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- All Subjects: Evolution
- All Subjects: healthcare
- Creators: School of Life Sciences
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
- Status: Published
Description
Many factors are at play within the genome of an organism, contributing to much of the diversity and variation across the tree of life. While the genome is generally encoded by four nucleotides, A, C, T, and G, this code can be expanded. One particular mechanism that we examine in this thesis is modification of bases—more specifically, methylation of Adenine (m6A) within the GATC motif of Escherichia coli. These methylated adenines are especially important in a process called methyl-directed mismatch repair (MMR), a pathway responsible for repairing errors in the DNA sequence produced by replication. In this pathway, methylated adenines identify the parent strand and direct the repair proteins to correct the erroneous base in the daughter strand. While the primary role of methylated adenines at GATC sites is to direct the MMR pathway, this methylation has also been found to affect other processes, such as gene expression, the activity of transposable elements, and the timing of DNA replication. However, in the absence of MMR, the ability of these other processes to maintain adenine methylation and its targets is unknown.
To determine if the disruption of the MMR pathway results in the reduced conservation of methylated adenines as well as an increased tolerance for mutations that result in the loss or gain of new GATC sites, we surveyed individual clones isolated from experimentally evolving wild-type and MMR-deficient (mutL- ;conferring an 150x increase in mutation rate) populations of E. coli with whole-genome sequencing. Initial analysis revealed a lack of mutations affecting methylation sites (GATC tetranucleotides) in wild-type clones. However, the inherent low mutation rates conferred by the wild-type background render this result inconclusive, due to a lack of statistical power, and reveal a need for a more direct measure of changes in methylation status. Thus as a first step to comparative methylomics, we benchmarked four different methylation-calling pipelines on three biological replicates of the wildtype progenitor strain for our evolved populations.
While it is understood that these methylated sites play a role in the MMR pathway, it is not fully understood the full extent of their effect on the genome. Thus the goal of this thesis was to better understand the forces which maintain the genome, specifically concerning m6A within the GATC motif.
To determine if the disruption of the MMR pathway results in the reduced conservation of methylated adenines as well as an increased tolerance for mutations that result in the loss or gain of new GATC sites, we surveyed individual clones isolated from experimentally evolving wild-type and MMR-deficient (mutL- ;conferring an 150x increase in mutation rate) populations of E. coli with whole-genome sequencing. Initial analysis revealed a lack of mutations affecting methylation sites (GATC tetranucleotides) in wild-type clones. However, the inherent low mutation rates conferred by the wild-type background render this result inconclusive, due to a lack of statistical power, and reveal a need for a more direct measure of changes in methylation status. Thus as a first step to comparative methylomics, we benchmarked four different methylation-calling pipelines on three biological replicates of the wildtype progenitor strain for our evolved populations.
While it is understood that these methylated sites play a role in the MMR pathway, it is not fully understood the full extent of their effect on the genome. Thus the goal of this thesis was to better understand the forces which maintain the genome, specifically concerning m6A within the GATC motif.
ContributorsBoyer, Gwyneth (Author) / Lynch, Michael (Thesis director) / Behringer, Megan (Committee member) / Geiler-Samerotte, Kerry (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Physician-assisted suicide occurs when a physician facilitates a patient's death by prescribing a lethal medication that they understand will be used for the purpose of ending the patient's life. It is a highly contentious subject and, with the recent addition of California to the list of states that allow physician-assisted suicide, is an increasingly relevant subject. Physician-assisted suicide is rarely framed as a healthcare experience, despite being a choice in the process of end-of-life care. The research seeks to bring together the debates about physician-assisted suicide with conversations about health care experiences. The experiences and perspectives of young people are particularly valuable to evaluate now, as their voices will soon be the leaders in the debate over physician-assisted suicide. Within this research, there is an underlying theme of independence of individuals that is present through both the literature review and the body of data collected and analyzed. The study found that there was no significant relationship between the quality of a person's healthcare and their perspectives about physician-assisted suicide.
ContributorsMoeur, Katherine Elizabeth (Author) / Brian, Jennifer (Thesis director) / Graff, Sarah (Committee member) / Stevenson, Christine (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Many bacteria actively import environmental DNA and incorporate it into their genomes. This behavior, referred to as transformation, has been described in many species from diverse taxonomic backgrounds. Transformation is expected to carry some selective advantages similar to those postulated for meiotic sex in eukaryotes. However, the accumulation of loss-of-function alleles at transformation loci and an increased mutational load from recombining with DNA from dead cells create additional costs to transformation. These costs have been shown to outweigh many of the benefits of recombination under a variety of likely parameters. We investigate an additional proposed benefit of sexual recombination, the Red Queen hypothesis, as it relates to bacterial transformation. Here we describe a computational model showing that host-pathogen coevolution may provide a large selective benefit to transformation and allow transforming cells to invade an environment dominated by otherwise equal non-transformers. Furthermore, we observe that host-pathogen dynamics cause the selection pressure on transformation to vary extensively in time, explaining the tight regulation and wide variety of rates observed in naturally competent bacteria. Host-pathogen dynamics may explain the evolution and maintenance of natural competence despite its associated costs.
