In order to repair cartilage defect in joint with transplantation of cryopreserved homologous embryonic periosteum, 30 rabbits were used and divided into two groups. A 4 mm x 7 mm whole thickness cartilage defect was made in the patellar groove of femur of each rabbit. The homologous embryonic rabbit skull periosteum (ERSP), preserved in two-step freezing schedule, was transplanted onto the cartilage defect of joints of one group and autogenous periosteal graft was done in the joint defect of the other group. The knees were not immobilized, following operation and 16 weeks later, the newly formed tissue in the defects were assessed by gross observation, histochemical examination and biochemical analysis. The results showed that new hyaline-like cartilage was formed in the cryopreserved ERSP grafted knee, and had no significant difference from that of the knee receiving autogenous periosteal graft, but had significant difference from that of the fresh ERSP grafted knee and the non-grafted knee. Furthermore, the new hyaline-like cartilage had the biochemical characteristics of a fibrous cartilage. The conclusion was that this method might be feasible to repair articular cartilage defects.
【Abstract】ObjectiveTo investigate the effects and mechanism of Panax Notoginseng saponins (PNGS) on rat liver during cold preservation. Methods Using isolated perfusion of rat liver model (IPRL), Fura-2 method was used to measur the concentration of calcium ion in hepatic cells which had been preserved in DMEM solution with different concentration of PNGS added and cold preserved for 2 hours. Liver function, metabolic products of oxygen free radicals, energy substance and aucount of biliary flow as well as morphological study were measured from liver tissue which had been cold preserved in lactate riuges’s solution containing different dosages of PNGS for 24 hours and 30 minutes reperfusion.ResultsThe contents of intracellur calcium of the rat hepatocytes,MDA, AST, ALT, LDH were lower than those in the control group,but SOD, ATP, TAN, EC and bile production were higher than those in the control group(P＜0.01).During 200-600 mg,the protective effects of the PNGS were correlated with the dosage and manifest dosagedependence(Plt;0.01),800-1000 mg were not significant(Pgt;0.05). ConclusionPNGS relieve the injury of the rat liver during cold preservation. The mechanism might through inhibition calcium overload, improve the energy metabolism, play a role against free radical injury realize.
ObjectiveTo study the preservation effect of true bone ceramics (TBC) prepared by high-temperature calcination of bovine bone on alveolar ridge of canine extraction socket.MethodsSix healthy Beagle dogs (aged 1.5-2 years) were selected to extract the second and fourth premolars of both mandibles and the second premolars of the maxilla. The left extraction socket was implanted with TBC as the experimental group, and the right side was implanted with the calcined bovine bone (CBB) as the control group, to observe the alveolar ridge preservation effect. Three dogs were euthanized after general observation at 1 and 6 months after operation respectively. After separating the maxilla and mandible, cone beam CT (CBCT) was performed to measure the average gray value of the graft site and the adjacent reference area (the area between the roots of the adjacent third premolar) and calculate the gray scale ratio between the bone graft site and the reference area. Histological observation was made on the bone graft site to evaluate the new bone formation.ResultsGeneral observation showed that the wounds of both groups were basically healed at 2 weeks after operation, and the bone graft materials were not exposed. The wounds healed well at 1 and 6 months after operation without swelling. The results of CBCT showed that the residual material was found in both groups at 1 month after operation, and no significant residual material was found in both groups at 6 months after operation, and the alveolar ridge height of the bone graft area was not significantly reduced. There was no significant difference in the bone mineral density between the experimental group and the control group. The gray scale ratios of the experimental group at 1 month and 6 months after operation were 0.97±0.14 and 0.93±0.06, respectively, and were 0.99±0.16 and 0.94±0.05 in control group, showing no significant difference between the two groups (t=?1.030, P=0.333; t=?0.770, P=0.466). HE staining observation showed that a large number of bone graft materials did not degrade and new bone formed around the grafts in both groups at 1 month after operation; the bone graft materials were absorbed and a large number of new bones were formed in both groups at 6 months after operation.ConclusionTBC can maintain bone mineral density and have good osteoconductivity in the alveolar ridge site preservation experiment of dogs, and can be used for alveolar ridge site preservation.
