10 results on '"Matthew W. Morris"'
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2. Anatomical Registration of Implanted Sensors Improves Accuracy of Trunk Tilt Estimates with a Networked Neuroprosthesis
- Author
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Matthew W. Morrison, Michael E. Miller, Lisa M. Lombardo, Ronald J. Triolo, and Musa L. Audu
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trunk control ,sensor reorientation ,networked neuroprosthesis ,spinal cord injury ,musculoskeletal ,Chemical technology ,TP1-1185 - Abstract
For individuals with spinal cord injuries (SCIs) above the midthoracic level, a common complication is the partial or complete loss of trunk stability in the seated position. Functional neuromuscular stimulation (FNS) can restore seated posture and other motor functions after paralysis by applying small electrical currents to the peripheral motor nerves. In particular, the Networked Neuroprosthesis (NNP) is a fully implanted, modular FNS system that is also capable of capturing information from embedded accelerometers for measuring trunk tilt for feedback control of stimulation. The NNP modules containing the accelerometers are located in the body based on surgical constraints. As such, their exact orientations are generally unknown and cannot be easily assessed. In this study, a method for estimating trunk tilt that employed the Gram–Schmidt method to reorient acceleration signals to the anatomical axes of the body was developed and deployed in individuals with SCI using the implanted NNP system. An anatomically realistic model of a human trunk and five accelerometer sensors was developed to verify the accuracy of the reorientation algorithm. Correlation coefficients and root mean square errors (RMSEs) were calculated to compare target trunk tilt estimates and tilt estimates derived from simulated accelerometer signals under a variety of conditions. Simulated trunk tilt estimates with correlation coefficients above 0.92 and RMSEs below 5° were achieved. The algorithm was then applied to accelerometer signals from implanted sensors installed in three NNP recipients. Error analysis was performed by comparing the correlation coefficients and RMSEs derived from trunk tilt estimates calculated from implanted sensor signals to those calculated via motion capture data, which served as the gold standard. NNP-derived trunk tilt estimates exhibited correlation coefficients between 0.80 and 0.95 and RMSEs below 13° for both pitch and roll in most cases. These findings suggest that the algorithm is effective at estimating trunk tilt with the implanted sensors of the NNP system, which implies that the method may be appropriate for extracting feedback signals for control systems for seated stability with NNP technology for individuals who have reduced control of their trunk due to paralysis.
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- 2024
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3. Neuroglobin protects PC12 cells against β-amyloid-induced cell injury
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Richard C. Li, Farzan Pouranfar, Yang Wang, David Gozal, Matthew W. Morris, and Seung Kwan Lee
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Aging ,Amyloid ,Amyloid beta ,Neuroglobin ,Apoptosis ,Nerve Tissue Proteins ,medicine.disease_cause ,PC12 Cells ,Neuroprotection ,Article ,medicine ,Animals ,Neurons ,chemistry.chemical_classification ,Reactive oxygen species ,Amyloid beta-Peptides ,biology ,General Neuroscience ,Peptide Fragments ,Globins ,Rats ,Cell biology ,Oxidative Stress ,Neuroprotective Agents ,chemistry ,biology.protein ,Neurology (clinical) ,Geriatrics and Gerontology ,Reactive Oxygen Species ,Oxidative stress ,Intracellular ,Developmental Biology - Abstract
Excessive accumulation of amyloid beta (Abeta) has been proposed as a pivotal event in the pathogenesis of Alzheimer's disease. Possible mechanisms underlying Abeta-induced neuronal cytotoxicity include excess production of reactive oxidative species (ROS) and apoptosis. Neuroglobin (Ngb), a newly discovered globin in vertebrates that exhibits neuroprotective functions, may have a potential role in scavenging ROS. To examine the potential protective role of Ngb in Abeta-induced cytotoxicity, PC12 cells were treated with Abeta (1-42 fragment) for 24h. Abeta treatments increased ROS production in PC12 cells. Overexpression of Ngb but not Ngb mutant in the PC12 cells significantly attenuated Abeta-induced ROS production and lipids peroxidation. Furthermore, overexpression of Ngb also attenuated Abeta-induced mitochondrial dysfunction and apoptosis, and promoted cell survival in PC12 cells. Therefore, Ngb may act as an intracellular ROS scavenger, and such antioxidant properties may play a protective role against Abeta-induced cell injury.
