Neurosciences Commons^™

The Influence Of Competing Perceptual And Motor Priors In The Context Of The Size-Weight Illusion, Gavin Buckingham, Melvyn Goodale

Gavin Buckingham

When lifting objects of identical mass but different sizes, people perceive the smaller objects as weighing more than the larger ones (the 'size-weight' illusion, SWI). While individual's grip and load force rates are rapidly scaled to the objects' actual mass, the magnitude of the force used to lift these SWI-inducing objects is rarely discussed. Here, we show that participants continue to apply a greater loading force to a large SWI-inducing cube than to a small SWI cube, lift after lift. These differences in load force persisted long after initial errors in grip and load force rates had been corrected. Interestingly, …

Multiple Mechanisms Of Consciousness: The Neural Correlates Of Emotional Awareness., Jayna M Amting, Steven G Greening, Derek G V Mitchell

Brain and Mind Institute Researchers' Publications

Emotional stimuli, including facial expressions, are thought to gain rapid and privileged access to processing resources in the brain. Despite this access, we are conscious of only a fraction of the myriad of emotion-related cues we face everyday. It remains unclear, therefore, what the relationship is between activity in neural regions associated with emotional representation and the phenomenological experience of emotional awareness. We used functional magnetic resonance imaging and binocular rivalry to delineate the neural correlates of awareness of conflicting emotional expressions in humans. Behaviorally, fearful faces were significantly more likely to be perceived than disgusted or neutral faces. Functionally, …

Postulated Vasoactive Neuropeptide Immunopathology Affecting The Blood-Brain/Blood-Spinal Barrier In Certain Neuropsychiatric Fatigue-Related Conditions: A Role For Phosphodiesterase Inhibitors In Treatment?, Donald R. Staines, Ekua W. Brenu, Sonya Marshall-Gradisnik

Sonya Marshall-Gradisnik

Neuropsychiatric symptoms occur in a number of neurological fatigue-related conditions including multiple sclerosis (MS), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and chronic fatigue syndrome (CFS). These conditions have been attributed variably to neuroinfl ammatory and neurodegenerative processes. While autoimmune pathology, at least in part, has long been suspected in these conditions proof has been elusive. Autoimmune pathomechanisms affecting the blood–brain barrier (BBB) or blood–spinal barrier (BSB) may predispose the BBB/BSB to ‘leakiness’ and be a precursor to additional autoimmune events resulting in neuroinfl ammatory or neurodegenerative processes. The aim of the paper is to postulate immunopathology of the cerebrospinal …

Fenotipo Y Genotipo Del Virus De La Diarrea Viral Aislado De Bovinos En El Perú., Mariluz Araínga, Hermelinda Rivera G., Juan Carlos Huaman G., Alberto Manchego S.

Journal Articles: Pharmacology & Experimental Neuroscience

The aim of this study was to determine the phenotype and genotype of Bovine Viral Diarrhoea Virus (BVDV) in Peruvian cattle. During the period 1998-2007, tissues of aborted fetus, blood, serum or plasma samples of bovine with acute infection or persistently infected from dairy herds of various locations in the country were collected and the BVDV antigen was detected by immnunofluorescence or capture ELISA tests, and positive samples were inoculated en BVDV free BT cells and cultured until third passage to determine the biotype. Both animal tissues and third passage of positive samples were tested by a Real Time Reverse …

Deficits In Attention To Emotional Stimuli Distinguish Youth With Severe Mood Dysregulation From Youth With Bipolar Disorder., Brendan A Rich, Melissa A Brotman, Daniel P Dickstein, Derek G V Mitchell, R James R Blair, Ellen Leibenluft

Brain and Mind Institute Researchers' Publications

Studying attention in the context of emotional stimuli may aid in differentiating pediatric bipolar disorder (BD) from severe mood dysregulation (SMD). SMD is characterized by chronic irritability, arousal, and hyper-reactivity; SMD youth frequently receive a BD diagnosis although they do not meet DSM-IV criteria for BD because they lack manic episodes. We compared 57 BD (14.4 +/- 2.9 years old, 56% male), 41 SMD (12.6 +/- 2.6 years old, 66% male), and 33 control subjects (13.7 +/- 2.5 years old, 52% male) using the Emotional Interrupt task, which examines how attention is impacted by positive, negative, or neutral distracters. We …

Toxicity Of Flow Line, Durafill Vs, And Dycal To Dental Pulp Cells: Effects Of Growth Factors, Alyssa Furey, Julie Hjelmhaug, Doug Lobner

Biomedical Sciences Faculty Research and Publications

Introduction

The objective was to determine the effects of growth factor treatment on dental pulp cell sensitivity to toxicity of 2 composite restoration materials, Flow Line and Durafill VS, and a calcium hydroxide pulp capping material, Dycal.

