1988 Fiscal Year Final Research Report Summary
Studies on the pathogenesis and treatment of congenital and acquired circumscribed cutaneous hypomelanosis
| Project/Area Number |
62570459
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Dermatology
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| Research Institution | Osaka City University Medical School |
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Principal Investigator |
HAMADA Toshio Osaka City University Medical School, Professor, 医学部, 教授 (80046870)
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| Project Period (FY) |
1987 – 1988
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| Keywords | leukoderma centrifugum acquisitum / Sutton's leukoderma / halo congenital nevus / nevus depigmentosus / piebaldism / nevus depigmentosus / まだら症 / piebaldism / 皮膚色素脱失症 |
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| Research Abstract |
Ultrastructural studies of halo congenital nevus were performed. Histopathological features of the pigmented plaque were compound nevus. No significant inflammatory response was present in the dermis. Electron microscopic findings showed melanocytes in halo epidermis decreased in number. In the remaining melanocytes, normal melanosomes decreased and a number of spherical and granular abnormal melanosomes were observed. Langerhans cells in the basal layer of halo epidermis increased and were frequently in contact with lymphocytes. Some nevus cells in the basal layer of epidermis showed pyknotic nuclei and vacuolated cytoplasm. In the dermis, no degenerated nevus cells were observed. Langerhans cells on the epidermis overlying the nevus considerably increased in number and were seen in contact with several nevus cells. They contained nemerous Langerhans granules, lysosomes phagocytosed melanosomes and many vacuoles due to the enlargement of endoplasmic reticulum. Although inflammatory reaction was scarcely observed in halo congenital nevus, these ultrastructural findings suggested a relationship to some type of immunological mechanism for the degeneration of epidermal nevus cells.
In the hypomelanotic skin of piebaldism, electron microscopy revealed that considerable number of melanocytes were stage II to III and formed melanosome conplex in the dendrites. However, there were no melanosomes in the surrounding keratinocytes. The melanocyte-keratinocyte transfer of melanosomes seemed to be impaired. In the another area of hypomelanotic skin, there were no melanocytes and increased indeterminate calls. In the islands of pigmentation within hypomelanotic skin, spherical or irregular in shape and partially melanized melanosomes, and also ellipsoidal lamellar normally melanized melanosomes were observed.
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Research Products
(12 results)
