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1.
The effect of human recombinant erythropoietin (Epo) on B cell responses was studied in a serum-free medium. Epo enhanced IgM production and thymidine uptake by a human IgM-producing lymphoblastoid cell line, CBL. This effect was specific to Epo since enhancement was blocked by anti-Epo antibody but not by control antibody. Among the various cytokines, interleukin-4 (IL-4) enhanced IgM production and thymidine uptake while IL-6 enhanced IgM production without affecting thymidine uptake. In contrast, other cytokines including IL-1 beta, IL-2, IL-5, interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), or granulocyte/macrophage colony-stimulating factor (GM-CSF) were without effect. However, the enhancing effect of Epo is different from that of IL-4 or IL-6, since Epo effect was not blocked by anti-IL-4 antibody or anti-IL-6 antibody. Moreover, specific binding of Epo was detected on CBL cells. Epo also enhanced immunoglobulin (IgG, IgM and IgA) production and thymidine uptake by purified tonsil small resting B cells stimulated by Staphylococcus aureus Cowan strain I (SAC) or by large activated B cells. In contrast, Epo had no effect on unstimulated small resting B cells. These results indicate that Epo could directly stimulate activated and differentiated B cells and could enhance B cell immunoglobulin production and proliferation.  相似文献   
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The effects of hindlimb unloading and recovery with or without running exercise on morphological and metabolic properties of soleus muscle fibers and their spinal motoneurons in rats were investigated. Ten-week-old rats were hindlimb suspended for 2 weeks and thereafter were rehabilitated with or without voluntary running exercise for 2 weeks. A decreased percentage of type I fibers and atrophy of all types of fibers were observed after hindlimb unloading. In addition, decreased oxidative enzyme activity of all types of fibers was observed after hindlimb unloading. In contrast, an improvement in the decreased percentage of type I fibers, decreased fiber cross-sectional area, and decreased fiber oxidative enzyme activity was observed after recovery with running exercise, but not without running exercise. There were no changes in the number, cell body size, or oxidative enzyme activity of motoneurons innervating the soleus muscle after hindlimb unloading or recovery with or without running exercise. These results indicate that running exercise is beneficial for the recovery of the decreased percentage of type I fibers and the atrophy and decreased oxidative enzyme activity of all types of fibers in the soleus muscle induced by hindlimb unloading and that there are no changes in morphological or metabolic properties of spinal motoneurons innervating the soleus muscle following decreased or increased neuromuscular activity.  相似文献   
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In this review we describe the methods and processes that our group have developed while aiming to test and design multiepitope vaccines for infectious diseases and cancer. Testing the performance of vaccines composed of epitopes restricted by human leukocyte antigen (HLA) molecules is accomplished by in vitro antigenicity assays, as well as in vivo immunogenicity assays in HLA transgenics. The efficiency by which multiepitope vaccines are processed is optimized by spacer residues, which are designed to facilitate generation by natural processing of the various class I- and class II-restricted epitopes. Methods and strategies to test and optimize HLA binding affinity, patient coverage from the vaccine construct, and TCR recognition of HLA/epitope complexes are also discussed.  相似文献   
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The effect of recombinant human erythropoietin (Epo) on plasma cells was studied in a serum-free medium, COSMEDIUM-001 (Cosmedium). Epo enhanced both Ig production and thymidine uptake by human plasma cell lines, AF-10 and IM-9. Interleukin-6 (IL-6) enhanced both Ig production and thymidine uptake by AF-10 and IM-9, while other cytokines, including IL-1 beta, IL-2, IL-3, IL-4, IL-5, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-alpha (IFN-alpha) or IFN-gamma, failed to do so. However, the Epo effect was specific since Epo-induced enhancement of Ig production and thymidine uptake was blocked by the anti-Epo antibody but not by the anti-IL-6 antibody or the control antibody. Conversely, IL-6-induced enhancement was blocked by the anti-IL-6 antibody but not by the anti-Epo antibody. Epo also enhanced Ig production (IgG, IgM, and IgA) and thymidine uptake by PCA-1+ plasma cells generated in vitro. This enhancement was also blocked by the anti-Epo antibody but not by the anti-IL-6 antibody. Taken together, these results suggest that Epo enhances plasma cell responses by a different mechanism than does IL-6.  相似文献   
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A 14-year-old girl was admitted to our hospital because of umbilical erythema and discharge. She had had an appendectomy at the age of twelve. Abdominal ultrasonography and cystoscopy revealed a large tumor-like mass at the posterior wall of the bladder. Computed tomography and magnetic resonance imaging revealed urachal sinus. The diagnosis of urachal abscess had been confirmed and conservative treatment had been continued by drainage via umbilicus and the administration of antibiotics. Total excision of the urachus was performed about one month later because the bladder mass was not reduced. Pathological findings revealed an inflammatory thickened wall of the urachus and no evidence of malignancy. We report this rare case of urachal abscess with a large mass in the retrovesical space.  相似文献   
8.
Abstract

Different approaches have been developed to improve the scaffold properties that provide structural support and biological interaction to achieve the desired environment for tissue regeneration. We previously reported that addition of human fibroblast growth factor 18 (hFGF18) to acryloyl group-modified cholesterol-bearing pullulan (CHPOA) nanogel-crosslinked (NanoClik) hydrogels that contain human bone morphogenetic protein 2 (hBMP2) stabilized bone healing in mouse calvarial defect model. In this study, we evaluated the use of disc-shaped dried nanogel-crosslinked gel as carriers of growth factors in order to seek possible clinical application in future. Both conventionally-dried NanoClik disc and nanogel-crosslinked porous (NanoCliP) disc made by freeze-drying that contained the growth factors induced bone healing but not as much as with NanoClik hydrogel application but addition of RGD peptides (RGD-NanoCliP disc) improved the healing. All type of discs showed the same biphasic ovalbumin-Alexa Fluor 488 protein release profile in vitro, an initial burst followed by a gradual sustained release more than one week, which was confirmed in vivo. Histological analysis showed remarkable new bone formation with more calcification in RGD-NanoCliP disc with the growth factors and the osteogenesis appeared to begin in the dura mater in contact with the disc. These observations suggest: (1) the fitness of the durable discs to the bone defect is a critical factor for bone healing, which is supplemented by addition of RGD peptides, (2) the porosity is suitable for osteoblast recruitment, (3) growth factor release pattern of the CHPOA nanogel based gels is ideal for bone healing.  相似文献   
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