Physiological Processes Commons^™

Sexually Dimorphic Effects Of Gpnmb Modulation On Vertebral Bone Mass Regulation And Intravertebral Disc Health, Hakem Altawil, Fayez Safadi

Williams Honors College, Honors Research Projects

Osteoporosis and vertebral degeneration are major contributors to musculoskeletal morbidity, yet the molecular mechanisms regulating vertebral bone and intervertebral disc (IVD) homeostasis remain incompletely understood. GPNMB (osteoactivin) has been identified as a regulator of bone remodeling, though its role in spine health is unclear. This study evaluated the effects of GPNMB deficiency on lumbar vertebral bone microarchitecture and IVD integrity in a sex-dependent context.

Six-month-old male and female wild-type (WT) and GPNMB knockout (KO) mice were analyzed using micro–computed tomography (µCT) of lumbar vertebrae (L4–L6) and histological assessment of the L5–L6 IVD. KO males exhibited increased bone volume fraction, bone …

The Impact Of Gastric Sleeve And Roux-En-Y Gastric Bypass On Chief Cell Function And Protein Digestion In Obese Patients, Garikoitz Mikel Gainza

Honors Undergraduate Theses

Obesity has become one of the largest global health concerns of the 21^st century, correlating with numerous associated diseases. To help address the growing prevalence and burden of obesity, sleeve gastrectomy and Roux-en-Y gastric bypass have become two commonly performed surgical procedures done to promote weight loss by altering the anatomical structure of the stomach and surrounding organs of the gastrointestinal system. Although the benefits of improved metabolism linked to these surgical procedures are well studied, their impact on the physiology of gastric cells, and more specifically chief cells as they relate to protein digestion post-surgery, is yet to …

Resilience And Reality: Exploring The Lived Experiences Of People Living With Hiv In Texas During The Covid-19 Pandemic – A Qualitative Study., Ahmed F. Alanazi

Social Work Dissertations - Archive

This study investigated the lived experiences of individuals living with HIV (PLWH) in the Dallas-Fort Worth (DFW) area of Texas during the COVID-19 pandemic, using an Interpretative Phenomenological Analysis (IPA) framework. The research examined the intersection of health, social dynamics, and psychological resilience among PLWH, who faced compounded vulnerabilities due to systemic inequities and the dual public health crises of HIV and COVID-19. Through semi-structured interviews with ten participants from diverse backgrounds, the study captured the profound impacts of disrupted healthcare systems, heightened stigma, and social isolation on this marginalized population. The findings reveal that the pandemic exacerbated existing inequities …

Six-Month Report Assessing The Feasibility And Effectiveness Of Amniotic Membrane Injections In Patients With Short, Anterior, Urethral Strictures, Nicholas Pryde, Jack Vernocke, Aron Liaw, Michael Sessine, Nivedita Dhar

Medical Student Research Symposium

Introduction: Urethral stricture treatment has high recurrence rates and adjunct injectable agents have been explored. Amniotic membranes (AM) promote apoptosis of pro-inflammatory cells, prevent differentiation of pro-fibrotic cells, and decrease scar formation. These tissues generated interest in reconstructive urethral surgery. Thus, we performed urethral dilation combined with micronized AM injection in urethral scar tissue for treatment of urethral stricture.

Materials and Methods: Adult males with strictures ≤12Fr in diameter and ≤2 cm in length, International Prostate Symptom Score (IPSS) ≥11 and maximum flowrate <15 ml/s. Reconstituted 100mg micronized AM was injected at the time of urethral dilation. Primary study end point was anatomical success (≥14Fr by cystoscopy) at 6 months. Secondary end points were questionnaires, flow rate, and post void residual. Outcomes assessed at baseline, 5 days, 14 days, 3 months, and 6 months post-injection. Safety was analyzed.

