162 results on '"Keegan BM"'
Search Results
2. A case of necrotizing myopathy with proximal weakness and cardiomyopathy.
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Matthews E, Plotz PH, Portaro S, Parton M, Elliott P, Humbel RL, Holton JL, Keegan BM, Hanna MG, Matthews, E, Plotz, P H, Portaro, S, Parton, M, Elliott, P, Humbel, R L, Holton, J L, Keegan, B M, and Hanna, M G
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- 2012
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3. Solitary sclerosis: progressive myelopathy from solitary demyelinating lesion.
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Schmalstieg WF, Keegan BM, Weinshenker BG, Schmalstieg, William F, Keegan, B Mark, and Weinshenker, Brian G
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- 2012
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4. Primary intramedullary spinal cord lymphoma.
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Flanagan EP, O'Neill BP, Porter AB, Lanzino G, Haberman TM, and Keegan BM
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- 2011
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5. A middle-aged woman with nausea, weight loss, and orthostatic hypotension.
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Singer W, Yung IO, Wollmann R, Kelly T, and Keegan BM
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- 2011
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6. Paraneoplastic isolated myelopathy: Clinical course and neuroimaging clues.
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Flanagan EP, McKeon A, Lennon VA, Kearns J, Weinshenker BG, Krecke KN, Matiello M, Keegan BM, Mokri B, Aksamit AJ, and Pittock SJ
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- 2011
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7. A 49-year-old woman with progressive shortness of breath.
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Amato AA, Leep Hunderfund AN, Selcen D, and Keegan BM
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- 2011
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8. Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS)
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Pittock SJ, Debruyne J, Krecke KN, Giannini C, van den Ameele J, De Herdt V, McKeon A, Fealey RD, Weinshenker BG, Aksamit AJ, Krueger BR, Shuster EA, and Keegan BM
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- 2010
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9. A 74-year-old woman with progressive right-hand tremor and inability to use her right side.
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Kertesz A, Fealey RD, Keegan BM, and Parisi JE
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- 2009
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10. A 54-year-old woman with progressive gait disturbance and MRI abnormalities.
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Hochberg FH, Rodriguez FJ, Atkinson JL, Shaw EG, Keegan BM, and Kantarci OH
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- 2009
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11. A 63-year-old woman with urinary incontinence and progressive gait disorder.
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Lossos A, Klein CJ, McEvoy KM, and Keegan BM
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- 2009
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12. A 52-year-old man with progressive left-sided weakness and white matter disease.
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Fleming JO, Keegan BM, and Parisi JE
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- 2007
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13. A 46-year-old woman with severe weakness following acute respiratory distress syndrome.
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Waclawik AJ, Selcen D, and Keegan BM
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- 2007
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14. An 81-year-old man with imbalance and memory impairment.
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Golbe LI, Boeve BF, Keegan BM, and Parisi JE
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- 2007
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15. 61-year-old woman with shortness of breath after surgery.
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Mowzoon N and Keegan BM
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- 2004
16. Atypical acute hemorrhagic leukoencephalitis (Hurst's disease) presenting with focal hemorrhagic brainstem lesion.
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Abou Zeid NE, Burns JD, Wijdicks EF, Giannini C, Keegan BM, Abou Zeid, Nuhad E, Burns, Joseph D, Wijdicks, Eelco F M, Giannini, Caterina, and Keegan, B Mark
- Abstract
Background: Acute hemorrhagic leukoencephalitis (AHL; Hurst's disease) is a rare, severe, inflammatory CNS disease that is typically diffuse, multifocal and associated with petechial hemorrhage. The objective of this study is to report the clinical, radiologic, and pathologic findings in a fatal AHL case with focal brainstem involvement and gross hemorrhage.Methods: Patient evaluation in a tertiary neurointensive care unit with serial brain magnetic resonance imaging (MRI) and neuropathological examination on autopsy were performed.Results: The patient presented with mild, then rapidly worsening, brainstem impairment to a locked-in syndrome. Brain MRI demonstrated an isolated gadolinium enhancing brainstem lesion that enlarged dramatically over weeks and was associated with gross hemorrhage and necrosis. The patient died despite aggressive treatment with intravenous corticosteroids and plasma exchange. Autopsy demonstrated the isolated severe necrotic lesion consistent with AHL.Conclusions: AHL may present as a solitary brainstem lesion with gross hemorrhage and should be considered in patients with isolated enhancing brainstem lesions. AHL may be fatal even despite early, aggressive immunomodulatory therapy. [ABSTRACT FROM AUTHOR]- Published
- 2010
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17. A randomized controlled crossover trial of aspirin for fatigue in multiple sclerosis.
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Wingerchuk DM, Benarroch EE, O'Brien PC, Keegan BM, Lucchinetti CF, Noseworthy JH, Weinshenker BG, and Rodriguez M
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- 2005
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18. Contrasting effects of IFNbeta and IVIG in children with central and peripheral demyelination.
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Pirko I, Kuntz NL, Patterson M, Keegan BM, Weinshenker BG, Rodriguez M, Pirko, I, Kuntz, N L, Patterson, M, Keegan, B M, Weinshenker, B G, and Rodriguez, M
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- 2003
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19. Laquinimod, a new oral drug for multiple sclerosis.
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Keegan BM and Weinshenker BG
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- 2008
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20. A case of endocrinologic crisis in a woman with subacute blindness.
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Burrus TM, Drake MT, Sanderson SO, and Keegan BM
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- 2010
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21. Acquired progressive ataxia and palatal tremor: Importance of MRI evidence of hemosiderin deposition and vascular malformations.
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Kumar N, Eggers SD, Milone M, and Keegan BM
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- 2011
22. Multiple sclerosis in Somali Americans: Nature or nurture?
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Nathoo N, Neyal N, Atkinson EJ, Weinshenker BG, Tillema JM, Keegan BM, Pittock SJ, Tobin WO, Flanagan EP, Gavrilova R, Toledano M, Young N, Truitt K, Okuda DT, Zeydan B, and Kantarci OH
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- Adult, Female, Humans, Male, Middle Aged, Young Adult, Age of Onset, Immunologic Factors therapeutic use, Minnesota epidemiology, Retrospective Studies, Somalia ethnology, White People, White, East African People, Black or African American, Emigrants and Immigrants, Multiple Sclerosis ethnology, Multiple Sclerosis drug therapy
- Abstract
Background: Differences in the MS course between White and Black populations is well accepted. The existence of a large Somali immigrant population in Minnesota facilitates a study of MS characteristics in this immigrant native African population. The objective of this study was to compare Somali American (SA), African American (AA), and White American (WA) persons with MS (pwMS) regarding clinical features and disease modifying therapy (DMT) use., Methods: This single center (Mayo Clinic) geographically-restricted retrospective cohort study (residing within 250 miles of Rochester, MN, USA) included participants seen before May 2023. Age at immigration to the USA; age at MS onset; DMT use/type; MS phase/phenotype; age at progressive MS (PMS) onset; and proportion with severe MS (expanded disability status scale-EDSS ≥6) were examined., Results: 18 SApwMS, 92 AApwMS, and 94 WApwMS were included. Of the 15 SApwMS not born in USA, 3/15 immigrated pre-puberty, 3/15 peri‑puberty, 8/15 post-puberty, and 1/15 at an unknown date. SApwMS were younger at MS onset (median years, interquartile range (IQR)=25, 22-33 vs. AApwMS: 31, 25-38; p = 0.049 vs. WApwMS: 35, 27-41; p = 0.022). DMT use frequencies were 13/19 SApwMS, 69/92 AApwMS, 80/94 WApwMS (p > 0.05). SApwMS were treated with DMT earlier than AApwMS (HR 2.16, p = 0.012) and WApwMS (HR 1.86, p = 0.041). SApwMS were less commonly treated with natalizumab (SApwMS 0 %, AApwMS 13 %, WApwMS 25 %; p = 0.035) and anti-CD20 therapies (SApwMS 23 %, AApwMS 23 %, WApwMS 48 %; p = 0.005). PMS occurred in 3/19 SApwMS, 28/92 AApwMS and 29/94 WApwMS (p > 0.05). Age of PMS onset in SApwMS (47 years, 34-57) was similar to WApwMS (47 years, 31-71; p > 0.05) but older than AApwMS (41 years, 18-7; p = 0.008)., Conclusions: SApwMS that recently immigrated to the USA have similar disease course to WApwMS, and better than AApwMS from the same geographical region., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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23. MR Imaging Features of Critical Spinal Demyelinating Lesions Associated with Progressive Motor Impairment.
