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IL-8 mRNA in human gingival epithelial cells (HGECs) is up-regulated by Fusobacterium nucleatum, and up-/down-regulated by Porphyromonas gingivalis in a complex interaction in the early stages (< or = 4 h) after infection. The mechanisms involved in this regulation in response to F. nucleatum and/or P. gingivalis infection, and identification of co-regulated cytokine genes, are the focus of this investigation. Heat, formalin or protease treatment of F. nucleatum cells attenuated the IL-8 mRNA up-regulation. NF-kappaB, mitogen-activated protein kinase (MAPK) p38 and MAPK kinase/extracellular signal-regulated kinase (MEK/ERK) pathways were involved in IL-8 mRNA induction by F. nucleatum. Pretreatment of P. gingivalis with heat, formalin or protease enhanced IL-8 mRNA induction. NF-kappaB, MARK p38, and MEK/ERK pathways were also involved in this induction. In contrast, down-regulation of IL-8 mRNA by P. gingivalis involved MEK/ERK, but not NF-kappaB or MAPK p38 pathways. cDNA arrays analysis revealed that mRNA down-regulation by P. gingivalis is a specific reaction that only a number of genes, e.g. IL-1beta, IL-8, macrophage inflammatory protein-2alpha, and migration inhibitory factor-related protein-14, are affected based on examination of 278 cytokine/receptor genes. These data indicate that F. nucleatum and P. gingivalis trigger specific and differential gene regulation pathways in HGECs. 相似文献
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N. T. Kim Oanh B.-E. Bengtsson L. Bætz Reutergårdh D. T. Hoa P.-A. Bergqvist D. Broman Y. Zebühr 《Archives of environmental contamination and toxicology》1999,37(3):303-309
A bleached sulfate integrated pulp and paper mill producing printing and writing paper from mixed tropical hardwood and
bamboo was studied. The mill uses a “conventional bleaching sequence,” C-E-H1-H2, with an average molecular chlorine consumption
of 50 kg per ton of air-dried pulp (ADP). The content of polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs)
in the bleaching filtrate in terms of the nordic toxicity equivalent (N-TEQ) was 33.5, 1.15, 0.56, and 0.014 pg/L for the
E, C, H1, and H2 bleaching stages, respectively. The corresponding PCDFs and PCDDs loads in ng/t ADP were in the same ranking,
i.e., 670, 69, 11.2, and 0.28, respectively. The congener and isomeric pattern of PCDFs and PCDDs of the bleaching filtrate and
the bleached pulp was found to be typical for the chlorine bleaching plant effluent. The obtained dioxin load formed in the
mill is in agreement with Western studies for the given multiple chlorine of 0.21–0.23. The load is, however, lower than reported
discharges from Scandinavian mills using 1980s bleaching technologies, but substantially higher than the discharges from mills
with modern bleaching technologies. Modifications in the bleaching plant to reduce molecular chlorine use are necessary to
reduce dioxin formation.
Received: 15 July 1998/Accepted: 17 March 1999 相似文献
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J Robillard J E Couette J Le Mouel L Van Hoa J C Vernhes R Chédeville 《Journal de radiologie, d'électrologie, et de médecine nucléaire》1976,57(5):429-433
The purpose of the present work is to "quantify" bone scanning, in order to calculate indices of localized uptake that will make it possible to differentiate between normal and pathological uptake, and approach an etiologicial diagnosis. The authors use an Elscint dual head whole body scanner and an offline video display calculator. The patient is given 8 mc technetium 99m pyrophosphate 4 hours prior to scanning. The whole body count is expressed in thousands of counts multipled by two so that the knee to whole body ratio is close to one, to facilitate comparison of the indices. Results show that the presence of metastases is demonstrated more clearly by using a ratio bone segment to whole body. Quantitative scanning with 99mTc-pyrophosphate makes it possible to: 1) detect bone metastases easily, 2) follow the metastases during treatment, 3) avoid the gross errors that can be made in nomquantitative scanning. 相似文献
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Aruna Perera Keith Hyland Hoa K. Nguyen Robert R. Kane 《Journal of labelled compounds & radiopharmaceuticals》2003,46(5):389-394
Concise methods for the synthesis of 4‐hydroxy‐3‐[2H3]‐methoxyphenylalanine (3‐O‐[2H3]‐methydopa) and 3‐hydroxy‐4‐[2H3]‐methoxyphenylalanine (4‐O‐[2H3]‐methydopa) are described. The 3‐O‐[2H3]‐methydopa is a valuable internal standard for the tandem MS quantification of 3‐O‐methyldopa, a metabolite of value in the diagnosis of aromatic l‐amino acid decarboxylase (AADC) deficiency. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Monica Rizzo MD Harvey Bumpers MD Joel Okoli MD Diana Senior-Crosby NP Ruth O’Regan MD Amelia Zelnak MD Lin Pan MS Marina Mosunjac MD Sharla Gayle Patterson MD Sheryl G. A. Gabram MD 《Annals of surgical oncology》2011,18(1):34-39