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Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX–PMB and OMe-PRX–PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX–PMB surface much more than PRX–PMB and PMB-block–PEG–block-PMB (PEG–PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG–PMB, PRX–PMB, and OMe-PRX–PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX–PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces.  相似文献   
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Background Recommendations for diagnosis and treatment of gastric borderline (group III) lesions remain controversial. We examined mucin expression patterns in endoscopically resected and forceps biopsy samples. Methods Sixty-three gastric lesions were histopathologically identified as belonging to group III on the basis of an endoscopic forceps biopsy. All of the patients underwent endoscopic resection, and the lesions were classified into group A (final diagnosis, adenocarcinoma) or group B (final diagnosis, adenoma). Immunostaining for MUC2, MUC5AC, MUC6, and CD10 was performed and the mucin phenotype determined. An additional 26 forceps biopsy samples from the above 63 patients were similarly evaluated. Results The proportion of complete gastric (positive for MUC5AC and MUC6) plus gastric-predominant phenotypes was significantly higher in group A (58.0%) than in group B (18.7%) lesions (P < 0.05). The proportion of the complete intestinal (positive for MUC2 and CD10) phenotype was significantly higher in group B (68.8%) than in group A (19.4%) (P < 0.05). Similar results were also observed in the 26 forceps biopsy samples histopathologically diagnosed as group III lesions. The proportion of samples with a diffuse Ki-67 immunostaining pattern was significantly higher in group A than in group B (P < 0.05). p53 expression was significantly higher in group A (29.2%) than in group B (4.3%) (P < 0.05). Conclusions Immunostaining of forceps biopsy samples for the mucin phenotype may be helpful for diagnosing gastric borderline (group III) lesions.  相似文献   
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The present study was performed to examine whether the expression of CD64 Fc gamma receptor type I (FcgammaRI) on both neutrophils and monocytes can be modulated by multiple daily administrations of granulocyte colony-stimulating factor (G-CSF) to patients with non-Hodgkin's lymphoma in neutropenia caused by CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. The expression of CD64 was determined by flow cytometric analysis at the following time points: before chemotherapy, at the nadir of the neutrophil count, at the fifth day after the start of G-CSF administration, and at more than 8 days after the start of G-CSF administration. CD64 expression was enhanced in patients given G-CSF during CHOP treatment, whereas CD64 expression remained unchanged in patients not given G-CSF CD64 expression levels on both neutrophils and monocytes were significantly up-regulated by the daily administration of G-CSF and reached peak levels at day 5 (P = .0007). Thereafter, expression on both cell types remained at almost the same levels as on day 5 for the rest of the treatment course, even though G-CSF therapy continued for 3 to 5 more days. Interestingly, CD64 expression on monocytes was already increased significantly (P = .0001) at the nadir of the neutrophil count relative to the baseline before chemotherapy and then was additionally up-regulated by day 5 after the start of G-CSF injections (P = .019). In antibody-dependent cellular cytotoxicity assays, we found that rituximab-mediated cell lysis was significantly enhanced at day 5 after the start of G-CSF treatment (P = .01). In conclusion, this study shows that multiple doses of G-CSF administered to lymphoma patients with neutropenia due to CHOP chemotherapy can enhance CD64 expression on both neutrophils and monocytes. Peak CD64 levels are reached at day 5 of G-CSF treatment, resulting in an activation of the rituximab-mediated antitumor ability of these effector cells. This finding may be useful in determining the optimal timing of administration for an antibody such as rituximab in a chemotherapeutic strategy designed to exert a maximal effect against tumor cells.  相似文献   
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The treatment of patients with aggressive subclasses of myelodysplastic syndrome (MDS) remains a challenge. In an effort to improve the survival of patients with refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), or acute myelogenous leukemia transformed from MDS (MDS-AML), we conducted a small trial in which 28 such patients were treated with low-dose cytosine arabinoside (LDAraC) followed by administration of macrophage colony-stimulating factor (M-CSF). The overall rate of response to the treatment was 61%, including 39% with a complete response, which is higher than rates obtained in previous studies in which LDAraC alone was administered to patients with MDS. Median survival was 23.5 months in cases of RAEB, 16.7 months in cases of RAEB-t, and 19.7 months in cases of MDS-AML. The overall survival of the study group appeared to be prolonged in comparison with a historical control group of patients treated with LDAraC alone. It is suggested that M-CSF added to the administration of LDAraC plays an active role in the therapy. No therapy-related death occurred. Some unique actions of M-CSF were suggested in this trial. It is concluded that therapy with LDAraC + M-CSF is a useful treatment option for patients with aggressive subclasses of MDS and MDS-AML to provide better response and survival.  相似文献   
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