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Life Sciences Commons

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2019

University of Colorado, Boulder

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Articles 1 - 30 of 49

Full-Text Articles in Life Sciences

Wildfire Activity And Land Use Drove 20th‐Century Changes In Forest Cover In The Colorado Front Range, Kyle Rodman, Thomas T. Veblen, Sara Saraceni, Teresa B. Chapman Feb 2019

Wildfire Activity And Land Use Drove 20th‐Century Changes In Forest Cover In The Colorado Front Range, Kyle Rodman, Thomas T. Veblen, Sara Saraceni, Teresa B. Chapman

Geography Graduate Contributions

Recent shifts in global forest area highlight the importance of understanding the causes and consequences of forest change. To examine the influence of several potential drivers of forest cover change, we used supervised classifications of historical (1938–1940) and contemporary (2015) aerial imagery covering a 2932‐km2study area in the northern Front Range (NFR) of Colorado and we linked observed changes in forest cover with abiotic factors, land use, and fire history. Forest cover in the NFR demonstrated broad‐scale changes 1938–2015 and overall cover increased 7.8%, but there was notable spatial variability and many sites also experienced ...


Comparison Of Microbial Communities In The Sediments And Water Columns Of Frozen Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Pacifica Sommers, John Lawrence Darcy, Dorota L. Porazinska, Eli M.S. Gendron, Andrew G. Fountain, Felix Zamora, Kim Vincent, Kaelin M. Cawley, Adam J. Solon, Lara Vimercati, Jenna Ryder, Steven K. Schmidt Feb 2019

Comparison Of Microbial Communities In The Sediments And Water Columns Of Frozen Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Pacifica Sommers, John Lawrence Darcy, Dorota L. Porazinska, Eli M.S. Gendron, Andrew G. Fountain, Felix Zamora, Kim Vincent, Kaelin M. Cawley, Adam J. Solon, Lara Vimercati, Jenna Ryder, Steven K. Schmidt

University Libraries Open Access Fund Supported Publications

Although cryoconite holes, sediment-filled melt holes on glacier surfaces, appear small and homogenous, their microbial inhabitants may be spatially partitioned. This partitioning could be particularly important for maintaining biodiversity in holes that remain isolated for many years, such as in Antarctica. We hypothesized that cryoconite holes with greater species richness and biomass should exhibit greater partitioning between the sediments and water, promoting greater biodiversity through spatial niche partitioning. We tested this hypothesis by sampling frozen cryoconite holes along a gradient of biomass and biodiversity in the Taylor Valley, Antarctica, where ice-lidded cryoconite holes are a ubiquitous feature of glaciers. We ...


Identifying Neuronal Populations Underlying Social Buffering, Kylia Ahuna Jan 2019

Identifying Neuronal Populations Underlying Social Buffering, Kylia Ahuna

Undergraduate Honors Theses

Social interactions are vital to human health, in part, due to social buffering. Social buffering is the phenomenon by which fear and anxiety are reduced by the presence of an affiliative conspecific. While studies have demonstrated the behavioral effects of social buffering, there is less known about how these effects are mediated within the brain. There is evidence that the infralimbic cortex (IL) cortex is important in processing social information, and previous work in the Donaldson lab has demonstrated that optogenetic reactivation of cells previously active during novel social interaction (socially-labeled cells) in the IL was sufficient to decrease fear ...


Effects Of Changing Prosthetic Foot Stiffness On 3d Hip Angles In Toddlers With Versus Without Unilateral Transtibial Amputations, Kaitlyn Jayne, Kara Ashcraft, Alena M Grabowski Jan 2019

Effects Of Changing Prosthetic Foot Stiffness On 3d Hip Angles In Toddlers With Versus Without Unilateral Transtibial Amputations, Kaitlyn Jayne, Kara Ashcraft, Alena M Grabowski

Undergraduate Honors Theses

Background: Pediatric prosthetists and physical therapists have observed that use of prosthetic feet with different stiffnesses affects external hip rotation during walking in toddlers with unilateral transtibial amputations (TTAs). A protocol for prescribing pediatric prosthetic feet is needed to minimize injury from improper biomechanics.

