Life Sciences Commons^™

Functional Characterization Of Cancer-Associated Dna Polymerase Ε Variants, Stephanie R. Barbari

Theses & Dissertations

Replicative DNA polymerases ε (Polε) and δ (Polδ) achieve high fidelity DNA synthesis through a precise balance of polymerization and exonucleolytic proofreading. Errors that escape proofreading are corrected by DNA mismatch repair (MMR). Ultramutated human cancers with proficient MMR carry alterations in the exonuclease domain of Polε, which were initially predicted to abolish proofreading. However, functional studies in yeast of the most recurrent Polε-P286R variant suggested defects beyond a loss of exonuclease activity. Indeed, biochemical analysis of the yeast Polε-P286R analog revealed increased polymerization capacity in addition to decreased proofreading, which enables efficient mismatch extension and bypass of replication-blocking non-B …

Understanding The Impact Of Chlamydia Trachomatis Infection On Host Vesicular Trafficking, Lisa M. Jorgenson

Theses & Dissertations

Chlamydia trachomatis is a highly evolved obligate intracellular bacterial pathogen. During infection, organisms reside within a host epithelial cell in a membrane-bound vacuole called the inclusion. The inclusion membrane contains both pathogen and host components, including unique chlamydial type III effector proteins called Incs and host lipids like cholesterol and sphingomyelin. The inclusion membrane serves as the main barrier between the bacteria and the host cytosol, and thus, functions as the platform supporting host-chlamydial interactions. Via the inclusion membrane, C. trachomatis intercepts components of host vesicular traffic including many host SNARE proteins, which are a conserved family of eukaryotic proteins …

Identifying And Knocking Out Non-Visual Opsins In The Optic Tectum Of Zebrafish Larvae, Sarah Jarrett

Undergraduate Honors Theses

Deep brain photoreceptors (DBPs) are non-visual photoreceptors found in the brains of non-mammalian vertebrates like zebrafish. While using optogenetic techniques in our lab to photo-activate the ear (by expressing the light-gated channel: channelrhodopsin) in efforts of identifying optic tectum (OT) neurons that respond to and integrate auditory and visual stimuli, we found that violet light was able to elicit OT neuronal activity. OT activity was also detected in cases when visual and auditory stimulation was not possible due to removal of the eyes and absence of the exogenously expressed channelrhodopsin, respectively. Analyzing OT single-cell sequencing data of 7day post fertilization …

A Pkcα-Mediated Growth Suppressive Mek-Erk Signaling Axis In Intestinal Epithelial Cells, Navneet Kaur

Theses & Dissertations

Members of the protein kinase C (PKC) family of serine/threonine kinases are involved in regulation of fundamental cellular functions, including proliferation, differentiation, survival, migration, and transformation. Increasing evidence points to anti-proliferative and tumor suppressive role of PKCs. Our laboratory and others have reported that the classical PKC isozyme, PKCαnegatively regulates proliferation and tumorigenesis in the intestinal epithelium. Our laboratory has further determined that PKCα signaling induces a program of cell cycle withdrawal in intestinal epithelial cells that involves downregulation of the pro-proliferative proteins, cyclin D1 and Id1, and upregulation of the cyclin dependent kinase (CDK) inhibitor, p21^Cip1. Unexpectedly, …

Poor Acclimation To Experimental Field Drought In Subalpine Forest Tree Seedlings, Alex Goke, Patrick H. Martin

Biological Sciences: Faculty Scholarship

The ability of tree species to acclimate and tolerate projected increases in drought frequency and intensity has fundamental implications for future forest dynamics with climate change. Inquiries to date on the drought tolerance capacities of tree species, however, have focused almost exclusively on mature trees with scant in situ work on seedlings, despite the central role that regeneration dynamics play in forest responses to changing conditions. We subjected naturally established seedlings of co-dominant subalpine conifer species (Abies lasiocarpa and Picea engelmannii) in the southern Rocky Mountains to 2 years of in situ summer precipitation exclusion, simulating summer drought …

Distribution, Abundance And Natural Enemies Of The Invasive Tomato Leafminer, Tuta Absoluta (Meyrick) In Kenya, G. Kinyanjui, F. M. Khamis, F. L.O. Ombura, E. U. Kenya, S. Ekesi, S. A. Mohamed

