Neurosciences Commons^™

Stereo-Eeg-Guided Network Modulation For Psychiatric Disorders: Surgical Considerations, Sameer A Sheth, Ben Shofty, Anusha Allawala, Jiayang Xiao, Joshua A Adkinson, Raissa K Mathura, Victoria Pirtle, John Myers, Denise Oswalt, Nicole R Provenza, Nisha Giridharan, Angela M Noecker, Garrett P Banks, Ron Gadot, Ricardo A Najera, Adrish Anand, Ethan Devara, Huy Dang, Eleonora Bartoli, Andrew Watrous, Jeffrey Cohn, David Borton, Sanjay J Mathew, Cameron C Mcintyre, Wayne Goodman, Kelly Bijanki, Nader Pouratian

Faculty, Staff and Students Publications

BACKGROUND: Deep brain stimulation (DBS) and other neuromodulatory techniques are being increasingly utilized to treat refractory neurologic and psychiatric disorders.

OBJECTIVE: /Hypothesis: To better understand the circuit-level pathophysiology of treatment-resistant depression (TRD) and treat the network-level dysfunction inherent to this challenging disorder, we adopted an approach of inpatient intracranial monitoring borrowed from the epilepsy surgery field.

METHODS: We implanted 3 patients with 4 DBS leads (bilateral pair in both the ventral capsule/ventral striatum and subcallosal cingulate) and 10 stereo-electroencephalography (sEEG) electrodes targeting depression-relevant network regions. For surgical planning, we used an interactive, holographic visualization platform to appreciate the 3D anatomy …

Behavioral Improvements Following Lesion Resection For Pediatric Epilepsy: Pediatric Psychosurgery?, Huy Dang, Abdul Basit Khan, Nisha Gadgil, Himanshu Sharma, Cristina Trandafir, Fatema Malbari, Howard L Weiner

Faculty, Staff and Students Publications

Introduction: Resection of brain lesions associated with refractory epilepsy to achieve seizure control is well accepted. However, concurrent behavioral effects of these lesions such as changes in mood, personality, and cognition and the effects of surgery on behavior have not been well characterized. We describe 5 such children with epileptogenic lesions and significant behavioral abnormalities which improved after surgery.

Case descriptions: Five children (ages 3-14 years) with major behavioral abnormalities and lesional epilepsy were identified and treated at our center. Behavioral problems included academic impairment, impulsivity, self-injurious behavior, and decreased social interaction with diagnoses of ADHD, oppositional defiant disorder, and …

Sphingolipids In Neurodegenerative Diseases, Xueyang Pan, Debdeep Dutta, Shenzhao Lu, Hugo J Bellen

Faculty, Staff and Students Publications

Neurodegenerative Diseases (NDDs) are a group of disorders that cause progressive deficits of neuronal function. Recent evidence argues that sphingolipid metabolism is affected in a surprisingly broad set of NDDs. These include some lysosomal storage diseases (LSDs), hereditary sensory and autonomous neuropathy (HSAN), hereditary spastic paraplegia (HSP), infantile neuroaxonal dystrophy (INAD), Friedreich’s ataxia (FRDA), as well as some forms of amyotrophic lateral sclerosis (ALS) and Parkinson’s disease (PD). Many of these diseases have been modeled in Drosophila melanogaster and are associated with elevated levels of ceramides. Similar changes have also been reported in vertebrate cells and mouse models. Here, we …

Editorial: Surgical Techniques For The Management Of Pain, Anthony K Allam, Ashwin Viswanathan, Jason M Schwalb, Parag G Patil, M Benjamin Larkin

Faculty, Staff and Students Publications

No abstract provided.

Stereo-Eeg-Guided Network Modulation For Psychiatric Disorders: Interactive Holographic Planning, Angela M Noecker, Jeffrey Mlakar, Kelly R Bijanki, Mark A Griswold, Nader Pouratian, Sameer A Sheth, Cameron C Mcintyre

Faculty, Staff and Students Publications

Background: Connectomic modeling studies are expanding understanding of the brain networks that are modulated by deep brain stimulation (DBS) therapies. However, explicit integration of these modeling results into prospective neurosurgical planning is only beginning to evolve. One challenge of employing connectomic models in patient-specific surgical planning is the inherent 3D nature of the results, which can make clinically useful data integration and visualization difficult.

