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81.
Murata K Inami M Hasegawa A Kubo S Kimura M Yamashita M Hosokawa H Nagao T Suzuki K Hashimoto K Shinkai H Koseki H Taniguchi M Ziegler SF Nakayama T 《International immunology》2003,15(8):987-992
CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients. 相似文献
82.
83.
Makito Hirano Hirohide Asai Takao Kiriyama Yoshiko Furiya Takaaki Iwamoto Tomohisa Nishiwaki Aya Yamamoto Toshio Mori Satoshi Ueno 《Neuroscience letters》2007
Early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH)/ataxia with oculomotor apraxia type 1 (AOA1) is caused by mutations in the gene encoding aprataxin (APTX). Although several in vitro findings proposed that impaired enzymatic activities of APTX are responsible for EAOH/AOA1, potential instability of mutant proteins has also been suggested as the pathogenesis based on in vivo finding that mutant proteins are almost undetectable in EAOH/AOA1 tissues or cells. The present study aimed to experimentally prove instability of mutant proteins in neuronal cells, the cell type preferentially affected by this disease. Results of pulse-chase experiments demonstrated that all of the disease-associated mutants had extremely shorter half-lives than the WT. We further found that mutants were targeted for rapid proteasome-mediated degradation. These results help establish pathogenic and physiological protein characteristics of APTX in neuronal cells. 相似文献
84.
A delayed-type inflammatory response was evoked in mice using concanavalin A (Con A) as a stimulus, and the effect of various anti-inflammatory agents on the inflammations was examined. The intraperitoneal injection of Con A in the mouse resulted in the marked accumulation of leukocytes, especially macrophages, in the peritoneal cavity between 16 and 48 hr after the injection. Prior to the accumulation of macrophages, the chemotactic activity for macrophages appeared in the peritoneal fluid, and was associated with protein(s) in the molecular weight range from 10000 to 100000 daltons. When the effect of various agents on Con A-induced peritonitis was examined, neither anticomplementary agents (FUT-175 and K-76 COONa), bromophenacyl bromide, nordihydroguaiaretic acid nor indomethacin affected the generation of chemotactic activity and the accumulation of macrophages, suggesting that C5a, prostaglandins and leukotriene B4 are hardly involved in the Con A-induced macrophage accumulation. On the other hand, dexamethasone suppressed both the generation of chemotactic activity and the accumulation of macrophages. Taking into consideration the observation that the synthesis of macrophage chemotactic factors by mitogen-stimulated lymphocytes is inhibited by glucocorticoids these results suggest that the macrophage chemotactic lymphokines might be involved in the accumulation of macrophages in Con A-induced peritonitis. 相似文献
85.
Yamashita H Noguchi Y Noguchi S Yamashita H Uchino S Watanabe S Ogawa T Murakami T 《Endocrine pathology》2005,16(1):41-48
Risk factors for distant metastasis were studied in 82 patients with follicular thyroid carcinoma (FTC). Metastases to either
the lung or bone existing at the time of presentation were confirmed by I-131 radio-iodine uptake in 10 patients. FTC with
an insular component was found in eight patients. Univariate analysis of 14 possible risk factors showed 7 to be statistically
significant: insular component, poorly differentiated carcinoma, trabecular component, serum thyroglobulin level before surgery,
patient age at the time of presentation, solid component, and vascular invasion (ranked by p values). After further analysis of the interrelation of the factors and of the logistic regression curves, we concluded that
presence of an insular component and patient age were the only independent risk factors. Distant metastasis was not detected
in any of the 27 patients ≤49 yr old. Among the 55 older patients (≥50 yr old), 5 of the 49 (10%) without an insular component
and 5 of the 6 (83%) with an insular component had distant metastasis. The remaining older patient with an insular component
but without distant metastasis showed a gradual increase in thyroglobulin levels after total thyroidectomy. 相似文献
86.
Yuya Yamashita Tetsuo Tsuda Hiroyasu Ishida Akihiko Uchikawa Yasuhisa Kuriyama 《Macromolecular chemistry and physics.》1968,113(1):139-146
The copolymerization behavior of β-propiolactone (PL) and α.α-bischloromethyl β-propiolactone (α-BCPL) is correlated with the mode of fission. With sodium acetate as catalyst, the formation of β-acetoxy propionic acid at the initiation reaction was observed and α-BCPL was more than five times as reactive as PL in copolymerization. Thus propagation by carboxylate anion through alkyl-oxygen fission was presumed in the case of pyridine and the acetate of Na, Li, and Mg as catalyst. On the other hand, the formation of ethyl β-hydroxy propionate and the decreased reactivity of α-BCPL in copolymerization was observed with magnesium and aluminum ethoxide as catalyst. In the case of the ethoxide of Na, Li, and Al, and Et2Mg or Et3Al as catalyst, propagation by alkoxide anions through acyl-oxygen fission of the coordinated lactones was presumed. 相似文献
87.
Shouji Iwatsuki Hideo Kasahara Yuya Yamashita 《Macromolecular chemistry and physics.》1967,104(1):254-262
RANEY metals (Ni, Fe, Co), URUSHIBARA metals (Ni, Co) and ULIMANN cu initiate the polymerization of methylmethacrylate. Diamines, diols or organic halides enhance their reactivity. In the presence of CCl4, the polymerization rate (Rp) is proportional to the square root of the amount of both metals and CCl4, and to the first power of the monomer concentration, but Rp becomes constant and independent of the concentration of CCl4 when there is a great excess of CCl4. We concluded that this polymerization follows the free radical mechanism and the participation of a zero-valent metal atom in the initiation reaction including complex formation between metal and CCL4 is suggested. 相似文献
88.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
89.
Tadaaki Yokota Yoshimi Yamashita Yoshiko Okuzono Mutsuo Takahashi Shigeyoshi Fujihara Shin'ichiro Akizuki Tokuhiro Ishihara Fumiya Uchino Takako Iwata 《Pathology international》1984,34(3):663-668
A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984. 相似文献
90.
Yamada H Kuroda E Matsumoto S Matsumoto T Yamada T Yamashita U 《Clinical and experimental immunology》2002,128(1):52-58
The regulatory effect of prostaglandin (PG) E2 and a cyclooxygenase (COX) inhibitor on Bacille Calmette-Guérin (BCG)-induced macrophage cytotoxicity in a bladder cancer cell, MBT-2, was studied in vitro. BCG stimulated thioglycollate-elicited murine peritoneal exudate cells (PEC) to induce cytotoxic activity and to produce cytokines such as interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and PGE2. NS398, a specific COX-2 inhibitor, and indomethacin (IM), a COX-1 and COX-2 inhibitor, enhanced viable BCG-induced cytotoxic activity and IFN-gamma and TNF-alpha production of PEC. However, NS398 and IM did not enhance these activities induced by killed BCG. Enhanced cytotoxicity was mediated by increased amounts of IFN-gamma and TNF-alpha. Exogenous PGE2 reduced cytotoxic activity and IFN-gamma and TNF-alpha production of PEC. These results suggest that PGE2 produced by BCG-activated macrophages has a negative regulatory effect on the cytotoxic activity of macrophages. Accordingly, a PG synthesis inhibitor may be a useful agent to enhance BCG-induced antitumour activity of macrophages. 相似文献