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Cardiovascular disease is one of the most deadly outcomes of end stage renal disease. Bioelectrical impedance is a intriguing, yet unproven method of measuring fluid buildup in the heart, and is marketed as a early diagnostic tool for onset of cardiovascular disease. In this study, selenium supplements were given to

Cardiovascular disease is one of the most deadly outcomes of end stage renal disease. Bioelectrical impedance is a intriguing, yet unproven method of measuring fluid buildup in the heart, and is marketed as a early diagnostic tool for onset of cardiovascular disease. In this study, selenium supplements were given to a cohort of dialysis patients in the Phoenix metro area and their fluid tolerance was measured with thoracic biolectrical impedance. BNP was used as a correlate to see if bioelectrical impedance was correlated with heart disease. The study found no correlation between BNP and bioelectrical impedance and thus was not an accurate diagnostic tool in a medical setting.
ContributorsBrown, Patrick Michael (Author) / Johnston, Carol (Thesis director) / Orchinik, Miles (Committee member) / Tingey, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2013-05
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Ephemeral and intermittent streams are valuable sources of surface water support in the arid ecosystems of the Southwestern United States. These streams account for over 80% of the streams in the American Southwest and their importance has been indicated in many studies. Ephemeral and intermittent streams support a wide range

Ephemeral and intermittent streams are valuable sources of surface water support in the arid ecosystems of the Southwestern United States. These streams account for over 80% of the streams in the American Southwest and their importance has been indicated in many studies. Ephemeral and intermittent streams support a wide range of plant and animal species in both continuous and episodic fashions. This study aimed to gain a better understanding of the relationship between streamflow permanence and patterns of biomass and secondary production of the riparian fauna these ecosystems support. This was accomplished through a yearlong survey in the Huachuca Mountains of Southeastern, Arizona where macroinvertebrates were collected at various sites along a gradient of streamflow permanence before, during, and after the three month monsoon season that supplies most of the annual rainfall in this region. The results of my surveys indicate that 1) Sites characterized by low streamflow permanence were more responsive to changes in precipitation than sites characterized by relatively high streamflow permanence 2) In ephemeral streams, there is a significant peak in terrestrial macroinvertebrate production and biomass both during and after the monsoon season 3) streamflow permanence may convey consistent but not exceptional secondary production whereas seasonality in rainfall may convey exceptional but episodic secondary production—more so in sites where streamflow is not consistent.
ContributorsMcCartin, Michael Patrick (Author) / Sabo, John (Thesis director) / Stromberg, Juliet (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
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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

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
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Studies of animal contests often focus solely on a single static measurement of fighting ability, such as the size or the strength of the individual. However, recent studies have highlighted the importance of individual variation in the dynamic behaviors used during a fight, such as, assessment strategies, decision making, and

Studies of animal contests often focus solely on a single static measurement of fighting ability, such as the size or the strength of the individual. However, recent studies have highlighted the importance of individual variation in the dynamic behaviors used during a fight, such as, assessment strategies, decision making, and fine motor control, as being strong predictors of the outcome of aggression. Here, I combined morphological and behavioral data to discover how these features interact during aggressing interactions in male virile crayfish, Faxonius virilis. I predicted that individual variation in behavioral skill for decision making (i.e., number of strikes thrown), would determine the outcome of contest success in addition to morphological measurements (e.g. body size, relative claw size). To evaluate this prediction, I filmed staged territorial interactions between male F. virilis and later analyzed trial behaviors (e.g. strike, pinches, and bout time) and aggressive outcomes. I found very little support for skill to predict win/loss outcome in trials. Instead, I found that larger crayfish engaged in aggression for longer compared to smaller crayfish, but that larger crayfish did not engage in a greater number of claw strikes or pinches when controlling for encounter duration. Future studies should continue to investigate the role of skill, by using finer-scale techniques such as 3D tracking software, which could track advanced measurements (e.g. speed, angle, and movement efficiency). Such studies would provide a more comprehensive understanding of the relative influence of fighting skill technique on territorial contests.

ContributorsNguyen, Phillip Huy (Author) / Angilletta, Michael (Thesis director) / McGraw, Kevin (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description
Pathogenic Gram-negative bacteria employ a variety of molecular mechanisms to combat host defenses. Two-component regulatory systems (TCR systems) are the most ubiquitous signal transduction systems which regulate many genes required for virulence and survival of bacteria. In this study, I analyzed different TCR systems in two clinically-relevant Gram-negative bacteria, i.e.,

