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Buchan A, Neidle EL, Moran MA. Diversity of the ring-cleaving dioxygenase gene pcaH in a salt marsh bacterial community. Appl Environ Microbiol 2001; 67:5801-9. [PMID: 11722937 PMCID: PMC93374 DOI: 10.1128/aem.67.12.5801-5809.2001] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Degradation of lignin-related aromatic compounds is an important ecological process in the highly productive salt marshes of the southeastern United States, yet little is known about the mediating organisms or their catabolic pathways. Here we report the diversity of a gene encoding a key ring-cleaving enzyme of the beta-ketoadipate pathway, pcaH, amplified from bacterial communities associated with decaying Spartina alterniflora, the salt marsh grass that dominates these coastal systems, as well as from enrichment cultures with aromatic substrates (p-hydroxybenzoate, anthranilate, vanillate, and dehydroabietate). Sequence analysis of 149 pcaH clones revealed 85 unique sequences. Thirteen of the 53 amino acid residues compared were invariant in the PcaH proteins, suggesting that these residues have a required catalytic or structural function. Fifty-eight percent of the clones matched sequences amplified from a collection of 36 bacterial isolates obtained from seawater, marine sediments, or senescent Spartina. Fifty-two percent of the pcaH clones could be assigned to the roseobacter group, a marine lineage of the class alpha-Proteobacteria abundant in coastal ecosystems. Another 6% of the clones matched genes retrieved from isolates belonging to the genera Acinetobacter, Bacillus, and Stappia, and 42% of the clones could not be assigned to a cultured bacterium based on sequence identity. These results suggest that the diversity of the genes encoding a single step in aromatic compound degradation in the coastal marsh examined is high.
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Buchan A, Alber M, Hodson RE. Strain-specific differentiation of environmental Escherichia coli isolates via denaturing gradient gel electrophoresis (DGGE) analysis of the 16S-23S intergenic spacer region. FEMS Microbiol Ecol 2001; 35:313-321. [PMID: 11311442 DOI: 10.1111/j.1574-6941.2001.tb00817.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Denaturing gradient gel electrophoresis (DGGE) was applied to the 16S-23S rRNA intergenic spacer region (ISR) as a means to evaluate strain level differences in Escherichia coli. The ISRs of 81 environmental E. coli isolates obtained from bovine, poultry, and human sources yielded a total of 41 unique DGGE banding patterns, with identical patterns and common bands within each source and no overlapping patterns among sources. An additional 51 isolates from two nearby streams yielded 45 unique banding patterns with no overlap between sites. However, two of the isolates from the streams had identical banding patterns to those from two of the source isolates, resulting in a total of 84 unique DGGE banding patterns out of 132 isolates identified in this study. These results revealed high diversity among environmental E. coli isolates, which made it difficult to unambiguously ascribe strains found in water samples to specific host organisms.
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Buchan A. Strain-specific differentiation of environmental Escherichia coli isolates via denaturing gradient gel electrophoresis (DGGE) analysis of the 16S–23S intergenic spacer region. FEMS Microbiol Ecol 2001. [DOI: 10.1016/s0168-6496(01)00109-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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56
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Munro CA, Winter K, Buchan A, Henry K, Becker JM, Brown AJ, Bulawa CE, Gow NA. Chs1 of Candida albicans is an essential chitin synthase required for synthesis of the septum and for cell integrity. Mol Microbiol 2001; 39:1414-26. [PMID: 11251855 DOI: 10.1046/j.1365-2958.2001.02347.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
CaCHS1 of the fungal pathogen Candida albicans encodes an essential chitin synthase that is required for septum formation, viability, cell shape and integrity. The CaCHS1 gene was inactivated by first disrupting one allele using the ura-blaster protocol, then placing the remaining allele under the control of the maltose-inducible, glucose-repressible MRP1 promoter. Under repressing conditions, yeast cell growth continued temporarily, but daughter buds failed to detach from parents, resulting in septumless chains of cells with constrictions defining contiguous compartments. After several generations, a proportion of the distal compartments lysed. The conditional Deltachs1 mutant also failed to form primary septa in hyphae; after several generations, growth stopped, and hyphae developed swollen balloon-like features or lysed at one of a number of sites including the hyphal apex and other locations that would not normally be associated with septum formation. CHS1 therefore synthesizes the septum of both yeast and hyphae and also maintains the integrity of the lateral cell wall. The conditional mutant was avirulent under repressing conditions in an experimental model of systemic infection. Because this gene is essential in vitro and in vivo and is not present in humans, it represents an attractive target for the development of antifungal compounds.
