Matching Items (79)
Description
The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in a single fly that would allow for simultaneous expression of the oncogene and, in <br/>the surrounding cells, other genes of interest. This system would help establish Drosophila as a <br/>more versatile and reliable model organism for cancer research. Furthermore, pilot studies were <br/>performed, using elements of the final proposed system, to determine if tumor growth is possible <br/>in the center of the disc, which oncogene produces the best results, and if oncogene expression <br/>induced later in development causes tumor growth. Three different candidate genes were <br/>investigated: RasV12, PvrACT, and Avli.
ContributorsSt Peter, John Daniel (Author) / Harris, Rob (Thesis director) / Varsani, Arvind (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Clean water for drinking, food preparation, and bathing is essential for astronaut health and safety during long duration habitation of the International Space Station (ISS), including future missions to Mars. Despite stringent water treatment and recycling efforts on the ISS, it is impossible to completely prevent microbial contamination of onboard water supplies. In this work, we used a spaceflight analogue culture system to better understand how the microgravity environment can influence the pathogenesis-related characteristics of Burkholderia cepacia complex (Bcc), an opportunistic pathogen previously recovered from the ISS water system. The results of the present study suggest that there may be important differences in how this pathogen can respond and adapt to spaceflight and other low fluid shear environments encountered during their natural life cycles. Future studies are aimed at understanding the underlying mechanisms responsible for these phenotypes.
ContributorsKang, Bianca Younseon (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, Mark (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Members of the Delphinidae family are widely distributed across the world’s oceans. We used a viral metagenomic approach to identify viruses in orca (Orcinus orca) and short-finned pilot whale (Globicephala macrorhynchus) muscle, kidney, and liver samples from deceased animals. From orca tissue samples (muscle, kidney, and liver), we identified a novel polyomavirus (Polyomaviridae), three cressdnaviruses, and two genomoviruses (Genomoviridae). In the short-finned pilot whale we were able to identify one genomovirus in a kidney sample. The presence of unclassified cressdnavirus within two samples (muscle and kidney) of the same animal supports the possibility these viruses might be widespread within the animal. The orca polyomavirus identified here is the first of its species and is not closely related to the only other dolphin polyomavirus previously discovered. The identification and verification of these viruses expands the current knowledge of viruses that are associated with the Delphinidae family.
ContributorsSmith, Kendal Ryan (Author) / Varsani, Arvind (Thesis director) / Kraberger, Simona (Committee member) / Dolby, Greer (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Phage therapy has been around for more than a century, but has regained interest in the field of medicine and holds significant potential to act as a treatment against a deadly bacterial infection in various cactus species. It was discovered that bacteriophages isolated from soil samples of potato plants were able to suppress Pectobacterium carotovorum, ‘Pectobacterium’ being within the family Pectobacteriaceae which contains the ‘Erwinia’ genus that causes soft rot diseases in various plants (Jones, 2012). The two scientists had co-inoculated “... the phage with the phytobacterium” (Jones, 2012) in order to suppress the growth and prevent the infection from occurring.
ContributorsFry, Danielle Elizabeth (Author) / Geiler-Samerotte, Kerry (Thesis director) / Pfeifer, Susanne (Committee member) / Varsani, Arvind (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Honey bee workers display remarkable flexibility in the aging process. This plasticity is closely tied to behavioral maturation. Workers who initiate foraging behavior at earlier ages have shorter lifespans, and much of the variation in total lifespan can be explained by differences in pre-foraging lifespan. Vitellogenin (Vg), a yolk precursor protein, influences worker lifespan both as a regulator of behavioral maturation and through anti-oxidant and immune functions. Experimental reduction of Vg mRNA, and thus Vg protein levels, in wild-type bees results in precocious foraging behavior, decreased lifespan, and increased susceptibility to oxidative damage. We sought to separate the effects of Vg on lifespan due to behavioral maturation from those due to immune and antioxidant function using two selected strains of honey bees that differ in their phenotypic responsiveness to Vg gene knockdown. Surprisingly, we found that lifespans lengthen in the strain described as behaviorally and hormonally insensitive to Vg reduction. We then performed targeted gene expression analyses on genes hypothesized to mediate aging and lifespan: the insulin-like peptides (Ilp1 and 2) and manganese superoxide dismutase (mnSOD). The two honey bee Ilps are the most upstream components in the insulin-signaling pathway, which influences lifespan in Drosophila melanogaster and other organisms, while manganese superoxide dismutase encodes an enzyme with antioxidant functions in animals. We found expression differences in the llps in fat body related to behavior (llp1 and 2) and genetic background (Ilp2), but did not find strain by treatment effects. Expression of mnSOD was also affected by behavior and genetic background. Additionally, we observed a differential response to Vg knockdown in fat body expression of mnSOD, suggesting that antioxidant pathways may partially explain the strain-specific lifespan responses to Vg knockdown.