All Peer-Reviewed Publications

Tuta absoluta (Meyrick) has become a serious menace to sustainable production of tomato in Kenya. A survey was conducted between April 2015 and June 2016 to determine its distribution, abundance, infestation, and damage levels on tomato, and associated natural enemies. Trap counts of T. absoluta moths were recorded in all surveyed 29 counties, which indicated its nationwide distribution irrespective of altitude. Tuta absoluta was present in both open fields and greenhouses. The highest moth/trap/day was 115.38 ± 15.90. Highest leaf infestation was 92.22% and the highest number of mines and larvae per leaf were 3.71 ± 0.28 and 2.16 ± …

Who Pays To Clean Up What A Dying Industry Leaves Behind?, Audrey Carleton

Capstones

As the birthplace of oil and gas, Pennsylvania is home to the highest number of orphaned abandoned oil and gas wells in the country — an estimated 300,000 to 500,000 dot the Keystone State, all remnants of a dying industry. These wells emit methane, a potent greenhouse gas, and have, for decades, caused alarm to hundreds of residents, documents obtained in a months-long capstone investigation show. The state is currently plugging 10 to 12 abandoned wells per year, on average, out of hundreds of thousands, in part because it has not collected enough in cleanup funds from producers to fund …

Probing The Role Of Astrocytes In The Pathology Of Fragile X Syndrome With Human Stem Cells, Baiyan Ren

Theses & Dissertations

Fragile X syndrome (FXS) is an X-linked neurodevelopmental disorder related to intellectual disability and the most common monogenic cause of autism spectrum disorder. FXS is mainly caused by an expansion of CGG repeats in the 5’-untranslated region of fragile X mental retardation 1 (FMR1) gene, leading to the loss of expression of fragile X mental retardation protein (FMRP). Astrocytes are the most abundant glial cells in the central nervous system (CNS). Loss of FMRP in astrocytes has been found to contribute to structural and functional synaptic deficits in the Fmr1-KO mouse model. The contribution of human astrocytes, however, to the …

Immunological Factors Associated With Siv/ Shiv Persistence In Diverse Tissue Niches, Omalla A. Olwenyi

Theses & Dissertations

The significant challenge towards a successful HIV cure lies in eradicating persistent viral reservoirs across diverse tissue niches. As a result, HIV-infected individuals have to resort to lifelong antiretroviral therapy. Recent news of supposed HIV eradication in a second patient has further re-invigorated the fields of HIV cure. However, a few barriers remain, such as the lack of currently available assays to accurately quantify viral reservoirs, limited information on cellular factors associated with persistence, and varied dynamics of the viral reservoir in various body compartments. Lastly, HIV-infected individuals live different lifestyles stemming from comorbid substance abuse including consumption of morphine, …

Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring

IGC Proceedings (1977-2023)

The objectives of this study were to test the possibilities of using different farm animals for landscape care on extensive pasture, taking into account their particular performance, and to analyse alterations of the flora in consequence of grazing by different animals and various pasture management. Salers had the highest (836g/d) and Galloways (584g/d) the lowest live weight gain as compared with the other breeds (771g/d). Lambs had higher live weight when grazing together with cattle and horses (mixed grazing) than under one species grazing. The number of legume increased and that of grass decreased. Following 3 years the grazing animals …

Animal Production From Tropical Pastures Renovated By Subsoiling And Fertilization In The Cerrados Of Brazil, Valéria P. B. Euclides, Manuel C. M. Macedo, M. P. Oliveira

IGC Proceedings (1977-2023)

A grazing trial was conducted, to study the effects of fertilization on the maintenance of the productivity of four tropical grasses. The paddocks were subsoiled, and dived into halves: one (LF1) received 400 kg/ha of a fertilizer formula 0-20-20.and the other (LF2) 800 kg/ha of the same fertilizers, in January 1995. Annually, 50 kg/ha of N was applied. The productivity on LF2 pastures was greater than that on FL1 pastures, averaging 520 and 410 kg of liveweight gain/ha/year. A double strategy should be followed to sustain animal production in the savanna: maintain soil P over a critical value of 3.0 …

Performance Of Nellore Cattle Under Two Grazing Management Systems, L. De A. Corrêa, Maurício M. De Alencar, Rogério T. Barbosa, P. F. Barbosa, Geraldo M. Da Cruz, I. U. Packer, C. A. Cordeiro

IGC Proceedings (1977-2023)

The objective of this study was to evaluate the effects of grazing intensification on birth weight (BW), weaning weight (WW, standartized to 205 days), average daily gain from birth to weaning (ADG), and gestation length (GL) of calves, cow weight at calving (CWC) and at weaning (CWW), cow condition score at calving (CCC) and at weaning (CCW), and BW/CWC (BWR), WW/CWC (WWRC) and WW/CWW (WWRW) ratios. One hundred and sixty eight Nellore calves born in 1998 and 1999, out of dams maintained in two grazing management systems were evaluated: an extensive 1.0 animal unity (AU). ha^-1 system on unfertilized …

Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata) grown alone or with ladino white (Trifolium repens) and red (T. pratense) clovers, provides a high quality March to June pasture. However, many beef producers have their cows calving in January-March, thus producing offspring that are too young to utilize spring forage well. As an alternative, some producers have their cows bred so that calves are born in autumn (September-November). By spring, these calves are old enough to consume pasture forage. The few earlier studies on early weaning of fall-born calves consist of drylot feeding of high quality hay or concentrates. …

Relationships Among College-Level Science Course Enrollment, Environmental Perception, And Pro-Environmental Attitude: Evidence From The Us General Social Survey, Mazbahul G. Ahamad, Fahian Tanin

Department of Agronomy and Horticulture: Faculty Publications

Understanding pro-environmental attitudes is critical to encouraging pollution-minimizing behaviors. Therefore, identifying associated factors is essential for understanding different types of pro-environmental attitudes. We aimed to investigate the associations among individuals’ college-level science course enrollment and their perceptions of the level of spending to improve and protect the environment, as well as their pro-environmental attitudes. We used nationwide population-based cross-sectional survey data from 2,348 individuals obtained from the General Social Survey in the United States. An ordered logistic model was used to examine the associations among college-level science course enrollment, environmental perception, and pro-environmental attitude. We found that science course enrollment …

Intrinsically Disordered Protein Regions In Human Evolution And As Therapeutic Targets, Karen Paco Mendivil

KGI Theses and Dissertations

Intrinsically disordered proteins (IDPs) and IDP regions (IDPRs) fail to form stable structures but have important biological functions via interacting with various molecular partners (proteins, DNA, RNA, glycosaminoglycans). We hypothesized that IDPRs are potential targets for therapeutics development because they are reservoirs of evolutionary innovation, and they play crucial roles in adaptation to pathogens.

We first studied the evolution of IDPRs in the human proteome and compared it with the proteome of non-human primates. We have found that evolutionary young protein-coding genes have included low conserved regions in the N-terminal part of proteins, and such regions are linked to high …

Skin Bacterial Metacommunities Of San Francisco Bay Area Salamanders Are Structured By Host Genus And Habitat Quality., Shannon Buttimer, Obed Hernandez-Gomez, Erica Bree Rosenblum

Natural Sciences and Mathematics | Faculty Scholarship

Host-associated microbial communities can influence physiological processes of macroorganisms, including contributing to infectious disease resistance. For instance, some bacteria that live on amphibian skin produce antifungal compounds that inhibit two lethal fungal pathogens, Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). Therefore, differences in microbiome composition among host species or populations within a species can contribute to variation in susceptibility to Bd/Bsal. This study applies 16S rRNA sequencing to characterize the skin bacterial microbiomes of three widespread terrestrial salamander genera native to the western United States. Using a metacommunity structure analysis, we identified dispersal barriers for these influential bacteria between salamander …

Characterization Of Landfill Leachate For Enhanced Metal Recovery, Hanna Fulford, Amisha Shah, Inez Hua, Nadezhda Zyaykina, Lori Hoagland, Alejandro Rodriguez Sanchez, Umut Bicim

Discovery Undergraduate Interdisciplinary Research Internship

Landfills contain a trove of valuable materials, such as critical, precious, and rare earth metals, that are integral to the United State’s economy and national security. The leachate that filters through landfills picks up these materials, which allows for the possibility of recovery. For this research, samples will be analyzed from landfills throughout the Midwestern United States to provide a baseline on water quality constituents, elements present, and microbial activity. Preliminary data for this study was acquired by analyzing samples of landfill leachate from a landfill in northern Indiana. pH readings indicate that the leachate is slightly basic. It also …

Utilizing Isothermal Titration Calorimetry For Measuring Beta-Galactosidase Activity In Liquid Dairy Products, Eliza Anne Brock

Theses and Dissertations

This research explores Isothermal Titration Calorimetry as a method for measuring beta-galactosidase activity directly and continuously in milk, sweet whey, sweet whey permeate, acid whey, and acid whey permeate. Beta-galactosidase in various concentrations was injected into each of the liquid dairy products spiked with lactose to verify if the heat rate from the enzymatic reaction could be observed. In addition, a consistent concentration of beta-galactosidase was injected into various concentrations of lactose in the products, to observe the heat rates from the enzymatic reaction. There was exothermic activity that never returned to baseline demonstrated in milk, sweet whey, and sweet …