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Mott BD, Canver CC, Nazeer T, Buchan A, Ilves R. Staged resection of bilateral pleuropulmonary blastoma in a two-month old girl. THE JOURNAL OF CARDIOVASCULAR SURGERY 2001; 42:135-7. [PMID: 11292922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Pleuropulmonary blastoma is a rare unilateral intrathoracic tumor of childhood. We report an unusual case of bilateral pleuropulmonary blastoma in a two-month old girl who underwent staged thoracotomies for complete wedge resection of both neoplasm. She remains well and tumor free two years after the operation.
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Buchan A, Collier LS, Neidle EL, Moran MA. Key aromatic-ring-cleaving enzyme, protocatechuate 3,4-dioxygenase, in the ecologically important marine Roseobacter lineage. Appl Environ Microbiol 2000; 66:4662-72. [PMID: 11055908 PMCID: PMC92364 DOI: 10.1128/aem.66.11.4662-4672.2000] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aromatic compound degradation in six bacteria representing an ecologically important marine taxon of the alpha-proteobacteria was investigated. Initial screens suggested that isolates in the Roseobacter lineage can degrade aromatic compounds via the beta-ketoadipate pathway, a catabolic route that has been well characterized in soil microbes. Six Roseobacter isolates were screened for the presence of protocatechuate 3,4-dioxygenase, a key enzyme in the beta-ketoadipate pathway. All six isolates were capable of growth on at least three of the eight aromatic monomers presented (anthranilate, benzoate, p-hydroxybenzoate, salicylate, vanillate, ferulate, protocatechuate, and coumarate). Four of the Roseobacter group isolates had inducible protocatechuate 3, 4-dioxygenase activity in cell extracts when grown on p-hydroxybenzoate. The pcaGH genes encoding this ring cleavage enzyme were cloned and sequenced from two isolates, Sagittula stellata E-37 and isolate Y3F, and in both cases the genes could be expressed in Escherichia coli to yield dioxygenase activity. Additional genes involved in the protocatechuate branch of the beta-ketoadipate pathway (pcaC, pcaQ, and pobA) were found to cluster with pcaGH in these two isolates. Pairwise sequence analysis of the pca genes revealed greater similarity between the two Roseobacter group isolates than between genes from either Roseobacter strain and soil bacteria. A degenerate PCR primer set targeting a conserved region within PcaH successfully amplified a fragment of pcaH from two additional Roseobacter group isolates, and Southern hybridization indicated the presence of pcaH in the remaining two isolates. This evidence of protocatechuate 3, 4-dioxygenase and the beta-ketoadipate pathway was found in all six Roseobacter isolates, suggesting widespread abilities to degrade aromatic compounds in this marine lineage.
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Skinner GR, Billstrom M, Randall S, Buchan A, Davies J, Ahmad A. Antiviral efficacy of disinfectant solution MRI-1. Intervirology 1999; 41:238-43. [PMID: 10325533 DOI: 10.1159/000024945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Disinfectant MRI-1 was prepared by dissolution of non-ionic and ionic detergent in ethanol. The disinfectant inactivated extracellular and intracellular enveloped and non-enveloped viruses including herpes viruses, influenza A and human immunodeficiency disease virus in suspension or on surfaces by pre-exposure or post-exposure to the disinfectant; in addition, cells were disabled as potential hosts for viral infection using concentrations of MRI-1 which were 50-fold less than the operative concentration for disinfection. There was no evidence of in vitro mutagenicity using Salmonella typhimurium or sensitization or other adverse effect in a guinea pig model or in human subjects.
