Medical Pathology Commons^™

Low-Dose Immune Tolerance Induction In Children With Severe Hemophilia A With High-Titer Inhibitors: Type Of Factor 8 Mutation And Outcomes, Jie Sun, Zekun Li, Gang Li, Kun Huang, Di Ai, Guoqing Liu, Wanru Yao, Xingjuan Xie, Hao Gu, Yingzi Zhen, Zhenping Chen, Runhui Wu

Faculty, Staff and Student Publications

BACKGROUND: No studies evaluated the role of

OBJECTIVES: To explore the association between

METHODS: Children SHA with high-titer inhibitors who received low-dose ITI therapy at least for 1 year were included in this study. Based on the risk of inhibitor development,

RESULTS: Of 104 children included, 101 had

CONCLUSIONS: Types of

Classification Of Breast Cancer Histopathological Images Using Semi-Supervised Gans, Balaji Avvaru, Nibhrat Lohia, Sowmya Mani, Vijayasrikanth Kaniti

SMU Data Science Review

Breast cancer is diagnosed more frequently than skin cancer in women in the United States. Most breast cancer cases are diagnosed in women, while children and men are less likely to develop the disease. Various tissues in the breast grow uncontrollably, resulting in breast cancer. Different treatments analyze microscopic histopathology images for diagnosis that help accurately detect cancer cells. Deep learning is one of the evolving techniques to classify images where accuracy depends on the volume and quality of labeled images. This study used various pre-trained models to train the histopathological images and analyze these models to create a new …

Associations Between Cannabis, Psychosis, And Schizophrenia In Adolescents, Lauren Moment

Academic Leadership Journal in Student Research

The effects of cannabis use on the brain, mind, and body have been studied for decades. The developing brain, particularly the adolescent and young adult brain, undergoes critical development that makes it especially susceptible to the effects of cannabis use. Among the adverse effects of cannabis use in adolescence and young adulthood, psychosis and psychotic disorders (e.g., schizophrenia) have been examined. The association of cannabis use with schizophrenia was first elucidated in a Swedish study of army conscripts. Specifically, conscripts reported their cannabis use exposure and were followed longitudinally to assess the emergence of schizophrenia. The authors found that those …

Unreliable Automated Complete Blood Count Results: Causes, Recognition, And Resolution, Gene Gulati, Guldeep Uppal, Jerald Z. Gong

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Automated hematology analyzers generate accurate complete blood counts (CBC) results on nearly all specimens. However, every laboratory encounters, at times, some specimens that yield no or inaccurate result(s) for one or more CBC parameters even when the analyzer is functioning properly and the manufacturer's instructions are followed to the letter. Inaccurate results, which may adversely affect patient care, are clinically unreliable and require the attention of laboratory professionals. Laboratory professionals must recognize unreliable results, determine the possible cause(s), and be acquainted with the ways to obtain reliable results on such specimens. We present a concise overview of the known causes …

Healthy Exosomes And Their Effects On Diabetic Cardiomyocytes, Miguel A. Garza, Genaro A. Ramírez-Correa, Maria Lourdes Garza-Rodríguez, Andres J. Medina

MEDI 9331 Scholarly Activities Clinical Years

Extracellular Vesicles, and more specifically, exosomes, are essential for effective cell-to-cell communication in a wide variety of tissues. In the last couple of decades, these nanovesicles have been proven to be active participants and regulators in many disease processes; therefore, their therapeutic effects have been widely studied and proven in various cardiovascular diseases both, in vitro and in vivo. Thus, this study aims at assessing the effects of running healthy mice exosomes on cardiomyocyte and cardiac tissue samples obtained from diabetic mice. Here, we successfully extract exosomes from mice plasma and detect their presence through the use of anti-CD9 and …

Steap1-4 (Six-Transmembrane Epithelial Antigen Of The Prostate 1-4) And Their Clinical Implications For Prostate Cancer, Michael Xu, Latese Evans, Candice L Bizzaro, Fabio Quaglia, Cecilia E Verrillo, Li Li, Julia Stieglmaier, M J Schiewer, Lucia R Languino, William Kevin Kelly

Department of Urology Faculty Papers

Six-Transmembrane Epithelial Antigen of the Prostate 1-4 (STEAP1-4) compose a family of metalloproteinases involved in iron and copper homeostasis and other cellular processes. Thus far, five homologs are known: STEAP1, STEAP1B, STEAP2, STEAP3, and STEAP4. In prostate cancer, STEAP1, STEAP2, and STEAP4 are overexpressed, while STEAP3 expression is downregulated. Although the metalloreductase activities of STEAP1-4 are well documented, their other biological functions are not. Furthermore, the properties and expression levels of STEAP heterotrimers, homotrimers, heterodimers, and homodimers are not well understood. Nevertheless, studies over the last few decades have provided sufficient impetus to investigate STEAP1-4 as potential biomarkers and therapeutic …

