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The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in a single fly that would allow for simultaneous expression of the oncogene and, in <br/>the surrounding cells, other genes of interest. This system would help establish Drosophila as a <br/>more versatile and reliable model organism for cancer research. Furthermore, pilot studies were <br/>performed, using elements of the final proposed system, to determine if tumor growth is possible <br/>in the center of the disc, which oncogene produces the best results, and if oncogene expression <br/>induced later in development causes tumor growth. Three different candidate genes were <br/>investigated: RasV12, PvrACT, and Avli.
One of the largest problems facing modern medicine is drug resistance. Many classes of drugs can be rendered ineffective if their target is able to acquire beneficial mutations. While this is an excellent showcase of the power of evolution, it necessitates the development of increasingly stronger drugs to combat resistant pathogens. Not only is this strategy costly and time consuming, it is also unsustainable. To contend with this problem, many multi-drug treatment strategies are being explored. Previous studies have shown that resistance to some drug combinations is not possible, for example, resistance to a common antifungal drug, fluconazole, seems impossible in the presence of radicicol. We believe that in order to understand the viability of multi-drug strategies in combating drug resistance, we must understand the full spectrum of resistance mutations that an organism can develop, not just the most common ones. It is possible that rare mutations exist that are resistant to both drugs. Knowing the frequency of such mutations is important for making predictions about how problematic they will be when multi-drug strategies are used to treat human disease. This experiment aims to expand on previous research on the evolution of drug resistance in S. cerevisiae by using molecular barcodes to track ~100,000 evolving lineages simultaneously. The barcoded cells were evolved with serial transfers for seven weeks (200 generations) in three concentrations of the antifungal Fluconazole, three concentrations of the Hsp90 inhibitor Radicicol, and in four combinations of Fluconazole and Radicicol. Sequencing data was used to track barcode frequencies over the course of the evolution, allowing us to observe resistant lineages as they rise and quantify differences in resistance evolution across the different conditions. We were able to successfully observe over 100,000 replicates simultaneously, revealing many adaptive lineages in all conditions. Our results also show clear differences across drug concentrations and combinations, with the highest drug concentrations exhibiting distinct behaviors.
Suicide is one of the leading causes of death worldwide and statistical analysis of suicide by profession reveals that physicians and veterinarians experience abnormally high suicide rates. This paper seeks to provide a comprehensive literature review over what some general theories of suicide are, why these professions exhibit high suicide rates, what assistance is currently being provided, and where do these assistance efforts succeed or fail. Moreover, this paper addresses what advancements may be made within these fields to further combat suicide in physicians and veterinarians. To achieve this, general theories behind suicide, risk factors unique to or heavily prevalent in these professions, and current assistance efforts are read, organized, and summarized.<br/><br/>A summary of these risk factors includes stress and mental health disorders accumulated through school and work, personal and professional isolation, access to lethal substances, suicide contagion, exposure to euthanasia, and the role of perfectionism. There are several assistance efforts in place with the most successful ones being highly personalized, but many are still underutilized. Moreover, the stigma of suicide pervades these professions and is addressed by several researchers as something to combat or prevent. Going forward, it is hopeful that not only will more assistance efforts will be created and provided for physicians and veterinarians suffering from suicidal tendencies, but efforts to reduce the stigma of suicide be implemented and utilized as soon as possible.