1
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Cooper JC, Paul JE, Ramlawi N, Saengow C, Sharma A, Suslick BA, Ewoldt RH, Sottos NR, Moore JS. Reprocessability in Engineering Thermosets Achieved Through Frontal RingOpening Metathesis Polymerization. Adv Mater 2024:e2402627. [PMID: 38652482 DOI: 10.1002/adma.202402627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/12/2024] [Indexed: 04/25/2024]
Abstract
While valued for their durability and exceptional performance, crosslinked thermosets are challenging to recycle and reuse. Here, inherent reprocessability in industrially relevant polyolefin thermosetsis unveiled. Unlike prior methods, this approach eliminates the need to introduce exchangeable functionality to regenerate the material, relying instead on preserving the activity of the metathesis catalyst employed in the curing reaction. Frontal ring-opening metathesis polymerization (FROMP) proves critical to preserving this activity. Conditions controlling catalytic viability are explored to successfully reclaim performance across multiple generations of material, thus demonstrating long-term reprocessability. This straightforward and scalable remolding strategy is poised for widespread adoption. Given the anticipated growth in polyolefin thermosets, these findings represent an important conceptual advance in the pursuit of a fully circular lifecycle for thermoset polymers.
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Affiliation(s)
- Julian C Cooper
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Justine E Paul
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Nabil Ramlawi
- Department of Mechanical Science and Engineering, University of Illinois Urban-Champaign, Urbana, IL, 61801, USA
| | - Chaimongkol Saengow
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Mechanical Science and Engineering, University of Illinois Urban-Champaign, Urbana, IL, 61801, USA
| | - Anisha Sharma
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Benjamin A Suslick
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Randy H Ewoldt
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Mechanical Science and Engineering, University of Illinois Urban-Champaign, Urbana, IL, 61801, USA
| | - Nancy R Sottos
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jeffrey S Moore
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
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2
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AlFaraj Y, Mohapatra S, Shieh P, Husted KEL, Ivanoff DG, Lloyd EM, Cooper JC, Dai Y, Singhal AP, Moore JS, Sottos NR, Gomez-Bombarelli R, Johnson JA. A Model Ensemble Approach Enables Data-Driven Property Prediction for Chemically Deconstructable Thermosets in the Low-Data Regime. ACS Cent Sci 2023; 9:1810-1819. [PMID: 37780353 PMCID: PMC10540282 DOI: 10.1021/acscentsci.3c00502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Indexed: 10/03/2023]
Abstract
Thermosets present sustainability challenges that could potentially be addressed through the design of deconstructable variants with tunable properties; however, the combinatorial space of possible thermoset molecular building blocks (e.g., monomers, cross-linkers, and additives) and manufacturing conditions is vast, and predictive knowledge for how combinations of these molecular components translate to bulk thermoset properties is lacking. Data science could overcome these problems, but computational methods are difficult to apply to multicomponent, amorphous, statistical copolymer materials for which little data exist. Here, leveraging a data set with 101 examples, we introduce a closed-loop experimental, machine learning (ML), and virtual screening strategy to enable predictions of the glass transition temperature (Tg) of polydicyclopentadiene (pDCPD) thermosets containing cleavable bifunctional silyl ether (BSE) comonomers and/or cross-linkers with varied compositions and loadings. Molecular features and formulation variables are used as model inputs, and uncertainty is quantified through model ensembling, which together with heavy regularization helps to avoid overfitting and ultimately achieves predictions within <15 °C for thermosets with compositionally diverse BSEs. This work offers a path to predicting the properties of thermosets based on their molecular building blocks, which may accelerate the discovery of promising plastics, rubbers, and composites with improved functionality and controlled deconstructability.
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Affiliation(s)
- Yasmeen
S. AlFaraj
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States of America
| | - Somesh Mohapatra
- Department
of Materials Science and Engineering, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States of America
| | - Peyton Shieh
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States of America
| | - Keith E. L. Husted
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States of America
| | - Douglass G. Ivanoff
- Department
of Materials Science and Engineering, University
of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States of America
- The
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States
of America
| | - Evan M. Lloyd
- The
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States
of America
- Department
of Chemistry, University of Illinois at
Urbana—Champaign, Urbana, Illinois 61801, United States of America
| | - Julian C. Cooper
- The
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States
of America
- Department
of Chemistry, University of Illinois at
Urbana—Champaign, Urbana, Illinois 61801, United States of America
| | - Yutong Dai
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States of America
| | - Avni P. Singhal
- Department
of Materials Science and Engineering, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States of America
| | - Jeffrey S. Moore
- Department
of Materials Science and Engineering, University
of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States of America
- The
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States
of America
| | - Nancy R. Sottos
- Department
of Materials Science and Engineering, University
of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States of America
- The
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana—Champaign, Urbana, Illinois 61801, United States
of America
| | - Rafael Gomez-Bombarelli
- Department
of Materials Science and Engineering, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States of America
| | - Jeremiah A. Johnson
- Department
of Chemistry, Massachusetts Institute of
Technology, Cambridge, Massachusetts 02139, United States of America
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3
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Danahy KE, Cooper JC, Van Humbeck JF. Corrigendum: Benzylic Fluorination of Aza-Heterocycles Induced by Single-Electron Transfer to Selectfluor. Angew Chem Int Ed Engl 2023:e202305621. [PMID: 37276370 DOI: 10.1002/anie.202305621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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4
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Husted KEL, Brown CM, Shieh P, Kevlishvili I, Kristufek SL, Zafar H, Accardo JV, Cooper JC, Klausen RS, Kulik HJ, Moore JS, Sottos NR, Kalow JA, Johnson JA. Remolding and Deconstruction of Industrial Thermosets via Carboxylic Acid-Catalyzed Bifunctional Silyl Ether Exchange. J Am Chem Soc 2023; 145:1916-1923. [PMID: 36637230 DOI: 10.1021/jacs.2c11858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Convenient strategies for the deconstruction and reprocessing of thermosets could improve the circularity of these materials, but most approaches developed to date do not involve established, high-performance engineering materials. Here, we show that bifunctional silyl ether, i.e., R'O-SiR2-OR'', (BSE)-based comonomers generate covalent adaptable network analogues of the industrial thermoset polydicyclopentadiene (pDCPD) through a novel BSE exchange process facilitated by the low-cost food-safe catalyst octanoic acid. Experimental studies and density functional theory calculations suggest an exchange mechanism involving silyl ester intermediates with formation rates that strongly depend on the Si-R2 substituents. As a result, pDCPD thermosets manufactured with BSE comonomers display temperature- and time-dependent stress relaxation as a function of their substituents. Moreover, bulk remolding of pDCPD thermosets is enabled for the first time. Altogether, this work presents a new approach toward the installation of exchangeable bonds into commercial thermosets and establishes acid-catalyzed BSE exchange as a versatile addition to the toolbox of dynamic covalent chemistry.
