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He CC, Hamlow LA, Roy HA, Devereaux ZJ, Hasan MA, Israel E, Cunningham NA, Martens J, Berden G, Oomens J, Rodgers MT. Structural Determination of Lysine-Linked Cisplatin Complexes via IRMPD Action Spectroscopy: NN s and NO - Binding Modes of Lysine to Platinum Coexist. J Phys Chem B 2022; 126:9246-9260. [PMID: 36326184 DOI: 10.1021/acs.jpcb.2c06234] [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: 11/06/2022]
Abstract
Despite its success as an anticancer drug, cisplatin suffers from resistance and produces side effects. To overcome these limitations, amino-acid-linked cisplatin analogues have been investigated. Lysine-linked cisplatin, Lysplatin, (Lys)PtCl2, exhibited outstanding reactivity toward DNA and RNA that differs from that of cisplatin. To gain insight into its differing reactivity, the structure of Lysplatin is examined here using infrared multiple photon dissociation (IRMPD) action spectroscopy. To probe the influence of the local chemical environment on structure, the deprotonated and sodium-cationized Lysplatin complexes are examined. Electronic structure calculations are performed to explore possible modes of binding of Lys to Pt, their relative stabilities, and to predict their infrared spectra. Comparisons of the measured IRMPD and predicted IR spectra elucidate the structures contributing to the experimental spectra. Coexistence of two modes of binding of Lys to Pt is found where Lys binds via the backbone and side-chain amino nitrogen atoms, NNs, or to the backbone amino and carboxylate oxygen atoms, NO-. Glycine-linked cisplatin and arginine-linked cisplatin complexes have previously been found to bind only via the NO- binding mode. Present results suggest that the NNs binding conformers may be key to the outstanding reactivity of Lysplatin toward DNA and RNA.
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Affiliation(s)
- C C He
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - L A Hamlow
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Zachary J Devereaux
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - M A Hasan
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - E Israel
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - J Martens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - G Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands.,Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Mikawy NN, Roy HA, Israel E, Hamlow LA, Zhu Y, Berden G, Oomens J, Frieler CE, Rodgers MT. 5-Halogenation of Uridine Suppresses Protonation-Induced Tautomerization and Enhances Glycosidic Bond Stability of Protonated Uridine: Investigations via IRMPD Action Spectroscopy, ER-CID Experiments, and Theoretical Calculations. J Am Soc Mass Spectrom 2022; 33:2165-2180. [PMID: 36279168 DOI: 10.1021/jasms.2c00231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Uridine (Urd), a canonical nucleoside of RNA, is the most commonly modified nucleoside among those that occur naturally. Uridine has also been an important target for the development of modified nucleoside analogues for pharmaceutical applications. In this work, the effects of 5-halogenation of uracil on the structures and glycosidic bond stabilities of protonated uridine nucleoside analogues are examined using tandem mass spectrometry and computational methods. Infrared multiple photon dissociation (IRMPD) action spectroscopy experiments and theoretical calculations are performed to probe the structural influences of these modifications. Energy-resolved collision-induced dissociation experiments along with survival yield analyses are performed to probe glycosidic bond stability. The measured IRMPD spectra are compared to linear IR spectra predicted for the stable low-energy conformations of these species computed at the B3LYP/6-311+G(d,p) level of theory to determine the conformations experimentally populated. Spectral signatures in the IR fingerprint and hydrogen-stretching regions allow the 2,4-dihydroxy protonated tautomers (T) and O4- and O2-protonated conformers to be readily differentiated. Comparisons between the measured and predicted spectra indicate that parallel to findings for uridine, both T and O4-protonated conformers of the 5-halouridine nucleoside analogues are populated, whereas O2-protonated conformers are not. Variations in yields of the spectral signatures characteristic of the T and O4-protonated conformers indicate that the extent of protonation-induced tautomerization is suppressed as the size of the halogen substituent increases. Trends in the energy-dependence of the survival yield curves find that 5-halogenation strengthens the glycosidic bond and that the enhancement in stability increases with the size of the halogen substituent.
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Affiliation(s)
- Neven N Mikawy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - E Israel
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - L A Hamlow
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Y Zhu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - G Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - J Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - C E Frieler
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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He CC, Hamlow LA, Kimutai B, Roy HA, Devereaux ZJ, Cunningham NA, Martens J, Berden G, Oomens J, Chow CS, Rodgers MT. Structural determination of arginine-linked cisplatin complexes via IRMPD action spectroscopy: arginine binds to platinum via NO - binding mode. Phys Chem Chem Phys 2021; 23:21959-21971. [PMID: 34569570 DOI: 10.1039/d1cp03407c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cisplatin, (NH3)2PtCl2, has been known as a successful metal-based anticancer drug for more than half a century. Its analogue, Argplatin, arginine-linked cisplatin, (Arg)PtCl2, is being investigated because it exhibits reactivity towards DNA and RNA that differs from that of cisplatin. In order to understand the basis for its altered reactivity, the deprotonated and sodium cationized forms of Argplatin, [(Arg-H)PtCl2]- and [(Arg)PtCl2 + Na]+, are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy in the IR fingerprint and hydrogen-stretching regions. Complementary electronic structure calculations are performed using density functional theory approaches to characterize the stable structures of these complexes and to predict their infrared spectra. Comparison of the theoretical IR spectra predicted for various stable conformations of these Argplatin complexes to their measured IRMPD spectra enables determination of the binding mode(s) of Arg to the Pt metal center to be identified. Arginine is found to bind to Pt in a bidentate fashion to the backbone amino nitrogen and carboxylate oxygen atoms in both the [(Arg-H)PtCl2]- and [(Arg)PtCl2 + Na]+ complexes, the NO- binding mode. The neutral side chain of Arg also interacts with the Pt center to achieve additional stabilization in the [(Arg-H)PtCl2]- complex. In contrast, Na+ binds to both chlorido ligands in the [(Arg)PtCl2 + Na]+ complex and the protonated side chain of Arg is stabilized via hydrogen-bonding interactions with the carboxylate moiety. These findings are consistent with condensed-phase results, indicating that the NO- binding mode of arginine to Pt is preserved in the electrospray ionization process even under variable pH and ionic strength.
