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71.
Michimasa Ebato Taizo Nitta Hideo Yagita Kiyoshi Sato Ko Okumura 《European journal of immunology》1994,24(12):2987-2992
The purpose of this study was to assess the V-(D)-J junctional region of the T cell receptor (TCR), the CDR3 region, which is responsible for glioma-specific antigen contact in αβ TCR-mediated recognition. We sequenced the TCR α and β chians of Vα7, and Vβ13.1 cDNA derived from tumor-infiltrating lymphocytes (TIL) of 12 glioma patients and also the corresponding clones from the patients' peripheral blood lymphocytes (PBL). A shared Vβ13.1 DJ sequence of the CDR3 region, NDβN, was demonstrated in 49 of 66 Vβ13.1+ clones (74.2 %) from the glioma TIL, whereas only 4 of 33 clones (12.1 %) were observed in the Vβ13.1+ clones from the PBL (p < 0.001). A common VDJ sequence, FCASS (Vβ13.1)-YRLPWGTSDS (NDβN)-GELFF(Jβ2.2), was observed not only in the gliomas from each patient, but also among all the patients with a preference for Vβ13.1. In contrast, the amino acid sequences of the Vβ13.1+ PBL clones were diverse and random. Next, we sequenced subclones from other Vβ subfamilies randomly selected to compare their VDJ region rearrangements (Vβ3 and Vβ5.1). In contrast to Vβ13.1, the amino acid sequences of these junctional regions were completely different in these subclones. The V-J junctional region of the α chain is dominated by a few clones in some patients, and no shared amino acid sequences were detected in the TCR Vα junctional region. However, in the Nα region of the Vα7-bearing TIL clones, arginine was used in 27 of 44 clones (61.4%) compared to only 3 of 12 clones from the PBL (p < 0.05). These results are consistent with the hypothesis that a clonal expansion/accumulation of glioma lineage-specific T cells occurred in vivo at the tumor site and that these T cells may be recognizing glioma-specific antigens. 相似文献
72.
Kiyoshi Takahashi Naorni Sakashita Yukio Ando Moritaka Suga Masayukl Ando 《Pathology international》1997,47(6):353-359
Clinicopathological features of three autopsy cases of extremely rare late onset type I familial amyloldotic polyneuropathy were presented and compared with 19 autopsy cases of the ordinary type. In the late onset cases, the ages at onset and at death were 27.5 and 24.5 years older, respectively, compared with the ordinary type. Also, duration of the total clinical course form onset to death was 3.7 years less than in the late onset cases. The degree of amyloid deposition was more marked in the heart of the late onset cases, causing prominent cardiac hypertrophy. It was also marked In the kidneys or thyroid of two cases, but slight to moderate in the peripheral or autonomic nervous tissues in all cases. Immunohistochemical Investigation demonstrated the presence of transthyretin (TTR) as an amyloid precursor protein and of serum amyloid P-component in amyloid deposits in various organs and tissues of the late onset type. These findings, as well as serum levels of variant TTR, were similar to those of the ordinary type. These results suggest that there are some factors other than the amyloid precursor protein that effect the degree of amyloid deposition. 相似文献
73.
74.
Wakamatsu T Saito T Hayashi J Takeichi T Kitamoto K Aizawa K 《Medical molecular morphology》2005,38(4):225-232
Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the
long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional
injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg,
was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength
664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised
and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the
balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated
arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in
the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was
repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit
restenosis after vascular intervention.
An erratum to this article is available at . 相似文献
75.
76.
Hidai C Kawana M Habu K Kazama H Kawase Y Iwata T Suzuki H Quertermous T Kokubun S 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,287(2):1165-1175
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery. 相似文献
77.
