bromochloroacetic-acid and Xeroderma-Pigmentosum

Topics: Acrodermatitis; Amino Acid Metabolism, Inborn Errors; Basal Cell Nevus Syndrome; Epidermolysis Bullosa; Hair Diseases; Humans; Ichthyosis; Keratins; Keratosis; Neurofibromatosis 1; Psoriasis; Refsum Disease; Skin; Skin Diseases; Skin Neoplasms; Tuberous Sclerosis; Tyrosine; Warts; Xeroderma Pigmentosum

Malignant fibrous histiocytoma (MFH) of the conjunctiva is an extremely rare tumour, and only three previous cases have been reported. We describe two patients with MFH of the conjunctiva: a 58-year-old white male with epibulbar tumour who had exenteration and is alive after five years' follow-up, and a 3 1/2-year-old African girl with xeroderma pigmentosum and an MFH of her right eye conjunctiva, the first reported case of this association. The characteristics and the methods of diagnosis of MFH are discussed.

Topics: Child, Preschool; Conjunctival Neoplasms; Eye Enucleation; Female; Follow-Up Studies; Histiocytoma, Benign Fibrous; Humans; Immunoenzyme Techniques; Keratins; Lysosomes; Male; Middle Aged; S100 Proteins; Vimentin; Xeroderma Pigmentosum

Primary epidermal keratinocytes obtained from 25 patients with xeroderma pigmentosum (XP) (nine with XP-A, one with XP-C, two with XP-D, five with XP-E, and eight with XP-variant) exhibited less UV-induced unscheduled DNA synthesis (UDS) than did those from 34 normal subjects. Levels of UDS depended greatly on the type of XP; i.e., 3-17% of the control in XP-A, 14% in XP-C, 33-53% in XP-D, 38-77% in XP-E and 58-98% in XP-variant. The extent of UDS in epidermal keratinocytes was almost the same as that in dermal fibroblasts in XP-C, D, and E, but in three out of eight of the XP-variant the level of UDS in epidermal keratinocytes was significantly lower than that in normal subjects. Clinically, three out of nine XP-A patients developed skin neoplasms before 20 years of age. Both patients with XP-D developed skin neoplasms around 40 years of age. In the five XP-E patients, two developed multiple basal cell epithelioma on sun-exposed areas during the forth decade, and one of them also developed squamous cell carcinoma at the age of 50. Four out of the eight patients with the XP-variant developed various skin neoplasms during their 20s and 30s. These results suggest that a defect in UV-induced UDS in epidermal keratinocytes of XP patients is responsible for skin carcinogenesis and the extent to which this defect occurs tends to relate to the age of onset of skin neoplasms.

Topics: Adult; Age Factors; Child; DNA; DNA Repair; Epidermis; Female; Humans; Keratins; Male; Middle Aged; Skin Neoplasms; Ultraviolet Rays; Xeroderma Pigmentosum

DNA repair synthesis in 8 explant-outgrowth cultures of epidermal cells isolated from variant and complementation groups A and E of xeroderma pigmentosum (XP) was examined by measuring unscheduled DNA synthesis (UDS) on autoradiographs. The extents of UDS in XP epidermal cells were compared with those in normal epidermal cells obtained from 26 subjects. In both normal and XP epidermal cells, UDS was induced dose-dependently by radiation at doses of 5-20 J/m2. XP epidermal cells showed various extents of defect in DNA repair depending on the type of XP. In XP-A, the extent of UDS in epidermal cells was very low, being seen in only 3-10% of the normal epidermal cells. But epidermal cells isolated from XP-E and XP-variants exhibited relatively high levels of residual DNA repair; i.e., 69-84% of the control in XP-E and 67-85% in XP-variant. The extents of UDS in XP epidermal cells were almost the same as those in fibroblastic cells isolated from the same specimens.

Topics: Autoradiography; Cells, Cultured; DNA; DNA Repair; Dose-Response Relationship, Radiation; Epidermal Cells; Epidermis; Fibroblasts; Humans; Keratins; Ultraviolet Rays; Xeroderma Pigmentosum

Topics: Biopsy; Endoplasmic Reticulum; Histocytochemistry; Humans; Keratins; Microscopy, Electron; Skin; Staining and Labeling; Xeroderma Pigmentosum

Topics: Child; Child, Preschool; Female; Humans; Infant; Keratins; Langerhans Cells; Male; Melanocytes; Microscopy, Electron; Pigmentation; Skin; Xeroderma Pigmentosum

Topics: Adolescent; Adult; Child; Child, Preschool; Female; Humans; Keratins; Macrophages; Male; Melanocytes; Microscopy, Electron; Skin Neoplasms; Xeroderma Pigmentosum