Patient With Multiple Genetically Distinct Thyroid Nodules Including Papillary Thyroid Carcinoma Harboring Novel Ywhag-Braf Fusion, Ruihe Lin, Zi-Xuan Wang, Elizabeth Cottrill, Nitika Badjatia, Stacey Gargano

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Next-generation sequencing (NGS) analysis of thyroid samples aids in risk stratification of cytologically indeterminate nodules and contributes to our understanding of molecular mechanisms in thyroid neoplasia. Several genes, including BRAF, RAS, and EIF1AX, are known to play a role in thyroid tumorigenesis. Here we report a case of papillary thyroid carcinoma (PTC) in which a single lesion harbored a novel YWHAG-BRAF fusion and EIF1AX mutation and displayed mixed morphological findings. The patient is a 74-year-old female with multiple incidentally discovered thyroid nodules, two of which were sampled by ultrasound-guided fine needle aspiration (FNA). Cytologic diagnosis for both nodules was suspicious …

The Intricate Interplay Between Cancer Stem Cells And Cell-Of-Origin Of Cancer: Implications For Therapeutic Strategies, Luis Alberto Vega, Misu A Sanson, María Belén Cubria, Shrijana Regmi, Brittany J Shah, Samuel A Shelburne, Anthony R Flores

Faculty, Staff and Student Publications

Antimicrobial resistance-encoding mobile genetic elements (MGEs) may contribute to the disease potential of bacterial pathogens. We previously described the association of Group A Streptococcus (GAS) derived from invasive disease with increasingly frequent antimicrobial resistance (AMR). We hypothesized that a 65-kb AMR-encoding MGE (ICESpyM92), highly conserved among closely related emergent invasive emm92 GAS, contributes to GAS disease potential. Here, we provide evidence that a combination of ICESpyM92- and core genome-dependent differential gene expression (DGE) contributes to invasive disease phenotypes of emergent emm92 GAS. Using isogenic ICESpyM92 mutants generated in distinct emm92 genomic backgrounds, we determined the presence of ICESpyM92 enhances GAS …

Glucose Uptake By Glut1 In Photoreceptors Is Essential For Outer Segment Renewal And Rod Photoreceptor Survival, Lauren L. Daniele, John Y.S. Han, Ivy S Samuels, Ravikiran Komirisetty, Nikhil Mehta, Jessica L Mccord, Minzhong Yu, Yekai Wang, Kathleen Boesze-Battaglia, Brent A Bell, Jianhai Du, Neal S Peachey, Nancy J. Philp

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Photoreceptors consume glucose supplied by the choriocapillaris to support phototransduction and outer segment (OS) renewal. Reduced glucose supply underlies photoreceptor cell death in inherited retinal degeneration and age-related retinal disease. We have previously shown that restricting glucose transport into the outer retina by conditional deletion of Slc2a1 encoding GLUT1 resulted in photoreceptor loss and impaired OS renewal. However, retinal neurons, glia, and the retinal pigment epithelium play specialized, synergistic roles in metabolite supply and exchange, and the cell-specific map of glucose uptake and utilization in the retina is incomplete. In these studies, we conditionally deleted Slc2a1 in a pan-retinal or …

Metastatic Primary Brain Rhabdomyosarcoma In A Pediatric Patient: Illustrative Case, Michel Gustavo Mondragón-Soto, Luis Del Valle, José Alfredo González-Soto, Roberto Alfonso De Leo-Vargas

School of Medicine Faculty Publications

BACKGROUND: Primary intracranial rhabdomyosarcoma is an extraordinarily rare malignant tumor, with even fewer presenting with distant metastasis. To date, only five cases, including the one presented here, have been reported to present metastatic activity. OBSERVATIONS: A 12-year-old boy presented with a few days of headache, nausea, vomiting, but no neurological deficit. Brain computed tomography and magnetic resonance imaging demonstrated hydrocephalus and a cystic lesion with left parieto-occipital extension. After resection, pathology reported primary rhabdomyosarcoma, with positive desmin and myogenin on immunohistochemistry. The patient presented with pulmonary metastasis. The patient had an overall survival of 21 months after diagnosis with optimal …

