1
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Humber DC, Bamford MJ, Bethell RC, Cammack N, Orr DC, Storer R, Weingarten GG, Wyatt PG. Synthesis and Structure Activity Relationships of a Series of Penicillin-Derived Pseudosymmetric Inhibitors of HIV-1 Proteinase. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/095632029400500311] [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: 11/15/2022]
Abstract
The synthesis from penicillin G of a series of potent pseudosymmetric inhibitors 11 a-k of HIV-1 proteinase is described. The 2-pyridyl substituted compounds 11a and 11j showed improved antiviral activity compared to their C2-symmetric counterparts 3 and 4.
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Affiliation(s)
- D. C. Humber
- Departments of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - M. J. Bamford
- Departments of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - R. C. Bethell
- Departments of Virology, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - N. Cammack
- Departments of Virology, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - D. C. Orr
- Departments of Virology, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - R. Storer
- Departments of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - G. G. Weingarten
- Departments of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
| | - P. G. Wyatt
- Departments of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, UB6 0HE, UK
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2
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Leroy F, Chaves D, Dukhan D, Storer R, Sommadossi JP, Loi AG, Cadeddu A, Fanti M, Boscu N, Bassetti F, Liuzzi M, Gosselin G. Synthesis and antiviral evaluation of 7-fluoro-7-deaza-2-aminopurine nucleoside derivatives. ACTA ACUST UNITED AC 2008:595-6. [DOI: 10.1093/nass/nrn301] [Citation(s) in RCA: 4] [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] [Indexed: 11/12/2022]
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3
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Sizun G, Griffon JF, Griffe L, Dukhan D, Storer R, Sommadossi JP, Loi AG, Musiu C, Poddesu B, Cadeddu A, Fanti M, Boscu N, Bassetti F, Liuzzi M, Gosselin G. Synthesis and antiviral evaluation of a seven-membered sugar ring nucleoside analog, 9-(5-deoxy- -D-allo-septanosyl)-adenine. ACTA ACUST UNITED AC 2008:611-2. [DOI: 10.1093/nass/nrn309] [Citation(s) in RCA: 4] [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] [Indexed: 11/13/2022]
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4
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Leroy F, Chaves D, Dukhan D, Storer R, Sommadossi JP, Loi AG, Cadeddu A, Fanti M, Boscu N, Bassetti F, Liuzzi M, Gosselin G. Synthesis and antiviral evaluation of 4-fluoropyrazole-3-carboxamide nucleoside derivatives. ACTA ACUST UNITED AC 2008:617-8. [DOI: 10.1093/nass/nrn312] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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5
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Leroy F, Dukhan D, Durka M, Chaves D, Bragnier N, Storer R, Gosselin G. Synthesis of 2'-C-methyl-beta-D-ribofuranosylimidazo [4,5-d]-pyridazine derivatives (2-aza-3-deazapurine nucleoside analogues). Nucleosides Nucleotides Nucleic Acids 2005; 24:667-9. [PMID: 16248010 DOI: 10.1081/ncn-200060225] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In order to evaluate their antiviral properties, two imidazo[4,5-d]pyridazine 2'-C-methyl-beta-D-ribofuranonucleoside derivatives have been synthesized.
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Affiliation(s)
- F Leroy
- Laboratoire Coopératif Idenix-CNRS, Université Montpellier II, Montpellier Cedex 5, France
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6
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Abstract
Starting from 2-C-methyl-ribonolactone, 1,2,3,5-tetra-O-acetyl-2-C-methyl-4-thioribofuranose was synthesized and condensed with heterocyclic bases to afford 2-C-methyl-4'-thioribonucleosides.
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Affiliation(s)
- D Dukhan
- Laboratoire Coopératif Idenix-CNRS, Université Montpellier II, Montpellier Cedex 5, France
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7
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Meillon JC, Griffe L, Storer R, Gosselin G. Rapid access to 2'-branched-carbocyclic nucleosides and their 4'-epimers from 2-alkyl-cyclopentene-1-ones. Nucleosides Nucleotides Nucleic Acids 2005; 24:695-9. [PMID: 16248017 DOI: 10.1081/ncn-200060271] [Citation(s) in RCA: 5] [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] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
2-Methyl-2-cyclopentene-1-one was used as starting material in a novel route toward 2'-branchedcarbocyclic nucleosides. This methodology was efficiently adapted to the preparation of 4'-epicarbocycles. A series of this new class of molecules was synthesized as potential antiviral compounds.
