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Ethanol Exposure During Synaptogenesis In A Mouse Model Of Fetal Alcohol Spectrum Disorders: Acute And Long-Term Effects On Gene Expression And Behaviour, Morgan L. Kleiber

Electronic Thesis and Dissertation Repository

Alcohol is a neuroactive molecule that is able to exert variable and often detrimental effects on the developing brain, resulting in a broad range of physiological, behavioural, and cognitive phenotypes that characterize ‘fetal alcohol spectrum disorders’ (FASD). Factors affecting the manifestation of these phenotypes include alcohol dosage, timing of exposure, and pattern of maternal alcohol consumption; however, the biological processes that are vulnerable to ethanol at any given neurodevelopmental stage are unclear, as is how their disruption results in the emergence of specific pathological phenotypes later in life.

The research included in this thesis utilizes a C57BL/6J (B6) mouse model …

Microengineering The Neural Tube, Christopher Demers

Electronic Theses and Dissertations

Early embryonic development is a complex and highly regulated orchestra of instructive cues that collectively guide naïve stem cells towards progressively more specialized fates. In the neural tube, the precursor structure to the brain and spinal cord, these signals emanate from ‘organizing centers’ surrounding the neural tube. These organizing centers send out soluble cues or morphogens that diffuse tens to hundreds of microns to recipient cells residing in the neural tube. Re-creating this dynamic landscape of cues in vitro is impossible using standard cell culture tools and techniques. However, microfluidics is perfectly suited to fill this gap, allowing precise control …

The Neurophysiology Of Intersensory Selective Attention And Task Switching, Jeremy W. Murphy

Dissertations, Theses, and Capstone Projects

Our ability to selectively attend to certain aspects of the world and ignore others is fundamental to our day-to-day lives. The need for selective attention stems from capacity limitations inherent in our perceptual and cognitive processing architecture. Because not every elemental piece of our environment can be fully processed in parallel, the nervous system must prioritize processing. This prioritization is generally referred to as selective attention. Meanwhile, we are faced with a world that is constantly in flux, such that we have to frequently shift our attention from one piece of the environment to another and from one task to …

Evaluation Of The Developmental Toxicity Of Lead In The Danio Rerio Body, Nicole M. Roy, Sarah Dewolf, Bruno Carneiro

Biology Faculty Publications

Lead has been utilized throughout history and is widely distributed and mobilized globally. Although lead in the environment has been somewhat mitigated, the nature of lead and its extensive uses in the past prohibit it from being completely absent from our environment and exposure to lead is still a public health concern. Most studies regarding lead toxicity have focused on the brain. However, little is found in the literature on the effects of lead in other tissues. Here, we utilize the zebrafish model system to investigate effects of lead exposure during early developmental time windows at 24, 48 and 72 …

Temporal Localization Of Insulin-Like Growth Factor 1 (Igf1) Positive Cells In Developing Hypothyroid Brain, Shelby Anne Kline

All Graduate Theses, Dissertations, and Other Capstone Projects

Hypothyroidism has been known to result in numerous neuroanatomical defects in the developing brain. To investigate further into the mechanism in which these defects are obtained, local brain insulin-like growth factor 1 (Igf1) was investigated in relation to the hypothyroid brain. There are many similarities between hypothyroidism and the Igf1 deficient brain. Additionally, TH (thyroid hormone) is known to interact with Igf1. Therefore, the purpose of this study was to investigate the effect of induced congenital hypothyroidism on the temporal expression of Igf1-positive cells in the brain. To investigate the relationship between TH and Igf1 in the brain, we inhibited …

Dual Functions For Insulinoma-Associated 1 In Retinal Development, Marie A. Forbes-Osborne

Theses and Dissertations--Biology

Proper visual system function requires tightly controlled proliferation of a pool of relatively homogeneous retinal progenitor cells, followed by the stepwise specification and differentiation of multiple distinct cell types. These retinal cells, both neuronal and glial, must be generated in the correct numbers, and the correct laminar location to permit the formation of synaptic connections between individual cell types. After synapses are made, constant signaling is required as part of normal retinal function, and to maintain cellular identity and connectivity. These processes rely on both extrinsic and intrinsic signaling, with regulation of gene expression by cascades of transcription factors having …

Polychlorinated Biphenyl Exposure Alters Oxytocin Receptor Gene Expression And Maternal Behavior In Rat, Howard Cromwell

Howard Casey Cromwell

Polychlorinated biphenyl (PCB) is a persistent organic pollutant known to induce diverse molecular and behavioral alterations. Effects of PCB exposure could be transmitted to future generations via changes in behavior and gene expression. Previous work has shown that PCB-exposure can alter social behavior. The present study extends this work by examining a possible molecular mechanism for these changes. Pregnant rats (Sprague-Dawley) were exposed through diet to a combination of non-coplanar (PCB 47 - 2,20,4,40-tetrachlorobiphenyl) and coplanar (PCB 77 - 3,30,4,40- tetrachlorobiphenyl) congeners. Maternal care behaviors were examined by evaluating the rate and quality of nest building on the last 4 …