Neurosciences Commons^™

Mechanism Of Acetylcholinesterase's Neurotrophic Action On Drg Neurons Of Rat, Naga Venkata Pavan Kumar Kunala

Student Theses and Dissertations

The fundamental role of enzyme acetylcholinesterase (AChE) is to catalyze the neurotransmitter acetylcholine at cholinergic synapses. In addition to its catalytic activity, AChE appears to play a significant non-catalytic role of neurotropic activity on dorsal root ganglion (DRG) neurons of rat. However the mechanism responsible for AChE's neurotrophic activity is not fully understood. Earlier experiments in Dr. Srivatsan's laboratory demonstrated the binding of fluorophore conjugated AChE to cell surface of DRG neurons. These findings led to my hypothesis that AChE may bind to cell surface protein(s) in DRG neurons, and the resulting protein-protein interaction is responsible for activating downstream signaling …

Age Dependent Spatial Characteristics Of Epileptiform Activity In Malformed Cortex, L. Andrew Bell

Theses and Dissertations

Developmental cortical malformations are a major cause of intractable seizures. Determining the location and timing of susceptibility for epileptiform activity is critical to identifying what mechanisms contribute to epileptogenesis in any model. Using the freeze lesion rat model of polymicrogyria, we have identified, in lesioned cortex, these two aspects of epileptogenesis. Previous studies have demonstrated that epileptiform activity cannot be evoked prior to postnatal day (P) 12, but the malformed cortex is more susceptible to seizures as early as P10. An increase in excitatory afferents to the epileptogenic zone occurs before the onset of network epileptiform activity. Whether or not …

Specific Contributions Of Ventromedial, Anterior Cingulate, And Lateral Prefrontal Cortex For Attentional Selection And Stimulus Valuation., Daniel Kaping, Martin Vinck, R Matthew Hutchison, Stefan Everling, Thilo Womelsdorf

Brain and Mind Institute Researchers' Publications

Attentional control ensures that neuronal processes prioritize the most relevant stimulus in a given environment. Controlling which stimulus is attended thus originates from neurons encoding the relevance of stimuli, i.e. their expected value, in hand with neurons encoding contextual information about stimulus locations, features, and rules that guide the conditional allocation of attention. Here, we examined how these distinct processes are encoded and integrated in macaque prefrontal cortex (PFC) by mapping their functional topographies at the time of attentional stimulus selection. We find confined clusters of neurons in ventromedial PFC (vmPFC) that predominantly convey stimulus valuation information during attention shifts. …

Empathy-Based Conservation: An Interdisciplinary Approach To Conservation Policy And Decision-Making, Kaitlyn Delashmutt

Department of Environmental Studies: Undergraduate Student Theses

In the late 20^th century, neuroscientists in Italy discovered a neuron in the brain capable of mentally mimicking the emotions derived from the actions of others (Rizzolatti and Craighero, 2004). It is the process that makes your elbow ache when someone else knocks their elbow on the counter or the uncontrollable smile that creeps up when someone smiles at you. No questions asked, people intuitively sense what others are feeling. The old school of thought was that humans deduced through logic and reason the actions of others and interpreted the emotions through a rational process (Carew et al, 2008). …

A Diffusion Tensor Imaging Software Comparison And Between Control Subjects And Subjects With Known Anatomical Diagnosis, Michael C. Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diffusion weighted imaging (DWI) is a magnetic resonance imaging (MRI) method that produces in vivo images of biological tissues weighted with the local micro-structural characteristics of water diffusion. Diffusion tensor imaging (DTI), a form of DWI, is useful when a tissue, such as the neural axons of white matter in the brain, has an internal fibrous structure that allows water to diffuse more rapidly in alignment with the fibers. Changes in the water diffusion pattern indicate changes in the fiber structure which can result from damage to the fibers. Measurements of the water diffusion patterns include overall diffusivity, Apparent Diffusion …

The Effects Of Pten Deletion On Cell Size And Plasticity In The Hippocampus, Margaret Sperow

Theses and Dissertations (ETD)