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Affiliation(s)
- Keith E L Husted
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Christopher M Brown
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Peyton Shieh
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ilia Kevlishvili
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Samantha L Kristufek
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Hadiqa Zafar
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Joseph V Accardo
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Julian C Cooper
- Department of Chemistry, University of Illinois at Urbana Champaign, Champaign County, Illinois 61820, United States
| | - Rebekka S Klausen
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21287, United States
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jeffrey S Moore
- Department of Chemistry, University of Illinois at Urbana Champaign, Champaign County, Illinois 61820, United States.,Department of Materials Science and Engineering, University of Illinois at Urbana Champaign, Champaign County, Illinois 60208, United States
| | - Nancy R Sottos
- Department of Materials Science and Engineering, University of Illinois at Urbana Champaign, Champaign County, Illinois 60208, United States
| | - Julia A Kalow
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Jeremiah A Johnson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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5
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Ranoa DRE, Holland RL, Alnaji FG, Green KJ, Wang L, Fredrickson RL, Wang T, Wong GN, Uelmen J, Maslov S, Weiner ZJ, Tkachenko AV, Zhang H, Liu Z, Ibrahim A, Patel SJ, Paul JM, Vance NP, Gulick JG, Satheesan SP, Galvan IJ, Miller A, Grohens J, Nelson TJ, Stevens MP, Hennessy PM, Parker RC, Santos E, Brackett C, Steinman JD, Fenner MR, Dohrer K, DeLorenzo M, Wilhelm-Barr L, Brauer BR, Best-Popescu C, Durack G, Wetter N, Kranz DM, Breitbarth J, Simpson C, Pryde JA, Kaler RN, Harris C, Vance AC, Silotto JL, Johnson M, Valera EA, Anton PK, Mwilambwe L, Bryan SP, Stone DS, Young DB, Ward WE, Lantz J, Vozenilek JA, Bashir R, Moore JS, Garg M, Cooper JC, Snyder G, Lore MH, Yocum DL, Cohen NJ, Novakofski JE, Loots MJ, Ballard RL, Band M, Banks KM, Barnes JD, Bentea I, Black J, Busch J, Conte A, Conte M, Curry M, Eardley J, Edwards A, Eggett T, Fleurimont J, Foster D, Fouke BW, Gallagher N, Gastala N, Genung SA, Glueck D, Gray B, Greta A, Healy RM, Hetrick A, Holterman AA, Ismail N, Jasenof I, Kelly P, Kielbasa A, Kiesel T, Kindle LM, Lipking RL, Manabe YC, Mayes J́, McGuffin R, McHenry KG, Mirza A, Moseley J, Mostafa HH, Mumford M, Munoz K, Murray AD, Nolan M, Parikh NA, Pekosz A, Pflugmacher J, Phillips JM, Pitts C, Potter MC, Quisenberry J, Rear J, Robinson ML, Rosillo E, Rye LN, Sherwood M, Simon A, Singson JM, Skadden C, Skelton TH, Smith C, Stech M, Thomas R, Tomaszewski MA, Tyburski EA, Vanwingerden S, Vlach E, Watkins RS, Watson K, White KC, Killeen TL, Jones RJ, Cangellaris AC, Martinis SA, Vaid A, Brooke CB, Walsh JT, Elbanna A, Sullivan WC, Smith RL, Goldenfeld N, Fan TM, Hergenrother PJ, Burke MD. Mitigation of SARS-CoV-2 transmission at a large public university. Nat Commun 2022. [DOI: doi.org/10.1038/s41467-022-30833-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
AbstractIn Fall 2020, universities saw extensive transmission of SARS-CoV-2 among their populations, threatening health of the university and surrounding communities, and viability of in-person instruction. Here we report a case study at the University of Illinois at Urbana-Champaign, where a multimodal “SHIELD: Target, Test, and Tell” program, with other non-pharmaceutical interventions, was employed to keep classrooms and laboratories open. The program included epidemiological modeling and surveillance, fast/frequent testing using a novel low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD, and digital tools for communication and compliance. In Fall 2020, we performed >1,000,000 covidSHIELD tests, positivity rates remained low, we had zero COVID-19-related hospitalizations or deaths amongst our university community, and mortality in the surrounding Champaign County was reduced more than 4-fold relative to expected. This case study shows that fast/frequent testing and other interventions mitigated transmission of SARS-CoV-2 at a large public university.
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6
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Ranoa DRE, Holland RL, Alnaji FG, Green KJ, Wang L, Fredrickson RL, Wang T, Wong GN, Uelmen J, Maslov S, Weiner ZJ, Tkachenko AV, Zhang H, Liu Z, Ibrahim A, Patel SJ, Paul JM, Vance NP, Gulick JG, Satheesan SP, Galvan IJ, Miller A, Grohens J, Nelson TJ, Stevens MP, Hennessy PM, Parker RC, Santos E, Brackett C, Steinman JD, Fenner MR, Dohrer K, DeLorenzo M, Wilhelm-Barr L, Brauer BR, Best-Popescu C, Durack G, Wetter N, Kranz DM, Breitbarth J, Simpson C, Pryde JA, Kaler RN, Harris C, Vance AC, Silotto JL, Johnson M, Valera EA, Anton PK, Mwilambwe L, Bryan SP, Stone DS, Young DB, Ward WE, Lantz J, Vozenilek JA, Bashir R, Moore JS, Garg M, Cooper JC, Snyder G, Lore MH, Yocum DL, Cohen NJ, Novakofski JE, Loots MJ, Ballard RL, Band M, Banks KM, Barnes JD, Bentea I, Black J, Busch J, Conte A, Conte M, Curry M, Eardley J, Edwards A, Eggett T, Fleurimont J, Foster D, Fouke BW, Gallagher N, Gastala N, Genung SA, Glueck D, Gray B, Greta A, Healy RM, Hetrick A, Holterman AA, Ismail N, Jasenof I, Kelly P, Kielbasa A, Kiesel T, Kindle LM, Lipking RL, Manabe YC, Mayes J, McGuffin R, McHenry KG, Mirza A, Moseley J, Mostafa HH, Mumford M, Munoz K, Murray AD, Nolan M, Parikh NA, Pekosz A, Pflugmacher J, Phillips JM, Pitts C, Potter MC, Quisenberry J, Rear J, Robinson ML, Rosillo E, Rye LN, Sherwood M, Simon A, Singson JM, Skadden C, Skelton TH, Smith C, Stech M, Thomas R, Tomaszewski MA, Tyburski EA, Vanwingerden S, Vlach E, Watkins RS, Watson K, White KC, Killeen TL, Jones RJ, Cangellaris AC, Martinis SA, Vaid A, Brooke CB, Walsh JT, Elbanna A, Sullivan WC, Smith RL, Goldenfeld N, Fan TM, Hergenrother PJ, Burke MD. Mitigation of SARS-CoV-2 transmission at a large public university. Nat Commun 2022; 13:3207. [PMID: 35680861 PMCID: PMC9184485 DOI: 10.1038/s41467-022-30833-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 05/19/2022] [Indexed: 11/09/2022] Open
Abstract
In Fall 2020, universities saw extensive transmission of SARS-CoV-2 among their populations, threatening health of the university and surrounding communities, and viability of in-person instruction. Here we report a case study at the University of Illinois at Urbana-Champaign, where a multimodal “SHIELD: Target, Test, and Tell” program, with other non-pharmaceutical interventions, was employed to keep classrooms and laboratories open. The program included epidemiological modeling and surveillance, fast/frequent testing using a novel low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD, and digital tools for communication and compliance. In Fall 2020, we performed >1,000,000 covidSHIELD tests, positivity rates remained low, we had zero COVID-19-related hospitalizations or deaths amongst our university community, and mortality in the surrounding Champaign County was reduced more than 4-fold relative to expected. This case study shows that fast/frequent testing and other interventions mitigated transmission of SARS-CoV-2 at a large public university. Safely opening university campuses has been a major challenge during the COVID-19 pandemic. Here, the authors describe a program of public health measures employed at a university in the United States which, combined with other non-pharmaceutical interventions, allowed the university to stay open in fall 2020 with limited evidence of transmission.