Pathogenic Gram-negative bacteria employ a variety of molecular mechanisms to combat host defenses. Two-component regulatory systems (TCR systems) are the most ubiquitous signal transduction systems which regulate many genes required for virulence and survival of bacteria. In this study, I analyzed different TCR systems in two clinically-relevant Gram-negative bacteria, i.e., oral pathogen Porphyromonas gingivalis and enterobacterial Escherichia coli. P. gingivalis is a major causative agent of periodontal disease as well as systemic illnesses, like cardiovascular disease. A microarray study found that the putative PorY-PorX TCR system controls the secretion and maturation of virulence factors, as well as loci involved in the PorSS secretion system, which secretes proteinases, i.e., gingipains, responsible for periodontal disease. Proteomic analysis (SILAC) was used to improve the microarray data, reverse-transcription PCR to verify the proteomic data, and primer extension assay to determine the promoter regions of specific PorX regulated loci. I was able to characterize multiple genetic loci regulated by this TCR system, many of which play an essential role in hemagglutination and host-cell adhesion, and likely contribute to virulence in this bacterium. Enteric Gram-negative bacteria must withstand many host defenses such as digestive enzymes, low pH, and antimicrobial peptides (AMPs). The CpxR-CpxA TCR system of E. coli has been extensively characterized and shown to be required for protection against AMPs. Most recently, this TCR system has been shown to up-regulate the rfe-rff operon which encodes genes involved in the production of enterobacterial common antigen (ECA), and confers protection against a variety of AMPs. In this study, I utilized primer extension and DNase I footprinting to determine how CpxR regulates the ECA operon. My findings suggest that CpxR modulates transcription by directly binding to the rfe promoter. Multiple genetic and biochemical approaches were used to demonstrate that specific TCR systems contribute to regulation of virulence factors and resistance to host defenses in P. gingivalis and E. coli, respectively. Understanding these genetic circuits provides insight into strategies for pathogenesis and resistance to host defenses in Gram negative bacterial pathogens. Finally, these data provide compelling potential molecular targets for therapeutics to treat P. gingivalis and E. coli infections.
ContributorsLeonetti, Cori (Author) / Shi, Yixin (Thesis advisor) / Stout, Valerie (Committee member) / Nickerson, Cheryl (Committee member) / Sandrin, Todd (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Specificity and affinity towards a given ligand/epitope limit target-specific delivery. Companies can spend between $500 million to $2 billion attempting to discover a new drug or therapy; a significant portion of this expense funds high-throughput screening to find the most successful target-specific compound available. A more recent addition to discovering

Specificity and affinity towards a given ligand/epitope limit target-specific delivery. Companies can spend between $500 million to $2 billion attempting to discover a new drug or therapy; a significant portion of this expense funds high-throughput screening to find the most successful target-specific compound available. A more recent addition to discovering highly specific targets is the application of phage display utilizing single chain variable fragment antibodies (scFv). The aim of this research was to employ phage display to identify pathologies related to traumatic brain injury (TBI), particularly astrogliosis. A unique biopanning method against viable astrocyte cultures activated with TGF-β achieved this aim. Four scFv clones of interest showed varying relative affinities toward astrocytes. One of those four showed the ability to identify reactive astroctyes over basal astrocytes through max signal readings, while another showed a statistical significance in max signal reading toward basal astrocytes. Future studies will include further affinity characterization assays. This work contributes to the development of targeting therapeutics and diagnostics for TBI.
ContributorsMarsh, William (Author) / Stabenfeldt, Sarah (Thesis advisor) / Caplan, Michael (Committee member) / Sierks, Michael (Committee member) / Arizona State University (Publisher)
Created2013
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The goal of this thesis is to test whether Alzheimer's disease (AD) is associated with distinctive humoral immune changes that can be detected in plasma and tracked across time. This is relevant because AD is the principal cause of dementia, and yet, no specific diagnostic tests are universally employed in

The goal of this thesis is to test whether Alzheimer's disease (AD) is associated with distinctive humoral immune changes that can be detected in plasma and tracked across time. This is relevant because AD is the principal cause of dementia, and yet, no specific diagnostic tests are universally employed in clinical practice to predict, diagnose or monitor disease progression. In particular, I describe herein a proteomic platform developed at the Center for Innovations in Medicine (CIM) consisting of a slide with 10.000 random-sequence peptides printed on its surface, which is used as the solid phase of an immunoassay where antibodies of interest are allowed to react and subsequently detected with a labeled secondary antibody. The pattern of antibody binding to the microarray is unique for each individual animal or person. This thesis will evaluate the versatility of the microarray platform and how it can be used to detect and characterize the binding patterns of antibodies relevant to the pathophysiology of AD as well as the plasma samples of animal models of AD and elderly humans with or without dementia. My specific aims were to evaluate the emergence and stability of immunosignature in mice with cerebral amyloidosis, and characterize the immunosignature of humans with AD. Plasma samples from APPswe/PSEN1-dE9 transgenic mice were evaluated longitudinally from 2 to 15 months of age to compare the evolving immunosignature with non-transgenic control mice. Immunological variation across different time-points was assessed, with particular emphasis on time of emergence of a characteristic pattern. In addition, plasma samples from AD patients and age-matched individuals without dementia were assayed on the peptide microarray and binding patterns were compared. It is hoped that these experiments will be the basis for a larger study of the diagnostic merits of the microarray-based immunoassay in dementia clinics.
ContributorsRestrepo Jimenez, Lucas (Author) / Johnston, Stephen A. (Thesis advisor) / Chang, Yung (Committee member) / Reiman, Eric (Committee member) / Sierks, Michael (Committee member) / Arizona State University (Publisher)
Created2011
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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