Results: Ten men, mean age of 52 ± 15 years, were included. There were 7 patients with …

Maackia Amurensis Seed Lectin (Masl) Increases Movement Velocity Of Mice With Tnfα Induced Rheumatoid Arthritis, Amanda A. Greenspan, Kelly L. Hamilton, Alan J. Shienbaum, Bradford Fischer, Andrea Bottaro, Gary S. Goldberg

Rowan-Virtua Research Day

Up to 70 million people around the world suffer from rheumatoid arthritis. Current treatment options have varied efficacy and can cause unwanted side effects. New approaches are needed to treat this condition. Sialic acid modifications on chondrocyte receptors have been associated with arthritic inflammation and joint destruction. The transmembrane mucin receptor protein podoplanin (PDPN) has been identified as a functionally relevant receptor that presents extracellular sialic acid motifs. PDPN signaling promotes inflammation and invasion associated with arthritis and, therefore, has emerged as a target that can be used to inhibit arthritic inflammation. Maackia amurensis seed lectin (MASL) can target PDPN …

Massive Loss Of Proprioceptive Ia Synapses In Rat Spinal Motoneurons After Nerve Crush Injuries In The Postnatal Period, Ariadna Arbat-Plana, Sara Bolívar, Xavier Navarro, Esther Udina, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Peripheral nerve injuries (PNIs) induce the retraction from the ventral horn of the synaptic collaterals of Ia afferents injured in the nerve, effectively removing Ia synapses from α-motoneurons. The loss of Ia input impairs functional recovery and could explain, in part, better recovery after PNIs with better Ia synaptic preservation. Synaptic losses correlate with injury severity, speed, and efficiency of muscle reinnervation and requires ventral microglia activation. It is unknown whether this plasticity is age dependent. In neonates, axotomized motoneurons and sensory neurons undergo apoptosis, but after postnatal day 10 most survive. The goal of this study was to analyze …

Fast Blue And Cholera Toxin-B Survival Guide For Alpha-Motoneurons Labeling: Less Is Better In Young B6sjl Mice, But More Is Better In Aged C57bl/J Mice, Hasan Farid, Weston B. Gleford, Lori L. Goss, Teresa L. Garrett, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

Fast Blue (FB) and Cholera Toxin-B (CTB) are two retrograde tracers extensively used to label alpha-motoneurons (α-MNs). The overall goals of the present study were to (1) assess the effectiveness of different FB and CTB protocols in labeling α-MNs, (2) compare the labeling quality of these tracers at standard concentrations reported in the literature (FB 2% and CTB 0.1%) versus lower concentrations to overcome tracer leakage, and (3) determine an optimal protocol for labeling α-MNs in young B6SJL and aged C57Bl/J mice (when axonal transport is disrupted by aging). Hindlimb muscles of young B6SJL and aged C57Bl/J mice were intramuscularly …

Motoneuron Excitability Dysfunction In Als: Pseudo-Mystery Or Authentic Conundrum?, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

In amyotrophic lateral sclerosis (ALS), abnormalities in motoneuronal excitability are seen in early pathogenesis and throughout disease progression. Fully understanding motoneuron excitability dysfunction may lead to more effective treatments. Yet decades of research have not produced consensus on the nature, role or underlying mechanisms of motoneuron excitability dysfunction in ALS. For example, contrary to Ca excitotoxicity theory, predictions of motoneuronal hyper-excitability, normal and hypo-excitability have also been seen at various disease stages and in multiple ALS lines. Accordingly, motoneuron excitability dysfunction in ALS is a disputed topic in the field. Specifically, the form (hyper, hypo or unchanged) and what role …

Artificial Gravity Partially Protects Space-Induced Neurological Deficits In Drosophila Melanogaster, Amber M. Paul, Siddhita D. Mhatre, Janani Iyer, Juli Petereit, Roberta M. Dolling-Boreham

Publications

Spaceflight poses risks to the central nervous system (CNS), and understanding neurological responses is important for future missions. We report CNS changes in Drosophila aboard the International Space Station in response to spaceflight microgravity (SFmg) and artificially simulated Earth gravity (SF1g) via inflight centrifugation as a countermeasure. While inflight behavioral analyses of SFmg exhibit increased activity, postflight analysis displays significant climbing defects, highlighting the sensitivity of behavior to altered gravity. Multiomics analysis shows alterations in metabolic, oxidative stress and synaptic transmission pathways in both SFmg and SF1g; however, neurological changes immediately postflight, including neuronal loss, glial cell count alterations, oxidative …

Non-Invasive Transcutaneous Spinal Dc Stimulation As A Neurorehabilitation Als Therapy In Awake G93a Mice: The First Step To Clinical Translation, Morgan M. Highlander, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

Spinal direct current stimulation (sDCS) modulates motoneuron (MN) excitability beyond the stimulation period, making it a potential neurorehabilitation therapy for amyotrophic lateral sclerosis (ALS), a MN degenerative disease in which MN excitability dysfunction plays a critical and complex role. Recent evidence confirms induced changes in MN excitability via measured MN electrophysiological properties in the SOD1 ALS mouse during and following invasive subcutaneous sDCS (ssDCS). The first aim of our pilot study was to determine the clinical potential of these excitability changes at symptom onset (P90-P105) in ALS via a novel non-invasive transcutaneous sDCS (tsDCS) treatment paradigm on un-anesthetized SOD1-G93A mice. …

Suppression Of Store-Operated Calcium Entry Channels And Cytokine Release By Cannabinoids, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

No abstract provided.

