50 results on '"Miranda CJ"'
Search Results
2. Force-Feeding: Traumatic Nasoenteric Tube Placement Complicated by Pneumothorax.
- Author
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Miranda CJ and Shah AR
- Published
- 2025
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3. Dysphagia Megalatriensis: An Uncommon Cardiac Mimicker of Gastroesophageal Dysphagia.
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Palatnic L, Moyer RR, and Miranda CJ
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- 2024
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4. Idelalisib-Induced Pneumonitis in Chronic Lymphocytic Leukemia.
- Author
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Ravi SN, Choi IW, Ngapgue EK, Stroiney AG, and Miranda CJ
- Abstract
Idelalisib, a phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, effectively treats relapsed chronic lymphocytic leukemia (CLL). While this targeted approach offers a therapeutic edge, particularly in B-cell malignancies, it is associated with complications such as pneumonitis. This report details idelalisib-induced pneumonitis, highlighting the importance of early diagnosis and tailored treatment in achieving a favorable patient outcome., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Ravi et al.)
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- 2024
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5. Undifferentiated Carcinoma of the Pancreas With Osteoclast-Like Giant Cells: A Grave Oncologic Diagnosis.
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Miranda CJ, Dove EJ, and Azad F
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- 2024
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6. Delayed Presentation of Malignancy-Associated Pseudoachalasia of the Gastric Cardia.
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Miranda CJ, Azad F, Moyer RR, Ravi SN, and Sparacino GM
- Abstract
Pseudoachalasia is a condition in which symptoms, manometry, and imaging findings highly resemble primary achalasia but has a secondary etiology. The majority of patients with pseudoachalasia have the condition as the result of a malignancy, most often at the gastroesophageal junction. There may be issues with timely identification of this malignancy as symptoms are often obscure with diagnostic testing yielding nonspecific results. We describe a case of a 65-year-old diabetic female smoker with a four-month history of intractable vomiting, abdominal pain, and weight loss who was belatedly found to have an adenocarcinoma at the gastric cardia necessitating a total gastrectomy and chemotherapy administration. The case educates clinicians on the clinical alarm symptoms related to malignant pseudoachalasia and stresses the paramount importance of performing a timely esophagogastroduodenoscopy in all cases of achalasia, even with seemingly normal imaging, to rule out pseudoachalasia related to malignancy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Miranda et al.)
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- 2024
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7. Novel MECP2 gene therapy is effective in a multicenter study using two mouse models of Rett syndrome and is safe in non-human primates.
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Powers S, Likhite S, Gadalla KK, Miranda CJ, Huffenberger AJ, Dennys C, Foust KD, Morales P, Pierson CR, Rinaldi F, Perry S, Bolon B, Wein N, Cobb S, Kaspar BK, and Meyer KC
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- Humans, Mice, Animals, Primates genetics, Genetic Therapy, Mutation, Rett Syndrome genetics, Rett Syndrome therapy, Rett Syndrome metabolism
- Abstract
The AAV9 gene therapy vector presented in this study is safe in mice and non-human primates and highly efficacious without causing overexpression toxicity, a major challenge for clinical translation of Rett syndrome gene therapy vectors to date. Our team designed a new truncated methyl-CpG-binding protein 2 (MECP2) promoter allowing widespread expression of MECP2 in mice and non-human primates after a single injection into the cerebrospinal fluid without causing overexpression symptoms up to 18 months after injection. Additionally, this new vector is highly efficacious at lower doses compared with previous constructs as demonstrated in extensive efficacy studies performed by two independent laboratories in two different Rett syndrome mouse models carrying either a knockout or one of the most frequent human mutations of Mecp2. Overall, data from this multicenter study highlight the efficacy and safety of this gene therapy construct, making it a promising candidate for first-in-human studies to treat Rett syndrome., Competing Interests: Declaration of interests B.K.K. and NCH hold patent filings on this work and received royalties. B.B. received compensation for histopathological analysis., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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8. Preclinical evaluation of FLT190, a liver-directed AAV gene therapy for Fabry disease.
- Author
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Jeyakumar JM, Kia A, Tam LCS, McIntosh J, Spiewak J, Mills K, Heywood W, Chisari E, Castaldo N, Verhoef D, Hosseini P, Kalcheva P, Cocita C, Miranda CJ, Canavese M, Khinder J, Rosales C, Hughes D, Sheridan R, Corbau R, and Nathwani A
- Subjects
- Animals, Humans, Mice, Cells, Cultured, Fibroblasts, Genetic Vectors, Liver metabolism, alpha-Galactosidase genetics, alpha-Galactosidase metabolism, Fabry Disease genetics, Fabry Disease therapy, Genetic Therapy
- Abstract
Fabry disease is an X-linked lysosomal storage disorder caused by loss of alpha-galactosidase A (α-Gal A) activity and is characterized by progressive accumulation of glycosphingolipids in multiple cells and tissues. FLT190, an investigational gene therapy, is currently being evaluated in a Phase 1/2 clinical trial in patients with Fabry disease (NCT04040049). FLT190 consists of a potent, synthetic capsid (AAVS3) containing an expression cassette with a codon-optimized human GLA cDNA under the control of a liver-specific promoter FRE1 (AAV2/S3-FRE1-GLAco). For mouse studies FLT190 genome was pseudotyped with AAV8 for efficient transduction. Preclinical studies in a murine model of Fabry disease (Gla-deficient mice), and non-human primates (NHPs) showed dose-dependent increases in plasma α-Gal A with steady-state observed 2 weeks following a single intravenous dose. In Fabry mice, AAV8-FLT190 treatment resulted in clearance of globotriaosylceramide (Gb3) and globotriaosylsphingosine (lyso-Gb3) in plasma, urine, kidney, and heart; electron microscopy analyses confirmed reductions in storage inclusion bodies in kidney and heart. In NHPs, α-Gal A expression was consistent with the levels of hGLA mRNA in liver, and no FLT190-related toxicities or adverse events were observed. Taken together, these studies demonstrate preclinical proof-of-concept of liver-directed gene therapy with FLT190 for the treatment of Fabry disease., (© 2023. The Author(s).)
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- 2023
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9. Mycophenolate Mofetil-Induced Colonic Injury Manifesting Endoscopically As Ischemic Colitis.
- Author
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Miranda CJ, Ali MH, Ayaz M, Khan RM, and Ismail M
- Abstract
Mycophenolate mofetil (MMOF) is a commonly used immunosuppressive prodrug in kidney transplant patients. However, it is not without side effects. The most common of these is diarrhea which inadvertently leads to colonoscopic and endoscopic evaluation when all other workup returns negative. Colonoscopies often show diffuse ulcers and colitis changes depending on the degree of diarrhea. In rare situations, MMOF-induced ischemic colitis may occur on gross endoscopy. We describe an unusual phenomenon of an adult male status post renal transplant with histopathologically diagnosed MMOF-induced colitis who developed gross endoscopic findings concerning ischemic colitis. Our case highlights the importance of recognizing that MMOF-induced colonic changes can rarely mimic ischemic colitis. With this in mind, we aim for gastroenterologists to better understand the varying endoscopic colonic findings of this immunosuppressive drug., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Miranda et al.)
- Published
- 2023
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10. Diagnostic Obscurity of Gastrointestinal Subepithelial Tumors: An Organizing Gastric Hematoma Requiring En Bloc Resection.
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Miranda CJ, Schertzing W, Shah A, and Del Prado PAR
- Abstract
Gastric subepithelial tumors (SETs) are often incidentally found during examinations of the gastrointestinal tract. Able to arise from any layer of the stomach, these tumors are predominantly asymptomatic and are classified as either benign or malignant based on size, consistency, shape, and mobility as determined by endoscopic evaluation. We present the first reported case of a gastric SET presenting as a chronic organizing hematoma. In doing so, we discuss the necessity of multimodal imaging techniques and multidisciplinary management in identifying often obscure gastric SETs to intervene on potentially malignant masses early., (© 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)
- Published
- 2023
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11. Impact of Adding a Rapid PCR-Based Blood Culture Identification Panel to the Antimicrobial Stewardship Program of Patients with Febrile Neutropenia in a Peruvian Referral Hospital.
- Author
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Pérez-Lazo G, Del Valle-Mendoza J, Sandoval-Ahumada R, Soto-Febres F, Castillo-Córdova R, Zárate-Tantaleán M, Morales-Castillo L, Páucar-Miranda CJ, Altamirano-Molina M, Pacheco-Modesto I, Ruiz de Somocurcio-Cruzado C, Arana-Jurado D, Del Villar-Alarcón C, Vargas-Castro O, Díaz-Bardales C, Guerrero-Arismendiz B, Eyzaguirre-Zapata R, Aguilar-Luis MA, Martins-Luna J, and Silva-Caso W
- Abstract
The addition of Biofire
® FilmArray® Blood Culture Identification panel 2 (BCID2) to the antimicrobial stewardship program (ASP) could improve outcomes in bloodstream infections (BSI) of patients with febrile neutropenia (FN). A pre- and post-quasi-experimental single-center study was conducted at a reference hospital in Peru. Three groups were considered: patients with BSI before ASP intervention (control group), patients with BSI after ASP intervention (group 1), and patients with BSI after ASP intervention plus BCID2 PCR Panel implementation (group 2). Overall, 93 patients were identified (32 control, 30 group 1, 31 group 2). The median time to effective therapy was significantly shorter in group 2 compared to group 1 and control group, respectively (3.75 vs. 10 h, p = 0.004; 3.75 vs. 19 h, p < 0.001). No significant differences in terms of relapse of bacteremia, in-hospital mortality (all cause), and 30-day-all-cause hospital readmission between the three study periods were found. The appropriateness of empirical antimicrobial use, adding or change, and the following de-escalation or discontinuation was significant when the two intervention periods were compared with the control group ( p < 0.001). In addition to the lack of local studies documenting the microbiological profile of FN episodes, adding syndromic panels-based testing could allow for the consolidation of ASP strategies.- Published
- 2023
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12. Eculizumab in the Treatment of Gemcitabine-Induced Atypical Hemolytic Uremic Syndrome.
