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91.
Nishio J Iwasaki H Sakashita N Haraoka S Isayama T Naito M Miyayama H Yamashita Y Kikuchi M 《Human pathology》2003,34(3):246-252
Undifferentiated (embryonal) sarcoma of the liver (UESL) is a rare pediatric liver malignancy that is extremely uncommon in middle-aged individuals. We studied 2 cases of UESL in middle-aged adults (1 case in a 49-year-old woman and the other in a 62-year-old man) by histology, immunohistochemistry, and electron microscopy to clarify the cellular characteristics of this peculiar tumor. One tumor showed a mixture of spindle cells, polygonal cells, and multinucleated giant cells within a myxoid matrix and also revealed focal areas of a storiform pattern in a metastatic lesion. The other tumor was composed mainly of anaplastic large cells admixed with few fibrous or spindle-shaped components and many multinucleated giant cells. In both cases, some tumor cells contained eosinophilic hyaline globules that were diastase resistant and periodic acid-Schiff positive. Immunohistochemically, the tumor cells showed positive staining for smooth muscle markers, such as desmin, alpha-smooth muscle actin, and muscle-specific actin, and also for histiocytic markers, such as alpha-1-antitrypsin, alpha-1-antichymotrypsin, and CD68. Electron microscope examination revealed thin myofilaments with focal densities and intermediate filaments in the cytoplasm of tumor cells. Our studies suggest that UESL exhibits at least a partial smooth muscle phenotype in middle-aged adults, and this specific differentiation may be more common in this age group than in children. Tumor cells of UESL with smooth muscle differentiation in middle-aged adults show phenotypic diversity comparable to those of malignant fibrous histiocytoma with myofibroblastic differentiation. 相似文献
92.
Bradykinin Stimulates Type II Alveolar Cells to Release Neutrophil and Monocyte Chemotactic Activity and Inflammatory Cytokines 总被引:2,自引:0,他引:2
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Sekiya Koyama Etsuro Sato Hiroshi Nomura Keishi Kubo Masakazu Miura Tetsuji Yamashita Sonoko Nagai Takateru Izumi 《The American journal of pathology》1998,153(6):1885-1893
In the present study, we evaluated the potential of bradykinin (BK) to induce the release of neutrophil and monocyte chemotactic activity (NCA and MCA) and cytokines from an alveolar type II epithelial cell line, A549 cells. BK stimulated A549 cells to release NCA and MCA in a dose- and time-dependent manner (P < 0.001). Checkerboard analysis revealed that both NCA and MCA involved chemotactic and chemokinetic activity. Molecular sieve column chromatography showed three molecular weight masses (near 19 kd, 8 kd, and 400 d) for NCA and several molecular weight peaks (near 66 kd, 25 kd, 19 kd, 16 kd, and 400 d) for MCA. The release of NCA and MCA was inhibited by cycloheximide and lipoxygenase inhibitors (P < 0.01). The NCA and MCA were inhibited by leukotriene B4 (LTB4) receptor antagonist (P < 0.01), and the concentration of LTB4 was high enough for NCA and MCA. Antibodies to interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) attenuated NCA (P < 0.01), and antibodies to monocyte chemotactic protein-1 (MCP-1), G-CSF, and transforming growth factor (TGF)-β attenuated MCA (P < 0.01). The levels of IL-8, G-CSF, MCP-1, and TGF-β increased time dependently (P < 0.01). BK also stimulated the release of ILeukin-6 from A549 cells (P < 0.001). The receptors responsible for the release of NCA, MCA, and individual chemokines involved both BKB1 and BKB2 receptors. These data suggest that BK may stimulate alveolar type II pneumocytes to release inflammatory cytokines, which then may modulate the lung inflammation. 相似文献
93.
A case of polypoid carcinosarcoma of the esophagus is presented. Histologically the bulk of the tumor consisted of a sarcomatous tissue having large foci of osseous and cartilagenous differentiation and infiltrating deeply the wall, whereas a superficially, invasive squamous cell carcinoma associated with in-situ carcinoma was located at the base and luminal surface of the polypoid tumor. Intermingling of the carcinomatous and sarcomatous elements was found only in areas where they appeared to be collided. Ultrastructurally the sarcomatous portion contained cells with fibroblastic features but with no typical epithelial characteristics. Immunoperoxidase staining of the paraffin-embedded histologic sections for keratin proteins revealed, however, some positive spindle cells indicative of epithelial nature in the sarcomatous area, but the great majority of the sarcoma cells were devoid of keratin. These combined findings strongly suggest that the sarcomatous component in our case of true carcinosarcoma is derived from mesenchymal transformation (metaplasia) of the squamous carcinoma cells. The findings were discussed in light of the previous pertinent literature. 相似文献
94.
