Neurosciences Commons^™

Cerebral Functional Connectivity Periodically (De)Synchronizes With Anatomical Constraints., Raphaël Liégeois, Erik Ziegler, Christophe Phillips, Pierre Geurts, Francisco Gómez, Mohamed Ali Bahri, B T Thomas Yeo, Andrea Soddu, Audrey Vanhaudenhuyse, Steven Laureys, Rodolphe Sepulchre

Brain and Mind Institute Researchers' Publications

This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber tractography. Instead of a static analysis based on the correlation between SC and FC averaged over the entire fMRI time series, we propose a dynamic analysis, based on the time evolution of the correlation between SC and a suitably windowed FC. Assessing the statistical significance of the time series against random phase permutations, our data show a pronounced peak of significance for time window widths around 20-30 TR (40-60 s). Using the appropriate window …

Collective Timekeeping Among Cells Of The Master Circadian Clock, Jennifer A. Evans

Biomedical Sciences Faculty Research and Publications

The suprachiasmatic nucleus (SCN) of the anterior hypothalamus is the master circadian clock that coordinates daily rhythms in behavior and physiology in mammals. Like other hypothalamic nuclei, the SCN displays an impressive array of distinct cell types characterized by differences in neurotransmitter and neuropeptide expression. Individual SCN neurons and glia are able to display self-sustained circadian rhythms in cellular function that are regulated at the molecular level by a 24h transcriptional–translational feedback loop. Remarkably, SCN cells are able to harmonize with one another to sustain coherent rhythms at the tissue level. Mechanisms of cellular communication in the SCN network are …

The Concerted Regulation Of Intracellular Signaling By Amyloid Precursor Protein And Aβ Peptide, Lisa Kirouac

USF Tampa Graduate Theses and Dissertations

It is widely accepted that A-beta (Aβ) generated from amyloid precursor protein (APP) oligomerizes and fibrillizes to form neuritic plaques in the Alzheimer’s disease (AD) brain, yet little is known about the contribution of APP preceding AD pathogenesis. Our data presented here suggest that APP has a functional role in cell cycle regulation and proliferation. First, we demonstrat that APP is pathologically phosphorylated at Thr₆₆₈ and that P-APP localizes to the centrosomes. Furthermore, P-APP is proteolytically processed in a cell cycle -dependent manner to generate its pathogenic metabolites. Using Stable Isotope Labeling by Amino Acids in Culture (SILAC) and …

Mtor: Alzheimer's Disease Prevention For Apoe4 Carriers, Ai-Ling Lin, D. Allan Butterfield, Arlan Richardson

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

The Influence Of Motivational Salience On Attention Selection: An Erp Investigation, Constanza De Dios

USF Tampa Graduate Theses and Dissertations

The current study used event-related potentials (ERPs) to investigate how motivational salience in the form of expectation violation influences spatial attention. The medial frontal negativity (MFN) ERP indexes expected value, being negative to unexpected punishments and positive to unexpected rewards. The P1 and N1 ERPs index spatial attention, being larger to stimuli in attended locations. This design attached motivational value to locations by making one visual hemifield economically rewarding (greater probability of a rewarding outcome) and the other punishing (greater probability of a punishing outcome). Keypresses to a dot probe following a reward-signifying stimulus were awarded money if correct, and …

Static And Dynamic Spectral Acuity In Cochlear Implant Listeners For Simple And Speech-Like Stimuli, Benjamin Anderson Russell

USF Tampa Graduate Theses and Dissertations

For cochlear implant (CI) listeners, poorer than normal speech recognition abilities are typically attributed to degraded spectral acuity. However, estimates of spectral acuity have most often been obtained using simple (tonal) stimuli, presented directly to the implanted electrodes, rather than through the speech processor as occurs in everyday listening. Further, little is known about spectral acuity for dynamic stimuli, as compared to static stimuli, even though the perception of dynamic spectral cues is important for speech perception.

The primary goal of the current study was to examine spectral acuity in CI listeners, and a comparison group of normal hearing (NH) …

Can Gait Signatures Provide Quantitative Measures For Aiding Clinical Decision-Making? A Systematic Meta-Analysis Of Gait Variability Behavior In Patients With Parkinson’S Disease, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

A disturbed, inconsistent walking pattern is a common feature of patients with Parkinson's disease (PwPD). Such extreme variability in both temporal and spatial parameters of gait has been associated with unstable walking and an elevated prevalence of falls. However, despite their ability to discretise healthy from pathological function, normative variability values for key gait parameters are still missing. Furthermore, an understanding of each parameter's response to pathology, as well as the inter-parameter relationships, has received little attention. The aim of this systematic literature review and meta-analysis was therefore to define threshold levels for pathological gait variability as well as to …

