Neurosciences Commons^™

Methyl-Branched Liposomes As A Depot For Sustained Drug Delivery, Yang Li, Rachelle Shao, Claire A Ostertag-Hill, Matthew Torre, Ran Yan, Daniel S Kohane

Duncan NRI Faculty and Staff Publications

Inadequate drug loading and control of payload leakage limit the duration of the effect of liposomal drug carriers and may cause toxicity. Here, we report a liposome system as a depot for sustained drug delivery whose design is inspired by the low permeability of Archaeal membranes to protons and solutes. Incorporating methyl-branched phospholipids into lipid bilayers decreased payload diffusion across liposomal membranes, thereby enhancing the drug load capacity by 10-16% and reducing the release of small molecules in the first 24 h by 40-48%. The in vivo impact of this approach was demonstrated by injection at the sciatic nerve. Methyl-branched …

Tyramine And Its Amtyr1 Receptor Modulate Attention In Honey Bees (Apis Mellifera), Joseph S. Latshaw, Reece E. Mazade, Mary Petersen, Julie A. Mustard, Irina Sinakevitch, Lothar Wissler, Xiaojiao Guo, Chelsea Cook, Hong Lei, Brian Smith

School of Integrative Biological & Chemical Sciences Faculty Publications

Animals must learn to ignore stimuli that are irrelevant to survival and attend to ones that enhance survival. When a stimulus regularly fails to be associated with an important consequence, subsequent excitatory learning about that stimulus can be delayed, which is a form of nonassociative conditioning called ‘latent inhibition’. Honey bees show latent inhibition toward an odor they have experienced without association with food reinforcement. Moreover, individual honey bees from the same colony differ in the degree to which they show latent inhibition, and these individual differences have a genetic basis. To investigate the mechanisms that underly individual differences in …

Maxsim: Multi-Angle-Crossing Structured Illumination Microscopy With Height-Controlled Mirror For 3d Topological Mapping Of Live Cells, Pedro Felipe Gardeazabal Rodriguez, Yigal Lilach, Abhijit Ambegaonkar, Teresa Vitali, Haani Jafri, Hae Won Sohn, Matthew B. Dalva, Susan Pierce, Inhee Chung

Department of Neuroscience Faculty Papers

Mapping 3D plasma membrane topology in live cells can bring unprecedented insights into cell biology. Widefield-based super-resolution methods such as 3D-structured illumination microscopy (3D-SIM) can achieve twice the axial ( ~ 300 nm) and lateral ( ~ 100 nm) resolution of widefield microscopy in real time in live cells. However, twice-resolution enhancement cannot sufficiently visualize nanoscale fine structures of the plasma membrane. Axial interferometry methods including fluorescence light interference contrast microscopy and its derivatives (e.g., scanning angle interference microscopy) can determine nanoscale axial locations of proteins on and near the plasma membrane. Thus, by combining super-resolution lateral imaging of 2D-SIM …

A Preliminary Timeline Of The Midbrain Development In The Monodelphis Domestica Animal Model, Ismael Perez, John L. Vandeberg, Mario Gil

Research Colloquium

Introduction: The Brazilian short-tailed opossum (Monodelphis Domestica) is an understudied animal model compared to the Mus musculus that has been identified as a perfect candidate to study neurodevelopment (Baggott, L. & Moore, H., 1990). What makes the Monodelphis Domestica a perfect specimen for neurodevelopment is that the embryo develops outside the pouch of the mother providing easy noninvasive access to track changes across different developmental stages (Mate et al., 1994).