Altered Genome-Wide Hippocampal Gene Expression Profiles Following Early Life Lead Exposure And Their Potential For Reversal By Environmental Enrichment, Garima Singh, V Singh, T Kim, A Ertel, W Fu, J S Schneider

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Early life lead (Pb) exposure is detrimental to neurobehavioral development. The quality of the environment can modify negative influences from Pb exposure, impacting the developmental trajectory following Pb exposure. Little is known about the molecular underpinnings in the brain of the interaction between Pb and the quality of the environment. We examined relationships between early life Pb exposure and living in an enriched versus a non-enriched postnatal environment on genome-wide transcription profiles in hippocampus CA1. RNA-seq identified differences in the transcriptome of enriched vs. non-enriched Pb-exposed animals. Most of the gene expression changes associated with Pb exposure were reversed by …

In Vivo Determination Of The Human Corneal Elastic Modulus Using Vibrational Optical Coherence Tomography, Marcos A. Crespo, Hiram J. Jimenez, Tanmay Deshmukh, Jose S. Pulido, Ahmed Saeed Saad, Frederick H Silver, Dominick A Benedetto, Christopher J Rapuano, Zeba Syed

Wills Eye Hospital Papers

Purpose: To determine the in vivo elastic modulus of the human cornea using vibrational optical coherence tomography (VOCT).

Methods: Vibrational analysis coupled with optical coherence tomography (OCT) was used to obtain the resonant frequency (RF) and elastic modulus of corneal structural components. VOCT corneal thickness values were measured using OCT images and correlated with corneal thickness determined with Pentacam (Oculus, Wetzlar, Germany). Moduli were obtained at two locations: central cornea (CC) and inferior cornea (IC). Measurements were obtained with and without anesthetic eye drops to assess their effect on the modulus measurements.

Results: VOCT thickness values correlated positively (R2 = …

Perioperative Risks Of The Patient With Heart Failure, Gabrielle Metoyer

Nursing Student Class Projects (Formerly MSN)

Perioperative Risks of the Patient with Heart Failure

Gabrielle Metoyer

Department of Nursing, Otterbein University

NURS 6810 – Advanced Pathophysiology

Dr. Deanna Batross and Dr. Shivani Bhatnagar

August 5, 2022

Abstract

According to the CDC (2020), heart failure occurs when the heart cannot pump enough blood and oxygen to support other organs in your body. Heart failure is an epidemic disease affecting 1-2% of the population worldwide (Schwinger, 2020). It is one of the leading causes of morbidity and mortality worldwide with an estimated 6.5 million adults with heart failure in the United States (Lo et al., 2021). Medical advances …

Whole Slide Image Data Utilization Informed By Digital Diagnosis Patterns, Kimberly Ashman, Huimin Zhuge, Erin Shanley, Sharon Fox, Shams Halat, Andrew Sholl, Brian Summa, J. Quincy Brown

School of Medicine Faculty Publications

Context: Despite the benefits of digital pathology, data storage and management of digital whole slide images introduces new logistical and infrastructure challenges to traditionally analog pathology labs. Aims: Our goal was to analyze pathologist slide diagnosis patterns to determine the minimum number of pixels required during the diagnosis. Methods: We developed a method of using pathologist viewing patterns to vary digital image resolution across virtual slides, which we call variable resolution images. An additional pathologist reviewed the variable resolution images to determine if diagnoses could still be rendered. Results: Across all slides, the pathologists rarely zoomed in to the full …

Sinus Pauses And Asystole As A Rare Presentation Of Thyrotoxic Crisis: A Case Report, Christian Akem Dimala, Charnjeet Sandhu, Oreoluwa Oladiran, Agnieszka Mochon, William Finneran Iii

Transformative Medicine

Introduction

Thyroid crisis is a rare and life-threatening endocrine emergency characterized by exaggerated clinical manifestations of hyperthyroidism with cardiovascular manifestations being the most severe. Rhythm disturbances, sinus tachycardia and atrial fibrillation, are the commonest cardiac manifestations of severe thyrotoxicosis; however, asystole remains a very atypical and uncommon presentation. We present a case of thyrotoxicosis due to Grave’s disease complicated by multiple episodes of asystole.

