3 females with an age of (44.6±13.1) years] were subjected to external fixation, vacuum sealing drainage(VSD) or conventional dressing changes, and at the same time Protosan management to flush the wound or Prontosan gel to change dressings.The control group[6 males and 4 females with an age of (45.1±11.7) years] were subjected to external fixation plus VSD or conventional dressing changes. Skin flaps or skin grafts were used to repair the wound immediately after the wound infection was controlled in both groups. The time for negative culture of the bacteria on the wound surface, number of debridement, survival of the skinflaps or grafts, and fracture union were recorded and compared between the 2 groups.Results:There was no significant difference in the preoperative general data between the 2 groups which were comparable( P>0.05).All patients were followed up for 10 to 24 months (mean, 14.5 months).In the Prontosan group, the number of debridement was 2.0 (2.0, 3.0) times, significantly fewer than that in the control group [4.0 (3.0, 4.0) times]; the time for negative bacterial culture (8.3±2.2) d, significantly shorter than that in the control group [(14.2±3.1) d]; the fracture union time (5.5±1.1) months, significantly shorter than that in the control group [(6.5 ±1.1) months]; the Samantha X-ray score at 6 months after operation 6.0 (5.0,6.0) points, significantly higher than that in the control group [5.2(4.5,5.5) points] (all P<0.05). Skin flaps or grafts survived in all the patients without any nonunion or chronic osteomyelitis. Conclusion:In the external fixation of open fractures complicated with multidrug-resistant bacterial infection, combination with Prontosan management can effectively control infection and promote granulation, early wound healing and fracture union.
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Objective:To evaluate the therapeutic effect of exposed bone cement in treatment of infectious bone and soft tissue defect by comparison with routine bone cement therapy.Methods:A retrospective analysis was carried out in 27 patients who had been treated from January 2016 to January 2020. Of the 27 patients, 12 were treated by exposed bone cement filling for bone defect at the first stage, followed by flap and bone grafting at the second stage. Other 15 patients were treated by routine bone cement filling and flap repair at the first stage, followed by bone grafting at the second stage. Regular dressing change was carried out after surgery. All patients entered follow-up by out-patient review for wound condition and X-ray. Infection rate of bone and soft tissue, time of bone union, flap survive rate and complication were compared between the 2 groups.Results:The follow-up lased for 9-24(16.5±3.9 ) months. The bone defects were all healed. The treatment time of bone defects in the group of exposed bone cement was 25-34(28.5±2.8) weeks. The treatment time of bone defect in the routine cement group was 25-36(29.6±3.4 )weeks. There was no statistical difference between the 2 groups( P<0.05). Two cases in each group had failed in infection control after bone cement implantation. With further debridement, cleaning and other treatment, the infection was under control. All flaps in the 2 groups survived. In the group of exposed bone cement, there were 3 flaps splitting, 2 hemorrhage(effusion) and 1 partial flap necrosis, In the routine bone cement group, there were 4 wound dehiscence, 8 hemorrhage(effusion) and 3 partial flaps necrosis. There was no significant difference in flap complications between the 2 groups( P>0.05). The healing of bone defect was evaluated by Samantha X-ray score, the scores of the 2 groups were 5.41±0.67 and 5.40±0.63, respectively, with no statistical significance. The Paley's approach was used to grade the bone healing and the function of adjacent joints. Paley bone defect healing evaluation results weve all excellent. Joint function assessment were as follow: in the group of exposed bone cement, 6 cases were excellent and 3 were good; in routine bone cement group: 6 cases were in excellent and 5 in good. There was no significant statistical difference. Conclusion:Compared with a routine bone cement treatment, the exposed bone cement in the treatment of infectious bone defects saw a fewer flap splitting and fewer hemorrhage/effusion, without an increase in bone and soft tissue infection. This procedure could be considered for further trials in the treatment of a composite defects of infected bone and soft tissue.
