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51.
Toshio Nishimura Keizo Tsuruhara Keiko Naito Junko Hirohara Sotokichi Morii 《Pathology international》1989,39(5):281-288
To examine the effect of colchicine on ethionine induced fatty liver, adult female rats were starved overnight and then injected i.p. with 1 g kg ethionine at 11th hour of fasting; then a half of the rats were also injected i.p. with 2.5 mg kg colchicine twice at 3 and 6 h after the single administration of ethionine. Similarly, fasted control rats were injected i.p. with vehicle alone at the above times. All of the rats were sacrificed after a 20 h fast, and the hepatocytes in periportal areas were observed ultra-structurally. In addition, total lipids in the liver tissue were extracted and determined biochemically. Although similar significant increases of triglyceride were observed in the liver tissue of all ethionine-injected rats, the hapatocytes in the group treated with both chemicals had fewer cytoplasmic fat globules (CFG) than those in the group treated with ethionine only. On the other hand, the diameters of markedly increased membrane-bound lipid particles (MLP) in the double treated group were distributed mainly in the range 0.2–0.4 μm, compared with those (0.1-0.2 μm) in the other groups. These findings indicate that colchicine inhibits the development of CFG in ethionine injured hapatocytes. Acta Pathol Jpn 39: 281∼288, 1989. 相似文献
52.
Keiko Yamamoto‐Shimojima Taichi Imaizumi Hiroyuki Akagawa Hitoshi Kanno Toshiyuki Yamamoto 《American journal of medical genetics. Part A》2020,182(3):521-526
Primrose syndrome is a congenital malformation syndrome characterized by intellectual disability, developmental delay, progressive muscle wasting, and ear lobe calcification. Mutations in the ZBTB20 gene have been established as being accountable for this syndrome. In this study, a novel de novo ZBTB20 mutation, NM_001164342.2:c.1945C>T (p.Leu649Phe), has been identified through whole exome sequencing (WES) in a female patient presenting a typical Primrose phenotype. Because the present patient exhibited recurrent otitis media, detailed immunological examinations were performed in this study and subnormal immunoglobulin levels were firstly identified in a Primrose patient. Anatomical anomaly of the inner ear has never been reported in this patient and WES data did not include any relevant variants causally linked with the immunologic defect. Thus, there is a possibility of a relation between an unclassified immunodeficiency with selective IgG2 deficiency and Primrose syndrome and this may be the reason of recurrent otitis media frequently observed in Primrose patients. Because subnormal levels of IgG2 in this patient might be caused by an unrelated and still uncharacterized genetic cause, further studies are required to prove the causal link between aberrant ZBTB20 function and immunodeficiency. 相似文献
53.
54.
Glomerular expression of cell-cycle-regulatory proteins in human crescentic glomerulonephritis 总被引:4,自引:0,他引:4
Kosaku Nitta Shigeru Horita Kazuho Honda Keiko Uchida Teruo Watanabe Hiroshi Nihei M. Nagata 《Virchows Archiv : an international journal of pathology》1999,435(4):422-427
To elucidate the mechanism underlying crescentic formation, we assessed the phenotypic characterization and cell-cycle protein expression in human crescentic glomerulonephritis (CRGN). Kidney tissue specimens taken from CRGN patients (10 patients with pauci-immune type rapidly progressive glomerulonephritis (RPGN), 2 patients with Henoch-Schönlein purpura nephritis, and 1 patient with IgA nephropathy) were examined immunohistochemically. Most of the cellular components of the crescents expressed cytokeratin, whereas few cells expressed PHM-5. CD68-positive cells were minor components of cellular crescents, indicating that the major principal cellular component of the crescents is made up of cells with the parietal glomerular epithelial cell (PEC) phenotype. Additionally, serial section analysis revealed that Ki-67-positive cells in the crescents were frequently cyclin-A positive and Bcl-2 positive, but seldom cyclin-B1 positive. Moreover, the expression of cyclin-dependent kinase inhibitor p27Kip1 was low in the cellular crescents, despite being exclusively positive in podocytes within the same section. We concluded that the major component of the cellular crescents is made up of PECs and that apparent expression of cyclins and Bcl-2 and restrained expression of p27Kip1 may be synergistically associated with the development of cellular crescents in human CRGN. 相似文献
55.