The tumor suppressor phosphatase and tensin homolog (PTEN) is the central negative regulator of the phosphatidylinositol 3-kinase (PI3K) -signaling pathway, which mediates diverse processes in various tissues. In the nervous system, the PI3K pathway modulates proliferation, migration, cellular size and synaptic transmission and plasticity. Neurologic abnormalities such as autism, seizures, and ataxia are associated with inherited PTEN mutations. Yet, how PTEN loss contributes to neurologic dysfunction remains unknown. PTEN loss during early development is associated with extensive deficits in neuronal migration and substantial hypotrophy of neurons and synaptic densities. However, whether its effect on synaptic transmission and plasticity is direct …

Paradoxical Reversal Learning Enhancement By Stress Or Prefrontal Cortical Damage: Rescue With Bdnf., Carolyn Graybeal, Michael Feyder, Emily Schulman, Lisa M Saksida, Timothy J Bussey, Jonathan L Brigman, Andrew Holmes

Brain and Mind Institute Researchers' Publications

Stress affects various forms of cognition. We found that moderate stress enhanced late reversal learning in a mouse touchscreen-based choice task. Ventromedial prefrontal cortex (vmPFC) lesions mimicked the effect of stress, whereas orbitofrontal and dorsolateral striatal lesions impaired reversal. Stress facilitation of reversal was prevented by BDNF infusion into the vmPFC. These findings suggest a mechanism by which stress-induced vmPFC dysfunction disinhibits learning by alternate (for example, striatal) systems.

Principles Of Sensorimotor Learning., Daniel M Wolpert, Jörn Diedrichsen, J Randall Flanagan

Brain and Mind Institute Researchers' Publications

The exploits of Martina Navratilova and Roger Federer represent the pinnacle of motor learning. However, when considering the range and complexity of the processes that are involved in motor learning, even the mere mortals among us exhibit abilities that are impressive. We exercise these abilities when taking up new activities - whether it is snowboarding or ballroom dancing - but also engage in substantial motor learning on a daily basis as we adapt to changes in our environment, manipulate new objects and refine existing skills. Here we review recent research in human motor learning with an emphasis on the computational …

Human Glial-Restricted Progenitor Transplantation Into Cervical Spinal Cord Of The Sod1 Mouse Model Of Als., Angelo C Lepore, John O'Donnell, Andrew S Kim, Timothy Williams, Alicia Tuteja, Mahendra S Rao, Linda L Kelley, James T Campanelli, Nicholas J Maragakis

Department of Neuroscience Faculty Papers

Cellular abnormalities are not limited to motor neurons in amyotrophic lateral sclerosis (ALS). There are numerous observations of astrocyte dysfunction in both humans with ALS and in SOD1(G93A) rodents, a widely studied ALS model. The present study therapeutically targeted astrocyte replacement in this model via transplantation of human Glial-Restricted Progenitors (hGRPs), lineage-restricted progenitors derived from human fetal neural tissue. Our previous findings demonstrated that transplantation of rodent-derived GRPs into cervical spinal cord ventral gray matter (in order to target therapy to diaphragmatic function) resulted in therapeutic efficacy in the SOD1(G93A) rat. Those findings demonstrated the feasibility and efficacy of transplantation-based …

Investigation Of Spatio-Temporal Effects Of Fmri Visual Field Mapping Techniques On V1, John J. Janik

Dissertations (1934 -)

Blood oxygenation level dependent functional magnetic resonance imaging has been used extensively for mapping the representation of the visual field within the human brain. Visual field mapping using fMRI has been used clinically to assess patients with cortical pathology and to plan surgical treatment impacting the visual system. The accuracy of fMRI-based visual field mapping methods needs to be better understood for clinical use. This accuracy can be important for presurgical mapping of brain function near a tumor resection site since inaccurate rendition of the underlying neural function could lead to inappropriate resection of viable brain tissue. The most widely …

The Characterization Of The Anterograde And Retrograde Consequences Of Traumatic Axonal Injury In A Mouse Model Of Diffuse Brain Injury, John E. Greer

