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1.
An HPLC‐ECD method for monoamines and metabolites quantification in cuttlefish (cephalopod) brain tissue
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Flavie Bidel Sophie Corvaisier Christelle Jozet‐Alves Ivannah Pottier François Dauphin Nadège Naud Cécile Bellanger 《Biomedical chromatography : BMC》2016,30(8):1175-1183
The cuttlefish belongs to the mollusk class Cephalopoda, considered as the most advanced marine invertebrates and thus widely used as models to study the biology of complex behaviors and cognition, as well as their related neurochemical mechanisms. Surprisingly, methods to quantify the biogenic monoamines and their metabolites in cuttlefish brain remain sparse and measure a limited number of analytes. This work aims to validate an HPLC‐ECD method for the simultaneous quantification of dopamine, serotonin, norepinephrine and their main metabolites in cuttlefish brain. In comparison and in order to develop a method suitable to answer both ecological and biomedical questions, the validation was also carried out on a phylogenetically remote species: mouse (mammals). The method was shown to be accurate, precise, selective, repeatable and sensitive over a wide range of concentrations for 5‐hydroxyindole‐3‐acetic acid, serotonin, dopamine, 3,4‐dihydroxyphenylacetic acid and norepinephrine in the both extracts of cuttlefish and mouse brain, though with low precision and recovery for 4‐hydroxy‐3‐methoxyphenylethylene glycol. Homovanillic acid, accurately studied in rodents, was not detectable in the brain of cuttlefish. Overall, we described here the first fully validated HPLC method for the routine measurement of both monoamines and metabolites in cuttlefish brain. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
2.
Flavie Peudru Remi Legay Jean-François Lohier Vincent Reboul Mihaela Gulea 《Tetrahedron》2012,68(44):9016-9022
A new efficient and general synthetic methodology to access γ-aminothiols was investigated and developed. 1,3-Thiazines were used as convenient precursors and were prepared by a fast microwave-assisted three-component reaction (3CR) of thioamides, aldehydes, and alkenes. The transformation of thiazines into aminothiols was achieved via a thiazinium salt hydrolysis, in three very facile steps. 相似文献
3.
Markus Suta Flavie Lavoie‐Cardinal Claudia Wickleder 《Angewandte Chemie (International ed. in English)》2020,59(27):10949-10954
Inorganic hosts, such as SrB4O7 or certain nitrides, intrinsically stabilize Eu2+ even when the dopant is an Eu3+‐based precursor and reducing conditions are not employed in the synthesis. Although this concept is well known in the synthesis of phosphorescent materials, the mechanistic details are scarcely understood. Herein, we demonstrate that trapped charge carriers, such as color centers, can also act as redox partners to stabilize certain oxidation states of activators. Eu‐activated CsMgCl3 and CsMgBr3 are used as examples. Upon doping with EuCl3 and in the absence of reducing conditions during the synthesis, dominant cyan or green luminescence from Eu2+ ions was observed. Photoluminescence spectroscopy at 10 K revealed that the reduction is correlated to color centers localized at defects. Although defects are typically undesired in phosphors, we have shown that their role may be underestimated and they could be used on purpose in the preparation of selected inorganic phosphors. 相似文献
4.
Ekaterina P. Nesterenko Pavel N. Nesterenko Damian Connolly Flavie Lacroix Brett Paull 《Journal of chromatography. A》2010,1217(14):2138-2146
A new method for the fixation of polymethacrylate monoliths within titanium tubing of up to 0.8 mm I.D. for use as a chromatographic column under elevated temperatures and pressures is described. The preparation of butyl methacrylate–ethylene dimethacrylate-based monolithic stationary phases with desired porous structures was achieved within titanium tubing with pre-oxidised internal walls. The oxidised titanium surface was subsequently silanised with 3-trimethoxysilylpropyl methacrylate resulting in tight bonding of butyl methacrylate porous monolith to the internal walls, providing stationary phase stability at column temperatures up to 110 °C and at operating column pressure drops of >28 MPa. The titanium housed monoliths exhibited a uniform and dense porous structure, which provided peak efficiencies of up to 59,000 theoretical plates per meter when evaluated for the separation of small molecules in reversed-phase mode, under optimal conditions (achieved at 15 μL/min and temperature of 110 °C for naphthalene with a retention factor, k = 0.58). The developed column was applied to the reversed-phase isocratic separation of a text mixture of pesticides. 相似文献
5.
A. Bresson Y. Bidel P. Bouyer B. Leone E. Murphy P. Silvestrin 《Applied physics. B, Lasers and optics》2006,84(4):545-550
This paper is an introduction to the following articles in the scope of quantum mechanics for space study initiated by ESA and lead by ONERA. The context of quantum mechanics for space is summarised, and the fields under development are briefly introduced. Technological applications of quantum mechanics in space are explored and some tests of quantum mechanics are outlined. We also give a brief presentation of the opto-electronic section of the European Space Agency, and the technology development activities it carries out, with particular emphasis on those activities related to the topics of interest of the quantum mechanics in space workshop. As an example, a summary of two ESA studies on gravity gradiometry and their relevance to the field of atomic interferometry is given. In view of the scientific requirements, derived for both Earth observation and planetology for future space missions, atom interferometry shows promise and may provide an advantage over currently available accelerometer and inertial sensor systems. PACS 04.25.Nx; 04.80.Cc; 07.60.Ly; 95.30.Sf 相似文献
6.
