Neurology Commons^™

Intracranial Stimulation And Eeg Feature Analysis Reveal Affective Salience Network Specialization, Brian A Metzger, Prathik Kalva, Madaline M Mocchi, Brian Cui, Joshua A Adkinson, Zhengjia Wang, Raissa Mathura, Kourtney Kanja, Jay Gavvala, Vaishnav Krishnan, Lu Lin, Atul Maheshwari, Ben Shofty, John F Magnotti, Jon T Willie, Sameer A Sheth, Kelly R Bijanki

Faculty, Staff and Students Publications

Emotion is represented in limbic and prefrontal brain areas, herein termed the affective salience network (ASN). Within the ASN, there are substantial unknowns about how valence and emotional intensity are processed-specifically, which nodes are associated with affective bias (a phenomenon in which participants interpret emotions in a manner consistent with their own mood). A recently developed feature detection approach ('specparam') was used to select dominant spectral features from human intracranial electrophysiological data, revealing affective specialization within specific nodes of the ASN. Spectral analysis of dominant features at the channel level suggests that dorsal anterior cingulate (dACC), anterior insula and ventral-medial …

Symptomatic Obstructive Hydrocephalus Caused By Choroid Plexus Hyperplasia In A Pediatric Patient: Illustrative Case, Ana Sofia Alvarez, John P Mcginnis, Rajan Patel, Howard L Weiner

Faculty, Staff and Students Publications

BACKGROUND: Choroid plexus hyperplasia has been described as a rare cause of communicating hydrocephalus due to cerebrospinal fluid (CSF) overproduction. However, this is the first report of symptomatic obstructive hydrocephalus caused by mechanical obstruction of the aqueduct by a hyperplastic choroid plexus.

OBSERVATIONS: A 4-year-old male presented with headaches and intermittent emesis. Magnetic resonance imaging (MRI) of the brain showed abnormal enlargement of the choroid plexus in the lateral ventricles with extension into the third ventricle, resulting in obstruction of the aqueduct of Sylvius, leading to obstructive hydrocephalus. Endoscopic third ventriculostomy (ETV) was chosen as the surgical treatment. During the …

Clinical Genome Sequencing: Three Years’ Experience At A Tertiary Children’S Hospital, Runjun D Kumar, Lisa F Saba, Haley Streff, Chad A Shaw, Elizabeth Mizerik, Matthew T Snyder, Dolores Lopez-Terrada, Jennifer Scull

Duncan NRI Faculty and Staff Publications

Purpose: Genome sequencing (GS) may shorten the diagnostic odyssey for patients, but clinical experience with this assay in nonresearch settings remains limited. Texas Children's Hospital began offering GS as a clinical test to admitted patients in 2020, providing an opportunity to study GS utilization, possibilities for test optimization, and testing outcomes.

Methods: We retrospectively reviewed GS orders for admitted patients for a nearly 3-year period from March 2020 through December 2022. We gathered anonymized clinical data from the electronic health record to answer the study questions.

Results: The diagnostic yield over 97 admitted patients was 35%. The majority of GS …

Dimensionality Reduction For Improving Out-Of-Distribution Detection In Medical Image Segmentation, Mckell Woodland, Nihil Patel, Mais Al Taie, Joshua P Yung, Tucker J Netherton, Ankit B Patel, Kristy K Brock

Faculty, Staff and Students Publications

Clinically-deployed deep learning-based segmentation models are known to fail on data outside of their training distributions. While clinicians review the segmentations, these models do tend to perform well in most instances, which could exacerbate automation bias. Therefore, it is critical to detect out-of-distribution images at inference to warn the clinicians that the model likely failed. This work applies the Mahalanobis distance post hoc to the bottleneck features of a Swin UNETR model that segments the liver on T1-weighted magnetic resonance imaging. By reducing the dimensions of the bottleneck features with principal component analysis, images the model failed on were detected …