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Affiliation(s)
- J C Meillon
- Laboratoire Coopératif Idenix-CNRS, Université Montpellier II, Montpellier Cedex 5, France
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8
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Dukhan D, Leroy F, Peyronnet J, Bosc E, Chaves D, Durka M, Storer R, La Colla P, Seela F, Gosselin G. Synthesis of 5-aza-7-deazaguanine nucleoside derivatives as potential anti-flavivirus agents. Nucleosides Nucleotides Nucleic Acids 2005; 24:671-4. [PMID: 16248011 DOI: 10.1081/ncn-200060228] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Coupling suitable sugars (D- or L-ribofuranose, 2' or 3-deoxysugar, branched sugars) with 2-aminoimidazo[1,2-a]-s-triazin-4-one was carried out using the different reaction conditions: 1) condensation in the presence of sodium hydride; or 2) condensation using Vorbrüggen's methods. The 5-aza- 7-deazaguanine nucleoside analogues obtained were evaluated in cell culture experiments for the inhibition of the replication of a number of RNA viruses, including BVDV, YFV, and WNV.
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Affiliation(s)
- D Dukhan
- Laboratoire Coopératif Idenix-CNRS, Université Montpellier II, Montpellier Cedex 5, France
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9
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Pierra C, Benzaria S, Amador A, Moussa A, Mathieu S, Storer R, Gosselin G. Nm 283, an efficient prodrug of the potent anti-HCV agent 2'-C-methylcytidine. Nucleosides Nucleotides Nucleic Acids 2005; 24:767-70. [PMID: 16248033 DOI: 10.1081/ncn-200060112] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In order to improve the oral bioavailability of 2-C-methylcytidine, a potent anti-HCV agent, the corresponding 3'-O-L-valinyl ester derivative (NM 283) has been synthesized Based on its ease of synthesis and its physicochemical properties, NM 283 has emerged as a promising antiviral drug for treatment of chronic HCV infection.
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Affiliation(s)
- C Pierra
- Laboratoire Coopératif Idenix-CNRS, Université Montpellier II, Montpellier Cedex 5, France
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10
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Tsakadze EL, Ostrikov KN, Xu S, Jones IR, Storer R, Yu MY, Lee S. Effect of an internal rotating current on low-frequency inductively coupled plasmas. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 63:046402. [PMID: 11308951 DOI: 10.1103/physreve.63.046402] [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] [Subscribe] [Scholar Register] [Received: 09/11/2000] [Indexed: 05/23/2023]
Abstract
The effect of an internal low-frequency rotating current on inductively coupled plasmas in cylindrical chambers is studied. The electromagnetic field structure, power density distribution, the plasma density, and the operating regimes of the discharge are investigated using electrodynamic, power, and particle balance equations. It is shown that the rotating current sheet can dramatically improve the uniformity of the electromagnetic fields and the power transferred to the plasma electrons from that of conventional low-frequency inductively coupled plasma sources with external flat spiral inductive coils.
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Affiliation(s)
- E L Tsakadze
- Plasma Processing Laboratory, NIE, Nanyang Technological University, 1 Nanyang Walk, 637616 Singapore, Republic of Singapore
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11
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Gulezian D, Jacobson-Kram D, McCullough CB, Olson H, Recio L, Robinson D, Storer R, Tennant R, Ward JM, Neumann DA. Use of transgenic animals for carcinogenicity testing: considerations and implications for risk assessment. Toxicol Pathol 2000; 28:482-99. [PMID: 10862569 DOI: 10.1177/019262330002800320] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [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: 11/16/2022]
Abstract
Advances in genetic engineering have created opportunities for improved understanding of the molecular basis of carcinogenesis. Through selective introduction, activation, and inactivation of specific genes, investigators can produce mice of unique genotypes and phenotypes that afford insights into the events and mechanisms responsible for tumor formation. It has been suggested that such animals might be used for routine testing of chemicals to determine their carcinogenic potential because the animals may be mechanistically relevant for understanding and predicting the human response to exposure to the chemical being tested. Before transgenic and knockout mice can be used as an adjunct or alternative to the conventional 2-year rodent bioassay, information related to the animal line to be used, study design, and data analysis and interpretation must be carefully considered. Here, we identify and review such information relative to Tg.AC and rasH2 transgenic mice and p53+/- and XPA-/- knockout mice, all of which have been proposed for use in chemical carcinogenicity testing. In addition, the implications of findings of tumors in transgenic and knockout animals when exposed to chemicals is discussed in the context of human health risk assessment.
