Matching Items (307)
Description
The field of art conservation has evolved parallel to scientific advancements and in response to changing social conditions. Methods have expanded from dusting the surface of a work to bombarding an image with x-rays in an effort to fulfill the ultimate goal of restoration: to return a piece of art to the state originally created by the artist. The process has become much easier and more complex with the introduction of analytical equipment that shifted the focus of the field away from maintenance towards academic study. This work illustrates the changes the field and demonstrates the application of scientific techniques to specific works.
ContributorsSanders, Hailey Jane (Author) / Fahlman, Besty (Thesis director) / Codell, Julie (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2015-05
Description
The 23-step total synthesis of dolastatin 16, a cyclic depsipeptide of marine origin, is presented. Included are syntheses of nonnatural amino acids dolamethylleuine and dolaphenvaline. The biological activity of the synthetic product differed from naturally isolated dolastatin 16, which may indicate the initial screening identified an inactive compound and the active one was not detected initially, or may be a result of the conformational dynamics induced by the proline residues. Additionally, a family of structural analogues to the bacillistatins, another cyclic marine depsipeptide, were synthesized. These were deemed the silstatins. 8 modifications were produced. The alterations aimed to introduce a heteroatomic residue for further derivatization, such as producing an antibody-drug conjugate. This introduction did in general decrease the neoplastic activity of these agents, as expected, but by modulating the lipophilicity of the compound we were able to salvage much of the potency of the bacillistatins while potentially allowing prodrug development.
ContributorsMacdonald, Christian B. (Author) / Pettit, George (Thesis director) / Wang, Xu (Committee member) / Melody, Noeleen (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2015-05
Description
As the prevalence of childhood obesity in the United States rises, opportunities for children to be physically active become more vital. One opportunity for physical activity involves children walking to and from school. However, children that live in areas with a pedestrian-unfriendly built environment and a low degree of walkability are less likely to be physically active and more likely to be overweight. The purpose of this study was to study walking routes from schools in low-income neighborhoods in Southwestern United States to a local community center. Walking routes from the three study schools (South Mountain High School, Percy Julian Middle School, and Rose Linda Elementary School) were determined by distance, popularity, and the presence of a major thoroughfare. Segments and intersections, which formed the routes, were randomly selected from each school's buffer region. The walking routes as a whole, along with the segments and intersections, were audited and scored using built environment assessments tools: MAPS, PEQI and Walkability Checklist. These scores were utilized to develop interactive mapping tools to visualize the quality of the routes, segments and intersections and identify areas for improvement. Results showed that the routes from Percy Julian to the Kroc Center were, overall, rated higher than routes from the other two schools. The highest scoring route, from the seven routes studied, was route 2 from Percy Julian to the Kroc Center along Broadway Road. South Mountain High School was overall the worst starting point for walking to the Kroc Center as those three walking routes were graded as the least walkable. Possible areas for improvement include installing traffic calming features along major thoroughfares and reducing the perceived risk to pedestrian safety by beautifying the community by planting greenery. Future directions include studying the built environment in South Phoenix communities that surround the Kroc Center.
ContributorsZeien, Justin Lee (Author) / Buman, Matthew (Thesis director) / Hekler, Eric (Committee member) / Fellows, Brian (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2015-05
Description
The Dorrance Center for Rare Childhood Disorders is a unique research division at TGen (The Translational Genomics Research Institute) that provides personalized care to children and young adults facing rare, undiagnosed diseases. TGen scientists believe that the answers to these enigmatic disorders can often be found in a person's genetic code. They aim to solve these genetic mysteries using whole exome sequencing, a method that prioritizes the protein-coding portion of the genome in the search for disease-causing variants. Unfortunately, a communication gap sometimes exists between the TGen scientists and the patients they serve. I have seen, first hand, the kind of confusion that this study elicits in the families of its participants. Therefore, for my thesis, I decided to create a booklet that is meant to provide some clarity as to what exactly The Dorrance Center for Rare Childhood Disorders does to help diagnose children with rare disorders. The purpose of the booklet is to dispel any confusion regarding the study by providing a general review of genetics and an application of these lessons to the relevant sequencing technology as well as a discussion of the causes and effects of genetic mutations that often times are linked to rare childhood disorders.