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Affiliation(s)
- C C He
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - L A Hamlow
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - B Kimutai
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - Zachary J Devereaux
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - J Martens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - G Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED Nijmegen, The Netherlands
| | - J Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, 6525ED Nijmegen, The Netherlands.,van't Hoff Institute for Molecular Sciences, University of Amsterdam, The Netherlands
| | - C S Chow
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
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Roy HA, Rodgers MT. 1-Alkyl-3-methylimidazolium cation binding preferences in hexafluorophosphate ionic liquid clusters determined using competitive TCID measurements and theoretical calculations. Phys Chem Chem Phys 2021; 23:18145-18162. [PMID: 34612278 DOI: 10.1039/d1cp02928b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionic liquids (ILs) exhibit unique properties that have led to their development and widespread use for a variety of applications. Development efforts have generally focused on achieving desired macroscopic properties via tuning of the IL through variation of the cations and anions. Both the macroscopic and microscopic properties of an IL influence its tunability and thus feasibility of use for selected applications. Works geared toward a microscopic understanding of the nature and strength of the intrinsic cation-anion interactions of ILs have been limited to date. Specifically, the intrinsic strength of the cation-anion interactions in ILs is largely unknown. In previous work, we employed threshold collision-induced dissociation (TCID) approaches supported and enhanced by electronic structure calculations to determine the bond dissociation energies (BDEs) and characterize the nature of the cation-anion interactions in a series of four 2 : 1 clusters of 1-alkyl-3-methylimidazolium cations with the hexafluorophosphate anion, [2Cnmim:PF6]+. To examine the effects of the 1-alkyl chain on the structure and energetics of binding, the cation was varied over the series: 1-ethyl-3-methylimidazolium, [C2mim]+, 1-butyl-3-methylimidazolium, [C4mim]+, 1-hexyl-3-methylimidazolium, [C6mim]+, and 1-octyl-3-methylimidazolium, [C8mim]+. The variation in the strength of binding among these [2Cnmim:PF6]+ clusters was found to be similar in magnitude to the average experimental uncertainty in the measurements. To definitively establish an absolute order of binding among these [2Cnmim:PF6]+ clusters, we extend this work again using TCID and electronic structure theory approaches to include competitive binding studies of three mixed 2 : 1 clusters of 1-alkyl-3-methylimidazolium cations and the hexafluorophosphate anion, [Cn-2mim:PF6:Cnmim]+ for n = 4, 6, and 8. The absolute BDEs of these mixed [Cn-2mim:PF6:Cnmim]+ clusters as well as the absolute difference in the strength of the intrinsic binding interactions as a function of the cation are determined with significantly improved precision. By combining the thermochemical results of the previous independent and present competitive measurements, the BDEs of the [2Cnmim:PF6]+ clusters are both more accurately and more precisely determined. Comparisons are made to results for the analogous [2Cnmim:BF4]+ and [Cn-2mim:BF4:Cnmim]+ clusters previously examined to elucidate the effects of the [PF6]- and [BF4]- anions on the binding.
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Affiliation(s)
- H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
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Seidu YS, Roy HA, Rodgers MT. Influence of 5-Methylation and the 2'- and 3'-Hydroxy Substituents on the Base Pairing Energies of Protonated Cytidine Nucleoside Analogue Base Pairs: Implications for the Stabilities of i-Motif Structures. J Phys Chem A 2021; 125:5939-5955. [PMID: 34228469 DOI: 10.1021/acs.jpca.1c04303] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Repetitive nucleic acid sequences, which occur in abundance throughout the mammalian genome, are of enormous research interest due to their potential to adopt fascinating and unusual molecular structures such as the i-motif. In remarkable contrast to the DNA double helix, i-motif conformations are stabilized by protonated cytosine base pairs, (Cyt)H+(Cyt), that are centrally located in the core of the i-motif and intercalated vertically in an antiparallel fashion. An in-depth understanding of how modifications influence the stability of i-motif conformations is a prerequisite to understanding their biological functions and the development of effective means of tuning their stability for specific medical and technological applications. Here, the influence of the 2'- and 3'-hydroxy substituents of the sugar moieties and 5-methylation of the cytosine nucleobases on the base-pairing interactions of protonated cytidine nucleoside analogue base pairs, (xCyd)H+(xCyd), are examined by complementary threshold collision-induced dissociation techniques and computational methods. The xCyd nucleosides examined include the canonical DNA and RNA cytidine nucleosides, 2'-deoxycytidine (dCyd) and cytidine (Cyd), as well as several modified cytidine nucleoside analogues, 2',3'-dideoxycytidine (ddCyd), 5-methyl-2'-deoxycytidine (m5dCyd), and 5-methylcytidine (m5Cyd). Comparisons among these model base pairs indicate that the 2'- and 3'-hydroxy substituents of the sugar moieties have very little influence on the strength of the base-pairing interactions, whereas 5-methylation of the cytosine nucleobases is found to enhance the strength of the base-pairing interactions. The increase in stability resulting from 5-methylation is only modest but is more than twice as large for the DNA than RNA protonated cytidine base pair. Overall, present results suggest that canonical DNA i-motif conformations should be more stable than analogous RNA i-motif conformations and that 5-methylation of cytosine residues, a significant epigenetic marker, provides greater stabilization to DNA than RNA i-motif conformations.
