Objective: This interlaboratory round robin test investigated the robustness of the Chevron-Notch Beam (CNB) test method and the effect of the processing and testing variations on the fracture toughness of a dental 3Y-TZP ceramic.
Methods: The round robin test was performed precisely following the procedures recommended in ISO 24370:2005 and applied on a commercial 3Y-TZP ceramic (product information). A total of 335 test specimens with dimensions 3×4 x 45 mm³ was equally distributed among 10 participating laboratories of varying experience in fracture toughness testing.
Energy dissipation due to friction and wear is reducing the energy efficiency and reliability of mechanical systems. Thus, great efforts are being made to minimize friction for technical applications. In our present work, we investigate the tribological behavior of stainless steel 100Cr6 with a-C:H and a-C:H:Si coating lubricated with a surface-active formanisotropic 1,3-diketone.
View Article and Find Full Text PDFCD4(+)CD25(high)Foxp3(+) regulatory T cells (Tregs) can suppress other immune cells and, thus, are critical mediators of peripheral self-tolerance. On the one hand, Tregs avert autoimmune disease and allergies. On the other hand, Tregs can prevent immune reactions against tumors and pathogens.
View Article and Find Full Text PDFCD4(+)CD25(++)Foxp3(+) regulatory T cells (Tregs) control self-reactive cells to maintain peripheral tolerance. Treg homeostasis has to be controlled tightly to ensure balanced Treg-mediated suppression. One mechanism that regulates the CD4(+) T cell pool is activation-induced cell death (AICD).
View Article and Find Full Text PDFObjective: To determine the frequency and suppressive capacity of regulatory T cells (T(reg)) and their association with clinical parameters in patients with systemic scleroderma (SSc).
Methods: Peripheral blood from 25 patients with SSc, 15 patients with localised scleroderma (LS) and 29 healthy controls (HC) was studied. Analysis of CD4(+) forkhead box P3 (Foxp3)(+) and CD4(+)CD25(++)Foxp3(+) T(reg) subpopulations was carried out by flow cytometry and cell proliferation was quantified by (3)H-thymidine incorporation.
J Invest Dermatol
December 2009
Cutaneous T-cell lymphoma (CTCL) has been suggested by in vitro experiments to represent a malignant CD4+ T-cell proliferation with a regulatory T-cell (Treg) phenotype (CD4+CD25+FOXP3+). We investigated percentages of FOXP3+ and CD25+ cells in the blood of 15 Sézary, 14 mycosis fungoides (MF), and 10 psoriasis (Pso) patients and 20 normal healthy donors (NHDs). We found similar numbers of FOXP3+ cells in MF (10.
View Article and Find Full Text PDFCD4+CD25(high) forkhead box P3+ regulatory T cells (Treg) are critical mediators of peripheral self-tolerance and immune homeostasis. Treg suppress proliferation and cytokine production of conventional T cells (Tcon). The exact mechanism of suppression, however, is still unknown.
View Article and Find Full Text PDFAnalgesics given preoperatively have the potential to decrease the amount of inhalant anesthetics required intraoperatively (i.e., to decrease the minimum alveolar concentration, or MAC, for the inhalant).
View Article and Find Full Text PDFObjective: To define the phenotype and function of CD4+,CD25+ regulatory T cells (Treg) in patients with cutaneous lupus erythematosus (CLE), a heterogeneous autoimmune disease characterized primarily by inflammatory skin lesions.
Methods: The number of Treg in skin specimens obtained from patients with various subtypes of CLE was investigated by immunohistochemical analysis, using anti-Foxp3 and anti-CD4 monoclonal antibodies. Furthermore, characterization of peripheral blood CD4+,CD25+ Treg from normal healthy donors and patients with CLE was carried out by flow cytometry, analyzing the expression of Foxp3 and Treg subpopulations.
Most CD4(+)CD25(hi)FOXP3(+) regulatory T cells (T(regs)) from adult peripheral blood express high levels of CD45RO and CD95 and are prone to CD95L-mediated apoptosis in contrast to conventional T cells (T(convs)). However, a T(reg) subpopulation remained consistently apoptosis resistant. Gene microarray and 6-color flow cytometry analysis including FOXP3 revealed an increase in naive T-cell markers on the CD95L-resistant T(regs) compared with most T(regs).
View Article and Find Full Text PDFCutaneous T-cell lymphomas (CTCL) are mainly comprised of two variants: mycosis fungoides (MF) with CD4(+) tumor cells confined to the skin and the leukemic Sézary syndrome with tumor cell spread to the blood. In this study, we investigated cutaneous expression of the regulatory T-cell (T(reg)) marker FOXP3 in 30 CTCL patients. Immunohistochemical analysis revealed significantly lower numbers of CD4(+)FOXP3(+) cells within the dermal lymphomononuclear infiltrate of Sézary patients (16% FOXP3(+) cells of CD4(+) cells) in contrast to MF (43% FOXP3(+) cells (P<0.
View Article and Find Full Text PDFCD4(+)CD25(+)FoxP3(+) regulatory T cells (T(reg)) suppress T cell function and protect rodents from autoimmune disease. Regulation of T(reg) during an immune response is of major importance. Enhanced survival of T(reg) is beneficial in autoimmune disease, whereas increased depletion by apoptosis is advantageous in cancer.
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