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Keegan BM, Messina SA, Hanson D, Holmes D, Camp J, Sechi E, Nayak S, Barakat B, Ahmad R, Mandrekar J, Harmsen WS, Kantarci O, Weinshenker BG, and Flanagan EP
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- Humans, Male, Female, Retrospective Studies, Middle Aged, Adult, Disease Progression, Demyelinating Diseases diagnostic imaging, Demyelinating Diseases pathology, Spinal Cord diagnostic imaging, Spinal Cord pathology, Aged, Multiple Sclerosis, Chronic Progressive diagnostic imaging, Multiple Sclerosis, Chronic Progressive pathology, Magnetic Resonance Imaging methods
- Abstract
Background and Purpose: Progressive MS is typically heralded by a myelopathic pattern of asymmetric progressive motor weakness. Focal individual "critical" demyelinating spinal cord lesions anatomically associated with progressive motor impairment may be a compelling explanation for this clinical presentation as described in progressive solitary sclerosis (single CNS demyelinating lesion), progressive demyelination with highly restricted MR imaging lesion burden (2-5 total CNS demyelinating lesions; progressive paucisclerotic MS), and progressive, exclusively unilateral hemi- or monoparetic MS (>5 CNS demyelinating progressive unilateral hemi- or monoparetic MS [PUHMS] lesions). Critical demyelinating lesions appear strikingly similar across these cohorts, and we describe their specific spinal cord MR imaging characteristics., Materials and Methods: We performed a retrospective, observational MR imaging study comparing spinal cord critical demyelinating lesions anatomically associated with progressive motor impairment with any additional "noncritical" (not anatomically associated with progressive motor impairment) spinal cord demyelinating lesions. All spinal cord MR images (302 cervical and 91 thoracic) were reviewed by an experienced neuroradiologist with final radiologic assessment on the most recent MR imaging. Anatomic association with clinical progressive motor impairment was confirmed independently by MS subspecialists., Results: Ninety-one individuals (PUHMS, 37 [41%], progressive paucisclerosis 35 [38%], progressive solitary sclerosis 19 [21%]) with 91 critical and 98 noncritical spinal cord MR imaging demyelinating lesions were evaluated. MR imaging characteristics that favored critical spinal cord demyelinating lesions over noncritical lesions included moderate-to-severe, focal, lesion-associated spinal cord atrophy: 41/91 (45%) versus 0/98 (0%) (OR, 161.91; 9.43 to >999.9); lateral column axial location (OR, 10.43; 3.88-28.07); central region (OR, 3.23; 1.78-5.88); ventral column (OR, 2.98; 1.55-5.72); and larger lesion size of the axial width (OR, 2.01;1.49-2.72), transverse axial size (OR, 1.66; 1.36-2.01), or lesion area (OR, 1.14; 1.08-1.2). Multiple regression analysis revealed focal atrophy and lateral axial location as having the strongest association with critical demyelinating lesions., Conclusions: Focal, lesion-associated atrophy, lateral column axial location, and larger lesion size are spinal cord MR imaging characteristics of critical demyelinating lesions. The presence of critical demyelinating lesions should be sought as these features may be associated with the development of progressive motor impairment in MS., (© 2024 by American Journal of Neuroradiology.)
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- 2024
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24. Elucidation of novel TRAP1-Selective inhibitors that regulate mitochondrial processes.
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Merfeld T, Peng S, Keegan BM, Crowley VM, Brackett CM, Gutierrez A, McCann NR, Reynolds TS, Rhodes MC, Byrd KM, Deng J, Matts RL, and Blagg BSJ
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- Humans, Protein Binding, Protein Isoforms metabolism, HSP90 Heat-Shock Proteins metabolism
- Abstract
Hsp90 isoform-selective inhibitors represent a new paradigm for novel anti-cancer drugs as each of the four isoforms have specific cellular localization, function, and client proteins. The mitochondrial isoform, TRAP1, is the least understood member of the Hsp90 family due to the lack of small molecule tools to study its biological function. Herein, we report novel TRAP1-selective inhibitors used to interrogate TRAP1's biological function along with co-crystal structures of such compounds bound to the N-terminus of TRAP1. Solution of the co-crystal structure allowed for a structure-based approach that resulted in compound 36, which is a 40 nM inhibitor with >250-fold TRAP1 selectivity over Grp94, the isoform with the highest structural similarity to TRAP1 within the N-terminal ATP binding site. Lead compounds 35 and 36 were found to selectively induce TRAP1 client protein degradation without inducing the heat shock response or disrupting Hsp90-cytosolic clients. They were also shown to inhibit OXPHOS, alter cellular metabolism towards glycolysis, disrupt TRAP1 tetramer stability, and disrupt the mitochondrial membrane potential., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Brian blagg has patent pending to University of Notre Dame. Junpeng Dend and Robert Matts : none., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)
- Published
- 2023
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25. Frequency of demyelinating disease activity following immune checkpoint inhibitor cancer immunotherapy.
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Hasan S, Zorio O, Keegan BM, Weinshenker BG, Flanagan EP, Tobin WO, Kantarci OH, Toledano M, Pittock SJ, Lopez-Chiriboga S, Zekeridou A, and Valencia-Sanchez C
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- Humans, Immune Checkpoint Inhibitors adverse effects, Neoplasms drug therapy, Demyelinating Diseases chemically induced
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- 2023
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26. Coexistence of multiple sclerosis and spinocerebellar ataxia type-8.
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Neyal N, Keegan BM, Kantarci OH, and Zeydan B
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- Humans, Male, Adult, Ataxia genetics, Ataxia pathology, Brain pathology, Spinal Cord, Multiple Sclerosis complications, Multiple Sclerosis diagnosis, Multiple Sclerosis genetics, Multiple Sclerosis pathology, Spinocerebellar Degenerations complications, Spinocerebellar Degenerations diagnosis, Spinocerebellar Degenerations genetics, Spinocerebellar Degenerations pathology
- Abstract
Cerebellar dysfunction is likely to cause severe and treatment-resistant disability in multiple sclerosis (MS). Certain spinocerebellar ataxia (SCA)-related alleles can increase MS susceptibility, and channel polymorphisms can impact disability measures. Following an index patient with the coexistence of MS and SCA Type-8 (SCA8) in the MS clinic, an institutional engine search for MS and hereditary ataxia coexistence was conducted but did not reveal any other cases. This extremely rare coexistence of MS and SCA8 in our index patient may be incidental; however, a yet-to-be-identified contribution of coexistent hereditary ataxia(s) to the susceptibility of a prominent progressive ataxia MS phenotype cannot be ruled out.
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- 2023
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27. Spinal cord and brain corticospinal tract lesions are associated with motor progression in tumefactive multiple sclerosis.
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Jackson-Tarlton CS, Keegan BM, Fereidan-Esfahani M, Barakat BO, Decker PA, Lucchinetti CF, Eckel-Passow J, and Tobin WO
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- Humans, Pyramidal Tracts diagnostic imaging, Retrospective Studies, Disease Progression, Spinal Cord diagnostic imaging, Spinal Cord pathology, Brain diagnostic imaging, Brain pathology, Magnetic Resonance Imaging methods, Multiple Sclerosis complications, Multiple Sclerosis diagnostic imaging, Multiple Sclerosis pathology, Spinal Cord Diseases diagnostic imaging, Spinal Cord Diseases pathology
- Abstract
Background: Spinal cord lesions have been associated with progressive disease in individuals with typical relapsing remitting MS (RRMS)., Objective: In the current study, we aimed to determine if progressive disease is associated with spinal cord lesions in those with tumefactive multiple sclerosis (MS)., Methods: Retrospective chart review of individuals presenting to Mayo Clinic with tumefactive MS with spinal cord MRIs available (n=159). Clinical data were extracted by chart review. Brain and spinal cord MRIs were reviewed to characterize the tumefactive demyelinating lesion(s) and assess the burden of spinal cord disease., Results: A total of 69 (43%) had spinal cord lesions. Progressive demyelinating disease was documented in 13 (8%); the majority (11/13) with secondary progressive disease. The method of progression was myelopathic in 8/13 (62%), cognitive in 3/13 (23%), motor from a supratentorial lesion in 2/13 (16%). EDSS at last follow-up was higher in those with progression than those without (median 6.0 (2.0-10.0) vs. 2.5 (0-10.0), p = < 0.001). Progressive demyelinating disease occurred in a minority., Conclusions: Patients with progression typically experienced progressive motor impairment, and this occurred exclusively in individuals with lesions in the corticospinal tracts of the brain and/or the spinal cord., Competing Interests: Declaration of Competing Interest The authors report no disclosures or conflicts of interest relevant to this manuscript., (Copyright © 2023. Published by Elsevier B.V.)