Expert Panel Curation Of 113 Primary Mitochondrial Disease Genes For The Leigh Syndrome Spectrum, Elizabeth M Mccormick, Kierstin Keller, Julie P Taylor, Alison J Coffey, Lishuang Shen, Danuta Krotoski, Brian Harding, Xiaowu Gai, Marni J Falk, Zarazuela Zolkipli-Cunningham, Shamima Rahman

Children’s Nutrition Research Center Staff Publications

Objective: Primary mitochondrial diseases (PMDs) are heterogeneous disorders caused by inherited mitochondrial dysfunction. Classically defined neuropathologically as subacute necrotizing encephalomyelopathy, Leigh syndrome spectrum (LSS) is the most frequent manifestation of PMD in children, but may also present in adults. A major challenge for accurate diagnosis of LSS in the genomic medicine era is establishing gene-disease relationships (GDRs) for this syndrome with >100 monogenic causes across both nuclear and mitochondrial genomes.

Methods: The Clinical Genome Resource (ClinGen) Mitochondrial Disease Gene Curation Expert Panel (GCEP), comprising 40 international PMD experts, met monthly for 4 years to review GDRs for LSS. The GCEP …

Pirh2-Dependent Dna Damage In Neurons Induced By The G-Quadruplex Ligand Pyridostatin, Rocio Diaz Escarcega, Abhijeet A Patil, Jose F Moruno-Manchon, Akihiko Urayama, Sean P Marrelli, Nayun Kim, David Monchaud, Louise D Mccullough, Andrey S Tsvetkov

Faculty, Staff and Student Publications

Noncanonical base pairing between four guanines (G) within single-stranded G-rich sequences leads to formation of а G-quartet. Self-stacking of G-quartets results in a columnar four-stranded DNA structure known as the G-quadruplex (G4 or G4-DNA). In cancer cells, G4-DNA regulates multiple DNA-dependent processes, including transcription, replication, and telomere function. How G4s function in neurons is poorly understood. Here, we performed a genome-wide gene expression analysis (RNA-Seq) to identify genes modulated by a G4-DNA ligand, pyridostatin (PDS), in primary cultured neurons. PDS promotes stabilization of G4 structures, thus allowing us to define genes directly or indirectly responsive to G4 regulation. We found …

Sepsis Exacerbates Alzheimer’S Disease Pathophysiology, Modulates The Gut Microbiome, Increases Neuroinflammation And Amyloid Burden, Vijayasree V Giridharan, Celso S G Catumbela, Carlos Henrique R Catalão, Juneyoung Lee, Bhanu P Ganesh, Fabricia Petronilho, Felipe Dal-Pizzol, Rodrigo Morales, Tatiana Barichello

Faculty, Staff and Student Publications

While our understanding of the molecular biology of Alzheimer's disease (AD) has grown, the etiology of the disease, especially the involvement of peripheral infection, remains a challenge. In this study, we hypothesize that peripheral infection represents a risk factor for AD pathology. To test our hypothesis, APP/PS1 mice underwent cecal ligation and puncture (CLP) surgery to develop a polymicrobial infection or non-CLP surgery. Mice were euthanized at 3, 30, and 120 days after surgery to evaluate the inflammatory mediators, glial cell markers, amyloid burden, gut microbiome, gut morphology, and short-chain fatty acids (SCFAs) levels. The novel object recognition (NOR) task …

X, But Not Y, Chromosomal Complement Contributes To Stroke Sensitivity In Aged Animals, Shaohua Qi, Conelius Ngwa, Abdullah Al Mamun, Sharmeen Romana, Ting Wu, Sean P Marrelli, Arthur P Arnold, Louise D Mccullough, Fudong Liu

