Neurology Commons^™

Cerebellar Dysfunction In A Mouse Model Of Childhood-Onset Manganese-Induced Dystonia Parkinsonism, Alexander N Rodichkin, Amanda M Brown, Pavani Devabathini, Jennifer L Mcglothan, Si Chen, Ajith Pattammattel, Yong S Chu, Tao Lin, Daniel D Pontow, Karam Abilmouna, Ritishka Kapoor, Sarah E Hardin, Yulia Pushkar, Roy V Sillitoe, Tomás R Guilarte

Duncan NRI Faculty and Staff Publications

Humans with pathogenic variants of the manganese (Mn) transporter gene SLC39A14 exhibit highly elevated brain Mn concentrations and childhood-onset dystonia-parkinsonism. Here we show that Slc39a14-knockout (KO) mice, a preclinical model of the disease with elevated Mn concentrations in the CB, express deficits in physiological tremor implicating cerebellar (CB) dysfunction. Imaging of intracellular Mn in Purkinje cells (PCs) using synchrotron-based X-ray fluorescence microscopy confirmed highly elevated Mn concentrations in the PCs of Slc39a14-KO mice. To determine biological pathways altered in the CB of Slc39a14-KO mice relative to wildtype (WT), we performed RNA sequencing and discovered significant upregulation of pathways and genes …

Determining The Effects Of An Hiv Infective Model On The Development Of Neuropathic Pain In Alzheimer’S Disease Model Mice., Ayesha Usman, Megan W. Szobody, Jose Rios, Mohammed Alnoud, Khalid Benamar

Research Colloquium

The purpose of this study is to determine the effect of the Human Immunodeficiency virus (HIV) in producing neuropathic pain in an Alzheimer’s Disease (AD) mouse model. HIV-1 envelope glycoprotein gp120 is correlated with increased release of thermal hyperalgesia and mechanical allodynia mediators from astrocytes and glial cells in rodents, producing the identifiable symptoms of neuropathic pain. Similarly, studies show that 45.8% of AD patients experience chronic pain. The production of an HIV/AD comorbid mouse model will be useful in determining important pathological pathways for neuropathic pain and is vital to future studies in therapeutic approaches to these conditions. Two …

Triple Or Double? Safety Holds Steady In Acute Stenting, Marlon C. Monayao, Kevin Garcia Valdez, Samantha Miller, Ameer E. Hassan

Research Colloquium

Background: Acute stenting is typically performed for patients presenting with focal neurological deficits due to intracranial or extracranial atherosclerotic stenosis. Following the procedure, dual antiplatelet therapy (DAPT) regimen is commonly prescribed to reduce the risk of in-stent thrombosis. However, very few studies have examined safety outcomes in patients already on direct oral anticoagulants (DOACs) who undergo acute carotid or intracranial stenting with subsequent dual anti-platelet regimen (DAPT). The combination of DOAC and DAPT, referred here as triple therapy, is controversial given the increased risk of hemorrhagic transformation. This retrospective cohort study aims to analyze the safety of triple therapy …

No Safety Trade-Off: Triple Therapy Matches Dapt In Acute Stenting With Thrombectomy, Marlon C. Monayao, Kevin Garcia Valdez, Samantha Miller, Ameer E. Hassan

Research Colloquium

Background: Patients who acutely undergo intra- or extracranial stenting are typically placed on a dual antiplatelet therapy (DAPT) regimen to decrease the risk of in-stent thrombosis. However, initiating these medicines in patients who are already on direct oral anticoagulants (DOACs) is controversial due to the increased risk of hemorrhagic transformation. Studies have been done on patients with atrial fibrillation on DOACs who undergo coronary stenting and subsequently begun on DAPT, but there are no corollaries for patients undergoing acute carotid or intra-cranial stenting and associated safety outcomes. This retrospective cohort study aims to bridge that understanding and checked whether …

Wernicke’S Encephalopathy With Classic Triad And Normal Mri In A Young Woman Following Rapid-Sequence Bariatric And Biliary Surgery, Hugo Zamarron, Nina Mourao, Roberto A. Cruz Saldana

Research Colloquium

Background: Wernicke’s encephalopathy is a life-threatening neurological disorder caused by thiamine deficiency, most commonly associated with alcoholism. However, postoperative nutritional deficiencies in young patients undergoing bariatric procedures are increasingly recognized. This case is unique due to the rapid succession of bariatric and cholecystectomy surgeries, development of classic Wernicke’s symptoms with a normal MRI, and diagnostic delay due to overlapping differential diagnoses including intracranial hypotension and myelopathy.