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Dumbell KR, Harper L, Buchan A, Douglass NJ, Bedson HS. A variant of variola virus, characterized by changes in polypeptide and endonuclease profiles. Epidemiol Infect 1999; 122:287-90. [PMID: 10355794 PMCID: PMC2809618 DOI: 10.1017/s0950268899002150] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A variant of variola virus is described which produces a late polypeptide of 25 kDa instead of one of 27 kDa and which has an additional endonuclease cleavage site for SalI in the viral DNA. These markers were shown to be genetically independent and to characterize 14 of the 48 variola strains which were examined. The variant strains were isolated from smallpox outbreaks originating in or from Pakistan between 1961 and 1974 and also from two cases at a Mission Hospital in Vellore, India in 1964. No variant strains were found among 9 other isolates from cases of variola major occurring in other parts of India or in Bangladesh, nor among 4 isolates from Indonesia, 15 from Africa or 6 isolates of variola minor.
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Evans JS, Lock KP, Levine BA, Champness JN, Sanderson MR, Summers WC, McLeish PJ, Buchan A. Herpesviral thymidine kinases: laxity and resistance by design. J Gen Virol 1998; 79 ( Pt 9):2083-92. [PMID: 9747715 DOI: 10.1099/0022-1317-79-9-2083] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Norris JW, Buchan A, Cote R, Hachinski V, Phillips SJ, Shuaib A, Silver F, Simard D, Teal P. Canadian guidelines for intravenous thrombolytic treatment in acute stroke. A consensus statement of the Canadian Stroke Consortium. Neurol Sci 1998; 25:257-9. [PMID: 9706731 DOI: 10.1017/s0317167100034120] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The thromobolytic drug, tissue plasminogen activator (tPA) has been approved in the United States for the treatment of acute ischemic stroke amid controversy and concern about the balance of risk and benefit. The Canadian Stroke Consortium (CSC), a national network of neurologists who collaborate on joint projects in stroke medicine, including clinical trials and consensus statements, has developed guidelines for the use of tPA in Canada. METHODS AND RESULTS The CSC Board of Directors wrote a preliminary report based on existing publications, including randomized drug trials and the report of a special committee struck by the Stroke Council of the American Heart Association. This draft was circulated to the CSC membership-at-large for suggestions or amendments, to produce this final draft. CONCLUSIONS The present guidelines have been devised to represent a Canadian viewpoint of management. The Health Protection Branch of the Ministry of Health of Canada has not yet produced an evaluation. Further modification of these guidelines may be necessary when more data from clinical trials and experience with the drug become available.
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Goodyear HM, McLeish P, Buchan A, Harper JI. Virus characterization studies in eczema herpeticum. Br J Dermatol 1998; 138:545-6. [PMID: 9580819 DOI: 10.1046/j.1365-2133.1998.02143.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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64
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Evans JS, Lock KP, Levine BA, Champness JN, Sanderson MR, Summers WC, Buchan A. Structure-specificity features of HSV-1 thymidine kinases. Biochem Soc Trans 1997; 25:S621. [PMID: 9450049 DOI: 10.1042/bst025s621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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65
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Ling W, Lougheed M, Suzuki H, Buchan A, Kodama T, Steinbrecher UP. Oxidized or acetylated low density lipoproteins are rapidly cleared by the liver in mice with disruption of the scavenger receptor class A type I/II gene. J Clin Invest 1997; 100:244-52. [PMID: 9218499 PMCID: PMC508185 DOI: 10.1172/jci119528] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Oxidized low density lipoprotein (LDL) and acetyl LDL are recognized by the scavenger receptor class A type I/II (SR-AI/II) on macrophages and liver endothelial cells. Several investigators have suggested that there are additional receptors specific for oxidized LDL, but characterization of these alternate receptors for oxidized LDL and evaluation of their quantitative importance in uptake of oxidized LDL has been difficult because of overlapping ligand specificity with SR-AI/II. The purpose of this study was to determine the importance of SR-AI/II in the removal of modified LDL from the bloodstream in vivo. The clearance rate of oxidized LDL from plasma in normal mice was very rapid, and > 90% of injected dose was removed from the blood within 5 min. Clearance rates of oxidized LDL were equally high in SR-AI/II knockout mice, indicating that this receptor is not required for removal of oxidized LDL from plasma. Surprisingly, there was no difference in the clearance rate of acetyl LDL in wild-type and SR-AI/II knockout animals. The plasma clearance of radioiodinated acetyl LDL was almost fully blocked by a 50-fold excess of unlabeled acetyl LDL, but the latter only inhibited oxidized LDL clearance by approximately 5%. Both modified LDLs were cleared mostly by the liver, and there was no difference in the tissue distribution of modified LDL in control and knockout mice. Studies in isolated nonparenchymal liver cells showed that Kupffer cells accounted for most of the uptake of oxidized LDL. Extensively oxidized LDL and LDL modified by exposure to fatty acid peroxidation products were efficient competitors for the uptake of labeled oxidized LDL by SR-AI/II-deficient Kupffer cells, while acetyl LDL and malondialdehyde-modified LDL were relatively poor competitors.
