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334
result(s) for
"Indans - analysis"
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Two New Metabolites from the Endophytic Fungus Alternaria sp. A744 Derived from Morinda officinalis
by
Yan, Ming-Li
,
Chen, Yu-Chan
,
Zhang, Wei-Min
in
Alternaria - isolation & purification
,
Alternaria - metabolism
,
Alternaria sp
2017
Two new compounds isobenzofuranone A (1) and indandione B (2), together with eleven known compounds (3–13) were isolated from liquid cultures of an endophytic fungus Alternaria sp., which was obtained from the medicinal plant Morinda officinalis. Among them, the indandione (2) showed a rarely occurring indanone skeleton in natural products. Their structures were elucidated mainly on the basis of extensive spectroscopic data analysis. All of the compounds were evaluated with cytotoxic and α-glucosidase inhibitory activity assays. Compounds 11 and 12 showed significant inhibitory activities against four tumor cell lines; MCF-7, HepG-2, NCI-H460 and SF-268, with IC50 values in the range of 1.91–9.67 μM, and compounds 4, 5, 9, 10, 12 and 13 showed excellent inhibitory activities against α-glucosidase with IC50 values in the range of 12.05–166.13 μM.
Journal Article
Ptaquiloside and Pterosin B Levels in Mature Green Fronds and Sprouts of Pteridium arachnoideum
by
Soto-Blanco, Benito
,
Ribeiro, Debora da Silva Freitas
,
Keller, Kelly Moura
in
Animals
,
bracken fern
,
Brazil
2020
Pteridium arachnoideum, a fern of the Pteridium aquilinum species complex found in South America, is responsible for several different syndromes of poisoning. Cases of bovine enzootic hematuria and upper alimentary squamous cell carcinoma are both frequent occurrences in Brazil, whereas only bovine enzootic hematuria is noted with any frequency around the world. The reason for the high frequency of upper alimentary squamous cell carcinoma in Brazil is not currently known. One possible explanation may be the higher levels of ptaquiloside and pterosin B in Brazilian Pteridium than those present in the plant in other countries. However, these levels have not yet been determined in P. arachnoideum. Thus, the present study aimed to measure and compare ptaquiloside and pterosin B levels in mature green fronds and sprouts of P. arachnoideum collected from different locations in Brazil. Samples of P. arachnoideum were collected from the states of Minas Gerais and Rio Grande do Sul. A total of 28 mature leaf samples and 23 sprout samples were used. The mean concentrations of ptaquiloside and pterosin B present in the mature green fronds of P. arachnoideum ranged from 2.49 to 2.75 mg/g and 0.68 to 0.88 mg/g, respectively; in P. arachnoideum sprouts, mean concentrations of ptaquiloside and pterosin B ranged from 12.47 to 18.81 mg/g, and 4.03 to 10.42 mg/g for ptaquiloside and pterosin B, respectively. Thus, ptaquiloside and pterosin B levels in P. arachnoideum samples collected in Brazil were higher in sprouts than in mature green fronds, as observed in other countries. However, there was no variation in ptaquiloside levels among plants collected from different cities in Brazil. The high frequency of upper alimentary squamous cell carcinoma in Brazilian cattle may not be attributed to greater levels of ptaquiloside and pterosin B in P. arachnoideum than in other Pteridium species in other countries.
Journal Article
Postmortem distribution and redistribution of MDAI and 2-MAPB in blood and alternative matrices
by
Boxler, Martina I.
,
Gascho, Dominic
,
Oestreich, Andrea
in
2-MAPB
,
Adipose Tissue - chemistry
,
Adult
2017
•First case report involving MDAI and 2-MAPB.•Peripheral blood concentration was 38μg/L (MDAI) and 21μg/L (2-MAPB).•No significant postmortem concentration changes in peripheral and heart blood observed.