The Role Of Microglia In Neuroinflammation Of The Spinal Cord After Peripheral Nerve Injury, Tana S. Pottorf, Travis M. Rotterman, William M. Mccallum, Zoë A. Haley-Johnson, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Peripheral nerve injuries induce a pronounced immune reaction within the spinal cord, largely governed by microglia activation in both the dorsal and ventral horns. The mechanisms of activation and response of microglia are diverse depending on the location within the spinal cord, type, severity, and proximity of injury, as well as the age and species of the organism. Thanks to recent advancements in neuro-immune research techniques, such as single-cell transcriptomics, novel genetic mouse models, and live imaging, a vast amount of literature has come to light regarding the mechanisms of microglial activation and alluding to the function …

Il-10 And Tgf-Β Increase Connexin-43 Expression And Membrane Potential Of Hl-1 Cardiomyocytes Coupled With Raw 264.7 Macrophages, Cora B. Cox, Mike Castro, Thomas L. Brown, Nancy J. Bigley

Neuroscience, Cell Biology & Physiology Faculty Publications

Cardiac resident macrophages facilitate electrical conduction by interacting with cardiomyocytes via connexin-43 (Cx43) hemichannels. Cx43 is critical for impulse propagation and coordination between muscle contractions. Cardiomyocyte electrophysiology can be altered when coupled with noncardiomyocyte cell types such as M2c tissue-resident macrophages. Using cocultures of murine HL-1 cardiomyocytes and RAW 264.7 macrophages, we examined the hypothesis that cytokine signals, TGF-β1 and IL-10, upregulate Cx43 expression at points of contact between the two cell types. These cytokine signals maintain the macrophages in an M2c anti-inflammatory phenotype, mimicking cardiac resident macrophages. The electrophysiology of cardiomyocytes was examined using di-8-ANEPPS potentiometric dye, which reflects …

Acute Oxygen-Sensing Via Mitochondria-Generated Temperature Transients In Rat Carotid Body Type I Cells, Ryan J. Rakoczy, Clay M. Schiebrel, Christopher N. Wyatt

Neuroscience, Cell Biology & Physiology Faculty Publications

The Carotid Bodies (CB) are peripheral chemoreceptors that detect changes in arterial oxygenation and, via afferent inputs to the brainstem, correct the pattern of breathing to restore blood gas homeostasis. Herein, preliminary evidence is presented supporting a novel oxygen-sensing hypothesis which suggests CB Type I cell “hypoxic signaling” may in part be mediated by mitochondria-generated thermal transients in TASK-channel-containing microdomains. Distances were measured between antibody-labeled mitochondria and TASK-potassium channels in primary rat CB Type I cells. Sub-micron distance measurements (TASK-1: 0.33 ± 0.04 µm, n = 47 vs TASK-3: 0.32 ± 0.03 µm, n = …

The Anti-Inflammatory Agent Bindarit Attenuates The Impairment Of Neural Development Through Suppression Of Microglial Activation In A Neonatal Hydrocephalus Mouse Model, Eri Iwasawa, Farrah N. Brown, Crystal Shula, Fatima Kahn, Sang Hoon Lee, Temugin Berta, David R. Ladle, Kenneth Campbell, Francesco T. Mangano, June Goto

Neuroscience, Cell Biology & Physiology Faculty Publications

Neonatal hydrocephalus presents with various degrees of neuroinflammation and long-term neurologic deficits in surgically treated patients, provoking a need for additional medical treatment. We previously reported elevated neuroinflammation and severe periventricular white matter damage in the progressive hydrocephalus (prh) mutant which contains a point mutation in the Ccdc39 gene, causing loss of cilia-mediated unidirectional CSF flow. In this study, we identified cortical neuropil maturation defects such as impaired excitatory synapse maturation and loss of homeostatic microglia, and swimming locomotor defects in early postnatal prh mutant mice. Strikingly, systemic application of the anti-inflammatory small molecule bindarit significantly supports healthy …