Case Presentation

A 65-year-old female recently diagnosed with Grave’s disease presented to the hospital with recurrent episodes of syncope. Her hospital course was significant for atrial fibrillation with subsequent progression to sinus pauses and asystole spontaneously …

A Mathematical Model Of Glut1 Modulation In Rods And Rpe And Its Differential Impact In Cell Metabolism, Andrea Aparicio, Erika T Camacho, Nancy J. Philp, Stephen A Wirkus

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

We present a mathematical model of key glucose metabolic pathways in two cells of the human retina: the rods and the retinal pigmented epithelium (RPE). Computational simulations of glucose transporter 1 (GLUT1) inhibition in the model accurately reproduce experimental data from conditional knockout mice and reveal that modification of GLUT1 expression levels of both cells differentially impacts their metabolism. We hypothesize that, under glucose scarcity, the RPE’s energy producing pathways are altered in order to preserve its functionality, impacting the photoreceptors’ outer segment renewal. On the other hand, when glucose is limited in the rods, aerobic glycolysis is preserved, which …

Ros And Mirna Dysregulation In Ovarian Cancer Development, Angiogenesis And Therapeutic Resistance, David C Stieg, Yifang Wang, Ling-Zhi Liu, Bing-Hua Jiang

Kimmel Cancer Center Faculty Papers

The diverse repertoires of cellular mechanisms that progress certain cancer types are being uncovered by recent research and leading to more effective treatment options. Ovarian cancer (OC) is among the most difficult cancers to treat. OC has limited treatment options, especially for patients diagnosed with late-stage OC. The dysregulation of miRNAs in OC plays a significant role in tumorigenesis through the alteration of a multitude of molecular processes. The development of OC can also be due to the utilization of endogenously derived reactive oxygen species (ROS) by activating signaling pathways such as PI3K/AKT and MAPK. Both miRNAs and ROS are …

Ets-Related Gene (Erg) Is Differentially Expressed In Dermatofibroma (Fibrous Histiocytoma) As Compared With Dermatofibromasarcoma Protuberans And Hypertrophic Scars: A Pilot Immunohistochemical Study, Meredith Hengy, Jesse Veenstra, Kyle Perry, David M. Ozog, Ben Friedman

Medical Student Research Symposium

Immunohistochemical staining can be of great utility in differentiating various cutaneous spindle cell neoplasms, particularly when the histomorphological appearance of the lesions is inconclusive. Nuclear staining for ETS-related gene (ERG), a highly sensitive endothelial cell marker, has seldom been studied in the context of cutaneous spindle cell neoplasms. Little is known about its specificity for vascular differentiation. In this pilot study, immunohistochemical analysis for ERG was performed on fifteen dermatofibromas (DF), ten keloids, and nine dermatofibrosarcoma protuberans tumors (DFSP). Consistent nuclear expression of ERG was found in DF [100% (15/15) of the lesions demonstrated >50% labeling of tumor cells with …

A Single Dose Of The Deactivated Rabies-Virus Vectored Covid-19 Vaccine, Coravax, Is Highly Efficacious And Alleviates Lung Inflammation In The Hamster Model, Drishya Kurup, Christoph Wirblich, Leila Zabihi Diba, Rachael Lambert, Megan Watson, Noor Shaikh, Holly Ramage, Charalambos Solomides, Matthias J Schnell

Department of Microbiology and Immunology Faculty Papers

Without sufficient herd immunity through either vaccination or natural infection, the coronavirus disease 2019 pandemic is unlikely to be controlled. Waning immunity with the currently approved vaccines suggests the need to evaluate vaccines causing the induction of long-term responses. Here, we report the immunogenicity and efficacy of our adjuvanted single-dose Rabies-vectored SARS-CoV-2 S1 vaccine, CORAVAX, in hamsters. CORAVAX induces high SARS-CoV-2 S1-specific and virus-neutralizing antibodies (VNAs) that prevent weight loss, viral loads, disease, lung inflammation, and the cytokine storm in hamsters. We also observed high Rabies VNA titers. In summary, CORAVAX is a promising dual-antigen vaccine candidate for clinical evaluation …

Bacille Calmette-Guérin Vaccine Reprograms Human Neonatal Lipid Metabolism In Vivo And In Vitro, Joann Diray-Arce, Asimenia Angelidou, Kristoffer Jarlov Jensen, Maria Giulia Conti, Rachel S Kelly, Matthew Pettengill, Mark Liu, Simon D Van Haren, Scott D Mcculloch, Greg Michelloti, Olubukola Idoko, Tobias R Kollmann, Beate Kampmann, Hanno Steen, Al Ozonoff, Jessica Lasky-Su, Christine S Benn, Ofer Levy