Intoxication cases involving new psychoactive substances (NPS) provide several challenges for forensic toxicologists as data on pharmacodynamic and pharmacokinetic properties are lacking, especially on potency and toxicity. Furthermore, reference values and information on postmortem redistribution (PMR) do not exist so far for most NPS. A fatal case involving the amphetamine-derivatives MDAI (5,6-methylenedioxy-2-aminoindane) and 2-MAPB (1-(benzofuran-2-yl)-N-methylpropan-2-amine) was investigated at the Zurich Institute of Forensic Medicine. At admission at the institute approx. 11h after death (first time point, t1), femoral and heart blood (right ventricle) was collected using computed tomography (CT)-guided biopsy sampling. At autopsy (t2), samples from the same body regions as well as various tissue samples were collected manually. In addition, an antemortem blood sample collected 6h before death was available. MDAI and 2-MAPB were quantified using a validated LC–MS/MS method. A significant concentration decrease between the antemortem and the first peripheral postmortem blood sample was observed, which most probably can be explained by remaining metabolism and excretion within the last 6h prior to death. No significant concentration change was observed between the two postmortem heart blood and peripheral blood samples. Accordingly, MDAI and 2-MAPB did not seem to undergo relevant postmortem redistribution in peripheral and heart blood in the presented case. This is the first study on postmortem redistribution of the new psychoactive substances MDAI and 2-MAPB. However, more studies covering more cases are necessary to generate universal statements on the PMR with these two NPSs.
Journal Article
Ptaquiloside in Irish Bracken Ferns and Receiving Waters, with Implications for Land Managers
by
O’Driscoll, Connie
,
Ramwell, Carmel
,
Hansen, Hans
in
Biological activity
,
bracken
,
Carcinogens
2016
Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk of ptaquiloside to drinking water was assessed by quantifying ptaquiloside in the receiving waters at three drinking water abstraction sites across Ireland and in bracken fronds surrounding the abstraction sites. We also investigated the impact of different management regimes (spraying, cutting and rolling) on ptaquiloside concentrations at plot-scale in six locations in Northern Ireland, UK. Ptaquiloside concentrations were determined using recent advances in the use of LC-MS for the detection and quantification of ptaquiloside. The results indicate that ptaquiloside is present in bracken stands surrounding drinking water abstractions in Ireland, and ptaquiloside concentrations were also observed in the receiving waters. Furthermore, spraying was found to be the most effective bracken management regime observed in terms of reducing ptaquiloside load. Increased awareness is vital on the implications of managing land with extensive bracken stands.
Journal Article
Donepezil distribution in postmortem cases and potential for redistribution
by
Iwase, Hirotaro
,
Nagasawa, Sayaka
,
Torimitsu, Suguru
in
acetylcholinesterase
,
Aged, 80 and over
,
Alzheimer disease
2015
•Donepezil (DPZ) was detected at high concentrations in postmortem specimens.•Central blood to peripheral blood ratio and liver to peripheral blood ratio of DPZ indicate postmortem redistribution.•Postmortem reduction in blood pH causes increased ionic forms of DPZ to be detected.
Donepezil (DPZ) is an acetylcholine-esterase inhibitor currently used as the frontline drug to treat Alzheimer's disease. The aim of this study was to investigate the possibility of postmortem redistribution (PMR) of DPZ, which could complicate the determination of cause of death in medico-legal cases. Additionally, metabolic enzyme DNA polymorphism, drug–drug interaction and the presence of lesions in metabolic and egestion organs were examined to eliminate the possibility of a high antemortem DPZ concentration. Subsequently, the average DPZ concentration of four sites of peripheral blood (right and left femoral artery and vein) was compared with central blood and liver DPZ concentrations in seven postmortem cases. DPZ concentrations ranged from 0.02 to 0.45μg/mL in the peripheral blood, 0.09–0.4μg/mL in central blood, and from 1.2 to 6.7μg/kg in the liver. In most specimens, the concentrations were higher than the therapeutic range (approximately 0.030–0.075μg/mL). DPZ central blood to peripheral blood (C/P) ratios averaged 1.73±1.02 (±standard deviation) while liver to peripheral blood (L/P) ratios were higher and averaged 17.5±7.25. It is documented that a C/P ratio of less than (or about) 1.0 and an L/P ratio less than 5 are not indicative of PMR, whereas a C/P ratio exceeding 2 and L/P ratio exceeding 20 highlight a propensity for significant PMR. Our data suggest that DPZ exhibits a moderate degree of PMR. Additionally, a lowered pH was found in all blood specimens (<6–6.75 in the peripheral blood and <6–6.66 in the central blood). This postmortem reduction in blood pH may increase the ionic forms of DPZ, resulting in a high blood DPZ concentration.