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Affiliation(s)
- D Gulezian
- Taconic Farms, Inc, Madison, Connecticut 06443, USA
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12
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Abstract
The use of solution phase techniques has been explored as an alternative to solid-phase chemistry approaches for the preparation of arrays of compounds in the drug discovery process. Solution-phase work is free from some of the constraints of solid-phase approaches but has disadvantages with respect to purification. This article will also illustrate some of the advances made in recent years in solution phase array chemistry including using supported reagents and simple extractive protocols for the effective preparation of high quality samples.
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Affiliation(s)
- D M Coe
- Glaxo Wellcome Research and Development, Medicines Research Centre, Stevenage, U.K
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13
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Storer R, Ashton CJ, Baxter AD, Hann MM, Marr CL, Mason AM, Mo CL, Myers PL, Noble SA, Penn CR, Weir NG, Woods JM, Coe PL. The synthesis and antiviral activity of 4-fluoro-1-beta-D-ribofuranosyl-1H-pyrazole-3-carboxamide. Nucleosides Nucleotides 1999; 18:203-16. [PMID: 10067273 DOI: 10.1080/15257779908043068] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A novel fluoropyrazole ribonucleoside has been shown to have significant anti-influenza activity in vitro. The compound is compared and contrasted with the structurally-related compound ribavirin in attempts to identify factors having significant bearing on the mode of action of both compounds.
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Affiliation(s)
- R Storer
- GlaxoWellcome Research and Development, Medicines Research Centre, Stevenage, Hertfordshire, UK
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14
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Abstract
Forty-four patients, most of whom had previous experience of soft linings, had a total of 62 soft linings placed in their lower complete dentures:32 of the silicone-based Molloplast-band 30 of the heat-cured plasticised acrylic Palasiv 62. Linings were evaluated at insertion and then at 3-monthly intervals. Surface changes and the reasons for lining replacement were used to assess the clinical serviceability of the linings. The median survival time of Molloplast-b linings was significantly greater than that of Palasiv 62, whose performance was inadequate with frequent failure due to surface deterioration, with and without a failure of bonding. Denture fracture was the most common cause of lining failure for Molloplast-b and occurred more frequently than with Palasiv 62. Fading and lining discolouration was commonly observed for both materials.
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Affiliation(s)
- N J Jepson
- Department of Restorative Dentistry, Dental School, University of Newscastle upon Tyne
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15
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Mahmoudian M, Baines BS, Drake CS, Hale RS, Jones P, Piercey JE, Montgomery DS, Purvis IJ, Storer R, Dawson MJ. Enzymatic production of optically pure (2'R-cis)-2'-deoxy-3'-thiacytidine (3TC, lamivudine): a potent anti-HIV agent. Enzyme Microb Technol 1993; 15:749-55. [PMID: 7764073 DOI: 10.1016/0141-0229(93)90005-m] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [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: 01/27/2023]
Abstract
Although equipotent in terms of antiviral activity, the two enantiomers of 2'-deoxy-3'-thiacytidine (BCH 189) differ markedly in their cytotoxicity. (2'R-cis)-2'-deoxy-3'-thiacytidine (3TC) is substantially less toxic than its optical antipode, and is undergoing development for the therapy of HIV infection. Cytidine deaminase from Escherichia coli is shown here to deaminate 2'-deoxy-3'-thiacytidine enantioselectively to leave 3TC essentially optically pure. This reaction has been used to develop a process for production of 3TC in multikilogram amounts. The production of cytidine deaminase was enhanced by strain improvement, fermentation development, and finally by cloning and overexpression of the gene. The enzyme was immobilized on Eupergit-C, which allowed it to be reused many times. The biotransformation conditions were optimized so that the best use could be made of the catalyst. A robust scaleable product isolation process was developed to yield the crystalline product. Overall, yields through the resolution process of 76% were obtained. All aspects of this process are capable of substantial further scaleup with only minor modifications.
