Burn Infliction Research Articles

Differentiation of inflicted dermal burns by high-frequency ultrasound scanning: An animal experiment.

The depth of experimentally inflicted superficial/partial dermal burns and deep dermal burns were non-invasively evaluated using a 30 MHz B-mode high-frequency ultrasound scanner. Superficial and deep burns were produced in 10 Harley female albino guinea pigs. Ultrasound scanning was performed immediately after, and 24, 48, 72 and 96 postbum. Specimens for histology were obtained after 72 h. The echo reflection at the dermis-subcutaneous interface was easily defined 2 days after burn infliction in all superficial/partial dermal burns, whereas it was disturbed and not detected in any deep dermal burn. It is concluded from our study that the ultrasonography of the deep dermis, especially the dermis-subcutaneous interface, is of major importance in the diagnostic and prognostic evaluations of burns.

Estimation of local vital reactions in severely burned tissues of guinea pig skin using C3a or C3a desArg as a marker

We observed changes in levels of anaphylatoxin C3a and/or its desArg (C3a/C3a desArg) peptides in the local site of severely burned skin tissues of guinea pigs using immuno-Western blotting methods. The C3a/C3a desArg peptides, which were probably generated during complement activation, were detected at significant levels from 30 min to 72 h following burn injury in an area limited to 3 mm from the wound edge. Levels of these peptides showed a tendency to be highest in that area 24 h after burn infliction. In postmortem injuries, C3a/C3a desArg peptides could not be detected. These peptides were detected in antemortem wounds up to at least 2 days at 22 degrees C and up to 3 days at 4 degrees C after death, although decreases in levels were found. Lower concentrations of these peptides were also found in postmortem burns in which postmortem hypostasis appeared strongly. These results suggest that, except for injuries of the area with obvious postmortem hypostasis, detection of C3a/C3a desArg can be useful for estimation of vital reactions in many kinds of wounds during inflammation.

The effect of aging on cutaneous lipid peroxide levels and superoxide dismutase activity in guinea pigs and patients with burns

Cutaneous lipid peroxide levels and superoxide dismutase (SOD) activity in non-aged and aged guinea pigs were measured between 15 min and 7 days after experimental infliction of burns. Skin burns on non-aged and aged patients were also subjected to these assays. In non-aged guinea pig skin burns, lipid peroxide levels increased from 24 hr to the fourth day after the burn infliction, shile SOD activity did not increase but showed a slight decrease 12 hr and 24 hr post-burn. On the other hand, while the aged group showed a more increase in skin lipid peroxide levels compared to that seen in non-aged mice, skin SOD activity began to decrease from 30 min post-burn, the maximum decrease being reached on the second day. The activity did not return to normal by the 7rh day. In non-aged patients skin burns showed increases in both lipid peroxide levels and SOD activity, while in aged patients, though they showed a marked increase in lipid peroxide levels, SOD activity remained unchanged. The present study indicated that, although in our recent study, skin SOD activity of healthy elderly people was found to be comparable to that in non-aged individuals, the capacity for induction of SOD activity under oxygen stress differed with age in both guinea pig and human burn sufferers. Furthermore, this induction capacity seemed to vary from species to species.

A new optical method for experimental burn infliction

A new optical method for experimental burn infliction

Characteristics of the skin lactate dehydrogenase isozyme spectrum after thermal injuries

Activity of lactate dehydrogenase (LD) and its isozymes in the injured zone and in adjacent areas of the skin was investigated at various times after infliction of burns in rats. On the 1st–8th day after burning total LD activity was reduced in the zone of the scab and in the underlying tissues by 70–80% and in the border and intact skin by 50%. These changes were accompanied by changes in the LD isozyme spectrum in the injured tissue: On the 1st day the activity of fraction 5 was sharply increased and activity of fractions 2 and 3 reduced; by the 8th day, on the other hand, some decrease in activity of fraction 5 and an increase in activity of fractions 2 and 3 were observed. By the 14th–22nd day after burning total LD activity remained low, the LD isozyme spectrum in the border and scab was largely restored to normal, whereas in the underlying tissue changes in the relative proportions of LD isozymes were still present (a decrease in activity of fractions 1–3 and an increase in activity of fraction 5).

The mitotic activity of the cornea in mice after infliction of a burn at different times of day

The 24-hour rhythm of cellular division is preserved in symmetrical cornea by inflicting corneal burns in the morning. However, the average values of mitotic coefficients during the whole experiment appear to be lower than in the cornea of normal animals. The infliction of burn in the evening has no effect on the character of the 24 hour rhythm. However the general level of mitotic activity is much higher. A stable depression of the tempo of cellular division was noted in the injured cornea.