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.
OBJECTIVE: To evaluate the clinical effect of drilling procedure following the hydroxyapatite orbital implantation. METHODS: From February 1996 to April 2000, 146 consecutive patients who received hydroxyapatite orbital implant were drilled and inserted a motility peg 6 to 16 months after hydroxyapatite implantation. Among them, there were 97 males and 49 females, aged from 18 to 60 years old, of the 146 motility pegs, 36 were sleeved pegs and 110 were nonsleeved. Goldman visual field analyzer was applied to measure the degree of artificial eye’s movement before and after drilling. RESULTS: Followed up for 1 to 40 months, no secondary infection occurred. The mobility of the prosthesis increased from (18.7 +/- 3.8) degrees preoperatively to (42.3 +/- 3.7) degrees postoperatively. CONCLUSION: The delayed drilling procedure and motility peg insertion improve the range of movement and the sensitivity of the artificial eye with a low rate of complications.
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.
The aim of this experiment was to study the osteogenesis in vivo of allogenic osteoblast combined culture with calcium phosphate composites. The osteoblasts were obtained by enzymatic digestion of periosteum from fibula subcultured to 13 generations, the cells were combined culture with hydroxyapatite and biphasic calcium phosphate. Subseguently, the composite was implanted into rabbits subcutaneously or intramuscularly. The blank material was implanted in the contralateral side as control. Four weeks later, all animals were sacrificed. All the implants were examined by gross observation, histological examination and EDXA. The results showed: 1. obvious ingrowth of connective tissue with very little inflammatory reaction; 2. new bone formation in the composites with deposit of Ca and P on the surface of osteoblast, but none in the blank materials; 3. no significant difference of new bone formation between the different sites of implantation or different materials, but those implanted intramuscularly had lamellae form of new bone while those implanted subcutaneously had only mineralization of extracellular matrix. The conclusion were: 1. the composites are biocompatible with prior osteogenesis property; 2. periosteal-derived allogenic osteoblasts obatined by enzymatic digestion could survive following implantation with bioactivity; 3. rich blood supply might be advantageous to new bone formation and its maturation.
Objective To investigate the effect of iodine-125 on inhibiting breast cancer growth and to explore its possible mechanism. Methods The animal model of the MCF-7 tumor was established firstly through injection of the cells into nude mice. The animals were divided into two groups before the implantation of the iodine-125 granule into the tumor mass: control group (n=40, to implant no-load seeds, non-iodine-125 radioelement) and experimental group 〔n=40, to implant iodine-125 seeds (1.48×107 Bq) when the length of tumor was 8-10 mm〕. The width and length of tumor, in order to calculate the volume, were measured every three days to observe tumor growth curve and to calculate the rate of the tumor inhibition. When the length of tumor was 15-20 mm in the control group, 30 nude mice were killed in every group to detect the weight of tumor and histopathological changes. Other ten nude mice of each group were remained to be observed the national life span and survival rate for 90 days. Results Within 90 days, the average survival time in control group and experimental group were significantly different (56.2 d vs. 74.8 d, P＜0.05). In control group the growth curve was continuously elevated, while experimental group showed a low flat curve. With iodine-125 treatment, the tumor growth decreased in experimental group with tumor inhibition rate 55.21%. The average tumor weight in control group and experimental group was (3.26±0.39) g and (1.46±0.17) g (t′=22.8962, P＜0.05). As compared with control group, under light microscope, the number of cancer cells was less, nuclear debris increased, and cancer structure was not obvious in experimental group. Conclusion This study suggests that iodine-125 seed may inhibit the growth of breast cancer, which may be involved in direct radiation breakdown of tumor cells or induction of apoptosis and inhabitation of tumor angiogenesis.
Objective To explore the effective autologous bone marrow stem cell dosage for treatment of severe lower limb ischemia. Methods From December 2003 to December 2004, 22 cases of bilateral lower limb ischemia were treated with autologous bone morrow cell transplantation. All the patients were randomly divided into two groups according to ischemia degree. In group A(severe ischemia side), the amount of transplanted autologous bone marrow cells was more than 1×108, and ingroup B(mild ischemia side), the amount was less than 1×105. A series of subjective indexes, such as improvement of pain, cold sensation and numbness, and objective indexes, such as increase of ankle/brachial index (ABI) and transcutaneous oxygen pressure (TcPO2), angiography, amputation rate, and improvement of foot wound healing were used to evaluate the effect of autologous bone marrow stem cells implantation. Results The rates of pain relief were 90.0% in group A and 16.7% in group B (Plt;0.01); the rates of cold sensation relief were 90.5% in group A and 5.3% in group B（Plt;0.01）;the improvement of numbness was 62.5% in group A and 9.1% in group B（Plt;0.01）. Increase of ABI was 31.8% and 0 in groups A and B respectively（Plt;0.01） at 4 weeks after implantation. Increase of TcPO2was 94.4% and 11.1% in groups A and B respectively（Plt;0.01） at 4 weeks after implantation. Twelve cases of angiography showed rich new collateral vessels in 100% of the limbs in group A while no remarkable new collateral vessel in group B. The amputation rates were 4.5% in group A and 27.3% in group B（Plt;0.05） at 4 weeks after implantation. The rate of improvement of foot wound healing was 75% in group A and there was no changein wound healing in group B after 4 weeks of implantation. Conclusion The effectiveness of autologous bone marrow stem cell implantation depends on the number of implanted stem cells. Effectiveness is expected in most patients if the implanted stem cell is more than 1×108, whereas there would be little effect if the cell number is less than 1×105.
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 investigate the possibility of repairing injuried tendon with living artificial tendon, after combining culture, subcultured autogenous tendon cells with carbon fibers were implanted into the calcaneous tendon of rabbits. In different stages, the synthesis of type I collagen and their relevant morphological changes were observed. The results showed as follows: after implantation, tendon cells continued proliferating. Four weeks after implantation, tendon cells were detached from the carbon fibers and proliferated and produced collagen among the carbon fibers. The collagen fibrils were linked with each other to formed a dense structure. In the linkage site, the collagen fibrils originated from the implants joined to that from the ruptured end of the tendon, which meaned that the implant was healed with the recipient tendon. Observed under scanning electronic microscope, the tendon cells were lined among the carbon fibers evenly and in order, the collagen fibrils joined each other and formed an network, the fibrils were lined parallel to the carbon fibers. Under transparent electron microscope, the nucleolus were clear and organelle were abundant.
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.
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.