Objective: The objective of the study is to compare the area and volume in the development of the Monodelphis’s midbrain across three different developmental stages. Our research is beneficial because …

The Neuroimmune Regulation And Potential Therapeutic Strategies Of Optic Pathway Glioma, Khushboo Irshad, Yu-Kai Huang, Paul Rodriguez, Jung Lo, Benjamin E Aghoghovwia, Yuan Pan, Kun-Che Chang

Faculty, Staff and Student Publications

Optic pathway glioma (OPG) is one of the causes of pediatric visual impairment. Unfortunately, there is as yet no cure for such a disease. Understanding the underlying mechanisms and the potential therapeutic strategies may help to delay the progression of OPG and rescue the visual morbidities. Here, we provide an overview of preclinical OPG studies and the regulatory pathways controlling OPG pathophysiology. We next discuss the role of microenvironmental cells (neurons, T cells, and tumor-associated microglia and macrophages) in OPG development. Last, we provide insight into potential therapeutic strategies for treating OPG and promoting axon regeneration.

Eeg Functional Connectivity In Infants At Elevated Familial Likelihood For Autism Spectrum Disorder, Christian O'Reilly, Scott Huberty, Stefon Van Noordt, James Desjardins, Nicky Wright, Julie Scorah, Sara Jane Webb, Mayada Elsabbagh, Basis Team

Publications

Background

Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy.

Methods

We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life. EEG was recorded at 6 and 12 months of age in infants at typical (N = 92) or elevated likelihood for ASD (N = 90), determined by the presence of an older sibling with ASD. We computed the functional connectivity between …

Dissecting The Daily Feeding Pattern: Peripheral Clock/Cycle Generate The Feeding/Fasting Episodes And Neuronal Molecular Clocks Synchronize Them, Akiko Maruko, Koichi M Iijima, Kanae Ando

Department of Neuroscience Faculty Papers

A 24-h rhythm of feeding behavior, or synchronized feeding/fasting episodes during the day, is crucial for survival. Internal clocks and light input regulate rhythmic behaviors, but how they generate feeding rhythms is not fully understood. Here we aimed to dissect the molecular pathways that generate daily feeding patterns. By measuring the semidiurnal amount of food ingested by single flies, we demonstrate that the generation of feeding rhythms under light:dark conditions requires quasimodo (qsm) but not molecular clocks. Under constant darkness, rhythmic feeding patterns consist of two components: CLOCK (CLK) in digestive/metabolic tissues generating feeding/fasting episodes, and the …

Comparative Genomic Landscape Of Urothelial Carcinoma Of The Bladder Among Patients Of East And South Asian Genomic Ancestry, Taylor Peak, Philippe E Spiess, Roger Li, Petros Grivas, Andrea Necchi, Dean Pavlick, Richard S P Huang, Douglas Lin, Natalie Danziger, Joseph M Jacob, Gennady Bratslavsky, Jeffrey S Ross

Faculty, Staff and Student Publications

BACKGROUND: Despite the low rate of urothelial carcinoma of the bladder (UCB) in patients of South Asian (SAS) and East Asian (EAS) descent, they make up a significant portion of the cases worldwide. Nevertheless, these patients are largely under-represented in clinical trials. We queried whether UCB arising in patients with SAS and EAS ancestry would have unique genomic features compared to the global cohort.

METHODS: Formalin-fixed, paraffin-embedded tissue was obtained for 8728 patients with advanced UCB. DNA was extracted and comprehensive genomic profiling was performed. Ancestry was classified using a proprietary calculation algorithm. Genomic alterations (GAs) were determined using a …

Specialized Astrocytes Mediate Glutamatergic Gliotransmission In The Cns, Roberta De Ceglia, Ada Ledonne, David Gregory Litvin, Barbara Lykke Lind, Giovanni Carriero, Emanuele Claudio Latagliata, Erika Bindocci, Maria Amalia Di Castro, Iaroslav Savtchouk, Ilaria Vitali, Anurag Ranjak, Mauro Congiu, Tara Canonica, William Wisden, Kenneth Harris, Manuel Mameli, Nicola Mercuri, Ludovic Telley, Andrea Volterra

Biomedical Sciences Faculty Research and Publications

Multimodal astrocyte–neuron communications govern brain circuitry assembly and function. For example, through rapid glutamate release, astrocytes can control excitability, plasticity and synchronous activity of synaptic networks, while also contributing to their dysregulation in neuropsychiatric conditions. For astrocytes to communicate through fast focal glutamate release, they should possess an apparatus for Ca2+-dependent exocytosis similar to neurons. However, the existence of this mechanism has been questioned owing to inconsistent data and a lack of direct supporting evidence. Here we revisited the astrocyte glutamate exocytosis hypothesis by considering the emerging molecular heterogeneity of astrocytes and using molecular, bioinformatic and imaging approaches, together with …