- Published
- 2023
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28. A Split Renilla Luciferase Complementation Assay for the Evaluation of Hsp90/Aha1 Complex Disruptors and Their Activity at the Aha1 C-Terminal Domain.
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Keegan BM and Blagg BSJ
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- Luciferases, Renilla genetics, Luciferases, Renilla chemistry, Luciferases, Renilla metabolism, HSP90 Heat-Shock Proteins metabolism, Limonins
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Disruption of interactions between Hsp90 and the cochaperone protein, Aha1, has emerged as a therapeutic strategy to inhibit Aha1-driven cancer metastasis and tau aggregation in models of tauopathy. A combination of split Renilla luciferase assays was developed to screen and quantify the ability of small molecules to disrupt interactions between Hsp90 and both full length Aha1 protein (Aha1-FL) and the Aha1 C-terminal domain (Aha1-CTD). This luminescence-based approach was used to identify withaferin A and gedunin as disruptors of Hsp90/Aha1 interactions and provided insight into the binding regions for gambogic acid and gedunin on the Hsp90 homodimer. All compounds tested that disrupted Hsp90/Aha1-CTD interactions were found to disrupt interactions between Hsp90 and Aha1-FL, suggesting that interactions between Hsp90 and the Aha1-CTD play a key role in the stability of Hsp90/Aha1 complexes.
- Published
- 2023
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29. Progressive motor impairment from "critical" demyelinating lesions of the cervicomedullary junction.
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Jackson-Tarlton CS, Flanagan EP, Messina SA, Barakat B, Ahmad R, Kantarci OH, Weinshenker BG, and Keegan BM
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- Humans, Disease Progression, Disability Evaluation, Neoplasm Recurrence, Local pathology, Spinal Cord diagnostic imaging, Spinal Cord pathology, Brain pathology, Magnetic Resonance Imaging methods, Motor Disorders, Demyelinating Diseases diagnostic imaging, Demyelinating Diseases pathology, Multiple Sclerosis pathology
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Background: Progressive motor impairment anatomically associated with a "critical" lesion has been described in primary demyelinating disease. Most "critical" lesions occur within the spinal cord., Objective: To describe the clinical and radiological features of "critical" lesions of the cervicomedullary junction (CMJ)., Methods: Observational study on people presenting with a CMJ lesion associated with primary demyelinating disease-related progressive motor impairment. Clinical data were extracted by chart review. Brain and spinal cord magnetic resonance images were reviewed to characterize the CMJ lesion and determine additional demyelination burden., Results: Forty-one people were included: 29 (71%) had progression from onset and 12 (29%) had a relapse onset (secondary progressive) course. Most had progressive hemiparesis (21 (51%)) or progressive quadriparesis (15 (37%)) with a median Expanded Disability Status Scale (EDSS) of 5.5 (2.0-8.5) at last follow-up. No "critical" CMJ lesion enhanced; most were bilateral (25 (61%)). Brain magnetic resonance images were otherwise normal in 16 (39%) or with a restricted demyelination burden in 15 (37%). Cervical and thoracic cord MRIs were without additional lesions in 25 (61%) and 22/37 (59%), respectively., Conclusion: CMJ "critical" lesions can correlate with progressive motor impairment even with few or no additional magnetic resonance imaging (MRI) lesions. Lesion location is an important determinant of progressive motor impairment in demyelinating disease.
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- 2023
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30. Diagnosis of coexistent neurodegenerative dementias in multiple sclerosis.
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Londoño DP, Arumaithurai K, Constantopoulos E, Basso MR, Reichard RR, Flanagan EP, and Keegan BM
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Among people with multiple sclerosis, cognitive impairment occurs commonly and is a potent predictor of disability. Some multiple sclerosis patients present with severe cognitive impairment, and distinguishing multiple sclerosis-related cognitive impairment from co-existent progressive neurodegenerative diseases such as Alzheimer disease poses a diagnostic challenge. The use of biomarkers such as PET and CSF proteins may facilitate this distinction. The study was a retrospective, descriptive study on convenience samples of separate cohorts, one of cognitively impaired multiple sclerosis patients evaluated on autopsy to demonstrate coincidence of both multiple sclerosis and neurodegenerative cognitive diseases. The second cohort were cognitively impaired multiple sclerosis patients evaluated by biomarker to investigate possible additional neurodegenerative cognitive disorders contributing to the cognitive impairment. We investigated selected biomarkers among 31 severely impaired patients (biomarker cohort) and 12 severely impaired patients assessed at autopsy and selected 24 (23 biomarker cohort, 1 autopsy cohort) had comprehensive neurocognitive testing. Biomarker cohort investigations included 18F-Fluorodeoxyglucose PET and/or CSF amyloid Aβ1-42, phospho-tau and total tau levels. The autopsy cohort was evaluated with comprehensive neuropathological assessment for aetiology of cognitive impairment. The cohorts shared similar sex, age at multiple sclerosis onset and multiple sclerosis clinical course. The autopsy-cohort patients were older at diagnosis (69.5 versus 57 years, P = 0.006), had longer disease duration [median (range) 20 years (3-59) versus 9 (1-32), P = 0.001] and had more impaired bedside mental status scores at last follow-up [Kokmen median (range) 23 (1-38) versus 31 (9-34) P = 0.01]. Autopsy-cohort patients confirmed, or excluded, coexistent neurogenerative disease by neuropathology gold standard. Most biomarker-cohort patients had informative results evaluating coexistent neurogenerative disease. Biomarkers may be useful in indicating a coexistent neurodegenerative disease earlier, and in life, in patients with multiple sclerosis and significant cognitive impairment., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Guarantors of Brain.)
- Published
- 2022
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31. Synthesis and Evaluation of Small Molecule Disruptors of the Aha1/Hsp90 Complex for the Reduction of Tau Aggregation.
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Keegan BM, Catalfano KC, Banerjee M, and Blagg BSJ
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KU-177 was recently shown to disrupt interactions between Hsp90 and Aha1 in vitro . Subsequent studies in recombinant thioflavin T (ThT) assays demonstrated that KU-177 ablates Aha1-driven enhancement of Hsp90-dependent tau aggregation, which was confirmed by TEM. Using KU-177 as a lead compound, derivatives of KU-177 were synthesized and evaluated for their ability to disrupt Aha1/Hsp90 interactions and inhibit P301L tau aggregation. Preliminary structure-activity relationships were revealed, which led to the identification of a new lead compound that contains a cis -like amide bond. The new lead compounds retain the ability to disrupt Aha1/Hsp90 interactions in SH-SY5Y and SK-BR-3 cells without direct inhibition of Hsp90, providing a new scaffold for subsequent drug discovery efforts., Competing Interests: The authors declare no competing financial interest., (© 2022 American Chemical Society.)
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- 2022
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32. Cerebrospinal fluid evaluation in patients with progressive motor impairment due to critical central nervous system demyelinating lesions.
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Barakat B, Messina S, Nayak S, Kassa R, Sechi E, Flanagan EP, Kantarci O, Weinshenker BG, and Keegan BM
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Background: Elevated intrathecal immunoglobulin G (IgG; oligoclonal bands (OCBs)) or IgG in people with progressive motor impairment due to "critical" demyelinating lesions are of uncertain significance., Objective: Compare clinical/radiological features of people with "critical" demyelinating lesion-induced progressive motor impairment with/without elevated intrathecal IgG synthesis., Methods: A total of 133 people with progressive motor impairment attributable to "critical" demyelinating lesions (corticospinal tract location, consistent with the progressive motor deficit) were compared regarding clinical and radiological presentation with and without ≥2 unique cerebrospinal fluid (CSF) OCB and/or IgG index ≥0.85., Results: Ninety-eight (74%) had CSF-elevated OCB and/or IgG index, higher with increased magnetic resonance imaging-lesion burden. No differences were found with/without CSF abnormalities in sex (46 of 98 female (47%) vs. 22 of 35 (63%), p = 0.11), onset-age (median 49 vs. 50 years, p = 0.5), progression from onset (62 of 98 (63%) vs. 25 of 35 (71%)), progression post-relapse (36 of 98 (37%) vs. 10 of 35 (29%), p = 0.4), and duration between demyelinating disease onset and CSF examination (30 (0-359) vs. 48 (0-323) months p = 0.7). "Critical" lesions were radiologically similar, most commonly cervical spine located (72 of 98 (74%) vs. 19 of 35 (54%), p = 0.18) both with/without CSF abnormalities., Conclusions: People with "critical" demyelinating lesion-induced progressive motor impairment typically have elevated intrathecal IgG (OCB and/or IgG) and similar clinical and radiological presentation regardless of CSF findings, therefore representing valid presentations of progressive demyelinating disease., Competing Interests: Declaration of conflicting interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2022.)