Faculty, Staff and Student Publications

Post-menopausal women become vulnerable to stroke and have poorer outcomes and higher mortality than age-matched men, and previous studies suggested that sex chromosomes play a vital role in mediating stroke sensitivity in the aged. It is unknown if this is due to effects of the X or Y chromosome. The present study used the XY* mouse model (with four genotypes: XX and XO gonadal females and XY and XXY gonadal males) to compare the effect of the X vs. Y chromosome compliment in stroke. Aged (18-20 months) and gonadectomized young (8-12 weeks) mice were subjected to a 60-min middle cerebral …

Hiccups: Nerve Irritation Or Masquerading As Acute Coronary Syndrome, Dessiree Cordero, Patrik Schmidt, Franklin Sosa, Maulin Patel, Eduard Sklyar

Faculty, Staff and Student Publications

The typical clinical presentation of acute coronary syndrome (ACS) includes chest pain that may radiate to the left arm, shoulder, jaw, and neck, accompanied by diaphoresis, dyspnea, nausea, vomiting, and hiccups, which have been observed as the sole symptom of presentation. The mechanism of hiccups involves the activation of the vagus and phrenic nerves, leading to the activation of the diaphragm and intercostal muscles. Several hypotheses link hiccups to ACS, associating irritation of the left anterior descending artery with activation of sympathetic phrenic and vagal nerves. This case report highlights the occurrence of hiccups in patients with inferior and right …

A Cross-Species Proteomic Map Reveals Neoteny Of Human Synapse Development, Li Wang, Kaifang Pang, Li Zhou, Arantxa Cebrián-Silla, Susana González-Granero, Shaohui Wang, Qiuli Bi, Matthew L White, Brandon Ho, Jiani Li, Tao Li, Yonatan Perez, Eric J Huang, Ethan A Winkler, Mercedes F Paredes, Rothem Kovner, Nenad Sestan, Alex A Pollen, Pengyuan Liu, Jingjing Li, Xianhua Piao, José Manuel García-Verdugo, Arturo Alvarez-Buylla, Zhandong Liu, Arnold R Kriegstein

Faculty, Staff and Students Publications

The molecular mechanisms and evolutionary changes accompanying synapse development are still poorly understood1,2. Here we generate a cross-species proteomic map of synapse development in the human, macaque and mouse neocortex. By tracking the changes of more than 1,000 postsynaptic density (PSD) proteins from midgestation to young adulthood, we find that PSD maturation in humans separates into three major phases that are dominated by distinct pathways. Cross-species comparisons reveal that human PSDs mature about two to three times slower than those of other species and contain higher levels of Rho guanine nucleotide exchange factors (RhoGEFs) in the …

Cardiac Magnetic Resonance Imaging To Determine Single Ventricle Function In A Pediatric Population Is Feasible In A Large Trial Setting: Experience From The Single Ventricle Reconstruction Trial Longitudinal Follow Up, Jon Detterich, Michael D Taylor, Timothy C Slesnick, Michael Dilorenzo, Anthony Hlavacek, Christopher Z Lam, Shagun Sachdeva, Sean M Lang, M Jay Campbell, Jennifer Gerardin, Kevin K Whitehead, Rahul H Rathod, Mark Cartoski, Shaji Menon, Felicia Trachtenberg, Russell Gongwer, Jane Newburger, Caren Goldberg, Adam L Dorfman, The Pediatric Heart Network Investigators

Faculty, Staff and Students Publications

The Single Ventricle Reconstruction (SVR) Trial was a randomized prospective trial designed to determine survival advantage of the modified Blalock-Taussig-Thomas shunt (BTTS) vs the right ventricle to pulmonary artery conduit (RVPAS) for patients with hypoplastic left heart syndrome. The primary aim of the long-term follow-up (SVRIII) was to determine the impact of shunt type on RV function. In this work, we describe the use of CMR in a large cohort follow up from the SVR Trial as a focused study of single ventricle function. The SVRIII protocol included short axis steady-state free precession imaging to assess single ventricle systolic function …