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Affiliation(s)
- Yakubu S Seidu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Roy HA, Rodgers MT. Nature and strength of intrinsic cation-anion interactions of 1-alkyl-3-methylimidazolium hexafluorophosphate clusters. Phys Chem Chem Phys 2021; 23:13405-13418. [PMID: 34105537 DOI: 10.1039/d1cp01130h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Imidazolium-based cations and the hexafluorophosphate anion are among the most commonly used ionic liquids (ILs). Yet, the nature and strength of the intrinsic cation-anion interactions, and how they influence the macroscopic properties of these ILs are still not well understood. Threshold collision-induced dissociation is utilized to determine the bond dissociation energies (BDEs) of the 2 : 1 clusters of 1-alkyl-3-methylimidazolium cations and the hexafluorophosphate anion, [2Cnmim:PF6]+. The cation, [Cnmim]+, is varied across the series, 1-ethyl-3-methylimidazolium [C2mim]+, 1-butyl-3-methylimidazolium [C4mim]+, 1-hexyl-3-methylimidazolium [C6mim]+, 1-octyl-3-methylimidazolium [C8mim]+, to examine the structural and energetic effects of the size of the 1-alkyl substituent of the cation on the binding to [PF6]-. Complementary electronic structure methods are employed for the [Cnmim]+ cations, (Cnmim:PF6) ion pairs, and [2Cnmim:PF6]+ clusters to elucidate details of the cation-anion interactions and their impact on structure and energetics. Multiple levels of theory are benchmarked with the measured BDEs including B3LYP, B3LYP-GD3BJ, and M06-2X each with the 6-311+G(d,p) basis set for geometry optimizations and frequency analyses and the 6-311+G(2d,2p) basis set for energetic determinations. The modest structural variation among the [Cnmim]+ cations produces only minor structural changes and variation in the measured BDEs of the [2Cnmim:PF6]+ clusters. Present results are compared to those previously reported for the analogous 1-alkyl-3-methylimidazolium tetrafluoroborate IL clusters to compare the effects of these anions on the nature and strength of the intrinsic binding interactions.
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Affiliation(s)
- H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
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Roy HA, Cascini N, Ajay B, Mukherjee S, McGavin L, Inman A, Wilkinson R, Whitfield PC. Intracranial tuberculoma and the challenges of global neurosurgery. ACNR 2021. [DOI: 10.47795/wbyy8184] [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: 11/18/2022] Open
Abstract
In a world of increasing globalisation, Neurosurgeons need to be able to diagnose and treat neurosurgical conditions which may not be common to the local population. To illustrate this, we describe the case of an intracranial tuberculoma presenting in the post-partum period. Tuberculosis (TB) is a widely recognised mimic of other conditions, including high grade gliomas, which can result in diagnostic delays. We highlight clinical features that should increase the index of suspicion for TB and create a low threshold for trial of empirical treatment. We also discuss educational partnership strategies that may help facilitate global perspectives in neurosurgical training.
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Roy HA, Rodgers MT. Absolute Trends and Accurate and Precise Gas-Phase Binding Energies of 1-Alkyl-3-Methylimidazolium Tetrafluoroborate Ionic Liquid Clusters from Combined Independent and Competitive TCID Measurements. J Phys Chem A 2020; 124:10199-10215. [PMID: 33231458 DOI: 10.1021/acs.jpca.0c07246] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ionic liquid (IL) development efforts have focused on achieving desired properties via tuning of the IL through variation of the cations and anions. However, works geared toward a microscopic understanding of the nature and strength of the intrinsic cation-anion interactions of ILs have been rather limited such that the intrinsic strength of the cation-anion interactions in ILs is largely unknown. In previous work, we employed threshold collision-induced dissociation approaches supported and enhanced by electronic structure calculations to characterize the nature of the cation-anion interactions in and determine the bond dissociation energies (BDEs) of a series of four 2:1 clusters of 1-alkyl-3-methylimidazolium cations and tetrafluoroborate anions, [2Cnmim:BF4]+. The cation was varied over the series: 1-ethyl-3-methylimidazolium, [C2mim]+, 1-butyl-3-methylimidazolium, [C4mim]+, 1-hexyl-3-methylimidazolium, [C6mim]+, and 1-octyl-3-methylimidazolium, [C8mim]+, to determine the structural and energetic effects of the size of the 1-alkyl substituent on the binding. The variation in the strength of binding determined for these [2Cnmim:BF4]+ clusters was found to be similar in magnitude to the average experimental uncertainty in these determinations. To definitively establish an absolute order of binding among these [2Cnmim:BF4]+ clusters, we extend this work here to include competitive binding studies of three mixed 2:1 clusters of 1-alkyl-3-methylimidazolium cations and tetrafluoroborate anions, [Cn-2mim:BF4:Cnmim]+ for n = 4, 6, and 8. Importantly, the results of the present work simultaneously provide the absolute BDEs of these mixed [Cn-2mim:BF4:Cnmim]+ clusters and the absolute relative order of the intrinsic binding interactions as a function of the cation with significantly improved precision. Further, by combining the thermochemical results of the previous and present studies, the BDEs of the [2Cnmim:BF4]+ clusters are more accurately and precisely determined.