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Affiliation(s)
- M Mahmoudian
- Department of Natural Products Discovery, Glaxo Group Research Ltd, Greenford, Middlesex, England
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16
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Abstract
The viscoelastic properties of a widely used temporary soft lining material have been monitored in vivo and in vitro using a force distance probe. Over a period of 8 weeks' clinical use, Coe Soft demonstrated a significant and continued reduction in compliance with time, the reduction being particularly rapid over the first week. These changes were not associated with a reduction in measured lining thickness for which significant changes were not found. In vitro immersion in water, saline or artificial saliva was characterized by a rapid and significant reduction in compliance values over the first week. Further continued reductions in compliance values were only observed in artificial saliva over 8 weeks, and on prolonged immersion in distilled water over 96 weeks. All reductions in compliance were significantly less than those seen clinically.
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Affiliation(s)
- N J Jepson
- Department of Prosthodontics, Dental School, University of Newcastle upon Tyne, UK
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17
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Abstract
Denture soft lining materials are widely used in prosthetic dentistry. Their success has been attributed to their softness and resilience, properties described by their viscoelasticity. Though these properties have been extensively investigated in laboratory studies, clinical studies have been limited. The viscoelastic properties of the temporary soft lining material Coe Soft and the permanent soft lining materials Palasiv 62 and Molloplast-B have been studied using a force/distance probe whereby penetration was measured against time under constant stress. Derived values of an initial and time-dependent compliance has allowed a quantitative in vivo and in vitro assessment of freshly prepared samples of each test material and comparison between materials. The baseline behaviour of each test material in response to the test regimen was similar for both clinical and laboratory specimens. Three types of behaviour could be identified: (i) constant strain in which penetration was clearly less than specimen thickness--elastic behaviour (Molloplast-B); (ii) constant strain in which the penetration was equal or nearly equal to specimen thickness--apparent elastic behaviour (Coe Soft); (iii) strain which increased with time of load application--viscoelastic behaviour (Palasiv 62). The mean and range of baseline clinical thickness for Coe Soft was approximately half that seen for the permanent soft lining materials. There was a much smaller range in the baseline compliance of all materials than might have been anticipated from a knowledge of their relative softness.
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Affiliation(s)
- N J Jepson
- Department of Prosthodontics, Dental School, University of Newcastle upon Tyne, UK
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18
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Abstract
Age-related changes in the viscoelasticity of an acrylic-based (Palasiv 62) and silicone (Molloplast-B) permanent soft lining material were evaluated in parallel clinical and laboratory longitudinal studies using a force/distance probe. Changes in the viscoelastic properties of Palasiv 62 in clinical use were characterized by a significant and continued reduction in both initial and delayed compliance. That is, the material became harder whilst still retaining the underlying pattern of viscoelasticity seen at baseline. Laboratory immersion in distilled water resulted in significant reductions in compliance values. These reductions were cumulatively similar to those seen clinically but did not occur as rapidly. There was evidence of small, continued reductions in the measured thickness of clinical linings of Palasiv 62. The clinical and laboratory compliance of Molloplast-B remained stable over time. Ageing did not affect the essential elasticity of this material.
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Affiliation(s)
- N J Jepson
- Department of Prosthodontics, Dental School, University of Newcastle upon Tyne, UK
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20
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Humber DC, Cammack N, Coates JA, Cobley KN, Orr DC, Storer R, Weingarten GG, Weir MP. Penicillin derived C2-symmetric dimers as novel inhibitors of HIV-1 proteinase. J Med Chem 1992; 35:3080-1. [PMID: 1501235 DOI: 10.1021/jm00094a024] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- D C Humber
- Department of Medicinal Chemistry II, Glaxo Group Research Limited, Greenford, Middlesex, United Kingdom
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21
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Myles PS, Storer R, Millar C. Haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery: good versus poor myocardial function. Anaesth Intensive Care 1992; 20:21-7. [PMID: 1609936 DOI: 10.1177/0310057x9202000104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 12/27/2022]
Abstract
We measured haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery utilizing a standard anaesthetic technique of fentanyl 15 mcg/kg nitrous oxide 50%/enflurane 1%. We divided 22 patients preoperatively into two groups according to standard criteria: good and poor myocardial function. Regression lines could be drawn illustrating the relationship of cardiac output and uptake (at 1 minute: r = -0.56, P less than 0.01; at 5 minutes: r = -0.43, P less than 0.05; at 30 minutes: r = -0.31, P = 0.08). Although patients with poor myocardial function had decreased uptake of enflurance (approximately 10-20%), this did not reach statistical significance. Fentanyl/nitrous oxide/enflurane anaesthesia provided stable haemodynamics, even in patients with poor myocardial function. Both groups had a shunt fraction of approximately 10% and an arterial: end-tidal carbon dioxide difference of approximately 3-4 mmHg.
