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Surface modification of poly(lactic acid) (PLA) film is performed via 172 nm excimer lamp irradiation. Effects on water vapor solubility and physical properties via vacuum ultraviolet (VUV) irradiation are studied systematically. After VUV irradiation, water vapor solubility increases approximately 11–43% in the low‐pressure region and approximately 20–38% in the high‐pressure region as surface hydrophilicity increased. The increase is attributed to hydrogen bonding with the carboxyl groups because of VUV radiation. The modified layer is significantly swelling after water vapor sorption. The hydrophilic layer forms a thickness of 2–3 μm from the irradiated surface via VUV radiation, but no changes are observed inside the irradiated film. Therefore, PLA film solubility after irradiation is enhanced by hydrophilicity and the swelling effect of the surface. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42200.  相似文献   
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Osteoarthritis (OA) occurs not only in the knee but also in peripheral joints throughout the whole body. Previously, we have shown that the expression of cellular communication network factor 3 (CCN3), a matricellular protein, increases with age in knee articular cartilage, and the misexpression of CCN3 in cartilage induces senescence-associated secretory phenotype (SASP) factors, indicating that CCN3 promotes cartilage senescence. Here, we investigated the correlation between CCN3 expression and OA degenerative changes, principally in human femoral head cartilage. Human femoral heads obtained from patients who received total hip arthroplasty were categorized into OA and femoral neck fracture (normal) groups without significant age differences. Gene expression analysis of RNA obtained from femoral head cartilage revealed that CCN3 and MMP-13 expression in the non-weight-bearing part was significantly higher in the OA group than in the normal group, whereas the weight-bearing OA parts and normal cartilage showed no significant differences in the expression of these genes. The expression of COL10A1, however, was significantly higher in weight-bearing OA parts compared with normal weight-bearing parts, and was also higher in weight-bearing parts compared with non-weight-bearing parts in the OA group. In contrast, OA primary chondrocytes from weight-bearing parts showed higher expression of CCN3, p16, ADAMTS4, and IL-1β than chondrocytes from the corresponding normal group, and higher ADAMTS4 and IL-1β in the non-weight-bearing part compared with the corresponding normal group. Acan expression was significantly lower in the non-weight-bearing group in OA primary chondrocytes than in the corresponding normal chondrocytes. The expression level of CCN3 did not show significant differences between the weight-bearing part and non-weight-bearing part in both OA and normal primary chondrocytes. Immunohistochemical analysis showed accumulated CCN3 and aggrecan neoepitope staining in both the weight-bearing part and non-weight-bearing part in the OA group compared with the normal group. The CCN3 expression level in cartilage had a positive correlation with the Mankin score. X-ray analysis of cartilage-specific CCN3 overexpression mice (Tg) revealed deformation of the femoral and humeral head in the early stage, and immunohistochemical analysis showed accumulated aggrecan neoepitope staining as well as CCN3 staining and the roughening of the joint surface in Tg femoral and humeral heads. Primary chondrocytes from the Tg femoral head showed enhanced expression of Ccn3, Adamts5, p16, Il-6, and Tnfα, and decreased expression of Col2a1 and -an. These findings indicate a correlation between OA degenerative changes and the expression of CCN3, irrespective of age and mechanical loading. Furthermore, the Mankin score indicates that the expression level of Ccn3 correlates with the progression of OA.  相似文献   
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BACKGROUND: The recent recognition of the association of Epstein-Barr virus (EBV) with T-cell/natural killer cell (T/NK-cell) lymphoma has documented that particular types of EBV-containing T/NK-cell lymphoma are frequently complicated by hemophagocytic syndrome (HPS). This observation suggests that both EBV and proliferating T/NK-lymphoma cells play significant roles in the development of HPS. Cytokines released from neoplastic T cells are presumed to account for the activation of macrophages, which is followed by a complex cascade of cytokine production, resulting in full-blown HPS. Five patients with B-cell lymphoma complicated by HPS were studied for elevated serum cytokines, the association of EBV, and CD25 expression of lymphoma cells; the aim of this study was to verify whether the mechanisms of HPS development hypothesized for T/NK-cell lymphoma also operate in B-cell lymphoma. METHODS: Sera were analyzed for the presence of inflammatory and immunoregulatory cytokines. Flow cytometry, immunohistology (IH), in situ hybridization (ISH), polymerase chain reaction (PCR), and Southern blot analysis were performed using bone marrow aspirates, biopsy specimens, and autopsy specimens. RESULTS: Immunophenotypic and Southern blot studies verified that the lymphoma cells of all five patients were of B-cell lineage. Bone marrow aspirates demonstrated histiocytosis with extensive hemophagocytic activity. Marked elevation of serum cytokines and expression of CD25 were observed in all five patients. However, the results of PCR, ISH using EBER1 probe, and IH for latent membrane protein indicated that these lymphoma cells were free of EBV infection. CONCLUSIONS: In patients with B-cell lymphoma, EBV infection is not necessarily required for the initiation of HPS. In this article, the pathogenesis of HPS assumed to be operative in B-cell lymphoma is discussed with reference to T/NK-cell lymphoma complicated by HPS.  相似文献   
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Dialysis membrane was prepared by a phase inversion method using a new polyether-segmented nylon which dissolves in common organic solvents such as dimethylsulfoxide. The polyether-segmented nylon contained poly(ethylene oxide) block and nylon block (random copolyamide: Ny69/M10) prepared by sebacic acid, azelaic acid, m-xylenediamine, and hexamethylenediamine. The morphologies and permeability characteristics of the membranes were investigated. It was shown by scanning electron microscope observation that the membrane had a fingerlike structure when dimethylsulfoxide was used as a polymer solvent, and a spongelike structure when an additive such as calcium chloride was added to the polymer solution. The high permeability for the solutes such as urea and vitamin B12 were observed in comparison with the polyether-segmented Ny610 membranes prepared by a phase inversion method. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1731–1737, 1997  相似文献   
6.
