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Local application of aqueous phytohormonal solution (0.1 ml of various concentrations, from 50 to 0.025 mg‐l−1, of IAA, 2,4‐D, NAA, BAP, GA3) on isolated leaves influences the direction of ion transport. All tested hormones are efficient but the action depends upon the ionic species [positive action with 32P, 35S, 36Rb (K), but null with 45Ca or 46Cl]. The movement of ions occurs through the phloem tissue and is not a cell‐to‐cell transfer. Competition between different parts of the leaf is demonstrated (a) between petiole which appears to be an important attractive centre and other parts of the leaf; (b) in a depetioloted leaf, between different centres induced by different phytohormones. In this respect, GA3 appears to be the most efficient hormone in the tested material — leaves of Pelargonium zonale (L.) Aiton. The effects on directional transport are discussed in relation to other processes controlled by hormones, for instance growth, senescence, protein synthesis. A direct relation of directional transport with growth or delay of senescence may be discarded. The value of isolated leaves as simplified experimental systems is underlined by the fact that weak hormonal doses are efficient (0.025 mg.l for GA3 and 0.5 mg.1 for 2,4‐D) as compared to the higher doses used in other plant systems. [ABSTRACT FROM AUTHOR]

Because of logistics and cost constraints, monitoring of the compliance to antimalarial chemoprophylaxis by the quantitation of drugs in biological samples is not a simple operation on the field. Indeed, analytical devices are fragile to transport and must be used in a perfectly controlled environment. This is also the case for reagents and supplies, and the waste management is constraining. Thus, samples should be repatriated. They should be frozen after collection and transported with no rupture in the cold chain. This is crucial to generate available and interpretable data but often without any difficulties. Hence, to propose an alternative solution easier to implement, a quantitation method of determining doxycycline in urine has been validated using a volumetric absorptive microsampling (VAMS ® ) device. As blotting paper, the device is dried after collection and transferred at room temperature, but contrarily to dried spot, the collection volume is perfectly repeatable. Analysis of VAMS ® was performed with a high-performance liquid chromatography coupled to a mass spectrometer. The chromatographic separation was achieved on a core-shell C18 column. The mean extraction recovery was 109% (mean RSD, 5.4%, n  = 6) for doxycycline and 102% (mean RSD, 7.0%) for the internal standard. No matrix effect has been shown. Within-run as within-day precision and accuracy were, respectively, below 14% and ranged from 96 to 106%. The signal/concentration ratio was studied in the 0.25-50  µ g/mL range, and recoveries from back-calculated concentrations were in the 96-105% range (RSD < 11.0%). The RSD on slope was 10%. To achieve the validation, this new quantitation method was applied to real samples. In parallel, samples were analyzed directly after a simple dilution. No statistical difference was observed, confirming that the use of VAMS ® is an excellent alternative device to monitor the doxycycline compliance., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Mylène Penot et al.)

Besides their development for therapeutic purposes, non-steroidal selective androgen receptor modulators (non-steroidal SARMs) are also known to impact growth-associated pathways as ligands of androgenic receptors (AR). They present a potential for abuse in sports and food-producing animals as an interesting alternative to anabolic androgenic steroids (AAS). These compounds are easily available and could therefore be (mis)used in livestock production as growth promoters. To prevent such practices, dedicated analytical strategies should be developed for specific and sensitive detection of these compounds in biological matrices. The present study focused on Bicalutamide, a non-steroidal SARM used in human treatment of non-metastatic prostate cancer because of its anti-androgenic activity exhibiting no anti-anabolic effects. To select the most appropriate matrix to be used for control purposes, different animal matrices (urine and faeces) have been investigated and SARM metabolism studied to highlight relevant metabolites of such treatments and establish associated detection time windows. The aim of this work was thus to compare the urinary and faecal eliminations of bicalutamide in a calf, and investigate phase I and II metabolites. The results in both matrices showed that bicalutamide was very rapidly and mainly excreted under its free form. The concentration levels were observed as higher in faeces (ppm) than urine (ppb); although both matrices were assessed as suitable for residue control. The metabolites found were consistent with hydroxylation (phase I reaction) combined or not with glucuronidation and sulfation (phase II reactions). Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