Noninvasive Neuromonitoring With Rheoencephalography: A Case Report, Louis A Cannizzaro, Ifeanyi Iwuchukwu, Victoria Rahaman, Mohammad Hirzallah, Michael Bodo

Faculty, Staff and Students Publications

Cerebral blood flow (CBF) autoregulation (AR) can be monitored using invasive modalities, such as intracranial pressure (ICP) and arterial blood pressure (ABP) to calculate the CBF AR index (PRx). Monitoring PRx can reduce the extent of secondary brain damage in patients. Rheoencephalography (REG) is an FDA-approved non-invasive method to measure CBF. REGx, a CBF AR index, is calculated from REG and arm bioimpedance pulse waves. Our goal was to test REG for neuromonitoring. 28 measurement sessions were performed on 13 neurocritical care patients. REG/arm bioimpedance waveforms were recorded on a laptop using a bioimpedance amplifier and custom-built software. The same …

A Novel Pathogenic Mutation Of Mecp2 Impairs Chromatin Association Independent Of Protein Levels, Jian Zhou, Claudia Cattoglio, Yingyao Shao, Harini P Tirumala, Carlo Vetralla, Sameer S Bajikar, Yan Li, Hu Chen, Qi Wang, Zhenyu Wu, Bing Tang, Mahla Zahabiyon, Aleksandar Bajic, Xiangling Meng, Jack J Ferrie, Anel Lagrone, Ping Zhang, Jean J Kim, Jianrong Tang, Zhandong Liu, Xavier Darzacq, Nathaniel Heintz, Robert Tjian, Huda Y Zoghbi

Faculty, Staff and Students Publications

Loss-of-function mutations in MECP2 cause Rett syndrome (RTT), a severe neurological disorder that mainly affects girls. Mutations in MECP2 do occur in males occasionally and typically cause severe encephalopathy and premature lethality. Recently, we identified a missense mutation (c.353G>A, p.Gly118Glu [G118E]), which has never been seen before in MECP2, in a young boy who suffered from progressive motor dysfunction and developmental delay. To determine whether this variant caused the clinical symptoms and study its functional consequences, we established two disease models, including human neurons from patient-derived iPSCs and a knock-in mouse line. G118E mutation partially reduces MeCP2 abundance …

A Pancreatic Player In Dementia: Pathological Role For Islet Amyloid Polypeptide Accumulation In The Brain, Angelina S Bortoletto, Ronald J Parchem

Faculty, Staff and Students Publications

Type 2 diabetes mellitus patients have a markedly higher risk of developing dementia. While multiple factors contribute to this predisposition, one of these involves the increased secretion of amylin, or islet amyloid polypeptide, that accompanies the pathophysiology of type 2 diabetes mellitus. Islet amyloid polypeptide accumulation has undoubtedly been implicated in various forms of dementia, including Alzheimer’s disease and vascular dementia, but the exact mechanisms underlying islet amyloid polypeptide’s causative role in dementia are unclear. In this review, we have summarized the literature supporting the various mechanisms by which islet amyloid polypeptide accumulation may cause neuronal damage, ultimately leading to …

Convergent Escape Behaviour From Distinct Visual Processing Of Impending Collision In Fish And Grasshoppers, Richard B Dewell, Terri Carroll-Mikhail, Margaret R Eisenbrandt, Alexander F Mendoza, Bidisha Halder, Thomas Preuss, Fabrizio Gabbiani

Faculty, Staff and Students Publications

In animal species ranging from invertebrate to mammals, visually guided escape behaviours have been studied using looming stimuli, the two-dimensional expanding projection on a screen of an object approaching on a collision course at constant speed. The peak firing rate or membrane potential of neurons responding to looming stimuli often tracks a fixed threshold angular size of the approaching stimulus that contributes to the triggering of escape behaviours. To study whether this result holds more generally, we designed stimuli that simulate acceleration or deceleration over the course of object approach on a collision course. Under these conditions, we found that …