Methods

Toxicity of the dental materials to cultures of primary dental pulp cells was determined by the MTT metabolism assay. The ability of 6 different growth factors to influence the toxicity was tested.

Results

A 24-hour exposure to either Flow Line or Durafill VS caused approximately 40% cell death, whereas Dycal exposure caused approximately 80% cell death. The toxicity of Flow Line and …

Synaptotoxicity Of Alzheimer Beta Amyloid Can Be Explained By Its Membrane Perforating Property, Fernando Sepulveda, Jorge Parodi, Robert W. Peoples, Carlos Opazo, Luis G. Aguayo

Biomedical Sciences Faculty Research and Publications

The mechanisms that induce Alzheimer’s disease (AD) are largely unknown thereby deterring the development of disease-modifying therapies. One working hypothesis of AD is that Aβ excess disrupts membranes causing pore formation leading to alterations in ionic homeostasis. However, it is largely unknown if this also occurs in native brain neuronal membranes. Here we show that similar to other pore forming toxins, Aβ induces perforation of neuronal membranes causing an increase in membrane conductance, intracellular calcium and ethidium bromide influx. These data reveal that the target of Aβ is not another membrane protein, but that Aβ itself is the cellular target …

Involvement Of Noradrenergic Neurotransmission In The Stress- But Not Cocaine-Induced Reinstatement Of Extinguished Cocaine-Induced Conditioned Place Preference In Mice: Role For Β-2 Adrenergic Receptors, John R. Mantsch, Andy Meyer, Oliver Vranjkovic, Chad E. Beyer, David A. Baker, Holly Caretta

Biomedical Sciences Faculty Research and Publications

The responsiveness of central noradrenergic systems to stressors and cocaine poses norepinephrine as a potential common mechanism through which drug re-exposure and stressful stimuli promote relapse. This study investigated the role of noradrenergic systems in the reinstatement of extinguished cocaine-induced conditioned place preference by cocaine and stress in male C57BL/6 mice. Cocaine- (15 mg/kg, i.p.) induced conditioned place preference was extinguished by repeated exposure to the apparatus in the absence of drug and reestablished by a cocaine challenge (15 mg/kg), exposure to a stressor (6-min forced swim (FS); 20–25°C water), or administration of the α-2 adrenergic receptor (AR) antagonists yohimbine …

On The Number Of Trials Necessary For Stabilization Of Error-Related Brain Activity Across The Life Span, Jason Themanson, Matthew Pontifex, Mark Scudder, Michael Brown, Kevin O'Leary, Chien-Ting Wu, Charles Hillman

Jason R. Themanson, Ph.D

The minimum number of trials necessary to accurately characterize the error-related negativity (ERN) and the error positivity (Pe) across the life span was investigated using samples of preadolescent children, college-age young adults, and older adults. Event-related potentials and task performance were subsequently measured during a modified flanker task. Response-locked averages were created using sequentially increasing errors of commission in blocks of two. Findings indicated that across all age cohorts ERN and Pe were not significantly different relative to the within-participants grand average after six trials. Further, results indicated that the ERN and Pe exhibited excellent internal reliability in preadolescent children …

Pathologically Activated Neuroprotection Via Uncompetitive Blockade Of N-Methyl-D-Aspartate Receptors With Fast Off-Rate By Novel Multifunctional Dimer Bis(Propyl)-Cognitin, Jialie Luo, Wenming Li, Yuming Zhao, Hongjun Fu, Dik-Lung Ma, Jing Tang, Chaoying Li, Robert W. Peoples, Fushun Li, Qinwen Wang, Pingbo Huang, Jun Xia, Yuanping Pang, Yifan Han

Biomedical Sciences Faculty Research and Publications

Uncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists with fast off-rate (UFO) may represent promising drug candidates for various neurodegenerative disorders. In this study, we report that bis(propyl)-cognitin, a novel dimeric acetylcholinesterase inhibitor and γ-aminobutyric acid subtype A receptor antagonist, is such an antagonist of NMDA receptors. In cultured rat hippocampal neurons, we demonstrated that bis(propyl)-cognitin voltage-dependently, selectively, and moderately inhibited NMDA-activated currents. The inhibitory effects of bis(propyl)-cognitin increased with the rise in NMDA and glycine concentrations. Kinetics analysis showed that the inhibition was of fast onset and offset with an off-rate time constant of 1.9 s. Molecular docking simulations showed moderate …