Toshiyasu Shimizu Keiko Sasaki Michio Kato Hideyuki Arimitsu Sadayuki Ochi Naoko Shigemori Eddy Bagus Wasito Takashi Yokochi Takao Tsuji 《Clinical and Vaccine Immunology : CVI》2005,12(1):157-164
We examined the activation of intraperitoneal T cells in BALB/c mice by the Escherichia coli enterotoxin B subunit, which induced a specific Th2 type of T-cell response to intraperitoneally coadministered bovine immunoglobulin G. The numbers of both γδ and αβ T cells increased significantly after intraperitoneal administration of the B subunit in a time-dependent manner; these numbers were not affected by the B-subunit G33D mutant, which is defective in GM1 ganglioside-binding ability. Early after administration a small number of γδ T cells produced either interleukin-4 (IL-4) or gamma interferon, while late after administration primarily IL-10-producing γδ T cells were detected. γδ T cells induced by the B subunit did not express a characteristic V gene over the time course of the study. The induction of γδ T cells did not occur in athymic nu/nu mice but could be induced upon transplantation of fetal AKR thymus-like αβ T cells. γδ T cells in athymic nu/nu mice with a fetal thymic graft predominantly expressed the donor Thy-1.1 antigen but not the host Thy-1.2 antigen. The induction of these T cells, however, could not be restored by coadministration of the B subunit with peritoneal cells from normal mice. These results suggest that the B subunit activates intraperitoneal γδ and αβ T cells in a manner dependent upon its ability to bind to GM1 ganglioside. γδ T cells induced by the B subunit are Th2-type cells derived from the thymus. These γδ T cells may be functionally involved in specific Th2 responses to the B subunit, which possibly acts as an adjuvant through the influence of αβ T cells. 相似文献
56.
Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC. 相似文献
57.
HNF-4, a member of the nuclear receptor superfamily, binds to HNF-4 response elements (HRE), consisting of a direct repeat of the hexameric half-sites spaced by 1 nt (direct repeat 1) and activates a number of genes, which play central roles in fatty acids and glucose metabolism. Glucose-6-phosphatase (G6Pase) catalyzes the terminal step in the gluconeogenic and glycogenolytic pathways. A previous study has shown that HNF-4 binds to two DR1s in the regions A (located between -266 and -234) and B (located between -306 and -274) on the human G6Pase promoter. We found that the region B contains the one more DR1 element, composed of the two half-sites, designated half-sites a and b, the latter of which overlaps with the previously identified DR1 consisting of two half-sites, designated half-sites b and c. In this study, electrophoretic mobility shift assay (EMSA) using point mutations in each half-site a, b, or c indicated that HNF-4 binds to the combination of half-sites a and b, but not to half-sites b and c. Furthermore, mutational analysis demonstrated that, in the context of the human G6Pase promoter, the half-sites a and b, but not the half-sites b and c, are required for the stimulatory effect of HNF-4. These results suggested that the DR1 element containing the half-sites a and b is a functional HRE that mediates the induction of hG6Pase promoter activity by HNF-4. 相似文献
58.
The course ofAngiostrongylus cantonensis infection in athymic nude and neonatally thymectomized mice
BALB/c athymic nude and thymus-reconstituted nude mice and neonatally thymectomized BALB/c mice were infected with stage 3 larvae ofAngiostrongylus cantonensis and the worm burdens of the mice were determined at various times after infection. When the nude and thymectomized mice were exposed to the parasite, some worms were found to migrate from the brain to lungs but died there without reaching maturity. This pulmonary arterial migration of the worms in the nude mice did not occur following thymic reconstitution. These data suggest that the inability of murine intracranial worms to migrate to the lungs is at least in part due to thymus-dependent mechanisms, and also that the failure of worm maturation in mouse lungs might be due to thymus-independent immune mechanisms and/or nonimmunological mechanisms. 相似文献
59.
We studied the contribution of atrial contraction to ventricular filling by modelling the right heart and the associated vasculature.
Right atrial and ventricular contractions were represented by periodically varying volume elastances which are independent
of loading conditions. The values of these elastances were experimentally determined. The systemic veins, the tricuspid valve
and the pulmonary arteries were all represented by impedance networks. For these impedances we used as much experimentally
obtained information as possible. The dynamic pressure and flow waveforms observed in the model under control conditions generally
agreed with those reported in the literature. We therefore proceeded to analyze the effects of changing the time interval
between atrial systole and ventricular systole, atrial contractility, heart rate, and blood inertance. There was an optimal
atrial systole-ventricular systole interval of about 0.1 sec for ventricular filling. Stroke volume of the ventricle was enhanced
by an increase in atrial contractility, a decrease in heart rate, and an increase in blood inertance. The effect of changing
atrial compliance was found to be dependent on heart rate. Contribution of atrial contraction to ventricular filling was also
found to be more significant during exercise than at rest. 相似文献
60.
Hashimoto K Murakami H Itoh K 《Shinrigaku kenkyu : The Japanese journal of psychology》2002,73(2):186-191
Changes in correlation dimensions of the electroencephalogram (EEG) were examined in three different tasks. These three tasks differed from each other with respect to the number of procedures. In the present experiment, left-hand movement and mental arithmetic were controlled, respectively, during an auditory linguistic task. Subjects were 13 healthy right-handed males. EEG signals from eight electrode sites were analyzed and the correlation dimensions were obtained. In addition, the relative power was obtained for the alpha band. An increase in the number of procedures yielded high dimensionality on the occipital EEG. In contrast, left-hand movement had no significant effect on EEG dimensions over the motor area. The relative power of the alpha band was seen to decrease in all channels as the number of procedures increased. The fact that changes in EEG dimensions did not necessarily exhibit a simple correspondence to changes in alpha wave activity was also discussed. 相似文献