95 results on '"Thurman M"'
Search Results
52. 34. Phi C31 Integrase System Enhances Dystrophin Gene Expression in Skeletal Muscle of Mouse Models for Duchenne Muscular Dystrophy
- Author
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Eric C. Olivares, Carmen Bertoni, Thurman M. Wheeler, Thomas A. Rando, Sohail Jarrahian, Yining Li, and Michele P. Calos
- Subjects
Pharmacology ,biology ,Duchenne muscular dystrophy ,Skeletal muscle ,musculoskeletal system ,medicine.disease ,Dystrophin gene ,Cell biology ,Integrase ,medicine.anatomical_structure ,Drug Discovery ,Utrophin ,Genetics ,biology.protein ,medicine ,Molecular Medicine ,ITGA7 ,Molecular Biology - Published
- 2006
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53. Progressive myopathy in an inducible mouse model of oculopharyngeal muscular dystrophy
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Mankodi, Ami, primary, Wheeler, Thurman M., additional, Shetty, Reena, additional, Salceies, Kelly M., additional, Becher, Mark W., additional, and Thornton, Charles A., additional
- Published
- 2012
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54. A Resident, Rural Telepsychiatry Service: Training and Improving Care for Rural Populations
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Shore, J. H., primary, Thurman, M. T., additional, Fujinami, L., additional, Brooks, E., additional, and Nagamoto, H., additional
- Published
- 2011
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55. United States Forward Military Presence in Europe...A Strategic Necessity
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ARMY WAR COLL CARLISLE BARRACKS PA, Pittman, Thurman M., ARMY WAR COLL CARLISLE BARRACKS PA, and Pittman, Thurman M.
- Abstract
The United States has over 100,000 men and women of its armed forces currently stationed in or serving around the European Continent. This research paper examined the requirement for a continued United States forward military presence within Europe from a strategic viewpoint to determine if said presence is strategically necessary and vital to United States interests. Research and analysis lead to the conclusion that the United States needs to continue its forward military presence in Europe. This recommendation is based on the following benefits of a forward military presence in Europe: expeditious access into that region of the world; basis for cooperation between European countries and the United States; the ability to influence events in that region of the world; an exercised and measured military inter-operability capability; and strategic flexibility in support of the war on terrorism and confrontations with rogue nations in the surrounding area. These advantages, when weighed against the disadvantages (potential entanglement in European affairs; legal concerns; force protection issues; and disincentive for Europe to invest in defense) provide overwhelming benefits and justify a continued United States forward military presence in Europe.
- Published
- 2003
56. O.7 Systemic delivery of RNase H-active antisense oligonucleotides reverses RNA dominance in a mouse model of myotonic dystrophy
- Author
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Charles A. Thornton, Andrew Leger, Sanjay K. Pandey, C.F. Bennett, Masayuki Nakamori, Bruce M. Wentworth, S H Cheng, Thurman M. Wheeler, and A.R. MacLeod
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Genetics ,biology ,RNA ,medicine.disease ,Myotonic dystrophy ,Molecular biology ,Neurology ,Pediatrics, Perinatology and Child Health ,Antisense oligonucleotides ,medicine ,biology.protein ,Neurology (clinical) ,RNase H ,Genetics (clinical) ,Dominance (genetics) - Published
- 2011
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57. Letters to the Editor
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Thurman, M. D., primary
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- 2009
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58. Myotonic dystrophy: RNA-mediated muscle disease
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Wheeler, Thurman M, primary and Thornton, Charles A, additional
- Published
- 2007
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59. Case Records of the Massachusetts General Hospital. Case 30-2015: A 50-Year-Old Man with Cardiogenic Shock.
- Author
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Wheeler, Thurman M., Baker, Joshua N., Chad, David A., Zilinski, Jodi L., Verzosa, Stacey, and Mordes, Daniel A.
- Abstract
A 50-year-old man with a history of cardiomyopathy and progressive muscle weakness was admitted with cardiogenic shock. Electroencephalography showed total suppression of cerebral activity; ventilator support was withdrawn, and he died. An autopsy was performed. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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60. 34. Phi C31 Integrase System Enhances Dystrophin Gene Expression in Skeletal Muscle of Mouse Models for Duchenne Muscular Dystrophy
- Author
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Bertoni, Carmen, primary, Jarrahian, Sohail, additional, Wheeler, Thurman M., additional, Li, Yining, additional, Olivares, Eric C., additional, Calos, Michele P., additional, and Rando, Thomas A., additional
- Published
- 2006
- Full Text
- View/download PDF
61. Enhancement of plasmid-mediated gene therapy for muscular dystrophy by directed plasmid integration
- Author
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Bertoni, Carmen, primary, Jarrahian, Sohail, additional, Wheeler, Thurman M., additional, Li, Yining, additional, Olivares, Eric C., additional, Calos, Michele P., additional, and Rando, Thomas A., additional
- Published
- 2005
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- View/download PDF
62. 265. Enhanced Plasmid-Mediated Dystrophin Expression in the mdx Mouse Model for Duchenne Muscular Dystrophy by a PhiC31 Integrase Plasmid System
- Author
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Sohail Jarrahian, Thomas A. Rando, Eric C. Olivares, Michele P. Calos, Thurman M. Wheeler, Yining Li, and Carmen Bertoni
- Subjects
musculoskeletal diseases ,Pharmacology ,congenital, hereditary, and neonatal diseases and abnormalities ,mdx mouse ,biology ,Duchenne muscular dystrophy ,Genetic enhancement ,medicine.disease ,Molecular biology ,Cell biology ,Plasmid ,Drug Discovery ,Gene expression ,Utrophin ,Genetics ,medicine ,biology.protein ,Molecular Medicine ,Dystrophin ,ITGA7 ,Molecular Biology - Abstract
Duchenne muscular dystrophy is caused by lack of dystrophin expression in skeletal muscles and is characterized by progressive degeneration of muscle fibers. To be effective, gene therapy approaches to DMD need to target a large number of fibers in the muscle, and the distribution of dystrophin through the fiber length needs to be sufficient to prevent fiber degeneration. Plasmid-based gene therapies have been shown to be a valid approach to the treatment of a variety of disorders including DMD. Concerns, however, have been raised about the ability of extrachromosomal vectors to sustain gene expression for prolonged periods of time at levels that are therapeutic.
