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Approximately 248 million people in the world are currently living with chronic Hepatitis B virus (HBV) infection. HBV and HCV infections are the primary cause of liver diseases such as cirrhosis and hepatocellular carcinomas in the world with an estimated 1.4 million deaths annually. HBV in the Republic of Peru was used as a case study of an emerging and rapidly spreading disease in a developing nation. Wherein, clinical diagnosis of HBV infections in at-risk communities such the Amazon Region and the Andes Mountains are challenging due to a myriad of reasons. High prices of clinical diagnosis and limited access to treatment are alone the most significant deterrent for individuals living in at-risk communities to get the much need help. Additionally, limited testing facilities, lack of adequate testing policies or national guidelines, poor laboratory capacity, resource-limited settings, geographical isolation, and public mistrust are among the chief reasons for low HBV testing. Although, preventative vaccination programs deployed by the Peruvian health officials have reduced the number of infected individuals by year and region. To significantly reduce or eradicate HBV in hyperendemic areas and countries such as Peru, preventative clinical diagnosis and vaccination programs are an absolute necessity. Consequently, the need for a portable low-priced diagnostic platform for the detection of HBV and other diseases is substantial and urgent not only in Peru but worldwide. Some of these concerns were addressed by designing a low-cost, rapid detection platform. In that, an immunosignature technology (IMST) slide used to test for reactivity against the presence of antibodies in the serum-sample was used to test for picture resolution and clarity. IMST slides were scanned using a smartphone camera placed on top of the designed device housing a circuit of 32 LED lights at 647 nm, an optical magnifier at 15X, and a linear polarizing film sheet. Tow 9V batteries powered the scanning device LED circuit ensuring enough lighting. The resulting pictures from the first prototype showed that by lighting the device at 647 nm and using a smartphone camera, the camera could capture high-resolution images. These results conclusively indicate that with any modern smartphone camera, a small box lighted to 647 nm, and optical magnifier; a powerful and expensive laboratory scanning machine can be replaced by another that is inexpensive, portable and ready to use anywhere.
ContributorsMakimaa, Heyde (Author) / Holechek, Susan (Thesis director) / Stafford, Phillip (Committee member) / Jayasuriya, Suren (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Monoclonal antibody therapy focuses on engineering immune cells to target specific peptide sequences indicative of disease. An impediment in the continued advancement of this market is the lack of an efficient, inexpensive means of characterization that can be broadly applied to any antibody while still providing high-density data. Many characterization methods address an antibody's affinity for its cognate sequence but overlook other important aspects of binding behavior such as off-target binding interactions. The purpose of this study is to demonstrate how the binding intensity between an antibody and a library of random-sequence peptides, otherwise known as an immunosignature, can be evaluated to determine antibody specificity and polyreactivity. A total of 24 commercially available monoclonal antibodies were assayed on 125K and 330K peptide microarrays and analyzed using a motif clustering program to predict candidate epitopes within each antigen sequence. The results support the further development of immunosignaturing as an antibody characterization tool that is relevant to both therapeutic and non-therapeutic antibodies.
ContributorsDai, Jennifer T. (Author) / Stafford, Phillip (Thesis director) / Diehnelt, Chris (Committee member) / School of Life Sciences (Contributor) / W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Fruit flies show a strong attraction to fruit odors. Most fruit odors, including strawberry scent, are complex multimolecular mixtures comprised of many chemically distinct constituents. How animals are able to process these mixtures and derive behaviorally relevant information is largely unknown. A new procedure was created to test odor preference for Heisenberg canton-s strain of Drosophila melanogaster. 30 flies were cold anesthetized at 4.2°C for 30 minutes and then placed in a testing arena. After acclimating for 45 minutes, the flies were exposed to two sources of air, one with ripe strawberry odor and one with only humidified air. Images were captured every minute for an hour and a preference index was calculated for every 10th image. The Drosophila had a positive average preference for the strawberry odor. Five out of six trials showed a general increase in odor preference over the course of the trial. While there was a generally positive trend for average preference over time, there was not a significant increase in average odor preference from time 1 to time 60. The data indicates that Drosophila show a preference for strawberry odor over humidified air, and we propose to extend this test to investigate how Drosophila process and react to complex odors and their chemical constituents.
