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Dive into the research topics where John C. Morgan is active.

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Featured researches published by John C. Morgan.


Movement Disorders | 2008

Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS): Scale Presentation and Clinimetric Testing Results

Christopher G. Goetz; Barbara C. Tilley; Stephanie R. Shaftman; Glenn T. Stebbins; Stanley Fahn; Pablo Martinez-Martin; Werner Poewe; Cristina Sampaio; Matthew B. Stern; Richard Dodel; Bruno Dubois; Robert G. Holloway; Joseph Jankovic; Jaime Kulisevsky; Anthony E. Lang; Andrew J. Lees; Sue Leurgans; Peter A. LeWitt; David L. Nyenhuis; C. Warren Olanow; Olivier Rascol; Anette Schrag; Jeanne A. Teresi; Jacobus J. van Hilten; Nancy R. LaPelle; Pinky Agarwal; Saima Athar; Yvette Bordelan; Helen Bronte-Stewart; Richard Camicioli

We present a clinimetric assessment of the Movement Disorder Society (MDS)‐sponsored revision of the Unified Parkinsons Disease Rating Scale (MDS‐UPDRS). The MDS‐UDPRS Task Force revised and expanded the UPDRS using recommendations from a published critique. The MDS‐UPDRS has four parts, namely, I: Non‐motor Experiences of Daily Living; II: Motor Experiences of Daily Living; III: Motor Examination; IV: Motor Complications. Twenty questions are completed by the patient/caregiver. Item‐specific instructions and an appendix of complementary additional scales are provided. Movement disorder specialists and study coordinators administered the UPDRS (55 items) and MDS‐UPDRS (65 items) to 877 English speaking (78% non‐Latino Caucasian) patients with Parkinsons disease from 39 sites. We compared the two scales using correlative techniques and factor analysis. The MDS‐UPDRS showed high internal consistency (Cronbachs alpha = 0.79–0.93 across parts) and correlated with the original UPDRS (ρ = 0.96). MDS‐UPDRS across‐part correlations ranged from 0.22 to 0.66. Reliable factor structures for each part were obtained (comparative fit index > 0.90 for each part), which support the use of sum scores for each part in preference to a total score of all parts. The combined clinimetric results of this study support the validity of the MDS‐UPDRS for rating PD.


Neurology | 2010

Practice Parameter: Treatment of nonmotor symptoms of Parkinson disease Report of the Quality Standards Subcommittee of the American Academy of Neurology

Theresa A. Zesiewicz; Kelly L. Sullivan; Isabelle Arnulf; Kallol Ray Chaudhuri; John C. Morgan; Gary S. Gronseth; Janis Miyasaki; Donald J. Iverson; William J. Weiner

Objective: Nonmotor symptoms (sleep dysfunction, sensory symptoms, autonomic dysfunction, mood disorders, and cognitive abnormalities) in Parkinson disease (PD) are a major cause of morbidity, yet are often underrecognized. This evidence-based practice parameter evaluates treatment options for the nonmotor symptoms of PD. Articles pertaining to cognitive and mood dysfunction in PD, as well as treatment of sialorrhea with botulinum toxin, were previously reviewed as part of American Academy of Neurology practice parameters and were not included here. Methods: A literature search of MEDLINE, EMBASE, and Science Citation Index was performed to identify clinical trials in patients with nonmotor symptoms of PD published between 1966 and August 2008. Articles were classified according to a 4-tiered level of evidence scheme and recommendations were based on the level of evidence. Results and Recommendations: Sildenafil citrate (50 mg) may be considered to treat erectile dysfunction in patients with Parkinson disease (PD) (Level C). Macrogol (polyethylene glycol) may be considered to treat constipation in patients with PD (Level C). The use of levodopa/carbidopa probably decreases the frequency of spontaneous nighttime leg movements, and should be considered to treat periodic limb movements of sleep in patients with PD (Level B). There is insufficient evidence to support or refute specific treatments for urinary incontinence, orthostatic hypotension, and anxiety (Level U). Future research should include concerted and interdisciplinary efforts toward finding treatments for nonmotor symptoms of PD.


JAMA | 2015

Effect of creatine monohydrate on clinical progression in patients with Parkinson disease: a randomized clinical trial.