The recent identification of two mannose-binding lectin-associated serine protease clones from Halocynthia roretzi, an ascidian, suggested the presence of a complement system in urochordates. To elucidate the structure and function of this possibly primitive complement system, we have isolated cDNA clones for ascidian C3 (AsC3) and purified AsC3 protein from body fluid. The deduced primary structure of AsC3 shows overall similarity to mammalian C3, including a typical thioester site with the His residue required for nucleophilic activation of the thioester. AsC3 has a two-subunit chain structure, and the alpha-chain is cleaved at a specific site near to the N terminus upon activation. Ascidian body fluid contains an opsonic activity which enhances phagocytosis of yeast by ascidian blood cells, and Ab against AsC3 inhibits this opsonic activity. These results indicate that the complement system played a pivotal role in innate immunity by enhancing phagocytosis before the emergence of the vertebrates and well ahead of the establishment of adaptive immunity, which is believed to have occurred at about the time of the appearance of cartilaginous fish.  相似文献   
7.
Creep tests have been correlated with microstructural changes which occurred during creep of Inconel 617 at 1000 °C, 24.5 MPa. The following results were obtained: 1) Fine intragranular carbides which are precipitated during creep are effective in lowering the creep rate during the early stages of the creep regime (within 300 h). 2) Grain boundary carbides migrate from grain boundaries that are under compressive stress to grain boundaries that are under tensile stress. This is explained in terms of 1 the dissolution of relatively unstable carbides on the compressive boundaries, 2 the diffusion of the solute atoms to the tensile boundaries and 3 the reprecipitation of the carbides at the tensile boundaries. The rate of grain boundary carbide migration depends on grain size. 3) M23C6 type carbides, having high chromium content, and M6C type carbides, having high molybdenum content, co-exist on the grain boundaries. M23C6 type carbides, however, are quantitatively predominant. Furthermore, M6C occurs less frequently on the tensile boundaries than on the stress free grain boundaries. This is attributed to the difference of the diffusion coefficients of chromium and molybdenum. 4) The grain boundaries on which the carbides have dissolved start to migrate in the steady state creep region. The creep rate gradually increases with the occurrence of grain boundary migration. 5) The steady state creep rate depends not so much on the morphological changes of carbides as on the grain size of the matrix.  相似文献   
8.
Male (NZW x BXSB)F1 mice spontaneously develop a disease which closely resembles human systemic autoimmune disease, involving idiopathic thrombocytopenic purpura and glomerulonephritis. We investigated whether autoimmune thrombocytopenia in the mice responded to deoxyspergualin, as immunosuppressant. Deoxyspergualin completely prevented the development of thrombocytopenia and suppressed the increase in circulating autoantibodies against platelets. This agent also ameliorated lupus nephritis. These findings suggest that deoxyspergualin may be effective in the prevention of idiopathic thrombocytopenic purpura.  相似文献   
9.
We encountered two unusual cases of intrapulmonary teratoma, one in a 31-year-old female and the other in a 15-year-old female. The chief complaint of both patients was fever, and in both a consolidation was detected in the left upper lobe using routine radiography. We performed left upper lobectomy for the former patient and segmentectomy of the left lingual segment for the latter. Neither tumor communicated with the mediastinum. Histological examination revealed a pulmonary teratoma containing no thymic tissue in both. Intrapulmonary teratoma has been reported to be extremely rare, and only 27 cases including these two have been reported in the literature.  相似文献   
10.
The relationships between the morphologies and the permeability characteristics as dialysis membrane of polyether-segmented nylon 610 (PE-Ny610) have been investigated. PE-Ny610 used are poly(propylene oxide) (PPO)-segmented nylon 610 containing 25 wt % PPO (PPO-Ny610) and poly(ethylene oxide) (PEO)-segmented nylon 610 containing 15 wt % PEO (PEO-Ny610). The morphologies in the cross section of the membranes exhibit the cellular porous structures due to liquid-liquid phase separation. On the other hand, the structures of the surfaces are mainly composed of the crystalline spherulite due to liquid-solid phase separation. These morphologies are little affected by the composition ratio of the coagulant, calcium chloride/methanol/water mixture. PEO-Ny610 membranes have shown superior membrane performances to the PPO-Ny610 membrane. The effect of PEO content in PEO-Ny610 on the adhesion of platelet onto the PEO-Ny610 film surface was investigated and it is concluded that PEO-Ny610 having > 10 wt % PEO shows a good nonthrombogenicity equal to PPO-Ny610. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1713–1721, 1997  相似文献   
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