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101.
Kenji Kashima Shigeo Yokoyama Tsutomu Daa Iwao Nakayama Torn Iwaki 《Virchows Archiv : an international journal of pathology》1997,430(4):333-338
The influence of free radicals on apoptosis was studied in the human heart; 45 autopsy cases were examined by the nick end labelling method (NELM) that detects DNA fragmentation. Immunostaining for copper-zinc superoxide dismutase (CuZn-SOD) and tissue transglutaminase (tTG) induced frequently during apoptosis were also studied. Positive immunoreaction for tTG was detected in mucinous degeneration of myocardial cells; these same cells were also positive for CuZn-SOD but negative for NELM. Myocardial cells showing basophilic alterations after haematoxylin and eosin staining were also positive for CuZn-SOD but negative for the other markers examined. Positive nuclear reaction by NELM was only observed in myocardial cells showing contraction band necrosis or irregularly shaped nuclei surrounding recent or long-standing infarcted foci. In these the other two markers were negative. Since mucinous degeneration lacks the distinguishing morphological features of apoptosis, immunoreactive tTG in this lesion may not imply that the cells are undergoing apoptosis. tTG can be induced in non-apoptotic conditions and may not be involved in apoptosis induced by infarction. Histological disassociation between CuZn-SOD expression and apoptosis suggests the possibility of a cytoprotective role played by endogenous CuZn-SOD against free radical generation in the human heart. 相似文献
102.
I Nakayama S Noguchi Y Mochizuki N Murakami H Yamashita A Moriuchi S Yokoyama A Noguchi 《Acta pathologica japonica》1984,34(1):19-28
Five cases of adenomatous goiter have been studied by an electron microscope using an immuno-reaction for thyroglobulin (TG) and focusing on the mechanism of endocytosis. Positive stain for TG was demonstrated in follicular lumina, large reabsorbed colloid droplets and small subapical vesicles. Endocytotic vesicles ranging from 320 nm to 1600 nm in diameter were observed in the cytoplasm as pits in the apical plasma membrane. Some of them showed direct connection with the positive stain for TG in the follicular lumen and the others were completely ingested in the cytoplasm. With statistic analysis, a majority of the vesicles showing the positive stain for TG in the cytoplasm distributed in the range of 200 nm to 1200 nm in diameter with the peak in 300 nm to 399 nm and was situated within an extent of the diameter measured from the endocytotic vesicles. Engulfment of colloid by pseudopods and fusion of the reabsorbed colloid droplets were encountered as extremely rare findings and appeared to play no major role for formation of large colloid droplets in adenomatous goiter. 相似文献
103.
104.
Seiiohi Sumino Kazuo Nacsashima Tetsuro Shimamine Toshiaki Abe Hideo Tsuneyoshi Satoru Murao 《Pathology international》1983,33(3):629-643
Autopsy findings in a 40-year-old male with heredofamilial amyloidosis and polyneuropathy are reported. He had been suffering from progressive autonomic as well as sensorimotor dysfunctions. Prominent amyloid deposit was found in the kidney, heart, thyroid, and testis, and less in the interstitium and small vessels of almost all organs. The peripheral nerves, some showing prominent hypertrophy, were most severely involved by amyloid deposit in a form of stellate mass, which ultrastructurally consisted of radially arranged amyloid filaments. In the hypertrophied nerves and ganglia, in addition to amyloid, massive accumulation of acid mucopolysaccharide (AMPS) was seen filling up the interstitial space, which was the cause of hypertrophy. Ultrastructurally, AMPS was seen as finely granular substance. An extracted amyloid from the kidney showed 8 nm filament on negative staining and was estimated of having a molecular weight of 14,000. 相似文献
105.
Yokoyama Y; Takahashi Y; Morishita S; Hashimoto M; Niwa K; Tamaya T 《Molecular human reproduction》1998,4(2):173-177
In a total of 41 endometrial tissue samples, the relationship between
telomerase activity and proliferating cell nuclear antigen (PCNA) labelling
index was studied. In samples of endometrium from the proliferative phase
of the menstrual cycle, telomerase activity was found in 15 out of 17 cases
(88%). Two samples from the early proliferative phase showed negative
telomerase activity and a low PCNA labelling index. However, three out of
16 samples of early secretory phase endometrium showed telomerase activity
and a PCNA labelling index. In mid- to late secretory phase endometrium, in
menopausal endometrium and in decidualized endometrium induced by
progesterone neither telomerase activity nor PCNA labelling was found.
These results suggest that telomerase activity of the endometrium may be
correlated with the proliferative potential of the epithelial cells and
that its activity may be regulated by oestrogen.
相似文献
106.
107.
108.
Yasuaki Yokoyama Masahiko Okada Hiroshi Sumitomo 《Macromolecular chemistry and physics.》1978,179(5):1393-1396
109.
Sato E Miyazawa T Nishimura Y Ikeda Y Kawakami K Mochizuki M Yokoyama N Maeda K Fujita K Kohmoto M Takahashi E Mikami T 《Archives of virology》2001,146(2):379-387
Summary. We have previously reported the construction of a recombinant feline herpesvirus type 1 (FHV-1), designated C7301ddlTK-gag, expressing the Gag precursor protein of feline immunodeficiency virus (FIV). In this study, we report the construction
of a further recombinant FHV-1 (ddlTK(gBp)-gag) which carries an FHV-1 gB promoter sequence upstream of the FIV gag gene of C7301ddlTK-gag. Strong expression of the FIV Gag protein by ddlTK(gBp)-gag was confirmed by immunoblot analyses and enzyme-linked immunosorbent assays. Although C7301ddlTK-gag and ddlTK(gBp)-gag failed to induce anti-FIV Gag antibodies in cats, we confirmed the infectivity and stability of these recombinants
in cats.
Received January 14, 2000 Accepted August 4, 2000 相似文献
110.
Poly(N-isopropylacrylamide)-grafted gelatin (PNIPAM-gelatin) serves as a temperature-induced scaffold at physiological temperature. This study was aimed at determining the effect of the graft architecture of thermoresponsive PNIPAM-gelatin on the surface topography and elastic modulus of the hydrogels prepared with different architectured PNIPAM-gelatins: the surface topography and elastic modulus were determined by atomic force microscopy (AFM). PNIPAM-gelatin surfaces showed an irregularly concavo-convex structure with a vertical interval of approximately 1 microm regardless of the weight ratio of PNIPAM to gelatin (P/G: 5.8, 12, and 18). The elastic moduli of hydrogels varied at measured sites. The mean elastic moduli of PNIPAM-gelatin with the lowest P/G were low, but increased with increasing P/G. Human umbilical vein endothelial cells adhered and spread on PNIPAM-gelatin hydrogels with the highest P/G, whereas reduced adhesion and nonspreading, round-shaped cells resided on the hydrogels with lower P/Gs. Interrelationship between elastic modulus and cell adhesion and spreading potentials were discussed from physicochemical and cellular biomechanical viewpoints. 相似文献