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- 2008
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4. Efficacy of olanzapine and haloperidol in an animal model of mania
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M. Adnan El-Masri, Robert S. Levy, Matthew W. Morris, Xiao-Ping Li, Sarah Decker, Mary O. Huff, and Rif S. El-Mallakh
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Male ,Olanzapine ,Bipolar Disorder ,medicine.medical_treatment ,Haloperidol Decanoate ,Pharmacology ,Open field ,Ouabain ,Rats, Sprague-Dawley ,Benzodiazepines ,medicine ,Haloperidol ,Animals ,Drug Interactions ,Enzyme Inhibitors ,Antipsychotic ,Biological Psychiatry ,Analysis of Variance ,Behavior, Animal ,business.industry ,Dopamine antagonist ,Rats ,Disease Models, Animal ,Exploratory Behavior ,Drug Evaluation ,medicine.symptom ,business ,Mania ,Antipsychotic Agents ,medicine.drug - Abstract
Purpose Intracerebroventricular (ICV) administration of ouabain, a potent sodium pump inhibitor, has been used to model mania. Antipsychotic agents have demonstrated efficacy in the management of acute mania. This study was undertaken to determine the prophylactic efficacy of olanzapine and haloperidol in the ouabain mania model. Methods Male Sprague–Dawley rats (4–8/group) were treated with two haloperidol decanoate intramuscular shots one week apart (21 mg/kg) or twice daily olanzapine intraperitoneal injections at low dose (1 mg/kg/day) or high dose (6 mg/kg/day) for 7 days prior to ICV administration of ouabain. Open field locomotion was quantified at baseline and after ouabain administration. Results Ouabain caused a significant increase in open field locomotion (253.7 ± SEM 55.12 vs control 53.1 ± 12.13 squares traversed in 30 min in the olanzapine experiments, P
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- 2006
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5. Neuroglobin protects PC12 cells against oxidative stress
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Seung Kwan Lee, Farzan Pouranfar, Yang Wang, Richard C. Li, Matthew W. Morris, and David Gozal
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Neuroglobin ,Nerve Tissue Proteins ,medicine.disease_cause ,Transfection ,Neuroprotection ,PC12 Cells ,Article ,Lipid peroxidation ,chemistry.chemical_compound ,medicine ,Animals ,Molecular Biology ,Reactive nitrogen species ,chemistry.chemical_classification ,Neurons ,Reactive oxygen species ,biology ,Cell Death ,General Neuroscience ,Wild type ,Hydrogen Peroxide ,Molecular biology ,Cell biology ,Globins ,Rats ,Oxidative Stress ,Neuroprotective Agents ,chemistry ,Catalase ,biology.protein ,Neurology (clinical) ,Reactive Oxygen Species ,Oxidative stress ,Developmental Biology - Abstract
Neuroglobin (Ngb) is a newly discovered globin in the vertebrate brain that exhibits neuroprotection against hypoxic/ischemic injury. Hypoxic/ischemic brain injury is associated with accumulation of reactive oxygen species (ROS) and/or reactive nitrogen species (RNS), and antioxidants or ROS scavengers promote cell survival. Therefore, Ngb may serve as a scavenger of toxic reactive species, such as hydrogen peroxide. To examine the anti-oxidative role of neuroglobin, PC12 cells were transfected with wild type and mutant (H64 V/H96A) Ngb for 48 h and then treated with H2O2 (0.1, 0.2 and 0.4 mM) for 6 h. Ngb siRNA decreased the H2O2-induced Ngb expression and exacerbated H2O2-induced cell injury. Transient transfection of Ngb induced dose-dependent increases in Ngb protein expression and did not alter SOD, GPX, and catalase activities. Overexpression of wild type Ngb, but not of mutant Ngb, significantly attenuated H2O2-induced ROS/RNS accumulation and lipid peroxidation, decreased H2O2-induced mitochondrial dysfunction and apoptosis, and promoted overall cell survival. Thus, Ngb plays a protective role against oxidative stress, which appears to be primarily mediated by intrinsic Ngb antioxidant properties.
