Collagen preparation

The intrinsic viscosity of the collagen preparation supports the notion that a significant fraction of the adsorbed collagen is present in the form of the dimer, i.e. of two triple helical, 3000 A long cylinders, flexibly joined together. Whereas at 7.7°C these dimers may mainly be folded and have two of the non-helical ends on the surface. It is conceivable that one end is permitted to lift off at the higher temperature and that the doubling in thickness is thus produced by a mechanism not related to a BET-like multilayer formation. 

Figure 3. Sorption of fS-galactosidase fE. coli Km) by collagen preparations at different levels of lysyl group modification...

Figure 4. Sorption of p-galactosidase by collagen preparations (samples as in Figure 2) at different degrees of lysine content as a double reciprocal plot for control, Ac — 14 X 10 6 for 15% modification, A0 — 0.53 X 10 6 for 30% modification, Ac = 0.41 X 10 6 for upper curve, A = 0.18 X 10 6 mol/g collagen,...

Figure 5. Internal reflection IR spectra of the surface zones of films of a highly purified rat skin collagen sample (top) ana a more heterogeneous collagen preparation from bovine Achilles tendon collagen (bottom)...

As soon as glial cells are ready (3 weeks), coat 6-well-plate filters on the upper side with rat tail collagen prepared by a modification of the method of Bornstein [25], Otherwise, rat tail collagen is commercially available (see References list in Sect. 3). 

Prolyl hydroxylase from the earthworm requires the same co-factors as the animal enzymes, but it has a different substrate specificity. It requires that the glycine residue precede the proline rather than follow it. Thus, the peptide (Gly-Pro-Ala)n is a substrate for earthworm prolyl hydroxylase but not for mammalian and bird enzymes (132). Prolyl hydroxylase from carrots appears to be very similar in co-factor requirements and specificity to that of the animal enzymes (119). The plant enzyme could hydroxylate collagen prepared from chick-embryo tibias and the animal enzyme could hydroxylate the unhydroxylated plant substrate dehydroxyextensin. 

Figs. 21 through 28. Electron micrographs of collagenous preparations as follows ... 

Collagen Preparation 1. Tissue-culture-grade water (Cambrex). 2. Powder OptiMEM made to lOx OptiMEM (Invitrogen). 3. Tissue-culture-grade sterile 7.5% sodium bicarbonate solution (Sigma). 

Besides collagen in a solid form, one of the most commercially prosperous uses of collagen has been the subcutaneous injection of soluble collagen for the repair of dermatological defects. In other medical applications, similar collagen preparations have been injected successfully, like the treatment of vocal fold immobility and urinary incontinence. ... 

Also, an increased incidence of cell-mediated and humoral immunity to various collagens has been found in systemic connective tissue disease such as rheumatoid arthritis, juvenile rheumatoid arthritis, and progressive systemic sclerosis (scleroderma). Patients with these diseases may thus have an increased susceptibility to hypersensitivity responses and/or accelerated clearance of their implants w hen injected with bovine dermal collagen preparations. Therefore, caution should be used when treating tliese patients including consideration for multiple skin lesions. 

M. Minabe, A. Uematsu, K. Nishijima, E. Tomomatsu, T. Tamura, T. Hori, T. Umemoto, and T. Hino, Apphcation of local drug delivery system to periodontal therapy. Development of collagen preparations with immobiflzed tetracycflne,/. Periodontol., 60 (2), 113-117,1989. 

Results are expressed as average 1 standard deviation 82A and 85A represent different collagen preparations... 

Gelinsky M, Welzel PB, Simon P, Bernhardt A, Konig U. Porous three-dimensional scaffolds made of mineralised collagen preparation and properties of a biomimetic nanocomposite material for tissue engineering of bone. Chem Eng J 2008 137(l) 84-96. 

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