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Volume 41 (1978)
- Issue 5 Pages 389-
- Issue 4 Pages 293-
- Issue 3 Pages 195-
- Issue 2 Pages 103-
- Issue 1 Pages 1-
Volume 41, Issue 4
Displaying 1-8 of 8 articles from this issue
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Tohru IZUMI, Akira HATTORI, Norio HIGUMA, Kohji TAMURA1978 Volume 41 Issue 4 Pages 293-308
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSMorphological alterations in idiopathic cardiomyopathy were examined and their clinicopathological significance was discussed. Six cases of congestive type and five of hypertrophic type chosen from 22 patients according to our strict criteria were examined by light and electron microscopy.
The diameter values of cardiac muscle fibers were broadly distributed with multiple peaks in congestive cases and with 4 peaks in the hypertrophic cases in contrast to the 2 peaks in the controls. The chief electron microscopic alterations consisted of myofibril disorientation and Z band abnormalities. The congestive cases were characterized by decreased and disarrayed myofibrils (loose myofibril disorientation), whereas the hypertrophic cases by abundant myofibrils characteristically entangled with each other (tight myofibril disorientation).
The Z band showed 3 types of abnormalities. Type 1 was characterized by widening, bifurcation and overriding of Z bands while the regular sarcomere was retained. The changes were more conspicuous in the hypertrophic cases than in the congestive cases. Type 2 was represented by clumping of Z band substance, and Type 3 by an interwoven form of electron dense fibers. Types 2 and 3 were seen in some of the hypertrophic and congestive cases.
The tight myofibril disorientation and Type 1 of Z band abnormalities were considered important cytopathological clues for the diagnosis of the hypertrophic type of idiopathic cardiomyopathy.View full abstractDownload PDF (24294K) -
Marie YAMADA, Hidehiro OZAWA1978 Volume 41 Issue 4 Pages 309-323
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSTooth germs of killifish were examined by both ultrastructural and cytochemical methods. The ultrastructure of the dentin in the early calcification stage of its development resembled that of mammals. Numerous extracellular membrane-bounded vesicles, matrix vesicles, were seen in the predentinal space, especially abundantly in the basal portion of the tooth germ. They were more numerous and more uniform in appearance than in any other higher vertebrates.
Where calcification was going to start, slightly identifiable needles of apatite crystals were found in the vesicular structures. Crystals increase in number filling up the vesicles and then their surroundings, finally to form many calcified spherules. Where calcification was more extensive, the matrix vesicles were no longer visible having been buried calcified among spherules. Contrary, to popular belief, there was no relationship seen between collagen fibrils and the initial deposits of minerals, that is, collagen fibrils did not seem to work as the initial site of calcification. Instead, matrix vesicles and plasma membranes of odontoblasts likely were involved in calcification as they both showed alkaline phosphatase activity.
The ultrastructural and cytochemical findings from this study thus indicated that calcification of the killifish tooth germs was initiated not in the enamel, but in their dentin by the matrix vesicles which were liberated into the dentin matrix from odontoblasts mainly by way of fragmentation of cell processes.View full abstractDownload PDF (35053K) -
Hisao OKAMOTO, Kazunori ISHIMURA1978 Volume 41 Issue 4 Pages 325-337
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSDevelopment of intercellular junctions in duodenal epithelium in the chick embryo was studied by electron microscopy using the thin-section and freeze-fracture techniques.
Incomplete tight junctions are already seen in 6 and 7 day old embryos at the apical portion of the lateral plasma membrane, and consist of 1-7 strands, their mean death measuring 0.2μm. This corresponds to a “very leaky type”(CLAUDE and GOODENOUGH) of tight junction. Ridges on the PF are discontinuous and rarely cross or link. The tight junctions extend basally at the place where more than three epithelial cells are in contact. On the lateral plasma membrane, particle-aggregates suggesting primitive gap junctions are already recognized. Some are dense aggregations of 3-5 membrane-particles with a halo free of the particles and others are rather loose aggregations of 5-10 particles with an indistinct halo.
In 9 day old embryos, the ridges of the tight junction become more discontinuous, although the frequency of the linkage of the neighboring ridges increases. The compartments bounded by the tight junctional strands are angular. These strands become continuous and the facets surrounded by them are roundish in 12 day old embryos.
The presumptive immature gap junctions show a characteristic polygonal pattern in 9 day old embryos and gradually increase in size.
Mature tight junctions and typical gap junctions of 0.3-0.4μm diameter are seen after 18 days of incubation. The strands number 6-8 and the depth of the tight junction measures about 0.4μm in 18 day old embryos.