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Affiliation(s)
- P S Myles
- Anaesthetic Department, Royal Perth Hospital, Western Australia
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22
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Coates JA, Cammack N, Jenkinson HJ, Mutton IM, Pearson BA, Storer R, Cameron JM, Penn CR. The separated enantiomers of 2'-deoxy-3'-thiacytidine (BCH 189) both inhibit human immunodeficiency virus replication in vitro. Antimicrob Agents Chemother 1992; 36:202-5. [PMID: 1590690 PMCID: PMC189255 DOI: 10.1128/aac.36.1.202] [Citation(s) in RCA: 241] [Impact Index Per Article: 7.5] [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: 12/27/2022] Open
Abstract
Racemic 2'-deoxy-3'-thiacytidine (BCH 189) is a dideoxycytidine analog having a sulfur atom in place of the 3' carbon. The enantiomers of BCH 189 have been resolved and found to be equipotent in antiviral activity against human immunodeficiency virus types 1 and 2. However, the (-)-enantiomer (3TC) is considerably less cytotoxic than the (+)-enantiomer.
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Affiliation(s)
- J A Coates
- Department of Virology, Glaxo Group Research Ltd., Greenford, Middlesex, United Kingdom
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23
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Coe D, Hilpert H, Noble S, Peel M, Roberts S, Storer R. Synthesis of some mimics of nucleoside triphosphates. Antiviral Res 1991. [DOI: 10.1016/0166-3542(91)90100-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Wang Y, Fleet G, Wilson F, Storer R, Wallis C, Doherty O, Watkin D, Vogt K, Witty D, Peach J. Oxetane nucleosides with fluorine and azide substitutents: nucleophilic displacements on an oxetane ring. Tetrahedron Lett 1991. [DOI: 10.1016/s0040-4039(00)74302-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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25
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Chadwick RG, McCabe JF, Walls AW, Mitchell HL, Storer R. Comparison of a novel photogrammetric technique and modified USPHS criteria to monitor the wear of restorations. J Dent 1991; 19:39-45. [PMID: 2016426 DOI: 10.1016/0300-5712(91)90036-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [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: 12/29/2022] Open
Abstract
This paper describes monitoring the wear of restorations borne by partial dentures over a 12 months period using a novel photogrammetric technique and modified United States Public Health Service (USPHS) criteria. The performance of Class II restorations of Dispersalloy was compared with that of similar restorations of either KetacFil or Occlusin. The photogrammetric technique highlighted differences in performance not detected by the modified USPHS criteria. It is concluded that the photogrammetric technique should prove valuable in the in vivo assessment of the performance of restorative materials but that further refinement of the method is required particularly with regard to the orientation of replicas for sequential measurements.
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26
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Coates JA, Inggall HJ, Pearson BA, Penn CR, Storer R, Williamson C, Cameron JM. Carbovir: the (-) enantiomer is a potent and selective antiviral agent against human immunodeficiency virus in vitro. Antiviral Res 1991; 15:161-8. [PMID: 1677557 DOI: 10.1016/0166-3542(91)90033-n] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [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: 12/28/2022]
Abstract
In this paper we describe the in vitro antiviral activity of the (-) enantiomer of carbocyclic 2',3'-deoxydidehydroguanosine, (-) carbovir, a nucleoside analogue that has selective and potent anti-HIV activity in a series of lymphocyte culture systems. The cellular cytotoxicity of this compound has also been evaluated in a number of systems and compared to the saturated dideoxynucleoside analogues AZT and ddC.
