From the results of this experiment, it showed that the implanted tendon was gradually extruded from the tibia hole and attached to the periosteum. The dominant breeding of tissue cells, cytodynamics, the perimeter ratio of tendon/bone and the effect of revascularization were discussed in detail.
A mechanical study on the bones of 29 rabbits following implantation of carbontendon was carried out. The rabbits were divided into seven groups according to the observation time (2,4,6,8,12,20 and 30 weeks after operation). A bundle of artificial tendon composed of 7,000 carbon fibers was passedthrough a tunnel in the tibia, and both ends of the artificial tendon were ligated to the muscle fibers. The mechanical strength and histological structure of the carbonbone junction and their relationship were studied in each group. Carbon fiberwas split and degradated in six to eight weeks after operation. The tensile strength of carbontendon in the soft tissue was decreased from 82±4.6N in the second week to 27±5.31N and6.3±1.81N in the sixth and eighth week respectively. The tensile strength of carbontendon increased from 3.01±1.2N to 6.1±2.01N at the carbon -tendon-bone junction in the bone. The tensile strength of carbon-tendon was unsatisfactory for implantation into bone. The carbon-tendon was split and degradated and the tensile strength was not b enough to cope with the early functional exercises.
Objective To investigate the possibility of repairing defected tendon with a tissue engineering tendon, combined culture of allogenous tenocyte and derived tendon. Methods Macaca tenocytes labelled by BrdU were seeded on the derived tendon. The flexor digitorum profundus of five fingers of left hand in 15 Macaca mulatta were resected and made 2.5cm defects as experimental model. They were divided into three groups according to repair methods (Group A: Combined culture of derived tendon materials and alloggenous tendon cells; Group B; Derived tendon materials; Group C; Autograft). In different stages, the labeled BrdU of tendon cells were observed. Results In Groupo A, after iin vivo implantation, the tenocytes could proliferate and synthesize collagen; the new tissue was white and glossy and the collagen fibers fused to form dense tendon structure as several weeks passed. Twelve weeks after implantation, the tenocytes still survived and synthesized collagen, the results of labelled cells were positive by immunothistochemical methods. By scanning electron microscopic observation, the tenocytes arraged regularly and evely among the derived tendon; the collagen fibers formed a network and its main direction was accord with that of the derived tendon. Normal nucleus, nucleolus, and cell organelles were seen under transmission electron microscope. Conclusion Combined culture of tenocytes with derived tendon is able to make tendon like tissue. The structure of tissue engineering tendon in similar to that of normal tendon.
Objective To observe the expression of related proteins of retina after subretinal implantation with inactive chips.Methods A total of 27 healthy adult New Zealand white rabbits were randomly divided into three groups: operation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina;shamoperation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina which was taken out immediately;the control group (3 rabbits). Animals were sacrified for immunohistological study 7,15,30 and 60 days after surgery.The rabbits in control group group were sacrified for immunohistological study after bred for 30 days.The expressions of glial fibrillary acidic protein (GFAP) and brain derived neurotrophic facor (BDNF) were observed.Results In operation group, the outer nulear layer of retina thinned, and the cells in the inner nulear layer was disorganized 7,15,and 30 days after the surgery;glial cells proliferated 60 days after surgery; the positive expression of BDNF and GFAP was more than that in the shamoperation and control group.In shamoperation group, the positive expression of BDNF and GFAP was more than that in the control group.No obvious difference of expression of BDNF and GFAP between each time point groups was found.Conclusions The expression of neroprotective related proteins increased after subretinal implantation with inactive chips suggests that limited neuroprotective effects might be led by the implantation.
Objective To investigate whether the implanted myoblasts with the soluble carriers can improve the repairing efficiency for theseverelycryodamaged tibialis anterior muscles. Methods The skeletal myoblasts were isolated from the newborn SD rats by the use of the enzyme digestion. They were purified and serially subcultivated; the subcultivated myoblasts of the 3rd generation were marked with BrdU. The severelycryodamaged tibialis anterior muscle models were established from 84 SD rats aged 5 months. They were randomly divided into 4 groups, including Group A1 (the implanted myoblasts with the carriersF12 containing 0.1% sodium hyaluronate), Group A2 (the implanted myoblasts, with the carriersF12 that did not contain 0.1% sodiumhyaluronate), Group B1 (the implanted carrier solution containing 0.1% sodium hyaluronate, but with no myoblasts), and Group B2 (with no carrier solution or myoblasts). Six rats were killed at the following time points: at 2, 5 and 9 days,and 2, 4, 8 and 12 weeks after operation; the immunohistochemical and the Mallory staining studies were performed for an evaluation on the repairing efficiencyfor the severelycryodamaged tibialis anterior muscles. By the imaging analysis, the number of the survived cells in each group was compared at 2 days, and the area ratio of the collagen fiber in each group was also compared at 8 weeks. Results The BrdU immunohistochemical staining showed that the number of the remaining implanted cells was significantly greater in Groups A1 than in Group A2, the migrating area of the myoblasts was greater, the distribution of the cells was more uniform, the cell differentiating potential was undestroyed, the repairing efficiency for the severelycryodamaged tibialis anterior muscles was significantly improved. There was no bluestained nucleus at each time point in Group B. The Mallory staining showed that the fibrous degeneration inthe tissue repairing process was significantly inhibited in Groups A1, A2 and B1; the inhibition was most obvious in Group A1, and next in Group A2. The imaging analysis indicated that at 2 days after operation, the number of the survived cells was significantly-greater in Group A1 than in Group A2 (Plt;0.05). At 8 weeks after operation, the collagen fiber was the least in Group A1, less in Group A2, more in Group B1,and the most in Group B2 (Plt;0.05). Conclusion The implanted myoblasts can significantly improve the repairing efficiency for the severelycryodamaged muscle tissues, and the implanted carrier solution containing 0.1% sodium hyaluronate can improve the implanting efficiency for the myoblasts.