Efficacy Of Scrambler Therapy In Patients With Painful Diabetic Peripheral Neuropathy: A Single-Arm, Prospective, Pilot Study, Seung Hee Yoo, Won-Joong Kim, Ji Seon Chae, Bo Kyung Kang, Min Jeong Kang, Min Hyouk Beak

Faculty, Staff and Student Publications

BACKGROUND: A variety of medications are available to manage painful diabetic peripheral neuropathy (DPN), but the proper treatment remains challenging. Accordingly, various neuromodulation modalities have been used. However, no prospective clinical trials have evaluated the use of scrambler therapy (ST) in painful DPN. This study aimed to explore the long-term effects of ST in managing painful DPN.

METHODS: The patients received 10 consecutive STs of 45 minutes every 1 to 2 days. The primary outcome was pain score. We measured the visual analog scale (VAS) pain scores at baseline, during ST, immediately after ST, and at 1, 2, 3, and …

An Ecchordosis Physaliphora, A Rare Entity, Involving The Central Nervous System: A Systematic Review Of The Literature, Rajesh K Gupta, Thejasvi A Reddy, Ashutosh Gupta, Rohan Samant, Carlos A Perez, Anam Haque

Faculty, Staff and Student Publications

Ecchordosis physaliphora (EP) is a benign notochordal remnant, which is often an incidental finding; however, it can rarely present with neurological symptoms. We performed a systematic review of the literature for cases of symptomatic EP published in PubMed, Web of Science and Embase from January 1982 to May 2023. This is the largest review to date and revealed 60 cases including ours. Headache (55%) and CSF rhinorrhea (32%) were the most frequent clinical manifestations. The majority of symptomatic EP lesions were located in the prepontine region (77%) and required surgical resection (75%). EP should be considered in patients with neurologic …

Pet Imaging Of Microglia Using Pbr28suv Determines Therapeutic Efficacy Of Autologous Bone Marrow Mononuclear Cells Therapy In Traumatic Brain Injury, Supinder S Bedi, Michael C Scott, Max A Skibber, Akshita Kumar, Henry W Caplan, Hasen Xue, David Sequeira, Alison L Speer, Fanni Cardenas, Franciska Gudenkauf, Karen Uray, Amit K Srivastava, Alan R Prossin, Charles S Cox

Faculty, Staff and Student Publications

Traumatic brain injury (TBI) results in activated microglia. Activated microglia can be measured in vivo by using positron emission topography (PET) ligand peripheral benzodiazepine receptor standardized uptake values (PBR28suv). Cell based therapies have utilized autologous bone marrow mononuclear cells (BMMNCs) to attenuate activated microglia after TBI. This study aims to utilize in vivo PBR28suv to assess the efficacy of BMMNCs therapy after TBI. Seventy-two hours after CCI injury, BMMNCs were harvested from the tibia and injected via tail-vein at 74 h after injury at a concentration of 2 million cells per kilogram of body weight. There were three groups of …

An Ecchordosis Physaliphora, A Rare Entity, Involving The Central Nervous System: A Systematic Review Of The Literature, Rajesh K Gupta, Thejasvi A Reddy, Ashutosh Gupta, Rohan Samant, Carlos A Perez, Anam Haque

Faculty, Staff and Student Publications

Ecchordosis physaliphora (EP) is a benign notochordal remnant, which is often an incidental finding; however, it can rarely present with neurological symptoms. We performed a systematic review of the literature for cases of symptomatic EP published in PubMed, Web of Science and Embase from January 1982 to May 2023. This is the largest review to date and revealed 60 cases including ours. Headache (55%) and CSF rhinorrhea (32%) were the most frequent clinical manifestations. The majority of symptomatic EP lesions were located in the prepontine region (77%) and required surgical resection (75%). EP should be considered in patients with neurologic …

