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Peng Y, Thrimawithana AH, Cooney JM, Jensen DJ, Espley RV, Allan AC. The proanthocyanin-related transcription factors MYBC1 and WRKY44 regulate branch points in the kiwifruit anthocyanin pathway. Sci Rep 2020; 10:14161. [PMID: 32843672 PMCID: PMC7447792 DOI: 10.1038/s41598-020-70977-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 08/07/2020] [Indexed: 12/11/2022] Open
Abstract
The groups of plant flavonoid metabolites termed anthocyanins and proanthocyanins (PA) are responsible for pigmentation in seeds, flowers and fruits. Anthocyanins and PAs are produced by a pathway of enzymes which are transcriptionally regulated by transcription factors (TFs) that form the MYB-bHLH-WD40 (MBW) complex. In this study, transcriptomic analysis of purple-pigmented kiwifruit skin and flesh tissues identified MYBC1, from subgroup 5 of the R2R3 MYB family, and WRKY44 (highly similar to Arabidopsis TTG2) as candidate activators of the anthocyanin pathway. Transient over-expression of MYBC1 and WRKY44 induced anthocyanin accumulation in tobacco leaves. Dual luciferase promoter activation assays revealed that both MYBC1 and WRKY44 were able to strongly activate the promoters of the kiwifruit F3'H and F3'5'H genes. These enzymes are branch points of the pathway which specifies the type of anthocyanin accumulated. Stable over-expression of MYBC1 and WRKY44 in kiwifruit calli activated the expression of F3'5'H and PA-related biosynthetic genes as well as increasing levels of PAs. These results suggest that while previously characterised anthocyanin activator MYBs regulate the overall anthocyanin biosynthesis pathway, the PA-related TFs, MYBC1 and WRKY44, more specifically regulate key branch points. This adds a layer of regulatory control that potentially balances anthocyanin and PA levels.
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Affiliation(s)
- Yongyan Peng
- School of Biological Sciences, University of Auckland, 3 Symonds Street, Auckland, New Zealand.
- The New Zealand Institute for Plant and Food Research Limited, 120 Mt Albert Road, Auckland, New Zealand.
| | - Amali H Thrimawithana
- The New Zealand Institute for Plant and Food Research Limited, 120 Mt Albert Road, Auckland, New Zealand
| | - Janine M Cooney
- The New Zealand Institute for Plant and Food Research Limited, Bisley Road, Ruakura, Hamilton, 3214, New Zealand
| | - Dwayne J Jensen
- The New Zealand Institute for Plant and Food Research Limited, Bisley Road, Ruakura, Hamilton, 3214, New Zealand
| | - Richard V Espley
- School of Biological Sciences, University of Auckland, 3 Symonds Street, Auckland, New Zealand
- The New Zealand Institute for Plant and Food Research Limited, 120 Mt Albert Road, Auckland, New Zealand
| | - Andrew C Allan
- School of Biological Sciences, University of Auckland, 3 Symonds Street, Auckland, New Zealand
- The New Zealand Institute for Plant and Food Research Limited, 120 Mt Albert Road, Auckland, New Zealand
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2
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Karr JJ, Antles HD, Audino JB, Bontoyan WR, Carlstrom AA, Conner D, DiPilla EJ, Ellis ND, Gentry GM, Gilmore PK, Hayes E, Helfant LJ, Jensen DJ, MacEachern GM, Bontoyan WR, Minyard JP, Topping A, Ullrich L, VandeLinde DC, Wargacki RE, Whitaker R. Gas-Liquid Chromatographic Method for the Analysis of Microencapsulated Ethyl Parathion and Methyl Parathion Insecticides: Collaborative Study. J AOAC Int 2020. [DOI: 10.1093/jaoac/63.5.999] [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: 11/13/2022]
Abstract
Abstract
The determination of ethyl parathion in Penncap-E insecticide was studied collaboratively by 14 laboratories. The assay of methyl parathion in Penncap-M insecticide was studied by 8 laboratories. The original method which was adopted official first action for methyl parathion specified dimethoate, which is currently classified as a suspected carcinogen, as the internal standard. The current collaborative efforts were conducted as a supplemental study to evaluate the performance of the new internal standard, bis-2-methoxyethyl phthalate, and to test the gas-liquid chromatographic method for microencapsulated ethyl parathion (internal standard, dibutyl phthalate). The method uses essentially the same grinding and extraction with acetonitrile as the original study. At the 20% methyl parathion level, the standard deviation within laboratories was 0.186%, and among laboratories, 0.737%. Two formulations of ethyl parathion at approximately 16 and 24% were analyzed in replicate on 2 days by the same analyst, and provided excellent agreement within laboratories as well as among laboratories. The standard deviation (pooled) within laboratories was 0.284% and among laboratories, 0.518%. The method has been adopted as official first action.
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Affiliation(s)
- James J Karr
- Pennwalt Corp., 900 First Ave, King of Prussia, PA 1940
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3
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Hurst RD, Lyall KA, Roberts JM, Perthaner A, Wells RW, Cooney JM, Jensen DJ, Burr NS, Hurst SM. Consumption of an Anthocyanin-Rich Extract Made From New Zealand Blackcurrants Prior to Exercise May Assist Recovery From Oxidative Stress and Maintains Circulating Neutrophil Function: A Pilot Study. Front Nutr 2019; 6:73. [PMID: 31192216 PMCID: PMC6548855 DOI: 10.3389/fnut.2019.00073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 05/01/2019] [Indexed: 12/21/2022] Open
Abstract
Aim: To evaluate blackcurrant anthocyanin-rich extract (BAE) consumption on time- and dose-dependent plasma anthocyanin bioavailability and conduct a pilot study to explore the potential effect of BAE in promoting recovery from exercise-induced oxidative stress, and maintenance of circulating neutrophil function. Methods: Time- and dose-dependent blackcurrant anthocyanin bioavailability was assessed using LC-MS in 12 participants over 6 h after the ingestion of a placebo or BAE containing 0.8, 1.6, or 3.2 mg/kg total anthocyanins. In a separate pilot intervention exercise trial, 32 participants consumed either a placebo or 0.8, 1.6, or 3.2 mg/kg BAE (8 individuals per group), and then 1 h later performed a 30 min row at 70% VO2max. Blood was collected during the trial for oxidative, antioxidant, inflammatory, and circulating neutrophil status. Results: Consumption of BAE caused a time- and dose-dependent increase in plasma anthocyanins, peaking at 2 h after ingestion of 3.2 mg/kg BAE (217 ± 69 nM). BAE consumed 1 h prior to a 30 min row had no effect on plasma antioxidant status but hastened the recovery from exercise-induced oxidative stress: By 2 h recovery, consumption of 1.6 mg/kg BAE prior to exercise caused a significant (P < 0.05) 34 and 32% decrease in post-exercise plasma oxidative capacity and protein carbonyl levels, respectively, compared to placebo. BAE consumption prior to exercise dose-dependently attenuated a small, yet significant (P < 0.01) transient 13 ± 2% decline in circulating neutrophils observed in the placebo group immediately post-exercise. Furthermore, the timed consumption of either 1.6 or 3.2 mg/kg BAE attenuated a 17 ± 2.4% (P < 0.05) decline in neutrophil phagocytic capability of opsonised FITC-Escherichia coli observed 6 h post-exercise in the placebo group. Similarly, a dose-dependent increase in neutrophil surface expression of complement receptor-3 complex (CR3, critical for effective phagocytosis of opsonised microbes), was observed 6 h post-exercise in both 1.6 and 3.2 mg/kg BAE intervention groups. Conclusions: Consumption of BAE (>1.6 mg/kg) 1 h prior to exercise facilitated recovery from exercise-induced oxidative stress and preserved circulating neutrophil function. This study provides data to underpin a larger study designed to evaluate the efficacy of timed BAE consumption on post-exercise recovery and innate immunity.