ContributorsIhle, Kate (Author) / Fondrk, M. Kim (Author) / Page, Robert (Author) / Amdam, Gro (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-01-01
Description
Following the journey through the sewerage system, wastewater is subject to a series of purification procedures, prior to water reuse and disposal of the resultant sewage sludge. Biosolids, also known as treated sewage sludge, deemed fit for application on land, is a nutrient-rich, semisolid byproduct of biological wastewater treatment. Technological progression in metagenomics has allowed for large-scale analysis of complex viral communities in a number of samples, including wastewater. Members of the Microviridae family are non-enveloped, ssDNA bacteriophages, and are known to infect enterobacteria. Members of the Genomoviridae family similarly are non-enveloped, ssDNA viruses, but are presumed to infect fungi rather than eubacteria. As these two families of viruses are not relatively documented and their diversity poorly classified, this study aimed to analyze the presence of genomoviruses and the diversity of microviruses in nine samples representative of wastewater in Arizona and other regions of the United States. Using a metagenomic approach, the nucleic acids of genomoviruses and microviruses were isolated, assembled into complete genomes, and characterized through visual analysis: a heat chart showing percent coverage for genomoviruses and a circular phylogenetic tree showing diversity of microviruses. The heat map results for the genomoviruses showed a large presence of 99 novel sequences in all nine wastewater samples. Additionally, the 535 novel microviruses displayed great diversity in the cladogram, both in terms of sub-family and isolation source. Further research should be conducted in order to classify the taxonomy of microviruses and the diversity of genomoviruses. Finally, this study suggests future exploration of the viral host, prior to entering the wastewater system.
ContributorsSchreck, Joshua Reuben (Author) / Varsani, Arvind (Thesis director) / Rolf, Halden (Committee member) / Misra, Rajeev (Committee member) / School of Film, Dance and Theatre (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The brain is considered the crux of identity, yet human behavior may be influenced by bacteria in gut microbiomes. Honeybees can exchange bacteria through their many social behaviors, making their microbiomes, and the effect they have on honeybee behavior, of interest. There is recent evidence suggesting the presence of bacteria existing in human brains, which can be investigated in honeybee brains due to their well-documented structure. The purpose of this study is to establish if lipopolysaccharide—a molecule on bacteria membranes—is present in the honeybee brain and if it colocalizes with vitellogenin—an immune mediator. Additionally, this study also seeks to establish the efficacy of embedding tissue samples in resin and performing immunohistochemistry for vitellogenin and lipopolysaccharide on sections.
ContributorsStrange, Amalie Sofie (Co-author) / Strange, Amalie (Co-author) / Amdam, Gro (Thesis director) / Baluch, Page (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Yellow-bellied marmots (Marmota flavivent) are semi-fossorial ground-dwelling sciurid rodents native to the western United States. They are facultatively social and live in colonies that may contain over 50 individuals. Marmot populations are well studied in terms of their diet, life cycle, distribution, and behavior, however, knowledge about viruses associated with marmots is very limited. In this study we aim to identify DNA viruses by non-invasive sampling of their feces. Viral DNA was extracted from fecal material of 35 individual marmots collected in Colorado and subsequently submitted to rolling circle amplification for circular molecule enrichment. Using a viral metagenomics approach which included high-throughput sequencing and verification of viral genomes using PCR, cloning and sequencing, a diverse group of single-stranded (ss) DNA viruses were identified. Diverse ssDNA viruses were identified that belong to two established families, Genomoviridae (n=7) and Anelloviridae (n=1) and several others that belong to unclassified circular replication associated encoding single-stranded (CRESS) DNA virus groups (n=19). There were also circular DNA molecules extracted (n=4) that appear to encode one viral-like gene and are composed of <1545 nt. The viruses that belonged to the family Genomoviridae clustered with those in the Gemycircularvirus genus. The genomoviruses were extracted from 6 samples. These clustered with gemycircularvirus extracted from arachnids and feces. The anellovirus, extracted from one sample, identified here has a genome sequence that is most similar to those from other rodent species, lagomorphs, and mosquitos. The CRESS viruses identified here were extracted from 9 samples and are novel and cluster with others identified from avian species. This study gives a snapshot of viruses associated with marmots based on fecal sampling.
