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Di Liu

Publications and source records attributed to Di Liu.

21 records · Page 2Linked to original sources

Depletion of collagen II-reactive T cells and blocking of B cell activation prevents collagen II-induced arthritis in DBA/1j mice.

Collagen II (CII)-induced arthritis in DBA/1j mice is mediated by both CII-reactive T cells and anti-CII Ab-producing B cells. To determine the relative role of these processes in the development of arthritis, we specifically eliminated CII-reactive T cells by treating the mice with CII-pulsed syngeneic macrophages that had been transfected with a binary adenovirus system. These macrophages express murine Fas ligand in a doxycycline-inducible manner with autocrine suicide inhibited by concomitant expression of p35. The mice were treated i.v. with four doses of CII-APC-AdFasLp35Tet or a single dose of AdCMVsTACI (5 x 10(9) PFU), or both simultaneously, beginning 2 wk after priming with CII in CFA. Treatment with CII-APC-AdFasLp35Tet alone or in combination with a single dose of AdCMVsTACI prevented the development of CII-induced arthritis and T cell infiltration in the joint. The elimination of T cells was specific in that a normal T cell response was observed on stimulation with OVA after treatment with CII-APC-AdFasLp35Tet. Treatment with AdCMVsTACI alone prevented production of detectable levels of circulating anti-CII autoantibodies and reduced the severity of arthritis but did not prevent its development. These results indicate that the CII-reactive T cells play a crucial role in the development of CII-induced arthritis and that the anti-CII Abs act to enhance the development of CII-induced arthritis.

Adenoviridae↗

[Effect of Angelica sinensis polysaccharides on lymphocyte proliferation and induction of IFN-gamma].

AIM: To study the effect of Angelica sinsensis polysaccharides on lymphocyte proliferation and induction of IFN-gamma. METHODS: Angelica sinensis polysaccharides(AP) were separated into AP-I, AP-II, AP-III and AP-IV by alcohol deposition with different concentration. The radioactivities of [3H]-TdR uptake by lymphocyte were used to determine the ability of lymphocyte. The bioactivity of IFN-gamma was measured by violet crystalline dying. RESULTS: AP-IV was found to be composed of Ara and Glu in the ratio of 0.99:6.47, the molecular weight was estimated to be 5,600. AP-I and AP-II 100 mg.kg-1 i.p. were found to significantly augment mice splenocyte proliferation, release IFN-gamma and increase IFN-gamma bioactivity. 50 micrograms.mL-1 AP-I, AP-II and AP-III were shown to enhance the proliferative response of the mouse spleen lymphocytes in vitro. CONCLUSION: AP-I and AP-II showed higher immunoactivity than AP-III, AP-IV had no effect.

Angelica sinensis↗

[Study on the fluctuation phenomena of arc plasma spraying jet].

The turbulence phenomenon is one of the most attractive characteristics of a DC arc plasma spraying jet. Most of the previous investigations believe that there is a laminar flow region in core of the jet. A spectrum diagnostic system has been built up in this paper to investigate these effects with the aid of high-speed digital camera. The FFT method has been applied to the analysis on the arc voltage and light signals. The influence of the arc behavior and the power supply on the jet is full-scale. It seems that there is not a laminar flow region in core of the jet. Moreover, from the light dynamic variation graph, the jet fluctuation due to the arc voltage behavior maybe is the dominant characteristic of the jet behavior.

English Abstract↗