- Published
- 2005
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63. 810. Site-Specific Integration Enhances Expression of DNA Introduced into Skeletal Muscle
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Sohail Jarrahian, Thomas A. Rando, Michele P. Calos, Christopher H. Contag, Eric C. Olivares, Carmen Bertoni, Thurman M. Wheeler, and Timothy C. Doyle
- Subjects
Pharmacology ,biology ,Genetic enhancement ,Electroporation ,fungi ,Molecular biology ,Integrase ,Insertional mutagenesis ,Plasmid ,Complementary DNA ,Drug Discovery ,Genetics ,biology.protein ,Molecular Medicine ,Luciferase ,Molecular Biology ,Gene - Abstract
Non-viral approaches to gene therapy have often been limited by transient expression of delivered genes. Permanent integration of therapeutic genes into the host genome holds promise for lasting expression of the deficient or defective protein. Integration that is site-specific can limit the hazards of insertional mutagenesis. Here we demonstrate a novel non-viral approach to gene therapy for muscle disease. We used phage phiC31 integrase to catalyze unidirectional, site-specific integration of incoming plasmid DNA carrying the luciferase gene and an attB site into pseudo attP sites in the genomes of muscle fibers. In vivo bioluminescent imaging was used to assess the levels of luciferase expression, as a measure of gene transfer and integration into mouse leg skeletal muscle. in vivo imaging demonstrated that electroporation following intramuscular injection of plasmid DNA increased initial luciferase activity by 1-2 orders of magnitude. Intramuscular injection of the luciferase-attB plasmid together with a plasmid expressing the phiC31 integrase produced persistent levels of expression that were 5-10 fold higher than the levels seen without integrase. Genomic integration was verified by performing PCR on muscle DNA using primers spanning a known hotspot pseudo attP site for phiC31–mediated integration in mouse liver cells. Four out of four muscles that received integrase and the attB plasmid were positive for integration events at this site. Application of this site-specific integration technology to gene therapy for muscular dystrophies may provide long-term, sustained amelioration of the disease phenotype. Delivery of wild type dystrophin cDNA into dystrophin-deficient muscles using the phiC31 integrase system is currently under investigation.
- Published
- 2004
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64. Identification and Characterization of Modified Antisense Oligonucleotides Targeting DMPKin Mice and Nonhuman Primates for the Treatment of Myotonic Dystrophy Type 1▪
- Author
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Pandey, Sanjay K., Wheeler, Thurman M., Justice, Samantha L., Kim, Aneeza, Younis, Husam S., Gattis, Danielle, Jauvin, Dominic, Puymirat, Jack, Swayze, Eric E., Freier, Susan M., Bennett, C. Frank, Thornton, Charles A., and MacLeod, A. Robert
- Abstract
Myotonic dystrophy type 1 (DM1) is the most common form of muscular dystrophy in adults. DM1 is caused by an expanded CTG repeat in the 3′-untranslated region of DMPK, the gene encoding dystrophia myotonica protein kinase (DMPK). Antisense oligonucleotides (ASOs) containing 2′,4′-constrained ethyl-modified (cEt) residues exhibit a significantly increased RNA binding affinity and in vivo potency relative to those modified with other 2′-chemistries, which we speculated could translate to enhanced activity in extrahepatic tissues, such as muscle. Here, we describe the design and characterization of a cEt gapmer DMPK ASO (ISIS 486178), with potent activity in vitro and in vivo against mouse, monkey, and human DMPK. Systemic delivery of unformulated ISIS 486718 to wild-type mice decreased DMPKmRNA levels by up to 90% in liver and skeletal muscle. Similarly, treatment of either human DMPK transgenic mice or cynomolgus monkeys with ISIS 486178 led to up to 70% inhibition of DMPK in multiple skeletal muscles and ∼50% in cardiac muscle in both species. Importantly, inhibition of DMPK was well tolerated and was not associated with any skeletal muscle or cardiac toxicity. Also interesting was the demonstration that the inhibition of DMPKmRNA levels in muscle was maintained for up to 16 and 13 weeks post-treatment in mice and monkeys, respectively. These results demonstrate that cEt-modified ASOs show potent activity in skeletal muscle, and that this attractive therapeutic approach warrants further clinical investigation to inhibit the gain-of-function toxic RNA underlying the pathogenesis of DM1.
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- 2015
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65. A STUDY ON IMPROVING LABORATORY EFFECTIVENESS.
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Huebner, Thurman M.
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- 1938
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66. A STUDY ON IMPROVING LABORATORY EFFECTIVENESS
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Thurman M. Huebner
- Subjects
Mathematics (miscellaneous) ,History and Philosophy of Science ,Physics and Astronomy (miscellaneous) ,Engineering (miscellaneous) ,Education - Published
- 1938
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67. A Logical Classification of and Recommendations for the Utah Education Law
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White, Thurman M.
- Subjects
classification ,Utah ,education law ,Education - Abstract
As our society becomes more complex, it follows that the laws governing this society become more numerous and more complicated. Problems arise relative to local, state, and federal control, necessitating further interpretation and ultimately new laws. Th e areas where legal confusion is most obvious are those subject to control by all levels of government: local, state, and federal.
- Published
- 1967
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68. Comparing scale-up approaches to predict granular activated carbon absorber performance for micropollutant removal
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Reinert, A. M., Kennedy, A., Scott Summers, R., Imma Ferrer, Thurman, M., and Knappe, D.
69. Scale-up of the GAC adsorption of trace organic compounds
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Kennedy, A., Reinert, A., Summers, R. S., Imma Ferrer, Thurman, M., and Knappe, D. R. U.
70. Review
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Thurman, M. E., primary
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- 1965
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71. Review
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Thurman, M. E., primary
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- 1967
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72. Recent Californiana: A Check-List of Publications Relating to California
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Thurman, M. E., primary
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- 1961
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73. Correction of myotonic dystrophy in mouse models by antisense targeting of nuclear-retained RNA.
- Author
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Thornton, Charles, Wheeler, Thurman M., Leger, Andrew J., Pandey, Sanjay K., MacLeod, A. Robert, Nakamori, Masayuki, Cheng, Seng H., Wentworth, Bruce M., and Bennet, C. Frank
- Subjects
- *
MYOTONIA atrophica , *ANTISENSE RNA , *THERAPEUTICS - Abstract
An abstract of the article "Correction of Myotonic Dystrophy in Mouse Models by Antisense Targeting of Nuclear-Retained RNA," by Charles Thornton, Thurman M. Wheeler, Andrew J. Leger, Sanjay K. Pandey, A. Robert MacLeod, Masayuki Nakamori, Seng H. Cheng et al, is presented.