Novel Genetic And Phenotypic Expansion In Gosr2-Related Progressive Myoclonus Epilepsy, Lea Hentrich, Mered Parnes, Timothy Edward Lotze, Rohini Coorg, Tom J De Koning, Kha M Nguyen, Calvin K Yip, Heinz Jungbluth, Anne Koy, Hormos Salimi Dafsari

Faculty, Staff and Students Publications

Biallelic variants in the Golgi SNAP receptor complex member 2 gene (GOSR2) have been reported in progressive myoclonus epilepsy with neurodegeneration. Typical clinical features include ataxia and areflexia during early childhood, followed by seizures, scoliosis, dysarthria, and myoclonus. Here, we report two novel patients from unrelated families with a GOSR2-related disorder and novel genetic and clinical findings. The first patient, a male compound heterozygous for the GOSR2 splice site variant c.336+1G>A and the novel c.364G>A,p.Glu122Lys missense variant showed global developmental delay and seizures at the age of 2 years, followed by myoclonus at the age …

Dopamine Signaling From Ganglion Cells Directs Layer-Specific Angiogenesis In The Retina, Justine H Liang, Viktor Akhanov, Anthony Ho, Mohamed Tawfik, Shane P D'Souza, Morven A Cameron, Richard A Lang, Melanie A Samuel

Faculty, Staff and Students Publications

During central nervous system (CNS) development, a precisely patterned vasculature emerges to support CNS function. How neurons control angiogenesis is not well understood. Here, we show that the neuromodulator dopamine restricts vascular development in the retina via temporally limited production by an unexpected neuron subset. Our genetic and pharmacological experiments demonstrate that elevating dopamine levels inhibits tip-cell sprouting and vessel growth, whereas reducing dopamine production by all retina neurons increases growth. Dopamine production by canonical dopaminergic amacrine interneurons is dispensable for these events. Instead, we found that temporally restricted dopamine production by retinal ganglion cells (RGCs) modulates vascular development. RGCs …

Transcriptomic Analysis Of Stem Cells From Chorionic Villi Uncovers The Impact Of Chromosomes 2, 6 And 22 In The Clinical Manifestations Of Down Syndrome, Salvatore Vaiasicca, Gianmarco Melone, David W James, Marcos Quintela, Alessandra Preziuso, Richard H Finnell, Robert Steven Conlan, Lewis W Francis, Bruna Corradetti

Faculty, Staff and Students Publications

BACKGROUND: Down syndrome (DS) clinical multisystem condition is generally considered the result of a genetic imbalance generated by the extra copy of chromosome 21. Recent discoveries, however, demonstrate that the molecular mechanisms activated in DS compared to euploid individuals are more complex than previously thought. Here, we utilize mesenchymal stem cells from chorionic villi (CV) to uncover the role of comprehensive functional genomics-based understanding of DS complexity.

METHODS: Next-generation sequencing coupled with bioinformatic analysis was performed on CV obtained from women carrying fetuses with DS (DS-CV) to reveal specific genome-wide transcriptional changes compared to their euploid counterparts. Functional assays were …

Kcnq2/3 Gain-Of-Function Variants And Cell Excitability: Differential Effects In Ca1 Versus L2/3 Pyramidal Neurons, Nissi Varghese, Bruno Moscoso, Ana Chavez, Kristen Springer, Erika Ortiz, Heun Soh, Sabato Santaniello, Atul Maheshwari, Anastasios V Tzingounis

Faculty, Staff and Students Publications

Gain-of-function (GOF) pathogenic variants in the potassium channels KCNQ2 and KCNQ3 lead to hyperexcitability disorders such as epilepsy and autism spectrum disorders. However, the underlying cellular mechanisms of how these variants impair forebrain function are unclear. Here, we show that the R201C variant in KCNQ2 has opposite effects on the excitability of two types of mouse pyramidal neurons of either sex, causing hyperexcitability in layer 2/3 (L2/3) pyramidal neurons and hypoexcitability in CA1 pyramidal neurons. Similarly, the homologous R231C variant in KCNQ3 leads to hyperexcitability in L2/3 pyramidal neurons and hypoexcitability in CA1 pyramidal neurons. However, the effects of KCNQ3 …