Methods: We developed a holographic stereotactic neurosurgery research tool (HoloSNS) that integrates patient-specific brain models into a group-based visualization environment for interactive surgical planning using connectomic hypotheses. HoloSNS currently runs on the HoloLens 2 platform and …

Imaging Synaptic Density In Depression, Sophie E Holmes, Chadi Abdallah, Irina Esterlis

Faculty, Staff and Students Publications

Major depressive disorder is a prevalent and heterogeneous disorder with treatment resistance in at least 50% of individuals. Most of the initial studies focused on the monoamine system; however, recently other mechanisms have come under investigation. Specific to the current issue, studies show synaptic involvement in depression. Other articles in this issue report on reductions in synaptic density, dendritic spines, boutons and glia associated with stress and depression. Importantly, it appears that some drugs (e.g., ketamine) may lead to rapid synaptic restoration or synaptogenesis. Direct evidence for this comes from preclinical work. However, neuroimaging studies, such as magnetic resonance imaging …

Kdm6b Variants May Contribute To The Pathophysiology Of Human Cerebral Folate Deficiency, Xiao Han, Xuanye Cao, Robert M Cabrera, Paula Andrea Pimienta Ramirez, Cuilian Zhang, Vincent T Ramaekers, Richard H Finnell, Yunping Lei

Faculty, Staff and Students Publications

(1) Background: The genetic etiology of most patients with cerebral folate deficiency (CFD) remains poorly understood. KDM6B variants were reported to cause neurodevelopmental diseases; however, the association between KDM6B and CFD is unknown; (2) Methods: Exome sequencing (ES) was performed on 48 isolated CFD cases. The effect of KDM6B variants on KDM6B protein expression, Histone H3 lysine 27 epigenetic modification and FOLR1 expression were examined in vitro. For each patient, serum FOLR1 autoantibodies were measured; (3) Results: Six KDM6B variants were identified in five CFD patients, which accounts for 10% of our CFD cohort cases. Functional experiments indicated that these …

White Matter Correlates Of Domain-Specific Working Memory, Autumn Horne, Junhua Ding, Tatiana T Schnur, Randi C Martin

Faculty, Staff and Student Publications

Prior evidence suggests domain-specific working memory (WM) buffers for maintaining phonological (i.e., speech sound) and semantic (i.e., meaning) information. The phonological WM buffer's proposed location is in the left supramarginal gyrus (SMG), whereas semantic WM has been related to the left inferior frontal gyrus (IFG), the middle frontal gyrus (MFG), and the angular gyrus (AG). However, less is known about the white matter correlates of phonological and semantic WM. We tested 45 individuals with left hemisphere brain damage on single word processing, phonological WM, and semantic WM tasks and obtained T1 and diffusion weighted neuroimaging. Virtual dissections were performed for …

Xcvatr: Detection And Characterization Of Variant Impact On The Embeddings Of Single -Cell And Bulk Rna-Sequencing Samples, Arif Harmanci, Akdes Serin Harmanci, Tiemo J Klisch, Akash J Patel

Duncan NRI Faculty and Staff Publications

Background: RNA-sequencing has become a standard tool for analyzing gene activity in bulk samples and at the single-cell level. By increasing sample sizes and cell counts, this technique can uncover substantial information about cellular transcriptional states. Beyond quantification of gene expression, RNA-seq can be used for detecting variants, including single nucleotide polymorphisms, small insertions/deletions, and larger variants, such as copy number variants. Notably, joint analysis of variants with cellular transcriptional states may provide insights into the impact of mutations, especially for complex and heterogeneous samples. However, this analysis is often challenging due to a prohibitively high number of variants and …