Methods: 12 toddlers participated in this study (9 non-amputee, 3 with a TTA). Three custom passive prosthetic feet were made for each toddler with a TTA. Kinetic and kinematic data was at 0.50 m/s. Peak hip joint angles and range of motion were determined in the sagittal, frontal, and transverse planes.

Results: The data ...


Examination Of Time-Of-Day Differences In Fear-Related Memory Behavior In Male And Female Rats, Nicholas Brennan Jan 2019

Examination Of Time-Of-Day Differences In Fear-Related Memory Behavior In Male And Female Rats, Nicholas Brennan

Undergraduate Honors Theses

Post-traumatic stress disorder (PTSD) and other anxiety disorders are often characterized by impairment of the circadian system. Fear extinction learning is known to be modulated by the circadian system, but it is unclear if the time of extinction training or the time of extinction testing determines fluctuations in behavioral responses, or if these modulations are also present in female rats. Furthermore, it is unclear if fear relapse mechanisms show circadian rhythmicity. In experiment 1, rats were fear conditioned and extinction trained at zeitgeber time 4 (ZT4), ZT10, ZT16, or ZT22 and underwent five extinction testing sessions, separated by 6hr, beginning ...


Boulder At The (Tree) Top: Considerations For The Future Of Our Urban Canopy, Natalie Buchholz Jan 2019

Boulder At The (Tree) Top: Considerations For The Future Of Our Urban Canopy, Natalie Buchholz

Undergraduate Honors Theses

This study investigates how canopy cover differs across land use types in six study areas in the City of Boulder, Colorado. Canopy cover can affect the area by buffering extreme weather and reducing heat island impact. Hypotheses state: 1) urban land use areas will have lower canopy cover and higher impermeable surfaces than other land uses; 2) nearby neighborhoods will have similar tree cover; 3) study areas that have high canopy cover receive disproportionately high benefits from increases in canopy cover; 4) all six study areas would benefit from large increases to canopy coverage. In this assessment six GIS surveys ...


(+)-Naltrexone Effects On Anhedonia-Like Symptoms In A Low-Dose Model Of Experimental Autoimmune Encephalomyelitis (Eae), Eric H. Mitten Jan 2019

(+)-Naltrexone Effects On Anhedonia-Like Symptoms In A Low-Dose Model Of Experimental Autoimmune Encephalomyelitis (Eae), Eric H. Mitten

Undergraduate Honors Theses

The demyelinating and inflammatory disorder multiple sclerosis (MS) primarily causes paralysis. However, MS also causes secondary symptoms, including: chronic pain, memory deficits, and depression. Work in our lab has shown that antagonism of toll-like 2/4 receptors with (+)-naltrexone ([+]-NTX) can reverse chronic pain and memory deficits in experimental autoimmune encephalomyelitis (EAE), a rat model of MS. We thus hypothesized that (+)-NTX would also reverse the expression of anhedonia, a symptom of depression defined as an inability to experience pleasure, as measured by saccharin preference testing within EAE. Four separate cohorts of male Dark Agouti and Sprague Dawley rats were ...


Uncovering Evolutionary Changes In The Mitochondrial Genomes Of Lichenized Fungi Within The Order Arthoniales, Dustin Bailey Jan 2019

Uncovering Evolutionary Changes In The Mitochondrial Genomes Of Lichenized Fungi Within The Order Arthoniales, Dustin Bailey

Undergraduate Honors Theses

Lichens are symbiotic organisms that are understudied despite their usefulness to a wide range of disciplines. Studying the genetics of lichen, will contribute to a better understanding of the genetic mechanisms behind symbiosis and fill in grey areas of taxonomic classification of lichens. The lichen order of Arthoniales is even less studied compared to its sister order Lecanorales. This study expands the genomic resources for the former order of lichen and reveals some novel genetic trends found among species within Arthoniales. Some genetic trends have yet to be identified in other lichen species such as the trans-splicing of nad4 among ...