Phage Commander, An Application For Rapid Gene Identification In Bacteriophage Genomes Using Multiple Programs, Matt Lazeriff, Geordie Ryder, Sarah L. Harris, Philippos K. Tsourkas

Computer Science Faculty Research

The number of sequenced bacteriophage genomes is growing at an exponential rate. The majority of sequenced bacteriophage genomes are annotated by one or more of several freely available gene identification programs (Glimmer, GeneMark, RAST, Prodigal, etc.). No program has been shown to consistently outperform the others; thus, the choice of which program to use is not obvious. We present the Phage Commander application for rapid identification of bacteriophage genes using multiple gene identification programs. Phage Commander runs a bacteriophage genome sequence through nine gene identification programs (and an additional program for identification of tRNAs) and integrates the results within a …

Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph

Theses and Dissertations

Elephants have shown remarkable olfactory capabilities. Their sense of smell impacts their foraging choices, behavior, and ultimately, survival. Being able to detect a target odor can allow elephants to locate specific resources, identify threats, and find receptive conspecifics. Previous studies have shown that elephants can consistently detect target odors, but have not identified the limits of this detection. Thus, to investigate the extent of elephants’ odor detection capabilities, we tested Asian elephants in a two-step odor discrimination task. First, we investigated whether elephants could detect odors at varying levels of dilution after a training procedure, and then whether they could …

Restoring Polyhyrdoxybutyrate (Phb) Depolymerase Expression In A Bald Mutant Of Streptomyces Sp. Sfb5a, Youmna Moawad

Honors Projects

Polyhydroxybutyrate (PHB) is a biodegradable, plastic-like polymer produced by some bacteria and degraded by others. The filamentous bacterium Streptomyces sp. SFB5A degrades PHB for growth using an extracellular PHB depolymerase, encoded by the phaZ gene. A morphological mutant of this bacterium, bld4, cannot form aerial filaments and cannot produce PHB depolymerase, despite having the phaZ gene. The inability to synthesize PHB depolymerase may be due to a mutation in a gene encoding one of its transcriptional regulators. A gene (lrp) coding for a potential transcriptional regulator is located 2,700 base pairs upstream from phaZ. Our goal …

Population Ecology Of The Queensnake (Regina Septemvittata) In An Urban Creek, 2008 To 2019, Rachel Beiler, R. Elliot Miller, Norman Reichenbach

Faculty Publications and Presentations

Habitat fragmentation is a common result of urbanization and species living in these fragments are at risk of extirpation. We conducted a 12-y (2008–2019) capture-mark-recapture study on snakes living in a 593-m section of Rock Castle Creek flowing through an urban area in central Virginia, USA. Our study site was occupied primarily by Queensnakes (Regina septemvittata). We used data from 168 individual Queensnakes to examine several aspects of their population ecology including survival rates (0.52), reproductive effort (21.3% juvenile to adult ratio), growth rates (68% and 30.6% increase for 1 to 2 y-old and 2 to 3+ y-old snakes, respectively), …

Effects Of Catharanthine On Dopamine Release In The Nucleus Accumbens And Ethanol Consumption, Emily Baldwin

Undergraduate Honors Theses

This thesis discusses the history of catharanthine and related compounds, and their potential anti-addictive properties. Current research is exploring possible mechanisms of these properties. Past studies have found catharanthine has effects on neurons that project to the mesocorticolimbic system, an area implicated in addiction. We have seen that catharanthine decreases evoked dopamine (DA) release but increases basal DA release. This is the first study to investigate catharanthine’s effect on DA transmission in vivo. Using microdialysis, we determined the effect of catharanthine on DA in the nucleus accumbens of the striatum. This study determines the effect of different doses of …

Molecular Mechanisms Of Aberrant Protein Glycosylation In Pancreatic Cancer Stemness And Metastasis, Frank Leon

Theses & Dissertations

A myriad of genetic and other abnormal changes underlies the aggressiveness and dissemination properties observed in pancreatic cancer (PC). Aberrant protein glycosylation is a commonly observed feature in PC. The modification of protein O-glycosylation is mediated by glycosyltransferases, which attach and sequentially elongate monosaccharides on Serine/Threonine (Ser/Thr) motifs. Aberrant glycosylation is recognized as an emerging hallmark of cancer where a disruption in normal glycosylation results in irregular O-glycans.

