A paramagnetic agent causing ochronotic arthropathy.

Magnetic resonance imaging (MRI) identified a paramagnetic substance in the hyaline cartilage of the hips and knees in a patient with ochronosis. Chemical studies characterized the paramagnetic agent as melanin. The free radicals contained in melanin were shown to initiate cytotoxicity. The loss of cartilage in ochronotic arthropathy now can be explained at the electron level using the superoxide theory of oxygen toxicity. Inappropriate metabolism of oxygen also may explain early cartilage degeneration in hemochromatosis, hemosiderosis, and Wilson's disease.

Cornifying Darier disease--a unique variant. I. Report of a case.

A unique variant of Darier disease is described in which a patient was disabled by large, painful, cutaneous horns present on all extremities. The cornified lesions were distinguished by the presence of numerous corps ronds in the basal portion of the greatly hyperkeratotic stratum corneum, hypertrophic dermal villi containing enlarged capillaries, vacuolar dilatation of rough endoplasmic reticulum in sublacunar basal cells, unusually numerous Odland bodies in spinous cells adjacent to lacunae, and persistent attachment of tonofilaments to disrupted desmosomes. Complete separation of tonofilaments from intact desmosomes was not observed. Scanning electron microscopy revealed varied surface morphological appearances of corps ronds and of the epidermal cells covering the elongated dermal villi. The surface cells of cutaneous horns showed little tendency to desquamate.

Atypical melanosomal proteins in human malignant melanoma.

Isolated melanosomes from human malignant melanoma lesions and normal tissues were solubilized with Triton X-100, and proteins were fractionated by polyacrylamide gel electrophoresis. Determination of the relative mobilities of protein bands at different acrylamide gel concentrations allowed the calculation of the molecular size and charge of melanosomal proteins. Three classes of proteins were demonstrable as follows: (a) those found only in melanoma; (b) those found only in normal melanosomes; and (c) proteins common to malignant and control tissues. The similarity of human melanoma protein banding patterns to those previously described in B-16 murine melanoma reaffirms the importance of the latter as a biochemical model for human studies; in addition, the presence of unique proteins in malignant tissue paralleled reports of aberrant polypeptides in organells of several other tumor systems.

Acne fulminans.

Acne fulminans is a unique type of acne that presents acutely and dramatically with fever, weight loss and papulopustular lesions that are highly inflamed, tender and, eventually, ulcerative. These lesions occur on the face, torso and upper extremities. Musculoskeletal symptoms and hematologic manifestations frequently accompany this disorder. Acne fulminans in a 13-year-old boy was effectively treated with isotretinoin, prednisone and minocycline.

Kinetics of in vitro bovine keratohyalin synthesis.

A system is described for the study of the in vitro synthesis of bovine keratohyalin for periods of up to 24 h. Keratohyalin granules appeared morphologically unaltered during culture, although histochemical stains for RNA indicate a markedly diminished RNA content by 6 h. Incorporation of tritiated histidine began slowly, then became linear between 4 and 24 h in serum-containing media. However, following pre-incubation in serum-free media, increased incorporation occurred from time zero. The internal variation of the system using a standard 6 h pulse was +/- 10, +/- 24, +/- 22, +/- 18% in four separate experiments. Measurements of modulations in bovine keratolhyalin synthesis in vitro may prove useful in the development of drugs of therapeutic potential in dermatology.

Conservative excision of penile melanoma.

Penile melanoma is a rare disease, especially in younger men. Most authorities advocate aggressive surgical management by partial or radical phallectomy and in some cases inguinal lymph node dissection. A 27-year old man with a clinical stage I, Clark's level II, microinvasive (less than 0.76 mm) superficial spreading penile melanoma underwent conservative resection and skin grafting without inguinal node dissection. He has normal penile function and is disease free 5 years following surgery. We believe that in clinical stage I, microinvasive penile melanoma, local excision without inguinal node dissection should be the treatment of choice.

Malignant melanoma presenting as nasal obstruction.

Mucosal melanomas arising in the nasal cavity are rare tumors comprising less than 1 percent of all melanomas. Often, the common clinical symptom is nasal obstruction. Grossly, they may or may not be pigmented and frequently attain large sizes. Histologic diagnosis of these tumors may be difficult, requiring immunohistochemical or electron microscopic confirmation. Aggressive surgical management is the treatment of choice in clinical stage I disease. Subsequent surveillance for recurrence is mandatory. Markers such as 5-S-cysteinyldopa may prove useful in staging, prognosticating, and postoperative surveillance for early recurrence, but their exact role has yet to be delineated. Ultimate prognosis is poor.