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Affiliation(s)
- Roger D Hurst
- The New Zealand Institute for Plant and Food Research Ltd., Palmerston North, New Zealand
| | - Kirsty A Lyall
- The New Zealand Institute for Plant and Food Research Ltd., Hamilton, New Zealand
| | - Joanna M Roberts
- AgResearch Ltd., The Hopkirk Research Institute, Palmerston North, New Zealand
| | - Anton Perthaner
- AgResearch Ltd., The Hopkirk Research Institute, Palmerston North, New Zealand
| | - Robyn W Wells
- The New Zealand Institute for Plant and Food Research Ltd., Hamilton, New Zealand
| | - Janine M Cooney
- The New Zealand Institute for Plant and Food Research Ltd., Hamilton, New Zealand
| | - Dwayne J Jensen
- The New Zealand Institute for Plant and Food Research Ltd., Hamilton, New Zealand
| | - Natalie S Burr
- The New Zealand Institute for Plant and Food Research Ltd., Palmerston North, New Zealand
| | - Suzanne M Hurst
- The New Zealand Institute for Plant and Food Research Ltd., Palmerston North, New Zealand
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4
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Larsen L, Joyce NI, Sansom CE, Cooney JM, Jensen DJ, Perry NB. Sweet Poisons: Honeys Contaminated with Glycosides of the Neurotoxin Tutin. J Nat Prod 2015; 78:1363-9. [PMID: 25993882 DOI: 10.1021/acs.jnatprod.5b00241] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Poisonings due to consumption of honeys containing plant toxins have been reported widely. One cause is the neurotoxin tutin, an oxygenated sesquiterpene picrotoxane, traced back to honeybees (Apis mellifera) collecting honeydew produced by passionvine hoppers (Scolypopa australis) feeding on sap of the poisonous shrub tutu (Coriaria spp.). However, a pharmacokinetic study suggested that unidentified conjugates of tutin were also present in such honeys. We now report the discovery, using ion trap LC-MS, of two tutin glycosides and their purification and structure determination as 2-(β-d-glucopyranosyl)tutin (4) and 2-[6'-(α-d-glucopyranosyl)-β-d-glucopyranosyl]tutin (5). These compounds were used to develop a quantitative triple quadrupole LC-MS method for honey analysis, which showed the presence of tutin (3.6 ± 0.1 μg/g honey), hyenanchin (19.3 ± 0.5), tutin glycoside (4) (4.9 ± 0.4), and tutin diglycoside (5) (4.9 ± 0.1) in one toxic honey. The ratios of 4 and 5 to tutin varied widely in other tutin-containing honeys. The glycosidation of tutin may represent detoxification by one or both of the insects involved in the food chain from plant to honey.
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Affiliation(s)
- Lesley Larsen
- †The New Zealand Institute for Plant and Food Research Limited, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Nigel I Joyce
- ‡The New Zealand Institute for Plant and Food Research Limited, Private Bag 4704, Christchurch, New Zealand
| | - Catherine E Sansom
- †The New Zealand Institute for Plant and Food Research Limited, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Janine M Cooney
- §The New Zealand Institute for Plant and Food Research Limited, Hamilton 3214, New Zealand
| | - Dwayne J Jensen
- §The New Zealand Institute for Plant and Food Research Limited, Hamilton 3214, New Zealand
| | - Nigel B Perry
- †The New Zealand Institute for Plant and Food Research Limited, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
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5
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Andre CM, Larsen L, Burgess EJ, Jensen DJ, Cooney JM, Evers D, Zhang J, Perry NB, Laing WA. Unusual immuno-modulatory triterpene-caffeates in the skins of russeted varieties of apples and pears. J Agric Food Chem 2013; 61:2773-9. [PMID: 23418665 DOI: 10.1021/jf305190e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Three triterpene-caffeates have been isolated from skins of a russeted apple cultivar "Merton Russet" and identified by LC-MS and NMR as betulinic acid-3-cis-caffeate, betulinic acid-3-trans-caffeate, and oleanolic acid-3-trans-caffeate. Betulinic acid-3-trans-caffeate and oleanolic acid-3-trans-caffeate were also found in russeted pear skins. These compounds have not been previously reported in apples or pears, or in any other foods. Their presence was related to suberized tissue as they were only found in russet portions of the partially russeted apple cultivar "Cox's Orange Pippin" and were not detected in the waxy apple cultivar "Royal Gala". High concentrations of betulinic acid-3-trans-caffeate were found in the bark of both "Merton Russet" and "Royal Gala" trees. The three triterpene-caffeates showed anti-inflammatory activity in vitro, inhibiting NF-κB activation with IC50's of 6-9 μM. Betulinic acid-3-trans-caffeate, the predominant compound in the apples, was immuno-modulatory at around 10 μM in the in vitro and ex vivo bioassays, boosting production of the pro-inflammatory cytokine TNFα in cells stimulated with bacterial lipopolysaccharides.
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Affiliation(s)
- Christelle M Andre
- The New Zealand Institute for Plant & Food Research Limited, Mt Albert Research Centre , Private Bag 92 169, Auckland 1142, New Zealand
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6
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Hurst SM, McGhie TK, Cooney JM, Jensen DJ, Gould EM, Lyall KA, Hurst RD. Blackcurrant proanthocyanidins augment IFN-gamma-induced suppression of IL-4 stimulated CCL26 secretion in alveolar epithelial cells. Mol Nutr Food Res 2010; 54 Suppl 2:S159-70. [PMID: 20229526 DOI: 10.1002/mnfr.200900297] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Epidemiological studies reveal that fruit consumption reduces the prevalence of airway inflammation and childhood asthma. In particular, blackcurrant polyphenolic extracts have been shown to alleviate lung inflammation. Since IL-4-stimulated eotaxin-3 (CCL26) secretion is a major factor in the continuous eosinophil recruitment observed in atopic asthma, our focus was to evaluate the effectiveness of blackcurrant polyphenolic compounds on CCL26 secretion in human alveolar epithelial cells. Our results indicate that a proanthocyanin-enriched blackcurrant extract (BC-P), but not anthocyanin-enriched blackcurrant extract suppressed both IL-4- and IL-13-stimulated CCL26 secretion in a dose-dependent manner. Furthermore pre-incubation of cells with BC-P caused a time-dependent suppression of IL-4-stimulated CCL26 secretion. Moreover, epigallocatechin (EGC), and to a lesser extent epicatechin, metabolites identified in the proanthocyanidin extract, suppressed IL-4-stimulated CCL26 secretion. EGC was also effective at reducing the cellular phosphorylated STAT-6/STAT-6 ratio. Furthermore, both BC-P and purified EGC potentiated the ability of IFN-gamma to suppress IL-4-stimulated CCL26 secretion. The progression of an allergic immune response is complex, identifying plant compounds that target specific cellular events and complement the body's own immune actions is important for the development of functional foods. Our findings support the potential for blackcurrant polyphenolic compounds to reduce eosinophil recruitment and alleviate eosinophilic-driven airway inflammation.