- Published
- 2012
74. A study of the temporal variability of atrazine in private well water. Part I: Study design, implementation, and database development
- Author
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Pinsky, P., Lorber, M., Kross, B., Wilkins, A., Burmeister, L., Johnson, K., Hallberg, G., and Thurman, M.
- Subjects
ATRAZINE ,METHODOLOGY ,PESTICIDES ,GROUNDWATER monitoring - Abstract
In 1988, the Iowa Department of Natural Resources, along with the University of Iowa conducted the Statewide Rural Well Water Survey, commonly known as SWRL. A total of 686 private rural drinking water wells was selected by use of a probability sample and tested for pesticides and nitrates. Sixty-eight of these wells, the '10% repeat' wells, were additionally sampled in October, 1990 and June, 1991. Starting in November, 1991, the University of Iowa, with sponsorship from the United States Environmental Protection Agency, revisited these wells to begin a study of the temporal variability of atrazine and nitrates in wells. Other wells, which had originally tested positive for atrazine in SWRL but were not in the 10% repeat population, were added to the study population. Temporal sampling for a year-long period began in February of 1992 and concluded in January of 1993. All wells were sampled monthly, one subset was sampled weekly, and a second subset was sampled for 14-day consecutive periods. Two unique aspects of thisstudy were the use of an immunoassay technique to screen for triazines before gas chromatography/mass spectrometry (GC/MS) analysis and quantification of atrazine, and the use of well owners to sample the wells. A total of 1771 samples from 83 wells are in the final data base for this study. This paper reviews the study design, the analyticalmethodologies, and development of the data base. A companion paper (Pinsky et al., 1997) discusses the analysis of the data from this survey. [ABSTRACT FROM AUTHOR]
- Published
- 1997
75. Freeze-up prevention device for a heat pump
- Author
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Thurman, M
- Published
- 1977
76. Efficient trapping and destruction of SARS-CoV-2 using PECO-assisted Molekule air purifiers in the laboratory and real-world settings.
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Acharya A, Surbaugh K, Thurman M, Wickramaratne C, Myers P, Mittal R, Pandey K, Klug E, Stein SJ, Ravnholdt AR, Herrera VL, Rivera DN, Williams P, Santarpia JL, Kaushik A, Dhau JS, and Byrareddy SN
- Subjects
- Humans, SARS-CoV-2, COVID-19 Testing, Respiratory Aerosols and Droplets, COVID-19, Air Filters, Air Pollution, Indoor prevention & control
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted human-to-human via aerosols and air-borne droplets. Therefore, capturing and destroying viruses from indoor premises are essential to reduce the probability of human exposure and virus transmission. While the heating, ventilation, and air conditioning (HVAC) systems help in reducing the indoor viral load, a targeted approach is required to effectively remove SARS-CoV-2 from indoor air to address human exposure concerns. The present study demonstrates efficient trapping and destruction of SARS-CoV-2 via nano-enabled filter technology using the UV-A-stimulated photoelectrochemical oxidation (PECO) process. Aerosols containing SARS-CoV-2 were generated by nebulization inside an air-controlled test chamber where an air purifier (Air Mini+) was placed. The study demonstrated the efficient removal of SARS-CoV-2 (99.98 %) from the test chamber in less than two minutes and PECO-assisted destruction (over 99%) on the filtration media in 1 h. Furthermore, in a real-world scenario, the Molekule Air-Pro air purifier removed SARS-CoV-2 (a negative RT-qPCR result post-running the filter device) from the circulating air in a COVID-19 testing facility. Overall, the ability of two FDA-approved class II medical devices, Molekule Air-Mini+ and Air-Pro air purifiers, to remove and destroy SARS-CoV-2 in indoor settings was successfully demonstrated. The study indicates that as the "tripledemic" of COVID-19, influenza, and respiratory syncytial virus (RSV) overwhelm the healthcare facilities in the USA, the use of a portable air filtration device will help contain the spread of the viruses in close door facilities, such as in schools and daycare facilities., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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77. Proteomic landscape of astrocytes and pericytes infected with HIV/SARS-CoV-2 mono/co-infection, impacting on neurological complications.
- Author
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Acharya A, Ambikan AT, Thurman M, Malik MR, Dyavar SR, Végvári Á, Neogi U, and Byrareddy SN
- Abstract
Background: Although most individuals recover from coronavirus disease 2019 (COVID-19) within a few weeks, some people continue to experience a wide range of symptoms known as post-acute sequelae of SARS-CoV-2 (PASC) or long COVID. Majority of patients with PASC develop neurological disorders like brain fog, fatigue, mood swings, sleep disorders, loss of smell and test among others collectively called neuro-PASC. While the people living with HIV (PWH) do not have a higher risk of developing severe disease and mortality/morbidity due to COVID-19. As a large section of PWH suffered from HIV-associated neurocognitive disorders (HAND), it is essential to understand the impact of neuro-PASC on people with HAND. In pursuit of this, we infected HIV/SARS-CoV-2 alone or together in primary human astrocytes and pericytes and performed proteomics to understand the impact of co-infection in the central nervous system., Methods: Primary human astrocytes and pericytes were infected with SARS-CoV-2 or HIV or HIV + SARS-CoV-2. The concentration of HIV and SARS-CoV-2 genomic RNA in the culture supernatant was quantified using reverse transcriptase quantitative real time polymerase chain reaction (RT-qPCR). This was followed by a quantitative proteomics analysis of mock, HIV, SARS-CoV-2, and HIV + SARS-CoV-2 infected astrocytes and pericytes to understand the impact of the virus in CNS cell types., Results: Both healthy and HIV-infected astrocytes and pericytes support abortive/low level of SARS-CoV-2 replication. In both mono-infected and co-infected cells, we observe a modest increase in the expression of SARS-CoV-2 host cell entry factors (ACE2, TMPRSS2, NRP1, and TRIM28) and inflammatory mediators (IL-6, TNF-α, IL-1β and IL-18). Quantitative proteomic analysis has identified uniquely regulated pathways in mock vs SARS-CoV-2, mock vs HIV + SARS-CoV-2, and HIV vs HIV + SARS-CoV-2 infected astrocytes and pericytes. The gene set enrichment analysis revealed that the top ten enriched pathways are linked to several neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis., Conclusions: Our study emphasizes the significance of long-term monitoring of patients co-infected with HIV and SARS-CoV-2 to detect and understand the development of neurological abnormalities. By unraveling the molecular mechanisms involved, we can identify potential targets for future therapeutic interventions., Competing Interests: Competing interests The authors declare no competing interests.