Electric control of droplets in microfluidic devices 总被引:1,自引:0,他引:1
7.
Alexandre Amin Philippe Bourget Flavie Ader Fabrice Vidal Cindy Neuzillet Arlette Baillet‐Guffroy 《Journal of Raman spectroscopy : JRS》2015,46(12):1283-1290
The purpose of this study was to develop a Raman spectroscopy (RS) method as an effective tool for the non‐intrusive pre‐delivery analytical quality control (AQC) of two camptothecin analogs, i.e. irinotecan (IRI) and topotecan (TPT), which are prescribed and compounded at the hospital. Following a phase of analytical pre‐validation, based on the actual conditions of use of the analogs, the protocol was validated and compared with the reference high‐performance liquid chromatography (HPLC) method. For IRI, AQC by RS has been validated in ranges from 0.94 to 3.27 mg/ml in saline solutions and from 0.89 to 3.30 mg/ml in dextrose solutions. These ranges recover the entire therapeutic concentrations encountered in clinical practice, i.e. 1.08–2.8 mg/ml. The RS and HPLC methods were validated by calculating the accuracy profile and provided excellent results for the analytical validation key criteria. The Spearman and Kendall correlation tests (p‐value < 1.10−11) and the statistical studies performed on the Bland and Altman graphs confirm a strong correlation between RS and HPLC results. However, we show that a routine apparatus is unable to quantify TPT therapeutic concentrations ranging between 25 and 50 µg/ml but that a sufficiently powerful RS bench is able to detect and quantify TPT. Overall, these results confirm the potential of the RS option for future innovative applications. Owing to its analytical and practical qualities, this promising method contributes to the improvement of the safety of the medication circuit at the hospital and to the protection of caregivers and their working environment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
Bidel LP Meyer S Goulas Y Cadot Y Cerovic ZG 《Journal of photochemistry and photobiology. B, Biology》2007,88(2-3):163-179
Chlorophyll fluorescence (ChlF) excitation spectra were measured to assess the UV-sunscreen compounds accumulated in fully expanded leaves of three woody species belonging to different chemotaxons, (i.e. Morus nigra L., Prunus mahaleb L. and Lagerstroemia indica L.), grown in different light microclimates. The logarithm of the ratio of ChlF excitation spectra (logFER) between two leaves acclimated to different light microclimates was used to assess the difference in epidermal absorbance (EAbs). EAbs increased with increasing solar irradiance intercepted for the three species. This epidermal localisation of UV-absorbers was confirmed by the removal of the epidermis. It was possible to simulate EAbs as a linear combination of major phenolic compounds (Phen) identified in leaf methanol extracts by HPLC-DAD. Under UV-free radiation conditions, shaded leaves of M. nigra accumulated chlorogenic acid. Hydroxybenzoic acid (HBA) derivatives and hydroxycinnamic acid (HCA) derivatives greatly increased with increasing PAR irradiance under the low UV-B conditions found in the greenhouse. These traits were also observed for the HCA of the two other species. Flavonoid (FLAV) accumulation started under low UV-A irradiance, and became maximal in the adaxial epidermis of sun-exposed leaves outdoors. A decrease in the amount of HCA was observed concomitantly to the intense accumulation of FLAV for both leaf sides of the three species. Judging from the logFER, under low UV-B conditions, larger amounts of HCA are present in the epidermis in comparison to FLAV for the three species. Upon transition from the greenhouse to full sunlight outdoors, there was a decrease in leaf-soluble HCA that paralleled FLAV accumulation in reaction to increasing solar UV-B radiation in the three species. In M. nigra, that contains large amounts of HCA, the logFER analysis showed that this decrease occurred in the adaxial epidermis, whereas the abaxial epidermis, which is protected from direct UV-B radiation, continued to accumulate large amounts of HCA. 相似文献
9.
O. Carraz F. Lienhart R. Charrière M. Cadoret N. Zahzam Y. Bidel A. Bresson 《Applied physics. B, Lasers and optics》2009,97(2):405-411
We propose a compact and robust laser system at 780 nm for onboard atomic inertial sensors based on rubidium atom interferometry.
The principle of this system consists in doubling the frequency of a telecom fiber bench at 1560 nm. The same laser source
is used to achieve a magneto-optical trap, matter–wave interferences, and the atomic detection. An atomic gravimeter has been
realized and the laser system has been validated under hyper- and microgravity. 相似文献
10.
G. Stern B. Battelier R. Geiger G. Varoquaux A. Villing F. Moron O. Carraz N. Zahzam Y. Bidel W. Chaibi F. Pereira Dos Santos A. Bresson A. Landragin P. Bouyer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):353-357
We describe the operation of a light pulse interferometer using cold 87Rb atoms in reduced gravity. Using a series of two Raman transitions induced by light pulses, we have obtained Ramsey fringes
in the low gravity environment achieved during parabolic flights. With our compact apparatus, we have operated in a regime
which is not accessible on ground. In the much lower gravity environment and lower vibration level of a satellite, our cold
atom interferometer could measure accelerations with a sensitivity orders of magnitude better than the best ground based accelerometers
and close to proven spaced-based ones. 相似文献