Neurology Commons^™

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 …

Acute Effects Of A Selective Cannabinoid-2 Receptor Agonist On Neuroinflammation In A Model Of Traumatic Brain Injury., Melanie B Elliott, Ronald F Tuma, Peter S Amenta, Mary F Barbe, Jack I Jallo

Department of Neurosurgery Faculty Papers

Proposed therapeutic strategies for attenuating secondary traumatic brain injury (TBI) include modulation of acute neuroimmune responses. The goal of this study was to examine the acute effects of cannabinoid-2 receptor (CB(2)R) modulation on behavioral deficits, cerebral edema, perivascular substance P, and macrophage/microglial activation in a murine model of TBI. Thirty male C57BL/6 mice underwent sham surgery, or cortical contusion impact injury (CCI). CCI mice received vehicle or the CB(2)R agonist 0-1966 at 1 and 24 h after injury. Performance on the rotarod, forelimb cylinder, and open-field tests were evaluated before and at 48 h after sham or CCI surgery. Cerebral …

Optimality In Neural Adaptation, Adrienne Fairhall

Systems Science Friday Noon Seminar Series

Nervous systems tune themselves to the statistical structure of the stimuli they encounter. This sensitivity to statistics appears in phenomena ranging over many timescales, from the adaptation of vision to a rapid change in light level to the loss of ability to distinguish the sounds of non-native languages. While multiple neural mechanisms contribute to this on-line learning of stimulus distributions, we show that the intrinsic nonlinearities of single neurons provide them with the ability to represent time-varying stimuli optimally. While such sensitivity to stimulus statistics does not require learning, slower timescales of adaptation are consistent with optimal inference of statistical …

Learning From Mistakes: Improving Initial Fingertip Force Scaling By Observing Lifting Errors, Gavin Buckingham, Minnie Tang, Paul Gribble, Melvyn A. Goodale

Psychology Presentations

• When lifting objects that are lighter or heaver than we expect them to be, individuals typically misapply forces in a way that reflects their prior expectations of heaviness.

• Because we lift in this predictive way, large and small cubes elicit these characteristic errors even when they are adjusted to have equal mass. Lifters will apply too much force to a large cube and substantially less force to a small cube – errors that are rapidly corrected with repeated lifts (Flanagan & Beltzner, 2000).

• When watching others lift objects, an observer’s motor system automatically reacts in a way …

Associatioin Of Plasma Aβ Peptides With Blood Pressure In The Elderly, Jean-Charles Lambert, Jean Dallongeville, Kathryn A. Ellis, Susanna Schraen-Maschke, James Lui, Simon Laws, Julie Dumont, Florence Richard, Dominque Cottel, Claudine Berr, David Ames, Colin L. Masters, Christopher C. Rowe, Cassandra Szoeke, Christophe Tzourio, Jean-Francois Dartigues, Luc Buee, Ralph Martins, Philippe Amouyel

Research outputs 2011

Background Aß peptides are often considered as catabolic by-products of the amyloid ß protein precursor (APP), with unknown physiological functions. However, several biological properties have been tentatively attributed to these peptides, including a role in vasomotion. We assess whether plasma Aß peptide levels might be associated with systolic and diastolic blood pressure values (SBP and DBP, respectively). Methodology/Principal Findings Plasma Aß1-40 and Aß1-42 levels were measured using an xMAP-based assay in 1,972 individuals (none of whom were taking antihypertensive drugs) from 3 independent studies: the French population-based 3C and MONA-LISA (Lille) studies (n = 627 and n = 769, respectively) …

The Effect Of Spiritualism On The Neuropsychological Function Of Memory, Carla Farcello

McNair Poster Presentations

The amount of physiological-neurological research performed over the past few years has dramatically increased due to our ability to view the structure and function of the brain in living human beings. The use of imaging tools has resulted in huge strides forward in unlocking some of the mysteries of the 3 pound universe-the human brain. One of the more unique neural processes being recently addressed is the affect of belief and spiritualism-the sense of being connected to something larger than oneself-on the human brain. This study hypothesized that better memory will be documented among the experimental group who report being …

Acetate Causes Alcohol Hangover Headache In Rats., Christina R Maxwell, Rebecca Jay Spangenberg, Jan B Hoek, Stephen D Silberstein, Michael L Oshinsky

Department of Neurology Faculty Papers

BACKGROUND: The mechanism of veisalgia cephalgia or hangover headache is unknown. Despite a lack of mechanistic studies, there are a number of theories positing congeners, dehydration, or the ethanol metabolite acetaldehyde as causes of hangover headache.