Ethanol And Opioids Do Not Act Synergistically To Depress Excitation In Carotid Body Type I Cells, Ryan J. Rakoczy, Kajal Kamra, Yoon-Jae Yi, Christopher N. Wyatt

Neuroscience, Cell Biology & Physiology Faculty Publications

The combination of opioids and ethanol can synergistically depress breathing and the acute ventilatory response to hypoxia. Multiple studies have shown that the underlying mechanisms for this may involve calcium channel inhibition in central neurons. But we have previously identified opioid receptors in the carotid bodies and shown that their activation inhibits calcium influx into the chemosensitive cells. Given that the carotid bodies contribute to the drive to breathe and underpin the acute hypoxic ventilatory response, we hypothesized that ethanol and opioids may act synergistically in these peripheral sensory organs to further inhibit calcium influx and therefore inhibit ventilation.

Methods …

Genetic Targeting Of Adult Renshaw Cells Using A Calbindin 1 Destabilized Cre Allele For Intersection With Parvalbumin Or Engrailed1, Alicia R. Lane, Indeara C. Cogdell, Thomas M. Jessell, Jay B. Bikoff, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Renshaw cells (RCs) are one of the most studied spinal interneurons; however, their roles in motor control remain enigmatic in part due to the lack of experimental models to interfere with RC function, specifically in adults. To overcome this limitation, we leveraged the distinct temporal regulation of Calbindin (Calb1) expression in RCs to create genetic models for timed RC manipulation. We used a Calb1 allele expressing a destabilized Cre (dgCre) theoretically active only upon trimethoprim (TMP) administration. TMP timing and dose influenced RC targeting efficiency, which was highest within the first three postnatal weeks, but specificity was low with …

Nsaids Naproxen, Ibuprofen, Salicylate, And Aspirin Inhibit Trpm7 Channels By Cytosolic Acidification, Rikki Chokshi, Orville Bennett, Tetyana Zhelay, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

Non-steroidal anti-inflammatory drugs (NSAIDs) are used for relieving pain and inflammation accompanying numerous disease states. The primary therapeutic mechanism of these widely used drugs is the inhibition of cyclooxygenase 1 and 2 (COX1, 2) enzymes that catalyze the conversion of arachidonic acid into prostaglandins. At higher doses, NSAIDs are used for prevention of certain types of cancer and as experimental treatments for Alzheimer’s disease. In the immune system, various NSAIDs have been reported to influence neutrophil function and lymphocyte proliferation, and affect ion channels and cellular calcium homeostasis. Transient receptor potential melastatin 7 (TRPM7) cation channels are highly expressed in …

Placenta-Specific Slc38a2/Snat2 Knockdown Causes Fetal Growth Restriction In Mice, Owen R. Vaughan, Katarzyna Maksym, Elena Silva, Kenneth Barentsen, Russel V. Anthony, Sara L. Hillman, Thomas L. Brown, Rebecca Spencer, Anna L. David, Fredrick J. Rosario, Theresa L. Powell, Thomas Jansson

Neuroscience, Cell Biology & Physiology Faculty Publications

Fetal growth restriction (FGR) is a complication of pregnancy that reduces birth weight, markedly increases infant mortality and morbidity and is associated with later-life cardiometabolic disease. No specific treatment is available for FGR. Placentas of human FGR infants have low abundance of sodium-coupled neutral amino acid transporter 2 (Slc38a2/SNAT2), which supplies the fetus with amino acids required for growth. We determined the mechanistic role of placental Slc38a2/SNAT2 deficiency in the development of restricted fetal growth, hypothesizing that placenta-specific Slc38a2 knockdown causes FGR in mice. Using lentiviral transduction of blastocysts with a small hairpin RNA (shRNA), we achieved 59% knockdown of …

Intensity-Dependent Changes In Quantified Resting Cerebral Perfusion With Multiple Sessions Of Transcranial Dc Stimulation, Matthew Sherwood, Lindsey Mcintire, Aaron T. Madaris, Kamin Kim, Charan Ranganath, R. Andy Mckinley

