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Endoscopic placement of metal stents are used widely for patients with esophageal obstruction and fistula due to progressive esophageal cancer, but cause high rate of severe complications associated with the immediate causes of death. To determine severe complications caused by stents, we studied clinical data and autopsy of six patients who had been treated with stents for inoperable progressive esophageal cancer. Occording to the clinical records only two patients had severe complications due to stents. But at autopsy, three patients had massive hemorrhage in the stent placement, one patient had mediastinitis, and one patient were in imminent danger of perforation whose stent had been incorporated into the adventitia of the wall. More severe complications were revealed than those expected clinically. Endoscopic placement of metal stents have a great deal for the improvement of quality of life. But we should carefully decide the indication because endoscopic placement of metal stents could cause severe complications associated with the immediate causes of death.  相似文献   
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Ligation of the chemokine receptor CCR2 on monocytes and macrophages with its ligand CCL2 results in activation of the cascade consisting of phosphatidylinositol-3-OH kinase (PI(3)K), the small G protein Rac and lamellipodium protrusion. We show here that a unique clathrin heavy-chain repeat homology protein, FROUNT, directly bound activated CCR2 and formed clusters at the cell front during chemotaxis. Overexpression of FROUNT amplified the chemokine-elicited PI(3)K-Rac-lamellipodium protrusion cascade and subsequent chemotaxis. Blocking FROUNT function by using a truncated mutant or antisense strategy substantially diminished signaling via CCR2. In a mouse peritonitis model, suppression of endogenous FROUNT markedly prevented macrophage infiltration. Thus, FROUNT links activated CCR2 to the PI(3)K-Rac-lamellipodium protrusion cascade and could be a therapeutic target in chronic inflammatory immune diseases associated with macrophage infiltration.  相似文献   
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In the regulation of host defense responses such as inflammation and immunity, the secretory proteins, including membrane proteins, play central roles. Although many secretory proteins have been identified by using methods such as differential display, random screening, or the signal sequence trap method, each method suffers from poor reproducibility, low sensitivity, or time-consuming or laborious work. Therefore, the strategy for facilitating the selection of the genes encoding the secretory proteins is desired. In this paper, we describe a system for isolating the genes encoding secretory proteins by analyzing mRNAs with microsomal fractionation on serial analysis of gene expression (SAGE)-based DNA microarray system. This system succeeded in discriminating the genes encoding secretory proteins from ones encoding nonsecretory proteins with 80% accuracy. We applied this system to human T lymphocytes. As a result, we were able to identify the genes that are not only encoding secretory proteins but also expressing selectively in a specific subset of T lymphocytes. The SAGE-based DNA microarray system is a promising system to identify the genes encoding specific secretory proteins.  相似文献   
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This study was designed to evaluate the histological changes during ossification and cellular events including osteogenic differentiation responding to collagenous bioresorbable membranes utilized for GBR. Standardized artificial bony defects were prepared at rat maxillae, and covered with a collagenous bioresorbable membrane. These animals were sacrificed at 1, 2, 3 and 4 weeks after the GBR-operation. The paraffin sections were subject to tartrate resistant acid phosphatase (TRAP) enzyme histochemistry and immunohistochemistry for alkaline phosphatase (ALP), osteopontin (OP) and osteocalcin (OC). In the first week of the experimental group, woven bone with ALP-positive osteoblasts occupied the lower half of the cavity. The collagenous membrane included numerous ALP-negative cells and OP-immunoreactive extracellular matrices. At 2 weeks, the ALP-, OP- and OC-immunoreactivity came to be recognizable in the region of collagenous membrane. Since ALP-negative soft tissue separated the collagenous membrane and the new bone originating from the cavity bottom, the collagenous membrane appeared to induce osteogenesis in situ. At 3 weeks, numerous collagen fibers of the membrane were embedded in the adjacent bone matrix. At 4 weeks, the membrane-associated and the cavity-derived bones had completely integrated, showing the same height of the periosteal ridge as the surrounding alveolar bones. The collagen fibers of a GBR-membrane appear to participate in osteogenic differentiation.  相似文献   
6.
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   
7.
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   
8.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
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