Frequency And Burden Of Neurological Manifestations Upon Hospital Presentation In Covid-19 Patients: Findings From A Large Brazilian Cohort, Milena Soriano Marcolino, Fernando Anschau, Luciane Kopittke, Magda Carvalho Pires, Izabela Guimarães Barbosa, Daniella Nunes Pereira, Lucas Emanuel Ferreira Ramos, Luís Fernando Israel Assunção, André Soares De Moura Costa, Matheus Carvalho Alves Nogueira, Helena Duani, Karina Paula Medeiros Prado Martins, Leila Beltrami Moreira, Carla Thais Cândida Alves Da Silva, Neimy Ramos De Oliveira, Patricia Klarmann Ziegelmann, Milton Henriques Guimarães-Júnior, Mauro Oscar Soares De Souza Lima, Rubia Laura Oliveira Aguiar, Luanna Silva Monteiro Menezes, Talita Fischer Oliveira, Maíra Dias Souza, Bárbara Lopes Farace, Christiane Corrêa Rodrigues Cimini, Amanda De Oliveira Maurílio, Silvana Mangeon Mereilles Guimarães, Silvia Ferreira Araújo, Guilherme Fagundes Nascimento, Daniel Vitório Silveira, Karen Brasil Ruschel, Thainara Conceição De Oliveira, Alexandre Vargas Schwarzbold, Luiz Antônio Nasi, Maiara Anschau Floriani, Veridiana Baldon Dos Santos, Carolina Marques Ramos, Joice Coutinho De Alvarenga, Ana Luiza Bahia Alves Scotton, Euler Roberto Fernandes Manenti, Gabriela Petry Crestani, Joanna D'Arc Lyra Batista, Daniela Ponce, Juliana Machado-Rugolo, Adriana Falangola Benjamin Bezerra, Petrônio José De Lima Martelli, Heloisa Reniers Vianna, Luís César De Castro, Cássia Regina Gotler Medeiros, Giovanna Grunewald Vietta, Elayne Crestani Pereira, José Miguel Chatkin, Mariana Frizzo De Godoy, Polianna Delfino-Pereira, Antonio Lucio Teixeira

Faculty, Staff and Student Publications

BACKGROUND: Scientific data regarding the prevalence of COVID-19 neurological manifestations and prognosis in Latin America countries is still lacking. Therefore, the study aims to understand neurological manifestations of SARS-CoV 2 infection and outcomes in the Brazilian population.

METHODS: This study is part of the Brazilian COVID-19 Registry, a multicentric cohort, including data from 37 hospitals. For the present analysis, patients were grouped according to the presence of reported symptoms (i.e., headache; anosmia and ageusia; syncope and dizziness) vs. clinically-diagnosed neurological manifestations (clinically-defined neurological syndrome: neurological signs or diagnoses captured by clinical evaluation) and matched with patients without neurological manifestations by …

Tiam1-Mediated Synaptic Plasticity Underlies Comorbid Depression-Like And Ketamine Antidepressant-Like Actions In Chronic Pain, Qin Ru, Yungang Lu, Ali Bin Saifullah, Francisco A Blanco, Changqun Yao, Juan P Cata, De-Pei Li, Kimberley F Tolias, Lingyong Li

Faculty, Staff and Students Publications

Chronic pain often leads to depression, increasing patient suffering and worsening prognosis. While hyperactivity of the anterior cingulate cortex (ACC) appears to be critically involved, the molecular mechanisms underlying comorbid depressive symptoms in chronic pain remain elusive. T cell lymphoma invasion and metastasis 1 (Tiam1) is a Rac1 guanine nucleotide exchange factor (GEF) that promotes dendrite, spine, and synapse development during brain development. Here, we show that Tiam1 orchestrates synaptic structural and functional plasticity in ACC neurons via actin cytoskeleton reorganization and synaptic N-methyl-d-aspartate receptor (NMDAR) stabilization. This Tiam1-coordinated synaptic plasticity underpins ACC hyperactivity and drives chronic pain-induced depressive-like behaviors. …

Detection Of Stroke With Retinal Microvascular Density And Self-Supervised Learning Using Oct-A And Fundus Imaging, Samiksha Pachade, Ivan Coronado, Rania Abdelkhaleq, Juntao Yan, Sergio Salazar-Marioni, Amanda Jagolino, Charles Green, Mozhdeh Bahrainian, Roomasa Channa, Sunil A Sheth, Luca Giancardo

