Biology Commons^™

Impact Of Retinoic Acid Receptor Alpha Conditional Knockout On Ovarian Follicle Development In The Mouse, Zlata Bogin

College of Science and Health Theses and Dissertations

When there is abnormal endocrine signaling in the follicles, infertility, and ovarian diseases such as polycystic ovarian syndrome (PCOS), premature ovarian failure (POF), and different types of ovarian cancers may occur. Retinoic acid (RA), a biologically active derivative of vitamin A, is a critical signaling molecule that plays a vital role in various physiological processes, including embryonic development, tissue differentiation, and reproductive function. RA has been observed to influence granulosa cell proliferation through a cell signaling cascade involving Retinoic Acid Receptors (RARs), which have three isoforms alpha, beta, and gamma. We characterized a new retinoic acid receptor alpha (RARA) conditional …

Investigating The Salinity Tolerance Of The Swordtail (Xiphophorus Hellerii), Alexandra Megan Krak

College of Science and Health Theses and Dissertations

The swordtail, Xiphophorus hellerii, is a freshwater fish species native to Mexico and Central America and is commonly used in the tropical aquarium trade. Swordtails have been shown to have limited survival in 6 ‰ salinity (Nanda et al., 2016), suggesting they may have a greater salinity tolerance than previously expected. Using a gradual acclimation method, we examined the salinity tolerance and swim performance of this species. Freshwater-reared female swordtails were housed in 29-gallon aquaria. A control group was held in freshwater throughout the experiment. For the experimental group, the salinity was increased by 2 ‰ every week until 30 …

Characterization Of The Immune Deficiency Pathway During Female Meiosis In Drosophila Melanogaster, Sarah Mashburn

College of Science and Health Theses and Dissertations

Organisms can defend against pathogens by significantly increasing the diversity of their progeny, so that some progeny are more likely to survive infection. This led to the prediction that infection should cause an increase in recombination rates which was seen in a previous study. However, the mechanism that regulates recombination rates in response to infection is not understood and in that study they did not provide a mechanism for how that can occur. In an RNAi screen, our lab found the gene mustard (mtd) is required for normal recombination rates. This gene was previously shown to be part of the …

Observations Of 25 Ghz Methanol Masers In W51a, Peter Wagstaff

College of Science and Health Theses and Dissertations

High mass stars are important because they alone are responsible for creating the heavy elements in the Universe. The observation of high mass star formation remains a challenging problem in astronomy because high mass stars form in densely clustered environments at large distances from us. Therefore, high angular resolution observations are required to unravel the action taking place in these dense environments. Masers can be used to observe distant regions with high angular resolution because masers are compact and bright sources. Class I methanol masers are believed to form in outflows from protostars where the shock generated by the outflowing …

Development Of A 16s Reference Library For Edna Metabarcoding The Freshwater Fishes Of Western Ecuador., Hannah M. Willis, Olivia G. Schweikart, Windsor E. Aguirre

DePaul Discoveries

This project examines the use of the 16S locus to amplify neotropical freshwater fishes native to Western Ecuador in a newly created 16S reference library for DNA barcoding and eDNA metabarcoding applications. Among the orders Characiformes, Siluriformes, Cichliformes, Gobiiformes, Cryprinodontiformes, Gymnotiformes, and Perciformes, a compendium of 105 specimens were sequenced, with 43 representing new 16S sequences previously unavailable on Genbank.

Spatiotemporal Dynamics Of Ticks And Tick-Borne Disease At Neon Sites Across A Sub-Continental Scale, Ana Sofia Rivera

College of Science and Health Theses and Dissertations

Tick-borne diseases in humans such as Lyme disease cases in the United States have doubled between 2004 and 2016. Understanding the dynamics of infectious diseases has long been of interest for ecologists. Tick and tick-borne diseases are influenced by temperature and precipitation at local scales, indirectly through mast seeding in forest trees which increases the abundance of tick hosts (e.g., small mammals), as well as direct effects on survival. Most tick studies occur at local scales that comprise only a small part of their range. The aim of my thesis is to characterize spatiotemporal dynamics of ticks and tick-borne diseases …

Temperature Effects On The Development Of The Axial Skeleton And Body Shape In Astyanax Mexicanus (Teleostei: Characidae), Joseph David Forberg