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Affiliation(s)
- H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Roy HA, Hamlow LA, Rodgers MT. Gas-Phase Binding Energies and Dissociation Dynamics of 1-Alkyl-3-Methylimidazolium Tetrafluoroborate Ionic Liquid Clusters. J Phys Chem A 2020; 124:10181-10198. [PMID: 33231466 DOI: 10.1021/acs.jpca.0c06297] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ionic liquids (ILs) have become increasingly popular due to their useful and unique properties, yet there are still many unanswered questions regarding their fundamental interactions. In particular, details regarding the nature and strength of the intrinsic cation-anion interactions and how they influence the macroscopic properties of ILs are still largely unknown. Elucidating the molecular-level details of these interactions is essential to the development of better models for describing ILs and enabling the purposeful design of ILs with properties tailored for specific applications. Current uses of ILs are widespread and diverse and include applications for energy storage, electrochemistry, designer/green solvents, separations, and space propulsion. To advance the understanding of the energetics, conformations, and dynamics of gas-phase IL clustering relevant to space propulsion, threshold collision-induced dissociation approaches are used to measure the bond dissociation energies (BDEs) of the 2:1 clusters of 1-alkyl-3-methylimidazolium cations and tetrafluoroborate, [2Cnmim:BF4]+. The cation, [Cnmim]+, is varied across the series, 1-ethyl-3-methylimidazolium [C2mim]+, 1-butyl-3-methylimidazolium [C4mim]+, 1-hexyl-3-methylimidazolium [C6mim]+, and 1-octyl-3-methylimidazolium [C8mim]+, to examine the structural and energetic effects of the size of the 1-alkyl substituent on binding. Complementary electronic structure calculations are performed to determine the structures and energetics of the [Cnmim]+ and [BF4]- ions and their binding preferences in the (Cnmim:BF4) ion pairs and [2Cnmim:BF4]+ clusters. Several levels of theory, B3LYP, B3LYP-GD3BJ, and M06-2X, using the 6-311+G(d,p) basis set for geometry optimizations and frequency analyses and the 6-311+G(2d,2p) basis set for energetics, are benchmarked to examine their abilities to properly describe the nature of the binding interactions and to reproduce the measured BDEs. The modest structural variation among these [Cnmim]+ cations produces only minor structural changes and variation in the measured BDEs of the [2Cnmim:BF4]+ clusters. Present findings indicate that the dominant cation-anion interactions involve the 3-methylimidazolium moieties and that these clusters are sufficiently small that differences in packing effects associated with the variable length of the 1-alkyl substituents are not yet significant.
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Affiliation(s)
- H A Roy
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - L A Hamlow
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Roy HA, Nettleton J, Blain C, Dalton C, Farhan B, Fernandes A, Georgopoulos P, Klepsch S, Lavelle J, Martinelli E, Panicker JN, Radoja I, Rapidi CA, Pereira E Silva R, Tudor K, Wagg AS, Drake MJ. Assessment of patients with lower urinary tract symptoms where an undiagnosed neurological disease is suspected: A report from an International Continence Society consensus working group. Neurourol Urodyn 2020; 39:2535-2543. [PMID: 32754994 DOI: 10.1002/nau.24469] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/10/2022]
Abstract
AIM Lower urinary tract symptoms (LUTS) are a common urological referral, which sometimes can have a neurological basis in a patient with no formally diagnosed neurological disease ("occult neurology"). Early identification and specialist input is needed to avoid bad LUTS outcomes, and to initiate suitable neurological management. METHODS The International Continence Society established a neurological working group to consider: Which neurological conditions may include LUTS as an early feature? What diagnostic evaluations should be undertaken in the LUTS clinic? A shortlist of conditions was drawn up by expert consensus and discussed at the annual congress of the International Neurourology Society. A multidisciplinary working group then generated recommendations for identifying clinical features and management. RESULTS The relevant conditions are multiple sclerosis, multiple system atrophy, normal pressure hydrocephalus, early dementia, Parkinsonian syndromes (including early Parkinson's Disease and Multiple System Atrophy) and spinal cord disorders (including spina bifida occulta with tethered cord, and spinal stenosis). In LUTS clinics, the need is to identify additional atypical features; new onset severe LUTS (excluding infection), unusual aspects (eg, enuresis without chronic retention) or "suspicious" symptoms (eg, numbness, weakness, speech disturbance, gait disturbance, memory loss/cognitive impairment, and autonomic symptoms). Where occult neurology is suspected, healthcare professionals need to undertake early appropriate referral; central nervous system imaging booked from LUTS clinic is not recommended. CONCLUSIONS Occult neurology is an uncommon underlying cause of LUTS, but it is essential to intervene promptly if suspected, and to establish suitable management pathways.
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Affiliation(s)
- Holly A Roy
- Neurosurgery Department, Derriford Hospital, University Hospitals Plymouth NHS Trust, Plymouth, UK
| | - Jeremy Nettleton
- Department of Urology, Cheltenham General Hospital, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, UK
| | - Camilla Blain
- Atkinson Morley Regional Neurosciences Centre, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Catherine Dalton
- Atkinson Morley Regional Neurosciences Centre, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Bilal Farhan
- UTMB Health Division of Urology, Galveston, Texas
| | - Ailton Fernandes
- Department of Urology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Petros Georgopoulos
- Department of Urology and Pelvic Floor Unit, Aarhus University Hospital, Aarhus, Denmark
| | - Sabine Klepsch
- Neurology Department, Southmead Hospital, North Bristol NHS Trust, Bristol, UK
| | - John Lavelle
- Veteran Affairs Palo Alto Health Care System, Palo Alto, California
| | | | - Jalesh N Panicker
- Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
| | - Ivan Radoja
- Department of Urology, University Hospital Centre Osijek, Faculty of Medicine, The J. J. Strossmayer University of Osijek, Osijek, Croatia
| | | | - Ricardo Pereira E Silva
- Department of Urology, Centro Hospitalar Universitário Lisboa Norte, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Katarina Tudor
- Department of Neurology, Unit for Headaches, Neurogenic Pain and Spinal Disorders, School of Medicine, University Hospital Centre Zagreb, University of Zagreb, Zagreb, Croatia
| | - Adrian S Wagg
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Marcus J Drake
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol Urological Institute, Bristol, UK
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Devereaux ZJ, He CC, Zhu Y, Roy HA, Cunningham NA, Hamlow LA, Berden G, Oomens J, Rodgers MT. Structures and Relative Glycosidic Bond Stabilities of Protonated 2'-Fluoro-Substituted Purine Nucleosides. J Am Soc Mass Spectrom 2019; 30:1521-1536. [PMID: 31111413 DOI: 10.1007/s13361-019-02222-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 04/10/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
The 2'-substituent is the primary distinguishing feature between DNA and RNA nucleosides. Modifications to this critical position, both naturally occurring and synthetic, can produce biologically valuable nucleoside analogues. The unique properties of fluorine make it particularly interesting and medically useful as a synthetic nucleoside modification. In this work, the effects of 2'-fluoro modification on the protonated gas-phase purine nucleosides are examined using complementary tandem mass spectrometry and computational methods. Direct comparisons are made with previous studies on related nucleosides. Infrared multiple photon dissociation action spectroscopy performed in both the fingerprint and hydrogen-stretching regions allows for the determination of the experimentally populated conformations. The populated conformers of protonated 2'-fluoro-2'-deoxyadenosine, [Adofl+H]+, and 2'-fluoro-2'-deoxyguanosine, [Guofl+H]+, are highly parallel to their respective canonical DNA and RNA counterparts. Both N3 and N1 protonation sites are accessed by [Adofl+H]+, stabilizing syn and anti nucleobase orientations, respectively. N7 protonation and anti nucleobase orientation dominates in [Guofl+H]+. Spectroscopically observable intramolecular hydrogen-bonding interactions with fluorine allow more definitive sugar puckering determinations than possible for the canonical systems. [Adofl+H]+ adopts C2'-endo sugar puckering, whereas [Guofl+H]+ adopts both C2'-endo and C3'-endo sugar puckering. Energy-resolved collision-induced dissociation experiments with survival yield analyses provide relative glycosidic bond stabilities. The N-glycosidic bond stabilities of the protonated 2'-fluoro-substituted purine nucleosides are found to exceed those of their canonical analogues. Further, the N-glycosidic bond stability is found to increase with increasing electronegativity of the 2'-substituent, i.e., H < OH < F. The N-glycosidic bond stability is also greater for the adenine nucleoside analogues than the guanine nucleoside analogues.
