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- Creators: Dean, W.P. Carey School of Business
- Creators: Gile, Gillian
- Creators: Bond, Angela
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Description
Hundreds of thousands of people die annually from malaria; a protozoan of the genus Plasmodium is responsible for this mortality. The Plasmodium parasite undergoes several life stages within the mosquito vector, the transition between which require passage across the lumen of the mosquito midgut. It has been observed that in about 15% of parasites that develop ookinetes in the mosquito abdomen, sporozoites never develop in the salivary glands, indicating that passage across the midgut lumen is a significant barrier in parasite development (Gamage-Mendis et al., 1993). We aim to investigate a possible correlation between passage through the midgut lumen and drug-resistance trends in Plasmodium falciparum parasites. This study contains a total of 1024 Anopheles mosquitoes: 187 Anopheles gambiae and 837 Anopheles funestus samples collected in high malaria transmission areas of Mozambique between March and June of 2016. Sanger sequencing will be used to determine the prevalence of known resistance alleles for anti-malarial drugs: chloroquine resistance transporter (pfcrt), multidrug resistance (pfmdr1) gene, dihydropteroate synthase (pfdhps) and dihydrofolate reductase (pfdhfr). We compare prevalence of resistance between abdomen and head/thorax in order to determine whether drug resistant parasites are disproportionately hindered during their passage through the midgut lumen. A statistically significant difference between resistance alleles in the two studied body sections supports the efficacy of new anti-malarial gene surveillance strategies in areas of high malaria transmission.
ContributorsPhillips, Keeley Isabella (Author) / Huijben, Silvie (Thesis director) / Gile, Gillian (Committee member) / Young, Steven (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The non-native mosquito Aedes aegypti has become a common nuisance in Maricopa county. Associated with human settlement, Ae. aegypti is known to reproduce in standing water sources both indoors and outdoors, within vessels such as tires, flowerpots, and neglected swimming pools (Jansen & Beebe, 2010). Ae. aegypti and the related Ae. albopictus are the primary vectors of the arboviral diseases chikungunya, Zika, yellow fever and dengue. Ae. aegypti tends to blood feed multiple times per gonotrophic cycle (cycle of feeding and egg laying) which, alongside a preference for human blood and close association with human habitation, contributes to an increased risk of Ae. aegypti borne virus transmission (Scott & Takken, 2012). Between 2010-2017, 153 travel-associated cases of dengue were reported in the whole of Arizona (Rivera et al., 2020); while there have been no documented locally transmitted cases of Aedes borne diseases in Maricopa county, there are no apparent reasons why local transmission can’t occur in the future via local Aedes aegypti mosquitoes infected after feeding from travelling viremic hosts. Incidents of local dengue transmission in New York (Rivera et al., 2020) and Barcelona (European Center for Disease Control [ECDC], 2019) suggest that outbreaks of Aedes borne arbovirus’ can occur in regions more temperate than the current endemic range of Aedes borne diseases. Further, while the fact that Ae. aegypti eggs have a high mortality rate when exposed to cold temperatures limits the ability for Ae aegypti to establish stable breeding populations in temperate climates (Thomas, Obermayr, Fischer, Kreyling, & Beierkuhnlein, 2012), global increases in temperature will expand the possible ranges of Ae aegypti and Aedes borne diseases.
ContributorsHon, Ruiheng (Author) / Paaijmans, Krijn (Thesis director) / Bond, Angela (Committee member) / Angilletta, Michael (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The 18S ribosomal RNA gene is ubiquitous across eukaryotes as it encodes the RNA component of the ribosomal small subunit. It is the most commonly used marker in molecular studies of unicellular eukaryotes (protists) due to its species specificity and high copy number in the protist genome. Recent studies have revealed the widespread occurrence of intragenomic (intra-individual) polymorphism in many protists, an understudied phenomenon which contradicts the assumed homogeneity of the 18S throughout an individual genome. This thesis quantifies and analyzes the level of intragenomic and intraspecific 18S sequence variability in three Trichonympha species (T. campanula, T. collaris, T. postcylindrica) from Zootermopsis termites. Single-cell DNA extractions, PCR, cloning, and sequencing were performed to obtain 18S rRNA sequence reads, which were then analyzed to determine levels of sequence divergence among individuals and among species. Intragenomic variability was encountered in all three species. However, excluding singleton mutations, sequence divergence was less than 1% in 53 of the 56 compared individuals. T. collaris exhibited the most substantial intragenomic variability, with sequence divergence ranging from 0 to 3.4%. Further studies with more clones per cell are needed to elucidate the true extent of intragenomic variability in Trichonympha.
ContributorsBobbett, Bradley (Author) / Gile, Gillian (Thesis director) / Liebig, Juergen (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis aimed to develop a consistent protocol used to effectively image the apolipoprotein E (ApoE) ε4 allele, which is a known genetic risk factor for Alzheimer’s Disease (AD). The research team used methods to extract DNA from saliva samples, amplify the DNA using polymerase chain reaction (PCR), and image the results using gel electrophoresis and a transilluminator. Extensive literature review was used to optimize these techniques. Future studies will use these methods of characterizing the ApoE ε4 allele as preliminary work towards the goal of integrating this protocol into ongoing research in aging within the Motor Rehabilitation and Learning (MRL) Lab on Arizona State University’s campus.
ContributorsWorman, Drew (Author) / Schaefer, Sydney (Thesis director) / Lewis, Candace (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Since its inception in the early 1990s, the concept of gene vaccines, particularly DNA vaccines, has enticed researchers across the board due to its simple design, flexible modification, and overall inexpensive cost of manufacturing. However, the past three decades have proven to be less fruitful than anticipated as scientists have yet to tackle the issue of inducing a strong enough response in humans and non-human primates to protect against foreign pathogens, an issue that has since been coined as the “simian barrier.” This appears to be a human/primate barrier as protective vaccines have been produced for other mammals. Despite millions of dollars in research along with some of the world’s brightest minds chipping in to resolve this, there has yet to be any truly viable solution to overcoming this barrier. With current research illustrating effective applications of RNA vaccines in humans, these studies may be uncovering the solution to the largely unsolved simian barrier dilemma. If vaccines using RNA, the transcribed version of DNA, are effective in humans, the problem may be inefficient transcription of the DNA. This may be attributable to a DNA promoter that has insufficient activity in primates. Additionally, with DNA vaccines being even cheaper and easier to manufacture than RNA vaccines, along with having no required cold chain for distribution, this concept remains more promising than RNA vaccines that are further along in clinical trials.
ContributorsWillis, Joshua Aaron (Author) / Johnston, Stephen (Thesis director) / Sykes, Kathryn (Committee member) / Shen, Luhui (Committee member) / Dean, W.P. Carey School of Business (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12