Combining Real-Time Fmri Neurofeedback Training Of The Dlpfc With N-Back Practice Results In Neuroplastic Effects Confined To The Neurofeedback Target Region, Matthew Sherwood, Michael P. Weisend, Jessica H. Kane, Jason G. Parker

Neuroscience, Cell Biology & Physiology Faculty Publications

In traditional fMRI, individuals respond to exogenous stimuli and are naïve to the effects of the stimuli on their neural activity patterns. Changes arising in the fMRI signal are analyzed post-hoc to elucidate the spatial and temporal activation of brain regions associated with the tasks performed. The advent of real-time fMRI has enabled a new method to systematically alter brain activity across space and time using neurofeedback training (NFT), providing a new tool to study internally-driven processes such as neuroplasticity. In this work, we combined n-back practice with fMRI-NFT of the left dorsolateral prefrontal cortex (DLPFC) to better understand the …

N-Acetyl Cysteine May Support Dopamine Neurons In Parkinson's Disease: Preliminary Clinical And Cell Line Data., Daniel A. Monti, George Zabrecky, Daniel Kremens, Tsao-Wei Liang, Nancy A. Wintering, Jingli Cai, Xiatao Wei, Anthony J. Bazzan, Li Zhong, Brendan Bowen, Charles Intenzo, Lorraine Iacovitti, Andrew B. Newberg

Marcus Institute of Integrative Health Faculty Papers

BACKGOUND: The purpose of this study was to assess the biological and clinical effects of n-acetyl-cysteine (NAC) in Parkinson's disease (PD).

METHODS: The overarching goal of this pilot study was to generate additional data about potentially protective properties of NAC in PD, using an in vitro and in vivo approach. In preparation for the clinical study we performed a cell tissue culture study with human embryonic stem cell (hESC)-derived midbrain dopamine (mDA) neurons that were treated with rotenone as a model for PD. The primary outcome in the cell tissue cultures was the number of cells that survived the insult …

Inhibiting The Interaction Between Grp94 And Myocilin To Treat Primary Open-Angle Glaucoma, Andrew Stothert

USF Tampa Graduate Theses and Dissertations

Glaucoma is a neurodegenerative protein misfolding disorder classified by increases in IOP, damage to retinal ganglion cells (RGCs), optic nerve (ON) head damage, and progressive irreversible blindness. Primary open-angle glaucoma (POAG) is the most common form of glaucoma, constituting over 90% of clinical cases. POAG is observed in patients where normal outflow channels, mainly the trabecular meshwork (TM), are exposed at the angle formed by the iris and cornea. However, due to TM cellular dysfunction, aqueous outflow resistance is increased preventing normal circulation of aqueous humor. Recent studies have shown that in 2-4% of POAG cases, increased intracellular levels of …

Traumatic Brain Injury Increases Levels Of Mir-21 In Extracellular Vesicles: Implications For Neuroinflammation, Emily B. Harrison, Colleen G. Hochfelder, Benjamin G. Lamberty, Brittney M. Meays, Brenda M. Morsey, Matthew L. Kelso, Howard S. Fox, Sowmya V. Yelamanchili

Journal Articles: Pharmacology & Experimental Neuroscience

No abstract provided.

Pruning Or Tuning? Maturational Profiles Of Face Specialization During Typical Development, Xun Zhu, Ramesh S. Bhatt, Jane E. Joseph

Psychology Faculty Publications

Introduction: Face processing undergoes significant developmental change with age. Two kinds of developmental changes in face specialization were examined in this study: specialized maturation, or the continued tuning of a region to faces but little change in the tuning to other categories; and competitive interactions, or the continued tuning to faces accompanied by decreased tuning to nonfaces (i.e., pruning). Methods: Using fMRI, in regions where adults showed a face preference, a face- and object-specialization index were computed for younger children (5-8 years), older children (9-12 years) and adults (18-45 years). The specialization index was scaled to each subject's maximum activation …

The Effects Of Cognitive Training Among Individuals With Neurodegenerative Diseases, Elise Gabriela Valdes

USF Tampa Graduate Theses and Dissertations

With the growing older adult population, neurodegenerative diseases common in old age such as mild cognitive impairment (MCI) or Parkinson’s disease (PD) are becoming increasingly germane areas of research. Pharmacological treatments have thus far been unsuccessful in treating cognitive decline associated with these neurodegenerative disorders. Alternative interventions, such as cognitive training programs, have shown promise. The current dissertation contains three papers examining cognitive interventions in neurodegenerative diseases. The first paper examined the longitudinal effects of cognitive speed of processing training (SPT) among those with PD. Results showed that training gains seen at initial post-test were maintained three months later. The …

