20 research outputs found
Mouse subcutaneous tissue reaction to calcium hydroxide-based.
Mouse subcutaneous tissue reaction to an embedded calcium hydroxide-based root canal filling material was analyzed histopathologically. After the material was placed within the mouse dorsal subcutaneous tissues, we performed examinations using histopathological, histochemical and immunohistochemical techniques. Two weeks after embedment, the proliferation of granulation tissue had already begun to surround the calcification.Most of the cells observed were macrophages. Likewise, multinucleated giant cells increased significantly. The multinucleated giant cells were observed as two types. In one, the centers of the giant cells were vacuoles, while in the others there were deeply stained calcifications with hematoxylin. Twelve weeks after embedment of the materials, further growth of multinucleated giants cells were sighted. Histochemically, von Kossa-stainpositive granules were observed within the macrophages and multinucleated giant cells as black fine granules. According to the TRAP stained specimens, the multinucleated giant cells especially reacted strongly at 4 weeks. However, the reaction became very weak at 12 weeks. CD68 immunohistochemical staining showed positive reactions in the cytoplasm of the proliferating macrophages and multinucleated giant cells. These results suggest that multinucleated giant cells are present in the surrounding tissues due to implantation of the calcium hydroxidebased root canal filling material, and that the presence of ACP in the cells is due to ingested calcium during active phagocytosis, which would disappear later on
Overview of Cytological Dynamics of Periodontal Ligament Inflammatory Lesions
Cyto-pathological features of the periodontal ligament tissue inflammatory lesions have somehow been carried out but detailed cellular dynamics remain unclear. Therefore, in this review, we overviewed mainly our recent experimental model studies. That is performed using using ordinary ddY mice and BMP bone marrow transplanted mouse model. Regaring the experimental apical inflammatory periodontitis, at four weeks, micro-CT confirmed the presence of a radiolucent image at the apex of the tooth, which was then removed for histological examination. The results showed granulation tissue with fibrosis gradually formed at the periphery of an abscess. Next, if perforation were large, granulation tissue would grow to form periodontal polyp. Results of micro-CT revealed alveolar bone resorption and widening of periodontal ligament. Histopathological examination showed proliferation of fibroblasts with some round cells and blood vessels in the granulation tissue. Double immunofluorescent staining of GFP and Runx2 revealed that both proteins were expressed in spindle-shaped cells. Double immunofluorescent staining of GFP and CD31 revealed that both proteins were expressed in vascular endothelial cells in morphologically distinct vessels. The results suggest that fibroblasts, periodontal ligament fibroblasts and blood vessels in granulation tissue were derived from transplanted-bone marrow cells. Thus, essential growth of granulation tissue in periodontal polyp was caused by the migration of undifferentiated mesenchymal cells derived from bone marrow, which differentiated into fibroblasts and later on differentiated into other cells in response to injury
Effects of long-term treatment with ethanol on the ultrastructure of the golden hamster parathyroid gland
The ultrastructure of the parathyroid gland in golden hamsters after long-term treatment with ethanol was studied. Male hamsters of experimental groups were given ethanol at the concentration of 7% for 3 and 5 months with food and water freely available. In the ethanol-treated hamsters, the Golgi complexes associated with many prosecretory granules were well developed and many secretory granules were located near the plasma membrane as compared with those of the control animals. Exocytotic events were observed in 5-month-treated animals. These findings suggest that the secretory activity of the parathyroid gland is stimulated after long-term treatment with ethanol
Ultrastructure of the parathyroid gland of the young golden hamster after short-term treatment with ethanol
We studied the ultrastructure of the parathyroid gland of young golden hamsters after short-term treatment with ethanol (1.5 gkg bw or 6.0 gkg bw). We did not find any ultrastructural changes of the parathyroid gland after administration of 1.5 g/kg ethanol. In the hamsters, 3 hours after administration of 6.0 g!kg ethanol, the mean serum calcium concentration was significantly low as compared to that of the control animals. In the parathyroid gland 1 hour after administration of 6.0 glkg ethanol, the Golgi complexes associated with a few prosecretory granules and the volume density occupied by the Golgi complexes decreased compared with that of the control animals. In the parathyroid glands 3 hours after administration of 6.0 g/kg ethanol, the Golgi complexes decreased as compared with those of the control animals, while the large vacuolar bodies increased. These findings suggest that the cellular activity of the parathyroid gland is suppressed after short-term treatment with ethanol. Intracellular lumen was found in the parathyroid chief cells 3 hours after administration of 6.0 &kg ethanol, and the significance of this structure is discussed