Neuroscience, Cell Biology & Physiology Faculty Publications

Transcranial direct current stimulation (tDCS) to the left prefrontal cortex has been shown to produce broad behavioral effects including enhanced learning and vigilance. Still, the neural mechanisms underlying such effects are not fully understood. Furthermore, the neural underpinnings of repeated stimulation remain understudied. In this work, we evaluated the effects of the repetition and intensity of tDCS on cerebral perfusion [cerebral blood flow (CBF)]. A cohort of 47 subjects was randomly assigned to one of the three groups. tDCS of 1- or 2-mA was applied to the left prefrontal cortex on three consecutive days, and resting CBF was quantified before …

Investigations In The Cellular And Molecular Biology Of Human Airway Mucociliary Tissue, Vincent Manna

Graduate School of Biomedical Sciences Theses and Dissertations

Our laboratory has integrated the use of a human-derived, in vitro model of airway mucociliary tissue. We isolate human nasal epithelial cells (HNECs) from the nasal mucociliary tissue of donors with a small brush and expand the airway progenitor cells in culture. The HNECs are then seeded onto semi-permeable transwell inserts. The inserts are in contact with the media in the lower chamber but don’t contain media in the upper chamber therefore the cells are exposed to the air while drawing nutrients from the media below, this is called the Air-Liquid Interface (ALI). HNECs cultured at the ALI initiate a …

Current State Of Preeclampsia Mouse Models: Approaches, Relevance, And Standardization, Christopher A. Waker, Melissa R. Kaufman, Thomas L. Brown

Neuroscience, Cell Biology & Physiology Faculty Publications

Preeclampsia (PE) is a multisystemic, pregnancy-specific disorder and a leading cause of maternal and fetal death. PE is also associated with an increased risk for chronic morbidities later in life for mother and offspring. Abnormal placentation or placental function has been well-established as central to the genesis of PE; yet much remains to be determined about the factors involved in the development of this condition. Despite decades of investigation and many clinical trials, the only definitive treatment is parturition. To better understand the condition and identify potential targets preclinically, many approaches to simulate PE in mice have been developed and …

The Role Of Action Potential Waveform In Failure Of Excitation Contraction Coupling, Xueyong Wang, Murad Nawaz, Steve R.A. Burke, Roger Bannister, Brent D. Foy, Andrew A. Voss, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

Excitation contraction coupling (ECC) is the process by which electrical excitation of muscle is converted into force generation. Depolarization of skeletal muscle resting potential contributes to failure of ECC in diseases such as periodic paralysis, ICU acquired weakness and possibly fatigue of muscle during vigorous exercise. When extracellular K+ is raised to depolarize the resting potential, failure of ECC occurs suddenly, over a range of several mV of resting potential. While some studies have hypothesized the sudden failure of ECC is due to all-or-none failure of excitation, other studies suggest failure of excitation is graded. Intracellular recordings of action potentials …

Affiliative Social Interactions Activate Vasopressin-Responsive Neurons In The Mouse Dorsal Raphe, Tirth Patel, Hanna O. Caiola, Olivia Mallari, Benjamin D. Rood

Rowan-Virtua Research Day

Social behavior is inextricably linked to human health, shaping both our susceptibility and resilience to disease and stress. Positive interactions as simple as maternal contact or friendships among children and adults can protect against emotional distress and improve treatment outcomes, whereas negative interactions such as abuse, social isolation, or bullying can increase aggression and precipitate mood disorders. Discovering the structure and function of neural circuits underlying social behavior is critical to understanding the link between social interaction and health. The neuropeptide vasopressin has been implicated in the regulation of multiple social interactions including social memory, aggression, mating, pair-bonding, and parental …

Identification Of The E3 Ligase That Directs The Degradation Of Proteins That Control Cell Fate Decisions In Yeast, Prasanna Tati, Stephen D Willis, Katrina F. Cooper

Rowan-Virtua Research Day

The ubiquitin–proteasome system (UPS) and autophagy pathways are distinct, highly conserved proteolytic systems that play important roles in maintaining cellular homeostasis in response to environmental cues [1]. The goal of this project is to identify the E3 ligase that mediates the degradation of cyclin C following nitrogen starvation in yeast using quantitative Western blot analysis of cyclin C-myc following nitrogen starvation in mutants of known Ubc4/5 interacting E3 ligases. No potential E3 ligases were identified as stable after 4 hours of nitrogen starvation, suggesting redundancy in function.