ContributorsCambron, Julia Claire (Author) / LaBelle, Jeffrey (Thesis director) / Huentelman, Matt (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Physical activity as a health or nutrition related intervention might stimulate appetite and increase hunger due to increased energy expenditure. This study analyzed the effect of a postprandial 15-minute walk on the hunger and energy intake of 10 obese, pre-diabetic adults. Subjects participated in three 4-hour trials: a walk treatment (consume highly glycemic meal, walk for 15 minutes at a moderate pace, and rest for 4 hours), a fiber treatment (consume highly glycemic meal enriched with soluble fiber and rest for 4 hours), and a control treatment (consume highly glycemic meal without fiber and rest for 4 hours). The effects of each treatment on hunger and energy intake were measured using a Likert scale analysis (ranging from "completely satisfied" to "extremely hungry") at 4 hours post-treatment and pre/ post 24-hour dietary logs. The results showed no significant increase or decrease on hunger or energy intake for both the walk and the fiber treatment compared to the control treatment. This denies the idea that physical activity might increase short-term hunger, and supports the use of physical activity as a viable nutrition related intervention tool.
ContributorsTerrell, Alayna Franci (Author) / Johnston, Carol (Thesis director) / Vega Lopez, Sonia (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2015-05
Description
Despite the 40-year war on cancer, very limited progress has been made in developing a cure for the disease. This failure has prompted the reevaluation of the causes and development of cancer. One resulting model, coined the atavistic model of cancer, posits that cancer is a default phenotype of the cells of multicellular organisms which arises when the cell is subjected to an unusual amount of stress. Since this default phenotype is similar across cell types and even organisms, it seems it must be an evolutionarily ancestral phenotype. We take a phylostratigraphical approach, but systematically add species divergence time data to estimate gene ages numerically and use these ages to investigate the ages of genes involved in cancer. We find that ancient disease-recessive cancer genes are significantly enriched for DNA repair and SOS activity, which seems to imply that a core component of cancer development is not the regulation of growth, but the regulation of mutation. Verification of this finding could drastically improve cancer treatment and prevention.
ContributorsOrr, Adam James (Author) / Davies, Paul (Thesis director) / Bussey, Kimberly (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
There has been an alarming rise in the prevalence of obesity which has been attributed to the paralleled rise in consumption of high-fat foods. It’s commonly accepted that high-fat diets can lead to increased weight gain, however not all fats have the same physiological action. This study primarily focuses on the effect of canola oil, a monounsaturated fat, on energy homeostasis and body composition when it’s given as a supplement to a high-fat diet composed of saturated fatty acid. Rodent models were divided into three dietary groups: 1) low-fat diet (LFD), 2) high-fat diet (HFD) and 3) canola oils supplemented HFD (HF+CAN). After 4 weeks of dietary intervention, samples of epididymal fat, perinephric fat, and liver were analyzed across the three groups to see if the changes in energy homeostasis could be explained by the cellular behavior and composition of these tissues. Interestingly, the supplement of canola oil appeared to reverse the deleterious effects of a saturated fat diet, reverting energy intake, body weight gain and adipose tissue sizes to that (if not lower than that) of the LFD group. The only exception to this effect was the liver: the livers remained larger and fattier than those of the HFD. This occurrence is possibly due to a decrease in free fatty acid uptake in the adipose tissues—resulting in smaller adipose tissue sizes—and increased fatty acid uptake in the liver. The mechanism by which this occurs has yet to be elucidated and will be the primary focus of upcoming studies on the effect of monounsaturated fat on other diets.
ContributorsZuo, Connie Wanda (Author) / Washo-Krupps, Delon (Thesis director) / Deviche, Pierre (Committee member) / Herman, Richard (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Patients who are infected with the human immunodeficiency virus (HIV) and who remain adherent to their highly active antiretroviral treatment (HAART) regimen are likely to achieve good virologic control over significant periods of time. Children who start with a low CD4 percentage (below 15%) are associated with adverse clinical outcomes and the risk of never increasing their CD4 counts to normal functioning levels. While adherent adult HIV patients have been studied frequently, this was a retrospective chart study that aimed to describe the immune reconstitution pattern for up to 16 years in virologically controlled pediatric patients who had been or who are currently being treated at the Bill Holt Clinic at Phoenix Children's Hospital. In the preliminary study, 35 patients met criteria for inclusion and three years later for this extension study 7 more were added while 17 of the initial patients were followed further because they have remained in care and virologically controlled. All 28 patients who achieved 5 years of viral suppression were >25% CD4. All 8 patients who achieved 12 years of viral suppression were >31% CD4. All patients who achieved 16 years of viral suppression were >41% CD4. After 12 years, the 8 patients who maintained viral suppression all had absolute CD4 counts of over 600 cells and additionally each had CD4/CD8 ratios greater than 1. Overall, the data shows immune system normalization for up to 16 years, although CD4/CD8 ratios improved but never completely normalized. Some limitations include a small sample size and missing data points due to laboratory testing errors or the lack of technology in different countries to test for CD8 cells. These findings suggest that children who remain adherent to HAART can experience ongoing immune healing for up to 16 years. This may provide additional incentive to providers and caretakers to encourage adherence and maximize long-term immune competence in HIV positive children.