ContributorsPalmer, Nathan David (Author) / Cartwright, Reed (Thesis director) / Wang, Xuan (Committee member) / Sievert, Chris (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This study investigates how the patient-provider relationship between lesbian, gay, and bisexual women and their healthcare providers influences their access to, utilization of, and experiences within healthcare environments. Nineteen participants, ages 18 to 34, were recruited using convenience and snowball sampling. Interviews were conducted inquiring about their health history and their experiences within the healthcare system in the context of their sexual orientation. The data collected from these interviews was used to create an analysis of the healthcare experiences of those who identify as queer. Although the original intention of the project was to chronicle the experiences of LGB women specifically, there were four non-binary gender respondents who contributed interviews. In an effort to not privilege any orientation over another, the respondents were collectively referred to as queer, given the inclusive and an encompassing nature of the term. The general conclusion of this study is that respondents most often experienced heterosexism rather than outright homophobia when accessing healthcare. If heterosexism was present within the healthcare setting, it made respondents feel uncomfortable with their providers and less likely to inform them of their sexuality even if it was medically relevant to their health outcomes. Gender, race, and,socioeconomic differences also had an effect on the patient-provider relationship. Non-binary respondents acknowledged the need for inclusion of more gender options outside of male or female on the reporting forms often seen in medical offices. By doing so, medical professionals are acknowledging their awareness and knowledge of people outside of the binary gender system, thus improving the experience of these patients. While race and socioeconomic status were less relevant to the context of this study, it was found that these factors have an affect on the patient-provider relationship. There are many suggestions for providers to improve the experiences of queer patients within the healthcare setting. This includes nonverbal indications of acknowledgement and acceptance, such as signs in the office that indicate it to be a queer friendly space. This will help in eliminating the fear and miscommunication that can often happen when a queer patient sees a practitioner for the first time. In addition, better education on medically relevant topics to queer patients, is necessary in order to eliminate disparities in health outcomes. This is particularly evident in trans health, where specialized education is necessary in order to decrease poor health outcomes in trans patients. Future directions of this study necessitate a closer look on how race and socioeconomic status have an effect on a queer patient's relationship with their provider.
ContributorsRajan, Sindhu (Co-author) / Bradley, Arianna (Co-author) / Larson, Michelle (Co-author) / Alvarado, Aimee (Co-author) / Ingram-Waters, Mary (Thesis director) / Arnold, Michelle (Committee member) / School of Molecular Sciences (Contributor) / School of Social Transformation (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / College of Public Service and Community Solutions (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Healthcare systems and health insurance are both concepts implemented in every country to provide access to the general population. Countries undergo healthcare reforms in order to increase the performance of the system. In 2010, the Affordable Care Act (ACA) was introduced in the United States to increase coverage and create a more inclusive health insurance market. For comparison, the recent reforms in Chile and Singapore were observed as points to determine what concepts work well and what can be implemented in the U.S. system. Unlike the United States, Chile and Singapore completely altered the system that was previously in use. In Chile, the reforms began in the 1970s and made two more major changes in 1973 and early 2000s. Singapore began its reform in the 1960s and created the medical savings account system that is still in use today. To analyze the system further, the medical professions of neurology, physician assistants and optometry were compared in each country. In regards to neurology, the coverage of services in Chile and Singapore are similar in that select medical procedures are covered. In contrast, the United States offers coverage on a case-by-case basis. For physician assistants, such a profession does not exist in Chile or Singapore. In the United States, the profession is rapidly expanding, and coverage is offered for most services provided. Optometry is a stand-alone profession in both the U.S. and Singapore. The services provided by the optometrists are selectively covered by insurance, depending on whether it is considered a medical problem. Chile covers the services often provided by optometrists, however, the ophthalmologist is the provider, as optometry does not exist. This study concluded that the U.S. should continue to provide a more inclusive healthcare system that includes vision and dental care. The U.S., like Singapore, should also adopt a more integrative system. Under this system, patient care would be provided in a way that professionals specializing in the care are included in every step of the process.
