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991.
Therapeutic Applications of Synthetic CpG Oligodeoxynucleotides as TLR9 Agonists for Immune Modulation 总被引:5,自引:0,他引:5
Jurk M Vollmer J 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》2007,21(6):387-401
Vertebrate toll-like receptors (TLRs) sense invading pathogens by recognizing bacterial and viral structures and, as a result, activate innate and adaptive immune responses. Ten human functional TLRs have been reported so far; three of these (TLR7, 8, and 9) are expressed in intracellular compartments and respond to single-stranded nucleic acids as natural ligands. The pathogen structure selectively recognized by TLR9 in bacterial or viral DNA was identified to be CpG dinucleotides in specific sequence contexts (CpG motifs). Short phosphorothioate-stabilized oligodeoxynucleotides (ODNs) containing such motifs are used as synthetic TLR9 agonists, and different classes of ODN TLR9 agonists have been identified with distinct immune modulatory profiles. The TLR9-mediated activation of the vertebrate immune system suggests using such TLR9 agonists as effective vaccine adjuvants for infectious disease, and for the treatment of cancer and asthma/allergy. Immune activation by CpG ODNs has been demonstrated to be beneficial in animal models as a vaccine adjuvant and for the treatment of a variety of viral, bacterial, and parasitic diseases. Antitumor activity of CpG ODNs has also been established in numerous mouse models. In clinical vaccine trials in healthy human volunteers or in immunocompromised HIV-infected patients, CpG ODNs strongly enhanced vaccination efficiency. Most encouraging results in the treatment of cancers have come from human phase I and II clinical trials using CpG ODNs as a tumor vaccine adjuvant, monotherapy, or in combination with chemotherapy. Therefore, CpG ODNs represent targeted immune modulatory drugs with a broad range of potential applications. 相似文献
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Haagsman A Reuter G Duizer E Nagy G Herremans T Koopmans M Szücs G 《Journal of medical virology》2007,79(7):927-930
Many cases of acute hepatitis remain undiagnosed and the hepatitis E virus (HEV) is emerging in industrialized countries. The aim of this study was to assess the role HEV as causative agent in acute non-A, non-B, and non-C hepatitis patients in Hungary. 10.5% of the 264 acute non-A, non-B, and non-C hepatitis patients tested had anti-HEV IgG and 1.9% had anti-HEV IgM as tested by ELISA. After confirmation by Western blot 6.1% of the acute non-A, non-B, and non-C hepatitis patients had anti-HEV IgG antibodies only and 1.1% of the patients had both IgG and IgM. All 19 patients that were positive for anti-HEV IgG and/or IgM tested negative for HEV RNA by PCR. Only a small proportion of the acute hepatitis cases in the southwest of Hungary are assumed to be attributed to HEV infection, however, hepatitis E should be considered along with hepatitis A, B, and C in the diagnosis of acute hepatitis. 相似文献
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Physico-chemical-mechanical and in vitro biological properties of calcium phosphate cements with doped amorphous calcium phosphates 总被引:1,自引:0,他引:1
Julien M Khairoun I LeGeros RZ Delplace S Pilet P Weiss P Daculsi G Bouler JM Guicheux J 《Biomaterials》2007,28(6):956-965
Calcium phosphate cements (CPCs) are successfully used as bone substitutes in dentistry and orthopaedic applications. This study investigated the physico-chemical-mechanical properties of and in vitro biological properties (cell response) of CPCs prepared with amorphous calcium carbonate phosphate (ACCP) doped with magnesium (ACCP-Mg), zinc (ACCp-Zn) or fluoride (ACCP-F) ions. The experimental CPC consisted of alpha-TCP, doped ACCP, and MPCM powders as matrix and biphasic calcium phosphate (BCP) granules. X-ray diffraction analysis showed that the matrix converted to apatite with poor crystallinity (reflecting small crystal size) after setting for 24 h, while BCP remained apparently unchanged. Cements with ACCP-F (F-CPC) had shorter setting times and greater compressive strength compared to cements with ACCP-Mg (Mg-CPC) or ACCP-Zn (Zn-CPC). Scanning electron microscopy (SEM) showed that crystals set on Mg-CPC and Zn-CPC were smaller compared to those on F-CPC. The total porosity of Mg-CPC was greater compared to Zn-CPC or F-CPC. Osteoblast-like cells, MC3T3-E1, remained viable and maintained their ability to express alkaline phosphatase in contact with the CPCs with doped ACCPs. 相似文献
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Marra CA Marion SA Guh DP Najafzadeh M Wolfe F Esdaile JM Clarke AE Gignac MA Anis AH 《Journal of clinical epidemiology》2007,60(6):616-624
BACKGROUND: There is evidence that utility elicitation methods used in the calculation of quality-adjusted life years (QALYs) yield different results. It is not clear how these differences impact economic evaluations. METHODS: Using a mathematical model incorporating data on efficacy, costs, and utility values, we simulated the experiences of 100,000 hypothetical rheumatoid arthritis patients over 10 years (50,000 exposed to infliximab plus methotrexate [MTX] and 50,000 exposed to MTX alone). QALYs, were derived from the Health Utilities Index 2 and 3 (HUI2 and HUI3), the Short Form 6-D (SF-6D), and the Euroqol 5-D (EQ-5D). Incremental cost-utility ratios were determined using each instrument to calculate QALYs and the results were compared using cost-effectiveness acceptability curves. RESULTS: Using the different utility measurement methods, the mean difference in QALYs between the infliximab plus MTX and MTX groups ranged from a high of 1.95 QALYs (95% CI=1.93-1.97) using the HUI3 to 0.89 QALYs (95% CI=0.88-0.91) using the SF-6D. Adopting the commonly cited value of society's willingness to pay for a QALY of $50,000, 91% of the simulations favored the cost utility of infliximab plus MTX when using the HUI3 to calculate QALYs. However, when using the EQ-5D, HUI2, or the SF-6D utility values to calculate QALYS, the proportion of simulations that favored the cost utility of infliximab were 63%, 45%, and 12%, respectively. CONCLUSION: Depending on the method for determining utility values used in the calculation of QALYs, very different incremental cost-utility ratios are generated. 相似文献
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Despite mandates to provide spiritual care, confusion persists among nurses about spirituality, spiritual needs, and related roles. To discover how practicing nurses acquire knowledge for spiritual care, the authors chose a grounded theory design. They constantly compared and analyzed verbatim transcribed interview data to find the core variable, categories, and properties. Connection, manifesting as a state, act, or process, appeared throughout the data. Categories emerged as Needing Connection, Nurturing Connection, Learning Connection, and Living Connection. Nurses used a cyclical, intertwined, and progressive learning process of opening to, struggling with, and making connections between numerous discrete personal and professional experiences. Shifting attention between these interconnected experiences fueled knowledge acquisition. Whether referring to how nurses learn, what they do, or with whom, the theory Connecting Spiritually joined categories into a cumulative experiential learning process that explained how nurses learn to care for spiritual needs. 相似文献