Faculty, Staff and Student Publications

Acute cerebral stroke is a leading cause of disability and death, which could be reduced with a prompt diagnosis during patient transportation to the hospital. A portable retina imaging system could enable this by measuring vascular information and blood perfusion in the retina and, due to the homology between retinal and cerebral vessels, infer if a cerebral stroke is underway. However, the feasibility of this strategy, the imaging features, and retina imaging modalities to do this are not clear. In this work, we show initial evidence of the feasibility of this approach by training machine learning models using feature engineering …

Contributions Of Semantic And Phonological Working Memory To Narrative Language Independent Of Single Word Production: Evidence From Acute Stroke, Rachel Zahn, Tatiana T Schnur, Randi C Martin

Faculty, Staff and Student Publications

Neuropsychological case studies have provided evidence that individuals with semantic, but not phonological, working memory (WM) deficits have difficulty producing phrases containing several content words. These findings supported the claim of a phrasal scope of planning at the grammatical formulation stage of production, where semantic WM supports the maintenance of lexical-semantic representations as they are inserted into slots in phrasal constituents. Recent narrative production results for individuals at the acute stage of stroke supported the role for semantic WM in phrasal elaboration while suggesting a role for phonological WM at a subsequent phonological encoding stage in supporting fluent, rapid speech. …

Active Dna Demethylation Promotes Cell Fate Specification And The Dna Damage Response, Dongpeng Wang, Wei Wu, Elsa Callen, Raphael Pavani, Nicholas Zolnerowich, Srikanth Kodali, Dali Zong, Nancy Wong, Santiago Noriega, William J Nathan, Gabriel Matos-Rodrigues, Raj Chari, Michael J Kruhlak, Ferenc Livak, Michael Ward, Keith Caldecott, Bruno Di Stefano, André Nussenzweig

Faculty, Staff and Students Publications

Neurons harbor high levels of single-strand DNA breaks (SSBs) that are targeted to neuronal enhancers, but the source of this endogenous damage remains unclear. Using two systems of postmitotic lineage specification-induced pluripotent stem cell-derived neurons and transdifferentiated macrophages-we show that thymidine DNA glycosylase (TDG)-driven excision of methylcytosines oxidized with ten-eleven translocation enzymes (TET) is a source of SSBs. Although macrophage differentiation favors short-patch base excision repair to fill in single-nucleotide gaps, neurons also frequently use the long-patch subpathway. Disrupting this gap-filling process using anti-neoplastic cytosine analogs triggers a DNA damage response and neuronal cell death, which is dependent on TDG. …

Reorganization Of The Functional Connectome From Rest To A Visual Perception Task In Schizophrenia And Bipolar Disorder, Philipp Riedel, Junghee Lee, Christopher G Watson, Amy M Jimenez, Eric A Reavis, Michael F Green

Faculty, Staff and Student Publications

Functional connectome organization is altered in schizophrenia (SZ) and bipolar disorder (BD). However, it remains unclear whether network reorganization during a task relative to rest is also altered in these disorders. This study examined connectome organization in patients with SZ (N = 43) and BD (N = 42) versus healthy controls (HC; N = 39) using fMRI data during a visual object-perception task and at rest. Graph analyses were conducted for the whole-brain network using indices selected a priori: three reflecting network segregation (clustering coefficient, local efficiency, modularity), two reflecting integration (characteristic path length, global efficiency). Group differences were limited …

Implementation Of Systematic Safety Checklists In A Neurocritical Care Unit: A Quality Improvement Study, César E Escamilla-Ocañas, Gabriel Torrealba-Acosta, Pitchaiah Mandava, Muhammad Suhaib Qasim, Bárbara Gutiérrez-Flores, Eric Bershad, Mohammad Hirzallah, Chethan P Venkatasubba Rao, Rahul Damani

Faculty, Staff and Students Publications

Background and objectives: Structured and systematised checklists have been shown to prevent complications and improve patient care. We evaluated the implementation of systematic safety checklists in our neurocritical care unit (NCCU) and assessed its effect on patient outcomes.