The Mechanism Underlying Transient Weakness In Myotonia Congenita, Jessica H. Myers, Kirsten Denman, Chris Dupont, Ahmed A. Hawash, Kevin R. Novak, Andrew Koesters, Manfred Grabner, Anamika Dayal, Andrew A. Voss, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

In addition to the hallmark muscle stiffness, patients with recessive myotonia congenita (Becker disease) experience debilitating bouts of transient weakness that remain poorly understood despite years of study. We performed intracellular recordings from muscle of both genetic and pharmacologic mouse models of Becker disease to identify the mechanism underlying transient weakness. Our recordings reveal transient depolarizations (plateau potentials) of the membrane potential to -25 to -35 mV in the genetic and pharmacologic models of Becker disease. Both Na + and Ca 2+ currents contribute to plateau potentials. Na + persistent inward current (NaPIC) through Na V 1.4 channels is the …

A Mouse Model Of Huntington’S Disease Shows Altered Ultrastructure Of Transverse Tubules In Skeletal Muscle Fibers, Shannon H. Romer, Sabrina Metzger, Kristiana Peraza, Matthew C. Wright, D. Scott Jobe, Long-Sheng Song, Mark M. Rich, Brent D. Foy, Robert J. Talmadge, Andrew A. Voss

Neuroscience, Cell Biology & Physiology Faculty Publications

Huntington’s disease (HD) is a fatal and progressive condition with severe debilitating motor defects and muscle weakness. Although classically recognized as a neurodegenerative disorder, there is increasing evidence of cell autonomous toxicity in skeletal muscle. We recently demonstrated that skeletal muscle fibers from the R6/2 model mouse of HD have a decrease in specific membrane capacitance, suggesting a loss of transverse tubule (t-tubule) membrane in R6/2 muscle. A previous report also indicated that Cav1.1 current was reduced in R6/2 skeletal muscle, suggesting defects in excitation–contraction (EC) coupling. Thus, we hypothesized that a loss and/or disruption of the skeletal muscle t-tubule …

Measuring Mitochondrial Respiration In Vivo: From Mouse To Human, Arthur Orchanian, Brennan Schilling, Bruce Berkowitz Phd

Medical Student Research Symposium

Introduction: The mitochondrial energy ecosystem can be non-invasively interrogated in photoreceptors by combing a clinical tool, optical coherence tomography (OCT), with a mitochondrial protonophore (2,4 dinitrophenol, DNP). It remains unclear if only supra-clinical doses of DNP will be useful for mouse studies or if lower but clinically relevant doses of DNP would facilitate translation from mice to humans.

Methods: The experiment was a paired longitudinal design that took place over 2 days. On day 1, C57BL/6J mice were overnight dark adapted, then light-adapted for 5 h before OCT examination before regaining consciousness; a similar procedure was followed on day 2 …

Effects Of Neuronic Shutter Observed In The Eeg Alpha Rhythm, Kevin E. Alexander, Justin R. Estepp, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

The posterior alpha (α) rhythm, seen in human electroencephalogram (EEG), is posited to originate from cycling inhibitory/excitatory states of visual relay cells in the thalamus. These cycling states are thought to lead to oscillating visual sensitivity levels termed the “neuronic shutter effect.” If true, perceptual performance should be predictable by observed α phase (of cycling inhibitory/excitatory states) relative to the timeline of afferentiation onto the visual cortex. Here, we tested this hypothesis by presenting contrast changes at near perceptual threshold intensity through closed eyelids to 20 participants (balanced for gender) during times of spontaneous α oscillations. To more accurately and …

Conditional Loss Of Engrailed 1/2 In Rhombic Lip-Derived Neurons Increases Intrinsic Rhythmicity And Decreases Overall Variability Of Eupneic Respiration, Angela P. Taylor

Theses and Dissertations (ETD)

Evidence for a cerebellar role during cardiopulmonary challenges has long been established, but investigation into cerebellar involvement in eupneic breathing has been inconclusive. Given the view of the cerebellum (CRB) as a temporally coordinating structure, any investigation into the CRB during respiration must evaluate rhythm and variability of the respiratory sequence. In this study, we chose an elegant model of cerebellar neuropathology, Atoh1-En1/2 CKO, where mutant animals have conditional loss of the developmental patterning gene Engrailed 1/2 in rhombic lip-lineage neurons and exhibit a proportional scaling-down of neuron number in hypoplastic lobules of the CRB. We utilized whole-body unrestrained plethysmography …