Neurosciences Commons^™

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 …

Hdac6 Inhibition Reverses Cisplatin-Induced Mechanical Hypersensitivity Via Tonic Delta Opioid Receptor Signaling, Jixiang Zhang, Jazzmine M Junigan, Ronnie Trinh, Annemieke Kavelaars, Cobi J Heijnen, Peter M Grace

Faculty, Staff and Student Publications

Peripheral neuropathic pain induced by the chemotherapeutic cisplatin can persist for months to years after treatment. Histone deacetylase 6 (HDAC6) inhibitors have therapeutic potential for cisplatin-induced neuropathic pain since they persistently reverse mechanical hypersensitivity and spontaneous pain in rodent models. Here, we investigated the mechanisms underlying reversal of mechanical hypersensitivity in male and female mice by a 2 week treatment with an HDAC6 inhibitor, administered 3 d after the last dose of cisplatin. Mechanical hypersensitivity in animals of both sexes treated with the HDAC6 inhibitor was temporarily reinstated by a single injection of the neutral opioid receptor antagonist 6β-naltrexol or …

Preconditioning By Voluntary Wheel Running Attenuates Later Neuropathic Pain Via Nuclear Factor E2-Related Factor 2 Antioxidant Signaling In Rats, Suzanne M Green-Fulgham, Michael E Harland, Jayson B Ball, Jiahe Li, Michael J Lacagnina, Heather D'Angelo, Renee A Dreher, Kendal F Willcox, Sabina A Lorca, Andrew J Kwilasz, Steven F Maier, Linda R Watkins, Peter M Grace

Faculty, Staff and Student Publications

Animal and human studies have shown that exercise prior to nerve injury prevents later chronic pain, but the mechanisms of such preconditioning remain elusive. Given that exercise acutely increases the formation of free radicals, triggering antioxidant compensation, we hypothesized that voluntary running preconditioning would attenuate neuropathic pain by supporting redox homeostasis after sciatic nerve injury in male and female rats. We show that 6 weeks of voluntary wheel running suppresses neuropathic pain development induced by chronic constriction injury across both sexes. This attenuation was associated with reduced nitrotyrosine immunoreactivity-a marker for peroxynitrite-at the sciatic nerve injury site. Our data suggest …

Loss Of Lamp5 Interneurons Drives Neuronal Network Dysfunction In Alzheimer’S Disease, Yuanyuan Deng, Mian Bi, Fabien Delerue, Shelley L Forrest, Gabriella Chan, Julia Van Der Hoven, Annika Van Hummel, Astrid F Feiten, Seojin Lee, Ivan Martinez-Valbuena, Tim Karl, Gabor G Kovacs, Grant Morahan, Yazi D Ke, Lars M Ittner

Faculty, Staff and Student Publications

In Alzheimer's disease (AD), where amyloid-β (Aβ) and tau deposits in the brain, hyperexcitation of neuronal networks is an underlying disease mechanism, but its cause remains unclear. Here, we used the Collaborative Cross (CC) forward genetics mouse platform to identify modifier genes of neuronal hyperexcitation. We found LAMP5 as a novel regulator of hyperexcitation in mice, critical for the survival of distinct interneuron populations. Interestingly, synaptic LAMP5 was lost in AD brains and LAMP5 interneurons degenerated in different AD mouse models. Genetic reduction of LAMP5 augmented functional deficits and neuronal network hypersynchronicity in both Aβ- and tau-driven AD mouse models. …

Transcranial Magnetic Stimulation (Tms) Seeded Tractography Provides Superior Prediction Of Eloquence Compared To Anatomic Seeded Tractography, Matthew Muir, Sarah Prinsloo, Hayley Michener, Arya Shetty, Dhiego Chaves De Almeida Bastos, Jeffrey Traylor, Chibawanye Ene, Sudhakar Tummala, Vinodh A Kumar, Sujit S Prabhu

Faculty, Staff and Student Publications

BACKGROUND: For patients with brain tumors, maximizing the extent of resection while minimizing postoperative neurological morbidity requires accurate preoperative identification of eloquent structures. Recent studies have provided evidence that anatomy may not always predict eloquence. In this study, we directly compare transcranial magnetic stimulation (TMS) data combined with tractography to traditional anatomic grading criteria for predicting permanent deficits in patients with motor eloquent gliomas.