Electrical polarization of plasma-spray-hydroxyapatite coatings for improvement of osteoconduction of implants 总被引:1,自引:0,他引:1
Kato R Nakamura S Katayama K Yamashita K 《Journal of biomedical materials research. Part A》2005,74(4):652-658
We have established the electrical polarization method of hydroxyapatite (HA) coatings (HAC) for clinical use, such as dental and orthopedic implants. The HAC examined in the current study was prepared in titanium substrates by plasma spraying of beta-tricalcium phosphate (TCP) powders followed by hydrothermal treatment. The prepared HAC consisted of a single phase of HA, because the starting TCP phase was completely transformed to the HA phase during the posthydrothermal treatment. Polarization was carried out at the elevated temperature of 400 degrees C under a d.c. field of 1 kV . cm(-1). The electrical measurements showed that the stored charges of the polarized HAC were greater than the reported value of the sintered ceramic HA. The enhanced bioactivity of the polarized HAC was demonstrated using 1.5 simulated body fluid (SBF). The crystal growth from the SBF solution was accelerated on the negatively charged surface in comparison with the untreated HAC. Similar to the polarized ceramic HA, the current results confirmed that the bioactivity of HAC would be effective for improving the initial fixation by polarization. 相似文献
95.
Suppressive effect of hyperbaric oxygenation on immune responses of normal and autoimmune mice. 总被引:4,自引:0,他引:4
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We studied the effect of hyperbaric oxygenation (HBO) on immune responses in normal and autoimmune mice. Mice were exposed to HBO in an animal chamber at a pressure of 252.5 kPa for 1 h and once a day for 5 days. The immunization of C3H/He mice with sheep erythrocytes induced marked anti-sheep erythrocyte antibody response on day 7. However, this response was markedly suppressed in HBO-treated mice. The suppression is dependent on the duration of HBO and it works on the early and the late stage of antibody responses. HBO suppresses the development of both sheep erythrocyte-specific B cells and helper T cells after the immunization. Then, we tried to expose autoimmune mice to HBO. Spontaneous immunoglobulin production of NZB and MRL/lpr spleen cells was also significantly suppressed by HBO. Furthermore, long term HBO exposure results in the suppression of the development of autoimmune symptoms such as proteinuria, facial erythema and lymphadenopathy in MRL/lpr mice. All these results suggest that HBO is applicable for the treatment of autoimmune diseases. 相似文献
96.
Hiroto Yamashita Shiro Noguchi Iwao Nakayama Hiroshi Togon Akira Moriuchi Shigeo Yokoyama Yuichi Mochizuki Akito Noguchi 《Pathology international》1984,34(1):123-132
A case of nonfunctioning parathyroid carcinoma in a 69-year-old female has been studied by light and electron microscopy. The tumor, located on the left side of the anterior neck, was well encapsulated by connective tissue but showed invasion to the capsule and to the thyroid. The tumor cells exhibited a trabecular arrangement surrounded by capillary networks but focally showed several ductal structures. They were polygonal in shape, had a large nucleus showing frequent mitosis and poor cytoplasm containing glycogen. Some tumor cells had clear and abundant cytoplasm, and resembled water-clear cells of the parathyroid. Immunohistochemically, no thyroglobulin was demonstrated in the tumor tissue. Electronmicroscopically, the tumor cells with high N/C ratio contained poorly developed cell organelles and abundant glycogen particles. They were poor in secretory granules and had no conglomeration of lipid. Desmosomes and tonoflbrils were observed. The ratio of the reported number of nonfunctioning parathyroid carcinoma to that of functioning one in Japan was compared with that in western countries. No difference of the ratio was found between these two, when identical criteria were employed. 相似文献
97.