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Vaccines have generally been developed with limited insight into their molecular impact. While systems vaccinology enables characterization of mechanisms of action, these tools have yet to be applied to infants, who are at high risk of infection and receive the most vaccines. Bacille Calmette-Guérin (BCG) protects infants against disseminated tuberculosis (TB) and TB-unrelated infections via incompletely understood mechanisms. We employ mass-spectrometry-based metabolomics of blood plasma to profile BCG-induced infant responses in Guinea-Bissau in vivo and the US in vitro. BCG-induced lysophosphatidylcholines (LPCs) correlate with both TLR-agonist- and purified protein derivative (PPD, mycobacterial antigen)-induced blood cytokine production in vitro, raising the …

Impact Of A Novel Interdisciplinary Online Course: Student Perspectives Related To Pandemics And Covid-19, Anna Russ

ONU Student Research Colloquium

Misinformation regarding COVID-19 has clouded the judgment and perspectives of many individuals. At Ohio Northern University, a new interdisciplinary online elective course offers students the opportunity to gain evidence-based insight about the far-reaching implications of pandemics and COVID-19. The purpose of this project is to evaluate the impact that this course has made on student perspectives relating to various topics about pandemics and COVID-19.

This semester-long online elective course was taught in an interdisciplinary fashion by professors from different departments and disciplines within Ohio Northern University. Topics covered included: the history of pandemics; public health and healthcare response; COVID-19 transmission, …

Ocular Adnexal Metastases From Renal Cell Carcinoma: An Update And Comprehensive Literature Review, Tejal Magan, Tejus Pradeep, Madalina Tuluc, Jurij R. Bilyk, Tatyana Milman

Wills Eye Hospital Papers

PURPOSE: The purpose of this study was to review the clinical presentation, systemic work-up, and outcomes of all previously reported ocular adnexal (OA) metastases from renal cell carcinoma (RCC). METHODS: This was a literature review. PubMed and Google Scholar databases were searched for all well-documented cases of OA metastases from RCC. RESULTS: Final analysis identified 44 patients with either biopsy-confirmed (41/44, 93%) or treatment response-documented (3/44, 6%) OA metastases from RCC. Thirty-four (77%) patients were male. The median age was 60 years (mean: 60, range: 22-87 years). The most common presenting signs were proptosis (19/44, 43%) and OA mass (14/44, …

Gm1 Ganglioside Modifies Microglial And Neuroinflammatory Responses To Α-Synuclein In The Rat Aav-A53t Α-Synuclein Model Of Parkinson's Disease, Jay S Schneider, Garima Singh, Courtney K. Williams, Vikrant Singh

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Among the pathological events associated with the dopaminergic neurodegeneration characteristic of Parkinson's disease (PD) are the accumulation of toxic forms of α-synuclein and microglial activation associated with neuroinflammation. Although numerous other processes may participate in the pathogenesis of PD, the two factors mentioned above may play critical roles in the initiation and progression of dopamine neuron degeneration in PD. In this study, we employed a slowly progressing model of PD using adeno-associated virus-mediated expression of human A53T α-synuclein into the substantia nigra on one side of the brain and examined the microglial response in the striatum on the injected side …

Prenatal Drug Exposure And Its Effects On Fetal Development: Clinical And Health Education Implications, Johanna Marie Olo Tapangan

Senior Honors Theses

Prenatal drug exposure is a common clinical phenomenon in pregnancy cases. Pregnancy is a fragile period of time for both the mother and the fetus. Therefore, strict drug regulation is important to ensure the safety and wellbeing of the developing fetus. Certain drugs, once thought to be safe, have been found to have detrimental effects on the normal development of functioning organ systems in the fetus. Current research has identified drugs that when taken during pregnancy can result in the onset of fetal physical abnormalities, impaired brain development, and disrupted organogenesis and organ function. Thalidomide, losartan, opioids, alcohol, and caffeine …

Patterns Of Crystallin Gene Expression In Differentiation State Specific Regions Of The Embryonic Chicken Lens, Zhiwei Ma, Daniel Chauss, Joshua Disatham, Xiaodong Jiao, Lisa Ann Brennan, A Sue Menko, Marc Kantorow, J Fielding Hejtmancik

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Purpose: Transition from lens epithelial cells to lens fiber cell is accompanied by numerous changes in gene expression critical for lens transparency. We identify expression patterns of highly prevalent genes including ubiquitous and enzyme crystallins in the embryonic day 13 chicken lens.