METHODS: We used a chronic headache model to examine how pure ethanol produces increased sensitivity for nociceptive behaviors in normally hydrated rats.

RESULTS: Ethanol initially decreased sensitivity to mechanical stimuli on the face (analgesia), followed 4 to 6 hours later by inflammatory pain. Inhibiting alcohol dehydrogenase extended the analgesia whereas inhibiting aldehyde dehydrogenase decreased analgesia. Neither treatment had nociceptive effects. Direct administration of acetate …

Ms4a4b, A Cd20 Homologue In T Cells, Inhibits T Cell Propagation By Modulation Of Cell Cycle., Hui Xu, Yaping Yan, Mark S Williams, Gregory B Carey, Jingxian Yang, Hongmei Li, Guang-Xian Zhang, Abdolmohamad Rostami

Department of Neurology Faculty Papers

MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural …

Neural Coding And Decoding, Alexander Dimitrov

Systems Science Friday Noon Seminar Series

Methods based on Rate Distortion theory have been successfully used to cluster stimuli and neural responses in order to study neural codes at a level of detail supported by the amount of available data. They approximate the joint stimulus-response distribution by quantizing paired stimulus-response observations into smaller reproductions of the stimulus and response spaces. An optimal quantization is found by maximizing an information-theoretic cost function subject to both equality and inequality constraints, in hundreds to thousands of dimensions. This analytical approach has several advantages over other current approaches:

• it yields the most informative approximation of the encoding scheme given the …

Pontine Haemorrhage Due To Chondrosarcoma Of The Skull Base, Maliha Iqbal Jumani, Roomasa Channa, Sayed Nabeel Zafar, Ather Enam

Section of Neurosurgery

A young adult presented with acute weakness of right side of body and slurring of speech. An initial brain CT scan showed a pontine haemorrhage, however MRI done a few days later revealed a mass in the left parapharyngeal space. Histopathology of the mass revealed that it was a chondrosarcoma. Subsequently the patient was initially treated with chemotherapy and radiotherapy and later surgery. Skull base chondrosarcomabe is to be included in the differentials of a young patient presenting with signs consistent with pontine haemorrhage.

Effect Of Acute Administration Of Angiopoietin-1 In Experimental Traumatic Spinal Cord Injury: Magnetic Resonance Imaging And Neurobehavioral Studies, Chirag B. Patel

Dissertations and Theses (Open Access)

Spinal cord injury (SCI) is a devastating condition that affects people in the prime of their lives. A myriad of vascular events occur after SCI, each of which contributes to the evolving pathology. The primary trauma causes mechanical damage to blood vessels, resulting in hemorrhage. The blood-spinal cord barrier (BSCB), a neurovascular unit that limits passage of most agents from systemic circulation to the central nervous system, breaks down, resulting in inflammation, scar formation, and other sequelae. Protracted BSCB disruption may exacerbate cellular injury and hinder neurobehavioral recovery in SCI.

In these studies, angiopoietin-1 (Ang1), an agent known to reduce …

White Matter Diffusion Alterations In Normal Women At Risk Of Alzheimer's Disease, Charles D. Smith, Himachandra Chebrolu, Anders H. Andersen, David A. Powell, Mark A. Lovell, Shuling Xiong, Brian T. Gold

Neurology Faculty Publications

Increased white matter mean diffusivity and decreased fractional anisotropy (FA) has been observed in subjects diagnosed with mild cognitive impairment (MCI) and Alzheimer's disease (AD). We sought to determine whether similar alterations of white matter occur in normal individuals at risk of AD. Diffusion tensor images were acquired in 42 cognitively normal right-handed women with both a family history of dementia and at least one apolipoprotein E4 allele. These were compared with images from 23 normal women without either AD risk factor. Group analyses were performed using tract-based spatial statistics. Reduced FA was observed in the fronto-occipital and inferior temporal …

Multiport Minimally Invasive Skull Base Surgery: How Many Ports Are Too Many?, Yaron A. Moshel, Theodore H. Schwartz

Department of Neurosurgery Faculty Papers

Surgical access to the ventral skull base has evolved considerably over the past several years with the introduction of minimally invasive endoscopic and endoscope-assisted approaches. The accompanying manuscript by Ciporen et al. demonstrates an addition to this growing body of literature in their description of the feasibility of multiportal endoscopic approaches to the skull base, particularly the precaruncular transorbital approach, in a series of cadaver dissections. Similar to laparoscopic abdominal surgery, which utilizes multiple small ports to improve visualization and manipulation, they envision a modular combination of approaches that allows an endoscope to be placed in one port and surgery …