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Azad F, Miranda CJ, Amin A, Hadwani R, and Gravina M
- Abstract
Gemcitabine-induced hemolytic uremic syndrome is an often-missed condition. We present a case outlining the successful management of a patient with metastatic cholangiocarcinoma treated with gemcitabine who subsequently developed hemolytic uremic syndrome. Early recognition and stopping gemcitabine are essential in this patient population. Complement inhibitors have been used, and our patient improved on eculizumab therapy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Azad et al.)
- Published
- 2023
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13. Diffuse Large B-Cell Lymphoma of the Cecum.
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Azad F, Miranda CJ, Ali M, and Ayaz M
- Abstract
Lymphoma when arising from sites other than lymph nodes is termed extranodal lymphoma, commonly affecting the gastrointestinal tract. Primary colorectal lymphoma is a rare phenomenon among malignancies affecting the colon. We report a case of a patient with a history of Burkitt lymphoma in remission, presenting with a large cecal mass and a new diagnosis of diffuse large B-cell lymphoma treated with chemotherapy., (© 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)
- Published
- 2023
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14. Early orbital involvement in a rare diagnosis of Burkitt-like lymphoma with 11q aberration.
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Azad F, Miranda CJ, Zhang J, and Gravina M
- Abstract
Burkitt-like lymphoma with 11q aberration is a rare condition that poses a diagnostic challenge due to similarities with Burkitt's lymphoma. Due to the rarity of cases, no specific guidelines exist for therapy, and it is treated the same way as Burkitt's lymphoma. We present such a case with initial orbital involvement, an unusual manifestation. Our patient achieved remission with induction chemotherapy, although he will need regular follow-up given the paucity of information on long-term monitoring in these patients., Competing Interests: The authors report no funding or conflicts of interest. The patient provided written informed consent for publication of his case., (Copyright © 2023 Baylor University Medical Center.)
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- 2023
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15. Carfilzomib-Induced Tumor Lysis Syndrome and Biventricular Heart Failure in a Patient With Multiple Myeloma.
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Azad F, Moyer R, Miranda CJ, and Gravina M
- Abstract
Carfilzomib is a proteasome inhibitor (PI) used in multiple myeloma (MM) that is resistant to other therapies. Despite its efficacy and potency, carfilzomib has been associated with kidney injuries, cardiovascular toxic effects, and hematological adverse events. Tumor lysis syndrome (TLS) following the use of PIs in MM, a malignancy not known to cause TLS, has seldom been reported. We present a case of a patient with a known diagnosis of MM who received prior therapy including bortezomib, a first-generation PI, developing worsening heart failure and new onset TLS days after the administration of carfilzomib., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Azad et al.)
- Published
- 2023
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16. Venetoclax and Azacitidine in the Treatment of Blastic Plasmacytoid Dendritic Cell Neoplasm Refractory to Conventional Therapy.
- Author
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Azad F, Zhang J, Miranda CJ, and Gravina M
- Abstract
Blastic plasmacytoid dendritic cell neoplasm is a rare and aggressive hematological malignancy associated with poor prognosis and limited treatment options. No guideline-directed therapy existed until the approval of tagraxofusp in 2018 by the Food and Drug Administration. Multiple clinical trials are undergoing as treatment options continue to evolve. We report a case refractory to tagraxofusp and pivekimab sunirine with subsequent remission achieved on venetoclax and azacitidine therapy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Azad et al.)
- Published
- 2022
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17. An Obscure Presence of Gastroduodenal Involvement in a Newly Diagnosed Ileocolonic Crohn's Disease Patient.
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Miranda CJ, Ali MH, Ayaz M, Soofi Y, and Mahl TC
- Abstract
Whereas typical Crohn's disease is confined to the terminal ileum and presents with abdominal pain and diarrhea, gastroduodenal manifestations of Crohn's disease are rare, with often asymptomatic patient presentations and inconclusive diagnostic testing. It is, however, a more severe form of Crohn's disease and thus warrants treatment with steroids and biologics much earlier than its ileocolonic counterpart. We present the case of a young, otherwise healthy, male with newly diagnosed ileocolonic Crohn's disease with concurrent gastroduodenal involvement that initially failed management with biologic agents. We discuss the clinical manifestations and often obscure pathology of gastroduodenal Crohn's disease and highlight the necessity of performing a concurrent esophagogastroduodenoscopic evaluation on newly diagnosed ileocolonic Crohn's disease to assess the presence of upper gastrointestinal involvement., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Clive Jude Miranda et al.)
- Published
- 2022
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18. Ponatinib-Induced Cerebrovascular Accident (CVA).
- Author
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Azad F, Zhang J, Miranda CJ, and Gravina M
- Abstract
Ponatinib is a highly potent tyrosine kinase inhibitor shown to have excellent outcomes in the treatment of acute and chronic leukemias. Despite its high efficacy, ponatinib has been shown to carry an increased risk for cardiovascular adverse events, not attributable to a known mechanism. We present a case of a patient with Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) who developed a cerebrovascular condition while receiving maintenance therapy with the lowest treatment dose of ponatinib for a prolonged duration., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Azad et al.)
- Published
- 2022
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19. Pulmonary Arteriovenous Malformation in a Rare Case of Hereditary Hemorrhagic Telangiectasia.
- Author
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Azad F, Miranda CJ, and Sparacino GM
- Abstract
Hereditary hemorrhagic telangiectasia is a rare condition presenting with anemia requiring transfusion and nosebleeds often refractory to supportive therapy. We discuss a case of a male in his 60s with a history of epistaxis, anemia requiring transfusions, and acute on chronic worsening shortness of breath presenting for evaluation. He was diagnosed with hereditary hemorrhagic telangiectasia. In addition, he was found to have pulmonary arteriovenous malformations and nonbleeding gastric telangiectasias. The patient underwent coil embolization of pulmonary arteriovenous malformations with a resolution of his shortness of breath and his anemia improved with iron supplementation., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Azad et al.)
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- 2022
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20. Severe Cholestatic Drug-Induced Liver Injury With Cephalosporin Use.
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Yang K, Moga T, Nallapeta NS, Duve R, Miranda CJ, Ismail M, and Mahl T
- Abstract
Drug-induced liver injury (DILI) is a phenomenon that occurs with nearly all classes of medications. Cholestatic DILI represents a fraction of these cases and can present as bland cholestasis, cholestatic hepatitis, secondary sclerosis cholangitis, and vanishing bile duct syndrome. Risk factors have been identified for cholestatic DILI, including older age, genetic determinants, and certain medications such as amoxicillin-clavulanate. Here, we describe a complicated case of severe cholestatic DILI secondary to cephalosporin use. A 27-year-old female presented to the hospital initially with fever and abdominal pain for four weeks after an emergency C-section for pre-eclampsia and hemolysis, elevated liver enzymes, lowered platelets (HELLP) syndrome. She was found to have a retroperitoneal abscess and underwent bilateral drain placement. She was initially started on cefazolin, and then coverage was broadened to cefepime. Shortly after, alkaline phosphatase (ALP) rose and peaked at 3498 IU/L, with aspartate aminotransferase (AST) and alanine transaminase (ALT) elevated at 274 IU/L and 122 IU/L, respectively. Extensive testing for secondary causes and a liver biopsy were consistent with DILI. Liver enzymes down-trended with the cessation of cefepime. This case report highlights that prompt recognition of the culprit medication is paramount to recovering normal liver function., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Yang et al.)
- Published
- 2022
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21. Ovarian Herniation Through the Mesoappendix : An Unexpected Anatomical Finding During a Routine Laparoscopic Appendectomy.
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Jones CE, Miranda CJ, Poorak MD, and Lawson AG
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- Adult, Appendix surgery, Female, Herniorrhaphy, Humans, Laparoscopy, Ovarian Diseases surgery, Appendectomy methods, Appendicitis surgery, Appendix pathology, Hernia pathology, Incidental Findings, Ovarian Diseases pathology
- Published
- 2021
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22. Sox11 is an Activity-Regulated Gene with Dentate-Gyrus-Specific Expression Upon General Neural Activation.