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Affiliation(s)
- Diana Rose E Ranoa
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA.,Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Robin L Holland
- Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Fadi G Alnaji
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kelsie J Green
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Leyi Wang
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Richard L Fredrickson
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Tong Wang
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - George N Wong
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Johnny Uelmen
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Sergei Maslov
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Zachary J Weiner
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Alexei V Tkachenko
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA
| | - Hantao Zhang
- Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Zhiru Liu
- Department of Physics, Stanford University, Palo Alto, CA, USA
| | - Ahmed Ibrahim
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Sanjay J Patel
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - John M Paul
- Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Nickolas P Vance
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joseph G Gulick
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Isaac J Galvan
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Andrew Miller
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joseph Grohens
- Department of English, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Todd J Nelson
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mary P Stevens
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Robert C Parker
- McKinley Health Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | | | - Julie D Steinman
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Melvin R Fenner
- McKinley Health Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kirstin Dohrer
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Michael DeLorenzo
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Laura Wilhelm-Barr
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Catherine Best-Popescu
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Gary Durack
- Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA.,Tekmill, Champaign, IL, USA
| | | | - David M Kranz
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jessica Breitbarth
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Charlie Simpson
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Julie A Pryde
- Champaign-Urbana Public Health District, Champaign, IL, USA
| | - Robin N Kaler
- Public Affairs, College of Media, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Chris Harris
- Public Affairs, College of Media, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Allison C Vance
- Public Affairs, College of Media, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jodi L Silotto
- Public Affairs, College of Media, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mark Johnson
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Enrique Andres Valera
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Patricia K Anton
- Housing Division, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Lowa Mwilambwe
- Office of the Vice Chancellor for Student Affairs, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Stephen P Bryan
- Office of the Dean of Students, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Deborah S Stone
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Danita B Young
- Office of the Vice Chancellor for Student Affairs, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Wanda E Ward
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - John Lantz
- Office of the Dean of Students, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - John A Vozenilek
- Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Rashid Bashir
- Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jeffrey S Moore
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mayank Garg
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Julian C Cooper
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Gillian Snyder
- Interdisciplinary Health Sciences Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Michelle H Lore
- Interdisciplinary Health Sciences Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Dustin L Yocum
- Office for the Protection of Human Subjects, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Neal J Cohen
- Office of the Dean of Students, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Psychology, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jan E Novakofski
- College of Agricultural, Consumer and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Melanie J Loots
- Office of the Vice Chancellor for Research and Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Randy L Ballard
- Department of Intercollegiate Athletics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mark Band
- Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kayla M Banks
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joseph D Barnes
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Iuliana Bentea
- Department of Pathology, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Jessica Black
- Illinois Human Resources, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jeremy Busch
- Department of Intercollegiate Athletics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Abigail Conte
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Madison Conte
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Michael Curry
- Illinois Human Resources, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jennifer Eardley
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - April Edwards
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Therese Eggett
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Judes Fleurimont
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Delaney Foster
- Division of Campus Recreation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Bruce W Fouke
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA.,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Nicholas Gallagher
- Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nicole Gastala
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Scott A Genung
- Office of the Chief Info Officer, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Declan Glueck
- Illinois Human Resources, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Brittani Gray
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Andrew Greta
- University of Illinois System Office, Urbana, IL, USA
| | - Robert M Healy
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ashley Hetrick
- University Health Services, University of Wisconsin-Madison, Madison, WI, USA
| | - Arianna A Holterman
- Office of the Dean of Students, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Nahed Ismail
- Department of Pathology, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Ian Jasenof
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Patrick Kelly
- University Health Services, University of Wisconsin-Madison, Madison, WI, USA
| | - Aaron Kielbasa
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Teresa Kiesel
- University Health Services, University of Wisconsin-Madison, Madison, WI, USA
| | - Lorenzo M Kindle
- Technology Services, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Rhonda L Lipking
- Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Yukari C Manabe
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jade Mayes
- Department of Intercollegiate Athletics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Reubin McGuffin
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kenton G McHenry
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Agha Mirza
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jada Moseley
- Illinois Human Resources, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Heba H Mostafa
- Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Melody Mumford
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Kathleen Munoz
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Arika D Murray
- Illinois Human Resources, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Moira Nolan
- Office of Corporate Relations, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Nil A Parikh
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Andrew Pekosz
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Division of Infectious Diseases, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Janna Pflugmacher
- University Administration, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Janise M Phillips
- McKinley Health Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Collin Pitts
- University Health Services, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark C Potter
- Department of Family and Community Medicine, College of Medicine, University of Illinois at Chicago, Chicago, USA
| | - James Quisenberry
- Division of Student Affairs, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Janelle Rear
- Office of the Vice President for Economic Development and Innovation, University of Illinois System, Urbana, IL, USA
| | - Matthew L Robinson
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Edith Rosillo
- Library Department, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Leslie N Rye
- Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - MaryEllen Sherwood
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Anna Simon
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jamie M Singson
- Division of Student Affairs, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Carly Skadden
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Tina H Skelton
- Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Charlie Smith
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mary Stech
- McKinley Health Center, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ryan Thomas
- Office of the Chief Info Officer, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Erika A Tyburski
- Atlanta Center for Microsystems Engineered Point-of-Care Technologies, Emory University School of Medicine, Children's Healthcare of Atlanta, and Georgia Institute of Technology, Atlanta, GA, USA.,Georgia Institute of Technology, Institute for Electronics and Nanotechnology, Atlanta, GA, USA
| | - Scott Vanwingerden
- IT Service Delivery, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Evette Vlach
- Veterinary Diagnostic Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ronald S Watkins
- University of Illinois System Office, Urbana, IL, USA.,Office of the President, University of Illinois System, Urbana, IL, USA
| | - Karriem Watson
- Mile Square Health Center, University of Illinois Health, Chicago, IL, USA
| | - Karen C White
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Timothy L Killeen
- Gies College of Business, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Robert J Jones
- Office of the Chancellor, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | - Susan A Martinis
- Office of the Vice Chancellor for Research and Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Awais Vaid
- Champaign-Urbana Public Health District, Champaign, IL, USA
| | - Christopher B Brooke
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA.,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joseph T Walsh
- Library Department, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ahmed Elbanna
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - William C Sullivan
- Department of Landscape Architecture, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Rebecca L Smith
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA. .,Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Nigel Goldenfeld
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA. .,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Department of Physics, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Timothy M Fan
- Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Paul J Hergenrother
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA. .,Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Martin D Burke
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL, USA. .,Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA. .,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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7
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Minus MB, Wang H, Munoz JO, Stevens AM, Mangubat-Medina AE, Krueger MJ, Liu W, Kasembeli MM, Cooper JC, Kolosov MI, Tweardy DJ, Redell MS, Ball ZT. Targeting STAT3 anti-apoptosis pathways with organic and hybrid organic-inorganic inhibitors. Org Biomol Chem 2020; 18:3288-3296. [PMID: 32286579 PMCID: PMC7286531 DOI: 10.1039/c9ob02682g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Recurrence and drug resistance are major challenges in the treatment of acute myeloid leukemia (AML) that spur efforts to identify new clinical targets and active agents. STAT3 has emerged as a potential target in resistant AML, but inhibiting STAT3 function has proven challenging. This paper describes synthetic studies and biological assays for a naphthalene sulfonamide inhibitor class of molecules that inhibit G-CSF-induced STAT3 phosphorylation in cellulo and induce apoptosis in AML cells. We describe two different approaches to inhibitor design: first, variation of substituents on the naphthalene sulfonamide core allows improvements in anti-STAT activity and creates a more thorough understanding of anti-STAT SAR. Second, a novel approach involving hybrid sulfonamide-rhodium(ii) conjugates tests our ability to use cooperative organic-inorganic binding for drug development, and to use SAR studies to inform metal conjugate design. Both approaches have produced compounds with improved binding potency. In vivo and in cellulo experiments further demonstrate that these approaches can also lead to improved activity in living cells, and that compound 3aa slows disease progression in a xenograft model of AML.
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Affiliation(s)
- Matthew B Minus
- Prairieview A&M University, Prairie View, TX 77446, USA and Department of Chemistry, Rice University, Houston, TX 77005, USA.
| | - Haopei Wang
- Department of Chemistry, Rice University, Houston, TX 77005, USA.
| | - Jaime O Munoz
- Baylor College of Medicine, Texas Children's Cancer Center, Houston, TX 77030, USA
| | - Alexandra M Stevens
- Baylor College of Medicine, Texas Children's Cancer Center, Houston, TX 77030, USA
| | | | - Michael J Krueger
- Baylor College of Medicine, Texas Children's Cancer Center, Houston, TX 77030, USA
| | - Wei Liu
- Baylor College of Medicine, Texas Children's Cancer Center, Houston, TX 77030, USA
| | - Moses M Kasembeli
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Julian C Cooper
- Department of Chemistry, Rice University, Houston, TX 77005, USA.
| | - Mikhail I Kolosov
- Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - David J Tweardy
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA and Department of Molecule and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Michele S Redell
- Baylor College of Medicine, Texas Children's Cancer Center, Houston, TX 77030, USA
| | - Zachary T Ball
- Department of Chemistry, Rice University, Houston, TX 77005, USA.
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8
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Li G, Nykaza TV, Cooper JC, Ramirez A, Luzung MR, Radosevich AT. An Improved P III/P V═O-Catalyzed Reductive C-N Coupling of Nitroaromatics and Boronic Acids by Mechanistic Differentiation of Rate- and Product-Determining Steps. J Am Chem Soc 2020; 142:6786-6799. [PMID: 32178514 PMCID: PMC7146866 DOI: 10.1021/jacs.0c01666] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
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Experimental,
spectroscopic, and computational studies are reported
that provide an evidence-based mechanistic description of an intermolecular
reductive C–N coupling of nitroarenes and arylboronic acids
catalyzed by a redox-active main-group catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide, i.e., 1·[O]). The central observations
include the following: (1) catalytic reduction of 1·[O]
to PIII phosphetane 1 is kinetically fast
under conditions of catalysis; (2) phosphetane 1 represents
the catalytic resting state as observed by 31P NMR spectroscopy;
(3) there are no long-lived nitroarene partial-reduction intermediates
observable by 15N NMR spectroscopy; (4) the reaction is
sensitive to solvent dielectric, performing best in moderately polar
solvents (viz. cyclopentylmethyl ether); and (5) the reaction is largely
insensitive with respect to common hydrosilane reductants. On the
basis of the foregoing studies, new modified catalytic conditions
are described that expand the reaction scope and provide for mild
temperatures (T ≥ 60 °C), low catalyst
loadings (≥2 mol%), and innocuous terminal reductants (polymethylhydrosiloxane).
DFT calculations define a two-stage deoxygenation sequence for the
reductive C–N coupling. The initial deoxygenation involves
a rate-determining step that consists of a (3+1) cheletropic addition
between the nitroarene substrate and phosphetane 1; energy
decomposition techniques highlight the biphilic character of the phosphetane
in this step. Although kinetically invisible, the second deoxygenation
stage is implicated as the critical C–N product-forming event,
in which a postulated oxazaphosphirane intermediate is diverted from
arylnitrene dissociation toward heterolytic ring opening with the
arylboronic acid; the resulting dipolar intermediate evolves by antiperiplanar
1,2-migration of the organoboron residue to nitrogen, resulting in
displacement of 1·[O] and formation of the target
C–N coupling product upon in situ hydrolysis.