Molecular Cross Talk Between Misfolded Proteins In Animal Models Of Alzheimer's And Prion Diseases, Rodrigo Morales, Lisbell D Estrada, Rodrigo Diaz-Espinoza, Diego Morales-Scheihing, Maria C Jara, Joaquin Castilla, Claudio Soto

Faculty, Staff and Student Publications

The central event in protein misfolding disorders (PMDs) is the accumulation of a misfolded form of a naturally expressed protein. Despite the diversity of clinical symptoms associated with different PMDs, many similarities in their mechanism suggest that distinct pathologies may cross talk at the molecular level. The main goal of this study was to analyze the interaction of the protein misfolding processes implicated in Alzheimer's and prion diseases. For this purpose, we inoculated prions in an Alzheimer's transgenic mouse model that develop typical amyloid plaques and followed the progression of pathological changes over time. Our findings show a dramatic acceleration …

Progressive Changes In Microglia And Macrophages In Spinal Cord And Peripheral Nerve In The Transgenic Rat Model Of Amyotrophic Lateral Sclerosis, David J. Graber, William F. Hickey, Brent T. Harris

Dartmouth Scholarship

The role of neuroinflammation in motor neuron death of amyotrophic lateral sclerosis (ALS) is unclear. The human mutant superoxide dismutase-1 (hmSOD1)-expressing murine transgenic model of ALS has provided some insight into changes in microglia activity during disease progression. The purpose of this study was to gain further knowledge by characterizing the immunological changes during disease progression in the spinal cord and peripheral nerve using the more recently developed hmSOD1 rat transgenic model of ALS. Using immunohistochemistry, the extent and intensity of tissue CD11b expression in spinal cord, lumbar nerve roots, and sciatic nerve were evaluated in hmSOD1 rats that were …

Laterality, Perception, And Action During The Size-Weight Illusion, Gavin Buckingham, Nathalie S. Ranger, Melvyn A. Goodale

Psychology Presentations

In the classic size-weight illusion (SWI), a small object will feel heavier than an larger object of equal weight (Charpentier, 1891). Individuals continue to perceive this illusory difference in weight long after their gripping and lifting forces have scaled to the actual, identical, mass of the illusion-inducing stimuli (Flanagan & Beltzner, 2000).

The independence of our weight perception and fingertip force application has only been quantified in the right hand of right-handers. The immunity to this perceptual illusion may be affected by manual asymmetries (e.g., Gonzalez, Ganel & Goodale, 2006).

We examined perception of heaviness and fingertip force scaling in …

Interaction Of The Mu-Opioid Receptor With Gpr177 (Wntless) Inhibits Wnt Secretion: Potential Implications For Opioid Dependence., Jay Jin, Saranya Kittanakom, Victoria Wong, Beverly A S Reyes, Elisabeth J Van Bockstaele, Igor Stagljar, Wade Berrettini, Robert Levenson

Department of Neurosurgery Faculty Papers

BACKGROUND: Opioid agonist drugs produce analgesia. However, long-term exposure to opioid agonists may lead to opioid dependence. The analgesic and addictive properties of opioid agonist drugs are mediated primarily via the mu-opioid receptor (MOR). Opioid agonists appear to alter neuronal morphology in key brain regions implicated in the development of opioid dependence. However, the precise role of the MOR in the development of these neuronal alterations remains elusive. We hypothesize that identifying and characterizing novel MOR interacting proteins (MORIPs) may help to elucidate the underlying mechanisms involved in the development of opioid dependence. RESULTS: GPR177, the mammalian ortholog of Drosophila …

Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima

Department of Biochemistry and Molecular Biology Faculty Papers

The amyloid-beta 42 (Abeta42) is thought to play a central role in the pathogenesis of Alzheimer's disease (AD). However, the molecular mechanisms by which Abeta42 induces neuronal dysfunction and degeneration remain elusive. Mitochondrial dysfunctions are implicated in AD brains. Whether mitochondrial dysfunctions are merely a consequence of AD pathology, or are early seminal events in AD pathogenesis remains to be determined. Here, we show that Abeta42 induces mitochondrial mislocalization, which contributes to Abeta42-induced neuronal dysfunction in a transgenic Drosophila model. In the Abeta42 fly brain, mitochondria were reduced in axons and dendrites, and accumulated in the somata without severe mitochondrial …

Traumatic Thoracic Asia A Examinations And Potential For Clinical Trials, James S. Harrop, Md, Mitchell G. Maltenfort, Phd, Fred H. Geisler, Md, Phd, William Coleman, Phd, Linda A.T. Jones, Pt, Ms, Edward Wirth, Md, Alexander Vaccaro, Md, Phd

Department of Neurosurgery Faculty Papers

Study Design: Retrospective review of prospective database

Objectives: To define the variability of neurologic examination and recovery after non-penetrating complete thoracic spinal cord injuries (ASIA A).

