Collagen Scar Formation Research Articles

Serum galactosylhydroxylysyl glucosyltransferase in acute myocardial infarction and during subsequent collagen scar formation.

Changes in serum galactosylhydroxylysyl glucosyltransferase, an enzyme catalysing one of the intracellular post-translational modifications in collagen biosynthesis, were studied in twenty-four patients with acute myocardial infarction. The enzyme activity was monitored for 18 days from the onset of infarction, and at least a two-peaked pattern was observed. The first peak corresponded to the stage of acute myocardial injury, there being a highly significant correlation between the maximal values for serum glucosyltransferase and alpha-hydroxybutyrate dehydrogenase. An average decreasing in serum glucosyltransferase activity of 41%, was noted during the following 24 h. A new gradual rise in serum glucosyltransferase activity, interpreted as indicating myocardial collagen scar formation, was observed 5 days after the onset of infarction, when the serum enzyme activities indicating myocardial injury had already declined. The average daily values for serum glucosyltransferase between 6 and 18 days correlated highly significantly with the maximal value for serum alpha-hydroxybutyrate dehydrogenase, which serves as a relative estimate of the size of the original myocardial infarction area. The data further suggest that certain other factors including heart failure and/or various drug treatments may also affect the magnitude of this second peak.

Study of elastolytic activity Propionibacterium acnes and Staphylococcus epidermis in acne vulgaris and in normal skin

Histopathological sections of anetoderma-like scars from 10 patients with acne vulgaris showed a selective absence of elastic fibers around pilosebaceous follicles. This finding is similar to the histologic changes of "perifollicular elastolysis" reported by Varadi. Bacteria isolated by anaerobic and aerobic cultures of swabs of the skin surface and pus of these 10 patients, 12 others with active acne vulgaris and 8 normal subjects were studied with particular attention to Staphylococcus epidermis and Propionibacterium acnes. These organisms were analysed for production of an elastolytic enzyme which might play a role in the observed selective loss of elastic fibers. No elastolytic activity was produced by S. epidermidis or P. acnes isolated from any of these individuals. Thus, we cannot attribute the perifollicular loss of elastic fibers in acne scarring to an elastase produced by organisms. The observed absence of elastic fibers might result from tissue necrosis produced by leukocytes during the inflammatory phase, followed by collagenous scar formation without regeneration of elastic fibers.

Experimental use of cultured cerebellar cortical tissue to inhibit the collagenous scar following spinal cord transection.

✓ Two types of barrier to axonal regeneration in the spinal cord were found in experimental spinal cord transection in dogs. One was an astroglial scar formed within the spinal cord, and the other a collagenous scar in the gap between proximal and distal stumps. Autogeneous cultured cerebellar cortical slices transplanted into the space produced by cord transection in adult dogs inhibited collagenous scar formation and converted the gap into a spongy structure. The astroglial scar within the spinal cord remained unchanged. Conversely, transplantation of noncultured cortical slices as a control study enhanced formation of the collagenous scar.