The method thus described constitutes a mechanistically well-defined
and operationally robust main-group complement to the current workhorse
transition-metal-based methods for catalytic intermolecular C–N
coupling.
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Affiliation(s)
- Gen Li
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Trevor V Nykaza
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Julian C Cooper
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Antonio Ramirez
- Chemical and Synthetic Development, Bristol-Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Michael R Luzung
- Chemical and Synthetic Development, Bristol-Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Alexander T Radosevich
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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9
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Affiliation(s)
- Trevor V Nykaza
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Julian C Cooper
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Alexander T Radosevich
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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10
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Nykaza TV, Cooper JC, Li G, Mahieu N, Ramirez A, Luzung MR, Radosevich AT. Intermolecular Reductive C-N Cross Coupling of Nitroarenes and Boronic Acids by P III/P V═O Catalysis. J Am Chem Soc 2018; 140:15200-15205. [PMID: 30372615 DOI: 10.1021/jacs.8b10769] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A main group-catalyzed method for the synthesis of aryl- and heteroarylamines by intermolecular C-N coupling is reported. The method employs a small-ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane) and a terminal hydrosilane reductant (phenylsilane) to drive reductive intermolecular coupling of nitro(hetero)arenes with boronic acids. Applications to the construction of both Csp2-N (from arylboronic acids) and Csp3-N bonds (from alkylboronic acids) are demonstrated; the reaction is stereospecific with respect to Csp3-N bond formation. The method constitutes a new route from readily available building blocks to valuable nitrogen-containing products with complementarity in both scope and chemoselectivity to existing catalytic C-N coupling methods.
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Affiliation(s)
- Trevor V Nykaza
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Julian C Cooper
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Gen Li
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Nolwenn Mahieu
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Antonio Ramirez
- Chemical and Synthetic Development , Bristol-Myers Squibb Company , One Squibb Drive , New Brunswick , New Jersey 08903 , United States
| | - Michael R Luzung
- Chemical and Synthetic Development , Bristol-Myers Squibb Company , One Squibb Drive , New Brunswick , New Jersey 08903 , United States
| | - Alexander T Radosevich
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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11
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Miller GJ, Stirling Y, Howarth DJ, Cooper JC, Green FR, Lane A, Humphries SE. Dietary Fat Intake and Plasma Factor VII Antigen Concentration. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1653888] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- G J Miller
- Medical Research Council Epidemiology and Medical Care Unit, Medical College of St Bartholomew ’s Hospital, London, UK
| | - Y Stirling
- Medical Research Council Epidemiology and Medical Care Unit, Medical College of St Bartholomew ’s Hospital, London, UK
| | - D J Howarth
- Medical Research Council Epidemiology and Medical Care Unit, Medical College of St Bartholomew ’s Hospital, London, UK
| | - J C Cooper
- Medical Research Council Epidemiology and Medical Care Unit, Medical College of St Bartholomew ’s Hospital, London, UK
| | - F R Green
- Division of Cardiovascular Genetics, Department of Medicine, Rayne Institute, University College London Medical School, London, UK
| | - A Lane
- Division of Cardiovascular Genetics, Department of Medicine, Rayne Institute, University College London Medical School, London, UK
| | - S E Humphries
- Division of Cardiovascular Genetics, Department of Medicine, Rayne Institute, University College London Medical School, London, UK
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12
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Danahy KE, Cooper JC, Van Humbeck JF. Benzylic Fluorination of Aza-Heterocycles Induced by Single-Electron Transfer to Selectfluor. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201801280] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Kelley E. Danahy
- Department of Chemistry; Massachusetts Institute of Technology; 77 Massachusetts Ave. Cambridge MA 02139 USA
| | - Julian C. Cooper
- Department of Chemistry; Massachusetts Institute of Technology; 77 Massachusetts Ave. Cambridge MA 02139 USA
| | - Jeffrey F. Van Humbeck
- Department of Chemistry; University of Calgary; 2500 University Drive N.W. Calgary Alberta T2N 1N4 Canada
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13
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Danahy KE, Cooper JC, Van Humbeck JF. Benzylic Fluorination of Aza-Heterocycles Induced by Single-Electron Transfer to Selectfluor. Angew Chem Int Ed Engl 2018; 57:5134-5138. [PMID: 29486098 DOI: 10.1002/anie.201801280] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Indexed: 01/20/2023]
Abstract
A selective and mild method for the benzylic fluorination of aromatic azaheterocycles with Selectfluor is described. These reactions take place by a previously unreported mechanism, in which electron transfer from the heterocyclic substrate to the electrophilic fluorinating agent Selectfluor eventually yields a benzylic radical, thus leading to the desired C-F bond formation. This mechanism enables high intra- and intermolecular selectivity for aza-heterocycles over other benzylic components with similar C-H bond-dissociation energies.
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Affiliation(s)
- Kelley E Danahy
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Julian C Cooper
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Jeffrey F Van Humbeck
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, T2N 1N4, Canada
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14
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Cooper JC, Luo C, Kameyama R, Van Humbeck JF. Combined Iron/Hydroxytriazole Dual Catalytic System for Site Selective Oxidation Adjacent to Azaheterocycles. J Am Chem Soc 2018; 140:1243-1246. [PMID: 29345461 DOI: 10.1021/jacs.7b12864] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
This report details a new method for site-selective methylene oxidation adjacent to azaheterocycles. A dual catalysis approach, utilizing both an iron Lewis acid and an organic hydroxylamine catalyst, proved highly effective. We demonstrate that this method provides complementary selectivity to other known catalytic approaches and represents an improvement over current heterocycle-selective reactions that rely on stoichiometric activation.
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Affiliation(s)
- Julian C Cooper
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Chaosheng Luo
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Ryohei Kameyama
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan
| | - Jeffrey F Van Humbeck
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
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15
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Purwar B, Ismail KM, Turner N, Farrell A, Verzune M, Annappa M, Smith I, El-Gizawy Z, Cooper JC. General or Spinal Anaesthetic for Vaginal Surgery in Pelvic Floor Disorders (GOSSIP): a feasibility randomised controlled trial. Int Urogynecol J 2015; 26:1171-8. [PMID: 25792351 DOI: 10.1007/s00192-015-2670-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 02/24/2015] [Indexed: 11/30/2022]
Abstract
INTRODUCTION AND HYPOTHESIS Spinal anaesthesia (SA) and general anaesthesia (GA) are widely used techniques for vaginal surgery for pelvic floor disorders with inconclusive evidence of the superiority of either. We conducted a randomised controlled trial (RCT) to assess the feasibility of a full scale RCT aiming to examine the effect of anaesthetic mode for vaginal surgery on operative, patient reported and length of hospital stay (LOHS) outcomes. METHODS Patients undergoing vaginal surgery, recruited through a urogynaecology service in a University teaching hospital, were randomised to receive either GA or SA. Patients were followed up for 12 weeks postoperatively. Pain was measured on a visual analogue scale; nausea was assessed with a four-point verbal rating scale. Patient's subjective perception of treatment outcome, quality of life (QoL) and functional outcomes were assessed using the International Consultation on Incontinence Modular Questionnaire (ICIQ) on vaginal symptoms and the SF-36 questionnaire. RESULTS Sixty women were randomised, 29 to GA and 31 to SA. The groups were similar in terms of age and type of vaginal surgery performed. No statistically significant differences were noted between the groups with regard to pain, nausea, quality of life (QoL), functional outcomes as well as length of stay in the postoperative recovery room, use of analgesia postoperatively and LOHS. CONCLUSION This study has demonstrated that a full RCT is feasible and should focus on the length of hospital stay in a subgroup of patients undergoing vaginal surgery where SA may help to facilitate enhanced recovery or day surgery.
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Affiliation(s)
- B Purwar
- Department of Obstetrics and Gynaecology, Royal Stoke University Hospital, Newcastle Road, Stoke-on-Trent, Staffordshire, ST4 6QG, UK
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16
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Coughlin JM, Kundu R, Cooper JC, Ball ZT. Inhibiting prolyl isomerase activity by hybrid organic–inorganic molecules containing rhodium(II) fragments. Bioorg Med Chem Lett 2014; 24:5203-6. [DOI: 10.1016/j.bmcl.2014.09.068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/11/2014] [Accepted: 09/24/2014] [Indexed: 02/06/2023]
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17
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Abstract
OBJECTIVE Safe midwifery staffing levels on delivery suites is a priority area for any maternity service. Escalation policies are tools that provide an operational response to emergency pressures. The aim of this study was to assess the feasibility of using a scoring system to contemporaneously assess the required staffing level based on demand and use this to determine delivery suite escalation level and utilise the information generated regarding clinical activity (Demand) and staffing levels (Capacity) to generate unit-specific calculation for the actual number of midwifery staff required. SETTING A maternity unit of a university-affiliated tertiary referral hospital. DESIGN Over a 12-month period, specifically designed scoring sheets were completed by delivery suite shift co-ordinators four times a day (04:00, 10:00, 16:00 and 22:00). Based on the dependency score (Demand) and the number of midwifery staff available (Capacity), an escalation level was determined for each shift. The 80th centile of the demand was used to determine optimal capacity. RESULTS A total of 1160 scoring sheets were completed. Average staff number throughout the year on any shift was 7 (range 3-11). Average dependency score was 7 (range 1-14). The 80th centile for demand was calculated to be 11. CONCLUSIONS This study stresses the importance and usefulness of a simple tool that can be used to determine the level of escalation on delivery suite based on an objective scoring system and can also be used to determine the appropriate staffing on delivery suite.