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Affiliation(s)
- Suzanne M Hurst
- Food Innovation portfolio, The Plant and Food Research Institute of New Zealand Ltd., Palmerston North, New Zealand.
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7
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Hurst RD, Wells RW, Hurst SM, McGhie TK, Cooney JM, Jensen DJ. Blueberry fruit polyphenolics suppress oxidative stress-induced skeletal muscle cell damage in vitro. Mol Nutr Food Res 2010; 54:353-63. [PMID: 19885847 DOI: 10.1002/mnfr.200900094] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Skeletal muscle damage can result from disease and unaccustomed or excessive exercise. Muscle dysfunction occurs via an increased level of reactive oxygen species and hence there is potential in antioxidants as amelioration strategies. We explored the putative benefit of fruit polyphenolic extracts in reducing the susceptibility of skeletal muscle cells to oxidative stress. Muscle myotubes were simultaneously challenged with fruit extracts (1-50 microg/mL) and calcium ionophore (A23187), hydrogen peroxide, or 2,4-dinitrophenol and damage monitored by release of cytosolic enzymes. A blueberry fruit extract displayed a potent and significant dose-dependent protective capacity. Evaluation of the protective capacity of anthocyanin sub-extracts of blueberry fruit and pure individual glycosides, with identification of extract polyphenolic components using MS, suggested that malvidin galactoside and/or glucoside were the active compounds. These in vitro data support the concept that blueberry fruits or derived foods rich in malvidin glycosides may be beneficial in alleviating muscle damage caused by oxidative stress. More research on the benefits of blueberry fruit consumption in human intervention studies is warranted.
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Affiliation(s)
- Roger D Hurst
- Functional Food and Health Group, New Zealand Institute for Plant and Food Research Ltd., Hamilton, New Zealand.
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8
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Lauren DR, Smith WA, Adaim A, Cooney JM, Wibisono R, Jensen DJ, Zhang J, Skinner MA. Chemical composition andin vitroanti-inflammatory activity of apple phenolic extracts and of their sub-fractions. Int J Food Sci Nutr 2009; 60 Suppl 7:188-205. [DOI: 10.1080/09637480902849203] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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9
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Rowan DD, Cao M, Lin-Wang K, Cooney JM, Jensen DJ, Austin PT, Hunt MB, Norling C, Hellens RP, Schaffer RJ, Allan AC. Environmental regulation of leaf colour in red 35S:PAP1 Arabidopsis thaliana. New Phytol 2009; 182:102-115. [PMID: 19192188 DOI: 10.1111/j.1469-8137.2008.02737.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
* High-temperature, low-light (HTLL) treatment of 35S:PAP1 Arabidopsis thaliana over-expressing the PAP1 (Production of Anthocyanin Pigment 1) gene results in reversible reduction of red colouration, suggesting the action of additional anthocyanin regulators. High-performance liquid chromatography (HPLC), liquid chromatography mass spectrometry (LCMS) and Affimetrix-based microarrays were used to measure changes in anthocyanin, flavonoids, and gene expression in response to HTLL. * HTLL treatment of control and 35S:PAP1 A. thaliana resulted in a reversible reduction in the concentrations of major anthocyanins despite ongoing over-expression of the PAP1 MYB transcription factor. Twenty-one anthocyanins including eight cis-coumaryl esters were identified by LCMS. The concentrations of nine anthocyanins were reduced and those of three were increased, consistent with a sequential process of anthocyanin degradation. Analysis of gene expression showed down-regulation of flavonol and anthocyanin biosynthesis and of transport-related genes within 24 h of HTLL treatment. No catabolic genes up-regulated by HTLL were found. * Reductions in the concentrations of anthocyanins and down-regulation of the genes of anthocyanin biosynthesis were achieved by environmental manipulation, despite ongoing over-expression of PAP1. Quantitative PCR showed reduced expression of three genes (TT8, TTG1 and EGL3) of the PAP1 transcriptional complex, and increased expression of the potential transcriptional repressors AtMYB3, AtMYB6 and AtMYBL2 coincided with HTLL-induced down-regulation of anthocyanin biosynthesis. * HTLL treatment offers a model system with which to explore anthocyanin catabolism and to discover novel genes involved in the environmental control of anthocyanins.
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Affiliation(s)
- Daryl D Rowan
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11 030, Palmerston North, New Zealand
| | - Mingshu Cao
- AgResearch Grasslands, AgResearch Limited, Private Bag 11008, Palmerston North, New Zealand
| | - Kui Lin-Wang
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92 169, Auckland, New Zealand
| | - Janine M Cooney
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 3123, Hamilton, New Zealand
| | - Dwayne J Jensen
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 3123, Hamilton, New Zealand
| | - Paul T Austin
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11 030, Palmerston North, New Zealand
| | - Martin B Hunt
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11 030, Palmerston North, New Zealand
| | - Cara Norling
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11 030, Palmerston North, New Zealand
| | - Roger P Hellens
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92 169, Auckland, New Zealand
| | - Robert J Schaffer
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92 169, Auckland, New Zealand
| | - Andrew C Allan
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92 169, Auckland, New Zealand
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10
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Deng D, Lauren DR, Cooney JM, Jensen DJ, Wurms KV, Upritchard JE, Cannon RD, Wang MZ, Li MZ. Antifungal saponins from Paris polyphylla Smith. Planta Med 2008; 74:1397-402. [PMID: 18729041 DOI: 10.1055/s-2008-1081345] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Three steroidal saponins, including one new and two known compounds, were isolated from the rhizomes of Paris polyphylla Smith. One- and two-dimensional NMR, LC-MS, and interpretation of hydrolytic cleavage experiments led to the identification of the structure of the new saponin as ( 25R)-spirost-5-ene-3 beta,17 alpha-diol (pennogenin) 3- O-{ O- alpha- L-rhamnopyranosyl-(1-->2)- O-[ O- beta-xylopyranosyl-(1-->5)- alpha- L-arabinofuranosyl-(1-->4)]- beta- D-glucopyranoside}. The isolated saponins were evaluated for their antifungal activity against Cladosporium cladosporioides and Candida species and showed comparable activity to chemicals used in some commercial products.
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Affiliation(s)
- Dawei Deng
- HortResearch, Ruakura Research Centre, Hamilton, New Zealand.
