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Jürgen Rullkötter - One of the best experts on this subject based on the ideXlab platform.
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Cardiac glycosides from Yellow Oleander (Thevetia peruviana) seeds
Phytochemistry, 2011Co-Authors: Sarah Kohls, Barbara M. Scholz-böttcher, Jörg Teske, Patrick Zark, Jürgen RullkötterAbstract:Thevetia cardiac glycosides can lead to intoxication, thus they are important indicators for forensic and pharmacologic surveys. Six Thevetia cardiac glycosides, including two with unknown structures, were isolated from the seeds of the Yellow Oleander (Thevetia peruviana (Pers.) K. Shum., Apocynaceae). LC-ESI⁺-MS(/MS) analysis under high-resolution conditions used as a qualitative survey of the primary glycosides did not lead to fragmentation of the aglycones. Acid hydrolysis of the polar and non-volatile Thevetia glycosides under severe conditions yielded the aglycones of the Thevetia glycosides and made them amenable to GC-MS analysis. Comparison of mass spectral fragmentation patterns of the aglycones, as well as high-resolution mass spectrometric and NMR data of four of the primary Thevetia glycosides including the two unknowns, revealed the structures of the complete set of six Thevetia glycosides. The identified compounds are termed thevetin C and acetylthevetin C and differ by an 18,20-oxido-20,22-dihydro functionality from thevetin B and acetylthevetin B, respectively. The absence of an unsaturated lactone ring renders the glycosides cardio-inactive. The procedures developed in this study and the sets of analytical data obtained will be useful for screening and structure assessment of other, particularly polar, cardiac glycosides.
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Method validation of a survey of Thevetia cardiac glycosides in serum samples.
Forensic science international, 2011Co-Authors: Sarah Kohls, Jürgen Rullkötter, Barbara Scholz-böttcher, Jörg TeskeAbstract:A sensitive and specific liquid chromatography tandem mass spectrometry (HPLC-ESI(+)-MS/MS) procedure was developed and validated for the identification and quantification of thevetin B and further cardiac glycosides in human serum. The seeds of Yellow Oleander (Thevetia peruviana) contain cardiac glycosides that can cause serious intoxication. A mixture of six Thevetia glycosides was extracted from these seeds and characterized. Thevetin B, isolated and efficiently purified from that mixture, is the main component and can be used as evidence. Solid phase extraction (SPE) proved to be an effective sample preparation method. Digoxin-d3 was used as the internal standard. Although ion suppression occurs, the limit of detection (LOD) is 0.27 ng/ml serum for thevetin B. Recovery is higher than 94%, and accuracy and precision were proficient. Method refinement was carried out with regard to developing a general screening method for cardiac glycosides. The assay is linear over the range of 0.5-8 ng/ml serum. Finally, the method was applied to a case of Thevetia seed ingestion.
Sarah Kohls - One of the best experts on this subject based on the ideXlab platform.
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Cardiac glycosides from Yellow Oleander (Thevetia peruviana) seeds
Phytochemistry, 2011Co-Authors: Sarah Kohls, Barbara M. Scholz-böttcher, Jörg Teske, Patrick Zark, Jürgen RullkötterAbstract:Thevetia cardiac glycosides can lead to intoxication, thus they are important indicators for forensic and pharmacologic surveys. Six Thevetia cardiac glycosides, including two with unknown structures, were isolated from the seeds of the Yellow Oleander (Thevetia peruviana (Pers.) K. Shum., Apocynaceae). LC-ESI⁺-MS(/MS) analysis under high-resolution conditions used as a qualitative survey of the primary glycosides did not lead to fragmentation of the aglycones. Acid hydrolysis of the polar and non-volatile Thevetia glycosides under severe conditions yielded the aglycones of the Thevetia glycosides and made them amenable to GC-MS analysis. Comparison of mass spectral fragmentation patterns of the aglycones, as well as high-resolution mass spectrometric and NMR data of four of the primary Thevetia glycosides including the two unknowns, revealed the structures of the complete set of six Thevetia glycosides. The identified compounds are termed thevetin C and acetylthevetin C and differ by an 18,20-oxido-20,22-dihydro functionality from thevetin B and acetylthevetin B, respectively. The absence of an unsaturated lactone ring renders the glycosides cardio-inactive. The procedures developed in this study and the sets of analytical data obtained will be useful for screening and structure assessment of other, particularly polar, cardiac glycosides.
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Method validation of a survey of Thevetia cardiac glycosides in serum samples.