In order to observe the role of genetically modified Schwann cell (SC) with pSVP0Mcat in the regeneration of injured spinal cord, the cells were implanted into the spinal cord. Ninety SD rats were used to establish a model of hemi-transection of spinal cord at the level of T8, and were divided into three groups, randomly, that is, pSVP0Mcat modified SC implantation (Group A), SC implantation (Group B) and without cell implantation as control (Group C). After three months the presence of axonal regeneration of the injured spinal cord was examined by means of horseradish peroxidase (HRP) retrograde labelling technique and stereography. The results indicated that HRP labelled cells in Group A and B could be found in the superior region of injured spinal cord and the brain stem such as the red nuclei and oculomotor nuclei. The density of ventral hom neurons of the spinal cord and the number of myelinated axons in 100 microns of the white matter was A gt; B gt; C group. In brief, the pSVP0Mcat modified SC intraspinal implantation could promote regeneration of the injured spinal cord.
ObjectiveTo explore the antitumor effect of tumor vaccine fused from dendritic cells (DC) and Walker-256 cancer cells on implanted liver cancer in rats and the related mechanism of inhibition for tumor angiogenesis. MethodsWalker-256 cancer cells and mature DC were fused by 50% polyethylene glycol method for preparation of DC-Walker-256 fusion vaccines. Implanted liver cancer models were established through operations on healthy male SD rats at the age of 6－8 weeks. All the rats were divided into four groups, and rats in each group were injected subcutanely with fusion vaccine (group), mixed cultured cells (group), simple DC (group), and PBS (blank control group), respectively. On 28 d after making model, the rats were put to death, the tumor was observed and pathological essays were prepared. All rats’ spleens were collected and prepared into lymphocyte to detect antigenic specificity cytotoxic T lymphocyte (CTL) by enzymelinked immunosorbent spot (ELISPOT) method. The expressions of VEGF, ANG-1, ANG-2, and MVD were detected by immunohistochemistry. ResultsThe numbers of rats survived in the fusion vaccine group, mixed culture cells group, simple DC group, and blank control group was 8, 5, 6, and 3, respectively. The rats in the other three groups except for fusion vaccine group were manifested as inaction, anorexia, and gloomy fur in some degree as well as ascites. The tumorigenesis was found in all survival rats except for two in the fusion vaccine group. The weight of liver tumors of rats in the fusion vaccine group 〔(32.4±9.2) g〕 was significantly lighter than that in the mixed culture cells group 〔(67.3±5.1) g, P=0.031〕, simple DC group 〔(75.0±8.3) g, P=0.019〕, and blank control group 〔(86.6±10.5) g, P=0.008〕, respectively. The number of tumorspecific CTL of rats in the fusion vaccine group was also significantly higher than that in the other three groups (P=0.019, P=0.025, and P=0.001, respectively). The MVD of tumor tissue in the fusion vaccine group was (24.12±2.32) vessels/HP, which was significantly lower than that in the mixed culture cells group 〔(40.34±1.29) vessels/HP, P=0.025〕, simple DC group 〔(42.36±3.16) vessels/HP, P=0.035〕, and blank control group 〔(56.48±5.16) vessels/HP, P=0.006〕, respectively. The MVD of tumor tissue in the mixed cultured cells group and simple DC group was similar (P=0.165), however, which was significantly lower than that in the blank control group (P=0.040 and P=0.043). The positive rate of VEGFA protein expression was 23.2% in the fusion vaccine group, which was significantly lower than that in the mixed culture cells group (42.5%, P=0.031), simple DC group (61.3%, P=0.019), and blank control group (89.6%, P=0.003), respectively. The positive rate of VEGF-A protein expression in the mixed cultured cells and simple DC groups was similar (P=0.089), however, which was significantly lower than that in the blank control group (P=0.027 and P=0.038). The positive rate of ANG-1 protein expression in the fusion vaccine group (43.2%) was not different from that in the mixed culture cells group (46.3%, P=0.292), simple DC group (51.3%, P=0.183), or blank control group (49.6%, P=0.179), respectively, and the difference of pairwise comparison in latter three groups was not significant (P=0.242, P=0.347, and P=0.182). The positive rate of ANG2 protein expression was 19.2% in the fusion vaccine group, which was significantly lower than that in the mixed culture cells group (62.3%, P=0.007), simple DC group (67.3%, P=0.005), and blank control group (71.6%, P=0.004), respectively, however, the difference of pairwise comparison in latter three groups was not significant (P=0.634, P=0.483, and P=0.379). ConclusionFused vaccine can induce CD8+ CTL aiming at tumor cells and establish the effective antitumor immunity in vivo and also downregulate the level of VEGF and ANG-2 to suppress tumor angiogenesis and thereby achieve the purpose of curing tumor.