Methods: Embryonic day 13 chicken lenses were dissected into central epithelial cell (EC), equatorial epithelial cell (EQ), cortical fiber cell (FP), and nuclear fiber cell (FC) compartments. Total RNA was prepared, subjected to high-throughput unidirectional mRNA sequencing, analyzed, mapped to the chicken genome, and functionally grouped.

Results: A total of 77,097 gene-specific transcripts covering 17,450 genes were expressed, …

Medical Norm Of Psychiatric Misdiagnoses In Rare Disease Patients, Rachel Han

Publications and Research

Spring 2022 ENG 120 Student Final Research Paper on the medical norm of psychiatric misdiagnosis throughout the diagnostic journeys of rare disease patients. The idea of a norm was taken from Chimamanda Ngozi Adichie's Tedx Talk "The Danger of a Single Story". Paper discusses prevalence, harmful effects, and origin of this medical norm. Includes discussion of statistical data quoted relating to prevalence of rare diseases as well as anecdotal evidence of the severe ramifications of this norm. Discussion of how medically unexplained symptoms such as mysterious chronic pain often lead to the phenomenon of the psychogenic inference. Origins of this …

The Pro-Fibrotic Response Of Mesenchymal Leader Cells To Lens Wounding Involves Hyaluronic Acid, Its Receptor Rhamm, And Vimentin, A. Sue Menko, Alison Romisher, Janice L Walker

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Hyaluronic Acid/Hyaluronan (HA) is a major component of the provisional matrix deposited by cells post-wounding with roles both in regulating cell migration to repair a wound and in promoting a fibrotic outcome to wounding. Both are mediated through its receptors CD44 and RHAMM. We now showed that HA is present in the provisional matrix assembled on the substrate surface in a lens post-cataract surgery explant wound model in which mesenchymal leader cells populate the wound edges to direct migration of the lens epithelium across the adjacent culture substrate onto which this matrix is assembled. Inhibiting HA expression with 4-MU blocked …

68-Year Old Man With Progressive Weakness And Ventilator Dependent Respiratory Failure: A Case Report Of Sporadic Late Onset Nemaline Myopathy, P. Kirupaharan, Daniel Kramer, Alan Gandler, Lawrence C. Kenyon, Ross Summer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Background: Neuromuscular pathologies must be considered when caring for patients with persistent or progressive respiratory failure. Pertinent disease states may involve skeletal muscles of respiration or associated neurologic structures including motor neurons, peripheral neurons and the neuromuscular junction. Diagnosis may require pulmonary function testing, neurophysiologic studies, imaging, and/or muscle biopsy.

Case presentation: A 68-year-old male was transferred to our intensive care unit (ICU) for management of ventilator dependent respiratory failure. Upon further historical review, he described gradually worsening gait instability and muscle weakness, which was previously attributed to vascular Parkinsonism in the setting of known cerebrovascular disease. Upon arrival to …

Uncontrolled Mitochondrial Calcium Uptake Underlies The Pathogenesis Of Neurodegeneration In Micu1-Deficient Mice And Patients, Raghavendra Singh, Adam Bartok, Melanie Paillard, Ashley L. Tyburski, Melanie B Elliott, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Dysregulation of mitochondrial Ca2+ homeostasis has been linked to neurodegenerative diseases. Mitochondrial Ca2+ uptake is mediated via the calcium uniporter complex that is primarily regulated by MICU1, a Ca2+-sensing gatekeeper. Recently, human patients with MICU1 loss-of-function mutations were diagnosed with neuromuscular and cognitive impairments. While studies in patient-derived cells revealed altered mitochondrial calcium signaling, the neuronal pathogenesis was difficult to study. To fill this void, we created a neuron-specific MICU1-KO mouse model. These animals show progressive, abnormal motor and cognitive phenotypes likely caused by the degeneration of motor neurons in the spinal cord and the cortex. We found increased susceptibility …

Fluorescence Imaging Detection Of Nanodomain Redox Signaling Events At Organellar Contacts, David M. Booth, Péter Várnai, Suresh K Joseph, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

This protocol describes how to visualize, detect, and analyze redox signals (oxidative bursts) at the ER-mitochondrial interface. It uses drug-inducible crosslinking to target the genetically encoded glutathione redox sensor Grx1roGFP2 to organellar contact sites to measure local redox changes associated with transient depolarizations of the mitochondrial membrane potential (flickers). The strategy allows imaging of the oxidized to reduced glutathione ratio (GSSG:GSH) in subcellular regions below the diffraction limit with good temporal resolution and minimum phototoxicity. Moreover, the strategy also applies to diverse parameters including pH, H2O2, and Ca2+.