METHODS: We selected a cohort of 42 glioma patients with perirolandic tumors who underwent preoperative TMS mapping with subsequent resection and intraoperative mapping. We collected clinical outcome data from their chart with the primary outcome being …

Cancer-Driving Mutations Are Enriched In Genic Regions Intolerant To Germline Variation, Dimitrios Vitsios, Ryan S Dhindsa, Dorota Matelska, Jonathan Mitchell, Xuequing Zou, Joshua Armenia, Fengyuan Hu, Quanli Wang, Ben Sidders, Andrew R Harper, Slavé Petrovski

Duncan NRI Faculty and Staff Publications

Large reference datasets of protein-coding variation in human populations have allowed us to determine which genes and genic subregions are intolerant to germline genetic variation. There is also a growing number of genes implicated in severe Mendelian diseases that overlap with genes implicated in cancer. We hypothesized that cancer-driving mutations might be enriched in genic subregions that are depleted of germline variation relative to somatic variation. We introduce a new metric, OncMTR (oncology missense tolerance ratio), which uses 125,748 exomes in the Genome Aggregation Database (gnomAD) to identify these genic subregions. We demonstrate that OncMTR can significantly predict driver mutations …

Secure Human Action Recognition By Encrypted Neural Network Inference, Miran Kim, Xiaoqian Jiang, Kristin Lauter, Elkhan Ismayilzada, Shayan Shams

Faculty, Staff and Student Publications

Advanced computer vision technology can provide near real-time home monitoring to support "aging in place" by detecting falls and symptoms related to seizures and stroke. Affordable webcams, together with cloud computing services (to run machine learning algorithms), can potentially bring significant social benefits. However, it has not been deployed in practice because of privacy concerns. In this paper, we propose a strategy that uses homomorphic encryption to resolve this dilemma, which guarantees information confidentiality while retaining action detection. Our protocol for secure inference can distinguish falls from activities of daily living with 86.21% sensitivity and 99.14% specificity, with an average …

Insulin Resistance In Depression: A Large Meta-Analysis Of Metabolic Parameters And Variation, Brisa S Fernandes, Estela Salagre, Nitesh Enduru, Iria Grande, Eduard Vieta, Zhongming Zhao

Faculty, Staff and Student Publications

Increased insulin resistance is recognized in psychiatric disorders, such as schizophrenia and bipolar disorder, but its occurrence in depression is less clear. Our aims were to verify if insulin resistance is altered in depression, to test the metabolic subgroup hypothesis of depression and if there are changes with antidepressants. Inclusion criteria were studies including adult subjects with depression and either a control group or follow-up after treatment with antidepressants, and assessing fasting insulin or glucose levels or the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) index. Seventy studies with 240,704 participants were included. Both insulin levels and the HOMA-IR index …

Effect Of Neoadjuvant Chemotherapy On Intraoperative Core Temperature In Patients With Breast Cancer: A Retrospective Cohort Study, Daniel B Zamler, Takashi Shingu, Laura M Kahn, Kristin Huntoon, Cynthia Kassab, Martina Ott, Katarzyna Tomczak, Jintan Liu, Yating Li, Ivy Lai, Rocio Zorilla-Veloz, Cassian Yee, Kunal Rai, Betty Ys Kim, Stephanie S Watowich, Amy B Heimberger, Giulio F Draetta, Jian Hu

Faculty, Staff and Student Publications

Novel therapeutic strategies targeting glioblastoma (GBM) often fail in the clinic, partly because preclinical models in which hypotheses are being tested do not recapitulate human disease. To address this challenge, we took advantage of our previously developed spontaneous Qk/Trp53/Pten (QPP) triple-knockout model of human GBM, comparing the immune microenvironment of QPP mice with that of patient-derived tumors to determine whether this model provides opportunity for gaining insights into tumor physiopathology and preclinical evaluation of therapeutic agents. Immune profiling analyses and single-cell sequencing of implanted and spontaneous tumors from QPP mice and from patients with glioma revealed intratumoral immune components that …

A Weakened Recurrent Circuit In The Hippocampus Of Rett Syndrome Mice Disrupts Long-Term Memory Representations, Lingjie He, Matthew S Caudill, Junzhan Jing, Wei Wang, Yaling Sun, Jianrong Tang, Xiaolong Jiang, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Successful recall of a contextual memory requires reactivating ensembles of hippocampal cells that were allocated during memory formation. Altering the ratio of excitation-to-inhibition (E/I) during memory retrieval can bias cell participation in an ensemble and hinder memory recall. In the case of Rett syndrome (RTT), a neurological disorder with severe learning and memory deficits, the E/I balance is altered, but the source of this imbalance is unknown. Using in vivo imaging during an associative memory task, we show that during long-term memory retrieval, RTT CA1 cells poorly distinguish mnemonic context and form larger ensembles than wild-type mouse cells. Simultaneous multiple …