Communication-Microelectrode Detection Of Cholesterol Efflux From The Human Buccel Mucosa, Xiaochun Yu, Thomas J. Kelley, Hillel J. Chiel, James D. Burgess

Faculty Scholarship

It has previously demonstrated that cholesterol efflux from the cell plasma membrane is increased in a mouse model of cystic fibrosis (CF) compared to a wild-type control. A noninvasive means of characterizing plasma membrane cholesterol efflux at the surface of airway tissue of CF patients is needed to extend the trends found in animal models of CF to the human disease state. Microelectrode-induced cholesterol efflux from the plasma membrane of cells at the surface of tissue is proposed as a strategy to demonstrate increased cholesterol efflux for CF in human subjects. Data demonstrating detection of cholesterol efflux from the human …

1st Place Research Paper: The Effectiveness Of Yoga Therapy On An Adult, Post-Stroke Population: A Systematic Review, Baylor E. Hogan

Kevin and Tam Ross Undergraduate Research Prize

Objectives: The objectives of this paper are to (1) give a brief overview of stroke pathophysiology (2) outline yoga as a therapeutic strategy (3) present the current research on yoga rehabilitation for stroke (4) discuss the efficacy of yoga for chronic stroke.

Methods: Relevant terms were searched in PubMed, Web of Science, Academic OneFile, ScienceDirect, and Google Scholar electronic databases. Studies were excluded if they contained pediatric stroke, non-stroke neurological diseases, or subjects with comorbidities. Statistically significant data was extracted for the primary measures of nine trials.

Results: Four studies measured statistically significant outcomes (p<0.05). These included improvements in balance, independence, endurance, trait anxiety, fear of falling, self-efficacy, pain, strength, range of motion (ROM), activity, participation, and quality of life (QoL). Discussion: Lack of statistical significance in post-stroke depression (PSD) measures may be due to inadequate intervention length or a psychosocial cause of depression. Improvements in balance, flexibility, and strength from yoga participation permitted progress in disability and functionality. Finally, overall health-related quality of life (HRQL) is affected by the severity of mental disorders and physical disability. Yoga can have a positive effect in both domains and therefore, may improve HRQL.

Conclusion: …

Role Of Histidine 547 Of Human Dopamine Transporter In Molecular Interaction With Hiv-1 Tat And Dopamine Uptake, Yaxia Yuan, Pamela M. Quizon, Wei-Lun Sun, Jianzhuang Yao, Jun Zhu, Chang-Guo Zhan

Molecular Modeling and Biopharmaceutical Center Faculty Publications

HIV-1 Tat plays an important role in HIV-associated neurocognitive disorders (HAND) by disrupting neurotransmission including dopamine uptake by human dopamine transporter (hDAT). Previous studies have demonstrated that HIV-1 Tat directly binds to hDAT and some amino-acid mutations that attenuate the hDAT-Tat binding also significantly decreased dopamine uptake activity of hDAT. This combined computational-experimental study demonstrates that histidine-547 (H547) of hDAT plays a crucial role in the hDAT-Tat binding and dopamine uptake by hDAT, and that the H547A mutation can not only considerably attenuate Tat-induced inhibition of dopamine uptake, but also significantly increase the V_max of hDAT for dopamine uptake. …

Targeting Tau Degradation By Small Molecule Inhibitors For Treatment Of Tauopathies, Mackenzie Martin

USF Tampa Graduate Theses and Dissertations

Tauopathies are neurodegenerative diseases that affect millions of people around the world. Tauopathies include more than 20 neurodegenerative diseases. Some of the most common tauopathies are Alzheimer’s disease (AD), frontotemporal dementia (FTD), chronic traumatic encephalopathy (CTE), Pick’s disease, corticobasal degeneration, progressive supranuclear palsy (PSP), agyrophillic grain disease, and amyotrophic lateral sclerosis (ALS). These diseases can cause significant memory loss, behavioral changes, motor deficits and speech impairments. Tauopathies stem from accumulation of the microtubule associated protein tau (MAPT). Tau stabilizes microtubules and helps with axonal transport. In a disease state tau becomes hyperphosphorylated and truncated leading to its aggregation. More recently …

Insights Into Quasar Uv Spectra Using Unsupervised Clustering Analysis, A Tammour, S.C. Gallagher, M Daley, G.T. Richards

