R Vasselet | PubMed Health

PubMed1990

Localized scleroderma--response to 1,25-dihydroxyvitamin D3.

1,25-Dihydroxyvitamin D3 [1,25(OH)2 D3] may be an immunomodulatory drug which could have a role in controlling collagen deposition, and inducing reversal of fibrosis in some tissues. These observations prompted a study of the possible use of this hormone for the treatment of scleroderma. A 35-year-old woman, who had been suffering from localized scleroderma for 2 years, was given oral 1,25(OH)2 D3 for 6 months. The effects of the treatment were evaluated using clinical and physical measurements (skin thickness, extensibility properties of the skin). The evolution of the patient's condition during the 6-month therapy suggests that 1,25(OH)2 D3 is beneficial in localized scleroderma. The mechanisms of action are discussed in relation to the literature, which suggests both immunoregulatory and inhibitory effects on fibroblast growth.

Adult↗

PubMed1989

Age-related mechanical properties of human skin: an in vivo study.

We have investigated in vivo how various viscoelastic parameters that describe the mechanical properties of the human skin may vary with age. Accordingly, we have used a mechanical device that records the torsional extensibility of the skin. When submitted to a low torque, the time-response curve of the skin affords the determination of the immediate extensibility (UE), the immediate recovery (UR), the viscoelastic part of the deformation (UV), the elastic recovery (UR/UE), and the creep relaxation time (tau). Because the skin thickness varies with age and primarily governs the mechanical properties, it was measured through an ultrasound technique at the same sites (forearm) where the torque was applied. The results show that the skin maintains its thickness and extensibility up to the seventh decade as opposed to its elasticity or recovery capacities, which decrease from an early age. The viscous part of the deformation is constant through life, whereas the creep relaxation time decreases linearily with age. Except for skin thickness, no differences in these parameters between men and women were detected. The significance of these results are discussed in terms of structure alterations. The determination of the elastic recovery (UR/UE) appears to be a parameter of choice for illustrating skin aging.

Adolescent↗