Classification Of Missense Variants In The N-Methyl-D-Aspartate Receptor Grin Gene Family As Gain- Or Loss-Of-Function, Scott J Myers, Hongjie Yuan, Riley E Perszyk, Jing Zhang, Sukhan Kim, Kelsey A Nocilla, James P Allen, Jennifer M Bain, Johannes R Lemke, Dennis Lal, Timothy A Benke, Stephen F Traynelis

Faculty, Staff and Student Publications

Advances in sequencing technology have generated a large amount of genetic data from patients with neurological conditions. These data have provided diagnosis of many rare diseases, including a number of pathogenic de novo missense variants in GRIN genes encoding N-methyl-d-aspartate receptors (NMDARs). To understand the ramifications for neurons and brain circuits affected by rare patient variants, functional analysis of the variant receptor is necessary in model systems. For NMDARs, this functional analysis needs to assess multiple properties in order to understand how variants could impact receptor function in neurons. One can then use these data to determine whether the …

Systematic-Narrative Hybrid Literature Review: Crosstalk Between Gastrointestinal Renin–Angiotensin And Dopaminergic Systems In The Regulation Of Intestinal Permeability By Tight Junctions, Ivan Coronado, Samiksha Pachade, Emanuele Trucco, Rania Abdelkhaleq, Juntao Yan, Sergio Salazar-Marioni, Amanda Jagolino-Cole, Mozhdeh Bahrainian, Roomasa Channa, Sunil A Sheth, Luca Giancardo

Faculty, Staff and Student Publications

Vessel segmentation in fundus images permits understanding retinal diseases and computing image-based biomarkers. However, manual vessel segmentation is a time-consuming process. Optical coherence tomography angiography (OCT-A) allows direct, non-invasive estimation of retinal vessels. Unfortunately, compared to fundus images, OCT-A cameras are more expensive, less portable, and have a reduced field of view. We present an automated strategy relying on generative adversarial networks to create vascular maps from fundus images without training using manual vessel segmentation maps. Further post-processing used for standard en face OCT-A allows obtaining a vessel segmentation map. We compare our approach to state-of-the-art vessel segmentation algorithms trained …

Structure, Function, And Molecular Landscapes Of The Aging Retina, Jeffrey D Zhu, Sharma Pooja Tarachand, Qudrat Abdulwahab, Melanie A Samuel

Faculty, Staff and Students Publications

Because the central nervous system is largely nonrenewing, neurons and their synapses must be maintained over the lifetime of an individual to ensure circuit function. Age is a dominant risk factor for neural diseases, and declines in nervous system function are a common feature of aging even in the absence of disease. These alterations extend to the visual system and, in particular, to the retina. The retina is a site of clinically relevant age-related alterations but has also proven to be a uniquely approachable system for discovering principles that govern neural aging because it is well mapped, contains diverse neuron …

Hematopoietic Stem And Progenitor Cells Confer Cross-Protective Trained Immunity In Mouse Models, Bailee N Kain, Brandon T Tran, Pamela N Luna, Ruoqiong Cao, Duy T Le, Marcus A Florez, Laure Maneix, Jack D Toups, Daniel E Morales-Mantilla, Scott Koh, Hyojeong Han, Roman Jaksik, Yun Huang, Andre Catic, Chad A Shaw, Katherine Y King

Duncan NRI Faculty and Staff Publications

Recent studies suggest that infection reprograms hematopoietic stem and progenitor cells (HSPCs) to enhance innate immune responses upon secondary infectious challenge, a process called “trained immunity.” However, the specificity and cell types responsible for this response remain poorly defined. We established a model of trained immunity in mice in response to Mycobacterium avium infection. scRNA-seq analysis revealed that HSPCs activate interferon gamma-response genes heterogeneously upon primary challenge, while rare cell populations expand. Macrophages derived from trained HSPCs demonstrated enhanced bacterial killing and metabolism, and a single dose of recombinant interferon gamma exposure was sufficient to induce similar training. Mice transplanted …

