Developmental Neuroscience Commons^™

Formation, Organization, And Synaptic Properties Of Circuits Between Thalamic Reticular Nucleus And Dorsal Lateral Geniculate Nucleus., Peter W. Campbell

Electronic Theses and Dissertations

The thalamic reticular nucleus (TRN) is an interface between thalamus and cortex that regulates thalamocortical rhythms and modulates sensory processing. Thalamocortical axon collaterals provide feedforward excitatory input onto GABAergic TRN neurons, which in turn convey feedback inhibition to dorsal thalamus. Here we used the mouse visual system to study the organization, pattern of innervation and functional responses between TRN and the dorsal lateral geniculate nucleus (dLGN). We used genetically modified mice to target components of this feedback loop (feedforward: CRH-Cre; feedback: GAD65 or SST-Cre) and we created Math 5^-/- strains to examine the impact of visual deaffrentation in these …

Sedative And Neurotoxic Properties Of Brexanolone Compared To Midazolam In The Developing Rodent Brain, Jacob Huffman

Dissertations

The developing brain is susceptible to extensive neurotoxicity following exposure to sedative/anesthetic drugs (SADs). Every year hundreds of thousands of children around the world are exposed to SADs with no viable non-neurotoxic agents approved for clinical use. Allopregnanolone (AlloP) has well-established sedative effects in adults and neonates. AlloP and many SADs produce sedation/anesthesia through allosteric modulation of GABA_A receptors, which is one of two principal mechanisms behind SAD-induced neurotoxicity. Evidence suggests AlloP has the unique capacity to regulate key apoptotic factors in adults and is widely involved with critical stages of neurodevelopment, indicating this neurosteroid might serve as a …

Developing Tadpoles Exhibit Metabolic And Organ Size Plasticity In Competitive Rearing Environments, Emma Kimberly

Undergraduate Honors Thesis Projects

Abstract

Plasticity is the ability of an organism to respond to environmental variation by expressing different phenotypes. In Red-eyed treefrog tadpoles, Agalychnis callidryas, competitive environments induce long guts and short tails. Despite having a larger gut, tadpoles reared with competition do not increase intake when food becomes available. Pilot data suggest that this is because they have lower metabolic rates. The ability to maintain a larger gut with a depressed metabolic rate is confusing because guts are energetically expensive, and suggests that another energetic trade-off is taking place. The purpose of this study was to investigate the effect of …

Effect Of Reduced Neurogenesis On Microglial Activation, Amelia Smith

Honors Scholars Collaborative Projects

The geriatric population of America has grown exponentially in the past century. Health degradations and expensive medical care are characteristic of this population with many of these costs due to age-related cognitive decline. It is essential to completely understand the mechanisms of normal and abnormal aging in the search for treatments for cognitive decline. A reduction of neurogenesis is a common factor in aging, but this reduction is even more drastic in individuals experiencing cognitive decline. It is unclear what effect reduced neurogenesis has on the extracellular environment, including glial cells. In particular, changes in microglial activation could be related …

The Effect Of Physical Activity And S-Equol On Neurogenesis In The Hiv-1 Transgenic Rat, Jeremy M. Lapointe

Senior Theses

The aim of this thesis is to investigate the effect of physical activity and the administration of s-equol on rates of neurogenesis in HIV-1 transgenic rats. HIV-1 is a neurodegenerative disease that leads to the wide range of cognitive impairment described as HAND. Neurogenesis is a newly discovered process that involves the birth of new neurons during our adult life within the dentate gyrus of the hippocampus. Therefore, inducing neurogenesis may be a proper therapeutic that can mitigate some of the cognitive destruction seen as a result of HIV-1 infection. Physical activity has shown to increase the rate of neurogenesis …

Transcutaneous Auricular Vagus Nerve Stimulation-Paired Rehabilitation For Oromotor Feeding Problems In Newborns: An Open-Label Pilot Study, Bashar W. Badran, Dorothea D. Jenkins, Daniel Cook, Sean Thompson, Morgan Darcy, William H. Devries, Georgia Mappin, Philipp Summers, Marom Bikson, Mark S. George

Publications and Research

Neonates born premature or who suffer brain injury at birth often have oral feeding dysfunction and do not meet oral intake requirements needed for discharge. Low oral intake volumes result in extended stays in the hospital (>2 months) and can lead to surgical implant and explant of a gastrostomy tube (G-tube). Prior work suggests pairing vagus nerve stimulation (VNS) with motor activity accelerates functional improvements after stroke, and transcutaneous auricular VNS (taVNS) has emerged as promising noninvasive form of VNS. Pairing taVNS with bottle-feeding rehabilitation may improve oromotor coordination and lead to improved oral intake volumes, ultimately avoiding the …

Pornography: Adolescent Brain Development & Addiction, William K. Canady

National Youth Advocacy & Resilience Conference

This presentation will explain the historical development of pornography. It will highlight three segments: 1- Porn’s impact on brain development of reward pathways, ultimately increasing the appetite for more porn. 2- Porn can be a false substitute for real intimacy, resulting in decreased sexual satisfaction with a real person and increased verbal and physical aggression. 3- Porn promotes sex trafficking, promotes multiple sex partners and reduced STD prevention.