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- 2007
6. Trends of drug resistant Mycobacterium tuberculosis in a tertiary tuberculosis center in Iran
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Mehdi S, Mirsaeidi, Payam, Tabarsi, Parissa, Farnia, Golnaz, Ebrahimi, Matthew W, Morris, Mohammad R, Masjedi, Ali A, Velayati, and Davood, Mansouri
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Adult ,Aged, 80 and over ,Male ,Adolescent ,Academies and Institutes ,Antitubercular Agents ,Microbial Sensitivity Tests ,Mycobacterium tuberculosis ,Iran ,Middle Aged ,Cross-Sectional Studies ,Population Surveillance ,Tuberculosis, Multidrug-Resistant ,Prevalence ,Humans ,Female ,Aged - Abstract
To determine the drug resistance pattern to first line antituberculous drugs in National Research Institute of Tuberculosis and Lung Disease and to compare resistant rates with previous studies.An anterograde cross-sectional study was performed. The study includes all adults with documented pulmonary tuberculosis (TB) that were hospitalized in National Research Institute of Tuberculosis and Lung Disease in Tehran, from June 2003 to September 2004. Demographic characteristic, TB categories, and drug susceptibility test results were recorded. Two previous studies regarding drug susceptibility in Iran were selected as historical controls.One hundred and ninety-six new cases and 68 previously treated patients were enrolled in the study. The strains of 61% of new patients and 21% of previously treated patients were fully sensitive to all drugs. The most common resistance was streptomycin (27%) followed by isoniazid (23%) in new cases. Multiple drug resistant strains were noted in 2.6% (95% CI 0.8% to 5.8%) of new cases versus 56% (95% CI 43% to 68%) in previously treated group. The frequency of primary drug resistance to isoniazid was 9.8%-15% or streptomycin 9.8%-13% in the previous studies (p0.00001).While these rates may not reflect the true prevalence of drug resistance on a national scale, it does partially demonstrate some defects in the existing tuberculosis control program. The significant increase of isoniazid and streptomycin resistance in the last few years would present a serious challenge to effective management of TB.
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- 2007
7. Clinical Neuroradiology: A Case-Based Approach
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Matthew W. Morris
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medicine.medical_specialty ,Case based approach ,business.industry ,Medicine ,Radiology, Nuclear Medicine and imaging ,Medical physics ,General Medicine ,business ,Neuroradiology - Published
- 2010
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8. Nuclear Medicine Board Review: Questions and Answers for Self-Assessment, 3rd ed
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Matthew W. Morris
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Questions and answers ,Self-assessment ,medicine.medical_specialty ,Medical education ,business.industry ,Alternative medicine ,medicine ,Physiology ,Radiology, Nuclear Medicine and imaging ,General Medicine ,business - Published
- 2013
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9. Case-Based Nuclear Medicine, 2nd ed
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Matthew W. Morris
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medicine.medical_specialty ,business.industry ,Family medicine ,medicine ,Radiology, Nuclear Medicine and imaging ,General Medicine ,business - Published
- 2013
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10. Thoracic Imaging: Case Review Series, 2nd ed
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Matthew W. Morris
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medicine.medical_specialty ,Thoracic imaging ,Series (mathematics) ,business.industry ,medicine ,Radiology, Nuclear Medicine and imaging ,General Medicine ,Radiology ,business ,Case review - Published
- 2012
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- View/download PDF
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