ContributorsSteinmetz, Kyle J (Author) / Smith, Brian (Thesis director) / Jernigan, Chris (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Recent data suggests that olfactory input is important for antennal lobe development in honey bees. Chronic association of a single odor to food resources during crucial stages of development results in delayed antennal lobe development for mature foraging bees. The antennal lobes of these bees instead closely resemble an immature network observed in young, newly emerged bees. Using an odor stimuli variance assay, learning and memory tests can be used to explore how well honey bees discriminate single odors within complex odor mixtures. Here we are validating two different odor mixtures, a Brassica rapa floral blend and a second replicate mixture composed of common molecularly dissimilar odors. Odors in each mixture are either held constant or varied in concentration over 16 conditioning trials. Subsequent memory tests are performed two hours later to observe the ability of bees to distinguish and recognize specific odor components in each mixture. So far in our assay we find high rates of generalization for both odor mixtures. In general, more bees responded to all odors in the replicate treatment group over the Brassica treatment group. Additionally, bees in the Brassica treatment group did not respond to the target odor. More data is being collected to validate this assay. In future studies, I propose to apply this behavioral assay to bees with an altered olfactory developmental in order to see the functional impacts of this chronic odor association treatment.
ContributorsHalby, Rachael (Author) / Smith, Brian (Thesis director) / Jernigan, Christopher (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Asperger's syndrome is a high-functioning subset of Autism Spectrum Disorders (ASD). Diagnosed patients often lack refined social skills but possess a normal level of cognitive skills without delay in language development. These deficient social skills can impact the ability to find and maintain a job, which can be burdensome for all individuals involved in the patient's life. Although the causes of this condition are largely unknown, a wide variety of social and cognitive therapies have been used to reduce symptom severity, one of which is Mindfulness-Based Stress Reduction (MBSR). Mindfulness is the act of being aware on purpose to whatever is being experienced in the present moment with non-judgment and receptivity. MBSR has been used to bring greater awareness to sensations, thoughts and emotions with the result being reduced reactivity and increased purposeful responsiveness. It is therefore the aim of this study to address the use of an 8-week Mindfulness-Based Stress Reduction in adolescents with clinical Asperger's Syndrome to reduce reactive tendencies. This study will utilize a randomized control group of waitlisted participants given MBSR informational material and a practicing MBSR group. Post-MBSR Parent Global Impressions-III (PGI-III) and Social Responsiveness Scale scores are hypothesized to be improved in MBSR group and unaffected in the control for behavioral markers with no change in core autistic symptoms. Daily average cortisol response is also expected to decrease in the experimental group with unaffected levels in the control.
ContributorsBrzezinski, Molly Alexandra (Author) / Smith, Brian (Thesis director) / Sebren, Ann (Committee member) / School of Music (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The mammalian olfactory system is commonly studied by using the mouse as a model system. Odor habituation is used to investigate odor perception and learning processes. Most previous experimental preparations have been tedious, requiring a researcher to manually change odorants, record investigation time and duration at each odorant, or physical alteration on the mice to enable video tracking. These limitations were overcame by creating an odorized hole-board to allow for systematic and automatic recording of olfactory behavior in mice. A cohort of five male mice were utilized in these experiments and the responses to the odor of strawberries, a diet staple of wile mice, were examined. Experiment 1 showed that free-feeding mice exhibit a preference to locations with strawberry (over control locations), even when these locations can only be identified using olfaction. This preference habituates within a trial but not across days. Experiment 2 showed that strawberry odor without reward causes habituation or extinction to the odor both within trials and across days. From these experiments, it can be concluded that mice innately explore strawberry odor and this can be exploited to the study odor habituation using an odorized hole-board.
ContributorsMa, Jason (Author) / Smith, Brian (Thesis director) / Gerkin, Richard (Committee member) / Oddo, Salvatore (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Animals must learn to ignore stimuli that are irrelevant to survival, a process referred to as latent inhibition. The Amtyr1 gene has been shown through quantitative trait loci mapping to be linked to strong latent inhibition in honey bees. Here we implicate this G-protein coupled receptor for the biogenic amine tyramine as an important factor underlying this form of learning in honey bees. We show that dsRNA targeted to disrupt the tyramine receptors, specifically affects latent inhibition but not excitatory associative conditioning. Our results therefore identify a distinct reinforcement pathway for latent inhibition in insects.
