Akiko Nishijima’s research while affiliated with Tokyo Junshin University and other places

Concentric lamellar bodies are a rarely documented intracytoplasmic structure derived from endoplasmic reticulum and consisting of paired membrane arrays. These bodies stand out clearly from other cytoplasmic structures by virtue of their unique appearance. The membrane arrays are organized according to a pattern of concentric circular profiles surrounding a central cytoplasmic core that is filled with a small number of mitochondria, lipid droplets, and vacuoles. Concentric lamellar bodies have been observed in pathologically altered hepatocytes and also in a variety of cell types in normal animals or animals affected with disease or injured by experimental procedures. The significance of their presence has, however, not yet been determined (Steiner et al., 1964; Le Beux, 1969; Ichihara, 1970; Corvaja et al., 1971; King et al., 1971; Ghadially, 1975). Contemporary literature does not appear to contain any corresponding accounts of the bodies within pilosebaceous apparatuses or other places in skin. During investigations of the fine structure of human hair (Kukita et al., 1971, 1973, 1974; Sato et al., 1973, 1975), some observations pertinent to the concentric lamellar bodies have been made. At the present time it is impossible to relate the presence of the bodies to the ages of the subjects examined or to other phases of the hair growth cycle (except for anagen), but the results will be reported and discussed briefly below.

The presence of 2 forms of the concentric lamellar bodies was observed in the mesenchymal cells within dermal papilla of normal scalp anagen hairs. They are those composed of agranular membrane arrays in association with beta-glycogen particles (glycogen bodies) and those of smooth-surfaced endoplasmic reticulum (smooth-surfaced lamellar bodies). On rare occasions these 2 forms of the concentric lamellar bodies were simultaneously present within the same cells. Transitional forms between the smooth-surfaced lamellar bodies and phagosegresomal granules were also encountered.

Comparative ultrastructural examination and energy-dispersive electron probe X-ray microanalysis were performed on a long standing skin lesion of hemosiderotic histiocytoma. Iron-containing fine particles present in siderosome were the main element of interest. Qualitative study of spectra over the siderosomes clearly demonstrated the characteristic X-ray energy emitted by iron, whereas spectra obtained from adjacent cytoplasm revealed minimal iron peak. On quantitative evaluation of the spectra yielded from various siderosomes, iron counts intensity was found to be proportionally increased with increment in amount and electron opacity of the siderosomal inclusion. Accounts on chemical nature of the siderosomal inclusion and on the presence of lipid residue in cytoplasm were noted.An Hand von Beobachtung bei einer Patientin mit hmosiderinspeicherndem Histiocytom wurden ultrastrukturelle, sowie elektronenmikroskopische energie-dispersive analytische Untersuchungen der Siderosomen durchgefhrt. Die wuchernden Tumorzellen bestanden in feinstruktureller Hinsicht aus Histiocyten und ihre cytoplasmatische Matrix enthielt zahlreiche Siderosomen, die gelegentlich einzeln oder manchmal in groen Gruppen das Cytoplasma durchsetzten. Mit Hilfe des Rntgenanalyseverfahrens wurden punkt-, linien- bzw. flchenmige Auswertungen in Bezug auf Eisenverteilung innerhalb von Tumorzellen angefertigt. Bemerkenswerterweise traten dabei die von Eisen emittierten Rntgenspektren vor allem auf den Siderosomen auf, und mit der Zunahme der siderosomalen Elektronendichte lieen sich ber Siderosomen graduell erhhte Eisenwerte nachweisen, whrend im Cytoplasma immer nur geringfgige Eisenmenge vorhanden waren. Weiterhin wurde der chemische Charakter des im Siderosom abgelagerten Eisens und die mgliche Bedeutung der cytoplasmatischen Lipoidgranula diskutiert.

The fine structure of unmyelinated cutaneous nerve fibers in newborns was examined in lesions of adnexal polyp of neonatal skin. In the neonatal cutaneous nerves, unmyelinated fibers outnumbered myelinated ones. The unmyelinated fibers consisted of Schwann cells, axons and basal lamina. Their ultrastructural organization was basically similar to that in the adult skin. However, some of the unmyelinated fibers contained axonal bundles which suggested a state of cytoarchitectural immaturity or incomplete growth. Phagocytosis of melanosomes by Schwann cells was also observed.

Ultrastructural features of sebaceous glands in newborns were examined in adnexal polyp lesions of neonatal skin. Material for electron microscopy was obtained from the nipple areola of 10 Japanese newborn babies of both sexes, less than 8 days of age. The cell organization of the neonatal sebaceous acini consisted of undifferentiated, differentiating, and mature sebaceous cells, and the sequence of sebaceous transformation seemed to be consistent with that described in the postnatal acini. The sheet of continuous basal lamina covering the sebaceous acini was neither distorted nor convoluted. This configuration in the basal lamina revealed no convincing evidence for physiological involution of the neonatal sebaceous cells were identified at the outer periphery of the sebaceous glnads. Melanocytes in symbiosis with the sebaceous acini in concurrent presence of Langerhans cells.

Electron microscopic observations revealed for the first time a small number of active melanocytes synthesizing distinctive melanin-containing organelles (melanin granules)in the ducts and acini of human sebaceous glands.

Electron microscopic observations revealed for the first time a small number of active melanocytes synthesizing distinctive melanin-containing organelles (melanin granules) in the ducts and acini of human sebaceous glands.

Human anagen scalp hair bulb melanocytes in mitosis were observed by electron microscopy. The metaphase melanocytes were found to maintain their cytologic characteristics, and their perikarya to retain a relatively large number of melanosomes. The relationship between mitosis of a melanocyte and its melanogenic activity is presently being investigated.

The present paper desoribes ultrastructural aspect of lymphatic transport of dermal melanosomes in blue nevus. At least two processes may be responsible for the transport across the lymphatic endothelial wallin vivo; one is the passage of melanophages through the intercellular junctions and the another of free melanosomes. Phagocytosis of melanosomes by lymphatic endothelial cells is discussed.Der Abtransport von dermal liegenden Melanosomen in die lymphatischen Capillaren wird elektronenmikroskopisch untersucht. Unsere Untersuchungsergebnisse an den Hautlsionen bei blauem Naevus lassen erkennen, da mindestens zwei Mechanismen fr den Melanosomentransport durch die lymphatischen Endothelialzellen verantwortlich sein knnen. Ein Proze besteht aus Passage der zahlreiche Melanosomenkomplexe enthaltenden Melanophagen, der andere aus Abtragung der isoliert in die Lederhaut abflieenden Melanosomen. Jedenfalls ist der interendotheliale Raum als Ort der Passage anzusehen, was zumindest fr den Melanophagen sichergestellt ist. Auerdem wird errtert, da die Melanosomen in die lymphatischen Endothelialzellen phagozytiert werden und dort als Melanosomenkomplexe zu finden sind.

The present paper describes ultrastructural aspect of lymphatic transport of dermal melanosomes in blue nevus. At least two processes may be responsible for the transport across the lymphatic endothelial wall in vivo; one is the passage of melanophages through the intercellular junctions and the another of free melanosomes. Phagocytosis of melanosomes by lymphatic endothelial cells is discussed.