Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 9 of 9
Full-Text Articles in Entire DC Network
Developmental Exposures To Pfas Mixtures Impair Elongation Of The Exocrine Pancreas In Zebrafish (Danio Rerio), Emily M. Formato
Developmental Exposures To Pfas Mixtures Impair Elongation Of The Exocrine Pancreas In Zebrafish (Danio Rerio), Emily M. Formato
Masters Theses
Poly- and perfluoroalkyl substances (PFAS) are a class of bioaccumulative toxicants used in numerous industrial and commercial products. Perfluorooctanesulfonic acid (PFOS) alters pancreatic organogenesis during development, and perfluorohexanesulfonic acid (PFHxS) has been suggested as a replacement for PFOS due to its shorter carbon chain, but they are often found together in surfactants, such as legacy aqueous film-forming foam. This study investigates how developmental exposures to a PFAS mixture (PFHxS + PFOS) impact the developing exocrine pancreas. Zebrafish embryos (Tg(ptf1a:GFP)) were exposed to 0.01% DMSO, or 8, 16, 32 μM PFHxS alone, 16 μM PFOS alone, and 8, 16, and 32 …
Activation Of Nrf2 At Critical Windows Of Development Alters Protein S-Glutathionylation In The Zebrafish Embryo (Danio Rerio), Emily G. Severance
Activation Of Nrf2 At Critical Windows Of Development Alters Protein S-Glutathionylation In The Zebrafish Embryo (Danio Rerio), Emily G. Severance
Masters Theses
Perturbation of cellular redox homeostasis to a more oxidized state has been linked to adverse human health effects such as diabetes and cancer. However, the impact of altering the regulation of redox homeostasis during development is not fully understood. Specifically, this project investigates the role of the Nrf2 antioxidant response pathway and its effect on glutathione (GSH; cellular redox buffer) at critical windows of development. To explore this, we used zebrafish embryos (Danio rerio) as a model due to the function of GSH and the Nrf2 being conserved among vertebrates. We exposed zebrafish embryos to three Nrf2 activators: two antioxidant …
Investigating The Developmental Impacts Of 3,3’-Dichlorobiphenyl (Pcb-11) In Zebrafish (Danio Rerio), Monika A. Roy
Investigating The Developmental Impacts Of 3,3’-Dichlorobiphenyl (Pcb-11) In Zebrafish (Danio Rerio), Monika A. Roy
Doctoral Dissertations
The environmental pollutant 3,3’-dichlorobiphenyl (PCB-11) is a lower-chlorinated polychlorinated biphenyl (PCB) congener present in air and water samples. Both PCB-11 and its metabolite, 4-PCB-11-Sulfate, are detected in humans, including in pregnant women. The work conducted for this dissertation takes a developmental toxicology approach and uses zebrafish (Danio rerio) to investigate PCB-11’s potential impacts to the liver and pancreas. Chapter 1 introduces PCBs and the current knowledge gaps. Chapter 2 investigates PCB-11 interactions in short-term 4-day exposures with the Aryl hydrocarbon receptor (Ahr) pathway in both 0-20 mM individual and mixture exposures with other Ahr agonists. In Chapter 3, …
Hedgehog Signaling (Hh/Gli) Regulates Neurogenesis In The Zebrafish Hypothalamus, Ira Male
Hedgehog Signaling (Hh/Gli) Regulates Neurogenesis In The Zebrafish Hypothalamus, Ira Male
Doctoral Dissertations
The hypothalamus is the central regulator of a diverse homeostatic processes that are essential for the survival of the animal. Recently, the hypothalamus has been shown to be a neurogenic zone in many animal species including mice, zebrafish, sheep and potentially even humans with hypothalamic neurogenesis implicated in energy metabolism, stress, anxiety and reproduction. However, the identification of the cellular components and the signaling mechanisms regulating hypothalamic neurogenesis are only beginning to be elucidated. My dissertation research elucidates the role of Hh signaling in regulating hypothalamic neurogenesis throughout life. The first chapter of the dissertation offers a survey into the …
Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel
Masters Theses