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Affiliation(s)
- Zachary J Devereaux
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - C C He
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - Y Zhu
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - H A Roy
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - N A Cunningham
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - L A Hamlow
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - G Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525 ED, Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525 ED, Nijmegen, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA.
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Roy HA, Aziz TZ, Green AL. Sensory thalamus and periaqueductal grey area local field potential signals during bladder filling. J Clin Neurosci 2019; 68:342-343. [PMID: 31331745 DOI: 10.1016/j.jocn.2019.07.037] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/08/2019] [Indexed: 10/26/2022]
Abstract
The periaqueductal grey area and sensory thalamus are thought to be important nuclei involved in the supraspinal bladder control network. Deep brain stimulation of the periqueductal grey area has been shown to increase bladder capacity in the human. In a single patient, we have recorded local field potential signals from implanted deep brain stimulation electrodes within the sensory thalamus during filling cystometry with periaqueductal grey area deep brain stimulation in the ON and OFF states. In the OFF stimulation state, we demonstrate correlations between bladder volume and oscillations in the high gamma frequency band in the sensory thalamus. Stimulation of the periaqueductal grey area abolishes this correlated activity in the gamma frequency band and also suppresses oscillations within the sensory thalamus in the alpha frequency band. These findings support the involvement of the sensory thalamus in the afferent limb of bladder-related brain networks. They also suggest that periaqueductal grey area deep brain stimulation may disrupt the normal processing of afferent signals within the sensory thalamus which may be related to the effect of stimulation on bladder capacity.
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Affiliation(s)
- Holly A Roy
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, Oxford, UK.
| | - Tipu Z Aziz
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, Oxford, UK; Department of Neurosurgery, Level 3, The West Wing, John Radcliffe Hospital, Oxford, UK
| | - Alexander L Green
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, Oxford, UK; Department of Neurosurgery, Level 3, The West Wing, John Radcliffe Hospital, Oxford, UK
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13
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Green AL, Debrah E, Roy HA, Rebelo P, Moosavi SH. Letter to the editor: Thalamic deep brain stimulation may relieve breathlessness in COPD. Brain Stimul 2019; 12:827-828. [PMID: 30867117 DOI: 10.1016/j.brs.2019.02.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/20/2019] [Accepted: 02/22/2019] [Indexed: 11/17/2022] Open
Affiliation(s)
- A L Green
- Nuffield Department of Surgical Sciences, University of Oxford, UK.
| | - E Debrah
- Nuffield Department of Surgical Sciences, University of Oxford, UK; Cardiorespiratory Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
| | - H A Roy
- Nuffield Department of Surgical Sciences, University of Oxford, UK.
| | - P Rebelo
- Nuffield Department of Surgical Sciences, University of Oxford, UK.
| | - S H Moosavi
- Cardiorespiratory Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
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Hamlow LA, Devereaux ZJ, Roy HA, Cunningham NA, Berden G, Oomens J, Rodgers MT. Impact of the 2'- and 3'-Sugar Hydroxyl Moieties on Gas-Phase Nucleoside Structure. J Am Soc Mass Spectrom 2019; 30:832-845. [PMID: 30850972 DOI: 10.1007/s13361-019-02155-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 02/12/2019] [Accepted: 02/12/2019] [Indexed: 06/09/2023]
Abstract
Modified nucleosides have been an important target for pharmaceutical development for the treatment of cancer, herpes simplex virus, and the human immunodeficiency virus (HIV). Amongst these nucleoside analogues, those based on 2',3'-dideoxyribose sugars are quite common, particularly in anti-HIV applications. The gas-phase structures of several protonated 2',3'-dideoxyribose nucleosides are examined in this work and compared with those of the analogous protonated DNA, RNA, and arabinose nucleosides to elucidate the influence of the 2'- and combined 2',3'-hydroxyl groups on intrinsic structure. Infrared multiple photon dissociation (IRMPD) action spectra are collected for the protonated 2',3'-dideoxy forms of adenosine, guanosine, cytidine, thymidine and uridine, [ddAdo+H]+, [ddGuo+H]+, [ddCyd+H]+, [ddThd+H]+, and [ddUrd+H]+, in the IR fingerprint and hydrogen-stretching regions. Molecular mechanics conformational searching followed by electronic structure calculations generates low-energy conformers of the protonated 2',3'-dideoxynucleosides and corresponding predicted linear IR spectra to facilitate interpretation of the measured IRMPD action spectra. These experimental IRMPD spectra and theoretical calculations indicate that the absence of the 2'- and 3'-hydroxyls largely preserves the protonation preferences of the canonical forms. The spectra and calculated structures indicate a slight preference for C3'-endo sugar puckering. The presence of the 3'- and further 2'-hydroxyl increases the available intramolecular hydrogen-bonding opportunities and shifts the sugar puckering modes for all nucleosides but the guanosine analogues to a slight preference for C2'-endo over C3'-endo. Graphical Abstract.
