Background: The role of leukotriene (LT) B 4 , a potent inflammatory mediator, in atopic asthmatic and atopic nonasthmatic children is largely unknown. The lack of a gold standard technique for measuring LTB 4 in exhaled breath condensate (EBC) has hampered its quantitative assessment in this biological fluid. We sought to measure LTB 4 in EBC in atopic asthmatic children and atopic nonasthmatic children. Exhaled nitric oxide (NO) was measured as an independent marker of airway inflammation.
The objective of this study is the measurement of leukotriene B7 (LTB4), a potent inflammatory mediator, in exhaled breath condensate by using liquid chromatography/mass spectrometry (LC/MS and LC/MS/MS). Condensation of exhaled breath is a non-invasive method to collect airway secretions. Deuterated (d4)-LTB4 was used as internal standard. The MS and MS/MS behavior of LTB4 and LTB4-d4 was studied by electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) in both positive and negative ion polarity mode. Preliminary results show that monitoring negative ions in ESI mode has the best sensitivity for both LTB4 and LTB4-d4. Therefore, negative ESI was chosen, and the [M-H]- ions at m/z 335 and 339 were selected for quantification. The lower limit of quantification for LTB4, expressed as the lowest point of the calibration curve, was 100 pg/mL. Using this technique, we measured LTB4 in exhaled breath condensate in two healthy subjects, four asthmatic patients on anti-inflammatory treatment, and four asthmatic patients who were not on anti-inflammatory drugs. Exhaled LTB4 concentrations were detected only in asthmatic patients who were not on anti-inflammatory therapy. This method is potentially useful for non-invasive assessment of airway inflammation, but the sensitivity of the technique needs to be improved.
Genetic markers can be used in seeds and in plants to distinguish drug-type from fiber-type Cannabis Sativa L. varieties even at early stages, including pre-germination when cannabinoids are not accumulated yet. With this aim, this paper reports sequencing results for tetrahydrocannabinolic acid synthase (THCAS) and cannabidiolic acid synthase (CBDAS) genes from 21 C. sativa L. varieties. Taking into account that THCAS- and CBDAS-derived enzymes compete for the same substrate, the novelty of this work relies in the identification of markers based on both THCAS and CBDAS rather than THCAS alone. Notably, in our panel, we achieved an adequate degree of discrimination (AUC 100%) between drug-type and fiber-type cannabis samples. Our sequencing approach allowed identifying multiple genetic markers (single-nucleotide polymorphisms—SNPs—and a deletion/insertion) that effectively discriminate between the two subgroups of cannabis, namely fiber type vs. drug type. We identified four functional SNPs that are likely to induce decreased THCAS activity in the fiber-type cannabis plants. We also report the finding on a deletion in the CBDAS gene sequence that produces a truncated protein, possibly resulting in loss of function of the enzyme in the drug-type varieties. Chemical analyses for the actual concentration of cannabinoids confirmed the identification of drug-type rather than fiber-type genotypes. Genetic markers permit an early identification process for forensic applications while simplifying the procedures related to detection of therapeutic or industrial hemp.
Several studies have highlighted that nutritional supplements may contain undeclared substances that are banned by the International Olympic Committee (IOC)/World Anti-Doping Agency (WADA). This paper describes a qualitative liquid chromatography coupled with tandem mass spectrometry detection (LC-MS/MS) method to detect anabolic androgenic steroids (4-androsten-3,17-dion, 4-oestren-3,17-dion, 5alpha-androsten-17beta-ol-3-one, boldenone, nandrolone, nandrolone decanoate, testosterone, and testosterone decanoate) and ephedrine in food supplements. The products are dissolved in methanol and analysed by gas chromatography-mass spectrometry (GC-MS). The methanolic solution was added to testosterone-d(3), evaporated to dryness, mixed with NaOH and extracted with n-pentane:diethylether (9:1). LC-MS/MS analyses were performed in selected reaction monitoring (SRM) on an ion-trap equipped with an atmospheric pressure chemical ionization (APCI) probe operating in positive-ion mode. The method was applied to 64 nutritional supplements. A total of 12.5% of the nutritional supplements analysed contained banned substances not declared on the label (anabolic steroids and ephedrine). Detection limits were in the range 1-25 ng g(-1).
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