5 resultados para COX-3

em Deakin Research Online - Australia


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Dietary deficiency of ω3 fatty acid during development leads to impaired cognitive function. However, the effects of multiple generations of ω3 fatty-acid deficiency on cognitive impairment remain unclear. In addition, we sought to test the hypothesis that the cognitive impairments of ω3 fatty-acid-deficient mice are mediated through the arachidonic acid-cyclooxygenase (COX) pathway. To address these issues, C57BL/6J mice were bred for 3 generations and fed diets either deficient (DEF) or sufficient (SUF) in ω3 fatty acids. At postnatal day 21, the F3 offspring remained on the dam's diet or were switched to the opposite diet, creating 4 groups. In addition, 2 groups that remained on the dam's diet were treated with a COX inhibitor. At 19 wk of age, spatial-recognition memory was tested on a Y-maze. Results showed that 16 wk of SUF diet reversed the cognitive impairment of F3 DEF mice. However, 16 wk of ω3 fatty-acid-deficient diet impaired the cognitive performance of the F3 SUF mice, which did not differ from that of the F3 DEF mice. These findings suggest that the cognitive deficits after multigenerational maintenance on ω3 fatty-acid-deficient diet are not any greater than are those after deficiency during a single generation. In addition, treatment with a COX inhibitor prevented spatial-recognition deficits in F3 DEF mice. Therefore, cognitive impairment due to dietary ω3 fatty-acid deficiency appears to be mediated by the arachidonic acid-COX pathway and can be prevented by 16 wk of dietary repletion with ω3 fatty acids or COX inhibition.

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This paper reviews new drug targets in the treatment of depression and new drug candidates to treat depression. Depression is characterized by aberrations in six intertwined pathways: (1) inflammatory pathways as indicated by increased levels of proinflammatory cytokines, e.g. interleukin-1 (IL-1), IL-6, and tumour necrosis factor α. (2) Activation of cell-mediated immune pathways as indicated by an increased production of interferon γ and neopterin. (3) Increased reactive oxygen and nitrogen species and damage by oxidative and nitrosative stress (O&NS), including lipid peroxidation, damage to DNA, proteins and mitochondria. (4) Lowered levels of key antioxidants, such as coenzyme Q10, zinc, vitamin E, glutathione, and glutathione peroxidase. (5) Damage to mitochondria and mitochondrial DNA and reduced activity of respiratory chain enzymes and adenosine triphosphate production. (6) Neuroprogression, which is the progressive process of neurodegeneration, apoptosis, and reduced neurogenesis and neuronal plasticity, phenomena that are probably caused by inflammation and O&NS. Antidepressants tend to normalize the above six pathways. Targeting these pathways has the potential to yield antidepressant effects, e.g. using cytokine antagonists, minocycline, Cox-2 inhibitors, statins, acetylsalicylic acid, ketamine, ω3 poly-unsaturated fatty acids, antioxidants, and neurotrophic factors. These six pathways offer new, pathophysiologically guided drug targets suggesting that novel therapies could be developed that target these six pathways simultaneously. Both nuclear factor (erythroid-derived 2)-like 2 (Nrf2) activators and glycogen synthase kinase-3 (GSK-3) inhibitors target the six above-mentioned pathways. GSK-3 inhibitors have antidepressant effects in animal models of depression. Nrf2 activators and GSK-3 inhibitors have the potential to be advanced to phase-2 clinical trials to examine whether they augment the efficacy of antidepressants or are useful as monotherapy.

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Stability in clinical prediction models is crucial for transferability between studies, yet has received little attention. The problem is paramount in high dimensional data, which invites sparse models with feature selection capability. We introduce an effective method to stabilize sparse Cox model of time-to-events using statistical and semantic structures inherent in Electronic Medical Records (EMR). Model estimation is stabilized using three feature graphs built from (i) Jaccard similarity among features (ii) aggregation of Jaccard similarity graph and a recently introduced semantic EMR graph (iii) Jaccard similarity among features transferred from a related cohort. Our experiments are conducted on two real world hospital datasets: a heart failure cohort and a diabetes cohort. On two stability measures – the Consistency index and signal-to-noise ratio (SNR) – the use of our proposed methods significantly increased feature stability when compared with the baselines.

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Background Androgen-deprivation therapy is offered to men with prostate cancer who have a rising prostate-specific antigen after curative therapy (PSA relapse) or who are considered not suitable for curative treatment; however, the optimal timing for its introduction is uncertain. We aimed to assess whether immediate androgen-deprivation therapy improves overall survival compared with delayed therapy. Methods In this randomised, multicentre, phase 3, non-blinded trial, we recruited men through 29 oncology centres in Australia, New Zealand, and Canada. Men with prostate cancer were eligible if they had a PSA relapse after previous attempted curative therapy (radiotherapy or surgery, with or without postoperative radiotherapy) or if they were not considered suitable for curative treatment (because of age, comorbidity, or locally advanced disease). We used a database-embedded, dynamically balanced, randomisation algorithm, coordinated by the Cancer Council Victoria, to randomly assign participants (1:1) to immediate androgen-deprivation therapy (immediate therapy arm) or to delayed androgen-deprivation therapy (delayed therapy arm) with a recommended interval of at least 2 years unless clinically contraindicated. Randomisation for participants with PSA relapse was stratified by type of previous therapy, relapse-free interval, and PSA doubling time; randomisation for those with non-curative disease was stratified by metastatic status; and randomisation in both groups was stratified by planned treatment schedule (continuous or intermittent) and treatment centre. Clinicians could prescribe any form and schedule of androgen-deprivation therapy and group assignment was not masked. The primary outcome was overall survival in the intention-to-treat population. The trial closed to accrual in 2012 after review by the independent data monitoring committee, but data collection continued for 18 months until Feb 26, 2014. It is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12606000301561) and ClinicalTrials.gov (NCT00110162). Findings Between Sept 3, 2004, and July 13, 2012, we recruited 293 men (261 with PSA relapse and 32 with non-curable disease). We randomly assigned 142 men to the immediate therapy arm and 151 to the delayed therapy arm. Median follow-up was 5 years (IQR 3·3–6·2) from the date of randomisation. 16 (11%) men died in the immediate therapy arm and 30 (20%) died in the delayed therapy arm. 5-year overall survival was 86·4% (95% CI 78·5–91·5) in the delayed therapy arm versus 91·2% (84·2–95·2) in the immediate therapy arm (log-rank p=0·047). After Cox regression, the unadjusted HR for overall survival for immediate versus delayed arm assignment was 0·55 (95% CI 0·30–1·00; p=0·050). 23 patients had grade 3 treatment-related adverse events. 105 (36%) men had adverse events requiring hospital admission; none of these events were attributable to treatment or differed between treatment-timing groups. The most common serious adverse events were cardiovascular, which occurred in nine (6%) patients in the delayed therapy arm and 13 (9%) in the immediate therapy arm. Interpretation Immediate receipt of androgen-deprivation therapy significantly improved overall survival compared with delayed intervention in men with PSA-relapsed or non-curable prostate cancer. The results provide benchmark evidence of survival rates and morbidity to discuss with men when considering their treatment options. Funding Australian National Health and Medical Research Council and Cancer Councils, The Royal Australian and New Zealand College of Radiologists, Mayne Pharma Australia.