Cheating The (Eco)System: Potential For Invasive Grass Growth Above Treeline, Halina North Jan 2019

Cheating The (Eco)System: Potential For Invasive Grass Growth Above Treeline, Halina North

Undergraduate Honors Theses

Invasive species are increasing in abundance globally and have had detrimental effects on ecosystems by altering nutrient cycling and harming native biodiversity. Generally, high-elevation alpine ecosystems are believed to be the least invaded global biomes. One particularly problematic invasive in the American West is Bromus tectorum, commonly known as Cheatgrass, which is an aggressive competitor and can displace native species. While there is a plethora of research concerning its invasive range in the Great Basin, few studies have addressed what inhibits growth at its high elevation range margin. An earlier study showed that while increased temperatures and N deposition increased ...


Principles And Properties Of Rna Self-Assembly, Gabriel Tauber Jan 2019

Principles And Properties Of Rna Self-Assembly, Gabriel Tauber

Undergraduate Honors Theses

Ribonucleoprotein (RNP) granules are membraneless assemblies of condensed RNA and protein that form through multivalent interactions between the constituent components. Recently, RNA self-assembly has been shown to contribute to the formation of stress granules, which are RNP granules associated with the stress response and neurodegeneration. However, little is understood about the properties of self-assembled RNA. Here, I show that different RNA sequences can self- assemble into condensates with distinct material properties and partitioning preferences in vitro. Due to interactions that minimize surface free energy, RNA self-assembly can generate the spontaneous self-patterning of RNA assemblies. By reducing surface free energy, thereby ...


Exploration Of Hair Cortisol Concentrations And Implications Of Stress In Hunting Dogs On The Bosawas Biosphere Reserve, Nicaragua, Grace Bowland Jan 2019

Exploration Of Hair Cortisol Concentrations And Implications Of Stress In Hunting Dogs On The Bosawas Biosphere Reserve, Nicaragua, Grace Bowland

Undergraduate Honors Theses

This thesis examines the relationships between physiological factors of hair color, sex, nutritional health, and body size (mass) with measures of hair cortisol in domesticated Nicaraguan hunting dogs on the Bosawas Biosphere Reserve. Prior research on cortisol in dogs has been relatively limited to small, homogenous population samples under restricted environmental conditions. This leaves a gap in current knowledge, and a need for larger-scale studies to assess whether current understandings of how cortisol acts in dogs is applicable to dogs within dynamic and heterogeneous environments. The population of hunting dogs examined in this study live in an unpredictable environment in ...


Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey Jan 2019

Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey

Undergraduate Honors Theses

The microbial community of amphibians skin has demonstrated significant importance in amphibian health and disease resistance specifically in response to the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd; Barnhart et al. 2017). Since its discovery in the late 1990s, Bd has contributed to world-wide decline in amphibian populations. Multiple naturally occurring amphibian-skin bacteria have been identified as inhibitors of Bd, including Janthinobacterium lividum (J liv; Harris et al. 2009). The McKenzie group developed a probiotic treatment of J liv as an intervention for a boreal toad population in Colorado drastically declining due to a Bd epidemic. Since wild toads cannot be ...