Forensic science international, 2011Co-Authors: Sarah Kohls, Jürgen Rullkötter, Barbara Scholz-böttcher, Jörg TeskeAbstract:A sensitive and specific liquid chromatography tandem mass spectrometry (HPLC-ESI(+)-MS/MS) procedure was developed and validated for the identification and quantification of thevetin B and further cardiac glycosides in human serum. The seeds of Yellow Oleander (Thevetia peruviana) contain cardiac glycosides that can cause serious intoxication. A mixture of six Thevetia glycosides was extracted from these seeds and characterized. Thevetin B, isolated and efficiently purified from that mixture, is the main component and can be used as evidence. Solid phase extraction (SPE) proved to be an effective sample preparation method. Digoxin-d3 was used as the internal standard. Although ion suppression occurs, the limit of detection (LOD) is 0.27 ng/ml serum for thevetin B. Recovery is higher than 94%, and accuracy and precision were proficient. Method refinement was carried out with regard to developing a general screening method for cardiac glycosides. The assay is linear over the range of 0.5-8 ng/ml serum. Finally, the method was applied to a case of Thevetia seed ingestion.
Jörg Teske - One of the best experts on this subject based on the ideXlab platform.
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Cardiac glycosides from Yellow Oleander (Thevetia peruviana) seeds
Phytochemistry, 2011Co-Authors: Sarah Kohls, Barbara M. Scholz-böttcher, Jörg Teske, Patrick Zark, Jürgen RullkötterAbstract:Thevetia cardiac glycosides can lead to intoxication, thus they are important indicators for forensic and pharmacologic surveys. Six Thevetia cardiac glycosides, including two with unknown structures, were isolated from the seeds of the Yellow Oleander (Thevetia peruviana (Pers.) K. Shum., Apocynaceae). LC-ESI⁺-MS(/MS) analysis under high-resolution conditions used as a qualitative survey of the primary glycosides did not lead to fragmentation of the aglycones. Acid hydrolysis of the polar and non-volatile Thevetia glycosides under severe conditions yielded the aglycones of the Thevetia glycosides and made them amenable to GC-MS analysis. Comparison of mass spectral fragmentation patterns of the aglycones, as well as high-resolution mass spectrometric and NMR data of four of the primary Thevetia glycosides including the two unknowns, revealed the structures of the complete set of six Thevetia glycosides. The identified compounds are termed thevetin C and acetylthevetin C and differ by an 18,20-oxido-20,22-dihydro functionality from thevetin B and acetylthevetin B, respectively. The absence of an unsaturated lactone ring renders the glycosides cardio-inactive. The procedures developed in this study and the sets of analytical data obtained will be useful for screening and structure assessment of other, particularly polar, cardiac glycosides.
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Method validation of a survey of Thevetia cardiac glycosides in serum samples.
Forensic science international, 2011Co-Authors: Sarah Kohls, Jürgen Rullkötter, Barbara Scholz-böttcher, Jörg TeskeAbstract:A sensitive and specific liquid chromatography tandem mass spectrometry (HPLC-ESI(+)-MS/MS) procedure was developed and validated for the identification and quantification of thevetin B and further cardiac glycosides in human serum. The seeds of Yellow Oleander (Thevetia peruviana) contain cardiac glycosides that can cause serious intoxication. A mixture of six Thevetia glycosides was extracted from these seeds and characterized. Thevetin B, isolated and efficiently purified from that mixture, is the main component and can be used as evidence. Solid phase extraction (SPE) proved to be an effective sample preparation method. Digoxin-d3 was used as the internal standard. Although ion suppression occurs, the limit of detection (LOD) is 0.27 ng/ml serum for thevetin B. Recovery is higher than 94%, and accuracy and precision were proficient. Method refinement was carried out with regard to developing a general screening method for cardiac glycosides. The assay is linear over the range of 0.5-8 ng/ml serum. Finally, the method was applied to a case of Thevetia seed ingestion.
Michael Eddleston - One of the best experts on this subject based on the ideXlab platform.
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a review of the natural history toxinology diagnosis and clinical management of nerium oleander common oleander and Thevetia peruviana yellow oleander poisoning
Toxicon, 2010Co-Authors: Veronika Bandara, Scott A Weinstein, Julian White, Michael EddlestonAbstract:Nerium oleander (common oleander) and Thevetia peruviana (yellow oleander) are potentially lethal plants after ingestion. Poisoning by these plants is a common toxicological emergency in tropical and subtropical parts of the world and intentional self-harm using T. peruviana is prevalent in South Asian countries, especially India and Sri Lanka. All parts of these plants are toxic, and contain a variety of cardiac glycosides including neriifolin, thevetin A, thevetin B, and oleandrin. Ingestion of either oleander results in nausea, vomiting, abdominal pain, diarrhoea, dysrhythmias, and hyperkalemia. In most cases, clinical management of poisoning by either N. oleander or T. peruviana involves administration of activated charcoal and supportive care. Digoxin specific Fab fragments are an effective treatment of acute intoxication by either species. However, where limited economic resources restrict the use of such Fab fragments, treatment of severely poisoned patients is difficult. Data from case reports and clinical studies were reviewed to identify treatments supported by evidence for the management of poisoning by N. oleander and T. peruviana.
