51 research outputs found
Finding the proverbial needle: Non-targeted screening of synthetic opioids in equine plasma.
Synthetic opioids are a class of compounds that are of particular concern due to their high potency and potential health impacts. With the relentless emergence of new synthetic opioid derivatives, non-targeted screening strategies are required that do not rely on the use of library spectra or reference materials. In this study, product ion searching, and Kendrick mass defect analysis were investigated for non-targeted screening of synthetic opioids. The estimated screening cut-offs for these techniques ranged between 0.05 and 0.1 ng/mL. These techniques were designed to not be reliant on a particular vendor's software, meaning that they can be applied to existing drug screening protocols, without requiring the development and validation of new analytical procedures. The efficacy of the developed techniques was tested through blind trials, with spiked samples inserted amongst authentic plasma samples, which demonstrated the usefulness of these methods for high-throughput screening. The use of a non-targeted screening workflow that contains complementary techniques can increase the likelihood of detecting compounds of interest within a sample, as well as the confidence in detections that are made
How was apical growth regulated in the ancestral land plant? Insights from the development of non seed plants
Land plant life cycles are separated into distinct haploid gametophyte and diploid sporophyte stages. Indeterminate apical growth evolved independently in bryophyte (moss, liverwort, and hornwort) and fern gametophytes, and tracheophyte (vascular plant) sporophytes. The extent to which apical growth in tracheophytes co-opted conserved gametophytic gene networks, or exploited ancestral sporophytic networks, is a long-standing question in plant evolution. The recent phylogenetic confirmation of bryophytes and tracheophytes as sister groups has led to a reassessment of the nature of the ancestral land plant. Here, we review developmental genetic studies of apical regulators and speculate on their likely evolutionary history
Evaluation of LC-QqQ-MS and LC-QToF-MS for the analysis of illicit drug residues in wastewater
High-throughput screening for target compounds in smokeless powders using online-SPE tandem mass spectrometry
© 2019, © 2019 Australian Academy of Forensic Sciences. The detection and quantification of compounds present in smokeless powders plays an important role in various fields such as environmental and forensic science. Often, time and labour consuming sample preparation techniques such as solid phase extraction (SPE) are required to facilitate either pre-concentration or sample clean-up with complex matrices. This paper describes the first application of the completely automated online SPE system RapidFire® connected to a triple quadrupole mass spectrometer for smokeless powder/gunshot residue analysis. The optimized method involved sample loading during 2000 ms using UP water (0.1% formic acid) at a flowrate of 1.25 mL/min on a Type C C18 cartridge followed by elution of the target compounds for 3000 ms using IPA (0.1% formic acid) at 0.75 mL/min. Target compounds were detected in soil (DPA, 2-NDPA, EC, NG, 2,4-DNT) and cotton swabs (NG) in only 8 seconds per sample with detection limits of 0.223 ppm (DPA), 0.104 ppm (2-NDPA), 0.0949 ppm (EC), 0.187 ppm (NG) and 0.128 ppm (2,4-DNT). The presented method showed promising results for the analysis of five target analytes in soil samples. Further optimisations can extend the analysis to other sample matrices and include more analytes potentially present in smokeless powders and GSR
Towards an untargeted mass spectrometric approach for improved screening in equine antidoping.
The emergence of novel doping agents is a continuous issue for analysts who aim to maintain the integrity of horseracing together with the well-being and safety of the animals and riders involved. Untargeted mass spectrometric analysis presents a potential improvement for antidoping as it enables the detection of compounds being indirectly affected by an administered drug. In this study, liquid chromatography-high-resolution mass spectrometry was used to investigate a 12-horse administration study of the synthetic opioid, butorphanol. A mass spectrometric workflow capable of detecting metabolic differences for an extended period of time was successfully developed. This proof-of-concept study demonstrates the potential of untargeted workflows to provide a list of biomarkers of exposure and effect that are indicative of drug administration which may be implemented into routine testing for improved doping control
A first estimate of the structure and density of the populations of pet cats and dogs across Great Britain
<div><p>Policy development, implementation, and effective contingency response rely on a strong evidence base to ensure success and cost-effectiveness. Where this includes preventing the establishment or spread of zoonotic or veterinary diseases infecting companion cats and dogs, descriptions of the structure and density of the populations of these pets are useful. Similarly, such descriptions may help in supporting diverse fields of study such as; evidence-based veterinary practice, veterinary epidemiology, public health and ecology. As well as maps of where pets are, estimates of how many may rarely, or never, be seen by veterinarians and might not be appropriately managed in the event of a disease outbreak are also important. Unfortunately both sources of evidence are absent from the scientific and regulatory literatures. We make this first estimate of the structure and density of pet populations by using the most recent national population estimates of cats and dogs across Great Britain and subdividing these spatially, and categorically across ownership classes. For the spatial model we used the location and size of veterinary practises across GB to predict the local density of pets, using client travel time to define catchments around practises, and combined this with residential address data to estimate the rate of ownership. For the estimates of pets which may provoke problems in managing a veterinary or zoonotic disease we reviewed the literature and defined a comprehensive suite of ownership classes for cats and dogs, collated estimates of the sub-populations for each ownership class as well as their rates of interaction and produced a coherent scaled description of the structure of the national population. The predicted density of pets varied substantially, with the lowest densities in rural areas, and the highest in the centres of large cities where each species could exceed 2500 animals.km<sup>-2</sup>. Conversely, the number of pets per household showed the opposite relationship. Both qualitative and quantitative validation support key assumptions in the model structure and suggest the model is useful at predicting the populations of cats at geographical scales important for decision-making, although it also indicates where further research may improve model performance. In the event of an animal health crisis, it appears that almost all dogs could be brought under control rapidly. For cats, a substantial and unknown number might never be bought under control and would be less likely to receive veterinary support to facilitate surveillance and disease management; we estimate this to be at least 1.5 million cats. In addition, the lack of spare capacity to care for unowned cats in welfare organisations suggests that any increase in their rate of acquisition of cats, or any decrease in the rate of re-homing might provoke problems during a period of crisis.</p></div
Comparison of empirical and modelled densities of cats.
<p>Data from Sims <i>et al</i>. (2008) as solid black markers; Data from Thomas <i>et al</i>. (2012) as solid blue markers. Four notable data points (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0174709#sec011" target="_blank">Discussion</a>) shown as diamonds. Predicted densities shown as a red line for comparison.</p
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