The Use Of Visualizations In A Biology Classroom At The University Of Colorado At Boulder As An Alternative Way To Access Student Understanding, Katie Ryan Jan 2019

The Use Of Visualizations In A Biology Classroom At The University Of Colorado At Boulder As An Alternative Way To Access Student Understanding, Katie Ryan

Undergraduate Honors Theses

As educational practices start to focus on three-dimensional (3D) learning for students by incorporating practices, concepts, and core ideas, it is vital to understand how alternative forms of idea development affect student understanding. In a revolutionary 2015 commentary, Quillin and Thomas (2015) created the model Drawing-to-Learn to convey the need for drawing in Biology classrooms. The main conclusion was that since other STEM (Science, Technology, Engineering, and Mathematical) disciplines are using drawings to create a deeper understanding of the topic, there is also a need for it in biology. Using similar ideas to the concept of Drawing- to-Learn, 109 students ...


Distance Gradient Of Vocalization Discrimination And Aggression In Neighborhoods Of Rufous-And-White Wrens (Thryophilus Rufalbus), Andrew P. Newgard Jan 2019

Distance Gradient Of Vocalization Discrimination And Aggression In Neighborhoods Of Rufous-And-White Wrens (Thryophilus Rufalbus), Andrew P. Newgard

Undergraduate Honors Theses

Vocalization-based communication networks have been observed in multiple animal taxa. Many territorial animals in these communication networks tend to act differentially towards their neighbors compared to farther-removed strangers given competitive pressure in habitats. My study investigated communication among rufous-and-white wrens (Thryophilus rufalbus), and whether this involves greater aggression towards neighbors or towards strangers. T. rufalbus vocally defend territories year-round and have been shown to exhibit ability to discriminate between vocalizations of neighbors versus strangers (neighbor-stranger discrimination, NSD). I quantified whether T. rufalbus demonstrates different levels of aggression upon hearing played-back vocalizations from close-by neighbors, neighbors of adjacent neighbors, and most ...


Effects Of H-Ras Disease Mutations On Binding To The Ras Binding Domain Of Pi3ky Measured By Micro-Scale Thermophoresis, Justin Martyr Jan 2019

Effects Of H-Ras Disease Mutations On Binding To The Ras Binding Domain Of Pi3ky Measured By Micro-Scale Thermophoresis, Justin Martyr

Undergraduate Honors Theses

H-Ras is a G-protein responsible for the activation of multiple signaling pathways that control cell growth. Our primary interest is examining its role in the regulation of the phosphoinositide-3-kinase (PI3K) signaling cascade, as H-Ras has been previously shown to recruit PI3K to the plasma membrane where this lipid kinase phosphorylates PIP2 to PIP3, a signal for cellular growth. The H-Ras-PI3K-PIP3 signaling pathway is known to be highly oncogenic, with constitutive activation of H-Ras leading to increased PIP3 production and cell growth. We hypothesize that disease-linked mutations on the binding interface between Ras and PI3K increase the ...


Effect Of Quinolizidine Alkaloid Consumption And Seed Feeding Behavior On Caterpillar Growth, Hannah Hartung Jan 2019

Effect Of Quinolizidine Alkaloid Consumption And Seed Feeding Behavior On Caterpillar Growth, Hannah Hartung

Undergraduate Honors Theses

Caterpillars who feed on a wide variety of plant hosts must adapt to the defenses of every plant they feed on. For seed-eating caterpillars this can be particularly difficult because the seed is one of the most heavily defended bodies on a plant. Helicoverpa zea, the corn earworm, is both a seed eater and a generalist, feeding on plants belonging to over 30 families, including both agricultural crops and native plants, such as Lupinus texensis. I studied the corn earworm and L. texensis to answer three questions: i) what is the feeding behavior of these seed-eating caterpillars, ii) how do ...


Using Genetically Encoded Fluorescent Sensors To Accurately Observe The Physiology Of Persister Cells Through Single-Cell Microscopy, Thomas Yao Jan 2019

Using Genetically Encoded Fluorescent Sensors To Accurately Observe The Physiology Of Persister Cells Through Single-Cell Microscopy, Thomas Yao

Undergraduate Honors Theses

Isogenic bacterial communities are capable of harboring a small subpopulation of phenotypically distinguished cells that are transiently resistant to antibiotics. Upon exposure to antibiotics, these cells - termed persisters - enter a dormant state, rendering them tolerant to the antibiotic stimulus. Once the antibiotic stimulus subsides, these cells revert to a normal state and continue dividing to repopulate the community. This feature makes it extremely difficult to eradicate persisters, consolidating their role in the recurrence of chronic infections. While multiple mechanisms can trigger entry into the persistent state, the underlying factor leading to dormancy has been determined to stem from a downregulation ...


