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- All Subjects: Obesity
- All Subjects: Molecular Biology
- Creators: School of Life Sciences
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
- Resource Type: Text
Description
Dogs' health and wellbeing is of great importance to their owners. The most common nutritional problem for pet dogs is obesity, with 22-40% of pet dogs being classified as overweight or obese. With many adverse health effects associated with obesity, this is a major concern for owners and veterinarians. The degree to which dogs enjoy consuming certain foods can have substantial implications for their body weight, so it is important to understand which aspects of foods make them appealing to dogs. This study aimed to determine whether nutritional aspects of commercial dog foods predict dogs' preferences for those foods. It was found that consumption preference is positively correlated with protein content (p < .001), therefore implying that the protein content of commercial dry dog foods may predict dogs' consumption preferences. Consumption preferences were not predicted by other available measures of food content or caloric value. Dogs' preference for foods high in protein content may be due to the satiating effect of protein. Since foods high in protein both reduce the amount of energy consumed and are found to be palatable to dogs, high-protein dog foods may offer a way for dog food manufacturers, veterinarians, and pet owners to combat obesity in pet dogs.
ContributorsPrevost, Emily Danielle (Author) / Wynne, Clive (Thesis director) / Hall, Nathaniel (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (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
Alternative polyadenylation (APA) is the biological mechanism in which the same gene can have multiple 3'untranslated region (3'UTR) isoforms due to the presence of multiple polyadenylation signal (PAS) elements within the pre mRNAs. Because APA produces mRNA transcripts that have different 3'UTR isoforms, certain transcripts may be subject to post-transcriptional regulation by regulatory non-coding RNAs, such as microRNAs or RNA binding proteins defects of which have been implicated in diseases such as cancer. Despite the increasing level of information, functional understanding of the molecular mechanisms involved in transcription is still poorly understood, nor is it clear why APA is necessary at a cell or tissue-specific level. To address these questions I wanted to develop a set of sensor strain plasmids capable of detecting cleavage and polyadenylation in vivo, inject the complete sensor strain plasmid into C. elegans and prepare stable transgenic lines, and perform proof-of-principle RNAi feeding experiments targeting genes associated with the cleavage and polyadenylation complex machinery. I demonstrated that it was possible to create a plasmid capable of detecting cleavage and polyadenylation in C. elegans; however, issues arose during the RNAi assays indicating the sensor strain plasmid was not sensitive enough to the RNAi to effectively detect in the worms. Once the problems involved with sensitivity and variability in the RNAi effects are resolved, the plasmid would be able to better address questions regarding the functional understanding of molecular mechanisms involved in transcription termination.
ContributorsWilky, Henry Patrick (Author) / Mangone, Marco (Thesis director) / Newbern, Jason (Committee member) / Blazie, Stephen (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Introduction: Human papillomavirus (HPV) infection is seen in up to 90% of cases of cervical cancer, the third leading cancer cause of death in women. Current HPV screening focuses on only two HPV types and covers roughly 75% of HPV-associated cervical cancers. A protein based assay to test for antibody biomarkers against 98 HPV antigens from both high and low risk types could provide an inexpensive and reliable method to screen for patients at risk of developing invasive cervical cancer. Methods: 98 codon optimized, commercially produced HPV genes were cloned into the pANT7_cGST vector, amplified in a bacterial host, and purified for mammalian expression using in vitro transcription/translation (IVTT) in a luminescence-based RAPID ELISA (RELISA) assay. Monoclonal antibodies were used to determine immune cross-reactivity between phylogenetically similar antigens. Lastly, several protein characteristics were examined to determine if they correlated with protein expression. Results: All genes were successfully moved into the destination vector and 86 of the 98 genes (88%) expressed protein at an adequate level. A difference was noted in expression by gene across HPV types but no correlation was found between protein size, pI, or aliphatic index and expression. Discussion: Further testing is needed to express the remaining 12 HPV genes. Once all genes have been successfully expressed and purified at high concentrations, DNA will be printed on microscope slides to create a protein microarray. This microarray will be used to screen HPV-positive patient sera for antibody biomarkers that may be indicative of cervical cancer and precancerous cervical neoplasias.
ContributorsMeshay, Ian Matthew (Author) / Anderson, Karen (Thesis director) / Magee, Mitch (Committee member) / Katchman, Benjamin (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Understanding glycosaminoglycans’ (GAG) interaction with proteins is of growing interest for therapeutic applications. For instance, heparin is a GAG exploited for its ability to inhibit proteases, therefore inducing anticoagulation. For this reason, heparin is extracted in mass quantities from porcine intestine in the pharmaceutical field. Following a contamination in 2008, alternative sources for heparin are desired. In response, much research has been invested in the extraction of the naturally occurring polysaccharide, heparosan, from Escherichia coli K5 strain. As heparosan contains the same structural backbone as heparin, modifications can be made to produce heparin or heparin-like molecules from this source. Furthermore, isotopically labeled batches of heparosan can be produced to aid in protein-GAG interaction studies. In this study, a comparative look between extraction and purification methods of heparosan was taken. Fed-batch fermentation of this E. coli strain followed by subsequent purification yielded a final 13C/15N labeled batch of 90mg/L of heparosan which was then N-sulfated. Furthermore, a labeled sulfated disaccharide from this batch was utilized in a protein interaction study with CCL5. With NMR analysis, it was found that this heparin-like molecule interacted with CCL5 when its glucosamine residue was in a β-conformation. This represents an interaction reliant on a specific anomericity of this GAG molecule.
