Cocaine profiling method retrospectively developed with nontargeted discovery of markers using liquid chromatography with time-of-flight mass spectrometry data

Illicit drug profiling performed by forensic laboratories assists law enforcement agencies through providing information about chemical and/or physical characteristics of seized specimens. In this article, a model was developed for the comparison of seized cocaine based on retrospective analysis of data generated from ultrahigh performance liquid chromatography with time-of-flight mass spectrometry (UHPLC-TOF-MS) comprehensive drug screening. A nontargeted approach to discover target compounds was employed, which generated 53 potential markers using data from cocaine positive samples. Twelve marker compounds were selected for the development of the final profiling model. The selection included a mixture of commonly used cocaine profiling targets and other cocaine-related compounds. Combinations of pretreatments and comparison metrics were assessed using receiver operating characteristic curves to determine the combination with the best discrimination between linked and unlinked populations. Using data from 382 linked and 34,519 unlinked distances, a classification model was developed using a combination of the standardization and normalization transformations with Canberra distance, resulting in a linked cut-off with a 0.5% false positive rate. The present study demonstrates the applicability of retrospectively developing a cocaine profiling model using data generated from UHPLC-TOF-MS nontargeted drug screening without pre-existing information about cocaine impurities. The developed workflow was not specific to cocaine and thus could potentially be applied to any seized drug in which there are both sufficient data and impurities present.     

Diabetes mellitus and psychological well-being. Change between 1984-1986 and 1995-1997. Results of the Nord-Trøndelag Health Study

Previous research has documented that people with diabetes report lower psychological well-being than do people with no reported disease. In recent years, new treatment regimens for diabetes have been introduced, including improved insulin and tablet treatment, easier blood sugar tests, and transfer of responsibility from doctor to patient. Have these improved methods for controlling diabetes resulted in enhanced psychological well-being for this group of patients? In this paper, we analyze changes in psychological well-being between 1984-1986 and 1995-1997 among diabetic patients. On these two occasions, the entire adult population of one county in Norway was invited to a health screening (the Nord-Tr?ndelag Health Studies, HUNT 1 and HUNT 2). Participants reached 77,224 and 65,599 persons, respectively (90.7% in HUNT 1 and 71.0% in HUNT 2). The participants responded to questionnaires, including questions on several diseases and impairments, as well as self-assessed health and psychological well-being. People with diabetes reported significantly lower well-being than people with no reported diabetes in HUNT 1 as well as in HUNT 2. However, the relationship between diabetes and well-being was significantly weaker in HUNT 2 than in HUNT 1. Self-reported Subjective health, the feeling of being strong and fit, the use of Tranquilizers, and Psychological distress had improved between the two surveys, for people with diabetes compared to people with no reported diabetes. Other outcome variables - Calmness, Cheerfulness, and Life satisfaction - were only weakly related to diabetes, and the relationship did not change significantly from HUNT 1 to HUNT 2.     

CYP3A4 Mediates Oxidative Metabolism of the Synthetic Cannabinoid AKB-48

Synthetic cannabinoid designer drugs have emerged as drugs of abuse during the last decade, and acute intoxication cases are documented in the scientific literature. Synthetic cannabinoids are extensively metabolized, but our knowledge of the involved enzymes is limited. Here, we investigated the metabolism of N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (AKB-48), a compound identified in herbal blends from 2012 and onwards. We screened for metabolite formation using a panel of nine recombinant cytochrome P450 (CYP) enzymes (CYP1A2, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, and 3A4) and compared the formed metabolites to human liver microsomal (HLM) incubations with specific inhibitors against CYP2D6, 2C19, and 3A4, respectively. The data reported here demonstrate CYP3A4 to be the major CYP enzyme responsible for the oxidative metabolism of AKB-48, preferentially performing the oxidation on the adamantyl moiety. Genetic polymorphisms are likely not important with regard to toxicity given the major involvement of CYP3A4. Adverse drug-drug interactions (DDIs) could potentially occur in cases with co-intake of strong CYP3A4 inhibitors, e.g., HIV antivirals and azole antifungal agents.

