Scott B. Phillips

Fluorescence photography in the evaluation of acne

BACKGROUND Quantification of acne remains a challenge. It may be difficult to identify lesions by standard flash photography. Previous studies have shown that foci of light in fluorescence photographs correspond to high protoporphyrin IX production by Propionibacterium acnes in open comedones, follicles, and inflammatory lesions. OBJECTIVE Our purpose was to study the utility of fluorescence photography for evaluation of acne. METHODS Forty subjects with mild to moderate acne vulgaris were randomly selected to apply either clindamycin 1% topical solution or vehicle twice daily. Counts of acne lesions and flash and fluorescence photographs were obtained at baseline, and at 4, 8, and 12 weeks. RESULTS At 12 weeks, the treatment group had a larger percentage change in open comedones, less fluorescence in all areas assessed, and a larger percent decrease in fluorescence than the vehicle group. CONCLUSION Fluorescence photography appears to be a useful tool to chart the course of acne treatment.

Polarized light photography in the evaluation of photoaging

BACKGROUND The clinical characteristics of photodamaged skin, such as coarse and fine wrinkling, sallowness, hyperpigmentation, tactile roughness, laxity, and erythema, are not accurately evaluable from photographic records. OBJECTIVE The purpose of this study was to develop accurate and reproducible photographic techniques that generate an evaluable record of the characteristics of photodamaged skin. METHODS The method used involved illumination and photography through polarizing filters (polarized light photography). RESULTS Polarized light photography generates images that selectively enhance either the surface features or the subsurface features of the skin, providing an accurate and evaluable record for evaluation of photodamaged skin. CONCLUSION Polarized light photography, when coupled with precise framing and mapping, yields an accurate and evaluable record of photodamaged skin.

Polarized light photography enhances visualization of inflammatory lesions of acne vulgaris

BACKGROUND Polarized light photography has been used to selectively differentiate surface from subsurface features of photoaged skin. OBJECTIVE Our purpose was to compare acne assessments obtained from clinical evaluations with assessments from photographs obtained with flash photography and with perpendicular polarized light photography. METHODS Assessments of acne with the Cunliffe scale were made of 32 subjects. Retrospective evaluations of standard and perpendicular polarized light photographs were made in a blinded fashion by a panel of evaluators. RESULTS Visualization of inflammatory acne lesions was enhanced with perpendicular polarized light photography, with clear delineation of erythematous borders. Acne assessments with the use of a Cunliffe scale were significantly higher (p = 0.001) from perpendicular polarized light photographs than for clinical evaluations. CONCLUSION Polarized light photography enhances visualization of inflammatory acne lesions in a manner not possible with conventional flash photographs, permitting accurate evaluation of the extent of disease and the effectiveness of therapy.

A new class of soluble basic protein precursors of the cornified envelope of mammalian epidermis

The cornified envelope has been shown to be formed beneath the plasma membrane as a result of the cross-linking of soluble and membrane-associated precursor proteins by transglutaminase. We have obtained a monoclonal antibody which reacts with the periphery of cells in the upper layers of human epidermis by indirect immunofluorescence (IIF) following immunization of mice with cornified envelopes of cultured human keratinocytes. The antibody also stained the cell peripheries of bovine, rat and mouse epidermis as well as stratified epithelium. Neutral buffer extracts of human cultured keratinocytes and epidermis examined under denaturing conditions contained polypeptides of molecular weight 14,900 and 16,800 which reacted with the antibody, and an additional component of molecular weight 24,800 was found in cultured cells. The polypeptides were shown to have a pI of about 9.0. Under non-denaturing conditions the two lower-molecular-weight polypeptides had an apparent molecular weight of 30,000, while the 24,800 protein had one of 60,000. Incubation of the polypeptides under conditions that activate transglutaminase resulted in a disappearance of the polypeptides or the formation of cross-linked products. Basic polypeptides with somewhat different pI values and molecular weights were identified in neutral buffer extracts of bovine and rat epidermis. The HCE-2 antibody appears to identify a new class of basic protein precursors of mammalian cornified envelope.

The pancornulins: A group of basic low molecular weight proteins in mammalian epidermis and epithelium that may function as cornified envelope precursors

1. A monoclonal antibody (HCE-2) to human epidermal and epithelial cornified envelopes identified a group of soluble basic protein precursors. 2. Using HCE-2, envelope-like staining was observed in the epidermis and stratified squamous epithelium of a number of mammalian species. 3. Basic polypeptides reactive to HCE-2 varied in size and number among the different animals. 4. In those species studied, HCE-2-reactive peptides were substrates for transglutaminase and protease treatment of cornified envelopes released HCE-2-reactive degradation products. 5. These results suggest a new family of proteins in mammalian epidermis that may function as cornified envelope precursors.