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Affiliation(s)
- L A Hamlow
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, MI, 48202, USA
| | - Zachary J Devereaux
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, MI, 48202, USA
| | - H A Roy
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, MI, 48202, USA
| | - N A Cunningham
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, MI, 48202, USA
| | - G Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, MI, 48202, USA.
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Roy HA, Griffiths DJ, Aziz TZ, Green AL, Menke RAL. Investigation of urinary storage symptoms in Parkinson's disease utilizing structural MRI techniques. Neurourol Urodyn 2019; 38:1168-1175. [PMID: 30869824 DOI: 10.1002/nau.23976] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 11/09/2018] [Revised: 02/17/2019] [Accepted: 02/26/2019] [Indexed: 01/26/2023]
Abstract
BACKGROUND Lower urinary tract symptoms occur in 27% to 86% of patients with Parkinson's disease (PD), however, the mechanisms responsible for bladder dysfunction are not fully understood. This study utilized magnetic resonance imaging (MRI) to test the hypothesis that key brainstem bladder control areas (including the pontine micturition center and the pontine continence center (PCC) and their links with the basal ganglia are important in the development of urinary storage symptoms in PD. METHODS Seventeen patients with PD completed a "bladder symptom questionnaire" and underwent diffusion-weighted MRI (1.5 T). Storage symptom severity and MRI measures of white matter microstructural integrity were correlated using tract-based spatial statistics. RESULTS Mean diffusivity in the ventral brainstem correlated significantly with the bladder symptom severity in areas close to the predicted anatomical co-ordinates of the PCC. Tracts seeded from these regions passed via areas involved in pelvic floor musculature control and urinary voiding including the cerebellum, pallidum, and precentral gyrus. CONCLUSION We used diffusion-weighted MRI to investigate the role of the brainstem and its structural connections in the development of urinary storage symptoms in PD. Our data suggest that the brainstem degenerative change in the vicinity of the PCC may be implicated in the pathogenesis of storage symptoms in these patients.
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Affiliation(s)
- Holly A Roy
- Department of Functional Neurosurgery, John Radcliffe Hospital, Oxford, United Kingdom.,Nuffield Department of Surgical Sciences, University of Oxford, Oxford, United Kingdom
| | - Derek J Griffiths
- Division of Geriatric Medicine and Institute on Ageing (retired), University of Pittsburgh
| | - Tipu Z Aziz
- Department of Functional Neurosurgery, John Radcliffe Hospital, Oxford, United Kingdom.,Nuffield Department of Surgical Sciences, University of Oxford, Oxford, United Kingdom
| | - Alexander L Green
- Department of Functional Neurosurgery, John Radcliffe Hospital, Oxford, United Kingdom.,Nuffield Department of Surgical Sciences, University of Oxford, Oxford, United Kingdom
| | - Ricarda A L Menke
- Oxford Centre for Functional Magnetic Resonance of the Brain, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom.,Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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Roy HA, Aziz TZ, Fitzgerald JJ, Green AL. Beta oscillations and urinary voiding in Parkinson disease. Neurology 2018; 90:e1530-e1534. [PMID: 29572280 DOI: 10.1212/wnl.0000000000005355] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 01/18/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES To investigate the role of beta oscillations in urinary voiding and their association with lower urinary tract symptoms in Parkinson disease (PD). METHODS We used surgically implanted deep brain stimulation electrodes to record local field potential signals from the subthalamic nucleus (STN) and globus pallidus interna (GPi) of patients with PD during urinary voiding. Five patients with STN electrodes and 5 patients with GPi electrodes were tested. We also explored correlations between beta oscillatory power and urinary symptoms assessed by the International Consultation on Incontinence Lower Urinary Tract Symptoms questionnaire. RESULTS Beta suppression occurred during urinary voiding in the GPi (p < 0.05) but not the STN. Furthermore, the beta signal in the GPi during voiding correlated significantly with severity of incontinence and urinary frequency (p < 0.05). CONCLUSIONS In this study, we have demonstrated that local field potentials can provide information about the neural control of the bladder. Our findings suggest that the GPi is implicated in the process of urinary voiding and that its mechanism of action is linked to signals in the beta frequency band. Moreover, our correlational analyses show that beta oscillations may be implicated more generally in the pathophysiology of lower urinary tract symptoms in PD.
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Affiliation(s)
- Holly A Roy
- From the Department of Functional Neurosurgery (H.A.R., T.Z.A., J.J.F., A.L.G.) and Nuffield Department of Surgical Sciences (H.A.R., T.Z.A., J.J.F., A.L.G.), John Radcliffe Hospital, Oxford; and Department of Neurosurgery (H.A.R.), Derriford Hospital, Plymouth, UK.