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Objective:To analyze the causes of SARS-CoV-2 nosocomial infection among healthcare workers (HCWs) and explore the effective precaution strategies in Emergency Center.Methods:The data of SARS-CoV-2 infected HCWs from January 5 to March 2, 2020 were retrospectively analyzed and compared under different conditions in Emergency Center of Zhongnan Hospital of Wuhan University.Results:Totally 13 SARS-CoV-2 infected HCWs (12 confirmed cases and 1 suspected case) were included in this study. The overall infection rate was 17.8% (13/73). The infection rates in outpatient/rescue room, isolation observation room and isolationin patient ward were 11.8% (4/34), 20.0% (3/15), 25% (6/24), respectively. The infection rate of physician was 13.0% (3/23), and the infection rate of nurse was 20.0% (10/50). All the infected HCWs had the definite exposure with confirmed or suspected COVID-19 patients. One asymptomatic cases were identified by laboratory findings of SARS-CoV-2 infection screening. There was no new confirmed SARS-CoV-2 infected HCWs after February 5, 2020. All the infected HCWs were cured.Conclusions:Under the epidemic of COVID-19, HCWs of Emergency Center have a high risk of occupational exposure and infection, especially for staffs working in COVID-19 isolation units. Scientific prevention and control management can effectively reduce the risk of SARS-CoV-2 infections and ensure the occupational safety for HCWs in Emergency Center.
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Objective:To summarize the preliminary experience in ward management, medical protection, standardised diagnosis and treatment procedures in trauma microsurgery during the outbreak of COVID-19.Methods:Taking an example from the Department of Trauma and Microsurgery at Zhongnan Hospital of Wuhan University, the orthopedic patients and medical staff with COVID-19 admitted from Decemberm 31, 2019 to March 1, 2020, in-cluding clinical diagnosis and confirmed cases, were analyzed retrospectively. General information, including age, gen- der, basic diseases, contact history, symptoms, lung CT and prognosis, were collected and analysed preliminarily. On January 20, 2020, the COVID-19 outbreak was confirmed as "human to human transmission". COVID-19 infection of patients and medical staff in the wards were analysed, through the update of protection awareness and control measures. Department management, medical protection and standardized control procedures of trauma microsurgery were explored.Results:Five cases with clinical diagnosis or confirmed COVID-19 were included. One was inpatient and the rest 4 were medical staff, aged 25-81 years, 3 with confirmed and 2 with clinical diagnosis of COVID-19. After the treatment by specialists from Department of Infectious Disease and Department of Respiratory Disease, 4 of infected persons were cured and 1 died. Since January 20, 2020, when it was clear that the virus transmitted to people, there was no new case of infection among the medical staff and inpatients after the multidisciplinary collaboration in the ward prevention and control procedures were standardized and took in action.Conclusion:The spread of the COVID-19 can be effectively controlled by standardised diagnosis and treatment procedurs in the word of trauma microsurgery.
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To summarize the application of enhanced recovery after surgery (ERAS) principles in treating long bone defect with free fibula graft (FVFG). Methods From January, 2012 to January, 2017, ERAS principles were applied in 26 cases of long bone defect treating with vascularized fibula flap graft, via a series of com-prehensive measures, including strengthening psychological nursing, nutrition support and pain management, optimiz-ing operation plan, and early scientific functional exercise. Surgical duration, hospital stay time, satisfaction of pa-tients, postoperative visual analogue scale (VAS) score, bone defect healing time, and Enneking score were recorded through regular outpatient follow-up after discharge. Results The average length of surgical duration and hospital stay time was(3.2±0.5) h and (10.2±1.2) d, respectively. Discharged satisfaction was greater than 95%. Postoperative VAS score was less than 3. During the follow-up period of 1.6-6.0 years, 26 fibular flap survived, and all the bone defect were healed, with an average healing time of (5.5±0.6) months.Followed-up at 1.5 years after the operation, the upper limb function of 7 patients increased by 80.1%, and the lower limb function of 19 patients increased by 82.5%. Conclusion The application of ERAS in treating long bone defect with FVFG can obtain satisfactory limb function, alleviate patients’pain, shorten the duration of hospitalization, promote the rehabilitation and satisfaction of patients.