Journal Article
A validated capillary electrophoretic method for the determination of indacaterol and its application to a pharmaceutical preparation
by
Güray, Tufan
,
Tunçel, Muzaffer
,
Uysal, Ulku Dilek
in
Accuracy
,
buffers
,
Capillary electrophoresis
2018
Indacaterol is a new inhaled ultra-long acting β2-agonist. It has been recently approved in the European Union for the treatment of chronic obstructive pulmonary disease. This paper reports, for the first time, a method for the determination and validation of Indacaterol (IND) using an internal standard in capsules. Capillary electrophoretic separation was performed on an uncoated fused-silica capillary (50 cm effective length, 75 μm i.d.) and background electrolyte composed of 20 mmol L−1 of sodium tetraborate buffer, 15% (v/v) methanol (pH = 10.0) with the application of 20 kV of potential; 10 s at 5 × 103 N m−2 (50 mbar) of injection time; and wavelength of 200 nm and 25 °C of temperature. The linearity was evaluated in the range of 4.90 × 10−6 mol L−1 (2.50 μg mL−1) and 3.94 × 10−5 mol L−1 (20.00 μg mL−1), with R = 0.9993 for inter-day. LOD and LOQ values were 2.18 × 10−8 mol L−1 (0.011 μg mL−1) and 7.25 × 10−8 mol L−1 (0.037 μg mL−1) for inter-day, respectively. The precision values were 0.50–1.06% for intra-day and 2.12% for inter-day as RSD%. The accuracy was tested by the standard addition method with the recovery values being between 98.79 and 99.09 as percentages with RSD% interval of 0.01–0.80. The developed method was validated according to ICH guidelines. Indacaterol was successfully determined in Arcapta® capsule dosage form by the validated CE method with a relative error of 0.28%. The result was within the requirements of the USP 34-NF29. Therefore, the validated method may be used for the determination of Indacaterol in its capsules in quality control laboratories.
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•Analysis of recently approved pharmaceutic in the European Union and FDA.•Newly developed and fully validated CE method for the determination of indacaterol.•For the first time, CZE method for indacaterol in Arcapta®.
Journal Article
Development and validation of an LC-ESI-MS/MS method for the triple reuptake inhibitor indatraline enabling its quantification in MS Binding Assays
2015
We herein present the first LC-MS/MS quantification method for indatraline, a highly potent nonselective inhibitor of the three monoamine transporters (for dopamine, DAT; norepinephrine, NET; serotonin, SERT), and its application to MS Binding Assays. For HPLC, an R18 column with a mobile phase composed of acetonitrile and ammonium bicarbonate buffer (5 mmol L
-1
, pH 10.0) in a ratio of 90:10 (v/v) at a flow rate of 600 μL min
-1
was used. Recording indatraline at
m/z
292.2/261.0 and (
2
H
7
)-indatraline, employed as internal standard, at
m/z
299.2/268.0 allowed reliable quantification from 5 pmol L
−1
(LLOQ) to 5 nmol L
−1
in biological matrices without additional sample preparation. Validation of the developed quantification method showed that selectivity, calibration standard curve, accuracy, as well as precision meet the criteria of the CDER guideline. Applying this method to mass spectrometry (MS) Binding Assays, a label-free MS-based alternative to conventional radioligand binding assays, binding of indatraline’s eutomer, (1
R
,3
S
)-indatraline, towards NET could be characterized directly for the first time, revealing an equilibrium dissociation constant (
K
d
) of 805 pmol L
−1
. Additionally, it could be shown that the established MS Binding Assays enable characterization of test compounds in competition experiments. As the established setup is based on a 96-well format and an LC MS/MS method with a short chromatographic cycle time (1.5 min), the developed MS Binding Assays enable considerable throughput and are therefore well suited as substitute for corresponding radioligand binding assays.
