Matching Items (162)
Description
Is it possible to treat the mouth as a natural environment, and determine new methods to keep the microbiome in check? The need for biodiversity in health may suggest that every species carries out a specific function that is required to maintain equilibrium and homeostasis within the oral cavity. Furthermore, the relationship between the microbiome and its host is mutually beneficial because the host is providing microbes with an environment in which they can flourish and, in turn, keep their host healthy. Reviewing examples of larger scale environmental shifts could provide a window by which scientists can make hypotheses. Certain medications and healthcare treatments have been proven to cause xerostomia. This disorder is characterized by a dry mouth, and known to be associated with a change in the composition, and reduction, of saliva. Two case studies performed by Bardow et al, and Leal et al, tested and studied the relationships of certain medications and confirmed their side effects on the salivary glands [2,3]. Their results confirmed a relationship between specific medicines, and the correlating complaints of xerostomia. In addition, Vissink et al conducted case studies that helped to further identify how radiotherapy causes hyposalivation of the salivary glands [4]. Specifically patients that have been diagnosed with oral cancer, and are treated by radiotherapy, have been diagnosed with xerostomia. As stated prior, studies have shown that patients having an ecologically balanced and diverse microbiome tend to have healthier mouths. The oral cavity is like any biome, consisting of commensalism within itself and mutualism with its host. Due to the decreased salivary output, caused by xerostomia, increased parasitic bacteria build up within the oral cavity thus causing dental disease. Every human body contains a personalized microbiome that is essential to maintaining health but capable of eliciting disease. The Human Oral Microbiomics Database (HOMD) is a set of reference 16S rRNA gene sequences. These are then used to define individual human oral taxa. By conducting metagenomic experiments at the molecular and cellular level, scientists can identify and label micro species that inhabit the mouth during parasitic outbreaks or a shifting of the microbiome. Because the HOMD is incomplete, so is our ability to cure, or prevent, oral disease. The purpose of the thesis is to research what is known about xerostomia and its effects on the complex microbiome of the oral cavity. It is important that researchers determine whether this particular perspective is worth considering. In addition, the goal is to create novel experiments for treatment and prevention of dental diseases.
ContributorsHalcomb, Michael Jordan (Author) / Chen, Qiang (Thesis director) / Steele, Kelly (Committee member) / Barrett, The Honors College (Contributor) / College of Letters and Sciences (Contributor)
Created2015-05
Description
Testosterone (T) is a steroid hormone that affects behavior and reproductive traits (e.g. spermatogenesis and ornamentation) in vertebrates. In addition to long-term influences, T can rapidly increase in males following aggressive male-male encounters. Less is known how females directly influence male T and behavior, though research with humans suggests that sexually attractive females elicit a greater increase in male T and reproductive behavior than unattractive females. In birds, the influence of female attractiveness on male T and behavior is currently untested. We hypothesized that T and courtship behavior in male zebra finches would correlate with female attractiveness. We used red leg bands to make females "attractive" and green bands to make them "unattractive" (unbanded females were controls) as previous research suggests that zebra finches prefer red colors over green in mating contexts. We collected blood from males before and after "speed-dating" trials to measure changes in plasma T and analyzed male courtship behaviors from trial video recordings. The likelihood of plasma T increasing after a trial was significantly greater in males who were with red-banded females compared to control females, suggesting males may find them more attractive than green or control females. Additionally, independent of band color, males who exhibited greater T differences initiated courtship sooner and spent more time closest to females. However, courtship initiation and time spent near females were not correlated with band color. Overall, our results suggest that female attractiveness can influence male reproductive physiology, but the presence of a female may trigger male courtship behavior.
ContributorsBero-Buell, Brianna Danielle (Author) / McGraw, Kevin (Thesis director) / Deviche, Pierre (Committee member) / Ligon, Russell (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
The objectives of this review include a discussion of the West Nile Virus phylogeny, transmission history, how the virus functions in the body and how it is a threat to public health, and then discusses these items related to vaccine technology surrounding West Nile Virus. This will include past developments, current research in the field and what it may take to develop such a vaccine safe and economical for human usage.