Objective To investigate the biocompatibility of acellular urinary bladder submucosa (AUBS). Methods The acellular collagen matrix of human urinary bladder submucosa was developed using freeze-thawed enzymatic treatment and freeze-drying technique. Human oral keratinocytes were cultured and seeded on AUBS at a density of 2×106/ml in vitro.The proliferation of the cells were observed. Pockets were created in the abdominal muscle wall of 18 SD rats. AUBS in size 1 cm×1 cm was implanted into the pocket. The grafts were observed by light microscope 3, 6, 10, 14, 21 and 28 days after operation. Results AUBSmainly consisted of collagen fibers with a three-dimensional network structure. After the oral keratinocytes were seeded, continous oral epithelium layer was formed on the surface of AUBS after 10 days in vitro. Histological observation of the grafted AUBS showed progressive cell infiltration at 6 days. New capillaries formed at 14 days. The collagen fibers arranged regularly at 28 days after implantation. Conclusion Freeze-dried AUBS may be used as a suitable scaffold for tissue regeneration, which can induce cell proliferation both in vivo and in vitro and has good biocompatibilty.
In order to study the Titanium-bone interaction and integration mechanism, the titanium implant was implanted in the tibia of 9 Newzealand rabbits, and the Ti-bone interface performed for 1, 3, and 6 months were examined and analyzed by fluorescence microscope and advanced TOF-SIMS techniques. The results showed that Ti-bone tissue was integrated closely in a very reactive manner. Both physical and chemical integration occurred in the Ti-bone interface. The Ti-bone could diffuse into the bone tissue though the diffusion was very limited. It was up to 100 microns in depth during the early period. The diffusion density was high, and later in a smooth distribution. Furthermore, while Ti+ diffused into the bone tissue, other elements such as Ca+, OH-, O-, etc, could also diffuse into titanium in exchange. The growth pattern around the bone tissue was in two fashions, one was implantefugal and the other was implantopetal. In this study, based on the ionic distribution, osmosis and impurity elements distribution, the Ti-bone integration mechanism was discussed at molecular and atomic level.
ObjectiveTo systematically evaluate the efficacy and safety of 125I seed interstitial implantation for lung cancer. MethodsWe searched PubMed, The Wiley Online Library, Elsevier, CNKI, VIP and WanFang Data from inception to February 2014 to collect randomized controlled trials (RCTs) of 125I seed interstitial implantation in the treatment of lung cancer. Two reviewers independently screened literature, extracted data and assessed the risk bias of included studies, and then meta-analysis was performed by using RevMan 5.1 software. ResultsA total of 23 RCTs involving 1 492 patients were included. The results of meta-analysis showed that:the effective rate (OR=3.43,95%CI 2.71,4.33,P<0.000 01), 1 year survival rate (OR=2.83, 95%CI 2.03 to 3.95, P<0.000 01) and 2 year survival rate (OR=2.49, 95%CI 1.60 to 3.88, P<0.000 01) in the 125I seed interstitial implantation group were higher than those in the control group, but the rate of postoperative complications was higher than that of control group (OR=19.72, 95%CI 11.63 to 33.45, P<0.000 01). In addition, there were no significant differences between both groups in the 3 year survival rate (OR=2.45, 95%CI 0.21 to 28.89, P=0.48) and the adverse reaction rate (OR=0.74, 95%CI 0.52 to 1.05, P=0.09). Conclusion125I seed interstitial implantation is effective in the treatment of lung cancer. It can improve treatment efficiency and short-time survival rate, but may increase the rate of complications such as pneumothorax, seed malposition, bleeding and so on. Due to the limited quality and quantity of included studies, more high quality and larger sample studies are needed to verify the above conclusion.