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MESH Headings
- Animals
- Apolipoproteins/metabolism
- Cell Adhesion/physiology
- Cell Adhesion Molecules
- Cells, Cultured
- Copper Sulfate/pharmacology
- Endothelium/metabolism
- Kupffer Cells/metabolism
- Lipoproteins, LDL/blood
- Lipoproteins, LDL/metabolism
- Lipoproteins, LDL/pharmacokinetics
- Liver/metabolism
- Malondialdehyde/pharmacology
- Mice
- Mice, Knockout
- Oxidation-Reduction
- Receptors, Immunologic/metabolism
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Receptors, Oxidized LDL
- Receptors, Scavenger
- Scavenger Receptors, Class A
- Scavenger Receptors, Class E
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66
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Skinner GR, Turyk ME, Benson CA, Wilbanks GD, Heseltine P, Galpin J, Kaufman R, Goldberg L, Hartley CE, Buchan A. The efficacy and safety of Skinner herpes simplex vaccine towards modulation of herpes genitalis; report of a prospective double-blind placebo-controlled trial. Med Microbiol Immunol 1997; 186:31-6. [PMID: 9255764 DOI: 10.1007/s004300050043] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A randomised, placebo-controlled, multi-centre trial of intracellular subunit herpes simplex virus (HSV) type 1 vaccine NFU.Ac.HSV-1(S-)MRC (Skinner vaccine) was conducted at three medical centres in the United States. Subjects with documented herpes genitalis of at least 1-year duration and a history of six or more genital HSV recurrences in the 12 months prior to study entry were randomised to receive vaccine or placebo at 0, 1 and 2 months. Vaccination induced significant neutralising, enzyme-linked immunosorbent assay and lymphocyte transformation response to HSV-1 antigen. The frequency of recurrences was reduced in the vaccinated female patients at both 3 and 6 months following vaccination with an overall reduction in patients of both sexes which did not reach statistical significance. Recurrence severity was reduced as measured by decreased number of lesions and associated symptoms per recurrence (P = 0.04). The data suggest that clinical manifestations of latent HSV genital infection may be modified by therapeutic immunisation.
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Ladic L, Buchan A. Comparison of the spatial distribution of endopeptidase-24.11 with substance P, substance P receptor (NK-1r) and gastric efferent neurons in the dorsal vagal complex of the rat. Neurosci Lett 1997; 222:41-4. [PMID: 9121718 DOI: 10.1016/s0304-3940(97)13337-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The spatial location of neutral endopeptidase 24.11 (NEP) immunoreactivity was compared to that of substance P (SP), SP receptor (NK-1r) and identified gastric efferent neurons in the dorsal vagal complex in rat brainstem. The majority of NEP labeling was observed caudal to the obex. Neutral endopeptidase-immunoreactivity was associated with the central canal, ependyma and blood vessels, and surrounded the area postrema. A comparison of the results of immunocytochemical and retrograde tracing experiments demonstrated the absence of co-labeling of neurons or their process with NEP and either substance P or NK-1r. Furthermore, no NEP-immunoreactivity was observed in the vicinity of identified gastric efferents in the dorsal motor nucleus of the vagus. These results would suggest that NEP does not degrade SP in the vicinity of gastric efferent neurons.