Karl Kieburtz; Barbara C. Tilley; Jordan J. Elm; Debra Babcock; Robert A. Hauser; G. Webster Ross; Alicia H. Augustine; Erika U. Augustine; Michael J. Aminoff; Ivan G. Bodis-Wollner; James T. Boyd; Franca Cambi; Kelvin L. Chou; Chadwick W. Christine; Michelle Cines; Nabila Dahodwala; Lorelei Derwent; Richard B. Dewey; Katherine Hawthorne; David J. Houghton; Cornelia Kamp; Maureen A. Leehey; Mark F. Lew; Grace S. Liang; Sheng Luo; Zoltan Mari; John C. Morgan; Sotirios A. Parashos; Adriana Pérez; Helen Petrovitch

IMPORTANCE There are no treatments available to slow or prevent the progression of Parkinson disease, despite its global prevalence and significant health care burden. The National Institute of Neurological Disorders and Stroke Exploratory Trials in Parkinson Disease program was established to promote discovery of potential therapies. OBJECTIVE To determine whether creatine monohydrate was more effective than placebo in slowing long-term clinical decline in participants with Parkinson disease. DESIGN, SETTING, AND PATIENTS The Long-term Study 1, a multicenter, double-blind, parallel-group, placebo-controlled, 1:1 randomized efficacy trial. Participants were recruited from 45 investigative sites in the United States and Canada and included 1741 men and women with early (within 5 years of diagnosis) and treated (receiving dopaminergic therapy) Parkinson disease. Participants were enrolled from March 2007 to May 2010 and followed up until September 2013. INTERVENTIONS Participants were randomized to placebo or creatine (10 g/d) monohydrate for a minimum of 5 years (maximum follow-up, 8 years). MAIN OUTCOMES AND MEASURES The primary outcome measure was a difference in clinical decline from baseline to 5-year follow-up, compared between the 2 treatment groups using a global statistical test. Clinical status was defined by 5 outcome measures: Modified Rankin Scale, Symbol Digit Modalities Test, PDQ-39 Summary Index, Schwab and England Activities of Daily Living scale, and ambulatory capacity. All outcomes were coded such that higher scores indicated worse outcomes and were analyzed by a global statistical test. Higher summed ranks (range, 5-4775) indicate worse outcomes. RESULTS The trial was terminated early for futility based on results of a planned interim analysis of participants enrolled at least 5 years prior to the date of the analysis (n = 955). The median follow-up time was 4 years. Of the 955 participants, the mean of the summed ranks for placebo was 2360 (95% CI, 2249-2470) and for creatine was 2414 (95% CI, 2304-2524). The global statistical test yielded t1865.8 = -0.75 (2-sided P = .45). There were no detectable differences (P < .01 to partially adjust for multiple comparisons) in adverse and serious adverse events by body system. CONCLUSIONS AND RELEVANCE Among patients with early and treated Parkinson disease, treatment with creatine monohydrate for at least 5 years, compared with placebo did not improve clinical outcomes. These findings do not support the use of creatine monohydrate in patients with Parkinson disease. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00449865.


Lancet Neurology | 2005

Drug-induced tremors

John C. Morgan; Kapil D. Sethi

Tremor is a common complaint for many patients. Caffeine and beta-adrenergic agonists are well-recognised drugs that cause or exacerbate tremors. Other tremorogenic drugs, such as selective serotonin reuptake inhibitors and tricyclic antidepressants, are less well recognised. Recognition of the drugs that can cause or exacerbate tremors can help prompt diagnosis, avoids unnecessary tests, and allows clinicians to quickly take corrective action (usually by discontinuing the tremor-inducing drugs). The aim of this review is to provide clinicians with current information on drugs that are associated with tremor and the correct treatment of these drug-induced tremors.


Parkinsonism & Related Disorders | 2013

Nintendo Wii rehabilitation (“Wii-hab”) provides benefits in Parkinson's disease

Nathan B. Herz; Shyamal H. Mehta; Kapil D. Sethi; Paula Jackson; Patricia Hall; John C. Morgan

Parkinsons disease (PD) impairs both activities of daily living (ADLs) and motor function and has adverse effects on mood in many patients. While dopaminergic medications are quite helpful for motor and ADLs impairments in PD, complementary therapies are also important in helping patients achieve maximum benefits and quality of life. We hypothesized that the Nintendo Wii (Wii) is a useful tool in improving motor and non-motor aspects in patients with PD, given its ability to drive functional movements and interactive nature. We enrolled twenty subjects with early to mid-stage PD in an open-label within-subjects study design where each subject was evaluated at baseline and then re-evaluated after playing the Wii three times per week for four weeks. Subjects were then re-evaluated one month later after not playing the Wii for a month to see if effects carried over. Subjects demonstrated significant improvements in the primary outcome measure (Nottingham Extended Activities of Daily Living Test (NEADL)), quality of life (PDQ-39) and motor function (UPDRS), and a trend toward improved mood (HAM-D) after four weeks of Wii therapy. Follow-up assessments one month later showed continued improvement for quality of life and UPDRS scores. The results demonstrate that Wii therapy provides short-term motor, non-motor, and quality of life benefits in PD. Further studies are needed to determine if there are long-term benefits of Wii therapy in PD.