- Published
- 2023
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78. Early treatment with anti-α 4 β 7 antibody facilitates increased gut macrophage maturity in SIV-infected rhesus macaques.
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Johnson SD, Knight LA, Kumar N, Olwenyi OA, Thurman M, Mehra S, Mohan M, and Byrareddy SN
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- Animals, Macaca mulatta, Antibodies therapeutic use, Macrophages, Simian Immunodeficiency Virus, Simian Acquired Immunodeficiency Syndrome, HIV Infections drug therapy
- Abstract
Despite advances in combination antiretroviral therapy (cART), people living with HIV (PLWH) continue to experience gastrointestinal dysfunction. Infusions of anti-α
4 β7 monoclonal antibodies (mAbs) have been proposed to increase virologic control during simian immunodeficiency virus (SIV) infection in macaques with mixed results. Recent evidences suggested that therapeutic efficacy of vedolizumab (a humanized anti-α4 β7 mAb), during inflammatory bowel diseases depends on microbiome composition, myeloid cell differentiation, and macrophage phenotype. We tested this hypothesis in SIV-infected, anti-α4 β7 mAb-treated macaques and provide flow cytometric and microscopic evidence that anti-α4 β7 administered to SIV-infected macaques increases the maturity of macrophage phenotypes typically lost in the small intestines during SIV disease progression. Further, this increase in mature macrophage phenotype was associated with tissue viral loads. These phenotypes were also associated with dysbiosis markers in the gut previously identified as predictors of HIV replication and immune activation in PLWH. These findings provide a novel model of anti-α4 β7 efficacy offering new avenues for targeting pathogenic mucosal immune response during HIV/SIV infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Johnson, Knight, Kumar, Olwenyi, Thurman, Mehra, Mohan and Byrareddy.)- Published
- 2022
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79. Systems biology analyses reveal enhanced chronic morphine distortion of gut-brain interrelationships in simian human immunodeficiency virus infected rhesus macaques.
- Author
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Olwenyi OA, Johnson SD, Bidokhti M, Thakur V, Pandey K, Thurman M, Acharya A, Uppada S, Callen S, Giavedoni L, Ranga U, Buch SJ, and Byrareddy SN
- Abstract
Background: Commonly used opioids, such as morphine have been implicated in augmented SIV/HIV persistence within the central nervous system (CNS). However, the extent of myeloid cell polarization and viral persistence in different brain regions remains unclear. Additionally, the additive effects of morphine on SIV/HIV dysregulation of gut-brain crosstalk remain underexplored. Therefore, studies focused on understanding how drugs of abuse such as morphine affect immune dynamics, viral persistence and gut-brain interrelationships are warranted., Materials and Methods: For a total of 9 weeks, rhesus macaques were ramped-up, and twice daily injections of either morphine ( n = 4) or saline ( n = 4) administered. This was later followed with infection with SHIVAD8EO variants. At necropsy, mononuclear cells were isolated from diverse brain [frontal lobe, cerebellum, medulla, putamen, hippocampus (HIP) and subventricular zone (SVZ)] and gut [lamina propria (LP) and muscularis (MUSC) of ascending colon, duodenum, and ileum] regions. Multiparametric flow cytometry was used to were profile for myeloid cell polarity/activation and results corroborated with indirect immunofluorescence assays. Simian human immunodeficiency virus (SHIV) DNA levels were measured with aid of the digital droplet polymerase chain reaction (PCR) assay. Luminex assays were then used to evaluate soluble plasma/CSF biomarker levels. Finally, changes in the fecal microbiome were evaluated using 16S rRNA on the Illumina NovaSeq platform., Results: Flow Cytometry-based semi-supervised analysis revealed that morphine exposure led to exacerbated M1 (CD14/CD16)/M2 (CD163/CD206) polarization in activated microglia that spanned across diverse brain regions. This was accompanied by elevated SHIV DNA within the sites of neurogenesis-HIP and SVZ. HIP/SVZ CD16+ activated microglia positively correlated with SHIV DNA levels in the brain ( r = 0.548, p = 0.042). Simultaneously, morphine dependence depleted butyrate-producing bacteria, including Ruminococcus ( p = 0.05), Lachnospira ( p = 0.068) genera and Roseburia_sp_831b ( p = 0.068). Finally, morphine also altered the regulation of CNS inflammation by reducing the levels of IL1 Receptor antagonist (IL1Ra)., Conclusion: These findings are suggestive that morphine promotes CNS inflammation by altering receptor modulation, increasing myeloid brain activation, distorting gut-brain crosstalk, and causing selective enhancement of SHIV persistence in sites of neurogenesis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Olwenyi, Johnson, Bidokhti, Thakur, Pandey, Thurman, Acharya, Uppada, Callen, Giavedoni, Ranga, Buch and Byrareddy.)
- Published
- 2022
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80. Transformation of dolutegravir into an ultra-long-acting parenteral prodrug formulation.
- Author
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Deodhar S, Sillman B, Bade AN, Avedissian SN, Podany AT, McMillan JM, Gautam N, Hanson B, Dyavar Shetty BL, Szlachetka A, Johnston M, Thurman M, Munt DJ, Dash AK, Markovic M, Dahan A, Alnouti Y, Yazdi A, Kevadiya BD, Byrareddy SN, Cohen SM, Edagwa B, and Gendelman HE
- Subjects
- Heterocyclic Compounds, 3-Ring, Humans, Oxazines therapeutic use, Piperazines, Pyridones therapeutic use, HIV Infections drug therapy, HIV Integrase Inhibitors, Prodrugs pharmacology
- Abstract
Ultra-long-acting integrase strand transfer inhibitors were created by screening a library of monomeric and dimeric dolutegravir (DTG) prodrug nanoformulations. This led to an 18-carbon chain modified ester prodrug nanocrystal (coined NM2DTG) with the potential to sustain yearly dosing. Here, we show that the physiochemical and pharmacokinetic (PK) formulation properties facilitate slow drug release from tissue macrophage depot stores at the muscle injection site and adjacent lymphoid tissues following single parenteral injection. Significant plasma drug levels are recorded up to a year following injection. Tissue sites for prodrug hydrolysis are dependent on nanocrystal dissolution and prodrug release, drug-depot volume, perfusion, and cell-tissue pH. Each affect an extended NM2DTG apparent half-life recorded by PK parameters. The NM2DTG product can impact therapeutic adherence, tolerability, and access of a widely used integrase inhibitor in both resource limited and rich settings to reduce HIV-1 transmission and achieve optimal treatment outcomes., (© 2022. The Author(s).)
