Eric F. Bernstein

Pulsed dye laser therapy for sun damaged skin

The objective of this study was to evaluate the effectiveness of the pulsed dye laser (585 nm, 450 ms) in the treatment of sun induced wrinkles.

Chronic sun exposure alters both the content and distribution of dermal glycosaminoglycans

Summary Chronic sun exposure leads to structural and functional alterations in exposed skin. Photoageing is a process distinct from the changes taking place due to chronological ageing. Unique alterations in the dermal extracellular matrix occur as a result of photoageing and are responsible for many of these physiological changes taking place in sun‐damaged skin. Accompanying the deposition of abnormal elastic tissue, or solar elastosis, are significant alterations in dermal glycosaminoglycans (GAGs). Accumulation of GAGs as a result of photoageing as demonstrated in both humans and animal models of photoageing seems almost paradoxical in view of the large amounts of GAGs present in the skin of newborns, making their skin well hydrated and supple, in sharp contrast to the weathered appearance of photoaged skin. We investigate the relative GAG content of photoaged skin using immunoperoxidase stains specific for hyaluronic acid and chondroitin sulphate, and determine the location of these GAGs using confocal laser scanning microscopy. Our results demonstrate significant increases in GAG staining in sun‐damaged vs. sun‐protected skin from the same individuals, as measured by computer‐based image analysis. Furthermore, confocal laser scanning microscopy reveals that the increased dermal GAGs in sun‐damaged skin are deposited on the elastotic material of the superficial dermis of photodamaged skin, and not between collagen and elastic fibres as in normal skin. The abnormal location of GAGs on these fibres may explain the apparent paradoxical weathered appearance of photodamaged skin despite increased GAGs.

Evaluation of sunscreens with various sun protection factors in a new transgenic mouse model of cutaneous photoaging that measures elastin promoter activation

BACKGROUND Long-term sun exposure can cause major alterations in the papillary dermis, resulting in the deposition of massive amounts of abnormal elastic material, termed solar elastosis. Previous work has demonstrated that this type of photodamage is accompanied by an increase in elastin and fibrillin messenger RNAs and elastin promoter activity. OBJECTIVE Our purpose was to develop a rapid and sensitive in vivo method for evaluating compounds offering protection against cutaneous photodamage. METHODS Using a line of transgenic mice that expresses the human elastin promoter linked to a chloramphenicol acetyltransferase reporter gene, we applied sunscreens with various sun protection factors to 5-day-old mice followed by 30 minimal erythema doses of solar simulating radiation for three consecutive days. RESULTS Solar simulating radiation alone resulted in a fivefold increase in elastin promoter activity. Sun protection factors of 2, 4, 8, and 15 yielded a reduction in promoter activity by 2.8%, 42.5%, 58.1%, and 70.3%, respectively. CONCLUSION These results confirm the use of this system as a rapid and sensitive in vivo model for evaluating compounds that protect against photodamage.

8-Methoxypsoralen and Ultraviolet A Radiation Activate the Human Elastin Promoter in Transgenic Mice: In vivo and in vitro Evidence for Gene Induction

Treatment of skin diseases with the combination of 8‐methoxypsoralen and ultraviolet A radiation (PUVA) results in clinical alterations in treated skin that resemble those observed in chronically photodamaged skin. The PUVA‐treated patients develop nonmelanoma skin cancers, pigmentary alterations and wrinkling characteristic of sun‐induced changes. The major alteration in the dermis of sun‐damaged skin is the deposition of abnormal elastic fibers, termed solar elastosis. Up‐regulation of elastin promoter activity in dermal fibroblasts explains the excess elastic tissue but not the reason for the aberrant morphology of the elastotic material. In order to study photoaging in an experimental system, we utilized a transgenic mouse line that expresses the human elastin promoter/chloramphenicol acetyltransferase construct in a tissue‐specific and developmentally regulated manner. Although UVB radiation has been demonstrated to increase promoter activity in vitro, UVA fails to demonstrate a similar effect at the doses utilized. In this study, we demonstrate the ability of PUVA treatment to up‐re‐gulate elastin promoter activity both in vitro and in vivo. These data help to explain the development of photoaging in sun‐protected PUVA‐treated skin. We attribute the up‐regulation of elastin promoter activity in response to PUVA to the formation of DNA photoadducts, which do not occur in response to UVA radiation alone.

A novel dual‐wavelength, Nd:YAG, picosecond‐domain laser safely and effectively removes multicolor tattoos

Although nanosecond‐domain lasers have been the mainstay of laser tattoo removal for decades, recent disruptive innovations in laser design have introduced a new class of commercial Q‐switched lasers that generate picosecond‐domain pulses.

The nitroxide Tempol affords protection against ultraviolet radiation in a transgenic murine fibroblast culture model of cutaneous photoaging

Abstract: The generation of reactive oxygen species is among the various mechanisms by which ultraviolet radiation damages skin. Tempol, a superoxide dismutase analogue which readily penetrates cell membranes when administered exogenously, has been shown to provide protection against some forms of oxygen‐dependent damage. In this study, we measured the ability of Tempol to protect against ultraviolet A‐ and ultraviolet B‐induced damage, using a previously described transgenic mouse model of cutaneous photoaging. The ability of Tempol to prevent ultraviolet radiation‐induced elastin promoter activation was determined in vitro. Tempol provided over 50% protection against ultraviolet B and over 70% protection against ultraviolet A as measured in our in vitro system. These results demonstrate the ability of the superoxide dismutase mimic, Tempol, to protect against ultraviolet induced elastin promoter activation. This compound could be a useful pharmacological agent to prevent cutaneous photoaging.

Treatment of acne scarring with a novel fractionated, dual‐wavelength, picosecond‐domain laser incorporating a novel holographic beam‐splitter

Fractional treatment with a dual wavelength 1,064 and 532 nm picosecond‐domain laser, delivering a 10 × 10 array of highly focused beamlets via a holographic optic, was investigated for the treatment of acne scars.

A widespread allergic reaction to black tattoo ink caused by laser treatment

This is the first reported case of a local and widespread reaction in a 39 year old woman, to black tattoo ink, induced by Q‐switched laser treatment.

A continuously variable beam‐diameter, high‐fluence, Q‐switched Nd:YAG laser for tattoo removal: Comparison of the maximum beam diameter to a standard 4‐mm‐diameter treatment beam

Laser beam diameter affects the depth of laser penetration. Q‐switched lasers tend to have smaller maximum spot sizes than other dermatologic lasers, making beam diameter a potentially more significant factor in treatment outcomes.

Treatment of spider veins of the lower extremity with a novel 532 nm KTP laser

This study investigated a novel, high‐power, 532 nm frequency‐doubled Nd:YAG, KTP laser with contact cooling for the treatment of spider veins of the lower extremities.