Cns Spectrums | 2008

Sleep disorders associated with Parkinson's disease: Role of dopamine, epidemiology, and clinical scales of assessment

Shyamal H. Mehta; John C. Morgan; Kapil D. Sethi

Sleep dysfunction is common among patients with Parkinsons disease and occurs in approximately two thirds of patients. The problems range from nocturnal issues such as difficulty with sleep initiation, sleep fragmentation, disturbance of circadian rhythm, and rapid eye movement sleep behavior disorder, to daytime problems such as excessive daytime sleepiness. Frequent nighttime awakening and sleep disruption are the most common sleep problems in Parkinsons disease. Dopamine plays an important role in maintaining wakefulness. To improve sleep in Parkinsons disease, it is important to achieve the critical balance of adequate dopaminergic therapy and control of symptoms. Increased dopaminergic agents can cause dyskinesias and painful dystonia, and undertreatment can cause nighttime akinesia, rigidity, and worse quality of sleep. Other nondopaminergic drugs commonly used in Parkinsons disease can also affect sleep. In patients with advanced Parkinsons disease, deep brain stimulation of the subthalamic nucleus has a favorable impact on sleep quality and sleep architecture.


The Journal of Neuroscience | 2016

Distinct Nrf2 Signaling Mechanisms of Fumaric Acid Esters and Their Role in Neuroprotection against 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine-Induced Experimental Parkinson's-Like Disease.

Manuj Ahuja; Navneet Ammal Kaidery; Lichuan Yang; Noel Y. Calingasan; Natalya A. Smirnova; Arsen Gaisin; Irina N. Gaisina; Irina G. Gazaryan; D. M. Hushpulian; Ismail Kaddour-Djebbar; Wendy B. Bollag; John C. Morgan; Rajiv R. Ratan; Anatoly A. Starkov; M. Flint Beal; Bobby Thomas

A promising approach to neurotherapeutics involves activating the nuclear-factor-E2-related factor 2 (Nrf2)/antioxidant response element signaling, which regulates expression of antioxidant, anti-inflammatory, and cytoprotective genes. Tecfidera, a putative Nrf2 activator, is an oral formulation of dimethylfumarate (DMF) used to treat multiple sclerosis. We compared the effects of DMF and its bioactive metabolite monomethylfumarate (MMF) on Nrf2 signaling and their ability to block 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced experimental Parkinsons disease (PD). We show that in vitro DMF and MMF activate the Nrf2 pathway via S-alkylation of the Nrf2 inhibitor Keap1 and by causing nuclear exit of the Nrf2 repressor Bach1. Nrf2 activation by DMF but not MMF was associated with depletion of glutathione, decreased cell viability, and inhibition of mitochondrial oxygen consumption and glycolysis rates in a dose-dependent manner, whereas MMF increased these activities in vitro. However, both DMF and MMF upregulated mitochondrial biogenesis in vitro in an Nrf2-dependent manner. Despite the in vitro differences, both DMF and MMF exerted similar neuroprotective effects and blocked MPTP neurotoxicity in wild-type but not in Nrf2 null mice. Our data suggest that DMF and MMF exhibit neuroprotective effects against MPTP neurotoxicity because of their distinct Nrf2-mediated antioxidant, anti-inflammatory, and mitochondrial functional/biogenetic effects, but MMF does so without depleting glutathione and inhibiting mitochondrial and glycolytic functions. Given that oxidative damage, neuroinflammation, and mitochondrial dysfunction are all implicated in PD pathogenesis, our results provide preclinical evidence for the development of MMF rather than DMF as a novel PD therapeutic. SIGNIFICANCE STATEMENT Almost two centuries since its first description by James Parkinson, Parkinsons disease (PD) remains an incurable disease with limited symptomatic treatment. The current study provides preclinical evidence that a Food and Drug Administration-approved drug, dimethylfumarate (DMF), and its metabolite monomethylfumarate (MMF) can block nigrostriatal dopaminergic neurodegeneration in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of PD. We elucidated mechanisms by which DMF and its active metabolite MMF activates the redox-sensitive transcription factor nuclear-factor-E2-related factor 2 (Nrf2) to upregulate antioxidant, anti-inflammatory, mitochondrial biosynthetic and cytoprotective genes to render neuroprotection via distinct S-alkylating properties and depletion of glutathione. Our data suggest that targeting Nrf2-mediated gene transcription using MMF rather than DMF is a promising approach to block oxidative stress, neuroinflammation, and mitochondrial dysfunction for therapeutic intervention in PD while minimizing side effects.


