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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Genoprotective effect of aspirin and ibuprofen in human lymphocyte cells. Effect of nano and bulk forms of aspirin and ibuprofen on lymphocytes from breast cancer patients compared with those from healthy females

Dandah, Osama M.M. January 2017 (has links)
ABSTRACT: Various recent studies have suggested that regular intake of some non-steroidal anti-inflammatory drugs (NSAIDs) have a preventative effect against several types of tumours including breast cancer. The term nanotechnology refers to technology in which one-billionth of a meter is used as a scale for chemical particle size. This work aims to study the effect of both ibuprofen and aspirin on DNA damage using peripheral blood lymphocytes from breast cancer patients and comparing the results with those from healthy females as a control using the Comet and micronucleus assays. Western blot analysis (WBA) was used to investigate the effect of these drugs on XRCC3 and p53 proteins, whereas QPCR was to evaluate this effect on p53, cox1 and cox2 genes. Two hundred fifty ng/ml of ibuprofen (NP and bulk) and 500 ng/ml of aspirin (NP and bulk) were used to treat the lymphocytes. Both aspirin and ibuprofen caused a reduction in DNA damage and micronucleus formation. Aspirin, both forms, showed a reduction in DNA damage in the Comet and micronucleus assays. Ibuprofen both forms, by contrast, showed a statistically significant reduction in micronucleus frequency in the micronucleus assay, while its preventative effect with the Comet assay was weak or insignificant. NPs of both agents were more effective than bulk sizes. Using the Comet repair assay, aspirin and ibuprofen nano form catalysed DNA repair to a greater extent than their bulk forms. Also, both sizes showed better repair with NSAIDs compared to samples repaired without NSAIDs. In WBA aspirin increased the expression of XRCC3 protein in healthy cells. However, both NSAIDs decreased that expression in cells from BC patients. Furthermore, aspirin increased p53 expression in BC patients lymphocytes. With the QPCR method, results of both aspirin forms increased the expression of the p53 gene in BC patient cells statistically significantly. Both drugs reduced cox1 expression in healthy volunteers and cancer patients lymphocytes. Moreover, cox2 reduction was only in lymphocytes from BC patients. The results of this work are consistent with the view that NSAIDs, particularly aspirin and ibuprofen, could have a promising role in cancer treatment including breast cancer. / Various recent studies have suggested that regular intake of some non-steroidal anti-inflammatory drugs (NSAIDs) have a preventative effect against several types of tumours including breast cancer. The term nanotechnology refers to technology in which one-billionth of a meter is used as a scale for chemical particle size. This work aims to study the effect of both ibuprofen and aspirin on DNA damage using peripheral blood lymphocytes from breast cancer patients and comparing the results with those from healthy females as a control using the Comet and micronucleus assays. Western blot analysis (WBA) was used to investigate the effect of these drugs on XRCC3 and p53 proteins, whereas QPCR was to evaluate this effect on p53, cox1 and cox2 genes. Two hundred fifty ng/ml of ibuprofen (NP and bulk) and 500 ng/ml of aspirin (NP and bulk) were used to treat the lymphocytes. Both aspirin and ibuprofen caused a reduction in DNA damage and micronucleus formation. Aspirin, both forms, showed a reduction in DNA damage in the Comet and micronucleus assays. Ibuprofen both forms, by contrast, showed a statistically significant reduction in micronucleus frequency in the micronucleus assay, while its preventative effect with the Comet assay was weak or insignificant. NPs of both agents were more effective than bulk sizes. Using the Comet repair assay, aspirin and ibuprofen nano form catalysed DNA repair to a greater extent than their bulk forms. Also, both sizes showed better repair with NSAIDs compared to samples repaired without NSAIDs. In WBA aspirin increased the expression of XRCC3 protein in healthy cells. However, both NSAIDs decreased that expression in cells from BC patients. Furthermore, aspirin increased p53 expression in BC patients lymphocytes. With the QPCR method, results of both aspirin forms increased the expression of the p53 gene in BC patient cells statistically significantly. Both drugs reduced cox1 expression in healthy volunteers and cancer patients lymphocytes. Moreover, cox2 reduction was only in lymphocytes from BC patients. The results of this work are consistent with the view that NSAIDs, particularly aspirin and ibuprofen, could have a promising role in cancer treatment including breast cancer. / Libyan Government
102