Electronic supplementary material

The online version of this article (doi:10.1208/s12248-015-9788-7) contains supplementary material, which is available to authorized users.KEY WORDS: adamantyl, cytochrome P450, metabolism, metabolites, synthetic cannabinoids     

Real-time assessment of right and left ventricular volumes and function in children using high spatiotemporal resolution spiral bSSFP with compressed sensing

Background

Real-time cardiovascular magnetic resonance (CMR) assessment of ventricular volumes and function enables data acquisition during free-breathing. The requirement for high spatiotemporal resolution in children necessitates the use of highly accelerated imaging techniques.

Methods

A novel real-time balanced steady state free precession (bSSFP) spiral sequence reconstructed using Compressed Sensing (CS) was prospectively validated against the breath-hold clinical standard for assessment of ventricular volumes in 60 children with congenital heart disease. Qualitative image scoring, quantitative image quality, as well as evaluation of biventricular volumes was performed. Standard BH and real-time measures were compared using the paired t-test and agreement for volumetric measures were evaluated using Bland Altman analysis.

Results

Acquisition time for the entire short axis stack (~?13 slices) using the spiral real-time technique was ~?20 s, compared to ~?348 s for the standard breath hold technique. Qualitative scores reflected more residual aliasing artefact (p?<?0.001) and lower edge definition (p?<?0.001) in spiral real-time images than standard breath hold images, with lower quantitative edge sharpness and estimates of image contrast (p?<?0.001).There was a small but statistically significant (p?<?0.05) overestimation of left ventricular (LV) end-systolic volume (1.0?±?3.5 mL), and underestimation of LV end-diastolic volume (??1.7?±?4.6 mL), LV stroke volume (??2.6?±?4.8 mL) and LV ejection fraction (??1.5?±?3.0%) using the real-time technique. We also observed a small underestimation of right ventricular stroke volume (??1.8?±?4.9 mL) and ejection fraction (??1.4?±?3.7%) using the real-time imaging technique. No difference in inter-observer or intra-observer variability were observed between the BH and real-time sequences.

Conclusions

Real-time bSSFP imaging using spiral trajectories combined with a compressed sensing reconstruction showed good agreement for quantification of biventricular metrics in children with heart disease, despite slightly lower image quality. This technique holds the potential for free breathing data acquisition, with significantly shorter scan times in children.

     

Closed-loop regulation of arterial pressure after acute brain death

The purpose of this concept study was to investigate the possibility of automatic mean arterial pressure (MAP) regulation in a porcine heart-beating brain death (BD) model. Hemodynamic stability of BD donors is necessary for maintaining acceptable quality of donated organs for transplantation. Manual stabilization is challenging, due to the lack of vasomotor function in BD donors. Closed-loop stabilization therefore has the potential of increasing availability of acceptable donor organs, and serves to indicate feasibility within less demanding patient groups. A dynamic model of nitroglycerine pharmacology, suitable for controller synthesis, was identified from an experiment involving an anesthetized pig, using a gradient-based output error method. The model was used to synthesize a robust PID controller for hypertension prevention, evaluated in a second experiment, on a second, brain dead, pig. Hypotension was simultaneously prevented using closed-loop controlled infusion of noradrenaline, by means of a previously published controller. A linear model of low order, with variable (uncertain) gain, was sufficient to describe the dynamics to be controlled. The robustly tuned PID controller utilized in the second experiment kept the MAP within a user-defined range. The system was able to prevent hypertension, exceeding a reference of 100 mmHg by more than 10%, during 98% of a 12 h experiment. This early work demonstrates feasibility of the investigated modelling and control synthesis approach, for the purpose of maintaining normotension in a porcine BD model. There remains a need to characterize individual variability, in order to ensure robust performance over the expected population.