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Affiliation(s)
- I Siddiqui
- University Hospital of North Staffordshire NHS Trust, Stoke, UK
| | - B Whittingham
- University Hospital of North Staffordshire NHS Trust, Stoke, UK
| | - K Meadowcroft
- University Hospital of North Staffordshire NHS Trust, Stoke, UK
| | - M Richardson
- University Hospital of North Staffordshire NHS Trust, Stoke, UK
| | - J C Cooper
- University Hospital of North Staffordshire NHS Trust, Stoke, UK
| | - J Belcher
- Department of Primary Care Sciences, Arthritis Research UK Primary Care Centre, Keele University, Staffordshire, Keele, UK
| | - E Morris
- Norfolk and Norwich University Hospital NHS Foundation Trust, Norwich, UK
| | - K M K Ismail
- College of Medical & Dental Sciences, Birmingham centre for Women's and Children's Health, School of Clinical & Experimental Medicine, University of Birmingham, Birmingham, UK Birmingham Women's NHS Foundation Trust, Birmingham, UK
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Siraj N, Benerjee S, Cooper JC, Ismail KMK. Prioritisation of teaching topics in obstetrics and gynaecology: a Delphi survey of postgraduate trainees. J OBSTET GYNAECOL 2011; 31:692-4. [PMID: 22085055 DOI: 10.3109/01443615.2011.590909] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Topics for theoretical teaching during the obstetrics and gynaecology specialty training programme are often chosen by tutors, with little input from the trainees. However, it is important to actively involve adults in their learning process to maintain their learning ownership and motivation. The Delphi methodology is a generic social science technique used to aggregate views and opinions of experts, the community and service users. In this study, we conducted a two generational Delphi study to achieve consensus between a group of trainees in obstetrics and gynaecology, regarding what they considered important topics for inclusion in their protected teaching programme. A total of 25 trainees from one deanery, participated in this study. We were able to produce a list of 26 topics in obstetrics and 30 in gynaecology, prioritised according to their importance for inclusion in the specialty protected teaching programme, as viewed by these trainees.
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Affiliation(s)
- N Siraj
- Maternity Centre, University Hospital of North Staffordshire, Stoke-on-Trent, Staff ordshire ST4 6QG, UK
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Ho MW, Boyle MA, Cooper JC, Dodd MD, Richardson D. Surgical complications of segmental Le Fort I osteotomy. Br J Oral Maxillofac Surg 2010; 49:562-6. [PMID: 20965624 DOI: 10.1016/j.bjoms.2010.09.018] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 09/23/2010] [Indexed: 10/18/2022]
Abstract
Segmental maxillary osteotomy is a useful adjunct in orthognathic surgery for the correction of vertical and transverse maxillary deformities, but we know of few published reports that document complications. We evaluated the complication rates associated with segmental maxillary surgery in our unit by retrospective review of medical records, radiographs, and study models of 85 consecutive patients (mean age 23.3 years, range 14-51; male:female ratio 1:2) treated from 1995 to 2009. Types of deformity were anterior open bite (n=30, 35%), transverse maxillary deficiency (n=24, 28%), anterior open bite with transverse maxillary deficiency (n=28, 33%), and anterior vertical maxillary excess (n=3, 4%). There were 70 tripartite (82%), 13 bipartite (15%), and two quadripartite (2%) maxillas. Twenty-one patients (25%) had bone grafts. Fixation was done using titanium miniplates in 80 patients (94%), and titanium miniplates and resorbable plates in five (6%). The overall complication rate was 27%. Three patients (4%) had devitalisation of teeth, three (4%) developed minor periodontal defects, and one had tooth loss. Eight patients (9%) had plates removed, and two patients developed persistent postoperative palatal fistula. There was no segmental loss of bone or teeth. Our results show that complications in this cohort were relatively low, and that segmental maxillary surgery is safe as an adjunct in carefully selected cases.
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Affiliation(s)
- M W Ho
- Regional Maxillofacial Unit, University Hospital Aintree, Liverpool L9 7AL, United Kingdom.
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Lambert R, Brownlie PD, Woodcock SC, Louie GV, Cooper JC, Warren MJ, Jordan PM, Blundell TL, Wood SP. Structural studies on porphobilinogen deaminase. Ciba Found Symp 2007; 180:97-104; discussion 105-10. [PMID: 7842864 DOI: 10.1002/9780470514535.ch6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The X-ray crystallographic analysis of porphobilinogen deaminase (hydroxymethylbilane synthase, EC 4.3.1.8) shows the polypeptide chain folded into three domains, (1) N-terminal, (2) central and (3) C-terminal, of approximately equal size. Domains 1 and 2 have a similar overall topology, a modified doubly wound parallel beta-sheet. Domain 3 is an open-faced three-stranded antiparallel beta-sheet, with one face covered by three alpha-helices. The active site is located between domains 1 and 2. The dipyrromethane cofactor linked to cysteine 242 protrudes from domain 3 into the mouth of the cleft. Flexible segments between domains 1 and 2 are thought to have a role in a hinge mechanism, facilitating conformational changes. The cleft is lined with positively charged, highly conserved, arginine residues which form ion pairs with the acidic side chains of the cofactor. Aspartic acid 84 has been identified as a critical catalytic residue both by its proximity to the cofactor pyrrole ring nitrogen and by structural and kinetic studies of the Asp-84-->Glu mutant protein. The active site arginine residues have been altered by site-directed mutagenesis to histidine residues. The mutant proteins have been studied crystallographically in order to reconcile the functional changes in the polymerization reaction with structural changes in the enzyme.
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Affiliation(s)
- R Lambert
- Department of Crystallography, Birkbeck College, London, UK
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Wyse CA, Skeldon K, Hotchkiss JW, Gibson G, Yam PS, Christley RM, Preston T, Cumming DRS, Padgett M, Cooper JC, Love S. Effects of changes to the stable environment on the exhalation of ethane, carbon monoxide and hydrogen peroxide by horses with respiratory inflammation. Vet Rec 2005; 157:408-12. [PMID: 16199775 DOI: 10.1136/vr.157.14.408] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The aim of this study was to assess the effects of changes to the stable environment on exhaled markers of respiratory inflammation in six horses with clinical histories of recurrent airway obstruction. The horses were maintained for two weeks under conventional stable management (straw bedding and hay) and for two weeks on a reduced-dust regimen (paper bedding and ensiled grass), in a crossover study design. Exhaled ethane and carbon monoxide (CO) and exhaled breath condensate hydrogen peroxide (H(2)O(2)) were measured every three days under each regimen. The presence of clinical signs of airway inflammation (nasal discharge and cough) was monitored daily. The reduced-dust regimen was associated with fewer clinical signs of airway inflammation than the conventional regimen. Exhaled ethane and CO were significantly lower on the reduced-dust regimen and these markers were correlated with clinical signs of respiratory inflammation, but exhaled H(2)O(2) was not affected by the management regimen.
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Affiliation(s)
- C A Wyse
- Division of Companion Animal Sciences, Institute of Comparative Medicine, University of Glasgow Veterinary School, Bearsden, Glasgow G61 1QH, Scotland, UK
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Balasubramanian SP, Cooper JC. Diagnostic peritoneal lavage — an obituary ( Br J Surg 2005; 92: 517–518). Br J Surg 2005; 92:1177-8. [PMID: 16106475 DOI: 10.1002/bjs.5162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Noonan syndrome is characterised by short stature, unusual facies, congenital heart disease, chest deformity and mild mental retardation. It may be sporadic or inherited as an autosomal dominant trait and occurs between one in 1000-2500. Cherubism is a giant cell lesion of the jaws thought to be transmitted as an autosomal dominant trait. It is usually recognised by age two to four years, follows a variable course, and is not known to be related to other genetic disorders. The purpose of this article is to report a case of multiple giant cell lesions of the mandible that occurred in a patient with phenotypic features of Noonan syndrome. The emerging relationship between these cherubism-like findings and Noonan syndrome will be discussed.
