Central Nervous System Xanthoma Disseminatum: Response to 2CdA in an Adolescent.

Xanthoma disseminatum is a normolipemic non-Langerhans cell histiocytosis characterized by red-brown rubbery papules of the skin which coalesce into plaque-like lesions with symmetric involvement of face, flexor, and intertriginous areas. Less commonly, xanthoma disseminatum may affect mucosal linings, abdominal organs, and the central nervous system, leading to endocrinopathies. We report a 12-year-old adolescent with mucosal, central nervous system, and painful cutaneous lesions, further complicated by diabetes insipidus and amenorrhea.

Genetic Mutations Underlying Phenotypic Plasticity in Basosquamous Carcinoma.

Basosquamous carcinoma (BSC) is an aggressive skin neoplasm with the features of both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). While genetic drivers of BCC and SCC development have been extensively characterized, BSC has not been well studied, and it remains unclear whether these tumors originally derive from BCC or SCC. In addition, it is unknown which molecular pathways mediate the reprogramming of tumor keratinocytes toward basaloid or squamatized phenotypes.

Alopecia and Associated Toxic Agents: A Systematic Review.

Importance/objective: There are a number of toxic agents that can cause alopecia. In this review we summarize the known substances that cause alopecia as one of the clinical signs of overdose or toxicity.

Evidence Review: A search was conducted using PubMed, EMBASE, and Cochrane for studies describing hair loss of any type as a result of exposure to or ingestion of a toxic agent.

Genomic Stability in Syndromic Basal Cell Carcinoma.

Basal cell cancers (BCCs) are characterized by upregulation of Hedgehog pathway through loss of PTCH1 or activation of SMO, and SMO inhibitors, such as vismodegib, are effective therapies for advanced BCCs. Although most BCCs are sporadic, rare individuals with basal cell nevus syndrome (BCNS) harbor germline defects in PTCH1 and develop up to hundreds of tumors that are histopathologically indistinguishable from sporadic BCCs. Interestingly, BCNS-BCCs are more responsive to SMO inhibitors than sporadic BCCs, with minimal development of resistance.

Stratum corneum reservoir as a predictive method for in vitro percutaneous absorption.

Interaction between drug and proteins and lipids in stratum corneum (SC) is an important pharmacokinetic parameter in early steps of absorption. Previous in vivo studies showed that the total amount of compound, regardless of properties, penetrating over a 96 h period could be predicted by the amount present in SC 30 min after application by a linear relationship. Validating this linear relationship through in vitro study would facilitate testing of transdermal drug delivery platforms.

Transungual delivery of ketoconazole using novel lacquer formulation.

Onychomycosis, a common fungal infection of the nail, can have a substantial impact on quality of life. The success of topical therapy for onychomycosis depends on effective penetration, which can be enhanced using an appropriate delivery method. This study evaluated the effectiveness of a novel topical lacquer on enhancing [(14)C]-ketoconazole penetration by comparing nail absorption, nail distribution, and nail penetration of [(14)C]-ketoconazole dissolved in the novel lacquer versus a commercial ketoconazole cream.

Role of partition coefficients in determining the percutaneous penetration of salicylic acid and formaldehyde under varying occlusion durations.

Context: Occlusion is widely utilized to enhance the percutaneous penetration of applied drugs in clinical practice; however, occlusion does not increase the penetration of all chemicals.

Objective: This study determines: (1) whether occlusion enhances the percutaneous penetration of the lipophilic salicylic acid or the hydrophilic formaldehyde when compared to non-occlusion, (2) evaluate whether occlusion duration affects the penetration of compounds and (3) establish to what extent occlusive films in clinical practice interact with topically-applied chemicals and possibly hinder penetration.

Materials And Methods: Separately, single doses of [14C]-formaldehyde and [14C]-salicylic acid were applied onto human skin overlying diffusion cells under non-occlusion as well as various occlusive time periods (1, 4 and 8 h).

Skin lesion metrics: role of photography in acne.

Accurate assessment of acne severity is essential for determining the appropriate treatment required. This paper reviews photographic methods for such assessment. Literature included met the following criteria: proposed photographic standards to assess acne, evaluated such standards, or offered photographic methods to improve visualization and assessment.

Percutaneous absorption in diseased skin: an overview.

The stratum corneum's (SC) functions include protection from external hazardous environments, prevention of water loss and regulation of body temperature. While intact skin absorption studies are abundant, studies on compromised skin permeability are less common, although products are often used to treat affected skin. We reviewed literature on percutaneous absorption through abnormal skin models.

Towards a perfect vehicle(s) for diagnostic patch testing: an overview.

The correct selection of vehicles for patch testing is crucial in evaluating suspected allergic contact dermatitis. We reviewed literature by searching Pubmed and Embase for the years 1971-2011 utilizing the subjects "vehicle," "allergic contact dermatitis" and "patch test" for advances in knowledge of vehicles." A universal optimal vehicle more efficient than petrolatum remains undiscovered.