A Preliminary Study of the Interaction of Acidic and Basic Drugs Using Ethyl Cellulose Microspheres

Walker, Heather M. January 2012 (has links)
No description available.
103

Protective effects of Zinc-L-Carnosine/ Vitamin E on aspirin-induced gastroduodenal injury in dogs

Baan, Mieke 15 July 2009 (has links)
No description available.
104

A Systematic Review and Meta-Analysis of Studies of Preoperative Aspirin on Bleeding and Cardiovascular Outcomes of Patients Undergoing Coronary Artery Bypass Surgery: A Comparison of Bayesian and Classical Approaches

Cheng, Ji 04 1900 (has links)
<p> Meta-analysis is a statistical method to summarize the overall evidence of effects on intervention by systematically combining outcomes from available studies in the literature which are homogeneous in research methodology and research interest. The objective of this project is to evaluate the treatment effects of preoperative aspirin on bleeding and other cardiovascular outcomes from 11 randomized control trials (RCT) and 19 observational (non-RCT) studies. Both Bayesian meta-analysis and classical (frequentist) meta-analysis were applied to continuous and binary outcomes, and the results were compared.</p> <p> The robustness of the Bayesian approach is assessed by examining the performances of different likelihood functions and priors. We also discuss strategies on dealing with zero-event studies for binary outcomes, and the implementation of multiple imputation (MI) technique to missing data for continuous outcomes.</p> <p> Most results of primary analysis agree between the Bayesian and classical approaches. We suggest that the final conclusion of a meta-analysis should be based on the comparison of the results from both Bayesian and classical approaches.</p> / Thesis / Master of Science (MSc)
105

DNA Damage in Healthy Individuals and Respiratory Patients after Treating Whole Blood In vitro with the Bulk and Nano Forms of NSAIDs

Najafzadeh, Mojgan, Normington, Charmaine, Jacob, B.K., Isreb, Mohammad, Gopalan, Rajendran C., Anderson, Diana 2016 August 1923 (has links)
Yes / Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit COX enzyme activity which affects the inflammatory response. Inflammation is associated with increasing cancer incidence. Pre-clinical and clinical studies have shown that NSAID treatment could cause an anti-tumor effect in cancers. In the present study, blood was taken from healthy individuals (n = 17) and patients with respiratory diseases or lung cancer (n = 36). White blood cells (WBC) were treated with either a micro-suspension, i.e., bulk (B) or nano-suspension (N) of aspirin (ASP) or ibuprofen (IBU) up to 500 μg/ml in the comet assay and up to 125 μg/ml in the micronucleus assay. In this study results were compared against untreated lymphocytes and their corresponding treated groups. The results showed, that NSAIDs in their nano form significantly reduced the DNA damage in WBCs from lung cancer patients in bulk and nano compared to untreated lymphocytes. Also, there was a decrease in the level of DNA damage in the comet assay after treating WBCs from healthy individuals, asthma and COPD groups with aspirin N (ASP N) but not with IBU N. In addition, the number of micronuclei decreased after treatment with NSAIDs in their nano form (ASP N and IBU N) in the healthy as well as in the lung cancer group. However, this was not the case for micronucleus frequency in asthma and COPD patients. These data show that lymphocytes from different groups respond differently to treatment with ASP and IBU as measured by comet assay and micronucleus assay, and that the size of the suspended particles of the drugs affects responses. / The present study was part funded by United Kingdom India Education Research Initiative (UKERI) SA 07-067.
106

A randomised controlled trial of eicosapentaenoic acid and/or aspirin for colorectal adenoma (or polyp) prevention during colonoscopic surveillance in the NHS Bowel Cancer Screening Programme: The seAFOod (Systematic Evaluation of Aspirin and Fish Oil) Polyp Prevention Trial