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Affiliation(s)
- S M G Lee
- Royal Liverpool Children's Hospital, Liverpool, UK.
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Gomes-Marcondes MCC, Ventrucci G, Toledo MT, Cury L, Cooper JC. A leucine-supplemented diet improved protein content of skeletal muscle in young tumor-bearing rats. Braz J Med Biol Res 2003; 36:1589-94. [PMID: 14576914 DOI: 10.1590/s0100-879x2003001100017] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Cancer cachexia induces host protein wastage but the mechanisms are poorly understood. Branched-chain amino acids play a regulatory role in the modulation of both protein synthesis and degradation in host tissues. Leucine, an important amino acid in skeletal muscle, is higher oxidized in tumor-bearing animals. A leucine-supplemented diet was used to analyze the effects of Walker 256 tumor growth on body composition in young weanling Wistar rats divided into two main dietary groups: normal diet (N, 18% protein) and leucine-rich diet (L, 15% protein plus 3% leucine), which were further subdivided into control (N or L) or tumor-bearing (W or LW) subgroups. After 12 days, the animals were sacrificed and their carcass analyzed. The tumor-bearing groups showed a decrease in body weight and fat content. Lean carcass mass was lower in the W and LW groups (W = 19.9 0.6, LW = 23.1 1.0 g vs N = 29.4 1.3, L = 28.1 1.9 g, P < 0.05). Tumor weight was similar in both tumor-bearing groups fed either diet. Western blot analysis showed that myosin protein content in gastrocnemius muscle was reduced in tumor-bearing animals (W = 0.234 0.033 vs LW = 0.598 0.036, N = 0.623 0.062, L = 0.697 0.065 arbitrary intensity, P < 0.05). Despite accelerated tumor growth, LW animals exhibited a smaller reduction in lean carcass mass and muscle myosin maintenance, suggesting that excess leucine in the diet could counteract, at least in part, the high host protein wasting in weanling tumor-bearing rats.
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Affiliation(s)
- M C C Gomes-Marcondes
- Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil.
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Affiliation(s)
- K A Patel
- Department of Obstetrics and Gynaecology, Rotherham General Hospital, UK.
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Affiliation(s)
- M De
- Department of Obstetrics and Gynaecology, Countess of Chester Hospital, The Countess of Chester Health Park, UK
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Patel KA, Cooper JC. The 'Tellytubby tummy'. A novel technique for laparostomy management. Ann R Coll Surg Engl 2002; 84:367; author reply 368. [PMID: 12398133 PMCID: PMC2504183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
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Gomes-Marcondes MCC, Smith HJ, Cooper JC, Tisdale MJ. Development of an in-vitro model system to investigate the mechanism of muscle protein catabolism induced by proteolysis-inducing factor. Br J Cancer 2002; 86:1628-33. [PMID: 12085214 PMCID: PMC2746596 DOI: 10.1038/sj.bjc.6600236] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2001] [Revised: 02/13/2002] [Accepted: 02/13/2002] [Indexed: 11/12/2022] Open
Abstract
The mechanism of muscle protein catabolism induced by proteolysis-inducing factor, produced by cachexia-inducing murine and human tumours has been studied in vitro using C(2)C(12) myoblasts and myotubes. In both myoblasts and myotubes protein degradation was enhanced by proteolysis-inducing factor after 24 h incubation. In myoblasts this followed a bell-shaped dose-response curve with maximal effects at a proteolysis-inducing factor concentration between 2 and 4 nM, while in myotubes increased protein degradation was seen at all concentrations of proteolysis-inducing factor up to 10 nM, again with a maximum of 4 nM proteolysis-inducing factor. Protein degradation induced by proteolysis-inducing factor was completely attenuated in the presence of cycloheximide (1 microM), suggesting a requirement for new protein synthesis. In both myoblasts and myotubes protein degradation was accompanied by an increased expression of the alpha-type subunits of the 20S proteasome as well as functional activity of the proteasome, as determined by the 'chymotrypsin-like' enzyme activity. There was also an increased expression of the 19S regulatory complex as well as the ubiquitin-conjugating enzyme (E2(14k)), and in myotubes a decrease in myosin expression was seen with increasing concentrations of proteolysis-inducing factor. These results show that proteolysis-inducing factor co-ordinately upregulates both ubiquitin conjugation and proteasome activity in both myoblasts and myotubes and may play an important role in the muscle wasting seen in cancer cachexia.
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Affiliation(s)
- M C C Gomes-Marcondes
- Department of Physiology and Biophysics, University of Campinas, UNICAMP, SP, Brazil 13083-970.
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Cooper JC, Hughes S, Ben-Smith A, Savage COS, Winer JB. T cell recognition of a non-protein antigen preparation of Campylobacter jejuni in patients with Guillain-Barré syndrome. J Neurol Neurosurg Psychiatry 2002; 72:413-4. [PMID: 11861714 PMCID: PMC1737765 DOI: 10.1136/jnnp.72.3.413] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
CR-EAE is a Th1-mediated inflammatory autoimmune demyelinating disease of the CNS and serves as a model of human multiple sclerosis. Our previous studies have shown the protective effect of orally administered lisofylline in the prevention of active and passively induced acute EAE. In our present studies we have examined the efficacy and mechanism of action of lisofylline on CR-EAE. Lisofylline decreased the number and severity of paralytic attacks in mice with relapsing EAE. The reduction of clinical disease correlated with decreased levels of mRNA levels of IFN-gamma but not of mRNA levels of IL-12. These studies suggest that lisofylline may be an effective therapeutic for established Th1 mediated autoimmune disease and that it acts by blocking IL-12R signaling and not IL-12 production in vivo.
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Affiliation(s)
- C Du
- Department of Neurology, Multiple Sclerosis Research Center, Room 1222, Vanderbilt Stallworth Rehabilitation Hospital, Vanderbilt University Medical Center, 2201 Capers Ave, Nashville, TN 37212, USA
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Cooper JC, Ben-Smith A, Savage CO, Winer JB. Unusual T cell receptor phenotype V gene usage of gamma delta T cells in a line derived from the peripheral nerve of a patient with Guillain-Barré syndrome. J Neurol Neurosurg Psychiatry 2000; 69:522-4. [PMID: 10990516 PMCID: PMC1737144 DOI: 10.1136/jnnp.69.4.522] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Guillain-Barré syndrome is considered to be an immune mediated disorder but the relative role of T cells and antibodies in its pathogenesis is unclear. As gut infection with Campylobacter jejuni is the most common antecedent infection it is possible that gut derived T lymphocytes might play a part in the development of the syndrome. The T cell receptor phenotype (TCR) of a nerve gamma delta T cell line obtained from a sural nerve biopsy taken from a patient with a demyelinating form of GBS was determined using polymerase chain reaction (PCR) and flow cytometry (FACS). This TCR was compared with the phenotype preferentially expressed in the peripheral blood of the same patient. The T cell nerve line was found to express V gamma 8/delta 1 which represents an unusual T cell subset normally found on lymphocytes resident in epithelial tissue such as the gut. The peripheral blood gamma delta T lymphocytes from the patient were of the V gamma 9/delta 2 subset, which is the phenotype predominantly expressed in the peripheral blood of healthy subjects. In conclusion, the presence of this unusual population of V gamma 8/delta 1(+) lymphocytes in nerve would be consistent with a pathogenetic role for gut associated lymphocytes in the pathogenesis of Guillain-Barré syndrome associated with C jejuni.
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Affiliation(s)
- J C Cooper
- Birmingham Centre for Immune Regulation, Division of Medical Sciences, The Medical School, University of Birmingham, Edgbaston, Birmingham, UK
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Larson AA, Kovacs KJ, Cooper JC, Kitto KF. Transient changes in the synthesis of nitric oxide result in long-term as well as short-term changes in acetic acid-induced writhing in mice. Pain 2000; 86:103-11. [PMID: 10779667 DOI: 10.1016/s0304-3959(00)00236-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A single injection of nitric oxide (NO) synthase (NOS) inhibitors prevents the development of persistent hyperalgesia induced by various manipulations, suggesting that NO precipitates long-term changes in nociception. We examined the possibility that inhibition of NOS may also be sufficient to produce long-term decreases in nociceptive assays, such as writhing, that are known to be sensitive to the short-term effects of NOS inhibitors. We characterized short- and long-term effects of NOS inhibitors, N(omega)-nitro-L-arginine (L-NAME) or 7-nitro indazole (7-NI) injected intrathecally (i.t.) in mice on acetic acid-induced writhing. Doses of L-NAME that had no effect on hot plate or tail flick latencies inhibited writhing (0. 01-30 nmol) as well as spinal nNOS activity (5 and 100 nmol) when injected i.t. 60-90 min before testing. Anti-nociception was not mimicked by D-NAME but was prevented by co-administration with the NO precursor, L-arginine. Injection i.t. of 7-NI (30 min), a selective inhibitor of neuronal NOS (nNOS), inhibited NOS activity in the spinal cord and produced anti-nociception, confirming that writhing is sensitive to inhibition of nNOS. Although the acute action of both NOS inhibitors dissipated completely by 3-6 h, a delayed and prolonged inhibition of writhing was again observed 24 h after L-NAME (5-100 nmol), a time when spinal NOS activity was no longer inhibited by L-NAME (5 and 100 nmol) or 7-NI (25 nmol). This novel effect appears to be initiated by the transient inhibition of nNOS as delayed anti-nociception was mimicked by 7-NI at doses (10-100 nmol) that no longer inhibited spinal nNOS (25 nmol) at 24 h. Co-administration with L-arginine prevented the delayed (24 h) anti-nociceptive effects of L-NAME (30 nmol). L-Arginine (30 and 100 nmol) was without effect on nociception when administered alone 60 min or 24 h prior to testing. Together these data indicate that brief changes in the activity of nNOS induce both long- as well as short-term changes in nociception.
