The Effects of Cytoskeletons on the Cultured Human Melanocytes

BACKGROUND: Cytoskeletons, the complex set of protein fibers found in the cytoplasm, have important roles in the movement of cells and subcellular structures and the generation of shapes. Melanocytes have numerous dendritic processes which are in direct contact with many keratinocytes and transfer the melanosomes into the neighboring keratinocytes. Little information is available on the structure and function of cytoskeletons, and the effects of ultraviolet light on the cytoskeletons of the melanocytes. OBJECTIVE: The purpose of this study was to investigate the general cytoskeletal system of cultured melanocytes and to find out the effects of the cytoskeletal antagonists and UVB on the cytoskeletal system of the cultured melanocytes. METHODS: Melanocytes were cultured from adult foreskin and then exposed to various cytoskeletal antagonists and UVB radiation. The changes of the cultured melanocytes were evaluated by using phase contrast microscopy, immunofluorescence staining methods and electron microscopic examinations. RESULTS: Colchicine produced shortening of dendrites, stellate cellular contour and granular fluorescence of the tubulin. Cytochalasin D produced round cellular contour and granular fluorescence of the actin. Acrylamide produced disorganization of cytoplasmic constituents, but no specific fluorescent change was observed. Colchicine also had inhibitory effects on the vimentin. Cellular responses induced by these agents were reversible. UVB caused morphological changes of the melanocytes, but their effects on the organization of the cytoskeletal system could not be detected in this method. CONCLUSION: Microtubules are related to the dendritic movement of the melanocytes. Vimentin may be involved in the transfer of cellular organelles, probably including the melanosomes. Cytoskeletal antagonists produce their characteristic morphological changes to cultured melanocytes.

Erythropoietic Protoporphyria in a Family

Erythropoietic protoporphyria (EPP) is an autosomal dominant condition due to decreased activity of ferrochelatase. The disease is characterized by a wide range of photocutaneous changes and occasionally by liver disease. The level of protoporphyin is raised in erythkocytes and it may also be increased in the feces. We report herein a case of EPP present in a family which was diagnosed by a high free erythrocyte protoporphyrin (FEP) count.

Erythropoietic Protoporphyria in a Family

Erythropoietic protoporphyria (EPP) is an autosomal dominant condition due to decreased activity of ferrochelatase. The disease is characterized by a wide range of photocutaneous changes and occasionally by liver disease. The level of protoporphyin is raised in erythkocytes and it may also be increased in the feces. We report herein a case of EPP present in a family which was diagnosed by a high free erythrocyte protoporphyrin (FEP) count.

Recent Trends of Syphilis Prevalence in Normal Population in Korea-1990

From January to December of 1990, we have evaluated VDRL reactivity among 17,142 apparently normal Korean adults which consisted of 9,151 blood donors in Seoul area, 2,682 pregnant woman delivered at Severance Hospital, Yonsei University and 5,309 physical examinees. The VDRL-positive rates were 0.3% in the blood donors, 0.1% in the pregnant women and 0.8% in the physical examinees but the rates were higher in the age group of 50 years or older. The VDRL titers were below 1:2 in 94% of the VDRL-positive pregnant women and physical examinees. From the comparison of the results obtained by the present author group since 1977, i.e., 2.5 % in 1977, 1.1 % in 1981, 0.6 % in 1986 and 0.4 % in 1990, it is evident that the prevalence of syphilis in Korea is continually decreasing.

Multiple Satellite Pyogenic Granuloma

Multiple satellite pyogenic granuloma developed on the left upper back of a 14-year-old boy after excision of a hemangioma-like lesion. He has had nevus flammeus on the left upper arm since birth with fine linear telangietasiae around the main lesions. Histopathology showed the capillary proliferation in the dermis, and transmission electron microscopy revealed multiple Weibel-Palade bodies, considered an early endothelial cell marker, in the cytoplasm of the endothelial cells. We believe this patient may have the propensity to develop different angiomatous lesions.

Chemical burn due to weed killer, Gramoxone@(paraquat dichloride) / 대한피부과학회지

A 62-year-old farmer was admitted to our department because of second degree chemical burns of both buttocks ten days following accidental contact with Gramoxone, a weed killer. He was treated with oral antibiotics and cold compresses and discharged after the burned area were reepithelialized. Laboratory findings were within normal limits for three weeks. Although lung fibrosis, hepatic and renal failure can be caused by repeated absorption of paraquat (Gramoxone) through injuried skin, systemic absorption through normal skin has not been reported. During the four month follow up period there were no systemic problems nor recurrence of skin lesions. We report herein a case of chemical burns induced by Gramoxone, which is probably an occupational dermatosis of farmers handling weed killers.