Search results

Search:
in the keywords: pigmentation

Sort By:

Limit search:

Hyperpigmentation of the oral mucosa induced by an antiretroviral drug – a case report

100%

Cavalcanti L. G., de Souza R. B., de Almeida C., de Lima A. A. S.

Polski Przegląd Otorynolaryngologiczny

2015

vol. 4(3)

38-42

Pigmented lesions of the oral cavity are relatively common. They represent a group of clinical entities ranging from physiological changes to manifestations of local or systemic disease. Hyperpigmentation is the result of accumulation of pigment within the tissue. In general, pigmentation of oral tissues may occur due to accumulation of melanin or silver salts. The objective of this paper is to report a case of pigmented oral lesions in a HIV-positive patient treated with zidovudine. The patient is a HIV positive, smoked and took antiretroviral drugs irregularly. Physical examination revealed multiple brown macules in the oral cavity. Biopsy was performed and histopathological examination confirmed the diagnosis of oral melanin hyperpigmentation. This case demonstrates the importance of proper diagnosis and planning for oral pigmented lesions

Splenic eumelanin differs from hair eumelanin in C57BL/6 mice.

75%

Plonka P. M., Michalczyk D., Popik M., Handjiski B., Slominski A., Paus R.

Acta Biochimica Polonica

2005

vol. 52

issue 2

433-441

The presence of melanin in spleens of black C57BL/6 mice has been known for long. Although its origin and biological functions are still obscure, the relation of splenic melanin to the hair follicle and skin pigmentation was suggested. Here, we demonstrated using for the first time electron paramagnetic resonance spectroscopy that black-spotted C57BL/6 spleens contain eumelanin. Its presence here is a "yes or no" phenomenon, as even in the groups which revealed the highest percentage of spots single organs completely devoid of the pigment were found. Percentage of the spotted spleens decreased, however, with the progress of telogen after spontaneously-induced hair growth. The paramagnetic properties of the spleen eumelanin differed from the hair shaft or anagen VI skin melanin. The splenic melanin revealed narrower signal, and its microwave power saturability betrayed more heterogenous population of paramagnetic centres than in the skin or hair shaft pigment. Interestingly, the pigment of dry hair shafts and of the wet tissue of depilated anagen VI skin revealed almost identical properties. The properties of splenic melanin better resembled the synthetic dopa melanin (water suspension, and to a lesser degree - powder sample) than the skin/hair melanin. All these findings may indicate a limited degradation of splenic melanin as compared to the skin/hair pigment. The splenic eumelanin may at least in part originate from the skin melanin phagocyted in catagen by the Langerhans cells or macrophages and transported to the organ.

Refine search results

1 Acta Biochimica Polonica

1 Polski Przegląd Otorynolaryngologiczny

1 2015

1 2005

1 Cavalcanti L. G.

1 Handjiski B.

1 Michalczyk D.

1 Paus R.

1 Plonka P. M.

1 Popik M.

1 Slominski A.

1 de Almeida C.

1 de Lima A. A. S.

1 de Souza R. B.

Search results

Hyperpigmentation of the oral mucosa induced by an antiretroviral drug – a case report

Splenic eumelanin differs from hair eumelanin in C57BL/6 mice.