Effects Of Novel Tool Use: Cortical And Functional Measures In Children Using A Prosthetic Simulator, Chris Copeland

UNO Student Research and Creative Activity Fair

As of 2005, there were a total of 1.6 million people living with the loss of a limb, with this population projected to double to 3.6 million by 2050 [1]. While prostheses aim to enhance the function of these individuals, it is estimated that 45% of pediatric prosthetic users reject their prosthesis [2]. The literature which describes the neurological control mechanisms of prosthetic use is sparse and often low-powered due to an inadequate number of participants. However, prosthetic simulators may be a solution to chronically low-powered prosthetic-centric studies by serving as functional homologues, though this has yet to be tested. …

Antagonistic Regulation Of Circadian Output And Synaptic Development By Jetlag And The Dyschronic-Slowpoke Complex, Angelique Lamaze, James E.C. Jepson, Oghenerukevwe Akpoghiran, Kyunghee Koh

Department of Neuroscience Faculty Papers

Circadian output genes act downstream of the clock to promote rhythmic changes in behavior and physiology, yet their molecular and cellular functions are not well understood. Here we characterize an interaction between regulators of circadian entrainment, output, and synaptic development in Drosophila that influences clock-driven anticipatory increases in morning and evening activity. We previously showed the JETLAG (JET) E3 ubiquitin ligase resets the clock upon light exposure, whereas the PDZ protein DYSCHRONIC (DYSC) regulates circadian locomotor output and synaptic development. Surprisingly, we find that JET and DYSC antagonistically regulate synaptic development at the larval neuromuscular junction, and reduced JET activity …

Neurodevelopment Outcome Of Neonates Treated With Intraventricular Colistin For Ventriculitis Caused By Multiple Drug-Resistant Pathogens-A Case Series, Kashif Hussain, Muhammad Sohail Salat, Gul Ambreen, Javaid Iqbal

Department of Biological & Biomedical Sciences

Background: Multiple-drug-resistant Gram-negative bacteria (MDR-GNB)-associated neonatal ventriculitis is a life-threatening complication that needs timely diagnosis and effective treatment with broad-spectrum antimicrobials in critical-care settings. Inadequate penetration of antibiotics through the blood-brain barrier also demands an intraventricular (IVT) route of administration. This study reports mortality and neurodevelopmental sequelae of neonates till 18 months of age, who received IVT-colistin for treating MDR-GNB associated ventriculitis.
Methods: In a case series of seven neonates with ventriculitis due to MDR-GNB at NICU of Aga Khan University Hospital, Pakistan, between June 2015 and 2018, we reviewed IVT-colistin therapy in critically ill neonates. Treatment outcomes were assessed …

Cis-Regulatory Analysis Of Onecut1 Expression In Fate-Restricted Retinal Progenitor Cells, Sruti Patoori, Nathalie Jean-Charles, Ariana Gopal, Sacha Sulaiman, Sneha Gopal, Brian Wang, Benjamin Souferi, Mark Emerson

Publications and Research

Background: The vertebrate retina consists of six major classes of neuronal cells. During development, these cells are generated from a pool of multipotent retinal progenitor cells (RPCs) that express the gene Vsx2. Fate-restricted RPCs have recently been identified, with limited mitotic potential and cell fate possibilities compared to multipotent RPCs. One population of fate-restricted RPCs, marked by activity of the regulatory element ThrbCRM1, gives rise to both cone photoreceptors and horizontal cells. These cells do not express Vsx2, but co-express the transcription factors (TFs) Onecut1 and Otx2, which bind to ThrbCRM1. The components of the gene regulatory networks that control …

Assessing The Role Of Planar Cell Polarity Protein Ptk7 In Axon Pathfinding Of Spinal Commissural Neurons, Joseph Paul Miano

Theses and Dissertations

Axon pathfinding is a fundamental step that establishes the vast networks of the nervous system. Understanding this process is important because disruptions to these neural networks can impair quality of life. During axon pathfinding, an axon’s growth cone comes in contact with a variety of secreted chemotropic signaling cues that control growth cone behavior through activation of signal transduction pathways which cause changes to the cytoskeleton. One such pathway is the Planar Cell Polarity (PCP) signal transduction pathway that responds to gradients of non-canonical Wnt ligands. PCP has a well-known role in axon pathfinding, including axon pathfinding in the spinal …

Focal Augmentation Of Somatostatin Interneuron Function And Subsequent Circuit Effects In Developmentally Malformed, Epileptogenic Cortex, Nicole Ekanem

Theses and Dissertations

Drug-resistant epilepsy (DRE) is a common clinical sequela of developmental cortical malformations such as polymicrogyria. Unfortunately, much remains unknown about the aberrant GABA-mediated circuit alterations that underlie DRE's onset and persistence in this context. To address this knowledge gap, we utilized the transcranial freeze lesion model in optogenetic mice lines (Somatostatin (SST)-Cre or Parvalbumin (PV)-Cre x floxed channelrhodopsin-2) to dissect features of the SST, PV, and pyramidal neuron microcircuit that are potentially associated with DRE. Investigations took place within developmental microgyria’s known pathological substrate, the adjoined and epileptogenic paramicrogyral region (PMR). As well, microcircuit relationships within the previously unexplored range …

Tissue-Specific Regulation Of Pnmt By Intron Retention During Neural Development, Meeti Mehta

Digital Repository: Showcase of Undergraduate Research Excellence

No abstract provided.