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
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Description
Background: Coccidioidomycosis (Valley Fever) is a respiratory disease that is caused by the soil-dwelling fungi Coccidioides immitis and Coccidioides posadasii. Because fungal glycosylation patterns are distinct from mammalian glycosylation patterns, we hypothesized that certain lectins (carbohydrate-binding proteins) might have differential binding properties to coccidioidal glycoproteins, and therefore serve as a

Background: Coccidioidomycosis (Valley Fever) is a respiratory disease that is caused by the soil-dwelling fungi Coccidioides immitis and Coccidioides posadasii. Because fungal glycosylation patterns are distinct from mammalian glycosylation patterns, we hypothesized that certain lectins (carbohydrate-binding proteins) might have differential binding properties to coccidioidal glycoproteins, and therefore serve as a tool for the purification and characterization of these glycoproteins from patient specimens. Materials and Methods: To identify potential Coccidioides-binding lectins, lectin-based immunohistochemistry was performed using a panel of 21 lectins on lung tissue from human patients infected with Coccidioides. Enzyme-Linked Immunosorbent Assays (ELISAs) were used to confirm and test candidate Coccidioides-binding lectins for their ability to bind to proteins from antigen preparations of laboratory-grown Coccidioides. Inhibition IHC and ELISAs were used to confirm binding properties of these lectins. SDS-PAGE and mass spectrometry were performed on eluates from coccidioidal antigen preparations run through lectin-affinity chromatography columns to characterize and identify lectin-binding coccidioidal glycoproteins. Results: Two GlcNAc-binding lectins, GSLII and sWGA, bound specifically to spherules and endospores in infected human lung tissue, and not to adjacent lung tissue. The binding of these lectins to both Coccidioides proteins in lung tissue and to coccidioidal antigen preparations was confirmed to have lectin-like characteristics. SDS-PAGE analysis of eluates from lectin-affinity chromatography demonstrated that GSLII and sWGA bind to coccidioidal glycoproteins. Mass spectrometric identification of the top ten lectin affinity-purified glycoproteins demonstrated that GSLII and sWGA share affinity to a common set of coccidioidal glycoproteins. Conclusion: This is the first report of lectins that bind specifically to Coccidioides spherules and endospores in infected humans. These lectins may have the potential to serve as tools for a better method of detection and diagnosis of Valley Fever.
ContributorsChowdhury, Yasmynn (Author) / Lake, Douglas (Thesis director) / Grys, Thomas (Committee member) / Magee, Mitchell (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
Efforts to quantify the diversity of the T cell repertoire have generally been unsuccessful because not all factors accounting for diversity have been considered. In order to get an accurate representation of the T cell repertoire, one must incorporate analysis of germline gene diversity, diversity from somatic recombination, joining diversity

Efforts to quantify the diversity of the T cell repertoire have generally been unsuccessful because not all factors accounting for diversity have been considered. In order to get an accurate representation of the T cell repertoire, one must incorporate analysis of germline gene diversity, diversity from somatic recombination, joining diversity from N- and P- nucleotides, and TCR chain pairing diversity. Because of advances in high-throughput sequencing techniques, estimates have been able to account for diversity from TCR genes. However the ability to account for chain pairing diversity has been more difficult. In order to do so, single cell sorting techniques must be employed. These techniques, though effective, are time consuming and expensive. For this reason, no large-scale analyses have been done on the immune repertoires using these techniques. In this study, we propose a novel method for linking the two TCR chain sequences from an individual cell. DNA origami nanostructure technology is employed to capture and bind the TCRγ and TCRδ chain mRNA inside individual cells using probe strands complementary to the C-region of those sequences. We then use a dual-primer RT and ligation molecular strategy to link the two sequences together. The result is a single amplicon containing the CDR3 region of the TCRγ and TCRδ. This amplicon can then be easily PCR amplified using sequence specific primers, and sequenced. DNA origami nanostructures offer a rapid, cost-effective method alternative to conventional single cell sorting techniques, as both TCR mRNA can be captured on one origami molecule inside a single cell. At present, this study outlines a proof-of-principle analysis of the method to determine its functionality. Using known TCRγ and TCRδ sequences, the DNA origami and RT/PCR method was tested and resulting sequence data proved the effectiveness of the method. The original TCRγ and TCRδ sequences were linked together as a single amplicon containing both CDR3 regions of the genes. Thus, this method can be employed in further research to elucidate the γδ T cell repertoire. This technology is also easily adapted to any gene target or cell type and therefore presents a large opportunity to be used in other immune repertoire analysis and other immunological studies (such as the rapid identification and subsequent production of antibodies).
ContributorsPoindexter, Morgan Elizabeth (Author) / Blattman, Joseph (Thesis director) / Yan, Hao (Committee member) / Schoettle, Louis (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05