Neurologic Clinics | 2004

Drug-induced movement disorders

Shyamal H. Mehta; John C. Morgan; Kapil D. Sethi

Movement disorders are frequently a result of prescription drugs or of illicit drug use. This article focuses on prescribed drugs but briefly mentions drugs of abuse. The main emphasis is on movement disorders caused by dopamine receptor-blocking agents. However, movement disorders caused by other drugs are also briefly discussed.


Movement Disorders | 2006

Self-stimulatory behavior associated with deep brain stimulation in Parkinson's disease

John C. Morgan; Caroline J. diDonato; Sanjay S. Iyer; Patrick D. Jenkins; Joseph R. Smith; Kapil D. Sethi

1. Clark LN, Nicolai A, Afridi S, et al. Pilot association study of the beta-glucocerebrosidase N370S allele and Parkinson’s disease in subjects of Jewish ethnicity. Mov Disord 2005;20:100–103. 2. Sato C, Morgan A, Lang AE, et al. Analysis of the glucocerebrosidase gene in Parkinson’s disease. Mov Disord 2005;20:367–370. 3. Neudorfer O, Giladi N, Elstein D, et al. Occurrence of Parkinson’s syndrome in type I Gaucher disease. Q J Med 1996;89:691–694. 4. Tayebi N, Walker J, Stubblefield B, et al. Gaucher disease with parkinsonian manifestations: does glucocerebrosidase deficiency contribute to a vulnerability to parkinsonism? Mol Genet Metab 2003;79:104–109. 5. Wong K, Sidransky E, Verma A, et al. Neuropathology provides clues to the pathophysiology of Gaucher disease. Mol Genet Metab 2004;82:192–207. 6. Goker-Alpan O, Schiffmann R, LaMarca ME, Nussbaum RL, McInerney-Leo A, Sidransky E. Parkinsonism among Gaucher disease carriers. J Med Genet 2004;41:937–940. 7. Lwin A, Orvisky E, Goker-Alpan O, LaMarca ME, Sidransky E. Glucocerebrosidase mutations in subjects with parkinsonism. Mol Genet Metab 2004;81:70–73. 8. Eblan MJ, Walker JM, Sidransky E. The glucocerebrosidase gene and Parkinson’s disease in Ashkenazi Jews. N Engl J Med 2005; 352:728–731; author reply 728–731. 9. Aharon-Peretz J, Rosenbaum H, Gershoni-Baruch R. Mutations in the glucocerebrosidase gene and Parkinson’s disease in Ashkenazi Jews. N Engl J Med 2004;351:1972–1977. 10. Koprivica V, Stone DL, Park JK, et al. Analysis and classification of 304 mutant alleles in patients with type 1 and type 3 Gaucher disease. Am J Hum Genet 2000;66:1777–1786. 11. Dvir H, Harel M, McCarthy AA, et al. X-ray structure of human acid-beta-glucosidase, the defective enzyme in Gaucher disease. EMBO Rep 2003;4:704–709.


Clinical Neuropharmacology | 2007

Tegaserod in constipation associated with Parkinson disease.

John C. Morgan; Kapil D. Sethi

Impaired gastrointestinal motility and constipation are common problems in Parkinson disease (PD). Many patients with PD continue to experience constipation, despite multiple interventions (dietary modification, bulk-forming agents, stool softeners, and laxatives). Tegaserod is a 5-hydroxytryptamine type 4 agonist that stimulates gastrointestinal motility and is approved for the treatment of chronic idiopathic constipation. We report our experience with tegaserod in 5 patients with PD-associated constipation. Tegaserod was well tolerated and improved both bowel movement frequency and stool consistency in most of our patients. Further trials with tegaserod are warranted in PD-associated constipation.

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Kapil D. Sethi

Georgia Regents University

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Raymond Chong

Georgia Regents University

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Zoltan Mari

Johns Hopkins University

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Julie A. Kurek

Georgia Regents University

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Maureen A. Leehey

University of Colorado Denver

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Robert A. Hauser

University of South Florida

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Sanjay S. Iyer

Georgia Regents University

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