- Published
- 2022
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33. Comparison of MRI Lesion Evolution in Different Central Nervous System Demyelinating Disorders.
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Sechi E, Krecke KN, Messina SA, Buciuc M, Pittock SJ, Chen JJ, Weinshenker BG, Lopez-Chiriboga AS, Lucchinetti CF, Zalewski NL, Tillema JM, Kunchok A, Monaco S, Morris PP, Fryer JP, Nguyen A, Greenwood T, Syc-Mazurek SB, Keegan BM, and Flanagan EP
- Subjects
- Adolescent, Adult, Aged, Brain diagnostic imaging, Child, Child, Preschool, Disease Progression, Female, Humans, Male, Middle Aged, Multiple Sclerosis diagnostic imaging, Multiple Sclerosis pathology, Retrospective Studies, Young Adult, Brain pathology, Demyelinating Diseases diagnostic imaging, Demyelinating Diseases pathology, Magnetic Resonance Imaging
- Abstract
Background and Objective: There are few studies comparing lesion evolution across different CNS demyelinating diseases, yet knowledge of this may be important for diagnosis and understanding differences in disease pathogenesis. We sought to compare MRI T2 lesion evolution in myelin oligodendrocyte glycoprotein immunoglobulin G (IgG)-associated disorder (MOGAD), aquaporin 4 IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG-NMOSD), and multiple sclerosis (MS)., Methods: In this descriptive study, we retrospectively identified Mayo Clinic patients with MOGAD, AQP4-IgG-NMOSD, or MS and (1) brain or myelitis attack; (2) available attack MRI within 6 weeks; and (3) follow-up MRI beyond 6 months without interval relapses in that region. Two neurologists identified the symptomatic or largest T2 lesion for each patient (index lesion). MRIs were then independently reviewed by 2 neuroradiologists blinded to diagnosis to determine resolution of T2 lesions by consensus. The index T2 lesion area was manually outlined acutely and at follow-up to assess variation in size., Results: We included 156 patients (MOGAD, 38; AQP4-IgG-NMOSD, 51; MS, 67) with 172 attacks (brain, 81; myelitis, 91). The age (median [range]) differed between MOGAD (25 [2-74]), AQP4-IgG-NMOSD (53 [10-78]), and MS (37 [16-61]) ( p < 0.01) and female sex predominated in the AQP4-IgG-NMOSD (41/51 [80%]) and MS (51/67 [76%]) groups but not among those with MOGAD (17/38 [45%]). Complete resolution of the index T2 lesion was more frequent in MOGAD (brain, 13/18 [72%]; spine, 22/28 [79%]) than AQP4-IgG-NMOSD (brain, 3/21 [14%]; spine, 0/34 [0%]) and MS (brain, 7/42 [17%]; spine, 0/29 [0%]) ( p < 0.001). Resolution of all T2 lesions occurred most often in MOGAD (brain, 7/18 [39%]; spine, 22/28 [79%]) than AQP4-IgG-NMOSD (brain, 2/21 [10%]; spine, 0/34 [0%]) and MS (brain, 2/42 [5%]; spine, 0/29 [0%]) ( p < 0.01). There was a larger median (range) reduction in T2 lesion area in mm
2 on follow-up axial brain MRI with MOGAD (213 [55-873]) than AQP4-IgG-NMOSD (104 [0.7-597]) ( p = 0.02) and MS (36 [0-506]) ( p < 0.001) and the reductions in size on sagittal spine MRI follow-up in MOGAD (262 [0-888]) and AQP4-IgG-NMOSD (309 [0-1885]) were similar ( p = 0.4) and greater than in MS (23 [0-152]) ( p < 0.001)., Discussion: The MRI T2 lesions in MOGAD resolve completely more often than in AQP4-IgG-NMOSD and MS. This has implications for diagnosis, monitoring disease activity, and clinical trial design, while also providing insight into pathogenesis of CNS demyelinating diseases., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)- Published
- 2021
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34. Inflammatory activity following motor progression due to critical CNS demyelinating lesions.
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Nayak S, Sechi E, Flanagan EP, Messina S, Kassa R, Kantarci O, Weinshenker BG, and Keegan BM
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- Central Nervous System, Disease Progression, Humans, Magnetic Resonance Imaging, Multiple Sclerosis, Multiple Sclerosis, Chronic Progressive complications, Multiple Sclerosis, Chronic Progressive diagnostic imaging
- Abstract
Background: New inflammatory activity is of unclear frequency and clinical significance in progressive multiple sclerosis (MS); it is uncertain in patient cohorts with motor progression due to critical demyelinating lesions., Objectives: The aim of this study is to determine the likelihood of central nervous system (CNS) inflammatory activity, assessed by new clinical relapses or active magnetic resonance imaging (MRI) lesions, following onset of motor progression due to critical demyelinating lesions., Methods: Patients with progressive upper motor neuron impairment for ⩾1 year attributable to critical demyelinating lesions with single CNS lesion (progressive solitary sclerosis (PSS)), 2 to 5 total CNS demyelinating lesions (progressive "pauci-sclerosis" (PPS)), or >5 CNS demyelinating lesions and progressive exclusively unilateral monoparesis or hemiparesis (PUHMS) were identified. Clinical data were reviewed for acute MS relapses, and subsequent MRI was reviewed for active T1-gadolinium-enhancing or T2-demyelinating lesions., Results: None of the 91 patients (22 PSS, 40 PPS, 29 PUHMS) identified experienced clinical relapses over a median clinical follow-up of 93 months (range: 12-518 months). Nine patients (10%) developed active lesions over median 84 months radiologic follow-up (range: 12-518 months). Active lesions occurred in 24% PUHMS, 5% PSS, and 3% PPS cohorts., Conclusion: New inflammatory activity, defined by active lesions and clinical relapses following motor progression in patients with critical demyelinating lesions, is low. Disease-modifying therapies that reduce demyelinating relapses and active MRI lesions are of uncertain benefit in these cohorts.
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- 2021
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35. Assay design and development strategies for finding Hsp90 inhibitors and their role in human diseases.
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Banerjee M, Hatial I, Keegan BM, and Blagg BSJ
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- Biological Assay, Humans, Neoplasms drug therapy, Antineoplastic Agents pharmacology, HSP90 Heat-Shock Proteins antagonists & inhibitors, HSP90 Heat-Shock Proteins drug effects
- Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone that facilitates the maturation of its client proteins including protein kinases, transcription factors, and steroid hormone receptors which are structurally and functionally diverse. These client proteins are involved in various cellular signaling pathways, and Hsp90 is implicated in various human diseases including cancer, inflammation, and diseases associated with protein misfolding; thus making Hsp90 a promising target for drug discovery. Some of its client proteins are well-known cancer targets. Instead of targeting these client proteins individually, however, targeting Hsp90 is more practical for cancer drug development. Efforts have been invested in recognizing potential drugs for clinical use that inhibit Hsp90 activity and result in the prevention of Hsp90 client maturation and dampening of subsequent signaling cascades. Here, we discuss current assays and technologies used to find and characterize Hsp90 inhibitors that include biophysical, biochemical, cell-based assays and computational modeling. This review highlights recent discoveries that N-terminal isoform-selective compounds and inhibitors that target the Hsp90 C-terminus that may offer the potential to overcome some of the detriments observed with pan Hsp90 inhibitors. The tools and assays summarized in this review should be used to develop Hsp90-targeting drugs with high specificity, potency, and drug-like properties that may prove immensely useful in the clinic., Competing Interests: Declaration of Competing Interest Authors report no conflict of interest to declare., (Copyright © 2020. Published by Elsevier Inc.)