Theses and Dissertations

Traumatic axonal injury (TAI) is a consistent feature of (TBI) and is responsible for much of its associated morbidity. TAI is now recognized to result from progressive/secondary axonal injury, though much remains unknown in regards to the pathobiology and the long-term consequences of axonal injury. TAI has been described in the perisomatic domain, located within the neocortex following mild TBI, and within this domain has been linked to neuronal recovery, not neuronal cell death in the acute setting. Due to technical limitations, our understanding of the long-term fate of this neuronal population and the mechanisms responsible for permitting neuronal survival, …

Developmental Remodeling Of Relay Cells In The Dorsal Lateral Geniculate Nucleus (Dlgn) Of The Mouse And The Role Of Retinal Innervation, Rana El-Danaf

Theses and Dissertations

The dorsal lateral geniculate nucleus (dLGN) has become an important model for studying many aspects of visual system development. To date, studies have focused on the development of retinal projections and the role of activity in shaping the pattern of synaptic connections made with thalamocortical relay cells. By contrast, little is known about relay cells and the factors that regulate the growth and establishment of their dendritic architecture. In many systems, such growth seems consistent with the synaptotrophic hypothesis which states that synapse formation and dendritic growth work in a concerted fashion such that afferent input and the establishment of …

Lateralization Of Emotion, Reaction Time, And Skin Conductance Responsiveness, Kimberley Erin Rose

Loma Linda University Electronic Theses, Dissertations & Projects

Bilateral presentations of brief (250 ms), unmasked emotional and neutral stimuli were examined in two experiments with primarily female samples. Reaction time and accuracy data were used to measure perception of emotion and skin conductance response (SCR) was used to measure experience of emotion. Both words and pictures were used to account for hemispheric differences in language and visuospatial dominance. Response time was faster to emotional pictures than words. Reaction time and speeded accuracy data did not support right hemisphere hypothesis (RHH) or valence hypothesis (VH) in the expected manner. Data suggested emotion caused greater interference under speeded conditions in …

A Single Phenylalanine Residue In The Main Intracellular Loop Of Α1 Γ-Aminobutyric Acid Type A And Glycine Receptors Influences Their Sensitivity To Propofol, Gustavo Moraga-Cid, Gonzalo E. Yevenes, Günther Schmalzing, Robert W. Peoples, Luis G. Aguayo

Biomedical Sciences Faculty Research and Publications

Background: The intravenous anesthetic propofol acts as a positive allosteric modulator of glycine (GlyRs) and γ-aminobutyric acid type A (GABA_ARs) receptors. Although the role of transmembrane residues is recognized, little is known about the involvement of other regions in the modulatory effects of propofol. Therefore, the influence of the large intracellular loop in propofol sensitivity of both receptors was explored. Methods: The large intracellular loop of α₁ GlyRs and α₁β₂ GABA_ARs was screened using alanine replacement. Sensitivity to propofol was studied using patch-clamp recording in HEK293 cells transiently transfected with …

Spiking Patterns And Their Functional Implications In The Antennal Lobe Of The Tobacco Hornworm Manduca Sexta, Hong Lei, Carolina E. Reisenman, Caroline H. Wilson, Prasad Gabbur, John G. Hildebrand

Health Sciences and Kinesiology Faculty Articles

Bursting as well as tonic firing patterns have been described in various sensory systems. In the olfactory system, spontaneous bursts have been observed in neurons distributed across several synaptic levels, from the periphery, to the olfactory bulb (OB) and to the olfactory cortex. Several in vitro studies indicate that spontaneous firing patterns may be viewed as “fingerprints” of different types of neurons that exhibit distinct functions in the OB. It is still not known, however, if and how neuronal burstiness is correlated with the coding of natural olfactory stimuli. We thus conducted an in vivo study to probe this question …

Uncertain Progress On The Fuzzy Boundaries Of Alzheimer's Disease: Reading Between The Guidelines, Peter J. Whitehouse

Faculty Scholarship

No abstract provided.

