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Background: The pathogenesis of multiple sclerosis (MS) is mediated primarily by T cells, but most studies of MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have focused on CD4+ T cells. The aims of the current study were to determine the pathological interrelationship between CD4 and CD8 autoreactive T cells in MS/EAE. Methods: Female C57BL/6 mice (n =20) were induced by myelin oligodendrocyte glycoprotein (MOG) 35-55 peptide. At 14 days after immunization, T cells were isolated from the spleen and purified as CD4+ and CD8 + T cells by using CD4 and CD8 isolation kits, and then the purity was determined by flow cytometric analysis. These cells were stimulated by MOG35–55 peptide and applied to proliferation assays. The interferon-gamma (IFN-γ) and interleukin (IL)-4 secretion of supernatant of cultured CD4 + and CD8 + T cells were measured by enzyme-linked immunosorbent assays (ELISA). For adoptive transfer, recipient mice were injected with MOG35–55-specific CD8+ or CD4+ T cells. EAE clinical course was measured by EAE score at 0–5 scale and spinal cord was examined by staining with hematoxylin and eosin and Luxol fast blue staining. Results: CD8+CD3+ and CD4+CD3 + cells were 86% and 94% pure of total CD3+ cells after CD8/CD4 bead enrichment, respectively. These cells were stimulated by MOG35–55 peptide and applied to proliferation assays. Although the CD8+ T cells had a generally lower response to MOG35–55 than CD4+ T cells, the response of CD8+ T cells was not always dependent on CD4. CD8+ T cell secreted less IFN-γ and IL-4 compared with CD4+ T cells. EAE was induced in wildtype B6 naive mice by adoptive transfer of MOG35–55-specific T cells from B6 active-induced EAE (aEAE) mice. A similar EAE score and slight inflammation and demyelination were found in naive B6 mice after transferring of CD8 + T cells from immunized B6 mice compared with transfer of CD4 + T cells. Conclusion: Our data suggest that CD8+ autoreactive T cells in EAE have a lower encephalitogenic function but are unique and independent on pathogenic of EAE rather than their CD4+ counterparts. Key words: Autoimmune; CD8-Positive T-Lymphocytes; Encephalomyelitis; Experimental; Multiple Sclerosis; Myelin-Oligodendrocyte Glycoprotein

A titanium alloy containing continuous oxygen gradient was prepared by powder metallurgy (P/M) and the composition–property relationship was studied on a single sample. The alloy was sintered with layered powder of different oxygen contents via vacuum sintering and spark plasma sintering (SPS), respectively. After subsequent heat treatments, high-throughput characterizations of the microstructures and mechanical properties by localized measurements were conducted. The Ti-7% Mo (molar fraction) alloy with an oxygen content ranging from 1.3×10−3 to 6.2×10−5 (mass fraction) was obtained, and the effects of oxygen on the microstructural evolution and mechanical properties were studied. The results show that SPS is an effective way for fabricating fully dense Ti alloy with a compositional gradient. The average width of α′ phase coarsens with the increase of the content of oxygen. The content of α″ martensitic phase also increases with the content of oxygen. At oxygen contents of 3×10−3 and 4×10−3 (mass fraction), the Ti alloys present the lowest microhardness and the lowest elastic modulus, respectively. The results also indicate that the martensitic phases actually decrease the hardness of Ti-7Mo alloy, and oxygen effectively hardens the alloy by solid solution strengthening. Therefore, the high-throughput characterization on a microstructure with a gradient content of oxygen is an effective method for rapidly evaluating the composition–property relationship of titanium alloys.

Titanium-based metal-metal composites show promises in many applications. In this work, iron-containing titanium-based composites were fabricated by using powder metallurgy method and rotary swaging process. Titanium-based composites with steel addition were sintered at temperature below Ti Fe eutectic temperature. Increase of the steel addition to 23% resulted in formation of Ti Fe intermetallic and density decrease in the composites. Further, the as-sintered composites present relatively good workability so hot rotary swaging of the as-sintered composites can be conducted. Steel particles were diffused into the Ti matrix and the composite transformed to a discontinuous β-Ti fiber-reinforced structure. As a result, mechanical properties (in axial direction) of the swaged composites were significantly improved. The tensile strength and elongation reached 1360 MPa and 9.3%, respectively.

ZnO nanorods were obtained by hydrothermal method using Zn (NO3)2 and N4(CH2)6 as raw materials, crystalline nanoplate ZnO grew on the columnar facets of the primary ZnO rods when citrate was introduced in the reaction system. The crystalling phase of ZnO particle was characterized by X-ray diffraction, the morphology was observed by SEM, the structure was indicated by FTIR. The result showed that the average nanoparticle diameter of ZnO was around 60 nm. Through the photocatalytic degradation of dibutyl phthalate (DBP) in aqueous solution under the illumination of UV light, nanoplate ZnO displayed high photocatalytic activity, the degradation efficiency was rising to 87.8% at 60 min illumination time.

To study the therapeutic effect of intraperitoneal hyperthermic double-distilled water and cis-diaminodichloro-platinum (DDP) perfusion for cancerous ascites and radical gastrectomy.LACA mice were injected peritoneally with H22 cancer cells (2 × 10(7) tumor cells). Five days later, the mice received treatments with either intraperitoneal perfusion of 37 °C isotonic fluid (group I), or 43 °C simple hyperthermic double-distilled water (group II), isotonic fluid (group III), DDP (group IV) or a combination of the hyperthermic double-distilled water with DDP (group V). A clinical experiment with intraperitoneal hyperthermic double-distilled water perfusion with DDP was carried out from September 1991 through September 1993 with 32 advanced gastric cancer patients who had undergone radical gastrectomy.In comparison with the untreated control group of cancer cell-bearing LACA mice, the mice in all treatment groups showed near complete obliteration of cancer cells in the peritoneal cavity, markedly reduced ascites, prolonged survival times, and reduced growth of peritoneal cancerous nodes. In the clinical experiment, all 32 patients with advanced carcinoma had achieved satisfactory results at the 1-year follow-up, but had unsatisfactory results at the 2-year follow-up.The intraperitoneal hyperthermic double-distilled water perfusion with DDP inhibited the occurrence of ascites in LACA mice bearing cancer cells, and prolonged the lifetime of patients with gastric cancer who had undergone radical gastrectomy.