- Author
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von Wittgenstein J, Zheng F, Wittmann MT, Balta EA, Ferrazzi F, Schäffner I, Häberle BM, Valero-Aracama MJ, Koehl M, Miranda CJ, Kaspar BK, Ekici AB, Reis A, Abrous DN, Alzheimer C, and Lie DC
- Subjects
- Animals, Electroshock, Mice, Mice, Knockout, Patch-Clamp Techniques, Proto-Oncogene Proteins c-fos metabolism, SOXC Transcription Factors metabolism, Dentate Gyrus metabolism, Exploratory Behavior physiology, Gene Expression Regulation, Neuronal Plasticity genetics, Neurons metabolism, SOXC Transcription Factors genetics
- Abstract
Neuronal activity initiates transcriptional programs that shape long-term changes in plasticity. Although neuron subtypes differ in their plasticity response, most activity-dependent transcription factors (TFs) are broadly expressed across neuron subtypes and brain regions. Thus, how region- and neuronal subtype-specific plasticity are established on the transcriptional level remains poorly understood. We report that in young adult (i.e., 6-8 weeks old) mice, the developmental TF SOX11 is induced in neurons within 6 h either by electroconvulsive stimulation or by exploration of a novel environment. Strikingly, SOX11 induction was restricted to the dentate gyrus (DG) of the hippocampus. In the novel environment paradigm, SOX11 was observed in a subset of c-FOS expressing neurons (ca. 15%); whereas around 75% of SOX11+ DG granule neurons were c-FOS+, indicating that SOX11 was induced in an activity-dependent fashion in a subset of neurons. Environmental enrichment or virus-mediated overexpression of SOX11 enhanced the excitability of DG granule cells and downregulated the expression of different potassium channel subunits, whereas conditional Sox11/4 knock-out mice presented the opposite phenotype. We propose that Sox11 is regulated in an activity-dependent fashion, which is specific to the DG, and speculate that activity-dependent Sox11 expression may participate in the modulation of DG neuron plasticity., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2020
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23. An arrestin-1 surface opposite of its interface with photoactivated rhodopsin engages with enolase-1.
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Miranda CJ, Fernandez N, Kamel N, Turner D, Benzenhafer D, Bolch SN, Andring JT, McKenna R, and Smith WC
- Subjects
- Arrestin genetics, Binding Sites, Biomarkers, Tumor genetics, Catalysis, DNA-Binding Proteins genetics, Humans, Multienzyme Complexes genetics, Phosphopyruvate Hydratase genetics, Rhodopsin genetics, Tumor Suppressor Proteins genetics, Arrestin chemistry, Biomarkers, Tumor chemistry, DNA-Binding Proteins chemistry, Models, Molecular, Multienzyme Complexes chemistry, Phosphopyruvate Hydratase chemistry, Rhodopsin chemistry, Tumor Suppressor Proteins chemistry
- Abstract
Arrestin-1 is the arrestin family member responsible for inactivation of the G protein-coupled receptor rhodopsin in photoreceptors. Arrestin-1 is also well-known to interact with additional protein partners and to affect other signaling cascades beyond phototransduction. In this study, we investigated one of these alternative arrestin-1 binding partners, the glycolysis enzyme enolase-1, to map the molecular contact sites between these two proteins and investigate how the binding of arrestin-1 affects the catalytic activity of enolase-1. Using fluorescence quench protection of strategically placed fluorophores on the arrestin-1 surface, we observed that arrestin-1 primarily engages enolase-1 along a surface that is opposite of the side of arrestin-1 that binds photoactivated rhodopsin. Using this information, we developed a molecular model of the arrestin-1-enolase-1 complex, which was validated by targeted substitutions of charge-pair interactions. Finally, we identified the likely source of arrestin's modulation of enolase-1 catalysis, showing that selective substitution of two amino acids in arrestin-1 can completely remove its effect on enolase-1 activity while still remaining bound to enolase-1. These findings open up opportunities for examining the functional effects of arrestin-1 on enolase-1 activity in photoreceptors and their surrounding cells., (© 2020 Miranda et al.)
- Published
- 2020
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24. Inhibition of transient potential receptor vanilloid type 1 suppresses seizure susceptibility in the genetically epilepsy-prone rat.
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Cho SJ, Vaca MA, Miranda CJ, and N'Gouemo P
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- Acoustic Stimulation adverse effects, Analysis of Variance, Animals, Anticonvulsants therapeutic use, Benzoates therapeutic use, Body Temperature, Disease Models, Animal, Dose-Response Relationship, Drug, Epilepsy drug therapy, Epilepsy etiology, Epilepsy genetics, Female, Kindling, Neurologic genetics, Kindling, Neurologic physiology, Male, Oxazoles therapeutic use, Rats, Rats, Mutant Strains, Sex Factors, Time Factors, Epilepsy metabolism, TRPV Cation Channels metabolism
- Abstract
Aims: Intracellular calcium plays an important role in neuronal hyperexcitability that leads to seizures. One calcium influx route of interest is the transient receptor potential vanilloid type 1 (TRPV1) channel. Here, we evaluated the effects of capsazepine (CPZ), a potent blocker of TRPV1 channels on acoustically evoked seizures (audiogenic seizures, AGS) in the genetically epilepsy-prone rat (GEPR-3), a model of inherited epilepsy., Methods: Male and female GEPR-3s were used. For the acute CPZ treatment study, GEPR-3s were tested for AGS susceptibility before and after treatment with various doses of CPZ (0, 1, 3, and 10 mg/kg; ip). For semichronic CPZ treatment study, GEPR-3s were tested for AGS susceptibility before and after 5-day CPZ treatment at the dose of 1 mg/kg (ip). The prevalence, latency, and severity of AGS were recorded and analyzed., Results: We found that acute CPZ pretreatment reduced the seizure severity in male GEPR-3s; the effect was dose-dependent. In female GEPR-3s, however, CPZ treatment completely suppressed the seizure susceptibility. Furthermore, semichronic CPZ treatment suppressed seizure susceptibility in female GEPR-3s, but only reduced the seizure severity in male GEPR-3s., Conclusions: These findings suggest that the TRPV1 channel is a promising molecular target for seizure suppression, with female GEPR-3s exhibiting higher sensitivity than male GEPR-3s., (© 2017 John Wiley & Sons Ltd.)
- Published
- 2018
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25. HSPB1 mutations causing hereditary neuropathy in humans disrupt non-cell autonomous protection of motor neurons.
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Heilman PL, Song S, Miranda CJ, Meyer K, Srivastava AK, Knapp A, Wier CG, Kaspar BK, and Kolb SJ
- Subjects
- Animals, Astrocytes pathology, Cell Survival physiology, Charcot-Marie-Tooth Disease pathology, Coculture Techniques, Humans, Mice, Mice, Transgenic, Molecular Chaperones, Motor Neurons pathology, Neuroglia pathology, Astrocytes physiology, Charcot-Marie-Tooth Disease genetics, Heat-Shock Proteins genetics, Motor Neurons physiology, Mutation genetics, Neoplasm Proteins genetics, Neuroglia physiology
- Abstract
Heat shock protein beta-1 (HSPB1), is a ubiquitously expressed, multifunctional protein chaperone. Mutations in HSPB1 result in the development of a late-onset, distal hereditary motor neuropathy type II (dHMN) and axonal Charcot-Marie Tooth disease with sensory involvement (CMT2F). The functional consequences of HSPB1 mutations associated with hereditary neuropathy are unknown. HSPB1 also displays neuroprotective properties in many neuronal disease models, including the motor neuron disease amyotrophic lateral sclerosis (ALS). HSPB1 is upregulated in SOD1-ALS animal models during disease progression, predominately in glial cells. Glial cells are known to contribute to motor neuron loss in ALS through a non-cell autonomous mechanism. In this study, we examined the non-cell autonomous role of wild type and mutant HSPB1 in an astrocyte-motor neuron co-culture model system of ALS. Astrocyte-specific overexpression of wild type HSPB1 was sufficient to attenuate SOD1(G93A) astrocyte-mediated toxicity in motor neurons, whereas, overexpression of mutHSPB1 failed to ameliorate motor neuron toxicity. Expression of a phosphomimetic HSPB1 mutant in SOD1(G93A) astrocytes also reduced toxicity to motor neurons, suggesting that phosphorylation may contribute to HSPB1 mediated-neuroprotection. These data provide evidence that astrocytic HSPB1 expression may play a central role in motor neuron health and maintenance., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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26. Multicenter study in Colombia: Impact of a multidimensional International Nosocomial Infection Control Consortium (INICC) approach on central line-associated bloodstream infection rates.