In order to ascertain the degree of compatibility in developmental restructuring and behavioral plasticity between two fish species frequently made subject of laboratory research (Metriaclima zebra & Danio rerio), alternative trophic niche exposure experiments utilizing novel three-prong feeding treatments were conducted to obtain morphometric data, which demonstrated both species do bear some degree of plasticity. The results are somewhat complicated by differences in locality of detectable restructuring, which may be due to disparity in the form-function relationship for each species’ lineage. Each is notable in the manner of respective species’ jaw protrusion, as it is driven by anterior …
Partial Craniofacial Cartilage Rescue In Ace/Fgf8 Mutants From Compensatory Signaling From The Ventricle Of Danio Rerio, Douglas A. Calenda Ii
Partial Craniofacial Cartilage Rescue In Ace/Fgf8 Mutants From Compensatory Signaling From The Ventricle Of Danio Rerio, Douglas A. Calenda Ii
Masters Theses
Examples of asymmetric organs are found throughout the animal kingdom. Whether it is superficial like the fiddler crab’s claw or within an organism like our visceral organs, asymmetries have repeatedly evolved in nature. However, the genetic and developmental origins for asymmetric organ development remain unclear, especially for superficially paired structures. Within zebrafish, a striking example of asymmetry occurs within the ace/fgf8 mutant. The pharyngeal cartilages of these mutants develop asymmetrically 35% of the time, with more cartilages developing on the left or right side of the head, but the origins of this asymmetry are unknown. A significant proportion of mutants …
An Adult Zebrafish Brain Atlas To Investigate Shh Mediated Cell-Cell Signaling In Neurogenic Zones, Alyssa P. Lutservitz
An Adult Zebrafish Brain Atlas To Investigate Shh Mediated Cell-Cell Signaling In Neurogenic Zones, Alyssa P. Lutservitz
Masters Theses
Adult neurogenesis occurs in proliferative zones of the brain that contain neural progenitor cell populations capable of differentiating into specific cell types. However, we remain limited in our understanding of the signals that regulate neural progenitor cell proliferation and differentiation in adults. Recently zebrafish (Danio rerio) have emerged as an excellent model for studying the molecular mechanisms behind adult neurogenesis, because sixteen proliferative zones remain active in the adult brains. Thousands of fluorescent transgenic reporter lines have been generated in zebrafish that reveal gene expression patterns of cell-cell signaling systems, some of which may regulate neurogenesis in these …
How To Build A Spinal Cord: Exploring Radial Glial Proliferation And Their Contribution To Embryonic Neurogenesis, Kimberly A. Johnson
How To Build A Spinal Cord: Exploring Radial Glial Proliferation And Their Contribution To Embryonic Neurogenesis, Kimberly A. Johnson
Doctoral Dissertations
During embryonic neural development, the concerted actions of neural stem cells (NSCs) populate and pattern the tissues that will give rise to the brain and spinal cord. This heterogeneous NSC population initially consists of neuroepithelial cells, which will generate the first neurons present in the central nervous system (CNS) prior to transitioning into radial glial cells. Classically, radial glial cells are known to play a wide range of roles during CNS development, from maintaining neuronal homeostasis, as a scaffold for neuronal migration, and as a permissive growth substrate for directed axon pathfinding. Recently, radial glial cells have been proposed to …
Identification And Functional Characterization Of The Zebrafish Gene Quetschkommode (Que), Timo Friedrich
Identification And Functional Characterization Of The Zebrafish Gene Quetschkommode (Que), Timo Friedrich
Open Access Dissertations
Locomotion in vertebrates depends on proper formation and maintenance of neuronal networks in the hind-brain and spinal cord. Malformation or loss of factors required for proper maintenance of these networks can lead to severe neurodegenerative diseases limiting or preventing locomotion. A powerful tool to investigate the genetic and cellular requirements for development and/or maintenance of these networks is a collection of zebrafish mutants with defects in motility. The zebrafish mutant quetschkommode (que) harbors a previously unknown gene defect leading to abnormal locomotor behavior. Here I show that the que mutants display a seizure-like behavior starting around four days post fertilization …