Case Presentation: A 22-year-old woman with class III obesity underwent sleeve gastrectomy in July 2022, followed by significant weight loss and persistent intractable vomiting. Due to suspected gallbladder disease, she underwent a cholecystectomy in …

Corticobasal Syndrome With Mixed Pathology In The Absence Of Grn Mutation: A Clinico-Pathological Case Of Ftld-Tdp With Coexisting Alzheimer’S And Lewy Body Pathology, Hugo Zamarron, David Irwin, Jeffery Phillips, Edward Lee, Matthew Tisdall, Corey Mcmillan

Research Colloquium

Background: Corticobasal syndrome (CBS) is a neurodegenerative disorder characterized by often asymmetric fronto-pariteal and extra-pyramidal features that is traditionally associated with tauopathy, but pathological findings are heterogenous, including other forms of frontotemporal lobar degeneration (FTLD) and mixed pathologies of aging. We present clinical, radiographic, and histopathologic features of asymmetry in a unique patient with CBS and underlying FTLD with TDP-43 pathology (FTLD-TDP), co-occurring with other age-related pathologies.

Case Presentation: A 76-year-old man presented with progressive cognitive and motor dysfunction including asymmetric parkinsonism, left-sided dystonia and rigidity, apraxia, visuospatial impairment, and a subtle social disorder including apathy and social withdrawal. The …

Bilateral Small Vessel Strokes In A Young Male With Coccidioidal Meningitis And Suspected Cns Vasculitis, Hugo Zamarron, Ahsan Ali

Research Colloquium

Background: Cerebral small vessel strokes in young, otherwise healthy adults without traditional vascular risk factors are rare and warrant further investigation. Central nervous system (CNS) vasculitis is an uncommon etiology that may be triggered by infections, including fungal pathogens. This case is notable for a suspected primary CNS vasculitis manifesting as bilateral deep infarcts in the setting of Coccidioidal meningitis. It highlights the importance of considering fungal infections and vasculitis in the differential diagnosis of stroke in younger patients.

Case Presentation: A 32-year-old previously healthy male presented with fever, headache, and was diagnosed with aseptic meningitis. He was later readmitted …

Blue-Shifted Ancyromonad Channelrhodopsins For Multiplex Optogenetics, Elena G Govorunova, Oleg A Sineshchekov, Hai Li, Yueyang Gou, Hongmei Chen, Shuyuan Yang, Yumei Wang, Stephen Mitchell, Alyssa Palmateer, Leonid S Brown, François St-Pierre, Mingshan Xue, John L Spudich

Duncan NRI Faculty and Staff Publications

Light-gated ion channels from protists (channelrhodopsins or ChRs) are optogenetic tools widely used for controlling neurons and cardiomyocytes. Multiplex optogenetic applications require spectrally separated molecules, which are difficult to engineer without disrupting channel function. Scanning numerous sequence databases, we identified three naturally blue-shifted ChRs from ancyromonads. They form a separate branch on the phylogenetic tree and contain residue motifs characteristic of anion ChRs (ACRs). However, only two conduct chloride, whereas the closely related Nutomonas longa homolog generates inward cation currents in mammalian cells under physiological conditions, significantly exceeding those by previously known tools with similar spectral maxima (peak absorption at …

A Puzzling Case Of Visual Disturbances Leads To A Fatal Neurodegenerative Diagnosis, Courtney J. Austin, Aaron Carrillo, Jennifer Rojas Huen, Victoria Parada