Design/methods: This quality improvement project followed a Plan-Do-Study-Act (PDSA) methodology. A checklist for medication reconciliation, thromboembolic prophylaxis, glycaemic control, daily spontaneous awakening, breathing trial, diet, catheter/lines duration monitoring and antibiotics de-escalation was implemented during daily patient rounds. Main outcomes included the rate of new infections, mortality and NCCU-length of stay (LOS). Intervened patients were compared with historical controls after propensity score and …

K27m In Canonical And Noncanonical H3 Variants Occurs In Distinct Oligodendroglial Cell Lineages In Brain Midline Gliomas, Selin Jessa, Abdulshakour Mohammadnia, Ashot S Harutyunyan, Maud Hulswit, Srinidhi Varadharajan, Hussein Lakkis, Nisha Kabir, Zahedeh Bashardanesh, Steven Hébert, Damien Faury, Maria C Vladoiu, Samantha Worme, Marie Coutelier, Brian Krug, Augusto Faria Andrade, Manav Pathania, Andrea Bajic, Alexander G Weil, Benjamin Ellezam, Jeffrey Atkinson, Roy W R Dudley, Jean-Pierre Farmer, Sebastien Perreault, Benjamin A Garcia, Valérie Larouche, Mathieu Blanchette, Livia Garzia, Aparna Bhaduri, Keith L Ligon, Pratiti Bandopadhayay, Michael D Taylor, Stephen C Mack, Nada Jabado, Claudia L Kleinman

Faculty, Staff and Students Publications

Canonical (H3.1/H3.2) and noncanonical (H3.3) histone 3 K27M-mutant gliomas have unique spatiotemporal distributions, partner alterations and molecular profiles. The contribution of the cell of origin to these differences has been challenging to uncouple from the oncogenic reprogramming induced by the mutation. Here, we perform an integrated analysis of 116 tumors, including single-cell transcriptome and chromatin accessibility, 3D chromatin architecture and epigenomic profiles, and show that K27M-mutant gliomas faithfully maintain chromatin configuration at developmental genes consistent with anatomically distinct oligodendrocyte precursor cells (OPCs). H3.3K27M thalamic gliomas map to prosomere 2-derived lineages. In turn, H3.1K27M ACVR1-mutant pontine gliomas uniformly mirror early ventral …

Author Correction: Entorhinal Cortex Directs Learning-Related Changes In Ca1 Representations, Christine Grienberger, Jeffrey C Magee

Faculty, Staff and Students Publications

No abstract provided.

A Minimal Role For Synonymous Variation In Human Disease, Ryan S Dhindsa, Quanli Wang, Dimitrios Vitsios, Oliver S Burren, Fengyuan Hu, James E Dicarlo, Leonid Kruglyak, Daniel G Macarthur, Matthew E Hurles, Slavé Petrovski

Duncan NRI Faculty and Staff Publications

Synonymous mutations change the DNA sequence of a gene without affecting the amino acid sequence of the encoded protein. Although some synonymous mutations can affect RNA splicing, translational efficiency, and mRNA stability, studies in human genetics, mutagenesis screens, and other experiments and evolutionary analyses have repeatedly shown that most synonymous variants are neutral or only weakly deleterious, with some notable exceptions. Based on a recent study in yeast, there have been claims that synonymous mutations could be as important as nonsynonymous mutations in causing disease, assuming the yeast findings hold up and translate to humans. Here, we argue that there …

Propranolol Modulates Cerebellar Circuit Activity And Reduces Tremor., Joy Zhou, Meike E Van Der Heijden, Luis E Salazar Leon, Tao Lin, Lauren N Miterko, Dominic J Kizek, Ross M Perez, Matea Pavešković, Amanda M Brown, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Tremor is the most common movement disorder. Several drugs reduce tremor severity, but no cures are available. Propranolol, a β-adrenergic receptor blocker, is the leading treatment for tremor. However, the in vivo circuit mechanisms by which propranolol decreases tremor remain unclear. Here, we test whether propranolol modulates activity in the cerebellum, a key node in the tremor network. We investigated the effects of propranolol in healthy control mice and Car8^wdl/wdl mice, which exhibit pathophysiological tremor and ataxia due to cerebellar dysfunction. Propranolol reduced physiological tremor in control mice and reduced pathophysiological tremor in Car8^wdl/wdl mice to control levels. …

Neurobehavioral Deficits And A Progressive Ictogenesis In The Tetrodotoxin Model Of Epileptic Spasms, John T Le, Carlos J Ballester-Rosado, James D Frost, John W Swann

Duncan NRI Faculty and Staff Publications

Objective: Our goal was to determine whether animals with a history of epileptic spasms have learning and memory deficits. We also used continuous (24/7) long-term electroencephalographic (EEG) recordings to evaluate the evolution of epileptiform activity in the same animals over time.