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11
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Stevenson DE, Hansen RP, Loader JI, Jensen DJ, Cooney JM, Wilkins AL, Miles CO. Preparative enzymatic synthesis of glucuronides of zearalenone and five of its metabolites. J Agric Food Chem 2008; 56:4032-4038. [PMID: 18476699 DOI: 10.1021/jf800379z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The resorcylic acid lactones zearalenone ( 1), alpha-zearalenol ( 2), beta-zearalenol ( 3), alpha-zearalanol (zeranol) ( 4), beta-zearalanol (taleranol) ( 5), and zearalanone ( 6) were converted to their glucuronides on a preparative scale in good yields. Reactions were conducted with bovine uridine 5'-diphosphoglucuronyl transferase (UDPGT) as catalyst and uridine 5'-diphosphoglucuronic acid (UDPGA) as cofactor. The glucuronides were isolated by column chromatography and characterized by NMR spectroscopy and mass spectrometry. Although the principal products were 4- O-glucuronides (i.e., linkage through a phenolic hydroxyl), significant quantities of the 6'- O-glucuronides (i.e., linkage through the aliphatic hydroxyl) of alcohols 2, 4, and 5 were also isolated. In the case of 3, the 2- O-glucuronide was isolated as the minor product. Overall isolated yields of glucuronides, performed on a 20-50 mg scale, were typically ca. 80% based on the resorcylic acid lactone starting material. LC-UV-MS (2) analysis of purified specimens revealed MS (2) fragmentations useful for defining the point of attachment of the glucuronide moiety to the zearalenone nucleus.
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Affiliation(s)
- David E Stevenson
- HortResearch Ltd., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand
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12
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Selwood AI, Ginkel RV, Wilkins AL, Munday R, Ramsdell JS, Jensen DJ, Cooney JM, Miles CO. Semisynthesis of S-desoxybrevetoxin-B2 and brevetoxin-B2, and assessment of their acute toxicities. Chem Res Toxicol 2008; 21:944-50. [PMID: 18335998 DOI: 10.1021/tx700441w] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Brevetoxins are neurotoxins associated with blooms of marine algae such as Karenia brevis and can accumulate in the marine food chain, causing intoxication of marine animals and people consuming seafood. Brevetoxin-B2 ( 5) is a toxic metabolite produced in shellfish exposed to algae that contain brevetoxin-B ( 1). S-Desoxybrevetoxin-B2 ( 4) has been proposed as a cometabolite produced during this transformation, and while LC-MS analyses suggest its presence in shellfish, it has not yet been isolated and characterized. Studies on these materials are severely constrained by the difficulty of obtaining and purifying them from natural sources. We have developed a convenient one-pot conversion of commercially available brevetoxin-B ( 1) into S-desoxybrevetoxin-B2 ( 4), and a simple method for converting 4 into brevetoxin-B2 ( 5). Full NMR and mass-spectral characterization of 4 and 5 confirmed their structures and showed that the ratio of diastereoisomers in the synthetic 4 and 5 was similar to that observed in naturally contaminated shellfish. The LD 50 values for 4, 5, and dihydrobrevetoxin-B ( 6) by ip injection in mice were 211, 400, and 250 microg/kg, respectively. The methodology for synthesis of brevetoxin metabolites should greatly facilitate toxicological, biochemical and immunochemical studies of these substances, as well as the production of analytical standards.
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13
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Stevenson DE, Cooney JM, Jensen DJ, Wibisono R, Adaim A, Skinner MA, Zhang J. Comparison of enzymically glucuronidated flavonoids with flavonoid aglycones in an in vitro cellular model of oxidative stress protection. In Vitro Cell Dev Biol Anim 2008; 44:73-80. [PMID: 18219540 DOI: 10.1007/s11626-007-9072-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 11/15/2007] [Indexed: 11/28/2022]
Abstract
This study modeled, in vitro, the potential effect of conjugative (phase II) metabolism on the cytoprotective capacity of fruit flavonoids against oxidative stress. Flavonoid aglycones were compared with their corresponding isomeric mixtures of glucuronides for their ability to enhance the survival of cultured human Jurkat T and neuroblastoma cells stressed with hydrogen peroxide. Various polyphenolic compounds were tested as substrates in vitro for an ovine liver glucuronyl transferase preparation. Flavonoids and their glycoside derivatives were found to be good substrates, whereas phenolic acids were either poor or nonsubstrates. Five common flavonoids were glucuronidated to prepare mixtures for bioassay testing. Glucuronidation generally weakened the cytoprotective capacities of flavonoids (in the presence of H(2)O(2)), but some compounds were weakened much more than others. The concentration that halved cell death was well below 0.5 microM for most flavonoids tested, but glucuronidation increased median effective concentration values to a range of 1-16 microM. This compares with the generally accepted physiological range (0.1-10 microM) for circulating dietary polyphenolics detected in the body. Therefore, some flavonoids may retain a reduced cytoprotective capacity in vitro, after glucuronidation, whereas others may be effectively inactivated.
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Affiliation(s)
- David E Stevenson
- The Horticulture and Food Research Institute of New Zealand, Private Bag 3123, Waikato Mail Centre, Hamilton 3240, New Zealand.
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Loader JI, Hawkes AD, Beuzenberg V, Jensen DJ, Cooney JM, Wilkins AL, Fitzgerald JM, Briggs LR, Miles CO. Convenient large-scale purification of yessotoxin from Protoceratium reticulatum culture and isolation of a novel furanoyessotoxin. J Agric Food Chem 2007; 55:11093-11100. [PMID: 18052242 DOI: 10.1021/jf072704z] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Yessotoxins from a large-scale culture (226 L) of Protoceratium reticulatum strain CAWD129 were harvested by filtration followed by solid-phase extraction. The extract was purified by column chromatography over basic alumina and reverse-phase flash chromatography to afford pure yessotoxin (193 mg). Isolation of yessotoxin was greatly facilitated by selection of a strain which did not produce analogues that interfered with yessotoxin isolation. In addition to yessotoxin, numerous minor yessotoxins were detected by LC-MS in other fractions. From one of these, an early eluting minor analogue with the same molecular weight as yessotoxin and a similar mass spectrometric fragmentation pattern was isolated. This analogue was identified by NMR and mass spectrometry as a novel yessotoxin analogue containing a furan ring in the side chain. This finding reveals biosynthetic flexibility of the yessotoxin pathway in P. reticulatum and confirms earlier findings of production of many minor yessotoxin analogues by this alga. Production of these analogues appeared to be a constitutive trait of P. reticulatum CAWD129.
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Affiliation(s)
- Jared I Loader
- AgResearch Ltd., Ruakura Research Centre, Hamilton, New Zealand
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15
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Stevenson DE, Cooney JM, Jensen DJ, Zhang J, Wibisono R. Comparison of the relative recovery of polyphenolics in two fruit extracts from a model of degradation during digestion and metabolism. Mol Nutr Food Res 2007; 51:939-45. [PMID: 17628878 DOI: 10.1002/mnfr.200700087] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
To simulate the effects of digestion and metabolism on the survival of different polyphenolic compounds, extracts of blueberry and apple were deglycosylated by acid hydrolysis, followed by enzymic glucuronidation under neutral conditions, yielding approximately 5% overall recovery of polyphenolics. The major polyphenolics before and after the treatment were compared, to estimate which species are likely to be present in the intestinal lumen, undegraded and available for absorption, after consumption of the fruit. Whereas blueberry extract consisted predominantly of anthocyanins, epicatechin and caffeoyl quinate esters, the major components of the treated extract were quercetin glucuronides and (unglucuronidated) caffeoyl quinates, with only traces of anthocyanidin derivatives. In apple extract, compositional changes were less marked, but caffeoyl quinates, procyanidins and quercetin were enriched at the expense of caffeic acid, epicatechin and catechin. Hydrophobic compounds like phloretin and quercetin were extensively glucuronidated, whereas caffeic acid and caffeoyl quinate were not. These results suggest that the major polyphenolic components of a fruit are not necessarily the most important contributors to any health benefits because the polyphenolic composition in the intestinal lumen and consequently, in the circulation, may be considerably different.
