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951.
Thompson JA Srivastava MK Bosch JJ Clements VK Ksander BR Ostrand-Rosenberg S 《Cancer immunology, immunotherapy : CII》2008,57(3):389-398
Activation of tumor-reactive T lymphocytes is a promising approach for the prevention and treatment of patients with metastatic
cancers. Strategies that activate CD8+ T cells are particularly promising because of the cytotoxicity and specificity of CD8+ T cells for tumor cells. Optimal CD8+ T cell activity requires the co-activation of CD4+ T cells, which are critical for immune memory and protection against latent metastatic disease. Therefore, we are developing
“MHC II” vaccines that activate tumor-reactive CD4+ T cells. MHC II vaccines are MHC class I+ tumor cells that are transduced with costimulatory molecules and MHC II alleles syngeneic to the prospective recipient. Because
the vaccine cells do not express the MHC II-associated invariant chain (Ii), we hypothesized that they will present endogenously synthesized tumor peptides that are not presented by professional Ii+ antigen presenting cells (APC) and will therefore overcome tolerance to activate CD4+ T cells. We now report that MHC II vaccines prepared from human MCF10 mammary carcinoma cells are more efficient than Ii+ APC for priming and boosting Type 1 CD4+ T cells. MHC II vaccines consistently induce greater expansion of CD4+ T cells which secrete more IFNγ and they activate an overlapping, but distinct repertoire of CD4+ T cells as measured by T cell receptor Vβ usage, compared to Ii+ APC. Therefore, the absence of Ii facilitates a robust CD4+ T cell response that includes the presentation of peptides that are presented by traditional APC, as well as peptides that
are uniquely presented by the Ii− vaccine cells. 相似文献
952.
953.
Martin Underwood Deborah Ashby Pamela Cross Enid Hennessy Louise Letley Jeannett Martin Shahrul Mt-Isa Suzanne Parsons Madge Vickers Ken Whyte 《BMJ (Clinical research ed.)》2008,336(7636):138-142
Objective To determine whether older patients with chronic knee pain should be advised to use topical or oral non-steroidal anti-inflammatory drugs (NSAIDs).Design Randomised controlled trial and patient preference study.Setting 26 general practices.Participants People aged ≥50 with knee pain: 282 in randomised trial and 303 in preference study. Interventions Advice to use topical or oral ibuprofen.Primary outcome measures WOMAC (Western Ontario and McMaster Universities) osteoarthritis index, major and minor adverse effects.Results Changes in global WOMAC scores at 12 months were equivalent. In the randomised trial the difference (topical minus oral) was two points (95% confidence interval −2 to 6); in the preference study, it was one point (−4 to 6). There were no differences in major adverse effects in the trial or study. The only significant differences in secondary outcomes were in the randomised trial. The oral group had more respiratory adverse effects (17% v 7%,95% confidence interval for difference −17% to −2%), the change in serum creatinine was 3.7 mmol/l less favourable (0.9 µmol/l to 6.5 µmol/l); and more participants changed treatments because of adverse effects (16% v 1%, −16% to −5%). In the topical group more participants had chronic pain grade III or IV at three months, and more participants changed treatment because of ineffectiveness.Conclusions Advice to use oral or topical preparations has an equivalent effect on knee pain over one year, and there are more minor side effects with oral NSAIDs. Topical NSAIDs may be a useful alternative to oral NSAIDs.Trial registration ISRCTN 79353052. 相似文献
954.
Macrocyclic hexaoxazoles having one or two lysinyl side chains in which the terminal nitrogen is either a primary amine, N,N-dimethylamine, or an acetamide have been synthesized. Sodium ion has been found to be beneficial to the macrocyclization step by acting as a template around which the linear polyoxazole can organize. Each of the targeted compounds selectivity stabilizes G-quadruplex versus duplex DNA. Compounds with one valine and one lysine residue display the best combination of G-quadruplex stabilizing ability with no detectable stabilization of duplex DNA. 相似文献
955.
Cai ZW Wei D Borzilleri RM Qian L Kamath A Mortillo S Wautlet B Henley BJ Jeyaseelan R Tokarski J Hunt JT Bhide RS Fargnoli J Lombardo LJ 《Bioorganic & medicinal chemistry letters》2008,18(4):1354-1358
Introduction of the 2,4-difluoro-5-(cyclopropylcarbamoyl)phenylamino group at the C-4 position of the pyrrolo[2,1-f][1,2,4] triazine scaffold led to the discovery of a novel sub-series of inhibitors of VEGFR-2 kinase activity. Subsequent SAR studies on the 1,3,5-oxadiazole ring appended to the C-6 position of this new sub-family of pyrrolotriazines resulted in the identification of low nanomolar inhibitors of VEGFR-2. Antitumor efficacy was observed with compound 37 against L2987 human lung carcinoma xenografts in athymic mice. 相似文献
956.
Johnson D. L. J. Hager A. Hunt D. A. Griffith S. Blount S. Ellsworth J. Hintz R. Lucci A. Mittiga D. Prokhorova L. Tidd M. M. Millones M. Vincent 《中国科学C辑(英文版)》2005,48(1):92
A program of house dust sample collection and analysis has begun in Syracuse, New York, USA, in order to determine the feasibility of a geography-based exposure assessment for urban metals. The sampling program, and the protocols it employs, is described for two different types of wipe media, Ghost Wipes and Whatman Filters. Preliminary results show that strong spatial patterns of floor dust loading (mg dust per square foot) can be observed for data aggregated at a spatial scale of about 1600 m (~2.5 km2). Floor dust metal concentrations were similar to those found in other urban environments, with some regional variation. The median floor dust Pb concentration was ~108 mg · kg?1 for this initial data set of ~264 sampled residential locations, and varied from 50 to 1100 mg Pb · kg?1. 相似文献
957.