Hull, M.A., Sandell, A.C., Montgomery, A.A., Logan, R.F.A., Clifford, G.M., Rees, C.J., Loadman, Paul, Whitham, D. 07 2013 (has links)
Yes / The naturally-occurring omega (ω)-3 polyunsaturated fatty acid (PUFA) eicosapentaenoic acid (EPA) reduces colorectal adenoma (polyp) number and size in patients with familial adenomatous polyposis. The safety profile and potential cardiovascular benefits associated with ω-3 PUFAs make EPA a strong candidate for colorectal cancer (CRC) chemoprevention, alone or in combination with aspirin, which itself has recognized anti-CRC activity. Colorectal adenoma number and size are recognized as biomarkers of future CRC risk and are established as surrogate end-points in CRC chemoprevention trials. The seAFOod Polyp Prevention Trial is a randomized, double-blind, placebo-controlled, 2 × 2 factorial ‘efficacy’ study, which will determine whether EPA prevents colorectal adenomas, either alone or in combination with aspirin. Participants are 55–73 year-old patients, who have been identified as ‘high risk’ (detection of ≥5 small adenomas or ≥3 adenomas with at least one being ≥10 mm in diameter) at screening colonoscopy in the English Bowel Cancer Screening Programme (BCSP). Exclusion criteria include the need for more than one repeat endoscopy within the three-month BCSP screening period, malignant change in an adenoma, regular use of aspirin or non-aspirin non-steroidal anti-inflammatory drugs, regular use of fish oil supplements and concomitant warfarin or anti-platelet agent therapy. Patients are randomized to either EPA-free fatty acid 1 g twice daily or identical placebo AND aspirin 300 mg once daily or identical placebo, for approximately 12 months. The primary end-point is the number of participants with one or more adenomas detected at routine one-year BCSP surveillance colonoscopy. Secondary end-points include the number of adenomas (total and ‘advanced’) per patient, the location (left versus right colon) of colorectal adenomas and the number of participants re-classified as ‘intermediate risk’ for future surveillance. Exploratory end-points include levels of bioactive lipid mediators such as ω-3 PUFAs, resolvin E1 and PGE-M in plasma, urine, erythrocytes and rectal mucosa in order to gain insights into the mechanism(s) of action of EPA and aspirin, alone and in combination, as well as to discover predictive biomarkers of chemopreventive efficacy. The recruitment target is 904 patients. / Medical Research Council (MRC) and managed by the National Institute for Health Research (NIHR) on behalf of the MRC-NIHR partnership
107

Anticancer roles of platelets and aspirin tested on A549 cells

Shang, Lijun, Zhang, Z., Chen, F. 08 1900 (has links)
No / Aspirin, formally known as acetylsalicylic (ASA), is most widely used and cheapest over-the counter drugs. It is used not only for the common fevers, headaches and inflammation, but also for reducing the risk of heart attacks. In recent years, it is also linked to anti-cancer potential. Recently the US Preventive Services Working Group (UPSTF) release aspirin as a guide for cardiovascular disease and primary prevention of colorectal cancer. Platelets have been shown to play a crucial role in cancer metastasis for many years and are proposed to have an intimate reciprocal crosstalk with cancer cells. They may alter the properties of each other and have reciprocal effects. But the exact role of platelets in modifying the tumor cell properties has not been established. In clinical, cancer patients may receive platelets from outside to treat thrombocytopenia and bleeding induced by intensive chemotherapy. Therefore understanding the exact role of platelets in carcinogenesis always is a research interest, especially when evaluating anti-cancer drugs. In this study we exam the effect of platelets on viability, proliferation and adhesion of lung cancer cells A549 in culture conditions, using different concentrations of platelet rich plasma (PRP) with and without the presence of antiplatelet drug aspirin. The tumor cell EMT transformation was also investigated under different combination of PRP and aspirin in vitro. Our data showed that low-dose of aspirin can promote cell proliferation and high-dose of aspirin could inhibit cell proliferation. High concentrations of platelet-rich plasma can inhibit cell proliferation but low concentrations of platelet-rich plasma had no significant effect on cell proliferation. Platelet-rich plasma can gather around the cell to form a gelatinous film, and this lead us to a promoted tumor cell distant metastasis model. We further found out that the combination of aspirin and PRP could increase cell viability compared to single use of PRP and Aspirin can affect cell proliferation by inhibiting platelet effects. Platelet-rich plasma reduces the adhesion of A549 cell can be attenuated by aspirin. Further works will focus on combination of different doses of aspirin and PRP to confirm the above results. Other format of aspirin (nano-form) and other NSAID inflammatory drugs like Ibuprofen will also be tested. / Abstract of conference paper.
108