- Published
- 2022
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81. Improved Database Filtering Technology Enables More Efficient Ab Initio Design of Potent Peptides against Ebola Viruses.
- Author
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Ripperda T, Yu Y, Verma A, Klug E, Thurman M, Reid SP, and Wang G
- Abstract
The rapid mutations of viruses such as SARS-CoV-2 require vaccine updates and the development of novel antiviral drugs. This article presents an improved database filtering technology for a more effective design of novel antiviral agents. Different from the previous approach, where the most probable parameters were obtained stepwise from the antimicrobial peptide database, we found it possible to accelerate the design process by deriving multiple parameters in a single step during the peptide amino acid analysis. The resulting peptide DFTavP1 displays the ability to inhibit Ebola virus. A deviation from the most probable peptide parameters reduces antiviral activity. The designed peptides appear to block viral entry. In addition, the amino acid signature provides a clue to peptide engineering to gain cell selectivity. Like human cathelicidin LL-37, our engineered peptide DDIP1 inhibits both Ebola and SARS-CoV-2 viruses. These peptides, with broad antiviral activity, may selectively disrupt viral envelopes and offer the lasting efficacy required to treat various RNA viruses, including their emerging mutants.
- Published
- 2022
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82. PI3K-α/mTOR/BRD4 inhibitor alone or in combination with other anti-virals blocks replication of SARS-CoV-2 and its variants of concern including Delta and Omicron.
- Author
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Acharya A, Pathania AS, Pandey K, Thurman M, Vann KR, Kutateladze TG, Challagundala KB, Durden DL, and Byrareddy SN
- Subjects
- Antiviral Agents pharmacology, Cell Cycle Proteins antagonists & inhibitors, Humans, Phosphatidylinositol 3-Kinases, TOR Serine-Threonine Kinases antagonists & inhibitors, Transcription Factors antagonists & inhibitors, Virus Replication drug effects, Phosphoinositide-3 Kinase Inhibitors pharmacology, SARS-CoV-2 drug effects, COVID-19 Drug Treatment
- Published
- 2022
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83. Discovery and Evaluation of Entry Inhibitors for SARS-CoV-2 and Its Emerging Variants.
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Acharya A, Pandey K, Thurman M, Klug E, Trivedi J, Sharma K, Lorson CL, Singh K, and Byrareddy SN
- Subjects
- Adenosine Monophosphate analogs & derivatives, Adenosine Monophosphate pharmacology, Alanine analogs & derivatives, Alanine pharmacology, Angiotensin-Converting Enzyme 2 metabolism, Animals, Antiviral Agents pharmacology, Chemistry, Pharmaceutical methods, Chlorocebus aethiops, Computer Simulation, Drug Design, HEK293 Cells, Humans, Inhibitory Concentration 50, Models, Molecular, Molecular Dynamics Simulation, Mutation, Protein Binding, Protein Domains, Protein Interaction Domains and Motifs, Spike Glycoprotein, Coronavirus, Vero Cells, COVID-19 virology, SARS-CoV-2 drug effects, COVID-19 Drug Treatment
- Abstract
The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the coronavirus disease 19 (COVID-19) pandemic. Despite unprecedented research and developmental efforts, SARS-CoV-2-specific antivirals are still unavailable for the treatment of COVID-19. In most instances, SARS-CoV-2 infection initiates with the binding of Spike glycoprotein to the host cell ACE2 receptor. Utilizing the crystal structure of the ACE2/Spike receptor-binding domain (S-RBD) complex (PDB file 6M0J) in a computer-aided drug design approach, we identified and validated five potential inhibitors of S-RBD and ACE-2 interaction. Two of the five compounds, MU-UNMC-1 and MU-UNMC-2, blocked the entry of pseudovirus particles expressing SARS-CoV-2 Spike glycoprotein. In live SARS-CoV-2 infection assays, both compounds showed antiviral activity with IC
50 values in the micromolar range (MU-UNMC-1: IC50 = 0.67 μM and MU-UNMC-2: IC50 = 1.72 μM) in human bronchial epithelial cells. Furthermore, MU-UNMC-1 and MU-UNMC-2 effectively blocked the replication of rapidly transmitting variants of concern: South African variant B.1.351 (IC50 = 9.27 and 3.00 μM) and Scotland variant B.1.222 (IC50 = 2.64 and 1.39 μM), respectively. Following these assays, we conducted "induced-fit (flexible) docking" to understand the binding mode of MU-UNMC-1/MU-UNMC-2 at the S-RBD/ACE2 interface. Our data showed that mutation N501Y (present in B.1.351 variant) alters the binding mode of MU-UNMC-2 such that it is partially exposed to the solvent and has reduced polar contacts. Finally, MU-UNMC-2 displayed high synergy with remdesivir, the only approved drug for treating hospitalized COVID-19 patients. IMPORTANCE The ongoing coronavirus infectious disease 2019 (COVID-19) pandemic is caused by a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 207 million people have been infected globally, and 4.3 million have died due to this viral outbreak. While a few vaccines have been deployed, a SARS-CoV-2-specific antiviral for the treatment of COVID-19 is yet to be approved. As the interaction of SARS-CoV-2 Spike protein with ACE2 is critical for cellular entry, using a combination of a computer-aided drug design (CADD) approach and cell-based in vitro assays, we report the identification of five potential SARS-CoV-2 entry inhibitors. Out of the five, two compounds (MU-UNMC-1 and MU-UNMC-2) have antiviral activity against ancestral SARS-CoV-2 and emerging variants from South Africa and Scotland. Furthermore, MU-UNMC-2 acts synergistically with remdesivir (RDV), suggesting that RDV and MU-UNMC-2 can be developed as a combination therapy to treat COVID-19 patients.- Published
- 2021
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84. Mental Health Issues During and After COVID-19 Vaccine Era.
