Dec 2019 DOI 10.14302/issn.2577-2279.ijha-19-3110
N.A. KiryanovCorresponding author
Izhevsk State Medical Academy, Izhevsk, Russia
Aim To study the chondroplasty efficacy of the bone matrix obtained using an original technology in restoring cartilage defect of the knee joint. Material and Methods Marginal defects were modeled on the surface of the distal end of the femur in 40 adult male Wistar rats. The bone matrix obtained using an original technology was implanted in the damaged area in animals of the experimental group. Material was investigated by means of light microscopy, transmission and scanning electron microscopy, and electron probe X-ray microanalysis. Results It was found that the bone matrix implanted did not cause an immune rejection reaction, activated reparative chondrogenesis for a prolonged period. In the area of articular cartilage lesion, the regenerate acquiring cellular and histochemical characteristics of the hyaline cartilage tissue was formed. The chondroinductive properties for the bone matrix were ensured by localized growth factors and morphogenetic proteins released during osteoclastic resorption. Conclusion The application of the bone matrix as a stimulator of chondrogenesis is theoretically reasonable and has a good perspective in treatment of damages and diseases of the articular cartilage.
Jan 2013 DOI 10.14302/issn.2329-9487.jhc-12-102
M. R. Lacerdaa CarlaCorresponding author
Department of Clinical Sciences, Colorado State University, Fort Collins, CO 80523.
Background: Heart valves share developmental signaling pathways with cartilage and bone. While calcific aortic valve disease (CAVD) has been associated with valve calcification and stenosis, suggestive of osteogenesis, myxomatous mitral valve disease (MMVD) is characterized by net matrix degradation, exuberant deposition of proteoglycan, and valve regurgitation. Methods: We determined the presence of cartilage-abundant proteoglycan, aggrecan; cartilage-specific type II collagen; chondrogenic transcription factor, Sox9; and osteogenic transcription factor, Runx2 in human normal and myxomatous mitral valve leaflets by immunohistochemistry. Results and Conclusions: Myxomatous, but not normal, mitral valves demonstrated sharp focal areas that were abundant in aggrecan, type II collagen, and Sox9. These focal areas co-localized with areas of myxomatous pathologic change on Movat staining. Some cells in these areas had a round and hypertrophic morphology reminiscent of chondrocytes. Runx2 was only weakly present in normal and myxomatous mitral valves. These findings suggest a focal pathologic process in MMVD that mimics chondrogenesis.