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Affiliation(s)
- David E Stevenson
- The Horticulture and Food Research Institute of New Zealand, Hamilton, New Zealand.
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16
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Stevenson DE, Parkar SG, Zhang J, Stanley RA, Jensen DJ, Cooney JM. Combinatorial enzymic synthesis for functional testing of phenolic acid esters catalysed by Candida antarctica lipase B (Novozym 435®). Enzyme Microb Technol 2007. [DOI: 10.1016/j.enzmictec.2006.08.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Wu CSJ, Greenwood DR, Cooney JM, Jensen DJ, Tatnell MA, Cooper GJS, Mountjoy KG. Peripherally administered desacetyl alpha-MSH and alpha-MSH both influence postnatal rat growth and associated rat hypothalamic protein expression. Am J Physiol Endocrinol Metab 2006; 291:E1372-80. [PMID: 16868223 DOI: 10.1152/ajpendo.00480.2005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Desacetyl alpha-MSH predominates over alpha-MSH during development, but whether it is biologically active and has a physiological role is unclear. We compared the effects of 0.3 microg.g(-1).day(-1) desacetyl alpha-MSH with that of 0.3 microg.g(-1).day(-1) alpha-MSH on postnatal body growth by administering the peptides subcutaneously daily for postnatal days 0-14 and also used a two-dimensional gel electrophoresis gel-based proteomic approach to analyze protein changes in hypothalami, the relay center for body weight and growth regulation, after 14 days of treatment. We found that the growth rate between days 1 and 10 was significantly decreased by desacetyl alpha-MSH but not by alpha-MSH, but by day 14, a time reported for development of a mature pattern of hypothalamic innervation, both peptides had significantly increased neonatal growth compared with PBS-treated control rats. Desacetyl alpha-MSH significantly increased spleen weight, but alpha-MSH had no effect. alpha-MSH significantly decreased kidney weight, but desacetyl alpha-MSH had no effect. Both desacetyl alpha-MSH and alpha-MSH significantly decreased brain weight. By 14 days, both peptides significantly changed expression of a number of hypothalamic proteins, specifically metabolic enzymes, cytoskeleton, signaling, and stress response proteins. We show that peripherally administered desacetyl alpha-MSH is biologically active and induces responses that can differ from those for alpha-MSH. In conclusion, desacetyl alpha-MSH appears to be an important regulator of neonatal rat growth.
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Affiliation(s)
- Chia-Shan Jenny Wu
- Department of Physiology, University of Auckland, Auckland 1023, New Zealand
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18
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Stevenson DE, Wibisono R, Jensen DJ, Stanley RA, Cooney JM. Direct acylation of flavonoid glycosides with phenolic acids catalysed by Candida antarctica lipase B (Novozym 435®). Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2006.03.006] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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19
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Deng D, Zhang J, Cooney JM, Skinner MA, Adaim A, Jensen DJ, Stevenson DE. Methylated polyphenols are poor “chemical” antioxidants but can still effectively protect cells from hydrogen peroxide-induced cytotoxicity. FEBS Lett 2006; 580:5247-50. [PMID: 16962587 DOI: 10.1016/j.febslet.2006.08.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Revised: 08/11/2006] [Accepted: 08/24/2006] [Indexed: 11/20/2022]
Abstract
Several polyphenolic compounds, including flavonoids and phenolic acids, were compared with their per-methylated forms in both chemical and cell-based assays for antioxidant capacity. Methylation largely eliminated "chemical" antioxidant capacity, according to ferric reducing antioxidant power and oxygen radical absorbance capacity assays. Methylation, however, only moderately reduced protection of human Jurkat cells in culture, from hydrogen peroxide-mediated cytotoxicity, at physiologically relevant concentrations. Neither methylated nor un-methylated compounds were detectably metabolized by the cells. It appears that the protective mechanism of polyphenolic antioxidants against high concentrations of hydrogen peroxide in human cells may be largely unrelated to chemical antioxidant capacity.
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Affiliation(s)
- Dawei Deng
- HortResearch, The Horticulture and Food Research Institute of New Zealand, Private Bag 92-169, Mt Albert, Auckland, New Zealand
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20
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Miles CO, Wilkins AL, Hawkes AD, Jensen DJ, Cooney JM, Larsen K, Petersen D, Rise F, Beuzenberg V, Lincoln Mackenzie A. Isolation and identification of a cis-C8-diol-ester of okadaic acid from Dinophysis acuta in New Zealand. Toxicon 2006; 48:195-203. [PMID: 16784765 DOI: 10.1016/j.toxicon.2006.04.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2006] [Revised: 04/28/2006] [Accepted: 04/28/2006] [Indexed: 11/25/2022]
Abstract
A cis-isomer of a C(8)-diol ester of okadaic acid (1) was isolated during large-scale purification of pectenotoxins (PTXs) from extracts of Dinophysis acuta collected from the west coast of South Island, New Zealand. The compound was identified by NMR spectroscopic and liquid chromatography-mass spectrometry (LC-MS) studies, and is the first reported cis-isomer of an okadaic acid C(8)-diol-ester identified in Dinophysis. The more abundant trans-C(8)-diol ester of okadaic acid (2) isolated from the same Dinophysis extract was rapidly hydrolyzed to okadaic acid in vitro by the supernatant from green-lipped mussel hepatopancreas.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
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21
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Miles CO, Wilkins AL, Hawkes AD, Jensen DJ, Selwood AI, Beuzenberg V, Mackenzie AL, Cooney JM, Holland PT. Isolation and identification of pectenotoxins-13 and -14 from Dinophysis acuta in New Zealand. Toxicon 2006; 48:152-9. [PMID: 16828828 DOI: 10.1016/j.toxicon.2006.04.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Accepted: 04/10/2006] [Indexed: 11/20/2022]
Abstract
Two novel pectenotoxins (PTXs), PTX-13 and -14, were isolated from extracts of Dinophysis acuta collected from the west coast of South Island, New Zealand. The compounds were identified as oxidized analogues of PTX-2 by NMR spectroscopic and LC-MS studies. PTX-13 (32R-hydroxyPTX-2) corresponds to the unidentified analogue PTX-11x reported by [Suzuki et al., 2003. Liquid chromatography-mass spectrometry of spiroketal stereoisomers of pectenotoxins and the analysis of novel pectenotoxin isomers in the toxic dinoflagellate Dinophysis acuta from New Zealand. J. Chromatogr. A 992, 141-150]. PTX-13 underwent slow deuteration at the 13beta-position during NMR analysis. PTX-14 corresponds to the 32,36-dehydration product of PTX-13, and may be an artifact.