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 …

Chromosomal Aberrations In Pediatric Patients With Moderate/Severe Developmental Delay/Intellectual Disability With Abundant Phenotypic Heterogeneities: A Single-Center Study, Dan Wu, Yi Wu, Yulong Lan, Shaocong Lan, Zhiwei Zhong, Duo Li, Zexin Zheng, Hongwu Wang, Lian Ma

Research outputs 2022 to 2026

Background: This study aimed to examine the clinical usefulness of chromosome microarray (CMA) for selective implementation in patients with unexplained moderate or severe developmental delay/intellectual disability (DD/ID) and/or combined with different dysphonic features in the Han Chinese population. Methods: We retrospectively analyzed data on 122 pediatric patients with unexplained isolated moderate/severe DD/ID with or without autism spectrum disorders, epilepsy, dystonia, and congenital abnormalities from a single-center neurorehabilitation clinic in southern China. Results: A total of 46 probands (37.7%) had abnormal CMA results among the 122 study patients. With the exclusion of aneuploidies, uniparental disomies, and multiple homozygotes, 37 patients harbored …

The Influence Of Baseline Sleep On Exercise-Induced Cognitive Change In Cognitively Unimpaired Older Adults: A Randomised Clinical Trial, Kelsey R. Sewell, Stephanie R. Rainey-Smith, Jeremiah Peiffer, Hamid R. Sohrabi, James Doecke, Natalie J. Frost, Shaun J. Markovic, Kirk Erickson, Belinda M. Brown

Research outputs 2022 to 2026

Objectives: Observational studies consistently demonstrate that physical activity is associated with elevated cognitive function, however, there remains significant heterogeneity in cognitive outcomes from randomized exercise interventions. Individual variation in sleep behaviours may be a source of variability in the effectiveness of exercise-induced cognitive change, however this has not yet been investigated. The current study aimed to (1) investigate the influence of a 6-month exercise intervention on sleep, assessed pre- and post-intervention and, (2) investigate whether baseline sleep measures moderate exercise-induced cognitive changes. Methods: We utilised data from the Intense Physical Activity and Cognition (IPAC) study (n = 89), a 6-month …

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 …

The Microtubule Quartet Protein Snap1 In Trypanosoma Brucei Facilitates Flagellum And Cell Division Plane Positioning By Promoting Basal Body Segregation, Martin Carbo-Tano, Mathilde Lapoix, Xinyu Jia, Olivier Thouvenin, Marco Pascucci, François Auclair, Feng B Quan, Shahad Albadri, Vernie Aguda, Younes Farouj, Elizabeth M C Hillman, Ruben Portugues, Filippo Del Bene, Tod R Thiele, Réjean Dubuc, Claire Wyart

Faculty, Staff and Student Publications

The mesencephalic locomotor region (MLR) is a brain stem area whose stimulation triggers graded forward locomotion. How MLR neurons recruit downstream vsx2+ (V2a) reticulospinal neurons (RSNs) is poorly understood. Here, to overcome this challenge, we uncovered the locus of MLR in transparent larval zebrafish and show that the MLR locus is distinct from the nucleus of the medial longitudinal fasciculus. MLR stimulations reliably elicit forward locomotion of controlled duration and frequency. MLR neurons recruit V2a RSNs via projections onto somata in pontine and retropontine areas, and onto dendrites in the medulla. High-speed volumetric imaging of neuronal activity reveals that …

Can Craniosynostosis Be Diagnosed On Physical Examination? A Retrospective Review, Carmen A Zavala, Laura A Zima, Matthew R Greives, Stephen A Fletcher, Manish N Shah, Brandon A Miller, David I Sandberg, Phuong D Nguyen