ContributorsRichards, Anne Elizabeth (Author) / Wachter, Rebekka (Thesis director) / Blattman, Joseph (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
Background: Human papillomavirus (HPV) is the cause of 99.7% of cervical cancers. Research of cervical cancer has made this disease mostly curable in the developing world. Head and neck cancer, which is increasingly caused by HPV, still is associated with a mortality rate of 50,000 in the US annually. This study proposed to evaluate the biology of HPV-16 in head and neck tumors by using RT-qPCR to measure the RNA expression and its relation to physical status of the virus. Methods: This study was to develop an assay that uses RT-qPCR to determine the quantitative expression of HPV-16 RNA coding for proteins E1, E2, E4, E5, E6, and E7 in tumor samples. The assay development started with creation of primers. It went on to test the primers on template DNA through traditional PCR and then on DNA from HPV-16 positive cell lines, SiHa and CaSki, using RT-qPCR. This paper also describes the troubleshooting methods taken for the PCR reaction. Once the primers are verified, the RT-qPCR process can be carried out on RNA purified from tumor samples. Results: No primer sets have been confirmed to produce a product through PCR or RT-qPCR. The primer sequences match up correctly with known sequences for HPV-16 E1, E2, E4, E5, E6, and E7. RT-qPCR showed results consistent with the hypothesis. Conclusion: The RT-qPCR protocol must be optimized to confirm the primer sequences work as desired. Then primers will be used to study physical status and RNA expression in HPV-positive and HPV-negative head and neck tumor samples. This assay can help shed light on which proteins are expressed most in tumors of the head and neck and will aid in the development of future screening and treatment options.
ContributorsKhazanovich, Jakob (Author) / Anderson, Karen (Thesis director) / Mangone, Marco (Committee member) / Sundaresan, Sri Krishna (Committee member) / Barrett, The Honors College (Contributor)
Created2015-05
Description
Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disease characterized by progressive muscle loss and weakness. This disease arises from a mutation that occurs on a gene that encodes for dystrophin, which results in observable muscle death and inflammation; however, the genetic changes that result from dystrophin's dysfunctionality remain unknown. Current DMD research uses mdx mice as a model, and while very useful, does not allow the study of cell-autonomous transcriptome changes during the progression of DMD due to the strong inflammatory response, perhaps hiding important therapeutic targets. C. elegans, which has a very weak inflammatory response compared to mdx mice and humans, has been used in the past to study DMD with some success. The worm ortholog of the dystrophin gene has been identified as dys-1 since its mutation phenocopies the progression of the disease and a portion of the human dystrophin gene alleviates symptoms. Importantly, the extracted RNA transcriptome from dys-1 worms showed significant change in gene expression, which needs to be further investigated with the development of a more robust model. Our lab previously published a method to isolate high-quality muscle-specific RNA from worms, which could be used to study such changes at higher resolution. We crossed the dys-1 worms with our muscle-specific strain and demonstrated that the chimeric strain exhibits similar behavioral symptoms as DMD patients as characterized by a shortened lifespan, difficulty in movement, and a decrease in speed. The presence of dys-1 and other members of the dystrophin complex in the body muscle were supported by the development of a resulting phenotype due to RNAi knockdown of each component in the body muscle; however, further experimentation is needed to reinforce this conclusion. Thus, the constructed chimeric C. elegans strain possesses unique characteristics that will allow the study of genetic changes, such as transcriptome rearrangements and dysregulation of miRNA, and how they affect the progression of DMD.
ContributorsNguyen, Thuy-Duyen Cao (Author) / Mangone, Marco (Thesis director) / Newbern, Jason (Committee member) / Duchaine, Thomas (Committee member) / School of Social Transformation (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05