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Objective To compare internal fixation with hallow compression screws combined vascularized bone graft(observation group) with only three hallow compression screws(control group) in young patients' Garden III and IV femoral neck fractures. Methods The patients with femoral neck fracture were treated from January, 2004 to December, 2013 were retrospectively reviewed. A total of 417 displaced femoral neck fractures in young and mid-dle-aged patients were long term followed-up. One hundred and thirty-seven patients were underwent open reduction and internal fixation with 3 hallow compression screws combined with a greater trochanter bone graft supported by the profound branch of medial circumflex femoral artery;280 patients were treated by closed reduction with 3 hallow com-pression screws. Results Patients had been followed-up for 5-12 years. At the last follow-up point, the Harris score of flap in observation group(93.68±5.12) were higher than that in control group(92.53±6.12), while it was no sta-tistical difference(P>0.05). It was 0.7％of nonunion incidence rate in the observation group, and incidence of avascular necrosis of femoral head was 6.6％, and incidence of femoral neck shortening was 8.8％. In the control group, inci-dence of avascular necrosis of femoral head was 14.6％, nonunion incidence rate was 4.6％, and incidence of femoral neck shortening was 22.5％. The differences between two groups was statistically significance( P<0.05). Conclusion The open reduction and internal fixation which is hallow compression screws in combination with a greater trochanter bone graft supported by the profound branch of medial circumflex femoral artery is an optimal treatment for young adults with Garden III and IV femoral neck fractures.
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Objective To explore the effect of the use of flap transplantation combined with Masquelet tech-nique in the repair of long bone accompanied with soft tissue defect. Methods The retrospective study includes 16 cases of bone defects over 6.0 cm combined with soft tissue defect from March,2013 to March,2016,13 males and 3 females, of which the ages range from 16 to 65 years. The length of bone defect ranged from 6.0 to 12.0 cm, with an average of 8.5 cm,while the wound defect ranged from 5.2 cm×3.5 cm to 16.0 cm×7.5 cm. There were 8 cases out of 16 involve an infection:3 cases of Staphylococcus aureus(including 1 MRSA),2 cases of Staphylococcus epidermidis, 2 cases of Enterobacter cloacae, and 1 case of Acinetobacter baumannii. The 1 stage surgery in all patients admitted to hospital after complete debridement and external fixation, the clean wounds with bone defect received antibiotic-impregnated bone cement filling operation and a flap transplantation or transposition directly after the debridement, but the infected wounds received vacuum sealing drainage treatment firstly, associated with adequate use of antibi-otics for 1-2 weeks and then the bone cement filling and flap transplantation with infection totally controlled.After 8-12 weeks, we conducted the secondary internal fixation surgery replacing antibiotic-impregnated bone cement with autogenic cancellous bone, vancomycin artificial bone as well as rhBMP-2. All the cases were followed for 6 to 18 months. Results All patients with primary surgery are effectively controlled after 1-4 weeks of anti-infection treat-ment exclusive of the case with MRSA.As the condition of the patient with MRSA relapse,we changed to convention-al treatment: placed a continuous irrigation and suction equipment instead of the bone cement filling, the wound healed completely without fistula formation of osteomyelitis in 6 months after the treatment of Ilizarov technique. All transplantation and transposition flaps survived. As for those who received a secondary bone graft operation, all achieved a bony union in a period of 4-6 months. Conclusion The combination of flap transplantation and Masquelet technique is an effective method to repair limb long bone and soft tissue defect currently.
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Objective To summarize the clinical experience of treating long bone defect with vascularized fibular graft.Methods From January,2008 to January,2015,31 cases of long bone defect were treated with vascularized fibula composite or not composite tissue flap graft.The length of transplanted fibula was 9-20 cm,and the flap area was 5 cm×3 cm to 21 cm×14 cm.All patients were followed up regularly.Limb function was assessed 12 months after surgery.Results Thirty-one cases of vascularized fibular flap survived after surgery.Thirty patients were followed up for 1.5 to 6 years (average,2.5 years).One patient was lost to follow-up.The bone defects of patients followed up were healed.There was one case fracture occurred for trauma,was treated with plaster cast for 6 months and healed.The transplanted fibular thickened for 1.3 to 2.5 years(average,1.6 years).Conclusion Vascularized fibular graft can reconstruct long bone defect for single use and shorten the duration of treatment with a good limb function.For cases combined soft tissue defect,vascularized fibula composite tissue flap can be applied to repair at the meantime.