College of Science and Health Theses and Dissertations

Humans are causing large-scale changes in environmental conditions across the planet including in temperature. Changes in the environmental conditions can lead to phenotypic changes in ectotherms that affect adaptively important traits like body shape and the axial skeleton. Previous studies have shown that temperature changes during development significantly affects body shape and vertebral number in the Mexican tetra Astyanax mexicanus. How these changes arise early in development is not clear. In this study, I examine how changes in developmental temperature affect body shape in larval and juvenile fish, the order of ossification of elements of the axial skeleton, the size …

Characterization Of A Stenotrophomonas Maltophilia Bacteriophage, Edward Eshoo

College of Science and Health Theses and Dissertations

Stenotrophomonas maltophilia is a ubiquitous Gram-negative, multidrug resistant, opportunistic bacterial pathogen that causes various infections in humans. Recently, the use of bacteriophages as therapeutic agents, has gained interest as an alternative to traditional antibiotics. This thesis describes the isolation, purification, and characterization of S. maltophilia bacteriophage Bfi2 and discusses its activity against related, and often co-isolated, bacterial pathogens. Amplification of the phage resulted in clear, well-defined plaques and a titer of 1.73 ± 0.38 x 1011 PFU/ml. Bfi2 demonstrated the ability to lyse 55% of the S. maltophilia strains tested, suggesting that it has a moderate host range. However, the …

Niche Overlap In Sympatric Rocio (Teleostei: Cichlidae) Of Guatemala, Cesar Estuardo Fuentes Montejo

College of Science and Health Theses and Dissertations

Rocio is a small genus of Neotropical freshwater fishes that is distributed in Atlantic drainages of northern Middle America. Two species in the genus exhibit sympatry in the Río Dulce basin (in Izabal, Guatemala), where one species is endemic (R. spinosissima), while the other only includes this area as part of a larger geographic range (R. octofasciata). Unfortunately, the ecology of these species has been poorly studied. This study sought to determine the ecological and morphological differences between these two closely related sympatric freshwater fishes. We hypothesized that R. octofasciata would exhibit greater ecological and morphological …

The Effects Of Triaminopyrimidine Analogs And Gold(I) Chloride Compounds On Cell Proliferation And Apoptosis In Mda-Mb-231 Human Breast Cancer Cells, Robin Redline

College of Science and Health Theses and Dissertations

Breast cancer is a common disease that affects both women and men all over the world. Triple negative breast cancer is an aggressive subtype of breast cancer with poor survival statistics and few available treatment options. Uncontrolled cell proliferation and the ability to avoid programmed cell death, apoptosis, are two shared hallmarks of cancers. Previous research has shown a group of heterocyclic molecules called triaminopyrimidines, not tested in this study, may be effective antiproliferative agents. Previous research has also shown that some gold(I) complexes not tested in this study, may be promising anticancer agents. In this study, a few chemicals …

Phylogenomics And Population History Of Cichlid And Live-Bearing Fish Species In Lowland Neotropical Rivers, Konrad Taube

College of Science and Health Theses and Dissertations

Within Middle America, cichlids and poeciliids account for more than half of the fish biodiversity. This richness in fish fauna highlights the complexity of Middle American biogeography: no other continental area on earth contains within its range the unparalleled abundance of secondary freshwater fish species (fish that can tolerate both saltwater and freshwater). Research into the biogeography of widely distributed Middle American freshwater fish is essential to understanding this unique region.

Three species of freshwater fishes (Belonesox belizanus – Pike killifish, Vieja maculicauda – Black belt cichlid, and Gambusia nicaraguensis – Nicaraguan mosquitofish) are widely distributed across rivers on …

Patterns Of Torso Morphology In Extant Quadrupedal Amniotes And Their Paleontological Applications, Myles M.A. Walsh

College of Science and Health Theses and Dissertations

The relationship between form and function is an overarching theme in the field of biology. Specifically, body size and shape are important factors when considering the biology of an organism. This study examined the torso morphology of a diverse set of 124 extant terrestrial and semi-aquatic amniote taxa using a novel approach to construct approximated torso shape groupings. My study shows the presence of 10 distinct torso shapes within the examined amniotes, and these torso shape groupings were used to evaluate hypotheses associated with diet and limb bone length as well as explore potential evolutionary patterns. Herbivores had a more …

