Electron microscopic examination of specimens from lesions of eight patients with hyperpigmented and six patients with hypopigmented tinea versicolor and from unaffected skin in each patient was performed. The results are summarized as follows; 1. In hyperpigmented lesions, melanosomes are larger and more singly dispersed than in unaffected skin. 2. In hypopigmented lesions, melanosomes are smaller and less singly diepersed than in unaffected skin. 3. Number of total melanosomes in hyperpigmented and hypopigmented lesions was not different from in unaffected skin.
Humans ; Melanosomes* ; Skin ; Tinea Versicolor* ; Tinea*

Melanosomes were isolated from the human hair by graded centrifugation and identified by transmission and scanning electron microscopic examination. Melanosomes were separated from the keratinous structures by treating with strong NaOH solution for 15 hours. The keratinous structures were removed by centrifugation ai 2,500xg and 3,500xg for 10 minutes respectively at 0 ℃. The isolated melanosomes were collected by centrifugation at 7,800xg at 0 ℃. Scanning electron microscopic examination made it possible to evaluate the global structure of purified melanosomes.
Centrifugation ; Hair* ; Humans* ; Melanosomes* ; Microscopy, Electron, Scanning

No abstract available.
Adult* ; Humans ; Melanosomes* ; Pilot Projects* ; Skin* ; Zebrafish*

We studied 25 cases of clinically diagnosed erythema dyschrornicum perstans (EDP) who were seen in our clinic within 11-year period, from 1975 through 1985, and compared light and electron microscopic findings, and direct immunoflunrescence findings. The results are summarized as follows: 1. There were 16 males(64%) and 9 females(36%). The peak age incidence was in the second decade. 2. The mean age of onset was 18 years(M: 16. 6, F: 19. 4) and the rnean duration was 1.8 years(M: 2.6, F: 1.0). 3. The annual incidence increased from 1981 and was peaked in 1985. 4. The most commonly involvement site was the trunk(92%), the least common involvement(4%) was one of the face, neck, and shoulder combined. 5. The histopathologic findings in most patients shows focal vacuolization of the basal cell layer, pigment incontinence, dermal melanophages. 6. Electron microscopic findings of five patients consist of vauoles with abundant melanosomes in the basal cells, widened intercellular spaces and dermal melanophages.
Age of Onset ; Erythema* ; Extracellular Space ; Humans ; Incidence ; Melanosomes ; Neck ; Shoulder

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

BACKGROUND: There have been only a few morphological studies after laser treatment of pigmented skin lesions. OBJECTIVE: The purpose was to investigate the clinicopathologic and immunohistochemical changes following copper vapor laser treatment of superficial pigmented skin lesions. METHODS: Three patients with Becker's nevus, 1 patient with partial unilateral lentiginosis, and 1 patient with nevus spilus were irradiated with copper vapor laser. Forty-two biopsies were taken before, immediately after, and 3 months after laser treatment. Hematoxylin-eosin, Fontana-Masson, and S-100 protein staining were performed for the evaluation of the histopathologic and immunohistochemical findings of the specimens. RESULTS: Clinically, immediate greyish whitening, immediate erythema, and delayed edema were observed immediately after copper vapor treatment. Histopathologically, suprabasilar separation with elongated cells in the basal cell layer was observed immediately after laser treatment. A few vacuolated cells were found mainly in the basal cell layer. Fontana-Masson and S-100 protein staining positivity decreased a lot in the epidermis, but they hardly decreased in the dermis immediately after laser treatment. CONCLUSION: For the treatment of pigmented skin lesions, copper vapor laser was more effective in the epidermal pigmented structures than the dermal pigmented structures. Selective photothermolysis of melanosome was not so prominent after copper vapor laser treatment.
Biopsy ; Copper* ; Dermis ; Edema ; Epidermis ; Erythema ; Humans ; Lasers, Gas* ; Lentigo ; Melanosomes ; Nevus ; S100 Proteins ; Skin*

