No abstract available.
Cartilage* ; Growth Plate*

PURPOSE: To evaluate the effect of the chitosan-TGF-beta1 conjugate on articular cartilage defects of rabbits' knees MATERIALS AND METHODS: Full thickness cartilage defect(6mm, round shape) was made at both knees of 20 rabbits and, after the lapse of 3 days, chitosan-TGF-beta1(15ng/ml, 1ml) was injected into one side(experimental group) of knees and PBS(1ml) was injected into the other side(control group). 5 rabbits were sacrificed 6 weeks after the injection and the rest of 15 rabbits 12 weeks later. Then, gross morphology and histological evaluation(Mendelson scoring) was conducted. RESULTS: No arthritic findings was observed and histological results in the experimental group at 6(Ave. 11.3+/-1.5) and 12(Ave. 4.5+/-1.9) weeks postoperatively were superior to those in the control group at 6(Ave. 14.6+/-1.7) and 12(Ave. 9.8+/-2.2) weeks. Especially at 12 weeks, the experimental group was superior to the control group statistically in results of 5 subgroups except for filling of defects. The difference of two groups at 12 weeks was more remarkable than those at 6 weeks. CONCLUSION: Regeneration of something very close to normal cartilage was observed in the experimental group. It shows that the biological activity of TGF-beta1 is sustained by the action of conjugate with chitosan, through prolonged half life of TGF-beta1.
Cartilage ; Cartilage, Articular* ; Chitosan ; Half-Life ; Knee* ; Rabbits ; Regeneration ; Transforming Growth Factor beta1

OBJECTIVETo study the effect of gradually induced occlusal disorders on the expression of basic fibroblast growth factor (bFGF) of condylar cartilage in rat.

METHODSThe model of gradually induced occlusal disorders was established in rat. The expression of bFGF was examined by SABC technique of immunohistochemistry. The expression of bFGF was analyzed by amount of positive cells.

RESULTSbFGF was expressed positively in the proliferative cell layer, maturative layer and hypertrophical cell layer in the rat mandibular condyle cartilage. In control group, expression of bFGF increased from 2-week-old to 6-week-old, then it had a decrease during experiment. Compared with the control group, bFGF of experiment group was increasing at 2 week, 6 week and 8 week during experiment. But there was decreaseing at 4 week. There was no difference between young experiment group and the adult experiment group.

CONCLUSIONThe gradually induced occlusal disorders may lead to significant increase of expressiong of bFGF in condyle cartilage, which suggests that the bFGF may be involve in the procedure of repairing process of articular cartilage.

Histologically, Schmorl's nodes are defined as the loss of nuclear material through the cartilage plate, growth plate, and end plate into the vertebral body. Most Schmorl's nodes are asymptomatic, although there are some reports of symptomatic Schmorl's nodes, which should be treated similarly to vertebral compression fractures, with conservative treatment as the first choice. We report the case that we reduced the pain by blocking the ramus communicans nerve in a patient with Schmorl's node.
Cartilage ; Fractures, Compression ; Growth Plate ; Humans ; Nerve Block

The acquisition of human chondrocytes for transplantation and cartilage coverage presents a major problem as these cells dedifferentiate rapidly during expansion in monolayer culture. Dedifferentiated chondrocytes change their shapes, metabolic states, and programs of matrix biosynthesis. We initiated this study on the basis of the hypothesis that bFGF, VEGF, and micromass culture can influence both the proliferation and their ability to express COL2A1 gene as a chondrogenic marker and Cbfa1 gene as an osteogenic marker. Chondrocytes in monolayer and micromass culture with or without bFGF and VEGF in vitro were collected and analyzed. In results, bFGF stimulated the proliferation of chondrocytes in monolayer culture. VEGF also stimulated the proliferation, but was less effective. The phenotype of chondrocytes was gradually changed in monolayer culture. Chondrocytes expanded in the presence of bFGF became dedifferentiated. However, dedifferentiated chondrocytes fully maintained their potential for redifferentiation in response to environmental changes. After transferring in micromass culture, chondrocytes which expanded with bFGF demonstrated high COL2A1 expression that was biochemically comparable to primary chondrocytes. Chondrocytes which expanded with VEGF demonstrated high Cbfa1 expression in both monolayer and micromass culture with passage times. This study provides that bFGF is needed to expand chondrocytes during tissue cultivation and additional three-dimensional environment is needed to maintain their differentiated phenotype. VEGF initiates the osteogenic potential during the chondrocyte expansion especially in micromass culture.
Cartilage ; Chondrocytes* ; Humans* ; Phenotype ; Vascular Endothelial Growth Factor A*

OBJECTIVE: The purpose of this study was to analyze the effect of growth hormone treatment (GHT) on craniofacial growth in children of short stature. METHODS: Nineteen untreated children of short stature were referred from the Pediatric Department, Yeungnam University Hospital as a subject group. All subjects had lateral cephalograms taken before, after 1 year and after 2 years of growth hormone treatment. As a reference group, we selected 19 normal children with paired sampling who matched the subjects' age and sex, from the Department of Orthodontics, Kyungpook National University Hospital. RESULTS: Before GHT, anterior cranial base length and upper posterior facial height, posterior total facial height, mandibular ramus length, and mandibular corpus length were significantly smaller in the reference group. In angular craniofacial measurements, saddle angle and mandibular plane angle were larger. SNA and SNB were smaller in the reference group. After two years of GHT, growth hormone accelerated growth in several craniofacial components. The posterior total facial height, the anterior, posterior cranial base length, and the mandibular ramus length were increased. And the difference in mandibular plane angle and ANB values compared with the reference group was decreased. CONCLUSIONS: GHT over 2 years leads to a craniofacial catch-up growth tendency, which is pronounced in interstitial cartilage and condylar cartilage.
Cartilage ; Child ; Growth Hormone ; Humans ; Orthodontics ; Skull Base