Methods: Object recognition memory and object location memory tests were undertaken, as well as a matching to place water maze test that evaluated working memory. A retrospective analysis was undertaken of long-term video/EEG recordings from rats with epileptic spasms. The frequency and duration of the ictal events of spasms were quantified.

Results: Rats with a history of epileptic spasms …

Development Of Myelinating Glia: An Overview, Carlo D Cristobal, Hyun Kyoung Lee

Duncan NRI Faculty and Staff Publications

Myelin is essential to nervous system function, playing roles in saltatory conduction and trophic support. Oligodendrocytes (OLs) and Schwann cells (SCs) form myelin in the central and peripheral nervous systems respectively and follow different developmental paths. OLs are neural stem-cell derived and follow an intrinsic developmental program resulting in a largely irreversible differentiation state. During embryonic development, OL precursor cells (OPCs) are produced in distinct waves originating from different locations in the central nervous system, with a subset developing into myelinating OLs. OPCs remain evenly distributed throughout life, providing a population of responsive, multifunctional cells with the capacity to remyelinate …

Seizure Count Forecasting To Aid Diagnostic Testing In Epilepsy, Emily T Wang, Sharon Chiang, Stephen Cleboski, Vikram R Rao, Marina Vannucci, Zulfi Haneef

Faculty, Staff and Students Publications

Objective: Epilepsy monitoring unit (EMU) admissions are critical for presurgical evaluation of drug-resistant epilepsy but may be nondiagnostic if an insufficient number of seizures are recorded. Seizure forecasting algorithms have shown promise for estimating the likelihood of seizures as a binary event in individual patients, but methods to predict how many seizures will occur remain elusive. Such methods could increase the diagnostic yield of EMU admissions and help patients mitigate seizure-related morbidity. Here, we evaluated the performance of a state-space method that uses prior seizure count data to predict future counts.

Methods: A Bayesian negative-binomial dynamic linear model (DLM) was …

Hdac2 In Primary Sensory Neurons Constitutively Restrains Chronic Pain By Repressing Α2Δ-1 Expression And Associated Nmda Receptor Activity, Jixiang Zhang, Shao-Rui Chen, Meng-Hua Zhou, Daozhong Jin, Hong Chen, Li Wang, Ronald A Depinho, Hui-Lin Pan

Faculty, Staff and Student Publications

α2δ-1 (encoded by the Cacna2d1 gene) is a newly discovered NMDA receptor-interacting protein and is the therapeutic target of gabapentinoids (e.g., gabapentin and pregabalin) frequently used for treating patients with neuropathic pain. Nerve injury causes sustained α2δ-1 upregulation in the dorsal root ganglion (DRG), which promotes NMDA receptor synaptic trafficking and activation in the spinal dorsal horn, a hallmark of chronic neuropathic pain. However, little is known about how nerve injury initiates and maintains the high expression level of α2δ-1 to sustain chronic pain. Here, we show that nerve injury caused histone hyperacetylation and diminished enrichment of histone deacetylase-2 (HDAC2), …

Notch Missense Mutations In Drosophila Reveal Functions Of Specific Egf-Like Repeats In Notch Folding, Trafficking, And Signaling, Hilman Nurmahdi, Mao Hasegawa, Elzava Yuslimatin Mujizah, Takeshi Sasamura, Mikiko Inaki, Shinya Yamamoto, Tomoko Yamakawa, Kenji Matsuno

Duncan NRI Faculty and Staff Publications

Notch signaling plays various roles in cell-fate specification through direct cell–cell interactions. Notch receptors are evolutionarily conserved transmembrane proteins with multiple epidermal growth factor (EGF)-like repeats. Drosophila Notch has 36 EGF-like repeats, and while some play a role in Notch signaling, the specific functions of most remain unclear. To investigate the role of each EGF-like repeat, we used 19 previously identified missense mutations of Notch with unique amino acid substitutions in various EGF-like repeats and a transmembrane domain; 17 of these were identified through a single genetic screen. We assessed these mutants’ phenotypes in the nervous system and hindgut during …

Influence Of Data Sampling Methods On The Representation Of Neural Spiking Activity In Vivo, Meike E Van Der Heijden, Amanda M Brown, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

No abstract provided.