| | - Tipu Z Aziz
- From the Department of Functional Neurosurgery (H.A.R., T.Z.A., J.J.F., A.L.G.) and Nuffield Department of Surgical Sciences (H.A.R., T.Z.A., J.J.F., A.L.G.), John Radcliffe Hospital, Oxford; and Department of Neurosurgery (H.A.R.), Derriford Hospital, Plymouth, UK
| | - James J Fitzgerald
- From the Department of Functional Neurosurgery (H.A.R., T.Z.A., J.J.F., A.L.G.) and Nuffield Department of Surgical Sciences (H.A.R., T.Z.A., J.J.F., A.L.G.), John Radcliffe Hospital, Oxford; and Department of Neurosurgery (H.A.R.), Derriford Hospital, Plymouth, UK
| | - Alexander L Green
- From the Department of Functional Neurosurgery (H.A.R., T.Z.A., J.J.F., A.L.G.) and Nuffield Department of Surgical Sciences (H.A.R., T.Z.A., J.J.F., A.L.G.), John Radcliffe Hospital, Oxford; and Department of Neurosurgery (H.A.R.), Derriford Hospital, Plymouth, UK
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17
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Akinyemi TE, Wu RR, Nei YW, Cunningham NA, Roy HA, Steill JD, Berden G, Oomens J, Rodgers MT. Influence of Transition Metal Cationization versus Sodium Cationization and Protonation on the Gas-Phase Tautomeric Conformations and Stability of Uracil: Application to [Ura+Cu] + and [Ura+Ag]<sup/>. J Am Soc Mass Spectrom 2017; 28:2438-2453. [PMID: 28895083 DOI: 10.1007/s13361-017-1771-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 07/22/2017] [Accepted: 07/22/2017] [Indexed: 05/17/2023]
Abstract
The gas-phase conformations of transition metal cation-uracil complexes, [Ura+Cu]+ and [Ura+Ag]+, were examined via infrared multiple photon dissociation (IRMPD) action spectroscopy and theoretical calculations. IRMPD action spectra were measured over the IR fingerprint and hydrogen-stretching regions. Structures and linear IR spectra of the stable tautomeric conformations of these complexes were initially determined at the B3LYP/6-31G(d) level. The four most stable structures computed were also examined at the B3LYP/def2-TZVPPD level to improve the accuracy of the predicted IR spectra. Two very favorable modes of binding are found for [Ura+Cu]+ and [Ura+Ag]+ that involve O2N3 bidentate binding to the 2-keto-4-hydroxy minor tautomer and O4 monodentate binding to the canonical 2,4-diketo tautomer of Ura. Comparisons between the measured IRMPD and calculated IR spectra enable elucidation of the conformers present in the experiments. These comparisons indicate that both favorable binding modes are represented in the experimental tautomeric conformations of [Ura+Cu]+ and [Ura+Ag]+. B3LYP suggests that Cu+ exhibits a slight preference for O4 binding, whereas Ag+ exhibits a slight preference for O2N3 binding. In contrast, MP2 suggests that both Cu+ and Ag+ exhibit a more significant preference for O2N3 binding. The relative band intensities suggest that O4 binding conformers comprise a larger portion of the population for [Ura+Ag]+ than [Ura+Cu]+. The dissociation behavior and relative stabilities of the [Ura+M]+ complexes, M+ = Cu+, Ag+, H+, and Na+) are examined via energy-resolved collision-induced dissociation experiments. The IRMPD spectra, dissociation behaviors, and binding preferences of Cu+ and Ag+ are compared with previous and present results for those of H+ and Na+. Graphical Abstract ᅟ.
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Affiliation(s)
- T E Akinyemi
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - R R Wu
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - Y-W Nei
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - J D Steill
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
| | - G Berden
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
- van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
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Zhu Y, Roy HA, Cunningham NA, Strobehn SF, Gao J, Munshi MU, Berden G, Oomens J, Rodgers MT. IRMPD Action Spectroscopy, ER-CID Experiments, and Theoretical Studies of Sodium Cationized Thymidine and 5-Methyluridine: Kinetic Trapping During the ESI Desolvation Process Preserves the Solution Structure of [Thd+Na]<sup/>. J Am Soc Mass Spectrom 2017; 28:2423-2437. [PMID: 28836109 DOI: 10.1007/s13361-017-1753-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/01/2017] [Accepted: 07/02/2017] [Indexed: 05/25/2023]
Abstract
Thymidine (dThd) is a fundamental building block of DNA nucleic acids, whereas 5-methyluridine (Thd) is a common modified nucleoside found in tRNA. In order to determine the conformations of the sodium cationized thymine nucleosides [dThd+Na]+ and [Thd+Na]+ produced by electrospray ionization, their infrared multiple photon dissociation (IRMPD) action spectra are measured. Complementary electronic structure calculations are performed to determine the stable low-energy conformations of these complexes. Geometry optimizations and frequency analyses are performed at the B3LYP/6-311+G(d,p) level of theory, whereas energies are calculated at the B3LYP/6-311+G(2d,2p) level of theory. As protonation preferentially stabilizes minor tautomers of dThd and Thd, tautomerization facilitated by Na+ binding is also considered. Comparisons of the measured IRMPD and computed IR spectra find that [dThd+Na]+ prefers tridentate (O2,O4',O5') coordination to the canonical 2,4-diketo form of dThd with thymine in a syn orientation. In contrast, [Thd+Na]+ prefers bidentate (O2,O2') coordination to the canonical 2,4-diketo tautomer of Thd with thymine in an anti orientation. Although 2,4-dihydroxy tautomers and O2 protonated thymine nucleosides coexist in the gas phase, no evidence for minor tautomers is observed for the sodium cationized species. Consistent with experimental observations, the computational results confirm that the sodium cationized thymine nucleosides exhibit a strong preference for the canonical form of the thymine nucleobase. Survival yield analyses based on energy-resolved collision-induced dissociation (ER-CID) experiments suggest that the relative stabilities of protonated and sodium cationized dThd and Thd follow the order [dThd+H]+ < [Thd+H]+ < [dThd+Na]+ < [Thd+Na]+. Graphical Abstract ᅟ.