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Pandey K, Thurman M, Johnson SD, Acharya A, Johnston M, Klug EA, Olwenyi OA, Rajaiah R, and Byrareddy SN
- Subjects
- COVID-19 Vaccines administration & dosage, Communicable Disease Control, Humans, Longitudinal Studies, Mental Health trends, Pandemics prevention & control, Public Health, SARS-CoV-2 pathogenicity, Vaccination trends, Vaccination Refusal trends, Vaccines, COVID-19 psychology, Vaccination psychology, Vaccination Refusal psychology
- Abstract
The COVID-19 pandemic has persisted for more than a year, and post-COVID-19 sequelae of neurological complications, including direct and indirect effects on the central nervous system (CNS), have been recognized. There is a plethora of evidence for neurological, cognitive, and emotional deficits in COVID-19 patients. Acute neurological symptoms like neuroinflammation, cognitive impairment, loss of smell, and brain stroke are common direct effects among SARS-CoV-2 infected individuals. Work-associated stress, lockdowns, social distancing, and quarantine in response to contain SARS-CoV-2 have also affected the mental health of large populations, regardless of age. Public health emergencies have affected individuals and communities, resulting in emotional reactions and unhealthy behaviors. Although vaccines have been widely distributed and administered among large populations, vaccine hesitancy still exists and may be due to apprehension about vaccine efficacy, preliminary trials, and associated side effects. This review highlights the impact of COVID-19 on the CNS by outlining direct and indirect effects and factors contributing to the decline in people's mental health throughout the COVID-19 pandemic both during and after vaccine administration. Furthermore, we also discuss reasons for vaccine hesitancy and why some groups of people are deprived of vaccines. Finally, we touched upon the social determinants of mental health and their impact on disadvantaged populations during times of crisis which may help policymakers set up some action plans to mitigate the COVID-19 mental health turmoil during this ongoing pandemic., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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85. Diminished Peripheral CD29hi Cytotoxic CD4+ T Cells Are Associated With Deleterious Effects During SIV Infection.
- Author
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Olwenyi OA, Johnson SD, Pandey K, Thurman M, Acharya A, Buch SJ, Fox HS, Podany AT, Fletcher CV, and Byrareddy SN
- Subjects
- Animals, Anti-Retroviral Agents pharmacology, Cells, Cultured, Cytokines metabolism, Disease Models, Animal, Host-Pathogen Interactions, Macaca mulatta, Morphine pharmacology, Phenotype, Simian Acquired Immunodeficiency Syndrome drug therapy, Simian Acquired Immunodeficiency Syndrome metabolism, Simian Acquired Immunodeficiency Syndrome virology, Simian Immunodeficiency Virus drug effects, Simian Immunodeficiency Virus growth & development, T-Lymphocytes, Cytotoxic drug effects, T-Lymphocytes, Cytotoxic metabolism, T-Lymphocytes, Cytotoxic virology, Viral Load, Virus Replication, Cytotoxicity, Immunologic, Integrin beta1 metabolism, Simian Acquired Immunodeficiency Syndrome immunology, Simian Immunodeficiency Virus immunology, T-Lymphocytes, Cytotoxic immunology
- Abstract
Cytotoxic CD4+ T cells (CD4+ CTLs) limit HIV pathogenesis, as evidenced in elite controllers (a subset of individuals who suppress the virus without the need for therapy). CD4+ CTLs have also been shown to kill HIV-infected macrophages. However, little is known about their contribution towards HIV persistence, how they are affected following exposure to immune modulators like morphine, and what factors maintain their frequencies and function. Further, the lack of robust markers to identify CD4+ CTLs in various animal models limits understanding of their role in HIV pathogenesis. We utilized various PBMC samples obtained from SIV infected and cART treated rhesus macaques exposed to morphine or saline and subjected to flow cytometry evaluations. Thereafter, we compared and correlated the expression of CD4+ CTL-specific markers to viral load and viral reservoir estimations in total CD4+ T cells. We found that CD29 could be reliably used as a marker to identify CD4+ CTLs in rhesus macaques since CD29hi CD4+ T cells secrete higher cytotoxic and proinflammatory cytokines following PMA/ionomycin or gag stimulation. In addition, this immune cell subset was depleted during untreated SIV infection. Strikingly, we also observed that early initiation of cART reconstitutes depleted CD29hi CD4+ T cells and restores their function. Furthermore, we noted that morphine exposure reduced the secretion of proinflammatory cytokines/cytotoxic molecules in CD29hi CD4+ T cells. Lastly, increased functionality of CD29hi CD4+ T cells as depicted by elevated levels of either IL-21 or granzyme B hi T Bet+ gag specific responses were linked to limiting the size of the replication-competent reservoir during cART treatment. Collectively, our data suggest that CD4+ CTLs are crucial in limiting SIV pathogenesis and persistence., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Olwenyi, Johnson, Pandey, Thurman, Acharya, Buch, Fox, Podany, Fletcher and Byrareddy.)
- Published
- 2021
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86. Therapeutic implications of SARS-CoV-2 dysregulation of the gut-brain-lung axis.
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Johnson SD, Olwenyi OA, Bhyravbhatla N, Thurman M, Pandey K, Klug EA, Johnston M, Dyavar SR, Acharya A, Podany AT, Fletcher CV, Mohan M, Singh K, and Byrareddy SN
- Subjects
- Brain, Humans, Lung, Pandemics, Prospective Studies, COVID-19, SARS-CoV-2
- Abstract
The emergence and rapid spread of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused over 180 million confirmed cases resulting in over 4 million deaths worldwide with no clear end in sight for the coronavirus disease 19 (COVID-19) pandemic. Most SARS-CoV-2 exposed individuals experience mild to moderate symptoms, including fever, cough, fatigue, and loss of smell and taste. However, many individuals develop pneumonia, acute respiratory distress syndrome, septic shock, and multiorgan dysfunction. In addition to these primarily respiratory symptoms, SARS-CoV-2 can also infiltrate the central nervous system, which may damage the blood-brain barrier and the neuron's synapses. Resultant inflammation and neurodegeneration in the brain stem can further prevent efferent signaling to cranial nerves, leading to the loss of anti-inflammatory signaling and normal respiratory and gastrointestinal functions. Additionally, SARS-CoV-2 can infect enterocytes resulting in gut damage followed by microbial dysbiosis and translocation of bacteria and their byproducts across the damaged epithelial barrier. As a result, this exacerbates pro-inflammatory responses both locally and systemically, resulting in impaired clinical outcomes. Recent evidence has highlighted the complex interactions that mutually modulate respiratory, neurological, and gastrointestinal function. In this review, we discuss the ways SARS-CoV-2 potentially disrupts the gut-brain-lung axis. We further highlight targeting specific responses to SARS-CoV-2 for the development of novel, urgently needed therapeutic interventions. Finally, we propose a prospective related to the individuals from Low- and Middle-Income countries. Here, the underlying propensity for heightened gut damage/microbial translocation is likely to result in worse clinical outcomes during this COVID-19 pandemic., Competing Interests: Conflict-of-interest statement: Authors declare no conflict of interests for this article., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