Eicosapentaenoic acid and aspirin, alone and in combination, for the prevention of colorectal adenomas (seAFOod Polyp Prevention trial): a multicentre, randomised, double-blind, placebo-controlled, 2 × 2 factorial trial

Hull, M.A., Sprange, K., Hepburn, T., Tan, W., Shafayat, A., Rees, C.J., Clifford, G., Logan, R.F., Loadman, Paul, Williams, E.A., Whitham, D., Montgomery, A.A. 19 November 2018 (has links)
Yes / Background: The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) and aspirin both have proof of concept for colorectal cancer chemoprevention, aligned with an excellent safety profile. Therefore, we aimed to test the efficacy of EPA and aspirin, alone and in combination and compared with a placebo, in individuals with sporadic colorectal neoplasia detected at colonoscopy. Methods: In a multicentre, randomised, double-blind, placebo-controlled, 2 × 2 factorial trial, patients aged 55–73 years who were identified during colonoscopy as being at high risk in the English Bowel Cancer Screening Programme (BCSP; ≥3 adenomas if at least one was ≥10 mm in diameter or ≥5 adenomas if these were <10 mm in diameter) were recruited from 53 BCSP endoscopy units in England, UK. Patients were randomly allocated (1:1:1:1) using a secure web-based server to receive 2 g EPA-free fatty acid (FFA) per day (either as the FFA or triglyceride), 300 mg aspirin per day, both treatments in combination, or placebo for 12 months using random permuted blocks of randomly varying size, and stratified by BCSP site. Research staff and participants were masked to group assignment. The primary endpoint was the adenoma detection rate (ADR; the proportion of participants with any adenoma) at 1 year surveillance colonoscopy analysed in all participants with observable follow-up data using a so-called at-the-margins approach, adjusted for BCSP site and repeat endoscopy at baseline. The safety population included all participants who received at least one dose of study drug. The trial is registered with the International Standard Randomised Controlled Trials Number registry, number ISRCTN05926847. Findings: Between Nov 11, 2011, and June 10, 2016, 709 participants were randomly assigned to four treatment groups (176 to placebo, 179 to EPA, 177 to aspirin, and 177 to EPA plus aspirin). Adenoma outcome data were available for 163 (93%) patients in the placebo group, 153 (85%) in the EPA group, 163 (92%) in the aspirin group, and 161 (91%) in the EPA plus aspirin group. The ADR was 61% (100 of 163) in the placebo group, 63% (97 of 153) in the EPA group, 61% (100 of 163) in the aspirin group, and 61% (98 of 161) in the EPA plus aspirin group, with no evidence of any effect for EPA (risk ratio [RR] 0·98, 95% CI 0·87 to 1·12; risk difference –0·9%, –8·8 to 6·9; p=0·81) or aspirin (RR 0·99 (0·87 to 1·12; risk difference –0·6%, –8·5 to 7·2; p=0·88). EPA and aspirin were well tolerated (78 [44%] of 176 had ≥1 adverse event in the placebo group compared with 82 [46%] in the EPA group, 68 [39%] in the aspirin group, and 76 [45%] in the EPA plus aspirin group), although the number of gastrointestinal adverse events was increased in the EPA alone group at 146 events (compared with 85 in the placebo group, 86 in the aspirin group, and 68 in the aspirin plus placebo group). Six upper-gastrointestinal bleeding events were reported across the treatment groups (two in the EPA group, three in the aspirin group, and one in the placebo group). Interpretation Neither EPA nor aspirin treatment were associated with a reduction in the proportion of patients with at least one colorectal adenoma. Further research is needed regarding the effect on colorectal adenoma number according to adenoma type and location. Optimal use of EPA and aspirin might need a precision medicine approach to adenoma recurrence. / Efficacy and Mechanism Evaluation Programme, a UK Medical Research Council and National Institute for Health Research partnership. / Research Development Fund Publication Prize Award winner, November 2018.
109

Colorectal polyp outcomes after participation in the seAFOod polyp prevention trial: Evidence of rebound elevated colorectal polyp risk after short-term aspirin use

