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31.
Interleukin 10 (IL-10) has recently been shown to induce normal human B lymphocytes to proliferate and differentiate into immunoglobulin (Ig)-secreting cells. Herein, we show that IL-10 also promotes DNA synthesis and IgM production by anti-CD40 activated B cell chronic lymphocytic leukemia (B-CLL). Most strikingly, IL-2 and IL-10 were found to synergize to induce the proliferation and differentiation of B-CLL cells. This synergy between IL-2 and IL-10 was also observed with normal B cells which proliferated strongly and secreted large amounts of IgM, IgG, and IgA. The observed synergy is likely to be due to the IL-10-induced increase of high affinity IL-2 receptors on both normal and leukemic B cells. This increase of high affinity receptor is associated to an increase of Tac/CD25 expression that can be detected by flow cytometric analysis. Taken together, these results indicate that IL-10 permits anti-CD40 activated B cells to respond to IL-2 through an induction of high affinity IL-2 receptors. This effect of IL-10 may partly explain how T cells, which activate B cells in a CD40-dependent fashion, induce B cell proliferation and differentiation mostly through IL-2.  相似文献   
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The association of congenital heart block (CHB) with maternal autoantibodies to the Ro and La ribonucleoprotein antigens may be due to cross-reactions between maternal anti-La antibodies and fetal cardiac specific antigens. One of the major components of cardiac myocytes, laminin, is accessible for binding by maternal autoantibodies and we have previously reported cross-reactivity of mouse laminin with anti-La antibodies affinity purified from the sera of patients with primary Sj?gren's syndrome. Affinity purified anti-La antibodies from ten women who had at some time given birth to a child with CHB were examined for cross-reactivity with human placental laminin, which shares structural similarities with cardiac laminin. All ten anti-La antibodies bound to the surface of cryosections of normal full term placental trophoblasts. Binding could be inhibited by pre-incubation of antibodies with either La or placental laminin. Eight anti-La antibodies also reacted with placental laminin by ELISA and La inhibited up to 82% of binding to laminin while laminin inhibited up to 85% of binding to La in a dose dependent manner. Eight anti-La antibodies also bound to the surface of fetal cardiac myocytes at 10.3 weeks of gestation and five showed lower levels of reactivity with the surface of fetal cardiac myocytes at 16.5 weeks of gestation. None showed any surface staining of normal adult heart. These data confirm the cross-reactivity of anti-La antibodies with laminin and may support a placental role in preventing the majority of potentially pathogenic antibodies from reaching the fetal circulation.  相似文献   
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High density peptide and oligonucleotide chips are fabricated using semiconductor-based technologies. These chips have a variety of biological applications.  相似文献   
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Although the influence of the menstrual cycle on both vaginal candidosis and Candida albicans adherence to vaginal epithelial cells in vitro has been shown to be significant, similar studies have not been made on oral candidosis and adherence to buccal epithelial cells. The aim of this study was therefore to use an in vitro adherence assay to investigate the possible influence of the menstrual cycle on the adherence of C. albicans to buccal epithelial cells. Epithelial cells were collected from a single, healthy, female volunteer on days 5, 15, 22 and 28 of six menstrual cycles. Adherence of C. albicans was significantly higher to buccal epithelial cells collected on day 5 of the menstrual cycle when compared with days 15, 22 and 28, both in terms of the percentage of buccal epithelial cells with adherent C. albicans and the number of C. albicans adhering per 200 buccal epithelial cells in four out of six menstrual cycles (p < 0.001). This result indicates that hormonal influences should be considered when buccal epithelial cells are used in vitro to assess candidal adherence and may implicate hormonal factors in the aetiology of oral candidosis.  相似文献   
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The eight portland cements and two calcium aluminate cements in the Standard Reference Material (SRM) 1880 series are among the most popular SRMs in the catalog of the National Institute of Standards and Technology (NIST) Standard Reference Materials Program. Numerous laboratories rely on them for elemental analysis and qualification for ASTM C 114-00 Standard Test Methods for Chemical Analysis of Hydraulic Cement. NIST has collected new candidate materials from around the world and partnered with Construction Technology Laboratories (CTL) in their preparation and certification. This paper describes the procedures taken at NIST and CTL to prepare and test materials for certification including the homogeneity testing, the X-ray fluorescence methods and the statistical data analysis performed for value assignment.  相似文献   
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Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively.  相似文献   
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