This dissertation research has investigated the consequences of aberrant protein glycosylation on stemness and enhancement of metastatic properties in pancreatic ductal adenocarcinoma (PDAC). Several publications have reported aberrant O-glycosylation increases in oncogenic …

Comparing Macroinvertebrate Total Abundance And Total Biomass On Five Substrate Types From Upstream To Downstream On The North Branch Of The Au Sable River, Paul David Dingman

Masters Theses

The North Branch of the Au Sable River is located in the northern lower peninsula of Michigan and is known for prolific hatches of Ephemeroptera (mayflies), Trichoptera (caddisflies), and Plecoptera (stoneflies). Macroinvertebrates play an important role in processing and recycling organic material in rivers and are a valuable food source for trout. In 2018, anglers were reporting catching fewer numbers of brook and brown trout (Salmo trutta and Salvelinus fontinalis). The Michigan Department of Natural Resources (MDNR) determined significantly lower abundance than the historical average. We hypothesized that trout abundances were lower due to a lack of prey …

Student Pharmacists’ Emotional Responses And Coping During The Covid-19 Pandemic, Hannah E. Johnson, Deaundre Bumpass, Aric Schadler, Jeffrey Cain

Journal of Wellness

Introduction: Health professions students, including student pharmacists, have been impacted by the coronavirus disease 19 (COVID-19 pandemic) as schools have transitioned to remote learning and cancelled milestone events. During times of crises, media consumption and hobby participation also impact well-being. The adverse emotional responses and coping strategies of student pharmacists amidst the COVID-19 pandemic have not been evaluated, nor have factors that may contribute to emotional responses. The purpose of this study is to determine Doctor of Pharmacy students’ emotional responses and coping precipitated by the COVID-19 pandemic, and the influence of media use, working status, and participation in hobbies. …

Energetic Tradeoffs, Infection, And Immunity In Wild Chimpanzees Of Uganda And Tanzania, Sarah Renee Phillips

Anthropology ETDs

Infectious disease is a primary source of mortality for most mammal species, but scientists have little understanding of factors driving variation in infection and immunity between individuals, populations, and species in the wild. Life history theory provides an evolutionary framework for delineating distribution of available energy to competing physiological demands, including growth, reproduction, and maintenance. Early life reproduction should be favored over late life survival, but, in long-lived species, reproductive success is strongly tied to survival to old age. Slower pace of reproduction could allow investment in immunity, reducing risk of morbidity and mortality to infectious disease. Additionally, several host …

Exploring The Biofilm Of Candida Auris As It Relates To Persistence In Clinical Setting And Susceptibility To Antimicrobials, Bethany Butts

Master of Science in Integrative Biology Theses

The rapid rise of drug-resistant pathogens is a global health concern. Known pathogens are acquiring resistance to many commonly used drugs, while new drug-resistant pathogens are emerging. These resistant pathogens are responsible for many healthcare-associated infections (HAI) [1, 2]. Candida auris is among these emerging drug-resistant pathogens, first described in 2009. The CDC labels C. auris at the highest level of global public health threat [3,4]. Effective methods of decolonization and control of the organisms have yet to be established, as it is resistant to many agents used for microbial control. Recent research has found that C. auris has the …

Restricted Microbial Presence, Activity, And Community Structuring Within Dry Valley Soils Of Antarctica, Scott Fillerup George

Theses and Dissertations

The McMurdo Dry Valley region is the largest ice-free area of Antarctica. Harsh abiotic conditions of the polar desert ecosystem, including extreme cold, aridity, and limited nutrient availability select for unique taxa. The comparatively simple terrestrial ecosystem is well-suited for investigating edaphic influences on microbial presence, activity, and community structuring. The Dry Valleys are viewed as a useful analog for Mars astrobiology investigations. However, most biotic investigations have been focused on lower elevations, where an understanding of edaphic effects on microbial communities within its generally more favorable conditions has emerged. Transiently wetted Dry Valley water tracks may be analogous to …

Rapid Source To Sink Transition In A Mixed-Conifer Forest Following Stand-Replacing Fire, Ryan Matthew Schulze

Biology ETDs

Mixed-conifer forests play an important role in the Southwestern USA’s regional carbon cycle by sequestering and storing large amounts of atmospheric carbon onto the landscape. Despite this, little is known about how large, stand-replacing fire alters ecosystem carbon sink-source dynamics. In this study, we used eddy covariance to quantify how stand-replacing fire altered forest sink strength, and the sensitivity of carbon uptake to soil and atmospheric drought in a mixed-conifer forest located in The Valles Caldera National Preserve, NM. We found that the post-burn ecosystem returned to an annual net sink of carbon in the year immediately following the fire, …