Conservative care for patellofemoral pain.

Human sclera from different parts of the normal adult eye was analyzed for content of uronic acid and the distribution of specific glycosaminoglycan types. Uronic acid is widely determined as representative of glycosaminoglycans in biological substances and variations of about 2-fold were found. Differences of up to 50% were detected in the relative abundance of hyaluronic acid and of dermatan sulphate, depending on the site on the globe from which the sample was taken. Sclera from around the papilla was found to be rich in content of dermatan sulphate. Sclera from the posterior eyeball showed a higher percentage of chondroitin sulphate as compared with sclera from equator and limbus. Equatorial sclera was richer in hyaluronic acid than posterior sclera. Sclera from the posterior eyeball showed a higher content of uronic acid as compared with sclera from equator and limbus. This work is an addition to the understanding of the scleral biochemistry and this finding may have some relevance in connection with ocular disease, as the proteoglycans and their content of glycosaminoglycans play a key role in the regulation of collagen fibril assembly and in the biomechanical strength of collagen fibrils.

Regional glycosaminoglycans composition of the human sclera.

Out of 30 adult rabbits, 20 had one knee immobilized with a plaster of Paris cast for 6 or 12 weeks, and 10 rabbits were used as untreated controls. Prior to immobilization, 10 knees were injected with high-molecular weight hyaluronic acid. The articular cartilage of the femoral condyles was studied by light microscopy, whereas that of the patella and tibia was analyzed biochemically. Degenerative changes of the articular cartilage similar to those seen in arthrosis were observed after 6 weeks. The intraarticular injection of hyaluronic acid did not prevent these changes; instead, the reparative processes seemed inhibited.

https://www.tandfonline.com/doi/pdf/10.3109/17453679108994462

The effect of hyaluronic acid on cartilage in the immobilized rabbit knee

In the normal adult eye the content of uronic acid, hydroxyproline, hydroxylysine and proline from different parts of sclera was examined. Scleral samples from the posterior eyeball showed a higher content of uronic acid than the scleral samples from papilla, equator and limbus. Apart from a lower concentration of hydroxyproline in sclera from equator, no major differences in concentration of hydroxyproline, hydroxylysine or proline was found in sclera samples.

Collagen and uronic acid distribution in the human sclera.

The long-term effect of destruction of the pigment epithelium by sodium iodate on the biochemistry of rabbit sclera was studied in one group with intravenous injection of sodium iodate, and in a second group with injection of sodium iodate into the right eye. Intravenous treatment produced a non-significant increase in the uronic acid concentration. In the second group the untreated fellow eye was microscopically intact, but was shown (as the treated eye) to alter the concentration of uronic acid in different parts of the sclera. All eyes from treated animals exhibited changes in the relative content of the various glycosaminoglycans and in the content of hydroxyproline, hydroxylysine and proline. This work indicates that the pigment epithelium may play a key role in the control mechanism of the scleral connective tissue, and this again has major implications in terms of a possible medical treatment of axial myopia.

Biochemical changes in rabbit sclera following destruction of pigment epithelium.

We obtained samples of patellar cartilage at the time of surgery from 20 patients: 11 with normal and 9 with macroscopic cartilaginous degeneration. The glycosaminoglycans were separated by cellulose acetateelectrophoresis, and the relative content of major glycosaminoglycans was measured by optic scanning. The total content of glycosaminoglycans was estimated by uronic acid analysis. We found that degenerated cartilage contained an increase in dermatan sulfate and hyaluronic acid and a decrease in chondroitin 6-sulfate and total uronic acid concentration, with only slight changes in chondroitin 4-sulfate and keratan sulfate compared with normal cartilage.

https://www.tandfonline.com/doi/pdf/10.3109/17453678909150084

Olsen Eb

Papers

Glycosaminoglycans in patellar cartilage