The coronavirus disease 2019 (COVID-19) has developed into a serious pandemic with millions of cases diagnosed worldwide. To fight COVID-19 pandemic, over 100 countries instituted either a full or partial lockdown, affecting billions of people. In Tyrol, first lockdown measures were taken on 10 March 2020. On 16 March 2020, a curfew went into force which ended on 1 May 2020. On 19 March 2020, Tyrol as a whole was placed in quarantine which ended on 7 April 2020. The governmental actions helped reducing the spread of COVID-19 at the cost of significant effects on social life and behaviour. Accordingly, to provide a comprehensive picture of the population health status not only input from medical and biological sciences is required, but also from other sciences able to provide lifestyle information such as drug use. Herein, wastewater-based epidemiology was used for studying temporal trends of licit and illicit drug consumption during lockdown and quarantine in the area of the Tyrolean capital Innsbruck (174,000 inhabitants). On 35 days between 12 March 2020 and 15 April 2020, loads of 23 markers were monitored in wastewater. Loads determined on 292 days between March 2016 and January 2020 served as reference. During lockdown, changes in the consumption patterns of recreational drugs (i.e. cocaine, amphetamine, 3,4-methylenedioxymethamphetamine, methamphetamine, and alcohol) and pharmaceuticals for short-term application (i.e. acetaminophen, codeine, and trimethoprim) were detected. For illicit drugs and alcohol, it is very likely that observed changes were linked to the shutdown of the hospitality industry and event cancelation which led to a reduced demand of these compounds particularly on weekends. For the pharmaceuticals, further work will be necessary to clarify if the observed declines are indicators of improved population health or of some kind of restraining effect that reduced the number of consultations of medical doctors and pharmacies.
Oral fluid is recognized as an important specimen for drug testing. Common applications are monitoring in substance abuse treatment programs, therapeutic drug monitoring, pain management, workplace drug testing, clinical toxicology, and driving under the influence of drugs (DRUID). In this study, we demonstrate that non-targeted LC-MS/MS with subsequent compound identification by tandem mass spectral library search is a valuable tool for comprehensive detection and confirmation of drugs in oral fluid samples. The workflow developed involves solid-phase extraction and chromatographic separation on reversed phase materials. Mass spectrometric detection is accomplished on a quadrupole–quadrupole-time-of-flight instrument operated with data-dependent acquisition control. The workflow was optimized for 500 μl of neat oral fluid collected with the Greiner Bio-One saliva collection system. The fitness of the developed method was tested and proven by analyzing blank and spiked samples as well as 59 authentic patient samples. We could demonstrate that compounds with logP values in the range 0.5–5.5 are efficiently detected at low nanograms per milliliter concentrations. The true positive and true negative rates of automated library search were equal or close to 100%. The beauty of the non-targeted LC-MS/MS approach is the ability to detect compounds hardly included in routinely applied targeted assays, and this was demonstrated by detecting the synthetic opioid U-47700 in two patient samples.
Mass spectral library annotation of liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) data is a reliable approach for fast identification of organic contaminants and toxicants in complex environmental and biological matrices. While determining the exposure of humans or mammals, it is indispensable to include phase I and phase II metabolites (conjugates) along with the parent compounds, but often, tandem mass spectra for these are unavailable. In this study, we present and evaluate a strategy for annotating glucuronide conjugates in LC-HRMS/MS scans by applying a neutral loss search for detection, then truncating the spectra which we refer to as in silico deconjugation, and finally searching these against mass spectral libraries of the aglycones. The workflow was tested on a dataset of in vitro-generated glucuronides of reference standard mixtures and a dataset of 51 authentic urine samples collected from patients with known medication status, acquired on different instrumentations. A total number of 75 different glucuronidated molecular structures were identified by in silico deconjugation and spectral library annotation. We also identified specific molecular structures (sulfonamides, ether bonds, di-glucuronides), which resulted in slightly different fragmentation patterns between the glucuronide and the unconjugated compound. This led to a decreased spectral matching score and in some cases to a false-negative identification. Still, by applying this method, we revealed a reliable annotation of most common glucuronides, leading to a new strategy reducing the need for deconjugation steps or for recording many reference glucuronide spectra for screening approaches.