Lgbtqia+ Care Simulation: Examining Participating Students’ Attitude And Comfort, Grezelro Gonzalez

College of Science and Health Theses and Dissertations

Background: The LGBTQIA+ communities face healthcare disparities that contribute to reduced overall health. One factor affecting LGBTQIA+ communities’ reduced overall health is poor health-promoting behaviors or avoidance of care due to healthcare providers’ lack of knowledge, poor attitude, and low comfort levels with LGBTQIA+ care. There are limited studies to date that address nursing students’ attitude and comfort with LGBTQIA+ affirming care interventions outside of lectures. Therefore, the purpose of this study was to evaluate the effect of a simulation intervention on the attitude and comfort of prelicensure nursing students towards providing care to members of the LGBTQIA+ community. Sample: …

Fossil Vertebrates From A Unique Marine Bonebed Of The Upper Cretaceous Niobrara Chalk, Western Kansas, U.S.A.: New Insights Into The Niobrara Vertebrate Paleoecology, Jonathan Allen

College of Science and Health Theses and Dissertations

The Smoky Hill Chalk Member of the Niobrara Chalk is a sedimentary deposit formed in the Western Interior Seaway of North America during the Late Cretaceous. In this study, I examined a unique fossiliferous bonebed from an uncertain horizon within the Smoky Hill Chalk in Gove County, Kansas, U.S.A. Over 40,450 taxonomically identifiable specimens were collected, where they consisted of at least four chondrichthyans, 24 osteichthyans, and two tetrapods, including taxa such as Nanocorax, Squalicorax, Rhinobatos, pycnodontids, Lepisosteidae, Protosphyraena, Pachyrhizodus, ichthyodectiforms, plethodids, Albulidae, Apateodus, Ichthyotringidae(?), cf. Stratodus, Cimolichthys, Enchodus, Acanthomorpha, Platecarpus, and Hesperornithiformes. The diversity of these vertebrates suggests the …

The Effects Of Repeat Concussive Injury On Hippocampal Neurogenesis In Rats, Duane Yu

College of Science and Health Theses and Dissertations

Abstract

A concussion is one of the most common types of traumatic brain injury. Repeat concussion has been associated with an increased likelihood of developing neurodegenerative diseases, such as Parkinson's and Alzheimer's Disease, and chronic traumatic encephalopathy. Although treatments are available to tolerate the symptoms, one potential treatment to address the pathology is to use adult neurogenesis to promote and recruit cells to injury sites for repair. Neurogenesis is the study of new neurons from neural stem cells (NSCs) present in adult humans at the hippocampal dentate gyrus. This study explored whether repeat concussion induces the proliferative capabilities of NSCs …

Physiological Effects Of Sustained Swimming On Salinity Acclimation In Chinook Salmon (Oncorhynchus Tshawytscha), Fritzman Geena

College of Science and Health Theses and Dissertations

Juvenile chinook salmon (Oncorhynchus tshawytscha) encounter a variety of environmental conditions on their migration from freshwater to the ocean. These migrations are physiologically demanding, requiring salmon to reverse their osmoregulatory strategies to successfully acclimate to changing salinity. This reversal occurs primarily at the gills (main osmoregulatory organ) where respiratory and osmoregulatory functions are occurring simultaneously. When subjected to a physiological stressor, the gills will compromise in design to alleviate the most limited function. This tradeoff is known as the ‘osmorespiratory compromise’. This thesis examined whether an osmorespiratory compromise in chinook salmon induced by sustained exercise (a gas exchange stressor) would …

Lab Notes

Scientia

Paleo Showcase; Expert Opinions; School of Nursing Director Appointed; EPISTEM Porject; CSH Honors Award Recipients; Diversity Fellowship

Patenting Antibodies: A Complication In Written Description Jurisprudence, Krisha Yadav-Rajan

DePaul Journal of Health Care Law

No abstract provided.

