1/8. Myeloma with xanthoderma due to an IgG lambdamonoclonal anti-flavin antibody.When yellow skin and yellow hair developed in an elderly patient with multiple myeloma, we ruled out the usual causes of such pigmentation but identified a monoclonal IgGlambda (lgGGar) with anti-flavin antibody activity. Purified IgGGar was bright yellow, and the acid-dissociated chromophore was identified as riboflavin by chromatography and absorption spectroscopy. Native IgGGar contained 1.45 moles of flavin per mole of IgG, and increased to 2 moles with addition of riboflavin to saturation. The flavin was localized to the Fab fragment and was bound to IgGGar with high affinity. IgGGar showed strongest affinities for riboflavin, flavin mononucleotide and flavin adenine dinucleotide, and lower affinities for dinitrophenyl derivatives and naphthoquinone. The demonstration of hapten bound to the circulating monoclonal immunoglobulin in this case suggests the possibility of bound but colorless haptens on other myeloma proteins as well as on normal immunoglobulins.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/8. A case of skin hyperpigmentation due to alpha-msh hypersecretion.A case is presented of generalized skin hyperpigmentation due to alpha-msh hypersecretion from the pituitary that was most marked in the light-exposed areas. The patient also had secondary adrenal dysfunction, peripheral lymphadenopathy, streptococcal glomerulonephritis and malabsorption. Analysis of this patient's alpha-msh using high-pressure liquid chromatography (HPLC) showed a novel acetylation profile compared to normal individuals and to patients with Cushing's disease and Nelson's syndrome. Glucocorticoid replacement therapy resulted in suppression of alpha-msh hypersecretion and complete resolution of the illness.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
3/8. skin pigmentation associated with minocycline therapy.A patient on long-term minocycline therapy developed blue-black discoloration on the legs. Skin biopsy specimens from the pigmented areas were examined by light and electron microscopy and energy-dispersive X-ray microanalysis. Pigmented granules were present at all levels of the dermis and subcutaneous fat tissues. Ultrastructural examination showed electron-dense granular material within the cytoplasm of dermal macrophages and energy-dispersive X-ray microanalysis indicated that the granules contained iron. Thyroid tissue obtained by aspiration biopsy showed the presence of fine brown granules within the cytoplasm of the follicular epithelial cells. An extract of skin from the pigmented areas was subjected to high performance liquid chromatography and minocycline was detected.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
4/8. incontinentia pigmenti: eosinophil chemotactic activity of the crusted scales in the vesiculobullous stage.To investigate the mechanisms underlying eosinophil infiltration into the epidermis in incontinentia pigmenti (IP), we studied the eosinophil chemotactic activity in extracts of the crusted scales from three patients with IP in the vesiculobullous stage. Eosinophil chemotactic activity was detected in the eluates from a Sephadex G-75 chromatography column between the vitamin B12 and phenol red markers. The chemotactic activity was heat-stable and resistant to enzyme digestion, and recovered after ether extraction at low pH. leukotriene b4 (LTB4) was demonstrated in the fractions with high eosinophil chemotactic activity. These findings suggest that LTB4 plays an important role in the accumulation of eosinophils within the epidermis in IP, in the vesiculobullous stage. blood eosinophilia, however, may not be induced by the eosinophil chemotactic factors in the scales.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
5/8. Mepacrine pigmentation in systemic lupus erythematosus. New data from an ultrastructural, biochemical and analytical electron microscopic investigation.A case of mepacrine pigmentation occurring in a patient with systemic lupus erythematosus has been investigated by fluorescent light microscopy, gas--liquid chromatography and analytical electron microscopy. There is strong evidence for the presence of mepacrine itself within the typical granules, which have been shown by electron microscopy to be membrane bound and intracellular. Analytical electron microscopy also showed that the granules contain large quantities of iron and smaller quantities of sulphur.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
6/8. Brilliant Lake Red R as a cause of pigmented contact dermatitis.Twenty-three patients suffering from pigmented contact dermatitis caused by cosmetics containing Brilliant Lake Red R were observed. Commercial samples of Brilliant Lake Red R proved to contain many ethyl acetate extractable impurities; 1-phenylazo-2-naphthol and azobenzene were isolated and identified. To determine the responsible allergens, five patients were examined by patch tests with purified samples of azo-dyes and the unidentified fractions of ethyl acetate extractable impurities. Three out of five showed weaker reactions to purified samples of Brilliant Lake Red R and the other two showed equal reactions compared to the commercial product. 1-Phenylazo-2-naphthol was found to be a strong allergen in all cases but none showed a positive reaction to azobenzene. Some unidentified fractions also gave positive results. patch tests were performed with 4-phenylazo-1-naphthol, 4-phenylazo-1-naphthol-2-carboxylic acid, and 2,4-bis(phenylazo)-1-naphthol, as structurally related compounds derived from 1-naphthol. All gave negative and they were not detected in the ethyl acetate extractable impurities by thin-layer chromatography.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
7/8. Sneddon's syndrome, anti-cardiolipin antibody and glomerular thrombosis.Sneddon's syndrome, cerebrovascular thrombosis and livedo reticularis, is often a variant of the "primary" anti-phospholipid syndrome (PAPS). We report a woman with PAPS, presenting as Sneddon's syndrome, with renal impairment and glomerular thrombosis on renal biopsy. An IgG anti-cardiolipin antibody (aCL) was identified. The aCL was purified by affinity chromatography, gel filtration chromatography and ion-exchange chromatography, assayed in a modified ELISA and found to be of the type that requires the plasma protein beta 2-GPI to bind aCL. As beta 2-GPI has anticoagulant properties it is postulated that its interaction with aCL has a pathogenic role in the thrombotic lesions associated with aCL.- - - - - - - - - - ranking = 3keywords = chromatography (Clic here for more details about this article) |
8/8. Phototoxic textile dermatitis ("bikini dermatitis").Phototoxic textile dermatitis with subsequent hyperpigmentation developed in two patients after they wore bikini bathing suits. After extraction of the dye from the bathing suits, 15 fractions could be visualized by two-dimensional thin-layer chromatography. Two of these fractions are found in Disperse Blue 35, an anthraquinone dye known to give rise to occupational phototoxic dermatitis, but which, to our knowledge, has never been reported to cause dermatitis in consumers. One of the two fractions was also found to cause phototoxic reactions in normal subjects.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |