This article contains large chunks of text copied from the text book “Wound healing: biochemical & clinical aspects” edited by Kelman Cohen et al. and published by W.B. Saunders Company in 1992. This book is available in the HKU Dental Library.
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.....with the marginal cells at
the advancing front being the active motile
cells, while the cells behind the margins are passively dragged along
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the cells at the margin of the
moving sheet appeared to be actively motile
while the cells behind (or above, in a stratified layer) the marginal cells were passively dragged along
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It is more
difficult to study mammalian cutaneous wound closure directly because of the
thickness and opacity of the dermis. Moreover, the migrating epithelial sheet
in the mammalian epidermis is multilayered and thus more complex than those
systems illustrated in the sliding model.
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It is much more
difficult to study mammalian
cutaneous wound
closure directly because of the thickness and opacity of the dermis.
Moreover, the migrating epithelial sheet of mammalian epidermis is
multilayered and thus more complex than those systems illustrating the sliding
model.
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For the repair
of mammalian epidermis, WINTER23 proposed the "leap frog
model" of epidermal sheet movement. This model was deduced from morphological
data at ultrastructural level, which suggested that cells at the migrating
front adhere to the substrate......
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For the
repairing mammalian epidermis, Winter40 proposed the leap frog
model of epidermal sheet movement (Fig. 7- 4). This model was deduced
indirectly from ultrastructural morphological data that suggested that cells
at the migrating front adhere to the substrate.........
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.......
submarginal cells are thus designed to crawl over the newly adherent basal cells in a "leap
frog" fashion
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.......submarginal
cells are conceived to crawl over the newly adherent basal cells in a
"leapfrog" fashion
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What actually
turns on the cellular machinery of movement, be it physical or chemical, is
still not known.
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what actually
"turns on" the cellular machinery of movement, be it physical or
chemical, is still not known.
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Little work has
been done on the cytoskeletal mechanism of epidermal cell motility, but it is
recognised that epidermal cells in all strata of the epidermis contain actin
and the motile machinery probably involves the actin-myosin contractile
system
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Little work has
been done on the cytoskeletal mechanisms of epidermal cell motility, but it
is recognized that epidermal cells in all strata of the epidermis contain
actin and that the motile machinery probably involves the actin-myosin
contractile system.
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A cytoskeletal
model of epidermal cell motility has been proposed by Bereiter-Hahn et al., in which the motive
force is generated by directed contractions of the actin filaments in
the cell body, forcing the cytoplasm .....
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A cytoskeletal
model of epidermal cell motility has been proposed by Bereiter-Hahn and
associates45 in which the motive force is generated by directed
contractions
of the actomyosin system, forcing
cytoplasm
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It is generally felt that a free edge is
all epithelium needs to initiate movement....
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It is generally
held that a free edge is all epithelium needs to initiate movement.
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However, this
concept may be an oversimplification since epidermal cells will not migrate in cell
culture unless the substratum is optimal even though the epidermal cells have
a free edge...
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However, that
concept may be too simple since primary epidermal cells not adapted to culture will not spread in tissue culture unless the substratum is optimal even though the
cells have a free edge......
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....it appears
likely that a free edge may provide the stimulus for the epithelial cells to
spread, but .....
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....it appears
likely that a free edge may provide the
external stimulus to spread, but ....
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Recent experiments4 support the fact that under certain circumstances,
mesenchymal cells may transform to become part of the regenerating epithelium
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Recent observations suggest, however, that under some
circumstances mesenchymal cells may transform and become part of the
regenerating epithelium;26
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