High-Throughput Experimental Studies To Identify Mirna Targets Directly, With Special Focus On The Mammalian Brain, Peter T. Nelson, Marianthi Kiriakidou, Zissimos Mourelatos, Grace S. Tan, Mary H. Jennings, Kevin Xie, Wang-Xia Wang

Pathology and Laboratory Medicine Faculty Publications

We review the pertinent literature on methods used in high-throughput experimental identification of microRNA (miRNA) "targets" with emphasis on neurochemical studies. miRNAs are short regulatory noncoding RNAs that play important roles in the mammalian brain. The functions of miRNAs are related to their binding of RNAs including mRNAs. Since mammalian miRNAs tend to bind to target mRNAs via imperfect complementarity, understanding exactly which target mRNAs are recognized by which specific miRNAs is a challenge. Based on early experimental evidence, a set of "binding rules" for miRNAs has been described. These have focused on the 5' "seed" region of miRNAs binding …

Q-Ve-Oph, A Negative Control For O-Phenoxy-Conjugated Caspase Inhibitors, Benjamin Southerland, Kashmira Kulkarni-Datar, Chanel Keoni, Rebecca Bricker, William C. Grunwald Jr., Daniel M. Ketcha, Eugene Hern, David R. Cool, Thomas L. Brown

Neuroscience, Cell Biology & Physiology Faculty Publications

The broad-spectrum apoptosis (caspase) inhibitor, Q-VD-OPh, has been shown to have no side effects and is effective at a much lower concentration than other FMK-type caspase inhibitors. However, an appropriate negative control to use with this inhibi- tor has not been available. In this study, we developed and analyzed a new compound, based on the Q-VD-OPh backbone, which acts as a cognate negative control. To create the negative control, we substituted a glutamate residue for the aspartate residue to create Q-VE-OPh, thereby retaining the identical charge and molecular properties with only the addition of an extra –CH2 group. The purity …

Individual Micrornas (Mirnas) Display Distinct Mrna Targeting "Rules", Wang-Xia Wang, Bernard R. Wilfred, Kevin Xie, Mary H. Jennings, Yanling Hu, Arnold J. Stromberg, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

MicroRNAs (miRNAs) guide Argonaute (AGO)-containing microribonucleoprotein (miRNP) complexes to target mRNAs.It has been assumed that miRNAs behave similarly to each other with regard to mRNA target recognition. The usual assumptions, which are based on prior studies, are that miRNAs target preferentially sequences in the 3'UTR of mRNAs,guided by the 5' "seed" portion of the miRNAs. Here we isolated AGO- and miRNA-containing miRNPs from human H4 tumor cells by co-immunoprecipitation (co-IP) with anti-AGO antibody. Cells were transfected with miR-107, miR-124,miR-128, miR-320, or a negative control miRNA. Co-IPed RNAs were subjected to downstream high-density Affymetrix Human Gene 1.0 ST microarray analyses using …

Tetrahydroisoquinoline Neurotoxins In Parkinson Disease, Michael G. Decuypere

Theses and Dissertations (ETD)

The goal of this dissertation work was to (1) determine the distribution of several tetrahydroisoquinoline (TIQ) derivatives in rodent, normal human and Parkinson disease (PD) brain, (2) quantify the levels of these TIQ derivatives in common food sources in an effort to link specific food intake patterns with the development of PD and (3) examine the neurotoxicity of select TIQ derivatives in human dopaminergic cell culture. The TIQs are a family of monoamine alkaloids that share structural homology with 1-methyl-4-phenyl-1,2,3,6-tetrahyrdropyridine (MPTP), can be formed from dopamine or its oxidized metabolites and may be involved in the pathogenesis of monoaminergic cell …

H5n1 Influenza Virus Induces A Parkinsonian Pathology, Haeman Jang

Theses and Dissertations (ETD)