ContributorsSlinker, Haleigh Renee (Author) / Chen, Qiang (Thesis director) / Huffman, Holly (Committee member) / Oberstein, Bruce (Committee member) / Barrett, The Honors College (Contributor) / School of Letters and Sciences (Contributor)
Created2013-05
Description
Historically, the study of cognition has focused on species-specific learning, memory, problem-solving and decision-making capabilities, and emphasis was placed on the few high-performing individuals who successfully completed cognitive tasks. Studies often deemed the success of a small fraction of individuals as suggestive of the cognitive capacity of the entire species. Recently though, interest in individual variation in cognitive ability within species has increased. This interest has emerged concomitantly with studies of variation in animal personalities (i.e. behavioral syndromes). Cognitive ability may be closely tied to personality because the mechanisms by which an individual perceives and uses environmental input (cognition) should influence how that individual consistently responds to various ecological demands (personality). However, empirical support for links between animal cognition and behavioral syndromes is currently lacking. I examined individual variation in cognition and personality in male veiled chameleons, Chamaeleo calyptratus. I considered three axes of personality (aggression, activity, and exploratory behavior) and cognition in a foraging context using visual cues − specifically, the ability to associate a color with a food reward. I found that aggression was positively correlated with the proportion of correct choices and number of consecutive correct choices. Also, one measure of exploration (the number of vines touched in a novel environment) was correlated negatively with the proportion of correct choices and positively with the number of consecutive incorrect decisions. My investigation suggests that more aggressive, less exploratory chameleons were more successful learners, and that there exists a shared pathway between these personality traits and cognitive ability.
ContributorsBruemmer, Sarah Adele (Author) / McGraw, Kevin (Thesis director) / Rutowski, Ronald (Committee member) / Ligon, Russell (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
Dental caries also known as tooth decay is a bacterial infection that causes demineralization and destruction of enamel dentin and cementum in the tooth. This bacterium, Streprococcus mutans, feeds on the carbohydrates in the mouth and produces lactic acids that result in dental caries. This thesis discusses the use of plants to produce antibodies, Guy 13 and anti-GTFB to treat this dental disease. We believe these plant-derived antibodies will be effective to treat dental caries and economical to produce.
ContributorsSayegh, Luvenia Crystal (Author) / Chen, Qiang (Thesis director) / Garg, Vikas (Committee member) / Barrett, The Honors College (Contributor) / School of Letters and Sciences (Contributor)
Created2014-12
Description
Urbanization exposes wildlife to many unfamiliar environmental conditions, including the presence of novel structures and food sources. Adapting to or thriving within such anthropogenic modifications may involve cognitive skills, whereby animals come to solve novel problems while navigating, foraging, etc. The increased presence of humans in urban areas is an additional environmental challenge that may potentially impact cognitive performance in wildlife. To date, there has been little experimental investigation into how human disturbance affects problem solving in animals from urban and rural areas. Urban animals may show superior cognitive performance in the face of human disturbance, due to familiarity with benign human presence, or rural animals may show greater cognitive performance in response to the heightened stress of unfamiliar human presence. Here, I studied the relationship between human disturbance, urbanization, and the ability to solve a novel foraging problem in wild-caught juvenile house finches (Haemorhous mexicanus). This songbird is a successful urban dweller and native to the deserts of the southwestern United States. In captivity, finches captured from both urban and rural populations were presented with a novel foraging task (sliding a lid covering their typical food dish) and then exposed to regular periods of high or low human disturbance over several weeks before they were again presented with the task. I found that rural birds exposed to frequent human disturbance showed reduced task performance compared to human-disturbed urban finches. This result is consistent with the hypothesis that acclimation to human presence protects urban birds from reduced cognition, unlike rural birds. Some behaviors related to solving the problem (e.g. pecking at and eying the dish) also differed between urban and rural finches, possibly indicating that urban birds were less neophobic and more exploratory than rural ones. However, these results were unclear. Overall, these findings suggest that urbanization and acclimation to human presence can strongly predict avian response to novelty and cognitive challenges.