ContributorsLa, Jenny (Co-author) / Feruj, Farihah (Co-author) / Morrison, Sarah (Co-author) / Gaughan, Monica (Thesis director) / Essary, Alison (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Emerging Information Technology, Storage and Evaluation within Healthcare: A Discerning IMT Analysis
Description
The introduction of novel information technology within contemporary healthcare settings presents a critical juncture for the industry and thus lends itself to the importance of better understanding the impact of this emerging "health 2.0" landscape. Simply, how such technology may affect the healthcare system is still not fully realized, despite the ever-growing need to adopt it in order to serve a growing patient population. Thus, two pertinent questions are posed: is HIT useful and practical and, if so, what is the best way to implement it? This study examined the clinical implementation of specific instances of health information technology (HIT) so as to weigh its benefits and risks to ultimately construct a proposal for successful widespread adoption. Due to the poignancy of information analysis within HIT, Information Measurement Theory (IMT) was used to measure the effectiveness of current HIT systems as well as to elucidate improvements for future implementation. The results indicate that increased transparency, attention to patient-focused approaches and proper IT training will not only allow HIT to better serve the community, but will also decrease inefficient healthcare expenditure.
ContributorsMaietta, Myles Anthony (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
We examined the evolutionary morphological responses of Drosophila melanogaster that had evolved at constant cold (16°), constant hot (25°C), and fluctuating (16° and 25°C). Flies that were exposed to the constant low mean temperature developed larger thorax, wing, and cell sizes than those exposed to constant high mean temperatures. Males and females both responded similarly to thermal treatments in average wing and cell size. The resulting cell area for a given wing size in thermal fluctuating populations remains unclear and remains a subject for future research.
ContributorsAdrian, Gregory John (Author) / Angilletta, Michael (Thesis director) / Harrison, Jon (Committee member) / Rusch, Travis (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
With advances in biotechnology, personalized medicine has become an ever-expanding field. Even with so much growth, the critics equally match the proponents of personalized medicine. The source of their disagreement is rooted in the concept of empowerment. This analysis utilizes the personal genomics company 23andMe and their relationship with the Federal Food and Drug Administration to illustrate varying views of empowerment. Specifically, the case study focuses on the ability to provide direct-to-consumer health reports to patients independent of physicians. In doing this, larger issues of what is at stake in personalized medicine are uncovered. These include but are not limited to: who determines what individuals get empowered and what information is determined good versus bad.
ContributorsSilverman, Adam Mattern (Author) / Brian, Jennifer (Thesis director) / Hurlbut, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Department of Psychology (Contributor)
Created2015-05
Description
Since its discovery in 1524, many people have characterized the vermiform appendix. Charles Darwin considered the human appendix to be a vestige and a useless structure. Others at the time opposed this hypothesis. However, Darwin's hypothesis became prevalent one until recently when there became a renewed interest in the appendix because of advancements in microscopes, knowledge of the immune system, and phylogenetics. In this review, I will argue that the vermiform appendix, although still not completely understood, has important functions. First, I will give the anatomy of the appendix. I will discuss the comparative anatomy between different animals and also primates. I will address the effects of appendicitis and appendectomy. I will give background on vestigial structures and will discuss if the appendix is a vestige. Following, I will review the evolution of the appendix. Finally, I will argue that the function of the appendix is as an immune organ, including discussion of gut-associated lymphoid tissue (GALT), development of lymphoid follicles in GALT and their comparison within different organs, Immunoglobulin A (IgA) function in the gut, biofilms as evidence that the appendix is a safe-house for beneficial bacteria, re-inoculation of the bowel, and protection against recurring infection. I will conclude with future studies that should be conducted to further our understanding of the vermiform appendix.
ContributorsPrestwich, Shelby Elizabeth (Author) / Cartwright, Reed (Thesis director) / Lynch, John (Committee member) / Furstenau, Tara (Committee member) / School of Geographical Sciences and Urban Planning (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This study looked into the cultural competency of physicians when interacting with patients who identify themselves as part of the Deaf and Hard of Hearing community. Through the course of this paper, it was found that the language barrier between these two communities played a large role in healthcare disparities for the D/HoH community. The language and culture barrier contributed to the misconceptions that are commonly found in the hearing world about the Deaf community, including assumptions about Deaf patients' opinion on their hearing loss, the efficacy of yelling, and the notion that all Deaf people can lip read with 100% accuracy. In addition, the perspectives of both the healthcare professionals and D/HoH patients was analyzed. Finally, the efficacy of current hospitals solutions for the language barrier was evaluated, particularly the use of video interpreting in hospital settings. More lasting solutions were proposed as an extension of this study, with an emphasis on education in all field of healthcare.
ContributorsHernandez, Deborah Andrea (Author) / O'Brien, Robin (Thesis director) / Howard, Pamela (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05