OBJECTIVE: To investigate the effect of the anteroposterior cricoid split on cartilage growth. METHOD: The rabbits were killed 8 months after the surgery of anteroposterior cricoid split. The larynxes were harvested and the cross-sectional area of the cricoid cartilage were calculated. RESULT: There was no significant difference in the cross-sectional area of the cricoid cartilage of these three groups. CONCLUSION The anteroposterior cricoid split might have no adverse effect on subsequent growth of cricoid cartilage.
Animals ; Cricoid Cartilage ; growth & development ; surgery ; Laryngostenosis ; surgery ; Rabbits

To understand the expression of hoth TGF-beta l and II ligands and the receptors, artificial fracture was made on rat femur. Fracture callus and epiphyseul plate were stained immunohistochemically on 3rd. 7th, 14th, 21st, 42nd and 56th day after trauma. Polyclonal antibody was used to stain TGF-beta I and II ligands and receptors. At epiphyseal plate, both ligand and receptor were expressed from each cell in proliferating and maturing zone. But there was no difference between type I and II except expression time. TGF-beta II ligand and receptor were expressed earlier: they were expressed mostly by the cells at the zone of proliferating cartilage but TGF-beta1 ligand and receptor were expressed mostly hy the cells at zone of maturing cartilage. At fracture site, TGF-beta expression was observed from 3rd day after trauma and it reached its maximum intensity at 2 weeks. It decreased thereafter and disappeared at 6 weeks after trauma. In enchondral ossification area, TGF-beta expressing cells were scattered throughout the enchondral mass. In intramembranous ossification area, the ligands and receptors were expressed from the osteohlasts just heneath the periosteum. ln summary, TGF-beta ligands and receptors were expressed at epiphyseal plate and fracture callus. There was no difference between TGF-beta 1 and 2 expres.ion except the appearance time at epiphyseal plate. We could not draw any conclusion about ligand and rcceptor mechanism with this immunohistochemical staining.
Animals ; Bony Callus* ; Cartilage ; Femur ; Growth Plate* ; Ligands* ; Periosteum ; Rats ; Receptors, Artificial ; Transforming Growth Factor beta ; Transforming Growth Factor beta1

Platelet-derived growth factor(PDGF) is known to accelerate soft tissue fracture and periodontal bone healing, but little information is available for characterizing the healing of articualr cartilage. This study was designed to demonstrate the regeneration potential of pasteurized autogeneous osteochondral graft when PDFG was applied locally in vivo. Eighteen rabbits in two groups were used in the experiment. The free osteochondral fragment(1x1x1 cm) were taken from distal femur. The fragment were pasteurized in 65degrees C for 5 minutes. In experimental group(group II), the fragment were soaked in 0.25 mg/ml of recombinant human PDGF mixed 5 ml normal saline and reimplanted to the resected site, and followed with local administration of 0.25 mg/ml PDGF to knee joint. In control group(group I), the pasteurized fragment were reimplanted in the resected site without any treatments. The histologic characteristics of the transplanted autografts for three rabbits in each group were observed at 3, 5 and 7 weeks postoperatively. The results were as follows; Group II revealed the more favorable regeneration of articular cartilage, less arthritic changes and more mature arrangement of chondrocytes than group I. Even thought the cartilage is avascular and the regeneration capacity of pasteurized cartilage is severely limited, the regeneration of grafted articular cartilage is thought to be accellerated by increased newly formed blood vessels and soft tissues due to the diffusion of PDGF on grafted cartilage, and probably also by differentiation of mesenchymal cells in the initial stage of experiment. The results of this study suggest that local administration of PDGF could be used for the treatment of posttraumatic or degenerative arthritis and various cartilage damages.
Autografts ; Blood Vessels ; Cartilage ; Cartilage, Articular ; Chondrocytes ; Diffusion ; Femur ; Humans ; Knee Joint ; Osteoarthritis ; Platelet-Derived Growth Factor* ; Rabbits* ; Regeneration* ; Transplants*

Culture media supplemented with animal serum e.g. fetal bovine serum; FBS is commonly used for human culture expansion. However, for clinical application, FBS is restricted as its carry a risk of viral or prion transmission. Engineering autologous cartilage with autologous human serum supplementation is seen as a better solution to reduce the risk of transmitting infectious diseases and immune rejection during cartilage transplantation. The purpose of this study is to establish and compare the effects of 10% autologous human serum (AHS) and 10% FBS on the growth of chondrocytes and the formation of tissue engineered human articular cartilage.
Cartilage, Articular/growth & development ; Cartilage, Articular/*transplantation ; Cell Count ; Cell Division/physiology ; Chondrocytes/*cytology ; Culture Media ; *Serum ; *Tissue Engineering