The Impact Of Temperature On The Early Stages Of The Development Of The Body Axis In The Model Species Astyanax Mexicanus (Teleostei: Characidae), Sara Mohammad Alharbi

College of Science and Health Theses and Dissertations

Environmental fluctuations can change the phenotypic traits of ectotherms. Ectotherms such as fishes are very susceptible to changes in temperature. Recent studies on adults of the Mexican tetra, Astyanax mexicanus, indicate that variation in temperature during development significantly impacts vertebral number and body shape. Since vertebral number and somite number are related, I examined whether temperature significantly impacts somitogenesis and the early development of the body axis in this species. Fertilized eggs of the surface form of lab-reared Astyanax mexicanus were subjected to temperature treatments of 20°C, 24°C, and 28°C, and fixed hourly as they developed until they hatched. Embryos …

Songbird Use Of Problem-Solving Feeders In Urban And Rural Areas, Kayce Miller

College of Science and Health Theses and Dissertations

Behavioral flexibility is important for animals to adapt to novel situations in their environment. It has been suggested that birds living in complex environments (e.g., urban areas) should be more flexible than conspecifics in less complex environments. Birds are a particularly well studied group, where novel foraging problems are used to assess flexibility and problem-solving performance of urban and rural animals of the same species; however, this is most frequently done in a lab setting with wild-caught birds originating from different habitats. Using a field-based method to test problem-solving performance should give additional insight into other factors influencing birds’ flexibility. …

Developing A Transfection Method For Didymium Iridis, Uriel Adolfo Baray

College of Science and Health Theses and Dissertations

The plasmodial slime mold and member of Mycetozoa, Didymium iridis, has been studied in a variety of contexts such as RNA editing (Traphagen et al., 2010; Hendrickson and Silliker, 2010a; Hendrickson and Silliker, 2010b), mitochondrial inheritance (Silliker et al., 2002), biological speciation (Betterley and Collins, 1983; Clark et al., 1991) and mating competency (Shipley and Holt, 1982). Further studies are hindered by the lack of a transfection protocol, which would allow for gene manipulation in D. iridis (hereafter Didymium). Transfection methods developed in the related slime molds, Physarum polycephalum (Burland et al., 1993) and Dictyostelium discoideum (Fey et al., 1995; …

Zygote Gene Expression And Plasmodial Development In Didymium Iridis, Sean Schaefer

College of Science and Health Theses and Dissertations

Didymium iridis is a cosmopolitan species of plasmodial slime mold consisting of two distinct life stages. Haploid amoebae and diploid plasmodia feed on microscopic organisms such as bacteria and fungi through phagocytosis. Sexually compatible haploid amoebae act as gametes which when fused embark on an irreversible developmental change resulting in a diploid zygote. The zygote can undergo closed mitosis resulting in a multinucleated plasmodium. Little is known about changes in gene expression during this developmental transition. Our principal goal in this study was to provide a comprehensive list of genes likely to be involved in plasmodial development. We performed suppressive …

Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo

College of Science and Health Theses and Dissertations

Understanding the diversity of brain morphology is important to understand the evolution of cognitive ability and how ecology and phylogeny have influenced the variation in brain complexity. I examined the morphological variation of the brain in the shark order Lamniformes based on museum specimens and literature. Where I illustrate a wide range of morphological diversity in lamniform brains, my study shows that there is a strong positive correlation between brain size and body size that sharks with a larger brain tend to have a more foliated cerebellum, but that the body weight over brain weight did not correlate with cerebellar …

Integument-Based Inferences On The Swimming Ability And Prey Hunting Strategy Of The Bigeye Thresher Shark, Alopias Superciliosus (Lamniformes: Alopiidae), Joseph Aaron Frumkin

College of Science and Health Theses and Dissertations

Alopias is a group of lamniform sharks characterized by a highly elongate caudal fin with three known extant species: A. pelagicus (pelagic thresher shark), A. superciliosus (bigeye thresher shark), and A. vulpinus (common thresher shark). Alopias pelagicus and A. vulpinus are considered fast swimmers and use their caudal fin to hunt for small schooling fish by stunning them, but the feeding behavior has never been directly observed for A. superciliosus. Under the ecomorphological framework, I examined the following four integumentary variables of selected fast swimming (e.g., A. pelagicus, A. vulpinus, and Lamna) and slow swimming (e.g., Mitsukurina and Megachasma) lamniform …

A New Pachyrhizodontid Fish (Actinopterygii: Teleostei) From The Tarrant Formation (Cenomanian) Of The Upper Cretaceous Eagle Ford Group Of Texas, U.S.A., Maxwell G. London