ContributorsPetersen, Mary Margaret (Author) / Smith, Brian (Thesis director) / Wang, Ying (Committee member) / Sinakevitch, Irina (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
In this project, biochemical characteristics of peptide binding agents, synthetic antibodies or synbodies, were examined with respect to the capture efficiency and specific binding ability to norovirus. Norovirus, although generally not a deadly pathogen, is the most common cause of acute gastroenteritis and outbreaks present a large social and financial burden to the healthcare and food service industries. With Dr. Diehnelt's laboratory group, a platform has been developed that enables us to rapidly construct peptide-based affinity ligands that can be characterized for binding to norovirus. The design needed to display clear results, be simple to operate, and be inexpensive to produce and use. Four synbodies, originally engineered with a specificity to the GII.4 Minerva genotype were tested with different virus strains varying in similarity to the GII.4 Minerva between 43% and 95.4%. Initial assays utilized norovirus-like particles to qualitatively compare the capture efficiency of the different synbodies without utilizing limited resources. To quantify the amount of actual virus captured by the synbodies, western blots with RT-PCR and RT-qPCR were utilized. The results indicated the synbodies were able to enrich the dilute solutions of the different noroviruses utilizing a magnetic bead pull-down assay. The capture efficiencies of the synbodies were comparable to currently utilized binding agents such as aptamers and porcine gastric mucine magnetic beads. This thesis presents data collected over nearly two years of research at the Center for Innovations in Medicine at the Biodesign Institute located at Arizona State University.
ContributorsSlosky, Rachael Marie (Author) / Diehnelt, Chris (Thesis director) / Stafford, Phillip (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
In Apis mellifera, gustatory responsiveness to sucrose is a good indicator of learning ability \u2014 in that individuals with high sucrose responsiveness will typically form faster, longer-lasting associations with conditioned stimulus than individuals with a low sucrose responsiveness. The purpose of this study was to determine whether experience with olfactory conditioning had lasting effects on gustatory responsiveness. Groups were placed in an environment that would facilitate association of an odor to a sucrose reward, tested for retention, then tested for gustatory responsiveness. Control groups underwent the same testing schedule, but were not exposed to odor in the first environment. There was no significant difference in gustatory responsiveness between the two groups. Mann-Whitney tests were used to analyze the results, and though the mean GRS score was lower among the treatment group there was no significant trend, possibly due to small sample sizes.
ContributorsSeemann, J. H. (Author) / Amdam, Gro (Thesis director) / Smith, Brian (Committee member) / Barrett, The Honors College (Contributor)
Created2016-05
Description
By increasing the mean and variance of environmental temperatures, climate change has caused local extinctions and range shifts of numerous species. However, biologists disagree on which populations and species are most vulnerable to future warming. This debate arises because biologists do not know which physiological processes are most vulnerable to temperature or how to model these processes in complex environments. Using the South American locust (Schistocerca cancellata) as a model system, my dissertation addressed this debate and explained how climate limits the persistence of locust populations. Locusts of S. cancellata are serious agricultural pests with occasional outbreaks covering up to 4 million km2 over six countries. Because outbreaks are largely driven by climate, understanding how climate limits the persistence of locusts may help predict crop losses in future climates. To achieve this aim, I integrated observational, experimental, and computational approaches. First, I tested a physiological model of heat stress. By measuring the heat tolerance of locusts under different oxygen concentrations, I demonstrated that heat tolerance depends on oxygen supply during the hatchling stage only. Second, I modeled the geographic distribution of locusts using physiological traits. I started by measuring thermal effects on consumption and defecation of field-captured locusts, and I then used these data to model energy gain in current and future climates. My results indicated that incorporating physiological mechanisms can improve the accuracy of models and alter predicted impacts of climate change. Finally, I explored the causes and consequences of intraspecific variation in heat tolerance. After measuring heat tolerance of locusts in different hydration states and developmental stages, I modeled survival in historical microclimates. My models indicated that recent climate change has amplified the risk of overheating for locusts, and this risk depended strongly on shade availability, hydration state, and developmental stage. Therefore, the survival of locusts in future climates will likely depend on their access to shade and water. Overall, my dissertation argues that modeling physiological mechanisms can improve the ability of biologists to predict the impacts of climate change.
ContributorsYoungblood, Jacob (Author) / Angilletta, Michael (Thesis advisor) / Buckley, Lauren (Committee member) / Cease, Arianne (Committee member) / Smith, Brian (Committee member) / Vanden Brooks, John (Committee member) / Arizona State University (Publisher)
Created2022