Objective To study the research method of cell survival rate at the procedure of cryopreservation of tissue engineered tendons.Methods In the 4thgeneration of human fibroblasts, the dead cells were stained with propidium iodine (PI), while the living cells with Hoechst 33342(Ho). The living cells and dead cells emitted fluorescence of red and blue respectively after they were stimulated by suitable ultra-violet, then flow cytometry was applied to distinguishthem. The seeding cells were collected to make them to be the cell suspension of suitable concentration(6.0×105 cell/ml) before they were divided into two parts. We cryopreserved and defrosted one part three times to kill the cells and didnot cryopreserve the other part, then we made cell suspension at different ratios of cryopreserved cell to noncryopreserved cells. The fluorescence staining and flow cytometry were used to study the correlation between cell ratios of cryopreservedcell to non-cryopreserved cell and the cell survival rates. We compared the cll survival rates between immediate flow cytometry and that 2 hours after fluorescence staining. Results The results of flow cytometry showed that correlation between the ratio of cryopreservation and the cell survival rate was significant (r=0.970，Plt;0.05), image analysis study also showed the correlation was significant (r=0.982，Plt;0.05).The cell survival rate decreased by use of flow cytometry twohours after fluorescence staining, but there was no significant difference when compared with that of immediate flow cytometry (Pgt;0.05). We could also observe the cells on the tissue engineered tendons by fluorescence image directly.Conclusion Flow cytometry and fluorescence image afterPI and Ho staining is a good way in study cell survival rate at the procedure of cryopreservationof tissue engineered tendons.
ObjectiveTo analyze clinical experience and outcomes of bileaflet preservation in mitral valve replace-ment (MVR) for patients with severe mitral regurgitation (MR).
MethodsWe retrospectively analyzed clinical data of 17 patients with severe MR who underwent MVR with bileaflet preservation in the Department of Cardiovascular surgery of Guangdong General Hospital from June 2011 to January 2013. There were 14 males and 3 females with mean age of 63.41±11.82 years (range, 38 to 82 years). There were 13 patients with atrial fibrillation. Preoperatively, 5 patients were in New York Heart Association (NYHA) functional class Ⅲ, and 12 patients were in NYHA class Ⅳ. There were 7 patients with ischemic MR, 9 patients with degenerative MR, and 1 patient with rheumatic MR.
ResultsMVR with bileaflet preservation was performed for all the patients. Concomitant coronary artery bypass grafting was performed for 4 patients. Eleven patients received bioprosthetic MVR, and 6 patients received mechanical MVR. There was no in-hospital death, postoperative low cardiac output syndrome or left ventricular rupture. All the 17 patients were followed up for a mean duration of 16.44±5.02 months (range, 2 to 25 months). During follow-up, 1 patient died of severe paravalvular leak 2 months after surgery. All the other patients had good mitral valve function. None of the patients had anticoagulation or prosthetic valve related complication. Patient's heart function was significantly improved. Eleven patients were in NYHA functional class Ⅰ, 4 patients were in NYHA class Ⅱ, and 1 patient was in NYHA class Ⅲ. Cardiothoracic ratio, left atrial dimension, left ventricular end-diastolic dimension and left ventricular end-systole dimension postoperatively and during follow-up were significantly smaller than preoperative values. Postoperative left ventricular ejection fraction (LVEF) was significantly lower than preoperative LVEF(50.94%±8.78% vs. 55.31%±10.44%, P=0.04), but LVEF during follow-up was not statistically different from preoperative LVEF(55.31%±10.44% vs. 56.13%±9.67%, P=0.73), and LVEF during follow-up was significantly higher than postoperative LVEF(56.13%±9.67% vs. 50.94%±8.78%, P=0.02). There was no statistical difference between postoperative mitral pressure half-time (PHT)and PHT during follow-up (95.06±19.00 ms vs. 94.56±19.19 ms, P=0.91).
ConclusionMVR with bileaflet preservation is a safe and effective surgical technique for patients with severe MR, and can significantly improve postoperative left ventricular remodeling and function.
【Abstract】ObjectiveTo compare the effects of self-designed KYL solution on rat liver preservation with UW solution. Methods Using non-circulated isolated perfused rat liver,SD rat livers were randomly preserved for 0、4、8、16、24 and 48 hours with self-designed KYL solution or UW solution. The effects were assessed by measuring the bile production, the contents of AST， ALT，LDH，free radical（ MDA） and SOD in KrebsHenseleit’s perfusate and the content of intracellar calaium of the rat hepatocytes, and by observing the morphological changes in liver. At the same time, the normal saline was used to preserve the rats liver as negative comparison to know if KYL solution and UW solution can prevent the ischemiareperfusion injury in rat liver transplantation.Results At different periods within 16 hours of preservation,the bile production of the rat livers which were preserved by KYL solution were more than those were preserved by UW solution （P＜0.01）, JP2The contents of AST， ALT and LDH in Krebs-Henseleit’s perfusate were near in UW solution’s. The content of intracellar calaium of the rat hepatocytes which were preserved by KYL solution were less than those were preserved by UW solution （P＜0.01）. In KYL group, the content of MDA was lower than that UW group, the content of SOD was higher than that UW group at 24 and 48 h(P＜0.01). Morphological changes in both groups were almost same. All variables of both groups were better than the rat livers preserved by the normal saline. It was proved that both KYL solution and UW solution could protect the rat livers. Conclusion The study indicated that the effects of self-designed KYL solution on rat liver preservation are similar to that of UW solution. The bile production after reperfusion and the content of intracellar calaium of the rat hepatocytes in KYL group are better than those in UW group .The effect of prevention of rat hepatocellular oedema by self-designed KYL solution are worse than that of UW solution.
