Developmental Biology Commons^™

Inside 'N Out: Etv2 Specification Of Hemangiogenic Lineages From Flk1+ Mesoderm, Dereck Antonio Shakeel Alleyne

Arts & Sciences Graduate Student Theses and Dissertations

The cardiovascular system is generated by mesodermal progenitors that give rise to endothelial, hematopoietic and muscle (smooth muscle and cardiomyocyte) lineages. Although vascular endothelial growth factor (VEGF), its receptor, FLK1/KDR and the transcription factor ETV2 are critically required for hemangiogenic specification, Flk1 and Etv2 expression has been observed in other mesodermal derivatives. During gastrulation, mesodermal progenitors are specified to contribute to the cardiovascular system; however, the early divergence of hemangiogenic and muscle progenitors, and their shared marker expression, complicates identification of common mesoderm progenitor populations contributing to both lineages. In this dissertation, I demonstrate how Flk1+ and Etv2+ lineage relationships …

Characterization And Advancement Of Molluscan Venom Gland Cell Model Systems, James V. Parziale

Dissertations, Theses, and Capstone Projects

Venomous mollusks, including cone snails and coleoid cephalopods, produce rich repertoires of bioactive peptides with profound effects on cellular physiology, yet there are few tractable experimental systems that exist to study their development, maintenance, and venom secretion. Although therapeutics such as the cone snail peptide Ziconotide demonstrate the biomedical potential of molluscan venoms, progress in understanding how venom glands form, function, and evolve has been hindered by the lack of reliable husbandry and the complete absence of in vitro cell models. Modern comparative genomics has revealed widespread convergent evolution across venomous lineages, but molluscan datasets remain underrepresented, limiting insights into …

Decoupling Of Reproduction And Lifespan Trade-Off In Caenorhabditis Elegans Through Microbial Programming, Nora M. Villafuerte

LSU Master's Theses

The microbiome is increasingly recognized as a major regulator of host physiology. Using the Caenorhabditis elegans model, we investigated how natural commensal bacteria modulate host reproduction and lifespan through internal egg hatching, a phenotype in which retained embryos hatch within the maternal body. Screening strains from the CeMbio collection identified four focal strains Ochrobactrum BH3, Lelliottia JUb66, Pantoea BIGb0393, and Enterobacter CEent1 that significantly increased internal egg hatching during the late reproductive period. This contrasts with pathogenic bacteria, which induce early-onset internal egg hatching. Across the focal strains, worms exhibited reduced total brood size but an expanded reproductive window relative …

Computational Comparative Genome Analysis Reveals The Characteristics Of Acinetobacter Baumannii C123 Strains, Jennilyn Nicole G. Mendoza

The Lasallian Journal of Health

Acinetobacter baumannii is a Gram-negative, aerobic and multi-drug resistant bacterial pathogen commonly associated with nosocomial infections. This species has several strains and is known to cause pneumonia, septi cemia, meningitis, urinary tract infection and wound infection which are associated with high mortality rates. This study focused on a genome-wide compari son among target C123 strain and 15 other reference strains to predict the overall properties, and resistance mechanisms of the C123 strain. A total of 16 whole genome sequence strains were retrieved from NCBI database for analysis. The selected strains were assem bled and annotated using computational tools. Further more, …

Cell Surface Expansion And Tension Regulation: How Cellular Forces Shape Embryonic Development, Samantha A. Pressman, Sophia M. Micale, Bing He

Wetterhahn Science Symposium Posters

Congenital birth deformities often arise during epithelial morphogenesis, displaying the need to understand the mechanisms underlying this process. Cell shape changes that mediate morphogenesis often require cell surface expansion to accommodate shifts in 3D tissue geometry. Our lab has identified Four Wheel Drive (Fwd), a Golgi-localized phosphatidylinositol 4-kinase (PI4K) IIIβ ortholog, as a regulator for cell surface expansion during Drosophila ventral furrow formation, a well-characterized model for epithelial folding. We hypothesize that Fwd and Rab11, a regulator of exocytosis and endocytic recycling, coordinate the trans-Golgi network and recycling endosomes to promote vesicle trafficking. Using live imaging of fluorescently tagged Fwd …

Effect Of Mid-Range Ultraviolet Light On Avian Embryonic Development, Keelie Hughes

Biology Theses

While it is a known fact that specific environmental conditions must be met to ensure proper embryonic development, the impact of changes in this delicate balance is unclear. Ultraviolet (UV) light has a narrow range of effectiveness in mature tissue, where too little can hinder molecular signaling and too much can cause damage to genetic material. This study exposed in ovo chicken embryos in the preliminary stages of development to mid-range UV radiation to examine developing embryo and tissue morphology using anthropometric methods and comparing proliferative cells among embryos exposed to varying doses of UV light. Additionally, quantitative polymerase chain …