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Skinner GR, Davies J, Ahmad A, McLeish P, Buchan A. An outbreak of herpes rugbiorum managed by vaccination of players and sociosexual contacts. J Infect 1996; 33:163-7. [PMID: 8945704 DOI: 10.1016/s0163-4453(96)92129-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An outbreak of herpes rugbiorum involved nine players including the scrum half and the full back. The infection was characterized by significant constitutional upset with decreased levels of general fitness and match performance for 1-4 months following the outbreak; one player had herpetic lesions on his right eyelid and corneum. Every infected player, 15 non-infected players and five sociosexual contacts received two vaccinations with intracellular subunit vaccine NFU. Ac. HSV-1 (S-MRC5). None of the players or contacts developed cutaneous herpetic recurrence during a follow-up period of 3 years; the player with ocular disease had one recurrence at 30 months following the original episode. These findings encourage consideration of prophylactic or post-exposure vaccination of participants in rugby or other contact sports with this or other appropriate herpes simplex vaccine.
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69
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Goodyear HM, Davies JA, McLeish P, Buchan A, Skinner GR, Winther M, Harper JI. Growth of herpes simplex type 1 on skin explants of atopic eczema. Clin Exp Dermatol 1996; 21:185-9. [PMID: 8914357 DOI: 10.1111/j.1365-2230.1996.tb00059.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In a novel approach to looking at why some children with atopic eczema are susceptible to cutaneous herpes simplex virus (HSV) infections, this study evaluates the hypothesis that HSV replicates more easily on eczematous than normal skin. Growth of HSV on eczematous skin explants was compared with growth on explants from three control groups (psoriasis, Darier's disease and normal skin) over a 2-day period. Growth of HSV was significantly less on normal skin than in atopic eczema, psoriasis and Darier's disease. Virus replicated more quickly, and grew to higher titre within 24h, in eczematous and psoriatic explants than in normal skin. A defect in skin barrier function and host defence factors including local cytokine secretion are discussed as possible mechanisms in causing the increased susceptibility of children with atopic eczema to HSV infection.
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70
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Durkin JP, Tremblay R, Buchan A, Blosser J, Chakravarthy B, Mealing G, Morley P, Song D. An early loss in membrane protein kinase C activity precedes the excitatory amino acid-induced death of primary cortical neurons. J Neurochem 1996; 66:951-62. [PMID: 8769854 DOI: 10.1046/j.1471-4159.1996.66030951.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Several lines of evidence indicate that a rapid loss of protein kinase C (PKC) activity may be important in the delayed death of neurons following cerebral ischemia. However, in primary neuronal cultures, cytotoxic levels of glutamate have been reported not to cause a loss in PKC as measured by immunoblot and conventional activity methods. This apparent contradiction has not been adequately addressed. In this study, the effects of cytotoxic levels of glutamate, NMDA, and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) on membrane PKC activity was determined in cortical neurons using an assay that measures only PKC that is active in isolated membranes, which can be used to differentiate active enzyme from that associated with membranes in an inactive state. A 15-min exposure of day 14-18 cortical neurons to 100 microM glutamate, AMPA, or NMDA caused a rapid and persistent loss in membrane PKC activity, which by 4 h fell to 30-50% of that in control cultures. However, the amount of enzyme present in these membranes remained unchanged during this period despite the loss in enzyme activity. The inactivation of PKC activity was confirmed by the fact that phosphorylation of the MARCKS protein, a PKC-selective substrate, was reduced in intact neurons following transient glutamate treatment. By contrast, activation of metabotropic glutamate receptors by trans-(1S,3R)-1-amino-1,3-cyclopentanedicarboxylic acid was not neurotoxic and induced a robust and prolonged activation of PKC activity in neurons. PKC inactivation by NMDA and AMPA was dependent on extracellular Ca2+, but less so on Na+, although cell death induced by these agents was dependent on both ions. The loss of PKC activity was likely effected by Ca2+ entry through specific routes because the bulk increase in intracellular free [Ca2+] effected by the Ca2+ ionophore ionomycin did not cause the inactivation of PKC. The results indicate that the pattern of PKC activity in neurons killed by glutamate, NMDA, and AMPA in vitro is consistent with that observed in neurons injured by cerebral Ischemia in vivo.