ContributorsCook, Meghan Olivia (Author) / McGraw, Kevin (Thesis director) / Bimonte-Nelson, Heather (Committee member) / Weaver, Melinda (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Ebola hemorrhagic fever (EHF) is a severe and often fatal disease in human and nonhuman primates, caused by the Ebola virus. Approximately 30 years after the first epidemic, there is no vaccine or therapeutic medication approved to counter the Ebola virus. In this dissertation, a geminiviral replicon system was used to produce Ebola immune complex (EIC) in plant leaves and tested it as an Ebola vaccine. The EIC was produced in Nicotiana benthamiana leaves by fusing Ebola virus glycoprotein (GP1) to the C-terminus of heavy chain of 6D8 monoclonal antibody (mAb), which is specific to the 6D8 epitope of GP1, and co-expressing the fusion with the light chain of 6D8 mAb. EIC was purified by ammonium sulfate precipitation and protein A or protein G affinity chromatography. EIC was shown to be immunogenic in mice, but the level of antibody against Ebola virus was not sufficient to protect the mice from lethal the Ebola challenge. Hence, different adjuvants were tested in order to improve the immunogenicity of the EIC. Among several adjuvants that we used, Poly(I:C), which is a synthetic analog of double-stranded ribonucleic acid that can interact with a Toll-like receptor 3, strongly increased the efficacy of our Ebola vaccine. The mice immunized with EIC co-administered with Poly(I:C) produced high levels of neutralizing anti-Ebola IgG, and 80% of the mice were protected from the lethal Ebola virus challenge. Moreover, the EIC induced a predominant T-helper type 1 (Th1) response, whereas Poly(I:C) co-delivered with the EIC stimulated a mixed Th1/Th2 response. This result suggests that the protection against lethal Ebola challenge requires both Th1 and Th2 responses. In conclusion, this study demonstrated that the plant-produced EIC co-delivered with Poly(I:C) induced strong and protective immune responses to the Ebola virus in mice. These results support plant-produced EIC as a good vaccine candidate against the Ebola virus. It should be pursued further in primate studies, and eventually in clinical trials.
ContributorsPhoolcharoen, Waranyoo (Author) / Mason, Hugh S (Thesis advisor) / Chen, Qiang (Thesis advisor) / Arntzen, Charles J. (Committee member) / Change, Yung (Committee member) / Ma, Julian (Committee member) / Arizona State University (Publisher)
Created2010
Description
Rock Doves (Columba livia), also known as pigeons, are a common sight to city dwellers around the world. Often overlooked as urban pests, these birds have intriguing iridescent coloration on their necks that has been the subject of few studies. Previous studies have documented the multimodal reflectance spectra of the iridescence and the keratin cortex microstructures responsible for those properties, but do not address questions about the biological context of this coloration. In this study, I explore the factors that affect how this directional signal might appear to intended receivers (assumed to be females). Pigeon neck feathers were obtained from captive-raised birds and measured for reflectance values at numerous angles in the hemisphere above the feather to obtain a directional reflectance distribution. Each feather was mounted individually, and measurements were taken at a consistent location on the feather using a spectrophotometer; the collector was positioned directly above the feather, while we moved the light source in both azimuth and elevation on a Carden arm to simulate changes in pigeon movements during courtship. Depending on the elevation and azimuth of the light source, pigeon neck feathers shift in appearance from green to purple, with an accompanying shift in the location and intensity of reflectance peaks. Additionally, this unique coloration is due to multiple reflectance peaks in the avian vision field between 300 and 700nm. These data coupled with qualitative behavioral observations of Rock Dove courtship inform our understanding of how the color signal is displayed and how it appears to a potential mate; as a female observes the movements in a male courtship display, properties of the iridescence utilize multiple viewing angles to create a dynamic color array.
ContributorsFankhauser, Kaci Lynn (Author) / Rutowski, Ronald (Thesis director) / McGraw, Kevin (Committee member) / McBeath, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Coronavirus disease 2019 (COVID-19), an illness caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), has been responsible for significant social and economic
disruption, prompting an urgent search for therapeutic solutions. The spike protein of the virus
has been examined as an immunogenic target because of its role in viral binding and fusion
necessary for infection of host cells. Previous studies have identified a recombinant protein
(denoted as S1) that has been shown to potentially induce a neutralizing antibody response by
mimicking the structure of the SARS-CoV-2 spike protein. We have produced the S1 in plants
using agroinfiltration, a plant transformation technique whereby plasmid-containing
Agrobacterium tumefaciens is injected into Nicotiana benthamiana plants, resulting in transfer of
the desired gene from bacteria to plant cells. S1 was expressed to high levels within 5 days of
infiltration, and Western blot analysis showed recognition of the S1 by an anti-S1 antibody.