Research Colloquium

Background: Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative disease in which early diagnosis is complicated by the presence of early non-specific and atypical presentations. Sporadic CJD (sCJD), the most common type of CJD, is caused by the spread of a disease-forming prion known as PrPSc. PrPSc multiplies and binds to the normal form of prion, or PrP, converting it to an abnormal, structurally altered disease form that spreads throughout the brain. sCJD can initially present with six different phenotypes: cognitive, affective, classic, visual (Heidenhain variant), atactic (Oppenheimer-Brownell variant), and indeterminate. The classic presentation of CJD includes rapidly progressive dementia with …

Case Report: Clonidine Withdrawal-Induced Posterior Reversible Encephalopathy Syndrome (Pres), Aura M. C. Calderon, Francisco Arias, Ivan Mogollon, Luis Salcedo, Hector Arredondo

Research Colloquium

Introduction: Clonidine, an agonist of central α2-adrenergic and imidazoline receptors, possesses the capacity to elicit transient episodes of hypertension succeeded by hypotension and bradycardia. This particular case underscores a rare yet significant complication, Posterior Reversible Encephalopathy Syndrome (PRES), that can occur subsequent to the abrupt cessation of clonidine administration.

Case Presentation: An 18-year-old male with severe asthma and prior ICU admissions presented to the emergency department after two seizures. He had recently been treated for an asthma exacerbation complicated by hypertension, for which clonidine was initiated. He was discharged on clonidine and prednisone but discontinued clonidine the day before admission …

Structural Basis For Mtorc1 Activation On The Lysosomal Membrane, Zhicheng Cui, Alessandra Esposito, Gennaro Napolitano, Andrea Ballabio, James H Hurley

Duncan NRI Faculty and Staff Publications

The mechanistic target of rapamycin complex 1 (mTORC1) integrates growth factor (GF) and nutrient signals to stimulate anabolic processes connected to cell growth and inhibit catabolic processes such as autophagy1,2. GF signalling through the tuberous sclerosis complex regulates the lysosomally localized small GTPase RAS homologue enriched in brain (RHEB)3. Direct binding of RHEB-GTP to the mTOR kinase subunit of mTORC1 allosterically activates the kinase by inducing a large-scale conformational change4. Here we reconstituted mTORC1 activation on membranes by RHEB, RAGs and Ragulator. Cryo-electron microscopy showed that RAPTOR and mTOR interact directly with the membrane. Full engagement of the membrane anchors …

A Single Center Study Of The Symbol Digit Modalities Test As A Screening Tool For Cognitive Impairment In Parkinson’S Disease, Daniyell Thomason, Morganne Manuel, Shannin Moody, Jesus Lovera, Brain Copeland, Deidre Devier

School of Medicine Faculty Publications

Background: Parkinson’s Disease (PD) can include physical signs and possibly cognitive impairment, resulting from the convergence of pathologicalprocesses involving dopaminergic dysfunction, accumulation ofalpha-synuclein, cholinergic deficits, and disruption of otherneurotransmitter systems. We used screening tests to evaluate thecharacteristics of cognitive performance in patients with PD and to assess their validity compared tothe Montreal Cognitive Assessment (MoCA). Methods: This is a natural history study of participants with PD and controls screened for possible cognitive impairment using the MoCA, Symbol Digit Modalities Test (SDMT), and King-Devick (KD). The groups were compared on performance and then factors associated with cognitive performance (age, diagnosis, and …

Performance Of 123i-Ioflupane Spect Striatal Binding In Dementia With Lewy Bodies, Emily F. Maly, Frank P. Difilippo, Brittany Lapin, Yadi Li, Sarah Berman, Andrea C. Bozoki, Jori E. Fleisher, James E. Galvin, David J. Irwin, Carol F. Lippa, Irene Litvan, Debby W. Tsuang, Cyrus P. Zabetian, Angela S. Taylor, Lynn M. Bekris, Oscar L. Lopez, Douglas Galasko, James B. Leverenz

Department of Neurology Faculty Papers

INTRODUCTION: We aimed to determine whether ¹²³I-ioflupane single-photon emission computed tomography (SPECT) striatal binding ratio (SBR) correlated with parkinsonian motor symptoms in dementia with Lewy bodies (DLB) and if SBR predicts worsening of parkinsonism over time.