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BACKGROUND:Bioactive glass, a multi-phase composite material, has good biological activity, bone conductivity and biocompatibility, but as a bone repair material it cannot be completely degraded, and has low mechanical strength that is insufficient. OBJECTIVE:To design a kind of bioactive glasses/chitosan composite scaffold, and to investigate its physicochemical properties and cellcompatibility. METHODS:Hydrochloric acid solution containing 2.0%chitosan was mixed withβ-glycerophosphate at a radio of 7:1 to prepare chitosan solution. Bioactive glasses of 0.5, 1.0, 1.5 g were added into the prepared chitosan solution, and the mass ratios of chitosan and bioactive glass were 2:1, 1:1, and 1:1.5 respectively. The composite materials were immersed and mineralized in simulated body fluid for 7 days. RESULTS AND CONCLUSION:Scanning electron microscopy showed that the composite scaffold had an interconnected porous structure with the porosity of 89%and the pore size of 100-300μm;bioactive glasses dispersed in a needle shape between the chitosan scaffolds, arranged evenly, and were ful y wrapped tightly by the scaffolds. With the increase in mass of bioactive glass, the porosity of the composites decreased, but the fracture strength gradual y increased. There was a positive correlation between the composite porosity and fracture strength. X-ray diffraction and Fourier transform infrared spectroscopy confirmed that the composite scaffold appeared to have no changes in the nature of single materials, and differential scanning calorimetry analysis showed no mass loss at normal body temperature. After 3 days of mineralization, hydroxyapatite forming on the material surface gradual y grew up as a vil ous shape, and also significantly increased in number. After 7 days of mineralization, hydroxyapatite changed from a vil ous shape to a needle shape, the amount of hydroxyapatite was increased further, and many mineralized products were in a spherical shape.
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ObjectiveTo investigate the feasibility of hTGF-β1 transfected bone mrrow mesenchymal stem cell (BMSCs) combined with calcium alginate gel in three dimensional condition to construct tissue engineering cartilage.MethodsRats BMSCs were obtained and cultured by whole bone marrow method,and then the third-generation cells were seeded into cell culture plate,and were divided into 3 groups:AdhTGF-β1 transfected group, Ad-EGFP transfected group and control group. The control group was added in common medium without any treatment while the other 2 groups were respectively added in serum-free medium containing Ad-hTGF-β1 or that containing Ad-EGFP.Seven days later,real-time fluorescent quantitation PCR and Western blot were employed for detecting the expression of TGF-β1.Then,the BMSCs which successfully transfected by Ad-hTGF-β1,were continually cultured in vitro.Andthe confound of cells-calcium alginate gel,the cell density was 1.0 × l07 per ml,were prepared and cultuered in constant temperature incubator.Ten days later,examine the morphous and proliferation of cell.Last,paraffin slice of the cell-gel confound was stained by HE,toluidine blue and Masson staining,while immunohistochemical for the secretion of collagen Ⅱ.ResultsSeven days after the transfection, real-time fluorescent quantitation PCR revealed that the average relative expression of TGF-β1 was:Ad-hTGF-β1 group 0.863,and Ad-EGFP group 0.183, the control group 0.180, and the expression difference of TGF-β1 was statistically diffence(P ＜0.05). Western blot proved strong TGF-β1 expression in Ad-hTGF-β1 group while it was detected a little in the other two groups. Globose cells were observed through inverted microscope in the calcium alginate gel.MTT proved the amount of cells were not statistically diffence (P ＞ 0.05) at different time point.HE staining proved amount cartilage lacuna formation in the gel, while the secretion of cartilage matrix were proved by toluidine blue and Masson,and immunohistochemical proved the expression of collagen Ⅱ.Conclusion BMSC trnsfected by hTGF-β1 could be successfully induced to chondrocyte, as the cells morphous maintained.This three dimensional condition could preferably mimicry cell growth pattern as in vivo.