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22
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Suzuki T, Walter JA, LeBlanc P, MacKinnon S, Miles CO, Wilkins AL, Munday R, Beuzenberg V, MacKenzie AL, Jensen DJ, Cooney JM, Quilliam MA. Identification of pectenotoxin-11 as 34S-hydroxypectenotoxin-2, a new pectenotoxin analogue in the toxic dinoflagellate Dinophysis acuta from New Zealand. Chem Res Toxicol 2006; 19:310-8. [PMID: 16485908 DOI: 10.1021/tx050240y] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [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: 11/29/2022]
Abstract
A new pectenotoxin, which has been named pectenotoxin-11 (PTX11), was isolated from the dinoflagellate Dinophysis acuta collected from the west coast of New Zealand. The structure of PTX11 was determined as 34S-hydroxypectenotoxin-2 by tandem mass spectrometry and UV and NMR spectroscopy. PTX11 appears to be only the third pectenotoxin identified as a natural biosynthetic product from algae after pectenotoxin-2 and pectenotoxin-12. The LD50 of PTX11 determined by mouse intraperitoneal injection was 244 microg/kg. The LD(min) of PTX11 in these experiments was 250 microg/kg. No signs of toxicity were recorded in mice following an oral dose of PTX11 at 5000 microg/kg. No diarrhea was observed in any of the animals administered with the test substance by either route of administration. Unlike pectenotoxin-2 (PTX2), PTX11 was not readily hydrolyzed to its corresponding seco acid by enzymes from homogenized green-lipped mussel (Perna canaliculus) hepatopancreas.
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Affiliation(s)
- Toshiyuki Suzuki
- Institute for Marine Biosciences, National Research Council, 1411 Oxford Street, Halifax, NS B3H 3Z1, Canada
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23
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Miles CO, Wilkins AL, Selwood AI, Hawkes AD, Jensen DJ, Cooney JM, Beuzenberg V, MacKenzie AL. Isolation of Yessotoxin 32-O-[β-l-arabinofuranosyl-(5′→1″)-β-l-arabinofuranoside] from Protoceratium reticulatum. Toxicon 2006; 47:510-6. [PMID: 16530240 DOI: 10.1016/j.toxicon.2005.12.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 12/20/2005] [Accepted: 12/21/2005] [Indexed: 11/30/2022]
Abstract
Yessotoxin 32-O-[beta-L-arabinofuranosyl-(5'-->1'')-beta-L-arabinofuranoside] (3) was isolated from extracts of Protoceratium reticulatum during a large scale isolation of yessotoxin (1). The structure was characterized by mass spectrometry and NMR spectroscopy. Di-glycoside-3, along with the corresponding mono-glycoside (2) were detected in cultures of P. reticulatum originating from Europe and New Zealand, suggesting that production of arabinosides of 1 is a normal feature of this alga. Formation of multiply charged anions and fragmentation of 3 occurred much more readily than for 1 and 2 under the LC-MS conditions used in this study.
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Affiliation(s)
- Christopher O Miles
- Department of Toxinology, AgResearch Ltd, Ruakura Research Centre, PB 3123, East Street, Hamilton, New Zealand.
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24
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Miles CO, Wilkins AL, Munday JS, Munday R, Hawkes AD, Jensen DJ, Cooney JM, Beuzenberg V. Production of 7-epi-pectenotoxin-2 seco acid and assessment of its acute toxicity to mice. J Agric Food Chem 2006; 54:1530-4. [PMID: 16478284 DOI: 10.1021/jf0523871] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Pectenotoxins (PTXs) accumulate in shellfish feeding on dinoflagellates of the genus Dinophysis, so that humans can be exposed to these toxins through shellfish consumption. Some PTXs are toxic to experimental animals, whereas others are of much lower toxicity. Pectenotoxin-2, the most abundant PTX from most Dinophysis spp., is rapidly metabolized by most shellfish to a mixture of pectenotoxin-2 seco acid (2) and 7-epi-pectenotoxin-2 seco acid (1). A mixture of 1 and 2 was produced during purification of an extract from in vitro enzymatic hydrolysis of pectenotoxin-2. These were separated by preparative HPLC, and the structure of 1 was confirmed by one- and two-dimensional 1H and 13C NMR spectroscopy and LC-MS3 analyses. No toxic changes were recorded in mice injected intraperitoneally with 1 or 2 at a dose of 5000 microg/kg. PTX seco acids are therefore unlikely to be of consequence to human consumers at the concentrations found in contaminated shellfish.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
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25
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Miles CO, Wilkins AL, Hawkes AD, Selwood AI, Jensen DJ, Cooney JM, Beuzenberg V, MacKenzie AL. Identification of 45-hydroxy-46,47-dinoryessotoxin, 44-oxo-45,46,47-trinoryessotoxin, and 9-methyl-42,43,44,45,46,47,55-heptanor-38-en-41-oxoyessotoxin, and partial characterization of some minor yessotoxins, from Protoceratium reticulatum. Toxicon 2006; 47:229-40. [PMID: 16375937 DOI: 10.1016/j.toxicon.2005.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Revised: 11/01/2005] [Accepted: 11/02/2005] [Indexed: 11/25/2022]
Abstract
Preparative HPLC purification of a side-fraction obtained during purification of 44,55-dihydroxyyessotoxin (6) afforded fractions containing previously unidentified yessotoxin analogues. Careful analysis of these fractions by HPLC-UV, LC-MS3, and NMR spectroscopy, revealed the identities of some of these analogues as 45-hydroxy-46,47-dinoryessotoxin (1), 44-oxo-45,46,47-trinoryessotoxin (2) and 9-methyl-42,43,44,45,46,47,55-heptanor-38-en-41-oxoyessotoxin (5). Numerous other analogues were present but could only be characterized by HPLC-UV and LC-MS3 due to their low abundance. The HPLC-UV and LC-MS3 data confirm the presence of large numbers of yessotoxin analogues, some of which may be oxidative degradation products, in extracts of Protoceratium reticulatum. Compound-1 is the first 46,47-dinoryessotoxin to be identified.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd, Department of Toxinology, Ruakura Research Centre, Private Bag 3123, East Street, Hamilton, New Zealand.
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26
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Finch SC, Wilkins AL, Hawkes AD, Jensen DJ, MacKenzie AL, Beuzenberg V, Quilliam MA, Olseng CD, Samdal IA, Aasen J, Selwood AI, Cooney JM, Sandvik M, Miles CO. Isolation and identification of (44-R,S)-44,55-dihydroxyyessotoxin from Protoceratium reticulatum, and its occurrence in extracts of shellfish from New Zealand, Norway and Canada. Toxicon 2005; 46:160-70. [PMID: 15975615 DOI: 10.1016/j.toxicon.2005.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Revised: 03/08/2005] [Accepted: 03/08/2005] [Indexed: 10/25/2022]
Abstract
44,55-Dihydroxyyessotoxin (1) was isolated from extracts of Protoceratium reticulatum and identified by analysis of its one- and two-dimensional NMR and mass spectra. In addition, LC-MS methods revealed the presence of compounds tentatively identified as (44-R,S)-44,55-dihydroxy-41a-homoyessotoxin (2) and (44-R,S)-44,55-dihydroxy-9-methyl-41a-homoyessotoxin (3). LC-MS analyses indicate that 1 is a constituent of P. reticulatum in New Zealand and Norway, and it was present in three species of mussels from New Zealand, Norway, and Canada.
