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D J Buttle

Publications and source records attributed to D J Buttle.

77 records · Page 5Linked to original sources

Effect of X-ray contrast media on the action of chymopapain on the intervertebral disc: an in vitro study of cartilage degradation.

A representative selection of X-ray contrast media was tested for their effects on the action of chymopapain on cartilage proteoglycan in an in-vitro test system. Inhibition of the action of chymopapain was detected only at high concentrations of contrast media, and was more marked with ionic contrast media than with non-ionic media. A dose-response curve for the release of glycosaminoglycan by chymopapain was linear when the amount of enzyme was plotted on a logarithmic scale against glycosaminoglycan release. In view of our results, we suggest that there is no need for a delay between injection of contrast medium and enzyme, contrary to the instructions of the distributors of chymopapain, if small amounts of a non-ionic contrast medium are used.

Animals↗

Comparative studies of collagen lattice contraction utilizing a normal and a transformed cell line.

Differences between the behavior of cultured rat skin fibroblasts and that of a line of transformed rat sarcoma cells incorporated into a polymerized collagen lattice were examined. Fibroblast-populated collagen lattices (FPCL) were manufactured. Within 24 to 48 hr after manufacture, both cell lines reduced lattice size by a process known as lattice contraction. Contraction occurred more rapidly in both cell lines when the media were supplemented with 25% serum rather than the usual concentration of 10% serum. Similar growth patterns were observed with transformed cells within collagen lattices and on plastic surfaces. Normal rat fibroblasts were found to contract lattices faster than transformed cells. At the end of a 2-week period, the final contracted size of the transformed cell lattice was the same as that of normal cell lattices. The cellular density of transformed cells within the FPCL was eight times greater than that of FPCL made with normal rat cells. Normal rat fibroblasts elongated and flattened more, and organized the collagen matrix to a greater degree, than did transformed cells. In this instance, therefore, lattice contraction was shown to be linked more to the process of fibroblast elongation and collagen fiber organization than to cell number or density.

Animals↗

Epidermolysis bullosa dystrophica recessive fibroblasts altered behavior within a collagen matrix.

Normal human fibroblasts incorporated into a collagen lattice reduce the size of that lattice over a period of time. Lattice size reduction or lattice contraction is directly related to initial cell number. When equal numbers of fibroblasts derived from patients with epidermolysis bullosa dystrophica recessive, (EBdr), are used, there is delayed lattice contraction. The EBdr fibroblasts have an altered cellular shape, when compared to normal cells, in that the EBdr cells fail to flatten out and elongate, but do attach to collagen fibers like normal fibroblasts. EBdr fibroblasts maintain a rounded shape with numerous filopodia radiating from the cell periphery and such filopodia are attached to the collagen fibers of the lattice. In monolayer tissue culture on glass surfaces, EBdr fibroblasts are three times more likely to grow over neighboring fibroblasts. EBdr cell filopodia structures are attached to the cell surfaces lying beneath them, which demonstrates another condition of altered anchorage attachment of EBdr fibroblasts.

Cell Division↗

Development and use of a living skin equivalent.

We have developed a living skin equivalent, which serves as a skin substitute in experimental animals. On application it is rapidly vascularized, it inhibits wound contraction, and it is immunologically tolerated and persists for as long as it is allowed to remain in place. It comes to resemble normal skin, although it lacks secondary derivatives, the cells for which may in time be available for incorporation into the fabricated tissue.

Animals↗