In the chick embryo duodenal epithelium, the tight and gap junctions develop independently from each other without any direct interaction between them.View full abstractDownload PDF (25498K) -
Yoshiyuki TAKAHASHI, Heikichi TSUBOUCHI, Kan KOBAYASHI1978 Volume 41 Issue 4 Pages 339-349
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSIn the normal carp livers, Ito cells (fat-storing cells) could be identified with light and electron microscope within the hepatic sinusoidal wall and actually in the Disse's space, but they were almost lacking lipid droplets in the cytoplasm (empty Ito cells) in contrast to the majority of vertebrate species.
After administration of large doses of vitamin A, fat droplets appeared in hypertrophic cytoplasm of enlarged Ito cells, and their size and number increased roughly in proportion to the amounts of vitamin A administered. This evidence was thought to demonstrate that the administration of large doses of vitamin A could convert empty Ito cells into lipid containing ones and further suggested that excess vitamin A administered might be stored in newly prepared lipid droplets of the Ito cells of the liver. In experimentally hypervitaminotic carp, hypertrophic Ito cells showed proliferation of fine filaments in addition to the accumulation of lipid droplets. The correlation between perisinusoidal fibrogenesis in the hepatic lobule and the proliferation of cytoplasmic filaments in the Ito cells was discussed.View full abstractDownload PDF (14968K) -
Kazuo TAIRA, Susumu SHIBASAKI1978 Volume 41 Issue 4 Pages 351-366
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSThe non-ciliated epithelial cells in the air way of mice were examined by electron microscopy. They are flask-like or pyramidal cells dispersed singly or occasionally in pairs. The apical portion of the cells reaches the air way lumen with microvillous projections. Their cytoplasm always contains abundant and variable numbers of small granules (60-170nm in diameter). Close appositions between non-ciliated cells and nerve fibers are frequently observed at their lateral or basal surfaces. Fine structures of the non-ciliated cells are similar to those previously reported in the cells under different designations such as brush cells, basal-granulated cells, cells of neuroepithelial bodies and endocrine cells. The present study proposes that these names express different features of the same cell group collectively called “non-ciliated cells” in this paper. Furthermore images indicating exocytotic granule release are obtained in this study, indicating an endocrine function of these cells.View full abstractDownload PDF (37227K) -
Yutaka TANUMA, Masako OHATA1978 Volume 41 Issue 4 Pages 367-376
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSCells with long single cilia arising from basal bodies in the apical cytoplasm were occasionally revealed in the bile ductular epithelia of bats (Miniopterus schreibersi (Kuhl), Myotis macroductylus (Temminck) and Rhinolophus cornutus (Temminck)). The basal body (distal centriole) was associated with a proximal centriole, so the basal structure was of “two centriole type.” In cross sections of the long tapering cilia the arrangement of ciliary microtubules was determined. In the most proximal portion of the cilia doublet microtubules were arranged in the 9+0 pattern, while in more distal portions alteration and diminution of the doublet fibers occurred, splitting entirely into single microtubuli which were most frequently rearranged in the 6+1 or 7+1 pattern. The occurrence of the 9+0 fiber pattern and the basal structure of “two centriole type” suggested that the biliary ductular cilia might be sensory or chemoreceptive in nature and not motile. Similar cilia are expected to be found distributed widely in the epithelia of the excretory ductal system of large exocrine glands of vertebrate species.View full abstractDownload PDF (10018K) -
Yutaka TANUMA, Masako OHATA1978 Volume 41 Issue 4 Pages 377-384
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSOccurrence of centrioles in non-dividing hepatocytes was examined by electron microscopy in the bat, Miniopterus schreibersi (Kuhl) and Myotis macrodactylus (Temminck), and the chicken. In both species centrioles were mostly found in the apical cytoplasmic area of the hepatocyte near the bile canaliculus. They were invested in a hyaloplasmic halo which was distinct in the chicken but rather indistinct in the bat. There was no difficulty in locating centrioles in the hepatocytes of either species. In the chicken centrioles were found in the attenuated apical cytoplasmic areas of 4-6 hepatocytes surrounding the bile canaliculus, giving us the impression that the occurrence of centrioles in non-dividing hepatocytes might be more frequent in the chicken than in the bat. The centrioles found in non-dividing bat and chicken hepatocytes apparently formed diplosomes. Neither multiple centrioles (comprising more than three) nor centriolar replications were found. Single cilium formation from the centrioles was not observed in either species.View full abstractDownload PDF (10913K) -
1978 Volume 41 Issue 4 Pages 385-387
Published: 1978
Released on J-STAGE: February 20, 2009
JOURNAL FREE ACCESSDownload PDF (308K)
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