Background Data: Neurologic examinations after SCI can be difficult and inconsistent. Unlike cervical SCI patients, alterations in thoracic (below T1) complete SCI (ASIA A – based on the ASIA Impairment Scale [AIS]) patients’ exams are based only on sensory testing, thus changes in the neurological level (NL) are determined only by sensory changes.

Methods: A retrospective review of the placebo control patients in a multicenter prospective database utilized for the pharmacologic trial of Sygen. …

The Production Of Antibody By Invading B Cells Is Required For The Clearance Of Rabies Virus From The Central Nervous System., D Craig Hooper, Timothy W Phares, Marzena J Fabis, Anirban Roy

Department of Cancer Biology Faculty Papers

BACKGROUND: The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.

METHODOLOGY/PRINCIPAL FINDINGS: Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies …

Safe Emergency Management Of Acute Ischemic Stroke: An Academic Community Hospital Decade Experience, John Castaldo, Richard S. Mackenzie Md, Peter J. Barbour Md, Lorraine Spikol, Yevgeniy Isayev, Yuebing Li Phd, Gary Clauser Md, John Margraf Md, Glenn Mackin Md, Faan, Facp, David Richardson, Gavin C. Barr, Jr. Md, Donna Jenny, Susan Nevada, Claranne Mathiesen

Department of Emergency Medicine

No abstract provided.

Disclosure Of Apoe Genotype For Risk Of Alzheimer's Disease, Peter J. Whitehouse, Melissa Barber Butson

Faculty Scholarship

BACKGROUND: The apolipoprotein E (APOE) genotype provides information on the risk of Alzheimer's disease, but the genotyping of patients and their family members has been discouraged. We examined the effect of genotype disclosure in a prospective, randomized, controlled trial. METHODS: We randomly assigned 162 asymptomatic adults who had a parent with Alzheimer's disease to receive the results of their own APOE genotyping (disclosure group) or not to receive such results (nondisclosure group). We measured symptoms of anxiety, depression, and test-related distress 6 weeks, 6 months, and 1 year after disclosure or nondisclosure. RESULTS: There were no significant differences between the …

Prion Protein Glycosylation Is Not Required For Strain-Specific Neurotropism, Justin R. Piro, Brent T. Harris, Koren Nishina, Claudio Soto, Rodrigo Morales, Judy R. Rees, Surachai Supattapone

Dartmouth Scholarship

In this study, we tested the hypothesis that the glycosylation of the pathogenic isoform of the prion protein (PrP^Sc) might encode the selective neurotropism of prion strains. We prepared unglycosylated cellular prion protein (PrP^C) substrate molecules from normal mouse brain by treatment with PNGase F and used reconstituted serial protein cyclic misfolding amplification reactions to produce RML and 301C mouse prions containing unglycosylated PrP^Sc molecules. Both RML- and 301C-derived prions containing unglycosylated PrP^Sc molecules were infectious to wild-type mice, and neuropathological analysis showed that mice inoculated with these samples maintained strain-specific patterns of PrP …

Intravenous Inoculation Of A Bat-Associated Rabies Virus Causes Lethal Encephalopathy In Mice Through Invasion Of The Brain Via Neurosecretory Hypothalamic Fibers., Mirjam A R Preuss, Marie-Luise Faber, Gene S Tan, Michael Bette, Bernhard Dietzschold, Eberhard Weihe, Matthias J Schnell

Department of Microbiology and Immunology Faculty Papers

The majority of rabies virus (RV) infections are caused by bites or scratches from rabid carnivores or bats. Usually, RV utilizes the retrograde transport within the neuronal network to spread from the infection site to the central nervous system (CNS) where it replicates in neuronal somata and infects other neurons via trans-synaptic spread. We speculate that in addition to the neuronal transport of the virus, hematogenous spread from the site of infection directly to the brain after accidental spill over into the vascular system might represent an alternative way for RV to invade the CNS. So far, it is unknown …

A Dissociation Between Perception And Action In The Material‐Weight Illusion, Gavin Buckingham, Jonathan S. Cant, Kai-Ling C. Kao, Melvyn A. Goodale

Psychology Presentations

We examined what forces are applied to objects that elicit this illusion when they are lifted.We predicted that:

(1) Forces on early trials will scale to each participant’s expectations of how much a particular block will weigh ‐ excessive force will be applied to the metal block and insufficient force applied to the polystyrene block.