Decoding Depression Severity From Intracranial Neural Activity, Jiayang Xiao, Nicole R Provenza, Joseph Asfouri, John Myers, Raissa K Mathura, Brian Metzger, Joshua A Adkinson, Anusha B Allawala, Victoria Pirtle, Denise Oswalt, Ben Shofty, Meghan E Robinson, Sanjay J Mathew, Wayne K Goodman, Nader Pouratian, Paul R Schrater, Ankit B Patel, Andreas S Tolias, Kelly R Bijanki, Xaq Pitkow, Sameer A Sheth

Faculty, Staff and Students Publications

BACKGROUND: Disorders of mood and cognition are prevalent, disabling, and notoriously difficult to treat. Fueling this challenge in treatment is a significant gap in our understanding of their neurophysiological basis.

METHODS: We recorded high-density neural activity from intracranial electrodes implanted in depression-relevant prefrontal cortical regions in 3 human subjects with severe depression. Neural recordings were labeled with depression severity scores across a wide dynamic range using an adaptive assessment that allowed sampling with a temporal frequency greater than that possible with typical rating scales. We modeled these data using regularized regression techniques with region selection to decode depression severity from …

The Endosomal Escape Vehicle Platform Enhances Delivery Of Oligonucleotides In Preclinical Models Of Neuromuscular Disorders, Xiang Li, Mahboubeh Kheirabadi, Patrick G Dougherty, Kimberli J Kamer, Xiulong Shen, Nelsa L Estrella, Suresh Peddigari, Anushree Pathak, Sara L Blake, Emmanuelle Sizensky, Carmen Del Genio, Arti B Gaur, Mohanraj Dhanabal, Mahasweta Girgenrath, Natarajan Sethuraman, Ziqing Qian

Faculty, Staff and Student Publications

Biological therapeutic agents are highly targeted and potent but limited in their ability to reach intracellular targets. These limitations often necessitate high therapeutic doses and can be associated with less-than-optimal therapeutic activity. One promising solution for therapeutic agent delivery is use of cell-penetrating peptides. Canonical cell-penetrating peptides, however, are limited by low efficiencies of cellular uptake and endosomal escape, minimal proteolytic stability, and toxicity. To overcome these limitations, we designed a family of proprietary cyclic cell-penetrating peptides that form the core of our endosomal escape vehicle technology capable of delivering therapeutic agent-conjugated cargo intracellularly. We demonstrated the therapeutic potential of …

Argininosuccinate Lyase Deficiency Causes Blood-Brain Barrier Disruption Via Nitric Oxide-Mediated Dysregulation Of Claudin Expression, Jordan Kho, Urszula Polak, Ming-Ming Jiang, John D Odom, Jill V Hunter, Saima M Ali, Lindsay C Burrage, Sandesh Cs Nagamani, Robia G Pautler, Hannah P Thompson, Akihiko Urayama, Zixue Jin, Brendan Lee

Faculty, Staff and Student Publications

Nitric oxide (NO) is a critical signaling molecule that has been implicated in the pathogenesis of neurocognitive diseases. Both excessive and insufficient NO production have been linked to pathology. Previously, we have shown that argininosuccinate lyase deficiency (ASLD) is a novel model system to investigate cell-autonomous, nitric oxide synthase-dependent NO deficiency. Humans with ASLD are at increased risk for developing hyperammonemia due to a block in ureagenesis. However, natural history studies have shown that individuals with ASLD have multisystem disease including neurocognitive deficits that can be independent of ammonia. Here, using ASLD as a model of NO deficiency, we investigated …