ELISA results exhibited increased binding activity to anti-S1 with increasing concentrations of
S1, indicating their specific interaction. This ongoing study will demonstrate the potential of a
plant-produced S1 as a vaccine, therapeutic, and diagnostic tool against COVID-19 that is not
only effective, but also cost-efficient and scalable in comparison to conventional mammalian cell
culture production methods.
coronavirus 2 (SARS-CoV-2), has been responsible for significant social and economic
disruption, prompting an urgent search for therapeutic solutions. The spike protein of the virus
has been examined as an immunogenic target because of its role in viral binding and fusion
necessary for infection of host cells. Previous studies have identified a recombinant protein
(denoted as S1) that has been shown to potentially induce a neutralizing antibody response by
mimicking the structure of the SARS-CoV-2 spike protein. We have produced the S1 in plants
using agroinfiltration, a plant transformation technique whereby plasmid-containing
Agrobacterium tumefaciens is injected into Nicotiana benthamiana plants, resulting in transfer of
the desired gene from bacteria to plant cells. S1 was expressed to high levels within 5 days of
infiltration, and Western blot analysis showed recognition of the S1 by an anti-S1 antibody.
ELISA results exhibited increased binding activity to anti-S1 with increasing concentrations of
S1, indicating their specific interaction. This ongoing study will demonstrate the potential of a
plant-produced S1 as a vaccine, therapeutic, and diagnostic tool against COVID-19 that is not
only effective, but also cost-efficient and scalable in comparison to conventional mammalian cell
culture production methods.
ContributorsNguyen, Katherine (Author) / Chen, Qiang (Thesis director) / Ghirlanda, Giovanna (Committee member) / Jugler, Collin (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
X-ray free-electron lasers provide novel opportunities to conduct single particle analysis on nanoscale particles. Coherent diffractive imaging experiments were performed at the Linac Coherent Light Source (LCLS), SLAC National Laboratory, exposing single inorganic core-shell nanoparticles to femtosecond hard-X-ray pulses. Each facetted nanoparticle consisted of a crystalline gold core and a differently shaped palladium shell. Scattered intensities were observed up to about 7 nm resolution. Analysis of the scattering patterns revealed the size distribution of the samples, which is consistent with that obtained from direct real-space imaging by electron microscopy. Scattering patterns resulting from single particles were selected and compiled into a dataset which can be valuable for algorithm developments in single particle scattering research.
ContributorsLi, Xuanxuan (Author) / Chiu, Chun-Ya (Author) / Wang, Hsiang-Ju (Author) / Kassemeyer, Stephan (Author) / Botha, Sabine (Author) / Shoeman, Robert L. (Author) / Lawrence, Robert (Author) / Kupitz, Christopher (Author) / Kirian, Richard (Author) / James, Daniel (Author) / Wang, Dingjie (Author) / Nelson, Garrett (Author) / Messerschmidt, Marc (Author) / Boutet, Sebastien (Author) / Williams, Garth J. (Author) / Hartman, Elisabeth (Author) / Jafarpour, Aliakbar (Author) / Foucar, Lutz M. (Author) / Barty, Anton (Author) / Chapman, Henry (Author) / Liang, Mengning (Author) / Menzel, Andreas (Author) / Wang, Fenglin (Author) / Basu, Shibom (Author) / Fromme, Raimund (Author) / Doak, R. Bruce (Author) / Fromme, Petra (Author) / Weierstall, Uwe (Author) / Huang, Michael H. (Author) / Spence, John (Author) / Schlichting, Ilme (Author) / Hogue, Brenda (Author) / Liu, Haiguang (Author) / ASU Biodesign Center Immunotherapy, Vaccines and Virotherapy (Contributor) / Biodesign Institute (Contributor) / Applied Structural Discovery (Contributor) / College of Liberal Arts and Sciences (Contributor) / School of Molecular Sciences (Contributor) / Department of Physics (Contributor) / School of Life Sciences (Contributor)
Created2017-04-11