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- 2021
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36. Onset of progressive motor impairment in patients with critical central nervous system demyelinating lesions.
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Kassa RM, Sechi E, Flanagan EP, Kaufmann TJ, Kantarci OH, Weinshenker BG, Mandrekar J, Schmalstieg WF, Paz Soldan MM, and Keegan BM
- Subjects
- Adult, Aged, Brain diagnostic imaging, Disease Progression, Humans, Magnetic Resonance Imaging, Middle Aged, Spinal Cord, Young Adult, Motor Disorders, Multiple Sclerosis
- Abstract
Objective: To compare progressive motor impairment onset attributable to a "critical" central nervous system (CNS) demyelinating lesion in patients with highly restricted versus unlimited magnetic resonance imaging (MRI) lesion burden., Methods: We identified 135 patients with progressive motor impairment for ⩾1 year attributable to a "critical" demyelinating lesion with: MRI burden of 1 lesion ("progressive solitary sclerosis"), 2-5 lesions ("progressive paucisclerosis"), or unrestricted (>5) lesions and "progressive unilateral hemiparesis." Neuroradiology review of brain and spinal cord MRI documented unequivocally demyelinating lesions., Results: A total of 33 (24.4%) patients had progressive solitary sclerosis; 56 (41.5%) patients had progressive paucisclerosis; and 46 (34.1%) patients had progressive unilateral hemiparesis. Median age at onset of progressive motor impairment was younger in progressive solitary sclerosis (49 years; range 24-73) and progressive paucisclerosis (50 years; range 30-64) than in progressive unilateral hemiparesis (54 years; range 39-77; p = 0.02 and p = 0.003, respectively). Within progressive unilateral hemiparesis, motor-progression onset was similar between those with 4-10, 11-20, or >20 brain lesions (55, 54, 53 years of age, respectively; p = 0.44)., Conclusion: Motor-progression age is similar, but paradoxically earlier, in cohorts with highly restricted CNS lesion burden than in those with unrestricted lesion burden with progressive unilateral hemiparetic MS. The "critical" demyelinating lesion rather than total brain MRI lesion burden is the major contributor to motor-progression onset in these cohorts.
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- 2021
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37. Critical spinal cord lesions associate with secondary progressive motor impairment in long-standing MS: A population-based case-control study.
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Sechi E, Messina S, Keegan BM, Buciuc M, Pittock SJ, Kantarci OH, Weinshenker BG, and Flanagan EP
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- Case-Control Studies, Disease Progression, Humans, Magnetic Resonance Imaging, Retrospective Studies, Spinal Cord, Motor Disorders, Multiple Sclerosis, Multiple Sclerosis, Chronic Progressive diagnostic imaging, Multiple Sclerosis, Relapsing-Remitting diagnostic imaging
- Abstract
Background: Progressive motor impairment anatomically attributable to prominent, focally atrophic lateral column spinal cord lesions ("critical lesions") can be seen in multiple sclerosis (MS), for example, progressive hemiparetic MS., Objective: The aim of this study was to investigate whether similar spinal cord lesions are more frequent in long-standing MS patients with secondary progressive motor impairment (secondary progressive MS (SPMS)) versus those maintaining a relapsing-remitting course (relapsing-remitting MS (RRMS))., Methods: We retrospectively identified Olmsted County (MN, USA) residents on 31 December 2011 with (1) RRMS or SPMS for ⩾25 years, and (2) available brain and spine magnetic resonance imaging (MRI). A blinded neuroradiologist determined demyelinating lesion burden and presence of potential critical lesions (prominent focally atrophic spinal cord lateral column lesions)., Results: In total, 32 patients were included: RRMS, 18; SPMS, 14. Median (range) disease duration (34 (27-53) vs. 39 (29-47) years) and relapse number (4 (1-10) vs. 3 (1-15)) were similar. In comparison to RRMS, SPMS patients more commonly showed potential critical spinal cord lesions (8/18 (44%) vs. 14/14 (100%)), higher spinal cord (median (range) 4 (1-7) vs. 7.5 (3-12)), and brain infratentorial (median (range) 1 (0-12) vs. 2.5 (1-13)) lesion number; p < 0.05. By multivariate analysis, only the presence of potential critical lesions independently associated with motor progression ( p = 0.02)., Conclusion: Critical spinal cord lesions may be important contributors to motor progression in MS.
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- 2021
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38. Chronic phenmetrazine treatment promotes D 2 dopaminergic and α2-adrenergic receptor desensitization and alters phosphorylation of signaling proteins and local cerebral glucose metabolism in the rat brain.
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Keegan BM, Dreitzler AL, Sexton T, Beveridge TJR, Smith HR, Miller MD, Blough BE, Porrino LJ, Childers SR, and Howlett AC
- Abstract
Phenmetrazine (PHEN) is a putative treatment for cocaine and psychostimulant recidivism; however, neurochemical changes underlying its activity have not been fully elucidated. We sought to characterize brain homeostatic adaptations to chronic PHEN, specifically on functional brain activity (local cerebral glucose utilization), G-Protein Coupled Receptor-stimulated G-protein activation, and phosphorylation of ERK1/2
Thr202/Tyr204 , GSK3βTyr216 , and DARPP-32Thr34 . Male Sprague-Dawley rats were implanted with sub-cutaneous minipumps delivering either saline (vehicle), acute (2-day) or chronic (14-day) low dose (25 mg/kg/day) or high dose (50 mg/kg/day) PHEN. Acute administration of high dose PHEN increased local cerebral glucose utilization measured by 2-[14 C]-deoxyglucose uptake in basal ganglia and motor-related regions of the rat brain. However, chronically treated animals developed tolerance to these effects. To identify the neurochemical changes associated with PHEN's activity, we performed [35 S]GTPγS binding assays on unfixed and immunohistochemistry on fixed coronal brain sections. Chronic PHEN treatment dose-dependently attenuated D2 dopamine and α2 -adrenergic, but not 5-HT1A , receptor-mediated G-protein activation. Two distinct patterns of effects on pERK1/2 and pDARPP-32 were observed: 1) chronic low dose PHEN decreased pERK1/2, and also significantly increased pDARPP-32 levels in some regions; 2) acute and chronic PHEN increased pERK1/2, but chronic high dose PHEN treatment tended to decrease pDARPP-32. Chronic low dose, but not high dose, PHEN significantly reduced pGSK3β levels in several regions. Our study provides definitive evidence that extended length PHEN dosage schedules elicit distinct modes of neuronal acclimatization in cellular signaling. These pharmacodynamic modifications should be considered in drug development for chronic use., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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39. Retinal vasculopathy with cerebral leukoencephalopathy due to TREX-1 mutation: An important mimicker of CNS inflammatory disease.
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Weerasekare J, Kassa R, and Keegan BM
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- Humans, Male, Middle Aged, Mutation, Exodeoxyribonucleases genetics, Leukoencephalopathies diagnostic imaging, Leukoencephalopathies genetics, Phosphoproteins genetics, Retinal Diseases diagnostic imaging, Retinal Diseases genetics
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- 2021
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40. The role and therapeutic potential of Hsp90, Hsp70, and smaller heat shock proteins in peripheral and central neuropathies.
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Chaudhury S, Keegan BM, and Blagg BSJ
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- HSP70 Heat-Shock Proteins, HSP90 Heat-Shock Proteins, Heat-Shock Proteins, Heat-Shock Response, Humans, Heat-Shock Proteins, Small
- Abstract
Heat shock proteins (Hsps) are molecular chaperones that also play important roles in the activation of the heat shock response (HSR). The HSR is an evolutionary conserved and protective mechanism that is used to counter abnormal physiological conditions, stressors, and disease states, such as those exemplified in cancer and/or neurodegeneration. In normal cells, heat shock factor-1 (HSF-1), the transcription factor that regulates the HSR, remains in a dormant multiprotein complex that is formed upon association with chaperones (Hsp90, Hsp70, etc.), co-chaperones, and client proteins. However, under cellular stress, HSF-1 dissociates from Hsp90 and induces the transcriptional upregulation of Hsp70 to afford protection against the encountered cellular stress. As a consequence of both peripheral and central neuropathies, cellular stress occurs and results in the accumulation of unfolded and/or misfolded proteins, which can be counterbalanced by activation of the HSR. Since Hsp90 is the primary regulator of the HSR, modulation of Hsp90 by small molecules represents an attractive therapeutic approach against both peripheral and central neuropathies., (© 2020 Wiley Periodicals LLC.)