College of Science and Health Theses and Dissertations

SMU 76938 is a fossil skeleton of a large, nearly complete actinopterygian bony fish housed in Southern Methodist University in Dallas, Texas, USA. It was collected from the Upper Cretaceous Tarrant Formation (middle Cenomanian; ~96 Ma) of the Eagle Ford Group in Tarrant County, Texas, an area where it was near the western margin of the East Texas Embayment during the Late Cretaceous. Although parts of the skull and dorsal fin are damaged, SMU 76938 is relatively complete, especially in the preservation of the caudal fin with its soft tissue outline. The fish has a fusiform body and measures about …

Sex-Specific Personalities In The Purple Marsh Crab, Jillian Sterman, Jessica Barton, Panagiota Delmedico, Samantha Sweeney

DePaul Discoveries

Animals are considered to possess personalities when individuals differ in behavior, and these differences are consistent between situations. Several studies have identified personalities in diverse groups but less is known about personality variation between the sexes. In this study, we examined variation in two key personality traits (boldness, activity) in female and male purple marsh crabs (Sesarma reticulatum) using a semi-field approach. Specifically, we measured boldness and activity on two consecutive days using the same behavioral assays during each time point. Consistency (personality) was determined using Kendall’s coefficient of concordance based on Spearman correlation coefficients for each behavior. …

Behavioral Responses To Gold Nanoparticle Exposure And H2o2-Induced Oxidative Stress In Caenorhabditis Elegans, Rachel Pride, Ashley Wagner

DePaul Discoveries

Gold nanoparticles (AuNPs) have been utilized in many biomedical disciplines, most notably cancer therapy and drug delivery. Recent research suggests that with specific peptide manipulation, AuNPs can deliver drugs across the blood-brain barrier (BBB), allowing for treatment of neurodegeneration and other neurological afflictions. Neurodegeneration has been shown to be caused by oxidative stress. The present experiment aimed to assess the effects of AuNPs on C. elegans behavior that had undergone H₂O₂-induced oxidative stress. It was predicted that worms exposed to both H₂O₂ and AuNPs would have higher survival, mechanosensation, and thrashing rates than …

Effects Of Reduced Ph On Health Biomarkers Of The Seagrass Cymodocea Nodosa, Regan A. Mcenaney

DePaul Discoveries

Ocean acidification is a growing problem that may affect many marine organisms in the future. Within 100 years the pH of the ocean is predicted to decrease to 7.8, from the current ocean pH of around 8.1. Using phenolic acid levels as a stress indicator as well as respiration and chlorophyll content as a measure of health, the effect of lowering pH was tested on the seagrass, Cymodocea nodosa, in a controlled environment. Plant samples, water, and soil were taken from the Bay of Cádiz, Spain, and placed in aquaria in a temperature-controlled room. One control group was left …

On The Composistion Of Cymodocea Nodosa Root Exudate Under Artificial Blue, Green And Natural Light Conditions, Armand Martin, Ben Manriquez, Christian Pompa, Aaron Saper, Kyle A. Grice, Jason Bystriansky

DePaul Discoveries

Seagrasses are identified as a sentinel species: a good indicator of overall marine ecosystem health and function. At the rhizome, they are known to interact with marine bacteria by exchanging energy in the form of glucose and free amino acids secreted through root exudate in exchange for microbe-fixated nitrogen that can be utilized for plant growth. To analyze potential outcomes of possible future changes in light availability, an experiment was designed to collect and analyze the root exudate of Cymodocea nodosa under three light conditions (standard fluorescent light, blue LED, and green LED light). After 72 hours of treatment, the …

Modification Of Host Behavior And Transmission In The Acanthocephalan Acanthocephalus Dirus: Effects Of Development, Intraspecific Conflict, And Host Sex, Sara R. Teemer

College of Science and Health Theses and Dissertations

Parasites are organisms that live on or in another in order to survive. In some cases, parasites require more than one host to complete their life cycle and rely on a predation event for transmission to the next host. Inside the host, the parasite must access host resources to grow and develop from the non-infective to infective stages. At the infective stage, the parasite is able to survive within the definitive host. Development to this stage has been correlated with changes in antipredatory behaviors, body size and color, and reproduction of intermediate hosts in ways that may increase predation by …