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Affiliation(s)
- A A Larson
- Graduate Program in Neuroscience, Department of Veterinary Pathobiology, University of Minnesota, St. Paul 55108, USA.
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Cooper JC, Fernandez N, Joly E, Dealtry GB. Regulation of major histocompatibility complex and TAP gene products in preimplantation mouse stage embryos. Am J Reprod Immunol 1998; 40:165-71. [PMID: 9764360 DOI: 10.1111/j.1600-0897.1998.tb00408.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
PROBLEM To determine the ontogeny of major histocompatibility complex (MHC) expression and TAP products in mouse embryos. METHOD OF STUDY mRNAs encoding MHC and associated molecules were identified by reverse transcriptase-polymerase chain reaction, and the protein products were localized by confocal microscopy. RESULTS mRNAs encoding class Ia (H-2Db) and class Ib (Q7/9) were present in one-cell embryos, whereas beta 2-microglobulin (beta 2-m) transcripts were not detected until the two-cell stage. Transporter TAP1, but not TAP2, transcripts were detected only in blastocysts. H-2 class Ia (classical) protein was detected on the surface of two-cell embryos, H-2 class Ib (nonclassical) protein was detected on one-cell embryos, and beta 2-m transcripts were detected on eight-cell embryos; TAP1 protein was present at low levels in the cytoplasm from the one-cell stage onward, increasing in expression in blastocysts. CONCLUSIONS In mice, MHC class I mRNAs encoding the heavy chain of H-2- and Q7/9-encoding Qa2 molecules are synthesized soon after conception prior to implantation. Similarly, the nonpolymorphic MHC class I-associated molecule beta 2-m also is expressed before implantation. TAP1, but not TAP2, is first detected at the blastocyst stage, thus preceding the onset of TAP2 in embryonic development.
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Affiliation(s)
- J C Cooper
- Department of Biological Sciences, University of Essex, Colchester, UK
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Sidebottom AJ, Cooper JC. Treatment for trigeminal neuralgia. Editorial did not consider a multidisciplinary team approach. BMJ 1997; 314:520. [PMID: 9056827 PMCID: PMC2126006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Sharkey AM, Cooper JC, Balmforth JR, McLaren J, Clark DE, Charnock-Jones DS, Morris NH, Smith SK. Maternal plasma levels of vascular endothelial growth factor in normotensive pregnancies and in pregnancies complicated by pre-eclampsia. Eur J Clin Invest 1996; 26:1182-5. [PMID: 9013097 DOI: 10.1046/j.1365-2362.1996.830605.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have measured the level of vascular endothelial growth factor (VEGF) in maternal plasma during normotensive pregnancy and in pregnancies complicated by pre-eclampsia. VEGF was measured using a competitive enzyme immunoassay. Plasma VEGF was significantly elevated (P < 0.0001) in the pre-eclamptic group (median value 32.7 ng mL-1, range 10.3-64.0), compared with the normotensive group (median value 11.7 ng mL-1, range 6.3-24.3). VEGF is a potent regulator of endothelial cell function. The increased level found in women with pre-eclampsia indicates that VEGF may be involved in the maternal endothelial cell dysfunction associated with this condition. An increase in VEGF, a potent regulator of microvascular permeability, may also contribute to the extravasation of plasma proteins and the subsequent development of proteinuria, both characteristic features of pre-eclampsia.
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Affiliation(s)
- A M Sharkey
- Department of Obstetrics and Gynaecology, University of Cambridge, Rosie Maternity Hospital, UK
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Cooper JC, Sharkey AM, Charnock-Jones DS, Palmer CR, Smith SK. VEGF mRNA levels in placentae from pregnancies complicated by pre-eclampsia. Br J Obstet Gynaecol 1996; 103:1191-6. [PMID: 8968234 DOI: 10.1111/j.1471-0528.1996.tb09627.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To measure the mRNA levels of vascular endothelial growth factor and its receptor in the placenta following delivery after uncomplicated pregnancy and after pregnancies complicated by pre-eclampsia. SETTING Rosie Maternity Hospital, Cambridge. MATERIAL Placental biopsies were obtained following delivery by caesarean section in 23 cases of pregnancy presenting at a range of gestational ages with pre-eclampsia. These were compared with biopsies from 20 appropriately matched women with uncomplicated pregnancies. MAIN OUTCOME MEASURE mRNA levels of vascular endothelial growth factor (VEGF) and its receptor the fins-like tyrosine kinase (flt), were quantified in total RNA isolated from placental biopsies using the RNAse protection assay. The amount of RNA was compared with that of the housekeeping gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH), used as a standard. Results were expressed as arbitrary optical density units of VEGF/GAPDH and flt/GAPDH. RESULTS In both control and pre-eclamptic women regression analysis showed that the level of mRNA encoding VEGF declined significantly with gestational age (P < 0.0001). However, levels of VEGF mRNA were significantly lower in the pre-eclamptic women compared with the control women (P < 0.023). CONCLUSIONS This study provides evidence of an abnormality of growth factor expression in the placenta during pregnancies complicated by pre-eclampsia. Such placentae exhibit deficient growth and differentiation of terminal villi and reduced fetal capillary branching and reduced levels of VEGF could well account for these morphometric changes. This finding provides a molecular explanation for this abnormal placental development and points to VEGF as a factor in the aetiology of pre-eclampsia and its complications.
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Affiliation(s)
- J C Cooper
- Department of Obstetrics and Gynaecology, University of Cambridge, Rosie Maternity Hospital, Cambridge, UK
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Wetzka B, Charnock-Jones DS, Viville B, Cooper JC, Nüsing R, Zahradnik HP, Smith SK. Expression of prostacyclin and thromboxane synthases in placenta and placental bed after pre-eclamptic pregnancies. Placenta 1996; 17:573-81. [PMID: 8916205 DOI: 10.1016/s0143-4004(96)80074-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Prostacyclin and thromboxane are potent antagonistic regulators of vascular tone and platelet aggregation. In pre-eclampsia, the ratio of their metabolites is decreased. Little is known about the local regulation of intrauterine prostacyclin and thromboxane production in this condition. Placenta and placental bed biopsies were obtained from uncomplicated and pre-eclamptic pregnancies. Prostacyclin synthase (PCS) and thromboxane synthase (TXS) and their mRNA's were localized by immunohistochemistry using monoclonal antibodies and in situ hybridization. Protein and mRNA levels were quantified by immunoblot and RNase protection assay. PCS-like immunoreactivity was found in endothelial cells and leiomyocytes, whereas fetal and maternal macrophages showed positive staining for TXS. Their mRNA was localized to trophoblast and endothelium, and TXS mRNA could also be detected in macrophages. Quantitative analysis showed no significant difference in intrauterine protein or mRNA expression after pre-eclampsia. The prostacyclin and thromboxane production seems to be compartmentalized within the uteroplacental unit. The expression of their synthesizing enzymes might be regulated post-transcriptionally. Additional regulation of prostaglandin production could be metabolically or on the substrate level and requires further elucidation.