Faculty, Staff and Student Publications

Craniosynostosis is a developmental craniofacial defect in which one or more sutures of the skull fuse together prematurely. Uncorrected craniosynostosis may have serious complications including elevated intracranial pressure, developmental delay, and blindness. Proper diagnosis of craniosynostosis requires a physical examination of the head with assessment for symmetry and palpation of sutures for prominence. Often, if craniosynostosis is suspected, computed tomography (CT) imaging will be obtained. Recent literature has posited that this is unnecessary. This study aims to address whether physical examination alone is sufficient for the diagnosis and treatment planning of single suture craniosynostosis. Between 2015 and 2022, the Divisions …

The Role Of Zinc In Psd-95 Palmitoyl Modification, Luis F. Acosta, Lili Guerra, Safiya Syed, Ivonn Ruvalcaba, Yonghong Zhang, Xiaoqian Fang

Research Symposium

Postsynaptic density-95 (PSD-95) is a membrane-associated guanylate kinase that mediates localization of receptors in the excitatory postsynaptic density. It has been reported that PSD-95 mediates postsynaptic localization of NMDA receptors and anchors postsynaptic AMPAR receptors mainly through its postsynaptic membrane targeting by its N-terminal palmitoylation. Recent studies have shown that Ca2+/calmodulin blocks palmitoylation of PSD-95 by binding at the N-terminus of PSD-95, which promotes dissociation of PSD-95 from the postsynaptic membrane and causes loss of surface AMPARs in cultured neurons. Another metal ion zinc is found in various areas of the brain. As an endogenous neuromodulator, zinc plays a role …

Fornix Volumetric Increase During Aging Associates To Microglia Activation Leading To Defective Cognitive Performance, Marcela Cárdenas Tueme, Luis Ángel Trujillo-Villarreal, Victor Ramírez-Amaya, Eduardo Garza-Villarreal, Alberto Camacho-Morales, Diana Reséndez-Pérez

Research Symposium

Background: Ageing displays a low-grade pro-inflammatory profile in blood and brain. It has been documented proinflammatory cytokines accumulation leading to neuroinflammation during aging. Aged brains integrate pro inflammatory cytokines accumulation, active microglia and volumetric changes which correlates with defective cognitive performance and neurodegeneration.

Methods: Mice from 2-,12- and 20-months-old of age were submitted to different memory tests: Y-maze, Barnes maze, object location test and object location test. Afterwards, we performed structural MRI to evaluate macrostructural changes related to memory and learning regions. Following this, we also evaluated in peripheral blood and in brain tissue the presence of pro-inflammatory cytokines …

Adaptive Octree Meshes For Simulation Of Extracellular Electrophysiology, Christopher Bc Girard, Dong Song

Engineering Faculty Articles and Research

Objective. The interaction between neural tissues and artificial electrodes is crucial for understanding and advancing neuroscientific research and therapeutic applications. However, accurately modeling this space around the neurons rapidly increases the computational complexity of neural simulations. Approach. This study demonstrates a dynamically adaptive simulation method that greatly accelerates computation by adjusting spatial resolution of the simulation as needed. Use of an octree structure for the mesh, in combination with the admittance method for discretizing conductivity, provides both accurate approximation and ease of modification on-the-fly. Main results. In tests of both local field potential estimation and multi-electrode stimulation, dynamically adapted meshes …

Years Of Education And Total Intracranial Volume: A Longitudinal Study, Okechukwu C. Erinne

Research Symposium

Background: Education is one of the factors that contribute to a higher brain reserve. Based on the brain reserve hypothesis, the greater the brain reserve, the less likely it is to develop a neurocognitive disorder, such as dementia.

Methods: Data for this study were obtained from the Open Access Series of Imaging Studies (OASIS) longitudinal magnetic resonance imaging (MRI) data in nondemented and demented adults. There was a total of 150 right-handed participants and 373 imaging sessions, with an average duration of 719 days between visits. The primary outcome was estimated total intracranial volume (eTIV). Multivariable longitudinal regression was used …