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Uhplc-hrms and gc-ms screening of a selection of synthetic cannabinoids and metabolites in urine of consumers
Full text linkBackground and Objectives: The use of synthetic cannabinoids has increased around the world. As a result, the implementation of accurate analysis in human biological matrices is relevant and fundamental. Two different analytical technologies, ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) and high-sensitivity gas chromatography-mass spectrometry (GC-MS) were used for the determination of three synthetic cannabinoids JWH-122, JWH 210, UR-144 and their metabolites in urine of consumers. Materials and Methods: Sample preparation included an initial hydrolysis with β-glucuronidase and liquid-liquid extraction. The UHPLC-HRMS method included a Kinetex 2.6 u Biphenyl 100A (100 × 2.1 mm, 2.6 μm) (Phenomenex, Italy) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode was used (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m × 250 μm i.d, film thickness 0.25 μm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Results: Both methods have been successfully used for screening of parent synthetic cannabinoids and their metabolites in urine samples of consumers. Conclusions: The screening method applied JWH-122, JWH-210, UR-144 and their metabolites in urine of consumers can be applied to other compounds of the JWH family
La giurisprudenza sovranazionale tra tutela della libertà religiosa delle organizzazioni di tendenza e protezione dei diritti del lavoratore
No full textIs GHB-glucuronide useful as a biomarker for the exogenous use of GHB?
No full textDetection of gamma-hydroxybutyric acid (GHB) in biological matrices of conscious and unconscious consumers has become crucial in many clinical and forensic settings, due to its increasing use for recreational purposes, including “chemsex” and drug-facilitated sexual assault. It has to be mentioned that the drug itself as well as its precursors, gamma- butyrolactone (GBL) and 1,4-butanediol (1,4-BD), are currently restricted in several countries (e.g. United States, United Kingdom, Italy) and also the UN Commission on Narcotic Drugs has listed GHB among Psychotropic Substances. The main issue in the analytical determination of GHB concentrations in biological fluids (e.g. blood, urine, cerebrospinal fluid) and in keratin matrices (e.g. hair, nails) derives from the importance of being able to distinguish endogenous GHB from exogenous administration of an illegal drug, as reported above, and in the latter hypothesis, the challenge is the detection of single doses unknowingly consumed by victims of suspected sexual violence. GHB naturally occurs in the human body, so caution must be taken in the interpretation of positive results. Furthermore, GHB has a narrow window of detection (about 3-12 h in both blood and urine) and quickly reaches concentrations overlapping the endogenous ones. In the search of a biomarker of its use with a longer detection window, the in vivo existence of a glucuronated GHB metabolite (GHB-glucuronide) was investigated9. Successfully, the glucuronated metabolite was determined in different biological matrices (plasma, urine, hair, nails, cerebrospinal fluid and whole blood) with hyphenated techniques and a longer window of detection than the parent drug was demonstrated. Unfortunately, in all the reported studies, GHB-glucuronide was quantified in negligible concentrations regardless of whether the parent drug had been administered as a medication or abused as a recreational drug. This evidence has raised some questions concerning the real importance of this metabolic pathway for GHB and in agreement with the conclusions of reported studies, it is likely that this glucuronated metabolite does not provide any diagnostic information regarding GHB exogenous intake. However, an important aspect that has to be taken into account is that the metabolite analyzed to date is the glucuronate at the level of the hydroxyl group of GHB and not the glucuronate at the level of the carboxylic group, due to the unavailability of the standard compound. Therefore, the possibility of monitoring the carboxylic glucuronated metabolite of GHB, when the chemical standard will be available, could allow to evaluate if this other metabolite is useful in detecting GHB exogenous administration with a better diagnostic time-frame
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Assessment of prenatal exposure to ethanol by meconium toxicology: resultsof an italian multicentric study
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