Objective To elucidate the protective effect of leukocyte depletion on the myocardium during the settings of myocardial reperfusion injury. Methods Twenty patients undergoing cardiopulmonary bypass with continuous infusion of blood cardioplegia were randomized into two groups:the control group (n=10) with no leukocyte depletion filter used, and the experimental group (n=10) with the use of leukocyte depletion filter on the bypass circuit. The blood cells count before and after the filtration were measure...
Objective\ In order to assess and evaluate the clinical results of cold blood cardioplegia and intermittent cross clamping as myocardial preservation in coronary artery bypass grafting(CABG).\ Methods\ According to the management methods, 2 013 cases for elective, isolated CABG were divided into two groups at St.George’s Hospital, London.Cold blood cardioplegia group: 596 patients treated with cold blood cardioplegia, and hypothermic ventricular fibrillation group: 1 417 patients treated with intermitt...
Abstract In order to study the possibility of repairing bone defect by cryopreserved vascularized bone allograft, 8 dogs were divided into 2 groups. In the experimental group, 15% dimethylsulfoxide (DMSO) was used as a cryoprotective agent, the posterior segments of dog s rib, pedicled with intercostal vesseles, were cryopreserved by a two-step freezing procedure,stored in liquid nitrogen for 96 hours, and then transplanted as allografts to theiliac bone defects of recipients by vascular anastomosis. In the control group, the autografts were transplanted in the same procedure. Immunosuppersive agents were administrated postoperatively for 3 weeks. The specimens were analyzed by immune response monitoring (IL-2, T cell subsets), SPECT scanning, angiography and pathologic examination. The results showed that the allografts had good blood supply and active osteocyte metabolism, bone healing of the allografts was perfect at 3 months and no evidence of immunologic rejection. The process of bone healing of allografts should be further investigated.
ObjectiveTo compare the recovery of proprioception of the knee after the anterior cruciate ligament (ACL) reconstruction with remnant preservation or not.
MethodsBetween January 2010 and October 2012, 40 patients with ACL rupture were divided into remnant preservation reconstruction group (trial group, n=20) and traditional reconstruction group (control group, n=20). There was no significant difference in gender, age, disease duration, injury causes, preoperative Lysholm scores, and preoperative International Knee Documentation Committee (IKDC) scores between 2 groups (P>0.05). All the patients received ACL single-bundle reconstruction surgery with autologous hamstring tendon transplantation under arthroscope. After operation, the function of knee was assessed by Lysholm and IKDC scores and the proprioception was assessed by joint position sense (JPS) value which was evaluated by passive repeat angle test with isokinetic test system.
ResultsAll incisions healed by first intention in 2 groups. The patients were followed up 12-16 months (mean, 14.0 months) in trial group, and 12-15 months (mean, 14.5 months) in control group. At 12 months after operation, the Lysholm and IKDC scores were significantly increased when compared with preoperative scores (P<0.05) in both groups, but no significant difference was found between 2 groups (P>0.05). At 3 months and 12 months after operation in trial group, the JPS values of operated knee at 15, 45, and 75° of flexion were significantly lower than preoperative values (P<0.05), but no significant difference was found between at 3 months and at 12 months after operation (P>0.05). At 3 months after operation in control group, there was no significant difference (P>0.05) in JPS values of operated knee at 15, 45, and 75° of flexion when compared with preoperative ones; but at 12 months after operation in control group, the JPS values of operated knee at 15, 45, and 75° of flexion were significantly lower than those at preoperation and at 3 months after operation (P<0.05). At 3 months after operation, the JPS of operated knee at 15, 45, and 75° of flexion in trial group were significantly lower than those of operated knee in control group (P<0.05), but no significant difference was found between 2 groups at 12 months after operation (P>0.05). At 3 and 12 months after operation in trial group, there was no significant difference (P>0.05) in JPS values at 15, 45, and 75° of flexion between operated and normal knees; at 3 months after operation in control group, the JPS values of operated knee at 15, 45, and 75° of flexion were significantly higher than those of normal knee, but there was no significant difference between operated knee and normal knee at 12 months after operation (P>0.05).
ConclusionACL reconstruction with remnant preservation is helpful for recovery of proprioception in knee joint at early stage.