The Grass Is Always Greener On The Other Side (Of The Basement Membrane): Prostate Cancer Metastasis As Intracorporeal Dispersal, Matthew Oh Jan 2019

The Grass Is Always Greener On The Other Side (Of The Basement Membrane): Prostate Cancer Metastasis As Intracorporeal Dispersal, Matthew Oh

Undergraduate Honors Theses

Dispersal ecology offers a possible explanation for the behavior of prostate cancer (PCa), which disproportionately metastasizes to the bone. Organisms become more likely to leave their home patch when conditions are unfavorable, with the goal of becoming established in more favorable patches. Similarly, PCa cells are pushed from the prostate tumor by hypoxic stress and pulled toward the bone by the presence of bone stromal cells (BSCs), which support PCa growth and proliferation. When PCa settles in the bone, it leads to the formation of a feedforward loop in which PCa enhances osteoblast differentiation; osteoblasts in turn promote PCa proliferation ...


Quantifying Community Response To Drought: A Trait Based Analysis Of The Xeric Tallgrass Prairie In Boulder, Colorado, Emily Kelman Jan 2019

Quantifying Community Response To Drought: A Trait Based Analysis Of The Xeric Tallgrass Prairie In Boulder, Colorado, Emily Kelman

Undergraduate Honors Theses

Increased severity and duration of drought events in Colorado pose a threat to grassland systems. Utilizing plant traits to analyze community responses to environmental disturbance serves as an accurate mechanism in addressing climate change influences on grassland ecosystems. In this project, I aim to quantify the relationship between five plant traits and drought intensity over time, in order to see if plant traits can capture changes in community structure in response to drought. I calculated the mean value of traits at the community level as well as the amount of variation observed in those values, in order to analyze community ...


Using Random Forest Machine Learning Methods To Identify Spatiotemporal Patterns Of Cheatgrass Invasion Through Landsat Land Cover Classification In The Great Basin From 1984 - 2011, Dylan Murphy Jan 2019

Using Random Forest Machine Learning Methods To Identify Spatiotemporal Patterns Of Cheatgrass Invasion Through Landsat Land Cover Classification In The Great Basin From 1984 - 2011, Dylan Murphy

Undergraduate Honors Theses

In the Great Basin region of the Western United States, the establishment of cheatgrass (Bromus tectorum), an invasive annual grass, has dramatically affected native sagebrush steppe ecosystems. Cheatgrass, and the grass-fire cycle associated with the species, have led to extensive sagebrush community degradation, fragmentation, and eventually, conversion to near-monoculture exotic cheatgrass grasslands. This process has changed regional fire regimes, placing people, property, and native fauna at risk. Despite the known impacts of cheatgrass invasion in the Great Basin, attempts to quantify regional scale changes in ecosystem type have been limited. In this study, a methodology is developed which utilizes Random ...


Benthic Macroinvertebrates In The Alpine Lakes Of Green Lakes Valley, Samuel Yevak Jan 2019

Benthic Macroinvertebrates In The Alpine Lakes Of Green Lakes Valley, Samuel Yevak

Undergraduate Honors Theses

The community composition of different benthicmacroinvertebrates can be used as an indicator of environmental conditions. Benthicmacroinvertebrates are small organisms that lack a backbone (invertebrate), live on the bottom (benthic), and are visible with the naked eye (macro). To better understand the community structure of benthicmacroinvertebrates communities and how they respond to changing environmental conditions, 53 benthic macroinvertebrate samples were collected over the summer of 2018 from three alpine lakes in the Green Lakes Valley, CO. Benthicmacroinvertebrates were sampled from the shoreline, inlet (inflow of water), and outlet (outflow of water) of each sampled lake, within lake ...