87. Discovery and in-vitro evaluation of potent SARS-CoV-2 entry inhibitors.
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Acharya A, Pandey K, Thurman M, Klug E, Trivedi J, Lorson CL, Singh K, and Byrareddy SN
- Abstract
SARS-CoV-2 infection initiates with the attachment of spike protein to the ACE2 receptor. While vaccines have been developed, no SARS-CoV-2 specific small molecule inhibitors have been approved. Herein, utilizing the crystal structure of the ACE2/Spike receptor binding domain (S-RBD) complex in computer-aided drug design (CADD) approach, we docked ∼8 million compounds within the pockets residing at S-RBD/ACE2 interface. Five best hits depending on the docking score, were selected and tested for their in vitro efficacy to block SARS-CoV-2 replication. Of these, two compounds (MU-UNMC-1 and MU-UNMC-2) blocked SARS-CoV-2 replication at sub-micromolar IC
50 in human bronchial epithelial cells (UNCN1T) and Vero cells. Furthermore, MU-UNMC-2 was highly potent in blocking the virus entry by using pseudoviral particles expressing SARS-CoV-2 spike. Finally, we found that MU-UNMC-2 is highly synergistic with remdesivir (RDV), suggesting that minimal amounts are needed when used in combination with RDV, and has the potential to develop as a potential entry inhibitor for COVID-19.- Published
- 2021
- Full Text
- View/download PDF
88. Blockade of SARS-CoV-2 infection in vitro by highly potent PI3K-α/mTOR/BRD4 inhibitor.
- Author
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Acharya A, Pandey K, Thurman M, Challagundala KB, Vann KR, Kutateladze TG, Morales GA, Durden DL, and Byrareddy SN
- Abstract
Pathogenic viruses like SARS-CoV-2 and HIV hijack the host molecular machinery to establish infection and survival in infected cells. This has led the scientific community to explore the molecular mechanisms by which SARS-CoV-2 infects host cells, establishes productive infection, and causes life-threatening pathophysiology. Very few targeted therapeutics for COVID-19 currently exist, such as remdesivir. Recently, a proteomic approach explored the interactions of 26 of 29 SARS-CoV-2 proteins with cellular targets in human cells and identified 67 interactions as potential targets for drug development. Two of the critical targets, the bromodomain and extra-terminal domain proteins (BETs): BRD2/BRD4 and mTOR, are inhibited by the dual inhibitory small molecule SF2523 at nanomolar potency. SF2523 is the only known mTOR PI3K-α/(BRD2/BRD4) inhibitor with potential to block two orthogonal pathways necessary for SARS-CoV-2 pathogenesis in human cells. Our results demonstrate that SF2523 effectively blocks SARS-CoV-2 replication in lung bronchial epithelial cells in vitro , showing an IC
50 value of 1.5 µM, comparable to IC50 value of remdesivir (1.1 µM). Further, we demonstrated that the combination of doses of SF2523 and remdesivir is highly synergistic: it allows for the reduction of doses of SF2523 and remdesivir by 25-fold and 4-fold, respectively, to achieve the same potency observed for a single inhibitor. Because SF2523 inhibits two SARS-CoV-2 driven pathogenesis mechanisms involving BRD2/BRD4 and mTOR signaling, our data suggest that SF2523 alone or in combination with remdesivir could be a novel and efficient therapeutic strategy to block SARS-CoV-2 infection and hence be beneficial in preventing severe COVID-19 disease evolution., One Sentence Summary: Evidence of in silico designed chemotype (SF2523) targeting PI3K-α/mTOR/BRD4 inhibits SARS-CoV-2 infection and is highly synergistic with remdesivir.- Published
- 2021
- Full Text
- View/download PDF
89. Chronic morphine administration differentially modulates viral reservoirs in SIVmac251 infected rhesus macaque model.
- Author
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Acharya A, Olwenyi OA, Thurman M, Pandey K, Morsey BM, Lamberty B, Ferguson N, Callen S, Fang Q, Buch SJ, Fox HS, and Byrareddy SN
- Abstract
HIV persists in cellular reservoirs despite effective combined antiretroviral therapy (cART) and there is viremia flare up upon therapy interruption. Opioids modulate the immune system and suppress antiviral gene responses, which significantly impact people living with HIV (PLWH). However, the effect of opioids on viral reservoir dynamics remain elusive. Herein, we developed a morphine dependent SIVmac251 infected Rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. RMs on a morphine (or saline control) regimen were infected with SIVmac251. The cART was initiated in approximately half the animals five weeks post-infection, and morphine/saline administration continued until the end of the study. Among the untreated RM, we did not find any difference in plasma/CSF or in cell-associated DNA/RNA viral load in anatomical tissues. On the other hand, within the cART suppressed macaques, there was a reduction in cell-associated DNA load, intact proviral DNA levels, and in inducible SIV reservoir in lymph nodes (LNs) of morphine administered RMs. In distinction to LNs, in the CNS, the size of latent SIV reservoirs was higher in the CD11b+ microglia/macrophages in morphine dependent RMs. These results suggest that in the proposed model, morphine plays a differential role in SIV reservoirs by reducing the CD4+ T-cell reservoir in lymphoid tissues, while increasing the microglia/reservoir size in CNS tissue. The findings from this pre-clinical model will serve as a tool for screening therapeutic strategies to reduce/eliminate HIV reservoirs in opioid dependent PLWH. IMPORTANCE Identification and clearance of HIV reservoirs is a major challenge in achieving a cure for HIV. This is further complicated by co-morbidities that may alter the size of the reservoirs. There is an overlap between the risk factors for HIV and opioid abuse. Opiates have been recognized as prominent co-morbidities in HIV-infected populations. People infected with HIV also abusing opioids have immune modulatory effects and more severe neurological disease. However, the impact of opioid abuse on HIV reservoirs remains unclear. In this study, we used morphine dependent SIVmac251 infected rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. Our studies suggested that people with HIV who abuse opioids had higher reservoirs in CNS than the lymphoid system. Extrapolating the macaque findings in humans suggests that such differential modulation of HIV reservoirs among people living with HIV abusing opioids could be considered for future HIV cure research efforts., (Copyright © 2020 Acharya et al.)
