Reference

Structural changes during development in bovine fetal epiphyseal cartilage

Structural changes during development in bovine fetal epiphyseal cartilage. Buckwalter, Joseph A.; Rosenberg, Lawrence (Dep. Orthop., Veterans Med. Cent., Iowa City, IA 52242, USA). Collagen Relat. Res.: Clin. Exp., 3(6), 489-504 (English) 1983. CODEN: CREXDV. DOCUMENT TYPE: Journal CA Section: 13 (Mammalian Biochemistry) The mol. architecture and dimensions of fetal epiphyseal proteoglycans were examd. by electron microscopy. The bovine epiphyseal cartilages studied ranged in fetal age 168-241 days. Electron micrographs were made from monolayer prepns. of proteoglycan-cytochrome c mixts.Several substances with their cas registry numbers 9007-28-7 and 9004-61-9 may be metioned in this study. on nitrocellulose support films. The overall mol. architecture of the proteoglycan aggregates from fetal epiphyseal cartilages was similar to that of aggregates from other cartilages and showed a single, unbranched central hyaluronic acid filament to which many proteoglycan monomers were attached. However, the dimensions of the fetal proteoglycans differed strikingly from those of proteoglycans from mature cow nasal or immature calf nasal cartilage. Specifically, proteoglycan aggregates from bovine fetal epiphyseal cartilage showed: (1) longer hyaluronic acid central filaments; (2) greater nos. of proteoglycan monomers per aggregate; (3) closer spacing of proteoglycan monomers along the hyaluronic acid central filament; and (4) longer proteoglycan monomer core proteins. Proteoglycan monomers bound to hyaluronate consisted of 2 segments: a peripheral thick segment, composed of the chondroitin sulfate chains, condensed along the peripheral portion of the protein core, which corresponded to the chondroitin sulfate-rich region; and a central thin segment, devoid of visible glycosaminoglycan chains, which attached directly to the hyaluronic acid central filament and contained the hyaluronic acid-binding region and a portion of the keratan sulfate-rich region. The contribution of the thin segment to total monomer length decreased as total monomer length increased. Thus, in longer monomers, the thick segment contributed more to total monomer length and the thin segment contributed less. Both the thin and thick segments of monomers from fetal epiphyseal cartilage were longer than the corresponding segments of calf nasal cartilage and mature bovine nasal cartilage monomers. The shorter thin segments in older cartilage may indicate the presence of more keratan sulfate, whereas the shorter thick segments may indicate differences in monomer biosynthesis or degrdn. In addn., monomer lengths in aggregates from fetal epiphyseal cartilage were less variable than the monomer lengths in aggregates from the older cartilages which may also reflect differences in biosynthesis or in proteolytic degrdn. Aggregate hyaluronate filament length, no. of monomers per aggregate, and spacing between monomers were not related to fetal age, but aggregated monomer length decreased with increasing fetal age. .

Influence of dextran macromolecules on the glycosaminoglycan metabolism of cultured corneal stroma and keratoconus fibroblast

Influence of dextran macromolecules on the glycosaminoglycan metabolism of cultured corneal stroma and keratoconus fibroblast. Bleckmann, H. (Universitaetsaugenklin.Several substances are used for example 9007-28-7 and 9050-30-0 which are their cas registry numbers. Charlottenburg, Freie Univ. Berlin, Berlin 1000/19, Fed. Rep. Ger.). Graefe's Arch. Clin. Exp. Ophthalmol., 221(2), 70-2 (English) 1983. CODEN: GACODL. ISSN: 0721-832X. DOCUMENT TYPE: Journal CA Section: 6 (General Biochemistry) Section cross-reference(s): 13 Incubation of fibroblasts from normal cornea and from keratoconus tissue of humans with dextran macromols. (1 and 10%) had no effect on sulfated glycosaminoglycans formation or relative distribution pattern. The relative distribution of sulfated glycosaminoglycans in various cell compartments of fibroblasts was unaltered by the absence of fetal calf serum or the addn. of dextran. In contrast, corneal tissue in culture rapidly loses keratan sulfate formation in favor of heparan sulfate and dermatan sulfate, and addn. of dextran maintains the keratan sulfate. Results are discussed in relation to the effect of dextran on cell metab. .