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Affiliation(s)
- Sarah C Finch
- AgResearch Ltd, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand
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27
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Miles CO, Wilkins AL, Samdal IA, Sandvik M, Petersen D, Quilliam MA, Naustvoll LJ, Rundberget T, Torgersen T, Hovgaard P, Jensen DJ, Cooney JM. A novel pectenotoxin, PTX-12, in Dinophysis spp. and shellfish from Norway. Chem Res Toxicol 2005; 17:1423-33. [PMID: 15540940 DOI: 10.1021/tx049870a] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two novel pectenotoxins (PTXs) were detected by LC-MS in solid phase extracts of net hauls taken at Flødevigen, Norway, in June 2002 that were dominated by Dinophysis acuminata and Dinophysis norvegica. The new compounds were isolated as minor components from a large collection of a Dinophysis acuta-dominated bloom obtained from Skjer, Sognefjorden, Norway, in October 2002. LC-MS and NMR analyses revealed that the new components, 36S-PTX-12 and 36R-PTX-12, occurred as a pair of equilibrating diastereoisomers differing from PTX-2 in that they contained an exocylic olefinic methylene rather than a methyl group at C-38. Analyses of shellfish extracts revealed that PTX-12 accumulated in Norwegian blue mussels (Mytilus edulis) and cockles (Cerastoderma edule), along with PTX-12 seco acids occurring as a complex mixture of diastereoisomers. LC-MS analysis of algal cells picked from the net haul from Flødevigen revealed that PTX-12 predominated in D. acuta and D. norvegica, whereas PTX-2 was the predominant pectenotoxin in D. acuminata. Preliminary observations indicate that the relative contents of PTX-2 and PTX-12 vary between sites and years in Norway, even within a single species of Dinophysis. Our data also suggest that heterotrophic dinoflagellates may accumulate toxins from their prey.
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Miles CO, Wilkins AL, Hawkes AD, Selwood AI, Jensen DJ, Munday R, Cooney JM, Beuzenberg V. Polyhydroxylated amide analogs of yessotoxin from Protoceratium reticulatum. Toxicon 2005; 45:61-71. [PMID: 15581684 DOI: 10.1016/j.toxicon.2004.09.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Revised: 09/20/2004] [Accepted: 09/21/2004] [Indexed: 11/24/2022]
Abstract
Two analogs of yessotoxin were isolated from extracts of a culture of Protoceratium reticulatum. The structures of the analogs were identified as trihydroxylated amides of 41a-homoyessotoxin (1) and 9-methyl-41a-homoyessotoxin (2) by one- and two-dimensional 1H and 13C NMR spectroscopy and LC-MS3 analyses. Structures were further confirmed by micro-scale chemical conversions combined with LC-MS3 analyses. No toxic effects were recorded in mice injected intraperitoneally with 2 at a dose of 5000 microg/kg.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
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Miles CO, Wilkins AL, Jensen DJ, Cooney JM, Quilliam MA, Aasen J, MacKenzie AL. Isolation of 41a-Homoyessotoxin and the Identification of 9-Methyl-41a-homoyessotoxin and Nor-ring A-yessotoxin from Protoceratium reticulatum. Chem Res Toxicol 2004; 17:1414-22. [PMID: 15540939 DOI: 10.1021/tx049832r] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
41a-homoyessotoxin (1), a new analogue of yessotoxin (7), was isolated from extracts of Protoceratium reticulatum grown in culture. In addition, 9-methyl-41a-homoyessotoxin (2) and a nor-ring A-yessotoxin (3) were identified as the major components of a mixed fraction. The structural information was initially obtained from LC-UV and LC-MS3 chromatograms, with subsequent definitive structure determination by NMR, LC-MS/MS, and high-resolution MS. Full 1H and indirectly detected 13C NMR assignments for all but two carbon atoms were obtained from ca. 100 microg of 1. Full 1H NMR assignments for 2 and 3 and identification of three new heptanor-41-oxo-analogues of 3 (4-6) during LC-MS3 analysis of a fraction containing 1-3 and 7 are also reported.
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Miles CO, Wilkins AL, Hawkes AD, Selwood A, Jensen DJ, Aasen J, Munday R, Samdal IA, Briggs LR, Beuzenberg V, MacKenzie AL. Isolation of a 1,3-enone isomer of heptanor-41-oxoyessotoxin from Protoceratium reticulatum cultures. Toxicon 2004; 44:325-36. [PMID: 15321705 DOI: 10.1016/j.toxicon.2004.06.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Revised: 06/11/2004] [Accepted: 06/12/2004] [Indexed: 11/24/2022]
Abstract
The 1,3-enone isomer (1) of heptanor-41-oxoyessotoxin (2) was isolated from extracts of Protoceratium reticulatum during large-scale production of yessotoxin (4). We found that 2 readily isomerizes to 1 in the presence of dilute ammonia and present evidence for the existence of 40-epi-2 (3) that also isomerizes to 1. 1-3 were detected by LC-MS methods both in extracts of P. reticulatum cultures and in mussels contaminated with yessotoxins. The isomerization of 2 and 3 into 1 occurs so readily that purification on basic alumina needs to be conducted carefully. No toxic effects were recorded in mice injected intraperitoneally with 1 at a dose of 5,000 microg/kg.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd, Ruakura Research Centre, Department of Toxinology, Private Bag 3123, Hamilton, New Zealand.
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31
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Miles CO, Wilkins AL, Munday R, Dines MH, Hawkes AD, Briggs LR, Sandvik M, Jensen DJ, Cooney JM, Holland PT, Quilliam MA, MacKenzie AL, Beuzenberg V, Towers NR. Isolation of pectenotoxin-2 from Dinophysis acuta and its conversion to pectenotoxin-2 seco acid, and preliminary assessment of their acute toxicities. Toxicon 2004; 43:1-9. [PMID: 15037023 DOI: 10.1016/j.toxicon.2003.10.003] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2003] [Revised: 09/15/2003] [Accepted: 10/06/2003] [Indexed: 11/23/2022]
Abstract
We have developed a simple and effective method for isolating pectenotoxin-2 (PTX-2) from Dinophysis cells collected from a natural bloom. A two-step extraction procedure followed by two column chromatography steps produced PTX-2 in high purity suitable for use as an analytical standard and for toxicological studies. Incubation of purified PTX-2 with the supernatant from ultracentrifuged blue (Mytilus edulis) or Greenshell (Perna canaliculus) mussel hepatopancreas homogenate caused rapid conversion to pectenotoxin-2 seco acid (PTX-2 SA). Purification of PTX-2 SA was achieved by solvent extraction followed by column chromatography. PTX-2 and PTX-2 SA were fully characterized by LC-MS and NMR, and full (1)H and (13)C NMR assignments were obtained. Okadaic acid C(8)-diol ester was isolated during the purification of PTX-2, and its identity confirmed by NMR and LC-MS analyses. Pectenotoxin-2 seco acid methyl ester, identified by LC-MS, was also produced during the hydrolytic procedure due to the presence of methanol. PTX-2 was acutely toxic to mice by i.p. injection (LD(50)=219 microg/kg) but no effects were seen with PTX-2 SA at 5000 microg/kg. Neither PTX-2 nor PTX-2 SA was overtly toxic to mice by the oral route at doses up to 5000 microg/kg. No diarrhea was observed in mice dosed with either compound, suggesting that pectenotoxins do not belong in the diarrhetic shellfish poison group.
