Colorectal adenomas are precursors of most colorectal cancers and are consequently a surrogate endpoint for assessing the efficacy of chemopreventive agents. Cyclooxygenase-2 (COX-2) levels have been found to be increased in a significant number of colorectal carcinomas and adenomas. COX-2 overexpression is linked to carcinogenesis due to increased production of prostaglandins, which seem to play an important role in angiogenesis, cell proliferation and migration, as well as in apoptosis. These data support the use of acetylsalicylic acid (AAS) or aspirin, a COX-2 inhibitor, as an effective agent in colorectal cancer prevention. Several cohort and case control studies have shown that regular use of aspirin reduces the risk of colorectal cancer by approximately 50%. However, randomized controlled trials of aspirin report discrepant results, although there is an decrease in the relative risk of adenoma recurrence of approximately 17%. To date, although there is compelling evidence that the use of aspirin protects against adenoma and colorectal cancer, the optimal dose and duration of aspirin required to obtain this effect remain to be defined. Probably, the longer the treatment duration--even for more than 10 years--and possibly with higher doses, the greater the protective effects of aspirin. Finally, these benefits need to be considered in the context of all of the health effects of prolonged aspirin use, both positive and negative.
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Journal of Visualized Experiments
What is Visualize?
JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.
How does it work?
We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.
Video X seems to be unrelated to Abstract Y...
In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.