Brain and Mind Institute Researchers' Publications

Machine learning techniques can provide powerful tools to detect patterns in multidimensional parameter space. We use K-means - a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabelled data - to study a sample of quasar UV spectra from the Quasar Catalog of the 10th Data Release of the Sloan Digital Sky Survey (SDSS-DR10) of Paris et al. Detecting patterns in large data sets helps us gain insights into the physical conditions and processes giving rise to the observed properties of quasars. We use K-means to find clusters in the parameter space of the equivalent width (EW), …

The Relationship Between Lexical Performance And Regional Gray Matter Volumes: A Longitudinal Study Of Cognitively Healthy Elderly, Jungmoon Hyun

Dissertations, Theses, and Capstone Projects

This study investigated the longitudinal relationship among aging, performance on lexical tasks, and regional gray matter volumes over 2-7 years. A total of 137 older participants who remained cognitively normal were administered four lexical tasks at each time point: the Boston Naming Test (BNT), Vocabulary Test, Semantic- and Phonemic-Fluency task. In addition, they underwent repeated magnetic resonance imaging (MRI) scanning acquired within two months of the lexical tasks. The average interval between time points was 2.36 years (range 1.50-7.64) and the average number of time points was 2.65 times (range 2-5).

Results indicated that age differentially affects lexical task performance …

Intersubunit Interactions At Putative Sites Of Ethanol Action In The M3 And M4 Domains Of The Nmda Receptor Glun1 And Glun2b Subunits, Robert W. Peoples, Hong Ren, Yulin Zhao

Biomedical Sciences Faculty Research and Publications

Background and Purpose: The N-methyl-D-aspartate (NMDA) receptor is an important target of alcohol action in the brain. Recent studies in this laboratory have demonstrated that alcohol-sensitive positions in the intersubunit interfaces of the M3 and M4 domains of GluN1 and GluN2A subunits interact with respect to ethanol sensitivity and receptor kinetics, and that alcohol-sensitive positions in the M domains of GluN2A and GluN2B subunits differ. In this study we tested for interactions among alcohol-sensitive positions at the M domain intersubunit interfaces in GluN1/GluN2B NMDA receptors.

Experimental Approach: We used whole-cell patch-clamp recording in tsA201 cells expressing tryptophan substitution mutants at …

Carotid Ultrasound Is Not Helpful In Simple Syncope, Nicholus Yee M.D., Shilin Patel M.D., Raymond Gong

Clinical Research in Practice: The Journal of Team Hippocrates

A critical appraisal and clinical application of Scott JW, Schwartz AL, Gates JD, Gerhard-Herman M, Havens JM. Choosing wisely for syncope: low-value carotid ultrasound use. J Am Heart Assoc. 2014 Aug 13;3(4). pii: e001063. doi: 10.1161/JAHA.114.001063

Prior Binge Ethanol Exposure Potentiates The Microglial Response In A Model Of Alcohol-Induced Neurodegeneration, Simon Alex Marshall, Chelsea Rhea Geil Nickell, Kimberly Nixon

Pharmaceutical Sciences Faculty Publications

Excessive alcohol consumption results in neurodegeneration which some hypothesize is caused by neuroinflammation. One characteristic of neuroinflammation is microglial activation, but it is now well accepted that microglial activation may be pro- or anti-inflammatory. Recent work indicates that the Majchrowicz model of alcohol-induced neurodegeneration results in anti-inflammatory microglia, while intermittent exposure models with lower doses and blood alcohol levels produce microglia with a pro-inflammatory phenotype. To determine the effect of a repeated binge alcohol exposure, rats received two cycles of the four-day Majchrowicz model. One hemisphere was then used to assess microglia via immunohistochemistry and while the other was used …

Synapse Formation In Monosynaptic Sensory–Motor Connections Is Regulated By Presynaptic Rho Gtpase Cdc42, Fumiyasu Imai, David R. Ladle, Jennifer R. Leslie, Xin Duan, Tilat A. Rizvi, Georgianne M. Ciraolo, Yi Zheng, Yutaka Yoshida

Neuroscience, Cell Biology & Physiology Faculty Publications

Spinal reflex circuit development requires the precise regulation of axon trajectories, synaptic specificity, and synapse formation. Of these three crucial steps, the molecular mechanisms underlying synapse formation between group Ia proprioceptive sensory neurons and motor neurons is the least understood. Here, we show that the Rho GTPase Cdc42 controls synapse formation in monosynaptic sensory–motor connections in presynaptic, but not postsynaptic, neurons. In mice lacking Cdc42 in presynaptic sensory neurons, proprioceptive sensory axons appropriately reach the ventral spinal cord, but significantly fewer synapses are formed with motor neurons compared with wild-type mice. Concordantly, electrophysiological analyses show diminished EPSP amplitudes in monosynaptic …