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Affiliation(s)
- J A Coates
- Department of Virology, Glaxo Group Research Limited, Greenford, U.K
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27
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Abstract
The effects of various storage media [distilled water, lactate (pH 4.0), and citrate (pH 6.0) buffers] upon the hardness and wear factor values of three composites [Occlusin (O), P-30 (P), and Fulfil (F)] were studied. Over the one-year storage period, the hardness of all three materials stored in citrate buffer was unchanged. In the case of P in water and all materials stored in lactate buffer, a reduction was observed. There was no significant difference (P greater than 0.05) between the wear factors of specimens after one year or one week of water storage. Specimens of F stored in citrate buffer had a wear factor (P less than 0.01) higher than that of those stored in water. The other materials were not affected by storage in the lactate or citrate buffers. A reduction in surface hardness for some materials did not result in an increase in wear rate. This indicates that the softening effect was limited to a thin surface layer. Although not significant in vitro, this effect would probably increase the rate of in vivo wear, since the softened material would be lost, exposing a fresh surface to further attack. This would adversely prejudice the material's long-term clinical durability by impairing its resistance to abrasion.
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Affiliation(s)
- R G Chadwick
- Department of Conservative Dentistry, Dental School, The University, Dundee, UK
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28
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Witty D, Fleet G, Vogt K, Wilson F, Wang Y, Storer R, Myers P, Wallis C. Ring contraction of 2-o-trifluoromethanesulphonates of α-hydroxy-γ-lactones to oxetane carboxylic esters. Tetrahedron Lett 1990. [DOI: 10.1016/s0040-4039(00)97734-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Wilson F, Fleet G, Witty D, Vogt K, Wang Y, Storer R, Myers P, Wallis C. Synthesis of the oxetane nucleosides α- an β-noroxetanocin. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/s0957-4166(00)80540-6] [Citation(s) in RCA: 14] [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] [Indexed: 10/18/2022]
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Elliott R, Fleet G, Vogt K, Wilson F, Wang Y, Witty D, Storer R, Myers P, Wallis C. Attempted ring contraction of α-triflates of 3-azido- and 3-fluoro-γ-lactones to oxetanes. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/s0957-4166(00)82381-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chadwick RG, McCabe JF, Walls AW, Storer R. The effect of placement technique upon the compressive strength and porosity of a composite resin. J Dent 1989; 17:230-3. [PMID: 2621273 DOI: 10.1016/0300-5712(89)90171-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
This paper examines the effect of two placement techniques upon the compressive strength and level of porosity of specimens of a composite resin. Those specimens prepared by a condensation technique had a significantly lower mean compressive strength (P less than 0.05) and value of Weibull modulus (P less than 0.05) than specimens prepared using a smearing technique. No significant differences in the overall mean percentage area occupied by porosity and mean number of pores were demonstrated (P greater than 0.05) between the two placement techniques. Specimens prepared using the smearing technique, however, had significantly smaller mean maximum pore diameters (P less than 0.05) than those prepared using the condensation technique. It is therefore desirable when placing composite resins to reduce to a minimum handling procedures that are likely to influence the levels of porosity within the material.
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Storer R. Solution of prosthodontic problems through new materials. Ann R Coll Surg Engl 1971; 48:33-4. [PMID: 4929342 PMCID: PMC2387840] [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: 01/13/2023] Open
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Storer R. Age-old problems in prosthodontics. Br Dent J 1970; 129:293-4. [PMID: 5272503 DOI: 10.1038/sj.bdj.4802574] [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: 01/14/2023]
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Storer R. Gingival care in prosthetic dentistry. Dent Pract Dent Rec 1969; 19:187-93. [PMID: 5250474] [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: 01/14/2023]
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Storer R, Bowman AJ. An unusual factor in disharmony of the masticatory system. Br Dent J 1969; 126:80-1. [PMID: 5253448] [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: 01/14/2023]
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Coggon P, McPhail AT, Storer R, Young DW. The structure and absolute configuration of fraxinellone, a biogenetically intriguing terpenoid from Dictamnus albus L. ACTA ACUST UNITED AC 1969. [DOI: 10.1039/c29690000828] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Storer R. Geriatric dentistry. Br Dent J 1966; 121:547-52. [PMID: 5332684] [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: 01/14/2023]
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