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Objective To investigate the choice of methods and time on the treatment of Gustilo type Ⅲ B and type ⅢC open tibia fractures by bone fixation and tissue flap repairing.Methods The clinic data of 136 cases of Gustilo Ⅲ B and Ⅲ C open tibia fractures were retrospectively studied.There were 102 males and 34 females,with average age of 34 years(range 14 to 68 years).Ninety-eight cases were classified as Gustilo type Ⅲ B and 38 cases were type Ⅲ C in degree.In all cases,one hundred and thirteen were treated with onestage external fixation,ninteen cases were treated with secondary bone fixation.Sixty-seven cases of all wounds were repaired by one-stage vascular pedicle skin flap.Seven wounds were repaired by one-stage free flaps with vascular anastomosis.Sixty-two cases were secondary repaired by different flaps after defect tissue under VSD (vacuum-sealing-drainage) treatment by 1 to several weeks,which contains 9 free skin graft,eleven muscle flaps based on posterior tibial artery perforator,thirteen flaps based on fibial artery perforator,fourteen gastrocnemius falps and 15 cross-leg flaps.Results Wound of all cases were healed wholly.Primary union occurred in 121 cases,twelve,cases healed after bone grafting for segmental bone defect.Three cases with delayed union healed after reoperation for infection that caused osteomyelitis and sinus tract.The period of bone healing was form 5 to 12 months.Conclusion The treatment of Gustilo Ⅲ B and Ⅲ C open tibia fractures by onestage or secondary bone fixation and tissue flap repairing get their advantages and disadvantages,but one-stage bone fixation and tissue flap repairing was better where appropriate.
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ObjectiveTo evaluate the physicochemical properties and bicompatibility of carbon-nanotubes/hydroxypatite/chitosan scafflod for bone tissue engineering. MethodsMWCNT/n-HA/CS scaffolds wre generated by solution blending and freeze-drying technology.The morphology and composition of the scaffolds were analyzed by scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy, after this, the results of which mixed CNTS in scaffolds were evaluated. The effects of MWCNT/n-HA/CS scaffolds on adherence and proliferation of rabbit bone marrow stroma cells were assessed by scaffolds surface seeding methods, and using scanning electron microscopy, MTT assay to observe their adhesion and proliferation on scaffolds.Results MWCNT/n-HA/CS scaffolds showed abundant homogeneous pores with (87.26％) porosity. 66％ fracture strength of the scafflod was improved by MWCNT,and porosity decreased by 3％. Conclusion MWCNT/n-HA/CS scaffold can be prepared with solution blending and freeze drying process, which has fair poriness, good mechanical strength and tissue compatibility and can be applied as a bone graft material.
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Objective To investigate the experiment effects of rabbit joint articular cartilage defects repaired by thermosensitive CS/PVA composite hydrogel engineered hTGF-β1 transfected bone marrow mesenchymal stem cells. Methods Bone marrow mesenchymal stem cells were isolated and cultured in vitro. The positive rate of transfection was defected by cell immunohistochemistry methods after Ad-hTGF-β1 transfected for 1 week. Twenty-four adult New Zealand white rabbits with full articular cartilage defects were randomly divided into 4 groups, each group had 6 animals, both hind limbs were used in the experiment. Group A: hydrogel combined with transfected cells; Group B: hydrogel combined with untransfected cells; Group C: hydrogel group; Group D: blank control group. Specimens and histological observation were used to evaluate the repair effect after 16 weeks according to Pineda's score. Results The positive rate of hTGF-β1 expression in BMSCs was about 85.4% after transfection. After 16 weeks the defects of group A were repaired by cartilage-like tissue, the cell arrangement and densities of regenerated cartilage were similar to normal cartilage, type Ⅱ collagen immunohistochemistry were positive. There was a significant difference in Pineda's score compaired with other groups (P ＜ 0.05). Conclusion Rabbit articiular cartilage defects could be repaired by CS/PVA hydrogel engineered hTGF-β1-transfected bone marrow mesenchymal stem cells.