ContributorsHoffman, Kristin Michelle (Author) / Wang, Xu (Thesis director) / Cabirac, Gary (Committee member) / Morgan, Ashli (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
This project explores a variety of ways of framing the problem of obesity, beginning with a multidisciplinary assessment of genetic, environmental, cultural, nutritional, and socioeconomic factors involved in the structure and the consequences of each frame. How obesity is framed as a problem has a profound impact on the kinds of solutions that may be deemed scientifically appropriate. But frames are not entirely evidence-based, inasmuch as political and moral values infuse debates about the nature of obesity. Drawing on interdisciplinary resources from bioethics and the philosophy of science, I strive to offer strategic insight in to how to navigate the complexity of these issues.
ContributorsYanamandra, Meghana (Author) / Robert, Jason (Thesis director) / Wharton, Christopher (Committee member) / Drago, Mary (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2014-05
Description
Nucleic acids encode the information required to create life, and polymerases are the gatekeepers charged with maintaining the storage and flow of this genetic information. Synthetic biologists utilize this universal property to modify organisms and other systems to create unique traits or improve the function of others. One of the many realms in synthetic biology involves the study of biopolymers that do not exist naturally, which is known as xenobiology. Although life depends on two biopolymers for genetic storage, it may be possible that alternative molecules (xenonucleic acids – XNAs), could be used in their place in either a living or non-living system. However, implementation of an XNA based system requires the development of polymerases that can encode and decode information stored in these artificial polymers. A strategy called directed evolution is used to modify or alter the function of a protein of interest, but identifying mutations that can modify polymerase function is made problematic by their size and overall complexity. To reduce the amount of sequence space that needs to be samples when attempting to identify polymerase variants, we can try to make informed decisions about which amino acid residues may have functional roles in catalysis. An analysis of Family B polymerases has shown that residues which are involved in substrate specificity are often highly conserved both at the sequence and structure level. In order to validate the hypothesis that a strong correlation exists between structural conservation and catalytic activity, we have selected and mutated residues in the 9°N polymerase using a loss of function mutagenesis strategy based on a computational analysis of several homologues from a diverse range of taxa. Improvement of these models will hopefully lead to quicker identification of loci which are ideal engineering targets.
ContributorsHaeberle, Tyler Matthew (Author) / Chaput, John (Thesis director) / Chen, Julian (Committee member) / Larsen, Andrew (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
The Intercellular Adhesion Molecule-1 (ICAM-1, known as CD54) is a cell surface type I transmembrane glycoprotein with a molecular weight of 85 to 110 kDa. The primary function of ICAM-1 is to provide adhesion between endothelial cells and leukocytes after injury or stress. ICAM-1 is used as a receptor for various pathogens such as rhinoviruses, coxsackievirus A21 and the malaria parasite Plasmodium falciparum. ICAM-1 contains five immunoglobulin (Ig) domains in its long N-terminal extracellular region, a hydrophobic transmembrane domain, and a small C-terminal cytoplasmic domain. The Ig domains 1-2 and Ig domains 3-4-5 have been crystallized separately and their structure solved, however the full ICAM-1 structure has not been solved. Because ICAM-1 appears to be important for the mediation of cell-to-cell communication in physiological and pathological conditions, gaining a structural understanding of the full-length membrane anchored ICAM-1 is desirable. In this context, we have transiently expressed a plant-optimized gene encoding human ICAM-1 in Nicotiana benthamiana plants using the MagnICON expression system. The plant produced ICAM-1 is forming aggregates according to previous data. Thus, the current extraction and purification protocols have been altered to include TCEP, a reducing agent. The protein was purified using TALON metal affinity resin and partially characterized using various biochemical techniques. Our results show that there is a reduction in aggregation formation with the use of TCEP.
ContributorsPatel, Heeral (Author) / Mor, Tsafrir (Thesis director) / Mason, Hugh (Committee member) / Kannan, Latha (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Obesity is a growing issue in the Western world, as well as other international countries. This is leading to increases in complications associated with obesity. One such complication is osteoarthritis (OA) of load bearing joints that requires surgical treatment by total knee arthroplasty (TKA). Obesity is also associated with an increase in surgical complications that may lead to poor TKA outcomes. Additionally, the female gender is also known to be associated with increased rates of severe, clinical OA. This study was designed to determine the comparative efficacy of two knee implants in the obese female population through retrospective chart review and data analysis. The implants differ in their level of constraint, with the total stabilizing (TS) being more constrained than the posterior stabilizing (PS). We hypothesized that the TS implants would be associated with improved functional outcomes in the obese female population. The TS implant was observed to be associated with earlier improvement of both passive and active range of motion. This implant also showed greater improvement from pre-operative condition in stability, rejecting our null hypothesis and supporting our hypothesis.
ContributorsWorhacz, Kellen Michael (Author) / Hinrichs, Richard (Thesis director) / Jacofsky, Marc (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Variants of human butyrylcholinesterase (BChE) have been designed to have high cocaine hydrolytic activity. These variants have potential pharmacological applications toward treating cocaine overdose and addiction. These enzymes must be stable in the human body over fairly long periods of time in order to be effective at treating cocaine addiction. Recombinantly expressed BChE, however, tends to be in monomer or dimer oligomeric forms, which are far less stable than the tetramer form of the enzyme. When BChE is transiently expressed in Nicotiana benthamiana, it is produced mainly as monomers and dimers. However, when the protein is expressed through stable transformation, it produces much greater proportions of tetramers. Tetramerization of WT human plasma derived BChE is facilitated by the binding of a proline rich peptide. In this thesis, I investigated if a putative plant-derived analog of the mammalian proline-rich attachment domain caused stably expressed cocaine hydrolase variants of human BChE to undergo tetramerization. I also examined if co-expression of peptides with known proline-rich attachment domains further shifted the monomer-tetramer ratio toward the tetramer.
ContributorsKendle, Robert Player (Author) / Mor, Tsafrir (Thesis director) / Mason, Hugh (Committee member) / Larrimore, Kathy (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05