The Climb Towards Conservation: Identifying And Mitigating The Effects Of Outdoor Rock Climbing On Surrounding Ecosystems In Colorado, Chloe Sommer Jan 2019

The Climb Towards Conservation: Identifying And Mitigating The Effects Of Outdoor Rock Climbing On Surrounding Ecosystems In Colorado, Chloe Sommer

Undergraduate Honors Theses

Since the 1960s, rock climbing has become an increasingly important player in America’s recreation landscape. Today, rock climbing is a growing contributor to the nation’s $800+ billion-dollar outdoor recreation industry, and indoor and outdoor climbing are more popular than ever. Historically, rock climbers and other outdoor recreationalists have claimed a correlation between recreation and conservation of public lands. Ample evidence suggests, however, that rock climbing still causes an array of negative impacts to ecosystems. This is the first known study to analyze potential impacts of recreational outdoor rock climbing on a large scale with GIS techniques, overlaying geographic ...


Predicting Persisters: Investigating Gene Regulation In Persister Cells, Sowmya Dhanwada Jan 2019

Predicting Persisters: Investigating Gene Regulation In Persister Cells, Sowmya Dhanwada

Undergraduate Honors Theses

Bacterial populations produce a small number of persister cells that remain tolerant to multidrug exposure by becoming metabolically dormant. This inquiry focuses on investigating metabolic gene expression levels in persisters to determine potential predictors of bacterial persistence. Strains from the E. Coli Promoter library were imaged using single cell microscopy, and gene expression levels were measured with the integrated reporter GFP. Persister cells were isolated using ofloxacin. Results indicate that bacterial cells that survive antibiotic exposure exhibit filamentous growth before dividing. Resumption of normal growth morphology is accompanied by increased proteolytic activity in daughter cells, however more investigation is required ...


Developmental And Functional Analysis Of Scutes In The Armored Catfish Corydoras Aeneus, Emily Volk Jan 2019

Developmental And Functional Analysis Of Scutes In The Armored Catfish Corydoras Aeneus, Emily Volk

Undergraduate Honors Theses

Fish scales are specialized biological structures of current interest in innovative materials design because of the combination of protective function, flexibility, and light weight they offer. This study presents a developmental and functional investigation of a particular fish scale structure, the scutes (bony external plates) of the armored Bronze Corydoras Catfish (Corydoras aeneus). Scutes in this model fish species were analyzed via three complementary approaches. First, scutes were documented throughout fish development via high-quality microscope images. These images were subsequently used to inform fabrication of synthetic models to characterize the relationship between scute overlap and overall bending stiffness of scute ...


Evolution Of Gene Regulation In Association With The Origin Of Armor In Stickleback Fishes, Hannah Ghasemi, David Stock Jan 2019

Evolution Of Gene Regulation In Association With The Origin Of Armor In Stickleback Fishes, Hannah Ghasemi, David Stock

Undergraduate Honors Theses

Abstract

Whether the origin of novel structures requires extensive novelty at the genetic level remains an important question in Evolutionary Biology. The bony plates in the dermis (inner layer of the skin) of stickleback fishes (Order Gasterosteiformes) are novel structures that arose as a replacement for scales and whose genetic basis is becoming increasingly well-understood. Previous work has identified an enhancer (a short DNA sequence that regulates the expression of neighboring genes) that is necessary for the expression of the Ectodysplasin (Eda) gene in the bony dermal plates of the Threespine Stickleback (Gasterosteus aculeatus). This gene is necessary for the ...


