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Indoleamine 2,3-dioxygenase is a signaling protein in long-term tolerance by dendritic cells 总被引:1,自引:0,他引:1
Pallotta MT Orabona C Volpi C Vacca C Belladonna ML Bianchi R Servillo G Brunacci C Calvitti M Bicciato S Mazza EM Boon L Grassi F Fioretti MC Fallarino F Puccetti P Grohmann U 《Nature immunology》2011,12(9):870-878
Regulation of tryptophan metabolism by indoleamine 2,3-dioxygenase (IDO) in dendritic cells (DCs) is a highly versatile modulator of immunity. In inflammation, interferon-γ is the main inducer of IDO for the prevention of hyperinflammatory responses, yet IDO is also responsible for self-tolerance effects in the longer term. Here we show that treatment of mouse plasmacytoid DCs (pDCs) with transforming growth factor-β (TGF-β) conferred regulatory effects on IDO that were mechanistically separable from its enzymic activity. We found that IDO was involved in intracellular signaling events responsible for the self-amplification and maintenance of a stably regulatory phenotype in pDCs. Thus, IDO has a tonic, nonenzymic function that contributes to TGF-β-driven tolerance in noninflammatory contexts. 相似文献
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Aminah Qayyimah Mohd Aji Dzeti Farhah Mohshim Belladonna Maulianda Khaled Abdalla Elraeis 《RSC advances》2022,12(32):20530
In shale gas reservoirs, adsorbed gas accounts for 85% of the total shale gas in place (GIP). The adsorption isotherms of shale samples are significant for understanding the mechanisms of shale gas storage, primarily for assessing the GIP and developing an accurate gas flow behaviour. Isothermal adsorption experiments primarily determine the adsorption capacity of methane in shale gas reservoirs. However, experimental data is limited due to the heterogeneous properties of shale and extreme reservoir conditions at high pressures and temperatures. This work discusses the effect of total carbon (TOC), pore size distributions, and mineralogical properties on adsorption capacity. In this study, the gravimetric adsorption isotherm measurement method was applied to obtain the adsorption isotherms of methane on four shale core samples from Eagle Ford reservoirs. Four shale core samples with TOC of 9.67% to 14.4% were used. Adsorption experiments were conducted at a temperature of 120 °C and to a maximum pressure of 10 MPa. The data obtained experimentally were compared with adsorption isotherm models to assess each model''s applicability in describing the shale adsorption behaviour. A comparison of these models was performed using fitting and error analysis. It was observed that the calculated absolute adsorption of supercritical methane is higher than the excess adsorption. The percentage of differences between the absolute and excess adsorption is more significant at a pressure higher than the critical methane pressure of 9.6%. Sample EF C has the highest adsorption capacity of 1.308 mg g−1, followed by EF D 1.194 mg g−1, EF B 0.546 mg g−1, and EF A 0.455 mg g−1. Three statistical error analyses, average relative error (ARE), the Pearson chi-square (χ2) test and root mean square error (RMSE) deviation were used to assess the applicability of each model in describing the adsorption behaviour of shale samples. The order of adsorption isotherm fitting with experimental data is Toth > D–R = Freundlich > Langmuir. Error analysis shows that the Toth model has the lowest values compared to other models, 0.6% for EF B, 2.5% for EF C, and 2.2% for EF A and EF D, respectively. Adsorption isotherm can be used to depict the adsorption in shale. 相似文献
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Emmanuel João Nogueira Leal Silva Victor Talarico Leal Vieira Felipe Gonçalves Belladonna Arthur de Siqueira Zuolo Henrique dos Santos Antunes Daniele Moreira Cavalcante Carlos Nelson Elias Gustavo De-Deus 《Journal of endodontics》2018,44(1):168-172
Introduction
The purpose of this study was to evaluate the cyclic and torsional fatigue resistance of the XP-endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) and TRUShape (Dentsply Tulsa Dental Specialties, Tulsa, OK) instruments.Methods
Twenty XP-endo Shaper (30/0.01) instruments and 20 TRUShape (30/0.06v) instruments were used. Cyclic fatigue resistance was tested by measuring the number of cycles and time to fracture in an artificial stainless steel canal with a 60° angle and a 5-mm radius of curvature (n = 10). The torque and angle of rotation at failure of new instruments (n = 10) were measured according to ISO 3630-1. The fracture surface of all fragments was examined with a scanning electron microscope. Results were statistically analyzed using the Student t test at a significance level of P < .05.Results
The XP-endo Shaper instruments showed a significantly longer number of cycles to fracture and time to failure in seconds than the TRUShape instruments (P < .05). The XP-endo Shaper also presented a lower maximum torque load (P < .05) but a significantly higher angular rotation to fracture than TRUShape (P < .05).Conclusions
The XP-endo Shaper instruments showed a higher cyclic fatigue resistance and angle of rotation to fracture but lower torque to failure than TRUShape instruments. 相似文献16.
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Potent antitumor activity of interleukin-27 总被引:11,自引:0,他引:11
Hisada M Kamiya S Fujita K Belladonna ML Aoki T Koyanagi Y Mizuguchi J Yoshimoto T 《Cancer research》2004,64(3):1152-1156
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Recent evidence from different experimental systems has demonstrated that autocrine activation of antigen-presenting cells (APCs) may be important at the initiation of an immune response, and that a specific set of cytokines may meet the dual needs of activating APCs and priming and/or maintaining the antigen-specific T-cell response. Composite factors with p40, including IL-12 (p40/p35) and IL-23 (p40/p19), may be two such immunoregulatory cytokines, their effects encompassing actions on both myeloid APCs and T cells. However, although both cytokines enhance the Th1 costimulatory functions of APCs, and IL-23 does induce IL-12 from APCs, their effects, which in part overlap, can be differentiated from one another. This review summarizes recent data on the actions of IL-12 and IL-23 on dendritic cells and macrophages at the interface between innate and adaptive immunity. 相似文献
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Fallarino F Grohmann U Hwang KW Orabona C Vacca C Bianchi R Belladonna ML Fioretti MC Alegre ML Puccetti P 《Nature immunology》2003,4(12):1206-1212
Regulatory T (T(R)) cells manifest constitutive expression of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), but the function of CTLA-4 in mediating the regulatory function of T(R) cells is unclear. We show here that mouse CD4+CD25+ cells, either resting or induced to overexpress CTLA-4 by treatment with antibody to CD3, initiated tryptophan catabolism in dendritic cells through a CTLA-4-dependent mechanism. This process required B7 expression and cytokine production by the dendritic cells. In contrast, T(R) cells cultured in the presence of bacterial lipopolysaccharide induced tryptophan catabolism by dendritic cells in a CTLA-4-independent but cytokine-dependent way. Thus, regulation of immunosuppressive tryptophan catabolism in dendritic cells might represent a major mechanism of action of T(R) cells. 相似文献