- Author
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Álvarez-Moreno CA, Valderrama-Beltrán SL, Rosenthal VD, Mojica-Carreño BE, Valderrama-Márquez IA, Matta-Cortés L, Gualtero-Trujillo SM, Rodríguez-Peña J, Linares-Miranda CJ, Gonzalez-Rubio ÁP, Vega-Galvis MC, Riaño-Forero I, Ariza-Ayala BE, García-Laverde G, Susmann O, Mancera-Páez O, Olarte N, Rendón-Campo LF, Astudillo Y, Trullo-Escobar MD, and Orellano PW
- Subjects
- Adult, Aged, Catheter-Related Infections prevention & control, Colombia epidemiology, Controlled Before-After Studies, Cross Infection prevention & control, Female, Health Services Research, Humans, Male, Middle Aged, Prospective Studies, Sepsis prevention & control, Young Adult, Catheter-Related Infections epidemiology, Catheterization, Central Venous adverse effects, Cross Infection epidemiology, Epidemiological Monitoring, Infection Control methods, Sepsis epidemiology
- Abstract
Background: The objective of this study was to analyze the impact of a multidimensional infection control approach and the use of the International Nosocomial Infection Control Consortium (INICC) Surveillance Online System on central line-associated bloodstream infection (CLABSI) rates from June 2003-April 2010., Methods: We conducted a prospective, before-after surveillance study of 2,564 patients hospitalized in 4 adult intensive care units (ICUs) and 424 patients in 2 pediatric ICUs of 4 hospitals in 2 cities of Colombia. During baseline, we performed outcome surveillance of CLABSI applying the Centers for Disease Control and Prevention's National Healthcare Safety Network definitions. During intervention, we implemented the INICC multidimensional approach and the ISOS, which included a bundle of infection prevention practice interventions, education, outcome surveillance, process surveillance, feedback on CLABSI rates and consequences, and performance feedback of process surveillance. Bivariate and multivariate regression analyses were performed using a logistic regression model to estimate the effect of the intervention on the CLABSI rate., Results: The baseline rate of 12.9 CLABSIs per 1,000 central line (CL) days, with 3,032 CL days and 39 CLABSIs, was reduced to 3.5 CLABSIs per 1,000 CL days, with 3,686 CL days and 13 CLABSIs, accounting for a 73% CLABSI rate reduction (relative risk, 0.27; 95% confidence interval, 0.14-0.52; P=.002)., Conclusions: Implementing the INICC multidimensional infection control approach for CLABSI prevention was associated with a significant reduction in the CLABSI rate of ICUs of Colombia., (Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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27. Oligodendrocytes contribute to motor neuron death in ALS via SOD1-dependent mechanism.
- Author
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Ferraiuolo L, Meyer K, Sherwood TW, Vick J, Likhite S, Frakes A, Miranda CJ, Braun L, Heath PR, Pineda R, Beattie CE, Shaw PJ, Askwith CC, McTigue D, and Kaspar BK
- Subjects
- Amyotrophic Lateral Sclerosis metabolism, Amyotrophic Lateral Sclerosis pathology, Animals, Apoptosis, Biomarkers, C9orf72 Protein genetics, C9orf72 Protein metabolism, Cell Communication, Cell Death, Cell Differentiation, Cell Survival, Disease Models, Animal, Gene Expression Profiling, Humans, Lactic Acid metabolism, Mice, Mice, Transgenic, Mutation, Neural Stem Cells cytology, Neural Stem Cells metabolism, Oligodendroglia cytology, Superoxide Dismutase-1 metabolism, Amyotrophic Lateral Sclerosis genetics, Motor Neurons metabolism, Oligodendroglia metabolism, Superoxide Dismutase-1 genetics
- Abstract
Oligodendrocytes have recently been implicated in the pathophysiology of amyotrophic lateral sclerosis (ALS). Here we show that, in vitro, mutant superoxide dismutase 1 (SOD1) mouse oligodendrocytes induce WT motor neuron (MN) hyperexcitability and death. Moreover, we efficiently derived human oligodendrocytes from a large number of controls and patients with sporadic and familial ALS, using two different reprogramming methods. All ALS oligodendrocyte lines induced MN death through conditioned medium (CM) and in coculture. CM-mediated MN death was associated with decreased lactate production and release, whereas toxicity in coculture was lactate-independent, demonstrating that MN survival is mediated not only by soluble factors. Remarkably, human SOD1 shRNA treatment resulted in MN rescue in both mouse and human cultures when knockdown was achieved in progenitor cells, whereas it was ineffective in differentiated oligodendrocytes. In fact, early SOD1 knockdown rescued lactate impairment and cell toxicity in all lines tested, with the exclusion of samples carrying chromosome 9 ORF 72 (C9orf72) repeat expansions. These did not respond to SOD1 knockdown nor did they show lactate release impairment. Our data indicate that SOD1 is directly or indirectly involved in ALS oligodendrocyte pathology and suggest that in this cell type, some damage might be irreversible. In addition, we demonstrate that patients with C9ORF72 represent an independent patient group that might not respond to the same treatment., Competing Interests: The authors declare no conflict of interest.
- Published
- 2016
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28. Major histocompatibility complex class I molecules protect motor neurons from astrocyte-induced toxicity in amyotrophic lateral sclerosis.
- Author
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Song S, Miranda CJ, Braun L, Meyer K, Frakes AE, Ferraiuolo L, Likhite S, Bevan AK, Foust KD, McConnell MJ, Walker CM, and Kaspar BK
- Subjects
- Aged, Aged, 80 and over, Amyotrophic Lateral Sclerosis pathology, Animals, Astrocytes metabolism, Astrocytes pathology, Cadaver, Cell Death genetics, Disease Models, Animal, Female, Gene Expression Regulation, Histocompatibility Antigens Class I genetics, Humans, Male, Mice, Mice, Transgenic, Middle Aged, Mutation, Superoxide Dismutase genetics, Amyotrophic Lateral Sclerosis genetics, Histocompatibility Antigens Class I biosynthesis, Motor Neurons pathology, Receptors, KIR3DL2 genetics
- Abstract
Astrocytes isolated from individuals with amyotrophic lateral sclerosis (ALS) are toxic to motor neurons (MNs) and play a non-cell autonomous role in disease pathogenesis. The mechanisms underlying the susceptibility of MNs to cell death remain unclear. Here we report that astrocytes derived from either mice bearing mutations in genes associated with ALS or human subjects with ALS reduce the expression of major histocompatibility complex class I (MHCI) molecules on MNs; reduced MHCI expression makes these MNs susceptible to astrocyte-induced cell death. Increasing MHCI expression on MNs increases survival and motor performance in a mouse model of ALS and protects MNs against astrocyte toxicity. Overexpression of a single MHCI molecule, HLA-F, protects human MNs from ALS astrocyte-mediated toxicity, whereas knockdown of its receptor, the killer cell immunoglobulin-like receptor KIR3DL2, on human astrocytes results in enhanced MN death. Thus, our data indicate that, in ALS, loss of MHCI expression on MNs renders them more vulnerable to astrocyte-mediated toxicity.
- Published
- 2016
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29. Twenty-four hour infusion of human recombinant activated protein C (Xigris) early in severe acute pancreatitis: The XIG-AP 1 trial.
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Miranda CJ, Mason JM, Babu BI, Sheen AJ, Eddleston JM, Parker MJ, Pemberton P, and Siriwardena AK
- Subjects
- Acute Disease, Adult, Aged, Anti-Infective Agents administration & dosage, Biomarkers, Drug Administration Schedule, Female, Humans, Inflammation blood, Male, Middle Aged, Protein C administration & dosage, Recombinant Proteins administration & dosage, Recombinant Proteins therapeutic use, Anti-Infective Agents therapeutic use, Pancreatitis drug therapy, Protein C therapeutic use
- Abstract
Objective: Patients with severe acute pancreatitis were excluded from major trials of human recombinant activated protein C (Xigris) because of concern about pancreatic haemorrhage although these individuals have an intense systemic inflammatory response that may benefit from treatment. The object of this study was to provide initial safety data evaluating Xigris in severe acute pancreatitis., Design: Prospective clinical trial recruiting between November 2009 and October 2011. Patients received human recombinant activated protein C (Xigris) for 24 h by intravenous infusion (24 μg/kg/h) in addition to standard clinical care. A matched historical control group treated within the same hospital unit were used to compare outcomes. Of 166 consecutive admitted patients, 43 met the screening criteria for severe acute pancreatitis and 19 were recruited, all contributing to the analyses., Results: Compared to historical controls, there were fewer bleeding events in the Xigris group although the finding did not reach significance (Xigris 0% vs. Control 21%, p = 0.13), similarly further intervention appeared less frequent (11% vs. 47%, p = 0.07) in the treatment group. Length of stay was shorter for patients receiving Xigris (19 vs. 41 days, p = 0.03) as was inotrope use (5% vs. 32%, p = 0.02); mortality and incidence of infections in both groups were similar. Biomarker protein C increased while IL-6 decreased following infusion., Conclusions: A 24-hr infusion of Xigris appears safe when used in patients with severe acute pancreatitis., Trial Registration: Eudract Number 2007-003635-23., (Copyright © 2015 IAP and EPC. Published by Elsevier India Pvt Ltd. All rights reserved.)
- Published
- 2015
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30. Pulmonary inflammation is regulated by the levels of the vesicular acetylcholine transporter.