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- 2021
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41. Reproductive history and progressive multiple sclerosis risk in women.
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Zeydan B, Atkinson EJ, Weis DM, Smith CY, Gazzuola Rocca L, Rocca WA, Keegan BM, Weinshenker BG, Kantarci K, and Kantarci OH
- Abstract
Being a woman is one of the strongest risk factors for multiple sclerosis. The natural reproductive period from menarche to natural menopause corresponds to the active inflammatory disease period in multiple sclerosis. The fifth decade marks both the peri-menopausal transition in the reproductive aging and a transition from the relapsing-remitting to the progressive phase in multiple sclerosis. A short reproductive period with premature/early menopause and/or low number of pregnancies may be associated with an earlier onset of the progressive multiple sclerosis phase. A cross-sectional study of survey-based reproductive history in a multiple sclerosis clinical series enriched for patients with progressive disease, and a case-control study of multiple sclerosis and age/sex matched controls from a population-based cohort were conducted. Menarche age, number of complete/incomplete pregnancies, menopause type and menopause age were compared between 137 cases and 396 control females. Onset of relapsing-remitting phase of multiple sclerosis, progressive disease onset and reaching severe disability (expanded disability status scale 6) were studied as multiple sclerosis-related outcomes ( n = 233). Menarche age was similar between multiple sclerosis and control females ( P = 0.306). Females with multiple sclerosis had fewer full-term pregnancies than the controls ( P < 0.001). Non-natural menopause was more common in multiple sclerosis (40.7%) than in controls (30.1%) ( P = 0.030). Age at natural menopause was similar between multiple sclerosis (median, interquartile range: 50 years, 48-52) and controls (median, interquartile range: 51 years, 49-53) ( P = 0.476). Nulliparous females had earlier age at progressive multiple sclerosis onset (mean ± standard deviation: 41.9 ± 12.5 years) than females with ≥1 full-term pregnancies (mean ± standard deviation: 47.1 ± 9.7 years) ( P = 0.069) with a pregnancy-dose effect [para 0 (mean ± standard deviation: 41.9 ± 12.5 years), para 1-3 (mean ± standard deviation: 46.4 ± 9.2 years), para ≥4 (mean ± standard deviation: 52.6 ± 12.9 years) ( P = 0.005)]. Menopause age was associated with progressive multiple sclerosis onset age ( R
2 = 0.359, P < 0.001). Duration from onset of relapses to onset of progressive multiple sclerosis was shorter for females with premature/early menopause ( n = 26; mean ± standard deviation: 12.9 ± 9.0 years) than for females with normal menopause age ( n = 39; mean ± standard deviation: 17.8 ± 10.3 years) but was longer than for males (mean ±standard deviation: 10.0 ± 9.4 years) ( P = 0.005). There was a pregnancy-dose effect of age at expanded disability status scale 6 (para 0: 43.0 ± 13.2 years, para 1-3: 51.7 ± 11.3 years, para ≥4: 53.5 ± 4.9 years) ( P = 0.013). Age at menopause was associated with age at expanded disability status scale 6 ( R2 = 0.229, P < 0.003). Premature/early menopause or nulliparity was associated with earlier onset of progressive multiple sclerosis with a 'dose effect' of pregnancies on delaying progressive multiple sclerosis and severe disability. Although causality remains uncertain, our results suggest a beneficial impact of oestrogen in delaying progressive multiple sclerosis. If confirmed in prospective studies, our findings have implications for counselling women with multiple sclerosis about pregnancy, surgical menopause and menopausal hormone therapy., (© The Author(s) (2020). Published by Oxford University Press on behalf of the Guarantors of Brain.)- Published
- 2020
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42. Discovery of Novel Hsp90 C-Terminal Inhibitors Using 3D-Pharmacophores Derived from Molecular Dynamics Simulations.
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Tomašič T, Durcik M, Keegan BM, Skledar DG, Zajec Ž, Blagg BSJ, and Bryant SD
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- Antineoplastic Agents pharmacology, HSP90 Heat-Shock Proteins metabolism, Hep G2 Cells, Humans, MCF-7 Cells, Neoplasm Proteins metabolism, Protein Domains, Quantitative Structure-Activity Relationship, Antineoplastic Agents chemistry, Drug Discovery, HSP90 Heat-Shock Proteins antagonists & inhibitors, HSP90 Heat-Shock Proteins chemistry, Molecular Dynamics Simulation, Neoplasm Proteins antagonists & inhibitors, Neoplasm Proteins chemistry
- Abstract
Hsp90 C-terminal domain (CTD) inhibitors are promising novel agents for cancer treatment, as they do not induce the heat shock response associated with Hsp90 N-terminal inhibitors. One challenge associated with CTD inhibitors is the lack of a co-crystallized complex, requiring the use of predicted allosteric apo pocket, limiting structure-based (SB) design approaches. To address this, a unique approach that enables the derivation and analysis of interactions between ligands and proteins from molecular dynamics (MD) trajectories was used to derive pharmacophore models for virtual screening (VS) and identify suitable binding sites for SB design. Furthermore, ligand-based (LB) pharmacophores were developed using a set of CTD inhibitors to compare VS performance with the MD derived models. Virtual hits identified by VS with both SB and LB models were tested for antiproliferative activity. Compounds 9 and 11 displayed antiproliferative activities in MCF-7 and Hep G2 cancer cell lines. Compound 11 inhibited Hsp90-dependent refolding of denatured luciferase and induced the degradation of Hsp90 clients without the concomitant induction of Hsp70 levels. Furthermore, compound 11 offers a unique scaffold that is promising for the further synthetic optimization and development of molecules needed for the evaluation of the Hsp90 CTD as a target for the development of anticancer drugs.
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- 2020
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43. Association Between Tumor Necrosis Factor Inhibitor Exposure and Inflammatory Central Nervous System Events.
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Kunchok A, Aksamit AJ Jr, Davis JM 3rd, Kantarci OH, Keegan BM, Pittock SJ, Weinshenker BG, and McKeon A
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- Adult, Aged, Case-Control Studies, Demyelinating Autoimmune Diseases, CNS chemically induced, Humans, Middle Aged, Autoimmune Diseases drug therapy, Central Nervous System Diseases chemically induced, Inflammation chemically induced, Tumor Necrosis Factor Inhibitors adverse effects
- Abstract
Importance: Tumor necrosis factor (TNF) inhibitors are common therapies for certain autoimmune diseases, such as rheumatoid arthritis. An association between TNF inhibitor exposure and inflammatory central nervous system (CNS) events has been postulated but is poorly understood., Objective: To evaluate whether TNF inhibitor exposure is associated with inflammatory demyelinating and nondemyelinating CNS events in patients with an indication for TNF inhibitor use and to describe the spectrum of those CNS events., Design, Setting, and Participants: A nested case-control study was conducted using the medical records of patients with autoimmune diseases treated at 3 Mayo Clinic locations (Rochester, Minnesota; Scottsdale, Arizona; and Jacksonville, Florida) between January 1, 2003, and February 20, 2019. Patients were included if their records reported International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, diagnostic codes for US Food and Drug Administration-approved autoimmune disease indication for TNF inhibitor use (ie, rheumatoid arthritis, ankylosing spondylitis, psoriasis and psoriatic arthritis, Crohn disease, and ulcerative colitis) and diagnostic codes for inflammatory CNS events of interest. Patients were matched 1:1 with control participants by year of birth, type of autoimmune disease, and sex., Exposures: TNF inhibitor exposure data were derived from the medical records along with type of TNF inhibitor, cumulative duration of exposure, and time of exposure., Main Outcomes and Measures: The main outcome was either inflammatory demyelinating (multiple sclerosis and other diseases such as optic neuritis) or nondemyelinating (meningitis, meningoencephalitis, encephalitis, neurosarcoidosis, and CNS vasculitis) CNS event. Association with TNF inhibitor was evaluated with conditional logistic regression and adjusted for disease duration to determine the odds ratios (ORs) and 95% CIs. Secondary analyses included stratification of outcome by inflammatory demyelinating and nondemyelinating CNS events and by autoimmune disease (rheumatoid arthritis and non-rheumatoid arthritis)., Results: A total of 212 individuals were included: 106 patients with inflammatory CNS events and 106 control participants without such events. Of this total, 136 were female (64%); the median (interquartile range) age at disease onset for patients was 52 (43-62) years. Exposure to TNF inhibitors occurred in 64 patients (60%) and 42 control participants (40%) and was associated with an increased risk of any inflammatory CNS event (adjusted OR, 3.01; 95% CI, 1.55-5.82; P = .001). These results were similar when the outcome was stratified by demyelinating and nondemyelinating CNS events. Secondary analyses found the association was predominantly observed in patients with rheumatoid arthritis (adjusted OR, 4.82; 95% CI, 1.62-14.36; P = .005)., Conclusions and Relevance: This study found that exposure to TNF inhibitors in patients with autoimmune diseases appeared to be associated with increased risk for inflammatory CNS events. Whether this association represents de novo or exacerbated inflammatory pathways requires further research.