Characterizing The Requirements For The Matricellular Protein, Dccn, In Nervous System Function, Elizabeth L. Catudio Garrett

Graduate Student Theses, Dissertations, & Professional Papers

The brain is organized as a complex network of specialized neurons that communicate via a combination of electrical and chemical signals. Our brains function to generate movement, control organ function, or direct complex behaviors; all of which requires the ability to regulate the flow of communication between circuits and networks. Work in this thesis addresses two areas of neuron communication: first, how does the release of more than one neurotransmitter from a single neuron impact behavior, and second, are matricellular proteins (MCPs) key contributors to synaptic transmission and neuron function? The conserved CCN family of MCPs have a …

C-Jun Nh2-Terminal Kinase Signaling Controls Cellular Mechanisms Of Guided Cortical Interneuron Migration, Skye Eleanor Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

The cerebral cortex is an intricately organized brain structure responsible for high-level functions including sensory perception, movement, memory, language, and cognition. During corticogenesis, cortical excitatory neurons and inhibitory interneurons migrate from their respective progenitor zones into the developing cerebral cortex, deposit in the correct cortical layer, and establish connections with their appropriate synaptic partners. The balance between excitation and inhibition is critical for cortical circuitry development and function. Aberrant migration of inhibitory interneurons can alter the formation of cortical circuitry and lead to several neurodevelopmental disorders including epilepsy, autism spectrum disorder, and schizophrenia. Therefore, elucidating the mechanisms responsible for inhibitory …

Impact Of A Multimodal Exercise Program On Tibial Bone Health In Adolescents With Development Coordination Disorder: An Examination Of Feasibility And Potential Efficacy, Jocelyn L. Tan, Aris Siafarikas, Timo Rantalainen, Nicolas H. Hart, Fleur Mcintyre, Beth Hands, Paola Chivers

Research outputs 2014 to 2021

© 2020, International Society of Musculoskeletal and Neuronal Interactions. All rights reserved. Objectives: Developmental coordination disorder (DCD) compromises bone health purportedly due to lower levels of physical activity. The potential of an exercise intervention to improve bone health parameters in adolescents with DCD has not previously been studied. This study thus aimed to determine the impact of a multimodal exercise intervention on bone health in this population at-risk of secondary osteoporosis. Methods: Twenty-eight adolescents (17 male, 11 female) aged between 12-17 years (Mage =14.1) with DCD participated in a twice weekly, 13-week generalised multimodal exercise intervention. Peripheral quantitative computed tomography …

Effects Of Gestational Ozone Exposure On Privileged Placental And Brain Barrier Integrity, Alexander I. Hamm

Theses and Dissertations

Ambient outdoor ozone, a common of component of photochemical smog and urban air pollution, is linked to various neurological and vascular pathologies. Its immediate reaction with lung surfactant after inhalation results in complete reactivity of the gas, with no active ozone passing into circulation. This indicates the presence of secondary and tertiary mediators in ozone-related systemic pathologies after pulmonary insult. In vasculature, ozone exposure is associated with an acute hypertensive phenotype apparent at least 24 hours after dose, such as experienced on a hot summer afternoon in a large metropolitan area like Los Angeles or Mexico City. However, the effects …

Cholesterol Biosynthesis In The Nervous System With An Emphasis On Desmosterolosis, Luke Allen

Theses & Dissertations

Cholesterol biosynthesis is integral to proper neurodevelopment due to the reliance on de novo synthesis of cholesterol in the brain. Disruptions in this process have devastating outcomes for human life characterized by several phenotypic manifestations concomitant with developmental delay. The cholesterol biosynthesis disorder desmosterolosis is an extremely rare disorder with a severe clinical phenotype, however, the models used to study this disease are not well characterized. In addition to genetic disruptions in cholesterol biosynthesis, pharmacological perturbation is an understudied side effect of many commonly prescribed drugs. Here we present a characterization of the sterol profile of the mouse model of …

A Novel Switch-Like Function Of Delta-Catenin In Dendrite Development, Ryan Baumert

Dissertations and Theses (Open Access)

The formation of neuronal networks in the brain is tightly regulated, and dependent on the morphology of dendrites, the branch-like signal-receiving structures extending from neurons. Disruptions in dendrite development, or dendritogenesis, can lead to the atypical neuronal connectivity associated with multiple neurodevelopmental diseases. My research addresses molecular processes that underlie dendritogenesis via analysis of a pair of novel interactions involving the protein delta-catenin.

In neurons, delta-catenin localizes to dendrites and synapses, where it functions in their development and maintenance. Structurally, delta-catenin possesses a central Armadillo domain and a C-terminal PDZ-binding motif. This motif associates with PDZ domain-containing proteins, and is …