Differences In Skin Thickness Research Articles

Skin thickness in cutis verticis gyrata and mental retardation syndrome.

To study the distribution of the skin involvement in the cutis verticis gyrata and mental retardation (CVG-MR) syndrome skin thickness was determined radiographically on the flexor aspect of the forearm of ten patients with this syndrome. The skin of patients was thicker than that of normal controls but the difference was quite significant (1.4 +/- 0.4 mm versus 1.1 +/- 0.2 mm; p less than 0.05). When the analysis was applied to males only, the difference was statistically significant (1.5 +/- 0.3 versus 1.1 +/- 0.2 mm; p less than 0.01). There was no difference in skin thickness between the primary and miscellaneous forms of the syndrome. The findings suggest generalised skin involvement in the CVG-MR syndrome.

Strength development of skin incisions in young and old rats

International Abstracts of Plastic and Reconstructive Surgery: Congenital Anomalies: Wound Healing: PDF Only

Strength development of skin incisions in young and old rats.

Studies of strength development in standardized skin incisions in young and old rats have shown that the breaking load is significantly higher in young animals than in old animals at days 4 and 21 after wound infliction, but not different at days 7 and 14. Skin was, on average, 40% thicker in the old animals than in the young. Breaking strength values (breaking load per unit cross-sectional wound area) were found to be lower in old animals than in young animals at all postsurgical intervals studied. This strongly suggests that the capacity for repair and regeneration is decreased in old animals. Previous studies claiming that strength development is unimpaired in wounds in old animals have not taken into consideration differences in skin thickness (wound area) at different ages.

The significance of the thickness of cattle skin

The skin is thin at birth. Seasonal variations and changes in the plane of nutrition affect the skin thickness. The differences in skin thickness between breeds of both B. taurus and B. indicus species, are highly significant. Both thin and relatively thick hides may be associated with any combination of milk and beef, early and late maturity, temperate and tropical type cattle.

Tolerance of Gaspe fishermen to cold water.

A group of Gaspé fishermen used to cold water immersion and control subjects from the same vicinity were studied to determine if the fishermen's hands were adapted to cold. With one hand immersed in cold water, the pressor response was greater in the control subjects; the fishermen maintained a higher finger temperature and complained less of pain; heat flow from the fishermen's hands was greater than in the control group; finger numbness as measured by a modification of Mackworth's V-test was variable and not significantly different in the two groups. Skin biopsies showed no difference in skin thickness or cell size but there was a significantly greater number of mast cells in the fishermen's skin. The differences between the fishermen and the control subjects may be related to repeated cold exposure. Submitted on June 7, 1960

Hypothermic facilitation of retrograde V-A conduction.

A group of Gaspé fishermen used to cold water immersion and control subjects from the same vicinity were studied to determine if the fishermen's hands were adapted to cold. With one hand immersed in cold water, the pressor response was greater in the control subjects; the fishermen maintained a higher finger temperature and complained less of pain; heat flow from the fishermen's hands was greater than in the control group; finger numbness as measured by a modification of Mackworth' V-test was variable and not significantly different in the two groups. Skin biopsies showed no difference in skin thickness or cell size but there was a significantly greater number of mast cells in the fishermen's skin. The differences between the fishermen and the control subjects may be related to repeated cold exposure. Submitted on June 7, 1960

Nomograms for the solution of spherical triangles

Reliable models for the determination of skin penetration and permeation are important for the development of new drugs and formulations. The intention of our study was to develop a skin penetration model which (1) is viable and well supplied with nutrients during the period of the experiment (2) is mimicking human skin as far as possible, but still is independent from the problems of supply and heterogeneity, (3) can give information about the penetration into different compartments of the skin and (4) considers specific inter-individual differences in skin thickness. In addition, it should be quick and inexpensive (5) and without ethical implications (6). Using a chemically divers set of four topically approved active pharmaceutical ingredients (APIs), namely diclofenac, metronidazole, tazarotene, and terbinafine, we demonstrated that the model allows reliable determination of drug concentrations in different layers of the viable epidermis and dermis. For APIs susceptible for skin metabolism, the extent of metabolic transformation in epidermis and dermis can be monitored. Furthermore, a high degree of accordance in the ability for discrimination of skin concentrations of the substances in different layers was found in models derived from porcine and human skin. Viability, proliferation, differentiation and markers for skin barrier function were surveyed in the model. This model, which we call ‘Hamburg model of skin penetration’ is particularly suited to support a rational ranking and selection of dermatological formulations within drug development projects.