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Objective To investigate the feasibility of Ad-hTGF-β1 transfected bone marrow mesenchymal stem cell(BMSCs) into chondrocytes differentiation and the change of TAZ mRNA. Methods Rats BMSCs were obtained and cultured by whole bone marrow method, and then the third-generation cells were seeded into cell culture plate, and divided into three groups:Ad-hTGF-β1 transfected group,Ad-EGFP transfected group and the control group. The control group was added in common medium without any treatment while the other two groups were respectively added in serum-free medium containing Ad-hTGF-β1 or that containing Ad-EGFP. Seven days later, real-time fluorescent quantitation PCR and Western blot were employed for detecting the expression of TGF-β1 ,while immunohistochemical and Western blot for the expression of collagen Ⅱ , and real-time fluorescent quantitation PCR for the expression of TAZ mRNA. Results Seven days after the transfection, real-time fluorescent quantitation PCR revealed that the average relative expression of TGF-β1 was:Ad-hTGF-β1 group 0.863, Ad-EGFP group 0.183, and the control group 0.180; The average relative expression of TAZ was:Ad-hTGF-β1 group 0.810, Ad-EGFP group 0.416, and the control group 0.366.The expression difference of TGF-β1 and TAZ were statistically significant (P ＜ 0.05). Western blot and immunohistochemical proved strong collagen Ⅱ expression in Ad-hTGF-β1 group while it was detected a little in the other two groups. Conclusion BMSCs could be successfully and stably induced into chondrocytes differentiation by Ad-hTGF-β1. Meanwhile, the mRNA of TAZ is up regulate during the differentiation,so it is suppose that TGF-β1 improve BMSCs into chondrocytes differentiation by TAZ.
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In order to investigate the strength, structure and cell cytocompatibility of injectable thermosensitive chitosan (CS)/poly(vinyl alcohol) (PVA) composite hydrogel, chitosan hydrochloride solution was transferred to a neutral pH and mixed with different proportions of PVA, then the gelation time and strength of these different hydrogels were tested and spatial structures were observed under a scanning electron microscopy (SEM) after freeze-drying. The cytocompatibility of the hydrogels was evaluated through cytotoxicity test and three-dimensional culture with bone marrow mesenchymal stem cells. The results showed that the CS/PVA solution kept in liquid state at low temperature (0-4 degrees C) and turned into transparent elastomer about 15-20 min at 37 degrees C. Gelation time was prolonged, the strength increased and porous structure became dense with the PVA content increased in the mixed hydrogel. The cytotoxicity grades of these gels were from 0 to 1. Rabbit bone marrow mesenchymal stem cells could survive and proliferate in the gel within 3 weeks, and the gel had good cytocompatibility. It was concluded that thermosensitive CS/PVA composite hydrogel not only has interpenetrating network structure and better mechanical strength, but also has good cytocompatibility, and may be used as an injectable scaffold for tissue engineering.
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Objective To explore indications for replantation and amputation of complex severed lower legs. Methods Fifteen lower legs in 25 cases with complex severed lower limbs were replanted including four finally amputated again, and other 10 legs were amputated directly after trauma. Those with successful replantation were repaired with microsurgical technology and limb lengthening procedure for complications such as soft tissue defect, bone defect and limb shortening. The amputated cases were fitted with prosthetic limb after wound healing. Results All cases were followed-up for three to 10 years (6.4 years in average), and 11 lower legs were survived in 15 replanted cases and other four were finally amputated and fitted with prosthetic replacement. The limbs of those with successfully replantation shortened to varied extent, and one can be categorized as grade Ⅰ, four as grade Ⅱ, four as grade Ⅲ and two as grade Ⅳ, according to Chen's classification of function evaluation for replanted limbs. Appearance of prosthetic limbs in 14 cases had no significant difference from the normal, and 12 of them could walk with load and two had slight claudication. Those with prosthetic limbs were more satisfactory than those with replantation of the limbs. Conclusion Replantation for complex severed lower legs should be comprehensively considered based on mangled extremity severity score (MESS), their local condition and function prognosis.
