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81.
The glucocorticoid (GC)-induced antiinflammatory molecule annexin I is expressed in leukocytes and has antiinflammatory effects in animal models of arthritis, but the expression of annexin I in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) is unknown. We report the constitutive and dexamethasone (DEX)-inducible expression of annexin I in RA FLS. DEX increased FLS annexin I protein translocation and mRNA expression. Interleukin (IL)-1beta also induced annexin I translocation and mRNA but also increased intracellular protein. DEX and IL-1 had additive effects on annexin I mRNA, but DEX inhibited the inducing effect of IL-1beta on cell surface annexin I. These results indicate that glucocorticoids and IL-1beta upregulate the synthesis and translocation of annexin I in RA FLS, but interdependent signalling pathways are involved.  相似文献   
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Introduction: Alaska Native children have high Helicobacter pylori infection and iron deficiency prevalences, and their average height‐for‐age is lower than US reference populations. During a clinical trial to determine the impact of H. pylori treatment on iron deficiency, we evaluated the effects of H. pylori infection and treatment on growth. Materials and Methods: We measured height and weight for children aged 7–11 years in western Alaska using village‐based measuring devices. H. pylori infection was determined by urea breath test and iron deficiency using serum ferritin. Children with H. pylori infection and iron deficiency entered the treatment phase and received iron alone or iron plus triple therapy for H. pylori. Follow‐up evaluations occurred at 2, 8, and 14 months. We evaluated the association between baseline H. pylori infection and growth; among children in the treatment phase, we also assessed the effect of H. pylori resolution on growth. Results: At baseline, 566 (87.1%) of 650 children were infected with H. pylori. Neither height and weight, nor body mass index differed by H. pylori infection status. Of 189 children in the treatment phase, 20 (10.6%) were uninfected at all three follow‐up periods, and 54 (28.6%) were uninfected for one or two periods. Compared with continuously infected children, children in these two groups had little evidence of improvements in any of the measured growth outcomes. Conclusions: H. pylori infection is not related to growth among Alaska Native children aged 7–11 years. Growth deficiency should not be considered an indication for H. pylori therapy.  相似文献   
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Melastatin-related TRPM ion channels have emerged as novel therapeutic targets due to their potential ability to modulate the function and fate of immune cells during inflammation, innate, and adaptive immunity. Four family members, TRPM1, TRPM2, TRPM4 and TRPM7 have a strong presence in the immune system. TRPM channels regulate ion-homeostasis by sensing cellular redox status and cytoplasmic calcium levels. TRPM2 for example, is highly expressed in phagocytes. This channel is activated by intracellular ADP-ribose upon exposure to oxidative stress and induces cell death. Here we will review the functional links between TRPM-mediated ion conductance, chemotaxis, apoptosis, and innate immunity.  相似文献   
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The frequently occurring alteration of ganglioside expression in tumor cells has been implicated to play a role in the uncontrolled growth of these cells; antibodies to such gangliosides might affect tumor cell growth. We have studied the effect of IgM monoclonal antibodies to two glioma-associated gangliosides, GD3 and GM2, on cell proliferation of four human glioma cell lines and one renal tumor cell line. Of the two anti-ganglioside antibodies tested, only the anti-GD3 antibody resulted in a significant (p<0.005) inhibition of cell proliferation as measured by thymidine incorporation and Brd-U labeling, after 24[emsp4 ]h incubation. The effect was not dependent on any serum factor and no increased cell death was observed. All cell lines contained higher or similar amounts of GM2 than GD3, and both antigens were shown to be expressed on the cell surface and accessible to antibodies. The selective effect of anti-GD3 antibodies as contrasted to the inactivity of anti-GM2 antibodies suggests a possible role for ganglioside GD3 in tumor cell proliferation.  相似文献   
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The human glioma D-54MG cell line grownin vitro primarily expresses ganglio series gangliosides, particularly GM2. Subcutaneous injection of these cells into nude mice produced xenografts with an increased content of the human glioma-associated lacto series gangliosides, primarily 3-isoLM1, an alteration that was dose dependent, with the highest dose (1×108) resulting in a phenotype that was most like that of the inoculum. After one passagein vivo, the lacto series dominated and reached a proportional level that was kept throughout the 10 passages. The mRNA levels of the GM2-synthase clearly coincided with GM2 expression and was 20 times higher in cells grownin vitro than in those grownin vivo. These results support the view that ganglioside expression in human gliomas is strongly influenced by environmental factors. Abbreviations: The gangliosides have been designated according to Svennerholm (Eur J Biochem (1977)79: 11–21) GM3, II3NeuAc-LacCer; GM2, II3NeuAc-GgOse3Cer; GM1, II3NeuAc-GgOse4Cer; GD3, II3(NeuAc)2-LacCer; GD2, II3(NeuAc)2-GgOse3Cer; GD1a, IV3NeuAc, II3NeuAc-GgOse4Cer; GD1b, II3(NeuAc)2-GgOse4Cer; GT1b, IV3NeuAc, II3(NeuAc)2-GgOse4Cer; 3-LM1, IV3NeuAc-nLcOse4Cer; 3-isoLM1, IV3NeuAc-LcOse4Cer; 3,6-isoLD1, IV3NeuAc, III6NeuAc-LcOse4Cer; 38-LM1, IV3(NeuAc)2-nLcOse4Cer. MAb(s), monoclonal antibody (ies); the designation LM1 is used when both 3-isoLM1 and 3-LM1 and LD1, when both 36-isoLD1 and 38-LD1 are included.  相似文献   
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Brown  Sally L.  Henry  Charles L.  Chaney  Rufus  Compton  Harry  DeVolder  Pam S. 《Plant and Soil》2003,249(1):203-215
High metal waste materials from historic mining at the Bunker Hill, Idaho (ID) Superfund site was amended with a range of materials including municipal biosolids, woody debris, wood ash, pulp and paper sludge, and compost. The existing soil or waste material has elevated metal concentrations with total Zn, Pb and Cd ranging from 6000 to 14700, 2100 to 27000 and 9 to 28 mg kg–1, respectively. Surface application of certain amendments including biosolids mixed with wood ash resulted in significant decreases in subsoil acidity as well as subsoil extractable metals. This mixture was sufficient to restore a plant cover to the contaminated areas. At the Bunker Hill site, a surface application of high N biosolids (44 or 66 tons ha–1) in combination with wood ash (220 tons ha–1) with or without log yard debris (20% by volume) or pulp and paper sludge (44 tons ha–1) was able to restore a vegetative cover to the metal contaminated materials for 2 years following amendment application. Plant biomass in 1999 was 0.01 mg ha–1 in the control versus a mean of 3.4 tons ha–1 in the residual amended plots. Metal concentrations of the vegetation indicated that plants were within normal concentrations for the 2 years that data were collected. Surface application of amendments was also able to reduce Ca(NO3)2 extractable Zn in the subsoil from about 50 mg kg–1in the control to less than 4 mg kg–1in two of the treatments. Use of conventional amendments including lime alone and microbial stimulants were not sufficient to support plant growth. These results indicate that surface application of biosolids in combination with other residuals is sufficient to restore a vegetative cover to high metal mine wastes.  相似文献   
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