The greatest threat for an influenza pandemic at this time is posed by the highly pathogenic H5N1 avian influenza virus. To date, 63% of the 436 known human cases of H5N1 infection have proven fatal. Animals infected by H5N1 viruses have demonstrated acute neurological signs ranging from mild encephalitis to motor disturbances and coma. However, no studies have examined the longer-term neurologic consequences of H5N1 infection. We show that this virus travels from the peripheral nervous system into the central nervous system (CNS) to higher levels of the neuroaxis, using C57BL/6J mice that are infected by the A/VN/1203/04 H5N1 virus …

Assessing Sleep Quality In Young Adult College Students, Aged 18 - 24 In Relation To Quality Of Life And Anthropometrics, Douglas Mathews

Electronic Theses and Dissertations

Little is known about the impact of sleep on quality of life and anthropometrics in young adults. College students (n=218) were recruited through a variety of methods for a study on weight management for obesity prevention and randomized into control (n=108) or treatment (n=110) groups. Of those, 152 (71%) completed pre- and post-tests, including the Pittsburg Sleep Quality Index (PSQI), scored 0-4 =normal and 5-21=disordered, (a=0.80), the General Health Questionnaire-12 (GHQ), scored from 0-14=good quality of life to 15-36=poor quality of life, (ct=0.87), and anthropometrics. Statistical analyses included linear regression, one way ANOVA, chi-square analysis, and Pearson's Product-Moment Correlation. Significance …

Neurocognitive Impairment Among Hiv-Positive Individuals In Botswana: A Pilot Study, Kathy Lawler, Mosepele Mosepele, Sarah Ratcliffe, Esther Seloilwe, Katherine Steele, Rudo Nthobatsang, Andrew P. Steenhoff

Botswana-UPenn Scholarly Publications

Background

The primary objective of this study was to determine the prevalence of neurocognitive impairment among HIV-positive individuals in Botswana, using the International HIV Dementia Scale (IHDS). We also compared performance on the IHDS with performance on tests of verbal learning/memory and processing speed, and investigated the association between performance on the IHDS and such variables as depression, age, level of education and CD4 count.

Methods

We conducted a cross-sectional study of 120 HIV-positive individuals randomly selected from an outpatient HIV clinic in Gaborone, Botswana. Patients provided a detailed clinical history and underwent neuropsychological testing; measures of depression, daily activities …

Neuronbank: A Tool For Cataloging Neuronal Circuitry, Paul S. Katz, Robert Calin-Jageman, Akshaye Dhawan, Chad Frederick, Shuman Guo, Rasanjalee Dissanayaka, Naveen Hiremath, Wenjun Ma, Xiuyn Shen, Hsui C. Wang, Hong Yang, Sushil Prasad, Rajshekhar Sunderraman, Ying Zhu

Computer Science Faculty Publications

The basic unit of any nervous system is the neuron. Therefore, understanding the operation of nervous systems ultimately requires an inventory of their constituent neurons and synaptic connectivity, which form neural circuits. The presence of uniquely identifi able neurons or classes of neurons in many invertebrates has facilitated the construction of cellular-level connectivity diagrams that can be generalized across individuals within a species. Homologous neurons can also be recognized across species. Here we describe NeuronBank.org, a web-based tool that we are developing for cataloging, searching, and analyzing neuronal circuitry within and across species. Information from a single species is represented …

Development Of A Functional Mri Olfactory Protocol, Jeremy Mangum

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many people can spend a few days with an acute form of sinusitis, a stuffy nose, or sinus congestion that inhibits their ability to smell, but there are fourteen million Americans over the age of fifty that suffer from some form of chronic olfactory dysfunction. Some neurological disorders such as Parkinson's disease and Alzheimer's disease have demonstrated that olfactory dysfunction is a frequent and early sign. While these diseases have no known cure, there are medicines that exist to slow the progression of such debilitating illnesses. By identifying such diseases in their early stages, we can improve the quality of …

Motor Output Evoked By Subsaccadic Stimulation Of Primate Frontal Eye Fields., Brian D Corneil, James K Elsley, Benjamin Nagy, Sharon L Cushing

Brain and Mind Institute Researchers' Publications

In addition to its role in shifting the line of sight, the oculomotor system is also involved in the covert orienting of visuospatial attention. Causal evidence supporting this premotor theory of attention, or oculomotor readiness hypothesis, comes from the effect of subsaccadic threshold stimulation of the oculomotor system on behavior and neural activity in the absence of evoked saccades, which parallels the effects of covert attention. Here, by recording neck-muscle activity from monkeys and systematically titrating the level of stimulation current delivered to the frontal eye fields (FEF), we show that such subsaccadic stimulation is not divorced from immediate motor …