Slob, A Slowpoke Channel Binding Protein, Regulates Insulin Pathway Signaling And Metabolism In Drosophila., Amanda L. Sheldon, Jiaming Zhang, Hong Fei, Irwin B Levitan

Department of Neuroscience Faculty Papers

There is ample evidence that ion channel modulation by accessory proteins within a macromolecular complex can regulate channel activity and thereby impact neuronal excitability. However, the downstream consequences of ion channel modulation remain largely undetermined. The Drosophila melanogaster large conductance calcium-activated potassium channel SLOWPOKE (SLO) undergoes modulation via its binding partner SLO-binding protein (SLOB). Regulation of SLO by SLOB influences the voltage dependence of SLO activation and modulates synaptic transmission. SLO and SLOB are expressed especially prominently in median neurosecretory cells (mNSCs) in the pars intercerebralis (PI) region of the brain; these cells also express and secrete Drosophila insulin like …

Brain Activation And Connectivity In Non-Disabled Multiple Sclerosis Patients, Rene A. Colorado

Dissertations and Theses (Open Access)

Multiple sclerosis (MS) is the most common demyelinating disease affecting the central nervous system. There is no cure for MS and current therapies have limited efficacy. While the majority of individuals with MS develop significant clinical disability, a subset experiences a disease course with minimal impairment even in the presence of significant apparent tissue damage on magnetic resonance imaging (MRI). The current studies combined functional MRI and diffusion tensor imaging (DTI) to elucidate brain mechanisms associated with lack of clinical disability in patients with MS. Recent evidence has implicated cortical reorganization as a mechanism to limit the clinical manifestation of …

The Role Of The Androgen Receptor Cofactor P44/Wdr77 In Astrocyte Activation, Bryce H. Vincent

Dissertations and Theses (Open Access)

Astrogliosis is induced by neuronal damage and is also a pathological feature of the major aging-related neurodegenerative disorders. The mechanisms that control the cascade of astrogliosis have not been well established. In a previous study, we identified a novel androgen receptor (AR)-interacting protein (p44/WDR77) and found that it plays a critical role in the control of proliferation and differentiation of prostate epithelial cells. In the present study, we found that deletion of the p44 gene in the mouse brain caused accelerated aging with dramatic astrogliosis. The p44/WDR77 is expressed in astrocytes and loss of p44/WDR77 expression in astrocytes leads to …

Augmented Cocaine Seeking In Response To Stress Or Crf Delivered Into The Ventral Tegmental Area Following Long-Access Self-Administration Is Mediated By Crf Receptor Type 1 But Not Crf Receptor Type 2, Jordan M. Blacktop, Chad Seubert, David A. Baker, Nathan Ferda, Geng Lee, Evan N. Graf, John R. Mantsch

Biomedical Sciences Faculty Research and Publications

Stressful events are determinants of relapse in recovering cocaine addicts. Excessive cocaine use may increase susceptibility to stressor-induced relapse through alterations in brain corticotropin-releasing factor (CRF) regulation of neurocircuitry involved in drug seeking. We previously reported that the reinstatement of cocaine seeking by a stressor (footshock) is CRF dependent and is augmented in rats that self-administered cocaine under long-access (LgA; 6 h daily) conditions for 14 d when compared with rats provided shorter daily cocaine access [short access (ShA) rats; 2 h daily]. Further, we have demonstrated that reinstatement in response to intracerebroventricular CRF administration is heightened in LgA rats. …

Natural And Synthetic Corticosteroids Inhibit Uptake2-Mediated Transport In Cns Neurons, Jonathan E. Hill, Khadijah Makky, Lalita Shrestha, Cecilia J. Hillard, Paul J. Gasser

Biomedical Sciences Faculty Research and Publications

In addition to exerting actions via mineralocorticoid and glucocorticoid receptors, corticosteroids also act by inhibiting uptake₂, a high-capacity monoamine transport system originally described in peripheral tissues. Recent studies have demonstrated that uptake₂ transporters are expressed in the brain and play roles in monoamine clearance, suggesting that they mediate some corticosteroid effects on physiological and behavioral processes. However, the sensitivity of brain uptake₂ to many natural and synthetic corticosteroids has not been characterized. Cultured rat cerebellar granule neurons (CGNs) were previously shown to exhibit corticosterone-sensitive accumulation of the uptake₂ substrate1-methyl-4-phenylpyridinium (MPP⁺). We examined the …

