An Atypical Presentation of a Rare Disease

A 76-year-old white woman presented for evaluation of asymptomatic skin lesions on her right shin, right buttock, and left arm. All lesions initially underwent slow growth and plateaued and then remained stable in size. A complete review of systems revealed normal results. She had 3 well-demarcated erythematous round plaques ranging from 1.5 to 3 cm, all with a central depression, yellow hue, and prominent telangiectasias (Figs 1 and 2). An excisional biopsy was performed. Histologically, there were palisading granulomas within the papillary and reticular dermis, predominantly composed of a histiocytic cell population with multiple large giant cells (S100-; Fig 3)

Optimizing visiting clerkships in dermatology: a dual perspective approach.

Matching into a dermatology residency program has become increasingly more challenging for medical students. As students continue to explore various methods to help them standout to programs, recent medical literature has continued to show evidence of the important role that visiting clerkships play. Visiting clerkships offer several benefits to both students and programs. In order to optimize visiting clerkships, the perspectives of both students and programs are each examined with recommendations provided to help maximize its benefits

c-Src/Cav1-dependent activation of the EGFR by Dsg2.

The desmosomal cadherin, desmoglein 2 (Dsg2), is deregulated in a variety of human cancers including those of the skin. When ectopically expressed in the epidermis of transgenic mice, Dsg2 activates multiple mitogenic signaling pathways and increases susceptibility to tumorigenesis. However, the molecular mechanism responsible for Dsg2-mediated cellular signaling is poorly understood. Here we show overexpression as well as co-localization of Dsg2 and EGFR in cutaneous SCCs in vivo. Using HaCaT keratinocytes, knockdown of Dsg2 decreases EGFR expression and abrogates the activation of EGFR, c-Src and Stat3, but not Erk1/2 or Akt, in response to EGF ligand stimulation. To determine whether Dsg2 mediates signaling through lipid microdomains, sucrose density fractionation illustrated that Dsg2 is recruited to and displaces Cav1, EGFR and c-Src from light density lipid raft fractions. STED imaging confirmed that the presence of Dsg2 disperses Cav1 from the cell-cell borders. Perturbation of lipid rafts with the cholesterol-chelating agent MβCD also shifts Cav1, c-Src and EGFR out of the rafts and activates signaling pathways. Functionally, overexpression of Dsg2 in human SCC A431 cells enhances EGFR activation and increases cell proliferation and migration through a c-Src and EGFR dependent manner. In summary, our data suggest that Dsg2 stimulates cell growth and migration by positively regulating EGFR level and signaling through a c-Src and Cav1-dependent mechanism using lipid rafts as signal modulatory platforms

Just What is Sprawl, Anyway?

Urban sprawl is a hot-button issue in the U.S. Though the term is widely used to describe the distaste for contemporary American suburban and urban development, a select few group of researchers, academics and practitioners have led the response to the argument against sprawl. This paper seeks to characterize sprawl from the perspective of landscape architecture while focusing on quantitative measurements and definitions of sprawl. At its core it examines the issue of the evolution of urban form through time, and offers options for addressing the debates over the negative or positive ramifications of sprawl

Thermo-Mechanical Treatment Effects on Stress Relaxation and Hydrogen Embrittlement of Cold-Drawn Eutectoid Steels

The effects of the temperature and stretching levels used in the stress-relieving treatment of cold-drawn eutectoid steel wires are evaluated with the aim of improving the stress relaxation behavior and the resistance to hydrogen embrittlement. Five industrial treatments are studied, combining three temperatures (330, 400, and 460 °C) and three stretching levels (38, 50 and 64% of the rupture load). The change of the residual stress produced by the treatments is taken into consideration to account for the results. Surface residual stresses allow us to explain the time to failure in standard hydrogen embrittlement test

β1-integrins signaling and mammary tumor progression in transgenic mouse models: implications for human breast cancer

Consistent with their essential role in cell adhesion to the extracellular matrix, integrins and their associated signaling pathways have been shown to be involved in cell proliferation, migration, invasion and survival, processes required in both tumorigenesis and metastasis. β1-integrins represent the predominantly expressed integrins in mammary epithelial cells and have been proven crucial for mammary gland development and differentiation. Here we provide an overview of the studies that have used transgenic mouse models of mammary tumorigenesis to establish β1-integrin as a critical mediator of breast cancer progression and thereby as a potential therapeutic target for the development of new anticancer strategies