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Affiliation(s)
- B Wetzka
- Department of Obstetrics and Gynaecology, University of Cambridge, UK
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Cooper JC, Gutbrod O, Witzemann V, Methfessel C. Pharmacology of the nicotinic acetylcholine receptor from fetal rat muscle expressed in Xenopus oocytes. Eur J Pharmacol 1996; 309:287-98. [PMID: 8874153 DOI: 10.1016/0014-2999(96)00294-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The fetal rat muscle nicotinic acetylcholine receptor was expressed in Xenopus oocytes. Using the voltage-clamp technique, the response to a range of agonists was measured, listed in order of (decreasing) activity efficacy: anatoxin > or = epibatidine > acetylcholine > DMPP (1,1-dimethyl-4-phenylpiperazinium) > > cytisine > pyrantel > nicotine > coniine > tubocurare > lobeline. The agonist responses were compared with the steric and electrostatic properties of the molecules, using molecular modelling. Single-channel current were measured in outside-out patches for acetylcholine, nicotine, cytisine, anatoxin and epibatidine. The conductance of the single channels was independent of the type of agonist. The mean open times were characteristic of the agonist applied. Tubocurare, better known for its antagonist properties, was also a partial agonist. Single-channel currents were also observed for tubocurare, and for methyllycaconitine in patches with a very high density of the muscle nicotinic acetylcholine receptor, and these were blocked by alpha-bungarotoxin. The agonist properties of physostigmine, galanthamine and their methyl derivatives were also investigated. The conductance of the channels observed in outside-out patches was similar to that obtained for the classical agonists. The single-channel currents observed for physostigmine, galanthamine and their methyl derivatives were blocked by alpha-bungarotoxin, methyllycaconitine and mecamylamine, in contrast to previously reported studies on neuronal and adult muscle nicotinic acetylcholine receptors.
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Affiliation(s)
- J C Cooper
- Zentrale Forschung, Bayer AG, Leverkusen, Germany
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Cooper JC, Sharkey AM, McLaren J, Charnock-Jones DS, Smith SK. Localization of vascular endothelial growth factor and its receptor, flt, in human placenta and decidua by immunohistochemistry. J Reprod Fertil 1995; 105:205-13. [PMID: 8568762 DOI: 10.1530/jrf.0.1050205] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Vascular endothelial growth factor is a secreted angiogenic growth factor the mRNA of which is present in the placenta. The mRNA encoding the vascular endothelial growth factor receptor, flt, has also been demonstrated in placenta, with trophoblast appearing to be a novel site of flt expression. We investigated the expression of both vascular endothelial growth factor and flt-like immunoreactivity in first trimester and term placentae. In the first trimester, vascular endothelial growth factor immunoreactivity was localized to placental macrophages (Hofbauer cells), and in decidua, to glandular epithelium and maternal macrophages. In the term placenta, vascular endothelial growth factor immunoreactivity was present in extravillous trophoblast and in extracellular material. Flt immunoreactivity was demonstrated on extravillous trophoblast in first trimester and term, and on Hofbauer cells within placental villi. This complex pattern of both vascular endothelial growth factor and flt-like immunoreactivity suggests that vascular endothelial growth factor may be involved not only in the regulation of placental angiogenesis, but also in trophoblast invasion.
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Affiliation(s)
- J C Cooper
- Department of Obstetrics and Gynaecology, University of Cambridge, Rosie Maternity Hospital, UK
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Storch A, Schrattenholz A, Cooper JC, Abdel Ghani EM, Gutbrod O, Weber KH, Reinhardt S, Lobron C, Hermsen B, Soskiç V. Physostigmine, galanthamine and codeine act as 'noncompetitive nicotinic receptor agonists' on clonal rat pheochromocytoma cells. Eur J Pharmacol 1995; 290:207-19. [PMID: 7589215 DOI: 10.1016/0922-4106(95)00080-1] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The acetylcholine esterase inhibitor (-)-physostigmine has been shown to act as agonist on nicotinic acetylcholine receptors from muscle and brain, by binding to sites on the alpha-polypeptide that are distinct from those for the natural transmitter acetylcholine (Schröder et al., 1994). In the present report we show that (-)-physostigmine, galanthamine, and the morphine derivative codeine activate single-channel currents in outside-out patches excised from clonal rat pheochromocytoma (PC12) cells. Although several lines of evidence demonstrate that the three alkaloids act on the same channels as acetylcholine, the competitive nicotinic antagonist methyllycaconitine only inhibited channel activation by acetylcholine but not by (-)-physostigmine, galanthamine or codeine. In contrast, the monoclonal antibody FK1, which competitively inhibits (-)-physostigmine binding to nicotinic acetylcholine receptors, did not affect channel activation by acetylcholine but inhibited activation by (-)-physostigmine, galanthamine and codeine. The three alkaloids therefore act via binding sites distinct from those for acetylcholine, in a 'noncompetitive' fashion. The potency of (-)-physostigmine and related compounds to act as a noncompetitive agonist is unrelated to the level of acetylcholine esterase inhibition induced by these drugs. (-)-Physostigmine, galanthamine and codeine do not evoke sizable whole-cell currents, which is due to the combined effects of low open-channel probability, slow onset and slow inactivation of response. In contrast, they sensitize PC12 cell nicotinic receptors in their submaximal response to acetylcholine. While the abundance of nicotinic acetylcholine receptor isoforms expressed in PC12 cells excludes identification of specific nicotinic acetylcholine receptor subtypes that interact with noncompetitive agonists, the identical patterns of single-channel current amplitudes observed with acetylcholine and with noncompetitive agonists suggested that all PC12 cell nicotinic acetylcholine receptor subtypes that respond to acetylcholine also respond to noncompetitive agonist. The action of noncompetitive agonists therefore seems to be highly conserved between nicotinic acetylcholine receptor subtypes, in agreement with the high level of structural conservation in the sequence region harboring major elements of this site.
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Affiliation(s)
- A Storch
- Laboratory of Molecular Neurobiology, Johannes Gutenberg University Medical School, Mainz, Germany
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Cooper JC, Sharkey AM. Growth factors in pregnancy. Indian J Physiol Pharmacol 1995; 39:197-203. [PMID: 8550110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The role of growth factors in pregnancy is a rapidly expanding subject. With the advent of molecular biological techniques more and more detailed information is available to the researcher. This review does not attempt to be exhaustive in its coverage of growth factors in pregnancy, rather it tries to give a brief taste of the possible roles that they may play in pregnancy by considering three specific factors, leukaemia inhibitory factor, colony stimulating factor-1 and vascular endothelial growth factor.
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Affiliation(s)
- J C Cooper
- University of Cambridge, Department of Obstetrics & Gynaecology, Rosie Maternity Hospital, U.K
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Miller GJ, Stirling Y, Howarth DJ, Cooper JC, Green FR, Lane A, Humphries S. Dietary fat intake and plasma factor VII antigen concentration. Thromb Haemost 1995; 73:893. [PMID: 7482423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Cooper JC, Suver JD. The costs of quality. J Health Adm Educ 1995; 13:155-63. [PMID: 10140255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Affiliation(s)
- J C Cooper
- College of Allied Health Professions, University of Kentucky, Lexington 40506
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Suver JD, Cooper JC. Revenue enhancement and cost analysis. Healthc Exec 1994; 9:41. [PMID: 10135158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Cooper JC. The effect of placental syncytiotrophoblast microvillous membranes from normal and pre-eclamptic women on the growth of endothelial cells in vitro. Br J Obstet Gynaecol 1994; 101:559. [PMID: 8018654 DOI: 10.1111/j.1471-0528.1994.tb13171.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Cooper JC. Health and Nutrition Examination Survey of 1971-75: Part II. Tinnitus, subjective hearing loss, and well-being. J Am Acad Audiol 1994; 5:37-43. [PMID: 8155893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The Health and Nutrition Examination Survey of 1971-75 contains valuable information because it provides unbiased estimates of the state of hearing in the general population. Here, three facets of the subjective aspects of hearing loss are examined: frequent and bothersome tinnitus, ratings of hearing, and general well-being. The period prevalence of frequent, bothersome tinnitus varied with race and gender (13 to 17%) with higher rates among blacks and females. The mean air-conduction thresholds (0.5 to 4 kHz) of those reporting frequent and bothersome tinnitus did not exceed 32 dB HL. Mean audiograms associated with those who rated both ears good, fair, poor, or deaf were significantly different from each other. Mean poorer ear audiograms for those rating one ear as good were significantly better than those for comparable symmetrical ratings. Last, there was no clear, consistent relationship between audiometric thresholds and measures of well-being.
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Affiliation(s)
- J C Cooper
- Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio 78284-7777
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Cooper JC. Health and Nutrition Examination Survey of 1971-75: Part I. Ear and race effects in hearing. J Am Acad Audiol 1994; 5:30-6. [PMID: 8155892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The Health and Nutrition Examination Survey of 1971-75 contains unique hearing data because its design permits generalization to noninstitutionalized civilians in the continental United States. Air-conduction thresholds and their relationships to age, ear, gender, frequency, and race were examined in unscreened 25- to 74-year-olds. Although the observed effects of age, gender, and frequency were expected, three aspects of the results were remarkable. First, there was support for previous observations that older females have poorer low-frequency hearing. Second, there was an ear effect among white males who had poorer 2 and 4 kHz mean thresholds on the left at all ages. Third, there was a pattern of poorer mean thresholds for blacks that was particularly evident in comparisons between black and white females.
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Affiliation(s)
- J C Cooper
- Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio 78284-7777
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