Schultz MJ Knapp S Florquin S Pater J Takeda K Akira S van der Poll T 《Infection and immunity》2003,71(4):1630-1634
Interleukin-18 (IL-18) is a potent cytokine with many different proinflammatory activities. To study the role of IL-18 in the pathogenesis of Pseudomonas pneumonia, IL-18-deficient (IL-18(-/-)) and wild-type mice were intranasally inoculated with Pseudomonas aeruginosa. IL-18 deficiency was associated with reduced outgrowth of Pseudomonas in the lungs and diminished dissemination of the infection. In addition, pulmonary inflammation (histopathology) and levels of tumor necrosis factor alpha, IL-6, and macrophage inflammatory protein-2 in lungs and plasma were lower in IL-18(-/-) mice. Consistent with results obtained for IL-18(-/-) mice, treatment of wild-type mice with a neutralizing IL-18 binding protein-immunoglobulin G Fc fusion construct also attenuated outgrowth of Pseudomonas compared with that for mice treated with a control protein. These results demonstrate that the presence of endogenous IL-18 activity facilitates inflammatory responses in the lung during Pseudomonas pneumonia, concurrently impairing bacterial clearance. 相似文献
78.
Protective role of heme oxygenase-1 in renal ischemia 总被引:3,自引:0,他引:3
Oxidative stress, which has been implicated in the pathogenesis of ischemic renal injury, degrades heme proteins, such as cytochrome P450, and causes the elevation in the level of cellular free heme, which can catalyze the formation of reactive oxygen species. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is induced not only by its substrate, heme, but also by oxidative stress. In various models of oxidative tissue injuries, the induction of HO-1 confers protection on tissues from further damages by removing the prooxidant heme, or by virtue of the antioxidative, antiinflammatory, and/or antiapoptotic actions of one or more of the three products, i.e., carbon monoxide, biliverdin IXalpha, and iron by HO reaction. In contrast, the abrogation of HO-1 induction, or chemical inhibition of HO activity, abolishes its beneficial effect on the protection of tissues from oxidative damages. In this article, we review the protective role of HO-1 in renal ischemic injury, and its potential therapeutic applications. In addition, we summarize recent findings in the regulatory mechanism of ho-1 gene expression. 相似文献
79.
Kiyoshi Tanikawa Takamichi Enomoto Masahiro Hatano Keiko Motegi Zenjiro Okuno 《Macromolecular chemistry and physics.》1975,176(10):3025-3034
Poly(N-vinylcarbazole), (PNVC), was prepared, fractionated by gel permeation chromatography, and then characterized by viscometry and vapour pressure osmometry. The fractionated PNVC species with relatively narrow molecular weight distributions were successfully used to measure both their electrical dark-conductivity and photoconductivity using a surface type cell in high vacuum (ca. 10?7 mm Hg) at room temperature. A molecular weight dependent photoconductivity was found for the fractionated PNVCs with weight average molecular weights in the range of 1,2·103 to 2,4·105. This observation is in contradiction to Epping's results who has found a molecular weight independent photoconductivity in the molecular weight range of 3·105 to 7·106. Our molecular weight dependence may be well understood in terms of the interrupted overlap of the π-electrons of adjacent carbazolyl groups at the terminal parts of the polymer chains, this effect being all the more stronger the smaller the molecular weight is. 相似文献
80.
In order to investigate the role of monocyte/macrophages and their relationship to the expression of macrophage colony-stimulating factor (MCSF) in pulmonary atherosclerosis, lungs were excised from rabbits that had been fed for 60 and 90 days on a diet containing 0.5% cholesterol. In the lungs, fatty streaks and elevated foam cell lesions predominated in the large or medium-sized elastic pulmonary arteries, while massive accumulation of foam cells in the intima of muscular arteries produced marked luminal narrowing and nearly complete occlusion. In these lesions, most of the foam cells were reactive with RbM2, a monoclonal antibody (mAb) against rabbit macrophages, while smooth muscle cell-derived foam cells were detected by mAb against smooth muscle actin in the deeper area of elevated foam cell lesions of elastic arteries. Ultrastructural observation confirmed the presence of monocytes in the intima, their differentiation into macrophages, and their transformation into foam cells in the atherosclerotic lesions. lmmunohistochemical expression of MCSF was demonstrated in the endothelial cells, smooth muscle cells and foam cells. A minor macrophagederived foam cell population was demonstrated to possess a prolif-erative capacity. These data suggest that MCSF is involved in the differentiation of monocytes into macrophages, their transformation into foam cells, and their proliferation during pulmonary atherogenesis. 相似文献