ContributorsKhalifeh, Anthony (Author) / Varsani, Arvind (Thesis director) / Kraberger, Simona (Committee member) / Dolby, Greer (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Spaceflight and spaceflight analogue culture enhance the virulence and pathogenesis-related stress resistance of the foodborne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium). This is an alarming finding as it suggests that astronauts may have an increased risk of infection during spaceflight. This risk is further exacerbated as multiple studies indicate that spaceflight negatively impacts aspects of the immune system. In order to ensure astronaut safety during long term missions, it is important to study the phenotypic effects of the microgravity environment on a range of medically important microbial pathogens that might be encountered by the crew. This ground-based study uses the NASA-engineered Rotating Wall Vessel (RWV) bioreactor as a spaceflight analogue culture system to grow bacteria under low fluid shear forces relative to those encountered in microgravity, and interestingly, in the intestinal tract during infection. The culture environment in the RWV is commonly referred to as low shear modeled microgravity (LSMMG). In this study, we characterized the stationary phase stress response of the enteric pathogen, Salmonella enterica serovar Enteritidis (S. Enteritidis), to LSMMG culture. We showed that LSMMG enhanced the resistance of stationary phase cultures of S. Enteritidis to acid and thermal stressors, which differed from the LSSMG stationary phase response of the closely related pathovar, S. Typhimurium. Interestingly, LSMMG increased the ability of both S. Enteritidis and S. Typhimurium to adhere to, invade into, and survive within an in vitro 3-D intestinal co-culture model containing immune cells. Our results indicate that LSMMG regulates pathogenesis-related characteristics of S. Enteritidis in ways that may present an increased health risk to astronauts during spaceflight missions.
ContributorsKoroli, Sara (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, C. Mark (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
To date, there have been few, if any, studies evaluating the venom toxin levels in dogs that have been naturally envenomated by pit vipers. Understanding venom toxin pharmacokinetics in a clinical setting is important for a variety of reasons, including the potential to better elucidate treatment options, prognosis, and other factors associated with pit viper envenomation. In addition, dogs serve as a comparative species to humans for evaluating pit viper envenomations. This pilot study’s primary objective was to address the question of “What do we see?” in dogs presenting for rattlesnake envenomation. To answer this question, we obtained serum from envenomated dogs presenting at three veterinary clinics, then used enzyme-linked immunosorbent assay (ELISA) and western blot analysis to measure total venom and key toxins in sera. Phospholipase A2, a primary venom toxin, was identified in a few samples by the western blot, and contributed to the positive correlation between percent echinocytes in the blood and venom concentration. Medical data records were compared to venom concentrations measured using ELISA to determine whether there were any significant correlations. First, the hematological results were compared. Clotting times showed a strong positive correlation, clotting times and platelets showed a negative correlation, while echinocytes and platelets showed no correlation. When compared to venom concentration, clotting times showed a negative correlation, while age showed a positive correlation. Weight and platelets were also compared to venom concentration, but no significant correlations were found. The logistics of this study provided a real-world model where time elapsed between envenomation and hospital admission, thus giving a realistic look at what occurs in both animal and human medicine.
ContributorsNelson, Alexis (Co-author, Co-author) / DeNardo, Dale (Thesis director) / Woods, Craig (Thesis director) / Varsani, Arvind (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05