Counterfactual Analysis Of Differential Comorbidity Risk Factors In Alzheimer’S Disease And Related Dementias, Yejin Kim, Kai Zhang, Sean I Savitz, Luyao Chen, Paul E Schulz, Xiaoqian Jiang

Faculty, Staff and Student Publications

Alzheimer’s disease and related dementias (ADRD) is a multifactorial disease that involves several different etiologic mechanisms with various comorbidities. There is also significant heterogeneity in the prevalence of ADRD across diverse demographics groups. Association studies on such heterogeneous comorbidity risk factors are limited in their ability to determine causation. We aim to compare counterfactual treatment effects of various comorbidity in ADRD in different racial groups (African Americans and Caucasians). We used 138,026 ADRD and 1:1 matched older adults without ADRD from nationwide electronic health records, which extensively cover a large population’s long medical history in breadth. We matched African Americans …

The Current Status And Shortcomings Of Stereotactic Radiosurgery, Hunter Mehrens, Trang Nguyen, Sharbacha Edward, Shannon Hartzell, Mallory Glenn, Daniela Branco, Nadia Hernandez, Paola Alvarez, Andrea Molineu, Paige Taylor, Stephen Kry

Faculty, Staff and Student Publications

Background: Stereotactic radiosurgery (SRS) is a common treatment for intracranial lesions. This work explores the state of SRS treatment delivery to characterize current treatment accuracy based on treatment parameters.

Methods: NCI clinical trials involving SRS rely on an end-to-end treatment delivery on a patient surrogate (credentialing phantom) from the Imaging and Radiation Oncology Core (IROC) to test their treatment accuracy. The results of 1072 SRS phantom irradiations between 2012 and 2020 were retrospectively analyzed. Univariate analysis and random forest models were used to associate irradiation conditions with phantom performance. The following categories were evaluated in terms of how they predicted …

Pathogenic Tau Accelerates Aging-Associated Activation Of Transposable Elements In The Mouse Central Nervous System, Paulino Ramirez, Gabrielle Zuniga, Wenyan Sun, Adrian Beckmann, Elizabeth Ochoa, Sarah L Devos, Bradley Hyman, Gabriel Chiu, Ethan R Roy, Wei Cao, Miranda Orr, Virginie Buggia-Prevot, William J Ray, Bess Frost

Faculty, Staff and Student Publications

Transposable elements comprise almost half of the mammalian genome. A growing body of evidence suggests that transposable element dysregulation accompanies brain aging and neurodegenerative disorders, and that transposable element activation is neurotoxic. Recent studies have identified links between pathogenic forms of tau, a protein that accumulates in Alzheimer's disease and related "tauopathies," and transposable element-induced neurotoxicity. Starting with transcriptomic analyses, we find that age- and tau-induced transposable element activation occurs in the mouse brain. Among transposable elements that are activated at the RNA level in the context of brain aging and tauopathy, we find that the endogenous retrovirus (ERV) class …

A Comparison Of Machine Learning Classifiers For Pediatric Epilepsy Using Resting-State Functional Mri Latency Data, Ryan D Nguyen, Matthew D Smyth, Liang Zhu, Ludovic P Pao, Shannon K Swisher, Emmett H Kennady, Anish Mitra, Rajan P Patel, Jeremy E Lankford, Gretchen Von Allmen, Michael W Watkins, Michael E Funke, Manish N Shah

Faculty, Staff and Student Publications

Epilepsy affects 1 in 150 children under the age of 10 and is the most common chronic pediatric neurological condition; poor seizure control can irreversibly disrupt normal brain development. The present study compared the ability of different machine learning algorithms trained with resting-state functional MRI (rfMRI) latency data to detect epilepsy. Preoperative rfMRI and anatomical MRI scans were obtained for 63 patients with epilepsy and 259 healthy controls. The normal distribution of latency z-scores from the epilepsy and healthy control cohorts were analyzed for overlap in 36 seed regions. In these seed regions, overlap between the study cohorts ranged from …

Searching For The Majority: Algorithms Of Voluntary Control, Jin Fan, Kevin G. Guise, Xun Liu, Hongbin Wang

Faculty, Staff and Student Publications

Voluntary control of information processing is crucial to allocate resources and prioritize the processes that are most important under a given situation; the algorithms underlying such control, however, are often not clear. We investigated possible algorithms of control for the performance of the majority function, in which participants searched for and identified one of two alternative categories (left or right pointing arrows) as composing the majority in each stimulus set. We manipulated the amount (set size of 1, 3, and 5) and content (ratio of left and right pointing arrows within a set) of the inputs to test competing hypotheses …