Region-Specific Denoising Identifies Spatial Co-Expression Patterns And Intra-Tissue Heterogeneity In Spatially Resolved Transcriptomics Data, Linhua Wang, Mirjana Maletic-Savatic, Zhandong Liu

Duncan NRI Faculty and Staff Publications

Spatially resolved transcriptomics is a relatively new technique that maps transcriptional information within a tissue. Analysis of these datasets is challenging because gene expression values are highly sparse due to dropout events, and there is a lack of tools to facilitate in silico detection and annotation of regions based on their molecular content. Therefore, we develop a computational tool for detecting molecular regions and region-based Missing value Imputation for Spatially Transcriptomics (MIST). We validate MIST-identified regions across multiple datasets produced by 10x Visium Spatial Transcriptomics, using manually annotated histological images as references. We benchmark MIST against a spatial k-nearest neighboring …

Two Neuronal Peptides Encoded From A Single Transcript Regulate Mitochondrial Complex Iii In Drosophila, Justin A Bosch, Berrak Ugur, Israel Pichardo-Casas, Jordan Rabasco, Felipe Escobedo, Zhongyuan Zuo, Ben Brown, Susan Celniker, David A Sinclair, Hugo J Bellen, Norbert Perrimon

Duncan NRI Faculty and Staff Publications

Naturally produced peptides (<100 amino acids) are important regulators of physiology, development, and metabolism. Recent studies have predicted that thousands of peptides may be translated from transcripts containing small open-reading frames (smORFs). Here, we describe two peptides in Drosophila encoded by conserved smORFs, Sloth1 and Sloth2. These peptides are translated from the same bicistronic transcript and share sequence similarities, suggesting that they encode paralogs. Yet, Sloth1 and Sloth2 are not functionally redundant, and loss of either peptide causes animal lethality, reduced neuronal function, impaired mitochondrial function, and neurodegeneration. We provide evidence that Sloth1/2 are highly expressed in neurons, imported to mitochondria, and regulate mitochondrial complex III assembly. These results suggest that phenotypic analysis of smORF genes in Drosophila can provide a wealth of information on the biological functions of this poorly characterized class of …

Clinical Significance And Potential Role Of Trimethylamine N-Oxide In Neurological And Neuropsychiatric Disorders, Sowjanya Mudimela, Narahari Koppa Vishwanath, Anilkumar Pillai, Rodrigo Morales, Sean P Marrelli, Tatiana Barichello, Vijayasree V Giridharan

Faculty, Staff and Student Publications

Research in the last three decades has attracted the attention of many scientists and industrialists on the gut microbiome and its metabolites. Among many of these metabolites, trimethylamine oxide. Dietary choline, phosphatidylcholine, carnitine, and betaine produces TMAO that with other gut metabolites such as TMA (trimethylamine), and short-chain fatty acids (SCFA) enter the circulation. Finally they reach the brain through the blood-brain barrier (BBB) where they are involved in several physiological functions such as brain development, neurogenesis, and behavior. Gut-microbiota composition is influenced by diet, lifestyle, antibiotics, and age resulting in dysbiosis. Several studies have confirmed that altered TMAO levels …

Assessing Naming Errors Using An Automated Machine Learning Approach, Tatiana T Schnur, Chia-Ming Lei

Faculty, Staff and Student Publications

OBJECTIVE: After left hemisphere stroke, 20%-50% of people experience language deficits, including difficulties in naming. Naming errors that are semantically related to the intended target (e.g., producing "violin" for picture HARP) indicate a potential impairment in accessing knowledge of word forms and their meanings. Understanding the cause of naming impairments is crucial to better modeling of language production as well as for tailoring individualized rehabilitation. However, evaluation of naming errors is typically by subjective and laborious dichotomous classification. As a result, these evaluations do not capture the degree of semantic similarity and are susceptible to lower interrater reliability because of …