Effects of progesterone on the ultrastructure of the golden hamster parathyroid gland
The ultrastructure of the parathyroid
glands in golden hamsters after administration of
progesterone was investigated. In the parathyroid glands
of the female hamsters after administration of
progesterone, the mean serum calcium concentration
was significantly higher when compared to that of the
control hamsters. In the male experimental hamsters, the
percentage area occupied by Golgi complexes and lipid
droplets was significantly increased when compared to
that of the control hamsters, respectively. In the female
hamsters after administration of progesterone, the
percentage area occupied by large vacuolar bodies was
significantly decreased when compared to that of the
control hamsters. In the male and female experimental
hamsters, the mean number of secretory granules per
100 pm2 of cytoplasm showed a significant increase
compared with that of the male and female control
hamsters, respectively. These findings suggest that the
secretory activity of the parathyroid glands may be
stimulated in response to hypocalcemia induced by
progesterone
An in vitro study on the effects of melatonin on the ultrastructure of the hamster parathyroid gland
Isolated parathyroid glands from adult
female golden hamsters were incubated on a black
Millipore filter in an incubation vessel containing Ham's
F-12 medium, with or without melatonin at final
concentration of 10-5 M for 1 hour. In the parathyroid
glands used for in vitro treatments with melatonin, the
Golgi complexes associated with a few prosecretory
granules and cisternae of the rough endoplasmic
reticulum showed a significant decrease, and lipid
droplets and lysosomes appeared to be increased
compared with those of the control parathyroid glands.
These changes are considered to be induced by
suppression of the synthesis of parathyroid hormone in
parathyroid glands incubated in a vessel containing
medium with melatonin
Ultrastructure of the parathyroid gland of the young golden hamster after short-term treatment with ethanol
We studied the ultrastructure of the parathyroid
gland of young golden hamsters after short-term
treatment with ethanol (1.5 gkg bw or 6.0 gkg bw). We
did not find any ultrastructural changes of the parathyroid
gland after administration of 1.5 g/kg ethanol. In
the hamsters, 3 hours after administration of 6.0 g!kg
ethanol, the mean serum calcium concentration was
significantly low as compared to that of the control
animals. In the parathyroid gland 1 hour after
administration of 6.0 glkg ethanol, the Golgi complexes
associated with a few prosecretory granules and the
volume density occupied by the Golgi complexes
decreased compared with that of the control animals. In
the parathyroid glands 3 hours after administration of 6.0
g/kg ethanol, the Golgi complexes decreased as
compared with those of the control animals, while the
large vacuolar bodies increased. These findings suggest
that the cellular activity of the parathyroid gland is
suppressed after short-term treatment with ethanol.
Intracellular lumen was found in the parathyroid chief
cells 3 hours after administration of 6.0 &kg ethanol,
and the significance of this structure is discussed
Ultrastructural substrates for increased lung water content in experimental pulmonary edema
We examined the relationship between the
incidence of ultrastructural changes in the alveolar
septum and the extravascular lung water content.
Pulmonary edema was induced in 18 mongrel dogs by
either dextran (n=12) or alloxan (n=6) administration.
Six other dogs served as controls. Extravascular lung
water content was measured by the thermal-dye double
indicator dilution method. Specimens of lung tissue were
examined with an electron microscope, and the
incidence of 13 types of pathological changes in the
alveolar septum was studied. For each type of
pathological change, the incidence was correlated with
the magnitude of lung water content. The following
results were obtained. The incidence of edematous
changes in the alveolar interstitium (widening of the
interstitial space, and dispersion and disarray of collagen
fibres in the interstitial space) was well correlated with
lung water content (r=0.78, p<0.01, and r=0.84, pc0.0 1,
respectively). The correlation was not significant in the
remaining types of changes. We conclude that the
incidence of the pathological changes in the alveolar
septum is increased along with the increase in the
content of lung water in both dextran- and alloxaninduced
experimental pulmonary edema in dogs
Effects of long-term treatment with ethanol on the ultrastructure of the golden hamster parathyroid gland
The ultrastructure of the parathyroid gland in
golden hamsters after long-term treatment with ethanol
was studied. Male hamsters of experimental groups were
given ethanol at the concentration of 7% for 3 and 5
months with food and water freely available. In the
ethanol-treated hamsters, the Golgi complexes
associated with many prosecretory granules were well
developed and many secretory granules were located
near the plasma membrane as compared with those of
the control animals. Exocytotic events were observed in
5-month-treated animals. These findings suggest that the
secretory activity of the parathyroid gland is stimulated
after long-term treatment with ethanol