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- 2020
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44. Spinal cord infarction in a patient with multiple sclerosis.
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Abarbanel DN, Zalewski NL, and Keegan BM
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- Female, Humans, Infarction etiology, Middle Aged, Myelitis diagnosis, Spinal Cord Diseases etiology, Infarction diagnosis, Multiple Sclerosis, Relapsing-Remitting complications, Spinal Cord Diseases diagnosis
- Abstract
We describe a 49 year old woman with relapsing-remitting multiple sclerosis (MS) with a suspected severe recurrent attack of myelitis that was ultimately diagnosed as a spinal cord infarction (SCI). This case of SCI in a patient with an established diagnosis of MS highlights the clinical, laboratory, and radiographic characteristics that help distinguish SCI from inflammatory myelitis due to MS., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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45. Unilateral motor progression in MS: Association with a critical corticospinal tract lesion.
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Sechi E, Keegan BM, Kaufmann TJ, Kantarci OH, Weinshenker BG, and Flanagan EP
- Subjects
- Adult, Aged, Disability Evaluation, Disease Progression, Female, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Multiple Sclerosis diagnosis, Sclerosis pathology, Atrophy pathology, Brain pathology, Multiple Sclerosis pathology, Pyramidal Tracts pathology
- Abstract
Objective: Progressive motor impairment anatomically attributable to a single critical demyelinating lesion on eloquent corticospinal tract locations occurs in progressive solitary sclerosis and in some patients with multiple sclerosis (MS) with highly restricted CNS lesion burden (2-5 lesions). We determined whether a similar critical lesion is found in patients with MS with unilateral motor progression and unlimited lesion burden., Methods: In this observational study, we retrospectively identified Mayo Clinic patients (January 1, 1996-December 31, 2017) with an MS diagnosis (2017 McDonald criteria), ≥1 year of exclusively unilateral motor progression, and >5 demyelinating lesions on MRI. A blinded neuroradiologist identified a single critical lesion (last available MRI) based on prominent size, atrophy, and eloquent corticospinal tract location (spinal cord lateral columns, medullary pyramids, cerebral peduncles, internal capsules). We then determined whether the motor impairment was anatomically attributable to the identified lesion., Results: Thirty-eight patients with MS were included: 20 (53%) with primary progressive MS and 18 (47%) with secondary progressive MS. Median age at progression onset was 54 (range 39-73) years. Median Expanded Disability Status Scale score was 5 (range 2.5-7.5) at the last follow-up (median 132.5 months from symptom onset, range 23-390 months). A single critical lesion was identified in 25 of 38 cases (66%): 19 in the cervical cord and 6 in the thoracic cord. In the remaining patients, >1 potential critical lesions were present. The overall probability to detect demyelinating lesions was higher along the corticospinal tract where the motor deficit localized (38 of 38 [100%]) than on the contralateral side (15 of 38 [39%]) ( p < 0.0001)., Conclusions: In patients with MS with unilateral motor progression, the motor deficit may be attributable to a single critical corticospinal tract lesion., (© 2019 American Academy of Neurology.)
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- 2019
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46. An Isoform-Selective PTP1B Inhibitor Derived from Nitrogen-Atom Augmentation of Radicicol.
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Shi T, Wijeratne EMK, Solano C, Ambrose AJ, Ross AB, Norwood C, Orido CK, Grigoryan T, Tillotson J, Kang M, Luo G, Keegan BM, Hu W, Blagg BSJ, Zhang DD, Gunatilaka AAL, and Chapman E
- Subjects
- Animals, Enzyme Inhibitors metabolism, Macrolides metabolism, Mice, Nitrogen metabolism, Protein Binding physiology, Protein Isoforms chemistry, Protein Isoforms metabolism, Protein Structure, Tertiary, Protein Tyrosine Phosphatase, Non-Receptor Type 1 metabolism, Enzyme Inhibitors chemistry, Macrolides chemistry, Nitrogen chemistry, Protein Tyrosine Phosphatase, Non-Receptor Type 1 antagonists & inhibitors, Protein Tyrosine Phosphatase, Non-Receptor Type 1 chemistry
- Abstract
A library of natural products and their derivatives was screened for inhibition of protein tyrosine phosphatase (PTP) 1B, which is a validated drug target for the treatment of obesity and type II diabetes. Of those active in the preliminary assay, the most promising was compound 2 containing a novel pyrrolopyrazoloisoquinolone scaffold derived by treating radicicol ( 1 ) with hydrazine. This nitrogen-atom augmented radicicol derivative was found to be PTP1B selective relative to other highly homologous nonreceptor PTPs. Biochemical evaluation, molecular docking, and mutagenesis revealed 2 to be an allosteric inhibitor of PTP1B with a submicromolar K
i . Cellular analyses using C2C12 myoblasts indicated that 2 restored insulin signaling and increased glucose uptake.- Published
- 2019
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47. Aquaporin-4 and MOG autoantibody discovery in idiopathic transverse myelitis epidemiology.
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Sechi E, Shosha E, Williams JP, Pittock SJ, Weinshenker BG, Keegan BM, Zalewski NL, Lopez-Chiriboga AS, Jitprapaikulsan J, and Flanagan EP
- Subjects
- Adult, Aged, Female, Humans, Immunoglobulin G immunology, Incidence, Male, Middle Aged, Myelitis, Transverse classification, Myelitis, Transverse immunology, Prevalence, Retrospective Studies, Young Adult, Aquaporin 4 immunology, Autoantibodies immunology, Myelin-Oligodendrocyte Glycoprotein immunology, Myelitis, Transverse epidemiology
- Abstract
Objective: Diagnostic criteria from 2002 classify transverse myelitis (TM) as idiopathic or disease associated but predate the discovery of aquaporin-4 (AQP4)-immunoglobulin G (IgG) and myelin oligodendrocyte glycoprotein (MOG)-IgG, which associate with TM. Prior incidence estimates of idiopathic TM (ITM) range from 1 to 6.2 per 1 million. We sought to determine whether the population-based incidence and prevalence of ITM were reduced by testing patients with ITM for AQP4/MOG-IgG and reclassifying seropositive cases as having disease-associated TM., Methods: For this observational study, we retrospectively identified all cases of incident (January 1, 2003-December 31, 2016) and prevalent (December 31, 2016) ITM in Olmsted County (85% white) by using the Rochester Epidemiology Project medical records linkage system. ITM was defined by the 2002 Transverse MyelitisConsortium Working Group diagnostic criteria. Available sera were tested for AQP4-IgG and MOG-IgG., Results: Twenty-four patients (incident 22, prevalent 17) initially met 2002 ITM criteria (longitudinally extensive TM [LETM] 6). Sera were tested for AQP4-IgG in 22 of 24 (92%) and MOG-IgG in 21 of 24 (88%). Three seropositive cases (AQP4-IgG 2, MOG-IgG 1) were identified and reclassified as having disease-associated TM, accounting for 14% of total incident and 12% of total prevalent cases. AQP4-IgG and MOG-IgG seropositive cases represented 50% (3 of 6) of idiopathic LETM. After reclassification of seropositive patients, the final ITM incidence was 8.6 per 1,000,000 and prevalence was 7.9 per 100,000. Three cases of ITM (14%) subsequently fulfilled multiple sclerosis criteria within the study period., Conclusions: The availability of AQP4-IgG and MOG-IgG modestly reduced ITM incidence and prevalence, which remained higher than previously reported in this predominantly white population. Incorporation of these biomarkers into future revisions of TM diagnostic criteria should be considered., (© 2019 American Academy of Neurology.)
