[Cannabidiol (CBD): Analytical and toxicological aspects]. / Le cannabidiol (CBD) : aspects analytiques et toxicologiques.

Cannabidiol (CBD) is a phytocannabinoid present in cannabis, obtained either by extraction from the plant or by synthesis. The latter has the advantage of being pure and contains few impurities, unlike CBD of plant origin. It is used by inhalation, ingestion or skin application. In France, the law stipulates that specialties containing CBD may contain up to 0.3% of tetrahydrocannabinol (THC), the psychoactive principle of cannabis. From an analytical point of view, it is therefore important to be able to quantify the two compounds as well as their metabolites in the various matrices that can be used clinically or forensically, in particular saliva and blood. The transformation of CBD into THC, which has long been suggested, appears to be an analytical artifact under certain conditions. CBD is not without toxicity, whether acute or chronic, as seems to attest to the serious adverse effects recorded by pharmacovigilance during the experiment currently being conducted in France by the Agence Nationale de Sécurité du Médicament et des Produits de Santé. Although CBD does not seem to modify driving abilities, driving a vehicle after consuming CBD containing up to 0.3% THC, and sometimes much more in products bought on the internet, can lead to a positive result in screening and confirmation tests by law enforcement agencies, whether salivary or blood tests, and therefore lead to a legal sanction.

Cannabis in Adolescence: Lasting Cognitive Alterations and Underlying Mechanisms.

Cannabis consumption during adolescence is an area of particular concern, owing to changes in the social and political perception of the drug, and presents a scientific, medical, and economic challenge. Major social and economic interests continue to push toward cannabis legalization as well as pharmaceutical development. As a result, shifting perceptions of both legal and illicit cannabis use across the population have changed the collective evaluation of the potential dangers of the product. The wave of cannabis legalization therefore comes with new responsibility to educate the public on potential risks and known dangers associated with both recreational and medical cannabis. Among these is the risk of long-term cognitive and psychological consequences, particularly following early-life initiation of use, compounded by high-potency and/or synthetic cannabis, and heavy/frequent use of the drug. Underlying these cognitive and psychiatric consequences are lasting aberrations in the development of synaptic function, often secondary to epigenetic changes. Additional factors such as genetic risk and environmental influences or nondrug toxic insults during development are also profound contributors to these long-term functional alterations following adolescent cannabis use. Preclinical studies indicate that exposure to cannabinoids during specific windows of vulnerability (e.g., adolescence) impacts neurodevelopmental processes and behavior by durably changing dendritic structure and synaptic functions, including those normally mediated by endogenous cannabinoids and neuronal circuits.

Testing for Trenbolone, an Anabolic Steroid, in Biological Fluids and Head Hair in a Post-Mortem Case.

A 60-year-old man was found dead at home by his wife. The man was known to be a regular trainer in a fitness center and was described as a long-term user of anabolic steroids. The autopsy revealed heart failure with a cardiomegaly, a visceral congestion and a pulmonary edema. The local prosecutor ordered toxicological analyses but no anatomic pathology test. Initial analyses by UPLC-q-TOF-MS system indicated the presence in femoral blood of trenbolone, an anabolic steroid. Trenbolone was quantified with a liquid chromatography system coupled with a tandem mass spectrometer in various autopsy specimens, including hair. Concentrations of trenbolone were 3.9, 3.2, 231 and lower than 0.5 ng/mL in femoral blood, cardiac blood, bile and vitreous humor, respectively. Moreover, in head hair the concentration was 9 pg/mg. The presence of trenbolone in hair can be interpreted as repetitive exposures when compared to the limited literature data. Repetitive misuse of trenbolone can explain the advanced heart failure. This paper highlights the importance to test biological specimens for anabolic steroids in case of heart failure.

Unusually high concentrations in a fatal GHB case.

