Glycosaminoglycans variable

Unfractionated heparin (UFH) is a heterogeneous mixture of sulfated glycosaminoglycans of variable lengths and pharmacologic properties. The molecular weight of these molecules ranges from 3,000 to 30,000 daltons (mean 15,000 daltons). 

Keratan sulfate consists of the disaccharide, iV-acetyl-lactosamine, linked /3-(1 3) to the D-galactopyranose residue of the next iV-acetyl-lactosamine unit. Keratan sulfate is the most heterogeneous of the glycosaminoglycans, with variable sulfate content linked to C-4 or C-6 of the D-galactop)Tanose residue in lactosamine, and small amounts of L-fucose (6-deoxy-L-galactose), D-mannose, and iV-acetyl-neuraminic acid residues [93] (also see Sects. 10.2 and O 14 on the occurrence of iV-acetyl-D-neuraminic acid and L-fucose in other systems). Keratan sulfate is found in the cornea, on the surfaces of erythrocytes, in cartilage, and in bone. 

Glycosaminoglycan (and range of molecular weight) Amino Sugar Uronic Acid Type of Sulfate Linkage (extent of sulfation is variable) Tissue Distribution... 

Each of these methods samples only cells and soluble inflammatory products in the airspaces. Cells in the vascular and interstitial compartments are not recoverable, and there has been debate about whether adherence characteristics of air space cells modify cellular recovery. Neither method is likely to recover proteins that precipitate in the airspaces, and neither can sample precisely inflammatory products such as chemokines that bind to glycosaminoglycans and other structures in the lungs. Nevertheless, the measurements of cell populations and inflammatory products in BAL and edema fluid provide an estimate of the amounts that are actually present in the air space compartment of the lungs. The inability to accurately sample the total concentrations of specific inflammatory products in the lungs may account for some of the variability seen in clinical studies, and some of the difficulties that have been encountered in correlating BAL and edema fluid findings with clinical variables. 

The Sly syndrome is similar in clinical features to that of the mucopolysaccharidosis type I disorders. Patients have unusual facies, depressed nasal bridge, prominent maxillae, and anteverted nostrils. By 2.5 years of age, developmental retardation is observed. Several cases of jff-glucuronidase deficiency have been reported in newborns with non-immune hydrops fetalis. Urinary excretion of glycosaminoglycans are elevated and variable [1]. The prevalence of Sly syndrome is estimated at 1 in 2,111,000, the rarest of all mucopolysaccharidoses [2]. 

Carreno, M.R., Muniz, O.E., Howell, D.S. (1986) The effect of glycosaminoglycan polysulfuric acid ester on articular cartilage in experimental osteoarthritis effect on morphological variables of disease severity. Journal of Rheumatology, 13,490-497. 

Keratan sulfate is the most heterogeneous of the glycosaminoglycans in that the sulfate content is variable, and it contains small amounts of L-fucose, D-mannose, and A-acetyl-D-neuraminic acid residues [130]. Keratan sulfate proteoglycan is found in the cornea, on the surface of erythrocytes, in cartilage, and in bone. 

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