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Pinheiro NM, Miranda CJ, Perini A, Câmara NO, Costa SK, Alonso-Vale MI, Caperuto LC, Tibério IF, Prado MA, Martins MA, Prado VF, and Prado CM
- Subjects
- Acetylcholine genetics, Acetylcholine metabolism, Animals, Blotting, Western, Cells, Cultured, Cytokines genetics, Cytokines metabolism, Edema etiology, Immunoenzyme Techniques, Lung metabolism, Male, Mice, Mice, Knockout, NF-kappa B genetics, NF-kappa B metabolism, Pneumonia etiology, RNA, Messenger genetics, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, Edema physiopathology, Lung pathology, Pneumonia physiopathology, Vesicular Acetylcholine Transport Proteins physiology
- Abstract
Acetylcholine (ACh) plays a crucial role in physiological responses of both the central and the peripheral nervous system. Moreover, ACh was described as an anti-inflammatory mediator involved in the suppression of exacerbated innate response and cytokine release in various organs. However, the specific contributions of endogenous release ACh for inflammatory responses in the lung are not well understood. To address this question we have used mice with reduced levels of the vesicular acetylcholine transporter (VAChT), a protein required for ACh storage in secretory vesicles. VAChT deficiency induced airway inflammation with enhanced TNF-α and IL-4 content, but not IL-6, IL-13 and IL-10 quantified by ELISA. Mice with decreased levels of VAChT presented increased collagen and elastic fibers deposition in airway walls which was consistent with an increase in inflammatory cells positive to MMP-9 and TIMP-1 in the lung. In vivo lung function evaluation showed airway hyperresponsiveness to methacholine in mutant mice. The expression of nuclear factor-kappa B (p65-NF-kB) in lung of VAChT-deficient mice were higher than in wild-type mice, whereas a decreased expression of janus-kinase 2 (JAK2) was observed in the lung of mutant animals. Our findings show the first evidence that cholinergic deficiency impaired lung function and produce local inflammation. Our data supports the notion that cholinergic system modulates airway inflammation by modulation of JAK2 and NF-kB pathway. We proposed that intact cholinergic pathway is necessary to maintain the lung homeostasis.
- Published
- 2015
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31. Chronic oligodendrogenesis and remyelination after spinal cord injury in mice and rats.
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Hesp ZC, Goldstein EZ, Miranda CJ, Kaspar BK, and McTigue DM
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- Animals, Demyelinating Diseases pathology, Female, Male, Mice, Oligodendroglia cytology, Rats, Rats, Sprague-Dawley, Spinal Cord Injuries pathology, Cell Differentiation physiology, Demyelinating Diseases physiopathology, Nerve Regeneration physiology, Oligodendroglia physiology, Recovery of Function physiology, Spinal Cord Injuries physiopathology
- Abstract
Adult progenitor cells proliferate in the acutely injured spinal cord and their progeny differentiate into new oligodendrocytes (OLs) that remyelinate spared axons. Whether this endogenous repair continues beyond the first week postinjury (wpi), however, is unknown. Identifying the duration of this response is essential for guiding therapies targeting improved recovery from spinal cord injury (SCI) by enhancing OL survival and/or remyelination. Here, we used two PDGFRα-reporter mouse lines and rats injected with a GFP-retrovirus to assess progenitor fate through 80 d after injury. Surprisingly, new OLs were generated as late as 3 months after injury and their processes ensheathed axons near and distal to the lesion, colocalized with MBP, and abutted Caspr+ profiles, suggesting newly formed myelin. Semithin sections confirmed stereotypical thin OL remyelination and few bare axons at 10 wpi, indicating that demyelination is relatively rare. Astrocytes in chronic tissue expressed the pro-OL differentiation and survival factors CNTF and FGF-2. In addition, pSTAT3+ NG2 cells were present through at least 5 wpi, revealing active signaling of the Jak/STAT pathway in these cells. The progenitor cell fate genes Sox11, Hes5, Id2, Id4, BMP2, and BMP4 were dynamically regulated for at least 4 wpi. Collectively, these data verify that the chronically injured spinal cord is highly dynamic. Endogenous repair, including oligodendrogenesis and remyelination, continues for several months after SCI, potentially in response to growth factors and/or transcription factor changes. Identifying and understanding spontaneous repair processes such as these is important so that beneficial plasticity is not inadvertently interrupted and effort is not exerted to needlessly duplicate ongoing spontaneous repair., (Copyright © 2015 the authors 0270-6474/15/351274-17$15.00/0.)
- Published
- 2015
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32. Intravascular ultrasound-guided angioplasty of hemodialysis loop graft in a patient with contrast allergy.
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Casey PE, Miranda CJ, Al-Khaffaf H, and Woodhead PM
- Subjects
- Angioplasty instrumentation, Equipment Design, Female, Graft Occlusion, Vascular diagnosis, Graft Occlusion, Vascular etiology, Graft Occlusion, Vascular physiopathology, Humans, Hypersensitivity diagnosis, Middle Aged, Time Factors, Treatment Outcome, Vascular Access Devices, Vascular Patency, Angioplasty methods, Arteriovenous Shunt, Surgical adverse effects, Contrast Media adverse effects, Graft Occlusion, Vascular therapy, Hypersensitivity etiology, Renal Dialysis, Ultrasonography, Interventional instrumentation
- Abstract
Purpose: A surveillance duplex scan detected a stenosis within a left groin hemodialysis loop graft in a 57-year-old woman who was allergic to both iohexol and gadolinium contrast agents. This precluded the use of standard angioplasty treatment techniques. Intravascular ultrasound (IVUS) uses a catheter mounted with a miniaturized ultrasound probe to produce detailed cross-sectional vessel images. Clinically, it has been used in the assessment of coronary artery disease but has also supplemented standard angiography techniques in the assessment of peripheral vascular and hemodialysis access lesions., Methods: IVUS was utilized as the solitary imaging modality to identify the graft stenosis and guide the placement of a 6 mm diameter angioplasty balloon. Two areas of stenosis were successfully dilated and subsequent IVUS re-examination showed abolition of the stenosis., Results: Twelve-month follow-up surveillance scan showed that the graft remained functional with good flow rates., Conclusions: In the setting of contrast allergy, IVUS may provide a valid and safe tool in the localization and treatment of peripheral vessel stenosis, including arteriovenous fistula angioplasty. To our knowledge this is the first reported use of IVUS for hemodialysis graft salvage adopting a completely 'contrast-free' technique. More studies are required to establish the true role of IVUS in the management of hemodialysis access angioplasty, but this successful case contributes valuable information to the literature on its clinical application.
- Published
- 2014
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33. Human CFEOM1 mutations attenuate KIF21A autoinhibition and cause oculomotor axon stalling.
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Cheng L, Desai J, Miranda CJ, Duncan JS, Qiu W, Nugent AA, Kolpak AL, Wu CC, Drokhlyansky E, Delisle MM, Chan WM, Wei Y, Propst F, Reck-Peterson SL, Fritzsch B, and Engle EC
- Subjects
- Age Factors, Animals, Animals, Newborn, Axons ultrastructure, Cell Count, Disease Models, Animal, Embryo, Mammalian, Eye Diseases, Hereditary pathology, Eye Diseases, Hereditary physiopathology, Eye Movements genetics, Eye Movements physiology, Fibrosis pathology, Fibrosis physiopathology, Gene Expression Regulation genetics, Green Fluorescent Proteins genetics, Green Fluorescent Proteins metabolism, HEK293 Cells, Humans, Mice, Mice, Transgenic, Microtubule-Associated Proteins genetics, Microtubule-Associated Proteins physiology, Neural Pathways metabolism, Neural Pathways pathology, Neural Pathways ultrastructure, Ocular Motility Disorders pathology, Ocular Motility Disorders physiopathology, Oculomotor Nerve ultrastructure, Axons pathology, Eye Diseases, Hereditary genetics, Fibrosis genetics, Kinesins genetics, Kinesins metabolism, Mutation genetics, Ocular Motility Disorders genetics, Oculomotor Nerve pathology
- Abstract
The ocular motility disorder "Congenital fibrosis of the extraocular muscles type 1" (CFEOM1) results from heterozygous mutations altering the motor and third coiled-coil stalk of the anterograde kinesin, KIF21A. We demonstrate that Kif21a knockin mice harboring the most common human mutation develop CFEOM. The developing axons of the oculomotor nerve's superior division stall in the proximal nerve; the growth cones enlarge, extend excessive filopodia, and assume random trajectories. Inferior division axons reach the orbit but branch ectopically. We establish a gain-of-function mechanism and find that human motor or stalk mutations attenuate Kif21a autoinhibition, providing in vivo evidence for mammalian kinesin autoregulation. We identify Map1b as a Kif21a-interacting protein and report that Map1b⁻/⁻ mice develop CFEOM. The interaction between Kif21a and Map1b is likely to play a critical role in the pathogenesis of CFEOM1 and highlights a selective vulnerability of the developing oculomotor nerve to perturbations of the axon cytoskeleton., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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34. Microglia induce motor neuron death via the classical NF-κB pathway in amyotrophic lateral sclerosis.
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Frakes AE, Ferraiuolo L, Haidet-Phillips AM, Schmelzer L, Braun L, Miranda CJ, Ladner KJ, Bevan AK, Foust KD, Godbout JP, Popovich PG, Guttridge DC, and Kaspar BK
- Subjects
- Age Factors, Amyotrophic Lateral Sclerosis metabolism, Animals, Animals, Newborn, Astrocytes cytology, Astrocytes metabolism, Cell Communication physiology, Coculture Techniques, Disease Models, Animal, Female, Mice, Mice, Inbred Strains, Mice, Transgenic, Microglia metabolism, Motor Neurons metabolism, NF-kappa B antagonists & inhibitors, Primary Cell Culture, Signal Transduction physiology, Superoxide Dismutase genetics, Superoxide Dismutase metabolism, Superoxide Dismutase-1, Amyotrophic Lateral Sclerosis pathology, Cell Death physiology, Microglia cytology, Motor Neurons cytology, NF-kappa B metabolism
- Abstract
Neuroinflammation is one of the most striking hallmarks of amyotrophic lateral sclerosis (ALS). Nuclear factor-kappa B (NF-κB), a master regulator of inflammation, is upregulated in spinal cords of ALS patients and SOD1-G93A mice. In this study, we show that selective NF-κB inhibition in ALS astrocytes is not sufficient to rescue motor neuron (MN) death. However, the localization of NF-κB activity and subsequent deletion of NF-κB signaling in microglia rescued MNs from microglial-mediated death in vitro and extended survival in ALS mice by impairing proinflammatory microglial activation. Conversely, constitutive activation of NF-κB selectively in wild-type microglia induced gliosis and MN death in vitro and in vivo. Taken together, these data provide a mechanism by which microglia induce MN death in ALS and suggest a novel therapeutic target that can be modulated to slow the progression of ALS and possibly other neurodegenerative diseases by which microglial activation plays a role., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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35. Direct conversion of patient fibroblasts demonstrates non-cell autonomous toxicity of astrocytes to motor neurons in familial and sporadic ALS.