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Affiliation(s)
- Y Zhu
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - S F Strobehn
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - J Gao
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - M U Munshi
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - G Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525ED, Nijmegen, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
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Zhu Y, Roy HA, Cunningham NA, Strobehn SF, Gao J, Munshi MU, Berden G, Oomens J, Rodgers MT. Effects of sodium cationization versus protonation on the conformations and N-glycosidic bond stabilities of sodium cationized Urd and dUrd: solution conformation of [Urd+Na] + is preserved upon ESI. Phys Chem Chem Phys 2017; 19:17637-17652. [PMID: 28665436 DOI: 10.1039/c7cp02377d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Uridine (Urd) is one of the naturally occurring pyrimidine nucleosides of RNA. 2'-Deoxyuridine (dUrd) is a naturally occurring modified form of Urd, but is not one of the canonical DNA nucleosides. In order to understand the effects of sodium cationization on the conformations and energetics of Urd and dUrd, infrared multiple photon dissociation (IRMPD) action spectroscopy experiments and density functional theory (DFT) calculations are performed. By comparing the calculated IR spectra of [Urd+Na]+ and [dUrd+Na]+ with the measured IRMPD spectra, the stable low-energy conformers populated in the experiments are determined. Anti oriented bidentate O2 and O2' binding conformers of [Urd+Na]+ are the dominant conformers populated in the experiments, whereas syn oriented tridentate O2, O4', and O5' binding conformers of [dUrd+Na]+ are dominantly populated in the experiments. The 2'-hydroxyl substituent of Urd stabilizes the anti oriented O2 binding conformers of [Urd+Na]+. Significant differences between the measured IRMPD and calculated IR spectra for complexes of [Urd+Na]+ and [dUrd+Na]+ involving minor tautomeric forms of the nucleobase make it obvious that none are populated in the experiments. Survival yield analyses based on energy-resolved collision-induced dissociation (ER-CID) experiments suggest that the relative stabilities of protonated and sodium cationized Urd and dUrd follow the order: [dUrd+H]+ < [Urd+H]+ < [dUrd+Na]+ < [Urd+Na]+. The 2'-deoxy modification is found to weaken the glycosidic bond of dUrd versus that of Urd for the sodium cationized uridine nucleosides.
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Affiliation(s)
- Y Zhu
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - S F Strobehn
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - J Gao
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - M U Munshi
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - G Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - J Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
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Roy HA, Pond D, Roy C, Forrow B, Foltynie T, Zrinzo L, Akram H, Aziz TZ, FitzGerald JJ, Green AL. Effects of pedunculopontine nucleus stimulation on human bladder function. Neurourol Urodyn 2017; 37:726-734. [DOI: 10.1002/nau.23321] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 04/11/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Holly A. Roy
- Department of Neurosurgery; Oxford University Hospitals Trust; Oxford UK
- Nuffield Department of Surgical Sciences; University of Oxford; Oxford UK
| | - Debbie Pond
- OUH Adult Continence Service, Infection Control Department; Oxford University Hospitals Trust; Oxford UK
| | | | - Beth Forrow
- Department of Neurosurgery; Oxford University Hospitals Trust; Oxford UK
| | - Thomas Foltynie
- Sobell Department of Motor Neuroscience and Movement Disorders; University College London, Institute of Neurology; London UK
| | - Ludvic Zrinzo
- Sobell Department of Motor Neuroscience and Movement Disorders; University College London, Institute of Neurology; London UK
| | - Harith Akram
- Sobell Department of Motor Neuroscience and Movement Disorders; University College London, Institute of Neurology; London UK
| | - Tipu Z. Aziz
- Department of Neurosurgery; Oxford University Hospitals Trust; Oxford UK
- Nuffield Department of Surgical Sciences; University of Oxford; Oxford UK
| | - James J. FitzGerald
- Department of Neurosurgery; Oxford University Hospitals Trust; Oxford UK
- Nuffield Department of Surgical Sciences; University of Oxford; Oxford UK
| | - Alexander L. Green
- Department of Neurosurgery; Oxford University Hospitals Trust; Oxford UK
- Nuffield Department of Surgical Sciences; University of Oxford; Oxford UK
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21
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Roy HA, Green AL, Aziz TZ. State of the Art: Novel Applications for Deep Brain Stimulation. Neuromodulation 2017; 21:126-134. [DOI: 10.1111/ner.12604] [Citation(s) in RCA: 12] [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] [Received: 12/05/2016] [Revised: 02/19/2017] [Accepted: 03/11/2017] [Indexed: 02/06/2023]
Affiliation(s)
- Holly A. Roy
- Nuffield Department of Surgical Sciences; Oxford University; Oxford UK
- Neurosurgery Department; Oxford University Hospitals; Oxford UK
| | - Alexander L. Green
- Nuffield Department of Surgical Sciences; Oxford University; Oxford UK
- Neurosurgery Department; Oxford University Hospitals; Oxford UK
| | - Tipu Z. Aziz
- Nuffield Department of Surgical Sciences; Oxford University; Oxford UK
- Neurosurgery Department; Oxford University Hospitals; Oxford UK
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Roy HA, Magdum S. Sub-aponeurotic fluid collection in a neonate associated with fetal scalp electrode monitoring: a brief communication. Eur J Obstet Gynecol Reprod Biol 2014; 181:343-4. [DOI: 10.1016/j.ejogrb.2014.07.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 06/19/2014] [Accepted: 07/20/2014] [Indexed: 11/28/2022]
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Abstract
Deep brain stimulation is a neurosurgical technique that can be used to alleviate symptoms in a growing number of neurological conditions through modulating activity within brain networks. Certain applications of deep brain stimulation are relevant for the management of symptoms in multiple sclerosis. In this paper we discuss existing treatment options for tremor, facial pain and urinary dysfunction in multiple sclerosis and discuss evidence to support the potential use of deep brain stimulation for these symptoms.
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Affiliation(s)
- Holly A Roy
- Nuffield Department of Surgical Science, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Tipu Z Aziz
- Nuffield Department of Surgical Science, John Radcliffe Hospital, Oxford OX3 9DU, UK.
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