- Published
- 2021
- Full Text
- View/download PDF
90. The slo-1 BK potassium channel interacts genetically with pmr-1 secretory pathway calcium ATPase during C. elegans embryonic cell migration.
- Author
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Thurman M, Sun H, Kubica S, and Praitis V
- Published
- 2021
- Full Text
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91. Biomarkers of Activation and Inflammation to Track Disparity in Chronological and Physiological Age of People Living With HIV on Combination Antiretroviral Therapy.
- Author
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Thurman M, Johnson S, Acharya A, Pallikkuth S, Mahesh M, and Byrareddy SN
- Subjects
- Animals, Drug Therapy, Combination methods, HIV Infections pathology, Humans, Aging metabolism, Anti-HIV Agents therapeutic use, Biomarkers metabolism, HIV Infections drug therapy, HIV Infections metabolism, Inflammation metabolism, Inflammation pathology
- Abstract
With advancement, prompt use, and increasing accessibility of antiretroviral therapy, people with HIV are living longer and have comparable lifespans to those negative for HIV. However, people living with HIV experience tradeoffs with quality of life often developing age-associated co-morbid conditions such as cancers, cardiovascular diseases, or neurodegeneration due to chronic immune activation and inflammation. This creates a discrepancy in chronological and physiological age, with HIV-infected individuals appearing older than they are, and in some contexts ART-associated toxicity exacerbates this gap. The complexity of the accelerated aging process in the context of HIV-infection highlights the need for greater understanding of biomarkers involved. In this review, we discuss markers identified in different anatomical sites of the body including periphery, brain, and gut, as well as markers related to DNA that may serve as reliable predictors of accelerated aging in HIV infected individuals as it relates to inflammatory state and immune activation., (Copyright © 2020 Thurman, Johnson, Acharya, Pallikkuth, Mahesh and Byrareddy.)
- Published
- 2020
- Full Text
- View/download PDF
92. Changes in Alternative Splicing as Pharmacodynamic Markers for Sudemycin D6.
- Author
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Thurman M, van Doorn J, Danzer B, Webb TR, and Stamm S
- Abstract
Objective: The aim of the study was to define pharmacodynamic markers for sudemycin D6, an experimental cancer drug that changes alternative splicing in human blood., Methods: Blood samples from 12 donors were incubated with sudemycin D6 for up to 24 hours, and at several time points total RNA from lymphocytes was prepared and the pre-messenger RNA (mRNA) splicing patterns were analyzed with reverse transcription-polymerase chain reaction., Results: Similar to immortalized cells, blood lymphocytes change alternative splicing due to sudemycin D6 treatment. However, lymphocytes in blood respond slower than immortalized cultured cells., Conclusions: Exon skipping in the DUSP11 and SRRM1 pre-mRNAs are pharmacodynamic markers for sudemycin D6 treatment and show effects beginning at 9 hours after treatment., Competing Interests: Declaration of conflicting interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2017
- Full Text
- View/download PDF
93. Identification of Novel Perfluoroalkyl Ether Carboxylic Acids (PFECAs) and Sulfonic Acids (PFESAs) in Natural Waters Using Accurate Mass Time-of-Flight Mass Spectrometry (TOFMS).
- Author
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Strynar M, Dagnino S, McMahen R, Liang S, Lindstrom A, Andersen E, McMillan L, Thurman M, Ferrer I, and Ball C
- Subjects
- Carboxylic Acids chemistry, Chemical Fractionation, Ethers analysis, Ethers chemistry, Fluorocarbons chemistry, Humans, North Carolina, Sulfonic Acids analysis, Sulfonic Acids chemistry, Water analysis, Water Pollutants, Chemical chemistry, Carboxylic Acids analysis, Fluorocarbons analysis, Spectrometry, Mass, Electrospray Ionization methods, Water Pollutants, Chemical analysis
- Abstract
Recent scientific scrutiny and concerns over exposure, toxicity, and risk have led to international regulatory efforts resulting in the reduction or elimination of certain perfluorinated compounds from various products and waste streams. Some manufacturers have started producing shorter chain per- and polyfluorinated compounds to try to reduce the potential for bioaccumulation in humans and wildlife. Some of these new compounds contain central ether oxygens or other minor modifications of traditional perfluorinated structures. At present, there has been very limited information published on these "replacement chemistries" in the peer-reviewed literature. In this study we used a time-of-flight mass spectrometry detector (LC-ESI-TOFMS) to identify fluorinated compounds in natural waters collected from locations with historical perfluorinated compound contamination. Our workflow for discovery of chemicals included sequential sampling of surface water for identification of potential sources, nontargeted TOFMS analysis, molecular feature extraction (MFE) of samples, and evaluation of features unique to the sample with source inputs. Specifically, compounds were tentatively identified by (1) accurate mass determination of parent and/or related adducts and fragments from in-source collision-induced dissociation (CID), (2) in-depth evaluation of in-source adducts formed during analysis, and (3) confirmation with authentic standards when available. We observed groups of compounds in homologous series that differed by multiples of CF2 (m/z 49.9968) or CF2O (m/z 65.9917). Compounds in each series were chromatographically separated and had comparable fragments and adducts produced during analysis. We detected 12 novel perfluoroalkyl ether carboxylic and sulfonic acids in surface water in North Carolina, USA using this approach. A key piece of evidence was the discovery of accurate mass in-source n-mer formation (H(+) and Na(+)) differing by m/z 21.9819, corresponding to the mass difference between the protonated and sodiated dimers.
- Published
- 2015
- Full Text
- View/download PDF
94. Twelve ways to improve collections.
- Author
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Thurman M
- Subjects
- Humans, Patient Credit and Collection, Practice Management, Dental economics
- Published
- 1992
95. Preliminary evaluation of the patient with high blood pressure.
- Author
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Janney JG Jr, Thurman M, Utley JH, and Aykent Y
- Subjects
- Diagnosis, Differential, Humans, Antihypertensive Agents therapeutic use, Hypertension diagnosis, Hypertension drug therapy
- Published
- 1965
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