BACKGROUND: There have been only a few electron microscopic studies after laser treatment of pigmented skin lesions. OBJECTIVE: The purpose was to investigate the pathologic, immunohistochemical, and electron microscopic changes following Q-switched alexandrite laser treatment of pigmented skin lesions. METHODS: Three patients with acquired bilateral nevus of Ota-like macules, and 2 patients with cafeau lait macule were irradiated with Q-switched alexandrite laser. Forty biopsies were taken before and immediately after laser treatment. Hematoxylin-eosin, Fontana-Masson, and gp100 staining were performed for the evaluation of the histopathologic and immunohistochemical findings of the specimens. Electron microscopic findings were also evaluated. RESULTS: Histopathologically, suprabasilar separations were observed immediately after laser treatment. Vacuolar alterations of pigment-containing cells were frequently found in the epidermis and/or in the dermis. Fontana-Masson and gp100 staining positivity changed to negative or decreased in the epidermis immediately after laser treatment, while they changed to negative in the dermis. Ultrastructurally, epidermal pigment-containing cells frequently showed severe vacuolar changes in the cytoplasm, pyknotic nuclei, and vacuolated and/or fragmented melanosomes immediately after laser treatment. Dermal melanocytes frequently revealed vacuolated and/or fragmented melanosomes immediately after laser treatment. CONCLUSION: Histopathologic, immunohistochemical, and electron microscopic examination of pigmented skin lesions immediately after Q-switched alexandrite laser treatment demonstrated vacuolated or fragmented melanosomes and vacuolar alteration of pigment-containing cells in the epidermis and/or in the dermis, which suggested selective photothermolysis of melanosomes.
Biopsy ; Cytoplasm ; Dermis ; Epidermis ; Humans ; Lasers, Solid-State* ; Melanocytes ; Melanosomes ; Nevus ; Skin*

We report two familial cases of reticulate acropigmentation of kitamura in 20-year-old male and 29-year-old female patients in which reticualte, brownish, slightly depressed pigmentation developed on acral parts of extremities and subsequently extended proximally. Characteristic pits and breaks on palms and soles were noted. Histologic findings revealed epidermal atrophy and enlongation of rete ridges with large amounts of melanin. Electron microscopic findings showed increased melanogenesis in melanocytes and numerous melanosomes and melanosome complex in keratinocytes.
Adult ; Atrophy ; Extremities ; Female ; Humans ; Keratinocytes ; Male ; Melanins ; Melanocytes ; Melanosomes ; Pigmentation ; Young Adult

Pigmentation is induced by production of melanin in specialized organelles termed melanosomes and by transfer of these organelles from melanocytes to surrounding keratinocytes. The chemical basis of melanogenesis is relatively well known but the mechanism of melanosome transfer is not well studied. Various pigmentary disorders and cosmetic applications require the use of depigmenting agents. Currently available topical agents used for the reduction of pigmentation mainly include tyrosinase inhibitors and/or melanocyte-cytotoxic agents. Recently, several agents have been introduced to inhibit melanosome transfer from melanocytes to keratinocytes. However, an experimental model for melanosome transfer is not well established. In this study, a simple assay method using flow cytometry is described.
Cosmetics ; Flow Cytometry ; Keratinocytes ; Melanins ; Melanocytes ; Melanosomes ; Models, Theoretical ; Monophenol Monooxygenase ; Organelles ; Pigmentation

Hypertrichosis is an overgrowth of hair not localized to the anclro en dependent areas of the skin. It may be congenital or acquired, localized or generalized localized hypertrichosis may occur in some types of pigrnentary nevi, chronic inflammation or irration, topical application of androgen or steroid, & localized myxedema. We report herein three i:ases of unilateral localized hypertrichosis with or without a brownish hyperpigmented patch developing on the face of a male adol scent. There are no known cau:,es of localized hyper trichosis. Histopath logically, it is characterized by increased melaniii pigment in the basal layer of the epidermis & enlarged hair follicles containing coarser liair. Electron microscopic findings show normal size & number of melanosomes in both mela nocytes & keratinocytes. Our cases differ frorn BecLers nevus in both clinical & histopatholcgic characteristics.
Epidermis ; Hair ; Hair Follicle ; Humans ; Hypertrichosis* ; Inflammation ; Keratinocytes ; Logic ; Male ; Melanosomes ; Myxedema ; Nevus ; Skin