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Pharmacokinetics of Digoxin Cross-Reacting Substances in Patients With Acute Yellow Oleander (Thevetia peruviana) Poisoning, Including the Effect of Activated Charcoal
Therapeutic drug monitoring, 2006Co-Authors: Darren M. Roberts, Michael Eddleston, Emma Southcott, Julia M. Potter, Michael S. Roberts, Nicholas A. BuckleyAbstract:Intentional self-poisonings with seeds from the yellow oleander tree (Thevetia peruviana) are widely reported. Activated charcoal has been suggested to benefit patients with yellow oleander poisoning by reducing absorption and/or facilitating elimination. Two recent randomized controlled trials (RCTs) assessing the efficacy of activated charcoal yielded conflicting outcomes in terms of mortality. The effect of activated charcoal on the pharmacokinetics of Thevetia cardenolides has not been assessed. This information may be useful for determining whether further studies are necessary. Serial blood samples were obtained from patients enrolled in an RCT assessing the relative efficacy of single-dose and multiple-dose activated charcoal (SDAC and MDAC, respectively) compared with no activated charcoal (NoAC). The concentration of Thevetia cardenolides was estimated with a digoxin immunoassay. The effect of activated charcoal on cardenolide pharmacokinetics was compared between treatment groups by determining the area under the curve for each patient in the 24 hours following admission, the 24-hour mean residence time, and regression lines obtained from serial concentration points, adjusted for exposure. Erratic and prolonged absorption patterns were noted in each patient group. The apparent terminal half-life was highly variable, with a median time of 42.9 hours. There was a reduction in 24-hour mean residence time and in the apparent terminal half-life estimated from linear regression in patients administered activated charcoal, versus the control group (NoAC). This effect was approximately equal in patients administered MDAC or SDAC. Activated charcoal appears to favorably influence the pharmacokinetic profile of Thevetia cardenolides in patients with acute self-poisoning and may have clinical benefits. Given the conflicting clinical outcomes noted in previous RCTs, these mechanistic data support the need for further studies to determine whether a particular subgroup of patients (eg, those presenting soon after poisoning) will benefit from activated charcoal.
J. O. Atteh - One of the best experts on this subject based on the ideXlab platform.
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Apparent nitrogen corrected and true metabolisable energy of processed Thevetia oil for broiler finisher birds
Nigerian Journal of Animal Production, 2001Co-Authors: O A Adeyemi, J. O. Atteh, IbiyemiAbstract:Sixty, finishing broilers aged 35 days were used to determine the Apparent, Nitrogen corrected and True metabolisable energy value of Thevetia oil. The oil was subjected to heat treatment of 110°C for 25 minutes. Four experimental diets consisting of a basal diet and three other diets in which Thevetia oil was substituted for 2.5, 5.0 and 10.0% of the basal diet. The experiment lasted for 10 days, made up of a 7-day adjustment period and a 3-day total collection period. Protein and fibre retention were significantly (P
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Determination of the apparent and true metabolisable energy value of Thevetia oil
Nigerian Journal of Animal Production, 2001Co-Authors: O A Adeyemi, J. O. Atteh, IbiyemlAbstract:An experiment was designed to evaluate the metabolisable energy value of solvent extracted Thevetia oil for the chicken. Apart from the metabolisable energy value, the productive performance and nutrient retention was also examined. Day-old broiler chicks were fed diets with 0.0, 2.5, 5.0 or 10.0% Thevetia oil over a 2-week period. There was no significant difference (P
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Response of broilers to dietary levels of Thevetia cake
The Journal of Agricultural Science, 1995Co-Authors: J. O. Atteh, S. A. Ibiyemi, A. O. OjoAbstract:Two experiments done at the University of Ilorin, Nigeria, in 1992/93 investigated the effects of dietary levels of Thevetia cake on the performance and nutrient retention of broilers. In Expt 1, day-old broiler chicks were fed either a control diet or diets containing 5, 10 or 15 % Thevetia cake during a 4-week period. In Expt 2, day-old broiler chicks were fed a standard diet until 4 weeks of age and were then switched to diets containing 0, 5, 10 or 15% Thevetia cake. Inclusion of Thevetia cake in broiler diets, irrespective of level of inclusion, drastically reduced feed intake and weight gain (P < 0.01) at both the starter and finisher stages. Dietary Thevetia cake also caused a significant increase in mortality rate (P < 0.01). There was a reduction in protein and fibre retention and dietary ME with increases in the dietary level of Thevetia cake at both the starter and finisher stages (P < 0.05). It is concluded that Thevetia cake is toxic to broilers and needs further processing before it can effectively be used as an ingredient in broiler feed.