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- 2019
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48. Polyneuropathies and chronic inflammatory demyelinating polyradiculoneuropathy in multiple sclerosis.
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Suanprasert N, Taylor BV, Klein CJ, Roforth MM, Karam C, Keegan BM, and Dyck PJB
- Subjects
- Adolescent, Adult, Aged, Cell Adhesion Molecules blood, Child, Female, Humans, Male, Middle Aged, Multiple Sclerosis blood, Multiple Sclerosis pathology, Nerve Fibers metabolism, Nerve Fibers pathology, Nerve Growth Factors blood, Polyradiculoneuropathy, Chronic Inflammatory Demyelinating pathology, Retrospective Studies, Severity of Illness Index, Statistics, Nonparametric, Young Adult, Multiple Sclerosis complications, Polyradiculoneuropathy, Chronic Inflammatory Demyelinating etiology
- Abstract
Background: Polyneuropathies co-occurring with multiple sclerosis (MS) may be underdiagnosed while causing additional disability burden., Objective: To determine polyneuropathy presence and type in MS and compare MS with chronic inflammatory demyelinating polyradiculoneuropathy (MS-CIDP) versus MS with other non-inflammatory polyneuropathies., Methods: Retrospective chart review of Mayo Clinic cases diagnosed with MS and polyneuropathy. Serum from MS-CIDP for pan-IgG autoantibodies to neurofascin-155 were tested when available., Results: From 1980-2013, 133 co-existing MS/ polyneuropathy cases were identified. Twenty-eight MS patients had inflammatory neuropathy (11 CIDP, 5 plexopathy, 2 vasculitis, 4 monoclonal gammopathy-associated, 6 other), 15 inherited neuropathy (8 axonal, 7 demyelinating), 32 diabetic sensorimotor polyneuropathy, and 58 other. 109 had neuropathy beginning simultaneous to or after MS diagnosis (82%). Compared to MS cases with other polyneuropathy subtypes, MS-CIDP cases had absent or reduced ankle reflexes (100 vs. 70%, p = 0.04), earlier age of neuropathy recognition (52 vs. 58 years, p = 0.048), worse impairment (NIS 27 vs. 22 points, p < 0.03), and more acquired demyelinating electrophysiology features (46% vs. 9%, p < 0.003). Of MS-CIDP cases with available serum, 1-in-3 had IgG4 autoantibodies to neurofascin-155., Conclusion: (1) Polyneuropathies occurring in MS contribute to neurological disability. (2) Diagnosing polyneuropathies in people with MS is challenging and, likely, under-diagnosed. Recognition is important as some polyneuropathies (e.g., CIDP) are treatable. (3) The probable over-representation of inflammatory neuropathy (especially CIDP) in MS suggests a shared dysimmune pathogenesis, supported by autoantibodies to neurofascin-155., (Copyright © 2019. Published by Elsevier B.V.)
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- 2019
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49. Late-onset Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like Episodes Presenting With Auditory Agnosia.
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Smith K, Chiu S, Hunt C, Chandregowda A, Babovic-Vuksanovic D, and Keegan BM
- Subjects
- Agnosia complications, Female, Genome, Mitochondrial, Humans, MELAS Syndrome complications, Middle Aged, RNA, Transfer, Leu genetics, Agnosia diagnostic imaging, Agnosia genetics, MELAS Syndrome diagnostic imaging, MELAS Syndrome genetics
- Abstract
Introduction: Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a multisystemic mitochondrial disorder that usually presents in childhood. Patients can have a wide array of neurological symptoms when presenting with stroke-like episodes, and imaging characteristics during the episodes can overlap with different neurological disorders., Case Report: A 61-year-old woman presented with communication difficulties consistent with auditory agnosia and was found to have bitemporal abnormalities on imaging that first raised the concern for herpes simplex virus encephalitis. Further work-up, in conjunction with the patient's past medical and family history, suggested a mitochondrial disorder. Mitochondrial full genome analysis revealed m.3243A>G variant in the MT-TL1 gene, with 6% heteroplasmy in blood leading to a diagnosis of MELAS., Conclusions: MELAS is a disorder with clinical variability. Neuroimaging studies during stroke-like episodes in MELAS can provide significant clues to the underlying disorder. Although patients typically present in childhood, the first stroke-like episode can occur later in life in some patients, potentially related to a lower heteroplasmy level.
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- 2019
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50. Clinical, Radiologic, and Prognostic Features of Myelitis Associated With Myelin Oligodendrocyte Glycoprotein Autoantibody.
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Dubey D, Pittock SJ, Krecke KN, Morris PP, Sechi E, Zalewski NL, Weinshenker BG, Shosha E, Lucchinetti CF, Fryer JP, Lopez-Chiriboga AS, Chen JC, Jitprapaikulsan J, McKeon A, Gadoth A, Keegan BM, Tillema JM, Naddaf E, Patterson MC, Messacar K, Tyler KL, and Flanagan EP
- Subjects
- Adolescent, Adult, Aged, Autoantibodies immunology, Child, Child, Preschool, Encephalomyelitis, Acute Disseminated diagnosis, Encephalomyelitis, Acute Disseminated immunology, Female, Humans, Immunoglobulin G immunology, Male, Middle Aged, Myelitis, Transverse immunology, Neoplasm Recurrence, Local complications, Neuromyelitis Optica immunology, Prognosis, Young Adult, Myelin-Oligodendrocyte Glycoprotein immunology, Myelitis, Transverse diagnosis, Neoplasm Recurrence, Local diagnosis, Neuromyelitis Optica diagnosis
- Abstract
Importance: Recognizing the characteristics of myelin oligodendrocyte glycoprotein autoantibody (MOG-IgG) myelitis is essential for early accurate diagnosis and treatment., Objective: To evaluate the clinical, radiologic, and prognostic features of MOG-IgG myelitis and compare with myelitis with aquaporin-4-IgG (AQP4-IgG) and multiple sclerosis (MS)., Design, Setting, and Participants: We retrospectively identified 199 MOG-IgG-positive Mayo Clinic patients from January 1, 2000, through December 31, 2017, through our neuroimmunology laboratory. Fifty-four patients met inclusion criteria of (1) clinical myelitis; (2) MOG-IgG positivity; and (3) medical records available. We excluded 145 patients without documented myelitis. Myelitis of AQP4-IgG (n = 46) and MS (n = 26) were used for comparison., Main Outcomes and Measures: Outcome variables included modified Rankin score and need for gait aid. A neuroradiologist analyzed spine magnetic resonance imaging of patients with MOG-IgG and control patients blinded to diagnosis., Results: Of 54 included patients with MOG-IgG myelitis, the median age was 25 years (range, 3-73 years) and 24 were women (44%). Isolated transverse myelitis was the initial manifestation in 29 patients (54%), and 10 (19%) were initially diagnosed as having viral/postviral acute flaccid myelitis. Cerebrospinal fluid-elevated oligoclonal bands occurred in 1 of 38 (3%). At final follow-up (median, 24 months; range, 2-120 months), 32 patients (59%) had developed 1 or more relapses of optic neuritis (n = 31); transverse myelitis (n = 7); or acute disseminated encephalomyelitis (n = 1). Clinical features favoring MOG-IgG myelitis vs AQP4-IgG or MS myelitis included prodromal symptoms and concurrent acute disseminated encephalomyelitis. Magnetic resonance imaging features favoring MOG-IgG over AQP4-IgG or MS myelitis were T2-signal abnormality confined to gray matter (sagittal line and axial H sign) and lack of enhancement. Longitudinally extensive T2 lesions were of similar frequency in MOG-IgG and AQP4-IgG myelitis (37 of 47 [79%] vs 28 of 34 [82%]; P = .52) but not found in MS. Multiple spinal cord lesions and conus involvement were more frequent with MOG-IgG than AQP4-IgG but not different from MS. Wheelchair dependence at myelitis nadir occurred in one-third of patients with MOG-IgG and AQP4-IgG but never with MS, although patients with MOG-IgG myelitis recovered better than those with AQP4-IgG., Conclusions and Relevance: Myelitis is an early manifestation of MOG-IgG-related disease and may have a clinical phenotype of acute flaccid myelitis. We identified a variety of clinical and magnetic resonance imaging features that may help clinicians identify those at risk in whom MOG-IgG should be tested.
- Published
- 2019
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