Fgf Signaling Is Necessary For Newt Lens Regeneration, Leo Alexander Napoleon

Honors Theses and Capstones

The Iberian ribbed newt Pleurodeles waltl can regenerate the lens by transdifferentiating iris pigmented epithelial (IPE) cells into lens epithelial cells (LECs), but the mechanism by which this occurs remains largely uncharacterized. We aim to mechanistically show an early and critical role for FGF signaling by using small molecules to inhibit FGF receptors and observe the histological and intracellular effects. Two inhibitors were found to completely stall lens regeneration. Cell cycle analysis revealed decreased DNA synthesis and uniformly low but unchanged entry to mitosis under signaling inhibition by staining for EdU incorporation and phospho-histone H3 (pH3), respectively. Western blot revealed …

Comparing The Differences Of Hsp90Α And Hsp90Β In Native Protein Complex Incorporation, Daryna Serediuk

Honors Theses and Capstones

Epichaperomes are long-lasting, stable assemblies of chaperones, co-chaperones, and associated factors that facilitate cell survival in maladaptive cellular states. Their inhibition has emerged as an attractive therapeutic strategy for the treatment of cancer and neurodegenerative diseases (Rodina et al., 2016). Epichaperomes are hallmarks of robust proliferation in cancer cell populations across many cancer types and are abundantly present in several stem cell varieties, including induced pluripotent stem cells, human embryonic kidney cells, and cancer stem cells (Kishinevsky et al., 2018).

The core protein of the eukaryotic heat shock protein machinery, Heat Shock Protein 90 (Hsp90), is a central chaperone that …

Exploring Anticholinergic Neurotoxicity: Diphenhydramine's Impact On Neuro-2a Cell Morphology, Expression, And Viability, Jordan B. Mcintyre

Honors Undergraduate Theses

Anticholinergic medications, such as diphenhydramine (commonly known as Benadryl), are increasingly recognized for their association with cognitive impairment and neurodegenerative disease. These medications, which inhibit the action of acetylcholine, a neurotransmitter essential for the formation and utilization of the central and peripheral nervous system, have been implicated in conditions such as dementia and may impact fundamental cellular processes like neurogenesis and cell proliferation. This study investigates the effects of diphenhydramine on neurogenesis when introduced to Neuro-2a cells during differentiation. For all studies cells were plated on coverslips or in 6-well plates with differentiation media containing 0 ng/mL, 50 ng/mL, …

Tmem116 Crispr-Mediated Knockout Prevents Proper Lens Regeneration In Iberian-Ribbed Newts, Damien T. Mann

Honors Theses and Capstones

Eye diseases like cataracts, age-related macular degeneration (AMD), and glaucoma are widespread and detrimental conditions affecting many people across the globe. While there are reliable and successful treatments for those with cataracts that can reverse vision impediments, others like glaucoma and AMD have limited treatment options. Additionally, eye damage resulting from these conditions is commonly irreversible, establishing a need for new treatment options. The Iberian-ribbed newt, Pleurodeles waltl, is a salamander species primarily studied for their amazing regenerative capabilities. Particularly, these newts are capable of de novo lens regeneration after a complete resection, providing a unique opportunity to study regeneration …

The Role Of Tumor Microenvironment In Glioblastoma Multiforme(Gbm) Therapeutic Resistance, Kwesi E. Taylor

Master's Theses or Doctor of Nursing Practice

Despite significant advances in cancer research and treatment, Glioblastoma multiforme (GBM) remains one of the most difficult cancers to treat effectively, with minimal improvement in long-term survival rates over the past few decades. This is largely attributed to tumor heterogeneity and the ability of tumor cells to develop adaptive resistance mechanisms supported by the tumor microenvironment (TME). Although the TME is recognized as a key contributor to tumor progression and therapeutic resistance, the underlying molecular pathways and regulatory genes remain incompletely understood. This study investigated the role of the tumor microenvironment in GBM therapeutic resistance using a bioinformatics approach. Single-cell …

How Semiflightless Birds Adapt: A Survey From Barú, Costa Rica, Eli P. Laloudakis

Scripps Senior Theses

When we think of birds, we think of flight. Because of this, scientific research often focuses on how birds evolved flight and how their wings function during flight. However, not all birds can fly or fly well, as wings wax and wane on developmental, seasonal, and evolutionary time scales (Dial and Heers 2021). Consequently, rudimentary wings can be found in developing birds, secondarily flightless or semiflightless birds, birds that undergo simultaneous molts, and extinct theropods with “protowings” (structures that preceded fully functional wings). Secondarily flightless and semiflightless birds often evolve where there is no/low predation, abundant year-round food supply, and …

Analyzing Early Medieval Perspectives Of Fetal Development, Nivedha Srinivasan

Honors Undergraduate Theses

This thesis examines early medieval perspectives of fetal development by analyzing two manuscripts: British Library, Cotton Tiberius A III and Leiden University, Vossianus lat. Q69. This study will investigate how knowledge of pregnancy was shared throughout England before the establishment of universities. Interest in medieval reproductive language has piqued in importance in recent years, especially due to modern legal debates surrounding reproductive rights. By examining descriptions of the nine months of fetal development in these two manuscripts, as well as in widely known earlier medical texts like Pliny’s Natural History and Vindicianus’ Gynaecia, this research explores how monastic writers in …

Stem Cell-Derived Developmental Models For Translational Evaluation Of Disease And Therapy, Maria B. Paredes-Espinosa

Electronic Theses & Dissertations (2024 - present)

Human development as well as congenital and adult diseases emerge from coordinated interactions among multiple cell types, regulatory programs, and tissue compartments that remain largely unresolved. Conventional simple lineage-restricted in vitro systems poorly capture this complexity. My dissertation uses human stem cell-derived developmental models to study human cardiac morphogenesis and heart diseases and application of a networked neuron platform to explore senescence-associated neurodegeneration impact on Alzheimer’s neurons.