Gary D. Foster Suzanne Phelan Thomas A. Wadden Debra Gill Jenna Ermold Elizabeth Didie 《Obesity (Silver Spring, Md.)》2004,12(8):1271-1277
Objective: This pilot study assessed the short‐ and long‐term effects of a modified cognitive behavioral treatment designed to facilitate obese patients’ acceptance of a 5% to 10% reduction in initial weight. Research Methods and Procedures: Participants were 17 women with a mean age of 46.5 ± 9.7 years and BMI of 34.7 ± 2.9 kg/m2. They participated in a 40‐week program that included four phases. The first discussed the benefits of modest weight losses and the potential adverse effects of unrealistic expectations. Phase II provided instruction in traditional cognitive behavioral methods of weight control Phase III focused on methods to improve body image and self‐esteem. Phase IV addressed skills for weight maintenance. Changes in weight, self‐esteem, body image, and quality of life were assessed at the end of treatment and 1 year later (week 92). Results: At week 40, participants lost an average of 5.7 ± 5.3% of initial weight, which was associated with significant improvements in body image, self‐esteem, and quality of life. Improvements in psychosocial status were maintained at week 92, although mean weight loss at this time had declined to 2.9 ± 5.6% of initial weight. Increased satisfaction with body weight at week 40 was associated with significantly better maintenance of weight loss at follow‐up (r = ?0.70; p = 0.02). Discussion: Having participants seek only modest initial weight losses does not appear to facilitate weight maintenance. However, increasing patients’ satisfaction with their body weight at the end of treatment may help improve weight maintenance. More research is needed on the relation between satisfaction with initial weight loss and long‐term success. 相似文献
958.
Peng Li Suzanne Oparil Wenguang Feng Yiu-Fai Chen 《Journal of applied physiology》2004,97(4):1550-8; discussion 1549
This study tested the hypothesis that expression of the novel adhesion molecule periostin (PN) and osteopontin (OPN) is increased in lung and in isolated pulmonary arterial smooth muscle cells (PASMCs) in response to the stress of hypoxia and explored the signaling pathways involved. Adult male rats were exposed to 10% O2 for 2 wk, and growth-arrested rat PASMCs were incubated under 1% O2 for 24 h. Hypoxia increased PN and OPN mRNA expression in rat lung. In PASMCs, hypoxia increased PN but not OPN expression. The hypoxia-responsive growth factors fibroblast growth factor-1 (FGF-1) and angiotensin II (ANG II) caused dose- and time-dependent increases in PN and OPN expression in PASMCs. FGF-1-induced PN expression was blocked by the FGF-1 receptor antagonist PD-166866 and by inhibitors of phosphatidylinositol 3-kinase (PI3K) (LY-294002, wortmannin), p70S6K (rapamycin), MEK1/2 (U-0126, PD-98059), and p38MAPK (SB-203580) but not of JNK (SP-600125). ANG II-induced PN expression was blocked by the AT(1)-receptor antagonist losartan and by inhibitors of PI3K and MEK1/2. In contrast, FGF-1-induced OPN expression was blocked by inhibitors of JNK or MEK1/2 but not of PI3K, p70S6K, or p38MAPK. Activation of p70S6K and p38MAPK by anisomycin robustly stimulated PN but not OPN expression. This study is the first to demonstrate that growth factor-induced expression of PN in PASMCs is mediated through PI3K/p70S6K, Ras/MEK1/2, and Ras/p38MAPK signaling pathways, whereas the expression of OPN is mediated through Ras/MEK1/2 and Ras/JNK signaling pathways. These differences in signaling suggest that PN and OPN may play different roles in pulmonary vascular remodeling under pathophysiological conditions. 相似文献
959.
Vince P. Palace Christopher Baron Robert E. Evans Jodi Holm Suzanne Kollar Kerry Wautier Jeffrey Werner Paula Siwik George Sterling Craig F. Johnson 《Environmental Biology of Fishes》2004,70(2):169-174
Selenium (Se) is an essential nutrient, but in higher concentrations can reduce recruitment in fish populations by increasing
rates of deformities during early development. Recent work has identified elevated levels of Se in water and biota collected
downstream from coal mining activity in Alberta's northeast slopes region. We also recently identified increased incidence
of terata and edema in rainbow trout and brook trout with elevated tissue Se from this area. However, there is currently no
information regarding the potential for Se to contribute to declining stocks of bull trout, a species of concern in the area.
The present study provides an assessment of the potential for Se to contribute to low recruitment in bull trout downstream
from coal mining activity. Non-destructive muscle biopsy sampling and a sensitive atomic fluorescence analysis technique are
used to determine Se. Results indicate that most bull trout (>90%) captured immediately downstream from coal mining activity
in the region have concentrations of Se that would be expected to impair recruitment. Additional work is required to determine
the extent of Se's contribution to low recruitment in bull trout. 相似文献
960.