Retinoid signaling by all-trans retinoic acid and all-trans retinoyl-beta-D-glucuronide is attenuated by simultaneous exposure of human keratinocytes to retinol.

Retinol and retinyl esters are converted with time to slowly increasing amounts of all-trans retinoic acid (RA) in cultured human keratinocytes. Exogenous RA has been shown to limit retinol oxidation and to increase retinol esterification. Because significant amounts of retinol are present in biologic systems, we examined whether RA and all-trans-retinoyl-beta-D-glucuronide (RAG) interact with retinol in exhibiting their activities on HaCaT keratinocytes maintained in a retinoid-free culture system.

Hereditary progressive mucinous histiocytosis.

We describe hereditary progressive mucinous histiocytosis, a rare autosomal dominant non-Langerhans cell histiocytosis, in a mother and daughter. Both had similar, progressive eruptions of skin-colored to red-brown papules on the nose, hands, forearms, and thighs. Light microscopy showed small collections of epithelioid histiocytes and telangiectatic vessels in the upper dermis of early lesions.

Cutaneous metastatic angiosarcoma with a lethal outcome, following radiotherapy for a cervical carcinoma.

A cutaneous metastatic angiosarcoma was diagnosed in a 79-year-old woman 19 years after radiotherapy for a carcinoma of the uterine cervix. The diagnosis was confirmed by immunohistochemical staining (factor VIII-related antigen and BMA 120) and electron microscopic examination. Surgical treatment of the large tumour, which was situated in the gluteal region, was not feasible, but electron beam therapy resulted in complete remission.

[Idiopathic clubbing of the fingers. Pathogenetic mechanisms and differential etiologic diagnosis].

We report on a patient with marked clubbing of the fingers and toes with watch-glass deformity of the nails, diagnosed as idiopathic clubbing. New findings on the pathogenesis of clubbing provide evidence for the important role of cytokines, especially platelet-derived growth factor and tumor necrosis factor-alpha. The differential diagnosis includes, besides rare primary forms, clubbing in malignant neoplasias and chronic inflammatory diseases of the heart, the lung, the upper gastrointestinal tract and the liver.