- Author
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Meyer K, Ferraiuolo L, Miranda CJ, Likhite S, McElroy S, Renusch S, Ditsworth D, Lagier-Tourenne C, Smith RA, Ravits J, Burghes AH, Shaw PJ, Cleveland DW, Kolb SJ, and Kaspar BK
- Subjects
- Analysis of Variance, Astrocytes metabolism, Cell Communication, Cell Culture Techniques, DNA Primers genetics, Fluorescent Antibody Technique, Humans, Models, Biological, Motor Neurons metabolism, Real-Time Polymerase Chain Reaction, Amyotrophic Lateral Sclerosis physiopathology, Astrocytes cytology, Cell Dedifferentiation physiology, Cell Differentiation physiology, Fibroblasts cytology, Motor Neurons pathology, Neural Stem Cells cytology
- Abstract
Amyotrophic lateral sclerosis (ALS) causes motor neuron degeneration, paralysis, and death. Accurate disease modeling, identifying disease mechanisms, and developing therapeutics is urgently needed. We previously reported motor neuron toxicity through postmortem ALS spinal cord-derived astrocytes. However, these cells can only be harvested after death, and their expansion is limited. We now report a rapid, highly reproducible method to convert adult human fibroblasts from living ALS patients to induced neuronal progenitor cells and subsequent differentiation into astrocytes (i-astrocytes). Non-cell autonomous toxicity to motor neurons is found following coculture of i-astrocytes from familial ALS patients with mutation in superoxide dismutase or hexanucleotide expansion in C9orf72 (ORF 72 on chromosome 9) the two most frequent causes of ALS. Remarkably, i-astrocytes from sporadic ALS patients are as toxic as those with causative mutations, suggesting a common mechanism. Easy production and expansion of i-astrocytes now enables rapid disease modeling and high-throughput drug screening to alleviate astrocyte-derived toxicity.
- Published
- 2014
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36. Dengue virus serotype-2 impairs proliferation of healthy donors' T lymphocytes.
- Author
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Fuentes-Miranda CJ, Sánchez-García FJ, Coker AR, Rojas-Espinosa O, Salinas-Tobón R, and Moreno-Altamirano MM
- Subjects
- Cells, Cultured, Humans, Interleukin-2 metabolism, NF-kappa B metabolism, NFATC Transcription Factors metabolism, Receptors, Interleukin-2 biosynthesis, Cell Proliferation, Dengue Virus immunology, Host-Pathogen Interactions, Immune Evasion, T-Lymphocytes immunology, T-Lymphocytes virology
- Abstract
Objectives: T lymphocytes are not infected by dengue virus (DENV), nevertheless it is possible that exposure to DENV may affect their function. T lymphocytes from DENV-infected individuals are impaired in their proliferative capacity, although this effect has been attributed to altered function of antigen-presenting cells rather than to an intrinsic defect on T lymphocytes. Here we analyzed whether T lymphocytes from healthy donors became impaired in their proliferative capacity following in vitro exposure to DENV serotype-2 (DENV-2), as well as the possible mechanisms for this., Methods: Isolated CD4+ and CD8+ T lymphocytes from healthy donors were in vitro exposed to DENV-2, before polyclonal activation, cell proliferation, IL-2 synthesis. IL-2Rα expression, nuclear translocation of NF-AT and NF-κB, and intracellular calcium flux were assessed., Results: In vitro exposure of both CD4+ and CD8+ T lymphocytes from healthy donors to DENV-2 impairs cell proliferation, IL-2 synthesis, and IL-2Rα (CD25) cell membrane expression. Signalling wise, exposure to DENV-2 impairs the nuclear translocation of NF-AT, downstream of intracellular calcium mobilization, as well as that of NF-κB., Conclusion: In the course of a dengue infection, direct exposure of T lymphocytes to DENV could affect cell-mediated immune responses.
- Published
- 2014
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37. Transplantation of gene-corrected motor neurons as a therapeutic strategy for spinal muscular atrophy.
- Author
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Meyer K, Miranda CJ, and Kaspar BK
- Subjects
- Animals, Disease Models, Animal, Genetic Therapy methods, Humans, Mice, Motor Neurons cytology, Survival of Motor Neuron 2 Protein genetics, Motor Neurons transplantation, Muscular Atrophy, Spinal genetics, Muscular Atrophy, Spinal therapy, Pluripotent Stem Cells cytology
- Published
- 2013
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38. Aging brain microenvironment decreases hippocampal neurogenesis through Wnt-mediated survivin signaling.
- Author
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Miranda CJ, Braun L, Jiang Y, Hester ME, Zhang L, Riolo M, Wang H, Rao M, Altura RA, and Kaspar BK
- Subjects
- Aging physiology, Animals, Astrocytes cytology, Astrocytes metabolism, Cell Differentiation physiology, Cell Growth Processes physiology, Hippocampus metabolism, Humans, Mice, Neural Stem Cells metabolism, Signal Transduction, Survivin, Wnt Signaling Pathway, Hippocampus cytology, Inhibitor of Apoptosis Proteins metabolism, Neural Stem Cells cytology, Repressor Proteins metabolism, Wnt Proteins metabolism
- Abstract
Accumulating evidence suggests that adult hippocampal neurogenesis relies on the controlled and continued proliferation of neural progenitor cells (NPCs). With age, neurogenesis decreases through mechanisms that remain unclear but are believed to involve changes in the NPC microenvironment. Here, we provide evidence that NPC proliferation in the adult brain is in part regulated by astrocytes via Wnt signaling and that this cellular cross-talk is modified in the aging brain, leading to decreased proliferation of NPCs. Furthermore, we show that astrocytes regulate the NPC cell cycle by acting on the expression levels of survivin, a known mitotic regulator. Among cell cycle genes found down-regulated in aged NPCs, survivin was the only one that restored NPC proliferation in the aged brain. Our results provide a mechanism for the gradual loss of neurogenesis in the brain associated with aging and suggest that targeted modulation of survivin expression directly or through Wnt signaling could be used to stimulate adult neurogenesis., (© 2012 The Authors. Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.)
- Published
- 2012
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39. Recombinant human activated protein C as a disease modifier in severe acute pancreatitis: systematic review of current evidence.
- Author
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Miranda CJ, Babu BI, and Siriwardena AK
- Subjects
- Acute Disease, Animals, Disease Models, Animal, Humans, MEDLINE, Multiple Organ Failure etiology, Pancreatitis complications, Randomized Controlled Trials as Topic, Rats, Recombinant Proteins therapeutic use, Translational Research, Biomedical, Treatment Failure, Fibrinolytic Agents therapeutic use, Multiple Organ Failure drug therapy, Pancreatitis drug therapy, Protein C therapeutic use
- Abstract
Background: The severity of organ failure caused by acute pancreatitis (AP) is the most important determinant of mortality in the disease. Recombinant human activated protein C (Drotrecogin Alfa; Xigris, APC, rhAPC) is the first drug to show a decrease in all-cause mortality due to multiple organ failure caused by sepsis. As the systemic inflammatory response syndrome (SIRS) that causes organ failure in early AP is similar to that caused by severe sepsis, the use of rhAPC in the management of AP has been investigated in experimental and clinical studies which are collated in this review., Methods: A literature review of published material identified from MEDLINE and EMBASE databases, for the period from January 1985 to January 2011, reporting rhAPC usage in AP., Results: 3 of 4 experimental studies reported an improvement in outcome in animals with AP given rhAPC. The clinical randomized trial showed no improvement in outcome in the treatment arm., Conclusion: The experimental evidence of disease amelioration in AP following intervention with rhAPC has not translated to the small clinical RCT. Given that there were only 16 patients in the treatment arm, further clinical evaluation is justified., (Copyright © 2012 IAP and EPC. Published by Elsevier B.V. All rights reserved.)
- Published
- 2012
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40. Intra-abdominal pressure and abdominal perfusion pressure early in severe acute pancreatitis misses the forest for the trees.
- Author
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Miranda CJ
- Subjects
- Female, Humans, Male, Abdominal Cavity physiopathology, Pancreatitis physiopathology, Pressure, Severity of Illness Index
- Published
- 2011
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41. Rapid and efficient generation of functional motor neurons from human pluripotent stem cells using gene delivered transcription factor codes.