Although the exposure assessment of chemicals of emerging concern (CECs) has taken a decisive step forward through advances in (bio)informatics, statistics, and the development of highly sophisticated analytical instruments, the lack of standardisation and harmonisation of analytical workflows and method performance assessment for suspect and non-target screening hampers the interpretation of results, their comparability and thus, its transmission to policymakers. To date, unlike in other research fields such as forensics or food analysis, there is a lack of guidelines for non-target analysis in human risk assessment and quality assurance and quality control (QA/QC) protocols. Moreover, the majority of efforts have been focused on the development and implementation of QA/QC actions for data acquisition, data analysis and mining, largely neglecting the sample preparation necessary for determination of CECs by suspect and non-target screening methods. In this article, we propose a set of QA/QC measures that covers sampling, sample preparation and data acquisition, as an aspect of work conducted within the European Biomonitoring for Europe initiative (HBM4EU). These measures include the use of standardised terminology and the implementation of dedicated QA/QC actions in each stage of the analytical process. Moreover, a framework for the analytical performance assessment has been developed for the first time for the identification of CECs in human samples by suspect and non-target approaches. Adoption of the actions proposed here for the identification of CECs in human matrices can significantly improve the comparability of reported results and contribute to the (challenging) Exposome research field.
Liposomal cytarabine is a slow-release formulation for intrathecal application in patients with neoplastic meningitis. Although standard dosing intervals range from 2 to 4 weeks, it is unclear whether sustained cytotoxic cerebrospinal fluid (CSF) concentrations can be achieved beyond 14 days from drug injection. The objective of this study was to assess CSF and plasma concentrations of liposomal cytarabine more than 2 weeks after lumbar drug administration and to correlate those findings with clinical outcome.66 matched CSF and plasma drug concentrations were analyzed by a validated liquid chromatography-tandem mass spectrometry method starting at day 13 from lumbar drug injection in 19 patients with neoplastic meningitis treated with liposomal cytarabine. CSF drug concentrations were correlated with clinical outcome.Overall response rate was 63.2% (12/19). 100% (9/9) of patients with positive CSF cytology at diagnosis achieved cytological complete remission, and none of the patients (0/19) experienced on-drug disease progression. In responding patients with controlled systemic disease, CNS-specific progression-free survival was 14 months (n = 4; range 5-25 months). The median CSF concentration of free cytarabine was 156 ng/ml (range 5-4581 ng/ml) and 146 ng/ml (range 5-353 ng/ml) in samples withdrawn at days 13-16 and at days 25-29 after intrathecal drug injection, respectively. Free cytarabine concentrations > 100 ng/ml were detected in 58.8% (20/34) and 53.3% (7/13) of the CSF samples obtained at days 13-16 and days 25-29, respectively. CSF drug concentrations did not differ significantly between responding and nonresponding patients.Liposomal cytarabine permits prolonged CSF drug exposure, with cytotoxic cytarabine concentrations that are detectable for 4 weeks in the majority of patients. The preserved clinical activity seen in patients with inferior CSF drug concentrations (< 100 ng/ml) suggests that maintaining lower cytarabine concentrations for a longer period of time may be similarly effective as using short peak concentrations.
Hintergrund Die Wichtigkeit vom JAK/STAT Signalweg in Bezug auf Entzündungskrankheiten führte zur Entwicklung niedermolekularer JAK Inhibitoren. Tofacitinib wurde bereits 2018 für die Behandlung von Colitis Ulcerosa zugelassen. Dennoch gibt es weiterhin offene Fragen zum Mechanismus von Tofacitinib insbesondere in Bezug auf eine mögliche zellspezifische Selektivität und der Pharmakokinetik in Abhängigkeit vom zellulären Aktivierungsstatus.
Proton-transfer reaction mass spectrometry (PTR-MS) is a versatile tool for the mass spectrometric analysis of organic molecules in gaseous samples. Due to its operation principle, PTR-MS is a soft ionization technique generating spectral data typically rich in protonated molecule information. Most of the currently reported PTR-MS applications are designed to determine volatile compounds. Herein, we present a redesigned instrumental setup termed “high-temperature (HT)-PTR-MS” with improved capabilities for the analysis of low-volatile compounds. The developed HT-PTR-MS prototype was successfully hyphenated with gas chromatography (GC) to enable qualitative and quantitative analysis of licit and illicit drugs in human blood/plasma samples. Different kinds of spiked and authentic samples were used to evaluate the performance of the GC-HT-PTR-MS in forensic drug testing. Benchmarking against GC-MS with electron ionization demonstrated the improved detection capabilities of GC-HT-PTR-MS in screening applications. On average, one order of magnitude lower limits of detection/identification were reached. Clearly, GC-HT-PTR-MS has the vast potential to complement or even replace established mass spectrometric techniques in forensic drug analysis.