The first case in France involving a fatal overdose resulting from the ingestion of gamma-hydroxybutyrate (GHB) is presented. GHB was tested by gas chromatography-mass spectrometry (GC-MS) after precipitation. Briefly, 20 microL of body fluids (blood, bile, urine, gastric contents, or vitreous humor) was pipetted in a glass tube, followed by 20 microL GHB-d6 and 45 microL acetonitrile. After vortex mixing and centrifuging, the supernatant was collected and evaporated to dryness. The residue was derivatized with BSTFA with 1% TMCS for 20 min at 70 degrees C. After injection on a 30-m HP5 MS capillary column, GHB (m/z 233, 204, and 147) and GHB-d6 (m/z 239) were identified by MS. GHB was also tested in pubic hair after incubation in 0.01 N NaOH, neutralization, acidification, extraction in ethyl acetate and derivatization with MTBSTFA, using GC-MS-MS. GHB was positive in all the tested specimens, with the following concentrations 2937, 33,727, 1800, and 2856 mg/L in femoral blood, urine, bile, and vitreous humor, respectively. This seems to be the highest blood concentration ever observed. Postmortem redistribution appears weak, as the concentration in cardiac blood was 3385 mg/L (cardiac blood/femoral blood ratio of 1.15). Oral route was suggested with GHB at 7.08 g in 100 mL of gastric contents. Pubic hair analysis clearly indicated chronic GHB abuse, with concentrations along the shaft in the range 19.4 to 25.0 ng/mg (in comparison with physiological concentrations < 2 ng/mg). Methylenedioxymethamphetamine was present in femoral blood at 144 ng/mL. These results are consistent with an acute fatal overdose of GHB.

Trafficking through Rab11 endosomes is required for cellularization during Drosophila embryogenesis.

BACKGROUND: Embryonic cleavage leads to the formation of an epithelial layer during development. In Drosophila, the process is specialized and called cellularization. The trafficking pathways that underlie this process and that are responsible for the mobilization of membrane pools, however, remain poorly understood. RESULTS: We provide functional evidence for the role of endocytic trafficking through Rab11 endosomes in remobilizing vesicular membrane pools to ensure lateral membrane growth. Part of the membrane stems from endocytosed apical material. Mutants in the endocytic regulators rab5 and shibire/dynamin inhibit basal-lateral membrane growth, and apical endocytosis is blocked in shibire mutants. In addition, shibire controls vesicular trafficking through Rab11-positive endosomes. In shibire mutants, the transmembrane protein Neurotactin follows the secretory pathway normally but is not properly inserted in the plasma membrane and accumulates instead in Rab11 subapical endosomes. Consistent with a direct role of shibire in vesicular trafficking through Rab11 endosomes, Shibire is enriched in this compartment. Moreover, we show by electron microscopy the large accumulation of intracellular coated pits on subapical endocytic structures in shibire mutants. Finally, we show that Rab11 is essential for membrane growth and invagination during cellularization. CONCLUSION: Together, the data show that endocytic trafficking is required for basal-lateral membrane growth during cellularization. We identify Rab11 endosomes as key trafficking intermediates that control vesicle exocytosis and membrane growth during cellularization. This pathway may be required in other morphogenetic processes characterized by the growth of a membrane domain.

Planar polarity and actin dynamics in the epidermis of Drosophila.

Dorsal closure is a morphogenetic process involving the coordinated convergence of two epithelial sheets to enclose the Drosophila melanogaster embryo. Specialized populations of cells at the edges of each epithelial sheet, the dorsal-most epidermal cells, emit actin-based processes that are essential for the proper enclosure of the embryo. Here we show that actin dynamics at the leading edge is preceded by a planar polarization of the dorsal-most epidermal cells associated with a reorganization of the cytoskeleton. An important consequence of this planar polarization is the formation of actin-nucleating centres at the leading edge, which are important in the dynamics of actin. We show that Wingless (Wg) signalling and Jun amino-terminal kinase (JNK) signalling have overlapping but different roles in these events.