- Author
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Hester ME, Murtha MJ, Song S, Rao M, Miranda CJ, Meyer K, Tian J, Boulting G, Schaffer DV, Zhu MX, Pfaff SL, Gage FH, and Kaspar BK
- Subjects
- Cell Differentiation, Cell Line, Embryonic Stem Cells cytology, Gene Expression Profiling, Humans, Motor Neurons metabolism, Reverse Transcriptase Polymerase Chain Reaction, Transcription Factors genetics, Motor Neurons cytology, Pluripotent Stem Cells pathology, Transcription Factors metabolism
- Abstract
Stem cell-derived motor neurons (MNs) are increasingly utilized for modeling disease in vitro and for developing cellular replacement strategies for spinal cord injury and diseases such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Human embryonic stem cell (hESC) differentiation into MNs, which involves retinoic acid (RA) and activation of the sonic hedgehog (SHH) pathway is inefficient and requires up to 60 days to develop MNs with electrophysiological properties. This prolonged differentiation process has hampered the use of hESCs, in particular for high-throughput screening. We evaluated the MN gene expression profile of RA/SHH-differentiated hESCs to identify rate-limiting factors involved in MN development. Based on this analysis, we developed an adenoviral gene delivery system encoding for MN inducing transcription factors: neurogenin 2 (Ngn2), islet-1 (Isl-1), and LIM/homeobox protein 3 (Lhx3). Strikingly, delivery of these factors induced functional MNs with mature electrophysiological properties, 11-days after gene delivery, with >60-70% efficiency from hESCs and human induced pluripotent stem cells (hiPSCs). This directed programming approach significantly reduces the time required to generate electrophysiologically-active MNs by approximately 30 days in comparison to conventional differentiation techniques. Our results further exemplify the potential to use transcriptional coding for rapid and efficient production of defined cell types from hESCs and hiPSCs.
- Published
- 2011
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42. Astrocytes from familial and sporadic ALS patients are toxic to motor neurons.
- Author
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Haidet-Phillips AM, Hester ME, Miranda CJ, Meyer K, Braun L, Frakes A, Song S, Likhite S, Murtha MJ, Foust KD, Rao M, Eagle A, Kammesheidt A, Christensen A, Mendell JR, Burghes AH, and Kaspar BK
- Subjects
- Amyotrophic Lateral Sclerosis pathology, Animals, Astrocytes metabolism, Biomarkers, Cell Differentiation, Cell Line, Coculture Techniques, Disease Models, Animal, Embryonic Stem Cells cytology, Embryonic Stem Cells drug effects, Embryonic Stem Cells metabolism, Gene Expression Regulation, Humans, Immunohistochemistry, Mesenchymal Stem Cells cytology, Mesenchymal Stem Cells drug effects, Mesenchymal Stem Cells metabolism, Mice, Motor Neurons cytology, Motor Neurons drug effects, Mutation, Sequence Analysis, DNA, Signal Transduction, Superoxide Dismutase genetics, Superoxide Dismutase metabolism, Superoxide Dismutase-1, Amyotrophic Lateral Sclerosis genetics, Astrocytes pathology, Motor Neurons pathology
- Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease, with astrocytes implicated as contributing substantially to motor neuron death in familial (F)ALS. However, the proposed role of astrocytes in the pathology of ALS derives in part from rodent models of FALS based upon dominant mutations within the superoxide dismutase 1 (SOD1) gene, which account for <2% of all ALS cases. Their role in sporadic (S)ALS, which affects >90% of ALS patients, remains to be established. Using astrocytes generated from postmortem tissue from both FALS and SALS patients, we show that astrocytes derived from both patient groups are similarly toxic to motor neurons. We also demonstrate that SOD1 is a viable target for SALS, as its knockdown significantly attenuates astrocyte-mediated toxicity toward motor neurons. Our data highlight astrocytes as a non-cell autonomous component in SALS and provide an in vitro model system to investigate common disease mechanisms and evaluate potential therapies for SALS and FALS.
- Published
- 2011
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43. Two factor reprogramming of human neural stem cells into pluripotency.
- Author
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Hester ME, Song S, Miranda CJ, Eagle A, Schwartz PH, and Kaspar BK
- Subjects
- Cell Differentiation, Cell Lineage, Germ Cells cytology, Humans, Karyotyping, Kruppel-Like Factor 4, Microscopy, Fluorescence methods, Neurons metabolism, Proto-Oncogene Proteins c-myc metabolism, Reverse Transcriptase Polymerase Chain Reaction, Frontal Lobe embryology, Gene Expression Regulation, Kruppel-Like Transcription Factors metabolism, Neurons cytology, Octamer Transcription Factor-3 metabolism, Stem Cells cytology
- Abstract
Background: Reprogramming human somatic cells to pluripotency represents a valuable resource for the development of in vitro based models for human disease and holds tremendous potential for deriving patient-specific pluripotent stem cells. Recently, mouse neural stem cells (NSCs) have been shown capable of reprogramming into a pluripotent state by forced expression of Oct3/4 and Klf4; however it has been unknown whether this same strategy could apply to human NSCs, which would result in more relevant pluripotent stem cells for modeling human disease., Methodology and Principal Findings: Here, we show that OCT3/4 and KLF4 are indeed sufficient to induce pluripotency from human NSCs within a two week time frame and are molecularly indistinguishable from human ES cells. Furthermore, human NSC-derived pluripotent stem cells can differentiate into all three germ lineages both in vitro and in vivo., Conclusions/significance: We propose that human NSCs represent an attractive source of cells for producing human iPS cells since they only require two factors, obviating the need for c-MYC, for induction into pluripotency. Thus, in vitro human disease models could be generated from iPS cells derived from human NSCs.
- Published
- 2009
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44. Gene expression profiling in frataxin deficient mice: microarray evidence for significant expression changes without detectable neurodegeneration.
- Author
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Coppola G, Choi SH, Santos MM, Miranda CJ, Tentler D, Wexler EM, Pandolfo M, and Geschwind DH
- Subjects
- Animals, Cell Line, Central Nervous System pathology, Central Nervous System physiopathology, Disease Models, Animal, Female, Friedreich Ataxia metabolism, Friedreich Ataxia physiopathology, Gene Expression Profiling, Humans, Male, Mice, Mice, Knockout, Mitochondria genetics, Mitochondria metabolism, Mutation genetics, Nerve Degeneration metabolism, Nerve Degeneration physiopathology, Oligonucleotide Array Sequence Analysis, Phenotype, Spinal Cord metabolism, Spinal Cord pathology, Spinal Cord physiopathology, Frataxin, Central Nervous System metabolism, Friedreich Ataxia genetics, Gene Expression Regulation genetics, Genetic Predisposition to Disease genetics, Iron-Binding Proteins genetics, Nerve Degeneration genetics
- Abstract
Friedreich's ataxia (FRDA) is caused by reduction of frataxin levels to 5-35%. To better understand the biochemical sequelae of frataxin reduction, in absence of the confounding effects of neurodegeneration, we studied the gene expression profile of a mouse model expressing 25-36% of the normal frataxin levels, and not showing a detectable phenotype or neurodegenerative features. Despite having no overt phenotype, a clear microarray gene expression phenotype was observed. This phenotype followed the known regional susceptibility in this disease, most changes occurring in the spinal cord. Additionally, gene ontology analysis identified a clear mitochondrial component, consistent with previous findings. We were able to confirm a subset of changes in fibroblast cell lines from patients. The identification of a core set of genes changing early in the FRDA pathogenesis can be a useful tool in both clarifying the disease process and in evaluating new therapeutic strategies.
- Published
- 2006
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45. Frataxin overexpressing mice.
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Miranda CJ, Santos MM, Ohshima K, Tessaro M, Sequeiros J, and Pandolfo M
- Subjects
- Animals, DNA Primers, Erythrocyte Count, Friedreich Ataxia blood, Hematocrit, Hematopoiesis genetics, Humans, Iron metabolism, Mice, Mice, Mutant Strains, Mice, Transgenic, Polymerase Chain Reaction, Transferrin metabolism, Frataxin, Friedreich Ataxia genetics, Iron-Binding Proteins genetics
- Abstract
Friedreich ataxia, the most common autosomal recessive ataxia, is caused by frataxin deficiency. Reduction of frataxin has been associated with iron accumulation and sensitivity to iron induced oxidative stress. To better understand the function of frataxin, transgenic mice (tgFxn) overexpressing human frataxin were generated. Iron metabolism parameters in tgFxn were normal and no signs of ataxia or other obvious abnormalities were observed, indicating that overexpression of frataxin in mouse is innocuous. Several hypotheses for frataxin function were evaluated in tgFxn mice. In particular, we observed that TgFxn mice show an altered response during hematopoietic differentiation, suggesting that frataxin may directly affect heme synthesis.
- Published
- 2004
- Full Text
- View/download PDF
46. Genomic structure, promoter activity, and developmental expression of the mouse homologue of the Machado-Joseph disease (MJD) gene.