B. M. Jiang H. Tsunemitsu Y. Qian K. Y. Green M. Oseto Y. Yamashita Linda J. Saif 《Archives of virology》1992,126(1-4):45-56
Summary Two partial cDNA clones of genes 5 (encoding the major inner capsid protein VP 6) and 6 (encoding a nonstructural protein) of the porcine group (Gp) C rotavirus (Cowden strain) were radiolabeled with32P and used individually as probes in Northern and dot blot hybridization assays. The specificity of each probe was tested against genomic dsRNA from: (1) porcine Gp A, B, and C rotaviruses; (2) Gp C rotaviruses from different species; and (3) porcine Gp C rotavirus field strains with varying electropherotype patterns. Neither probe hybridized with ds RNA from the porcine Gp A and B strains under the stringency conditions employed in the study. However, the gene 5 probe hybridized with the corresponding gene from the homologous porcine and the heterologous human and bovine Gp C rotaviruses tested. The gene 6 probe hybridized with the corresponding gene from the homologous Cowden strain, but hybridized weakly with gene 6 from the human and bovine Gp C rotaviruses. Both probes recognized all six different porcine Gp C field strains, although with varying intensities. Our results demonstrate that the gene 5 and 6 probes used in this study are specific for Gp C rotaviruses. However, evidence for greater genetic variation in the gene 6 among porcine, bovine and human Gp C strains suggested that the gene 5 probe may prove more broadly reactive among Gp C strains from different species. cDNA probes used in our study should prove useful for the detection of Gp C rotaviruses in feces and facilitate epidemiologic studies. 相似文献
98.
Multiple sensitivity of chorda tympani fibres of the rat and hamster to gustatory and thermal stimuli 总被引:5,自引:0,他引:5
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1. Impulse discharges in single chorda tympani fibres of rats and hamsters in response to gustatory stimuli representing the four basic qualities of taste as well as to cooling and warming of the tongue were recorded.2. In both rats and hamsters many fibres responded to more than one kind of gustatory stimulus as well as to thermal ones. The thermal sensitivity of these fibres was found to be about -0.5 impulses/sec. degrees C for cooling and 0.5 impulses/sec. degrees C for warming.3. Statistical calculations of the frequency of responses of chorda tympani fibres to single gustatory stimuli or combinations of stimuli were made, assuming that responsiveness to any one stimulus is independent of that to other stimuli. Evidence for relatively specific sensitivity to a particular stimulus or a particular combination of stimuli was obtained in the rat and the hamster.4. Across-fibre correlation coefficients between the amounts of responses to a pair of stimuli were calculated. In both the rat and the hamster, significant positive correlations were obtained with HCl, quinine and cooling. In addition, a positive correlation between sucrose and warming and a negative correlation between sucrose and NaCl were obtained in the hamster. The results are discussed in relation to the interaction of gustatory and thermal sensations of the human tongue. 相似文献
99.
Y. Kimura H. Aoki K. Shimokata Y. Ito Michiko Takano N. Hirabayashi E. Norrby 《Archives of virology》1979,61(4):297-304
Summary Experimental infection with HVJ (haemagglutinating virus of Japan—the Sendai strain of parainfluenza 1 virus) in mice was studied. Aerosol infection of newborn mice with the wild-type virus (HVJ-W) retarded the development of body weight and killed the animals within a few weeks. Large amounts of virus were isolated from both the lungs and the nasal turbinates of infected mice. In contrast, newborn mice exposed by inhalation to a temperature-sensitive(ts) mutant (HVJ-pB) derived from an HVJ carrier culture showed no clinical signs and grew equally well as mock-infected animals. No infectious virus could be recovered from the lungs although thets mutant grew to moderate titre in the nasal turbinates.The prior inoculation of newborn mice with thets mutant virus induced a state of significant resistance to subsequent challenge with the virulent wild-type virus.No replication of challenge virus in both lungs and nasal turbinates could be detected and the animals were protected a lethal infection. It is suggested that an avirulent temperature-sensitive mutant which has lost the capacity to replicate in the lower respiratory tract but is still capable of multiplying in the nasal turbinates may be a promising candidate for use in live vaccines especially against the infectious disease of the lower respiratory tract.With 2 Figures 相似文献
100.
The electrical activity of single neurones in the hypothalamic arcuate and supraoptic nuclei was recorded in urethane-anaesthetized rats. Stimulus pulses applied to the supraoptic nucleus antidromically activated 3 out of 41 cells recorded in the ipsilateral arcuate nucleus, confirming that there is a projection from the arcuate nucleus to the region of the supraoptic nucleus. Stimulation of the arcuate nucleus inhibited 17 out of 19 continuously firing (putative oxytocin) supraoptic neurones. Inhibition was followed by a marked post-stimulus excitation in 12 cells. The responses were not abolished by i.v. injection of the opioid antagonist naloxone. Thus at least part of the input to the magnocellular oxytocin system that arises from or passes through the arcuate nucleus, is not mediated by opioid peptides. 相似文献