Genes Regulating Cell Movement During Regeneration In Drosophila Melanogaster Following Radiation Damage, Michelle Ledru Jan 2019

Genes Regulating Cell Movement During Regeneration In Drosophila Melanogaster Following Radiation Damage, Michelle Ledru

Undergraduate Honors Theses

Each year, 1.7 million people are diagnosed with cancer and 610,000 people die from the disease (“Cancer Statistics,” 2018). Ionizing radiation therapy is a commonly used method of treatment for many cancers because it kills cancer cells (Baskar et al., 2012). However, cancer cells that have not been eradicated can proliferate, leading to resistance to treatment (Hanahan & Weinberg, 2011). Drosophila melanogasteris an excellent model organism because they have a short life cycle and share 75% of human disease-causing genes, while the larvae can withstand high amounts of radiation and have regenerative properties. Different genes were investigated to ...


Nanoscale Stiffness Cues Influence Valvular Interstitial Cell Activation To Myofibroblasts, Michaela Wenning Jan 2019

Nanoscale Stiffness Cues Influence Valvular Interstitial Cell Activation To Myofibroblasts, Michaela Wenning

Undergraduate Honors Theses

Surgery is currently the primary treatment option for aortic valve stenosis (AVS) patients, many of whom are ineligible for surgery and are left untreated. AVS is progression is known to differ between males and females, and an understanding of sex-specific mechanisms of disease progression is imperative in developing accurate treatment options for men and women. The development of a nonsurgical therapy for AVS patients requires a deeper understanding of the molecular and cellular mechanisms of AVS progression. Currently, the role of calcium phosphate nanoparticles detected in the aortic valve during early stages of AVS in influencing disease progression and valvular ...


Comparative Analysis Of Dna Isolation Methods For The Human Microbiome, Hannah Chatwin Jan 2019

Comparative Analysis Of Dna Isolation Methods For The Human Microbiome, Hannah Chatwin

Undergraduate Honors Theses

The human microbiome is made up of millions of microbes coexisting in and on us with involvement in health and disease. The exact mechanisms by which this occurs have yet to be fully elucidated. Due to high variability in the composition of each person’s microbiome, it requires large numbers of people to begin to identify some of these processes. A major road block to generating large data sets for analysis is the high cost of DNA isolation from large collections of phenotypically well-characterized human subjects. This study explores the possible application of an inexpensive alternative DNA isolation method utilizing ...


M22 Hormesis In Mouse Embryonic Stem Cell Models, Alexa Mejorada Jan 2019

M22 Hormesis In Mouse Embryonic Stem Cell Models, Alexa Mejorada

Undergraduate Honors Theses

Cryoprotectant toxicity (CT), or the injury due to cryoprotectant (CPA) exposure, remains the most limiting barrier to performing successful organ cryopreservation. An intervention alleviating the stress induced by CT in mouse embryonic stem cell (mESC) models may translate well into tissue and organ models of cryopreservation. Such discoveries could enable large-scale organ banking and, potentially, end the transplantable-organ shortage. In this study, I sought to see if CT could be combated through a hormetic approach. Hormesis will be defined as the negation of the detrimental effects of a high, lethal dosage of a stressor via a prior nonlethal dosage of ...


Characterization Of Siderophore-Host Interactions, Emma Worden-Sapper Jan 2019

Characterization Of Siderophore-Host Interactions, Emma Worden-Sapper

Undergraduate Honors Theses

The role of the gut microbiome in influencing human health has received increasing attention in the past decade, with many of the interactions between symbiont and host being elucidated. A recent study found that the siderophore enterobactin, secreted by E. coli to scavenge iron from its environment, is an essential metabolite for Caenorhabditis elegans (C. elegans) development. The benefit of enterobactin, which appears to be conserved in mammals, carries potential for treating iron deficiency disorder. This thesis focuses on characterizing the nature of the interaction of C. elegans with siderophores other than enterobactin, to assess the uniqueness of the benefit ...