Elongating multi-lineage organized cardiac (EMLOC) gastruloids are a synthetic embryology model that co-generates contractile cardiomyocyte populations alongside mesenchymal, endothelial, epicardial-like, neural crest-associated, and neuronal cells within a shared in vitro developmental environment. Single-cell …

Multifunctional And Adaptive: Tracking How Fibroblasts Respond To Tissue Injury And Facilitate Tissue Remodeling, Joey R. Tavarez

Electronic Theses & Dissertations (2024 - present)

Fibrosis is characterized by an accumulation of proteins in the extracellular matrix (ECM) that results in altered tissue architecture and reduced organ function. In the salivary glands, fibrosis leads to loss of saliva, dysbiosis of the oral microbiome, an increase in oral infections, difficulty in digestion of food and an overall reduction in the quality of life. Understanding the progression of fibrosis and how it affects human health is a crucial step for designing effective therapeutics. Understanding fibroblast function is integral to advancing the field due to the many roles they play in maintaining the ECM. To perform preliminary analysis, …

Modeling Inherited Retinal Disease In Zebrafish, Meet Patel

Theses and Dissertations--Biology

Inherited retinal diseases (IRDs) affect millions of people worldwide. Majority of IRDs are caused by degeneration of rod and cone photoreceptor cells (PRCs) due to gene mutations. The overarching goal of my dissertation is to model and evaluate the molecular role of various gene candidates involved in IRDs such as cone rod dystrophy (CRD) and retinitis pigmentosa (RP).

Mutations in CDHR1, a photoreceptor specific cadherin have been associated with CRD and recapitulated in mouse CDHR1 knockouts. However, the molecular function of CDHR1 remains unknown. CDHR1 has been shown to localize at the leading edge of murine rod nascent outer segment …

Patterns Of Ovarian And Gonadotropin Hormones In Emerging Adult Oral Contraceptive Users, Summer Mcormond

Undergraduate Research Posters

Oral contraceptives (OCs) are often initiated during adolescence and emerging adulthood, a period of continued maturation of the hypothalamic–pituitary–gonadal (HPG) axis. Because hormonal exposure during this window may shape emotional, biological, and reproductive outcomes, it is important to understand the specific formulations young women take and the hormonal profiles these formulations produce. This study characterizes OC formulation features and measured hormone levels in young adult OC users (n = 30).

Ethinyl estradiol (EE) doses ranged from 0.01–0.035 mg (mean = 0.022 mg), with 70% using ≤0.02 mg. Pill regimens included 21/7 packs (83%), 24/4 packs (10%), and 84/7 regimens (3%). …

Epigenetic Modifications In Dedifferentiated Liver Cells To Restore Lost Liver Function, Shreya Sharma

Masters Theses

The goal of the study is to investigate whether the epigenetic modifications can enhance the restoration of liver gene expression in dedifferentiated hepatoma cells or not. For the study, we used dedifferentiated H11 hepatoma cell lines which overexpress one of a panel of introduced candidate liver-enriched transcription factors H11-HNF1a, H11-CREB3L3, H11-CREG1, H11- HHEX, H11-HNF6, and H11-IGFBP1. The cells were treated with the DNA methyltransferase inhibitor 5-azacytidine and the histone deacetylase inhibitor sodium butyrate, both individually and in combination. Gene expression analysis was determined by RT-qPCR, which revealed that while transcription factor overexpression alone produced limited activation, epigenetic modulation, particularly Histone …

Immunohistochemical Analysis Of The Effects Of Streptozotocin-Induced Diabetes On Mouse Testis, Rory E. Field, Brianna R. Demaio, Hannah R. Fioramonti, Makenna M. Landis, Jing Xu

Montview Journal of Research & Scholarship

Because diabetes mellitus (DM) poses harm to the reproductive systems of humans and mice on both the cellular and histological levels, we sought to understand the effects of streptozotocin-induced (STZ) diabetes mellitus on the spermatogenesis and Anti-Müllerian hormone (AMH) production of mice. The structural integrity of the testes is disrupted due to the high levels of oxidative stress caused by DM, which also hinders spermatogenesis. Advanced glycation end products (AGEs) have been found to induce autophagy in Sertoli cells, and the Sertoli cells of diabetic models have fewer tight junctions between them. This disorganization and decreased integrity of the seminiferous …

Pediatric Glioblastoma Molecular Mechanisms, Ariana Trabachino, Joshua Owens

Student Scholar Symposium

Powerpoint presentation