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Affiliation(s)
- Christopher O Miles
- AgResearch Ltd., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
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McGhie TK, Ainge GD, Barnett LE, Cooney JM, Jensen DJ. Anthocyanin glycosides from berry fruit are absorbed and excreted unmetabolized by both humans and rats. J Agric Food Chem 2003; 51:4539-48. [PMID: 14705874 DOI: 10.1021/jf026206w] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Anthocyanins, the red/blue pigments found in plants, are polyphenolic compounds consumed by humans and are part of a normal diet. Recent studies have shown that anthocyanins have substantial bioactivity including antioxidant activity and therefore may have beneficial effects on human health. Anthocyanins are a group of over 500 compounds of diverse structures containing different core phenolic aglycons and conjugated with sugars in a variety of glycosylation patterns. In this study, we have investigated the bioabsorption of 15 anthocyanins with structures containing different aglycons and conjugated sugars extracted from blueberry, boysenberry, black raspberry, and blackcurrant in both humans and rats. Intact and unmetabolized anthocyanins were detected in urine of rats and humans following dosing for all molecular structures investigated, thus demonstrating that anthocyanins with diverse molecular structure and from different dietary sources are bioavailable at diet relevant dosage rates. In addition, the relative concentrations of anthocyanins detected in urine following dosing varied, indicating that differences in bioavailability are due to variations in chemical structure. Our results suggest that the nature of the sugar conjugate and the phenolic aglycon are both important determinants of anthocyanin absorption and excretion in rats and humans.
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Affiliation(s)
- Tony K McGhie
- The Horticulture and Food Research Institute of New Zealand Ltd, Private Bag 11 030, Palmerston North, New Zealand
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Lauren DR, Jensen DJ, Douglas JA, Follett JM. Efficient method for determining the glycyrrhizin content of fresh and dried roots, and root extracts, of Glycyrrhiza species. Phytochem Anal 2001; 12:332-335. [PMID: 11705261 DOI: 10.1002/pca.597] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A reliable and efficient method suitable for the selective analysis of the glycyrrhizin content of fresh and dried roots of Glycyrrhiza species and of root extracts is described. The method was optimised for recovery and analysis of glycyrrhizin after conversion to its aglycone, 18 beta-glycyrrhetinic acid. The reversed-phase HPLC system was developed using a sterically protected C8 column that allowed UV detection of the aglycone at 254 mm without interference from co-occurring components. The average recovery through the method was determined at 83%, with a range of 65-99%. Analysis of 150 dried root samples gave levels of glycyrrhizin consistent with earlier reported values. A comparison of post-harvest treatment conditions. showed that the drying of root samples at up to 65 degrees C did not result in any measurable reduction in glycyrrhizin.
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Affiliation(s)
- D R Lauren
- Horticulture and Food Research Institute of New Zealand, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
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Stokes WS, Jensen DJ. Guidelines for Institutional Animal Care and Use Committees: consideration of alternatives. Contemp Top Lab Anim Sci 1995; 34:51-5, 58-60. [PMID: 16457554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Affiliation(s)
- W S Stokes
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
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Sertl GO, Jensen DJ. Comments on biocompatible osteoconductive polymer. J Am Vet Med Assoc 1992; 201:1489-90. [PMID: 1289316] [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: 12/26/2022]
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Abstract
The BOP/Sertl shelf arthroplasty procedure is not difficult or lengthy. It uses minimal metallic fixation. It is quite physiological with minimal morbidity because there is no change in the bony anatomic pelvis except to create an extension of the lateral rim of the acetabulum. The animal is able to walk the day after surgery. The procedure can be performed bilaterally the same day, thus creating good bony stability and decreasing stretching of the joint capsule, which in turn prevents further subluxation and pain in the hip joint. The aim of this procedure is to return the animal to a satisfactory lifestyle through an effective but less complicated surgical procedure as compared to other available options. This procedure is straightforward and can be done by a surgeon who is familiar with orthopedic surgical techniques and has been trained in this procedure. To date, more than 150 veterinarians have had hands-on training to perform this operation. We are not claiming that this procedure is a cure for CHD; rather, it is a procedure that dramatically slows down the progress of this malady and allows the dog to lead a more normal lifestyle and avoids euthanasia. After 51 months, our study of 200 hips has had a success rate of 99% on the animals available for follow-up as evidenced by returning those animals to a satisfactory lifestyle with stable hips.
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Affiliation(s)
- D J Jensen
- Page Animal Hospital, St. Louis, Missouri
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Jensen DJ. The applicability of nursing diagnoses in the neonatal intensive care unit. Neonatal Netw 1990; 9:23-9. [PMID: 2392113] [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: 12/31/2022]
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Jensen DJ, Brey WW, Delayre JL, Narayana PA. Reduction of pulsed gradient settling time in the superconducting magnet of a magnetic resonance instrument. Med Phys 1987; 14:859-62. [PMID: 3683316 DOI: 10.1118/1.596012] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The implementation of electronic compensation for eddy currents to reduce the gradient settling times on a superconducting magnet is described. Field plots inside the magnet indicate the importance of assessing the field changes at several positions in the magnet. The effect of an asymmetry between the gradient coil system and the cryostat is demonstrated. A modified compensation circuit is described to overcome this mechanical asymmetry.
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Affiliation(s)
- D J Jensen
- Department of Radiology, University of Texas Medical School, Houston 77030
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Abstract
Mumps virus-infected and normal newborn hamster brains were imaged with magnetic resonance (MR) within 24 h after birth and serially scanned. Hydrocephalus developed explosively on Day 6 postinfection and progressed until death occurred soon after Day 10. This study demonstrates the utility of MR in the investigation of experimental viral encephalitis in very small laboratory animals.
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Jensen DJ, Delayre JL, Narayana PA. An incremental phase shifter and frequency modulator for magnetic resonance imaging and spectroscopy. IEEE Trans Biomed Eng 1987; 34:310-3. [PMID: 3504205 DOI: 10.1109/tbme.1987.326047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Abstract
The design of a pulse sequence for volume localization in magnetic resonance spectroscopy is described in detail. The sequence is based on the volume selective excitation technique (VSE) proposed by Aue et al. [J. Magn. Reson. 56, 350 (1984)] and overcomes the high rf power requirements of VSE. The implications of various design stages are demonstrated experimentally and by computer simulations.
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Jensen DJ, Getzendaner ME, Hummel RA, Turley J. Residue studies for (2,4,5-trichlorophenoxy)acetic acid and 2,3,7,8-tetrachlorodibenzo-p-dioxin in grass and rice. J Agric Food Chem 1983; 31:118-122. [PMID: 6826908 DOI: 10.1021/jf00115a029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Jensen DJ, Hummel RA. Secretion of TCDD in milk and cream following the feeding of TCDD to lactating dairy cows. Bull Environ Contam Toxicol 1982; 29:440-446. [PMID: 6890865 DOI: 10.1007/bf01605609] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Jensen DJ, Hummel RA, Mahle NH, Kocher CW, Higgins HS. A residue study on beef cattle consuming 2,3,7,8-tetrachlorodibenzo-p-dioxin. J Agric Food Chem 1981; 29:265-268. [PMID: 7229210 DOI: 10.1021/jf00104a014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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