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Objective To investigate the composite of chitosan(CS) and polyvinyl alcohol (PVA) as scaffold carrier for rabbit chondrocytes nurture and growth.Methods The third passage of chondrocytes were seeded in CS/PVA gel scaffold and 24,48 and 72 h after which cytoactive and toxicity were determined by MTT respectively.After one,two and three weeks,the growing status and morphology of chondrocytes in CS/PVA gel were observed with scaning electron microscope (SEM) and laser confocal scanning fluorescence microscope (LCSM).Results The third passage of chondrocytes in CS/PVA gel scaffold remained high proliferation ability.MTT measuring cell activity and virulence,the result showed that the number of cells obviously increased with the time,with statistical significance of difference between each groups (P＜0.05),without side effect to cells by the material.Observation of scaning electron microscope and confocal laser scanning fluorescence microscope showed that chondrocytes grew well with the scaffold of CS/PVA gel.Conclusion CS/PVA mixed gel material can be used as scaffold for rabbit chondrocytes growing for repairing cartilages defect in tissue engineering.
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BACKGROUND: A large amount of cell dies of apoptosis in secondary injury stage after spinal cord injury.OBJECTIVE: To probe into the influence of local intraspinal infusion with danshen injection on necrosis and apoptosis of spinal cell after acute spinal cord injury.DESIGN: Randomized controlled experiment was designed.SETTING: Clinical Medical Trial Center of People' s Hospital Affiliated to Yunyang Medical College.MATERIALS: Forty-four Chinese white rabbits of first grade were employed, aged varied from 4 to 5 months, of either sex, mass weighted varied from 2.0 to 2.5 kg.INTERVENTIONS: The experiment was performed in Clinical Medical Trial Center of People' s Hospital Affiliated to Yunyang Medical College from June 2002 to July 2003. Two groups were randomized, named danshen group and the control group, 22 rabbits for each. In both groups, modified Allen method was used to prepare the model of incomplete spinal cord injury. In danshen group, danshen injection was infused from subdural catheter for 4times at 0. 3 mL/kg per day of the total amount (once every 6 hours). In the control group, physiological saline of same dose was injected. The animals were sacrificed at the 8th, 24th and 72nd hours successively after injection for pathological and histomorphologic observation, peroxide dismutase and malondialdehyde determination and determination of positive cell count of B-cell lymphoma-2 (Bcl-2), the apoptosis-inhibition gene.MAIN OUTCOME MEASURES: Cell apoptotic index and cell apoptotic rate in the region of spinal cord injury.RESULTS: Forty-four rabbits entered result analysis for all. ① Results of cell apoptosis: Apoptotic index in danshen group was less remarkably than that in the control group(13.10 ± 1. 38, 20.39±2.96, 4.101, P ＜0.01); cell apoptotic rate was lower remarkably than the control group[ (9.67 ± 1.09)%,(14.68±2.81)%, t=4.072, P ＜0.01] and Bcl-2 expression was more than that in the control group[ (19. 12 ± 4.74) /mm2, ( 13.37 ± 3.68) /mm2,t = 2. 347, P ＜ 0.01 ]. ② POD content: The result in danshen group was higher thanthe control group[ (136.20 ± 13.64) NU/mL, (101.70 ± 15.24) NU/mL,t = 4. 132, P ＜ 0.01 ]. ③ Malondialdehyde content: The result in danshen group was lower than the control group[ (1.27 ± 0. 22) nmol/mL,(2.54±0.69) nmol/mL, t=4.309, P ＜0.01] . ④Degeneration and necrosis of neuron and neural fiber: The result in danshen group was milder than the control group.CONCLUSION: After local infusion with danshen(Radix Salviae Miltiorrhizae), cell apoptosis was decreased in local spinal cord injury and cell necrosis was inhibited and alleviated after acute spinal cord injury.