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Goodyear HM, McLeish P, Randall S, Buchan A, Skinner GR, Winther M, Rolland J, Morgan G, Harper JI. Immunological studies of herpes simplex virus infection in children with atopic eczema. Br J Dermatol 1996; 134:85-93. [PMID: 8745891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study examines the role of immune defence mechanisms in herpes simplex virus (HSV) infections in atopic eczema and whether impairment of these mechanisms explains the susceptibility of some children with atopic eczema to cutaneous HSV infections. Ten children with eczema herpeticum and 13 with atopic eczema and recurrent HSV infection affecting multiple skin sites were studied, together with relevant control groups. In all children with atopic eczema, in vitro lymphoproliferation in response to stimulation with concanavalin A (Con A) was significantly decreased and natural killer (NK) cells (CD16 + 56) were reduced compared with non-atopic controls. IL-2 receptors, a marker for lymphocyte activation, were decreased during the acute phase of eczema herpeticum, and for 1 month thereafter. A positive stimulation index (> 3) to HSV antigen, and high HSV IgG antibody titres measured by ELISA, Western blotting and neutralization assay, were seen in children with eczema herpeticum by 6 weeks, and also in children with atopic eczema and recurrent HSV infections. No evidence of an HSV-specific immune defect (either cell-mediated or humoral) was found in atopic eczema. Impairment of cell-mediated immunity in atopic eczema was suggested by the reduced response to Con A. It is likely that reduced numbers of circulating NK cells and a decrease in IL-2 receptors during early eczema herpeticum contribute to the susceptibility of children with atopic eczema to cutaneous HSV infections.
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72
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Davies J, Hallworth JA, McLeish P, Randall S, Martin BA, Buchan A, Skinner GR. Characterization and immunogenicity of a candidate subunit vaccine against varicella-zoster virus. Med Microbiol Immunol 1994; 183:105-17. [PMID: 7935160 DOI: 10.1007/bf00277161] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This study describes the properties of an inactivated subunit antigen preparation from varicella-zoster virus (VZV)-infected MRC-5 cells by treatment with detergent and formaldehyde, ultracentrifugation over sucrose and acetone precipitation. The method preserved the antigenicity of VZV proteins and several VZV-specific glycoproteins, while virus DNA was less than 20 pg/250 micrograms protein--a putative vaccine dose. The vaccine was immunogenic in rabbits and stimulated antibodies to the major capsid protein as well as to glycoproteins; an immunoprecipitin was shared with a known immune human serum. The preparation contained no infectious VZV with no evidence of side effects in a rabbit or in five human vaccinees during a follow-up period of 6-10 years.
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73
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Hartley CE, Buchan A, Randall S, Skinner GR, Osborne M, Tomkins LM. The effects of lithium and potassium on macromolecular synthesis in herpes simplex virus-infected cells. J Gen Virol 1993; 74 ( Pt 8):1519-25. [PMID: 8393911 DOI: 10.1099/0022-1317-74-8-1519] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
All herpes simplex virus (HSV) infected cell-specific polypeptides (ICSPs) were synthesized in the presence of lithium at a concentration (60 mM) inhibitory to the production of infectious virus. Yields of certain ICSPs were increased and others, in particular glycoprotein C, decreased. HSV DNA synthesis was completely inhibited; synthesis and in vitro activities of HSV DNA polymerase and thymidine kinase were decreased but to a degree insufficient to account for the complete inhibition of HSV DNA synthesis. HSV DNA synthesis was inhibited to an equivalent degree by either incubation with 60 mM-lithium or by potassium starvation; both procedures decreased intracellular potassium by an equivalent amount as adjudged by X-ray microanalysis. We conclude that lithium inhibits HSV DNA synthesis by displacement of potassium from a potassium-dependent biochemical reaction or by other physiological changes brought about by the loss of cellular potassium. The possibility that lithium also directly inhibits a virus replicative event cannot be excluded.
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74
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Pulsinelli W, Sarokin A, Buchan A. Antagonism of the NMDA and non-NMDA receptors in global versus focal brain ischemia. PROGRESS IN BRAIN RESEARCH 1993; 96:125-35. [PMID: 8392737 DOI: 10.1016/s0079-6123(08)63262-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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75
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Umana JP, Mutimer DJ, Shaw JC, McLeish PJ, Buchan A, Martin B, Neuberger JM, Elias E, McMaster P. Cytomegalovirus surveillance following liver transplantation: does it allow presymptomatic diagnosis of cytomegalovirus disease? Transplant Proc 1992; 24:2643-5. [PMID: 1334593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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