(2) Forces on later trials will scale to the real weight of each block ‐ identical levels of force applied to all the blocks.

(3) MWI will persist throughout ‐ polystyrene block will feel the heaviest, metal block will feel the lightest.

Grasping And Lifting Different Materials, Gavin Buckingham, Jonathan S. Cant, Melvyn A. Goodale

Psychology Presentations

The material from which an object is made can determine how heavy it feels (Seashore, 1899). Interestingly, a metal block that has been adjusted to have the same size and mass as a polystyrene block will feel lighter than the polystyrene block. We recently showed that participants experiencing this material-weight illusion’ (MWI) do not apply forces that match their perceptual experience of heaviness ‐ just like in the size‐weight illusion ( Flanagan & Beltzner, 2000).

Our previous study showed that forces on early trials were scaled to each participant’s expectations of how much a particular block should weigh ‐ excessive …

The Efficacy Of Surgical Decompression Before 24 Hours Versus 24 To 72 Hours In Patients With Spinal Cord Injury From T1 To L1--With Specific Consideration On Ethics: A Randomized Controlled Trial., Vafa Rahimi-Movaghar, Soheil Saadat, Alexander R Vaccaro, Seyed Mohammad Ghodsi, Mohammad Samadian, Arya Sheykhmozaffari, Seyed Mohammad Safdari, Bahram Keshmirian

Department of Neurosurgery Faculty Papers

BACKGROUND: There is no clear evidence that early decompression following spinal cord injury (SCI) improves neurologic outcome. Such information must be obtained from randomized controlled trials (RCTs). To date no large scale RCT has been performed evaluating the timing of surgical decompression in the setting of thoracolumbar spinal cord injury. A concern for many is the ethical dilemma that a delay in surgery may adversely effect neurologic recovery although this has never been conclusively proven. The purpose of this study is to compare the efficacy of early (before 24 hours) verse late (24-72 hours) surgical decompression in terms of neurological …

Combined Effects Of Hyperglycemic Conditions And Hiv-1 Nef: A Potential Model For Induced Hiv Neuropathogenesis., Edward A Acheampong, Cassandra Roschel, Muhammad Mukhtar, Alagarsamy Srinivasan, Mohammad Rafi, Roger J Pomerantz, Zahida Parveen

Department of Neurology Faculty Papers

Hyperglycemic conditions associated with diabetes mellitus (DM) or with the use of antiretroviral therapy may increase the risk of central nervous system (CNS) disorders in HIV-1 infected patients. In support of this hypothesis, we investigated the combined effects of hyperglycemic conditions and HIV-1 accessory protein Nef on the CNS using both in vitro and in vivo models. Astrocytes, the most abundant glial cell type required for normal synaptic transmission and other functions were selected for our in vitro study. The results show that in vitro hyperglycemic conditions enhance the expression of proinflammatory cytokines including caspase-3, complement factor 3 (C3), and …

Treatment Options For Neuropathic Pain, Sara Akre

Honors Program Theses

Neuropathic pain is caused by injury to or disease of the nervous system. It affects many people around the world and is a symptom of several diseases. In the United States, it is estimated that up to 3% of Americans have neuropathic pain, which costs the healthcare system $40 billion annually (Gilron et al. 2006). It is, unfortunately, difficult to ameliorate or eliminate due to the complexity of the nervous system and its plasticity and is, therefore, a chronic condition. Health care professionals continually struggle to treat patients' pain and, since tolerance to painkillers is easily built up, this often …

Variable Judgments Of Decisional Capacity In Cognitively Impaired Research Subjects, Marion B. Patterson, Peter J. Whitehouse

Faculty Scholarship

OBJECTIVES: To compare assessments of the decisional capacity of cognitively impaired patients by research assistants (RAs) and by family caregiver/proxies and to determine whether either or both groups judge capacity differently depending on the specific (hypothetical) research enrollment decision being made. DESIGN: Cross-sectional. SETTING: Three clinics, one each in Ohio, Kentucky, and Illinois. PARTICIPANTS: One hundred forty-nine patients with established dementia diagnoses and their caregiver/proxies. MEASUREMENTS: As part of a longer interview, patients were asked about future enrollment in five hypothetical research projects with varying risks and benefits. After patients reported each decision and reasons for that decision, RAs (using …