Optogenetic Interrogation Of Functional Synapse Formation By Corticospinal Tract Axons In The Injured Spinal Cord, Naveen Jayaprakash, Zimei Wang, Brian Hoeynck, Nicholas Krueger, Audra A. Kramer, Eric Balle, Daniel S. Wheeler, Robert A. Wheeler, Murray G. Blackmore

Biomedical Sciences Faculty Research and Publications

To restore function after injury to the CNS, axons must be stimulated to extend into denervated territory and, critically, must form functional synapses with appropriate targets. We showed previously that forced overexpression of the transcription factor Sox11 increases axon growth by corticospinal tract (CST) neurons after spinal injury. However, behavioral outcomes were not improved, raising the question of whether the newly sprouted axons are able to form functional synapses. Here we developed an optogenetic strategy, paired with single-unit extracellular recordings, to assess the ability of Sox11-stimulated CST axons to functionally integrate in the circuitry of the cervical spinal cord. Initial …

Reverse Engineering A Kinetic Model Of A Dopaminergic Neuron To Apoptosis, Johnathan Morris

Biology and Medicine Through Mathematics Conference

No abstract provided.

Revealing The Quality Of Movement: A Meta-Analysis Review To Quantify The Thresholds To Pathological Variability During Standing And Walking, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

Neuromotor processes are inherently noisy, which results in variability during movement and fluctu-ations in motor control. Although controversial, low levels of variability are traditionally considered healthy, while increased levels are thought to be pathological. This systematic review and meta-analysisof the literature investigates the thresholds between healthy and pathological task variability.

After examining 13,195 publications, 109 studies were included. Results from over 3000 healthy sub-jects and 2775 patients revealed an overall positive effect size of pathology on variability of 0.59 forwalking and 0.80 for sway. For the coefficient of variation of stride time (ST) and sway area (SA), upperthresholds of 2.6% …

Focusing On Selection For Fixation, John K. Tsotsos, Calden Wloka, Yulia Kotseruba

MODVIS Workshop

Building on our presentation at MODVIS 2015, we continue in our quest to discover a functional, computational, explanation of the relationship among visual attention, interpretation of visual stimuli, and eye movements, and how these produce visual behavior. Here, we focus on one component, how selection is accomplished for the next fixation. The popularity of saliency map models drives the inference that this is solved; we suggested otherwise at MODVIS 2015. Here, we provide additional empirical and theoretical arguments. We then develop arguments that a cluster of complementary, conspicuity representations drive selection, modulated by task goals and history, leading to a …

Metabolic Drift In The Aging Brain., Julijana Ivanisevic, Kelly L. Stauch, Michael Petrascheck, H. Paul Benton, Adrian A. Epstein, Mingliang Fang, Santhi Gorantla, Minerva Tran, Linh Hoang, Michael E. Kurczy, Michael D. Boska, Howard Gendelman, Howard S. Fox, Gary Siuzdak

Journal Articles: Pharmacology & Experimental Neuroscience

Brain function is highly dependent upon controlled energy metabolism whose loss heralds cognitive impairments. This is particularly notable in the aged individuals and in age-related neurodegenerative diseases. However, how metabolic homeostasis is disrupted in the aging brain is still poorly understood. Here we performed global, metabolomic and proteomic analyses across different anatomical regions of mouse brain at different stages of its adult lifespan. Interestingly, while severe proteomic imbalance was absent, global-untargeted metabolomics revealed an energymetabolic drift or significant imbalance in core metabolite levels in aged mouse brains. Metabolic imbalance was characterized by compromised cellular energy status (NAD decline, increased AMP/ATP, …

Leukemia Inhibitory Factor As A Neuroprotective Agent Against Focal Cerebral Ischemia, Stephanie Davis

USF Tampa Graduate Theses and Dissertations

Previous publications from this laboratory demonstrated that administration of leukemia inhibitory factor (LIF) (125 µg/kg) to young, male Sprague-Dawley rats at 6, 24, and 48 h after middle cerebral artery occlusion (MCAO) reduced infract volume, improved sensimotor skills, and alleviated damage to white matter at 72 h after the injury. In vitro studies using cultured oligodendrocytes (OLs) showed that LIF (200 ng/ml) also protects against 24 h of oxygen-glucose deprivation through activation of Akt signaling and upregulation of the antioxidant enzymes peroxiredoxin IV and metallothionein III. Other groups have demonstrated that LIF reduces neurodegeneration in animal models of disease, but …

The Neural Roots Of Mathematical Expertise, Daniel Ansari

Brain and Mind Institute Researchers' Publications

No abstract provided.