The Levels Of Analysis Revisited., Scott A Macdougall-Shackleton

Brain and Mind Institute Researchers' Publications

The term levels of analysis has been used in several ways: to distinguish between ultimate and proximate levels, to categorize different kinds of research questions and to differentiate levels of reductionism. Because questions regarding ultimate function and proximate mechanisms are logically distinct, I suggest that distinguishing between these two levels is the best use of the term. Integrating across levels in research has potential risks, but many benefits. Consideration at one level can help generate novel hypotheses at the other, define categories of behaviour and set criteria that must be addressed. Taking an adaptationist stance thus strengthens research on proximate …

Network Modulation During Complex Syntactic Processing, Dirk B. Den Ouden, Dorothee Saur, Wolfgang Mader, Björn Schelter, Sladjana Lukic, Eisha Wali, Jens Timmer, Cynthia K. Thompson

Communication Sciences and Disorders Faculty Articles and Research

Complex sentence processing is supported by a left-lateralized neural network including inferior frontal cortex and posterior superior temporal cortex. This study investigates the pattern of connectivity and information flow within this network. We used fMRI BOLD data derived from 12 healthy participants reported in an earlier study (Thompson, C. K., Den Ouden, D. B., Bonakdarpour, B., Garibaldi, K., & Parrish, T. B. (2010b). Neural plasticity and treatment-induced recovery of sentence processing in agrammatism. Neuropsychologia, 48(11), 3211–3227) to identify activation peaks associated with object-cleft over syntactically less complex subject-cleft processing. Directed Partial Correlation Analysis was conducted on time series …

Upregulation Of Cathepsin D In The Caudate Nucleus Of Primates With Experimental Parkinsonism., Sowmya V. Yelamanchili, Amrita Datta Chaudhuri, Claudia T. Flynn, Howard S. Fox

Journal Articles: Pharmacology & Experimental Neuroscience

BACKGROUND: In Parkinson's disease there is progressive loss of dopamine containing neurons in the substantia nigra pars compacta. The neuronal damage is not limited to the substantia nigra but progresses to other regions of brain, leading to loss of motor control as well as cognitive abnormalities. The purpose of this study was to examine causes of progressive damage in the caudate nucleus, which plays a major role in motor coordination and cognition, in experimental Parkinson's disease.

RESULTS: Using chronic 1-methyl-4phenyl-1,2,3,6-tetrahydropyridine treatment of rhesus monkeys to model Parkinson's disease, we found a upregulation of Cathepsin D, a lysosomal aspartic protease, in …

Emotional Reactivity And Regulation In Current And Remitted Depression: An Event Related Potential Study, Lauren M. Bylsma

USF Tampa Graduate Theses and Dissertations

Major Depressive Disorder (MDD) is thought to be characterized by emotion regulation deficits, including decreased use of adaptive strategies such as reappraisal, but little is known about the exact nature of these deficits and whether or not they are specific to the depressed mood state. The late positive potential (LPP) is a sustained positive deflection of the event-related potential (ERP) associated with responding to emotionally-valenced stimuli, and reappraisal strategies have been found to reduce LPP magnitude in response to emotional stimuli in healthy individuals, but this effect has not been examined in MDD. This study utilized ERPs to examine emotional …

Prevalencia Del Virus De La Diarrea Viral Bovina Y De Animales Portadores Del Virus En Bovinos En La Provincia De Espinar, Cusco., Cesar Cardenas A., Hermelinda G. Rivera, Mariluz Araínga, Mercy Ramirez V., Jimmy De Paz M.