05 October 2023 (has links)
Yes / The seAFOod polyp prevention trial was a randomised, placebo-controlled, 2 × 2 factorial trial of aspirin 300 mg and eicosapentaenoic acid (EPA) 2000 mg daily in individuals who had a screening colonoscopy in the English Bowel Cancer Screening Programme (BCSP). Aspirin treatment was associated with a 20% reduction in colorectal polyp number at BCSP surveillance colonoscopy 12 months later. It is unclear what happens to colorectal polyp risk after short-term aspirin use. To investigate colorectal polyp risk according to the original trial treatment allocation, up to 6 years after trial participation. All seAFOod trial participants were scheduled for further BCSP surveillance and provided informed consent for the collection of colonoscopy outcomes. We linked BCSP colonoscopy data to trial outcomes data. In total, 507 individuals underwent one or more colonoscopies after trial participation. Individuals grouped by treatment allocation were well matched for clinical characteristics, follow-up duration and number of surveillance colonoscopies. The polyp detection rate (PDR; the number of individuals who had ≥1 colorectal polyp detected) after randomization to placebo aspirin was 71.1%. The PDR was 80.1% for individuals who had received aspirin (odds ratio [OR] 1.13 [95% confidence interval 1.02, 1.24]; p = 0.02). There was no difference in colorectal polyp outcomes between individuals who had been allocated to EPA compared with its placebo (OR for PDR 1.00 [0.91, 1.10]; p = 0.92). Individuals who received aspirin in the seAFOod trial demonstrated increased colorectal polyp risk during post-trial surveillance. Rebound elevated neoplastic risk after short-term aspirin use has important implications for aspirin cessation driven by age-related bleeding risk. ISRCTN05926847. / Efficacy and Mechanism Evaluation Programme. Grant Number: NIHR128210.
110

Polymorphisms in Cyclooxygenase, Lipoxygenase and TP53 genes predict colorectal polyp risk reduction by aspirin in the seAFOod polyp prevention trial

02 November 2023 (has links)
Yes / Aspirin and eicosapentaenoic acid (EPA) reduce colorectal adenomatous polyp risk and affect synthesis of oxylipins including prostaglandin E2. We investigated whether 35 single nucleotide polymorphisms (SNPs) in oxylipin metabolism genes such as cyclooxygenase [PTGS] and lipoxygenase [ALOX], as well as 7 SNPs already associated with colorectal cancer (CRC) risk reduction by aspirin (eg. TP53; rs104522), modified the effects of aspirin and EPA on colorectal polyp recurrence in the randomised 2x2 factorial seAFOod trial. Treatment effects were reported as the incidence rate ratio (IRR) and 95% confidence interval (CI) by stratifying negative binomial and Poisson regression analyses of colorectal polyp risk on SNP genotype. Statistical significance was reported with adjustment for the false discovery rate as the P and q value. Five hundred and forty-two (of 707) trial participants had both genotype and colonoscopy outcome data. Reduction in colorectal polyp risk in aspirin users compared with non-aspirin users was restricted to rs4837960 (PTGS1) common homozygotes (IRR 0.69 [95%CI 0.53,0.90]; q=0.06), rs2745557 (PTGS2) compound heterozygote-rare homozygotes (IRR 0.60 [0.41,0.88]; q=0.06), rs7090328 (ALOX5) rare homozygotes (IRR 0.27 [0.11,0.64]; q=0.05), rs2073438 (ALOX12) common homozygotes (IRR 0.57 [0.41,0.80]; q=0.05), and rs104522 (TP53) rare homozygotes (IRR 0.37 [0.17,0.79]; q=0.06). No modification of colorectal polyp risk in EPA users was observed. In conclusion, genetic variants relevant to the proposed mechanism of action on oxylipins are associated with differential colorectal polyp risk reduction by aspirin in individuals who develop multiple colorectal polyps. SNP genotypes should be considered during development of personalised, predictive models of CRC chemoprevention by aspirin. / Funder(s): Efficacy and Mechanism Evaluation Programme (EME) Award Id(s): NIHR128210. Funder(s): NIHR Senior Investigator grant. Funder(s): Cancer Research UK (CRUK) Award Id(s): C23434/A24939. Funder(s): European Union-BBSRC (UK) Award Id(s): BB/P028233/1.

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