METHODS: A retrospective cohort study of the U.S. Dementia with Lewy Bodies Consortium dataset including individuals with DLB with baseline ¹²³I-ioflupane SPECT analyzed with DaTQUANT and baseline and 24-month Movement Disorder Society Unified Parkinson's Disease Rating Scale–Part III (MDS-UPDRS-III). A subset had cerebrospinal fluid α-synuclein seed amplification assay (SAA) evaluation.

RESULTS: Baseline mean SBRs were significant predictors of baseline and 24-month MDS-UPDRS-III …

Reaching International Consensus On The Definition Of Refractory Migraine Using The Delphi Method, Jennifer Robblee, Fawad A. Khan, Michael J. Marmura, Hope L. O'Brien, Lawrence D. Robbins, Marielle K. Samaha, Morris Levin, Simona Sacco, Raffaele Ornello, Stephanie J. Nahas, Heike Hesse, Annika Ehrlich, Adam S. Sprouse-Blum, Christina Sun-Edelstein, Bronwyn Jenkins, Elizabeth K, Seng, Shivang Joshi, Meredith J. Barad, Mi Ji Lee, Sheena K. Aurora, Mario Fernando Prieto Peres

Department of Neurology Faculty Papers

Aim: Despite its frequency in tertiary headache centers, the International Classification of Headache Disorders, 3rd edition (ICHD-3) does not include refractory migraine. Multiple definitions have been proposed with a recent 2020 proposal for both refractory migraine and resistant migraine by the European Headache Federation (EHF). The aim is to reach an international consensus on the definition of refractory migraine.

Methods: This study is a Delphi consensus carried out by a group of international experts in headache medicine. Following a focus group, a panel of 20 experts and one facilitator reviewed the EHF proposed criteria to build upon their definitions. The …

Developmental Transformations Of Purkinje Cells Tracked By Dna Electrokinetic Mobility, Cheryl Brandenburg, Garrett W Crutcher, Andrea J Romanowski, Sarah G Donofrio, Lita R Duraine, Richard N A Owusu-Mensah, Benjamin H Cooper, Izumi Sugihara, Gene J Blatt, Roy V Sillitoe, Alexandros Poulopoulos

Duncan NRI Faculty and Staff Publications

Brain development begins with neurogenesis in progenitor zones and ends with expansive, intricately-patterned cellular diversity in the adult brain. We took advantage of bioelectric interactions between DNA and embryonic tissue to perform "stereo-tracking," a developmental targeting strategy that differentially labels cells at different depths within progenitor zones. This 3D labeling was achieved by delivery of plasmids with distinct electrokinetic mobilities in utero. We applied stereo-tracking with light sheet imaging in the cerebellum and identified that Purkinje cells follow embryonically committed developmental trajectories, linking distinct progenitor zone subfields to the mature topography of the cerebellar cortex. We additionally identified an unexpected …

Potential For Therapeutic Alteration Of The Underlying Biology Of Epilepsy, Michael R. Sperling, Jurriaan M. Peters, Qian Wu, Michelle Guignet, H. Steve White, Evelyn K. Shih, Leock Y. Ngo, Enrique Carrazana, Adrian L. Rabinowicz

Department of Neurology Faculty Papers

Approximately 30-35% of people with epilepsy experience seizures despite taking antiseizure medications. Recurrent seizures that are independent of status epilepticus can be associated with neuronal injury and structural changes to the brain, as well as diminished cognitive function, mood, and quality of life. A treatment that alters the underlying biology of epilepsy, thereby reducing the seizure burden and its attendant consequences, would be of great value in preventing these detrimental effects. In this review, we summarize preclinical and clinical research on pharmacological treatments that may favorably alter the underlying biology of epilepsy (i.e., disease modification or antiepileptogenesis). A reduction in …