Journal Article
The effect of zinc chloride, humidity and the substrate on the reaction of 1,2-indanedione–zinc with amino acids in latent fingermark secretions
by
Shimmon, Ronald
,
Lennard, Chris
,
Spindler, Xanthe
in
1,2-indanedione
,
Amino acids
,
Amino Acids - analysis
2011
Anecdotal evidence from forensic practitioners and studies conducted under controlled conditions have indicated that the reaction between 1,2-indanedione and the amino acids present in latent fingermark deposits is highly susceptible to ambient humidity. The addition of catalytic amounts of zinc chloride to the 1,2-indanedione working solution – usually in the order of 1:25 to 1:4 molar ratio (indanedione:zinc) – significantly improves the colour and luminescence of fingermarks treated under dry conditions but appears to have a negligible effect on fingermarks treated in humid environments. The results presented in this paper confirmed that zinc(II) ions added to the 1,2-indanedione working solution act as a Lewis acid catalyst, stabilising a key intermediate during a rate-limiting hydrolysis step. Furthermore, studying the reaction using a chromatography-grade cellulose substrate method previously reported confirmed that cellulose substrates play a major role in facilitating the indanedione-amino acid reaction by acting as a surface catalyst in the early stages of the reaction and by directing the formation of the desired luminescent product (Joullié’s Pink).
Journal Article
A New Facile Synthesis of D4-Pterosin B and D4-Bromopterosin, Deuterated Analogues of Ptaquiloside
by
Attya, Mohamed
,
Sindona, Giovanni
,
Tagarelli, Antonio
in
Acids
,
Carcinogens
,
Carcinogens - analysis
2012
Ptaquiloside (Pta) is a potent carcinogen present in bracken fern and in soil matrices, that can potentially leach to the aquatic environment. More recently its presence in the milk of different farm animals has been reported. Pterosin B (Ptb) and bromopterosin (BrPt) represent the most convenient analogues in the detection of ptaquiloside by mass spectrometry. Pterosin sesquiterpenes are also involved in many patented biomedical protocols. In this work we introduce a new and convenient approach to the synthesis in three steps and more than 80% yield of d4-pterosin B (d4-Ptb) and d4-bromopterosin (d4-BrPt), useful as internal standards in the quantification of ptaquiloside.
Journal Article
Stir-bar-sorptive extraction and liquid desorption combined with large-volume injection gas chromatography-mass spectrometry for ultra-trace analysis of musk compounds in environmental water matrices
by
Silva, Ana Rita M
,
Nogueira, J. M. F
in
Analysis methods
,
Analytical Chemistry
,
Applied sciences
2010
Stir-bar-sorptive extraction with liquid desorption followed by large-volume injection and capillary gas chromatography coupled to mass spectrometry in selected ion monitoring acquisition mode (SBSE-LD/LVI-GC-MS(SIM)) has been developed to monitor ultra-traces of four musks (celestolide (ADBI), galaxolide (HHCB), tonalide (AHTN) and musk ketone (MK)) in environmental water matrices. Instrumental calibration (LVI-GC-MS(SIM)) and experimental conditions that could affect the SBSE-LD efficiency are discussed. Assays performed on 30-mL water samples spiked at 200 ng L⁻¹ under optimized experimental conditions yielded recoveries ranging from 83.7 ± 8.1% (MK) to 107.6 ± 10.8% (HHCB). Furthermore, the experimental data were in very good agreement with predicted theoretical equilibria described by octanol-water partition coefficients (K PDMS/W ≈ K O/W). The methodology also showed excellent linear dynamic ranges for the four musks studied, with correlation coefficients higher than 0.9961, limits of detection and quantification between 12 and 19 ng L⁻¹ and between 41 and 62 ng L⁻¹, respectively, and suitable precision (< 20%). Application of this method for analysis of the musks in real water matrices such as tap, river, sea, and urban wastewater samples resulted in convenient selectivity, high sensitivity and accuracy using the standard addition methodology. The proposed method (SBSE-LD/LVI-GC-MS(SIM)) was shown to be feasible and sensitive, with a low-sample volume requirement, for determination of musk compounds in environmental water matrices at the ultra-trace level, overcoming several disadvantages presented by other sample-preparation techniques.
Journal Article