Selective androgen receptor modulators (SARMs) are a novel class of androgen receptor ligands. They are intended to exhibit the same kind of effects as androgenic drugs, like anabolic steroids, but be much more selective in their action, targeting particular tissues without any undesirable effects on others. While the main applications of these synthetic substances are for therapeutic purposes, they also have a high potential for misuse in veterinary practice and the sporting world. In order to guarantee for consumers with food from animal origin that it is free from any residues of such compounds, analytical strategies are required to ensure safe food and also to enable fair trade between producers. In this context an animal experiment involving bovines administered with enobosarm was conducted to provide the study with biological matrices. Different animal matrices (urine and faeces) were investigated to select the most appropriate matrix for use for control purposes, in terms of metabolite relevance and detection time window. Based on ultra-high-pressure liquid chromatography (UHPLC) with tandem mass spectrometry (LC-MS/MS) this work highlighted the presence of sulfonated and glucuronated-conjugated forms of the molecule in the urine of treated animals. Enobosarm could be detected in urine up to 9 days after the administration when samples underwent phase II hydrolysis. Faeces was demonstrated to be the main matrix of excretion of enobosarm since values up to 500 times higher compared with urine could be detected for 21 days. There was no difference between the kinetic profiles when a deconjugation step was or was not was applied.

Currently under development for therapeutic purposes in human medicine, non-steroidal selective androgen receptor modulators (non-steroidal SARMs) are also known to impact growth associated pathways. As such, they present a potential for abuse in sports and food-producing animals as interesting alternative anabolic substances. Forbidden since 2008 by the World Anti-Doping Agency (WADA) these compounds are however easily available and could be (mis)used in livestock production as growth promoters. To prevent such practices, dedicated analytical strategies have to be developed for specific and sensitive detection of these compounds in biological matrices. Using an innovative analytical platform constituted of supercritical fluid chromatography coupled to ion mobility-mass spectrometry, the present study enabled efficient separation and identification in urine of 4 of these drugs (andarine, bicalutamide, hydroxyflutamide, and enobosarm) in accordance with European Union criteria (Commission Decision 2002/657/EC). Besides providing information about compounds structure and behaviour in gas phase, such a coupling enabled reaching low limits of detection (LOD < 0.05 ng.mL -1 for andarine and limits of detection < 0.005 ng.mL -1 for the three others) in urine with good repeatability (CV < 21 %). The workflow has been applied to quantitative determination of enobosarm elimination in urine of treated bovine (200 mg, oral). Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

(45)Ca long-distance transport was studied within various groups of plants (higher plants and marine Algae) in relation to the absorption process at the level of the source organs. The purpose was to determine whether the well-known absence of Ca(2+) movement might be attributed to some particularity of the cell absorption. - The results obtained lead to the following conclusions: 1) In higher plants, the translocation of (45)Ca applied to the leaf is possible; it occurs through the phloem (heat-girdling). After a darkness-pretreatment, the translocation decreases significantly while the absorption in the leaf does not; this allows us to distinguish between the two processes and to underline the relationship which exists between the long distance transport and the phloem metabolism. The significant decrease of the translocation after a local application of cycloheximide to the stem underlines the dependence of the phloem transport on the protein metabolism. 2) In the case of Algae, (45)Ca migrates very easily in Ascophyllum nodosum, whereas in Laminaria digitata the (45)Ca immobility contrasts with the very high mobility of (32)P. 3) In every case studied (leaf, thallus) the lack of effect on the calcium absorption of the different factors used (low temperature, darkening, metabolic inhibitors: KCN, CCCP, CHM, etc.) is in agreement with a non-metabolic nature of the calcium ion uptake.

An autoradiographic study of the rooted shoots of Tradescantia viridis (=T. albiflora Kunth emend. Brueckn.) showed a high speed translocation of (86)Rb applied to a leaf for short periods of time (5 to 2.5 min).The speed of this translocation (between 840 and 1.440 cm h(-1)) speaks for the existence of a very rapid phloem component translocating ions to an active sink, represented here by the growing roots.Pretreatment with cycloheximide (48 h, 50 mg l(-1)) decreases the quantity of this long distance transport but not the velocity.

(32)P was applied to a Laminaria digitata thallus and the pattern of (32)P phosphorylated compounds was studied, as a function of time, in the different tissues involved in translocation, i.e. source, pathway and sinks. The results showed that, 3 hours after absorption by the uptake region (lamina), the bulk of the radioactivity was incorporated into organic compounds (70 to 80% of total (32)P taken up), hexose monophosphates being the heaviest labelled. Further change in that region was marked by an accumulation of (32)P in the inorganic pool (65 to 70% after 13 days). Conversely, the (32)P pattern in the medulla of the stipe, which initially showed a similar pattern to the uptake region, did not vary during translocation. The pattern of (32)P distribution into sinks (growing stipe peripheral tissue or hapteron) leads to accumulation of the radioactive element in inorganic and acid-insoluble fractions. These results are discussed in terms of comparative distribution of (32)P in the different parts of the thallus and suggest that phosphate moves as Pi in that alga.