Computationally Resolved Neuroprogenitor Cell Biomarkers Associate With Human Disorders, Gerarda Cappuccio, William T Choi, Fatih Semerci, Jill A Rosenfeld, Toni Claire Tacorda, Guantong Qi, Anthony W Zoghbi, Yi Zhong, Hu Chen, Pengfei Liu, Zhandong Liu, Mirjana Maletić-Savatić

Duncan NRI Faculty and Staff Publications

Adult hippocampal neurogenesis, the process of generating new neurons, relies on a rare population of neural stem and progenitor cells (NPCs) within the dentate gyrus complex microenvironment. Discovering the specific genes that define these cells is vital yet challenging due to overlapping expression patterns, limiting detection of rare cell populations using traditional approaches. By employing the computational digital sorting algorithm (DSA) that deconvolves complex gene expression data based on pattern recognition, we identified 129 genes enriched in murine NPCs. We validated these genes against published single-cell RNA sequencing (scRNA-seq) data and discovered that 25 human orthologs were known to cause …

High Energy Consumption Characterizes Abnormal Brain State Transitions In Temporal Lobe Epilepsy, Sam S. Javidi, Qirui Zhang, Ankeeta Ankeeta, Michael R. Sperling, Joseph I. Tracy

Farber Institute for Neuroscience Faculty Papers

Temporal lobe epilepsy (TLE) patients experience shifts between non-seizing and seizing brain states, but the structural networks underlying these transitions remain undefined and poorly characterized. We detected dynamic brain states in resting-state fMRI and constructed linked structural networks utilizing multi-shell diffusion-weighted MR data. Leveraging network control theory, we interrogated the structural data for all possible brain state transitions, identifying those requiring abnormal levels of transition energy (low or high) in TLE compared to matched healthy participants (n's = 25). Results revealed three transitions requiring significantly higher energy in TLE; no abnormally low-energy transitions were observed. In HPs, transitions relied on …

Regulation Of Food Intake By Connexin43 Via Adipocyte-Sensory Neuron Electrical Synapses, Xi Chen, Xing Fang, Hong Zhou, Jieyi Meng, Yang He, Leon G Straub, Andrew Lemoff, Clair Crewe, Shangang Zhao, Yong Xu, Yi Zhu

Duncan NRI Faculty and Staff Publications

Background and objective: Connexin43 (Cx43), encoded by Gja1, forms gap junctions between adjacent cells. In adipose tissue, it is upregulated during adipose beiging while downregulated by high-fat-diet (HFD) feeding. Adipocyte-specific Gja1 overexpression enhances adipose tissue beiging in response to mild cold stress of room temperature. Moreover, those mice display a surprising decrease in food intake, but the mechanism remains unclear. This study investigates how adipocyte Cx43 influences feeding behavior.

Methods: Mice with adipose tissue-specific Gja1 overexpression (Adipoq-Cx43) were fed with HFD. Food intake, weight gain, substrate utilization, and serum lipolysis were assessed. RNA-seq, proteomics, and cytokine measurements were employed to …

Implementing A Training Resource For Large-Scale Genomic Data Analysis In The All Of Us Researcher Workbench, Jasmine Baker, Erik Stricker, Julie Coleman, Shamika Ketkar, Taotao Tan, Ashley M Butler, Laterrica Williams, Latanya Hammonds-Odie, Debra Murray, Brendan Lee, Kim C Worley, Elizabeth G Atkinson

Duncan NRI Faculty and Staff Publications

A lack of representation in genomic research and limited access to computational training create barriers for many researchers seeking to analyze large-scale genetic datasets. The All of Us Research Program provides an unprecedented opportunity to address these gaps by offering genomic data from a broad range of participants, but its impact depends on equipping researchers with the necessary skills to use it effectively. The All of Us Biomedical Researcher (BR) Scholars Program at Baylor College of Medicine aims to break down these barriers by providing early-career researchers with hands-on training in computational genomics through the All of Us Evenings with …