Biological time / by Lecomte du Noüy.

  • Lecomte du Noüy, Pierre, 1883-1947.
Date:
1936
Catalogue details

Licence: In copyright

Credit: Biological time / by Lecomte du Noüy. Source: Wellcome Collection.

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    rectangular aspect (Figs. 2 and 3). ‘This proves that contraction stopped at the level of the graft while it continued to act everywhere else.’ In another experiment, he stimulated the epithelization of a large square wound which showed no trace of epithelium in the lower part by grafting a small piece of epithelium. It is a well-established fact that a living graft increases the production of epithelial cells. It was then observed (Figs. 4, 5? and 6) that the distance between the lines tattooed in India CONTRACTION ink on the edges of the wound, decreased in the lower part (presence of granulations) while it remained constant in the upper part (absence of granulations). The wound became trapezoidal (Fig. 5) and when totally healed resumed its primitive shape. It is therefore certain that epithelization inhibits the function of contraction of the granulations. When epithelization is precocious, the scar is large and thin. When it is slow, the contraction is stronger and the scar is thick and comparatively smaller. The preparation of the surface of the wound for the migra- tion of the epithelial cells is also a function of the granulations. But it seems that their principal role is to bring the edges of the wound within a certain distance of each other, about 10 or 15 millimetres in a dog. This may be deduced from the fact that a wound which is 10 millimetres broad, no longer contracts. The contraction becomes useless because at a distance of 10 millimetres the secondary mechanism, namely epithelization, functions easily, as we will show farther on.