Journal Articles: Pharmacology & Experimental Neuroscience

The prevalence of bovine viral diarrhea virus (BVDV) in 406 cattle was evaluated of both sexes and older than 6 months. Animals belonged to 114 small farmers from three rural communities of the province of Espinar, Cusco, Peru. Blood samples were collected according to three age groups Ɩ-12, 13-23, >24 months old). Serum samples were tested for antibodies against BVDV using the viral neutralization test. The 56.2 ± 4.8% 鴤/406) of samples had antibodies against BVDV. Persistently infected animals were not detected. Antibodies were present in the three age groups, but the highest prevalence ࿡.4%) was detected in animals older …

Insulin-Like Growth Factor 1 And Transforming Growth Factor-Β Stimulate Cystine/Glutamate Exchange Activity In Dental Pulp Cells, Katherine Pauly, Kymberly Fritz, Alyssa Furey, Doug Lobner

Biomedical Sciences Faculty Research and Publications

Introduction

The growth factors insulin-like growth factor (IGF-1) and transforming growth factor-β (TGF-β) are protective to dental pulp cells in culture against the toxicity of the composite materials Durafill VS and Flow Line (Henry Schein Inc, New York, NY). Because the toxicity of these materials is mediated by oxidative stress, it seemed possible that the protective effects of IGF-1 and TGF-β were through the enhancement of an endogenous antioxidant mechanism.

Methods

We used cultured dental pulp cells to determine the mechanism of the protective effects of IGF-1 and TGF-β, focusing on the glutathione system and the role of cystine/glutamate exchange …

Oral Administration Of Levo-Tetrahydropalmatine Attenuates Reinstatement Of Extinguished Cocaine Seeking By Cocaine, Stress Or Drug-Associated Cues In Rats, Yazmin Figueroa-Guzman, Christopher R. Mueller, Oliver Vranjkovic, Samantha Wisniewski, Zheng Yang, Shi-Jiang Li, Colin Bohr, Evan N. Graf, David A. Baker, John R. Mantsch

Biomedical Sciences Faculty Research and Publications

Cocaine addiction is characterized by a persistently heightened susceptibility to drug relapse. For this reason, the identification of medications that prevent drug relapse is a critical goal of drug abuse research. Drug re-exposure, the onset of stressful life events, and exposure to cues previously associated with drug use have been identified as determinants of relapse in humans and have been found to reinstate extinguished cocaine seeking in rats. This study examined the effects of acute oral (gavage) administration of levo-tetrahydropalmatine (l-THP), a tetrahydroprotoberberine isoquinoline with a pharmacological profile that includes antagonism of D1, D2 and D3 dopamine receptors, …

Treating Trauma Survivors With Neurofeedback: A Grounded Theory Study Based On The Practices Of Experienced Mental Health Professionals, Christine L. Currie

Counseling & Human Services Theses & Dissertations

Neuroscience, the mental health field, and the concept of trauma as an underlying factor in mental and physical disorders have been inextricably linked since the inception of the mental health professions. Numerous quantitative studies have indicated that neurofeedback may be effective in ameliorating trauma symptoms; however, there is a paucity of research exploring the factors that produce those positive outcomes. The purpose of this qualitative grounded theory study was to explore the factors and processes that influence treatment outcomes when neurofeedback is used with trauma survivors. Thirty interviews were completed with ten experienced mental health and neurofeedback professionals identified through …

Patterns Of Fetal Heart Rate Response At ∼30 Weeks Gestation Predict Size At Birth, C. Sandman, C. J. Cordova, E. P. Davis, Laura M. Glynn, C. Buss

Psychology Faculty Articles and Research

There is evidence that fetal exposure to maternal stress is associated with adverse birth outcomes. Less is known about the association between fetal responses to a stressor and indicators of fetal maturity and developmental outcomes. The purpose of the present study was to determine whether fetal heart rate (FHR) patterns in response to a startling stimulus at ∼30 weeks of gestation were associated with gestational age at birth and birth weight. FHR was measured in 156 maternal–fetal dyads following a vibroacoustic stimulus. All pregnancies were singleton intrauterine pregnancies in English-speaking women who were primarily married, middle class, White and at …