- Author
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Costa MC, Gomes-da-Silva J, Miranda CJ, Sequeiros J, Santos MM, and Maciel P
- Subjects
- 5' Flanking Region genetics, Amino Acid Sequence, Animals, Ataxin-3, Base Sequence, Cell Differentiation, Cell Line, Cloning, Molecular, DNA, Complementary genetics, Embryo, Mammalian metabolism, Mice, Mice, Inbred C57BL, MyoD Protein genetics, MyoD Protein metabolism, Nerve Tissue Proteins metabolism, Nuclear Proteins, Protein Binding, Repressor Proteins, Sequence Alignment, Transcription Factors, Gene Expression Regulation, Developmental, Nerve Tissue Proteins genetics, Promoter Regions, Genetic genetics
- Abstract
Machado-Joseph disease (MJD) is a neurodegenerative disorder, caused by the expansion of the (CAG)n tract in the MJD gene. This encodes the protein ataxin-3, of unknown function. The mouse Mjd gene has a structure similar to that of its human counterpart and it also contains a TATA-less promoter. Its 5' flanking region contains conserved putative binding regions for transcription factors Sp1, USF, Arnt, Max, E47, and MyoD. Upon differentiation of P19 cells, the Mjd gene promoter is preferentially activated in endodermal and mesodermal derivatives, including cardiac and skeletal myocytes; and less so in neuronal precursors. Mouse ataxin-3 is ubiquitously expressed during embryonic development and in the adult, with strong expression in regions of the CNS affected in MJD. It is particularly abundant in all types of muscle and in ciliated epithelial cells, suggesting that it may be associated with the cytoskeleton and may have an important function in cell structure and/or motility.
- Published
- 2004
- Full Text
- View/download PDF
47. Contributions of beta2-microglobulin-dependent molecules and lymphocytes to iron regulation: insights from HfeRag1(-/-) and beta2mRag1(-/-) double knock-out mice.
- Author
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Miranda CJ, Makui H, Andrews NC, and Santos MM
- Subjects
- Animals, Genes, RAG-1, Hemochromatosis genetics, Hemochromatosis Protein, Homeostasis, Lymphocytes physiology, Mice, Mice, Knockout, Myocardium metabolism, Pancreas metabolism, beta 2-Microglobulin deficiency, beta 2-Microglobulin genetics, Histocompatibility Antigens Class I genetics, Homeodomain Proteins genetics, Iron metabolism, Membrane Proteins deficiency, Membrane Proteins genetics, Mutation, beta 2-Microglobulin physiology
- Abstract
Genetic causes of hereditary hemochromatosis (HH) include mutations in the HFE gene, coding for a beta2-microglobulin (beta2m)-associated major histocompatibility complex class I-like protein. However, iron accumulation in patients with HH can be highly variable. Previously, analysis of beta2mRag1(-/-) double-deficient mice, lacking all beta2m-dependent molecules and lymphocytes, demonstrated increased iron accumulation in the pancreas and heart compared with beta2m single knock-out mice. To evaluate whether the observed phenotype in beta2mRag1(-/-) mice was due solely to the absence of Hfe or to other beta2m-dependent molecules, we generated HfeRag1(-/-) double-deficient mice. Our studies revealed that introduction of Rag1 deficiency in Hfe knock-out mice leads to heightened iron overload, mainly in the liver, whereas the heart and pancreas are relatively spared compared with beta2mRag1(-/-) mice. These results suggest that other beta2m-interacting protein(s) may be involved in iron regulation and that in the absence of functional Hfe molecules lymphocyte numbers may influence iron overload severity.
- Published
- 2004
- Full Text
- View/download PDF
48. Hfe deficiency increases susceptibility to cardiotoxicity and exacerbates changes in iron metabolism induced by doxorubicin.
- Author
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Miranda CJ, Makui H, Soares RJ, Bilodeau M, Mui J, Vali H, Bertrand R, Andrews NC, and Santos MM
- Subjects
- Alanine Transaminase blood, Animals, Aspartate Aminotransferases blood, Creatine Kinase blood, Female, Genetic Predisposition to Disease, Hemochromatosis Protein, Iron Metabolism Disorders genetics, Iron Metabolism Disorders mortality, Liver metabolism, Mice, Mice, Mutant Strains, Mitochondria metabolism, Myocardium metabolism, Survival Rate, Transferrin metabolism, Antibiotics, Antineoplastic toxicity, Doxorubicin toxicity, Histocompatibility Antigens Class I genetics, Iron metabolism, Iron Metabolism Disorders chemically induced, Membrane Proteins genetics
- Abstract
The clinical use of doxorubicin (DOX), an anthracycline chemotherapeutic agent, is limited by cardiotoxicity. The possible involvement of iron in DOX-induced cardiotoxicity became evident from studies in which iron chelators were shown to be cardioprotective. Iron overload is found in hereditary hemochromatosis, a genetic disorder prevalent in individuals of European descent. We hypothesized that Hfe deficiency may increase susceptibility to DOX-induced toxicity. Acute cardiotoxicity and iron changes were studied after treatment with DOX in Hfe knock-out (Hfe-/-) mice and wild-type mice. DOX-induced iron metabolism changes were intensified in Hfe-/- mice, which accumulated significantly more iron in the heart, liver, and pancreas, but less in the spleen compared with wild-type mice. In addition, Hfe-deficient mice exhibited significantly greater sensitivity to DOX-induced elevations in serum creatine kinase and aspartate aminotransferase. Increased mortality after chronic DOX treatment was observed in Hfe-/- mice and Hfe+/-mice compared with wild-type mice. DOX-treated Hfe-/- mice had a higher degree of mitochondrial damage and iron deposits in the heart than did wild-type mice. These data demonstrate that Hfe deficiency in mice increases susceptibility to DOX-induced cardiotoxicity and suggest that genetic mutations related to defects in iron metabolism may contribute to its cardiotoxicity in humans.
- Published
- 2003
- Full Text
- View/download PDF
49. Iron metabolism in mice with partial frataxin deficiency.
- Author
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Santos MM, Miranda CJ, Levy JE, Montross LK, Cossée M, Sequeiros J, Andrews N, Koenig M, and Pandolfo M
- Subjects
- Animals, Disease Models, Animal, Friedreich Ataxia genetics, Hemochromatosis genetics, Hemochromatosis metabolism, Introns, Iron Deficiencies, Iron-Binding Proteins metabolism, Liver metabolism, Liver pathology, Mice, Mice, Knockout, Reference Values, Trinucleotide Repeats, Frataxin, Iron metabolism, Iron-Binding Proteins genetics
- Abstract
Friedreich ataxia (FRDA), the most common autosomal recessive inherited ataxic disorder, is the consequence of deficiency of the mitochondrial protein frataxin, typically caused by homozygous intronic GAA expansions in the corresponding gene. The yeast frataxin homologue (yfh1p) is required for cellular respiration. Yfh1p appears to regulate mitochondrial iron homeostasis and protect from free radical toxicity. Complete loss of frataxin in knockout mice leads to early embryonic lethality, indicating an important role for frataxin during development. Heterozygous littermates with partial frataxin deficiency are apparently healthy and have no obvious phenotype. Here we evaluate iron metabolism and sensitivity to dietary and parenteral iron loading in heterozygote frataxin knockout mice (Fx(+/-)). Iron concentrations in the liver, heart, pancreas and spleen, and cellular iron distribution patterns were compared between wild type and Fx(+/-) mice. Response to parenteral iron challenge was not different between Fx(+/-) mice and wild type littermates, while sporadic iron deposits were observed in the hearts of dietary iron-loaded Fx(+/-) mice. Finally, we evaluated the effect of partial frataxin deficiency on susceptibility to cardiac damage in the mouse model of hereditary hemochromatosis (HH), the Hfe knockout mice. HH, an iron overload disease, is one of the most frequent genetic diseases in populations of European origin. By breeding Hfe(-/-) with Fx(+/-) mice, we obtained compound mutant mice lacking both Hfe and one frataxin allele. Sparse iron deposits in areas of mild to moderate cardiac fibrosis were found in the majority of these mice. However, they did not develop any neurological symptoms. Our studies indicate an association between frataxin deficiency, iron deposits and cardiac fibrosis, but no obvious association between iron accumulation and neurodegeneration similar to FRDA could be detected in our model. In addition, these results suggest that frataxin mutations may have a modifier role in HH, that predisposes to cardiomyopathy.
- Published
- 2003
- Full Text
- View/download PDF
50. Frataxin knockin mouse.
- Author
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Miranda CJ, Santos MM, Ohshima K, Smith J, Li L, Bunting M, Cossée M, Koenig M, Sequeiros J, Kaplan J, and Pandolfo M
- Subjects
- Alleles, Animals, Homeostasis, Iron metabolism, Mice, Mitochondria metabolism, Frataxin, Friedreich Ataxia genetics, Iron-Binding Proteins, Mice, Mutant Strains, Phosphotransferases (Alcohol Group Acceptor) genetics, Trinucleotide Repeat Expansion genetics
- Abstract
Friedreich ataxia is the consequence of frataxin deficiency, most often caused by a GAA repeat expansion in intron 1 of the corresponding gene. Frataxin is a mitochondrial protein involved in iron homeostasis. As an attempt to generate a mouse model of the disease, we introduced a (GAA)(230) repeat within the mouse frataxin gene by homologous recombination. GAA repeat knockin mice were crossed with frataxin knockout mice to obtain double heterozygous mice expressing 25-36% of wild-type frataxin levels. These mice were viable and did not develop anomalies of motor coordination, iron metabolism or response to iron loading. Repeats were meiotically and mitotically stable.
- Published
- 2002
- Full Text
- View/download PDF
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