Becker's nevus or Becker's melanosis is a distinct clinical entity in which epimal thickening may be minimal and hairiness and pigmentation obvious. 1Ne report a case of 14-year-old female suffering from Beckers melanosis with multiple and extensive skin lesions. The electron microscope revealed that the melanocytes were bulky with increased melanogenesis and an increased number of melanosomes was found in the keratinocytes. In addition, a large number of melanosomes were seen individually in the keratinocytes.
Adolescent ; Female ; Humans ; Keratinocytes ; Melanocytes ; Melanosis ; Melanosomes ; Nevus* ; Pigmentation ; Skin

No abstract available.
Humans* ; Melanocytes* ; Tretinoin*

No abstract available.
Hair* ; Melanocytes* ; Nevus, Halo*

No abstract available.
Hypopigmentation* ; Melanins* ; Melanocytes* ; Melanosis*

No abstract available.
Eczema ; Inflammation ; Melanocytes ; Nevus

BACKGROUND: The growth of cells is closely related to components in a culture medium. There are many reports about cellular characteristics of melanocytes grown in a PMA-contained medium. However, only a few reports have been studied by using a physiologic mitogens-contained medium. To understand melanocyte in vivo, it is necessary to know the cellular biology of melanocytes grown in a physiologic mitogens-contained medium. OBJECTIVE: To investigate any differences between melanocytes grown in phorbol 12-myristate 13-acetate(PMA)-contained medium and in physiologic mitogens-contained medium. METHOD: We examined morphology, number and melanin contents of cultured human melanocytes grown in a PMA-contained medium and physiologic mitogens-, such as bFGF, ET-1 and a a-MSH contained medium. Result : The results are summarized as follows : 1. There were no significant morphologic differences between cells in PMA-contained medium and in physiologic mitogens-contained medium. 2. The number of melanocytes were significantly more numerous in PMA-contained medium on the 2nd day (p<0.05), but significantly less numerous in the same medium on the 6th day (p<0.05). So, the proliferation rate of melanocytes in PMA-contained medium became lower than in physiologic mitogens-contained medium as time went by. 3. Melanocytes grown in PMA-contained medium had significantly increased melanin contents regardless of the time (p<0.05). Conclusion : The proliferation of melanocytes was better in physiologic mitogens-contained medium, the melanization was higher in melanocytes of PMA-contained medium.
Humans* ; Melanins ; Melanocytes*

Agminated lentigines may be defind as a circumscribed grouping of small pigmented macules arranged in a small or large group, often in a segmental pattern, each macule consisting of a lentiginous epidermal proliferation of melanocytes. We report five cases of agminated lentigines in otherwise healthy persons. Histologic exarnination of the pigmented lesion revealed findings consistent with lentigo simplex.
Humans ; Lentigo* ; Melanocytes

The present study was performed to evaluate the effect of sulfhydryl compounds, cysteine and glutathione, on the size of melanosomes and the ratio of melanosormai stages of epidermal melanocytes in UV-irradiated black mice. The results were as follows; 1. Both of cysteine and glutathione showed significant diminution in the short axis of melanosomes and the percentage of stage 4 melanosomes of epidermal melanocytes in C57BL black mice skin. 2. The length of short axis of melanosomes in glutathione-treated group is smaller than those in cysteine-treated group at the end of 3rd week of intraperitoneal injection. The percentage of stage IV melanosomes significantly decreased in glutathione-treated group and cysteine-treated group at the end of 3rd week and 5th week respectively. 3. In glutathione-treated group, the short axis of melanosomes and the percentage of stage 4 melanosomes both decreased in proportional to the period of intraperitoneal in]ection.
Animals ; Axis, Cervical Vertebra ; Cysteine ; Glutathione ; Injections, Intraperitoneal ; Melanocytes* ; Melanosomes ; Mice* ; Skin ; Sulfhydryl Compounds*

BACKGROUND: Recently, Q-switched lasers have been reported to be successful in treating Ota's nevus without scarring. Utilizing the principle of selective photothermolysis, the Alexandrite laser has been developed for dermal pigmented lesions and tattoos. OBJECTIVE: In this study, we evaluated the clinical, histopathological and ultrastructual effect of the Alexandrite laser in the tretment of Nevus of Ota. METHODS: Forty-seven patients with nevus of Ota were treated with energy densities ranging from 5.0 to 8.0 J/cm2 at a miriimum of 6 week intervals. Sequential skin biopsy specimens were processed for the light microscope with H&E and Fontana-Masson stains and the electron microscope. RESULTS: The average number of treatments were 2.8 per patient. After two treatment sessions, 93 % patients 26 to 75% imprivement was seen. After three treatments 50 to 95% improvement was seen. No patients had permanent textual changes or scarring. On light microscop most of the dendritic melanocytes in the upper dermis were not observed in biopsy specimens taken after clinical improvement. Electron microscopy revealed damaged melanosomes in the upper dermis immediately after irradiation. CONCLUSION: Treatment with the Alexandrite laser for nevus of Ota is considered to be a safe and effective method.
Biopsy ; Cicatrix ; Coloring Agents ; Dermis ; Humans ; Lasers, Solid-State* ; Melanocytes ; Melanosomes ; Microscopy, Electron ; Nevus of Ota* ; Skin

BACKGROUND: Nevus depigmentosus was first reported in 1884 by Lesser. It is defined as a congenital non-progressive hypopigmented macule or patch that is stable in its relative size and distribution throughout the life of the individual. The etiopathogenesis and histopathological characteristics of nevus depigmentosus are not fully established. OBJECT: The purpose of this study is to investigate the clinical and histopathological characteristics and pathogenesis of nevus depigmentosus. METHODS: Clinieal survey was carried out on forty-nine patients with nevus depigmentosus and two skin biopsies were taken from eighteen patients; from the central part of the depigmented lesion and the border of the lesion including the perilesional normal skin. The sections were stained with hematoxylin-eosin, Fontana-Masson and S-100 protein. The ultrastructural evaluation were also done to detect alternation of melanocytes. RESULTS: The results are as follows ; 1. The lesions were mostly (91.8%) present before the age of three, but some lesions appeared in childhood (8.2%). 2. The lesions were most frequently found on the trunk (42.9%), followed by the face and scalp (20.4%). 3. There were 33 patients (67.3%) with the isolated type, 15 patients (30.6%) with the dermatomal type and one patient with the whorled type. 4. Histopathological studies have shown that the stainability of Fontana-Masson in the lesions of nevus depigmentosus was decreased compared with perilesional nomal skin, but there were no changes in the number of melanocytes. 5. There was a great reduction in the number of melanosomes in melanocytes and keratinocytes of nevus depigmentosus. In keratinocytes, there was some aggregations of melanosomes and some of them showed membrane bound architecture. CONCLUSION: The results of this study support the fact that nevus depigmentosus is caused by functional defects of melanocytes and morphological abnonnalities of melanosomes.
Biopsy ; Humans ; Keratinocytes ; Melanocytes ; Melanosomes ; Membranes ; Nevus* ; S100 Proteins ; Scalp ; Skin