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101.
BACKGROUND: The cardiovascular (CV) safety of non-steroidal anti-inflammatory drugs (NSAIDs) and selective cyclooxygenase-2 inhibitors has been the subject of considerable debate. OBJECTIVE: The objective of this study was to determine the risk of CV events with lumiracoxib by meta-analysis of all completed, randomized controlled trials (RCTs) of > or =1 week and up to 1 year in duration of patients with osteoarthritis and rheumatoid arthritis. METHODS: The Novartis Lumiracoxib Clinical Trial Database, which includes all clinical studies conducted to date with lumiracoxib, was reviewed. Data were extracted from RCTs of > or =1 week and up to 1 year in duration, the maximum study duration; 34,668 patients were included in standard and cumulative meta-analyses. Twenty-two RCTs of lumiracoxib 100 to 1200 mg daily were identified; 22,781 patients were included in 1-year trials. Mean age of the patients was 61.5 years and 74% were female. More than 50% of the patients in these studies had hypertension at baseline and 6% had diabetes. Parameters analyzed were the Antiplatelet Trialists' Collaboration (APTC) composite CV end point of myocardial infarction (MI), stroke (ischemic and hemorrhagic), and CV death; MI alone; and stroke alone. Twenty-one of the 22 RCTs have been published. RESULTS: For all 3 parameters, relative risk (RR) was calculated versus non-naproxen NSAIDs, naproxen, and placebo. The results were as follows: for the APTC end point versus non-naproxen NSAIDs: RR 0.83, 95% CI, 0.46-1.51; versus naproxen: RR 1.49, 95% CI, 0.94-2.36; versus placebo: RR 1.08, 95% CI, 0.41-2.86; for MI alone versus non-naproxen NSAIDs: RR 0.80, 95% CI, 0.28-2.25; versus naproxen: RR 1.69, 95% CI, 0.82-3.48; versus placebo: RR 1.27, 95% CI, 0.25-6.56; and for stroke alone versus non-naproxen NSAIDs: RR 0.91, 95% CI, 0.35-2.35; versus naproxen: RR 1.42, 95% CI, 0.70-2.91; versus placebo: RR 0.59, 95% CI, 0.13-2.74. Cumulative meta-analyses of lumiracoxib versus all comparators (placebo, diclofenac, ibuprofen, celecoxib, rofecoxib, and naproxen) did not find any significant differences in APTC, MI alone, or stroke alone. CONCLUSION: This meta-analysis of 34,668 patients receiving > or =1 week and up to 1 year of treatment found no evidence that lumiracoxib was associated with a significant increase in CV risk compared with naproxen, placebo, or all comparators (placebo, diclofenac, ibuprofen, celecoxib, rofecoxib, and naproxen).  相似文献   
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Background

Counseling in combination with pedometer use has proven to be effective in increasing physical activity and improving health outcomes. We investigated the cost-effectiveness of this intervention targeted at one million insufficiently active adults who visit their general practitioner in the Netherlands.

Methods

We used the RIVM chronic disease model to estimate the long-term effects of increased physical activity on the future health care costs and quality adjusted life years (QALY) gained, from a health care perspective.

Results

The intervention resulted in almost 6000 people shifting to more favorable physical-activity levels, and in 5100 life years and 6100 QALYs gained, at an additional total cost of EUR 67.6 million. The incremental cost-effectiveness ratio (ICER) was EUR 13,200 per life year gained and EUR 11,100 per QALY gained. The intervention has a probability of 0.66 to be cost-effective if a QALY gained is valued at the Dutch informal threshold for cost-effectiveness of preventive intervention of EUR 20,000. A sensitivity analysis showed substantial uncertainty of ICER values.

Conclusion

Counseling in combination with pedometer use aiming to increase physical activity may be a cost-effective intervention. However, the intervention only yields relatively small health benefits in the Netherlands.  相似文献   
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Peroxidase-H2O2-halide system: Cytotoxic effect on mammalian tumor cells   总被引:28,自引:0,他引:28  
Clark  RA; Klebanoff  SJ; Einstein  AB; Fefer  A 《Blood》1975,45(2):161-170
Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo.  相似文献   
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Because there is no consensus regarding the precise distribution of induced endothelial tissue factor (TF), we studied TF activity in and on tumor necrosis factor alpha-stimulated cultured human umbilical vein endothelial cells (ECs) and their underlying matrix. TF was mainly expressed on the cell surface. Only small traces were found on the apical surface suggesting that TF is predominantly located on the basolateral side of the cell membrane. The presence of TF on the cell surface was confirmed by flow cytometry. Subendothelial TF activity appeared to be dependent upon the procedure used to remove the stimulated EC monolayer. Whereas ammonium hydroxide or hypotonic lysis resulted in relatively high levels of matrix-associated TF, virtually no TF was found on the matrix after mild enzymatic detachment of stimulated ECs. Cell removal with EDTA resulted in intermediate levels of matrix-associated TF. Neither the enzymatic treatment nor EDTA degraded or removed this TF activity. Similar patterns were observed for matrix-associated TF antigen and EC surface markers. Electron microscopic analysis showed cell fragments on the matrix after monolayer lysis. The findings strongly suggest that induced endothelial TF associated with the subendothelial matrix actually represents TF on EC remnants.  相似文献   
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Ohne ZusammenfassungMit 3 Abbildungen auf Tafel 1 und 19 Abbildungen im Text.  相似文献   
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